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Sample records for retrieved cross-correlation function

  1. Unified Green's Function Retrieval by Cross Correlation

    SciTech Connect

    Wapenaar, Kees; Slob, Evert; Snieder, Roel

    2006-12-08

    It has been shown by many authors that the cross correlation of two recordings of a diffuse wave field at different receivers yields the Green's function between these receivers. Recently the theory has been extended for situations where time-reversal invariance does not hold (e.g., in attenuating media) and where source-receiver reciprocity breaks down (in moving fluids). Here we present a unified theory for Green's function retrieval that captures all these situations and, because of the unified form, readily extends to more complex situations, such as electrokinetic Green's function retrieval in poroelastic or piezoelectric media. The unified theory has a wide range of applications in ''remote sensing without a source.''.

  2. Unified Green's function retrieval by cross-correlation; connection with energy principles.

    PubMed

    Snieder, Roel; Wapenaar, Kees; Wegler, Ulrich

    2007-03-01

    It has been shown theoretically and observationally that the Green's function for acoustic and elastic waves can be retrieved by cross-correlating fluctuations recorded at two locations. We extend the concept of the extraction of the Green's function to a wide class of scalar linear systems. For systems that are not invariant under time reversal, the fluctuations must be excited by volume sources in order to satisfy the energy balance (equipartitioning) that is needed to extract the Green's function. The general theory for retrieving the Green's function is illustrated with examples that include the diffusion equation, Schrödinger's equation, a vibrating string, the acoustic wave equation, a vibrating beam, and the advection equation. Examples are also shown of situations where the Green's function cannot be extracted from ambient fluctuations. The general theory opens up new applications for the extraction of the Green's function from field correlations that include flow in porous media, quantum mechanics, and the extraction of the response of mechanical structures such as bridges.

  3. Information retrieval and cross-correlation function analysis of random noise radar signal through dispersive media

    NASA Astrophysics Data System (ADS)

    Alejos, Ana Vazques; Dawood, Muhammad

    2012-06-01

    In this contribution we examine the propagation of an ultrawideband (UWB) random noise signal through dispersive media such as soil, vegetation, and water, using Fourier-based analysis. For such media, the propagated signal undergoes medium-specific impairments which degrade the received signal in a different way than the non-dispersive propagation media. Theoretically, larger penetration depths into a dispersive medium can be achieved by identifying and detecting the precursors, thereby offering significantly better signal-to-noise ratio and enhanced imaging. For a random noise signal, well defined precursors in term of peak-amplitude don't occur. The phenomenon must therefore be studied in terms of energy evolution. Additionally, the distortion undergone by the UWB random noise signal through a dispersive medium can introduce frequency-dependent uncertainty or noise in the received signal. This leads to larger degradation of the cross-correlation function (CCF), mainly in terms of sidelobe levels and main peak deformation, and consequently making the information retrieval difficult. We would further analyze one method to restore the shape and carrier frequency of the input UWB random noise signal, thereby, improving the CCF estimation.

  4. Near-field effects in Green's function retrieval from cross-correlation of elastic fields: experimental study with application to elastography.

    PubMed

    Benech, N; Brum, J; Catheline, S; Gallot, T; Negreira, C

    2013-05-01

    In a lossless system, the causal and acausal Green's function for elastic waves can be retrieved by cross-correlating the elastic field at two positions. This field, composed of converging and diverging waves, is interpreted in the frame of a time-reversal process. In this work, the near-field effects on the spatio-temporal focusing of elastic waves are analyzed through the elastodynamic Green's function. Contrary to the scalar field case, the spatial focusing is not symmetric preserving the directivity pattern of a simple source. One important feature of the spatial asymmetry is its dependency on the Poisson ratio of the solid. Additionally, it is shown that the retrieval of the bulk wave speed values is affected by diffraction. The correction factor depends on the relative direction between the source and the observed field. Experimental verification of the analysis is carried out on the volume of a soft-solid. A low-frequency diffuse-like field is generated by random impacts at the sample's free surface. The displacement field is imaged using ultrasound by a standard speckle tracking technique. One important application of this work is in the estimation of the shear elastic modulus in soft biological tissues, whose quantification can be useful in non-invasive diagnosis of various diseases.

  5. CCFpams: Atmospheric stellar parameters from cross-correlation functions

    NASA Astrophysics Data System (ADS)

    Malavolta, Luca; Lovis, Christophe; Pepe, Francesco; Sneden, Christopher; Udry, Stephane

    2017-07-01

    CCFpams allows the measurement of stellar temperature, metallicity and gravity within a few seconds and in a completely automated fashion. Rather than performing comparisons with spectral libraries, the technique is based on the determination of several cross-correlation functions (CCFs) obtained by including spectral features with different sensitivity to the photospheric parameters. Literature stellar parameters of high signal-to-noise (SNR) and high-resolution HARPS spectra of FGK Main Sequence stars are used to calibrate the stellar parameters as a function of CCF areas.

  6. Analog computation of auto and cross-correlation functions

    NASA Technical Reports Server (NTRS)

    1974-01-01

    For analysis of the data obtained from the cross beam systems it was deemed desirable to compute the auto- and cross-correlation functions by both digital and analog methods to provide a cross-check of the analysis methods and an indication as to which of the two methods would be most suitable for routine use in the analysis of such data. It is the purpose of this appendix to provide a concise description of the equipment and procedures used for the electronic analog analysis of the cross beam data. A block diagram showing the signal processing and computation set-up used for most of the analog data analysis is provided. The data obtained at the field test sites were recorded on magnetic tape using wide-band FM recording techniques. The data as recorded were band-pass filtered by electronic signal processing in the data acquisition systems.

  7. Noise cross correlation functions in a noisy region

    NASA Astrophysics Data System (ADS)

    Gaudot, I.; Beucler, E.; Mocquet, A.; Schimmel, M.; Le Feuvre, M.; Leparoux, D.; Côte, P.

    2013-12-01

    The geology of the western France can be roughly split into two main domains: the Armorican massif that contains imprints of the old Cadomian and Variscan orogens; and the Bay of Biscay which present signatures of more recent tectonic events closely related to the opening of North Atlantic ocean. Due to the lack of seismic stations deployment, it exists very few pictures of the deep structures below the Armorican Massif and the Bay of Biscay. Recently, a broadband array of seismometers has been deployed over the south and west of France, providing a good opportunity to get reliable images at depth. Since the region is surrounded by the seas, the seismic ambient noise tomography technique has been proposed to reveal the crustal and uppermost mantle features beneath this area. The first step consists in the computation of noise correlation functions (NCFs) between each station pairs. The ability to obtain empirical Green's functions from NCFs relies on the efficiency of the randomization. Classic ambient noise tomography studies use long-time series (typically several months) to help the randomization including all the scattering effects due to Earth's heterogeneities. However, additionnal signal processing steps such as temporal and/or spectral whitening are most often required for the signals to be representative of a random wavefield. These techniques rely on nonlinear operations which corrupt the integrity of the original record. In the literature, alternatives have been proposed to avoid, at least partially, such non linear operations. One of them is the instantaneous phase cross correlation (PCC). This correlation technique is intrinsically little sensitive to large amplitude transient signals. Using a set of data from a temporary broad band array, we explore the features of the PCC as compared to the time domain geometrically normalized cross correlation (CCGN). In the 0.02Hz-1Hz frequency band, different time series are extracted to investigate the effects of

  8. Extraction of noise cross-correlation function with topography

    NASA Astrophysics Data System (ADS)

    Ping, P.; Chu, R.; Zhang, Y.

    2016-12-01

    Due to the increasing popularity of analyzing empirical Green's functions obtained from ambient noise, more regional tomographical studies based on short-period surface waves are published. The propagation of surface waves from noise cross-correlation function (NCF) could potentially be biased in local regions where topography is not small compared with the wavelength and penetration of the waves. We investigate these effects of topography on the extraction of NCF by synthetic data in a typical 3D topography model. Sufficient surface wave dispersion bias analysis on this type of topography is also presented. Different thicknesses of the layers along the topography may generate different scale dispersion perturbations. These phenomena suggest a cautious preprocessing for high SNR NCF extraction in the topographic region. An apparent statistical regularity drawn from the numerical experiments can favor a possible guidance for accurate NCF extractions. Through the numerical validations, we can conclude that: 1) when the stations are located on the topographic regions, the SNR of NCF could be enhanced with the vertical station component rotation perpendicular to the inclined surface; 2) the dispersion curves move to low frequencies, which lead to false thickness reductions of the near surface layers; 3) An error plane can be built for this perturbation on the true thickness of the layers and the topography scale to eliminate this misleading in practical dispersion analysis of NCFs.

  9. Atmospheric stellar parameters from cross-correlation functions

    NASA Astrophysics Data System (ADS)

    Malavolta, L.; Lovis, C.; Pepe, F.; Sneden, C.; Udry, S.

    2017-08-01

    The increasing number of spectra gathered by spectroscopic sky surveys and transiting exoplanet follow-up has pushed the community to develop automated tools for atmospheric stellar parameters determination. Here we present a novel approach that allows the measurement of temperature (Teff), metallicity ([Fe/H]) and gravity (log g) within a few seconds and in a completely automated fashion. Rather than performing comparisons with spectral libraries, our technique is based on the determination of several cross-correlation functions (CCFs) obtained by including spectral features with different sensitivity to the photospheric parameters. We use literature stellar parameters of high signal-to-noise (SNR), high-resolution HARPS spectra of FGK main-sequence stars to calibrate Teff, [Fe/H] and log g as a function of CCF parameters. Our technique is validated using low-SNR spectra obtained with the same instrument. For FGK stars we achieve a precision of σ _{{T_eff}} = 50 K, σlog g = 0.09 dex and σ _{{{[Fe/H]}}} =0.035 dex at SNR = 50, while the precision for observation with SNR ≳ 100 and the overall accuracy are constrained by the literature values used to calibrate the CCFs. Our approach can easily be extended to other instruments with similar spectral range and resolution or to other spectral range and stars other than FGK dwarfs if a large sample of reference stars is available for the calibration. Additionally, we provide the mathematical formulation to convert synthetic equivalent widths to CCF parameters as an alternative to direct calibration. We have made our tool publicly available.

  10. Experimental Study of the Convergence of Two-Point Cross-Correlation Toward the Green's Function

    NASA Astrophysics Data System (ADS)

    Gouedard, P.; Roux, P.; Campillo, M.; Verdel, A.; Campman, X.

    2007-12-01

    It has been shown theoretically by several authors that cross-correlation of the seismic motion recorded at two points could yield the Green's Function (GF) between these points. Convergence of cross-correlations toward the GF depends on sources positions and/or the nature of the wavefield. Direct waves from an even distribution of sources can be used to retrieve the GF. On the other hand, in an inhomogeneous medium, recording the diffuse field (coda) is theoretically sufficient to retrieve the GF whatever the sources distribution is. Since none of these two conditions (even distribution of sources or a perfectly diffuse field) is satisfied in practice, the question of convergence toward the GF has to be investigated with real data. A 3D exploration survey with sources and receivers on a dense grid offers such an opportunity. We used a high- resolution survey recorded by Petroleum Development Oman in North Oman. The data have been obtained in a 1x1~km area covered with 1600 geophones located on a 25x25~m-cell grid. Records are 4-seconds long. A unique feature of this survey is that vibrators (working in the [8-120~Hz] frequency band), were located on a similar grid shifted with respect to the receiver grid by half a cell (12.5~m) in both directions. This allows us to compare estimated GF's with measured direct waves (GF's) between the geophones. The shallow subsurface is highly heterogeneous and records include seismic coda. From this dataset, we selected two receiver locations (Ra and Rb) distant from d=158~m. We used both different sets of source locations and time windows to compute the cross-correlation between these two receivers. Then we compared the derivatives of correlation functions with the actual GF measured in Rb (resp.~Ra) for a source close to Ra (resp.~Rb). By doing so, we show the actual influence of source locations and scattering (governed by the records' selected time window) on the Signal-to-Noise Ratio (SNR) of the reconstructed GF. When using

  11. Cross-correlation function of acoustic fields generated by random high-frequency sources.

    PubMed

    Godin, Oleg A

    2010-08-01

    Long-range correlations of noise fields in arbitrary inhomogeneous, moving or motionless fluids are studied in the ray approximation. Using the stationary phase method, two-point cross-correlation function of noise is shown to approximate the sum of the deterministic Green's functions describing sound propagation in opposite directions between the two points. Explicit relations between amplitudes of respective ray arrivals in the noise cross-correlation function and the Green's functions are obtained and verified against specific problems allowing an exact solution. Earlier results are extended by simultaneously accounting for sound absorption, arbitrary distribution of noise sources in a volume and on surfaces, and fluid inhomogeneity and motion. The information content of the noise cross-correlation function is discussed from the viewpoint of passive acoustic characterization of inhomogeneous flows.

  12. Optimisation of sea surface current retrieval using a maximum cross correlation technique on modelled sea surface temperature

    NASA Astrophysics Data System (ADS)

    Heuzé, Céline; Eriksson, Leif; Carvajal, Gisela

    2017-04-01

    Using sea surface temperature from satellite images to retrieve sea surface currents is not a new idea, but so far its operational near-real time implementation has not been possible. Validation studies are too region-specific or uncertain, due to the errors induced by the images themselves. Moreover, the sensitivity of the most common retrieval method, the maximum cross correlation, to the three parameters that have to be set is unknown. Using model outputs instead of satellite images, biases induced by this method are assessed here, for four different seas of Western Europe, and the best of nine settings and eight temporal resolutions are determined. For all regions, tracking a small 5 km pattern from the first image over a large 30 km region around its original location on a second image, separated from the first image by 6 to 9 hours returned the most accurate results. Moreover, for all regions, the problem is not inaccurate results but missing results, where the velocity is too low to be picked by the retrieval. The results are consistent both with limitations caused by ocean surface current dynamics and with the available satellite technology, indicating that automated sea surface current retrieval from sea surface temperature images is feasible now, for search and rescue operations, pollution confinement or even for more energy efficient and comfortable ship navigation.

  13. On the growth-speed of the ambient noise cross-correlation function and its application

    NASA Astrophysics Data System (ADS)

    Chen, Ying-Nien; Gung, Yuancheng; Chiao, Ling-Yun

    2013-04-01

    Retrieving the Empirical Green's function (EGF) between two receivers by cross-correlating continuous records is now a well-recognized technique and the derived EGFs have been applied to various fields of seismology. In the common operation of noise cross-correlation, it is known that the signal-to-noise ratio (SNR) of cross-correlation functions (CCF) is generally increasing with the total correlation time. However, little attention has been given to a more quantitative description on how the noise-derived CCFs are developing with time. In this study, we analyze the CCF growth-speed quantitatively, and discuss its potential applications. In theory, the noise-derived CCF is approximately composed of two parts, the time-independent term, which is related to the Green's function, and the time-dependent term, which is the product of unrelated noise sources, and its contribution in the CCF is decreasing with the total correlation time. Defining the final CCF, the one derived from all the available data, as the reference CCF, we may quantify the strength of unrelated noise sources using the rms of the waveform residual between a target CCF and the reference CCF. Since the rms is dropping with the growing correlation time of the target CCF, we may relate the rms to the CCF growth-speed when it is scaled by a properly defined time-dependent term. We evaluate the growth-speed for realistic CCF data set derived from the vertical component continuous seismic data recorded at 63 short period stations and 89 broadband stations in Taiwan. To remove the effects of temporal variations of the noises strength, the growing target CCFs are taken from a randomly daily CCF stack. In Taiwan, we have noted that the noise excitations in the frequency band of short period secondary microseism (3-7 seconds) is highly correlated with the the water depth of the surrounding ocean, and its signature is clearly shown in the resulting CCFs. Interestingly, such correlations do not exist in the CCF

  14. On the growth-speed of the ambient noise cross-correlation function and its application

    NASA Astrophysics Data System (ADS)

    Chen, Y.; Gung, Y.; Chiao, L.

    2013-12-01

    Retrieving the Empirical Green's function (EGF) between two receivers by cross-correlating continuous records is now a well-recognized technique and the derived EGFs have been applied to various fields of seismology. In the common operation of noise cross-correlation, it is known that the signal-to-noise ratio (SNR) of cross-correlation functions (CCF) is generally increasing with the total correlation time. However, little attention has been given to a more quantitative description on how the noise-derived CCFs are developing with time. In this study, we analyze the CCF growth-speed quantitatively, and discuss its potential applications. In theory, the noise-derived CCF can be approximately composed of two parts, the time-independent term, which is related to the Green's function, and the time-dependent term, which is the product of unrelated noise sources, and its contribution in the CCF is decreasing with the total correlation time. Defining the final CCF, the one derived from all the available data, as the reference CCF, we may quantify the strength of unrelated noise sources using the rms of the waveform residual between a target CCF and the reference one. Since the rms is dropping with the growing correlation time of the target CCF, we may relate the rms to the CCF growth-speed when it is scaled by a properly defined time-dependent term. We evaluate the growth-speed for realistic CCF data set derived from the vertical component continuous seismic data recorded at 45 and 17 broadband stations in Taiwan and Korea, respectively. To remove the effects of temporal variations of the noises strength, the growing target CCFs are taken from a randomly daily CCF stack. Assuming the CCF with infinite correlation time is "noise-free", we may evaluate the "noises" strength in the CCFs at any given correlation time with the growth-speed. Instead of using an empirically defined SNR, the estimated "noise" strength provides a quantitative measure for the EGF quality. Such

  15. Analysis of Green functions obtained by cross-correlations for MASE stations

    NASA Astrophysics Data System (ADS)

    Padilla, G. V. Vera

    2012-04-01

    We used continuous records of broadband seismic stations of the MASE experiment to obtain observed Green's functions using the method of ambient noise cross-correlations. The experiment consisted of 100 stations distributed along a perpendicular line to the Mesoamerican trench across the Valley of Mexico. The stations recorded continuously at 100 sps for more than two years. The geometry of the array provide a good opportunity to study the attenuation effects along the coast-perpendicular structure. The method we used to compute Green functions involves a strong data pre-processing (temporal normalization and spectral whitening). However, our results show that the amplitude of the cross-correlations still contains information about the surface waves attenuation and probably local amplification effects. Records from two regional earthquakes located close to Acapulco were used for comparison.

  16. Two-dimensional turbulence cross-correlation functions in the edge of NSTX

    DOE PAGES

    Zweben, S. J.; Stotler, D. P.; Scotti, F.; ...

    2017-09-26

    The 2D radial vs. poloidal cross-correlation functions of edge plasma turbulence were measured near the outer midplane using a gas puff imaging (GPI) diagnostic on NSTX. These correlation functions were evaluated at radii r = 0 cm, ±3 cm, and ±6 cm from the separatrix and poloidal locations p = 0 cm and ±7.5 cm from the GPI poloidal center line for 20 different shots. The ellipticity ε and tilt angle φ of the positive cross-correlation regions and the minimum negative cross-correlation “cmin” and total negative over positive values “neg/pos” were evaluated for each of these cases. The average resultsmore » over this dataset were ε = 2.2 ± 0.9, φ = 87° ± 34° (i.e., poloidally oriented), cmin =-0.30 ± 0.15, and neg/pos = 0.25 ± 0.24. Thus, there was a significant variation in these correlation results within this database, with dependences on the location within the image, the magnetic geometry, and the plasma parameters. In conclusion, possible causes for this variation are discussed, including the misalignment of the GPI view with the local B field line, the magnetic shear of field lines at the edge, the poloidal flow shear of the turbulence, blob-hole correlations, and the neutral density 'shadowing' effect in GPI.« less

  17. Non-linear Inversion of Noise Cross-correlations Using Probability Density Functions of Surface Waves Dispersion

    NASA Astrophysics Data System (ADS)

    Gaudot, I.; Beucler, E.; Mocquet, A.; Drilleau, M.; Le Feuvre, M.

    2015-12-01

    Cross-correlations of ambient seismic noise are widely used to retrieve the information of the medium between pairs of stations. For periods between 1 and 50 s, the diffuse wavefield is dominated by microseismic energy which travels mostly as surface waves. Therefore, such waves are mainly reconstructed in the cross-correlations, and information about the structure are obtained using dispersion analysis, i.e computing phase or group velocities. Classical group velocity determination relies on tracking the maximum energy in the dispersion diagrams in order to get a unique dispersion curve. This procedure may often present problems due to the presence of several maxima. Moreover, the estimation of associated measurement errors usually depends on ad hoc user's criteria. We handle the non-unicity of the problem by inverting the whole dispersion diagram using a non-linear inversion scheme. For each frequency, the seismic energy is mapped into a time-dependent probability density function. The resulting map is inverted for the S-wave velocity structure using a Markov-chain Monte Carlo algorithm. Each time a new model is randomly sampled, the misfit value is computed according to the position of the corresponding group velocity curve in the probability density functions map. This method is applied for the analysis of vertical component noise cross-correlations computed from seismic data recorded in western Europe by the temporary PYROPE and IBERARRAY networks. The inversion of the fundamental mode Rayleigh wave dispersion diagrams between 5 and 50 s period gives a set of 1D S-wave velocity models, which are regionalized to infer a 3D S-wave velocity model of western France.

  18. Tomographic inversion of measured cross-correlation functions of ocean noise in shallow water using ray theory

    NASA Astrophysics Data System (ADS)

    Goncharov, V. V.; Shurup, A. S.; Godin, O. A.; Zabotin, N. A.; Vedenev, A. I.; Sergeev, S. N.; Brown, M. G.; Shatravin, A. V.

    2016-07-01

    Based on experimental data obtained in 2012 in the Florida Strait, we study the feasibility of employing ray tomography to retrieve sound speed and flow velocity profiles from measured noise cross-correlation functions. We describe the results of numerical experiments that characterize the inversion errors resulting from peculiarities of the ray structure in shallow water, difficulties in unambiguous identification of ray arrivals, and a decrease in accuracy of ray theory at low frequencies. We show that under conditions of low-mode sound propagation, the use of the classical ray tomography scheme can yield only a rough estimate of the sound speed profile, but it allows approximate reconstruction of the current velocity profile. Application of passive ray tomography to the experimental data yields the current velocity profile in the Straits of Florida, which agrees with independent measurements within the inversion error limit.

  19. Passive localization in the deep ocean based on cross-correlation function matching.

    PubMed

    Lei, Zhixiong; Yang, Kunde; Ma, Yuanliang

    2016-06-01

    Passive localization of a sound source in the deep ocean is investigated in this study. The source can be localized by taking advantage of a cross-correlation function matching technique. When a two-sensor vertical array is used in the deep ocean, two types of side lobe curves appear in the ambiguity surface of the localization. The side lobe curves are analytically expressed and they are then used as indicators of the localization result instead of the scanning point with the maximum power. Simulation and experiment demonstrate the performance of the proposed passive localization method.

  20. The matched-lag filter: detecting broadband multipath signals with auto- and cross-correlation functions.

    PubMed

    Spiesberger, J L

    2001-05-01

    Signal detection is considered for uncertain noise variance and a broadband source of unknown waveform and emission time. The signal travels to the receivers along paths with unknown delays. Using a new "matched-lag filter," the presence or absence of the signal is estimated from the auto- and cross-correlation functions of the receptions. Like a matched filter, correlation functions provide the first stage of gain in signal-to-noise ratio because the paths are assumed to be partially coherent. The second stage achieves additional gain by searching only over physically possible arrangements of signals in the auto- and cross-correlation functions while excluding forbidden arrangements. These stages enable the matched-lag filter to behave like a matched filter within a matched filter. In an ideal case, simulations of the matched-lag filter yield probabilities of detection that are, with one and two receivers, 4.1 and 366 times, respectively, that obtained from the conventional energy detector at a false-alarm probability of 0.001. The matched-lag filter has applications to wireless communications and the detection of acoustic signals from animals, vehicles, ships, and nuclear blasts. The matched-lag filter more completely describes signal structure than stochastic detection and communication theories whose specified auto-correlation function does not prohibit forbidden arrangements.

  1. Time Reversal Mirrors and Cross Correlation Functions in Acoustic Wave Propagation

    NASA Astrophysics Data System (ADS)

    Fishman, Louis; Jonsson, B. Lars G.; de Hoop, Maarten V.

    2009-03-01

    In time reversal acoustics (TRA), a signal is recorded by an array of transducers, time reversed, and then retransmitted into the configuration. The retransmitted signal propagates back through the same medium and retrofocuses on the source that generated the signal. If the transducer array is a single, planar (flat) surface, then this configuration is referred to as a planar, one-sided, time reversal mirror (TRM). In signal processing, for example, in active-source seismic interferometry, the measurement of the wave field at two distinct receivers, generated by a common source, is considered. Cross correlating these two observations and integrating the result over the sources yield the cross correlation function (CCF). Adopting the TRM experiments as the basic starting point and identifying the kinematically correct correspondences, it is established that the associated CCF signal processing constructions follow in a specific, infinite recording time limit. This perspective also provides for a natural rationale for selecting the Green's function components in the TRM and CCF expressions. For a planar, one-sided, TRM experiment and the corresponding CCF signal processing construction, in a three-dimensional homogeneous medium, the exact expressions are explicitly calculated, and the connecting limiting relationship verified. Finally, the TRM and CCF results are understood in terms of the underlying, governing, two-way wave equation, its corresponding time reversal invariance (TRI) symmetry, and the absence of TRI symmetry in the associated one-way wave equations, highlighting the role played by the evanescent modal contributions.

  2. Measurement of the dipole in the cross-correlation function of galaxies

    NASA Astrophysics Data System (ADS)

    Gaztanaga, Enrique; Bonvin, Camille; Hui, Lam

    2017-01-01

    It is usually assumed that in the linear regime the two-point correlation function of galaxies contains only a monopole, quadrupole and hexadecapole. Looking at cross-correlations between different populations of galaxies, this turns out not to be the case. In particular, the cross-correlations between a bright and a faint population of galaxies contain also a dipole. In this paper we present the first attempt to measure this dipole. We discuss the four types of effects that contribute to the dipole: relativistic distortions, evolution effect, wide-angle effect and large-angle effect. We show that the first three contributions are intrinsic anti-symmetric contributions that do not depend on the choice of angle used to measure the dipole. On the other hand the large-angle effect appears only if the angle chosen to extract the dipole breaks the symmetry of the problem. We show that the relativistic distortions, the evolution effect and the wide-angle effect are too small to be detected in the LOWz and CMASS sample of the BOSS survey. On the other hand with a specific combination of angles we are able to measure the large-angle effect with high significance. We emphasise that this large-angle dipole does not contain new physical information, since it is just a geometrical combination of the monopole and the quadrupole. However this measurement, which is in excellent agreement with theoretical predictions, validates our method for extracting the dipole from the two-point correlation function and it opens the way to the detection of relativistic effects in future surveys like e.g. DESI.

  3. Finding the right cross-correlation peak for locating sounds in multipath environments with a fourth-moment function

    PubMed

    Spiesberger

    2000-09-01

    To locate calling animals in reverberant environments from recordings on widely separated receivers, a fourth-moment "Augmented-Template Correlation Function" (ATCF) helps identify which of many peaks in each cross-correlation function is that corresponding to the difference in travel times for the first arrivals (reference-lag). This peak may not be the largest. The ATCF, by providing an approximate correlation between auto- and cross-correlation functions, can be orders of magnitude more efficient in selecting the reference-lag than the alternative of randomly selecting peaks. The ATCF's efficacy increases with the number of paths and their signal-to-noise ratios.

  4. Studies in astronomical time series analysis. III - Fourier transforms, autocorrelation functions, and cross-correlation functions of unevenly spaced data

    NASA Technical Reports Server (NTRS)

    Scargle, Jeffrey D.

    1989-01-01

    This paper develops techniques to evaluate the discrete Fourier transform (DFT), the autocorrelation function (ACF), and the cross-correlation function (CCF) of time series which are not evenly sampled. The series may consist of quantized point data (e.g., yes/no processes such as photon arrival). The DFT, which can be inverted to recover the original data and the sampling, is used to compute correlation functions by means of a procedure which is effectively, but not explicitly, an interpolation. The CCF can be computed for two time series not even sampled at the same set of times. Techniques for removing the distortion of the correlation functions caused by the sampling, determining the value of a constant component to the data, and treating unequally weighted data are also discussed. FORTRAN code for the Fourier transform algorithm and numerical examples of the techniques are given.

  5. Studies in astronomical time series analysis. III - Fourier transforms, autocorrelation functions, and cross-correlation functions of unevenly spaced data

    NASA Technical Reports Server (NTRS)

    Scargle, Jeffrey D.

    1989-01-01

    This paper develops techniques to evaluate the discrete Fourier transform (DFT), the autocorrelation function (ACF), and the cross-correlation function (CCF) of time series which are not evenly sampled. The series may consist of quantized point data (e.g., yes/no processes such as photon arrival). The DFT, which can be inverted to recover the original data and the sampling, is used to compute correlation functions by means of a procedure which is effectively, but not explicitly, an interpolation. The CCF can be computed for two time series not even sampled at the same set of times. Techniques for removing the distortion of the correlation functions caused by the sampling, determining the value of a constant component to the data, and treating unequally weighted data are also discussed. FORTRAN code for the Fourier transform algorithm and numerical examples of the techniques are given.

  6. Influence of the noise sources motion on the estimated Green's functions from ambient noise cross-correlations.

    PubMed

    Sabra, Karim G

    2010-06-01

    It has been demonstrated theoretically and experimentally that an estimate of the Green's function between two receivers can be obtained by cross-correlating acoustic (or elastic) ambient noise recorded at these two receivers. Coherent wavefronts emerge from the noise cross-correlation time function due to the accumulated contributions over time from noise sources whose propagation path pass through both receivers. Previous theoretical studies of the performance of this passive imaging technique have assumed that no relative motion between noise sources and receivers occurs. In this article, the influence of noise sources motion (e.g., aircraft or ship) on this passive imaging technique was investigated theoretically in free space, using a stationary phase approximation, for stationary receivers. The theoretical results were extended to more complex environments, in the high-frequency regime, using first-order expansions of the Green's function. Although sources motion typically degrades the performance of wideband coherent processing schemes, such as time-delay beamforming, it was found that the Green's function estimated from ambient noise cross-correlations are not expected to be significantly affected by the Doppler effect, even for supersonic sources. Numerical Monte-Carlo simulations were conducted to confirm these theoretical predictions for both cases of subsonic and supersonic moving sources.

  7. A GROUP-GALAXY CROSS-CORRELATION FUNCTION ANALYSIS IN zCOSMOS

    SciTech Connect

    Knobel, C.; Lilly, S. J.; Carollo, C. M.; Caputi, K.; Contini, T.; Kneib, J.-P.; Le Fevre, O.; Renzini, A.; Scodeggio, M.; Franzetti, P.; Garilli, B.; Zamorani, G.; Bardelli, S.; Bolzonella, M.; Bongiorno, A.; Cucciati, O.; Iovino, A.; De la Torre, S.; De Ravel, L.; and others

    2012-08-10

    We present a group-galaxy cross-correlation analysis using a group catalog produced from the 16,500 spectra from the optical zCOSMOS galaxy survey. Our aim is to perform a consistency test in the redshift range 0.2 {<=} z {<=} 0.8 between the clustering strength of the groups and mass estimates that are based on the richness of the groups. We measure the linear bias of the groups by means of a group-galaxy cross-correlation analysis and convert it into mass using the bias-mass relation for a given cosmology, checking the systematic errors using realistic group and galaxy mock catalogs. The measured bias for the zCOSMOS groups increases with group richness as expected by the theory of cosmic structure formation and yields masses that are reasonably consistent with the masses estimated from the richness directly, considering the scatter that is obtained from the 24 mock catalogs. Some exceptions are the richest groups at high redshift (estimated to be more massive than 10{sup 13.5} M{sub Sun }), for which the measured bias is significantly larger than for any of the 24 mock catalogs (corresponding to a 3{sigma} effect), which is attributed to the extremely large structure that is present in the COSMOS field at z {approx} 0.7. Our results are in general agreement with previous studies that reported unusually strong clustering in the COSMOS field.

  8. Cross-correlation beamforming

    NASA Astrophysics Data System (ADS)

    Ruigrok, Elmer; Gibbons, Steven; Wapenaar, Kees

    2016-10-01

    An areal distribution of sensors can be used for estimating the direction of incoming waves through beamforming. Beamforming may be implemented as a phase-shifting and stacking of data recorded on the different sensors (i.e., conventional beamforming). Alternatively, beamforming can be applied to cross-correlations between the waveforms on the different sensors. We derive a kernel for beamforming cross-correlated data and call it cross-correlation beamforming (CCBF). We point out that CCBF has slightly better resolution and aliasing characteristics than conventional beamforming. When auto-correlations are added to CCBF, the array response functions are the same as for conventional beamforming. We show numerically that CCBF is more resilient to non-coherent noise. Furthermore, we illustrate that with CCBF individual receiver-pairs can be removed to improve mapping to the slowness domain. An additional flexibility of CCBF is that cross-correlations can be time-windowed prior to beamforming, e.g., to remove the directionality of a scattered wavefield. The observations on synthetic data are confirmed with field data from the SPITS array (Svalbard). Both when beamforming an earthquake arrival and when beamforming ambient noise, CCBF focuses more of the energy to a central beam. Overall, the main advantage of CCBF is noise suppression and its flexibility to remove station pairs that deteriorate the signal-related beampower.

  9. When can Empirical Green Functions be computed from Noise Cross-Correlations? Hints from different Geographical and Tectonic environments

    NASA Astrophysics Data System (ADS)

    Matos, Catarina; Silveira, Graça; Custódio, Susana; Domingues, Ana; Dias, Nuno; Fonseca, João F. B.; Matias, Luís; Krueger, Frank; Carrilho, Fernando

    2014-05-01

    Noise cross-correlations are now widely used to extract Green functions between station pairs. But, do all the cross-correlations routinely computed produce successful Green Functions? What is the relationship between noise recorded in a couple of stations and the cross-correlation between them? During the last decade, we have been involved in the deployment of several temporary dense broadband (BB) networks within the scope of both national projects and international collaborations. From 2000 to 2002, a pool of 8 BB stations continuously operated in the Azores in the scope of the Memorandum of Understanding COSEA (COordinated Seismic Experiment in the Azores). Thanks to the Project WILAS (West Iberia Lithosphere and Astenosphere Structure, PTDC/CTE-GIX/097946/2008) we temporarily increased the number of BB deployed in mainland Portugal to more than 50 (permanent + temporary) during the period 2010 - 2012. In 2011/12 a temporary pool of 12 seismometers continuously recorded BB data in the Madeira archipelago, as part of the DOCTAR (Deep Ocean Test Array Experiment) project. Project CV-PLUME (Investigation on the geometry and deep signature of the Cape Verde mantle plume, PTDC/CTE-GIN/64330/2006) covered the archipelago of Cape Verde, North Atlantic, with 40 temporary BB stations in 2007/08. Project MOZART (Mozambique African Rift Tomography, PTDC/CTE-GIX/103249/2008), covered Mozambique, East Africa, with 30 temporary BB stations in the period 2011 - 2013. These networks, located in very distinct geographical and tectonic environments, offer an interesting opportunity to study seasonal and spatial variations of noise sources and their impact on Empirical Green functions computed from noise cross-correlation. Seismic noise recorded at different seismic stations is evaluated by computation of the probability density functions of power spectral density (PSD) of continuous data. To assess seasonal variations of ambient noise sources in frequency content, time-series of

  10. Damage detection of metro tunnel structure through transmissibility function and cross correlation analysis using local excitation and measurement

    NASA Astrophysics Data System (ADS)

    Feng, Lei; Yi, Xiaohua; Zhu, Dapeng; Xie, Xiongyao; Wang, Yang

    2015-08-01

    In a modern metropolis, metro rail systems have become a dominant mode for mass transportation. The structural health of a metro tunnel is closely related to public safety. Many vibration-based techniques for detecting and locating structural damage have been developed in the past several decades. However, most damage detection techniques and validation tests are focused on bridge and building structures; very few studies have been reported on tunnel structures. Among these techniques, transmissibility function and cross correlation analysis are two well-known diagnostic approaches. The former operates in frequency domain and the latter in time domain. Both approaches can be applied to detect and locate damage through acceleration data obtained from sensor arrays. Furthermore, the two approaches can directly utilize structural response data without requiring excitation measurement, which offers advantages in field testing on a large structure. In this research, a numerical finite element model of a metro tunnel is built and different types of structural defects are introduced at multiple locations of the tunnel. Transmissibility function and cross correlation analysis are applied to perform structural damage detection and localization, based on simulated structural vibration data. Numerical results demonstrate that the introduced defects can be successfully identified and located. The sensitivity and feasibility of the two approaches have been verified when sufficient distribution of measurement locations is available. Damage detection results of the two different approaches are compared and discussed.

  11. Shot noise cross-correlation functions and cross spectra - Implications for models of QPO X-ray sources

    NASA Technical Reports Server (NTRS)

    Shibazaki, N.; Elsner, R. F.; Bussard, R. W.; Ebisuzaki, T.; Weisskopf, M. C.

    1988-01-01

    The cross-correlation functions (CCFs) and cross spectra expected for quasi-periodic oscillation (QPO) shot noise models are calculated under various assumptions, and the results are compared to observations. Effects due to possible coherence of the QPO oscillations are included. General formulas for the cross spectrum, the cross-phase spectrum, and the time-delay spectrum for QPO shot models are calculated and discussed. It is shown that the CCFs, cross spectra, and power spectra observed for Cyg X-e2 imply that the spectrum of the shots evolves with time, with important implications for the interpretation of these functions as well as of observed average energy spectra. The possible origins for the observed hard lags are discussed, and some physical difficulties for the Comptonization model are described. Classes of physical models for QPO sources are briefly addressed, and it is concluded that models involving shot formation at the surface of neutron stars are favored by observation.

  12. Surface wave group velocity in the Osaka sedimentary basin, Japan, estimated using ambient noise cross-correlation functions

    NASA Astrophysics Data System (ADS)

    Asano, Kimiyuki; Iwata, Tomotaka; Sekiguchi, Haruko; Somei, Kazuhiro; Miyakoshi, Ken; Aoi, Shin; Kunugi, Takashi

    2017-08-01

    Inter-station cross-correlation functions estimated using continuous ambient noise or microtremor records were used to extract the seismic wave propagation characteristics of the Osaka sedimentary basin, Japan. Temporary continuous observations were conducted at 15 sites in the Osaka basin between 2011 and 2013. The data were analyzed using seismic interferometry. The target period range was 2-8 s. Cross-correlations between all of the possible station pairs were calculated and stacked to produce a year-long data set, and Rayleigh wave signals in the vertical and radial components and Love wave signals in the transverse component were identified from the results. Simulation of inter-station Green's functions using the finite difference method was conducted to check the performance of the current three-dimensional velocity structure model. The measured time lag between the observed and theoretical Green's functions was less than 2 s for most station pairs, which is less than the wave period of interest in the target frequency range. Group velocity tomography was applied to group delay times estimated by means of multiple filter analysis. The estimated group velocities for longer periods of 5-8 s exhibited spatial variation within the basin, which is consistent with the bedrock depth distribution; however, the group velocities for shorter periods of 2-3 s were almost constant over the studied area. The waveform and group velocity information obtained by seismic interferometry analysis can be useful for future reconstruction of a three-dimensional velocity structure model in the Osaka basin.[Figure not available: see fulltext.

  13. Understanding volatility correlation behavior with a magnitude cross-correlation function

    NASA Astrophysics Data System (ADS)

    Jun, Woo Cheol; Oh, Gabjin; Kim, Seunghwan

    2006-06-01

    We propose an approach for analyzing the basic relation between correlation properties of the original signal and its magnitude fluctuations by decomposing the original signal into its positive and negative fluctuation components. We use this relation to understand the following phenomenon found in many naturally occurring time series: the magnitude of the signal exhibits long-range correlation, whereas the original signal is short-range correlated. The applications of our approach to heart rate variability signals and high-frequency foreign exchange rates reveal that the difference between the correlation properties of the original signal and its magnitude fluctuations is induced by the time organization structure of the correlation function between the magnitude fluctuations of positive and negative components. We show that this correlation function can be described well by a stretched-exponential function and is related to the nonlinearity and the multifractal structure of the signals.

  14. Decomposition of Proteins into Dynamic Units from Atomic Cross-Correlation Functions.

    PubMed

    Calligari, Paolo; Gerolin, Marco; Abergel, Daniel; Polimeno, Antonino

    2017-01-10

    In this article, we present a clustering method of atoms in proteins based on the analysis of the correlation times of interatomic distance correlation functions computed from MD simulations. The goal is to provide a coarse-grained description of the protein in terms of fewer elements that can be treated as dynamically independent subunits. Importantly, this domain decomposition method does not take into account structural properties of the protein. Instead, the clustering of protein residues in terms of networks of dynamically correlated domains is defined on the basis of the effective correlation times of the pair distance correlation functions. For these properties, our method stands as a complementary analysis to the customary protein decomposition in terms of quasi-rigid, structure-based domains. Results obtained for a prototypal protein structure illustrate the approach proposed.

  15. Offshore Southern California lithospheric velocity structure from noise cross-correlation functions

    NASA Astrophysics Data System (ADS)

    Bowden, D. C.; Kohler, M. D.; Tsai, V. C.; Weeraratne, D. S.

    2016-05-01

    A new shear wave velocity model offshore Southern California is presented that images plate boundary deformation including both thickening and thinning of the crustal and mantle lithosphere at the westernmost edge of the North American continent. The Asthenospheric and Lithospheric Broadband Architecture from the California Offshore Region Experiment (ALBACORE) ocean bottom seismometer array, together with 65 stations of the onshore Southern California Seismic Network, is used to measure ambient noise correlation functions and Rayleigh wave dispersion curves which are inverted for 3-D shear wave velocities. The resulting velocity model defines the transition from continental lithosphere to oceanic, illuminating the complex history and deformation in the region. A transition to the present-day strike-slip regime between the Pacific and North American Plates resulted in broad deformation and capture of the now >200 km wide continental shelf. Our velocity model suggests the persistence of the uppermost mantle volcanic processes associated with East Pacific Rise spreading adjacent to the Patton Escarpment, which marks the former subduction of Farallon Plate underneath North America. The most prominent of these seismic structures is a low-velocity anomaly underlying the San Juan Seamount, suggesting ponding of magma at the base of the crust, resulting in thickening and ongoing adjustment of the lithosphere due to the localized loading. The velocity model also provides a robust framework for future earthquake location determinations and ground-shaking simulations for risk estimates.

  16. Dangers and uses of cross-correlation in analyzing time series in perception, performance, movement, and neuroscience: The importance of constructing transfer function autoregressive models.

    PubMed

    Dean, Roger T; Dunsmuir, William T M

    2016-06-01

    Many articles on perception, performance, psychophysiology, and neuroscience seek to relate pairs of time series through assessments of their cross-correlations. Most such series are individually autocorrelated: they do not comprise independent values. Given this situation, an unfounded reliance is often placed on cross-correlation as an indicator of relationships (e.g., referent vs. response, leading vs. following). Such cross-correlations can indicate spurious relationships, because of autocorrelation. Given these dangers, we here simulated how and why such spurious conclusions can arise, to provide an approach to resolving them. We show that when multiple pairs of series are aggregated in several different ways for a cross-correlation analysis, problems remain. Finally, even a genuine cross-correlation function does not answer key motivating questions, such as whether there are likely causal relationships between the series. Thus, we illustrate how to obtain a transfer function describing such relationships, informed by any genuine cross-correlations. We illustrate the confounds and the meaningful transfer functions by two concrete examples, one each in perception and performance, together with key elements of the R software code needed. The approach involves autocorrelation functions, the establishment of stationarity, prewhitening, the determination of cross-correlation functions, the assessment of Granger causality, and autoregressive model development. Autocorrelation also limits the interpretability of other measures of possible relationships between pairs of time series, such as mutual information. We emphasize that further complexity may be required as the appropriate analysis is pursued fully, and that causal intervention experiments will likely also be needed.

  17. Robust time-domain full waveform inversion with normalized zero-lag cross-correlation objective function

    NASA Astrophysics Data System (ADS)

    Liu, Youshan; Teng, Jiwen; Xu, Tao; Wang, Yanghua; Liu, Qinya; Badal, José

    2017-04-01

    In full waveform inversion (FWI) with the least-squares (L2) norm, the direct amplitude matching is never perfect and the accurate estimation of the seismic source strength is not always available. In contrast, the normalized zero-lag cross-correlation objective function relaxes on the amplitude constraints and emphasizes the phase information when measuring the closeness between the simulated and observed data. This FWI method becomes insensitive to differences in amplitude. Based on this property, we investigate the effectiveness and robustness of FWI with the normalized zero-lag cross-correlation function (CFWI) against the noise and unpredictable amplitude of the data that cannot be modelled by the wavefield extrapolation operator. The effectiveness is firstly tested by noise-free data and data contaminated by Gaussian white noise. In addition, CFWI can invert the data set with incorrect source strength when compared with the L2 norm. Moreover, the data set with incorrect source signature illustrates that CFWI is slightly more insensitive to the error in source signature than the L2 norm. However, a source inversion is still needed when the source signature is severely erroneous. With non-Gaussian noise data, such as contaminated by strong ground motion noise and even by spike-type noise, CFWI provides a comparable result with that of the robust Huber norm. Numerical experiments with non-Gaussian noise also indicate that CFWI can suppress noise in data to produce clearer images when compared with the Huber norm. Besides, CFWI is free of the threshold criterion that controls the transition between the L2 and L1 norms used with the Huber and Hybrid norms and therefore free from tedious trial-and-error tests. Several numerical examples support that CFWI is an alternative and reliable inversion method. However, a numerical test with a 1-D initial model confirms that CFWI is more sensitive to the cycle-skipping problem caused by less-accurate initial velocity model

  18. Velocity variations associated with the large 2010 eruption of Merapi volcano, Java, retrieved from seismic multiplets and ambient noise cross-correlation

    NASA Astrophysics Data System (ADS)

    Budi-Santoso, Agus; Lesage, Philippe

    2016-07-01

    We present a study of the seismic velocity variations that occurred in the structure before the large 2010 eruption of Merapi volcano. For the first time to our knowledge, the technique of coda wave interferometry is applied to both families of similar events (multiplets) and to correlation functions of seismic noise. About half of the seismic events recorded at the summit stations belong to one of the ten multiplets identified, including 120 similar events that occurred in the last 20 hr preceding the eruption onset. Daily noise cross-correlation functions (NCF) were calculated for the six pairs of short-period stations available. Using the stretching method, we estimate time-series of apparent velocity variation (AVV) for each multiplet and each pair of stations. No significant velocity change is detected until September 2010. From 10 October to the beginning of the eruption on 26 October, a complex pattern of AVV is observed with amplitude of up to ±1.5 per cent. Velocity decrease is first observed from families of deep events and then from shallow earthquakes. In the same period, AVV with different signs and chronologies are estimated from NCF calculated for various station pairs. The location in the horizontal plane of the velocity perturbations related with the AVV obtained from NCF is estimated by using an approach based on the radiative transfer approximation. Although their spatial resolution is limited, the resulting maps display velocity decrease in the upper part of the edifice in the period 12-25 October. After the eruption onset, the pattern of velocity perturbations is significantly modified with respect to the previous one. We interpret these velocity variations in the framework of a scenario of magmatic intrusion that integrates most observations. The perturbation of the stress field associated with the magma migration can induce both decrease and increase of the seismic velocity of rocks. Thus the detected AVVs can be considered as precursors of

  19. Properties of Noise Cross-Correlation Functions Obtained from a Distributed Acoustic Sensing Array at Garner Valley, California

    DOE PAGES

    Zeng, Xiangfang; Lancelle, Chelsea; Thurber, Clifford; ...

    2017-01-31

    A field test that was conducted at Garner Valley, California, on 11 and 12 September 2013 using distributed acoustic sensing (DAS) to sense ground vibrations provided a continuous overnight record of ambient noise. Furthermore, the energy of ambient noise was concentrated between 5 and 25 Hz, which falls into the typical traffic noise frequency band. A standard procedure (Bensen et al., 2007) was adopted to calculate noise cross-correlation functions (NCFs) for 1-min intervals. The 1-min-long NCFs were stacked using the time–frequency domain phase-weighted-stacking method, which significantly improves signal quality. The obtained NCFs were asymmetrical, which was a result of themore » nonuniform distributed noise sources. A precursor appeared on NCFs along one segment, which was traced to a strong localized noise source or a scatterer at a nearby road intersection. NCF for the radial component of two surface accelerometers along a DAS profile gave similar results to those from DAS channels. Here, we calculated the phase velocity dispersion from DAS NCFs using the multichannel analysis of surface waves technique, and the result agrees with active-source results. We then conclude that ambient noise sources and the high spatial sampling of DAS can provide the same subsurface information as traditional active-source methods.« less

  20. Intrinsic Noise Level of Noise Cross-Correlation Functions and its Implication to Source Population of Ambient noises

    NASA Astrophysics Data System (ADS)

    Chen, Ying-Nien; Gung, Yuancheng; Chiao, Ling-Yun; Rhie, Junkee

    2017-01-01

    SUMMARYWe present a quantitative procedure to evaluate the intrinsic noise level (INL) of the noise <span class="hlt">cross-correlation</span> <span class="hlt">function</span> (NCF). The method is applied to realistic NCFs derived from the continuous data recorded by the seismic arrays in Taiwan and Korea. The obtained temporal evolution of NCF noise level follows fairly the prediction of the theoretical formulation, confirming the feasibility of the method. We then apply the obtained INL to the assessment of data quality and the source characteristics of ambient noise. We show that the INL-based signal-to-noise ratio provides an exact measure for the true noise level within the NCF and better resolving power for the NCF quality, and such measurement can be implemented to any time windows of the NCFs to evaluate the quality of overtones or coda waves. Moreover, since NCF amplitudes are influenced by both the population and excitation strengths of noises, while INL is primarily sensitive to the overall source population, with information from both measurements, we may better constrain the source characteristics of seismic ambient noises.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li class="active"><span>2</span></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_2 --> <div id="page_3" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="41"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.470..688B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.470..688B"><span>Improving Fisher matrix forecasts for galaxy surveys: window <span class="hlt">function</span>, bin <span class="hlt">cross-correlation</span> and bin redshift uncertainty</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bailoni, Alberto; Spurio Mancini, Alessio; Amendola, Luca</p> <p>2017-09-01</p> <p>The Fisher matrix is a widely used tool to forecast the performance of future experiments and approximate the likelihood of large data sets. Most of the forecasts for cosmological parameters in galaxy clustering studies rely on the Fisher matrix approach for large-scale experiments like DES, Euclid or SKA. Here, we improve upon the standard method by taking into account three effects: the finite window <span class="hlt">function</span>, the correlation between redshift bins and the uncertainty on the bin redshift. The first two effects are negligible only in the limit of infinite surveys. The third effect, in contrast, is negligible for infinitely small bins. Here, we show how to take into account these effects and what the impact on forecasts of a Euclid-type experiment will be. The main result of this paper is that the windowing and the bin <span class="hlt">cross-correlation</span> induce a considerable change in the forecasted errors, of the order of 10-30 per cent for most cosmological parameters, while the redshift bin uncertainty can be neglected for bins smaller than Δz = 0.1 roughly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OLEB...46..487M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OLEB...46..487M"><span>Reflected Light from Giant Planets in Habitable Zones: Tapping into the Power of the <span class="hlt">Cross-Correlation</span> <span class="hlt">Function</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martins, J. H. C.; Santos, N. C.; Figueira, P.; Melo, C.</p> <p>2016-11-01</p> <p>The direct detection of reflected light from exoplanets is an excellent probe for the characterization of their atmospheres. The greatest challenge for this task is the low planet-to-star flux ratio, which even in the most favourable case is of the order of 10-4 in the optical. This ratio decreases even more for planets in their host's habitable zone, typically lower than 10-7. To reach the signal-to-noise level required for such detections, we propose to unleash the power of the <span class="hlt">Cross</span> <span class="hlt">Correlation</span> <span class="hlt">Function</span> in combination with the collecting power of next generation observing facilities. The technique we propose has already yielded positive results by detecting the reflected spectral signature of 51 Pegasi b (see Martins et al. 2015). In this work, we attempted to infer the number of hours required for the detection of several planets in their host's habitable zone using the aforementioned technique from theoretical EELT observations. Our results show that for 5 of the selected planets it should be possible to directly recover their reflected spectral signature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4254874','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4254874"><span>Joint <span class="hlt">cross-correlation</span> analysis reveals complex, time-dependent <span class="hlt">functional</span> relationship between cortical neurons and arm electromyograms</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhuang, Katie Z.; Lebedev, Mikhail A.</p> <p>2014-01-01</p> <p>Correlation between cortical activity and electromyographic (EMG) activity of limb muscles has long been a subject of neurophysiological studies, especially in terms of corticospinal connectivity. Interest in this issue has recently increased due to the development of brain-machine interfaces with output signals that mimic muscle force. For this study, three monkeys were implanted with multielectrode arrays in multiple cortical areas. One monkey performed self-timed touch pad presses, whereas the other two executed arm reaching movements. We analyzed the dynamic relationship between cortical neuronal activity and arm EMGs using a joint <span class="hlt">cross-correlation</span> (JCC) analysis that evaluated trial-by-trial correlation as a <span class="hlt">function</span> of time intervals within a trial. JCCs revealed transient correlations between the EMGs of multiple muscles and neural activity in motor, premotor and somatosensory cortical areas. Matching results were obtained using spike-triggered averages corrected by subtracting trial-shuffled data. Compared with spike-triggered averages, JCCs more readily revealed dynamic changes in cortico-EMG correlations. JCCs showed that correlation peaks often sharpened around movement times and broadened during delay intervals. Furthermore, JCC patterns were directionally selective for the arm-reaching task. We propose that such highly dynamic, task-dependent and distributed relationships between cortical activity and EMGs should be taken into consideration for future brain-machine interfaces that generate EMG-like signals. PMID:25210153</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27029795','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27029795"><span>Reflected Light from Giant Planets in Habitable Zones: Tapping into the Power of the <span class="hlt">Cross-Correlation</span> <span class="hlt">Function</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Martins, J H C; Santos, N C; Figueira, P; Melo, C</p> <p>2016-11-01</p> <p>The direct detection of reflected light from exoplanets is an excellent probe for the characterization of their atmospheres. The greatest challenge for this task is the low planet-to-star flux ratio, which even in the most favourable case is of the order of 10(-4) in the optical. This ratio decreases even more for planets in their host's habitable zone, typically lower than 10(-7). To reach the signal-to-noise level required for such detections, we propose to unleash the power of the <span class="hlt">Cross</span> <span class="hlt">Correlation</span> <span class="hlt">Function</span> in combination with the collecting power of next generation observing facilities. The technique we propose has already yielded positive results by detecting the reflected spectral signature of 51 Pegasi b (see Martins et al. 2015). In this work, we attempted to infer the number of hours required for the detection of several planets in their host's habitable zone using the aforementioned technique from theoretical EELT observations. Our results show that for 5 of the selected planets it should be possible to directly recover their reflected spectral signature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.tmp.1605V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.tmp.1605V"><span>A Measurement of the Galaxy Group-Thermal Sunyaev-Zel'dovich Effect <span class="hlt">Cross-Correlation</span> <span class="hlt">Function</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vikram, Vinu; Lidz, Adam; Jain, Bhuvnesh</p> <p>2016-12-01</p> <p>Stacking cosmic microwave background (CMB) maps around known galaxy clusters and groups provides a powerful probe of the distribution of hot gas in these systems via the Sunyaev-Zel'dovich (SZ) effect. A stacking analysis allows one to detect the average SZ signal around low mass halos, to extend measurements out to large scales and measure the redshift-dependence of the SZ background. Motivated by these exciting prospects, we measure the two-point <span class="hlt">cross-correlation</span> <span class="hlt">function</span> between ˜380, 000 galaxy groups (at z = 0.01 - 0.2) from the Sloan Digital Sky Survey (SDSS) and Compton-y parameter maps constructed by the Planck collaboration. We find statistically significant correlations in each of six separate mass bins, with halo masses ranging from 1011.5 - 15.5M⊙/h. We compare with halo models of the SZ signal, which describe the stacked measurement in terms of one-halo and two-halo contributions. The one-halo term quantifies the average pressure profile around the groups in a mass bin, while the two-halo term describes the contribution of correlated neighbouring halos. For the massive groups we find clear evidence for the one- and two-halo regimes, while groups with mass below 1013M⊙/h are dominated by the two-halo term given the resolution of Planck data. We use the signal in the two-halo regime to determine the bias-weighted electron pressure of the universe: <bPe> = 1.50 ± 0.226 × 10-7 keV cm-3 (1-σ) at z ≈ 0.15.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.467.2315V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.467.2315V"><span>A Measurement of the Galaxy Group-Thermal Sunyaev-Zel'dovich Effect <span class="hlt">Cross-Correlation</span> <span class="hlt">Function</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vikram, Vinu; Lidz, Adam; Jain, Bhuvnesh</p> <p>2017-05-01</p> <p>Stacking cosmic microwave background maps around known galaxy clusters and groups provides a powerful probe of the distribution of hot gas in these systems via the Sunyaev-Zel'dovich (SZ) effect. A stacking analysis allows one to detect the average SZ signal around low-mass haloes, to extend measurements out to large scales and measure the redshift dependence of the SZ background. Motivated by these exciting prospects, we measure the two-point <span class="hlt">cross-correlation</span> <span class="hlt">function</span> between ˜380 000 galaxy groups (at z = 0.01-0.2) from the Sloan Digital Sky Survey and Compton-y parameter maps constructed by the Planck collaboration. We find statistically significant correlations in each of six separate mass bins, with halo masses ranging from 1011.5 to 1015.5 M⊙ h-1. We compare with halo models of the SZ signal, which describe the stacked measurement in terms of one-halo and two-halo contributions. The one-halo term quantifies the average pressure profile around the groups in a mass bin, while the two-halo term describes the contribution of correlated neighbouring haloes. For the massive groups, we find clear evidence for the one- and two-halo regimes, while groups with mass below 1013 M⊙ h-1 are dominated by the two-halo term, given the resolution of Planck data. We use the signal in the two-halo regime to determine the bias-weighted electron pressure of the Universe: <bPe> = 1.50 ± 0.226 × 10-7 keV cm-3 (1σ) at z ≈ 0.15.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S41B2720Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S41B2720Z"><span>Properties of Noise <span class="hlt">Cross</span> <span class="hlt">Correlation</span> <span class="hlt">Functions</span> Obtained from a Distributed Acoustic Sensing (DAS) Array at Garner Valley, California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zeng, X.; Lancelle, C.; Thurber, C. H.; Fratta, D.; Wang, H. F.; Chalari, A.; Clarke, A.</p> <p>2015-12-01</p> <p>The field test of Distributed Acoustic Sensing (DAS) conducted at Garner Valley, California on September 11-12, 2013 provided a continuous overnight record of ambient noise. The DAS array recorded ground motions every one meter of optical cable that was arranged approximately in the shape of a rectangle with dimensions of 160 m by 80 m. The long dimension of the array was adjacent to a state highway. Three hours of record were used to compute noise <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> (NCFs) in one-minute windows. The trace from each sensor channel was pre-processed by downsampling to 200 Hz, followed by normalization in the time-domain and bandpass filtering between 2 and 20 Hz (Bensen et al., 2007). The one-minute NCFs were then stacked using the time-frequency domain phase-weighted stacking method (Schimmel & Gallart, 2007). The NCFs between channels were asymmetrical reflecting the direction of traffic noise. The group velocities were found using the frequency-time analysis method. The energy was concentrated between 5 and 15 Hz, which falls into the typical traffic noise frequency band. The resulting velocities were between 100 and 300 m/s for frequencies between 10 and 20 Hz, which are in the same range as described in the results for surface-wave dispersion obtained using an active source for the same site (Lancelle et al., 2015). The group velocity starts to decrease for frequencies greater than ~10 Hz, which was expected on the basis of a previous shear-wave velocity model (Steidl et al., 1996). Then, the phase velocity was calculated using the multichannel analysis of surface wave technique (MASW - Park et al., 1999) with 114 NCFs spaced one meter apart. The resulting dispersion curve between 5 and 15 Hz gave phase velocities that ranged from approximately 170 m/s at 15 Hz to 250 m/s at 5 Hz. These results are consistent with other results of active-source DAS and seismometer records obtained at the Garner Valley site (e.g., Stokoe et al. 2004). This analysis is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15370359','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15370359"><span><span class="hlt">Functional</span> brain imaging and the induction of traumatic recall: a <span class="hlt">cross-correlational</span> review between neuroimaging and hypnosis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vermetten, Eric; Douglas Bremner, J</p> <p>2004-07-01</p> <p>The behavioral and psychophysiological alterations during recall in patients with trauma disorders often resemble phenomena that are seen in hypnosis. In studies of emotional recall as well as in neuroimaging studies of hypnotic processes similar brain structures are involved: thalamus, hippocampus, amygdala, medial prefrontal cortex, anterior cingulate cortex. This paper focuses on <span class="hlt">cross-correlations</span> in traumatic recall and hypnotic responses and reviews correlations between the involvement of brain structures in traumatic recall and processes that are involved in hypnotic responsiveness. To further improve uniformity of results of brain imaging specifically for traumatic recall studies, attention is needed for standardization of hypnotic variables, isolation of the emotional process of interest (state),and assessment of trait-related differences.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1377365-baryon-acoustic-oscillations-from-complete-sdss-iii-ly-quasar-cross-correlation-function','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1377365-baryon-acoustic-oscillations-from-complete-sdss-iii-ly-quasar-cross-correlation-function"><span>Baryon acoustic oscillations from the complete SDSS-III Lyα-quasar <span class="hlt">cross-correlation</span> <span class="hlt">function</span> at z = 2.4</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>du Mas des Bourboux, Helion; Le Goff, Jean-Marc; Blomqvist, Michael; ...</p> <p>2017-08-08</p> <p>We present a measurement of baryon acoustic oscillations (BAO) in the <span class="hlt">cross-correlation</span> of quasars with the Lyα-forest flux-transmission at a mean redshift z = 2.40. The measurement uses the complete SDSS-III data sample: 168,889 forests and 234,367 quasars from the SDSS Data Release DR12. In addition to the statistical improvement on our previous study using DR11, we have implemented numerous improvements at the analysis level allowing a more accurate measurement of this <span class="hlt">cross-correlation</span>. We also developed the first simulations of the <span class="hlt">cross-correlation</span> allowing us to test different aspects of our data analysis and to search for potential systematic errors inmore » the determination of the BAO peak position. We measure the two ratios DH(z = 2.40)=rd = 9.01 ± 0.36 and DM(z = 2.40)=rd = 35.7 ±1.7, where the errors include marginalization over the non-linear velocity of quasars and the metal - quasar <span class="hlt">cross-correlation</span> contribution, among other effects. These results are within 1.8σ of the prediction of the flat-ΛCDM model describing the observed CMB anisotropies.We combine this study with the Lyα-forest auto-correlation <span class="hlt">function</span> (Bautista et al. 2017), yielding DH(z = 2.40)=rd = 8.94 ± 0.22 and DM(z = 2.40)=rd = 36.6 ± 1.2, within 2.3σ of the same flat-ΛCDM model.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19457766','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19457766"><span>Stress during simulated emergency transportation in a rescue helicopter: <span class="hlt">cross-correlation</span> between stress hormones, vital <span class="hlt">functions</span> and subjective well-being.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Witzel, K; Elzer, M; Koch, Horst J</p> <p>2009-06-01</p> <p>Vital <span class="hlt">functions</span> and stress hormone levels during simulated emergency helicopter transport in healthy volunteers. Twenty-three volunteers were subjected to a simulated 15 minute rescue helicopter transport. We determined vital <span class="hlt">functions</span>, ACTH, cortisol and prolactin during the flight and filled in a standardized questionnaire before and after the flight. Data were analysed descriptively, by means of cross tabulation, Spearman rank correlation and <span class="hlt">cross-correlation</span> technique. During take-off we recorded a significant increase of vital parameters such as heart rate. Prolactin concentration rose slightly after the start. Maximum cortisol and ACTH levels were found before take-off and then they decreased gradually. As expected, ACTH and cortisol <span class="hlt">cross-correlated</span> significantly without any relevant time lag. Test items showed a feeling of fear and concern before take off. After the flight the volunteers reported having less stress than expected. Particularly, diastolic blood pressure and prolactin levels were markedly associated with questionnaire items such as behaviour of the staff or nausea. Heart rate significantly correlated with anxiety scores. Helicopter transportation induced a marked stress reaction in healthy volunteers, which speaks in favour of smooth transports in modern helicopters and adequate behaviour towards the patient of the staff.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24089252','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24089252"><span>Optimization and extraction of <span class="hlt">functional</span> information from in vitro flow models using dual-beam spectral-domain optical coherence tomography <span class="hlt">cross-correlation</span> analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Daly, Susan M; Silien, Christophe; Leahy, Martin J</p> <p>2013-10-01</p> <p>As in vivo flow behavior can be pulsatile, intermittent, and/or otherwise changeable with time, the ability to provide clinicians with a means of real-time visualization and <span class="hlt">functional</span> assessment of structures is of particular importance. The discernment of pulsatile flow behavior using a dual-beam spectral domain optical coherence tomography system (db-SdOCT) by quasi-simultaneous measurement by two planes of illumination is demonstrated. By <span class="hlt">cross-correlation</span> analysis, it is possible to compute velocity metrics pertaining to flowing particle motion, without a priori angular knowledge. This is the first application of <span class="hlt">cross-correlation</span>-based dynamic assessment for the extraction of pulsatile behavior in an in vitro environment using an optimized db-SdOCT system. The experimental results outlined have shown the db-SdOCT system and its associated algorithms to be successful in the discernment of intermittent pulsatile flow behavior in in vitro models, concurrent to yielding velocity values in good agreement with that of the applied flow rate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoJI.210..210V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoJI.210..210V"><span><span class="hlt">Retrieving</span> impulse response <span class="hlt">function</span> amplitudes from the ambient seismic field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Viens, Loïc; Denolle, Marine; Miyake, Hiroe; Sakai, Shin'ichi; Nakagawa, Shigeki</p> <p>2017-07-01</p> <p>Seismic interferometry is now widely used to <span class="hlt">retrieve</span> the impulse response <span class="hlt">function</span> of the Earth between two distant seismometers. The phase information has been the focus of most passive imaging studies, as conventional seismic tomography uses traveltime measurements. The amplitude information, however, is harder to interpret because it strongly depends on the distribution of ambient seismic field sources and on the multitude of processing methods. Our study focuses on the latter by comparing the amplitudes of the impulse response <span class="hlt">functions</span> calculated between seismic stations in the Kanto sedimentary basin, Japan, using several processing techniques. This region provides a unique natural laboratory to test the reliability of the amplitudes with complex wave propagation through the basin, and dense observations from the Metropolitan Seismic Observation network. We compute the impulse response <span class="hlt">functions</span> using the <span class="hlt">cross</span> <span class="hlt">correlation</span>, coherency and deconvolution techniques of the raw ambient seismic field and the <span class="hlt">cross</span> <span class="hlt">correlation</span> of 1-bit normalized data. To validate the amplitudes of the impulse response <span class="hlt">functions</span>, we use a shallow Mw 5.8 earthquake that occurred on the eastern edge of Kanto Basin and close to a station that is used as the virtual source. Both S and surface waves are <span class="hlt">retrieved</span> in the causal part of the impulse response <span class="hlt">functions</span> computed with all the different techniques. However, the amplitudes obtained from the deconvolution method agree better with those of the earthquake. Despite the expected wave attenuation due to the soft sediments of the Kanto Basin, seismic amplification caused by the basin geometry dominates the amplitudes of S and surface waves and is captured by the ambient seismic field. To test whether or not the anticausal part of the impulse response <span class="hlt">functions</span> from deconvolution also contains reliable amplitude information, we use another virtual source located on the western edge of the basin. We show that the surface wave amplitudes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24675604','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24675604"><span>Structure determination from powder data without prior indexing, using a similarity measure based on <span class="hlt">cross-correlation</span> <span class="hlt">functions</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Habermehl, Stefan; Mörschel, Philipp; Eisenbrandt, Pierre; Hammer, Sonja M; Schmidt, Martin U</p> <p>2014-04-01</p> <p>A method to refine organic crystal structures from powder diffraction data with incorrect lattice parameters has been developed. The method is based on the similarity measure developed by de Gelder et al. [J. Comput. Chem. (2001), 22, 273-289], using the cross- and auto-correlation <span class="hlt">functions</span> of a simulated and an experimental powder pattern. The lattice parameters, molecular position, molecular orientation and selected intramolecular degrees of freedom are optimized until the similarity measure reaches a maximum; subsequently, a Rietveld refinement is carried out. The program FIDEL (FIt with DEviating Lattice parameters) implements this method. The procedure is also suitable for unindexed powder data, powder diagrams of very low quality and powder diagrams of non-phase-pure samples. Various applications are shown, including structure determinations from powder data using crystal structure predictions by standard force-field methods. Other useful applications include the automatic structure determination from powder data starting from the crystal structures of isostructural compounds (e.g. a solvate, hydrate or chemical derivative), or from crystal data measured at a different temperature or pressure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1712176F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1712176F"><span>Identifying apparent velocity changes in <span class="hlt">cross</span> <span class="hlt">correlated</span> microseism noise data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Friderike Volk, Meike; Bean, Christopher; Lokmer, Ivan; Pérez, Nemesio; Ibáñez, Jesús</p> <p>2015-04-01</p> <p>Currently there is a strong interest of using <span class="hlt">cross</span> <span class="hlt">correlation</span> of ambient noise to <span class="hlt">retrieve</span> Green's <span class="hlt">functions</span>. These are usually used to calculate the seismic wave velocity of the subsurface and therefore can be used for subsurface imaging or monitoring of various geological settings where we expect rapid velocity changes (e.g. reservoirs or volcanoes). The assumption of this method is that the wavefields which are correlated must be diffuse. This criterion is fulfilled if the ambient noise sources are uniformly distributed or the scattering in the medium is high enough to mitigate any source directivity. The location of the sources is usually unknown and it can change in time. These temporal and spatial variations of the microseism noise sources may lead to changes in the <span class="hlt">retrieved</span> Green's <span class="hlt">functions</span>, and so, to the apparent changes in seismic wave velocities. To further investigate the apparent changes in Green's <span class="hlt">functions</span> we undertook an active seismic experiment in Tenerife lasting three months. A small airgun was used as an active source and was shooting repeatedly every 15 minutes. The shots and the microseism noise were recorded at several seismic stations at the same time. That data set gives us the opportunity to compare the changes in seismic wave velocity recovered through <span class="hlt">cross</span> <span class="hlt">correlation</span> of ambient noise and changes we measure through active shots from the airgun. The aim is to distinguish between apparent seismic velocity changes and seismic velocity changes caused by changes in the medium. We also use the data set to track the direction of the microseism noise sources to see if changes which are only recovered through <span class="hlt">cross</span> <span class="hlt">correlation</span> can be related to temporal and spatial variations of the microseism noise sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S41B2723H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S41B2723H"><span>Verification of Green's <span class="hlt">Function</span> Approximation from Ambient Noise <span class="hlt">Cross-correlation</span> using Three-year Continuous Seismic Data in South Niigata Prefecture, Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hayashida, T.; Yoshimi, M.</p> <p>2015-12-01</p> <p>A continuous broadband-to-strong motion observation network that consists of 15 stations has been in operation since September 2011 in south Niigata Prefecture (Yoshimi et al., 2012). We applied seismic interferometry to the ambient noise data for the purpose of validating three-dimensional S-wave velocity structure (deep sedimentary structure) models beneath the observation area (Hayashida and Yoshimi, 2012, 2015). We used 37-month ambient noise data (October 2011 - October 2014) to obtain nine component (RR, TT, ZZ, RT, TR, ZR, ZT, RZ, and TZ) <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> between two stations (105 station pairs) for distances from 4.3 to 40.7 km, according to the signal processing technique by Bensen et al. (2007). Our results show that signal-to-noise ratios (SNRs) of <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> increase logarithmically as the stacking number increase and the wave trains are clear especially for TT and ZZ correlations. Some station pairs show large SNRs even for RT and TR correlations, indicating complicated velocity structure beneath the area. To extract Rayleigh-wave Green's <span class="hlt">functions</span> efficiently, we applied body and surface wave separation technique by Takagi et al. (2014). We obtained clear dispersion curves of Rayleigh and Love waves in the frequency range between 0.1 and 1.0 Hz that correspond well to theoretical curves from existing velocity structure model of Sekiguchi et al. (2009). We found that maximum detectable wavelength of surface wave is nearly equivalent to station-to-station distance for near station pairs (< 20 km), whereas the maximum wavelength is about a half of station-to-station distance for further station pairs. We also investigated the effectiveness of uniform noise source distribution assumptions by comparing hourly stacked complex coherence <span class="hlt">functions</span> of ambient noise between neighboring two stations and theoretical Bessel <span class="hlt">functions</span> of the of first kind of zero order with the existing crustal (Takeda et al., 2012) and deep sedimentary</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PEPI..234...46C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PEPI..234...46C"><span>Lithospheric VS models in the Campanian Plain (Italy) by integrating Rayleigh wave dispersion data from noise <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> and earthquake recordings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Costanzo, M. R.; Nunziata, C.</p> <p>2014-09-01</p> <p><span class="hlt">Cross-correlation</span> <span class="hlt">functions</span> of long noise recordings with two broadband stations and earthquake recordings in the Campanian Plain have been processed with frequency time analysis to extract the fundamental mode of Rayleigh waves. Group velocities have been combined with regional group and phase velocity data in the non-linear inversion, with Hedgehog method, in order to get average shear wave velocity models for lithospheric structures extending to 73 km of depth. The structural model below the central part of the Campanian Plain is characterized by a covering of pyroclastics and alluvial sediments, about 2 km thick, on the carbonate platform with VS ranging from 2.30-2.40 to 2.85-3.15 km/s. However, the presence of lava bodies within the carbonates cannot be excluded in the light of the same density and seismic velocities. At greater depths, a main feature is represented by a sharp increment of velocity around 8-9 km of depth (VS of 3.85 km/s), which can be attributed to the presence of metamorphic rocks, overlying a low VS layer (5% velocity reduction), at about 14-15 km of depth. Such structural model resembles those found below the quiescent Roccamonfina and Colli Albani volcanoes, and can be interpreted as the signature of a cooling magma chamber. Moreover, a low VS layer is detected at 8-9 km of depth towards the Apennines and at 6 km of depth in the southernmost part of the Campanian Plain, nearby Mt. Vesuvius. Such low velocity layer seems to be a regional feature since it has been found below Roccamonfina in the North, Campi Flegrei, bay of Napoli and Mt. Vesuvius in the South, and can be explained by the widespread presence of partially melted material below the whole Campanian area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SPIE.7533E..0HM','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SPIE.7533E..0HM"><span>Passive imaging with <span class="hlt">cross</span> <span class="hlt">correlations</span> in a discrete random medium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moscoso, M.; Papanicolaou, G.; Sun, R.-H.</p> <p>2010-01-01</p> <p>The purpose of this paper is to study the potential and limitations of <span class="hlt">cross-correlation</span> techniques using numerical simulations, and in particular, we intend to show (i) an estimate of the Green's <span class="hlt">function</span> in different configurations and (ii) results for passive imaging. This problem seems especially interesting in seismology, nondestructive testing, structure health monitoring, and wireless sensor networks. To compute <span class="hlt">cross</span> <span class="hlt">correlations</span> of the impulse signals collected by the receivers, we consider scattering by discrete scatterers to generate impluse responses with targets and without targets. We compute the difference of the <span class="hlt">cross</span> <span class="hlt">correlations</span> with targets and the <span class="hlt">cross</span> <span class="hlt">correlations</span> without targets to estimate the backpropagator (Green's <span class="hlt">function</span>) in the Kirchhoff migration <span class="hlt">functional</span>. The migration <span class="hlt">functional</span> is essential to compute images of targets. We run numerical simulations for different configurations to explore the limitations of this <span class="hlt">cross</span> <span class="hlt">correlation</span> methodology from the results of passive imaging.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21567661','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21567661"><span>THE SPATIAL CLUSTERING OF ROSAT ALL-SKY SURVEY AGNs. II. HALO OCCUPATION DISTRIBUTION MODELING OF THE <span class="hlt">CROSS-CORRELATION</span> <span class="hlt">FUNCTION</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Miyaji, Takamitsu; Aceves, Hector; Krumpe, Mirko; Coil, Alison L.</p> <p>2011-01-10</p> <p>This is the second paper of a series that reports on our investigation of the clustering properties of active galactic nuclei (AGNs) in the ROSAT All-Sky Survey (RASS) through <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> (CCFs) with Sloan Digital Sky Survey (SDSS) galaxies. In this paper, we apply the Halo Occupation Distribution (HOD) model to the CCFs between the RASS broad-line AGNs with SDSS luminous red galaxies (LRGs) in the redshift range 0.16 < z < 0.36 that was calculated in Paper I. In our HOD modeling approach, we use the known HOD of LRGs and constrain the HOD of the AGNs by a model fit to the CCF. For the first time, we are able to go beyond quoting merely a 'typical' AGN host halo mass, M{sub h}, and model the full distribution <span class="hlt">function</span> of AGN host dark matter halos. In addition, we are able to determine the large-scale bias and the mean M{sub h} more accurately. We explore the behavior of three simple HOD models. Our first model (Model A) is a truncated power-law HOD model in which all AGNs are satellites. With this model, we find an upper limit to the slope ({alpha}) of the AGN HOD that is far below unity. The other two models have a central component, which has a step <span class="hlt">function</span> form, where the HOD is constant above a minimum mass, without (Model B) or with (Model C) an upper mass cutoff, in addition to the truncated power-law satellite component, similar to the HOD that is found for galaxies. In these two models we find that the upper limits on {alpha} are still below unity, with {alpha} {approx}< 0.95 and {alpha} {approx}< 0.84 for Models B and C, respectively. Our analysis suggests that the satellite AGN occupation increases slower than, or may even decrease with, M{sub h}, in contrast to the satellite HODs of luminosity-threshold samples of galaxies, which, in contrast, grow approximately as (N{sub s}) {proportional_to} M{sup {alpha}}{sub h} with {alpha} {approx} 1. These results are consistent with observations that the AGN fraction in groups and clusters</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.S23D..06T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.S23D..06T"><span>Method of Second <span class="hlt">Cross-Correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tanimoto, T.; Alvizuri, C.</p> <p>2008-12-01</p> <p>In a high frequency band above 1 Hz, the Noise <span class="hlt">Cross-Correlation</span> method works because of multiple scattering but in a lower frequency band, say below 0.2 Hz, it works mainly because of wide distribution of sources as effects from multiple scattering are much smaller. As noise-source locations change seasonably, seasonal variations are often seen in the correlated seismograms (first correlogram). In Southern California, weaker signals are seen in summer because of weaker ocean waves. Source distribution also introduces another problem; near the coast, it is often found that the paths perpendicular to the coast show good signal in correlograms but the paths parallel to the coast do not necessarily contain good signals. This is directly related to the source locations, i.e., ocean waves in low frequency bands. This feature does harm in tomographic studies, especially for the recovery of azimuthal anisotropy, as measurements from all azimuths are the key to its success. One method to circumvent this problem is the method of Second <span class="hlt">Cross-Correlation</span>. This method computes <span class="hlt">cross-correlations</span> of Greens <span class="hlt">function</span> that have been obtained by the noise <span class="hlt">cross-correlation</span> method. We call it here as Second <span class="hlt">Cross-Correlation</span> and refer to correlated seismograms as second correlograms. Campillo et al. (2008) showed an application to coda in Greens <span class="hlt">functions</span> for the first time but in this study we focus on the entire waveforms. We present theoretical analysis of this method with some examples from Southern California. It works for a relatively dense array of network only, but such dense arrays are available in many parts of the world now. We extend our theoretical analysis in Tanimoto (2008) for first correlograms which was a full normal-mode- theory version of theories developed by Snieder (2004), Roux et al. (2005) and Wapenaar (2004). There are some distinct features in second correlograms; for example, while an ordinary (first) correlogram depends on f**2, where f is the source</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhyA..390.1677Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhyA..390.1677Z"><span>Study of <span class="hlt">cross-correlation</span> in a self-affine time series of taxi accidents</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zebende, G. F.; da Silva, P. A.; Machado Filho, A.</p> <p>2011-05-01</p> <p>We study in this paper the <span class="hlt">cross-correlation</span> between self-affine time series of real variables recorded simultaneously in cases of taxi accidents. For this purpose, we apply the DCCA method and show that the <span class="hlt">cross-correlation</span> can be divided into three distinct groups, if we look for the detrended covariance <span class="hlt">function</span>, i.e., long-range <span class="hlt">cross-correlations</span>, short-range <span class="hlt">cross-correlations</span> and no <span class="hlt">cross-correlations</span>. Finally, it will be seen that the detrended covariance <span class="hlt">function</span> is robust, if compared with other methods, in identifying these types of <span class="hlt">cross-correlations</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_3 --> <div id="page_4" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="61"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160011519','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160011519"><span><span class="hlt">Cross</span> <span class="hlt">Correlation</span> versus Normalized Mutual Information on Image Registration</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tan, Bin; Tilton, James C.; Lin, Guoqing</p> <p>2016-01-01</p> <p>This is the first study to quantitatively assess and compare <span class="hlt">cross</span> <span class="hlt">correlation</span> and normalized mutual information methods used to register images in subpixel scale. The study shows that the normalized mutual information method is less sensitive to unaligned edges due to the spectral response differences than is <span class="hlt">cross</span> <span class="hlt">correlation</span>. This characteristic makes the normalized image resolution a better candidate for band to band registration. Improved band-to-band registration in the data from satellite-borne instruments will result in improved <span class="hlt">retrievals</span> of key science measurements such as cloud properties, vegetation, snow and fire.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AMT.....8..751L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AMT.....8..751L"><span>Characterization and verification of ACAM slit <span class="hlt">functions</span> for trace-gas <span class="hlt">retrievals</span> during the 2011 DISCOVER-AQ flight campaign</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, C.; Liu, X.; Kowalewski, M. G.; Janz, S. J.; González Abad, G.; Pickering, K. E.; Chance, K.; Lamsal, L. N.</p> <p>2015-02-01</p> <p>The Airborne Compact Atmospheric Mapper (ACAM), an ultraviolet/visible/near-infrared spectrometer, has been flown on board the NASA UC-12 aircraft during the Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) campaigns to provide remote sensing observations of tropospheric and boundary-layer pollutants from its radiance measurements. To assure the trace-gas <span class="hlt">retrieval</span> from ACAM measurements we perform detailed characterization and verification of ACAM slit <span class="hlt">functions</span>. The wavelengths and slit <span class="hlt">functions</span> of ACAM measurements are characterized for the air-quality channel (~304-500 nm) through <span class="hlt">cross-correlation</span> with a high-resolution solar irradiance reference spectrum after necessarily accounting for atmospheric gas absorption and the ring effect in the calibration process. The derived slit <span class="hlt">functions</span>, assuming a hybrid combination of asymmetric Gaussian and top-hat slit <span class="hlt">functions</span>, agree very well with the laboratory-measured slit <span class="hlt">functions</span>. Comparisons of trace-gas <span class="hlt">retrievals</span> between using derived and measured slit <span class="hlt">functions</span> demonstrate that the <span class="hlt">cross-correlation</span> technique can be reliably used to characterize slit <span class="hlt">functions</span> for trace-gas <span class="hlt">retrievals</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5328397','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/5328397"><span>Recirculating <span class="hlt">cross-correlation</span> detector</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Andrews, W.H. Jr.; Roberts, M.J.</p> <p>1985-01-18</p> <p>A digital <span class="hlt">cross-correlation</span> detector is provided in which two time-varying signals are correlated by repetitively comparing data samples stored in digital form to detect correlation between the two signals. The signals are sampled at a selected rate converted to digital form, and stored in separate locations in separate memories. When the memories are filled, the data samples from each memory are first fed word-by-word through a multiplier and summing circuit and each result is compared to the last in a peak memory circuit and if larger than the last is retained in the peak memory. Then the address line to leading signal memory is offset by one byte to affect one sample period delay of a known amount in that memory and the data in the two memories are then multiplied word-by-word once again and summed. If a new result is larger than a former sum, it is saved in the peak memory together with the time delay. The recirculating process continues with the address of the one memory being offset one additional byte each cycle until the address is shifted through the length of the memory. The correlation between the two signals is indicated by the peak signal stored in the peak memory together with the delay time at which the peak occurred. The circuit is faster and considerably less expensive than comparable accuracy correlation detectors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27723507','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27723507"><span>Improving information <span class="hlt">retrieval</span> in <span class="hlt">functional</span> analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rodriguez, Juan C; González, Germán A; Fresno, Cristóbal; Llera, Andrea S; Fernández, Elmer A</p> <p>2016-12-01</p> <p>Transcriptome analysis is essential to understand the mechanisms regulating key biological processes and <span class="hlt">functions</span>. The first step usually consists of identifying candidate genes; to find out which pathways are affected by those genes, however, <span class="hlt">functional</span> analysis (FA) is mandatory. The most frequently used strategies for this purpose are Gene Set and Singular Enrichment Analysis (GSEA and SEA) over Gene Ontology. Several statistical methods have been developed and compared in terms of computational efficiency and/or statistical appropriateness. However, whether their results are similar or complementary, the sensitivity to parameter settings, or possible bias in the analyzed terms has not been addressed so far. Here, two GSEA and four SEA methods and their parameter combinations were evaluated in six datasets by comparing two breast cancer subtypes with well-known differences in genetic background and patient outcomes. We show that GSEA and SEA lead to different results depending on the chosen statistic, model and/or parameters. Both approaches provide complementary results from a biological perspective. Hence, an Integrative <span class="hlt">Functional</span> Analysis (IFA) tool is proposed to improve information <span class="hlt">retrieval</span> in FA. It provides a common gene expression analytic framework that grants a comprehensive and coherent analysis. Only a minimal user parameter setting is required, since the best SEA/GSEA alternatives are integrated. IFA utility was demonstrated by evaluating four prostate cancer and the TCGA breast cancer microarray datasets, which showed its biological generalization capabilities. Copyright © 2016 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JCAP...08..009M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JCAP...08..009M"><span>Modeling CMB lensing <span class="hlt">cross</span> <span class="hlt">correlations</span> with CLEFT</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Modi, Chirag; White, Martin; Vlah, Zvonimir</p> <p>2017-08-01</p> <p>A new generation of surveys will soon map large fractions of sky to ever greater depths and their science goals can be enhanced by exploiting <span class="hlt">cross</span> <span class="hlt">correlations</span> between them. In this paper we study <span class="hlt">cross</span> <span class="hlt">correlations</span> between the lensing of the CMB and biased tracers of large-scale structure at high z. We motivate the need for more sophisticated bias models for modeling increasingly biased tracers at these redshifts and propose the use of perturbation theories, specifically Convolution Lagrangian Effective Field Theory (CLEFT). Since such signals reside at large scales and redshifts, they can be well described by perturbative approaches. We compare our model with the current approach of using scale independent bias coupled with fitting <span class="hlt">functions</span> for non-linear matter power spectra, showing that the latter will not be sufficient for upcoming surveys. We illustrate our ideas by estimating σ8 from the auto- and cross-spectra of mock surveys, finding that CLEFT returns accurate and unbiased results at high z. We discuss uncertainties due to the redshift distribution of the tracers, and several avenues for future development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18685035','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18685035"><span><span class="hlt">Cross-correlation</span> in the auditory coincidence detectors of owls.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fischer, Brian J; Christianson, G Björn; Peña, José Luis</p> <p>2008-08-06</p> <p>Interaural time difference (ITD) plays a central role in many auditory <span class="hlt">functions</span>, most importantly in sound localization. The classic model for how ITD is computed was put forth by Jeffress (1948). One of the predictions of the Jeffress model is that the neurons that compute ITD should behave as <span class="hlt">cross-correlators</span>. Whereas <span class="hlt">cross-correlation</span>-like properties of the ITD-computing neurons have been reported, attempts to show that the shape of the ITD response <span class="hlt">function</span> is determined by the spectral tuning of the neuron, a core prediction of <span class="hlt">cross-correlation</span>, have been unsuccessful. Using reverse correlation analysis, we demonstrate in the barn owl that the relationship between the spectral tuning and the ITD response of the ITD-computing neurons is that predicted by <span class="hlt">cross-correlation</span>. Moreover, we show that a model of coincidence detector responses derived from responses to binaurally uncorrelated noise is consistent with binaural interaction based on <span class="hlt">cross-correlation</span>. These results are thus consistent with one of the key tenets of the Jeffress model. Our work sets forth both the methodology to answer whether <span class="hlt">cross-correlation</span> describes coincidence detector responses and a demonstration that in the barn owl, the result is that expected by theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2637928','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2637928"><span><span class="hlt">Cross-Correlation</span> in the Auditory Coincidence Detectors of Owls</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fischer, Brian J.; Christianson, G.Björn; Peña, José Luis</p> <p>2009-01-01</p> <p>Interaural time difference (ITD) plays a central role in many auditory <span class="hlt">functions</span>, most importantly in sound localization. The classic model for how ITD is computed was put forth by Jeffress (1948). One of the predictions of the Jeffress model is that the neurons that compute ITD should behave as <span class="hlt">cross-correlators</span>. Whereas <span class="hlt">cross-correlation</span>-like properties of the ITD-computing neurons have been reported, attempts to show that the shape of the ITD response <span class="hlt">function</span> is determined by the spectral tuning of the neuron, a core prediction of <span class="hlt">cross-correlation</span>, have been unsuccessful. Using reverse correlation analysis, we demonstrate in the barn owl that the relationship between the spectral tuning and the ITD response of the ITD-computing neurons is that predicted by <span class="hlt">cross-correlation</span>. Moreover, we show that a model of coincidence detector responses derived from responses to binaurally uncorrelated noise is consistent with binaural interaction based on <span class="hlt">cross-correlation</span>. These results are thus consistent with one of the key tenets of the Jeffress model. Our work sets forth both the methodology to answer whether <span class="hlt">cross-correlation</span> describes coincidence detector responses and a demonstration that in the barn owl, the result is that expected by theory. PMID:18685035</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22304166','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22304166"><span>Statistical tests for power-law <span class="hlt">cross-correlated</span> processes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Podobnik, Boris; Jiang, Zhi-Qiang; Zhou, Wei-Xing; Stanley, H Eugene</p> <p>2011-12-01</p> <p>For stationary time series, the cross-covariance and the <span class="hlt">cross-correlation</span> as <span class="hlt">functions</span> of time lag n serve to quantify the similarity of two time series. The latter measure is also used to assess whether the <span class="hlt">cross-correlations</span> are statistically significant. For nonstationary time series, the analogous measures are detrended <span class="hlt">cross-correlations</span> analysis (DCCA) and the recently proposed detrended <span class="hlt">cross-correlation</span> coefficient, ρ(DCCA)(T,n), where T is the total length of the time series and n the window size. For ρ(DCCA)(T,n), we numerically calculated the Cauchy inequality -1 ≤ ρ(DCCA)(T,n) ≤ 1. Here we derive -1 ≤ ρ DCCA)(T,n) ≤ 1 for a standard variance-covariance approach and for a detrending approach. For overlapping windows, we find the range of ρ(DCCA) within which the <span class="hlt">cross-correlations</span> become statistically significant. For overlapping windows we numerically determine-and for nonoverlapping windows we derive--that the standard deviation of ρ(DCCA)(T,n) tends with increasing T to 1/T. Using ρ(DCCA)(T,n) we show that the Chinese financial market's tendency to follow the U.S. market is extremely weak. We also propose an additional statistical test that can be used to quantify the existence of <span class="hlt">cross-correlations</span> between two power-law correlated time series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhRvE..84f6118P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhRvE..84f6118P"><span>Statistical tests for power-law <span class="hlt">cross-correlated</span> processes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Podobnik, Boris; Jiang, Zhi-Qiang; Zhou, Wei-Xing; Stanley, H. Eugene</p> <p>2011-12-01</p> <p>For stationary time series, the cross-covariance and the <span class="hlt">cross-correlation</span> as <span class="hlt">functions</span> of time lag n serve to quantify the similarity of two time series. The latter measure is also used to assess whether the <span class="hlt">cross-correlations</span> are statistically significant. For nonstationary time series, the analogous measures are detrended <span class="hlt">cross-correlations</span> analysis (DCCA) and the recently proposed detrended <span class="hlt">cross-correlation</span> coefficient, ρDCCA(T,n), where T is the total length of the time series and n the window size. For ρDCCA(T,n), we numerically calculated the Cauchy inequality -1≤ρDCCA(T,n)≤1. Here we derive -1≤ρDCCA(T,n)≤1 for a standard variance-covariance approach and for a detrending approach. For overlapping windows, we find the range of ρDCCA within which the <span class="hlt">cross-correlations</span> become statistically significant. For overlapping windows we numerically determine—and for nonoverlapping windows we derive—that the standard deviation of ρDCCA(T,n) tends with increasing T to 1/T. Using ρDCCA(T,n) we show that the Chinese financial market's tendency to follow the U.S. market is extremely weak. We also propose an additional statistical test that can be used to quantify the existence of <span class="hlt">cross-correlations</span> between two power-law correlated time series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S13B2576S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S13B2576S"><span>Pre-Processing Noise <span class="hlt">Cross-Correlations</span> with Equalizing the Network Covariance Matrix Eigen-Spectrum</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Seydoux, L.; de Rosny, J.; Shapiro, N.</p> <p>2016-12-01</p> <p>Theoretically, the extraction of Green <span class="hlt">functions</span> from noise <span class="hlt">cross-correlation</span> requires the ambient seismic wavefield to be generated by uncorrelated sources evenly distributed in the medium. Yet, this condition is often not verified. Strong events such as earthquakes often produce highly coherent transient signals. Also, the microseismic noise is generated at specific places on the Earth's surface with source regions often very localized in space. Different localized and persistent seismic sources may contaminate the <span class="hlt">cross-correlations</span> of continuous records resulting in spurious arrivals or asymmetry and, finally, in biased travel-time measurements. Pre-processing techniques therefore must be applied to the seismic data in order to reduce the effect of noise anisotropy and the influence of strong localized events. Here we describe a pre-processing approach that uses the covariance matrix computed from signals recorded by a network of seismographs. We extend the widely used time and spectral equalization pre-processing to the equalization of the covariance matrix spectrum (i.e., its ordered eigenvalues). This approach can be considered as a spatial equalization. This method allows us to correct for the wavefield anisotropy in two ways: (1) the influence of strong directive sources is substantially attenuated, and (2) the weakly excited modes are reinforced, allowing to partially recover the conditions required for the Green's <span class="hlt">function</span> <span class="hlt">retrieval</span>. We also present an eigenvector-based spatial filter used to distinguish between surface and body waves. This last filter is used together with the equalization of the eigenvalue spectrum. We simulate two-dimensional wavefield in a heterogeneous medium with strongly dominating source. We show that our method greatly improves the travel-time measurements obtained from the inter-station <span class="hlt">cross-correlation</span> <span class="hlt">functions</span>. Also, we apply the developed method to the USArray data and pre-process the continuous records strongly influenced</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28057726','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28057726"><span>Reduced Hippocampal <span class="hlt">Functional</span> Connectivity During Episodic Memory <span class="hlt">Retrieval</span> in Autism.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cooper, Rose A; Richter, Franziska R; Bays, Paul M; Plaisted-Grant, Kate C; Baron-Cohen, Simon; Simons, Jon S</p> <p>2017-02-01</p> <p>Increasing recent research has sought to understand the recollection impairments experienced by individuals with autism spectrum disorder (ASD). Here, we tested whether these memory deficits reflect a reduction in the probability of <span class="hlt">retrieval</span> success or in the precision of memory representations. We also used <span class="hlt">functional</span> magnetic resonance imaging (fMRI) to study the neural mechanisms underlying memory encoding and <span class="hlt">retrieval</span> in ASD, focusing particularly on the <span class="hlt">functional</span> connectivity of core episodic memory networks. Adults with ASD and typical control participants completed a memory task that involved studying visual displays and subsequently using a continuous dial to recreate their appearance. The ASD group exhibited reduced <span class="hlt">retrieval</span> success, but there was no evidence of a difference in <span class="hlt">retrieval</span> precision. fMRI data revealed similar patterns of brain activity and <span class="hlt">functional</span> connectivity during memory encoding in the 2 groups, though encoding-related lateral frontal activity predicted subsequent <span class="hlt">retrieval</span> success only in the control group. During memory <span class="hlt">retrieval</span>, the ASD group exhibited attenuated lateral frontal activity and substantially reduced hippocampal connectivity, particularly between hippocampus and regions of the fronto-parietal control network. These findings demonstrate notable differences in brain <span class="hlt">function</span> during episodic memory <span class="hlt">retrieval</span> in ASD and highlight the importance of <span class="hlt">functional</span> connectivity to understanding recollection-related <span class="hlt">retrieval</span> deficits in this population.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5390398','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5390398"><span>Reduced Hippocampal <span class="hlt">Functional</span> Connectivity During Episodic Memory <span class="hlt">Retrieval</span> in Autism</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cooper, Rose A.; Richter, Franziska R.; Bays, Paul M.; Plaisted-Grant, Kate C.; Baron-Cohen, Simon</p> <p>2017-01-01</p> <p>Abstract Increasing recent research has sought to understand the recollection impairments experienced by individuals with autism spectrum disorder (ASD). Here, we tested whether these memory deficits reflect a reduction in the probability of <span class="hlt">retrieval</span> success or in the precision of memory representations. We also used <span class="hlt">functional</span> magnetic resonance imaging (fMRI) to study the neural mechanisms underlying memory encoding and <span class="hlt">retrieval</span> in ASD, focusing particularly on the <span class="hlt">functional</span> connectivity of core episodic memory networks. Adults with ASD and typical control participants completed a memory task that involved studying visual displays and subsequently using a continuous dial to recreate their appearance. The ASD group exhibited reduced <span class="hlt">retrieval</span> success, but there was no evidence of a difference in <span class="hlt">retrieval</span> precision. fMRI data revealed similar patterns of brain activity and <span class="hlt">functional</span> connectivity during memory encoding in the 2 groups, though encoding-related lateral frontal activity predicted subsequent <span class="hlt">retrieval</span> success only in the control group. During memory <span class="hlt">retrieval</span>, the ASD group exhibited attenuated lateral frontal activity and substantially reduced hippocampal connectivity, particularly between hippocampus and regions of the fronto-parietal control network. These findings demonstrate notable differences in brain <span class="hlt">function</span> during episodic memory <span class="hlt">retrieval</span> in ASD and highlight the importance of <span class="hlt">functional</span> connectivity to understanding recollection-related <span class="hlt">retrieval</span> deficits in this population. PMID:28057726</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2715865','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2715865"><span>Evaluation of the Performance of Information Theory-Based Methods and <span class="hlt">Cross-Correlation</span> to Estimate the <span class="hlt">Functional</span> Connectivity in Cortical Networks</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Garofalo, Matteo; Nieus, Thierry; Massobrio, Paolo; Martinoia, Sergio</p> <p>2009-01-01</p> <p><span class="hlt">Functional</span> connectivity of in vitro neuronal networks was estimated by applying different statistical algorithms on data collected by Micro-Electrode Arrays (MEAs). First we tested these “connectivity methods” on neuronal network models at an increasing level of complexity and evaluated the performance in terms of ROC (Receiver Operating Characteristic) and PPC (Positive Precision Curve), a new defined complementary method specifically developed for <span class="hlt">functional</span> links identification. Then, the algorithms better estimated the actual connectivity of the network models, were used to extract <span class="hlt">functional</span> connectivity from cultured cortical networks coupled to MEAs. Among the proposed approaches, Transfer Entropy and Joint-Entropy showed the best results suggesting those methods as good candidates to extract <span class="hlt">functional</span> links in actual neuronal networks from multi-site recordings. PMID:19652720</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22126846','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22126846"><span><span class="hlt">CROSS-CORRELATIONS</span> AS A COSMOLOGICAL CARBON MONOXIDE DETECTOR</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pullen, Anthony R.; Dore, Olivier; Chang, Tzu-Ching; Lidz, Adam</p> <p>2013-05-01</p> <p>We present a new procedure to measure the large-scale carbon monoxide (CO) emissions across cosmic history. As a tracer of large-scale structure (LSS), the CO gas content as a <span class="hlt">function</span> of redshift can be quantified by its three-dimensional fluctuation power spectra. Furthermore, <span class="hlt">cross-correlating</span> CO emission with other LSS tracers offers a way to measure the emission as a <span class="hlt">function</span> of scale and redshift. Here we introduce the model relevant for such a <span class="hlt">cross-correlation</span> measurement between CO and other LSS tracers, and between different CO rotational lines. We propose a novel use of cosmic microwave background (CMB) data and attempt to extract redshifted CO emissions embedded in the Wilkinson Microwave Anisotropy Probe (WMAP) data set. We <span class="hlt">cross-correlate</span> the all-sky WMAP7 data with LSS data sets, namely, the photometric quasar sample and the luminous red galaxy sample from the Sloan Digital Sky Survey Data Releases 6 and 7, respectively. We are unable to detect a <span class="hlt">cross-correlation</span> signal with either CO(1-0) or CO(2-1) lines, mainly due to the instrumental noise in the WMAP data. However, we are able to rule out models more than three times greater than our more optimistic model. We discuss the <span class="hlt">cross-correlation</span> signal from the thermal Sunyaev-Zeldovich effect and dust as potential contaminants, and quantify their impact for our CO measurements. We discuss forecasts for current CMB experiments and a hypothetical future CO-focused experiment, and propose to <span class="hlt">cross-correlate</span> CO temperature data with the Hobby-Eberly Telescope Dark Energy Experiment Ly{alpha}-emitter sample, for which a signal-to-noise ratio of 58 is possible.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22858972','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22858972"><span>Optical anemometry based on the temporal <span class="hlt">cross-correlation</span> of angle-of-arrival fluctuations obtained from spatially separated light sources.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tichkule, Shiril; Muschinski, Andreas</p> <p>2012-07-20</p> <p>The temporal <span class="hlt">cross-correlation</span> <span class="hlt">function</span> of the angle-of-arrival (AOA) fluctuations of two optical waves propagating through atmospheric turbulence carries information regarding the average wind velocity transverse to the propagation path. We present and discuss two estimators for the <span class="hlt">retrieval</span> of the path-averaged beam-transverse horizontal wind velocity, v(t). Both methods <span class="hlt">retrieve</span> v(t) from the temporal <span class="hlt">cross-correlation</span> <span class="hlt">function</span> of AOA fluctuations obtained from two closely spaced light-emitting diodes (LEDs). The first method relies on the time delay of the peak (TDP) of the <span class="hlt">cross-correlation</span> <span class="hlt">function</span>, and the second method exploits its slope at zero lag (SZL). Over a 9 h period during which v(t) varied between -1.3 ms(-1) and 2.0 ms(-1), the maximum rms difference between optically <span class="hlt">retrieved</span> and in situ measured 10 s estimates of v(t) was found to be 0.18 ms(-1) for the TDP estimator and 0.23 ms(-1) for the SZL estimator. Applicability and limitations of these two optical wind <span class="hlt">retrieval</span> techniques are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6854881','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6854881"><span>Intensity <span class="hlt">cross-correlation</span> in stimulated Raman scattering</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Raymer, M.G.; Westling, L.A.</p> <p>1986-01-01</p> <p>The intensity <span class="hlt">cross-correlation</span> <span class="hlt">function</span> between a broad-band pump laser and generated Stokes light has been measured by frequency mixing. A strong correlation has been found, whose magnitude varies with the collisional relaxation time of the Raman medium. 2 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..APRS15002B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..APRS15002B"><span><span class="hlt">Cross-Correlating</span> DES and SPT</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baxter, Eric</p> <p>2017-01-01</p> <p>The Dark Energy Survey (DES) and the South Pole Telescope (SPT) provide a uniquely powerful combination of overlapping optical imaging and cosmic microwave background (CMB) data. <span class="hlt">Cross-correlations</span> between DES and SPT are expected to arise from several physical effects, including gravitational lensing, the Sunyaev-Zel'dovich (SZ) effect, and the Integrated Sachs-Wolfe effect. The resultant correlations contain information not accessible to either experiment on its own. Measurement of these correlations offers several exciting possibilities, such as improved cosmological parameter constraints, improved understanding of systematics affecting the two experiments, and calibration of the masses of galaxy clusters at high redshift. In this talk I will summarize recent results obtained by <span class="hlt">cross-correlating</span> early DES data with data from the SPT-SZ survey and will discuss prospects for future <span class="hlt">cross-correlation</span> measurements with these two surveys.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=controlled+AND+vocabulary+AND+indexing+AND+retrieval&pg=2&id=EJ457843','ERIC'); return false;" href="https://eric.ed.gov/?q=controlled+AND+vocabulary+AND+indexing+AND+retrieval&pg=2&id=EJ457843"><span>Belief <span class="hlt">Function</span> Model for Information <span class="hlt">Retrieval</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Silva, Wagner Teixeira da; Milidiu, Ruy Luiz</p> <p>1993-01-01</p> <p>Describes the Belief <span class="hlt">Function</span> Model for automatic indexing and ranking of documents which is based on a controlled vocabulary and on term frequencies in each document. Belief <span class="hlt">Function</span> Theory is explained, and the Belief <span class="hlt">Function</span> Model is compared to the Standard Vector Space Model. (17 references) (LRW)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1166014','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1166014"><span>Background-free balanced optical <span class="hlt">cross</span> <span class="hlt">correlator</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Nejadmalayeri, Amir Hossein; Kaertner, Franz X</p> <p>2014-12-23</p> <p>A balanced optical <span class="hlt">cross</span> <span class="hlt">correlator</span> includes an optical waveguide, a first photodiode including a first n-type semiconductor and a first p-type semiconductor positioned about the optical waveguide on a first side of the optical waveguide's point of symmetry, and a second photodiode including a second n-type semiconductor and a second p-type semiconductor positioned about the optical waveguide on a second side of the optical waveguide's point of symmetry. A balanced receiver including first and second inputs is configured to produce an output current or voltage that reflects a difference in currents or voltages, originating from the first and the second photodiodes of the balanced <span class="hlt">cross</span> <span class="hlt">correlator</span> and fed to the first input and to the second input of the balanced receiver.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Chaos..27f3111W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Chaos..27f3111W"><span>Multifractal temporally weighted detrended <span class="hlt">cross-correlation</span> analysis to quantify power-law <span class="hlt">cross-correlation</span> and its application to stock markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wei, Yun-Lan; Yu, Zu-Guo; Zou, Hai-Long; Anh, Vo</p> <p>2017-06-01</p> <p>A new method—multifractal temporally weighted detrended <span class="hlt">cross-correlation</span> analysis (MF-TWXDFA)—is proposed to investigate multifractal <span class="hlt">cross-correlations</span> in this paper. This new method is based on multifractal temporally weighted detrended fluctuation analysis and multifractal <span class="hlt">cross-correlation</span> analysis (MFCCA). An innovation of the method is applying geographically weighted regression to estimate local trends in the nonstationary time series. We also take into consideration the sign of the fluctuations in computing the corresponding detrended cross-covariance <span class="hlt">function</span>. To test the performance of the MF-TWXDFA algorithm, we apply it and the MFCCA method on simulated and actual series. Numerical tests on artificially simulated series demonstrate that our method can accurately detect long-range <span class="hlt">cross-correlations</span> for two simultaneously recorded series. To further show the utility of MF-TWXDFA, we apply it on time series from stock markets and find that power-law <span class="hlt">cross-correlation</span> between stock returns is significantly multifractal. A new coefficient, MF-TWXDFA <span class="hlt">cross-correlation</span> coefficient, is also defined to quantify the levels of <span class="hlt">cross-correlation</span> between two time series.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28679233','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28679233"><span>Multifractal temporally weighted detrended <span class="hlt">cross-correlation</span> analysis to quantify power-law <span class="hlt">cross-correlation</span> and its application to stock markets.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wei, Yun-Lan; Yu, Zu-Guo; Zou, Hai-Long; Anh, Vo</p> <p>2017-06-01</p> <p>A new method-multifractal temporally weighted detrended <span class="hlt">cross-correlation</span> analysis (MF-TWXDFA)-is proposed to investigate multifractal <span class="hlt">cross-correlations</span> in this paper. This new method is based on multifractal temporally weighted detrended fluctuation analysis and multifractal <span class="hlt">cross-correlation</span> analysis (MFCCA). An innovation of the method is applying geographically weighted regression to estimate local trends in the nonstationary time series. We also take into consideration the sign of the fluctuations in computing the corresponding detrended cross-covariance <span class="hlt">function</span>. To test the performance of the MF-TWXDFA algorithm, we apply it and the MFCCA method on simulated and actual series. Numerical tests on artificially simulated series demonstrate that our method can accurately detect long-range <span class="hlt">cross-correlations</span> for two simultaneously recorded series. To further show the utility of MF-TWXDFA, we apply it on time series from stock markets and find that power-law <span class="hlt">cross-correlation</span> between stock returns is significantly multifractal. A new coefficient, MF-TWXDFA <span class="hlt">cross-correlation</span> coefficient, is also defined to quantify the levels of <span class="hlt">cross-correlation</span> between two time series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25868704','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25868704"><span>Bootstrap testing for <span class="hlt">cross-correlation</span> under low firing activity.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>González-Montoro, Aldana M; Cao, Ricardo; Espinosa, Nelson; Cudeiro, Javier; Mariño, Jorge</p> <p>2015-06-01</p> <p>A new <span class="hlt">cross-correlation</span> synchrony index for neural activity is proposed. The index is based on the integration of the kernel estimation of the <span class="hlt">cross-correlation</span> <span class="hlt">function</span>. It is used to test for the dynamic synchronization levels of spontaneous neural activity under two induced brain states: sleep-like and awake-like. Two bootstrap resampling plans are proposed to approximate the distribution of the test statistics. The results of the first bootstrap method indicate that it is useful to discern significant differences in the synchronization dynamics of brain states characterized by a neural activity with low firing rate. The second bootstrap method is useful to unveil subtle differences in the synchronization levels of the awake-like state, depending on the activation pathway.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhRvE..73c6129R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhRvE..73c6129R"><span>Modeling <span class="hlt">cross</span> <span class="hlt">correlations</span> within a many-assets market</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Roman, H. E.; Albergante, M.; Colombo, M.; Croccolo, F.; Marini, F.; Riccardi, C.</p> <p>2006-03-01</p> <p>A simple model for simulating <span class="hlt">cross</span> <span class="hlt">correlations</span> of a many-assets market is discussed. Correlations between assets are initially considered within the context of the well-known one-factor model, in which a driving term common to all stocks is present. The results are compared to those of real market data corresponding to a set of 445 stocks taken from the Standard and Poors 500 index. The model is further extended by introducing a stochastic volatility within each time series using an autoregressive scheme. This artifical market reproduces the empirically observed fat tails in the distribution <span class="hlt">function</span> of logarithmic price variations and, more important, leads to additional <span class="hlt">cross</span> <span class="hlt">correlations</span> between the time series, in better agreement with the real market behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20018772','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20018772"><span><span class="hlt">Cross-correlations</span> between volume change and price change.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Podobnik, Boris; Horvatic, Davor; Petersen, Alexander M; Stanley, H Eugene</p> <p>2009-12-29</p> <p>In finance, one usually deals not with prices but with growth rates R, defined as the difference in logarithm between two consecutive prices. Here we consider not the trading volume, but rather the volume growth rate R, the difference in logarithm between two consecutive values of trading volume. To this end, we use several methods to analyze the properties of volume changes |R|, and their relationship to price changes |R|. We analyze 14,981 daily recordings of the Standard and Poor's (S & P) 500 Index over the 59-year period 1950-2009, and find power-law <span class="hlt">cross-correlations</span> between |R| and |R| by using detrended <span class="hlt">cross-correlation</span> analysis (DCCA). We introduce a joint stochastic process that models these <span class="hlt">cross-correlations</span>. Motivated by the relationship between |R| and |R|, we estimate the tail exponent alpha of the probability density <span class="hlt">function</span> P(|R|) approximately |R|(-1-alpha) for both the S & P 500 Index as well as the collection of 1819 constituents of the New York Stock Exchange Composite Index on 17 July 2009. As a new method to estimate alpha, we calculate the time intervals tau(q) between events where R > q. We demonstrate that tau(q), the average of tau(q), obeys tau(q) approximately q(alpha). We find alpha approximately 3. Furthermore, by aggregating all tau(q) values of 28 global financial indices, we also observe an approximate inverse cubic law.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1239272-precise-relative-earthquake-magnitudes-from-cross-correlation','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1239272-precise-relative-earthquake-magnitudes-from-cross-correlation"><span>Precise Relative Earthquake Magnitudes from <span class="hlt">Cross</span> <span class="hlt">Correlation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Cleveland, K. Michael; Ammon, Charles J.</p> <p>2015-04-21</p> <p>We present a method to estimate precise relative magnitudes using <span class="hlt">cross</span> <span class="hlt">correlation</span> of seismic waveforms. Our method incorporates the intercorrelation of all events in a group of earthquakes, as opposed to individual event pairings relative to a reference event. This method works well when a reliable reference event does not exist. We illustrate the method using vertical strike-slip earthquakes located in the northeast Pacific and Panama fracture zone regions. Our results are generally consistent with the Global Centroid Moment Tensor catalog, which we use to establish a baseline for the relative event sizes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1239272','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1239272"><span>Precise Relative Earthquake Magnitudes from <span class="hlt">Cross</span> <span class="hlt">Correlation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cleveland, K. Michael; Ammon, Charles J.</p> <p>2015-04-21</p> <p>We present a method to estimate precise relative magnitudes using <span class="hlt">cross</span> <span class="hlt">correlation</span> of seismic waveforms. Our method incorporates the intercorrelation of all events in a group of earthquakes, as opposed to individual event pairings relative to a reference event. This method works well when a reliable reference event does not exist. We illustrate the method using vertical strike-slip earthquakes located in the northeast Pacific and Panama fracture zone regions. Our results are generally consistent with the Global Centroid Moment Tensor catalog, which we use to establish a baseline for the relative event sizes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SPIE.7858E..09D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SPIE.7858E..09D"><span>Phase <span class="hlt">function</span> effects for ocean color <span class="hlt">retrieval</span> algorithm</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Du, KePing; Lee, Zhongping</p> <p>2010-10-01</p> <p>Inherent optical properties (IOPs), e.g., absorption, back scattering coefficients, and volume scattering <span class="hlt">function</span>, are important parameters for radiance transfer simulation. Commercially available instruments (e.g., Wetlabs ACS, BB9, etc, and HOBILabs a-sphere, HS6, etc) basically only measure absorption and back scattering coefficients. In this paper, we used the same IOPs of International Ocean-Colour Coordinating Group (IOCCG) report 5 and Hydrolight to simulate the radiance distribution, however, different phase <span class="hlt">functions</span>, say, a new phase <span class="hlt">function</span> derived from the measured data by multispectral volume scattering meter (MVSM) in coastal waters, the widely used Petzold average phase <span class="hlt">function</span>, and the Fournier-Forand (FF) phase <span class="hlt">function</span>, were employed in the simulations. The simulation results were used to develop the <span class="hlt">retrieval</span> algorithm with angular effects correction based on the quasi-analytical algorithm(QAA) developed by Lee et al.. Results showed that not only the back scattering probability, but also the angular shape of phase <span class="hlt">function</span> are important for ocean color <span class="hlt">retrieval</span> algorithm. Considering the importance of phase <span class="hlt">function</span> in ocean color remote sensing, methods to validate the phase <span class="hlt">function</span> data should be developed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1335007','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1335007"><span>Exploiting <span class="hlt">Cross</span> <span class="hlt">Correlations</span> and Joint Analyses</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rhodes, J.; Allen, S.; Benson, B. A.; Chang, T.; de Putter, R.; Dodelson, S.; Doré, O.; Honscheid, K.; Linder, E.; Ménard, B.; Newman, J.; Nord, B.; Rozo, E.; Rykoff, E.; Vallinotto, A.; Weinberg, D.</p> <p>2014-02-28</p> <p>In this report, we present a wide variety of ways in which information from multiple probes of dark energy may be combined to obtain additional information not accessible when they are considered separately. Fundamentally, because all major probes are affected by the underlying distribution of matter in the regions studied, there exist covariances between them that can provide information on cosmology. Combining multiple probes allows for more accurate (less contaminated by systematics) and more precise (since there is cosmological information encoded in <span class="hlt">cross-correlation</span> statistics) measurements of dark energy. The potential of <span class="hlt">cross-correlation</span> methods is only beginning to be realized. By bringing in information from other wavelengths, the capabilities of the existing probes of dark energy can be enhanced and systematic effects can be mitigated further. We present a mixture of work in progress and suggestions for future scientific efforts. Given the scope of future dark energy experiments, the greatest gains may only be realized with more coordination and cooperation between multiple project teams; we recommend that this interchange should begin sooner, rather than later, to maximize scientific gains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ASPC..475..135F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ASPC..475..135F"><span>HEALPix Based <span class="hlt">Cross-Correlation</span> in Astronomy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fernique, P.; Durand, D.; Boch, T.; Oberto, A.; Pineau, F.</p> <p>2013-10-01</p> <p>We are presenting our work on a <span class="hlt">cross</span> <span class="hlt">correlation</span> system based on HEALPix cells indexing. The system allows users to answer scientific questions like “please find all HST images on which there is an observation of a radio quiet quasar” in a single query. The baseline of this system is the creation of the HEALPix indexes grouped hierarchically and organized in a special format file called MOC (see <a href='http://ivoa.net/Documents/Notes/MOC'>http://ivoa.net/Documents/Notes/MOC</a>) developed by the CDS. Using the MOC files, the <span class="hlt">cross</span> <span class="hlt">correlation</span> between images and or catalogues is reduced to searches only in meaningful areas. Under the condition that the survey database also internally uses a HEALPix positional index, the search result comes back almost immediately (typically a few seconds). We have started building the index for some surveys, catalogues (VizieR catalogues, Simbad, etc.) and some pointed mode archives (like HST at CADC) and are developing an elementary library to support basic operations on any input MOC files. The usage of the MOC files is starting to be used throughout the VO community as a general indexing method and tools such as Aladin and TOPCAT are starting to make use of them.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017FNL....1650004X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017FNL....1650004X"><span>Analyzing the <span class="hlt">Cross-Correlation</span> Between Onshore and Offshore RMB Exchange Rates Based on Multifractal Detrended <span class="hlt">Cross-Correlation</span> Analysis (MF-DCCA)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xie, Chi; Zhou, Yingying; Wang, Gangjin; Yan, Xinguo</p> <p></p> <p>We use the multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA) method to explore the multifractal behavior of the <span class="hlt">cross-correlation</span> between exchange rates of onshore RMB (CNY) and offshore RMB (CNH) against US dollar (USD). The empirical data are daily prices of CNY/USD and CNH/USD from May 1, 2012 to February 29, 2016. The results demonstrate that: (i) the <span class="hlt">cross-correlation</span> between CNY/USD and CNH/USD is persistent and its fluctuation is smaller when the order of fluctuation <span class="hlt">function</span> is negative than that when the order is positive; (ii) the multifractal behavior of the <span class="hlt">cross-correlation</span> between CNY/USD and CNH/USD is significant during the sample period; (iii) the dynamic Hurst exponents obtained by the rolling windows analysis show that the <span class="hlt">cross-correlation</span> is stable when the global economic situation is good and volatile in bad situation; and (iv) the non-normal distribution of original data has a greater effect on the multifractality of the <span class="hlt">cross-correlation</span> between CNY/USD and CNH/USD than the temporary correlation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4438072','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4438072"><span>A New Methodology of Spatial <span class="hlt">Cross-Correlation</span> Analysis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chen, Yanguang</p> <p>2015-01-01</p> <p>Spatial correlation modeling comprises both spatial autocorrelation and spatial <span class="hlt">cross-correlation</span> processes. The spatial autocorrelation theory has been well-developed. It is necessary to advance the method of spatial <span class="hlt">cross-correlation</span> analysis to supplement the autocorrelation analysis. This paper presents a set of models and analytical procedures for spatial <span class="hlt">cross-correlation</span> analysis. By analogy with Moran’s index newly expressed in a spatial quadratic form, a theoretical framework is derived for geographical <span class="hlt">cross-correlation</span> modeling. First, two sets of spatial <span class="hlt">cross-correlation</span> coefficients are defined, including a global spatial <span class="hlt">cross-correlation</span> coefficient and local spatial <span class="hlt">cross-correlation</span> coefficients. Second, a pair of scatterplots of spatial <span class="hlt">cross-correlation</span> is proposed, and the plots can be used to visually reveal the causality behind spatial systems. Based on the global <span class="hlt">cross-correlation</span> coefficient, Pearson’s correlation coefficient can be decomposed into two parts: direct correlation (partial correlation) and indirect correlation (spatial <span class="hlt">cross-correlation</span>). As an example, the methodology is applied to the relationships between China’s urbanization and economic development to illustrate how to model spatial <span class="hlt">cross-correlation</span> phenomena. This study is an introduction to developing the theory of spatial <span class="hlt">cross-correlation</span>, and future geographical spatial analysis might benefit from these models and indexes. PMID:25993120</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25993120','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25993120"><span>A new methodology of spatial <span class="hlt">cross-correlation</span> analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Yanguang</p> <p>2015-01-01</p> <p>Spatial correlation modeling comprises both spatial autocorrelation and spatial <span class="hlt">cross-correlation</span> processes. The spatial autocorrelation theory has been well-developed. It is necessary to advance the method of spatial <span class="hlt">cross-correlation</span> analysis to supplement the autocorrelation analysis. This paper presents a set of models and analytical procedures for spatial <span class="hlt">cross-correlation</span> analysis. By analogy with Moran's index newly expressed in a spatial quadratic form, a theoretical framework is derived for geographical <span class="hlt">cross-correlation</span> modeling. First, two sets of spatial <span class="hlt">cross-correlation</span> coefficients are defined, including a global spatial <span class="hlt">cross-correlation</span> coefficient and local spatial <span class="hlt">cross-correlation</span> coefficients. Second, a pair of scatterplots of spatial <span class="hlt">cross-correlation</span> is proposed, and the plots can be used to visually reveal the causality behind spatial systems. Based on the global <span class="hlt">cross-correlation</span> coefficient, Pearson's correlation coefficient can be decomposed into two parts: direct correlation (partial correlation) and indirect correlation (spatial <span class="hlt">cross-correlation</span>). As an example, the methodology is applied to the relationships between China's urbanization and economic development to illustrate how to model spatial <span class="hlt">cross-correlation</span> phenomena. This study is an introduction to developing the theory of spatial <span class="hlt">cross-correlation</span>, and future geographical spatial analysis might benefit from these models and indexes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PThPS.194..181M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PThPS.194..181M"><span>Temporal and <span class="hlt">Cross</span> <span class="hlt">Correlations</span> in Business News</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mizuno, T.; Takei, K.; Ohnishi, T.; Watanabe, T.</p> <p></p> <p>We empirically investigate temporal and <span class="hlt">cross</span> <span class="hlt">correlations</span> inthe frequency of news reports on companies, using a dataset of more than 100 million news articles reported in English by around 500 press agencies worldwide for the period 2003--2009. Our first finding is that the frequency of news reports on a company does not follow a Poisson process, but instead exhibits long memory with a positive autocorrelation for longer than one year. The second finding is that there exist significant correlations in the frequency of news across companies. Specifically, on a daily time scale or longer the frequency of news is governed by external dynamics, while on a time scale of minutes it is governed by internal dynamics. These two findings indicate that the frequency of news reports on companies has statistical properties similar to trading volume or price volatility in stock markets, suggesting that the flow of information through company news plays an important role in price dynamics in stock markets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S43C..03E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S43C..03E"><span>Investigating hum sources using <span class="hlt">cross-correlation</span> asymmetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ermert, L. A.; Fichtner, A.; Schimmel, M.</p> <p>2014-12-01</p> <p>The sources and excitation of the Earth's hum are current subjects of debate. Here, we propose an alternative approach to map power spectral density of hum sources. We are currently processing IRIS continuous seismic data spanning the last 10 years to obtain a <span class="hlt">cross-correlation</span> dataset. The amplitude-independent phase <span class="hlt">cross-correlation</span> provides correlation stacks that converge relatively rapidly and without the application of additional preprocessing such as spectral whitening. We calculate monthly stacks of approx. daily broadband geometrically normalized 'classic' and phase <span class="hlt">cross-correlations</span>. These can be recombined into 'seasonal' stacks of several months. Also, they can be restacked by month over several years, so as to investigate long-term average behavior during different months. Although these correlation <span class="hlt">functions</span> retain no absolute amplitude information, observational evidence from our data shows that the relative amplitudes of the causal and acausal branch differ between certain station pairs, indicating a preferential direction of wave propagation. We intend to use this directional characteristic to investigate source distribution of continuous seismic motions. In a first step, we project the measurements of amplitude asymmetry back along the station-station path using very simplified sensitivity kernels. These kernels can be obtained numerically or by using analytical 2-D Green's <span class="hlt">functions</span> for homogeneous media. We expect to obtain global maps of source regions for different seasons. In a further step (not to be presented here), the observations will be inverted for the geographical distribution of source power spectral density. We target hum as first example application, while the method could also be applied to other types of continuous seismic motion. The goal of our study is to obtain a global hum source map, which might benefit our understanding of the excitation mechanisms of hum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhyA..428...80W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhyA..428...80W"><span><span class="hlt">Cross-correlation</span> between interest rates and commodity prices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Qing; Hu, Yiming</p> <p>2015-06-01</p> <p>In this paper, we investigate <span class="hlt">cross-correlations</span> between interest rate and agricultural commodity markets. Based on a statistic of Podobnik et al. (2009), we find that the <span class="hlt">cross-correlations</span> are all significant. Using the MF-DFA and MF-DXA methods, we find strong multifractality in both auto-correlations and <span class="hlt">cross-correlations</span>. Moreover, the <span class="hlt">cross-correlations</span> are persistent. Finally, based on the technique of rolling window, the time-variation property of <span class="hlt">cross-correlations</span> is also revealed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhyA..392.5985E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhyA..392.5985E"><span>Multifractal detrended <span class="hlt">cross-correlation</span> analysis in the MENA area</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>El Alaoui, Marwane; Benbachir, Saâd</p> <p>2013-12-01</p> <p>In this paper, we investigated multifractal <span class="hlt">cross-correlations</span> qualitatively and quantitatively using a <span class="hlt">cross-correlation</span> test and the Multifractal detrended <span class="hlt">cross-correlation</span> analysis method (MF-DCCA) for markets in the MENA area. We used <span class="hlt">cross-correlation</span> coefficients to measure the level of this correlation. The analysis concerns four stock market indices of Morocco, Tunisia, Egypt and Jordan. The countries chosen are signatory of the Agadir agreement concerning the establishment of a free trade area comprising Arab Mediterranean countries. We computed the bivariate generalized Hurst exponent, Rényi exponent and spectrum of singularity for each pair of indices to measure quantitatively the <span class="hlt">cross-correlations</span>. By analyzing the results, we found the existence of multifractal <span class="hlt">cross-correlations</span> between all of these markets. We compared the spectrum width of these indices; we also found which pair of indices has a strong multifractal <span class="hlt">cross-correlation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016FrES...10..117N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016FrES...10..117N"><span>Long-range <span class="hlt">cross-correlation</span> between urban impervious surfaces and land surface temperatures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nie, Qin; Xu, Jianhua; Man, Wang</p> <p>2016-03-01</p> <p>The thermal effect of urban impervious surfaces (UIS) is a complex problem. It is thus necessary to study the relationship between UIS and land surface temperatures (LST) using complexity science theory and methods. This paper investigates the long-range <span class="hlt">cross-correlation</span> between UIS and LST with detrended <span class="hlt">cross-correlation</span> analysis and multifractal detrended <span class="hlt">cross-correlation</span> analysis, utilizing data from downtown Shanghai, China. UIS estimates were obtained from linear spectral mixture analysis, and LST was <span class="hlt">retrieved</span> through application of the mono-window algorithm, using Landsat Thematic Mapper and Enhanced Thematic Mapper Plus data for 1997-2010. These results highlight a positive long-range <span class="hlt">cross-correlation</span> between UIS and LST across People's Square in Shanghai. LST has a long memory for a certain spatial range of UIS values, such that a large increment in UIS is likely to be followed by a large increment in LST. While the multifractal long-range <span class="hlt">cross-correlation</span> between UIS and LST was observed over a longer time period in the W-E direction (2002-2010) than in the N-S (2007-2010), these observed correlations show a weakening during the study period as urbanization increased.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2799689','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2799689"><span><span class="hlt">Cross-correlations</span> between volume change and price change</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Podobnik, Boris; Horvatic, Davor; Petersen, Alexander M.; Stanley, H. Eugene</p> <p>2009-01-01</p> <p>In finance, one usually deals not with prices but with growth rates R, defined as the difference in logarithm between two consecutive prices. Here we consider not the trading volume, but rather the volume growth rate R̃, the difference in logarithm between two consecutive values of trading volume. To this end, we use several methods to analyze the properties of volume changes |R̃|, and their relationship to price changes |R|. We analyze 14,981 daily recordings of the Standard and Poor's (S & P) 500 Index over the 59-year period 1950–2009, and find power-law <span class="hlt">cross-correlations</span> between |R| and |R̃| by using detrended <span class="hlt">cross-correlation</span> analysis (DCCA). We introduce a joint stochastic process that models these <span class="hlt">cross-correlations</span>. Motivated by the relationship between |R| and |R̃|, we estimate the tail exponent α̃ of the probability density <span class="hlt">function</span> P(|R̃|) ∼ |R̃|−1−α̃ for both the S & P 500 Index as well as the collection of 1819 constituents of the New York Stock Exchange Composite Index on 17 July 2009. As a new method to estimate α̃, we calculate the time intervals τq between events where R̃ > q. We demonstrate that τ̃q, the average of τq, obeys τ̃q ∼ qα̃. We find α̃ ≈ 3. Furthermore, by aggregating all τq values of 28 global financial indices, we also observe an approximate inverse cubic law. PMID:20018772</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E2250N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E2250N"><span><span class="hlt">Cross-Correlations</span> in Quasar Radio Emission</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nefedyev, Yuri; Panischev, Oleg; Demin, Sergey</p> <p></p> <p>The main factors forming the complex evolution of the accretive astrophysical systems are nonlinearity, intermittency, nonstationarity and also collective phenomena. To discover the dynamic processes in these objects and to detain understanding their properties we need to use all the applicable analyzing methods. Here we use the Flicker-Noise Spectroscopy (FNS) as a phenomenological approach to analyzing and parameterizing the auto- and <span class="hlt">cross-correlations</span> in time series of astrophysical objects dynamics. As an example we consider the quasar flux radio spectral density at frequencies 2.7 GHz and 8.1 GHz. Data have been observed by Dr. N. Tanizuka (Laboratory for Complex Systems Analysis, Osaka Prefecture University) in a period of 1979 to 1988 (3 309 days). According to mental habits quasar is a very energetic and distant active galactic nucleus containing a supermassive black hole by size 10-10,000 times the Schwarzschild radius. The quasar is powered by an accretion disc around the black hole. The accretion disc material layers, moving around the black hole, are under the influence of gravitational and frictional forces. It results in raising the high temperature and arising the resonant and collective phenomena reflected in quasar emission dynamics. Radio emission dynamics of the quasar 0215p015 is characterized by three quasi-periodic processes, which are prevalent in considering dynamics. By contrast the 1641p399's emission dynamics have not any distinguish processes. It means the presence of high intermittency in accretive modes. The second difference moment allows comparing the degree of manifesting of resonant and chaotic components in initial time series of the quasar radio emission. The comparative analysis shows the dominating of chaotic part of 1641p399's dynamics whereas the radio emission of 0215p015 has the predominance of resonant component. Analyzing the collective features of the quasar radio emission intensity demonstrates the significant</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007EPJB...58..499D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007EPJB...58..499D"><span>World currency exchange rate <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Droå¼dż, S.; Górski, A. Z.; Kwapień, J.</p> <p>2007-08-01</p> <p>World currency network constitutes one of the most complex structures that is associated with the contemporary civilization. On a way towards quantifying its characteristics we study the <span class="hlt">cross</span> <span class="hlt">correlations</span> in changes of the daily foreign exchange rates within the basket of 60 currencies in the period December 1998 May 2005. Such a dynamics turns out to predominantly involve one outstanding eigenvalue of the correlation matrix. The magnitude of this eigenvalue depends however crucially on which currency is used as a base currency for the remaining ones. Most prominent it looks from the perspective of a peripheral currency. This largest eigenvalue is seen to systematically decrease and thus the structure of correlations becomes more heterogeneous, when more significant currencies are used as reference. An extreme case in this later respect is the USD in the period considered. Besides providing further insight into subtle nature of complexity, these observations point to a formal procedure that in general can be used for practical purposes of measuring the relative currencies significance on various time horizons.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhyA..391.2860G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhyA..391.2860G"><span>1/f behavior in <span class="hlt">cross-correlations</span> between absolute returns in a US market</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gvozdanovic, Igor; Podobnik, Boris; Wang, Duan; Eugene Stanley, H.</p> <p>2012-05-01</p> <p>Employing detrended fluctuation analysis (DFA) and detrended <span class="hlt">cross-correlations</span> analysis (DCCA), we analyze auto-correlations in the absolute returns for each of 30 Dow Jones Industrial Average (DJIA) constituents, Si, and <span class="hlt">cross-correlations</span> in the absolute returns between the DJIA and each Si. We find that each DJIA member follows the DJIA in absolute returns, since the DCCA curve for each pair (Si,DJIAi) exhibits strong <span class="hlt">cross-correlations</span>, with average DCCA exponent <λ>=1.03±0.04. This value for <λ> implies that the power-law <span class="hlt">cross-correlations</span> are of the 1/f <span class="hlt">functional</span> form. For the financial firms comprising the DJIA, we also find that the DFA and DCCA exponents controlling the duration of firm risk are somewhat larger than the corresponding values for the rest of the US financial industry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..395..293L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..395..293L"><span><span class="hlt">Cross-correlations</span> between crude oil and agricultural commodity markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Li</p> <p>2014-02-01</p> <p>In this paper, we investigate <span class="hlt">cross-correlations</span> between crude oil and agricultural commodity markets. Based on a popular statistical test proposed by Podobnik et al. (2009), we find that the linear return <span class="hlt">cross-correlations</span> are significant at larger lag lengths and the volatility <span class="hlt">cross-correlations</span> are highly significant at all of the lag lengths under consideration. Using a detrended <span class="hlt">cross-correlation</span> analysis (DCCA), we find that the return <span class="hlt">cross-correlations</span> are persistent for corn and soybean and anti-persistent for oat and soybean. The volatility <span class="hlt">cross-correlations</span> are strongly persistent. Using a nonlinear <span class="hlt">cross-correlation</span> measure, our results show that <span class="hlt">cross-correlations</span> are relatively weak but they are significant for smaller time scales. For larger time scales, the <span class="hlt">cross-correlations</span> are not significant. The reason may be that information transmission from crude oil market to agriculture markets can complete within a certain period of time. Finally, based on multifractal extension of DCCA, we find that the <span class="hlt">cross-correlations</span> are multifractal and high oil prices partly contribute to food crisis during the period of 2006-mid-2008.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014Fract..2250007Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014Fract..2250007Y"><span>Multiscale Detrended <span class="hlt">Cross-Correlation</span> Analysis of STOCK Markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yin, Yi; Shang, Pengjian</p> <p>2014-06-01</p> <p>In this paper, we employ the detrended <span class="hlt">cross-correlation</span> analysis (DCCA) to investigate the <span class="hlt">cross-correlations</span> between different stock markets. We report the results of <span class="hlt">cross-correlated</span> behaviors in US, Chinese and European stock markets in period 1997-2012 by using DCCA method. The DCCA shows the <span class="hlt">cross-correlated</span> behaviors of intra-regional and inter-regional stock markets in the short and long term which display the similarities and differences of <span class="hlt">cross-correlated</span> behaviors simply and roughly and the persistence of <span class="hlt">cross-correlated</span> behaviors of fluctuations. Then, because of the limitation and inapplicability of DCCA method, we propose multiscale detrended <span class="hlt">cross-correlation</span> analysis (MSDCCA) method to avoid "a priori" selecting the ranges of scales over which two coefficients of the classical DCCA method are identified, and employ MSDCCA to reanalyze these <span class="hlt">cross-correlations</span> to exhibit some important details such as the existence and position of minimum, maximum and bimodal distribution which are lost if the scale structure is described by two coefficients only and essential differences and similarities in the scale structures of <span class="hlt">cross-correlation</span> of intra-regional and inter-regional markets. More statistical characteristics of <span class="hlt">cross-correlation</span> obtained by MSDCCA method help us to understand how two different stock markets influence each other and to analyze the influence from thus two inter-regional markets on the <span class="hlt">cross-correlation</span> in detail, thus we get a richer and more detailed knowledge of the complex evolutions of dynamics of the <span class="hlt">cross-correlations</span> between stock markets. The application of MSDCCA is important to promote our understanding of the internal mechanisms and structures of financial markets and helps to forecast the stock indices based on our current results demonstrated the <span class="hlt">cross-correlations</span> between stock indices. We also discuss the MSDCCA methods of secant rolling window with different sizes and, lastly, provide some relevant implications and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4661444','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4661444"><span>Formaldehyde scavengers <span class="hlt">function</span> as novel antigen <span class="hlt">retrieval</span> agents</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Vollert, Craig T.; Moree, Wilna J.; Gregory, Steven; Bark, Steven J.; Eriksen, Jason L.</p> <p>2015-01-01</p> <p>Antigen <span class="hlt">retrieval</span> agents improve the detection of formaldehyde-fixed proteins, but how they work is not well understood. We demonstrate that formaldehyde scavenging represents a key characteristic associated with effective antigen <span class="hlt">retrieval</span>; under controlled temperature and pH conditions, scavenging improves the typical antigen <span class="hlt">retrieval</span> process through reversal of formaldehyde-protein adduct formation. This approach provides a rational framework for the identification and development of more effective antigen <span class="hlt">retrieval</span> agents. PMID:26612041</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27250630','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27250630"><span>Robust Statistical Detection of Power-Law <span class="hlt">Cross-Correlation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Blythe, Duncan A J; Nikulin, Vadim V; Müller, Klaus-Robert</p> <p>2016-06-02</p> <p>We show that widely used approaches in statistical physics incorrectly indicate the existence of power-law <span class="hlt">cross-correlations</span> between financial stock market fluctuations measured over several years and the neuronal activity of the human brain lasting for only a few minutes. While such <span class="hlt">cross-correlations</span> are nonsensical, no current methodology allows them to be reliably discarded, leaving researchers at greater risk when the spurious nature of <span class="hlt">cross-correlations</span> is not clear from the unrelated origin of the time series and rather requires careful statistical estimation. Here we propose a theory and method (PLCC-test) which allows us to rigorously and robustly test for power-law <span class="hlt">cross-correlations</span>, correctly detecting genuine and discarding spurious <span class="hlt">cross-correlations</span>, thus establishing meaningful relationships between processes in complex physical systems. Our method reveals for the first time the presence of power-law <span class="hlt">cross-correlations</span> between amplitudes of the alpha and beta frequency ranges of the human electroencephalogram.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...627089B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...627089B"><span>Robust Statistical Detection of Power-Law <span class="hlt">Cross-Correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blythe, Duncan A. J.; Nikulin, Vadim V.; Müller, Klaus-Robert</p> <p>2016-06-01</p> <p>We show that widely used approaches in statistical physics incorrectly indicate the existence of power-law <span class="hlt">cross-correlations</span> between financial stock market fluctuations measured over several years and the neuronal activity of the human brain lasting for only a few minutes. While such <span class="hlt">cross-correlations</span> are nonsensical, no current methodology allows them to be reliably discarded, leaving researchers at greater risk when the spurious nature of <span class="hlt">cross-correlations</span> is not clear from the unrelated origin of the time series and rather requires careful statistical estimation. Here we propose a theory and method (PLCC-test) which allows us to rigorously and robustly test for power-law <span class="hlt">cross-correlations</span>, correctly detecting genuine and discarding spurious <span class="hlt">cross-correlations</span>, thus establishing meaningful relationships between processes in complex physical systems. Our method reveals for the first time the presence of power-law <span class="hlt">cross-correlations</span> between amplitudes of the alpha and beta frequency ranges of the human electroencephalogram.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvE..96c2137H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvE..96c2137H"><span>Coda reconstruction from <span class="hlt">cross-correlation</span> of a diffuse field on thin elastic plates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hejazi Nooghabi, Aida; Boschi, Lapo; Roux, Philippe; de Rosny, Julien</p> <p>2017-09-01</p> <p>This study contributes to the evaluation of the robustness and accuracy of Green's <span class="hlt">function</span> reconstruction from <span class="hlt">cross-correlation</span> of strongly dispersed reverberated signals, with disentangling of the respective roles of ballistic and reverberated ("coda") contributions. We conduct a suite of experiments on a highly reverberating thin duralumin plate, where an approximately diffuse flexural wave field is generated by taking advantage of the plate reverberation and wave dispersion. A large number of impulsive sources that cover the whole surface of the plate are used to validate ambient-noise theory through comparison of the causal and anticausal (i.e., positive- and negative-time) terms of the <span class="hlt">cross-correlation</span> to one another and to the directly measured Green's <span class="hlt">function</span>. To quantify the contribution of the ballistic and coda signals, the <span class="hlt">cross-correlation</span> integral is defined over different time windows of variable length, and the accuracy of the reconstructed Green's <span class="hlt">function</span> is studied as a <span class="hlt">function</span> of the initial and end times of the integral. We show that even <span class="hlt">cross-correlations</span> measured over limited time windows converge to a significant part of the Green's <span class="hlt">function</span>. Convergence is achieved over a wide time window, which includes not only direct flexural-wave arrivals, but also the multiply reverberated coda. We propose a model, based on normal-mode analysis, that relates the similarity between the <span class="hlt">cross-correlation</span> and the Green's <span class="hlt">function</span> to the statistical properties of the plate. We also determine quantitatively how incoherent noise degrades the estimation of the Green's <span class="hlt">function</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MsT..........5C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MsT..........5C"><span>Comparisons of seismic interferometry by <span class="hlt">cross</span> <span class="hlt">correlation</span>, deconvolution, and cross coherence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chojnacki, John T.</p> <p></p> <p>Ambient noise seismic interferometry (ANSI) has been applied widely for geophysical investigations including earthquake tomography, civil engineering and seismic exploration purposes. Comparing this approach with the traditional active seismic survey, the application of ANSI is cost effective, environmentally friendly and easily repeatable. Conventional seismic interferometry by <span class="hlt">cross</span> <span class="hlt">correlating</span> wavefields recorded at different receivers has already obtained fruitful results. Even though the application of seismic interferometry (SI) by <span class="hlt">cross</span> <span class="hlt">correlation</span> has been successful, different methods for the processing workflow such as cross coherence and deconvolution have been conducted in an effort to improve the resolution. While these three methods have been evaluated for shear wave imaging of the near surface using surface waves by other authors, no conclusive study has been performed to compare the results from these methods for reflection surveys. In this study, by considering three common methods of <span class="hlt">retrieving</span> a virtual seismic record, I compare the methods and analyze the results with respect to their signal-to-noise ratios. I applied ANSI to numerically modeled data to <span class="hlt">retrieve</span> reflection responses for both base and repeat surveys monitoring the time-lapse changes of the impedance at the top of a reservoir before and after CO2 injection. The <span class="hlt">retrieved</span> seismic response by the three methods including <span class="hlt">cross</span> <span class="hlt">correlation</span>, deconvolution and cross coherence are also compared for the field noise data recorded near the CO2 storage site in Ketzin, Germany. While all three provide adequate results in noise-free synthetic data examples, the cross coherence method yielded improved images using real data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhyA..429...17F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhyA..429...17F"><span>Multifractal <span class="hlt">cross-correlation</span> analysis in electricity spot market</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fan, Qingju; Li, Dan</p> <p>2015-07-01</p> <p>In this paper, we investigate the multiscale <span class="hlt">cross-correlations</span> between electricity price and trading volume in Czech market based on a newly developed algorithm, called Multifractal <span class="hlt">Cross-Correlation</span> Analysis (MFCCA). The new algorithm is a natural multifractal generalization of the Detrended <span class="hlt">Cross-Correlation</span> Analysis (DCCA), and is sensitive to <span class="hlt">cross-correlation</span> structure and free from limitations of other algorithms. By considering the original sign of the cross-covariance, it allows us to properly quantify and detect the subtle characteristics of two simultaneous recorded time series. First, the multifractality and the long range anti-persistent auto-correlations of price return and trading volume variation are confirmed using Multifractal Detrended Fluctuation Analysis (MF-DFA). Furthermore, we show that there exist long-range anti-persistent <span class="hlt">cross-correlations</span> between price return and trading volume variation by MFCCA. And we also identify that the <span class="hlt">cross-correlations</span> disappear on the level of relative small fluctuations. In order to obtain deeper insight into the dynamics of the electricity market, we analyze the relation between generalized Hurst exponent and the multifractal <span class="hlt">cross-correlation</span> scaling exponent λq. We find that the difference between the generalized Hurst exponent and the multifractal <span class="hlt">cross-correlation</span> scaling exponent is significantly different for smaller fluctuation, which indicates that the multifractal character of <span class="hlt">cross-correlations</span> resembles more each other for electricity price and trading volume on the level of large fluctuations and weakens for the smaller ones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21361436','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21361436"><span>Acoustic ship signature measurements by <span class="hlt">cross-correlation</span> method.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fillinger, Laurent; Sutin, Alexander; Sedunov, Alexander</p> <p>2011-02-01</p> <p><span class="hlt">Cross-correlation</span> methods were applied for the estimation of the power spectral density and modulation spectrum of underwater noise generated by moving vessels. The <span class="hlt">cross-correlation</span> of the signal from two hydrophones allows the separation of vessel acoustic signatures in a busy estuary. Experimental data recorded in the Hudson River are used for demonstration that <span class="hlt">cross-correlation</span> method measured the same ship noise and ship noise modulation spectra as conventional methods. The <span class="hlt">cross-correlation</span> method was then applied for the separation of the acoustic signatures of two ships present simultaneously. Presented methods can be useful for ship traffic monitoring and small ship classification, even in noisy harbor environments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3862264','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3862264"><span><span class="hlt">Functional</span> Heterogeneity in Posterior Parietal Cortex Across Attention and Episodic Memory <span class="hlt">Retrieval</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hutchinson, J. Benjamin; Uncapher, Melina R.; Weiner, Kevin S.; Bressler, David W.; Silver, Michael A.; Preston, Alison R.; Wagner, Anthony D.</p> <p>2014-01-01</p> <p>While attention is critical for event memory, debate has arisen regarding the extent to which posterior parietal cortex (PPC) activation during episodic <span class="hlt">retrieval</span> reflects engagement of PPC-mediated mechanisms of attention. Here, we directly examined the relationship between attention and memory, within and across subjects, using <span class="hlt">functional</span> magnetic resonance imaging attention-mapping and episodic <span class="hlt">retrieval</span> paradigms. During <span class="hlt">retrieval</span>, 4 <span class="hlt">functionally</span> dissociable PPC regions were identified. Specifically, 2 PPC regions positively tracked <span class="hlt">retrieval</span> outcomes: lateral intraparietal sulcus (latIPS) indexed graded item memory strength, whereas angular gyrus (AnG) tracked recollection. By contrast, 2 other PPC regions demonstrated nonmonotonic relationships with <span class="hlt">retrieval</span>: superior parietal lobule (SPL) tracked <span class="hlt">retrieval</span> reaction time, consistent with a graded engagement of top-down attention, whereas temporoparietal junction displayed a complex pattern of below-baseline <span class="hlt">retrieval</span> activity, perhaps reflecting disengagement of bottom-up attention. Analyses of <span class="hlt">retrieval</span> effects in PPC topographic spatial attention maps (IPS0-IPS5; SPL1) revealed that IPS5 and SPL1 exhibited a nonmonotonic relationship with <span class="hlt">retrieval</span> outcomes resembling that in the SPL region, further suggesting that SPL activation during <span class="hlt">retrieval</span> reflects top-down attention. While demands on PPC attention mechanisms vary during <span class="hlt">retrieval</span> attempts, the present <span class="hlt">functional</span> parcellation of PPC indicates that 2 additional mechanisms (mediated by latIPS and AnG) positively track <span class="hlt">retrieval</span> outcomes. PMID:23019246</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23019246','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23019246"><span><span class="hlt">Functional</span> heterogeneity in posterior parietal cortex across attention and episodic memory <span class="hlt">retrieval</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hutchinson, J Benjamin; Uncapher, Melina R; Weiner, Kevin S; Bressler, David W; Silver, Michael A; Preston, Alison R; Wagner, Anthony D</p> <p>2014-01-01</p> <p>While attention is critical for event memory, debate has arisen regarding the extent to which posterior parietal cortex (PPC) activation during episodic <span class="hlt">retrieval</span> reflects engagement of PPC-mediated mechanisms of attention. Here, we directly examined the relationship between attention and memory, within and across subjects, using <span class="hlt">functional</span> magnetic resonance imaging attention-mapping and episodic <span class="hlt">retrieval</span> paradigms. During <span class="hlt">retrieval</span>, 4 <span class="hlt">functionally</span> dissociable PPC regions were identified. Specifically, 2 PPC regions positively tracked <span class="hlt">retrieval</span> outcomes: lateral intraparietal sulcus (latIPS) indexed graded item memory strength, whereas angular gyrus (AnG) tracked recollection. By contrast, 2 other PPC regions demonstrated nonmonotonic relationships with <span class="hlt">retrieval</span>: superior parietal lobule (SPL) tracked <span class="hlt">retrieval</span> reaction time, consistent with a graded engagement of top-down attention, whereas temporoparietal junction displayed a complex pattern of below-baseline <span class="hlt">retrieval</span> activity, perhaps reflecting disengagement of bottom-up attention. Analyses of <span class="hlt">retrieval</span> effects in PPC topographic spatial attention maps (IPS0-IPS5; SPL1) revealed that IPS5 and SPL1 exhibited a nonmonotonic relationship with <span class="hlt">retrieval</span> outcomes resembling that in the SPL region, further suggesting that SPL activation during <span class="hlt">retrieval</span> reflects top-down attention. While demands on PPC attention mechanisms vary during <span class="hlt">retrieval</span> attempts, the present <span class="hlt">functional</span> parcellation of PPC indicates that 2 additional mechanisms (mediated by latIPS and AnG) positively track <span class="hlt">retrieval</span> outcomes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16740314','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16740314"><span>Estimation of short-time <span class="hlt">cross-correlation</span> between frequency bands of event related EEG.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zygierewicz, J; Mazurkiewicz, J; Durka, P J; Franaszczuk, P J; Crone, N E</p> <p>2006-10-30</p> <p>Simultaneous variations of the event-related power changes (ERD/ERS) are often observed in a number of frequency bands. ERD/ERS measures are usually based on the relative changes of power in a given single frequency band. Within such an approach one cannot answer questions concerning the mutual relations between the band-power variations observed in different frequency bands. This paper addresses the problem of estimating and assessing the significance of the average <span class="hlt">cross-correlation</span> between ERD/ERS phenomena occurring in two frequency bands. The <span class="hlt">cross-correlation</span> <span class="hlt">function</span> in a natural way also provides estimation of the delay between ERD/ERS in those bands. The proposed method is based on estimating the short-time <span class="hlt">cross-correlation</span> <span class="hlt">function</span> between relative changes of power in two selected frequency bands. The <span class="hlt">cross-correlation</span> <span class="hlt">function</span> is estimated in each trial separately and then averaged across trials. The significance of those mean <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> is evaluated by means of a nonparametric test. The basic properties of the method are presented on simulated signals, and an example application to real EEG and ECoG signals is given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950061839&hterms=up+date&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dup%2Bdate','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950061839&hterms=up+date&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dup%2Bdate"><span>Bringing the <span class="hlt">cross-correlation</span> method up to date</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Statler, Thomas</p> <p>1995-01-01</p> <p>The <span class="hlt">cross-correlation</span> (XC) method of Tonry & Davis (1979, AJ, 84, 1511) is generalized to arbitrary parametrized line profiles. In the new algorithm the correlation <span class="hlt">function</span> itself, rather than the observed galaxy spectrum, is fitted by the model line profile: this removes much of the complication in the error analysis caused by template mismatch. Like the Fourier correlation quotient (FCQ) method of Bender (1990, A&A, 229, 441), the inferred line profiles are, up to a normalization constant, independent of template mismatch as long as there are no blended lines. The standard reduced chi(exp 2) is a good measure of the fit of the inferred velocity distribution, largely decoupled from the fit of the spectral template. The updated XC method performs as well as other recently developed methods, with the added virtue of conceptual simplicity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S41A4415R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S41A4415R"><span><span class="hlt">Cross-correlations</span> of ambient noise recorded by accelerometers.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rábade García, S. E.; Ramirez-Guzman, L.</p> <p>2014-12-01</p> <p>We investigate the ambient noise <span class="hlt">cross-correlations</span> obtained by using properly corrected accelerometric recordings, and determine velocity structure in central Mexico based on a dispersion analysis. The data used comprise ten months of continuous recordings - from April 2013 to January 2014 - of ambient seismic noise at stations operated by the National Seismological Service of Mexico and the Engineering Strong Ground Motion Network of the National Autonomous University of Mexico (UNAM). The vertical component of ambient noise was base-line corrected, filtered, and properly integrated before extracting Green's <span class="hlt">functions</span> (GF), which were compared successfully against GF obtained using recordings from broadband velocity sensors. In order to obtain dispersion curves, we estimated group and phase velocities applying the FTAN analysis technique and obtained s-wave velocity profiles at selected regions. We conclude and highlight that the use of widely deployed accelerographs to conduct regional studies using ambient noise tomography is feasible</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995AJ....109.1371S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995AJ....109.1371S"><span>Bringing the <span class="hlt">cross-correlation</span> method up to date</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Statler, Thomas</p> <p>1995-03-01</p> <p>The <span class="hlt">cross-correlation</span> (XC) method of Tonry & Davis (1979, AJ, 84, 1511) is generalized to arbitrary parametrized line profiles. In the new algorithm the correlation <span class="hlt">function</span> itself, rather than the observed galaxy spectrum, is fitted by the model line profile: this removes much of the complication in the error analysis caused by template mismatch. Like the Fourier correlation quotient (FCQ) method of Bender (1990, A&A, 229, 441), the inferred line profiles are, up to a normalization constant, independent of template mismatch as long as there are no blended lines. The standard reduced chi2 is a good measure of the fit of the inferred velocity distribution, largely decoupled from the fit of the spectral template. The updated XC method performs as well as other recently developed methods, with the added virtue of conceptual simplicity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060037936&hterms=beer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dbeer','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060037936&hterms=beer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dbeer"><span>(abstract) Cross with Your Spectra? <span class="hlt">Cross-Correlate</span> Instead!</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Beer, Reinhard</p> <p>1994-01-01</p> <p>The use of <span class="hlt">cross-correlation</span> for certain types of spectral analysis is discussed. Under certain circumstances, the use of <span class="hlt">cross-correlation</span> between a real spectrum and either a model or another spectrum can provide a very powerful tool for spectral analysis. The method (and its limitations) will be described with concrete examples using ATMOS data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1414N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1414N"><span>Non-Stationary Effects and <span class="hlt">Cross</span> <span class="hlt">Correlations</span> in Solar Activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nefedyev, Yuri; Panischev, Oleg; Demin, Sergey</p> <p>2016-07-01</p> <p>In this paper within the framework of the Flicker-Noise Spectroscopy (FNS) we consider the dynamic properties of the solar activity by analyzing the Zurich sunspot numbers. As is well-known astrophysics objects are the non-stationary open systems, whose evolution are the quite individual and have the alternation effects. The main difference of FNS compared to other related methods is the separation of the original signal reflecting the dynamics of solar activity into three frequency bands: system-specific "resonances" and their interferential contributions at lower frequencies, chaotic "random walk" ("irregularity-jump") components at larger frequencies, and chaotic "irregularity-spike" (inertial) components in the highest frequency range. Specific parameters corresponding to each of the bands are introduced and calculated. These irregularities as well as specific resonance frequencies are considered as the information carriers on every hierarchical level of the evolution of a complex natural system with intermittent behavior, consecutive alternation of rapid chaotic changes in the values of dynamic variables on small time intervals with small variations of the values on longer time intervals ("laminar" phases). The jump and spike irregularities are described by power spectra and difference moments (transient structural <span class="hlt">functions</span>) of the second order. FNS allows revealing the most crucial points of the solar activity dynamics by means of "spikiness" factor. It is shown that this variable behaves as the predictor of crucial changes of the sunspot number dynamics, particularly when the number comes up to maximum value. The change of averaging interval allows revealing the non-stationary effects depending by 11-year cycle and by inside processes in a cycle. To consider the <span class="hlt">cross</span> <span class="hlt">correlations</span> between the different variables of solar activity we use the Zurich sunspot numbers and the sequence of corona's radiation energy. The FNS-approach allows extracting the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170004336','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170004336"><span>Signal Digitizer and <span class="hlt">Cross-Correlation</span> Application Specific Integrated Circuit</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Baranauskas, Dalius (Inventor); Baranauskas, Gytis (Inventor); Zelenin, Denis (Inventor); Kangaslahti, Pekka (Inventor); Tanner, Alan B. (Inventor); Lim, Boon H. (Inventor)</p> <p>2017-01-01</p> <p>According to one embodiment, a <span class="hlt">cross-correlator</span> comprises a plurality of analog front ends (AFEs), a <span class="hlt">cross-correlation</span> circuit and a data serializer. Each of the AFEs comprises a variable gain amplifier (VGA) and a corresponding analog-to-digital converter (ADC) in which the VGA receives and modifies a unique analog signal associates with a measured analog radio frequency (RF) signal and the ADC produces digital data associated with the modified analog signal. Communicatively coupled to the AFEs, the <span class="hlt">cross-correlation</span> circuit performs a <span class="hlt">cross-correlation</span> operation on the digital data produced from different measured analog RF signals. The data serializer is communicatively coupled to the summing and <span class="hlt">cross-correlating</span> matrix and continuously outputs a prescribed amount of the correlated digital data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.S53D..01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.S53D..01M"><span>Time reversal imaging and <span class="hlt">cross-correlations</span> techniques by normal mode theory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Montagner, J.; Fink, M.; Capdeville, Y.; Phung, H.; Larmat, C.</p> <p>2007-12-01</p> <p>Time-reversal methods were successfully applied in the past to acoustic waves in many fields such as medical imaging, underwater acoustics, non destructive testing and recently to seismic waves in seismology for earthquake imaging. The increasing power of computers and numerical methods (such as spectral element methods) enables one to simulate more and more accurately the propagation of seismic waves in heterogeneous media and to develop new applications, in particular time reversal in the three-dimensional Earth. Generalizing the scalar approach of Draeger and Fink (1999), the theoretical understanding of time-reversal method can be addressed for the 3D- elastic Earth by using normal mode theory. It is shown how to relate time- reversal methods on one hand, with auto-correlation of seismograms for source imaging and on the other hand, with <span class="hlt">cross-correlation</span> between receivers for structural imaging and <span class="hlt">retrieving</span> Green <span class="hlt">function</span>. The loss of information will be discussed. In the case of source imaging, automatic location in time and space of earthquakes and unknown sources is obtained by time reversal technique. In the case of big earthquakes such as the Sumatra-Andaman earthquake of december 2004, we were able to reconstruct the spatio-temporal history of the rupture. We present here some new applications at the global scale of these techniques on synthetic tests and on real data.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24929372','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24929372"><span>Temporal <span class="hlt">cross-correlation</span> asymmetry and departure from equilibrium in a bistable chemical system.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bianca, C; Lemarchand, A</p> <p>2014-06-14</p> <p>This paper aims at determining sustained reaction fluxes in a nonlinear chemical system driven in a nonequilibrium steady state. The method relies on the computation of <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> for the internal fluctuations of chemical species concentrations. By employing Langevin-type equations, we derive approximate analytical formulas for the <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> associated with nonlinear dynamics. Kinetic Monte Carlo simulations of the chemical master equation are performed in order to check the validity of the Langevin equations for a bistable chemical system. The two approaches are found in excellent agreement, except for critical parameter values where the bifurcation between monostability and bistability occurs. From the theoretical point of view, the results imply that the behavior of <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> cannot be exploited to measure sustained reaction fluxes in a specific nonlinear system without the prior knowledge of the associated chemical mechanism and the rate constants.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003ApOpt..42.1564H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003ApOpt..42.1564H"><span>Irradiance Inversion Theory to <span class="hlt">Retrieve</span> Volume Scattering <span class="hlt">Function</span> of Seawater</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hirata, Takafumi</p> <p>2003-03-01</p> <p>An attempt to <span class="hlt">retrieve</span> the volume scattering <span class="hlt">function</span> (VSF) of source-free and no-inelastic-scattering ocean water is made from the upwelling irradiance Eu and downwelling irradiance Ed . It will be shown, from the radiative transfer equation, that the VSF of seawater can be calculated by the planar irradiances when the scattering phase <span class="hlt">function</span> of the suspended particles in the backward direction and the molecular VSF are known. On the derivation of the hydrosol VSF, several optical properties such as the absorption coefficient a ; the scattering coefficients of hydrosol, b , bf , bb and those of the suspended particles, bp , bfp , bbp ; the beam attenuation coefficient c ; the average cosines μ, μd , and μu ; and the backscattering shape factor for the downwelling light stream, rdu , will also be obtained. On the derivation of those optical parameters, classical knowledge related to interrelationships between inherent optical properties and apparent optical properties and obtained with Monte Carlo numerical simulations is analytically verified. The present theory can be applied to surface waters and any wavelengths, except for waters and wavelengths with an extremely low bb/a ratio.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoJI.210.1388X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoJI.210.1388X"><span>On the reliability of direct Rayleigh-wave estimation from multicomponent <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Zongbo; Mikesell, T. Dylan</p> <p>2017-09-01</p> <p>Seismic interferometry is routinely used to image and characterize underground geology. The vertical component <span class="hlt">cross-correlations</span> (CZZ) are often analysed in this process; although one can also use radial component and multicomponent <span class="hlt">cross-correlations</span> (CRR and CZR, respectively), which have been shown to provide a more accurate Rayleigh-wave Green's <span class="hlt">function</span> than CZZ when sources are unevenly distributed. In this letter, we identify the relationship between the multicomponent <span class="hlt">cross-correlations</span> (CZR and CRR) and the Rayleigh-wave Green's <span class="hlt">functions</span> to show why CZR and CRR are less sensitive than CZZ to non-stationary phase source energy. We demonstrate the robustness of CRR with a synthetic seismic noise data example. These results provide a compelling reason as to why CRR should be used to estimate the dispersive characteristics of the direct Rayleigh wave with seismic interferometry when the signal-to-noise ratio is high.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhRvE..89b3305O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhRvE..89b3305O"><span>Detrended <span class="hlt">cross-correlation</span> analysis consistently extended to multifractality</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oświȩcimka, Paweł; DroŻdŻ, Stanisław; Forczek, Marcin; Jadach, Stanisław; Kwapień, Jarosław</p> <p>2014-02-01</p> <p>We propose an algorithm, multifractal <span class="hlt">cross-correlation</span> analysis (MFCCA), which constitutes a consistent extension of the detrended <span class="hlt">cross-correlation</span> analysis and is able to properly identify and quantify subtle characteristics of multifractal <span class="hlt">cross-correlations</span> between two time series. Our motivation for introducing this algorithm is that the already existing methods, like multifractal extension, have at best serious limitations for most of the signals describing complex natural processes and often indicate multifractal <span class="hlt">cross-correlations</span> when there are none. The principal component of the present extension is proper incorporation of the sign of fluctuations to their generalized moments. Furthermore, we present a broad analysis of the model fractal stochastic processes as well as of the real-world signals and show that MFCCA is a robust and selective tool at the same time and therefore allows for a reliable quantification of the <span class="hlt">cross-correlative</span> structure of analyzed processes. In particular, it allows one to identify the boundaries of the multifractal scaling and to analyze a relation between the generalized Hurst exponent and the multifractal scaling parameter λq. This relation provides information about the character of potential multifractality in <span class="hlt">cross-correlations</span> and thus enables a deeper insight into dynamics of the analyzed processes than allowed by any other related method available so far. By using examples of time series from the stock market, we show that financial fluctuations typically <span class="hlt">cross-correlate</span> multifractally only for relatively large fluctuations, whereas small fluctuations remain mutually independent even at maximum of such <span class="hlt">cross-correlations</span>. Finally, we indicate possible utility of MFCCA to study effects of the time-lagged <span class="hlt">cross-correlations</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25353603','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25353603"><span>Detrended <span class="hlt">cross-correlation</span> analysis consistently extended to multifractality.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Oświecimka, Paweł; Drożdż, Stanisław; Forczek, Marcin; Jadach, Stanisław; Kwapień, Jarosław</p> <p>2014-02-01</p> <p>We propose an algorithm, multifractal <span class="hlt">cross-correlation</span> analysis (MFCCA), which constitutes a consistent extension of the detrended <span class="hlt">cross-correlation</span> analysis and is able to properly identify and quantify subtle characteristics of multifractal <span class="hlt">cross-correlations</span> between two time series. Our motivation for introducing this algorithm is that the already existing methods, like multifractal extension, have at best serious limitations for most of the signals describing complex natural processes and often indicate multifractal <span class="hlt">cross-correlations</span> when there are none. The principal component of the present extension is proper incorporation of the sign of fluctuations to their generalized moments. Furthermore, we present a broad analysis of the model fractal stochastic processes as well as of the real-world signals and show that MFCCA is a robust and selective tool at the same time and therefore allows for a reliable quantification of the <span class="hlt">cross-correlative</span> structure of analyzed processes. In particular, it allows one to identify the boundaries of the multifractal scaling and to analyze a relation between the generalized Hurst exponent and the multifractal scaling parameter λ(q). This relation provides information about the character of potential multifractality in <span class="hlt">cross-correlations</span> and thus enables a deeper insight into dynamics of the analyzed processes than allowed by any other related method available so far. By using examples of time series from the stock market, we show that financial fluctuations typically <span class="hlt">cross-correlate</span> multifractally only for relatively large fluctuations, whereas small fluctuations remain mutually independent even at maximum of such <span class="hlt">cross-correlations</span>. Finally, we indicate possible utility of MFCCA to study effects of the time-lagged <span class="hlt">cross-correlations</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1911916H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1911916H"><span>Correction of clock errors in seismic data using noise <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hable, Sarah; Sigloch, Karin; Barruol, Guilhem; Hadziioannou, Céline</p> <p>2017-04-01</p> <p>Correct and verifiable timing of seismic records is crucial for most seismological applications. For seismic land stations, frequent synchronization of the internal station clock with a GPS signal should ensure accurate timing, but loss of GPS synchronization is a common occurrence, especially for remote, temporary stations. In such cases, <span class="hlt">retrieval</span> of clock timing has been a long-standing problem. The same timing problem applies to Ocean Bottom Seismometers (OBS), where no GPS signal can be received during deployment and only two GPS synchronizations can be attempted upon deployment and recovery. If successful, a skew correction is usually applied, where the final timing deviation is interpolated linearly across the entire operation period. If GPS synchronization upon recovery fails, then even this simple and unverified, first-order correction is not possible. In recent years, the usage of <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> (CCFs) of ambient seismic noise has been demonstrated as a clock-correction method for certain network geometries. We demonstrate the great potential of this technique for island stations and OBS that were installed in the course of the Réunion Hotspot and Upper Mantle - Réunions Unterer Mantel (RHUM-RUM) project in the western Indian Ocean. Four stations on the island La Réunion were affected by clock errors of up to several minutes due to a missing GPS signal. CCFs are calculated for each day and compared with a reference <span class="hlt">cross-correlation</span> <span class="hlt">function</span> (RCF), which is usually the average of all CCFs. The clock error of each day is then determined from the measured shift between the daily CCFs and the RCF. To improve the accuracy of the method, CCFs are computed for several land stations and all three seismic components. Averaging over these station pairs and their 9 component pairs reduces the standard deviation of the clock errors by a factor of 4 (from 80 ms to 20 ms). This procedure permits a continuous monitoring of clock errors where small clock</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18643354','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18643354"><span>Multifractal detrended <span class="hlt">cross-correlation</span> analysis for two nonstationary signals.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhou, Wei-Xing</p> <p>2008-06-01</p> <p>We propose a method called multifractal detrended <span class="hlt">cross-correlation</span> analysis to investigate the multifractal behaviors in the power-law <span class="hlt">cross-correlations</span> between two time series or higher-dimensional quantities recorded simultaneously, which can be applied to diverse complex systems such as turbulence, finance, ecology, physiology, geophysics, and so on. The method is validated with <span class="hlt">cross-correlated</span> one- and two-dimensional binomial measures and multifractal random walks. As an example, we illustrate the method by analyzing two financial time series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD0716954','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD0716954"><span><span class="hlt">Functions</span> of a Man-Machine Interactive Information <span class="hlt">Retrieval</span> System</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p></p> <p>An effective man-machine interactive <span class="hlt">retrieval</span> system is not achieved by simply placing a terminal on each end of an existing machine <span class="hlt">retrieval</span>...many of these needs was developed and tested. The objective of the development of this system, BROWSER, was to investigate the effectiveness of a free...form query with a combinatorial search algorithm and the effectiveness of various techniques and components to facilitate online browsing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930013022','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930013022"><span>A proposal of fuzzy connective with learning <span class="hlt">function</span> and its application to fuzzy <span class="hlt">retrieval</span> system</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hayashi, Isao; Naito, Eiichi; Ozawa, Jun; Wakami, Noboru</p> <p>1993-01-01</p> <p>A new fuzzy connective and a structure of network constructed by fuzzy connectives are proposed to overcome a drawback of conventional fuzzy <span class="hlt">retrieval</span> systems. This network represents a <span class="hlt">retrieval</span> query and the fuzzy connectives in networks have a learning <span class="hlt">function</span> to adjust its parameters by data from a database and outputs of a user. The fuzzy <span class="hlt">retrieval</span> systems employing this network are also constructed. Users can <span class="hlt">retrieve</span> results even with a query whose attributes do not exist in a database schema and can get satisfactory results for variety of thinkings by learning <span class="hlt">function</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18274617','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18274617"><span>Autobiographical memory <span class="hlt">retrieval</span> and hippocampal activation as a <span class="hlt">function</span> of repetition and the passage of time.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nadel, Lynn; Campbell, Jenna; Ryan, Lee</p> <p>2007-01-01</p> <p>Multiple trace theory (MTT) predicts that hippocampal memory traces expand and strengthen as a <span class="hlt">function</span> of repeated memory <span class="hlt">retrievals</span>. We tested this hypothesis utilizing fMRI, comparing the effect of memory <span class="hlt">retrieval</span> versus the mere passage of time on hippocampal activation. While undergoing fMRI scanning, participants <span class="hlt">retrieved</span> remote autobiographical memories that had been previously <span class="hlt">retrieved</span> either one month earlier, two days earlier, or multiple times during the preceding month. Behavioral analyses revealed that the number and consistency of memory details <span class="hlt">retrieved</span> increased with multiple <span class="hlt">retrievals</span> but not with the passage of time. While all three <span class="hlt">retrieval</span> conditions activated a similar set of brain regions normally associated with autobiographical memory <span class="hlt">retrieval</span> including medial temporal lobe structures, hippocampal activation did not change as a <span class="hlt">function</span> of either multiple <span class="hlt">retrievals</span> or the passage of time. However, activation in other brain regions, including the precuneus, lateral prefrontal cortex, parietal cortex, lateral temporal lobe, and perirhinal cortex increased after multiple <span class="hlt">retrievals</span>, but was not influenced by the passage of time. These results have important implications for existing theories of long-term memory consolidation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2233815','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2233815"><span>Autobiographical Memory <span class="hlt">Retrieval</span> and Hippocampal Activation as a <span class="hlt">Function</span> of Repetition and the Passage of Time</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Nadel, Lynn; Campbell, Jenna; Ryan, Lee</p> <p>2007-01-01</p> <p>Multiple trace theory (MTT) predicts that hippocampal memory traces expand and strengthen as a <span class="hlt">function</span> of repeated memory <span class="hlt">retrievals</span>. We tested this hypothesis utilizing fMRI, comparing the effect of memory <span class="hlt">retrieval</span> versus the mere passage of time on hippocampal activation. While undergoing fMRI scanning, participants <span class="hlt">retrieved</span> remote autobiographical memories that had been previously <span class="hlt">retrieved</span> either one month earlier, two days earlier, or multiple times during the preceding month. Behavioral analyses revealed that the number and consistency of memory details <span class="hlt">retrieved</span> increased with multiple <span class="hlt">retrievals</span> but not with the passage of time. While all three <span class="hlt">retrieval</span> conditions activated a similar set of brain regions normally associated with autobiographical memory <span class="hlt">retrieval</span> including medial temporal lobe structures, hippocampal activation did not change as a <span class="hlt">function</span> of either multiple <span class="hlt">retrievals</span> or the passage of time. However, activation in other brain regions, including the precuneus, lateral prefrontal cortex, parietal cortex, lateral temporal lobe, and perirhinal cortex increased after multiple <span class="hlt">retrievals</span>, but was not influenced by the passage of time. These results have important implications for existing theories of long-term memory consolidation. PMID:18274617</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010IEITF..91.1031H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010IEITF..91.1031H"><span><span class="hlt">Cross-Correlation</span> by Single-bit Signal Processing for Ultrasonic Distance Measurement</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hirata, Shinnosuke; Kurosawa, Minoru Kuribayashi; Katagiri, Takashi</p> <p></p> <p>Ultrasonic distance measurement using the pulse-echo method is based on the determination of the time of flight of ultrasonic waves. The pulse-compression technique, in which the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> of a detected ultrasonic wave and a transmitted ultrasonic wave is obtained, is the conventional method used for improving the resolution of distance measurement. However, the calculation of a <span class="hlt">cross-correlation</span> operation requires high-cost digital signal processing. This paper presents a new method of sensor signal processing within the pulse-compression technique using a delta-sigma modulated single-bit digital signal. The proposed sensor signal processing method consists of a <span class="hlt">cross-correlation</span> operation employing single-bit signal processing and a smoothing operation involving a moving average filter. The proposed method reduces the calculation cost of the digital signal processing of the pulse-compression technique.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003CPL...372...35B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003CPL...372...35B"><span>Use of <span class="hlt">cross-correlated</span> NMR relaxation for the study of motional anisotropy of liquid crystals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bhattacharyya, Rangeet; Kumar, Anil</p> <p>2003-04-01</p> <p>A method to measure the rotational diffusion coefficients of a liquid crystal based on the measurements of auto and <span class="hlt">cross-correlated</span> relaxation is presented here. We report the measurements of <span class="hlt">cross-correlations</span> between the relaxation processes originating from the chemical shift anisotropy (CSA) of 13C and its dipolar coupling with the attached proton, for various carbons in a liquid crystal. The spectral densities are expressed as a <span class="hlt">function</span> of motional parameters, using extended Lipari-Szabo model-free approach. These motional parameters were extracted from the measured self-relaxation, cross-relaxation and the <span class="hlt">cross-correlation</span> rates. The potential of this method is demonstrated by the determination of the rotational diffusion coefficients of N-4-methoxybenzylidene-4-butylaniline (MBBA) at 297 K undergoing magic angle sample spinning.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..442...82X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..442...82X"><span><span class="hlt">Cross-correlation</span> analysis of stock markets using EMD and EEMD</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Mengjia; Shang, Pengjian; Lin, Aijing</p> <p>2016-01-01</p> <p>Empirical mode decomposition (EMD) is a data-driven signal analysis method for nonlinear and nonstationary data. Since it is intuitive, direct, posterior and adaptive, EMD is widely applied to various fields of study. In this paper, EMD and ensemble empirical mode decomposition (EEMD), a modified method of EMD, are applied to financial time series. Through analyzing the intrinsic mode <span class="hlt">functions</span> (IMFs) of EMD and EEMD, we find EEMD method performs better on the orthogonality of IMFs than EMD. With clustering the ordered frequencies of IMFs, the IMFs obtained from EEMD method are grouped into high-, medium-, and low-frequency components, representing the short-, medium-, and long-term volatilities of the index sequences, respectively. With the <span class="hlt">cross-correlation</span> analysis of DCCA <span class="hlt">cross-correlation</span> coefficient, our findings allow us to gain further and detailed insight into the <span class="hlt">cross-correlations</span> of stock markets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760011936','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760011936"><span>Strong scintillations in astrophysics. 4. <span class="hlt">Cross-correlation</span> between different frequencies and finite bandwidth effects</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lee, L. C.</p> <p>1976-01-01</p> <p>The <span class="hlt">cross</span> <span class="hlt">correlation</span> of the intensity fluctuations between different frequencies and finite bandwidth effects on the intensity correlations based on the Markov approximation were calculated. Results may be applied to quite general turbulence spectra for an extended turbulent medium. Calculations of the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> and of finite bandwidth effects are explicitly carried out for both Gaussian and Kolmogorov turbulence spectra. The increases of the correlation scale of intensity fluctuations are different for these two spectra and the difference can be used to determine whether the interstellar turbulent medium has a Gaussian or a Kolmogorov spectrum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4890042','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4890042"><span>Robust Statistical Detection of Power-Law <span class="hlt">Cross-Correlation</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Blythe, Duncan A. J.; Nikulin, Vadim V.; Müller, Klaus-Robert</p> <p>2016-01-01</p> <p>We show that widely used approaches in statistical physics incorrectly indicate the existence of power-law <span class="hlt">cross-correlations</span> between financial stock market fluctuations measured over several years and the neuronal activity of the human brain lasting for only a few minutes. While such <span class="hlt">cross-correlations</span> are nonsensical, no current methodology allows them to be reliably discarded, leaving researchers at greater risk when the spurious nature of <span class="hlt">cross-correlations</span> is not clear from the unrelated origin of the time series and rather requires careful statistical estimation. Here we propose a theory and method (PLCC-test) which allows us to rigorously and robustly test for power-law <span class="hlt">cross-correlations</span>, correctly detecting genuine and discarding spurious <span class="hlt">cross-correlations</span>, thus establishing meaningful relationships between processes in complex physical systems. Our method reveals for the first time the presence of power-law <span class="hlt">cross-correlations</span> between amplitudes of the alpha and beta frequency ranges of the human electroencephalogram. PMID:27250630</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21249986','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21249986"><span><span class="hlt">Cross-correlation</span> search for periodic gravitational waves</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dhurandhar, Sanjeev; Mukhopadhyay, Himan; Krishnan, Badri; Whelan, John T.</p> <p>2008-04-15</p> <p>In this paper we study the use of <span class="hlt">cross</span> <span class="hlt">correlations</span> between multiple gravitational wave (GW) data streams for detecting long-lived periodic signals. <span class="hlt">Cross-correlation</span> searches between data from multiple detectors have traditionally been used to search for stochastic GW signals, but recently they have also been used in directed searches for periodic GWs. Here we further adapt the <span class="hlt">cross-correlation</span> statistic for periodic GW searches by taking into account both the nonstationarity and the long-term-phase coherence of the signal. We study the statistical properties and sensitivity of this search and its relation to existing periodic wave searches, and describe the precise way in which the <span class="hlt">cross-correlation</span> statistic interpolates between semicoherent and fully coherent methods. Depending on the maximum duration over which we wish to preserve phase coherence, the <span class="hlt">cross-correlation</span> statistic can be tuned to go from a standard <span class="hlt">cross-correlation</span> statistic using data from distinct detectors, to the semicoherent time-frequency methods with increasing coherent time baselines, and all the way to a full coherent search. This leads to a unified framework for studying periodic wave searches and can be used to make informed trade-offs between computational cost, sensitivity, and robustness against signal uncertainties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960014587&hterms=Formula&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DFormula%2B1','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960014587&hterms=Formula&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DFormula%2B1"><span><span class="hlt">Cross</span> <span class="hlt">correlation</span> and length scales in turbulent flows near surfaces</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hunt, J. C. R.; Moin, P.; Lee, M.; Moser, R. D.; Spalart, P.; Mansour, N. N.; Kaimal, J. C.; Gaynor, E.</p> <p>1989-01-01</p> <p>Two kinds of length scales are used in turbulent flows; '<span class="hlt">functional</span> length scales' such as mixing length, dissipation length L(sub epsilon), etc., and 'flow-field length scales' derived from <span class="hlt">cross</span> <span class="hlt">correlations</span> of velocity, pressure, etc. in the flow. Some connection between these scales are derived here. We first consider the <span class="hlt">cross</span> <span class="hlt">correlation</span> R(sub vv)(y,y(sub 1)) of the normal components u at two heights y, y(sub 1) above a rigid surface, normalized by the velocity y(sub 1) (greater than y). For shear-free boundary layers it is found theoretically, and in field and numerical experiments that R(sub vv) approximately equals y/y(sub 1). For shear layers it is also found that R(sub vv) approximately equals f(y/y(sub 1)) less than or equal to y,y(sub 1). This <span class="hlt">function</span> f differs slightly between low Reynolds number numerical simulations and field experiments. The lateral structure defined by R(sub vv)(y,r(sub 3); y(sub 1),0) is also self similar and shows that the eddies centered at about y(sub 1) appear to have constant lateral width a(sub 3) above and below y(sub 1), where a(sub 3, sup +) approximately equals 7+1/(1.4dU(sup +)/dy(sup +)), when normalized on u(sub *) and v, where U is the mean velocity. Results for L(sub epsilon, sup -1) from direct numerical simulation are found to compare well with the formula L(sub epsilon, sup -1) = A(sub B)/y + A(sub S)dU/dy/v, for unidirectional and reversing turbulent boundary layers and channel flow, except near where dU/dy approximately equals 0. The conclusion is that the large-scale eddy structure and length scales in these flows are determined by a combination of shear and blocking, and that the vertical component of turbulence has a self-similar structure in both kinds of boundary layer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhyA..421..218K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhyA..421..218K"><span>On the interplay between short and long term memory in the power-law <span class="hlt">cross-correlations</span> setting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kristoufek, Ladislav</p> <p>2015-03-01</p> <p>We focus on emergence of the power-law <span class="hlt">cross-correlations</span> from processes with both short and long term memory properties. In the case of correlated error-terms, the power-law decay of the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> comes automatically with the characteristics of separate processes. Bivariate Hurst exponent is then equal to an average of separate Hurst exponents of the analyzed processes. Strength of short term memory has no effect on these asymptotic properties. Implications of these findings for the power-law <span class="hlt">cross-correlations</span> concept are further discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3305840','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3305840"><span><span class="hlt">Cross-Correlation</span>: An fMRI Signal-Processing Strategy</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hyde, James S.; Jesmanowicz, Andrzej</p> <p>2011-01-01</p> <p>The discovery of <span class="hlt">functional</span> MRI (fMRI), with the first papers appearing in 1992, gave rise to new categories of data that drove the development of new signal-processing strategies. Workers in the field were confronted with image time courses, which could be reshuffled to form pixel time courses. The waveform in an active pixel time-course was determined not only by the task sequence but also by the hemodynamic response <span class="hlt">function</span>. Reference waveforms could be <span class="hlt">cross-correlated</span> with pixel time courses to form an array of <span class="hlt">cross-correlation</span> coefficients. From this array of numbers, colorized images could be created and overlaid on anatomical images. An early paper from the authors’ laboratory is extensively reviewed here (Bandettini et al. 1993. Magn. Reson. Med. 30:161–173). That work was carried out using the vocabulary of vector algebra. <span class="hlt">Cross-correlation</span> methodology was central to the discovery of <span class="hlt">functional</span> connectivity MRI (fcMRI) by Biswal et al. (1995. Magn. Reson. Med. 34:537–541). In this method, a whole volume time course of images is collected while the brain is nominally at rest and connectivity is studied by <span class="hlt">cross-correlation</span> of pixel time courses. PMID:22051223</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015RvGeo..53..411B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015RvGeo..53..411B"><span>Stationary-phase integrals in the <span class="hlt">cross</span> <span class="hlt">correlation</span> of ambient noise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boschi, Lapo; Weemstra, Cornelis</p> <p>2015-06-01</p> <p>The <span class="hlt">cross</span> <span class="hlt">correlation</span> of ambient signal allows seismologists to collect data even in the absence of seismic events. "Seismic interferometry" shows that the <span class="hlt">cross</span> <span class="hlt">correlation</span> of simultaneous recordings of a random wavefield made at two locations is formally related to the impulse response between those locations. This idea has found many applications in seismology, as a growing number of dense seismic networks become available: <span class="hlt">cross-correlating</span> long seismic records, the Green's <span class="hlt">function</span> between instrument pairs is "reconstructed" and used, just like the seismic recording of an explosion, in tomography, monitoring, etc. These applications have been accompanied by theoretical investigations of the relationship between noise <span class="hlt">cross</span> <span class="hlt">correlation</span> and the Green's <span class="hlt">function</span>; numerous formulations of "ambient noise" theory have emerged, each based on different hypotheses and/or analytical approaches. The purpose of this study is to present most of those approaches together, providing a comprehensive overview of the theory. Understanding the specific hypotheses behind each Green's <span class="hlt">function</span> recipe is critical to its correct application. Hoping to guide nonspecialists who approach ambient noise theory for the first time, we treat the simplest formulation (the stationary-phase approximation applied to smooth unbounded media) in detail. We then move on to more general treatments, illustrating that the "stationary-phase" and "reciprocity theorem" approaches lead to the same formulae when applied to the same scenario. We show that a formal <span class="hlt">cross</span> <span class="hlt">correlation</span>/Green's <span class="hlt">function</span> relationship can be found in complex, bounded media and for nonuniform source distributions. We finally provide the bases for understanding how the Green's <span class="hlt">function</span> is reconstructed in the presence of scattering obstacles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JGRC..107.3160Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JGRC..107.3160Z"><span>Continuity preserving modified maximum <span class="hlt">cross-correlation</span> technique</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zavialov, Peter O.; Grigorieva, Julia V.; MöLler, Osmar O.; Kostianoy, Andrey G.; Gregoire, Marilaure</p> <p>2002-10-01</p> <p>The maximum <span class="hlt">cross-correlation</span> (MCC) method reconstructs the surface advective velocity fields from the displacements of spatial patterns in pairs of sequential satellite (normally infrared) images. However, the performance of the conventional MCC method is not always satisfactory. One of the main reasons for this is the fact that the method can correctly estimate only the velocity component parallel to the gradient of the property depicted in the images, while any small displacement perpendicular to the gradient (i.e., directed along the isolines) essentially maps the spatial pattern onto itself and therefore can not be detected using the conventional MCC technique. In the present work we propose a modification of the MCC method that allows circumventing this basic deficiency and improving the performance of the MCC technique. In this approach, the "cross-isoline" components of the velocity field are obtained as in the conventional MCC scheme; however, the "along-isoline" components derived from the MCC are disregarded as unreliable. Instead, the "true" along-isoline components are then reconstructed from the given cross-isoline velocity field based on the continuity requirement and on the condition of no normal flow at solid boundaries. This inverse problem is solved by constructing the two-dimensional stream <span class="hlt">function</span> in the curvilinear coordinate frame associated with the image isolines. The method is illustrated using AVHRR images from the southwestern Atlantic Ocean and the Black Sea. The results are compared with some direct drifter and current meter measurements and geostrophic estimates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996JMRB..110...26C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996JMRB..110...26C"><span><span class="hlt">Cross-Correlation</span> Effects on NMR Lineshapes and Peptide Conformation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Čuperlović, Miroslava; Palke, William E.; Gerig, J. T.; Gray, G. A.</p> <p>1996-01-01</p> <p>Information about molecular structure and dynamics can potentially be obtained by studying dipole-dipole and chemical-shift anisotropy (CSA) auto-correlation and dipole-CSA <span class="hlt">cross-correlation</span> effects in high-resolution NMR spectra. Equations for the lineshapes of the HNmultiplet in the fragment-15NH-CH- as a <span class="hlt">function</span> of NH-CH dihedral angle are derived by including these effects within the framework of the Redfield treatment of relaxation. To test the utility of the theoretical results,1H{15N} HSQC proton lineshape data for a variant of the enzyme staphylococcal nuclease in which all valine residues are labeled with15N have been analyzed to obtain the conformational angle (φ) between the N-H and adjacent C-H bonds. The results are generally in good agreement with values of φ obtained from crystal structure data. Considerations in the further development of the analysis of the lineshape of the HNmultiplet for experimental determinations of φ are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/993506','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/993506"><span>Magnified Weak Lensing <span class="hlt">Cross</span> <span class="hlt">Correlation</span> Tomography</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ulmer, Melville P., Clowe, Douglas I.</p> <p>2010-11-30</p> <p> nights on 4-m class telescopes, which gives concrete evidence of strong community support for this project. The WLT technique is based on the dependence of the gravitational shear signal on the angular diameter distances between the observer, the lens, and the lensed galaxy to measure cosmological parameters. By taking the ratio of measured shears of galaxies with different redshifts around the same lens, one obtains a measurement of the ratios of the angular diameter distances involved. Making these observations over a large range of lenses and background galaxy redshifts will measure the history of the expansion rate of the universe. Because this is a purely geometric measurement, it is insensitive to any form of evolution of objects or the necessity to understand the physics in the early universe. Thus, WLT was identified by the Dark Energy Task Force as perhaps the best method to measure the evolution of DE. To date, however, the conjecture of the DETF has not been experimentally verified, but will be by the proposed project. The primary reason for the lack of tomography measurements is that one must have an exceptional data-set to attempt the measurement. One needs both extremely good seeing (or space observations) in order to minimize the point spread <span class="hlt">function</span> smearing corrections on weak lensing shear measurements and deep, multi-color data, from B to z, to measure reliable photometric redshifts of the background galaxies being lensed (which are typically too faint to obtain spectroscopic redshifts). Because the entire process from multi-drizzling the HST images, and then creating shear maps, to gathering the necessary ground based observations, to generating photo-zs and then carrying out the tomography is a complicated task, until the creation of our team, nobody has taken the time to connect all the levels of expertise necessary to carry out this project based on HST archival data. Our data are being used in 2 Ph.D. theses. Kellen Murphy, at Ohio University, is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007APS..MARP38001T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007APS..MARP38001T"><span>An Ultra-Wideband <span class="hlt">Cross-Correlation</span> Radiometer for Mesoscopic Experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Toonen, Ryan; Haselby, Cyrus; Qin, Hua; Eriksson, Mark; Blick, Robert</p> <p>2007-03-01</p> <p>We have designed, built and tested a <span class="hlt">cross-correlation</span> radiometer for detecting statistical order in the quantum fluctuations of mesoscopic experiments at sub-Kelvin temperatures. Our system utilizes a fully analog front-end--operating over the X- and Ku-bands (8 to 18 GHz)--for computing the <span class="hlt">cross-correlation</span> <span class="hlt">function</span>. Digital signal processing techniques are used to provide robustness against instrumentation drifts and offsets. The economized version of our instrument can measure, with sufficient correlation efficiency, noise signals having power levels as low as 10 fW. We show that, if desired, we can improve this performance by including cryogenic preamplifiers which boost the signal-to-noise ratio near the signal source. By adding a few extra components, we can measure both the real and imaginary parts of the <span class="hlt">cross-correlation</span> <span class="hlt">function</span>--improving the overall signal-to-noise ratio by a factor of sqrt[2]. We demonstrate the utility of our <span class="hlt">cross-correlator</span> with noise power measurements from a quantum point contact.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S43A4511C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S43A4511C"><span>Estimation of the Mean Free Path using <span class="hlt">Cross-Correlations</span> in the Seismic Coda</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clerc, V.; Roux, P.; Campillo, M.; Maynard, R.; Chaput, J. A.</p> <p>2014-12-01</p> <p>We present recent results concerning the extraction of Green's <span class="hlt">functions</span> from coda waves. Campillo and Paul 2003 used earthquakes codas and found that the causal and anticausal parts of the <span class="hlt">cross-correlation</span> are asymmetrical for some stations, depending on the earthquake source region. The lapse time in the coda window is a key parameter to understand causal to anticausal amplitude ratio. We show that this ratio result from the competition between the source signature (non-symmetric <span class="hlt">cross-correlations</span> when the distribution of sources is non-isotropic around the receivers) and the scattering processes which tend to restore the time symmetry of the correlations. The theoretical analysis is derived from wave propagation theory for single scattering and multiple scattering as initiated by Roux 2005. We propose to use the temporal evolution of <span class="hlt">cross-correlation</span> <span class="hlt">function</span> amplitude in coda waves to estimate the value of the mean free path in the propagation medium. The equipartition of the energy is clearly observed in the numerical simulations conducted in a two-dimensional acoustic medium. The <span class="hlt">cross-correlations</span> between the distinct time windows in synthetic coda records at two points are measured for a set of events for which we obtain a good estimate of the medium mean free path. We perform the same analysis on a set of icequakes recorded at Mount Erebus. The correlations averaged over sources and time exhibit a temporal evolution that obeys to convergence patterns similar to those observed in numerical studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011EPJB...79...55O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011EPJB...79...55O"><span>Statistical properties of <span class="hlt">cross-correlation</span> in the Korean stock market</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oh, G.; Eom, C.; Wang, F.; Jung, W.-S.; Stanley, H. E.; Kim, S.</p> <p>2011-01-01</p> <p>We investigate the statistical properties of the <span class="hlt">cross-correlation</span> matrix between individual stocks traded in the Korean stock market using the random matrix theory (RMT) and observe how these affect the portfolio weights in the Markowitz portfolio theory. We find that the distribution of the <span class="hlt">cross-correlation</span> matrix is positively skewed and changes over time. We find that the eigenvalue distribution of original <span class="hlt">cross-correlation</span> matrix deviates from the eigenvalues predicted by the RMT, and the largest eigenvalue is 52 times larger than the maximum value among the eigenvalues predicted by the RMT. The β_{473} coefficient, which reflect the largest eigenvalue property, is 0.8, while one of the eigenvalues in the RMT is approximately zero. Notably, we show that the entropy <span class="hlt">function</span> E(σ) with the portfolio risk σ for the original and filtered <span class="hlt">cross-correlation</span> matrices are consistent with a power-law <span class="hlt">function</span>, E( σ) σ^{-γ}, with the exponent γ 2.92 and those for Asian currency crisis decreases significantly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28377210','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28377210"><span>Similar patterns of neural activity predict memory <span class="hlt">function</span> during encoding and <span class="hlt">retrieval</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kragel, James E; Ezzyat, Youssef; Sperling, Michael R; Gorniak, Richard; Worrell, Gregory A; Berry, Brent M; Inman, Cory; Lin, Jui-Jui; Davis, Kathryn A; Das, Sandhitsu R; Stein, Joel M; Jobst, Barbara C; Zaghloul, Kareem A; Sheth, Sameer A; Rizzuto, Daniel S; Kahana, Michael J</p> <p>2017-04-01</p> <p>Neural networks that span the medial temporal lobe (MTL), prefrontal cortex, and posterior cortical regions are essential to episodic memory <span class="hlt">function</span> in humans. Encoding and <span class="hlt">retrieval</span> are supported by the engagement of both distinct neural pathways across the cortex and common structures within the medial temporal lobes. However, the degree to which memory performance can be determined by neural processing that is common to encoding and <span class="hlt">retrieval</span> remains to be determined. To identify neural signatures of successful memory <span class="hlt">function</span>, we administered a delayed free-recall task to 187 neurosurgical patients implanted with subdural or intraparenchymal depth electrodes. We developed multivariate classifiers to identify patterns of spectral power across the brain that independently predicted successful episodic encoding and <span class="hlt">retrieval</span>. During encoding and <span class="hlt">retrieval</span>, patterns of increased high frequency activity in prefrontal, MTL, and inferior parietal cortices, accompanied by widespread decreases in low frequency power across the brain predicted successful memory <span class="hlt">function</span>. Using a cross-decoding approach, we demonstrate the ability to predict memory <span class="hlt">function</span> across distinct phases of the free-recall task. Furthermore, we demonstrate that classifiers that combine information from both encoding and <span class="hlt">retrieval</span> states can outperform task-independent models. These findings suggest that the engagement of a core memory network during either encoding or <span class="hlt">retrieval</span> shapes the ability to remember the past, despite distinct neural interactions that facilitate encoding and <span class="hlt">retrieval</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10117314','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10117314"><span><span class="hlt">Functions</span> and requirements for 105-KE Basin sludge <span class="hlt">retrieval</span> and packaging</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Feigenbutz, L.V.</p> <p>1994-12-16</p> <p>Sludge, and the clouding due to sludge, interferes with basin operation and maintenance activities. This document defines the overall <span class="hlt">functions</span> and requirements for sludge <span class="hlt">retrieval</span> and packaging activities to be performed in the 105-KE Basin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22375764','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22375764"><span>Weak lensing corrections to tSZ-lensing <span class="hlt">cross</span> <span class="hlt">correlation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tröster, Tilman; Waerbeke, Ludovic Van E-mail: waerbeke@phas.ubc.ca</p> <p>2014-11-01</p> <p>The <span class="hlt">cross</span> <span class="hlt">correlation</span> between the thermal Sunyaev-Zeldovich (tSZ) effect and gravitational lensing in wide field has recently been measured. It can be used to probe the distribution of the diffuse gas in large scale structure, as well as inform us about the missing baryons. As for any lensing-based quantity, higher order lensing effects can potentially affect the signal. Here, we extend previous higher order lensing calculations to the case of tSZ-lensing <span class="hlt">cross</span> <span class="hlt">correlations</span>. We derive terms analogous to corrections due to the Born approximation, lens-lens coupling, and reduced shear up to order ℓ ∼> 3000.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21251499','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21251499"><span>Polarization-assisted WMAP-NVSS <span class="hlt">Cross</span> <span class="hlt">Correlation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, G.-C.</p> <p>2008-10-10</p> <p><span class="hlt">Cross-correlation</span> of Cosmic Microwave Background (CMB) and large scale structure survey is one of the powerful tools for constraining the nature of dark energy through the so-called Integrated Sachs-Wolfe effect. However, CMB from higher redshift is the dominated noise of this effect. Here, we present the CMB polarization-assisted method to suppress this noise. We apply this method to <span class="hlt">cross-correlation</span> of the microwave sky observed by Wilkinson Microwave Anisotropy Probe (WMAP) with the radio source catalog compiled by NRAO VLA Sky Survey (NVSS) to study the efficiency of the noise suppression. We find that the spurious correlation is reduced about 2-7%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/886073','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/886073"><span>Optical <span class="hlt">cross-correlator</span> based on supercontinuum generation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Filip, Catalin V.; Toth, Csaba; Leemans, Wim P.</p> <p>2006-03-20</p> <p>A novel <span class="hlt">cross-correlator</span> that can be used for temporal characterization of femtosecond laser pulses has been developed. The correlation trace is obtained by ''sampling'' the structure of the laser pulse with a single, high-contrast pulse produced through femtosecond white-light generation in a line focus. This correlator has, therefore, fewer ''ghosts'' than a conventional third-order <span class="hlt">cross-correlator</span> and it can be used with laser pulses that span across a wide wavelength range. Both scanning and single-shot experimental arrangements are described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MNRAS.452.2149E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MNRAS.452.2149E"><span>Combining spectroscopic and photometric surveys using angular <span class="hlt">cross-correlations</span> - I. Algorithm and modelling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eriksen, Martin; Gaztañaga, Enrique</p> <p>2015-09-01</p> <p>Weak lensing (WL) clustering is studied using 2D (angular) coordinates, while redshift space distortions (RSD) and baryon acoustic oscillations (BAO) use 3D coordinates, which requires a model-dependent conversion of angles and redshifts into comoving distances. This is the first paper of a series, which explore modelling multi-tracer galaxy clustering (of WL, BAO and RSD), using only angular (2D) <span class="hlt">cross-correlations</span> in thin redshift bins. This involves evaluating many thousands <span class="hlt">cross-correlations</span>, each a multidimensional integral, which is computationally demanding. We present a new algorithm that performs these calculations as matrix operations. Nearby narrow redshift bins are intrinsically correlated, which can be used to recover the full (radial) 3D information. We show that the Limber approximation does not work well for this task. In the exact calculation, both the clustering amplitude and the RSD effect increase when decreasing the redshift bin width. For narrow bins, the <span class="hlt">cross-correlation</span> has a larger BAO peak than the auto-correlation because smaller scales are filtered out by the radial redshift separation. Moreover, the BAO peak shows a second (ghost) peak, shifted to smaller angles. We explore how WL, RSD and BAO contribute to the <span class="hlt">cross-correlations</span> as a <span class="hlt">function</span> of the redshift bin width and present a first exploration of non-linear effects and signal-to-noise ratio on these quantities. This illustrates that the new approach to clustering analysis provides new insights and is potentially viable in practice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4138331','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4138331"><span>Associative Encoding and <span class="hlt">Retrieval</span> Are Predicted by <span class="hlt">Functional</span> Connectivity in Distinct Hippocampal Area CA1 Pathways</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Duncan, Katherine; Tompary, Alexa</p> <p>2014-01-01</p> <p>Determining how the hippocampus supports the unique demands of memory encoding and <span class="hlt">retrieval</span> is fundamental for understanding the biological basis of episodic memory. One possibility proposed by theoretical models is that the distinct computational demands of encoding and <span class="hlt">retrieval</span> are accommodated by shifts in the <span class="hlt">functional</span> interaction between the hippocampal CA1 subregion and its input structures. However, empirical tests of this hypothesis are lacking. To test this in humans, we used high-resolution fMRI to measure <span class="hlt">functional</span> connectivity between hippocampal area CA1 and regions of the medial temporal lobe and midbrain during extended blocks of associative encoding and <span class="hlt">retrieval</span> tasks. We found evidence for a double dissociation between the pathways supporting successful encoding and <span class="hlt">retrieval</span>. Specifically, during the associative encoding task, but not the <span class="hlt">retrieval</span> task, <span class="hlt">functional</span> connectivity only between area CA1 and the ventral tegmental area predicted associative long-term memory. In contrast, connectivity between area CA1 and DG/CA3 was greater, on average, during the <span class="hlt">retrieval</span> task compared with the encoding task, and, importantly, the strength of this connectivity significantly correlated with <span class="hlt">retrieval</span> success. Together, these findings serve as an important first step toward understanding how the demands of fundamental memory processes may be met by changes in the relative strength of connectivity within hippocampal pathways. PMID:25143600</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhRvE..73c1915C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhRvE..73c1915C"><span><span class="hlt">Cross-correlation</span> of instantaneous phase increments in pressure-flow fluctuations: Applications to cerebral autoregulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Zhi; Hu, Kun; Stanley, H. Eugene; Novak, Vera; Ivanov, Plamen Ch.</p> <p>2006-03-01</p> <p>We investigate the relationship between the blood flow velocities (BFV) in the middle cerebral arteries and beat-to-beat blood pressure (BP) recorded from a finger in healthy and post-stroke subjects during the quasisteady state after perturbation for four different physiologic conditions: supine rest, head-up tilt, hyperventilation, and CO2 rebreathing in upright position. To evaluate whether instantaneous BP changes in the steady state are coupled with instantaneous changes in the BFV, we compare dynamical patterns in the instantaneous phases of these signals, obtained from the Hilbert transform, as a <span class="hlt">function</span> of time. We find that in post-stroke subjects the instantaneous phase increments of BP and BFV exhibit well-pronounced patterns that remain stable in time for all four physiologic conditions, while in healthy subjects these patterns are different, less pronounced, and more variable. We propose an approach based on the <span class="hlt">cross-correlation</span> of the instantaneous phase increments to quantify the coupling between BP and BFV signals. We find that the maximum correlation strength is different for the two groups and for the different conditions. For healthy subjects the amplitude of the <span class="hlt">cross-correlation</span> between the instantaneous phase increments of BP and BFV is small and attenuates within 3-5 heartbeats. In contrast, for post-stroke subjects, this amplitude is significantly larger and <span class="hlt">cross-correlations</span> persist up to 20 heartbeats. Further, we show that the instantaneous phase increments of BP and BFV are <span class="hlt">cross-correlated</span> even within a single heartbeat cycle. We compare the results of our approach with three complementary methods: direct BP-BFV <span class="hlt">cross-correlation</span>, transfer <span class="hlt">function</span> analysis, and phase synchronization analysis. Our findings provide insight into the mechanism of cerebral vascular control in healthy subjects, suggesting that this control mechanism may involve rapid adjustments (within a heartbeat) of the cerebral vessels, so that BFV remains steady in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhRvD..89d3516P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhRvD..89d3516P"><span>Cosmology from <span class="hlt">cross</span> <span class="hlt">correlation</span> of CMB lensing and galaxy surveys</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pearson, R.; Zahn, O.</p> <p>2014-02-01</p> <p>In recent years, <span class="hlt">cross</span> <span class="hlt">correlation</span> of lensing of the cosmic microwave background (CMB) with other large-scale structure (LSS) tracers has been used as a method to detect CMB lensing. Current experiments are also becoming sensitive enough to measure CMB lensing without the help of auxiliary tracers. As data quality improves rapidly, it has been suggested that the CMB lensing-LSS <span class="hlt">cross</span> <span class="hlt">correlation</span> may provide new insights into parameters describing cosmological structure growth. In this work, we perform forecasts that combine the lensing potential auto power spectrum from various future CMB experiments with the galaxy power spectrum from galaxy surveys, as well as the cross power spectrum between the two, marginalizing over a number of galactic and nongalactic cosmological parameters. We find that the CMB lensing-LSS <span class="hlt">cross</span> <span class="hlt">correlation</span> contains significant information on parameters such as the redshift distribution and bias of LSS tracers. We also find that the <span class="hlt">cross-correlation</span> information will lead to independent probes of cosmological parameters such as neutrino mass and the reionization optical depth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016CNSNS..40..163K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016CNSNS..40..163K"><span>Power-law <span class="hlt">cross-correlations</span> estimation under heavy tails</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kristoufek, Ladislav</p> <p>2016-11-01</p> <p>We examine the performance of six estimators of the power-law <span class="hlt">cross-correlations</span>-the detrended <span class="hlt">cross-correlation</span> analysis, the detrending moving-average <span class="hlt">cross-correlation</span> analysis, the height <span class="hlt">cross-correlation</span> analysis, the averaged periodogram estimator, the cross-periodogram estimator and the local cross-Whittle estimator-under heavy-tailed distributions. The selection of estimators allows to separate these into the time and frequency domain estimators. By varying the characteristic exponent of the α-stable distributions which controls the tails behavior, we report several interesting findings. First, the frequency domain estimators are practically unaffected by heavy tails bias-wise. Second, the time domain estimators are upward biased for heavy tails but they have lower estimator variance than the other group for short series. Third, specific estimators are more appropriate depending on distributional properties and length of the analyzed series. In addition, we provide a discussion of implications of these results for empirical applications as well as theoretical explanations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19710000223','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19710000223"><span>Atmospheric pollution measurement by optical <span class="hlt">cross</span> <span class="hlt">correlation</span> methods - A concept</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fisher, M. J.; Krause, F. R.</p> <p>1971-01-01</p> <p>Method combines standard spectroscopy with statistical <span class="hlt">cross</span> <span class="hlt">correlation</span> analysis of two narrow light beams for remote sensing to detect foreign matter of given particulate size and consistency. Method is applicable in studies of generation and motion of clouds, nuclear debris, ozone, and radiation belts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE10008E..02L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE10008E..02L"><span>Improved MODIS aerosol <span class="hlt">retrieval</span> in urban areas using a land classification approach and empirical orthogonal <span class="hlt">functions</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Levitan, Nathaniel; Gross, Barry</p> <p>2016-10-01</p> <p>New, high-resolution aerosol products are required in urban areas to improve the spatial coverage of the products, in terms of both resolution and <span class="hlt">retrieval</span> frequency. These new products will improve our understanding of the spatial variability of aerosols in urban areas and will be useful in the detection of localized aerosol emissions. Urban aerosol <span class="hlt">retrieval</span> is challenging for existing algorithms because of the high spatial variability of the surface reflectance, indicating the need for improved urban surface reflectance models. This problem can be stated in the language of novelty detection as the problem of selecting aerosol parameters whose effective surface reflectance spectrum is not an outlier in some space. In this paper, empirical orthogonal <span class="hlt">functions</span>, a reconstruction-based novelty detection technique, is used to perform single-pixel aerosol <span class="hlt">retrieval</span> using the single angular and temporal sample provided by the MODIS sensor. The empirical orthogonal basis <span class="hlt">functions</span> are trained for different land classes using the MODIS BRDF MCD43 product. Existing land classification products are used in training and aerosol <span class="hlt">retrieval</span>. The <span class="hlt">retrieval</span> is compared against the existing operational MODIS 3 KM Dark Target (DT) aerosol product and co-located AERONET data. Based on the comparison, our method allows for a significant increase in <span class="hlt">retrieval</span> frequency and a moderate decrease in the known biases of MODIS urban aerosol <span class="hlt">retrievals</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/10420550','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/10420550"><span>[The typological characteristics of higher nervous activity in dogs and the maxima of the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> between the electrical activities of the frontal cortex and the brain limbic systems].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chilingarian, L I</p> <p>1999-01-01</p> <p>Electrical activity of the frontal cortex, dorsal hippocampus, basolateral amygdala and lateral hypothalamus was recorded in eight dogs with chronically implanted electrodes. Mean values of the maxima of crosscorrelation <span class="hlt">function</span> (MCCF) between electrical potentials in the theta, alpha and beta-2 ranges were used as a basis for assessment of conditions for interaction between these structures. Typological features of the higher nervous activity were assessed by the animal performance under conditions of free choice of the reinforcement mode of a conditioned stimulus: either high probable but of low alimentary quality or with low probability but more valuable. The mean MCCF values in the theta range were higher than in the other ranges. The brain structure which had the high MCCF in the theta-range, at least, with two of the structures under study was considered as "dominant". It was shown that hippocampus was the dominant structure for melancholic dogs, the frontal cortex was in phlegmatics. The hypothalamus was shown to be the "dominant structure" in both sanguine and choleric animals, but, for the most part, its activity was correlated with different structures. Thus, conditions for interaction between the frontal cortex, hippocampus, amygdala and hypothalamus seem to be an important factor, which determines typological features of the higher nervous activity of dogs.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25769272','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25769272"><span><span class="hlt">Cross-correlation</span> of bio-signals using continuous wavelet transform and genetic algorithm.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sukiennik, Piotr; Białasiewicz, Jan T</p> <p>2015-05-30</p> <p>Continuous wavelet transform allows to obtain time-frequency representation of a signal and analyze short-lived temporal interaction of concurrent processes. That offers good localization in both time and frequency domain. Scalogram and coscalogram analysis of two signal interaction dynamics gives an indication of the <span class="hlt">cross-correlation</span> of analyzed signals in both domains. We have used genetic algorithm with a fitness <span class="hlt">function</span> based on signals convolution to find time delay between investigated signals. Two methods of <span class="hlt">cross-correlation</span> are proposed: one that finds single delay for analyzed signals, and one returns a vector of delay values for each of wavelet transform sub-band center frequencies. Algorithms were implemented using MATLAB. We have extracted the data of simultaneously recorded encephalogram and arterial blood pressure and have investigated their interaction dynamics. We found time delay whose value cannot be precisely determined by scalograms and coscalogram inspection. The biomedical signals used come from MIMIC database. <span class="hlt">Cross-correlation</span> of two complex signals is commonly performed using fast Fourier transform. It works well for signals with invariant frequency content. We have determined the time delay between analyzed signals using wavelet scalograms and we have accordingly shifted one of them, aligning associated events. Their coscalogram indicates the <span class="hlt">cross-correlation</span> of the associated events. Introducing new methods of wavelet transform in <span class="hlt">cross-correlation</span> analysis has proven to be beneficial to the gain of the information about process interaction. Introduced solutions could be used to reason about causality between processes and gain bigger insight regarding analyzed systems. Copyright © 2015 Elsevier B.V. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/65029','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/65029"><span><span class="hlt">Functional</span> design criteria, Project W-211, Initial Tank <span class="hlt">Retrieval</span> Systems. Revision 1</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rieck, C.A.</p> <p>1995-02-07</p> <p>This document provides the technical baseline for <span class="hlt">retrieval</span> of waste from ten double-shell tanks in the SY, AN, AP, AW, AY, and AZ tank farms. In order to <span class="hlt">retrieve</span> waste from these tanks, systems are needed to mix the sludge with the supernate and pump the waste mixture from the tank. For 101-SY, the existing mitigation pump will be used to mix the waste and Project W-211 will provide for waste removal. The <span class="hlt">retrieval</span> scope for the other nine tanks includes both the waste mixing and removal <span class="hlt">functions</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22352483','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22352483"><span>Spatial coherence and <span class="hlt">cross</span> <span class="hlt">correlation</span> of three-dimensional ambient noise fields in the ocean.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Walker, Shane C; Buckingham, Michael J</p> <p>2012-02-01</p> <p>Ambient acoustic noise fields in the ocean are generally three dimensional in that they exhibit vertical and horizontal directivity. A model of spatially homogeneous noise is introduced in which the directionality is treated as separable, that is, the overall directionality of the field is the product of the individual directivities in the horizontal and vertical. A uni-modal von Mises circular distribution from directional statistics is taken to represent the noise in the horizontal, whilst the vertical component is consistent with a surface distribution of vertical dipoles. An analysis of the coherence and <span class="hlt">cross</span> <span class="hlt">correlation</span> of the noise at two horizontally aligned sensors is developed. The coherence <span class="hlt">function</span> involves a single integral over finite limits, whilst the <span class="hlt">cross-correlation</span> <span class="hlt">function</span>, derived on the assumption that the noise has been pre-whitened, is given by an integral with limits that depend on the correlation delay time. Although the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> does not exhibit delta <span class="hlt">functions</span> that could be identified with the Green's <span class="hlt">function</span> for propagation between the two sensors in the field, it does drop abruptly to zero at numerical time delays equal to the travel time between the sensors. Hence the noise could be used to recover the sound speed in the medium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S13B2547N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S13B2547N"><span>Ambient Noise <span class="hlt">Cross-Correlation</span> Green's Tensor Analysis at The Geysers Geothermal Field, Northern California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nayak, A.; Taira, T.; Dreger, D. S.; Gritto, R.</p> <p>2016-12-01</p> <p>We <span class="hlt">retrieve</span> empirical Green's <span class="hlt">Functions</span> at The Geysers (TG) in the frequency range from 0.2 to 0.9 Hz for a wide range of interstation distances ranging between 1 to 25 km, corresponding to 0.23 to 5.7 times the wavelength. The Green's <span class="hlt">functions</span> are estimated from the <span class="hlt">cross-correlation</span> of ambient noise recorded by a variety of sensors (surface short-period, broadband, accelerometers, and borehole geophones) in and around the reservoir area. The methodology preserves the relative amplitudes of the different components of the 9-component Green's Tensor that allows us to directly compare Noise-derived Green's <span class="hlt">Functions</span> (NGFs) with normalized displacement waveforms of complete single-force Synthetic Green's <span class="hlt">Functions</span> (SGFs) computed assuming various 1D and 3D velocity models. In the T-Tangential, R-Radial, Z-Vertical reference frame the TT, RR, RZ, ZR and ZZ components (1st component: force direction, 2nd component: response direction) of NGFs show clear surface waves and even body wave phases for many station pairs and are remarkably similar to SGFs in waveform shape and relative amplitude at all distances. The NGFs are found to be broadly consistent with seismic velocity features inferred from body wave travel-times, and the TT component exhibits body wave geometrical spreading decay at distances < 3.5 km and surface wave decay at distances beyond 3.5 km. We find large anomalous amplitudes in TR, TZ, RT and ZT components of NGFs at small distances (< 4 km) that can be attributed to 10°-30° sensor misalignments at many stations inferred from analysis of long period teleseismic waveforms. After correcting for sensor misalignments, many NGFs for longer paths (> 8 km) across the center of the reservoir area still show significant amplitudes in these components. This region marks an increase in seismic velocities from the NW section to the SE section of TG along with a prominent low VP/VS ratio anomaly, and the 3D velocity model incorporating these features is able to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.S41A2372M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.S41A2372M"><span>On the linearity of <span class="hlt">cross-correlation</span> delay times</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mercerat, E. D.; Nolet, G.</p> <p>2012-12-01</p> <p>We investigate the question whether a P-wave delay time Δ T estimated by locating the maximum of the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> between data d(t) and a predicted test <span class="hlt">function</span> s(t): γ (t) = ∫ t1t_2 s(τ ) d(τ -t) \\ {d}τ, provides an estimate of the Delta T that is (quasi-)linear with the relative velocity perturbation deltaln V_P}. Such linearity is intuitive if the data d(t) is an undeformed but delayed replica of the test signal, i.e. if d(t)=s(t-Delta T). Then the maximum of gamma (t) is shifted exactly by the delay Delta T, and linearity holds even for Delta T very large. In this case, we say that the body waves are in the ray theoretical regime and their delays, because of Fermat's Principle, depend quasi-linearly on the relative velocity (or slowness) perturbations deltaln V_P in the model. However, even if we correct for dispersion induced by the instrument response and by attenuation, body waves may show frequency dependent delay times that are caused by diffraction effects around lateral heterogeneities. It is not a-priori clear that linearity holds for Delta T, as is assumed in finite-frequency theory, if the waveforms of d(t) and s(t) differ substantially because of such dispersion. To test the linearity, we generate synthetic seismograms between two boreholes, and between the boreholes and the surface, in a 3D box of 200 × 120 × 120 m. The heterogeneity is a checkerboard with cubic anomalies of size 12 × 12 × 12 m. We test two different anomaly amplitudes: ± 2% and ± 5%, and measure Delta T using a test seismogram s(t) computed for an homogeneous medium. We also predict the delays for the 5% model from those in the 2% model by multiplying with 5/2. These predictions are in error by 10-20% of the delay, which is usually acceptable for tomography when compared with actual data errors. A slight bias in the prediction indicates that the Wielandt effect - the fact that negative delays suffer less wavefront healing than positive delays - is a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27368774','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27368774"><span>A novel coefficient for detecting and quantifying asymmetry of California electricity market based on asymmetric detrended <span class="hlt">cross-correlation</span> analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Fang</p> <p>2016-06-01</p> <p>In order to detect and quantify asymmetry of two time series, a novel <span class="hlt">cross-correlation</span> coefficient is proposed based on recent asymmetric detrended <span class="hlt">cross-correlation</span> analysis (A-DXA), which we called A-DXA coefficient. The A-DXA coefficient, as an important extension of DXA coefficient ρDXA, contains two directional asymmetric <span class="hlt">cross-correlated</span> indexes, describing upwards and downwards asymmetric <span class="hlt">cross-correlations</span>, respectively. By using the information of directional covariance <span class="hlt">function</span> of two time series and directional variance <span class="hlt">function</span> of each series itself instead of power-law between the covariance <span class="hlt">function</span> and time scale, the proposed A-DXA coefficient can well detect asymmetry between the two series no matter whether the <span class="hlt">cross-correlation</span> is significant or not. By means of the proposed A-DXA coefficient conducted over the asymmetry for California electricity market, we found that the asymmetry between the prices and loads is not significant for daily average data in 1999 yr market (before electricity crisis) but extremely significant for those in 2000 yr market (during the crisis). To further uncover the difference of asymmetry between the years 1999 and 2000, a modified H statistic (MH) and ΔMH statistic are proposed. One of the present contributions is that the high MH values calculated for hourly data exist in majority months in 2000 market. Another important conclusion is that the <span class="hlt">cross-correlation</span> with downwards dominates over the whole 1999 yr in contrast to the <span class="hlt">cross-correlation</span> with upwards dominates over the 2000 yr.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Chaos..26f3109W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Chaos..26f3109W"><span>A novel coefficient for detecting and quantifying asymmetry of California electricity market based on asymmetric detrended <span class="hlt">cross-correlation</span> analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Fang</p> <p>2016-06-01</p> <p>In order to detect and quantify asymmetry of two time series, a novel <span class="hlt">cross-correlation</span> coefficient is proposed based on recent asymmetric detrended <span class="hlt">cross-correlation</span> analysis (A-DXA), which we called A-DXA coefficient. The A-DXA coefficient, as an important extension of DXA coefficient ρ D X A , contains two directional asymmetric <span class="hlt">cross-correlated</span> indexes, describing upwards and downwards asymmetric <span class="hlt">cross-correlations</span>, respectively. By using the information of directional covariance <span class="hlt">function</span> of two time series and directional variance <span class="hlt">function</span> of each series itself instead of power-law between the covariance <span class="hlt">function</span> and time scale, the proposed A-DXA coefficient can well detect asymmetry between the two series no matter whether the <span class="hlt">cross-correlation</span> is significant or not. By means of the proposed A-DXA coefficient conducted over the asymmetry for California electricity market, we found that the asymmetry between the prices and loads is not significant for daily average data in 1999 yr market (before electricity crisis) but extremely significant for those in 2000 yr market (during the crisis). To further uncover the difference of asymmetry between the years 1999 and 2000, a modified H statistic (MH) and ΔMH statistic are proposed. One of the present contributions is that the high MH values calculated for hourly data exist in majority months in 2000 market. Another important conclusion is that the <span class="hlt">cross-correlation</span> with downwards dominates over the whole 1999 yr in contrast to the <span class="hlt">cross-correlation</span> with upwards dominates over the 2000 yr.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4146561','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4146561"><span><span class="hlt">Cross-Correlation</span> Asymmetries and Causal Relationships between Stock and Market Risk</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Borysov, Stanislav S.; Balatsky, Alexander V.</p> <p>2014-01-01</p> <p>We study historical correlations and lead-lag relationships between individual stock risk (volatility of daily stock returns) and market risk (volatility of daily returns of a market-representative portfolio) in the US stock market. We consider the <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> averaged over all stocks, using 71 stock prices from the Standard & Poor's 500 index for 1994–2013. We focus on the behavior of the <span class="hlt">cross-correlations</span> at the times of financial crises with significant jumps of market volatility. The observed historical dynamics showed that the dependence between the risks was almost linear during the US stock market downturn of 2002 and after the US housing bubble in 2007, remaining at that level until 2013. Moreover, the averaged <span class="hlt">cross-correlation</span> <span class="hlt">function</span> often had an asymmetric shape with respect to zero lag in the periods of high correlation. We develop the analysis by the application of the linear response formalism to study underlying causal relations. The calculated response <span class="hlt">functions</span> suggest the presence of characteristic regimes near financial crashes, when the volatility of an individual stock follows the market volatility and vice versa. PMID:25162697</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25162697','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25162697"><span><span class="hlt">Cross-correlation</span> asymmetries and causal relationships between stock and market risk.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Borysov, Stanislav S; Balatsky, Alexander V</p> <p>2014-01-01</p> <p>We study historical correlations and lead-lag relationships between individual stock risk (volatility of daily stock returns) and market risk (volatility of daily returns of a market-representative portfolio) in the US stock market. We consider the <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> averaged over all stocks, using 71 stock prices from the Standard & Poor's 500 index for 1994-2013. We focus on the behavior of the <span class="hlt">cross-correlations</span> at the times of financial crises with significant jumps of market volatility. The observed historical dynamics showed that the dependence between the risks was almost linear during the US stock market downturn of 2002 and after the US housing bubble in 2007, remaining at that level until 2013. Moreover, the averaged <span class="hlt">cross-correlation</span> <span class="hlt">function</span> often had an asymmetric shape with respect to zero lag in the periods of high correlation. We develop the analysis by the application of the linear response formalism to study underlying causal relations. The calculated response <span class="hlt">functions</span> suggest the presence of characteristic regimes near financial crashes, when the volatility of an individual stock follows the market volatility and vice versa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AAS...22742608A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AAS...22742608A"><span>Intensity Mapping During Reionization: 21 cm and <span class="hlt">Cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aguirre, James E.; HERA Collaboration</p> <p>2016-01-01</p> <p>The first generation of 21 cm epoch of reionization (EoR) experiments are now reaching the sensitivities necessary for a detection of the power spectrum of plausible reionization models, and with the advent of next-generation capabilities (e.g. the Hydrogen Epoch of Reionization Array (HERA) and the Square Kilometer Array Phase I Low) will move beyond the power spectrum to imaging of the EoR intergalactic medium. Such datasets provide context to galaxy evolution studies for the earliest galaxies on scales of tens of Mpc, but at present wide, deep galaxy surveys are lacking, and attaining the depth to survey the bulk of galaxies responsible for reionization will be challenging even for JWST. Thus we seek useful <span class="hlt">cross-correlations</span> with other more direct tracers of the galaxy population. I review near-term prospects for <span class="hlt">cross-correlation</span> studies with 21 cm and CO and CII emission, as well as future far-infrared misions suchas CALISTO.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22373474','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22373474"><span>The Atacama Cosmology Telescope: <span class="hlt">cross</span> <span class="hlt">correlation</span> with Planck maps</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Louis, Thibaut; Calabrese, Erminia; Dunkley, Joanna; Næss, Sigurd; Addison, Graeme E.; Hincks, Adam D.; Hasselfield, Matthew; Hlozek, Renée; Bond, J. Richard; Hajian, Amir; Das, Sudeep; Devlin, Mark J.; Dünner, Rolando; Infante, Leopoldo; Gralla, Megan; Marriage, Tobias A.; Huffenberger, Kevin; Kosowsky, Arthur; Moodley, Kavilan; Niemack, Michael D.; and others</p> <p>2014-07-01</p> <p>We present the temperature power spectrum of the Cosmic Microwave Background obtained by <span class="hlt">cross-correlating</span> maps from the Atacama Cosmology Telescope (ACT) at 148 and 218 GHz with maps from the Planck satellite at 143 and 217 GHz, in two overlapping regions covering 592 square degrees. We find excellent agreement between the two datasets at both frequencies, quantified using the variance of the residuals between the ACT power spectra and the ACT × Planck cross-spectra. We use these <span class="hlt">cross-correlations</span> to measure the calibration of the ACT data at 148 and 218 GHz relative to Planck, to 0.7% and 2% precision respectively. We find no evidence for anisotropy in the calibration parameter. We compare the Planck 353 GHz power spectrum with the measured amplitudes of dust and cosmic infrared background (CIB) of ACT data at 148 and 218 GHz. We also compare planet and point source measurements from the two experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23149036','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23149036"><span>Altered brain <span class="hlt">function</span> underlying verbal memory encoding and <span class="hlt">retrieval</span> in psychotic major depression.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kelley, Ryan; Garrett, Amy; Cohen, Jeremy; Gomez, Rowena; Lembke, Anna; Keller, Jennifer; Reiss, Allan L; Schatzberg, Alan</p> <p>2013-02-28</p> <p>Psychotic major depression (PMD) is associated with deficits in verbal memory as well as other cognitive impairments. This study investigated brain <span class="hlt">function</span> in individuals with PMD during a verbal declarative memory task. Participants included 16 subjects with PMD, 15 subjects with non-psychotic major depression (NPMD) and 16 healthy controls (HC). <span class="hlt">Functional</span> magnetic resonance imaging (fMRI) data were acquired while subjects performed verbal memory encoding and <span class="hlt">retrieval</span> tasks. During the explicit encoding task, subjects semantically categorized words as either "man-made" or "not man-made." For the <span class="hlt">retrieval</span> task, subjects identified whether words had been presented during the encoding task. <span class="hlt">Functional</span> MRI data were processed using SPM5 and a group by condition ANOVA. Clusters of activation showing either a significant main effect of group or an interaction of group by condition were further examined using t-tests to identify group differences. During the encoding task, the PMD group showed lower hippocampus, insula, and prefrontal activation compared to HC. During the <span class="hlt">retrieval</span> task, the PMD group showed lower recognition accuracy and higher prefrontal and parietal cortex activation compared to both HC and NPMD groups. Verbal <span class="hlt">retrieval</span> deficits in PMD may be associated with deficient hippocampus <span class="hlt">function</span> during encoding. Increased brain activation during <span class="hlt">retrieval</span> may reflect an attempt to compensate for encoding deficits. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19257417','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19257417"><span>Deterministic <span class="hlt">retrieval</span> of complex Green's <span class="hlt">functions</span> using hard X rays.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vine, D J; Paganin, D M; Pavlov, K M; Uesugi, K; Takeuchi, A; Suzuki, Y; Yagi, N; Kämpfe, T; Kley, E-B; Förster, E</p> <p>2009-01-30</p> <p>A massively parallel deterministic method is described for reconstructing shift-invariant complex Green's <span class="hlt">functions</span>. As a first experimental implementation, we use a single phase contrast x-ray image to reconstruct the complex Green's <span class="hlt">function</span> associated with Bragg reflection from a thick perfect crystal. The reconstruction is in excellent agreement with a classic prediction of dynamical diffraction theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..APR.Y5003O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..APR.Y5003O"><span>CMB lensing from SPT+Planck and <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Omori, Yuuki; SPT Collaboration; DES Collaboration</p> <p>2017-01-01</p> <p>The South Pole Telescope (SPT) SZ survey has observed 2500 square degrees of the Cosmic Microwave Background (CMB) to high accuracy down to 1 arcminute resolution at 150GHz. The Planck satellite has also observed the same patch of the CMB sky at 143GHz, but the two experiments were designed to measure temperature anisotropies optimally at different angular scales. By combining data from these two experiments, we are able to produce a temperature map that has an improved signal-to-noise ratio at all scales. This combined temperature map is used to produce a CMB weak lensing map, which we use for cosmological parameter and <span class="hlt">cross-correlation</span> analyses. In particular, the SPT footprint has significant overlap with the Dark Energy Survey (DES) observing region, which allows us to <span class="hlt">cross-correlate</span> the CMB lensing map with galaxy density and galaxy shear measurements obtained by DES. In this talk, I will present the SPT+Planck combining procedure, the CMB lensing reconstruction pipeline, tests performed to verify the lensing map, and finally the <span class="hlt">cross-correlation</span> measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950037376&hterms=activity+series&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dactivity%2Bseries','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950037376&hterms=activity+series&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dactivity%2Bseries"><span><span class="hlt">Cross-correlation</span> of point series using a new method</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Strothers, Richard B.</p> <p>1994-01-01</p> <p>Traditional methods of <span class="hlt">cross-correlation</span> of two time series do not apply to point time series. Here, a new method, devised specifically for point series, utilizes a correlation measure that is based in the rms difference (or, alternatively, the median absolute difference) between nearest neightbors in overlapped segments of the two series. Error estimates for the observed locations of the points, as well as a systematic shift of one series with respect to the other to accommodate a constant, but unknown, lead or lag, are easily incorporated into the analysis using Monte Carlo techniques. A methodological restriction adopted here is that one series be treated as a template series against which the other, called the target series, is <span class="hlt">cross-correlated</span>. To estimate a significance level for the correlation measure, the adopted alternative (null) hypothesis is that the target series arises from a homogeneous Poisson process. The new method is applied to <span class="hlt">cross-correlating</span> the times of the greatest geomagnetic storms with the times of maximum in the undecennial solar activity cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JAtS...59..335I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JAtS...59..335I"><span>Aerosol <span class="hlt">Retrievals</span> from Individual AVHRR Channels. Part II: Quality Control, Probability Distribution <span class="hlt">Functions</span>, Information Content, and Consistency Checks of <span class="hlt">Retrievals</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ignatov, Alexander; Stowe, Larry</p> <p>2002-02-01</p> <p>This second part of a two-part study evaluates <span class="hlt">retrievals</span> of aerosol optical depths, 1 and 2, in Advanced Very High Resolution Radiometer (AVHRR) channels 1 and 2 centered at 1 = 0.63 and 2 = 0.83 m, and an effective Ångström exponent, , derived therefrom as = ln(1/2)/ln(1/2). The <span class="hlt">retrievals</span> are made with the Second Simulation of the Satellite Signal in the Solar Spectrum (6S) radiative transfer model from four NOAA-14 AVHRR datasets, collected between February 1998 and May 1999 in the latitudinal belt of 5°-25°S. A series of quality control (QC) checks applied to the <span class="hlt">retrievals</span> to identify outliers are described. These remove a total of 1% of points, which presumably originate from channel misregistration, residual cloud in AVHRR cloud-screened pixels, and substantial deviations from the assumptions used in the <span class="hlt">retrieval</span> model (e.g., bright coastal and high altitude inland waters). First, from examining histograms of the derived parameters it is found that and are accurately fit by lognormal and normal probability distribution <span class="hlt">functions</span> (PDFs), respectively. Second, the scattergrams 1 versus 2 are analyzed to see if they form a coherent pattern. They do indeed converge at the origin, as expected, but frequently are outside of the expected domain in <IMG border="0" src="/charent/GREEK/UNACCENTED/LOWERCASE/tauI.gif">1-<IMG border="0" src="/charent/GREEK/UNACCENTED/LOWERCASE/tauI.gif">2 space, defined by two straight lines corresponding to <IMG border="0" src="/charent/GREEK/UNACCENTED/LOWERCASE/alphaI.gif"> = 0 and <IMG border="0" src="/charent/GREEK/UNACCENTED/LOWERCASE/alphaI.gif"> = 2. This results in a low bias in <IMG border="0" src="/charent/GREEK/UNACCENTED/LOWERCASE/alphaI.gif">, which tends to fill in an interval of <IMG border="0" src="/charent/GREEK/UNACCENTED/LOWERCASE/alphaI.gif"> <IMG border="0" src="/charent/ISO_CHARACTERS_MIXED/LOWERCASE/isin.gif"> [<IMG border="0" src="/charent/ISO_CHARACTERS_MIXED/LOWERCASE/minus.gif">1, 1] rather than <IMG</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/249296','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/249296"><span>Three dimensional winds: A maximum <span class="hlt">cross-correlation</span> application to elastic lidar data</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Buttler, William Tillman</p> <p>1996-05-01</p> <p>Maximum <span class="hlt">cross-correlation</span> techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum <span class="hlt">cross-correlation</span> technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a <span class="hlt">function</span> of range and altitude from incoherent elastic backscatter lidar (light detection and ranging) data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three-dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain-following winds in the Rio Grande valley.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996PhDT........51B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996PhDT........51B"><span>Three-Dimensional Winds: a Maximum <span class="hlt">Cross-Correlation</span> Application to Elastic LIDAR Data.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buttler, William Tillman</p> <p></p> <p>Maximum <span class="hlt">cross-correlation</span> techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum <span class="hlt">cross-correlation</span> technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a <span class="hlt">function</span> of range and altitude from incoherent elastic back-scatter lidar (light detection and ranging) data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three-dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain -following winds in the Rio Grande valley.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19163061','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19163061"><span>Peri-event <span class="hlt">cross-correlation</span> over time for analysis of interactions in neuronal firing.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Paiva, António R C; Park, Il; Sanchez, Justin C; Príncipe, José C</p> <p>2008-01-01</p> <p>Several methods have been described in the literature to verify the presence of couplings between neurons in the brain. In this paper we introduce the peri-event <span class="hlt">cross-correlation</span> over time (PECCOT) to describe the interaction among the two neurons as a <span class="hlt">function</span> of the event onset. Instead of averaging over time, the PECCOT averages the <span class="hlt">cross-correlation</span> over instances of the event. As a consequence, the PECCOT is able to characterize with high temporal resolution the interactions over time among neurons. To illustrate the method, the PECCOT is applied to a simulated dataset and for analysis of synchrony in recordings of a rat performing a go/no go behavioral lever press task. We verify the presence of synchrony before the lever press time and its suppression afterwards.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5139993','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5139993"><span>Structure beyond pair correlations: X-ray <span class="hlt">cross-correlation</span> from colloidal crystals1</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lehmkühler, Felix; Fischer, Birgit; Müller, Leonard; Ruta, Beatrice; Grübel, Gerhard</p> <p>2016-01-01</p> <p>The results of an X-ray <span class="hlt">cross-correlation</span> analysis (XCCA) study on hard-sphere colloidal crystals and glasses are presented. The article shows that <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> can be used to extract structural information beyond the static structure factor in such systems. In particular, the powder average can be overcome by accessing the crystals’ unit-cell structure. In this case, the results suggest that the crystal is of face-centered cubic type. It is demonstrated that XCCA is a valuable tool for X-ray crystallography, in particular for studies on colloidal systems. These are typically characterized by a rather poor crystalline quality due to size polydispersity and limitations in experimental resolution because of the small q values probed. Furthermore, nontrivial correlations are observed that allow a more detailed insight into crystal structures beyond conventional crystallography, especially to extend knowledge in structure formation processes and phase transitions. PMID:27980511</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JMagR.155...29M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JMagR.155...29M"><span><span class="hlt">Cross-Correlation</span> Effects Involving Curie Spin Relaxation in Methyl Groups</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Madhu, P. K.; Mandal, Pravat K.; Müller, Norbert</p> <p>2002-03-01</p> <p><span class="hlt">Cross-correlation</span> effects arising in methyl protons due to the simultaneous presence of dipole-dipole, chemical shift anisotropy, and Curie spin relaxation mechanisms in paramagnetic systems are analyzed. We assess the potential of obtaining structural constraints from the <span class="hlt">cross-correlation</span> of Curie spin relaxation with dipolar relaxation mechanisms among methyl proton spins. By theoretical analysis and numerical simulations we characterize the transfer <span class="hlt">functions</span> describing the interconversion processes of different ranks of multispin order. The time dependence of these processes contains a new type of structural information, the orientation of the methyl C3-axis with respect to the electron center. Experimental confirmation is found for selected methyl groups in low spin Fe3+ sperm whale myoglobin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3756987','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3756987"><span>Dissociable Temporo-Parietal Memory Networks Revealed by <span class="hlt">Functional</span> Connectivity during Episodic <span class="hlt">Retrieval</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hirose, Satoshi; Kimura, Hiroko M.; Jimura, Koji; Kunimatsu, Akira; Abe, Osamu; Ohtomo, Kuni; Miyashita, Yasushi; Konishi, Seiki</p> <p>2013-01-01</p> <p>Episodic memory <span class="hlt">retrieval</span> most often recruits multiple separate processes that are thought to involve different temporal regions. Previous studies suggest dissociable regions in the left lateral parietal cortex that are associated with the <span class="hlt">retrieval</span> processes. Moreover, studies using resting-state <span class="hlt">functional</span> connectivity (RSFC) have provided evidence for the temporo-parietal memory networks that may support the <span class="hlt">retrieval</span> processes. In this <span class="hlt">functional</span> MRI study, we tested <span class="hlt">functional</span> significance of the memory networks by examining <span class="hlt">functional</span> connectivity of brain activity during episodic <span class="hlt">retrieval</span> in the temporal and parietal regions of the memory networks. Recency judgments, judgments of the temporal order of past events, can be achieved by at least two <span class="hlt">retrieval</span> processes, relational and item-based. Neuroimaging results revealed several temporal and parietal activations associated with relational/item-based recency judgments. Significant RSFC was observed between one parahippocampal region and one left lateral parietal region associated with relational recency judgments, and between four lateral temporal regions and another left lateral parietal region associated with item-based recency judgments. <span class="hlt">Functional</span> connectivity during task was found to be significant between the parahippocampal region and the parietal region in the RSFC network associated with relational recency judgments. However, out of the four tempo-parietal RSFC networks associated with item-based recency judgments, only one of them (between the left posterior lateral temporal region and the left lateral parietal region) showed significant <span class="hlt">functional</span> connectivity during task. These results highlight the contrasting roles of the parahippocampal and the lateral temporal regions in recency judgments, and suggest that only a part of the tempo-parietal RSFC networks are recruited to support particular <span class="hlt">retrieval</span> processes. PMID:24009657</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhRvE..84a6106J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhRvE..84a6106J"><span>Multifractal detrending moving-average <span class="hlt">cross-correlation</span> analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiang, Zhi-Qiang; Zhou, Wei-Xing</p> <p>2011-07-01</p> <p>There are a number of situations in which several signals are simultaneously recorded in complex systems, which exhibit long-term power-law <span class="hlt">cross</span> <span class="hlt">correlations</span>. The multifractal detrended <span class="hlt">cross-correlation</span> analysis (MFDCCA) approaches can be used to quantify such <span class="hlt">cross</span> <span class="hlt">correlations</span>, such as the MFDCCA based on the detrended fluctuation analysis (MFXDFA) method. We develop in this work a class of MFDCCA algorithms based on the detrending moving-average analysis, called MFXDMA. The performances of the proposed MFXDMA algorithms are compared with the MFXDFA method by extensive numerical experiments on pairs of time series generated from bivariate fractional Brownian motions, two-component autoregressive fractionally integrated moving-average processes, and binomial measures, which have theoretical expressions of the multifractal nature. In all cases, the scaling exponents hxy extracted from the MFXDMA and MFXDFA algorithms are very close to the theoretical values. For bivariate fractional Brownian motions, the scaling exponent of the <span class="hlt">cross</span> <span class="hlt">correlation</span> is independent of the <span class="hlt">cross-correlation</span> coefficient between two time series, and the MFXDFA and centered MFXDMA algorithms have comparative performances, which outperform the forward and backward MFXDMA algorithms. For two-component autoregressive fractionally integrated moving-average processes, we also find that the MFXDFA and centered MFXDMA algorithms have comparative performances, while the forward and backward MFXDMA algorithms perform slightly worse. For binomial measures, the forward MFXDMA algorithm exhibits the best performance, the centered MFXDMA algorithms performs worst, and the backward MFXDMA algorithm outperforms the MFXDFA algorithm when the moment order q<0 and underperforms when q>0. We apply these algorithms to the return time series of two stock market indexes and to their volatilities. For the returns, the centered MFXDMA algorithm gives the best estimates of hxy(q) since its hxy(2) is closest to 0</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21867256','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21867256"><span>Multifractal detrending moving-average <span class="hlt">cross-correlation</span> analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jiang, Zhi-Qiang; Zhou, Wei-Xing</p> <p>2011-07-01</p> <p>There are a number of situations in which several signals are simultaneously recorded in complex systems, which exhibit long-term power-law <span class="hlt">cross</span> <span class="hlt">correlations</span>. The multifractal detrended <span class="hlt">cross-correlation</span> analysis (MFDCCA) approaches can be used to quantify such <span class="hlt">cross</span> <span class="hlt">correlations</span>, such as the MFDCCA based on the detrended fluctuation analysis (MFXDFA) method. We develop in this work a class of MFDCCA algorithms based on the detrending moving-average analysis, called MFXDMA. The performances of the proposed MFXDMA algorithms are compared with the MFXDFA method by extensive numerical experiments on pairs of time series generated from bivariate fractional Brownian motions, two-component autoregressive fractionally integrated moving-average processes, and binomial measures, which have theoretical expressions of the multifractal nature. In all cases, the scaling exponents h(xy) extracted from the MFXDMA and MFXDFA algorithms are very close to the theoretical values. For bivariate fractional Brownian motions, the scaling exponent of the <span class="hlt">cross</span> <span class="hlt">correlation</span> is independent of the <span class="hlt">cross-correlation</span> coefficient between two time series, and the MFXDFA and centered MFXDMA algorithms have comparative performances, which outperform the forward and backward MFXDMA algorithms. For two-component autoregressive fractionally integrated moving-average processes, we also find that the MFXDFA and centered MFXDMA algorithms have comparative performances, while the forward and backward MFXDMA algorithms perform slightly worse. For binomial measures, the forward MFXDMA algorithm exhibits the best performance, the centered MFXDMA algorithms performs worst, and the backward MFXDMA algorithm outperforms the MFXDFA algorithm when the moment order q<0 and underperforms when q>0. We apply these algorithms to the return time series of two stock market indexes and to their volatilities. For the returns, the centered MFXDMA algorithm gives the best estimates of h(xy)(q) since its h(xy)(2) is closest</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3838950','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3838950"><span><span class="hlt">Functional</span> anatomy of temporal organisation and domain-specificity of episodic memory <span class="hlt">retrieval</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kwok, Sze Chai; Shallice, Tim; Macaluso, Emiliano</p> <p>2013-01-01</p> <p>Episodic memory provides information about the “when” of events as well as “what” and “where” they happened. Using <span class="hlt">functional</span> imaging, we investigated the domain specificity of <span class="hlt">retrieval</span>-related processes following encoding of complex, naturalistic events. Subjects watched a 42-min TV episode, and 24 h later, made discriminative choices of scenes from the clip during fMRI. Subjects were presented with two scenes and required to either choose the scene that happened earlier in the film (Temporal), or the scene with a correct spatial arrangement (Spatial), or the scene that had been shown (Object). We identified a <span class="hlt">retrieval</span> network comprising the precuneus, lateral and dorsal parietal cortex, middle frontal and medial temporal areas. The precuneus and angular gyrus are associated with temporal <span class="hlt">retrieval</span>, with precuneal activity correlating negatively with temporal distance between two happenings at encoding. A dorsal fronto-parietal network engages during spatial <span class="hlt">retrieval</span>, while antero-medial temporal regions activate during object-related <span class="hlt">retrieval</span>. We propose that access to episodic memory traces involves different processes depending on task requirements. These include memory-searching within an organised knowledge structure in the precuneus (Temporal task), online maintenance of spatial information in dorsal fronto-parietal cortices (Spatial task) and combining scene-related spatial and non-spatial information in the hippocampus (Object task). Our findings support the proposal of process-specific dissociations of <span class="hlt">retrieval</span>. PMID:22877840</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22877840','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22877840"><span><span class="hlt">Functional</span> anatomy of temporal organisation and domain-specificity of episodic memory <span class="hlt">retrieval</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kwok, Sze Chai; Shallice, Tim; Macaluso, Emiliano</p> <p>2012-10-01</p> <p>Episodic memory provides information about the "when" of events as well as "what" and "where" they happened. Using <span class="hlt">functional</span> imaging, we investigated the domain specificity of <span class="hlt">retrieval</span>-related processes following encoding of complex, naturalistic events. Subjects watched a 42-min TV episode, and 24h later, made discriminative choices of scenes from the clip during fMRI. Subjects were presented with two scenes and required to either choose the scene that happened earlier in the film (Temporal), or the scene with a correct spatial arrangement (Spatial), or the scene that had been shown (Object). We identified a <span class="hlt">retrieval</span> network comprising the precuneus, lateral and dorsal parietal cortex, middle frontal and medial temporal areas. The precuneus and angular gyrus are associated with temporal <span class="hlt">retrieval</span>, with precuneal activity correlating negatively with temporal distance between two happenings at encoding. A dorsal fronto-parietal network engages during spatial <span class="hlt">retrieval</span>, while antero-medial temporal regions activate during object-related <span class="hlt">retrieval</span>. We propose that access to episodic memory traces involves different processes depending on task requirements. These include memory-searching within an organised knowledge structure in the precuneus (Temporal task), online maintenance of spatial information in dorsal fronto-parietal cortices (Spatial task) and combining scene-related spatial and non-spatial information in the hippocampus (Object task). Our findings support the proposal of process-specific dissociations of <span class="hlt">retrieval</span>. Copyright © 2012 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMNS42A..03L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMNS42A..03L"><span>Simulation of GPR Passive Interferometry using <span class="hlt">Cross-correlation</span> for LNAPL Model Monitoring Application</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, J.; Zeng, Z.; Liu, F.</p> <p>2011-12-01</p> <p>Passive interferometry is based on the relation between the reflection and the transmission responses of the subsurface. The transmission response can be received at surface in the presence of the non-artificial source in the subsurface. The reflection response can be obtained by the <span class="hlt">cross-correlation</span> or Multi-dimensional deconvolution (MDD) of the transmission response. In this paper, we investigate the basic principles of synthesizing the virtual shot gathers record from the transmission response and design a finite-difference algorithm for the simulation of long-duration GPR measurements in the presence of passive source randomly spaced in the subsurface. The random noise sources have the characteristic including random duration time, random waveform and random position distribution. Here we apply the GPR passive interferometry in light non-aqueous phase liquid (LNAPL) model monitoring and use the <span class="hlt">cross-correlation</span> method to <span class="hlt">retrieve</span> the target signal. With the simulation result, we can accurately obtain the dielectric constant, EM velocity, dynamic monitoring change characteristics and other information of LNAPL model by common midpoint (CMP) velocity analysis and normal moveout correction (NMO) method. The result demonstrates that the passive GPR interferometry is feasible in subsurface LNAPL and other target monitoring. It provides an idea and foundation for real passive interferometry GPR application.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22280725','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22280725"><span>A passive inverse filter for Green's <span class="hlt">function</span> <span class="hlt">retrieval</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gallot, Thomas; Catheline, Stefan; Roux, Philippe; Campillo, Michel</p> <p>2012-01-01</p> <p>Passive methods for the recovery of Green's <span class="hlt">functions</span> from ambient noise require strong hypotheses, including isotropic distribution of the noise sources. Very often, this distribution is nonisotropic, which introduces bias in the Green's <span class="hlt">function</span> reconstruction. To minimize this bias, a spatiotemporal inverse filter is proposed. The method is tested on a directive noise field computed from an experimental active seismic data set. The results indicate that the passive inverse filter allows the manipulation of the spatiotemporal degrees of freedom of a complex wave field, and it can efficiently compensate for the noise wavefield directivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..394...47D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..394...47D"><span>Strong anticipation and long-range <span class="hlt">cross-correlation</span>: Application of detrended <span class="hlt">cross-correlation</span> analysis to human behavioral data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Delignières, Didier; Marmelat, Vivien</p> <p>2014-01-01</p> <p>In this paper, we analyze empirical data, accounting for coordination processes between complex systems (bimanual coordination, interpersonal coordination, and synchronization with a fractal metronome), by using a recently proposed method: detrended <span class="hlt">cross-correlation</span> analysis (DCCA). This work is motivated by the strong anticipation hypothesis, which supposes that coordination between complex systems is not achieved on the basis of local adaptations (i.e., correction, predictions), but results from a more global matching of complexity properties. Indeed, recent experiments have evidenced a very close correlation between the scaling properties of the series produced by two coordinated systems, despite a quite weak local synchronization. We hypothesized that strong anticipation should result in the presence of long-range <span class="hlt">cross-correlations</span> between the series produced by the two systems. Results allow a detailed analysis of the effects of coordination on the fluctuations of the series produced by the two systems. In the long term, series tend to present similar scaling properties, with clear evidence of long-range <span class="hlt">cross-correlation</span>. Short-term results strongly depend on the nature of the task. Simulation studies allow disentangling the respective effects of noise and short-term coupling processes on DCCA results, and suggest that the matching of long-term fluctuations could be the result of short-term coupling processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28951163','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28951163"><span>Dynamic changes in large-scale <span class="hlt">functional</span> network organization during autobiographical memory <span class="hlt">retrieval</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Inman, Cory S; James, G Andrew; Vytal, Katherine; Hamann, Stephan</p> <p>2017-09-23</p> <p>Autobiographical memory (AM), episodic memory for life events, involves the orchestration of multiple dynamic cognitive processes, including memory access and subsequent elaboration. Previous neuroimaging studies have contrasted memory access and elaboration processes in terms of regional brain activation and connectivity within large, multi-region networks. Although interactions between key memory-related regions such as the hippocampus and prefrontal cortex (PFC) have been shown to play an important role in AM <span class="hlt">retrieval</span>, it remains unclear how such connectivity between specific, individual regions involved in AM <span class="hlt">retrieval</span> changes dynamically across the <span class="hlt">retrieval</span> process and how these changes relate to broader memory networks throughout the whole brain. The present <span class="hlt">functional</span> magnetic resonance imaging (fMRI) study sought to assess the specific changes in interregional connectivity patterns across the AM <span class="hlt">retrieval</span> processes to understand network level mechanisms of AM <span class="hlt">retrieval</span> and further test current theoretical accounts of dynamic AM <span class="hlt">retrieval</span> processes. We predicted that dynamic connections would reflect two hypothesized memory processes, with initial processes reflecting memory-access related connections between regions such as the anterior hippocampal and ventrolateral PFC regions, and later processes reflecting elaboration-related connections between dorsolateral frontal working memory regions and parietal-occipital visual imagery regions. One week prior to fMRI scanning, fifteen healthy adult participants generated AMs using personally selected cue words. During scanning, participants were cued to <span class="hlt">retrieve</span> the AMs. We used a moving-window <span class="hlt">functional</span> connectivity analysis and graph theoretic measures to examine dynamic changes in the strength and centrality of connectivity among regions involved in AM <span class="hlt">retrieval</span>. Consistent with predictions, early, access-related processing primarily involved a ventral frontal to temporal-parietal network associated with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28040020','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28040020"><span>Effect of dispersion on the convergence rate for Green's <span class="hlt">function</span> <span class="hlt">retrieval</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yoritomo, John Y; Weaver, Richard L</p> <p>2016-12-01</p> <p>Much information about wave propagation in a variety of structures has been obtained from Green's <span class="hlt">function</span> <span class="hlt">retrieval</span> by noise correlation. Here it is examined how dispersion affects Green's <span class="hlt">function</span> <span class="hlt">retrieval</span> and, in particular, its signal-to-noise ratio (SNR). On recalling how the inherent spread of a signal due to band limitation is augmented by spread due to dispersion and propagation distance, and how both affect amplitude, it is argued that SNR in highly dispersive media can be substantially lowered by strong dispersion. It is argued that this is most relevant for gravity waves over large propagation distances in the ocean or atmosphere. In particular, it is discussed that dispersion could explain recent <span class="hlt">retrieval</span> failure from surface gravity wave noise in the ocean. Methods are considered to ameliorate the poor SNR due to dispersion. Numerical simulation is used to substantiate the analytic results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25680583','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25680583"><span><span class="hlt">Functional</span> interactions between dentate gyrus, striatum and anterior thalamic nuclei on spatial memory <span class="hlt">retrieval</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Méndez-Couz, M; Conejo, N M; González-Pardo, H; Arias, J L</p> <p>2015-04-24</p> <p>The standard model of memory system consolidation supports the temporal reorganization of brain circuits underlying long-term memory storage, including interactions between the dorsal hippocampus and extra-hippocampal structures. In addition, several brain regions have been suggested to be involved in the <span class="hlt">retrieval</span> of spatial memory. In particular, several authors reported a possible role of the ventral portion of the hippocampus together with the thalamus or the striatum in the persistence of this type of memory. Accordingly, the present study aimed to evaluate the contribution of different cortical and subcortical brain regions, and neural networks involved in spatial memory <span class="hlt">retrieval</span>. For this purpose, we used cytochrome c oxidase quantitative histochemistry as a reliable method to measure brain oxidative metabolism. Animals were trained in a hidden platform task and tested for memory retention immediately after the last training session; one week after completing the task, they were also tested in a memory <span class="hlt">retrieval</span> probe. Results showed that <span class="hlt">retrieval</span> of the previously learned task was associated with increased levels of oxidative metabolism in the prefrontal cortex, the dorsal and ventral striatum, the anterodorsal thalamic nucleus and the dentate gyrus of the dorsal and ventral hippocampus. The analysis of <span class="hlt">functional</span> interactions between brain regions suggest that the dorsal and ventral dentate gyrus could be involved in spatial memory <span class="hlt">retrieval</span>. In addition, the results highlight the key role of the extended hippocampal system, thalamus and striatum in this process. Our study agrees with previous ones reporting interactions between the dorsal hippocampus and the prefrontal cortex during spatial memory <span class="hlt">retrieval</span>. Furthermore, novel activation patterns of brain networks involving the aforementioned regions were found. These <span class="hlt">functional</span> brain networks could underlie spatial memory <span class="hlt">retrieval</span> evaluated in the Morris water maze task.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014MNRAS.445..437M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014MNRAS.445..437M"><span>A method for the estimation of the significance of <span class="hlt">cross-correlations</span> in unevenly sampled red-noise time series</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Max-Moerbeck, W.; Richards, J. L.; Hovatta, T.; Pavlidou, V.; Pearson, T. J.; Readhead, A. C. S.</p> <p>2014-11-01</p> <p>We present a practical implementation of a Monte Carlo method to estimate the significance of <span class="hlt">cross-correlations</span> in unevenly sampled time series of data, whose statistical properties are modelled with a simple power-law power spectral density. This implementation builds on published methods; we introduce a number of improvements in the normalization of the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> estimate and a bootstrap method for estimating the significance of the <span class="hlt">cross-correlations</span>. A closely related matter is the estimation of a model for the light curves, which is critical for the significance estimates. We present a graphical and quantitative demonstration that uses simulations to show how common it is to get high <span class="hlt">cross-correlations</span> for unrelated light curves with steep power spectral densities. This demonstration highlights the dangers of interpreting them as signs of a physical connection. We show that by using interpolation and the Hanning sampling window <span class="hlt">function</span> we are able to reduce the effects of red-noise leakage and to recover steep simple power-law power spectral densities. We also introduce the use of a Neyman construction for the estimation of the errors in the power-law index of the power spectral density. This method provides a consistent way to estimate the significance of <span class="hlt">cross-correlations</span> in unevenly sampled time series of data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24568865','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24568865"><span>Unraveling Brain <span class="hlt">Functional</span> Connectivity of encoding and <span class="hlt">retrieval</span> in the context of education.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Panda, Rajanikant; Bharath, Rose Dawn; George, Lija; Kanungo, Silpa; Reddy, Rajakumari P; Upadhyay, Neeraj; Thamodharan, Arumugam; Rajeshwaran, Jamuna; Rao, Shobini L; Gupta, Arun Kumar</p> <p>2014-04-01</p> <p>Human memory is an enigmatic component of cognition which many researchers have attempted to comprehend. Accumulating studies on <span class="hlt">functional</span> connectivity see brain as a complex dynamic unit with positively and negatively correlated networks in perfect coherence during a task. We aimed to examine coherence of network connectivity during visual memory encoding and <span class="hlt">retrieval</span> in the context of education. School Educated (SE) and College Educated (CE) healthy volunteers (n=60) were recruited and assessed for visual encoding and <span class="hlt">retrieval</span>. <span class="hlt">Functional</span> connectivity using seed to voxel based connectivity analysis of the posterior cingulate cortex (PCC) was evaluated. We noticed that there were reciprocal dynamic changes in both dorsolateral prefrontal cortex (DLPFC) region and PCC regions during working memory encoding and <span class="hlt">retrieval</span>. In agreement with the previous studies, there were more positively correlated regions during <span class="hlt">retrieval</span> compared to encoding. The default mode network (DMN) networks showed greater negative correlations during more attentive task of visual encoding. In tune with the recent studies on cognitive reserve we also found that number of years of education was a significant factor influencing working memory connectivity. SE had higher positive correlation to DLPFC region and lower negative correlation to DMN in comparison with CE during encoding and <span class="hlt">retrieval</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.464.2120S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.464.2120S"><span><span class="hlt">Cross-correlating</span> Planck CMB lensing with SDSS: lensing-lensing and galaxy-lensing <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singh, Sukhdeep; Mandelbaum, Rachel; Brownstein, Joel R.</p> <p>2017-01-01</p> <p>We present results from <span class="hlt">cross-correlating</span> Planck cosmic microwave background (CMB) lensing maps with the Sloan Digital Sky Survey (SDSS) galaxy lensing shape catalogue and BOSS (Baryon Oscillation Spectroscopic Survey) galaxy catalogues. For galaxy position versus CMB lensing <span class="hlt">cross-correlations</span>, we measure the convergence signal around the galaxies in configuration space, using the BOSS LOWZ (z ˜ 0.30) and CMASS (z ˜ 0.57) samples. With fixed Planck 2015 cosmology, doing a joint fit with the galaxy clustering measurement, for the LOWZ (CMASS) sample we find a galaxy bias bg = 1.75 ± 0.04 (1.95 ± 0.02) and galaxy-matter <span class="hlt">cross-correlation</span> coefficient rcc = 1.0 ± 0.2 (0.8 ± 0.1) using 20 < rp < 70 h-1 Mpc, consistent with results from galaxy-galaxy lensing. Using the same scales and including the galaxy-galaxy lensing measurements, we constrain Ωm = 0.284 ± 0.024 and relative calibration bias between the CMB lensing and galaxy lensing to be b_γ =0.82^{+0.15}_{-0.14}. The combination of galaxy lensing and CMB lensing also allows us to measure the cosmological distance ratios (with zl ˜ 0.3, zs ˜ 0.5) R=D_s D_{l,*}/D_{* D_{l,s}}=2.68± 0.29, consistent with predictions from the Planck 2015 cosmology (R=2.35). We detect the galaxy position-CMB convergence <span class="hlt">cross-correlation</span> at small scales, rp < 1 h-1 Mpc, and find consistency with lensing by NFW haloes of mass Mh ˜ 1013 h-1 M⊙. Finally, we measure the CMB lensing-galaxy shear <span class="hlt">cross-correlation</span>, finding an amplitude of A = 0.76 ± 0.23 (zeff = 0.35, θ < 2°) with respect to Planck 2015 Λ cold dark matter predictions (1σ level consistency). We do not find evidence for relative systematics between the CMB and SDSS galaxy lensing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.470.3220W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.470.3220W"><span>Determining the H i content of galaxies via intensity mapping <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wolz, L.; Blake, C.; Wyithe, J. S. B.</p> <p>2017-09-01</p> <p>We propose an innovative method for measuring the neutral hydrogen (H i) content of an optically selected spectroscopic sample of galaxies through <span class="hlt">cross-correlation</span> with H i intensity mapping measurements. We show that the H i-galaxy cross-power spectrum contains an additive shot noise term that scales with the average H i brightness temperature of the optically selected galaxies, allowing constraints to be placed on the average H i mass per galaxy. This approach can estimate the H i content of populations too faint to directly observe through their 21-cm emission over a wide range of redshifts. This <span class="hlt">cross-correlation</span>, as a <span class="hlt">function</span> of optical luminosity or colour, can be used to derive H i-scaling relations. We demonstrate that this signal will be detectable by <span class="hlt">cross-correlating</span> upcoming Australian Square Kilometre Array Pathfinder observations with existing optically selected samples. We also use semi-analytic simulations to verify that the H i mass can be successfully recovered by our technique in the range M_{H I} > 10^8 M_{⊙}, in a manner independent of the underlying power spectrum shape. We conclude that this method is a powerful tool to study galaxy evolution, which only requires a single intensity mapping data set to infer complementary H i gas information from existing optical and infrared observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4326781','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4326781"><span>Near-Field Fluorescence <span class="hlt">Cross-Correlation</span> Spectroscopy on Planar Membranes</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2015-01-01</p> <p>The organization and dynamics of plasma membrane components at the nanometer scale are essential for biological <span class="hlt">functions</span> such as transmembrane signaling and endocytosis. Planarized nanoscale apertures in a metallic film are demonstrated as a means of confining the excitation light for multicolor fluorescence spectroscopy to a 55 ± 10 nm beam waist. This technique provides simultaneous two-color, subdiffraction-limited fluorescence correlation spectroscopy and fluorescence <span class="hlt">cross-correlation</span> spectroscopy on planar membranes. The fabrication and implementation of this technique are demonstrated for both model membranes and live cells. Membrane-bound proteins were observed to cluster upon the addition of a multivalent cross-linker: On supported lipid bilayers, clusters of cholera toxin subunit B were formed upon cross-linking by an antibody specific for this protein; on living cells, immunoglobulin E bound to its receptor (FcεRI) on the plasma membranes of RBL mast cells was observed to form clusters upon exposure to a trivalent antigen. The formation of membrane clusters was quantified via fluorescence intensity vs time and changes in the temporal auto- and <span class="hlt">cross-correlations</span> above a single nanoscale aperture. The illumination profile from a single aperture is analyzed experimentally and computationally with a rim-dominated illumination profile, yielding no change in the autocorrelation dwell time with changes in aperture diameter from 60 to 250 nm. This near-field fluorescence <span class="hlt">cross-correlation</span> methodology provides access to nanoscale details of dynamic membrane interactions and motivates further development of near-field optical methods. PMID:25004429</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.461.4353L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.461.4353L"><span>Modelling Lyman α forest <span class="hlt">cross-correlations</span> with LyMAS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lochhaas, Cassandra; Weinberg, David H.; Peirani, Sébastien; Dubois, Yohan; Colombi, Stéphane; Blaizot, Jérémy; Font-Ribera, Andreu; Pichon, Christophe; Devriendt, Julien</p> <p>2016-10-01</p> <p>We use the Lyα Mass Association Scheme (LyMAS) to predict <span class="hlt">cross-correlations</span> at z = 2.5 between dark matter haloes and transmitted flux in the Lyα forest, and compare to <span class="hlt">cross-correlations</span> measured for quasars and damped Lyα systems (DLAs) from the Baryon Oscillation Spectroscopic Survey (BOSS) by Font-Ribera et al. We calibrate LyMAS using Horizon-AGN hydrodynamical cosmological simulations of a (100 h- 1 Mpc)3 comoving volume. We apply this calibration to a (1 h- 1 Gpc)3 simulation realized with 20483 dark matter particles. In the 100 h- 1 Mpc box, LyMAS reproduces the halo-flux correlations computed from the full hydrodynamic gas distribution very well. In the 1 h- 1 Gpc box, the amplitude of the large-scale <span class="hlt">cross-correlation</span> tracks the halo bias bh as expected. We provide empirical fitting <span class="hlt">functions</span> that describe our numerical results. In the transverse separation bins used for the BOSS analyses, LyMAS <span class="hlt">cross-correlation</span> predictions follow linear theory accurately down to small scales. Fitting the BOSS measurements requires inclusion of random velocity errors; we find best-fitting rms velocity errors of 399 and 252 {km} {s}^{-1} for quasars and DLAs, respectively. We infer bias-weighted mean halo masses of M_h/10^{12} h^{-1} M_{⊙}=2.19^{+0.16}_{-0.15} and 0.69^{+0.16}_{-0.14} for the host haloes of quasars and DLAs, with ˜0.2 dex systematic uncertainty associated with redshift evolution, intergalactic medium parameters, and selection of data fitting range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002PhRvE..65f6126P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002PhRvE..65f6126P"><span>Random matrix approach to <span class="hlt">cross</span> <span class="hlt">correlations</span> in financial data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Plerou, Vasiliki; Gopikrishnan, Parameswaran; Rosenow, Bernd; Amaral, Luís A.; Guhr, Thomas; Stanley, H. Eugene</p> <p>2002-06-01</p> <p>We analyze <span class="hlt">cross</span> <span class="hlt">correlations</span> between price fluctuations of different stocks using methods of random matrix theory (RMT). Using two large databases, we calculate <span class="hlt">cross-correlation</span> matrices <ss>C</ss> of returns constructed from (i) 30-min returns of 1000 US stocks for the 2-yr period 1994-1995, (ii) 30-min returns of 881 US stocks for the 2-yr period 1996-1997, and (iii) 1-day returns of 422 US stocks for the 35-yr period 1962-1996. We test the statistics of the eigenvalues λi of <ss>C</ss> against a ``null hypothesis'' - a random correlation matrix constructed from mutually uncorrelated time series. We find that a majority of the eigenvalues of <ss>C</ss> fall within the RMT bounds [λ-,λ+] for the eigenvalues of random correlation matrices. We test the eigenvalues of <ss>C</ss> within the RMT bound for universal properties of random matrices and find good agreement with the results for the Gaussian orthogonal ensemble of random matrices-implying a large degree of randomness in the measured <span class="hlt">cross-correlation</span> coefficients. Further, we find that the distribution of eigenvector components for the eigenvectors corresponding to the eigenvalues outside the RMT bound display systematic deviations from the RMT prediction. In addition, we find that these ``deviating eigenvectors'' are stable in time. We analyze the components of the deviating eigenvectors and find that the largest eigenvalue corresponds to an influence common to all stocks. Our analysis of the remaining deviating eigenvectors shows distinct groups, whose identities correspond to conventionally identified business sectors. Finally, we discuss applications to the construction of portfolios of stocks that have a stable ratio of risk to return.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009SPIE.7386E..0FP','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009SPIE.7386E..0FP"><span>Cell recognition by image processing and nonlinear <span class="hlt">cross</span> <span class="hlt">correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pérez-Careta, E.; Torres-Cisneros, M.; Sánchez-Mondragón, J. J.; Vázquez Buenos Aires, O.; Ibarra Manzano, O. G.; Aguilera-Cortés, L. A.</p> <p>2009-06-01</p> <p>This work implements a novel hybrid method for detection and tracking of biological cells of "in vitro" samples (Goobic,1 2005). The method is able to detect and track cells based on image processing, nonlinear filters and normalized <span class="hlt">cross</span> <span class="hlt">correlation</span> (ncc) and it is tested on a full sequence of 1080 images of cell cultures. In addition of the cell speed, Cell tracking differentiate itself from tracking other kinds of tracking because cells show: mitosis, apthosis, overlapping and migration (Liao,2 1995). Image processing provides an excellent tool to improve cell recognition and background elimination, set as a priori task on this work and conveniently implemented by a Fourier analysis. The normal <span class="hlt">cross</span> <span class="hlt">correlation</span> was developed in the Fourier space to reduce time processing. The problem of the target detection was formulated as a nonlinear joint detection/estimation problem on the position parameters. A bank of spatially and temporally localized nonlinear filters is used to estimate the a posteriori likelihood of the existence of the target in a given space-time resolution cell. The shapes of the targets are random and according to the sequence, the targets change of shape almost every frame. However, the <span class="hlt">cross</span> <span class="hlt">correlation</span> result is based on the target shape matching, not in the position; and the system is invariant to rotation. Nonlinear filter makes a robust cell tracking method by producing a sharper correlation peak and reducing the false positives in the correlation. These false positives may also be reduced by using image preprocessing. Fourier and nonlinear filtering implementation showed the best results for the proposed cell tracking method presenting the best time consumption and the best cell localization.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12188802','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12188802"><span>Random matrix approach to <span class="hlt">cross</span> <span class="hlt">correlations</span> in financial data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Plerou, Vasiliki; Gopikrishnan, Parameswaran; Rosenow, Bernd; Amaral, Luís A Nunes; Guhr, Thomas; Stanley, H Eugene</p> <p>2002-06-01</p> <p>We analyze <span class="hlt">cross</span> <span class="hlt">correlations</span> between price fluctuations of different stocks using methods of random matrix theory (RMT). Using two large databases, we calculate <span class="hlt">cross-correlation</span> matrices C of returns constructed from (i) 30-min returns of 1000 US stocks for the 2-yr period 1994-1995, (ii) 30-min returns of 881 US stocks for the 2-yr period 1996-1997, and (iii) 1-day returns of 422 US stocks for the 35-yr period 1962-1996. We test the statistics of the eigenvalues lambda(i) of C against a "null hypothesis"--a random correlation matrix constructed from mutually uncorrelated time series. We find that a majority of the eigenvalues of C fall within the RMT bounds [lambda(-),lambda(+)] for the eigenvalues of random correlation matrices. We test the eigenvalues of C within the RMT bound for universal properties of random matrices and find good agreement with the results for the Gaussian orthogonal ensemble of random matrices-implying a large degree of randomness in the measured <span class="hlt">cross-correlation</span> coefficients. Further, we find that the distribution of eigenvector components for the eigenvectors corresponding to the eigenvalues outside the RMT bound display systematic deviations from the RMT prediction. In addition, we find that these "deviating eigenvectors" are stable in time. We analyze the components of the deviating eigenvectors and find that the largest eigenvalue corresponds to an influence common to all stocks. Our analysis of the remaining deviating eigenvectors shows distinct groups, whose identities correspond to conventionally identified business sectors. Finally, we discuss applications to the construction of portfolios of stocks that have a stable ratio of risk to return.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JSMTE..03..037A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JSMTE..03..037A"><span><span class="hlt">Cross-correlation</span> of long-range correlated series</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arianos, Sergio; Carbone, Anna</p> <p>2009-03-01</p> <p>A method for estimating the <span class="hlt">cross-correlation</span> Cxy(τ) of long-range correlated series x(t) and y(t), at varying lags τ and scales n, is proposed. For fractional Brownian motions with Hurst exponents H1 and H2, the asymptotic expression for Cxy(τ) depends only on the lag τ (wide-sense stationarity) and scales as a power of n with exponent H1+H2 for \\tau \\rightarrow 0 . The method is illustrated on: (i) financial series, to show the leverage effect; (ii) genomic sequences, to estimate the correlations between structural parameters along the chromosomes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22458430','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22458430"><span>Axion inflation with <span class="hlt">cross-correlated</span> axion isocurvature perturbations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kadota, Kenji; Kobayashi, Tatsuo; Otsuka, Hajime</p> <p>2016-01-25</p> <p>We study the inflation scenarios, in the framework of superstring theory, where the inflaton is an axion producing the adiabatic curvature perturbations while there exists another light axion producing the isocurvature perturbations. We discuss how the non-trivial couplings among string axions can generically arise, and calculate the consequent <span class="hlt">cross-correlations</span> between the adiabatic and isocurvature modes through concrete examples. Based on the Planck analysis on the generally correlated isocurvature perturbations, we show that there is a preference for the existence of the correlated isocurvature modes for the axion monodromy inflation while the natural inflation disfavors such isocurvature modes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1045175','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1045175"><span>Bunch Length Measurements With Laser/SR <span class="hlt">Cross-Correlation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Miller, Timothy; Daranciang, Dan; Lindenberg, Aaron; Corbett, Jeff; Fisher, Alan; Goodfellow, John; Huang, Xiaobiao; Mok, Walter; Safranek, James; Wen, Haidan; /SLAC</p> <p>2012-07-06</p> <p>By operating SPEAR3 in low-{alpha} mode the storage ring can generate synchrotron radiation pulses of order 1ps. Applications include pump-probe x-ray science and the production of THz radiation in the CSR regime. Measurements of the bunch length are difficult, however, because the light intensity is low and streak cameras typically provide resolution of only a few ps. Tests are now underway to resolve the short bunch length using <span class="hlt">cross-correlation</span> between a 60-fs Ti:Sapphire laser and the visible SR beam in a BBO crystal. In this paper we report on the experimental setup, preliminary measurements and prospects for further improvement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/865911','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/865911"><span>Acoustic <span class="hlt">cross-correlation</span> flowmeter for solid-gas flow</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Sheen, Shuh-Haw; Raptis, Apostolos C.</p> <p>1986-01-01</p> <p>Apparatus for measuring particle velocity in a solid-gas flow within a pipe includes: first and second transmitting transducers for transmitting first and second ultrasonic signals into the pipe at first and second locations, respectively, along the pipe; an acoustic decoupler, positioned between said first and second transmitting transducers, for acoustically isolating said first and second signals from one another; first and second detecting transducers for detecting said first and second signals and for generating first and second detected signals in response to said first and second detected signals; and means for <span class="hlt">cross-correlating</span> said first and second output signals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6006812','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/6006812"><span>Acoustic <span class="hlt">cross-correlation</span> flowmeter for solid-gas flow</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Sheen, S.H.; Raptis, A.C.</p> <p>1984-05-14</p> <p>Apparatus for measuring particle velocity in a solid-gas flow within a pipe includes: first and second transmitting transducers for transmitting first and second ultrasonic signals into the pipe at first and second locations, respectively, along the pipe; an acoustic decoupler, positioned between said first and second transmitting transducers, for acoustically isolating said first and second signals from one another; first and second detecting transducers for detecting said first and second signals and for generating first and second detected signals; and means for <span class="hlt">cross-correlating</span> said first and second output signals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22525047','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22525047"><span>Axion inflation with <span class="hlt">cross-correlated</span> axion isocurvature perturbations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kadota, Kenji; Kobayashi, Tatsuo; Otsuka, Hajime E-mail: kobayashi@particle.sci.hokudai.ac.jp</p> <p>2016-01-01</p> <p>We study the inflation scenarios, in the framework of superstring theory, where the inflaton is an axion producing the adiabatic curvature perturbations while there exists another light axion producing the isocurvature perturbations. We discuss how the non-trivial couplings among string axions can generically arise, and calculate the consequent <span class="hlt">cross-correlations</span> between the adiabatic and isocurvature modes through concrete examples. Based on the Planck analysis on the generally correlated isocurvature perturbations, we show that there is a preference for the existence of the correlated isocurvature modes for the axion monodromy inflation while the natural inflation disfavors such isocurvature modes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720017731','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720017731"><span>Noise elimination by piecewise <span class="hlt">cross</span> <span class="hlt">correlation</span> of photometer outputs</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Krause, F. R.; Hablutzel, B. C.</p> <p>1969-01-01</p> <p>A piecewise <span class="hlt">cross</span> <span class="hlt">correlation</span> technique has been developed to analyze the outputs of remote detection devices. The purpose of this technique is to eliminate the noise from optical background fluctuations, from transmission fluctuations and from detectors by calculating the instantaneous product of the detector output and a reference signal. Each noise component causes positive and negative oscillations of the instantaneous product and may thus be cancelled by an integration of the instantaneous product. The resultant product mean values will then contain the desired information on the spatial and temporal variation of emission, absorption and scattering processes in the atmosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..468..839X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..468..839X"><span>The application of the multifractal <span class="hlt">cross-correlation</span> analysis methods in radar target detection within sea clutter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xi, Caiping; Zhang, Shuning; Xiong, Gang; Zhao, Huichang; Yang, Yonghong</p> <p>2017-02-01</p> <p>Many complex systems generate multifractal time series which are long-range <span class="hlt">cross-correlated</span>. This paper introduces three multifractal <span class="hlt">cross-correlation</span> analysis methods, such as multifractal <span class="hlt">cross-correlation</span> analysis based on the partition <span class="hlt">function</span> approach (MFXPF), multifractal detrended <span class="hlt">cross-correlation</span> analysis (MFDCCA) methods based on detrended fluctuation analysis (MFXDFA) and detrended moving average analysis (MFXDMA), which only consider one moment order. We do comparative analysis of the artificial time series (binomial multiplicative cascades and Cantor sets with different probabilities) by these methods. Then we do a feasibility test of the fixed threshold target detection within sea clutter by applying the multifractal <span class="hlt">cross-correlation</span> analysis methods to the IPIX radar sea clutter data. The results show that it is feasible to use the method of the fixed threshold based on the multifractal feature parameter Δf(α) by the MFXPF and MFXDFA-1 methods. At last, we give the main conclusions and provide a valuable reference on how to choose the multifractal algorithms, the detection parameters and the target detection methods within sea clutter in practice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EL....11248001R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EL....11248001R"><span>Detrended <span class="hlt">cross-correlations</span> between returns, volatility, trading activity, and volume traded for the stock market companies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rak, Rafał; Drożdż, Stanisław; Kwapień, Jarosław; Oświȩcimka, Paweł</p> <p>2015-11-01</p> <p>We consider a few quantities that characterize trading on a stock market in a fixed time interval: logarithmic returns, volatility, trading activity (i.e., the number of transactions), and volume traded. We search for the power-law <span class="hlt">cross-correlations</span> among these quantities aggregated over different time units from 1 min to 10 min. Our study is based on empirical data from the American stock market consisting of tick-by-tick recordings of 31 stocks listed in Dow Jones Industrial Average during the years 2008-2011. Since all the considered quantities except the returns show strong daily patterns related to the variable trading activity in different parts of a day, which are the most evident in the autocorrelation <span class="hlt">function</span>, we remove these patterns by detrending before we proceed further with our study. We apply the multifractal detrended <span class="hlt">cross-correlation</span> analysis with sign preserving (MFCCA) and show that the strongest power-law <span class="hlt">cross-correlations</span> exist between trading activity and volume traded, while the weakest ones exist (or even do not exist) between the returns and the remaining quantities. We also show that the strongest <span class="hlt">cross-correlations</span> are carried by those parts of the signals that are characterized by large and medium variance. Our observation that the most convincing power-law <span class="hlt">cross-correlations</span> occur between trading activity and volume traded reveals the existence of strong fractal-like coupling between these quantities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.9362H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.9362H"><span>Crustal tomography of the Aegean-Anatolian domain using noise <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hubans, Fabien; Paul, Anne; Campillo, Michel; Karabulut, Hayrullah; Hatzidimitriou, Panagiotis</p> <p>2010-05-01</p> <p>Data of more than 150 temporary and permanent broadband seismological stations deployed in the Aegean-Anatolian domain between May 2007 and May 2009 are grouped in the SIMBAAD (Seismic Imaging of the Mantle Across the Anatolian Domain) dataset. We compute noise <span class="hlt">cross-correlations</span> between all station pairs on a 1.5-yr duration. We obtain more than 11.000 correlations for each component of the <span class="hlt">cross-correlation</span> tensor. We apply a MFA (Multiple Filter Analysis) method to measure group velocity dispersion curves of Rayleigh waves on 4 components of the correlation tensor (ZZ, ZR, RZ, RR) and of Love waves on the TT component, both in positive and negative times. According to the theory, a noise <span class="hlt">cross-correlation</span> converges to the Green <span class="hlt">function</span> if noise sources are randomly distributed around the station pair. If this condition is fulfilled, the <span class="hlt">cross-correlation</span> should be symmetrical in time. We compare group velocity measurements between positive and negative times to evaluate the convergence of each <span class="hlt">cross-correlation</span> to the Green <span class="hlt">function</span>. The quality of the symmetry is used to weight the time measurements in the inversion for group velocity maps. In the last step, Rayleigh wave group velocity data are inverted for a 3-D model of S-wave velocity. This processing gives an image of the crustal structure in the area [37-41°N ; 23-33°E] with a horizontal resolution of 60 to 200 km depending on depth and station coverage. The shallowest layers clearly display the present-day thick sedimentary basins (Axios, Thrace, Marmara, Bay of Antalya, ...) and older sedimentary nappes (Lycian nappes, Miocene sediments in the Kirsehir block) as strong low velocity anomalies. At larger depth, Southwestern Anatolia is characterized by a broad low velocity anomaly which contrasts with the higher velocities of the Aegean Sea. We clearly image a West to East increase of Moho depth from 20-25 km in the Aegean Sea to 35 km in the Anatolian plateau. This increase located between 27°E and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28380842','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28380842"><span>General spatial phase-shifting interferometry by optimizing the signal <span class="hlt">retrieving</span> <span class="hlt">function</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Yi; Qiu, Xiang; Xiong, Jiaxiang; Li, Bingbo; Zhong, Liyun; Liu, Shengde; Zhou, Yunfei; Tian, Jindong; Lu, Xiaoxu</p> <p>2017-04-03</p> <p>A general spatial phase-shifting (GSPS) interferometry method is proposed to achieve phase <span class="hlt">retrieval</span> from one-frame spatial carrier frequency interferogram. By optimizing the internal signal <span class="hlt">retrieving</span> <span class="hlt">function</span> of the spatial phase-shifting (SPS) method, the accuracy, anti-noise ability and speed of phase <span class="hlt">retrieval</span> can be significantly improved, meanwhile the corresponding local calculation property is reserved. Especially, in the case that the ratio of the spatial carrier to the phase variation rate are small, the proposed method reveals obvious advantage in the accuracy improvement relative to the conventional SPS methods, so the more details of measured sample can be effectively reserved through introducing smaller spatial carrier frequency, and this will facilitate its application in interference microscopy. The principle analysis, numerical simulation and experimental result are employed to verify the performance of the proposed GSPS method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1346357-cross-correlating-galaxy-surveys','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1346357-cross-correlating-galaxy-surveys"><span><span class="hlt">Cross-correlating</span> 2D and 3D galaxy surveys</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Passaglia, Samuel; Manzotti, Alessandro; Dodelson, Scott</p> <p>2017-06-08</p> <p>Galaxy surveys probe both structure formation and the expansion rate, making them promising avenues for understanding the dark universe. Photometric surveys accurately map the 2D distribution of galaxy positions and shapes in a given redshift range, while spectroscopic surveys provide sparser 3D maps of the galaxy distribution. We present a way to analyse overlapping 2D and 3D maps jointly and without loss of information. We represent 3D maps using spherical Fourier-Bessel (sFB) modes, which preserve radial coverage while accounting for the spherical sky geometry, and we decompose 2D maps in a spherical harmonic basis. In these bases, a simple expression exists for the <span class="hlt">cross-correlation</span> of the two fields. One very powerful application is the ability to simultaneously constrain the redshift distribution of the photometric sample, the sample biases, and cosmological parameters. We use our framework to show that combined analysis of DESI and LSST can improve cosmological constraints by factors ofmore » $${\\sim}1.2$$ to $${\\sim}1.8$$ on the region where they overlap relative to identically sized disjoint regions. We also show that in the overlap of DES and SDSS-III in Stripe 82, <span class="hlt">cross-correlating</span> improves photo-$z$ parameter constraints by factors of $${\\sim}2$$ to $${\\sim}12$$ over internal photo-$z$ reconstructions.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009PhyA..388..705C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009PhyA..388..705C"><span><span class="hlt">Cross-correlation</span> dynamics in financial time series</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Conlon, T.; Ruskin, H. J.; Crane, M.</p> <p>2009-03-01</p> <p>The dynamics of the equal-time <span class="hlt">cross-correlation</span> matrix of multivariate financial time series is explored by examination of the eigenvalue spectrum over sliding time windows. Empirical results for the S&P 500 and the Dow Jones Euro Stoxx 50 indices reveal that the dynamics of the small eigenvalues of the <span class="hlt">cross-correlation</span> matrix, over these time windows, oppose those of the largest eigenvalue. This behaviour is shown to be independent of the size of the time window and the number of stocks examined. A basic one-factor model is then proposed, which captures the main dynamical features of the eigenvalue spectrum of the empirical data. Through the addition of perturbations to the one-factor model, (leading to a ‘market plus sectors’ model), additional sectoral features are added, resulting in an Inverse Participation Ratio comparable to that found for empirical data. By partitioning the eigenvalue time series, we then show that negative index returns, ( drawdowns), are associated with periods where the largest eigenvalue is greatest, while positive index returns, ( drawups), are associated with periods where the largest eigenvalue is smallest. The study of correlation dynamics provides some insight on the collective behaviour of traders with varying strategies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1366709','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1366709"><span>Cross Talk Free Fluorescence <span class="hlt">Cross</span> <span class="hlt">Correlation</span> Spectroscopy in Live Cells</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Thews, Elmar; Gerken, Margarita; Eckert, Reiner; Zäpfel, Johannes; Tietz, Carsten; Wrachtrup, Jörg</p> <p>2005-01-01</p> <p>Fluorescence correlation spectroscopy (FCS) is now a widely used technique to measure small ensembles of labeled biomolecules with single molecule detection sensitivity (e.g., low endogenous concentrations). Fluorescence <span class="hlt">cross</span> <span class="hlt">correlation</span> spectroscopy (FCCS) is a derivative of this technique that detects the synchronous movement of two biomolecules with different fluorescence labels. Both methods can be applied to live cells and, therefore, can be used to address a variety of unsolved questions in cell biology. Applications of FCCS with autofluorescent proteins (AFPs) have been hampered so far by cross talk between the detector channels due to the large spectral overlap of the fluorophores. Here we present a new method that combines advantages of these techniques to analyze binding behavior of proteins in live cells. To achieve this, we have used dual color excitation of a common pair of AFPs, ECFP and EYFP, being discriminated in excitation rather than in emission. This is made possible by pulsed excitation and detection on a shorter timescale compared to the average residence time of particles in the FCS volume element. By this technique we were able to eliminate cross talk in the detector channels and obtain an undisturbed <span class="hlt">cross</span> <span class="hlt">correlation</span> signal. The setup was tested with ECFP/EYFP lysates as well as chimeras as negative and positive controls and demonstrated to work in live HeLa cells coexpressing the two fusion proteins ECFP-connexin and EYFP-connexin. PMID:15951373</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15447548','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15447548"><span>Random matrix theory analysis of <span class="hlt">cross</span> <span class="hlt">correlations</span> in financial markets.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Utsugi, Akihiko; Ino, Kazusumi; Oshikawa, Masaki</p> <p>2004-08-01</p> <p>We confirm universal behaviors such as eigenvalue distribution and spacings predicted by random matrix theory (RMT) for the <span class="hlt">cross</span> <span class="hlt">correlation</span> matrix of the daily stock prices of Tokyo Stock Exchange from 1993 to 2001, which have been reported for New York Stock Exchange in previous studies. It is shown that the random part of the eigenvalue distribution of the <span class="hlt">cross</span> <span class="hlt">correlation</span> matrix is stable even when deterministic correlations are present. Some deviations in the small eigenvalue statistics outside the bounds of the universality class of RMT are not completely explained with the deterministic correlations as proposed in previous studies. We study the effect of randomness on deterministic correlations and find that randomness causes a repulsion between deterministic eigenvalues and the random eigenvalues. This is interpreted as a reminiscent of "level repulsion" in RMT and explains some deviations from the previous studies observed in the market data. We also study correlated groups of issues in these markets and propose a refined method to identify correlated groups based on RMT. Some characteristic differences between properties of Tokyo Stock Exchange and New York Stock Exchange are found.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009PhyA..388.3851L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009PhyA..388.3851L"><span>Structure of a financial <span class="hlt">cross-correlation</span> matrix under attack</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lim, Gyuchang; Kim, SooYong; Kim, Junghwan; Kim, Pyungsoo; Kang, Yoonjong; Park, Sanghoon; Park, Inho; Park, Sang-Bum; Kim, Kyungsik</p> <p>2009-09-01</p> <p>We investigate the structure of a perturbed stock market in terms of correlation matrices. For the purpose of perturbing a stock market, two distinct methods are used, namely local and global perturbation. The former involves replacing a correlation coefficient of the <span class="hlt">cross-correlation</span> matrix with one calculated from two Gaussian-distributed time series while the latter reconstructs the <span class="hlt">cross-correlation</span> matrix just after replacing the original return series with Gaussian-distributed time series. Concerning the local case, it is a technical study only and there is no attempt to model reality. The term ‘global’ means the overall effect of the replacement on other untouched returns. Through statistical analyses such as random matrix theory (RMT), network theory, and the correlation coefficient distributions, we show that the global structure of a stock market is vulnerable to perturbation. However, apart from in the analysis of inverse participation ratios (IPRs), the vulnerability becomes dull under a small-scale perturbation. This means that these analysis tools are inappropriate for monitoring the whole stock market due to the low sensitivity of a stock market to a small-scale perturbation. In contrast, when going down to the structure of business sectors, we confirm that correlation-based business sectors are regrouped in terms of IPRs. This result gives a clue about monitoring the effect of hidden intentions, which are revealed via portfolios taken mostly by large investors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvD..95l3508P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvD..95l3508P"><span><span class="hlt">Cross-correlating</span> 2D and 3D galaxy surveys</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Passaglia, Samuel; Manzotti, Alessandro; Dodelson, Scott</p> <p>2017-06-01</p> <p>Galaxy surveys probe both structure formation and the expansion rate, making them promising avenues for understanding the dark universe. Photometric surveys accurately map the 2D distribution of galaxy positions and shapes in a given redshift range, while spectroscopic surveys provide sparser 3D maps of the galaxy distribution. We present a way to analyse overlapping 2D and 3D maps jointly and without loss of information. We represent 3D maps using spherical Fourier-Bessel (sFB) modes, which preserve radial coverage while accounting for the spherical sky geometry, and we decompose 2D maps in a spherical harmonic basis. In these bases, a simple expression exists for the <span class="hlt">cross-correlation</span> of the two fields. One very powerful application is the ability to simultaneously constrain the redshift distribution of the photometric sample, the sample biases, and cosmological parameters. We use our framework to show that combined analysis of DESI and LSST can improve cosmological constraints by factors of ˜1.2 to ˜1.8 on the region where they overlap relative to identically sized disjoint regions. We also show that in the overlap of DES and SDSS-III in Stripe 82, <span class="hlt">cross-correlating</span> improves photo-z parameter constraints by factors of ˜2 to ˜12 over internal photo-z reconstructions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3695882','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3695882"><span>Episodic memory <span class="hlt">retrieval</span> for story characters in high-<span class="hlt">functioning</span> autism</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2013-01-01</p> <p>Background The objective of this study was to examine differences in episodic memory <span class="hlt">retrieval</span> between individuals with autism spectrum disorder (ASD) and typically developing (TD) individuals. Previous studies have shown that personality similarities between readers and characters facilitated reading comprehension. Highly extraverted participants read stories featuring extraverted protagonists more easily and judged the outcomes of such stories more rapidly than did less extraverted participants. Similarly, highly neurotic participants judged the outcomes of stories with neurotic protagonists more rapidly than did participants with low levels of neuroticism. However, the impact of the similarity effect on memory <span class="hlt">retrieval</span> remains unclear. This study tested our ‘similarity hypothesis’, namely that memory <span class="hlt">retrieval</span> is enhanced when readers with ASD and TD readers read stories featuring protagonists with ASD and with characteristics associated with TD individuals, respectively. Methods Eighteen Japanese individuals (one female) with high-<span class="hlt">functioning</span> ASD (aged 17 to 40 years) and 17 age- and intelligence quotient (IQ)-matched Japanese (one female) TD participants (aged 22 to 40 years) read 24 stories; 12 stories featured protagonists with ASD characteristics, and the other 12 featured TD protagonists. Participants read a single sentence at a time and pressed a spacebar to advance to the next sentence. After reading all 24 stories, they were asked to complete a recognition task about the target sentence in each story. Results To investigate episodic memory in ASD, we analyzed encoding based on the reading times for and readability of the stories and <span class="hlt">retrieval</span> processes based on the accuracy of and response times for sentence recognition. Although the results showed no differences between ASD and TD groups in encoding processes, they did reveal inter-group differences in memory <span class="hlt">retrieval</span>. Although individuals with ASD demonstrated the same level of accuracy as did</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1357203-cross-correlation-study-fermi-lat-ray-diffuse-extragalactic-signal','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1357203-cross-correlation-study-fermi-lat-ray-diffuse-extragalactic-signal"><span>A <span class="hlt">cross-correlation</span> study of the Fermi-LAT γ-ray diffuse extragalactic signal</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Xia, Jun -Qing; Cuoco, Alessandro; Branchini, Enzo; ...</p> <p>2011-09-12</p> <p>In this work, starting from 21 months of data from the Fermi Large Area Telescope (LAT), we derive maps of the residual isotropic γ-ray emission, a relevant fraction of which is expected to be contributed by the extragalactic diffuse γ-ray background (EGB). We search for the auto-correlation signals in the above γ-ray maps and for the <span class="hlt">cross-correlation</span> signal with the angular distribution of different classes of objects that trace the large-scale structure of the Universe. We compute the angular two-point auto-correlation <span class="hlt">function</span> of the residual Fermi-LAT maps at energies E > 1 GeV, E > 3 GeV and E >more » 30 GeV well above the Galactic plane and find no significant correlation signal. This is, indeed, what is expected if the EGB were contributed by BL Lacertae (BLLacs), Flat Spectrum Radio Quasars (FSRQs) or star-forming galaxies, since, in this case, the predicted signal is very weak. Then, we search for the Integrated Sachs–Wolfe (ISW) signature by <span class="hlt">cross-correlating</span> the Fermi-LAT maps with the 7-year Wilkinson Microwave Anisotropy Probe (WMAP7) cosmic microwave background map. We find a <span class="hlt">cross-correlation</span> consistent with zero, even though the expected signal is larger than that of the EGB auto-correlation. Lastly, in an attempt to constrain the nature of the γ-ray background, we <span class="hlt">cross-correlate</span> the Fermi-LAT maps with the angular distributions of objects that may contribute to the EGB: quasi-stellar objects (QSOs) in the Sloan Digital Sky Survey Data Release 6 (SDSS-DR6) catalogue, NRAO VLA Sky Survey (NVSS) galaxies, Two Micron All Sky Survey (2MASS) galaxies and Luminous Red Galaxies (LRGs) in the SDSS catalogue. The <span class="hlt">cross-correlation</span> is always consistent with zero, in agreement with theoretical expectations, but we find (with low statistical significance) some interesting features that may indicate that some specific classes of objects contribute to the EGB. A χ2 analysis confirms that the correlation properties of the 21-month data do not provide</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..453..278R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..453..278R"><span><span class="hlt">Cross-correlations</span> between Baltic Dry Index and crude oil prices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruan, Qingsong; Wang, Yao; Lu, Xinsheng; Qin, Jing</p> <p>2016-07-01</p> <p>This paper examines the <span class="hlt">cross-correlation</span> properties of Baltic Dry Index (BDI) and crude oil prices using <span class="hlt">cross-correlation</span> statistics test and multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA). The empirical results show that the <span class="hlt">cross-correlations</span> between BDI and crude oil prices are significantly multifractal. By introducing the concept of a "crossover", we find that the <span class="hlt">cross-correlations</span> are strongly persistent in the short term and weakly anti-persistent in the long term. Moreover, <span class="hlt">cross-correlations</span> of all kinds of fluctuations are persistent in the short time while <span class="hlt">cross-correlations</span> of small fluctuations are persistent and those of large fluctuations are anti-persistent in the long term. We have also verified that the multifractality of the <span class="hlt">cross-correlations</span> of BDI and crude oil prices is both attributable to the persistence of fluctuations of time series and fat-tailed distributions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..463..188D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..463..188D"><span>Multifractal detrended <span class="hlt">Cross</span> <span class="hlt">Correlation</span> Analysis of Foreign Exchange and SENSEX fluctuation in Indian perspective</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dutta, Srimonti; Ghosh, Dipak; Chatterjee, Sucharita</p> <p>2016-12-01</p> <p>The manuscript studies autocorrelation and <span class="hlt">cross</span> <span class="hlt">correlation</span> of SENSEX fluctuations and Forex Exchange Rate in respect to Indian scenario. Multifractal detrended fluctuation analysis (MFDFA) and multifractal detrended <span class="hlt">cross</span> <span class="hlt">correlation</span> analysis (MFDXA) were employed to study the correlation between the two series. It was observed that the two series are strongly <span class="hlt">cross</span> <span class="hlt">correlated</span>. The change of degree of <span class="hlt">cross</span> <span class="hlt">correlation</span> with time was studied and the results are interpreted qualitatively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.7208B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.7208B"><span>Using waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> for automatic recovery of aftershock sequences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bobrov, Dmitry; Kitov, Ivan; Rozhkov, Mikhail</p> <p>2017-04-01</p> <p>Aftershock sequences of the largest earthquakes are difficult to recover. There can be several hundred mid-sized aftershocks per hour within a few hundred km from each other recorded by the same stations. Moreover, these events generate thousands of reflected/refracted phases having azimuth and slowness close to those from the P-waves. Therefore, aftershock sequences with thousands of events represent a major challenge for automatic and interactive processing at the International Data Centre (IDC) of the Comprehensive Nuclear-Test-Ban Organization (CTBTO). Standard methods of detection and phase association do not use all information contained in signals. As a result, wrong association of the first and later phases, both regular and site specific, produces enormous number of wrong event hypotheses and destroys valid event hypotheses in automatic IDC processing. In turn, the IDC analysts have to reject false and recreate valid hypotheses wasting precious human resources. At the current level of the IDC catalogue completeness, the method of waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> (WCC) can resolve most of detection and association problems fully utilizing the similarity of waveforms generated by aftershocks. Array seismic stations of the International monitoring system (IMS) can enhance the performance of the WCC method: reduce station-specific detection thresholds, allow accurate estimate of signal attributes, including relative magnitude, and effectively suppress irrelevant arrivals. We have developed and tested a prototype of an aftershock tool matching all IDC processing requirements and merged it with the current IDC pipeline. This tool includes creation of master events consisting of real or synthetic waveform templates at ten and more IMS stations; <span class="hlt">cross</span> <span class="hlt">correlation</span> (CC) of real-time waveforms with these templates, association of arrivals detected at CC-traces in event hypotheses; building events matching the IDC quality criteria; and resolution of conflicts between events</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6074372','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6074372"><span><span class="hlt">Cross-correlated</span> photon scattering during the photocycle of bacteriorhodopsin</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Czege, J.; Reinisch, L. )</p> <p>1990-09-01</p> <p>Changes in the ultraviolet light scattering from a suspension of purple membrane fragments were detected during the photocycle of bacteriorhodopsin with a <span class="hlt">cross-correlation</span> method. The scattered light intensity from a suspension of membrane fragments containing the protein bacteriorhodopsin was measured on a logarithmic time scale of 1 microsecond to 0.1 s at pH 4.6 after the photocycle was initiated with a polarized 532-nm laser flash. A simple model of curved sheets with positive and negative changes in the curvature is used to describe the observed light scattering changes. A detailed mathematical derivation of the model as well as the pictorial description are given. The changes in curvature of the membrane fragment are more than likely driven by the protein during the photocycle and are observed to have at least two time-resolved components, each changing the curvature of the fragment with an opposite sign.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AIPC.1201...37F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AIPC.1201...37F"><span>Investigation Of The Diffuse IGM By <span class="hlt">Cross-Correlation</span> Studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farnsworth, Damon; Brown, Shea; Rudnick, Lawrence</p> <p>2009-12-01</p> <p>We present results from the first <span class="hlt">cross-correlation</span> search for the synchrotron component of the diffuse intergalactic medium (IGM) in filamentary large scale structure (LSS). We used the low resolution (36') Bonn survey at 21cm, with the infrared 2MASS catalog as a tracer of the LSS. Synchrotron emission likely results from LSS formation shocks and feedback from AGN and galactic winds [2]. We determined 3σ upper limits to the diffuse emission in units of flux per galaxy; these correspond to filament equipartition magnetic fields as low as 0.2 μG. The detection threshold for the average (peak) filament brightness is 1 (7) mK for 0.03<z<0.04, far below the 50 mK effective sensitivity of the Bonn survey, demonstrating the power of this technique.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AIPC.1487..207Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AIPC.1487..207Z"><span><span class="hlt">Cross</span> <span class="hlt">correlation</span> method application to prompt fission neutron investigation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zeynalova, O. V.; Zeynalov, Sh.; Nazarenko, M. A.; Hambsch, F.-J.; Oberstedt, S.</p> <p>2012-10-01</p> <p>Do The prompt neutron emission in spontaneous fission of 252Cf has been investigated applying <span class="hlt">cross</span> <span class="hlt">correlation</span> method and digital signal processing algorithms. A new mathematical approach for neutron/gamma pulse shape separation was developed and implemented for prompt fission neutron (PFN) time-of-flight measurement. The main goal was development of automated data analysis algorithms and procedures for data analysis with minimum human intervention. Experimental data was taken with a twin Frisch-grid ionization chamber and a NE213-equivalent neutron detector in an experimental setup similar to well work of C. Budtz-Jorgensen and H.-H. Knitter [1]. About 2*107 fission events were registered with 2*105 neutron/gamma detection in coincidence with fission fragments. Fission fragment kinetic energy, mass and angular distribution, neutron time-of-flight and pulse shape have been investigated using a 12 bit waveform digitizer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA092523','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA092523"><span>Effects of <span class="hlt">Cross-Correlation</span> Interference on an Optical Code Division Multiple Access Communication System.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1980-01-01</p> <p>noise and <span class="hlt">cross-correlation</span> interference. Numerical results are given for both severe and moderate lognormal fading, using the Nakagami m -distribution...form of the Q -<span class="hlt">function</span> [Schwartz, M ., 1966) to approximate the error probability. For the case where U1 = U 2 U . K = U the error probability is...30 0 L.- 0 0 L 0 M -1 W) L C L. /)4-) .- I C 0 0 3 L ( C. )L L (I) 4 _ to0 CC :O .0 6L. O W > 0 a) C 0 C* 0 II CI .0 ~ 4L 0. to I Q ’.0. -It Q a) 0 3 06</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12241255','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12241255"><span>Time-dependent <span class="hlt">cross-correlations</span> between different stock returns: a directed network of influence.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kullmann, L; Kertész, J; Kaski, K</p> <p>2002-08-01</p> <p>We study the time-dependent <span class="hlt">cross-correlations</span> of stock returns, i.e., we measure the correlation as the <span class="hlt">function</span> of the time shift between pairs of stock return time series using tick-by-tick data. We find a weak but significant effect showing that in many cases the maximum correlation appears at nonzero time shift, indicating directions of influence between the companies. Due to the weakness of this effect and the shortness of the characteristic time (of the order of a few minutes), our findings are compatible with market efficiency. The interaction of companies defines a directed network of influence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930084452','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930084452"><span>Near Noise Field of a Jet-engine Exhaust II : <span class="hlt">Cross</span> <span class="hlt">Correlation</span> of Sound Pressures</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Callaghan, Edmund E; Howes, Walton L; Coles, Willard D</p> <p>1956-01-01</p> <p>Pressure <span class="hlt">cross</span> <span class="hlt">correlations</span> were obtained over a range of jet velocities both longitudinally and laterally for the overall sound pressure and for several frequency bands. The region of positive correlation was found to increase with distance downstream of the nozzle exit and was greater for lateral than for longitudinal correlations. In general, little change in the correlation curves was found as a <span class="hlt">function</span> of jet velocity or frequency band width. Measurements made with a fixed and a movable microphone in a plate showed correlations similar to the free-field results. The results are interpreted in terms of pressure loads on surfaces.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110012874','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110012874"><span>Effect of <span class="hlt">Cross-Correlation</span> on Geomagnetic Forecast Accuracies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kuang, Weijia; Wei, Zigang; Tangborn, Andrew</p> <p>2011-01-01</p> <p>Surface geomagnetic observation can determine up to degree L = 14 time-varying spherical harmonic coefficients of the poloidal magnetic field. Assimilation of these coefficients to numerical dynamo simulation could help us understand better the dynamical processes in the Earth's outer core, and to provide more accurate forecast of geomagnetic secular variations (SV). In our previous assimilation studies, only the poloidal magnetic field in the core is corrected by the observations in the analysis. Unobservable core state variables (the toroidal magnetic field and the core velocity field) are corrected via the dynamical equations of the geodynamo. Our assimilation experiments show that the assimilated core state converges near the CMB, implying that the dynamo state is strongly constrained by surface geomagnetic observations, and is pulled closer to the truth by the data. We are now carrying out an ensemble of assimilation runs with 1000 years of geomagnetic and archeo/paleo magnetic record. In these runs the <span class="hlt">cross</span> <span class="hlt">correlation</span> between the toroidal and the poloidal magnetic fields is incorporated into the analysis. This correlation is derived from the physical boundary conditions of the toroidal field at the core-mantle boundary (CMB). The assimilation results are then compared with those of the ensemble runs without the <span class="hlt">cross-correlation</span>, aiming at understanding two fundamental issues: the effect of the crosscorrelation on (1) the convergence of the core state, and (2) the SV prediction accuracies. The constrained dynamo solutions will provide valuable insights on interpreting the observed SV, e.g. the near-equator magnetic flux patches, the core-mantle interactions, and possibly other geodynamic observables.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S13B2565W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S13B2565W"><span>Wavelet-based group and phase velocity measurements: application to ambient noise <span class="hlt">cross</span> <span class="hlt">correlation</span> observations from OBS survey offshore Taiwan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, W. W.; Yang, H. Y.; Hung, S. H.; Kuo, B. Y.</p> <p>2016-12-01</p> <p>In recent years, empirical Green's <span class="hlt">functions</span> (EGFs) reconstructed from ambient noise <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> (NCFs) between paired stations provide the unprecedented interstation path coverage within highly instrumented regions for high-resolution tomographic imaging. Dispersion analysis of the <span class="hlt">retrieved</span> signals including multimode surface waves and body waves often excited by highly nonstationary noise sources becomes a routine but essential task. Since 2008, a number of broadband OBS experiments from the Institute of Earth Sciences (IES), Academia Sinica of Taiwan and TAIGER, a US-Taiwan cooperative research project, have been conducted in deep sea east of Taiwan. In this study, we use continuous recordings of vertical displacements and differential pressure gauges in 36 broadband OBSs deployed offshore eastern Taiwan to investigate the subseafloor structures from extracted Rayleigh waves and the source origin contributing to the generation of very long-period infragravity waves. We apply a wavelet-based method to characterize the time-varying spectral properties and measure the frequency-dependent group and phase velocities of these waves. The results show fundamental mode Rayleigh waves in both the displacement and DPG derived NCFs with a dominant period of 3-5 s and relatively slow speed of 0.5-1.0 km/s, while the other group of earlier dispersive arrivals predominant at 1-3 s, likely associated with higher mode surface waves or body waves, only emerges in the DPG derived NCFs propagates at a much faster speed of 1.5-3 km/s. The infragravity waves at periods ranging from 50 to 160 s found in DPGs records show the speed of 0.05-0.1 km/s. With these robust dispersion measurements, we will conduct the Bayesian inversion to constrain the radial velocity structures beneath the seafloor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S13B2560R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S13B2560R"><span><span class="hlt">Retrieval</span> and Validation of Reflections from Ambient Noise Green's <span class="hlt">Functions</span> Using Synthetic Ground Motions and Active Source Experiment Results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rábade, S.; Ramirez-Guzmán, L.; Juarez, A.; Aguirre, J.; Avila-Carrera, R.</p> <p>2016-12-01</p> <p>Researchers have successfully used ambient noise correlation techniques at global, regional, and local scales to extract information of the subsurface but few analyses attempt to validate the Green's <span class="hlt">function</span> obtained. Recently, a dense array of three-component 10Hz geophones was deployed in northern Mexico for six hours, with the intention of analyzing the capabilities of these networks in the mapping of natural resources. We obtained Green's <span class="hlt">functions</span> using ambient noise <span class="hlt">cross-correlations</span> and then we compare them against synthetic seismograms obtained using FEM with a velocity model built using the reflectors and P-wave velocities reported from the active source experiments. S-wave velocities are constrained using values from several ambient noise techniques, such as SPAC, H/V, and seismic tomography. Preliminary results show that the Green's <span class="hlt">functions</span> obtained with ambient noise techniques are similar to the synthetics from the 3D active model. As in many cases, surface waves dominate the ambient noise Green's <span class="hlt">functions</span>, but in lower frequencies (1-5 Hz) body waves are more energetic. After the analysis, we apply traditional seismic reflection techniques and obtain similar results to the 3D model used for validation purposes. These results show that it is possible to use reflection techniques with Green's <span class="hlt">function</span> obtained using ambient noise <span class="hlt">cross-correlations</span>, enabling the exploration of sites where actives sources are not feasible. We can also evaluate the limitation of ambient noise Green's <span class="hlt">functions</span> to plan better future array deployments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.6805L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.6805L"><span>Imaging of a deep geothermal reservoir using ambient noise <span class="hlt">cross</span> <span class="hlt">correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lehujeur, Maximilien; Vergne, Jérôme; Maggi, Alessia; Schmittbuhl, Jean</p> <p>2013-04-01</p> <p>The ambient noise <span class="hlt">cross</span> <span class="hlt">correlation</span> technique is a method which was initiated about 20 years ago in helioseismology. It was demonstrated that <span class="hlt">cross-correlating</span> Sun's surface motion recorded at two distinct points could lead to an estimation of the medium properties in-between the recording points. Nowadays this method is widely used in seismology and many applications can be found in the literature. This method allows determining the Green's <span class="hlt">function</span> between a pair of receivers only by correlating sufficiently long noise records. Thanks to this, it is now possible to perform tomographic studies without any deterministic sources. Nowadays, this method is widely applied at regional and continental scales using coherent seismic noise at periods larger than ˜5s. In contrary, few applications of this method have been performed at a more local scale and at periods lower than 5s, where the seismic noise is mostly dominated by anthropogenic sources. This represents the context of our study in the area of Soultz-sous-forêts and the closeby region of Rittershoffen (North-East of France) where a geothermal plant is about to be installed (ECOGI project). The aim of this study is to build an image of the geothermal reservoir using ambient noise <span class="hlt">cross-correlation</span> in a high frequency range (0.2 to 5 Hz) and to develop tools in order to follow the evolution of the reservoir during the production period. Indeed, some studies have shown that a small perturbation of the medium results in a stretching of the correlation <span class="hlt">functions</span>. Therefore computing the correlations over the time and determining the stretching coefficients allows conducting 4D tomography. We applied the ambient noise <span class="hlt">cross-correlation</span> technique using about 3 years of continuous data recorded by short-period permanent stations in this region. Various classical processing schemes have been tested. At periods lower than 0.5s, the dispersion curves are poorly constrained and the correlation <span class="hlt">functions</span> are less stable</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A34B..05S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A34B..05S"><span>Deriving the instrument transfer <span class="hlt">function</span> from OMI solar observations and its implications for trace gas <span class="hlt">retrievals</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, K.; Liu, X.; Gonzalez Abad, G.; Cai, Z.; Yang, K.; Chance, K.</p> <p>2016-12-01</p> <p>The accurate characterization of instrument transfer <span class="hlt">function</span> (ITF) is essential for the spectral calibration of space-borne grating spectrometers and the <span class="hlt">retrieval</span> of the Earth's atmospheric constituents. For OMI, the ITF is complicated <span class="hlt">functions</span> of both wavelength (the column dimension) and cross-track viewing direction (the row dimension). Preflight measurements, parameterized as hybrid Gaussian <span class="hlt">functions</span>, have been used as static inputs in spectral calibration and trace gas <span class="hlt">retrievals</span>. However, the launching process and the thermal/radiative contrast between the space and laboratory conditions may induce subtle changes in the ITF. The on-orbit thermal variation, instrument degradation, and switching of observation modes may also cause ITF variations. This study utilizes the frequent solar measurements from OMI and the recent development of high-resolution, high-accuracy reference solar spectrum to characterize the on-orbit behavior of the ITF. The ITF is fitted using various forms of analytical <span class="hlt">functions</span> or variants of the preflight ITF. The cross-track dependence of OMI ITF is significantly different from the preflight measurements. The full width at half maximum (FWHM) of detector pixels at large viewing angles are up to 10% higher than the preflight ITF FWHM. Nonetheless, the OMI ITF is stable over time (more than 10 years of operation), despite of the decaying of detector SNR and the occurrence of OMI row anomaly. Impact of the updated ITF on the <span class="hlt">retrievals</span> of trace gases (ozone, formaldehyde, etc.) will be discussed. These results have implications for future satellites targeting both short-lived species in the UV/visible and long-lived species in the infrared. The on-orbit behavior of ITF must be carefully investigated, especially for <span class="hlt">retrievals</span> with high accuracy requirements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..393..460C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..393..460C"><span>Detrended <span class="hlt">cross-correlation</span> analysis approach for assessing asymmetric multifractal detrended <span class="hlt">cross-correlations</span> and their application to the Chinese financial market</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cao, Guangxi; Cao, Jie; Xu, Longbing; He, LingYun</p> <p>2014-01-01</p> <p>We propose a new method called the multifractal asymmetric detrended <span class="hlt">cross-correlation</span> analysis method (MF-ADCCA) to investigate the asymmetric <span class="hlt">cross-correlations</span> in nonstationary time series that combine the multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA) and asymmetric detrended fluctuation analysis (A-DFA). The study aims to determine whether different scaling properties of the <span class="hlt">cross-correlations</span> are obtained if a one-time series trending is either positive or negative. We apply MF-ADCCA to analyze empirically the scaling behavior of the <span class="hlt">cross-correlations</span> among the Chinese stock market, the RMB exchange market, and the US stock market. Empirical results indicate that the <span class="hlt">cross-correlations</span> between the Chinese stock market and the RMB/USD exchange market are more persistent when any one of the markets is falling. On the contrary, the <span class="hlt">cross-correlations</span> between the Chinese stock market and the RMB/EU, RMB/GBP, RMB/JPY exchange markets and the US stock market are more persistent when one of the markets is rising. Moreover, asymmetric <span class="hlt">cross-correlations</span> between any two of the selected financial markets are multifractal.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26559474','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26559474"><span>Laterality effects in <span class="hlt">functional</span> connectivity of the angular gyrus during rest and episodic <span class="hlt">retrieval</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bellana, Buddhika; Liu, Zhongxu; Anderson, John A E; Moscovitch, Morris; Grady, Cheryl L</p> <p>2016-01-08</p> <p>The angular gyrus (AG) is consistently reported in neuroimaging studies of episodic memory <span class="hlt">retrieval</span> and is a fundamental node within the default mode network (DMN). Its specific contribution to episodic memory is debated, with some suggesting it is important for the subjective experience of episodic recollection, rather than <span class="hlt">retrieval</span> of objective episodic details. Across studies of episodic <span class="hlt">retrieval</span>, the left AG is recruited more reliably than the right. We explored <span class="hlt">functional</span> connectivity of the right and left AG with the DMN during rest and <span class="hlt">retrieval</span> to assess whether connectivity could provide insight into the nature of this laterality effect. Using data from the publically available 1000 <span class="hlt">Functional</span> Connectome Project, 8min of resting fMRI data from 180 healthy young adults were analysed. Whole-brain <span class="hlt">functional</span> connectivity at rest was measured using a seed-based Partial Least Squares (seed-PLS) approach (McIntosh and Lobaugh, 2004) with bilateral AG seeds. A subsequent analysis used 6-min of rest and 6-min of unconstrained, silent <span class="hlt">retrieval</span> of autobiographical events from a new sample of 20 younger adults. Analysis of this dataset took a more targeted approach to <span class="hlt">functional</span> connectivity analysis, consisting of univariate pairwise correlations restricted to nodes of the DMN. The seed-PLS analysis resulted in two Latent Variables that together explained ~86% of the shared cross-block covariance. The first LV revealed a common network consistent with the DMN and engaging the AG bilaterally, whereas the second LV revealed a less robust, yet significant, laterality effect in connectivity - the left AG was more strongly connected to the DMN. Univariate analyses of the second sample again revealed better connectivity between the left AG and the DMN at rest. However, during <span class="hlt">retrieval</span> the left AG was more strongly connected than the right to non-medial temporal (MTL) nodes of the DMN, and MTL nodes were more strongly connected to the right AG. The multivariate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10109441','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10109441"><span><span class="hlt">Functions</span> and requirements for subsurface barriers used in support of single-shell tank waste <span class="hlt">retrieval</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lowe, S.S.</p> <p>1993-11-16</p> <p>The mission of the Tank Waste Remediation System (TWRS) Program is to store, treat, and immobilize highly radioactive Hanford waste in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Program includes project and program activities for receiving, storing, maintaining, treating, and disposing onsite, or packaging for offsite disposal, all Hanford tank waste. Hanford tank waste includes the contents of 149 single-shell tanks (SSTs) and 28 double-shell tanks (DSTs), plus any new waste added to these facilities, and all encapsulated cesium and strontium stored onsite and returned from offsite users. A key element of the TWRS Program is <span class="hlt">retrieval</span> of the waste in the SSTs. The waste stored in these underground tanks must be removed in order to minimize environmental, safety, and health risks associated with continuing waste storage. Subsurface barriers are being considered as a means to mitigate the effects of tank leaks including those occurring during SST waste <span class="hlt">retrieval</span>. The <span class="hlt">functions</span> to be performed by subsurface barriers based on their role in <span class="hlt">retrieving</span> waste from the SSTs are described, and the requirements which constrain their application are identified. These <span class="hlt">functions</span> and requirements together define the <span class="hlt">functional</span> baseline for subsurface barriers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..416..452P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..416..452P"><span>Multifractal detrended <span class="hlt">cross-correlation</span> analysis on gold, crude oil and foreign exchange rate time series</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pal, Mayukha; Madhusudana Rao, P.; Manimaran, P.</p> <p>2014-12-01</p> <p>We apply the recently developed multifractal detrended <span class="hlt">cross-correlation</span> analysis method to investigate the <span class="hlt">cross-correlation</span> behavior and fractal nature between two non-stationary time series. We analyze the daily return price of gold, West Texas Intermediate and Brent crude oil, foreign exchange rate data, over a period of 18 years. The <span class="hlt">cross</span> <span class="hlt">correlation</span> has been measured from the Hurst scaling exponents and the singularity spectrum quantitatively. From the results, the existence of multifractal <span class="hlt">cross-correlation</span> between all of these time series is found. We also found that the <span class="hlt">cross</span> <span class="hlt">correlation</span> between gold and oil prices possess uncorrelated behavior and the remaining bivariate time series possess persistent behavior. It was observed for five bivariate series that the <span class="hlt">cross-correlation</span> exponents are less than the calculated average generalized Hurst exponents (GHE) for q<0 and greater than GHE when q>0 and for one bivariate series the <span class="hlt">cross-correlation</span> exponent is greater than GHE for all q values.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..400...20L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..400...20L"><span><span class="hlt">Cross-correlations</span> between spot and futures markets of nonferrous metals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Li; Wang, Yudong</p> <p>2014-04-01</p> <p>In this paper, we investigate <span class="hlt">cross-correlations</span> between nonferrous metal spot and futures markets using detrended <span class="hlt">cross-correlation</span> analysis (DCCA). We find the existence of significant <span class="hlt">cross-correlations</span> for both return and volatility series. The DCCA-based <span class="hlt">cross-correlation</span> coefficients are very high and decrease with the futures maturity increases. Using the multifractal extension of DCCA, the multifractality in <span class="hlt">cross-correlations</span> is revealed. We also detect the source of <span class="hlt">cross-correlations</span> between spot and futures markets. We use the vector error correction model and bivariate BEKK-GARCH to model the interactions between returns and volatilities of spot and futures, respectively. Our findings indicate that the volatility spillover between spot and futures markets contributes major to nonlinear <span class="hlt">cross-correlation</span> while the contribution of mean spillover is very minor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvD..92l3540S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvD..92l3540S"><span><span class="hlt">Cross-correlation</span> of the extragalactic gamma-ray background with luminous red galaxies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shirasaki, Masato; Horiuchi, Shunsaku; Yoshida, Naoki</p> <p>2015-12-01</p> <p>Measurements of the <span class="hlt">cross-correlation</span> between the extragalactic gamma-ray background (EGB) and large-scale structure provide a novel probe of dark matter on extragalactic scales. We focus on luminous red galaxies (LRGs) as optimal targets to search for the signal of dark matter annihilation. We measure the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> of the EGB taken from the Fermi Large Area Telescope with the LRGs from the Sloan Digital Sky Survey. Statistical errors are calculated using a large set of realistic mock LRG catalogs. The amplitude of the measured <span class="hlt">cross-correlation</span> is consistent with null detection. Based on an accurate theoretical model of the distribution of dark matter associated with LRGs, we exclude dark matter annihilation cross-sections over ⟨σ v ⟩=3 ×10-25- 1 0-26 cm3 s-1 for a 10 GeV dark matter. We further investigate systematic effects due to uncertainties in the Galactic gamma-ray foreground emission, which we find to be an order of magnitude smaller than the current statistical uncertainty. We also estimate the contamination from astrophysical sources in the LRGs by using known scaling relations between gamma-ray luminosity and star-formation rate, finding them to be negligibly small. Based on these results, we suggest that LRGs remain ideal targets for probing dark matter annihilation with future EGB measurement and galaxy surveys. Increasing the number of LRGs in upcoming galaxy surveys such as LSST would lead to big improvements of factors of several in sensitivity.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S43B2517V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S43B2517V"><span>Study of the Piton de la Fournaise volcano using teleseismic waves from noise <span class="hlt">cross-correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Verbeke, J.; Shapiro, N.; Brenguier, F.; De Rosny, J.</p> <p>2013-12-01</p> <p>The ambient noise technique is based on the theoretical fact that the <span class="hlt">cross-correlation</span> of a random signal recorded at two locations contains the Green's <span class="hlt">functions</span> associated with those locations, one being treated as the source, the other as the receiver and vice versa. Because the surface-wave packet is the most energetic part of the signal, most of the noise-based studies have focused on the extraction of the surface waves to image the earth at crustal scale. More recently, body-waves signal have emerged out of the noise <span class="hlt">cross-correlations</span> both at regional and global scales. Correlations of year-long continuous records resulted in extraction of seismic body waves illuminating the mantle transition zone as well as the core-mantle boundary. In our study, we make an attempt to use the teleseismic body waves extracted from the noise to illuminate the structure below the Piton de la Fournaise volcano one of the most active volcanoes on the Earth. The Piton de la Fournaise located on La Réunion island is nowadays continuously recorded and monitored. Extraction of the body waves-from the noise would, therefore, allow us to monitor the deep parts of the volcano plumbing system. To study the feasibility of this approach, we <span class="hlt">cross-correlate</span> the continuous records from 21 broadband seismic stations operating on La Réunion island with continuous records from two high density networks: USArray and Hinet in Japan. Using these high-density networks gives us the opportunity to stack the information both in time and in space to enhance the signal of the body-waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoJI.203.1149L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoJI.203.1149L"><span>Extracting seismic attenuation coefficients from <span class="hlt">cross-correlations</span> of ambient noise at linear triplets of stations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Xin; Ben-Zion, Yehuda; Zigone, Dimitri</p> <p>2015-11-01</p> <p>We develop and apply an algorithm for deriving interstation seismic attenuation from <span class="hlt">cross-correlations</span> of ambient noise recorded by linear arrays. Theoretical results on amplitude decay due to attenuation are used to form a linear least-square inversion for interstation QR values of Rayleigh surface waves propagating along linear arrays having three or more stations. The noise wave field is assumed stationary within each day and the interstation distances should be greater than the employed wavelength. The inversion uses differences of logarithmic amplitude decay curves measured at different stations from <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> within a given frequency band. The background attenuation between noise sources and receivers is effectively cancelled with this method. The site amplification factors are assumed constant (or following similar patterns) in the frequency band of interest. The inversion scheme is validated with synthetic tests using ambient noise generated by ray-theory-based calculations with heterogeneous attenuation and homogenous velocity structure. The interstation attenuation and phase velocity dispersion curves are inverted from <span class="hlt">cross-correlations</span> of the synthetic data. The method is then applied to triplets of stations from the regional southern California seismic network crossing the Mojave section of the San Andreas fault, and a dense linear array crossing the southern San Jacinto Fault zone. Bootstrap technique is used to derive empirical mean and confidence interval for the obtained inverse Q values. The results for the regional stations yield QR values around 25 for a frequency band 0.2-0.36 Hz. The results for the San Jacinto fault zone array give QR values of about 6-30 for frequencies in the range 15-25 Hz.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009PhRvD..79d3509D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009PhRvD..79d3509D"><span>Measuring distance ratios with CMB-galaxy lensing <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Das, Sudeep; Spergel, David N.</p> <p>2009-02-01</p> <p>We propose a method for cosmographic measurements by combining gravitational lensing of the cosmic microwave background (CMB) with cosmic shear surveys. We <span class="hlt">cross-correlate</span> the galaxy counts in the lens plane with two different source planes: the CMB at z˜1100 and galaxies at an intermediate redshift. The ratio of the galaxy count/CMB lensing <span class="hlt">cross-correlation</span> to the galaxy count/galaxy lensing <span class="hlt">cross-correlation</span> is shown to be a purely geometric quantity, depending only on the distribution <span class="hlt">function</span> of the source galaxies. By combining Planck, the Advanced Dark Energy Physics Telescope, and the Large Synoptic Survey Telescope, the ratio can be measured to ˜4% accuracy, whereas a future polarization-based experiment like CMBPOL can make a more precise (˜1%) measurement. For cosmological models where the curvature and the equation of state parameter are allowed to vary, the direction of degeneracy defined by the measurement of this ratio is different from that traced out by baryon acoustic oscillation measurements. Combining this method with the stacked cluster mass reconstruction cosmography technique as proposed by Hu, Holz, and Vale (2007), the uncertainty in the ratio can be further reduced, improving the constraints on cosmological parameters. We also study the implications of the lensing-ratio measurement for early dark energy models, in the context of the parametrization proposed by Doran and Robbers (2006). For models which are degenerate with respect to the CMB, we find both baryon acoustic oscillation and lensing-ratio measurements to be insensitive to the early component of the dark energy density.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20586411','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20586411"><span>Fluorescence lifetime <span class="hlt">cross</span> <span class="hlt">correlation</span> spectroscopy resolves EGFR and antagonist interaction in live cells.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Jiji; Irudayaraj, Joseph</p> <p>2010-08-01</p> <p>Fluorescence correlation or <span class="hlt">cross-correlation</span> spectroscopy (FCS or FCCS), a single molecule technique, has the ability to provide highly sensitive information on interaction and dynamics of biomolecules both in vitro and in vivo. However, the inherent drawback of FCS is that species with similar molecular weight could not be differentiated. Although FCCS could resolve this through <span class="hlt">cross-correlation</span>, it suffers from nonideal confocal volume overlap and spectral cross-talk which limits its application. In this work, we demonstrate for the first time the applicability of fluorescence lifetime correlation spectroscopy (FLCS) to monitor the interaction of an antagonist antibody with the epidermal growth factor receptor (EGFR) in live cells. As a proof of concept, we demonstrate the interaction of Cy5 labeled IgG and Alexa633 labeled anti-IgG using a single laser source (636 nm excitation) in vitro. The autocorrelation <span class="hlt">functions</span> were separated based on their respective lifetime with a single detector and their K(d) value was determined to be 11 +/- 3 nM. An in vivo application constituting the interaction of EGFR neutralizing antibody labeled with Alexa488 and EGFR-GFP in live HEK293 cells was successfully demonstrated. The binding specificity of EGFR neutralizing antibody was confirmed by fluorescence lifetime <span class="hlt">cross-correlation</span> measurements and fluorescence lifetime imaging (FLIM). The dissociation constant of this complex was found to be 9.2 +/- 2.7 nM. A quantitative assessment of receptor density calculations show that the density of EGFR significantly decreased, from 540 +/- 64 receptors/microm(2) to 38 +/- 7 receptors/microm(2) upon addition of the neutralizing EGFR antibody, indicating that the antagonist could induce receptor internalization. The demonstrated work not only opens up new opportunities in studying protein-protein interactions in solutions and in live cells but also provide new insights in biology to understand how the antagonists influence EGFR</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010MNRAS.402....2B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010MNRAS.402....2B"><span><span class="hlt">Cross-correlation</span> of diffuse synchrotron and large-scale structures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brown, Shea; Farnsworth, Damon; Rudnick, Lawrence</p> <p>2010-02-01</p> <p>We explore for the first time the method of <span class="hlt">cross-correlation</span> of radio synchrotron emission and tracers of large-scale structure in order to detect the warm-hot intergalactic medium (WHIM). We performed a <span class="hlt">cross-correlation</span> of a 34° × 34° area of Two-Micron All-Sky Survey (2MASS) galaxies for two redshift slices (0.03 < z < 0.04 and 0.06 < z < 0.07) with the corresponding region of the 1.4 GHz Bonn survey. For this analysis, we assumed that the synchrotron surface brightness is linearly proportional to surface density of galaxies. We also sampled the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> (CCF) using 24 distant fields of the same size from the Bonn survey, to better assess the noise properties. Though we obtained a null result, we found that by adding a signal weighted by the 2MASS image with a filament (peak) surface brightness of 1 (7) and 7 (49) mK would produce a 3σ positive correlation for the 0.03 < z < 0.04 and 0.06 < z < 0.07 redshift slices, respectively. These detection thresholds correspond to minimum energy magnetic fields as low as 0.2 μG, close to some theoretical expectations for filament field values. This injected signal is also below the rms noise of the Bonn survey, and demonstrates the power of this technique and its utility for upcoming sensitive continuum surveys such as those planned with the Murchison Widefield Array.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.5989K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.5989K"><span>Detection and location of small aftershocks using waveform <span class="hlt">cross</span> <span class="hlt">correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kitov, Ivan; Sanina, Irina; Sergeev, Sergey</p> <p>2017-04-01</p> <p>Aftershock sequences of earthquakes with magnitudes 5.0 and lower are difficult to detect and locate by sparse regional networks. Signals from aftershocks with magnitudes 2 to 3 are usually below detection thresholds of standard 3-C seismic stations at near regional distances. For seismic events close in space, the method waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> (WCC) allows to reduce detection threshold by at least a unit of magnitude and to improve location precision to a few kilometers. Therefore, the WCC method is directly applicable to weak aftershock sequences. Here, we recover seismic activity after the earthquake near the town of Mariupol (Ukraine) occurred on August 7, 2016. The main shock was detected by many stations of the International monitoring system (IMS), including the closest primary IMS array stations AKASG (6.62 deg.) and BRTR (7.81), as well as 3-C station KBZ (5.00). The International data centre located this event (47.0013N, 37.5427E), estimated its origin time (08:15:4.1 UTC), magnitude (mb=4.5), and depth (6.8 km). This event was also detected by two array stations of the Institute for Dynamics of Geospheres (IDG) of the Russian Academy of Sciences: portable 3-C array RDON (3.28), which is the closest station, and MHVAR (7.96). Using signals from the main shock at five stations as waveform templates, we calculated continuous traces of <span class="hlt">cross</span> <span class="hlt">correlation</span> coefficient (CC) from the 7th to the 11th of August. We found that the best templates should include all regional phases, and thus, have the length from 80 s to 180 s. For detection, we used standard STA/LTA method with threshold depending on station. The accuracy of onset time estimation by the STA/LTA detector based on CC-traces is close to one sample, which varies from 0.05 s at BRTR to 0.005 s for RDON and MHVAR. Arrival times of all detected signals were reduced to origin times using the observed travel times from the main shock. Clusters of origin times are considered as event hypotheses in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26711670','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26711670"><span><span class="hlt">Functional</span> MRI evidence for the decline of word <span class="hlt">retrieval</span> and generation during normal aging.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Baciu, M; Boudiaf, N; Cousin, E; Perrone-Bertolotti, M; Pichat, C; Fournet, N; Chainay, H; Lamalle, L; Krainik, A</p> <p>2016-02-01</p> <p>This fMRI study aimed to explore the effect of normal aging on word <span class="hlt">retrieval</span> and generation. The question addressed is whether lexical production decline is determined by a direct mechanism, which concerns the language operations or is rather indirectly induced by a decline of executive <span class="hlt">functions</span>. Indeed, the main hypothesis was that normal aging does not induce loss of lexical knowledge, but there is only a general slowdown in <span class="hlt">retrieval</span> mechanisms involved in lexical processing, due to possible decline of the executive <span class="hlt">functions</span>. We used three tasks (verbal fluency, object naming, and semantic categorization). Two groups of participants were tested (Young, Y and Aged, A), without cognitive and psychiatric impairment and showing similar levels of vocabulary. Neuropsychological testing revealed that older participants had lower executive <span class="hlt">function</span> scores, longer processing speeds, and tended to have lower verbal fluency scores. Additionally, older participants showed higher scores for verbal automatisms and overlearned information. In terms of behavioral data, older participants performed as accurate as younger adults, but they were significantly slower for the semantic categorization and were less fluent for verbal fluency task. <span class="hlt">Functional</span> MRI analyses suggested that older adults did not simply activate fewer brain regions involved in word production, but they actually showed an atypical pattern of activation. Significant correlations between the BOLD (Blood Oxygen Level Dependent) signal of aging-related (A > Y) regions and cognitive scores suggested that this atypical pattern of the activation may reveal several compensatory mechanisms (a) to overcome the slowdown in <span class="hlt">retrieval</span>, due to the decline of executive <span class="hlt">functions</span> and processing speed and (b) to inhibit verbal automatic processes. The BOLD signal measured in some other aging-dependent regions did not correlate with the behavioral and neuropsychological scores, and the overactivation of these uncorrelated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26ES...69a2156Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26ES...69a2156Q"><span>Research on image <span class="hlt">retrieval</span> using deep convolutional neural network combining L1 regularization and PRelu activation <span class="hlt">function</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>QingJie, Wei; WenBin, Wang</p> <p>2017-06-01</p> <p>In this paper, the image <span class="hlt">retrieval</span> using deep convolutional neural network combined with regularization and PRelu activation <span class="hlt">function</span> is studied, and improves image <span class="hlt">retrieval</span> accuracy. Deep convolutional neural network can not only simulate the process of human brain to receive and transmit information, but also contains a convolution operation, which is very suitable for processing images. Using deep convolutional neural network is better than direct extraction of image visual features for image <span class="hlt">retrieval</span>. However, the structure of deep convolutional neural network is complex, and it is easy to over-fitting and reduces the accuracy of image <span class="hlt">retrieval</span>. In this paper, we combine L1 regularization and PRelu activation <span class="hlt">function</span> to construct a deep convolutional neural network to prevent over-fitting of the network and improve the accuracy of image <span class="hlt">retrieval</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002PhRvE..66e6110B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002PhRvE..66e6110B"><span>Large scale <span class="hlt">cross-correlations</span> in Internet traffic</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barthélemy, Marc; Gondran, Bernard; Guichard, Eric</p> <p>2002-11-01</p> <p>The Internet is a complex network of interconnected routers, and the existence of a collective behavior such as congestion suggests that the correlations between the different connections play a crucial role. It is thus critical to measure and quantify these correlations. We use methods of random matrix theory (RMT) to analyze the <span class="hlt">cross-correlation</span> matrix <ss>C</ss> of information flow changes of 650 connections between 26 routers of the French scientific network ``Renater.'' We find that <ss>C</ss> has the universal properties of the Gaussian orthogonal ensemble of random matrices: The distribution of eigenvalues-up to a rescaling that exhibits a typical correlation time of the order of 10 min-and the spacing distribution follow the predictions of RMT. There are some deviations for large eigenvalues which contain network-specific information and which identify genuine correlations between the connections. The study of the most correlated connections reveals the existence of ``active centers'' that are exchanging information with a large number of routers thereby inducing correlations between the corresponding connections. These strong correlations could be a reason for the observed self-similarity in the world-wide web traffic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26540588','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26540588"><span>Imaging fluorescence (<span class="hlt">cross</span>-) <span class="hlt">correlation</span> spectroscopy in live cells and organisms.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Krieger, Jan W; Singh, Anand P; Bag, Nirmalya; Garbe, Christoph S; Saunders, Timothy E; Langowski, Jörg; Wohland, Thorsten</p> <p>2015-12-01</p> <p>Single-plane illumination (SPIM) or total internal reflection fluorescence (TIRF) microscopes can be combined with fast and single-molecule-sensitive cameras to allow spatially resolved fluorescence (<span class="hlt">cross</span>-) <span class="hlt">correlation</span> spectroscopy (FCS or FCCS, hereafter referred to FCS/FCCS). This creates a powerful quantitative bioimaging tool that can generate spatially resolved mobility and interaction maps with hundreds to thousands of pixels per sample. These massively parallel imaging schemes also cause less photodamage than conventional single-point confocal microscopy-based FCS/FCCS. Here we provide guidelines for imaging FCS/FCCS measurements on commercial and custom-built microscopes (including sample preparation, setup calibration, data acquisition and evaluation), as well as anticipated results for a variety of in vitro and in vivo samples. For a skilled user of an available SPIM or TIRF setup, sample preparation, microscope alignment, data acquisition and data fitting, as described in this protocol, will take ∼1 d, depending on the sample and the mode of imaging.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12513559','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12513559"><span>Large scale <span class="hlt">cross-correlations</span> in Internet traffic.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Barthélemy, Marc; Gondran, Bernard; Guichard, Eric</p> <p>2002-11-01</p> <p>The Internet is a complex network of interconnected routers, and the existence of a collective behavior such as congestion suggests that the correlations between the different connections play a crucial role. It is thus critical to measure and quantify these correlations. We use methods of random matrix theory (RMT) to analyze the <span class="hlt">cross-correlation</span> matrix C of information flow changes of 650 connections between 26 routers of the French scientific network "Renater." We find that C has the universal properties of the Gaussian orthogonal ensemble of random matrices: The distribution of eigenvalues-up to a rescaling that exhibits a typical correlation time of the order of 10 min-and the spacing distribution follow the predictions of RMT. There are some deviations for large eigenvalues which contain network-specific information and which identify genuine correlations between the connections. The study of the most correlated connections reveals the existence of "active centers" that are exchanging information with a large number of routers thereby inducing correlations between the corresponding connections. These strong correlations could be a reason for the observed self-similarity in the world-wide web traffic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013IJHPC..27..178C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013IJHPC..27..178C"><span>Accelerating radio astronomy <span class="hlt">cross-correlation</span> with graphics processing units</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clark, M. A.; LaPlante, P. C.; Greenhill, L. J.</p> <p>2013-05-01</p> <p>We present a highly parallel implementation of the <span class="hlt">cross-correlation</span> of time-series data using graphics processing units (GPUs), which is scalable to hundreds of independent inputs and suitable for the processing of signals from 'large-Formula' arrays of many radio antennas. The computational part of the algorithm, the X-engine, is implemented efficiently on NVIDIA's Fermi architecture, sustaining up to 79% of the peak single-precision floating-point throughput. We compare performance obtained for hardware- and software-managed caches, observing significantly better performance for the latter. The high performance reported involves use of a multi-level data tiling strategy in memory and use of a pipelined algorithm with simultaneous computation and transfer of data from host to device memory. The speed of code development, flexibility, and low cost of the GPU implementations compared with application-specific integrated circuit (ASIC) and field programmable gate array (FPGA) implementations have the potential to greatly shorten the cycle of correlator development and deployment, for cases where some power-consumption penalty can be tolerated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1806f0004Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1806f0004Y"><span>Nonlinear ultrasonic measurements based on <span class="hlt">cross-correlation</span> filtering techniques</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yee, Andrew; Stewart, Dylan; Bunget, Gheorghe; Kramer, Patrick; Farinholt, Kevin; Friedersdorf, Fritz; Pepi, Marc; Ghoshal, Anindya</p> <p>2017-02-01</p> <p>Cyclic loading of mechanical components promotes the formation of dislocation dipoles in metals, which can serve as precursors to crack nucleation and ultimately lead to failure. In the laboratory setting, an acoustic nonlinearity parameter has been assessed as an effective indicator for characterizing the progression of fatigue damage precursors. However, the need to use monochromatic waves of medium-to-high acoustic energy has presented a constraint, making it problematic for use in field applications. This paper presents a potential approach for field measurement of acoustic nonlinearity by using general purpose ultrasonic pulser-receivers. Nonlinear ultrasonic measurements during fatigue testing were analyzed by the using contact and immersion pulse-through method. A novel <span class="hlt">cross-correlation</span> filtering technique was developed to extract the fundamental and higher harmonic waves from the signals. As in the case of the classic harmonic generation, the nonlinearity parameters of the second and third harmonics indicate a strong correlation with fatigue cycles. Consideration was given to potential nonlinearities in the measurement system, and tests have confirmed that measured second harmonic signals exhibit a linear dependence on the input signal strength, further affirming the conclusion that this parameter relates to damage precursor formation from cyclic loading.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18188650','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18188650"><span>A new family of distance <span class="hlt">functions</span> for perceptual similarity <span class="hlt">retrieval</span> of medical images.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Felipe, Joaquim Cezar; Traina, Caetano; Traina, Agma Juci Machado</p> <p>2009-04-01</p> <p>A long-standing challenge of content-based image <span class="hlt">retrieval</span> (CBIR) systems is the definition of a suitable distance <span class="hlt">function</span> to measure the similarity between images in an application context which complies with the human perception of similarity. In this paper, we present a new family of distance <span class="hlt">functions</span>, called attribute concurrence influence distances (AID), which serve to <span class="hlt">retrieve</span> images by similarity. These distances address an important aspect of the psychophysical notion of similarity in comparisons of images: the effect of concurrent variations in the values of different image attributes. The AID <span class="hlt">functions</span> allow for comparisons of feature vectors by choosing one of two parameterized expressions: one targeting weak attribute concurrence influence and the other for strong concurrence influence. This paper presents the mathematical definition and implementation of the AID family for a two-dimensional feature space and its extension to any dimension. The composition of the AID family with L (p) distance family is considered to propose a procedure to determine the best distance for a specific application. Experimental results involving several sets of medical images demonstrate that, taking as reference the perception of the specialist in the field (radiologist), the AID <span class="hlt">functions</span> perform better than the general distance <span class="hlt">functions</span> commonly used in CBIR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950032547&hterms=stratospheric+aerosols+injection&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dstratospheric%2Baerosols%2Binjection','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950032547&hterms=stratospheric+aerosols+injection&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dstratospheric%2Baerosols%2Binjection"><span>Size distribution and scattering phase <span class="hlt">function</span> of aerosol particles <span class="hlt">retrieved</span> from sky brightness measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kaufman, Y. J.; Gitelson, A.; Karnieli, A.; Ganor, E. (Editor); Fraser, R. S.; Nakajima, T.; Mattoo, S.; Holben, B. N.</p> <p>1994-01-01</p> <p>Ground-based measurements of the solar transmission and sky radiance in a horizontal plane through the Sun are taken in several geographical regions and aerosol types: dust in a desert transition zone in Israel, sulfate particles in Eastern and Western Europe, tropical aerosol in Brazil, and mixed continental/maritime aerosol in California. Stratospheric aerosol was introduced after the eruption of Mount Pinatubo in June 1991. Therefore measurements taken before the eruption are used to analyze the properties of tropospheric aerosol; measurements from 1992 are also used to detect the particle size and concentration of stratospheric aerosol. The measurements are used to <span class="hlt">retrieve</span> the size distribution and the scattering phase <span class="hlt">function</span> at large scattering angles of the undisturbed aerosol particles. The <span class="hlt">retrieved</span> properties represent an average on the entire atmospheric column. A comparison between the <span class="hlt">retrieved</span> phase <span class="hlt">function</span> for a scattering angle of 120 deg, with phase <span class="hlt">function</span> predicted from the <span class="hlt">retrieved</span> size distribution, is used to test the assumption of particle homogeneity and sphericity in radiative transfer models (Mie theory). The effect was found to be small (20% +/- 15%). For the stratospheric aerosol (sulfates), as expected, the phase <span class="hlt">function</span> was very well predicted using the Mie theory. A model with a power law distribution, based on the spectral dependence of the optical thickness, alpha, cannot estimate accurately the phase <span class="hlt">function</span> (up to 50% error for lambda = 0.87 microns). Before the Pinatubo eruption the ratio between the volumes of sulfate and coarse particles was very well correlated with alpha. The Pinatubo stratospheric aerosol destroyed this correlation. The aerosol optical properties are compared with analysis of the size, shape, and composition of the individual particles by electron microscopy of in situ samples. The measured volume size distribution before the injection of stratospheric aerosol consistently show two modes, sulfate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994JGR....9910341K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994JGR....9910341K"><span>Size distribution and scattering phase <span class="hlt">function</span> of aerosol particles <span class="hlt">retrieved</span> from sky brightness measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kaufman, Y. J.; Gitelson, A.; Karnieli, A.; Ganor, E.; Fraser, R. S.; Nakajima, T.; Mattoo, S.; Holben, B. N.</p> <p>1994-05-01</p> <p>Ground-based measurements of the solar transmission and sky radiance in a horizontal plane through the Sun are taken in several geographical regions and aerosol types: dust in a desert transition zone in Israel, sulfate particles in Eastern and Western Europe, tropical aerosol in Brazil, and mixed continental/maritime aerosol in California. Stratospheric aerosol was introduced after the eruption of Mount Pinatubo in June 1991. Therefore measurements taken before the eruption are used to analyze the properties of tropospheric aerosol; measurements from 1992 are also used to detect the particle size and concentration of stratospheric aerosol. The measurements are used to <span class="hlt">retrieve</span> the size distribution and the scattering phase <span class="hlt">function</span> at large scattering angles of the undisturbed aerosol particles. The <span class="hlt">retrieved</span> properties represent an average on the entire atmospheric column. A comparison between the <span class="hlt">retrieved</span> phase <span class="hlt">function</span> for a scattering angle of 120°, with phase <span class="hlt">function</span> predicted from the <span class="hlt">retrieved</span> size distribution, is used to test the assumption of particle homogeneity and sphericity in radiative transfer models (Mie theory). The effect was found to be small (20%±15%). For the stratospheric aerosol (sulfates), as expected, the phase <span class="hlt">function</span> was very well predicted using the Mie theory. A model with a power law size distribution, based on the spectral dependence of the optical thickness, a, cannot estimate accurately the phase <span class="hlt">function</span> (up to 50% error for λ = 0.87 μm). Before the Pinatubo eruption the ratio between the volumes of sulfate and coarse particles was very well correlated with α. The Pinatubo stratospheric aerosol destroyed this correlation. The aerosol optical properties are compared with analysis of the size, shape, and composition of the individual particles by electron microscopy of in situ samples. The measured volume size distributions before the injection of stratospheric aerosol consistently show two modes, sulfate particles with rm</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950032547&hterms=transmission+distribution&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dtransmission%2Bdistribution','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950032547&hterms=transmission+distribution&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dtransmission%2Bdistribution"><span>Size distribution and scattering phase <span class="hlt">function</span> of aerosol particles <span class="hlt">retrieved</span> from sky brightness measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kaufman, Y. J.; Gitelson, A.; Karnieli, A.; Ganor, E. (Editor); Fraser, R. S.; Nakajima, T.; Mattoo, S.; Holben, B. N.</p> <p>1994-01-01</p> <p>Ground-based measurements of the solar transmission and sky radiance in a horizontal plane through the Sun are taken in several geographical regions and aerosol types: dust in a desert transition zone in Israel, sulfate particles in Eastern and Western Europe, tropical aerosol in Brazil, and mixed continental/maritime aerosol in California. Stratospheric aerosol was introduced after the eruption of Mount Pinatubo in June 1991. Therefore measurements taken before the eruption are used to analyze the properties of tropospheric aerosol; measurements from 1992 are also used to detect the particle size and concentration of stratospheric aerosol. The measurements are used to <span class="hlt">retrieve</span> the size distribution and the scattering phase <span class="hlt">function</span> at large scattering angles of the undisturbed aerosol particles. The <span class="hlt">retrieved</span> properties represent an average on the entire atmospheric column. A comparison between the <span class="hlt">retrieved</span> phase <span class="hlt">function</span> for a scattering angle of 120 deg, with phase <span class="hlt">function</span> predicted from the <span class="hlt">retrieved</span> size distribution, is used to test the assumption of particle homogeneity and sphericity in radiative transfer models (Mie theory). The effect was found to be small (20% +/- 15%). For the stratospheric aerosol (sulfates), as expected, the phase <span class="hlt">function</span> was very well predicted using the Mie theory. A model with a power law distribution, based on the spectral dependence of the optical thickness, alpha, cannot estimate accurately the phase <span class="hlt">function</span> (up to 50% error for lambda = 0.87 microns). Before the Pinatubo eruption the ratio between the volumes of sulfate and coarse particles was very well correlated with alpha. The Pinatubo stratospheric aerosol destroyed this correlation. The aerosol optical properties are compared with analysis of the size, shape, and composition of the individual particles by electron microscopy of in situ samples. The measured volume size distribution before the injection of stratospheric aerosol consistently show two modes, sulfate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25073927','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25073927"><span>Enhancement of encoding and <span class="hlt">retrieval</span> <span class="hlt">functions</span> through theta phase-specific manipulation of hippocampus.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Siegle, Joshua H; Wilson, Matthew A</p> <p>2014-07-29</p> <p>Assessing the behavioral relevance of the hippocampal theta rhythm has proven difficult, due to a shortage of experiments that selectively manipulate phase-specific information processing. Using closed-loop stimulation, we triggered inhibition of dorsal CA1 at specific phases of the endogenous theta rhythm in freely behaving mice. This intervention enhanced performance on a spatial navigation task that requires the encoding and <span class="hlt">retrieval</span> of information related to reward location on every trial. In agreement with prior models of hippocampal <span class="hlt">function</span>, the behavioral effects depended on both the phase of theta and the task segment at which we stimulated. Stimulation in the encoding segment enhanced performance when inhibition was triggered by the peak of theta. Conversely, stimulation in the <span class="hlt">retrieval</span> segment enhanced performance when inhibition was triggered by the trough of theta. These results suggest that processes related to the encoding and <span class="hlt">retrieval</span> of task-relevant information are preferentially active at distinct phases of theta.DOI: http://dx.doi.org/10.7554/eLife.03061.001. Copyright © 2014, Siegle and Wilson.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRC..119.5360Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRC..119.5360Y"><span>Aquarius geophysical model <span class="hlt">function</span> and combined active passive algorithm for ocean surface salinity and wind <span class="hlt">retrieval</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yueh, Simon; Tang, Wenqing; Fore, Alexander; Hayashi, Akiko; Song, Yuhe T.; Lagerloef, Gary</p> <p>2014-08-01</p> <p>This paper describes the updated Combined Active-Passive (CAP) <span class="hlt">retrieval</span> algorithm for simultaneous <span class="hlt">retrieval</span> of surface salinity and wind from Aquarius' brightness temperature and radar backscatter. Unlike the algorithm developed by Remote Sensing Systems (RSS), implemented in the Aquarius Data Processing System (ADPS) to produce Aquarius standard products, the Jet Propulsion Laboratory's CAP algorithm does not require monthly climatology SSS maps for the salinity <span class="hlt">retrieval</span>. Furthermore, the ADPS-RSS algorithm fully uses the National Center for Environmental Predictions (NCEP) wind for data correction, while the CAP algorithm uses the NCEP wind only as a constraint. The major updates to the CAP algorithm include the galactic reflection correction, Faraday rotation, Antenna Pattern Correction, and geophysical model <span class="hlt">functions</span> of wind or wave impacts. Recognizing the limitation of geometric optics scattering, we improve the modeling of the reflection of galactic radiation; the results are better salinity accuracy and significantly reduced ascending-descending bias. We assess the accuracy of CAP's salinity by comparison with ARGO monthly gridded salinity products provided by the Asia-Pacific Data-Research Center (APDRC) and Japan Agency for Marine-Earth Science and Technology (JAMSTEC). The RMS differences between Aquarius CAP and APDRC's or JAMSTEC's ARGO salinities are less than 0.2 psu for most parts of the ocean, except for the regions in the Intertropical Convergence Zone, near the outflow of major rivers and at high latitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApJ...802L...1F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApJ...802L...1F"><span>Evidence of <span class="hlt">Cross-correlation</span> between the CMB Lensing and the γ-Ray Sky</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fornengo, Nicolao; Perotto, Laurence; Regis, Marco; Camera, Stefano</p> <p>2015-03-01</p> <p>We report the measurement of the angular power spectrum of <span class="hlt">cross-correlation</span> between the unresolved component of the Fermi-LAT γ-ray sky maps and the cosmic microwave background lensing potential map reconstructed by the Planck satellite. The matter distribution in the universe determines the bending of light coming from the last scattering surface. At the same time, the matter density drives the growth history of astrophysical objects, including their capability at generating non-thermal phenomena, which in turn give rise to γ-ray emissions. The Planck lensing map provides information on the integrated distribution of matter, while the integrated history of γ-ray emitters is imprinted in the Fermi-LAT sky maps. We report here the first evidence of their correlation. We find that the multipole dependence of the <span class="hlt">cross-correlation</span> measurement is in agreement with current models of the γ-ray luminosity <span class="hlt">function</span> for active galactic nuclei and star-forming galaxies, with a statistical evidence of 3.0σ. Moreover, its amplitude can in general be matched only assuming that these extragalactic emitters are also the bulk contribution of the measured isotopic γ-ray background (IGRB) intensity. This leaves little room for a big contribution from galactic sources to the IGRB measured by Fermi-LAT, pointing toward direct evidence of the extragalactic origin of the IGRB.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22518818','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22518818"><span>EVIDENCE OF <span class="hlt">CROSS-CORRELATION</span> BETWEEN THE CMB LENSING AND THE γ-RAY SKY</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fornengo, Nicolao; Regis, Marco; Perotto, Laurence</p> <p>2015-03-01</p> <p>We report the measurement of the angular power spectrum of <span class="hlt">cross-correlation</span> between the unresolved component of the Fermi-LAT γ-ray sky maps and the cosmic microwave background lensing potential map reconstructed by the Planck satellite. The matter distribution in the universe determines the bending of light coming from the last scattering surface. At the same time, the matter density drives the growth history of astrophysical objects, including their capability at generating non-thermal phenomena, which in turn give rise to γ-ray emissions. The Planck lensing map provides information on the integrated distribution of matter, while the integrated history of γ-ray emitters is imprinted in the Fermi-LAT sky maps. We report here the first evidence of their correlation. We find that the multipole dependence of the <span class="hlt">cross-correlation</span> measurement is in agreement with current models of the γ-ray luminosity <span class="hlt">function</span> for active galactic nuclei and star-forming galaxies, with a statistical evidence of 3.0σ. Moreover, its amplitude can in general be matched only assuming that these extragalactic emitters are also the bulk contribution of the measured isotopic γ-ray background (IGRB) intensity. This leaves little room for a big contribution from galactic sources to the IGRB measured by Fermi-LAT, pointing toward direct evidence of the extragalactic origin of the IGRB.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003APS..DFD.MM012H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003APS..DFD.MM012H"><span>Lip pressure/velocity <span class="hlt">cross</span> <span class="hlt">correlations</span> in an axisymmetric, compressible jet.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hall, Andre'; Tinney, Charles; Glauser, Mark</p> <p>2003-11-01</p> <p>The <span class="hlt">cross</span> <span class="hlt">correlation</span> between fluctuating lip pressure and the instantaneous stream-wise velocity of a 2-inch diameter, cold (104oF), high Mach number, axisymmetric, jet with a maximum co-flow of 5velocity measurements are acquired using a Dantec Dynamic LDA/PDA system with a Stabilite 2017 argon ion laser head, capable of capturing all three components (u,v,w) of the velocity field. Pressure fluctuations at the lip of the nozzle are measured by an array of fifteen Kulite pressure transducers distributed azimuthally at the jet lip. The pressure-velocity <span class="hlt">cross</span> <span class="hlt">correlation</span> is then determined as a <span class="hlt">function</span> of radial, azimuthal, and stream-wise location. The results from this investigation provide a foundation for future studies where the instantaneous velocity field will be estimated, using a Linear Stochastic Estimation technique, from the fluctuating lip pressure alone. These results are also compared with measurements taken via stereo PIV in the same facility under identical conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGE....14..841L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGE....14..841L"><span><span class="hlt">Cross-correlation</span> least-squares reverse time migration in the pseudo-time domain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Qingyang; Huang, Jianping; Li, Zhenchun</p> <p>2017-08-01</p> <p>The least-squares reverse time migration (LSRTM) method with higher image resolution and amplitude is becoming increasingly popular. However, the LSRTM is not widely used in field land data processing because of its sensitivity to the initial migration velocity model, large computational cost and mismatch of amplitudes between the synthetic and observed data. To overcome the shortcomings of the conventional LSRTM, we propose a <span class="hlt">cross-correlation</span> least-squares reverse time migration algorithm in pseudo-time domain (PTCLSRTM). Our algorithm not only reduces the depth/velocity ambiguities, but also reduces the effect of velocity error on the imaging results. It relieves the accuracy requirements on the migration velocity model of least-squares migration (LSM). The pseudo-time domain algorithm eliminates the irregular wavelength sampling in the vertical direction, thus it can reduce the vertical grid points and memory requirements used during computation, which makes our method more computationally efficient than the standard implementation. Besides, for field data applications, matching the recorded amplitudes is a very difficult task because of the viscoelastic nature of the Earth and inaccuracies in the estimation of the source wavelet. To relax the requirement for strong amplitude matching of LSM, we extend the normalized <span class="hlt">cross-correlation</span> objective <span class="hlt">function</span> to the pseudo-time domain. Our method is only sensitive to the similarity between the predicted and the observed data. Numerical tests on synthetic and land field data confirm the effectiveness of our method and its adaptability for complex models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22373569','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22373569"><span>Quasar-Lyman α forest <span class="hlt">cross-correlation</span> from BOSS DR11: Baryon Acoustic Oscillations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Font-Ribera, Andreu; Kirkby, David; Blomqvist, Michael; Busca, Nicolas; Aubourg, Éric; Bautista, Julian; Ross, Nicholas P.; Bailey, Stephen; Beutler, Florian; Carithers, Bill; Slosar, Anže; Rich, James; Delubac, Timothée; Bhardwaj, Vaishali; Bizyaev, Dmitry; Brewington, Howard; Brinkmann, Jon; Brownstein, Joel R.; Dawson, Kyle S.; and others</p> <p>2014-05-01</p> <p>We measure the large-scale <span class="hlt">cross-correlation</span> of quasars with the Lyα forest absorption, using over 164,000 quasars from Data Release 11 of the SDSS-III Baryon Oscillation Spectroscopic Survey. We extend the previous study of roughly 60,000 quasars from Data Release 9 to larger separations, allowing a measurement of the Baryonic Acoustic Oscillation (BAO) scale along the line of sight c/(H(z = 2.36)r{sub s}) = 9.0±0.3 and across the line of sight D{sub A}(z = 2.36)/r{sub s} = 10.8±0.4, consistent with CMB and other BAO data. Using the best fit value of the sound horizon from Planck data (r{sub s} = 147.49 Mpc), we can translate these results to a measurement of the Hubble parameter of H(z = 2.36) = 226±8 km s{sup −1} Mpc{sup −1} and of the angular diameter distance of D{sub A}(z = 2.36) = 1590±60 Mpc. The measured <span class="hlt">cross-correlation</span> <span class="hlt">function</span> and an update of the code to fit the BAO scale (baofit) are made publicly available.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JCAP...05..027F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JCAP...05..027F"><span>Quasar-Lyman α forest <span class="hlt">cross-correlation</span> from BOSS DR11: Baryon Acoustic Oscillations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Font-Ribera, Andreu; Kirkby, David; Busca, Nicolas; Miralda-Escudé, Jordi; Ross, Nicholas P.; Slosar, Anže; Rich, James; Aubourg, Éric; Bailey, Stephen; Bhardwaj, Vaishali; Bautista, Julian; Beutler, Florian; Bizyaev, Dmitry; Blomqvist, Michael; Brewington, Howard; Brinkmann, Jon; Brownstein, Joel R.; Carithers, Bill; Dawson, Kyle S.; Delubac, Timothée; Ebelke, Garrett; Eisenstein, Daniel J.; Ge, Jian; Kinemuchi, Karen; Lee, Khee-Gan; Malanushenko, Viktor; Malanushenko, Elena; Marchante, Moses; Margala, Daniel; Muna, Demitri; Myers, Adam D.; Noterdaeme, Pasquier; Oravetz, Daniel; Palanque-Delabrouille, Nathalie; Pâris, Isabelle; Petitjean, Patrick; Pieri, Matthew M.; Rossi, Graziano; Schneider, Donald P.; Simmons, Audrey; Viel, Matteo; Yeche, Christophe; York, Donald G.</p> <p>2014-05-01</p> <p>We measure the large-scale <span class="hlt">cross-correlation</span> of quasars with the Lyα forest absorption, using over 164,000 quasars from Data Release 11 of the SDSS-III Baryon Oscillation Spectroscopic Survey. We extend the previous study of roughly 60,000 quasars from Data Release 9 to larger separations, allowing a measurement of the Baryonic Acoustic Oscillation (BAO) scale along the line of sight c/(H(z = 2.36)rs) = 9.0±0.3 and across the line of sight DA(z = 2.36)/rs = 10.8±0.4, consistent with CMB and other BAO data. Using the best fit value of the sound horizon from Planck data (rs = 147.49 Mpc), we can translate these results to a measurement of the Hubble parameter of H(z = 2.36) = 226±8 km s-1 Mpc-1 and of the angular diameter distance of DA(z = 2.36) = 1590±60 Mpc. The measured <span class="hlt">cross-correlation</span> <span class="hlt">function</span> and an update of the code to fit the BAO scale (baofit) are made publicly available.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..1110340S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..1110340S"><span>On the Balancing of the SMOS Ocean Salinity <span class="hlt">Retrieval</span> Cost <span class="hlt">Function</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sabia, R.; Camps, A.; Portabella, M.; Talone, M.; Ballabrera, J.; Gourrion, J.; Gabarró, C.; Aretxabaleta, A. L.; Font, J.</p> <p>2009-04-01</p> <p>The Soil Moisture and Ocean Salinity (SMOS) mission will be launched in mid 2009 to provide synoptic sea surface salinity (SSS) measurements with good temporal resolution [1]. To obtain a proper estimation of the SSS fields derived from the multi-angular brightness temperatures (TB) measured by the Microwave Interferometric Radiometer by Aperture Synthesis (MIRAS) sensor, a comprehensive inversion procedure has been defined [2]. Nevertheless, several salinity <span class="hlt">retrieval</span> issues remain critical, namely: 1) Scene-dependent bias in the simulated TBs, 2) L-band forward geophysical model <span class="hlt">function</span> definition, 3) Auxiliary data uncertainties, 4) Constraints in the cost <span class="hlt">function</span> (inversion), especially in salinity term, and 5) Adequate spatio-temporal averaging. These issues will have to be properly addressed in order to meet the proposed accuracy requirement of the mission: a demanding 0.1 psu (practical salinity units) after averaging in a 30-day and 2°x2° spatio-temporal boxes. The salinity <span class="hlt">retrieval</span> cost <span class="hlt">function</span> minimizes the difference between the multi-angular measured SMOS TBs (yet simulated, so far) and the modeled TBs, weighted by the corresponding radiometric noise of the measurements. Furthermore, due to the fact that the minimization problem is both non-linear and ill-posed, background reference terms are needed to nudge the solution and ensuring convergence at the same time [3]. Constraining terms in SSS, sea surface temperature (SST) and wind speed are considered with their respective uncertainties. Moreover, whether SSS constraints have to be included or not as part of the <span class="hlt">retrieval</span> procedure is still a matter of debate. On one hand, neglecting background reference information on SSS might prevent from <span class="hlt">retrieving</span> salinity with the prescribed accuracy or at least within reasonable error. Conversely, including constraints in SSS, relying for instance on the climatology, may force the <span class="hlt">retrieved</span> value to be too close to the reference prior values, thus</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AtmEn.146..206D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AtmEn.146..206D"><span>Exploring lag times between monthly atmospheric deposition and stream chemistry in Appalachian forests using <span class="hlt">cross-correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>DeWalle, David R.; Boyer, Elizabeth W.; Buda, Anthony R.</p> <p>2016-12-01</p> <p>Forecasts of ecosystem changes due to variations in atmospheric emissions policies require a fundamental understanding of lag times between changes in chemical inputs and watershed response. Impacts of changes in atmospheric deposition in the United States have been documented using national and regional long-term environmental monitoring programs beginning several decades ago. Consequently, time series of weekly NADP atmospheric wet deposition and monthly EPA-Long Term Monitoring stream chemistry now exist for much of the Northeast which may provide insights into lag times. In this study of Appalachian forest basins, we estimated lag times for S, N and Cl by <span class="hlt">cross-correlating</span> monthly data from four pairs of stream and deposition monitoring sites during the period from 1978 to 2012. A systems or impulse response <span class="hlt">function</span> approach to <span class="hlt">cross-correlation</span> was used to estimate lag times where the input deposition time series was pre-whitened using regression modeling and the stream response time series was filtered using the deposition regression model prior to <span class="hlt">cross-correlation</span>. <span class="hlt">Cross-correlations</span> for S were greatest at annual intervals over a relatively well-defined range of lags with the maximum correlations occurring at mean lags of 48 months. Chloride results were similar but more erratic with a mean lag of 57 months. Few high-correlation lags for N were indicated. Given the growing availability of atmospheric deposition and surface water chemistry monitoring data and our results for four Appalachian basins, further testing of <span class="hlt">cross-correlation</span> as a method of estimating lag times on other basins appears justified.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5380065','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5380065"><span>Dynamic <span class="hlt">cross-correlations</span> between entangled biofilaments as they diffuse</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Tsang, Boyce; Dell, Zachary E.; Jiang, Lingxiang; Schweizer, Kenneth S.; Granick, Steve</p> <p>2017-01-01</p> <p>Entanglement in polymer and biological physics involves a state in which linear interthreaded macromolecules in isotropic liquids diffuse in a spatially anisotropic manner beyond a characteristic mesoscopic time and length scale (tube diameter). The physical reason is that linear macromolecules become transiently localized in directions transverse to their backbone but diffuse with relative ease parallel to it. Within the resulting broad spectrum of relaxation times there is an extended period before the longest relaxation time when filaments occupy a time-averaged cylindrical space of near-constant density. Here we show its implication with experiments based on fluorescence tracking of dilutely labeled macromolecules. The entangled pairs of aqueous F-actin biofilaments diffuse with separation-dependent dynamic <span class="hlt">cross-correlations</span> that exceed those expected from continuum hydrodynamics up to strikingly large spatial distances of ≈15 µm, which is more than 104 times the size of the solvent water molecules in which they are dissolved, and is more than 50 times the dynamic tube diameter, but is almost equal to the filament length. Modeling this entangled system as a collection of rigid rods, we present a statistical mechanical theory that predicts these long-range dynamic correlations as an emergent consequence of an effective long-range interpolymer repulsion due to the de Gennes correlation hole, which is a combined consequence of chain connectivity and uncrossability. The key physical assumption needed to make theory and experiment agree is that solutions of entangled biofilaments localized in tubes that are effectively dynamically incompressible over the relevant intermediate time and length scales. PMID:28283664</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28283664','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28283664"><span>Dynamic <span class="hlt">cross-correlations</span> between entangled biofilaments as they diffuse.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tsang, Boyce; Dell, Zachary E; Jiang, Lingxiang; Schweizer, Kenneth S; Granick, Steve</p> <p>2017-03-10</p> <p>Entanglement in polymer and biological physics involves a state in which linear interthreaded macromolecules in isotropic liquids diffuse in a spatially anisotropic manner beyond a characteristic mesoscopic time and length scale (tube diameter). The physical reason is that linear macromolecules become transiently localized in directions transverse to their backbone but diffuse with relative ease parallel to it. Within the resulting broad spectrum of relaxation times there is an extended period before the longest relaxation time when filaments occupy a time-averaged cylindrical space of near-constant density. Here we show its implication with experiments based on fluorescence tracking of dilutely labeled macromolecules. The entangled pairs of aqueous F-actin biofilaments diffuse with separation-dependent dynamic <span class="hlt">cross-correlations</span> that exceed those expected from continuum hydrodynamics up to strikingly large spatial distances of ≈15 µm, which is more than 10(4) times the size of the solvent water molecules in which they are dissolved, and is more than 50 times the dynamic tube diameter, but is almost equal to the filament length. Modeling this entangled system as a collection of rigid rods, we present a statistical mechanical theory that predicts these long-range dynamic correlations as an emergent consequence of an effective long-range interpolymer repulsion due to the de Gennes correlation hole, which is a combined consequence of chain connectivity and uncrossability. The key physical assumption needed to make theory and experiment agree is that solutions of entangled biofilaments localized in tubes that are effectively dynamically incompressible over the relevant intermediate time and length scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..483..362R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..483..362R"><span>The effects of common risk factors on stock returns: A detrended <span class="hlt">cross-correlation</span> analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruan, Qingsong; Yang, Bingchan</p> <p>2017-10-01</p> <p>In this paper, we investigate the <span class="hlt">cross-correlations</span> between Fama and French three factors and the return of American industries on the basis of <span class="hlt">cross-correlation</span> statistic test and multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA). Qualitatively, we find that the return series of Fama and French three factors and American industries were overall significantly <span class="hlt">cross-correlated</span> based on the analysis of a statistic. Quantitatively, we find that the <span class="hlt">cross-correlations</span> between three factors and the return of American industries were strongly multifractal, and applying MF-DCCA we also investigate the <span class="hlt">cross-correlation</span> of industry returns and residuals. We find that there exists multifractality of industry returns and residuals. The result of correlation coefficients we can verify that there exist other factors which influence the industry returns except Fama three factors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28986084','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28986084"><span>On the <span class="hlt">functional</span> significance of <span class="hlt">retrieval</span> mode: Task switching disrupts the recollection of conceptual stimulus information from episodic memory.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Küper, Kristina</p> <p>2017-10-03</p> <p>Episodic memory <span class="hlt">retrieval</span> is assumed to be associated with the tonic cognitive state of <span class="hlt">retrieval</span> mode. Despite extensive research into the neurophysiological correlates of <span class="hlt">retrieval</span> mode, as of yet, relatively little is known about its <span class="hlt">functional</span> significance. The present event-related potential (ERP) study was aimed at examining the impact of <span class="hlt">retrieval</span> mode on the specificity of memory content <span class="hlt">retrieved</span> in the course of familiarity and recollection processes. In two experiments, participants performed a recognition memory inclusion task in which they had to distinguish identically repeated and re-colored versions of study items from new items. In Experiment 1, participants had to alternate between the episodic memory task and a semantic task requiring a natural/artificial decision. In Experiment 2, the two tasks were instead performed in separate blocks. ERPs locked to the preparatory cues in the test phases indicated that participants did not establish <span class="hlt">retrieval</span> mode on switch trials in Experiment 1. In the absence of <span class="hlt">retrieval</span> mode, neither type of studied item elicited ERP correlates of familiarity-based <span class="hlt">retrieval</span> (FN400). Recollection-related late positive complex (LPC) old/new effects emerged only for identically repeated but not for conceptually identical but perceptually changed versions of study items. With blocked <span class="hlt">retrieval</span> in Experiment 2, both types of old items instead elicited equivalent FN400 and LPC old/new effects. The LPC data indicate that <span class="hlt">retrieval</span> mode may play an important role in the successful recollection of conceptual stimulus information. The FN400 results additionally suggest that task switching may have a detrimental effect on familiarity-based memory <span class="hlt">retrieval</span>. Copyright © 2017 Elsevier B.V. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1915138M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1915138M"><span><span class="hlt">Retrieving</span> Source-Time <span class="hlt">Function</span> and Seismic Moment Tensor From Near Field Records</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morales, Catalina; Ruiz, Javier A.; Ortega, Francisco; Rivera, Luis</p> <p>2017-04-01</p> <p><span class="hlt">Retrieve</span> earthquake source parameters from seismological or geodetic data is an important aspect in the rapid characterization of the earthquake source, which is particularly relevant in real-time operations. The inversion of seismic moment tensors and slip distributions of large earthquakes is a recurrent and important topic in seismology because it allows to know the source properties and rupture process. Several methodologies allow to make these inferences assuming different levels of complexity of the earthquake source, for instance, the Global Centroid Moment Tensor compute routinely the centroid moment tensor from global seismic data, on the other hand, agencies such as the National Earthquake Information Center have implemented methodologies to <span class="hlt">retrieve</span> the moment tensor in real-time (e.g the W-Phase). However, the joint inversion of the moment tensor and the source-time <span class="hlt">function</span> using regional and near-field data is a promising approach to characterize source parameters. Several methodologies allow to invert the seismic moment tensor using broadband regional data assuming a simple source-time <span class="hlt">function</span> (e.g. impulsive, or with a triangular shape), but are usually limited because broadband stations get saturated near the source for moderate and large earthquakes. Yagi and Nishimura (2011) proposed a method that inverts the moment tensor and the half duration using strong motion data. Weber (2009) computes the seismic moment tensor as a <span class="hlt">function</span> of time using broadband regional data, applying a inverse method that minimize the L1-norm, and then <span class="hlt">retrieves</span> the source-time <span class="hlt">function</span>. The aim of this study is to develop a method and a computational tool that allows to jointly invert the moment tensor and the source-time <span class="hlt">function</span> using strong motion and broadband regional data. The inverse method is applied in two steps, (1) we invert the moment tensor assuming a triangular source-time <span class="hlt">function</span> and, (2) minimizing the L2-norm, we invert the amplitude of a series of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930070913&hterms=blue+ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dblue%2Bocean','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930070913&hterms=blue+ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dblue%2Bocean"><span><span class="hlt">Retrieval</span> of the columnar aerosol phase <span class="hlt">function</span> and single-scattering albedo from sky radiance over the ocean - Simulations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wang, Menghua; Gordon, Howard R.</p> <p>1993-01-01</p> <p>Based on the fact that the part of downward radiance that depends on the optical properties of the aerosol in the atmosphere can be extracted from the measured sky radiance, a new scheme for <span class="hlt">retrieval</span> of the aerosol phase <span class="hlt">function</span> and the single-scattering albedo over the ocean is developed. This <span class="hlt">retrieval</span> algorithm is tested with simulations for several cases. It is found that the <span class="hlt">retrieved</span> aerosol phase <span class="hlt">function</span> and the single-scattering albedo are virtually error-free if the vertical structure of the atmosphere is known and if the sky radiance and the aerosol optical thickness can be measured accurately. The robustness of the algorithm in realistic situations, in which the measurements are contaminated by calibration errors or noise, is examined. It is found that the <span class="hlt">retrieved</span> value of omega(0) is usually in error by less than about 10 percent, and the phase <span class="hlt">function</span> is accurately <span class="hlt">retrieved</span> for theta less than about 90 deg. However, as the aerosol optical thickness becomes small, e.g., less than about 0.1, errors in the sky radiance measurement can lead to serious problems with the <span class="hlt">retrieval</span> algorithm, especially in the blue. The use of the <span class="hlt">retrieval</span> scheme should be limited to the red and near IR when the aerosol optical thickness is small.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930070913&hterms=Miami+Blue&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DMiami%2BBlue','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930070913&hterms=Miami+Blue&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DMiami%2BBlue"><span><span class="hlt">Retrieval</span> of the columnar aerosol phase <span class="hlt">function</span> and single-scattering albedo from sky radiance over the ocean - Simulations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wang, Menghua; Gordon, Howard R.</p> <p>1993-01-01</p> <p>Based on the fact that the part of downward radiance that depends on the optical properties of the aerosol in the atmosphere can be extracted from the measured sky radiance, a new scheme for <span class="hlt">retrieval</span> of the aerosol phase <span class="hlt">function</span> and the single-scattering albedo over the ocean is developed. This <span class="hlt">retrieval</span> algorithm is tested with simulations for several cases. It is found that the <span class="hlt">retrieved</span> aerosol phase <span class="hlt">function</span> and the single-scattering albedo are virtually error-free if the vertical structure of the atmosphere is known and if the sky radiance and the aerosol optical thickness can be measured accurately. The robustness of the algorithm in realistic situations, in which the measurements are contaminated by calibration errors or noise, is examined. It is found that the <span class="hlt">retrieved</span> value of omega(0) is usually in error by less than about 10 percent, and the phase <span class="hlt">function</span> is accurately <span class="hlt">retrieved</span> for theta less than about 90 deg. However, as the aerosol optical thickness becomes small, e.g., less than about 0.1, errors in the sky radiance measurement can lead to serious problems with the <span class="hlt">retrieval</span> algorithm, especially in the blue. The use of the <span class="hlt">retrieval</span> scheme should be limited to the red and near IR when the aerosol optical thickness is small.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790057372&hterms=Population+Dynamics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DPopulation%2BDynamics','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790057372&hterms=Population+Dynamics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DPopulation%2BDynamics"><span>Dynamic <span class="hlt">cross</span> <span class="hlt">correlation</span> studies of wave particle interactions in ULF phenomena</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mcpherron, R. L.</p> <p>1979-01-01</p> <p>Magnetic field observations made by satellites in the earth's magnetic field reveal a wide variety of ULF waves. These waves interact with the ambient particle populations in complex ways, causing modulation of the observed particle fluxes. This modulation is found to be a <span class="hlt">function</span> of species, pitch angle, energy and time. The characteristics of this modulation provide information concerning the wave mode and interaction process. One important characteristic of wave-particle interactions is the phase of the particle flux modulation relative to the magnetic field variations. To display this phase as a <span class="hlt">function</span> of time a dynamic cross spectrum program has been developed. The program produces contour maps in the frequency time plane of the <span class="hlt">cross</span> <span class="hlt">correlation</span> coefficient between any particle flux time series and the magnetic field vector. This program has been utilized in several studies of ULF wave-particle interactions at synchronous orbit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790057372&hterms=correlation+coefficient&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dcorrelation%2Bcoefficient','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790057372&hterms=correlation+coefficient&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dcorrelation%2Bcoefficient"><span>Dynamic <span class="hlt">cross</span> <span class="hlt">correlation</span> studies of wave particle interactions in ULF phenomena</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mcpherron, R. L.</p> <p>1979-01-01</p> <p>Magnetic field observations made by satellites in the earth's magnetic field reveal a wide variety of ULF waves. These waves interact with the ambient particle populations in complex ways, causing modulation of the observed particle fluxes. This modulation is found to be a <span class="hlt">function</span> of species, pitch angle, energy and time. The characteristics of this modulation provide information concerning the wave mode and interaction process. One important characteristic of wave-particle interactions is the phase of the particle flux modulation relative to the magnetic field variations. To display this phase as a <span class="hlt">function</span> of time a dynamic cross spectrum program has been developed. The program produces contour maps in the frequency time plane of the <span class="hlt">cross</span> <span class="hlt">correlation</span> coefficient between any particle flux time series and the magnetic field vector. This program has been utilized in several studies of ULF wave-particle interactions at synchronous orbit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhDT.......331C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhDT.......331C"><span>Smart Polyacrylonitrile (PAN) Nanofibers with Thermal Energy Storage and <span class="hlt">Retrieval</span> <span class="hlt">Functionality</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cherry, De'Andre James</p> <p></p> <p>Phase change materials (PCMs) are generally substances with a high heat of fusion in the process of solid to liquid phase change. The nature of PCMs make them efficient materials to store and <span class="hlt">retrieve</span> large amounts of thermal energy. Presently, high efficiency thermal energy storage/<span class="hlt">retrieval</span> in applications where flexibility and space saving are required, such as smart textiles, still remains as a challenge. In this study, lauric acid (LA) and myristic acid (MA) were combined to prepare a specific binary fatty acid eutectic (LA-MA) with a melting point near the operating body temperature of a human being and then encapsulated in polyacrylonitrile (PAN) nanofibers through the electrospinning technique. <span class="hlt">Functionalized</span> PCM-enhanced PAN nanofibers containing LA-MA at 30%, 50%, 70% and 100% of the weight of the PAN were successfully synthesized. The morphological structures and thermal energy storage capacity of the PCM-enhanced PAN nanofibers were characterized by electron microscopy (EM) and differential scanning calorimetry (DSC). The novel PCM-enhanced PAN nanofibers maintained their cylindrical fiber morphology after multiple heating-cooling cycles and retained their latent heat storage <span class="hlt">functionality</span>. Thus, it is envisioned that the prepared PCM-enhanced PAN nanofibers will find use in applications such as smart textiles where temperature regulation <span class="hlt">functionality</span> is required.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoJI.201.1383J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoJI.201.1383J"><span>Surface wave phase-velocity tomography based on multichannel <span class="hlt">cross-correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jin, Ge; Gaherty, James B.</p> <p>2015-06-01</p> <p>We have developed a new method to <span class="hlt">retrieve</span> seismic surface wave phase velocity using dense seismic arrays. The method measures phase variations between nearby stations based on waveform <span class="hlt">cross-correlation</span>. The coherence in waveforms between adjacent stations results in highly precise relative phase estimates. Frequency-dependent phase variations are then inverted for spatial variations in apparent phase velocity via the Eikonal equation. Frequency-dependent surface wave amplitudes measured on individual stations are used to correct the apparent phase velocity to account for multipathing via the Helmholtz equation. By using coherence and other data selection criteria, we construct an automated system that <span class="hlt">retrieves</span> structural phase-velocity maps directly from raw seismic waveforms for individual earthquakes without human intervention. The system is applied to broad-band seismic data from over 800 events recorded on EarthScope's USArray from 2006 to 2014, systematically building up Rayleigh-wave phase-velocity maps between the periods of 20 and 100 s for the entire continental United States. At the highest frequencies, the resulting maps are highly correlated with phase-velocity maps derived from ambient noise tomography. At all frequencies, we observe a significant contrast in Rayleigh-wave phase velocity between the tectonically active western US and the stable eastern US, with the phase velocity variations in the western US being 1-2 times greater. The Love wave phase-velocity maps are also calculated. We find that overtone contamination may produce systemic bias for the Love-wave phase-velocity measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..410..154M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..410..154M"><span>Multifractal detrended <span class="hlt">cross-correlation</span> analysis of the oil-dependent economies: Evidence from the West Texas intermediate crude oil and the GCC stock markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, Feng; Zhang, Qian; Peng, Chen; Wei, Yu</p> <p>2014-09-01</p> <p>In this paper, we firstly investigate the <span class="hlt">cross-correlations</span> between the crude oil market and the six GCC stock markets. Based on the analysis of the significant statistic Qcc(m) and the <span class="hlt">cross-correlation</span> coefficient, we find that the <span class="hlt">cross-correlations</span> between the crude oil market and the six GCC stock markets are all significant. Employing the method of the MF-DFA and MF-DXA, we further find that the auto-correlations of the crude oil market and the six GCC stock markets and <span class="hlt">cross-correlations</span> between them are all the multifractality. Moreover, using the multifractal spectrum, we can also verify the multifractal characteristics between the crude oil market and the six GCC stock markets. Furthermore, we use the penalized contrast <span class="hlt">function</span> to detect the structural break points of the WTI-Oil return series and its conditional volatility, and then discuss the <span class="hlt">cross-correlations</span> between the crude oil and the six GCC stock markets in the different phases according to these break points. At last, we employ the technique of the rolling window to investigate the dynamic of the scaling exponent Hxy(q). In addition, we explore the relationship between the <span class="hlt">cross-correlation</span> exponents Hxy(q) and the average scaling exponents [Hxx(q)+Hyy(q)]/2].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840026698','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840026698"><span>Ultrasonic velocity measurement using phase-slope <span class="hlt">cross-correlation</span> methods</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hull, D. R.; Kautz, H. E.; Vary, A.</p> <p>1984-01-01</p> <p>Computer implemented phase-slope and <span class="hlt">cross-correlation</span> methods are introduced for measuring time delays between pairs of broadband ultrasonic pulse-echo signals for determining velocity in engineering materials. The phase-slope and <span class="hlt">cross-correlation</span> methods are compared with the overlap method which is currently in wide use. Comparison of digital versions of the three methods shows similar results for most materials having low ultrasonic attenuation. However, the <span class="hlt">cross-correlation</span> method is preferred for highly attenuating materials. An analytical basis for the <span class="hlt">cross-correlation</span> method is presented. Examples are given for the three methods investigated to measure velocity in representative materials in the megahertz range.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..468...91R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..468...91R"><span>Detrended <span class="hlt">cross-correlation</span> analysis on RMB exchange rate and Hang Seng China Enterprises Index</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruan, Qingsong; Yang, Bingchan; Ma, Guofeng</p> <p>2017-02-01</p> <p>In this paper, we investigate the <span class="hlt">cross-correlations</span> between the Hang Seng China Enterprises Index and RMB exchange markets on the basis of a <span class="hlt">cross-correlation</span> statistic test and multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA). MF-DCCA has, at best, serious limitations for most of the signals describing complex natural processes and often indicates multifractal <span class="hlt">cross-correlations</span> when there are none. In order to prevent these false multifractal <span class="hlt">cross-correlations</span>, we apply MFCCA to verify the <span class="hlt">cross-correlations</span>. Qualitatively, we find that the return series of the Hang Seng China Enterprises Index and RMB exchange markets were, overall, significantly <span class="hlt">cross-correlated</span> based on the statistical analysis. Quantitatively, we find that the <span class="hlt">cross-correlations</span> between the stock index and RMB exchange markets were strongly multifractal, and the multifractal degree of the onshore RMB exchange markets was somewhat larger than the offshore RMB exchange markets. Moreover, we use the absolute return series to investigate and confirm the fact of multifractality. The results from the rolling windows show that the short-term <span class="hlt">cross-correlations</span> between volatility series remain high.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhyA..392.1172W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhyA..392.1172W"><span>Price-volume <span class="hlt">cross-correlation</span> analysis of CSI300 index futures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Dong-Hua; Suo, Yuan-Yuan; Yu, Xiao-Wen; Lei, Man</p> <p>2013-03-01</p> <p>We investigate the <span class="hlt">cross-correlation</span> between price returns and trading volumes for the China Securities Index 300 (CSI300) index futures, which are the only stock index futures traded on the China Financial Futures Exchange (CFFEX). The basic statistics suggest that distributions of these two time series are not normal but exhibit fat tails. Based on the detrended <span class="hlt">cross-correlation</span> analysis (DCCA), we obtain that returns and trading volumes are long-range <span class="hlt">cross-correlated</span>. The existence of multifractality in the <span class="hlt">cross-correlation</span> between returns and trading volumes has been proven with the multifractal detrended <span class="hlt">cross-correlation</span> analysis (MFDCCA) algorithm. The multifractal analysis also confirms that returns and trading volumes have different degrees of multifractality. We further perform a <span class="hlt">cross-correlation</span> statistic to verify whether the <span class="hlt">cross-correlation</span> significantly exists between returns and trading volumes for CSI300 index futures. In addition, results of the test for lead-lag effect demonstrate that contemporaneous <span class="hlt">cross-correlation</span> of return and trading volume series is stronger than <span class="hlt">cross-correlations</span> of leaded or lagged series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21946370','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21946370"><span>Evolution of genuine <span class="hlt">cross-correlation</span> strength of focal onset seizures.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Müller, Markus F; Baier, Gerold; Jiménez, Yurytzy López; Marín García, Arlex O; Rummel, Christian; Schindler, Kaspar</p> <p>2011-10-01</p> <p>To quantify the evolution of genuine zero-lag <span class="hlt">cross-correlations</span> of focal onset seizures, we apply a recently introduced multivariate measure to broad band and to narrow-band EEG data. For frequency components below 12.5 Hz, the strength of genuine <span class="hlt">cross-correlations</span> decreases significantly during the seizure and the immediate postseizure period, while higher frequency bands show a tendency of elevated <span class="hlt">cross-correlations</span> during the same period. We conclude that in terms of genuine zero-lag <span class="hlt">cross-correlations</span>, the electrical brain activity as assessed by scalp electrodes shows a significant spatial fragmentation, which might promote seizure offset.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhyA..391.3930L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhyA..391.3930L"><span><span class="hlt">Cross-correlations</span> between agricultural commodity futures markets in the US and China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Zhihui; Lu, Xinsheng</p> <p>2012-08-01</p> <p>This paper examines the <span class="hlt">cross-correlation</span> properties of agricultural futures markets between the US and China using a <span class="hlt">cross-correlation</span> statistic test and multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA). The results show that the <span class="hlt">cross-correlations</span> between the two geographically distant markets for four pairs of important agricultural commodities futures are significantly multifractal. By introducing the concept of a “crossover”, we find that the multifractality of <span class="hlt">cross-correlations</span> between the two markets is not long lasting. The <span class="hlt">cross-correlations</span> in the short term are more strongly multifractal, but they are weakly so in the long term. Moreover, <span class="hlt">cross-correlations</span> of small fluctuations are persistent and those of large fluctuations are anti-persistent in the short term while <span class="hlt">cross-correlations</span> of all kinds of fluctuations for soy bean and soy meal futures are persistent and for corn and wheat futures are anti-persistent in the long term. We also find that <span class="hlt">cross-correlation</span> exponents are less than the averaged generalized Hurst exponent when q<0 and more than the averaged generalized Hurst exponent when q>0 in the short term, while in the long term they are almost the same.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhyA..392.3715W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhyA..392.3715W"><span>Random matrix theory analysis of <span class="hlt">cross-correlations</span> in the US stock market: Evidence from Pearson’s correlation coefficient and detrended <span class="hlt">cross-correlation</span> coefficient</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Gang-Jin; Xie, Chi; Chen, Shou; Yang, Jiao-Jiao; Yang, Ming-Yan</p> <p>2013-09-01</p> <p>In this study, we first build two empirical <span class="hlt">cross-correlation</span> matrices in the US stock market by two different methods, namely the Pearson’s correlation coefficient and the detrended <span class="hlt">cross-correlation</span> coefficient (DCCA coefficient). Then, combining the two matrices with the method of random matrix theory (RMT), we mainly investigate the statistical properties of <span class="hlt">cross-correlations</span> in the US stock market. We choose the daily closing prices of 462 constituent stocks of S&P 500 index as the research objects and select the sample data from January 3, 2005 to August 31, 2012. In the empirical analysis, we examine the statistical properties of <span class="hlt">cross-correlation</span> coefficients, the distribution of eigenvalues, the distribution of eigenvector components, and the inverse participation ratio. From the two methods, we find some new results of the <span class="hlt">cross-correlations</span> in the US stock market in our study, which are different from the conclusions reached by previous studies. The empirical <span class="hlt">cross-correlation</span> matrices constructed by the DCCA coefficient show several interesting properties at different time scales in the US stock market, which are useful to the risk management and optimal portfolio selection, especially to the diversity of the asset portfolio. It will be an interesting and meaningful work to find the theoretical eigenvalue distribution of a completely random matrix R for the DCCA coefficient because it does not obey the Marčenko-Pastur distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997JMagR.127....1D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997JMagR.127....1D"><span>Measurement of Homonuclear <span class="hlt">Cross-Correlation</span> Cross-Relaxation Rates along an Effective Field: Application to Dipole Dipole <span class="hlt">Cross-Correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Desvaux, Hervé</p> <p>1997-07-01</p> <p>We describe three new schemes to explore homonuclear <span class="hlt">cross-correlation</span> contributions to relaxation along an effective field tilted by an angle θ from the static magnetic field direction. Their key feature is to detect, during the evolution timet1, multiquantum transverse coherences whose frequencies are characteristic of the multispin order produced by <span class="hlt">cross-correlation</span> processes. This makes it possible to obtain in-phase magnetization in both dimensions. The three schemes correspond to the combination of two evolutions due either to staticJcoupling in the transverse plane or to <span class="hlt">cross-correlation</span> cross-relaxation along an effective field. This combination allows the conversion of one-spin order into multispin order and the reverse. If only <span class="hlt">cross-correlation</span> cross-relaxation transfers are involved, there is no restriction on the coupling network. The quantitative exploitation of the results to obtain structural information from <span class="hlt">cross-correlation</span>-induced relaxation rates requires a normalization coefficient which is provided by the simultaneous monitoring of one-spin coherence. These ideas have been tested experimentally in the case of dipole-dipole <span class="hlt">cross-correlation</span> on a sample of cyclosporin. Buildup curves at various angles θ are described which yield information on the internal dynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21944154','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21944154"><span><span class="hlt">Functional</span> brain activation during <span class="hlt">retrieval</span> of visceral pain-conditioned passive avoidance in the rat.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Zhuo; Bradesi, Sylvie; Charles, Jonathan R; Pang, Raina D; Maarek, Jean-Michel I; Mayer, Emeran A; Holschneider, Daniel P</p> <p>2011-12-01</p> <p>This study assessed <span class="hlt">functional</span> brain activation in rats during expectation of visceral pain. Male rats were trained in step-down passive avoidance (PA) for 2 days. Upon stepping down from a platform, conditioned animals received noxious colorectal distension delivered through a colorectal balloon, whereas the balloon in control rats remained uninflated. On day 3, PA behavior was assessed while [(14)C]-iodoantipyrine was infused intravenously, followed by immediate euthanasia. Regional cerebral blood flow-related tissue radioactivity (rCBF) was analyzed by statistical parametric mapping using 3-dimensional brains reconstructed from autoradiographic brain slice images. Associated with <span class="hlt">retrieved</span> PA behavior, conditioned rats compared with control subjects showed increases in rCBF in sensory (anterior insula, somatosensory cortex), limbic/paralimbic regions (anterior cingulate, prelimbic cortex, amygdala), all regions previously reported to show activation during acute visceral pain. Increases in rCBF were also noted in the dorsal hippocampus, nucleus accumbens, and caudate putamen, regions associated with <span class="hlt">retrieval</span> of PA. Organization of the underlying brain network was further delineated by <span class="hlt">functional</span> connectivity analysis. This revealed in conditioned rats a strongly and positively connected corticostriatal cluster (cingulate, prelimbic cortex, caudate putamen). The amygdala and cerebellar hemispheres formed another positively connected cluster, which was negatively connected with the corticostriatal cluster, suggesting corticolimbic modulation. Prelimbic cortex, nucleus accumbens, and anterior insula emerged in conditioned animals as hubs. Our results show that during <span class="hlt">retrieval</span> of PA, brain areas implicated in PA expression as well as those implicated in acute visceral pain processing were recruited, in line with findings from human brain imaging studies on pain expectation. Copyright © 2011 International Association for the Study of Pain. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMIN21A3700G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMIN21A3700G"><span>Big Data Solution for CTBT Monitoring Using Global <span class="hlt">Cross</span> <span class="hlt">Correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gaillard, P.; Bobrov, D.; Dupont, A.; Grenouille, A.; Kitov, I. O.; Rozhkov, M.</p> <p>2014-12-01</p> <p>Due to the mismatch between data volume and the performance of the Information Technology infrastructure used in seismic data centers, it becomes more and more difficult to process all the data with traditional applications in a reasonable elapsed time. To fulfill their missions, the International Data Centre of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO/IDC) and the Département Analyse Surveillance Environnement of Commissariat à l'Energie atomique et aux énergies alternatives (CEA/DASE) collect, process and produce complex data sets whose volume is growing exponentially. In the medium term, computer architectures, data management systems and application algorithms will require fundamental changes to meet the needs. This problem is well known and identified as a "Big Data" challenge. To tackle this major task, the CEA/DASE takes part during two years to the "DataScale" project. Started in September 2013, DataScale gathers a large set of partners (research laboratories, SMEs and big companies). The common objective is to design efficient solutions using the synergy between Big Data solutions and the High Performance Computing (HPC). The project will evaluate the relevance of these technological solutions by implementing a demonstrator for seismic event detections thanks to massive waveform correlations. The IDC has developed an expertise on such techniques leading to an algorithm called "Master Event" and provides a high-quality dataset for an extensive <span class="hlt">cross</span> <span class="hlt">correlation</span> study. The objective of the project is to enhance the Master Event algorithm and to reanalyze 10 years of waveform data from the International Monitoring System (IMS) network thanks to a dedicated HPC infrastructure operated by the "Centre de Calcul Recherche et Technologie" at the CEA of Bruyères-le-Châtel. The dataset used for the demonstrator includes more than 300,000 seismic events, tens of millions of raw detections and more than 30 terabytes of continuous seismic data</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020023521&hterms=error+measurements+experimental&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Derror%2Bmeasurements%2Bexperimental','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020023521&hterms=error+measurements+experimental&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Derror%2Bmeasurements%2Bexperimental"><span>Columnar Aerosol Single-Scattering Albedo and Phase <span class="hlt">Function</span> <span class="hlt">Retrieved</span> from Sky Radiance Over the Ocean: Measurements of African Dust</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cattrall, Christopher; Carder, Kendall L.; Gordon, Howard R.</p> <p>2001-01-01</p> <p>The single-scattering albedo and phase <span class="hlt">function</span> of African mineral dust are <span class="hlt">retrieved</span> from ground-based measurements of sky radiance collected in the Florida Keys. The <span class="hlt">retrieval</span> algorithm employs the radiative transfer equation to solve by iteration for these two properties which best reproduce the observed sky radiance using an assumed aerosol vertical structure and measured aerosol optical depth. Thus, no assumptions regarding particle size, shape, or composition are required. The single-scattering albedo, presented at fourteen wavelengths between 380 and 870 nm, displays a spectral shape expected of iron-bearing minerals but is much higher than current dust models allow. This indicates the absorption of light by mineral dust is significantly overestimated in climate studies. Uncertainty in the <span class="hlt">retrieved</span> albedo is less than 0.02 due to the small uncertainty in the solar-reflectance-based calibration (12.2%) method employed. The phase <span class="hlt">function</span> <span class="hlt">retrieved</span> at 860 nm is very robust under simulations of expected experimental errors, indicating <span class="hlt">retrieved</span> phase <span class="hlt">functions</span> at this wavelength may be confidently used to describe aerosol scattering characteristics. The phase <span class="hlt">function</span> <span class="hlt">retrieved</span> at 443 nm is very sensitive to expected experimental errors and should not be used to describe aerosol scattering. Radiative forcing by aerosol is the greatest source of uncertainty in current climate models. These results will help reduce uncertainty in the absorption of light by mineral dust. Assessment of the radiative impact of aerosol species is a key component to NASA's Earth System Enterprise.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24639328','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24639328"><span>Altered neural <span class="hlt">function</span> during episodic memory encoding and <span class="hlt">retrieval</span> in major depression.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dietsche, Bruno; Backes, Heidelore; Stratmann, Mirjam; Konrad, Carsten; Kircher, Tilo; Krug, Axel</p> <p>2014-09-01</p> <p>Memory impairments are common in major depression. Neural processing during non-emotional episodic memory in depressed patients has only sparsely been investigated, since the majority of studies have focused on emotional stimuli. The aim of this study was to explore neural correlates of episodic memory in depressive patients and to assess brain regions related to subsequent memory performance. Forty-six participants (23 depressed patients) performed a non-emotional episodic memory encoding and <span class="hlt">retrieval</span> task while brain activation was measured with <span class="hlt">functional</span> magnetic resonance imaging. Patients with depression showed decreased activation in the right prefrontal cortex and right cingulate cortex during memory encoding, but increased activation in the right inferior frontal gyrus (IFG) during recognition memory. While a strong association between hippocampal and parahippocampal activation during memory encoding with subsequent memory performance became evident in healthy controls, this relationship was absent in patients with depression. Taken together, these findings demonstrate that memory related brain regions are affected in their appropriate <span class="hlt">functioning</span> during memory encoding in depressed patients. Therefore, patients with depression may rely to a greater degree on other brain regions such as the IFG during episodic memory <span class="hlt">retrieval</span>. Copyright © 2014 Wiley Periodicals, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3615453','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3615453"><span>Robust spectral-domain optical coherence tomography speckle model and its <span class="hlt">cross-correlation</span> coefficient analysis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Liu, Xuan; Ramella-Roman, Jessica C.; Huang, Yong; Guo, Yuan; Kang, Jin U.</p> <p>2013-01-01</p> <p>In this study, we proposed a generic speckle simulation for optical coherence tomography (OCT) signal, by convolving the point spread <span class="hlt">function</span> (PSF) of the OCT system with the numerically synthesized random sample field. We validated our model and used the simulation method to study the statistical properties of <span class="hlt">cross-correlation</span> coefficients (XCC) between Ascans which have been recently applied in transverse motion analysis by our group. The results of simulation show that over sampling is essential for accurate motion tracking; exponential decay of OCT signal leads to an under estimate of motion which can be corrected; lateral heterogeneity of sample leads to an over estimate of motion for a few pixels corresponding to the structural boundary. PMID:23456001</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23456001','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23456001"><span>Robust spectral-domain optical coherence tomography speckle model and its <span class="hlt">cross-correlation</span> coefficient analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Xuan; Ramella-Roman, Jessica C; Huang, Yong; Guo, Yuan; Kang, Jin U</p> <p>2013-01-01</p> <p>In this study, we propose a generic speckle simulation for optical coherence tomography (OCT) signal, by convolving the point-spread <span class="hlt">function</span> (PSF) of the OCT system with the numerically synthesized random sample field. We validate our model and use the simulation method to study the statistical properties of <span class="hlt">cross-correlation</span> coefficients between A-scans, which have been recently applied in transverse motion analysis by our group. The results of simulation show that oversampling is essential for accurate motion tracking; exponential decay of OCT signal leads to an underestimate of motion that can be corrected; lateral heterogeneity of sample leads to an overestimate of motion for a few pixels corresponding to the structural boundary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..441...32L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..441...32L"><span>Transitions induced by <span class="hlt">cross-correlated</span> bounded noises and time delay in a genotype selection model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Pei; Ning, Li Juan</p> <p>2016-01-01</p> <p>We present a numerical investigation of occurrence of transitions in a genotype selection model with time delay, where two bounded noises are <span class="hlt">cross-correlated</span>. Stationary probability distribution (SPD) <span class="hlt">function</span> is obtained. It is found that: the multiplicative bounded noise can facilitate the gene separation and it plays a constructive role in the genetic selection progress, while the additive bounded noise suppresses the gene separation. The strong correlation between noises gives a big chance to one type haploid out of the group. Besides, what is more interesting is that the correlation time τ can induce a new transitions (i.e., the curve of the SPD changes from unimodal to bimodal, and then to four peaks as the correlation time τ increases).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSH31C2429H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSH31C2429H"><span>Multi-scale Analysis of DSCOVR Data Using Wavelet <span class="hlt">Cross</span> <span class="hlt">Correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hegedus, A. M.; Kasper, J. C.; Stevens, M. L.; Alterman, B. L.; Case, A. W.; Szabo, A.; Koval, A.</p> <p>2015-12-01</p> <p>The Deep Space Climate Observatory (DSCOVR), launched February 11th 2015, makes the fastest combined measurements of solar wind magnetic field vectors and ion velocity distribution <span class="hlt">functions</span> ever. These data allow us to search for correlation between ion and magnetic field fluctuations at kinetic ion scales for the first time. We present first results of a wavelet correlation analysis, which allows us to search for wave-particle interactions while accounting for different sampling cadences and data gaps. Using different wavelet algorithms we circumvent these issues and decompose the covariance and correlation between these two data streams on a scale by scale basis. We then generalize these quantities to wavelet <span class="hlt">cross-correlation</span> and cross-covariance to identify interactions between charged particles and magnetic fields on kinetic scales. The techniques developed in this work will be directly applicable to plasma and magnetic field observations in the corona on the upcoming Solar Probe Plus mission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S51A4386G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S51A4386G"><span>Comparison of a Waveform <span class="hlt">Cross</span> <span class="hlt">Correlation</span> Detection Method to a Traditional STA/LTA Picker: Application to the Crooked Lake Sequence Near Fox Creek, Alberta</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Greig, D. W.; Spriggs, N.</p> <p>2014-12-01</p> <p>Waveform <span class="hlt">cross</span> <span class="hlt">correlation</span>, or template matching as it is sometimes called, has long been known to be an effective method for finding occurrences of a known repeating signal within a waveform. Because seismic signals are rarely known a priori, waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> is not often used as a detection method for seismic networks. However, past studies (e.g. Gibbons and Ringdal, 2006) have shown that <span class="hlt">cross</span> <span class="hlt">correlation</span> can be effective in identifying events with similar locations and focal mechanisms (and thus waveforms) to a pre-existing template. Because induced seismicity often satisfies these requirements the method is well-suited to induced seismicity monitoring. We apply the method of waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> to a sequence of events between Nov. 29, 2013 and Dec. 13, 2013 occurring at Crooked Lake near Fox Creek, Alberta. These events are believed to be attributable to injection activities in the area. A total of 24 events were detected using traditional STA/LTA triggering methods. The largest event, measured at local magnitude 3.9, is used as a template to identify other events. We compare the effectiveness of the traditional STA/LTA detection method to the <span class="hlt">cross</span> <span class="hlt">correlation</span> technique. With a modest correlation threshold we identify all 24 of the original events and an additional 89 new events for a total of 113 events identified by waveform <span class="hlt">cross</span> <span class="hlt">correlation</span>. We estimate the magnitude of completeness using the maximum curvature method (Wiemer and Wyss, 2000) and compare the result for the STA/LTA catalogue and the <span class="hlt">cross</span> <span class="hlt">correlation</span> catalogue. We find that the magnitude of completeness is about 0.8 magnitude units lower for the <span class="hlt">cross</span> <span class="hlt">correlation</span> catalogue. We explore the possibility of determining a probability density <span class="hlt">function</span> to describe the values of observed correlation between a template and a seismic signal and reconcile theoretical expectations with empirical data. We further suggest a trigger threshold for <span class="hlt">cross</span> <span class="hlt">correlation</span> detection algorithms</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OptLE..86...44C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OptLE..86...44C"><span>Investigation of measurement sensitivities in <span class="hlt">cross-correlation</span> Doppler global velocimetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cadel, Daniel R.; Lowe, K. Todd</p> <p>2016-11-01</p> <p><span class="hlt">Cross-correlation</span> Doppler global velocimetry (CC-DGV) is a flow measurement technique based on the estimation of Doppler frequency shift of scattered light by means of <span class="hlt">cross-correlating</span> two filtered intensity signals. The signal characteristics of CC-DGV result in fundamental limits for estimation variance as well as the possibility for estimator bias. The current study assesses these aspects theoretically and via Monte Carlo signal simulations. A signal model is developed using canonical numerical <span class="hlt">functions</span> for the iodine absorption cell and incorporating Poisson and Gaussian signal noise models. Along with consideration of the analytical form of the Cramér-Rao lower bound, best practices for system settings are discussed. The CC-DGV signal processing routine is then assessed by a series of Monte Carlo simulations studying the effect of temperature mismatch between flow signal and reference detector cells, velocity magnitude, and discretization error in the frequency modulation. A measurement bias was observed; the magnitude of the bias is a weak <span class="hlt">function</span> of the cell temperature mismatch, but it is independent of the flow velocity magnitude. The measurement variance was found to approach the Cramér-Rao lower bound for optimized conditions. A cyclical bias error resulting from the discrete nature of the laser frequency sweep is also observed with maximum errors of ± 1.0 % of the laser frequency scan step size, corresponding to peak errors of ± 0.61 m s-1 for typical settings. Overall, the signal estimator is found to perform best for matched cell temperatures, small frequency step size, and high velocity regimes, where the relative bias errors are collectively minimized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhyA..391.4855C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhyA..391.4855C"><span>Multifractal detrended <span class="hlt">cross-correlations</span> between the Chinese exchange market and stock market</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cao, Guangxi; Xu, Longbing; Cao, Jie</p> <p>2012-10-01</p> <p>Based on the daily price data of the Chinese Yuan (RMB)/US dollar exchange rate and the Shanghai Stock Composite Index, we conducted an empirical analysis of the <span class="hlt">cross-correlations</span> between the Chinese exchange market and stock market using the multifractal <span class="hlt">cross-correlation</span> analysis method. The results demonstrate the overall significance of the <span class="hlt">cross-correlation</span> based on the analysis of a statistic. Multifractality exists in <span class="hlt">cross-correlations</span>, and the <span class="hlt">cross-correlated</span> behavior of small fluctuations is more persistent than that of large fluctuations. Moreover, using the rolling windows method, we find that the <span class="hlt">cross-correlations</span> between the Chinese exchange market and stock market vary with time and are especially sensitive to the reform of the RMB exchange rate regime. The previous reduction in the flexibility of the RMB exchange rate in July 2008 strengthened the persistence of <span class="hlt">cross-correlations</span> and decreased the degree of multifractality, whereas the enhancement of the flexibility of the RMB exchange rate in June 2010 weakened the persistence of <span class="hlt">cross-correlations</span> and increased the multifractality. Finally, several relevant discussions are provided to verify the robustness of our empirical analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..451...10R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..451...10R"><span><span class="hlt">Cross-correlations</span> between price and volume in Chinese gold markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruan, Qingsong; Jiang, Wei; Ma, Guofeng</p> <p>2016-06-01</p> <p>We apply the multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA) method to investigate the <span class="hlt">cross-correlation</span> behaviors between price and volume in Chinese gold spot and futures markets. Qualitatively, we find that the price and volume series are significantly <span class="hlt">cross-correlated</span> using the <span class="hlt">cross-correlation</span> test statistics Qcc(m) and the ρDCCA coefficients. Quantitatively, by employing the MF-DCCA analysis, we find that there is a power-law <span class="hlt">cross-correlation</span> and significant multifractal features between price and volume in gold spot and futures markets. Furthermore, by comparing the multifractality of the original series to the shuffled and surrogated series, we find that, for the gold spot market, the main contribution of multifractality is fat-tail distribution; for the gold futures market, both long-range correlations and fat-tail distributions play important roles in the contribution of multifractality. Finally, by employing the method of rolling windows, we undertake further investigation into the time-varying features of the <span class="hlt">cross-correlations</span> between price and volume. We find that for both spot and futures markets, the <span class="hlt">cross-correlations</span> are anti-persistent in general. In the short term, the <span class="hlt">cross-correlation</span> shows obvious fluctuations due to exogenous shocks while, in the long term, the relationship tends to be at a metastable level due to the dynamic mechanism.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..453..131L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..453..131L"><span><span class="hlt">Cross-correlations</span> between crude oil and exchange markets for selected oil rich economies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Jianfeng; Lu, Xinsheng; Zhou, Ying</p> <p>2016-07-01</p> <p>Using multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA), this paper studies the <span class="hlt">cross-correlation</span> behavior between crude oil market and five selected exchange rate markets. The dataset covers the period of January 1,1996-December 31,2014, and contains 4,633 observations for each of the series, including daily closing prices of crude oil, Australian Dollars, Canadian Dollars, Mexican Pesos, Russian Rubles, and South African Rand. Our empirical results obtained from <span class="hlt">cross-correlation</span> statistic and <span class="hlt">cross-correlation</span> coefficient have confirmed the existence of <span class="hlt">cross-correlations</span>, and the MF-DCCA results have demonstrated a strong multifractality between <span class="hlt">cross-correlated</span> crude oil market and exchange rate markets in both short term and long term. Using rolling window analysis, we have also found the persistent <span class="hlt">cross-correlations</span> between the exchange rates and crude oil returns, and the <span class="hlt">cross-correlation</span> scaling exponents exhibit volatility during some time periods due to its sensitivity to sudden events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvD..91j2005W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvD..91j2005W"><span>Model-based <span class="hlt">cross-correlation</span> search for gravitational waves from Scorpius X-1</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Whelan, John T.; Sundaresan, Santosh; Zhang, Yuanhao; Peiris, Prabath</p> <p>2015-05-01</p> <p>We consider the <span class="hlt">cross-correlation</span> search for periodic gravitational waves and its potential application to the low-mass x-ray binary Sco X-1. This method coherently combines data not only from different detectors at the same time, but also data taken at different times from the same or different detectors. By adjusting the maximum allowed time offset between a pair of data segments to be coherently combined, one can tune the method to trade off sensitivity and computing costs. In particular, the detectable signal amplitude scales as the inverse fourth root of this coherence time. The improvement in amplitude sensitivity for a search with a maximum time offset of one hour, compared with a directed stochastic background search with 0.25-Hz-wide bins, is about a factor of 5.4. We show that a search of one year of data from the Advanced LIGO and Advanced Virgo detectors with a coherence time of one hour would be able to detect gravitational waves from Sco X-1 at the level predicted by torque balance over a range of signal frequencies from 30 to 300 Hz; if the coherence time could be increased to ten hours, the range would be 20 to 500 Hz. In addition, we consider several technical aspects of the <span class="hlt">cross-correlation</span> method: We quantify the effects of spectral leakage and show that nearly rectangular windows still lead to the most sensitive search. We produce an explicit parameter-space metric for the <span class="hlt">cross-correlation</span> search, in general, and as applied to a neutron star in a circular binary system. We consider the effects of using a signal template averaged over unknown amplitude parameters: The quantity to which the search is sensitive is a given <span class="hlt">function</span> of the intrinsic signal amplitude and the inclination of the neutron-star rotation axis to the line of sight, and the peak of the expected detection statistic is systematically offset from the true signal parameters. Finally, we describe the potential loss of signal-to-noise ratio due to unmodeled effects such as signal</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.465.4118J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.465.4118J"><span>2dFLenS and KiDS: determining source redshift distributions with <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Johnson, Andrew; Blake, Chris; Amon, Alexandra; Erben, Thomas; Glazebrook, Karl; Harnois-Deraps, Joachim; Heymans, Catherine; Hildebrandt, Hendrik; Joudaki, Shahab; Klaes, Dominik; Kuijken, Konrad; Lidman, Chris; Marin, Felipe A.; McFarland, John; Morrison, Christopher B.; Parkinson, David; Poole, Gregory B.; Radovich, Mario; Wolf, Christian</p> <p>2017-03-01</p> <p>We develop a statistical estimator to infer the redshift probability distribution of a photometric sample of galaxies from its angular <span class="hlt">cross-correlation</span> in redshift bins with an overlapping spectroscopic sample. This estimator is a minimum-variance weighted quadratic <span class="hlt">function</span> of the data: a quadratic estimator. This extends and modifies the methodology presented by McQuinn & White. The derived source redshift distribution is degenerate with the source galaxy bias, which must be constrained via additional assumptions. We apply this estimator to constrain source galaxy redshift distributions in the Kilo-Degree imaging survey through <span class="hlt">cross-correlation</span> with the spectroscopic 2-degree Field Lensing Survey, presenting results first as a binned step-wise distribution in the range z < 0.8, and then building a continuous distribution using a Gaussian process model. We demonstrate the robustness of our methodology using mock catalogues constructed from N-body simulations, and comparisons with other techniques for inferring the redshift distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22306215','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22306215"><span>A 32-channel photon counting module with embedded auto/<span class="hlt">cross-correlators</span> for real-time parallel fluorescence correlation spectroscopy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gong, S.; Labanca, I.; Rech, I.; Ghioni, M.</p> <p>2014-10-15</p> <p>Fluorescence correlation spectroscopy (FCS) is a well-established technique to study binding interactions or the diffusion of fluorescently labeled biomolecules in vitro and in vivo. Fast FCS experiments require parallel data acquisition and analysis which can be achieved by exploiting a multi-channel Single Photon Avalanche Diode (SPAD) array and a corresponding multi-input correlator. This paper reports a 32-channel FPGA based correlator able to perform 32 auto/<span class="hlt">cross-correlations</span> simultaneously over a lag-time ranging from 10 ns up to 150 ms. The correlator is included in a 32 × 1 SPAD array module, providing a compact and flexible instrument for high throughput FCS experiments. However, some inherent features of SPAD arrays, namely afterpulsing and optical crosstalk effects, may introduce distortions in the measurement of auto- and <span class="hlt">cross-correlation</span> <span class="hlt">functions</span>. We investigated these limitations to assess their impact on the module and evaluate possible workarounds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014RScI...85j3101G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014RScI...85j3101G"><span>A 32-channel photon counting module with embedded auto/<span class="hlt">cross-correlators</span> for real-time parallel fluorescence correlation spectroscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gong, S.; Labanca, I.; Rech, I.; Ghioni, M.</p> <p>2014-10-01</p> <p>Fluorescence correlation spectroscopy (FCS) is a well-established technique to study binding interactions or the diffusion of fluorescently labeled biomolecules in vitro and in vivo. Fast FCS experiments require parallel data acquisition and analysis which can be achieved by exploiting a multi-channel Single Photon Avalanche Diode (SPAD) array and a corresponding multi-input correlator. This paper reports a 32-channel FPGA based correlator able to perform 32 auto/<span class="hlt">cross-correlations</span> simultaneously over a lag-time ranging from 10 ns up to 150 ms. The correlator is included in a 32 × 1 SPAD array module, providing a compact and flexible instrument for high throughput FCS experiments. However, some inherent features of SPAD arrays, namely afterpulsing and optical crosstalk effects, may introduce distortions in the measurement of auto- and <span class="hlt">cross-correlation</span> <span class="hlt">functions</span>. We investigated these limitations to assess their impact on the module and evaluate possible workarounds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4185060','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4185060"><span>A 32-channel photon counting module with embedded auto/<span class="hlt">cross-correlators</span> for real-time parallel fluorescence correlation spectroscopy</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gong, S.; Labanca, I.; Rech, I.; Ghioni, M.</p> <p>2014-01-01</p> <p>Fluorescence correlation spectroscopy (FCS) is a well-established technique to study binding interactions or the diffusion of fluorescently labeled biomolecules in vitro and in vivo. Fast FCS experiments require parallel data acquisition and analysis which can be achieved by exploiting a multi-channel Single Photon Avalanche Diode (SPAD) array and a corresponding multi-input correlator. This paper reports a 32-channel FPGA based correlator able to perform 32 auto/<span class="hlt">cross-correlations</span> simultaneously over a lag-time ranging from 10 ns up to 150 ms. The correlator is included in a 32 × 1 SPAD array module, providing a compact and flexible instrument for high throughput FCS experiments. However, some inherent features of SPAD arrays, namely afterpulsing and optical crosstalk effects, may introduce distortions in the measurement of auto- and <span class="hlt">cross-correlation</span> <span class="hlt">functions</span>. We investigated these limitations to assess their impact on the module and evaluate possible workarounds. PMID:25362365</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23556966','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23556966"><span><span class="hlt">Cross-correlation</span> detection and analysis for California's electricity market based on analogous multifractal analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Fang; Liao, Gui-ping; Li, Jian-hui; Zou, Rui-biao; Shi, Wen</p> <p>2013-03-01</p> <p>A novel method, which we called the analogous multifractal <span class="hlt">cross-correlation</span> analysis, is proposed in this paper to study the multifractal behavior in the power-law <span class="hlt">cross-correlation</span> between price and load in California electricity market. In addition, a statistic ρAMF-XA, which we call the analogous multifractal <span class="hlt">cross-correlation</span> coefficient, is defined to test whether the <span class="hlt">cross-correlation</span> between two given signals is genuine or not. Our analysis finds that both the price and load time series in California electricity market express multifractal nature. While, as indicated by the ρAMF-XA statistical test, there is a huge difference in the <span class="hlt">cross-correlation</span> behavior between the years 1999 and 2000 in California electricity markets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013Chaos..23a3129W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013Chaos..23a3129W"><span><span class="hlt">Cross-correlation</span> detection and analysis for California's electricity market based on analogous multifractal analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Fang; Liao, Gui-ping; Li, Jian-hui; Zou, Rui-biao; Shi, Wen</p> <p>2013-03-01</p> <p>A novel method, which we called the analogous multifractal <span class="hlt">cross-correlation</span> analysis, is proposed in this paper to study the multifractal behavior in the power-law <span class="hlt">cross-correlation</span> between price and load in California electricity market. In addition, a statistic ρAMF -XA, which we call the analogous multifractal <span class="hlt">cross-correlation</span> coefficient, is defined to test whether the <span class="hlt">cross-correlation</span> between two given signals is genuine or not. Our analysis finds that both the price and load time series in California electricity market express multifractal nature. While, as indicated by the ρAMF -XA statistical test, there is a huge difference in the <span class="hlt">cross-correlation</span> behavior between the years 1999 and 2000 in California electricity markets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009SPIE.7283E..0VP','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009SPIE.7283E..0VP"><span>Interfaces roughness <span class="hlt">cross</span> <span class="hlt">correlation</span> properties and light scattering of optical thin films</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pan, Yong-qiang; Wu, Zhen-sen; Hang, Ling-xia</p> <p>2009-05-01</p> <p>In order to study optical thin films interfaces roughness <span class="hlt">cross</span> <span class="hlt">correlation</span> properties and light scattering, theoretical models of optical thin films interfaces roughness light scattering are concisely presented. Furthermore, influence of interfaces roughness <span class="hlt">cross-correlation</span> properties to light scattering was analyzed by total backscattering. Moreover, TiO2 single optical films thickness, substrate roughness of K9 glass and ion beam assisted deposition (IBAD) technique effect on interface roughness <span class="hlt">cross</span> <span class="hlt">correlation</span> properties were studied by experiments, respectively. The results showed that theoretical results obtained by integrating vector light scattering were agreed well with experimental results. The interfaces roughness <span class="hlt">cross-correlation</span> decrease with the increase of films thickness or with the decrease of substrates roughness. When ion beam assisted deposition was used, a high degree of <span class="hlt">cross-correlated</span> can be obtained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19740014537&hterms=jet+engine&qs=N%3D0%26Ntk%3DTitle%26Ntx%3Dmode%2Bmatchall%26Ntt%3Djet%2Bengine','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19740014537&hterms=jet+engine&qs=N%3D0%26Ntk%3DTitle%26Ntx%3Dmode%2Bmatchall%26Ntt%3Djet%2Bengine"><span>Use of <span class="hlt">cross-correlation</span> measurements to investigate noise generating regions of a real jet engine and a model jet</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Meecham, W. C.; Hurdle, P. M.</p> <p>1974-01-01</p> <p><span class="hlt">Cross-correlations</span> are reported of the jet static pressure fluctuations (as measured with a B and K microphone fitted with a nose cone), with the far-field radiated sound pressure. These measurements were made for various probe positions and a large number of far-field positions (at various angles). In addition, the tests were run for a number of different jet exit velocities. The measured, normalized <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> vary between 0.004 and 0.155. These values depend upon the angular position of the far-field microphone, the jet exit Mach number, and the position of the probe. In addition, the <span class="hlt">cross-correlation</span> technique was employed to study the symmetry of the far-field radiated sound about the jet axis. Third-octave analyses of both the probe signal and the far-field radiated sound were made. This is the first time correlation measurements have been made on a jet engine. In addition, a report is given on an extensive noise survey of a model jet. The correlations are related to sound source <span class="hlt">functions</span> and jet source regions are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24946713','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24946713"><span>Electron multiplying charge-coupled device-based fluorescence <span class="hlt">cross-correlation</span> spectroscopy for blood velocimetry on zebrafish embryos.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pozzi, Paolo; Sironi, Laura; D'Alfonso, Laura; Bouzin, Margaux; Collini, Maddalena; Chirico, Giuseppe; Pallavicini, Piersandro; Cotelli, Franco; Foglia, Efrem A</p> <p>2014-06-01</p> <p>Biomedical issues in vasculogenesis and cardiogenesis require methods to follow hemodynamics with high spatial (micrometers) and time (milliseconds) resolution. At the same time, we need to follow relevant morphogenetic processes on large fields of view. Fluorescence <span class="hlt">cross-correlation</span> spectroscopy coupled to scanning or wide-field microscopy meets these needs but has limited flexibility in the excitation pattern. To overcome this limitation, we develop here a two-photon two-spots setup coupled to an all-reflective near-infrared (NIR) optimized scanning system and to an electron multiplying charge-coupled device. Two NIR laser spots are spaced at adjustable micron-size distances (1 to 50 μm) by means of a Twyman-Green interferometer and repeatedly scanned on the sample, allowing acquisition of information on flows at 4 ms-3 μm time-space resolution in parallel on an extended field of view. We analyze the effect of nonhomogeneous and variable flow on the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> by numerical simulations and show exemplary application of this setup in studies of blood flow in zebrafish embryos in vivo. By coupling the interferometer with the scanning mirrors and by computing the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> of fluorescent red blood cells, we are able to map speed patterns in embryos' vessels.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JBO....19f7007P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JBO....19f7007P"><span>Electron multiplying charge-coupled device-based fluorescence <span class="hlt">cross-correlation</span> spectroscopy for blood velocimetry on zebrafish embryos</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pozzi, Paolo; Sironi, Laura; D'Alfonso, Laura; Bouzin, Margaux; Collini, Maddalena; Chirico, Giuseppe; Pallavicini, Piersandro; Cotelli, Franco; Foglia, Efrem A.</p> <p>2014-06-01</p> <p>Biomedical issues in vasculogenesis and cardiogenesis require methods to follow hemodynamics with high spatial (micrometers) and time (milliseconds) resolution. At the same time, we need to follow relevant morphogenetic processes on large fields of view. Fluorescence <span class="hlt">cross-correlation</span> spectroscopy coupled to scanning or wide-field microscopy meets these needs but has limited flexibility in the excitation pattern. To overcome this limitation, we develop here a two-photon two-spots setup coupled to an all-reflective near-infrared (NIR) optimized scanning system and to an electron multiplying charge-coupled device. Two NIR laser spots are spaced at adjustable micron-size distances (1 to 50 μm) by means of a Twyman-Green interferometer and repeatedly scanned on the sample, allowing acquisition of information on flows at 4 ms-3 μm time-space resolution in parallel on an extended field of view. We analyze the effect of nonhomogeneous and variable flow on the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> by numerical simulations and show exemplary application of this setup in studies of blood flow in zebrafish embryos in vivo. By coupling the interferometer with the scanning mirrors and by computing the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> of fluorescent red blood cells, we are able to map speed patterns in embryos' vessels.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25273179','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25273179"><span>Asymmetric multiscale detrended <span class="hlt">cross-correlation</span> analysis of financial time series.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yin, Yi; Shang, Pengjian</p> <p>2014-09-01</p> <p>We propose the asymmetric multiscale detrended <span class="hlt">cross-correlation</span> analysis (MS-ADCCA) method and apply MS-ADCCA method to explore the existence of asymmetric <span class="hlt">cross-correlation</span> for daily price returns in US and Chinese stock markets and to assess the properties of these asymmetric <span class="hlt">cross-correlations</span>. The results all show the existences of asymmetric <span class="hlt">cross-correlations</span>, while small asymmetries at small scales and larger asymmetries at larger scales are also displayed. There is a strong similarity between S&P500 and DJI, and we reveal that the asymmetries depend more on the <span class="hlt">cross-correlations</span> of S&P500 vs. DJI, S&P500 vs. NQCI, DJI vs. NQCI, and ShangZheng vs. ShenCheng when the market is falling than rising, respectively. By comparing the spectra of S&P500 vs. NQCI and DJI vs. NQCI with uptrends and downtrends, we detect some new characteristics which lead to some new conclusions. Likewise, some new conclusions also can be drawn by the new characteristics displayed through the comparison between the spectra of ShangZheng vs. HSI and ShenCheng vs. HSI. Obviously, we conclude that although the overall spectra are similar and one market has the same effect when it is rising and falling in the study of asymmetric <span class="hlt">cross-correlations</span> between it and different markets, the <span class="hlt">cross-correlations</span> and asymmetries on the trends of the different markets are all different. MS-ADCCA method can detect the differences on the asymmetric <span class="hlt">cross-correlations</span> by different trends of markets. Moreover, the uniqueness of <span class="hlt">cross-correlation</span> between NQCI and HSI can be detected in the study of the asymmetric <span class="hlt">cross-correlations</span>, which confirms that HSI is unique in the Chinese stock markets and NQCI is unique in the US stock markets further.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014Chaos..24c2101Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014Chaos..24c2101Y"><span>Asymmetric multiscale detrended <span class="hlt">cross-correlation</span> analysis of financial time series</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yin, Yi; Shang, Pengjian</p> <p>2014-09-01</p> <p>We propose the asymmetric multiscale detrended <span class="hlt">cross-correlation</span> analysis (MS-ADCCA) method and apply MS-ADCCA method to explore the existence of asymmetric <span class="hlt">cross-correlation</span> for daily price returns in US and Chinese stock markets and to assess the properties of these asymmetric <span class="hlt">cross-correlations</span>. The results all show the existences of asymmetric <span class="hlt">cross-correlations</span>, while small asymmetries at small scales and larger asymmetries at larger scales are also displayed. There is a strong similarity between S&P500 and DJI, and we reveal that the asymmetries depend more on the <span class="hlt">cross-correlations</span> of S&P500 vs. DJI, S&P500 vs. NQCI, DJI vs. NQCI, and ShangZheng vs. ShenCheng when the market is falling than rising, respectively. By comparing the spectra of S&P500 vs. NQCI and DJI vs. NQCI with uptrends and downtrends, we detect some new characteristics which lead to some new conclusions. Likewise, some new conclusions also can be drawn by the new characteristics displayed through the comparison between the spectra of ShangZheng vs. HSI and ShenCheng vs. HSI. Obviously, we conclude that although the overall spectra are similar and one market has the same effect when it is rising and falling in the study of asymmetric <span class="hlt">cross-correlations</span> between it and different markets, the <span class="hlt">cross-correlations</span> and asymmetries on the trends of the different markets are all different. MS-ADCCA method can detect the differences on the asymmetric <span class="hlt">cross-correlations</span> by different trends of markets. Moreover, the uniqueness of <span class="hlt">cross-correlation</span> between NQCI and HSI can be detected in the study of the asymmetric <span class="hlt">cross-correlations</span>, which confirms that HSI is unique in the Chinese stock markets and NQCI is unique in the US stock markets further.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhyA..391.1179T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhyA..391.1179T"><span>Analysis of <span class="hlt">cross-correlations</span> in electroencephalogram signals as an approach to proactive diagnosis of schizophrenia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Timashev, Serge F.; Panischev, Oleg Yu.; Polyakov, Yuriy S.; Demin, Sergey A.; Kaplan, Alexander Ya.</p> <p>2012-02-01</p> <p>We apply flicker-noise spectroscopy (FNS), a time series analysis method operating on structure <span class="hlt">functions</span> and power spectrum estimates, to study the clinical electroencephalogram (EEG) signals recorded in children/adolescents (11 to 14 years of age) with diagnosed schizophrenia-spectrum symptoms at the National Center for Psychiatric Health (NCPH) of the Russian Academy of Medical Sciences. The EEG signals for these subjects were compared with the signals for a control sample of chronically depressed children/adolescents. The purpose of the study is to look for diagnostic signs of subjects' susceptibility to schizophrenia in the FNS parameters for specific electrodes and <span class="hlt">cross-correlations</span> between the signals simultaneously measured at different points on the scalp. Our analysis of EEG signals from scalp-mounted electrodes at locations F3 and F4, which are symmetrically positioned in the left and right frontal areas of cerebral cortex, respectively, demonstrates an essential role of frequency-phase synchronization, a phenomenon representing specific correlations between the characteristic frequencies and phases of excitations in the brain. We introduce quantitative measures of frequency-phase synchronization and systematize the values of FNS parameters for the EEG data. The comparison of our results with the medical diagnoses for 84 subjects performed at NCPH makes it possible to group the EEG signals into 4 categories corresponding to different risk levels of subjects' susceptibility to schizophrenia. We suggest that the introduced quantitative characteristics and classification of <span class="hlt">cross-correlations</span> may be used for the diagnosis of schizophrenia at the early stages of its development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20219681','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20219681"><span>Monitoring helicase-catalyzed DNA unwinding by fluorescence anisotropy and fluorescence <span class="hlt">cross-correlation</span> spectroscopy.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xi, Xu Guang; Deprez, Eric</p> <p>2010-07-01</p> <p>In order to elucidate molecular mechanism of helicases, we have developed two new rapid and sensitive fluorescence assays to measure helicase-mediated DNA unwinding. The fluorescence anisotropy (FA) assay takes the advantage of the substantial change in fluorescence polarization upon helicase binding to DNA and DNA unwinding. The extent of depolarization depends on the rate of tumbling of the fluorescently labeled DNA molecule, which decreases with increasing size. This assay therefore can simultaneously monitor the DNA binding of helicase and the subsequent helicase-catalyzed DNA unwinding in real-time. For size limitation reasons, the FA approach is more suitable for single-turnover kinetic studies. A fluorescence <span class="hlt">cross-correlation</span> spectroscopy method (FCCS) is also described for measuring DNA unwinding. This assay is based on the degree of concomitant diffusion of the two complementary DNA strands in a small excitation volume, each labeled by a different color. The decrease in the amplitude of the <span class="hlt">cross-correlation</span> signal is then directly related to the unwinding activity. By contrast with FA, the FCCS-based assay can be used to measure the unwinding activity under both single- and multiple-turnover conditions, with no limitation related to the size of the DNA strands constituting the DNA substrate. These methods used together have proven to be useful for studying molecular mechanism underlying efficient motor <span class="hlt">function</span> of helicases. Here, we describe the theoretical basis and framework of FA and FCCS and some practical implications for measuring DNA binding and unwinding. We discuss sample preparation and potential troubleshooting. Special attention is paid to instrumentation, data acquisition and analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11561923','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11561923"><span>Mental rotation of objects <span class="hlt">retrieved</span> from memory: a <span class="hlt">functional</span> MRI study of spatial processing.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Just, M A; Carpenter, P A; Maguire, M; Diwadkar, V; McMains, S</p> <p>2001-09-01</p> <p>This <span class="hlt">functional</span> MRI study examined how people mentally rotate a 3-dimensional object (an alarm clock) that is <span class="hlt">retrieved</span> from memory and rotated according to a sequence of auditory instructions. We manipulated the geometric properties of the rotation, such as having successive rotation steps around a single axis versus alternating between 2 axes. The latter condition produced much more activation in several areas. Also, the activation in several areas increased with the number of rotation steps. During successive rotations around a single axis, the activation was similar for rotations in the picture plane and rotations in depth. The parietal (but not extrastriate) activation was similar to mental rotation of a visually presented object. The findings indicate that a large-scale cortical network computes different types of spatial information by dynamically drawing on each of its components to a differential, situation-specific degree.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SPIE.7623E..14V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SPIE.7623E..14V"><span>Learning discriminative distance <span class="hlt">functions</span> for valve <span class="hlt">retrieval</span> and improved decision support in valvular heart disease</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Voigt, Ingmar; Vitanovski, Dime; Ionasec, Razvan I.; Tsymal, Alexey; Georgescu, Bogdan; Zhou, Shaohua K.; Huber, Martin; Navab, Nassir; Hornegger, Joachim; Comaniciu, Dorin</p> <p>2010-03-01</p> <p>Disorders of the heart valves constitute a considerable health problem and often require surgical intervention. Recently various approaches were published seeking to overcome the shortcomings of current clinical practice,that still relies on manually performed measurements for performance assessment. Clinical decisions are still based on generic information from clinical guidelines and publications and personal experience of clinicians. We present a framework for <span class="hlt">retrieval</span> and decision support using learning based discriminative distance <span class="hlt">functions</span> and visualization of patient similarity with relative neighborhood graphsbased on shape and derived features. We considered two learning based techniques, namely learning from equivalence constraints and the intrinsic Random Forest distance. The generic approach enables for learning arbitrary user-defined concepts of similarity depending on the application. This is demonstrated with the proposed applications, including automated diagnosis and interventional suitability classification, where classification rates of up to 88.9% and 85.9% could be observed on a set of valve models from 288 and 102 patients respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2876832','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2876832"><span><span class="hlt">Functional</span> interface micromechanics of 11 en-bloc <span class="hlt">retrieved</span> cemented femoral hip replacements</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Miller, Mark A; Verdonschot, Nico; Izant, Timothy H; Race, Amos</p> <p>2010-01-01</p> <p>Background and purpose Despite the longstanding use of micromotion as a measure of implant stability, direct measurement of the micromechanics of implant/bone interfaces from en bloc human <span class="hlt">retrievals</span> has not been performed. The purpose of this study was to determine the stem-cement and cement-bone micromechanics of <span class="hlt">functionally</span> loaded, en-bloc <span class="hlt">retrieved</span>, cemented femoral hip components. Methods 11 fresh frozen proximal femurs with cemented implants were <span class="hlt">retrieved</span> at autopsy. Specimens were sectioned transversely into 10-mm slabs and fixed to a loading device where <span class="hlt">functional</span> torsional loads were applied to the stem. A digital image correlation technique was used to document micromotions at stem-cement and cement-bone interfaces during loading. Results There was a wide range of responses with stem-cement micromotions ranging from 0.0006 mm to 0.83 mm (mean 0.17 mm, SD 0.29) and cement-bone micromotions ranging from 0.0022 mm to 0.73 mm (mean 0.092 mm, SD 0.22). There was a strong (linear-log) inverse correlation between apposition fraction and micromotion at the stem-cement interface (r2 = 0.71, p < 0.001). There was a strong inverse log-log correlation between apposition fraction at the cement-bone interface and micromotion (r2 = 0.85, p < 0.001). Components that were radiographically well-fixed had a relatively narrow range of micromotions at the stem-cement (0.0006–0.057 mm) and cement-bone (0.0022–0.029 mm) interfaces. Interpretatation Minimizing gaps at the stem-cement interface and encouraging bony apposition at the cement-bone interface would be clinically desirable. The cement-bone interface does not act as a bonded interface in actual use, even in radiographically well-fixed components. Rather, the interface is quite compliant, with sliding and opening motions between the cement and bone surfaces. PMID:20367421</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4823478','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4823478"><span>The Hip <span class="hlt">Functional</span> <span class="hlt">Retrieval</span> after Elective Surgery May Be Enhanced by Supplemented Essential Amino Acids</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Baldissarro, Eleonora; Aquilani, Roberto; Boschi, Federica; Baiardi, Paola; Iadarola, Paolo; Fumagalli, Marco; Pasini, Evasio; Verri, Manuela; Dossena, Maurizia; Gambino, Arianna; Cammisuli, Sharon; Viglio, Simona</p> <p>2016-01-01</p> <p>It is not known whether postsurgery systemic inflammation and plasma amino acid abnormalities are still present during rehabilitation of individuals after elective hip arthroplasty (EHA). Sixty subjects (36 females; age 66.58 ± 8.37 years) were randomized to receive 14-day oral EAAs (8 g/day) or a placebo (maltodextrin). At admission to and discharge from the rehabilitation center, serum C-reactive protein (CRP) and venous plasma amino acid concentrations were determined. Post-EHA hip <span class="hlt">function</span> was evaluated by Harris hip score (HHS) test. Ten matched healthy subjects served as controls. At baseline, all patients had high CRP levels, considerable reduction in several amino acids, and severely reduced hip <span class="hlt">function</span> (HHS 40.78 ± 2.70 scores). After treatment, inflammation decreased both in the EAA group and in the placebo group. Only EAA patients significantly improved their levels of glycine, alanine, tyrosine, and total amino acids. In addition, they enhanced the rate of hip <span class="hlt">function</span> recovery (HHS) (from baseline 41.8 ± 1.15 to 76.37 ± 6.6 versus baseline 39.78 ± 4.89 to 70.0 ± 7.1 in placebo one; p = 0.006). The study documents the persistence of inflammation and plasma amino acid abnormalities in post-EHA rehabilitation phase. EAAs enhance hip <span class="hlt">function</span> <span class="hlt">retrieval</span> and improve plasma amino acid abnormalities. PMID:27110573</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EntIS...6..433Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EntIS...6..433Z"><span>Term frequency - <span class="hlt">function</span> of document frequency: a new term weighting scheme for enterprise information <span class="hlt">retrieval</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Hui; Wang, Deqing; Wu, Wenjun; Hu, Hongping</p> <p>2012-11-01</p> <p>In today's business environment, enterprises are increasingly under pressure to process the vast amount of data produced everyday within enterprises. One method is to focus on the business intelligence (BI) applications and increasing the commercial added-value through such business analytics activities. Term weighting scheme, which has been used to convert the documents as vectors in the term space, is a vital task in enterprise Information <span class="hlt">Retrieval</span> (IR), text categorisation, text analytics, etc. When determining term weight in a document, the traditional TF-IDF scheme sets weight value for the term considering only its occurrence frequency within the document and in the entire set of documents, which leads to some meaningful terms that cannot get the appropriate weight. In this article, we propose a new term weighting scheme called Term Frequency - <span class="hlt">Function</span> of Document Frequency (TF-FDF) to address this issue. Instead of using monotonically decreasing <span class="hlt">function</span> such as Inverse Document Frequency, FDF presents a convex <span class="hlt">function</span> that dynamically adjusts weights according to the significance of the words in a document set. This <span class="hlt">function</span> can be manually tuned based on the distribution of the most meaningful words which semantically represent the document set. Our experiments show that the TF-FDF can achieve higher value of Normalised Discounted Cumulative Gain in IR than that of TF-IDF and its variants, and improving the accuracy of relevance ranking of the IR results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JSV...332...43B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JSV...332...43B"><span>Fiber Bragg grating sensor fatigue crack real-time monitoring based on spectrum <span class="hlt">cross-correlation</span> analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bao, Pengyu; Yuan, Mei; Dong, Shaopeng; Song, Hao; Xue, Jingfeng</p> <p>2013-01-01</p> <p>As one of the most critical tasks in structural damage monitoring, real-time fatigue crack monitoring plays an important role in improving the durability of a structure. In this paper, an online fatigue crack detection method is investigated based on the fiber Bragg grating (FBG) crack monitoring test bed (FBG-CMTB). Aiming at detecting ultrasonic spread in the structure when the crack is growing, the spectrum <span class="hlt">cross-correlation</span> analysis algorithm and the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> sequence are two methods that we will investigate in detail. Considering the singularity characteristic of the crack detecting signals when crack initiates, the wavelet packet analysis method is applied for feature extraction and two damage factors, crack initiation factor (CIF) and crack propagation factor (CPF), are constructed for damage initiation and propagation degree identification. To analyze the efficiency of this method, this paper presents the comparison tests based on different sensors array, FBG and acoustic emission (AE). Experimental results shows a satisfactory performance of the proposed spectrum <span class="hlt">cross-correlation</span> analysis (SCCA) and damage feature factors on the fatigue crack online monitoring.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26172763','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26172763"><span>Detrended partial <span class="hlt">cross-correlation</span> analysis of two nonstationary time series influenced by common external forces.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Qian, Xi-Yuan; Liu, Ya-Min; Jiang, Zhi-Qiang; Podobnik, Boris; Zhou, Wei-Xing; Stanley, H Eugene</p> <p>2015-06-01</p> <p>When common factors strongly influence two power-law <span class="hlt">cross-correlated</span> time series recorded in complex natural or social systems, using detrended <span class="hlt">cross-correlation</span> analysis (DCCA) without considering these common factors will bias the results. We use detrended partial <span class="hlt">cross-correlation</span> analysis (DPXA) to uncover the intrinsic power-law <span class="hlt">cross</span> <span class="hlt">correlations</span> between two simultaneously recorded time series in the presence of nonstationarity after removing the effects of other time series acting as common forces. The DPXA method is a generalization of the detrended <span class="hlt">cross-correlation</span> analysis that takes into account partial correlation analysis. We demonstrate the method by using bivariate fractional Brownian motions contaminated with a fractional Brownian motion. We find that the DPXA is able to recover the analytical cross Hurst indices, and thus the multiscale DPXA coefficients are a viable alternative to the conventional <span class="hlt">cross-correlation</span> coefficient. We demonstrate the advantage of the DPXA coefficients over the DCCA coefficients by analyzing contaminated bivariate fractional Brownian motions. We calculate the DPXA coefficients and use them to extract the intrinsic <span class="hlt">cross</span> <span class="hlt">correlation</span> between crude oil and gold futures by taking into consideration the impact of the U.S. dollar index. We develop the multifractal DPXA (MF-DPXA) method in order to generalize the DPXA method and investigate multifractal time series. We analyze multifractal binomial measures masked with strong white noises and find that the MF-DPXA method quantifies the hidden multifractal nature while the multifractal DCCA method fails.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvE..91f2816Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvE..91f2816Q"><span>Detrended partial <span class="hlt">cross-correlation</span> analysis of two nonstationary time series influenced by common external forces</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Qian, Xi-Yuan; Liu, Ya-Min; Jiang, Zhi-Qiang; Podobnik, Boris; Zhou, Wei-Xing; Stanley, H. Eugene</p> <p>2015-06-01</p> <p>When common factors strongly influence two power-law <span class="hlt">cross-correlated</span> time series recorded in complex natural or social systems, using detrended <span class="hlt">cross-correlation</span> analysis (DCCA) without considering these common factors will bias the results. We use detrended partial <span class="hlt">cross-correlation</span> analysis (DPXA) to uncover the intrinsic power-law <span class="hlt">cross</span> <span class="hlt">correlations</span> between two simultaneously recorded time series in the presence of nonstationarity after removing the effects of other time series acting as common forces. The DPXA method is a generalization of the detrended <span class="hlt">cross-correlation</span> analysis that takes into account partial correlation analysis. We demonstrate the method by using bivariate fractional Brownian motions contaminated with a fractional Brownian motion. We find that the DPXA is able to recover the analytical cross Hurst indices, and thus the multiscale DPXA coefficients are a viable alternative to the conventional <span class="hlt">cross-correlation</span> coefficient. We demonstrate the advantage of the DPXA coefficients over the DCCA coefficients by analyzing contaminated bivariate fractional Brownian motions. We calculate the DPXA coefficients and use them to extract the intrinsic <span class="hlt">cross</span> <span class="hlt">correlation</span> between crude oil and gold futures by taking into consideration the impact of the U.S. dollar index. We develop the multifractal DPXA (MF-DPXA) method in order to generalize the DPXA method and investigate multifractal time series. We analyze multifractal binomial measures masked with strong white noises and find that the MF-DPXA method quantifies the hidden multifractal nature while the multifractal DCCA method fails.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006SPIE.6047E..2LL','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006SPIE.6047E..2LL"><span>Ultrasensitive detection of genetically modified plants by fluorescence <span class="hlt">cross-correlation</span> spectroscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Junfeng; Xing, Da; Chen, Tongsheng; Liu, Jinfeng</p> <p>2006-09-01</p> <p>In this study, a novel method for the direct detection of GMP without amplified by the general method of PCR is firstly presented and proved by experiments. In our method, fluorescence correlation spectroscopy, cleaving nucleic acid by restriction endonuclease and two nucleic acid probe hybridization techniques are combined to distinguish the caulifiower mosaic virus (CaMV) 35S promoter and determine whether samples contain genetically modified components. The detection principle is as follows: firstly two restriction endonucleases FOKI and BsrDlare used to cleave the genomic DNA and the 169bp fragments of CaMV 35S promoter are <span class="hlt">retrieved</span>; secondly, two nucleic acid probes labeled by Rhodamine Green and y5 dyes respectively hybridize with cleaved 169bp fragments of CaMV 35S promoter; thirdly, the hybridization products simultaneously with two dye-labeled probes are detected by fluorescence <span class="hlt">cross-correlation</span> spectroscopy and GMP is distinguished. As the detection and analysis by FCS can be performed at the level of single molecule, there is no need for any type of amplification. Genetically modified tobaccos are measured by this method. The results indicate this method can detect CaMV 35S promoter of GMP exactly and the sensitivity can be down to 3.47X10 -10M. Because no any type of amplification is involved, this method can avoid the non-specffic amplification and false-positive problems of PCR, Due to its high-sensitivity, simplicity, reliability and little need for sample amounts, this method promises to be a highly effective detection method for GMP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S51E..08Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S51E..08Y"><span>Characteristics of Scholte-Rayleigh waves and reflected body waves recovered by ocean bottom ambient noise <span class="hlt">cross-correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yao, H.; Gao, C.; Lin, C.</p> <p>2013-12-01</p> <p>Ambient noise interferometry has been widely used to recover surface waves for understanding the crustal and lithospheric structures. Recent studies have shown that body wave reflections from deep mantle and core discontinuities can be successfully <span class="hlt">retrieved</span> by stacking ambient noise <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> (CFs) of many different land-station pairs. Here we report that not only surface waves but also reflected body waves from mantle transition zone discontinuities can be successfully recovered from one-year ambient noise data recorded by ocean bottom seismometers near equatorial eastern Pacific Rise. The recovered surface waves include Scholte-Rayleigh waves on the vertical-vertical (Z-Z) and radial-radial (R-R) component CFs and Love waves on the transverse-transverse (T-T) component CFs. On the Z-Z component CFs, we observe both the fundamental mode and the first higher mode Scholte-Rayleigh waves in the period band 2 - 10 s; however, on the R-R component CFs, we only observe the first higher mode, which has the same dispersion characteristics of that on the Z-Z component CFs. Synthetic radial component seismograms as the result of a radial-direction point source in the shallow sediment layer explain the missing of fundamental mode Scholte-Rayleigh waves on the R-R component CFs, which are primarily sensitive to very low rigidity and high attenuation shallow sedimentary layers below the ocean bottom. We also observe clear body wave reflections in the period band 5 - 10 s from mantle transition zone discontinuities, e.g., 410 km and 660 km discontinuities, on many single station-pair CFs without stacking over many different station pairs. In particular, these deep reflected signals appear quite stable on almost every daily CF and the amplitude and phase of these reflections show great symmetry on the yearly-stacked CFs. The ambient noise sources to generate these deep reflected signals are probably from ocean wave pressure exerted on the seafloor, as the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.S13A1967Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.S13A1967Y"><span>Crustal Structure of the Chukuo Fault Zone Extracted from the <span class="hlt">Cross-Correlation</span> of Ambient Seismic Noise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yeh, Y.; Wen, S.; Chen, C.</p> <p>2010-12-01</p> <p>ABSTRACT The highly-populated Chia-Nan area in the southwestern Taiwan is located at the active deformation front of the collision of the Eurasian continental plate and the Philippine Sea plate, which causes complex folds as well as thrust fault systems in the area. The well-known Chukuo Fault is an active thrust fault and plays as a boundary between the Western Foothill and the Coastal Plain. The strike of the fault is in the N-S direction. The dip angle of the fault plane near the surface is 60 degrees toward to the east, while the dip angle is about 30-40 degrees at the lower part of the fault plane. However, the nature of the crustal structure beneath the fault zone is less understood. With the high quality broadband seismic network deployed along the ChuKuo Fault in recent year, we are able to have better insight in the characteristics of crustal structure of the Chukuo Fault zone. In this study, we have <span class="hlt">retrieved</span> Rayleigh wave Green’s <span class="hlt">functions</span> for all stations pairs separated by 5-30 km by <span class="hlt">cross-correlation</span> of ambient noise, which was recorded from 2004 to 2006. The multiple filter technique is applied to perform dispersion analysis. We further obtain an adapted crustal shear-wave velocity structure of the Chukuo Fault zone at period between 1 to 5 seconds using the Neighborhood Algorithm (NA) which minimizes the misfit between the observed and synthetic dispersion curve. We find that the shear-wave velocity at the western side (footwall) of the fault is much greater (up to 20% of difference) than that at the eastern side (hanging wall) of the fault at shallow crustal area (~ 10 km in depth). From the study of microearthquake seismicity at the fault zone, which shows that most earthquakes occurred at the eastern side of the fault and tends to be clustered at the depth between 10 to 12 km. Thus, both results imply that the eastern side of the fault is highly fractured due to intensive deformation caused by plate collision.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25642739','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25642739"><span>Surface Topographical Changes of a Failing Acid-Etched Long-Term in <span class="hlt">Function</span> <span class="hlt">Retrieved</span> Dental Implant.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Monje, Alberto; González-García, Raúl; Fernández-Calderón, María Coronada; Hierro-Oliva, Margarita; González-Martín, María Luisa; Del Amo, Fernando Suarez-Lopez; Galindo-Moreno, Pablo; Wang, Hom-Lay; Monje, Florencio</p> <p>2016-02-01</p> <p>The aim of the present study was to report the main topographical and chemical changes of a failing 18-year in <span class="hlt">function</span> <span class="hlt">retrieved</span> acid-etching implant in the micro- and nanoscales. A partially edentulous 45 year old rehabilitated with a dental implant at 18 years of age exhibited mobility. After careful examination, a 3.25 × 13-mm press-fit dental implant was <span class="hlt">retrieved</span>. Scanning electron microscope (SEM) analysis was carried out to study topographical changes of the <span class="hlt">retrieved</span> implant compared with an unused implant with similar topographical characteristics. Moreover, X-ray photoelectron spectroscopy (XPS) analysis was used to study the surface composition of the <span class="hlt">retrieved</span> failing implant. Clear changes related to the dual dioxide layer are present as visible in ≥×500 magnification. In addition, it was found that, for the <span class="hlt">retrieved</span> implant, the surface composition consisted mainly of Ti2p, O1s, C1s, and Al2p. Also, a meaningful decrease of N and C was noticed, whereas the peaks of Ti2p, Al2p, and O1s increased when analyzing deeper (up to ×2000s) in the sample. It was shown that the superficial surface of a <span class="hlt">retrieved</span> press-fit dual acid-etched implant 18 years after placement is impaired. However, the causes and consequences for these changes cannot be determined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhyA..434...52G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhyA..434...52G"><span>Multifractal Detrended <span class="hlt">Cross-correlation</span> Analysis of Market Clearing Price of electricity and SENSEX in India</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ghosh, Dipak; Dutta, Srimonti; Chakraborty, Sayantan</p> <p>2015-09-01</p> <p>This paper reports a study on the <span class="hlt">cross-correlation</span> between the electric bid price and SENSEX using Multifractal Detrended <span class="hlt">Cross-correlation</span> Analysis (MF-DXA). MF-DXA is a very rigorous and robust technique for assessment of cross-correction between two non-linear time series. The study reveals power law <span class="hlt">cross-correlation</span> between Market Clearing Price (MCP) and SENSEX which suggests that a change in the value of one can create a subjective change in the value of the other.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17410229','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17410229"><span>Long-term femtosecond timing link stabilization using a single-crystal balanced <span class="hlt">cross</span> <span class="hlt">correlator</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kim, J; Chen, J; Zhang, Z; Wong, F N C; Kärtner, F X; Loehl, F; Schlarb, H</p> <p>2007-05-01</p> <p>We demonstrate a self-aligned balanced <span class="hlt">cross</span> <span class="hlt">correlator</span> based on a single type-II phase-matched periodically poled KTiOPO4 crystal. The birefringence of the crystal generates a walk-off between the two orthogonally polarized pulses. This enables the balancing of the <span class="hlt">cross</span> <span class="hlt">correlator</span> with input pulses at the same center wavelength. As a first application of this single-crystal balanced <span class="hlt">cross</span> <span class="hlt">correlator</span>, we stabilized a 310 m long optical fiber link for timing distribution with long-term stable 10 fs precision.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MNRAS.453..819K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MNRAS.453..819K"><span><span class="hlt">Retrieval</span> of Garstang's emission <span class="hlt">function</span> from all-sky camera images</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kocifaj, Miroslav; Solano Lamphar, Héctor Antonio; Kundracik, František</p> <p>2015-10-01</p> <p>The emission <span class="hlt">function</span> from ground-based light sources predetermines the skyglow features to a large extent, while most mathematical models that are used to predict the night sky brightness require the information on this <span class="hlt">function</span>. The radiant intensity distribution on a clear sky is experimentally determined as a <span class="hlt">function</span> of zenith angle using the theoretical approach published only recently in MNRAS, 439, 3405-3413. We have made the experiments in two localities in Slovakia and Mexico by means of two digital single lens reflex professional cameras operating with different lenses that limit the system's field-of-view to either 180º or 167º. The purpose of using two cameras was to identify variances between two different apertures. Images are taken at different distances from an artificial light source (a city) with intention to determine the ratio of zenith radiance relative to horizontal irradiance. Subsequently, the information on the fraction of the light radiated directly into the upward hemisphere (F) is extracted. The results show that inexpensive devices can properly identify the upward emissions with adequate reliability as long as the clear sky radiance distribution is dominated by a largest ground-based light source. Highly unstable turbidity conditions can also make the parameter F difficult to find or even impossible to <span class="hlt">retrieve</span>. The measurements at low elevation angles should be avoided due to a potentially parasitic effect of direct light emissions from luminaires surrounding the measuring site.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC42B..08H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC42B..08H"><span>Temporal Variability of Surface Solar Irradiance as a <span class="hlt">Function</span> of Satellite-<span class="hlt">retrieved</span> Cloud</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hinkelman, L. M.; Sengupta, M.; Habte, A.</p> <p>2014-12-01</p> <p>Studies of the impact of renewables on the electrical transmission grid are needed as power production from renewable energy resources increases. These studies require estimates of high temporal and spatial resolution power output under various scenarios. Satellite-based solar resource estimates are the best source of long-term irradiance data but are generally of lower temporal and spatial resolution than needed and thus require downscaling. Likewise, weather forecast models cannot provide high spatial or temporal irradiance predictions. Downscaling requires information about solar irradiance variability in both space and time, which is primarily a <span class="hlt">function</span> of cloud properties. In this study, we analyze the relationships between the temporal variability of surface solar irradiance and satellite-based cloud properties. One-minute resolution surface solar irradiance data were obtained from the National Oceanic and Atmospheric Administration's Surface Radiation (SURFRAD) network. These sites are distributed across the United States to cover a range of meteorological conditions. Cloud information at a nominal 4 km resolution and half hour intervals was <span class="hlt">retrieved</span> from NOAA's Geostationary Operation Environmental Satellites (GOES). The <span class="hlt">retrieved</span> cloud properties were then used to select and composite irradiance data from the measurement sites in order to identify the cloud properties that exert the strongest control over short-term irradiance variability. The irradiance variability was characterized using statistics of both the irradiances themselves and of irradiance differences computed for short time scales (minutes). The relationships derived using this method will be presented, comparing and contrasting the statistics computed for the different cloud properties. The implications for downscaling irradiance from satellites or forecast models will also be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21216747','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21216747"><span>Rice TOGO Browser: A platform to <span class="hlt">retrieve</span> integrated information on rice <span class="hlt">functional</span> and applied genomics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nagamura, Yoshiaki; Antonio, Baltazar A; Sato, Yutaka; Miyao, Akio; Namiki, Nobukazu; Yonemaru, Jun-ichi; Minami, Hiroshi; Kamatsuki, Kaori; Shimura, Kan; Shimizu, Yuji; Hirochika, Hirohiko</p> <p>2011-02-01</p> <p>The Rice TOGO Browser is an online public resource designed to facilitate integration and visualization of mapping data of bacterial artificial chromosome (BAC)/P1-derived artificial chromosome (PAC) clones, genes, restriction fragment length polymorphism (RFLP)/simple sequence repeat (SSR) markers and phenotype data represented as quantitative trait loci (QTLs) onto the genome sequence, and to provide a platform for more efficient utilization of genome information from the point of view of applied genomics as well as <span class="hlt">functional</span> genomics. Three search options, namely keyword search, region search and trait search, generate various types of data in a user-friendly interface with three distinct viewers, a chromosome viewer, an integrated map viewer and a sequence viewer, thereby providing the opportunity to view the position of genes and/or QTLs at the chromosomal level and to <span class="hlt">retrieve</span> any sequence information in a user-defined genome region. Furthermore, the gene list, marker list and genome sequence in a specified region delineated by RFLP/SSR markers and any sequences designed as primers can be viewed and downloaded to support forward genetics approaches. An additional feature of this database is the graphical viewer for BLAST search to reveal information not only for regions with significant sequence similarity but also for regions adjacent to those with similarity but with no hits between sequences. An easy to use and intuitive user interface can help a wide range of users in <span class="hlt">retrieving</span> integrated mapping information including agronomically important traits on the rice genome sequence. The database can be accessed at http://agri-trait.dna.affrc.go.jp/.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014IAUS..306..397L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014IAUS..306..397L"><span>X-ray <span class="hlt">cross-correlation</span> analysis of the low-mass X-ray binary 4U 1636-53</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lei, Ya-Juan</p> <p>2014-05-01</p> <p>We analyze the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> of the soft and hard X-rays of the atoll source 4U 1636-53 with RXTE data. The results show that the <span class="hlt">cross-correlations</span> evolve along the different branches of the color-color diagram. At the lower left banana states, we have both positive and ambiguous correlations, and positive correlations are dominant for the lower banana and the upper banana states. The anti-correlation is detected at the top of the upper banana states. The <span class="hlt">cross-correlations</span> of two atoll sources 4U 1735-44 and 4U 1608-52 have been studied in previous work, and the anti-correlations are detected at the lower left banana or the top of the upper banana states. Our results show that, in the 4U 1636-53, the distribution of the <span class="hlt">cross-correlations</span> in the color-color diagram is similar to those of 4U 1735-44 and 4U 1608-52, and confirm further that the distribution of <span class="hlt">cross-correlations</span> in color-color diagram could be correlated with the luminosity of the source.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ESASP.740E..89S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ESASP.740E..89S"><span>SynSen PFT: Synergistic <span class="hlt">Retrieval</span> of Phytoplankton <span class="hlt">Functional</span> Types from Space From Hyper-and Multispectral Measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Soppa, Mariana A.; Loza, Svetlana N.; Dinter, Tilman; Wolanin, Aleksandra; Bricaud, Annick; Brewein, Robert; Rozanov, Vladimir; Barcher, Astrid</p> <p>2016-08-01</p> <p>To gain knowledge on the role of marine phytoplankton in the global marine ecosystem and biogeochemical cycles, information on the global distribution of major phytoplankton <span class="hlt">functional</span> types is essential. The Synergistic <span class="hlt">Retrieval</span> of Phytoplankton <span class="hlt">Functional</span> Types from Space from Hyper- and Multispectral Measurements project (SynSenPFT) aims to improve the <span class="hlt">retrieval</span> of phytoplankton types (PFTs) from space by exploring the synergistic use of low-spatial-hyper- spectral and high-spatial-multi-spectral satellite data. Three PFTs are investigated: diatoms, coccolithophores and cyanobacteria. The work involves the improvement/revision of existing PFT algorithms based on hyper- (PhytoDOAS, [1]) and multi-spectral (OC- PFT, [2]) datasets, development of synergistic PFT products combining the <span class="hlt">retrievals</span> of these two algorithms and intercomparison of the synergistic PFT products with those derived from other methods [3,4,5].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999SPIE.3870..243N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999SPIE.3870..243N"><span>Laboratory characterization of a CCD camera system for <span class="hlt">retrieval</span> of bi-directional reflectance distribution <span class="hlt">function</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nandy, Prabal; Thome, Kurtis J.; Biggar, Stuart F.</p> <p>1999-12-01</p> <p>The Remote Sensing Group of the Optical Science Center at the University of Arizona has developed a four-band, multi- spectral, wide-angle, imaging radiometer for the <span class="hlt">retrieval</span> of the bi-directional reflectance distribution <span class="hlt">function</span> (BRDF) for vicarious calibration applications. The system consists of a fisheye lens with four interference filters centered at 470 nm, 575 nm, 660 nm, and 835 nm for spectral selection and an astronomical grade 1024 X 1024-pixel, silicon CCD array. Data taken by the system fit in the array as a nominally 0.2 degree per pixel image. This imaging radiometer system has been used in support of the calibration of Landsat-5 and SPOT- satellite sensors. This paper presents the results of laboratory characterization of the system to determine linearity of the detector, point spread <span class="hlt">function</span> (PSF) and polarization effects. The linearity study was done on detector array without the lens, using a spherical-integrating source with a 1.5-mm aperture. This aperture simulates a point source for distances larger than 60 cm. Data were collected as both a <span class="hlt">function</span> of exposure time and distance from the source. The results of these measurements indicate that each detector of the array is linear to better than 0.5%. Assuming a quadratic response improves this fit to better than 0.1% over 88% of the upper end of the detector's dynamic range. The point spread <span class="hlt">function</span> (PSF) of the lens system was measured using the sphere source and aperture with the full camera system operated at a distance of 700 mm from the source, thus the aperture subtends less than the field of view of one pixel. The PSF was measured for several field angles and the signal level was found to fall to less than 1% of the peak signal within 1.5-degrees (10 pixels) for the on-axis case. The effect of this PSF on the <span class="hlt">retrieval</span> of modeled BRDFs is shown to be less than 0.2% out to view angles of 70 degrees. The final test presented is one to assess the polarization effects of the lens</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1366777','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1366777"><span>Determining Protease Activity In Vivo by Fluorescence <span class="hlt">Cross-Correlation</span> Analysis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kohl, Tobias; Haustein, Elke; Schwille, Petra</p> <p>2005-01-01</p> <p>To date, most biochemical approaches to unravel protein <span class="hlt">function</span> have focused on purified proteins in vitro. Whereas they analyze enzyme performance under assay conditions, they do not necessarily tell us what is relevant within a living cell. Ideally, cellular <span class="hlt">functions</span> should be examined in situ. In particular, association/dissociation reactions are ubiquitous, but so far there is no standard technique permitting online analysis of these processes in vivo. Featuring single-molecule sensitivity combined with intrinsic averaging, fluorescence correlation spectroscopy is a minimally invasive technique ideally suited to monitor proteins. Moreover, endogenous fluorescence-based assays can be established by genetically encoding fusions of autofluorescent proteins and cellular proteins, thus avoiding the disadvantages of in vitro protein labeling and subsequent delivery to cells. Here, we present an in vivo protease assay as a model system: Green and red autofluorescent proteins were connected by Caspase-3- sensitive and insensitive protein linkers to create double-labeled protease substrates. Then, dual-color fluorescence <span class="hlt">cross-correlation</span> spectroscopy was employed to study the protease reaction in situ. Allowing assessment of multiple dynamic parameters simultaneously, this method provided internal calibration and improved experimental resolution for quantifying protein stability. This approach, which is easily extended to reversible protein-protein interactions, seems very promising for elucidating intracellular protein <span class="hlt">functions</span>. PMID:16055538</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..473..620H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..473..620H"><span>Power law <span class="hlt">cross-correlations</span> between price change and volume change of Indian stocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hasan, Rashid; Mohammed Salim, M.</p> <p>2017-05-01</p> <p>We study multifractal long-range correlations and <span class="hlt">cross-correlations</span> of daily price change and volume change of 50 stocks that comprise Nifty index of National Stock Exchange, Mumbai, using MF-DFA and MF-DCCA methods. We find that the time series of price change are uncorrelated, whereas anti-persistent long-range multifractal correlations are found in volume change series. We also find antipersistent long-range multifractal <span class="hlt">cross-correlations</span> between the time series of price change and volume change. As multifractality is a signature of complexity, we estimate complexity parameters of the time series of price change, volume change, and <span class="hlt">cross-correlated</span> price-volume change by fitting the fourth-degree polynomials to their multifractal spectra. Our results indicate that the time series of price change display high complexity, whereas the time series of volume change and <span class="hlt">cross-correlated</span> price-volume change display low complexity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhyA..419..513K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhyA..419..513K"><span>Finite sample properties of power-law <span class="hlt">cross-correlations</span> estimators</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kristoufek, Ladislav</p> <p>2015-02-01</p> <p>We study finite sample properties of estimators of power-law <span class="hlt">cross-correlations</span>-detrended <span class="hlt">cross-correlation</span> analysis (DCCA), height <span class="hlt">cross-correlation</span> analysis (HXA) and detrending moving-average <span class="hlt">cross-correlation</span> analysis (DMCA)-with a special focus on short-term memory bias as well as power-law coherency. We present a broad Monte Carlo simulation study that focuses on different time series lengths, specific methods' parameter setting, and memory strength. We find that each method is best suited for different time series dynamics so that there is no clear winner between the three. The method selection should be then made based on observed dynamic properties of the analyzed series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015FNL....1450023Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015FNL....1450023Y"><span>Multiscale Detrended <span class="hlt">Cross-Correlation</span> Analysis of Traffic Time Series Based on Empirical Mode Decomposition</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yin, Yi; Shang, Pengjian</p> <p>2015-04-01</p> <p>In this paper, we propose multiscale detrended <span class="hlt">cross-correlation</span> analysis (MSDCCA) to detect the long-range power-law <span class="hlt">cross-correlation</span> of considered signals in the presence of nonstationarity. For improving the performance and getting better robustness, we further introduce the empirical mode decomposition (EMD) to eliminate the noise effects and propose MSDCCA method combined with EMD, which is called MS-EDXA method, then systematically investigate the multiscale <span class="hlt">cross-correlation</span> structure of the real traffic signals. We apply the MSDCCA and MS-EDXA methods to study the <span class="hlt">cross-correlations</span> in three situations: velocity and volume on one lane, velocities on the present and the next moment and velocities on the adjacent lanes, and further compare their spectrums respectively. When the difference between the spectrums of MSDCCA and MS-EDXA becomes unobvious, there is a crossover which denotes the turning point of difference. The crossover results from the competition between the noise effects in the original signals and the intrinsic fluctuation of traffic signals and divides the plot of spectrums into two regions. In all the three case, MS-EDXA method makes the average of local scaling exponents increased and the standard deviation decreased and provides a relative stable persistent scaling <span class="hlt">cross-correlated</span> behavior which gets the analysis more precise and more robust and improves the performance after noises being removed. Applying MS-EDXA method avoids the inaccurate characteristics of multiscale <span class="hlt">cross-correlation</span> structure at the short scale including the spectrum minimum, the range for the spectrum fluctuation and general trend, which are caused by the noise in the original signals. We get the conclusions that the traffic velocity and volume are long-range <span class="hlt">cross-correlated</span>, which is accordant to their actual evolution, while velocities on the present and the next moment and velocities on adjacent lanes reflect the strong <span class="hlt">cross-correlations</span> both in temporal and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1357203','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1357203"><span>A <span class="hlt">cross-correlation</span> study of the <i>Fermi</i>-LAT γ-ray diffuse extragalactic signal</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xia, Jun -Qing; Cuoco, Alessandro; Branchini, Enzo; Fornasa, Mattia; Viel, Matteo</p> <p>2011-09-12</p> <p>In this work, starting from 21 months of data from the <i>Fermi</i> Large Area Telescope (LAT), we derive maps of the residual isotropic γ-ray emission, a relevant fraction of which is expected to be contributed by the extragalactic diffuse γ-ray background (EGB). We search for the auto-correlation signals in the above γ-ray maps and for the <span class="hlt">cross-correlation</span> signal with the angular distribution of different classes of objects that trace the large-scale structure of the Universe. We compute the angular two-point auto-correlation <span class="hlt">function</span> of the residual <i>Fermi</i>-LAT maps at energies E > 1 GeV, E > 3 GeV and E > 30 GeV well above the Galactic plane and find no significant correlation signal. This is, indeed, what is expected if the EGB were contributed by BL Lacertae (BLLacs), Flat Spectrum Radio Quasars (FSRQs) or star-forming galaxies, since, in this case, the predicted signal is very weak. Then, we search for the Integrated Sachs–Wolfe (ISW) signature by <span class="hlt">cross-correlating</span> the Fermi-LAT maps with the 7-year <i>Wilkinson Microwave Anisotropy Probe</i> (<i>WMAP7</i>) cosmic microwave background map. We find a <span class="hlt">cross-correlation</span> consistent with zero, even though the expected signal is larger than that of the EGB auto-correlation. Lastly, in an attempt to constrain the nature of the γ-ray background, we <span class="hlt">cross-correlate</span> the <i>Fermi</i>-LAT maps with the angular distributions of objects that may contribute to the EGB: quasi-stellar objects (QSOs) in the Sloan Digital Sky Survey Data Release 6 (SDSS-DR6) catalogue, NRAO VLA Sky Survey (NVSS) galaxies, Two Micron All Sky Survey (2MASS) galaxies and Luminous Red Galaxies (LRGs) in the SDSS catalogue. The <span class="hlt">cross-correlation</span> is always consistent with zero, in agreement with theoretical expectations, but we find (with low statistical significance) some interesting features that may indicate that some specific classes of objects contribute to the EGB. A χ<sup>2</sup> analysis confirms that the correlation properties</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA630710','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA630710"><span>An Analytic Model of <span class="hlt">Cross-correlation</span> in a Bottom Bounce Environment</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2016-06-07</p> <p>significantly affected by acoustic multipath. An analytic model has been developed to simulate band-1imited <span class="hlt">cross-correlation</span> for an environment in which...Memorandum An Analytic Model of <span class="hlt">Cross-correlation</span> In a Bottom Bounce Environment Prepared by: ~-f.~_:K’ WalterS. Hauck, III El~ctronics...a Bottom Bounce Environment 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Walter Hauck III; Peter Herstein 5d</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Fract..2350044Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Fract..2350044Y"><span>Multifractal Detrended <span class="hlt">Cross-Correlation</span> Analysis for Large-Scale Warehouse-Out Behaviors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yao, Can-Zhong; Lin, Ji-Nan; Zheng, Xu-Zhou</p> <p>2015-09-01</p> <p>Based on <span class="hlt">cross-correlation</span> algorithm, we analyze the correlation property of warehouse-out quantity of different warehouses, respectively, and different products of each warehouse. Our study identifies that significant <span class="hlt">cross-correlation</span> relationship for warehouse-out quantity exists among different warehouses and different products of a warehouse. Further, we take multifractal detrended <span class="hlt">cross-correlation</span> analysis for warehouse-out quantity among different warehouses and different products of a warehouse. The results show that for the warehouse-out behaviors of total amount, different warehouses and different products of a warehouse significantly follow multifractal property. Specifically for each warehouse, the coupling relationships of rebar and wire rod reveal long-term memory characteristics, no matter for large fluctuation or small one. The <span class="hlt">cross-correlation</span> effect on long-range memory property among warehouses probably has less to do with product types,and the long-term memory of YZ warehouse is greater than others especially in total amount and wire rod product. Finally, we shuffle and surrogate data to explore the source of multifractal <span class="hlt">cross-correlation</span> property in logistics system. Taking the total amount of warehouse-out quantity as example, we confirm that the fat-tail distribution of warehouse-out quantity sequences is the main factor for multifractal <span class="hlt">cross-correlation</span>. Through comparing the performance of the multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA), centered multifractal detrending moving average <span class="hlt">cross-correlation</span> analysis (MF-X-DMA) algorithms, the forward and backward MF-X-DMA algorithms, we find that the forward and backward MF-X-DMA algorithms exhibit a better performance than the other ones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4021134','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4021134"><span>The role of executive <span class="hlt">function</span> in children's source monitoring with varying <span class="hlt">retrieval</span> strategies</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Earhart, Becky; Roberts, Kim P.</p> <p>2014-01-01</p> <p>Previous research on the relationship between executive <span class="hlt">function</span> and source monitoring in young children has been inconclusive, with studies finding conflicting results about whether working memory and inhibitory control are related to source-monitoring ability. In this study, the role of working memory and inhibitory control in recognition memory and source monitoring with two different <span class="hlt">retrieval</span> strategies were examined. Children (N = 263) aged 4–8 participated in science activities with two sources. They were later given a recognition and source-monitoring test, and completed measures of working memory and inhibitory control. During the source-monitoring test, half of the participants were asked about sources serially (one after the other) whereas the other half of the children were asked about sources in parallel (considering both sources simultaneously). Results demonstrated that working memory was a predictor of source-monitoring accuracy in both conditions, but inhibitory control was only related to source accuracy in the parallel condition. When age was controlled these relationships were no longer significant, suggesting that a more general cognitive development factor is a stronger predictor of source monitoring than executive <span class="hlt">function</span> alone. Interestingly, the children aged 4–6 years made more accurate source decisions in the parallel condition than in the serial condition. The older children (aged 7–8) were overall more accurate than the younger children, and their accuracy did not differ as a <span class="hlt">function</span> of interview condition. Suggestions are provided to guide further research in this area that will clarify the diverse results of previous studies examining whether executive <span class="hlt">function</span> is a cognitive prerequisite for effective source monitoring. PMID:24847302</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4757146','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4757146"><span><span class="hlt">Functional</span> outcomes and recanalization rates of stent <span class="hlt">retrievers</span> in acute ischaemic stroke: A systematic review and meta-analysis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mizzi, Adrian; Pullicino, Richard; Thornton, John; Downer, Jonathan</p> <p>2015-01-01</p> <p>Background and purpose Intra-arterial therapy for acute ischaemic stroke has evolved rapidly in the last few years. Stent <span class="hlt">retrievers</span> have now replaced ‘first-generation’ devices, which have been the principle devices tested in stroke trials. Our aims were to determine the rates of successful recanalization and <span class="hlt">functional</span> independence in acute stroke patients treated with stent <span class="hlt">retrievers</span>. We also sought to assess the safety outcomes of stent <span class="hlt">retrievers</span> by assessing the rates of mortality and intra-cranial haemorrhage. Materials and methods We conducted a systematic review and meta-analysis of studies which utilized stent <span class="hlt">retrievers</span> as sole treatment or as part of a multi-modal approach in acute ischaemic stroke. Results We identified 20 eligible studies: 17 on Solitaire (ev3/Covidien, Irvine, California, USA) (n = 762) and three on Trevo (Stryker, Kalamazoo, Michigan, USA) (n = 210). The mean age of participants was 66.8 (range 62.1–73.0) years and the M:F ratio was 1.1:1. The average stroke severity score (National Institutes of Health Stroke Scale (NIHSS)) at presentation was 17.2. The weighted mean symptom onset to arterial puncture and procedural duration were 265.4 minutes and 54.8 minutes, respectively. Successful recanalization was achieved in 84.5% of patients with a weighted mean of 2.0 stent <span class="hlt">retriever</span> passes. Independent <span class="hlt">functional</span> outcome was achieved in 51.2% and the mortality rate was 16.8%. Conclusion Stent <span class="hlt">retrievers</span> have the potential to achieve a high rate of recanalization and <span class="hlt">functional</span> independence whilst being relatively safe. They should be assessed in well-designed randomized controlled trials to determine their efficacy and assess whether they compare favourably with ‘standard treatment’ in stroke. PMID:26156097</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=cattells+AND+culture+AND+fair+AND+test&id=EJ765011','ERIC'); return false;" href="http://eric.ed.gov/?q=cattells+AND+culture+AND+fair+AND+test&id=EJ765011"><span>Aging and Strategic <span class="hlt">Retrieval</span> in a Cued-Recall Test: The Role of Executive <span class="hlt">Functions</span> and Fluid Intelligence</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Taconnat, Laurence; Clarys, David; Vanneste, Sandrine; Bouazzaoui, Badiaa; Isingrini, Michel</p> <p>2007-01-01</p> <p>Cued-recall in episodic memory was investigated in relation to low and high cognitive support at <span class="hlt">retrieval</span>, executive <span class="hlt">function</span> level and fluid intelligence level in 81 healthy adults divided first into two age groups (young and elderly adults). The first analyses showed that age-related differences were greater when a low cognitive support was…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810006040','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810006040"><span>Evaluation of atmospheric density models and preliminary <span class="hlt">functional</span> specifications for the Langley Atmospheric Information <span class="hlt">Retrieval</span> System (LAIRS)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lee, T.; Boland, D. F., Jr.</p> <p>1980-01-01</p> <p>This document presents the results of an extensive survey and comparative evaluation of current atmosphere and wind models for inclusion in the Langley Atmospheric Information <span class="hlt">Retrieval</span> System (LAIRS). It includes recommended models for use in LAIRS, estimated accuracies for the recommended models, and <span class="hlt">functional</span> specifications for the development of LAIRS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20637787','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20637787"><span>Hippocampal-neocortical networks differ during encoding and <span class="hlt">retrieval</span> of relational memory: <span class="hlt">functional</span> and effective connectivity analyses.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>McCormick, C; Moscovitch, M; Protzner, A B; Huber, C G; McAndrews, M P</p> <p>2010-09-01</p> <p>Encoding and <span class="hlt">retrieval</span> of relational information requires interaction between the hippocampus and various neocortical regions, but it is unknown whether the connectivity of hippocampal-neocortical networks is different at input and output stages. To examine this, we conducted a network analysis of event-related fMRI data collected during a face-recognition, remember/know paradigm. Directed analyses in the medial temporal lobe identified a small region in the left hippocampus that showed differential activation for encoding and <span class="hlt">retrieval</span> of recollected versus familiar items. Multivariate seed partial least squares (PLS) analysis was used to identify brain regions that were <span class="hlt">functionally</span> connected to this hippocampal region at encoding and <span class="hlt">retrieval</span> of 'remembered' items. Anatomically based structural equation modeling (SEM) was then used to test for differences in effective connectivity of network nodes between these two memory stages. The SEM analysis revealed a reversal of directionality between the left hippocampus (LHC) and left inferior parietal cortex (LIPC) at encoding and <span class="hlt">retrieval</span>. During encoding, activation of the LHC had a positive influence on the LIPC, whereas during <span class="hlt">retrieval</span> the reverse pattern was found, i.e., the LIPC activation positively influenced LHC activation. These findings emphasize the importance of hippocampal-parietal connections and underscore the complexity of their interactions in initial binding and <span class="hlt">retrieval</span>/reintegration of relational memory. We also found that, during encoding, the right hippocampus had a positive influence on the right retrospenial cortex, whereas during <span class="hlt">retrieval</span> this influence was significantly weaker. We submit that examining patterns of connectivity can be important both to elaborate and constrain models of memory involving hippocampal-neocortical interactions. Copyright 2010 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017CNSNS..50..193K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017CNSNS..50..193K"><span>Fractal approach towards power-law coherency to measure <span class="hlt">cross-correlations</span> between time series</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kristoufek, Ladislav</p> <p>2017-09-01</p> <p>We focus on power-law coherency as an alternative approach towards studying power-law <span class="hlt">cross-correlations</span> between simultaneously recorded time series. To be able to study empirical data, we introduce three estimators of the power-law coherency parameter Hρ based on popular techniques usually utilized for studying power-law <span class="hlt">cross-correlations</span> - detrended <span class="hlt">cross-correlation</span> analysis (DCCA), detrending moving-average <span class="hlt">cross-correlation</span> analysis (DMCA) and height <span class="hlt">cross-correlation</span> analysis (HXA). In the finite sample properties study, we focus on the bias, variance and mean squared error of the estimators. We find that the DMCA-based method is the safest choice among the three. The HXA method is reasonable for long time series with at least 104 observations, which can be easily attainable in some disciplines but problematic in others. The DCCA-based method does not provide favorable properties which even deteriorate with an increasing time series length. The paper opens a new venue towards studying <span class="hlt">cross-correlations</span> between time series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S43A4528W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S43A4528W"><span>Pre-Processing and <span class="hlt">Cross-Correlation</span> Techniques for Time-Distance Helioseismology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, N.; de Ridder, S.; Zhao, J.</p> <p>2014-12-01</p> <p>In chaotic wave fields excited by a random distribution of noise sources a <span class="hlt">cross-correlation</span> of the recordings made at two stations yield the interstation wave-field response. After early successes in helioseismology, laboratory studies and earth-seismology, this technique found broad application in global and regional seismology. This development came with an increasing understanding of pre-processing and <span class="hlt">cross-correlation</span> workflows to yield an optimal signal-to-noise ratio (SNR). Helioseismologist rely heavily on stacking to increase the SNR. Until now, they have not studied different spectral-whitening and <span class="hlt">cross-correlation</span> workflows and relies heavily on stacking to increase the SNR. The recordings vary considerably between sunspots and regular portions of the sun. Within the sunspot the periodic effects of the observation satellite orbit are difficult to remove. We remove a running alpha-mean from the data and apply a soft clip to deal with data glitches. The recordings contain energy of both flow and waves. A frequency domain filter selects the wave energy. Then the data is input to several pre-processing and <span class="hlt">cross-correlation</span> techniques, common to earth seismology. We anticipate that spectral whitening will flatten the energy spectrum of the <span class="hlt">cross-correlations</span>. We also expect that the <span class="hlt">cross-correlations</span> converge faster to their expected value when the data is processed over overlapping windows. The result of this study are expected to aid in decreasing the stacking while maintaining good SNR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..486..168L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..486..168L"><span><span class="hlt">Cross-correlations</span> between RMB exchange rate and international commodity markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lu, Xinsheng; Li, Jianfeng; Zhou, Ying; Qian, Yubo</p> <p>2017-11-01</p> <p>This paper employs multifractal detrended analysis (MF-DFA) and multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA) to study <span class="hlt">cross-correlation</span> behaviors between China's RMB exchange rate market and four international commodity markets, using a comprehensive set of data covering the period from 22 July 2005 to 15 March 2016. Our empirical results from MF-DFA indicate that the RMB exchange rate is the most inefficient among the 4 selected markets. The results from quantitative analysis have testified the existence of <span class="hlt">cross-correlations</span> and the result from MF-DCCA have further confirmed a strong multifractal behavior between RMB exchange rate and international commodity markets. We also demonstrate that the recent financial crisis has significant impact on the <span class="hlt">cross-correlated</span> behavior. Through the rolling window analysis, we find that the RMB exchange rates and international commodity prices are anti-persistent <span class="hlt">cross-correlated</span>. The main sources of multifractality in the <span class="hlt">cross-correlations</span> are long-range correlations between RMB exchange rate and the aggregate commodity, energy and metals index.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ApSS..256.3503P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ApSS..256.3503P"><span>Investigation of interface roughness <span class="hlt">cross-correlation</span> properties of optical thin films from total scattering losses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pan, Yongqiang; Wu, Zhensen; Hang, Lingxia</p> <p>2010-03-01</p> <p>The interface roughness and interface roughness <span class="hlt">cross-correlation</span> properties affect the scattering losses of high-quality optical thin films. In this paper, the theoretical models of light scattering induced by surface and interface roughness of optical thin films are concisely presented. Furthermore, influence of interface roughness <span class="hlt">cross-correlation</span> properties to light scattering is analyzed by total scattering losses. Moreover, single-layer TiO 2 thin film thickness, substrate roughness of K9 glass and ion beam assisted deposition (IBAD) technique effect on interface roughness <span class="hlt">cross-correlation</span> properties are studied by experiments, respectively. A 17-layer dielectric quarter-wave high reflection multilayer is analyzed by total scattering losses. The results show that the interface roughness <span class="hlt">cross-correlation</span> properties depend on TiO 2 thin film thickness, substrate roughness and deposition technique. The interface roughness <span class="hlt">cross-correlation</span> properties decrease with the increase of film thickness or the decrease of substrates roughness. Furthermore, ion beam assisted deposition technique can increase the interface roughness <span class="hlt">cross-correlation</span> properties of optical thin films. The measured total scattering losses of 17-layer dielectric quarter-wave high reflection multilayer deposited with IBAD indicate that completely correlated interface model can be observed, when substrate roughness is about 2.84 nm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..463..139R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..463..139R"><span>The exceedance and <span class="hlt">cross-correlations</span> between the gold spot and futures markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruan, Qingsong; Huang, Ying; Jiang, Wei</p> <p>2016-12-01</p> <p>This paper investigates the dynamic features of <span class="hlt">cross-correlations</span> and exceedance correlations between COMEX gold spot and futures returns using the detrended <span class="hlt">cross-correlation</span> analysis (DCCA) and a test for symmetrical exceedance correlation. First, we examine the <span class="hlt">cross-correlations</span> both qualitatively and quantitatively by employing the <span class="hlt">cross-correlations</span> test and the DCCA method. We find that the <span class="hlt">cross-correlations</span> are significant for all lagged orders and are weakly persistent. Our results from a rolling sample test also show that some exogenous events can apparently affect the <span class="hlt">cross-correlations</span> between gold spot and futures returns. Second, after employing the test statistic, our empirical results show that the exceedance correlations between spot and futures returns are both positive and symmetric, indicating that the two returns co-move in the same direction and that the correlations between them are symmetrical for the upper and lower of the returns. However, the results from the rolling sample show that occasional events can induce significant asymmetries of exceedance correlations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvD..95d3530H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvD..95d3530H"><span>Measuring cosmic velocities with 21 cm intensity mapping and galaxy redshift survey <span class="hlt">cross-correlation</span> dipoles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hall, Alex; Bonvin, Camille</p> <p>2017-02-01</p> <p>We investigate the feasibility of measuring the effects of peculiar velocities in large-scale structure using the dipole of the redshift-space <span class="hlt">cross-correlation</span> <span class="hlt">function</span>. We combine number counts of galaxies with brightness-temperature fluctuations from 21 cm intensity mapping, demonstrating that the dipole may be measured at modest significance (≲2 σ ) by combining the upcoming radio survey Canadian Hydrogen Intensity Mapping Experiment with the future redshift surveys of Dark Energy Spectroscopic Instrument (DESI) and Euclid. More significant measurements (≲10 σ ) will be possible by combining intensity maps from the Square Kilometre Array (SKA) with these of DESI or Euclid, and an even higher significance measurement (≲100 σ ) may be made by combining observables completely internally to the SKA. We account for effects such as contamination by wide-angle terms, interferometer noise and beams in the intensity maps, nonlinear enhancements to the power spectrum, stacking multiple populations, sensitivity to the magnification slope, and the possibility that number counts and intensity maps probe the same tracers. We also derive a new expression for the covariance matrix of multitracer redshift-space correlation <span class="hlt">function</span> estimators with arbitrary orientation weights, which may be useful for upcoming surveys aiming at measuring redshift-space clustering with multiple tracers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120014443','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120014443"><span>Method for utilizing properties of the sinc(x) <span class="hlt">function</span> for phase <span class="hlt">retrieval</span> on nyquist-under-sampled data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dean, Bruce H. (Inventor); Smith, Jeffrey Scott (Inventor); Aronstein, David L. (Inventor)</p> <p>2012-01-01</p> <p>Disclosed herein are systems, methods, and non-transitory computer-readable storage media for simulating propagation of an electromagnetic field, performing phase <span class="hlt">retrieval</span>, or sampling a band-limited <span class="hlt">function</span>. A system practicing the method generates transformed data using a discrete Fourier transform which samples a band-limited <span class="hlt">function</span> f(x) without interpolating or modifying received data associated with the <span class="hlt">function</span> f(x), wherein an interval between repeated copies in a periodic extension of the <span class="hlt">function</span> f(x) obtained from the discrete Fourier transform is associated with a sampling ratio Q, defined as a ratio of a sampling frequency to a band-limited frequency, and wherein Q is assigned a value between 1 and 2 such that substantially no aliasing occurs in the transformed data, and <span class="hlt">retrieves</span> a phase in the received data based on the transformed data, wherein the phase is used as feedback to an optical system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AAS...211.5503L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AAS...211.5503L"><span><span class="hlt">Cross</span> <span class="hlt">Correlation</span> between Ly-break Galaxies and Damped Lyα Systems in Cosmological SPH Simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Tae Song; Nagamine, K.</p> <p>2007-12-01</p> <p>We calculate the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> (CCF) between damped Ly-α systems (DLAs) and Lyman break galaxies (LBGs) using cosmological hydrodynamic simulations at z=3. We compute the CCF in two different methods. First, we assume that there is one DLA in each dark matter halo. Second approach is the cross-section-weighted CCF using the direct simulation result of DLA cross section for each halo. We find that the cross-section-weighted CCF gives a steeper γ than the unweighted one, and agrees well with the result of Cooke et al. (2006). Finally, we compute angular CCF for direct comparison with observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.207.1630L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.207.1630L"><span>Frequency domain analysis of errors in <span class="hlt">cross-correlations</span> of ambient seismic noise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Xin; Ben-Zion, Yehuda; Zigone, Dimitri</p> <p>2016-12-01</p> <p>We analyse random errors (variances) in <span class="hlt">cross-correlations</span> of ambient seismic noise in the frequency domain, which differ from previous time domain methods. Extending previous theoretical results on ensemble averaged cross-spectrum, we estimate confidence interval of stacked cross-spectrum of finite amount of data at each frequency using non-overlapping windows with fixed length. The extended theory also connects amplitude and phase variances with the variance of each complex spectrum value. Analysis of synthetic stationary ambient noise is used to estimate the confidence interval of stacked cross-spectrum obtained with different length of noise data corresponding to different number of evenly spaced windows of the same duration. This method allows estimating Signal/Noise Ratio (SNR) of noise <span class="hlt">cross-correlation</span> in the frequency domain, without specifying filter bandwidth or signal/noise windows that are needed for time domain SNR estimations. Based on synthetic ambient noise data, we also compare the probability distributions, causal part amplitude and SNR of stacked cross-spectrum <span class="hlt">function</span> using one-bit normalization or pre-whitening with those obtained without these pre-processing steps. Natural continuous noise records contain both ambient noise and small earthquakes that are inseparable from the noise with the existing pre-processing steps. Using probability distributions of random cross-spectrum values based on the theoretical results provides an effective way to exclude such small earthquakes, and additional data segments (outliers) contaminated by signals of different statistics (e.g. rain, cultural noise), from continuous noise waveforms. This technique is applied to constrain values and uncertainties of amplitude and phase velocity of stacked noise cross-spectrum at different frequencies, using data from southern California at both regional scale (˜35 km) and dense linear array (˜20 m) across the plate-boundary faults. A block bootstrap resampling method</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001JGR...10611957N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001JGR...10611957N"><span>Characterization and field use of a CCD camera system for <span class="hlt">retrieval</span> of bidirectional reflectance distribution <span class="hlt">function</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nandy, P.; Thome, K.; Biggar, S.</p> <p>2001-06-01</p> <p>Vicarious calibration and field validation is a critical aspect of NASA's Earth Observing System program. As part of calibration and validation research related to this project, the Remote Sensing Group (RSG) of the Optical Science Center at the University of Arizona has developed an imaging radiometer for ground-based measurements of directional reflectance. The system relies on a commercially available 1024×1024 pixel, silicon CCD array. Angular measurements are accomplished using a fish-eye lens that has a full 180° field of view with each pixel on the CCD array having a nominal 0.2° field of view. Spectral selection is through four interference filters centered at 470, 575, 660, and 835 nm. The system is designed such that the entire 180° field is collected at one time with a complete multispectral data set collected in under 2 min. The results of laboratory experiments have been used to determine the gain and offset of each detector element as well as the effects of the lens on the system response. Measurements of a stable source using multiple integration times and at multiple distances for a set integration time indicate the system is linear to better than 0.5% over the upper 88% of the dynamic range of the system. The point spread <span class="hlt">function</span> (PSF) of the lens system was measured for several field angles, and the signal level was found to fall to less than 1% of the peak signal within 1.5° for the on-axis case. The effect of this PSF on the <span class="hlt">retrieval</span> of modeled BRDFs is shown to be less than 0.2% out to view angles of 70°. The degree of polarization of the system is shown to be negligible for on-axis imaging but to have up to a 20% effect at a field angle of 70°. The effect of the system polarization on the <span class="hlt">retrieval</span> of modeled BRDFs is shown to be up to 3% for field angles of 70° off nadir and with a solar zenith angle of 70°. Field measurements are made by mounting the camera to a boom mounted to a large tripod that is aligned toward south. This</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18238424','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18238424"><span>Interpolation methods for time-delay estimation using <span class="hlt">cross-correlation</span> method for blood velocity measurement.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lai, X; Torp, H</p> <p>1999-01-01</p> <p>The <span class="hlt">cross-correlation</span> method (CCM) for blood flow velocity measurement using Doppler ultrasound is based on time delay estimation of echoes from pulse-to-pulse. The sampling frequency of the received signal is usually kept as low as possible in order to reduce computational complexity, and the peak in the correlation <span class="hlt">function</span> is found by interpolating the correlation <span class="hlt">function</span>. The parabolic-fit interpolation method introduces a bias at low sampling rate to the ultrasound center frequency ratio. In this study, four different methods are suggested to improve the estimation accuracy: (1) Parabolic interpolation with bias-compensation, derived from a theoretical signal model. (2) Parabolic interpolation combined with linear filter interpolation of the correlation <span class="hlt">function</span>. (3) Parabolic interpolation to the complex correlation <span class="hlt">function</span> envelope. (4) Matched filter interpolation applied to the correlation <span class="hlt">function</span>. The new interpolation methods are analyzed both by computer simulated signals and RF-signals recorded from a patient with time delay larger than 1/f(0), where f(0) is the center frequency. The simulation results show that these methods are more accurate than the parabolic-fit method. From the simulation, the worst estimation accuracy is about 1.25% of 1/f(0) for the parabolic-fit interpolation, and it is improved by the above methods to less than 0.5% of 1/f(0) when the sampling rate is 10 MHz, the center frequency is 2.5 MHz and the bandwidth is 1 MHz. This improvement also can be observed in the experimental data. Furthermore, the matched filter interpolation gives the best performance when signal-to-noise ratio (SNR) is low. This is verified both by simulation and experimentation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..472...67C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..472...67C"><span>Volatility-constrained multifractal detrended <span class="hlt">cross-correlation</span> analysis: <span class="hlt">Cross-correlation</span> among Mainland China, US, and Hong Kong stock markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cao, Guangxi; Zhang, Minjia; Li, Qingchen</p> <p>2017-04-01</p> <p>This study focuses on multifractal detrended <span class="hlt">cross-correlation</span> analysis of the different volatility intervals of Mainland China, US, and Hong Kong stock markets. A volatility-constrained multifractal detrended <span class="hlt">cross-correlation</span> analysis (VC-MF-DCCA) method is proposed to study the volatility conductivity of Mainland China, US, and Hong Kong stock markets. Empirical results indicate that fluctuation may be related to important activities in real markets. The Hang Seng Index (HSI) stock market is more influential than the Shanghai Composite Index (SCI) stock market. Furthermore, the SCI stock market is more influential than the Dow Jones Industrial Average stock market. The conductivity between the HSI and SCI stock markets is the strongest. HSI was the most influential market in the large fluctuation interval of 1991 to 2014. The autoregressive fractionally integrated moving average method is used to verify the validity of VC-MF-DCCA. Results show that VC-MF-DCCA is effective.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.466.3558M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.466.3558M"><span>A joint analysis for cosmology and photometric redshift calibration using <span class="hlt">cross-correlations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McLeod, Michael; Balan, Sreekumar T.; Abdalla, Filipe B.</p> <p>2017-04-01</p> <p>We present a method of calibrating the properties of photometric redshift bins as part of a larger nested sampling analysis for the inference of cosmological parameters. The redshift bins are characterized by their mean and variance, which are varied as free parameters and marginalized over when obtaining the cosmological parameters. We demonstrate that the likelihood <span class="hlt">function</span> for <span class="hlt">cross-correlations</span> in an angular power spectrum framework tightly constrains the properties of bins such that they may be well determined, reducing their influence on cosmological parameters and avoiding the bias from poorly estimated redshift distributions. We demonstrate that even with only three photometric and three spectroscopic bins, we can recover accurate estimates of the mean redshift of a bin to within Δμ ≈ 3-4 × 10-3 and the width of the bin to Δσ ≈ 1 × 10-3 for galaxies near z = 1. This indicates that we may be able to bring down the photometric redshift errors to a level which is in line with the requirements for the next generation of cosmological experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/917269','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/917269"><span><span class="hlt">Cross-correlation</span> Weak Lensing of SDSS Galaxy Clusters I: Measurements</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sheldon, Erin S.; Johnston, David E.; Scranton, Ryan; Koester, Ben P.; McKay, Timothy A.; Oyaizu, Hiroaki; Cunha, Carlos; Lima, Marcos; Lin, Huan; Frieman, Joshua A.; Wechsler, Risa H.; Annis, James; Mandelbaum, Rachel; Bahcall, Neta A.; Fukugita, Masataka</p> <p>2007-09-28</p> <p>This is the first in a series of papers on the weak lensing effect caused by clusters of galaxies in Sloan Digital Sky Survey. The photometrically selected cluster sample, known as MaxBCG, includes {approx}130,000 objects between redshift 0.1 and 0.3, ranging in size from small groups to massive clusters. We split the clusters into bins of richness and luminosity and stack the surface density contrast to produce mean radial profiles. The mean profiles are detected over a range of scales, from the inner halo (25 kpc/h) well into the surrounding large scale structure (30 Mpc/h), with a significance of 15 to 20 in each bin. The signal over this large range of scales is best interpreted in terms of the cluster-mass <span class="hlt">cross-correlation</span> <span class="hlt">function</span>. We pay careful attention to sources of systematic error, correcting for them where possible and bounding them where not. We find that the profiles scale strongly with richness and luminosity. We find the signal within a given richness bin depends upon luminosity, suggesting that luminosity is more closely correlated with mass than galaxy counts. We split the samples by redshift but detect no significant evolution. The profiles are not well described by power laws. In a subsequent series of papers we invert the profiles to three-dimensional mass profiles, show that they are well fit by a halo model description, measure mass-to-light ratios and provide a cosmological interpretation.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3274287','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3274287"><span>Measuring Time-of-Flight in an Ultrasonic LPS System Using Generalized <span class="hlt">Cross-Correlation</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Villladangos, José Manuel; Ureña, Jesús; García, Juan Jesús; Mazo, Manuel; Hernández, Álvaro; Jiménez, Ana; Ruíz, Daniel; De Marziani, Carlos</p> <p>2011-01-01</p> <p>In this article, a time-of-flight detection technique in the frequency domain is described for an ultrasonic Local Positioning System (LPS) based on encoded beacons. Beacon transmissions have been synchronized and become simultaneous by means of the DS-CDMA (Direct-Sequence Code Division Multiple Access) technique. Every beacon has been associated to a 255-bit Kasami code. The detection of signal arrival instant at the receiver, from which the distance to each beacon can be obtained, is based on the application of the Generalized <span class="hlt">Cross-Correlation</span> (GCC), by using the cross-spectral density between the received signal and the sequence to be detected. Prior filtering to enhance the frequency components around the carrier frequency (40 kHz) has improved estimations when obtaining the correlation <span class="hlt">function</span> maximum, which implies an improvement in distance measurement precision. Positioning has been achieved by using hyperbolic trilateration, based on the Time Differences of Arrival (TDOA) between a reference beacon and the others. PMID:22346645</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMIN21B3702J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMIN21B3702J"><span>Pipeline Implementation of Real Time Event <span class="hlt">Cross</span> <span class="hlt">Correlation</span> for Nuclear Treaty Monitoring</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Junek, W. N.; Wehlen, J. A., III</p> <p>2014-12-01</p> <p>The United States National Data Center (US NDC) is responsible for monitoring international compliance to nuclear test ban treaties. This mission is performed through real time acquisition, processing, and evaluation of data acquired by a global network of seismic, hydroacoustic, and infrasonic sensors. Automatic and human reviewed event solutions are stored in a data warehouse which contains over 15 years of alphanumeric information and waveform data. A significant effort is underway to employ the data warehouse in real time processing to improve the quality of automatic event solutions, reduce analyst burden, and supply decision makers with information regarding relevant historic events. To this end, the US NDC processing pipeline has been modified to automatically recognize events built in the past. Event similarity information and the most relevant historic solution are passed to the human analyst to assist their evaluation of automatically formed events. This is achieved through real time <span class="hlt">cross</span> <span class="hlt">correlation</span> of selected seismograms from automatically formed events against those stored in the data warehouse. Historic events used in correlation analysis are selected based on a set of user defined parameters, which are tuned to maintain pipeline timeliness requirements. Software architecture and database infrastructure were modified using a multithreaded design for increased processing speed, database connection pools for parallel queries, and Oracle spatial indexing to enhance query efficiency. This <span class="hlt">functionality</span> allows the human analyst to spend more time studying anomalous events and less time rebuilding routine events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22525359','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22525359"><span>Probing the diffuse baryon distribution with the lensing-tSZ <span class="hlt">cross-correlation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ma, Yin-Zhe; Zuntz, Joe; Waerbeke, Ludovic Van; Hinshaw, Gary; Hojjati, Alireza; Scott, Douglas E-mail: waerbeke@phas.ubc.ca E-mail: ahojjati@phas.ubc.ca E-mail: joezuntz@googlemail.com</p> <p>2015-09-01</p> <p>Approximately half of the Universe's baryons are in a form that has been hard to detect directly. However, the missing component can be traced through the <span class="hlt">cross-correlation</span> of the thermal Sunyaev-Zeldovich (tSZ) effect with weak gravitational lensing. We build a model for this correlation and use it to constrain the extended baryon component, employing data from the Canada France Hawaii Lensing Survey and the Planck satellite. The measured correlation <span class="hlt">function</span> is consistent with an isothermal β-model for the halo gas pressure profile, and the 1- and 2-halo terms are both detected at the 4σ level. In addition, we measure the hydrostatic mass bias (1−b)=0.79{sup +0.07}{sub −0.10}, which is consistent with numerical simulation results and the constraints from X-ray observations. The effective temperature of the gas is found to be in the range (7×10{sup 5}–3 ×10{sup 8}) K, with approximately 50% of the baryons appearing to lie beyond the virial radius of the halos, consistent with current expectations for the warm-hot intergalactic medium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JSV...386...82P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JSV...386...82P"><span>Acoustic source localization using a polyhedral microphone array and an improved generalized <span class="hlt">cross-correlation</span> technique</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Padois, Thomas; Sgard, Franck; Doutres, Olivier; Berry, Alain</p> <p>2017-01-01</p> <p>Millions of workers are exposed to excessive noise levels each day. Acoustic solutions have to be developed to protect workers from hearing loss. The first step of an acoustic diagnosis is the source localization which can be performed with a microphone array. Spherical microphone arrays can be used to detect the acoustic source positions in a workplace. In this study, a spherical microphone array, with polyhedral discretization, is proposed and compared with a spherical array with a slightly different geometry. The generalized <span class="hlt">cross-correlation</span> technique is used to detect the source positions. Moreover, two criteria are introduced to improve the noise source map. The first is based on the geometric properties of the microphone array and the scan zone whereas the second is based on the energy of the spatial likelihood <span class="hlt">function</span>. Numerical data are used to provide a systematic comparison of both geometries and criteria. Finally, experiments in a reverberant room reveal that the polyhedral microphone array associated with both criteria provides the best noise source map.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013OptLE..51..929L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013OptLE..51..929L"><span>Experimental <span class="hlt">cross-correlation</span> nitrogen Q-branch CARS thermometry in a spark ignition engine</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lockett, R. D.; Ball, D.; Robertson, G. N.</p> <p>2013-07-01</p> <p>A purely experimental technique was employed to derive temperatures from nitrogen Q-branch Coherent Anti-Stokes Raman Scattering (CARS) spectra, obtained in a high pressure, high temperature environment (spark ignition Otto engine). This was in order to obviate any errors arising from deficiencies in the spectral scaling laws which are commonly used to represent nitrogen Q-branch CARS spectra at high pressure. The spectra obtained in the engine were compared with spectra obtained in a calibrated high pressure, high temperature cell, using direct <span class="hlt">cross-correlation</span> in place of the minimisation of sums of squares of residuals. The technique is demonstrated through the measurement of air temperature as a <span class="hlt">function</span> of crankshaft angle inside the cylinder of a motored single-cylinder Ricardo E6 research engine, followed by the measurement of fuel-air mixture temperatures obtained during the compression stroke in a knocking Ricardo E6 engine. A standard CARS programme (SANDIA's CARSFIT) was employed to calibrate the altered non-resonant background contribution to the CARS spectra that was caused by the alteration to the mole fraction of nitrogen in the unburned fuel-air mixture. The compression temperature profiles were extrapolated in order to predict the auto-ignition temperatures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2215067','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2215067"><span>Finding Leading Indicators for Disease Outbreaks: Filtering, <span class="hlt">Cross-correlation</span>, and Caveats</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bloom, Ronald M.; Buckeridge, David L.; Cheng, Karen E.</p> <p>2007-01-01</p> <p>Bioterrorism and emerging infectious diseases such as influenza have spurred research into rapid outbreak detection. One primary thrust of this research has been to identify data sources that provide early indication of a disease outbreak by being leading indicators relative to other established data sources. Researchers tend to rely on the sample <span class="hlt">cross-correlation</span> <span class="hlt">function</span> (CCF) to quantify the association between two data sources. There has been, however, little consideration by medical informatics researchers of the influence of methodological choices on the ability of the CCF to identify a lead–lag relationship between time series. We draw on experience from the econometric and environmental health communities, and we use simulation to demonstrate that the sample CCF is highly prone to bias. Specifically, long-scale phenomena tend to overwhelm the CCF, obscuring phenomena at shorter wave lengths. Researchers seeking lead–lag relationships in surveillance data must therefore stipulate the scale length of the features of interest (e.g., short-scale spikes versus long-scale seasonal fluctuations) and then filter the data appropriately—to diminish the influence of other features, which may mask the features of interest. Otherwise, conclusions drawn from the sample CCF of bi-variate time-series data will inevitably be ambiguous and often altogether misleading. PMID:17068353</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MSSP...92..293C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MSSP...92..293C"><span>Increasing the computational efficient of digital <span class="hlt">cross</span> <span class="hlt">correlation</span> by a vectorization method</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chang, Ching-Yuan; Ma, Chien-Ching</p> <p>2017-08-01</p> <p>This study presents a vectorization method for use in MATLAB programming aimed at increasing the computational efficiency of digital <span class="hlt">cross</span> <span class="hlt">correlation</span> in sound and images, resulting in a speedup of 6.387 and 36.044 times compared with performance values obtained from looped expression. This work bridges the gap between matrix operations and loop iteration, preserving flexibility and efficiency in program testing. This paper uses numerical simulation to verify the speedup of the proposed vectorization method as well as experiments to measure the quantitative transient displacement response subjected to dynamic impact loading. The experiment involved the use of a high speed camera as well as a fiber optic system to measure the transient displacement in a cantilever beam under impact from a steel ball. Experimental measurement data obtained from the two methods are in excellent agreement in both the time and frequency domain, with discrepancies of only 0.68%. Numerical and experiment results demonstrate the efficacy of the proposed vectorization method with regard to computational speed in signal processing and high precision in the correlation algorithm. We also present the source code with which to build MATLAB-executable <span class="hlt">functions</span> on Windows as well as Linux platforms, and provide a series of examples to demonstrate the application of the proposed vectorization method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22346645','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22346645"><span>Measuring time-of-flight in an ultrasonic LPS system using generalized <span class="hlt">cross-correlation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Villladangos, José Manuel; Ureña, Jesús; García, Juan Jesús; Mazo, Manuel; Hernández, Alvaro; Jiménez, Ana; Ruíz, Daniel; De Marziani, Carlos</p> <p>2011-01-01</p> <p>In this article, a time-of-flight detection technique in the frequency domain is described for an ultrasonic local positioning system (LPS) based on encoded beacons. Beacon transmissions have been synchronized and become simultaneous by means of the DS-CDMA (direct-sequence code Division multiple access) technique. Every beacon has been associated to a 255-bit Kasami code. The detection of signal arrival instant at the receiver, from which the distance to each beacon can be obtained, is based on the application of the generalized <span class="hlt">cross-correlation</span> (GCC), by using the cross-spectral density between the received signal and the sequence to be detected. Prior filtering to enhance the frequency components around the carrier frequency (40 kHz) has improved estimations when obtaining the correlation <span class="hlt">function</span> maximum, which implies an improvement in distance measurement precision. Positioning has been achieved by using hyperbolic trilateration, based on the time differences of arrival (TDOA) between a reference beacon and the others.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17182162','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17182162"><span>Aging and strategic <span class="hlt">retrieval</span> in a cued-recall test: the role of executive <span class="hlt">functions</span> and fluid intelligence.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Taconnat, Laurence; Clarys, David; Vanneste, Sandrine; Bouazzaoui, Badiâa; Isingrini, Michel</p> <p>2007-06-01</p> <p>Cued-recall in episodic memory was investigated in relation to low and high cognitive support at <span class="hlt">retrieval</span>, executive <span class="hlt">function</span> level and fluid intelligence level in 81 healthy adults divided first into two age groups (young and elderly adults). The first analyses showed that age-related differences were greater when a low cognitive support was provided to recall the words. An individual index of loss of performance when the number of cues was decreased was then calculated. Hierarchical regression analysis revealed that the executive <span class="hlt">functions</span> measure (perseverative errors on the Wisconsin Card Sorting Test) was a better candidate than the fluid intelligence measure (Cattell's culture fair test) to account for the age-related variance of the size of performance loss. These findings suggest that age differences in implementing strategic <span class="hlt">retrieval</span> may be mainly due to a decline in executive <span class="hlt">functions</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23636729','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23636729"><span>Method for stationarity-segmentation of spike train data with application to the Pearson <span class="hlt">cross-correlation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Quiroga-Lombard, Claudio S; Hass, Joachim; Durstewitz, Daniel</p> <p>2013-07-01</p> <p>Correlations among neurons are supposed to play an important role in computation and information coding in the nervous system. Empirically, <span class="hlt">functional</span> interactions between neurons are most commonly assessed by <span class="hlt">cross-correlation</span> <span class="hlt">functions</span>. Recent studies have suggested that pairwise correlations may indeed be sufficient to capture most of the information present in neural interactions. Many applications of correlation <span class="hlt">functions</span>, however, implicitly tend to assume that the underlying processes are stationary. This assumption will usually fail for real neurons recorded in vivo since their activity during behavioral tasks is heavily influenced by stimulus-, movement-, or cognition-related processes as well as by more general processes like slow oscillations or changes in state of alertness. To address the problem of nonstationarity, we introduce a method for assessing stationarity empirically and then "slicing" spike trains into stationary segments according to the statistical definition of weak-sense stationarity. We examine pairwise Pearson <span class="hlt">cross-correlations</span> (PCCs) under both stationary and nonstationary conditions and identify another source of covariance that can be differentiated from the covariance of the spike times and emerges as a consequence of residual nonstationarities after the slicing process: the covariance of the firing rates defined on each segment. Based on this, a correction of the PCC is introduced that accounts for the effect of segmentation. We probe these methods both on simulated data sets and on in vivo recordings from the prefrontal cortex of behaving rats. Rather than for removing nonstationarities, the present method may also be used for detecting significant events in spike trains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.467.2706T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.467.2706T"><span><span class="hlt">Cross-correlation</span> of weak lensing and gamma rays: implications for the nature of dark matter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tröster, Tilman; Camera, Stefano; Fornasa, Mattia; Regis, Marco; van Waerbeke, Ludovic; Harnois-Déraps, Joachim; Ando, Shin'ichiro; Bilicki, Maciej; Erben, Thomas; Fornengo, Nicolao; Heymans, Catherine; Hildebrandt, Hendrik; Hoekstra, Henk; Kuijken, Konrad; Viola, Massimo</p> <p>2017-05-01</p> <p>We measure the <span class="hlt">cross-correlation</span> between Fermi gamma-ray photons and over 1000 deg2 of weak lensing data from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS), the Red Cluster Sequence Lensing Survey (RCSLenS), and the Kilo Degree Survey (KiDS). We present the first measurement of tomographic weak lensing <span class="hlt">cross-correlations</span> and the first application of spectral binning to <span class="hlt">cross-correlations</span> between gamma rays and weak lensing. The measurements are performed using an angular power spectrum estimator while the covariance is estimated using an analytical prescription. We verify the accuracy of our covariance estimate by comparing it to two internal covariance estimators. Based on the non-detection of a <span class="hlt">cross-correlation</span> signal, we derive constraints on weakly interacting massive particle (WIMP) dark matter. We compute exclusion limits on the dark matter annihilation cross-section <σannv>, decay rate Γdec and particle mass mDM. We find that in the absence of a <span class="hlt">cross-correlation</span> signal, tomography does not significantly improve the constraining power of the analysis. Assuming a strong contribution to the gamma-ray flux due to small-scale clustering of dark matter and accounting for known astrophysical sources of gamma rays, we exclude the thermal relic cross-section for particle masses of mDM ≲ 20 GeV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NIMPA.784..460B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NIMPA.784..460B"><span><span class="hlt">Cross-correlation</span> measurements with the EJ-299-33 plastic scintillator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bourne, Mark M.; Whaley, Jeff; Dolan, Jennifer L.; Polack, John K.; Flaska, Marek; Clarke, Shaun D.; Tomanin, Alice; Peerani, Paolo; Pozzi, Sara A.</p> <p>2015-06-01</p> <p>New organic-plastic scintillation compositions have demonstrated pulse-shape discrimination (PSD) of neutrons and gamma rays. We present <span class="hlt">cross-correlation</span> measurements of 252Cf and mixed uranium-plutonium oxide (MOX) with the EJ-299-33 plastic scintillator. For comparison, equivalent measurements were performed with an EJ-309 liquid scintillator. Offline, digital PSD was applied to each detector. These measurements show that EJ-299-33 sacrifices a factor of 5 in neutron-neutron efficiency relative to EJ-309, but could still utilize the difference in neutron-neutron efficiency and neutron single-to-double ratio to distinguish 252Cf from MOX. These measurements were modeled with MCNPX-PoliMi, and MPPost was used to convert the detailed collision history into simulated <span class="hlt">cross-correlation</span> distributions. MCNPX-PoliMi predicted the measured 252Cf <span class="hlt">cross-correlation</span> distribution for EJ-309 to within 10%. Greater photon uncertainty in the MOX sample led to larger discrepancy in the simulated MOX <span class="hlt">cross-correlation</span> distribution. The modeled EJ-299-33 plastic also gives reasonable agreement with measured <span class="hlt">cross-correlation</span> distributions, although the MCNPX-PoliMi model appears to under-predict the neutron detection efficiency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..481...23Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..481...23Y"><span>The <span class="hlt">cross-correlation</span> analysis of multi property of stock markets based on MM-DFA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Yujun; Li, Jianping; Yang, Yimei</p> <p>2017-09-01</p> <p>In this paper, we propose a new method called DH-MXA based on distribution histograms of Hurst surface and multiscale multifractal detrended fluctuation analysis. The method allows us to investigate the <span class="hlt">cross-correlation</span> characteristics among multiple properties of different stock time series. It may provide a new way of measuring the nonlinearity of several signals. It also can provide a more stable and faithful description of <span class="hlt">cross-correlation</span> of multiple properties of stocks. The DH-MXA helps us to present much richer information than multifractal detrented <span class="hlt">cross-correlation</span> analysis and allows us to assess many universal and subtle <span class="hlt">cross-correlation</span> characteristics of stock markets. We show DH-MXA by selecting four artificial data sets and five properties of four stock time series from different countries. The results show that our proposed method can be adapted to investigate the <span class="hlt">cross-correlation</span> of stock markets. In general, the American stock markets are more mature and less volatile than the Chinese stock markets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...846...21F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...846...21F"><span>A Halo Model Approach to the 21 cm and Lyα <span class="hlt">Cross-correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feng, Chang; Cooray, Asantha; Keating, Brian</p> <p>2017-09-01</p> <p>We present a halo-model-based approach to calculate the <span class="hlt">cross-correlation</span> between 21 {cm} H i intensity fluctuations and {Ly}α emitters (LAE) during the epoch of reionization (EoR). Ionizing radiation around dark matter halos are modeled as bubbles with the size and growth determined based on the reionization photon production, among other physical parameters. The <span class="hlt">cross-correlation</span> shows a clear negative-to-positive transition, associated with transition from ionized to neutral hydrogen in the intergalactic medium during EoR. The <span class="hlt">cross-correlation</span> is subject to several foreground contaminants, including foreground radio point sources important for 21 {cm} experiments and low-z interloper emission lines, such as {{H}}α , O iii, and O ii, for {Ly}α experiments. Our calculations show that by masking out high fluxes in the {Ly}α measurement, the correlated foreground contamination on the 21 {cm}–{Ly}α <span class="hlt">cross-correlation</span> can be dramatically reduced. We forecast the detectability of 21 {cm}–{Ly}α <span class="hlt">cross-correlation</span> at different redshifts and adopt a Fisher matrix approach to estimate uncertainties on the key EoR parameters that have not been well constrained by other observations of reionization. This halo-model-based approach enables us to explore the EoR parameter space rapidly for different 21 {cm} and {Ly}α experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPCM...29s5302W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPCM...29s5302W"><span>Current <span class="hlt">cross-correlations</span> in double quantum dot based Cooper pair splitters with ferromagnetic leads</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wrześniewski, Kacper; Trocha, Piotr; Weymann, Ireneusz</p> <p>2017-05-01</p> <p>We investigate the current <span class="hlt">cross-correlations</span> in a double quantum dot based Cooper pair splitter coupled to one superconducting and two ferromagnetic electrodes. The analysis is performed by assuming a weak coupling between the double dot and ferromagnetic leads, while the coupling to the superconductor is arbitrary. Employing the perturbative real-time diagrammatic technique, we study the Andreev transport properties of the device, focusing on the Andreev current <span class="hlt">cross-correlations</span>, for various parameters of the model, both in the linear and nonlinear response regimes. Depending on parameters and transport regime, we find both positive and negative current <span class="hlt">cross-correlations</span>. Enhancement of the former type of <span class="hlt">cross-correlations</span> indicates transport regimes, in which the device works with high Cooper pair splitting efficiency, contrary to the latter type of correlations, which imply negative influence on the splitting. The processes and mechanisms leading to both types of current <span class="hlt">cross-correlations</span> are thoroughly examined and discussed, giving a detailed insight into the Andreev transport properties of the considered device.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23469555','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23469555"><span>[Detrended <span class="hlt">cross-correlation</span> analysis: a new method for gait signal analysis].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Pingping; Wang, Jun</p> <p>2012-12-01</p> <p>The <span class="hlt">cross-correlation</span> of gait signal can mirror the health situations of different people. It is important to analyze the long-range <span class="hlt">cross</span> <span class="hlt">correlations</span> of the two signals of nonstationarity for medical research. In this paper, we propose a detrended <span class="hlt">cross-correlation</span> analysis (DCCA) method for analyzing the different gait signal in physiological and pathological conditions. Our work dealt with three kinds of gait signals, including those of normal young people (23 to 29 years of age), those of healthy old people (71 to 77 years of age) and those of the old people (60 to 77 years of age) with Parkinson's disease from the MIT-BIH database. We carried out the DCCA for the three gait signals of nonstationarity. The results showed that the self-similarity of gait signal got more unstable with the age increasing and health status worsening. From the <span class="hlt">cross-correlation</span> analysis, we found that the <span class="hlt">cross-correlation</span> degree of gait signal of young people increased gradually, the healthy old people changed slowly and the Parkinson's disease patients showed unstable changes. We can make medical diagnosis and treatment according to the differences among different gait signals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhyA..392.5356M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhyA..392.5356M"><span><span class="hlt">Cross-correlations</span> between West Texas Intermediate crude oil and the stock markets of the BRIC</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, Feng; Wei, Yu; Huang, Dengshi; Zhao, Lin</p> <p>2013-11-01</p> <p>In this paper, we investigate the <span class="hlt">cross-correlation</span> properties between West Texas Intermediate crude oil and the stock markets of the BRIC. We use not only the qualitative analysis of the <span class="hlt">cross-correlation</span> test, but also take the quantitative analysis of the MF-DXA, confirming the <span class="hlt">cross-correlation</span> relationship between West Texas Intermediate crude oil and the stock markets of the BRIC (Brazil, Russia, India and China) respectively, which have strongly multifractal features, and the <span class="hlt">cross-correlations</span> are more strongly multifractal in the short term than in the long term. Furthermore, based on the multifractal spectrum, we also find the multifractality strength between the crude oil WTI and Chinese stock market is stronger than the multifractality strength of other pairs. Based on the Iraq war (Mar 20, 2003) and the Financial crisis in 2008, we divide sample period into four segments to research the degree of the multifractal (ΔH) and the market efficiency (and the risk). Finally, we employ the technique of the rolling window to calculate the time-varying EI (efficiency index) and dependent on the EI, we can easily observe the change of stock markets. Furthermore, we explore the relationship between bivariate <span class="hlt">cross-correlation</span> exponents (Hxy(q)) and the generalized Hurst exponents.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22518758','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22518758"><span>DECONSTRUCTING THERMAL SUNYAEV–ZEL’DOVICH—GRAVITATIONAL LENSING <span class="hlt">CROSS-CORRELATIONS</span>: IMPLICATIONS FOR THE INTRACLUSTER MEDIUM</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Battaglia, N.; Hill, J. C.; Murray, N.</p> <p>2015-10-20</p> <p>Recent first detections of the <span class="hlt">cross-correlation</span> of the thermal Sunyaev–Zel’dovich (tSZ) signal in Planck cosmic microwave background (CMB) temperature maps with gravitational lensing maps inferred from the Planck CMB data and the CFHTLenS galaxy survey provide new probes of the relationship between baryons and dark matter. Using cosmological hydrodynamics simulations, we show that these <span class="hlt">cross-correlation</span> signals are dominated by contributions from hot gas in the intracluster medium (ICM), rather than diffuse, unbound gas located beyond the virial radius (the “missing baryons”). Thus, these <span class="hlt">cross-correlations</span> offer a tool with which to study the ICM over a wide range of halo masses and redshifts. In particular, we show that the tSZ—CMB lensing <span class="hlt">cross-correlation</span> is more sensitive to gas in lower-mass, higher-redshift halos and gas at larger cluster-centric radii than the tSZ—galaxy lensing <span class="hlt">cross-correlation</span>. Combining these measurements with primary CMB data will constrain feedback models through their signatures in the ICM pressure profile. We forecast the ability of ongoing and future experiments to constrain the parameters of a phenomenological ICM model, including the mean amplitude of the pressure–mass relation, the redshift evolution of this amplitude, and the mean outer logarithmic slope of the pressure profile. The results are promising, with ≈5%–20% precision constraints achievable with upcoming experiments, even after marginalizing over cosmological parameters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28379841','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28379841"><span>Current <span class="hlt">cross-correlations</span> in double quantum dot based Cooper pair splitters with ferromagnetic leads.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wrześniewski, Kacper; Trocha, Piotr; Weymann, Ireneusz</p> <p>2017-05-17</p> <p>We investigate the current <span class="hlt">cross-correlations</span> in a double quantum dot based Cooper pair splitter coupled to one superconducting and two ferromagnetic electrodes. The analysis is performed by assuming a weak coupling between the double dot and ferromagnetic leads, while the coupling to the superconductor is arbitrary. Employing the perturbative real-time diagrammatic technique, we study the Andreev transport properties of the device, focusing on the Andreev current <span class="hlt">cross-correlations</span>, for various parameters of the model, both in the linear and nonlinear response regimes. Depending on parameters and transport regime, we find both positive and negative current <span class="hlt">cross-correlations</span>. Enhancement of the former type of <span class="hlt">cross-correlations</span> indicates transport regimes, in which the device works with high Cooper pair splitting efficiency, contrary to the latter type of correlations, which imply negative influence on the splitting. The processes and mechanisms leading to both types of current <span class="hlt">cross-correlations</span> are thoroughly examined and discussed, giving a detailed insight into the Andreev transport properties of the considered device.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27809243','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27809243"><span>A <span class="hlt">Cross-Correlational</span> Analysis between Electroencephalographic and End-Tidal Carbon Dioxide Signals: Methodological Issues in the Presence of Missing Data and Real Data Results.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Morelli, Maria Sole; Giannoni, Alberto; Passino, Claudio; Landini, Luigi; Emdin, Michele; Vanello, Nicola</p> <p>2016-10-31</p> <p>Electroencephalographic (EEG) irreducible artifacts are common and the removal of corrupted segments from the analysis may be required. The present study aims at exploring the effects of different EEG Missing Data Segment (MDS) distributions on <span class="hlt">cross-correlation</span> analysis, involving EEG and physiological signals. The reliability of <span class="hlt">cross-correlation</span> analysis both at single subject and at group level as a <span class="hlt">function</span> of missing data statistics was evaluated using dedicated simulations. Moreover, a Bayesian-based approach for combining the single subject results at group level by considering each subject's reliability was introduced. Starting from the above considerations, the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> between EEG Global Field Power (GFP) in delta band and end-tidal CO₂ (PETCO₂) during rest and voluntary breath-hold was evaluated in six healthy subjects. The analysis of simulated data results at single subject level revealed a worsening of precision and accuracy in the <span class="hlt">cross-correlation</span> analysis in the presence of MDS. At the group level, a large improvement in the results' reliability with respect to single subject analysis was observed. The proposed Bayesian approach showed a slight improvement with respect to simple average results. Real data results were discussed in light of the simulated data tests and of the current physiological findings.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5134487','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5134487"><span>A <span class="hlt">Cross-Correlational</span> Analysis between Electroencephalographic and End-Tidal Carbon Dioxide Signals: Methodological Issues in the Presence of Missing Data and Real Data Results</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Morelli, Maria Sole; Giannoni, Alberto; Passino, Claudio; Landini, Luigi; Emdin, Michele; Vanello, Nicola</p> <p>2016-01-01</p> <p>Electroencephalographic (EEG) irreducible artifacts are common and the removal of corrupted segments from the analysis may be required. The present study aims at exploring the effects of different EEG Missing Data Segment (MDS) distributions on <span class="hlt">cross-correlation</span> analysis, involving EEG and physiological signals. The reliability of <span class="hlt">cross-correlation</span> analysis both at single subject and at group level as a <span class="hlt">function</span> of missing data statistics was evaluated using dedicated simulations. Moreover, a Bayesian-based approach for combining the single subject results at group level by considering each subject’s reliability was introduced. Starting from the above considerations, the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> between EEG Global Field Power (GFP) in delta band and end-tidal CO2 (PETCO2) during rest and voluntary breath-hold was evaluated in six healthy subjects. The analysis of simulated data results at single subject level revealed a worsening of precision and accuracy in the <span class="hlt">cross-correlation</span> analysis in the presence of MDS. At the group level, a large improvement in the results’ reliability with respect to single subject analysis was observed. The proposed Bayesian approach showed a slight improvement with respect to simple average results. Real data results were discussed in light of the simulated data tests and of the current physiological findings. PMID:27809243</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22968479','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22968479"><span>Muscle <span class="hlt">function</span> recovery in golden <span class="hlt">retriever</span> muscular dystrophy after AAV1-U7 exon skipping.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vulin, Adeline; Barthélémy, Inès; Goyenvalle, Aurélie; Thibaud, Jean-Laurent; Beley, Cyriaque; Griffith, Graziella; Benchaouir, Rachid; le Hir, Maëva; Unterfinger, Yves; Lorain, Stéphanie; Dreyfus, Patrick; Voit, Thomas; Carlier, Pierre; Blot, Stéphane; Garcia, Luis</p> <p>2012-11-01</p> <p>Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder resulting from lesions of the gene encoding dystrophin. These usually consist of large genomic deletions, the extents of which are not correlated with the severity of the phenotype. Out-of-frame deletions give rise to dystrophin deficiency and severe DMD phenotypes, while internal deletions that produce in-frame mRNAs encoding truncated proteins can lead to a milder myopathy known as Becker muscular dystrophy (BMD). Widespread restoration of dystrophin expression via adeno-associated virus (AAV)-mediated exon skipping has been successfully demonstrated in the mdx mouse model and in cardiac muscle after percutaneous transendocardial delivery in the golden <span class="hlt">retriever</span> muscular dystrophy dog (GRMD) model. Here, a set of optimized U7snRNAs carrying antisense sequences designed to rescue dystrophin were delivered into GRMD skeletal muscles by AAV1 gene transfer using intramuscular injection or forelimb perfusion. We show sustained correction of the dystrophic phenotype in extended muscle areas and partial recovery of muscle strength. Muscle architecture was improved and fibers displayed the hallmarks of mature and <span class="hlt">functional</span> units. A 5-year follow-up ruled out immune rejection drawbacks but showed a progressive decline in the number of corrected muscle fibers, likely due to the persistence of a mild dystrophic process such as occurs in BMD phenotypes. Although AAV-mediated exon skipping was shown safe and efficient to rescue a truncated dystrophin, it appears that recurrent treatments would be required to maintain therapeutic benefit ahead of the progression of the disease.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1812188E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1812188E"><span>Using the CARDAMOM framework to <span class="hlt">retrieve</span> global terrestrial ecosystem <span class="hlt">functioning</span> properties</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Exbrayat, Jean-François; Bloom, A. Anthony; Smallman, T. Luke; van der Velde, Ivar R.; Feng, Liang; Williams, Mathew</p> <p>2016-04-01</p> <p>Terrestrial ecosystems act as a sink for anthropogenic emissions of fossil-fuel and thereby partially offset the ongoing global warming. However, recent model benchmarking and intercomparison studies have highlighted the non-trivial uncertainties that exist in our understanding of key ecosystem properties like plant carbon allocation and residence times. It leads to worrisome differences in terrestrial carbon stocks simulated by Earth system models, and their evolution in a warming future. In this presentation we attempt to provide global insights on these properties by merging an ecosystem model with remotely-sensed global observations of leaf area and biomass through a data-assimilation system: the CARbon Data MOdel fraMework (CARDAMOM). CARDAMOM relies on a Markov Chain Monte Carlo algorithm to <span class="hlt">retrieve</span> confidence intervals of model parameters that regulate ecosystem properties independently of any prior land-cover information. The MCMC method thereby enables an explicit representation of the uncertainty in land-atmosphere fluxes and the evolution of terrestrial carbon stocks through time. Global experiments are performed for the first decade of the 21st century using a 1°×1° spatial resolution. Relationships emerge globally between key ecosystem properties. For example, our analyses indicate that leaf lifespan and leaf mass per area are highly correlated. Furthermore, there exists a latitudinal gradient in allocation patterns: high latitude ecosystems allocate more carbon to photosynthetic carbon (leaves) while plants invest more carbon in their structural parts (wood and root) in the wet tropics. Overall, the spatial distribution of these ecosystem properties does not correspond to usual land-cover maps and are also partially correlated with disturbance regimes. For example, fire-prone ecosystems present statistically significant higher values of carbon use efficiency than less disturbed ecosystems experiencing similar climatic conditions. These results</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120009492','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120009492"><span><span class="hlt">Retrieving</span> Aerosol in a Cloudy Environment: Aerosol Availability as a <span class="hlt">Function</span> of Spatial and Temporal Resolution</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Remer, Lorraine A.; Mattoo, Shana; Levy, Robert C.; Heidinger, Andrew; Pierce, R. Bradley; Chin, Mian</p> <p>2011-01-01</p> <p>The challenge of using satellite observations to <span class="hlt">retrieve</span> aerosol properties in a cloudy environment is to prevent contamination of the aerosol signal from clouds, while maintaining sufficient aerosol product yield to satisfy specific applications. We investigate aerosol <span class="hlt">retrieval</span> availability at different instrument pixel resolutions, using the standard MODIS aerosol cloud mask applied to MODIS data and a new GOES-R cloud mask applied to GOES data for a domain covering North America and surrounding oceans. Aerosol availability is not the same as the cloud free fraction and takes into account the technqiues used in the MODIS algorithm to avoid clouds, reduce noise and maintain sufficient numbers of aerosol <span class="hlt">retrievals</span>. The inherent spatial resolution of each instrument, 0.5x0.5 km for MODIS and 1x1 km for GOES, is systematically degraded to 1x1 km, 2x2 km, 4x4 km and 8x8 km resolutions and then analyzed as to how that degradation would affect the availability of an aerosol <span class="hlt">retrieval</span>, assuming an aerosol product resolution at 8x8 km. The results show that as pixel size increases, availability decreases until at 8x8 km 70% to 85% of the <span class="hlt">retrievals</span> available at 0.5 km have been lost. The diurnal pattern of aerosol <span class="hlt">retrieval</span> availability examined for one day in the summer suggests that coarse resolution sensors (i.e., 4x4 km or 8x8 km) may be able to <span class="hlt">retrieve</span> aerosol early in the morning that would otherwise be missed at the time of current polar orbiting satellites, but not the diurnal aerosol properties due to cloud cover developed during the day. In contrast finer resolution sensors (i.e., 1x1 km or 2x2 km) have much better opportunity to <span class="hlt">retrieve</span> aerosols in the partly cloudy scenes and better chance of returning the diurnal aerosol properties. Large differences in the results of the two cloud masks designed for MODIS aerosol and GOES cloud products strongly reinforce that cloud masks must be developed with specific purposes in mind and that a generic cloud mask</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.471.1565H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.471.1565H"><span><span class="hlt">Cross-correlating</span> Planck tSZ with RCSLenS weak lensing: implications for cosmology and AGN feedback</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hojjati, Alireza; Tröster, Tilman; Harnois-Déraps, Joachim; McCarthy, Ian G.; van Waerbeke, Ludovic; Choi, Ami; Erben, Thomas; Heymans, Catherine; Hildebrandt, Hendrik; Hinshaw, Gary; Ma, Yin-Zhe; Miller, Lance; Viola, Massimo; Tanimura, Hideki</p> <p>2017-10-01</p> <p>We present measurements of the spatial mapping between (hot) baryons and the total matter in the Universe, via the <span class="hlt">cross-correlation</span> between the thermal Sunyaev-Zeldovich (tSZ) map from Planck and the weak gravitational lensing maps from the Red Cluster Sequence Lensing Survey (RCSLenS). The <span class="hlt">cross-correlations</span> are performed on the map level where all the sources (including diffuse intergalactic gas) contribute to the signal. We consider two configuration-space correlation <span class="hlt">function</span> estimators, ξy-κ and ξ ^ {y-γ t}, and a Fourier-space estimator, C_{ℓ}^{y-κ}, in our analysis. We detect a significant correlation out to 3° of angular separation on the sky. Based on statistical noise only, we can report 13σ and 17σ detections of the <span class="hlt">cross-correlation</span> using the configuration-space y-κ and y-γt estimators, respectively. Including a heuristic estimate of the sampling variance yields a detection significance of 7σ and 8σ, respectively. A similar level of detection is obtained from the Fourier-space estimator, C_{ℓ}^{y-κ}. As each estimator probes different dynamical ranges, their combination improves the significance of the detection. We compare our measurements with predictions from the cosmo-OverWhelmingly Large Simulations suite of cosmological hydrodynamical simulations, where different galactic feedback models are implemented. We find that a model with considerable active galactic nuclei (AGN) feedback that removes large quantities of hot gas from galaxy groups and Wilkinson Microwave Anisotropy Probe 7-yr best-fitting cosmological parameters provides the best match to the measurements. All baryonic models in the context of a Planck cosmology overpredict the observed signal. Similar cosmological conclusions are drawn when we employ a halo model with the observed 'universal' pressure profile.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.463.3737C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.463.3737C"><span>CFHTLenS and RCSLenS: testing photometric redshift distributions using angular <span class="hlt">cross-correlations</span> with spectroscopic galaxy surveys</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Choi, A.; Heymans, C.; Blake, C.; Hildebrandt, H.; Duncan, C. A. J.; Erben, T.; Nakajima, R.; Van Waerbeke, L.; Viola, M.</p> <p>2016-12-01</p> <p>We determine the accuracy of galaxy redshift distributions as estimated from photometric redshift probability distributions p(z). Our method utilizes measurements of the angular <span class="hlt">cross-correlation</span> between photometric galaxies and an overlapping sample of galaxies with spectroscopic redshifts. We describe the redshift leakage from a galaxy photometric redshift bin j into a spectroscopic redshift bin i using the sum of the p(z) for the galaxies residing in bin j. We can then predict the angular <span class="hlt">cross-correlation</span> between photometric and spectroscopic galaxies due to intrinsic galaxy clustering when i ≠ j as a <span class="hlt">function</span> of the measured angular <span class="hlt">cross-correlation</span> when i = j. We also account for enhanced clustering arising from lensing magnification using a halo model. The comparison of this prediction with the measured signal provides a consistency check on the validity of using the summed p(z) to determine galaxy redshift distributions in cosmological analyses, as advocated by the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). We present an analysis of the photometric redshifts measured by CFHTLenS, which overlaps the Baryon Oscillation Spectroscopic Survey (BOSS). We also analyse the Red-sequence Cluster Lensing Survey, which overlaps both BOSS and the WiggleZ Dark Energy Survey. We find that the summed p(z) from both surveys are generally biased with respect to the true underlying distributions. If unaccounted for, this bias would lead to errors in cosmological parameter estimation from CFHTLenS by less than ˜4 per cent. For photometric redshift bins which spatially overlap in 3D with our spectroscopic sample, we determine redshift bias corrections which can be used in future cosmological analyses that rely on accurate galaxy redshift distributions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22689325','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22689325"><span>rTMS stimulation on left DLPFC affects emotional cue <span class="hlt">retrieval</span> as a <span class="hlt">function</span> of anxiety level and gender.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Balconi, Michela; Ferrari, Chiara</p> <p>2012-11-01</p> <p>Anxiety behaviour showed a consistent attentional bias toward negative and aversive memories, induced by a right dorsolateral prefrontal cortex (DLPFC) hyperactivation. In the present research, we explored the possible effect of rTMS (repeated transcranial magnetic stimulation) on the left DLPFC in memory <span class="hlt">retrieval</span> of positive versus negative emotional words, to induce a balanced response between the two hemispheres. Moreover, the gender effect in emotional memory processing was verified as a <span class="hlt">function</span> of the stimulus valence. Thirty subjects, who were divided in two different groups depending on their anxiety level (high/low anxiety, State-Trait-Anxiety Inventory (STAI)), were required to perform a task consisting of two experimental phases: an encoding phase (lists composed by positive and negative emotional words); and a <span class="hlt">retrieval</span> phase (old stimuli and new stimuli to be recognized). We found that the rTMS stimulation over left DLPFC affects the memory <span class="hlt">retrieval</span>. Specifically, high-anxiety subjects benefitted in greater measure to the frontal left stimulation with a reduced negative bias (increased accuracy and reduced response time (RT) for the positive stimuli). Whereas females showed a significant bias toward the negative memories, they did not benefit in greater measure to the TMS stimulation on the left hemisphere. These results suggested that left DLPFC activation favors the memory <span class="hlt">retrieval</span> of positive emotional information and may limit the "unbalance effect" induced by a right frontal hemispheric superiority in high levels of anxiety. © 2012 Wiley Periodicals, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15839797','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15839797"><span>Inverted-U <span class="hlt">function</span> between salivary cortisol and <span class="hlt">retrieval</span> of verbal memory after hydrocortisone treatment.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Domes, Gregor; Rothfischer, Julia; Reichwald, Ursula; Hautzinger, Martin</p> <p>2005-04-01</p> <p>The present study investigated the effect of a single oral dose of hydrocortisone (cortisol) on <span class="hlt">retrieval</span> of verbal and nonverbal declarative memory. Fifty-nine healthy participants were randomly assigned to either receive 25 mg cortisol or a placebo 45 min before <span class="hlt">retrieval</span> in a standardized memory test procedure. There was no global effect of cortisol on either verbal or nonverbal memory. However, a specific negative effect on free recall of associative verbal material appeared. In addition, high responders (salivary cortisol concentration>68.25 nmol/L) exhibited impaired verbal memory compared with low responders (<68.25 nmol/L). The results suggest specific nonlinear effects of cortisol on declarative memory <span class="hlt">retrieval</span>, which appear to be more pronounced for verbal material.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..456..288P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..456..288P"><span>Multifractal detrended <span class="hlt">cross-correlation</span> analysis of genome sequences using chaos-game representation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pal, Mayukha; Kiran, V. Satya; Rao, P. Madhusudana; Manimaran, P.</p> <p>2016-08-01</p> <p>We characterized the multifractal nature and power law <span class="hlt">cross-correlation</span> between any pair of genome sequence through an integrative approach combining 2D multifractal detrended <span class="hlt">cross-correlation</span> analysis and chaos game representation. In this paper, we have analyzed genomes of some prokaryotes and calculated fractal spectra h(q) and f(α) . From our analysis, we observed existence of multifractal nature and power law <span class="hlt">cross-correlation</span> behavior between any pair of genome sequences. Cluster analysis was performed on the calculated scaling exponents to identify the class affiliation and the same is represented as a dendrogram. We suggest this approach may find applications in next generation sequence analysis, big data analytics etc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..462..255Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..462..255Y"><span>Multifractal detrended <span class="hlt">cross-correlations</span> between crude oil market and Chinese ten sector stock markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Liansheng; Zhu, Yingming; Wang, Yudong; Wang, Yiqi</p> <p>2016-11-01</p> <p>Based on the daily price data of spot prices of West Texas Intermediate (WTI) crude oil and ten CSI300 sector indices in China, we apply multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA) method to investigate the <span class="hlt">cross-correlations</span> between crude oil and Chinese sector stock markets. We find that the strength of multifractality between WTI crude oil and energy sector stock market is the highest, followed by the strength of multifractality between WTI crude oil and financial sector market, which reflects a close connection between energy and financial market. Then we do vector autoregression (VAR) analysis to capture the interdependencies among the multiple time series. By comparing the strength of multifractality for original data and residual errors of VAR model, we get a conclusion that vector auto-regression (VAR) model could not be used to describe the dynamics of the <span class="hlt">cross-correlations</span> between WTI crude oil and the ten sector stock markets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IJBC...2630004N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IJBC...2630004N"><span>Nonlinear Analysis on <span class="hlt">Cross-Correlation</span> of Financial Time Series by Continuum Percolation System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Niu, Hongli; Wang, Jun</p> <p></p> <p>We establish a financial price process by continuum percolation system, in which we attribute price fluctuations to the investors’ attitudes towards the financial market, and consider the clusters in continuum percolation as the investors share the same investment opinion. We investigate the <span class="hlt">cross-correlations</span> in two return time series, and analyze the multifractal behaviors in this relationship. Further, we study the corresponding behaviors for the real stock indexes of SSE and HSI as well as the liquid stocks pair of SPD and PAB by comparison. To quantify the multifractality in <span class="hlt">cross-correlation</span> relationship, we employ multifractal detrended <span class="hlt">cross-correlation</span> analysis method to perform an empirical research for the simulation data and the real markets data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..467..326S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..467..326S"><span><span class="hlt">Cross-correlations</span> between the US monetary policy, US dollar index and crude oil market</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Xinxin; Lu, Xinsheng; Yue, Gongzheng; Li, Jianfeng</p> <p>2017-02-01</p> <p>This paper investigates the <span class="hlt">cross-correlations</span> between the US monetary policy, US dollar index and WTI crude oil market, using a dataset covering a period from February 4, 1994 to February 29, 2016. Our study contributes to the literature by examining the effect of the US monetary policy on US dollar index and WTI crude oil through the MF-DCCA approach. The empirical results show that the <span class="hlt">cross-correlations</span> between the three sets of time series exhibit strong multifractal features with the strength of multifractality increasing over the sample period. Employing a rolling window analysis, our empirical results show that the US monetary policy operations have clear influences on the <span class="hlt">cross-correlated</span> behavior of the three time series covered by this study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27795974','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27795974"><span>Versatile soft X-ray-optical <span class="hlt">cross-correlator</span> for ultrafast applications.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schick, Daniel; Eckert, Sebastian; Pontius, Niko; Mitzner, Rolf; Föhlisch, Alexander; Holldack, Karsten; Sorgenfrei, Florian</p> <p>2016-09-01</p> <p>We present an X-ray-optical <span class="hlt">cross-correlator</span> for the soft ([Formula: see text]) up to the hard X-ray regime based on a molybdenum-silicon superlattice. The <span class="hlt">cross-correlation</span> is done by probing intensity and position changes of superlattice Bragg peaks caused by photoexcitation of coherent phonons. This approach is applicable for a wide range of X-ray photon energies as well as for a broad range of excitation wavelengths and requires no external fields or changes of temperature. Moreover, the <span class="hlt">cross-correlator</span> can be employed on a 10 ps or 100 fs time scale featuring up to 50% total X-ray reflectivity and transient signal changes of more than 20%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..400...12M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..400...12M"><span>Autocorrelation and <span class="hlt">cross-correlation</span> in time series of homicide and attempted homicide</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Machado Filho, A.; da Silva, M. F.; Zebende, G. F.</p> <p>2014-04-01</p> <p>We propose in this paper to establish the relationship between homicides and attempted homicides by a non-stationary time-series analysis. This analysis will be carried out by Detrended Fluctuation Analysis (DFA), Detrended <span class="hlt">Cross-Correlation</span> Analysis (DCCA), and DCCA <span class="hlt">cross-correlation</span> coefficient, ρ(n). Through this analysis we can identify a positive <span class="hlt">cross-correlation</span> between homicides and attempted homicides. At the same time, looked at from the point of view of autocorrelation (DFA), this analysis can be more informative depending on time scale. For short scale (days), we cannot identify auto-correlations, on the scale of weeks DFA presents anti-persistent behavior, and for long time scales (n>90 days) DFA presents a persistent behavior. Finally, the application of this new type of statistical analysis proved to be efficient and, in this sense, this paper can contribute to a more accurate descriptive statistics of crime.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhyA..392.2915N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhyA..392.2915N"><span>One-factor model for the <span class="hlt">cross-correlation</span> matrix in the Vietnamese stock market</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nguyen, Quang</p> <p>2013-07-01</p> <p>Random matrix theory (RMT) has been applied to the analysis of the <span class="hlt">cross-correlation</span> matrix of a financial time series. The most important findings of previous studies using this method are that the eigenvalue spectrum largely follows that of random matrices but the largest eigenvalue is at least one order of magnitude higher than the maximum eigenvalue predicted by RMT. In this work, we investigate the <span class="hlt">cross-correlation</span> matrix in the Vietnamese stock market using RMT and find similar results to those of studies realized in developed markets (US, Europe, Japan) [9-18] as well as in other emerging markets[20,21,19,22]. Importantly, we found that the largest eigenvalue could be approximated by the product of the average <span class="hlt">cross-correlation</span> coefficient and the number of stocks studied. We demonstrate this dependence using a simple one-factor model. The model could be extended to describe other characteristics of the realistic data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5065566','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5065566"><span>Versatile soft X-ray-optical <span class="hlt">cross-correlator</span> for ultrafast applications</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Schick, Daniel; Eckert, Sebastian; Pontius, Niko; Mitzner, Rolf; Föhlisch, Alexander; Holldack, Karsten; Sorgenfrei, Florian</p> <p>2016-01-01</p> <p>We present an X-ray-optical <span class="hlt">cross-correlator</span> for the soft (>150 eV) up to the hard X-ray regime based on a molybdenum-silicon superlattice. The <span class="hlt">cross-correlation</span> is done by probing intensity and position changes of superlattice Bragg peaks caused by photoexcitation of coherent phonons. This approach is applicable for a wide range of X-ray photon energies as well as for a broad range of excitation wavelengths and requires no external fields or changes of temperature. Moreover, the <span class="hlt">cross-correlator</span> can be employed on a 10 ps or 100 fs time scale featuring up to 50% total X-ray reflectivity and transient signal changes of more than 20%. PMID:27795974</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JCAP...11..050B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JCAP...11..050B"><span>Needlet estimation of <span class="hlt">cross-correlation</span> between CMB lensing maps and LSS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bianchini, Federico; Renzi, Alessandro; Marinucci, Domenico</p> <p>2016-11-01</p> <p>In this paper we develop a novel needlet-based estimator to investigate the <span class="hlt">cross-correlation</span> between cosmic microwave background (CMB) lensing maps and large-scale structure (LSS) data. We compare this estimator with its harmonic counterpart and, in particular, we analyze the bias effects of different forms of masking. In order to address this bias, we also implement a MASTER-like technique in the needlet case. The resulting estimator turns out to have an extremely good signal-to-noise performance. Our analysis aims at expanding and optimizing the operating domains in CMB-LSS <span class="hlt">cross-correlation</span> studies, similarly to CMB needlet data analysis. It is motivated especially by next generation experiments (such as Euclid) which will allow us to derive much tighter constraints on cosmological and astrophysical parameters through <span class="hlt">cross-correlation</span> measurements between CMB and LSS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18345725','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18345725"><span>Small-scale seismic inversion using surface waves extracted from noise <span class="hlt">cross</span> <span class="hlt">correlation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gouédard, Pierre; Roux, Philippe; Campillo, Michel</p> <p>2008-03-01</p> <p>Green's <span class="hlt">functions</span> can be <span class="hlt">retrieved</span> between receivers from the correlation of ambient seismic noise or with an appropriate set of randomly distributed sources. This principle is demonstrated in small-scale geophysics using noise sources generated by human steps during a 10-min walk in the alignment of a 14-m-long accelerometer line array. The time-domain correlation of the records yields two surface wave modes extracted from the Green's <span class="hlt">function</span> between each pair of accelerometers. A frequency-wave-number Fourier analysis yields each mode contribution and their dispersion curve. These dispersion curves are then inverted to provide the one-dimensional shear velocity of the near surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930057659&hterms=dmr&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Ddmr','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930057659&hterms=dmr&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Ddmr"><span><span class="hlt">Cross-correlation</span> between the 170 GHz survey map and the COBE differential microwave radiometer first-year maps</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ganga, Ken; Cheng, ED; Meyer, Stephan; Page, Lyman</p> <p>1993-01-01</p> <p>This letter describes results of a <span class="hlt">cross-correlation</span> between the 170 GHz partial-sky survey, made with a 3.8 deg beam balloon-borne instrument, and the COBE DMR 'Fit Technique' reduced galaxy all-sky map with a beam of 7 deg. The strong correlation between the data sets implies that the observed structure is consistent with thermal variations in a 2.7 K emitter. A chi-square analysis applied to the correlation <span class="hlt">function</span> rules out the assumption that there is no structure in either of the two maps. A second test shows that if the DMR map has structure but the 170 GHz map does not, the probability of obtaining the observed correlation is small. Further analyses support the assumption that both maps have structure and that the 170 GHz-DMR <span class="hlt">cross-correlation</span> is consistent with the analogous DMR correlation <span class="hlt">function</span>. Maps containing various combinations of noise and Harrison-Zel'dovich power spectra are simulated and correlated to reinforce the result. The correlation provides compelling evidence that both instruments have observed fluctuations consistent with anisotropies in the cosmic microwave background.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930057659&hterms=cross+fit&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcross%2Bfit','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930057659&hterms=cross+fit&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcross%2Bfit"><span><span class="hlt">Cross-correlation</span> between the 170 GHz survey map and the COBE differential microwave radiometer first-year maps</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ganga, Ken; Cheng, ED; Meyer, Stephan; Page, Lyman</p> <p>1993-01-01</p> <p>This letter describes results of a <span class="hlt">cross-correlation</span> between the 170 GHz partial-sky survey, made with a 3.8 deg beam balloon-borne instrument, and the COBE DMR 'Fit Technique' reduced galaxy all-sky map with a beam of 7 deg. The strong correlation between the data sets implies that the observed structure is consistent with thermal variations in a 2.7 K emitter. A chi-square analysis applied to the correlation <span class="hlt">function</span> rules out the assumption that there is no structure in either of the two maps. A second test shows that if the DMR map has structure but the 170 GHz map does not, the probability of obtaining the observed correlation is small. Further analyses support the assumption that both maps have structure and that the 170 GHz-DMR <span class="hlt">cross-correlation</span> is consistent with the analogous DMR correlation <span class="hlt">function</span>. Maps containing various combinations of noise and Harrison-Zel'dovich power spectra are simulated and correlated to reinforce the result. The correlation provides compelling evidence that both instruments have observed fluctuations consistent with anisotropies in the cosmic microwave background.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvE..92e2815K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvE..92e2815K"><span>Detrended fluctuation analysis made flexible to detect range of <span class="hlt">cross-correlated</span> fluctuations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kwapień, Jarosław; Oświecimka, Paweł; DroŻdŻ, Stanisław</p> <p>2015-11-01</p> <p>The detrended <span class="hlt">cross-correlation</span> coefficient ρDCCA has recently been proposed to quantify the strength of <span class="hlt">cross-correlations</span> on different temporal scales in bivariate, nonstationary time series. It is based on the detrended <span class="hlt">cross-correlation</span> and detrended fluctuation analyses (DCCA and DFA, respectively) and can be viewed as an analog of the Pearson coefficient in the case of the fluctuation analysis. The coefficient ρDCCA works well in many practical situations but by construction its applicability is limited to detection of whether two signals are generally <span class="hlt">cross-correlated</span>, without the possibility to obtain information on the amplitude of fluctuations that are responsible for those <span class="hlt">cross-correlations</span>. In order to introduce some related flexibility, here we propose an extension of ρDCCA that exploits the multifractal versions of DFA and DCCA: multifractal detrended fluctuation analysis and multifractal detrended <span class="hlt">cross-correlation</span> analysis, respectively. The resulting new coefficient ρq not only is able to quantify the strength of correlations but also allows one to identify the range of detrended fluctuation amplitudes that are correlated in two signals under study. We show how the coefficient ρq works in practical situations by applying it to stochastic time series representing processes with long memory: autoregressive and multiplicative ones. Such processes are often used to model signals recorded from complex systems and complex physical phenomena like turbulence, so we are convinced that this new measure can successfully be applied in time-series analysis. In particular, we present an example of such application to highly complex empirical data from financial markets. The present formulation can straightforwardly be extended to multivariate data in terms of the q -dependent counterpart of the correlation matrices and then to the network representation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.3913K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.3913K"><span>Waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> at the International Data Centre: comparison with Reviewed Event Bulletin and regional catalogues</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kitov, Ivan; Bobrov, Dmitry; Rozhkov, Mikhail; Johansson, Peder</p> <p>2013-04-01</p> <p>Waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> substantially improves detection, phase association, and event building procedures at the International Data Centre (IDC) of the Comprehensive Nuclear-Test-Ban Treaty Organization. There were 50% to 100% events extra to the official Reviewed Event Bulletin (REB) were found in the aftershock sequences of small, middle size, and very big earthquakes. Several per cent of the events reported in the REB were not found with <span class="hlt">cross</span> <span class="hlt">correlation</span> even when all aftershocks were used as master events. These REB events are scrutinized in interactive analysis in order to reveal the reason of the <span class="hlt">cross</span> <span class="hlt">correlation</span> failure. As a corroborative method, we use detailed regional catalogues, which often include aftershocks with magnitudes between 2.0 and 3.0. Since the resolution of regional networks is by at least one unit of magnitude higher, the REB events missed from the relevant regional catalogues are considered as bogus. We compare events by origin time and location because the regional networks and the International Monitoring System are based on different sets of seismic stations and phase comparison is not possible. Three intracontinental sequences have been studied: after the March 20, 2008 earthquake in China (mb(IDC)=5.4), the May 20, 2012 event in Italy (mb(IDC)=5.3), and one earthquake (mb(IDC)=5.6) in Virginia, USA (August 23, 2011). Overall, most of the events not found by <span class="hlt">cross</span> <span class="hlt">correlation</span> are missing from the relevant regional catalogues. At the same time, these catalogues confirm most of additional REB events found only by <span class="hlt">cross</span> <span class="hlt">correlation</span>. This observation supports all previous findings of the improved quality of events built by <span class="hlt">cross</span> <span class="hlt">correlation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..93r4201S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..93r4201S"><span>Influence of <span class="hlt">cross</span> <span class="hlt">correlations</span> on interdiffusion in Al-rich Al-Ni melts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sondermann, Elke; Kargl, Florian; Meyer, Andreas</p> <p>2016-05-01</p> <p>The relation of self- and interdiffusion in a liquid metal, particularly the influence of <span class="hlt">cross</span> <span class="hlt">correlations</span> at low concentrations, is studied experimentally. Accurate interdiffusion data are obtained by a combination of x-ray radiography with the shear-cell method on the ground and on the sounding rocket MAPHEUS under microgravity conditions. Self-diffusion coefficients, measured by quasielastic neutron scattering, increase with decreasing Ni concentration, whereas interdiffusion coefficients are about constant. We show that <span class="hlt">cross</span> <span class="hlt">correlations</span> influence interdiffusion even at concentrations as low as 2 at. % Ni. Consequently, Darken's equation is not valid in this case.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/936750','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/936750"><span>High-Dynamic-Range Single-Shot <span class="hlt">Cross-Correlator</span> Based on an Optical Pulse Replicator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dorrer, C.; Bromage, J.; Zuegel, J.D.</p> <p>2008-09-05</p> <p>The operation of a single-shot <span class="hlt">cross-correlator</span> based on a pulse replicator is described. The correlator uses a discrete sequence of sampling pulses that are nonlinearly mixed with the pulse under test. The combination of a high reflector and partial reflector replicates an optical pulse by multiple internal reflections and generates a sequence of spatially displaced and temporally delayed sampling pulses. This principle is used in a <span class="hlt">cross-correlator</span> characterizing optical pulses at 1053 nm. A dynamic range higher than 60 dB is obtained over a temporal range larger than 200 ps.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013IAUS..290..249L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013IAUS..290..249L"><span><span class="hlt">Cross-correlation</span> of X-rays for 4U 1608-52</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lei, Y. J.; Zhang, H. T.; Luo, A. L.; Zhao, Y. H.</p> <p>2013-02-01</p> <p>We study the <span class="hlt">cross-correlation</span> between X-rays of different energies for the atoll-type source 4U 1608-52 with RXTE, and find the <span class="hlt">cross-correlation</span> evolutes along the different branches. The anti-correlation is reported from the Galactic black hole candidates and Z-type luminous sources in their hard states. Our results are a little different from the Z-type sources. Here we provide the first evidence that a similar anti-correlated feature can also be found in atoll-type source, and it is not corresponding to the lowest accretion rate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.S43G2555G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.S43G2555G"><span>Seismicity of the North Atlantic as measured by the International Data Centre using waveform <span class="hlt">cross</span> <span class="hlt">correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Given, J. W.; Bobrov, D.; Kitov, I. O.; Spiliopoulos, S.</p> <p>2012-12-01</p> <p>The Technical Secretariat (TS) of the Comprehensive Nuclear Test-Ban Treaty Organization (CTBTO) will carry out the verification of the CTBT which obligates each State Party not to carry out any nuclear explosions, independently of their size and purpose. The International Data Centre (IDC) receives, collects, processes, analyses, reports on and archives data from the International Monitoring System(IMS). The IDC is responsible for automatic and interactive processing of the IMS data and for standard IDC products. The IDC is also required by the Treaty to progressively enhance its technical capabilities. In this study, we use waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> as a technique to improve the detection capability and reliability of the seismic part of the IMS. In order to quantitatively estimate the gain obtained by <span class="hlt">cross</span> <span class="hlt">correlation</span> on the current sensitivity of automatic and interactive processing we compared seismic bulletins built for the North Atlantic (NA), which is an isolated region with earthquakes concentrating around the Mid-Atlantic Ridge. This avoids the influence of adjacent seismic regions on the final bulletins: the Reviewed Event Bulletin (REB) issued by the International Data Centre and the <span class="hlt">cross</span> <span class="hlt">correlation</span> Standard Event List (XSEL). We have <span class="hlt">cross</span> <span class="hlt">correlated</span> waveforms from ~1500 events reported in the REB since 2009. The resulting <span class="hlt">cross</span> <span class="hlt">correlation</span> matrix revealed the best candidates for master events. High-quality signals (SNR>5.0) recorded at eighteen array stations from approximately 50 master events evenly distributed over the seismically active zone in the NA were selected as templates. These templates are used for a continuous calculation of <span class="hlt">cross</span> <span class="hlt">correlation</span> coefficients since 2011. All detections obtained by <span class="hlt">cross-correlation</span> are then used to build events according to the current IDC definition, i.e. at least three primary stations with accurate arrival times, azimuth and slowness estimates. The qualified event hypotheses populated the XSEL. In</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.3920K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.3920K"><span>Seismicity of the North Atlantic as measured by the International Data Centre using waveform <span class="hlt">cross</span> <span class="hlt">correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kitov, Ivan; Bobrov, Dmitry; Rozhkov, Mikhail</p> <p>2013-04-01</p> <p>The Technical Secretariat (TS) of the Comprehensive Nuclear Test-Ban Treaty Organization (CTBTO) will carry out the verification of the CTBT which obligates each State Party not to carry out nuclear explosions. The International Data Centre (IDC) receives, collects, processes, analyses, reports on and archives data from the International Monitoring System. The IDC is responsible for automatic and interactive processing of the International Monitoring System (IMS) data and for standard IDC products. The IDC is also required by the Treaty to progressively enhance its technical capabilities. In this study, we use waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> as a technique to improve the detection capability and reliability of the seismic part of the IMS. In order to quantitatively estimate the gain obtained by <span class="hlt">cross</span> <span class="hlt">correlation</span> on the current sensitivity of automatic and interactive processing we compared seismic bulletins built for the North Atlantic (NA), which is a seismically isolated region with earthquakes concentrating around the Mid-Atlantic Ridge. This allows avoiding the spill-over of mislocated events between adjacent seismic regions and biases in the final bulletins: the Reviewed Event Bulletin (REB) issued by the IDC and the <span class="hlt">cross</span> <span class="hlt">correlation</span> Standard Event List (XSEL). To begin with, we <span class="hlt">cross</span> <span class="hlt">correlated</span> waveforms recorded at 18 IMS array stations from ~1500 events reported in the REB between 2009 and 2011. The resulting <span class="hlt">cross</span> <span class="hlt">correlation</span> matrix revealed the best candidates for master events. We have selected 60 master events evenly distributed over the seismically active zone in the NA. High-quality signals (SNR>5.0) recorded by 10 most sensitive array stations were used as waveform templates. These templates are used for a continuous calculation of <span class="hlt">cross</span> <span class="hlt">correlation</span> coefficients in the first half of 2012. All detections obtained by <span class="hlt">cross-correlation</span> are then used to build events according to the current IDC definition: at least three primary stations with accurate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730037253&hterms=kawasaki&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dkawasaki','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730037253&hterms=kawasaki&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dkawasaki"><span><span class="hlt">Cross-correlation</span> analysis of the AE index and the interplanetary magnetic field Bz component.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Meng, C.-I.; Tsurutani, B.; Kawasaki, K.; Akasofu, S.-I.</p> <p>1973-01-01</p> <p>A <span class="hlt">cross-correlation</span> study between magnetospheric activity (the AE index) and the southward-directed component of the interplanetary magnetic field (IMF) is made for a total of 792 hours (33 days) with a time resolution of about 5.5 min. The peak correlation tends to occur when the interplanetary data are shifted approximately 40 min later with respect to the AE index data. <span class="hlt">Cross-correlation</span> analysis is conducted on some idealized wave forms to illustrate that this delay between southward turning of the IMF and the AE index should not be interpreted as being the duration of the growth phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730037253&hterms=BZ&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DBZ','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730037253&hterms=BZ&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DBZ"><span><span class="hlt">Cross-correlation</span> analysis of the AE index and the interplanetary magnetic field Bz component.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Meng, C.-I.; Tsurutani, B.; Kawasaki, K.; Akasofu, S.-I.</p> <p>1973-01-01</p> <p>A <span class="hlt">cross-correlation</span> study between magnetospheric activity (the AE index) and the southward-directed component of the interplanetary magnetic field (IMF) is made for a total of 792 hours (33 days) with a time resolution of about 5.5 min. The peak correlation tends to occur when the interplanetary data are shifted approximately 40 min later with respect to the AE index data. <span class="hlt">Cross-correlation</span> analysis is conducted on some idealized wave forms to illustrate that this delay between southward turning of the IMF and the AE index should not be interpreted as being the duration of the growth phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhyA..390..837L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhyA..390..837L"><span><span class="hlt">Cross-correlations</span> in volume space: Differences between buy and sell volumes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Sun Young; Hwang, Dong Il; Kim, Min Jae; Koh, In Gyu; Kim, Soo Yong</p> <p>2011-03-01</p> <p>We study the <span class="hlt">cross-correlations</span> of buy and sell volumes on the Korean stock market in high frequency. We observe that the pulling effects of volumes are as small as that of returns. The properties of the correlations of buy and sell volumes differ. They are explained by the degree of synchronization of stock volumes. Further, the pulling effects on the minimal spanning tree are studied. In minimal spanning trees with directed links, the large pulling effects are clustered at the center, not uniformly distributed. The Epps effect of buy and sell volumes are observed. The reversal of the <span class="hlt">cross-correlations</span> of buy and sell volumes is also detected.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3864110','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3864110"><span>Event-Related <span class="hlt">Functional</span> Magnetic Resonance Imaging Changes during Relational <span class="hlt">Retrieval</span> in Normal Aging and Amnestic Mild Cognitive Impairment</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Giovanello, Kelly S.; De Brigard, Felipe; Ford, Jaclyn Hennessey; Kaufer, Daniel I.; Burke, James R.; Browndyke, Jeffrey N.; Welsh-Bohmer, Kathleen A.</p> <p>2013-01-01</p> <p>The earliest cognitive deficits observed in amnestic mild cognitive impairment (aMCI) appear to center on memory tasks that require relational memory (RM), the ability to link or integrate unrelated pieces of information. RM impairments in aMCI likely reflect neural changes in the medial temporal lobe (MTL) and posterior parietal cortex (PPC). We tested the hypothesis that individuals with aMCI, as compared to cognitively normal (CN) controls, would recruit neural regions outside of the MTL and PPC to support relational memory. To this end, we directly compared the neural underpinnings of successful relational <span class="hlt">retrieval</span> in aMCI and CN groups, using event-related <span class="hlt">functional</span> magnetic resonance imaging (fMRI), holding constant the stimuli and encoding task. The fMRI data showed that the CN, compared to the aMCI, group activated left precuneus, left angular gyrus, right posterior cingulate, and right parahippocampal cortex during relational <span class="hlt">retrieval</span>, while the aMCI group, relative to the CN group, activated superior temporal gyrus and supramarginal gyrus for this comparison. Such findings indicate an early shift in the <span class="hlt">functional</span> neural architecture of relational <span class="hlt">retrieval</span> in aMCI, and may prove useful in future studies aimed at capitalizing on <span class="hlt">functionally</span> intact neural regions as targets for treatment and slowing of the disease course. PMID:22622022</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17055702','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17055702"><span>Modeling of context-dependent <span class="hlt">retrieval</span> in hippocampal region CA1: implications for cognitive <span class="hlt">function</span> in schizophrenia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Siekmeier, Peter J; Hasselmo, Michael E; Howard, Marc W; Coyle, Joseph</p> <p>2007-01-01</p> <p>The symptoms of schizophrenia may be associated with reductions in NMDA receptor (NMDAR) <span class="hlt">function</span>. This is suggested by the psychotomimetic effects of NMDA antagonists, the ameliorative effects of NMDAR indirect agonists, elevated levels of the NMDA antagonist N-acetyl-aspartyl-glutamate (NAAG) in schizophrenic brain, and findings from recent genetic studies. However, the link between reduced NMDAR <span class="hlt">function</span> and the behavioral features of schizophrenics has not been made explicit. Here we present a network simulation of hippocampal <span class="hlt">function</span>, focused on <span class="hlt">retrieval</span> of verbal stimuli in human memory tasks. Specifically, we trained a computational model of the hippocampal complex to perform a context-dependent paired associate task, a free recall task with category clustering, and the transitive inference (TI) task. In this network, direct perforant pathway input from entorhinal cortex to region CA1 provides the basis for semantic context cueing during initial encoding and <span class="hlt">retrieval</span>, allowing selective <span class="hlt">retrieval</span> on the basis of category cues. Alterations in the magnitude of this direct perforant pathway input to region CA1 causes impairments in use of organizational strategies for memory, accounting for specific features of memory dysfunction in schizophrenics and in normals treated with ketamine. This model provides a theoretical link between cellular physiological changes and specific cognitive symptoms. As such, it can shed light on the etiology of schizophrenia in a fundamental way, and also holds the promise of pointing the way to more effective treatments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S43B2529O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S43B2529O"><span>Ambient seismic noise <span class="hlt">cross-correlations</span> in an active underground mine</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Olivier, G.; Brenguier, F.; Campillo, M.</p> <p>2013-12-01</p> <p>Over the past few years <span class="hlt">cross-correlating</span> ambient seismic noise for imaging and monitoring purposes has been used, almost exclusively, in crustal studies. In this case the noise is dominated by surface waves emanating from the interaction of the ocean with the solid earth. The strength of these surface waves decreases rapidly with depth, so in an underground mining environment the noise is instead dominated by human activity associated with mining - guided surface waves along tunnels and direct body waves traveling through the host rock. The location and origin of the noise sources vary in time, while additionally the state and material properties of the medium change on a daily basis due to active mining. These conditions give ideal opportunities to examine the influences of noise source and medium changes on the stability of <span class="hlt">cross-correlation</span> <span class="hlt">functions</span> (CCFs) respectively. We present the results of 5 months of data recorded in an active underground mine roughly 1km below surface. The standard mine seismic array, consisting of 18 high-frequency geophones (7 tri-axial and 11 uni-axial), was used to record continuous data at a sampling rate of 6000 Hz. This amounts to roughly 10 TB of seismic data. CCFs are computed every three minutes in different frequency bands between 20 and 2000 Hz for all 482 station pairs. The stability of the CCFs are examined for the different frequency bands and the changes are isolated in terms of changes in noise sources or changes in the medium. In the mine selected for this project, tunnels and excavations are regularly surveyed. Since the locations of these strong scatterers are known to a good accuracy, we can apply finite difference numerical modeling to examine seismic wave propagation in this heterogeneous medium. The results of a 3 km^3 numerical model with realistic tunnels and excavations are shown. Synthetic Green's <span class="hlt">functions</span> are generated between all station pairs and compared with the CCFs calculated with real seismic data</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=memory+AND+fMRI&pg=3&id=EJ776756','ERIC'); return false;" href="http://eric.ed.gov/?q=memory+AND+fMRI&pg=3&id=EJ776756"><span>Spatial and Temporal Episodic Memory <span class="hlt">Retrieval</span> Recruit Dissociable <span class="hlt">Functional</span> Networks in the Human Brain</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ekstrom, Arne D.; Bookheimer, Susan Y.</p> <p>2007-01-01</p> <p>Imaging, electrophysiological studies, and lesion work have shown that the medial temporal lobe (MTL) is important for episodic memory; however, it is unclear whether different MTL regions support the spatial, temporal, and item elements of episodic memory. In this study we used fMRI to examine <span class="hlt">retrieval</span> performance emphasizing different aspects…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=memory+AND+fMRI&pg=3&id=EJ776756','ERIC'); return false;" href="https://eric.ed.gov/?q=memory+AND+fMRI&pg=3&id=EJ776756"><span>Spatial and Temporal Episodic Memory <span class="hlt">Retrieval</span> Recruit Dissociable <span class="hlt">Functional</span> Networks in the Human Brain</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ekstrom, Arne D.; Bookheimer, Susan Y.</p> <p>2007-01-01</p> <p>Imaging, electrophysiological studies, and lesion work have shown that the medial temporal lobe (MTL) is important for episodic memory; however, it is unclear whether different MTL regions support the spatial, temporal, and item elements of episodic memory. In this study we used fMRI to examine <span class="hlt">retrieval</span> performance emphasizing different aspects…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA325404','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA325404"><span>Combined Radar-Radiometer Rainfall <span class="hlt">Retrieval</span> for TRMM Using Structure <span class="hlt">Function</span>-Based Optimization</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2011-07-28</p> <p>Cumulonimbus vertical velocity events in GATE. Part II: Synthesis and model core structure. J. Appi . Meteor., 37, 2458-2469. 187 BIOGRAPHICAL SKETCH...rainfall <span class="hlt">retrieval</span> algorithms,. J. Appi . Meteor., 33, 313-333. Farrar, M.R., and E.A. Smith, 1992: Spatial resolution enhancement of terrestrial features</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/9597658','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/9597658"><span><span class="hlt">Functional</span>-anatomic study of episodic <span class="hlt">retrieval</span>. II. Selective averaging of event-related fMRI trials to test the <span class="hlt">retrieval</span> success hypothesis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Buckner, R L; Koutstaal, W; Schacter, D L; Dale, A M; Rotte, M; Rosen, B R</p> <p>1998-04-01</p> <p>In a companion paper (R. L. Buckner et al., 1998, NeuroImage 7, 151-162) we used fMRI to identify brain areas activated by episodic memory <span class="hlt">retrieval</span>. Prefrontal areas were shown to differentiate component processes related to <span class="hlt">retrieval</span> success and <span class="hlt">retrieval</span> effort in block-designed paradigms. Importantly, a right anterior prefrontal area was most active during task blocks involving greatest <span class="hlt">retrieval</span> success, consistent with an earlier PET study by M. D. Rugg et al. (1996, Brain 119, 2073-2083). However, manipulation of these variables within the context of blocked trials confounds differences related to varying levels of <span class="hlt">retrieval</span> success with potential shifts in subjects' strategies due to changes in the probability of target events across blocks. To test more rigorously the hypothesis that certain areas are directly related to <span class="hlt">retrieval</span> success, we adopted recently developed procedures for event-related fMRI. Fourteen subjects studied words under deep encoding and were then tested in a mixed trial paradigm where old and new words were randomly presented. This recognition testing procedure activated similar areas to the blocked trial paradigm, with all areas showing similar levels of activation across old and new items. Of critical importance, significant activation was detected in right anterior prefrontal cortex for new items when subjects correctly indicated they were new (correct rejections). These findings go against the <span class="hlt">retrieval</span> success hypothesis as formally proposed and provide an important constraint for interpretation of this region's role in episodic <span class="hlt">retrieval</span>. Furthermore, anterior prefrontal activation was found to occur late, relative to other brain areas, suggesting that it may be involved in <span class="hlt">retrieval</span> verification or monitoring processes or perhaps even in anticipation of subsequent trial events (although an alternative possibility, that the late onset is mediated by a late vascular response, cannot be ruled out). These findings and their</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25337381','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25337381"><span>Evaluation of Phase Locking and <span class="hlt">Cross</span> <span class="hlt">Correlation</span> Methods for Estimating the Time Lag between Brain Sites: A Simulation Approach.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Soltanzadeh, Mohammad Javad; Daliri, Mohammad Reza</p> <p>2014-01-01</p> <p>Direction and latency of electrical connectivity between different sites of brain explains brain neural <span class="hlt">functionality</span>. We compared efficiency of <span class="hlt">cross</span> <span class="hlt">correlation</span> and phase locking methods in time lag estimation which are based on local field potential (LFP) and LFP-spike signals, respectively. Signals recorded from MT area of a macaque's brain was used in a simulation approach. The first signal was real brain activity and the second was identical to the first one, but with two kinds of delayed and not delayed forms. Time lag between two signals was estimated by <span class="hlt">cross</span> <span class="hlt">correlation</span> and phase locking methods. Both methods estimated the time lags with no errors. Phase locking was not as time efficient as correlation. In addition, phase locking suffered from temporal self bias. Correlation was a more efficient method. Phase locking was not considered as a proper method to estimate the time lags between brain sites due to time inefficiency and self bias, the problems which are reported for the first time about this method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AAS...21725509M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AAS...21725509M"><span>Angular <span class="hlt">Cross-correlation</span> of Spitzer IRAC and Herschel Spire Sources</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mitchell-Wynne, Ketron; Cooray, A.; Wang, L.; HerMES Consortium</p> <p>2011-01-01</p> <p>The Spitzer Deep Wide-Field Survey (SDWFS) and the Herschel Multi-tiered Extragalactic Survey (HerMES) each provide deep and wide coverage, centered on the Bootes field, at infrared and sub-millimeter wavelengths. The SDWFS covers approximately 8.5 square degrees with sensitivities of galaxies out to z 3. From the public SDWFS source catalog, we remove stars and contaminants by concentration, using selection methods based on IRAC and optical colors; optical photometry is provided by the NOAO Deep Wide-Field Survey. Photometric redshifts of detected IRAC sources are then determined using the 1.6 micron spectral feature (or 'bump'). We classify three different kinds of bumps, (bump 1- bump 3), with redshifts ranging approximately from 0-1.3, 1.3-2, and 2-3 respectively. The number of bump 1 sources in the SDWFS catalogs were found to be in excess of 25,000 at the 5 sigma detection limit of the 3.6 micron channel of the IRAC instrument. Bump 2 and bump 3 source identification yielded similar, but slightly fewer counts. We also extract a separate catalog of 2500 or so dust-obscured galaxies (DOGs) at z 2 using 24 micron and r-band fluxes. As part of HerMES observations with SPIRE, the Bootes field contain more than 15,000 clearly detected SPIRE sources at 250 microns, In this paper we report on the <span class="hlt">cross</span> <span class="hlt">correlation</span> <span class="hlt">function</span> of these bump sources with the source catalogs from three bands of the SPIRE instrument onboard Herschel. The aim is to broadly reconstruct the redshift distribution of SPIRE sources using redshift distributions of bump and DOGs in the bootes field and the relative clustering strengths.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..462..442C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..462..442C"><span><span class="hlt">Cross-correlation</span> patterns in social opinion formation with sequential data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chakrabarti, Anindya S.</p> <p>2016-11-01</p> <p>Recent research on large-scale internet data suggests existence of patterns in the collective behavior of billions of people even though each of them may pursue own activities. In this paper, we interpret online rating activity as a process of forming social opinion about individual items, where people sequentially choose a rating based on the current information set comprising all previous ratings and own preferences. We construct an opinion index from the sequence of ratings and we show that (1) movie-specific opinion converges much slower than an independent and identically distributed (i.i.d.) sequence of ratings, (2) rating sequence for individual movies shows lesser variation compared to an i.i.d. sequence of ratings, (3) the probability density <span class="hlt">function</span> of the asymptotic opinions has more spread than that defined over opinion arising from i.i.d. sequence of ratings, (4) opinion sequences across movies are correlated with significantly higher and lower correlation compared to opinion constructed from i.i.d. sequence of ratings, creating a bimodal <span class="hlt">cross-correlation</span> structure. By decomposing the temporal correlation structures from panel data of movie ratings, we show that the social effects are very prominent whereas group effects cannot be differentiated from those of surrogate data and individual effects are quite small. The former explains a large part of extreme positive or negative correlations between sequences of opinions. In general, this method can be applied to any rating data to extract social or group-specific effects in correlation structures. We conclude that in this particular case, social effects are important in opinion formation process.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22047125','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22047125"><span><span class="hlt">Cross-correlation</span> based time delay estimation for turbulent flow velocity measurements: Statistical considerations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tal, Balazs; Bencze, Attila; Zoletnik, Sandor; Veres, Gabor; Por, Gabor</p> <p>2011-12-15</p> <p>Time delay estimation methods (TDE) are well-known techniques to investigate poloidal flows in hot magnetized plasmas through the propagation properties of turbulent structures in the medium. One of these methods is based on the estimation of the time lag at which the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> (CCF) estimation reaches its maximum value. The uncertainty of the peak location refers to the smallest determinable flow velocity modulation, and therefore the standard deviation of the time delay imposes important limitation to the measurements. In this article, the relative standard deviation of the CCF estimation and the standard deviation of its peak location are calculated analytically using a simple model of turbulent signals. This model assumes independent (non interacting) overlapping events (coherent structures) with randomly distributed spatio-temporal origins moving with background flow. The result of our calculations is the derivation of a general formula for the CCF variance, which is valid not exclusively in the high event density limit, but also for arbitrary event densities. Our formula reproduces the well known expression for high event densities previously published in the literature. In this paper we also present a derivation of the variance of time delay estimation that turns out to be inversely proportional to the applied time window. The derived formulas were tested in real plasma measurements. The calculations are an extension of the earlier work of Bencze and Zoletnik [Phys. Plasmas 12, 052323 (2005)] where the autocorrelation-width technique was developed. Additionally, we show that velocities calculated by a TDE method possess a broadband noise which originates from this variance, its power spectral density cannot be decreased by worsening the time resolution and can be coherent with noises of other velocity measurements where the same turbulent structures are used. This noise should not be confused with the impact of zero mean frequency zonal flow</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MsT.........13S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MsT.........13S"><span><span class="hlt">Cross</span> <span class="hlt">correlation</span> calculations and neutron scattering analysis for a portable solid state neutron detection system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saltos, Andrea</p> <p></p> <p>In efforts to perform accurate dosimetry, Oakes et al. [Nucl. Intrum. Mehods. (2013)] introduced a new portable solid state neutron rem meter based on an adaptation of the Bonner sphere and the position sensitive long counter. The system utilizes high thermal efficiency neutron detectors to generate a linear combination of measurement signals that are used to estimate the incident neutron spectra. The inversion problem associated to deduce dose from the counts in individual detector elements is addressed by applying a <span class="hlt">cross-correlation</span> method which allows estimation of dose with average errors less than 15%. In this work, an evaluation of the performance of this system was extended to take into account new correlation techniques and neutron scattering contribution. To test the effectiveness of correlations, the Distance correlation, Pearson Product-Moment correlation, and their weighted versions were performed between measured spatial detector responses obtained from nine different test spectra, and the spatial response of Library <span class="hlt">functions</span> generated by MCNPX. Results indicate that there is no advantage of using the Distance Correlation over the Pearson Correlation, and that weighted versions of these correlations do not increase their performance in evaluating dose. Both correlations were proven to work well even at low integrated doses measured for short periods of time. To evaluate the contribution produced by room-return neutrons on the dosimeter response, MCNPX was used to simulate dosimeter responses for five isotropic neutron sources placed inside different sizes of rectangular concrete rooms. Results show that the contribution of scattered neutrons to the response of the dosimeter can be significant, so that for most cases the dose is over predicted with errors as large as 500%. A possible method to correct for the contribution of room-return neutrons is also assessed and can be used as a good initial estimate on how to approach the problem.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26952461','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26952461"><span><span class="hlt">Cross-correlative</span> 3D micro-structural investigation of human bone processed into bone allografts.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Singh, Atul Kumar; Gajiwala, Astrid Lobo; Rai, Ratan Kumar; Khan, Mohd Parvez; Singh, Chandan; Barbhuyan, Tarun; Vijayalakshmi, S; Chattopadhyay, Naibedya; Sinha, Neeraj; Kumar, Ashutosh; Bellare, Jayesh R</p> <p>2016-05-01</p> <p>Bone allografts (BA) are a cost-effective and sustainable alternative in orthopedic practice as they provide a permanent solution for preserving skeletal architecture and <span class="hlt">function</span>. Such BA however, must be processed to be disease free and immunologically safe as well as biologically and clinically useful. Here, we have demonstrated a processing protocol for bone allografts and investigated the micro-structural properties of bone collected from osteoporotic and normal human donor samples. In order to characterize BA at different microscopic levels, a combination of techniques such as Solid State Nuclear Magnetic Resonance (ssNMR), Scanning Electron Microscope (SEM), micro-computed tomography (μCT) and Thermal Gravimetric Analysis (TGA) were used for delineating the ultra-structural property of bone. ssNMR revealed the extent of water, collagen fine structure and crystalline order in the bone. These were greatly perturbed in the bone taken from osteoporotic bone donor. Among the processing methods analyzed, pasteurization at 60 °C and radiation treatment appeared to substantially alter the bone integrity. SEM study showed a reduction in Ca/P ratio and non-uniform distribution of elements in osteoporotic bones. μ-CT and MIMICS (Materialize Interactive Medical Image Control System) demonstrated that pasteurization and radiation treatment affects the BA morphology and cause a shift in the HU unit. However, the combination of all these processes restored all-important parameters that are critical for BA integrity and sustainability. <span class="hlt">Cross-correlation</span> between the various probes we used quantitatively demonstrated differences in morphological and micro-structural properties between BA taken from normal and osteoporotic human donor. Such details could also be instrumental in designing an appropriate bone scaffold. For the best restoration of bone microstructure and to be used as a biomaterial allograft, a step-wise processing method is recommended that preserves all</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21371818','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21371818"><span><span class="hlt">CROSS-CORRELATION</span> WEAK LENSING OF SDSS GALAXY CLUSTERS. I. MEASUREMENTS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sheldon, Erin S.; Johnston, David E.; Scranton, Ryan; Koester, Benjamin P.; Oyaizu, Hiroaki; Cunha, Carlos; Lima, Marcos; Frieman, Joshua A.; McKay, Timothy A.; Lin Huan; Annis, James; Wechsler, Risa H.; Mandelbaum, Rachel; Bahcall, Neta A.; Fukugita, Masataka</p> <p>2009-10-01</p> <p>This is the first in a series of papers on the weak lensing effect caused by clusters of galaxies in Sloan Digital Sky Survey. The photometrically selected cluster sample, known as MaxBCG, includes approx130,000 objects between redshift 0.1 and 0.3, ranging in size from small groups to massive clusters. We split the clusters into bins of richness and luminosity and stack the surface density contrast to produce mean radial profiles. The mean profiles are detected over a range of scales, from the inner halo (25 kpc h {sup -1}) well into the surrounding large-scale structure (30 Mpc h {sup -1}), with a significance of 15 to 20 in each bin. The signal over this large range of scales is best interpreted in terms of the cluster-mass <span class="hlt">cross-correlation</span> <span class="hlt">function</span>. We pay careful attention to sources of systematic error, correcting for them where possible. The resulting signals are calibrated to the approx10% level, with the dominant remaining uncertainty being the redshift distribution of the background sources. We find that the profiles scale strongly with richness and luminosity. We find that the signal within a given richness bin depends upon luminosity, suggesting that luminosity is more closely correlated with mass than galaxy counts. We split the samples by redshift but detect no significant evolution. The profiles are not well described by power laws. In a subsequent series of papers, we invert the profiles to three-dimensional mass profiles, show that they are well fit by a halo model description, measure mass-to-light ratios, and provide a cosmological interpretation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/27171','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/27171"><span>Spatial <span class="hlt">cross-correlation</span> of undisturbed, natural shortleaf pine stands in northern Georgia</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Robin M. Reich; Raymond L. Czaplewski; William A. Bechtold</p> <p>1994-01-01</p> <p>In this study a <span class="hlt">cross-correlation</span> statistic is used to analyse the spatial relationship among stand characteristics of natural, undisturbed shortleaf pine stands sampled during 1961-72 and 1972-82 in northern Georgia. Stand characteristics included stand age, site index, tree density, hardwood competition, and mortality. In each time period, the spatial cross-...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..403...35S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..403...35S"><span>Multiscale multifractal detrended <span class="hlt">cross-correlation</span> analysis of financial time series</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shi, Wenbin; Shang, Pengjian; Wang, Jing; Lin, Aijing</p> <p>2014-06-01</p> <p>In this paper, we introduce a method called multiscale multifractal detrended <span class="hlt">cross-correlation</span> analysis (MM-DCCA). The method allows us to extend the description of the <span class="hlt">cross-correlation</span> properties between two time series. MM-DCCA may provide new ways of measuring the nonlinearity of two signals, and it helps to present much richer information than multifractal detrended <span class="hlt">cross-correlation</span> analysis (MF-DCCA) by sweeping all the range of scale at which the multifractal structures of complex system are discussed. Moreover, to illustrate the advantages of this approach we make use of the MM-DCCA to analyze the <span class="hlt">cross-correlation</span> properties between financial time series. We show that this new method can be adapted to investigate stock markets under investigation. It can provide a more faithful and more interpretable description of the dynamic mechanism between financial time series than traditional MF-DCCA. We also propose to reduce the scale ranges to analyze short time series, and some inherent properties which remain hidden when a wide range is used may exhibit perfectly in this way.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JAG...135...55A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JAG...135...55A"><span>Refinement of arrival-time picks using a <span class="hlt">cross-correlation</span> based workflow</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Akram, Jubran; Eaton, David W.</p> <p>2016-12-01</p> <p>We propose a new iterative workflow based on <span class="hlt">cross-correlation</span> for improved arrival-time picking on microseismic data. In this workflow, signal-to-noise ratio (S/N) and polarity weighted stacking are used to minimize the effect of S/N and polarity fluctuations on the pilot waveform computation. We use an exhaustive search technique for polarity estimation through stack power maximization. We use pseudo-synthetic and real microseismic data from western Canada in order to demonstrate the effectiveness of proposed workflow relative to Akaike information criterion (AIC) and a previously published <span class="hlt">cross-correlation</span> based method. The pseudo-synthetic microseismic waveforms are obtained by introducing Gaussian noise and polarity fluctuations into waveforms from a high S/N microseismic event. We find that the <span class="hlt">cross-correlation</span> based approaches yield more accurate arrival-time picks as compared to AIC for low S/N waveforms. AIC is not affected by waveform polarities as it works on individual receiver levels whereas the accuracy of existing <span class="hlt">cross-correlation</span> method decreases in spite of using envelope correlation. We show that our proposed workflow yields better and consistent arrival-time picks regardless of waveform amplitude and polarity variations within the receiver array. After refinement, the initial arrival-time picks are located closer to the best estimated manual picks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1246776','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1246776"><span><span class="hlt">Cross-correlation</span> analysis of the maintained discharge of rabbit retinal ganglion cells.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Arnett, D; Spraker, T E</p> <p>1981-01-01</p> <p>1. Simultaneous recordings were made from pairs of rabbit retinal ganglion cells. Physiological tests were used to classify the receptive field properties of each cell and the receptive field locations were mapped. 2. The statistical dependence between simultaneously recorded retinal ganglion cells was assessed by <span class="hlt">cross-correlating</span> the maintained discharge of the simultaneously recorded cells. <span class="hlt">Cross-correlations</span> from cell pairs in which the constituent cells had non-overlapping receptive field centres were statistically flat, reflecting no statistical dependence. 3. Most cell pairs consisting of transient and sustained concentric cells and having overlapping receptive field centres exhibited a correlated maintained discharge indicative of statistical dependence. The strength of the statistical dependence varied approximately inversely with the degree of overlap between the two cells comprising the cell pair. 4. Cell pairs consisting of two ON-centre cells or two OFF-centre cells and having overlapping receptive field centres possessed incremental <span class="hlt">cross-correlations</span> which were characterized by a peak centred near zero. Cell pairs consisting of an ON-centre cell with an OFF-centre and having overlapping receptive field centres possessed decremental <span class="hlt">cross-correlations</span> which were characterized by a valley centred near zero. 5. The results are consistent with the hypothesis that a noise source provides shared input to two or more retinal ganglion cells. Bipolar and photoreceptors are the most likely sources of noise responsible for the statistical dependency between retinal ganglion cells. PMID:7310736</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19346626','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19346626"><span>Application of autocorrelation and <span class="hlt">cross-correlation</span> analyses in human movement and rehabilitation research.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nelson-Wong, Erika; Howarth, Sam; Winter, David A; Callaghan, Jack P</p> <p>2009-04-01</p> <p>Technical note. To provide background theory and information and to describe relevant applications of autocorrelation and <span class="hlt">cross-correlation</span> methodology as they apply to the field of motor control in human movement and rehabilitation research. Commonly used methodologies for pattern and event recognition, determination of muscle activation timing for investigation of movement coordination, and motor control are generally difficult to implement, particularly with large datasets. A brief description of the underlying mathematical theory of correlation analyses is given, followed by 4 different examples of how this methodology is useful for research in the movement sciences. Examples demonstrating the utility of correlation analyses are presented from several different studies conducted at the University of Waterloo. Autocorrelation was used to demonstrate the presence of 60-Hz noise in an electromyography signal that was not visible in the raw data. A "top-down" paraspinal muscle activation pattern was demonstrated for healthy adults during gait, with the use of <span class="hlt">cross-correlation</span>. <span class="hlt">Cross-correlation</span> was also used to quantify coactivation of bilateral gluteus medius muscles during standing in individuals who developed low-back pain. Gender differences in gluteus medius control of mediolateral center of pressure were seen with the use of <span class="hlt">cross-correlation</span>. Autocorrelation and crosscorrelation have been shown to be an effective tool for several different applications in the movement sciences. Examples of the method's utility include noise detection within a signal, determination of relative muscle activation onsets for postural control, objective quantification of muscle coactivation, and relating muscle activations with mechanical events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1045408','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1045408"><span>The importance of transport parameter <span class="hlt">cross</span> <span class="hlt">correlations</span> in natural systems radioactive transport models</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Reimus, Paul W</p> <p>2011-01-03</p> <p>Transport parameter <span class="hlt">cross</span> <span class="hlt">correlations</span> are rarely considered in models used to predict radionuclide transport in natural systems. In this paper, it is shown that parameter <span class="hlt">cross</span> <span class="hlt">correlations</span> could have a significant impact on radionuclide transport predictions in saturated media. In fractured rock, the positive correlation between fracture apertures and groundwater residence times is shown to result in significantly less retardation due to matrix diffusion than is predicted without the correlation. The suppression of matrix diffusion is further amplified by a tendency toward larger apertures, smaller matrix diffusion coefficients, and less sorption capacity in rocks of lower matrix porosity. In a hypothetical example, strong <span class="hlt">cross</span> <span class="hlt">correlations</span> between these parameters result in a decrease in predicted radionuclide travel times of an order of magnitude or more relative to travel times calculated with uncorrelated parameters. In porous media, expected correlations between permeability, porosity, and sorption capacity also result in shorter predicted travel times than when the parameters are assumed to be uncorrelated. Individual parameter standard deviations can also have a significant influence on predicted radionuclide travel times, particularly when <span class="hlt">cross</span> <span class="hlt">correlations</span> are considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvE..94d2307O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvE..94d2307O"><span>Multifractal <span class="hlt">cross-correlation</span> effects in two-variable time series of complex network vertex observables</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>OświÈ©cimka, Paweł; Livi, Lorenzo; DroŻdŻ, Stanisław</p> <p>2016-10-01</p> <p>We investigate the scaling of the <span class="hlt">cross-correlations</span> calculated for two-variable time series containing vertex properties in the context of complex networks. Time series of such observables are obtained by means of stationary, unbiased random walks. We consider three vertex properties that provide, respectively, short-, medium-, and long-range information regarding the topological role of vertices in a given network. In order to reveal the relation between these quantities, we applied the multifractal <span class="hlt">cross-correlation</span> analysis technique, which provides information about the nonlinear effects in coupling of time series. We show that the considered network models are characterized by unique multifractal properties of the <span class="hlt">cross-correlation</span>. In particular, it is possible to distinguish between Erdös-Rényi, Barabási-Albert, and Watts-Strogatz networks on the basis of fractal <span class="hlt">cross-correlation</span>. Moreover, the analysis of protein contact networks reveals characteristics shared with both scale-free and small-world models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28287971','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28287971"><span>Fast 2D Convolutions and <span class="hlt">Cross-Correlations</span> Using Scalable Architectures.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carranza, Cesar; Llamocca, Daniel; Pattichis, Marios</p> <p>2017-05-01</p> <p>The manuscript describes fast and scalable architectures and associated algorithms for computing convolutions and <span class="hlt">cross-correlations</span>. The basic idea is to map 2D convolutions and <span class="hlt">cross-correlations</span> to a collection of 1D convolutions and <span class="hlt">cross-correlations</span> in the transform domain. This is accomplished through the use of the discrete periodic radon transform for general kernels and the use of singular value decomposition -LU decompositions for low-rank kernels. The approach uses scalable architectures that can be fitted into modern FPGA and Zynq-SOC devices. Based on different types of available resources, for P×P blocks, 2D convolutions and <span class="hlt">cross-correlations</span> can be computed in just O(P) clock cycles up to O(P(2)) clock cycles. Thus, there is a trade-off between performance and required numbers and types of resources. We provide implementations of the proposed architectures using modern programmable devices (Virtex-7 and Zynq-SOC). Based on the amounts and types of required resources, we show that the proposed approaches significantly outperform current methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..465..338H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..465..338H"><span>Oil price and exchange rate co-movements in Asian countries: Detrended <span class="hlt">cross-correlation</span> approach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hussain, Muntazir; Zebende, Gilney Figueira; Bashir, Usman; Donghong, Ding</p> <p>2017-01-01</p> <p>Most empirical literature investigates the relation between oil prices and exchange rate through different models. These models measure this relationship on two time scales (long and short terms), and often fail to observe the co-movement of these variables at different time scales. We apply a detrended <span class="hlt">cross-correlation</span> approach (DCCA) to investigate the co-movements of the oil price and exchange rate in 12 Asian countries. This model determines the co-movements of oil price and exchange rate at different time scale. The exchange rate and oil price time series indicate unit root problem. Their correlation and <span class="hlt">cross-correlation</span> are very difficult to measure. The result becomes spurious when periodic trend or unit root problem occurs in these time series. This approach measures the possible <span class="hlt">cross-correlation</span> at different time scale and controlling the unit root problem. Our empirical results support the co-movements of oil prices and exchange rate. Our results support a weak negative <span class="hlt">cross-correlation</span> between oil price and exchange rate for most Asian countries included in our sample. The results have important monetary, fiscal, inflationary, and trade policy implications for these countries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.S23D0197B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.S23D0197B"><span>Ambient Noise <span class="hlt">Cross-correlation</span> Surface Wave Tomography of the Continental United States and Alaska.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bensen, G. D.; McCoy, C.; Ritzwoller, M. H.; Levshin, A. L.; Barmin, M. P.; Shapiro, N. M.</p> <p>2006-12-01</p> <p>The recent development of surface wave tomography based on ambient noise <span class="hlt">cross-correlations</span> has provided good results on regional scales and relatively short periods less than 40 seconds. This technique however is viable at longer periods and on the continental scale. We present dispersion maps from ambient noise <span class="hlt">cross</span>- <span class="hlt">correlation</span> surface-wave tomography for the continental United States and Alaska between 10 and 60 seconds period. Using up to 2 years of data from over 250 permanent and temporary stations obtained from the IRIS DMC and the Canadian National Seismic Network we compute <span class="hlt">cross-correlations</span> for all station pairs. An automated dispersion analysis technique is applied to obtain Rayleigh wave group and phase speed curves and unacceptable measurements are removed. Dispersion curves from over 12,500 paths are retained in the continental US and about 1,000 <span class="hlt">cross-correlation</span> and earthquake paths result in Alaska. We obtain isotropic Rayleigh wave group and phase speed maps on a one half degree grid using a damped ray theoretical inversion. Compared to previous teleseismic earthquake techniques, the short period maps provide better resolution of smaller scale features, especially those in the crust. The improved path coverage also enhances resolution at longer periods compared to previous maps with better delineation of tectonic provinces. In Alaska, limited station coverage and earthquake distribution confine the results to the south-central part of the state. Preliminary azimuthally anisotropic Rayleigh wave tomography maps are also presented together with an assessment of their robustness.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/950875','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/950875"><span>Lenses in the forest: <span class="hlt">cross--correlation</span> of the Lyman-alpha flux with CMB lensing</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Vallinotto, Alberto; Das, Sudeep; Spergel, David N.; Viel, Matteo; /Trieste Observ. /INFN, Trieste</p> <p>2009-03-01</p> <p>We present a theoretical estimate for a new observable: the <span class="hlt">cross-correlation</span> between the Lyman-{alpha}-flux fluctuations in quasar (QSO) spectra and the convergence of the cosmic microwave background (CMB) as measured along the same line-of-sight. As a first step toward the assessment of its detectability, we estimate the signal-to-noise ratio using linear theory. Although the signal-to-noise is small for a single line-of-sight and peaks at somewhat smaller redshifts than those probed by the Lyman-{alpha} forest, we estimate a total signal-to-noise of 9 for <span class="hlt">cross-correlating</span> QSO spectra of SDSSIII with Planck and 20 for <span class="hlt">cross-correlating</span> with a future polarization based CMB experiment. The detection of this effect would be a direct measure of the neutral hydrogen-matter <span class="hlt">cross-correlation</span> and could provide important information on the growth of structures at large scales in a redshift range which is still poorly probed by observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10184153','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10184153"><span><span class="hlt">Function</span> analysis of the single-shell Tank Waste <span class="hlt">Retrieval</span> Manipulator System. Environmental Restoration and Waste Management Program</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Draper, J.V.</p> <p>1993-08-01</p> <p>This document lists the <span class="hlt">functions</span> likely to be performed by each proposed component of the Tank Waste <span class="hlt">Retrieval</span> Manipulator System (TWRMS) and the user <span class="hlt">functions</span> that must be performed to operate each component. While the information contained in this document is tentative because the systems are still evolving, it provides a foundation for task analysis and control room design efforts. These efforts will support the design of a test-bed control room in the near future and an operational control room later. The information in this document is based on specifications published for the TWRMS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2924932','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2924932"><span><span class="hlt">Cross-correlation</span> of instantaneous amplitudes of field potential oscillations: a straightforward method to estimate the directionality and lag between brain areas</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Adhikari, Avishek; Sigurdsson, Torfi; Topiwala, Mihir A.; Gordon, Joshua A.</p> <p>2010-01-01</p> <p>Researchers performing multi-site recordings are often interested in identifying the directionality of <span class="hlt">functional</span> connectivity and estimating lags between sites. Current techniques for determining directionality require spike trains or involve multivariate autoregressive modeling. However, it is often difficult to sample large numbers of spikes from multiple areas simultaneously, and modeling can be sensitive to noise. A simple, model-independent method to estimate directionality and lag using local field potentials (LFPs) would be of general interest. Here we describe such a method using the <span class="hlt">cross-correlation</span> of the instantaneous amplitudes of filtered LFPs. The method involves four steps. First, LFPs are band-pass filtered; second, the instantaneous amplitude of the filtered signals is calculated; third, these amplitudes are <span class="hlt">cross-correlated</span> and the lag at which the <span class="hlt">cross-correlation</span> peak occurs is determined; fourth, the distribution of lags obtained is tested to determine if it differs from zero. This method was applied to LFPs recorded from the ventral hippocampus and the medial prefrontal cortex in awake behaving mice. The results demonstrate that the hippocampus leads the mPFC, in good agreement with the time lag calculated from the phase locking of mPFC spikes to vHPC LFP oscillations in the same dataset. We also compare the amplitude <span class="hlt">cross-correlation</span> method to partial directed coherence, a commonly used multivariate autoregressive model-dependent method, and find that the former is more robust to the effects of noise. These data suggest that the <span class="hlt">cross-correlation</span> of instantaneous amplitude of filtered LFPs is a valid method to study the direction of flow of information across brain areas. PMID:20600317</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014MPLB...2850090C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014MPLB...2850090C"><span>Multifractal detrended <span class="hlt">cross-correlation</span> between the Chinese domestic and international gold markets based on DCCA and DMCA methods</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cao, Guangxi; Han, Yan; Chen, Yuemeng; Yang, Chunxia</p> <p>2014-05-01</p> <p>Based on the daily price data of Shanghai and London gold spot markets, we applied detrended <span class="hlt">cross-correlation</span> analysis (DCCA) and detrended moving average <span class="hlt">cross-correlation</span> analysis (DMCA) methods to quantify power-law <span class="hlt">cross-correlation</span> between domestic and international gold markets. Results show that the <span class="hlt">cross-correlations</span> between the Chinese domestic and international gold spot markets are multifractal. Furthermore, forward DMCA and backward DMCA seems to outperform DCCA and centered DMCA for short-range gold series, which confirms the comparison results of short-range artificial data in L. Y. He and S. P. Chen [Physica A 390 (2011) 3806-3814]. Finally, we analyzed the local multifractal characteristics of the <span class="hlt">cross-correlation</span> between Chinese domestic and international gold markets. We show that multifractal characteristics of the <span class="hlt">cross-correlation</span> between the Chinese domestic and international gold markets are time-varying and that multifractal characteristics were strengthened by the financial crisis in 2007-2008.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.458.3399W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.458.3399W"><span>Intensity mapping <span class="hlt">cross-correlations</span>: connecting the largest scales to galaxy evolution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wolz, L.; Tonini, C.; Blake, C.; Wyithe, J. S. B.</p> <p>2016-05-01</p> <p>Intensity mapping of the neutral hydrogen (H I) is a new observational tool to efficiently map the large-scale structure over wide redshift ranges. The <span class="hlt">cross-correlation</span> of intensity maps with galaxy surveys is a robust measure of the cosmological power spectrum and the H I content of galaxies which diminishes systematics caused by instrumental effects and foreground removal. We examine the <span class="hlt">cross-correlation</span> signature at redshift 0.9 using a semi-analytical galaxy formation model in order to model the H I gas of galaxies as well as their optical magnitudes. We determine the scale-dependent clustering of the <span class="hlt">cross-correlation</span> power for different types of galaxies determined by their colours, which act as a proxy for their star formation activity. We find that the <span class="hlt">cross-correlation</span> coefficient with H I density for red quiescent galaxies falls off more quickly on smaller scales k > 0.2 h Mpc-1 than for blue star-forming galaxies. Additionally, we create a mock catalogue of highly star-forming galaxies to mimic the WiggleZ Dark Energy Survey, and use this to predict existing and future measurements using data from the Green Bank telescope and Parkes telescope. We find that the cross-power of highly star-forming galaxies shows a higher clustering on small scales than any other galaxy type and that this significantly alters the power spectrum shape on scales k > 0.2 h Mpc-1. We show that the <span class="hlt">cross-correlation</span> coefficient is not negligible when interpreting the cosmological cross-power spectrum and additionally contains information about the H I content of the optically selected galaxies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6748P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6748P"><span><span class="hlt">Cross</span> <span class="hlt">correlation</span> of chemical profiles in minerals: insights into the architecture of magmatic reservoirs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Probst, Line; Caricchi, Luca; Gander, Martin; Wallace, Glenn</p> <p>2016-04-01</p> <p>Analysis of chemical zoning in minerals offers the opportunity to reconstruct the pre-eruptive conditions and the temporal evolution of magmatic reservoirs. The chemical composition of minerals is a <span class="hlt">function</span> of the thermodynamic conditions of the reservoir from which they grow and therefore minerals record the evolution and variation of residual melt chemistry and intensive parameters within the magmatic system. A quantitative approach is required to determine if similar crystals actually shared a portion of their crystallisation history. These analyses are in many cases extremely time consuming and rather expensive. Therefore, it is not always possible to analyse a statically significant number of crystals, especially within their textural context in thin sections and that is the main reason to build automated methods. We are presenting a numerical <span class="hlt">cross-correlation</span> method that compares the zonation pattern of minerals to identify if they share the totality or part of their growth history. We modified the method first developed by Wallace and Bergantz (2004) to compare profiles in minerals also from samples collected in different outcrops and that can be used for any dataset (i.e. geochemical proxies in stratigraphic sections). The main purpose of this method is to objectively compare chemical profiles in minerals (collected by electron microprobe, LA-ICP-MS or cathodoluminescence images) and quantify their degree of similarity. For this purpose, we use a well-known mathematical tool: the <span class="hlt">cross</span> <span class="hlt">correlation</span> which is a way of quantifying the difference between two given signals at a given position. Once our program was built, we performed tests using a set of synthetic profiles, profiles acquired along different transects of the same mineral and also on different minerals. Finally we applied our program to about 100 zircons from Kilgore Tuff, Heise Volcanic Field (USA) collected at different stratigraphic levels in two different outcrops. The correlation shows that</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19642890','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19642890"><span>Word <span class="hlt">retrieval</span> failures in old age: the relationship between structure and <span class="hlt">function</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Shafto, Meredith A; Stamatakis, Emmanuel A; Tam, Phyllis P; Tyler, L K</p> <p>2010-07-01</p> <p>A common complaint of normal aging is the increase in word-finding failures such as tip-of-the-tongue states (TOTs). Behavioral research identifies TOTs as phonological <span class="hlt">retrieval</span> failures, and recent findings [Shafto, M. A., Burke, D. M., Stamatakis, E. A., Tam, P., & Tyler, L. K. On the tip-of-the-tongue: Neural correlates of increased word-finding failures in normal aging. Journal of Cognitive Neuroscience, 19, 2060-2070, 2007] link age-related increases in TOTs to atrophy in left insula, a region implicated in phonological production. Here, younger and older adults performed a picture naming task in the fMRI scanner. During successful naming, left insula activity was not affected by age or gray matter integrity. Age differences only emerged during TOTs, with younger but not older adults generating a "boost" of activity during TOTs compared to successful naming. Older adults also had less activity than younger adults during TOTs compared to "don't know" responses, and across all participants, less TOT activity was affiliated with lower gray matter density. For older adults, lower levels of activity during TOTs accompanied higher TOT rates, supporting the role of an age-related neural mechanism impacting older more than younger adults. Results support a neural account of word <span class="hlt">retrieval</span> in old age wherein, despite widespread age-related atrophy, word production processes are not universally impacted by age. However, atrophy undermines older adults' ability to modulate neural responses needed to overcome <span class="hlt">retrieval</span> failures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012SPIE.8314E..06Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012SPIE.8314E..06Y"><span>Fully automated prostate segmentation in 3D MR based on normalized gradient fields <span class="hlt">cross-correlation</span> initialization and LOGISMOS refinement</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yin, Yin; Fotin, Sergei V.; Periaswamy, Senthil; Kunz, Justin; Haldankar, Hrishikesh; Muradyan, Naira; Cornud, François; Turkbey, Baris; Choyke, Peter</p> <p>2012-02-01</p> <p>Manual delineation of the prostate is a challenging task for a clinician due to its complex and irregular shape. Furthermore, the need for precisely targeting the prostate boundary continues to grow. Planning for radiation therapy, MR-ultrasound fusion for image-guided biopsy, multi-parametric MRI tissue characterization, and context-based organ <span class="hlt">retrieval</span> are examples where accurate prostate delineation can play a critical role in a successful patient outcome. Therefore, a robust automated full prostate segmentation system is desired. In this paper, we present an automated prostate segmentation system for 3D MR images. In this system, the prostate is segmented in two steps: the prostate displacement and size are first detected, and then the boundary is refined by a shape model. The detection approach is based on normalized gradient fields <span class="hlt">cross-correlation</span>. This approach is fast, robust to intensity variation and provides good accuracy to initialize a prostate mean shape model. The refinement model is based on a graph-search based framework, which contains both shape and topology information during deformation. We generated the graph cost using trained classifiers and used coarse-to-fine search and region-specific classifier training. The proposed algorithm was developed using 261 training images and tested on another 290 cases. The segmentation performance using mean DSC ranging from 0.89 to 0.91 depending on the evaluation subset demonstrates state of the art performance. Running time for the system is about 20 to 40 seconds depending on image size and resolution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PEPI..265...92C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PEPI..265...92C"><span>Inferences on the lithospheric structure of Campi Flegrei District (southern Italy) from seismic noise <span class="hlt">cross-correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Costanzo, M. R.; Nunziata, C.</p> <p>2017-04-01</p> <p>Lithospheric VS models are defined in the Campi Flegrei District (southern Italy) through the non-linear inversion of the group velocity dispersion curves of fundamental-mode Rayleigh waves extracted from ambient noise <span class="hlt">cross-correlations</span> between two receivers, and the regional group and phase velocities of the Italian cellular lithospheric model (1° × 1° cells). Four paths are investigated, of which one (ISCHIA-MIS) across two adjoining cells. The distribution of VS shows a pyroclastic covering with VS increasing from 0.3-0.7 km/s to 2.1 km/s. It rests on a lava or carbonate basement, about 5-6 km thick, with VS increasing from 2.1 km/s to 3.1 km/s at about 2 km of depth and rising to ∼0.6 km towards the island of Procida. A metamorphic layer is detected at an average depth of 7.7 km with VS of 3.8-3.9 km/s, about 5 km thick, overlying a low velocity layer (VS of 3.5 km/s) at about 11-12 km of depth. The VS model along the ISCHIA-MIS path, as average of the models obtained by combining local and regional dispersion data of the two adjoining cells, is well consistent with the other paths. The Moho discontinuity is <span class="hlt">retrieved</span> at about 23 km of depth with VS of 4.2 km/s.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.T21A0354O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.T21A0354O"><span>A new hypocenter determination method using the summation of waveform <span class="hlt">cross</span>- <span class="hlt">correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ohta, K.; Ide, S.</p> <p>2007-12-01</p> <p>Deep low frequency tremor is a swarm activity of low-frequency earthquakes (LFEs) at least in the western Shikoku, Japan [Shelly et al., 2007]. LFEs are considered as shear slip on the plate interface because their focal mechanism has a low-angle thrust fault plane [Ide et al., 2007] and because precisely determined hypocenters are located on the plate interface [Shelly et al., 2006]. However, it is not obvious whether LFEs in other regions have the same characteristics. For example, in the Tokai region and the Kii Peninsula the hypocentral depths of LFEs determined by Japan Meteorological Agency are widely distributed from 20 to 50 km. Precise hypocenters of LFEs are essential for discussion on regional diversity of low frequency tremor. The low signal-to-noise (S/N) ratio of LFE records can be a source of larger estimated error in the hypocenter determination. Although waveform <span class="hlt">cross-correlation</span> is a useful tool for precise hypocenter determination, it is not reliable in the case of the low S/N ratio because the value of <span class="hlt">cross-correlation</span> is generally small. However, Shelly et al. [2007] showed that the summation of waveform <span class="hlt">cross-correlation</span> for many stations can enhance event detectability. Similarly, using the summation of waveform <span class="hlt">cross-correlation</span>, we develop a new hypocenter determination method that is less sensitive to noises. We apply this method to LFEs in the Tokai region and the Kii Peninsula. The data are 3-component velocity records from the NIED Hi-net, bandpass filtered between 2-8Hz. We first determine the relative hypocenral location between a pair of LFEs in a event list. Assuming a layered structure, we calculate theoretical differential travel times of body waves relative to the arrival times from the one event, After shifting the records of the other event using these differential travel times, we calculate the summation of the waveform <span class="hlt">cross-correlation</span> coefficient between two events for all stations. The relative location is determined to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/9487073','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/9487073"><span>[A <span class="hlt">cross-correlational</span> analysis of the bioelectrical activity of muscle antagonists in studying human voluntary motor activity in certain forms of motor disorders].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sheliakin, A M; Preobrazhenskaia, I G; Bogdanov, O V</p> <p>1997-09-01</p> <p>In healthy [correction of beglth] subjects, patients with children's cerebral palsy and spinal cord disturbances, the <span class="hlt">cross-correlation</span> <span class="hlt">function</span> of the EMG at the initial phase of voluntary movement and at the phase of static voluntary tension revealed some mechanisms maintaining coordinated interrelations among antagonist muscles at different phases. A new approach is suggested for estimation of the electromyogram and for a finer diagnosis of the CNS lesions at different levels.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/917266','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/917266"><span><span class="hlt">Cross-correlation</span> Weak Lensing of SDSS Galaxy Clusters III: Mass-to-light Ratios</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sheldon, Erin S.; Johnston, David E.; Masjedi, Morad; McKay, Timothy A.; Blanton, Michael R.; Scranton, Ryan; Wechsler, Risa H.; Koester, Ben P.; Hansen, Sarah M.; Frieman, Joshua A.; Annis, James</p> <p>2007-09-28</p> <p>We present measurements of the excess mass-to-light ratio measured around MaxBCG galaxy clusters observed in the SDSS. This red sequence cluster sample includes objects from small groups with M{sub 200} {approx} 5 x 10{sup 12}h{sup -1}M{sub {circle_dot}} to clusters with M{sub 200} {approx} 5 x 10{sup 15}h{sup -1}M{sub {circle_dot}}. Using <span class="hlt">cross-correlation</span> weak lensing, we measure the excess mass density profile above the universal mean {Delta}{yields}(r) = {rho}(r) -- {bar {rho}} for clusters in bins of richness and optical luminosity. We also measure the excess {sup 0.25}i-band luminosity density {Delta}{ell}(r) = {ell}(r) -- {bar {ell}}. For both mass and light, we de-project the profiles to produce 3D mass and light profiles over scales from 25h{sup -1} kpc to 22h{sup -1} Mpc. From these profiles we calculate the cumulative excess mass {Delta}M(r) and excess light {Delta}L(r) as a <span class="hlt">function</span> of separation from the BCG. On small scales, where {rho}(r) >> {bar {rho}}, the integrated mass-to-light profile ({Delta}M/{Delta}L)(r) may be interpreted as the cluster mass-to-light ratio. We find the ({Delta}M/{Delta}L){sub 200}, the mass-to-light ratio within r{sub 200}, scales with cluster mass as a power law with index 0.33{+-}0.02. On large scales, where {rho}(r) {approx} {bar {rho}}, the {Delta}M/{Delta}L approaches an asymptotic value independent of scale or cluster richness. For small groups, the mean ({Delta}M/{Delta}L){sub 200} is much smaller than the asymptotic value, while for large clusters ({Delta}M/{Delta}L)200 is consistent with the asymptotic value. This asymptotic value should be proportional to the mean mass-to-light ratio of the universe {l_angle}M/L{r_angle}. We find {l_angle}M/L{r_angle} b{sup -2}{sub M/L} = 362 {+-} 54h measured in the {sup 0.25}i-bandpass. The parameter b{sup 2}{sub M/L} is primarily a <span class="hlt">function</span> of the bias of the L {approx}< L* galaxies used as light tracers, and should be of order unity. Multiplying by the luminosity density in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21371819','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21371819"><span><span class="hlt">CROSS-CORRELATION</span> WEAK LENSING OF SDSS GALAXY CLUSTERS. III. MASS-TO-LIGHT RATIOS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sheldon, Erin S.; Johnston, David E.; Masjedi, Morad; Blanton, Michael R.; McKay, Timothy A.; Scranton, Ryan; Wechsler, Risa H.; Koester, Benjamin P.; Hansen, Sarah M.; Frieman, Joshua A.; Annis, James</p> <p>2009-10-01</p> <p>We present measurements of the excess mass-to-light ratio (M/L) measured around MaxBCG galaxy clusters observed in the Sloan Digital Sky Survey. This red-sequence cluster sample includes objects from small groups with M {sub 200} approx 5 x 10{sup 12} h {sup -1} M {sub sun} to clusters with M {sub 200} approx 10{sup 15} h {sup -1} M {sub sun}. Using <span class="hlt">cross-correlation</span> weak lensing, we measure the excess mass density profile above the universal mean DELTArho(r)=rho(r)-rho-bar for clusters in bins of richness and optical luminosity. We also measure the excess luminosity density DELTAl(r)=l(r)-l-bar measured in the z = 0.25 i band. For both mass and light, we de-project the profiles to produce three-dimensional mass and light profiles over scales from 25 h {sup -1} kpc to 22 h {sup -1} Mpc. From these profiles we calculate the cumulative excess mass DELTAM(r) and excess light DELTAL(r) as a <span class="hlt">function</span> of separation from the BCG. On small scales, where rho(r)>>rho-bar, the integrated mass-to-light profile (DELTAM/DELTAL)(r) may be interpreted as the cluster M/L. We find the (DELTAM/DELTAL){sub 200}, the M/L within r {sub 200}, scales with cluster mass as a power law with index 0.33 +- 0.02. On large scales, where rho(r)approxrho-bar, the DELTAM/DELTAL approaches an asymptotic value independent of cluster richness. For small groups, the mean (DELTAM/DELTAL){sub 200} is much smaller than the asymptotic value, while for large clusters (DELTAM/DELTAL){sub 200} is consistent with the asymptotic value. This asymptotic value should be proportional to the mean M/L of the universe (M/L). We find (M/L)b{sup -2} {sub M/L} = 362 +- 54h (statistical). There is additional uncertainty in the overall calibration at the approx10% level. The parameter b {sup 2} {sub M/L} is primarily a <span class="hlt">function</span> of the bias of the L approx< L {sub *} galaxies used as light tracers, and should be of order unity. Multiplying by the luminosity density in the same bandpass we find OMEGA {sub m}b{sup -2} {sub M</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21382387','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21382387"><span>Temporally and <span class="hlt">functionally</span> dissociable <span class="hlt">retrieval</span> processing operations revealed by event-related potentials.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cruse, Damian; Wilding, Edward L</p> <p>2011-06-01</p> <p>In a pair of recent studies, frontally distributed event-related potential (ERP) indices of two distinct post-<span class="hlt">retrieval</span> processes were identified. It has been proposed that one of these processes operates over any kinds of task relevant information in service of task demands, while the other operates selectively over recovered contextual (episodic) information. The experiment described here was designed to test this account, by requiring <span class="hlt">retrieval</span> of different kinds of contextual information to that required in previous relevant studies. Participants heard words spoken in either a male or female voice at study and ERPs were acquired at test where all words were presented visually. Half of the test words had been spoken at study. Participants first made an old/new judgment, distinguishing via key press between studied and unstudied words. For words judged 'old', participants indicated the voice in which the word had been spoken at study, and their confidence (high/low) in the voice judgment. There was evidence for only one of the two frontal old/new effects that had been identified in the previous studies. One possibility is that the ERP effect in previous studies that was tied specifically to recollection reflects processes operating over only some kinds of contextual information. An alternative is that the index reflects processes that are engaged primarily when there are few contextual features that distinguish between studied stimuli.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JPhCS.305a2005T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JPhCS.305a2005T"><span>A Method for Vibration-Based Structural Interrogation and Health Monitoring Based on Signal <span class="hlt">Cross-Correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Trendafilova, I.</p> <p>2011-07-01</p> <p>Vibration-based structural interrogation and health monitoring is a field which is concerned with the estimation of the current state of a structure or a component from its vibration response with regards to its ability to perform its intended <span class="hlt">function</span> appropriately. One way to approach this problem is through damage features extracted from the measured structural vibration response. This paper suggests to use a new concept for the purposes of vibration-based health monitoring. The correlation between two signals, an input and an output, measured on the structure is used to develop a damage indicator. The paper investigates the applicability of the signal <span class="hlt">cross-correlation</span> and a nonlinear alternative, the average mutual information between the two signals, for the purposes of structural health monitoring and damage assessment. The suggested methodology is applied and demonstrated for delamination detection in a composite beam.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26627750','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26627750"><span>Measurement of circumferential Lamb waves using a line-focus poly(vinylidene fluoride) transducer and <span class="hlt">cross</span> <span class="hlt">correlation</span> waveform analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lin, Chun-I; Lu, Yan; He, Cunfu; Song, Guorong; Lee, Yung-Chun</p> <p>2015-11-01</p> <p>This paper presents a method for measuring circumferential Lamb waves propagating on a cylindrically curved thin plate. The measurement is carried out using a wideband and line-focused poly(vinylidene fluoride) transducer along with a defocusing waveform measurement method. After synthesizing the acquired waveforms, interference patterns can be obtained and a <span class="hlt">cross</span> <span class="hlt">correlation</span> method is developed to accurately extract the wave velocity as a <span class="hlt">function</span> of wave frequency. Using three stainless steel thin plates of different thicknesses (100, 150, and 300 μm) and a radius of curvature of 10 mm, dispersion curves for several fundamental and higher order modes of circumferential Lamb waves are simultaneously determined. Theoretical dispersion curves are also calculated and compared with their experimental counterparts. Very good agreements are observed, which concludes the measurement accuracy of this measurement method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhCS.842a2018C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhCS.842a2018C"><span>Structural damage continuous monitoring by using a data driven approach based on principal component analysis and <span class="hlt">cross-correlation</span> analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Camacho-Navarro, Jhonatan; Ruiz, Magda; Villamizar, Rodolfo; Mujica, Luis; Moreno-Beltrán, Gustavo; Quiroga, Jabid</p> <p>2017-05-01</p> <p>Continuous monitoring for damage detection in structural assessment comprises implementation of low cost equipment and efficient algorithms. This work describes the stages involved in the design of a methodology with high feasibility to be used in continuous damage assessment. Specifically, an algorithm based on a data-driven approach by using principal component analysis and pre-processing acquired signals by means of <span class="hlt">cross-correlation</span> <span class="hlt">functions</span>, is discussed. A carbon steel pipe section and a laboratory tower were used as test structures in order to demonstrate the feasibility of the methodology to detect abrupt changes in the structural response when damages occur. Two types of damage cases are studied: crack and leak for each structure, respectively. Experimental results show that the methodology is promising in the continuous monitoring of real structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820046843&hterms=Palestine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DPalestine','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820046843&hterms=Palestine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DPalestine"><span><span class="hlt">Cross</span> <span class="hlt">correlation</span> analysis of medium energy gamma rays for the Northern Hemisphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Long, J.; Zanrosso, E.; Zych, A. D.; White, R. S.</p> <p>1982-01-01</p> <p>In the <span class="hlt">cross</span> <span class="hlt">correlation</span> method the observed gamma rays are compared with the expected telescope response for a discrete celestial source. The background consists of the atmospheric flux with its maximum near the horizon, the cosmic diffuse flux, and neutron induced gamma rays in the telescope. In sharp contrast to the background, a celestial source produces an asymmetric azimuthal response which varies predictably in time as the source moves through the telescope's aperture. This contrast serves as the basis of the <span class="hlt">cross</span> <span class="hlt">correlation</span> technique. Continuous data of 47.5 hr were obtained during a balloon flight from Palestine, TX from 0930 UT on September 30, 1978 to 2300 UT on October 1, 1978. The Crab Nebula-Anticenter region was observed on two consecutive days. A number of other medium energy source candidates also crossed the field-of-view. The obtained results are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770010886','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770010886"><span>Acoustic source location in a jet-blown flap using a <span class="hlt">cross-correlation</span> technique</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Becker, R. S.; Maus, J. R.</p> <p>1977-01-01</p> <p>The acoustic source strength distribution in a turbulent flow field was measured for two far field microphones at 45 deg above and below the plane of the flap surface. A processed signal from an inclined hot-film anemometry probe was <span class="hlt">cross</span> <span class="hlt">correlated</span> with the signal from the appropriate far field microphone. The contribution made by the sources associated with the fluctuating pressure on the flap surface to the sound received at far field microphone was estimated by <span class="hlt">cross</span> <span class="hlt">correlating</span> the processed signals of microphones which were embedded in the flap surface with the far field microphone signals. In addition, detailed fluid dynamic measurements were made in the flow field of the jet flap using dual sensor hot-film anemometry probes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SSCom.258...25C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SSCom.258...25C"><span>Noise <span class="hlt">cross-correlation</span> and Cooper pair splitting efficiency in multi-teminal superconductor junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Celis Gil, J. A.; Gomez P., S.; Herrera, William J.</p> <p>2017-05-01</p> <p>We analyze the non-local shot noise in a multi-terminal junction formed by two Normal metal leads connected to one superconductor. Using the cross Fano factor and the shot noise, we calculate the efficiency of the Cooper pair splitting. The method is applied to d-wave and iron based superconductors. We determine that the contributions to the noise <span class="hlt">cross-correlation</span> are due to crossed Andreev reflections (CAR), elastic cotunneling, quasiparticles transmission and local Andreev reflections. In the tunneling limit, the CAR contribute positively to the noise <span class="hlt">cross-correlation</span> whereas the other processes contribute negatively. Depending on the pair potential symmetry, the CAR are the dominant processes, giving as a result a high efficiency for Cooper pair split. We propose the use of the Fano factor to test the efficiency of a Cooper pair splitter device.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE.9845E..05L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE.9845E..05L"><span><span class="hlt">Cross-correlation</span> and image alignment for multi-band IR sensors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lu, Thomas; Chao, Tien-Hsin; Chen, Kang (Frank); Luong, Andrew; Dewees, Mallory; Yan, Xinyi; Chow, Edward; Torres, Gilbert</p> <p>2016-04-01</p> <p>We present the development of a <span class="hlt">cross-correlation</span> algorithm for correlating objects in the long wave, mid wave and short wave Infrared sensor arrays. The goal is to align the images in the multisensor suite by correlating multiple key features in the images. Due to the wavelength differences, the object appears very differently in the sensor images even the sensors focus on the same object. In order to perform accurate correlation of the same object in the multi-band images, we perform image processing on the images so that the features of the object become similar to each other. Fourier domain band pass filters are used to enhance the images. Mexican Hat and Gaussian Derivative Wavelets are used to further enhance the features of the object. A Python based QT graphical user interface has been implemented to carry out the process. We show reliable results of the <span class="hlt">cross-correlation</span> of the objects in multiple band videos.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PApGe.171..439B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PApGe.171..439B"><span>Perspectives of <span class="hlt">Cross-Correlation</span> in Seismic Monitoring at the International Data Centre</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bobrov, Dmitry; Kitov, Ivan; Zerbo, Lassina</p> <p>2014-03-01</p> <p>We demonstrate that several techniques based on waveform <span class="hlt">cross-correlation</span> are able to significantly reduce the detection threshold of seismic sources worldwide and to improve the reliability of arrivals by a more accurate estimation of their defining parameters. A master event and the events it can find using waveform <span class="hlt">cross-correlation</span> at array stations of the International Monitoring System (IMS) have to be close. For the purposes of the International Data Centre (IDC), one can use the spatial closeness of the master and slave events in order to construct a new automatic processing pipeline: all qualified arrivals detected using <span class="hlt">cross-correlation</span> are associated with events matching the current IDC event definition criteria (EDC) in a local association procedure. Considering the repeating character of global seismicity, more than 90 % of events in the reviewed event bulletin (REB) can be built in this automatic processing. Due to the reduced detection threshold, waveform <span class="hlt">cross-correlation</span> may increase the number of valid REB events by a factor of 1.5-2.0. Therefore, the new pipeline may produce a more comprehensive bulletin than the current pipeline—the goal of seismic monitoring. The analysts' experience with the <span class="hlt">cross</span> <span class="hlt">correlation</span> event list (XSEL) shows that the workload of interactive processing might be reduced by a factor of two or even more. Since <span class="hlt">cross-correlation</span> produces a comprehensive list of detections for a given master event, no additional arrivals from primary stations are expected to be associated with the XSEL events. The number of false alarms, relative to the number of events rejected from the standard event list 3 (SEL3) in the current interactive processing—can also be reduced by the use of several powerful filters. The principal filter is the difference between the arrival times of the master and newly built events at three or more primary stations, which should lie in a narrow range of a few seconds. In this study, one event at a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.S53C2520S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.S53C2520S"><span>Detecting small scale heterogeneities in the crust from ambient noise <span class="hlt">cross-correlation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, W.; Fu, L.</p> <p>2012-12-01</p> <p>Ambient noise <span class="hlt">cross-correlation</span> is extensively applied to obtain the surface wave dispersion, and further to study the structures of the crust and the upper mantle. In recent years, many applications of the ambient noise tomography are reported in many locations, e.g., California, Europe, New Zealand, Tibet, and even in the Antarctica. The scale is regional or even continental. However, the applications of the method in detecting small scale heterogeneities are paid little attention. Small scale heterogeneities may be important to monitor/predict activities of volcano. This is concluded from the fact activities of volcano will result in stress variations. Correspondingly, the velocity distribution, i.e., heterogeneities, will change. Here, we will try to extend the ambient noise <span class="hlt">cross-correlation</span> method to study small heterogeneities in the crust.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..463..320F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..463..320F"><span>Does the Euro crisis change the <span class="hlt">cross-correlation</span> pattern between bank shares and national indexes?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ferreira, Paulo</p> <p>2016-12-01</p> <p>The objective of this paper is to analyze if the Euro crisis, which started in 2009, changes the <span class="hlt">cross-correlation</span> pattern of bank shares with the national stock indexes in both in Eurozone and non-Eurozone countries. We study all banks listed in the main stock indexes of European Union countries, applying the detrended <span class="hlt">cross-correlation</span> coefficient. An increase in the correlation indicates that the banking sector now has a greater influence in the national index, while a decrease in the correlation means the opposite. Our results show that 19 of the 39 banks analyzed in the Eurozone increased their correlation with national indexes, whilst in the non-Eurozone countries this happened with 14 of the 24 studied banks. While some authors argue that the crisis may have been aggravated by the weight of banks in the economy, Eurozone policy makers should pay attention to this feature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1820h0011L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1820h0011L"><span>Estimation of TOA based MUSIC algorithm and <span class="hlt">cross</span> <span class="hlt">correlation</span> algorithm of appropriate interval</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, Wei; Liu, Jun; Zhou, Yineng; Huang, Jiyan</p> <p>2017-03-01</p> <p>Localization of mobile station (MS) has now gained considerable attention due to its wide applications in military, environmental, health and commercial systems. Phrase angle and encode data of MSK system model are two critical parameters in time-of-arrival (TOA) localization technique; nevertheless, precise value of phrase angle and encode data are not easy to achieved in general. In order to meet the actual situation, we should consider the condition that phase angle and encode data is unknown. In this paper, a novel TOA localization method, which combine MUSIC algorithm and <span class="hlt">cross</span> <span class="hlt">correlation</span> algorithm in an appropriate interval, is proposed. Simulations show that the proposed method has better performance than music algorithm and <span class="hlt">cross</span> <span class="hlt">correlation</span> algorithm of the whole interval.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyA..444..163M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyA..444..163M"><span>Efficiency and <span class="hlt">cross-correlation</span> in equity market during global financial crisis: Evidence from China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, Pengcheng; Li, Daye; Li, Shuo</p> <p>2016-02-01</p> <p>Using one minute high-frequency data of the Shanghai Composite Index (SHCI) and the Shenzhen Composite Index (SZCI) (2007-2008), we employ the detrended fluctuation analysis (DFA) and the detrended <span class="hlt">cross</span> <span class="hlt">correlation</span> analysis (DCCA) with rolling window approach to observe the evolution of market efficiency and <span class="hlt">cross-correlation</span> in pre-crisis and crisis period. Considering the fat-tail distribution of return time series, statistical test based on shuffling method is conducted to verify the null hypothesis of no long-term dependence. Our empirical research displays three main findings. First Shanghai equity market efficiency deteriorated while Shenzhen equity market efficiency improved with the advent of financial crisis. Second the highly positive dependence between SHCI and SZCI varies with time scale. Third financial crisis saw a significant increase of dependence between SHCI and SZCI at shorter time scales but a lack of significant change at longer time scales, providing evidence of contagion and absence of interdependence during crisis.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE10155E..1HH','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE10155E..1HH"><span>Vibration measurement based on the optical <span class="hlt">cross-correlation</span> technique with femtosecond pulsed laser</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Han, Jibo; Wu, Tengfei; Zhao, Chunbo; Li, Shuyi</p> <p>2016-10-01</p> <p>Two vibration measurement methods with femtosecond pulsed laser based on the optical <span class="hlt">cross-correlation</span> technique are presented independently in this paper. The balanced optical <span class="hlt">cross-correlation</span> technique can reflect the time jitter between the reference pluses and measurement pluses by detecting second harmonic signals using type II phase-matched nonlinear crystal and balanced amplified photo-detectors. In the first method, with the purpose of attaining the vibration displacement, the time difference of the reference pulses relative to the measurement pluses can be measured using single femtosecond pulsed laser. In the second method, there are a couple of femtosecond pulsed lasers with high pulse repetition frequency. Vibration displacement associated with cavity length can be calculated by means of precisely measuring the pulse repetition frequency. The results show that the range of measurement attains ±150μm for a 500fs pulse. These methods will be suited for vibration displacement measurement, including laboratory use, field testing and industrial application.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1983ITCom..31..701F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1983ITCom..31..701F"><span>XPSK - A new <span class="hlt">cross-correlated</span> phase-shift keying modulation technique</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feher, K.; Kato, S.</p> <p>1983-05-01</p> <p>A new modulation technique, <span class="hlt">cross-correlated</span> phase-shift keying (XPSK), has been developed for the bandwidth and power efficient digital transmission. The modulation scheme proposed here, in which a controlled amount of <span class="hlt">cross</span> <span class="hlt">correlation</span> is introduced between the in-phase and quadrature channels, has improved the envelope fluctuation of the IJF-OQPSK (QORC) modulation scheme from 3 dB to approximately O dB. Therefore, in nonlinear channels, the power spectrum characteristics of XPSK are better than those of IJF-OQPSK. The Pe performance degradation of the XPSK scheme is within 1.15 dB of the theoretical linear channel performance of QPSK systems. The power spectra of XPSK signal can be controlled by adjusting the amplitude parameter according to the nonlinearity of a specific system to get minimum Pe degradation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JPSJ...82h3801Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JPSJ...82h3801Y"><span>Random Matrix Theory Analysis of <span class="hlt">Cross</span> <span class="hlt">Correlations</span> in Molecular Dynamics Simulations of Macro-Biomolecules</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamanaka, Masanori</p> <p>2013-08-01</p> <p>We apply the random matrix theory to analyze the molecular dynamics simulation of macromolecules, such as proteins. The eigensystem of the <span class="hlt">cross-correlation</span> matrix for the time series of the atomic coordinates is analyzed. We study a data set with seven different sampling intervals to observe the characteristic motion at each time scale. In all cases, the unfolded eigenvalue spacings are in agreement with the predictions of random matrix theory. In the short-time scale, the <span class="hlt">cross-correlation</span> matrix has the universal properties of the Gaussian orthogonal ensemble. The eigenvalue distribution and inverse participation ratio have a crossover behavior between the universal and nonuniversal classes, which is distinct from the known results such as the financial time series. Analyzing the inverse participation ratio, we extract the correlated cluster of atoms and decompose it to subclusters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SPIE.8924E..1JW','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SPIE.8924E..1JW"><span>A <span class="hlt">cross-correlation</span> based fiber optic white-light interferometry with wavelet transform denoising</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Zhen; Jiang, Yi; Ding, Wenhui; Gao, Ran</p> <p>2013-09-01</p> <p>A fiber optic white-light interferometry based on <span class="hlt">cross-correlation</span> calculation is presented. The detected white-light spectrum signal of fiber optic extrinsic Fabry-Perot interferometric (EFPI) sensor is firstly decomposed by discrete wavelet transform for denoising before interrogating the cavity length of the EFPI sensor. In measurement experiment, the <span class="hlt">cross-correlation</span> algorithm with multiple-level calculations is performed both for achieving the high measurement resolution and for improving the efficiency of the measurement. The experimental results show that the variation range of the measurement results was 1.265 nm, and the standard deviation of the measurement results can reach 0.375 nm when an EFPI sensor with cavity length of 1500 μm was interrogated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016A%26A...593A..15D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016A%26A...593A..15D"><span>Optimal cosmic microwave background map-making in the presence of <span class="hlt">cross-correlated</span> noise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Gasperis, G.; Buzzelli, A.; Cabella, P.; de Bernardis, P.; Vittorio, N.</p> <p>2016-08-01</p> <p>Aims: We present an extension of the ROMA map-making algorithm for the generation of optimal cosmic microwave background polarization maps. The new code allows for a possible <span class="hlt">cross-correlated</span> noise component among the detectors of a CMB experiment. A promising application is the forthcoming LSPE balloon-borne experiment, which is devoted to the accurate observation of CMB polarization at large angular scales. Methods: We generalized the noise covariance matrix in time domain to account for all the off-diagonal terms due to the detector cross-talk. Hence, we performed preliminary forecasts of the LSPE-SWIPE instrument. Results: We found that considering the noise <span class="hlt">cross-correlation</span> among the detectors results in a more realistic estimate of the angular power spectra. In particular, the extended ROMA algorithm has provided a considerable reduction of the spectra error bars. We expect that this improvement could be crucial in constraining the B-mode polarization at the largest scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.738a2077T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.738a2077T"><span>Dynamical Analysis of Stock Market Instability by <span class="hlt">Cross-correlation</span> Matrix</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takaishi, Tetsuya</p> <p>2016-08-01</p> <p>We study stock market instability by using <span class="hlt">cross-correlations</span> constructed from the return time series of 366 stocks traded on the Tokyo Stock Exchange from January 5, 1998 to December 30, 2013. To investigate the dynamical evolution of the <span class="hlt">cross-correlations</span>, crosscorrelation matrices are calculated with a rolling window of 400 days. To quantify the volatile market stages where the potential risk is high, we apply the principal components analysis and measure the cumulative risk fraction (CRF), which is the system variance associated with the first few principal components. From the CRF, we detected three volatile market stages corresponding to the bankruptcy of Lehman Brothers, the 2011 Tohoku Region Pacific Coast Earthquake, and the FRB QE3 reduction observation in the study period. We further apply the random matrix theory for the risk analysis and find that the first eigenvector is more equally de-localized when the market is volatile.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120014585','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120014585"><span>Background Noise Reduction Using Adaptive Noise Cancellation Determined by the <span class="hlt">Cross-Correlation</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Spalt, Taylor B.; Brooks, Thomas F.; Fuller, Christopher R.</p> <p>2012-01-01</p> <p>Background noise due to flow in wind tunnels contaminates desired data by decreasing the Signal-to-Noise Ratio. The use of Adaptive Noise Cancellation to remove background noise at measurement microphones is compromised when the reference sensor measures both background and desired noise. The technique proposed modifies the classical processing configuration based on the <span class="hlt">cross-correlation</span> between the reference and primary microphone. Background noise attenuation is achieved using a <span class="hlt">cross-correlation</span> sample width that encompasses only the background noise and a matched delay for the adaptive processing. A present limitation of the method is that a minimum time delay between the background noise and desired signal must exist in order for the correlated parts of the desired signal to be separated from the background noise in the crosscorrelation. A simulation yields primary signal recovery which can be predicted from the coherence of the background noise between the channels. Results are compared with two existing methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JaJAP..56a2701K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JaJAP..56a2701K"><span>High-dynamic-range <span class="hlt">cross-correlator</span> for shot-to-shot measurement of temporal contrast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kon, Akira; Nishiuchi, Mamiko; Kiriyama, Hiromitsu; Ogura, Koichi; Mori, Michiaki; Sakaki, Hironao; Kando, Masaki; Kondo, Kiminori</p> <p>2017-01-01</p> <p>The temporal contrast of an ultrahigh-intensity laser is a crucial parameter for laser plasma experiments. We have developed a multichannel <span class="hlt">cross-correlator</span> (MCCC) for single-shot measurements of the temporal contrast in a high-power laser system. The MCCC is based on third-order <span class="hlt">cross-correlation</span>, and has four channels and independent optical delay lines. We have experimentally demonstrated that the MCCC system achieves a high dynamic range of ˜1012 and a large temporal window of ˜1 ns. Moreover, we were able to measure the shot-to-shot fluctuations of a short-prepulse intensity at -26 ps and long-pulse (amplified spontaneous emission, ASE) intensities at -30, -450, and -950 ps before the arrival of the main pulse at the interaction point.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JSV...330.2910F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JSV...330.2910F"><span>New differential equations governing the response <span class="hlt">cross-correlations</span> of linear systems subjected to coloured loads</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Falsone, G.; Settineri, D.</p> <p>2011-06-01</p> <p>A procedure for evaluating the response <span class="hlt">cross-correlation</span> of a linear structural system subjected to the action of stationary random multi-correlated processes is presented in this work. It is based on the definition of the fourth-order differential equation governing the modal response <span class="hlt">cross-correlation</span> and of the corresponding solution. This is expressed in terms of the corresponding fundamental matrix, whose expression is related to the fundamental matrices of the differential equations governing the modal responses. The properties of this matrix allows to define a particular unconditionally stable numerical integration approach, which is composed of two independent step-by-step procedures, a progressive one and a regressive one. The applications have shown a level of accuracy comparable to that corresponding to the numerical solution of the double convolution integral, but the presented approach is characterised by a reduced computational effort.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=patent+AND+analysis&pg=6&id=EJ431570','ERIC'); return false;" href="https://eric.ed.gov/?q=patent+AND+analysis&pg=6&id=EJ431570"><span>Application and Effects of Linguistic <span class="hlt">Functions</span> on Information <span class="hlt">Retrieval</span> in a German Language Full-Text Database: Comparison between <span class="hlt">Retrieval</span> in Abstract and Full Text.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Tauchert, Wolfgang; And Others</p> <p>1991-01-01</p> <p>Describes the PADOK-II project in Germany, which was designed to give information on the effects of linguistic algorithms on <span class="hlt">retrieval</span> in a full-text database, the German Patent Information System (GPI). Relevance assessments are discussed, statistical evaluations are described, and searches are compared for the full-text section versus the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S51A2640X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S51A2640X"><span>Comparison of Source Time <span class="hlt">Functions</span> <span class="hlt">Retrieved</span> from Various Regional Waves and Coda Using Moderate Earthquakes in East and Central Asia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xie, J.; Torpey, M. E.</p> <p>2015-12-01</p> <p><span">Source time <span class="hlt">functions</span> may vary with various P and S wave types. Regional Lg waves have been used to estimate radiated energy and apparent stress. In nuclear explosion seismology, the practice of discriminating Earthquake and explosions using regional wave spectra and spectral ratios relies on a fundamental assumption that Earthquakes and explosions excite various regional waves in a systematically-different manner. We have been carrying out a systematic study to <span class="hlt">retrieve</span> source time <span class="hlt">functions</span> (STFs) from seismic sources using the empirical Green's <span class="hlt">function</span> (EGF) approach. In phase 1 of the study, we focus on <span class="hlt">retrieving</span> STFs from moderate earthquakes in east and central Asia using regional Lg, Pg, Lg coda, and Sn and Pn waves to see whether or not the shape of the STFs varies with the wave type. We explored various methods to reduce the noise in the deconvolved STFs which tend to be higher for the relatively weaker Pg, Sn, Pn and coda waves. For example, an array-stacking method is used to enhance source pulses and reduce the level of side-lobes. Preliminary results suggest that Lg and Lg coda STFs may be similar, as generally believed. Pg STF is less similar to Lg STF. For example, when a stacked Lg STF is clearly asymmetric with a sharp-rise time, the stack Pg STF seems to be fairly symmetric. In general, our confidence on this kind of dissimilarity is still limited by the non-diminishing deconvolution noise in the <span class="hlt">retrieved</span> Pg STFs, and by the small number of events studied. We are trying to further reduce the deconvolution noise for each regional wave, and find and analyze more moderate events. We will present newly-<span class="hlt">retrieved</span> STFs from each of the various regional waves and coda, and compare the pulse widths and shapes of the STFs from different waves. We will also present estimates of source-radiated energy and apparent stresses using the estimated Lg STFs without using various simplified source models and Q corrections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930042965&hterms=glacier+velocity&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dglacier%2Bvelocity','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930042965&hterms=glacier+velocity&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dglacier%2Bvelocity"><span>Application of image <span class="hlt">cross-correlation</span> to the measurement of glacier velocity using satellite image data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scambos, Theodore A.; Dutkiewicz, Melanie J.; Wison, Jeremy C.; Bindschadler, Robert A.</p> <p>1992-01-01</p> <p>A high-resolution map of the velocity field of the central portion of Ice Stream E in West Antarctica, generated by the displacement-measuring technique, is presented. The use of <span class="hlt">cross-correlation</span> software is found to be a significant improvement over previous manually based photogrammetric methods for velocity measurement, and is far more cost-effective than in situ methods in remote polar areas. A hue-intensity-saturation image of Ice Stream E and its velocity field is shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25474961','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25474961"><span>[Simulation of pseudo <span class="hlt">cross-correlation</span> degraded by the hyperspectral imaging of satellite complex motion].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Li-jun; Chang, Yue-e; Tang, Yi; Nan, Yi-bing; Guo, Qian</p> <p>2014-08-01</p> <p>The present paper proposed a spectral degradation theory based on the point spread matrix, which is developed from the simulation algorithm of degradation based on differential dynamic spectral imaging for moving imaging. According to the eight neighborhood mixing model, considering the varying movement with time of the satellite platform, the situation that different object pixel has different point spread matrix is corresponding to the concept of the pseudo <span class="hlt">cross-correlation</span> theory. Thus, the pseudo <span class="hlt">cross-correlation</span> degradation theory of moving spectral imaging is presented. In this method, the point spread matrix is constructed by the mean mixing ratio of eight neighborhoods, which can be calculated by the POS data on satellite using the differential imaging theory based on image motion matrix. When calculating the point spread matrix with the simulating POS data curve, we found out that the point spread matrix can be simplified according to the importance of mixing effect to reduce calculation. Then, the presentation and computing method of the pseudo <span class="hlt">cross-correlation</span> degradation theory of moving spectral imaging is clearly articulated, and the result of degradation simulating and calculating is evaluated qualitatively and quantitatively from imaging dimension and spectral dimension respectively, and the similarity between the degradation image and the initial image is revealed using the SSIM parameter. The pseudo <span class="hlt">cross-correlation</span> degradation theory of moving spectral imaging improves the existing problem of spectral imaging degradation based on the complex movement of satellite platform. The simulation results show that this kind of degradation theory is suitable for solving the problem of spectral imaging degradation based on the complex satellite platform movement completely.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.6451B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.6451B"><span>Global grid of master events for waveform <span class="hlt">cross-correlation</span>: from testing to real time processing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bobrov, Dmitry; Rozhkov, Mikhail; Kitov, Ivan</p> <p>2014-05-01</p> <p>Seismic monitoring of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) requires a globally uniform detection threshold, which is provided by geographical distribution of the Primary Seismic Network of the International Monitoring System (IMS). This detection threshold has to be as low as allowed by the entire set of real time and historical data recorded by the IMS. The International Data Centre (IDC) analyzes all relevant data in automatic processing and interactive review to issue a Reviewed Event Bulletin (REB), which includes all qualified events as obtained for the purpose of nuclear test monitoring. Since 2000, raw data, individual detections, and created events are saved in the IDC archive currently reaching tens of terabyte. In order to effectively use this archive in global monitoring we introduced the waveform <span class="hlt">cross</span> <span class="hlt">correlation</span> (matched filter) technique. <span class="hlt">Cross</span> <span class="hlt">correlation</span> between real time records at IMS stations and template waveforms is calculated for a dense (spacing of ~ 140 km) and regular grid of master events uniformly covering the globe. There are approximately 25,000 master events with 3 to 10 templates at IMS stations. In seismically active zones, we populate masters with real waveforms. For aseismic zones, we develop an extended set of synthetic templates for virtual master events. For optimal performance of <span class="hlt">cross</span> <span class="hlt">correlation</span>, the Principal and Independent Component Analysis are applied to the historical (from earthquakes and underground nuclear tests) and synthetic waveforms. Real waveform templates and selected PCA/ICA components are used in automatic processing for the production of a tentative <span class="hlt">cross-correlation</span> standard event list (XSEL).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DFDM32001T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DFDM32001T"><span>Wall parallel <span class="hlt">cross-correlations</span> of volumetric PTV measurements in a perturbed turbulent boundary layer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tan, Yan Ming; Longmire, Ellen</p> <p>2016-11-01</p> <p>A canonical turbulent boundary layer (Reτ = 2500) was perturbed by a narrowly spaced (0.2 δ) array of cylinders extending normal to the wall. Two array heights were considered, H = 0.2 δ and H = δ . Volumetric PTV measurements were acquired to understand 3-D variations in large scale structures within the log region of the unperturbed and perturbed flow. The recovery in the streamwise velocity coherence across the depth of the log region was analyzed using <span class="hlt">cross</span> <span class="hlt">correlations</span> between wall parallel planes. Conditional <span class="hlt">cross</span> <span class="hlt">correlations</span> are analyzed to examine the recovery in coherence specific to low momentum regions (LMRs), which can be signatures of vortex packets. The measurement volume was 0.70 δ (streamwise,x), 0.90 δ (spanwise,y), 0.12 δ (wall-normal,z). In the unperturbed flow, LMRs frequently extended through the entire depth (155 <=z+ <= 465). The <span class="hlt">cross</span> <span class="hlt">correlations</span> between planes at z+ = 155 and z+ = 465 exhibited strong skewness indicative of forward leaning structures. By comparison, downstream of the H = δ array, the wall normal extent of individual LMRs was frequently limited to the lower part of the measurement volume. The <span class="hlt">cross</span> <span class="hlt">correlation</span> magnitude and skewness remained suppressed relative to unperturbed flow up to 4.7 δ downstream. These observations suggest reduced coherence of LMRs and high momentum regions across the log region. This result was consistent with previous planar PIV measurements at z+ = 500 that showed hardly any long LMRs over distances up to 7 δ downstream of the H = δ array.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.459...21K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.459...21K"><span><span class="hlt">Cross-correlation</span> of gravitational lensing from DES Science Verification data with SPT and Planck lensing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kirk, D.; Omori, Y.; Benoit-Lévy, A.; Cawthon, R.; Chang, C.; Larsen, P.; Amara, A.; Bacon, D.; Crawford, T. M.; Dodelson, S.; Fosalba, P.; Giannantonio, T.; Holder, G.; Jain, B.; Kacprzak, T.; Lahav, O.; MacCrann, N.; Nicola, A.; Refregier, A.; Sheldon, E.; Story, K. T.; Troxel, M. A.; Vieira, J. D.; Vikram, V.; Zuntz, J.; Abbott, T. M. C.; Abdalla, F. B.; Becker, M. R.; Benson, B. A.; Bernstein, G. M.; Bernstein, R. A.; Bleem, L. E.; Bonnett, C.; Bridle, S. L.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carlstrom, J. E.; Rosell, A. Carnero; Kind, M. Carrasco; Carretero, J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Evrard, A. E.; Flaugher, B.; Frieman, J.; Gerdes, D. W.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Honscheid, K.; James, D. J.; Jarvis, M.; Kent, S.; Kuehn, K.; Kuropatkin, N.; Lima, M.; March, M.; Martini, P.; Melchior, P.; Miller, C. J.; Miquel, R.; Nichol, R. C.; Ogando, R.; Plazas, A. A.; Reichardt, C. L.; Roodman, A.; Rozo, E.; Rykoff, E. S.; Sako, M.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Simard, G.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Wechsler, R. H.; Weller, J.</p> <p>2016-06-01</p> <p>We measure the <span class="hlt">cross-correlation</span> between weak lensing of galaxy images and of the cosmic microwave background (CMB). The effects of gravitational lensing on different sources will be correlated if the lensing is caused by the same mass fluctuations. We use galaxy shape measurements from 139 deg2 of the Dark Energy Survey (DES) Science Verification data and overlapping CMB lensing from the South Pole Telescope (SPT) and Planck. The DES source galaxies have a median redshift of zmed ˜ 0.7, while the CMB lensing kernel is broad and peaks at z ˜ 2. The resulting <span class="hlt">cross-correlation</span> is maximally sensitive to mass fluctuations at z ˜ 0.44. Assuming the Planck 2015 best-fitting cosmology, the amplitude of the DES×SPT cross-power is found to be ASPT = 0.88 ± 0.30 and that from DES×Planck to be APlanck = 0.86 ± 0.39, where A = 1 corresponds to the theoretical prediction. These are consistent with the expected signal and correspond to significances of 2.9σ and 2.2σ, respectively. We demonstrate that our results are robust to a number of important systematic effects including the shear measurement method, estimator choice, photo-z uncertainty and CMB lensing systematics. We calculate a value of A = 1.08 ± 0.36 for DES×SPT when we correct the observations with a simple intrinsic alignment model. With three measurements of this <span class="hlt">cross-correlation</span> now existing in the literature, there is not yet reliable evidence for any deviation from the expected LCDM level of <span class="hlt">cross-correlation</span>. We provide forecasts for the expected signal-to-noise ratio of the combination of the five-year DES surve