Science.gov

Sample records for strongly delays pre-rrna

  1. The Strong Lensing Time Delay Challenge (2014)

    NASA Astrophysics Data System (ADS)

    Liao, Kai; Dobler, G.; Fassnacht, C. D.; Treu, T.; Marshall, P. J.; Rumbaugh, N.; Linder, E.; Hojjati, A.

    2014-01-01

    Time delays between multiple images in strong lensing systems are a powerful probe of cosmology. At the moment the application of this technique is limited by the number of lensed quasars with measured time delays. However, the number of such systems is expected to increase dramatically in the next few years. Hundred such systems are expected within this decade, while the Large Synoptic Survey Telescope (LSST) is expected to deliver of order 1000 time delays in the 2020 decade. In order to exploit this bounty of lenses we needed to make sure the time delay determination algorithms have sufficiently high precision and accuracy. As a first step to test current algorithms and identify potential areas for improvement we have started a "Time Delay Challenge" (TDC). An "evil" team has created realistic simulated light curves, to be analyzed blindly by "good" teams. The challenge is open to all interested parties. The initial challenge consists of two steps (TDC0 and TDC1). TDC0 consists of a small number of datasets to be used as a training template. The non-mandatory deadline is December 1 2013. The "good" teams that complete TDC0 will be given access to TDC1. TDC1 consists of thousands of lightcurves, a number sufficient to test precision and accuracy at the subpercent level, necessary for time-delay cosmography. The deadline for responding to TDC1 is July 1 2014. Submissions will be analyzed and compared in terms of predefined metrics to establish the goodness-of-fit, efficiency, precision and accuracy of current algorithms. This poster describes the challenge in detail and gives instructions for participation.

  2. Next generation strong lensing time delay estimation with Gaussian processes

    NASA Astrophysics Data System (ADS)

    Hojjati, Alireza; Linder, Eric V.

    2014-12-01

    Strong gravitational lensing forms multiple, time delayed images of cosmological sources, with the "focal length" of the lens serving as a cosmological distance probe. Robust estimation of the time delay distance can tightly constrain the Hubble constant as well as the matter density and dark energy. Current and next generation surveys will find hundreds to thousands of lensed systems but accurate time delay estimation from noisy, gappy light curves is potentially a limiting systematic. Using a large sample of blinded light curves from the Strong Lens Time Delay Challenge we develop and demonstrate a Gaussian process cross correlation technique that delivers an average bias within 0.1% depending on the sampling, necessary for subpercent Hubble constant determination. The fits are accurate (80% of them within one day) for delays from 5-100 days and robust against cadence variations shorter than six days. We study the effects of survey characteristics such as cadence, season, and campaign length, and derive requirements for time delay cosmology: in order not to bias the cosmology determination by 0.5 σ , the mean time delay fit accuracy must be better than 0.2%.

  3. STRONG LENS TIME DELAY CHALLENGE. I. EXPERIMENTAL DESIGN

    SciTech Connect

    Dobler, Gregory; Fassnacht, Christopher D.; Rumbaugh, Nicholas; Treu, Tommaso; Liao, Kai; Marshall, Phil; Hojjati, Alireza; Linder, Eric

    2015-02-01

    The time delays between point-like images in gravitational lens systems can be used to measure cosmological parameters. The number of lenses with measured time delays is growing rapidly; the upcoming Large Synoptic Survey Telescope (LSST) will monitor ∼10{sup 3} strongly lensed quasars. In an effort to assess the present capabilities of the community, to accurately measure the time delays, and to provide input to dedicated monitoring campaigns and future LSST cosmology feasibility studies, we have invited the community to take part in a ''Time Delay Challenge'' (TDC). The challenge is organized as a set of ''ladders'', each containing a group of simulated data sets to be analyzed blindly by participating teams. Each rung on a ladder consists of a set of realistic mock observed lensed quasar light curves, with the rungs' data sets increasing in complexity and realism. The initial challenge described here has two ladders, TDC0 and TDC1. TDC0 has a small number of data sets, and is designed to be used as a practice set by the participating teams. The (non-mandatory) deadline for completion of TDC0 was the TDC1 launch date, 2013 December 1. The TDC1 deadline was 2014 July 1. Here we give an overview of the challenge, we introduce a set of metrics that will be used to quantify the goodness of fit, efficiency, precision, and accuracy of the algorithms, and we present the results of TDC0. Thirteen teams participated in TDC0 using 47 different methods. Seven of those teams qualified for TDC1, which is described in the companion paper.

  4. STRONG LENS TIME DELAY CHALLENGE. II. RESULTS OF TDC1

    SciTech Connect

    Liao, Kai; Treu, Tommaso; Marshall, Phil; Fassnacht, Christopher D.; Rumbaugh, Nick; Dobler, Gregory; Aghamousa, Amir; Bonvin, Vivien; Courbin, Frederic; Meylan, Georges; Hojjati, Alireza; Jackson, Neal; Kashyap, Vinay; Mandel, Kaisey; Rathna Kumar, S.; Prabhu, Tushar P.; Linder, Eric; Meng, Xiao-Li; Moustakas, Leonidas A.; Romero-Wolf, Andrew [Jet Propulsion Laboratory, California Institute of Technology, M and others

    2015-02-10

    We present the results of the first strong lens time delay challenge. The motivation, experimental design, and entry level challenge are described in a companion paper. This paper presents the main challenge, TDC1, which consisted of analyzing thousands of simulated light curves blindly. The observational properties of the light curves cover the range in quality obtained for current targeted efforts (e.g., COSMOGRAIL) and expected from future synoptic surveys (e.g., LSST), and include simulated systematic errors. Seven teams participated in TDC1, submitting results from 78 different method variants. After describing each method, we compute and analyze basic statistics measuring accuracy (or bias) A, goodness of fit χ{sup 2}, precision P, and success rate f. For some methods we identify outliers as an important issue. Other methods show that outliers can be controlled via visual inspection or conservative quality control. Several methods are competitive, i.e., give |A| < 0.03, P < 0.03, and χ{sup 2} < 1.5, with some of the methods already reaching sub-percent accuracy. The fraction of light curves yielding a time delay measurement is typically in the range f = 20%-40%. It depends strongly on the quality of the data: COSMOGRAIL-quality cadence and light curve lengths yield significantly higher f than does sparser sampling. Taking the results of TDC1 at face value, we estimate that LSST should provide around 400 robust time-delay measurements, each with P < 0.03 and |A| < 0.01, comparable to current lens modeling uncertainties. In terms of observing strategies, we find that A and f depend mostly on season length, while P depends mostly on cadence and campaign duration.

  5. Strong Lens Time Delay Challenge. II. Results of TDC1

    NASA Astrophysics Data System (ADS)

    Liao, Kai; Treu, Tommaso; Marshall, Phil; Fassnacht, Christopher D.; Rumbaugh, Nick; Dobler, Gregory; Aghamousa, Amir; Bonvin, Vivien; Courbin, Frederic; Hojjati, Alireza; Jackson, Neal; Kashyap, Vinay; Rathna Kumar, S.; Linder, Eric; Mandel, Kaisey; Meng, Xiao-Li; Meylan, Georges; Moustakas, Leonidas A.; Prabhu, Tushar P.; Romero-Wolf, Andrew; Shafieloo, Arman; Siemiginowska, Aneta; Stalin, Chelliah S.; Tak, Hyungsuk; Tewes, Malte; van Dyk, David

    2015-02-01

    We present the results of the first strong lens time delay challenge. The motivation, experimental design, and entry level challenge are described in a companion paper. This paper presents the main challenge, TDC1, which consisted of analyzing thousands of simulated light curves blindly. The observational properties of the light curves cover the range in quality obtained for current targeted efforts (e.g., COSMOGRAIL) and expected from future synoptic surveys (e.g., LSST), and include simulated systematic errors. Seven teams participated in TDC1, submitting results from 78 different method variants. After describing each method, we compute and analyze basic statistics measuring accuracy (or bias) A, goodness of fit χ2, precision P, and success rate f. For some methods we identify outliers as an important issue. Other methods show that outliers can be controlled via visual inspection or conservative quality control. Several methods are competitive, i.e., give |A| < 0.03, P < 0.03, and χ2 < 1.5, with some of the methods already reaching sub-percent accuracy. The fraction of light curves yielding a time delay measurement is typically in the range f = 20%-40%. It depends strongly on the quality of the data: COSMOGRAIL-quality cadence and light curve lengths yield significantly higher f than does sparser sampling. Taking the results of TDC1 at face value, we estimate that LSST should provide around 400 robust time-delay measurements, each with P < 0.03 and |A| < 0.01, comparable to current lens modeling uncertainties. In terms of observing strategies, we find that A and f depend mostly on season length, while P depends mostly on cadence and campaign duration.

  6. Dynamics of strongly coupled spatially distributed logistic equations with delay

    NASA Astrophysics Data System (ADS)

    Kashchenko, I. S.; Kashchenko, S. A.

    2015-04-01

    The dynamics of a system of two logistic delay equations with spatially distributed coupling is studied. The coupling coefficient is assumed to be sufficiently large. Special nonlinear systems of parabolic equations are constructed such that the behavior of their solutions is determined in the first approximation by the dynamical properties of the original system.

  7. Strong gravitational field time delay for photons coupled to Weyl tensor in a Schwarzschild black hole

    NASA Astrophysics Data System (ADS)

    Lu, Xu; Yang, Feng-Wei; Xie, Yi

    2016-07-01

    We analyze strong gravitational field time delay for photons coupled to the Weyl tensor in a Schwarzschild black hole. By making use of the method of strong deflection limit, we find that these time delays between relativistic images are significantly affected by polarization directions of such a coupling. A practical problem about determination of the polarization direction by observations is investigated. It is found that if the first and second relativistic images can be resolved, the measurement of time delay can more effectively improve detectability of the polarization direction.

  8. The transition between strong and weak chaos in delay systems: Stochastic modeling approach.

    PubMed

    Jüngling, Thomas; D'Huys, Otti; Kinzel, Wolfgang

    2015-06-01

    We investigate the scaling behavior of the maximal Lyapunov exponent in chaotic systems with time delay. In the large-delay limit, it is known that one can distinguish between strong and weak chaos depending on the delay scaling, analogously to strong and weak instabilities for steady states and periodic orbits. Here we show that the Lyapunov exponent of chaotic systems shows significant differences in its scaling behavior compared to constant or periodic dynamics due to fluctuations in the linearized equations of motion. We reproduce the chaotic scaling properties with a linear delay system with multiplicative noise. We further derive analytic limit cases for the stochastic model illustrating the mechanisms of the emerging scaling laws. PMID:26172783

  9. The transition between strong and weak chaos in delay systems: Stochastic modeling approach

    NASA Astrophysics Data System (ADS)

    Jüngling, Thomas; D'Huys, Otti; Kinzel, Wolfgang

    2015-06-01

    We investigate the scaling behavior of the maximal Lyapunov exponent in chaotic systems with time delay. In the large-delay limit, it is known that one can distinguish between strong and weak chaos depending on the delay scaling, analogously to strong and weak instabilities for steady states and periodic orbits. Here we show that the Lyapunov exponent of chaotic systems shows significant differences in its scaling behavior compared to constant or periodic dynamics due to fluctuations in the linearized equations of motion. We reproduce the chaotic scaling properties with a linear delay system with multiplicative noise. We further derive analytic limit cases for the stochastic model illustrating the mechanisms of the emerging scaling laws.

  10. Attractor minimal sets for cooperative and strongly convex delay differential systems

    NASA Astrophysics Data System (ADS)

    Novo, Sylvia; Obaya, Rafael; Sanz, Ana M.

    We study the skew-product semiflow induced by a family of convex and cooperative delay differential systems. Under some monotonicity assumptions, we obtain an ergodic representation for the upper Lyapunov exponent of a minimal subset. In addition, when eventually strong convexity at one point is assumed and there exist two completely strongly ordered minimal subsets K1≪ CK2, we show that K1 is an attractor subset which is a copy of the base. The long-time behaviour of every trajectory strongly ordered with K2 is then deduced. Some examples of application of the theory are shown.

  11. Strongly Lensed Jets, Time Delays, and the Value of H 0

    NASA Astrophysics Data System (ADS)

    Barnacka, Anna; Geller, Margaret J.; Dell'Antonio, Ian P.; Benbow, Wystan

    2015-01-01

    In principle, the most straightforward method of estimating the Hubble constant relies on time delays between mirage images of strongly lensed sources. It is a puzzle, then, that the values of H 0 obtained with this method span a range from ~50-100 km s-1Mpc-1. Quasars monitored to measure these time delays are multi-component objects. The variability may arise from different components of the quasar or may even originate from a jet. Misidentifying a variable-emitting region in a jet with emission from the core region may introduce an error in the Hubble constant derived from a time delay. Here, we investigate the complex structure of the sources as the underlying physical explanation of the wide spread in values of the Hubble constant based on gravitational lensing. Our Monte Carlo simulations demonstrate that the derived value of the Hubble constant is very sensitive to the offset between the center of the emission and the center of the variable emitting region. Therefore, we propose using the value of H 0 known from other techniques to spatially resolve the origin of the variable emission once the time delay is measured. We particularly advocate this method for gamma-ray astronomy, where the angular resolution of detectors reaches approximately 0.°1 lensed blazars offer the only route for identify the origin of gamma-ray flares. Large future samples of gravitationally lensed sources identified with Euclid, SKA, and LSST will enable a statistical determination of H 0.

  12. Group delay spread analysis of strongly coupled 3-core fibers: an effect of bending and twisting.

    PubMed

    Fujisawa, Takeshi; Saitoh, Kunimasa

    2016-05-01

    The effect of bending and twisting on the group delay spread (GDS) of strongly coupled 3-core fibers is investigated. For the random perturbation inducing modal coupling in the fiber, two physical mechanisms, microbending or macrobending with random twist, are considered. Calculated results show that both mechanisms lead to the same effect, namely, reduced GDS under strong coupling regime. Furthermore, a novel fiber structure having an air-hole at the center is proposed for reducing the GDS. By placing the air-hole, the effective index difference between fundamental and the higher order modes is reduced, leading to strong modal mixing in the fiber, and hence, small GDS. Calculated GDS of the fiber with air-hole is almost 1/5 compared with that of the fiber without air-hole. PMID:27137571

  13. STRONGLY LENSED JETS, TIME DELAYS, AND THE VALUE OF H {sub 0}

    SciTech Connect

    Barnacka, Anna; Geller, Margaret J.; Benbow, Wystan; Dell'Antonio, Ian P.

    2015-01-20

    In principle, the most straightforward method of estimating the Hubble constant relies on time delays between mirage images of strongly lensed sources. It is a puzzle, then, that the values of H {sub 0} obtained with this method span a range from ∼50-100 km s{sup –1}Mpc{sup –1}. Quasars monitored to measure these time delays are multi-component objects. The variability may arise from different components of the quasar or may even originate from a jet. Misidentifying a variable-emitting region in a jet with emission from the core region may introduce an error in the Hubble constant derived from a time delay. Here, we investigate the complex structure of the sources as the underlying physical explanation of the wide spread in values of the Hubble constant based on gravitational lensing. Our Monte Carlo simulations demonstrate that the derived value of the Hubble constant is very sensitive to the offset between the center of the emission and the center of the variable emitting region. Therefore, we propose using the value of H {sub 0} known from other techniques to spatially resolve the origin of the variable emission once the time delay is measured. We particularly advocate this method for gamma-ray astronomy, where the angular resolution of detectors reaches approximately 0.°1; lensed blazars offer the only route for identify the origin of gamma-ray flares. Large future samples of gravitationally lensed sources identified with Euclid, SKA, and LSST will enable a statistical determination of H {sub 0}.

  14. Fast and Reliable Time Delay Estimation of Strong Lens Systems Using the Smoothing and Cross-correlation Methods

    NASA Astrophysics Data System (ADS)

    Aghamousa, Amir; Shafieloo, Arman

    2015-05-01

    The observable time delays between multiple images of strong lensing systems with time variable sources can provide us with some valuable information for probing the expansion history of the universe. Estimating these time delays can be very challenging due to complexities in the observed data caused by seasonal gaps, various noises, and systematics such as unknown microlensing effects. In this paper, we introduce a novel approach for estimating the time delays for strong lensing systems, implementing various statistical methods of data analysis including the smoothing and cross-correlation methods. The method we introduce in this paper has recently been used in the TDC0 and TDC1 Strong Lens Time Delay Challenges and has shown its power in providing reliable and precise estimates of time delays dealing with data with different complexities.

  15. Polarisation response of delay dependent absorption modulation in strong field dressed helium atoms probed near threshold

    NASA Astrophysics Data System (ADS)

    Simpson, E. R.; Sanchez-Gonzalez, A.; Austin, D. R.; Diveki, Z.; Hutchinson, S. E. E.; Siegel, T.; Ruberti, M.; Averbukh, V.; Miseikis, L.; Strüber, C. S.; Chipperfield, L.; Marangos, J. P.

    2016-08-01

    We present the first measurement of the vectorial response of strongly dressed helium atoms probed by an attosecond pulse train (APT) polarised either parallel or perpendicular to the dressing field polarisation. The transient absorption is probed as a function of delay between the APT and the linearly polarised 800 nm field of peak intensity 1.3× {10}14 {{W}} {{cm}}-2. The APT spans the photon energy range 16–42 eV, covering the first ionisation energy of helium (24.59 eV). With parallel polarised dressing and probing fields, we observe modulations with periods of one half and one quarter of the dressing field period. When the polarisation of the dressing field is altered from parallel to perpendicular with respect to the APT polarisation we observe a large suppression in the modulation depth of the above ionisation threshold absorption. In addition to this we present the intensity dependence of the harmonic modulation depth as a function of delay between the dressing and probe fields, with dressing field peak intensities ranging from 2 × 1012 to 2 × 1014 {{W}} {{cm}}-2. We compare our experimental results with a full-dimensional solution of the single-atom time-dependent (TD) Schrödinger equation obtained using the recently developed abinitio TD B-spline ADC method and find good qualitative agreement for the above threshold harmonics.

  16. TWO ACCURATE TIME-DELAY DISTANCES FROM STRONG LENSING: IMPLICATIONS FOR COSMOLOGY

    SciTech Connect

    Suyu, S. H.; Treu, T.; Auger, M. W.; Hilbert, S.; Blandford, R. D.; Marshall, P. J.; Tewes, M.; Courbin, F.; Meylan, G.; Fassnacht, C. D.; Koopmans, L. V. E.; Sluse, D.

    2013-04-01

    Strong gravitational lenses with measured time delays between the multiple images and models of the lens mass distribution allow a one-step determination of the time-delay distance, and thus a measure of cosmological parameters. We present a blind analysis of the gravitational lens RXJ1131-1231 incorporating (1) the newly measured time delays from COSMOGRAIL, the COSmological MOnitoring of GRAvItational Lenses, (2) archival Hubble Space Telescope imaging of the lens system, (3) a new velocity-dispersion measurement of the lens galaxy of 323 {+-} 20 km s{sup -1} based on Keck spectroscopy, and (4) a characterization of the line-of-sight structures via observations of the lens' environment and ray tracing through the Millennium Simulation. Our blind analysis is designed to prevent experimenter bias. The joint analysis of the data sets allows a time-delay distance measurement to 6% precision that takes into account all known systematic uncertainties. In combination with the Wilkinson Microwave Anisotropy Probe seven-year (WMAP7) data set in flat wCDM cosmology, our unblinded cosmological constraints for RXJ1131-1231 are H{sub 0}=80.0{sup +5.8}{sub -5.7} km s{sup -1} Mpc{sup -1}, {Omega}{sub de} = 0.79 {+-} 0.03, and w=-1.25{sup +0.17}{sub -0.21}. We find the results to be statistically consistent with those from the analysis of the gravitational lens B1608+656, permitting us to combine the inferences from these two lenses. The joint constraints from the two lenses and WMAP7 are H{sub 0}=75.2{sup +4.4}{sub -4.2} km s{sup -1} Mpc{sup -1}, {Omega}{sub de}=0.76{sup +0.02}{sub -0.03}, and w = -1.14{sup +0.17}{sub -0.20} in flat wCDM, and H{sub 0}=73.1{sup +2.4}{sub -3.6} km s{sup -1} Mpc{sup -1}, {Omega}{sub {Lambda}}=0.75{sup +0.01}{sub -0.02}, and {Omega}{sub k}=0.003{sup +0.005}{sub -0.006} in open {Lambda}CDM. Time-delay lenses constrain especially tightly the Hubble constant H{sub 0} (5.7% and 4.0% respectively in wCDM and open {Lambda}CDM) and curvature of the

  17. Attosecond time delays in the nuclear dynamics of strong-field molecular dissociation

    NASA Astrophysics Data System (ADS)

    Armstrong, Greg; Ultrafast Molecular Physics Group Collaboration

    2016-05-01

    The relative time delay in the photoemission from neighboring atomic valence sub-shells has become an area of considerable recent interest, with delays of tens of attoseconds reported in pump-probe experiments for a number of atomic targets. Such delays may be extracted, for example, from phase differences in the photoelectron energy spectra for the different sub-shells as a function of delay between pump and probe pulses. The focus of such experiments has, to date, been atomic targets, on the assumption that only electronic motion can lead to delays on the attosecond scale.We investigate the molecular analogue of such studies by calculating the kinetic-energy release (KER) spectrum for neighboring vibrational states as a function of pump-probe delay time. In particular, we focus on molecular targets where electronic excitation is negligible, and show that attosecond time delays are also possible for purely nuclear motion. We will present evidence of these attosecond delays derived from both numerical solutions of the time-dependent Schrödinger equation and experiment. We analyze and understand the observed shifts using the photon-phase formalism. G.S.J. Armstrong, J. McKenna, B. Gaire, M. Zohrabi, B. Berry, B. Jochim, Kanaka Raju, P., P. Feizollah, K.D. Carnes, Ben-Itzhak, B.D. Esry.

  18. Control of Stimulated Raman Scattering in the Strongly Nonlinear and Kinetic Regime Using Spike Trains of Uneven Duration and Delay

    NASA Astrophysics Data System (ADS)

    Albright, B. J.; Yin, L.; Afeyan, B.

    2014-07-01

    Stimulated Raman scattering (SRS) in its strongly nonlinear, kinetic regime is controlled by a technique of deterministic, strong temporal modulation and spatial scrambling of laser speckle patterns, called spike trains of uneven duration and delay (STUD) pulses [B. Afeyan and S. Hüller (unpublished)]. Kinetic simulations show that the proper use of STUD pulses decreases SRS reflectivity by more than an order of magnitude over random-phase-plate or induced-spatial-incoherence beams of the same average intensity and comparable bandwidth.

  19. The mass-sheet degeneracy and time-delay cosmography: analysis of the strong lens RXJ1131-1231

    NASA Astrophysics Data System (ADS)

    Birrer, Simon; Amara, Adam; Refregier, Alexandre

    2016-08-01

    We present extended modelling of the strong lens system RXJ1131-1231 with archival data in two HST bands in combination with existing line-of-sight contribution and velocity dispersion estimates. Our focus is on source size and its influence on time-delay cosmography. We therefore examine the impact of mass-sheet degeneracy and especially the degeneracy pointed out by Schneider & Sluse (2013) [1] using the source reconstruction scale. We also extend on previous work by further exploring the effects of priors on the kinematics of the lens and the external convergence in the environment of the lensing system. Our results coming from RXJ1131-1231 are given in a simple analytic form so that they can be easily combined with constraints coming from other cosmological probes. We find that the choice of priors on lens model parameters and source size are subdominant for the statistical errors for H0 measurements of this systems. The choice of prior for the source is sub-dominant at present (2% uncertainty on H0) but may be relevant for future studies. More importantly, we find that the priors on the kinematic anisotropy of the lens galaxy have a significant impact on our cosmological inference. When incorporating all the above modeling uncertainties, we find H0 = 86.6+6.8‑6.9 km s‑1 Mpc‑1, when using kinematic priors similar to other studies. When we use a different kinematic prior motivated by Barnabè et al. (2012) [2] but covering the same anisotropic range, we find H0 = 74.5+8.0‑7.8 km s‑1 Mpc‑1. This means that the choice of kinematic modeling and priors have a significant impact on cosmographic inferences. The way forward is either to get better velocity dispersion measures which would down weight the impact of the priors or to construct physically motivated priors for the velocity dispersion model.

  20. Effect of delayed link failure on probability of loss of assured safety in temperature-dependent systems with multiple weak and strong links.

    SciTech Connect

    Johnson, J. D.; Oberkampf, William Louis; Helton, Jon Craig

    2007-05-01

    Weak link (WL)/strong link (SL) systems constitute important parts of the overall operational design of high consequence systems, with the SL system designed to permit operation of the system only under intended conditions and the WL system designed to prevent the unintended operation of the system under accident conditions. Degradation of the system under accident conditions into a state in which the WLs have not deactivated the system and the SLs have failed in the sense that they are in a configuration that could permit operation of the system is referred to as loss of assured safety. The probability of such degradation conditional on a specific set of accident conditions is referred to as probability of loss of assured safety (PLOAS). Previous work has developed computational procedures for the calculation of PLOAS under fire conditions for a system involving multiple WLs and SLs and with the assumption that a link fails instantly when it reaches its failure temperature. Extensions of these procedures are obtained for systems in which there is a temperature-dependent delay between the time at which a link reaches its failure temperature and the time at which that link actually fails.

  1. HIV-1 epitope-specific CD8+ T cell responses strongly associated with delayed disease progression cross-recognize epitope variants efficiently.

    PubMed

    Turnbull, Emma L; Lopes, A Ross; Jones, Nicola A; Cornforth, David; Newton, Phillipa; Aldam, Diana; Pellegrino, Pierre; Turner, Jo; Williams, Ian; Wilson, Craig M; Goepfert, Paul A; Maini, Mala K; Borrow, Persephone

    2006-05-15

    The ability of HIV-1-specific CD8(+) T cell responses to recognize epitope variants resulting from viral sequence variation in vivo may affect the ease with which HIV-1 can escape T cell control and impact on the rate of disease progression in HIV-1-infected humans. Here, we studied the functional cross-reactivity of CD8 responses to HIV-1 epitopes restricted by HLA class I alleles associated with differential prognosis of infection. We show that the epitope-specific responses exhibiting the most efficient cross-recognition of amino acid-substituted variants were those strongly associated with delayed progression to disease. Not all epitopes restricted by the same HLA class I allele showed similar variant cross-recognition efficiency, consistent with the hypothesis that the reported associations between particular HLA class I alleles and rate of disease progression may be due to the quality of responses to certain "critical" epitopes. Irrespective of their efficiency of functional cross-recognition, CD8(+) T cells of all HIV-1 epitope specificities examined showed focused TCR usage. Furthermore, interpatient variability in variant cross-reactivity correlated well with use of different dominant TCR Vbeta families, suggesting that flexibility is not conferred by the overall clonal breadth of the response but instead by properties of the dominant TCR(s) used for epitope recognition. A better understanding of the features of T cell responses associated with long-term control of viral replication should facilitate rational vaccine design. PMID:16670322

  2. Equivalent Stimuli Are More Strongly Related after Training with Delayed Matching than after Simultaneous Matching: A Study Using the Implicit Relational Assessment Procedure (IRAP)

    ERIC Educational Resources Information Center

    Bortoloti, Renato; de Rose, Julio C.

    2012-01-01

    Bortoloti and de Rose (2009) found evidence that the level of functional transfer is higher in equivalence classes generated by delayed matching to sample (DMTS) than in classes generated by simultaneous matching (SMTS). We attempted to replicate these findings with the Implicit Relational Assessment Procedure (IRAP). Two experimental groups…

  3. A strongly greenish-blue-emitting Cu4Cl4 cluster with an efficient spin-orbit coupling (SOC): fast phosphorescence versus thermally activated delayed fluorescence.

    PubMed

    Chen, Xu-Lin; Yu, Rongmin; Wu, Xiao-Yuan; Liang, Dong; Jia, Ji-Hui; Lu, Can-Zhong

    2016-05-01

    In this communication, we report a new greenish-blue-emitting Cu(i) complex, Cu4Cl4(NP)2, a with high photoluminescence quantum yield of 90% and a short decay time of 9.9 μs. Due to the strong SOC combined with the small activation energy ΔEST, the emission at room temperature consists of approximately equivalent fast phosphorescence and TADF. PMID:27086679

  4. Delayed ejaculation

    MedlinePlus

    Ejaculatory incompetence; Sex - delayed ejaculation; Retarded ejaculation; Anejaculation; Infertility - delayed ejaculation ... include: Religious background that makes the person view sex as sinful Lack of attraction for a partner ...

  5. Delayed ejaculation

    MedlinePlus

    Ejaculatory incompetence; Sex - delayed ejaculation; Retarded ejaculation; Anejaculation ... include: Religious background that makes the person view sex as sinful Lack of attraction for a partner ...

  6. Delayed discharge.

    PubMed

    Allen, Daniel

    2016-07-01

    Essential facts Delays in discharging older peo ple from hospital cost the NHS £820 million a year, according to a report from the National Audit Office (NAO). Last year in acute hospitals, 1.15 million bed days were lost to delayed transfers of care, an increase of 31% since 2013. The NAO says rising demand for NHS services is compounded by reduced local authority spending on adult social care - down by 10% since 2009-10. PMID:27380673

  7. Developmental delay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrition support is essential for the care of the child with developmental delay. After a thorough evaluation, an individualized intervention plan that accounts for the child’s nutrition status, feeding ability, and medical condition may be determined. Nutrition assessments may be performed at leas...

  8. Strong Interaction

    SciTech Connect

    Karsch, F.; Vogelsang, V.

    2009-09-29

    We will give here an overview of our theory of the strong interactions, Quantum Chromo Dynamics (QCD) and its properties. We will also briefly review the history of the study of the strong interactions, and the discoveries that ultimately led to the formulation of QCD. The strong force is one of the four known fundamental forces in nature, the others being the electromagnetic, the weak and the gravitational force. The strong force, usually referred to by scientists as the 'strong interaction', is relevant at the subatomic level, where it is responsible for the binding of protons and neutrons to atomic nuclei. To do this, it must overcome the electric repulsion between the protons in an atomic nucleus and be the most powerful force over distances of a few fm (1fm=1 femtometer=1 fermi=10{sup -15}m), the typical size of a nucleus. This property gave the strong force its name.

  9. Time delay in molecular photoionization

    NASA Astrophysics Data System (ADS)

    Hockett, P.; Frumker, E.; Villeneuve, D. M.; Corkum, P. B.

    2016-05-01

    Time-delays in the photoionization of molecules are investigated. As compared to atomic ionization, the time-delays expected from molecular ionization present a much richer phenomenon, with a strong spatial dependence due to the anisotropic nature of the molecular scattering potential. We investigate this from a scattering theory perspective, and make use of molecular photoionization calculations to examine this effect in representative homonuclear and hetronuclear diatomic molecules, nitrogen and carbon monoxide. We present energy and angle-resolved maps of the Wigner delay time for single-photon valence ionization, and discuss the possibilities for experimental measurements.

  10. Delaying obsolescence.

    PubMed

    Lawlor, Rob

    2015-04-01

    This paper argues that those who emphasise that designers and engineers need to plan for obsolescence are too conservative. Rather, in addition to planning for obsolescence, designers and engineers should also think carefully about what they could do in order delay obsolescence. They should so this by thinking about the design itself, thinking of ways in which products could be useful and appealing for longer before becoming obsolete, as well thinking about the wider context in terms of the marketing of products, and also the social and legal. The paper also considers objections that these suggestions are unrealistically idealistic, failing to recognise the economic realities. I respond to these objections appealing to research in advertising, psychology, cognitive linguistics, philosophy, history, and economics, as well as drawing on the Statement of Ethical Principles developed by the Royal Academy of Engineering and the Engineering Council. PMID:24792878

  11. On Strong Anticipation

    PubMed Central

    Stepp, N.; Turvey, M. T.

    2009-01-01

    We examine Dubois's (2003) distinction between weak anticipation and strong anticipation. Anticipation is weak if it arises from a model of the system via internal simulations. Anticipation is strong if it arises from the system itself via lawful regularities embedded in the system's ordinary mode of functioning. The assumption of weak anticipation dominates cognitive science and neuroscience and in particular the study of perception and action. The assumption of strong anticipation, however, seems to be required by anticipation's ubiquity. It is, for example, characteristic of homeostatic processes at the level of the organism, organs, and cells. We develop the formal distinction between strong and weak anticipation by elaboration of anticipating synchronization, a phenomenon arising from time delays in appropriately coupled dynamical systems. The elaboration is conducted in respect to (a) strictly physical systems, (b) the defining features of circadian rhythms, often viewed as paradigmatic of biological behavior based in internal models, (c) Pavlovian learning, and (d) forward models in motor control. We identify the common thread of strongly anticipatory systems and argue for its significance in furthering understanding of notions such as “internal”, “model” and “prediction”. PMID:20191086

  12. Ionospheric irregularity influences on GPS time delay

    NASA Astrophysics Data System (ADS)

    Mansoori, Azad Ahmad; Gwal, Ashok Kumar; Khan, Parvaiz A.; Bhawre, Purushottam

    All the trans-ionospheric signals interact with the ionosphere during their passage through ionosphere, hence are strongly influenced by the ionosphere. One of most important ionospheric effects on the trans-ionospheric signals is the delay both in range and time. Under this investigation we have studied the variability of ionospheric range delay in GPS signals. To accomplish this study we have used the GPS measurements at a low latitude station, IISC Bangalore (13.02N, 77.57E) during January 2012 to December 2012. We studied the diurnal monthly as well as seasonal variability of the range delay. We also selected five intense geomagnetic storms that occurred during 2012 and investigated the variability of delay during the disturbed conditions. From our study we found the diurnal variability of the range delay is similar to the diurnal pattern observed for TEC. The delay is maximum during the month of October while lowest delay is found to occur in the month of December. During summer season the range delay in GPS signals in less while the largest delay occurs during the equinox season. The variability of delay during the geomagnetic storms of 09 Mar. 2012, 24 Apr. 2012, 15 Jul. 2012, 01 Oct. 2012 and 14 Nov. 2012 were also studied. All these geomagnetic storms belonged to intense category. We found that the value of delay is strongly increased during the course of geomagnetic storms. We took the peak value of delay as well as calculated the enhancement in the delay during these geomagnetic storms and then investigated their correlation with the storm intensity index Dst. Both the delays follow a very good correlation with Dst index.

  13. Early identification of motor delay

    PubMed Central

    Harris, Susan R.

    2016-01-01

    Objective To describe the Harris Infant Neuromotor Test (HINT), an infant neuromotor test using Canadian norms published in 2010 that could be used to screen for motor delay during the first year of life. Quality of evidence Extensive research has been published on the intrarater, interrater, and test-retest reliability and the content, concurrent, predictive, and known-groups validity of the HINT, as well as on the sensitivity, specificity, and positive and negative predictive values of parental concerns, as assessed by the HINT. Most evidence is level II. Main message Diagnosing motor delays during the first year of life is important because these often indicate more generalized developmental delays or specific disabilities, such as cerebral palsy. Parental concerns about their children’s motor development are strongly predictive of subsequent diagnoses involving motor delay. Conclusion Only through early identification of developmental motor delays, initially with screening tools such as the HINT, is it possible to provide referrals for early intervention that could benefit both the infant and the family. PMID:27521388

  14. Relativistic calculations of angle-dependent photoemission time delay

    NASA Astrophysics Data System (ADS)

    Kheifets, Anatoli; Mandal, Ankur; Deshmukh, Pranawa C.; Dolmatov, Valeriy K.; Keating, David A.; Manson, Steven T.

    2016-07-01

    Angular dependence of photoemission time delay for the valence n p3 /2 and n p1 /2 subshells of Ar, Kr, and Xe is studied in the dipole relativistic random phase approximation. Strong angular anisotropy of the time delay is reproduced near respective Cooper minima while the spin-orbit splitting affects the time delay near threshold.

  15. Delayed orgasm and anorgasmia.

    PubMed

    Jenkins, Lawrence C; Mulhall, John P

    2015-11-01

    Delayed orgasm/anorgasmia defined as the persistent or recurrent difficulty, delay in, or absence of attaining orgasm after sufficient sexual stimulation, which causes personal distress. Delayed orgasm and anorgasmia are associated with significant sexual dissatisfaction. A focused medical history can shed light on the potential etiologies, which include medications, penile sensation loss, endocrinopathies, penile hyperstimulation, and psychological etiologies. Unfortunately, there are no excellent pharmacotherapies for delayed orgasm/anorgasmia, and treatment revolves largely around addressing potential causative factors and psychotherapy. PMID:26439762

  16. Speech and Language Delay

    MedlinePlus

    MENU Return to Web version Speech and Language Delay Overview How do I know if my child has speech delay? Every child develops at his or her ... of the same age, the problem may be speech delay. Your doctor may think your child has ...

  17. Delay Discounting and Gambling

    PubMed Central

    Madden, Gregory J.; Francisco, Monica T.; Brewer, Adam T.; Stein, Jeffrey S.

    2011-01-01

    Delay discounting describes the decline in the value of a reinforcer as the delay to that reinforcer increases. A review of the available studies revealed that steep delay discounting is positively correlated with problem or pathological gambling. One hypothesis regarding this correlation derives from the discounting equation proposed by Mazur (1989). According to the equation, steeper discounting renders the difference between fixed-delayed rewards and gambling-like variable-delayed rewards larger; with the latter being more valuable. The present study was designed to test this prediction by first assessing rats’ impulsive choices across four delays to a larger-later reinforcer. A second condition quantified strength of preference for mixed- over fixed-delays, with the duration of the latter adjusted between sessions to achieve indifference. Strength of preference for the mixed-delay alternative is given by the fixed delay at indifference (lower fixed-delay values reflect stronger preferences). Percent impulsive choice was not correlated with the value of the fixed delay at indifference and, therefore, the prediction of the hyperbolic model of gambling was not supported. A follow-up assessment revealed a significant decrease in impulsive choice after the second condition. This shift in impulsive choice could underlie the failure to observe the predicted correlation between impulsive choice and degree of preference for mixed- over fixed delays. PMID:21352902

  18. Delayed Geodynamo in Hadean

    NASA Astrophysics Data System (ADS)

    Arkani-Hamed, J.

    2014-12-01

    Paleointensity measurements of Archean rocks reveal a strong geodynamo at ~3.45 Ga, while excess nitrogen content of lunar soil samples implies no geodynamo at ~3.9 Ga. Here I propose that initiation of a strong geodynamo is delayed due to accretion style of Earth, involving collision and merging of a few dozen Moon to Mars size planetary embryos. Two accretion scenarios consisting of 25 and 50 embryos are investigated. The collision of an embryo heats the proto-Earth's core differentially and the rotating low-viscosity core stably stratifies, creating a spherically symmetric and radially increasing temperature distribution. Convection starts in the outer core after each impact but is destroyed by the next impact. The iron core of an impacting embryo descends in the mantle and merges to the proto-Earth's core. Both adiabatic and non-adiabatic merging cases are studied. A major part of the gravitational energy released due to core merging is used to lift up the upper portion of the core to emplace the impactor core material at the neutrally buoyant level in the proto-Earth's core. The remaining energy is converted to heat. In the adiabatic case the merging embryo's core retains all of the remaining energy, while in the non-adiabatic merging 50% of the remaining energy is shared with the outer part of the proto-Earth's core where the embryo's core descends. The two merging models result in significantly different temperature distributions in the core at the end of accretion. After the accretion, the convecting shell in the outer core grows monotonically and generates geodynamo gradually. It takes about 50-100 Myr for the convecting shell to generate a strong dipole field at the surface, 50,000 to 100,000 nT, in the presence of a large stably stratified liquid inner core when the convecting outer core thickness exceeds about one half the radius of the Earth's core.

  19. Angular dependence of Wigner time delay: Relativistic Effects

    NASA Astrophysics Data System (ADS)

    Mandal, A.; Deshmukh, P. C.; Manson, S. T.; Kkeifets, A. S.

    2016-05-01

    Laser assisted photoionization time delay mainly consists of two parts: Wigner time delay, and time delay in continuum-continuum transition. Wigner time delay results from the energy derivative of the phase of the photoionization amplitude (matrix element). In general, the photoionization time delay is not the same in all directions relative to the incident photon polarization, although when a single transition dominates the amplitude, the resultant time delay is essentially isotropic. The relativistic-random-phase approximation is employed to determine the Wigner time delay in photoionization from the outer np subshells of the noble gas atoms, Ne through Xe. The time delay is found to significantly depend on angle, as well as energy. The angular dependence of the time delay is found to be quite sensitive to atomic dynamics and relativistic effects, and exhibit strong energy and angular variation in the neighborhood of Cooper minima. Work supported by DOE, Office of Chemical Sciences and DST (India).

  20. Strong Bragg backscattering in reflectometry

    NASA Astrophysics Data System (ADS)

    Gusakov, E. Z.; Heuraux, S.; Popov, A. Yu

    2009-06-01

    The reflection of the probing microwave occurring in the vicinity of the backscattering Bragg resonance point (far from the cut-off) at a high enough density fluctuation level and leading to a large jump of the reflected wave phase and a corresponding time delay is described analytically using a 1D model. Explicit expressions for the reflection and transmission coefficients are derived and compared against results of numerical modelling. The criteria for transition to the nonlinear regime of strong Bragg backscattering (BBS) is obtained for both O-mode and X-mode reflectometry. It is shown that a strong nonlinear regime of BBS may occur in ITER at the 0.5-2% relative density perturbation level both for the ordinary and extraordinary mode probing. The possibility of probing wave trapping leading to strong enhancement of the electric field and associated high phase variation of the reflected wave due to BBS is demonstrated.

  1. CGI delay compensation

    NASA Technical Reports Server (NTRS)

    Mcfarland, Richard E.

    1986-01-01

    Computer-generated graphics in real-time helicopter simulation produces objectionable scene-presentation time delays. In the flight simulation laboratory at Ames Research Center, it has been determined that these delays have an adverse influence on pilot performance during aggressive tasks such as nap-of-the-earth (NOE) maneuvers. Using contemporary equipment, computer-generated image (CGI) time delays are an unavoidable consequence of the operations required for scene generation. However, providing that magnitide distortions at higher frequencies are tolerable, delay compensation is possible over a restricted frequency range. This range, assumed to have an upper limit of perhaps 10 or 15 rad/sec, conforms approximately to the bandwidth associated with helicopter handling qualities research. A compensation algorithm is introduced here and evaluated in terms of tradeoffs in frequency responses. The algorithm has a discrete basis and accommodates both a large, constant transport delay interval and a periodic delay interval, as associated with asynchronous operations.

  2. VARIABLE TIME DELAY MEANS

    DOEpatents

    Clemensen, R.E.

    1959-11-01

    An electrically variable time delay line is described which may be readily controlled simuitaneously with variable impedance matching means coupied thereto such that reflections are prevented. Broadly, the delay line includes a signal winding about a magnetic core whose permeability is electrically variable. Inasmuch as the inductance of the line varies directly with the permeability, the time delay and characteristic impedance of the line both vary as the square root of the permeability. Consequently, impedance matching means may be varied similariy and simultaneously w:th the electrically variable permeability to match the line impedance over the entire range of time delay whereby reflections are prevented.

  3. Afterpulse and delayed crosstalk analysis on a STMicroelectronics silicon photomultiplier

    NASA Astrophysics Data System (ADS)

    Nagy, Ferenc; Mazzillo, Massimo; Renna, Lucio; Valvo, Giuseppina; Sanfilippo, Delfo; Carbone, Beatrice; Piana, Angelo; Fallica, Giorgio; Molnár, József

    2014-09-01

    Crosstalk and afterpulsing in silicon photomultipliers can strongly limit the photon-counting resolution and dynamic range of the sensors. In this work we present a method and a measurement (as a demonstration) to separate the afterpulse and delayed crosstalk components of the delayed correlated pulses in STMicroelectronics silicon photomultiplier signals. The contribution of delayed crosstalk can be significant since even if one suppresses afterpulses by applying a longer recharge time, the delayed crosstalk component remains unaffected. This was the case for our measurement: 207 ns recharge was long enough to suppress afterpulses (3.3%), while the delayed crosstalk remained large (12.8%).

  4. Digital time delay

    DOEpatents

    Martin, A.D.

    1986-05-09

    Method and apparatus are provided for generating an output pulse following a trigger pulse at a time delay interval preset with a resolution which is high relative to a low resolution available from supplied clock pulses. A first lumped constant delay provides a first output signal at predetermined interpolation intervals corresponding to the desired high resolution time interval. Latching circuits latch the high resolution data to form a first synchronizing data set. A selected time interval has been preset to internal counters and corrected for circuit propagation delay times having the same order of magnitude as the desired high resolution. Internal system clock pulses count down the counters to generate an internal pulse delayed by an internal which is functionally related to the preset time interval. A second LCD corrects the internal signal with the high resolution time delay. A second internal pulse is then applied to a third LCD to generate a second set of synchronizing data which is complementary with the first set of synchronizing data for presentation to logic circuits. The logic circuits further delay the internal output signal with the internal pulses. The final delayed output signal thereafter enables the output pulse generator to produce the desired output pulse at the preset time delay interval following input of the trigger pulse.

  5. IDENTIFYING ANOMALIES IN GRAVITATIONAL LENS TIME DELAYS

    SciTech Connect

    Congdon, Arthur B.; Keeton, Charles R.; Nordgren, C. Erik E-mail: keeton@physics.rutgers.ed

    2010-02-01

    We examine the ability of gravitational lens time delays to reveal complex structure in lens potentials. In a previous paper, we predicted how the time delay between the bright pair of images in a 'fold' lens scales with the image separation, for smooth lens potentials. Here we show that the proportionality constant increases with the quadrupole moment of the lens potential, and depends only weakly on the position of the source along the caustic. We use Monte Carlo simulations to determine the range of time delays that can be produced by realistic smooth lens models consisting of isothermal ellipsoid galaxies with tidal shear. We can then identify outliers as 'time delay anomalies'. We find evidence for anomalies in close image pairs in the cusp lenses RX J1131 - 1231 and B1422+231. The anomalies in RX J1131 - 1231 provide strong evidence for substructure in the lens potential, while at this point the apparent anomalies in B1422+231 mainly indicate that the time delay measurements need to be improved. We also find evidence for time delay anomalies in larger-separation image pairs in the fold lenses, B1608+656 and WFI 2033 - 4723, and the cusp lens RX J0911+0551. We suggest that these anomalies are caused by some combination of substructure and a complex lens environment. Finally, to assist future monitoring campaigns we use our smooth models with shear to predict the time delays for all known four-image lenses.

  6. Delayed flowering and global warming

    NASA Astrophysics Data System (ADS)

    Cook, B. I.; Wolkovich, E. M.; Parmesan, C.

    2011-12-01

    Within general trends toward earlier spring, observed cases of species and ecosystems that have not advanced their phenology, or have even delayed it, appear paradoxical, especially when made in temperate regions experiencing significant warming. The typical interpretation of this pattern has been that non-responders are insensitive to relatively small levels of warming over the past 40 years, while species showing delays are often viewed as statistical noise or evidence for unknown confounding factors at play. However, plant physiology studies suggest that when winter chilling (vernalization) is required to initiate spring development, winter warming may retard spring events, masking expected advances caused by spring warming. Here, we analyzed long-term data on phenology and seasonal temperatures from 490 species on two continents and demonstrate that 1) apparent non-responders are indeed responding to warming, but their responses to winter and spring warming are opposite in sign, 2) observed trends in first flowering date depend strongly on the magnitude of a given species' response to autumn/winter versus spring warming, and 3) inclusion of these effects strongly improves hindcast predictions of long-term flowering trends. With a few notable exceptions, climate change research has focused on the overall mean trend towards phenological advance, minimizing discussion of apparently non-responding species. Our results illuminate an under-studied source of complexity in wild species responses and support the need for models incorporating diverse environmental cues in order to improve predictability of species responses to anthropogenic climate change.

  7. Delayed neutrons in fission of polonium isotopes

    SciTech Connect

    Ramazanov, R.; Urikbaev, Z.S.; Maksyutenko, B.P.; Ignat'ev, S.V.

    1988-06-01

    A strong difference is found in the relative yields of delayed neutrons in the production of compound nuclei of polonium isotopes in reactions in which bismuth and lead are bombarded by various charged particles. The effect can be partially explained by the different lengths of the ..beta..-decay chains of the light and heavy fission products.

  8. Delayed emergence after anesthesia.

    PubMed

    Tzabazis, Alexander; Miller, Christopher; Dobrow, Marc F; Zheng, Karl; Brock-Utne, John G

    2015-06-01

    In most instances, delayed emergence from anesthesia is attributed to residual anesthetic or analgesic medications. However, delayed emergence can be secondary to unusual causes and present diagnostic dilemmas. Data from clinical studies is scarce and most available published material is comprised of case reports. In this review, we summarize and discuss less common and difficult to diagnose reasons for delayed emergence and present cases from our own experience or reference published case reports/case series. The goal is to draw attention to less common reasons for delayed emergence, identify patient populations that are potentially at risk and to help anesthesiologists identifying a possible cause why their patient is slow to wake up. PMID:25912729

  9. Time delay spectrum conditioner

    DOEpatents

    Greiner, Norman R.

    1980-01-01

    A device for delaying specified frequencies of a multiple frequency laser beam. The device separates the multiple frequency beam into a series of spatially separated single frequency beams. The propagation distance of the single frequency beam is subsequently altered to provide the desired delay for each specific frequency. Focusing reflectors can be utilized to provide a simple but nonadjustable system or, flat reflectors with collimating and focusing optics can be utilized to provide an adjustable system.

  10. Delayed voice communication

    NASA Astrophysics Data System (ADS)

    Love, Stanley G.; Reagan, Marcum L.

    2013-10-01

    We present results from simulated deep-space exploration missions that investigated voice communication with significant time delays. The simulations identified many challenges: confusion of sequence, blocked calls, wasted crew time, impaired ability to provide relevant information to the other party, losing track of which messages have reached the other party, weakened rapport between crew and ground, slow response to rapidly changing situations, and reduced situational awareness. These challenges were met in part with additional training; greater attention and foresight; longer, less frequent transmissions; meticulous recordkeeping and timekeeping; and specific alerting and acknowledging calls. Several simulations used both delayed voice and text messaging. Text messaging provided a valuable record of transmissions and allowed messages to be targeted to subsets of the flight and ground crew, but it was a poor choice for high-workload operators such as vehicle drivers and spacewalkers. Even with the foregoing countermeasures, delayed voice communication is difficult. Additional aids such as automatic delay timers and voice-to-text transcription would help. Tests comparing delays of 50 and 300 s unexpectedly revealed that communicating with the shorter delay was just as challenging as with the longer one.

  11. Downhole delay assembly for blasting with series delay

    DOEpatents

    Ricketts, Thomas E.

    1982-01-01

    A downhole delay assembly is provided which can be placed into a blasthole for initiation of explosive in the blasthole. The downhole delay assembly includes at least two detonating time delay devices in series in order to effect a time delay of longer than about 200 milliseconds in a round of explosions. The downhole delay assembly provides a protective housing to prevent detonation of explosive in the blasthole in response to the detonation of the first detonating time delay device. There is further provided a connection between the first and second time delay devices. The connection is responsive to the detonation of the first detonating time delay device and initiates the second detonating time delay device. A plurality of such downhole delay assemblies are placed downhole in unfragmented formation and are initiated simultaneously for providing a round of explosive expansions. The explosive expansions can be used to form an in situ oil shale retort containing a fragmented permeable mass of formation particles.

  12. Delay of Transition Using Forced Damping

    NASA Technical Reports Server (NTRS)

    Exton, Reginald J.

    2014-01-01

    Several experiments which have reported a delay of transition are analyzed in terms of the frequencies of the induced disturbances generated by different flow control elements. Two of the experiments employed passive stabilizers in the boundary layer, one leading-edge bluntness, and one employed an active spark discharge in the boundary layer. It is found that the frequencies generated by the various elements lie in the damping region of the associated stability curve. It is concluded that the creation of strong disturbances in the damping region stabilizes the boundary-layer and delays the transition from laminar to turbulent flow.

  13. The Vernier delay unit

    SciTech Connect

    Pierce, W.B.

    1985-02-01

    One of the most critical timing specifications for the SLC machine occurs at the injector and ejector magnets for the Damping Ring. It has been determined that the trigger pulses to the magnets must be controlled to 0.1 ns. The primary source for all trigger pulses for the SLC machine is the Programmable Delay Unit (PDU). The PDU generates a 67.2 ns wide pulse with delay increments of 8.7 ns. The gap between the required accuracy and that available from the PDU requires the design of a new module that is called the Vernier Delay Unit (VDU). This module accepts the 67.2 ns pulse from the PDU and is capable of increasing the delay in steps of 0.1 ns from 0 to 10.7 ns plus the minimum 9 ns delay. The module has two totally independent channels. The pulse input to the module is software selectable from either the auxiliary backplane or a front panel Lemo connector. The auxiliary backplane pulses are to be the 67 ns differential ECL pulses from the PDU. The front panel input is to be a NIM level (-0.7 V 50 termination).

  14. Consensus networks with time-delays over finite fields

    NASA Astrophysics Data System (ADS)

    Li, Xiuxian; Su, Housheng; Chen, Michael Z. Q.

    2016-05-01

    In this paper, we investigate the consensus problem in networks with time-delays over finite fields. The delays are categorised into three cases: single constant delay, multiple constant delays, and time-varying bounded delays. For all cases, some sufficient and necessary conditions for consensus are derived. Furthermore, assuming that the communication graph is strongly connected, some of the obtained necessary conditions reveal that the conditions for consensus with time-delays over finite fields depend not only on the diagonal entries but also on the off-diagonal entries, something that is intrinsically distinct from the case over real numbers (where having at least one nonzero diagonal entry is a sufficient and necessary condition to guarantee consensus). In addition, it is shown that delayed networks cannot achieve consensus when the interaction graph is a tree if the corresponding delay-free networks cannot reach consensus, which is consistent with the result over real numbers. As for average consensus, we show that it can never be achieved for delayed networks over finite fields, although it indeed can be reached under several conditions for delay-free networks over finite fields. Finally, networks with time-varying delays are discussed and one sufficient condition for consensus is presented by graph-theoretic method.

  15. A quantum delayed-choice experiment.

    PubMed

    Peruzzo, Alberto; Shadbolt, Peter; Brunner, Nicolas; Popescu, Sandu; O'Brien, Jeremy L

    2012-11-01

    Quantum systems exhibit particle- or wavelike behavior depending on the experimental apparatus they are confronted by. This wave-particle duality is at the heart of quantum mechanics. Its paradoxical nature is best captured in the delayed-choice thought experiment, in which a photon is forced to choose a behavior before the observer decides what to measure. Here, we report on a quantum delayed-choice experiment in which both particle and wave behaviors are investigated simultaneously. The genuinely quantum nature of the photon's behavior is certified via nonlocality, which here replaces the delayed choice of the observer in the original experiment. We observed strong nonlocal correlations, which show that the photon must simultaneously behave both as a particle and as a wave. PMID:23118183

  16. Contingencies promote delay tolerance.

    PubMed

    Ghaemmaghami, Mahshid; Hanley, Gregory P; Jessel, Joshua

    2016-09-01

    The effectiveness of functional communication training as treatment for problem behavior depends on the extent to which treatment can be extended to typical environments that include unavoidable and unpredictable reinforcement delays. Time-based progressive delay (TBPD) often results in the loss of acquired communication responses and the resurgence of problem behavior, whereas contingency-based progressive delay (CBPD) appears to be effective for increasing tolerance for delayed reinforcement. No direct comparison of TBPD and CBPD has, however, been conducted. We used single-subject designs to compare the relative efficacy of TBPD and CBPD. Four individuals who engaged in problem behavior (e.g., aggression, vocal and motor disruptions, self-injury) participated. Results were consistent across all participants, and showed lower rates of problem behavior and collateral responses during CBPD than during TBPD. The generality of CBPD treatment effects, including optimal rates of communication and compliance with demands, was demonstrated across a small but heterogeneous group of participants, reinforcement contingencies, and contexts. PMID:27449401

  17. Delayed traumatic diaphragmatic hernia

    PubMed Central

    Lu, Jing; Wang, Bo; Che, Xiangming; Li, Xuqi; Qiu, Guanglin; He, Shicai; Fan, Lin

    2016-01-01

    Abstract Background: Traumatic diaphragmatic hernias (TDHs) are sometimes difficult to identify at an early stage and can consequently result in diagnostic delays with life-threatening outcomes. It is the aim of this case study to highlight the difficulties encountered with the earlier detection of traumatic diaphragmatic hernias. Methods: Clinical data of patients who received treatment for delayed traumatic diaphragmatic hernias in registers of the First Affiliated Hospital of Xi’an Jiaotong University from 1998 to 2014 were analyzed retrospectively. Results: Six patients were included in this study. Left hemidiaphragm was affected in all of them. Most of the patients had a history of traffic accident and 1 a stab-penetrating injury. The interval from injury to developing symptoms ranged from 2 to 11 years (median 5 years). The hernial contents included the stomach, omentum, small intestine, and colon. Diaphragmatic injury was missed in all of them during the initial managements. All patients received operations once the diagnosis of delayed TDH was confirmed, and no postoperative mortality was detected. Conclusions: Delayed TDHs are not common, but can lead to serious consequences once occurred. Early detection of diaphragmatic injuries is crucial. Surgeons should maintain a high suspicion for injuries of the diaphragm in cases with abdominal or lower chest traumas, especially in the initial surgical explorations. We emphasize the need for radiographical follow-up to detect diaphragmatic injuries at an earlier stage. PMID:27512848

  18. Estimating Delays In ASIC's

    NASA Technical Reports Server (NTRS)

    Burke, Gary; Nesheiwat, Jeffrey; Su, Ling

    1994-01-01

    Verification is important aspect of process of designing application-specific integrated circuit (ASIC). Design must not only be functionally accurate, but must also maintain correct timing. IFA, Intelligent Front Annotation program, assists in verifying timing of ASIC early in design process. This program speeds design-and-verification cycle by estimating delays before layouts completed. Written in C language.

  19. Interferometric Propagation Delay

    NASA Technical Reports Server (NTRS)

    Goldstein, Richard

    1999-01-01

    Radar interferometry based on (near) exact repeat passes has lately been used by many groups of scientists, worldwide, to achieve state of the art measurements of topography, glacier and ice stream motion, earthquake displacements, oil field subsidence, lava flows, crop-induced surface decorrelation, and other effects. Variations of tropospheric and ionospheric propagation delays limit the accuracy of all such measurements. We are investigating the extent of this limitation, using data from the Shuttle radar flight, SIR-C, which is sensitive to the troposphere, and the Earth Resources Satellites, ERS-1/2, which are sensitive to both the troposphere and the ionosphere. We are presently gathering statistics of the delay variations over selected, diverse areas to determine the best accuracy possible for repeat track interferometry. The phases of an interferogram depend on both the topography of the scene and variations in propagation delay. The delay variations can be caused by movement of elements in the scene, by changes in tropospheric water vapor and by changes of the charge concentrations in the ionosphere. We plan to separate these causes by using the data from a third satellite visit (three-pass interferometry). The figure gives the geometry of the three-pass observations. The page of the figure is taken to be perpendicular to the spacecraft orbits. The three observational locations are marked on the figure, giving baselines B-12 and B-13, separated by the angle alpha. These parameters are almost constant over the whole scene. However, each pixel has an individual look angle, theta, which is related to the topography, rho is the slant range. A possible spurious time delay is shown. Additional information is contained in the original.

  20. Cosmological Applications of Strong Gravitational Lensing

    NASA Astrophysics Data System (ADS)

    Paraficz, Danuta

    2009-11-01

    One of the most intriguing recent results in physics is the growing evidence that an unknown energy field and an unknown kind of matter are the major components of the Universe (70% and 30%, respectively; see e.g. Riess et al. 1998, Spergel et al. 2007). Understanding and estimating the precise value of the energy density of the two above components, together with measuring the Hubble constant that determines the age of the Universe, is a major goal of modern astrophysics. An interesting method for estimating these parameters is strong gravitational lensing of quasars (QSOs). As shown by Refsdal (1964), H0, !m and !! can be measured based on the time delay ("t) between multiply lensed images of QSOs, because "t depends on H0 and on the distances to lens and source, hence!m and !!. Determination of cosmological parameters using gravitational lensing suffers from some degeneracies, but it is based on well understood physics and unlike distance ladder methods there are no calibration issues. Moreover, it has an advantage over some of the leading methods (such as Type Ia SNe) in that it is a purely cosmological approach. In this thesis, the property of strong gravitational lensing - time delay - is extensively explored. Strong gravitational lensing, and in particular time delays, are investigated here both theoretically and observationally. The focus is on the time delay as a cosmological and astrophysical tool to constrain H0, !m, !!, and to measure the masses of lensing galaxies. The first Chapter presents a historical background of gravitational lensing. It explains the process involved in creating the theory of gravitational lenses. It shows how Newton and then Einstein developed the concept and how Refsdal and others made it a cosmological tool. We present in more detail how gravitational lensing influenced the history of physics by being the first proof of Einstein's theory of gravity. The Chapter ends by discussing the first observational discovery of a strong

  1. [Acromegaly: reducing diagnostic delay].

    PubMed

    Giustina, Andrea

    2016-08-01

    Diagnostic delay of acromegaly is still very relevant (6-8 years on average) without substantial changes in last twenty years. Clinical impact of this diagnostic delay is significant: tumor growth (2/3 of the patients at diagnosis bear a pituitary macroadenoma), development of irreversible complications (arthropathy, sleep apnea) and in all increased mortality. Reasons for this delay are related to the disease itself (facial and acral changes are very slow and subtle) but also to medical unawareness. Simple tools based on a few sufficiently sensitive and specific signs and symptoms which can trigger the diagnostic suspect would be useful in clinical practice. Global evaluation during follow-up (tumor volume, signs and symptoms, complications, circulating levels of growth hormone and its peripheral mediator IGF-I) has become crucial for the therapeutic decision making. In this regard, tools like SAGIT are now under validation and are expected to improve management of acromegaly. In fact, in the last 30 years there has been a relevant growth of the medical options to treat acromegaly and in the near future there will be an expansion of the medical options. This will greatly help the needed personalization of treatment which necessarily should consider patient convenience and preference and control of complications such as diabetes mellitus. PMID:27571562

  2. Time-Delay Interferometry

    NASA Astrophysics Data System (ADS)

    Dhurandhar, Sanjeev V.; Tinto, Massimo

    2005-07-01

    Equal-arm interferometric detectors of gravitational radiation allow phase measurements many orders of magnitude below the intrinsic phase stability of the laser injecting light into their arms. This is because the noise in the laser light is common to both arms, experiencing exactly the same delay, and thus cancels when it is differenced at the photo detector. In this situation, much lower level secondary noises then set the overall performance. If, however, the two arms have different lengths (as will necessarily be the case with space-borne interferometers), the laser noise experiences different delays in the two arms and will hence not directly cancel at the detector. In order to solve this problem, a technique involving heterodyne interferometry with unequal arm lengths and independent phase-difference readouts has been proposed. It relies on properly time-shifting and linearly combining independent Doppler measurements, and for this reason it has been called Time-Delay Interferometry (TDI). This article provides an overview of the theory and mathematical foundations of TDI as it will be implemented by the forthcoming space-based interferometers such as the Laser Interferometer Space Antenna (LISA) mission. We have purposely left out from this first version of our "Living Review" article on TDI all the results of more practical and experimental nature, as well as all the aspects of TDI that the data analysts will need to account for when analyzing the LISA TDI data combinations. Our forthcoming "second edition" of this review paper will include these topics.

  3. Delay-correlation landscape reveals characteristic time delays of brain rhythms and heart interactions.

    PubMed

    Lin, Aijing; Liu, Kang K L; Bartsch, Ronny P; Ivanov, Plamen Ch

    2016-05-13

    Within the framework of 'Network Physiology', we ask a fundamental question of how modulations in cardiac dynamics emerge from networked brain-heart interactions. We propose a generalized time-delay approach to identify and quantify dynamical interactions between physiologically relevant brain rhythms and the heart rate. We perform empirical analysis of synchronized continuous EEG and ECG recordings from 34 healthy subjects during night-time sleep. For each pair of brain rhythm and heart interaction, we construct a delay-correlation landscape (DCL) that characterizes how individual brain rhythms are coupled to the heart rate, and how modulations in brain and cardiac dynamics are coordinated in time. We uncover characteristic time delays and an ensemble of specific profiles for the probability distribution of time delays that underly brain-heart interactions. These profiles are consistently observed in all subjects, indicating a universal pattern. Tracking the evolution of DCL across different sleep stages, we find that the ensemble of time-delay profiles changes from one physiologic state to another, indicating a strong association with physiologic state and function. The reported observations provide new insights on neurophysiological regulation of cardiac dynamics, with potential for broad clinical applications. The presented approach allows one to simultaneously capture key elements of dynamic interactions, including characteristic time delays and their time evolution, and can be applied to a range of coupled dynamical systems. PMID:27044991

  4. Assessing delay discounting in mice

    PubMed Central

    Mitchell, Suzanne H.

    2014-01-01

    Delay discounting (also intertemporal choice or impulsive choice) is the process by which delayed outcomes, such as delayed food delivery, are valued less than the same outcomes delivered immediately or with a shorter delay. This process is of interest because many psychopathologies, including substance dependence, pathological gambling, attention deficit hyperactivity disorder and conduct disorder, are characterized by heightened levels of delay discounting. Some of these disorders are heritable, and data indicate that delay discounting also has a genetic component. To identify the genes underlying the delay discounting decision-making process and genetic correlates of heightened discounting, researchers have used mouse models. This unit describes a protocol for generating delay discounting behavior in mice and discusses analysis techniques for such behavior. PMID:24510779

  5. Delayed Speech or Language Development

    MedlinePlus

    ... to Know About Zika & Pregnancy Delayed Speech or Language Development KidsHealth > For Parents > Delayed Speech or Language ... your child is right on schedule. Normal Speech & Language Development It's important to discuss early speech and ...

  6. Tooth formation - delayed or absent

    MedlinePlus

    Delayed or absent tooth formation; Teeth - delayed or absent formation ... The age at which the tooth comes in varies. Most infants get their first tooth between 6 and 9 months, but it may be earlier or later. ...

  7. Programmable Differential Delay Circuit With Fine Delay Adjustment

    DOEpatents

    DeRyckere, John F.; Jenkins, Philip Nord; Cornett, Frank Nolan

    2002-07-09

    Circuitry that provides additional delay to early arriving signals such that all data signals arrive at a receiving latch with same path delay. The delay of a forwarded clock reference is also controlled such that the capturing clock edge will be optimally positioned near quadrature (depending on latch setup/hold requirements). The circuitry continuously adapts to data and clock path delay changes and digital filtering of phase measurements reduce errors brought on by jittering data edges. The circuitry utilizes only the minimum amount of delay necessary to achieve objective thereby limiting any unintended jitter. Particularly, this programmable differential delay circuit with fine delay adjustment is designed to allow the skew between ASICS to be minimized. This includes skew between data bits, between data bits and clocks as well as minimizing the overall skew in a channel between ASICS.

  8. What Is Strong Correlation?

    ERIC Educational Resources Information Center

    Kozak, Marcin

    2009-01-01

    Interpretation of correlation is often based on rules of thumb in which some boundary values are given to help decide whether correlation is non-important, weak, strong or very strong. This article shows that such rules of thumb may do more harm than good, and instead of supporting interpretation of correlation--which is their aim--they teach a…

  9. Strong Navajo Marriages

    ERIC Educational Resources Information Center

    Skogrand, Linda; Mueller, Mary Lou; Arrington, Rachel; LeBlanc, Heidi; Spotted Elk, Davina; Dayzie, Irene; Rosenbrand, Reva

    2008-01-01

    The purpose of this qualitative study, conducted in two Navajo Nation chapters, was to learn what makes Navajo marriages strong because no research has been done on this topic. Twenty-one Navajo couples (42 individuals) who felt they had strong marriages volunteered to participate in the study. Couples identified the following marital strengths:…

  10. In-flight evaluation of pure time delays in pitch and roll

    NASA Technical Reports Server (NTRS)

    Berry, D. T.

    1985-01-01

    An in-flight investigation of the effect of pure time delays in pitch and roll was undertaken. The evaluation tasks consisted of low lift-to-drag-ratio landings of various levels of difficulty and formation flying. The results indicate that the effect of time delay is strongly dependent on the task. In the pitch axis, in calm air, spot landings from a lateral offset were most strongly influenced by time delay. In the roll axis, in calm air, formation flying was most strongly influenced by time delay. However, when landings were made in turbulence, flying qualities in pitch were only slightly degraded, whereas in roll they were severely degraded.

  11. Adaptive Phase Delay Generator

    NASA Technical Reports Server (NTRS)

    Greer, Lawrence

    2013-01-01

    There are several experimental setups involving rotating machinery that require some form of synchronization. The adaptive phase delay generator (APDG) the Bencic-1000 is a flexible instrument that allows the user to generate pulses synchronized to the rising edge of a tachometer signal from any piece of rotating machinery. These synchronized pulses can vary by the delay angle, pulse width, number of pulses per period, number of skipped pulses, and total number of pulses. Due to the design of the pulse generator, any and all of these parameters can be changed independently, yielding an unparalleled level of versatility. There are two user interfaces to the APDG. The first is a LabVIEW program that has the advantage of displaying all of the pulse parameters and input signal data within one neatly organized window on the PC monitor. Furthermore, the LabVIEW interface plots the rpm of the two input signal channels in real time. The second user interface is a handheld portable device that goes anywhere a computer is not accessible. It consists of a liquid-crystal display and keypad, which enable the user to control the unit by scrolling through a host of command menus and parameter listings. The APDG combines all of the desired synchronization control into one unit. The experimenter can adjust the delay, pulse width, pulse count, number of skipped pulses, and produce a specified number of pulses per revolution. Each of these parameters can be changed independently, providing an unparalleled level of versatility when synchronizing hardware to a host of rotating machinery. The APDG allows experimenters to set up quickly and generate a host of synchronizing configurations using a simple user interface, which hopefully leads to faster results.

  12. Vehicle barrier with access delay

    DOEpatents

    Swahlan, David J; Wilke, Jason

    2013-09-03

    An access delay vehicle barrier for stopping unauthorized entry into secure areas by a vehicle ramming attack includes access delay features for preventing and/or delaying an adversary from defeating or compromising the barrier. A horizontally deployed barrier member can include an exterior steel casing, an interior steel reinforcing member and access delay members disposed within the casing and between the casing and the interior reinforcing member. Access delay members can include wooden structural lumber, concrete and/or polymeric members that in combination with the exterior casing and interior reinforcing member act cooperatively to impair an adversarial attach by thermal, mechanical and/or explosive tools.

  13. Clustering in delay-coupled smooth and relaxational chemical oscillators

    NASA Astrophysics Data System (ADS)

    Blaha, Karen; Lehnert, Judith; Keane, Andrew; Dahms, Thomas; Hövel, Philipp; Schöll, Eckehard; Hudson, John L.

    2013-12-01

    We investigate cluster synchronization in networks of nonlinear systems with time-delayed coupling. Using a generic model for a system close to the Hopf bifurcation, we predict the order of appearance of different cluster states and their corresponding common frequencies depending upon coupling delay. We may tune the delay time in order to ensure the existence and stability of a specific cluster state. We qualitatively and quantitatively confirm these results in experiments with chemical oscillators. The experiments also exhibit strongly nonlinear relaxation oscillations as we increase the voltage, i.e., go further away from the Hopf bifurcation. In this regime, we find secondary cluster states with delay-dependent phase lags. These cluster states appear in addition to primary states with delay-independent phase lags observed near the Hopf bifurcation. Extending the theory on Hopf normal-form oscillators, we are able to account for realistic interaction functions, yielding good agreement with experimental findings.

  14. Delayed rule following

    PubMed Central

    Schmitt, David R.

    2001-01-01

    Although the elements of a fully stated rule (discriminative stimulus [SD], some behavior, and a consequence) can occur nearly contemporaneously with the statement of the rule, there is often a delay between the rule statement and the SD. The effects of this delay on rule following have not been studied in behavior analysis, but they have been investigated in rule-like settings in the areas of prospective memory (remembering to do something in the future) and goal pursuit. Discriminative events for some behavior can be event based (a specific setting stimulus) or time based. The latter are more demanding with respect to intention following and show age-related deficits. Studies suggest that the specificity with which the components of a rule (termed intention) are stated has a substantial effect on intention following, with more detailed specifications increasing following. Reminders of an intention, too, are most effective when they refer specifically to both the behavior and its occasion. Covert review and written notes are two effective strategies for remembering everyday intentions, but people who use notes appear not to be able to switch quickly to covert review. By focusing on aspects of the setting and rule structure, research on prospective memory and goal pursuit expands the agenda for a more complete explanation of rule effects. PMID:22478363

  15. Living Bones, Strong Bones

    NASA Video Gallery

    In this classroom activity, engineering, nutrition, and physical activity collide when students design and build a healthy bone model of a space explorer which is strong enough to withstand increas...

  16. Stability and delay sensitivity of neutral fractional-delay systems

    NASA Astrophysics Data System (ADS)

    Xu, Qi; Shi, Min; Wang, Zaihua

    2016-08-01

    This paper generalizes the stability test method via integral estimation for integer-order neutral time-delay systems to neutral fractional-delay systems. The key step in stability test is the calculation of the number of unstable characteristic roots that is described by a definite integral over an interval from zero to a sufficient large upper limit. Algorithms for correctly estimating the upper limits of the integral are given in two concise ways, parameter dependent or independent. A special feature of the proposed method is that it judges the stability of fractional-delay systems simply by using rough integral estimation. Meanwhile, the paper shows that for some neutral fractional-delay systems, the stability is extremely sensitive to the change of time delays. Examples are given for demonstrating the proposed method as well as the delay sensitivity.

  17. Stability and delay sensitivity of neutral fractional-delay systems.

    PubMed

    Xu, Qi; Shi, Min; Wang, Zaihua

    2016-08-01

    This paper generalizes the stability test method via integral estimation for integer-order neutral time-delay systems to neutral fractional-delay systems. The key step in stability test is the calculation of the number of unstable characteristic roots that is described by a definite integral over an interval from zero to a sufficient large upper limit. Algorithms for correctly estimating the upper limits of the integral are given in two concise ways, parameter dependent or independent. A special feature of the proposed method is that it judges the stability of fractional-delay systems simply by using rough integral estimation. Meanwhile, the paper shows that for some neutral fractional-delay systems, the stability is extremely sensitive to the change of time delays. Examples are given for demonstrating the proposed method as well as the delay sensitivity. PMID:27586618

  18. Soviet delays raise prices

    SciTech Connect

    Young, I.

    1992-01-15

    The breakup of the Soviet Union is causing massive disruptions to methanol exports. The changeover to a Commonwealth of independent States has created logistical problems which have led some shipments of Russian methanol to be cancelled and delayed other deliveries by up to two weeks. In recent years the Soviet Union has exported 700,000 m.t./year-900,000 m.t./year of methanol, mainly to Western Europe. The product is made at 750,000-m.t./year plants at Tomsk and Gubakha in Russia and transported by rail for shipment from the ports of Ventspils, Latvia, on the Baltic Sea and Yuzhnyy in Ukraine, on the Black Sea. The exports were handled by state export agency Soyuzagrochim, mainly under contract to West European traders and consumers in areas like Scandinavia and France.

  19. Delayed cure bismaleimide resins

    DOEpatents

    Adams, Johnnie E.; Jamieson, Donald R.

    1984-08-07

    Polybismaleimides prepared by delayed curing of bis-imides having the formula ##STR1## wherein R.sub.1 and R.sub.2 each independently is H, C.sub.1-4 -alkyl, C.sub.1-4 -alkoxy, Cl or Br, or R.sub.1 and R.sub.2 together form a fused 6-membered hydrocarbon aromatic ring, with the proviso that R.sub.1 and R.sub.2 are not t-butyl or t-butoxy; X is O, S or Se; n is 1-3; and the --(CH.sub.2).sub.n -- group, optionally, is substituted by 1-3 methyl groups or by fluorine.

  20. Cochlear implant and delayed facial palsy.

    PubMed

    Joseph, Shawn Thadathil; Vishwakarma, Rajesh; Ramani, Mukesh Kumar; Aurora, Rupa

    2009-12-01

    Delayed facial nerve palsy following cochlear implant surgery is less documented though it poses diagnostic and therapeutic challenges. Apart from the functional, aesthetic and emotional concerns, it can raise important medico legal issues. The objectives of this study were: to report a case of delayed facial palsy following cochlear implant surgery in a patient who had positive viral antibody markers pre operatively; and to review the literature on delayed onset facial paralysis following viral reactivation and its relation to cochlear implant surgery. An extensive literature review was done using internet and medical search engines and library facilities. Important articles on the topic were identified and summarised. Data on delayed facial palsy following cochlear implant surgery were collected, constructed in a coherent way and details discussed. Postulated mechanisms of delayed facial palsy include neural oedema, vasospasm and viral reactivation. Of these, reactivation of previous herpes simplex virus infection has special significance, as many of these patients are positive for viral antibody markers. Manipulation of sensory branches of the facial nerve and chorda tympani can be a mechanism in such cases. Correlation of clinical presentation and pre operative positive viral antibody markers with positive polymerase chain reaction can be strongly suggestive of viral reactivation. It is concluded that patients with positive viral antibody markers are more susceptible to facial palsy from viral reactivation. Corticosteroids, antiviral agents and physiotherapy can be useful in producing a quicker and complete recovery. An experienced cochlear implant surgery team and pre operative radiological evaluations are mandatory to decrease the chances of direct facial nerve trauma. Proper irrigation lowers the risk of neural oedema. PMID:19194876

  1. Strong acoustic wave action

    NASA Astrophysics Data System (ADS)

    Gokhberg, M. B.

    1983-07-01

    Experiments devoted to acoustic action on the atmosphere-magnetosphere-ionosphere system using ground based strong explosions are reviewed. The propagation of acoustic waves was observed by ground observations over 2000 km in horizontal direction and to an altitude of 200 km. Magnetic variations up to 100 nT were detected by ARIEL-3 satellite near the epicenter of the explosion connected with the formation of strong field aligned currents in the magnetosphere. The enhancement of VLF emission at 800 km altitude is observed.

  2. Modeling delay in genetic networks: From delay birth-death processes to delay stochastic differential equations

    PubMed Central

    Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Bennett, Matthew R.; Josić, Krešimir; Ott, William

    2014-01-01

    Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay. PMID:24880267

  3. Modeling delay in genetic networks: From delay birth-death processes to delay stochastic differential equations

    SciTech Connect

    Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Ott, William; Bennett, Matthew R.; Josić, Krešimir

    2014-05-28

    Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay.

  4. PRECISION TIME-DELAY CIRCUIT

    DOEpatents

    Creveling, R.

    1959-03-17

    A tine-delay circuit which produces a delay time in d. The circuit a capacitor, an te back resistance, connected serially with the anode of the diode going to ground. At the start of the time delay a negative stepfunction is applied to the series circuit and initiates a half-cycle transient oscillatory voltage terminated by a transient oscillatory voltage of substantially higher frequency. The output of the delay circuit is taken at the junction of the inductor and diode where a sudden voltage rise appears after the initiation of the higher frequency transient oscillations.

  5. Time Delay of CGM Sensors

    PubMed Central

    Schmelzeisen-Redeker, Günther; Schoemaker, Michael; Kirchsteiger, Harald; Freckmann, Guido; Heinemann, Lutz; del Re, Luigi

    2015-01-01

    Background: Continuous glucose monitoring (CGM) is a powerful tool to support the optimization of glucose control of patients with diabetes. However, CGM systems measure glucose in interstitial fluid but not in blood. Rapid changes in one compartment are not accompanied by similar changes in the other, but follow with some delay. Such time delays hamper detection of, for example, hypoglycemic events. Our aim is to discuss the causes and extent of time delays and approaches to compensate for these. Methods: CGM data were obtained in a clinical study with 37 patients with a prototype glucose sensor. The study was divided into 5 phases over 2 years. In all, 8 patients participated in 2 phases separated by 8 months. A total number of 108 CGM data sets including raw signals were used for data analysis and were processed by statistical methods to obtain estimates of the time delay. Results: Overall mean (SD) time delay of the raw signals with respect to blood glucose was 9.5 (3.7) min, median was 9 min (interquartile range 4 min). Analysis of time delays observed in the same patients separated by 8 months suggests a patient dependent delay. No significant correlation was observed between delay and anamnestic or anthropometric data. The use of a prediction algorithm reduced the delay by 4 minutes on average. Conclusions: Prediction algorithms should be used to provide real-time CGM readings more consistent with simultaneous measurements by SMBG. Patient specificity may play an important role in improving prediction quality. PMID:26243773

  6. Strong Little Magnets

    ERIC Educational Resources Information Center

    Moloney, Michael J.

    2007-01-01

    Did you know that some strong little cylindrical magnets available in local hardware stores can have an effective circumferential current of 2500 A? This intriguing information can be obtained by hanging a pair of magnets at the center of a coil, as shown in Fig. 1, and measuring the oscillation frequency as a function of coil current.

  7. A strong comeback

    SciTech Connect

    Marier, D.

    1992-03-01

    This article presents the results of a financial rankings survey which show a strong economic activity in the independent energy industry. The topics of the article include advisor turnover, overseas banks, and the increase in public offerings. The article identifies the top project finance investors for new projects and restructurings and rankings for lenders.

  8. Kernel regression estimates of time delays between gravitationally lensed fluxes

    NASA Astrophysics Data System (ADS)

    AL Otaibi, Sultanah; Tiňo, Peter; Cuevas-Tello, Juan C.; Mandel, Ilya; Raychaudhury, Somak

    2016-06-01

    Strongly lensed variable quasars can serve as precise cosmological probes, provided that time delays between the image fluxes can be accurately measured. A number of methods have been proposed to address this problem. In this paper, we explore in detail a new approach based on kernel regression estimates, which is able to estimate a single time delay given several data sets for the same quasar. We develop realistic artificial data sets in order to carry out controlled experiments to test the performance of this new approach. We also test our method on real data from strongly lensed quasar Q0957+561 and compare our estimates against existing results.

  9. Cosmological test using strong gravitational lensing systems

    NASA Astrophysics Data System (ADS)

    Yuan, C. C.; Wang, F. Y.

    2015-09-01

    As one of the probes of universe, strong gravitational lensing systems allow us to compare different cosmological models and constrain vital cosmological parameters. This purpose can be reached from the dynamic and geometry properties of strong gravitational lensing systems, for instance, time-delay Δτ of images, the velocity dispersion σ of the lensing galaxies and the combination of these two effects, Δτ/σ2. In this paper, in order to carry out one-on-one comparisons between ΛCDM universe and Rh = ct universe, we use a sample containing 36 strong lensing systems with the measurement of velocity dispersion from the Sloan Lens Advanced Camera for Surveys (SLACS) and Lens Structure and Dynamic survey (LSD) survey. Concerning the time-delay effect, 12 two-image lensing systems with Δτ are also used. In addition, Monte Carlo simulations are used to compare the efficiency of the three methods as mentioned above. From simulations, we estimate the number of lenses required to rule out one model at the 99.7 per cent confidence level. Comparing with constraints from Δτ and the velocity dispersion σ, we find that using Δτ/σ2 can improve the discrimination between cosmological models. Despite the independence tests of these methods reveal a correlation between Δτ/σ2 and σ, Δτ/σ2 could be considered as an improved method of σ if more data samples are available.

  10. Tunable optical delay via carrier induced exciton dephasing in semiconductor quantum wells.

    PubMed

    Sarkar, Susanta; Guo, Yan; Wang, Hailin

    2006-04-01

    We report the experimental realization of a tunable optical delay by exploiting unique incoherent nonlinear optical processes in semiconductors. The tunable optical delay takes advantage of the strong Coulomb interactions between excitons and free carriers and uses optical injection of free carriers to broaden and bleach an exciton absorption resonance. Fractional delay exceeding 200% has been obtained for an 8 ps optical pulse propagating near the heavy-hole excitonic transition in a GaAs quantum well structure. Tunable optical delay based on optical injection of free carriers avoids strong absorption of the pump beam and is also robust against variations in the frequency of the pump beam. PMID:19516421

  11. Delay Adjusted Incidence Infographic

    Cancer.gov

    This Infographic shows the National Cancer Institute SEER Incidence Trends. The graphs show the Average Annual Percent Change (AAPC) 2002-2011. For Men, Thyroid: 5.3*,Liver & IBD: 3.6*, Melanoma: 2.3*, Kidney: 2.0*, Myeloma: 1.9*, Pancreas: 1.2*, Leukemia: 0.9*, Oral Cavity: 0.5, Non-Hodgkin Lymphoma: 0.3*, Esophagus: -0.1, Brain & ONS: -0.2*, Bladder: -0.6*, All Sites: -1.1*, Stomach: -1.7*, Larynx: -1.9*, Prostate: -2.1*, Lung & Bronchus: -2.4*, and Colon & Rectum: -3/0*. For Women, Thyroid: 5.8*, Liver & IBD: 2.9*, Myeloma: 1.8*, Kidney: 1.6*, Melanoma: 1.5, Corpus & Uterus: 1.3*, Pancreas: 1.1*, Leukemia: 0.6*, Brain & ONS: 0, Non-Hodgkin Lymphoma: -0.1, All Sites: -0.1, Breast: -0.3, Stomach: -0.7*, Oral Cavity: -0.7*, Bladder: -0.9*, Ovary: -0.9*, Lung & Bronchus: -1.0*, Cervix: -2.4*, and Colon & Rectum: -2.7*. * AAPC is significantly different from zero (p<.05). Rates were adjusted for reporting delay in the registry. www.cancer.gov Source: Special section of the Annual Report to the Nation on the Status of Cancer, 1975-2011.

  12. Delayed unlatching mechanism

    DOEpatents

    Bzorgi, Fariborz M.

    2015-05-19

    In various embodiments an apparatus is presented for securing a structure such as a door, window, hatch, or gate that moves between an open and a closed position relative to a fixed structure to provide or deny access to a compartment, a room, an outdoor area, or a facility. Various embodiments provide a delay in opening the closure of sufficient duration to frustrate a rapid activation that might be desired by a person who is attempting to pass through the closure for some illicit purpose. Typically, hydraulics are used to activate the apparatus and no electrical energy or electronic signals are employed. In one embodiment, a plurality of actuations of a hand lever operates a hydraulic pump that moves a locking bolt from a first position in which a locking bolt is engaged with a recess in the fixed structure (preventing opening of a gate) to a second position in which the locking bolt is disengaged from the recess to permit opening of the gate.

  13. Delayed magnetic catalysis

    NASA Astrophysics Data System (ADS)

    Braun, Jens; Mian, Walid Ahmed; Rechenberger, Stefan

    2016-04-01

    We study the effect of an external magnetic field on the chiral phase transition in the theory of the strong interaction by means of a renormalization-group (RG) fixed-point analysis, relying on only one physical input parameter, the strong coupling at a given large momentum scale. To be specific, we consider the interplay of the RG flow of four-quark interactions and the running gauge coupling. Depending on the temperature and the strength of the magnetic field, the gauge coupling can drive the quark sector to criticality, resulting in chiral symmetry breaking. In accordance with lattice Monte-Carlo simulations, we find that the chiral phase transition temperature decreases for small values of the external magnetic field. For large magnetic field strengths, however, our fixed-point study predicts that the phase transition temperature increases monotonically.

  14. Development of a strong electromagnet wiggler

    SciTech Connect

    Burns, M.J.; Deis, G.A.; Holmes, R.H.; Van Maren, R.D.; Halbach, K.

    1987-01-01

    The Strong Electromagnet (SEM) wiggler is a permanent magnet-assisted electromagnet under development at the Lawrence Livermore National Laboratory (LLNL) as part of the Induction Linac Free-Electron-Laser (IFEL) program. This concept uses permanent magnets within the wiggler to provide a reverse bias flux in the iron and thus delay the onset of magnetic saturation. The electromagnet coils determine the wiggler field and operate at low current densities by virtue of their placement away from the midplane. We describe here the design approach used and test data from a 7-period wiggler prototype that includes curved pole tips to provide wiggle-plane focusing. 7 refs.

  15. Calibrating for Ionospheric Phase Delays

    NASA Technical Reports Server (NTRS)

    Macdoran, P. F.

    1985-01-01

    Technique determines ionospheric phase delay on real-time universally applicable basis in terms of electrons per meter squared by coherently modulating two L-band carrier frequencies received from two Global Positioning System satelites. Two pseudorandom number sequences cross-correlated to derive delay time.

  16. Delayed Auditory Feedback and Movement

    ERIC Educational Resources Information Center

    Pfordresher, Peter Q.; Dalla Bella, Simone

    2011-01-01

    It is well known that timing of rhythm production is disrupted by delayed auditory feedback (DAF), and that disruption varies with delay length. We tested the hypothesis that disruption depends on the state of the movement trajectory at the onset of DAF. Participants tapped isochronous rhythms at a rate specified by a metronome while hearing DAF…

  17. Linear rotary optical delay lines.

    PubMed

    Skorobogatiy, Maksim

    2014-05-19

    I present several classes of analytical and semi-analytical solutions for the design of high-speed rotary optical delay lines that use a combination of stationary and rotating curvilinear reflectors. Detailed analysis of four distinct classes of optical delay lines is presented. Particularly, I consider delay lines based on a single rotating reflector, a single rotating reflector and a single stationary reflector, two rotating reflectors, and two rotating reflectors and a single stationary reflector. I demonstrate that in each of these cases it is possible to design an infinite variety of the optical delay lines featuring linear dependence of the optical delay on the rotation angle. This is achieved via shape optimization of the rotating and stationary reflector surfaces. Moreover, in the case of two rotating reflectors a convenient spatial separation of the incoming and outgoing beams is possible. For the sake of example, all the blades presented in this paper are chosen to fit into a circle of 10 cm diameter and these delay lines feature in excess of 600 ps of optical delay. Finally, two prototypes of rotary delay lines were fabricated using CNC machining, and their optical properties are characterized. PMID:24921303

  18. High resolution digital delay timer

    DOEpatents

    Martin, Albert D.

    1988-01-01

    Method and apparatus are provided for generating an output pulse following a trigger pulse at a time delay interval preset with a resolution which is high relative to a low resolution available from supplied clock pulses. A first lumped constant delay (20) provides a first output signal (24) at predetermined interpolation intervals corresponding to the desired high resolution time interval. Latching circuits (26, 28) latch the high resolution data (24) to form a first synchronizing data set (60). A selected time interval has been preset to internal counters (142, 146, 154) and corrected for circuit propagation delay times having the same order of magnitude as the desired high resolution. Internal system clock pulses (32, 34) count down the counters to generate an internal pulse delayed by an interval which is functionally related to the preset time interval. A second LCD (184) corrects the internal signal with the high resolution time delay. A second internal pulse is then applied to a third LCD (74) to generate a second set of synchronizing data (76) which is complementary with the first set of synchronizing data (60) for presentation to logic circuits (64). The logic circuits (64) further delay the internal output signal (72) to obtain a proper phase relationship of an output signal (80) with the internal pulses (32, 34). The final delayed output signal (80) thereafter enables the output pulse generator (82) to produce the desired output pulse (84) at the preset time delay interval following input of the trigger pulse (10, 12).

  19. Delayed Reinforcement of Operant Behavior

    ERIC Educational Resources Information Center

    Lattal, Kennon A.

    2010-01-01

    The experimental analysis of delay of reinforcement is considered from the perspective of three questions that seem basic not only to understanding delay of reinforcement but also, by implication, the contributions of temporal relations between events to operant behavior. The first question is whether effects of the temporal relation between…

  20. Strong subadditivity and holography

    NASA Astrophysics Data System (ADS)

    Prudenziati, Andrea

    2016-05-01

    We study in detail the relationship between strong subadditivity for a boundary field theory and energy conditions for its bulk dual in 2 +1 dimensions. We provide a discussion of known facts and new results organized from the simplest case of a static system with collinear intervals to a time-dependent one in a generic configuration, with particular focus on the holographic geometric description.

  1. Plasmons in strong superconductors

    SciTech Connect

    Baldo, M.; Ducoin, C.

    2011-10-15

    We present a study of the possible plasmon excitations that can occur in systems where strong superconductivity is present. In these systems the plasmon energy is comparable to or smaller than the pairing gap. As a prototype of these systems we consider the proton component of Neutron Star matter just below the crust when electron screening is not taken into account. For the realistic case we consider in detail the different aspects of the elementary excitations when the proton, electron components are considered within the Random-Phase Approximation generalized to the superfluid case, while the influence of the neutron component is considered only at qualitative level. Electron screening plays a major role in modifying the proton spectrum and spectral function. At the same time the electron plasmon is strongly modified and damped by the indirect coupling with the superfluid proton component, even at moderately low values of the gap. The excitation spectrum shows the interplay of the different components and their relevance for each excitation modes. The results are relevant for neutrino physics and thermodynamical processes in neutron stars. If electron screening is neglected, the spectral properties of the proton component show some resemblance with the physical situation in high-T{sub c} superconductors, and we briefly discuss similarities and differences in this connection. In a general prospect, the results of the study emphasize the role of Coulomb interaction in strong superconductors.

  2. Discounting in Pigeons When the Choice is between Two Delayed Rewards: Implications for Species Comparisons.

    PubMed

    Calvert, Amanda L; Green, Leonard; Myerson, Joel

    2011-01-01

    Studies of delay discounting typically have involved choices between smaller, immediate outcomes and larger, delayed outcomes. In a study of delay discounting in humans, Green et al. (2005) added a period of time prior to both outcomes, creating a delay common to both. They found that the subjective value of the more delayed reward was well described by a hyperboloid discounting function and that the degree to which that outcome was discounted decreased as the common delay increased. In two experiments, we examined the effect of adding a common delay on the discounting of food rewards in pigeons. In Experiment 1, an adjusting-amount procedure was used to establish discounting functions when the common delay was 0, 3, 5, and 10 s, and different stimuli signaled time to the smaller, sooner and larger, later rewards. In contrast to humans, the pigeons showed increases in the degree of discounting when a common delay was added. In Experiment 2, the delay common to both rewards and the delay unique to the larger, later reward were each specifically signaled. With this procedure, the degree of discounting decreased as the common delay increased, a result consistent with that obtained with humans (Green et al., 2005). These findings reveal fundamental similarities between pigeons' and humans' choice behavior, and provide strong interspecies support for the hypothesis that choice between delayed outcomes is based on comparison of their hyperbolically discounted present subjective values. PMID:21887130

  3. Delay discounting of different commodities.

    PubMed

    Weatherly, Jeffrey N; Terrell, Heather K; Derenne, Adam

    2010-01-01

    When outcomes are delayed, their value is decreased. Delay discounting is a much-studied topic because it is correlated with certain disorders (e.g., pathological gambling). The present study attempts to determine how people would delay discount a number of different commodities, ranging from money to dating partners to federal education legislation. Participants completed delay discounting tasks pertaining to 5 different commodities, with a different set of 5 commodities for 2 groups. Results showed that different commodities were often discounted differently. Both data sets were also subjected to factor analysis. A 2-factor solution was found for both, suggesting that there are multiple "domains" of commodities. This finding is of interest because it suggests that measuring delay discounting for one commodity within a particular domain of commodities will be predictive of how people discount other commodities within that domain but will not be predictive of how they discount commodities within another domain. PMID:20718227

  4. Local Effects of Delayed Food

    PubMed Central

    Davison, Michael; Baum, William M

    2007-01-01

    Five pigeons were trained on a procedure in which seven concurrent variable-interval schedules arranged seven different food–rate ratios in random sequence in each session. Each of these components lasted for 10 response-produced food deliveries, and components were separated by 10-s blackouts. We varied delays to food (signaled by blackout) between the two response alternatives in an experiment with three phases: In Phase 1, the delay on one alternative was 0 s, and the other was varied between 0 and 8 s; in Phase 2, both delays were equal and were varied from 0 to 4 s; in Phase 3, the two delays summed to 8 s, and each was varied from 1 to 7 s. The results showed that increasing delay affected local choice, measured by a pulse in preference, in the same way as decreasing magnitude, but we found also that increasing the delay at the other alternative increased local preference. This result casts doubt on the traditional view that a reinforcer strengthens a response depending only on the reinforcer's value discounted by any response–reinforcer delay. The results suggest that food guides, rather than strengthens, behavior. PMID:17465314

  5. Attosecond Delays in Molecular Photoionization.

    PubMed

    Huppert, Martin; Jordan, Inga; Baykusheva, Denitsa; von Conta, Aaron; Wörner, Hans Jakob

    2016-08-26

    We report measurements of energy-dependent photoionization delays between the two outermost valence shells of N_{2}O and H_{2}O. The combination of single-shot signal referencing with the use of different metal foils to filter the attosecond pulse train enables us to extract delays from congested spectra. Remarkably large delays up to 160 as are observed in N_{2}O, whereas the delays in H_{2}O are all smaller than 50 as in the photon-energy range of 20-40 eV. These results are interpreted by developing a theory of molecular photoionization delays. The long delays measured in N_{2}O are shown to reflect the population of molecular shape resonances that trap the photoelectron for a duration of up to ∼110 as. The unstructured continua of H_{2}O result in much smaller delays at the same photon energies. Our experimental and theoretical methods make the study of molecular attosecond photoionization dynamics accessible. PMID:27610849

  6. Earth system commitments due to delayed mitigation

    NASA Astrophysics Data System (ADS)

    Pfister, Patrik L.; Stocker, Thomas F.

    2016-01-01

    As long as global CO2 emissions continue to increase annually, long-term committed Earth system changes grow much faster than current observations. A novel metric linking this future growth to policy decisions today is the mitigation delay sensitivity (MDS), but MDS estimates for Earth system variables other than peak temperature (ΔT max) are missing. Using an Earth System Model of Intermediate Complexity, we show that the current emission increase rate causes a ΔT max increase roughly 3-7.5 times as fast as observed warming, and a millenial steric sea level rise (SSLR) 7-25 times as fast as observed SSLR, depending on the achievable rate of emission reductions after the peak of emissions. These ranges are only slightly affected by the uncertainty range in equilibrium climate sensitivity, which is included in the above values. The extent of ocean acidification at the end of the century is also strongly dependent on the starting time and rate of emission reductions. The preservable surface ocean area with sufficient aragonite supersaturation for coral reef growth is diminished globally at an MDS of roughly 25%-80% per decade. A near-complete loss of this area becomes unavoidable if mitigation is delayed for a few years to decades. Also with respect to aragonite, 12%-18% of the Southern Ocean surface become undersaturated per decade, if emission reductions are delayed beyond 2015-2040. We conclude that the consequences of delaying global emission reductions are much better captured if the MDS of relevant Earth system variables is communicated in addition to current trends and total projected future changes.

  7. Fragmentation of long-lived hydrocarbons after strong field ionization

    NASA Astrophysics Data System (ADS)

    Larimian, Seyedreza; Erattupuzha, Sonia; Lötstedt, Erik; Szidarovszky, Tamás; Maurer, Raffael; Roither, Stefan; Schöffler, Markus; Kartashov, Daniil; Baltuška, Andrius; Yamanouchi, Kaoru; Kitzler, Markus; Xie, Xinhua

    2016-05-01

    We experimentally and theoretically investigated the deprotonation process on nanosecond to microsecond timescales in ethylene and acetylene molecules following their double ionization by a strong femtosecond laser field. In our experiments we utilized coincidence detection with the reaction microscope technique. We found that both the lifetime of the long-lived ethylene dication leading to the delayed deprotonation and the relative channel strength of the delayed deprotonation compared to the prompt one have no evident dependence on the laser pulse duration and the laser peak intensity. Quantum chemical simulations suggest that the observed delayed fragmentation process originates from the tunneling from near-dissociation-threshold C-H stretch vibrational states on a dicationic electronic state. These vibrational states can be populated through strong field double-ionization-induced vibrational excitation on an electronically excited state in the case of ethylene, and through a spin-flip transition from electronically excited singlet states to the triplet ground state in the case of acetylene.

  8. Temporal discrimination and delayed reinforcement.

    PubMed

    Buriticá, Jonathan; Vilchez, Zirahuén; Santos, Cristiano Valerio Dos

    2016-09-01

    We attempted to determine the effect of reinforcement delay on time discrimination in an interval bisection task. Three groups of rats were exposed to immediate, delayed reinforcement and longer signals with immediate reinforcement in acquisition and test. Results show differences in the amount of training necessary to reach the acquisition criteria, the Weber fraction and the range or overall stimulus control. The results suggest an increased difficulty to discriminate the difference among durations rather than an increase in estimated time as main effect of delayed reinforcement. PMID:27431922

  9. Strongly correlated electronic materials

    SciTech Connect

    Bedell, K.; Albers, R.; Balatsky, A.; Bishop, A.; Bonca, J.; Gubernatis, J.; Gulasci, M.; Silver, R.; Trugman, S.

    1996-04-01

    This is the final report of a 3-year project. Novel electronic materials characterized by strong electronic correlations display a number of unexpected, often extraordinary, properties. These are likely to play a major role in purpose-specific high-technology electronic materials of the future developed for electronic, magnetic, and optical applications. This project sought to develop predictive control of the novel properties by formulating, solving and applying many-body models for the underlying microscopic physics. This predictive control required the development of new analytical and numerical many-body techniques and strategies for materials of varying strengths of interactions, dimensionality and geometry. Results are compared with experiment on classes of novel materials, and the robust techniques are used to predict additional properties and motivate key additional experiments.

  10. Strongly-correlated heterostructures

    SciTech Connect

    Okamoto, Satoshi

    2012-01-01

    Electronic phase behavior in correlated-electron systems is a fundamental problem of condensed matter physics. The change in the phase behavior near surfaces and interfaces, i.e., {\\em electronic reconstruction}, is therefore the fundamental issue of the correlated-electron surface or interface science. In addition to basic science, understanding of such a phase behavior is of crucial importance for potential devices exploiting the novel properties of the correlated systems. In this article, we present a general overview of the field, and then discuss the recent theoretical progress mainly focusing on the correlation effects. We illustrate the general concept of {\\em electronic reconstruction} by studying model heterostructures consisting of strongly-correlated systems. Future directions for research are also discussed.

  11. Strong, Lightweight, Porous Materials

    NASA Technical Reports Server (NTRS)

    Leventis, Nicholas; Meador, Mary Ann B.; Johnston, James C.; Fabrizio, Eve F.; Ilhan, Ulvi

    2007-01-01

    A new class of strong, lightweight, porous materials has been invented as an outgrowth of an effort to develop reinforced silica aerogels. The new material, called X-Aerogel is less hygroscopic, but no less porous and of similar density to the corresponding unmodified aerogels. However, the property that sets X-Aerogels apart is their mechanical strength, which can be as much as two and a half orders of magnitude stronger that the unmodified aerogels. X-Aerogels are envisioned to be useful for making extremely lightweight, thermally insulating, structural components, but they may also have applications as electrical insulators, components of laminates, catalyst supports, templates for electrode materials, fuel-cell components, and filter membranes.

  12. 78 FR 59422 - Delayed Applications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-26

    ... Pipeline and Hazardous Materials Safety Administration Delayed Applications AGENCY: Office of Hazardous Materials Safety, Pipeline and Hazardous Materials Safety Administration (PHMSA), DOT. ACTION: List of... Paquet, Director, Office of Hazardous Materials Special Permits and Approvals, Pipeline and...

  13. Delay in cutaneous melanoma diagnosis

    PubMed Central

    Xavier, Marcus H.S.B.; Drummond-Lage, Ana P.; Baeta, Cyntia; Rocha, Lorena; Almeida, Alessandra M.; Wainstein, Alberto J.A.

    2016-01-01

    Abstract Advanced melanoma is an incurable disease with complex and expensive treatments. The best approach to prevent melanoma at advanced stages is an early diagnosis. A knowledge of factors associated with the process of detecting cutaneous melanomas and the reasons for delays in diagnosis is essential for the improvement of the secondary prevention of the disease. Identify sociodemographic, individual, and medical aspects related to cutaneous melanoma diagnosis delay. Interviews evaluated the knowledge of melanoma, signals, symptoms, persons who were suspected, delays in seeking medical attention, physician's deferrals, and related factors of 211 patients. Melanomas were self-discovered in 41.7% of the patients; healthcare providers detected 29.9% of patients and others detected 27%. The main component in delay was patient-related. Only 31.3% of the patients knew that melanoma was a serious skin cancer, and most thought that the pigmented lesion was not important, causing a delay in seeking medical assistance. Patients (36.4%) reported a wait interval of more than 6 months from the onset of an observed change in a pigmented lesion to the first visit to a physician. The delay interval from the first physician visit to a histopathological diagnosis was shorter (<1 month) in 55.5% of patients. Improper treatments without a histopathological confirmation occurred in 14.7% of patients. A professional delay was related to both inappropriate treatments performed without histopathological confirmation (P = 0.003) and long requirements for medical referrals (P < 0.001). A deficient knowledge in the population regarding melanoma and physicians’ misdiagnoses regarding suspicious lesions contributed to delays in diagnosis. PMID:27495055

  14. Measuring Information-Transfer Delays

    PubMed Central

    Wibral, Michael; Pampu, Nicolae; Priesemann, Viola; Siebenhühner, Felix; Seiwert, Hannes; Lindner, Michael; Lizier, Joseph T.; Vicente, Raul

    2013-01-01

    In complex networks such as gene networks, traffic systems or brain circuits it is important to understand how long it takes for the different parts of the network to effectively influence one another. In the brain, for example, axonal delays between brain areas can amount to several tens of milliseconds, adding an intrinsic component to any timing-based processing of information. Inferring neural interaction delays is thus needed to interpret the information transfer revealed by any analysis of directed interactions across brain structures. However, a robust estimation of interaction delays from neural activity faces several challenges if modeling assumptions on interaction mechanisms are wrong or cannot be made. Here, we propose a robust estimator for neuronal interaction delays rooted in an information-theoretic framework, which allows a model-free exploration of interactions. In particular, we extend transfer entropy to account for delayed source-target interactions, while crucially retaining the conditioning on the embedded target state at the immediately previous time step. We prove that this particular extension is indeed guaranteed to identify interaction delays between two coupled systems and is the only relevant option in keeping with Wiener’s principle of causality. We demonstrate the performance of our approach in detecting interaction delays on finite data by numerical simulations of stochastic and deterministic processes, as well as on local field potential recordings. We also show the ability of the extended transfer entropy to detect the presence of multiple delays, as well as feedback loops. While evaluated on neuroscience data, we expect the estimator to be useful in other fields dealing with network dynamics. PMID:23468850

  15. Delayed-onset chloroquine retinopathy.

    PubMed Central

    Ehrenfeld, M; Nesher, R; Merin, S

    1986-01-01

    Delayed-onset chloroquine retinopathy was diagnosed in a patient seven years after cessation of treatment by a total dose of 730 g of chloroquine for rheumatoid arthritis. Visual functions continued to deteriorate after the diagnosis. Periodic examinations by ophthalmoscopy and by functional tests such as EOG and visual fields should be continued in patients at risk of delayed-onset chloroquine retinopathy after discontinuance of the drug. PMID:3964626

  16. Tunable silicon CROW delay lines

    NASA Astrophysics Data System (ADS)

    Morichetti, Francesco; Canciamilla, Antonio; Torregiani, Matteo; Ferrari, Carlo; Melloni, Andrea; Martinelli, Mario

    2010-05-01

    Tunable coupled resonator optical waveguides (CROWs) are powerful and versatile devices that can be used to dynamically control the delay of optical data streams on chip. In this contribution we show that CROW delay lines fabricated on a silicon on insulator (SOI) platform are suitable for applications in the emerging scenario of optical systems at 100 Gbit/s. Issues concerning technology, design, limits and applications of SOI CROWs are discussed. The performances of silicon CROW delay lines activated by thermal tuning are compared to those of glass CROW in terms of power consumption, thermal crosstalk and reconfiguration speed. The continuous delay of 10-ps long optical pulses by 8 bit length is demonstrated by using a silicon CROW with a bandwidth of 87 GHz and made of 12 RRs. At 100 Gbit/s this structure provides comparable figures of merit (fractional delay of 0.75 bit/RR and fractional loss of 0.7 dB per bit-delay) of state-of-the art glass CROW operating at 10 Gbit/s, yet the area of the latter being three order of magnitude larger. The compatibility of silicon CROW with the emerging 100 Gbit/s systems is demonstrated by showing error-free phase-preserving propagation of a 100 Gbit/s return-to-zero (RZ) polarization-division-multiplexing (PolDM) differential quaternary phase shit keying (DQPSK) signal dynamically delayed by the CROW. It is also demonstrated that a silicon CROW can be used in a PolDM system to introduce a polarization selective delay in order to optimize the time interleaving of the two orthogonally polarized data streams.

  17. Measuring information-transfer delays.

    PubMed

    Wibral, Michael; Pampu, Nicolae; Priesemann, Viola; Siebenhühner, Felix; Seiwert, Hannes; Lindner, Michael; Lizier, Joseph T; Vicente, Raul

    2013-01-01

    In complex networks such as gene networks, traffic systems or brain circuits it is important to understand how long it takes for the different parts of the network to effectively influence one another. In the brain, for example, axonal delays between brain areas can amount to several tens of milliseconds, adding an intrinsic component to any timing-based processing of information. Inferring neural interaction delays is thus needed to interpret the information transfer revealed by any analysis of directed interactions across brain structures. However, a robust estimation of interaction delays from neural activity faces several challenges if modeling assumptions on interaction mechanisms are wrong or cannot be made. Here, we propose a robust estimator for neuronal interaction delays rooted in an information-theoretic framework, which allows a model-free exploration of interactions. In particular, we extend transfer entropy to account for delayed source-target interactions, while crucially retaining the conditioning on the embedded target state at the immediately previous time step. We prove that this particular extension is indeed guaranteed to identify interaction delays between two coupled systems and is the only relevant option in keeping with Wiener's principle of causality. We demonstrate the performance of our approach in detecting interaction delays on finite data by numerical simulations of stochastic and deterministic processes, as well as on local field potential recordings. We also show the ability of the extended transfer entropy to detect the presence of multiple delays, as well as feedback loops. While evaluated on neuroscience data, we expect the estimator to be useful in other fields dealing with network dynamics. PMID:23468850

  18. Basin stability in delayed dynamics

    PubMed Central

    Leng, Siyang; Lin, Wei; Kurths, Jürgen

    2016-01-01

    Basin stability (BS) is a universal concept for complex systems studies, which focuses on the volume of the basin of attraction instead of the traditional linearization-based approach. It has a lot of applications in real-world systems especially in dynamical systems with a phenomenon of multi-stability, which is even more ubiquitous in delayed dynamics such as the firing neurons, the climatological processes, and the power grids. Due to the infinite dimensional property of the space for the initial values, how to properly define the basin’s volume for delayed dynamics remains a fundamental problem. We propose here a technique which projects the infinite dimensional initial state space to a finite-dimensional Euclidean space by expanding the initial function along with different orthogonal or nonorthogonal basis. A generalized concept of basin’s volume in delayed dynamics and a highly practicable calculating algorithm with a cross-validation procedure are provided to numerically estimate the basin of attraction in delayed dynamics. We show potential applicabilities of this approach by applying it to study several representative systems of biological or/and physical significance, including the delayed Hopfield neuronal model with multistability and delayed complex networks with synchronization dynamics. PMID:26907568

  19. Basin stability in delayed dynamics

    NASA Astrophysics Data System (ADS)

    Leng, Siyang; Lin, Wei; Kurths, Jürgen

    2016-02-01

    Basin stability (BS) is a universal concept for complex systems studies, which focuses on the volume of the basin of attraction instead of the traditional linearization-based approach. It has a lot of applications in real-world systems especially in dynamical systems with a phenomenon of multi-stability, which is even more ubiquitous in delayed dynamics such as the firing neurons, the climatological processes, and the power grids. Due to the infinite dimensional property of the space for the initial values, how to properly define the basin’s volume for delayed dynamics remains a fundamental problem. We propose here a technique which projects the infinite dimensional initial state space to a finite-dimensional Euclidean space by expanding the initial function along with different orthogonal or nonorthogonal basis. A generalized concept of basin’s volume in delayed dynamics and a highly practicable calculating algorithm with a cross-validation procedure are provided to numerically estimate the basin of attraction in delayed dynamics. We show potential applicabilities of this approach by applying it to study several representative systems of biological or/and physical significance, including the delayed Hopfield neuronal model with multistability and delayed complex networks with synchronization dynamics.

  20. Strongly correlated surface states

    NASA Astrophysics Data System (ADS)

    Alexandrov, Victor A.

    Everything has an edge. However trivial, this phrase has dominated theoretical condensed matter in the past half a decade. Prior to that, questions involving the edge considered to be more of an engineering problem rather than a one of fundamental science: it seemed self-evident that every edge is different. However, recent advances proved that many surface properties enjoy a certain universality, and moreover, are 'topologically' protected. In this thesis I discuss a selected range of problems that bring together topological properties of surface states and strong interactions. Strong interactions alone can lead to a wide spectrum of emergent phenomena: from high temperature superconductivity to unconventional magnetic ordering; interactions can change the properties of particles, from heavy electrons to fractional charges. It is a unique challenge to bring these two topics together. The thesis begins by describing a family of methods and models with interactions so high that electrons effectively disappear as particles and new bound states arise. By invoking the AdS/CFT correspondence we can mimic the physical systems of interest as living on the surface of a higher dimensional universe with a black hole. In a specific example we investigate the properties of the surface states and find helical spin structure of emerged particles. The thesis proceeds from helical particles on the surface of black hole to a surface of samarium hexaboride: an f-electron material with localized magnetic moments at every site. Interactions between electrons in the bulk lead to insulating behavior, but the surfaces found to be conducting. This observation motivated an extensive research: weather the origin of conduction is of a topological nature. Among our main results, we confirm theoretically the topological properties of SmB6; introduce a new framework to address similar questions for this type of insulators, called Kondo insulators. Most notably we introduce the idea of Kondo

  1. Kinematics of Strong Discontinuities

    NASA Technical Reports Server (NTRS)

    Peterson, K.; Nguyen, G.; Sulsky, D.

    2006-01-01

    Synthetic Aperture Radar (SAR) provides a detailed view of the Arctic ice cover. When processed with the RADARSAT Geophysical Processor System (RGPS), it provides estimates of sea ice motion and deformation over large regions of the Arctic for extended periods of time. The deformation is dominated by the appearance of linear kinematic features that have been associated with the presence of leads. The RGPS deformation products are based on the assumption that the displacement and velocity are smooth functions of the spatial coordinates. However, if the dominant deformation of multiyear ice results from the opening, closing and shearing of leads, then the displacement and velocity can be discontinuous. This presentation discusses the kinematics associated with strong discontinuities that describe possible jumps in displacement or velocity. Ice motion from SAR data are analyzed using this framework. It is assumed that RGPS cells deform due to the presence of a lead. The lead orientation is calculated to optimally account for the observed deformation. It is shown that almost all observed deformation can be represented by lead opening and shearing. The procedure used to reprocess motion data to account for leads will be described and applied to regions of the Beaufort Sea. The procedure not only provides a new view of ice deformation, it can be used to obtain information about the presence of leads for initialization and/or validation of numerical simulations.

  2. Strong-interaction nonuniversality

    SciTech Connect

    Volkas, R. R.; Foot, R.; He, X.; Joshi, G. C.

    1989-07-01

    The universal QCD color theory is extended to an SU(3)/sub 1//direct product/SU(3)/sub 2//direct product/SU(3)/sub 3/ gauge theory, where quarks of the /ital i/th generation transform as triplets under SU(3)/sub /ital i// and singlets under the other two factors. The usual color group is then identified with the diagonal subgroup, which remains exact after symmetry breaking. The gauge bosons associated with the 16 broken generators then form two massive octets under ordinary color. The interactions between quarks and these heavy gluonlike particles are explicitly nonuniversal and thus an exploration of their physical implications allows us to shed light on the fundamental issue of strong-interaction universality. Nonuniversality and weak flavor mixing are shown to generate heavy-gluon-induced flavor-changing neutral currents. The phenomenology of these processes is studied, as they provide the major experimental constraint on the extended theory. Three symmetry-breaking scenarios are presented. The first has color breaking occurring at the weak scale, while the second and third divorce the two scales. The third model has the interesting feature of radiatively induced off-diagonal Kobayashi-Maskawa matrix elements.

  3. Foreshocks of strong earthquakes

    NASA Astrophysics Data System (ADS)

    Guglielmi, A. V.; Sobisevich, L. E.; Sobisevich, A. L.; Lavrov, I. P.

    2014-07-01

    The specific enhancement of ultra-low-frequency (ULF) electromagnetic oscillations a few hours prior to the strong earthquakes, which was previously mentioned in the literature, motivated us to search for the distinctive features of the mechanical (foreshock) activity of the Earth's crust in the epicentral zones of the future earthquakes. Activation of the foreshocks three hours before the main shock is revealed, which is roughly similar to the enhancement of the specific electromagnetic ULF emission. It is hypothesized that the round-the-world seismic echo signals from the earthquakes, which form the peak of energy release 2 h 50 min before the main events, act as the triggers of the main shocks due to the cumulative action of the surface waves converging to the epicenter. It is established that the frequency of the fluctuations in the foreshock activity decreases at the final stages of the preparation of the main shocks, which probably testifies to the so-called mode softening at the approach of the failure point according to the catastrophe theory.

  4. Prediction of Weather Related Center Delays

    NASA Technical Reports Server (NTRS)

    Deepak, Kulkarni; Banavar, Sridhar

    2008-01-01

    This paper presents results of an initial study of relations between national delay, center level delays and weather. The results presented in the paper indicate: (a) the methodology used for estimating the delay at the national level can be extended to estimate delays caused by a center and delays experienced by a center, (b)delays caused by a center can be predicted using that center's Weather Impacted Traffic Index (WITI) whereas delays experienced by a center are best predicted using WITI of that center and that of a few prominent centers (c) there is differential impact of weather of different centers on center delays.

  5. Delay Independent Criterion for Multiple Time-delay Systems

    NASA Astrophysics Data System (ADS)

    Chang, C. J.; Liu, K. F. R.; Yeh, K.; Chen, C. W.; Chung, P. Y.

    Based on the fuzzy Lyapunov method, this work addresses the stability conditions for nonlinear systems with multiple time delays to ensure the stability of building structure control systems. The delay independent conditions are derived via the traditional Lyapunov and fuzzy Lyapunov methods for multiple time-delay systems as approximated by the Tagagi-Sugeno (T-S) fuzzy model. The fuzzy Lyapunov function is defined as a fuzzy blending of quadratic Lyapunov functions. A parallel distributed compensation (PDC) scheme is utilized to construct a global fuzzy logic control (FLC) by blending all linear local state feedback controllers in the controller design procedure. Furthermore, the H infinity performance and robustness of the design for modeling errors also need to be considered in the stability conditions.

  6. On the linearity of cross-correlation delay times

    NASA Astrophysics Data System (ADS)

    Mercerat, E. D.; Nolet, G.

    2012-12-01

    major contributor to deviation from linearity. The strong velocity contrast of 10% and the regularity of the anomalous structure generate strong reverberations. The test thus provides a worst-case scenario. The results scale up to regional (upper mantle) seismology if times and distances are multiplied by 10(4) . We conclude that in all but the most extreme cases, P-wave delay times depend quasi-linearly on the model perturbations.

  7. Treatment delay in rectal cancer.

    PubMed

    Law, C W; Roslani, A C; Ng, L L C

    2009-06-01

    Early diagnosis of rectal cancer is important for prompt treatment and better outcome. Little data exists for comparison or to set standards. The primary objective of this study is to identify factors resulting in delays in treatment of rectal cancer, the correlation between the disease stage and diagnosis waiting time, treatment waiting time and duration of symptoms. A five year retrospective audit was undertaken in University of Malaya Medical Centre (UMMC). There were 137 patients recruited and the median time to diagnosis was nine days after the first UMMC Surgical Unit consultation with a mean of 18.7 days. Some 11% had to wait more than four weeks for diagnosis. The median time from confirmation of diagnosis to surgery was 11 days with a mean of 18.6 days. Sixty-two percent of patients were operated upon within two weeks of diagnosis and more than 88% by four weeks. However, 10% of them had delayed surgery done four weeks after diagnosis. Long colonoscopy waiting time was the main cause for delay in diagnosis while delay in staging CTs were the main reason for treatment delays. PMID:20058579

  8. Adaptation to delayed auditory feedback

    NASA Technical Reports Server (NTRS)

    Katz, D. I.; Lackner, J. R.

    1977-01-01

    Delayed auditory feedback disrupts the production of speech, causing an increase in speech duration as well as many articulatory errors. To determine whether prolonged exposure to delayed auditory feedback (DAF) leads to adaptive compensations in speech production, 10 subjects were exposed in separate experimental sessions to both incremental and constant-delay exposure conditions. Significant adaptation occurred for syntactically structured stimuli in the form of increased speaking rates. After DAF was removed, aftereffects were apparent for all stimulus types in terms of increased speech rates. A carry-over effect from the first to the second experimental session was evident as long as 29 days after the first session. The use of strategies to overcome DAF and the differences between adaptation to DAF and adaptation to visual rearrangement are discussed.

  9. UWB delay and multiply receiver

    DOEpatents

    Dallum, Gregory E.; Pratt, Garth C.; Haugen, Peter C.; Romero, Carlos E.

    2013-09-10

    An ultra-wideband (UWB) delay and multiply receiver is formed of a receive antenna; a variable gain attenuator connected to the receive antenna; a signal splitter connected to the variable gain attenuator; a multiplier having one input connected to an undelayed signal from the signal splitter and another input connected to a delayed signal from the signal splitter, the delay between the splitter signals being equal to the spacing between pulses from a transmitter whose pulses are being received by the receive antenna; a peak detection circuit connected to the output of the multiplier and connected to the variable gain attenuator to control the variable gain attenuator to maintain a constant amplitude output from the multiplier; and a digital output circuit connected to the output of the multiplier.

  10. 49 CFR 236.563 - Delay time.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Delay time. 236.563 Section 236.563 Transportation... Cab Signal Systems Rules and Instructions; Locomotives § 236.563 Delay time. Delay time of automatic... requirements of § 236.24 shall take into consideration the delay time....

  11. 49 CFR 236.563 - Delay time.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Delay time. 236.563 Section 236.563 Transportation... Cab Signal Systems Rules and Instructions; Locomotives § 236.563 Delay time. Delay time of automatic... requirements of § 236.24 shall take into consideration the delay time....

  12. 49 CFR 236.563 - Delay time.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Delay time. 236.563 Section 236.563 Transportation... Cab Signal Systems Rules and Instructions; Locomotives § 236.563 Delay time. Delay time of automatic... requirements of § 236.24 shall take into consideration the delay time....

  13. 49 CFR 236.563 - Delay time.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Delay time. 236.563 Section 236.563 Transportation... Cab Signal Systems Rules and Instructions; Locomotives § 236.563 Delay time. Delay time of automatic... requirements of § 236.24 shall take into consideration the delay time....

  14. 49 CFR 236.563 - Delay time.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Delay time. 236.563 Section 236.563 Transportation... Cab Signal Systems Rules and Instructions; Locomotives § 236.563 Delay time. Delay time of automatic... requirements of § 236.24 shall take into consideration the delay time....

  15. Variable Delay Testing Using ONE

    NASA Technical Reports Server (NTRS)

    Ishac, Joseph

    2002-01-01

    This paper investigates the effect of long and changing propagation delays on the performance of TCP file transfers. Tests are performed with machines that emulate communication from a low/medium-earth satellite to Earth by way of a geosynchronous satellite. As a result of these tests, we find that TCP is fairly robust to varying delays given a high enough TCP timer granularity. However, performance degrades noticeably for larger file transfers when a finer timer granularity is used. Such results have also been observed in previous simulations by other researchers, and thus, this work serves as an extension of those results.

  16. Incentives help delay marriage among Bangladeshi girls.

    PubMed

    2000-06-01

    In Bangladesh, especially in the rural areas, education has been affordable only for the wealthy. In view of such a situation, the Bangladesh government instituted two incentive programs. One scheme provides wheat to parents of poor primary school boys and girls, and the other offers scholarship money to female secondary school students. Both programs eliminate school fees and provide free books. Aside from the above, a nongovernmental organization, Bangladesh Rural Advancement Committee, administered another program for primary-school students that also provides books and stationery, as well as eliminates fees. This paper assessed the effects of these programs on various aspects of the boys¿ and girls¿ lives. Overall, findings showed that the three programs created significant influence on increasing the number of children who were attending a grade appropriate for their age, although impacts on the number of hours spent in school activities are different. With shorter hours spent in school, depending on grade, children still had the time to make significant contributions to the family economy. Finally, the research shows that the secondary school scholarships had an immediate effect in delaying marriage. If sustained, these delays can have considerable long-term implications for women's status, as early marriages have long been strongly associated with gender inequality. PMID:12296253

  17. Transient Heat Conduction in Strongly Correlated Systems

    NASA Astrophysics Data System (ADS)

    Aghjayan, Rita; Luniewski, Arthur; Walczak, Kamil; Nanoscale Physics Division Team

    2015-03-01

    We analyze heat transport carried by electrons via quantum dots, modeled as strongly-correlated systems with discrete spectrum of available energy levels, which couple to two heat reservoirs of different temperatures. Our computational method for the electronic heat flux is based on the density matrix formalism, while the transition rates between particular quantum states are determined within the Fermi's golden rule. By taking into consideration the non-steady-state solutions for probabilities, we examine the influence of initial conductions and contact-induced time delays onto the rapid thermal switching response of the quantum system under investigation. Specifically, we use several different models for quantum dot, where the Zeeman splitting, Coulomb blockade, and the concept of dark-state are explicitly included. A special attention is devoted to thermal memory effects and the relationship between all the quantum transport expressions and the hyperbolic Cattaneo-Vernotte equation. This research is supported by Pace University Start-up Grant.

  18. Delay discounting of different commodities II: confirmatory analyses.

    PubMed

    Weatherly, Jeffrey N; Terrell, Heather K

    2011-01-01

    Delay discounting occurs when individuals are increasingly willing to accept less than the full amount of something to receive it immediately as the delay to the full amount increases. Previous research has reported different "domains" of commodities, with discounting in one domain not being informative about discounting in another. In the present study, 283 participants completed a delay-discounting task with 1 of 2 sets of 5 commodities identical to those used in previous research (Weatherly, Terrell, & Derenne, 2010). Confirmatory factor analyses determined that the observed discounting conformed to previously reported domains. Also replicated was finding that discounting differs both as a function of commodity and how the commodity is framed. These results provide strong support for the idea that temporal decisions made about certain consequences may not necessarily be informative about how an individual will make decisions about other consequences. Also, the framing of the decision can significantly influence observed levels of discounting, potentially clouding interpretation. PMID:21404948

  19. Persistence in nonautonomous predator-prey systems with infinite delays

    NASA Astrophysics Data System (ADS)

    Teng, Zhidong; Rehim, Mehbuba

    2006-12-01

    This paper studies the general nonautonomous predator-prey Lotka-Volterra systems with infinite delays. The sufficient and necessary conditions of integrable form on the permanence and persistence of species are established. A very interesting and important property of two-species predator-prey systems is discovered, that is, the permanence of species and the existence of a persistent solution are each other equivalent. Particularly, for the periodic system with delays, applying these results, the sufficient and necessary conditions on the permanence and the existence of positive periodic solutions are obtained. Some well-known results on the nondelayed periodic predator-prey Lotka-Volterra systems are strongly improved and extended to the delayed case.

  20. Coherence and quasistable states in a strong infrared field

    NASA Astrophysics Data System (ADS)

    Zhong, Changchun; Robicheaux, F.

    2016-03-01

    We study the quasistability of UV-pulse-train-excited H atoms in a strong infrared (IR) laser as a function of the phase delay of the UV pulse train relative to the IR laser. The UV pulse train contains two frequency components. When the two components have frequencies separated by two IR photons, the population of surviving electrons is modulated by up to ten percent. When electrons are excited to right above or below the threshold, the survival probabilities have inverted phase delay dependence, which can be explained classically. When the two frequencies are one IR photon apart, the angular symmetry of the quasistable electrons is broken, and the asymmetry is also controlled by the phase delay. The asymmetrical distribution can be observed while the IR is on and smoothly evolves to a nonzero asymmetry that only weakly depends on the duration of the IR field.

  1. Local Effects of Delayed Food

    ERIC Educational Resources Information Center

    Davison, Michael; Baum, William M.

    2007-01-01

    Five pigeons were trained on a procedure in which seven concurrent variable-interval schedules arranged seven different food-rate ratios in random sequence in each session. Each of these components lasted for 10 response-produced food deliveries, and components were separated by 10-s blackouts. We varied delays to food (signaled by blackout)…

  2. Delayed School Entry in Uganda

    ERIC Educational Resources Information Center

    Moyi, Peter

    2011-01-01

    Since 1997 Uganda has seen a large increase in school enrolment. Despite this increased enrolment, universal education has remained elusive. Many children enrol in school, but not at the recommended age, and they drop out before completing school. This article focuses on one of these problems--delayed school entry. What household factors are…

  3. Synchronization of time-delayed chemically coupled burst-spiking neurons with correlated noises.

    PubMed

    Zhang, X; Yang, J; Wu, F P; Wu, W J; Jiang, M; Chen, L; Wang, H J; Qi, G X; Huang, H B

    2014-06-01

    Synchronization of two time-delayed chemically coupled neurons with burst-spiking states is studied. Different from the previous study by N. Buric et al. (Phys. Rev. E 78, 036211 (2008)), it is found that exactly synchronous burst-spiking dynamics can occur for small coupling strengths and time delays. The results are confirmed by common time delays and non-equal time delays. When common noise is added to the two neurons, synchronization is enhanced as noise strength is increased. But the results are different for larger time delay and smaller time delay. When noises are correlated, it is found that only strong noises with large correlation coefficient can induce exact synchronization. Even one percent of independent noises can influence synchronization much. PMID:24965152

  4. Measurement of Gravitational Lens Time Delays with LSST (SULI Paper)

    SciTech Connect

    Kirkby, Lowry Anna; /Oxford U. /SLAC

    2006-01-04

    The proposed Large Synoptic Survey Telescope will be the first to explore multiple dark energy probes simultaneously, including baryon acoustic oscillations, weak lensing, and strong gravitational lensing. The large data sample, covering the entire visible sky every few nights, will allow an unprecedented survey of deep supernova sources and their lensed images. The latter have not yet been observed. Notably, LSST will measure the time delays between different strong-lensed images of the same supernova. This will provide a unique probe of dark matter, dark energy, and the expansion rate of the Universe. By simulating LSST observations under realistic conditions, we determined the time delay precision of multiple images from a representative strong-lensed Type Ia supernova. The output of the simulation was a set of light curves according to field and filter, which were subsequently analyzed to determine the experimental time delays. We find that a time delay precision of better then 10% can be achieved under suitable conditions. Firstly, a minimum observed peak-magnitude of 22 is required for the lensed image, corresponding to an intrinsic source magnitude of about 24. The number of such supernova sources expected for LSST is under investigation, but it could amount to several thousand. Secondly, a minimum of about 50 visits per field is required, and, moreover, these visits must be evenly distributed over the duration of the event. The visit frequency should be approximately once per week, or better. Thirdly, the sky brightness should be below 21 magnitude arcsec{sup -2} to allow sufficient sensitivity to distance sources. Under the nominal LSST visiting schedule and field conditions, 15% of all fields satisfy these criteria, and allow time delay measurements of better than 10% precision. This performance can be further improved by fitting the predicted supernova light curves to the observations, rather than using the simple weighted mean as in the present study

  5. Time-delay cosmography: increased leverage with angular diameter distances

    NASA Astrophysics Data System (ADS)

    Jee, I.; Komatsu, E.; Suyu, S. H.; Huterer, D.

    2016-04-01

    Strong lensing time-delay systems constrain cosmological parameters via the so-called time-delay distance and the angular diameter distance to the lens. In previous studies, only the former information was used in forecasting cosmographic constraints. In this paper, we show that the cosmological constraints improve significantly when the latter information is also included. Specifically, the angular diameter distance plays a crucial role in breaking the degeneracy between the curvature of the Universe and the time-varying equation of state of dark energy. Using a mock sample of 55 bright quadruple lens systems based on expectations for ongoing/future imaging surveys, we find that adding the angular diameter distance information to the time-delay distance information and the Planck's measurements of the cosmic microwave background anisotropies improves the constraint on the constant equation of state by 30%, on the time variation in the equation of state by a factor of two, and on the Hubble constant in the flat ΛCDM model by a factor of two. Therefore, previous forecasts for the statistical power of time-delay systems were overly pessimistic, i.e., time-delay systems are more powerful than previously appreciated.

  6. Cortical activation during delay discounting in abstinent methamphetamine dependent individuals

    PubMed Central

    Schwartz, Daniel L.; Huckans, Marilyn S.; McFarland, Bentson H.; Meiri, Gal; Stevens, Alexander A.; Mitchell, Suzanne H.

    2010-01-01

    Background Methamphetamine (MA)-dependent individuals prefer smaller immediate over larger delayed rewards in delay discounting (DD) tasks. Human and animal data implicate ventral (amygdala, ventral striatum, ventrolateral prefrontal cortex insula) and dorsal (dorsolateral prefrontal cortex, dorsal anterior cingulate cortex and posterior parietal cortex) systems in DD decisions. The ventral system is hypothesized to respond to the salience and immediacy of rewards while the dorsal system is implicated in the process of comparison and choice. Methods We used functional Magnetic Resonance Imaging to probe the neural correlates of DD in 19 recently abstinent MA-dependent patients and 17 age- and gender-matched controls. Results Hard DD choices were associated with greatest activation in bilateral middle cingulate, posterior parietal cortex (PPC), and the right rostral insula. Control subjects showed more activation than MA patients bilaterally in the precuneus and in the right caudate nucleus, anterior cingulate cortex (ACC), and dorsolateral prefrontal cortex (DLPFC). Magnitude of discounting was correlated with activity in the amygdala, DLPFC, posterior cingulate cortex and PPC. Conclusions Our findings were consistent with a model wherein dorsal cognitive systems modulate the neural response of ventral regions. Patients addicted to MA, who strongly prefer smaller immediate over larger delayed rewards, activate the dorsal cognitive control system in order to overcome their preference. Activation of the amygdala during choice of delayed rewards was associated with a greater degree of discounting, suggesting that heavily discounting MA-dependent individuals may be more responsive to the negative salience of delayed rewards than controls. PMID:18685833

  7. Delayed Neutron and Delayed Photon Characteristics from Photofission of Actinides

    SciTech Connect

    Dore, D.; Berthoumieux, E.; Leprince, A.; Ridikas, D.

    2011-12-13

    Delayed neutron (DN) and delayed photon (DP) emissions from photofission reactions play an important role for applications involving nuclear material detection and characterization. To provide new, accurate, basic nuclear data for evaluations and data libraries, an experimental programme of DN and DP measurements has been undertaken for actinides with bremsstrahlung endpoint energy in the giant resonance region ({approx}15 MeV). In this paper, the experimental setup and the data analysis method will be described. Experimental results for DN and DP characteristics will be presented for {sup 232}Th, {sup 235,238}U, {sup 237}Np, and {sup 239}Pu. Finally, an example of an application to study the contents of nuclear waste packages will be briefly discussed.

  8. Choice, changing over, and reinforcement delays.

    PubMed Central

    Shahan, T A; Lattal, K A

    2000-01-01

    In three experiments, pigeons were used to examine the independent effects of two normally confounded delays to reinforcement associated with changing between concurrently available variable-interval schedules of reinforcement. In Experiments 1 and 2, combinations of changeover-delay durations and fixed-interval travel requirements were arranged in a changeover-key procedure. The delay from a changeover-produced stimulus change to a reinforcer was varied while the delay between the last response on one alternative and a reinforcer on the other (the total obtained delay) was held constant. Changeover rates decreased as a negative power function of the total obtained delay. The delay between a changeover-produced stimulus change had a small and inconsistent effect on changeover rates. In Experiment 3, changeover delays and fixed-interval travel requirements were arranged independently. Changeover rates decreased as a negative power function of the total obtained delay despite variations in the delay from a change in stimulus conditions to a reinforcer. Periods of high-rate responding following a changeover, however, were higher near the end of the delay from a change in stimulus conditions to a reinforcer. The results of these experiments suggest that the effects of changeover delays and travel requirements primarily result from changes in the delay between a response at one alternative and a reinforcer at the other, but the pattern of responding immediately after a changeover depends on the delay from a changeover-produced change in stimulus conditions to a reinforcer. PMID:11218228

  9. Delay discounting of cocaine by rhesus monkeys.

    PubMed

    Woolverton, William L; Myerson, Joel; Green, Leonard

    2007-06-01

    The present, subjective value of a reinforcer typically decreases as a function of the delay to its receipt, a phenomenon termed delay discounting. Delay discounting, which is assumed to reflect impulsivity, is hypothesized to play an important role in drug abuse. The present study examined delay discounting of cocaine injections by rhesus monkeys. Subjects were studied on a discrete-trials task in which they chose between 2 doses of cocaine: a smaller, immediate dose and a larger, delayed dose. The immediate dose varied between 0.012 and 0.4 mg/kg/injection, whereas the delayed dose was always 0.2 mg/kg/injection and was delivered after a delay that varied between 0 and 300 s in different conditions. At each delay, the point at which a monkey chose the immediate and delayed doses equally often (i.e., the ED50) provided a measure of the present, subjective value of the delayed dose. Dose-response functions for the immediate dose shifted to the left as delay increased. The amount of the immediate dose predicted to be equal in subjective value to the delayed dose decreased as a function of the delay, and hyperbolic discounting functions provided good fits to the data (median R(2)=.86). The current approach may provide the basis for an animal model of the effect of delay on the subjective value of drugs of abuse. PMID:17563210

  10. Delaying mitotic exit downregulates FLIP expression and strongly sensitizes tumor cells to TRAIL.

    PubMed

    Sánchez-Pérez, T; Medema, R H; López-Rivas, A

    2015-01-29

    Many of the current antitumor therapeutic strategies are based on the perturbation of the cell cycle, especially during mitosis. Antimitotic drugs trigger mitotic checkpoint activation, mitotic arrest and eventually cell death. However, mitotic slippage represents a major mechanism of resistance to these treatments. In an attempt to circumvent the process of slippage, targeting mitotic exit has been proposed as a better strategy to kill tumor cells. In this study, we show that treatments that induce mitotic checkpoint activation and mitotic arrest downregulate FLICE-like inhibitory protein (FLIP) levels and sensitize several tumor cell lines to TRAIL (tumor necrosis factor-related apoptosis-inducing ligand)-induced apoptosis. Interestingly, we also demonstrate that in absence of mitotic checkpoint activation, mitotic arrest induced either by Cdc20 knockdown or overexpression of nondegradable cyclin B is sufficient to induce both FLIP downregulation and sensitivity to TRAIL. In summary, our data suggest that a combination of antimitotic drugs targeting cyclin B degradation and TRAIL might prevent mitotic slippage and allow tumor cells to reach the threshold for apoptosis induction, thereby facilitating tumor suppression. PMID:24488010

  11. Time delay and distance measurement

    NASA Technical Reports Server (NTRS)

    Abshire, James B. (Inventor); Sun, Xiaoli (Inventor)

    2011-01-01

    A method for measuring time delay and distance may include providing an electromagnetic radiation carrier frequency and modulating one or more of amplitude, phase, frequency, polarization, and pointing angle of the carrier frequency with a return to zero (RZ) pseudo random noise (PN) code. The RZ PN code may have a constant bit period and a pulse duration that is less than the bit period. A receiver may detect the electromagnetic radiation and calculate the scattering profile versus time (or range) by computing a cross correlation function between the recorded received signal and a three-state RZ PN code kernel in the receiver. The method also may be used for pulse delay time (i.e., PPM) communications.

  12. Synchronization by small time delays

    NASA Astrophysics Data System (ADS)

    Pruessner, G.; Cheang, S.; Jensen, H. J.

    2015-02-01

    Synchronization is a phenomenon observed in all of the living and in much of the non-living world, for example in the heart beat, Huygens' clocks, the flashing of fireflies and the clapping of audiences. Depending on the number of degrees of freedom involved, different mathematical approaches have been used to describe it, most prominently integrate-and-fire oscillators and the Kuramoto model of coupled oscillators. In the present work, we study a very simple and general system of smoothly evolving oscillators, which continue to interact even in the synchronized state. We find that under very general circumstances, synchronization generically occurs in the presence of a (small) time delay. Strikingly, the synchronization time is inversely proportional to the time delay.

  13. Delay locked loop integrated circuit.

    SciTech Connect

    Brocato, Robert Wesley

    2007-10-01

    This report gives a description of the development of a Delay Locked Loop (DLL) integrated circuit (IC). The DLL was developed and tested as a stand-alone IC test chip to be integrated into a larger application specific integrated circuit (ASIC), the Quadrature Digital Waveform Synthesizer (QDWS). The purpose of the DLL is to provide a digitally programmable delay to enable synchronization between an internal system clock and external peripherals with unknown clock skew. The DLL was designed and fabricated in the IBM 8RF process, a 0.13 {micro}m CMOS process. It was designed to operate with a 300MHz clock and has been tested up to 500MHz.

  14. Method for calcining delayed coke

    SciTech Connect

    Smith, J.H.

    1981-02-17

    Delayed petroleum coke is calcined in an internally-fired vertical shaft kiln. A downwardly-moving bed of green coke is preheated in the top of the kiln by rising combustion gases, then heat soaked at calcining temperatures in the intermediate section of the kiln, and finally cooled by recycle gas moving upwardly from the lower part of the kiln. Partially cooled calcined coke is recovered from the bottom of the kiln.

  15. Delayed recombination and standard rulers

    SciTech Connect

    De Bernardis, Francesco; Melchiorri, Alessandro; Bean, Rachel; Galli, Silvia; Silk, Joseph I.; Verde, Licia

    2009-02-15

    Measurements of baryonic acoustic oscillations (BAOs) in galaxy surveys have been recognized as a powerful tool for constraining dark energy. However, this method relies on the knowledge of the size of the acoustic horizon at recombination derived from cosmic microwave background (CMB) anisotropy measurements. This estimate is typically derived assuming a standard recombination scheme; additional radiation sources can delay recombination altering the cosmic ionization history and the cosmological inferences drawn from CMB and BAO data. In this paper we quantify the effect of delayed recombination on the determination of dark energy parameters from future BAO surveys such as the Baryon Oscillation Spectroscopic Survey and the Wide-Field Multi-Object Spectrograph. We find the impact to be small but still not negligible. In particular, if recombination is nonstandard (to a level still allowed by CMB data), but this is ignored, future surveys may incorrectly suggest the presence of a redshift-dependent dark energy component. On the other hand, in the case of delayed recombination, adding to the analysis one extra parameter describing deviations from standard recombination does not significantly degrade the error bars on dark energy parameters and yields unbiased estimates. This is due to the CMB-BAO complementarity.

  16. 78 FR 43270 - List of Applications Delayed

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ... Pipeline and Hazardous Materials Safety Administration List of Applications Delayed AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), DOT. ACTION: List of applications delayed more than 180... Hazardous Materials Special Permits ] and Approvals, Pipeline and Hazardous Materials Safety...

  17. Language Delays in Toddlers: Information for Parents

    MedlinePlus

    ... Children > Ages & Stages > Toddler > Language Delays in Toddlers: Information for Parents Ages & Stages Listen Español Text Size Email Print Share Language Delays in Toddlers: Information for Parents Page Content Article Body Your baby ...

  18. Delayed/back up antibiotic prescriptions: what do the public think?

    PubMed Central

    McNulty, Cliodna A M; Lecky, Donna M; Hawking, Meredith K D; Quigley, Anna; Butler, Chris C

    2015-01-01

    Objective To describe the general public's understanding, acceptance and use of delayed antibiotics. Design Face to face computer-assisted survey using an Ipsos MORI Capibus survey. Setting Randomly selected households in England using multistage sampling. Respondents A representative sample of 1625 adults aged over 15 years and recruited from household visits in England, using age and gender quotas for each area. Data collection and analysis The survey was undertaken in January 2014. Weights based on gender, age, ethnicity, working status, social grade, housing tenure and Government Office Region corrected for selection biases, so that results are broadly representative of the population. Main outcomes measures Proportion of respondents; understanding the meaning of the term delayed antibiotic prescription and how the strategy is used in general practice; in favour of, or opposed to clinicians offering them a delayed antibiotic; reporting receipt, use and acceptability of delayed antibiotic prescriptions in the past year. Results 17% reported fully understanding the meaning of delayed antibiotic prescription and strategy use in general practice;72% were unaware of the term or strategy; 36–39% were in favour of, and 28–30% opposed to clinicians offering them a delayed antibiotic for throat, urine, ear or chest infections. Half of those who were fully aware of the term and practice were in favour of delayed antibiotics. Women, and older respondents, were more strongly opposed to delayed prescribing. Only 4% of all respondents, and 15% of those prescribed an antibiotic, reported being offered a delayed antibiotic in the last year. Conclusions Wider understanding and acceptance of delayed prescribing may facilitate increased uptake. Further research is needed to determine why groups are so strongly in favour or opposed to delayed prescribing. PMID:26614626

  19. 40 CFR 1500.5 - Reducing delay.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Reducing delay. 1500.5 Section 1500.5 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY PURPOSE, POLICY, AND MANDATE § 1500.5 Reducing delay. Agencies shall reduce delay by: (a) Integrating the NEPA process into early planning (§...

  20. 40 CFR 1500.5 - Reducing delay.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Reducing delay. 1500.5 Section 1500.5 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY PURPOSE, POLICY, AND MANDATE § 1500.5 Reducing delay. Agencies shall reduce delay by: (a) Integrating the NEPA process into early planning (§...

  1. 42 CFR 136a.32 - Delayed implementation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Delayed implementation. 136a.32 Section 136a.32..., DEPARTMENT OF HEALTH AND HUMAN SERVICES INDIAN HEALTH Transition Provisions § 136a.32 Delayed implementation...) During the six month delayed implementation period the former eligibility regulations will apply....

  2. Academic Delay of Gratification and Academic Achievement

    ERIC Educational Resources Information Center

    Bembenutty, Hefer

    2011-01-01

    The ability to delay gratification is the cornerstone of all academic achievement and education. It is by delaying gratification that learners can pursue long-term academic and career goals. In general, "delay of gratification" refers to an individual's ability to forgo immediate rewards for the sake of more valuable ones later (Mischel, 1996).…

  3. Articulatory Preparation in the Delayed Naming Task

    ERIC Educational Resources Information Center

    Kawamoto, Alan H.; Liu, Qiang; Mura, Keith; Sanchez, Adrianna

    2008-01-01

    The assumptions that acoustic onset must follow articulatory onset by a fixed delay and that response execution level processes are always effectively isolated in the delayed naming task were investigated with respect to the issue of articulatory preparation in three experiments. The results of these experiments showed that for the delayed naming…

  4. Contingency Tracking during Unsignaled Delayed Reinforcement

    ERIC Educational Resources Information Center

    Keely, Josue; Feola, Tyler; Lattal, Kennon A.

    2007-01-01

    Three experiments were conducted with rats in which responses on one lever (labeled the functional lever) produced reinforcers after an unsignaled delay period that reset with each response during the delay. Responses on a second, nonfunctional, lever did not initiate delays, but, in the first and third experiments, such responses during the last…

  5. 34 CFR 303.10 - Developmental delay.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 2 2013-07-01 2013-07-01 false Developmental delay. 303.10 Section 303.10 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND... DISABILITIES General Definitions Used in This Part § 303.10 Developmental delay. Developmental delay, when...

  6. 34 CFR 303.10 - Developmental delay.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 2 2014-07-01 2013-07-01 true Developmental delay. 303.10 Section 303.10 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND... DISABILITIES General Definitions Used in This Part § 303.10 Developmental delay. Developmental delay, when...

  7. 34 CFR 303.10 - Developmental delay.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 2 2012-07-01 2012-07-01 false Developmental delay. 303.10 Section 303.10 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND... DISABILITIES General Definitions Used in This Part § 303.10 Developmental delay. Developmental delay, when...

  8. Direct-reading group-delay measurement

    NASA Technical Reports Server (NTRS)

    Trowbridge, D. L.

    1978-01-01

    Technique for measuring modulation signal retardation in microwave components gives direct plot of dependence of delay time on carrier frequency. Recorder sensitivity can be adjusted to give convenient scale factor for group delay. From family of such recordings, it is possible to observe changes in group delay due to temperature, mechanical stress, and other factors.

  9. Nonautonomous Lotka-Volterra Systems with Delays

    NASA Astrophysics Data System (ADS)

    Teng, Zhidong

    2002-03-01

    The paper studies the general nonautonomous Lotka-Volterra multispecies systems with finite delays. The ultimate boundedness, permanence, global attractivity, and existence and uniqueness of strictly positive solutions, positive periodic solutions, and almost periodic solutions are obtained. These results are basically an extension of the known results for nonautonomous Lotka-Volterra multispecies systems without delay to systems with delay.

  10. The French human Salmonella surveillance system: evaluation of timeliness of laboratory reporting and factors associated with delays, 2007 to 2011.

    PubMed

    Jones, G; Le Hello, S; Jourdan-da Silva, N; Vaillant, V; de Valk, H; Weill, Fx; Le Strat, Y

    2014-01-01

    Given the regular occurrence of salmonellosis outbreaks in France, evaluating the timeliness of laboratory reporting is critical for maintaining an effective surveillance system. Laboratory-confirmed human cases of Salmonella infection from whom strains were isolated from 2007 to 2011 in France (n=38,413) were extracted from the surveillance database. Three delay intervals were defined: transport delay (strain isolation, transport from primary laboratory to national reference laboratory), analysis delay (serotyping, reporting) and total reporting delay. We calculated the median delay in days and generated the cumulative delay distribution for each interval. Variables were tested for an association with reporting delay using a multivariable generalised linear model. The median transport and analysis delays were 7 and 6 days respectively (interquartile range (IQR: 6-10 and 4-9 respectively), with a median total reporting delay of 14 days (IQR: 11-19). Timeliness was influenced by various external factors: decreasing serotype frequency, geographical zone of primary laboratory and strain isolation on Sundays were the variables most strongly associated with increased length of delay. The effect of season and day of the week of isolation was highly variable over the study period. Several areas for interventions to shorten delays are identified and discussed for both transport and analysis delays. PMID:24434174

  11. Short Conduction Delays Cause Inhibition Rather than Excitation to Favor Synchrony in Hybrid Neuronal Networks of the Entorhinal Cortex

    PubMed Central

    Fernandez, Fernando R.; White, John A.; Canavier, Carmen C.

    2012-01-01

    How stable synchrony in neuronal networks is sustained in the presence of conduction delays is an open question. The Dynamic Clamp was used to measure phase resetting curves (PRCs) for entorhinal cortical cells, and then to construct networks of two such neurons. PRCs were in general Type I (all advances or all delays) or weakly type II with a small region at early phases with the opposite type of resetting. We used previously developed theoretical methods based on PRCs under the assumption of pulsatile coupling to predict the delays that synchronize these hybrid circuits. For excitatory coupling, synchrony was predicted and observed only with no delay and for delays greater than half a network period that cause each neuron to receive an input late in its firing cycle and almost immediately fire an action potential. Synchronization for these long delays was surprisingly tight and robust to the noise and heterogeneity inherent in a biological system. In contrast to excitatory coupling, inhibitory coupling led to antiphase for no delay, very short delays and delays close to a network period, but to near-synchrony for a wide range of relatively short delays. PRC-based methods show that conduction delays can stabilize synchrony in several ways, including neutralizing a discontinuity introduced by strong inhibition, favoring synchrony in the case of noisy bistability, and avoiding an initial destabilizing region of a weakly type II PRC. PRCs can identify optimal conduction delays favoring synchronization at a given frequency, and also predict robustness to noise and heterogeneity. PMID:22241969

  12. Strong-back safety latch

    SciTech Connect

    DeSantis, G.N.

    1995-03-06

    The calculation decides the integrity of the safety latch that will hold the strong-back to the pump during lifting. The safety latch will be welded to the strong-back and will latch to a 1.5-in. dia cantilever rod welded to the pump baseplate. The static and dynamic analysis shows that the safety latch will hold the strong-back to the pump if the friction clamps fail and the pump become free from the strong-back. Thus, the safety latch will meet the requirements of the Lifting and Rigging Manual for under the hook lifting for static loading; it can withstand shock loads from the strong-back falling 0.25 inch.

  13. BOLD delay times using group delay in sickle cell disease

    NASA Astrophysics Data System (ADS)

    Coloigner, Julie; Vu, Chau; Bush, Adam; Borzage, Matt; Rajagopalan, Vidya; Lepore, Natasha; Wood, John

    2016-03-01

    Sickle cell disease (SCD) is an inherited blood disorder that effects red blood cells, which can lead to vasoocclusion, ischemia and infarct. This disease often results in neurological damage and strokes, leading to morbidity and mortality. Functional Magnetic Resonance Imaging (fMRI) is a non-invasive technique for measuring and mapping the brain activity. Blood Oxygenation Level-Dependent (BOLD) signals contain also information about the neurovascular coupling, vascular reactivity, oxygenation and blood propagation. Temporal relationship between BOLD fluctuations in different parts of the brain provides also a mean to investigate the blood delay information. We used the induced desaturation as a label to profile transit times through different brain areas, reflecting oxygen utilization of tissue. In this study, we aimed to compare blood flow propagation delay times between these patients and healthy subjects in areas vascularized by anterior, middle and posterior cerebral arteries. In a group comparison analysis with control subjects, BOLD changes in these areas were found to be almost simultaneous and shorter in the SCD patients, because of their increased brain blood flow. Secondly, the analysis of a patient with a stenosis on the anterior cerebral artery indicated that signal of the area vascularized by this artery lagged the MCA signal. These findings suggest that sickle cell disease causes blood propagation modifications, and that these changes could be used as a biomarker of vascular damage.

  14. Recent advances of strong-strong beam-beam simulation

    SciTech Connect

    Qiang, Ji; Furman, Miguel A.; Ryne, Robert D.; Fischer, Wolfram; Ohmi,Kazuhito

    2004-09-15

    In this paper, we report on recent advances in strong-strong beam-beam simulation. Numerical methods used in the calculation of the beam-beam forces are reviewed. A new computational method to solve the Poisson equation on nonuniform grid is presented. This method reduces the computational cost by a half compared with the standard FFT based method on uniform grid. It is also more accurate than the standard method for a colliding beam with low transverse aspect ratio. In applications, we present the study of coherent modes with multi-bunch, multi-collision beam-beam interactions at RHIC. We also present the strong-strong simulation of the luminosity evolution at KEKB with and without finite crossing angle.

  15. ADHD and Delay Aversion: The Influence of Non-Temporal Stimulation on Choice for Delayed Rewards

    ERIC Educational Resources Information Center

    Antrop, Inge; Stock, Pieter; Verte, Sylvie; Wiersema, Jan Roelt; Baeyens, Dieter; Roeyers, Herbert

    2006-01-01

    Background: Delay aversion, the motivation to escape or avoid delay, results in preference for small immediate over large delayed rewards. Delay aversion has been proposed as one distinctive psychological process that may underlie the behavioural symptoms and cognitive deficits of attention deficit/hyperactivity disorder (ADHD). Furthermore, the…

  16. Modeling of SAW Delay Lines

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2007-01-01

    Integrated Vehicle Health Monitoring (IVHM) of aerospace vehicles requires rugged sensors having reduced volume, mass, and power that can be used to measure a variety of phenomena. Wireless systems are preferred when retro-fitting sensors onto existing vehicles. Surface Acoustic Wave (SAW) devices are capable of sensing: temperature, pressure, strain, chemical species, mass loading, acceleration, and shear stress. SAW technology is low cost, rugged, lightweight, and extremely low power. To aid in the development of SAW sensors for IVHM applications, a first order model of a SAW Delay line has been created.

  17. Delayed diagnosis of Pendred syndrome.

    PubMed

    Smith, Natalie; U-King-Im, Jean-Marie; Karalliedde, Janaka

    2016-01-01

    We describe a case of a delayed diagnosis of Pendred syndrome. The patient had a history of hearing loss from childhood and presented to the endocrine clinic when aged 32 with an enlarging goitre. The characteristic Mondini deformity was noted on auditory canal MRI scan. Genetic tests confirmed the diagnosis. Pendred syndrome is an autosomal recessive disorder, characterised by congenital sensorineural hearing loss, goitre and impaired iodide organification and can present at any age. We highlight to the general physician the classical features of this syndrome that would aid early diagnosis. PMID:27620717

  18. Photothermally induced delayed tissue death.

    PubMed

    Gordon, Jeffrey M; Shaco-Levy, Ruthy; Feuermann, Daniel; Huleihil, Mahmoud; Mizrahi, Solly

    2006-01-01

    We report pronounced delayed tissue death in photothermal surgery performed on the livers of live healthy rats with highly concentrated sunlight (ultrabright noncoherent light). Exposure times and power levels were selected to produce immediate necroses of the order of hundreds of cubic millimeters. Pathology reveals that lesion volumes increase by up to a factor of 5 within approximately 24 h after surgery, and then stabilize. Islands of viable cells can persist within damaged tissue, in the immediate vicinity of blood vessels, but also necrose within about 48 h. PMID:16822049

  19. Delay test generation for synchronous sequential circuits

    NASA Astrophysics Data System (ADS)

    Devadas, Srinivas

    1989-05-01

    We address the problem of generating tests for delay faults in non-scan synchronous sequential circuits. Delay test generation for sequential circuits is a considerably more difficult problem than delay testing of combinational circuits and has received much less attention. In this paper, we present a method for generating test sequences to detect delay faults in sequential circuits using the stuck-at fault sequential test generator STALLION. The method is complete in that it will generate a delay test sequence for a targeted fault given sufficient CPU time, if such a sequence exists. We term faults for which no delay test sequence exists, under out test methodology, sequentially delay redundant. We describe means of eliminating sequential delay redundancies in logic circuits. We present a partial-scan methodology for enhancing the testability of difficult-to-test of untestable sequential circuits, wherein a small number of flip-flops are selected and made controllable/observable. The selection process guarantees the elimination of all sequential delay redundancies. We show that an intimate relationship exists between state assignment and delay testability of a sequential machine. We describe a state assignment algorithm for the synthesis of sequential machines with maximal delay fault testability. Preliminary experimental results using the test generation, partial-scan and synthesis algorithm are presented.

  20. Precise delay measurement through combinatorial logic

    NASA Technical Reports Server (NTRS)

    Burke, Gary R. (Inventor); Chen, Yuan (Inventor); Sheldon, Douglas J. (Inventor)

    2010-01-01

    A high resolution circuit and method for facilitating precise measurement of on-chip delays for FPGAs for reliability studies. The circuit embeds a pulse generator on an FPGA chip having one or more groups of LUTS (the "LUT delay chain"), also on-chip. The circuit also embeds a pulse width measurement circuit on-chip, and measures the duration of the generated pulse through the delay chain. The pulse width of the output pulse represents the delay through the delay chain without any I/O delay. The pulse width measurement circuit uses an additional asynchronous clock autonomous from the main clock and the FPGA propagation delay can be displayed on a hex display continuously for testing purposes.

  1. Time-delayed feedback in neurosystems.

    PubMed

    Schöll, Eckehard; Hiller, Gerald; Hövel, Philipp; Dahlem, Markus A

    2009-03-28

    The influence of time delay in systems of two coupled excitable neurons is studied in the framework of the FitzHugh-Nagumo model. A time delay can occur in the coupling between neurons or in a self-feedback loop. The stochastic synchronization of instantaneously coupled neurons under the influence of white noise can be deliberately controlled by local time-delayed feedback. By appropriate choice of the delay time, synchronization can be either enhanced or suppressed. In delay-coupled neurons, antiphase oscillations can be induced for sufficiently large delay and coupling strength. The additional application of time-delayed self-feedback leads to complex scenarios of synchronized in-phase or antiphase oscillations, bursting patterns or amplitude death. PMID:19218152

  2. The influences of delay time on the stability of a market model with stochastic volatility

    NASA Astrophysics Data System (ADS)

    Li, Jiang-Cheng; Mei, Dong-Cheng

    2013-02-01

    The effects of the delay time on the stability of a market model are investigated, by using a modified Heston model with a cubic nonlinearity and cross-correlated noise sources. These results indicate that: (i) There is an optimal delay time τo which maximally enhances the stability of the stock price under strong demand elasticity of stock price, and maximally reduces the stability of the stock price under weak demand elasticity of stock price; (ii) The cross correlation coefficient of noises and the delay time play an opposite role on the stability for the case of the delay time <τo and the same role for the case of the delay time >τo. Moreover, the probability density function of the escape time of stock price returns, the probability density function of the returns and the correlation function of the returns are compared with other literatures.

  3. Titanium: light, strong, and white

    USGS Publications Warehouse

    Woodruff, Laurel; Bedinger, George

    2013-01-01

    Titanium (Ti) is a strong silver-gray metal that is highly resistant to corrosion and is chemically inert. It is as strong as steel but 45 percent lighter, and it is twice as strong as aluminum but only 60 percent heavier. Titanium dioxide (TiO2) has a very high refractive index, which means that it has high light-scattering ability. As a result, TiO2 imparts whiteness, opacity, and brightness to many products. ...Because of the unique physical properties of titanium metal and the whiteness provided by TiO2, titanium is now used widely in modern industrial societies.

  4. Time delay and magnification centroid due to gravitational lensing by black holes and naked singularities

    SciTech Connect

    Virbhadra, K. S.; Keeton, C. R.

    2008-06-15

    We model the massive dark object at the center of the Galaxy as a Schwarzschild black hole as well as Janis-Newman-Winicour naked singularities, characterized by the mass and scalar charge parameters, and study gravitational lensing (particularly time delay, magnification centroid, and total magnification) by them. We find that the lensing features are qualitatively similar (though quantitatively different) for Schwarzschild black holes, weakly naked, and marginally strongly naked singularities. However, the lensing characteristics of strongly naked singularities are qualitatively very different from those due to Schwarzschild black holes. The images produced by Schwarzschild black hole lenses and weakly naked and marginally strongly naked singularity lenses always have positive time delays. On the other hand, strongly naked singularity lenses can give rise to images with positive, zero, or negative time delays. In particular, for a large angular source position the direct image (the outermost image on the same side as the source) due to strongly naked singularity lensing always has a negative time delay. We also found that the scalar field decreases the time delay and increases the total magnification of images; this result could have important implications for cosmology. As the Janis-Newman-Winicour metric also describes the exterior gravitational field of a scalar star, naked singularities as well as scalar star lenses, if these exist in nature, will serve as more efficient cosmic telescopes than regular gravitational lenses.

  5. Learning when reward is delayed: a marking hypothesis.

    PubMed

    Lieberman, D A; McIntosh, D C; Thomas, G V

    1979-07-01

    Rats were trained on spatial discriminations in which reward was delayed for 1 min. Experiment 1 tested Lett's hypothesis that responses made in the home cage during the delay interval are less likely to interfere with learning than responses made in the maze. Experimental subjects were transferred to their home cages during the delay interval, and control subjects were picked up but then immediately replaced in the maze. Contrary to Lett's hypothesis, both groups learned. Further experiments suggested that handling following a choice response was the crucial variable in producing learning: No learning occurred when handling was delayed (Experiment 2) or omitted (Experiment 3). One possible explanation for the fact that handling facilitated learning is that it served to mark the preceding choice response in memory so that subjects were then more likely to recall it when subsequently reinforced. In accordance with this interpretation, learning was found to be just as strong when the choice response was followed by an intense light or noise as by handling (Experiment 4). The implication of marking for other phenomena such as avoidance, quasi-reinforcement, and the paradoxical effects of punishment is also discussed. PMID:528888

  6. Delayed recombination and cosmic parameters

    NASA Astrophysics Data System (ADS)

    Galli, Silvia; Bean, Rachel; Melchiorri, Alessandro; Silk, Joseph

    2008-09-01

    Current cosmological constraints from cosmic microwave background anisotropies are typically derived assuming a standard recombination scheme, however additional resonance and ionizing radiation sources can delay recombination, altering the cosmic ionization history and the cosmological inferences drawn from the cosmic microwave background data. We show that for recent observations of the cosmic microwave background anisotropy, from the Wilkinson microwave anisotropy probe satellite mission (WMAP) 5-year survey and from the arcminute cosmology bolometer array receiver experiment, additional resonance radiation is nearly degenerate with variations in the spectral index, ns, and has a marked effect on uncertainties in constraints on the Hubble constant, age of the universe, curvature and the upper bound on the neutrino mass. When a modified recombination scheme is considered, the redshift of recombination is constrained to z*=1078±11, with uncertainties in the measurement weaker by 1 order of magnitude than those obtained under the assumption of standard recombination while constraints on the shift parameter are shifted by 1σ to R=1.734±0.028. From the WMAP5 data we obtain the following constraints on the resonance and ionization sources parameters: γα<0.39 and γi<0.058 at 95% c.l.. Although delayed recombination limits the precision of parameter estimation from the WMAP satellite, we demonstrate that this should not be the case for future, smaller angular scales measurements, such as those by the Planck satellite mission.

  7. PRECISION TIME-DELAY GENERATOR

    DOEpatents

    Carr, B.J.; Peckham, V.D.

    1959-06-16

    A precision time-delay generator circuit with low jitter is described. The first thyratron has a series resonant circuit and a diode which is connected to the second thyratron. The first thyratron is triggered at the begin-ning of a time delay and a capacitor is discharged through the first thyratron and the diode, thereby, triggering the second thyratron. (T.R.H.) l6l9O The instrument described can measure pressures between sea level and 300,000 ft. The pressure- sensing transducer of the instrument is a small cylindrical tube with a thin foil of titanium-tritium fastened around the inside of the tube. Output is a digital signal which can be used for storage or telemetering more conveniently than an analog signal. (W.D.M.) l6l9l An experimental study was made on rolling contacts in the temperature range of 550 to 1000 deg F. Variables such as material composition, hardness, and operating conditions were investigated in a rolling test stand. Ball bearing tests were run to determine the effect of design parameters, bearing materials, lubricants, and operating conditions. (auth)

  8. Cross delay line sensor characterization

    SciTech Connect

    Owens, Israel J; Remelius, Dennis K; Tiee, Joe J; Buck, Steven E; Whittemore, Stephen R; Thompson, David C; Shirey, Robert

    2010-01-01

    There exists a wealth of information in the scientific literature on the physical properties and device characterization procedures for complementary metal oxide semiconductor (CMOS), charge coupled device (CCD) and avalanche photodiode (APD) format detectors. Numerous papers and books have also treated photocathode operation in the context of photomultiplier tube (PMT) operation for either non imaging applications or limited night vision capability. However, much less information has been reported in the literature about the characterization procedures and properties of photocathode detectors with novel cross delay line (XDL) anode structures. These allow one to detect single photons and create images by recording space and time coordinate (X, Y & T) information. In this paper, we report on the physical characteristics and performance of a cross delay line anode sensor with an enhanced near infrared wavelength response photocathode and high dynamic range micro channel plate (MCP) gain (> 10{sup 6}) multiplier stage. Measurement procedures and results including the device dark event rate (DER), pulse height distribution, quantum and electronic device efficiency (QE & DQE) and spatial resolution per effective pixel region in a 25 mm sensor array are presented. The overall knowledge and information obtained from XDL sensor characterization allow us to optimize device performance and assess capability. These device performance properties and capabilities make XDL detectors ideal for remote sensing field applications that require single photon detection, imaging, sub nano-second timing response, high spatial resolution (10's of microns) and large effective image format.

  9. Delayed coker fractionator advanced control

    SciTech Connect

    Jaisinghani, R.; Minter, B. ); Tica, A.; Puglesi, A.; Ojeda, R. )

    1993-08-01

    In a delayed coking process, as coke drum switches are made, rapid changes occur in both the fractionator feed rate and composition. With conventional control, it is not unusual to see long transient behavior of large swings in both quality and flowrates of coker gas oils. This can extract a heavy economic toll, not only in coker operation, but in the operation of downstream units as the upset is propagated. An advanced process control application (APC) was recently implemented on the coker fractionator at the Yacimentos Petroliferos Fiscales (YPF), Lujan de Cuyo Refinery, in Mendoza, Argentina. This coker fractionator control design was unique as it handled two different operating objectives: control of product qualities via tower temperature profile during normal operation and control of gas oil product flow ratio during drum switch. This combination of control objectives in one multivariable predictive control program was achieved by including special logic to decouple the individual tuning requirements. Also, additional logic was included to unambiguously detect and identify drum switch and drum steam out as discrete events within 30 seconds of their actual occurrence. These discrete events were then used as disturbance variables to minimize fractionator transient behavior. As a performance measure, the overhead temperature was controlled within 2 C to 2.5 C of its target, gas oil flows were stabilized during drum switches and steam generation via pump around was maximized. Overall, implementing advanced control for the delayed coker fractionator resulted in substantial benefits from product quality control, product flow control and minimized energy consumption.

  10. Delayed recombination and cosmic parameters

    SciTech Connect

    Galli, Silvia; Melchiorri, Alessandro; Bean, Rachel; Silk, Joseph

    2008-09-15

    Current cosmological constraints from cosmic microwave background anisotropies are typically derived assuming a standard recombination scheme, however additional resonance and ionizing radiation sources can delay recombination, altering the cosmic ionization history and the cosmological inferences drawn from the cosmic microwave background data. We show that for recent observations of the cosmic microwave background anisotropy, from the Wilkinson microwave anisotropy probe satellite mission (WMAP) 5-year survey and from the arcminute cosmology bolometer array receiver experiment, additional resonance radiation is nearly degenerate with variations in the spectral index, n{sub s}, and has a marked effect on uncertainties in constraints on the Hubble constant, age of the universe, curvature and the upper bound on the neutrino mass. When a modified recombination scheme is considered, the redshift of recombination is constrained to z{sub *}=1078{+-}11, with uncertainties in the measurement weaker by 1 order of magnitude than those obtained under the assumption of standard recombination while constraints on the shift parameter are shifted by 1{sigma} to R=1.734{+-}0.028. From the WMAP5 data we obtain the following constraints on the resonance and ionization sources parameters: {epsilon}{sub {alpha}}<0.39 and {epsilon}{sub i}<0.058 at 95% c.l.. Although delayed recombination limits the precision of parameter estimation from the WMAP satellite, we demonstrate that this should not be the case for future, smaller angular scales measurements, such as those by the Planck satellite mission.

  11. Cross delay line sensor characterization

    NASA Astrophysics Data System (ADS)

    Owens, Israel J.; Remelius, Dennis K.; Tiee, Joe J.; Buck, Steven E.; Whittemore, Stephen R.; Thompson, David C.; Shirey, Robert

    2010-04-01

    There exists a wealth of information in the scientific literature on the physical properties and device characterization procedures for complementary metal oxide semiconductor (CMOS), charge coupled device (CCD) and avalanche photodiode (APD) format detectors. Numerous papers and books have also treated photocathode operation in the context of photomultiplier tube (PMT) operation for either non imaging applications or limited night vision capability. However, much less information has been reported in the literature about the characterization procedures and properties of photocathode detectors with novel cross delay line (XDL) anode structures. These allow one to detect single photons and create images by recording space and time coordinate (X, Y & T) information. In this paper, we report on the physical characteristics and performance of a cross delay line anode sensor with an enhanced near infrared wavelength response photocathode and high dynamic range micro channel plate (MCP) gain (> 106 ) multiplier stage. Measurement procedures and results including the device dark event rate (DER), pulse height distribution, quantum and electronic device efficiency (QE & DQE) and spatial resolution per effective pixel region in a 25 mm sensor array are presented. The overall knowledge and information obtained from XDL sensor characterization allow us to optimize device performance and assess capability. These device performance properties and capabilities make XDL detectors ideal for remote sensing field applications that require single photon detection, imaging, sub nano-second timing response, high spatial resolution (10's of microns) and large effective image format.ÿ

  12. Imitation of contrastive lexical stress in children with speech delay

    NASA Astrophysics Data System (ADS)

    Vick, Jennell C.; Moore, Christopher A.

    2005-09-01

    This study examined the relationship between acoustic correlates of stress in trochaic (strong-weak), spondaic (strong-strong), and iambic (weak-strong) nonword bisyllables produced by children (30-50) with normal speech acquisition and children with speech delay. Ratios comparing the acoustic measures (vowel duration, rms, and f0) of the first syllable to the second syllable were calculated to evaluate the extent to which each phonetic parameter was used to mark stress. In addition, a calculation of the variability of jaw movement in each bisyllable was made. Finally, perceptual judgments of accuracy of stress production were made. Analysis of perceptual judgments indicated a robust difference between groups: While both groups of children produced errors in imitating the contrastive lexical stress models (~40%), the children with normal speech acquisition tended to produce trochaic forms in substitution for other stress types, whereas children with speech delay showed no preference for trochees. The relationship between segmental acoustic parameters, kinematic variability, and the ratings of stress by trained listeners will be presented.

  13. Simulating strongly correlated electrons with a strongly interacting Fermi gas

    SciTech Connect

    Thomas, John E.

    2013-05-28

    The quantum many-body physics of strongly-correlated fermions is studied in a degenerate, strongly- interacting atomic Fermi gas, first realized by our group with DOE support in 2002. This system, which exhibits strong spin pairing, is now widely studied and provides an important paradigm for testing predictions based on state-of-the-art many-body theory in fields ranging from nuclear matter to high temperature superfluidity and superconductivity. As the system is strongly interacting, both the superfluid and the normal fluid are nontrivial and of great interest. A central part of our program on Fermi gases is the connection between the study of thermodynamics, supported by DOE and the study of hydrodynamic transport, supported by NSF. This connection is especially interesting in view of a recent conjecture from the string theory community on the concept of nearly perfect normal fluids, which exhibit a minimum ratio of shear viscosity to entropy density in strongly-interacting, scale-invariant systems.

  14. Radio monitoring campaigns of six strongly lensed quasars

    NASA Astrophysics Data System (ADS)

    Rumbaugh, N.; Fassnacht, C. D.; McKean, J. P.; Koopmans, L. V. E.; Auger, M. W.; Suyu, S. H.

    2015-06-01

    We observed six strongly lensed, radio-loud quasars (MG 0414+0534, CLASS B0712+472, JVAS B1030+074, CLASS B1127+385, CLASS B1152+199, and JVAS B1938+666) in order to identify systems suitable for measuring cosmological parameters using time delays between their multiple images. These systems are in standard two- and four-image configurations, with B1938 having a faint secondary pair of images. Two separate monitoring campaigns were carried out using the Very Large Array (VLA) and upgraded VLA. Light curves were extracted for each individual lensed image and analysed for signs of intrinsic variability. While it was not possible to measure time delays from these data, χ2-based and structure function tests found evidence for variability in a majority of the light curves. B0712 and B1030 had particularly strong variations, exhibiting linear flux trends. These results suggest that most of these systems should be targeted with follow-up monitoring campaigns, especially B0712 and B1030. We estimate that we can measure time delays for these systems with precisions of 0.5-3.5 d using two more seasons of monitoring.

  15. Non-autonomous lattice systems with switching effects and delayed recovery

    NASA Astrophysics Data System (ADS)

    Han, Xiaoying; Kloeden, Peter E.

    2016-09-01

    The long term behavior of a type of non-autonomous lattice dynamical systems is investigated, where these have a diffusive nearest neighborhood interaction and discontinuous reaction terms with recoverable delays. This problem is of both biological and mathematical interests, due to its application in systems of excitable cells as well as general biological systems involving delayed recovery. The problem is formulated as an evolution inclusion with delays and the existence of weak and strong solutions is established. It is then shown that the solutions generate a set-valued non-autonomous dynamical system and that this non-autonomous dynamical system possesses a non-autonomous global pullback attractor.

  16. A fluid-structure interaction model with interior damping and delay in the structure

    NASA Astrophysics Data System (ADS)

    Peralta, Gilbert

    2016-03-01

    A coupled system of partial differential equations modeling the interaction of a fluid and a structure with delay in the feedback is studied. The model describes the dynamics of an elastic body immersed in a fluid that is contained in a vessel, whose boundary is made of a solid wall. The fluid component is modeled by the linearized Navier-Stokes equation, while the solid component is given by the wave equation neglecting transverse elastic force. Spectral properties and exponential or strong stability of the interaction model under appropriate conditions on the damping factor, delay factor and the delay parameter are established using a generalized Lax-Milgram method.

  17. Delayed Visual Feedback of One’s Own Action Promotes Sense of Control for Auditory Events

    PubMed Central

    Kawabe, Takahiro

    2015-01-01

    Sense of control refers to one’s feelings to control environmental events through one’s own action. A prevailing view is that the sense of control is strong (or is not diminished) when predicted sensory signals, which are generated in motor control mechanisms, are consistent with afferent sensory signals. Such intact sense of control often leads to the misjudgment of temporal relation between timings of one’s action and its effect (so-called, intentional binding). The present study showed that the intentional binding could be enhanced by the delayed visual feedback of an agent’s action. We asked participants to press a button to produce a tone as action outcome. In some conditions, they were given the delayed visual feedback of their button press. Participants judged whether the onset of the auditory outcome was delayed from the timing of their button press. Consequently, delay detection thresholds were significantly higher when the feedback was given 0.2 and 0.4 s delays than when no feedback was displayed to the participants. The results indicate that action agents misjudge the timing of their action (button press) in the presence of the delayed visual feedback of their action. Interestingly, delay detection thresholds were strongly correlated with the subjective magnitude of the sense of control. Thus, the sense of control is possibly determined by cross-modal processing for action-related and outcome-related sensory signals. PMID:26635552

  18. Conversion of linear time-invariant time-delay feedback systems into delay-differential equations with commensurate delays

    NASA Astrophysics Data System (ADS)

    Yamazaki, Tatsuya; Hagiwara, Tomomichi

    2014-08-01

    A new stability analysis method of time-delay systems (TDSs) called the monodromy operator approach has been studied under the assumption that a TDS is represented as a time-delay feedback system consisting of a finite-dimensional linear time-invariant (LTI) system and a pure delay. For applying this approach to TDSs described by delay-differential equations (DDEs), the problem of converting DDEs into representation as time-delay feedback systems has been studied. With regard to such a problem, it was shown that, under discontinuous initial functions, it is natural to define the solutions of DDEs in two different ways, and the above conversion problem was solved for each of these two definitions. More precisely, the solution of a DDE was represented as either the state of the finite-dimensional part of a time-delay feedback system or a part of the output of another time-delay feedback system, depending on which definition of the DDE solution one is talking about. Motivated by the importance in establishing a thorough relationship between time-delay feedback systems and DDEs, this paper discusses the opposite problem of converting time-delay feedback systems into representation as DDEs, including the discussions about the conversion of the initial conditions. We show that the state of (the finite-dimensional part of) a time-delay feedback system can be represented as the solution of a DDE in the sense of one of the two definitions, while its 'essential' output can be represented as that of another DDE in the sense of the other type of definition. Rigorously speaking, however, it is also shown that the latter representation is possible regardless of the initial conditions, while some initial condition could prevent the conversion into the former representation. This study hence establishes that the representation of TDSs as time-delay feedback systems possesses higher ability than that with DDEs, as description methods for LTI TDSs with commensurate delays.

  19. Delayed signatures of underground nuclear explosions

    NASA Astrophysics Data System (ADS)

    Carrigan, Charles R.; Sun, Yunwei; Hunter, Steven L.; Ruddle, David G.; Wagoner, Jeffrey L.; Myers, Katherine B. L.; Emer, Dudley F.; Drellack, Sigmund L.; Chipman, Veraun D.

    2016-03-01

    Radionuclide signals from underground nuclear explosions (UNEs) are strongly influenced by the surrounding hydrogeologic regime. One effect of containment is delay of detonation-produced radioxenon reaching the surface as well as lengthening of its period of detectability compared to uncontained explosions. Using a field-scale tracer experiment, we evaluate important transport properties of a former UNE site. We observe the character of signals at the surface due to the migration of gases from the post-detonation chimney under realistic transport conditions. Background radon signals are found to be highly responsive to cavity pressurization suggesting that large local radon anomalies may be an indicator of a clandestine UNE. Computer simulations, using transport properties obtained from the experiment, track radioxenon isotopes in the chimney and their migration to the surface. They show that the chimney surrounded by a fractured containment regime behaves as a leaky chemical reactor regarding its effect on isotopic evolution introducing a dependence on nuclear yield not previously considered. This evolutionary model for radioxenon isotopes is validated by atmospheric observations of radioxenon from a 2013 UNE in the Democratic People’s Republic of Korea (DPRK). Our model produces results similar to isotopic observations with nuclear yields being comparable to seismic estimates.

  20. Delayed signatures of underground nuclear explosions.

    PubMed

    Carrigan, Charles R; Sun, Yunwei; Hunter, Steven L; Ruddle, David G; Wagoner, Jeffrey L; Myers, Katherine B L; Emer, Dudley F; Drellack, Sigmund L; Chipman, Veraun D

    2016-01-01

    Radionuclide signals from underground nuclear explosions (UNEs) are strongly influenced by the surrounding hydrogeologic regime. One effect of containment is delay of detonation-produced radioxenon reaching the surface as well as lengthening of its period of detectability compared to uncontained explosions. Using a field-scale tracer experiment, we evaluate important transport properties of a former UNE site. We observe the character of signals at the surface due to the migration of gases from the post-detonation chimney under realistic transport conditions. Background radon signals are found to be highly responsive to cavity pressurization suggesting that large local radon anomalies may be an indicator of a clandestine UNE. Computer simulations, using transport properties obtained from the experiment, track radioxenon isotopes in the chimney and their migration to the surface. They show that the chimney surrounded by a fractured containment regime behaves as a leaky chemical reactor regarding its effect on isotopic evolution introducing a dependence on nuclear yield not previously considered. This evolutionary model for radioxenon isotopes is validated by atmospheric observations of radioxenon from a 2013 UNE in the Democratic People's Republic of Korea (DPRK). Our model produces results similar to isotopic observations with nuclear yields being comparable to seismic estimates. PMID:26979288

  1. Delayed signatures of underground nuclear explosions

    PubMed Central

    Carrigan, Charles R.; Sun, Yunwei; Hunter, Steven L.; Ruddle, David G.; Wagoner, Jeffrey L.; Myers, Katherine B. L.; Emer, Dudley F.; Drellack, Sigmund L.; Chipman, Veraun D.

    2016-01-01

    Radionuclide signals from underground nuclear explosions (UNEs) are strongly influenced by the surrounding hydrogeologic regime. One effect of containment is delay of detonation-produced radioxenon reaching the surface as well as lengthening of its period of detectability compared to uncontained explosions. Using a field-scale tracer experiment, we evaluate important transport properties of a former UNE site. We observe the character of signals at the surface due to the migration of gases from the post-detonation chimney under realistic transport conditions. Background radon signals are found to be highly responsive to cavity pressurization suggesting that large local radon anomalies may be an indicator of a clandestine UNE. Computer simulations, using transport properties obtained from the experiment, track radioxenon isotopes in the chimney and their migration to the surface. They show that the chimney surrounded by a fractured containment regime behaves as a leaky chemical reactor regarding its effect on isotopic evolution introducing a dependence on nuclear yield not previously considered. This evolutionary model for radioxenon isotopes is validated by atmospheric observations of radioxenon from a 2013 UNE in the Democratic People’s Republic of Korea (DPRK). Our model produces results similar to isotopic observations with nuclear yields being comparable to seismic estimates. PMID:26979288

  2. Delayed signatures of underground nuclear explosions

    DOE PAGESBeta

    Carrigan, Charles R.; Sun, Yunwei; Hunter, Steven L.; Ruddle, David G.; Wagoner, Jeffrey L.; Myers, Katherine B. L.; Emer, Dudley F.; Drellack, Sigmund L.; Chipman, Veraun D.

    2016-03-16

    Radionuclide signals from underground nuclear explosions (UNEs) are strongly influenced by the surrounding hydrogeologic regime. One effect of containment is delay of detonation-produced radioxenon reaching the surface as well as lengthening of its period of detectability compared to uncontained explosions. Using a field-scale tracer experiment, we evaluate important transport properties of a former UNE site. Here, we observe the character of signals at the surface due to the migration of gases from the post-detonation chimney under realistic transport conditions. Background radon signals are found to be highly responsive to cavity pressurization suggesting that large local radon anomalies may be anmore » indicator of a clandestine UNE. Computer simulations, using transport properties obtained from the experiment, track radioxenon isotopes in the chimney and their migration to the surface. They show that the chimney surrounded by a fractured containment regime behaves as a leaky chemical reactor regarding its effect on isotopic evolution introducing a dependence on nuclear yield not previously considered. This evolutionary model for radioxenon isotopes is validated by atmospheric observations of radioxenon from a 2013 UNE in the Democratic People’s Republic of Korea (DPRK). In conclusion, our model produces results similar to isotopic observations with nuclear yields being comparable to seismic estimates.« less

  3. Strongly Secure Linear Network Coding

    NASA Astrophysics Data System (ADS)

    Harada, Kunihiko; Yamamoto, Hirosuke

    In a network with capacity h for multicast, information Xh=(X1, X2, …, Xh) can be transmitted from a source node to sink nodes without error by a linear network code. Furthermore, secret information Sr=(S1, S2, …, Sr) can be transmitted securely against wiretappers by k-secure network coding for k≤h-r. In this case, no information of the secret leaks out even if an adversary wiretaps k edges, i. e. channels. However, if an adversary wiretaps k+1 edges, some Si may leak out explicitly. In this paper, we propose strongly k-secure network coding based on strongly secure ramp secret sharing schemes. In this coding, no information leaks out for every (Si1, Si2, …,Sir-j) even if an adversary wiretaps k+j channels. We also give an algorithm to construct a strongly k-secure network code directly and a transform to convert a nonsecure network code to a strongly k-secure network code. Furthermore, some sufficient conditions of alphabet size to realize the strongly k-secure network coding are derived for the case of k

  4. Diagnostic delay in oral squamous cell carcinoma: the role of cognitive and psychological variables

    PubMed Central

    Panzarella, Vera; Pizzo, Giuseppe; Calvino, Francesco; Compilato, Domenico; Colella, Giuseppe; Campisi, Giuseppina

    2014-01-01

    This retrospective study investigated, in two cohorts of subjects living in Southern Italy and awaiting treatment for oral squamous cell carcinoma (OSCC), the variables related to diagnostic delay ascribable to the patient, with particular reference to the cognitive and psychological ones. A total of 156 patients with OSCC (mean age: 62 years, M/F: 2.39∶1) were recruited at the Universities of Palermo and Naples. Risk factors related to patient delay included: sociodemographic, health-related, cognitive and psychological variables. The analysis was conducted by considering two different delay ranges: dichotomous (≤1 month vs. >1 month) and polytomous (<1 month, 1–3 months, >3 months) delay. Data were investigated by univariate and multivariate analyses and a P value ≤0.05 was considered statistically significant. For both delay measurements, the most relevant variables were: ‘Personal experience of cancer' (dichotomous delay: P=0.05, odds ratio (OR)=0.33, 95% confidence interval (CI)=0.11–0.99; polytomous delay: P=0.006, Chi-square=10.224) and ‘Unawareness' (dichotomous delay: P<0.01, OR=4.96, 95% CI=2.16–11.37; polytomous delay: P=0.087, Chi-square=4.77). Also ‘Denial' (P<0.01, OR=6.84, 95% CI=2.31–20.24) and ‘Knowledge of cancer' (P=0.079, Chi-square=8.359) were found to be statistically significant both for dichotomous and for polytomous categorization of delay, respectively. The findings of this study indicated that, in the investigated cohorts, the knowledge about cancer issues is strongly linked to the patient delay. Educational interventions on the Mediterranean population are necessary in order to increase the patient awareness and to emphasize his/her key role in early diagnosis of OSCC. PMID:24287962

  5. Diagnostic delay in oral squamous cell carcinoma: the role of cognitive and psychological variables.

    PubMed

    Panzarella, Vera; Pizzo, Giuseppe; Calvino, Francesco; Compilato, Domenico; Colella, Giuseppe; Campisi, Giuseppina

    2014-03-01

    This retrospective study investigated, in two cohorts of subjects living in Southern Italy and awaiting treatment for oral squamous cell carcinoma (OSCC), the variables related to diagnostic delay ascribable to the patient, with particular reference to the cognitive and psychological ones. A total of 156 patients with OSCC (mean age: 62 years, M/F: 2.39∶1) were recruited at the Universities of Palermo and Naples. Risk factors related to patient delay included: sociodemographic, health-related, cognitive and psychological variables. The analysis was conducted by considering two different delay ranges: dichotomous (≤1 month vs. >1 month) and polytomous (<1 month, 1-3 months, >3 months) delay. Data were investigated by univariate and multivariate analyses and a P value ≤0.05 was considered statistically significant. For both delay measurements, the most relevant variables were: 'Personal experience of cancer' (dichotomous delay: P=0.05, odds ratio (OR)=0.33, 95% confidence interval (CI)=0.11-0.99; polytomous delay: P=0.006, Chi-square=10.224) and 'Unawareness' (dichotomous delay: P<0.01, OR=4.96, 95% CI=2.16-11.37; polytomous delay: P=0.087, Chi-square=4.77). Also 'Denial' (P<0.01, OR=6.84, 95% CI=2.31-20.24) and 'Knowledge of cancer' (P=0.079, Chi-square=8.359) were found to be statistically significant both for dichotomous and for polytomous categorization of delay, respectively. The findings of this study indicated that, in the investigated cohorts, the knowledge about cancer issues is strongly linked to the patient delay. Educational interventions on the Mediterranean population are necessary in order to increase the patient awareness and to emphasize his/her key role in early diagnosis of OSCC. PMID:24287962

  6. Extreme fluctuations in stochastic network coordination with time delays

    NASA Astrophysics Data System (ADS)

    Hunt, D.; Molnár, F.; Szymanski, B. K.; Korniss, G.

    2015-12-01

    We study the effects of uniform time delays on the extreme fluctuations in stochastic synchronization and coordination problems with linear couplings in complex networks. We obtain the average size of the fluctuations at the nodes from the behavior of the underlying modes of the network. We then obtain the scaling behavior of the extreme fluctuations with system size, as well as the distribution of the extremes on complex networks, and compare them to those on regular one-dimensional lattices. For large complex networks, when the delay is not too close to the critical one, fluctuations at the nodes effectively decouple, and the limit distributions converge to the Fisher-Tippett-Gumbel density. In contrast, fluctuations in low-dimensional spatial graphs are strongly correlated, and the limit distribution of the extremes is the Airy density. Finally, we also explore the effects of nonlinear couplings on the stability and on the extremes of the synchronization landscapes.

  7. Cell probing by delayed luminescence

    NASA Astrophysics Data System (ADS)

    Musumeci, Francesco; Ballerini, Monica; Baroni, Giuliana; Costato, Michele; Ferraro, Lorenzo; Milani, Marziale; Scordino, Agata; Triglia, Antonio

    1999-05-01

    Delayed luminescence (D.L.) is a measure that provides important information on biological systems fields, structures and activities, by counting impinging and emitted photons. Many recent experimental works have shown the existence of a close connection, sometimes analytically expressed between the biological state of the system and D.L. parameters. Our investigations aim to show that D.L. is a workable analytical technique covering a large number of disciplinary fields, from agriculture to pollution control and from medical diagnostics to food quality control. The authors have conducted systematic research about D.L. from unicellular alga Acetabularia acetabulum to Saccharomyces cerevisiae yeast cultures and about more complex systems such as Soya seed (Glycine max, L.) and its dependence on sample preparation, history, intracellular signaling, metabolism and pollutant presence. We will discuss the most relevant results together with theoretical considerations on the basic interaction at work between biological systems and electromagnetic fields.

  8. Does it pay to delay? Flesh flies show adaptive plasticity in reproductive timing.

    PubMed

    Wessels, Frank J; Kristal, Ross; Netter, Fleta; Hatle, John D; Hahn, Daniel A

    2011-02-01

    Life-history plasticity is widespread among organisms. However, an important question is whether it is adaptive. Most models for plasticity in life-history timing predict that animals, once they have reached the minimal nutritional threshold under poor conditions, will accelerate development or time to reproduction. Adaptive delays in reproduction are not common, especially in short-lived species. Examples of adaptive reproductive delays exist in mammalian populations experiencing strong interspecific (e.g., predation) and intraspecific (e.g., infanticide) competition. But are there other environmental factors that may trigger an adaptive delay in reproductive timing? We show that the short-lived flesh fly Sarcophaga crassipalpis will delay reproduction under nutrient-poor conditions, even though it has already met the minimal nutritional threshold for reproduction. We test whether this delay strategy is an adaptive response allowing the scavenger time to locate more resources by experimentally providing supplemental protein pulses (early, mid and late) throughout the reproductive delay period. Flies receiving additional protein produced more and larger eggs, demonstrating a benefit of the delay. In addition, by tracking the allocation of carbon from the pulses using stable isotopes, we show that flies receiving earlier pulses incorporated more carbon into eggs and somatic tissue than those given a later pulse. These results indicate that the reproductive delay in S. crassipalpis is consistent with adaptive post-threshold plasticity, a nutritionally linked reproductive strategy that has not been reported previously in an invertebrate species. PMID:20953961

  9. Improved outcomes for emergency department patients whose ambulance off-stretcher time is not delayed

    PubMed Central

    Crilly, Julia; Keijzers, Gerben; Tippett, Vivienne; O’Dwyer, John; Lind, James; Bost, Nerolie; O’Dwyer, Marilla; Shiels, Sue; Wallis, Marianne

    2015-01-01

    Objective To describe and compare characteristics and outcomes of patients who arrive by ambulance to the ED. We aimed to (i) compare patients with a delayed ambulance offload time (AOT) >30 min with those who were not delayed; and (ii) identify predictors of an ED length of stay (LOS) of >4 h for ambulance-arriving patients. Methods A retrospective, multi-site cohort study was undertaken in Australia using 12 months of linked health data (September 2007–2008). Outcomes of AOT delayed and non-delayed presentations were compared. Logistic regression analysis was undertaken to identify predictors of an ED LOS of >4 h. Results Of the 40 783 linked, analysable ambulance presentations, AOT delay of >30 min was experienced by 15%, and 63% had an ED LOS of >4 h. Patients with an AOT <30 min had better outcomes for: time to triage; ambulance time at hospital; time to see healthcare professional; proportion seen within recommended triage time frame; and ED LOS for both admitted and non-admitted patients. In-hospital mortality did not differ. Strong predictors of an ED LOS >4 h included: hospital admission, older age, triage category, and offload delay >30 min. Conclusion Patients arriving to the ED via ambulance and offloaded within 30 min experience better outcomes than those delayed. Given that offload delay is a modifiable predictor of an ED LOS of >4 h, targeted improvements in the ED arrival process for ambulance patients might be useful. PMID:25940975

  10. Strong localization of photonics in symmetric Fibonacci superlattices

    NASA Astrophysics Data System (ADS)

    Cheng, Y. H.; Tsao, C. W.; Chen, C. H.; Hsueh, W. J.

    2015-07-01

    Strong localization from the Fabry-Pérot-like resonances that occur in symmetric Fibonacci superlattices is presented in this study. When compared with traditional Fabry-Pérot resonators, in symmetric Fibonacci superlattices, the middle space is a variant rather than an invariant half-wavelength thickness for each resonance with different orders. In addition, the electric fields of the resonances may be located on both sides of the space layer in the superlattice, which is in contrast to those in a traditional Fabry-Pérot resonator. The electric field of the resonances is strongly localized as the generation order increases. Moreover, the group delays of these peaks increase with generation order. More strongly localized modes can be found from the symmetric Fibonacci superlattices than from the traditional Fabry-Pérot resonators, which makes the proposed structure an attractive alternative to a wide variety of optoelectronic devices.

  11. Nonlinear Strong Ground Motion in the 2004 Parkfield Earthquake

    NASA Astrophysics Data System (ADS)

    Rubinstein, J. L.; Beroza, G. C.

    2004-12-01

    Previous studies [Rubinstein and Beroza, 2004 (a,b); Schaff and Beroza, 2004] have shown that the strong shaking resultant from medium and large earthquakes can result in the formation and/or growth of microcracks in the near surface, resulting in reduced seismic velocities at distances exceeding 30km. We use moving window cross correlation on the waveforms of repeating earthquake sequences in the Parkfield area to identify temporal changes in wave propagation coincident with the earthquake, evidence of the damage that the Parkfield earthquake caused. The largest delays we observe are in the S coda, and exceed 10ms. Parkfield provides a unique opportunity where we can better understand to what depth damage caused by strong ground motion (nonlinear strong ground motion) occurs as there are many downhole and uphole seismometers in the region.

  12. Stochastic switching in delay-coupled oscillators.

    PubMed

    D'Huys, Otti; Jüngling, Thomas; Kinzel, Wolfgang

    2014-09-01

    A delay is known to induce multistability in periodic systems. Under influence of noise, coupled oscillators can switch between coexistent orbits with different frequencies and different oscillation patterns. For coupled phase oscillators we reduce the delay system to a nondelayed Langevin equation, which allows us to analytically compute the distribution of frequencies and their corresponding residence times. The number of stable periodic orbits scales with the roundtrip delay time and coupling strength, but the noisy system visits only a fraction of the orbits, which scales with the square root of the delay time and is independent of the coupling strength. In contrast, the residence time in the different orbits is mainly determined by the coupling strength and the number of oscillators, and only weakly dependent on the coupling delay. Finally we investigate the effect of a detuning between the oscillators. We demonstrate the generality of our results with delay-coupled FitzHugh-Nagumo oscillators. PMID:25314515

  13. Delay banking for air traffic management

    NASA Technical Reports Server (NTRS)

    Green, Steven M. (Inventor)

    2007-01-01

    A method and associated system for time delay banking for aircraft arrival time, aircraft departure time and/or en route flight position. The delay credit value for a given flight may decrease with passage of time and may be transferred to or traded with other flights having the same or a different user (airline owner or operator). The delay credit value for a given aircraft flight depends upon an initial delay credit value, which is determined by a central system and depends upon one or more other flight characteristics. Optionally, the delay credit value decreases with passage of time. Optionally, a transaction cost is assessed against a delay credit value that is used on behalf of another flight with the same user or is traded with a different user.

  14. CGI delay compensation. [Computer Generated Image

    NASA Technical Reports Server (NTRS)

    Mcfarland, R. E.

    1986-01-01

    Computer-generated graphics in real-time helicopter simulation produces objectionable scene-presentation time delays. In the flight simulation laboratory at Ames Research Center, it has been determined that these delays have an adverse influence on pilot performance during agressive tasks such as nap of the earth (NOE) maneuvers. Using contemporary equipment, computer generated image (CGI) time delays are an unavoidable consequence of the operations required for scene generation. However, providing that magnitude distortions at higher frequencies are tolerable, delay compensation is possible over a restricted frequency range. This range, assumed to have an upper limit of perhaps 10 or 15 rad/sec, conforms approximately to the bandwidth associated with helicopter handling qualities research. A compensation algorithm is introduced here and evaluated in terms of tradeoffs in frequency responses. The algorithm has a discrete basis and accommodates both a large, constant transport delay interval and a periodic delay interval, as associated with asynchronous operations.

  15. Strongly interacting ultracold polar molecules

    NASA Astrophysics Data System (ADS)

    Gadway, Bryce; Yan, Bo

    2016-08-01

    This paper reviews recent advances in the study of strongly interacting systems of dipolar molecules. Heteronuclear molecules feature large and tunable electric dipole moments, which give rise to long-range and anisotropic dipole–dipole interactions. Ultracold samples of dipolar molecules with long-range interactions offer a unique platform for quantum simulations and the study of correlated many-body physics. We provide an introduction to the physics of dipolar quantum gases, both electric and magnetic, and summarize the multipronged efforts to bring dipolar molecules into the quantum regime. We discuss in detail the recent experimental progress in realizing and studying strongly interacting systems of polar molecules trapped in optical lattices, with particular emphasis on the study of interacting spin systems and non-equilibrium quantum magnetism. Finally, we conclude with a brief discussion of the future prospects for studies of strongly interacting dipolar molecules.

  16. The SNAP Strong Lens Survey

    SciTech Connect

    Marshall, P.

    2005-01-03

    Basic considerations of lens detection and identification indicate that a wide field survey of the types planned for weak lensing and Type Ia SNe with SNAP are close to optimal for the optical detection of strong lenses. Such a ''piggy-back'' survey might be expected even pessimistically to provide a catalogue of a few thousand new strong lenses, with the numbers dominated by systems of faint blue galaxies lensed by foreground ellipticals. After sketching out our strategy for detecting and measuring these galaxy lenses using the SNAP images, we discuss some of the scientific applications of such a large sample of gravitational lenses: in particular we comment on the partition of information between lens structure, the source population properties and cosmology. Understanding this partitioning is key to assessing strong lens cosmography's value as a cosmological probe.

  17. Strong Photoassociation in Ultracold Fermions

    NASA Astrophysics Data System (ADS)

    Jing, Li; Jamison, Alan; Rvachov, Timur; Ebadi, Sepher; Son, Hyungmok; Jiang, Yijun; Zwierlein, Martin; Ketterle, Wolfgang

    2016-05-01

    Despite many studies there are still open questions about strong photoassociation in ultracold gases. Photoassociation occurs only at short range and thus can be used as a tool to probe and control the two-body correlation function in an interacting many-body system and to engineer Hamiltonians using dissipation. We propose the possibility to slow down decoherence by photoassociation through the quantum Zeno effect. This can realized by shining strong photoassociation light on the superposition of the lowest two hyperfine states of Lithium 6. NSF, ARO-MURI, Samsung, NSERC.

  18. Compact programmable photonic variable delay devices

    NASA Technical Reports Server (NTRS)

    Yao, X. Steve (Inventor)

    1999-01-01

    Optical variable delay devices for providing variable true time delay to multiple optical beams simultaneously. A ladder-structured variable delay device comprises multiple basic building blocks stacked on top of each other resembling a ladder. Each basic building block has two polarization beamsplitters and a polarization rotator array arranged to form a trihedron; Controlling an array element of the polarization rotator array causes a beam passing through the array element either going up to a basic building block above it or reflect back towards a block below it. The beams going higher on the ladder experience longer optical path delay. An index-switched optical variable delay device comprises of many birefringent crystal segments connected with one another, with a polarization rotator array sandwiched between any two adjacent crystal segments. An array element in the polarization rotator array controls the polarization state of a beam passing through the element, causing the beam experience different refractive indices or path delays in the following crystal segment. By independently control each element in each polarization rotator array, variable optical path delays of each beam can be achieved. Finally, an index-switched variable delay device and a ladder-structured variable device are cascaded to form a new device which combines the advantages of the two individual devices. This programmable optic device has the properties of high packing density, low loss, easy fabrication, and virtually infinite bandwidth. The device is inherently two dimensional and has a packing density exceeding 25 lines/cm.sup.2. The delay resolution of the device is on the order of a femtosecond (one micron in space) and the total delay exceeds 10 nanosecond. In addition, the delay is reversible so that the same delay device can be used for both antenna transmitting and receiving.

  19. Delays in the human heartbeat dynamics

    NASA Astrophysics Data System (ADS)

    Alvarez-Ramirez, Jose; Rodriguez, Eduardo; Echeverría, Juan Carlos

    2009-06-01

    This paper explores the possibility of applying statistical nonlinear physics methods to elucidate the underlying mechanisms controlling the heart rate. In particular, the presence of delays in RR interval dynamics is studied by using a lagged detrended fluctuation analysis. The results indicate that patients with congestive heart failure (CHF) have a prolonged time delay in the baroreflex response. Some implications of large delays for the functioning of autonomic control in subjects with CHF are discussed.

  20. Time delay plots of unflavoured baryons

    NASA Astrophysics Data System (ADS)

    Kelkar, N. G.; Nowakowski, M.; Khemchandani, K. P.; Jain, S. R.

    2004-01-01

    We explore the usefulness of the existing relations between the S-matrix and time delay in characterizing baryon resonances in pion-nucleon scattering. We draw attention to the fact that the existence of a positive maximum in time delay is a necessary criterion for the existence of a resonance and should be used as a constraint in conventional analyses which locate resonances from poles of the S-matrix and Argand diagrams. The usefulness of the time delay plots of resonances is demonstrated through a detailed analysis of the time delay in several partial waves of πN elastic scattering.

  1. Computation of signal delays in RC networks

    NASA Technical Reports Server (NTRS)

    Hidalgo, Juan Carlos; Narendran, Paliath; Chaiken, Seth

    1993-01-01

    A model for signal delay computation in RC networks is presented. The strength of the paradigm is its generality and simplicity. The definition of delay is applicable to RC meshes with potential resistive attenuating paths to ground. The algorithms can also be applied to undriven circuits (static charge sharing) and circuits with initial charge. To compute the delays, each node in the network is explored locally to derive a system of sparse linear equations. The solutions of the system are delay values based on the Elmore time constant at each point in the circuit.

  2. Oscillation onset in neural delayed feedback

    SciTech Connect

    Longtin, A.

    1990-01-01

    This paper studies dynamical aspects of neural systems with delayed negative feedback modelled by nonlinear delay-differential equations. These systems undergo a Hopf bifurcation from a stable fixed point to a limit cycle oscillation as certain parameters are varied. We show that their frequency of oscillation is robust to parameter variations and noisy fluctuations, a property that makes these systems good candidates for pacemakers. The onset of oscillation is postponed by both additive and parametric noise in the sense that the state variable spends more time near the fixed point. Finally, we show that a distributed delay (rather than a fixed delay) also stabilizes the fixed point solution. 40 refs., 2 figs.

  3. Second order Kerr-Newman time delay

    NASA Astrophysics Data System (ADS)

    He, G.; Lin, W.

    2016-01-01

    The explicit form for the post-Newtonian gravitational time delay of light signals propagating on the equatorial plane of a Kerr-Newman black hole is derived. Based on the null geodesic in Kerr-Newman spacetime, we adopt the iterative method to calculate the time delay. Our result reduces to the previous formulation for the Kerr black hole if we drop the contribution from the electrical charge. Our time-delay formula for the Reissner-Nordström geometry is different from the previous publication [Phys. Rev. D 69, 023002 (2004)], in which the largest second order contribution to the time delay is missing.

  4. Computation of signal delays in RC networks

    NASA Astrophysics Data System (ADS)

    Hidalgo, Juan Carlos; Narendran, Paliath; Chaiken, Seth

    A model for signal delay computation in RC networks is presented. The strength of the paradigm is its generality and simplicity. The definition of delay is applicable to RC meshes with potential resistive attenuating paths to ground. The algorithms can also be applied to undriven circuits (static charge sharing) and circuits with initial charge. To compute the delays, each node in the network is explored locally to derive a system of sparse linear equations. The solutions of the system are delay values based on the Elmore time constant at each point in the circuit.

  5. Literacy Activities for Developmentally Delayed Adults.

    ERIC Educational Resources Information Center

    Giordano, Gerard; D'Alonzo, Bruno J.

    1993-01-01

    Reviews six models of prereading programs for developmentally delayed adults: readinglike behavior, picture reading, global features of books, print in the environment, labeling, and rebus symbols. (SK)

  6. Intron Delays and Transcriptional Timing during Development

    PubMed Central

    Swinburne, Ian A.; Silver, Pamela A.

    2010-01-01

    The time taken to transcribe most metazoan genes is significant because of the substantial length of introns. Developmentally regulated gene networks, where timing and dynamic patterns of expression are critical, may be particularly sensitive to intron delays. We revisit and comment on a perspective last presented by Thummel 16 years ago: transcriptional delays may contribute to timing mechanisms during development. We discuss the presence of intron delays in genetic networks. We consider how delays can impact particular moments during development, which mechanistic attributes of transcription can influence them, how they can be modeled, and how they can be studied using recent technological advances as well as classical genetics. PMID:18331713

  7. PREFACE: Strongly Coupled Coulomb Systems Strongly Coupled Coulomb Systems

    NASA Astrophysics Data System (ADS)

    Neilson, David; Senatore, Gaetano

    2009-05-01

    This special issue contains papers presented at the International Conference on Strongly Coupled Coulomb Systems (SCCS), held from 29 July-2 August 2008 at the University of Camerino. Camerino is an ancient hill-top town located in the Apennine mountains of Italy, 200 kilometres northeast of Rome, with a university dating back to 1336. The Camerino conference was the 11th in a series which started in 1977: 1977: Orleans-la-Source, France, as a NATO Advanced Study Institute on Strongly Coupled Plasmas (hosted by Marc Feix and Gabor J Kalman) 1982: Les Houches, France (hosted by Marc Baus and Jean-Pierre Hansen) 1986: Santa Cruz, California, USA (hosted by Forrest J Rogers and Hugh E DeWitt) 1989: Tokyo, Japan (hosted by Setsuo Ichimaru) 1992: Rochester, New York, USA (hosted by Hugh M Van Horn and Setsuo Ichimaru) 1995: Binz, Germany (hosted by Wolf Dietrich Kraeft and Manfred Schlanges) 1997: Boston, Massachusetts, USA (hosted by Gabor J Kalman) 1999: St Malo, France (hosted by Claude Deutsch and Bernard Jancovici) 2002: Santa Fe, New Mexico, USA (hosted by John F Benage and Michael S Murillo) 2005: Moscow, Russia (hosted by Vladimir E Fortov and Vladimir Vorob'ev). The name of the series was changed in 1996 from Strongly Coupled Plasmas to Strongly Coupled Coulomb Systems to reflect a wider range of topics. 'Strongly Coupled Coulomb Systems' encompasses diverse many-body systems and physical conditions. The purpose of the conferences is to provide a regular international forum for the presentation and discussion of research achievements and ideas relating to a variety of plasma, liquid and condensed matter systems that are dominated by strong Coulomb interactions between their constituents. Each meeting has seen an evolution of topics and emphases that have followed new discoveries and new techniques. The field has continued to see new experimental tools and access to new strongly coupled conditions, most recently in the areas of warm matter, dusty plasmas

  8. Strong coupling electroweak symmetry breaking

    SciTech Connect

    Barklow, T.L.; Burdman, G.; Chivukula, R.S.

    1997-04-01

    The authors review models of electroweak symmetry breaking due to new strong interactions at the TeV energy scale and discuss the prospects for their experimental tests. They emphasize the direct observation of the new interactions through high-energy scattering of vector bosons. They also discuss indirect probes of the new interactions and exotic particles predicted by specific theoretical models.

  9. A strongly coupled anyon material

    NASA Astrophysics Data System (ADS)

    Brattan, Daniel K.

    2015-11-01

    We use alternative quantisation of the D3-D5 system to explore properties of a strongly coupled anyon material at finite density and temperature. We study the transport properties of the material and find both diffusion and massive holographic zero sound modes. By studying the anyon number conductivity we also find evidence for the anyonic analogue of the metal-insulator transition.

  10. STRONG HEART STUDY DATA BOOK

    EPA Science Inventory

    Epidemiologic study of cardiovascular disease in American Indians. Examination on the prevalence of major risk factors of CVD in American Indian men and women ages 45-74 in the American Indian communities from the three centers that participate in the Strong Heart Study.

  11. Improved delay-dependent stability criteria for neutral-type systems with time-varying delays: a delayed decomposition approach

    NASA Astrophysics Data System (ADS)

    Liu, Pin-Lin

    2014-08-01

    This paper discusses the neutral system with time-varying delay. Firstly, by developing a delayed decomposition approach and introducing integral inequality approach, the information of the delayed plant states can be taken into full consideration, and new delay-dependent sufficient stability criteria are obtained in terms of linear matrix inequalities (LMIs). Then, based on the Lyapunov method, delay-dependent stability criteria are devised by taking the relationship between the terms in the Leibniz-Newton formula into account. The criteria are derived in terms of LMIs, which can be easily solved by using various convex optimization algorithms. Three illustrative numerical examples are given to show the less conservatism of our obtained results and the effectiveness of the proposed method.

  12. Quality control by <strong>HyperS>pectral <strong>I>maging (HSI) in solid waste recycling: logics, algorithms and procedures

    NASA Astrophysics Data System (ADS)

    Bonifazi, Giuseppe; Serranti, Silvia

    2014-03-01

    In secondary raw materials and recycling sectors, the products quality represents, more and more, the key issue to pursuit in order to be competitive in a more and more demanding market, where quality standards and products certification play a preheminent role. These goals assume particular importance when recycling actions are applied. Recovered products, resulting from waste materials, and/or dismissed products processing, are, in fact, always seen with a certain suspect. An adequate response of the industry to the market can only be given through the utilization of equipment and procedures ensuring pure, high-quality production, and efficient work and cost. All these goals can be reached adopting not only more efficient equipment and layouts, but also introducing new processing logics able to realize a full control of the handled material flow streams fulfilling, at the same time, i) an easy management of the procedures, ii) an efficient use of the energy, iii) the definition and set up of reliable and robust procedures, iv) the possibility to implement network connectivity capabilities finalized to a remote monitoring and control of the processes and v) a full data storage, analysis and retrieving. Furthermore the ongoing legislation and regulation require the implementation of recycling infrastructure characterised by high resources efficiency and low environmental impacts, both aspects being strongly linked to the waste materials and/or dismissed products original characteristics. For these reasons an optimal recycling infrastructure design primarily requires a full knowledge of the characteristics of the input waste. What previously outlined requires the introduction of a new important concept to apply in solid waste recycling, the recycling-oriented characterization, that is the set of actions addressed to strategically determine selected attributes, in order to get goaloriented data on waste for the development, implementation or improvement of recycling

  13. Spike phase synchronization in delayed-coupled neural networks: Uniform vs. non-uniform transmission delay

    NASA Astrophysics Data System (ADS)

    Jalili, Mahdi

    2013-03-01

    In this paper, we investigated phase synchronization in delayed dynamical networks. Non-identical spiking Hindmarsh-Rose neurons were considered as individual dynamical systems and coupled through a number of network structures such as scale-free, Erdős-Rényi, and modular. The individual neurons were coupled through excitatory chemical synapses with uniform or distributed time delays. The profile of spike phase synchrony was different when the delay was uniform across the edges as compared to the case when it was distributed, i.e., different delays for the edges. When an identical transmission delay was considered, a quasi-periodic pattern was observed in the spike phase synchrony. There were specific values of delay where the phase synchronization reached to its peaks. The behavior of the phase synchronization in the networks with non-uniform delays was different with the former case, where the phase synchrony decreased as distributed delays introduced to the networks.

  14. PREFACE: Strongly correlated electron systems Strongly correlated electron systems

    NASA Astrophysics Data System (ADS)

    Saxena, Siddharth S.; Littlewood, P. B.

    2012-07-01

    This special section is dedicated to the Strongly Correlated Electron Systems Conference (SCES) 2011, which was held from 29 August-3 September 2011, in Cambridge, UK. SCES'2011 is dedicated to 100 years of superconductivity and covers a range of topics in the area of strongly correlated systems. The correlated electronic and magnetic materials featured include f-electron based heavy fermion intermetallics and d-electron based transition metal compounds. The selected papers derived from invited presentations seek to deepen our understanding of the rich physical phenomena that arise from correlation effects. The focus is on quantum phase transitions, non-Fermi liquid phenomena, quantum magnetism, unconventional superconductivity and metal-insulator transitions. Both experimental and theoretical work is presented. Based on fundamental advances in the understanding of electronic materials, much of 20th century materials physics was driven by miniaturisation and integration in the electronics industry to the current generation of nanometre scale devices. The achievements of this industry have brought unprecedented advances to society and well-being, and no doubt there is much further to go—note that this progress is founded on investments and studies in the fundamentals of condensed matter physics from more than 50 years ago. Nevertheless, the defining challenges for the 21st century will lie in the discovery in science, and deployment through engineering, of technologies that can deliver the scale needed to have an impact on the sustainability agenda. Thus the big developments in nanotechnology may lie not in the pursuit of yet smaller transistors, but in the design of new structures that can revolutionise the performance of solar cells, batteries, fuel cells, light-weight structural materials, refrigeration, water purification, etc. The science presented in the papers of this special section also highlights the underlying interest in energy-dense materials, which

  15. EDITORIAL: Strongly correlated electron systems Strongly correlated electron systems

    NASA Astrophysics Data System (ADS)

    Ronning, Filip; Batista, Cristian

    2011-03-01

    Strongly correlated electrons is an exciting and diverse field in condensed matter physics. This special issue aims to capture some of that excitement and recent developments in the field. Given that this issue was inspired by the 2010 International Conference on Strongly Correlated Electron Systems (SCES 2010), we briefly give some history in order to place this issue in context. The 2010 International Conference on Strongly Correlated Electron Systems was held in Santa Fe, New Mexico, a reunion of sorts from the 1989 International Conference on the Physics of Highly Correlated Electron Systems that also convened in Santa Fe. SCES 2010—co-chaired by John Sarrao and Joe Thompson—followed the tradition of earlier conferences, in this century, hosted by Buzios (2008), Houston (2007), Vienna (2005), Karlsruhe (2004), Krakow (2002) and Ann Arbor (2001). Every three years since 1997, SCES has joined the International Conference on Magnetism (ICM), held in Recife (2000), Rome (2003), Kyoto (2006) and Karlsruhe (2009). Like its predecessors, SCES 2010 topics included strongly correlated f- and d-electron systems, heavy-fermion behaviors, quantum-phase transitions, non-Fermi liquid phenomena, unconventional superconductivity, and emergent states that arise from electronic correlations. Recent developments from studies of quantum magnetism and cold atoms complemented the traditional subjects and were included in SCES 2010. 2010 celebrated the 400th anniversary of Santa Fe as well as the birth of astronomy. So what's the connection to SCES? The Dutch invention of the first practical telescope and its use by Galileo in 1610 and subsequent years overturned dogma that the sun revolved about the earth. This revolutionary, and at the time heretical, conclusion required innovative combinations of new instrumentation, observation and mathematics. These same combinations are just as important 400 years later and are the foundation of scientific discoveries that were discussed

  16. New delay dependent stability criteria for recurrent neural networks with interval time-varying delay.

    PubMed

    Yang, Qiongfen; Ren, Quanhong; Xie, Xuemei

    2014-07-01

    This paper is concerned with the delay dependent stability criteria for a class of static recurrent neural networks with interval time-varying delay. By choosing an appropriate Lyapunov-Krasovskii functional and employing a delay partitioning method, the less conservative condition is obtained. Furthermore, the LMIs-based condition depend on the lower and upper bounds of time delay. Finally, a numerical example is also designated to verify the reduced conservatism of developed criteria. PMID:24908560

  17. Delay Banking for Managing Air Traffic

    NASA Technical Reports Server (NTRS)

    Green, Steve

    2008-01-01

    Delay banking has been invented to enhance air-traffic management in a way that would increase the degree of fairness in assigning arrival, departure, and en-route delays and trajectory deviations to aircraft impacted by congestion in the national airspace system. In delay banking, an aircraft operator (airline, military, general aviation, etc.) would be assigned a numerical credit when any of their flights are delayed because of an air-traffic flow restriction. The operator could subsequently bid against other operators competing for access to congested airspace to utilize part or all of its accumulated credit. Operators utilize credits to obtain higher priority for the same flight, or other flights operating at the same time, or later, in the same airspace, or elsewhere. Operators could also trade delay credits, according to market rules that would be determined by stakeholders in the national airspace system. Delay banking would be administered by an independent third party who would use delay banking automation to continually monitor flights, allocate delay credits, maintain accounts of delay credits for participating airlines, mediate bidding and the consumption of credits of winning bidders, analyze potential transfers of credits within and between operators, implement accepted transfers, and ensure fair treatment of all participating operators. A flow restriction can manifest itself in the form of a delay in assigned takeoff time, a reduction in assigned airspeed, a change in the position for the aircraft in a queue of all aircraft in a common stream of traffic (e.g., similar route), a change in the planned altitude profile for an aircraft, or change in the planned route for the aircraft. Flow restrictions are typically imposed to mitigate traffic congestion at an airport or in a region of airspace, particularly congestion due to inclement weather, or the unavailability of a runway or region of airspace. A delay credit would be allocated to an operator of a

  18. Telepresence, time delay, and adaptation

    NASA Technical Reports Server (NTRS)

    Held, Richard; Durlach, Nathaniel

    1989-01-01

    Displays are now being used extensively throughout the society. More and more time is spent watching television, movies, computer screens, etc. Furthermore, in an increasing number of cases, the observer interacts with the display and plays the role of operator as well as observer. To a large extent, the normal behavior in the normal environment can also be thought of in these same terms. Taking liberties with Shakespeare, it might be said, all the world's a display and all the individuals in it are operators in and on the display. Within this general context of interactive display systems, a discussion is began with a conceptual overview of a particular class of such systems, namely, teleoperator systems. The notion is considered of telepresence and the factors that limit telepresence, including decorrelation between the: (1) motor output of the teleoperator as sensed directly via the kinesthetic/tactual system, and (2) the motor output of the teleoperator as sensed indirectly via feedback from the slave robot, i.e., via a visual display of the motor actions of the slave robot. Finally, the deleterious effect of time delay (a particular decorrelation) on sensory-motor adaptation (an important phenomenon related to telepresence) is examined.

  19. Delayed feedback control of self-mobile cavity solitons

    NASA Astrophysics Data System (ADS)

    Pimenov, A.; Vladimirov, A. G.; Gurevich, S. V.; Panajotov, K.; Huyet, G.; Tlidi, M.

    2013-11-01

    Control of the motion of cavity solitons is one the central problems in nonlinear optical pattern formation. We report on the impact of the phase of the time-delayed optical feedback and carrier lifetime on the self-mobility of localized structures of light in broad-area semiconductor cavities. We show both analytically and numerically that the feedback phase strongly affects the drift instability threshold as well as the velocity of cavity soliton motion above this threshold. In addition we demonstrate that the noninstantaneous carrier response of the semiconductor medium is responsible for the increase of the critical feedback rate corresponding to the drift instability.

  20. Composite strongly interacting dark matter

    NASA Astrophysics Data System (ADS)

    Cline, James M.; Liu, Zuowei; Moore, Guy D.; Xue, Wei

    2014-07-01

    It has been suggested that cold dark matter (CDM) has difficulties in explaining tentative evidence for noncuspy halo profiles in small galaxies, and the low velocity dispersions observed in the largest Milky Way satellites ("too-big-to-fail" problem). Strongly self-interacting dark matter has been noted as a robust solution to these problems. The elastic cross sections required are much larger than predicted by generic CDM models, but could naturally be of the right size if dark matter is composite. We explore in a general way the constraints on models where strongly interacting CDM is in the form of dark "atoms" or "molecules," or bound states of a confining gauge interaction ("hadrons"). These constraints include considerations of relic density, direct detection, big bang nucleosynthesis, the cosmic microwave background, and LHC data.

  1. Do the Adjusting- and Increasing-Delay Tasks Measure the Same Construct – Delay Discounting?

    PubMed Central

    Craig, Andrew R.; Maxfield, Adam D.; Stein, Jeffrey S.; Renda, C. Renee; Madden, Gregory J.

    2014-01-01

    Delay discounting describes the subjective devaluation of a reward when it is delayed. In animals, the adjusting- and increasing-delay tasks often are used to assess individual differences in, and drug effects on, delay discounting. No study to date, however, has compared systematically the measures of discounting produced in these tasks. The current study examined the correlation between measures of delay discounting derived from adjusting- and increasing-delay procedures. Twenty rats completed 30 sessions under each task (order counterbalanced across rats). Quantitative measures of delay discounting produced by the two tasks were positively correlated, suggesting that the adjusting-and increasing-delay tasks measure the same underlying facet of impulsive choice (i.e., individual or conjoint sensitivities to reward delay and magnitude). The measures derived from either task, however, depended on the sequences in which the tasks were experienced. That is, pre-exposure to one task decreased discounting of delayed rewards in the second task. Consistent with other published findings, exposure to delayed consequences during the initial discounting assessment might explain this effect. Despite the observed correlation between ID and AD indifference delays, we suggest that the ID procedure might be a more appropriate procedure for pharmacological studies. PMID:24978484

  2. 49 CFR 236.831 - Time, delay.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Time, delay. 236.831 Section 236.831 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Time, delay. As applied to an automatic train stop or train control system, the time which...

  3. 49 CFR 236.831 - Time, delay.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Time, delay. 236.831 Section 236.831 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Time, delay. As applied to an automatic train stop or train control system, the time which...

  4. Delaying Developmental Mathematics: The Characteristics and Costs

    ERIC Educational Resources Information Center

    Johnson, Marianne; Kuennen, Eric

    2004-01-01

    This paper investigates which students delay taking a required developmental mathematics course and the impact of delay on student performance in introductory microeconomics. Analysis of a sample of 1462 students at a large Midwestern university revealed that, although developmental-level mathematics students did not reach the same level of…

  5. On Delay and Security in Network Coding

    ERIC Educational Resources Information Center

    Dikaliotis, Theodoros K.

    2013-01-01

    In this thesis, delay and security issues in network coding are considered. First, we study the delay incurred in the transmission of a fixed number of packets through acyclic networks comprised of erasure links. The two transmission schemes studied are routing with hop-by-hop retransmissions, where every node in the network simply stores and…

  6. Test Anxiety and Academic Delay of Gratification

    ERIC Educational Resources Information Center

    Bembenutty, Hefer

    2009-01-01

    The present study examined the relationship between college students' willingness to delay gratification, motivation, self-regulation of learning, and their level of test anxiety (N = 364). Academic delay of gratification refers to students' postponement of immediately available opportunities to satisfy impulses in favor of pursuing academic…

  7. 49 CFR 236.831 - Time, delay.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Time, delay. 236.831 Section 236.831 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Time, delay. As applied to an automatic train stop or train control system, the time which...

  8. Minimizing the Delay at Traffic Lights

    ERIC Educational Resources Information Center

    Van Hecke, Tanja

    2009-01-01

    Vehicles holding at traffic lights is a typical queuing problem. At crossings the vehicles experience delay in both directions. Longer periods with green lights in one direction are disadvantageous for the vehicles coming from the other direction. The total delay for getting through the traffic point is what counts. This article presents an…

  9. Discounting of Delayed Rewards Is Not Hyperbolic

    ERIC Educational Resources Information Center

    Luhmann, Christian C.

    2013-01-01

    Delay discounting refers to decision-makers' tendency to value immediately available goods more than identical goods available only after some delay. In violation of standard economic theory, decision-makers frequently exhibit dynamic inconsistency; their preferences change simply due to the passage of time. The standard explanation for this…

  10. Government delays release of medical marijuana supply.

    PubMed

    Scanlon, Liz

    2002-07-01

    The federal government's initiative to make marijuana available for medical use continues to run into problems and delays. In a recent development, the first crop produced by the government's designated grower turned out to be too impure to use. The delays have led to the launch of a lawsuit against the federal government. PMID:14765485

  11. 78 FR 51819 - List of Applications Delayed

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ... Pipeline and Hazardous Materials Safety Administration List of Applications Delayed AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), DOT. ACTION: List of applications delayed more than 180... following list of special permit applications that have been in process for 180 days or more. The...

  12. 78 FR 36820 - List of Applications Delayed

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-19

    ... Pipeline and Hazardous Materials Safety Administration List of Applications Delayed AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), DOT. ACTION: List of applications delayed more than 180... following list of special permit applications that have been in process for 180 days or more. The...

  13. 49 CFR 236.831 - Time, delay.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Time, delay. 236.831 Section 236.831 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Time, delay. As applied to an automatic train stop or train control system, the time which...

  14. 49 CFR 236.831 - Time, delay.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Time, delay. 236.831 Section 236.831 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Time, delay. As applied to an automatic train stop or train control system, the time which...

  15. Delaying gratification depends on social trust

    PubMed Central

    Michaelson, Laura; de la Vega, Alejandro; Chatham, Christopher H.; Munakata, Yuko

    2013-01-01

    Delaying gratification is hard, yet predictive of important life outcomes, such as academic achievement and physical health. Prominent theories focus on the role of self-control, hypersensitivity to immediate rewards, and the cost of time spent waiting. However, delaying gratification may also require trust in people delivering future rewards as promised. To test the role of social trust, participants were presented with character vignettes and faces that varied in trustworthiness, and then choose between hypothetical smaller immediate or larger delayed rewards from those characters. Across two experiments, participants were less willing to wait for delayed rewards from less trustworthy characters, and perceived trustworthiness predicted willingness to delay gratification. These findings provide the first demonstration of a causal role for social trust in willingness to delay gratification, independent of other relevant factors, such as self-control or reward history. Thus, delaying gratification requires choosing not only a later reward, but a reward that is potentially less likely to be delivered, when there is doubt about the person promising it. Implications of this work include the need to revise prominent theories of delay of gratification, and new directions for interventions with populations characterized by impulsivity. PMID:23801977

  16. Control of Telerobots with Variable Communication Delay

    NASA Technical Reports Server (NTRS)

    Oboe, R.; Fiorini, P.

    1998-01-01

    Ths paper proposes two solutions for the control of telerobots, in which master and slave are connected through a communication system that introduces a variable delay. This is the typical case of packet-switched networks (e.g. Internet), in which the delay varies in an unpredictible way.

  17. Delayed biodiversity change: no time to waste.

    PubMed

    Essl, Franz; Dullinger, Stefan; Rabitsch, Wolfgang; Hulme, Philip E; Pyšek, Petr; Wilson, John R U; Richardson, David M

    2015-07-01

    Delayed biodiversity responses to environmental forcing mean that rates of contemporary biodiversity changes are underestimated, yet these delays are rarely addressed in conservation policies. Here, we identify mechanisms that lead to such time lags, discuss shifting human perceptions, and propose how these phenomena should be addressed in biodiversity management and science. PMID:26028440

  18. Delayed gastric emptying in Parkinson's disease.

    PubMed

    Marrinan, Sarah; Emmanuel, Anton V; Burn, David J

    2014-01-01

    Gastrointestinal symptoms are evident in all stages of Parkinson's disease (PD). Most of the gastrointestinal abnormalities associated with PD are attributable to impaired motility. At the level of the stomach, this results in delayed gastric emptying. The etiology of delayed gastric emptying in PD is probably multifactorial but is at least partly related to Lewy pathology in the enteric nervous system and discrete brainstem nuclei. Delayed gastric emptying occurs in both early and advanced PD but is underdetected in routine clinical practice. Recognition of delayed gastric emptying is important because it can cause an array of upper gastrointestinal symptoms, but additionally it has important implications for the absorption and action of levodopa. Delayed gastric emptying contributes significantly to response fluctuations seen in people on long-term l-dopa therapy. Neurohormonal aspects of the brain-gut axis are pertinent to discussions regarding the pathophysiology of delayed gastric emptying in PD and are also hypothesized to contribute to the pathogenesis of PD itself. Ghrelin is a gastric-derived hormone with potential as a therapeutic agent for delayed gastric emptying and also as a novel neuroprotective agent in PD. Recent findings relating to ghrelin in the context of PD and gastric emptying are considered. This article highlights the pathological abnormalities that may account for delayed gastric emptying in PD. It also considers the wider relevance of abnormal gastric pathology to our current understanding of the etiology of PD. PMID:24151126

  19. Speech Delay: Its Treatment by Speech Play.

    ERIC Educational Resources Information Center

    Craft, Michael

    Directed to parents, the text discusses normal and delayed speech development and considers the causes of delay. Suggestions are given for helping deaf, emotionally disturbed, brain damaged, and physically handicapped children. Additional suggestions are provided for parents of twins, of stutterers, and of mongoloid or multiply handicapped…

  20. Delay synchronization of temporal Boolean networks

    NASA Astrophysics Data System (ADS)

    Wei, Qiang; Xie, Cheng-jun; Liang, Yi; Niu, Yu-jun; Lin, Da

    2016-01-01

    This paper investigates the delay synchronization between two temporal Boolean networks base on semi-tensor product method, which improve complete synchronization. Necessary and sufficient conditions for delay synchronization are drawn base on algebraic expression of temporal Boolean networks. A example is presented to show the effectiveness of theoretical analysis.

  1. 34 CFR 303.10 - Developmental delay.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 2 2011-07-01 2010-07-01 true Developmental delay. 303.10 Section 303.10 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND... DISABILITIES General Purpose, Eligibility, and Other General Provisions § 303.10 Developmental delay. As...

  2. Strongly interacting parton matter equilibration

    SciTech Connect

    Ozvenchuk, V.; Linnyk, O.; Bratkovskaya, E.; Gorenstein, M.; Cassing, W.

    2012-07-15

    We study the kinetic and chemical equilibration in 'infinite' parton matter within the Parton-Hadron-String Dynamics transport approach. The 'infinite' matter is simulated within a cubic box with periodic boundary conditions initialized at different energy densities. Particle abundances, kinetic energy distributions, and the detailed balance of the off-shell quarks and gluons in the strongly-interacting quarkgluon plasma are addressed and discussed.

  3. Strong CP and SUZ2

    NASA Astrophysics Data System (ADS)

    Albaid, Abdelhamid; Dine, Michael; Draper, Patrick

    2015-12-01

    Solutions to the strong CP problem typically introduce new scales associated with the spontaneous breaking of symmetries. Absent any anthropic argument for small overline{θ} , these scales require stabilization against ultraviolet corrections. Supersymmetry offers a tempting stabilization mechanism, since it can solve the "big" electroweak hierarchy problem at the same time. One family of solutions to strong CP, including generalized parity models, heavy axion models, and heavy η' models, introduces {Z}_2 copies of (part of) the Standard Model and an associated scale of {Z}_2 -breaking. We review why, without additional structure such as supersymmetry, the {Z}_2 -breaking scale is unacceptably tuned. We then study "SUZ2" models, supersymmetric theories with {Z}_2 copies of the MSSM. We find that the addition of SUSY typically destroys the {Z}_2 protection of overline{θ}=0 , even at tree level, once SUSY and {Z}_2 are broken. In theories like supersymmetric completions of the twin Higgs, where {Z}_2 addresses the little hierarchy problem but not strong CP, two axions can be used to relax overline{θ}.

  4. Discounting of delayed rewards: (A)theoretical interpretation of the Kirby questionnaire.

    PubMed

    Myerson, Joel; Baumann, Ana A; Green, Leonard

    2014-09-01

    111 Participants, recruited from Amazon's MTurk worker pool, completed Kirby's (2009) monetary choice questionnaire, which involves choosing between immediate, but smaller rewards and delayed, but larger rewards. Individual participants' responses were scored in three ways: first, by calculating the proportion of choices of the delayed rewards; second; using the scoring procedure described by Kirby et al. (1999) to estimate discounting rate (i.e., the value of the k-parameter in a hyperbolic discounting function); and third, using logistic regression to estimate discounting rate (Wileyto et al., 2004). Individuals' scores calculated using the proportion measure and the logarithms of their estimated k values were very strongly correlated (rs>.97). In addition, the proportions of choices of small, medium, and large amounts of the delayed rewards were strongly correlated (rs>.80). Taken together, these results suggest that the relative ease of calculating the proportion measure does not require sacrificing reliability. Moreover, the proportion measure is atheoretical and very easy to calculate whereas estimating an individual's discounting rate requires assuming a theoretical model that may not be appropriate. Significant differences in the proportion of delayed reward choices were observed between the small, medium, and large delayed reward amounts, with smaller rewards being discounted more steeply than larger ones, replicating previous findings of magnitude effects. These results provide further validation of the proportion of delayed reward choices on the Kirby questionnaire as a measure of individual and group differences in discounting. PMID:25139835

  5. Experimental study of high-energy fractures delayed operation in promote bone healing

    PubMed Central

    Pan, Zhi-Jun; Li, Zhong; Li, Jing

    2015-01-01

    To investigate role of delayed operation to stimulate growth of strong external callus in high-energy fractures, and explore a new way for bone healing. Twenty adult dogs were employed, and randomly divided into four groups, including group A-D. The dogs underwent osteotomy by wire saw in middle of femur, electric coagulation damaged surrounding periosteum, forming a 1 cm defect. Group A were internal fixed 14 days after osteotomy (higher-energy fractures delayed operation), Group B and C were internal fixed immediately (no delayed operation), Group D were internal fixed 14 days after osteotomy (delayed operation, but resected granulations around extremities). The results showed that groups of early fixed have no external callus growth and almost no growth in internal callus, these conditions leads to atrophy nonunion. On contrary, the porosis was strong and callus union was steady in group A and D, which have a delayed operation. In conclusion, early surgical fixation of high-energy fracture restrains external callus growth, easily lead to poor callus healing phenomenon of low-quality. Delayed surgical fixation can begin to repair soft tissues injury, stimulate external callus growth and improve fracture healing, so a small incision open reduction produce more robust growth effect than closed reduction. PMID:26379852

  6. Effects of elongation delay in transcription dynamics.

    PubMed

    Zhang, Xuan; Jin, Huiqin; Yang, Zhuoqin; Lei, Jinzhi

    2014-12-01

    In the transcription process, elongation delay is induced by the movement of RNA polymerases (RNAP) along the DNA sequence, and can result in changes in the transcription dynamics. This paper studies the transcription dynamics that involved the elongation delay and effects of cell division and DNA replication. The stochastic process of gene expression is modeled with delay chemical master equation with periodic coefficients, and is studied numerically through the stochastic simulation algorithm with delay. We show that the average transcription level approaches to a periodic dynamics over cell cycles at homeostasis, and the elongation delay can reduce the transcription level and increase the transcription noise. Moreover, the transcription elongation can induce bimodal distribution of mRNA levels that can be measured by the techniques of flow cytometry. PMID:25365608

  7. Switching control and time-delay identification

    NASA Astrophysics Data System (ADS)

    Chen, Qi; Li, Xiang; Qin, Zhi-Chang; Zhong, Shun; Sun, J. Q.

    2014-12-01

    The unknown time delay makes the control design a difficult task. When the lower and upper bounds of an unknown time delay of dynamical systems are specified, one can design a supervisory control that switches among a set of controls designed for the sampled time delays in the given range so that the closed-loop system is stable and the control performance is maintained at a desirable level. In this paper, we propose to design a supervisory control to stabilize the system first. After the supervisory control converges, we start an algorithm to identify the unknown time delay, either on-line or off-line, with the known control being implemented. Examples are shown to demonstrate the stabilization and identification for linear time invariant and periodic systems with a single control time delay.

  8. Strong interactive massive particles from a strong coupled theory

    SciTech Connect

    Khlopov, Maxim Yu.; Kouvaris, Chris

    2008-03-15

    Minimal walking technicolor models can provide a nontrivial solution for cosmological dark matter, if the lightest technibaryon is doubly charged. Technibaryon asymmetry generated in the early Universe is related to baryon asymmetry, and it is possible to create an excess of techniparticles with charge (-2). These excessive techniparticles are all captured by {sup 4}He, creating techni-O-helium tOHe atoms, as soon as {sup 4}He is formed in big bang nucleosynthesis. The interaction of techni-O-helium with nuclei opens new paths to the creation of heavy nuclei in big bang nucleosynthesis. Because of the large mass of technibaryons, the tOHe ''atomic'' gas decouples from the baryonic matter and plays the role of dark matter in large scale structure formation, while structures in small scales are suppressed. Nuclear interactions with matter slow down cosmic techni-O-helium in the Earth below the threshold of underground dark matter detectors, thus escaping severe cryogenic dark matter search constraints. On the other hand, these nuclear interactions are not sufficiently strong to exclude this form of strongly interactive massive particles by constraints from the XQC experiment. Experimental tests of this hypothesis are possible in the search for tOHe in balloon-borne experiments (or on the ground) and for its charged techniparticle constituents in cosmic rays and accelerators. The tOHe atoms can cause cold nuclear transformations in matter and might form anomalous isotopes, offering possible ways to exclude (or prove?) their existence.

  9. Risk factors for delay in symptomatic presentation: a survey of cancer patients

    PubMed Central

    Forbes, L J L; Warburton, F; Richards, M A; Ramirez, A J

    2014-01-01

    Background: Delay in symptomatic presentation leading to advanced stage at diagnosis may contribute to poor cancer survival. To inform public health approaches to promoting early symptomatic presentation, we aimed to identify risk factors for delay in presentation across several cancers. Methods: We surveyed 2371 patients with 15 cancers about nature and duration of symptoms using a postal questionnaire. We calculated relative risks for delay in presentation (time from symptom onset to first presentation >3 months) by cancer, symptoms leading to diagnosis and reasons for putting off going to the doctor, controlling for age, sex and deprivation group. Results: Among 1999 cancer patients reporting symptoms, 21% delayed presentation for >3 months. Delay was associated with greater socioeconomic deprivation but not age or sex. Patients with prostate (44%) and rectal cancer (37%) were most likely to delay and patients with breast cancer least likely to delay (8%). Urinary difficulties, change of bowel habit, systemic symptoms (fatigue, weight loss and loss of appetite) and skin symptoms were all common and associated with delay. Overall, patients with bleeding symptoms were no more likely to delay presentation than patients who did not have bleeding symptoms. However, within the group of patients with bleeding symptoms, there were significant differences in risk of delay by source of bleeding: 35% of patients with rectal bleeding delayed presentation, but only 9% of patients with urinary bleeding. A lump was a common symptom but not associated with delay in presentation. Twenty-eight percent had not recognised their symptoms as serious and this was associated with a doubling in risk of delay. Embarrassment, worry about what the doctor might find, being too busy to go to the doctor and worry about wasting the doctor's time were also strong risk factors for delay, but were much less commonly reported (<6%). Interpretation: Approaches to promote early presentation should

  10. Mitochondrial respiratory complex I probed by delayed luminescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Baran, Irina; Ionescu, Diana; Privitera, Simona; Scordino, Agata; Mocanu, Maria Magdalena; Musumeci, Francesco; Grasso, Rosaria; Gulino, Marisa; Iftime, Adrian; Tofolean, Ioana Teodora; Garaiman, Alexandru; Goicea, Alexandru; Irimia, Ruxandra; Dimancea, Alexandru; Ganea, Constanta

    2013-12-01

    The role of mitochondrial complex I in ultraweak photon-induced delayed photon emission [delayed luminescence (DL)] of human leukemia Jurkat T cells was probed by using complex I targeting agents like rotenone, menadione, and quercetin. Rotenone, a complex I-specific inhibitor, dose-dependently increased the mitochondrial level of reduced nicotinamide adenine dinucleotide (NADH), decreased clonogenic survival, and induced apoptosis. A strong correlation was found between the mitochondrial levels of NADH and oxidized flavin mononucleotide (FMNox) in rotenone-, menadione- and quercetin-treated cells. Rotenone enhanced DL dose-dependently, whereas quercetin and menadione inhibited DL as well as NADH or FMNox. Collectively, the data suggest that DL of Jurkat cells originates mainly from mitochondrial complex I, which functions predominantly as a dimer and less frequently as a tetramer. In individual monomers, both pairs of pyridine nucleotide (NADH/reduced nicotinamide adenine dinucleotide phosphate) sites and flavin (FMN-a/FMN-b) sites appear to bind cooperatively their specific ligands. Enhancement of delayed red-light emission by rotenone suggests that the mean time for one-electron reduction of ubiquinone or FMN-a by the terminal Fe/S center (N2) is 20 or 284 μs, respectively. All these findings suggest that DL spectroscopy could be used as a reliable, sensitive, and robust technique to probe electron flow within complex I in situ.

  11. Advanced access: reducing waiting and delays in primary care.

    PubMed

    Murray, Mark; Berwick, Donald M

    2003-02-26

    Delay of care is a persistent and undesirable feature of current health care systems. Although delay seems to be inevitable and linked to resource limitations, it often is neither. Rather, it is usually the result of unplanned, irrational scheduling and resource allocation. Application of queuing theory and principles of industrial engineering, adapted appropriately to clinical settings, can reduce delay substantially, even in small practices, without requiring additional resources. One model, sometimes referred to as advanced access, has increasingly been shown to reduce waiting times in primary care. The core principle of advanced access is that patients calling to schedule a physician visit are offered an appointment the same day. Advanced access is not sustainable if patient demand for appointments is permanently greater than physician capacity to offer appointments. Six elements of advanced access are important in its application balancing supply and demand, reducing backlog, reducing the variety of appointment types, developing contingency plans for unusual circumstances, working to adjust demand profiles, and increasing the availability of bottleneck resources. Although these principles are powerful, they are counter to deeply held beliefs and established practices in health care organizations. Adopting these principles requires strong leadership investment and support. PMID:12597760

  12. Spatiotemporal Brain Maps of Delayed Word Repetition and Recognition

    PubMed Central

    Dhond, Rupali P.; Witzel, Thomas; Dale, Anders M.; Halgren, Eric

    2006-01-01

    Whole-head magnetoencephalography (MEG) was used to spatiotemporally map the brain response underlying episodic retrieval of words studied a single time following a long delay (~40min.) Recognition following a long delay occurs as a strong, sustained, differential response, within bilateral, ventral and lateral prefrontal cortex, anterior temporal and medial parietal regions from ~500ms onward, as well as ventral occipitotemporal regions from ~700ms onward. In comparison with previous tasks using multiple repetitions at short delays, these effects were centered within the same areas (anteroventral temporal and ventral prefrontal), but were shifted to longer latencies (~500ms vs. ~200ms), were less left-lateralized, and appear more in anterolateral prefrontal regions and less in lateral temporal cortex. Furthermore, comparison of correctly classified words with misclassified, novel and repeated words, suggests that these frontotemporal-parietocingulate responses are sensitive to actual as well as perceived repetition. The results also suggest that lateral prefrontal regions may participate more in controlled, effortful retrieval while left ventral frontal and anterior temporal responses may support sustained lexicosemantic processing. Additionally, left ventromedial temporal sites may be relatively more involved in episodic retrieval, while lateral temporal sites may participate more in automatic priming. PMID:16084111

  13. Syneresis and delayed detachment in agar plates.

    PubMed

    Divoux, Thibaut; Mao, Bosi; Snabre, Patrick

    2015-05-14

    Biogels made of crosslinked polymers such as proteins or polysaccharides behave as porous soft solids and store large amounts of solvent. These gels undergo spontaneous aging, called syneresis, which consists of the shrinkage of the gel matrix and the progressive expulsion of solvent. As a result, a biogel originally casted in a container often loses contact with the container sidewalls, and the detachment time is difficult to anticipate a priori, since it may occur over variable time spans (from hours to days). Here we report on syneresis phenomena in agar plates, which consist of Petri dishes filled with a gel mainly composed of agar. Direct observations and speckle pattern correlation analysis allow us to rationalize the delayed detachment of the gel from the sidewall of the Petri dish. The detachment time t* is surprisingly not controlled by the mass loss as one would intuitively expect. Instead, t* is strongly correlated to the gel minimum thickness emin measured along the sidewall of the plate, and increases as a robust function of emin, independently of the prior mass-loss history. Time-resolved correlation spectroscopy atypically applied to such weakly diffusive media gives access to the local thinning rate of the gel. This technique also allows us to detect the gel micro-displacements that are triggered by water evaporation prior to the detachment, and even to anticipate the latter from a few hours. Our work provides observables to predict the detachment time of agar gels in dishes, and highlights the relevance of speckle pattern correlation analysis for the quantitative investigation of the syneresis dynamics in biopolymer gels. PMID:25812667

  14. Dynamics of Time Delay-Induced Multiple Synchronous Behaviors in Inhibitory Coupled Neurons

    PubMed Central

    Gu, Huaguang; Zhao, Zhiguo

    2015-01-01

    The inhibitory synapse can induce synchronous behaviors different from the anti-phase synchronous behaviors, which have been reported in recent studies. In the present paper, synchronous behaviors are investigated in the motif model composed of reciprocal inhibitory coupled neurons with endogenous bursting and time delay. When coupling strength is weak, synchronous behavior appears at a single interval of time delay within a bursting period. When coupling strength is strong, multiple synchronous behaviors appear at different intervals of time delay within a bursting period. The different bursting patterns of synchronous behaviors, and time delays and coupling strengths that can induce the synchronous bursting patterns can be well interpreted by the dynamics of the endogenous bursting pattern of isolated neuron, which is acquired by the fast-slow dissection method, combined with the inhibitory coupling current. For an isolated neuron, when a negative impulsive current with suitable strength is applied at different phases of the bursting, multiple different bursting patterns can be induced. For a neuron in the motif, the inhibitory coupling current, of which the application time and strength is modulated by time delay and coupling strength, can cause single or multiple synchronous firing patterns like the negative impulsive current when time delay and coupling strength is suitable. The difference compared to the previously reported multiple synchronous behaviors that appear at time delays wider than a period of the endogenous firing is discussed. The results present novel examples of synchronous behaviors in the neuronal network with inhibitory synapses and provide a reasonable explanation. PMID:26394224

  15. Persistent Language Delay Versus Late Language Emergence in Children With Early Cochlear Implantation

    PubMed Central

    Nicholas, Johanna; Tobey, Emily; Davidson, Lisa

    2016-01-01

    Purpose The purpose of the present investigation is to differentiate children using cochlear implants (CIs) who did or did not achieve age-appropriate language scores by midelementary grades and to identify risk factors for persistent language delay following early cochlear implantation. Materials and Method Children receiving unilateral CIs at young ages (12–38 months) were tested longitudinally and classified with normal language emergence (n = 19), late language emergence (n = 22), or persistent language delay (n = 19) on the basis of their test scores at 4.5 and 10.5 years of age. Relative effects of demographic, audiological, linguistic, and academic characteristics on language emergence were determined. Results Age at CI was associated with normal language emergence but did not differentiate late emergence from persistent delay. Children with persistent delay were more likely to use left-ear implants and older speech processor technology. They experienced higher aided thresholds and lower speech perception scores. Persistent delay was foreshadowed by low morphosyntactic and phonological diversity in preschool. Logistic regression analysis predicted normal language emergence with 84% accuracy and persistent language delay with 74% accuracy. Conclusion CI characteristics had a strong effect on persistent versus resolving language delay, suggesting that right-ear (or bilateral) devices, technology upgrades, and improved audibility may positively influence long-term language outcomes. PMID:26501740

  16. Trading Later Rewards for Current Pleasure: Pornography Consumption and Delay Discounting.

    PubMed

    Negash, Sesen; Sheppard, Nicole Van Ness; Lambert, Nathaniel M; Fincham, Frank D

    2016-01-01

    Internet pornography is a multi-billion-dollar industry that has grown increasingly accessible. Delay discounting involves devaluing larger, later rewards in favor of smaller, more immediate rewards. The constant novelty and primacy of sexual stimuli as particularly strong natural rewards make Internet pornography a unique activator of the brain's reward system, thereby having implications for decision-making processes. Based on theoretical studies of evolutionary psychology and neuroeconomics, two studies tested the hypothesis that consuming Internet pornography would relate to higher rates of delay discounting. Study 1 used a longitudinal design. Participants completed a pornography use questionnaire and a delay discounting task at Time 1 and then again four weeks later. Participants reporting higher initial pornography use demonstrated a higher delay discounting rate at Time 2, controlling for initial delay discounting. Study 2 tested for causality with an experimental design. Participants were randomly assigned to abstain from either their favorite food or pornography for three weeks. Participants who abstained from pornography use demonstrated lower delay discounting than participants who abstained from their favorite food. The finding suggests that Internet pornography is a sexual reward that contributes to delay discounting differently than other natural rewards. Theoretical and clinical implications of these studies are highlighted. PMID:26305628

  17. Space Shuttle Propulsion Finishing Strong

    NASA Technical Reports Server (NTRS)

    Owen, James W.; Singer, Jody

    2011-01-01

    Numerous lessons have been documented from the Space Shuttle Propulsion elements. Major events include loss of the SRB's on STS-4 and shutdown of an SSME during ascent on STS- 51F. On STS-112 only half the pyrotechnics fired to release the vehicle from the launch pad, a testament for redundancy. STS-91 exhibited freezing of a main combustion chamber pressure measurement and on STS-93 nozzle tube ruptures necessitated a low liquid level oxygen cut off of the main engines. A number of on pad aborts were experienced during the early program resulting in delays. And the two accidents, STS-51L and STS-107, had unique heritage in history from early Program decisions and vehicle configuration. Following STS-51L significant resources were invested in developing fundamental physical understanding of solid rocket motor environments and material system behavior. Human rating of solid rocket motors was truly achieved. And following STS-107, the risk of ascent debris was better characterized and controlled. Situational awareness during all mission phases improved, and the management team instituted effective risk assessment practices. These major events and lessons for the future are discussed. The last 22 flights of the Space Shuttle, following the Columbia accident, were characterized by remarkable improvement in safety and reliability. Numerous problems were solved in addition to reduction of the ascent debris hazard. The propulsion system elements evolved to high reliability and heavy lift capability. The Shuttle system, though not a operable as envisioned in the 1970's, successfully assembled the International Space Station (ISS) and provided significant logistics and down mass for ISS operations. By the end of the Program, the remarkable Space Shuttle Propulsion system achieved very high performance, was largely reusable, exhibited high reliability, and is a heavy lift earth to orbit propulsion system. The story of this amazing system is discussed in detail in the paper.

  18. PREFACE: Strongly correlated electron systems Strongly correlated electron systems

    NASA Astrophysics Data System (ADS)

    Saxena, Siddharth S.; Littlewood, P. B.

    2012-07-01

    This special section is dedicated to the Strongly Correlated Electron Systems Conference (SCES) 2011, which was held from 29 August-3 September 2011, in Cambridge, UK. SCES'2011 is dedicated to 100 years of superconductivity and covers a range of topics in the area of strongly correlated systems. The correlated electronic and magnetic materials featured include f-electron based heavy fermion intermetallics and d-electron based transition metal compounds. The selected papers derived from invited presentations seek to deepen our understanding of the rich physical phenomena that arise from correlation effects. The focus is on quantum phase transitions, non-Fermi liquid phenomena, quantum magnetism, unconventional superconductivity and metal-insulator transitions. Both experimental and theoretical work is presented. Based on fundamental advances in the understanding of electronic materials, much of 20th century materials physics was driven by miniaturisation and integration in the electronics industry to the current generation of nanometre scale devices. The achievements of this industry have brought unprecedented advances to society and well-being, and no doubt there is much further to go—note that this progress is founded on investments and studies in the fundamentals of condensed matter physics from more than 50 years ago. Nevertheless, the defining challenges for the 21st century will lie in the discovery in science, and deployment through engineering, of technologies that can deliver the scale needed to have an impact on the sustainability agenda. Thus the big developments in nanotechnology may lie not in the pursuit of yet smaller transistors, but in the design of new structures that can revolutionise the performance of solar cells, batteries, fuel cells, light-weight structural materials, refrigeration, water purification, etc. The science presented in the papers of this special section also highlights the underlying interest in energy-dense materials, which

  19. Delayed extinction fails to reduce skin conductance reactivity to fear-conditioned stimuli.

    PubMed

    Fricchione, Jon; Greenberg, Mark S; Spring, Justin; Wood, Nellie; Mueller-Pfeiffer, Christoph; Milad, Mohammed R; Pitman, Roger K; Orr, Scott P

    2016-09-01

    A brief 10-min time delay between an initial and subsequent exposure to extinction trials has been found to impair memory reconsolidation in fear-conditioned rodents and humans, providing a potential means to reduce fearfulness in anxiety disorders and posttraumatic stress disorder (PTSD). The present study used videos of biologically prepared, conditioned stimuli (tarantulas) to test the efficacy of delayed extinction in blocking reconsolidation of conditioned fear in healthy young adults. Strong differential conditioning, measured by skin conductance, was observed among a screened subset of participants during acquisition. However, the delayed-extinction intervention failed to reduce reactivity to the conditioned stimulus paired with the extinction delay. These results are partially consistent with other recent, mixed findings and point to a need for testing other candidate interventions designed to interfere with the reconsolidation process. PMID:27314560

  20. Influence of the circadian rhythm in cell division on radiation-induced mitotic delay in vivo

    SciTech Connect

    Rubin, N.H.

    1982-01-01

    Mitotic delay is described as a classical response to radiation; however, circadian rhythmicity in cell division in vivo has not been considered by many authors. The present study investigated the relation between fluctuations reported as mitotic delay and recovery in vivo and circadian oscillations in mitotic index in mouse corneal epithelium. One aspect involved single doses (approximately 600 rad) given to mice at different circadian stages. The normal circadian rhythm in cell division was never obliterated. Inhibition of mitosis was evident but unpredictable, ranging from 6 to 15 hr after irradiation. Recovery was evident only during the daily increase in mitotic index of controls. The classical interpretation of recovery from mitotic delay may be in an in vitro phenomenon not reflecting in vivo responses, which are apparently strongly circadian stage dependent. The second portion of the study demonstrated a dose-response effect on length of mitotic delay and, to a lesser extent, degree of recovery.

  1. Anomalous delayed loss of trapped D-D fusion products in TFTR

    SciTech Connect

    Zweben, S.J.; Darrow, D.S.; Fredrickson, E.D.; Mynick, H.E.

    1993-02-01

    A new anomalous delayed loss of D-D fusion products has been measured at the bottom of the TFRR vessel. This loss is delayed by [approximately] 0.2 sec with respect to the usual prompt first-orbit loss, and has a correspondingly lower energy, i.e. about half the fusion product birth energy. This loss process dominates the total fusion product loss measured 90[degrees] below the midplane for plasma currents. I[ge] 1.8 MA and major radii near R=2.45 m, e.g. for recent TFTR supershots. This delayed feature can occur without large coherent MED activity, although it can be strongly modulated by such activity. Several possible causes for this phenomenon are discussed, but no clear explanation for this delayed loss has yet been found.

  2. Anomalous delayed loss of trapped D-D fusion products in TFTR

    SciTech Connect

    Zweben, S.J.; Darrow, D.S.; Fredrickson, E.D.; Mynick, H.E.

    1993-02-01

    A new anomalous delayed loss of D-D fusion products has been measured at the bottom of the TFRR vessel. This loss is delayed by {approximately} 0.2 sec with respect to the usual prompt first-orbit loss, and has a correspondingly lower energy, i.e. about half the fusion product birth energy. This loss process dominates the total fusion product loss measured 90{degrees} below the midplane for plasma currents. I{ge} 1.8 MA and major radii near R=2.45 m, e.g. for recent TFTR supershots. This delayed feature can occur without large coherent MED activity, although it can be strongly modulated by such activity. Several possible causes for this phenomenon are discussed, but no clear explanation for this delayed loss has yet been found.

  3. PREFACE: Strongly Coupled Coulomb Systems

    NASA Astrophysics Data System (ADS)

    Fortov, Vladimir E.; Golden, Kenneth I.; Norman, Genri E.

    2006-04-01

    This special issue contains papers presented at the International Conference on Strongly Coupled Coulomb Systems (SCCS) which was held during the week of 20 24 June 2005 in Moscow, Russia. The Moscow conference was the tenth in a series of conferences. The previous conferences were organized as follows. 1977: Orleans-la-Source, France, as a NATO Advanced Study Institute on Strongly Coupled Plasmas (organized by Marc Feix and Gabor J Kalman) 1982: Les Houches, France (organized by Marc Baus and Jean-Pierre Hansen) 1986: Santa Cruz, California, USA (hosted by Forrest J Rogers and Hugh E DeWitt) 1989: Tokyo, Japan (hosted by Setsuo Ichimaru) 1992: Rochester, NY, USA (hosted by Hugh M Van Horn and Setsuo Ichimaru) 1995: Binz, Germany (hosted by Wolf Dietrich Kraeft and Manfred Schlanges) 1997: Boston, Massachusetts, USA (hosted by Gabor J Kalman) 1999: St Malo, France (hosted by Claude Deutsch and Bernard Jancovici) 2002: Santa Fe, New Mexico, USA (hosted by John F Benage and Michael S Murillo) After 1995 the name of the series was changed from `Strongly Coupled Plasmas' to the present name in order to extend the topics of the conferences. The planned frequency for the future is once every three years. The purpose of these conferences is to provide an international forum for the presentation and discussion of research accomplishments and ideas relating to a variety of plasma liquid and condensed matter systems, dominated by strong Coulomb interactions between their constituents. Strongly coupled Coulomb systems encompass diverse many-body systems and physical conditions. Each meeting has seen an evolution of topics and emphasis as new discoveries and new methods appear. This year, sessions were organized for invited presentations and posters on dense plasmas and warm matter, astrophysics and dense hydrogen, non-neutral and ultracold plasmas, dusty plasmas, condensed matter 2D and layered charged-particle systems, Coulomb liquids, and statistical theory of SCCS. Within

  4. Strong turbulence of plasma waves

    NASA Technical Reports Server (NTRS)

    Goldman, M. V.

    1984-01-01

    This paper reviews recent work related to modulational instability and wave envelope self-focusing in dynamical and statistical systems. After introductory remarks pertinent to nonlinear optics realizations of these effects, the author summarizes the status of the subject in plasma physics, where it has come to be called 'strong Langmuir turbulence'. The paper treats the historical development of pertinent concepts, analytical theory, numerical simulations, laboratory experiments, and spacecraft observations. The role of self-similar self-focusing Langmuir envelope wave packets is emphasized, both in the Zakharov equation model for the wave dynamics and in a statistical theory based on this dynamical model.

  5. [DNA knots and strong triviality].

    PubMed

    Torisu, Ichiro

    2009-06-01

    A circle embedded in 3-space without self-intersection is called a knot. A knot is a mathematical object according to topology. Knot theory studies how complicated a given knot is, or whether it is trivial. Any knot can be represented by a diagram with above and below information at the crossings. Then a knot obtained by replacing the information at one crossing is generally another knot. This operation is called a crossing change. A crossing change is an important notion in knot theory. In this article, we survey the strong triviality of knots, which is one of the multi-crossing changes. PMID:19530562

  6. Temporal-contextual processing in working memory: evidence from delayed cued recall and delayed free recall tests.

    PubMed

    Loaiza, Vanessa M; McCabe, David P

    2012-02-01

    Three experiments are reported that addressed the nature of processing in working memory by investigating patterns of delayed cued recall and free recall of items initially studied during complex and simple span tasks. In Experiment 1, items initially studied during a complex span task (i.e., operation span) were more likely to be recalled after a delay in response to temporal-contextual cues, relative to items from subspan and supraspan list lengths in a simple span task (i.e., word span). In Experiment 2, items initially studied during operation span were more likely to be recalled from neighboring serial positions during delayed free recall than were items studied during word span trials. Experiment 3 demonstrated that the number of attentional refreshing opportunities strongly predicts episodic memory performance, regardless of whether the information is presented in a spaced or massed format in a modified operation span task. The results indicate that the content-context bindings created during complex span trials reflect attentional refreshing opportunities that are used to maintain items in working memory. PMID:21948350

  7. Delayed chromosomal instability induced by DNA damage.

    PubMed Central

    Marder, B A; Morgan, W F

    1993-01-01

    DNA damage induced by ionizing radiation can result in gene mutation, gene amplification, chromosome rearrangements, cellular transformation, and cell death. Although many of these changes may be induced directly by the radiation, there is accumulating evidence for delayed genomic instability following X-ray exposure. We have investigated this phenomenon by studying delayed chromosomal instability in a hamster-human hybrid cell line by means of fluorescence in situ hybridization. We examined populations of metaphase cells several generations after expanding single-cell colonies that had survived 5 or 10 Gy of X rays. Delayed chromosomal instability, manifested as multiple rearrangements of human chromosome 4 in a background of hamster chromosomes, was observed in 29% of colonies surviving 5 Gy and in 62% of colonies surviving 10 Gy. A correlation of delayed chromosomal instability with delayed reproductive cell death, manifested as reduced plating efficiency in surviving clones, suggests a role for chromosome rearrangements in cytotoxicity. There were small differences in chromosome destabilization and plating efficiencies between cells irradiated with 5 or 10 Gy of X rays after a previous exposure to 10 Gy and cells irradiated only once. Cell clones showing delayed chromosomal instability had normal frequencies of sister chromatid exchange formation, indicating that at this cytogenetic endpoint the chromosomal instability was not apparent. The types of chromosomal rearrangements observed suggest that chromosome fusion, followed by bridge breakage and refusion, contributes to the observed delayed chromosomal instability. Images PMID:8413263

  8. Delayed feedback applied to breathing in humans

    NASA Astrophysics Data System (ADS)

    Janson, N. B.; Pototsky, A.; Parkes, C.

    2013-10-01

    We studied the response of healthy volunteers to the delayed feedback generated from the breathing signals. Namely, in the freely-breathing volunteers the breathing signal was recorded, delayed by τ seconds and fed back to the same volunteer in real time in the form of a visual and auditory stimulus of low intensity, i.e. the stimulus was crucially non-intrusive. In each case volunteers were instructed to breathe in the way which was most comfortable for them, and no explanation about the kind of applied stimulus was provided to them. Each volunteer experienced 10 different delay times ranging between 10% and 100% of the average breathing period without external stimulus. It was observed that in a significant proportion of subjects (11 out of 24) breathing was slowed down in the presence of delayed feedback with moderate delay. Also, in 6 objects out of 24 the delayed feedback was able to induce transition from nearly periodic to irregular breathing. These observations are consistent with the phenomena observed in numerical simulation of the models of periodic and chaotic self-oscillations with delays, and also in experiments with simpler self-oscillating systems.

  9. Attosecond Electron Wave Packet Dynamics in Strong Laser Fields

    SciTech Connect

    Johnsson, P.; Remetter, T.; Varju, K.; L'Huillier, A.; Lopez-Martens, R.; Valentin, C.; Balcou, Ph.; Kazamias, S.; Mauritsson, J.; Gaarde, M. B.; Schafer, K. J.; Mairesse, Y.; Wabnitz, H.; Salieres, P.

    2005-07-01

    We use a train of sub-200 attosecond extreme ultraviolet (XUV) pulses with energies just above the ionization threshold in argon to create a train of temporally localized electron wave packets. We study the energy transfer from a strong infrared (IR) laser field to the ionized electrons as a function of the delay between the XUV and IR fields. When the wave packets are born at the zero crossings of the IR field, a significant amount of energy ({approx}20 eV) is transferred from the field to the electrons. This results in dramatically enhanced above-threshold ionization in conditions where the IR field alone does not induce any significant ionization. Because both the energy and duration of the wave packets can be varied independently of the IR laser, they are valuable tools for studying and controlling strong-field processes.

  10. Systematic Decomposition of Strong Field Spectra using Optical Phase Matching

    NASA Astrophysics Data System (ADS)

    Walters, Zachary B.; Haxton, Daniel J.; McCurdy, C. William

    2015-05-01

    Strong field transient absorption experiments measure the absorption or emission of energy from a broadband excitation laser pulse in the presence of an intense second pulse. Varying the time delay between the two pulses allows the effects of the intense field to be measured, yielding an experimental observable which may have a highly nonlinear dependence upon the parameters of the two fields. We apply optical phase matching conditions to decompose transient absorption spectra calculated using a nonperturbative multi configuration time dependent Hartree Fock (MCTDHF) code into a sum of multiphoton components, clarifying the role of recently identified light induced states in strong field photoabsorption. These results give a straightforward means of interpreting nonperturbative time dependent calculations, and suggest experimental methods for achieving these and similar goals. Work at the University of California Davis was supported by US Department of Energy grant No. DESC0007182. Work at LBNL was supported by USDOE, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division.

  11. Development and validation of the Delaying Gratification Inventory

    PubMed Central

    Hoerger, Michael; Quirk, Stuart W.; Weed, Nathan C.

    2011-01-01

    Deficits in gratification delay are associated with a broad range of public health problems, such as obesity, risky sexual behavior, and substance abuse. However, six decades of research on the construct has progressed less quickly than might be hoped, largely due to measurement issues. Although past research implicates five domains of delay behavior, involving food, physical pleasures, social interactions, money, and achievement, no published measure to date has tapped all five components of the content domain. Existing measures have been criticized for limitations related to efficiency, reliability, and construct validity. Using an innovative Internet-mediated approach to survey construction, we developed the 35-item five-factor Delaying Gratification Inventory (DGI). Evidence from four studies and a large, diverse sample of respondents (N = 10,741) provided support for the psychometric properties of the measure. Specifically, scores on the DGI demonstrated strong internal consistency and test-retest reliability for the 35-item composite, each of the five domains, and a 10-item short-form. The five-factor structure fit the data well and had good measurement invariance across subgroups. Construct validity was supported by correlations with scores on closely-related self-control measures, behavioral ratings, Big Five personality trait measures, and measures of adjustment and psychopathology, including those on the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF). DGI scores also showed incremental validity in accounting for well-being and health-related variables. The present investigation holds implications for improving public health, accelerating future research on gratification delay, and facilitating survey construction research more generally by demonstrating the suitability of an Internet-mediated strategy. PMID:21480721

  12. EDITORIAL: Strongly correlated electron systems Strongly correlated electron systems

    NASA Astrophysics Data System (ADS)

    Ronning, Filip; Batista, Cristian

    2011-03-01

    Strongly correlated electrons is an exciting and diverse field in condensed matter physics. This special issue aims to capture some of that excitement and recent developments in the field. Given that this issue was inspired by the 2010 International Conference on Strongly Correlated Electron Systems (SCES 2010), we briefly give some history in order to place this issue in context. The 2010 International Conference on Strongly Correlated Electron Systems was held in Santa Fe, New Mexico, a reunion of sorts from the 1989 International Conference on the Physics of Highly Correlated Electron Systems that also convened in Santa Fe. SCES 2010—co-chaired by John Sarrao and Joe Thompson—followed the tradition of earlier conferences, in this century, hosted by Buzios (2008), Houston (2007), Vienna (2005), Karlsruhe (2004), Krakow (2002) and Ann Arbor (2001). Every three years since 1997, SCES has joined the International Conference on Magnetism (ICM), held in Recife (2000), Rome (2003), Kyoto (2006) and Karlsruhe (2009). Like its predecessors, SCES 2010 topics included strongly correlated f- and d-electron systems, heavy-fermion behaviors, quantum-phase transitions, non-Fermi liquid phenomena, unconventional superconductivity, and emergent states that arise from electronic correlations. Recent developments from studies of quantum magnetism and cold atoms complemented the traditional subjects and were included in SCES 2010. 2010 celebrated the 400th anniversary of Santa Fe as well as the birth of astronomy. So what's the connection to SCES? The Dutch invention of the first practical telescope and its use by Galileo in 1610 and subsequent years overturned dogma that the sun revolved about the earth. This revolutionary, and at the time heretical, conclusion required innovative combinations of new instrumentation, observation and mathematics. These same combinations are just as important 400 years later and are the foundation of scientific discoveries that were discussed

  13. Delayed visual maturation and lead pollution.

    PubMed

    Gulson, B L; Yui, L A; Howarth, D

    1998-12-11

    Three children were born in the Broken Hill Australia lead mining community with delayed visual maturation of the optic nerve (blindness) within a period of 19 months. Because of the association with the lead pollution, the delayed visual maturation was attributed to lead exposure of the fetus during pregnancy. Lead isotopic analyses of the shed deciduous teeth from the three children demonstrate that they were not exposed to increased levels of lead from a mining or any other source during pregnancy and the etiology of the delayed visual maturation must be sought elsewhere. PMID:9926437

  14. Gravitational lens time delays and gravitational waves

    SciTech Connect

    Frieman, J.A. Department of Astronomy Astrophysics, University of Chicago, Chicago, Illinois 60637 ); Harari, D.D.; Surpi, G.C. )

    1994-10-15

    Using Fermat's principle, we analyze the effects of very long wavelength gravitational waves upon the images of a gravitationally lensed quasar. We show that the lens equation in the presence of gravity waves is equivalent to that of a lens with a different alignment between source, deflector, and observer in the absence of gravity waves. Contrary to a recent claim, we conclude that measurements of time delays in gravitational lenses cannot serve as a method to detect or constrain a stochastic background of gravitational waves of cosmological wavelengths, because the wave-induced time delay is observationally indistinguishable from an intrinsic time delay due to the lens geometry.

  15. Delayed self-synchronization in homoclinic chaos

    NASA Astrophysics Data System (ADS)

    Arecchi, F. T.; Meucci, R.; Allaria, E.; di Garbo, A.; Tsimring, L. S.

    2002-04-01

    The chaotic spike train of a homoclinic dynamical system is self-synchronized by applying a time-delayed correction proportional to the laser output intensity. Due to the sensitive nature of the homoclinic chaos to external perturbations, stabilization of very long-periodic orbits is possible. On these orbits, the dynamics appears chaotic over a finite time, but then it repeats with a recurrence time that is slightly longer than the delay time. The effect, called delayed self-synchronization, displays analogies with neurodynamic events that occur in the buildup of long-term memories.

  16. Finite time stabilization of delayed neural networks.

    PubMed

    Wang, Leimin; Shen, Yi; Ding, Zhixia

    2015-10-01

    In this paper, the problem of finite time stabilization for a class of delayed neural networks (DNNs) is investigated. The general conditions on the feedback control law are provided to ensure the finite time stabilization of DNNs. Then some specific conditions are derived by designing two different controllers which include the delay-dependent and delay-independent ones. In addition, the upper bound of the settling time for stabilization is estimated. Under fixed control strength, discussions of the extremum of settling time functional are made and a switched controller is designed to optimize the settling time. Finally, numerical simulations are carried out to demonstrate the effectiveness of the obtained results. PMID:26264170

  17. Measuring angular diameter distances of strong gravitational lenses

    NASA Astrophysics Data System (ADS)

    Jee, I.; Komatsu, E.; Suyu, S. H.

    2015-11-01

    The distance-redshift relation plays a fundamental role in constraining cosmological models. In this paper, we show that measurements of positions and time delays of strongly lensed images of a background galaxy, as well as those of the velocity dispersion and mass profile of a lens galaxy, can be combined to extract the angular diameter distance of the lens galaxy. Physically, as the velocity dispersion and the time delay give a gravitational potential (GM/r) and a mass (GM) of the lens, respectively, dividing them gives a physical size (r) of the lens. Comparing the physical size with the image positions of a lensed galaxy gives the angular diameter distance to the lens. A mismatch between the exact locations at which these measurements are made can be corrected by measuring a local slope of the mass profile. We expand on the original idea put forward by Paraficz and Hjorth, who analyzed singular isothermal lenses, by allowing for an arbitrary slope of a power-law spherical mass density profile, an external convergence, and an anisotropic velocity dispersion. We find that the effect of external convergence cancels out when dividing the time delays and velocity dispersion measurements. We derive a formula for the uncertainty in the angular diameter distance in terms of the uncertainties in the observables. As an application, we use two existing strong lens systems, B1608+656 (zL=0.6304) and RXJ1131-1231 (zL=0.295), to show that the uncertainty in the inferred angular diameter distances is dominated by that in the velocity dispersion, σ2, and its anisotropy. We find that the current data on these systems should yield about 16% uncertainty in DA per object. This improves to 13% when we measure σ2 at the so-called sweet-spot radius. Achieving 7% is possible if we can determine σ2 with 5% precision.

  18. Strong field gravitational lensing by a charged Galileon black hole

    NASA Astrophysics Data System (ADS)

    Zhao, Shan-Shan; Xie, Yi

    2016-07-01

    Strong field gravitational lensings are dramatically disparate from those in the weak field by representing relativistic images due to light winds one to infinity loops around a lens before escaping. We study such a lensing caused by a charged Galileon black hole, which is expected to have possibility to evade no-hair theorem. We calculate the angular separations and time delays between different relativistic images of the charged Galileon black hole. All these observables can potentially be used to discriminate a charged Galileon black hole from others. We estimate the magnitudes of these observables for the closest supermassive black hole Sgr A*. The strong field lensing observables of the charged Galileon black hole can be close to those of a tidal Reissner-Nordström black hole or those of a Reissner-Nordström black hole. It will be helpful to distinguish these black holes if we can separate the outermost relativistic images and determine their angular separation, brightness difference and time delay, although it requires techniques beyond the current limit.

  19. Delay differential models in multimode laser dynamics: taking chromatic dispersion into account

    NASA Astrophysics Data System (ADS)

    Vladimirov, A. G.; Huyet, G.; Pimenov, A.

    2016-04-01

    A set of differential equations with distributed delay is derived for modeling of multimode ring lasers with intracavity chromatic dispersion. Analytical stability analysis of continuous wave regimes is performed and it is demonstrated that sufficiently strong anomalous dispersion can destabilize these regimes.

  20. [Delay in diagnosis of common variable immunodeficiency: a paradigmatic case report].

    PubMed

    Iebba, Filippo; Di Sora, Fiorella; Leti, Wilma; Montella, Tatiana; Corea, Francesco; Montella, Francesco

    2015-11-01

    This case report highlights the frequent delay in diagnosis of common variable immunodeficiency. The patient, 84 years old, had over 30 years of recurrent infections. At the first visit serum IgG were less than 134 mg/dl. From the review of previous examinations strong hypogammaglobulinemia was present for over 14 years. PMID:26668044

  1. Probability densities in strong turbulence

    NASA Astrophysics Data System (ADS)

    Yakhot, Victor

    2006-03-01

    In this work we, using Mellin’s transform combined with the Gaussian large-scale boundary condition, calculate probability densities (PDFs) of velocity increments P(δu,r), velocity derivatives P(u,r) and the PDF of the fluctuating dissipation scales Q(η,Re), where Re is the large-scale Reynolds number. The resulting expressions strongly deviate from the Log-normal PDF P(δu,r) often quoted in the literature. It is shown that the probability density of the small-scale velocity fluctuations includes information about the large (integral) scale dynamics which is responsible for the deviation of P(δu,r) from P(δu,r). An expression for the function D(h) of the multifractal theory, free from spurious logarithms recently discussed in [U. Frisch, M. Martins Afonso, A. Mazzino, V. Yakhot, J. Fluid Mech. 542 (2005) 97] is also obtained.

  2. Strongly Interacting Homogeneous Fermi Gases

    NASA Astrophysics Data System (ADS)

    Mukherjee, Biswaroop; Patel, Parth; Yan, Zhenjie; Struck, Julian; Zwierlein, Martin

    2016-05-01

    We present a homogeneous box potential for strongly interacting Fermi gases. The local density approximation (LDA) allows measurements on traditional inhomogeneous traps to observe a continuous distribution of Fermi gases in a single shot, but also suffer from a broadened response due to line-of-sight averaging over varying densities. We trap ultracold Fermionic (6 Li) in an optical homogeneous potential and characterize its flatness through in-situ tomography. A hybrid approach combining a cylindrical optical potential with a harmonic magnetic trap allows us to exploit the LDA and measure local RF spectra without requiring significant image reconstruction. We extract various quantities from the RF spectra such as the Tan's contact, and discuss further measurements of homogeneous Fermi systems under spin imbalance and finite temperature.

  3. Electrophoresis in strong electric fields.

    PubMed

    Barany, Sandor

    2009-01-01

    Two kinds of non-linear electrophoresis (ef) that can be detected in strong electric fields (several hundred V/cm) are considered. The first ("classical" non-linear ef) is due to the interaction of the outer field with field-induced ionic charges in the electric double layer (EDL) under conditions, when field-induced variations of electrolyte concentration remain to be small comparatively to its equilibrium value. According to the Shilov theory, the non-linear component of the electrophoretic velocity for dielectric particles is proportional to the cubic power of the applied field strength (cubic electrophoresis) and to the second power of the particles radius; it is independent of the zeta-potential but is determined by the surface conductivity of particles. The second one, the so-called "superfast electrophoresis" is connected with the interaction of a strong outer field with a secondary diffuse layer of counterions (space charge) that is induced outside the primary (classical) diffuse EDL by the external field itself because of concentration polarization. The Dukhin-Mishchuk theory of "superfast electrophoresis" predicts quadratic dependence of the electrophoretic velocity of unipolar (ionically or electronically) conducting particles on the external field gradient and linear dependence on the particle's size in strong electric fields. These are in sharp contrast to the laws of classical electrophoresis (no dependence of V(ef) on the particle's size and linear dependence on the electric field gradient). A new method to measure the ef velocity of particles in strong electric fields is developed that is based on separation of the effects of sedimentation and electrophoresis using videoimaging and a new flowcell and use of short electric pulses. To test the "classical" non-linear electrophoresis, we have measured the ef velocity of non-conducting polystyrene, aluminium-oxide and (semiconductor) graphite particles as well as Saccharomice cerevisiae yeast cells as a

  4. Strong shock implosion, approximate solution

    NASA Astrophysics Data System (ADS)

    Fujimoto, Y.; Mishkin, E. A.; Alejaldre, C.

    1983-01-01

    The self-similar, center-bound motion of a strong spherical, or cylindrical, shock wave moving through an ideal gas with a constant, γ= cp/ cv, is considered and a linearized, approximate solution is derived. An X, Y phase plane of the self-similar solution is defined and the representative curved of the system behind the shock front is replaced by a straight line connecting the mappings of the shock front with that of its tail. The reduced pressure P(ξ), density R(ξ) and velocity U1(ξ) are found in closed, quite accurate, form. Comparison with numerically obtained results, for γ= {5}/{3} and γ= {7}/{5}, is shown.

  5. Concurrent-schedule performance in transition: changeover delays and signaled reinforcer ratios.

    PubMed Central

    Krägeloh, Christian U; Davison, Michael

    2003-01-01

    Six pigeons were trained in experimental sessions that arranged six or seven components with various concurrent-schedule reinforcer ratios associated with each. The order of the components was determined randomly without replacement. Components lasted until the pigeons had received 10 reinforcers, and were separated by 10-s blackout periods. The component reinforcer ratios arranged in most conditions were 27:1, 9:1, 3:1, 1:1, 1:3, 1:9 and 1:27; in others, there were only six components, three of 27:1 and three of 1:27. In some conditions, each reinforcement ratio was signaled by a different red-yellow flash frequency, with the frequency perfectly correlated with the reinforcer ratio. Additionally, a changeover delay was arranged in some conditions, and no changeover delay in others. When component reinforcer ratios were signaled, sensitivity to reinforcement values increased from around 0.40 before the first reinforcer in a component to around 0.80 before the 10th reinforcer. When reinforcer ratios were not signaled, sensitivities typically increased from zero to around 0.40. Sensitivity to reinforcement was around 0.20 lower in no-changeover-delay conditions than in changeover-delay conditions, but increased in the former after exposure to changeover delays. Local analyses showed that preference was extreme towards the reinforced alternative for the first 25 s after reinforcement in changeover-delay conditions regardless of whether components were signaled or not. In no-changeover-delay conditions, preference following reinforcers was either absent, or, following exposure to changeover delays, small. Reinforcers have both local and long-term effects on preference. The former, but not the latter, is strongly affected by the presence of a changeover delay. Stimulus control may be more closely associated with longer-term, more molar, reinforcer effects. PMID:12696743

  6. Effect of phase response curve skew on synchronization with and without conduction delays.

    PubMed

    Canavier, Carmen C; Wang, Shuoguo; Chandrasekaran, Lakshmi

    2013-01-01

    A central problem in cortical processing including sensory binding and attentional gating is how neurons can synchronize their responses with zero or near-zero time lag. For a spontaneously firing neuron, an input from another neuron can delay or advance the next spike by different amounts depending upon the timing of the input relative to the previous spike. This information constitutes the phase response curve (PRC). We present a simple graphical method for determining the effect of PRC shape on synchronization tendencies and illustrate it using type 1 PRCs, which consist entirely of advances (delays) in response to excitation (inhibition). We obtained the following generic solutions for type 1 PRCs, which include the pulse-coupled leaky integrate and fire model. For pairs with mutual excitation, exact synchrony can be stable for strong coupling because of the stabilizing effect of the causal limit region of the PRC in which an input triggers a spike immediately upon arrival. However, synchrony is unstable for short delays, because delayed inputs arrive during a refractory period and cannot trigger an immediate spike. Right skew destabilizes antiphase and enables modes with time lags that grow as the conduction delay is increased. Therefore, right skew favors near synchrony at short conduction delays and a gradual transition between synchrony and antiphase for pairs coupled by mutual excitation. For pairs with mutual inhibition, zero time lag synchrony is stable for conduction delays ranging from zero to a substantial fraction of the period for pairs. However, for right skew there is a preferred antiphase mode at short delays. In contrast to mutual excitation, left skew destabilizes antiphase for mutual inhibition so that synchrony dominates at short delays as well. These pairwise synchronization tendencies constrain the synchronization properties of neurons embedded in larger networks. PMID:24376399

  7. Eikonal Scattering at Strong Coupling

    NASA Astrophysics Data System (ADS)

    Irizarry-Gelpi, Melvin Eloy

    The scattering of subatomic particles is a source of important physical phenomena. Decades of work have yielded many techniques for the computation of scattering amplitudes. Most of these techniques involve perturbative quantum field theory and thus apply only at weak coupling. Complementary to scattering is the formation of bound states, which are intrinsically nonperturbative. Regge theory arose in the late 1950s as an attempt to describe, with a single framework, both scattering and the formation of bound states. In Regge theory one obtains an amplitude with bound state poles after analytic continuation of a nonperturbative scattering amplitude, corresponding to a sum of an infinite number of Feynman diagrams at large energy and fixed momentum transfer (but with crossed kinematics). Thus, in order to obtain bound states at fixed energy, one computes an amplitude at large momentum transfer. In this dissertation we calculate amplitudes with bound states in the regime of fixed energy and small momentum transfer. We formulate the elastic scattering problem in terms of many-body path integrals, familiar from quantum mechanics. Then we invoke the semiclassical JWKB approximation, where the path integral is dominated by classical paths. The dynamics in the semiclassical regime are strongly coupled, as found by Halpern and Siegel. When the momentum transfer is small, the classical paths are simple straight lines and the resulting semiclassical amplitudes display a spectrum of bound states that agrees with the spectrum found by solving wave equations with potentials. In this work we study the bound states of matter particles with various types of interactions, including electromagnetic and gravitational interactions. Our work has many analogies with the work started by Alday and Maldacena, who computed scattering amplitudes of gluons at strong coupling with semiclassical quantum mechanics of strings in anti de-Sitter spacetime. We hope that in the future we can apply our

  8. Piloted simulator study of allowable time delay in pitch flight control system of a transport airplane with negative static stability

    NASA Technical Reports Server (NTRS)

    Grantham, William D.; Smith, Paul M.; Person, Lee H., Jr.; Meyer, Robert T.; Tingas, Stephen A.

    1987-01-01

    A piloted simulation study was conducted to determine the permissible time delay in the flight control system of a 10-percent statically unstable transport airplane during cruise flight conditions. The math model used for the simulation was a derivative Lockheed L-1011 wide-body jet transport. Data were collected and analyzed from a total of 137 cruising flights in both calm- and turbulent-air conditions. Results of this piloted simulation study verify previous findings that show present military specifications for allowable control-system time delay may be too stringent when applied to transport-size airplanes. Also, the degree of handling-qualities degradation due to time delay is shown to be strongly dependent on the source of the time delay in an advanced flight control system. Maximum allowable time delay for each source of time delay in the control system, in addition to a less stringent overall maximum level of time delay, should be considered for large aircraft. Preliminary results also suggest that adverse effects of control-system time delay may be at least partially offset by variations in control gearing. It is recommended that the data base include different airplane baselines, control systems, and piloting tasks with many pilots participating, so that a reasonable set of limits for control-system time delay can be established to replace the military specification limits currently being used.

  9. Delayed feedback control of cavity solitons in a broad area vertical cavity surface emitting laser with saturable absorbtion

    NASA Astrophysics Data System (ADS)

    Gurevich, S. V.; Schelte, C.; Tlidi, M.; Panajotov, K.

    2016-04-01

    We are interested in spatio-temporal dynamics of cavity solitons (CSs) in a transverse section of a broad area vertical cavity surface emitting laser (VCSEL) with saturable absorbtion subjected to time-delayed optical feedback. In the absence of delayed feedback, a single branch of localized solutions appears in the parameter space. However, in the presence of the delayed feedback, multistability of CS solutions emerges; The branches of CSs fill the surface of the "solution tube" in the parameter space, which is filled densely with increasing delay time. Further, our study reveals that the multistability of stationary solutions is caused by a delayed-induced phase bifurcation of CSs. Furthermore, it was shown that stability properties of CSs strongly depend on the delayed feedback parameters. In particular, the thresholds of the drift and phase bifurcations as well as corresponding bifurcation diagrams are obtained by a combination of analytical and numerical continuation methods. It turns out that both thresholds tend to zero in the limit of large delay times. In addition, we demonstrate that the presence of the delayed optical feedback can induce Andronov-Hopf bifurcation and a period doubling route to chaos. Moreover, a coupling between this bifurcation scenario with aforementioned delay-induced multistability leads to a complex spatio-temporal behavior of the system in question. The results of analytical bifurcation analysis are in agreement with those obtained by direct numerical integration of the model equation.

  10. Rrsm: The European Rapid Raw Strong-Motion Database

    NASA Astrophysics Data System (ADS)

    Cauzzi, C.; Clinton, J. F.; Sleeman, R.; Domingo Ballesta, J.; Kaestli, P.; Galanis, O.

    2014-12-01

    We introduce the European Rapid Raw Strong-Motion database (RRSM), a Europe-wide system that provides parameterised strong motion information, as well as access to waveform data, within minutes of the occurrence of strong earthquakes. The RRSM significantly differs from traditional earthquake strong motion dissemination in Europe, which has focused on providing reviewed, processed strong motion parameters, typically with significant delays. As the RRSM provides rapid open access to raw waveform data and metadata and does not rely on external manual waveform processing, RRSM information is tailored to seismologists and strong-motion data analysts, earthquake and geotechnical engineers, international earthquake response agencies and the educated general public. Access to the RRSM database is via a portal at http://www.orfeus-eu.org/rrsm/ that allows users to query earthquake information, peak ground motion parameters and amplitudes of spectral response; and to select and download earthquake waveforms. All information is available within minutes of any earthquake with magnitude ≥ 3.5 occurring in the Euro-Mediterranean region. Waveform processing and database population are performed using the waveform processing module scwfparam, which is integrated in SeisComP3 (SC3; http://www.seiscomp3.org/). Earthquake information is provided by the EMSC (http://www.emsc-csem.org/) and all the seismic waveform data is accessed at the European Integrated waveform Data Archive (EIDA) at ORFEUS (http://www.orfeus-eu.org/index.html), where all on-scale data is used in the fully automated processing. As the EIDA community is continually growing, the already significant number of strong motion stations is also increasing and the importance of this product is expected to also increase. Real-time RRSM processing started in June 2014, while past events have been processed in order to provide a complete database back to 2005.

  11. Tropospheric Delay Raytracing Applied in VLBI Analysis

    NASA Astrophysics Data System (ADS)

    MacMillan, D. S.; Eriksson, D.; Gipson, J. M.

    2013-12-01

    Tropospheric delay modeling error continues to be one of the largest sources of error in VLBI analysis. For standard operational solutions, we use the VMF1 elevation-dependent mapping functions derived from ECMWF data. These mapping functions assume that tropospheric delay at a site is azimuthally symmetric. As this assumption does not reflect reality, we have determined the raytrace delay along the signal path through the troposphere for each VLBI quasar observation. We determined the troposphere refractivity fields from the pressure, temperature, specific humidity and geopotential height fields of the NASA GSFC GEOS-5 numerical weather model. We discuss results from analysis of the CONT11 R&D and the weekly operational R1+R4 experiment sessions. When applied in VLBI analysis, baseline length repeatabilities were better for 66-72% of baselines with raytraced delays than with VMF1 mapping functions. Vertical repeatabilities were better for 65% of sites.

  12. SBASI: Actuated pyrotechnic time delay initiator

    NASA Technical Reports Server (NTRS)

    Salter, S. J.; Lundberg, R. E.; Mcdougal, G. L.

    1975-01-01

    A precision pyrotechnic time delay initiator for missile staging was developed and tested. Incorporated in the assembly is a single bridgewire Apollo standard initiator (SBASI) for initiation, a through-bulkhead-initiator to provide isolation of the SBASI output from the delay, the pyrotechnic delay, and an output charge. An attempt was made to control both primary and secondary variables affecting functional performance of the delay initiator. Design and functional limit exploration was performed to establish tolerance levels on manufacturing and assembling operations. The test results demonstrate a 2% coefficient of variation at any one temperature and an overall 2.7% coefficient of variation throughout the temperature range of 30 to 120 F. Tests were conducted at simulated operational altitude from sea level to 200,000 feet.

  13. Resonance Effects in Photoemission Time Delays.

    PubMed

    Sabbar, M; Heuser, S; Boge, R; Lucchini, M; Carette, T; Lindroth, E; Gallmann, L; Cirelli, C; Keller, U

    2015-09-25

    We present measurements of single-photon ionization time delays between the outermost valence electrons of argon and neon using a coincidence detection technique that allows for the simultaneous measurement of both species under identical conditions. The analysis of the measured traces reveals energy-dependent time delays of a few tens of attoseconds with high energy resolution. In contrast to photoelectrons ejected through tunneling, single-photon ionization can be well described in the framework of Wigner time delays. Accordingly, the overall trend of our data is reproduced by recent Wigner time delay calculations. However, besides the general trend we observe resonance features occurring at specific photon energies. These features have been qualitatively reproduced and identified by a calculation using the multiconfigurational Hartree-Fock method, including the influence of doubly excited states and ionization thresholds. PMID:26451550

  14. Maintained generalization of delay-specific remembering.

    PubMed

    White, K Geoffrey; Sargisson, Rebecca J

    2011-07-01

    According to the discrimination hypothesis (White, 2002), remembering is a delay-specific discrimination made at the time of retrieval. In the present experiment the delay-specific nature of the discrimination was made explicit by making correct choices in a delayed matching-to-sample task performed by pigeons conditional on whether the retention interval was short or long. Retention interval was varied over several durations in a maintained generalization test without reinforcement for correct matching responses. Opposing gradients demonstrated generalization of delay-specific remembering, consistent with the view that the temporal dimension of the retention interval can be treated in the same way as non-temporal dimensions of the sample stimulus. PMID:21704683

  15. The evolution of seasonal delayed implantation.

    PubMed

    Sandell, M

    1990-03-01

    Seasonal delayed implantation has been described in 47 mammalian species in ten families, and has evolved independently at least 17 times. After reviewing earlier explanations for the phenomenon I present a hypothesis to explain the evolution of seasonal delay. I have assumed that females can increase their fitness by choosing their mates. Consequently, mating should take place during that time of year when the possibilities for female choice or male competition are greatest. Time of birth is determined by ecological factors promoting survival of the young, thereby setting certain constraints on the scheduling of the mating season. In certain situations, however, the possibilities for female choice or male competition can be increased by mating earlier; delay will increase female fitness, and will thereby evolve. The hypothesis has been applied to all cases of seasonal delayed implantation. PMID:2186428

  16. 48 CFR 1352.271-77 - Delays.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... in 48 CFR 1371.108, insert the following clause: Delays (APR 2010) When, during the performance of... actions of the Government respecting stoppage of work to permit shifting the vessel, stoppage of hot...

  17. 48 CFR 1352.271-77 - Delays.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... in 48 CFR 1371.108, insert the following clause: Delays (APR 2010) When, during the performance of... actions of the Government respecting stoppage of work to permit shifting the vessel, stoppage of hot...

  18. The SAS-3 delayed command system

    NASA Technical Reports Server (NTRS)

    Hoffman, E. J.

    1975-01-01

    To meet the requirements arising from the increased complexity of the power, attitude control and telemetry systems, a full redundant high-performance control section with delayed command capability was designed for the Small Astronomy Satellite-3 (SAS-3). The relay command system of SAS-3 is characterized by 56 bystate relay commands, with capability for handling up to 64 commands in future versions. The 'short' data command service of SAS-1 and SAS-2 consisting of shifting 24-bit words to two users was expanded to five users and augmented with a 'long load' data command service (up to 4080 bits) used to program the telemetry system and the delayed command subsystem. The inclusion of a delayed command service ensures a program of up to 30 relay or short data commands to be loaded for execution at designated times. The design and system operation of the SAS-3 command section are analyzed, with special attention given to the delayed command subsystem.

  19. How Can Atherosclerosis Be Prevented or Delayed?

    MedlinePlus

    ... page from the NHLBI on Twitter. How Can Atherosclerosis Be Prevented or Delayed? Taking action to control ... Rate This Content: NEXT >> Featured Video What is atherosclerosis? 05/22/2014 Describes how the build-up ...

  20. Dry Mouth? Don't Delay Treatment

    MedlinePlus

    ... For Consumers Home For Consumers Consumer Updates Dry Mouth? Don't Delay Treatment Share Tweet Linkedin Pin ... saliva, cavities may occur. back to top Dry Mouth Treatments Your doctor or dentist may recommend oral ...

  1. Speed and delay on signalized arterials

    SciTech Connect

    Levinson, D.M.

    1998-05-01

    This paper presents a model to predict the influence of traffic flow on the running speed of signalized arterials in Montgomery County, Maryland, while controlling for link length, the number of lanes, and route type. The model separates the changes to link running speed due to same-direction traffic and intersection approach delay from cross-traffic. It is found that flow has a small impact on link speed, each 1,000 v/l/h reduces speed by 4--8 k/h. Longer links have higher speeds, indicating that they more closely approximate free-flow conditions. Measures of intersection and link travel times are also compared. Although link running times exceed intersection stopped delay in general, total intersection delay (stopped and approach) exceeds the delay caused by same-direction traffic. This information can inform investment decision makers about roadway and intersection improvements.

  2. Delayed onset of the 2002 Indian monsoon

    NASA Astrophysics Data System (ADS)

    Flatau, M. K.; Flatau, P. J.; Schmidt, J.; Kiladis, G. N.

    2003-07-01

    We show that there is a set of dynamical predictors, which facilitate forecasting of a delayed monsoon onset. The main dynamical contributor is the early May propagation of the ``bogus onset Intraseasonal Oscillation'' which triggers a set of events precluding the climatological monsoon onset. We analyze in detail the 2002 monsoon onset and show that it followed a pattern described in our previous study. We notice that the 2003 monsoon onset followed very similar pattern and was delayed.

  3. Delayed stoma formation in Fournier's gangrene.

    PubMed

    Bronder, C S; Cowey, A; Hill, J

    2004-11-01

    Fournier's gangrene is traditionally treated with prompt surgical debridement and in many cases a diverting colostomy is also fashioned during the same procedure. We present four cases where stoma formation was delayed until the second look procedure. The physiological states at the time of either procedure were compared using POSSUM. The results showed an improvement in the physiological condition in all patients at the time of the second operation, suggesting that a delay can potentially improve prognosis in such cases. PMID:15521946

  4. Strong Winds over the Keel

    NASA Astrophysics Data System (ADS)

    2009-02-01

    The latest ESO image reveals amazing detail in the intricate structures of one of the largest and brightest nebulae in the sky, the Carina Nebula (NGC 3372), where strong winds and powerful radiation from an armada of massive stars are creating havoc in the large cloud of dust and gas from which the stars were born. ESO PR Photo 05a/09 The Carina Nebula ESO PR Video 05a/09 Pan over the Carina Nebula ESO PR Video 05b/09 Carina Nebula Zoom-in The large and beautiful image displays the full variety of this impressive skyscape, spattered with clusters of young stars, large nebulae of dust and gas, dust pillars, globules, and adorned by one of the Universe's most impressive binary stars. It was produced by combining exposures through six different filters from the Wide Field Imager (WFI), attached to the 2.2 m ESO/MPG telescope at ESO's La Silla Observatory, in Chile. The Carina Nebula is located about 7500 light-years away in the constellation of the same name (Carina; the Keel). Spanning about 100 light-years, it is four times larger than the famous Orion Nebula and far brighter. It is an intensive star-forming region with dark lanes of cool dust splitting up the glowing nebula gas that surrounds its many clusters of stars. The glow of the Carina Nebula comes mainly from hot hydrogen basking in the strong radiation of monster baby stars. The interaction between the hydrogen and the ultraviolet light results in its characteristic red and purple colour. The immense nebula contains over a dozen stars with at least 50 to 100 times the mass of our Sun. Such stars have a very short lifespan, a few million years at most, the blink of an eye compared with the Sun's expected lifetime of ten billion years. One of the Universe's most impressive stars, Eta Carinae, is found in the nebula. It is one of the most massive stars in our Milky Way, over 100 times the mass of the Sun and about four million times brighter, making it the most luminous star known. Eta Carinae is highly

  5. Speech and language delay in children.

    PubMed

    McLaughlin, Maura R

    2011-05-15

    Speech and language delay in children is associated with increased difficulty with reading, writing, attention, and socialization. Although physicians should be alert to parental concerns and to whether children are meeting expected developmental milestones, there currently is insufficient evidence to recommend for or against routine use of formal screening instruments in primary care to detect speech and language delay. In children not meeting the expected milestones for speech and language, a comprehensive developmental evaluation is essential, because atypical language development can be a secondary characteristic of other physical and developmental problems that may first manifest as language problems. Types of primary speech and language delay include developmental speech and language delay, expressive language disorder, and receptive language disorder. Secondary speech and language delays are attributable to another condition such as hearing loss, intellectual disability, autism spectrum disorder, physical speech problems, or selective mutism. When speech and language delay is suspected, the primary care physician should discuss this concern with the parents and recommend referral to a speech-language pathologist and an audiologist. There is good evidence that speech-language therapy is helpful, particularly for children with expressive language disorder. PMID:21568252

  6. Ladder-structured photonic variable delay device

    NASA Technical Reports Server (NTRS)

    Yao, X. Steve (Inventor)

    1998-01-01

    An ladder-structured variable delay device for providing variable true time delay to multiple optical beams simultaneously. The device comprises multiple basic units stacked on top of each other resembling a ladder. Each basic unit comprises a polarization sensitive corner reflector formed by two polarization beamsplitters and a polarization rotator array placed parallel to the hypotenuse of the corner reflector. Controlling an array element of the polarization rotator array causes an optical beam passing through the array element to either go up to a basic unit above it or reflect back towards output. The beams going higher on the ladder experience longer optical path delay. Finally, the ladder-structured variable device can be cascaded with another multi-channel delay device to form a new device which combines the advantages of the two individual devices. This programmable optic device has the properties of high packing density, low loss, easy fabrication, and virtually infinite bandwidth. In addition, the delay is reversible so that the same delay device can be used for both antenna transmitting and receiving.

  7. Estimating ionospheric delay using kriging: 1. Methodology

    NASA Astrophysics Data System (ADS)

    Sparks, Lawrence; Blanch, Juan; Pandya, Nitin

    2011-12-01

    The Wide Area Augmentation System (WAAS) is an augmentation of the Global Positioning System (GPS) that provides safe and reliable use of GPS signals for airline navigation over much of North America. Ever since WAAS was first commissioned in July of 2003, the vertical delay estimate at each node in the WAAS ionospheric grid has been determined from a planar fit of slant delay measurements, projected to vertical using an obliquity factor specified by the standard thin shell model of the ionosphere. In a future WAAS upgrade (WAAS Follow-On Release 3), however, the vertical delay will be estimated by an established, geo-statistical technique known as kriging. When compared to the planar fit model, the kriging model is generally found to match better the observed random structure of the vertical delay. This paper presents the kriging methodology to be used to estimate the vertical delay and its uncertainty at each ionospheric grid point. In addition, it provides examples of the improvement in delay accuracy achieved. Under disturbed conditions, the implementation of kriging reduces the magnitude of the root mean square fit residual by up to 15%.

  8. Strongly correlated perovskite fuel cells.

    PubMed

    Zhou, You; Guan, Xiaofei; Zhou, Hua; Ramadoss, Koushik; Adam, Suhare; Liu, Huajun; Lee, Sungsik; Shi, Jian; Tsuchiya, Masaru; Fong, Dillon D; Ramanathan, Shriram

    2016-06-01

    Fuel cells convert chemical energy directly into electrical energy with high efficiencies and environmental benefits, as compared with traditional heat engines. Yttria-stabilized zirconia is perhaps the material with the most potential as an electrolyte in solid oxide fuel cells (SOFCs), owing to its stability and near-unity ionic transference number. Although there exist materials with superior ionic conductivity, they are often limited by their ability to suppress electronic leakage when exposed to the reducing environment at the fuel interface. Such electronic leakage reduces fuel cell power output and the associated chemo-mechanical stresses can also lead to catastrophic fracture of electrolyte membranes. Here we depart from traditional electrolyte design that relies on cation substitution to sustain ionic conduction. Instead, we use a perovskite nickelate as an electrolyte with high initial ionic and electronic conductivity. Since many such oxides are also correlated electron systems, we can suppress the electronic conduction through a filling-controlled Mott transition induced by spontaneous hydrogen incorporation. Using such a nickelate as the electrolyte in free-standing membrane geometry, we demonstrate a low-temperature micro-fabricated SOFC with high performance. The ionic conductivity of the nickelate perovskite is comparable to the best-performing solid electrolytes in the same temperature range, with a very low activation energy. The results present a design strategy for high-performance materials exhibiting emergent properties arising from strong electron correlations. PMID:27279218

  9. Strongly correlated perovskite fuel cells

    NASA Astrophysics Data System (ADS)

    Zhou, You; Guan, Xiaofei; Zhou, Hua; Ramadoss, Koushik; Adam, Suhare; Liu, Huajun; Lee, Sungsik; Shi, Jian; Tsuchiya, Masaru; Fong, Dillon D.; Ramanathan, Shriram

    2016-06-01

    Fuel cells convert chemical energy directly into electrical energy with high efficiencies and environmental benefits, as compared with traditional heat engines. Yttria-stabilized zirconia is perhaps the material with the most potential as an electrolyte in solid oxide fuel cells (SOFCs), owing to its stability and near-unity ionic transference number. Although there exist materials with superior ionic conductivity, they are often limited by their ability to suppress electronic leakage when exposed to the reducing environment at the fuel interface. Such electronic leakage reduces fuel cell power output and the associated chemo-mechanical stresses can also lead to catastrophic fracture of electrolyte membranes. Here we depart from traditional electrolyte design that relies on cation substitution to sustain ionic conduction. Instead, we use a perovskite nickelate as an electrolyte with high initial ionic and electronic conductivity. Since many such oxides are also correlated electron systems, we can suppress the electronic conduction through a filling-controlled Mott transition induced by spontaneous hydrogen incorporation. Using such a nickelate as the electrolyte in free-standing membrane geometry, we demonstrate a low-temperature micro-fabricated SOFC with high performance. The ionic conductivity of the nickelate perovskite is comparable to the best-performing solid electrolytes in the same temperature range, with a very low activation energy. The results present a design strategy for high-performance materials exhibiting emergent properties arising from strong electron correlations.

  10. Strong Expectations Cancel Locality Effects: Evidence from Hindi

    PubMed Central

    Husain, Samar; Vasishth, Shravan; Srinivasan, Narayanan

    2014-01-01

    Expectation-driven facilitation (Hale, 2001; Levy, 2008) and locality-driven retrieval difficulty (Gibson, 1998, 2000; Lewis & Vasishth, 2005) are widely recognized to be two critical factors in incremental sentence processing; there is accumulating evidence that both can influence processing difficulty. However, it is unclear whether and how expectations and memory interact. We first confirm a key prediction of the expectation account: a Hindi self-paced reading study shows that when an expectation for an upcoming part of speech is dashed, building a rarer structure consumes more processing time than building a less rare structure. This is a strong validation of the expectation-based account. In a second study, we show that when expectation is strong, i.e., when a particular verb is predicted, strong facilitation effects are seen when the appearance of the verb is delayed; however, when expectation is weak, i.e., when only the part of speech “verb” is predicted but a particular verb is not predicted, the facilitation disappears and a tendency towards a locality effect is seen. The interaction seen between expectation strength and distance shows that strong expectations cancel locality effects, and that weak expectations allow locality effects to emerge. PMID:25010700

  11. Tropospheric delays from GNSS for application in coastal altimetry

    NASA Astrophysics Data System (ADS)

    Fernandes, M. Joana; Pires, Nelson; Lázaro, Clara; Nunes, Alexandra L.

    2013-04-01

    of the hydrostatic component of the tropospheric delay with an accuracy of 1 to 3 mm at global scale, provided an adequate model for the height dependence of atmospheric pressure is adopted. In comparison, for VMF1 grids provided at 2.5° spacing, although the overall accuracy of ZHD estimation is 2-4 mm in most sites, in regions with high variability and strong seasonal signal in the surface pressure, VMF1 can reveal errors with a clear annual pattern and epochs for which the error exceeds the centimetre level. When used to estimate the wet component of the tropospheric delay (zenith wet delay, ZWD) for coastal altimetry, these errors can translate into errors of similar magnitude in sea level studies.

  12. Apparatus and Method for Compensating for Process, Voltage, and Temperature Variation of the Time Delay of a Digital Delay Line

    NASA Technical Reports Server (NTRS)

    Seefeldt, James (Inventor); Feng, Xiaoxin (Inventor); Roper, Weston (Inventor)

    2013-01-01

    A process, voltage, and temperature (PVT) compensation circuit and a method of continuously generating a delay measure are provided. The compensation circuit includes two delay lines, each delay line providing a delay output. The two delay lines may each include a number of delay elements, which in turn may include one or more current-starved inverters. The number of delay lines may differ between the two delay lines. The delay outputs are provided to a combining circuit that determines an offset pulse based on the two delay outputs and then averages the voltage of the offset pulse to determine a delay measure. The delay measure may be one or more currents or voltages indicating an amount of PVT compensation to apply to input or output signals of an application circuit, such as a memory-bus driver, dynamic random access memory (DRAM), a synchronous DRAM, a processor or other clocked circuit.

  13. Developmental profiles of preschool children with delayed language development

    PubMed Central

    Eun, Jeong Ji; Lee, Hyung Jik

    2014-01-01

    Purpose This study examines changes in developmental profiles of children with language delay over time and the clinical significance of assessment conducted at age 2-3 years. Methods We retrospectively reviewed the medical records of 70 children (62 male, 8 female), who had visited the hospital because of delayed language development at 2-3 years, and were reassessed at ages 5-6. Language and cognitive abilities were assessed using multiple scales at the initial and follow-up visits. Results At the initial test, 62 of the 70 children had mental development index (MDI) below 70 of Bayley Scales of Infant Development Test II. Of the 62 children in the follow-up assessment, 30 children (48.4%) remained within the same cognitive range (full-scale intelligence quotient, FSIQ<70 of Wechsler preschool and primary scale of intelligence), 12 had borderline intellectual functioning (FSIQ, 70-85), 6 improved to average intellectual functioning (FSIQ>85), and 5 had specific language impairment, 9 had autism spectrum disorders. At the initial test, 38 of the 70 children had cognitive developmental quotients (C-DQ) below 70. Of the 38 children in the follow-up assessment, 23 children (60.5%) remained within the same cognitive range (FSIQ<70). The correlation coefficient for MDI and FSIQ was 0.530 (P<0.0001) and that for C-DQ and FSIQ was 0.727 (P<0.0001). There was a strong correlation between C-DQ and FSIQ, and a moderate correlation between MDI and FSIQ. Conclusion Low MDI scores reflect a specific delay in cognitive abilities, communication skills, or both. The C-DQ, receptive language development quotient, and social maturity quotient also help to distinguish between children with isolated language delay and children with cooccurring cognitive impairment. Moreover, changes in the developmental profile during preschool years are not unusual in children with language delay. Follow-up reassessments prior to the start of school are required for a more accurate diagnosis and

  14. Advanced X-Ray Astrophysics Facility Delivery Delayed

    NASA Astrophysics Data System (ADS)

    1997-12-01

    TRW Space and Electronics Group, Redondo Beach, CA, has notified NASA that it will be unable to deliver the Advanced X-ray Astrophysics Facility (AXAF) to NASA's Kennedy Space Center, FL, on June 1, 1998, as required by contract, because it has experienced delays in assembly and testing of the facility. TRW is NASA's prime contractor for the observatory. NASA and contractor officials met at NASA Headquarters in Washington, DC, this week to discuss the issue. While no new delivery date was agreed upon, the agency has directed TRW to develop a plan of action that would show how the contractor can minimize impact to the June 1 delivery. Although a delay in delivery could delay the launch, currently scheduled for August 1998 aboard Space Shuttle Columbia's STS-93 mission, and could result in additional program costs, the exact impact is not yet known. "The delay in delivery of the observatory is unfortunate," said Fred Wojtalik, NASA Marshall Space Flight Center observatory projects office manager in Huntsville, AL. "However, our first priority is to launch a world-class observatory which has been thoroughly tested and meets all requirements. We will work closely with TRW to ensure that happens." The delay is primarily due to TRW's difficulty in configuring and programming its Integrated Spacecraft Automated Test System to test the observatory before it is delivered to NASA. The Advanced X-ray Astrophysics Facility is expected to play a vital role in answering fundamental questions about the universe, including its age and size, and will probe the nature and amounts of so-called "dark matter," providing unique insight into one of nature's great puzzles. The observatory also will allow scientists to see and measure the details of hot gas clouds in clusters of galaxies; observe X-rays generated when stars are torn apart by the incredibly strong gravity around massive black holes in the centers of galaxies; and provide images that will help understand how exploding stars

  15. RATES AND DELAY TIMES OF TYPE Ia SUPERNOVAE

    SciTech Connect

    Ruiter, Ashley J.; Belczynski, Krzysztof; Fryer, Chris E-mail: kbelczyn@nmsu.edu

    2009-07-10

    We analyze the evolution of binary stars to calculate synthetic rates and delay times of the most promising Type Ia Supernovae (SNe Ia) progenitors. We present and discuss evolutionary scenarios in which a white dwarf (WD) reaches the Chandrasekhar mass and potentially explodes in a SNe Ia. We consider Double Degenerate (DDS; merger of two WDs), Single Degenerate (SDS; WD accreting from H-rich companion), and AM Canum Venaticorum (AM CVn; WD accreting from He-rich companion) scenarios. The results are presented for two different star formation histories: burst (elliptical-like galaxies) and continuous (spiral-like galaxies). It is found that delay times for the DDS in our standard model (with common envelope efficiency {alpha}{sub CE} = 1) follow a power-law distribution. For the SDS we note a wide range of delay times, while AM CVn progenitors produce a short burst of SNe Ia at early times. The DDS median delay time falls between {approx}0.5 and 1 Gyr; the SDS between {approx}2 and 3 Gyr; and the AM CVn between {approx}0.8 and 0.6 Gyr depending on the assumed {alpha}{sub CE}. For a Milky-Way-like (MW-like) galaxy, we estimate the rates of SNe Ia arising from different progenitors as: {approx}10{sup -4} yr{sup -1} for the SDS and AM CVn, and {approx}10{sup -3} yr{sup -1} for the DDS. We point out that only the rates for two merging carbon-oxygen WDs, the only systems found in the DDS, are consistent with the observed rates for typical MW-like spirals. We also note that DDS progenitors are the dominant population in elliptical galaxies. The fact that the delay time distribution for the DDS follows a power law implies more SNe Ia (per unit mass) in young rather than in aged populations. Our results do not exclude other scenarios, but strongly indicate that the DDS is the dominant channel generating SNe Ia in spiral galaxies, at least in the framework of our adopted evolutionary models. Since it is believed that WD mergers cannot produce a thermonuclear explosion

  16. Binaural interaction in low-frequency neurons in inferior colliculus of the cat. I. Effects of long interaural delays, intensity, and repetition rate on interaural delay function.

    PubMed

    Kuwada, S; Yin, T C

    1983-10-01

    form of time-intensity trading. A few cells demonstrated orderly changes in the interaural delay curve as the repetition rate of the stimulus was varied. Some of these changes are consonant with an inhibitory effect that occurs at stimulus offset. The responses of the neurons show a strong bias for stimuli that would originate from he contralateral sound field; 77% of the responses display mean interaural phase angles that are less than 0.5 of a cycle, which are delays to the ipsilateral tone.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:6631473

  17. Promoting Strong Written Communication Skills

    NASA Astrophysics Data System (ADS)

    Narayanan, M.

    2015-12-01

    The reason that an improvement in the quality of technical writing is still needed in the classroom is due to the fact that universities are facing challenging problems not only on the technological front but also on the socio-economic front. The universities are actively responding to the changes that are taking place in the global consumer marketplace. Obviously, there are numerous benefits of promoting strong written communication skills. They can be summarized into the following six categories. First, and perhaps the most important: The University achieves learner satisfaction. The learner has documented verbally, that the necessary knowledge has been successfully acquired. This results in learner loyalty that in turn will attract more qualified learners.Second, quality communication lowers the cost per pupil, consequently resulting in increased productivity backed by a stronger economic structure and forecast. Third, quality communications help to improve the cash flow and cash reserves of the university. Fourth, having high quality communication enables the university to justify the need for high costs of tuition and fees. Fifth, better quality in written communication skills result in attracting top-quality learners. This will lead to happier and satisfied learners, not to mention greater prosperity for the university as a whole. Sixth, quality written communication skills result in reduced complaints, thus meaning fewer hours spent on answering or correcting the situation. The University faculty and staff are thus able to devote more time on scholarly activities, meaningful research and productive community service. References Boyer, Ernest L. (1990). Scholarship reconsidered: Priorities of the Professorate.Princeton, NJ: Carnegie Foundation for the Advancement of Teaching. Hawkins, P., & Winter, J. (1997). Mastering change: Learning the lessons of the enterprise.London: Department for Education and Employment. Buzzel, Robert D., and Bradley T. Gale. (1987

  18. Preferences for fixed and variable food sources: variability in amount and delay.

    PubMed Central

    Bateson, M; Kacelnik, A

    1995-01-01

    Much research has focused on the effects of environmental variability on foraging decisions. However, the general pattern of preference for variability in delay to reward and aversion to variability in amount of reward remains unexplained a either a mechanistic or a functional level. Starlings' preferences between a fixed and a variable option were studied in two treatments, A and D. The fixed option was the same in both treatments (20-s fixed-interval delay, five units food). In Treatment A the variable option gave two equiprobable amounts of food (20-s delay, three or seven units) and in D it gave two equiprobable delays to food (2.5-s or 60.5-s delays, five units). In both treatments the programmed ratio [amount/(intertrial interval+latency+delay)] in the fixed option equaled the arithmetic mean of the two possible ratios in the variable option (ITI = 40 s, latency = 1 s). The variable option was strongly preferred in Treatment D and was weakly avoided in Treatment A. These results are discussed in the light of two theoretical models, a form of constrained rate maximization and a version of scalar expectancy theory. The latter accommodates more of the data and is based on independently verifiable assumptions, including Weber's law. PMID:7751835

  19. Delay Differential Analysis of Time Series

    PubMed Central

    Lainscsek, Claudia; Sejnowski, Terrence J.

    2015-01-01

    Nonlinear dynamical system analysis based on embedding theory has been used for modeling and prediction, but it also has applications to signal detection and classification of time series. An embedding creates a multidimensional geometrical object from a single time series. Traditionally either delay or derivative embeddings have been used. The delay embedding is composed of delayed versions of the signal, and the derivative embedding is composed of successive derivatives of the signal. The delay embedding has been extended to nonuniform embeddings to take multiple timescales into account. Both embeddings provide information on the underlying dynamical system without having direct access to all the system variables. Delay differential analysis is based on functional embeddings, a combination of the derivative embedding with nonuniform delay embeddings. Small delay differential equation (DDE) models that best represent relevant dynamic features of time series data are selected from a pool of candidate models for detection or classification. We show that the properties of DDEs support spectral analysis in the time domain where nonlinear correlation functions are used to detect frequencies, frequency and phase couplings, and bispectra. These can be efficiently computed with short time windows and are robust to noise. For frequency analysis, this framework is a multivariate extension of discrete Fourier transform (DFT), and for higher-order spectra, it is a linear and multivariate alternative to multidimensional fast Fourier transform of multidimensional correlations. This method can be applied to short or sparse time series and can be extended to cross-trial and cross-channel spectra if multiple short data segments of the same experiment are available. Together, this time-domain toolbox provides higher temporal resolution, increased frequency and phase coupling information, and it allows an easy and straightforward implementation of higher-order spectra across time

  20. Buoyancy-induced time delays in Babcock-Leighton flux-transport dynamo models

    NASA Astrophysics Data System (ADS)

    Jouve, L.; Proctor, M. R. E.; Lesur, G.

    2010-09-01

    Context. The Sun is a magnetic star whose cyclic activity is thought to be linked to internal dynamo mechanisms. A combination of numerical modelling with various levels of complexity is an efficient and accurate tool to investigate such intricate dynamical processes. Aims: We investigate the role of the magnetic buoyancy process in 2D Babcock-Leighton dynamo models, by modelling more accurately the surface source term for poloidal field. Methods: To do so, we reintroduce in mean-field models the results of full 3D MHD calculations of the non-linear evolution of a rising flux tube in a convective shell. More specifically, the Babcock-Leighton source term is modified to take into account the delay introduced by the rise time of the toroidal structures from the base of the convection zone to the solar surface. Results: We find that the time delays introduced in the equations produce large temporal modulation of the cycle amplitude even when strong and thus rapidly rising flux tubes are considered. Aperiodic modulations of the solar cycle appear after a sequence of period doubling bifurcations typical of non-linear systems. The strong effects introduced even by small delays is found to be due to the dependence of the delays on the magnetic field strength at the base of the convection zone, the modulation being much less when time delays remain constant. We do not find any significant influence on the cycle period except when the delays are made artificially strong. Conclusions: A possible new origin of the solar cycle variability is here revealed. This modulated activity and the resulting butterfly diagram are then more compatible with observations than what the standard Babcock-Leighton model produces.

  1. Presentation delay in breast cancer patients and its association with sociodemographic factors in North Pakistan

    PubMed Central

    Hanif, Sheharyar; Iqbal, Sundas; Shahzad, Muhammad Faheem; Shafique, Sehrish; Khan, Muhammad Taha

    2015-01-01

    Background There is strong evidence that delayed diagnosis of breast cancer is associated with poor survival. The objectives were to determine the frequency of breast cancer patients with delayed presentation, the reasons of delay and its association with different socio-demographic variables in our settings. Methods We interviewed 315 histologically confirmed breast cancer patients. Delay was defined as more than 3 months from appearance of symptoms to the consultation from doctor. Questions were asked from each patient which could reflect their understanding about the disease and which could be the likely reasons for their delayed presentation. Results A total of 39.01% (n=123) of patients presented late and out of those, 40.7% wasted time using alternative medicines; 25.2% were not having enough resources; 17.1% presented late due to painless lump; 10.6% felt shyness and 6.5% presented late due to other reasons. Higher age, negative family history, <8 school years of education and low to middle socio-economic status were significantly associated with delayed presentation (P<0.05). Education and socioeconomic status were two independent variables related to the delayed presentation after adjustment for others [odds ratios (OR) of 2.26, 2.29 and 95% confidence intervals (CI) was 1.25-4.10, 1.06-4.94 respectively]. Conclusions Significant percentage of women with breast cancer in North Pakistan is experiencing presentation delay due to their misconceptions about the disease. Coordinated efforts with public health department are needed to educate the focused groups and mitigating the barriers identified in the study. Long term impact will be reduced overall burden of the disease in the region. PMID:26157325

  2. Test structures for propagation delay measurements on high-speed integrated circuits

    NASA Technical Reports Server (NTRS)

    Long, S. I.

    1984-01-01

    The accuracy of high-speed wafer-level measurements on digital IC's is limited by the probe interface. This limitation strongly encourages the use of built-in on-chip test hardware to reduce the number of critical off-chip high-speed interfaces. A novel synchronous propagation delay test structure is described which will provide accurate parametric data under typical automatic test conditions. Built-in test features added to complex combinational circuits are shown which are useful for delay measurement and which reduce the total number of high-speed I/O connections while still providing acceptable fault coverage in many cases.

  3. [Progress in the studies of semen delayed liquefaction from chronic prostatitis].

    PubMed

    Zhang, Yi-fei; Liang, Chao-zhao

    2007-01-01

    Chronic prostatitis (CP) is a common disease among adult men. It can result in male infertility mainly by alternating the semen quality, volume, pH, component, viscosity and liquefaction. There seems to be a strong association between CP and semen delayed liquefaction. Researches on the mechanism of semen delayed liquefaction resulting from CP mainly focus on the proteolytic ferment, plasminogen activator, prostate acid phosphatase, tissue factor, lack of zinc, and pH. This article briefly reviews the progress in these aspects. PMID:17302037

  4. Observation of delayed electron emission in a two-phase liquid xenon detector

    NASA Astrophysics Data System (ADS)

    Akimov, D. Yu.; Belov, V. A.; Bolozdynya, A. I.; Burenkov, A. A.; Efremenko, Yu. V.; Etenko, A. V.; Kaplin, V. A.; Karelin, A. K.; Khromov, A. V.; Kirsanov, M. A.; Klimanov, S. G.; Kobyakin, A. S.; Konovalov, A. M.; Kovalenko, A. G.; Kuchenkov, A. V.; Kumpan, A. V.; Melikyan, Yu. A.; Nikolaev, R. I.; Rudik, D. G.; Simakov, G. E.; Sosnovtsev, V. V.; Stekhanov, V. N.

    2016-03-01

    Results of the experimental study of electron emission from liquid xenon via electroluminescence of the gas phase are presented. We report on observation of a peculiar kind of delayed electroluminescent signal following initial electroluminescence caused by ionizing particles. We also present the results of a study of spontaneous single electron emission following cosmic muon signals. It was found that the rate of spontaneous single electron signals strongly depends on the time passed since the initial electroluminescence happened. The analysis of experimental data showed that both spontaneous single electron signals and delayed electroluminescent signals are associated with ionization electrons which are trapped by the potential barrier at the interface.

  5. Parameter selection methods of delay and beamforming for cochlear implant speech enhancement

    NASA Astrophysics Data System (ADS)

    Gong, Qin; Chen, Yousheng

    2011-07-01

    Speech acquisition by a cochlear implant (CI) is typically performed by a single omnidirectional microphone. In order to improve the signal-to-noise ratio (SNR) of sound collected from the forward direction, the delay beamforming method is applied to satisfy the size and processing limitations. The optimal delay time and weighting parameters, selected by our proposed graphical method, yielded a beam pattern that strongly enhanced speech from the front, while noise from lateral and rear directions were sharply weakened, making the method appropriate for use in CI applications.

  6. New stability criteria and bifurcation analysis for nonlinear discrete-time coupled loops with multiple delays.

    PubMed

    Peng, Mingshu; Yang, Xiaozhong

    2010-03-01

    A detailed analysis of zero distributions in a special polynomial of the form lambda(tau)(lambda-a(1))(lambda-a(2))...(lambda-a(n))-(c+id) is proposed, where all a(i)(i=1,2,...,) have the same sign. As its applications, new criteria for asymptotic behavior of nonlinear delayed coupled systems with different topological structures are established. All possible bifurcations, including codimension-two bifurcations with 1:4/1:3 strong resonance in such a delayed difference system, are discussed. Numerical simulation gives a solid verification of the theoretical analysis. PMID:20370280

  7. New stability criteria and bifurcation analysis for nonlinear discrete-time coupled loops with multiple delays

    NASA Astrophysics Data System (ADS)

    Peng, Mingshu; Yang, Xiaozhong

    2010-03-01

    A detailed analysis of zero distributions in a special polynomial of the form λτ(λ -a1)(λ -a2)⋯(λ -an)-(c +id) is proposed, where all ai(i =1,2,…,) have the same sign. As its applications, new criteria for asymptotic behavior of nonlinear delayed coupled systems with different topological structures are established. All possible bifurcations, including codimension-two bifurcations with 1:4/1:3 strong resonance in such a delayed difference system, are discussed. Numerical simulation gives a solid verification of the theoretical analysis.

  8. Data Assimilation by delay-coordinate nudging

    NASA Astrophysics Data System (ADS)

    Pazo, Diego; Lopez, Juan Manuel; Carrassi, Alberto

    2016-04-01

    A new nudging method for data assimilation, delay-coordinate nudging, is presented. Delay-coordinate nudging makes explicit use of present and past observations in the formulation of the forcing driving the model evolution at each time-step. Numerical experiments with a low order chaotic system show that the new method systematically outperforms standard nudging in different model and observational scenarios, also when using an un-optimized formulation of the delay-nudging coefficients. A connection between the optimal delay and the dominant Lyapunov exponent of the dynamics is found based on heuristic arguments and is confirmed by the numerical results, providing a guideline for the practical implementation of the algorithm. Delay-coordinate nudging preserves the easiness of implementation, the intuitive functioning and the reduced computational cost of the standard nudging, making it a potential alternative especially in the field of seasonal-to-decadal predictions with large Earth system models that limit the use of more sophisticated data assimilation procedures.

  9. The use of delay in multitrack production

    NASA Astrophysics Data System (ADS)

    Case, Alexander U.

    2003-04-01

    Delay, inevitable whenever sound propagates through space, is too often the bane of the acoustician's practice. An audible echo generally relegates a music performance hall-no matter how beautiful it otherwise might sound-to the lowest status. Multitrack music production on the other hand, with its aggressive use of overdubbing, editing, and signal processing, is not bound by those rules of time and space which determine the sound of a hall. In the recording studio, where music is synthesized for playback over loudspeakers, the delay is employed as a powerful, multipurpose tool. It is not avoided. It is in fact embraced. Echoes are used on purpose, strategically, to enhance the loudspeaker listening experience. Moreover, the humble delay is the basis for many nonecho effects. Flanging, chorus, and pitch shifting are delay-based effects regularly used in audio engineering practice. This paper discusses some of the more common delay-based effects, reviewing their technical structure, the psychoacoustic motivation behind them, and the musical value they create.

  10. Intrinsic delay of permeable base transistor

    SciTech Connect

    Chen, Wenchao; Guo, Jing; So, Franky

    2014-07-28

    Permeable base transistors (PBTs) fabricated by vacuum deposition or solution process have the advantages of easy fabrication and low power operation and are a promising device structure for flexible electronics. Intrinsic delay of PBT, which characterizes the speed of the transistor, is investigated by solving the three-dimensional Poisson equation and drift-diffusion equation self-consistently using finite element method. Decreasing the emitter thickness lowers the intrinsic delay by improving on-current, and a thinner base is also preferred for low intrinsic delay because of fewer carriers in the base region at off-state. The intrinsic delay exponentially decreases as the emitter contact Schottky barrier height decreases, and it linearly depends on the carrier mobility. With an optimized emitter contact barrier height and device geometry, a sub-nano-second intrinsic delay can be achieved with a carrier mobility of ∼10 cm{sup 2}/V/s obtainable in solution processed indium gallium zinc oxide, which indicates the potential of solution processed PBTs for GHz operations.

  11. Recursive delay calculation unit for parametric beamformer

    NASA Astrophysics Data System (ADS)

    Nikolov, Svetoslav I.; Jensen, Jørgen A.; Tomov, Borislav

    2006-03-01

    This paper presents a recursive approach for parametric delay calculations for a beamformer. The suggested calculation procedure is capable of calculating the delays for any image line defined by an origin and arbitrary direction. It involves only add and shift operations making it suitable for hardware implementation. One delaycalculation unit (DCU) needs 4 parameters, and all operations can be implemented using fixed-point arithmetics. An N-channel system needs N+ 1 DCUs per line - one for the distance from the transmit origin to the image point and N for the distances from the image point to each of the receivers. Each DCU recursively calculates the square of the distance between a transducer element and a point on the beamformed line. Then it finds the approximate square root. The distance to point i is used as an initial guess for point i + 1. Using fixed-point calculations with 36-bit precision gives an error in the delay calculations on the order of 1/64 samples, at a sampling frequency of f s = 40 MHz. The circuit has been synthesized for a Virtex II Pro device speed grade 6 in two versions - a pipelined and a non-pipelined producing 150 and 30 million delays per second, respectively. The non-pipelined circuit occupies about 0.5 % of the FPGA resources and the pipelined one about 1 %. When the square root is found with a pipelined CORDIC processor, 2 % of the FPGA slices are used to deliver 150 million delays per second.

  12. Active inference, eye movements and oculomotor delays.

    PubMed

    Perrinet, Laurent U; Adams, Rick A; Friston, Karl J

    2014-12-01

    This paper considers the problem of sensorimotor delays in the optimal control of (smooth) eye movements under uncertainty. Specifically, we consider delays in the visuo-oculomotor loop and their implications for active inference. Active inference uses a generalisation of Kalman filtering to provide Bayes optimal estimates of hidden states and action in generalised coordinates of motion. Representing hidden states in generalised coordinates provides a simple way of compensating for both sensory and oculomotor delays. The efficacy of this scheme is illustrated using neuronal simulations of pursuit initiation responses, with and without compensation. We then consider an extension of the generative model to simulate smooth pursuit eye movements-in which the visuo-oculomotor system believes both the target and its centre of gaze are attracted to a (hidden) point moving in the visual field. Finally, the generative model is equipped with a hierarchical structure, so that it can recognise and remember unseen (occluded) trajectories and emit anticipatory responses. These simulations speak to a straightforward and neurobiologically plausible solution to the generic problem of integrating information from different sources with different temporal delays and the particular difficulties encountered when a system-like the oculomotor system-tries to control its environment with delayed signals. PMID:25128318

  13. Computing using delayed feedback systems: towards photonics

    NASA Astrophysics Data System (ADS)

    Appeltant, L.; Soriano, M. C.; Van der Sande, G.; Danckaert, J.; Massar, S.; Dambre, J.; Schrauwen, B.; Mirasso, C. R.; Fischer, I.

    2012-06-01

    Reservoir computing has recently been introduced as a new paradigm in the eld of machine learning. It is based on the dynamical properties of a network of randomly connected nodes or neurons and shows to be very promising to solve complex classication problems in a computationally ecient way. The key idea is that an input generates nonlinearly transient behavior rendering transient reservoir states suitable for linear classication. Our goal is to study up to which extent systems with delay, and especially photonic systems, can be used as reservoirs. Recently an new architecture has been proposed1 , based on a single nonlinear node with delayed feedback. An electronic1 and an opto-electronic implementation2, 3 have been demonstrated and both have proven to be very successful in terms of performance. This simple conguration, which replaces an entire network of randomly connected nonlinear nodes with one single hardware node and a delay line, is signicantly easier to implement experimentally. It is no longer necessary to construct an entire network of hundreds or even thousands of circuits, each one representing a node. With this approach one node and a delay line suce to construct a computational unit. In this manuscript, we present a further investigation of the properties of delayed feedback congurations used as a reservoir. Instead of quantifying the performance as an error obtained for a certain benchmark, we now investigate a task-independent property, the linear memory of the system.

  14. Time Delay for the Dirac Equation

    NASA Astrophysics Data System (ADS)

    Naumkin, Ivan; Weder, Ricardo

    2016-07-01

    We consider time delay for the Dirac equation. A new method to calculate the asymptotics of the expectation values of the operator {intlimits0 ^{∞}e^{iH0t}ζ(\\vert x\\vert /R) e^{-iH0t}dt} , as {R → ∞} , is presented. Here, H 0 is the free Dirac operator and {ζ(t)} is such that {ζ(t) = 1} for {0 ≤ t ≤ 1} and {ζ(t) = 0} for {t > 1} . This approach allows us to obtain the time delay operator {δ {T}(f)} for initial states f in {{H} 2^{3/2+ɛ}({R}3;{C}4)} , {ɛ > 0} , the Sobolev space of order {3/2+ɛ} and weight 2. The relation between the time delay operator {δ{T}(f)} and the Eisenbud-Wigner time delay operator is given. In addition, the relation between the averaged time delay and the spectral shift function is presented.

  15. Spatiotemporal Control of Light Transmission through a Multimode Fiber with Strong Mode Coupling

    NASA Astrophysics Data System (ADS)

    Xiong, Wen; Ambichl, Philipp; Bromberg, Yaron; Redding, Brandon; Rotter, Stefan; Cao, Hui

    2016-07-01

    We experimentally generate and characterize eigenstates of the Wigner-Smith time-delay matrix, called principal modes, in a multimode fiber with strong mode coupling. The unique spectral and temporal properties of principal modes enable global control of temporal dynamics of optical pulses transmitted through the fiber, despite random mode mixing. Our analysis reveals that well-defined delay times of the eigenstates are formed by multipath interference, which can be effectively manipulated by spatial degrees of freedom of input wave fronts. This study is essential to controlling dynamics of wave scattering, paving the way for coherent control of pulse propagation through complex media.

  16. Progressive Delay and Unlimited Delay of Prompts in Forward Chaining and Whole Task Training Strategies.

    ERIC Educational Resources Information Center

    Walls, Richard T.; And Others

    1984-01-01

    Nineteen vocational rehabilitation clients were trained to assemble 12-part apparatuses via a forward chaining or whole task training sequence with a one-second progressive or an unlimited prompt delay. Less training time but more prompts were required in whole task than in forward chaining conditions. Whole-task unlimited delay yielded most…

  17. A Comparison of Motor Delays in Young Children: Autism Spectrum Disorder, Developmental Delay, and Developmental Concerns

    ERIC Educational Resources Information Center

    Provost, Beth; Lopez, Brian R.; Heimerl, Sandra

    2007-01-01

    This study assessed motor delay in young children 21-41 months of age with autism spectrum disorder (ASD), and compared motor scores in children with ASD to those of children without ASD. Fifty-six children (42 boys, 14 girls) were in three groups: children with ASD, children with developmental delay (DD), and children with developmental concerns…

  18. The Effects of Delay of Feedback on a Delayed Concept Formation Transfer Task.

    ERIC Educational Resources Information Center

    Schroth, Marvin L.

    1992-01-01

    Delay and completeness of verbal information feedback were investigated within a transfer of learning paradigm involving concept formation. An experiment with 192 undergraduates indicates that, although delay of feedback (up to 30 seconds) slows speed of learning on the initial task, it has positive effects on the transfer task. (SLD)

  19. Delay-bandwidth and delay-loss limitations for cloaking of large objects.

    PubMed

    Hashemi, Hila; Zhang, Baile; Joannopoulos, J D; Johnson, Steven G

    2010-06-25

    We show that the difficulty of cloaking is fundamentally limited by delay-loss and delay-bandwidth limitations that worsen as the size of the object to be cloaked increases relative to the wavelength, using a simple model of ground-plane cloaking. These limitations must be considered when scaling experimental cloaking demonstrations up from wavelength-scale objects. PMID:20867381

  20. Effect of Delay on Children's Delay-Execute Prospective Memory Performance

    ERIC Educational Resources Information Center

    Rendell, Peter G.; Vella, Melissa J.; Kliegel, Matthias; Terrett, Gill

    2009-01-01

    To date, little work has been done investigating prospective memory in children, particularly using a delay-execute paradigm. Two experiments were conducted to investigate this issue with children aged 5-11 years. While playing a computer driving game, children's ability to carry out a delayed intention either immediately a target cue appeared or…

  1. Advanced Transport Delay Compensation Algorithms: Results of Delay Measurement and Piloted Performance Tests

    NASA Technical Reports Server (NTRS)

    Guo, Liwen; Cardullo, Frank M.; Kelly, Lon C.

    2007-01-01

    This report summarizes the results of delay measurement and piloted performance tests that were conducted to assess the effectiveness of the adaptive compensator and the state space compensator for alleviating the phase distortion of transport delay in the visual system in the VMS at the NASA Langley Research Center. Piloted simulation tests were conducted to assess the effectiveness of two novel compensators in comparison to the McFarland predictor and the baseline system with no compensation. Thirteen pilots with heterogeneous flight experience executed straight-in and offset approaches, at various delay configurations, on a flight simulator where different predictors were applied to compensate for transport delay. The glideslope and touchdown errors, power spectral density of the pilot control inputs, NASA Task Load Index, and Cooper-Harper rating of the handling qualities were employed for the analyses. The overall analyses show that the adaptive predictor results in slightly poorer compensation for short added delay (up to 48 ms) and better compensation for long added delay (up to 192 ms) than the McFarland compensator. The analyses also show that the state space predictor is fairly superior for short delay and significantly superior for long delay than the McFarland compensator.

  2. Time-Delayed Quantum Feedback Control

    NASA Astrophysics Data System (ADS)

    Grimsmo, Arne L.

    2015-08-01

    A theory of time-delayed coherent quantum feedback is developed. More specifically, we consider a quantum system coupled to a bosonic reservoir creating a unidirectional feedback loop. It is shown that the dynamics can be mapped onto a fictitious series of cascaded quantum systems, where the system is driven by past versions of itself. The derivation of this model relies on a tensor network representation of the system-reservoir time propagator. For concreteness, this general theory is applied to a driven two-level atom scattering into a coherent feedback loop. We demonstrate how delay effects can qualitatively change the dynamics of the atom and how quantum control can be implemented in the presence of time delays.

  3. Time-delayed autosynchronous swarm control.

    PubMed

    Biggs, James D; Bennet, Derek J; Dadzie, S Kokou

    2012-01-01

    In this paper a general Morse potential model of self-propelling particles is considered in the presence of a time-delayed term and a spring potential. It is shown that the emergent swarm behavior is dependent on the delay term and weights of the time-delayed function, which can be set to induce a stationary swarm, a rotating swarm with uniform translation, and a rotating swarm with a stationary center of mass. An analysis of the mean field equations shows that without a spring potential the motion of the center of mass is determined explicitly by a multivalued function. For a nonzero spring potential the swarm converges to a vortex formation about a stationary center of mass, except at discrete bifurcation points where the center of mass will periodically trace an ellipse. The analytical results defining the behavior of the center of mass are shown to correspond with the numerical swarm simulations. PMID:22400623

  4. Time-delayed autosynchronous swarm control

    NASA Astrophysics Data System (ADS)

    Biggs, James D.; Bennet, Derek J.; Dadzie, S. Kokou

    2012-01-01

    In this paper a general Morse potential model of self-propelling particles is considered in the presence of a time-delayed term and a spring potential. It is shown that the emergent swarm behavior is dependent on the delay term and weights of the time-delayed function, which can be set to induce a stationary swarm, a rotating swarm with uniform translation, and a rotating swarm with a stationary center of mass. An analysis of the mean field equations shows that without a spring potential the motion of the center of mass is determined explicitly by a multivalued function. For a nonzero spring potential the swarm converges to a vortex formation about a stationary center of mass, except at discrete bifurcation points where the center of mass will periodically trace an ellipse. The analytical results defining the behavior of the center of mass are shown to correspond with the numerical swarm simulations.

  5. Flight Simulator Visual-Display Delay Compensation

    NASA Technical Reports Server (NTRS)

    Crane, D. Francis

    1981-01-01

    A piloted aircraft can be viewed as a closed-loop man-machine control system. When a simulator pilot is performing a precision maneuver, a delay in the visual display of aircraft response to pilot-control input decreases the stability of the pilot-aircraft system. The less stable system is more difficult to control precisely. Pilot dynamic response and performance change as the pilot attempts to compensate for the decrease in system stability. The changes in pilot dynamic response and performance bias the simulation results by influencing the pilot's rating of the handling qualities of the simulated aircraft. The study reported here evaluated an approach to visual-display delay compensation. The objective of the compensation was to minimize delay-induced change in pilot performance and workload, The compensation was effective. Because the compensation design approach is based on well-established control-system design principles, prospects are favorable for successful application of the approach in other simulations.

  6. Delayed switching applied to memristor neural networks

    NASA Astrophysics Data System (ADS)

    Wang, Frank Z.; Helian, Na; Wu, Sining; Yang, Xiao; Guo, Yike; Lim, Guan; Rashid, Md Mamunur

    2012-04-01

    Magnetic flux and electric charge are linked in a memristor. We reported recently that a memristor has a peculiar effect in which the switching takes place with a time delay because a memristor possesses a certain inertia. This effect was named the "delayed switching effect." In this work, we elaborate on the importance of delayed switching in a brain-like computer using memristor neural networks. The effect is used to control the switching of a memristor synapse between two neurons that fire together (the Hebbian rule). A theoretical formula is found, and the design is verified by a simulation. We have also built an experimental setup consisting of electronic memristive synapses and electronic neurons.

  7. Time-Delayed Quantum Feedback Control.

    PubMed

    Grimsmo, Arne L

    2015-08-01

    A theory of time-delayed coherent quantum feedback is developed. More specifically, we consider a quantum system coupled to a bosonic reservoir creating a unidirectional feedback loop. It is shown that the dynamics can be mapped onto a fictitious series of cascaded quantum systems, where the system is driven by past versions of itself. The derivation of this model relies on a tensor network representation of the system-reservoir time propagator. For concreteness, this general theory is applied to a driven two-level atom scattering into a coherent feedback loop. We demonstrate how delay effects can qualitatively change the dynamics of the atom and how quantum control can be implemented in the presence of time delays. PMID:26296104

  8. Allowable response delay for large aircraft

    NASA Technical Reports Server (NTRS)

    Meyer, R. T.; Tingas, S. A.; Grantham, W. D.

    1984-01-01

    The degree of permissible time delay in an airliner flight control system is presently sought by means of a pilot-in-the-loop moving base flight simulator, assuming the characteristics of an advanced L-1011 aircraft variant. Test pilots and engineers from the U.S. Navy, the airliner manufacturer, and NASA Langley were used in a task which encompassed approach and landing after recovery from offsets in localizer and glide slope, during calm, turbulent, and cross-wind conditions. The data obtained in the course of 279 runs included statistics on pilot workload and performance as well as pilot opinion. Preliminary results indicate that requirements for a 0.1-sec maximum delay in aircraft response are excessively conservative for large aircraft, where an offset landing maneuver is the critical design task. Lateral axis delays appear to be more critical than longitudinal ones.

  9. Time delays in correlated photoemission processes

    NASA Astrophysics Data System (ADS)

    Pazourek, R.; Nagele, S.; Burgdörfer, J.

    2015-09-01

    We theoretically study time-resolved two-photon double ionization (TPDI) of helium as probed by attosecond streaking. We review recent advances in the understanding of the photoelectric effect in the time domain and discuss the differences between one- and two-photon ionization, as well as one- and two-electron emission. We perform exact ab-initio simulations for attosecond streaking experiments in the sequential TPDI regime and compare the results to the two-electron Eisenbud-Wigner-Smith delay for the process. Our calculations directly show that the timing of the emission process sensitively depends on the energy sharing between the two outgoing electrons. In particular, we identify Fano-like interferences in the relative time delay of the two emitted electrons when the sequential ionization channel occurs via intermediate excited ionic (shake-up) states. Furthermore, we find that the photoemission time delays are only weakly dependent on the relative emission angle of the ejected electrons.

  10. Time delay in Swiss cheese gravitational lensing

    SciTech Connect

    Chen, B.; Kantowski, R.; Dai, X.

    2010-08-15

    We compute time delays for gravitational lensing in a flat {Lambda} dominated cold dark matter Swiss cheese universe. We assume a primary and secondary pair of light rays are deflected by a single point mass condensation described by a Kottler metric (Schwarzschild with {Lambda}) embedded in an otherwise homogeneous cosmology. We find that the cosmological constant's effect on the difference in arrival times is nonlinear and at most around 0.002% for a large cluster lens; however, we find differences from time delays predicted by conventional linear lensing theory that can reach {approx}4% for these large lenses. The differences in predicted delay times are due to the failure of conventional lensing to incorporate the lensing mass into the mean mass density of the universe.

  11. Delayed particles in EAS at Akeno

    NASA Technical Reports Server (NTRS)

    Sakuyama, H.; Suzuki, N.; Watanabe, K.; Mizushima, K.

    1985-01-01

    Using two 2.25 square meter fast scintillation detectors, delayed particles in cosmic ray showers (CRS) have been observed at Akeno Observatory. These are set under 1 m concrete and 2.5 cm lead plates respectively. About 2500 CRS are analyzed. The lateral distribution of delayed particles for the CRS size 10 to the 7th power is flatter than that for to the 7th power. The lateral density of delayed particles is almost constant for the size range 2.2 X 10 to the 5th power approx. 10 to the 7th power and increases rapidly above 10 to the 7th power. These facts may suggest change of nuclear interaction at 10 to the 7th power and substantially the existence of heavy particles with long life.

  12. Diagnostic delay in progressive multifocal leukoencephalopathy.

    PubMed

    Miskin, Dhanashri P; Ngo, Long H; Koralnik, Igor J

    2016-05-01

    We investigated delay in diagnosing progressive multifocal leukoencephalopathy (PML). The median time from initial symptom to diagnosis was 74 days (range 1-1643) in 111 PML patients seen at our institution from 1993 to 2015. Another diagnosis was considered before PML in nearly two-thirds, and more than three-quarters of patients suffered from diagnostic delay greater than 1 month, irrespective of their underlying immunosuppressive condition. Extended diagnostic delay occurred more frequently in patients with possible PML, and among HIV (+) patients with higher CD4(+) T-cell counts at symptom onset. Prompt diagnosis may improve survival of PML in so far as immune reconstitution can be effected, and prevent unnecessary interventions. PMID:27231708

  13. Delayed gamma technique for fissile material assay

    SciTech Connect

    Mozin, Vladimir; Tobin, Stephen; Vujie, Jasmina; Hunt, Alan

    2010-01-01

    Research sponsored by the Next Generation Safeguards Initiative are investigating several non-destructive assay techniques for the quantification of fissile plutonium mass in spent nuclear fuel assemblies. AppHcation of the delayed gamma signatures is investigated in this context. The objective of the research is to assess whether the delayed gamma assay instrument can provide sufficient sensitivity, isotope specificity and accuracy as required in nuclear material safeguards. This effort includes theoretical and experimental components for the optimal combination of interrogation parameters. A new modeling algorithm offering a high level of detail was developed specifically for this purpose and was validated in series of benchmark experiments. Preliminary modeling of the delayed gamma response from spent fuel assemblies was accomplished offering a future direction for the design process.

  14. Simple delay monitor for droplet sorters.

    PubMed

    De Grooth, B G; Doornbos, R M; Van Der Werf, K O; Greve, J

    1991-01-01

    We have constructed a simple device by which the optimal delay time between optical measurement of a cell and the application of the droplet charging pulse can be determined directly in a flow sorter. The device consists of a stainless steel chamber in which the sorted droplets are collected. In the collection chamber the collected droplets run through a capillary where a continuous fluorescence measurement is made. With a sample of fluorescent particles, the delay time is optimal when the measured fluorescence is maximal. The measuring volume is always filled with the last droplets sorted (about 3,000). With this device, the setting of the delay time can be done in a few seconds without the need for microscopical verification. The fluorescence in the collection chamber is excited and detected via optical fibers using about 10% of the light of the existing laser from the flow cytometer and an extra photomultiplier. PMID:1935461

  15. Delayed switching applied to memristor neural networks

    SciTech Connect

    Wang, Frank Z.; Yang Xiao; Lim Guan; Helian Na; Wu Sining; Guo Yike; Rashid, Md Mamunur

    2012-04-01

    Magnetic flux and electric charge are linked in a memristor. We reported recently that a memristor has a peculiar effect in which the switching takes place with a time delay because a memristor possesses a certain inertia. This effect was named the ''delayed switching effect.'' In this work, we elaborate on the importance of delayed switching in a brain-like computer using memristor neural networks. The effect is used to control the switching of a memristor synapse between two neurons that fire together (the Hebbian rule). A theoretical formula is found, and the design is verified by a simulation. We have also built an experimental setup consisting of electronic memristive synapses and electronic neurons.

  16. Delay-dependent stability and stabilisation of continuous 2D delayed systems with saturating control

    NASA Astrophysics Data System (ADS)

    Hmamed, Abdelaziz; Kririm, Said; Benzaouia, Abdellah; Tadeo, Fernando

    2016-09-01

    This paper deals with the stabilisation problem of continuous two-dimensional (2D) delayed systems, in the presence of saturations on the control signals. For this, a new delay decomposition approach is proposed to deal with the stability and stabilisation issues. The idea is that the range of variation of each delay is divided into segments, and a specific Lyapunov- Krasovskii functional is used that contains different weight matrices in each segment. Then, based on this approach, new delay-dependent stability and stabilisation criteria for continuous 2D delayed systems are derived. These criteria are less conservative and include some existing results as special cases. Some numerical examples are provided to show that a significant improvement is achieved using the proposed approach.

  17. Improved delay-leaping simulation algorithm for biochemical reaction systems with delays

    NASA Astrophysics Data System (ADS)

    Yi, Na; Zhuang, Gang; Da, Liang; Wang, Yifei

    2012-04-01

    In biochemical reaction systems dominated by delays, the simulation speed of the stochastic simulation algorithm depends on the size of the wait queue. As a result, it is important to control the size of the wait queue to improve the efficiency of the simulation. An improved accelerated delay stochastic simulation algorithm for biochemical reaction systems with delays, termed the improved delay-leaping algorithm, is proposed in this paper. The update method for the wait queue is effective in reducing the size of the queue as well as shortening the storage and access time, thereby accelerating the simulation speed. Numerical simulation on two examples indicates that this method not only obtains a more significant efficiency compared with the existing methods, but also can be widely applied in biochemical reaction systems with delays.

  18. 48 CFR 42.1304 - Government delay of work.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Government delay of work... CONTRACT MANAGEMENT CONTRACT ADMINISTRATION AND AUDIT SERVICES Suspension of Work, Stop-Work Orders, and Government Delay of Work 42.1304 Government delay of work. (a) The clause at 52.242-17, Government Delay...

  19. 48 CFR 42.1304 - Government delay of work.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Government delay of work... CONTRACT MANAGEMENT CONTRACT ADMINISTRATION AND AUDIT SERVICES Suspension of Work, Stop-Work Orders, and Government Delay of Work 42.1304 Government delay of work. (a) The clause at 52.242-17, Government Delay...

  20. 48 CFR 42.1304 - Government delay of work.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Government delay of work... CONTRACT MANAGEMENT CONTRACT ADMINISTRATION AND AUDIT SERVICES Suspension of Work, Stop-Work Orders, and Government Delay of Work 42.1304 Government delay of work. (a) The clause at 52.242-17, Government Delay...

  1. Delayed Recompression for Decompression Sickness: Retrospective Analysis

    PubMed Central

    Hadanny, Amir; Fishlev, Gregori; Bechor, Yair; Bergan, Jacob; Friedman, Mony; Maliar, Amit; Efrati, Shai

    2015-01-01

    Introduction Most cases of decompression sickness (DCS) occur soon after surfacing, with 98% within 24 hours. Recompression using hyperbaric chamber should be administrated as soon as feasible in order to decrease bubble size and avoid further tissue injury. Unfortunately, there may be a significant time delay from surfacing to recompression. The time beyond which hyperbaric treatment is non effective is unclear. The aims of the study were first to evaluate the effect of delayed hyperbaric treatment, initiated more than 48h after surfacing for DCS and second, to evaluate the different treatment protocols. Methods From January 2000 to February 2014, 76 divers had delayed hyperbaric treatment (≥48h) for DCS in the Sagol center for Hyperbaric medicine and Research, Assaf-Harofeh Medical Center, Israel. Data were collected from their medical records and compared to data of 128 patients treated earlier than 48h after surfacing at the same hyperbaric institute. Results There was no significant difference, as to any of the baseline characteristics, between the delayed and early treatment groups. With respect to treatment results, at the delayed treatment divers, complete recovery was achieved in 76% of the divers, partial recovery in 17.1% and no improvement in 6.6%. Similar results were achieved when treatment started early, where 78% of the divers had complete recovery, 15.6% partial recovery and 6.2% no recovery. Delayed hyperbaric treatment using US Navy Table 6 protocol trended toward a better clinical outcome yet not statistically significant (OR=2.786, CI95%[0.896-8.66], p=0.07) compared to standard hyperbaric oxygen therapy of 90 minutes at 2 ATA, irrespective of the symptoms severity at presentation. Conclusions Late recompression for DCS, 48 hours or more after surfacing, has clinical value and when applied can achieve complete recovery in 76% of the divers. It seems that the preferred hyperbaric treatment protocol should be based on US Navy Table 6. PMID

  2. Circadian photoentrainment: parameters of phase delaying.

    PubMed

    DeCoursey, P J

    1986-01-01

    Experiments were carried out using simulated den cages to delineate specific characteristics of phase delaying in circadian photoentrainment of a nocturnal rodent, the flying squirrel. The principal experiments entailed presentation of one to five consecutive 15-min white-light pulses per activity cycle at activity onset to animals free-running in darkness, in order to determine the immediate and final phase-shifting effect. Auxiliary experiments recorded entrainment patterns on light-dark (LD) schedules in the den cages. Phase response curves (PRCs) based on 15-min white-light pulses in standard wheel cages were also constructed for these animals as background information for interpreting the phase-delaying experiments. Exposure of a den animal to light by light sampling at the time of initial arousal from the rest state at circadian time (CT) 12, either by an LD schedule or by a 15-min light pulse, resulted in a return to the nest box for a short rest period. The phase delay occurring after a single light exposure at activity onset was equal to the induced rest, thus suggesting an immediate phase shift. The maximum delay was about 1 1/2 hr/cycle, with the amount of delay related to the number of light exposures. During the photoentrained state on an LD schedule, the activity rhythm of a den-housed animal was essentially free-running on the days following a phase delay. The data are used to expand current models for photoentrainment of circadian activity rhythms in nocturnal rodents. PMID:2979583

  3. Pg-pPg Time Delays from Sparse Networks Using the Time-Frequency Correlation Method

    NASA Astrophysics Data System (ADS)

    Pearce, F.; Lu, R.; Toksoz, M. N.

    2008-12-01

    The arrival times of primary phases generally produce poor estimates of focal depth, particularly for shallow events. While depth phases may be detected at teleseismic distances, no reliable methods currently exist for identifying regional depth phase time delays, such as Pg-pPg. Scattering from crustal heterogeneities obscures the Pg-pPg time delay by producing multiplicative noise within the Pg time window. The theory of Time Reversed Acoustics (TRA) states that the autocorrelation of Pg time windows produces a clear sidelobe at the Pg-pPg time delay. Using large Pg time windows (i.e. including more scattering) and stacking the autocorrelations from an array of receivers improves the reconstruction of the sidelobe at the Pg-pPg time delay. In this paper, we expand the TRA concept to develop the Time-Frequency Correlation (TFC) method for measuring Pg-pPg time delays, which incorporates signal-processing techniques used in Sonar and Radar applications. The TFC method applies a 2D correlation function in time delay and frequency delay to the analytic representation of each Pg time window. Stacking the 2D correlation functions better identifies the sidelobe at the Pg-pPg time delay. Tests of the TFC method on synthetic Pg time windows provide guidance in detecting the Pg-pPg time delays for events with different source time functions, focal depths, and scattering distributions. We apply the TFC method to measure Pg-pPg time delays for 33 local earthquakes from the Southern California Earthquake Data Center (SCEDC) catalog. We include only catalog events with the most accurate locations ('A'), catalog depths between 2 and 16 km (±2 km), and magnitudes between 3.0 and 6.0. For each event, the TFC method uses a station array that is sparse (N < 20), narrow aperture (Δθ < 90°), and located greater than 300 km from the catalog epicenter. The Pg-pPg time delays are converted to focal depths assuming vertical propagation within the SCEDC 3D model at each event

  4. Delay correlation analysis and representation for vital complaint VHDL models

    DOEpatents

    Rich, Marvin J.; Misra, Ashutosh

    2004-11-09

    A method and system unbind a rise/fall tuple of a VHDL generic variable and create rise time and fall time generics of each generic variable that are independent of each other. Then, according to a predetermined correlation policy, the method and system collect delay values in a VHDL standard delay file, sort the delay values, remove duplicate delay values, group the delay values into correlation sets, and output an analysis file. The correlation policy may include collecting all generic variables in a VHDL standard delay file, selecting each generic variable, and performing reductions on the set of delay values associated with each selected generic variable.

  5. Delayed sleep onset in depressed young people

    PubMed Central

    2014-01-01

    Background The circadian abnormality of delayed sleep phase has been suggested to characterise a subgroup of depressed young adults with different risk factors and course of illness. We aim to assess the prevalence and factors, particularly substance use, associated with such delay in a large help-seeking cohort of young people with mental health problems. Methods From a consecutively recruited sample of 802 help-seeking young people, 305 (38%) had at least moderate depressive symptoms (QIDS-C16 >10), sleep data and did not have a chronic severe mental illness. Demographic and clinical characteristics were evaluated through self report and clinical interview. Delayed sleep phase was defined as a sleep onset between the hours of 02:00 a.m. – 06:00 a.m. and the characteristics of this group were compared to normal phase sleepers. Results Delayed sleep onset was reported amongst 18% (n = 56/305) of the depressed group compared to 11% of the non-depressed young people. Amongst the depressed group, delayed sleep onset was associated with tobacco, alcohol and cannabis misuse and short sleep duration (x̅: 5.8 hrs vs. x̅: 7.8 hrs). There were no differences in demographic factors, personality traits or symptoms. Tobacco smoking was very common: In logistic regression analyses only tobacco use (OR 2.28, 95% CI: 1.04 - 5.01) was associated with delayed sleep onset. There was no interaction with age. Conclusions Delayed sleep onset was twice as common in depressed young people as the general population and young people with other mental health problems, and is a potential marker for a subgroup of mood disorders. Those with delayed sleep onset were not more severely depressed but had short sleep duration, a risk for chronic psychological ill health, and higher levels of tobacco use. Nicotine use was common in this group, has biological evidence as a sleep disrupter, and requires specifically addressing in this population. PMID:24506941

  6. [Traumatic diaphragmatic rupture with delayed unusual disclosure].

    PubMed

    Thicoïpé, M; Sztark, F; Lassié, P; Tueux, O; Dabadie, P

    1995-01-01

    The authors report the case of a delayed presentation of a traumatic diaphragmatic rupture in a 22-year-old patient admitted to hospital for a minor surgical procedure under general anaesthesia. Nine months before, he had a road traffic accident with a minor thoracic trauma. Three days after surgery, the patient was readmitted for a tension hydrothorax due to the herniation and the perforation of the stomach into the left pleural cavity. Such a delayed presentation of a traumatic diaphragmatic rupture remains uncommon. The peroperative ventilatory factors involved in the development of the hernia are discussed. PMID:8572411

  7. Time Delays, Bends, Acceleration and Array Reconfigurations

    SciTech Connect

    Faltens, A.

    2011-06-24

    This note was originally one of the parts of the work on a 50 MeV and 500 MeV Rb{sup +} driver and part of work on delay lines for a 60 GeV U{sup +12} driver. It is slightly expanded here to make it more generally applicable. The emphasis is on beam manipulations such as joining and separating beams at the two ends of a driver and providing various time delays between beams as required by the target.

  8. Acoustic emission characterization using AE (parameter) delay

    NASA Technical Reports Server (NTRS)

    Williams, J. H., Jr.; Lee, S. S.

    1983-01-01

    The acoustic emission (AE) parameter delay concept is defined as that particular measured value of a parameter at which a specified baseline level of cumulative AE activity is reached. The parameter can be from any of a broad range of elastic, plastic, viscoelastic, and fracture mechanics parameters, as well as their combinations. Such parameters include stress, load, strain, displacement, time, temperature, loading cycle, unloading stress, stress intensity factor, strain energy release rate, and crack tip plasticity zone size, while the AE activity may be AE event counts, ringdown counts, energy, event duration, etc., as well as their combinations. Attention is given to examples for the AE parameter delay concept, together with various correlations.

  9. Artificial long-delay optical processor

    NASA Astrophysics Data System (ADS)

    Kornreich, Philipp G.; Smith, Jacqueline D.

    1993-02-01

    The Artificial Long Delay Optical Processor (ALDOP) generates a large variable delay of a band limited pulse modulated RF signal. The proposed prototype ALDOP has potential use in a Passive Radio Ranging (PRR) system operating in the 82.5 - 97.5 MHz frequency band. The complete system will combine a passive electronic band pass filter with the optically based ALDOP to impart a unique phase shift to each frequency component of an incoming RF signal. The phase shift is generated using optical heterodyne methods that incorporate the transmission and modulation of light through a series of optical components including an acousto-optical cell and a Fresnel Zone Plate.

  10. Quantitative assessment of meteorological and tropospheric Zenith Hydrostatic Delay models

    NASA Astrophysics Data System (ADS)

    Zhang, Di; Guo, Jiming; Chen, Ming; Shi, Junbo; Zhou, Lv

    2016-09-01

    Tropospheric delay has always been an important issue in GNSS/DORIS/VLBI/InSAR processing. Most commonly used empirical models for the determination of tropospheric Zenith Hydrostatic Delay (ZHD), including three meteorological models and two empirical ZHD models, are carefully analyzed in this paper. Meteorological models refer to UNB3m, GPT2 and GPT2w, while ZHD models include Hopfield and Saastamoinen. By reference to in-situ meteorological measurements and ray-traced ZHD values of 91 globally distributed radiosonde sites, over a four-years period from 2010 to 2013, it is found that there is strong correlation between errors of model-derived values and latitudes. Specifically, the Saastamoinen model shows a systematic error of about -3 mm. Therefore a modified Saastamoinen model is developed based on the "best average" refractivity constant, and is validated by radiosonde data. Among different models, the GPT2w and the modified Saastamoinen model perform the best. ZHD values derived from their combination have a mean bias of -0.1 mm and a mean RMS of 13.9 mm. Limitations of the present models are discussed and suggestions for further improvements are given.

  11. Strong-Field Control of Laser Filamentation Mechanisms

    NASA Astrophysics Data System (ADS)

    Levis, Robert; Romanov, Dmitri; Filin, Aleskey; Compton, Ryan

    2008-05-01

    The propagation of short strong-file laser pulses in gas and solution phases often result in formation of filaments. This phenomenon involves many nonlinear processes including Kerr lensing, group velocity dispersion, multi-photon ionization, plasma defocusing, intensity clamping, and self-steepening. Of these, formation and dynamics of pencil-shape plasma areas plays a crucial role. The fundamental understanding of these laser-induced plasmas requires additional effort, because the process is highly nonlinear and complex. We studied the ultrafast laser-generated plasma dynamics both experimentally and theoretically. Ultrafast plasma dynamics was probed using Coherent Anti-Stokes Raman Scattering. The measurements were made in a room temperature gas maintained at 1 atm in a flowing cell. The time dependent scattering was measured by delaying the CARS probe with respect to the intense laser excitation pulse. A general trend is observed between the spacing of the ground state and the first allowed excited state with the rise time for the noble gas series and the molecular gases. This trend is consistent with our theoretical model, which considers the ultrafast dynamics of the strong field generated plasma as a three-step process; (i) strong-field ionization followed by the electron gaining considerable kinetic energy during the pulse; (ii) immediate post-pulse dynamics: fast thermalization, impact-ionization-driven electron multiplication and cooling; (iii) ensuing relaxation: evolution to electron-ion equilibrium and eventual recombination.

  12. Experimental realization of a delayed-choice quantum walk.

    PubMed

    Jeong, Youn-Chang; Di Franco, Carlo; Lim, Hyang-Tag; Kim, M S; Kim, Yoon-Ho

    2013-01-01

    Many paradoxes of quantum mechanics come from the fact that quantum systems can possess different features simultaneously, such as in wave-particle duality or quantum superposition. In recent delayed-choice experiments, a quantum system can be observed to manifest one feature such as the wave or particle nature, depending on the measurement setup, which is chosen after the system itself has already entered the measuring device; hence its behaviour is not predetermined. Here we adapt this paradigmatic scheme to multi-dimensional quantum walks. In our experiment, the way in which a photon interferes with itself in a strongly non-trivial pattern depends on its polarization, which is determined after the photon has already been detected. This is the first experiment realizing a multi-dimensional quantum walk with a single photon source and we present also the first experimental simulation of the Grover walk, a model that can be used to implement the Grover quantum search algorithm. PMID:24030247

  13. Experimental realization of a delayed-choice quantum walk

    NASA Astrophysics Data System (ADS)

    Jeong, Youn-Chang; di Franco, Carlo; Lim, Hyang-Tag; Kim, M. S.; Kim, Yoon-Ho

    2013-09-01

    Many paradoxes of quantum mechanics come from the fact that quantum systems can possess different features simultaneously, such as in wave-particle duality or quantum superposition. In recent delayed-choice experiments, a quantum system can be observed to manifest one feature such as the wave or particle nature, depending on the measurement setup, which is chosen after the system itself has already entered the measuring device; hence its behaviour is not predetermined. Here we adapt this paradigmatic scheme to multi-dimensional quantum walks. In our experiment, the way in which a photon interferes with itself in a strongly non-trivial pattern depends on its polarization, which is determined after the photon has already been detected. This is the first experiment realizing a multi-dimensional quantum walk with a single photon source and we present also the first experimental simulation of the Grover walk, a model that can be used to implement the Grover quantum search algorithm.

  14. Time delay in the Einstein ring PKS 1830-211

    NASA Technical Reports Server (NTRS)

    Van Ommen, T. D.; Jones, D. L.; Preston, R. A.; Jauncey, D. L.

    1995-01-01

    We present radio observations of the gravitational lens PKS 1830-211 at 8.4 and 15 GHz acquired using the Very Large Array. The observations were made over a 13 month period. Significant flux density changes over this period provide strong constraints on the time delay between the two lensed images and suffest a value of 44 +/- 9 days. This offers new direct evidence that this source is indeed a gravitational lens. The lens distance is dependent upon the model chosen, but reasonable limits on the mass of the lensing galaxy suggest that it is unlikely to be at a redshift less than a few tenths, and may well be significantly more distant.

  15. Distinguishing time-delayed causal interactions using convergent cross mapping

    PubMed Central

    Ye, Hao; Deyle, Ethan R.; Gilarranz, Luis J.; Sugihara, George

    2015-01-01

    An important problem across many scientific fields is the identification of causal effects from observational data alone. Recent methods (convergent cross mapping, CCM) have made substantial progress on this problem by applying the idea of nonlinear attractor reconstruction to time series data. Here, we expand upon the technique of CCM by explicitly considering time lags. Applying this extended method to representative examples (model simulations, a laboratory predator-prey experiment, temperature and greenhouse gas reconstructions from the Vostok ice core, and long-term ecological time series collected in the Southern California Bight), we demonstrate the ability to identify different time-delayed interactions, distinguish between synchrony induced by strong unidirectional-forcing and true bidirectional causality, and resolve transitive causal chains. PMID:26435402

  16. Distinguishing time-delayed causal interactions using convergent cross mapping.

    PubMed

    Ye, Hao; Deyle, Ethan R; Gilarranz, Luis J; Sugihara, George

    2015-01-01

    An important problem across many scientific fields is the identification of causal effects from observational data alone. Recent methods (convergent cross mapping, CCM) have made substantial progress on this problem by applying the idea of nonlinear attractor reconstruction to time series data. Here, we expand upon the technique of CCM by explicitly considering time lags. Applying this extended method to representative examples (model simulations, a laboratory predator-prey experiment, temperature and greenhouse gas reconstructions from the Vostok ice core, and long-term ecological time series collected in the Southern California Bight), we demonstrate the ability to identify different time-delayed interactions, distinguish between synchrony induced by strong unidirectional-forcing and true bidirectional causality, and resolve transitive causal chains. PMID:26435402

  17. Distinguishing time-delayed causal interactions using convergent cross mapping

    NASA Astrophysics Data System (ADS)

    Ye, Hao; Deyle, Ethan R.; Gilarranz, Luis J.; Sugihara, George

    2015-10-01

    An important problem across many scientific fields is the identification of causal effects from observational data alone. Recent methods (convergent cross mapping, CCM) have made substantial progress on this problem by applying the idea of nonlinear attractor reconstruction to time series data. Here, we expand upon the technique of CCM by explicitly considering time lags. Applying this extended method to representative examples (model simulations, a laboratory predator-prey experiment, temperature and greenhouse gas reconstructions from the Vostok ice core, and long-term ecological time series collected in the Southern California Bight), we demonstrate the ability to identify different time-delayed interactions, distinguish between synchrony induced by strong unidirectional-forcing and true bidirectional causality, and resolve transitive causal chains.

  18. Mechanism of intersystem crossing of thermally activated delayed fluorescence molecules.

    PubMed

    Ogiwara, Toshinari; Wakikawa, Yusuke; Ikoma, Tadaaki

    2015-04-01

    The spin sublevel dynamics of the excited triplet state in thermally activated delayed fluorescence (TADF) molecules have not been investigated for high-intensity organic light-emitting diode materials. Understanding the mechanism for intersystem crossing (ISC) is thus important for designing novel TADF materials. We report the first study on the ISC dynamics of the lowest excited triplet state from the lowest excited singlet state with charge-transfer (CT) character of TADF molecules with different external quantum efficiencies (EQEs) using time-resolved electron paramagnetic resonance methods. Analysis of the observed spin polarization indicates a strong correlation of the EQE with the population rate due to ISC induced by hyperfine coupling with the magnetic nuclei. It is concluded that molecules with high EQE have an extremely small energy gap between the (1)CT and (3)CT states, which allows an additional ISC channel due to the hyperfine interactions. PMID:25774790

  19. The STRong-lensing Insights into Dark Energy Survey (STRIDES)

    NASA Astrophysics Data System (ADS)

    Treu, Tommaso; Agnello, Adriano; Strides Team

    2015-01-01

    Recent work has demonstrated that strongly lensed quasars can be used to measure cosmological parameters with high accuracy and precision. The constraints obtained from time delays are comparable in precision to those obtained by baryonic acoustic oscillation experiments and provide a powerful complement to other probes of dark energy like the cosmic microwave background (Suyu et al. 2014). At the moment, a main limitation of this technique is that lensed quasars are rare in the sky and not enough suitable lenses are known. To overcome this challenge we have formed a DES broad external collaboration (STRIDES), aimed at discovering and following-up 100 previously unknown gravitationally lensed quasars. I will present novel search algorithms based on data mining techniques as well as the first results from the search.

  20. Bursting frequency versus phase synchronization in time-delayed neuron networks

    NASA Astrophysics Data System (ADS)

    Nordenfelt, Anders; Used, Javier; Sanjuán, Miguel A. F.

    2013-05-01

    We investigate the dependence of the average bursting frequency on time delay for neuron networks with randomly distributed time-delayed chemical synapses. The result is compared with the corresponding curve for the phase synchronization and it turns out that, in some intervals, these have a very similar shape and appear as almost mirror images of each other. We have analyzed both the map-based chaotic Rulkov model and the continuous Hindmarsh-Rose model, yielding the same conclusions. In order to gain further insight, we also analyzed time-delayed Kuramoto models displaying an overall behavior similar to that observed on the neuron network models. For the Kuramoto models, we were able to derive analytical formulas providing an implicit functional relationship between the mean frequency and the phase synchronization. These formulas suggest a strong dependence between those two measures, which could explain the similarities in shape between the curves.

  1. Type Ia supernovae: Pulsating delayed detonation models, IR light curves, and the formation of molecules

    NASA Technical Reports Server (NTRS)

    Hoflich, Peter; Khokhlov, A.; Wheeler, C.

    1995-01-01

    We computed optical and infrared light curves of the pulsating class of delayed detonation models for Type Ia supernovae (SNe Ia). It is demonstrated that observations of the IR light curves can be used to identify subluminous SNe Ia by testing whether secondary maxima occur in the IR. Our pulsating delayed detonation models are in agreement with current observations both for subluminous and normal bright SN Ia, namely SN1991bg, SN1992bo, and SN1992bc. Observations of molecular bands provide a test to distinguish whether strongly subluminous supernovae are a consequence of the pulsating mechanism occurring in a high-mass white dwarf (WD) or, alternatively, are formed by the helium detonation in a low-mass WD as was suggested by Woosley. In the latter case, no carbon is left after the explosion of low-mass WDs whereas a log of C/O-rich material is present in pulsating delayed detonation models.

  2. Attosecond delay of xenon 4 d photoionization at the giant resonance and Cooper minimum

    NASA Astrophysics Data System (ADS)

    Magrakvelidze, Maia; Madjet, Mohamed El-Amine; Chakraborty, Himadri S.

    2016-07-01

    A Kohn-Sham time-dependent local-density-functional scheme is utilized to predict attosecond time delays of xenon 4 d photoionization that involves the 4 d giant dipole resonance and Cooper minimum. The fundamental effect of electron correlations to uniquely determine the delay at both regions is demonstrated. In particular, for the giant dipole resonance, the delay underpins strong collective effect, emulating the recent prediction at C60 giant plasmon resonance [T. Barillot et al., Phys. Rev. A 91, 033413 (2015), 10.1103/PhysRevA.91.033413]. For the Cooper minimum, a qualitative similarity with a photorecombination experiment near argon 3 p minimum [S. B. Schoun et al., Phys. Rev. Lett. 112, 153001 (2014), 10.1103/PhysRevLett.112.153001] is found. The result should encourage attosecond measurements of Xe 4 d photoemission.

  3. The mechanisms of delayed fluorescence in charge-transfer crystal of tetracyanobenzene-hexamethylbenzene

    NASA Astrophysics Data System (ADS)

    Kozankiewicz, B.; Prochorow, J.

    1989-08-01

    Fluorescence, phosphorescence and delayed fluorescence emission characteristics of tetracyanobenzene-hexamethylbenzene (TCNB-HMB) charge-transfer crystal have been studied in the 1.7-340 K temperature range. Delayed fluorescence, originating from heterogeneous triplet-triplet annihilation indicates the presence of mobile charge-transfer triplet excitons at a temperature as low as 1.7 K. However, the behaviour of triplet excitons in TCNB-HMB crystal is strongly controlled by a very efficient trapping process in the whole temperature range investigated. It was found that thermally activated delayed fluorescence, which is a dominating emission of the crystal at elevated temperatures (>60 K), has a different origin (a different initial state) at different temperatures. These observations were analysed and interpreted in terms of a photokinetic model, which is considered to be typical for charge-transfer crystals with high charge-transfer character of triplet excitons.

  4. Extracting Independent Local Oscillatory Geophysical Signals by Geodetic Tropospheric Delay

    NASA Technical Reports Server (NTRS)

    Botai, O. J.; Combrinck, L.; Sivakumar, V.; Schuh, H.; Bohm, J.

    2010-01-01

    Zenith Tropospheric Delay (ZTD) due to water vapor derived from space geodetic techniques and numerical weather prediction simulated-reanalysis data exhibits non-linear and non-stationary properties akin to those in the crucial geophysical signals of interest to the research community. These time series, once decomposed into additive (and stochastic) components, have information about the long term global change (the trend) and other interpretable (quasi-) periodic components such as seasonal cycles and noise. Such stochastic component(s) could be a function that exhibits at most one extremum within a data span or a monotonic function within a certain temporal span. In this contribution, we examine the use of the combined Ensemble Empirical Mode Decomposition (EEMD) and Independent Component Analysis (ICA): the EEMD-ICA algorithm to extract the independent local oscillatory stochastic components in the tropospheric delay derived from the European Centre for Medium-Range Weather Forecasts (ECMWF) over six geodetic sites (HartRAO, Hobart26, Wettzell, Gilcreek, Westford, and Tsukub32). The proposed methodology allows independent geophysical processes to be extracted and assessed. Analysis of the quality index of the Independent Components (ICs) derived for each cluster of local oscillatory components (also called the Intrinsic Mode Functions (IMFs)) for all the geodetic stations considered in the study demonstrate that they are strongly site dependent. Such strong dependency seems to suggest that the localized geophysical signals embedded in the ZTD over the geodetic sites are not correlated. Further, from the viewpoint of non-linear dynamical systems, four geophysical signals the Quasi-Biennial Oscillation (QBO) index derived from the NCEP/NCAR reanalysis, the Southern Oscillation Index (SOI) anomaly from NCEP, the SIDC monthly Sun Spot Number (SSN), and the Length of Day (LoD) are linked to the extracted signal components from ZTD. Results from the synchronization

  5. Delayed-state-derivative feedback for improving consensus performance of second-order delayed multi-agent systems

    NASA Astrophysics Data System (ADS)

    Wu, Zhihai; Fang, Huajing

    2012-01-01

    In this article, delayed-state-derivative feedback is introduced into the existing delayed consensus protocol for improving the robustness against communication delay and the convergence speed of reaching the consensus simultaneously. Frequency-domain analysis and algebra graph theory are employed to derive the sufficient and necessary condition guaranteeing the second-order delayed multi-agent system applying the consensus protocol with the delayed-state-derivative feedback to achieve the stationary consensus asymptotically. It is proved that introducing delayed-state-derivative feedback with the proper intensity can improve the robustness against communication delay and that for two particular kinds of second-order delayed multi-agent systems, introducing the delayed-state-derivative feedback can also accelerate the convergence speed, provided that the intensity of the delayed-state-derivative feedback is chosen properly. Simulations are provided to demonstrate the effectiveness of the theoretical results.

  6. Response Acquisition by Humans with Delayed Reinforcement

    ERIC Educational Resources Information Center

    Okouchi, Hiroto

    2009-01-01

    The present experiment examined whether a response class was acquired by humans with delayed reinforcement. Eight white circles were presented on a computer touch screen. If the undergraduates touched two of the eight circles in a specified sequence (i.e., touching first the upper-left circle then the bottom-left circle), then the touches…

  7. Pigeons' Discounting of Probabilistic and Delayed Reinforcers

    ERIC Educational Resources Information Center

    Green, Leonard; Myerson, Joel; Calvert, Amanda L.

    2010-01-01

    Pigeons' discounting of probabilistic and delayed food reinforcers was studied using adjusting-amount procedures. In the probability discounting conditions, pigeons chose between an adjusting number of food pellets contingent on a single key peck and a larger, fixed number of pellets contingent on completion of a variable-ratio schedule. In the…

  8. 34 CFR 303.10 - Developmental delay.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Developmental delay. 303.10 Section 303.10 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION EARLY INTERVENTION PROGRAM FOR INFANTS AND TODDLERS...

  9. Delay Discounting and Social Policy Issues

    ERIC Educational Resources Information Center

    Weatherly, Jeffrey N.; Plumm, Karyn M.; Derenne, Adam

    2011-01-01

    The present study used a delay discounting framework to study decisions about six social policy issues and one monetary outcome. For outcomes that nearly all participants discounted, social policies were discounted significantly more than money. A similar result was observed when analyzing all outcomes using data only from participants who…

  10. DIRECT DELAYED RESPONSE PROJECT: SOIL CHARACTERIZATION

    EPA Science Inventory

    A large amount of soil characterization data has been collected as a component of the Direct/Delayed Response Project (DDRP) in the acid rain Aquatic Effects Research Program. n interlaboratory comparison study was undertaken to identify the ability of this data to that obtained ...

  11. Child obesity and motor development delays

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Childhood obesity has been associated with delays in motor development using weight-for-length z-scores and subcutaneous fat. To study this further, percent body fat and motor development were assessed in children ages 3 to 24 months. Included were 455 children with a total of 1882 longitudinal obse...

  12. 14 CFR 1214.106 - Minor delays.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Minor delays. 1214.106 Section 1214.106 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT General Provisions Regarding Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable Customers § 1214.106...

  13. 14 CFR 1214.106 - Minor delays.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Minor delays. 1214.106 Section 1214.106 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT General Provisions Regarding Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable Customers § 1214.106...

  14. 14 CFR 1214.106 - Minor delays.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Minor delays. 1214.106 Section 1214.106 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT General Provisions Regarding Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable Customers § 1214.106...

  15. 14 CFR 1214.106 - Minor delays.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Minor delays. 1214.106 Section 1214.106 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT General Provisions Regarding Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable Customers § 1214.106...

  16. 48 CFR 1252.217-79 - Delays.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... at (TAR) 48 CFR 1217.7001(b) and (c), insert the following clause: Delays (OCT 1994) When during the... or actions of the Government respecting stoppage of work to permit shifting the vessel, stoppage of hot work to permit bunkering, stoppage of work due to embarking or debarking passengers and loading...

  17. 48 CFR 1252.217-79 - Delays.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... at (TAR) 48 CFR 1217.7001(b) and (c), insert the following clause: Delays (OCT 1994) When during the... or actions of the Government respecting stoppage of work to permit shifting the vessel, stoppage of hot work to permit bunkering, stoppage of work due to embarking or debarking passengers and loading...

  18. Delay discounting of saccharin in rhesus monkeys.

    PubMed

    Freeman, Kevin B; Green, Leonard; Myerson, Joel; Woolverton, William L

    2009-10-01

    The value of a reinforcer decreases as the time until its receipt increases, a phenomenon referred to as delay discounting. Although delay discounting of non-drug reinforcers has been studied extensively in a number of species, our knowledge of discounting in non-human primates is limited. In the present study, rhesus monkeys were allowed to choose in discrete trials between 0.05% saccharin delivered in different amounts and with different delays. Indifference points were calculated and discounting functions were established. Discounting functions for saccharin were well described by a hyperbolic function. Moreover, the discounting rates for saccharin in all six monkeys were comparable to those of other non-human animals responding for non-drug reinforcers. Also consistent with other studies of non-human animals, changing the amount of a saccharin reinforcer available after a 10-s delay did not affect its relative subjective value. Discounting functions for saccharin were steeper than we found in a previous study with cocaine, raising the possibility that drugs such as cocaine may be discounted less steeply than non-drug reinforcers. PMID:19540317

  19. Helping Young Children to Delay Gratification

    ERIC Educational Resources Information Center

    Lee, Pai-Lin; Lan, William; Wang, Chiao-Li; Chiu, Hsiu-Yueh

    2008-01-01

    The ability to delay gratification (DG) in young children is vital to their later development. Such ability should be taught as early as possible. One hundred kindergartners (Mean age = 6.11), randomly assigned to three groups; (a) labeling: received the treatment of being labeled as "patient" kids; (b) story-telling: were read a story about the…

  20. A Delay Discounting Model of Psychotherapy Termination

    ERIC Educational Resources Information Center

    Swift, Joshua K.; Callahan, Jennifer L.

    2009-01-01

    Delay discounting (DD) procedures are emerging as an important new method for psychotherapy researchers. In this paper a framework for conceptualizing existing, seemingly discrepant, research findings on termination is introduced and new directions for research are described. To illustrate the value of a DD framework, the common psychotherapy…

  1. Delayed reporting of the rape victim.

    PubMed

    Burgess, A W; Fehder, W P; Hartman, C R

    1995-09-01

    1. Delayed reporting of rape may be due to impaired cognitive processing, altered states of consciousness, or cognitive dissonance. 2. DNA may speak for the victim who does not remember a rape due to being unconscious. 3. Women with psychosis may incorporate a rape into their delusional system. PMID:7500301

  2. 40 CFR 1500.5 - Reducing delay.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Reducing delay. 1500.5 Section 1500.5 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY PURPOSE, POLICY, AND MANDATE § 1500.5 Reducing... do not individually or cumulatively have a significant effect on the human environment (§ 1508.4)...

  3. 40 CFR 1500.5 - Reducing delay.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Reducing delay. 1500.5 Section 1500.5 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY PURPOSE, POLICY, AND MANDATE § 1500.5 Reducing... do not individually or cumulatively have a significant effect on the human environment (§ 1508.4)...

  4. 40 CFR 1500.5 - Reducing delay.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Reducing delay. 1500.5 Section 1500.5 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY PURPOSE, POLICY, AND MANDATE § 1500.5 Reducing... do not individually or cumulatively have a significant effect on the human environment (§ 1508.4)...

  5. Delaying the International Spread of Pandemic Influenza

    PubMed Central

    Cooper, Ben S; Pitman, Richard J; Edmunds, W. John; Gay, Nigel J

    2006-01-01

    Background The recent emergence of hypervirulent subtypes of avian influenza has underlined the potentially devastating effects of pandemic influenza. Were such a virus to acquire the ability to spread efficiently between humans, control would almost certainly be hampered by limited vaccine supplies unless global spread could be substantially delayed. Moreover, the large increases that have occurred in international air travel might be expected to lead to more rapid global dissemination than in previous pandemics. Methods and Findings To evaluate the potential of local control measures and travel restrictions to impede global dissemination, we developed stochastic models of the international spread of influenza based on extensions of coupled epidemic transmission models. These models have been shown to be capable of accurately forecasting local and global spread of epidemic and pandemic influenza. We show that under most scenarios restrictions on air travel are likely to be of surprisingly little value in delaying epidemics, unless almost all travel ceases very soon after epidemics are detected. Conclusions Interventions to reduce local transmission of influenza are likely to be more effective at reducing the rate of global spread and less vulnerable to implementation delays than air travel restrictions. Nevertheless, under the most plausible scenarios, achievable delays are small compared with the time needed to accumulate substantial vaccine stocks. PMID:16640458

  6. Joint moments of proper delay times

    SciTech Connect

    Martínez-Argüello, Angel M.; Martínez-Mares, Moisés; García, Julio C.

    2014-08-15

    We calculate negative moments of the N-dimensional Laguerre distribution for the orthogonal, unitary, and symplectic symmetries. These moments correspond to those of the proper delay times, which are needed to determine the statistical fluctuations of several transport properties through classically chaotic cavities, like quantum dots and microwave cavities with ideal coupling.

  7. Assessing Visual Delays using Pupil Oscillations

    NASA Technical Reports Server (NTRS)

    Mulligan, Jeffrey B.

    2012-01-01

    Stark (1962) demonstrated vigorous pupil oscillations by illuminating the retina with a beam of light focussed to a small spot near the edge of the pupil. Small constrictions of the pupil then are sufficient to completely block the beam, amplifying the normal relationship between pupil area and retinal illuminance. In addition to this simple and elegant method, Stark also investigated more complex feedback systems using an electronic "clamping box" which provided arbitrary gain and phase delay between a measurement of pupil area and an electronically controlled light source. We have replicated Stark's results using a video-based pupillometer to control the luminance of a display monitor. Pupil oscillations were induced by imposing a linear relationship between pupil area and display luminance, with a variable delay. Slopes of the period-vs-delay function for 3 subjects are close to the predicted value of 2 (1.96-2.39), and the implied delays range from 254 to 376 508 to 652 milliseconds. Our setup allows us to extend Stark's work by investigating a broader class of stimuli.

  8. Teaching Speech to Your Language Delayed Child.

    ERIC Educational Resources Information Center

    Rees, Roger J.; Pryor, Jan, Ed.

    1980-01-01

    Intended for parents, the booklet focuses on the speech and language development of children with language delays. The following topics are among those considered: the parent's role in the initial diagnosis of deafness, intellectual handicap, and neurological difficulties; diagnoses and single causes of difficultiy with speech; what to say to…

  9. 17 CFR 230.473 - Delaying amendments.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the following form filed with a registration statement, or as an amendment to a registration statement... on such date or dates as may be necessary to delay the effective date of such registration statement... paragraph (b) of this section that such registration statement shall thereafter become effective...

  10. Impulsivity relates to striatal gray matter volumes in humans: evidence from a delay discounting paradigm

    PubMed Central

    Tschernegg, Melanie; Pletzer, Belinda; Schwartenbeck, Philipp; Ludersdorfer, Philipp; Hoffmann, Uta; Kronbichler, Martin

    2015-01-01

    Time-stable personality traits, such as impulsivity and its relationship with functional and structural brain alterations, have gained much attention in the recent literature. Evidence from functional neuroimaging data implies an association between impulsivity and cortical as well as subcortical areas of the reward system. Discounting future rewards during impulsive decisions can be related to activation in the orbitofrontal cortex and striatum. Cortical structural changes in prefrontal regions have been found for introspective impulsivity measures. The present study focuses on brain regions associated with delay discounting to investigate structural manifestations of trait impulsivity. To test this, seventy subjects underwent structural magnetic resonance imaging (MRI) followed by a behavioral delay discounting task outside of the scanner to measure impulsivity with questions like: “Would you like to have 3€ immediately or 10€ in 5 days?”. The amount of smaller-but-sooner decisions was calculated and used as a measure of behavioral impulsivity. Furthermore, we estimated subject’s individual delay discounting parameter K reflecting the tendency to discount future rewards. Behaviorally, we found strong evidence in favor of a discounting utility model compared to a standard hyperbolic model of choice valuation. Neuronally, we focused on cortical and subcortical brain structure and investigated the association of behavioral impulsivity with delay discounting tendencies and gray matter volume. Voxel-based morphometric analyses showed positive correlations between delay discounting and gray matter volume in the striatum. Additional analyses using Freesurfer provided evidence for a positive correlation between delay discounting and gray matter volume of the caudate. Taken together, our study provides strong evidence for a structural manifestation of time-stable trait impulsivity in the human brain. PMID:26190993

  11. ["Separation delay" on random flap: an experimental and clinical practice on delayed flap].

    PubMed

    Zhao, S Q

    1990-08-01

    A new technique of delayed flap, that is called "Separation delay" by the authors, has succeeded in animal experiment and clinical practice. In the years of 1985-1989, 11 cases of random skin flaps on the patients had been performed with the new method. All the flaps look like table tennis rackets. It's pedicle is very narrow, simultaneously, the flap itself is very large. So it is quite suitable for repairing a neighbouring wound surface. It can be rotated 180 degrees. "The Separation delay" is a handy way without microsurgical technique. It is also an useful and reliable technique for resurfacing wound on plastic and reconstructive surgery. PMID:2086104

  12. Delaying pelvic exams to encourage contraceptive use.

    PubMed

    Donovan, P

    1992-01-01

    The Family Planning Council of Southeastern Pennsylvania created a project called Start Smart, permitting some new adolescent clients to delay blood tests and pelvic exams up to 6 months after their oral contraceptive prescription. The rationale for the trial is the perception that fear of the pelvic exam is one of the reasons why teen women delay coming to medical care for contraception for 1 year on average after becoming sexually active. 5 clinics participated in the pilot trial from November 1988 to March 1990, giving anticipatory counseling and follow-up telephone calls to all young women in the program, and permitting postponement of the medical work-up to certain teens in 3 of the clinics. Special waivers from the Department of Health and Human Services were needed to permit the exception under Title K. These women had a comprehensive family, social, and medical history, weight, height, blood pressure, urinalysis, and pregnancy test. 627 teens aged 11-17 participated in the pilot trail; 90% were already sexually active; 33% had been so for 1 year; 25% had never used contraception. 25% decided to delay pelvic exams and 40% elected to delay blood tests. Most accepted pelvic exams on their 2nd visit. Those who delayed attended the clinic slightly more often than did others. Although there were no significant results, there were also no adverse medical consequences, such as missed sexually transmitted disease infections. The staff participating in this trial thought the teens had an added sense of control over their medical care. PMID:1628718

  13. SHARP - iii. First Use of Adaptive Optics Imaging to Constrain Cosmology with Gravitational Lens Time Delays

    NASA Astrophysics Data System (ADS)

    Chen, Geoff C. F.; Suyu, Sherry H.; Wong, Kenneth C.; Fassnacht, Christopher D.; Chiueh, Tzihong; Halkola, Aleksi; Hu, I. Shing; Auger, Matthew W.; Koopmans, Léon V. E.; Lagattuta, David J.; McKean, John P.; Vegetti, Simona

    2016-08-01

    Accurate and precise measurements of the Hubble constant are critical for testing our current standard cosmological model and revealing possibly new physics. With Hubble Space Telescope (HST) imaging, each strong gravitational lens system with measured time delays can allow one to determine the Hubble constant with an uncertainty of ˜7%. Since HST will not last forever, we explore adaptive-optics (AO) imaging as an alternative that can provide higher angular resolution than HST imaging but has a less stable point spread function (PSF) due to atmospheric distortion. To make AO imaging useful for time-delay-lens cosmography, we develop a method to extract the unknown PSF directly from the imaging of strongly lensed quasars. In a blind test with two mock data sets created with different PSFs, we are able to recover the important cosmological parameters (time-delay distance, external shear, lens mass profile slope, and total Einstein radius). Our analysis of the Keck AO image of the strong lens system RXJ 1131-1231 shows that the important parameters for cosmography agree with those based on HST imaging and modeling within 1-σ uncertainties. Most importantly, the constraint on the model time-delay distance by using AO imaging with 0.045″ resolution is tighter by ˜50% than the constraint of time-delay distance by using HST imaging with 0.09″ when a power-law mass distribution for the lens system is adopted. Our PSF reconstruction technique is generic and applicable to data sets that have multiple nearby point sources, enabling scientific studies that require high-precision models of the PSF.

  14. Failure of delayed feedback deep brain stimulation for intermittent pathological synchronization in Parkinson's disease.

    PubMed

    Dovzhenok, Andrey; Park, Choongseok; Worth, Robert M; Rubchinsky, Leonid L

    2013-01-01

    Suppression of excessively synchronous beta-band oscillatory activity in the brain is believed to suppress hypokinetic motor symptoms of Parkinson's disease. Recently, a lot of interest has been devoted to desynchronizing delayed feedback deep brain stimulation (DBS). This type of synchrony control was shown to destabilize the synchronized state in networks of simple model oscillators as well as in networks of coupled model neurons. However, the dynamics of the neural activity in Parkinson's disease exhibits complex intermittent synchronous patterns, far from the idealized synchronous dynamics used to study the delayed feedback stimulation. This study explores the action of delayed feedback stimulation on partially synchronized oscillatory dynamics, similar to what one observes experimentally in parkinsonian patients. We employ a computational model of the basal ganglia networks which reproduces experimentally observed fine temporal structure of the synchronous dynamics. When the parameters of our model are such that the synchrony is unphysiologically strong, the feedback exerts a desynchronizing action. However, when the network is tuned to reproduce the highly variable temporal patterns observed experimentally, the same kind of delayed feedback may actually increase the synchrony. As network parameters are changed from the range which produces complete synchrony to those favoring less synchronous dynamics, desynchronizing delayed feedback may gradually turn into synchronizing stimulation. This suggests that delayed feedback DBS in Parkinson's disease may boost rather than suppress synchronization and is unlikely to be clinically successful. The study also indicates that delayed feedback stimulation may not necessarily exhibit a desynchronization effect when acting on a physiologically realistic partially synchronous dynamics, and provides an example of how to estimate the stimulation effect. PMID:23469272

  15. Effects of stomatal delays on the economics of leaf gas exchange under intermittent light regimes.

    PubMed

    Vico, Giulia; Manzoni, Stefano; Palmroth, Sari; Katul, Gabriel

    2011-11-01

    • Understory plants are subjected to highly intermittent light availability and their leaf gas exchanges are mediated by delayed responses of stomata and leaf biochemistry to light fluctuations. In this article, the patterns in stomatal delays across biomes and plant functional types were studied and their effects on leaf carbon gains and water losses were quantified. • A database of more than 60 published datasets on stomatal responses to light fluctuations was assembled. To interpret these experimental observations, a leaf gas exchange model was developed and coupled to a novel formulation of stomatal movement energetics. The model was used to test whether stomatal delays optimize light capture for photosynthesis, whilst limiting transpiration and carbon costs for stomatal movement. • The data analysis showed that stomatal opening and closing delays occurred over a limited range of values and were strongly correlated. Plant functional type and climate were the most important drivers of stomatal delays, with faster responses in graminoids and species from dry climates. • Although perfectly tracking stomata would maximize photosynthesis and minimize transpiration at the expense of large opening costs, the observed combinations of opening and closure times appeared to be consistent with a near-optimal balance of carbon gain, water loss and movement costs. PMID:21851359

  16. A NEW CHANNEL FOR DETECTING DARK MATTER SUBSTRUCTURE IN GALAXIES: GRAVITATIONAL LENS TIME DELAYS

    SciTech Connect

    Keeton, Charles R.; Moustakas, Leonidas A.

    2009-07-10

    We show that dark matter substructure in galaxy-scale halos perturbs the time delays between images in strong gravitational lens systems. The variance of the effect depends on the subhalo mass function, scaling as the product of the substructure mass fraction, and a characteristic mass of subhalos (namely (m {sup 2})/(m)). Time delay perturbations therefore complement gravitational lens flux ratio anomalies and astrometric perturbations by measuring a different moment of the subhalo mass function. Unlike flux ratio anomalies, 'time delay millilensing' is unaffected by dust extinction or stellar microlensing in the lens galaxy. Furthermore, we show that time delay ratios are immune to the radial profile degeneracy that usually plagues lens modeling. We lay out a mathematical theory of time delay perturbations and find it to be tractable and attractive. We predict that in 'cusp' lenses with close triplets of images, substructure may change the arrival-time order of the images (compared with smooth models). We discuss the possibility that this effect has already been observed in RX J1131-1231.

  17. Reprint of: The role of delay times in subcycle-resolved probe retardation measurements

    NASA Astrophysics Data System (ADS)

    Reislöhner, Jan; Pfeiffer, Adrian N.

    2016-08-01

    The delay in the nonlinear response of matter to intense laser pulses has been studied since a long time regarding its nuclear contribution. In contrast, the electronic part of the nonlinear response in wide-band-gap dielectrics, which is usually dominant, is not well explored regarding its delay, and previous studies have revealed that the timescale is below 1 fs. Here, the influence of delay times on the recently introduced method of subcycle-resolved probe retardation measurements is investigated using a simulation. In the model assumed, the electronic nonlinearity is divided into the third order Kerr effect and the plasma contribution due to conduction band population in the strong laser field. In the regime of close-to-collinear pump-probe geometries, the probe retardation shows both π- and 2π-oscillations in the pump-probe delay. Sub-femtosecond delay times influence the phase of the oscillations significantly, but it remains difficult to distinguish the influence of the Kerr response from the plasma contribution.

  18. Influence of Delay Period Duration on Inhibitory Processes for Response Preparation.

    PubMed

    Lebon, Florent; Greenhouse, Ian; Labruna, Ludovica; Vanderschelden, Benjamin; Papaxanthis, Charalambos; Ivry, Richard B

    2016-06-01

    In this study, we examined the dynamics of inhibitory preparatory processes, using a delayed response task in which a cue signaled a left or right index finger (Experiment 1) or hand (Experiment 2) movement in advance of an imperative signal. In Experiment 1, we varied the duration of the delay period (200, 500, and 900 ms). When transcranial magnetic stimulation (TMS) was applied 100 ms before the imperative, motor evoked potentials (MEPs) elicited in the first dorsal interosseous were strongly inhibited. For delays of 500 ms or longer, this inhibition was greater when the targeted muscle was selected compared with when it was not selected. In contrast, the magnitude of inhibition just after the cue was inversely related to the duration of the delay period, and the difference between the selected and nonselected conditions was attenuated. In Experiment 2, TMS and peripheral nerve stimulation procedures were used during a 300-ms delay period. MEPs in the flexor carpi radialis for both selected and nonselected conditions were inhibited, but without any change in the H-reflex. Taken together, these results reveal the dual influence of temporal constraints associated with anticipation and urgency on inhibitory processes recruited during response preparation. PMID:25882038

  19. Robust optimization for nonlinear time-delay dynamical system of dha regulon with cost sensitivity constraint in batch culture

    NASA Astrophysics Data System (ADS)

    Yuan, Jinlong; Zhang, Xu; Liu, Chongyang; Chang, Liang; Xie, Jun; Feng, Enmin; Yin, Hongchao; Xiu, Zhilong

    2016-09-01

    Time-delay dynamical systems, which depend on both the current state of the system and the state at delayed times, have been an active area of research in many real-world applications. In this paper, we consider a nonlinear time-delay dynamical system of dha-regulonwith unknown time-delays in batch culture of glycerol bioconversion to 1,3-propanediol induced by Klebsiella pneumonia. Some important properties and strong positive invariance are discussed. Because of the difficulty in accurately measuring the concentrations of intracellular substances and the absence of equilibrium points for the time-delay system, a quantitative biological robustness for the concentrations of intracellular substances is defined by penalizing a weighted sum of the expectation and variance of the relative deviation between system outputs before and after the time-delays are perturbed. Our goal is to determine optimal values of the time-delays. To this end, we formulate an optimization problem in which the time delays are decision variables and the cost function is to minimize the biological robustness. This optimization problem is subject to the time-delay system, parameter constraints, continuous state inequality constraints for ensuring that the concentrations of extracellular and intracellular substances lie within specified limits, a quality constraint to reflect operational requirements and a cost sensitivity constraint for ensuring that an acceptable level of the system performance is achieved. It is approximated as a sequence of nonlinear programming sub-problems through the application of constraint transcription and local smoothing approximation techniques. Due to the highly complex nature of this optimization problem, the computational cost is high. Thus, a parallel algorithm is proposed to solve these nonlinear programming sub-problems based on the filled function method. Finally, it is observed that the obtained optimal estimates for the time-delays are highly satisfactory

  20. Functional Delay of Myelination of Auditory Delay Lines in the Nucleus Laminaris of the Barn Owl

    PubMed Central

    Cheng, Shih-Min; Carr, Catherine E.

    2012-01-01

    In the barn owl, maps of interaural time difference (ITD) are created in the nucleus laminaris (NL) by interdigitating axons that act as delay lines. Adult delay line axons are myelinated, and this myelination is timely, coinciding with the attainment of adult head size, and stable ITD cues. The proximal portions of the axons become myelinated in late embryonic life, but the delay line portions of the axon in NL remain unmyelinated until the first postnatal week. Myelination of the delay lines peaks at the third week posthatch, and myelinating oligodendrocyte density approaches adult levels by one month, when the head reaches its adult width. Migration of oligodendrocyte progenitors into NL and the subsequent onset of myelination may be restricted by a glial barrier in late embryonic stages and the first posthatch week, since the loss of tenascin-C immunoreactivity in NL is correlated with oligodendrocyte progenitor migration into NL. PMID:17918244

  1. Stability domains of the delay and PID coefficients for general time-delay systems

    NASA Astrophysics Data System (ADS)

    Almodaresi, Elham; Bozorg, Mohammad; Taghirad, Hamid D.

    2016-04-01

    Time delays are encountered in many physical systems, and they usually threaten the stability and performance of closed-loop systems. The problem of determining all stabilising proportional-integral-derivative (PID) controllers for systems with perturbed delays is less investigated in the literature. In this study, the Rekasius substitution is employed to transform the system parameters to a new space. Then, the singular frequency (SF) method is revised for the Rekasius transformed system. A novel technique is presented to compute the ranges of time delay for which stable PID controller exists. This stability range cannot be readily computed from the previous methods. Finally, it is shown that similar to the original SF method, finite numbers of singular frequencies are sufficient to compute the stable regions in the space of time delay and controller coefficients.

  2. On computation of stabilizing loop gain and delay ranges for bi-proper delay systems.

    PubMed

    Le, Binh Nguyen; Wang, Qing-Guo; Lee, Tong Heng; Nie, Zhuoyun

    2014-11-01

    A graphical method for exactly computing the stabilizing loop gain and delay ranges was proposed [Le BN, Wang Q-G, Lee T-H. Development of D-decomposition method for computing stabilizing gain ranges for general delay systems. J Process Control 2012] for a strictly proper process by determining the boundary functions which may change system׳s stability. A bi-proper process is rare but causes great complications for the method, due to the new phenomena that do not exist for a strictly proper process, such as a non-zero gain at infinity frequency, which may cause infinite intersections of boundary functions within a finite delay range. This paper addresses such a kind of processes and develops a general method that can produce the exact and complete set of the loop gain and delay for closed-loop stabilization, which is hard to find with analytical methods. PMID:25440948

  3. A novel delay-dependent criterion for delayed neural networks of neutral type

    NASA Astrophysics Data System (ADS)

    Lee, S. M.; Kwon, O. M.; Park, Ju H.

    2010-04-01

    This Letter considers a robust stability analysis method for delayed neural networks of neutral type. By constructing a new Lyapunov functional, a novel delay-dependent criterion for the stability is derived in terms of LMIs (linear matrix inequalities). A less conservative stability criterion is derived by using nonlinear properties of the activation function of the neural networks. Two numerical examples are illustrated to show the effectiveness of the proposed method.

  4. Delay discounting and self-reported impulsivity in adolescent smokers and nonsmokers living in rural Appalachia.

    PubMed

    Lewis, Russell; Harris, Millie; Slone, Stacey A; Shelton, Brent J; Reynolds, Brady

    2015-09-01

    Background and Objectives This study evaluated whether impulsivity (delay discounting and BIS-11-A) is associated with adolescent smoking status in a region with strong environmental risk factors for smoking. Methods Forty-two adolescent smokers and nonsmokers from rural Appalachia completed discounting and self-reported impulsivity assessments. Results The BIS-11-A, but not the measure of discounting, was associated with smoking status; however, neither assessment predicted smoking status once parent/best-friend smoking variables were statistically accounted for. Discussion and Conclusions In regions with strong environmental risk factors for smoking, delay discounting may play a more limited role in risk of initiation. Scientific Significance Helps to better define impulsivity as risk factors for smoking in relation to familial and broader cultural variables. PMID:26039514

  5. Molecular alignment and filamentation: Comparison between weak- and strong-field models

    NASA Astrophysics Data System (ADS)

    Berti, N.; Béjot, P.; Wolf, J.-P.; Faucher, O.

    2014-11-01

    The impact of nonadiabatic laser-induced molecular alignment on filamentation is numerically studied. Weak- and strong-field models of impulsive molecular alignment are compared in the context of nonlinear pulse propagation. It is shown that the widely used weak-field model describing the refractive index modification induced by impulsive molecular alignment accurately reproduces the propagation dynamics providing that only a single pulse is involved during the experiment. On the contrary, it fails at reproducing the nonlinear propagation experienced by an intense laser pulse traveling in the wake of a second strong laser pulse. The discrepancy depends on the relative delay between the two pulses and is maximal for delays corresponding to half the rotational period of the molecule.

  6. Minimum expected delay-based routing protocol (MEDR) for Delay Tolerant Mobile Sensor Networks.

    PubMed

    Feng, Yong; Liu, Ming; Wang, Xiaomin; Gong, Haigang

    2010-01-01

    It is a challenging work to develop efficient routing protocols for Delay Tolerant Mobile Sensor Networks (DTMSNs), which have several unique characteristics such as sensor mobility, intermittent connectivity, energy limit, and delay tolerability. In this paper, we propose a new routing protocol called Minimum Expected Delay-based Routing (MEDR) tailored for DTMSNs. MEDR achieves a good routing performance by finding and using the connected paths formed dynamically by mobile sensors. In MEDR, each sensor maintains two important parameters: Minimum Expected Delay (MED) and its expiration time. According to MED, messages will be delivered to the sensor that has at least a connected path with their hosting nodes, and has the shortest expected delay to communication directly with the sink node. Because of the changing network topology, the path is fragile and volatile, so we use the expiration time of MED to indicate the valid time of the path, and avoid wrong transmissions. Simulation results show that the proposed MEDR achieves a higher message delivery ratio with lower transmission overhead and data delivery delay than other DTMSN routing approaches. PMID:22163658

  7. Stochastic parameter estimation in nonlinear time-delayed vibratory systems with distributed delay

    NASA Astrophysics Data System (ADS)

    Torkamani, Shahab; Butcher, Eric A.

    2013-07-01

    The stochastic estimation of parameters and states in linear and nonlinear time-delayed vibratory systems with distributed delay is explored. The approach consists of first employing a continuous time approximation to approximate the delayed integro-differential system with a large set of ordinary differential equations having stochastic excitations. Then the problem of state and parameter estimation in the resulting stochastic ordinary differential system is represented as an optimal filtering problem using a state augmentation technique. By adapting the extended Kalman-Bucy filter to the augmented filtering problem, the unknown parameters of the time-delayed system are estimated from noise-corrupted, possibly incomplete measurements of the states. Similarly, the upper bound of the distributed delay can also be estimated by the proposed technique. As an illustrative example to a practical problem in vibrations, the parameter, delay upper bound, and state estimation from noise-corrupted measurements in a distributed force model widely used for modeling machine tool vibrations in the turning operation is investigated.

  8. Fe-rich glass covered amorphous wires used as magnetostrictive delay lines

    NASA Astrophysics Data System (ADS)

    Chiriac, H.; Hristoforou, E.; Neagu, Maria; Darie, I.

    1999-05-01

    Results concerning the response of the magnetostrictive delay line made of Fe 77.5Si 7.5B 15 amorphous glass covered wires are presented. The pulsed voltage output is not significant for glass covered wires but strongly increases after glass removal. The dependence of the pulsed voltage output on the bias magnetic field applied in exciting or receiving points is non-monotonic.

  9. Delayed iatrogenic diaphragmatic hernia after thoracoscopic lobectomy

    PubMed Central

    Pan, Sai-Bo; Zhang, Jian-Bin; Zhao, Bai-Qin

    2016-01-01

    Postoperative iatrogenic diaphragmatic hernia after thoracoscopic lobectomy is extremely rare. We present a 55-year-old female patient who developed an iatrogenic diaphragmatic hernia with gastric perforation several months after VATS (video-assisted thoracic surgery) left upper lobectomy with systematic lymphadenectomy. During the readmission, urgent laparotomy was performed. Intraoperatively, the choledochoscopy was introduced into left thoracic cavity through the diaphragmatic defect for dissecting the secondary inflammatory adhesions and achieving satisfactory hemostasis. It appears to be an efficient and feasible approach for the patients who have been diagnosed as delayed diaphragmatic hernia concomitant with remarkable intra-abdominal findings and have a history of thoracic surgery. We consider that delayed-onset diaphragmatic hernia should be suspected in patients complaining of nausea or vomiting after VATS procedure, although it is very rare. PMID:27293866

  10. Learning Delayed Influences of Biological Systems

    PubMed Central

    Ribeiro, Tony; Magnin, Morgan; Inoue, Katsumi; Sakama, Chiaki

    2015-01-01

    Boolean networks are widely used model to represent gene interactions and global dynamical behavior of gene regulatory networks. To understand the memory effect involved in some interactions between biological components, it is necessary to include delayed influences in the model. In this paper, we present a logical method to learn such models from sequences of gene expression data. This method analyzes each sequence one by one to iteratively construct a Boolean network that captures the dynamics of these observations. To illustrate the merits of this approach, we apply it to learning real data from bioinformatic literature. Using data from the yeast cell cycle, we give experimental results and show the scalability of the method. We show empirically that using this method we can handle millions of observations and successfully capture delayed influences of Boolean networks. PMID:25642421

  11. Wheeler thought experiment with delayed choice

    NASA Astrophysics Data System (ADS)

    Boyd, Jeffrey

    2012-02-01

    This is an alternative interpretation of Jacques, et. al. (2007), Wheeler's thought experiment with delayed choice. The researchers find that the choice of observables changes the previous behavior of the photon inside the interferometer. Stepping outside the QM box, we propose that elementary waves from the detectors travel backwards through the interferometer, and the photon is following such a ray in the reverse direction. Thus a change in observables changes the behavior of the photon for the simple reason that the observable is transmitting information to the photon and the photon is able to change its polarization mid-stream in response to a change in that information. According to this explanation there is no delayed choice. It is an illusion.

  12. Corticosteroid sensitivity in gliomatosis cerebri delays diagnosis

    PubMed Central

    Bittar, Jan; Kamiya-Matsuoka, Carlos; Barata, Pedro C.; Lee-Kim, Soo-Hyun; Olar, Adriana; Tremont-Lukats, Ivo W.

    2015-01-01

    Purpose To describe a patient whose diagnosis of gliomatosis cerebri was delayed for one year due mostly to dexamethasone. Patients and Methods A 78-year-old woman was followed in clinic for a year with a brain lesion suspicious but not definitive for glioma, whose clinical course and neuroimaging varied with use of dexamethasone. A first biopsy and MR spectroscopy did not find evidence of malignancy. Results A second biopsy demonstrated the correct diagnosis when the patient was on a very low dexamethasone dose. Hypercellularity and a positive KI-67 immunostaining confirmed a grade II astrocytoma, although the rapid and aggressive course without dexamethasone suggested a higher grade tumor. Conclusion As in primary CNS lymphoma, the diagnosis of gliomatosis cerebri can be unnecessarily delayed with dexamethasone use. Every effort should be made to biopsy these lesions before or shortly after the addition of dexamethasone. PMID:25922538

  13. Delayed auditory feedback in polyglot simultaneous interpreters.

    PubMed

    Fabbro, F; Darò, V

    1995-03-01

    Twelve polyglot students of simultaneous interpretation and 12 controls (students of the faculty of Medicine) were submitted to a task of verbal fluency under amplified normal auditory feedback (NAF) and under three delayed auditory feedback (DAF) conditions with three different delay intervals (150, 200, and 250 msec). The control group showed a significant reduction in verbal fluency and a significant increase in the number of mistakes in all three DAF conditions. The interpreters' group, however, did not show any significant speech disruption neither in the subjects' mother tongue (L1) nor in their second language (L2) across all DAF conditions. Interpreters' general high verbal fluency along with their ability to pay less attention to their own verbal output make them more resistant to the interfering effects of DAF on speech. PMID:7757448

  14. Delayed onset muscle soreness: is massage effective?

    PubMed

    Nelson, Nicole

    2013-10-01

    Despite the widespread occurrence of delayed onset muscle soreness (DOMS), there is little consensus as to the exact cause or which treatments may be most effective at alleviating symptoms. Greater understanding of DOMS can give sports medicine and fitness professionals an opportunity to help prevent or speed recovery of this performance limiting condition. This article will review the DOMS literature, including the potential role of psychosocial factors and explore studies which involve massage therapy as a treatment modality. Articles from PubMed, MEDLINE, Google Scholar, and references from articles are included in this review. Search words and phrases included delayed onset muscle soreness, repeated bout effect, massage effectiveness, exercise induced muscle damage, and eccentric exercise. PMID:24139006

  15. Fundamentals of Delayed Coking Joint Industry Project

    SciTech Connect

    Michael Volk; Keith Wisecarver

    2003-09-26

    Delayed coking evolved steadily over the early to mid 1900s to enable refiners to convert high boiling, residual petroleum fractions to light products such as gasoline. Pound for pound, coking is the most energy intensive of any operation in a modern refinery. Large amounts of energy are required to heat the thick, poor-quality petroleum residuum to the 900 to 950 degrees F required to crack the heavy hydrocarbon molecules into lighter, more valuable products. One common misconception of delayed coking is that the product coke is a disadvantage. Although coke is a low valued (near zero economic value) byproduct, compared to transportation fuels, there is a significant worldwide trade and demand for coke as it is an economical fuel. Coke production has increased steadily over the last ten years, with further increases forecast for the foreseeable future. Current domestic production is near 111,000 tons per day. A major driving force behind this increase is the steady decline in crude quality available to refiners. Crude slates are expected to grow heavier with higher sulfur contents while environmental restrictions are expected to significantly reduce the demand for high-sulfur residual fuel oil. Light sweet crudes will continue to be available and in even greater demand than they are today. Refiners will be faced with the choice of purchasing light sweet crudes at a premium price, or adding bottom of the barrel upgrading capability, through additional new investments, to reduce the production of high-sulfur residual fuel oil and increase the production of low-sulfur distillate fuels. A second disadvantage is that liquid products from cokers frequently are unstable, i.e., they rapidly form gum and sediments. Because of intermediate investment and operating costs, delayed coking has increased in popularity among refiners worldwide. Based on the 2000 Worldwide Refining Survey published in the Oil and Gas, the delayed coking capacity for 101 refineries around the world

  16. Fundamentals of Delayed Coking Joint Industry Project

    SciTech Connect

    Michael Volk; Keith Wisecarver

    2004-09-26

    Delayed coking evolved steadily over the early to mid 1900s to enable refiners to convert high boiling, residual petroleum fractions to light products such as gasoline. Pound for pound, coking is the most energy intensive of any operation in a modern refinery. Large amounts of energy are required to heat the thick, poor-quality petroleum residuum to the 900 to 950 degrees F required to crack the heavy hydrocarbon molecules into lighter, more valuable products. One common misconception of delayed coking is that the product coke is a disadvantage. Although coke is a low valued (near zero economic value) byproduct, compared to transportation fuels, there is a significant worldwide trade and demand for coke as it is an economical fuel. Coke production has increased steadily over the last ten years, with further increases forecast for the foreseeable future. Current domestic production is near 111,000 tons per day. A major driving force behind this increase is the steady decline in crude quality available to refiners. Crude slates are expected to grow heavier with higher sulfur contents while environmental restrictions are expected to significantly reduce the demand for high-sulfur residual fuel oil. Light sweet crudes will continue to be available and in even greater demand than they are today. Refiners will be faced with the choice of purchasing light sweet crudes at a premium price, or adding bottom of the barrel upgrading capability, through additional new investments, to reduce the production of high-sulfur residual fuel oil and increase the production of low-sulfur distillate fuels. A second disadvantage is that liquid products from cokers frequently are unstable, i.e., they rapidly form gum and sediments. Because of intermediate investment and operating costs, delayed coking has increased in popularity among refiners worldwide. Based on the 2000 Worldwide Refining Survey published in the Oil and Gas, the delayed coking capacity for 101 refineries around the world

  17. Acceleration feedback improves balancing against reflex delay

    PubMed Central

    Insperger, Tamás; Milton, John; Stépán, Gábor

    2013-01-01

    A model for human postural balance is considered in which the time-delayed feedback depends on position, velocity and acceleration (proportional–derivative–acceleration (PDA) feedback). It is shown that a PDA controller is equivalent to a predictive controller, in which the prediction is based on the most recent information of the state, but the control input is not involved into the prediction. A PDA controller is superior to the corresponding proportional–derivative controller in the sense that the PDA controller can stabilize systems with approximately 40 per cent larger feedback delays. The addition of a sensory dead zone to account for the finite thresholds for detection by sensory receptors results in highly intermittent, complex oscillations that are a typical feature of human postural sway. PMID:23173196

  18. Supervising Remote Humanoids Across Intermediate Time Delay

    NASA Technical Reports Server (NTRS)

    Hambuchen, Kimberly; Bluethmann, William; Goza, Michael; Ambrose, Robert; Rabe, Kenneth; Allan, Mark

    2006-01-01

    The President's Vision for Space Exploration, laid out in 2004, relies heavily upon robotic exploration of the lunar surface in early phases of the program. Prior to the arrival of astronauts on the lunar surface, these robots will be required to be controlled across space and time, posing a considerable challenge for traditional telepresence techniques. Because time delays will be measured in seconds, not minutes as is the case for Mars Exploration, uploading the plan for a day seems excessive. An approach for controlling humanoids under intermediate time delay is presented. This approach uses software running within a ground control cockpit to predict an immersed robot supervisor's motions which the remote humanoid autonomously executes. Initial results are presented.

  19. Modeling Weather Impact on Ground Delay Programs

    NASA Technical Reports Server (NTRS)

    Wang, Yao; Kulkarni, Deepak

    2011-01-01

    Scheduled arriving aircraft demand may exceed airport arrival capacity when there is abnormal weather at an airport. In such situations, Federal Aviation Administration (FAA) institutes ground-delay programs (GDP) to delay flights before they depart from their originating airports. Efficient GDP planning depends on the accuracy of prediction of airport capacity and demand in the presence of uncertainties in weather forecast. This paper presents a study of the impact of dynamic airport surface weather on GDPs. Using the National Traffic Management Log, effect of weather conditions on the characteristics of GDP events at selected busy airports is investigated. Two machine learning methods are used to generate models that map the airport operational conditions and weather information to issued GDP parameters and results of validation tests are described.

  20. Delayed diagnosis of adult indolent systemic mastocytosis.

    PubMed

    Mikkelsen, Carsten Sauer; Nybo, Andrew; Arvesen, Kristian Bakke; Holk-Poulsen, Johan

    2014-02-17

    Systemic mastocytosis (SM) is a rare, heterogeneous disorder characterized by infiltration and accumulation of mast cells within multiple organs, most commonly the skin. Given the rarity of the disease and the fact that many of its symptoms are shared by more common disorders, a diagnosis may be delayed or hindered. These patients have an elevated risk of developing potentially life-threatening anaphylactoid reactions, thus underscoring the importance of keeping SM in mind as a differential diagnosis when a patient presents with chronic, itchy skin lesions and a history of multiple allergic reactions to bites, drugs, and anesthesia. We present a case illustrating that features of SM common to many disorders may hinder or delay its diagnosis. PMID:25386326

  1. How we perform delayed enhancement imaging.

    PubMed

    Kim, Raymond J; Shah, Dipan J; Judd, Robert M

    2003-07-01

    Recently, numerous studies have demonstrated the effectiveness of a segmented inversion recovery fast gradient echo (seg IR-FGE) sequence for differentiating injured from normal myocardium. This technique for delayed enhancement imaging has been shown to be effective in identifying the presence and extent of myocardial infarction, as well as predicting improvement in contractile function after coronary revascularization. In this article we outline the procedure of delayed enhancement imaging performed at our center, describe the seg IR-FGE sequence in more detail, including our process for choosing sequence settings, review our process of image interpretation, and highlight potential pitfalls (and techniques to overcome them) that we have encountered in our experience with performing the technique in over 1500 patients. PMID:12882082

  2. Delayed cyanide poisoning following acetonitrile ingestion.

    PubMed Central

    Mueller, M.; Borland, C.

    1997-01-01

    Acetonitrile (methyl cyanide) is a common industrial organic solvent but is a rare cause of poisoning. We report the first recorded UK case. Acetonitrile is slowly converted to cyanide, resulting in delayed toxicity. We describe a case of deliberate self-poisoning by a 39-year-old woman resulting in cyanide poisoning 11 hours later which was successfully treated by repeated boluses of sodium nitrite and thiosulphate. The half-life of conversion of acetonitrile was 40 hours and harmful blood cyanide levels persisted for over 24 hours after ingestion. Departments treating or advising in cases of poisoning need to be aware of the delayed toxicity of acetonitrile. Monitoring in an intensive care unit of cases of acetonitrile poisoning should continue for 24-48 hours. PMID:9196706

  3. Delayed Diagnosis of Adult Indolent Systemic Mastocytosis

    PubMed Central

    Mikkelsen, Carsten Sauer; Nybo, Andrew; Arvesen, Kristian Bakke; Holk-Poulsen, Johan

    2014-01-01

    Systemic mastocytosis (SM) is a rare, heterogeneous disorder characterized by infiltration and accumulation of mast cells within multiple organs, most commonly the skin. Given the rarity of the disease and the fact that many of its symptoms are shared by more common disorders, a diagnosis may be delayed or hindered. These patients have an elevated risk of developing potentially life-threatening anaphylactoid reactions, thus underscoring the importance of keeping SM in mind as a differential diagnosis when a patient presents with chronic, itchy skin lesions and a history of multiple allergic reactions to bites, drugs, and anesthesia. We present a case illustrating that features of SM common to many disorders may hinder or delay its diagnosis. PMID:25386326

  4. Management of delayed posttraumatic cervical kyphosis.

    PubMed

    Lopez, Alejandro J; Scheer, Justin K; Abode-Iyamah, Kingsley; Smith, Zachary A; Hitchon, Patrick W; Dahdaleh, Nader S

    2016-01-01

    We describe three patients with misdiagnosed unstable fractures of the cervical spine, who were treated conservatively and developed kyphotic deformity, myelopathy, and radiculopathy. All three patients were then managed with closed reductions by crown halo traction, followed by instrumented fusions. Their neurologic function was regained without permanent disability in any patient. Unstable fractures of the cervical spine will progress to catastrophic neurologic injuries without surgical fixation. Posttraumatic kyphosis and the delayed reduction of partially healed fracture dislocations by preoperative traction are not well characterized in the subaxial cervical spine. The complete evaluation of any subaxial cervical spine fracture requires CT scanning to assess for bony fractures, and MRI to assess for ligamentous injury. This allows for assessment of the degree of instability and appropriate management. In patients with delayed posttraumatic cervical kyphosis, preoperative closed reduction provided adequate realignment, facilitating subsequent operative stabilization. PMID:26321304

  5. Delayed reactions to reusable protective gloves.

    PubMed

    Pontén, Ann; Dubnika, Inese

    2009-04-01

    The materials in plastic protective gloves are thought to cause less contact allergy than rubber gloves. Our aim was to estimate the frequency of delayed reactions to different types of reusable protective gloves among dermatitis patients. 2 x 2 cm pieces of polyvinyl chloride (PVC) gloves, nitrile gloves, and natural rubber latex (NRL) gloves were tested as is in consecutive dermatitis patients tested with the baseline series. Among 658 patients, 6 patients reacted to PVC gloves and 6 patients to the NRL gloves. None reacted to both these types of gloves. Five of six patients with reactions to rubber gloves reacted to thiuram mix in the baseline series. Delayed reactions to reusable PVC gloves may be as common as to reusable NRL gloves. In contrast to most reactions to the NRL glove, the reactions to the PVC glove had no obvious association with reactions to any allergen(s) in the baseline series. PMID:19338595

  6. Oscillations in SIRS model with distributed delays

    NASA Astrophysics Data System (ADS)

    Gonçalves, S.; Abramson, G.; Gomes, M. F. C.

    2011-06-01

    The ubiquity of oscillations in epidemics presents a long standing challenge for the formulation of epidemic models. Whether they are external and seasonally driven, or arise from the intrinsic dynamics is an open problem. It is known that fixed time delays destabilize the steady state solution of the standard SIRS model, giving rise to stable oscillations for certain parameters values. In this contribution, starting from the classical SIRS model, we make a general treatment of the recovery and loss of immunity terms. We present oscillation diagrams (amplitude and period) in terms of the parameters of the model, showing how oscillations can be destabilized by the shape of the distributions of the two characteristic (infectious and immune) times. The formulation is made in terms of delay equations which are both numerically integrated and linearized. Results from simulations are included showing where they support the linear analysis and explaining why not where they do not. Considerations and comparison with real diseases are presented along.

  7. Reconceptualizing Family Adaptation to Developmental Delay.

    PubMed

    Pedersen, Anita L; Crnic, Keith A; Baker, Bruce L; Blacher, Jan

    2015-07-01

    This study explores accurate conceptualization of the adaptation construct in families of children with developmental delay aged 3 to 8 years. Parents' self-reported measures of adaptation and observed dyadic relationship variables were examined. Confirmatory factor analysis and longitudinal growth modeling were used to evaluate the nature of adaptational processes. Results indicate that adaptational processes vary across adaptation index, child developmental level, and parent gender. Adaptation indices did not load onto a single construct at any time point. Several adaptational processes remained stable across time, although others showed linear or quadratic change. The findings of the current study indicate that it is time for a change in how adaptation is conceived for families of children with developmental delay. PMID:26161471

  8. Flow-induced delayed Freedericksz transition

    NASA Astrophysics Data System (ADS)

    Mottram, N. J.; McKay, G.; Brown, C. V.; Russell, C. T.; Sage, I. C.; Tsakonas, C.

    2016-03-01

    We demonstrate that a compact manometer experiment allows direct observation of a delay to the classical electric-field-induced Freedericksz transition produced by flow in a highly dispersive nematic liquid crystal layer. The Ericksen-Leslie equations are used to show that a flow aligning torque generated in the nematic layer under Poiseuille flow competes with the orthogonal electric-field reorientation torque. This model fully reproduces the experimental results using only self-consistently determined viscosity values, and predicts a more generally applicable expression for the dependence of the delay Ec∝√{ζ /Δ χe } on the shear rate ζ and on the electric susceptibility anisotropy Δ χe .

  9. Time delay measurement in the frequency domain

    DOE PAGESBeta

    Durbin, Stephen M.; Liu, Shih -Chieh; Dufresne, Eric M.; Li, Yuelin; Wen, Haidan

    2015-08-06

    Pump–probe studies at synchrotrons using X-ray and laser pulses require accurate determination of the time delay between pulses. This becomes especially important when observing ultrafast responses with lifetimes approaching or even less than the X-ray pulse duration (~100 ps). The standard approach of inspecting the time response of a detector sensitive to both types of pulses can have limitations due to dissimilar pulse profiles and other experimental factors. Here, a simple alternative is presented, where the frequency response of the detector is monitored versus time delay. Measurements readily demonstrate a time resolution of ~1 ps. Improved precision is possible bymore » simply extending the data acquisition time.« less

  10. Time delay measurement in the frequency domain

    SciTech Connect

    Durbin, Stephen M.; Liu, Shih -Chieh; Dufresne, Eric M.; Li, Yuelin; Wen, Haidan

    2015-08-06

    Pump–probe studies at synchrotrons using X-ray and laser pulses require accurate determination of the time delay between pulses. This becomes especially important when observing ultrafast responses with lifetimes approaching or even less than the X-ray pulse duration (~100 ps). The standard approach of inspecting the time response of a detector sensitive to both types of pulses can have limitations due to dissimilar pulse profiles and other experimental factors. Here, a simple alternative is presented, where the frequency response of the detector is monitored versus time delay. Measurements readily demonstrate a time resolution of ~1 ps. Improved precision is possible by simply extending the data acquisition time.

  11. Neutron fluctuations: The importance of being delayed

    NASA Astrophysics Data System (ADS)

    Houchmandzadeh, B.; Dumonteil, E.; Mazzolo, A.; Zoia, A.

    2015-11-01

    The neutron population in a nuclear reactor is subject to fluctuations in time and in space due to the competition of diffusion by scattering, births by fission events, and deaths by absorptions. As such, fission chains provide a prototype model for the study of spatial clustering phenomena. In order for the reactor to be operated in stationary conditions at the critical point, the population of prompt neutrons instantaneously emitted at fission must be in equilibrium with the much smaller population of delayed neutrons, emitted after a Poissonian time by nuclear decay of the fissioned nuclei. In this work, we will show that the delayed neutrons, although representing a tiny fraction of the total number of neutrons in the reactor, actually have a key impact on the fluctuations, and their contribution is very effective in quenching the spatial clustering.

  12. Neutron fluctuations: The importance of being delayed.

    PubMed

    Houchmandzadeh, B; Dumonteil, E; Mazzolo, A; Zoia, A

    2015-11-01

    The neutron population in a nuclear reactor is subject to fluctuations in time and in space due to the competition of diffusion by scattering, births by fission events, and deaths by absorptions. As such, fission chains provide a prototype model for the study of spatial clustering phenomena. In order for the reactor to be operated in stationary conditions at the critical point, the population of prompt neutrons instantaneously emitted at fission must be in equilibrium with the much smaller population of delayed neutrons, emitted after a Poissonian time by nuclear decay of the fissioned nuclei. In this work, we will show that the delayed neutrons, although representing a tiny fraction of the total number of neutrons in the reactor, actually have a key impact on the fluctuations, and their contribution is very effective in quenching the spatial clustering. PMID:26651654

  13. A hypothesis for delayed dynamic earthquake triggering

    USGS Publications Warehouse

    Parsons, T.

    2005-01-01

    It's uncertain whether more near-field earthquakes are triggered by static or dynamic stress changes. This ratio matters because static earthquake interactions are increasingly incorporated into probabilistic forecasts. Recent studies were unable to demonstrate all predictions from the static-stress-change hypothesis, particularly seismicity rate reductions. However, current dynamic stress change hypotheses do not explain delayed earthquake triggering and Omori's law. Here I show numerically that if seismic waves can alter some frictional contacts in neighboring fault zones, then dynamic triggering might cause delayed triggering and an Omori-law response. The hypothesis depends on faults following a rate/state friction law, and on seismic waves changing the mean critical slip distance (Dc) at nucleation zones.

  14. Inertia, gravitation, and radiation time delays

    SciTech Connect

    Graneau, P.

    1987-05-01

    This note explains how an instantaneous action-at-a-distance theory gives rise to time delays between a cause in one location and its effect at another. The key to this is a suitable law of induction which itself does not produce the time delay, but contains the cause in the form of a time derivative. The many-body solution process for an array of simultaneous induction equations then reveals retardation between cause and effect without the transport of energy at finite velocity. It is suggested that a suitable law of induction of inertia applied to an object in the solar system and the many-body universe may furnish the quantitative connection between inertia and Newtonian gravitation.

  15. Titrating-delay matching-to-sample in the pigeon.

    PubMed

    Kangas, Brian D; Vaidya, Manish; Branch, Marc N

    2010-07-01

    The titrating-delay matching-to-sample (TDMTS) procedure offers researchers an additional behavioral task thought to capture some important features of remembering. In this procedure, the delay between sample offset and comparison onset adjusts as a function of the subject's performance. Specifically, correct matches increase the delay and incorrect matches decrease the delay, and steady-state titrated delays serve as the primary dependent measure. The present series of experiments investigated the effects of several procedural variables on performance in TDMTS procedures in an effort to elucidate better its features to allow for more precision in future use. Experiment 1 reports results from a parametric analysis of fixed-ratio response requirements on the sample key that indicated improved remembering in the form of higher daily titrated delay values as the requirement was increased. Experiment 2 investigated the extent to which the initial delay value in each session affected session-wide delay values. Results indicated that regardless of value of the initial delay, the subjects' performances adjusted the delay values in the direction of the known baseline delay-value levels. Experiment 3 manipulated the step size by which delay values were adjusted and the results indicated that larger step sizes increased both session-to-session variability and within-session range of titrated delay values, although the average values remained approximately the same. These results suggest that the TDMTS task serves as a promising procedure to study what many refer to as memory. PMID:21279163

  16. On routing algorithms with end-to-end delay guarantees

    SciTech Connect

    Rao, N.S.V.; Batsell, S.G.

    1998-11-01

    The authors consider the transmission of a message of size r from a source to a destination with guarantees on the end-to-end delay over a computer network with n nodes and m links. There are three sources of delays: (a) propagation delays along the links, (b) delays due to bandwidth availability on the links, and (c) queuing delays at the intermediate nodes. First, the authors consider that delays on various links and nodes are given as functions of the message size. If the delay in (b) is a non-increasing function of the bandwidth, they propose O(m{sup 2} + mn log n) time algorithm to compute a path with the minimum end-to-end delay for any given message size r. They then consider that the queuing delay in (c) is a random variable correlated with the message size according to an unknown distribution. At each node, the measurements of queuing delays and message sizes are available. They propose two algorithms to compute paths whose delays are close to optimal delays with a high probability, irrespective of the distribution of the delays, and based entirely on the measurements of sufficient size.

  17. Modeling mechanisms of persisting and resolving delay in language development.

    PubMed

    Thomas, Michael S C; Knowland, V C P

    2014-04-01

    PURPOSE In this study, the authors used neural network modeling to investigate the possible mechanistic basis of developmental language delay and to test the viability of the hypothesis that persisting delay and resolving delay lie on a mechanistic continuum with normal development. METHOD The authors used a population modeling approach to study individual rates of development in 1,000 simulated individuals acquiring a notional language domain (in this study, represented by English past tense). Variation was caused by differences in internal neurocomputational learning parameters as well as the richness of the language environment. An early language delay group was diagnosed, and individual trajectories were then traced. RESULTS Quantitative variations in learning mechanisms were sufficient to produce persisting delay and resolving delay subgroups in similar proportions to empirical observations. In the model, persisting language delay was caused by limitations in processing capacity, whereas resolving delay was caused by low plasticity. Richness of the language environment did not predict the emergence of persisting delay but did predict the final ability levels of individuals with resolving delay. CONCLUSION Mechanistically, it is viable that persisting delay and resolving delay are only quantitatively different. There may be an interaction between environmental factors and outcome groups, with individuals who have resolving delay being influenced more by the richness of the language environment. PMID:24129016

  18. Delayed commutation in quantum computer networks.

    PubMed

    García-Escartín, Juan Carlos; Chamorro-Posada, Pedro

    2006-09-15

    In the same way that classical computer networks connect and enhance the capabilities of classical computers, quantum networks can combine the advantages of quantum information and communication. We propose a nonclassical network element, a delayed commutation switch, that can solve the problem of switching time in packet switching networks. With the help of some local ancillary qubits and superdense codes, we can route a qubit packet after part of it has left the network node. PMID:17025870

  19. Delay in ambulance dispatch to road accidents.

    PubMed

    Brodsky, H

    1992-06-01

    When a road accident occurs, the police communications officer, or 911 operator, generally receives the first call. If the caller reports injuries, the emergency medical services dispatcher is notified immediately; but if the caller is uncertain of injuries, the operator may wait. Most often an ambulance is not needed. However, in nearly 20% of fatal road accidents in Missouri, waiting for confirmation of need resulted in a delay of 5 minutes or more in the dispatch of an ambulance. PMID:1585968

  20. Delay in ambulance dispatch to road accidents.

    PubMed Central

    Brodsky, H

    1992-01-01

    When a road accident occurs, the police communications officer, or 911 operator, generally receives the first call. If the caller reports injuries, the emergency medical services dispatcher is notified immediately; but if the caller is uncertain of injuries, the operator may wait. Most often an ambulance is not needed. However, in nearly 20% of fatal road accidents in Missouri, waiting for confirmation of need resulted in a delay of 5 minutes or more in the dispatch of an ambulance. PMID:1585968

  1. Delayed psychiatric sequelae among Falklands war veterans

    PubMed Central

    Jones, Gareth H.; Lovett, Jonathan W.T.

    1987-01-01

    The only published account to date of psychiatric complications among Falklands war veterans suggests that acute reactions are rare. Reported here are three cases of severe delayed reactions in Falklands veterans from South Wales. All three cases demonstrate a common pattern similar to that shown by Vietnam war veterans. Possible aetiological factors and prevention are discussed. It seems likely that relatives of combatants will also be affected and general practitioners are in a unique position to recognize and treat these problems. PMID:3668924

  2. Delayed homicides and the proximate cause.

    PubMed

    Lin, Peter; Gill, James R

    2009-12-01

    Delayed homicides result from complications of remote injuries inflicted by "the hands of another." The investigation of delayed homicides may be a challenge due to a number of factors including: failure to report the death to the proper authorities, lack of ready and adequate documentation of the original injury and circumstances, and jurisdictional differences between the places of injury and death. The certification of these deaths also requires the demonstration of a pathophysiologic link between the remote injury and death. In sorting through these issues, it is helpful to rely upon the definition of the proximate cause of death. Over a 2-year period in New York City, there were 1211 deaths certified as homicide of which 42 were due to injuries sustained greater than 1 year before death. The survival interval ranged from 1.3 to 43.2 years. The most common immediate causes of death were: infections (22), seizures (7), and intestinal obstructions/hernias (6). Common patterns of complications included infection following a gunshot wound of the spinal cord, seizure disorder due to blunt head trauma, and intestinal obstruction/hernia due to adhesions from an abdominal stab wound. Spinal cord injuries resulted in paraplegia in 14 instances and quadriplegia in 8. The mean survival interval for paraplegics was 20.3 years and 14.8 years for quadriplegics; infections were a frequent immediate cause of death in both groups, particularly infections due to chronic bladder catheterization. The definition of proximate cause originated with civil law cases and was later applied to death certification as the proximate cause of death. The gradual extinction of the "year and a day rule" for the limitation of bringing homicide charges in delayed deaths may result in more of these deaths going to trial. Medical examiners/coroners must be able to explain the reasoning behind these death certifications and maintain consistent standards for the certification of all delayed deaths due

  3. Delayed Sleep Phase Disorder In Temporal Isolation

    PubMed Central

    Campbell, Scott S.; Murphy, Patricia J.

    2007-01-01

    Study Objectives: This study sought to characterize sleep and the circadian rhythm of body core temperature of an individual with delayed sleep phase disorder (DSPD) in the absence of temporal cues and social entrainment and to compare those measures to age-matched normal control subjects studied under identical conditions. Design: Polysomnography and body temperature were recorded continuously for 4 days in entrained conditions, followed immediately by 17 days in a “free-running” environment. Setting: Temporal isolation facility in the Laboratory of Human Chronobiology, Weill Cornell Medical College. Participants: One individual who met criteria for delayed sleep phase disorder according to the International Classification of Sleep Disorders Diagnostic and Coding Manual (ICSD-2) and 3 age-matched control subjects. Interventions: None. Measurements and Results: The DSPD subject had a spontaneous period length (tau) of 25.38 hours compared to an average tau of 24.44 hours for the healthy controls. The DSPD subject also showed an altered phase relationship between sleep/wake and body temperature rhythms, as well as longer sleep latency, poorer sleep efficiency, and altered distribution of slow wave sleep (SWS) within sleep episodes, compared to control subjects. Conclusions: Delayed sleep phase disorder may be the reflection of an abnormal circadian timing system characterized not only by a long tau, but also by an altered internal phase relationship between the sleep/wake system and the circadian rhythm of body temperature. The latter results in significantly disturbed sleep, even when DSPD patients are permitted to sleep and wake at their preferred times. Citation: Campbell SS; Murphy PJ. Delayed sleep phase disorder in temporal isolation. SLEEP 2007;30(9):1225-1228. PMID:17910395

  4. Tunneling Time and Weak Measurement in Strong Field Ionization

    NASA Astrophysics Data System (ADS)

    Zimmermann, Tomáš; Mishra, Siddhartha; Doran, Brent R.; Gordon, Daniel F.; Landsman, Alexandra S.

    2016-06-01

    Tunneling delays represent a hotly debated topic, with many conflicting definitions and little consensus on when and if such definitions accurately describe the physical observables. Here, we relate these different definitions to distinct experimental observables in strong field ionization, finding that two definitions, Larmor time and Bohmian time, are compatible with the attoclock observable and the resonance lifetime of a bound state, respectively. Both of these definitions are closely connected to the theory of weak measurement, with Larmor time being the weak measurement value of tunneling time and Bohmian trajectory corresponding to the average particle trajectory, which has been recently reconstructed using weak measurement in a two-slit experiment [S. Kocsis, B. Braverman, S. Ravets, M. J. Stevens, R. P. Mirin, L. K. Shalm, and A. M. Steinberg, Science 332, 1170 (2011)]. We demonstrate a big discrepancy in strong field ionization between the Bohmian and weak measurement values of tunneling time, and we suggest this arises because the tunneling time is calculated for a small probability postselected ensemble of electrons. Our results have important implications for the interpretation of experiments in attosecond science, suggesting that tunneling is unlikely to be an instantaneous process.

  5. Tunneling Time and Weak Measurement in Strong Field Ionization.

    PubMed

    Zimmermann, Tomáš; Mishra, Siddhartha; Doran, Brent R; Gordon, Daniel F; Landsman, Alexandra S

    2016-06-10

    Tunneling delays represent a hotly debated topic, with many conflicting definitions and little consensus on when and if such definitions accurately describe the physical observables. Here, we relate these different definitions to distinct experimental observables in strong field ionization, finding that two definitions, Larmor time and Bohmian time, are compatible with the attoclock observable and the resonance lifetime of a bound state, respectively. Both of these definitions are closely connected to the theory of weak measurement, with Larmor time being the weak measurement value of tunneling time and Bohmian trajectory corresponding to the average particle trajectory, which has been recently reconstructed using weak measurement in a two-slit experiment [S. Kocsis, B. Braverman, S. Ravets, M. J. Stevens, R. P. Mirin, L. K. Shalm, and A. M. Steinberg, Science 332, 1170 (2011)]. We demonstrate a big discrepancy in strong field ionization between the Bohmian and weak measurement values of tunneling time, and we suggest this arises because the tunneling time is calculated for a small probability postselected ensemble of electrons. Our results have important implications for the interpretation of experiments in attosecond science, suggesting that tunneling is unlikely to be an instantaneous process. PMID:27341232

  6. Coherent Dynamics Following Strong Field Ionization of Polyatomic Molecules

    NASA Astrophysics Data System (ADS)

    Konar, Arkaprabha; Shu, Yinan; Lozovoy, Vadim; Jackson, James; Levine, Benjamin; Dantus, Marcos

    2015-03-01

    Molecules, as opposed to atoms, present confounding possibilities of nuclear and electronic motion upon strong field ionization. The dynamics and fragmentation patterns in response to the laser field are structure sensitive; therefore, a molecule cannot simply be treated as a ``bag of atoms'' during field induced ionization. We consider here to what extent molecules retain their molecular identity and properties under strong laser fields. Using time-of-flight mass spectrometry in conjunction with pump-probe techniques we study the dynamical behavior of these molecules, monitoring ion yield modulation caused by intramolecular motions post ionization. The delay scans show that among positional isomers the variations in relative energies, amounting to only a few hundred meVs, influence the dynamical behavior of the molecules despite their having experienced such high fields (V/Å). Ab initio calculations were performed to predict dynamics along with single and multiphoton resonances in the neutral and ionic states. We propose that single electron ionization occurs within an optical cycle with the electron carrying away essentially all of the energy, leaving behind little internal energy in the cation. Evidence for this observation comes from coherent vibrational motion governed by the potential energy surface of the ground state of the cation. Subsequent fragmentation of the cation takes place as a result of further photon absorption modulated by one- and two-photon resonances, which provide sufficient energy to overcome the dissociation energy.

  7. Exponential Synchronization of Coupled Stochastic Memristor-Based Neural Networks With Time-Varying Probabilistic Delay Coupling and Impulsive Delay.

    PubMed

    Bao, Haibo; Park, Ju H; Cao, Jinde

    2016-01-01

    This paper deals with the exponential synchronization of coupled stochastic memristor-based neural networks with probabilistic time-varying delay coupling and time-varying impulsive delay. There is one probabilistic transmittal delay in the delayed coupling that is translated by a Bernoulli stochastic variable satisfying a conditional probability distribution. The disturbance is described by a Wiener process. Based on Lyapunov functions, Halanay inequality, and linear matrix inequalities, sufficient conditions that depend on the probability distribution of the delay coupling and the impulsive delay were obtained. Numerical simulations are used to show the effectiveness of the theoretical results. PMID:26485723

  8. β-delayed neutron emission studies

    NASA Astrophysics Data System (ADS)

    Gómez-Hornillos, M. B.; Rissanen, J.; Taín, J. L.; Algora, A.; Kratz, K. L.; Lhersonneau, G.; Pfeiffer, B.; Agramunt, J.; Cano-Ott, D.; Gorlychev, V.; Caballero-Folch, R.; Martínez, T.; Achouri, L.; Calvino, F.; Cortés, G.; Eronen, T.; García, A.; Parlog, M.; Podolyak, Z.; Pretel, C.; Valencia, E.

    2014-01-01

    The study of β-delayed neutron emission plays a major role in different fields such as nuclear technology, nuclear astrophysics and nuclear structure. However the quality of the existing experimental data nowadays is not sufficient for the various technical and scientific applications and new high precision measurements are necessary to improve the data bases. One key aspect to the success of these high precission measurements is the use of a very pure ion beam that ensures that only the ion of interest is produced. The combination of the IGISOL mass separator with the JYFLTRAP Penning trap is an excellent tool for this type of measurement because of the ability to deliver isobarically and even isomerically clean beams. Another key feature of the installation is the non-chemical selectivity of the IGISOL ion source which allows measurements in the important region of refractory elements. This paper summarises the β-delayed neutron emission studies that have been carried out at the IGISOL facility with two different neutron detectors based on 3He counters in a polyethylene moderator: the Mainz neutron detector and the BEta deLayEd Neutron detector.

  9. Microwave photonic delay line signal processing.

    PubMed

    Diehl, John F; Singley, Joseph M; Sunderman, Christopher E; Urick, Vincent J

    2015-11-01

    This paper provides a path for the design of state-of-the-art fiber-optic delay lines for signal processing. The theoretical forms for various radio-frequency system performance metrics are derived for four modulation types: X- and Z-cut Mach-Zehnder modulators, a phase modulator with asymmetric Mach-Zehnder interferometer, and a polarization modulator with control waveplate and polarizing beam splitter. Each modulation type is considered to cover the current and future needs for ideal system designs. System gain, compression point, and third-order output intercept point are derived from the transfer matrices for each modulation type. A discussion of optical amplifier placement and fiber-effect mitigation is offered. The paper concludes by detailing two high-performance delay lines, built for unique applications, that exhibit performance levels an order of magnitude better than commercial delay lines. This paper should serve as a guide to maximizing the performance of future systems and offer a look into current and future research being done to further improve photonics technologies. PMID:26560620

  10. Learning problems, delayed perceptual development, and puberty

    NASA Astrophysics Data System (ADS)

    Wright, Beverly A.; Zecker, Steven G.; Reid, Miriam D.

    2003-04-01

    Language-based learning problems affect approximately one person in twelve with no other obvious signs of disorder. Many of these individuals have accompanying deficits in nonlinguistic perception. To determine whether age influences the magnitude of these deficits, thresholds on a set of auditory masking tasks were measured in individuals with learning problems and controls ranging in age from 6 years to adult. Performance improved with increasing age in both groups. However, the thresholds of the individuals with learning problems were most similar to those of controls approximately 2-4 years younger on every task, suggesting that the perceptual development of the affected individuals was delayed by a constant amount. Further, on the subset of conditions on which controls reached adult levels of performance after 10 years of age, the improvement of affected individuals halted at 10 years of age, suggesting that puberty may play a critical role in human perceptual development. Taken together, these data support the idea that some learning problems result from a neuromaturational delay, of unknown breadth, and indicate that neurological changes associated with puberty prevent the complete resolution of delayed perceptual development. [Work supported by NIH/NIDCD.

  11. PROMPT Ia SUPERNOVAE ARE SIGNIFICANTLY DELAYED

    SciTech Connect

    Raskin, Cody; Scannapieco, Evan; Rhoads, James; Della Valle, Massimo

    2009-12-10

    The time delay between the formation of a population of stars and the onset of type Ia supernovae (SNe Ia) sets important limits on the masses and nature of SN Ia progenitors. Here, we use a new observational technique to measure this time delay by comparing the spatial distributions of SNe Ia to their local environments. Previous work attempted such analyses encompassing the entire host of each SN Ia, yielding inconclusive results. Our approach confines the analysis only to the relevant portions of the hosts, allowing us to show that even so-called prompt SNe Ia that trace star formation on cosmic timescales exhibit a significant delay time of 200-500 million years. This implies that either the majority of Ia companion stars have main-sequence masses less than 3 M {sub sun}, or that most SNe Ia arise from double white dwarf binaries. Our results are also consistent with a SNe Ia rate that traces the white dwarf formation rate, scaled by a fixed efficiency factor.

  12. Integrated Planning for Telepresence with Time Delays

    NASA Technical Reports Server (NTRS)

    Johnston, Mark D.; Rabe, Kenneth J.

    2006-01-01

    Teleoperation of remote robotic systems over time delays in the range of 2-10 seconds poses a unique set of challenges. In the context of a supervisory control system for the JSC Robonaut humanoid robot, we have developed an 'intelligent assistant' that integrates an Artificial Intelligence planner (JSHOP2) with execution monitoring of the state of both the human supervisor and the remote robot. The assistant reasons simultaneously about the world state on both sides of the time delay, which represents a novel application of this technology. The purpose of the assistant is to provide advice to the human supervisor about current and future activities, derived from a sequence of high-level goals to be achieved. To do this, the assistant must simultaneously monitor and react to various data sources, including actions taken by the supervisor who is issuing commands to the robot (e.g. with a data glove), actions taken by the robot, and the environment of the robot, both as currently perceived over the time delay, along with the current sequence of goals. We have developed a 'leader/follower' software architecture to handle the dual time-shifted streams of execution feedback. In this paper we describe the integrated planner and its executive, and how it operates in normal and anomaly situations.

  13. Delayed Sleep Phase Disorder in Youth

    PubMed Central

    Gradisar, Michael; Crowley, Stephanie J.

    2014-01-01

    Purpose of review For over 30 years, Delayed Sleep Phase Disorder (DSPD) has been defined as a debilitating sleep condition. Recently there is more awareness of DSPD in young people, yet considerable information is needed to understand its etiology and treatment. This review describes the latest research findings describing the clinical features, etiology and treatment of DSPD. Recent findings The prevalence of DSPD in adolescents and young adults ranges from 1 to 16%. The impact on the individual is significant, particularly in the domains of school/work performance and mental health. We propose contributing factors include reduced homeostatic sleep pressure, a lengthened and delayed circadian rhythm, insensitivity to clock-resetting morning light, and heightened cognitive activity. Evening melatonin administration as a sole treatment appears promising, as is a combination of cognitive-behavior therapy plus morning bright light. Summary Recent findings suggest clinicians should be aware of the clinical features (i.e., significant daytime sleepiness, anxiety and depression symptoms, potential for school drop out) of DSPD, as several biological features underpinning this disorder are unseen in clinical settings. We advise clinicians to become familiar with exogenous evening melatonin administration, and cognitive and behavioral techniques to simultaneously treat the delayed circadian rhythm and associated sleep-onset insomnia. PMID:24060912

  14. Estimating magnitude and duration of incident delays

    SciTech Connect

    Garib, A.; Radwan, A.E.; Al-Deek, H.

    1997-11-01

    Traffic congestion is a major operational problem on urban freeways. In the case of recurring congestion, travelers can plan their trips according to the expected occurrence and severity of recurring congestion. However, nonrecurring congestion cannot be managed without real-time prediction. Evaluating the efficiency of intelligent transportation systems (ITS) technologies in reducing incident effects requires developing models that can accurately predict incident duration along with the magnitude of nonrecurring congestion. This paper provides two statistical models for estimating incident delay and a model for predicting incident duration. The incident delay models showed that up to 85% of variation in incident delay can be explained by incident duration, number of lanes affected, number of vehicles involved, and traffic demand before the incident. The incident duration prediction model showed that 81% of variation in incident duration can be predicted by number of lanes affected, number of vehicles involved, truck involvement, time of day, police response time, and weather condition. These findings have implications for on-line applications within the context of advanced traveler information systems (ATIS).

  15. The etiology of delayed sleep phase disorder.

    PubMed

    Micic, Gorica; Lovato, Nicole; Gradisar, Michael; Ferguson, Sally A; Burgess, Helen J; Lack, Leon C

    2016-06-01

    According to classification manuals for sleep disorders, nine disorders are directly related to biological clock timing misalignments. Of all, delayed sleep phase disorder (DSPD) is the most commonly diagnosed, predominantly affecting adolescents, young adults, and insomnia patients. It is a persistent inability to fall asleep at earlier, more desirable and socially conventional times, coupled with extreme difficulty awakening in the morning. Considerable evidence shows a delay in the circadian clock to be associated with DSPD. Therefore, treatments have mainly focused on advancing the biological clock and sleep timing through pharmacotherapy, phototherapy and behavioral therapies. The clinical evidence indicates that these treatments are efficacious, at least in the short term. However, follow up studies show frequent patient relapse, leading researchers to speculate that alternative etiologies may be contributing to sleep and circadian clock delays in DSPD. The aim of the present paper is to review and collate current literature related to DSPD etiology in order to outline gaps in current knowledge and suggest future research. PMID:26434674

  16. 40 CFR 60.692-7 - Standards: Delay of compliance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Emissions From Petroleum Refinery Wastewater Systems § 60.692-7 Standards: Delay of compliance. (a) Delay of compliance of modified individual drain systems with ancillary downstream treatment components will...

  17. Couples Living in Zika Areas Should Delay Pregnancy, WHO Advises

    MedlinePlus

    ... medlineplus/news/fullstory_159310.html Couples Living in Zika Areas Should Delay Pregnancy, WHO Advises Agency acknowledges ... are trying to have children and live in Zika-affected areas should consider delaying pregnancy to avoid ...

  18. Genetic Insights May Help Kids Battling Developmental Delays

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_159026.html Genetic Insights May Help Kids Battling Developmental Delays DNA ... delays, with a new study showing that extensive genetic analysis may help determine the cause of their ...

  19. Genetic Insights May Help Kids Battling Developmental Delays

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_159026.html Genetic Insights May Help Kids Battling Developmental Delays DNA ... delays, with a new study showing that extensive genetic analysis may help determine the cause of their ...

  20. Couples Living in Zika Areas Should Delay Pregnancy, WHO Advises

    MedlinePlus

    ... gov/news/fullstory_159310.html Couples Living in Zika Areas Should Delay Pregnancy, WHO Advises Agency acknowledges ... are trying to have children and live in Zika-affected areas should consider delaying pregnancy to avoid ...