NASA Astrophysics Data System (ADS)
Miksovsky, J.; Raidl, A.
Time delays phase space reconstruction represents one of useful tools of nonlinear time series analysis, enabling number of applications. Its utilization requires the value of time delay to be known, as well as the value of embedding dimension. There are sev- eral methods how to estimate both these parameters. Typically, time delay is computed first, followed by embedding dimension. Our presented approach is slightly different - we reconstructed phase space for various combinations of mentioned parameters and used it for prediction by means of the nearest neighbours in the phase space. Then some measure of prediction's success was computed (correlation or RMSE, e.g.). The position of its global maximum (minimum) should indicate the suitable combination of time delay and embedding dimension. Several meteorological (particularly clima- tological) time series were used for the computations. We have also created a MS- Windows based program in order to implement this approach - its basic features will be presented as well.
Evidence for chaos in an experimental time series from serrated plastic flow
NASA Astrophysics Data System (ADS)
Venkadesan, S.; Valsakumar, M. C.; Murthy, K. P. N.; Rajasekar, S.
1996-07-01
An experimental time series from a tensile test of an Al-Mg alloy in the serrated plastic flow domain is analyzed for signature of chaos. We employ state space reconstruction by embedding of time delay vectors. The minimum embedding dimension is found to be 4 and the largest Lyapunov exponent is positive, thereby providing prima facie evidence for chaos in an experimental time series of serrated plastic flow data.
Cannistraci, Carlo Vittorio; Alanis-Lobato, Gregorio; Ravasi, Timothy
2013-01-01
Motivation: Most functions within the cell emerge thanks to protein–protein interactions (PPIs), yet experimental determination of PPIs is both expensive and time-consuming. PPI networks present significant levels of noise and incompleteness. Predicting interactions using only PPI-network topology (topological prediction) is difficult but essential when prior biological knowledge is absent or unreliable. Methods: Network embedding emphasizes the relations between network proteins embedded in a low-dimensional space, in which protein pairs that are closer to each other represent good candidate interactions. To achieve network denoising, which boosts prediction performance, we first applied minimum curvilinear embedding (MCE), and then adopted shortest path (SP) in the reduced space to assign likelihood scores to candidate interactions. Furthermore, we introduce (i) a new valid variation of MCE, named non-centred MCE (ncMCE); (ii) two automatic strategies for selecting the appropriate embedding dimension; and (iii) two new randomized procedures for evaluating predictions. Results: We compared our method against several unsupervised and supervisedly tuned embedding approaches and node neighbourhood techniques. Despite its computational simplicity, ncMCE-SP was the overall leader, outperforming the current methods in topological link prediction. Conclusion: Minimum curvilinearity is a valuable non-linear framework that we successfully applied to the embedding of protein networks for the unsupervised prediction of novel PPIs. The rationale for our approach is that biological and evolutionary information is imprinted in the non-linear patterns hidden behind the protein network topology, and can be exploited for predicting new protein links. The predicted PPIs represent good candidates for testing in high-throughput experiments or for exploitation in systems biology tools such as those used for network-based inference and prediction of disease-related functional modules. Availability: https://sites.google.com/site/carlovittoriocannistraci/home Contact: kalokagathos.agon@gmail.com or timothy.ravasi@kaust.edu.sa Supplementary information: Supplementary data are available at Bioinformatics online. PMID:23812985
Inflation from higher dimensions
NASA Astrophysics Data System (ADS)
Nakada, Hiroshi; Ketov, Sergei V.
2017-12-01
We derive the scalar potential in four spacetime dimensions from an eight-dimensional (R +γ R4-2 Λ -F42) gravity model in the presence of the 4-form F4, with the (modified gravity) coupling constant γ and the cosmological constant Λ , by using the flux compactification of four extra dimensions on a 4-sphere with the warp factor. The scalar potential depends upon two scalar fields: the scalaron and the 4-sphere volume modulus. We demonstrate that it gives rise to a viable description of cosmological inflation in the early universe, with the scalaron playing the role of inflaton and the volume modulus to be (almost) stabilized at its minimum. We also speculate about a possibility of embedding our model in eight dimensions into a modified eight-dimensional supergavity that, in its turn, arises from a modified eleven-dimensional supergravity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, J.H.; Ellis, J.R.; Montague, S.
1997-03-01
One of the principal applications of monolithically integrated micromechanical/microelectronic systems has been accelerometers for automotive applications. As integrated MEMS/CMOS technologies such as those developed by U.C. Berkeley, Analog Devices, and Sandia National Laboratories mature, additional systems for more sensitive inertial measurements will enter the commercial marketplace. In this paper, the authors will examine key technology design rules which impact the performance and cost of inertial measurement devices manufactured in integrated MEMS/CMOS technologies. These design parameters include: (1) minimum MEMS feature size, (2) minimum CMOS feature size, (3) maximum MEMS linear dimension, (4) number of mechanical MEMS layers, (5) MEMS/CMOS spacing.more » In particular, the embedded approach to integration developed at Sandia will be examined in the context of these technology features. Presently, this technology offers MEMS feature sizes as small as 1 {micro}m, CMOS critical dimensions of 1.25 {micro}m, MEMS linear dimensions of 1,000 {micro}m, a single mechanical level of polysilicon, and a 100 {micro}m space between MEMS and CMOS. This is applicable to modern precision guided munitions.« less
Change in the Embedding Dimension as an Indicator of an Approaching Transition
Neuman, Yair; Marwan, Norbert; Cohen, Yohai
2014-01-01
Predicting a transition point in behavioral data should take into account the complexity of the signal being influenced by contextual factors. In this paper, we propose to analyze changes in the embedding dimension as contextual information indicating a proceeding transitive point, called OPtimal Embedding tRANsition Detection (OPERAND). Three texts were processed and translated to time-series of emotional polarity. It was found that changes in the embedding dimension proceeded transition points in the data. These preliminary results encourage further research into changes in the embedding dimension as generic markers of an approaching transition point. PMID:24979691
Cannistraci, Carlo Vittorio; Ravasi, Timothy; Montevecchi, Franco Maria; Ideker, Trey; Alessio, Massimo
2010-09-15
Nonlinear small datasets, which are characterized by low numbers of samples and very high numbers of measures, occur frequently in computational biology, and pose problems in their investigation. Unsupervised hybrid-two-phase (H2P) procedures-specifically dimension reduction (DR), coupled with clustering-provide valuable assistance, not only for unsupervised data classification, but also for visualization of the patterns hidden in high-dimensional feature space. 'Minimum Curvilinearity' (MC) is a principle that-for small datasets-suggests the approximation of curvilinear sample distances in the feature space by pair-wise distances over their minimum spanning tree (MST), and thus avoids the introduction of any tuning parameter. MC is used to design two novel forms of nonlinear machine learning (NML): Minimum Curvilinear embedding (MCE) for DR, and Minimum Curvilinear affinity propagation (MCAP) for clustering. Compared with several other unsupervised and supervised algorithms, MCE and MCAP, whether individually or combined in H2P, overcome the limits of classical approaches. High performance was attained in the visualization and classification of: (i) pain patients (proteomic measurements) in peripheral neuropathy; (ii) human organ tissues (genomic transcription factor measurements) on the basis of their embryological origin. MC provides a valuable framework to estimate nonlinear distances in small datasets. Its extension to large datasets is prefigured for novel NMLs. Classification of neuropathic pain by proteomic profiles offers new insights for future molecular and systems biology characterization of pain. Improvements in tissue embryological classification refine results obtained in an earlier study, and suggest a possible reinterpretation of skin attribution as mesodermal. https://sites.google.com/site/carlovittoriocannistraci/home.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Dimensions Using All-Bar Cuts (Triangular Cuts); Large Frame TED Escape Opening; Minimum Dimensions Using All-Bar Cuts and Leading Edge Cut; Large Frame TED Escape Opening; Minimum Dimensions Using All-Points...—Large Frame TED Escape Opening; Minimum Dimensions Using All-Bar Cuts (Triangular Cuts); Large Frame TED...
Code of Federal Regulations, 2012 CFR
2012-10-01
... Dimensions Using All-Bar Cuts (Triangular Cuts); Large Frame TED Escape Opening; Minimum Dimensions Using All-Bar Cuts and Leading Edge Cut; Large Frame TED Escape Opening; Minimum Dimensions Using All-Points...—Large Frame TED Escape Opening; Minimum Dimensions Using All-Bar Cuts (Triangular Cuts); Large Frame TED...
Code of Federal Regulations, 2014 CFR
2014-10-01
... Dimensions Using All-Bar Cuts (Triangular Cuts); Large Frame TED Escape Opening; Minimum Dimensions Using All-Bar Cuts and Leading Edge Cut; Large Frame TED Escape Opening; Minimum Dimensions Using All-Points...—Large Frame TED Escape Opening; Minimum Dimensions Using All-Bar Cuts (Triangular Cuts); Large Frame TED...
Functional feature embedded space mapping of fMRI data.
Hu, Jin; Tian, Jie; Yang, Lei
2006-01-01
We have proposed a new method for fMRI data analysis which is called Functional Feature Embedded Space Mapping (FFESM). Our work mainly focuses on the experimental design with periodic stimuli which can be described by a number of Fourier coefficients in the frequency domain. A nonlinear dimension reduction technique Isomap is applied to the high dimensional features obtained from frequency domain of the fMRI data for the first time. Finally, the presence of activated time series is identified by the clustering method in which the information theoretic criterion of minimum description length (MDL) is used to estimate the number of clusters. The feasibility of our algorithm is demonstrated by real human experiments. Although we focus on analyzing periodic fMRI data, the approach can be extended to analyze non-periodic fMRI data (event-related fMRI) by replacing the Fourier analysis with a wavelet analysis.
Dimension from covariance matrices.
Carroll, T L; Byers, J M
2017-02-01
We describe a method to estimate embedding dimension from a time series. This method includes an estimate of the probability that the dimension estimate is valid. Such validity estimates are not common in algorithms for calculating the properties of dynamical systems. The algorithm described here compares the eigenvalues of covariance matrices created from an embedded signal to the eigenvalues for a covariance matrix of a Gaussian random process with the same dimension and number of points. A statistical test gives the probability that the eigenvalues for the embedded signal did not come from the Gaussian random process.
Dimension towers of SICs. I. Aligned SICs and embedded tight frames
NASA Astrophysics Data System (ADS)
Appleby, Marcus; Bengtsson, Ingemar; Dumitru, Irina; Flammia, Steven
2017-11-01
Algebraic number theory relates SIC-POVMs in dimension d > 3 to those in dimension d(d - 2). We define a SIC in dimension d(d - 2) to be aligned to a SIC in dimension d if and only if the squares of the overlap phases in dimension d appear as a subset of the overlap phases in dimension d(d - 2) in a specified way. We give 19 (mostly numerical) examples of aligned SICs. We conjecture that given any SIC in dimension d, there exists an aligned SIC in dimension d(d - 2). In all our examples, the aligned SIC has lower dimensional equiangular tight frames embedded in it. If d is odd so that a natural tensor product structure exists, we prove that the individual vectors in the aligned SIC have a very special entanglement structure, and the existence of the embedded tight frames follows as a theorem. If d - 2 is an odd prime number, we prove that a complete set of mutually unbiased bases can be obtained by reducing an aligned SIC to this dimension.
24 CFR 3280.110 - Minimum room dimensions.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Minimum room dimensions. The gross floor area required by § 3280.110 (a) and (b) shall have no clear horizontal dimension less than 5 feet except as permitted by § 3280.102(a). [40 FR 58752, Dec. 18, 1975... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Minimum room dimensions. 3280.110...
24 CFR 3280.110 - Minimum room dimensions.
Code of Federal Regulations, 2011 CFR
2011-04-01
... Minimum room dimensions. The gross floor area required by § 3280.110 (a) and (b) shall have no clear horizontal dimension less than 5 feet except as permitted by § 3280.102(a). [40 FR 58752, Dec. 18, 1975... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Minimum room dimensions. 3280.110...
24 CFR 3280.110 - Minimum room dimensions.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Minimum room dimensions. 3280.110... Minimum room dimensions. The gross floor area required by § 3280.110 (a) and (b) shall have no clear horizontal dimension less than 5 feet except as permitted by § 3280.102(a). [40 FR 58752, Dec. 18, 1975...
24 CFR 3280.110 - Minimum room dimensions.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Minimum room dimensions. 3280.110... Minimum room dimensions. The gross floor area required by § 3280.110 (a) and (b) shall have no clear horizontal dimension less than 5 feet except as permitted by § 3280.102(a). [40 FR 58752, Dec. 18, 1975...
24 CFR 3280.110 - Minimum room dimensions.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Minimum room dimensions. 3280.110... Minimum room dimensions. The gross floor area required by § 3280.110 (a) and (b) shall have no clear horizontal dimension less than 5 feet except as permitted by § 3280.102(a). [40 FR 58752, Dec. 18, 1975...
False-nearest-neighbors algorithm and noise-corrupted time series
NASA Astrophysics Data System (ADS)
Rhodes, Carl; Morari, Manfred
1997-05-01
The false-nearest-neighbors (FNN) algorithm was originally developed to determine the embedding dimension for autonomous time series. For noise-free computer-generated time series, the algorithm does a good job in predicting the embedding dimension. However, the problem of predicting the embedding dimension when the time-series data are corrupted by noise was not fully examined in the original studies of the FNN algorithm. Here it is shown that with large data sets, even small amounts of noise can lead to incorrect prediction of the embedding dimension. Surprisingly, as the length of the time series analyzed by FNN grows larger, the cause of incorrect prediction becomes more pronounced. An analysis of the effect of noise on the FNN algorithm and a solution for dealing with the effects of noise are given here. Some results on the theoretically correct choice of the FNN threshold are also presented.
Relations Between Embedded Figures Test Performance and Dimensions of the I-E Scale
ERIC Educational Resources Information Center
Strahan, Robert; Huth, Helga
1975-01-01
Relations between an embedded figures measure of field independence and various dimensions of Rotter's Internal-External Locus of Control Scale were investigated. The general absence of significant correlations suggests that these variables are essentially unrelated. (Author)
Embedding Dimension Selection for Adaptive Singular Spectrum Analysis of EEG Signal.
Xu, Shanzhi; Hu, Hai; Ji, Linhong; Wang, Peng
2018-02-26
The recorded electroencephalography (EEG) signal is often contaminated with different kinds of artifacts and noise. Singular spectrum analysis (SSA) is a powerful tool for extracting the brain rhythm from a noisy EEG signal. By analyzing the frequency characteristics of the reconstructed component (RC) and the change rate in the trace of the Toeplitz matrix, it is demonstrated that the embedding dimension is related to the frequency bandwidth of each reconstructed component, in consistence with the component mixing in the singular value decomposition step. A method for selecting the embedding dimension is thereby proposed and verified by simulated EEG signal based on the Markov Process Amplitude (MPA) EEG Model. Real EEG signal is also collected from the experimental subjects under both eyes-open and eyes-closed conditions. The experimental results show that based on the embedding dimension selection method, the alpha rhythm can be extracted from the real EEG signal by the adaptive SSA, which can be effectively utilized to distinguish between the eyes-open and eyes-closed states.
75 FR 18256 - Petition for Exemption; Summary of Petition Received
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-09
... an exemption from the specific dimensions of the passenger entry door of the Hawker Beechcraft Model 390-2. The door has basic dimensions greater than the minimum required by Sec. 23.783(f)(1). The total... than the minimum area required by Sec. 23.783(f)(1); however, the minimum width dimension cannot be met...
16 CFR 1512.19 - Instructions and labeling.
Code of Federal Regulations, 2012 CFR
2012-01-01
... assembly and adjustment, (2) a drawing illustrating the minimum leg-length dimension of a rider and a method of measurement of this dimension. (c) The minimum leg-length dimension shall be readily...
An Approach to Embedded Training for Future Leaders and Staff
2009-10-01
13. SUPPLEMENTARY NOTES See also ADA562526. RTO-MP-HFM-169 Human Dimensions in Embedded Virtual Simulation (Les dimensions humaines dans la...order to better capitalize on follow-on operations. 4.10 Theme 7: Sustain Unit Operations Theme 7 is defined as the ability of Soldiers and
Fractal dimension of spatially extended systems
NASA Astrophysics Data System (ADS)
Torcini, A.; Politi, A.; Puccioni, G. P.; D'Alessandro, G.
1991-10-01
Properties of the invariant measure are numerically investigated in 1D chains of diffusively coupled maps. The coarse-grained fractal dimension is carefully computed in various embedding spaces, observing an extremely slow convergence towards the asymptotic value. This is in contrast with previous simulations, where the analysis of an insufficient number of points led the authors to underestimate the increase of fractal dimension with increasing the dimension of the embedding space. Orthogonal decomposition is also performed confirming that the slow convergence is intrinsically related to local nonlinear properties of the invariant measure. Finally, the Kaplan-Yorke conjecture is tested for short chains, showing that, despite the noninvertibility of the dynamical system, a good agreement is found between Lyapunov dimension and information dimension.
Embedding of the brane into six dimensions
NASA Astrophysics Data System (ADS)
Gogberashvili, Merab
2002-10-01
Embedding of the brane metric into Euclidean (2+4)-space is found. Brane geometry can be visualized as the surface of the hypersphere in six dimensions which ``radius'' is governed by the cosmological constant. Minkowski space in this picture is placed on the intersection of this surface with the plane formed by the extra space-like and time-like coordinates.
Brenneman, Susan K; Shen, Wei; Brekke, Lee; Paczkowski, Rosirene; Bancroft, Tim; Kaplan, Sherrie H; Greenfield, Sheldon; Berger, Marc; Buesching, Don P
2014-09-01
To assess the ability of ENterprising SElective Multi-instrument BLend for hEterogeneity analysis (ENSEMBLE) Minimum Dataset instrument dimensions to discriminate among subgroups of patients expected to have differential outcomes. Patients with Type 2 diabetes, knee osteoarthritis, ischemic heart disease or heart failure completed a survey designed to represent three dimensions (health, personality and behavior). Health-related outcomes and utilization were investigated using claims data. Discriminant validity and associations between the dimensions and outcomes were assessed. A total of 2625 patients completed the survey. The dimensions discriminated 50-100% of the outcome levels across disease cohorts; behavior dimension scores did not differ significantly among the healthcare utilization level subgroups in any disease cohort. ENSEMBLE Minimum Dataset dimensions discriminated health-related outcome levels among patients with varied diseases.
Recurrence plot statistics and the effect of embedding
NASA Astrophysics Data System (ADS)
March, T. K.; Chapman, S. C.; Dendy, R. O.
2005-01-01
Recurrence plots provide a graphical representation of the recurrent patterns in a timeseries, the quantification of which is a relatively new field. Here we derive analytical expressions which relate the values of key statistics, notably determinism and entropy of line length distribution, to the correlation sum as a function of embedding dimension. These expressions are obtained by deriving the transformation which generates an embedded recurrence plot from an unembedded plot. A single unembedded recurrence plot thus provides the statistics of all possible embedded recurrence plots. If the correlation sum scales exponentially with embedding dimension, we show that these statistics are determined entirely by the exponent of the exponential. This explains the results of Iwanski and Bradley [J.S. Iwanski, E. Bradley, Recurrence plots of experimental data: to embed or not to embed? Chaos 8 (1998) 861-871] who found that certain recurrence plot statistics are apparently invariant to embedding dimension for certain low-dimensional systems. We also examine the relationship between the mutual information content of two timeseries and the common recurrent structure seen in their recurrence plots. This allows time-localized contributions to mutual information to be visualized. This technique is demonstrated using geomagnetic index data; we show that the AU and AL geomagnetic indices share half their information, and find the timescale on which mutual features appear.
An Examination of xMOOCs: An Embedded Single Case Study Based on Conole's 12 Dimensions
ERIC Educational Resources Information Center
Kocdar, Serpil; Okur, M. Recep; Bozkurt, Aras
2017-01-01
This study intends to examine the xMOOCs offered by one of the mainstream MOOC platforms in Conole's 12 dimensions. For this purpose, the research employed an embedded single case study using heuristic inquiry to collect data. The researchers participated in three xMOOCs and took into consideration the characteristics of these MOOCs by rating them…
29 CFR 1917.121 - Spiral stairways.
Code of Federal Regulations, 2010 CFR
2010-07-01
... minimum dimensions of Figure F-1; EC21OC91.020 Spiral Stairway—Minimum Dimensions A (half-tread width) B... 26.67 cm) in height; (3) Minimum loading capability shall be 100 pounds per square foot (4.79kN), and... least 6 feet, 6 inches (1.98 m) above the top step. (c) Maintenance. Spiral stairways shall be...
29 CFR 1917.121 - Spiral stairways.
Code of Federal Regulations, 2011 CFR
2011-07-01
... minimum dimensions of Figure F-1; EC21OC91.020 Spiral Stairway—Minimum Dimensions A (half-tread width) B... 26.67 cm) in height; (3) Minimum loading capability shall be 100 pounds per square foot (4.79kN), and... least 6 feet, 6 inches (1.98 m) above the top step. (c) Maintenance. Spiral stairways shall be...
Cross-cultural comparison of political leaders' operational codes.
Dirilen-Gumus, Ozlem
2017-12-01
This study aims at comparing operational codes (namely, philosophical and instrumental beliefs about the political universe) of political leaders from different cultures. According to Schwartz (2004), cultures can be categorised into 3 dimensions: autonomy-embeddedness, egalitarianism-hierarchy and mastery-harmony. This study draws upon the 1st dimension (akin to the most popular cultural dimension of Hofstede: individualism-collectivism) and focuses on comparing the leaders of autonomous and embedded cultures based on how cooperative/conflictual they are. The main research hypothesis is as follows: the leaders of embedded cultures would be more cooperative than the leaders of autonomous cultures. For this purpose, 3 autonomous cultures (the UK, Canada and Australia) and embedded cultures (Singapore, South Africa and Malaysia) cultures were chosen randomly and the cooperativeness of the correspondent countries' leaders were compared after being profiled by Profiler Plus. The results indicated that the leaders of embedded cultures were significantly more cooperative than autonomous cultures after holding the control variables constant. The findings were discussed in the light of relevant literature. © 2016 International Union of Psychological Science.
ERIC Educational Resources Information Center
Yu, Jiang; Williford, William R.
1991-01-01
Used sample from New York State Driver License File to mathematically extend dimension of file so that data purging procedure exerts minimum influence on calculation of drinking-driving recidivism. Examined impact of dimension of data on recidivism rate and mathematically extended file until impact of data dimension was minimum. Calculated New…
Fractal Dimension Analysis of Transient Visual Evoked Potentials: Optimisation and Applications.
Boon, Mei Ying; Henry, Bruce Ian; Chu, Byoung Sun; Basahi, Nour; Suttle, Catherine May; Luu, Chi; Leung, Harry; Hing, Stephen
2016-01-01
The visual evoked potential (VEP) provides a time series signal response to an external visual stimulus at the location of the visual cortex. The major VEP signal components, peak latency and amplitude, may be affected by disease processes. Additionally, the VEP contains fine detailed and non-periodic structure, of presently unclear relevance to normal function, which may be quantified using the fractal dimension. The purpose of this study is to provide a systematic investigation of the key parameters in the measurement of the fractal dimension of VEPs, to develop an optimal analysis protocol for application. VEP time series were mathematically transformed using delay time, τ, and embedding dimension, m, parameters. The fractal dimension of the transformed data was obtained from a scaling analysis based on straight line fits to the numbers of pairs of points with separation less than r versus log(r) in the transformed space. Optimal τ, m, and scaling analysis were obtained by comparing the consistency of results using different sampling frequencies. The optimised method was then piloted on samples of normal and abnormal VEPs. Consistent fractal dimension estimates were obtained using τ = 4 ms, designating the fractal dimension = D2 of the time series based on embedding dimension m = 7 (for 3606 Hz and 5000 Hz), m = 6 (for 1803 Hz) and m = 5 (for 1000Hz), and estimating D2 for each embedding dimension as the steepest slope of the linear scaling region in the plot of log(C(r)) vs log(r) provided the scaling region occurred within the middle third of the plot. Piloting revealed that fractal dimensions were higher from the sampled abnormal than normal achromatic VEPs in adults (p = 0.02). Variances of fractal dimension were higher from the abnormal than normal chromatic VEPs in children (p = 0.01). A useful analysis protocol to assess the fractal dimension of transformed VEPs has been developed.
Application of Local Linear Embedding to Nonlinear Exploratory Latent Structure Analysis
ERIC Educational Resources Information Center
Wang, Haonan; Iyer, Hari
2007-01-01
In this paper we discuss the use of a recent dimension reduction technique called Locally Linear Embedding, introduced by Roweis and Saul, for performing an exploratory latent structure analysis. The coordinate variables from the locally linear embedding describing the manifold on which the data reside serve as the latent variable scores. We…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arendt, Dustin L.; Volkova, Svitlana
Analyzing and visualizing large amounts of social media communications and contrasting short-term conversation changes over time and geo-locations is extremely important for commercial and government applications. Earlier approaches for large-scale text stream summarization used dynamic topic models and trending words. Instead, we rely on text embeddings – low-dimensional word representations in a continuous vector space where similar words are embedded nearby each other. This paper presents ESTEEM,1 a novel tool for visualizing and evaluating spatiotemporal embeddings learned from streaming social media texts. Our tool allows users to monitor and analyze query words and their closest neighbors with an interactive interface.more » We used state-of- the-art techniques to learn embeddings and developed a visualization to represent dynamically changing relations between words in social media over time and other dimensions. This is the first interactive visualization of streaming text representations learned from social media texts that also allows users to contrast differences across multiple dimensions of the data.« less
NASA Astrophysics Data System (ADS)
Bhardwaj, Rupali
2018-03-01
Reversible data hiding means embedding a secret message in a cover image in such a manner, to the point that in the midst of extraction of the secret message, the cover image and, furthermore, the secret message are recovered with no error. The goal of by far most of the reversible data hiding algorithms is to have improved the embedding rate and enhanced visual quality of stego image. An improved encrypted-domain-based reversible data hiding algorithm to embed two binary bits in each gray pixel of original cover image with minimum distortion of stego-pixels is employed in this paper. Highlights of the proposed algorithm are minimum distortion of pixel's value, elimination of underflow and overflow problem, and equivalence of stego image and cover image with a PSNR of ∞ (for Lena, Goldhill, and Barbara image). The experimental outcomes reveal that in terms of average PSNR and embedding rate, for natural images, the proposed algorithm performed better than other conventional ones.
The Bargmann-Wigner equations in spherical space
NASA Astrophysics Data System (ADS)
McKeon, D. G. C.; Sherry, T. N.
2006-01-01
The Bargmann-Wigner formalism is adapted to spherical surfaces embedded in three to eleven dimensions. This is demonstrated to generate wave equations in spherical space for a variety of antisymmetric tensor fields. Some of these equations are gauge invariant for particular values of the parameters characterizing them. For spheres embedded in three, four, and five dimensions, this gauge invariance can be generalized so as to become non-Abelian. This non-Abelian gauge invariance is shown to be a property of second-order models for two index antisymmetric tensor fields in any number of dimensions. The O(3) model is quantized and the two-point function is shown to vanish at the one-loop order.
Locally linear embedding: dimension reduction of massive protostellar spectra
NASA Astrophysics Data System (ADS)
Ward, J. L.; Lumsden, S. L.
2016-09-01
We present the results of the application of locally linear embedding (LLE) to reduce the dimensionality of dereddened and continuum subtracted near-infrared spectra using a combination of models and real spectra of massive protostars selected from the Red MSX Source survey data base. A brief comparison is also made with two other dimension reduction techniques; principal component analysis (PCA) and Isomap using the same set of spectra as well as a more advanced form of LLE, Hessian locally linear embedding. We find that whilst LLE certainly has its limitations, it significantly outperforms both PCA and Isomap in classification of spectra based on the presence/absence of emission lines and provides a valuable tool for classification and analysis of large spectral data sets.
Recurrence plots of discrete-time Gaussian stochastic processes
NASA Astrophysics Data System (ADS)
Ramdani, Sofiane; Bouchara, Frédéric; Lagarde, Julien; Lesne, Annick
2016-09-01
We investigate the statistical properties of recurrence plots (RPs) of data generated by discrete-time stationary Gaussian random processes. We analytically derive the theoretical values of the probabilities of occurrence of recurrence points and consecutive recurrence points forming diagonals in the RP, with an embedding dimension equal to 1. These results allow us to obtain theoretical values of three measures: (i) the recurrence rate (REC) (ii) the percent determinism (DET) and (iii) RP-based estimation of the ε-entropy κ(ε) in the sense of correlation entropy. We apply these results to two Gaussian processes, namely first order autoregressive processes and fractional Gaussian noise. For these processes, we simulate a number of realizations and compare the RP-based estimations of the three selected measures to their theoretical values. These comparisons provide useful information on the quality of the estimations, such as the minimum required data length and threshold radius used to construct the RP.
Miniaturization of metamaterial electrical resonators at the terahertz spectrum
NASA Astrophysics Data System (ADS)
Karamanos, Theodosios D.; Kantartzis, Nikolaos V.
2014-05-01
An efficient methodology for the modification of electrical resonators in order to be readily applicable at the terahertz regime is developed in this paper. To this aim, the proposed miniaturization technique starts from the conventional resonator which, without any change, exhibits the lowest possible electrical resonance for minimum dimensions. Subsequently, a set of interdigital capacitors is embedded in the original structure to increase capaci- tance, while their impact on the main resonance is investigated through computational simulations. Furthermore, to augment the inductance of the initial resonator, and, hence reduce the resonance frequency, the concept of spiral inductor elements is introduced. Again, results for the featured configuration with the additional elements are numerically obtained and all effects due to their presence are carefully examined. Finally, the new alterations are combined together and their in influence on the resonance position and quality is thoroughly studied.
Optimization of Selected Remote Sensing Algorithms for Embedded NVIDIA Kepler GPU Architecture
NASA Technical Reports Server (NTRS)
Riha, Lubomir; Le Moigne, Jacqueline; El-Ghazawi, Tarek
2015-01-01
This paper evaluates the potential of embedded Graphic Processing Units in the Nvidias Tegra K1 for onboard processing. The performance is compared to a general purpose multi-core CPU and full fledge GPU accelerator. This study uses two algorithms: Wavelet Spectral Dimension Reduction of Hyperspectral Imagery and Automated Cloud-Cover Assessment (ACCA) Algorithm. Tegra K1 achieved 51 for ACCA algorithm and 20 for the dimension reduction algorithm, as compared to the performance of the high-end 8-core server Intel Xeon CPU with 13.5 times higher power consumption.
Minimum weight structural sandwich
Edward W. Kuenzi
1965-01-01
This note presents theoretical analyses for determination of dimensions of structural sandwich of minimum weight that will have certain stiffness and load-carrying capabilities. Included is a brief discussion of the resultant minimum weight configurations.
Percolation of spatially constraint networks
NASA Astrophysics Data System (ADS)
Li, Daqing; Li, Guanliang; Kosmidis, Kosmas; Stanley, H. E.; Bunde, Armin; Havlin, Shlomo
2011-03-01
We study how spatial constraints are reflected in the percolation properties of networks embedded in one-dimensional chains and two-dimensional lattices. We assume long-range connections between sites on the lattice where two sites at distance r are chosen to be linked with probability p(r)~r-δ. Similar distributions have been found in spatially embedded real networks such as social and airline networks. We find that for networks embedded in two dimensions, with 2<δ<4, the percolation properties show new intermediate behavior different from mean field, with critical exponents that depend on δ. For δ<2, the percolation transition belongs to the universality class of percolation in Erdös-Rényi networks (mean field), while for δ>4 it belongs to the universality class of percolation in regular lattices. For networks embedded in one dimension, we find that, for δ<1, the percolation transition is mean field. For 1<δ<2, the critical exponents depend on δ, while for δ>2 there is no percolation transition as in regular linear chains.
49 CFR Appendix A to Part 223 - Certification of Glazing Materials
Code of Federal Regulations, 2011 CFR
2011-10-01
... material to be tested (Target Material) shall be a full scale sample of the largest dimension intended to... weight impacts at a minimum of 960 feet per second velocity. (ii) Large Object Impact in which a cinder block of 24 lbs minimum weight with dimensions of 8 inches by 8 inches by 16 inches nominally impacts at...
Farre, Albert; Wood, Victoria; McDonagh, Janet E; Parr, Jeremy R; Reape, Debbie; Rapley, Tim
2016-07-01
We aimed to (i) explore how health professionals and managers who work with young people seek to define developmentally appropriate healthcare (DAH), (ii) identify the range of conceptual dimensions present in their definitions and (iii) explore the controversies embedded in their characterisations of DAH. A qualitative multisite ethnographic study was conducted across three hospitals in England. We undertook face-to-face semi-structured interviews with health professionals and managers; and non-participant observation in clinics, wards and meetings. Anonymised field notes and interview transcripts were analysed using thematic analysis. The theme 'conceptualisations of DAH' was then further analysed, and the resulting themes categorised to form conceptual dimensions. We recruited 192 participants and conducted 65 interviews (41 with health professionals and 24 with managers) and approximately 1600 hours of non-participant observations (involving 103 health professionals and 72 managers). Despite the wide range of definitions provided by participants, five conceptual dimensions of DAH were identified: (i) biopsychosocial development and holistic care, (ii) acknowledgement of young people as a distinct group, (iii) adjustment of care as the young person develops, (iv) empowerment of the young person by embedding health education and health promotion and (v) interdisciplinary and interorganisational work. Also, some controversies were identified within most dimensions. This study illustrates the lack of a generalised definition of DAH for young people among UK health professionals and managers, and presents a set of five core dimensions that can inform future research to help define and evaluate DAH for young people. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Na, Muzi; Jennings, Larissa; Talegawkar, Sameera A; Ahmed, Saifuddin
2015-12-01
To explore the relationship between women's empowerment and WHO recommended infant and young child feeding (IYCF) practices in sub-Saharan Africa. Analysis was conducted using data from ten Demographic and Health Surveys between 2010 and 2013. Women's empowerment was assessed by nine standard items covering three dimensions: economic, socio-familial and legal empowerment. Three core IYCF practices examined were minimum dietary diversity, minimum meal frequency and minimum acceptable diet. Separate multivariable logistic regression models were applied for the IYCF practices on dimensional and overall empowerment in each country. Benin, Burkina Faso, Ethiopia, Mali, Niger, Nigeria, Rwanda, Sierra Leone, Uganda and Zimbabwe. Youngest singleton children aged 6-23 months and their mothers (n 15 153). Less than 35 %, 60 % and 18 % of children 6-23 months of age met the criterion of minimum dietary diversity, minimum meal frequency and minimum acceptable diet, respectively. In general, likelihood of meeting the recommended IYCF criteria was positively associated with the economic dimension of women's empowerment. Socio-familial empowerment was negatively associated with the three feeding criteria, except in Zimbabwe. The legal dimension of empowerment did not show any clear pattern in the associations. Greater overall empowerment of women was consistently and positively associated with multiple IYCF practices in Mali, Rwanda and Sierra Leone. However, consistent negative relationships were found in Benin and Niger. Null or mixed results were observed in the remaining countries. The importance of women's empowerment for IYCF practices needs to be discussed by context and by dimension of empowerment.
NASA Astrophysics Data System (ADS)
Yang, Zih-Ying; Su, Chen-Wei; Chen, Kuo-Ping
2018-01-01
This study sought to optimize the dimensional characteristics of paired-strips gold nanoantennas embedded in a P3HT: PCBM thin-film by taking into account the tradeoff between the size of the nanostructures and absorber layer as well as the gaps between nanoparticles, to maximize the effective absorption enhancement. The average enhancement behavior within the working region was discussed using integral analysis, which is important for overall enhancement. The discussion would focus on comparing the bands' features of paired-strips nanoantennas embedded in a dielectric thin-film, and in air. By the average absorption 3D slices plots, in which the dimension width, height, and gap are changed with a fixed wavelength; the optimized dimension of paired-strips nanoantennas could be realized. Fixing the period (400 nm) of paired-strips nanoantennas embedded in P3HT:PCBM thin-films (120 nm in thickness) enhanced absorption by 9.8 times.
NASA Astrophysics Data System (ADS)
Aytaç Korkmaz, Sevcan; Binol, Hamidullah
2018-03-01
Patients who die from stomach cancer are still present. Early diagnosis is crucial in reducing the mortality rate of cancer patients. Therefore, computer aided methods have been developed for early detection in this article. Stomach cancer images were obtained from Fırat University Medical Faculty Pathology Department. The Local Binary Patterns (LBP) and Histogram of Oriented Gradients (HOG) features of these images are calculated. At the same time, Sammon mapping, Stochastic Neighbor Embedding (SNE), Isomap, Classical multidimensional scaling (MDS), Local Linear Embedding (LLE), Linear Discriminant Analysis (LDA), t-Distributed Stochastic Neighbor Embedding (t-SNE), and Laplacian Eigenmaps methods are used for dimensional the reduction of the features. The high dimension of these features has been reduced to lower dimensions using dimensional reduction methods. Artificial neural networks (ANN) and Random Forest (RF) classifiers were used to classify stomach cancer images with these new lower feature sizes. New medical systems have developed to measure the effects of these dimensions by obtaining features in different dimensional with dimensional reduction methods. When all the methods developed are compared, it has been found that the best accuracy results are obtained with LBP_MDS_ANN and LBP_LLE_ANN methods.
Rasch Analysis for Binary Data with Nonignorable Nonresponses
ERIC Educational Resources Information Center
Bertoli-Barsotti, Lucio; Punzo, Antonio
2013-01-01
This paper introduces a two-dimensional Item Response Theory (IRT) model to deal with nonignorable nonresponses in tests with dichotomous items. One dimension provides information about the omitting behavior, while the other dimension is related to the person's "ability". The idea of embedding an IRT model for missingness into the measurement…
Permutation entropy with vector embedding delays
NASA Astrophysics Data System (ADS)
Little, Douglas J.; Kane, Deb M.
2017-12-01
Permutation entropy (PE) is a statistic used widely for the detection of structure within a time series. Embedding delay times at which the PE is reduced are characteristic timescales for which such structure exists. Here, a generalized scheme is investigated where embedding delays are represented by vectors rather than scalars, permitting PE to be calculated over a (D -1 ) -dimensional space, where D is the embedding dimension. This scheme is applied to numerically generated noise, sine wave and logistic map series, and experimental data sets taken from a vertical-cavity surface emitting laser exhibiting temporally localized pulse structures within the round-trip time of the laser cavity. Results are visualized as PE maps as a function of embedding delay, with low PE values indicating combinations of embedding delays where correlation structure is present. It is demonstrated that vector embedding delays enable identification of structure that is ambiguous or masked, when the embedding delay is constrained to scalar form.
Variability of fractal dimension of solar radio flux
NASA Astrophysics Data System (ADS)
Bhatt, Hitaishi; Sharma, Som Kumar; Trivedi, Rupal; Vats, Hari Om
2018-04-01
In the present communication, the variation of the fractal dimension of solar radio flux is reported. Solar radio flux observations on a day to day basis at 410, 1415, 2695, 4995, and 8800 MHz are used in this study. The data were recorded at Learmonth Solar Observatory, Australia from 1988 to 2009 covering an epoch of two solar activity cycles (22 yr). The fractal dimension is calculated for the listed frequencies for this period. The fractal dimension, being a measure of randomness, represents variability of solar radio flux at shorter time-scales. The contour plot of fractal dimension on a grid of years versus radio frequency suggests high correlation with solar activity. Fractal dimension increases with increasing frequency suggests randomness increases towards the inner corona. This study also shows that the low frequency is more affected by solar activity (at low frequency fractal dimension difference between solar maximum and solar minimum is 0.42) whereas, the higher frequency is less affected by solar activity (here fractal dimension difference between solar maximum and solar minimum is 0.07). A good positive correlation is found between fractal dimension averaged over all frequencies and yearly averaged sunspot number (Pearson's coefficient is 0.87).
36 CFR 1192.4 - Miscellaneous instructions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... General § 1192.4 Miscellaneous instructions. (a) Dimensional conventions. Dimensions that are not noted as minimum or maximum are absolute. (b) Dimensional tolerances. All dimensions are subject to conventional...
36 CFR 1192.4 - Miscellaneous instructions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... General § 1192.4 Miscellaneous instructions. (a) Dimensional conventions. Dimensions that are not noted as minimum or maximum are absolute. (b) Dimensional tolerances. All dimensions are subject to conventional...
36 CFR 1192.4 - Miscellaneous instructions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... General § 1192.4 Miscellaneous instructions. (a) Dimensional conventions. Dimensions that are not noted as minimum or maximum are absolute. (b) Dimensional tolerances. All dimensions are subject to conventional...
ERIC Educational Resources Information Center
Anderson, J. M.
1978-01-01
A method is described for preparing large gelatine-embedded soil sections for ecological studies. Sampling methods reduce structural disturbance of the samples to a minimum and include freezing the samples in the field to kill soil invertebrates in their natural microhabitats. Projects are suggested for upper secondary school students. (Author/BB)
Anthropometric Accommodation in Space Suit Design
NASA Technical Reports Server (NTRS)
Rajulu, Sudhakar; Thaxton, Sherry
2007-01-01
Design requirements for next generation hardware are in process at NASA. Anthropometry requirements are given in terms of minimum and maximum sizes for critical dimensions that hardware must accommodate. These dimensions drive vehicle design and suit design, and implicitly have an effect on crew selection and participation. At this stage in the process, stakeholders such as cockpit and suit designers were asked to provide lists of dimensions that will be critical for their design. In addition, they were asked to provide technically feasible minimum and maximum ranges for these dimensions. Using an adjusted 1988 Anthropometric Survey of U.S. Army (ANSUR) database to represent a future astronaut population, the accommodation ranges provided by the suit critical dimensions were calculated. This project involved participation from the Anthropometry and Biomechanics facility (ABF) as well as suit designers, with suit designers providing expertise about feasible hardware dimensions and the ABF providing accommodation analysis. The initial analysis provided the suit design team with the accommodation levels associated with the critical dimensions provided early in the study. Additional outcomes will include a comparison of principal components analysis as an alternate method for anthropometric analysis.
36 CFR § 1192.4 - Miscellaneous instructions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... General § 1192.4 Miscellaneous instructions. (a) Dimensional conventions. Dimensions that are not noted as minimum or maximum are absolute. (b) Dimensional tolerances. All dimensions are subject to conventional...
Verrill, Clare; Perry-Keene, Joanna; Srigley, John R; Zhou, Ming; Humphrey, Peter A; Lopez-Beltran, Antonio; Egevad, Lars; Ulbright, Thomas M; Tickoo, Satish K; Epstein, Jonathan I; Compérat, Eva; Berney, Daniel M
2018-06-01
The International Society of Urological Pathology held a conference on issues in testicular and penile pathology in Boston in March 2015, which included a presentation by the testis macroscopic features working group. The presentation focused on current published guidance for macroscopic handling of testicular tumors and retroperitoneal lymph node dissections with a summary of results from an online survey of members preceding the conference. The survey results were used to initiate discussions, but decisions on practice were made by expert consensus rather than voting. The importance of comprehensive assessment at the time of gross dissection with confirmation of findings by microscopic assessment was underscored. For example, the anatomic landmarks denoting the distinction of hilar soft tissue invasion (pT2) from spermatic cord invasion (pT3 category) can only be determined by careful macroscopic assessment in many cases. Other recommendations were to routinely sample epididymis, rete testis, hilar soft tissue, and tunica vaginalis in order to confirm macroscopic invasion of these structures or if not macroscopically evident, to exclude subtle microscopic invasion. Tumors 2 cm or less in greatest dimension should be completely embedded. If the tumor is >2 cm in greatest dimension, 10 blocks or a minimum of 1 to 2 additional blocks per centimeter should be taken (whichever is greater).
FDTD simulation of amorphous silicon waveguides for microphotonics applications
NASA Astrophysics Data System (ADS)
Fantoni, A.; Lourenço, P.; Pinho, P.; Vieira, M.,
2017-05-01
In this work we correlate the dimension of the waveguide with small variations of the refractive index of the material used for the waveguide core. We calculate the effective modal refractive index for different dimensions of the waveguide and with slightly variation of the refractive index of the core material. These results are used as an input for a set of Finite Difference Time Domain simulation, directed to study the characteristics of amorphous silicon waveguides embedded in a SiO2 cladding. The study considers simple linear waveguides with rectangular section for studying the modal attenuation expected at different wavelengths. Transmission efficiency is determined analyzing the decay of the light power along the waveguides. As far as near infrared wavelengths are considered, a-Si:H shows a behavior highly dependent on the light wavelength and its extinction coefficient rapidly increases as operating frequency goes into visible spectrum range. The simulation results show that amorphous silicon can be considered a good candidate for waveguide material core whenever the waveguide length is as short as a few centimeters. The maximum transmission length is highly affected by the a-Si:H defect density, the mid-gap density of states and by the waveguide section area. The simulation results address a minimum requirement of 300nm×400nm waveguide section in order to keep attenuation below 1 dB cm-1.
Going beyond Procedure: Engaging with the Ethical Complexities of Being an Embedded Researcher
ERIC Educational Resources Information Center
Rowley, Harriet
2014-01-01
This article is a reflection upon the ethical dimension of my work and practice as an embedded researcher during my doctorate. To begin with, I describe my experiences of gaining ethical approval from The University of Manchester while also highlighting some of the concerns that were raised by the ethics board. This leads me to recognise how the…
The provision of clearances accuracy in piston - cylinder mating
NASA Astrophysics Data System (ADS)
Glukhov, V. I.; Shalay, V. V.
2017-08-01
The paper is aimed at increasing the quality of the pumping equipment in oil and gas industry. The main purpose of the study is to stabilize maximum values of productivity and durability of the pumping equipment based on the selective assembly of the cylinder-piston kinematic mating by optimization criterion. It is shown that the minimum clearance in the piston-cylinder mating is formed by maximum material dimensions. It is proved that maximum material dimensions are characterized by their own laws of distribution within the tolerance limits for the diameters of the cylinder internal mirror and the outer cylindrical surface of the piston. At that, their dispersion zones should be divided into size groups with a group tolerance equal to half the tolerance for the minimum clearance. The techniques for measuring the material dimensions - the smallest cylinder diameter and the largest piston diameter according to the envelope condition - are developed for sorting them into size groups. Reliable control of the dimensions precision ensures optimal minimum clearances of the piston-cylinder mating in all the size groups of the pumping equipment, necessary for increasing the equipment productivity and durability during the production, operation and repair processes.
16 CFR 304.5 - Marking requirements for imitation political items.
Code of Federal Regulations, 2013 CFR
2013-01-01
...-serif numerals. Each numeral shall have a vertical dimension of not less than two millimeters (2.0 mm... reproduction, whichever is the lesser. The minimum total horizontal dimension for the four numerals composing... year in sans-serif numerals. Each numeral shall have a vertical dimension of not less than two...
16 CFR 304.5 - Marking requirements for imitation political items.
Code of Federal Regulations, 2014 CFR
2014-01-01
...-serif numerals. Each numeral shall have a vertical dimension of not less than two millimeters (2.0 mm... reproduction, whichever is the lesser. The minimum total horizontal dimension for the four numerals composing... year in sans-serif numerals. Each numeral shall have a vertical dimension of not less than two...
16 CFR 304.5 - Marking requirements for imitation political items.
Code of Federal Regulations, 2012 CFR
2012-01-01
...-serif numerals. Each numeral shall have a vertical dimension of not less than two millimeters (2.0 mm... reproduction, whichever is the lesser. The minimum total horizontal dimension for the four numerals composing... year in sans-serif numerals. Each numeral shall have a vertical dimension of not less than two...
Construction of Optimally Reduced Empirical Model by Spatially Distributed Climate Data
NASA Astrophysics Data System (ADS)
Gavrilov, A.; Mukhin, D.; Loskutov, E.; Feigin, A.
2016-12-01
We present an approach to empirical reconstruction of the evolution operator in stochastic form by space-distributed time series. The main problem in empirical modeling consists in choosing appropriate phase variables which can efficiently reduce the dimension of the model at minimal loss of information about system's dynamics which consequently leads to more robust model and better quality of the reconstruction. For this purpose we incorporate in the model two key steps. The first step is standard preliminary reduction of observed time series dimension by decomposition via certain empirical basis (e. g. empirical orthogonal function basis or its nonlinear or spatio-temporal generalizations). The second step is construction of an evolution operator by principal components (PCs) - the time series obtained by the decomposition. In this step we introduce a new way of reducing the dimension of the embedding in which the evolution operator is constructed. It is based on choosing proper combinations of delayed PCs to take into account the most significant spatio-temporal couplings. The evolution operator is sought as nonlinear random mapping parameterized using artificial neural networks (ANN). Bayesian approach is used to learn the model and to find optimal hyperparameters: the number of PCs, the dimension of the embedding, the degree of the nonlinearity of ANN. The results of application of the method to climate data (sea surface temperature, sea level pressure) and their comparing with the same method based on non-reduced embedding are presented. The study is supported by Government of Russian Federation (agreement #14.Z50.31.0033 with the Institute of Applied Physics of RAS).
Cutting Symmetrical Recesses In Soft Ceramic Tiles
NASA Technical Reports Server (NTRS)
Nesotas, Tony C.; Tyler, Brent
1989-01-01
Simple tool cuts hemispherical recesses in soft ceramic tiles. Designed to expose wires of thermocouples embedded in tiles without damaging leads. Creates neat, precise holes around wires. End mill includes axial hole to accommodate thermocouple wires embedded in material to be cut. Wires pass into hole without being bent or broken. Dimensions in inches. Used in place of such tools as dental picks, tweezers, spatulas, and putty knives.
An improvement of the measurement of time series irreversibility with visibility graph approach
NASA Astrophysics Data System (ADS)
Wu, Zhenyu; Shang, Pengjian; Xiong, Hui
2018-07-01
We propose a method to improve the measure of real-valued time series irreversibility which contains two tools: the directed horizontal visibility graph and the Kullback-Leibler divergence. The degree of time irreversibility is estimated by the Kullback-Leibler divergence between the in and out degree distributions presented in the associated visibility graph. In our work, we reframe the in and out degree distributions by encoding them with different embedded dimensions used in calculating permutation entropy(PE). With this improved method, we can not only estimate time series irreversibility efficiently, but also detect time series irreversibility from multiple dimensions. We verify the validity of our method and then estimate the amount of time irreversibility of series generated by chaotic maps as well as global stock markets over the period 2005-2015. The result shows that the amount of time irreversibility reaches the peak with embedded dimension d = 3 under circumstances of experiment and financial markets.
49 CFR Appendix A to Part 224 - Schedule of Civil Penalties1
Code of Federal Regulations, 2010 CFR
2010-10-01
... § 224.105Sheeting dimensions and quantity: Failure to apply minimum amount of retroreflective sheeting in accordance with Table 2 2,500 5,000 Applying retroreflective sheeting of wrong dimensions 2,500 5...
Multiview Locally Linear Embedding for Effective Medical Image Retrieval
Shen, Hualei; Tao, Dacheng; Ma, Dianfu
2013-01-01
Content-based medical image retrieval continues to gain attention for its potential to assist radiological image interpretation and decision making. Many approaches have been proposed to improve the performance of medical image retrieval system, among which visual features such as SIFT, LBP, and intensity histogram play a critical role. Typically, these features are concatenated into a long vector to represent medical images, and thus traditional dimension reduction techniques such as locally linear embedding (LLE), principal component analysis (PCA), or laplacian eigenmaps (LE) can be employed to reduce the “curse of dimensionality”. Though these approaches show promising performance for medical image retrieval, the feature-concatenating method ignores the fact that different features have distinct physical meanings. In this paper, we propose a new method called multiview locally linear embedding (MLLE) for medical image retrieval. Following the patch alignment framework, MLLE preserves the geometric structure of the local patch in each feature space according to the LLE criterion. To explore complementary properties among a range of features, MLLE assigns different weights to local patches from different feature spaces. Finally, MLLE employs global coordinate alignment and alternating optimization techniques to learn a smooth low-dimensional embedding from different features. To justify the effectiveness of MLLE for medical image retrieval, we compare it with conventional spectral embedding methods. We conduct experiments on a subset of the IRMA medical image data set. Evaluation results show that MLLE outperforms state-of-the-art dimension reduction methods. PMID:24349277
Optical nondestructive dynamic measurements of wafer-scale encapsulated nanofluidic channels.
Liberman, Vladimir; Smith, Melissa; Weaver, Isaac; Rothschild, Mordechai
2018-05-20
Nanofluidic channels are of great interest for DNA sequencing, chromatography, and drug delivery. However, metrology of embedded or sealed nanochannels and measurement of their fill-state have remained extremely challenging. Existing techniques have been restricted to optical microscopy, which suffers from insufficient resolution, or scanning electron microscopy, which cannot measure sealed or embedded channels without cleaving the sample. Here, we demonstrate a novel method for accurately extracting nanochannel cross-sectional dimensions and monitoring fluid filling, utilizing spectroscopic ellipsometric scatterometry, combined with rigorous electromagnetic simulations. Our technique is capable of measuring channel dimensions with better than 5-nm accuracy and assessing channel filling within seconds. The developed technique is, thus, well suited for both process monitoring of channel fabrication as well as for studying complex phenomena of fluid flow through nanochannel structures.
Beyond Group: Multiple Person Tracking via Minimal Topology-Energy-Variation.
Gao, Shan; Ye, Qixiang; Xing, Junliang; Kuijper, Arjan; Han, Zhenjun; Jiao, Jianbin; Ji, Xiangyang
2017-12-01
Tracking multiple persons is a challenging task when persons move in groups and occlude each other. Existing group-based methods have extensively investigated how to make group division more accurately in a tracking-by-detection framework; however, few of them quantify the group dynamics from the perspective of targets' spatial topology or consider the group in a dynamic view. Inspired by the sociological properties of pedestrians, we propose a novel socio-topology model with a topology-energy function to factor the group dynamics of moving persons and groups. In this model, minimizing the topology-energy-variance in a two-level energy form is expected to produce smooth topology transitions, stable group tracking, and accurate target association. To search for the strong minimum in energy variation, we design the discrete group-tracklet jump moves embedded in the gradient descent method, which ensures that the moves reduce the energy variation of group and trajectory alternately in the varying topology dimension. Experimental results on both RGB and RGB-D data sets show the superiority of our proposed model for multiple person tracking in crowd scenes.
16 CFR 304.6 - Marking requirements for imitation numismatic items.
Code of Federal Regulations, 2012 CFR
2012-01-01
...” in sans-serif letters having a vertical dimension of not less than two millimeters (2.0 mm) or not... minimum total horizontal dimension of the word “COPY” shall be six millimeters (6.0 mm) or not less than... nonincusable material shall be imprinted with the word “COPY” in sans-serif letters having a vertical dimension...
16 CFR 304.6 - Marking requirements for imitation numismatic items.
Code of Federal Regulations, 2013 CFR
2013-01-01
...” in sans-serif letters having a vertical dimension of not less than two millimeters (2.0 mm) or not... minimum total horizontal dimension of the word “COPY” shall be six millimeters (6.0 mm) or not less than... nonincusable material shall be imprinted with the word “COPY” in sans-serif letters having a vertical dimension...
16 CFR 304.6 - Marking requirements for imitation numismatic items.
Code of Federal Regulations, 2014 CFR
2014-01-01
...” in sans-serif letters having a vertical dimension of not less than two millimeters (2.0 mm) or not... minimum total horizontal dimension of the word “COPY” shall be six millimeters (6.0 mm) or not less than... nonincusable material shall be imprinted with the word “COPY” in sans-serif letters having a vertical dimension...
16 CFR 304.6 - Marking requirements for imitation numismatic items.
Code of Federal Regulations, 2011 CFR
2011-01-01
...” in sans-serif letters having a vertical dimension of not less than two millimeters (2.0 mm) or not... minimum total horizontal dimension of the word “COPY” shall be six millimeters (6.0 mm) or not less than... nonincusable material shall be imprinted with the word “COPY” in sans-serif letters having a vertical dimension...
Parametric dense stereovision implementation on a system-on chip (SoC).
Gardel, Alfredo; Montejo, Pablo; García, Jorge; Bravo, Ignacio; Lázaro, José L
2012-01-01
This paper proposes a novel hardware implementation of a dense recovery of stereovision 3D measurements. Traditionally 3D stereo systems have imposed the maximum number of stereo correspondences, introducing a large restriction on artificial vision algorithms. The proposed system-on-chip (SoC) provides great performance and efficiency, with a scalable architecture available for many different situations, addressing real time processing of stereo image flow. Using double buffering techniques properly combined with pipelined processing, the use of reconfigurable hardware achieves a parametrisable SoC which gives the designer the opportunity to decide its right dimension and features. The proposed architecture does not need any external memory because the processing is done as image flow arrives. Our SoC provides 3D data directly without the storage of whole stereo images. Our goal is to obtain high processing speed while maintaining the accuracy of 3D data using minimum resources. Configurable parameters may be controlled by later/parallel stages of the vision algorithm executed on an embedded processor. Considering hardware FPGA clock of 100 MHz, image flows up to 50 frames per second (fps) of dense stereo maps of more than 30,000 depth points could be obtained considering 2 Mpix images, with a minimum initial latency. The implementation of computer vision algorithms on reconfigurable hardware, explicitly low level processing, opens up the prospect of its use in autonomous systems, and they can act as a coprocessor to reconstruct 3D images with high density information in real time.
Gauging hidden symmetries in two dimensions
NASA Astrophysics Data System (ADS)
Samtleben, Henning; Weidner, Martin
2007-08-01
We initiate the systematic construction of gauged matter-coupled supergravity theories in two dimensions. Subgroups of the affine global symmetry group of toroidally compactified supergravity can be gauged by coupling vector fields with minimal couplings and a particular topological term. The gauge groups typically include hidden symmetries that are not among the target-space isometries of the ungauged theory. The gaugings constructed in this paper are described group-theoretically in terms of a constant embedding tensor subject to a number of constraints which parametrizes the different theories and entirely encodes the gauged Lagrangian. The prime example is the bosonic sector of the maximally supersymmetric theory whose ungauged version admits an affine fraktur e9 global symmetry algebra. The various parameters (related to higher-dimensional p-form fluxes, geometric and non-geometric fluxes, etc.) which characterize the possible gaugings, combine into an embedding tensor transforming in the basic representation of fraktur e9. This yields an infinite-dimensional class of maximally supersymmetric theories in two dimensions. We work out and discuss several examples of higher-dimensional origin which can be systematically analyzed using the different gradings of fraktur e9.
2016-02-26
say that A is a JL(m,d,)-embedding of S into Cm. Linear JL(m,d,)-embeddings are closely related to the Restricted Isometry Property [9, 4, 18...holds ∀x ∈ Cd containing at most s nonzero coordinates. In this case we will say that A is RIP(s,). In particular, the following theorem due to Krahmer...implement reliable edge detector functions, especially in the presence of noise. Needless to say , the same issues exist in two dimensions, as
Chen, Dong; Eisley, Noel A.; Steinmacher-Burow, Burkhard; Heidelberger, Philip
2013-01-29
A computer implemented method and a system for routing data packets in a multi-dimensional computer network. The method comprises routing a data packet among nodes along one dimension towards a root node, each node having input and output communication links, said root node not having any outgoing uplinks, and determining at each node if the data packet has reached a predefined coordinate for the dimension or an edge of the subrectangle for the dimension, and if the data packet has reached the predefined coordinate for the dimension or the edge of the subrectangle for the dimension, determining if the data packet has reached the root node, and if the data packet has not reached the root node, routing the data packet among nodes along another dimension towards the root node.
Teeter, Matthew G; Kopacz, Alexander J; Nikolov, Hristo N; Holdsworth, David W
2015-01-01
Additive manufacturing continues to increase in popularity and is being used in applications such as biomaterial ingrowth that requires sub-millimeter dimensional accuracy. The purpose of this study was to design a metrology test object for determining the capabilities of additive manufacturing systems to produce common objects, with a focus on those relevant to medical applications. The test object was designed with a variety of features of varying dimensions, including holes, cylinders, rectangles, gaps, and lattices. The object was built using selective laser melting, and the produced dimensions were compared to the target dimensions. Location of the test objects on the build plate did not affect dimensions. Features with dimensions less than 0.300 mm did not build or were overbuilt to a minimum of 0.300 mm. The mean difference between target and measured dimensions was less than 0.100 mm in all cases. The test object is applicable to multiple systems and materials, tests the effect of location on the build, uses a minimum of material, and can be measured with a variety of efficient metrology tools (including measuring microscopes and micro-CT). Investigators can use this test object to determine the limits of systems and adjust build parameters to achieve maximum accuracy. © IMechE 2014.
Time-lagged autoencoders: Deep learning of slow collective variables for molecular kinetics
NASA Astrophysics Data System (ADS)
Wehmeyer, Christoph; Noé, Frank
2018-06-01
Inspired by the success of deep learning techniques in the physical and chemical sciences, we apply a modification of an autoencoder type deep neural network to the task of dimension reduction of molecular dynamics data. We can show that our time-lagged autoencoder reliably finds low-dimensional embeddings for high-dimensional feature spaces which capture the slow dynamics of the underlying stochastic processes—beyond the capabilities of linear dimension reduction techniques.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to a line from stem to blossom end. When measuring for maximum size, “diameter” means the smallest dimension of the apple determined by...
Code of Federal Regulations, 2011 CFR
2011-01-01
... Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to a line from stem to blossom end. When measuring for maximum size, “diameter” means the smallest dimension of the apple determined by...
Code of Federal Regulations, 2013 CFR
2013-01-01
..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to... dimension of the apple determined by passing the apple through a round opening in any position. U.S...
Code of Federal Regulations, 2014 CFR
2014-01-01
..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to... dimension of the apple determined by passing the apple through a round opening in any position. U.S...
Code of Federal Regulations, 2010 CFR
2010-01-01
... Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to a line from stem to blossom end. When measuring for maximum size, “diameter” means the smallest dimension of the apple determined by...
Dimensions of Entrepreneurial Success: A Multilevel Study on Stakeholders of Micro-Enterprises
Razmus, Wiktor; Laguna, Mariola
2018-01-01
The study provides an insight into the indicators and dimensions of entrepreneurial success as evaluated from the external stockholders’ perspective. As each firm is embedded in a network of relations with stakeholders (business partners), understanding how they evaluate entrepreneurial success is important. The initial qualitative study in the form of in-depth interviews allowed us to identify the indicators of entrepreneurial success that are identified by external stakeholders of micro-firms. In the quantitative study on 475 stakeholders of 57 micro-firms, we identified the dimensions of entrepreneurial success. Using a multilevel approach, we found six dimensions of entrepreneurial success at the individual stakeholder level and four dimensions at the firm level. The results show that stakeholders perceive entrepreneurial success in terms of many dimensions, not focusing solely on economic indicators. This knowledge may inform micro-firm management and the strategies employed by practitioners supporting entrepreneurs. PMID:29892242
Viscoplastic Matrix Materials for Embedded 3D Printing.
Grosskopf, Abigail K; Truby, Ryan L; Kim, Hyoungsoo; Perazzo, Antonio; Lewis, Jennifer A; Stone, Howard A
2018-03-16
Embedded three-dimensional (EMB3D) printing is an emerging technique that enables free-form fabrication of complex architectures. In this approach, a nozzle is translated omnidirectionally within a soft matrix that surrounds and supports the patterned material. To optimize print fidelity, we have investigated the effects of matrix viscoplasticity on the EMB3D printing process. Specifically, we determine how matrix composition, print path and speed, and nozzle diameter affect the yielded region within the matrix. By characterizing the velocity and strain fields and analyzing the dimensions of the yielded regions, we determine that scaling relationships based on the Oldroyd number, Od, exist between these dimensions and the rheological properties of the matrix materials and printing parameters. Finally, we use EMB3D printing to create complex architectures within an elastomeric silicone matrix. Our methods and findings will both facilitate future characterization of viscoplastic matrices and motivate the development of new materials for EMB3D printing.
Assessment of codes, by-laws and regulations relating to air wells in building design
NASA Astrophysics Data System (ADS)
Fadzil, Sharifah Fairuz Syed; Karamazaman, Nazli
2017-10-01
Codes and by-laws concerning air well design (for buildings and lavatories) in Malaysia has been established in the Malaysian Uniform Building By-Laws UBBL number 40 (1) and (2) since the 1980s. Wells are there to fulfill the ventilation and daylighting requirements. The minimum well area according to building storey height are compared between UBBL and the Singapore's well requirements from the Building Construction Authority BCA. A visual and graphical representation (with schematics building and well diagrams drawn to scale) of the minimum well sizes and dimensions is given. It can be seen that if the minimum requirement of well size is used for buildings above 8 storeys high, a thin well resulted which is not proportionate to the building height. A proposed dimension is graphed and given to be used in the UBBL which translated to graphics (3 dimensional buildings drawn to scale) created a much better well proportion.
Diverse Power Iteration Embeddings and Its Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang H.; Yoo S.; Yu, D.
2014-12-14
Abstract—Spectral Embedding is one of the most effective dimension reduction algorithms in data mining. However, its computation complexity has to be mitigated in order to apply it for real-world large scale data analysis. Many researches have been focusing on developing approximate spectral embeddings which are more efficient, but meanwhile far less effective. This paper proposes Diverse Power Iteration Embeddings (DPIE), which not only retains the similar efficiency of power iteration methods but also produces a series of diverse and more effective embedding vectors. We test this novel method by applying it to various data mining applications (e.g. clustering, anomaly detectionmore » and feature selection) and evaluating their performance improvements. The experimental results show our proposed DPIE is more effective than popular spectral approximation methods, and obtains the similar quality of classic spectral embedding derived from eigen-decompositions. Moreover it is extremely fast on big data applications. For example in terms of clustering result, DPIE achieves as good as 95% of classic spectral clustering on the complex datasets but 4000+ times faster in limited memory environment.« less
Hu, Weiming; Gao, Jin; Xing, Junliang; Zhang, Chao; Maybank, Stephen
2017-01-01
An appearance model adaptable to changes in object appearance is critical in visual object tracking. In this paper, we treat an image patch as a two-order tensor which preserves the original image structure. We design two graphs for characterizing the intrinsic local geometrical structure of the tensor samples of the object and the background. Graph embedding is used to reduce the dimensions of the tensors while preserving the structure of the graphs. Then, a discriminant embedding space is constructed. We prove two propositions for finding the transformation matrices which are used to map the original tensor samples to the tensor-based graph embedding space. In order to encode more discriminant information in the embedding space, we propose a transfer-learning- based semi-supervised strategy to iteratively adjust the embedding space into which discriminative information obtained from earlier times is transferred. We apply the proposed semi-supervised tensor-based graph embedding learning algorithm to visual tracking. The new tracking algorithm captures an object's appearance characteristics during tracking and uses a particle filter to estimate the optimal object state. Experimental results on the CVPR 2013 benchmark dataset demonstrate the effectiveness of the proposed tracking algorithm.
Schütz, Kathleen; Placht, Anna-Maria; Paul, Birgit; Brüggemeier, Sophie; Gelinsky, Michael; Lode, Anja
2017-05-01
Biofabrication of tissue engineering constructs with tailored architecture and organized cell placement using rapid prototyping technologies is a major research focus in the field of regenerative therapies. This study describes a novel alginate-based material suitable for both cell embedding and fabrication of three-dimensional (3D) structures with predefined geometry by 3D plotting. The favourable printing properties of the material were achieved by using a simple strategy: addition of methylcellulose (MC) to a 3% alginate solution resulted in a strongly enhanced viscosity, which enabled accurate and easy deposition without high technical efforts. After scaffold plotting, the alginate chains were crosslinked with Ca 2+ ; MC did not contribute to the gelation and was released from the scaffolds during the following cultivation. The resulting constructs are characterized by high elasticity and stability, as well as an enhanced microporosity caused by the transient presence of MC. The suitability of the alginate/MC blend for cell embedding was evaluated by direct incorporation of mesenchymal stem cells during scaffold fabrication. The embedded cells showed high viability after 3 weeks of cultivation, which was similar to those of cells within pure alginate scaffolds which served as control. Maintenance of the differentiation potential of embedded cells, as an important requirement for the generation of functional tissue engineering constructs, was proven for adipogenic differentiation as a model for soft tissue formation. In conclusion, the temporary integration of MC into a low-concentrated alginate solution allowed the generation of scaffolds with dimensions in the range of centimetres without loss of the positive properties of low-concentrated alginate hydrogels with regard to cell embedding. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
Tewatia, D K; Tolakanahalli, R P; Paliwal, B R; Tomé, W A
2011-04-07
The underlying requirements for successful implementation of any efficient tumour motion management strategy are regularity and reproducibility of a patient's breathing pattern. The physiological act of breathing is controlled by multiple nonlinear feedback and feed-forward couplings. It would therefore be appropriate to analyse the breathing pattern of lung cancer patients in the light of nonlinear dynamical system theory. The purpose of this paper is to analyse the one-dimensional respiratory time series of lung cancer patients based on nonlinear dynamics and delay coordinate state space embedding. It is very important to select a suitable pair of embedding dimension 'm' and time delay 'τ' when performing a state space reconstruction. Appropriate time delay and embedding dimension were obtained using well-established methods, namely mutual information and the false nearest neighbour method, respectively. Establishing stationarity and determinism in a given scalar time series is a prerequisite to demonstrating that the nonlinear dynamical system that gave rise to the scalar time series exhibits a sensitive dependence on initial conditions, i.e. is chaotic. Hence, once an appropriate state space embedding of the dynamical system has been reconstructed, we show that the time series of the nonlinear dynamical systems under study are both stationary and deterministic in nature. Once both criteria are established, we proceed to calculate the largest Lyapunov exponent (LLE), which is an invariant quantity under time delay embedding. The LLE for all 16 patients is positive, which along with stationarity and determinism establishes the fact that the time series of a lung cancer patient's breathing pattern is not random or irregular, but rather it is deterministic in nature albeit chaotic. These results indicate that chaotic characteristics exist in the respiratory waveform and techniques based on state space dynamics should be employed for tumour motion management.
Reconfigurable, Bi-Directional Flexfet Level Shifter for Low-Power, Rad-Hard Integration
NASA Technical Reports Server (NTRS)
DeGregorio, Kelly; Wilson, Dale G.
2009-01-01
Two prototype Reconfigurable, Bi-directional Flexfet Level Shifters (ReBiLS) have been developed, where one version is a stand-alone component designed to interface between external low voltage and high voltage, and the other version is an embedded integrated circuit (IC) for interface between internal low-voltage logic and external high-voltage components. Targeting stand-alone and embedded circuits separately allows optimization for these distinct applications. Both ReBiLS designs use the commercially available 180-nm Flex fet Independently Double-Gated (IDG) SOI CMOS (silicon on insulator, complementary metal oxide semiconductor) technology. Embedded ReBiLS circuits were integrated with a Reed-Solomon (RS) encoder using CMOS Ultra-Low-Power Radiation Tolerant (CULPRiT) double-gated digital logic circuits. The scope of the project includes: creation of a new high-voltage process, development of ReBiLS circuit designs, and adjustment of the designs to maximize performance through simulation, layout, and manufacture of prototypes. The primary technical objectives were to develop a high-voltage, thick oxide option for the 180-nm Flexfet process, and to develop a stand-alone ReBiLS IC with two 8-channel I/O busses, 1.8 2.5 I/O on the low-voltage pins, 5.0-V-tolerant input and 3.3-V output I/O on the high-voltage pins, and 100-MHz minimum operation with 10-pF external loads. Another objective was to develop an embedded, rad-hard ReBiLS I/O cell with 0.5-V low-voltage operation for interface with core logic, 5.0-V-tolerant input and 3.3-V output I/O pins, and 100-MHz minimum operation with 10- pF external loads. A third objective was to develop a 0.5- V Reed-Solomon Encoder with embedded ReBilS I/O: Transfer the existing CULPRiT RS encoder from a 0.35-micron bulk-CMOS process to the ASI 180-nm Flexfet, rad-hard SOI Process. 0.5-V low-voltage core logic. 5.0-V-tolerant input and 3.3-V output I/O pins. 100-MHz minimum operation with 10- pF external loads. The stand-alone ReBiLS chip will allow system designers to provide efficient bi-directional communication between components operating at different voltages. Embedding the ReBiLS cells into the proven Reed-Solomon encoder will demonstrate the ability to support new product development in a commercially viable, rad-hard, scalable 180-nm SOI CMOS process.
On the Ck-embedding of Lorentzian manifolds in Ricci-flat spaces
NASA Astrophysics Data System (ADS)
Avalos, R.; Dahia, F.; Romero, C.
2018-05-01
In this paper, we investigate the problem of non-analytic embeddings of Lorentzian manifolds in Ricci-flat semi-Riemannian spaces. In order to do this, we first review some relevant results in the area and then motivate both the mathematical and physical interests in this problem. We show that any n-dimensional compact Lorentzian manifold (Mn, g), with g in the Sobolev space Hs+3, s >n/2 , admits an isometric embedding in a (2n + 2)-dimensional Ricci-flat semi-Riemannian manifold. The sharpest result available for these types of embeddings, in the general setting, comes as a corollary of Greene's remarkable embedding theorems R. Greene [Mem. Am. Math. Soc. 97, 1 (1970)], which guarantee the embedding of a compact n-dimensional semi-Riemannian manifold into an n(n + 5)-dimensional semi-Euclidean space, thereby guaranteeing the embedding into a Ricci-flat space with the same dimension. The theorem presented here improves this corollary in n2 + 3n - 2 codimensions by replacing the Riemann-flat condition with the Ricci-flat one from the beginning. Finally, we will present a corollary of this theorem, which shows that a compact strip in an n-dimensional globally hyperbolic space-time can be embedded in a (2n + 2)-dimensional Ricci-flat semi-Riemannian manifold.
Kinetics of diffusion-controlled annihilation with sparse initial conditions
Ben-Naim, Eli; Krapivsky, Paul
2016-12-16
Here, we study diffusion-controlled single-species annihilation with sparse initial conditions. In this random process, particles undergo Brownian motion, and when two particles meet, both disappear. We also focus on sparse initial conditions where particles occupy a subspace of dimension δ that is embedded in a larger space of dimension d. Furthermore, we find that the co-dimension Δ = d - δ governs the behavior. All particles disappear when the co-dimension is sufficiently small, Δ ≤ 2; otherwise, a finite fraction of particles indefinitely survive. We establish the asymptotic behavior of the probability S(t) that a test particle survives until time t. When the subspace is a line, δ = 1, we find inverse logarithmic decay,more » $$S\\sim {(\\mathrm{ln}t)}^{-1}$$, in three dimensions, and a modified power-law decay, $$S\\sim (\\mathrm{ln}t){t}^{-1/2}$$, in two dimensions. In general, the survival probability decays algebraically when Δ < 2, and there is an inverse logarithmic decay at the critical co-dimension Δ = 2.« less
NASA Technical Reports Server (NTRS)
Landis, W. J.; Song, M. J.; Leith, A.; McEwen, L.; McEwen, B. F.
1993-01-01
To define the ultrastructural accommodation of mineral crystals by collagen fibrils and other organic matrix components during vertebrate calcification, electron microscopic 3-D reconstructions were generated from the normally mineralizing leg tendons from the domestic turkey, Meleagris gallopavo. Embedded specimens containing initial collagen mineralizing sites were cut into 0.5-micron-thick sections and viewed and photographed at 1.0 MV in the Albany AEI-EM7 high-voltage electron microscope. Tomographic 3-D reconstructions were computed from a 2 degree tilt series of micrographs taken over a minimum angular range of +/- 60 degrees. Reconstructions of longitudinal tendon profiles confirm the presence of irregularly shaped mineral platelets, whose crystallographic c-axes are oriented generally parallel to one another and directed along the collagen long axes. The reconstructions also corroborate observations of a variable crystal length (up to 170 nm measured along crystallographic c-axes), the presence of crystals initially in either the hole or overlap zones of collagen, and crystal growth in the c-axis direction beyond these zones into adjacent overlap and other hole regions. Tomography shows for the first time that crystal width varies (30-45 nm) but crystal thickness is uniform (approximately 4-6 nm at the resolution limit of tomography); more crystals are located in the collagen hole zones than in the overlap regions at the earliest stages of tendon mineralization; the crystallographic c-axes of the platelets lie within +/- 15-20 degrees of one another rather than being perfectly parallel; adjacent platelets are spatially separated by a minimum of 4.2 +/- 1.0 nm; crystals apparently fuse in coplanar alignment to form larger platelets; development of crystals in width occurs to dimensions beyond single collagen hole zones; and a thin envelope of organic origin may be present along or just beneath the surfaces of individual mineral platelets. Implicit in the results is that the formation of crystals occurs at different sites and times by independent nucleation events in local regions of collagen. These data provide the first direct visual evidence from 3-D imaging describing the size, shape, orientation, and growth of mineral crystals in association with collagen of a normally mineralizing vertebrate tissue. They support concepts that c-axial crystal growth is unhindered by collage hole zone dimensions, that crystals are organized in the tendon in a series of generally parallel platelets, and that crystal growth in width across collagen fibrils may follow channels or grooves formed by adjacent hole zones in register.
Local adjacency metric dimension of sun graph and stacked book graph
NASA Astrophysics Data System (ADS)
Yulisda Badri, Alifiah; Darmaji
2018-03-01
A graph is a mathematical system consisting of a non-empty set of nodes and a set of empty sides. One of the topics to be studied in graph theory is the metric dimension. Application in the metric dimension is the navigation robot system on a path. Robot moves from one vertex to another vertex in the field by minimizing the errors that occur in translating the instructions (code) obtained from the vertices of that location. To move the robot must give different instructions (code). In order for the robot to move efficiently, the robot must be fast to translate the code of the nodes of the location it passes. so that the location vertex has a minimum distance. However, if the robot must move with the vertex location on a very large field, so the robot can not detect because the distance is too far.[6] In this case, the robot can determine its position by utilizing location vertices based on adjacency. The problem is to find the minimum cardinality of the required location vertex, and where to put, so that the robot can determine its location. The solution to this problem is the dimension of adjacency metric and adjacency metric bases. Rodrguez-Velzquez and Fernau combine the adjacency metric dimensions with local metric dimensions, thus becoming the local adjacency metric dimension. In the local adjacency metric dimension each vertex in the graph may have the same adjacency representation as the terms of the vertices. To obtain the local metric dimension of values in the graph of the Sun and the stacked book graph is used the construction method by considering the representation of each adjacent vertex of the graph.
Motion Coordination and Adaptation Using Deception and Human Interactions
2016-11-18
evolves an interface (front) by embedding it as a hyper - surface in a higher dimension, where time is the augmented dimension. Automatic handling of...the open- loop system trajectories. The results are depicted in Fig. 32. From the shape of the value function in Fig. 32(b) it is seen that the value is...estimate of the value function only over the area of the state space visited by the sampled (open- loop ) trajectories. In that sense, the areas not
An integrated fluorescence detection system in poly(dimethylsiloxane) for microfluidic applications.
Chabinyc, M L; Chiu, D T; McDonald, J C; Stroock, A D; Christian, J F; Karger, A M; Whitesides, G M
2001-09-15
This paper describes a prototype of an integrated fluorescence detection system that uses a microavalanche photodiode (microAPD) as the photodetector for microfluidic devices fabricated in poly(dimethylsiloxane) (PDMS). The prototype device consisted of a reusable detection system and a disposable microfluidic system that was fabricated using rapid prototyping. The first step of the procedure was the fabrication of microfluidic channels in PDMS and the encapsulation of a multimode optical fiber (100-microm core diameter) in the PDMS; the tip of the fiber was placed next to the side wall of one of the channels. The optical fiber was used to couple light into the microchannel for the excitation of fluorescent analytes. The photodetector, a prototype solid-state microAPD array, was embedded in a thick slab (1 cm) of PDMS. A thin (80 microm) colored polycarbonate filter was placed on the top of the embedded microAPD to absorb scattered excitation light before it reached the detector. The microAPD was placed below the microchannel and orthogonal to the axis of the optical fiber. The close proximity (approximately 200 microm) of the microAPD to the microchannel made it unnecessary to incorporate transfer optics; the pixel size of the microAPD (30 microm) matched the dimensions of the channels (50 microm). A blue light-emitting diode was used for fluorescence excitation. The microAPD was operated in Geiger mode to detect the fluorescence. The detection limit of the prototype (approximately 25 nM) was determined by finding the minimum detectable concentration of a solution of fluorescein. The device was used to detect the separation of a mixture of proteins and small molecules by capillary electrophoresis; the separation illustrated the suitability of this integrated fluorescence detection system for bioanalytical applications.
Produce yellow-poplar furniture dimension at minimum cost by using YELLOPOP
David G. Marten; David G. Marten
1986-01-01
Describes a computer program called YELLOPOP that determines the least-cost combination of lumber grades required to produce a given cutting order of furniture dimension parts. If the least-cost mix is not available, YELLOPOP can be used to determine the next best alternative. The steps involved in using the program are also described.
Kaur, Gagan Deep
2017-05-01
The design process in Kashmiri carpet weaving is distributed over a number of actors and artifacts and is mediated by a weaving notation called talim. The script encodes entire design in practice-specific symbols. This encoded script is decoded and interpreted via design-specific conventions by weavers to weave the design embedded in it. The cognitive properties of this notational system are described in the paper employing cognitive dimensions (CDs) framework of Green (People and computers, Cambridge University Press, Cambridge, 1989) and Blackwell et al. (Cognitive technology: instruments of mind-CT 2001, LNAI 2117, Springer, Berlin, 2001). After introduction to the practice, the design process is described in 'The design process' section which includes coding and decoding of talim. In 'Cognitive dimensions of talim' section, after briefly discussing CDs framework, the specific cognitive dimensions possessed by talim are described in detail.
Target intersection probabilities for parallel-line and continuous-grid types of search
McCammon, R.B.
1977-01-01
The expressions for calculating the probability of intersection of hidden targets of different sizes and shapes for parallel-line and continuous-grid types of search can be formulated by vsing the concept of conditional probability. When the prior probability of the orientation of a widden target is represented by a uniform distribution, the calculated posterior probabilities are identical with the results obtained by the classic methods of probability. For hidden targets of different sizes and shapes, the following generalizations about the probability of intersection can be made: (1) to a first approximation, the probability of intersection of a hidden target is proportional to the ratio of the greatest dimension of the target (viewed in plane projection) to the minimum line spacing of the search pattern; (2) the shape of the hidden target does not greatly affect the probability of the intersection when the largest dimension of the target is small relative to the minimum spacing of the search pattern, (3) the probability of intersecting a target twice for a particular type of search can be used as a lower bound if there is an element of uncertainty of detection for a particular type of tool; (4) the geometry of the search pattern becomes more critical when the largest dimension of the target equals or exceeds the minimum spacing of the search pattern; (5) for elongate targets, the probability of intersection is greater for parallel-line search than for an equivalent continuous square-grid search when the largest dimension of the target is less than the minimum spacing of the search pattern, whereas the opposite is true when the largest dimension exceeds the minimum spacing; (6) the probability of intersection for nonorthogonal continuous-grid search patterns is not greatly different from the probability of intersection for the equivalent orthogonal continuous-grid pattern when the orientation of the target is unknown. The probability of intersection for an elliptically shaped target can be approximated by treating the ellipse as intermediate between a circle and a line. A search conducted along a continuous rectangular grid can be represented as intermediate between a search along parallel lines and along a continuous square grid. On this basis, an upper and lower bound for the probability of intersection of an elliptically shaped target for a continuous rectangular grid can be calculated. Charts have been constructed that permit the values for these probabilities to be obtained graphically. The use of conditional probability allows the explorationist greater flexibility in considering alternate search strategies for locating hidden targets. ?? 1977 Plenum Publishing Corp.
Pandey, Sanjeev K; Patel, Dinesh K; Thakur, Ravi; Mishra, Durga P; Maiti, Pralay; Haldar, Chandana
2015-04-01
This study was carried out to synthesize quercetin (Qt) embedded poly(lactic acid) (PLA) nanoparticles (PLA-Qt) and to evaluate anti-cancer efficacy of PLA-Qt by using human breast cancer cells. PLA-Qt were synthesized by using novel emulsified nanoprecipitation technique with varying dimension of 32 ± 8 to 152 ± 9 nm of PLA-Qt with 62 ± 3% (w/w) entrapment efficiency by varying the concentration of polymer, emulsifier, drug and preparation temperature. The dimension of PLA-Qt was measured through transmission electron microscopy indicating larger particle size at higher concentration of PLA. The release rate of Qt from PLA-Qt was found to be more sustained for larger particle dimension (152 ± 9 nm) as compared to smaller particle dimension (32 ± 8 nm). Interaction between Qt and PLA was verified through spectroscopic and calorimetric methods. Delayed diffusion and stronger interaction in PLA-Qt caused the sustained delivery of Qt from the polymer matrix. In vitro cytotoxicity study indicate the killing of ∼ 50% breast cancer cells in two days at 100 μg/ml of drug concentration while the ∼ 40% destruction of cells require 5 days for PLA-Qt (46 ± 6 nm; 20mg/ml of PLA). Thus our results propose anticancer efficacy of PLA-Qt nanoparticles in terms of its sustained release kinetics revealing novel vehicle for the treatment of cancer. Copyright © 2015 Elsevier B.V. All rights reserved.
Magnetic levitation of condensed hydrogen
NASA Technical Reports Server (NTRS)
Paine, C. G.; Seidel, G. M.
1991-01-01
Liquid and solid molecular hydrogen has been levitated using a pair of small superconducting solenoids. The hydrogen samples, up to 3 mm in dimension, were trapped in a magnetic potential having either a discrete minimum or a minimum in the form of a ring 1 cm in diameter. The hydrogen could be moved about in the magnetic trap by applying an electric field.
NASA Astrophysics Data System (ADS)
Bhalla, Amneet Pal Singh; Johansen, Hans; Graves, Dan; Martin, Dan; Colella, Phillip; Applied Numerical Algorithms Group Team
2017-11-01
We present a consistent cell-averaged discretization for incompressible Navier-Stokes equations on complex domains using embedded boundaries. The embedded boundary is allowed to freely cut the locally-refined background Cartesian grid. Implicit-function representation is used for the embedded boundary, which allows us to convert the required geometric moments in the Taylor series expansion (upto arbitrary order) of polynomials into an algebraic problem in lower dimensions. The computed geometric moments are then used to construct stencils for various operators like the Laplacian, divergence, gradient, etc., by solving a least-squares system locally. We also construct the inter-level data-transfer operators like prolongation and restriction for multi grid solvers using the same least-squares system approach. This allows us to retain high-order of accuracy near coarse-fine interface and near embedded boundaries. Canonical problems like Taylor-Green vortex flow and flow past bluff bodies will be presented to demonstrate the proposed method. U.S. Department of Energy, Office of Science, ASCR (Award Number DE-AC02-05CH11231).
Diffractive element in extreme-UV lithography condenser
Sweatt, William C.; Ray-Chaudhuri, Avijit
2001-01-01
Condensers having a mirror with a diffraction grating in projection lithography using extreme ultra-violet significantly enhances critical dimension control. The diffraction grating has the effect of smoothing the illumination at the camera's entrance pupil with minimum light loss. Modeling suggests that critical dimension control for 100 nm features can be improved from 3 nm to less than about 0.5 nm.
Diffractive element in extreme-UV lithography condenser
Sweatt, William C.; Ray-Chaudhurl, Avijit K.
2000-01-01
Condensers having a mirror with a diffraction grating in projection lithography using extreme ultra-violet significantly enhances critical dimension control. The diffraction grating has the effect of smoothing the illumination at the camera's entrance pupil with minimum light loss. Modeling suggests that critical dimension control for 100 nm features can be improved from 3 nm to less than about 0.5 nm.
Local metric dimension of circulant graph c i r c (n :1 ,2 ,…,n/+1 2 )
NASA Astrophysics Data System (ADS)
Rimadhany, Ruzika; Darmaji
2017-08-01
Let G be a connected graph with two vertices u and v. The distance between u and v, denoted by d(u, v), is defined as length of the shortest path from u to v in G. For an ordered set W = {w1, w2, w3, … , wk} of k distinct vertices in a nontrivial connected graph G, the representation of a vertex v of V(G) respect to W is r(v|W) = (d(v, w1), d(v, w2), … , d(v, wk)). The set W is a resolving set of G if r(v|W) for each vertex v ∈ V(G) is distinct. A resolving set of minimum cardinality is a metric dimension and denoted by dim(G). The set W is a local resolving set of G if r(v|W) for every two adjacent vertices of V(G) is distinct. The minimum cardinality of local resolving set of G is a local metric dimension and denoted by ldim(G). In this research, we determine local metric dimension of circulant graph c i r c (n :1 ,2 ,3 ,…,n/+1 2 ) .
Nano sand filter with functionalized nanoparticles embedded in anodic aluminum oxide templates
Phuong, NguyenThi; Andisetiawan, Anugrah; Van Lam, Do; Kim, Jeong Hwan; Choi, Doo-Sun; Whang, Kyung-Hyun; Nham, Jeasun; Lee, Yun Jung; Yoo, Yeong-Eun; Yoon, Jae Sung
2016-01-01
Since the ancient Egyptians had used sand as filter media for water purification, its principle has been inherited through generations and it is still being used now in industries. The sand filter consists of sand literally, and the voids within the sand bed are the pores for filtration. Here we present a filtration principle using nanoparticles, so that the voids between the nanoparticles can be considered as effective pores in nanoscale dimension. Anodic aluminum oxide (AAO) membrane has been used as the working template, and the nanoparticles have been injected and embedded within the pores of the AAO template. Nanoparticles with multiple sizes have been used in order to obtain smaller voids. Moreover, the nanoparticles have been functionalized, or electrically charged, with arginine/phenylalanine (RF) peptide group. In this way, filtration performance for charged particles or molecules, such as methylene blue, has been enhanced. Consequently, this study is expected to provide a new principle for fabrication of nano voids, or nano pores, and for filtration in nanoscale dimension. PMID:27876886
Nano sand filter with functionalized nanoparticles embedded in anodic aluminum oxide templates.
Phuong, NguyenThi; Andisetiawan, Anugrah; Van Lam, Do; Kim, Jeong Hwan; Choi, Doo-Sun; Whang, Kyung-Hyun; Nham, Jeasun; Lee, Yun Jung; Yoo, Yeong-Eun; Yoon, Jae Sung
2016-11-23
Since the ancient Egyptians had used sand as filter media for water purification, its principle has been inherited through generations and it is still being used now in industries. The sand filter consists of sand literally, and the voids within the sand bed are the pores for filtration. Here we present a filtration principle using nanoparticles, so that the voids between the nanoparticles can be considered as effective pores in nanoscale dimension. Anodic aluminum oxide (AAO) membrane has been used as the working template, and the nanoparticles have been injected and embedded within the pores of the AAO template. Nanoparticles with multiple sizes have been used in order to obtain smaller voids. Moreover, the nanoparticles have been functionalized, or electrically charged, with arginine/phenylalanine (RF) peptide group. In this way, filtration performance for charged particles or molecules, such as methylene blue, has been enhanced. Consequently, this study is expected to provide a new principle for fabrication of nano voids, or nano pores, and for filtration in nanoscale dimension.
Nano sand filter with functionalized nanoparticles embedded in anodic aluminum oxide templates
NASA Astrophysics Data System (ADS)
Phuong, Nguyenthi; Andisetiawan, Anugrah; van Lam, Do; Kim, Jeong Hwan; Choi, Doo-Sun; Whang, Kyung-Hyun; Nham, Jeasun; Lee, Yun Jung; Yoo, Yeong-Eun; Yoon, Jae Sung
2016-11-01
Since the ancient Egyptians had used sand as filter media for water purification, its principle has been inherited through generations and it is still being used now in industries. The sand filter consists of sand literally, and the voids within the sand bed are the pores for filtration. Here we present a filtration principle using nanoparticles, so that the voids between the nanoparticles can be considered as effective pores in nanoscale dimension. Anodic aluminum oxide (AAO) membrane has been used as the working template, and the nanoparticles have been injected and embedded within the pores of the AAO template. Nanoparticles with multiple sizes have been used in order to obtain smaller voids. Moreover, the nanoparticles have been functionalized, or electrically charged, with arginine/phenylalanine (RF) peptide group. In this way, filtration performance for charged particles or molecules, such as methylene blue, has been enhanced. Consequently, this study is expected to provide a new principle for fabrication of nano voids, or nano pores, and for filtration in nanoscale dimension.
Correlation Dimension Estimates of Global and Local Temperature Data.
NASA Astrophysics Data System (ADS)
Wang, Qiang
1995-11-01
The author has attempted to detect the presence of low-dimensional deterministic chaos in temperature data by estimating the correlation dimension with the Hill estimate that has been recently developed by Mikosch and Wang. There is no convincing evidence of low dimensionality with either global dataset (Southern Hemisphere monthly average temperatures from 1858 to 1984) or local temperature dataset (daily minimums at Auckland, New Zealand). Any apparent reduction in the dimension estimates appears to be due large1y, if not entirely, to effects of statistical bias, but neither is it a purely random stochastic process. The dimension of the climatic attractor may be significantly larger than 10.
Unbounded Violations of Bipartite Bell Inequalities via Operator Space Theory
NASA Astrophysics Data System (ADS)
Junge, M.; Palazuelos, C.; Pérez-García, D.; Villanueva, I.; Wolf, M. M.
2010-12-01
In this work we show that bipartite quantum states with local Hilbert space dimension n can violate a Bell inequality by a factor of order {Ω left(sqrt{n}/log^2n right)} when observables with n possible outcomes are used. A central tool in the analysis is a close relation between this problem and operator space theory and, in particular, the very recent noncommutative L p embedding theory. As a consequence of this result, we obtain better Hilbert space dimension witnesses and quantum violations of Bell inequalities with better resistance to noise.
Three, Two, One ... Blast Off!
ERIC Educational Resources Information Center
Hawkins, Susan; Rogers, Meredith Park
2014-01-01
This lesson addresses the three dimensions of science learning as laid out in the "Next Generation Science Standards"--science and engineering process skills, crosscutting concepts, and disciplinary core ideas--in addition to embedding practical exposure to NOS tenets in an inquiry-based activity. In addition to the efficiency component,…
Rationality and Belief in Learning Mathematics
ERIC Educational Resources Information Center
Brown, Tony
2016-01-01
This paper argues that rationality and belief are mutually formative dimensions of school mathematics, where each term is more politically embedded than often depicted in the field of mathematics education research. School mathematics then presents not so much rational mathematical thought distorted by irrational beliefs but rather a particular…
Brane world in non-Riemannian geometry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maier, R.; Falciano, F. T.
2011-03-15
We carefully investigate the modified Einstein's field equation in a 4-dimensional (3-brane) arbitrary manifold embedded in a 5-dimensional non-Riemannian bulk spacetime with a noncompact extra dimension. In this context the Israel-Darmois matching conditions are extended assuming that the torsion in the bulk is continuous. The discontinuity in the torsion first derivatives are related to the matter distribution through the field equation. In addition, we develop a model that describes a flat FLRW model embedded in a 5-dimensional de Sitter or anti-de Sitter, where a 5-dimensional cosmological constant emerges from the torsion.
NASA Astrophysics Data System (ADS)
Huby, Nolwenn; Bigeon, John; Lagneaux, Quentin; Amela-Cortes, Maria; Garreau, Alexandre; Molard, Yann; Fade, Julien; Desert, Anthony; Faulques, Eric; Bêche, Bruno; Duvail, Jean-Luc; Cordier, Stéphane
2016-02-01
Integration of stable emissive entities into organic waveguide with minimum scattering is essential to design efficient optically active devices. Here we present a new class of doped nanocomposite waveguides exploiting 1-nm diameter metallic cluster-based building blocks as red-NIR luminescent dyes embedded in a SU8 polymeric matrix, a reference photoresist for organic photonics. These building blocks are [Mo6Ii8(OOCC2F5)a6]2- cluster anionic units with unique chemical and physical features well suited for optical nanocomposites such as a ligand-promoted dispersibility, a large Stokes shift with a broad absorption window and an emission window in the range 600-900 nm. A whole investigation of the nanocomposite has been first performed. Optical characterizations of Cs2[Mo6Ii8(OOCCnF2n+1)a6]@SU8 nanocomposites thin film and waveguiding structures show their relevance as active layers in integrated structures with a significant increase of the refractive index of 3 × 10-2 when the cluster concentration increases up to 4 wt%, while keeping high values for the transmitted power, as shown for different waveguide dimensions and clusters concentrations. The efficiency of photoluminescence propagation is investigated as a function of clusters concentration in the excitation area for several waveguides dimensions. Attenuation coefficient ranges between 5 and 18 dB/cm, values of the same order of magnitude as those obtained in polymeric waveguide doped with QDs or organic dyes. This original, stable and efficient nanocomposite is promising for downscaling complex nanosources and active waveguides in the visible and NIR range.
[Upper airway morphology in Down Syndrome patients under dexmedetomidine sedation].
Subramanyam, Rajeev; Fleck, Robert; McAuliffe, John; Radhakrishnan, Rupa; Jung, Dorothy; Patino, Mario; Mahmoud, Mohamed
2016-01-01
Children with Down Syndrome are vulnerable to significant upper airway obstruction due to relative macroglossia and dynamic airway collapse. The objective of this study was to compare the upper airway dimensions of children with Down Syndrome and obstructive sleep apnea with normal airway under dexmedetomidine sedation. IRB approval was obtained. In this retrospective study, clinically indicated dynamic sagittal midline magnetic resonance images of the upper airway were obtained under low (1mcg/kg/h) and high (3mcg/kg/h) dose dexmedetomidine. Airway anteroposterior diameters and sectional areas were measured as minimum and maximum dimensions by two independent observers at soft palate (nasopharyngeal airway) and at base of the tongue (retroglossal airway). Minimum anteroposterior diameter and minimum sectional area at nasopharynx and retroglossal airway were significantly reduced in Down Syndrome compared to normal airway at both low and high dose dexmedetomidine. However, there were no significant differences between low and high dose dexmedetomidine in both Down Syndrome and normal airway. The mean apnea hypopnea index in Down Syndrome was 16±11. Under dexmedetomidine sedation, children with Down Syndrome and obstructive sleep apnea when compared to normal airway children show significant reductions in airway dimensions most pronounced at the narrowest points in the nasopharyngeal and retroglossal airways. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.
Upper airway morphology in Down Syndrome patients under dexmedetomidine sedation.
Subramanyam, Rajeev; Fleck, Robert; McAuliffe, John; Radhakrishnan, Rupa; Jung, Dorothy; Patino, Mario; Mahmoud, Mohamed
2016-01-01
Children with Down Syndrome are vulnerable to significant upper airway obstruction due to relative macroglossia and dynamic airway collapse. The objective of this study was to compare the upper airway dimensions of children with Down Syndrome and obstructive sleep apnea with normal airway under dexmedetomidine sedation. IRB approval was obtained. In this retrospective study, clinically indicated dynamic sagittal midline magnetic resonance images of the upper airway were obtained under low (1mcg/kg/h) and high (3mcg/kg/h) dose dexmedetomidine. Airway anteroposterior diameters and sectional areas were measured as minimum and maximum dimensions by two independent observers at soft palate (nasopharyngeal airway) and at base of the tongue (retroglossal airway). Minimum anteroposterior diameter and minimum sectional area at nasopharynx and retroglossal airway were significantly reduced in Down Syndrome compared to normal airway at both low and high dose dexmedetomidine. However, there were no significant differences between low and high dose dexmedetomidine in both Down Syndrome and normal airway. The mean apnea hypopnea index in Down Syndrome was 16±11. Under dexmedetomidine sedation, children with Down Syndrome and obstructive sleep apnea when compared to normal airway children show significant reductions in airway dimensions most pronounced at the narrowest points in the nasopharyngeal and retroglossal airways. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.
a Probabilistic Embedding Clustering Method for Urban Structure Detection
NASA Astrophysics Data System (ADS)
Lin, X.; Li, H.; Zhang, Y.; Gao, L.; Zhao, L.; Deng, M.
2017-09-01
Urban structure detection is a basic task in urban geography. Clustering is a core technology to detect the patterns of urban spatial structure, urban functional region, and so on. In big data era, diverse urban sensing datasets recording information like human behaviour and human social activity, suffer from complexity in high dimension and high noise. And unfortunately, the state-of-the-art clustering methods does not handle the problem with high dimension and high noise issues concurrently. In this paper, a probabilistic embedding clustering method is proposed. Firstly, we come up with a Probabilistic Embedding Model (PEM) to find latent features from high dimensional urban sensing data by "learning" via probabilistic model. By latent features, we could catch essential features hidden in high dimensional data known as patterns; with the probabilistic model, we can also reduce uncertainty caused by high noise. Secondly, through tuning the parameters, our model could discover two kinds of urban structure, the homophily and structural equivalence, which means communities with intensive interaction or in the same roles in urban structure. We evaluated the performance of our model by conducting experiments on real-world data and experiments with real data in Shanghai (China) proved that our method could discover two kinds of urban structure, the homophily and structural equivalence, which means clustering community with intensive interaction or under the same roles in urban space.
Sparse Representation Based Classification with Structure Preserving Dimension Reduction
2014-03-13
dictionary learning [39] used stochastic approximations to update dictionary with a large data set. Laplacian score dictionary ( LSD ) [58], which is based on...vol. 4. 2003. p. 864–7. 47. Shaw B, Jebara T. Structure preserving embedding. In: The 26th annual international conference on machine learning, ICML
Evidencing Learning Outcomes: A Multi-Level, Multi-Dimensional Course Alignment Model
ERIC Educational Resources Information Center
Sridharan, Bhavani; Leitch, Shona; Watty, Kim
2015-01-01
This conceptual framework proposes a multi-level, multi-dimensional course alignment model to implement a contextualised constructive alignment of rubric design that authentically evidences and assesses learning outcomes. By embedding quality control mechanisms at each level for each dimension, this model facilitates the development of an aligned…
Flipped Learning as a Paradigm Shift in Architectural Education
ERIC Educational Resources Information Center
Elrayies, Ghada Mohammad
2017-01-01
The target of Education for Sustainable Development is to make people creative and lifelong learners. Over the past years, architectural education has faced challenges of embedding innovation and creativity into its programs. That calls the graduates to be more skilled in the human dimensions of professional practice. So, architectural education…
What Do Students Want? Making Sense of Student Preferences in Technology-Enhanced Learning
ERIC Educational Resources Information Center
Pechenkina, Ekaterina; Aeschliman, Carol
2017-01-01
This article, with its focus on university students as intended recipients and users of technological innovations in education, explores student preferences across three dimensions of technology-enhanced learning: mode of instruction; communication; and educational technology tools embedded in learning and teaching activities. The article draws on…
Leadership Development: An Examination of Individual and Programmatic Growth
ERIC Educational Resources Information Center
Conner, Jerusha Osberg; Strobel, Karen
2007-01-01
This study focuses on two girls' experiences in one youth leadership organization during a period of 3 years. Relying on an embedded case study design, the authors examine the links between leadership development and programmatic structures and supports. Specifically, the development of leadership capacities are analyzed along three dimensions:…
ERIC Educational Resources Information Center
Blackmore, Jill
2011-01-01
Not until the late 1990s did the rational/emotional binary embedded in mainstream literature on educational leadership and management come under challenge. Now the emotional dimensions of organisational change and leadership are widely recognised in the leadership, organisational change and school improvement literature. However, the dissolution…
Aaker, J L; Benet-Martínez, V; Garolera, J
2001-09-01
This research argues that the meaning embedded in consumption symbols, such as commercial brands, can serve to represent and institutionalize the values and beliefs of a culture. Relying on a combined emic-etic approach, the authors conducted 4 studies to examine how symbolic and expressive attributes associated with commercial brands are structured and how this structure varies across 3 cultures. Studies 1 and 2 revealed a set of "brand personality" dimensions common to both Japan and the United States (Sincerity, Excitement, Competence, and Sophistication), as well as culture-specific Japanese (Peacefulness) and American (Ruggedness) dimensions. Studied 3 and 4, which extended this set of findings to Spain, yielded brand personality dimensions common to both Spain and the United States (Sincerity, Excitement, and Sophistication), plus nonshared Spanish (Passion) and American (Competence and Ruggedness) dimensions. The meaning of these brand personality dimensions is discussed in the context of cross-cultural research on values and affect, globalization issues, and cultural frame shifting.
NASA Astrophysics Data System (ADS)
Wesson, Paul S.
2015-11-01
Recent criticism of higher-dimensional extensions of Einstein's theory is considered. This may have some justification in regard to string theory, but is misguided as applied to five-dimensional (5D) theories with a large extra dimension. Such theories smoothly embed general relativity, ensuring recovery of the latter's observational support. When the embedding of spacetime is carried out in accordance with Campbell's theorem, the resulting 5D theory naturally explains the origin of classical matter and vacuum energy. Also, constraints on the equations of motion near a high-energy surface or membrane in the 5D manifold lead to quantization and quantum uncertainty. These are major returns on the modest investment of one extra dimension. Instead of fruitless bickering about whether it is possible to "see" the fifth dimension, it is suggested that it be treated on par with other concepts of physics, such as time. The main criterion for the acceptance of a fifth dimension (or not) should be its usefulness.
Beacon system based on light-emitting diode sources for runways lighting
NASA Astrophysics Data System (ADS)
Montes, Mario González; Vázquez, Daniel; Fernandez-Balbuena, Antonio A.; Bernabeu, Eusebio
2014-06-01
New aeronautical ground lighting techniques are becoming increasingly important to ensure the safety and reduce the maintenance costs of the plane's tracks. Until recently, tracks had embedded lighting systems whose sources were based on incandescent lamps. But incandescent lamps have several disadvantages: high energy consumption and frequent breakdowns that result in high maintenance costs (lamp average life-time is ˜1500 operating hours) and the lamp's technology has a lack of new lighting functions, such as signal handling and modification. To solve these problems, the industry has developed systems based on light-emitting diode (LED) technology with improved features: (1) LED lighting consumes one tenth the power, (2) it improves preventive maintenance (an LED's lifetime range is between 25,000 and 100,000 hours), and (3) LED lighting technology can be controlled remotely according to the needs of the track configuration. LEDs have been in use for more than three decades, but only recently, around 2002, have they begun to be used as visual aids, representing the greatest potential change for airport lighting since their inception in the 1920s. Currently, embedded LED systems are not being broadly used due to the specific constraints of the rules and regulations of airports (beacon dimensions, power system technology, etc.). The fundamental requirements applied to embedded lighting systems are to be hosted on a volume where the dimensions are usually critical and also to integrate all the essential components for operation. An embedded architecture that meets the lighting regulations for airport runways is presented. The present work is divided into three main tasks: development of an optical system to optimize lighting according to International Civil Aviation Organization, manufacturing prototype, and model validation.
Sun, Cheuk-Kwan; Zhen, Yen-Yi; Leu, Steve; Tsai, Tzu-Hsien; Chang, Li-Teh; Sheu, Jiunn-Jye; Chen, Yung-Lung; Chua, Sarah; Chai, Han-Tan; Lu, Hung-I; Chang, Hsueh-Wen; Lee, Fan-Yen; Yip, Hon-Kan
2014-05-15
This study tested whether adipose-derived mesenchymal stem cells (ADMSC) embedded in platelet-rich fibrin (PRF) scaffold is superior to direct ADMSC implantation in improving left ventricular (LV) performance and reducing LV remodeling in a rat acute myocardial infarction (AMI) model of left anterior descending coronary artery (LAD) ligation. Twenty-eight male adult Sprague Dawley rats equally divided into group 1 [sham control], group 2 (AMI only), group 3 (AMI+direct ADMSC implantation), and group 4 (AMI+PRF-embedded autologous ADMSC) were sacrificed on day 42 after AMI. LV systolic and diastolic dimensions and volumes, and infarct/fibrotic areas were highest in group 2, lowest in group 1 and significantly higher in group 3 than in group 4, whereas LV performance and LV fractional shortening exhibited a reversed pattern (p<0.005). Protein expressions of inflammation (oxidative stress, IL-1β, MMP-9), apoptosis (mitochondrial Bax, cleaved PARP), fibrosis (Smad3, TGF-β), and pressure-overload biomarkers (BNP, MHC-β) displayed a pattern similar to that of LV dimensions, whereas anti-inflammatory (IL-10), anti-apoptotic (Bcl-2), and anti-fibrotic (Smad1/5, BMP-2) indices showed a pattern similar to that of LV performance among the four groups (all p<0.05). Angiogenesis biomarkers at protein (CXCR4, SDF-1α, VEGF), cellular (CD31+, CXCR4+, SDF-1α+), and immunohistochemical (small vessels) levels, and cardiac stem cell markers (C-kit+, Sca-1+) in infarct myocardium were highest in group 4, lowest in group 1, and significantly higher in group 3 than in group 2 (all p<0.005). PRF-embedded ADMSC is superior to direct ADMSC implantation in preserving LV function and attenuating LV remodeling. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
CKM pattern from localized generations in extra dimension
NASA Astrophysics Data System (ADS)
Matti, C.
2006-10-01
We revisit the issue of the quark masses and mixing angles in the framework of large extra dimension. We consider three identical standard model families resulting from higher-dimensional fields localized on different branes embedded in a large extra dimension. Furthermore we use a decaying profile in the bulk different form previous works. With the Higgs field also localized on a different brane, the hierarchy of masses between the families results from their different positions in the extra space. When the left-handed doublet and the right-handed singlets are localized with different couplings on the branes, we found a set of brane locations in one extra dimension which leads to the correct quark masses and mixing angles with the sufficient strength of CP-violation. We see that the decaying profile of the Higgs field plays a crucial role for producing the hierarchies in a rather natural way.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taylor, Margaret; Spurlock, C. Anna; Yang, Hung-Chia
The dual purpose of this project was to contribute to basic knowledge about the interaction between regulation and innovation and to inform the cost and benefit expectations related to technical change which are embedded in the rulemaking process of an important area of national regulation. The area of regulation focused on here is minimum efficiency performance standards (MEPS) for appliances and other energy-using products. Relevant both to U.S. climate policy and energy policy for buildings, MEPS remove certain product models from the market that do not meet specified efficiency thresholds.
A Review on Dimension Reduction
Ma, Yanyuan; Zhu, Liping
2013-01-01
Summary Summarizing the effect of many covariates through a few linear combinations is an effective way of reducing covariate dimension and is the backbone of (sufficient) dimension reduction. Because the replacement of high-dimensional covariates by low-dimensional linear combinations is performed with a minimum assumption on the specific regression form, it enjoys attractive advantages as well as encounters unique challenges in comparison with the variable selection approach. We review the current literature of dimension reduction with an emphasis on the two most popular models, where the dimension reduction affects the conditional distribution and the conditional mean, respectively. We discuss various estimation and inference procedures in different levels of detail, with the intention of focusing on their underneath idea instead of technicalities. We also discuss some unsolved problems in this area for potential future research. PMID:23794782
Gaertner, Maria; Cimalla, Peter; Meissner, Sven; Kuebler, Wolfgang M; Koch, Edmund
2012-07-01
Although several strategies exist for a minimal-invasive treatment of patients with lung failure, the mortality rate of acute respiratory distress syndrome still reaches 30% at minimum. This striking number indicates the necessity of understanding lung dynamics on an alveolar level. To investigate the dynamical behavior on a microscale, we used three-dimensional geometrical and functional imaging to observe tissue parameters including alveolar size and length of embedded elastic fibers during ventilation. We established a combined optical coherence tomography (OCT) and confocal fluorescence microscopy system that is able to monitor the distension of alveolar tissue and elastin fibers simultaneously within three dimensions. The OCT system can laterally resolve a 4.9 μm line pair feature and has an approximately 11 μm full-width-half-maximum axial resolution in air. confocal fluorescence microscopy visualizes molecular properties of the tissue with a resolution of 0.75 μm (laterally), and 5.9 μm (axially) via fluorescence detection of the dye sulforhodamine B specifically binding to elastin. For system evaluation, we used a mouse model in situ to perform lung distension by application of different constant pressure values within the physiological regime. Our method enables the investigation of alveolar dynamics by helping to reveal basic processes emerging during artificial ventilation and breathing.
The justification of studies in genetic epidemiology - political scaling in China Medical City.
Sleeboom-Faulkner, Margaret
2018-04-01
Genetic epidemiology examines the role of genetic factors in determining health and disease in families and in populations to help addressing health problems in a responsible manner. This paper uses a case study of genetic epidemiology in Taizhou, China, to explore ways in which anthropology can contribute to the validation of studies in genetic epidemiology. It does so, first, by identifying potential overgeneralizations of data, often due to mismatching scale and, second, by examining it's embedding in political, historical and local contexts. The example of the longitudinal cohort study in Taizhou illustrates dimensions of such 'political scaling'. Political scaling is a notion used here to refer to the effects of scaling biases in relation to the justification of research in terms of relevance, reach and research ethics. The justification of a project on genetic epidemiology involves presenting a maximum of benefits and a minimum of burden for the population. To facilitate the delineation of political scaling, an analytical distinction between donating and benefiting communities was made using the notions of 'scaling of relevance', 'scaling of reach' and 'scaling of ethics'. Political scaling results at least partly from factors external to research. By situating political scaling in the context of historical, political and local discourses, anthropologists can play a complementary role in genetic epidemiology.
Streamflow Prediction based on Chaos Theory
NASA Astrophysics Data System (ADS)
Li, X.; Wang, X.; Babovic, V. M.
2015-12-01
Chaos theory is a popular method in hydrologic time series prediction. Local model (LM) based on this theory utilizes time-delay embedding to reconstruct the phase-space diagram. For this method, its efficacy is dependent on the embedding parameters, i.e. embedding dimension, time lag, and nearest neighbor number. The optimal estimation of these parameters is thus critical to the application of Local model. However, these embedding parameters are conventionally estimated using Average Mutual Information (AMI) and False Nearest Neighbors (FNN) separately. This may leads to local optimization and thus has limitation to its prediction accuracy. Considering about these limitation, this paper applies a local model combined with simulated annealing (SA) to find the global optimization of embedding parameters. It is also compared with another global optimization approach of Genetic Algorithm (GA). These proposed hybrid methods are applied in daily and monthly streamflow time series for examination. The results show that global optimization can contribute to the local model to provide more accurate prediction results compared with local optimization. The LM combined with SA shows more advantages in terms of its computational efficiency. The proposed scheme here can also be applied to other fields such as prediction of hydro-climatic time series, error correction, etc.
A modeling framework for life history-based conservation planning
Eileen S. Burns; Sandor F. Toth; Robert G. Haight
2013-01-01
Reserve site selection models can be enhanced by including habitat conditions that populations need for food, shelter, and reproduction. We present a new population protection function that determines whether minimum areas of land with desired habitat features are present within the desired spatial conditions in the protected sites. Embedding the protection function as...
Dependence of the quantum speed limit on system size and control complexity
NASA Astrophysics Data System (ADS)
Lee, Juneseo; Arenz, Christian; Rabitz, Herschel; Russell, Benjamin
2018-06-01
We extend the work in 2017 New J. Phys. 19 103015 by deriving a lower bound for the minimum time necessary to implement a unitary transformation on a generic, closed quantum system with an arbitrary number of classical control fields. This bound is explicitly analyzed for a specific N-level system similar to those used to represent simple models of an atom, or the first excitation sector of a Heisenberg spin chain, both of which are of interest in quantum control for quantum computation. Specifically, it is shown that the resultant bound depends on the dimension of the system, and on the number of controls used to implement a specific target unitary operation. The value of the bound determined numerically, and an estimate of the true minimum gate time are systematically compared for a range of system dimension and number of controls; special attention is drawn to the relationship between these two variables. It is seen that the bound captures the scaling of the minimum time well for the systems studied, and quantitatively is correct in the order of magnitude.
Vision and the dimensions of nerve fibers.
Wade, Nicholas J
2005-12-01
Vision provided the obvious source of determining the dimensions of nerve fibers when suitable achromatic microscopes were directed at neural tissue in the 1830s. The earlier microscopes of Hooke and Leeuwenhoek were unable to resolve such small structures adequately. However, it was not Hooke's microscope that led to an estimate of the dimensions of nerve fibers, but his experiments on the limits of visual resolution; he determined that a separation of one minute of arc was the minimum that could normally be seen. Descartes had earlier speculated that the retina consisted of the ends of fibers of the optic nerve, and that their size defined the limits of what could be seen. Estimates of the diameters of nerve fibers were made on the basis of human visual acuity by Porterfield in 1738; he calculated the diameters of nerve fibers in the retina as one 7,200th part of an inch (0.0035 mm), based on the resolution of one minute as the minimum visible. In the same year, Jurin questioned the reliability of such estimates because of variations in visual resolution with different stimuli.
Antibiotic loading and release studies of LSMO nanoparticles embedded in an acrylic polymer
NASA Astrophysics Data System (ADS)
Biswas, Sonali; Keshri, Sunita; Goswami, Sudipta; Isaac, Jinu; Ganguly, Swastika; Perov, Nikolai
2016-12-01
In this paper, we present the drug loading and release works of ? (LSMO) manganite nanoparticles (NPs). The LSMO NPs, grown using the sol-gel method, were embedded in an acrylic interpenetrating polymer network to make the sample applicable for biomedical purposes. The results of scanning electron microscopy showed that these NPs were well dispersed in the polymer. The grain size of these NPs lies in the range of 25-45 nm, as confirmed by transmission electron microscopy. The measurements of DC magnetization and hysteresis loops reveal that the basic magnetic behaviour of the LSMO NPs remained almost unaltered even after embedding in polymer, but with lower saturation value of magnetization. The drug loading and release studies of the grown sample were carried out using an antibiotic, ciprofloxacin. The minimum inhibitory effect of the sample loaded with this drug has exhibited high activity against different strains of bacteria, comparable to the pure ciprofloxacin.
Iliesiu, Luca; Kos, Filip; Poland, David; ...
2016-03-17
We study the conformal bootstrap for a 4-point function of fermions in 3D. We first introduce an embedding formalism for 3D spinors and compute the conformal blocks appearing in fermion 4-point functions. Using these results, we find general bounds on the dimensions of operators appearing in the ψ × ψ OPE, and also on the central charge C T. We observe features in our bounds that coincide with scaling dimensions in the GrossNeveu models at large N. Finally, we also speculate that other features could coincide with a fermionic CFT containing no relevant scalar operators.
Spiritual Well-Being and Alcoholism: A Cross-Cultural View.
ERIC Educational Resources Information Center
Miller, Geraldine A.; Russo, Thomas J.
Although much of traditional psychology assumes that a spiritual orientation is largely a matter of choice, it is contended here that such choices are embedded in the rich fabric of the cultural framework. This study explores a quantitative and qualitative contrast between Caucasian and Native American alcoholics on dimensions of spiritual…
CyGaMEs Selene Player Log Dataset: Gameplay Assessment, Flow Dimensions and Non-Gameplay Assessments
ERIC Educational Resources Information Center
Reese, Debbie Denise
2015-01-01
The "Selene: A Lunar Construction GaME" instructional video game is a robust research environment (institutional review board approved) for investigating learning, affect, and the CyGaMEs Metaphorics approach to instructional video game design, embedded assessment, and informatics analysis and reporting. CyGaMEs applies analogical…
Education for Rural Development: Embedding Rural Dimensions in Initial Teacher Preparation
ERIC Educational Resources Information Center
Masinire, Alfred; Maringe, Felix; Nkambule, Thabisile
2014-01-01
In South Africa, rural education and development are issues of social justice, especially in places that were previously established as homelands. This article presents some of the tensions that are inherent in the conceptions of rurality, rural education and the possibility of sustainable rural education and development. We propose the notion of…
A small, 1400 K, reactor for Brayton space power systems.
NASA Technical Reports Server (NTRS)
Lantz, E.; Mayo, W.
1972-01-01
An investigation was conducted to determine minimum dimensions and minimum weight obtainable in a design for a reactor using uranium-233 nitride or plutonium-239 nitride as fuel. Such a reactor had been considered by Krasner et al. (1971). Present space power status is discussed, together with questions of reactor design and power distribution in the reactor. The characteristics of various reactor types are compared, giving attention also to a zirconium hydride reactor.
NASA Technical Reports Server (NTRS)
Olson, Roland E; Land, Norman S
1949-01-01
Tests were made to fill partly the need for information on the effect of afterbody dimensions on the hydrodynamic stability of a flying boat in smooth water. The dimensions investigated were depth of step, angle of afterbody keel, and length of afterbody. An analysis of the data showed that as either the afterbody length or keel angle was increased an accompanying increase in depth of step was required in order to maintain adequate landing stability. The landing-tests results have been reduced to an empirical formula giving the minimum depth of step in terms of afterbody length and keel angle. This formula is compared with results from other tank tests, and the correlation is fairly good. The formula thus becomes of use in preliminary design.
A local crack-tracking strategy to model three-dimensional crack propagation with embedded methods
DOE Office of Scientific and Technical Information (OSTI.GOV)
Annavarapu, Chandrasekhar; Settgast, Randolph R.; Vitali, Efrem
We develop a local, implicit crack tracking approach to propagate embedded failure surfaces in three-dimensions. We build on the global crack-tracking strategy of Oliver et al. (Int J. Numer. Anal. Meth. Geomech., 2004; 28:609–632) that tracks all potential failure surfaces in a problem at once by solving a Laplace equation with anisotropic conductivity. We discuss important modifications to this algorithm with a particular emphasis on the effect of the Dirichlet boundary conditions for the Laplace equation on the resultant crack path. Algorithmic and implementational details of the proposed method are provided. Finally, several three-dimensional benchmark problems are studied and resultsmore » are compared with available literature. Lastly, the results indicate that the proposed method addresses pathological cases, exhibits better behavior in the presence of closely interacting fractures, and provides a viable strategy to robustly evolve embedded failure surfaces in 3D.« less
A local crack-tracking strategy to model three-dimensional crack propagation with embedded methods
Annavarapu, Chandrasekhar; Settgast, Randolph R.; Vitali, Efrem; ...
2016-09-29
We develop a local, implicit crack tracking approach to propagate embedded failure surfaces in three-dimensions. We build on the global crack-tracking strategy of Oliver et al. (Int J. Numer. Anal. Meth. Geomech., 2004; 28:609–632) that tracks all potential failure surfaces in a problem at once by solving a Laplace equation with anisotropic conductivity. We discuss important modifications to this algorithm with a particular emphasis on the effect of the Dirichlet boundary conditions for the Laplace equation on the resultant crack path. Algorithmic and implementational details of the proposed method are provided. Finally, several three-dimensional benchmark problems are studied and resultsmore » are compared with available literature. Lastly, the results indicate that the proposed method addresses pathological cases, exhibits better behavior in the presence of closely interacting fractures, and provides a viable strategy to robustly evolve embedded failure surfaces in 3D.« less
Enhanced emission of nile red fluorescent nanoparticles embedded in hybrid sol-gel glasses.
Ferrer, Maria L; del Monte, Francisco
2005-01-13
Highly fluorescent Nile Red (NR) nanoparticles embedded in a hybrid sol-gel glass are reported. The crystallite growth within the confined system created by the porous hybrid matrix results in NR nanoparticles of averaged dimensions below 36 nm. The preparation process allows for the control of both the conformation adopted by single NR molecules prior to aggregation (e.g., near planar) and the configuration of the aggregates (e.g., oblique with phi < 54.7 degrees) prior to their assembly in the supramolecular architecture which ultimately forms the nanoparticles. The full preservation of the fluorescent configuration of the aggregates in the nanoparticles is confirmed through the application of the exciton theory, and it is responsible for the significant increase of the fluorescence emission intensity (e.g., up to 525- and 70-fold as compared to that obtained for single NR molecules embedded in pure and hybrid silica glasses, respectively).
NASA Astrophysics Data System (ADS)
Ghosh, Avirup; Mishra, Rohit
2018-04-01
The change in holographic entanglement entropy (HEE) for small fluctuations about pure anti-de Sitter (AdS) is obtained by a perturbative expansion of the area functional in terms of the change in the bulk metric and the embedded extremal surface. However it is known that change in the embedding appears at second order or higher. It was shown that these changes in the embedding can be calculated in the 2 +1 dimensional case by solving a "generalized geodesic deviation equation." We generalize this result to arbitrary dimensions by deriving an inhomogeneous form of the Jacobi equation for minimal surfaces. The solutions of this equation map a minimal surface in a given space time to a minimal surface in a space time which is a perturbation over the initial space time. Using this we perturbatively calculate the changes in HEE up to second order for boosted black brane like perturbations over AdS4.
The Use of Color as a Third Dimension on Maps
NASA Astrophysics Data System (ADS)
Cid, X.; Lopez, R.; Lazarus, S.
2007-12-01
As experts, we are trained to understand color schemes used in visualizations in our respective scientific fields. As experts we also forget how complicated graphics can be when viewed for the first time. Previous studies have shown that three-dimensional diagrams can produce a cognitive overload when rendered on a two-dimensional surface, so the same might apply to graphics that use color as a third dimension. This study was conducted to investigate the use of color as a third dimension. We looked at the use of color as a scale height on a basic topographic map, as well as the use of color as temperature. Fifty-four undergraduates from two different physics courses and REU programs during the spring and summer semesters in 2007 were given surveys regarding the use of color. Of these 54 students, eight students were chosen to participate in interviews designed to investigate, in more detail, the responses provided by the students in the hopes to discover where confusions occur. It was found that students have an embedded color scheme for temperatures of red representing hot and blue representing cold as a product of societal influences, which was expected, but there was no embedded color scheme when color was applied to height. We found that students did not have a preference when viewing a topographic map with different color schemes, but did prefer the color scheme of the figure that they viewed first. We observed that the students did have an embedded notion of what the topographic figure was representing, and tried to fit the color scheme shown to match their idea. During the interviews we also found that even the slightest deviations from a specific color scheme gives rise to confusion. These results, therefore, show the importance of detail consistency when using visualizations in a lecture where the population is composed of novices.
Simulation of an ankle rehabilitation system based on scotch- yoke mechanism
NASA Astrophysics Data System (ADS)
Racu (Cazacu, C. M.; Doroftei, I.; Plesu, Ghe; Doroftei, I. A.
2016-08-01
Due to injuries that occur on the ankle joint, everyday all around the world, more and more rehabilitation devices have been developed in recent years. The prices for ankle rehabilitation systems are still high, thus we developed a new device that we indented to be low cost and easy to manufacture. A model of an ankle rehabilitation device is presented in this paper. The device has two degrees of freedom, for flexion-extension and inversion-eversion move, and will ensure functionality with minimum dimensions. For the 3D model that we design, the dimensions are taken so that the proposed system will ensure functionality but also have a small dimensions and low mass, considering the physiological dimensions of the foot and lower leg.
NASA Astrophysics Data System (ADS)
Darmon, David
2018-03-01
In the absence of mechanistic or phenomenological models of real-world systems, data-driven models become necessary. The discovery of various embedding theorems in the 1980s and 1990s motivated a powerful set of tools for analyzing deterministic dynamical systems via delay-coordinate embeddings of observations of their component states. However, in many branches of science, the condition of operational determinism is not satisfied, and stochastic models must be brought to bear. For such stochastic models, the tool set developed for delay-coordinate embedding is no longer appropriate, and a new toolkit must be developed. We present an information-theoretic criterion, the negative log-predictive likelihood, for selecting the embedding dimension for a predictively optimal data-driven model of a stochastic dynamical system. We develop a nonparametric estimator for the negative log-predictive likelihood and compare its performance to a recently proposed criterion based on active information storage. Finally, we show how the output of the model selection procedure can be used to compare candidate predictors for a stochastic system to an information-theoretic lower bound.
Contribution to the optimal shape design of two-dimensional internal flows with embedded shocks
NASA Technical Reports Server (NTRS)
Iollo, Angelo; Salas, Manuel D.
1995-01-01
We explore the practicability of optimal shape design for flows modeled by the Euler equations. We define a functional whose minimum represents the optimality condition. The gradient of the functional with respect to the geometry is calculated with the Lagrange multipliers, which are determined by solving a co-state equation. The optimization problem is then examined by comparing the performance of several gradient-based optimization algorithms. In this formulation, the flow field can be computed to an arbitrary order of accuracy. Finally, some results for internal flows with embedded shocks are presented, including a case for which the solution to the inverse problem does not belong to the design space.
Exploring multicollinearity using a random matrix theory approach.
Feher, Kristen; Whelan, James; Müller, Samuel
2012-01-01
Clustering of gene expression data is often done with the latent aim of dimension reduction, by finding groups of genes that have a common response to potentially unknown stimuli. However, what is poorly understood to date is the behaviour of a low dimensional signal embedded in high dimensions. This paper introduces a multicollinear model which is based on random matrix theory results, and shows potential for the characterisation of a gene cluster's correlation matrix. This model projects a one dimensional signal into many dimensions and is based on the spiked covariance model, but rather characterises the behaviour of the corresponding correlation matrix. The eigenspectrum of the correlation matrix is empirically examined by simulation, under the addition of noise to the original signal. The simulation results are then used to propose a dimension estimation procedure of clusters from data. Moreover, the simulation results warn against considering pairwise correlations in isolation, as the model provides a mechanism whereby a pair of genes with `low' correlation may simply be due to the interaction of high dimension and noise. Instead, collective information about all the variables is given by the eigenspectrum.
ERIC Educational Resources Information Center
Liou, Wei-Kai; Bhagat, Kaushal Kumar; Chang, Chun-Yen
2016-01-01
The present study compares the highly interactive cloud-classroom (HIC) system with traditional methods of teaching materials science that utilize crystal structure picture or real crystal structure model, in order to examine its learning effectiveness across three dimensions: knowledge, comprehension and application. The aim of this study was to…
ERIC Educational Resources Information Center
Brigham, Susan M.; Baillie Abidi, Catherine; Zhang, Yuhui
2018-01-01
Migration is a gendered phenomenon, embedded within patriarchal structures and social relations that extend beyond State borders. We draw on a transnational feminist framework to explore the gendered dimensions of young refugee and immigrant women's migration and learning experiences. Ten women were involved in a participatory photography research…
Integrating Databases with Maps: The Delivery of Cultural Data through TimeMap.
ERIC Educational Resources Information Center
Johnson, Ian
TimeMap is a unique integration of database management, metadata and interactive maps, designed to contextualise and deliver cultural data through maps. TimeMap extends conventional maps with the time dimension, creating and animating maps "on-the-fly"; delivers them as a kiosk application or embedded in Web pages; links flexibly to…
BEARCLAW: Boundary Embedded Adaptive Refinement Conservation LAW package
NASA Astrophysics Data System (ADS)
Mitran, Sorin
2011-04-01
The BEARCLAW package is a multidimensional, Eulerian AMR-capable computational code written in Fortran to solve hyperbolic systems for astrophysical applications. It is part of AstroBEAR, a hydrodynamic & magnetohydrodynamic code environment designed for a variety of astrophysical applications which allows simulations in 2, 2.5 (i.e., cylindrical), and 3 dimensions, in either cartesian or curvilinear coordinates.
On the star partition dimension of comb product of cycle and path
NASA Astrophysics Data System (ADS)
Alfarisi, Ridho; Darmaji
2017-08-01
Let G = (V, E) be a connected graphs with vertex set V(G), edge set E(G) and S ⊆ V(G). Given an ordered partition Π = {S1, S2, S3, …, Sk} of the vertex set V of G, the representation of a vertex v ∈ V with respect to Π is the vector r(v|Π) = (d(v, S1), d(v, S2), …, d(v, Sk)), where d(v, Sk) represents the distance between the vertex v and the set Sk and d(v, Sk) = min{d(v, x)|x ∈ Sk }. A partition Π of V(G) is a resolving partition if different vertices of G have distinct representations, i.e., for every pair of vertices u, v ∈ V(G), r(u|Π) ≠ r(v|Π). The minimum k of Π resolving partition is a partition dimension of G, denoted by pd(G). The resolving partition Π = {S1, S2, S3, …, Sk } is called a star resolving partition for G if it is a resolving partition and each subgraph induced by Si, 1 ≤ i ≤ k, is a star. The minimum k for which there exists a star resolving partition of V(G) is the star partition dimension of G, denoted by spd(G). Finding the star partition dimension of G is classified to be a NP-Hard problem. In this paper, we will show that the partition dimension of comb product of cycle and path namely Cm⊳Pn and Pn⊳Cm for n ≥ 2 and m ≥ 3.
States that are far from being stabilizer states
NASA Astrophysics Data System (ADS)
Andersson, David; Bengtsson, Ingemar; Blanchfield, Kate; Bui Dang, Hoan
2015-08-01
Stabilizer states are eigenvectors of maximal commuting sets of operators in a finite Heisenberg group. States that are far from being stabilizer states include magic states in quantum computation, MUB-balanced states, and SIC vectors. In prime dimensions the latter two fall under the umbrella of minimum uncertainty states (MUSs) in the sense of Wootters and Sussman. We study the correlation between two ways in which the notion of ‘far from being a stabilizer state’ can be quantified. Two theorems valid for all prime dimensions are given, as well as detailed results for low dimensions. In dimension 7 we identify the MUB-balanced states as being antipodal to the SIC vectors within the set of MUS, in a sense that we make definite. In dimension 4 we show that the states that come closest to being MUS with respect to all of the six stabilizer MUBs are the fiducial vectors for Alltop MUBs.
1992-01-01
VM and the correlation entropy K,(M) versus the embedding dimension M for both the linear and non-linear signals. Crosses refer to the linear signal...mensions, leading to a correlation dimension v=2.7. A similar structure was observed bv Voges et al. [461 in the analysis of the X-ray variability of...0 + 7 1j, and its recurrence plots often indicates whether a where A 0 = 10 and 71, is uniformly random dis- meaningful correlation integral analysis
NASA Astrophysics Data System (ADS)
Buyadzhi, V. V.; Glushkov, A. V.; Khetselius, O. Yu; Ternovsky, V. B.; Serga, I. N.; Bykowszczenko, N.
2017-10-01
Results of analysis and modelling the air pollutant (dioxide of nitrogen) concentration temporal dynamics in atmosphere of the industrial city Odessa are presented for the first time and based on computing by nonlinear methods of the chaos and dynamical systems theories. A chaotic behaviour is discovered and investigated. To reconstruct the corresponding strange chaotic attractor, the time delay and embedding dimension are computed. The former is determined by the methods of autocorrelation function and average mutual information, and the latter is calculated by means of correlation dimension method and algorithm of false nearest neighbours. It is shown that low-dimensional chaos exists in the nitrogen dioxide concentration time series under investigation. Further, the Lyapunov’s exponents spectrum, Kaplan-Yorke dimension and Kolmogorov entropy are computed.
Powder and particulate production of metallic alloys
NASA Technical Reports Server (NTRS)
Grant, N. J.
1982-01-01
Developments of particulate metallurgy of alloyed materials where the final products is a fully dense body are discussed. Particulates are defined as powders, flakes, foils, silvers, ribbons and strip. Because rapid solidification is an important factor in particulate metallurgy, all of the particulates must have at least one dimension which is very fine, sometimes as fine as 10 to 50 microns, but move typically up to several hundred microns, provided that the dimension permits a minimum solidification rate of at least 100 K/s.
Ravangard, Ramin; Sajjadnia, Zahra; Jafari, Abdosaleh; Shahsavan, Najme; Bahmaie, Jamshid; Bahadori, Mohammadkarim
2014-01-01
In order to achieve success in today’s competitive world, organizations should adapt to environmental changes. On the other hand, managers should have a set of values and ethical guidelines for their administrative and organizational functions. This study aimed to investigate the association between work ethics and attitudes towards organizational changes among the administrative, financial and support employees of general teaching hospitals affiliated to Shiraz University of Medical Sciences. This was an applied, cross-sectional and descriptive-analytic study conducted in 2013. A sample of 124 employees was selected using stratified sampling proportional to size and simple random sampling methods. Data were collected using 2 questionnaires measuring the dimensions of employees' work ethics (four dimensions) and attitudes towards organizational changes (three dimensions). The collected data were analyzed using SPSS 18.0 and statistical tests, including ANOVA, independent samples t-test, and Pearson’s correlation coefficient. A P < 0.05 was considered statistically significant. The maximum and minimum score of work ethic dimensions were related to being cooperative (4.60 ± 0.38) and dependable (4.29 ± 0.39) respectively. On the other hand, the maximum and minimum score of attitudes towards the various dimensions of organizational changes were related to the behavioral (3.83 ± 0.70) and the affective (3.55 ± 0.88) dimensions respectively. Furthermore, there was a significant relationship between the work ethics and education levels of the employees in this study (P = 0.003). Also, among work s dimensions, only being considerate had a significant association with attitudes towards organizational changes (P = 0.014) and their cognitive dimension (P = 0.005). To improve employees' work ethics and attitudes towards organizational changes, the following suggestions can be offered: training hospitals managers in participative management style and its application, as well as the importance of meeting the employees' needs and expectations based on their characteristics; familiarizing employees with the Islamic work ethic; educating employees on the importance of being considerate towards their colleagues and subordinates in the workplace, and reinforcing this desirable quality; and finally, clarifying the need for changes in the organization for all employees. PMID:25512831
Maintaining the Balance Between Manpower, Skill Levels, and PERSTEMPO
2006-01-01
requirement processes. Models and tools that integrate these dimensions would help crys- tallize issues, identify embedded assumptions , and surface...problems will change if the planning assumptions are incorrect or if the other systems are incapable of making the nec- essary adjustments. Static...Carrillo, Background and Theory Behind the Compensations, Accessions, and Personnel ( CAPM ) Model, Santa Monica, Calif.: RAND Corporation, MR-1667
ERIC Educational Resources Information Center
Yamacli, Rusen; Ozen, Aysegul; Tokman, Leyla Yekdane
2005-01-01
In architectural design education, the main objective is to help students, especially first-year students, improve their design ideas, creativity, perception of three dimensions and ways of expressing them. Thus, as an embedded concept in architecture, art has been emphasized here as a design method. In other words, the necessary help to enable…
Variable input observer for structural health monitoring of high-rate systems
NASA Astrophysics Data System (ADS)
Hong, Jonathan; Laflamme, Simon; Cao, Liang; Dodson, Jacob
2017-02-01
The development of high-rate structural health monitoring methods is intended to provide damage detection on timescales of 10 µs -10ms where speed of detection is critical to maintain structural integrity. Here, a novel Variable Input Observer (VIO) coupled with an adaptive observer is proposed as a potential solution for complex high-rate problems. The VIO is designed to adapt its input space based on real-time identification of the system's essential dynamics. By selecting appropriate time-delayed coordinates defined by both a time delay and an embedding dimension, the proper input space is chosen which allows more accurate estimations of the current state and a reduction of the convergence rate. The optimal time-delay is estimated based on mutual information, and the embedding dimension is based on false nearest neighbors. A simulation of the VIO is conducted on a two degree-of-freedom system with simulated damage. Results are compared with an adaptive Luenberger observer, a fixed time-delay observer, and a Kalman Filter. Under its preliminary design, the VIO converges significantly faster than the Luenberger and fixed observer. It performed similarly to the Kalman Filter in terms of convergence, but with greater accuracy.
Direct synthesis of antimicrobial coatings based on tailored bi-elemental nanoparticles
NASA Astrophysics Data System (ADS)
Benetti, Giulio; Cavaliere, Emanuele; Canteri, Adalberto; Landini, Giulia; Rossolini, Gian Maria; Pallecchi, Lucia; Chiodi, Mirco; Van Bael, Margriet J.; Winckelmans, Naomi; Bals, Sara; Gavioli, Luca
2017-03-01
Ultrathin coatings based on bi-elemental nanoparticles (NPs) are very promising to limit the surface-related spread of bacterial pathogens, particularly in nosocomial environments. However, tailoring the synthesis, composition, adhesion to substrate, and antimicrobial spectrum of the coating is an open challenge. Herein, we report on a radically new nanostructured coating, obtained by a one-step gas-phase deposition technique, and composed of bi-elemental Janus type Ag/Ti NPs. The NPs are characterized by a cluster-in-cluster mixing phase with metallic Ag nano-crystals embedded in amorphous TiO2 and present a promising antimicrobial activity including also multidrug resistant strains. We demonstrate the flexibility of the method to tune the embedded Ag nano-crystals dimension, the total relative composition of the coating, and the substrate type, opening the possibility of tailoring the dimension, composition, antimicrobial spectrum, and other physical/chemical properties of such multi-elemental systems. This work is expected to significantly spread the range of applications of NPs coatings, not only as an effective tool in the prevention of healthcare-associated infections but also in other technologically relevant fields like sensors or nano-/micro joining.
Persistent topological features of dynamical systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maletić, Slobodan, E-mail: slobodan@hitsz.edu.cn; Institute of Nuclear Sciences Vinča, University of Belgrade, Belgrade; Zhao, Yi, E-mail: zhao.yi@hitsz.edu.cn
Inspired by an early work of Muldoon et al., Physica D 65, 1–16 (1993), we present a general method for constructing simplicial complex from observed time series of dynamical systems based on the delay coordinate reconstruction procedure. The obtained simplicial complex preserves all pertinent topological features of the reconstructed phase space, and it may be analyzed from topological, combinatorial, and algebraic aspects. In focus of this study is the computation of homology of the invariant set of some well known dynamical systems that display chaotic behavior. Persistent homology of simplicial complex and its relationship with the embedding dimensions are examinedmore » by studying the lifetime of topological features and topological noise. The consistency of topological properties for different dynamic regimes and embedding dimensions is examined. The obtained results shed new light on the topological properties of the reconstructed phase space and open up new possibilities for application of advanced topological methods. The method presented here may be used as a generic method for constructing simplicial complex from a scalar time series that has a number of advantages compared to the mapping of the same time series to a complex network.« less
The embedding problem in topological dynamics and Takens’ theorem
NASA Astrophysics Data System (ADS)
Gutman, Yonatan; Qiao, Yixiao; Szabó, Gábor
2018-02-01
We prove that every {Z}k -action (X, {Z}k, T) of mean dimension less than D/2 admitting a factor (Y, {Z}k, S) of Rokhlin dimension not greater than L embeds in (([0, 1](L+1)D){\\hspace{0pt}}{Zk}× Y, σ× S) , where D\\in{N} , L\\in{N}\\cup\\{0\\} and σ is the shift on the Hilbert cube ([0, 1](L+1)D){\\hspace{0pt}}{Zk} ; in particular, when (Y, {Z}k, S) is an irrational {Z}k -rotation on the k-torus, (X, {Z}k, T) embeds in (([0, 1]2^kD+1){\\hspace{0pt}}{Z^k}, σ) , which is compared to a previous result in Gutman, Lindenstrauss and Tsukamoto (2016 Geom. Funct. Anal. 3 778-817). Moreover, we give a complete and detailed proof of Takens’ embedding theorem with a continuous observable for {Z} -actions and deduce the analogous result for {Z}k -actions. Lastly, we show that the Lindenstrauss-Tsukamoto conjecture for {Z} -actions holds generically, discuss an analogous conjecture for {Z}k -actions in Gutman, Qiao and Tsukamoto (2017 arXiv:1709.00125) and verify it for {Z}k -actions on finite dimensional spaces.
NASA Astrophysics Data System (ADS)
Barrios, Carlos Angulo; Canalejas-Tejero, Víctor
2017-01-01
The coupling efficiency at normal incidence of recently demonstrated aluminum grating couplers integrated in flexible Scotch tape waveguides has been analyzed theoretically and experimentally. Finite difference time domain (FDTD) and rigorously coupled wave analysis (RCWA) methods have been used to optimize the dimensions (duty cycle and metal thickness) of Scotch tape-embedded 1D Al gratings for maximum coupling at 635 nm wavelength. Good dimension and tape refractive index tolerances are predicted. FDTD simulations reveal the incident beam width and impinging position (alignment) values that avoid rediffraction and thus maximize the coupling efficiency. A 1D Al diffraction grating integrated into a Scotch tape optical waveguide has been fabricated and characterized. The fabrication process, based on pattern transfer, has been optimized to allow complete Al grating transfer onto the Scotch tape waveguide. A maximum coupling efficiency of 20% for TM-polarized normal incidence has been measured, which is in good agreement with the theoretical predictions. The measured coupling efficiency is further increased up to 28% for TM polarization under oblique incidence. Temperature dependence measurements have been also achieved and related to the simulations results and fabrication procedure.
NASA Astrophysics Data System (ADS)
Baik, Ki-Ho; Dean, Robert L.; Mueller, Mark; Lu, Maiying; Lem, Homer Y.; Osborne, Stephen; Abboud, Frank E.
2002-07-01
A chemically amplified resist (CAR) process has been recognized as an approach to meet the demanding critical dimension (CD) specifications of 100nm node technology and beyond. Recently, significant effort has been devoted to optimizing CAR materials, which offer the characteristics required for next generation photomask fabrication. In this paper, a process established with a positive-tone CAR from TOK and 50kV MEBES eXara system is discussed. This resist is developed for raster scan 50 kV e-beam systems. It has high contrast, good coating characteristics, good dry etch selectivity, and high environmental stability. The coating process is conducted in an environment with amine concentration less than 2 ppb. A nitrogen environment is provided during plate transfer steps. Resolution using a 60nm writing grid is 90nm line and space patterns. CD linearity is maintained down to 240nm for isolated lines or spaces by applying embedded proximity effect correction (emPEC). Optimizations of post-apply bake (PAB) and post-expose bake (PEB) time, temperature, and uniformity are completed to improve adhesion, coating uniformity, and resolution. A puddle develop process is optimized to improve line edge roughness, edge slope, and resolution. Dry etch process is optimized on a TetraT system to transfer the resist image into the chrome layer with minimum etch bias.
Ankle rehabilitation device with two degrees of freedom and compliant joint
NASA Astrophysics Data System (ADS)
Racu (Cazacu, C.-M.; Doroftei, I.
2015-11-01
We propose a rehabilitation device that we intend to be low cost and easy to manufacture. The system will ensure functionality but also have a small dimensions and low mass, considering the physiological dimensions of the foot and lower leg. To avoid injure of the ankle joint, this device is equipped with a compliant joint between the motor and mechanical transmission. The torque of this joint is intended to be adjustable, according to the degree of ankle joint damage. To choose the material and the dimensions of this compliant joint, in this paper we perform the first stress simulation. The minimum torque is calculated, while the maximum torque is given by the preliminary chosen actuator.
Epistemic uncertainty propagation in energy flows between structural vibrating systems
NASA Astrophysics Data System (ADS)
Xu, Menghui; Du, Xiaoping; Qiu, Zhiping; Wang, Chong
2016-03-01
A dimension-wise method for predicting fuzzy energy flows between structural vibrating systems coupled by joints with epistemic uncertainties is established. Based on its Legendre polynomial approximation at α=0, both the minimum and maximum point vectors of the energy flow of interest are calculated dimension by dimension within the space spanned by the interval parameters determined by fuzzy those at α=0 and the resulted interval bounds are used to assemble the concerned fuzzy energy flows. Besides the proposed method, vertex method as well as two current methods is also applied. Comparisons among results by different methods are accomplished by two numerical examples and the accuracy of all methods is simultaneously verified by Monte Carlo simulation.
Habibi, Ehsanollah; Asaadi, Zahra; Hosseini, Seyed Mohsen
2011-01-01
BACKGROUND: This study is aimed to examine the appropriacy of school furniture to Iranian pupils′ anthropometric features. METHODS: The participants in this cross-sectional study were 493 boys and 489 girls with the age-range of 7 to 12 years who were selected through a multistage random cluster sampling procedure. Age, weight, height, and anthropometric dimensions were determined. RESULTS: This study indicates that there is a significant difference between the minimum and maximum acceptable dimensions and those of the available furniture (p < 0.001). CONCLUSIONS: In designing suitable furniture for pupils the anthropometric differences of age and gender must be taken into account. PMID:21448391
On function classes related pertaining to strong approximation of double Fourier series
NASA Astrophysics Data System (ADS)
Baituyakova, Zhuldyz
2015-09-01
The investigation of embedding of function classes began a long time ago. After Alexits [1], Leindler [2], and Gogoladze[3] investigated estimates of strong approximation by Fourier series in 1965, G. Freud[4] raised the corresponding saturation problem in 1969. The list of the authors dealing with embedding problems partly is also very long. It suffices to mention some names: V. G. Krotov, W. Lenski, S. M. Mazhar, J. Nemeth, E. M. Nikisin, K. I. Oskolkov, G. Sunouchi, J. Szabados, R. Taberski and V. Totik. Study on this topic has since been carried on over a decade, but it seems that most of the results obtained are limited to the case of one dimension. In this paper, embedding results are considered which arise in the strong approximation by double Fourier series. We prove theorem on the interrelation between the classes Wr1,r2HS,M ω and H(λ, p, r1, r2, ω(δ1, δ2)), in the one-dimensional case proved by L. Leindler.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Song, Jiaming; Hudak, Bethany M.; Sims, Hunter
One-dimensional (1D) nanostructures are highly sought after, both for their novel electronic properties as well as for their improved functionality. However, due to their nanoscale dimensions, these properties are significantly affected by the environment in which they are embedded. Here in this paper, we report on the creation of 1D homo-endotaxial Si nanostructures, i.e. 1D Si nanostructures with a lattice structure that is uniquely different from the Si diamond lattice in which they are embedded. We use scanning tunneling microscopy and spectroscopy, scanning transmission electron microscopy, density functional theory, and conductive atomic force microscopy to elucidate their formation and properties.more » Depending on kinetic constraints during growth, they can be prepared as endotaxial 1D Si nanostructures completely embedded in crystalline Si, or underneath a stripe of amorphous Si containing a large concentration of Bi atoms. Lastly, these homo-endotaxial 1D Si nanostructures have the potential to be useful components in nanoelectronic devices based on the technologically mature Si platform.« less
New technique of skin embedded wire double-sided laser beam welding
NASA Astrophysics Data System (ADS)
Han, Bing; Tao, Wang; Chen, Yanbin
2017-06-01
In the aircraft industry, double-sided laser beam welding is an approved method for producing skin-stringer T-joints on aircraft fuselage panels. As for the welding of new generation aluminum-lithium alloys, however, this technique is limited because of high hot cracking susceptibility and strengthening elements' uneven distributions within weld. In the present study, a new technique of skin embedded wire double-sided laser beam welding (LBW) has been developed to fabricate T-joints consisting of 2.0 mm thick 2060-T8/2099-T83 aluminum-lithium alloys using eutectic alloy AA4047 filler wire. Necessary dimension parameters of the novel groove were reasonably designed for achieving crack-free welds. Comparisons were made between the new technique welded T-joint and conventional T-joint mainly on microstructure, hot crack, elements distribution features and mechanical properties within weld. Excellent crack-free microstructure, uniform distribution of silicon and superior tensile properties within weld were found in the new skin embedded wire double-sided LBW T-joints.
A novel attack method about double-random-phase-encoding-based image hiding method
NASA Astrophysics Data System (ADS)
Xu, Hongsheng; Xiao, Zhijun; Zhu, Xianchen
2018-03-01
By using optical image processing techniques, a novel text encryption and hiding method applied by double-random phase-encoding technique is proposed in the paper. The first step is that the secret message is transformed into a 2-dimension array. The higher bits of the elements in the array are used to fill with the bit stream of the secret text, while the lower bits are stored specific values. Then, the transformed array is encoded by double random phase encoding technique. Last, the encoded array is embedded on a public host image to obtain the image embedded with hidden text. The performance of the proposed technique is tested via analytical modeling and test data stream. Experimental results show that the secret text can be recovered either accurately or almost accurately, while maintaining the quality of the host image embedded with hidden data by properly selecting the method of transforming the secret text into an array and the superimposition coefficient.
Homo-endotaxial one-dimensional Si nanostructures
Song, Jiaming; Hudak, Bethany M.; Sims, Hunter; ...
2017-11-29
One-dimensional (1D) nanostructures are highly sought after, both for their novel electronic properties as well as for their improved functionality. However, due to their nanoscale dimensions, these properties are significantly affected by the environment in which they are embedded. Here in this paper, we report on the creation of 1D homo-endotaxial Si nanostructures, i.e. 1D Si nanostructures with a lattice structure that is uniquely different from the Si diamond lattice in which they are embedded. We use scanning tunneling microscopy and spectroscopy, scanning transmission electron microscopy, density functional theory, and conductive atomic force microscopy to elucidate their formation and properties.more » Depending on kinetic constraints during growth, they can be prepared as endotaxial 1D Si nanostructures completely embedded in crystalline Si, or underneath a stripe of amorphous Si containing a large concentration of Bi atoms. Lastly, these homo-endotaxial 1D Si nanostructures have the potential to be useful components in nanoelectronic devices based on the technologically mature Si platform.« less
NASA Astrophysics Data System (ADS)
Buyadzhi, V. V.; Glushkov, A. V.; Khetselius, O. Yu; Bunyakova, Yu Ya; Florko, T. A.; Agayar, E. V.; Solyanikova, E. P.
2017-10-01
The present paper concerns the results of computational studying dynamics of the atmospheric pollutants (dioxide of nitrogen, sulphur etc) concentrations in an atmosphere of the industrial cities (Odessa) by using the dynamical systems and chaos theory methods. A chaotic behaviour in the nitrogen dioxide and sulphurous anhydride concentration time series at several sites of the Odessa city is numerically investigated. As usually, to reconstruct the corresponding attractor, the time delay and embedding dimension are needed. The former is determined by the methods of autocorrelation function and average mutual information, and the latter is calculated by means of a correlation dimension method and algorithm of false nearest neighbours. Further, the Lyapunov’s exponents spectrum, Kaplan-Yorke dimension and Kolmogorov entropy are computed. It has been found an existence of a low-D chaos in the time series of the atmospheric pollutants concentrations.
McMahon, Christopher J; Toomey, Joshua P; Kane, Deb M
2017-01-01
We have analysed large data sets consisting of tens of thousands of time series from three Type B laser systems: a semiconductor laser in a photonic integrated chip, a semiconductor laser subject to optical feedback from a long free-space-external-cavity, and a solid-state laser subject to optical injection from a master laser. The lasers can deliver either constant, periodic, pulsed, or chaotic outputs when parameters such as the injection current and the level of external perturbation are varied. The systems represent examples of experimental nonlinear systems more generally and cover a broad range of complexity including systematically varying complexity in some regions. In this work we have introduced a new procedure for semi-automatically interrogating experimental laser system output power time series to calculate the correlation dimension (CD) using the commonly adopted Grassberger-Proccacia algorithm. The new CD procedure is called the 'minimum gradient detection algorithm'. A value of minimum gradient is returned for all time series in a data set. In some cases this can be identified as a CD, with uncertainty. Applying the new 'minimum gradient detection algorithm' CD procedure, we obtained robust measurements of the correlation dimension for many of the time series measured from each laser system. By mapping the results across an extended parameter space for operation of each laser system, we were able to confidently identify regions of low CD (CD < 3) and assign these robust values for the correlation dimension. However, in all three laser systems, we were not able to measure the correlation dimension at all parts of the parameter space. Nevertheless, by mapping the staged progress of the algorithm, we were able to broadly classify the dynamical output of the lasers at all parts of their respective parameter spaces. For two of the laser systems this included displaying regions of high-complexity chaos and dynamic noise. These high-complexity regions are differentiated from regions where the time series are dominated by technical noise. This is the first time such differentiation has been achieved using a CD analysis approach. More can be known of the CD for a system when it is interrogated in a mapping context, than from calculations using isolated time series. This has been shown for three laser systems and the approach is expected to be useful in other areas of nonlinear science where large data sets are available and need to be semi-automatically analysed to provide real dimensional information about the complex dynamics. The CD/minimum gradient algorithm measure provides additional information that complements other measures of complexity and relative complexity, such as the permutation entropy; and conventional physical measurements.
McMahon, Christopher J.; Toomey, Joshua P.
2017-01-01
Background We have analysed large data sets consisting of tens of thousands of time series from three Type B laser systems: a semiconductor laser in a photonic integrated chip, a semiconductor laser subject to optical feedback from a long free-space-external-cavity, and a solid-state laser subject to optical injection from a master laser. The lasers can deliver either constant, periodic, pulsed, or chaotic outputs when parameters such as the injection current and the level of external perturbation are varied. The systems represent examples of experimental nonlinear systems more generally and cover a broad range of complexity including systematically varying complexity in some regions. Methods In this work we have introduced a new procedure for semi-automatically interrogating experimental laser system output power time series to calculate the correlation dimension (CD) using the commonly adopted Grassberger-Proccacia algorithm. The new CD procedure is called the ‘minimum gradient detection algorithm’. A value of minimum gradient is returned for all time series in a data set. In some cases this can be identified as a CD, with uncertainty. Findings Applying the new ‘minimum gradient detection algorithm’ CD procedure, we obtained robust measurements of the correlation dimension for many of the time series measured from each laser system. By mapping the results across an extended parameter space for operation of each laser system, we were able to confidently identify regions of low CD (CD < 3) and assign these robust values for the correlation dimension. However, in all three laser systems, we were not able to measure the correlation dimension at all parts of the parameter space. Nevertheless, by mapping the staged progress of the algorithm, we were able to broadly classify the dynamical output of the lasers at all parts of their respective parameter spaces. For two of the laser systems this included displaying regions of high-complexity chaos and dynamic noise. These high-complexity regions are differentiated from regions where the time series are dominated by technical noise. This is the first time such differentiation has been achieved using a CD analysis approach. Conclusions More can be known of the CD for a system when it is interrogated in a mapping context, than from calculations using isolated time series. This has been shown for three laser systems and the approach is expected to be useful in other areas of nonlinear science where large data sets are available and need to be semi-automatically analysed to provide real dimensional information about the complex dynamics. The CD/minimum gradient algorithm measure provides additional information that complements other measures of complexity and relative complexity, such as the permutation entropy; and conventional physical measurements. PMID:28837602
Visualizing Chemical Interaction Dynamics of Confined DNA Molecules
NASA Astrophysics Data System (ADS)
Henkin, Gilead; Berard, Daniel; Stabile, Frank; Leslie, Sabrina
We present a novel nanofluidic approach to controllably introducing reagent molecules to interact with confined biopolymers and visualizing the reaction dynamics in real time. By dynamically deforming a flow cell using CLiC (Convex Lens-induced Confinement) microscopy, we are able to tune reaction chamber dimensions from micrometer to nanometer scales. We apply this gentle deformation to load and extend DNA polymers within embedded nanotopographies and visualize their interactions with other molecules in solution. Quantifying the change in configuration of polymers within embedded nanotopographies in response to binding/unbinding of reagent molecules provides new insights into their consequent change in physical properties. CLiC technology enables an ultra sensitive, massively parallel biochemical analysis platform which can acces a broader range of interaction parameters than existing devices.
Monitoring changing dynamics with correlation integrals: Case study of an epileptic seizure
NASA Astrophysics Data System (ADS)
Lerner, David E.
We describe a procedure (and the motivation behind it) which rapidly and accurately tracks the onset and progress of an epileptic seizure. Roughly speaking, one monitors changes in the relative dispersion of a re-embedded time series. The results are robust with respect to variation of adjustable parameters such as embedding dimension, lag time, and critical distances. Moreover, the general method is virtually unaffected when the data are significantly corrupted by external noise. When the information computed for the individual channels is displayed in an appropriate space-time plot, the progress and geometric location of the seizure are easily seen. An interpretation of these results in terms of a cloud of particles moving in an abstract phase space is examined.
Magneto-phonon polaritons in two-dimension antiferromagnetic/ion-crystalic photonic crystals
NASA Astrophysics Data System (ADS)
Ta, J. X.; Song, Y. L.; Wang, X. Z.
2012-01-01
Magneto-phonon polaritons in a two-dimension photonic crystal (PC) are discussed. This PC is constructed by embedding a periodical square lattice of ionic-crystal cylinders into an antiferromagnet. The two media are dispersive, with their individual resonant frequencies near each other. We first set up an effective-medium method to obtain the effective magnetic permeability and dielectric permittivity of the PC, followed by the dispersion relations of surface and bulk polaritons. There are a number of new surface polaritons, and two new distinctive bulk polariton bands in which the negative refraction and left-handedness can appear. The numerical calculations are based on the example, FeF2/TlBr PC.
16 CFR 301.27 - Label and method of affixing.
Code of Federal Regulations, 2010 CFR
2010-01-01
... all times during the marketing of a fur product the required label shall have a minimum dimension of one and three-fourths (13/4) inches by two and three-fourths (23/4) inches (4.5 cm × 7 cm). Such label...
The Mobility Decision. 1990 Wheelchair Guide.
ERIC Educational Resources Information Center
Henke, Cliff
1990-01-01
This article presents tips for parents shopping for wheelchairs for children with special mobility needs. Manual versus power chairs, dimensions, maneuverability, weight, transportability, durability, adaptability, maximum/minimum speeds, battery life (for power chairs), climbing angle, and other features are discussed. Factors to consider in…
NASA Technical Reports Server (NTRS)
Fincannon, O. J.; Glenn, D. L.
1972-01-01
Characteristics of steering assembly for vehicle designed to move large components of space flight vehicles are presented. Design makes it possible to move heavy and bulky items through narrow passageways with tight turns. Typical configuration is illustrated to show dimensions of turning radius and minimum distances involved.
30 CFR 7.43 - Application requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
... APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Battery Assemblies § 7.43 Application requirements. (a) An application for approval of a battery assembly shall contain sufficient information to... the following information: (1) Overall dimensions of the battery assembly, including the minimum...
30 CFR 7.43 - Application requirements.
Code of Federal Regulations, 2012 CFR
2012-07-01
... APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Battery Assemblies § 7.43 Application requirements. (a) An application for approval of a battery assembly shall contain sufficient information to... the following information: (1) Overall dimensions of the battery assembly, including the minimum...
Long, Zhen; Zhang, Yanhai; Gamache, Paul; Guo, Zhimou; Steiner, Frank; Du, Nana; Liu, Xiaoda; Jin, Yan; Liu, Xingguo; Liu, Lvye
2018-01-01
Current Chinese Pharmacopoeia (ChP) standards apply liquid extraction combined with one dimensional liquid chromatography (1DLC) method for determining alkaloids in herbal medicines. The complex pretreatments lead to a low analytical efficiency and possible component loss. In this study, a heart cutting reversed phase - strong cation exchange two dimensional liquid chromatography (RP - SCX 2DLC) approach was optimized for simultaneously quantifying tropane alkaloids (anisodine, scopolamine and hyoscyamine) in herbal medicines and herbal medicine tablets without further treatment of the filtered extract. The chromatographic conditions were systematically optimized in terms of column type, mobile phase composition and flow rate. To improve peak capacity and obtain symmetric peak shape of alkaloids, a polar group embedded C18 column combined with chaotropic salts was used in the first dimension. To remove the disturbance of non-alkaloids, achieve unique selectivity and acquire symmetric peak shape of alkaloids, an SCX column combined with phosphate buffer was used in the second dimension. Method validation was performed in terms of linearity, precision (0.54-0.82%), recovery (94.1-105.2%), limit of detection (LOD) and limit of quantification (LOQ) of the three analytes varied between 0.067-0.115mgL -1 and 0.195-0.268mgL -1 , respectively. The method demonstrated superiority over 1DLC method in respect of resolution (less alkaloid co-eluted), sample preparation (no pretreatment procedure) and transfer rate (minimum component loss). The optimized RP - SCX 2DLC approach was subsequently applied to quantify target alkaloids in five herbal medicines and herbal medicine tablets from three different manufactures. The results demonstrated that the developed heart cutting RP - SCX 2DLC approach represented a new, strategically significant methodology for the quality evaluation of tropane alkaloid in related herbal medicines that involve complex chemical matrix. Copyright © 2017. Published by Elsevier B.V.
ERIC Educational Resources Information Center
Dobson, Darrell
2005-01-01
This paper can be conceived as one story embedded in a second story, in which the "outer" narrative, involving the theoretical and methodological framework, is that of my search for a means of defining, articulating and implementing an aesthetic epistemology in both academic research and in teacher education/development (a search that is…
ERIC Educational Resources Information Center
Fisher, Wayne W.; Kodak, Tiffany; Moore, James W.
2007-01-01
Least-to-most prompting hierarchies (e.g., progressing from verbal to modeled to physical prompts until the target response occurs) may be ineffective when the prompts do not cue the individual to attend to the relevant stimulus dimensions. In such cases, emission of the target response persistently requires one or more of the higher level…
Roton Minimum as a Fingerprint of Magnon-Higgs Scattering in Ordered Quantum Antiferromagnets.
Powalski, M; Uhrig, G S; Schmidt, K P
2015-11-13
A quantitative description of magnons in long-range ordered quantum antiferromagnets is presented which is consistent from low to high energies. It is illustrated for the generic S=1/2 Heisenberg model on the square lattice. The approach is based on a continuous similarity transformation in momentum space using the scaling dimension as the truncation criterion. Evidence is found for significant magnon-magnon attraction inducing a Higgs resonance. The high-energy roton minimum in the magnon dispersion appears to be induced by strong magnon-Higgs scattering.
Shape optimization of the modular press body
NASA Astrophysics Data System (ADS)
Pabiszczak, Stanisław
2016-12-01
A paper contains an optimization algorithm of cross-sectional dimensions of a modular press body for the minimum mass criterion. Parameters of the wall thickness and the angle of their inclination relative to the base of section are assumed as the decision variables. The overall dimensions are treated as a constant. The optimal values of parameters were calculated using numerical method of the tool Solver in the program Microsoft Excel. The results of the optimization procedure helped reduce body weight by 27% while maintaining the required rigidity of the body.
1989-06-01
for stainless steel airlines of a nominal length of 7.5 cm, a temperature .hanne of +30C changes the length about ±--_1 electrical degree at 18 GHz...regions, each of which satisfies the source- free boundary conditions. The sum of these modes are then matched to the source discontinuity. The wave...dimension H, perpendicular to the array, represents a free dimension in linear array design limited only by the minimum field-of-view (FOV) orthogonal
Trellis coding with multidimensional QAM signal sets
NASA Technical Reports Server (NTRS)
Pietrobon, Steven S.; Costello, Daniel J.
1993-01-01
Trellis coding using multidimensional QAM signal sets is investigated. Finite-size 2D signal sets are presented that have minimum average energy, are 90-deg rotationally symmetric, and have from 16 to 1024 points. The best trellis codes using the finite 16-QAM signal set with two, four, six, and eight dimensions are found by computer search (the multidimensional signal set is constructed from the 2D signal set). The best moderate complexity trellis codes for infinite lattices with two, four, six, and eight dimensions are also found. The minimum free squared Euclidean distance and number of nearest neighbors for these codes were used as the selection criteria. Many of the multidimensional codes are fully rotationally invariant and give asymptotic coding gains up to 6.0 dB. From the infinite lattice codes, the best codes for transmitting J, J + 1/4, J + 1/3, J + 1/2, J + 2/3, and J + 3/4 bit/sym (J an integer) are presented.
Sign phase transition in the problem of interfering directed paths
NASA Astrophysics Data System (ADS)
Baldwin, C. L.; Laumann, C. R.; Spivak, B.
2018-01-01
We investigate the statistical properties of interfering directed paths in disordered media. At long distance, the average sign of the sum over paths may tend to zero (sign disordered) or remain finite (sign ordered) depending on dimensionality and the concentration of negative scattering sites x . We show that in two dimensions the sign-ordered phase is unstable even for arbitrarily small x by identifying rare destabilizing events. In three dimensions, we present strong evidence that there is a sign phase transition at a finite xc>0 . These results have consequences for several different physical systems. In two-dimensional insulators at low temperature, the variable-range-hopping magnetoresistance is always negative, while in three dimensions, it changes sign at the point of the sign phase transition. We also show that in the sign-disordered regime a small magnetic field may enhance superconductivity in a random system of D -wave superconducting grains embedded in a metallic matrix. Finally, the existence of the sign phase transition in three dimensions implies new features in the spin-glass phase diagram at high temperature.
Noormohammadpour, Pardis; Tavana, Bahareh; Mansournia, Mohammad Ali; Zeinalizadeh, Mehdi; Mirzashahi, Babak; Rostami, Mohsen; Kordi, Ramin
2018-05-01
Translation and cultural adaptation of the National Institutes of Health (NIH) Task Force's minimal dataset. The purpose of this study was to evaluate validity and reliability of the Farsi version of NIH Task Force's recommended multidimensional minimal dataset for research on chronic low back pain (CLBP). Considering the high treatment cost of CLBP and its increasing prevalence, NIH Pain Consortium developed research standards (including recommendations for definitions, a minimum dataset, and outcomes' report) for studies regarding CLBP. Application of these recommendations could standardize research and improve comparability of different studies in CLBP. This study has three phases: translation of dataset into Farsi and its cultural adaptation, assessment of pre-final version of dataset's comprehensibility via a pilot study, and investigation of the reliability and validity of final version of translated dataset. Subjects were 250 patients with CLBP. Test-retest reliability, content validity, and convergent validity (correlations among different dimensions of dataset and Farsi versions of Oswestry Disability Index, Roland Morris Disability Questionnaire, Fear-Avoidance Belief Questionnaire, and Beck Depression Inventory-II) were assessed. The Farsi version demonstrated good/excellent convergent validity (the correlation coefficient between impact dimension and ODI was r = 0.75 [P < 0.001], between impact dimension and Roland-Morris Disability Questionnaire was r = 0.80 [P < 0.001], and between psychological dimension and BDI was r = 0.62 [P < 0.001]). The test-retest reliability was also strong (intraclass correlation coefficient value ranged between 0.70 and 0.95) and the internal consistency was good/excellent (Chronbach's alpha coefficients' value for two main dimensions including impact dimension and psychological dimension were 0.91 and 0.82 [P < 0.001], respectively). In addition, its face validity and content validity were acceptable. The Farsi version of minimal dataset for research on CLBP is a reliable and valid instrument for data gathering in patients with CLBP. This minimum dataset can be a step toward standardization of research regarding CLBP. 3.
Fuss, Franz Konstantin
2013-01-01
Standard methods for computing the fractal dimensions of time series are usually tested with continuous nowhere differentiable functions, but not benchmarked with actual signals. Therefore they can produce opposite results in extreme signals. These methods also use different scaling methods, that is, different amplitude multipliers, which makes it difficult to compare fractal dimensions obtained from different methods. The purpose of this research was to develop an optimisation method that computes the fractal dimension of a normalised (dimensionless) and modified time series signal with a robust algorithm and a running average method, and that maximises the difference between two fractal dimensions, for example, a minimum and a maximum one. The signal is modified by transforming its amplitude by a multiplier, which has a non-linear effect on the signal's time derivative. The optimisation method identifies the optimal multiplier of the normalised amplitude for targeted decision making based on fractal dimensions. The optimisation method provides an additional filter effect and makes the fractal dimensions less noisy. The method is exemplified by, and explained with, different signals, such as human movement, EEG, and acoustic signals.
2013-01-01
Standard methods for computing the fractal dimensions of time series are usually tested with continuous nowhere differentiable functions, but not benchmarked with actual signals. Therefore they can produce opposite results in extreme signals. These methods also use different scaling methods, that is, different amplitude multipliers, which makes it difficult to compare fractal dimensions obtained from different methods. The purpose of this research was to develop an optimisation method that computes the fractal dimension of a normalised (dimensionless) and modified time series signal with a robust algorithm and a running average method, and that maximises the difference between two fractal dimensions, for example, a minimum and a maximum one. The signal is modified by transforming its amplitude by a multiplier, which has a non-linear effect on the signal's time derivative. The optimisation method identifies the optimal multiplier of the normalised amplitude for targeted decision making based on fractal dimensions. The optimisation method provides an additional filter effect and makes the fractal dimensions less noisy. The method is exemplified by, and explained with, different signals, such as human movement, EEG, and acoustic signals. PMID:24151522
Minimum Dimension of a Hilbert Space Needed to Generate a Quantum Correlation.
Sikora, Jamie; Varvitsiotis, Antonios; Wei, Zhaohui
2016-08-05
Consider a two-party correlation that can be generated by performing local measurements on a bipartite quantum system. A question of fundamental importance is to understand how many resources, which we quantify by the dimension of the underlying quantum system, are needed to reproduce this correlation. In this Letter, we identify an easy-to-compute lower bound on the smallest Hilbert space dimension needed to generate a given two-party quantum correlation. We show that our bound is tight on many well-known correlations and discuss how it can rule out correlations of having a finite-dimensional quantum representation. We show that our bound is multiplicative under product correlations and also that it can witness the nonconvexity of certain restricted-dimensional quantum correlations.
Mossotti, Victor G.; Eldeeb, A. Raouf; Oscarson, Robert
1998-01-01
MORPH-I is a set of C-language computer programs for the IBM PC and compatible minicomputers. The programs in MORPH-I are used for the fractal analysis of scanning electron microscope and electron microprobe images of pore profiles exposed in cross-section. The program isolates and traces the cross-sectional profiles of exposed pores and computes the Richardson fractal dimension for each pore. Other programs in the set provide for image calibration, display, and statistical analysis of the computed dimensions for highly complex porous materials. Requirements: IBM PC or compatible; minimum 640 K RAM; mathcoprocessor; SVGA graphics board providing mode 103 display.
The role of chief executive officers in a quality improvement initiative: a qualitative study
Parand, Anam; Dopson, Sue; Vincent, Charles
2013-01-01
Objectives To identify the critical dimensions of hospital Chief Executive Officers’ (CEOs) involvement in a quality and safety initiative and to offer practical guidance to assist CEOs to fulfil their leadership role in quality improvement (QI). Design Qualitative interview study. Setting 20 organisations participating in the main phase of the Safer Patients Initiative (SPI) programme across the UK. Participants 17 CEOs overseeing 19 organisations participating in the main phase of the SPI programme and 36 staff (20 workstream leads, 10 coordinators and 6 managers) involved in SPI across all 20 participating organisations. Main outcome measure Self-reported perceptions of CEOs on their contribution and involvement within the SPI programme, supplemented by staff peer-reports. Results The CEOs recognised the importance of their part in the SPI programme and gave detailed accounts of the perceived value that their involvement had brought at all stages of the process. In exploring the parts played by the CEOs, five dimensions were identified: (1) resource provision; (2) staff motivation and engagement; (3) commitment and support; (4) monitoring progress and (5) embedding programme elements. Staff reports confirmed these dimensions; however, the weighting of the dimensions differed. The findings stress the importance of particular actions of support and monitoring such as constant communication through leadership walk rounds and reviewing programme progress and its related clinical outcomes at Board meetings. Conclusions This study addressed the call for more research-informed practical guidance on the role of senior management in QI initiatives. The findings show that the CEOs provided key participation considered to significantly contribute towards the SPI programme. CEOs and staff identified a number of clear and consistent themes essential to organisation safety improvement. Queries raised include the tangible benefits of executive involvement in changing structures and embedding for sustainability and the practical steps to creating the ‘right’ environment for QI. PMID:23293245
Quantitative Analysis of Bone Microstructure Using Tomosynthesis
2013-10-01
resolution of separation, thickness, distances, in-plane and out-of-plane geometric distortion, and density linearity. 5 To assess the minimum spacing... geometric accuracy phantom was created using four 1 mm beads, placed in four corners at 35 mm apart (Figure 1f). An embedded human vertebra was also...included in the phantom as a realistic reference material (Figure 1g). Figure 1: Tray of phantoms to assess DTS resolution, geometric distortion
Quantitative Analysis of Bone Microstructure Using Tomosynthesis
2012-10-01
resolution of separation, thickness, distances, in-plane and out-of-plane geometric distortion, and density linearity. To assess the minimum spacing...volume, a geometric accuracy phantom was created using four 1 mm beads, placed in four corners at 35 mm apart (Figure 1f). An embedded human vertebra...was also included in the phantom as a realistic reference material (Figure 1g). Figure 1: Tray of phantoms to assess DTS resolution, geometric
Some trees with partition dimension three
NASA Astrophysics Data System (ADS)
Fredlina, Ketut Queena; Baskoro, Edy Tri
2016-02-01
The concept of partition dimension of a graph was introduced by Chartrand, E. Salehi and P. Zhang (1998) [2]. Let G(V, E) be a connected graph. For S ⊆ V (G) and v ∈ V (G), define the distance d(v, S) from v to S is min{d(v, x)|x ∈ S}. Let Π be an ordered partition of V (G) and Π = {S1, S2, ..., Sk }. The representation r(v|Π) of vertex v with respect to Π is (d(v, S1), d(v, S2), ..., d(v, Sk)). If the representations of all vertices are distinct, then the partition Π is called a resolving partition of G. The partition dimension of G is the minimum k such that G has a resolving partition with k partition classes. In this paper, we characterize some classes of trees with partition dimension three, namely olive trees, weeds, and centipedes.
A Simple ab initio Model for the Hydrated Electron that Matches Experiment
Kumar, Anil; Walker, Jonathan A.; Bartels, David M.; Sevilla, Michael D.
2015-01-01
Since its discovery over 50 years ago, the “structure” and properties of the hydrated electron has been a subject for wonderment and also fierce debate. In the present work we seriously explore a minimal model for the aqueous electron, consisting of a small water anion cluster embedded in a polarized continuum, using several levels of ab initio calculation and basis set. The minimum energy zero “Kelvin” structure found for any 4-water (or larger) anion cluster, at any post-Hartree-Fock theory level, is very similar to a recently reported embedded-DFT-in-classical-water-MD simulation (UMJ: Uhlig, Marsalek, and Jungwirth, Journal of Physical Chemistry Letters 2012, 3, 3071-5), with four OH bonds oriented toward the maximum charge density in a small central “void”. The minimum calculation with just four water molecules does a remarkably good job of reproducing the resonance Raman properties, the radius of gyration derived from the optical spectrum, the vertical detachment energy, and the hydration free energy. For the first time we also successfully calculate the EPR g-factor and (low temperature ice) hyperfine couplings. The simple tetrahedral anion cluster model conforms very well to experiment, suggesting it does in fact represent the dominant structural motif of the hydrated electron. PMID:26275103
NASA Astrophysics Data System (ADS)
Cheng, Shaobo; Zhang, Dong; Deng, Shiqing; Li, Xing; Li, Jun; Tan, Guotai; Zhu, Yimei; Zhu, Jing
2018-04-01
Topological defects and their interactions often arouse multiple types of emerging phenomena from edge states in Skyrmions to disclination pairs in liquid crystals. In hexagonal manganites, partial edge dislocations, a prototype topological defect, are ubiquitous and they significantly alter the topologically protected domains and their behaviors. Herein, combining electron microscopy experiment and graph theory analysis, we report a systematic study of the connections and configurations of domains in this dislocation embedded system. Rules for domain arrangement are established. The dividing line between domains, which can be attributed by the strain field of dislocations, is accurately described by a genus model from a higher dimension in the graph theory. Our results open a door for the understanding of domain patterns in topologically protected multiferroic systems.
Molecular Dynamics Simulation Studies of Fracture in Two Dimensions
1980-05-01
reversibility of trajectories. The microscopic elastic constants, dispersion relation and phonon spectrum of the system were determined by lattice dynamics. These... linear elasticity theory of a two-dimensional crack embedded in an infinite medium. System con- sists of 436 particles arranged in a tri- angular lattice ...satisfying these demands. In evaluating the mechanical energy of his model, Griffith used a result from linear elasticity theory, namely that for any body
A Graph-Embedding Approach to Hierarchical Visual Word Mergence.
Wang, Lei; Liu, Lingqiao; Zhou, Luping
2017-02-01
Appropriately merging visual words are an effective dimension reduction method for the bag-of-visual-words model in image classification. The approach of hierarchically merging visual words has been extensively employed, because it gives a fully determined merging hierarchy. Existing supervised hierarchical merging methods take different approaches and realize the merging process with various formulations. In this paper, we propose a unified hierarchical merging approach built upon the graph-embedding framework. Our approach is able to merge visual words for any scenario, where a preferred structure and an undesired structure are defined, and, therefore, can effectively attend to all kinds of requirements for the word-merging process. In terms of computational efficiency, we show that our algorithm can seamlessly integrate a fast search strategy developed in our previous work and, thus, well maintain the state-of-the-art merging speed. To the best of our survey, the proposed approach is the first one that addresses the hierarchical visual word mergence in such a flexible and unified manner. As demonstrated, it can maintain excellent image classification performance even after a significant dimension reduction, and outperform all the existing comparable visual word-merging methods. In a broad sense, our work provides an open platform for applying, evaluating, and developing new criteria for hierarchical word-merging tasks.
Chow, Sy-Miin; Bendezú, Jason J.; Cole, Pamela M.; Ram, Nilam
2016-01-01
Several approaches currently exist for estimating the derivatives of observed data for model exploration purposes, including functional data analysis (FDA), generalized local linear approximation (GLLA), and generalized orthogonal local derivative approximation (GOLD). These derivative estimation procedures can be used in a two-stage process to fit mixed effects ordinary differential equation (ODE) models. While the performance and utility of these routines for estimating linear ODEs have been established, they have not yet been evaluated in the context of nonlinear ODEs with mixed effects. We compared properties of the GLLA and GOLD to an FDA-based two-stage approach denoted herein as functional ordinary differential equation with mixed effects (FODEmixed) in a Monte Carlo study using a nonlinear coupled oscillators model with mixed effects. Simulation results showed that overall, the FODEmixed outperformed both the GLLA and GOLD across all the embedding dimensions considered, but a novel use of a fourth-order GLLA approach combined with very high embedding dimensions yielded estimation results that almost paralleled those from the FODEmixed. We discuss the strengths and limitations of each approach and demonstrate how output from each stage of FODEmixed may be used to inform empirical modeling of young children’s self-regulation. PMID:27391255
Chow, Sy-Miin; Bendezú, Jason J; Cole, Pamela M; Ram, Nilam
2016-01-01
Several approaches exist for estimating the derivatives of observed data for model exploration purposes, including functional data analysis (FDA; Ramsay & Silverman, 2005 ), generalized local linear approximation (GLLA; Boker, Deboeck, Edler, & Peel, 2010 ), and generalized orthogonal local derivative approximation (GOLD; Deboeck, 2010 ). These derivative estimation procedures can be used in a two-stage process to fit mixed effects ordinary differential equation (ODE) models. While the performance and utility of these routines for estimating linear ODEs have been established, they have not yet been evaluated in the context of nonlinear ODEs with mixed effects. We compared properties of the GLLA and GOLD to an FDA-based two-stage approach denoted herein as functional ordinary differential equation with mixed effects (FODEmixed) in a Monte Carlo (MC) study using a nonlinear coupled oscillators model with mixed effects. Simulation results showed that overall, the FODEmixed outperformed both the GLLA and GOLD across all the embedding dimensions considered, but a novel use of a fourth-order GLLA approach combined with very high embedding dimensions yielded estimation results that almost paralleled those from the FODEmixed. We discuss the strengths and limitations of each approach and demonstrate how output from each stage of FODEmixed may be used to inform empirical modeling of young children's self-regulation.
Terrill, Philip I; Wilson, Stephen J; Suresh, Sadasivam; Cooper, David M
2009-01-01
Breathing patterns are characteristically different between active and quiet sleep states in infants. It has been previously identified that breathing dynamics are governed by a non-linear controller which implies the need for a nonlinear analytical tool. Further, it has been shown that quantified nonlinear variables are different between adult sleep states. This study aims to determine whether a nonlinear analytical tool known as recurrence plot analysis can characterize breath intervals of active and quiet sleep states in infants. Overnight polysomnograms were obtained from 32 healthy infants. The 6 longest periods each of active and quiet sleep were identified and a software routine extracted inter-breath interval data for recurrence plot analysis. Determinism (DET), laminarity (LAM) and radius (RAD) values were calculated for an embedding dimension of 4, 6, 8 and 16, and fixed recurrence of 0.5, 1, 2, 3.5 and 5%. Recurrence plots exhibited characteristically different patterns for active and quiet sleep. Active sleep periods typically had higher values of RAD, DET and LAM than for quiet sleep, and this trend was invariant to a specific choice of embedding dimension or fixed recurrence. These differences may provide a basis for automated sleep state classification, and the quantitative investigation of pathological breathing patterns.
Fisher, Wayne W; Kodak, Tiffany; Moore, James W
2007-01-01
Least-to-most prompting hierarchies (e.g., progressing from verbal to modeled to physical prompts until the target response occurs) may be ineffective when the prompts do not cue the individual to attend to the relevant stimulus dimensions. In such cases, emission of the target response persistently requires one or more of the higher level prompts, a condition called prompt dependence (Clark & Green, 2004). Reinforcement of differential observing responses (DORs) has sometimes been used to ensure that participants attend to the relevant stimulus dimensions in matching-to-sample (MTS) tasks (e.g., Dube & McIlvane, 1999). For 2 participants with autism, we embedded an identity-matching task within a prompting hierarchy as a DOR to increase the likelihood that the participants attended to and discriminated the relevant features of the comparison stimuli in an MTS task. This procedure was compared with a traditional least-to-most prompting hierarchy and a no-reinforcement control condition in a multielement design. Results for both participants indicated that mastery-level acquisition of spoken-word-to-picture relations occurred only under the identity-matching condition. Findings are discussed relative to the use of DORs to facilitate acquisition of conditional discriminations in persons with autism or other conditions who do not attend to the comparison stimuli. PMID:17970262
Fisher, Wayne W; Kodak, Tiffany; Moore, James W
2007-01-01
Least-to-most prompting hierarchies (e.g., progressing from verbal to modeled to physical prompts until the target response occurs) may be ineffective when the prompts do not cue the individual to attend to the relevant stimulus dimensions. In such cases, emission of the target response persistently requires one or more of the higher level prompts, a condition called prompt dependence (Clark & Green, 2004). Reinforcement of differential observing responses (DORs) has sometimes been used to ensure that participants attend to the relevant stimulus dimensions in matching-to-sample (MTS) tasks (e.g., Dube & McIlvane, 1999). For 2 participants with autism, we embedded an identity-matching task within a prompting hierarchy as a DOR to increase the likelihood that the participants attended to and discriminated the relevant features of the comparison stimuli in an MTS task. This procedure was compared with a traditional least-to-most prompting hierarchy and a no-reinforcement control condition in a multielement design. Results for both participants indicated that mastery-level acquisition of spoken-word-to-picture relations occurred only under the identity-matching condition. Findings are discussed relative to the use of DORs to facilitate acquisition of conditional discriminations in persons with autism or other conditions who do not attend to the comparison stimuli.
A pseudospectra-based approach to non-normal stability of embedded boundary methods
NASA Astrophysics Data System (ADS)
Rapaka, Narsimha; Samtaney, Ravi
2017-11-01
We present non-normal linear stability of embedded boundary (EB) methods employing pseudospectra and resolvent norms. Stability of the discrete linear wave equation is characterized in terms of the normalized distance of the EB to the nearest ghost node (α) in one and two dimensions. An important objective is that the CFL condition based on the Cartesian grid spacing remains unaffected by the EB. We consider various discretization methods including both central and upwind-biased schemes. Stability is guaranteed when α <=αmax ranges between 0.5 and 0.77 depending on the discretization scheme. Also, the stability characteristics remain the same in both one and two dimensions. Sharper limits on the sufficient conditions for stability are obtained based on the pseudospectral radius (the Kreiss constant) than the restrictive limits based on the usual singular value decomposition analysis. We present a simple and robust reclassification scheme for the ghost cells (``hybrid ghost cells'') to ensure Lax stability of the discrete systems. This has been tested successfully for both low and high order discretization schemes with transient growth of at most O (1). Moreover, we present a stable, fourth order EB reconstruction scheme. Supported by the KAUST Office of Competitive Research Funds under Award No. URF/1/1394-01.
Quadrupolar, Triple [Delta]-Function Potential in One Dimension
ERIC Educational Resources Information Center
Patil, S. H.
2009-01-01
The energy and parity eigenstates for quadrupolar, triple [delta]-function potential are analysed. Using the analytical solutions in specific domains, simple expressions are obtained for even- and odd-parity bound-state energies. The Heisenberg uncertainty product is observed to have a minimum for a specific strength of the potential. The…
32 CFR 2001.53 - Open storage areas.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 32 National Defense 6 2012-07-01 2012-07-01 false Open storage areas. 2001.53 Section 2001.53....53 Open storage areas. This section describes the minimum construction standards for open storage... in its smallest dimension) that enter or pass through an open storage area shall be protected with...
32 CFR 2001.53 - Open storage areas.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 32 National Defense 6 2014-07-01 2014-07-01 false Open storage areas. 2001.53 Section 2001.53....53 Open storage areas. This section describes the minimum construction standards for open storage... in its smallest dimension) that enter or pass through an open storage area shall be protected with...
25 CFR 36.20 - Standard V-Minimum academic programs/school calendar.
Code of Federal Regulations, 2011 CFR
2011-04-01
..., physical education, music, etc.) which are directly related to or affect student instruction shall provide... dismissal of students by the school administration, the day may be counted as a school day provided that...-culture and multi-ethnic dimensions designed to enable students to function effectively in a pluralistic...
Zhang, Li; Qian, Liqiang; Ding, Chuntao; Zhou, Weida; Li, Fanzhang
2015-09-01
The family of discriminant neighborhood embedding (DNE) methods is typical graph-based methods for dimension reduction, and has been successfully applied to face recognition. This paper proposes a new variant of DNE, called similarity-balanced discriminant neighborhood embedding (SBDNE) and applies it to cancer classification using gene expression data. By introducing a novel similarity function, SBDNE deals with two data points in the same class and the different classes with different ways. The homogeneous and heterogeneous neighbors are selected according to the new similarity function instead of the Euclidean distance. SBDNE constructs two adjacent graphs, or between-class adjacent graph and within-class adjacent graph, using the new similarity function. According to these two adjacent graphs, we can generate the local between-class scatter and the local within-class scatter, respectively. Thus, SBDNE can maximize the between-class scatter and simultaneously minimize the within-class scatter to find the optimal projection matrix. Experimental results on six microarray datasets show that SBDNE is a promising method for cancer classification. Copyright © 2015 Elsevier Ltd. All rights reserved.
Huang, C.-Y.; Trask, R. S.; Bond, I. P.
2010-01-01
A study of the influence of embedded circular hollow vascules on structural performance of a fibre-reinforced polymer (FRP) composite laminate is presented. Incorporating such vascules will lead to multi-functional composites by bestowing functions such as self-healing and active thermal management. However, the presence of off-axis vascules leads to localized disruption to the fibre architecture, i.e. resin-rich pockets, which are regarded as internal defects and may cause stress concentrations within the structure. Engineering approaches for creating these simple vascule geometries in conventional FRP laminates are proposed and demonstrated. This study includes development of a manufacturing method for forming vascules, microscopic characterization of their effect on the laminate, finite element (FE) analysis of crack initiation and failure under load, and validation of the FE results via mechanical testing observed using high-speed photography. The failure behaviour predicted by FE modelling is in good agreement with experimental results. The reduction in compressive strength owing to the embedding of circular vascules ranges from 13 to 70 per cent, which correlates with vascule dimension. PMID:20150337
NASA Technical Reports Server (NTRS)
Troy, B. E., Jr.; Maier, E. J.
1975-01-01
The effects of the grid transparency and finite collector size on the values of thermal ion density and temperature determined by the standard RPA (retarding potential analyzer) analysis method are investigated. The current-voltage curves calculated for varying RPA parameters and a given ion mass, temperature, and density are analyzed by the standard RPA method. It is found that only small errors in temperature and density are introduced for an RPA with typical dimensions, and that even when the density error is substantial for nontypical dimensions, the temperature error remains minimum.
Cusp anomalous dimension and rotating open strings in AdS/CFT
NASA Astrophysics Data System (ADS)
Espíndola, R.; García, J. Antonio
2018-03-01
In the context of AdS/CFT we provide analytical support for the proposed duality between a Wilson loop with a cusp, the cusp anomalous dimension, and the meson model constructed from a rotating open string with high angular momentum. This duality was previously studied using numerical tools in [1]. Our result implies that the minimum of the profile function of the minimal area surface dual to the Wilson loop, is related to the inverse of the bulk penetration of the dual string that hangs from the quark-anti-quark pair (meson) in the gauge theory.
Wave energy focusing to subsurface poroelastic formations to promote oil mobilization
NASA Astrophysics Data System (ADS)
Karve, Pranav M.; Kallivokas, Loukas F.
2015-07-01
We discuss an inverse source formulation aimed at focusing wave energy produced by ground surface sources to target subsurface poroelastic formations. The intent of the focusing is to facilitate or enhance the mobility of oil entrapped within the target formation. The underlying forward wave propagation problem is cast in two spatial dimensions for a heterogeneous poroelastic target embedded within a heterogeneous elastic semi-infinite host. The semi-infiniteness of the elastic host is simulated by augmenting the (finite) computational domain with a buffer of perfectly matched layers. The inverse source algorithm is based on a systematic framework of partial-differential-equation-constrained optimization. It is demonstrated, via numerical experiments, that the algorithm is capable of converging to the spatial and temporal characteristics of surface loads that maximize energy delivery to the target formation. Consequently, the methodology is well-suited for designing field implementations that could meet a desired oil mobility threshold. Even though the methodology, and the results presented herein are in two dimensions, extensions to three dimensions are straightforward.
Characterization of chaotic dynamics in the human menstrual cycle
NASA Astrophysics Data System (ADS)
Derry, Gregory; Derry, Paula
2010-03-01
The human menstrual cycle exhibits much unexplained variability, which is typically dismissed as random variation. Given the many delayed nonlinear feedbacks in the reproductive endocrine system, however, the menstrual cycle might well be a nonlinear dynamical system in a chaotic trajectory, and that this instead accounts for the observed variability. Here, we test this hypothesis by performing a time series analysis on data for 7438 menstrual cycles from 38 women in the 20-40 year age range, using the database maintained by the Tremin Research Program on Women's Health. Using phase space reconstruction techniques with a maximum embedding dimension of 6, we find appropriate scaling behavior in the correlation sums for this data, indicating low dimensional deterministic dynamics. A correlation dimension of 2.6 is measured in this scaling regime, and this result is confirmed by recalculation using the Takens estimator. These results may be interpreted as offering an approximation to the fractal dimension of a strange attractor governing the chaotic dynamics of the menstrual cycle.
Secure Oblivious Hiding, Authentication, Tamper Proofing, and Verification Techniques
2002-08-01
compressing the bit- planes. The algorithm always starts with inspecting the 5th LSB plane. For color images , all three color-channels are compressed...use classical encryption engines, such as IDEA or DES . These algorithms have a fixed encryption block size, and, depending on the image dimensions, we...information can be stored either in a separate file, in the image header, or embedded in the image itself utilizing the modern concepts of steganography
Situation awareness - A critical but ill-defined phenomenon
NASA Technical Reports Server (NTRS)
Sarter, Nadine B.; Woods, David D.
1991-01-01
The significance of the temporal dimension of situation awareness is examined. Its study requires the staging of complex dynamic situations and the development of less intrusive in-flight probing techniques to assess the pilot's ability to adequately and rapidly retrieve and integrate flight-related information. The cognitive basis of the concept is analyzed, embedding it in the context of related psychological concepts. Methodological approaches to the investigation of situation awareness are discussed on this basis.
A New Method of Facial Expression Recognition Based on SPE Plus SVM
NASA Astrophysics Data System (ADS)
Ying, Zilu; Huang, Mingwei; Wang, Zhen; Wang, Zhewei
A novel method of facial expression recognition (FER) is presented, which uses stochastic proximity embedding (SPE) for data dimension reduction, and support vector machine (SVM) for expression classification. The proposed algorithm is applied to Japanese Female Facial Expression (JAFFE) database for FER, better performance is obtained compared with some traditional algorithms, such as PCA and LDA etc.. The result have further proved the effectiveness of the proposed algorithm.
Electromagnetic braking revisited with a magnetic point dipole model
NASA Astrophysics Data System (ADS)
Land, Sara; McGuire, Patrick; Bumb, Nikhil; Mann, Brian P.; Yellen, Benjamin B.
2016-04-01
A theoretical model is developed to predict the trajectory of magnetized spheres falling through a copper pipe. The derive magnetic point dipole model agrees well with the experimental trajectories for NdFeB spherical magnets of varying diameter, which are embedded inside 3D printed shells with fixed outer dimensions. This demonstration of electrodynamic phenomena and Lenz's law serves as a good laboratory exercise for physics, electromagnetics, and dynamics classes at the undergraduate level.
Military Dissent: What are the Ethical Implications of Tensions in U.S. Civil-Military Relations?
2013-06-14
they have social, political, economic, and moral components or dimensions that drive their design, formulation, and implementation. 2 According to...principles held by the Army profession and embedded in its culture (CAPE 2012). Army professional: A member of the Army profession who meets the Army’s...government. Ethics: A form of philosophy that deals with principles and concepts that guide right and wrong behavior (Mattox 2012). Ethos: The
Lutomski, J E; van Exel, N J A; Kempen, G I J M; Moll van Charante, E P; den Elzen, W P J; Jansen, A P D; Krabbe, P F M; Steunenberg, B; Steyerberg, E W; Olde Rikkert, M G M; Melis, R J F
2015-05-01
Validity is a contextual aspect of a scale which may differ across sample populations and study protocols. The objective of our study was to validate the Care-Related Quality of Life Instrument (CarerQol) across two different study design features, sampling framework (general population vs. different care settings) and survey mode (interview vs. written questionnaire). Data were extracted from The Older Persons and Informal Caregivers Minimum DataSet (TOPICS-MDS, www.topics-mds.eu ), a pooled public-access data set with information on >3,000 informal caregivers throughout the Netherlands. Meta-correlations and linear mixed models between the CarerQol's seven dimensions (CarerQol-7D) and caregiver's level of happiness (CarerQol-VAS) and self-rated burden (SRB) were performed. The CarerQol-7D dimensions were correlated to the CarerQol-VAS and SRB in the pooled data set and the subgroups. The strength of correlations between CarerQol-7D dimensions and SRB was weaker among caregivers who were interviewed versus those who completed a written questionnaire. The directionality of associations between the CarerQol-VAS, SRB and the CarerQol-7D dimensions in the multivariate model supported the construct validity of the CarerQol in the pooled population. Significant interaction terms were observed in several dimensions of the CarerQol-7D across sampling frame and survey mode, suggesting meaningful differences in reporting levels. Although good scientific practice emphasises the importance of re-evaluating instrument properties in individual research studies, our findings support the validity and applicability of the CarerQol instrument in a variety of settings. Due to minor differential reporting, pooling CarerQol data collected using mixed administration modes should be interpreted with caution; for TOPICS-MDS, meta-analytic techniques may be warranted.
Embedded scattering eigenstates using resonant metasurfaces
NASA Astrophysics Data System (ADS)
Krasnok, Alex; Alú, Andrea
2018-06-01
Optical embedded eigenstates (EEs) are localized modes of an open structure that are compatible to radiation, yet they have infinite lifetime and diverging quality factors. Their realization in nanostructures finite in all dimensions is inherently challenging, because they require materials with extreme electromagnetic properties. Here we explore the realization of these bound states in the continuum using ultrathin metasurfaces composed of arrays of nanoparticles. We first show that arrays of lossless nanoparticles can realize the condition for EEs, and then explore the use of Ag nanoparticles coated with gain media shells to compensate material loss and revive the EE despite realistic loss in plasmonic materials. We discuss the possible experimental realization of the proposed structures, and provide useful guidelines for practical implementation in nanophotonics systems with largely enhanced light–matter interactions. These metasurfaces may lead to highly efficient lasers, filters, frequency comb generation and sensors.
On the dual equivalence of the self-dual and topologically massive /p-form models
NASA Astrophysics Data System (ADS)
Menezes, R.; Nascimento, J. R. S.; Ribeiro, R. F.; Wotzasek, C.
2003-07-01
We study the duality symmetry in p-form models containing a generalized Bq∧Fp+1 term in spacetime manifolds of arbitrary dimensions. The equivalence between the Bq∧Fp+1 self-dual (SDB∧F) and the Bq∧Fp+1 topologically massive (TMB∧F) models is established using a gauge embedding procedure, including the minimal coupling to conserved charged matter current. The minimal coupling adopted for both tensor fields in the self-dual representation is transformed into a non-minimal magnetic like coupling in the topologically massive representation but with the currents swapped. It is known that to establish this equivalence a current-current interaction term is needed to render the matter sector unchanged. We show that both terms arise naturally from the embedding adopted. Comparison with Higgs/Julia-Toulouse duality is established.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cheng, Shaobo; Zhang, Dong; Deng, Shiqing
Topological defects and their interactions often arouse multiple types of emerging phenomena from edge states in Skyrmions to disclination pairs in liquid crystals. In hexagonal manganites, partial edge dislocations, a prototype topological defect, are ubiquitous and they significantly alter the topologically protected domains and their behaviors. In this work, combining electron microscopy experiment and graph theory analysis, we report a systematic study of the connections and configurations of domains in this dislocation embedded system. Rules for domain arrangement are established. The dividing line between domains, which can be attributed by the strain field of dislocations, is accurately described by amore » genus model from a higher dimension in the graph theory. In conclusion, our results open a door for the understanding of domain patterns in topologically protected multiferroic systems.« less
Cheng, Shaobo; Zhang, Dong; Deng, Shiqing; ...
2018-04-19
Topological defects and their interactions often arouse multiple types of emerging phenomena from edge states in Skyrmions to disclination pairs in liquid crystals. In hexagonal manganites, partial edge dislocations, a prototype topological defect, are ubiquitous and they significantly alter the topologically protected domains and their behaviors. In this work, combining electron microscopy experiment and graph theory analysis, we report a systematic study of the connections and configurations of domains in this dislocation embedded system. Rules for domain arrangement are established. The dividing line between domains, which can be attributed by the strain field of dislocations, is accurately described by amore » genus model from a higher dimension in the graph theory. In conclusion, our results open a door for the understanding of domain patterns in topologically protected multiferroic systems.« less
Code of Federal Regulations, 2012 CFR
2012-01-01
... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Bases. 1507.4 Section 1507.4 Commercial... § 1507.4 Bases. The base or bottom of fireworks devices that are operated in a standing upright position shall have the minimum horizontal dimensions or the diameter of the base equal to at least one-third of...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Bases. 1507.4 Section 1507.4 Commercial... § 1507.4 Bases. The base or bottom of fireworks devices that are operated in a standing upright position shall have the minimum horizontal dimensions or the diameter of the base equal to at least one-third of...
Ballistic Missile Propellant Evaluation Test Motor System (Super BATES)
1974-11-25
and laminated parts are debulked and 75 cured in a hydroclave at 950 psi (minimum) and 3000 F, and machined to final dimensions. All molded parts are...to pick dlf- ferent lengths of motors simply hy relocating and pinning the cross arms. flatbed truck with forklift will be i adequate for moving
Constraint elimination in dynamical systems
NASA Technical Reports Server (NTRS)
Singh, R. P.; Likins, P. W.
1989-01-01
Large space structures (LSSs) and other dynamical systems of current interest are often extremely complex assemblies of rigid and flexible bodies subjected to kinematical constraints. A formulation is presented for the governing equations of constrained multibody systems via the application of singular value decomposition (SVD). The resulting equations of motion are shown to be of minimum dimension.
49 CFR 172.315 - Limited quantities.
Code of Federal Regulations, 2011 CFR
2011-10-01
... accordance with the white square-on-point limited quantity marking as follows: (1) The limited quantity... forming the square-on-point must be at least 2 mm and the minimum dimension of each side must be 100 mm... top and bottom portions of the square-on-point and the border forming the square-on-point must be...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Bases. 1507.4 Section 1507.4 Commercial... § 1507.4 Bases. The base or bottom of fireworks devices that are operated in a standing upright position shall have the minimum horizontal dimensions or the diameter of the base equal to at least one-third of...
Effect of occlusal appliances and clenching on the internally deranged TMJ space.
Kuboki, T; Takenami, Y; Orsini, M G; Maekawa, K; Yamashita, A; Azuma, Y; Clark, G T
1999-01-01
Stabilization appliances and mandibular anterior repositioning appliances have been used to treat patients with internal derangement of the temporomandibular joint (TMJ) based on the assumption that these appliances work by decompressing the TMJ. The purpose of this study was to indirectly test this assumption. Bilateral TMJ tomograms of 7 subjects with unilateral anterior disc displacement without reduction (ADDwor) were taken during comfortable closure and during maximum clenching in maximum intercuspation; tomograms were also taken with the 2 types of occlusal appliances in use. Outlines of the condyle and the temporal fossa were automatically determined by an edge-detection protocol, and the minimum joint space dimension of the joints with and without ADDwor was automatically measured for each experimental condition as the outcome variable. Upon comfortable closure and maximum clenching, the minimum joint space dimensions of the ipsilateral and contralateral joints with the use of stabilization appliances and mandibular anterior repositioning appliances were not significantly different from those seen in maximum intercuspation. These findings do not indicate that these appliances induce an increase in joint space during closing and clenching in joints with ADDwor.
2008-01-15
grading scheme involves embedding particles only in the outer layers of a laminate , achieving maximal increases in bending stiffness with a minimum...by Eq. (19), with d=2. Longitudinal-transverse shear modulus The shear modulus for distortion of the laminate in axes with one direction aligned...The effective Poisson’s ratio νeLT is dictated by the other material constants of the laminate (Hill, 1964; Torquato, 2001): 12 νe LT = ν f + ν
Extreme learning machine based optimal embedding location finder for image steganography
Aljeroudi, Yazan
2017-01-01
In image steganography, determining the optimum location for embedding the secret message precisely with minimum distortion of the host medium remains a challenging issue. Yet, an effective approach for the selection of the best embedding location with least deformation is far from being achieved. To attain this goal, we propose a novel approach for image steganography with high-performance, where extreme learning machine (ELM) algorithm is modified to create a supervised mathematical model. This ELM is first trained on a part of an image or any host medium before being tested in the regression mode. This allowed us to choose the optimal location for embedding the message with best values of the predicted evaluation metrics. Contrast, homogeneity, and other texture features are used for training on a new metric. Furthermore, the developed ELM is exploited for counter over-fitting while training. The performance of the proposed steganography approach is evaluated by computing the correlation, structural similarity (SSIM) index, fusion matrices, and mean square error (MSE). The modified ELM is found to outperform the existing approaches in terms of imperceptibility. Excellent features of the experimental results demonstrate that the proposed steganographic approach is greatly proficient for preserving the visual information of an image. An improvement in the imperceptibility as much as 28% is achieved compared to the existing state of the art methods. PMID:28196080
Evaluating Small Sphere Limit of the Wang-Yau Quasi-Local Energy
NASA Astrophysics Data System (ADS)
Chen, Po-Ning; Wang, Mu-Tao; Yau, Shing-Tung
2018-01-01
In this article, we study the small sphere limit of the Wang-Yau quasi-local energy defined in Wang and Yau (Phys Rev Lett 102(2):021101, 2009, Commun Math Phys 288(3):919-942, 2009). Given a point p in a spacetime N, we consider a canonical family of surfaces approaching p along its future null cone and evaluate the limit of the Wang-Yau quasi-local energy. The evaluation relies on solving an "optimal embedding equation" whose solutions represent critical points of the quasi-local energy. For a spacetime with matter fields, the scenario is similar to that of the large sphere limit found in Chen et al. (Commun Math Phys 308(3):845-863, 2011). Namely, there is a natural solution which is a local minimum, and the limit of its quasi-local energy recovers the stress-energy tensor at p. For a vacuum spacetime, the quasi-local energy vanishes to higher order and the solution of the optimal embedding equation is more complicated. Nevertheless, we are able to show that there exists a solution that is a local minimum and that the limit of its quasi-local energy is related to the Bel-Robinson tensor. Together with earlier work (Chen et al. 2011), this completes the consistency verification of the Wang-Yau quasi-local energy with all classical limits.
NASA Astrophysics Data System (ADS)
Maleque, M. A.; Bello, K. A.; Adebisi, A. A.; Akma, N.
2017-03-01
Tungsten inert gas (TIG) torch is one of the most recently used heat source for surface modification of engineering parts, giving similar results to the more expensive high power laser technique. In this study, ceramic-based embedded composite coating has been produced by precoated silicon carbide (SiC) powders on the AISI 4340 low alloy steel substrate using TIG welding torch process. A design of experiment based on Taguchi approach has been adopted to optimize the TIG cladding process parameters. The L9 orthogonal array and the signal-to-noise was used to study the effect of TIG welding parameters such as arc current, travelling speed, welding voltage and argon flow rate on tribological response behaviour (wear rate, surface roughness and wear track width). The objective of the study was to identify optimal design parameter that significantly minimizes each of the surface quality characteristics. The analysis of the experimental results revealed that the argon flow rate was found to be the most influential factor contributing to the minimum wear and surface roughness of the modified coating surface. On the other hand, the key factor in reducing wear scar is the welding voltage. Finally, a convenient and economical Taguchi approach used in this study was efficient to find out optimal factor settings for obtaining minimum wear rate, wear scar and surface roughness responses in TIG-coated surfaces.
On the complexity and approximability of some Euclidean optimal summing problems
NASA Astrophysics Data System (ADS)
Eremeev, A. V.; Kel'manov, A. V.; Pyatkin, A. V.
2016-10-01
The complexity status of several well-known discrete optimization problems with the direction of optimization switching from maximum to minimum is analyzed. The task is to find a subset of a finite set of Euclidean points (vectors). In these problems, the objective functions depend either only on the norm of the sum of the elements from the subset or on this norm and the cardinality of the subset. It is proved that, if the dimension of the space is a part of the input, then all these problems are strongly NP-hard. Additionally, it is shown that, if the space dimension is fixed, then all the problems are NP-hard even for dimension 2 (on a plane) and there are no approximation algorithms with a guaranteed accuracy bound for them unless P = NP. It is shown that, if the coordinates of the input points are integer, then all the problems can be solved in pseudopolynomial time in the case of a fixed space dimension.
Denburg, Avram E; Knaul, Felicia M; Atun, Rifat; Frazier, Lindsay A; Barr, Ronald D
2014-03-01
Globally, the number of new cases of childhood cancer continues to rise, with a widening gulf in outcomes across countries, despite the availability of effective cure options for many pediatric cancers. Economic forces and health system realities are deeply embedded in the foundation of disparities in global childhood cancer outcomes. A truly global effort to close the childhood cancer divide therefore requires systemic solutions. Analysis of the economic and health system dimensions of childhood cancer outcomes is essential to progress in childhood cancer survival around the globe. The conceptual power of this approach is significant. It provides insight into how and where pediatric oncology entwines with broader political and economic conditions, and highlights the mutual benefit derived from systems-oriented solutions. © 2013 Wiley Periodicals, Inc.
Stabilizing embedology: Geometry-preserving delay-coordinate maps
NASA Astrophysics Data System (ADS)
Eftekhari, Armin; Yap, Han Lun; Wakin, Michael B.; Rozell, Christopher J.
2018-02-01
Delay-coordinate mapping is an effective and widely used technique for reconstructing and analyzing the dynamics of a nonlinear system based on time-series outputs. The efficacy of delay-coordinate mapping has long been supported by Takens' embedding theorem, which guarantees that delay-coordinate maps use the time-series output to provide a reconstruction of the hidden state space that is a one-to-one embedding of the system's attractor. While this topological guarantee ensures that distinct points in the reconstruction correspond to distinct points in the original state space, it does not characterize the quality of this embedding or illuminate how the specific parameters affect the reconstruction. In this paper, we extend Takens' result by establishing conditions under which delay-coordinate mapping is guaranteed to provide a stable embedding of a system's attractor. Beyond only preserving the attractor topology, a stable embedding preserves the attractor geometry by ensuring that distances between points in the state space are approximately preserved. In particular, we find that delay-coordinate mapping stably embeds an attractor of a dynamical system if the stable rank of the system is large enough to be proportional to the dimension of the attractor. The stable rank reflects the relation between the sampling interval and the number of delays in delay-coordinate mapping. Our theoretical findings give guidance to choosing system parameters, echoing the tradeoff between irrelevancy and redundancy that has been heuristically investigated in the literature. Our initial result is stated for attractors that are smooth submanifolds of Euclidean space, with extensions provided for the case of strange attractors.
Stabilizing embedology: Geometry-preserving delay-coordinate maps.
Eftekhari, Armin; Yap, Han Lun; Wakin, Michael B; Rozell, Christopher J
2018-02-01
Delay-coordinate mapping is an effective and widely used technique for reconstructing and analyzing the dynamics of a nonlinear system based on time-series outputs. The efficacy of delay-coordinate mapping has long been supported by Takens' embedding theorem, which guarantees that delay-coordinate maps use the time-series output to provide a reconstruction of the hidden state space that is a one-to-one embedding of the system's attractor. While this topological guarantee ensures that distinct points in the reconstruction correspond to distinct points in the original state space, it does not characterize the quality of this embedding or illuminate how the specific parameters affect the reconstruction. In this paper, we extend Takens' result by establishing conditions under which delay-coordinate mapping is guaranteed to provide a stable embedding of a system's attractor. Beyond only preserving the attractor topology, a stable embedding preserves the attractor geometry by ensuring that distances between points in the state space are approximately preserved. In particular, we find that delay-coordinate mapping stably embeds an attractor of a dynamical system if the stable rank of the system is large enough to be proportional to the dimension of the attractor. The stable rank reflects the relation between the sampling interval and the number of delays in delay-coordinate mapping. Our theoretical findings give guidance to choosing system parameters, echoing the tradeoff between irrelevancy and redundancy that has been heuristically investigated in the literature. Our initial result is stated for attractors that are smooth submanifolds of Euclidean space, with extensions provided for the case of strange attractors.
SIC-POVMS and MUBS: Geometrical Relationships in Prime Dimension
NASA Astrophysics Data System (ADS)
Appleby, D. M.
2009-03-01
The paper concerns Weyl-Heisenberg covariant SIC-POVMs (symmetric informationally complete positive operator valued measures) and full sets of MUBs (mutually unbiased bases) in prime dimension. When represented as vectors in generalized Bloch space a SIC-POVM forms a d2-1 dimensional regular simplex (d being the Hilbert space dimension). By contrast, the generalized Bloch vectors representing a full set of MUBs form d+1 mutually orthogonal d-1 dimensional regular simplices. In this paper we show that, in the Weyl-Heisenberg case, there are some simple geometrical relationships between the single SIC-POVM simplex and the d+1 MUB simplices. We go on to give geometrical interpretations of the minimum uncertainty states introduced by Wootters and Sussman, and by Appleby, Dang and Fuchs, and of the fiduciality condition given by Appleby, Dang and Fuchs.
Comparative analysis of nonlinear dimensionality reduction techniques for breast MRI segmentation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Akhbardeh, Alireza; Jacobs, Michael A.; Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
2012-04-15
Purpose: Visualization of anatomical structures using radiological imaging methods is an important tool in medicine to differentiate normal from pathological tissue and can generate large amounts of data for a radiologist to read. Integrating these large data sets is difficult and time-consuming. A new approach uses both supervised and unsupervised advanced machine learning techniques to visualize and segment radiological data. This study describes the application of a novel hybrid scheme, based on combining wavelet transform and nonlinear dimensionality reduction (NLDR) methods, to breast magnetic resonance imaging (MRI) data using three well-established NLDR techniques, namely, ISOMAP, local linear embedding (LLE), andmore » diffusion maps (DfM), to perform a comparative performance analysis. Methods: Twenty-five breast lesion subjects were scanned using a 3T scanner. MRI sequences used were T1-weighted, T2-weighted, diffusion-weighted imaging (DWI), and dynamic contrast-enhanced (DCE) imaging. The hybrid scheme consisted of two steps: preprocessing and postprocessing of the data. The preprocessing step was applied for B{sub 1} inhomogeneity correction, image registration, and wavelet-based image compression to match and denoise the data. In the postprocessing step, MRI parameters were considered data dimensions and the NLDR-based hybrid approach was applied to integrate the MRI parameters into a single image, termed the embedded image. This was achieved by mapping all pixel intensities from the higher dimension to a lower dimensional (embedded) space. For validation, the authors compared the hybrid NLDR with linear methods of principal component analysis (PCA) and multidimensional scaling (MDS) using synthetic data. For the clinical application, the authors used breast MRI data, comparison was performed using the postcontrast DCE MRI image and evaluating the congruence of the segmented lesions. Results: The NLDR-based hybrid approach was able to define and segment both synthetic and clinical data. In the synthetic data, the authors demonstrated the performance of the NLDR method compared with conventional linear DR methods. The NLDR approach enabled successful segmentation of the structures, whereas, in most cases, PCA and MDS failed. The NLDR approach was able to segment different breast tissue types with a high accuracy and the embedded image of the breast MRI data demonstrated fuzzy boundaries between the different types of breast tissue, i.e., fatty, glandular, and tissue with lesions (>86%). Conclusions: The proposed hybrid NLDR methods were able to segment clinical breast data with a high accuracy and construct an embedded image that visualized the contribution of different radiological parameters.« less
Computational Methods for Complex Flowfields
1989-07-05
This treatment is easily every ohrgi ie(i.9.Telclyfns el a extedd fo a-D knds pinerfces. Ths reuatemen rost e belong to either an unembedded or an...leading edge region is embedded in both directions. The downstream region between the two shear layers remains unembedded . Comparison of the grid and...A2 are unembedded coarse cells with vertical dimensions twice those of cells As, A4. It is clear that an evaluation for example, of the viscous
Interface with weakly singular points always scatter
NASA Astrophysics Data System (ADS)
Li, Long; Hu, Guanghui; Yang, Jiansheng
2018-07-01
Assume that a bounded scatterer is embedded into an infinite homogeneous isotropic background medium in two dimensions. The refractive index function is supposed to be piecewise constant. If the scattering interface contains a weakly singular point, we prove that the scattered field cannot vanish identically. This implies the absence of non-scattering energies for piecewise analytic interfaces with one singular point. Local uniqueness is obtained for shape identification problems in inverse medium scattering with a single far-field pattern.
Hencken, Kenneth R.; Sartor, George B.
2004-08-03
An electrokinetic pump in which the porous dielectric medium of conventional electrokinetic pumps is replaced by a patterned microstructure. The patterned microstructure is fabricated by lithographic patterning and etching of a substrate and is formed by features arranged so as to create an array of microchannels. The microchannels have dimensions on the order of the pore spacing in a conventional porous dielectric medium. Embedded unitary electrodes are vapor deposited on either end of the channel structure to provide the electric field necessary for electroosmotic flow.
NASA Astrophysics Data System (ADS)
Roy, Madhuparna
Composite textiles have found widespread use and advantages in various industries and applications. The constant demand for high quality products and services requires companies to minimize their manufacturing costs, and delivery time in order to compete in general and niche marketplaces. Advanced manufacturing methods aim to provide economical methods of mold production. Creation of molding and tooling options for advanced composites encompasses a large portion of the fabrication time, making it a costly process and restraining factor. This research discusses a preliminary investigation into the use of soluble polymer compounds and additive manufacturing to fabricate soluble molds. These molds suffer from dimensional errors due to several factors, which have also been characterized. The basic soluble mold of a composite is 3D printed to meet the desired dimensions and geometry of holistic structures or spliced components. The time taken to dissolve the mold depends on the rate of agitation of the solvent. This process is steered towards enabling the implantation of optoelectronic devices within the composite to provide sensing capability for structural health monitoring. The shape deviation of the 3D printed mold is also studied and compared to its original dimensions to optimize the dimensional quality to produce dimensionally accurate parts. Mechanical tests were performed on compact tension (CT) resin samples prepared from these 3D printed molds and revealed crack propagation towards an embedded intact optical fiber.
Mott transition between a spin-liquid insulator and a metal in three dimensions.
Podolsky, Daniel; Paramekanti, Arun; Kim, Yong Baek; Senthil, T
2009-05-08
We study a bandwidth controlled Mott metal-insulator transition (MIT) from a Fermi-liquid metal to a quantum spin-liquid insulator in three dimensions. Using a slave rotor approach including gauge fluctuations, we obtain a continuous MIT and discuss finite temperature crossovers in its vicinity. We show that the specific heat C approximately Tlnln(1/T) at the MIT and that the metallic state near the MIT should exhibit a "conductivity minimum" as a function of temperature. We suggest Na4Ir3O8 as a candidate to test our predictions and compute its electron spectral function at the MIT.
Initial Noise Assessment of an Embedded-wing-propulsion Concept Vehicle
NASA Technical Reports Server (NTRS)
Stone, James R.; Krejsa, Eugene A.
2008-01-01
Vehicle acoustic requirements are considered for a Cruise-Efficient Short Take-Off and Landing (CESTOL) vehicle concept using an Embedded-Wing-Propulsion (EWP) system based on a review of the literature. Successful development of such vehicles would enable more efficient use of existing airports in accommodating the anticipated growth in air traffic while at the same time reducing the noise impact on the community around the airport. A noise prediction capability for CESTOL-EWP aircraft is developed, based largely on NASA's FOOTPR code and other published methods, with new relations for high aspect ratio slot nozzles and wing shielding. The predictive model is applied to a preliminary concept developed by Boeing for NASA GRC. Significant noise reduction for such an aircraft relative to the current state-of-the-art is predicted, and technology issues are identified which should be addressed to assure that the potential of this design concept is fully achieved with minimum technical risk.
Sparsity prediction and application to a new steganographic technique
NASA Astrophysics Data System (ADS)
Phillips, David; Noonan, Joseph
2004-10-01
Steganography is a technique of embedding information in innocuous data such that only the innocent data is visible. The wavelet transform lends itself to image steganography because it generates a large number of coefficients representing the information in the image. Altering a small set of these coefficients allows embedding of information (payload) into an image (cover) without noticeably altering the original image. We propose a novel, dual-wavelet steganographic technique, using transforms selected such that the transform of the cover image has low sparsity, while the payload transform has high sparsity. Maximizing the sparsity of the payload transform reduces the amount of information embedded in the cover, and minimizing the sparsity of the cover increases the locations that can be altered without significantly altering the image. Making this system effective on any given image pair requires a metric to indicate the best (maximum sparsity) and worst (minimum sparsity) wavelet transforms to use. This paper develops the first stage of this metric, which can predict, averaged across many wavelet families, which of two images will have a higher sparsity. A prototype implementation of the dual-wavelet system as a proof of concept is also developed.
Computational techniques to enable visualizing shapes of objects of extra spatial dimensions
NASA Astrophysics Data System (ADS)
Black, Don Vaughn, II
Envisioning extra dimensions beyond the three of common experience is a daunting challenge for three dimensional observers. Intuition relies on experience gained in a three dimensional environment. Gaining experience with virtual four dimensional objects and virtual three manifolds in four-space on a personal computer may provide the basis for an intuitive grasp of four dimensions. In order to enable such a capability for ourselves, it is first necessary to devise and implement a computationally tractable method to visualize, explore, and manipulate objects of dimension beyond three on the personal computer. A technology is described in this dissertation to convert a representation of higher dimensional models into a format that may be displayed in realtime on graphics cards available on many off-the-shelf personal computers. As a result, an opportunity has been created to experience the shape of four dimensional objects on the desktop computer. The ultimate goal has been to provide the user a tangible and memorable experience with mathematical models of four dimensional objects such that the user can see the model from any user selected vantage point. By use of a 4D GUI, an arbitrary convex hull or 3D silhouette of the 4D model can be rotated, panned, scrolled, and zoomed until a suitable dimensionally reduced view or Aspect is obtained. The 4D GUI then allows the user to manipulate a 3-flat hyperplane cutting tool to slice the model at an arbitrary orientation and position to extract or "pluck" an embedded 3D slice or "aspect" from the embedding four-space. This plucked 3D aspect can be viewed from all angles via a conventional 3D viewer using three multiple POV viewports, and optionally exported to a third party CAD viewer for further manipulation. Plucking and Manipulating the Aspect provides a tangible experience for the end-user in the same manner as any 3D Computer Aided Design viewing and manipulation tool does for the engineer or a 3D video game provides for the nascent student.
NASA Astrophysics Data System (ADS)
Giacomel, L.; Manfrin, C.; Marchiori, G.
2008-07-01
From the first application on the VLT Telescopes till today, the linear motor identifies the best solution in terms of quality/cost for any technological application in the astronomical field. Its application also in the radio-astronomy sector with the ALMA project represents a whole of forefront technology, high reliability and minimum maintenance. The adoption of embedded electronics on each motor sector makes it a system at present modular, redundant with resetting of EMC troubles.
Rózyło-Kalinowska, Ingrid
2007-05-01
The distinction between radicular cysts and apical granulomas is a matter of considerable importance in making a treatment decision. Because there are no clearly defined radiographic criteria, the distinction is made on the grounds of size. However, it has been suggested that cysts can be distinguished from granulomas on the basis of their radiometric density. The results of previous studies have proved conflicting. To determine possibilities of application of digital radiography density measurements in differentiation of periapical granulomas and radicular cysts of inflammatory origin. The material consisted of 355 digital periapical radiograms obtained using Digora, RVG and Dixi 2 digital radiography systems in patients aged 20 to 84, divided into two groups: 259 granulomas and 102 radicular cysts. By means of Digora 2.0 software there were measured maximum and minimum densities along a line, then there was calculated the difference between maximum and minimum density. The largest dimensions of the lesions were measured - perpendicular and parallel to the root canal axis. It was proved that to some extent it was possible to differentiate cystic granulomas and radicular cysts on the basis of the difference between maximum and minimum density in linear measurement - when the difference exceeded 85.6 the lesion was a cyst and when it was below 45.9 a granuloma was diagnosed. Combination of two criteria - the calculated difference between densities and the largest dimension of a lesion, increased diagnostic possibilities of radiological differentiation of granulomas and radicular cysts.
Interception in three dimensions - An energy formulation
NASA Technical Reports Server (NTRS)
Rajan, N.; Ardema, M. D.
1983-01-01
The problem of minimum-time interception of a target flying in three dimensional space is analyzed with the interceptor aircraft modeled through energy-state approximation. A coordinate transformation that uncouples the interceptor's extremals from the target motion in an open-loop sense is introduced, and the necessary conditions for optimality and the optimal controls are derived. Example extremals are shown.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Bases. § 1507.4 Section § 1507.4... FIREWORKS DEVICES § 1507.4 Bases. The base or bottom of fireworks devices that are operated in a standing upright position shall have the minimum horizontal dimensions or the diameter of the base equal to at...
49 CFR 172.315 - Limited quantities.
Code of Federal Regulations, 2012 CFR
2012-10-01
... and bottom portions of the square-on-point and the border forming the square-on-point must be black and the center white or of a suitable contrasting background as follows: ER30DE11.004 (2) The square... the square-on-point must be at least 2 mm and the minimum dimension of each side must be 100 mm unless...
49 CFR 172.315 - Limited quantities.
Code of Federal Regulations, 2013 CFR
2013-10-01
... and bottom portions of the square-on-point and the border forming the square-on-point must be black and the center white or of a suitable contrasting background as follows: ER30DE11.004 (2) The square... the square-on-point must be at least 2 mm and the minimum dimension of each side must be 100 mm unless...
49 CFR 172.315 - Limited quantities.
Code of Federal Regulations, 2014 CFR
2014-10-01
... and bottom portions of the square-on-point and the border forming the square-on-point must be black and the center white or of a suitable contrasting background as follows: ER30DE11.004 (2) The square... the square-on-point must be at least 2 mm and the minimum dimension of each side must be 100 mm unless...
16 CFR 304.5 - Marking requirements for imitation political items.
Code of Federal Regulations, 2011 CFR
2011-01-01
...-serif numerals. Each numeral shall have a vertical dimension of not less than two millimeters (2.0 mm) and a minimum depth of three-tenths of one millimeter (0.3 mm) or one-half (1/2) the thickness of the... the calendar year shall be six millimeters (6.0 mm). (4) An imitation political button, poster...
Improving coarse woody debris measurements: a taper-based technique
Christopher W. Woodall; James A. Westfall
2007-01-01
Coarse woody debris (CWD) are dead and down trees of a certain minimum size that are an important forest ecosystem component (e.g., wildlife habitat, carbon stocks, and fuels). Accurately measuring the dimensions of CWD is important for ensuring the quality of CWD estimates and hence for accurately assessing forest ecosystem attributes. To improve the quality of CWD...
NASA Technical Reports Server (NTRS)
Camarda, Charles J.; Riley, Michael F.
1987-01-01
Nonlinear mathematical programming methods are used to design a radiantly cooled and heat-pipe-cooled panel for a Mach 6.7 transport. The cooled portion of the panel is a hybrid heat-pipe/actively cooled design which uses heat pipes to transport the absorbed heat to the ends of the panel where it is removed by active cooling. The panels are optimized for minimum mass and to satisfy a set of heat-pipe, structural, geometric, and minimum-gage constraints. Two panel concepts are investigated: cylindrical heat pipes embedded in a honeycomb core and an integrated design which uses a web-core heat-pipe sandwich concept. The latter was lighter and resulted in a design which was less than 10 percent heavier than an all actively cooled concept. The heat-pipe concept, however, is redundant and can sustain a single-point failure, whereas the actively cooled concept cannot. An additional study was performed to determine the optimum number of coolant manifolds per panel for a minimum-mass design.
Detection of LSB+/-1 steganography based on co-occurrence matrix and bit plane clipping
NASA Astrophysics Data System (ADS)
Abolghasemi, Mojtaba; Aghaeinia, Hassan; Faez, Karim; Mehrabi, Mohammad Ali
2010-01-01
Spatial LSB+/-1 steganography changes smooth characteristics between adjoining pixels of the raw image. We present a novel steganalysis method for LSB+/-1 steganography based on feature vectors derived from the co-occurrence matrix in the spatial domain. We investigate how LSB+/-1 steganography affects the bit planes of an image and show that it changes more least significant bit (LSB) planes of it. The co-occurrence matrix is derived from an image in which some of its most significant bit planes are clipped. By this preprocessing, in addition to reducing the dimensions of the feature vector, the effects of embedding were also preserved. We compute the co-occurrence matrix in different directions and with different dependency and use the elements of the resulting co-occurrence matrix as features. This method is sensitive to the data embedding process. We use a Fisher linear discrimination (FLD) classifier and test our algorithm on different databases and embedding rates. We compare our scheme with the current LSB+/-1 steganalysis methods. It is shown that the proposed scheme outperforms the state-of-the-art methods in detecting the LSB+/-1 steganographic method for grayscale images.
Monitoring of freeze-thaw cycles in concrete using embedded sensors and ultrasonic imaging.
Ranz, Javier; Aparicio, Sofía; Romero, Héctor; Casati, María Jesús; Molero, Miguel; González, Margarita
2014-01-29
This paper deals with the study of damage produced during freeze-thaw (F-T) cycles using two non-destructive measurement approaches-the first approach devoted to continuous monitoring using embedded sensors during the cycles, and the second one, performing ultrasonic imaging before and after the cycles. Both methodologies have been tested in two different types of concrete specimens, with and without air-entraining agents. Using the first measurement approach, the size and distribution of pores were estimated using a thermoporometrical model and continuous measurements of temperature and ultrasonic velocity along cycles. These estimates have been compared with the results obtained using mercury porosimetry testing. In the second approach, the damage due to F-T cycles has been evaluated by automated ultrasonic transmission and pulse-echo inspections made before and after the cycles. With these inspections the variations in the dimensions, velocity and attenuation caused by the accelerated F-T cycles were determined.
NASA Astrophysics Data System (ADS)
Chevrié, Mathieu; Farges, Christophe; Sabatier, Jocelyn; Guillemard, Franck; Pradere, Laetitia
2017-04-01
In automotive application field, reducing electric conductors dimensions is significant to decrease the embedded mass and the manufacturing costs. It is thus essential to develop tools to optimize the wire diameter according to thermal constraints and protection algorithms to maintain a high level of safety. In order to develop such tools and algorithms, accurate electro-thermal models of electric wires are required. However, thermal equation solutions lead to implicit fractional transfer functions involving an exponential that cannot be embedded in a car calculator. This paper thus proposes an integer order transfer function approximation methodology based on a spatial discretization for this class of fractional transfer functions. Moreover, the H2-norm is used to minimize approximation error. Accuracy of the proposed approach is confirmed with measured data on a 1.5 mm2 wire implemented in a dedicated test bench.
Dimensionless embedding for nonlinear time series analysis
NASA Astrophysics Data System (ADS)
Hirata, Yoshito; Aihara, Kazuyuki
2017-09-01
Recently, infinite-dimensional delay coordinates (InDDeCs) have been proposed for predicting high-dimensional dynamics instead of conventional delay coordinates. Although InDDeCs can realize faster computation and more accurate short-term prediction, it is still not well-known whether InDDeCs can be used in other applications of nonlinear time series analysis in which reconstruction is needed for the underlying dynamics from a scalar time series generated from a dynamical system. Here, we give theoretical support for justifying the use of InDDeCs and provide numerical examples to show that InDDeCs can be used for various applications for obtaining the recurrence plots, correlation dimensions, and maximal Lyapunov exponents, as well as testing directional couplings and extracting slow-driving forces. We demonstrate performance of the InDDeCs using the weather data. Thus, InDDeCs can eventually realize "dimensionless embedding" while we enjoy faster and more reliable computations.
Embedded sparse representation of fMRI data via group-wise dictionary optimization
NASA Astrophysics Data System (ADS)
Zhu, Dajiang; Lin, Binbin; Faskowitz, Joshua; Ye, Jieping; Thompson, Paul M.
2016-03-01
Sparse learning enables dimension reduction and efficient modeling of high dimensional signals and images, but it may need to be tailored to best suit specific applications and datasets. Here we used sparse learning to efficiently represent functional magnetic resonance imaging (fMRI) data from the human brain. We propose a novel embedded sparse representation (ESR), to identify the most consistent dictionary atoms across different brain datasets via an iterative group-wise dictionary optimization procedure. In this framework, we introduced additional criteria to make the learned dictionary atoms more consistent across different subjects. We successfully identified four common dictionary atoms that follow the external task stimuli with very high accuracy. After projecting the corresponding coefficient vectors back into the 3-D brain volume space, the spatial patterns are also consistent with traditional fMRI analysis results. Our framework reveals common features of brain activation in a population, as a new, efficient fMRI analysis method.
Efficient solutions to the Euler equations for supersonic flow with embedded subsonic regions
NASA Technical Reports Server (NTRS)
Walters, Robert W.; Dwoyer, Douglas L.
1987-01-01
A line Gauss-Seidel (LGS) relaxation algorithm in conjunction with a one-parameter family of upwind discretizations of the Euler equations in two dimensions is described. Convergence of the basic algorithm to the steady state is quadratic for fully supersonic flows and is linear for other flows. This is in contrast to the block alternating direction implicit methods (either central or upwind differenced) and the upwind biased relaxation schemes, all of which converge linearly, independent of the flow regime. Moreover, the algorithm presented herein is easily coupled with methods to detect regions of subsonic flow embedded in supersonic flow. This allows marching by lines in the supersonic regions, converging each line quadratically, and iterating in the subsonic regions, and yields a very efficient iteration strategy. Numerical results are presented for two-dimensional supersonic and transonic flows containing oblique and normal shock waves which confirm the efficiency of the iteration strategy.
Perceptualization of geometry using intelligent haptic and visual sensing
NASA Astrophysics Data System (ADS)
Weng, Jianguang; Zhang, Hui
2013-01-01
We present a set of paradigms for investigating geometric structures using haptic and visual sensing. Our principal test cases include smoothly embedded geometry shapes such as knotted curves embedded in 3D and knotted surfaces in 4D, that contain massive intersections when projected to one lower dimension. One can exploit a touch-responsive 3D interactive probe to haptically override this conflicting evidence in the rendered images, by forcing continuity in the haptic representation to emphasize the true topology. In our work, we exploited a predictive haptic guidance, a "computer-simulated hand" with supplementary force suggestion, to support intelligent exploration of geometry shapes that will smooth and maximize the probability of recognition. The cognitive load can be reduced further when enabling an attention-driven visual sensing during the haptic exploration. Our methods combine to reveal the full richness of the haptic exploration of geometric structures, and to overcome the limitations of traditional 4D visualization.
Monitoring of Freeze-Thaw Cycles in Concrete Using Embedded Sensors and Ultrasonic Imaging
Ranz, Javier; Aparicio, Sofía; Romero, Héctor; Casati, María Jesús; Molero, Miguel; González, Margarita
2014-01-01
This paper deals with the study of damage produced during freeze-thaw (F-T) cycles using two non-destructive measurement approaches—the first approach devoted to continuous monitoring using embedded sensors during the cycles, and the second one, performing ultrasonic imaging before and after the cycles. Both methodologies have been tested in two different types of concrete specimens, with and without air-entraining agents. Using the first measurement approach, the size and distribution of pores were estimated using a thermoporometrical model and continuous measurements of temperature and ultrasonic velocity along cycles. These estimates have been compared with the results obtained using mercury porosimetry testing. In the second approach, the damage due to F-T cycles has been evaluated by automated ultrasonic transmission and pulse-echo inspections made before and after the cycles. With these inspections the variations in the dimensions, velocity and attenuation caused by the accelerated F-T cycles were determined. PMID:24481231
Sun, Jianhai; Cui, Dafu; Chen, Xing; Zhang, Lulu; Cai, Haoyuan; Li, Hui
2013-05-24
In this paper, a micro gas chromatography (μGC) column with embedded micro-posts was developed for increasing overall surface area of the columns which is able to support more of the stationary phase and reducing the effective width of the column, leading to higher separation efficiency. The proposed columns have a higher sample capacity as the overall surface area is about 3 times larger than that of open columns with the same dimensions. In order to achieve an even flow velocity in the channels, the location of the micro-posts in the linear channels and the configuration of curved channels were optimized by numerical simulation. The results have indicated that the proposed column separated 5 environmental carcinogens in less than 50s, achieved a separation efficiency of about 9500plates/m and eluted highly symmetrical Gaussian peaks. Copyright © 2013 Elsevier B.V. All rights reserved.
Fracture Surface Morphology and Impact Strength of Cellulose/PLA Composites.
Gao, Honghong; Qiang, Tao
2017-06-07
Polylactide (PLA)-based composite materials reinforced with ball-milled celluloses were manufactured by extrusion blending followed by injection molding. Their surface morphology from impact fracture were imaged with scanning electron microscopy (SEM) and investigated by calculating their fractal dimensions. Then, linear regression was used to explore the relationship between fractal dimension and impact strength of the resultant cellulose/PLA composite materials. The results show that filling the ball-milled celluloses into PLA can improve the impact toughness of PLA by a minimum of 38%. It was demonstrated that the fracture pattern of the cellulose/PLA composite materials is different from that of pristine PLA. For the resultant composite materials, the fractal dimension of the impact fractured surfaces increased with increasing filling content and decreasing particle size of the ball-milled cellulose particles. There were highly positive correlations between fractal dimension of the fractured surfaces and impact strength of the cellulose/PLA composites. However, the linearity between fractal dimension and impact strength were different for the different methods, due to their different R-squared values. The approach presented in this work will help to understand the structure-property relationships of composite materials from a new perspective.
Fracture Surface Morphology and Impact Strength of Cellulose/PLA Composites
Gao, Honghong; Qiang, Tao
2017-01-01
Polylactide (PLA)-based composite materials reinforced with ball-milled celluloses were manufactured by extrusion blending followed by injection molding. Their surface morphology from impact fracture were imaged with scanning electron microscopy (SEM) and investigated by calculating their fractal dimensions. Then, linear regression was used to explore the relationship between fractal dimension and impact strength of the resultant cellulose/PLA composite materials. The results show that filling the ball-milled celluloses into PLA can improve the impact toughness of PLA by a minimum of 38%. It was demonstrated that the fracture pattern of the cellulose/PLA composite materials is different from that of pristine PLA. For the resultant composite materials, the fractal dimension of the impact fractured surfaces increased with increasing filling content and decreasing particle size of the ball-milled cellulose particles. There were highly positive correlations between fractal dimension of the fractured surfaces and impact strength of the cellulose/PLA composites. However, the linearity between fractal dimension and impact strength were different for the different methods, due to their different R-squared values. The approach presented in this work will help to understand the structure–property relationships of composite materials from a new perspective. PMID:28772983
Fast secant methods for the iterative solution of large nonsymmetric linear systems
NASA Technical Reports Server (NTRS)
Deuflhard, Peter; Freund, Roland; Walter, Artur
1990-01-01
A family of secant methods based on general rank-1 updates was revisited in view of the construction of iterative solvers for large non-Hermitian linear systems. As it turns out, both Broyden's good and bad update techniques play a special role, but should be associated with two different line search principles. For Broyden's bad update technique, a minimum residual principle is natural, thus making it theoretically comparable with a series of well known algorithms like GMRES. Broyden's good update technique, however, is shown to be naturally linked with a minimum next correction principle, which asymptotically mimics a minimum error principle. The two minimization principles differ significantly for sufficiently large system dimension. Numerical experiments on discretized partial differential equations of convection diffusion type in 2-D with integral layers give a first impression of the possible power of the derived good Broyden variant.
Origin of gauge invariance in string theory
NASA Technical Reports Server (NTRS)
Horowitz, G. T.; Strominger, A.
1986-01-01
A first quantization of the space-time embedding Chi exp mu and the world-sheet metric rho of the open bosonic string. The world-sheet metric rho decouples from S-matrix elements in 26 dimensions. This formulation of the theory naturally includes 26-dimensional gauge transformations. The gauge invariance of S-matrix elements is a direct consequence of the decoupling of rho. Second quantization leads to a string field Phi(Chi exp mu, rho) with a gauge-covariant equation of motion.
Ray-optical theory of broadband partially coherent emission
NASA Astrophysics Data System (ADS)
Epstein, Ariel; Tessler, Nir; Einziger, Pinchas D.
2013-04-01
We present a rigorous formulation of the effects of spectral broadening on emission of partially coherent source ensembles embedded in multilayered formations with arbitrarily shaped interfaces, provided geometrical optics is valid. The resulting ray-optical theory, applicable to a variety of optical systems from terahertz lenses to photovoltaic cells, quantifies the fundamental interplay between bandwidth and layer dimensions, and sheds light on common practices in optical analysis of statistical fields, e.g., disregarding multiple reflections or neglecting interference cross terms.
AdS-phobia, the WGC, the Standard Model and Supersymmetry
NASA Astrophysics Data System (ADS)
Gonzalo, Eduardo; Herráez, Alvaro; Ibáñez, Luis E.
2018-06-01
It has been recently argued that an embedding of the SM into a consistent theory of quantum gravity may imply important constraints on the mass of the lightest neutrino and the cosmological constant Λ4. The constraints come from imposing the absence of any non-SUSY AdS stable vacua obtained from any consistent compactification of the SM to 3 or 2 dimensions. This condition comes as a corollary of a recent extension of the Weak Gravity Conjecture (WGC) by Ooguri and Vafa. In this paper we study T 2 /Z N compactifications of the SM to two dimensions in which SM Wilson lines are projected out, leading to a considerable simplification. We analyze in detail a T 2 /Z 4 compactification of the SM in which both complex structure and Wilson line scalars are fixed and the potential is only a function of the area of the torus a 2. We find that the SM is not robust against the appearance of AdS vacua in 2D and hence would be by itself inconsistent with quantum gravity. On the contrary, if the SM is embedded at some scale M SS into a SUSY version like the MSSM, the AdS vacua present in the non-SUSY case disappear or become unstable. This means that WGC arguments favor a SUSY version of the SM, independently of the usual hierarchy problem arguments. In a T 2 /Z 4 compactification in which the orbifold action is embedded into the B - L symmetry the bounds on neutrino masses and the cosmological constant are recovered. This suggests that the MSSM should be extended with a U(1) B- L gauge group. In other families of vacua the spectrum of SUSY particles is further constrained in order to avoid the appearance of new AdS vacua or instabilities. We discuss a possible understanding of the little hierarchy problem in this context.
Lai, Zheng Bo; Yan, Cheng
2017-01-01
Many biological composite materials such as bone have demonstrated unique mechanical performance, i.e., a combination of superior stiffness and toughness. It has become increasingly clear that the constituents at the nano- and micro-length scales play a critical role in determining the mechanical performance of these biological composites. In this study, the underlying mechanisms governing the mechanical behaviour of the staggered array of mineralised collagen fibrils (MCF) embedded in extra-fibrillar protein matrix were numerically investigated. The evolution of damage zone in protein was estimated using cohesive zone models (CZM). The results indicate that the mechanisms and mechanical behaviour of MCF array are largely dependent on the MCF dimensions and the intrinsic failure energy in extra-fibrillar protein matrix. Copyright © 2016 Elsevier Ltd. All rights reserved.
Lagrange multiplier and Wess-Zumino variable as extra dimensions in the torus universe
NASA Astrophysics Data System (ADS)
Nejad, Salman Abarghouei; Dehghani, Mehdi; Monemzadeh, Majid
2018-01-01
We study the effect of the simplest geometry which is imposed via the topology of the universe by gauging non-relativistic particle model on torus and 3-torus with the help of symplectic formalism of constrained systems. Also, we obtain generators of gauge transformations for gauged models. Extracting corresponding Poisson structure of existed constraints, we show the effect of the shape of the universe on canonical structure of phase-spaces of models and suggest some phenomenology to prove the topology of the universe and probable non-commutative structure of the space. In addition, we show that the number of extra dimensions in the phase-spaces of gauged embedded models are exactly two. Moreover, in classical form, we talk over modification of Newton's second law in order to study the origin of the terms appeared in the gauged theory.
Hawking temperature of constant curvature black holes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cai Ronggen; Myung, Yun Soo; Institute of Basic Science and School of Computer Aided Science, Inje University, Gimhae 621-749
2011-05-15
The constant curvature (CC) black holes are higher dimensional generalizations of Banados-Teitelboim-Zanelli black holes. It is known that these black holes have the unusual topology of M{sub D-1}xS{sup 1}, where D is the spacetime dimension and M{sub D-1} stands for a conformal Minkowski spacetime in D-1 dimensions. The unusual topology and time-dependence for the exterior of these black holes cause some difficulties to derive their thermodynamic quantities. In this work, by using a globally embedding approach, we obtain the Hawking temperature of the CC black holes. We find that the Hawking temperature takes the same form when using both themore » static and global coordinates. Also, it is identical to the Gibbons-Hawking temperature of the boundary de Sitter spaces of these CC black holes.« less
Bent dark soliton dynamics in two spatial dimensions beyond the mean field approximation
NASA Astrophysics Data System (ADS)
Mistakidis, Simeon; Katsimiga, Garyfallia; Koutentakis, Georgios; Kevrekidis, Panagiotis; Schmelcher, Peter; Theory Group of Fundamental Processes in Quantum Physics Team
2017-04-01
The dynamics of a bented dark soliton embedded in two spatial dimensions beyond the mean-field approximation is explored. We examine the case of a single bented dark soliton comparing the mean-field approximation to a correlated approach that involves multiple orbitals. Fragmentation is generally present and significantly affects the dynamics, especially in the case of stronger interparticle interactions and in that of lower atom numbers. It is shown that the presence of fragmentation allows for the appearance of solitonic and vortex structures in the higher-orbital dynamics. In particular, a variety of excitations including dark solitons in multiple orbitals and vortex-antidark complexes is observed to arise spontaneously within the beyond mean-field dynamics. Deutsche Forschungsgemeinschaft (DFG) in the framework of the SFB 925 ``Light induced dynamics and control of correlated quantum systems''.
NASA Astrophysics Data System (ADS)
Huang, Wen-Nan; Chen, Po-Shen; Chen, Mu-Ping; Teng, Ching-Cheng
2006-09-01
A novel design of the magnetic locator, for obtaining the high-precision measurement information of variety of the buried metal pipes, is presented in this paper. The concept of dynamically sensing mechanism, including the vibrating and moving devices, proposed herein is a simple and effective way to improve the precision of three-dimension location sensing for the underground utilities. Based on the primary magnetism of Lenz's law and Faraday's law, the functions of the amplifying effect for the sensing magnetic signals, as well as the distinguishing effect by the simple filtering algorithms embedded in processing programs, are achieved while the relatively strong noise exists. The verification results of these integration designs demonstrate the effectiveness both by precise locating for the buried utility, and accurate measurement for the depth.
Efimov effect in D spatial dimensions in A A B systems
NASA Astrophysics Data System (ADS)
Rosa, D. S.; Frederico, T.; Krein, G.; Yamashita, M. T.
2018-05-01
The existence of the Efimov effect is drastically affected by the dimensionality of the space in which the system is embedded. The effective spatial dimension containing an atomic cloud can be continuously modified by compressing it in one or two directions. In the present Rapid Communication we determine the dimensionality D for which the Efimov effect can exist for different values of the mass ratio A =mB/mA for a general A A B system formed by two identical bosons A and a third particle B in the two-body unitary limit. In addition, we provide a prediction for the Efimov discrete scaling factor exp(π /s ) as a function of a wide range of values of A and D , which can be tested in experiments that can be realized with currently available technology.
Mean first passage time of active Brownian particle in one dimension
NASA Astrophysics Data System (ADS)
Scacchi, A.; Sharma, A.
2018-02-01
We investigate the mean first passage time of an active Brownian particle in one dimension using numerical simulations. The activity in one dimension is modelled as a two state model; the particle moves with a constant propulsion strength but its orientation switches from one state to other as in a random telegraphic process. We study the influence of a finite resetting rate r on the mean first passage time to a fixed target of a single free active Brownian particle and map this result using an effective diffusion process. As in the case of a passive Brownian particle, we can find an optimal resetting rate r* for an active Brownian particle for which the target is found with the minimum average time. In the case of the presence of an external potential, we find good agreement between the theory and numerical simulations using an effective potential approach.
Collaborating for care: initial experience of embedded case managers across five medical homes.
Treadwell, Janet; Giardino, Angelo
2014-01-01
The purpose of this intervention was to answer the following question: Does an embedded nurse case manager from a health plan performing embedded care coordination and supporting a quality improvement project impact medical home service use, role satisfaction, and per member per month expense? The setting for this study was primary care medical home practices with a minimum of 1,000 lives, contracted with a health plan delivering Medicaid and Children's Health Insurance coverage. Five medical home practice sites were selected for the intervention. The study began with case manager training and project permission in 5 medical homes, followed by implementation of care coordination with health plan clients. The nurse case manager performed care coordination functions for clients and initiated a Lean Six Sigma quality improvement project at the medical home site. The analysis strategy was to compare each medical home with itself before and after the intervention, as well as to obtain satisfaction information from medical home staff and care coordinators. Reductions in expense, as demonstrated by decreased per member per month claim cost, admissions per thousand, and reduced variation in days per thousand, were documented. Quality projects attained significant improvements in 4 out of 5 sites, and practice staff as well as case managers described satisfaction with the embedded nurse case manager role. These findings support medical homes as being an effective delivery model of the Affordable Care Act. Case managers who practice in primary care sites can make a significant difference in patient outcomes and practice efficiencies. Embedded case managers have the ability to impact the population being served through modeling and supporting interprofessional relationships and case management expertise. Use of motivational interviewing, assessment skills, advocacy, and joint care planning engage patients in their own care, whereas quality initiatives bring efficiencies and effectiveness to overall operations. There is need for research to be conducted across a larger number of practice sites and diverse populations to substantiate the effect of embedded case management in medical home.
InGaAs/InP quantum wires grown on silicon with adjustable emission wavelength at telecom bands
NASA Astrophysics Data System (ADS)
Han, Yu; Li, Qiang; Ng, Kar Wei; Zhu, Si; Lau, Kei May
2018-06-01
We report the growth of vertically stacked InGaAs/InP quantum wires on (001) Si substrates with adjustable room-temperature emission at telecom bands. Based on a self-limiting growth mode in selective area metal–organic chemical vapor deposition, crescent-shaped InGaAs quantum wires with variable dimensions are embedded within InP nano-ridges. With extensive transmission electron microscopy studies, the growth transition and morphology change from quantum wires to ridge quantum wells (QWs) have been revealed. As a result, we are able to decouple the quantum wires from ridge QWs and manipulate their dimensions by scaling the growth time. With minimized lateral dimension and their unique positioning, the InGaAs/InP quantum wires are more immune to dislocations and more efficient in radiative processes, as evidenced by their excellent optical quality at telecom-bands. These promising results thus highlight the potential of combining low-dimensional quantum wire structures with the aspect ratio trapping process for integrating III–V nano-light emitters on mainstream (001) Si substrates.
NASA Astrophysics Data System (ADS)
Karedla, Narain; Chizhik, Anna M.; Stein, Simon C.; Ruhlandt, Daja; Gregor, Ingo; Chizhik, Alexey I.; Enderlein, Jörg
2018-05-01
Our paper presents the first theoretical and experimental study using single-molecule Metal-Induced Energy Transfer (smMIET) for localizing single fluorescent molecules in three dimensions. Metal-Induced Energy Transfer describes the resonant energy transfer from the excited state of a fluorescent emitter to surface plasmons in a metal nanostructure. This energy transfer is strongly distance-dependent and can be used to localize an emitter along one dimension. We have used Metal-Induced Energy Transfer in the past for localizing fluorescent emitters with nanometer accuracy along the optical axis of a microscope. The combination of smMIET with single-molecule localization based super-resolution microscopy that provides nanometer lateral localization accuracy offers the prospect of achieving isotropic nanometer localization accuracy in all three spatial dimensions. We give a thorough theoretical explanation and analysis of smMIET, describe its experimental requirements, also in its combination with lateral single-molecule localization techniques, and present first proof-of-principle experiments using dye molecules immobilized on top of a silica spacer, and of dye molecules embedded in thin polymer films.
On the Coupling Time of the Heat-Bath Process for the Fortuin-Kasteleyn Random-Cluster Model
NASA Astrophysics Data System (ADS)
Collevecchio, Andrea; Elçi, Eren Metin; Garoni, Timothy M.; Weigel, Martin
2018-01-01
We consider the coupling from the past implementation of the random-cluster heat-bath process, and study its random running time, or coupling time. We focus on hypercubic lattices embedded on tori, in dimensions one to three, with cluster fugacity at least one. We make a number of conjectures regarding the asymptotic behaviour of the coupling time, motivated by rigorous results in one dimension and Monte Carlo simulations in dimensions two and three. Amongst our findings, we observe that, for generic parameter values, the distribution of the appropriately standardized coupling time converges to a Gumbel distribution, and that the standard deviation of the coupling time is asymptotic to an explicit universal constant multiple of the relaxation time. Perhaps surprisingly, we observe these results to hold both off criticality, where the coupling time closely mimics the coupon collector's problem, and also at the critical point, provided the cluster fugacity is below the value at which the transition becomes discontinuous. Finally, we consider analogous questions for the single-spin Ising heat-bath process.
InGaAs/InP quantum wires grown on silicon with adjustable emission wavelength at telecom bands.
Han, Yu; Li, Qiang; Ng, Kar Wei; Zhu, Si; Lau, Kei May
2018-06-01
We report the growth of vertically stacked InGaAs/InP quantum wires on (001) Si substrates with adjustable room-temperature emission at telecom bands. Based on a self-limiting growth mode in selective area metal-organic chemical vapor deposition, crescent-shaped InGaAs quantum wires with variable dimensions are embedded within InP nano-ridges. With extensive transmission electron microscopy studies, the growth transition and morphology change from quantum wires to ridge quantum wells (QWs) have been revealed. As a result, we are able to decouple the quantum wires from ridge QWs and manipulate their dimensions by scaling the growth time. With minimized lateral dimension and their unique positioning, the InGaAs/InP quantum wires are more immune to dislocations and more efficient in radiative processes, as evidenced by their excellent optical quality at telecom-bands. These promising results thus highlight the potential of combining low-dimensional quantum wire structures with the aspect ratio trapping process for integrating III-V nano-light emitters on mainstream (001) Si substrates.
Existence and construction of Galilean invariant z ≠2 theories
NASA Astrophysics Data System (ADS)
Grinstein, Benjamín; Pal, Sridip
2018-06-01
We prove a no-go theorem for the construction of a Galilean boost invariant and z ≠2 anisotropic scale invariant field theory with a finite dimensional basis of fields. Two point correlators in such theories, we show, grow unboundedly with spatial separation. Correlators of theories with an infinite dimensional basis of fields, for example, labeled by a continuous parameter, do not necessarily exhibit this bad behavior. Hence, such theories behave effectively as if in one extra dimension. Embedding the symmetry algebra into the conformal algebra of one higher dimension also reveals the existence of an internal continuous parameter. Consideration of isometries shows that the nonrelativistic holographic picture assumes a canonical form, where the bulk gravitational theory lives in a space-time with one extra dimension. This can be contrasted with the original proposal by Balasubramanian and McGreevy, and by Son, where the metric of a (d +2 )-dimensional space-time is proposed to be dual of a d -dimensional field theory. We provide explicit examples of theories living at fixed point with anisotropic scaling exponent z =2/ℓ ℓ+1 , ℓ∈Z .
REVIEWS OF TOPICAL PROBLEMS: Cosmological branes and macroscopic extra dimensions
NASA Astrophysics Data System (ADS)
Barvinsky, Andrei O.
2005-06-01
The idea of adding extra dimensions to the physical world — thus making the observable universe a timelike surface (or brane) embedded in a higher-dimensional space-time — is briefly reviewed, which is believed to hold serious promise for solving fundamental problems concerning the hierarchy of physical interactions and the cosmological constant. Brane localization of massless gravitons is discussed as a mechanism leading to the effective four-dimensional Einstein gravity theory on the brane in the low-energy limit. It is shown that this mechanism is a corollary of the AdS/CFT correspondence principle well-known from string theory. Inflation and other cosmological evolution scenarios induced by the local and nonlocal structures of the effective action of the gravitational brane are considered, as are the effects that enable the developing gravitational-wave astronomy to be used in the search for extra dimensions. Finally, a new approach to the cosmological constant and cosmological acceleration problems is discussed, which involves variable local and nonlocal gravitational 'constants' arising in the infrared modifications of the Einstein theory that incorporate brane-induced gravity models and models of massive gravitons.
Selective weighting of action-related feature dimensions in visual working memory.
Heuer, Anna; Schubö, Anna
2017-08-01
Planning an action primes feature dimensions that are relevant for that particular action, increasing the impact of these dimensions on perceptual processing. Here, we investigated whether action planning also affects the short-term maintenance of visual information. In a combined memory and movement task, participants were to memorize items defined by size or color while preparing either a grasping or a pointing movement. Whereas size is a relevant feature dimension for grasping, color can be used to localize the goal object and guide a pointing movement. The results showed that memory for items defined by size was better during the preparation of a grasping movement than during the preparation of a pointing movement. Conversely, memory for color tended to be better when a pointing movement rather than a grasping movement was being planned. This pattern was not only observed when the memory task was embedded within the preparation period of the movement, but also when the movement to be performed was only indicated during the retention interval of the memory task. These findings reveal that a weighting of information in visual working memory according to action relevance can even be implemented at the representational level during maintenance, demonstrating that our actions continue to influence visual processing beyond the perceptual stage.
Post, R.F.; Taylor, C.E.
1963-05-21
A cryogenic magnet coil is described for generating magnetic fields of the order of 100,000 gauss with a minimum expenditure of energy lost in resistive heating of the coil inductors and energy lost irreversibly in running the coil refrigeration plant. The cryogenic coil comprises a coil conductor for generating a magnetic field upon energization with electrical current, and refrigeration means disposed in heat conductive relation to the coil conductor for cooling to a low temperature. A substantial reduction in the power requirements for generating these magnetic fields is attained by scaling the field generating coil to large size and particular dimensions for a particular conductor, and operating the coil at a particular optimum temperature commensurate with minimum overall power requirements. (AEC)
9 CFR 3.104 - Space requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... required minimum horizontal dimension (MHD) of a pool for Group I cetaceans shall be 7.32 meters (24.0 feet... area requirements are met based on an MHD of 7.32 meters (24.0 feet) or two times the average adult... maturity. (ii) The MHD of a pool for Group II cetaceans shall be 7.32 meters (24.0 feet) or four times the...
Characterizing and contrasting instream and riparian coarse wood in western Montana basins
Michael K. Young; Ethan A. Mace; Eric T. Ziegler; Elaine K. Sutherland
2006-01-01
The importance of coarse wood to aquatic biota and stream channel structure is widely recognized, yet characterizations of large-scale patterns in coarse wood dimensions and loads are rare. To address these issues, we censused instream coarse wood ( 2 m long and 10 cm minimum diameter) and sampled riparian coarse wood and channel characteristics in and along 13 streams...
Bernard R. Parresol
1993-01-01
In the context of forest modeling, it is often reasonable to assume a multiplicative heteroscedastic error structure to the data. Under such circumstances ordinary least squares no longer provides minimum variance estimates of the model parameters. Through study of the error structure, a suitable error variance model can be specified and its parameters estimated. This...
Chen, Hui; van Eijnatten, Maureen; Wolff, Jan; de Lange, Jan; van der Stelt, Paul F; Lobbezoo, Frank; Aarab, Ghizlane
2017-08-01
The aim of this study was to assess the reliability and accuracy of three different imaging software packages for three-dimensional analysis of the upper airway using CBCT images. To assess the reliability of the software packages, 15 NewTom 5G ® (QR Systems, Verona, Italy) CBCT data sets were randomly and retrospectively selected. Two observers measured the volume, minimum cross-sectional area and the length of the upper airway using Amira ® (Visage Imaging Inc., Carlsbad, CA), 3Diagnosys ® (3diemme, Cantu, Italy) and OnDemand3D ® (CyberMed, Seoul, Republic of Korea) software packages. The intra- and inter-observer reliability of the upper airway measurements were determined using intraclass correlation coefficients and Bland & Altman agreement tests. To assess the accuracy of the software packages, one NewTom 5G ® CBCT data set was used to print a three-dimensional anthropomorphic phantom with known dimensions to be used as the "gold standard". This phantom was subsequently scanned using a NewTom 5G ® scanner. Based on the CBCT data set of the phantom, one observer measured the volume, minimum cross-sectional area, and length of the upper airway using Amira ® , 3Diagnosys ® , and OnDemand3D ® , and compared these measurements with the gold standard. The intra- and inter-observer reliability of the measurements of the upper airway using the different software packages were excellent (intraclass correlation coefficient ≥0.75). There was excellent agreement between all three software packages in volume, minimum cross-sectional area and length measurements. All software packages underestimated the upper airway volume by -8.8% to -12.3%, the minimum cross-sectional area by -6.2% to -14.6%, and the length by -1.6% to -2.9%. All three software packages offered reliable volume, minimum cross-sectional area and length measurements of the upper airway. The length measurements of the upper airway were the most accurate results in all software packages. All software packages underestimated the upper airway dimensions of the anthropomorphic phantom.
NASA Astrophysics Data System (ADS)
Madami, Marco; Gubbiotti, Gianluca; Tacchi, Silvia; Carlotti, Giovanni
2017-11-01
Single- or multi-layered planar magnetic dots, with lateral dimensions ranging from tens to hundreds of nanometers, are used as elemental switches in current and forthcoming devices for information and communication technology (ICT), including magnetic memories, spin-torque oscillators and nano-magnetic logic gates. In this review article, we will first discuss energy dissipation during irreversible switching protocols of dots of different dimensions, ranging from a few tens of nanometers to the micrometric range. Then we will focus on the fundamental energy limits of adiabatic (slow) erasure and reversal of a magnetic nanodot, showing that dissipationless operation is achievable, provided that both dynamic reversibility (arbitrarily slow application of external fields) and entropic reversibility (no free entropy increase) are insured. However, recent theoretical and experimental tests of magnetic-dot erasure reveal that intrinsic defects related to materials imperfections such as roughness or polycrystallinity, may cause an excess of dissipation if compared to the minimum theoretical limit. We will conclude providing an outlook on the most promising strategies to achieve a new generation of power-saving nanomagnetic logic devices based on clusters of interacting dots and on straintronics.
Effects of eccentricities and lateral pressure on the design of stiffened compression panels
NASA Technical Reports Server (NTRS)
Giles, G. L.; Anderson, M. S.
1972-01-01
An analysis for determining the effects of eccentricities and lateral pressure on the design of stiffened compression panels is presented. The four types of panel stiffeners considered are integral, zee, integral zee, and integral tee. Mass-strength curves, which give the mass of the panel necessary to carry a specified load, are given along with related design equations needed to calculate the cross-sectional dimensions of the minimum-mass-stiffened panel. The results of the study indicate that the proportions of the panels are geometrically similar to the proportions of panels designed for no eccentricity or lateral pressure, but no cross-sectional dimensions are greater, resulting in significantly increased mass. The analytical minimum-mass designs of zee-stiffened panels are compared with designs from experimentally derived charts. An assumed eccentricity of 0.001 times the length of the panel is used to correlate the analytical and experimental data. Good correlation between the experimentally derived and the analytical curves is obtained for the range of loading where materials yield governs the design. At lower loads the mass given by the analytical curve using this assumed eccentricity is greater than that given by the experimental results.
Size and mass of grit in gizzards of sandhill cranes, tundra swans, and mute swans
Franson, J. Christian; Hansen, Scott P.; Duerr, Adam E.; DeStefano, Stephen
2001-01-01
Because it has been suggested that waterbirds may ingest lost or discarded lead fishing weights as grit, we examined grit in the gizzards of Sandhill Cranes (Grus canadensis), Tundra Swans (Cygnus columbianus), and Mute Swans (Cygnus olor), three species where individuals have been poisoned by the ingestion of lead fishing weights. The greatest proportion (by mass) of grit in gizzards of Sandhill Cranes consisted of particles with a minimum dimension of 2.36-4.75 mm. Grit particles in swans were much smaller, with the most prevalent (by mass) being 0.6-1.18 mm. The greatest dimension of the largest grit particle found in cranes and swans was 17.4 mm and 14.0 mm, respectively. The U.S. Environmental Protection Agency has proposed a ban on lead fishing weights of ≤25.4 mm in any dimension. Based on the size of grit particles that we found in gizzards of Sandhill Cranes, Mute Swans, and Tundra Swans, we believe it is unlikely that individuals of those species would ingest, as grit, lead fishing weights larger than 25.4 mm in any dimension.
Zaylaa, Amira; Charara, Jamal; Girault, Jean-Marc
2015-08-01
The analysis of biomedical signals demonstrating complexity through recurrence plots is challenging. Quantification of recurrences is often biased by sojourn points that hide dynamic transitions. To overcome this problem, time series have previously been embedded at high dimensions. However, no one has quantified the elimination of sojourn points and rate of detection, nor the enhancement of transition detection has been investigated. This paper reports our on-going efforts to improve the detection of dynamic transitions from logistic maps and fetal hearts by reducing sojourn points. Three signal-based recurrence plots were developed, i.e. embedded with specific settings, derivative-based and m-time pattern. Determinism, cross-determinism and percentage of reduced sojourn points were computed to detect transitions. For logistic maps, an increase of 50% and 34.3% in sensitivity of detection over alternatives was achieved by m-time pattern and embedded recurrence plots with specific settings, respectively, and with a 100% specificity. For fetal heart rates, embedded recurrence plots with specific settings provided the best performance, followed by derivative-based recurrence plot, then unembedded recurrence plot using the determinism parameter. The relative errors between healthy and distressed fetuses were 153%, 95% and 91%. More than 50% of sojourn points were eliminated, allowing better detection of heart transitions triggered by gaseous exchange factors. This could be significant in improving the diagnosis of fetal state. Copyright © 2014 Elsevier Ltd. All rights reserved.
Experimental Study on 340GHz Wave Material Penetration Attenuation Properties
2015-07-01
wave penetrate materials, detailed are foam with dimension 52.6cm×61.6cm×0.4cm, paper dimension 52.6cm×61.6cm×0.4cm, wood board 52.6cm×66.0cm×0.42cm...paper box 52.6cm×61.6cm×0.01cm, and 8cm thickness sofa chair, 14cm human body chest, 21cm cement wall, are shown in Fig. 5. As the 0.34THz wave...insertion) comparison shown in Tab. 2, we get the foam has minimum penetration attenuation about 0.3dB, due to its low dielectric constant and tangent
Visual neuroscience before the neuron.
Wade, Nicholas J
2004-01-01
Visual neuroscience is considered to be a contemporary concern, based in large part on relating characteristics of neural functioning to visual experience. It presupposes a detailed knowledge of neural activity for which the neuron doctrine is a fundamental tenet. However, long before either the neuron doctrine had been advanced or the nerve cell had been described, attempts were made to estimate the dimensions of nerve fibres from measures of visual resolution. In the seventeenth century, the microscopes of Hooke and van Leeuwenhoek were unable to resolve structures as small as nerves adequately. However, it was not Hooke's microscope that led to an estimate of the dimensions of nerve fibres but his experiments on the limits of visual resolution. Hooke determined that a separation of one minute of arc was the minimum that could normally be seen. Descartes had earlier speculated that the retina consisted of the terminations of fibres of the optic nerve, and that their size defined the limits of what could be seen. Estimates of the diameters of nerve fibres were made on the basis of human visual acuity by Porterfield in 1738; he calculated the diameters of nerve fibres in the retina as one 7200th part of an inch (0.0035 mm), based on the resolution of one minute of arc as the minimum visible. In the same year, Jurin questioned the reliability of such estimates because of variations in visual resolution with different stimuli. The measurement of visual acuity was refined by Mayer in 1755, with dots, gratings, and grids used as stimuli. In the 1830s, Treviranus fused the microscopic and acuity approaches to determine the dimensions of nerve fibres. His indirect estimates of the dimensions of retinal fibres were close to those derived from microscopic observation. However, the suggestion that the retina consisted of terminations of nerve fibres influenced his detailed illustrations of its microscopic structure. Contrary to the situation that obtained after the microscopic structure of the retina had been established, a function of vision (acuity) was used to determine the dimensions of the structures (retinal elements) that were thought to mediate it.
On the star partition dimension of comb product of cycle and complete graph
NASA Astrophysics Data System (ADS)
Alfarisi, Ridho; Darmaji; Dafik
2017-06-01
Let G = (V, E) be a connected graphs with vertex set V (G), edge set E(G) and S ⊆ V (G). For an ordered partition Π = {S 1, S 2, S 3, …, Sk } of V (G), the representation of a vertex v ∈ V (G) with respect to Π is the k-vectors r(v|Π) = (d(v, S 1), d(v, S 2), …, d(v, Sk )), where d(v, Sk ) represents the distance between the vertex v and the set Sk , defined by d(v, Sk ) = min{d(v, x)|x ∈ Sk}. The partition Π of V (G) is a resolving partition if the k-vektors r(v|Π), v ∈ V (G) are distinct. The minimum resolving partition Π is a partition dimension of G, denoted by pd(G). The resolving partition Π = {S 1, S 2, S 3, …, Sk} is called a star resolving partition for G if it is a resolving partition and each subgraph induced by Si , 1 ≤ i ≤ k, is a star. The minimum k for which there exists a star resolving partition of V (G) is the star partition dimension of G, denoted by spd(G). Finding a star partition dimension of G is classified to be a NP-Hard problem. Furthermore, the comb product between G and H, denoted by G ⊲ H, is a graph obtained by taking one copy of G and |V (G)| copies of H and grafting the i-th copy of H at the vertex o to the i-th vertex of G. By definition of comb product, we can say that V (G ⊲ H) = {(a, u)|a ∈ V (G), u ∈ V (H)} and (a, u)(b, v) ∈ E(G ⊲ H) whenever a = b and uv ∈ E(H), or ab ∈ E(G) and u = v = o. In this paper, we will study the star partition dimension of comb product of cycle and complete graph, namely Cn ⊲ Km and Km ⊲ Cn for n ≥ 3 and m ≥ 3.
DiBona, G F; Jones, S Y; Sawin, L L
2000-09-01
Nonlinear dynamic analysis was used to examine the chaotic behavior of renal sympathetic nerve activity in conscious rats subjected to either complete baroreceptor denervation (sinoaortic and cardiac baroreceptor denervation) or induction of congestive heart failure (CHF). The peak interval sequence of synchronized renal sympathetic nerve discharge was extracted and used for analysis. In control rats, this yielded a system whose correlation dimension converged to a low value over the embedding dimension range of 10-15 and whose greatest Lyapunov exponent was positive. Complete baroreceptor denervation was associated with a decrease in the correlation dimension of the system (before 2.65 +/- 0.27, after 1.64 +/- 0.17; P < 0.01) and a reduction in chaotic behavior (greatest Lyapunov exponent: 0.201 +/- 0.008 bits/data point before, 0.177 +/- 0.004 bits/data point after, P < 0.02). CHF, a state characterized by impaired sinoaortic and cardiac baroreceptor regulation of renal sympathetic nerve activity, was associated with a similar decrease in the correlation dimension (control 3.41 +/- 0.23, CHF 2.62 +/- 0.26; P < 0.01) and a reduction in chaotic behavior (greatest Lyapunov exponent: 0.205 +/- 0.048 bits/data point control, 0.136 +/- 0.033 bits/data point CHF, P < 0.02). These results indicate that removal of sinoaortic and cardiac baroreceptor regulation of renal sympathetic nerve activity, occurring either physiologically or pathophysiologically, is associated with a decrease in the correlation dimensions of the system and a reduction in chaotic behavior.
Huang, Tao; Li, Xiao-yu; Jin, Rui; Ku, Jing; Xu, Sen-miao; Xu, Meng-ling; Wu, Zhen-zhong; Kong, De-guo
2015-04-01
The present paper put forward a non-destructive detection method which combines semi-transmission hyperspectral imaging technology with manifold learning dimension reduction algorithm and least squares support vector machine (LSSVM) to recognize internal and external defects in potatoes simultaneously. Three hundred fifteen potatoes were bought in farmers market as research object, and semi-transmission hyperspectral image acquisition system was constructed to acquire the hyperspectral images of normal external defects (bud and green rind) and internal defect (hollow heart) potatoes. In order to conform to the actual production, defect part is randomly put right, side and back to the acquisition probe when the hyperspectral images of external defects potatoes are acquired. The average spectrums (390-1,040 nm) were extracted from the region of interests for spectral preprocessing. Then three kinds of manifold learning algorithm were respectively utilized to reduce the dimension of spectrum data, including supervised locally linear embedding (SLLE), locally linear embedding (LLE) and isometric mapping (ISOMAP), the low-dimensional data gotten by manifold learning algorithms is used as model input, Error Correcting Output Code (ECOC) and LSSVM were combined to develop the multi-target classification model. By comparing and analyzing results of the three models, we concluded that SLLE is the optimal manifold learning dimension reduction algorithm, and the SLLE-LSSVM model is determined to get the best recognition rate for recognizing internal and external defects potatoes. For test set data, the single recognition rate of normal, bud, green rind and hollow heart potato reached 96.83%, 86.96%, 86.96% and 95% respectively, and he hybrid recognition rate was 93.02%. The results indicate that combining the semi-transmission hyperspectral imaging technology with SLLE-LSSVM is a feasible qualitative analytical method which can simultaneously recognize the internal and external defects potatoes and also provide technical reference for rapid on-line non-destructive detecting of the internal and external defects potatoes.
Two-point method uncertainty during control and measurement of cylindrical element diameters
NASA Astrophysics Data System (ADS)
Glukhov, V. I.; Shalay, V. V.; Radev, H.
2018-04-01
The topic of the article is devoted to the urgent problem of the reliability of technical products geometric specifications measurements. The purpose of the article is to improve the quality of parts linear sizes control by the two-point measurement method. The article task is to investigate methodical extended uncertainties in measuring cylindrical element linear sizes. The investigation method is a geometric modeling of the element surfaces shape and location deviations in a rectangular coordinate system. The studies were carried out for elements of various service use, taking into account their informativeness, corresponding to the kinematic pairs classes in theoretical mechanics and the number of constrained degrees of freedom in the datum element function. Cylindrical elements with informativity of 4, 2, 1 and θ (zero) were investigated. The uncertainties estimation of in two-point measurements was made by comparing the results of of linear dimensions measurements with the functional diameters maximum and minimum of the element material. Methodical uncertainty is formed when cylindrical elements with maximum informativeness have shape deviations of the cut and the curvature types. Methodical uncertainty is formed by measuring the element average size for all types of shape deviations. The two-point measurement method cannot take into account the location deviations of a dimensional element, so its use for elements with informativeness less than the maximum creates unacceptable methodical uncertainties in measurements of the maximum, minimum and medium linear dimensions. Similar methodical uncertainties also exist in the arbitration control of the linear dimensions of the cylindrical elements by limiting two-point gauges.
Gómez-Polo, Cristina; Montero, Javier
The aim of the present study was to describe personality traits of a sample of Spanish adults, identify the main sociodemographic factors related to personality, and assess the influence of these traits on healthy dental habits. A cross-sectional design was used with 235 subjects, all of Spanish nationality and aged between 18 and 80 years, with a minimum educational level (ie, they had completed only the minimum obligatory schooling), ensuring that none of the subjects had any psychologic disturbance. The data on five personality dimensions were recorded. Sociodemographic and behavioral standard scores (z) were studied for each personality dimension, and the scores were related to the other variables studied. A significant linear correlation was observed between the z scores of the personality factors and the sociodemographic and behavioral characteristics. The men had personalities with significantly less neuroticism, less openness, less agreeableness, and less conscientiousness than the women. In behavioral terms, those who brushed more than once a day were more agreeable (0.1 ± 0.9) than those who only brushed once a day (-0.2 ± 1.2), and smokers had higher mean scores for extroversion (0.3 ± 0.9) than did nonsmokers (-0.1 ± 1.0). The most developed personality traits in this sample, as in the reference population, were conscientiousness (123.1 ± 22.9 points) and agreeableness (119.2 ± 19.1 points). The main sociodemographic factors of personality were found to be age and sex. Moreover, it was observed that certain personality dimensions were linked to smoking and tooth brushing habits.
Chaos and Forecasting - Proceedings of the Royal Society Discussion Meeting
NASA Astrophysics Data System (ADS)
Tong, Howell
1995-04-01
The Table of Contents for the full book PDF is as follows: * Preface * Orthogonal Projection, Embedding Dimension and Sample Size in Chaotic Time Series from a Statistical Perspective * A Theory of Correlation Dimension for Stationary Time Series * On Prediction and Chaos in Stochastic Systems * Locally Optimized Prediction of Nonlinear Systems: Stochastic and Deterministic * A Poisson Distribution for the BDS Test Statistic for Independence in a Time Series * Chaos and Nonlinear Forecastability in Economics and Finance * Paradigm Change in Prediction * Predicting Nonuniform Chaotic Attractors in an Enzyme Reaction * Chaos in Geophysical Fluids * Chaotic Modulation of the Solar Cycle * Fractal Nature in Earthquake Phenomena and its Simple Models * Singular Vectors and the Predictability of Weather and Climate * Prediction as a Criterion for Classifying Natural Time Series * Measuring and Characterising Spatial Patterns, Dynamics and Chaos in Spatially-Extended Dynamical Systems and Ecologies * Non-Linear Forecasting and Chaos in Ecology and Epidemiology: Measles as a Case Study
Culture, nature and particulate matter - Hybrid reframings in air pollution scholarship
NASA Astrophysics Data System (ADS)
Cupples, Julie
Air pollution is a thoroughly hybrid phenomenon. It is composed of inseparable physical, scientific, cultural, social, economic and political dimensions. It is both an object of environmental science and embedded in our everyday social and cultural worlds. Nevertheless, much air pollution scholarship focuses solely on the physical dimensions of air pollution which are expressed quantitatively and pays little or no regard to the identities, discourses, bodies and emotions which constitute and are constituted by air pollution as a physical reality. This article argues for a more reflexive and hybrid approach to air pollution research which bridges intellectually confining binaries. Drawing on the work of Bruno Latour and other actor-network theorists, it argues that if we can let go of a foundational nature, disrupt our humanism and take non-scientific knowledges seriously, we might develop a new respect for the atmospheric environment and begin the task of building a better common world.
On iterative processes in the Krylov-Sonneveld subspaces
NASA Astrophysics Data System (ADS)
Ilin, Valery P.
2016-10-01
The iterative Induced Dimension Reduction (IDR) methods are considered for solving large systems of linear algebraic equations (SLAEs) with nonsingular nonsymmetric matrices. These approaches are investigated by many authors and are charachterized sometimes as the alternative to the classical processes of Krylov type. The key moments of the IDR algorithms consist in the construction of the embedded Sonneveld subspaces, which have the decreasing dimensions and use the orthogonalization to some fixed subspace. Other independent approaches for research and optimization of the iterations are based on the augmented and modified Krylov subspaces by using the aggregation and deflation procedures with present various low rank approximations of the original matrices. The goal of this paper is to show, that IDR method in Sonneveld subspaces present an original interpretation of the modified algorithms in the Krylov subspaces. In particular, such description is given for the multi-preconditioned semi-conjugate direction methods which are actual for the parallel algebraic domain decomposition approaches.
On solving three-dimensional open-dimension rectangular packing problems
NASA Astrophysics Data System (ADS)
Junqueira, Leonardo; Morabito, Reinaldo
2017-05-01
In this article, a recently proposed three-dimensional open-dimension rectangular packing problem is considered, in which the objective is to find a minimal volume rectangular container that packs a set of rectangular boxes. The literature has tackled small-sized instances of this problem by means of optimization solvers, position-free mixed-integer programming (MIP) formulations and piecewise linearization approaches. In this study, the problem is alternatively addressed by means of grid-based position MIP formulations, whereas still considering optimization solvers and the same piecewise linearization techniques. A comparison of the computational performance of both models is then presented, when tested with benchmark problem instances and with new instances, and it is shown that the grid-based position MIP formulation can be competitive, depending on the characteristics of the instances. The grid-based position MIP formulation is also embedded with real-world practical constraints, such as cargo stability, and results are additionally presented.
Occupation, well-being, and culture: Theory and cultural humility.
Hammell, Karen R Whalley
2013-10-01
The Canadian Model of Occupational Performance and Engagement depicts individuals embedded within cultural environments that afford occupational possibilities. Culture pertains not solely to ethnicity or race but to any dimension of diversity, including class, gender, sexual orientation, and ability. This paper highlights specific dimensions of cultural diversity and their relationships to occupational engagement and well-being. Cultural variations constitute the basis for a socially constructed hierarchy of traits that significantly determine occupational opportunities and impact mental health and well-being. Cultural humility is an approach to redressing power imbalances in client-therapist relationships by incorporating critical self-evaluation and recognizing that cultural differences lie not within clients but within client-therapist relationships. It is proposed that theoretical relevance would be enhanced if culturally diverse perspectives were incorporated into theories of occupation. Cultural humility is advocated as an approach to theoretical development and in efforts to counter professional Eurocentrism, ethnocentrism, and intellectual colonialism.
A no-go theorem for monodromy inflation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Andriot, David, E-mail: david.andriot@aei.mpg.de
2016-03-01
We study the embedding of the monodromy inflation mechanism by E. Silverstein and A. Westphal (2008) in a concrete compactification setting. To that end, we look for an appropriate vacuum of type IIA supergravity, corresponding to the minimum of the inflaton potential. We prove a no-go theorem on the existence of such a vacuum, using ten-dimensional equations of motion. Anti-de Sitter and Minkowski vacua are ruled out; de Sitter vacua are not excluded, but have a lower bound on their cosmological constant which is too high for phenomenology.
A Hybrid Metaheuristic DE/CS Algorithm for UCAV Three-Dimension Path Planning
Wang, Gaige; Guo, Lihong; Duan, Hong; Wang, Heqi; Liu, Luo; Shao, Mingzhen
2012-01-01
Three-dimension path planning for uninhabited combat air vehicle (UCAV) is a complicated high-dimension optimization problem, which primarily centralizes on optimizing the flight route considering the different kinds of constrains under complicated battle field environments. A new hybrid metaheuristic differential evolution (DE) and cuckoo search (CS) algorithm is proposed to solve the UCAV three-dimension path planning problem. DE is applied to optimize the process of selecting cuckoos of the improved CS model during the process of cuckoo updating in nest. The cuckoos can act as an agent in searching the optimal UCAV path. And then, the UCAV can find the safe path by connecting the chosen nodes of the coordinates while avoiding the threat areas and costing minimum fuel. This new approach can accelerate the global convergence speed while preserving the strong robustness of the basic CS. The realization procedure for this hybrid metaheuristic approach DE/CS is also presented. In order to make the optimized UCAV path more feasible, the B-Spline curve is adopted for smoothing the path. To prove the performance of this proposed hybrid metaheuristic method, it is compared with basic CS algorithm. The experiment shows that the proposed approach is more effective and feasible in UCAV three-dimension path planning than the basic CS model. PMID:23193383
A hybrid metaheuristic DE/CS algorithm for UCAV three-dimension path planning.
Wang, Gaige; Guo, Lihong; Duan, Hong; Wang, Heqi; Liu, Luo; Shao, Mingzhen
2012-01-01
Three-dimension path planning for uninhabited combat air vehicle (UCAV) is a complicated high-dimension optimization problem, which primarily centralizes on optimizing the flight route considering the different kinds of constrains under complicated battle field environments. A new hybrid metaheuristic differential evolution (DE) and cuckoo search (CS) algorithm is proposed to solve the UCAV three-dimension path planning problem. DE is applied to optimize the process of selecting cuckoos of the improved CS model during the process of cuckoo updating in nest. The cuckoos can act as an agent in searching the optimal UCAV path. And then, the UCAV can find the safe path by connecting the chosen nodes of the coordinates while avoiding the threat areas and costing minimum fuel. This new approach can accelerate the global convergence speed while preserving the strong robustness of the basic CS. The realization procedure for this hybrid metaheuristic approach DE/CS is also presented. In order to make the optimized UCAV path more feasible, the B-Spline curve is adopted for smoothing the path. To prove the performance of this proposed hybrid metaheuristic method, it is compared with basic CS algorithm. The experiment shows that the proposed approach is more effective and feasible in UCAV three-dimension path planning than the basic CS model.
Optimization of micromachined membrane switches
NASA Astrophysics Data System (ADS)
Hiltmann, Kai; Lang, Walter
1997-09-01
We have determined the minimum dimensions for micromachined membrane switches in several experiments, both regarding the strength of the membranes themselves and the elongations required for safe switching performance. Based on these data, pressure switches for voltages of 10 - 100 V were made as single and multiple elements and tested. Test results, with scatter of pressure threshold data in the ten per cent range, prove very encouraging for further development.
Bouma, Helen; López López, Mónica; Knorth, Erik J; Grietens, Hans
2018-05-01
Policymakers are increasingly focusing on the participation of children in the child protection system (CPS). However, research shows that actual practice still needs to be improved. Embedding children's participation in legislation and policy documents is one important prerequisite for achieving meaningful participation in child protection practice. In this study, the participation of children in the Dutch CPS under the new Youth Act 2015 is critically analyzed. National legislation and policy documents were studied using a model of "meaningful participation" based on article 12 of the UNCRC. Results show that the idea of children's participation is deeply embedded in the current Dutch CPS. However, Dutch policy documents do not fully cover the three dimensions of what is considered to be meaningful participation for children: informing, hearing, and involving. Furthermore, children's participation differs among the organizations included in the child protection chain. A clear overall policy concerning the participation of children in the Dutch CPS is lacking. The conclusions of this critical analysis of policy documents and the framework of meaningful participation presented may provide a basis for the embedding of meaningful participation for children in child protection systems of other countries. Copyright © 2018 Elsevier Ltd. All rights reserved.
Overview on Techniques to Construct Tissue Arrays with Special Emphasis on Tissue Microarrays
Vogel, Ulrich
2014-01-01
With the advent of new histopathological staining techniques (histochemistry, immunohistochemistry, in situ hybridization) and the discovery of thousands of new genes, mRNA, and proteins by molecular biology, the need grew for a technique to compare many different cells or tissues on one slide in a cost effective manner and with the possibility to easily track the identity of each specimen: the tissue array (TA). Basically, a TA consists of at least two different specimens per slide. TAs differ in the kind of specimens, the number of specimens installed, the dimension of the specimens, the arrangement of the specimens, the embedding medium, the technique to prepare the specimens to be installed, and the technique to construct the TA itself. A TA can be constructed by arranging the tissue specimens in a mold and subsequently pouring the mold with the embedding medium of choice. In contrast, preformed so-called recipient blocks consisting of the embedding medium of choice have punched, drilled, or poured holes of different diameters and distances in which the cells or tissue biopsies will be deployed manually, semi-automatically, or automatically. The costs of constructing a TA differ from a few to thousands of Euros depending on the technique/equipment used. Remarkably high quality TAs can be also achieved by low cost techniques. PMID:27600339
Unsupervised image matching based on manifold alignment.
Pei, Yuru; Huang, Fengchun; Shi, Fuhao; Zha, Hongbin
2012-08-01
This paper challenges the issue of automatic matching between two image sets with similar intrinsic structures and different appearances, especially when there is no prior correspondence. An unsupervised manifold alignment framework is proposed to establish correspondence between data sets by a mapping function in the mutual embedding space. We introduce a local similarity metric based on parameterized distance curves to represent the connection of one point with the rest of the manifold. A small set of valid feature pairs can be found without manual interactions by matching the distance curve of one manifold with the curve cluster of the other manifold. To avoid potential confusions in image matching, we propose an extended affine transformation to solve the nonrigid alignment in the embedding space. The comparatively tight alignments and the structure preservation can be obtained simultaneously. The point pairs with the minimum distance after alignment are viewed as the matchings. We apply manifold alignment to image set matching problems. The correspondence between image sets of different poses, illuminations, and identities can be established effectively by our approach.
A dynamic modelling framework towards the solution of reduction in smoking prevalence
NASA Astrophysics Data System (ADS)
Halim, Tisya Farida Abdul; Sapiri, Hasimah; Abidin, Norhaslinda Zainal
2016-10-01
This paper presents a hypothetical framework towards the solution for reduction in smoking prevalence in Malaysia. The framework is design to assist in decision making process related to reduction in smoking prevalence using SD and OCT. In general, this framework is developed using SD approach where OCT is embedded in the policy evaluation process. Smoking prevalence is one of the determinant which plays an important role in measuring a successful implementation of anti-smoking strategies. Therefore, it is critical to determine the optimal value of smoking prevalence in order to trim down the hazardous effects of smoking to society. Conversely, smoking problem becomes increasingly complex since many issues that ranged from behavioral to economical need to be considered simultaneously. Thus, a hypothetical framework of the control model embedded in the SD methodology is expected to obtain the minimum value of smoking prevalence which the output in turn will provide a guideline for tobacco researchers as well as decision makers for policy design and evaluation.
The effect of patterning options on embedded memory cells in logic technologies at iN10 and iN7
NASA Astrophysics Data System (ADS)
Appeltans, Raf; Weckx, Pieter; Raghavan, Praveen; Kim, Ryoung-Han; Kar, Gouri Sankar; Furnémont, Arnaud; Van der Perre, Liesbet; Dehaene, Wim
2017-03-01
Static Random Access Memory (SRAM) cells are used together with logic standard cells as the benchmark to develop the process flow for new logic technologies. In order to achieve successful integration of Spin-Transfer Torque Magnetic Random Access Memory (STT-MRAM) as area efficient higher level embedded cache, it also needs to be included as a benchmark. The simple cell structure of STT-MRAM brings extra patterning challenges to achieve high density. The two memory types are compared in terms of minimum area and critical design rules in both the iN10 and iN7 node, with an extra focus on patterning options in iN7. Both the use of Self-Aligned Quadruple Patterning (SAQP) mandrel and spacer engineering, as well as multi-level via's are explored. These patterning options result in large area gains for the STT-MRAM cell and moreover determine which cell variant is the smallest.
A fourth-order Cartesian grid embeddedboundary method for Poisson’s equation
Devendran, Dharshi; Graves, Daniel; Johansen, Hans; ...
2017-05-08
In this paper, we present a fourth-order algorithm to solve Poisson's equation in two and three dimensions. We use a Cartesian grid, embedded boundary method to resolve complex boundaries. We use a weighted least squares algorithm to solve for our stencils. We use convergence tests to demonstrate accuracy and we show the eigenvalues of the operator to demonstrate stability. We compare accuracy and performance with an established second-order algorithm. We also discuss in depth strategies for retaining higher-order accuracy in the presence of nonsmooth geometries.
A fourth-order Cartesian grid embeddedboundary method for Poisson’s equation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Devendran, Dharshi; Graves, Daniel; Johansen, Hans
In this paper, we present a fourth-order algorithm to solve Poisson's equation in two and three dimensions. We use a Cartesian grid, embedded boundary method to resolve complex boundaries. We use a weighted least squares algorithm to solve for our stencils. We use convergence tests to demonstrate accuracy and we show the eigenvalues of the operator to demonstrate stability. We compare accuracy and performance with an established second-order algorithm. We also discuss in depth strategies for retaining higher-order accuracy in the presence of nonsmooth geometries.
NASA Technical Reports Server (NTRS)
Gatski, T. B.; Grosch, C. E.
1984-01-01
A compact finite-difference approximation to the unsteady Navier-Stokes equations in velocity-vorticity variables is used to numerically simulate a number of flows. These include two-dimensional laminar flow of a vortex evolving over a flat plate with an embedded cavity, the unsteady flow over an elliptic cylinder, and aspects of the transient dynamics of the flow over a rearward facing step. The methodology required to extend the two-dimensional formulation to three-dimensions is presented.
Photon orbits and thermodynamic phase transition of d -dimensional charged AdS black holes
NASA Astrophysics Data System (ADS)
Wei, Shao-Wen; Liu, Yu-Xiao
2018-05-01
We study the relationship between the null geodesics and thermodynamic phase transition for the charged AdS black hole. In the reduced parameter space, we find that there exist nonmonotonic behaviors of the photon sphere radius and the minimum impact parameter for the pressure below its critical value. The study also shows that the changes of the photon sphere radius and the minimum impact parameter can serve as order parameters for the small-large black hole phase transition. In particular, these changes have an universal exponent of 1/2 near the critical point for any dimension d of spacetime. These results imply that there may exist universal critical behavior of gravity near the thermodynamic critical point of the black hole system.
Uncertainty relation for the discrete Fourier transform.
Massar, Serge; Spindel, Philippe
2008-05-16
We derive an uncertainty relation for two unitary operators which obey a commutation relation of the form UV=e(i phi) VU. Its most important application is to constrain how much a quantum state can be localized simultaneously in two mutually unbiased bases related by a discrete fourier transform. It provides an uncertainty relation which smoothly interpolates between the well-known cases of the Pauli operators in two dimensions and the continuous variables position and momentum. This work also provides an uncertainty relation for modular variables, and could find applications in signal processing. In the finite dimensional case the minimum uncertainty states, discrete analogues of coherent and squeezed states, are minimum energy solutions of Harper's equation, a discrete version of the harmonic oscillator equation.
Koshka, Yaroslav; Perera, Dilina; Hall, Spencer; Novotny, M A
2017-07-01
The possibility of using a quantum computer D-Wave 2X with more than 1000 qubits to determine the global minimum of the energy landscape of trained restricted Boltzmann machines is investigated. In order to overcome the problem of limited interconnectivity in the D-Wave architecture, the proposed RBM embedding combines multiple qubits to represent a particular RBM unit. The results for the lowest-energy (the ground state) and some of the higher-energy states found by the D-Wave 2X were compared with those of the classical simulated annealing (SA) algorithm. In many cases, the D-Wave machine successfully found the same RBM lowest-energy state as that found by SA. In some examples, the D-Wave machine returned a state corresponding to one of the higher-energy local minima found by SA. The inherently nonperfect embedding of the RBM into the Chimera lattice explored in this work (i.e., multiple qubits combined into a single RBM unit were found not to be guaranteed to be all aligned) and the existence of small, persistent biases in the D-Wave hardware may cause a discrepancy between the D-Wave and the SA results. In some of the investigated cases, introduction of a small bias field into the energy function or optimization of the chain-strength parameter in the D-Wave embedding successfully addressed difficulties of the particular RBM embedding. With further development of the D-Wave hardware, the approach will be suitable for much larger numbers of RBM units.
Bulk locality and boundary creating operators
Nakayama, Yu; Ooguri, Hirosi
2015-10-19
Here, we formulate a minimum requirement for CFT operators to be localized in the dual AdS. In any spacetime dimensions, we show that a general solution to the requirement is a linear superposition of operators creating spherical boundaries in CFT, with the dilatation by the imaginary unit from their centers. This generalizes the recent proposal by Miyaji et al. for bulk local operators in the three dimensional AdS. We show that Ishibashi states for the global conformal symmetry in any dimensions and with the imaginary di-latation obey free field equations in AdS and that incorporating bulk interactions require their superpositions.more » We also comment on the recent proposals by Kabat et al., and by H. Verlinde.« less
A Possible Cause of the Diminished Solar Wind During the Solar Cycle 23 - 24 Minimum
NASA Astrophysics Data System (ADS)
Liou, Kan; Wu, Chin-Chun
2016-12-01
Interplanetary magnetic field and solar wind plasma density observed at 1 AU during Solar Cycle 23 - 24 (SC-23/24) minimum were significantly smaller than those during its previous solar cycle (SC-22/23) minimum. Because the Earth's orbit is embedded in the slow wind during solar minimum, changes in the geometry and/or content of the slow wind region (SWR) can have a direct influence on the solar wind parameters near the Earth. In this study, we analyze solar wind plasma and magnetic field data of hourly values acquired by Ulysses. It is found that the solar wind, when averaging over the first (1995.6 - 1995.8) and third (2006.9 - 2008.2) Ulysses' perihelion ({˜} 1.4 AU) crossings, was about the same speed, but significantly less dense ({˜} 34 %) and cooler ({˜} 20 %), and the total magnetic field was {˜} 30 % weaker during the third compared to the first crossing. It is also found that the SWR was {˜} 50 % wider in the third ({˜} 68.5^deg; in heliographic latitude) than in the first ({˜} 44.8°) solar orbit. The observed latitudinal increase in the SWR is sufficient to explain the excessive decline in the near-Earth solar wind density during the recent solar minimum without speculating that the total solar output may have been decreasing. The observed SWR inflation is also consistent with a cooler solar wind in the SC-23/24 than in the SC-22/23 minimum. Furthermore, the ratio of the high-to-low latitude photospheric magnetic field (or equatorward magnetic pressure force), as observed by the Mountain Wilson Observatory, is smaller during the third than the first Ulysses' perihelion orbit. These findings suggest that the smaller equatorward magnetic pressure at the Sun may have led to the latitudinally-wider SRW observed by Ulysses in SC-23/24 minimum.
Lorentz violation with a universal minimum speed as foundation of de Sitter relativity
NASA Astrophysics Data System (ADS)
Cruz, Cláudio Nassif; Dos Santos, Rodrigo Francisco; Amaro de Faria, A. C.
We aim to investigate the theory of Lorentz violation with an invariant minimum speed called Symmetrical Special Relativity (SSR) from the viewpoint of its metric. Thus, we should explore the nature of SSR-metric in order to understand the origin of the conformal factor that appears in the metric by deforming Minkowski metric by means of an invariant minimum speed that breaks down Lorentz symmetry. So, we are able to realize that there is a similarity between SSR and a new space with variable negative curvature ( -∞ < ℛ < 0) connected to a set of infinite cosmological constants (0 < Λ < ∞), working like an extended de Sitter (dS) relativity, so that such extended dS-relativity has curvature and cosmological “constant” varying in time. We obtain a scenario that is more similar to dS-relativity given in the approximation of a slightly negative curvature for representing the current universe having a tiny cosmological constant. Finally, we show that the invariant minimum speed provides the foundation for understanding the kinematics origin of the extra dimension considered in dS-relativity in order to represent the dS-length.
Genetics algorithm optimization of DWT-DCT based image Watermarking
NASA Astrophysics Data System (ADS)
Budiman, Gelar; Novamizanti, Ledya; Iwut, Iwan
2017-01-01
Data hiding in an image content is mandatory for setting the ownership of the image. Two dimensions discrete wavelet transform (DWT) and discrete cosine transform (DCT) are proposed as transform method in this paper. First, the host image in RGB color space is converted to selected color space. We also can select the layer where the watermark is embedded. Next, 2D-DWT transforms the selected layer obtaining 4 subband. We select only one subband. And then block-based 2D-DCT transforms the selected subband. Binary-based watermark is embedded on the AC coefficients of each block after zigzag movement and range based pixel selection. Delta parameter replacing pixels in each range represents embedded bit. +Delta represents bit “1” and -delta represents bit “0”. Several parameters to be optimized by Genetics Algorithm (GA) are selected color space, layer, selected subband of DWT decomposition, block size, embedding range, and delta. The result of simulation performs that GA is able to determine the exact parameters obtaining optimum imperceptibility and robustness, in any watermarked image condition, either it is not attacked or attacked. DWT process in DCT based image watermarking optimized by GA has improved the performance of image watermarking. By five attacks: JPEG 50%, resize 50%, histogram equalization, salt-pepper and additive noise with variance 0.01, robustness in the proposed method has reached perfect watermark quality with BER=0. And the watermarked image quality by PSNR parameter is also increased about 5 dB than the watermarked image quality from previous method.
Shapes of Soot Particles Embedded in Organic Material and Sulfates
NASA Astrophysics Data System (ADS)
Adachi, K.; Buseck, P. R.
2008-12-01
Three-dimensional (3D) shapes of aerosol particles collected from Mexico City during the MILAGRO (Megacity Initiative: Local and Global Research Observations) campaign were analyzed using electron tomography (ET). Mexico City is a representative tropical megacity, where pollution is heavy and photochemical reaction is rapid. Its aerosol particles are of interest because of their effects on the regional and global climate and on health. We used ET to study soot particles that are embedded in organic material, commonly with sulfates, collected from Mexico City plumes. They comprise more than 50 % of the aerosol particles with aerodynamic diameters between 50 and 300 nm. ET combines a series of transmission electron microscope (TEM) images obtained in different viewing directions into representations that display the 3D digitized objects. By using the 3D data, we determined the volume ratios of the various component materials in individual internally mixed particles. In our samples, organic materials dominate, and soot and sulfate commonly occupy up to 10 volume %. The mean fractal dimension, which indicates the complexity of aggregates, of soot particles is 2.2 (± 0.2), suggesting that they retain their chain-like structure when embedded in organic material rather than being highly compacted. Their 3D images show that soot particles tend to be near the surface of the embedding particle rather than in the core, i.e., a core-shell model is inappropriate. Their morphological features indicate that the soot particles have lower absorption of sunlight by a few tens of percent relative to that of the compacted or concentrically coated particles assumed in current climate models.
Nuclear reactor fuel structure containing uranium alloy wires embedded in a metallic matrix plate
Travelli, A.
1985-10-25
A flat or curved plate structure, to be used as fuel in a nuclear reactor, comprises elongated fissionable wires or strips embedded in a metallic continuous non-fissionable matrix plate. The wires or strips are made predominantly of a malleable uranium alloy, such as uranium silicide, uranium gallide or uranium germanide. The matrix plate is made predominantly of aluminum or an aluminum alloy. The wires or strips are located in a single row at the midsurface of the plate, parallel with one another and with the length dimension of the plate. The wires or strips are separated from each other, and from the surface of the plate, by sufficient thicknesses of matrix material, to provide structural integrity and effective fission product retention, under neutron irradiation. This construction makes it safely feasible to provide a high uranium density, so that the uranium enrichment with uranium 235 may be reduced below about 20%, to deter the reprocessing of the uranium for use in nuclear weapons.
Nuclear reactor fuel structure containing uranium alloy wires embedded in a metallic matrix plate
Travelli, Armando
1988-01-01
A flat or curved plate structure, to be used as fuel in a nuclear reactor, comprises elongated fissionable wires or strips embedded in a metallic continuous non-fissionable matrix plate. The wires or strips are made predominantly of a malleable uranium alloy, such as uranium silicide, uranium gallide or uranium germanide. The matrix plate is made predominantly of aluminum or an aluminum alloy. The wires or strips are located in a single row at the midsurface of the plate, parallel with one another and with the length dimension of the plate. The wires or strips are separated from each other, and from the surface of the plate, by sufficient thicknesses of matrix material, to provide structural integrity and effective fission product retention, under neutron irradiation. This construction makes it safely feasible to provide a high uranium density, so that the uranium enrichment with uranium 235 may be reduced below about 20%, to deter the reprocessing of the uranium for use in nuclear weapons.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Palmkvist, Jakob, E-mail: palmkvist@ihes.fr
We introduce an infinite-dimensional Lie superalgebra which is an extension of the U-duality Lie algebra of maximal supergravity in D dimensions, for 3 ⩽ D ⩽ 7. The level decomposition with respect to the U-duality Lie algebra gives exactly the tensor hierarchy of representations that arises in gauge deformations of the theory described by an embedding tensor, for all positive levels p. We prove that these representations are always contained in those coming from the associated Borcherds-Kac-Moody superalgebra, and we explain why some of the latter representations are not included in the tensor hierarchy. The most remarkable feature of ourmore » Lie superalgebra is that it does not admit a triangular decomposition like a (Borcherds-)Kac-Moody (super)algebra. Instead the Hodge duality relations between level p and D − 2 − p extend to negative p, relating the representations at the first two negative levels to the supersymmetry and closure constraints of the embedding tensor.« less
Domínguez, Jorge Bouza; Bérubé-Lauzière, Yves
2011-01-01
We introduce a system of coupled time-dependent parabolic simplified spherical harmonic equations to model the propagation of both excitation and fluorescence light in biological tissues. We resort to a finite element approach to obtain the time-dependent profile of the excitation and the fluorescence light fields in the medium. We present results for cases involving two geometries in three-dimensions: a homogeneous cylinder with an embedded fluorescent inclusion and a realistically-shaped rodent with an embedded inclusion alike an organ filled with a fluorescent probe. For the cylindrical geometry, we show the differences in the time-dependent fluorescence response for a point-like, a spherical, and a spherically Gaussian distributed fluorescent inclusion. From our results, we conclude that the model is able to describe the time-dependent excitation and fluorescent light transfer in small geometries with high absorption coefficients and in nondiffusive domains, as may be found in small animal diffuse optical tomography (DOT) and fluorescence DOT imaging. PMID:21483606
The Effect of Different Shape and Perforated rHDPE in Concrete Structures on Flexural Strength
NASA Astrophysics Data System (ADS)
Yuhazri, MY; Hafiz, KM; Myia, YZA; Jia, CP; Sihombing, H.; Sapuan, SM; Badarulzaman, NA
2017-10-01
This research was carried out to develop a reinforcing structure from recycled HDPE plastic lubricant containers to be embedded in concrete structure. Different forms and shapes of recycled HDPE plastic are designed as reinforcement incorporate with cement. In this study, the reinforcing structure was prepared by washing, cutting, dimensioning and joining of the waste HDPE containers (direct technique without treatment on plastic surface). Then, the rHDPE reinforced concrete was produced by casting based on standard of procedure in civil engineering technique. Eight different shapes of rHDPE in concrete structure were used to determine the concrete’s ability in terms of flexural strength. Embedded round shape in solid and perforated of rHDPE in concrete system drastically improved flexural strength at 17.78 % and 13.79 %. The result would seem that the concrete with reinforcing rHDPE structure exhibits a more gradual or flexible properties than concrete beams without reinforcement that has the properties of fragile.
NASA Astrophysics Data System (ADS)
Bowen, David; Krafft, Charles; Mayergoyz, Isaak D.
2017-05-01
There is strong commercial interest in the ability to fabricate the windings of traditional miniature wire-wound inductive circuit components, such as Ethernet transformers, lithographically. For greater inductance devices, thick cores are required, making the process of embedding the ferrite material within circuit board one of few options for lithographic winding fabrication. In this paper, a non-traditional core shape, suitable for embedding in circuit board, is examined analytically and experimentally; the racetrack shape is two halves of a toroid connected by straight legs. With regard to the high inductance requirements for Ethernet applications (350μH), the racetrack transformer inductance is analytically optimized, determining the optimal physical dimensions. Two sizes of racetrack-core transformers were fabricated and measured. The measured inductance was in reasonable agreement with the analytical prediction, though large variations in material permeability are expected from the mechanical processing of the ferrite. Some of the experimental transformers were observed to satisfy the Ethernet inductance requirement.
Bonetto, Rita Dominga; Ladaga, Juan Luis; Ponz, Ezequiel
2006-04-01
Scanning electron microscopy (SEM) is widely used in surface studies and continuous efforts are carried out in the search of estimators of different surface characteristics. By using the variogram, we developed two of these estimators that were used to characterize the surface roughness from the SEM image texture. One of the estimators is related to the crossover between fractal region at low scale and the periodic region at high scale, whereas the other estimator characterizes the periodic region. In this work, a full study of these estimators and the fractal dimension in two dimensions (2D) and three dimensions (3D) was carried out for emery papers. We show that the obtained fractal dimension with only one image is good enough to characterize the roughness surface because its behavior is similar to those obtained with 3D height data. We show also that the estimator that indicates the crossover is related to the minimum cell size in 2D and to the average particle size in 3D. The other estimator has different values for the three studied emery papers in 2D but it does not have a clear meaning, and these values are similar for those studied samples in 3D. Nevertheless, it indicates the formation tendency of compound cells. The fractal dimension values from the variogram and from an area versus step log-log graph were studied with 3D data. Both methods yield different values corresponding to different information from the samples.
NASA Astrophysics Data System (ADS)
Zhang, Peng; Peng, Jing; Sims, S. Richard F.
2005-05-01
In ATR applications, each feature is a convolution of an image with a filter. It is important to use most discriminant features to produce compact representations. We propose two novel subspace methods for dimension reduction to address limitations associated with Fukunaga-Koontz Transform (FKT). The first method, Scatter-FKT, assumes that target is more homogeneous, while clutter can be anything other than target and anywhere. Thus, instead of estimating a clutter covariance matrix, Scatter-FKT computes a clutter scatter matrix that measures the spread of clutter from the target mean. We choose dimensions along which the difference in variation between target and clutter is most pronounced. When the target follows a Gaussian distribution, Scatter-FKT can be viewed as a generalization of FKT. The second method, Optimal Bayesian Subspace, is derived from the optimal Bayesian classifier. It selects dimensions such that the minimum Bayes error rate can be achieved. When both target and clutter follow Gaussian distributions, OBS computes optimal subspace representations. We compare our methods against FKT using character image as well as IR data.
Influence of Turbulent Flow and Fractal Scaling on Effective Permeability of Fracture Network
NASA Astrophysics Data System (ADS)
Zhu, J.
2017-12-01
A new approach is developed to calculate hydraulic gradient dependent effective permeability of a fractal fracture network where both laminar and turbulent flows may occur in individual fractures. A critical fracture length is used to distinguish flow characteristics in individual fractures. The developed new solutions can be used for the case of a general scaling relationship, an extension to the linear scaling. We examine the impact on the effective permeability of the network of fractal fracture network characteristics, which include the fractal scaling coefficient and exponent, fractal dimension, ratio of minimum over maximum fracture lengths. Results demonstrate that the developed solution can explain more variations of the effective permeability in relation to the fractal dimensions estimated from the field observations. At high hydraulic gradient the effective permeability decreases with the fractal scaling exponent, but increases with the fractal scaling exponent at low gradient. The effective permeability increases with the scaling coefficient, fractal dimension, fracture length ratio and maximum fracture length.
Kaluza-Klein two-brane-worlds cosmology at low energy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feranie, S.; Arianto; Zen, Freddy P.
2010-04-15
We study two (4+n)-dimensional branes embedded in (5+n)-dimensional spacetime. Using the gradient expansion approximation, we find that the effective theory is described by (4+n)-dimensional scalar-tensor gravity with a specific coupling function. Based on this theory we investigate the Kaluza-Klein two-brane-worlds cosmology at low energy, in both the static and the nonstatic internal dimensions. In the case of the static internal dimensions, the effective gravitational constant in the induced Friedmann equation depends on the equations of state of the brane matter, and the dark radiation term naturally appears. In the nonstatic case we take a relation between the external and internalmore » scale factors of the form b(t)=a{sup {gamma}(t)} in which the brane world evolves with two scale factors. In this case, the induced Friedmann equation on the brane is modified in the effective gravitational constant and the term proportional to a{sup -4{beta}.} For dark radiation, we find {gamma}=-2/(1+n). Finally, we discuss the issue of conformal frames which naturally arises with scalar-tensor theories. We find that the static internal dimensions in the Jordan frame may become nonstatic in the Einstein frame.« less
Decoding-Accuracy-Based Sequential Dimensionality Reduction of Spatio-Temporal Neural Activities
NASA Astrophysics Data System (ADS)
Funamizu, Akihiro; Kanzaki, Ryohei; Takahashi, Hirokazu
Performance of a brain machine interface (BMI) critically depends on selection of input data because information embedded in the neural activities is highly redundant. In addition, properly selected input data with a reduced dimension leads to improvement of decoding generalization ability and decrease of computational efforts, both of which are significant advantages for the clinical applications. In the present paper, we propose an algorithm of sequential dimensionality reduction (SDR) that effectively extracts motor/sensory related spatio-temporal neural activities. The algorithm gradually reduces input data dimension by dropping neural data spatio-temporally so as not to undermine the decoding accuracy as far as possible. Support vector machine (SVM) was used as the decoder, and tone-induced neural activities in rat auditory cortices were decoded into the test tone frequencies. SDR reduced the input data dimension to a quarter and significantly improved the accuracy of decoding of novel data. Moreover, spatio-temporal neural activity patterns selected by SDR resulted in significantly higher accuracy than high spike rate patterns or conventionally used spatial patterns. These results suggest that the proposed algorithm can improve the generalization ability and decrease the computational effort of decoding.
Energy-momentum tensor of bouncing gravitons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Iofa, Mikhail Z.
2015-07-14
In models of the Universe with extra dimensions gravity propagates in the whole space-time. Graviton production by matter on the brane is significant in the early hot Universe. In a model of 3-brane with matter embedded in 5D space-time conditions for gravitons emitted from the brane to the bulk to return back to the brane are found. For a given 5-momentum of graviton falling back to the brane the interval between the times of emission and return to the brane is calculated. A method to calculate contribution to the energy-momentum tensor from multiple graviton bouncings is developed. Explicit expressions formore » contributions to the energy-momentum tensor of gravitons which have made one, two and three bounces are obtained and their magnitudes are numerically calculated. These expressions are used to solve the evolution equation for dark radiation. A relation connecting reheating temperature and the scale of extra dimension is obtained. For the reheating temperature T{sub R}∼10{sup 6} GeV we estimate the scale of extra dimension μ to be of order 10{sup −9} GeV (μ{sup −1}∼10{sup −5} cm)« less
Energy-momentum tensor of bouncing gravitons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Iofa, Mikhail Z., E-mail: iofa@theory.sinp.msu.ru
2015-07-01
In models of the Universe with extra dimensions gravity propagates in the whole space-time. Graviton production by matter on the brane is significant in the early hot Universe. In a model of 3-brane with matter embedded in 5D space-time conditions for gravitons emitted from the brane to the bulk to return back to the brane are found. For a given 5-momentum of graviton falling back to the brane the interval between the times of emission and return to the brane is calculated. A method to calculate contribution to the energy-momentum tensor from multiple graviton bouncings is developed. Explicit expressions formore » contributions to the energy-momentum tensor of gravitons which have made one, two and three bounces are obtained and their magnitudes are numerically calculated. These expressions are used to solve the evolution equation for dark radiation. A relation connecting reheating temperature and the scale of extra dimension is obtained. For the reheating temperature T{sub R}∼ 10{sup 6} GeV we estimate the scale of extra dimension μ to be of order 10{sup −9} GeV (μ{sup −1}∼ 10{sup −5} cm)« less
Shape component analysis: structure-preserving dimension reduction on biological shape spaces.
Lee, Hao-Chih; Liao, Tao; Zhang, Yongjie Jessica; Yang, Ge
2016-03-01
Quantitative shape analysis is required by a wide range of biological studies across diverse scales, ranging from molecules to cells and organisms. In particular, high-throughput and systems-level studies of biological structures and functions have started to produce large volumes of complex high-dimensional shape data. Analysis and understanding of high-dimensional biological shape data require dimension-reduction techniques. We have developed a technique for non-linear dimension reduction of 2D and 3D biological shape representations on their Riemannian spaces. A key feature of this technique is that it preserves distances between different shapes in an embedded low-dimensional shape space. We demonstrate an application of this technique by combining it with non-linear mean-shift clustering on the Riemannian spaces for unsupervised clustering of shapes of cellular organelles and proteins. Source code and data for reproducing results of this article are freely available at https://github.com/ccdlcmu/shape_component_analysis_Matlab The implementation was made in MATLAB and supported on MS Windows, Linux and Mac OS. geyang@andrew.cmu.edu. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Higher (odd) dimensional quantum Hall effect and extended dimensional hierarchy
NASA Astrophysics Data System (ADS)
Hasebe, Kazuki
2017-07-01
We demonstrate dimensional ladder of higher dimensional quantum Hall effects by exploiting quantum Hall effects on arbitrary odd dimensional spheres. Non-relativistic and relativistic Landau models are analyzed on S 2 k - 1 in the SO (2 k - 1) monopole background. The total sub-band degeneracy of the odd dimensional lowest Landau level is shown to be equal to the winding number from the base-manifold S 2 k - 1 to the one-dimension higher SO (2 k) gauge group. Based on the chiral Hopf maps, we clarify the underlying quantum Nambu geometry for odd dimensional quantum Hall effect and the resulting quantum geometry is naturally embedded also in one-dimension higher quantum geometry. An origin of such dimensional ladder connecting even and odd dimensional quantum Hall effects is illuminated from a viewpoint of the spectral flow of Atiyah-Patodi-Singer index theorem in differential topology. We also present a BF topological field theory as an effective field theory in which membranes with different dimensions undergo non-trivial linking in odd dimensional space. Finally, an extended version of the dimensional hierarchy for higher dimensional quantum Hall liquids is proposed, and its relationship to quantum anomaly and D-brane physics is discussed.
Sustainable dimension adaptation measure in green township assessment criteria
NASA Astrophysics Data System (ADS)
Yaman, R.; Thadaniti, S.; Ahmad, N.; Halil, F. M.; Nasir, N. M.
2018-05-01
Urbanized areas are typically the most significant sources of environmental degradation, thus, an urban assessment criteria tools aiming at equally adapted sustainability dimensions need to be firmly embedded in benchmarking planning and design framework and upon occupancy. The need for integral systematic rating is recognized in order to evaluate the performance of sustainable neighborhood and to promote sustainable urban development. In this study, Green Building Index Township Assessment Criteria (GBI-TAC) will be measure on holistic sustainable dimension pillar (SDP) adaptation in order to assess and redefine the current sustainability assessment criteria for future sustainable neighborhood development (SND). The objective of the research is to find-out whether the current GBI-TAC and its variables fulfilled the holistic SDP adaptations towards sustainable neighborhood development in Malaysia. The stakeholder-inclusion approached is used in this research in order to gather professional’s stakeholders’ opinions regarding the SDP adaptations for sustainable neighborhood development. The data were analysed using IBM SPSS AMOS22 Structural Equation Modelling. The findings suggested an adaptation gap of SDP in current GBI-TAC even though all core-criteria supported SDP adaptation, hence lead to further review and refinement for future Neighborhood Assessment Criteria in Malaysia.
Information-theoretic measures of hydrogen-like ions in weakly coupled Debye plasmas
NASA Astrophysics Data System (ADS)
Zan, Li Rong; Jiao, Li Guang; Ma, Jia; Ho, Yew Kam
2017-12-01
Recent development of information theory provides researchers an alternative and useful tool to quantitatively investigate the variation of the electronic structure when atoms interact with the external environment. In this work, we make systematic studies on the information-theoretic measures for hydrogen-like ions immersed in weakly coupled plasmas modeled by Debye-Hückel potential. Shannon entropy, Fisher information, and Fisher-Shannon complexity in both position and momentum spaces are quantified in high accuracy for the hydrogen atom in a large number of stationary states. The plasma screening effect on embedded atoms can significantly affect the electronic density distributions, in both conjugate spaces, and it is quantified by the variation of information quantities. It is shown that the composite quantities (the Shannon entropy sum and the Fisher information product in combined spaces and Fisher-Shannon complexity in individual space) give a more comprehensive description of the atomic structure information than single ones. The nodes of wave functions play a significant role in the changes of composite information quantities caused by plasmas. With the continuously increasing screening strength, all composite quantities in circular states increase monotonously, while in higher-lying excited states where nodal structures exist, they first decrease to a minimum and then increase rapidly before the bound state approaches the continuum limit. The minimum represents the most reduction of uncertainty properties of the atom in plasmas. The lower bounds for the uncertainty product of the system based on composite information quantities are discussed. Our research presents a comprehensive survey in the investigation of information-theoretic measures for simple atoms embedded in Debye model plasmas.
Wang, Yue; Li, Xiangming; Tian, Hongmiao; Hu, Hong; Tian, Yu; Shao, Jinyou; Ding, Yucheng
2015-01-01
Dry adhesion observed in the feet of various small creatures has attracted considerable attention owing to the unique advantages such as self-cleaning, adaptability to rough surfaces along with repeatable and reversible adhesiveness. Among these advantages, for practical applications, proper detachability is critical for dry adhesives with artificial microstructures. In this study, we present a microstructured array consisting of both asymmetric rectangle-capped tip and tilted shafts, which produce an orthogonal anisotropy of the shearing strength along the long and short dimensions of the tip, with a maximum anti-shearing in the two directions along the longer dimension. Meanwhile, the tilt feature can enhance anisotropic shearing adhesion by increasing shearing strength in the forward shearing direction and decreasing strength in the reverse shearing direction along the short dimension of the tip, leading to a minimum anti-shearing in only one of the two directions along the shorter dimension of the rectangular tip. Such a microstructured adhesive with only one weak shearing direction, leading to well-controlled attachment and detachment of the adhesive, is created in our experiment by conventional double-sided exposure of a photoresist followed by a moulding process. PMID:25808338
Three Dimensional Transient Analysis of Microstrip Circuits in Multilayered Anisotropic Media
1991-11-14
dimensions, resonance is possible within the low gigahertz frequency range. Because the effects of diffraction during proximity-print x-ray lithography ...facilitate lead passage. The simulation results, comparing radi- paksgo and sourcl ation from a gasketed and ungasketed heatsink with an dMD TPI as... lithography are of critical importance, a number of previous researchers have attempted to calculate the diffraction patterns and minimum achievable
Many-body matter-wave dark soliton.
Delande, Dominique; Sacha, Krzysztof
2014-01-31
The Gross-Pitaevskii equation--which describes interacting bosons in the mean-field approximation--possesses solitonic solutions in dimension one. For repulsively interacting particles, the stationary soliton is dark, i.e., is represented by a local density minimum. Many-body effects may lead to filling of the dark soliton. Using quasiexact many-body simulations, we show that, in single realizations, the soliton appears totally dark although the single particle density tends to be uniform.
ERIC Educational Resources Information Center
Jayawardena, Lal
This presentation reviews the key dimensions of the environment problem and estimates the probable costs of arresting future environmental damage by expenditures to be undertaken in support of sustainable development during the decade of the 90s. It deals with the problem of pursuing a minimum "socially necessary" growth rate in the world economy…
European Scientific Notes. Volume 36, Number 4.
1982-03-30
de of gray cast iron, Mampaey demonstrated that Recherches Scientifiques et Techniques de the minimum riser dimensions needed to obtain I’lndustrie...through the nonprofit He is now making a similar study of ’nodular Industrial association Fabrimetal (Fdlration des cast iron. entreprises de I’industrie...SCIENTIFIC NOTES April 6. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(&) II. CONTRACT OR GRANT NUMBER(e) 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10
Numerical estimation of the relative entropy of entanglement
NASA Astrophysics Data System (ADS)
Zinchenko, Yuriy; Friedland, Shmuel; Gour, Gilad
2010-11-01
We propose a practical algorithm for the calculation of the relative entropy of entanglement (REE), defined as the minimum relative entropy between a state and the set of states with positive partial transpose. Our algorithm is based on a practical semidefinite cutting plane approach. In low dimensions the implementation of the algorithm in matlab provides an estimation for the REE with an absolute error smaller than 10-3.
Where are compact groups in the local Universe?
NASA Astrophysics Data System (ADS)
Díaz-Giménez, Eugenia; Zandivarez, Ariel
2015-06-01
Aims: The purpose of this work is to perform a statistical analysis of the location of compact groups in the Universe from observational and semi-analytical points of view. Methods: We used the velocity-filtered compact group sample extracted from the Two Micron All Sky Survey for our analysis. We also used a new sample of galaxy groups identified in the 2M++ galaxy redshift catalogue as tracers of the large-scale structure. We defined a procedure to search in redshift space for compact groups that can be considered embedded in other overdense systems and applied this criterion to several possible combinations of different compact and galaxy group subsamples. We also performed similar analyses for simulated compact and galaxy groups identified in a 2M++ mock galaxy catalogue constructed from the Millennium Run Simulation I plus a semi-analytical model of galaxy formation. Results: We observed that only ~27% of the compact groups can be considered to be embedded in larger overdense systems, that is, most of the compact groups are more likely to be isolated systems. The embedded compact groups show statistically smaller sizes and brighter surface brightnesses than non-embedded systems. No evidence was found that embedded compact groups are more likely to inhabit galaxy groups with a given virial mass or with a particular dynamical state. We found very similar results when the analysis was performed using mock compact and galaxy groups. Based on the semi-analytical studies, we predict that 70% of the embedded compact groups probably are 3D physically dense systems. Finally, real space information allowed us to reveal the bimodal behaviour of the distribution of 3D minimum distances between compact and galaxy groups. Conclusions: The location of compact groups should be carefully taken into account when comparing properties of galaxies in environments that are a priori different. Appendices are available in electronic form at http://www.aanda.orgFull Tables B.1 and B.2 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/578/A61
NASA Astrophysics Data System (ADS)
Singh, Akhilesh Kumar; Debnath, Tapas; Dey, Vidyut; Rai, Ram Naresh
2017-10-01
P-91 is modified 9Cr-1Mo steel. Fabricated structures and components of P-91 has a lot of application in power and chemical industry owing to its excellent properties like high temperature stress corrosion resistance, less susceptibility to thermal fatigue at high operating temperatures. The weld quality and surface finish of fabricated structure of P91 is very good when welded by Tungsten Inert Gas welding (TIG). However, the process has its limitation regarding weld penetration. The success of a welding process lies in fabricating with such a combination of parameters that gives maximum weld penetration and minimum weld width. To carry out an investigation on the effect of the autogenous TIG welding parameters on weld penetration and weld width, bead-on-plate welds were carried on P91 plates of thickness 6 mm in accordance to a Taguchi L9 design. Welding current, welding speed and gas flow rate were the three control variables in the investigation. After autogenous (TIG) welding, the dimension of the weld width, weld penetration and weld area were successfully measured by an image analysis technique developed for the study. The maximum error for the measured dimensions of the weld width, penetration and area with the developed image analysis technique was only 2 % compared to the measurements of Leica-Q-Win-V3 software installed in optical microscope. The measurements with the developed software, unlike the measurements under a microscope, required least human intervention. An Analysis of Variance (ANOVA) confirms the significance of the selected parameters. Thereafter, Taguchi's method was successfully used to trade-off between maximum penetration and minimum weld width while keeping the weld area at a minimum.
Detection of chaotic dynamics in human gait signals from mobile devices
NASA Astrophysics Data System (ADS)
DelMarco, Stephen; Deng, Yunbin
2017-05-01
The ubiquity of mobile devices offers the opportunity to exploit device-generated signal data for biometric identification, health monitoring, and activity recognition. In particular, mobile devices contain an Inertial Measurement Unit (IMU) that produces acceleration and rotational rate information from the IMU accelerometers and gyros. These signals reflect motion properties of the human carrier. It is well-known that the complexity of bio-dynamical systems gives rise to chaotic dynamics. Knowledge of chaotic properties of these systems has shown utility, for example, in detecting abnormal medical conditions and neurological disorders. Chaotic dynamics has been found, in the lab, in bio-dynamical systems data such as electrocardiogram (heart), electroencephalogram (brain), and gait data. In this paper, we investigate the following question: can we detect chaotic dynamics in human gait as measured by IMU acceleration and gyro data from mobile phones? To detect chaotic dynamics, we perform recurrence analysis on real gyro and accelerometer signal data obtained from mobile devices. We apply the delay coordinate embedding approach from Takens' theorem to reconstruct the phase space trajectory of the multi-dimensional gait dynamical system. We use mutual information properties of the signal to estimate the appropriate delay value, and the false nearest neighbor approach to determine the phase space embedding dimension. We use a correlation dimension-based approach together with estimation of the largest Lyapunov exponent to make the chaotic dynamics detection decision. We investigate the ability to detect chaotic dynamics for the different one-dimensional IMU signals, across human subject and walking modes, and as a function of different phone locations on the human carrier.
Hampson, Karen M; Cufflin, Matthew P; Mallen, Edward A H
2017-08-01
When fixating on a stationary object, the power of the eye's lens fluctuates. Studies have suggested that changes in these so-called microfluctuations in accommodation may be a factor in the onset and progression of short-sightedness. Like many physiological signals, the fluctuations in the power of the lens exhibit chaotic behaviour. A breakdown or reduction in chaos in physiological systems indicates stress to the system or pathology. The purpose of this study was to determine whether the chaos in fluctuations of the power of the lens changes with refractive error, i.e. how short-sighted a subject is, and/or accommodative demand, i.e. the effective distance of the object that is being viewed. Six emmetropes (EMMs, non-short-sighted), six early-onset myopes (EOMs, onset of short-sightedness before the age of 15), and six late-onset myopes (LOMs, onset of short-sightedness after the age of 15) took part in the study. Accommodative microfluctuations were measured at 22 Hz using an SRW-5000 autorefractor at accommodative demands of 1 D (dioptres), 2 D, and 3 D. Chaos theory analysis was used to determine the embedding lag, embedding dimension, limit of predictability, and Lyapunov exponent. Topological transitivity was also tested for. For comparison, the power spectrum and standard deviation were calculated for each time record. The EMMs had a statistically significant higher Lyapunov exponent than the LOMs ([Formula: see text] vs. [Formula: see text]) and a lower embedding dimension than the LOMs ([Formula: see text] vs. [Formula: see text]). There was insufficient evidence (non-significant p value) of a difference between EOMs and EMMs or EOMs and LOMs. The majority of time records were topologically transitive. There was insufficient evidence of accommodative demand having an effect. Power spectrum analysis and assessment of the standard deviation of the fluctuations failed to discern differences based on refractive error. Chaos differences in accommodation microfluctuations indicate that the control system for LOMs is under stress in comparison to EMMs. Chaos theory analysis is a more sensitive marker of changes in accommodation microfluctuations than traditional analysis methods.
Fermion localization on a split brane
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chumbes, A. E. R.; Vasquez, A. E. O.; Hott, M. B.
2011-05-15
In this work we analyze the localization of fermions on a brane embedded in five-dimensional, warped and nonwarped, space-time. In both cases we use the same nonlinear theoretical model with a nonpolynomial potential featuring a self-interacting scalar field whose minimum energy solution is a soliton (a kink) which can be continuously deformed into a two-kink. Thus a single brane splits into two branes. The behavior of spin 1/2 fermions wave functions on the split brane depends on the coupling of fermions to the scalar field and on the geometry of the space-time.
Design of MSR primary circuit with minimum pressure losses
NASA Astrophysics Data System (ADS)
Noga, Tomáš; Žitek, Pavel; Valenta, Václav
This article describes a design of a MSR primary circuit with minimum pressure losses. It includes a brief description of this type of a reactor and its integral layout, properties, purpose, etc. The objective of this paper is to define problems of pressure losses calculation and to design a proper device for a primary circuit of MSR reactor, including its basic dimensions. Thanks to this, it can become an initial project for a construction of a real piece of work. This is the main contribution of the carried out study. Of course, this article is not a detailed solution, but it points out facts and problems, which future designers may have to face. The further step of our work will be a reconstruction of the current experiment for a two-stage flowing.
Anchorage Behaviors of Frictional Tieback Anchors in Silty Sand
NASA Astrophysics Data System (ADS)
Hsu, Shih-Tsung; Hsiao, Wen-Ta; Chen, Ke-Ting; Hu, Wen-Chi; Wu, Ssu-Yi
2017-06-01
Soil anchors are extensively used in geotechnical applications, most commonly serve as tieback walls in deep excavations. To investigate the anchorage mechanisms of this tieback anchor, a constitutive model that considers both strain hardening and softening and volume dilatancy entitled SHASOVOD model, and FLAC3D software are used to perform 3-D numerical analyses. The results from field anchor tests are compared with those calculated by numerical analyses to enhance the applicability of the numerical method. After the calibration, this research carried out the parameter studies by numerical analyses. The numerical results reveal that whether the yield of soil around an anchor develops to ground surface and/or touches the diaphragm wall depending on the overburden depth H and the embedded depth Z of an anchor, this study suggests the minimum overburden and embedded depths to avoid the yield of soils develop to ground surface and/or touch the diaphragm wall. When the embedded depth, overburden depth or fixed length of an anchor increases, the anchorage capacity also increases. Increasing fixed length should be the optimum method to increase the anchorage capacity for fixed length less than 20m. However, when the fixed length of an anchor exceeds 30 m, the increasing rate of anchorage capacity per fixed length decreases, and progressive yield occurs obviously between the fixed length and surrounding soil.
Dynamic Reconfiguration of a RGBD Sensor Based on QoS and QoC Requirements in Distributed Systems.
Munera, Eduardo; Poza-Lujan, Jose-Luis; Posadas-Yagüe, Juan-Luis; Simó-Ten, José-Enrique; Noguera, Juan Fco Blanes
2015-07-24
The inclusion of embedded sensors into a networked system provides useful information for many applications. A Distributed Control System (DCS) is one of the clearest examples where processing and communications are constrained by the client's requirements and the capacity of the system. An embedded sensor with advanced processing and communications capabilities supplies high level information, abstracting from the data acquisition process and objects recognition mechanisms. The implementation of an embedded sensor/actuator as a Smart Resource permits clients to access sensor information through distributed network services. Smart resources can offer sensor services as well as computing, communications and peripheral access by implementing a self-aware based adaptation mechanism which adapts the execution profile to the context. On the other hand, information integrity must be ensured when computing processes are dynamically adapted. Therefore, the processing must be adapted to perform tasks in a certain lapse of time but always ensuring a minimum process quality. In the same way, communications must try to reduce the data traffic without excluding relevant information. The main objective of the paper is to present a dynamic configuration mechanism to adapt the sensor processing and communication to the client's requirements in the DCS. This paper describes an implementation of a smart resource based on a Red, Green, Blue, and Depth (RGBD) sensor in order to test the dynamic configuration mechanism presented.
Photosensitizer-Embedded Polyacrylonitrile Nanofibers as Antimicrobial Non-Woven Textile
Stanley, Sarah L.; Scholle, Frank; Zhu, Jiadeng; Lu, Yao; Zhang, Xiangwu; Situ, Xingci; Ghiladi, Reza A.
2016-01-01
Toward the objective of developing platform technologies for anti-infective materials based upon photodynamic inactivation, we employed electrospinning to prepare a non-woven textile comprised of polyacrylonitrile nanofibers embedded with a porphyrin-based cationic photosensitizer; termed PAN-Por(+). Photosensitizer loading was determined to be 34.8 nmol/mg material; with thermostability to 300 °C. Antibacterial efficacy was evaluated against four bacteria belonging to the ESKAPE family of pathogens (Staphylococcus aureus; vancomycin-resistant Enterococcus faecium; Acinetobacter baumannii; and Klebsiella pneumonia), as well as Escherichia coli. Our results demonstrated broad photodynamic inactivation of all bacterial strains studied upon illumination (30 min; 65 ± 5 mW/cm2; 400–700 nm) by a minimum of 99.9996+% (5.8 log units) regardless of taxonomic classification. PAN-Por(+) also inactivated human adenovirus-5 (~99.8% reduction in PFU/mL) and vesicular stomatitis virus (>7 log units reduction in PFU/mL). When compared to cellulose-based materials employing this same photosensitizer; the higher levels of photodynamic inactivation achieved here with PAN-Por(+) are likely due to the combined effects of higher photosensitizer loading and a greater surface area imparted by the use of nanofibers. These results demonstrate the potential of photosensitizer-embedded polyacrylonitrile nanofibers to serve as scalable scaffolds for anti-infective or self-sterilizing materials against both bacteria and viruses when employing a photodynamic inactivation mode of action. PMID:28335205
Analysis of Fractional Flow for Transient Two-Phase Flow in Fractal Porous Medium
NASA Astrophysics Data System (ADS)
Lu, Ting; Duan, Yonggang; Fang, Quantang; Dai, Xiaolu; Wu, Jinsui
2016-03-01
Prediction of fractional flow in fractal porous medium is important for reservoir engineering and chemical engineering as well as hydrology. A physical conceptual fractional flow model of transient two-phase flow is developed in fractal porous medium based on the fractal characteristics of pore-size distribution and on the approximation that porous medium consist of a bundle of tortuous capillaries. The analytical expression for fractional flow for wetting phase is presented, and the proposed expression is the function of structural parameters (such as tortuosity fractal dimension, pore fractal dimension, maximum and minimum diameters of capillaries) and fluid properties (such as contact angle, viscosity and interfacial tension) in fractal porous medium. The sensitive parameters that influence fractional flow and its derivative are formulated, and their impacts on fractional flow are discussed.
An opening criterion for dust gaps in protoplanetary discs
NASA Astrophysics Data System (ADS)
Dipierro, Giovanni; Laibe, Guillaume
2017-08-01
We aim to understand under which conditions a low-mass planet can open a gap in viscous dusty protoplanetary discs. For this purpose, we extend the theory of dust radial drift to include the contribution from the tides of an embedded planet and from the gas viscous forces. From this formalism, we derive (I) a grain-size-dependent criterion for dust gap opening in discs, (II) an estimate of the location of the outer edge of the dust gap and (III) an estimate of the minimum Stokes number above which low-mass planets are able to carve gaps that appear only in the dust disc. These analytical estimates are particularly helpful to appraise the minimum mass of a hypothetical planet carving gaps in discs observed at long wavelengths and high resolution. We validate the theory against 3D smoothed particle hydrodynamics simulations of planet-disc interaction in a broad range of dusty protoplanetary discs. We find a remarkable agreement between the theoretical model and the numerical experiments.
An approximate spin design criterion for monoplanes, 1 May 1939
NASA Technical Reports Server (NTRS)
Seidman, O.; Donlan, C. J.
1976-01-01
An approximate empirical criterion, based on the projected side area and the mass distribution of the airplane, was formulated. The British results were analyzed and applied to American designs. A simpler design criterion, based solely on the type and the dimensions of the tail, was developed; it is useful in a rapid estimation of whether a new design is likely to comply with the minimum requirements for safety in spinning.
Paschoal, Sérgio Márcio Pacheco; Filho, Wilson Jacob; Litvoc, Júlio
2008-01-01
OBJECTIVE To describe item reduction and its distribution into dimensions in the construction process of a quality of life evaluation instrument for the elderly. METHODS The sampling method was chosen by convenience through quotas, with selection of elderly subjects from four programs to achieve heterogeneity in the “health status”, “functional capacity”, “gender”, and “age” variables. The Clinical Impact Method was used, consisting of the spontaneous and elicited selection by the respondents of relevant items to the construct Quality of Life in Old Age from a previously elaborated item pool. The respondents rated each item’s importance using a 5-point Likert scale. The product of the proportion of elderly selecting the item as relevant (frequency) and the mean importance score they attributed to it (importance) represented the overall impact of that item in their quality of life (impact). The items were ordered according to their impact scores and the top 46 scoring items were grouped in dimensions by three experts. A review of the negative items was performed. RESULTS One hundred and ninety three people (122 women and 71 men) were interviewed. Experts distributed the 46 items into eight dimensions. Closely related items were grouped and dimensions not reaching the minimum expected number of items received additional items resulting in eight dimensions and 43 items. DISCUSSION The sample was heterogeneous and similar to what was expected. The dimensions and items demonstrated the multidimensionality of the construct. The Clinical Impact Method was appropriate to construct the instrument, which was named Elderly Quality of Life Index - EQoLI. An accuracy process will be examined in the future. PMID:18438571
Kozlovsky, Yonathan; Zimmerberg, Joshua; Kozlov, Michael M.
2004-01-01
We consider the elastic behavior of flat lipid monolayer embedding cylindrical inclusions oriented obliquely with respect to the monolayer plane. An oblique inclusion models a fusion peptide, a part of a specialized protein capable of inducing merger of biological membranes in the course of fundamental cellular processes. Although the crucial importance of the fusion peptides for membrane merger is well established, the molecular mechanism of their action remains unknown. This analysis is aimed at revealing mechanical deformations and stresses of lipid monolayers induced by the fusion peptides, which, potentially, can destabilize the monolayer structure and enhance membrane fusion. We calculate the deformation of a monolayer embedding a single oblique inclusion and subject to a lateral tension. We analyze the membrane-mediated interactions between two inclusions, taking into account bending of the monolayer and tilt of the hydrocarbon chains with respect to the surface normal. In contrast to a straightforward prediction that the oblique inclusions should induce tilt of the lipid chains, our analysis shows that the monolayer accommodates the oblique inclusion solely by bending. We find that the interaction between two inclusions varies nonmonotonically with the interinclusion distance and decays at large separations as square of the distance, similar to the electrostatic interaction between two electric dipoles in two dimensions. This long-range interaction is predicted to dominate the other interactions previously considered in the literature. PMID:15298906
New Views on Dark Matter from Emergent Gravity
NASA Astrophysics Data System (ADS)
Sun, Sichun; Zhang, Yun-Long
2018-01-01
We discuss a scenario that apparent dark matter comes from the induced gravity in the (3+1)- dimensional spacetime, which can be embedded into one higher dimensional flat spacetime. The stress tensor of dark energy and dark matter is identified with the Brown-York stress tensor on the hypersurface, and we find an interesting constraint relation between the dark matter and dark energy density parameter and baryonic density parameter. Our approach may show a new understanding for Verlinde's emergent gravity from higher dimensions. We also comment on some phenomenological implications, including gravitational wave solutions and MOND limit.
Ground state structure of random magnets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bastea, S.; Duxbury, P.M.
1998-10-01
Using exact optimization methods, we find all of the ground states of ({plus_minus}h) random-field Ising magnets (RFIM) and of dilute antiferromagnets in a field (DAFF). The degenerate ground states are usually composed of isolated clusters (two-level systems) embedded in a frozen background. We calculate the paramagnetic response (sublattice response) and the ground state entropy for the RFIM (DAFF) due to these clusters. In both two and three dimensions there is a broad regime in which these quantities are strictly positive, even at irrational values of h/J (J is the exchange constant). {copyright} {ital 1998} {ital The American Physical Society}
Troubé, Sarah
2016-12-01
The paper considers the philosophy of psychiatry from the perspective of everyday life, as a particular structure of experience. We outline some questions raised by disturbances typical of psychotic disorders with regard to a phenomenology of the everyday and common sense. As a link between philosophy and clinical psychopathology, this phenomenology implies a transcendental point of view, embedded in concrete and practical forms of ordinary experience, along with social norms. This opens the possibility of a mutual questioning between philosophy and psychiatry, drawing on its clinical, epistemological, and ethical dimensions.
NASA Technical Reports Server (NTRS)
Bisagni, Chiara; Vescovini, Riccardo; Davila, Carlos G.
2010-01-01
A procedure is proposed for the assessment of the damage tolerance and collapse of stiffened composite panels using a single-stringer compression specimen. The dimensions of the specimen are determined such that the specimen s nonlinear response and collapse are representative of an equivalent multi-stringer panel in compression. Experimental tests are conducted on specimens with and without an embedded delamination. A shell-based finite element model with intralaminar and interlaminar damage capabilities is developed to predict the postbuckling response as well as the damage evolution from initiation to collapse.
Arcmancer: Geodesics and polarized radiative transfer library
NASA Astrophysics Data System (ADS)
Pihajoki, Pauli; Mannerkoski, Matias; Nättilä, Joonas; Johansson, Peter H.
2018-05-01
Arcmancer computes geodesics and performs polarized radiative transfer in user-specified spacetimes. The library supports Riemannian and semi-Riemannian spaces of any dimension and metric; it also supports multiple simultaneous coordinate charts, embedded geometric shapes, local coordinate systems, and automatic parallel propagation. Arcmancer can be used to solve various problems in numerical geometry, such as solving the curve equation of motion using adaptive integration with configurable tolerances and differential equations along precomputed curves. It also provides support for curves with an arbitrary acceleration term and generic tools for generating ray initial conditions and performing parallel computation over the image, among other tools.
Testing for nonlinear dependence in financial markets.
Dore, Mohammed; Matilla-Garcia, Mariano; Marin, Manuel Ruiz
2011-07-01
This article addresses the question of improving the detection of nonlinear dependence by means of recently developed nonparametric tests. To this end a generalized version of BDS test and a new test based on symbolic dynamics are used on realizations from a well-known artificial market for which the dynamic equation governing the market is known. Comparisons with other tests for detecting nonlinearity are also provided. We show that the test based on symbolic dynamics outperforms other tests with the advantage that it depends only on one free parameter, namely the embedding dimension. This does not hold for other tests for nonlinearity.
Embedding a pedagogical model in the design of an online course.
Sternberger, Carol S
2002-01-01
The importance of course design and its relationship to learning is overlooked when the electronic version of a course is static. The author discusses the process used to redesign a traditional course into a dynamic and interactive Web-based course by using a pedagogical model developed specifically for hypermedia. Congruence between the instructional methods and the media is a must for a successful design that meets the needs of a wide variety of learners. The hyperlearning model, Dimensions, provides the infrastructure to facilitate the congruence of methods and media while supporting multiple learning styles.
Relation of the fractal structure of organic pigments to their performance
NASA Astrophysics Data System (ADS)
Skillas, G.; Agashe, N.; Kohls, D. J.; Ilavsky, J.; Jemian, P.; Clapp, L.; Schwartz, R. J.; Beaucage, G.
2002-05-01
Different pigments embedded in polymer matrices were examined by small angle scattering of x- rays over 3 wave number decades. The scattering intensities show differences both in the mass fractal dimension (varying between 1.4 and 2.67) and the size of the particles. The differences are pronounced between dry pigment powders and the same powders in a polymer matrix as well as between the pigments themselves. Further, a correlation of pigment geometrical configuration and pigment performance, as perceived by the human eye, shows how pigments with a maximum color brightness per pigment mass can be created.
Geometry of quantum dynamics in infinite-dimensional Hilbert space
NASA Astrophysics Data System (ADS)
Grabowski, Janusz; Kuś, Marek; Marmo, Giuseppe; Shulman, Tatiana
2018-04-01
We develop a geometric approach to quantum mechanics based on the concept of the Tulczyjew triple. Our approach is genuinely infinite-dimensional, i.e. we do not restrict considerations to finite-dimensional Hilbert spaces, contrary to many other works on the geometry of quantum mechanics, and include a Lagrangian formalism in which self-adjoint (Schrödinger) operators are obtained as Lagrangian submanifolds associated with the Lagrangian. As a byproduct we also obtain results concerning coadjoint orbits of the unitary group in infinite dimensions, embedding of pure states in the unitary group, and self-adjoint extensions of symmetric relations.
Keil, Nina M; Pommereau, Marc; Patt, Antonia; Wechsler, Beat; Gygax, Lorenz
2017-02-01
Confined goats spend a substantial part of the day feeding. A poorly designed feeding place increases the risk of feeding in nonphysiological body postures, and even injury. Scientifically validated information on suitable dimensions of feeding places for loose-housed goats is almost absent from the literature. The aim of the present study was, therefore, to determine feeding place dimensions that would allow goats to feed in a species-appropriate, relaxed body posture. A total of 27 goats with a height at the withers of 62 to 80 cm were included in the study. Goats were tested individually in an experimental feeding stall that allowed the height difference between the feed table, the standing area of the forelegs, and a feeding area step (difference in height between forelegs and hind legs) to be varied. The goats accessed the feed table via a palisade feeding barrier. The feed table was equipped with recesses at varying distances to the feeding barrier (5-55 cm in 5-cm steps) at angles of 30°, 60°, 90°, 120°, or 150° (feeding angle), which were filled with the goats' preferred food. In 18 trials, balanced for order across animals, each animal underwent all possible combinations of feeding area step (3 levels: 0, 10, and 20 cm) and of difference in height between feed table and standing area of forelegs (6 levels: 0, 5, 10, 15, 20, and 25 cm). The minimum and maximum reach at which the animals could reach feed on the table with a relaxed body posture was determined for each combination. Statistical analysis was performed using mixed-effects models. The animals were able to feed with a relaxed posture when the feed table was at least 10 cm higher than the standing height of the goats' forelegs. Larger goats achieved smaller minimum reaches and minimum reach increased if the goats' head and neck were angled. Maximum reach increased with increasing height at withers and height of the feed table. The presence of a feeding area step had no influence on minimum and maximum reach. Based on these results, the goats' feeding place can be designed to ensure that the animals are able to reach all of the feed in the manger or on the feed table with a relaxed posture, thus avoiding injuries and nonphysiological stress on joints and hooves. A feeding area step up to a maximum of 20 cm need not be taken into account in terms of feeding reach. However, the feed table must be raised at least 10 cm above the standing area to allow the goats to feed in a species-appropriate, relaxed posture. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
A review of interdependence of sustainable building
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ju, Chuanjing; Ning, Yan, E-mail: cqningyan@gmail.com; Pan, Wei
2016-01-15
ABSTRACT: Despite the worldwide promotion of the sustainable building (SB) approach, its associated interdependence has seldom been explored. This knowledge gap is significant given the paradigm shift of regarding SBs as complex socio-technical systems embedded with multifaceted interdependence. The aim of this paper is to examine the interdependence of SB through a literature review. The literature review was guided by a framework comprising three dimensions of SB systems, i.e., building performance, methodology and stakeholders, on their theoretical grounds ranged from reductionism to holism. In order to articulate the integration of the three dimensions, this paper examined zero carbon building asmore » a specific case of SB. The findings contribute an innovative approach to examining the interdependence of SB, and should guide the development of strategies for managing the trade-offs in delivering SBs. - Highlights: • Performance scope of sustainable building triggers interdependence. • Material flow from cradle to cradle causes interdependence. • Interdependence occurs between the building and their context. • Interdependence exists in stakeholders' participation.« less
Analyzing a stochastic time series obeying a second-order differential equation.
Lehle, B; Peinke, J
2015-06-01
The stochastic properties of a Langevin-type Markov process can be extracted from a given time series by a Markov analysis. Also processes that obey a stochastically forced second-order differential equation can be analyzed this way by employing a particular embedding approach: To obtain a Markovian process in 2N dimensions from a non-Markovian signal in N dimensions, the system is described in a phase space that is extended by the temporal derivative of the signal. For a discrete time series, however, this derivative can only be calculated by a differencing scheme, which introduces an error. If the effects of this error are not accounted for, this leads to systematic errors in the estimation of the drift and diffusion functions of the process. In this paper we will analyze these errors and we will propose an approach that correctly accounts for them. This approach allows an accurate parameter estimation and, additionally, is able to cope with weak measurement noise, which may be superimposed to a given time series.
LEE, YEON-SHIM; KAPLAN, CELIA P.; PEREZ-STABLE, ELISEO J.
2014-01-01
The purpose of this study was to identify dimensions of elder mistreatment in Chinese and Korean immigrant communities and to increase sociocultural understanding of such mistreatment by elucidating the complexities of abuse embedded in unique social and cultural contexts. In-depth interviews were conducted with 20 local professionals working primarily in Asian elderly advocacy, and six focus group discussions were conducted involving 60 community members in the San Francisco Bay area. Five dimensions of elder mistreatment were identified: psychological abuse, neglect by a trusted person, financial exploitation, physical abuse, and sexual abuse. In general, fewer Korean community member participants reported having observed physical or financial abuse than Chinese groups, but they reported greater knowledge of situations involving psychological abuse, neglect by a trusted person, and sexual abuse. The contexts of cultural influences and immigration and acculturation were salient themes that shaped participants’ subjective perceptions and beliefs about elder abuse and hence help-seeking behaviors. PMID:24779539
Lee, Yeon-Shim; Kaplan, Celia P.; Perez-Stable, Eliseo J.
2014-01-01
The purpose of this study was to identify dimensions of elder mistreatment in Chinese and Korean immigrant communities and to increase sociocultural understanding of such mistreatment by elucidating the complexities of abuse embedded in unique social and cultural contexts. In-depth interviews were conducted with 20 local professionals working primarily in Asian elderly advocacy, and six focus group discussions were conducted involving 60 community members in the San Francisco Bay area. Five dimensions of elder mistreatment were identified: psychological abuse, neglect by a trusted person, financial exploitation, physical abuse, and sexual abuse. In general, fewer Korean community member participants reported having observed physical or financial abuse than Chinese groups, but they reported greater knowledge of situations involving psychological abuse, neglect by a trusted person, and sexual abuse. The contexts of cultural influences and immigration and acculturation were salient themes that shaped participants’ subjective perceptions and beliefs about elder abuse and hence help-seeking behaviors. PMID:25431530
Callanan, Maureen; Cervantes, Christi; Loomis, Molly
2011-11-01
We consider research and theory relevant to the notion of informal learning. Beginning with historical and definitional issues, we argue that learning happens not just in schools or in school-aged children. Many theorists have contrasted informal learning with formal learning. Moving beyond this dichotomy, and away from a focus on where learning occurs, we discuss five dimensions of informal learning that are drawn from the literature: (1) non-didactive, (2) highly socially collaborative, (3) embedded in meaningful activity, (4) initiated by learner's interest or choice, and (5) removed from external assessment. We consider these dimensions in the context of four sample domains: learning a first language, learning about the mind and emotions within families and communities, learning about science in family conversations and museum settings, and workplace learning. Finally, we conclude by considering convergences and divergences across the different literatures and suggesting areas for future research. WIREs Cogni Sci 2011 2 646-655 DOI: 10.1002/wcs.143 For further resources related to this article, please visit the WIREs website. Copyright © 2011 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Pomarède, Daniel; Hoffman, Yehuda; Courtois, Hélène M.; Tully, R. Brent
2017-08-01
The network of filaments with embedded clusters surrounding voids, which has been seen in maps derived from redshift surveys and reproduced in simulations, has been referred to as the cosmic web. A complementary description is provided by considering the shear in the velocity field of galaxies. The eigenvalues of the shear provide information regarding whether or not a region is collapsing in three dimensions, which is the condition for a knot, expanding in three dimensions, which is the condition for a void, or in the intermediate condition of a filament or sheet. The structures that are quantitatively defined by the eigenvalues can be approximated by iso-contours that provide a visual representation of the cosmic velocity (V) web. The current application is based on radial peculiar velocities from the Cosmicflows-2 collection of distances. The three-dimensional velocity field is constructed using the Wiener filter methodology in the linear approximation. Eigenvalues of the velocity shear are calculated at each point on a grid. Here, knots and filaments are visualized across a local domain of diameter ˜ 0.1c.
Superstring Compactification and Low Energy Phenomenology.
NASA Astrophysics Data System (ADS)
Mohapatra, Pramoda Kumar
We have presented some aspects of Superstring compactification from 10 to 4 dimensions and the effect of different types of compactification of the extra 6 dimensions on the low energy physics. We have reviewed the consequences of demanding the extra 6 dimensions to form a manifold as well as an N = 1 Supersymmetry at low energies. While doing this we have also highlighted some of the fundamental phenomenological problems like proton decay and neutrino mass and their possible solutions. The dissertation includes a description of the method of calculation of discrete symmetries and Yukawa couplings between different fermions and mirror fermions in these kinds of manifold compactification. The explicit calculations for one particular case with three fermion generations is presented. The reasons for the necessity of an intermediate scale of symmetry breaking (between Plank scale and the electro-weak scale) are explained and one particular scenerio of such symmetry breaking which preserves Supersymmetry is given. We have studied the effect of E _6 singlets on F-flatness and on the phenomenology. We have also reviewed the idea of compactification in a completely different way, i.e. not on a regular manifold but on a manifold with singularities called an orbifold. We have shown that with the so-called standard embedding, meaning identifying the gauge connection with the spin connection, needed for anomaly cancellation and modular invariance, only one model has a chance of being phenomenologically realistic. We have provided explicit tables of all the relevant quantum numbers of the fermions in the fundamental representation of the gauge group E _6 and showed that there are three possible ways of embedding electric charge in the generators of E _6. We have given the explicit form of the renormalization group equation for sin^2theta_{ rm W} and alpha_ {s} for the most usual chain of breaking E _6 down to SU(3)_ {c}otimes SU(2)_{L}otimes(1) _{Y}. The importance of the evolution of the coupling constant on the compactification is also stressed. We have analysed the successes and the limitations of Superstring theories and have mentioned the new frontiers in compactification.
Doctor, Teacher, and Stethoscope: Neural Representation of Different Types of Semantic Relations.
Xu, Yangwen; Wang, Xiaosha; Wang, Xiaoying; Men, Weiwei; Gao, Jia-Hong; Bi, Yanchao
2018-03-28
Concepts can be related in many ways. They can belong to the same taxonomic category (e.g., "doctor" and "teacher," both in the category of people) or be associated with the same event context (e.g., "doctor" and "stethoscope," both associated with medical scenarios). How are these two major types of semantic relations coded in the brain? We constructed stimuli from three taxonomic categories (people, manmade objects, and locations) and three thematic categories (school, medicine, and sports) and investigated the neural representations of these two dimensions using representational similarity analyses in human participants (10 men and nine women). In specific regions of interest, the left anterior temporal lobe (ATL) and the left temporoparietal junction (TPJ), we found that, whereas both areas had significant effects of taxonomic information, the taxonomic relations had stronger effects in the ATL than in the TPJ ("doctor" and "teacher" closer in ATL neural activity), with the reverse being true for thematic relations ("doctor" and "stethoscope" closer in TPJ neural activity). A whole-brain searchlight analysis revealed that widely distributed regions, mainly in the left hemisphere, represented the taxonomic dimension. Interestingly, the significant effects of the thematic relations were only observed after the taxonomic differences were controlled for in the left TPJ, the right superior lateral occipital cortex, and other frontal, temporal, and parietal regions. In summary, taxonomic grouping is a primary organizational dimension across distributed brain regions, with thematic grouping further embedded within such taxonomic structures. SIGNIFICANCE STATEMENT How are concepts organized in the brain? It is well established that concepts belonging to the same taxonomic categories (e.g., "doctor" and "teacher") share neural representations in specific brain regions. How concepts are associated in other manners (e.g., "doctor" and "stethoscope," which are thematically related) remains poorly understood. We used representational similarity analyses to unravel the neural representations of these different types of semantic relations by testing the same set of words that could be differently grouped by taxonomic categories or by thematic categories. We found that widely distributed brain areas primarily represented taxonomic categories, with the thematic categories further embedded within the taxonomic structure. Copyright © 2018 the authors 0270-6474/18/383303-15$15.00/0.
The complexity of translationally invariant low-dimensional spin lattices in 3D
NASA Astrophysics Data System (ADS)
Bausch, Johannes; Piddock, Stephen
2017-11-01
In this theoretical paper, we consider spin systems in three spatial dimensions and consider the computational complexity of estimating the ground state energy, known as the local Hamiltonian problem, for translationally invariant Hamiltonians. We prove that the local Hamiltonian problem for 3D lattices with face-centered cubic unit cells and 4-local translationally invariant interactions between spin-3/2 particles and open boundary conditions is QMAEXP-complete, where QMAEXP is the class of problems which can be verified in exponential time on a quantum computer. We go beyond a mere embedding of past hard 1D history state constructions, for which the local spin dimension is enormous: even state-of-the-art constructions have local dimension 42. We avoid such a large local dimension by combining some different techniques in a novel way. For the verifier circuit which we embed into the ground space of the local Hamiltonian, we utilize a recently developed computational model, called a quantum ring machine, which is especially well suited for translationally invariant history state constructions. This is encoded with a new and particularly simple universal gate set, which consists of a single 2-qubit gate applied only to nearest-neighbour qubits. The Hamiltonian construction involves a classical Wang tiling problem as a binary counter which translates one cube side length into a binary description for the encoded verifier input and a carefully engineered history state construction that implements the ring machine on the cubic lattice faces. These novel techniques allow us to significantly lower the local spin dimension, surpassing the best translationally invariant result to date by two orders of magnitude (in the number of degrees of freedom per coupling). This brings our models on par with the best non-translationally invariant construction.
Patterns of Twitter Behavior Among Networks of Cannabis Dispensaries in California
Chew, Robert F; Hsieh, Yuli P; Bieler, Gayle S; Bobashev, Georgiy V; Siege, Christopher; Zarkin, Gary A
2017-01-01
Background Twitter represents a social media platform through which medical cannabis dispensaries can rapidly promote and advertise a multitude of retail products. Yet, to date, no studies have systematically evaluated Twitter behavior among dispensaries and how these behaviors influence the formation of social networks. Objectives This study sought to characterize common cyberbehaviors and shared follower networks among dispensaries operating in two large cannabis markets in California. Methods From a targeted sample of 119 dispensaries in the San Francisco Bay Area and Greater Los Angeles, we collected metadata from the dispensary accounts using the Twitter API. For each city, we characterized the network structure of dispensaries based upon shared followers, then empirically derived communities with the Louvain modularity algorithm. Principal components factor analysis was employed to reduce 12 Twitter measures into a more parsimonious set of cyberbehavioral dimensions. Finally, quadratic discriminant analysis was implemented to verify the ability of the extracted dimensions to classify dispensaries into their derived communities. Results The modularity algorithm yielded three communities in each city with distinct network structures. The principal components factor analysis reduced the 12 cyberbehaviors into five dimensions that encompassed account age, posting frequency, referencing, hyperlinks, and user engagement among the dispensary accounts. In the quadratic discriminant analysis, the dimensions correctly classified 75% (46/61) of the communities in the San Francisco Bay Area and 71% (41/58) in Greater Los Angeles. Conclusions The most centralized and strongly connected dispensaries in both cities had newer accounts, higher daily activity, more frequent user engagement, and increased usage of embedded media, keywords, and hyperlinks. Measures derived from both network structure and cyberbehavioral dimensions can serve as key contextual indicators for the online surveillance of cannabis dispensaries and consumer markets over time. PMID:28676471
Minimum weight design of rectangular and tapered helicopter rotor blades with frequency constraints
NASA Technical Reports Server (NTRS)
Chattopadhyay, Aditi; Walsh, Joanne L.
1988-01-01
The minimum weight design of a helicopter rotor blade subject to constraints on coupled flap-lag natural frequencies has been studied. A constraint has also been imposed on the minimum value of the autorotational inertia of the blade in order to ensure that it has sufficient inertia to autorotate in the case of engine failure. The program CAMRAD is used for the blade modal analysis and CONMIN is used for the optimization. In addition, a linear approximation analysis involving Taylor series expansion has been used to reduce the analysis effort. The procedure contains a sensitivity analysis which consists of analytical derivatives of the objective function and the autorotational inertia constraint and central finite difference derivatives of the frequency constraints. Optimum designs have been obtained for both rectangular and tapered blades. Design variables include taper ratio, segment weights, and box beam dimensions. It is shown that even when starting with an acceptable baseline design, a significant amount of weight reduction is possible while satisfying all the constraints for both rectangular and tapered blades.
Minimum weight design of rectangular and tapered helicopter rotor blades with frequency constraints
NASA Technical Reports Server (NTRS)
Chattopadhyay, Aditi; Walsh, Joanne L.
1988-01-01
The minimum weight design of a helicopter rotor blade subject to constraints on coupled flap-lag natural frequencies has been studied. A constraint has also been imposed on the minimum value of the autorotational inertia of the blade in order to ensure that it has sufficient inertia to aurorotate in the case of engine failure. The program CAMRAD is used for the blade modal analysis and CONMIN is used for the optimization. In addition, a linear approximation analysis involving Taylor series expansion has been used to reduce the analysis effort. The procedure contains a sensitivity analysis which consists of analytical derivatives of the objective function and the autorotational inertia constraint and central finite difference derivatives of the frequency constraints. Optimum designs have been obtained for both rectangular and tapered blades. Design variables include taper ratio, segment weights, and box beam dimensions. It is shown that even when starting with an acceptable baseline design, a significant amount of weight reduction is possible while satisfying all the constraints for both rectangular and tapered blades.
Minimum weight design of helicopter rotor blades with frequency constraints
NASA Technical Reports Server (NTRS)
Chattopadhyay, Aditi; Walsh, Joanne L.
1989-01-01
The minimum weight design of helicopter rotor blades subject to constraints on fundamental coupled flap-lag natural frequencies has been studied in this paper. A constraint has also been imposed on the minimum value of the blade autorotational inertia to ensure that the blade has sufficient inertia to autorotate in case of an engine failure. The program CAMRAD has been used for the blade modal analysis and the program CONMIN has been used for the optimization. In addition, a linear approximation analysis involving Taylor series expansion has been used to reduce the analysis effort. The procedure contains a sensitivity analysis which consists of analytical derivatives of the objective function and the autorotational inertia constraint and central finite difference derivatives of the frequency constraints. Optimum designs have been obtained for blades in vacuum with both rectangular and tapered box beam structures. Design variables include taper ratio, nonstructural segment weights and box beam dimensions. The paper shows that even when starting with an acceptable baseline design, a significant amount of weight reduction is possible while satisfying all the constraints for blades with rectangular and tapered box beams.
NASA Astrophysics Data System (ADS)
Wissman, J.; Finkenauer, L.; Deseri, L.; Majidi, C.
2014-10-01
We introduce a dielectric elastomer actuator (DEA) composed of liquid-phase Gallium-Indium (GaIn) alloy electrodes embedded between layers of poly(dimethylsiloxane) (PDMS) and examine its mechanics using a specialized elastic shell theory. Residual stresses in the dielectric and sealing layers of PDMS cause the DEA to deform into a saddle-like geometry (Gaussian curvature K <0). Applying voltage Φ to the liquid metal electrodes induces electrostatic pressure (Maxwell stress) on the dielectric and relieves some of the residual stress. This reduces the longitudinal bending curvature and corresponding angle of deflection ϑ. Treating the elastomer as an incompressible, isotropic, NeoHookean solid, we develop a theory based on the principle of minimum potential energy to predict the principal curvatures as a function of Φ. Based on this theory, we predict a dependency of ϑ on Φ that is in strong agreement with experimental measurements performed on a GaIn-PDMS composite. By accurately modeling electromechanical coupling in a soft-matter DEA, this theory can inform improvements in design and fabrication.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wissman, J., E-mail: jwissman@andrew.cmu.edu; Finkenauer, L.; Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
We introduce a dielectric elastomer actuator (DEA) composed of liquid-phase Gallium-Indium (GaIn) alloy electrodes embedded between layers of poly(dimethylsiloxane) (PDMS) and examine its mechanics using a specialized elastic shell theory. Residual stresses in the dielectric and sealing layers of PDMS cause the DEA to deform into a saddle-like geometry (Gaussian curvature K<0). Applying voltage Φ to the liquid metal electrodes induces electrostatic pressure (Maxwell stress) on the dielectric and relieves some of the residual stress. This reduces the longitudinal bending curvature and corresponding angle of deflection ϑ. Treating the elastomer as an incompressible, isotropic, NeoHookean solid, we develop a theorymore » based on the principle of minimum potential energy to predict the principal curvatures as a function of Φ. Based on this theory, we predict a dependency of ϑ on Φ that is in strong agreement with experimental measurements performed on a GaIn-PDMS composite. By accurately modeling electromechanical coupling in a soft-matter DEA, this theory can inform improvements in design and fabrication.« less
Does a Local B-Minimum Appear in the Tail Current Sheet During a Substorm Growth Phase?
NASA Astrophysics Data System (ADS)
Sergeev, V. A.; Gordeev, E. I.; Merkin, V. G.; Sitnov, M. I.
2018-03-01
Magnetic configurations with dBz/dr > 0 in the midtail current sheet are potentially unstable to various instabilities associated with the explosive substorm onset. Their existence is hard to confirm with observations of magnetospheric spacecraft. Here we use remote sensing by low-altitude spacecraft that measured the loss cone filling rate during electron-rich solar particle event, providing information about magnetic properties of the tail current sheet. We found a latitudinally localized anisotropic 30 keV electron loss cone region embedded inside an extended region of isotropic solar electron precipitation. It was persistently observed for more than 0.5 h during isolated growth phase event by six Polar Operational Environmental Satellites spacecraft, which crossed the premidnight auroral oval. The embedded anisotropic region was observed 1° poleward of the outer radiation belt boundary over 4-5 h wide magnetic local time sector, suggesting a persistent ridge-type Bz2/j maximum in the equatorial plasma sheet at distances 15-20 RE. We discuss infrequent observations of such events taking into account recent results of global magnetohydrodynamic simulations.
Ma, Yujie; Rajendran, Prayanka; Blum, Christian; Cesa, Yanina; Gartmann, Nando; Brühwiler, Dominik; Subramaniam, Vinod
2011-04-01
The infiltration of enhanced green fluorescent protein (EGFP) into nanochannels of different diameters in mesoporous silica particles was studied in detail by fluorescence microspectroscopy at room temperature. Silica particles from the MCM-41, ASNCs and SBA-15 families possessing nanometer-sized (3-8 nm in diameter) channels, comparable to the dimensions of the infiltrated guest protein EGFP (barrel structure with dimensions of 2.4 nm × 4.2 nm), were used as hosts. We found that it is necessary to first functionalize the surfaces of the silica particles with an amino-silane for effective encapsulation of EGFP. We demonstrated successful infiltration of the protein into the nanochannels based on fluorescence microspectroscopy and loading capacity calculations, even for nanochannel diameters approaching the protein dimensions. We studied the spatial distributions of the EGFPs within the silica particles by confocal laser scanning microscopy (CLSM) and multimode microscopy. Upon infiltration, the fluorescence lifetime drops as expected for an emitter embedded in a high refractive index medium. Further, the spectral properties of EGFP are preserved, confirming the structural integrity of the infiltrated protein. This inorganic-protein host-guest system is an example of a nanobiophotonic hybrid system that may lead to composite materials with novel optical properties. Copyright © 2010 Elsevier Inc. All rights reserved.
Lancaster, Matthew E; Shelhamer, Ryan; Homa, Donald
2013-04-01
Two experiments investigated category inference when categories were composed of correlated or uncorrelated dimensions and the categories overlapped minimally or moderately. When the categories minimally overlapped, the dimensions were strongly correlated with the category label. Following a classification learning phase, subsequent transfer required the selection of either a category label or a feature when one, two, or three features were missing. Experiments 1 and 2 differed primarily in the number of learning blocks prior to transfer. In each experiment, the inference of the category label or category feature was influenced by both dimensional and category correlations, as well as their interaction. The number of cues available at test impacted performance more when the dimensional correlations were zero and category overlap was high. However, a minimal number of cues were sufficient to produce high levels of inference when the dimensions were highly correlated; additional cues had a positive but reduced impact, even when overlap was high. Subjects were generally more accurate in inferring the category label than a category feature regardless of dimensional correlation, category overlap, or number of cues available at test. Whether the category label functioned as a special feature or not was critically dependent upon these embedded correlations, with feature inference driven more strongly by dimensional correlations.
Multicritical points of the O(N) scalar theory in 2 < d < 4 for large N
NASA Astrophysics Data System (ADS)
Katsis, A.; Tetradis, N.
2018-05-01
We solve analytically the renormalization-group equation for the potential of the O (N)-symmetric scalar theory in the large-N limit and in dimensions 2 < d < 4, in order to look for nonperturbative fixed points that were found numerically in a recent study. We find new real solutions with singularities in the higher derivatives of the potential at its minimum, and complex solutions with branch cuts along the negative real axis.
A map for heavy inertial particles in fluid flows
NASA Astrophysics Data System (ADS)
Vilela, Rafael D.; de Oliveira, Vitor M.
2017-06-01
We introduce a map which reproduces qualitatively many fundamental properties of the dynamics of heavy particles in fluid flows. These include a uniform rate of decrease of volume in phase space, a slow-manifold effective dynamics when the single parameter s (analogous of the Stokes number) approaches zero, the possibility of fold caustics in the "velocity field", and a minimum, as a function of s, of the Lyapunov (Kaplan-Yorke) dimension of the attractor where particles accumulate.
Design of composite scaffolds and three-dimensional shape analysis for tissue-engineered ear
Cervantes, Thomas M.; Bassett, Erik K.; Tseng, Alan; Kimura, Anya; Roscioli, Nick; Randolph, Mark A.; Vacanti, Joseph P.; Hadlock, Theresa A.; Gupta, Rajiv; Pomerantseva, Irina; Sundback, Cathryn A.
2013-01-01
Engineered cartilage is a promising option for auricular reconstruction. We have previously demonstrated that a titanium wire framework within a composite collagen ear-shaped scaffold helped to maintain the gross dimensions of the engineered ear after implantation, resisting the deformation forces encountered during neocartilage maturation and wound healing. The ear geometry was redesigned to achieve a more accurate aesthetic result when implanted subcutaneously in a nude rat model. A non-invasive method was developed to assess size and shape changes of the engineered ear in three dimensions. Computer models of the titanium framework were obtained from CT scans before and after implantation. Several parameters were measured including the overall length, width and depth, the minimum intrahelical distance and overall curvature values for each beam section within the framework. Local curvature values were measured to gain understanding of the bending forces experienced by the framework structure in situ. Length and width changed by less than 2%, whereas the depth decreased by approximately 8% and the minimum intrahelical distance changed by approximately 12%. Overall curvature changes identified regions most susceptible to deformation. Eighty-nine per cent of local curvature measurements experienced a bending moment less than 50 µN-m owing to deformation forces during implantation. These quantitative shape analysis results have identified opportunities to improve shape fidelity of engineered ear constructs. PMID:23904585
Fast Minimum Variance Beamforming Based on Legendre Polynomials.
Bae, MooHo; Park, Sung Bae; Kwon, Sung Jae
2016-09-01
Currently, minimum variance beamforming (MV) is actively investigated as a method that can improve the performance of an ultrasound beamformer, in terms of the lateral and contrast resolution. However, this method has the disadvantage of excessive computational complexity since the inverse spatial covariance matrix must be calculated. Some noteworthy methods among various attempts to solve this problem include beam space adaptive beamforming methods and the fast MV method based on principal component analysis, which are similar in that the original signal in the element space is transformed to another domain using an orthonormal basis matrix and the dimension of the covariance matrix is reduced by approximating the matrix only with important components of the matrix, hence making the inversion of the matrix very simple. Recently, we proposed a new method with further reduced computational demand that uses Legendre polynomials as the basis matrix for such a transformation. In this paper, we verify the efficacy of the proposed method through Field II simulations as well as in vitro and in vivo experiments. The results show that the approximation error of this method is less than or similar to those of the above-mentioned methods and that the lateral response of point targets and the contrast-to-speckle noise in anechoic cysts are also better than or similar to those methods when the dimensionality of the covariance matrices is reduced to the same dimension.
Radiative Transfer and Satellite Remote Sensing of Cirrus Clouds Using FIRE-2-IFO Data
NASA Technical Reports Server (NTRS)
2000-01-01
Under the support of the NASA grant, we have developed a new geometric-optics model (GOM2) for the calculation of the single-scattering and polarization properties for arbitrarily oriented hexagonal ice crystals. From comparisons with the results computed by the finite difference time domain (FDTD) method, we show that the novel geometric-optics can be applied to the computation of the extinction cross section and single-scattering albedo for ice crystals with size parameters along the minimum dimension as small as approximately 6. We demonstrate that the present model converges to the conventional ray tracing method for large size parameters and produces single-scattering results close to those computed by the FDTD method for size parameters along the minimum dimension smaller than approximately 20. We demonstrate that neither the conventional geometric optics method nor the Lorenz-Mie theory can be used to approximate the scattering, absorption, and polarization features for hexagonal ice crystals with size parameters from approximately 5 to 20. On the satellite remote sensing algorithm development and validation, we have developed a numerical scheme to identify multilayer cirrus cloud systems using AVHRR data. We have applied this scheme to the satellite data collected over the FIRE-2-IFO area during nine overpasses within seven observation dates. Determination of the threshold values used in the detection scheme are based on statistical analyses of these satellite data.
Design of composite scaffolds and three-dimensional shape analysis for tissue-engineered ear.
Cervantes, Thomas M; Bassett, Erik K; Tseng, Alan; Kimura, Anya; Roscioli, Nick; Randolph, Mark A; Vacanti, Joseph P; Hadlock, Theresa A; Gupta, Rajiv; Pomerantseva, Irina; Sundback, Cathryn A
2013-10-06
Engineered cartilage is a promising option for auricular reconstruction. We have previously demonstrated that a titanium wire framework within a composite collagen ear-shaped scaffold helped to maintain the gross dimensions of the engineered ear after implantation, resisting the deformation forces encountered during neocartilage maturation and wound healing. The ear geometry was redesigned to achieve a more accurate aesthetic result when implanted subcutaneously in a nude rat model. A non-invasive method was developed to assess size and shape changes of the engineered ear in three dimensions. Computer models of the titanium framework were obtained from CT scans before and after implantation. Several parameters were measured including the overall length, width and depth, the minimum intrahelical distance and overall curvature values for each beam section within the framework. Local curvature values were measured to gain understanding of the bending forces experienced by the framework structure in situ. Length and width changed by less than 2%, whereas the depth decreased by approximately 8% and the minimum intrahelical distance changed by approximately 12%. Overall curvature changes identified regions most susceptible to deformation. Eighty-nine per cent of local curvature measurements experienced a bending moment less than 50 µN-m owing to deformation forces during implantation. These quantitative shape analysis results have identified opportunities to improve shape fidelity of engineered ear constructs.
Chen, Wen; Ling, Li; Renzaho, Andre M N
2017-03-15
To assess the relationship between social integration and physical and mental health among humanitarian migrants (HMs) in Australia. We used the recently released first wave of data from the 2013 'Building a New Life in Australia' survey, which is an ongoing nationwide longitudinal study. A total of 2399 HMs participated in the survey. Self-rated physical health was measured using four items selected from the SF-36 which is a generic measure of health status. The 6-item Kessler Screening Scale for Psychological Distress (K6) was used to measure mental health. Social integration was measured using four dimensions: economic integration, acculturation, social capital and self-identity. More than half (63%), 47% and 49% of participants self-rated well on the general health, physical function and role-physical dimensions, respectively and 46% reported not having any bodily pain. Seventeen per cent of participants had a serious mental illness. There was a positive relationship between social integration and physical and mental health. That is, factors associated with better health included less financial hardship (economic integration dimension), better English proficiency and self-sufficiency (acculturation dimension), having the capacity to communicate with locals, having friends from different ethnic/religious groups and attending a place of worship weekly or more often (social capital dimension) and feeling welcomed and having a strong sense of belonging in Australia (self-identity dimension). Using a more comprehensive framework of social integration, we found that greater social integration was associated with better physical and mental health outcomes among HMs. Social integration should be embedded in HMs' resettlement programmes in order to reduce migration-related health inequities. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Chen, Wen; Ling, Li; Renzaho, Andre M N
2017-01-01
Objectives To assess the relationship between social integration and physical and mental health among humanitarian migrants (HMs) in Australia. Design, setting and participants We used the recently released first wave of data from the 2013 ‘Building a New Life in Australia’ survey, which is an ongoing nationwide longitudinal study. A total of 2399 HMs participated in the survey. Main outcome measures Self-rated physical health was measured using four items selected from the SF-36 which is a generic measure of health status. The 6-item Kessler Screening Scale for Psychological Distress (K6) was used to measure mental health. Social integration was measured using four dimensions: economic integration, acculturation, social capital and self-identity. Results More than half (63%), 47% and 49% of participants self-rated well on the general health, physical function and role-physical dimensions, respectively and 46% reported not having any bodily pain. Seventeen per cent of participants had a serious mental illness. There was a positive relationship between social integration and physical and mental health. That is, factors associated with better health included less financial hardship (economic integration dimension), better English proficiency and self-sufficiency (acculturation dimension), having the capacity to communicate with locals, having friends from different ethnic/religious groups and attending a place of worship weekly or more often (social capital dimension) and feeling welcomed and having a strong sense of belonging in Australia (self-identity dimension). Conclusions Using a more comprehensive framework of social integration, we found that greater social integration was associated with better physical and mental health outcomes among HMs. Social integration should be embedded in HMs' resettlement programmes in order to reduce migration-related health inequities. PMID:28298368
Holistic processing of impossible objects: evidence from Garner's speeded-classification task.
Freud, Erez; Avidan, Galia; Ganel, Tzvi
2013-12-18
Holistic processing, the decoding of the global structure of a stimulus while the local parts are not explicitly represented, is a basic characteristic of object perception. The current study was aimed to test whether such a representation could be created even for objects that violate fundamental principles of spatial organization, namely impossible objects. Previous studies argued that these objects cannot be represented holistically in long-term memory because they lack coherent 3D structure. Here, we utilized Garner's speeded classification task to test whether the perception of possible and impossible objects is mediated by similar holistic processing mechanisms. To this end, participants were asked to make speeded classifications of one object dimension while an irrelevant dimension was kept constant (baseline condition) or when this dimension varied (filtering condition). It is well accepted that ignoring the irrelevant dimension is impossible when holistic perception is mandatory, thus the extent of Garner interference in performance between the baseline and filtering conditions serves as an index of holistic processing. Critically, in Experiment 1, similar levels of Garner interference were found for possible and impossible objects implying holistic perception of both object types. Experiment 2 extended these results and demonstrated that even when depth information was explicitly processed, participants were still unable to process one dimension (width/depth) while ignoring the irrelevant dimension (depth/width, respectively). The results of Experiment 3 replicated the basic pattern found in Experiments 1 and 2 using a novel set of object exemplars. In Experiment 4, we used possible and impossible versions of the Penrose triangles in which information about impossibility is embedded in the internal elements of the objects which participant were explicitly asked to judge. As in Experiments 1-3, similar Garner interference was found for possible and impossible objects. Taken together, these findings emphasize the centrality of holistic processing style in object perception and suggest that it applies even for atypical stimuli such as impossible objects. Copyright © 2013 Elsevier B.V. All rights reserved.
Stroop interference in a delayed match-to-sample task: evidence for semantic competition
Sturz, Bradley R.; Green, Marshall L.; Locker, Lawrence; Boyer, Ty W.
2013-01-01
Discussions of the source of the Stroop interference effect continue to pervade the literature. Semantic competition posits that interference results from competing semantic activation of word and color dimensions of the stimulus prior to response selection. Response competition posits that interference results from competing responses for articulating the word dimension vs. the color dimension at the time of response selection. We embedded Stroop stimuli into a delayed match-to-sample (DMTS) task in an attempt to test semantic and response competition accounts of the interference effect. Participants viewed a sample color word in black or colored fonts that were congruent or incongruent with respect to the color word itself. After a 5 s delay, participants were presented with two targets (i.e., a match and a foil) and were instructed to select the correct match. We probed each dimension independently during target presentations via color targets (i.e., two colors) or word targets (i.e., two words) and manipulated whether the semantic content of the foil was related to the semantic content of the irrelevant sample dimension (e.g., word sample “red” in blue font with the word “red” as the match and the word “blue” as the foil). We provide evidence for Stroop interference such that response times (RTs) increased for incongruent trials even in the presence of a response option with semantic content unrelated to the semantic content of the irrelevant sample dimension. Accuracy also deteriorated during the related foil trials. A follow-up experiment with a 10 s delay between sample and targets replicated the results. Results appear to provide converging evidence for Stroop interference in a DMTS task in a manner that is consistent with an explanation based upon semantic competition and inconsistent with an explanation based upon response competition. PMID:24298264
You Don’t See What I See: Individual Differences in the Perception of Meaning from Visual Stimuli
Partos, Timea R.; Cropper, Simon J.; Rawlings, David
2016-01-01
Everyone has their own unique version of the visual world and there has been growing interest in understanding the way that personality shapes one’s perception. Here, we investigated meaningful visual experiences in relation to the personality dimension of schizotypy. In a novel approach to this issue, a non-clinical sample of subjects (total n = 197) were presented with calibrated images of scenes, cartoons and faces of varying visibility embedded in noise; the spatial properties of the images were constructed to mimic the natural statistics of the environment. In two experiments, subjects were required to indicate what they saw in a large number of unique images, both with and without actual meaningful structure. The first experiment employed an open-ended response paradigm and used a variety of different images in noise; the second experiment only presented a series of faces embedded in noise, and required a forced-choice response from the subjects. The results in all conditions indicated that a high positive schizotypy score was associated with an increased tendency to perceive complex meaning in images comprised purely of random visual noise. Individuals high in positive schizotypy seemed to be employing a looser criterion (response bias) to determine what constituted a ‘meaningful’ image, while also being significantly less sensitive at the task than those low in positive schizotypy. Our results suggest that differences in perceptual performance for individuals high in positive schizotypy are not related to increased suggestibility or susceptibility to instruction, as had previously been suggested. Instead, the observed reductions in sensitivity along with increased response bias toward seeing something that is not there, indirectly implicated subtle neurophysiological differences associated with the personality dimension of schizotypy, that are theoretically pertinent to the continuum of schizophrenia and hallucination-proneness. PMID:26954696
NASA Astrophysics Data System (ADS)
Pinto, F.; Meo, M.
2017-06-01
The ability to absorb a large amount of energy during an impact event without generating critical damages represents a key feature of new generation composite systems. Indeed, the intrinsic layered nature of composite materials allows the embodiment of specific hybrid plies within the stacking sequence that can be exploited to increase impact resistance and damping of the entire structure without dramatic weight increase. This work is based on the development of an impact-resistant hybrid composite obtained by including a thin layer of Non-Newtonian silica based fluid in a carbon fibres reinforced polymer (CFRP) laminate. This hybrid phase is able to respond to an external solicitation by activating an order-disorder transition that thickens the fluid increasing its viscosity, hence dissipating the energy impact without any critical failure. Several Shear Thickening Fluids (STFs) were manufactured by changing the dimensions of the particles that constitute the disperse phase and their concentrations into the continuous phase. The dynamic viscosity of the different STFs was evaluated via rheometric tests, observing both shear thinning and shear thickening effects depending on the concentration of silica particles. The solutions were then embedded as an active layer within the stacking sequence to manufacture the hybrid CFRP laminates with different embedded STFs. Free vibration tests were carried out in order to assess the damping properties of the different laminates, while low velocity impact tests were used to evaluate their impact properties. Results indicate that the presence of the non-Newtonian fluid is able to absorb up to 45 % of the energy during an impact event for impacts at 2.5 m/s depending on the different concentrations and particles dimensions. These results were confirmed via C-Scan analyses to assess the extent of the internal delamination.
Thapa, N B; Shah, S; Pradhan, A; Rijal, K; Pradhan, A; Basnet, S
2015-01-01
Background Ultrasonography is one of the most common imaging modality to measure dimensions of visceral organs in children. However, the normal limit of size of visceral organs according to age and body habitus has not been specified in the standard textbooks. This might result in under detection of organomegaly in pediatrics population. Objective The objective of this study was to determine the normal range of dimensions for the liver, spleen, and kidney in healthy children. Method This is prospective cross-sectional, hospital-based study done at Tertiary-care teaching hospital. Participants included 272 pediatric subjects (152 male and 120 female) with normal physical or sonographic findings who were examined because of problems unrelated to the measured organs. The subjects were one month to 15 year (180 months) old. All measured organs were sonographically normal. Relationships of the dimensions of these organs with sex, age, body weight and height were investigated. Limits of normal dimensions of these organs were defined. Result Normal length of liver, kidneys and spleen were obtained sonographically for 272 children (152 male [55.9%] and 120 female [44.1%]) in the age group from 1 months to 15 (180 months) years. The mean age was 45.78 months (SD, 44.73). The measured dimensions of all these organs showed highest correlation with height and age so the descriptive analysis of the organ dimensions (mean, minimum, and maximum values, SD and 5th and 95th percentiles) were expressed in 10 age groups along with height range of the included children. The mean length of right kidney was shorter than the left kidney length, and the difference was statistically significant (p = 0.001). Conclusion This study provides practical and comprehensive guide to the normal visceral organ dimension in pediatric population. The normal range limit of the liver, spleen, and kidney determined in this study could be used as a reference in daily practice in local radiology clinics.
Interference-mediated synaptonemal complex formation with embedded crossover designation
Zhang, Liangran; Espagne, Eric; de Muyt, Arnaud; Zickler, Denise; Kleckner, Nancy E.
2014-01-01
Biological systems exhibit complex patterns at length scales ranging from the molecular to the organismic. Along chromosomes, events often occur stochastically at different positions in different nuclei but nonetheless tend to be relatively evenly spaced. Examples include replication origin firings, formation of chromatin loops along chromosome axes and, during meiosis, localization of crossover recombination sites (“crossover interference”). We present evidence in the fungus Sordaria macrospora that crossover interference is part of a broader pattern that includes synaptonemal complex (SC) nucleation. This pattern comprises relatively evenly spaced SC nucleation sites, among which a subset are crossover sites that show a classical interference distribution. This pattern ensures that SC forms regularly along the entire length of the chromosome as required for the maintenance of homolog pairing while concomitantly having crossover interactions locally embedded within the SC structure as required for both DNA recombination and structural events of chiasma formation. This pattern can be explained by a threshold-based designation and spreading interference process. This model can be generalized to give diverse types of related and/or partially overlapping patterns, in two or more dimensions, for any type of object. PMID:25380597
Biodiversity maintenance in food webs with regulatory environmental feedbacks.
Bagdassarian, Carey K; Dunham, Amy E; Brown, Christopher G; Rauscher, Daniel
2007-04-21
Although the food web is one of the most fundamental and oldest concepts in ecology, elucidating the strategies and structures by which natural communities of species persist remains a challenge to empirical and theoretical ecologists. We show that simple regulatory feedbacks between autotrophs and their environment when embedded within complex and realistic food-web models enhance biodiversity. The food webs are generated through the niche-model algorithm and coupled with predator-prey dynamics, with and without environmental feedbacks at the autotroph level. With high probability and especially at lower, more realistic connectance levels, regulatory environmental feedbacks result in fewer species extinctions, that is, in increased species persistence. These same feedback couplings, however, also sensitize food webs to environmental stresses leading to abrupt collapses in biodiversity with increased forcing. Feedback interactions between species and their material environments anchor food-web persistence, adding another dimension to biodiversity conservation. We suggest that the regulatory features of two natural systems, deep-sea tubeworms with their microbial consortia and a soil ecosystem manifesting adaptive homeostatic changes, can be embedded within niche-model food-web dynamics.
Secure steganography designed for mobile platforms
NASA Astrophysics Data System (ADS)
Agaian, Sos S.; Cherukuri, Ravindranath; Sifuentes, Ronnie R.
2006-05-01
Adaptive steganography, an intelligent approach to message hiding, integrated with matrix encoding and pn-sequences serves as a promising resolution to recent security assurance concerns. Incorporating the above data hiding concepts with established cryptographic protocols in wireless communication would greatly increase the security and privacy of transmitting sensitive information. We present an algorithm which will address the following problems: 1) low embedding capacity in mobile devices due to fixed image dimensions and memory constraints, 2) compatibility between mobile and land based desktop computers, and 3) detection of stego images by widely available steganalysis software [1-3]. Consistent with the smaller available memory, processor capabilities, and limited resolution associated with mobile devices, we propose a more magnified approach to steganography by focusing adaptive efforts at the pixel level. This deeper method, in comparison to the block processing techniques commonly found in existing adaptive methods, allows an increase in capacity while still offering a desired level of security. Based on computer simulations using high resolution, natural imagery and mobile device captured images, comparisons show that the proposed method securely allows an increased amount of embedding capacity but still avoids detection by varying steganalysis techniques.
Description and analysis of cored hydraulic fractures -- Lost Hills field, Kern County, California
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fast, R.E.; Murer, A.S.; Timmer, R.S.
1994-05-01
An inclined observation well was drilled in shallow (2,000 ft) Opal-A diatomite. Seven sand-propped hydraulic fractures were cored and recovered. The hydraulic fractures were found within 5[degree] of the azimuth measured with tilt meters and were tilted 15[degree] from vertical, oriented perpendicular to the formation bedding dip. Hydraulic fractures widths ranged from less than one sand grain (40/60 mesh) to 0.4 in. Scanning electron microscopy (SEM) examination of fracture faces showed no damage to the matrix from proppant embedment or compaction, and no evidence of guard residue was detected in the proppant pack or on the formation face. Fractures appearmore » to be considerably longer than modeled. Three closely spaced fractures are interpreted to be branches of a single hydraulic fracture treatment. This paper presents a description of the fractures recovered during coring in Well OO2. Findings related to fracture dimensions and orientations, fracture sources, fracture permeability measurements, and fracture characteristics (proppant embedment, presence of gel residue) are presented. Implications related to field development are discussed.« less
Roep, Dirk; Wiskerke, Johannes S C
Based on the reconstruction of the development of 14 food supply chain initiatives in 7 European countries, we developed a conceptual framework that demonstrates that the process of increasing the sustainability of food supply chains is rooted in strategic choices regarding governance , embedding, and marketing and in the coordination of these three dimensions that are inextricably interrelated. The framework also shows that when seeking to further develop an initiative (e.g., through scaling up or product diversification) these interrelations need continuous rebalancing. We argue that the framework can serve different purposes: it can be used as an analytical tool by researchers studying food supply chain dynamics, as a policy tool by policymakers that want to support the development of sustainable food supply chains, and as a reflexive tool by practitioners and their advisors to help them to position themselves, develop a clear strategy, find the right allies, develop their skills, and build the capacities that they need. In this paper, we elaborate upon the latter function of the framework and illustrate this briefly with empirical evidence from three of the initiatives that we studied.
Network embedding-based representation learning for single cell RNA-seq data.
Li, Xiangyu; Chen, Weizheng; Chen, Yang; Zhang, Xuegong; Gu, Jin; Zhang, Michael Q
2017-11-02
Single cell RNA-seq (scRNA-seq) techniques can reveal valuable insights of cell-to-cell heterogeneities. Projection of high-dimensional data into a low-dimensional subspace is a powerful strategy in general for mining such big data. However, scRNA-seq suffers from higher noise and lower coverage than traditional bulk RNA-seq, hence bringing in new computational difficulties. One major challenge is how to deal with the frequent drop-out events. The events, usually caused by the stochastic burst effect in gene transcription and the technical failure of RNA transcript capture, often render traditional dimension reduction methods work inefficiently. To overcome this problem, we have developed a novel Single Cell Representation Learning (SCRL) method based on network embedding. This method can efficiently implement data-driven non-linear projection and incorporate prior biological knowledge (such as pathway information) to learn more meaningful low-dimensional representations for both cells and genes. Benchmark results show that SCRL outperforms other dimensional reduction methods on several recent scRNA-seq datasets. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.
Vapor chamber with hollow condenser tube heat sink
NASA Astrophysics Data System (ADS)
Ong, K. S.; Haw, P. L.; Lai, K. C.; Tan, K. H.
2017-04-01
Heat pipes are heat transfer devices capable of transferring large quantities of heat effectively and efficiently. A vapor chamber (VC) is a flat heat pipe. A novel VC with hollow condenser tubes embedded on the top of it is proposed. This paper reports on the experimental thermal performance of three VC devices embedded with hollow tubes and employed as heat sinks. The first device consisted of a VC with a single hollow tube while the other two VCs had an array of multi-tubes with different tube lengths. All three devices were tested under natural and force air convection cooling. An electrical resistance heater was employed to provide power inputs of 10 and 40 W. Surface temperatures were measured with thermocouple probes at different locations around the devices. The results show that temperatures increased with heater input while total device thermal resistances decreased. Force convection results in lower temperatures and lower resistance. Dry-out occurs at high input power and with too much condensing area. There appears to be an optimum fill ratio which depended upon dimensions of the VC and also heating power.
Maximum nonlocality and minimum uncertainty using magic states
NASA Astrophysics Data System (ADS)
Howard, Mark
2015-04-01
We prove that magic states from the Clifford hierarchy give optimal solutions for tasks involving nonlocality and entropic uncertainty with respect to Pauli measurements. For both the nonlocality and uncertainty tasks, stabilizer states are the worst possible pure states, so our solutions have an operational interpretation as being highly nonstabilizer. The optimal strategy for a qudit version of the Clauser-Horne-Shimony-Holt game in prime dimensions is achieved by measuring maximally entangled states that are isomorphic to single-qudit magic states. These magic states have an appealingly simple form, and our proof shows that they are "balanced" with respect to all but one of the mutually unbiased stabilizer bases. Of all equatorial qudit states, magic states minimize the average entropic uncertainties for collision entropy and also, for small prime dimensions, min-entropy, a fact that may have implications for cryptography.
An exact noniterative linear method for locating sources based on measuring receiver arrival times.
Militello, C; Buenafuente, S R
2007-06-01
In this paper an exact, linear solution to the source localization problem based on the time of arrival at the receivers is presented. The method is unique in that the source's position can be obtained by solving a system of linear equations, three for a plane and four for a volume. This simplification means adding an additional receiver to the minimum mathematically required (3+1 in two dimensions and 4+1 in three dimensions). The equations are easily worked out for any receiver configuration and their geometrical interpretation is straightforward. Unlike other methods, the system of reference used to describe the receivers' positions is completely arbitrary. The relationship between this method and previously published ones is discussed, showing how the present, more general, method overcomes nonlinearity and unknown dependency issues.
Mendoza, Fernando; Valous, Nektarios A; Allen, Paul; Kenny, Tony A; Ward, Paddy; Sun, Da-Wen
2009-02-01
This paper presents a novel and non-destructive approach to the appearance characterization and classification of commercial pork, turkey and chicken ham slices. Ham slice images were modelled using directional fractal (DF(0°;45°;90°;135°)) dimensions and a minimum distance classifier was adopted to perform the classification task. Also, the role of different colour spaces and the resolution level of the images on DF analysis were investigated. This approach was applied to 480 wafer thin ham slices from four types of hams (120 slices per type): i.e., pork (cooked and smoked), turkey (smoked) and chicken (roasted). DF features were extracted from digitalized intensity images in greyscale, and R, G, B, L(∗), a(∗), b(∗), H, S, and V colour components for three image resolution levels (100%, 50%, and 25%). Simulation results show that in spite of the complexity and high variability in colour and texture appearance, the modelling of ham slice images with DF dimensions allows the capture of differentiating textural features between the four commercial ham types. Independent DF features entail better discrimination than that using the average of four directions. However, DF dimensions reveal a high sensitivity to colour channel, orientation and image resolution for the fractal analysis. The classification accuracy using six DF dimension features (a(90°)(∗),a(135°)(∗),H(0°),H(45°),S(0°),H(90°)) was 93.9% for training data and 82.2% for testing data.
The Effect of Condensing Steam Turbine Exhaust Hood Body Geometry on Exhaust Performance Efficiency
NASA Astrophysics Data System (ADS)
Gribin, V. G.; Paramonov, A. N.; Mitrokhova, O. M.
2018-06-01
The article presents data from combined numerical and experimental investigations of the effect that the overall dimensions of the exhaust hood of a steam turbine with an underslung condenser has on the aerodynamic losses in the hood. Owing to the properly selected minimum permissible overall dimensions of the exhaust hood, more efficient operation of this turbine component is achieved, better vibration stability of the turbine set shaft line is obtained, and lower costs are required for arranging the steam turbine plant in the turbine building. Experiments have shown that the main overall dimensions of the hood body have a determining effect on the exhaust hood flow path profile and on its aerodynamic performance. Owing to properly selected ratios between the exhaust hood body main sizes without a diffuser, a total loss coefficient equal to approximately unity has been obtained. By using an axial-radial diffuser, the energy loss can be decreased by 30-40% depending on the geometrical parameters and level of velocities in the inlet section of a hood having the optimal overall dimensions. By using the obtained results, it becomes possible to evaluate the overall dimensions necessary for achieving the maximal aerodynamic hood efficiency and, as a consequence, to obtain better technical and economic indicators of the turbine plant as a whole already at the initial stage of its designing. If a need arises to select overall dimensions smaller than their optimal values, the increase of energy loss can be estimated using the presented dependences. The cycle of investigations was carried out on the experimental setups available in the fundamental research laboratory of the Moscow Power Engineering Institute National University's Department of Steam and Gas Turbines with due regard to the operating parameters and similarity criteria.
Canine and Premolar Root Dimensions in Chinese. A Reference for Osteoodontokeratoprosthesis Surgery.
Sun, Stella Yue; Yeo, Woon Chee; Tay, Andrew Ban Guan; Tan, Donald Tiang Hwee; Tan, Danny Ben Poon
2018-01-01
Osteoodontokeratoprosthesis (OOKP) surgery is used to restore vision in end-stage corneal disorders, where an autogenous tooth supporting an optical cylinder is implanted through the cornea under a buccal mucosal graft. The ideal tooth for OOKP is a healthy single-rooted permanent tooth with sufficient buccolingual/palatal root diameter to accommodate an optical cylinder. The aim of this study was to determine the buccolingual/palatal diameters of canine and premolar roots in Chinese, for selection of teeth for OOKP surgery. This was an anatomical study on root dimensions of extracted intact teeth. Extracted canine and premolar teeth (excluding maxillary first premolars) were collected and the buccolingual/palatal and mesiodistal diameters of the root at the cervical line and at 2-mm intervals below the cervical line were measured with Vernier calipers. Other measurements included total tooth length, crown buccolingual/palatal diameter, and root length. Mean and minimum buccolingual/palatal root diameters were compiled for each 2-mm interval. A total of 415 extracted teeth (198 male, 217 female) were collected and measured. Recorded dimensions of keratoprostheses in 55 previous OOKP surgeries were used to establish acceptable lamina dimensions to ascertain root size adequacy. Premolars in Chinese female patients were undersized in a small minority. Minimal dimensions of teeth were insufficient if at 6 mm root level, the buccolingual/palatal width was less than 5 mm, or the mesiodistal width was less than 3 mm. This was noted in female mandibular first premolars (5.6%), maxillary second premolars (4.5%), and mandibular second premolars (1.5%). Canines have adequate dimensions for OOKP surgery. However, premolars in Chinese females may be undersized in a small minority. Copyright 2017 Asia-Pacific Academy of Ophthalmology.
Study of the inhomogeneity of critical current under in-situ tensile stress for YBCO tape
NASA Astrophysics Data System (ADS)
Zhu, Y. P.; Chen, W.; Zhang, H. Y.; Liu, L. Y.; Pan, X. F.; Yang, X. S.; Zhao, Y.
2018-07-01
A Hall sensor system was used to measure the local critical current of YBCO tape with high spatial resolution under in-situ tensile stress. The hot spot generation and minimum quench energy of YBCO tape, which depended on the local critical current, was calculated through the thermoelectric coupling model. With the increase in tensile stress, the cracks which have different dimensions and critical current degradation arose more frequently and lowered the thermal stability of the YBCO tape.
NASA Technical Reports Server (NTRS)
Likins, P. W.
1974-01-01
Equations of motion are derived for use in simulating a spacecraft or other complex electromechanical system amenable to idealization as a set of hinge-connected rigid bodies of tree topology, with rigid axisymmetric rotors and nonrigid appendages attached to each rigid body in the set. In conjunction with a previously published report on finite-element appendage vibration equations, this report provides a complete minimum-dimension formulation suitable for generic programming for digital computer numerical integration.
Maximal violation of Clauser-Horne-Shimony-Holt inequality for four-level systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fu Libin; Max-Planck-Institute for the Physics of Complex Systems, Noethnitzer Strasse 38, 01187 Dresden; Chen Jingling
2004-03-01
Clauser-Horne-Shimony-Holt inequality for bipartite systems of four dimensions is studied in detail by employing the unbiased eight-port beam splitters measurements. The uniform formulas for the maximum and minimum values of this inequality for such measurements are obtained. Based on these formulas, we show that an optimal nonmaximally entangled state is about 6% more resistant to noise than the maximally entangled one. We also give the optimal state and the optimal angles which are important for experimental realization.
Hydrodynamics of the Dirac spectrum
Liu, Yizhuang; Warchoł, Piotr; Zahed, Ismail
2015-12-15
We discuss a hydrodynamical description of the eigenvalues of the Dirac spectrum in even dimensions in the vacuum and in the large N (volume) limit. The linearized hydrodynamics supports sound waves. The hydrodynamical relaxation of the eigenvalues is captured by a hydrodynamical (tunneling) minimum configuration which follows from a pertinent form of Euler equation. As a result, the relaxation from a phase of unbroken chiral symmetry to a phase of broken chiral symmetry occurs over a time set by the speed of sound.
Osborn, Sarah; Zulian, Patrick; Benson, Thomas; ...
2018-01-30
This work describes a domain embedding technique between two nonmatching meshes used for generating realizations of spatially correlated random fields with applications to large-scale sampling-based uncertainty quantification. The goal is to apply the multilevel Monte Carlo (MLMC) method for the quantification of output uncertainties of PDEs with random input coefficients on general and unstructured computational domains. We propose a highly scalable, hierarchical sampling method to generate realizations of a Gaussian random field on a given unstructured mesh by solving a reaction–diffusion PDE with a stochastic right-hand side. The stochastic PDE is discretized using the mixed finite element method on anmore » embedded domain with a structured mesh, and then, the solution is projected onto the unstructured mesh. This work describes implementation details on how to efficiently transfer data from the structured and unstructured meshes at coarse levels, assuming that this can be done efficiently on the finest level. We investigate the efficiency and parallel scalability of the technique for the scalable generation of Gaussian random fields in three dimensions. An application of the MLMC method is presented for quantifying uncertainties of subsurface flow problems. Here, we demonstrate the scalability of the sampling method with nonmatching mesh embedding, coupled with a parallel forward model problem solver, for large-scale 3D MLMC simulations with up to 1.9·109 unknowns.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Osborn, Sarah; Zulian, Patrick; Benson, Thomas
This work describes a domain embedding technique between two nonmatching meshes used for generating realizations of spatially correlated random fields with applications to large-scale sampling-based uncertainty quantification. The goal is to apply the multilevel Monte Carlo (MLMC) method for the quantification of output uncertainties of PDEs with random input coefficients on general and unstructured computational domains. We propose a highly scalable, hierarchical sampling method to generate realizations of a Gaussian random field on a given unstructured mesh by solving a reaction–diffusion PDE with a stochastic right-hand side. The stochastic PDE is discretized using the mixed finite element method on anmore » embedded domain with a structured mesh, and then, the solution is projected onto the unstructured mesh. This work describes implementation details on how to efficiently transfer data from the structured and unstructured meshes at coarse levels, assuming that this can be done efficiently on the finest level. We investigate the efficiency and parallel scalability of the technique for the scalable generation of Gaussian random fields in three dimensions. An application of the MLMC method is presented for quantifying uncertainties of subsurface flow problems. Here, we demonstrate the scalability of the sampling method with nonmatching mesh embedding, coupled with a parallel forward model problem solver, for large-scale 3D MLMC simulations with up to 1.9·109 unknowns.« less
NASA Astrophysics Data System (ADS)
Kang, Shouqiang; Ma, Danyang; Wang, Yujing; Lan, Chaofeng; Chen, Qingguo; Mikulovich, V. I.
2017-03-01
To effectively assess different fault locations and different degrees of performance degradation of a rolling bearing with a unified assessment index, a novel state assessment method based on the relative compensation distance of multiple-domain features and locally linear embedding is proposed. First, for a single-sample signal, time-domain and frequency-domain indexes can be calculated for the original vibration signal and each sensitive intrinsic mode function obtained by improved ensemble empirical mode decomposition, and the singular values of the sensitive intrinsic mode function matrix can be extracted by singular value decomposition to construct a high-dimensional hybrid-domain feature vector. Second, a feature matrix can be constructed by arranging each feature vector of multiple samples, the dimensions of each row vector of the feature matrix can be reduced by the locally linear embedding algorithm, and the compensation distance of each fault state of the rolling bearing can be calculated using the support vector machine. Finally, the relative distance between different fault locations and different degrees of performance degradation and the normal-state optimal classification surface can be compensated, and on the basis of the proposed relative compensation distance, the assessment model can be constructed and an assessment curve drawn. Experimental results show that the proposed method can effectively assess different fault locations and different degrees of performance degradation of the rolling bearing under certain conditions.
Development of a magnetic lab-on-a-chip for point-of-care sepsis diagnosis
NASA Astrophysics Data System (ADS)
Schotter, Joerg; Shoshi, Astrit; Brueckl, Hubert
2009-05-01
We present design criteria, operation principles and experimental examples of magnetic marker manipulation for our magnetic lab-on-a-chip prototype. It incorporates both magnetic sample preparation and detection by embedded GMR-type magnetoresistive sensors and is optimized for the automated point-of-care detection of four different sepsis-indicative cytokines directly from about 5 μl of whole blood. The sample volume, magnetic particle size and cytokine concentration determine the microfluidic volume, sensor size and dimensioning of the magnetic gradient field generators. By optimizing these parameters to the specific diagnostic task, best performance is expected with respect to sensitivity, analysis time and reproducibility.
Wang, Xin; Jen, Philip H-S; Wu, Fei-Jian; Chen, Qi-Cai
2007-09-05
In acoustic communication, animals must extract biologically relevant signals that are embedded in noisy environment. The present study examines how weak noise may affect the auditory sensitivity of neurons in the central nucleus of the mouse inferior colliculus (IC) which receives convergent excitatory and inhibitory inputs from both lower and higher auditory centers. Specifically, we studied the frequency sensitivity and minimum threshold of IC neurons using a pure tone probe and a weak white noise masker under forward masking paradigm. For most IC neurons, probe-elicited response was decreased by a weak white noise that was presented at a specific gap (i.e. time window). When presented within this time window, weak noise masking sharpened the frequency tuning curve and increased the minimum threshold of IC neurons. The degree of weak noise masking of these two measurements increased with noise duration. Sharpening of the frequency tuning curve and increasing of the minimum threshold of IC neurons during weak noise masking were mostly mediated through GABAergic inhibition. In addition, sharpening of frequency tuning curve by the weak noise masker was more effective at the high than at low frequency limb. These data indicate that in the real world the ambient noise may improve frequency sensitivity of IC neurons through GABAergic inhibition while inevitably decrease the frequency response range and sensitivity of IC neurons.
Shrot, Yoav; Frydman, Lucio
2011-04-01
A topic of active investigation in 2D NMR relates to the minimum number of scans required for acquiring this kind of spectra, particularly when these are dictated by sampling rather than by sensitivity considerations. Reductions in this minimum number of scans have been achieved by departing from the regular sampling used to monitor the indirect domain, and relying instead on non-uniform sampling and iterative reconstruction algorithms. Alternatively, so-called "ultrafast" methods can compress the minimum number of scans involved in 2D NMR all the way to a minimum number of one, by spatially encoding the indirect domain information and subsequently recovering it via oscillating field gradients. Given ultrafast NMR's simultaneous recording of the indirect- and direct-domain data, this experiment couples the spectral constraints of these orthogonal domains - often calling for the use of strong acquisition gradients and large filter widths to fulfill the desired bandwidth and resolution demands along all spectral dimensions. This study discusses a way to alleviate these demands, and thereby enhance the method's performance and applicability, by combining spatial encoding with iterative reconstruction approaches. Examples of these new principles are given based on the compressed-sensed reconstruction of biomolecular 2D HSQC ultrafast NMR data, an approach that we show enables a decrease of the gradient strengths demanded in this type of experiments by up to 80%. Copyright © 2011 Elsevier Inc. All rights reserved.
Optimization of solar cell contacts by system cost-per-watt minimization
NASA Technical Reports Server (NTRS)
Redfield, D.
1977-01-01
New, and considerably altered, optimum dimensions for solar-cell metallization patterns are found using the recently developed procedure whose optimization criterion is the minimum cost-per-watt effect on the entire photovoltaic system. It is also found that the optimum shadow fraction by the fine grid is independent of metal cost and resistivity as well as cell size. The optimum thickness of the fine grid metal depends on all these factors, and in familiar cases it should be appreciably greater than that found by less complete analyses. The optimum bus bar thickness is much greater than those generally used. The cost-per-watt penalty due to the need for increased amounts of metal per unit area on larger cells is determined quantitatively and thereby provides a criterion for the minimum benefits that must be obtained in other process steps to make larger cells cost effective.
Benavides, Fernando G; Merino-Salazar, Pamela; Cornelio, Cecilia; Assunção, Ada Avila; Agudelo-Suárez, Andrés A; Amable, Marcelo; Artazcoz, Lucía; Astete, Jonh; Barraza, Douglas; Berhó, Fabián; Milián, Lino Carmenate; Delclòs, George; Funcasta, Lorena; Gerke, Johanna; Gimeno, David; Itatí-Iñiguez, María José; Lima, Eduardo de Paula; Martínez-Iñigo, David; Medeiros, Adriane Mesquita de; Orta, Lida; Pinilla, Javier; Rodrigo, Fernando; Rojas, Marianela; Sabastizagal, Iselle; Vallebuona, Clelia; Vermeylen, Greet; Villalobos, Gloria H; Vives, Alejandra
2016-10-10
This article aimed to present a basic questionnaire and minimum methodological criteria for consideration in future Surveys on Working Conditions, Employment, and Health in Latin America and the Caribbean. A virtual and face-to-face consensus process was conducted with participation by a group of international experts who used the surveys available up until 2013 as the point of departure for defining the proposal. The final questionnaire included 77 questions grouped in six dimensions: socio-demographic characteristics of workers and companies; employment conditions; working conditions; health status; resources and preventive activities; and family characteristics. The minimum methodological criteria feature the interviewee's home as the place for the interview and aspects related to the quality of the fieldwork. These results can help improve the comparability of future surveys in Latin America and the Caribbean, which would in turn help improve information on workers' heath in the region.
Design of landfill daily cells.
Panagiotakopoulos, D; Dokas, I
2001-08-01
The objective of this paper is to study the behaviour of the landfill soil-to-refuse (S/R) ratio when size, geometry and operating parameters of the daily cell vary over realistic ranges. A simple procedure is presented (1) for calculating the cell parameters values which minimise the S/R ratio and (2) for studying the sensitivity of this minimum S/R ratio to variations in cell size, final refuse density, working face length, lift height and cover thickness. In countries where daily soil cover is required, savings in landfill space could be realised following this procedure. The sensitivity of minimum S/R to variations in cell dimensions decreases with cell size. Working face length and lift height affect the S/R ratio significantly. This procedure also offers the engineer an additional tool for comparing one large daily cell with two or more smaller ones, at two different working faces within the same landfill.
Four-Dimensional Golden Search
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fenimore, Edward E.
2015-02-25
The Golden search technique is a method to search a multiple-dimension space to find the minimum. It basically subdivides the possible ranges of parameters until it brackets, to within an arbitrarily small distance, the minimum. It has the advantages that (1) the function to be minimized can be non-linear, (2) it does not require derivatives of the function, (3) the convergence criterion does not depend on the magnitude of the function. Thus, if the function is a goodness of fit parameter such as chi-square, the convergence does not depend on the noise being correctly estimated or the function correctly followingmore » the chi-square statistic. And, (4) the convergence criterion does not depend on the shape of the function. Thus, long shallow surfaces can be searched without the problem of premature convergence. As with many methods, the Golden search technique can be confused by surfaces with multiple minima.« less
STS mission duration enhancement study: (orbiter habitability)
NASA Technical Reports Server (NTRS)
Carlson, A. D.
1979-01-01
Habitability improvements for early flights that could be implemented with minimum impact were investigated. These included: (1) launching the water dispenser in the on-orbit position instead of in a locker; (2) the sleep pallet concept; and (3) suction cup foot restraints. Past studies that used volumetric terms and requirements for crew size versus mission duration were reviewed and common definitions of key habitability terms were established. An accurately dimensioned drawing of the orbiter mid-deck, locating all of the known major elements was developed. Finally, it was established that orbiter duration and crew size can be increased with minimum modification and impact to the crew module. Preliminary concepts of the aft med-deck, external versions of expanded tunnel adapters (ETA), and interior concepts of ETA-3 were developed and comparison charts showing the various factors of volume, weight, duration, size, impact to orbiter, and number of sleep stations were generated.
NASA Astrophysics Data System (ADS)
Allafchian, Ali R.; Jalali, S. A. H.; Amiri, R.; Shahabadi, Sh.
2016-11-01
In this study, the NiFe2O4 was embedded in (3-mercaptopropyl) trimethoxysilane (TPS) and tetraethyl orthosilicate (TEOS) using the sol-gel method. These compounds were used as the support of Ag nanoparticles (Ag NPs). The NiFe2O4@TEOS-TPS@Ag nanocomposites were obtained with the development of bonding between the silver atoms of Ag NPs and the sulfur atoms of TPS molecule. Field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used for the characterization of the Ag nanocomposites. Also, the magnetic properties of these nanocomposites were studied by using a vibrating sample magnetometer (VSM) technique. The disk diffusion, minimum inhibition concentration (MIC) and minimum bactericidal concentrations (MBC) tests were used for the investigation of the antibacterial effect of this nanocomposite against bacterial strains. The synthesized nanocomposite presented high reusability and good antibacterial activity against gram-positive and gram-negative bacteria. Remarkably, this nanocomposite could be easily removed from the disinfected media by magnetic decantation.
Feasibility study of a TIMEPIX detector for mammography applications
NASA Astrophysics Data System (ADS)
Ávila, Carlos A.; Mendoza, Luis M.; Roque, Gerardo A.; Loaiza, Leonardo; Racedo, Jorge; Rueda, Roberto
2017-11-01
We present a comparison study of two X-ray systems for mammography imaging. One is a SELENIA clinical system and the second is a TIMEPIX based system. The aim of the study is to determine the capability of a TIMEPIX detector for mammography applications. We first compare signal to noise ratio (SNR) of X-ray images of Al2O3 spheres with diameters of 0.16mm, 0.24mm and 0.32mm, of a commercial mammography accreditation phantom CIRS015, obtained with each system. Then, we make a similar comparison for a second phantom built with Hydroxyapatite crystals with different morphology and sizes ranging between 0.15mm and 0.83mm, which are embedded within the same block of PMMA of the CIRS015 phantom. Our study allows us to determine the minimum size of Al2O3 spheres on the order of 240μm, with 33% lower SNR for the TIMEPIX system as compared to the SELENIA system. When comparing the images of Hydroxyapatite crystals from both systems, the minimum size observed is about 300μm, with 23% lower SNR for TIMEPIX.
Geological Carbon Sequestration: A New Approach for Near-Surface Assurance Monitoring
Wielopolski, Lucian
2011-01-01
There are two distinct objectives in monitoring geological carbon sequestration (GCS): Deep monitoring of the reservoir’s integrity and plume movement and near-surface monitoring (NSM) to ensure public health and the safety of the environment. However, the minimum detection limits of the current instrumentation for NSM is too high for detecting weak signals that are embedded in the background levels of the natural variations, and the data obtained represents point measurements in space and time. A new approach for NSM, based on gamma-ray spectroscopy induced by inelastic neutron scatterings (INS), offers novel and unique characteristics providing the following: (1) High sensitivity with a reducible error of measurement and detection limits, and, (2) temporal- and spatial-integration of carbon in soil that results from underground CO2 seepage. Preliminary field results validated this approach showing carbon suppression of 14% in the first year and 7% in the second year. In addition the temporal behavior of the error propagation is presented and it is shown that for a signal at the level of the minimum detection level the error asymptotically approaches 47%. PMID:21556180
a Fractal Permeability Model Coupling Boundary-Layer Effect for Tight Oil Reservoirs
NASA Astrophysics Data System (ADS)
Wang, Fuyong; Liu, Zhichao; Jiao, Liang; Wang, Congle; Guo, Hu
A fractal permeability model coupling non-flowing boundary-layer effect for tight oil reservoirs was proposed. Firstly, pore structures of tight formations were characterized with fractal theory. Then, with the empirical equation of boundary-layer thickness, Hagen-Poiseuille equation and fractal theory, a fractal torturous capillary tube model coupled with boundary-layer effect was developed, and verified with experimental data. Finally, the parameters influencing effective liquid permeability were quantitatively investigated. The research results show that effective liquid permeability of tight formations is not only decided by pore structures, but also affected by boundary-layer distributions, and effective liquid permeability is the function of fluid type, fluid viscosity, pressure gradient, fractal dimension, tortuosity fractal dimension, minimum pore radius and maximum pore radius. For the tight formations dominated with nanoscale pores, boundary-layer effect can significantly reduce effective liquid permeability, especially under low pressure gradient.
Instability of black strings in the third-order Lovelock theory
NASA Astrophysics Data System (ADS)
Giacomini, Alex; Henríquez-Báez, Carla; Lagos, Marcela; Oliva, Julio; Vera, Aldo
2016-05-01
We show that homogeneous black strings of third-order Lovelock theory are unstable under s-wave perturbations. This analysis is done in dimension D =9 , which is the lowest dimension that allows the existence of homogeneous black strings in a theory that contains only the third-order Lovelock term in the Lagrangian. As is the case in general relativity, the instability is produced by long wavelength perturbations and it stands for the perturbative counterpart of a thermal instability. We also provide a comparative analysis of the instabilities of black strings at a fixed radius in general relativity, Gauss-Bonnet, and third-order Lovelock theories. We show that the minimum critical wavelength that triggers the instability grows with the power of the curvature defined in the Lagrangian. The maximum exponential growth during the time of the perturbation is the largest in general relativity and it decreases with the number of curvatures involved in the Lagrangian.
On the partition dimension of comb product of path and complete graph
NASA Astrophysics Data System (ADS)
Darmaji, Alfarisi, Ridho
2017-08-01
For a vertex v of a connected graph G(V, E) with vertex set V(G), edge set E(G) and S ⊆ V(G). Given an ordered partition Π = {S1, S2, S3, …, Sk} of the vertex set V of G, the representation of a vertex v ∈ V with respect to Π is the vector r(v|Π) = (d(v, S1), d(v, S2), …, d(v, Sk)), where d(v, Sk) represents the distance between the vertex v and the set Sk and d(v, Sk) = min{d(v, x)|x ∈ Sk}. A partition Π of V(G) is a resolving partition if different vertices of G have distinct representations, i.e., for every pair of vertices u, v ∈ V(G), r(u|Π) ≠ r(v|Π). The minimum k of Π resolving partition is a partition dimension of G, denoted by pd(G). Finding the partition dimension of G is classified to be a NP-Hard problem. In this paper, we will show that the partition dimension of comb product of path and complete graph. The results show that comb product of complete grapph Km and path Pn namely p d (Km⊳Pn)=m where m ≥ 3 and n ≥ 2 and p d (Pn⊳Km)=m where m ≥ 3, n ≥ 2 and m ≥ n.
Fractal dimension and the navigational information provided by natural scenes.
Shamsyeh Zahedi, Moosarreza; Zeil, Jochen
2018-01-01
Recent work on virtual reality navigation in humans has suggested that navigational success is inversely correlated with the fractal dimension (FD) of artificial scenes. Here we investigate the generality of this claim by analysing the relationship between the fractal dimension of natural insect navigation environments and a quantitative measure of the navigational information content of natural scenes. We show that the fractal dimension of natural scenes is in general inversely proportional to the information they provide to navigating agents on heading direction as measured by the rotational image difference function (rotIDF). The rotIDF determines the precision and accuracy with which the orientation of a reference image can be recovered or maintained and the range over which a gradient descent in image differences will find the minimum of the rotIDF, that is the reference orientation. However, scenes with similar fractal dimension can differ significantly in the depth of the rotIDF, because FD does not discriminate between the orientations of edges, while the rotIDF is mainly affected by edge orientation parallel to the axis of rotation. We present a new equation for the rotIDF relating navigational information to quantifiable image properties such as contrast to show (1) that for any given scene the maximum value of the rotIDF (its depth) is proportional to pixel variance and (2) that FD is inversely proportional to pixel variance. This contrast dependence, together with scene differences in orientation statistics, explains why there is no strict relationship between FD and navigational information. Our experimental data and their numerical analysis corroborate these results.
Alamanou, G Despoina; Balokas, A Sotirios; Fotos, V Nikolaos; Patiraki, Elisabeth; Brokalaki, Hero
2016-02-01
The aim of this study was to validate the translated in Greek Cassileth's Information Styles Questionnaire (ISQ). It was a cross-sectional study. The sample consisted of one hundred and nine adult patients diagnosed with cancer, attending the oncology outpatient department (outpatients) or being hospitalized (inpatients), from January 2013 to September 2013, in one general hospital in Athens. Two instruments were used: The Control Preference Scale (CPS), an assessment tool to measure decision-making preferences of cancer patients and ISQ to assess the information needs of patients. Exploratory factor analysis (EFA) was carried out to evaluate construct validity of the ISQ. The internal consistency of subscales was analyzed with Cronbach's alpha and the association of demographics and clinical variables with the ISQ was explored using linear regression analysis. Sixty one (56%) patients were males. The mean age was 65.5 (SD = 11.9) years. Two dimensions of the ISQ were revealed. Cronbach's alpha was 0.92 for "Disease and treatment" dimension (12 of 17 items of the questionnaire) and 0.89 for "Psychological" dimension (5 of 17 items of the questionnaire). Statistical analysis showed that the patients' preferred decision making roles were associated with the ISQ dimensions. Also, age, sex, diagnosis, educational level and the existence of metastasis were associated with the score of "Disease and treatment" dimension. All the scales of ISQ, exceeded the minimum reliability standard of 0.70. The results showed that the Greek ISQ is a reliable and valid tool for identifying the information needs of cancer patients. Copyright © 2015 Elsevier Ltd. All rights reserved.
Expedite random structure searching using objects from Wyckoff positions
NASA Astrophysics Data System (ADS)
Wang, Shu-Wei; Hsing, Cheng-Rong; Wei, Ching-Ming
2018-02-01
Random structure searching has been proved to be a powerful approach to search and find the global minimum and the metastable structures. A true random sampling is in principle needed yet it would be highly time-consuming and/or practically impossible to find the global minimum for the complicated systems in their high-dimensional configuration space. Thus the implementations of reasonable constraints, such as adopting system symmetries to reduce the independent dimension in structural space and/or imposing chemical information to reach and relax into low-energy regions, are the most essential issues in the approach. In this paper, we propose the concept of "object" which is either an atom or composed of a set of atoms (such as molecules or carbonates) carrying a symmetry defined by one of the Wyckoff positions of space group and through this process it allows the searching of global minimum for a complicated system to be confined in a greatly reduced structural space and becomes accessible in practice. We examined several representative materials, including Cd3As2 crystal, solid methanol, high-pressure carbonates (FeCO3), and Si(111)-7 × 7 reconstructed surface, to demonstrate the power and the advantages of using "object" concept in random structure searching.
Effects of sterile neutrinos and an extra dimension on big bang nucleosynthesis
NASA Astrophysics Data System (ADS)
Jang, Dukjae; Kusakabe, Motohiko; Cheoun, Myung-Ki
2018-02-01
By assuming the existence of extra-dimensional sterile neutrinos in the big bang nucleosynthesis (BBN) epoch, we investigate the sterile neutrino (νs) effects on the BBN and constrain some parameters associated with the νs properties. First, for the cosmic expansion rate, we take into account effects of a five-dimensional bulk and intrinsic tension of the brane embedded in the bulk and constrain a key parameter of the extra dimension by using the observational element abundances. Second, effects of the νs traveling on or off the brane are considered. In this model, the effective mixing angle between a νs and an active neutrino depends on energy, which may give rise to a resonance effect on the mixing angle. Consequently, the reaction rate of the νs can be drastically changed during the cosmic evolution. We estimated abundances and temperature of the νs by solving the rate equation as a function of temperature until the sterile neutrino decoupling. We then find that the relic abundance of the νs is drastically enhanced by the extra dimension and maximized for a characteristic resonance energy Eres≳0.01 GeV . Finally, some constraints related to the νs, i.e., mixing angle and mass difference, are discussed in detail with the comparison of our BBN calculations corrected by the extra-dimensional νs to observational data on light element abundances.
More N =4 superconformal bootstrap
NASA Astrophysics Data System (ADS)
Beem, Christopher; Rastelli, Leonardo; van Rees, Balt C.
2017-08-01
In this long overdue second installment, we continue to develop the conformal bootstrap program for N =4 superconformal field theories (SCFTs) in four dimensions via an analysis of the correlation function of four stress-tensor supermultiplets. We review analytic results for this correlator and make contact with the SCFT/chiral algebra correspondence of Beem et al. [Commun. Math. Phys. 336, 1359 (2015), 10.1007/s00220-014-2272-x]. We demonstrate that the constraints of unitarity and crossing symmetry require the central charge c to be greater than or equal to 3 /4 in any interacting N =4 SCFT. We apply numerical bootstrap methods to derive upper bounds on scaling dimensions and operator product expansion coefficients for several low-lying, unprotected operators as a function of the central charge. We interpret our bounds in the context of N =4 super Yang-Mills theories, formulating a series of conjectures regarding the embedding of the conformal manifold—parametrized by the complexified gauge coupling—into the space of scaling dimensions and operator product expansion coefficients. Our conjectures assign a distinguished role to points on the conformal manifold that are self-dual under a subgroup of the S -duality group. This paper contains a more detailed exposition of a number of results previously reported in Beem et al. [Phys. Rev. Lett. 111, 071601 (2013), 10.1103/PhysRevLett.111.071601] in addition to new results.
Fischer, Mark W. F.; Stolze-Rybczynski, Jessica L.; Cui, Yunluan; Money, Nicholas P.
2010-01-01
Active discharge of basidiospores in most species of Basidiomycota is powered by the rapid movement of a droplet of fluid, called Buller’s drop, over the spore surface. This paper is concerned with the operation of the launch mechanism in species with the largest and smallest ballistospores. Aleurodiscus gigasporus (Russulales) produces the largest basidiospores on record. The maximum dimensions of the spores, 34 × 28 µm, correspond to a volume of 14 pL and to an estimated mass of 17 ng. The smallest recorded basidiospores are produced by Hyphodontia latitans (Hymenochaetales). Minimum spore dimensions in this species, 3.5 × 0.5 µm, correspond to a volume of 0.5 fL and mass of 0.6 pg. Neither species has been studied using high-speed video microscopy, but this technique was used to examine ballistospore discharge in species with spores of similar sizes (slightly smaller than A. gigasporus and slightly larger than those of H. latitans). Extrapolation of velocity measurements from these fungi provided estimates of discharge distances ranging from a maximum of almost 2 mm in A. gigasporus to a minimum of 4 µm in H. latitans. These are, respectively, the longest and shortest predicted discharge distances for ballistospores. Limitations to the distances traveled by basidiospores are discussed in relation to the mechanics of the discharge process and the types of fruit-bodies from which the spores are released. PMID:20835365
Nasal airway changes in bone-borne and tooth-borne rapid maxillary expansion treatments.
Kabalan, Ousama; Gordon, Jillian; Heo, Giseon; Lagravère, Manuel O
2015-03-01
Our aim was to determine the presence of a correlation between the nasal airway skeletal transverse dimension and air intake changes in rapid maxillary expansion treatments. Sixty-one patients with maxillary transverse deficiency (11-17 years old) were randomly allocated into three groups (two treatment groups - tooth- [hyrax] or bone-borne [miniscrew-implant-based] expander - and one control group). Cone-beam computed tomography scans (CBCT) were obtained from each patient as well as acoustic rhinometry (AR) readings. Specifically, in AR, airway volume up to minimum cross-sectional areas (Vol. 1&2) and minimum cross-sectional areas (Min. 1&2) in the nasal cavity were measured. Records were obtained at two time points (initial T1 and at removal of appliance at 6 months T2). CBCTs were analyzed using AVIZO software and landmarks were placed on the nasal base. Descriptive statistics were compiled and student's t-test was used. Of the 480 pairings measured, only 9 showed statistically significant positive correlations between T1 and T2. Correlation data were highly variable in all categories, showing no clear tendencies. No statistical difference was found when comparing all groups in terms of airway changes. With very few positive correlations observed and otherwise highly variable data, no really conclusive finding was obtained to suggest any realistic correlation between changes in the skeletal dimensions and changes in the nasal airway. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Dimension reduction and multiscaling law through source extraction
NASA Astrophysics Data System (ADS)
Capobianco, Enrico
2003-04-01
Through the empirical analysis of financial return generating processes one may find features that are common to other research fields, such as internet data from network traffic, physiological studies about human heart beat, speech and sleep recorded time series, geophysics signals, just to mention well-known cases of study. In particular, long range dependence, intermittency, heteroscedasticity are clearly appearing, and consequently power laws and multi-scaling behavior result typical signatures of either the spectral or the time correlation diagnostics. We study these features and the dynamics underlying financial volatility, which can respectively be detected and inferred from high frequency realizations of stock index returns, and show that they vary according to the resolution levels used for both the analysis and the synthesis of the available information. Discovering whether the volatility dynamics are subject to changes in scaling regimes requires the consideration of a model embedding scale-dependent information packets, thus accounting for possible heterogeneous activity occurring in financial markets. Independent component analysis result to be an important tool for reducing the dimension of the problem and calibrating greedy approximation techniques aimed to learn the structure of the underlying volatility.
Detection of seizures from small samples using nonlinear dynamic system theory.
Yaylali, I; Koçak, H; Jayakar, P
1996-07-01
The electroencephalogram (EEG), like many other biological phenomena, is quite likely governed by nonlinear dynamics. Certain characteristics of the underlying dynamics have recently been quantified by computing the correlation dimensions (D2) of EEG time series data. In this paper, D2 of the unbiased autocovariance function of the scalp EEG data was used to detect electrographic seizure activity. Digital EEG data were acquired at a sampling rate of 200 Hz per channel and organized in continuous frames (duration 2.56 s, 512 data points). To increase the reliability of D2 computations with short duration data, raw EEG data were initially simplified using unbiased autocovariance analysis to highlight the periodic activity that is present during seizures. The D2 computation was then performed from the unbiased autocovariance function of each channel using the Grassberger-Procaccia method with Theiler's box-assisted correlation algorithm. Even with short duration data, this preprocessing proved to be computationally robust and displayed no significant sensitivity to implementation details such as the choices of embedding dimension and box size. The system successfully identified various types of seizures in clinical studies.
Girls in detail, boys in shape: gender differences when drawing cubes in depth.
Lange-Küttner, C; Ebersbach, M
2013-08-01
The current study tested gender differences in the developmental transition from drawing cubes in two- versus three dimensions (3D), and investigated the underlying spatial abilities. Six- to nine-year-old children (N = 97) drew two occluding model cubes and solved several other spatial tasks. Girls more often unfolded the various sides of the cubes into a layout, also called diagrammatic cube drawing (object design detail). In girls, the best predictor for drawing the cubes was Mental Rotation Test (MRT) accuracy. In contrast, boys were more likely to preserve the optical appearance of the cube array. Their drawing in 3D was best predicted by MRT reaction time and the Embedded Figures Test (EFT). This confirmed boys' stronger focus on the contours of an object silhouette (object shape). It is discussed whether the two gender-specific approaches to drawing in three dimensions reflect two sides of the appearance-reality distinction in drawing, that is graphic syntax of object design features versus visual perception of projective space. © 2012 The British Psychological Society.
Taub-NUT Spacetime in the (A)dS/CFT and M-Theory [electronic resource
NASA Astrophysics Data System (ADS)
Clarkson, Richard
In the following thesis, I will conduct a thermodynamic analysis of the Taub-NUT spacetime in various dimensions, as well as show uses for Taub-NUT and other Hyper-Kahler spacetimes. Thermodynamic analysis (by which I mean the calculation of the entropy and other thermodynamic quantities, and the analysis of these quantities) has in the past been done by use of background subtraction. The recent derivation of the (A)dS/CFT correspondences from String theory has allowed for easier and quicker analysis. I will use Taub-NUT space as a template to test these correspondences against the standard thermodynamic calculations (via the N?ether method), with (in the Taub-NUT-dS case especially) some very interesting results. There is also interest in obtaining metrics in eleven dimensions that can be reduced down to ten dimensional string theory metrics. Taub-NUT and other Hyper-Kahler metrics already possess the form to easily facilitate the Kaluza-Klein reduction, and embedding such metricsinto eleven dimensional metrics containing M2 or M5 branes produces metrics with interesting Dp-brane results.
Dimensions of Phenomenology in Exploring Patient’s Suffering in Long-Life Illnesses
Al Kalaldeh, Mahmoud; Shosha, Ghada Abu; Saiah, Najah; Salameh, Omar
2017-01-01
Background: Patients’ suffering has been increasingly investigated by health-care researchers especially in the chronically ill. Suffering is viewed as a progressive negative consequence that associated with pain, impaired self-esteem, and social alienation. This qualitative evidence synthesis aimed to provide further insights into the application of phenomenology in explaining suffering among patients with chronic illnesses. Methods: Studies included in this qualitative evidence synthesis study were retrieved by searching from the following electronic databases: CINAHL, PubMed Central, and EBSCO. Findings: Phenomenology is regarded as influential to generate in-depth evidence about suffering that are grounded in chronically ill patients’ perspectives. The philosophical constructs of suffering suggested fundamental dimensions such as stress, distress, hopelessness, and depression along with pain. Evidence encompasses the entire manifestation of suffering in which all interrelated meanings are understood and referred to a unique structure. Hermeneutic phenomenology was adopted as an effective strategy to elucidate human experience leading to the discovery of the embedded meanings of life experience. Conclusion: The phenomenological approach provides nursing research with the pathway to explore patients’ suffering experiences in the chronically ill. PMID:29582010
Ultrafast Bessel beams: advanced tools for laser materials processing
NASA Astrophysics Data System (ADS)
Stoian, Razvan; Bhuyan, Manoj K.; Zhang, Guodong; Cheng, Guanghua; Meyer, Remy; Courvoisier, Francois
2018-05-01
Ultrafast Bessel beams demonstrate a significant capacity of structuring transparent materials with a high degree of accuracy and exceptional aspect ratio. The ability to localize energy on the nanometer scale (bypassing the 100-nm milestone) makes them ideal tools for advanced laser nanoscale processing on surfaces and in the bulk. This allows to generate and combine micron and nano-sized features into hybrid structures that show novel functionalities. Their high aspect ratio and the accurate location can equally drive an efficient material modification and processing strategy on large dimensions. We review, here, the main concepts of generating and using Bessel non-diffractive beams and their remarkable features, discuss general characteristics of their interaction with matter in ablation and material modification regimes, and advocate their use for obtaining hybrid micro and nanoscale structures in two and three dimensions (2D and 3D) performing complex functions. High-throughput applications are indicated. The example list ranges from surface nanostructuring and laser cutting to ultrafast laser welding and the fabrication of 3D photonic systems embedded in the volume.
The partition dimension of subdivision of a graph
NASA Astrophysics Data System (ADS)
Amrullah, Baskoro, Edy Tri; Uttunggadewa, Saladin; Simanjuntak, Rinovia
2016-02-01
Let G = (V,E) be a connected graph, u,v ∈ V (G), e = uv ∈ E(G) and k be a positive integer. A k-subdivision of an edge e is a replacement of e = uv with a path u, x1, x2, x ..., xk, v. A graph G with a k-subdivided edge is denoted with S(G(e; k)). Let p be a positive integer and Π = {L1, L2, L3, …, Lp} be a p-partition of V (G). The representation of a vertex v with respect to Π, r(v|Π), is the vector (d(v, L1), d(v, L2), d(v, L3),…, d(v, Lp)) where d(v, Li) for i ∈ [1, p] is the minimum distance between v and the vertices of Li. The partition Π is called a resolving partition of G if r(w|Π) ≠ r(v|Π) for all w ≠ v ∈ V (G). The partition dimension, pd(G), of G is the smallest integer p such that G has a resolving p-partition. In this paper, we present sharp upper and lower bounds of the partition dimension of S(G(e; k)) for any graph G.
Friedmann, Simon; Frémaux, Nicolas; Schemmel, Johannes; Gerstner, Wulfram; Meier, Karlheinz
2013-01-01
In this study, we propose and analyze in simulations a new, highly flexible method of implementing synaptic plasticity in a wafer-scale, accelerated neuromorphic hardware system. The study focuses on globally modulated STDP, as a special use-case of this method. Flexibility is achieved by embedding a general-purpose processor dedicated to plasticity into the wafer. To evaluate the suitability of the proposed system, we use a reward modulated STDP rule in a spike train learning task. A single layer of neurons is trained to fire at specific points in time with only the reward as feedback. This model is simulated to measure its performance, i.e., the increase in received reward after learning. Using this performance as baseline, we then simulate the model with various constraints imposed by the proposed implementation and compare the performance. The simulated constraints include discretized synaptic weights, a restricted interface between analog synapses and embedded processor, and mismatch of analog circuits. We find that probabilistic updates can increase the performance of low-resolution weights, a simple interface between analog synapses and processor is sufficient for learning, and performance is insensitive to mismatch. Further, we consider communication latency between wafer and the conventional control computer system that is simulating the environment. This latency increases the delay, with which the reward is sent to the embedded processor. Because of the time continuous operation of the analog synapses, delay can cause a deviation of the updates as compared to the not delayed situation. We find that for highly accelerated systems latency has to be kept to a minimum. This study demonstrates the suitability of the proposed implementation to emulate the selected reward modulated STDP learning rule. It is therefore an ideal candidate for implementation in an upgraded version of the wafer-scale system developed within the BrainScaleS project.
Friedmann, Simon; Frémaux, Nicolas; Schemmel, Johannes; Gerstner, Wulfram; Meier, Karlheinz
2013-01-01
In this study, we propose and analyze in simulations a new, highly flexible method of implementing synaptic plasticity in a wafer-scale, accelerated neuromorphic hardware system. The study focuses on globally modulated STDP, as a special use-case of this method. Flexibility is achieved by embedding a general-purpose processor dedicated to plasticity into the wafer. To evaluate the suitability of the proposed system, we use a reward modulated STDP rule in a spike train learning task. A single layer of neurons is trained to fire at specific points in time with only the reward as feedback. This model is simulated to measure its performance, i.e., the increase in received reward after learning. Using this performance as baseline, we then simulate the model with various constraints imposed by the proposed implementation and compare the performance. The simulated constraints include discretized synaptic weights, a restricted interface between analog synapses and embedded processor, and mismatch of analog circuits. We find that probabilistic updates can increase the performance of low-resolution weights, a simple interface between analog synapses and processor is sufficient for learning, and performance is insensitive to mismatch. Further, we consider communication latency between wafer and the conventional control computer system that is simulating the environment. This latency increases the delay, with which the reward is sent to the embedded processor. Because of the time continuous operation of the analog synapses, delay can cause a deviation of the updates as compared to the not delayed situation. We find that for highly accelerated systems latency has to be kept to a minimum. This study demonstrates the suitability of the proposed implementation to emulate the selected reward modulated STDP learning rule. It is therefore an ideal candidate for implementation in an upgraded version of the wafer-scale system developed within the BrainScaleS project. PMID:24065877
NASA Astrophysics Data System (ADS)
Dalouji, Vali; Asareh, Nastaran; Hashemizadeh, Seyed Ali; Solaymani, Shahram
2016-12-01
In this paper, the electrical conductivity of carbon films embedded by nickel nanoparticles at different deposition times 50, 90, 180 and 600 s over a temperature range from 50 to 500 K was studied. The conductivity data in the temperature range T > 300 K shows the extended state conduction mechanism. The tunneling through a thermally vibrating barrier in the temperature range 50-150 K is described by the Berthelot-type conduction mechanism. It can be seen that the films deposited at 180 s have maximum conductivity and the Berthelot temperature is about 53.5 K. Due to the vibrations of Ni ions in the tetrahedral, sites the extents of the carrier wave function are lower than in the octahedral complexes sites which have maximum values of about 2.16 × 10^{-7} cm and 1.85 × 10^{-7} cm in the octahedral-metal stretching vibrations and intrinsic stretching vibrations of the metal ions at the tetrahedral site, respectively. On the other hand, the average distance between the sites in both vibrations at 180 s deposition modes have minimum values of 2.02 × 10^{-7} cm and 1.72 × 10^{-7} cm.
A SIMPLE TUMBLING DEVICE USED IN PREPARING ALGAL SPECIMENS FOR ELECTRON MICROSCOPY.
Berlagnolli, B L; Nadakavukaren, M J
1969-06-01
Screw cap vials are held in a wooden holder which rotates at a 90° angle to the horizontal. The. shaft of a small electric motor with built-in gear box is attached perpendicularly to the wooden vial holder via a hole drilled in the center of the wooden holder. The rotation of the vial holder is about 6 rpm. This motion ensures a thorough tumbling of the contents of the vials. Even viscous embedding media are kept in constant agitation, which provides for superior penetration of the tissue. Tumbling devices to hold a range of vial sizes can be constructed with a minimum of labor at a cost of $10-20 each.
General-Purpose Front End for Real-Time Data Processing
NASA Technical Reports Server (NTRS)
James, Mark
2007-01-01
FRONTIER is a computer program that functions as a front end for any of a variety of other software of both the artificial intelligence (AI) and conventional data-processing types. As used here, front end signifies interface software needed for acquiring and preprocessing data and making the data available for analysis by the other software. FRONTIER is reusable in that it can be rapidly tailored to any such other software with minimum effort. Each component of FRONTIER is programmable and is executed in an embedded virtual machine. Each component can be reconfigured during execution. The virtual-machine implementation making FRONTIER independent of the type of computing hardware on which it is executed.
NASA Technical Reports Server (NTRS)
Ponchak, George E.; Amadjikpe, Arnaud L.; Choudhury, Debabani; Papapolymerou, John
2011-01-01
In this paper, the first measurements of the received radiated power between antennas located on a conference table to simulate the environment of antennas embedded in laptop computers for 60 GHz Wireless Personal Area Network (WPAN) applications is presented. A high gain horn antenna and a medium gain microstrip patch antenna for two linear polarizations are compared. It is shown that for a typical conference table arrangement with five computers, books, pens, and coffee cups, the antennas should be placed a minimum of 5 cm above the table, but that a height of greater than 20 cm may be required to maximize the received power in all cases.
Porta, Alberto; Faes, Luca; Bari, Vlasta; Marchi, Andrea; Bassani, Tito; Nollo, Giandomenico; Perseguini, Natália Maria; Milan, Juliana; Minatel, Vinícius; Borghi-Silva, Audrey; Takahashi, Anielle C. M.; Catai, Aparecida M.
2014-01-01
The proposed approach evaluates complexity of the cardiovascular control and causality among cardiovascular regulatory mechanisms from spontaneous variability of heart period (HP), systolic arterial pressure (SAP) and respiration (RESP). It relies on construction of a multivariate embedding space, optimization of the embedding dimension and a procedure allowing the selection of the components most suitable to form the multivariate embedding space. Moreover, it allows the comparison between linear model-based (MB) and nonlinear model-free (MF) techniques and between MF approaches exploiting local predictability (LP) and conditional entropy (CE). The framework was applied to study age-related modifications of complexity and causality in healthy humans in supine resting (REST) and during standing (STAND). We found that: 1) MF approaches are more efficient than the MB method when nonlinear components are present, while the reverse situation holds in presence of high dimensional embedding spaces; 2) the CE method is the least powerful in detecting age-related trends; 3) the association of HP complexity on age suggests an impairment of cardiac regulation and response to STAND; 4) the relation of SAP complexity on age indicates a gradual increase of sympathetic activity and a reduced responsiveness of vasomotor control to STAND; 5) the association from SAP to HP on age during STAND reveals a progressive inefficiency of baroreflex; 6) the reduced connection from HP to SAP with age might be linked to the progressive exploitation of Frank-Starling mechanism at REST and to the progressive increase of peripheral resistances during STAND; 7) at REST the diminished association from RESP to HP with age suggests a vagal withdrawal and a gradual uncoupling between respiratory activity and heart; 8) the weakened connection from RESP to SAP with age might be related to the progressive increase of left ventricular thickness and vascular stiffness and to the gradual decrease of respiratory sinus arrhythmia. PMID:24586796
Patterns of Twitter Behavior Among Networks of Cannabis Dispensaries in California.
Peiper, Nicholas C; Baumgartner, Peter M; Chew, Robert F; Hsieh, Yuli P; Bieler, Gayle S; Bobashev, Georgiy V; Siege, Christopher; Zarkin, Gary A
2017-07-04
Twitter represents a social media platform through which medical cannabis dispensaries can rapidly promote and advertise a multitude of retail products. Yet, to date, no studies have systematically evaluated Twitter behavior among dispensaries and how these behaviors influence the formation of social networks. This study sought to characterize common cyberbehaviors and shared follower networks among dispensaries operating in two large cannabis markets in California. From a targeted sample of 119 dispensaries in the San Francisco Bay Area and Greater Los Angeles, we collected metadata from the dispensary accounts using the Twitter API. For each city, we characterized the network structure of dispensaries based upon shared followers, then empirically derived communities with the Louvain modularity algorithm. Principal components factor analysis was employed to reduce 12 Twitter measures into a more parsimonious set of cyberbehavioral dimensions. Finally, quadratic discriminant analysis was implemented to verify the ability of the extracted dimensions to classify dispensaries into their derived communities. The modularity algorithm yielded three communities in each city with distinct network structures. The principal components factor analysis reduced the 12 cyberbehaviors into five dimensions that encompassed account age, posting frequency, referencing, hyperlinks, and user engagement among the dispensary accounts. In the quadratic discriminant analysis, the dimensions correctly classified 75% (46/61) of the communities in the San Francisco Bay Area and 71% (41/58) in Greater Los Angeles. The most centralized and strongly connected dispensaries in both cities had newer accounts, higher daily activity, more frequent user engagement, and increased usage of embedded media, keywords, and hyperlinks. Measures derived from both network structure and cyberbehavioral dimensions can serve as key contextual indicators for the online surveillance of cannabis dispensaries and consumer markets over time. ©Nicholas C Peiper, Peter M Baumgartner, Robert F Chew, Yuli P Hsieh, Gayle S Bieler, Georgiy V Bobashev, Christopher Siege, Gary A Zarkin. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 04.07.2017.
Structure-related statistical singularities along protein sequences: a correlation study.
Colafranceschi, Mauro; Colosimo, Alfredo; Zbilut, Joseph P; Uversky, Vladimir N; Giuliani, Alessandro
2005-01-01
A data set composed of 1141 proteins representative of all eukaryotic protein sequences in the Swiss-Prot Protein Knowledge base was coded by seven physicochemical properties of amino acid residues. The resulting numerical profiles were submitted to correlation analysis after the application of a linear (simple mean) and a nonlinear (Recurrence Quantification Analysis, RQA) filter. The main RQA variables, Recurrence and Determinism, were subsequently analyzed by Principal Component Analysis. The RQA descriptors showed that (i) within protein sequences is embedded specific information neither present in the codes nor in the amino acid composition and (ii) the most sensitive code for detecting ordered recurrent (deterministic) patterns of residues in protein sequences is the Miyazawa-Jernigan hydrophobicity scale. The most deterministic proteins in terms of autocorrelation properties of primary structures were found (i) to be involved in protein-protein and protein-DNA interactions and (ii) to display a significantly higher proportion of structural disorder with respect to the average data set. A study of the scaling behavior of the average determinism with the setting parameters of RQA (embedding dimension and radius) allows for the identification of patterns of minimal length (six residues) as possible markers of zones specifically prone to inter- and intramolecular interactions.
Perturbatively deformed defects in Pöschl-Teller-driven scenarios for quantum mechanics
NASA Astrophysics Data System (ADS)
Bernardini, Alex E.; da Rocha, Roldão
2016-07-01
Pöschl-Teller-driven solutions for quantum mechanical fluctuations are triggered off by single scalar field theories obtained through a systematic perturbative procedure for generating deformed defects. The analytical properties concerning the quantum fluctuations in one-dimension, zero-mode states, first- and second-excited states, and energy density profiles are all obtained from deformed topological and non-topological structures supported by real scalar fields. Results are firstly derived from an integrated λϕ4 theory, with corresponding generalizations applied to starting λχ4 and sine-Gordon theories. By focusing our calculations on structures supported by the λϕ4 theory, the outcome of our study suggests an exact quantitative correspondence to Pöschl-Teller-driven systems. Embedded into the perturbative quantum mechanics framework, such a correspondence turns into a helpful tool for computing excited states and continuous mode solutions, as well as their associated energy spectrum, for quantum fluctuations of perturbatively deformed structures. Perturbative deformations create distinct physical scenarios in the context of exactly solvable quantum systems and may also work as an analytical support for describing novel braneworld universes embedded into a 5-dimensional gravity bulk.
Trelease, Robert B; Nieder, Gary L
2013-01-01
Web deployable anatomical simulations or "virtual reality learning objects" can easily be produced with QuickTime VR software, but their use for online and mobile learning is being limited by the declining support for web browser plug-ins for personal computers and unavailability on popular mobile devices like Apple iPad and Android tablets. This article describes complementary methods for creating comparable, multiplatform VR learning objects in the new HTML5 standard format, circumventing platform-specific limitations imposed by the QuickTime VR multimedia file format. Multiple types or "dimensions" of anatomical information can be embedded in such learning objects, supporting different kinds of online learning applications, including interactive atlases, examination questions, and complex, multi-structure presentations. Such HTML5 VR learning objects are usable on new mobile devices that do not support QuickTime VR, as well as on personal computers. Furthermore, HTML5 VR learning objects can be embedded in "ebook" document files, supporting the development of new types of electronic textbooks on mobile devices that are increasingly popular and self-adopted for mobile learning. © 2012 American Association of Anatomists.
Terahertz beam switching by electrical control of graphene-enabled tunable metasurface.
Zhang, Yin; Feng, Yijun; Zhao, Junming; Jiang, Tian; Zhu, Bo
2017-10-26
Controlling the terahertz wave, especially the dynamical and full control of terahertz wavefront, is highly demanded due to the increasing development of practical devices and application systems. Recently considerable efforts have been made to fill the 'terahertz gap' with the help of artificial metamaterial or metasurface incorporated with graphene material. Here, we propose a scheme to design tunable metasurface consisting of metallic patch array on a grounded polymer substrate embedded with graphene layers to electrically control the electromagnetic beam reflection at terahertz frequency. By adjusting geometric dimension of the patch elements, 360 degree reflection phase range may be achieved, thus abrupt phase shifts can be introduced along the metasurface for tailoring the reflected wavefront. Moreover, the reflective phase gradient over the metasurface can be switched between 90 and 360 degree by controlling the Fermi energy of the embedded graphene through voltage biasing, hence dynamically switching the reflective beam directions. Numerical simulations demonstrate that either single beam or dual beam dynamically switching between normal and oblique reflection angles can be well attained at working frequency. The proposed approach will bring much freedom in the design of beam manipulation devices and may be applied to terahertz radiation control.
Sub- and super-diffusion on Cantor sets: Beyond the paradox
NASA Astrophysics Data System (ADS)
K. Golmankhaneh, Alireza; Balankin, Alexander S.
2018-04-01
There is no way to build a nontrivial Markov process having continuous trajectories on a totally disconnected fractal embedded in the Euclidean space. Accordingly, in order to delineate the diffusion process on the totally disconnected fractal, one needs to relax the continuum requirement. Consequently, a diffusion process depends on how the continuum requirement is handled. This explains the emergence of different types of anomalous diffusion on the same totally disconnected set. In this regard, we argue that the number of effective spatial degrees of freedom of a random walker on the totally disconnected Cantor set is equal to nsp = [ D ] + 1, where [ D ] is the integer part of the Hausdorff dimension of the Cantor set. Conversely, the number of effective dynamical degrees of freedom (ds) depends on the definition of a Markov process on the totally disconnected Cantor set embedded in the Euclidean space En (n ≥nsp). This allows us to deduce the equation of diffusion by employing the local differential operators on the Fα-support. The exact solutions of this equation are obtained on the middle-ɛ Cantor sets for different kinds of the Markovian random processes. The relation of our findings to physical phenomena observed in complex systems is highlighted.
NASA Astrophysics Data System (ADS)
Li, Songzhan; Chen, Tian; Wen, Jian; Gui, Pengbin; Fang, Guojia
2017-11-01
Transition metal sulfide nanostructure composites have received significant attention as energy conversion and storage devices. In this work, we report a three-dimension (3D) nanostructure with the Ni9S8 nanorods embedded in oxygen-incorporated MoS2 (O-MoS2) nanosheets for supercapacitors and hydrogen evolution catalysts. The in situ grown Ni9S8/O-MoS2 nanocomposite on carbon cloth can be used as a free binder supercapacitor electrode and hydrogen evolution catalyst. The Ni9S8/O-MoS2 nanocomposite exhibits electrochemical behaviors with a specific capacitance of 907 F g-1 (at 2 A g-1) and good cycle stability after 1200 cycles due to its unique mutual embedding 3D nanostructure. Furthermore, the Ni9S8/O-MoS2 nanocomposite also shows highly electrocatalytic features for hydrogen production with an onset overpotential of ˜150 mV and a low Tafel slope of ˜81 mV dec-1. The oxygen incorporation of MoS2 provides more active sites to participate in the catalytic process for the hydrogen evolution reaction.
Direct Replacement of Arbitrary Grid-Overlapping by Non-Structured Grid
NASA Technical Reports Server (NTRS)
Kao, Kai-Hsiung; Liou, Meng-Sing
1994-01-01
A new approach that uses nonstructured mesh to replace the arbitrarily overlapped structured regions of embedded grids is presented. The present methodology uses the Chimera composite overlapping mesh system so that the physical domain of the flowfield is subdivided into regions which can accommodate easily-generated grid for complex configuration. In addition, a Delaunay triangulation technique generates nonstructured triangular mesh which wraps over the interconnecting region of embedded grids. It is designed that the present approach, termed DRAGON grid, has three important advantages: eliminating some difficulties of the Chimera scheme, such as the orphan points and/or bad quality of interpolation stencils; making grid communication in a fully conservative way; and implementation into three dimensions is straightforward. A computer code based on a time accurate, finite volume, high resolution scheme for solving the compressible Navier-Stokes equations has been further developed to include both the Chimera overset grid and the nonstructured mesh schemes. For steady state problems, the local time stepping accelerates convergence based on a Courant - Friedrichs - Leury (CFL) number near the local stability limit. Numerical tests on representative steady and unsteady supersonic inviscid flows with strong shock waves are demonstrated.
Non-destructive investigation of thermoplastic reinforced composites
Hassen, Ahmed; Taheri, Hossein; Vaidya, Uday
2016-05-09
This paper studies various manufacturing defects in glass fiber/Polypropylene (PP) composite parts and their methods of detection. Foreign Object Inclusion (FOI) of different shapes, sizes, and materials were placed in a glass fiber/PP panel made by compression molding. The paper aims to characterize the fiber orientation and fiber related defects such as fiber waviness in the composite specimen. Comprehensive investigation for different Non Destructive Evaluation (NDE) techniques, namely X-ray radiography and Ultrasonic Testing (UT) techniques to trace and characterize the embedded defects and the composite texture are presented. Conventional X-ray radiography successfully identified the fiber orientation in two dimension (2-D)more » plane; however, information for the sample depth was not captured. The radiography techniques showed low relative errors for the defect size measurements (maximum error was below 9.5%) when compared to the ultrasonic techniques. Ultrasonic techniques were able to map all the embedded artificial defects. Phase Array (PA) ultrasonic technique was able to precisely locate the FOI in the glass fiber/PP specimen. Nerveless, the shape and size of the defects were not accurately determined due to the high signal attenuation and distortion characteristics of the E-glass fiber.« less
Prabhakar, Amit; Mukherji, Soumyo
2010-12-21
In this study, a novel embedded optical waveguide based sensor which utilizes localized surface plasmon resonance of gold nanoparticles coated on a C-shaped polymer waveguide is being reported. The sensor, as designed, can be used as an analysis chip for detection of minor variations in the refractive index of its microenvironment, which makes it suitable for wide scale use as an affinity biosensor. The C-shaped waveguide coupled with microfluidic channel was fabricated by single step patterning of SU8 on an oxidized silicon wafer. The absorbance due to the localized surface plasmon resonance (LSPR) of SU8 waveguide bound gold nano particle (GNP) was found to be linear with refractive index changes between 1.33 and 1.37. A GNP coated C-bent waveguide of 200 μ width with a bend radius of 1 mm gave rise to a sensitivity of ~5 ΔA/RIU at 530 nm as compared to the ~2.5 ΔA/RIU (refractive index units) of the same dimension bare C-bend SU8 waveguide. The resolution of the sensor probe was ~2 × 10(-4) RIU.
A sparse grid based method for generative dimensionality reduction of high-dimensional data
NASA Astrophysics Data System (ADS)
Bohn, Bastian; Garcke, Jochen; Griebel, Michael
2016-03-01
Generative dimensionality reduction methods play an important role in machine learning applications because they construct an explicit mapping from a low-dimensional space to the high-dimensional data space. We discuss a general framework to describe generative dimensionality reduction methods, where the main focus lies on a regularized principal manifold learning variant. Since most generative dimensionality reduction algorithms exploit the representer theorem for reproducing kernel Hilbert spaces, their computational costs grow at least quadratically in the number n of data. Instead, we introduce a grid-based discretization approach which automatically scales just linearly in n. To circumvent the curse of dimensionality of full tensor product grids, we use the concept of sparse grids. Furthermore, in real-world applications, some embedding directions are usually more important than others and it is reasonable to refine the underlying discretization space only in these directions. To this end, we employ a dimension-adaptive algorithm which is based on the ANOVA (analysis of variance) decomposition of a function. In particular, the reconstruction error is used to measure the quality of an embedding. As an application, the study of large simulation data from an engineering application in the automotive industry (car crash simulation) is performed.
Embedding recurrent neural networks into predator-prey models.
Moreau, Yves; Louiès, Stephane; Vandewalle, Joos; Brenig, Leon
1999-03-01
We study changes of coordinates that allow the embedding of ordinary differential equations describing continuous-time recurrent neural networks into differential equations describing predator-prey models-also called Lotka-Volterra systems. We transform the equations for the neural network first into quasi-monomial form (Brenig, L. (1988). Complete factorization and analytic solutions of generalized Lotka-Volterra equations. Physics Letters A, 133(7-8), 378-382), where we express the vector field of the dynamical system as a linear combination of products of powers of the variables. In practice, this transformation is possible only if the activation function is the hyperbolic tangent or the logistic sigmoid. From this quasi-monomial form, we can directly transform the system further into Lotka-Volterra equations. The resulting Lotka-Volterra system is of higher dimension than the original system, but the behavior of its first variables is equivalent to the behavior of the original neural network. We expect that this transformation will permit the application of existing techniques for the analysis of Lotka-Volterra systems to recurrent neural networks. Furthermore, our results show that Lotka-Volterra systems are universal approximators of dynamical systems, just as are continuous-time neural networks.
Supersymmetric solutions of the cosmological, gauged, ℂ magic model
NASA Astrophysics Data System (ADS)
Chimento, Samuele; Ortín, Tomás; Ruipérez, Alejandro
2018-05-01
We construct supersymmetric solutions of theories of gauged N = 1 , d = 5 supergravity coupled to vector multiplets with a U(1)R Abelian (Fayet-Iliopoulos) gauging and an independent SU(2) gauging associated to an SU(2) isometry group of the Real Special scalar manifold. These theories provide minimal supersymmetrizations of 5-dimensional SU(2) Einstein-Yang-Mills theories with negative cosmological constant. We consider a minimal model with these gauge groups and the "magic model" based on the Jordan algebra J 3 ℂ with gauge group SU(3) × U(1)R, which is a consistent truncation of maximal SO(6)-gauged supergravity in d = 5 and whose solutions can be embedded in Type IIB Superstring Theory. We find several solutions containing selfdual SU(2) instantons, some of which asymptote to AdS5 and some of which are very small, supersymmetric, deformations of AdS5. We also show how some of those solutions can be embedded in Romans' SU(2) × U(1)-gauged half-maximal supergravity, which was obtained by Lu, Pope and Tran by compactification of the Type IIB Superstring effective action. This provides another way of uplifting those solutions to 10 dimensions.
Miao, Ping; Lin, Xiaohuan; Koda, Akihiro; Lee, Sanghyun; Ishikawa, Yoshihisa; Torii, Shuki; Yonemura, Masao; Mochiku, Takashi; Sagayama, Hajime; Itoh, Shinichi; Ikeda, Kazutaka; Otomo, Toshiya; Wang, Yinxia; Kadono, Ryosuke; Kamiyama, Takashi
2017-07-01
Materials that show negative thermal expansion (NTE) have significant industrial merit because they can be used to fabricate composites whose dimensions remain invariant upon heating. In some materials, NTE is concomitant with the spontaneous magnetization due to the magnetovolume effect (MVE). Here the authors report a new class of MVE material; namely, a layered perovskite PrBaCo 2 O 5.5+ x (0 ≤ x ≤ 0.41), in which strong NTE [β ≈ -3.6 × 10 -5 K -1 (90-110 K) at x = 0.24] is triggered by embedding ferromagnetic (F) clusters into the antiferromagnetic (AF) matrix. The strongest MVE is found near the boundary between F and AF phases in the phase diagram, indicating the essential role of competition between the F-clusters and the AF-matrix. Furthermore, the MVE is not limited to the PrBaCo 2 O 5.5+ x but is also observed in the NdBaCo 2 O 5.5+ x . The present study provides a new approach to obtaining MVE and offers a path to the design of NTE materials. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Real-time 3-D ultrafast ultrasound quasi-static elastography in vivo
Papadacci, Clement; Bunting, Ethan A.; Konofagou, Elisa E.
2017-01-01
Ultrasound elastography, a technique used to assess mechanical properties of soft tissue is of major interest in the detection of breast cancer as it is stiffer than the surroundings. Techniques such as ultrasound quasi-static elastography have been developed to assess the strain distribution in soft tissues in two dimensions using a quasi-static compression. However, tumors can exhibit very heterogeneous shape, a three dimensions approach would be then necessary to measure accurately the tumor volume and remove operator dependency. To ensure this issue, several 3-D quasi-static elastographic approaches have been proposed. However, all these approaches suffered from a long acquisition time to acquire 3-D volumes resulting in the impossibility to perform real-time and the creation of artifacts. The long acquisition time comes from both the use of focused ultrasound emissions and the fact that the volume was made from a stack of two dimensions images acquired by mechanically translating an ultrasonic array. Being able to acquire volume at high volume rates is thus crucial to perform real-time with a simple freehand compression and to avoid signal decorrelation coming from hand motions or natural motions such as the respiratory. In this study we developed for the first time, the 3-D ultrafast ultrasound quasi-static elastography method to estimate 3-D axial strain distribution in vivo in real-time. Acquisitions were performed with a 2-D matrix array probe of 256 elements (16-by-16 elements). 100 plane waves were emitted at a volume rate of 100 volumes/sec during a continuous motorized compression. 3-D B-mode volumes and 3-D B-mode cumulative axial strain volumes were estimated on a two-layers gelatin phantom with different stiffness, in a stiff inclusion embedded in a soft gelatin phantoms, in a soft inclusion embedded in a stiff gelatin phantom and in an ex vivo canine liver before and after a high focused ultrasound (HIFU) ablation. In each case, we were able to image in real-time and in entire volumes the axial strain distribution and were able to detect the differences between stiff and soft structures with a good sensitivity. In addition, we were able to detect the stiff lesion in the ex vivo canine liver after HIFU ablation. Finally, we demonstrated the in vivo feasibility of the method using freehand compression on the calf of a human volunteer and were able to retrieve 3-D axial strain volume in real-time depicting the differences in stiffness of the two muscles which compose the calf. The 3-D ultrafast ultrasound quasi-static elastography method could have a major clinical impact for the real-time detection in three dimensions of breast cancer in patients using a simple freehand scanning. PMID:27483021
Hidden Markov models and neural networks for fault detection in dynamic systems
NASA Technical Reports Server (NTRS)
Smyth, Padhraic
1994-01-01
Neural networks plus hidden Markov models (HMM) can provide excellent detection and false alarm rate performance in fault detection applications, as shown in this viewgraph presentation. Modified models allow for novelty detection. Key contributions of neural network models are: (1) excellent nonparametric discrimination capability; (2) a good estimator of posterior state probabilities, even in high dimensions, and thus can be embedded within overall probabilistic model (HMM); and (3) simple to implement compared to other nonparametric models. Neural network/HMM monitoring model is currently being integrated with the new Deep Space Network (DSN) antenna controller software and will be on-line monitoring a new DSN 34-m antenna (DSS-24) by July, 1994.
Numerical Analysis of Deflections of Multi-Layered Beams
NASA Astrophysics Data System (ADS)
Biliński, Tadeusz; Socha, Tomasz
2015-03-01
The paper concerns the rheological bending problem of wooden beams reinforced with embedded composite bars. A theoretical model of the behaviour of a multi-layered beam is presented. The component materials of this beam are described with equations for the linear viscoelastic five-parameter rheological model. Two numerical analysis methods for the long-term response of wood structures are presented. The first method has been developed with SCILAB software. The second one has been developed with the finite element calculation software ABAQUS and user subroutine UMAT. Laboratory investigations were conducted on sample beams of natural dimensions in order to validate the proposed theoretical model and verify numerical simulations. Good agreement between experimental measurements and numerical results is observed.
Biofilm architecture of Phanerozoic cryptic carbonate marine veneers
NASA Astrophysics Data System (ADS)
Riding, Robert
2002-01-01
Thin (<150 μm) micritic veneers lining crypts in Paleozoic and Mesozoic reef, microbial, and bioclastic carbonates have the dimensions and architecture of modern uncalcified bacterial biofilm. Morphologic attributes include rounded aggregate nanofabric, internal channels, external towers, mushrooms, and plumes. All can be interpreted as characteristics of attached bacterial communities, i.e., aggregates as microcolonies, originally embedded in a matrix of extracellular polymeric substances; channels as water conduits and/or uncolonized nutrient-poor spaces; external protuberances as localized growths; and plumes as surface streamers. Cryptic habitat favored pristine biofilm preservation by precluding disturbance and overgrowth, and suggests aphotic and anoxic conditions. These examples provide diagnostic morphologic criteria for wider recognition of biofilm in Phanerozoic and older carbonates.
Analysis of Document Authentication Technique using Soft Magnetic Fibers
NASA Astrophysics Data System (ADS)
Aoki, Ayumi; Ikeda, Takashi; Yamada, Tsutomu; Takemura, Yasushi; Matsumoto, Tsutomu
An artifact-metric system using magnetic fibers can be applied for authentications of stock certificate, bill, passport, plastic cards and other documents. Security of the system is guaranteed by its feature of difficulty in copy. This authentication system is based on randomly dispersed magnetic fibers embedded in documents. In this paper, a theoretical analysis was performed in order to evaluate this system. The position of the magnetic fibers was determined by a conventional function of random number generator. By measuring output waveforms by a magnetoresistance (MR) sensor, a false match rate (FMR) could be calculated. Optimizations of the density of the magnetic fibers and the dimension of the MR sensor were achieved.
Moloney, Gail; Hall, Rob; Walker, Iain
2005-09-01
This study extends previous research investigating the social representation of organ donation and transplantation (Moloney & Walker, 2000, 2002) by exploring the accommodation of contradiction (Wagner, Duveen, Verma, & Thelmel, 2000) within consensual reality (Rose et al., 1995), and the role of themata (Markova, 2000) in a representation. The study employed a mail-out questionnaire embedded with eight experimental conditions, which manipulated two tasks, scenario rating scale and word association. WMDS (INDSCAL) analyses demonstrated that the dialectical concepts of life and death are generative of a contradictory representational field that is maintained through the differential elicitation of the normative and functional dimensions (Guimelli, 1998) of the representation in accordance with social context.
Photon-induced formation of CdS nanocrystals in selected areas of polymer matrices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Athanassiou, Athanassia; Cingolani, Roberto; Tsiranidou, Elsa
2007-10-08
We demonstrate light-induced formation of semiconductor quantum dots in TOPAS registered polymer matrix with very high control of their size and their spatial localization. Irradiation with UV laser pulses of polymer films embedding Cd thiolate precursors results in the formation of cadmium sulfide nanocrystals well confined in the irradiation area, through a macroscopically nondestructive procedure for the host matrix. With increasing number of laser pulses, we accomplish the formation of nanoparticles with gradually increasing dimensions, resulting in the dynamic change of the spectra emitted by the formed nanocomposite areas. The findings are supported by x-ray diffraction and transmission electron microscopymore » measurements.« less