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1

The multi-dimensional model of M?ori identity and cultural engagement: item response theory analysis of scale properties.  

PubMed

We argue that there is a need for culture-specific measures of identity that delineate the factors that most make sense for specific cultural groups. One such measure, recently developed specifically for M?ori peoples, is the Multi-Dimensional Model of M?ori Identity and Cultural Engagement (MMM-ICE). M?ori are the indigenous peoples of New Zealand. The MMM-ICE is a 6-factor measure that assesses the following aspects of identity and cultural engagement as M?ori: (a) group membership evaluation, (b) socio-political consciousness, (c) cultural efficacy and active identity engagement, (d) spirituality, (e) interdependent self-concept, and (f) authenticity beliefs. This article examines the scale properties of the MMM-ICE using item response theory (IRT) analysis in a sample of 492 M?ori. The MMM-ICE subscales showed reasonably even levels of measurement precision across the latent trait range. Analysis of age (cohort) effects further indicated that most aspects of M?ori identification tended to be higher among older M?ori, and these cohort effects were similar for both men and women. This study provides novel support for the reliability and measurement precision of the MMM-ICE. The study also provides a first step in exploring change and stability in M?ori identity across the life span. A copy of the scale, along with recommendations for scale scoring, is included. PMID:23356361

Sibley, Chris G; Houkamau, Carla A

2013-01-01

2

Reconstruction of network structures from marked point processes using multi-dimensional scaling  

NASA Astrophysics Data System (ADS)

We propose a method of estimating network structures only from observed marked point processes using the multi-dimensional scaling. In this method, first, we calculate a spike time metric which quantifies a metric distance between the observed marked point processes. Next, to represent a relationship among point processes in the Euclidean space, we apply the multi-dimensional scaling to the metric distance between point processes. Then we apply the partialization analysis to the obtained coordinate vectors by the multi-dimensional scaling. As a result, we can estimate the network structures from multiple point processes even though the elements have many common spurious inputs from the other elements.

Kuroda, Kaori; Hashiguchi, Hiroki; Fujiwara, Kantaro; Ikeguchi, Tohru

2014-12-01

3

Multi-dimensional residual analysis of point process models for earthquake occurrences.  

E-print Network

Multi-dimensional residual analysis of point process models for earthquake occurrences. Frederic methods for examining the fit of multi-dimensional point process models are applied to point process model, seismology, separability. 1 Introduction. Stochastic point process models have become essential

Schoenberg, Frederic Paik (Rick)

4

Coupling visualization and data analysis for knowledge discovery from multi-dimensional scientific data  

PubMed Central

Knowledge discovery from large and complex scientific data is a challenging task. With the ability to measure and simulate more processes at increasingly finer spatial and temporal scales, the growing number of data dimensions and data objects presents tremendous challenges for effective data analysis and data exploration methods and tools. The combination and close integration of methods from scientific visualization, information visualization, automated data analysis, and other enabling technologies —such as efficient data management— supports knowledge discovery from multi-dimensional scientific data. This paper surveys two distinct applications in developmental biology and accelerator physics, illustrating the effectiveness of the described approach. PMID:23762211

Rübel, Oliver; Ahern, Sean; Bethel, E. Wes; Biggin, Mark D.; Childs, Hank; Cormier-Michel, Estelle; DePace, Angela; Eisen, Michael B.; Fowlkes, Charless C.; Geddes, Cameron G. R.; Hagen, Hans; Hamann, Bernd; Huang, Min-Yu; Keränen, Soile V. E.; Knowles, David W.; Hendriks, Cris L. Luengo; Malik, Jitendra; Meredith, Jeremy; Messmer, Peter; Prabhat; Ushizima, Daniela; Weber, Gunther H.; Wu, Kesheng

2013-01-01

5

A Monte Carlo Evaluation of Interactive Multi-dimensional Scaling  

ERIC Educational Resources Information Center

An experimental procedure involving interaction between subject and computer was used to determine an opitmum subset of stimuli for multidimensional scaling (MDS). A computer program evaluated this procedure compared with MDS based on (a) all pairs of stimuli, and (b) on one-third of the possible pairs. The new method was better. (Author/HG)

Girard, Roger A.; Cliff, Norman

1976-01-01

6

How Fitch-Margoliash Algorithm can Benefit from Multi Dimensional Scaling  

PubMed Central

Whatever the phylogenetic method, genetic sequences are often described as strings of characters, thus molecular sequences can be viewed as elements of a multi-dimensional space. As a consequence, studying motion in this space (ie, the evolutionary process) must deal with the amazing features of high-dimensional spaces like concentration of measured phenomenon. To study how these features might influence phylogeny reconstructions, we examined a particular popular method: the Fitch-Margoliash algorithm, which belongs to the Least Squares methods. We show that the Least Squares methods are closely related to Multi Dimensional Scaling. Indeed, criteria for Fitch-Margoliash and Sammon’s mapping are somewhat similar. However, the prolific research in Multi Dimensional Scaling has definitely allowed outclassing Sammon’s mapping. Least Square methods for tree reconstruction can now take advantage of these improvements. However, “false neighborhood” and “tears” are the two main risks in dimensionality reduction field: “false neighborhood” corresponds to a widely separated data in the original space that are found close in representation space, and neighbor data that are displayed in remote positions constitute a “tear”. To address this problem, we took advantage of the concepts of “continuity” and “trustworthiness” in the tree reconstruction field, which limit the risk of “false neighborhood” and “tears”. We also point out the concentration of measured phenomenon as a source of error and introduce here new criteria to build phylogenies with improved preservation of distances and robustness. The authors and the Evolutionary Bioinformatics Journal dedicate this article to the memory of Professor W.M. Fitch (1929–2011). PMID:21697992

Lespinats, Sylvain; Grando, Delphine; Marechal, Eric; Hakimi, Mohamed-Ali; Tenaillon, Olivier; Bastien, Olivier

2011-01-01

7

How Fitch-Margoliash Algorithm can Benefit from Multi Dimensional Scaling.  

PubMed

Whatever the phylogenetic method, genetic sequences are often described as strings of characters, thus molecular sequences can be viewed as elements of a multi-dimensional space. As a consequence, studying motion in this space (ie, the evolutionary process) must deal with the amazing features of high-dimensional spaces like concentration of measured phenomenon.TO STUDY HOW THESE FEATURES MIGHT INFLUENCE PHYLOGENY RECONSTRUCTIONS, WE EXAMINED A PARTICULAR POPULAR METHOD: the Fitch-Margoliash algorithm, which belongs to the Least Squares methods. We show that the Least Squares methods are closely related to Multi Dimensional Scaling. Indeed, criteria for Fitch-Margoliash and Sammon's mapping are somewhat similar. However, the prolific research in Multi Dimensional Scaling has definitely allowed outclassing Sammon's mapping.Least Square methods for tree reconstruction can now take advantage of these improvements. However, "false neighborhood" and "tears" are the two main risks in dimensionality reduction field: "false neighborhood" corresponds to a widely separated data in the original space that are found close in representation space, and neighbor data that are displayed in remote positions constitute a "tear". To address this problem, we took advantage of the concepts of "continuity" and "trustworthiness" in the tree reconstruction field, which limit the risk of "false neighborhood" and "tears". We also point out the concentration of measured phenomenon as a source of error and introduce here new criteria to build phylogenies with improved preservation of distances and robustness.The authors and the Evolutionary Bioinformatics Journal dedicate this article to the memory of Professor W.M. Fitch (1929-2011). PMID:21697992

Lespinats, Sylvain; Grando, Delphine; Maréchal, Eric; Hakimi, Mohamed-Ali; Tenaillon, Olivier; Bastien, Olivier

2011-01-01

8

MultiDimensional Analysis of International Social Indicators – Education, Economy, Media and Demography  

Microsoft Academic Search

Using multi-dimensional analysis methods, it ispossible to uncover a structure representing therelationship between multiple internationaleducational, social and economic indicators. In thisstudy, we applied Smallest Space Analysis to datacollected by international agencies for 138 countriesand 20 indicators. A preliminary structure was foundand replicated for different data sets. Thisstructural interrelationship shows that these variousindicators are part of a larger field called welfare.This

Erik H. Cohen

2000-01-01

9

A Multi-Dimensional Cognitive Analysis of Undergraduate Physics Students' Understanding of Heat Conduction  

ERIC Educational Resources Information Center

This study proposes a multi-dimensional approach to investigate, represent, and categorize students' in-depth understanding of complex physics concepts. Clinical interviews were conducted with 30 undergraduate physics students to probe their understanding of heat conduction. Based on the data analysis, six aspects of the participants' responses…

Chiou, Guo-Li; Anderson, O. Roger

2010-01-01

10

Multi-dimensional modeling of large-scale lithium-ion batteries  

NASA Astrophysics Data System (ADS)

Multi-dimensional model of large-scale lithium-ion batteries is developed. The model is based on equivalent circuit model (ECM) which is capable of dynamic response simulation. Model parameters are functions of both state of charge and temperature, which are implemented by bilinear interpolation method. Local degradation effects such as capacity fade and resistance growth are incorporated into the multi-D model by empirical method. Local distributions of current, potential, temperature, state of charge (SOC), and state of health (SOH) are observed with the developed model. It is found that local degradation worsens under severe operating condition. Low thermal conductivity of a battery results in non-uniform SOH distribution. Simulation result shows good agreement with experiment data under various operation modes.

Jung, Seunghun; Kang, Dalmo

2014-02-01

11

AstroMD. A multi-dimensional data analysis tool for astrophysical simulations  

E-print Network

Over the past few years, the role of visualization for scientific purpose has grown up enormously. Astronomy makes an extended use of visualization techniques to analyze data, and scientific visualization has became a fundamental part of modern researches in Astronomy. With the evolution of high performance computers, numerical simulations have assumed a great role in the scientific investigation, allowing the user to run simulation with higher and higher resolution. Data produced in these simulations are often multi-dimensional arrays with several physical quantities. These data are very hard to manage and to analyze efficiently. Consequently the data analysis and visualization tools must follow the new requirements of the research. AstroMD is a tool for data analysis and visualization of astrophysical data and can manage different physical quantities and multi-dimensional data sets. The tool uses virtual reality techniques by which the user has the impression of travelling through a computer-based multi-dimensional model. AstroMD is a freely available tool for the whole astronomical community (http://www.cineca.it/astromd/).

U. Becciani; V. Antonuccio-Delogu; C. Gheller; L. Calori; F. Buonomo; S. Imboden

2000-06-28

12

Method of multi-dimensional moment analysis for the characterization of signal peaks  

DOEpatents

A method of multi-dimensional moment analysis for the characterization of signal peaks can be used to optimize the operation of an analytical system. With a two-dimensional Peclet analysis, the quality and signal fidelity of peaks in a two-dimensional experimental space can be analyzed and scored. This method is particularly useful in determining optimum operational parameters for an analytical system which requires the automated analysis of large numbers of analyte data peaks. For example, the method can be used to optimize analytical systems including an ion mobility spectrometer that uses a temperature stepped desorption technique for the detection of explosive mixtures.

Pfeifer, Kent B; Yelton, William G; Kerr, Dayle R; Bouchier, Francis A

2012-10-23

13

SIGMA2: A system for the integrative genomic multi-dimensional analysis of cancer genomes, epigenomes, and transcriptomes  

Microsoft Academic Search

Background: High throughput microarray technologies have afforded the investigation of genomes, epigenomes, and transcriptomes at unprecedented resolution. However, software packages to handle, analyze, and visualize data from these multiple 'omics disciplines have not been adequately developed. Results: Here, we present SIGMA2, a system for the integrative genomic multi-dimensional analysis of cancer genomes, epigenomes, and transcriptomes. Multi-dimensional datasets can be simultaneously

Raj Chari; Bradley P. Coe; Craig Wedseltoft; Marie Benetti; Ian M. Wilson; Emily A. Vucic; Calum Macaulay; Raymond T. Ng; Wan L. Lam

2008-01-01

14

Overview of Computer-Aided Engineering of Batteries and Introduction to Multi-Scale, Multi-Dimensional Modeling of Li-Ion Batteries (Presentation)  

SciTech Connect

This 2012 Annual Merit Review presentation gives an overview of the Computer-Aided Engineering of Batteries (CAEBAT) project and introduces the Multi-Scale, Multi-Dimensional model for modeling lithium-ion batteries for electric vehicles.

Pesaran, A.; Kim, G. H.; Smith, K.; Santhanagopalan, S.; Lee, K. J.

2012-05-01

15

The use of multi-dimensional flow and morphodynamic models for restoration design analysis  

NASA Astrophysics Data System (ADS)

River restoration projects with the goal of restoring a wide range of morphologic and ecologic channel processes and functions have become common. The complex interactions between flow and sediment-transport make it challenging to design river channels that are both self-sustaining and improve ecosystem function. The relative immaturity of the field of river restoration and shortcomings in existing methodologies for evaluating channel designs contribute to this problem, often leading to project failures. The call for increased monitoring of constructed channels to evaluate which restoration techniques do and do not work is ubiquitous and may lead to improved channel restoration projects. However, an alternative approach is to detect project flaws before the channels are built by using numerical models to simulate hydraulic and sediment-transport processes and habitat in the proposed channel (Restoration Design Analysis). Multi-dimensional models provide spatially distributed quantities throughout the project domain that may be used to quantitatively evaluate restoration designs for such important metrics as (1) the change in water-surface elevation which can affect the extent and duration of floodplain reconnection, (2) sediment-transport and morphologic change which can affect the channel stability and long-term maintenance of the design; and (3) habitat changes. These models also provide an efficient way to evaluate such quantities over a range of appropriate discharges including low-probability events which often prove the greatest risk to the long-term stability of restored channels. Currently there are many free and open-source modeling frameworks available for such analysis including iRIC, Delft3D, and TELEMAC. In this presentation we give examples of Restoration Design Analysis for each of the metrics above from projects on the Russian River, CA and the Kootenai River, ID. These examples demonstrate how detailed Restoration Design Analysis can be used to guide design elements and how this method can point out potential stability problems or other risks before designs proceed to the construction phase.

McDonald, R.; Nelson, J. M.

2013-12-01

16

Data-mining Analysis and Multi-dimensional Visualization of Earthquake Clusters in a GRID-Like Interactive Environment  

NASA Astrophysics Data System (ADS)

We have developed an interactive web-based scheme for data-mining the spatio-temporal patterns of many earthquakes. This novel technique is based on cluster analysis of the multi-resolutional structures of earthquakes. The interactive scheme is based on a client-server paradigm in which we have used the off-screen rendering technique to facilitate the visual interrogation. A powerful 3-D visualization package Amira ( www.amiravis.com ) is also used to visualize the complex clusteral patte nrs in a reduced dimensional space. We have applied our method to observed and synthetic tic seismic catalogs. The observed data represent seismic activities situated around the Japanese islands in the 1997-2003 time interval. The synthetic data were generated by numerical simulations for various cases of a heterogeneous fault governed by quasi-analytical 3-D elastic dislocation models .At the highest resolution, we analyze the local cluster structure in the data space of seismic events for the two types of catalogs by using an agglomerative clustering algorithm. We demonstrate that small magnitude events produce local spatio-temporal patches corresponding to neighboring large events. Seismic events, quantized in space and time, generate the multi-dimensional feature space of the earthquake parameters. Using a non-hierarchical clustering algorithm and multi-dimensional scaling, we explore the multitudinous earthquakes by real-time 3-D visualization and inspection of multivariate clusters. At the resolutions characteristic of the earthquake parameters, all of the ongoing seismicity before and after largest events accumulate to a global structure consisting of a few separate clusters in the feature space . We show that by combining the clustering results from low and high resolution spaces, we can recognize precursory events more precisely. We will discuss how this WEB-IS ( Web-Interrrogative system ) would work. One can also access this by going to the URL http://boy.msi.umn.edu/web-is/. Its implementation and deployment in light of future GRID-computing will be discussed in terms of the recently developed Narada-Brokering (distributed messaging ) system of publishing and subscribing . This will provide a scalable infrastructure for several applications involving a set of nodes communicating with each other. .

Yuen, D. A.; Dzwinel, W.; Bollig, E. F.; Kadlec, B. F.; Ben-Zion, Y.; Yoshioka, S.

2003-12-01

17

Measuring the Effectiveness of Advertising in a Positioning Context with Multi Dimensional Scaling Techniques.  

National Technical Information Service (NTIS)

Measuring the effectiveness of advertising in the context of positioning can easily be accomplished by multidimensional scaling (MDS)-procedures and the Index of Effectiveness (IE). However, many problems have to be eliminated. Most problems arise from th...

M. Versteijne

1988-01-01

18

Relationships between Organizations and Publics: Development of a Multi-Dimensional Organization-Public Relationship Scale.  

ERIC Educational Resources Information Center

Attempts to design a multiple-item, multiple-dimension organization/public relationship scale. Finds that organizations and key publics have three types of relationships: professional, personal, and community. Provides an instrument that can be used to measure the influence that perceptions of the organization/public relationship have on consumer…

Bruning, Stephen D.; Ledingham, John A.

1999-01-01

19

Psychophysical similarity measure based on multi-dimensional scaling for retrieval of similar images of breast masses on mammograms  

NASA Astrophysics Data System (ADS)

For retrieving reference images which may be useful to radiologists in their diagnosis, it is necessary to determine a reliable similarity measure which would agree with radiologists' subjective impression. In this study, we propose a new similarity measure for retrieval of similar images, which may assist radiologists in the distinction between benign and malignant masses on mammograms, and investigated its usefulness. In our previous study, to take into account the subjective impression, the psychophysical similarity measure was determined by use of an artificial neural network (ANN), which was employed to learn the relationship between radiologists' subjective similarity ratings and image features. In this study, we propose a psychophysical similarity measure based on multi-dimensional scaling (MDS) in order to improve the accuracy in retrieval of similar images. Twenty-seven images of masses, 3 each from 9 different pathologic groups, were selected, and the subjective similarity ratings for all possible 351 pairs were determined by 8 expert physicians. MDS was applied using the average subjective ratings, and the relationship between each output axis and image features was modeled by the ANN. The MDS-based psychophysical measures were determined by the distance in the modeled space. With a leave-one-out test method, the conventional psychophysical similarity measure was moderately correlated with subjective similarity ratings (r=0.68), whereas the psychophysical measure based on MDS was highly correlated (r=0.81). The result indicates that a psychophysical similarity measure based on MDS would be useful in the retrieval of similar images.

Nishimura, Kohei; Muramatsu, Chisako; Oiwa, Mikinao; Shiraiwa, Misaki; Endo, Tokiko; Doi, Kunio; Fujita, Hiroshi

2013-02-01

20

Similarity from Multi-Dimensional Scaling: Solving the Accuracy and Diversity Dilemma in Information Filtering  

PubMed Central

Recommender systems are designed to assist individual users to navigate through the rapidly growing amount of information. One of the most successful recommendation techniques is the collaborative filtering, which has been extensively investigated and has already found wide applications in e-commerce. One of challenges in this algorithm is how to accurately quantify the similarities of user pairs and item pairs. In this paper, we employ the multidimensional scaling (MDS) method to measure the similarities between nodes in user-item bipartite networks. The MDS method can extract the essential similarity information from the networks by smoothing out noise, which provides a graphical display of the structure of the networks. With the similarity measured from MDS, we find that the item-based collaborative filtering algorithm can outperform the diffusion-based recommendation algorithms. Moreover, we show that this method tends to recommend unpopular items and increase the global diversification of the networks in long term. PMID:25343243

Zeng, Wei; Zeng, An; Liu, Hao; Shang, Ming-Sheng; Zhang, Yi-Cheng

2014-01-01

21

Similarity from multi-dimensional scaling: solving the accuracy and diversity dilemma in information filtering.  

PubMed

Recommender systems are designed to assist individual users to navigate through the rapidly growing amount of information. One of the most successful recommendation techniques is the collaborative filtering, which has been extensively investigated and has already found wide applications in e-commerce. One of challenges in this algorithm is how to accurately quantify the similarities of user pairs and item pairs. In this paper, we employ the multidimensional scaling (MDS) method to measure the similarities between nodes in user-item bipartite networks. The MDS method can extract the essential similarity information from the networks by smoothing out noise, which provides a graphical display of the structure of the networks. With the similarity measured from MDS, we find that the item-based collaborative filtering algorithm can outperform the diffusion-based recommendation algorithms. Moreover, we show that this method tends to recommend unpopular items and increase the global diversification of the networks in long term. PMID:25343243

Zeng, Wei; Zeng, An; Liu, Hao; Shang, Ming-Sheng; Zhang, Yi-Cheng

2014-01-01

22

CTH: A software family for multi-dimensional shock physics analysis  

SciTech Connect

CTH is a family of codes developed at Sandia National Laboratories for modeling complex multi-dimensional, multi-material problems that are characterized by large deformations and/or strong shocks. A two-step, second-order accurate Eulerian solution algorithm is used to solve the mass, momentum, and energy conservation equations. CTH includes models for material strength, fracture, porous materials, and high explosive detonation and initiation. Viscoplastic or rate-dependent models of material strength have been added recently. The formulations of Johnson-Cook, Zerilli-Armstrong, and Steinberg-Guinan-Lund are standard options within CTH. These models rely on using an internal state variable to account for the history dependence of material response. The implementation of internal state variable models will be discussed and several sample calculations will be presented. Comparison with experimental data will be made among the various material strength models. The advancements made in modelling material response have significantly improved the ability of CTH to model complex large-deformation, plastic-flow dominated phenomena. Detonation of energetic material under shock loading conditions has been of great interest. A recently developed model of reactive burn for high explosives (HE) has been added to CTH. This model along with newly developed tabular equations-of-state for the HE reaction by-products has been compared to one- and two-dimensional explosive detonation experiments. These comparisons indicate excellent agreement of CTH predictions with experimental results. The new reactive burn model coupled with the advances in equation-of-state modeling make it possible to predict multi-dimensional burn phenomena without modifying the model parameters for different dimensionality. Examples of the features of CTH will be given. The emphasis in simulations shown will be in comparison with well characterized experiments covering key phenomena of shock physics.

Hertel, E.S. Jr.; Bell, R.L.; Elrick, M.G.; Farnsworth, A.V.; Kerley, G.I.; McGlaun, J.M.; Petney, S.V.; Silling, S.A.; Taylor, P.A.; Yarrington, L.

1992-12-31

23

Multi-dimensional Meta-analysis for Assessment of Relationships between Asthma Rates and Particulate Air Pollution  

E-print Network

Multi-dimensional meta-analysis (MDMA) is an innovative technique for investigating complex scientific problems influenced by "external" factors, such as social, medical, economic, political or climatic trends. MDMA extends traditional meta-analysis by identifying significant data from diverse and independent disciplines ("orthogonal dimensions") and incorporating truth tables and non-parametric analysis methods in the interpretation protocol. In this paper, we outline the methodology of MDMA. We then demonstrates how to apply the method to a specific problem: the relationship between asthma and air particulates. The conclusions from the example show that the further reduction of atmospheric particulate levels is not necessarily the answer to the increasing asthma incidence. This example also demonstrates the strength of this method of analysis for complex problems.

J. I. Brand; M. S. Hallbeck; S. M. Ryan

2001-01-18

24

Validation of the multi-dimensional scale of perceived social support (MSPSS) and the relationship between social support, intimate partner violence and antenatal depression in Malawi  

PubMed Central

Background Lack of social support is an important risk factor for antenatal depression and anxiety in low- and middle-income countries. We translated, adapted and validated the Multi-dimensional Scale of Perceived Social Support (MSPSS) in order to study the relationship between perceived social support, intimate partner violence and antenatal depression in Malawi. Methods The MSPSS was translated and adapted into Chichewa and Chiyao. Five hundred and eighty-three women attending an antenatal clinic were administered the MSPSS, depression screening measures, and a risk factor questionnaire including questions about intimate partner violence. A sub-sample of participants (n?=?196) were interviewed using the Structured Clinical Interview for DSM-IV to diagnose major depressive episode. Validity of the MSPSS was evaluated by assessment of internal consistency, factor structure, and correlation with Self Reporting Questionnaire (SRQ) score and major depressive episode. We investigated associations between perception of support from different sources (significant other, family, and friends) and major depressive episode, and whether intimate partner violence was a moderator of these associations. Results In both Chichewa and Chiyao, the MSPSS had high internal consistency for the full scale and significant other, family, and friends subscales. MSPSS full scale and subscale scores were inversely associated with SRQ score and major depression diagnosis. Using principal components analysis, the MSPSS had the expected 3-factor structure in analysis of the whole sample. On confirmatory factor analysis, goodness–of-fit indices were better for a 3-factor model than for a 2-factor model, and met standard criteria when correlation between items was allowed. Lack of support from a significant other was the only MSPSS subscale that showed a significant association with depression on multivariate analysis, and this association was moderated by experience of intimate partner violence. Conclusions The MSPSS is a valid measure of perceived social support in Malawi. Lack of support by a significant other is associated with depression in pregnant women who have experienced intimate partner violence in this setting. PMID:24938124

2014-01-01

25

Integrative analysis of multi-dimensional imaging genomics data for Alzheimer's disease prediction  

PubMed Central

In this paper, we explore the effects of integrating multi-dimensional imaging genomics data for Alzheimer's disease (AD) prediction using machine learning approaches. Precisely, we compare our three recent proposed feature selection methods [i.e., multiple kernel learning (MKL), high-order graph matching based feature selection (HGM-FS), sparse multimodal learning (SMML)] using four widely-used modalities [i.e., magnetic resonance imaging (MRI), positron emission tomography (PET), cerebrospinal fluid (CSF), and genetic modality single-nucleotide polymorphism (SNP)]. This study demonstrates the performance of each method using these modalities individually or integratively, and may be valuable to clinical tests in practice. Our experimental results suggest that for AD prediction, in general, (1) in terms of accuracy, PET is the best modality; (2) Even though the discriminant power of genetic SNP features is weak, adding this modality to other modalities does help improve the classification accuracy; (3) HGM-FS works best among the three feature selection methods; (4) Some of the selected features are shared by all the feature selection methods, which may have high correlation with the disease. Using all the modalities on the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset, the best accuracies, described as (mean ± standard deviation)%, among the three methods are (76.2 ± 11.3)% for AD vs. MCI, (94.8 ± 7.3)% for AD vs. HC, (76.5 ± 11.1)% for MCI vs. HC, and (71.0 ± 8.4)% for AD vs. MCI vs. HC, respectively. PMID:25368574

Zhang, Ziming; Huang, Heng; Shen, Dinggang

2014-01-01

26

Pedagogic discourse in introductory classes: Multi-dimensional analysis of textbooks and lectures in biology and macroeconomics  

NASA Astrophysics Data System (ADS)

The broad goal of this study is to represent the linguistic variation of textbooks and lectures, the primary input for student learning---and sometimes the sole input in the large introductory classes which characterize General Education at many state universities. Computer techniques are used to analyze a corpus of textbooks and lectures from first-year university classes in macroeconomics and biology. These spoken and written variants are compared to each other as well as to benchmark texts from other multi-dimensional studies in order to examine their patterns, relations, and functions. A corpus consisting of 147,000 words was created from macroeconomics and biology lectures at a medium-large state university and from a set of nationally "best-selling" textbooks used in these same introductory survey courses. The corpus was analyzed using multi-dimensional methodology (Biber, 1988). The analysis consists of both empirical and qualitative phases. Quantitative analyses are undertaken on the linguistic features, their patterns of co-occurrence, and on the contextual elements of classrooms and textbooks. The contextual analysis is used to functionally interpret the statistical patterns of co-occurrence along five dimensions of textual variation, demonstrating patterns of difference and similarity with reference to text excerpts. Results of the analysis suggest that academic discourse is far from monolithic. Pedagogic discourse in introductory classes varies by modality and discipline, but not always in the directions expected. In the present study the most abstract texts were biology lectures---more abstract than written genres of academic prose and more abstract than introductory textbooks. Academic lectures in both disciplines, monologues which carry a heavy informational load, were extremely interactive, more like conversation than academic prose. A third finding suggests that introductory survey textbooks differ from those used in upper division classes by being relatively less marked for information density, abstraction, and non-overt argumentation. In addition to the findings mentioned here, numerous other relationships among the texts exhibit complex patterns of variation related to a number of situational variables. Pedagogical implications are discussed in relation to General Education courses, differing student populations, and the reading and listening demands which students encounter in large introductory classes in the university.

Carkin, Susan

27

Multi-dimensional analysis of the chemical and physical properties of spiral galaxies  

E-print Network

in the ultraviolet (which normally appears as a blended ?3727 line on low-dispersion spectrograms). In addition, the permitted lines of hydrogen, H? ?6563 in the red, H? ?4861 in the blue, H? ?4340 in the violet and so on, are characteristic features of every nebular... , by the application of the Integral Field Spectroscopy (IFS) technique. The semi-continuous coverage spectra provided by this spectral imaging technique allows to study the small and intermediate linear scale variation in line emission and the gas chemistry...

Rosales Ortega, Fernando Fabián

2010-02-09

28

Microscale isoelectric fractionation using immobilized pH-specific membranes for multi-dimensional analysis.  

SciTech Connect

We report on advancements of our microscale isoelectric fractionation ({mu}IEFr) methodology for fast on-chip separation and concentration of proteins based on their isoelectric points (pI). We establish that proteins can be fractionated depending on posttranslational modifications into different pH specific bins, from where they can be efficiently transferred to downstream membranes for additional processing and analysis. This technology can enable on-chip multidimensional glycoproteomics analysis, as a new approach to expedite biomarker identification and verification.

Mai, Junyu; Sommer, Gregory Jon; Hatch, Anson V.

2010-10-01

29

Scaling the ISLE Taxonomy: Development of Metrics for the MultiDimensional Characterisation of Machine Translation Quality  

Microsoft Academic Search

The DARPA MT evaluations of the early 1990s, along with subsequent work on the MT Scale, and the International Standards for Language Engineering (ISLE) MT Evaluation framework represent two of the principal efforts in Machine Translation Evaluation (MTE) over the past decade. We describe a research program that builds on both of these efforts. This paper focuses on the selection

Keith J. Miller; Michelle Vanni

30

Data Mining in Multi-Dimensional Functional Data for Manufacturing Fault Diagnosis  

SciTech Connect

Multi-dimensional functional data, such as time series data and images from manufacturing processes, have been used for fault detection and quality improvement in many engineering applications such as automobile manufacturing, semiconductor manufacturing, and nano-machining systems. Extracting interesting and useful features from multi-dimensional functional data for manufacturing fault diagnosis is more difficult than extracting the corresponding patterns from traditional numeric and categorical data due to the complexity of functional data types, high correlation, and nonstationary nature of the data. This chapter discusses accomplishments and research issues of multi-dimensional functional data mining in the following areas: dimensionality reduction for functional data, multi-scale fault diagnosis, misalignment prediction of rotating machinery, and agricultural product inspection based on hyperspectral image analysis.

Jeong, Myong K [ORNL; Kong, Seong G [ORNL; Omitaomu, Olufemi A [ORNL

2008-09-01

31

Perceptual Dominant Color Extraction by Multi-Dimensional Particle Swarm Optimization 1 Abstract--Color is the major source of information widely used in image analysis and content-based retrieval.  

E-print Network

of color patterns. One observation worth mentioning here is that the human eye cannot perceive a largePerceptual Dominant Color Extraction by Multi-Dimensional Particle Swarm Optimization 1 Abstract-- Color is the major source of information widely used in image analysis and content-based retrieval

Gabbouj, Moncef

32

Optimization of a sample preparation method for multiresidue analysis of pesticides in tobacco by single and multi-dimensional gas chromatography-mass spectrometry.  

PubMed

A selective and sensitive multiresidue analysis method, comprising 4 7pesticides, was developed and validated in tobacco matrix. The optimized sample preparation procedure in combination with gas chromatography mass spectrometry in selected-ion-monitoring (GC-MS/SIM) mode offered limits of detection (LOD) and quantification (LOQ) in the range of 3-5 and 7.5-15ng/g, respectively, with recoveries between 70 and 119% at 50-100ng/g fortifications. In comparison to the modified QuEChERS (Quick-Easy-Cheap-Effective-Rugged-Safe method: 2g tobacco+10ml water+10ml acetonitrile, 30min vortexing, followed by dispersive solid phase extraction cleanup), the method performed better in minimizing matrix co-extractives e.g. nicotine and megastigmatrienone. Ambiguity in analysis due to co-elution of target analytes (e.g. transfluthrin-heptachlor) and with matrix co-extractives (e.g. ?-HCH-neophytadiene, 2,4-DDE-linolenic acid) could be resolved by selective multi-dimensional (MD)GC heart-cuts. The method holds promise in routine analysis owing to noticeable efficiency of 27 samples/person/day. PMID:24746872

Khan, Zareen S; Ghosh, Rakesh Kumar; Girame, Rushali; Utture, Sagar C; Gadgil, Manasi; Banerjee, Kaushik; Reddy, D Damodar; Johnson, Nalli

2014-05-23

33

Multi-Dimensional Analysis of Large, Complex Slope Instability: Case study of Downie Slide, British Columbia, Canada. (Invited)  

NASA Astrophysics Data System (ADS)

Downie Slide, one of the world's largest landslides, is a massive, active, composite, extremely slow rockslide located on the west bank of the Revelstoke Reservoir in British Columbia. It is a 1.5 billion m3 rockslide measuring 2400 m along the river valley, 3300m from toe to headscarp and up to 245 m thick. Significant contributions to the field of landslide geomechanics have been made by analyses of spatially and temporally discriminated slope deformations, and how these are controlled by complex geological and geotechnical factors. Downie Slide research demonstrates the importance of delineating massive landslides into morphological regions in order to characterize global slope behaviour and identify localized events, which may or may not influence the overall slope deformation patterns. Massive slope instabilities do not behave as monolithic masses, rather, different landslide zones can display specific landslide processes occurring at variable rates of deformation. The global deformation of Downie Slide is extremely slow moving; however localized regions of the slope incur moderate to high rates of movement. Complex deformation processes and composite failure mechanism are contributed to by topography, non-uniform shear surfaces, heterogeneous rockmass and shear zone strength and stiffness characteristics. Further, from the analysis of temporal changes in landslide behaviour it has been clearly recognized that different regions of the slope respond differently to changing hydrogeological boundary conditions. State-of-the-art methodologies have been developed for numerical simulation of large landslides; these provide important tools for investigating dynamic landslide systems which account for complex three-dimensional geometries, heterogenous shear zone strength parameters, internal shear zones, the interaction of discrete landslide zones and piezometric fluctuations. Numerical models of Downie Slide have been calibrated to reproduce observed slope behaviour, and the calibration process has provided important insight to key factors controlling massive slope mechanics. Through numerical studies it has been shown that the three-dimensional interpretation of basal slip surface geometry and spatial heterogeneity in shear zone stiffness are important factors controlling large-scale slope deformation processes. The role of secondary internal shears and the interaction between landslide morphological zones has also been assessed. Further, numerical simulation of changing groundwater conditions has produced reasonable correlation with field observations. Calibrated models are valuable tools for the forward prediction of landslide dynamics. Calibrated Downie Slide models have been used to investigate how trigger scenarios may accelerate deformations at Downie Slide. The ability to reproduce observed behaviour and forward test hypothesized changes to boundary conditions has valuable application in hazard management of massive landslides. The capacity of decision makers to interpret large amounts of data, respond to rapid changes in a system and understand complex slope dynamics has been enhanced.

Kalenchuk, K. S.; Hutchinson, D.; Diederichs, M. S.

2013-12-01

34

Multi-dimensional real Fourier transform  

NASA Technical Reports Server (NTRS)

Four subroutines compute one-dimensional and multi-dimensional Fourier transforms for real data, multi-dimensional complex Fourier transforms, and multi-dimensional sine, cosine and sine-cosine transforms. Subroutines use Cooley-Tukey fast Fourier transform. In all but one-dimensional case, transforms are calculated in up to six dimensions.

Krogh, F. T.

1971-01-01

35

The correlation grid: analysis of synchronous spiking in multi-dimensional spike train data and identification of feasible connection architectures  

Microsoft Academic Search

This paper presents a visualization technique specifically designed to support the analysis of synchronous firings in multiple, simultaneously recorded, spike trains. This technique, called the correlation grid, enables investigators to identify groups of spike trains, where each pair of spike trains has a high probability of generating spikes approximately simultaneously or within a constant time shift. Moreover, the correlation grid

L. Stuart; M. Walter; R. Borisyuk

2005-01-01

36

Multi-dimensional admittance spectroscopy  

NASA Astrophysics Data System (ADS)

We introduce the concept of multi-dimensional admittance spectroscopy capable of characterizing thin-film diode structures in both the (standard) transversal and lateral directions. This extends the capabilities of standard admittance spectroscopy based on the model of leaky capacitor with area defined by the metal contacts. In our approach, the ac signal spreads in the lateral directions far beyond the contact area. The spreading range defines the area of the effective capacitor determining the measured capacitance and conductance. It depends on the ac signal frequency, dc bias, and various structure parameters. A phenomenological description of these dependencies here is verified numerically using our original software to model the distributed admittance via finite element circuits. We analyze the case of photovoltaic devices and show how the multi-dimensional admittance spectroscopy is sensitive to lateral nonuniformity of the system, particularly to the presence of shunts and weak diodes and their location. In addition, the proposed characterization provides information about the system lump parameters, such as sheet resistance, shunt resistance, and open circuit voltage.

Wieland, K.; Vasko, A.; Karpov, V. G.

2013-01-01

37

Accurate, efficient and monotonic numerical methods for multi-dimensional compressible flows. Part II: Multi-dimensional limiting process  

NASA Astrophysics Data System (ADS)

Through the analysis of conventional TVD limiters, a new multi-dimensional limiting function is derived for an oscillation control in multi-dimensional flows. And, multi-dimensional limiting process (MLP) is developed with the multi-dimensional limiting function. The major advantage of MLP is to prevent oscillations across a multi-dimensional discontinuity, and it is readily compatible with more than third order spatial interpolation. Moreover, compared with other higher order interpolation schemes such as ENO type schemes, MLP shows a good convergence characteristic in a steady problem and it is very simple to be implemented. In the present paper, third and fifth order interpolation schemes with MLP, named MLP3 and MLP5, are developed and tested for several real applications. Through extensive numerous test cases including an oblique stationary contact discontinuity, an expansion fan, a vortex flow, a shock wave/vortex interaction and a viscous shock tube problem, it is verified that MLP combined with M-AUSMPW+ numerical flux substantially improves accuracy, efficiency and robustness both in continuous and discontinuous flows. By extending the current approach to three-dimensional flows, MLP is expected to reduce computational cost and enhance accuracy even further.

Kim, Kyu Hong; Kim, Chongam

2005-09-01

38

Scaling discourse analysis: Experiences from Hermanus, South Africa and Walvis Bay, Namibia1  

Microsoft Academic Search

Scaling discourse analysis refers to the necessity to consider environmental discourse a multi-dimensional and diversified practice. Depending on the various levels of state and society at which environmental policies are applied and depending on the geographical scale at which their solution is sought, we have to differentiate both policy processes and outcomes in environmental politics. We introduce the importance of

Roger Keil; Anne-Marie Debbané

2005-01-01

39

Multi-Dimensional Polarized Radiative Transfer: Methods and Solar Applications  

NASA Astrophysics Data System (ADS)

Observations of the Sun using modern telescopes as well as numerical simulations of the Sun reveal existence of enormous inhomogeneous structures in the solar atmosphere. The polarized spectrum of the Sun (Second Solar Spectrum), produced due to anisotropic scattering helps to infer the temperature structure, magnetic fields, and other physical properties of the solar atmosphere more accurately. Analysis of the Second Solar Spectrum requires solution of the polarized radiative transfer equation. To take spatial inhomogeneities into account, a solution of the transfer equation in multi-dimensional geometries is necessary. In this paper we present a specialized review of recent developments in the methods to solve multi-dimensional polarized radiative transfer equation and an application of these methods to analyze the observations.

Anusha, L. S.; Nagendra, K. N.

2014-10-01

40

A new measure of orthogonality for multi-dimensional chromatography.  

PubMed

Multi-dimensional chromatographic techniques, such as (comprehensive) two-dimensional liquid chromatography and (comprehensive) two-dimensional gas chromatography, are increasingly popular for the analysis of complex samples, such as protein digests or mineral oils. The reason behind the popularity of these techniques is the superior performance, in terms of peak-production rate (peak capacity per unit time), that multi-dimensional separations offer compared to their one-dimensional counterparts. However, to fully utilize the potential of multi-dimensional chromatography it is essential that the separation mechanisms used in each dimension be independent of each other. In other words, the two separation mechanisms need to be orthogonal. A number of algorithms have been proposed in the literature for measuring chromatographic orthogonality. However, these methods have their limitations, such as reliance on the division of the separation space into bins, need for specialist software or requirement of advanced programming skills. In addition, some of the existing methods for measuring orthogonality include regions of the separation space that do not feature peaks. In this paper we introduce a number of equations which provides information on the spread of the peaks within the separation space in addition to measuring orthogonality, without the need for complex computations or division of the separation space into bins. PMID:25064248

Camenzuli, Michelle; Schoenmakers, Peter J

2014-08-01

41

Multi-dimensional shock capturing  

NASA Astrophysics Data System (ADS)

The author has worked on two aspects of multidimensional shock capturing. The first project has been a multifaceted effort to understand dynamic liquid-vapor interface propagation from a kinetic point of view. The phenomenon was modeled via a Boltzmann like cluster dynamics model. Clusters represent groupings of molecules of various cluster sizes which can collide elastically and inelastically. The inelastic collisions can produce coagulation of clusters or fragmentation of a cluster. A fluid made of only small cluster sizes would represent a dilute vapor while one containing very large cluster sizes would be a metastable supersaturated vapor. The model via various scaling limits gives sets of equations describing vapor flow in various transition regimes. Numerical experiments were performed modeling vapor to saturated vapor phase change encountered when a dilute vapor encounters a rigid wall.

Slemrod, Marshall

42

The Art of Extracting One-Dimensional Flow Properties from Multi-Dimensional Data Sets  

NASA Technical Reports Server (NTRS)

The engineering design and analysis of air-breathing propulsion systems relies heavily on zero- or one-dimensional properties (e:g: thrust, total pressure recovery, mixing and combustion efficiency, etc.) for figures of merit. The extraction of these parameters from experimental data sets and/or multi-dimensional computational data sets is therefore an important aspect of the design process. A variety of methods exist for extracting performance measures from multi-dimensional data sets. Some of the information contained in the multi-dimensional flow is inevitably lost when any one-dimensionalization technique is applied. Hence, the unique assumptions associated with a given approach may result in one-dimensional properties that are significantly different than those extracted using alternative approaches. The purpose of this effort is to examine some of the more popular methods used for the extraction of performance measures from multi-dimensional data sets, reveal the strengths and weaknesses of each approach, and highlight various numerical issues that result when mapping data from a multi-dimensional space to a space of one dimension.

Baurle, R. A.; Gaffney, R. L.

2007-01-01

43

Continuous Energy, Multi-Dimensional Transport Calculations for Problem Dependent Resonance Self-Shielding  

SciTech Connect

The overall objective of the work here has been to eliminate the approximations used in current resonance treatments by developing continuous energy multi-dimensional transport calculations for problem dependent self-shielding calculations. The work here builds on the existing resonance treatment capabilities in the ORNL SCALE code system.

T. Downar

2009-03-31

44

Methodological Issues in Developing a Multi-Dimensional Coding Procedure for Small-Group Chat Communication  

ERIC Educational Resources Information Center

In CSCL research, collaboration through chat has primarily been studied in dyadic settings. This article discusses three issues that emerged during the development of a multi-dimensional coding procedure for small-group chat communication: (a) the unit of analysis and unit fragmentation, (b) the reconstruction of the response structure and (c)…

Strijbos, Jan-Willem; Stahl, Gerry

2007-01-01

45

Star-ND (Multi-Dimensional Star-Identification)  

E-print Network

In order to perform star-identification with lower processing requirements, multi-dimensional techniques are implemented in this research as a database search as well as to create star pattern parameters. New star pattern parameters are presented...

Spratling, Benjamin

2012-07-16

46

Multi-Dimensional Calibration of Impact Dynamic Models  

NASA Technical Reports Server (NTRS)

NASA Langley, under the Subsonic Rotary Wing Program, recently completed two helicopter tests in support of an in-house effort to study crashworthiness. As part of this effort, work is on-going to investigate model calibration approaches and calibration metrics for impact dynamics models. Model calibration of impact dynamics problems has traditionally assessed model adequacy by comparing time histories from analytical predictions to test at only a few critical locations. Although this approach provides for a direct measure of the model predictive capability, overall system behavior is only qualitatively assessed using full vehicle animations. In order to understand the spatial and temporal relationships of impact loads as they migrate throughout the structure, a more quantitative approach is needed. In this work impact shapes derived from simulated time history data are used to recommend sensor placement and to assess model adequacy using time based metrics and orthogonality multi-dimensional metrics. An approach for model calibration is presented that includes metric definitions, uncertainty bounds, parameter sensitivity, and numerical optimization to estimate parameters to reconcile test with analysis. The process is illustrated using simulated experiment data.

Horta, Lucas G.; Reaves, Mercedes C.; Annett, Martin S.; Jackson, Karen E.

2011-01-01

47

Fast Packet Classification Using Multi-Dimensional Encoding  

NASA Astrophysics Data System (ADS)

Internet routers need to classify incoming packets quickly into flows in order to support features such as Internet security, virtual private networks and Quality of Service (QoS). Packet classification uses information contained in the packet header, and a predefined rule table in the routers. Packet classification of multiple fields is generally a difficult problem. Hence, researchers have proposed various algorithms. This study proposes a multi-dimensional encoding method in which parameters such as the source IP address, destination IP address, source port, destination port and protocol type are placed in a multi-dimensional space. Similar to the previously best known algorithm, i.e., bitmap intersection, multi-dimensional encoding is based on the multi-dimensional range lookup approach, in which rules are divided into several multi-dimensional collision-free rule sets. These sets are then used to form the new coding vector to replace the bit vector of the bitmap intersection algorithm. The average memory storage of this encoding is ? (L · N · log N) for each dimension, where L denotes the number of collision-free rule sets, and N represents the number of rules. The multi-dimensional encoding practically requires much less memory than bitmap intersection algorithm. Additionally, the computation needed for this encoding is as simple as bitmap intersection algorithm. The low memory requirement of the proposed scheme means that it not only decreases the cost of packet classification engine, but also increases the classification performance, since memory represents the performance bottleneck in the packet classification engine implementation using a network processor.

Huang, Chi Jia; Chen, Chien

48

The Multi-Dimensional Demands of Reading in the Disciplines  

ERIC Educational Resources Information Center

This commentary addresses the complexities of reading comprehension with an explicit focus on reading in the disciplines. The author proposes reading as entailing multi-dimensional demands of the reader and posing complex challenges for teachers. These challenges are intensified by restrictive conceptions of relevant prior knowledge and experience…

Lee, Carol D.

2014-01-01

49

Multi dimensional second order defuzzification algorithm (M-SODA)  

Microsoft Academic Search

Multi dimensional second order defuzzification algorithm (SODA) minimizes the hardware requirement and ensures easier implementation of a fuzzy controller as compared to the LUT and the triangular membership approach when extended to multiple dimensions. In this paper we have put forward the extension of the SODA to multiple dimensions. Fuzzy controllers can handle multiple inputs and outputs however size of

Nirav Dharia; J. Gownipalli; B. M. Wilamowski; O. Kaynak

2002-01-01

50

Multi-Dimensional Continuous Metric for Mesh Adaptation  

E-print Network

]. However, only a few of them have dealt with the three-dimensional case [13, 16, 20, 28, 23]. Recently the interpolation error in norm Lp in order to generate anisotropic adapted meshes [26, 6, 5]. Formally speakingMulti-Dimensional Continuous Metric for Mesh Adaptation Fr´ed´eric Alauzet1 , Adrien Loseille1

Frey, Pascal

51

A multi-dimensional constitutive model for shape memory alloys  

Microsoft Academic Search

This paper presents a multi-dimensional thermomechanical constitutive model for shape memory alloys (SMAs). This constitutive relation is based upon a combination of both micromechanics and macromechanics. The martensite fraction is introduced as a variable in this model to reflect the martensitic transformation that determines the unique characteristics of shape memory alloys. This constitutive relation can be used to study the

C. Liang; C. A. Rogers

1992-01-01

52

Factorial LDA: Sparse Multi-Dimensional Text Models  

E-print Network

- pline, and focus (methods vs. applications). Our modeling improvements reduce test perplexity and improve human interpretability of the discovered factors. 1 Introduction There are many factorsFactorial LDA: Sparse Multi-Dimensional Text Models Michael J. Paul and Mark Dredze Human Language

Dredze, Mark

53

Multi-Dimensional Online Tracking Ke Yi Qin Zhang  

E-print Network

give competitive online algorithms whose communication costs are compared with the opti- mal offline.e., the worst-case ratio between the cost of the online algorithm and the cost of the best offline algorithmMulti-Dimensional Online Tracking Ke Yi Qin Zhang Department of Computer Science and Engineering

Yi, Ke "Kevin"

54

Examination of multi-dimensional vibration isolation measures and their correlation to sound radiation over a broad frequency range  

Microsoft Academic Search

This article examines alternate vibration isolation measures for a multi-dimensional system. The isolator and receiver are modelled by the continuous system theory. The source is assumed to be rigid and both force and moment excitations are considered. Our analysis is limited to a linear time-invariant system, and the mobility synthesis method is adopted to describe the overall system behavior. Inverted

Rajendra Singh; Seungbo Kim

2003-01-01

55

Interpolation between multi-dimensional histograms using a new non-linear moment morphing method  

E-print Network

A prescription is presented for the interpolation between multi-dimensional distribution templates based on one or multiple model parameters. The technique uses a linear combination of templates, each created using fixed values of the model's parameters and transformed according to a specific procedure, to model a non-linear dependency on model parameters and the dependency between them. By construction the technique scales well with the number of input templates used, which is a useful feature in modern day particle physics, where a large number of templates is often required to model the impact of systematic uncertainties.

Baak, Max; Harrington, Robert; Verkerke, Wouter

2014-01-01

56

Interpolation between multi-dimensional histograms using a new non-linear moment morphing method  

E-print Network

A prescription is presented for the interpolation between multi-dimensional distribution templates based on one or multiple model parameters. The technique uses a linear combination of templates, each created using fixed values of the model's parameters and transformed according to a specific procedure, to model a non-linear dependency on model parameters and the dependency between them. By construction the technique scales well with the number of input templates used, which is a useful feature in modern day particle physics, where a large number of templates is often required to model the impact of systematic uncertainties.

Max Baak; Stefan Gadatsch; Robert Harrington; Wouter Verkerke

2014-10-27

57

Stationary solutions for multi-dimensional Gross-Pitaevskii equation with double-well potential  

E-print Network

In this paper we consider a non-linear Schroedinger equation with a cubic nonlinearity and a multi-dimensional double well potential. In the semiclassical limit the problem of the existence of stationary solutions simply reduces to the analysis of a finite dimensional Hamiltonian system which exhibits different behavior depending on the dimension. In particular, in dimension 1 the symmetric stationary solution shows a standard pitchfork bifurcation effect, while in dimension 2 and 3 new asymmetrical solutions associated to saddle points occur. These last solutions are localized on a single well and this fact is related to the phase transition effect observed in Bose-Einstein condensates in periodical lattices.

Andrea Sacchetti

2013-12-04

58

Stationary solutions to the multi-dimensional Gross–Pitaevskii equation with double-well potential  

NASA Astrophysics Data System (ADS)

In this paper we consider a nonlinear Schrödinger equation with a cubic nonlinearity and a multi-dimensional double well potential. In the semiclassical limit the problem of the existence of stationary solutions simply reduces to the analysis of a finite dimensional Hamiltonian system which exhibits different behaviour depending on the dimension. In particular, in dimension 1 the symmetric stationary solution shows a standard pitchfork bifurcation effect, while in dimensions 2 and 3 new asymmetrical solutions associated with saddle points occur. These last solutions are localized on a single well and this fact is related to the phase transition effect observed in Bose–Einstein condensates in periodical lattices.

Sacchetti, Andrea

2014-11-01

59

Recent Advances in Fragment-Based QSAR and Multi-Dimensional QSAR Methods  

PubMed Central

This paper provides an overview of recently developed two dimensional (2D) fragment-based QSAR methods as well as other multi-dimensional approaches. In particular, we present recent fragment-based QSAR methods such as fragment-similarity-based QSAR (FS-QSAR), fragment-based QSAR (FB-QSAR), Hologram QSAR (HQSAR), and top priority fragment QSAR in addition to 3D- and nD-QSAR methods such as comparative molecular field analysis (CoMFA), comparative molecular similarity analysis (CoMSIA), Topomer CoMFA, self-organizing molecular field analysis (SOMFA), comparative molecular moment analysis (COMMA), autocorrelation of molecular surfaces properties (AMSP), weighted holistic invariant molecular (WHIM) descriptor-based QSAR (WHIM), grid-independent descriptors (GRIND)-based QSAR, 4D-QSAR, 5D-QSAR and 6D-QSAR methods. PMID:21152304

Myint, Kyaw Zeyar; Xie, Xiang-Qun

2010-01-01

60

A Multi-Dimensional Instrument for Evaluating Taiwanese High School Students' Science Learning Self-Efficacy in Relation to Their Approaches to Learning Science  

ERIC Educational Resources Information Center

In the past, students' science learning self-efficacy (SLSE) was usually measured by questionnaires that consisted of only a single scale, which might be insufficient to fully understand their SLSE. In this study, a multi-dimensional instrument, the SLSE instrument, was developed and validated to assess students' SLSE based on the…

Lin, Tzung-Jin; Tsai, Chin-Chung

2013-01-01

61

Advanced multi-dimensional method for structural and hydrodynamic analyses of LMFBR piping systems  

SciTech Connect

Maintaining the structural integrity of the piping system of Liquid Metal Fast Breeder Reactors (LMFBRs) is essential to the safe operation of the reactor and steam supply systems. In the safety analysis various transient loads can be imposed on the piping systems, which may pose threats to the integrity of the piping structure. These transient loads can be classified into two categories. The first represents dynamic loads resulting from the hydrodynamic pressure-wave propagation or seismic events. The second represents static or quasi-dynamic loads generated by thermal wave propagation, normal operation transient, or creep phenomena. At Argonne National Laboratory, a multi-dimensional method has been developed for the integrated analysis of piping systems under these transient loading conditions. It utilizes a 2-D implicit finite-difference hydrodynamics in conjunction with a 3-D explicit finite-element structural analysis.

Wang, C.Y.; Zeuch, W.R.

1985-04-09

62

The evolution of anisotropic structures and turbulence in the multi-dimensional Burgers equation  

E-print Network

The goal of the present paper is the investigation of the evolution of anisotropic regular structures and turbulence at large Reynolds number in the multi-dimensional Burgers equation. We show that we have local isotropization of the velocity and potential fields at small scale inside cellular zones. For periodic waves, we have simple decay inside of a frozen structure. The global structure at large times is determined by the initial correlations, and for short range correlated field, we have isotropization of turbulence. The other limit we consider is the final behavior of the field, when the processes of nonlinear and harmonic interactions are frozen, and the evolution of the field is determined only by the linear dissipation.

S. N. Gurbatov; A. Yu. Moshkov; A. Noullez

2008-08-20

63

On Multi-Dimensional Vocabulary Teaching Mode for College English Teaching  

ERIC Educational Resources Information Center

This paper analyses the major approaches in EFL (English as a Foreign Language) vocabulary teaching from historical perspective and puts forward multi-dimensional vocabulary teaching mode for college English. The author stresses that multi-dimensional approaches of communicative vocabulary teaching, lexical phrase teaching method, the grammar…

Zhou, Li-na

2010-01-01

64

Scaling analysis of transient heating  

NSDL National Science Digital Library

This problem is a simple case designed to show the power of scaling analysis to estimate the behavior of variables of interest without doing a detailed analysis. Here, internal heat generation heats a square part and the student is asked to find the dependence of the maximum temperature on time. The use of a scaling analysis encourages the student to think about the physics of the problem more than just solving the differential equation.

Krane, Matthew J.

2008-10-14

65

A decomposition method with minimum communication amount for parallelization of multi-dimensional FFTs  

NASA Astrophysics Data System (ADS)

The fast Fourier transform (FFT) is undoubtedly an essential primitive that has been applied in various fields of science and engineering. In this paper, we present a decomposition method for the parallelization of multi-dimensional FFTs with the smallest communication amounts for all ranges of the number of processes compared to previously proposed methods. This is achieved by two distinguishing features: adaptive decomposition and transpose order awareness. In the proposed method, the FFT data is decomposed based on a row-wise basis that maps the multi-dimensional data into one-dimensional data, and translates the corresponding coordinates from multi-dimensions into one dimension so that the one-dimensional data can be divided and allocated equally to the processes using a block distribution. As a result and different from previous works that have the dimensions of decomposition pre-defined, our method can adaptively decompose the FFT data on the lowest possible dimensions depending on the number of processes. In addition, this row-wise decomposition provides plenty of alternatives in data transpose, and different transpose order results in different amounts of communication. We identify the best transpose orders with the smallest communication amounts for the 3-D, 4-D, and 5-D FFTs by analyzing all possible cases. We also develop a general parallel software package for the most popular 3-D FFT based on our method using the 2-D domain decomposition. Numerical results show good performance and scaling properties of our implementation in comparison with other parallel packages. Given both communication efficiency and scalability, our method is promising in the development of highly efficient parallel packages for the FFT.

Duy, Truong Vinh Truong; Ozaki, Taisuke

2014-01-01

66

Entanglement Entropy of Fermi Liquids via Multi-dimensional Bosonization  

NASA Astrophysics Data System (ADS)

The logarithmic violations of the area law, i.e. an ``area law'' with logarithmic correction of the form S ˜L^d-1 L, for entanglement entropy are found in both 1D gapless system and for high dimensional free fermions. The purpose of this work is to show that both violations are of the same origin, and in the presence of Fermi liquid interactions such behavior persists for 2D fermion systems. In this paper we first consider the entanglement entropy of a toy model, namely a set of decoupled 1D chains of free spinless fermions, to relate both violations in an intuitive way. We then use multi-dimensional bosonization to re-derive the formula by Gioev and Klich [Phys. Rev. Lett. 96, 100503 (2006)] for free fermions through a low-energy effective Hamiltonian, and explicitly show the logarithmic corrections to the area law in both cases share the same origin: the discontinuity at the Fermi surface (points). In the presence of Fermi liquid (forward scattering) interactions, the bosonized theory remains quadratic in terms of the original local degrees of freedom, and after regularizing the theory with a mass term we are able to calculate the entanglement entropy perturbatively up to second order in powers of the coupling parameter for a special geometry via the replica trick.

Ding, Wenxin; Seidel, Alexander; Yang, Kun

2012-02-01

67

A global inversion method for multi-dimensional NMR logging.  

PubMed

We describe a general global inversion methodology of multi-dimensional NMR logging for pore fluid typing and quantification in petroleum exploration. Although higher dimensions are theoretically possible, for practical reasons, we limit our discussion of proton density distributions as a function of two (2D) or three (3D) independent variables. The 2D can be diffusion coefficient and T(2) relaxation time (D-T(2)), and the 3D can be diffusion coefficient, T(2), and T(1) relaxation times (D-T(2)-T(1)) of the saturating fluids in rocks. Using the contrast between the diffusion coefficients of fluids (oil and water), the oil and water phases within the rocks can be clearly identified. This 2D or 3D proton density distribution function can be obtained from either two-window or regular type multiple CPMG echo trains encoded with diffusion, T(1), and T(2) relaxation by varying echo spacing and wait time. From this 2D/3D proton density distribution function, not only the saturations of water and oil can be determined, the viscosity of the oil and the gas-oil ratio can also be estimated based on a previously experimentally determined D-T(2) relationship. PMID:15589418

Sun, Boqin; Dunn, Keh-Jim

2005-01-01

68

Surface extraction from multi-field particle volume data using multi-dimensional cluster visualization.  

PubMed

Data sets resulting from physical simulations typically contain a multitude of physical variables. It is, therefore, desirable that visualization methods take into account the entire multi-field volume data rather than concentrating on one variable. We present a visualization approach based on surface extraction from multi-field particle volume data. The surfaces segment the data with respect to the underlying multi-variate function. Decisions on segmentation properties are based on the analysis of the multi-dimensional feature space. The feature space exploration is performed by an automated multi-dimensional hierarchical clustering method, whose resulting density clusters are shown in the form of density level sets in a 3D star coordinate layout. In the star coordinate layout, the user can select clusters of interest. A selected cluster in feature space corresponds to a segmenting surface in object space. Based on the segmentation property induced by the cluster membership, we extract a surface from the volume data. Our driving applications are Smoothed Particle Hydrodynamics (SPH) simulations, where each particle carries multiple properties. The data sets are given in the form of unstructured point-based volume data. We directly extract our surfaces from such data without prior resampling or grid generation. The surface extraction computes individual points on the surface, which is supported by an efficient neighborhood computation. The extracted surface points are rendered using point-based rendering operations. Our approach combines methods in scientific visualization for object-space operations with methods in information visualization for feature-space operations. PMID:18989000

Linsen, Lars; Van Long, Tran; Rosenthal, Paul; Rosswog, Stephan

2008-01-01

69

An Efficient Multi-Dimensional Index for Cloud Data Xiangyu Zhang, Jing Ai, Zhongyuan Wang, Jiaheng Lu, Xiaofeng Meng  

E-print Network

process typ- ical multi-dimensional queries including point queries and range queries efficiently. Besides Management]: Systems--concurrency, transaction processing General Terms Algorithms Keywords multi-dimensionalAn Efficient Multi-Dimensional Index for Cloud Data Management Xiangyu Zhang, Jing Ai, Zhongyuan

70

Accessing Multi-Dimensional Images and Data Cubes in the Virtual Observatory  

NASA Astrophysics Data System (ADS)

Telescopes across the spectrum are routinely producing multi-dimensional images and datasets, such as Doppler velocity cubes, polarization datasets, and time-resolved “movies.” Examples of current telescopes producing such multi-dimensional images include the JVLA, ALMA, and the IFU instruments on large optical and near-infrared wavelength telescopes. In the near future, both the LSST and JWST will also produce such multi-dimensional images routinely. High-energy instruments such as Chandra produce event datasets that are also a form of multi-dimensional data, in effect being a very sparse multi-dimensional image. Ensuring that the data sets produced by these telescopes can be both discovered and accessed by the community is essential and is part of the mission of the Virtual Observatory (VO). The Virtual Astronomical Observatory (VAO, http://www.usvao.org/), in conjunction with its international partners in the International Virtual Observatory Alliance (IVOA), has developed a protocol and an initial demonstration service designed for the publication, discovery, and access of arbitrarily large multi-dimensional images. The protocol describing multi-dimensional images is the Simple Image Access Protocol, version 2, which provides the minimal set of metadata required to characterize a multi-dimensional image for its discovery and access. A companion Image Data Model formally defines the semantics and structure of multi-dimensional images independently of how they are serialized, while providing capabilities such as support for sparse data that are essential to deal effectively with large cubes. A prototype data access service has been deployed and tested, using a suite of multi-dimensional images from a variety of telescopes. The prototype has demonstrated the capability to discover and remotely access multi-dimensional data via standard VO protocols. The prototype informs the specification of a protocol that will be submitted to the IVOA for approval, with an operational data cube service to be delivered in mid-2014. An associated user-installable VO data service framework will provide the capabilities required to publish VO-compatible multi-dimensional images or data cubes.

Tody, Douglas; Plante, R. L.; Berriman, G. B.; Cresitello-Dittmar, M.; Good, J.; Graham, M.; Greene, G.; Hanisch, R. J.; Jenness, T.; Lazio, J.; Norris, P.; Pevunova, O.; Rots, A. H.

2014-01-01

71

Chemistry and Transport in a Multi-Dimensional Model  

NASA Technical Reports Server (NTRS)

Our work has two primary scientific goals, the interannual variability (IAV) of stratospheric ozone and the hydrological cycle of the upper troposphere and lower stratosphere. Our efforts are aimed at integrating new information obtained by spacecraft and aircraft measurements to achieve a better understanding of the chemical and dynamical processes that are needed for realistic evaluations of human impact on the global environment. A primary motivation for studying the ozone layer is to separate the anthropogenic perturbations of the ozone layer from natural variability. Using the recently available merged ozone data (MOD), we have carried out an empirical orthogonal function EOF) study of the temporal and spatial patterns of the IAV of total column ozone in the tropics. The outstanding problem about water in the stratosphere is its secular increase in the last few decades. The Caltech/PL multi-dimensional chemical transport model (CTM) photochemical model is used to simulate the processes that control the water vapor and its isotopic composition in the stratosphere. Datasets we will use for comparison with model results include those obtained by the Total Ozone Mapping Spectrometer (TOMS), the Solar Backscatter Ultraviolet (SBUV and SBUV/2), Stratosphere Aerosol and Gas Experiment (SAGE I and II), the Halogen Occultation Experiment (HALOE), the Atmospheric Trace Molecular Spectroscopy (ATMOS) and those soon to be obtained by the Cirrus Regional Study of Tropical Anvils and Cirrus Layers Florida Area Cirrus Experiment (CRYSTAL-FACE) mission. The focus of the investigations is the exchange between the stratosphere and the troposphere, and between the troposphere and the biosphere.

Yung, Yuk L.

2004-01-01

72

Multi-dimensional Multiphase Modeling of Sediment Transport  

NASA Astrophysics Data System (ADS)

Sediment transport driven by waves and currents is of great significance to further predict coastal morphodynamics. Eulerian two-phase models have been shown effective to study sheet flow sediment transport, though most of them are limited to Reynolds-averaged one-dimensional-vertical formulation. Hence, bedform, plug flow and turbulence cannot be resolved. Our goal is to develop four-way coupled multiphase models for multi-dimensional sediment transport under the numerical framework of OpenFOAM for Eulerian modeling and CFDEM for Euler-Lagrangian modeling. In the Eulerian modeling, particle-particle interaction is modeled using the kinetic theory for granular flow for binary collision and phenomenological closure for stresses of enduring contact. To improve the capability of the model for a range of grain sizes, a new closure for the fluid-particle velocity fluctuation correlation in the k-? equations is proposed. The model is validated by comparing the numerical results with laboratory experiments under steady flow and oscillatory flow for grain size ranging from 0.13~0.51 mm. To improve the closure of particle stress and studying poly-dispersed sediment transport processes, an Euler-Lagrangian solver called CFDEM, which couples OpenFOAM for the fluid phase and LIGGGHTS for particle phase, is modified for sand transport in oscillatory flow. Preliminary investigation suggests that even under sheet flow condition, small bed irregularities are observed during flow reversal. These small irregularities later encourage the formation of large sediment cloud during peak flow. 2D/3D simulation of the recent U-tube experiments at Naval Research Laboratory will be carried out to study instabilities in sheet flow and the poly-dispersed effects.

Cheng, Z.; d'Albignac, S.; Yu, X.; Hsu, T.; Sou, I.; Calantoni, J.

2012-12-01

73

Multi-dimensional ultra-high frequency passive radio frequency identification tag antenna designs  

E-print Network

In this thesis, we present the design, simulation, and empirical evaluation of two novel multi-dimensional ultra-high frequency (UHF) passive radio frequency identification (RFID) tag antennas, the Albano-Dipole antenna ...

Delichatsios, Stefanie Alkistis

2006-01-01

74

Toward a Multi-Dimensional Measure of Clustering in Free Recall.  

ERIC Educational Resources Information Center

Various reported measures of clustering in free recall are reviewed under categories of algebraic versus probabilistic approaches. Shortcomings in these measures are outlined and a new multi-dimensional measure is advanced which overcomes many of the deficiencies noted. (Author)

Schmuller, Joseph A.; Farley, Frank H.

75

Assortativity Patterns in Multi-dimensional Inter-organizational Networks: A Case Study of the Humanitarian Relief Sector  

NASA Astrophysics Data System (ADS)

We use computational tools to study assortativity patterns in multi-dimensional inter-organizational networks on the basis of different node attributes. In the case study of an inter-organizational network in the humanitarian relief sector, we consider not only macro-level topological patterns, but also assortativity on the basis of micro-level organizational attributes. Unlike assortative social networks, this inter-organizational network exhibits disassortative or random patterns on three node attributes. We believe organizations' seek of complementarity is one of the main reasons for the special patterns. Our analysis also provides insights on how to promote collaborations among the humanitarian relief organizations.

Zhao, Kang; Ngamassi, Louis-Marie; Yen, John; Maitland, Carleen; Tapia, Andrea

76

Assessing an academic library collection through capacity and usage indicators: testing a multi-dimensional model  

Microsoft Academic Search

Purpose – The purpose of this paper is to test a multi-dimensional model of indicators for collection evaluation (proposed in a previous paper by the authors) and to illustrate how to apply these indicators in practice. Design\\/methodology\\/approach – An analytical study will be used to test the use of the multi-dimensional collection evaluation model to assess an academic library collection.

Jacqueline Borin; Hua Yi

2011-01-01

77

Pricing of options on stocks driven by multi-dimensional operator stable Levy processes  

E-print Network

We model the price of a stock via a Lang\\'{e}vin equation with multi-dimensional fluctuations coupled in the price and in time. We generalize previous models in that we assume that the fluctuations conditioned on the time step are compound Poisson processes with operator stable jump intensities. We derive exact relations for Fourier transforms of the jump intensity in case of different scaling indices $\\underline{\\underline{E}}$ of the process. We express the Fourier transform of the joint probability density of the process to attain given values at several different times and to attain a given maximal value in a given time period through Fourier transforms of the jump intensity. Then we consider a portfolio composed of stocks and of options on stocks and we derive the Fourier transform of a random variable $\\mathfrak{D}_t$ (deviation of the portfolio) that is defined as a small temporal change of the portfolio diminished by the the compound interest earned. We show that if the price of the option at time $t$ satisfies a certain functional equation specified in text then the deviation of the portfolio has a zero mean $E[ \\mathfrak{D}_t ] = 0$ and the option pricing problem may have a solution. We compare our approach to other approaches that assumed the log-characteristic function of the fluctuations that drive the stock price to be an analytic function.

Przemyslaw Repetowicz; Peter Richmond

2004-12-20

78

Accurate numerical schemes based on the lattice Boltzmann methods for multi-dimensional diffusion equations  

NASA Astrophysics Data System (ADS)

We propose accurate explicit numerical schemes based on the lattice Boltzmann (LB) method for multi-dimensional diffusion equations. In LB schemes, the velocity models D2Q9 and D2Q13 are used for two-dimensional equations and D3Q19 and D3Q25 for three-dimensional equations. We introduce free parameters that characterize the weight of the equilibrium distribution functions to reduce numerical errors. Consistency analysis through the fourth-order Chapman-Ensgok expansion of the distribution functions gives an approximate diffusion equation with error terms up to fourth-order. The relaxation parameter and weight parameters are determined so that second-order error terms are eliminated in the approximate equation. Stability analysis shows that we can find a relaxation parameter so that each of the presented schemes is stable for given diffusion coefficients and discretizing parameters. Numerical experiments for the isotropic and anisotropic benchmark problems show that the presented schemes derived from the velocity models D2Q13 and D3Q25 are useful for numerical simulations of practical problems governed by two- and three-dimensional diffusion equations, respectively. In particular, schemes in which the value of the relaxation parameter is set to be 1 demonstrate a fourth-order accuracy under the stability condition.

Suga, Shinsuke

2014-11-01

79

Scaling analysis of stock markets  

NASA Astrophysics Data System (ADS)

In this paper, we apply the detrended fluctuation analysis (DFA), local scaling detrended fluctuation analysis (LSDFA), and detrended cross-correlation analysis (DCCA) to investigate correlations of several stock markets. DFA method is for the detection of long-range correlations used in time series. LSDFA method is to show more local properties by using local scale exponents. DCCA method is a developed method to quantify the cross-correlation of two non-stationary time series. We report the results of auto-correlation and cross-correlation behaviors in three western countries and three Chinese stock markets in periods 2004-2006 (before the global financial crisis), 2007-2009 (during the global financial crisis), and 2010-2012 (after the global financial crisis) by using DFA, LSDFA, and DCCA method. The findings are that correlations of stocks are influenced by the economic systems of different countries and the financial crisis. The results indicate that there are stronger auto-correlations in Chinese stocks than western stocks in any period and stronger auto-correlations after the global financial crisis for every stock except Shen Cheng; The LSDFA shows more comprehensive and detailed features than traditional DFA method and the integration of China and the world in economy after the global financial crisis; When it turns to cross-correlations, it shows different properties for six stock markets, while for three Chinese stocks, it reaches the weakest cross-correlations during the global financial crisis.

Bu, Luping; Shang, Pengjian

2014-06-01

80

Scaling analysis of stock markets.  

PubMed

In this paper, we apply the detrended fluctuation analysis (DFA), local scaling detrended fluctuation analysis (LSDFA), and detrended cross-correlation analysis (DCCA) to investigate correlations of several stock markets. DFA method is for the detection of long-range correlations used in time series. LSDFA method is to show more local properties by using local scale exponents. DCCA method is a developed method to quantify the cross-correlation of two non-stationary time series. We report the results of auto-correlation and cross-correlation behaviors in three western countries and three Chinese stock markets in periods 2004-2006 (before the global financial crisis), 2007-2009 (during the global financial crisis), and 2010-2012 (after the global financial crisis) by using DFA, LSDFA, and DCCA method. The findings are that correlations of stocks are influenced by the economic systems of different countries and the financial crisis. The results indicate that there are stronger auto-correlations in Chinese stocks than western stocks in any period and stronger auto-correlations after the global financial crisis for every stock except Shen Cheng; The LSDFA shows more comprehensive and detailed features than traditional DFA method and the integration of China and the world in economy after the global financial crisis; When it turns to cross-correlations, it shows different properties for six stock markets, while for three Chinese stocks, it reaches the weakest cross-correlations during the global financial crisis. PMID:24985421

Bu, Luping; Shang, Pengjian

2014-06-01

81

Partitioning multi-dimensional sets in a small number of "uniform" parts  

E-print Network

Partitioning multi-dimensional sets in a small number of "uniform" parts Noga Alon Ilan Newman, . . . , n} = [n] Schools of Mathematics and Computer Science, Tel Aviv University, Tel Aviv 69978, Israel and Institute for Advanced Study, Princeton, NJ 08540, USA. Email: no- gaa@tau.ac.il. Research supported in part

Shamir, Ron

82

CRITICAL THRESHOLDS IN MULTI-DIMENSIONAL EULER-POISSON EQUATIONS WITH RADIAL SYMMETRY  

E-print Network

CRITICAL THRESHOLDS IN MULTI-DIMENSIONAL EULER-POISSON EQUATIONS WITH RADIAL SYMMETRY DONGMING WEI depends on whether the initial configuration crosses an initial critical thresh- olds in configuration threshold F. Similarly, we characterize the critical threshold for global smooth solutions subject to two

Milchberg, Howard

83

Dominant Color Extraction based on Dynamic Clustering by Multi-Dimensional Particle Swarm Optimization  

E-print Network

of color patterns. One observation worth mentioning here is that the human eye cannot perceive a largeDominant Color Extraction based on Dynamic Clustering by Multi-Dimensional Particle Swarm University of Technology, Tampere, Finland {serkan.kiranyaz, stefan.uhlmann, moncef.gabbouj}@tut.fi Abstract--Color

Gabbouj, Moncef

84

Extracting Multi-Dimensional Signal Features for Content-Based Visual Query  

E-print Network

Visual Information Systems (VIS) to manage and process these visual data is required. EffectiveP-1 Extracting Multi-Dimensional Signal Features for Content-Based Visual Query ABSTRACT Future large visual information systems (such as image databases and video servers) require effective

Chang, Shih-Fu

85

Developing Multi-Dimensional Evaluation Criteria for English Learning Websites with University Students and Professors  

ERIC Educational Resources Information Center

Many English learning websites have been developed worldwide, but little research has been conducted concerning the development of comprehensive evaluation criteria. The main purpose of this study is thus to construct a multi-dimensional set of criteria to help learners and teachers evaluate the quality of English learning websites. These…

Liu, Gi-Zen; Liu, Zih-Hui; Hwang, Gwo-Jen

2011-01-01

86

Measurement of Low Level Explosives Reaction in Gauged MultiDimensional Steven Impact Tests  

Microsoft Academic Search

The Steven Test was developed to determine relative impact sensitivity of metal encased solid high explosives and be amenable to two-dimensional modeling. Low level reaction thresholds occur at impact velocities below those required for shock initiation. To assist in understanding this test, multi-dimensional gauge techniques utilizing carbon foil and carbon resistor gauges were used to measure pressure and event times.

A. M. Niles; J. W. Forbes; C. M. Tarver; S. K. Chidester; F. Garcia; D. W. Greenwood; R. G. Garza; L L Swizter

2001-01-01

87

A combined discontinuous Galerkin and finite volume scheme for multi-dimensional VPFP system  

SciTech Connect

We construct a numerical scheme for the multi-dimensional Vlasov-Poisson-Fokker-Planck system based on a combined finite volume (FV) method for the Poisson equation in spatial domain and the streamline diffusion (SD) and discontinuous Galerkin (DG) finite element in time, phase-space variables for the Vlasov-Fokker-Planck equation.

Asadzadeh, M.; Bartoszek, K. [Department of Mathematics, Chalmers University of Technology and University of Gothenburg SE-412 96 Goeteborg (Sweden)

2011-05-20

88

Multi-dimensional differential imaging with FE-CARS microscopy Vishnu Vardhan Krishnamachari, Eric Olaf Potma *  

E-print Network

Multi-dimensional differential imaging with FE-CARS microscopy Vishnu Vardhan Krishnamachari, Eric-Stokes Raman scattering (CARS) microscopy [9­11], provide high resolu- tion images with contrast based to CARS microscopy and was shown to add a series of new contrast mechanisms to the existing palette

Potma, Eric Olaf

89

Multi-dimensional reduction using self-organizing map  

NASA Astrophysics Data System (ADS)

Self-Organising Map (SOM) is found to be a useful tool for climatological synoptic, analysis in extreme and rainfall pattern, cloud classification and climate change analysis. In data preprocessing for use in statistical downscaling, Principal Component Analysis (PCA) or empirical orthogonal function (EOF) analysis is used to select the mode criterion for the predictor and predictand fields for building a model. However, EOF contributes less total variance for most cases of which 70% to 90% of total population variance is accounted in the analysis. Therefore, SOM is proposed to obtain a nonlinear mapping for the preprocessing process. This study examines the dimension reduction of NCEP variable using SOM during the periods of November-December-January-February (NDJF). The NCEP data used is the 20 grids point atmospheric data for variable Sea Level Pressure (SLP). The result showed that SOM had extracted the high dimensional data onto a low dimensional representation.

Kim, Kho Pui; Yusof, Fadhilah; Daud, Zalina binti Mohd

2014-07-01

90

Multi-scale Analysis with Python  

NASA Astrophysics Data System (ADS)

This talk will discuss the SphereBlur package, written in Python and available in the Ultra-scale Visualization Climate Data AnalysisTools (UV-CDAT) environment. SphereBlur provides a flexible multi-scale analysis toolkit for climate data based on linear scale space. Scale space methods, common in image processing, draw upon the well-studied physics of diffusion to obtain a multi-scale representation of data. A simple extension of these methods to the sphere provides flexible analysis tools for climate data. We use this framework to evaluate model performance at multiple spatial scales and to design filters to isolate scales of interest. We show how these methods can be used to simultaneously detect points and scales of interest in data, and to track the appearance and evolution of features such as corners, edges, and "blobs" in observational and model data. Prepared by LLNL under Contract DE-AC52-07NA27344.

Marvel, K. D.

2012-12-01

91

Multi-dimensional Simulations of Helium Shell Flash Convection  

NASA Astrophysics Data System (ADS)

The Asymptotic Giant Branch (AGB) phase is the most productive evolutionary phase in terms of nucleosynthesis for low and intermediate mass stars. Nucleosythesis in these stars is aided by the mixing and heating triggered by recurrent He-shell flashes. Extreme nuclear energies (corresponding to 10^8L_sun) are generated during these thermonuclear flashes. This results in efficient shell convection with multiple implications for nucleosynthesis and further evolution. The evolution of AGB stars, including these He-flashes, has in the past been studied exclusively with one-dimensional stellar evolution codes that have to adopt simplifying assumptions on mixing, especially at convective boundaries. Here, we report on efforts to augment these studies with 2-d and 3-d hydrodynamic models of convective mixing in the AGB He-shell. We characterize the dominant morphology of He-shell flash convection. As opposed to the shallow surface convection in A-type stars studied by Freytag et al. (1996), coherently moving convective cells do not cross the convective boundary significantly. In other words, penetration is minimal for this convection zone. We find that convective motions induce a rich spectrum of internal gravity waves in the neighboring stable layers. Interactions of these (mainly horizontal) oscillations with the convective boundary, as well as oscillations with convective characteristics within the stable layers, do cause a finite amount of mixing across the convective boundary. Our preliminary analysis of this mixing is consistent with semi-analytical results obtained from observations and 1D-stellar evolution simulations.

Hueckstaedt, Robert M.; Freytag, B.; Herwig, F.; Timmes, F.

2006-12-01

92

Rasch rating scale analysis of the Attitudes Toward Research Scale.  

PubMed

College students may view research methods courses with negative attitudes, however, few studies have investigated this issue due to the lack of instruments that measure the students' attitudes towards research. Therefore, the purpose of this study was to examine the psychometric properties of a Attitudes Toward Research Scale using Rasch rating scale analysis. Assessment of attitudes toward research is essential to determine if students have negative attitudes towards research and assist instructors in better facilitation of learning research methods in their courses. The results of this study have shown that a thirty item Attitudes Toward Research Scale yielded scores with high person and item reliability. PMID:24950536

Papanastasiou, Elena C; Schumacker, Randall

2014-01-01

93

A volume-based multi-dimensional population balance approach for modelling high shear granulation  

Microsoft Academic Search

A volume-based multi-dimensional population balance model based on the approach used by Verkoeijen et al. [2002. Population balances for particulate processes—a volume approach. Chemical Engineering Science 57, 2287–2303], is further developed and applied to a wet granulation process of pharmaceutically relevant material, performed in a high shear mixer. The model is improved by a generalization that accounts for initial non-uniformly

Anders Darelius; Henric Brage; Anders Rasmuson; Ingela Niklasson Björn; Staffan Folestad

2006-01-01

94

Locating the Issue Public: The MultiDimensional Nature of Engagement with Health Care Reform  

Microsoft Academic Search

This research examines in detail the structure of the issue public for health care reform, drawing from extensive, nationally\\u000a representative survey data tapping general attentiveness to news and public affairs, specific interests in health care issues,\\u000a and motivations (e.g., personal health and financial conditions) to follow health care reform issues. We furthermore adopt\\u000a a multi-dimensional approach to defining the contours

Vincent Price; Clarissa David; Brian Goldthorpe; Marci McCoy Roth; Joseph N. Cappella

2006-01-01

95

Spectral Localization by Gaussian Random Potentials in MultiDimensional Continuous Space  

Microsoft Academic Search

A detailed mathematical proof is given that the energy spectrum of a non-relativistic quantum particle in multi-dimensional Euclidean space under the influence of suitable random potentials has almost surely a pure-point component. The result applies in particular to a certain class of zero-mean Gaussian random potentials, which are homogeneous with respect to Euclidean translations. More precisely, for these Gaussian random

Werner Fischer; Hajo Leschke; Peter Müller

2000-01-01

96

Metarule-Guided Mining of MultiDimensional Association Rules Using Data Cubes  

Microsoft Academic Search

In this paper, we employ a novel approach to metarule-guided, multi-dimensional association rule mining which explores a data cube structure. We propose algorithms for metarule-guided min- ing: given a metarule containing p predicates, we compare mining on an n-dimensional (n-D) cube structure (where p < n) with mining on smaller multiple pdimensional cubes. In addition, we propose an efficient method

Micheline Kamber; Jiawei Han; Jenny Chiang

1997-01-01

97

Beyond the Child-Langmuir Law: The Physics of Multi-dimensional Space-Charge-Limited Emission  

NASA Astrophysics Data System (ADS)

Space-Charge-Limited (SCL) flows in diodes have been an area of active research since the pioneering work of Child and Langmuir in the early part of this century. Indeed, the scaling of current density with the voltage to the 3/2s power is one of the best-known limits in the fields of non-neutral plasma physics, accelerator physics, sheath physics, vacuum electronics, and high power microwaves (HPM). In the past five years, there has been renewed interest in the physics and characteristics of space-charge-limited emission in physically realizable configurations. This research has focused on characterizing the current and current density enhancement possible from two- and three-dimensional geometries, such as field-emitting arrays. In 1996, computational efforts led to the development of a scaling law that described the increased current drawn due to two-dimensional effects. Recently, this scaling has been analytically derived from first principles. In parallel efforts, computational work has characterized the edge enhancement of the current density, leading to a better understanding of the physics of explosive emission cathodes. In this talk, the analytic and computational extensions to the one-dimensional Child-Langmuir law will be reviewed, the accuracy of SCL emission algorithms will be assessed, and the experimental implications of multi-dimensional SCL flows will be discussed.

Luginsland, John

2001-10-01

98

Study on the construction of multi-dimensional Remote Sensing feature space for hydrological drought  

NASA Astrophysics Data System (ADS)

Hydrological drought refers to an abnormal water shortage caused by precipitation and surface water shortages or a groundwater imbalance. Hydrological drought is reflected in a drop of surface water, decrease of vegetation productivity, increase of temperature difference between day and night and so on. Remote sensing permits the observation of surface water, vegetation, temperature and other information from a macro perspective. This paper analyzes the correlation relationship and differentiation of both remote sensing and surface measured indicators, after the selection and extraction a series of representative remote sensing characteristic parameters according to the spectral characterization of surface features in remote sensing imagery, such as vegetation index, surface temperature and surface water from HJ-1A/B CCD/IRS data. Finally, multi-dimensional remote sensing features such as hydrological drought are built on a intelligent collaborative model. Further, for the Dong-ting lake area, two drought events are analyzed for verification of multi-dimensional features using remote sensing data with different phases and field observation data. The experiments results proved that multi-dimensional features are a good method for hydrological drought.

Xiang, Daxiang; Tan, Debao; Cui, Yuanlai; Wen, Xiongfei; Shen, Shaohong; Li, Zhe

2014-03-01

99

Scaling analysis of affinity propagation  

Microsoft Academic Search

We analyze and exploit some scaling properties of the affinity propagation (AP) clustering algorithm proposed by Frey and Dueck [Science 315, 972 (2007)]. Following a divide and conquer strategy we setup an exact renormalization-based approach to address the question of clustering consistency, in particular, how many cluster are present in a given data set. We first observe that the divide

Cyril Furtlehner; Michèle Sebag; Xiangliang Zhang

2010-01-01

100

Genuinely multi-dimensional explicit and implicit generalized Shapiro filters for weather forecasting, computational fluid dynamics and aeroacoustics  

NASA Astrophysics Data System (ADS)

This paper addresses the extension of one-dimensional filters in two and three space dimensions. A new multi-dimensional extension is proposed for explicit and implicit generalized Shapiro filters. We introduce a definition of explicit and implicit generalized Shapiro filters that leads to very simple formulas for the analyses in two and three space dimensions. We show that many filters used for weather forecasting, high-order aerodynamic and aeroacoustic computations match the proposed definition. Consequently the new multi-dimensional extension can be easily implemented in existing solvers. The new multi-dimensional extension and the two commonly used methods are compared in terms of compactness, robustness, accuracy and computational cost. Benefits of the genuinely multi-dimensional extension are assessed for various computations using the compressible Euler equations.

Falissard, F.

2013-11-01

101

Experimental investigation on multi-dimensional digital predistortion for multi-band radio-over-fiber systems.  

PubMed

The recently-proposed multi-dimensional digital predistortion (DPD) technique is experimentally investigated in terms of nonlinearity order, memory length, oversampling rate, digital-to-analog conversion resolution, carrier frequency dependence and RF input power tolerance, in both directly-modulated and externally-modulated multi-band radio-over-fiber (RoF) systems. Similar characteristics of the multi-dimensional digital predistorter are identified in directly-modulated and externally-modulated RoF systems. The experimental results suggest implementing a memory-free multi-dimensional digital predistorter involving nonlinearity orders up to 5 at 2 × oversampling rate for practical multi-band RoF systems. Using the suggested parameters, the multi-dimensional DPD is able to improve the RF input power tolerance by greater than 3dB for each band in a two-band RoF system, indicating an enhancement of RF power transmitting efficiency. PMID:24663783

Chen, Hao; Li, Jianqiang; Xu, Kun; Pei, Yinqing; Dai, Yitang; Yin, Feifei; Lin, Jintong

2014-02-24

102

Scale-PC shielding analysis sequences  

SciTech Connect

The SCALE computational system is a modular code system for analyses of nuclear fuel facility and package designs. With the release of SCALE-PC Version 4.3, the radiation shielding analysis community now has the capability to execute the SCALE shielding analysis sequences contained in the control modules SAS1, SAS2, SAS3, and SAS4 on a MS- DOS personal computer (PC). In addition, SCALE-PC includes two new sequences, QADS and ORIGEN-ARP. The capabilities of each sequence are presented, along with example applications.

Bowman, S.M.

1996-05-01

103

Scaling Analysis of Affinity Propagation  

E-print Network

We analyze and exploit some scaling properties of the Affinity Propagation (AP) clustering algorithm proposed by Frey and Dueck (2007). First we observe that a divide and conquer strategy, used on a large data set hierarchically reduces the complexity ${\\cal O}(N^2)$ to ${\\cal O}(N^{(h+2)/(h+1)})$, for a data-set of size $N$ and a depth $h$ of the hierarchical strategy. For a data-set embedded in a $d$-dimensional space, we show that this is obtained without notably damaging the precision except in dimension $d=2$. In fact, for $d$ larger than 2 the relative loss in precision scales like $N^{(2-d)/(h+1)d}$. Finally, under some conditions we observe that there is a value $s^*$ of the penalty coefficient, a free parameter used to fix the number of clusters, which separates a fragmentation phase (for $ss^*$) of the underlying hidden cluster structure. At this precise point holds a self-similarity property which can be exploited by the hierarchical strategy to actually locate its position. From this observation, ...

Furtlehner, Cyril; Zhang, Xiangliang

2009-01-01

104

Scaling Analysis of Affinity Propagation Cyril Furtlehner,  

E-print Network

Scaling Analysis of Affinity Propagation Cyril Furtlehner, Mich`ele Sebag, and Xiangliang Zhang (Dated: June 9, 2010) We analyze and exploit some scaling properties of the Affinity Propagation (AP counterpart is known to be the belief-propagation (BP) algorithm of Pearl [4, 5]. This algorithm was initially

Paris-Sud XI, Université de

105

Low back pain in adolescent female rowers: a multi-dimensional intervention study.  

PubMed

The aim of this study was to determine whether a multi-dimensional intervention programme was effective in reducing the incidence of low back pain (LBP) and the associated levels of pain and disability in schoolgirl rowers. This non-randomised controlled trial involved an intervention (INT) group consisting of 90 schoolgirl rowers from one school and a control (CTRL) group consisting of 131 participants from three other schools. All participants in the INT group underwent a multi-dimensional programme that consisted of an individualised exercise programme based on an individual musculoskeletal screening (Week 1) and a LBP education session conducted by a physiotherapist (Week 2) and performed an off-water-conditioning programme conducted by a Physical Education teacher. All exercises were undertaken during the season. Primary outcome variables collected at Start-season, Mid-season, End-season and Post-season included the incidence of LBP and related levels of pain and disability. Secondary outcome variables from the bio-psycho-social domain were measured at Start-season and End-season in the INT group only. The INT group had a lower incidence of LBP at Mid-season and End-season and displayed significantly better results than the CTRL group for improvers and non-improvers with respect to the levels of pain and disability. The INT group following the intervention also displayed improved physical fitness levels, sat with significantly less anterior tilt of the pelvis and lumbar kyphosis when in their usual sitting posture and demonstrated positive changes in their behaviour. The multi-dimensional approach to reducing the incidence of LBP, pain and disability in schoolgirl rowers in this study was effective. Several secondary outcome variables measured in the INT group considered to be of importance in LBP significantly improved. These included physical fitness (aerobic conditioning, lower limb and back muscle endurance and sit and reach flexibility) and seated posture (usual and slump sitting). PMID:20549188

Perich, Debra; Burnett, Angus; O'Sullivan, Peter; Perkin, Chris

2011-01-01

106

2-D/Axisymmetric Formulation of Multi-dimensional Upwind Scheme  

NASA Technical Reports Server (NTRS)

A multi-dimensional upwind discretization of the two-dimensional/axisymmetric Navier-Stokes equations is detailed for unstructured meshes. The algorithm is an extension of the fluctuation splitting scheme of Sidilkover. Boundary conditions are implemented weakly so that all nodes are updated using the base scheme, and eigen-value limiting is incorporated to suppress expansion shocks. Test cases for Mach numbers ranging from 0.1-17 are considered, with results compared against an unstructured upwind finite volume scheme. The fluctuation splitting inviscid distribution requires fewer operations than the finite volume routine, and is seen to produce less artificial dissipation, leading to generally improved solution accuracy.

Wood, William A.; Kleb, William L.

2001-01-01

107

Applied multi-dimensional fusion for urban intelligence, surveillance, target acquisition, and reconnaissance  

NASA Astrophysics Data System (ADS)

The paper intends to show that Applied Multidimensional Fusion will bring the benefits that data fusion and related techniques will bring to Urban Intelligence Surveillance Target Acquisition and Reconnaissance (ISTAR) systems. In the course of this work it has been shown through the practical application of some of the multi-dimensional fusion research in the United Kingdom. This paper highlights work done in the area of: super-resolution, joint fusion, multi-resolution target detection and identification, and task based image and video fusion assessment. Work done to date has produced practical pertinent research products with direct applicability to the problems posed.

Mahmood, Asher; Tudor, Philip M.

2008-10-01

108

Algorithm for loading shot noise microbunching in multi-dimensional, free-electron laser simulation codes  

SciTech Connect

We discuss the underlying reasoning behind and the details of the numerical algorithm used in the GINGER free-electron laser(FEL) simulation code to load the initial shot noise microbunching on the electron beam. In particular, we point out that there are some additional subtleties which must be followed for multi-dimensional codes which are not necessary for one-dimensional formulations. Moreover, requiring that the higher harmonics of the microbunching also be properly initialized with the correct statistics leads to additional complexities. We present some numerical results including the predicted incoherent, spontaneous emission as tests of the shot noise algorithm's correctness.

Fawley, William M.

2002-03-25

109

Multi-Dimensional Asymptotically Stable 4th Order Accurate Schemes for the Diffusion Equation  

NASA Technical Reports Server (NTRS)

An algorithm is presented which solves the multi-dimensional diffusion equation on co mplex shapes to 4th-order accuracy and is asymptotically stable in time. This bounded-error result is achieved by constructing, on a rectangular grid, a differentiation matrix whose symmetric part is negative definite. The differentiation matrix accounts for the Dirichlet boundary condition by imposing penalty like terms. Numerical examples in 2-D show that the method is effective even where standard schemes, stable by traditional definitions fail.

Abarbanel, Saul; Ditkowski, Adi

1996-01-01

110

Development of a MultiDimensional Scale for Measuring Food Tourist Motivations  

Microsoft Academic Search

Food in tourism is becoming an important subject to researchers in the field of tourism and food service. Food and its related tourist activities have been ascribed into a new category of tourism called food tourism in which the motivation for traveling is to obtain special experiences from food. However, limited attention has been paid to explore precisely what factors

Young H. Kim; Ben K. Goh; Jingxue Yuan

2010-01-01

111

Query Driven Visualization of Large Scale Multi-Dimensional Astronomical Catalogs  

NASA Astrophysics Data System (ADS)

Met huidige telescopen worden miljarden bronnen waargenomen, waarvan honderden eigenschappen worden gemeten. Er zijn nieuwe technieken nodig om deze grote datasets interactief te kunnen visualiseren. In dit proefschrift wordt een vraaggestuurde manier van visualisatie geïntroduceerd, waarmee schaalbaarheid en flexibiliteit bereikt worden. Een belangrijk aspect hierin is dat wordt opgeslagen hoe sterrenkundige data wordt verwerkt. Hierdoor is het van elke dataset duidelijk hoe deze is gemaakt en is het mogelijk om data automatisch te genereren. Het resultaat hiervan is dat het vinden van bestaande data en het creëren van nieuwe data op dezelfde manier gebeurt, namelijk door het op te vragen. Een verzoek voor data kan op een implementatieonafhankelijke manier worden verwoord. Hierdoor kan het opvragen van data vanuit de visualisatie zelf gedaan kan worden, zonder dat de visualisatiesoftware kennis hoeft te hebben van de dataverwerking. Nieuwe data wordt alleen gemaakt als de bestaande data niet geschikt is om aan zo'n dataverzoek te voldoen. In dat geval wordt deze data zo gedefinieerd dat het zo herbruikbaar mogelijk is voor latere dataverzoeken. Vervolgens wordt alleen dat deel van de data gecreëerd dat daadwerkelijk nodig is voor de visualisatie. De data wordt alleen opgeslagen als de creatie ervan erg tijdrovend is. Aangezien nieuwe data automatisch op een zowel schaalbare als herbruikbare manier gemaakt wordt, hoeven zowel d

Buddelmeijer, Hugo

2011-07-01

112

Scaling the ISLE Framework: Validating Tests of Machine Translation Quality for MultiDimensional Measurement  

Microsoft Academic Search

Work on comparing a set of linguistic test scores for MT outpu t to a set of the same tests' scores for naturally-occurring target language text (Jones and Rusk 2000) broke new ground in automating MT Evaluation. However, the tests used were selected on an ad hoc basis. In this paper, we report on work to extend our understanding, through

Michelle Vanni; Keith J. Miller

113

A multi-dimensional scale for repositioning public park and recreation services  

E-print Network

consumers perceive competing products (Fill, 1999). Successful positioning results from an understanding of the attributes that are important to customers of a given product class. The firm should differentiate its product or service based... on these important attributes, and then specifically communicate its distinctive, important qualities to customers. Kotler?s (2000) commonly cited definition emphasizes manipulating the attributes of the product or service to create a niche in consumers? minds...

Kaczynski, Andrew Thomas

2004-09-30

114

POLARIZED LINE FORMATION IN MULTI-DIMENSIONAL MEDIA. V. EFFECTS OF ANGLE-DEPENDENT PARTIAL FREQUENCY REDISTRIBUTION  

SciTech Connect

The solution of polarized radiative transfer equation with angle-dependent (AD) partial frequency redistribution (PRD) is a challenging problem. Modeling the observed, linearly polarized strong resonance lines in the solar spectrum often requires the solution of the AD line transfer problems in one-dimensional or multi-dimensional (multi-D) geometries. The purpose of this paper is to develop an understanding of the relative importance of the AD PRD effects and the multi-D transfer effects and particularly their combined influence on the line polarization. This would help in a quantitative analysis of the second solar spectrum (the linearly polarized spectrum of the Sun). We consider both non-magnetic and magnetic media. In this paper we reduce the Stokes vector transfer equation to a simpler form using a Fourier decomposition technique for multi-D media. A fast numerical method is also devised to solve the concerned multi-D transfer problem. The numerical results are presented for a two-dimensional medium with a moderate optical thickness (effectively thin) and are computed for a collisionless frequency redistribution. We show that the AD PRD effects are significant and cannot be ignored in a quantitative fine analysis of the line polarization. These effects are accentuated by the finite dimensionality of the medium (multi-D transfer). The presence of magnetic fields (Hanle effect) modifies the impact of these two effects to a considerable extent.

Anusha, L. S.; Nagendra, K. N. [Indian Institute of Astrophysics, Koramangala, 2nd Block, Bangalore 560 034 (India)

2012-02-10

115

An interface capturing method with a continuous function: The THINC method with multi-dimensional reconstruction  

NASA Astrophysics Data System (ADS)

An interface capturing method with a continuous function is proposed within the framework of the volume-of-fluid (VOF) method. Being different from the traditional VOF methods that require a geometrical reconstruction and identify the interface by a discontinuous Heaviside function, the present method makes use of the hyperbolic tangent function (known as one of the sigmoid type functions) in the tangent of hyperbola interface capturing (THINC) method [F. Xiao, Y. Honma, K. Kono, A simple algebraic interface capturing scheme using hyperbolic tangent function, Int. J. Numer. Methods Fluids 48 (2005) 1023-1040] to retrieve the interface in an algebraic way from the volume-fraction data of multi-component materials. Instead of the 1D reconstruction in the original THINC method, a multi-dimensional hyperbolic tangent function is employed in the present new approach. The present scheme resolves moving interface with geometric faithfulness and compact thickness, and has at least the following advantages: (1) the geometric reconstruction is not required in constructing piecewise approximate functions; (2) besides a piecewise linear interface, curved (quadratic) surface can be easily constructed as well; and (3) the continuous multi-dimensional hyperbolic tangent function allows the direct calculations of derivatives and normal vectors. Numerical benchmark tests including transport of moving interface and incompressible interfacial flows are presented to validate the numerical accuracy for interface capturing and to show the capability for practical problems such as a stationary circular droplet, a drop oscillation, a shear-induced drop deformation and a rising bubble.

Ii, Satoshi; Sugiyama, Kazuyasu; Takeuchi, Shintaro; Takagi, Shu; Matsumoto, Yoichiro; Xiao, Feng

2012-03-01

116

Differentially Private Synthesization of Multi-Dimensional Data using Copula Functions  

PubMed Central

Differential privacy has recently emerged in private statistical data release as one of the strongest privacy guarantees. Most of the existing techniques that generate differentially private histograms or synthetic data only work well for single dimensional or low-dimensional histograms. They become problematic for high dimensional and large domain data due to increased perturbation error and computation complexity. In this paper, we propose DPCopula, a differentially private data synthesization technique using Copula functions for multi-dimensional data. The core of our method is to compute a differentially private copula function from which we can sample synthetic data. Copula functions are used to describe the dependence between multivariate random vectors and allow us to build the multivariate joint distribution using one-dimensional marginal distributions. We present two methods for estimating the parameters of the copula functions with differential privacy: maximum likelihood estimation and Kendall’s ? estimation. We present formal proofs for the privacy guarantee as well as the convergence property of our methods. Extensive experiments using both real datasets and synthetic datasets demonstrate that DPCopula generates highly accurate synthetic multi-dimensional data with significantly better utility than state-of-the-art techniques.

Li, Haoran; Xiong, Li; Jiang, Xiaoqian

2014-01-01

117

Ion-acoustic solitary waves and their multi-dimensional instability in a magnetized degenerate plasma  

SciTech Connect

A rigorous theoretical investigation has been made on Zakharov-Kuznetsov (ZK) equation of ion-acoustic (IA) solitary waves (SWs) and their multi-dimensional instability in a magnetized degenerate plasma which consists of inertialess electrons, inertial ions, negatively, and positively charged stationary heavy ions. The ZK equation is derived by the reductive perturbation method, and multi-dimensional instability of these solitary structures is also studied by the small-k (long wave-length plane wave) perturbation expansion technique. The effects of the external magnetic field are found to significantly modify the basic properties of small but finite-amplitude IA SWs. The external magnetic field and the propagation directions of both the nonlinear waves and their perturbation modes are found to play a very important role in changing the instability criterion and the growth rate of the unstable IA SWs. The basic features (viz., amplitude, width, instability, etc.) and the underlying physics of the IA SWs, which are relevant to space and laboratory plasma situations, are briefly discussed.

Haider, M. M. [Department of Physics, Mawlana Bhashani Science and Technology University, Santosh, Tangail 1902 (Bangladesh); Mamun, A. A. [Department of Physics, Jahangirnagar University, Savar, Dhaka 1342 (Bangladesh)

2012-10-15

118

Natural attenuation of chlorinated ethene compounds: model development and field-scale application at the Dover site  

Microsoft Academic Search

A multi-dimensional and multi-species reactive transport model was developed to aid in the analysis of natural attenuation design at chlorinated solvent sites. The model can simulate several simultaneously occurring attenuation processes including aerobic and anaerobic biological degradation processes. The developed model was applied to analyze field-scale transport and biodegradation processes occurring at the Area-6 site in Dover Air Force Base,

T. Prabhakar Clement; Christian D. Johnson; Yunwei Sun; Gary M. Klecka; Craig Bartlett

2000-01-01

119

Multi-dimensional instability of dust-acoustic solitary waves in a magnetized plasma with opposite polarity dust  

SciTech Connect

Dust-acoustic (DA) solitary structures and their multi-dimensional instability in a magnetized dusty plasma (containing inertial negatively and positively charged dust particles, and Boltzmann electrons and ions) have been theoretically investigated by the reductive perturbation method, and the small-k perturbation expansion technique. It has been found that the basic features (polarity, speed, height, thickness, etc.) of such DA solitary structures, and their multi-dimensional instability criterion or growth rate are significantly modified by the presence of opposite polarity dust particles and external magnetic field. The implications of our results in space and laboratory dusty plasma systems have been briefly discussed.

Akhter, T.; Hossain, M. M.; Mamun, A. A. [Department of Physics, Jahangirnagar University, Savar, Dhaka-1342 (Bangladesh)

2012-09-15

120

Sequential acquisition of multi-dimensional heteronuclear chemical shift correlation spectra with 1H detection  

PubMed Central

RF pulse schemes for the simultaneous acquisition of heteronuclear multi-dimensional chemical shift correlation spectra, such as {HA(CA)NH & HA(CACO)NH}, {HA(CA)NH & H(N)CAHA} and {H(N)CAHA & H(CC)NH}, that are commonly employed in the study of moderately-sized protein molecules, have been implemented using dual sequential 1H acquisitions in the direct dimension. Such an approach is not only beneficial in terms of the reduction of experimental time as compared to data collection via two separate experiments but also facilitates the unambiguous sequential linking of the backbone amino acid residues. The potential of sequential 1H data acquisition procedure in the study of RNA is also demonstrated here. PMID:24671105

Bellstedt, Peter; Ihle, Yvonne; Wiedemann, Christoph; Kirschstein, Anika; Herbst, Christian; Gorlach, Matthias; Ramachandran, Ramadurai

2014-01-01

121

Racial-ethnic self-schemas: Multi-dimensional identity-based motivation  

PubMed Central

Prior self-schema research focuses on benefits of being schematic vs. aschematic in stereotyped domains. The current studies build on this work, examining racial-ethnic self-schemas as multi-dimensional, containing multiple, conflicting, and non-integrated images. A multidimensional perspective captures complexity; examining net effects of dimensions predicts within-group differences in academic engagement and well-being. When racial-ethnicity self-schemas focus attention on membership in both in-group and broader society, engagement with school should increase since school is not seen as out-group defining. When racial-ethnicity self-schemas focus attention on inclusion (not obstacles to inclusion) in broader society, risk of depressive symptoms should decrease. Support for these hypotheses was found in two separate samples (8th graders, n = 213, 9th graders followed to 12th grade n = 141). PMID:19122837

Oyserman, Daphna

2008-01-01

122

Minimizing I/O Costs of Multi-Dimensional Queries with Bitmap Indices  

E-print Network

Bitmap indices have been widely used in scientific applications and commercial systems for processing complex, multi-dimensional queries where traditional tree-based indices would not work efficiently. A common approach for reducing the size of a bitmap index for high cardinality attributes is to group ranges of values of an attribute into bins and then build a bitmap for each bin rather than a bitmap for each value of the attribute. Binning reduces storage costs, however, results of queries based on bins often require additional filtering for discarding false positives, i.e., records in the result that do not satisfy the query constraints. This additional filtering, also known as candidate checking, requires access to the base data on disk and involves significant I/O costs. This paper

Doron Rotem; Kurt Stockinger; Kesheng Wu

2006-01-01

123

Deadlock-free class routes for collective communications embedded in a multi-dimensional torus network  

DOEpatents

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.

Chen, Dong; Eisley, Noel A.; Steinmacher-Burow, Burkhard; Heidelberger, Philip

2013-01-29

124

Extending the Implicit Association Test (IAT): Assessing Consumer Attitudes Based on Multi-Dimensional Implicit Associations  

PubMed Central

Background The authors present a procedural extension of the popular Implicit Association Test (IAT; [1]) that allows for indirect measurement of attitudes on multiple dimensions (e.g., safe–unsafe; young–old; innovative–conventional, etc.) rather than on a single evaluative dimension only (e.g., good–bad). Methodology/Principal Findings In two within-subjects studies, attitudes toward three automobile brands were measured on six attribute dimensions. Emphasis was placed on evaluating the methodological appropriateness of the new procedure, providing strong evidence for its reliability, validity, and sensitivity. Conclusions/Significance This new procedure yields detailed information on the multifaceted nature of brand associations that can add up to a more abstract overall attitude. Just as the IAT, its multi-dimensional extension/application (dubbed md-IAT) is suited for reliably measuring attitudes consumers may not be consciously aware of, able to express, or willing to share with the researcher [2], [3]. PMID:21246037

Gattol, Valentin; Saaksjarvi, Maria; Carbon, Claus-Christian

2011-01-01

125

High-Level Waste Tanks Multi-Dimensional Contaminant Transport Model Development  

SciTech Connect

A suite of multi-dimensional computer models was developed to analyze the transport of residual contamination from high-level waste tanks through the subsurface to seeplines. Cases analyzed ranged from all the tanks in the F- and H-tank farms for an overall look; to the Tank 17-20 4-pack to study plume interaction; to individual tanks, such as Tank 17 and 20 for comparison with one-dimensional and modeling. The main purpose of this work was to develop and test the models, so only two relatively conservative contaminants were examined, Tc-99 and I-129. More complex analyses, such as solubility-limited species and radionuclides that head a decay chain were not addressed in this study.

Collard, L.B.

1999-11-15

126

Ionizing shocks in argon. Part II: Transient and multi-dimensional effects  

SciTech Connect

We extend the computations of ionizing shocks in argon to the unsteady and multi-dimensional, using a collisional-radiative model and a single-fluid, two-temperature formulation of the conservation equations. It is shown that the fluctuations of the shock structure observed in shock-tube experiments can be reproduced by the numerical simulations and explained on the basis of the coupling of the nonlinear kinetics of the collisional-radiative model with wave propagation within the induction zone. The mechanism is analogous to instabilities of detonation waves and also produces a cellular structure commonly observed in gaseous detonations. We suggest that detailed simulations of such unsteady phenomena can yield further information for the validation of nonequilibrium kinetics.

Kapper, M. G.; Cambier, J.-L. [Air Force Research Laboratory, Edwards AFB, CA 93524 (United States)

2011-06-01

127

FEMVib, an ab initio multi-dimensional solver for probing vibrational dynamics in polyatomic molecules and free radicals  

NASA Astrophysics Data System (ADS)

Accurate prediction of the vibrational spectra in polyatomic molecules and free radicals depends on obtaining high quality solutions to the vibrational Schrodinger equation. The quantum simple harmonic oscillator provides the traditional first approximation for modeling molecular vibrational states. Rarely does a vibrational analysis extend beyond this first approximation, and harmonic energy levels are routinely used to predict the infrared spectra and other dynamical properties of molecules. However, there are many large-amplitude molecular motions that are extremely anharmonic, including internal torsions about atom-atom single bonds, bending and stretching of weak bonds in van der Waals complexes, and isomerization along relocalization coordinates in free radicals. In these cases, the harmonic treatment provided by electronic structure quantum chemistry packages is completely inadequate. Furthermore, the anharmonicity often includes strong coupling among two or more distinct vibrational coordinates, necessitating a multi-dimensional analysis of the vibrational Schrodinger equation along the coupled coordinates. A novel ab initio solver package, FEMVib, is developed within the finite element method (FEM) framework. A mixed programming paradigm that combines C++, Fortran and Python is employed to take advantage of existing numerical libraries. FEMVib has been rigorously tested to resolve the eigenvalues and wavefunctions of hundreds of vibrational energy states to high accuracy and precision. It may be used to calculate the complete vibrational spectra of triatomic molecules or to approximate larger systems through a "relaxed" model that allows complete coupling of up to three selected vibrational coordinates. FEMVib provides physical chemists with a general, robust and accurate computational tool for molecular vibrational analysis.

Xu, Dong

128

A scaling analysis of ozone photochemistry  

NASA Astrophysics Data System (ADS)

A scaling analysis has been used to capture the integrated behaviour of several photochemical mechanisms for a wide range of precursor concentrations and a variety of environmental conditions. The Buckingham Pi method of dimensional analysis was used to express the relevant variables in terms of dimensionless groups. These grouping show maximum ozone, initial NOx and initial VOC concentrations are made non-dimensional by the average NO2 photolysis rate (jav) and the rate constant for the NO-O3 titration reaction (kNO); temperature by the NO-O3 activation energy (ENO) and Boltzmann constant (k) and total irradiation time by the cumulative jav?t photolysis rate. The analysis shows dimensionless maximum ozone concentration can be described by a product of powers of dimensionless initial NOx concentration, dimensionless temperature, and a similarity curve directly dependent on the ratio of initial VOC to NOx concentration and implicitly dependent on the cumulative NO2 photolysis rate. When Weibull transformed, the similarity relationship shows a scaling break with dimensionless model output clustering onto two straight line segments, parameterized using four variables: two describing the slopes of the line segments and two giving the location of their intersection. A fifth parameter is used to normalize the model output. The scaling analysis, similarity curve and parameterization appear to be independent of the details of the chemical mechanism, hold for a variety of VOC species and mixtures and a wide range of temperatures and actinic fluxes.

Ainslie, B.; Steyn, D. G.

2006-09-01

129

Determination of ethyl carbamate in alcoholic beverages by capillary multi-dimensional gas chromatography with thermionic specific detection  

Microsoft Academic Search

A specific, sensitive capillary multi-dimensional gas chromatographic method with thermionic specific detection (TSD) combined with internal standard methodology to identify ethyl carbamate (EC), a well known carcinogen, in various fermented alcoholic beverages is described. The basic procedures for sample preparation were similar to a modification of the LCBO (Liquor Control Board of Ontario) procedure, except that isopropyl carbamate (i-PC) was

Ya-Ping Ma; Fu-Quan Deng; Dai-Zhou Chen; Shou-Wei Sun

1995-01-01

130

Application of the MultiDimensional Positive Definite Advection Transport Algorithm (MPDATA) to Environmental Modeling on Adaptive Unstructured Grids  

Microsoft Academic Search

Twenty years ago, the multi-dimensional, positive definite, advection transport algorithm was introduced by Smolarkiewicz. Over the two decades since, it has been applied countless times to numerous problems, however almost always on rectilinear grids. One of the few exceptions is the Operational Multiscale Environment model with Grid Adaptivity (OMEGA), an atmospheric simulation system originally designed to simulate atmospheric dispersion in

N. AHMAD; DAVID P. BACON; MARY S. HALL; ANANTHAKRISHNA SARMA

131

A Reactive Local Search-Based Algorithm for the Multiple-Choice MultiDimensional Knapsack Problem  

Microsoft Academic Search

In this paper, we approximately solve the multiple-choice multi-dimensional knapsack prob- lem. We propose an algorithm which is based upon reactive local search and where an explicit check for the repetition of configurations is added to the local search. The algorithm starts by an initial solution and improved by using a fast iterative procedure. Later, both deblocking and degrading procedures

M. HIFI; M. MICHRAFY; A. SBIHI

2005-01-01

132

Reduced Dynamic Time Warping for Handwriting Recognition Based on Multi dimensional Time Series of a Novel Pen Device  

Microsoft Academic Search

The purpose of this paper is to present a Dynamic Time Warping technique which reduces significantly the data processing time and memory size of multi-dimensional time series sampled by the biometric smart pen device BiSP. The acquisition device is a novel ballpoint pen equipped with a diversity of sensors for monitoring the kinematics and dynamics of handwriting movement. The DTW

Muzaffar Bashir; Jürgen Kempf

2008-01-01

133

Accelerated Multi-Dimensional RF Pulse Design for Parallel Transmission Using Concurrent Computation on Multiple Graphics Processing Units  

PubMed Central

Multi-dimensional RF pulses are of current interest due to their promise for improving high field imaging as well as for optimizing parallel transmission methods. One major drawback is that the computation time of numerically designed multi-dimensional RF pulses increases rapidly with their resolution and number of transmitters. This is critical because the construction of multi-dimensional RF pulses often needs to be in real time. The use of graphics processing units for computations is a recent approach for accelerating image reconstruction applications. We propose the use of graphics processing units for the design of multi-dimensional RF pulses including the utilization of parallel transmitters. Using a desktop computer with four NVIDIA Tesla C1060 computing processors, we found acceleration factors on the order of twenty for standard eight-transmitter 2D spiral RF pulses with a 64 × 64 excitation resolution and a ten-microsecond dwell time. We also show that even greater acceleration factors can be achieved for more complex RF pulses. PMID:21264929

Deng, Weiran; Yang, Cungeng; Stenger, V. Andrew

2010-01-01

134

The multi-dimensional additionality of innovation policies. A multi-level application to Italy and Spain.  

E-print Network

1 The multi-dimensional additionality of innovation policies. A multi-level application to Italy, at the national and regional level (multi-level). An empirical application is carried out for Italy and Spain of different variables in Spain (product innovations) and in Italy (process innovations). Overall, only

Sussex, University of

135

A high order cell-centered semi-Lagrangian scheme for multi-dimensional kinetic simulations of neutral gas flows  

NASA Astrophysics Data System (ADS)

The term 'Convected Scheme' (CS) refers to a family of algorithms, most usually applied to the solution of Boltzmann's equation, which uses a method of characteristics in an integral form to project an initial cell forward to a group of final cells. As such the CS is a 'forward-trajectory' semi-Lagrangian scheme. For multi-dimensional simulations of neutral gas flows, the cell-centered version of this semi-Lagrangian (CCSL) scheme has advantages over other options due to its implementation simplicity, low memory requirements, and easier treatment of boundary conditions. The main drawback of the CCSL-CS to date has been its high numerical diffusion in physical space, because of the 2nd order remapping that takes place at the end of each time step. By means of a modified equation analysis, it is shown that a high order estimate of the remapping error can be obtained a priori, and a small correction to the final position of the cells can be applied upon remapping, in order to achieve full compensation of this error. The resulting scheme is 4th order accurate in space while retaining the desirable properties of the CS: it is conservative and positivity-preserving, and the overall algorithm complexity is not appreciably increased. Two monotone (i.e. non-oscillating) versions of the fourth order CCSL-CS are also presented: one uses a common flux-limiter approach; the other uses a non-polynomial reconstruction to evaluate the derivatives of the density function. The method is illustrated in simple one- and two-dimensional examples, and a fully 3D solution of the Boltzmann equation describing expansion of a gas into vacuum through a cylindrical tube.

Güçlü, Y.; Hitchon, W. N. G.

2012-04-01

136

Large-Scale Visual Data Analysis  

NASA Astrophysics Data System (ADS)

Modern high performance computers have speeds measured in petaflops and handle data set sizes measured in terabytes and petabytes. Although these machines offer enormous potential for solving very large-scale realistic computational problems, their effectiveness will hinge upon the ability of human experts to interact with their simulation results and extract useful information. One of the greatest scientific challenges of the 21st century is to effectively understand and make use of the vast amount of information being produced. Visual data analysis will be among our most most important tools in helping to understand such large-scale information. Our research at the Scientific Computing and Imaging (SCI) Institute at the University of Utah has focused on innovative, scalable techniques for large-scale 3D visual data analysis. In this talk, I will present state- of-the-art visualization techniques, including scalable visualization algorithms and software, cluster-based visualization methods and innovate visualization techniques applied to problems in computational science, engineering, and medicine. I will conclude with an outline for a future high performance visualization research challenges and opportunities.

Johnson, Chris

2014-04-01

137

MUlti-Dimensional Spline-Based Estimator (MUSE) for Motion Estimation: Algorithm Development and Initial Results  

PubMed Central

Image registration and motion estimation play central roles in many fields, including RADAR, SONAR, light microscopy, and medical imaging. Because of its central significance, estimator accuracy, precision, and computational cost are of critical importance. We have previously presented a highly accurate, spline-based time delay estimator that directly determines sub-sample time delay estimates from sampled data. The algorithm uses cubic splines to produce a continuous representation of a reference signal and then computes an analytical matching function between this reference and a delayed signal. The location of the minima of this function yields estimates of the time delay. In this paper we describe the MUlti-dimensional Spline-based Estimator (MUSE) that allows accurate and precise estimation of multidimensional displacements/strain components from multidimensional data sets. We describe the mathematical formulation for two- and three-dimensional motion/strain estimation and present simulation results to assess the intrinsic bias and standard deviation of this algorithm and compare it to currently available multi-dimensional estimators. In 1000 noise-free simulations of ultrasound data we found that 2D MUSE exhibits maximum bias of 2.6 × 10?4 samples in range and 2.2 × 10?3 samples in azimuth (corresponding to 4.8 and 297 nm, respectively). The maximum simulated standard deviation of estimates in both dimensions was comparable at roughly 2.8 × 10?3 samples (corresponding to 54 nm axially and 378 nm laterally). These results are between two and three orders of magnitude better than currently used 2D tracking methods. Simulation of performance in 3D yielded similar results to those observed in 2D. We also present experimental results obtained using 2D MUSE on data acquired by an Ultrasonix Sonix RP imaging system with an L14-5/38 linear array transducer operating at 6.6 MHz. While our validation of the algorithm was performed using ultrasound data, MUSE is broadly applicable across imaging applications. PMID:18807190

Viola, Francesco; Coe, Ryan L.; Owen, Kevin; Guenther, Drake A.; Walker, William F.

2008-01-01

138

Effects of bathymetric lidar errors on flow properties predicted with a multi-dimensional hydraulic model  

NASA Astrophysics Data System (ADS)

remote sensing technologies and improved computer performance now allow numerical flow modeling over large stream domains. However, there has been limited testing of whether channel topography can be remotely mapped with accuracy necessary for such modeling. We assessed the ability of the Experimental Advanced Airborne Research Lidar, to support a multi-dimensional fluid dynamics model of a small mountain stream. Random point elevation errors were introduced into the lidar point cloud, and predictions of water surface elevation, velocity, bed shear stress, and bed mobility were compared to those made without the point errors. We also compared flow model predictions using the lidar bathymetry with those made using a total station channel field survey. Lidar errors caused < 1 cm changes in the modeled water surface elevations. Effects of the point errors on other flow characteristics varied with both the magnitude of error and the local spatial density of lidar data. Shear stress errors were greatest where flow was naturally shallow and fast, and lidar errors caused the greatest changes in flow cross-sectional area. The majority of the stress errors were less than ± 5 Pa. At near bankfull flow, the predicted mobility state of the median grain size changed over ? 1.3% of the model domain as a result of lidar elevation errors and ? 3% changed mobility in the comparison of lidar and ground-surveyed topography. In this riverscape, results suggest that an airborne bathymetric lidar can map channel topography with sufficient accuracy to support a numerical flow model.

McKean, J.; Tonina, D.; Bohn, C.; Wright, C. W.

2014-03-01

139

Opportunities in multi dimensional trace metal imaging: Taking copper associated disease research to the next level  

PubMed Central

Copper plays an important role in numerous biological processes across all living systems predominantly because of its versatile redox behavior. Cellular copper homeostasis is tightly regulated and disturbances lead to severe disorders such as Wilson disease (WD) and Menkes disease. Age related changes of copper metabolism have been implicated in other neurodegenerative disorders such as Alzheimer’s disease (AD). The role of copper in these diseases has been topic of mostly bioinorganic research efforts for more than a decade, metal-protein interactions have been characterized and cellular copper pathways have been described. Despite these efforts, crucial aspects of how copper is associated with AD, for example, is still only poorly understood. To take metal related disease research to the next level, emerging multi dimensional imaging techniques are now revealing the copper metallome as the basis to better understand disease mechanisms. This review will describe how recent advances in X-ray fluorescence microscopy and fluorescent copper probes have started to contribute to this field specifically WD and AD. It furthermore provides an overview of current developments and future applications in X-ray microscopic methodologies. PMID:23079951

Vogt, Stefan; Ralle, Martina

2012-01-01

140

Operationalising the Sustainable Knowledge Society Concept through a Multi-dimensional Scorecard  

NASA Astrophysics Data System (ADS)

Since the early 21st Century, building a Knowledge Society represents an aspiration not only for the developed countries, but for the developing ones too. There is an increasing concern worldwide for rendering this process manageable towards a sustainable, equitable and ethically sound societal system. As proper management, including at the societal level, requires both wisdom and measurement, the operationalisation of the Knowledge Society concept encompasses a qualitative side, related to vision-building, and a quantitative one, pertaining to designing and using dedicated metrics. The endeavour of enabling policy-makers mapping, steering and monitoring the sustainable development of the Knowledge Society at national level, in a world increasingly based on creativity, learning and open communication, led researchers to devising a wide range of composite indexes. However, as such indexes are generated through weighting and aggregation, their usefulness is limited to retrospectively assessing and comparing levels and states already attained; therefore, to better serve policy-making purposes, composite indexes should be complemented by other instruments. Complexification, inspired by the systemic paradigm, allows obtaining "rich pictures" of the Knowledge Society; to this end, a multi-dimensional scorecard of the Knowledge Society development is hereby suggested, that seeks a more contextual orientation towards sustainability. It is assumed that, in the case of the Knowledge Society, the sustainability condition goes well beyond the "greening" desideratum and should be of a higher order, relying upon the conversion of natural and productive life-cycles into virtuous circles of self-sustainability.

Dragomirescu, Horatiu; Sharma, Ravi S.

141

Numerical Magnetohydrodynamics in Astrophysics: Algorithm and Tests for Multi-Dimensional Flow  

E-print Network

We present for astrophysical use a multi-dimensional numerical code to solve the equations for ideal magnetohydrodynamics (MHD). It is based on an explicit finite difference method on an Eulerian grid, called the Total Variation Diminishing (TVD) scheme, which is a second-order-accurate extension of the Roe-type upwind scheme. Multiple spatial dimensions are treated through a Strang-type operator splitting. The constraint of a divergence-free field is enforced exactly by calculating a correction via a gauge transformation in each time step. Results from two-dimensional shock tube tests show that the code captures correctly discontinuities in all three MHD waves families as well as contact discontinuities. The numerical viscosities and resistivity in the code, which are useful in order to understand simulations involving turbulent flows, are estimated through the decay of two-dimensional linear waves. Finally, the robustness of the code in two-dimensions is demonstrated through calculations of the Kelvin-Helmholtz instability and the Orszag-Tang vortex.

Dongsu Ryu; T. W. Jones; Adam Frank

1995-05-17

142

New methodology for multi-dimensional spinal joint testing with a parallel robot.  

PubMed

Six degree-of-freedom (6DOF) robots can be used to examine joints and their mechanical properties with the spatial freedom encountered physiologically. Parallel robots are capable of 6DOF motion under large payloads making them ideal for joint testing. This study developed and assessed novel methods for spinal joint testing with a custom-built parallel robot implementing hybrid load-position control. We hypothesized these methods would allow multi-dimensional control of joint loading scenarios, resulting in physiological joint motions. Tests were performed in 3DOF and 6DOF. 3DOF methods controlled the forces and the principal moment within +/-10 N and 0.25 N m under combined bending and compressive loads. 6DOF tests required larger tolerances for convergence due to machine compliance, however expected motion patterns were still observed. The unique mechanism and control approaches show promise for enabling complex three-dimensional loading patterns for in vitro joint biomechanics, and could facilitate research using specimens with unknown, changing, or nonlinear load-deformation properties. PMID:17235615

Walker, Matthew R; Dickey, James P

2007-03-01

143

A SECOND-ORDER GODUNOV METHOD FOR MULTI-DIMENSIONAL RELATIVISTIC MAGNETOHYDRODYNAMICS  

SciTech Connect

We describe a new Godunov algorithm for relativistic magnetohydrodynamics (RMHD) that combines a simple, unsplit second-order accurate integrator with the constrained transport (CT) method for enforcing the solenoidal constraint on the magnetic field. A variety of approximate Riemann solvers are implemented to compute the fluxes of the conserved variables. The methods are tested with a comprehensive suite of multi-dimensional problems. These tests have helped us develop a hierarchy of correction steps that are applied when the integration algorithm predicts unphysical states due to errors in the fluxes, or errors in the inversion between conserved and primitive variables. Although used exceedingly rarely, these corrections dramatically improve the stability of the algorithm. We present preliminary results from the application of these algorithms to two problems in RMHD: the propagation of supersonic magnetized jets and the amplification of magnetic field by turbulence driven by the relativistic Kelvin-Helmholtz instability (KHI). Both of these applications reveal important differences between the results computed with Riemann solvers that adopt different approximations for the fluxes. For example, we show that the use of Riemann solvers that include both contact and rotational discontinuities can increase the strength of the magnetic field within the cocoon by a factor of 10 in simulations of RMHD jets and can increase the spectral resolution of three-dimensional RMHD turbulence driven by the KHI by a factor of two. This increase in accuracy far outweighs the associated increase in computational cost. Our RMHD scheme is publicly available as part of the Athena code.

Beckwith, Kris [JILA, University of Colorado at Boulder, 440 UCB Boulder, CO 80301 (United States); Stone, James M., E-mail: kris.beckwith@jila.colorado.edu, E-mail: jstone@astro.princeton.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

2011-03-15

144

Software Defined Networking (SDN) controlled all optical switching networks with multi-dimensional switching architecture  

NASA Astrophysics Data System (ADS)

Ultrahigh throughout capacity requirement is challenging the current optical switching nodes with the fast development of data center networks. Pbit/s level all optical switching networks need to be deployed soon, which will cause the high complexity of node architecture. How to control the future network and node equipment together will become a new problem. An enhanced Software Defined Networking (eSDN) control architecture is proposed in the paper, which consists of Provider NOX (P-NOX) and Node NOX (N-NOX). With the cooperation of P-NOX and N-NOX, the flexible control of the entire network can be achieved. All optical switching network testbed has been experimentally demonstrated with efficient control of enhanced Software Defined Networking (eSDN). Pbit/s level all optical switching nodes in the testbed are implemented based on multi-dimensional switching architecture, i.e. multi-level and multi-planar. Due to the space and cost limitation, each optical switching node is only equipped with four input line boxes and four output line boxes respectively. Experimental results are given to verify the performance of our proposed control and switching architecture.

Zhao, Yongli; Ji, Yuefeng; Zhang, Jie; Li, Hui; Xiong, Qianjin; Qiu, Shaofeng

2014-08-01

145

Time scale analysis of ISTTOK probe data  

SciTech Connect

Magnetic and turbulent activity in a tokamak plasma discharge may evolve in a complex trend during the discharge. In the ISTTOK tokamak, characterised by a short 30ms pulse duration, particle confinement of the order 0.3 ms and typical burst-like activity, the analysis of the time scales involved in the plasma activity is even more demanding. In this work, use is made of the Empirical Mode Decomposition (EMD) method as a tool for turbulence and MHD instability analysis obtained with Langmuir and magnetic probes, respectively. The time evolution of the energy content and wavenumber characterisation of fluctuating potential, edge plasma density and perturbed magnetic fields is investigated, with special emphasis on discharges where both limiter and electrode biasing were used to induce local sheared electric fields, thus affecting turbulence and consequently particle confinement.

Coelho, R.; Alves, D.; Silva, C. [Associacao Euratom/IST, Centro de Fusao Nuclear, 1049-001 Lisboa (Portugal)

2008-04-07

146

Scaling analysis of negative differential thermal resistance  

NASA Astrophysics Data System (ADS)

Negative differential thermal resistance (NDTR) can be generated for any one-dimensional heat flow with a temperature-dependent thermal conductivity. In a system-independent scaling analysis, the general condition for the occurrence of NDTR is found to be an inequality with three scaling exponents: n1n2<-(1+n3), where n1?(-?,+?) describes a particular way of varying the temperature difference, and n2 and n3 describe, respectively, the dependence of the thermal conductivity on an average temperature and on the temperature difference. For cases with a temperature-dependent thermal conductivity, i.e. n2?0, NDTR can always be generated with a suitable choice of n1 such that this inequality is satisfied. The results explain the illusory absence of a NDTR regime in certain lattices and predict new ways of generating NDTR, where such predictions have been verified numerically. The analysis will provide insights for a designing of thermal devices, and for a manipulation of heat flow in experimental systems, such as nanotubes.

Chan, Ho-Kei; He, Dahai; Hu, Bambi

2014-05-01

147

SCALABLE PARALLEL APPROXIMATE FORMULATIONS OF MULTI DIMENSIONAL SPATIAL AUTOREGRESSION MODELS FOR SPATIAL DATA MINING 1  

Microsoft Academic Search

The spatial auto-regression (SAR) model is a popula r spatial data analysis technique which has been used in many applications with geo-spatial datasets. Howeve r, exact solutions for estimating SAR parameters are computationally expensive due to the need to compute all the eigen-values of a very large matrix . Therefore, serial solutions for the SAR model do not scale up

Shashi Shekhar; Baris M. Kazar; David J. Lilja

148

Statistical approach and benchmarking for modeling of multi-dimensional behavior in TRISO-coated fuel particles  

Microsoft Academic Search

The fundamental design for a gas-cooled reactor relies on the behavior of the coated particle fuel. The coating layers, termed the TRISO coating, act as a mini-pressure vessel that retains fission products. Results of US irradiation experiments show that many more fuel particles have failed than can be attributed to one-dimensional pressure vessel failures alone. Post-irradiation examinations indicate that multi-dimensional

Gregory K Miller; David A Petti; Dominic J Varacalle; John T Maki

2003-01-01

149

A Reactive Local Search-Based Algorithm for the Multiple-Choice MultiDimensional Knapsack Problem  

Microsoft Academic Search

In this paper, we approximately solve the multiple-choice multi-dimensional knapsack problem. We propose an algorithm which\\u000a is based upon reactive local search and where an explicit check for the repetition of configurations is added to the local\\u000a search. The algorithm starts by an initial solution and improved by using a fast iterative procedure. Later, both deblocking and degrading procedures are

M. Hifi; M. Michrafy; A. Sbihi

2006-01-01

150

Multi-dimensional upwind fluctuation splitting scheme with mesh adaption for hypersonic viscous flow  

NASA Astrophysics Data System (ADS)

A multi-dimensional upwind fluctuation splitting scheme is developed and implemented for two dimensional and axisymmetric formulations of the Navier-Stokes equations on unstructured meshes. Key features of the scheme are the compact stencil, full upwinding, and non-linear discretization which allow for second-order accuracy with enforced positivity. Throughout, the fluctuation splitting scheme is compared to a current state-of-the-art finite volume approach, a second-order, dual mesh upwind flux difference splitting scheme (DMFDSFV), and is shown to produce more accurate results using fewer computer resources for a wide range of test cases. The scalar test cases include advected shear, circular advection, non-linear advection with coalescing shock and expansion fans, and advection-diffusion. For all scalar cases the fluctuation splitting scheme is more accurate, and the primary mechanism for the improved fluctuation splitting performance is shown to be the reduced production of artificial dissipation relative to DMFDSFV. The most significant scalar result is for combined advection-diffusion, where the present fluctuation splitting scheme is able to resolve the physical dissipation from the artificial dissipation on a much coarser mesh than DMFDSFV is able to, allowing order-of-magnitude reductions in solution time. Among the inviscid test cases the converging supersonic streams problem is notable in that the fluctuation splitting scheme exhibits superconvergent third-order spatial accuracy. For the inviscid cases of a supersonic diamond airfoil, supersonic slender cone, and incompressible circular bump the fluctuation splitting drag coefficient errors are typically half the DMFDSFV drag errors. However, for the incompressible inviscid sphere the fluctuation splitting drag error is larger than for DMFDSFV. A Blasius flat plate viscous validation case reveals a more accurate v-velocity profile for fluctuation splitting, and the reduced artificial dissipation production is shown relative to DMFDSFV. Remarkably the fluctuation splitting scheme shows grid converged skin friction coefficients with only five points in the boundary layer for this case. A viscous Mach 17.6 (perfect gas) cylinder case demonstrates solution monotonicity and heat transfer capability with the fluctuation splitting scheme. While fluctuation splitting is recommended over DMFDSFV, the difference in performance between the schemes is not so great as to obsolete DMFDSFV. The second half of the dissertation develops a local, compact, anisotropic unstructured mesh adaption scheme in conjunction with the multi-dimensional upwind solver, exhibiting a characteristic alignment behavior for scalar problems. This alignment behavior stands in contrast to the curvature clustering nature of the local, anisotropic unstructured adaption strategy based upon a posteriori error estimation that is used for comparison. The characteristic alignment is most pronounced for linear advection, with reduced improvement seen for the more complex non-linear advection and advection-diffusion cases. The adaption strategy is extended to the two-dimensional and axisymmetric Navier-Stokes equations of motion through the concept of fluctuation minimization. The system test case for the adaption strategy is a sting mounted capsule at Mach-10 wind tunnel conditions, considered in both two-dimensional and axisymmetric configurations. For this complex flowfield the adaption results are disappointing since feature alignment does not emerge from the local operations. Aggressive adaption is shown to result in a loss of robustness for the solver, particularly in the bow shock/stagnation point interaction region. Reducing the adaption strength maintains solution robustness but fails to produce significant improvement in the surface heat transfer predictions.

Wood, William Alfred, III

151

Overview of NASA Multi-dimensional Stirling Convertor Code Development and Validation Effort  

NASA Technical Reports Server (NTRS)

A NASA grant has been awarded to Cleveland State University (CSU) to develop a multi-dimensional (multi-D) Stirling computer code with the goals of improving loss predictions and identifying component areas for improvements. The University of Minnesota (UMN) and Gedeon Associates are teamed with CSU. Development of test rigs at UMN and CSU and validation of the code against test data are part of the effort. The one-dimensional (1-D) Stirling codes used for design and performance prediction do not rigorously model regions of the working space where abrupt changes in flow area occur (such as manifolds and other transitions between components). Certain hardware experiences have demonstrated large performance gains by varying manifolds and heat exchanger designs to improve flow distributions in the heat exchangers. 1-D codes were not able to predict these performance gains. An accurate multi-D code should improve understanding of the effects of area changes along the main flow axis, sensitivity of performance to slight changes in internal geometry, and, in general, the understanding of various internal thermodynamic losses. The commercial CFD-ACE code has been chosen for development of the multi-D code. This 2-D/3-D code has highly developed pre- and post-processors, and moving boundary capability. Preliminary attempts at validation of CFD-ACE models of MIT gas spring and "two space" test rigs were encouraging. Also, CSU's simulations of the UMN oscillating-flow fig compare well with flow visualization results from UMN. A complementary Department of Energy (DOE) Regenerator Research effort is aiding in development of regenerator matrix models that will be used in the multi-D Stirling code. This paper reports on the progress and challenges of this

Tew, Roy C.; Cairelli, James E.; Ibrahim, Mounir B.; Simon, Terrence W.; Gedeon, David

2002-01-01

152

Multi-dimensional Conjunctive Operation Rule for the Water Supply System  

NASA Astrophysics Data System (ADS)

In recent years, with the increment of floods and droughts, not only in numbers but also in intensities, floods were severer during the wet season and the droughts were more serious during the dry season. In order to reduce their impact on agriculture, industry, and even human being, the conjunctive use of surface water and groundwater has been paid much attention and become a new direction for the future research. Traditionally, the reservoir operation usually follows the operation rule curve to satisfy the water demand and considers only water levels at the reservoirs and time series. The strategy used in the conjunctive-use management model is that the water demand is first satisfied with the reservoirs operated based on the rule curves, and the deficit between demand and supply, if exists, is provided by the groundwater. In this study, we propose a new operation rule, named multi-dimensional conjunctive operation rule curve (MCORC), which is extended from the concept of reservoir operation rule curve. The MCORC is a three-dimensional curve and is applied to both surface water and groundwater. Three sets of parameters, water levels and the supply percentage at reservoirs, groundwater levels and the supply percentage, and time series, are considered simultaneously in the curve. The zonation method and heuristic algorithm are applied to optimize the curve subject to the constraints of the reservoir operation rules and the safety yield of groundwater. The proposed conjunctive operation rule was applied to the water supply system which is analogue to the area in northern Taiwan. The results showed that the MCORC could increase the efficiency of water use and reduce the risk of serious water deficits.

Chiu, Y.; Tan, C. A.; CHEN, Y.; Tung, C.

2011-12-01

153

Scaling Analysis of On-Chip Power Grid Voltage Variations in Nanometer Scale ULSI  

E-print Network

significant amount of skew which in turn degrades the signal integrity. Key words: technology scaling, powerScaling Analysis of On-Chip Power Grid Voltage Variations in Nanometer Scale ULSI AMIR H. AJAMI, 1 analysis of the power supply distribution network voltage drop in DSM technologies. The effects of chip

Pedram, Massoud

154

Multi-dimensional analysis of hdl: an approach to understanding atherogenic hdl  

E-print Network

-propane sulfonate CM Chylomicrons CsBiY Cesium bismuth ethylenediaminetetraacetic acid Cs 2 CdY Dicesium cadmium ethylenediaminetetraacetic acid CAD Coronary artery disease DGU Density gradient ultracentrifugation DMSO Dimethyl sulfoxide...-7.................................. 45 9 The Linear Relationship of Concentration, Density, and Refractive Index for Cs 2 CdY ....................................................................................... 52 10 Plot of ln(Density) vs. Coordinate 2 for 0.2000M...

Johnson, Jr., Jeffery Devoyne

2009-05-15

155

Induction of amyloidogenicity in wild type HEWL by a dialdehyde: analysis involving multi dimensional approach.  

PubMed

Physiological conditions corresponding to oxidative stress deplete the level of enzyme glyoxalase, facilitating a hike in the serum concentration of glyoxal. Simulating an elevated in vivo level of glyoxal, we tested (50%, v/v) concentration of glyoxal to interact with HEWL. Initially, docking study revealed that glyoxal binds in the hydrophobic core of the enzyme. The interaction between the dialdehyde (glyoxal) and the enzyme (HEWL) followed a three step transition involving pre-molten and molten globule states formed on days 7 and 15 of incubation respectively, which were characterised by an increase in the ANS fluorescence intensity compared to the native state. These molten globule states upon further incubation on day 20 resulted in the formation of aggregates which were characterised by an increase in ThT fluorescence intensity, red shift in Congo red absorbance, negative ellipticity peak at 217 nm in the far-UV CD and the loss of signals at 284, 290 and 294 nm in the near-UV CD spectra. Finally, TEM confirmed the authenticity of lysozyme fibril formation by displaying rod like fibrillar structure. PMID:24291768

Fazili, Naveed Ahmad; Bhat, Waseem Feeroze; Naeem, Aabgeena

2014-03-01

156

A Visualization Environment for Fused Multi-dimensional Data Analysis and Navigation in Remote Sensing Applications  

E-print Network

of multi- spectral infrared imagery (Gove et. al., 1996), night vision applications (Aguilar et. al., 1998) and multi- sensor fusion (Ross et. al., 2000), is based on models of color vision in humans and primates of data untapped. Also, some subtle differences between images could be missed. Later, false color

Garrett, Aaron

157

Collection and Analysis of Multi-dimensional Network Data for Opportunistic Networking Research  

E-print Network

networks, or communication, but not all three combined. In this paper we analyze two datasets comprising of relationships on a pairwise level and analyze how the network structures compare to each other. Keywords Preprint submitted to Elsevier April 21, 2012 #12;WiFi. Nodes take profit of communication opportunities

Gesbert, David

158

Symbols of Diaspora Jewish identity: An international survey and multi-dimensional analysis  

Microsoft Academic Search

Symbols are important in representing religious and ethnic identity, particularly in the postmodern age. Using a case study of Jewish adolescents, this article explores the use of symbols in expressing identity. A structural typology of symbols is developed, based on responses to a list of 20 symbols of Jewish identity by over 40,000 Jewish youth from around the world, who

Erik H. Cohen

2008-01-01

159

FlowCube: Constructuing RFID FlowCubes for MultiDimensional Analysis of Commodity Flows  

Microsoft Academic Search

With the advent of RFID (Radio Frequency Identiflcation) technology, manufacturers, distributors, and retailers will be able to track the movement of individual objects throughout the supply chain. The volume of data generated by a typical RFID application will be enormous as each item will gen- erate a complete history of all the individual locations that it occupied at every point

Hector Gonzalez; Jiawei Han; Xiaolei Li

2006-01-01

160

Multi-dimensional forward modeling of frequency-domain helicopter-borne electromagnetic data  

NASA Astrophysics Data System (ADS)

Helicopter-borne frequency-domain electromagnetic (HEM) surveys are used for fast high-resolution, three-dimensional (3-D) resistivity mapping. Nevertheless, 3-D modeling and inversion of an entire HEM data set is in many cases impractical and, therefore, interpretation is commonly based on one-dimensional (1-D) modeling and inversion tools. Such an approach is valid for environments with horizontally layered targets and for groundwater applications but there are areas of higher dimension that are not recovered correctly applying 1-D methods. The focus of this work is the multi-dimensional forward modeling. As there is no analytic solution to verify (or falsify) the obtained numerical solutions, comparison with 1-D values as well as amongst various two-dimensional (2-D) and 3-D codes is essential. At the center of a large structure (a few hundred meters edge length) and above the background structure in some distance to the anomaly 2-D and 3-D values should match the 1-D solution. Higher dimensional conditions are present at the edges of the anomaly and, therefore, only a comparison of different 2-D and 3-D codes gives an indication of the reliability of the solution. The more codes - especially if based on different methods and/or written by different programmers - agree the more reliable is the obtained synthetic data set. Very simple structures such as a conductive or resistive block embedded in a homogeneous or layered half-space without any topography and using a constant sensor height were chosen to calculate synthetic data. For the comparison one finite element 2-D code and numerous 3-D codes, which are based on finite difference, finite element and integral equation approaches, were applied. Preliminary results of the comparison will be shown and discussed. Additionally, challenges that arose from this comparative study will be addressed and further steps to approach more realistic field data settings for forward modeling will be discussed. As the driving engine of an inversion algorithm is its forward solver, applying inversion codes to HEM data is only sensible once the forward modeling results are reliable (and their limits and weaknesses are known and manageable).

Miensopust, M.; Siemon, B.; Börner, R.; Ansari, S.

2013-12-01

161

Secular increase of the Astronomical Unit and perihelion precessions as tests of the Dvali-Gabadadze-Porrati multi-dimensional braneworld scenario  

E-print Network

An unexpected secular increase of the Astronomical Unit, the length scale of the Solar System, has recently been reported by three different research groups (Krasinsky and Brumberg, Pitjeva, Standish). The latest JPL measurements amount to 7+-2 m cy^-1. At present, there are no explanations able to accommodate such an observed phenomenon, neither in the realm of classical physics nor in the usual four-dimensional framework of the Einsteinian General Relativity. The Dvali-Gabadadze-Porrati braneworld scenario, which is a multi-dimensional model of gravity aimed to the explanation of the observed cosmic acceleration without dark energy, predicts, among other things, a perihelion secular shift, due to Lue and Starkman, of 5 10^-4 arcsec cy^-1 for all the planets of the Solar System. It yields a variation of about 6 m cy^-1 for the Earth-Sun distance which is compatible at 1-sigma level with the observed rate of the Astronomical Unit. The recently measured corrections to the secular motions of the perihelia of the inner planets of the Solar System are in agreement, at 1-sigma level, with the predicted value of the Lue-Starkman effect for Mercury and Mars and at 2-sigma level for the Earth.

Lorenzo Iorio

2005-08-11

162

Quantitative Analysis of Scale of Aeromagnetic Data Raises Questions About Geologic-Map Scale  

Microsoft Academic Search

   A recently published study has shown that small-scale geologic map data can reproduce mineral assessments made with considerably\\u000a larger scale data. This result contradicts conventional wisdom about the importance of scale in mineral exploration, at least\\u000a for regional studies. In order to formally investigate aspects of scale, a weights-of-evidence analysis using known gold occurrences\\u000a and deposits in the Central Lapland

Vesa Nykänen; Gary L. Raines

2006-01-01

163

Dynamical scaling analysis of plant callus growth  

NASA Astrophysics Data System (ADS)

We present experimental results for the dynamical scaling properties of the development of plant calli. We have assayed two different species of plant calli, Brassica oleracea and Brassica rapa, under different growth conditions, and show that their dynamical scalings share a universality class. From a theoretical point of view, we introduce a scaling hypothesis for systems whose size evolves in time. We expect our work to be relevant for the understanding and characterization of other systems that undergo growth due to cell division and differentiation, such as, for example, tumor development.

Galeano, J.; Buceta, J.; Juarez, K.; Pumariño, B.; de la Torre, J.; Iriondo, J. M.

2003-07-01

164

Minimum Sample Size Requirements for Mokken Scale Analysis  

ERIC Educational Resources Information Center

An automated item selection procedure in Mokken scale analysis partitions a set of items into one or more Mokken scales, if the data allow. Two algorithms are available that pursue the same goal of selecting Mokken scales of maximum length: Mokken's original automated item selection procedure (AISP) and a genetic algorithm (GA). Minimum…

Straat, J. Hendrik; van der Ark, L. Andries; Sijtsma, Klaas

2014-01-01

165

Convective scale weather analysis and forecasting  

NASA Technical Reports Server (NTRS)

How satellite data can be used to improve insight into the mesoscale behavior of the atmosphere is demonstrated with emphasis on the GOES-VAS sounding and image data. This geostationary satellite has the unique ability to observe frequently the atmosphere (sounders) and its cloud cover (visible and infrared) from the synoptic scale down to the cloud scale. These uniformly calibrated data sets can be combined with conventional data to reveal many of the features important in mesoscale weather development and evolution.

Purdom, J. F. W.

1984-01-01

166

Large-Scale Analysis for Interactive Media Consumption  

E-print Network

Chapter 1 Large-Scale Analysis for Interactive Media Consumption David Gibbon1 , Andrea Basso1 and enabling ways. A brief 1 #12;2CHAPTER 1. LARGE-SCALE ANALYSIS FOR INTERACTIVE MEDIA CONSUMPTION synopsis interests. New mobile and IP consumption environments have emerged with the promise of ubiquitous delivery

Fisher, Kathleen

167

Multi-Dimensional, Mesoscopic Monte Carlo Simulations of Inhomogeneous Reaction-Drift-Diffusion Systems on Graphics-Processing Units  

PubMed Central

For many biological applications, a macroscopic (deterministic) treatment of reaction-drift-diffusion systems is insufficient. Instead, one has to properly handle the stochastic nature of the problem and generate true sample paths of the underlying probability distribution. Unfortunately, stochastic algorithms are computationally expensive and, in most cases, the large number of participating particles renders the relevant parameter regimes inaccessible. In an attempt to address this problem we present a genuine stochastic, multi-dimensional algorithm that solves the inhomogeneous, non-linear, drift-diffusion problem on a mesoscopic level. Our method improves on existing implementations in being multi-dimensional and handling inhomogeneous drift and diffusion. The algorithm is well suited for an implementation on data-parallel hardware architectures such as general-purpose graphics processing units (GPUs). We integrate the method into an operator-splitting approach that decouples chemical reactions from the spatial evolution. We demonstrate the validity and applicability of our algorithm with a comprehensive suite of standard test problems that also serve to quantify the numerical accuracy of the method. We provide a freely available, fully functional GPU implementation. Integration into Inchman, a user-friendly web service, that allows researchers to perform parallel simulations of reaction-drift-diffusion systems on GPU clusters is underway. PMID:22506001

Vigelius, Matthias; Meyer, Bernd

2012-01-01

168

Scientific design of Purdue University Multi-Dimensional Integral Test Assembly (PUMA) for GE SBWR  

SciTech Connect

The scaled facility design was based on the three level scaling method; the first level is based on the well established approach obtained from the integral response function, namely integral scaling. This level insures that the stead-state as well as dynamic characteristics of the loops are scaled properly. The second level scaling is for the boundary flow of mass and energy between components; this insures that the flow and inventory are scaled correctly. The third level is focused on key local phenomena and constitutive relations. The facility has 1/4 height and 1/100 area ratio scaling; this corresponds to the volume scale of 1/400. Power scaling is 1/200 based on the integral scaling. The time will run twice faster in the model as predicted by the present scaling method. PUMA is scaled for full pressure and is intended to operate at and below 150 psia following scram. The facility models all the major components of SBWR (Simplified Boiling Water Reactor), safety and non-safety systems of importance to the transients. The model component designs and detailed instrumentations are presented in this report.

Ishii, M.; Ravankar, S.T.; Dowlati, R. [Purdue Univ., Lafayette, IN (United States). School of Nuclear Engineering] [and others

1996-04-01

169

Assessment of RELAP5-3D multi-dimensional component model using data from LOFT Test L2-5  

SciTech Connect

The capability of the RELAP5-3D computer code to perform multi-dimensional analysis of a pressurized water reactor (PWR) was assessed using data from the Loss-of-Fluid Test (LOFT) L2-5 experiment. The LOFT facility was a 50 MW PWR that was designed to simulate the response of a commercial PWR during a loss-of-coolant accident (LOCA). Test L2-5 simulated a 200% double-ended cold leg break with an immediate primary coolant pump trip. A three-dimensional model of the LOFT reactor vessel was developed. Calculations of the LOFT L21-5 experiment were performed using the RELAP5-3D computer code. The calculations simulated the blowdown, refill, and reflood portions of the transient. The calculated thermal-hydraulic response of the primary coolant system was generally in reasonable agreement with the test. The calculated results were also generally as good as or better than those obtained previously with RELAP5/MOD3.

Davis, C.B.

1998-07-01

170

A semi-parametric approach to estimate risk functions associated with multi-dimensional exposure profiles: application to smoking and lung cancer  

PubMed Central

Background A common characteristic of environmental epidemiology is the multi-dimensional aspect of exposure patterns, frequently reduced to a cumulative exposure for simplicity of analysis. By adopting a flexible Bayesian clustering approach, we explore the risk function linking exposure history to disease. This approach is applied here to study the relationship between different smoking characteristics and lung cancer in the framework of a population based case control study. Methods Our study includes 4658 males (1995 cases, 2663 controls) with full smoking history (intensity, duration, time since cessation, pack-years) from the ICARE multi-centre study conducted from 2001-2007. We extend Bayesian clustering techniques to explore predictive risk surfaces for covariate profiles of interest. Results We were able to partition the population into 12 clusters with different smoking profiles and lung cancer risk. Our results confirm that when compared to intensity, duration is the predominant driver of risk. On the other hand, using pack-years of cigarette smoking as a single summary leads to a considerable loss of information. Conclusions Our method estimates a disease risk associated to a specific exposure profile by robustly accounting for the different dimensions of exposure and will be helpful in general to give further insight into the effect of exposures that are accumulated through different time patterns. PMID:24152389

2013-01-01

171

Longitudinal Network Analysis Using Multidimensional Scaling.  

ERIC Educational Resources Information Center

The Galileo System, a variant of metric multidimensional scaling, is used in this paper to analyze over-time changes in social networks. The paper first discusses the theoretical necessity for the use of this procedure and the methodological problems associated with its use. It then examines the air traffic network among 31 major cities in the…

Barnett, George A.; Palmer, Mark T.

172

Analysis of a municipal wastewater treatment plant using a neural network-based pattern analysis  

USGS Publications Warehouse

This paper addresses the problem of how to capture the complex relationships that exist between process variables and to diagnose the dynamic behaviour of a municipal wastewater treatment plant (WTP). Due to the complex biological reaction mechanisms, the highly time-varying, and multivariable aspects of the real WTP, the diagnosis of the WTP are still difficult in practice. The application of intelligent techniques, which can analyse the multi-dimensional process data using a sophisticated visualisation technique, can be useful for analysing and diagnosing the activated-sludge WTP. In this paper, the Kohonen Self-Organising Feature Maps (KSOFM) neural network is applied to analyse the multi-dimensional process data, and to diagnose the inter-relationship of the process variables in a real activated-sludge WTP. By using component planes, some detailed local relationships between the process variables, e.g., responses of the process variables under different operating conditions, as well as the global information is discovered. The operating condition and the inter-relationship among the process variables in the WTP have been diagnosed and extracted by the information obtained from the clustering analysis of the maps. It is concluded that the KSOFM technique provides an effective analysing and diagnosing tool to understand the system behaviour and to extract knowledge contained in multi-dimensional data of a large-scale WTP. ?? 2003 Elsevier Science Ltd. All rights reserved.

Hong, Y. -S. T.; Rosen, M. R.; Bhamidimarri, R.

2003-01-01

173

Local variance for multi-scale analysis in geomorphometry.  

PubMed

Increasing availability of high resolution Digital Elevation Models (DEMs) is leading to a paradigm shift regarding scale issues in geomorphometry, prompting new solutions to cope with multi-scale analysis and detection of characteristic scales. We tested the suitability of the local variance (LV) method, originally developed for image analysis, for multi-scale analysis in geomorphometry. The method consists of: 1) up-scaling land-surface parameters derived from a DEM; 2) calculating LV as the average standard deviation (SD) within a 3 × 3 moving window for each scale level; 3) calculating the rate of change of LV (ROC-LV) from one level to another, and 4) plotting values so obtained against scale levels. We interpreted peaks in the ROC-LV graphs as markers of scale levels where cells or segments match types of pattern elements characterized by (relatively) equal degrees of homogeneity. The proposed method has been applied to LiDAR DEMs in two test areas different in terms of roughness: low relief and mountainous, respectively. For each test area, scale levels for slope gradient, plan, and profile curvatures were produced at constant increments with either resampling (cell-based) or image segmentation (object-based). Visual assessment revealed homogeneous areas that convincingly associate into patterns of land-surface parameters well differentiated across scales. We found that the LV method performed better on scale levels generated through segmentation as compared to up-scaling through resampling. The results indicate that coupling multi-scale pattern analysis with delineation of morphometric primitives is possible. This approach could be further used for developing hierarchical classifications of landform elements. PMID:21779138

Dr?gu?, Lucian; Eisank, Clemens; Strasser, Thomas

2011-07-15

174

Local variance for multi-scale analysis in geomorphometry  

PubMed Central

Increasing availability of high resolution Digital Elevation Models (DEMs) is leading to a paradigm shift regarding scale issues in geomorphometry, prompting new solutions to cope with multi-scale analysis and detection of characteristic scales. We tested the suitability of the local variance (LV) method, originally developed for image analysis, for multi-scale analysis in geomorphometry. The method consists of: 1) up-scaling land-surface parameters derived from a DEM; 2) calculating LV as the average standard deviation (SD) within a 3 × 3 moving window for each scale level; 3) calculating the rate of change of LV (ROC-LV) from one level to another, and 4) plotting values so obtained against scale levels. We interpreted peaks in the ROC-LV graphs as markers of scale levels where cells or segments match types of pattern elements characterized by (relatively) equal degrees of homogeneity. The proposed method has been applied to LiDAR DEMs in two test areas different in terms of roughness: low relief and mountainous, respectively. For each test area, scale levels for slope gradient, plan, and profile curvatures were produced at constant increments with either resampling (cell-based) or image segmentation (object-based). Visual assessment revealed homogeneous areas that convincingly associate into patterns of land-surface parameters well differentiated across scales. We found that the LV method performed better on scale levels generated through segmentation as compared to up-scaling through resampling. The results indicate that coupling multi-scale pattern analysis with delineation of morphometric primitives is possible. This approach could be further used for developing hierarchical classifications of landform elements. PMID:21779138

Dragut, Lucian; Eisank, Clemens; Strasser, Thomas

2011-01-01

175

Genetic Analysis of Invasive Plant Populations at Different Spatial Scales  

Microsoft Academic Search

Measuring genetic diversity requires selection of a spatial scale of analysis. Different levels of genetic structuring are\\u000a revealed at different spatial scales, however, and the relative importance of factors driving genetic structuring varies along\\u000a the spatial scale continuum. Unequal gene flow is a major factor determining genetic structure in plant populations at the\\u000a local level, while the effect of selection

Sarah Ward

2006-01-01

176

The Attitudes to Ageing Questionnaire: Mokken Scaling Analysis  

PubMed Central

Background Hierarchical scales are useful in understanding the structure of underlying latent traits in many questionnaires. The Attitudes to Ageing Questionnaire (AAQ) explored the attitudes to ageing of older people themselves, and originally described three distinct subscales: (1) Psychosocial Loss (2) Physical Change and (3) Psychological Growth. This study aimed to use Mokken analysis, a method of Item Response Theory, to test for hierarchies within the AAQ and to explore how these relate to underlying latent traits. Methods Participants in a longitudinal cohort study, the Lothian Birth Cohort 1936, completed a cross-sectional postal survey. Data from 802 participants were analysed using Mokken Scaling analysis. These results were compared with factor analysis using exploratory structural equation modelling. Results Participants were 51.6% male, mean age 74.0 years (SD 0.28). Three scales were identified from 18 of the 24 items: two weak Mokken scales and one moderate Mokken scale. (1) ‘Vitality’ contained a combination of items from all three previously determined factors of the AAQ, with a hierarchy from physical to psychosocial; (2) ‘Legacy’ contained items exclusively from the Psychological Growth scale, with a hierarchy from individual contributions to passing things on; (3) ‘Exclusion’ contained items from the Psychosocial Loss scale, with a hierarchy from general to specific instances. All of the scales were reliable and statistically significant with ‘Legacy’ showing invariant item ordering. The scales correlate as expected with personality, anxiety and depression. Exploratory SEM mostly confirmed the original factor structure. Conclusions The concurrent use of factor analysis and Mokken scaling provides additional information about the AAQ. The previously-described factor structure is mostly confirmed. Mokken scaling identifies a new factor relating to vitality, and a hierarchy of responses within three separate scales, referring to vitality, legacy and exclusion. This shows what older people themselves consider important regarding their own ageing. PMID:24892302

Shenkin, Susan D.; Watson, Roger; Laidlaw, Ken; Starr, John M.; Deary, Ian J.

2014-01-01

177

Multi-scale analysis of heavy rainfall systems  

NASA Astrophysics Data System (ADS)

The aim of this work is to study the cross-scale interactions with focus on mesoscale convective system. A multi-scale analysis of a heavy rainfall event is carried out by dividing the responsible systems into large, middle and small scales. The three distinctive scales correspond respectively to upper- and low-level jets, meso-scale convective systems and convective cells. The governing equations for the three scales are derived and then simplified to their bare essence to illustrate the cross-scale interactions. In particular, the cross-scale transfers of momentum and heat are retained in the equations to illustrate the interactions between the large and small scale motions with the mesoscale system. WRF has been used to simulate a heavy rainfall event in southeast China and the model results are used to test the theory of the multi-scale interactions. Overall, the theory shows a plausible mechanism that the meso-scale convective system is responsible for the vertical momentum transfer from the upper level jet to the lower level jet which maintains the low-level positive vorticity of the convective system. The low-level jet also carries large quantities of moisture from the South China Sea to Southeast China, which are necessary for small scale convections.

TSUI, Chi Yan; Shao, Yaping

2014-05-01

178

High-Order Semi-Discrete Central-Upwind Schemes for Multi-Dimensional Hamilton-Jacobi Equations  

NASA Technical Reports Server (NTRS)

We present the first fifth order, semi-discrete central upwind method for approximating solutions of multi-dimensional Hamilton-Jacobi equations. Unlike most of the commonly used high order upwind schemes, our scheme is formulated as a Godunov-type scheme. The scheme is based on the fluxes of Kurganov-Tadmor and Kurganov-Tadmor-Petrova, and is derived for an arbitrary number of space dimensions. A theorem establishing the monotonicity of these fluxes is provided. The spacial discretization is based on a weighted essentially non-oscillatory reconstruction of the derivative. The accuracy and stability properties of our scheme are demonstrated in a variety of examples. A comparison between our method and other fifth-order schemes for Hamilton-Jacobi equations shows that our method exhibits smaller errors without any increase in the complexity of the computations.

Bryson, Steve; Levy, Doron; Biegel, Bryan (Technical Monitor)

2002-01-01

179

Confirmatory factor analysis of the social anxiety scale for children  

Microsoft Academic Search

A confirmatory factor analysis was performed on responses from 436 (234 female, 202 male) primary school students to the La Greca et al. (1988) Social Anxiety Scale for Children (SASC). While loadings for one SASC item were ambiguous, results generally supported the original two-factor (Fear of Negative Evaluation and Social Anxiety and Distress) scale structure. Internal consistencies for the two

Elaine Chapman

180

ScaleMirror: A Pervasive Device to Aid Weight Analysis  

E-print Network

ScaleMirror: A Pervasive Device to Aid Weight Analysis Abstract As today's fast paced environment and control weight gain. With the advent of pervasive and ubiquitous computing, there are new opportunities and creation of ScaleMirror; a prototype pervasive device to help users monitor their weight. This awareness

Connelly, Kay

181

Mokken Scale Analysis for Dichotomous Items Using Marginal Models  

ERIC Educational Resources Information Center

Scalability coefficients play an important role in Mokken scale analysis. For a set of items, scalability coefficients have been defined for each pair of items, for each individual item, and for the entire scale. Hypothesis testing with respect to these scalability coefficients has not been fully developed. This study introduces marginal modelling…

van der Ark, L. Andries; Croon, Marcel A.; Sijtsma, Klaas

2008-01-01

182

A multi-dimensional microfluidic platform recapitulating chemotactic and morphogenic chemical gradients  

E-print Network

The requirement that individual cells be able to communicate with one another over a range of length scales is a fundamental prerequisite for the evolution of multicellular organisms. Often diffusible chemical molecules ...

Amadi, Ovid Charles

2013-01-01

183

Metal analysis of scales taken from Arctic grayling.  

PubMed

This study examined concentrations of metals in fish scales taken from Arctic grayling using laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS). The purpose was to assess whether scale metal concentrations reflected whole muscle metal concentrations and whether the spatial distribution of metals within an individual scale varied among the growth annuli of the scales. Ten elements (Mg, Ca, Ni, Zn, As, Se, Cd, Sb, Hg, and Pb) were measured in 10 to 16 ablation sites (5 microm radius) on each scale sample from Arctic grayling (Thymallus arcticus) (n = 10 fish). Ca, Mg, and Zn were at physiological levels in all scale samples. Se, Hg, and As were also detected in all scale samples. Only Cd was below detection limits of the LA-ICPMS for all samples, but some of the samples were below detection limits for Sb, Pb, and Ni. The mean scale concentrations for Se, Hg, and Pb were not significantly different from the muscle concentrations and individual fish values were within fourfold of each other. Cd was not detected in either muscle or scale tissue, whereas Sb was detected at low levels in some scale samples but not in any of the muscle samples. Similarly, As was detected in all scale samples but not in muscle, and Ni was detected almost all scale samples but only in one of the muscle samples. Therefore, there were good qualitative and quantitative agreements between the metal concentrations in scale and muscle tissues, with LA-ICPMS analysis of scales appearing to be a more sensitive method of detecting the body burden of Ni and As when compared with muscle tissue. Correlation analyses, performed for Pb, Hg, and Se concentrations, revealed that the scale concentrations for these three metals generally exceeded those of the muscle at low muscle concentrations. The LA-ICPMS analysis of scales had the capability to resolve significant spatial differences in metal concentrations within a fish scale. We conclude that metal analysis of fish scales using LA-ICPMS shows considerable promise as a nonlethal analytical tool to assess metal body burden in fish that could possibly generate a historic record of metal exposure. However, comprehensive validation experiments are still needed. PMID:11031313

Farrell, A P; Hodaly, A H; Wang, S

2000-11-01

184

Large scale analysis of signal reachability  

PubMed Central

Motivation: Major disorders, such as leukemia, have been shown to alter the transcription of genes. Understanding how gene regulation is affected by such aberrations is of utmost importance. One promising strategy toward this objective is to compute whether signals can reach to the transcription factors through the transcription regulatory network (TRN). Due to the uncertainty of the regulatory interactions, this is a #P-complete problem and thus solving it for very large TRNs remains to be a challenge. Results: We develop a novel and scalable method to compute the probability that a signal originating at any given set of source genes can arrive at any given set of target genes (i.e., transcription factors) when the topology of the underlying signaling network is uncertain. Our method tackles this problem for large networks while providing a provably accurate result. Our method follows a divide-and-conquer strategy. We break down the given network into a sequence of non-overlapping subnetworks such that reachability can be computed autonomously and sequentially on each subnetwork. We represent each interaction using a small polynomial. The product of these polynomials express different scenarios when a signal can or cannot reach to target genes from the source genes. We introduce polynomial collapsing operators for each subnetwork. These operators reduce the size of the resulting polynomial and thus the computational complexity dramatically. We show that our method scales to entire human regulatory networks in only seconds, while the existing methods fail beyond a few tens of genes and interactions. We demonstrate that our method can successfully characterize key reachability characteristics of the entire transcriptions regulatory networks of patients affected by eight different subtypes of leukemia, as well as those from healthy control samples. Availability: All the datasets and code used in this article are available at bioinformatics.cise.ufl.edu/PReach/scalable.htm. Contact: atodor@cise.ufl.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:24932011

Todor, Andrei; Gabr, Haitham; Dobra, Alin; Kahveci, Tamer

2014-01-01

185

A Cross-Cultural Comparison of Singaporean and Taiwanese Eighth Graders' Science Learning Self-Efficacy from a Multi-Dimensional Perspective  

ERIC Educational Resources Information Center

Due to the scarcity of cross-cultural comparative studies in exploring students' self-efficacy in science learning, this study attempted to develop a multi-dimensional science learning self-efficacy (SLSE) instrument to measure 316 Singaporean and 303 Taiwanese eighth graders' SLSE and further to examine the differences between the two…

Lin, Tzung-Jin; Tan, Aik Ling; Tsai, Chin-Chung

2013-01-01

186

Uncovering Cross-Dimension Group Structures in Multi-Dimensional Networks With the proliferation of Web 2.0 and social networking sites, peo-  

E-print Network

other easily through various social media. For instance, popular sites like Del.icio.us, Flickr, and You-dimension group structures with group members focusing on similar topics. It is challenging to effectivelyUncovering Cross-Dimension Group Structures in Multi-Dimensional Networks Lei Tang Huan Liu

Liu, Huan

187

Evidence for a Multi-Dimensional Latent Structural Model of Externalizing Disorders  

ERIC Educational Resources Information Center

Strong associations between conduct disorder (CD), antisocial personality disorder (ASPD) and substance use disorders (SUD) seem to reflect a general vulnerability to externalizing behaviors. Recent studies have characterized this vulnerability on a continuous scale, rather than as distinct categories, suggesting that the revision of the…

Witkiewitz, Katie; King, Kevin; McMahon, Robert J.; Wu, Johnny; Luk, Jeremy; Bierman, Karen L.; Coie, John D.; Dodge, Kenneth A.; Greenberg, Mark T.; Lochman, John E.; Pinderhughes, Ellen E.

2013-01-01

188

ON THE RECURRENCE PLOT ANALYSIS METHOD BEHAVIOUR UNDER SCALING TRANSFORM  

E-print Network

ON THE RECURRENCE PLOT ANALYSIS METHOD BEHAVIOUR UNDER SCALING TRANSFORM F.-M. Birleanua,d , C, University of Pitesti, Romania ABSTRACT In the last decade, the applications of the recurrence plot analy the behaviour of the recurrence plot analysis method in the context of analyzing some finite duration signals

Paris-Sud XI, Université de

189

Honeycomb: Visual Analysis of Large Scale Social Networks  

NASA Astrophysics Data System (ADS)

The rise in the use of social network sites allows us to collect large amounts of user reported data on social structures and analysis of this data could provide useful insights for many of the social sciences. This analysis is typically the domain of Social Network Analysis, and visualization of these structures often proves invaluable in understanding them. However, currently available visual analysis tools are not very well suited to handle the massive scale of this network data, and often resolve to displaying small ego networks or heavily abstracted networks. In this paper, we present Honeycomb, a visualization tool that is able to deal with much larger scale data (with millions of connections), which we illustrate by using a large scale corporate social networking site as an example. Additionally, we introduce a new probability based network metric to guide users to potentially interesting or anomalous patterns and discuss lessons learned during design and implementation.

van Ham, Frank; Schulz, Hans-Jörg; Dimicco, Joan M.

190

On Multi-dimensional Steady Subsonic Flows Determined by Physical Boundary Conditions  

NASA Astrophysics Data System (ADS)

In this thesis, we investigate an inflow-outflow problem for subsonic gas flows in a nozzle with finite length, aiming at finding intrinsic (physically acceptable) boundary conditions on upstream and downstream. We first characterize a set of physical boundary conditions that ensure the existence and uniqueness of a subsonic irrotational flow in a rectangle. Our results show that suppose we prescribe the horizontal incoming flow angle at the inlet and an appropriate pressure at the exit, there exists two positive constants m 0 and m1 with m0 < m1, such that a global subsonic irrotational flow exists uniquely in the nozzle, provided that the incoming mass flux m ? [m0, m 1). The maximum speed will approach the sonic speed as the mass flux m tends to m1. The new difficulties arise from the nonlocal term involved in the mass flux and the pressure condition at the exit. We first introduce an auxiliary problem with the Bernoulli's constant as a parameter to localize the nonlocal term and then establish a monotonic relation between the mass flux and the Bernoulli's constant to recover the original problem. To deal with the loss of obliqueness induced by the pressure condition at the exit, we employ the formulation in terms of the angular velocity and the density. A Moser iteration is applied to obtain the Linfinity estimate of the angular velocity, which guarantees that the flow possesses a positive horizontal velocity in the whole nozzle. As a continuation, we investigate the influence of the incoming flow angle and the geometry structure of the nozzle walls on subsonic flows in a finitely long curved nozzle. It turns out to be interesting that the incoming flow angle and the angles of inclination of nozzle walls play the same role as the end pressure. The curvatures of the nozzle walls play an important role. We also extend our results to subsonic Euler flows in the 2-D and 3-D asymmetric cases. Then it comes to the most interesting and difficult case--the 3-D subsonic Euler flow in a bounded nozzle, which is also the essential part of this thesis. The boundary conditions we have imposed in the 2-D case have a natural extension in the 3-D case. These important clues help us a lot to develop a new formulation to get some insights on the coupling structure between hyperbolic and elliptic modes in the Euler equations. The key idea in our new formulation is to use the Bernoulli's law to reduce the dimension of the velocity field by defining new variables (1,b2=u2u 1,b3=u3 u1) and replacing u1 by the Bernoulli's function B through u21=2B-h r1+ b22+b23 . In this way, we can explore the role of the Bernoulli's law in greater depth and hope that may simplify the Euler equations a little bit. We find a new conserved quantity for flows with a constant Bernoulli's function, which behaves like the scaled vorticity in the 2-D case. More surprisingly, a system of new conservation laws can be derived, which is never been observed before, even in the two dimensional case. We employ this formulation to construct a smooth subsonic Euler flow in a rectangular cylinder by assigning the incoming flow angles and the Bernoulli's function at the inlet and the end pressure at the exit, which is also required to be adjacent to some special subsonic states. The same idea can be applied to obtain similar information for the incompressible Euler equations, the self-similar Euler equations, the steady Euler equations with damping, the steady Euler-Poisson equations and the steady Euler-Maxwell equations. Last, we are concerned with the structural stability of some steady subsonic solutions for the Euler-Poisson system. A steady subsonic solution with subsonic background charge is proven to be structurally stable with respect to small perturbations of the background charge, the incoming flow angles and the end pressure, provided the background solution has a low Mach number and a small electric field. The new ingredient in our mathematical analysis is the solvability of a new second order elliptic system supplemented with oblique derivative conditio

Weng, Shangkun

191

Safeguardability analysis for an engineering scale pyroprocess facility  

Microsoft Academic Search

A qualitative safeguardability analysis was undertaken to investigate the safeguards system and draw recommendations for enhancing the performance of the safeguards system for an engineering-scale pyroprocess model facility. The analysis utilized INPRO proliferation resistance (PR) assessment methodologies including diversion pathway analysis. Uranium and transuranic metal (U\\/TRU) products emit high neutrons and gamma-rays, which are strong enough to be detected by

Seong-Kyu Ahn; Hee-Sung Shin; Ho-Dong Kim

2012-01-01

192

Flux Coupling Analysis of Genome-Scale Metabolic Network Reconstructions  

Microsoft Academic Search

In this paper,we introduce the Flux Coupling Finder (FCF) framework for el ucidating the topological and flux connectivity features of genome-scale metabolic networks. The framework is demonstrated on genome-scale metabolic reconstructions of Helicobacter pylori, Escherichia coli,and Saccharomyces cerevisiae. The analysis allows one to determine whether any two metabolic fluxes, v1 and v2,are (1) directionally coupled,if a non-zero flux for v1

Anthony P. Burgard; Evgeni V. Nikolaev; Christophe H. Schilling; Costas D. Maranas

2004-01-01

193

Multi-Scale Unit-Cell Analysis ofMulti-Scale Unit-Cell Analysis of Textile CompositesTextile Composites'' FiniteFinite  

E-print Network

1 Multi-Scale Unit-Cell Analysis ofMulti-Scale Unit-Cell Analysis of Textile CompositesTextile for textile composites to facilitate structural analysis Enhanced understanding of textile composites. 3. Results on fiber-diameter scale 4. Results on textile unit-cell scale #12;3 Research Objectives

Swan Jr., Colby Corson

194

Analysis and modeling of large-scale steam explosion experiments  

SciTech Connect

This paper describes current analysis and modeling results of large-scale steam explosion experiments. For the large-scale experiments, a transient one-dimensional explosion model was developed that can qualitatively predict the trends in the experimental data. The model employs a description of vapor film collapse and subsequent fuel fragmentation by thermal and mechanical means. In addition, a simple empirical explosion model was developed and incorporated into a two-dimensional hydrodynamic computer program. This combination can be used to investigate the two-dimensional characteristics of the propagation and expansion phases for large-scale explosions.

Corradini, M.L.

1982-12-01

195

Multi-Dimensional Quantum Tunneling and Transport Using the Density-Gradient Model  

NASA Technical Reports Server (NTRS)

We show that quantum effects are likely to significantly degrade the performance of MOSFETs (metal oxide semiconductor field effect transistor) as these devices are scaled below 100 nm channel length and 2 nm oxide thickness over the next decade. A general and computationally efficient electronic device model including quantum effects would allow us to monitor and mitigate these effects. Full quantum models are too expensive in multi-dimensions. Using a general but efficient PDE solver called PROPHET, we implemented the density-gradient (DG) quantum correction to the industry-dominant classical drift-diffusion (DD) model. The DG model efficiently includes quantum carrier profile smoothing and tunneling in multi-dimensions and for any electronic device structure. We show that the DG model reduces DD model error from as much as 50% down to a few percent in comparison to thin oxide MOS capacitance measurements. We also show the first DG simulations of gate oxide tunneling and transverse current flow in ultra-scaled MOSFETs. The advantages of rapid model implementation using the PDE solver approach will be demonstrated, as well as the applicability of the DG model to any electronic device structure.

Biegel, Bryan A.; Yu, Zhi-Ping; Ancona, Mario; Rafferty, Conor; Saini, Subhash (Technical Monitor)

1999-01-01

196

Geographical scale effects on the analysis of leptospirosis determinants.  

PubMed

Leptospirosis displays a great diversity of routes of exposure, reservoirs, etiologic agents, and clinical symptoms. It occurs almost worldwide but its pattern of transmission varies depending where it happens. Climate change may increase the number of cases, especially in developing countries, like Brazil. Spatial analysis studies of leptospirosis have highlighted the importance of socioeconomic and environmental context. Hence, the choice of the geographical scale and unit of analysis used in the studies is pivotal, because it restricts the indicators available for the analysis and may bias the results. In this study, we evaluated which environmental and socioeconomic factors, typically used to characterize the risks of leptospirosis transmission, are more relevant at different geographical scales (i.e., regional, municipal, and local). Geographic Information Systems were used for data analysis. Correlations between leptospirosis incidence and several socioeconomic and environmental indicators were calculated at different geographical scales. At the regional scale, the strongest correlations were observed between leptospirosis incidence and the amount of people living in slums, or the percent of the area densely urbanized. At the municipal scale, there were no significant correlations. At the local level, the percent of the area prone to flooding best correlated with leptospirosis incidence. PMID:25310536

Gracie, Renata; Barcellos, Christovam; Magalhães, Mônica; Souza-Santos, Reinaldo; Barrocas, Paulo Rubens Guimarães

2014-01-01

197

Geographical Scale Effects on the Analysis of Leptospirosis Determinants  

PubMed Central

Leptospirosis displays a great diversity of routes of exposure, reservoirs, etiologic agents, and clinical symptoms. It occurs almost worldwide but its pattern of transmission varies depending where it happens. Climate change may increase the number of cases, especially in developing countries, like Brazil. Spatial analysis studies of leptospirosis have highlighted the importance of socioeconomic and environmental context. Hence, the choice of the geographical scale and unit of analysis used in the studies is pivotal, because it restricts the indicators available for the analysis and may bias the results. In this study, we evaluated which environmental and socioeconomic factors, typically used to characterize the risks of leptospirosis transmission, are more relevant at different geographical scales (i.e., regional, municipal, and local). Geographic Information Systems were used for data analysis. Correlations between leptospirosis incidence and several socioeconomic and environmental indicators were calculated at different geographical scales. At the regional scale, the strongest correlations were observed between leptospirosis incidence and the amount of people living in slums, or the percent of the area densely urbanized. At the municipal scale, there were no significant correlations. At the local level, the percent of the area prone to flooding best correlated with leptospirosis incidence. PMID:25310536

Gracie, Renata; Barcellos, Christovam; Magalhaes, Monica; Souza-Santos, Reinaldo; Barrocas, Paulo Rubens Guimaraes

2014-01-01

198

Scale analysis using X-ray microfluorescence and computed radiography  

NASA Astrophysics Data System (ADS)

Scale deposits are the most common and most troublesome damage problems in the oil field and can occur in both production and injection wells. They occur because the minerals in produced water exceed their saturation limit as temperatures and pressures change. Scale can vary in appearance from hard crystalline material to soft, friable material and the deposits can contain other minerals and impurities such as paraffin, salt and iron. In severe conditions, scale creates a significant restriction, or even a plug, in the production tubing. This study was conducted to qualify the elements present in scale samples and quantify the thickness of the scale layer using synchrotron radiation micro-X-ray fluorescence (SR?XRF) and computed radiography (CR) techniques. The SR?XRF results showed that the elements found in the scale samples were strontium, barium, calcium, chromium, sulfur and iron. The CR analysis showed that the thickness of the scale layer was identified and quantified with accuracy. These results can help in the decision making about removing the deposited scale.

Candeias, J. P.; de Oliveira, D. F.; dos Anjos, M. J.; Lopes, R. T.

2014-02-01

199

Multi-dimensional PIC-simulations of parametric instabilities for shock-ignition conditions  

NASA Astrophysics Data System (ADS)

Laser-plasma interaction is investigated for conditions relevant for the shock-ignition (SI) scheme of inertial confinement fusion using two-dimensional particle-in-cell (PIC) simulations of an intense laser beam propagating in a hot, large-scale, non-uniform plasma. The temporal evolution and interdependence of Raman- (SRS), and Brillouin- (SBS), side/backscattering as well as Two-Plasmon-Decay (TPD) are studied. TPD is developing in concomitance with SRS creating a broad spectrum of plasma waves near the quarter-critical density. They are rapidly saturated due to plasma cavitation within a few picoseconds. The hot electron spectrum created by SRS and TPD is relatively soft, limited to energies below one hundred keV.

Riconda, C.; Weber, S.; Klimo, O.; Héron, A.; Tikhonchuk, V. T.

2013-11-01

200

Voice dysfunction in dysarthria: application of the MultiDimensional Voice Program™  

Microsoft Academic Search

Phonatory dysfunction is a frequent component of dysarthria and often is a primary feature noted in clinical assessment. But the vocal impairment can be difficult to assess because (a) the analysis of voice disorder of any kind can be challenging, and (b) the voice disorder in dysarthria often occurs along with other impairments affecting articulation, resonance, and respiration. A promising

R. D. Kent; H. K. Vorperian; J. F. Kent; J. R. Duffy

2003-01-01

201

The Effects of Multi-Dimensional Competition on Education Market Outcomes  

E-print Network

private schools BLS U.S. Bureau of Labor Statistics CBSA Core Based Statistical Area CCD Common Core of Data, National Center for Education Statistics CWI Comparable wage index DEA Data envelopment analysis f.o.b. Free-on-board GMM Generalized... product NCES National Center for Education Statistics OLS Ordinary least squares OMB U.S. Office of Management and Budget vi OSPI Office of Superintendent of Public Instruction, Washington PSS Private School Universe Survey, National Center...

Karakaplan, Mustafa

2012-10-19

202

Basin-scale Modeling of Geological Carbon Sequestration: Model Complexity, Injection Scenario and Sensitivity Analysis  

NASA Astrophysics Data System (ADS)

Geological carbon sequestration can significantly contribute to climate-change mitigation only if it is deployed at a very large scale. This means that injection scenarios must occur, and be analyzed, at the basin scale. Various mathematical models of different complexity may be used to assess the fate of injected CO2 and/or resident brine. These models span the range from multi-dimensional, multi-phase numerical simulators to simple single-phase analytical solutions. In this study, we consider a range of models, all based on vertically-integrated governing equations, to predict the basin-scale pressure response to specific injection scenarios. The Canadian section of the Basal Aquifer is used as a test site to compare the different modeling approaches. The model domain covers an area of approximately 811,000 km2, and the total injection rate is 63 Mt/yr, corresponding to 9 locations where large point sources have been identified. Predicted areas of critical pressure exceedance are used as a comparison metric among the different modeling approaches. Comparison of the results shows that single-phase numerical models may be good enough to predict the pressure response over a large aquifer; however, a simple superposition of semi-analytical or analytical solutions is not sufficiently accurate because spatial variability of formation properties plays an important role in the problem, and these variations are not captured properly with simple superposition. We consider two different injection scenarios: injection at the source locations and injection at locations with more suitable aquifer properties. Results indicate that in formations with significant spatial variability of properties, strong variations in injectivity among the different source locations can be expected, leading to the need to transport the captured CO2 to suitable injection locations, thereby necessitating development of a pipeline network. We also consider the sensitivity of porosity and permeability data, and assess how data uncertainties affect model comparison results.

Huang, X.; Bandilla, K.; Celia, M. A.; Bachu, S.

2013-12-01

203

Stochastic optimization framework (SOF) for computer-optimized design, engineering, and performance of multi-dimensional systems and processes  

NASA Astrophysics Data System (ADS)

Many systems and processes, both natural and artificial, may be described by parameter-driven mathematical and physical models. We introduce a generally applicable Stochastic Optimization Framework (SOF) that can be interfaced to or wrapped around such models to optimize model outcomes by effectively "inverting" them. The Visual and Autonomous Exploration Systems Research Laboratory (http://autonomy.caltech.edu edu) at the California Institute of Technology (Caltech) has long-term experience in the optimization of multi-dimensional systems and processes. Several examples of successful application of a SOF are reviewed and presented, including biochemistry, robotics, device performance, mission design, parameter retrieval, and fractal landscape optimization. Applications of a SOF are manifold, such as in science, engineering, industry, defense & security, and reconnaissance/exploration. Keywords: Multi-parameter optimization, design/performance optimization, gradient-based steepest-descent methods, local minima, global minimum, degeneracy, overlap parameter distribution, fitness function, stochastic optimization framework, Simulated Annealing, Genetic Algorithms, Evolutionary Algorithms, Genetic Programming, Evolutionary Computation, multi-objective optimization, Pareto-optimal front, trade studies )

Fink, Wolfgang

2008-04-01

204

Interpolation of multi-sheeted multi-dimensional potential-energy surfaces via a linear optimization procedure  

NASA Astrophysics Data System (ADS)

Significant progress has been achieved in recent years with the development of high-dimensional permutationally invariant analytic Born-Oppenheimer potential-energy surfaces, making use of polynomial invariant theory. In this work, we have developed a generalization of this approach which is suitable for the construction of multi-sheeted multi-dimensional potential-energy surfaces exhibiting seams of conical intersections. The method avoids the nonlinear optimization problem which is encountered in the construction of multi-sheeted diabatic potential-energy surfaces from ab initio electronic-structure data. The key of the method is the expansion of the coefficients of the characteristic polynomial in polynomials which are invariant with respect to the point group of the molecule or the permutation group of like atoms. The multi-sheeted adiabatic potential-energy surface is obtained from the Frobenius companion matrix which contains the fitted coefficients. A three-sheeted nine-dimensional adiabatic potential-energy surface of the 2T2 electronic ground state of the methane cation has been constructed as an example of the application of this method.

Opalka, Daniel; Domcke, Wolfgang

2013-06-01

205

A family of Eulerian-Lagrangian localized adjoint methods for multi-dimensional advection-reaction equations  

SciTech Connect

Many difficult problems arise in the numerical simulation of fluid flow processes within porous media in petroleum reservoir simulation and in subsurface contaminant transport and remediation. The authors develop a family of Eulerian-Lagrangian localized adjoint methods for the solution of the initial-boundary value problems for first-order advection-reaction equations on general multi-dimensional domains. Different tracking algorithms, including the Euler and Runge-Kutta algorithms, are used. The derived schemes, which are full mass conservative, naturally incorporate inflow boundary conditions into their formulations and do not need any artificial outflow boundary conditions. Moreover, they have regularly structured, well-conditioned, symmetric, and positive-definite coefficient matrices, which can be efficiently solved by the conjugate gradient method in an optimal order number of iterations without any preconditioning needed. Numerical results are presented to compare the performance of the ELLAM schemes with many well studied and widely used methods, including the upwind finite difference method, the Galerkin and the Petrov-Galerkin finite element methods with backward-Euler or Crank-Nicolson temporal discretization, the streamline diffusion finite element methods, the monotonic upstream-centered scheme for conservation laws (MUSCL), and the Minmod scheme.

Wang, H.; Man, S. [Univ. of South Carolina, Columbia, SC (United States). Dept. of Mathematics] [Univ. of South Carolina, Columbia, SC (United States). Dept. of Mathematics; Ewing, R.E. [Texas A and M Univ., College Station, TX (United States). Inst for Scientific Computation] [Texas A and M Univ., College Station, TX (United States). Inst for Scientific Computation; Qin, G.; Lyons, S.L. [Mobil Technology Co., Dallas, TX (United States). Upstream Strategic Research Center] [Mobil Technology Co., Dallas, TX (United States). Upstream Strategic Research Center; Al-Lawatia, M. [Sultan Qaboos Univ., Muscat (Oman). Dept. of Mathematics and Statistics] [Sultan Qaboos Univ., Muscat (Oman). Dept. of Mathematics and Statistics

1999-06-10

206

Finite-volume application of high order ENO schemes to multi-dimensional boundary-value problems  

NASA Technical Reports Server (NTRS)

The finite volume approach in developing multi-dimensional, high-order accurate essentially non-oscillatory (ENO) schemes is considered. In particular, a two dimensional extension is proposed for the Euler equation of gas dynamics. This requires a spatial reconstruction operator that attains formal high order of accuracy in two dimensions by taking account of cross gradients. Given a set of cell averages in two spatial variables, polynomial interpolation of a two dimensional primitive function is employed in order to extract high-order pointwise values on cell interfaces. These points are appropriately chosen so that correspondingly high-order flux integrals are obtained through each interface by quadrature, at each point having calculated a flux contribution in an upwind fashion. The solution-in-the-small of Riemann's initial value problem (IVP) that is required for this pointwise flux computation is achieved using Roe's approximate Riemann solver. Issues to be considered in this two dimensional extension include the implementation of boundary conditions and application to general curvilinear coordinates. Results of numerical experiments are presented for qualitative and quantitative examination. These results contain the first successful application of ENO schemes to boundary value problems with solid walls.

Casper, Jay; Dorrepaal, J. Mark

1990-01-01

207

Confirmatory factor analysis of DOSPERT scale with Chinese university students.  

PubMed

The factor structure of the 30-item Domain Specific Risk Taking Attitude (DOSPERT) scale (Blais & Weber, 2006) was examined with a convenience sample of 205 Chinese undergraduate students from Macao. A comparison of five competing models via confirmatory factor analysis yielded empirical support for the perspective that risk-taking attitude was content-dependent. After removing the items in the Financial subscale of the DOSPERT scale and some post hoc modifications, a reasonably good fit to the four-correlated-factor model was achieved, in concordance with the theoretical framework. However, items in some scales needed further revision to purify their factor structure so that the DOSPERT scale would be a more psychometrically sound measure for investigating one's risk-taking attitudes in different life domains. PMID:24765720

Wu, Joseph; Cheung, Hoi Yan

2014-02-01

208

Imaging Multi-Dimensional Electrical Resistivity Structure as a Tool in Developing Enhanced Geothermal Systems (EGS)  

SciTech Connect

The overall goal of this project has been to develop desktop capability for 3-D EM inversion as a complement or alternative to existing massively parallel platforms. We have been fortunate in having a uniquely productive cooperative relationship with Kyushu University (Y. Sasaki, P.I.) who supplied a base-level 3-D inversion source code for MT data over a half-space based on staggered grid finite differences. Storage efficiency was greatly increased in this algorithm by implementing a symmetric L-U parameter step solver, and by loading the parameter step matrix one frequency at a time. Rules were established for achieving sufficient jacobian accuracy versus mesh discretization, and regularization was much improved by scaling the damping terms according to influence of parameters upon the measured response. The modified program was applied to 101 five-channel MT stations taken over the Coso East Flank area supported by the DOE and the Navy. Inversion of these data on a 2 Gb desktop PC using a half-space starting model recovered the main features of the subsurface resistivity structure seen in a massively parallel inversion which used a series of stitched 2-D inversions as a starting model. In particular, a steeply west-dipping, N-S trending conductor was resolved under the central-west portion of the East Flank. It may correspond to a highly saline magamtic fluid component, residual fluid from boiling, or less likely cryptic acid sulphate alteration, all in a steep fracture mesh. This work gained student Virginia Maris the Best Student Presentation at the 2006 GRC annual meeting.

Philip E. Wannamaker

2007-12-31

209

Sensate abstraction: hybrid strategies for multi-dimensional data in expressive virtual reality contexts  

NASA Astrophysics Data System (ADS)

ATLAS in silico is an interactive installation/virtual environment that provides an aesthetic encounter with metagenomics data (and contextual metadata) from the Global Ocean Survey (GOS). The installation creates a visceral experience of the abstraction of nature in to vast data collections - a practice that connects expeditionary science of the 19th Century with 21st Century expeditions like the GOS. Participants encounter a dream-like, highly abstract, and datadriven virtual world that combines the aesthetics of fine-lined copper engraving and grid-like layouts of 19th Century scientific representation with 21st Century digital aesthetics including wireframes and particle systems. It is resident at the Calit2 Immersive visualization Laboratory on the campus of UC San Diego, where it continues in active development. The installation utilizes a combination of infrared motion tracking, custom computer vision, multi-channel (10.1) spatialized interactive audio, 3D graphics, data sonification, audio design, networking, and the VarrierTM 60 tile, 100-million pixel barrier strip auto-stereoscopic display. Here we describe the physical and audio display systems for the installation and a hybrid strategy for multi-channel spatialized interactive audio rendering in immersive virtual reality that combines amplitude, delay and physical modeling-based, real-time spatialization approaches for enhanced expressivity in the virtual sound environment that was developed in the context of this artwork. The desire to represent a combination of qualitative and quantitative multidimensional, multi-scale data informs the artistic process and overall system design. We discuss the resulting aesthetic experience in relation to the overall system.

West, Ruth; Gossmann, Joachim; Margolis, Todd; Schulze, Jurgen P.; Lewis, J. P.; Hackbarth, Ben; Mostafavi, Iman

2009-02-01

210

Data Mining: Data Analysis on a Grand Scale? Padhraic Smyth  

E-print Network

Data Mining: Data Analysis on a Grand Scale? Padhraic Smyth Information and Computer Science for Statistical Methods in Medical Research, September 2000 1 #12;Abstract Modern data mininghas evolvedlargelyas aresult ofe orts bycomputer scientists to address the needs of data owners" in extracting useful

Smyth, Padhraic

211

Exploiting polarization using multi-frequency SAR data and multi-dimensional time-frequency techniques  

NASA Astrophysics Data System (ADS)

During recent years, Time-Frequency (TF) techniques have been introduced to characterize scene polarimetric behaviours using PolSAR data. In this paper, we apply a TF decomposition approach to the analysis of PolSAR data with different frequency bands and show some polarimetric TF behaviours of various scenes. The PolSAR data may be decomposed in azimuth direction, range direction only and in both directions. Two statistical descriptor, i.e., polarimetric TF stationarity and coherence indicators, are used to depict the features of the scene backscattering response. Their individual performance is assessed. The polarimetric TF features, extracted from the scenes of interest, can show some special relevant information compared to the original full resolution case. Moreover, with the availability of new multi-frequency full-polarization high resolution F-SAR data, the results of same site with respect to different frequency bands are exploited and compared with each other.

Hu, Canbin; Wang, Wei; Zhao, Lingjun; Kuang, Gangyao

2014-03-01

212

Multi-dimensional high order essentially non-oscillatory finite difference methods in generalized coordinates  

NASA Technical Reports Server (NTRS)

The nonlinear stability of compact schemes for shock calculations is investigated. In recent years compact schemes were used in various numerical simulations including direct numerical simulation of turbulence. However to apply them to problems containing shocks, one has to resolve the problem of spurious numerical oscillation and nonlinear instability. A framework to apply nonlinear limiting to a local mean is introduced. The resulting scheme can be proven total variation (1D) or maximum norm (multi D) stable and produces nice numerical results in the test cases. The result is summarized in the preprint entitled 'Nonlinearly Stable Compact Schemes for Shock Calculations', which was submitted to SIAM Journal on Numerical Analysis. Research was continued on issues related to two and three dimensional essentially non-oscillatory (ENO) schemes. The main research topics include: parallel implementation of ENO schemes on Connection Machines; boundary conditions; shock interaction with hydrogen bubbles, a preparation for the full combustion simulation; and direct numerical simulation of compressible sheared turbulence.

Shu, Chi-Wang

1992-01-01

213

Multi-Dimensional High Order Essentially Non-Oscillatory Finite Difference Methods in Generalized Coordinates  

NASA Technical Reports Server (NTRS)

This project is about the development of high order, non-oscillatory type schemes for computational fluid dynamics. Algorithm analysis, implementation, and applications are performed. Collaborations with NASA scientists have been carried out to ensure that the research is relevant to NASA objectives. The combination of ENO finite difference method with spectral method in two space dimension is considered, jointly with Cai [3]. The resulting scheme behaves nicely for the two dimensional test problems with or without shocks. Jointly with Cai and Gottlieb, we have also considered one-sided filters for spectral approximations to discontinuous functions [2]. We proved theoretically the existence of filters to recover spectral accuracy up to the discontinuity. We also constructed such filters for practical calculations.

Shu, Chi-Wang

1998-01-01

214

Multi-dimensional models of circumstellar shells around evolved massive stars  

NASA Astrophysics Data System (ADS)

Context. Massive stars shape their surrounding medium through the force of their stellar winds, which collide with the circumstellar medium. Because the characteristics of these stellar winds vary over the course of the evolution of the star, the circumstellar matter becomes a reflection of the stellar evolution and can be used to determine the characteristics of the progenitor star. In particular, whenever a fast wind phase follows a slow wind phase, the fast wind sweeps up its predecessor in a shell, which is observed as a circumstellar nebula. Aims: We make 2D and 3D numerical simulations of fast stellar winds sweeping up their slow predecessors to investigate whether numerical models of these shells have to be 3D, or whether 2D models are sufficient to reproduce the shells correctly. Methods: We use the MPI-AMRVAC code, using hydrodynamics with optically thin radiative losses included, to make numerical models of circumstellar shells around massive stars in 2D and 3D and compare the results. We focus on those situations where a fast Wolf-Rayet star wind sweeps up the slower wind emitted by its predecessor, being either a red supergiant or a luminous blue variable. Results: As the fast Wolf-Rayet wind expands, it creates a dense shell of swept up material that expands outward, driven by the high pressure of the shocked Wolf-Rayet wind. These shells are subject to a fair variety of hydrodynamic-radiative instabilities. If the Wolf-Rayet wind is expanding into the wind of a luminous blue variable phase, the instabilities will tend to form a fairly small-scale, regular filamentary lattice with thin filaments connecting knotty features. If the Wolf-Rayet wind is sweeping up a red supergiant wind, the instabilities will form larger interconnected structures with less regularity. The numerical resolution must be high enough to resolve the compressed, swept-up shell and the evolving instabilities, which otherwise may not even form. Conclusions: Our results show that 3D models, when translated to observed morphologies, give realistic results that can be compared directly to observations. The 3D structure of the nebula will help to distinguish different progenitor scenarios.

van Marle, A. J.; Keppens, R.

2012-11-01

215

High-resolution heteronuclear multi-dimensional NMR spectroscopy in magnetic fields with unknown spatial variations  

NASA Astrophysics Data System (ADS)

Heteronuclear NMR spectroscopy is an extremely powerful tool for determining the structures of organic molecules and is of particular significance in the structural analysis of proteins. In order to leverage the method’s potential for structural investigations, obtaining high-resolution NMR spectra is essential and this is generally accomplished by using very homogeneous magnetic fields. However, there are several situations where magnetic field distortions and thus line broadening is unavoidable, for example, the samples under investigation may be inherently heterogeneous, and the magnet’s homogeneity may be poor. This line broadening can hinder resonance assignment or even render it impossible. We put forth a new class of pulse sequences for obtaining high-resolution heteronuclear spectra in magnetic fields with unknown spatial variations based on distant dipolar field modulations. This strategy’s capabilities are demonstrated with the acquisition of high-resolution 2D gHSQC and gHMBC spectra. These sequences’ performances are evaluated on the basis of their sensitivities and acquisition efficiencies. Moreover, we show that by encoding and decoding NMR observables spatially, as is done in ultrafast NMR, an extra dimension containing J-coupling information can be obtained without increasing the time necessary to acquire a heteronuclear correlation spectrum. Since the new sequences relax magnetic field homogeneity constraints imposed upon high-resolution NMR, they may be applied in portable NMR sensors and studies of heterogeneous chemical and biological materials.

Zhang, Zhiyong; Huang, Yuqing; Smith, Pieter E. S.; Wang, Kaiyu; Cai, Shuhui; Chen, Zhong

2014-05-01

216

Instrumentation development for multi-dimensional two-phase flow modeling  

SciTech Connect

A multi-faceted instrumentation approach is described which has played a significant role in obtaining fundamental data for two-phase flow model development. This experimental work supports the development of a three-dimensional, two-fluid, four field computational analysis capability. The goal of this development is to utilize mechanistic models and fundamental understanding rather than rely on empirical correlations to describe the interactions in two-phase flows. The four fields (two dispersed and two continuous) provide a means for predicting the flow topology and the local variables over the full range of flow regimes. The fidelity of the model development can be verified by comparisons of the three-dimensional predictions with local measurements of the flow variables. Both invasive and non-invasive instrumentation techniques and their strengths and limitations are discussed. A critical aspect of this instrumentation development has been the use of a low pressure/temperature modeling fluid (R-134a) in a vertical duct which permits full optical access to visualize the flow fields in all two-phase flow regimes. The modeling fluid accurately simulates boiling steam-water systems. Particular attention is focused on the use of a gamma densitometer to obtain line-averaged and cross-sectional averaged void fractions. Hot-film anemometer probes provide data on local void fraction, interfacial frequency, bubble and droplet size, as well as information on the behavior of the liquid-vapor interface in annular flows. A laser Doppler velocimeter is used to measure the velocity of liquid-vapor interfaces in bubbly, slug and annular flows. Flow visualization techniques are also used to obtain a qualitative understanding of the two-phase flow structure, and to obtain supporting quantitative data on bubble size. Examples of data obtained with these various measurement methods are shown.

Kirouac, G.J.; Trabold, T.A.; Vassallo, P.F.; Moore, W.E.; Kumar, R. [Lockheed Martin Corp., Schenectady, NY (United States)

1999-06-01

217

Assessing multiple-group diagnostic problems with multi-dimensional receiver operating characteristic surfaces: Application to proton MR Spectroscopy (MRS) in HIV-related neurological injury  

Microsoft Academic Search

We present the multi-dimensional Receiver Operating Characteristic (ROC) surface, a plot of the true classification rates of tests based on levels of biological markers, for multi-group discrimination, as an extension of the ROC curve, commonly used in two-group diagnostic testing. The volume under this surface (VUS) is a global accuracy measure of a test to classify subjects in multiple groups

Constantin T. Yiannoutsos; Christos T. Nakas; Bradford A. Navia

2008-01-01

218

A scaling analysis of ozone photochemistry: I Model development  

NASA Astrophysics Data System (ADS)

A scaling analysis has been used to capture the integrated behaviour of several photochemical mechanisms for a wide range of precursor concentrations and a variety of environmental conditions. The Buckingham Pi method of dimensional analysis was used to express the relevant variables in terms of dimensionless groups. These grouping show maximum ozone, initial NOx and initial VOC concentrations are made non-dimensional by the average NO2 photolysis rate (jav) and the rate constant for the NO-O3 titration reaction (kNO); temperature by the NO-O3 activation energy (ENO) and Boltzmann constant (k) and total irradiation time by the cumulative jav?t photolysis rate (?3). The analysis shows dimensionless maximum ozone concentration can be described by a product of powers of dimensionless initial NOx concentration, dimensionless temperature, and a similarity curve directly dependent on the ratio of initial VOC to NOx concentration and implicitly dependent on the cumulative NO2 photolysis rate. When Weibull transformed, the similarity relationship shows a scaling break with dimensionless model output clustering onto two straight line segments, parameterized using four variables: two describing the slopes of the line segments and two giving the location of their intersection. A fifth parameter is used to normalize the model output. The scaling analysis, similarity curve and parameterization appear to be independent of the details of the chemical mechanism, hold for a variety of VOC species and mixtures and a wide range of temperatures and actinic fluxes.

Ainslie, B.; Steyn, D. G.

2005-12-01

219

The Importance of Non-Isotropic Conduction in Multi-Dimensional MHD Calculations of Coronal Magnetic Loops  

NASA Astrophysics Data System (ADS)

Much progress has recently been made in modeling and observations of coronal loops. Most recent modeling has focused on 1-D models to investigate the location of the heating responsible for the high temperatures of these loops and the corona in general. More specifically the focus has been on various forms of pulsed heating with much argument as to whether these pulses arise in the corona or the transition region. There has been very little work done using multi-dimensional models for two reasons: 1) to do this correctly one must treat thermal conduction in a non-isotropic manner, only along the magnetic field lines, and 2) to have the calculations be meaningful one must adequately resolve the transition region, to approximately 12 km resolution. We have addressed both of these problems in using the University of Chicago Flash code to model the solar atmosphere from a temperature of 8,000K to over 1,000,000K. Adequate resolution was achieved by setting the adaptive mesh parameter to a sufficiently large value that dynamic regridding gave the needed 12 km resolution. Thermal conduction was originally handled in the program as an isotropic quantity. However, we have developed new modules for the code such that conduction was calculated as occurring only along the magnetic field lines. Preliminary results show that the 2-D results with non-isotropic conduction more closely match the 1-D results than the 2-D results with isotropic conduction. This indicates that 1-D calculations are still valuable. We also find that with sufficiently detailed observations one should be able to discriminate between heating originating in the transition region and heating originating in the corona.

Poland, Arthur I.; Forjan, G.

2009-05-01

220

Methods for a longitudinal quantitative outcome with a multivariate Gaussian distribution multi-dimensionally censored by therapeutic intervention.  

PubMed

In longitudinal studies, a quantitative outcome (such as blood pressure) may be altered during follow-up by the administration of a non-randomized, non-trial intervention (such as anti-hypertensive medication) that may seriously bias the study results. Current methods mainly address this issue for cross-sectional studies. For longitudinal data, the current methods are either restricted to a specific longitudinal data structure or are valid only under special circumstances. We propose two new methods for estimation of covariate effects on the underlying (untreated) general longitudinal outcomes: a single imputation method employing a modified expectation-maximization (EM)-type algorithm and a multiple imputation (MI) method utilizing a modified Monte Carlo EM-MI algorithm. Each method can be implemented as one-step, two-step, and full-iteration algorithms. They combine the advantages of the current statistical methods while reducing their restrictive assumptions and generalizing them to realistic scenarios. The proposed methods replace intractable numerical integration of a multi-dimensionally censored MVN posterior distribution with a simplified, sufficiently accurate approximation. It is particularly attractive when outcomes reach a plateau after intervention due to various reasons. Methods are studied via simulation and applied to data from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications study of treatment for type 1 diabetes. Methods proved to be robust to high dimensions, large amounts of censored data, low within-subject correlation, and when subjects receive non-trial intervention to treat the underlying condition only (with high Y), or for treatment in the majority of subjects (with high Y) in combination with prevention for a small fraction of subjects (with normal Y). PMID:24258796

Sun, Wanjie; Larsen, Michael D; Lachin, John M

2014-04-15

221

Selective comprehensive multi-dimensional separation for resolution enhancement in high performance liquid chromatography. Part I: principles and instrumentation.  

PubMed

An approach to enhancing the resolution of select portions of conventional one-dimensional high performance liquid chromatography (HPLC) separations was developed, which we refer to as selective comprehensive two-dimensional HPLC (sLC×LC). In this first of a series of two papers we describe the principles of this approach, which breaks the long-standing link in on-line multi-dimensional chromatography between the timescales of sampling the first dimension (¹D) separation and the separation of fractions of ¹D effluent in the second dimension. This allows rapid, high-efficiency separations to be used in the first dimension, while still adequately sampling ¹D peaks. Transfer, transient storage, and subsequent second dimension (²D) separations of multiple fractions of a particular ¹D peak produces a two-dimensional chromatogram that reveals the coordinates of the peak in both dimensions of the chromatographic space. Using existing valve technology we find that the approach is repeatable (%RSD of peak area <1.5%), even at very short first dimension sampling times--as low as 1s. We have also systematically studied the critical influence of the volume and composition of fractions transferred from the first to the second dimension of the sLC × LC system with reversed-phase columns in both dimensions, and the second dimension operated isocratically. We find that dilution of the transferred fraction, so that it contains 10-20% less organic solvent than the ²D eluent, generally mitigates the devastating effects of large transfer volumes on ²D performance in this type of system. Several example applications of the sLC × LC approach are described in the second part of this two-part series. We anticipate that future advances in the valve technology used here will significantly widen the scope of possible applications of the sLC × LC approach. PMID:21802089

Groskreutz, Stephen R; Swenson, Michael M; Secor, Laura B; Stoll, Dwight R

2012-03-01

222

Exploring Signal-to-noise Ratio and Sensitivity in Non-Uniformly Sampled Multi-Dimensional NMR Spectra  

PubMed Central

It is well established that non-uniform sampling (NUS) allows acquisition of multi-dimensional NMR spectra at a resolution that cannot be obtained with traditional uniform acquisition through the indirect dimensions. However, the impact of NUS on the signal-to-noise ratio (SNR) and sensitivity are less well documented. SNR and sensitivity are essential aspects of NMR experiments as they define the quality and extent of data that can be obtained. This is particularly important for spectroscopy with low concentration samples of biological macromolecules. There are different ways of defining the SNR depending on how to measure the noise, and the distinction between SNR and sensitivity is often not clear. While there are defined procedures for measuring sensitivity with high concentration NMR standards, such as sucrose, there is no clear or generally accepted definition of sensitivity when comparing different acquisition and processing methods for spectra of biological macromolecules with many weak signals close to the level of noise. Here we propose tools for estimating the SNR and sensitivity of NUS spectra with respect to sampling schedule and reconstruction method. We compare uniformly acquired spectra with NUS spectra obtained in the same total measuring time. The time saving obtained when only 1/k of the Nyquist grid points are sampled is used to measure k-fold more scans per increment. We show that judiciously chosen NUS schedules together with suitable reconstruction methods can yield a significant increase of the SNR within the same total measurement time. Furthermore, we propose to define the sensitivity as the probability to detect weak peaks and show that time-equivalent NUS can significantly increase this detection sensitivity. The sensitivity gain increases with the number of NUS indirect dimensions. Thus, well-chosen NUS schedules and reconstruction methods can significantly increase the information content of multidimensional NMR spectra of challenging biological macromolecules. PMID:23274692

Hyberts, Sven G.; Robson, Scott A.; Wagner, Gerhard

2013-01-01

223

GAIN Working Papers: Rasch Analysis of the Substance Problem Scale  

Microsoft Academic Search

Purpose. The purpose of this report is to provide a brief psychometric analysis of the Substance Problem Scale - past year (SPSpy) using the Rasch measurement model. The SPSpy consists of 16 past-year yes\\/no items (alpha=.89) related to any alcohol or drug use disorders, including abuse, dependence, and substance induced health and psychiatric problems. Methods. Data were analyzed on 7,435

Kendon J. Conrad; Karen M. Conrad; Michael L. Dennis; Barth B. Riley

224

Empirical analysis of scaling and fractal characteristics of outpatients  

NASA Astrophysics Data System (ADS)

The paper uses power-law frequency distribution, power spectrum analysis, detrended fluctuation analysis, and surrogate data testing to evaluate outpatient registration data of two hospitals in China and to investigate the human dynamics of systems that use the “first come, first served” protocols. The research results reveal that outpatient behavior follow scaling laws. The results also suggest that the time series of inter-arrival time exhibit 1/f noise and have positive long-range correlation. Our research may contribute to operational optimization and resource allocation in hospital based on FCFS admission protocols.

Zhang, Li-Jiang; Liu, Zi-Xian; Guo, Jin-Li

2014-01-01

225

Bicoherence analysis of model-scale jet noise.  

PubMed

Bicoherence analysis has been used to characterize nonlinear effects in the propagation of noise from a model-scale, Mach-2.0, unheated jet. Nonlinear propagation effects are predominantly limited to regions near the peak directivity angle for this jet source and propagation range. The analysis also examines the practice of identifying nonlinear propagation by comparing spectra measured at two different distances and assuming far-field, linear propagation between them. This spectral comparison method can lead to erroneous conclusions regarding the role of nonlinearity when the observations are made in the geometric near field of an extended, directional radiator, such as a jet. PMID:21110528

Gee, Kent L; Atchley, Anthony A; Falco, Lauren E; Shepherd, Micah R; Ukeiley, Lawrence S; Jansen, Bernard J; Seiner, John M

2010-11-01

226

The scale analysis sequence for LWR fuel depletion  

SciTech Connect

The SCALE (Standardized Computer Analyses for Licensing Evaluation) code system is used extensively to perform away-from-reactor safety analysis (particularly criticality safety, shielding, heat transfer analyses) for spent light water reactor (LWR) fuel. Spent fuel characteristics such as radiation sources, heat generation sources, and isotopic concentrations can be computed within SCALE using the SAS2 control module. A significantly enhanced version of the SAS2 control module, which is denoted as SAS2H, has been made available with the release of SCALE-4. For each time-dependent fuel composition, SAS2H performs one-dimensional (1-D) neutron transport analyses (via XSDRNPM-S) of the reactor fuel assembly using a two-part procedure with two separate unit-cell-lattice models. The cross sections derived from a transport analysis at each time step are used in a point-depletion computation (via ORIGEN-S) that produces the burnup-dependent fuel composition to be used in the next spectral calculation. A final ORIGEN-S case is used to perform the complete depletion/decay analysis using the burnup-dependent cross sections. The techniques used by SAS2H and two recent applications of the code are reviewed in this paper. 17 refs., 5 figs., 5 tabs.

Hermann, O.W.; Parks, C.V.

1991-01-01

227

Scaling analysis for the investigation of slip mechanisms in nanofluids  

NASA Astrophysics Data System (ADS)

The primary objective of this study is to investigate the effect of slip mechanisms in nanofluids through scaling analysis. The role of nanoparticle slip mechanisms in both water- and ethylene glycol-based nanofluids is analyzed by considering shape, size, concentration, and temperature of the nanoparticles. From the scaling analysis, it is found that all of the slip mechanisms are dominant in particles of cylindrical shape as compared to that of spherical and sheet particles. The magnitudes of slip mechanisms are found to be higher for particles of size between 10 and 80 nm. The Brownian force is found to dominate in smaller particles below 10 nm and also at smaller volume fraction. However, the drag force is found to dominate in smaller particles below 10 nm and at higher volume fraction. The effect of thermophoresis and Magnus forces is found to increase with the particle size and concentration. In terms of time scales, the Brownian and gravity forces act considerably over a longer duration than the other forces. For copper-water-based nanofluid, the effective contribution of slip mechanisms leads to a heat transfer augmentation which is approximately 36% over that of the base fluid. The drag and gravity forces tend to reduce the Nusselt number of the nanofluid while the other forces tend to enhance it.

Savithiri, S.; Pattamatta, Arvind; Das, Sarit K.

2011-07-01

228

Microencapsulation reactor scale-up by dimensional analysis.  

PubMed

A microencapsulation process for preparing protein-loaded microspheres based on a solvent-extraction method was scaled up using continuously stirred tank reactors (CSTR) from 1 L to 100 L in batch size. This study was concerned with developing a quantitative correlation between the size of the microspheres and process parameters. The process parameters considered include operational variables and physical properties associated with both the dispersion and dispersed phases. Dimensional analysis was used to establish such a correlation based on protein-free poly(lactic acid-co-glycolic acid) microspheres in an oil-in-water emulsion system prepared in a 1 L CSTR. This correlation was found to accurately describe the preparation of protein-loaded microspheres in a solid-in-oil-in-water system. Poly(methyl methacrylate) was found to behave similarly to poly(lactic-acid-co-glycolic acid) and could be used as a model polymer for scale-up investigation. This study showed that dimensional analysis can be used to predictably scale the current microencapsulation process up to 100 L to produce particles of defined size. PMID:8903785

Maa, Y F; Hsu, C

1996-01-01

229

Scaling analysis for the investigation of slip mechanisms in nanofluids  

PubMed Central

The primary objective of this study is to investigate the effect of slip mechanisms in nanofluids through scaling analysis. The role of nanoparticle slip mechanisms in both water- and ethylene glycol-based nanofluids is analyzed by considering shape, size, concentration, and temperature of the nanoparticles. From the scaling analysis, it is found that all of the slip mechanisms are dominant in particles of cylindrical shape as compared to that of spherical and sheet particles. The magnitudes of slip mechanisms are found to be higher for particles of size between 10 and 80 nm. The Brownian force is found to dominate in smaller particles below 10 nm and also at smaller volume fraction. However, the drag force is found to dominate in smaller particles below 10 nm and at higher volume fraction. The effect of thermophoresis and Magnus forces is found to increase with the particle size and concentration. In terms of time scales, the Brownian and gravity forces act considerably over a longer duration than the other forces. For copper-water-based nanofluid, the effective contribution of slip mechanisms leads to a heat transfer augmentation which is approximately 36% over that of the base fluid. The drag and gravity forces tend to reduce the Nusselt number of the nanofluid while the other forces tend to enhance it. PMID:21791036

2011-01-01

230

SCALE 6: Comprehensive Nuclear Safety Analysis Code System  

SciTech Connect

Version 6 of the Standardized Computer Analyses for Licensing Evaluation (SCALE) computer software system developed at Oak Ridge National Laboratory, released in February 2009, contains significant new capabilities and data for nuclear safety analysis and marks an important update for this software package, which is used worldwide. This paper highlights the capabilities of the SCALE system, including continuous-energy flux calculations for processing multigroup problem-dependent cross sections, ENDF/B-VII continuous-energy and multigroup nuclear cross-section data, continuous-energy Monte Carlo criticality safety calculations, Monte Carlo radiation shielding analyses with automated three-dimensional variance reduction techniques, one- and three-dimensional sensitivity and uncertainty analyses for criticality safety evaluations, two- and three-dimensional lattice physics depletion analyses, fast and accurate source terms and decay heat calculations, automated burnup credit analyses with loading curve search, and integrated three-dimensional criticality accident alarm system analyses using coupled Monte Carlo criticality and shielding calculations.

Bowman, Stephen M [ORNL

2011-01-01

231

Wood transverse fracture analysis at the mesoscopic scale  

NASA Astrophysics Data System (ADS)

The present study is an analysis of wood fracture behavior at the mesoscopic scale (i.e. the scale of growth ring). Radial TR crack growth mechanisms are complex and involve several events such as secondary cracks creation while cracks extend from one growth ring to another. Crack tip strain field of radial TR crack is measured by digital image correlation in order to better understand these phenomena. A numerical model for wood fracture has been conducted and a transverse model of spruce wood has been implemented. The simulation is realized by Material Point Method, a meshless method that discretizes material bodies into a collection of material points or particles. This promising tool improves the understanding of transverse fracture in spruce wood and can easily be used in further studies.

Bigorgne, L.; Brunet, M.; Maigre, H.

2010-06-01

232

Reactor Physics Methods and Analysis Capabilities in SCALE  

SciTech Connect

The TRITON sequence of the SCALE code system provides a powerful, robust, and rigorous approach for performing reactor physics analysis. This paper presents a detailed description of TRITON in terms of its key components used in reactor calculations. The ability to accurately predict the nuclide composition of depleted reactor fuel is important in a wide variety of applications. These applications include, but are not limited to, the design, licensing, and operation of commercial/research reactors and spent-fuel transport/storage systems. New complex design projects such as next-generation power reactors and space reactors require new high-fidelity physics methods, such as those available in SCALE/TRITON, that accurately represent the physics associated with both evolutionary and revolutionary reactor concepts as they depart from traditional and well-understood light water reactor designs.

DeHart, Mark D [ORNL; Bowman, Stephen M [ORNL

2011-01-01

233

Scaling and dimensional analysis of acoustic streaming jets  

NASA Astrophysics Data System (ADS)

This paper focuses on acoustic streaming free jets. This is to say that progressive acoustic waves are used to generate a steady flow far from any wall. The derivation of the governing equations under the form of a nonlinear hydrodynamics problem coupled with an acoustic propagation problem is made on the basis of a time scale discrimination approach. This approach is preferred to the usually invoked amplitude perturbations expansion since it is consistent with experimental observations of acoustic streaming flows featuring hydrodynamic nonlinearities and turbulence. Experimental results obtained with a plane transducer in water are also presented together with a review of the former experimental investigations using similar configurations. A comparison of the shape of the acoustic field with the shape of the velocity field shows that diffraction is a key ingredient in the problem though it is rarely accounted for in the literature. A scaling analysis is made and leads to two scaling laws for the typical velocity level in acoustic streaming free jets; these are both observed in our setup and in former studies by other teams. We also perform a dimensional analysis of this problem: a set of seven dimensionless groups is required to describe a typical acoustic experiment. We find that a full similarity is usually not possible between two acoustic streaming experiments featuring different fluids. We then choose to relax the similarity with respect to sound attenuation and to focus on the case of a scaled water experiment representing an acoustic streaming application in liquid metals, in particular, in liquid silicon and in liquid sodium. We show that small acoustic powers can yield relatively high Reynolds numbers and velocity levels; this could be a virtue for heat and mass transfer applications, but a drawback for ultrasonic velocimetry.

Moudjed, B.; Botton, V.; Henry, D.; Ben Hadid, H.; Garandet, J.-P.

2014-09-01

234

Multi-Dimensional Error Analysis of Nearshore Wave Modeling Tools, with Application Toward Data-Driven Boundary Correction  

E-print Network

As the forecasting models become more sophisticated in their physics and possible depictions of the nearshore hydrodynamics, they also become increasingly sensitive to errors in the inputs. These input errors include: mis-specification of the input...

Jiang, Boyang

2012-02-14

235

Phase retrieval for improved multi-dimensional velocimetric analysis of X-ray blood flow speckle patterns  

Microsoft Academic Search

Threedimensional flow measurements, obtained from high? resolution synchrotronbased xray phase contrast i mages of blood invitro , are presented. Using data collected on beamline BL20XU at the SPring?8 synchrotron in Hyogo, Japan, we demonstrate the benefits to be gained by preproces sing of speckled Xray phase contrast images prior to PIV a nalysis. Such preprocessing techniques include use of a

S. C. Irvine; D. M. Paganin; S. Dubsky; R. A. Lewis; A. Fouras

236

Specifying and Testing a Multi-Dimensional Model of Publicness: An Analysis of Mental Health and Substance Abuse Treatment Facilities  

E-print Network

, 1987), as well as its level of: social equity; engagement with external enterprises that compel "morally governed behavior" (e.g., accreditation agencies); and openness. Data on public and private (for-profit and non-profit) mental health and substance...

Merritt, Cullen

2014-05-31

237

Dimensional analysis of small-scale steam explosion experiments  

SciTech Connect

Dimensional analysis applied to Nelson's small-scale steam explosion experiments to determine the qualitative effect of each relevant parameter for triggering a steam explosion. According to experimental results, the liquid entrapment model seems to be a consistent explanation for the steam explosion triggering mechanism. The three-dimensional oscillatory wave motion of the vapor/liquid interface is analyzed to determine the necessary conditions for local condensation and production of a coolant microjet to be entrapped in fuel. It is proposed that different contact modes between fuel and coolant may involve different initiation mechanisms of steam explosions.

Huh, K.; Corradini, M.L.

1986-05-01

238

Quantifying perception of nonlinear elastic tissue models using multidimensional scaling  

Microsoft Academic Search

Simplified soft tissue models used in surgical simulations cannot perfectly reproduce all material behaviors. In particular, many tissues exhibit the Poynting effect, which results in normal forces during shearing of tissue and is only observed in nonlinear elastic material models. In order to investigate and quantify the role of the Poynting effect on material discrimination, we performed a multi-dimensional scaling

Sarthak Misra; Philipp Fuernstahl; K. T. Ramesh; Allison M. Okamura; Matthias Harders

2009-01-01

239

Understanding large scale HPC systems through scalable monitoring and analysis.  

SciTech Connect

As HPC systems grow in size and complexity, diagnosing problems and understanding system behavior, including failure modes, becomes increasingly difficult and time consuming. At Sandia National Laboratories we have developed a tool, OVIS, to facilitate large scale HPC system understanding. OVIS incorporates an intuitive graphical user interface, an extensive and extendable data analysis suite, and a 3-D visualization engine that allows visual inspection of both raw and derived data on a geometrically correct representation of a HPC system. This talk will cover system instrumentation, data collection (including log files and the complications of meaningful parsing), analysis, visualization of both raw and derived information, and how data can be combined to increase system understanding and efficiency.

Mayo, Jackson R.; Chen, Frank Xiaoxiao; Pebay, Philippe Pierre; Wong, Matthew H.; Thompson, David; Gentile, Ann C.; Roe, Diana C.; De Sapio, Vincent; Brandt, James M.

2010-09-01

240

A Multi-scale Approach to Urban Thermal Analysis  

NASA Technical Reports Server (NTRS)

An environmental consequence of urbanization is the urban heat island effect, a situation where urban areas are warmer than surrounding rural areas. The urban heat island phenomenon results from the replacement of natural landscapes with impervious surfaces such as concrete and asphalt and is linked to adverse economic and environmental impacts. In order to better understand the urban microclimate, a greater understanding of the urban thermal pattern (UTP), including an analysis of the thermal properties of individual land covers, is needed. This study examines the UTP by means of thermal land cover response for the Salt Lake City, Utah, study area at two scales: 1) the community level, and 2) the regional or valleywide level. Airborne ATLAS (Advanced Thermal Land Applications Sensor) data, a high spatial resolution (10-meter) dataset appropriate for an environment containing a concentration of diverse land covers, are used for both land cover and thermal analysis at the community level. The ATLAS data consist of 15 channels covering the visible, near-IR, mid-IR and thermal-IR wavelengths. At the regional level Landsat TM data are used for land cover analysis while the ATLAS channel 13 data are used for the thermal analysis. Results show that a heat island is evident at both the community and the valleywide level where there is an abundance of impervious surfaces. ATLAS data perform well in community level studies in terms of land cover and thermal exchanges, but other, more coarse-resolution data sets are more appropriate for large-area thermal studies. Thermal response per land cover is consistent at both levels, which suggests potential for urban climate modeling at multiple scales.

Gluch, Renne; Quattrochi, Dale A.

2005-01-01

241

Investigation of Biogrout processes by numerical analysis at pore scale  

NASA Astrophysics Data System (ADS)

Biogrout is a soil improving process that aims to improve the strength of sandy soils. The process is based on microbially induced calcite precipitation (MICP). In this study the main process is based on denitrification facilitated by bacteria indigenous to the soil using substrates, which can be derived from pretreated waste streams containing calcium salts of fatty acids and calcium nitrate, making it a cost effective and environmentally friendly process. The goal of this research is to improve the understanding of the process by numerical analysis so that it may be improved and applied properly for varying applications, such as borehole stabilization, liquefaction prevention, levee fortification and mitigation of beach erosion. During the denitrification process there are many phases present in the pore space including a liquid phase containing solutes, crystals, bacteria forming biofilms and gas bubbles. Due to the amount of phases and their dynamic changes (multiphase flow with (non-linear) reactive transport), there are many interactions making the process very complex. To understand this complexity in the system, the interactions between these phases are studied in a reductionist approach, increasing the complexity of the system by one phase at a time. The model will initially include flow, solute transport, crystal nucleation and growth in 2D at pore scale. The flow will be described by Navier-Stokes equations. Initial study and simulations has revealed that describing crystal growth for this application on a fixed grid can introduce significant fundamental errors. Therefore a level set method will be employed to better describe the interface of developing crystals in between sand grains. Afterwards the model will be expanded to 3D to provide more realistic flow, nucleation and clogging behaviour at pore scale. Next biofilms and lastly gas bubbles may be added to the model. From the results of these pore scale models the behaviour of the system may be studied and eventually observations may be extrapolated to a larger continuum scale.

Bergwerff, Luke; van Paassen, Leon A.; Picioreanu, Cristian; van Loosdrecht, Mark C. M.

2013-04-01

242

Large-scale analysis of microRNA evolution  

PubMed Central

Background In animals, microRNAs (miRNA) are important genetic regulators. Animal miRNAs appear to have expanded in conjunction with an escalation in complexity during early bilaterian evolution. Their small size and high-degree of similarity makes them challenging for phylogenetic approaches. Furthermore, genomic locations encoding miRNAs are not clearly defined in many species. A number of studies have looked at the evolution of individual miRNA families. However, we currently lack resources for large-scale analysis of miRNA evolution. Results We addressed some of these issues in order to analyse the evolution of miRNAs. We perform syntenic and phylogenetic analysis for miRNAs from 80 animal species. We present synteny maps, phylogenies and functional data for miRNAs across these species. These data represent the basis of our analyses and also act as a resource for the community. Conclusions We use these data to explore the distribution of miRNAs across phylogenetic space, characterise their birth and death, and examine functional relationships between miRNAs and other genes. These data confirm a number of previously reported findings on a larger scale and also offer novel insights into the evolution of the miRNA repertoire in animals, and it’s genomic organization. PMID:22672736

2012-01-01

243

A multi-dimensional high performance liquid chromatographic method for fingerprinting polycyclic aromatic hydrocarbons and their alkyl-homologs in the heavy gas oil fraction of Alaskan North Slope crude.  

PubMed

We report an offline multi-dimensional high performance liquid chromatography (HPLC) technique for the group separation and analysis of PAHs in a heavy gas oil fraction (boiling range 287-481 degrees C). Waxes present in the heavy gas oil fraction were precipitated using cold acetone at -20 degrees C. Recovery studies showed that the extract contained 93% (+/-1%; n=3) of the PAHs that were originally present while the wax residue contained only 6% (+/-0.5%; n=3). PAHs present in the extract were fractionated, based on number of rings, into five fractions using a semi-preparative silica column (normal-phase HPLC). These fractions were analyzed using reverse-phase HPLC (RP-HPLC) coupled to a diode array detector (DAD). The method separated alkyl and un-substituted PAHs on two reverse-phase columns in series using an acetonitrile/water mobile phase. UV spectra of the chromatographic peaks were used to differentiate among PAH groups. Further characterization of PAHs within a given group to determine the substituent alkyl carbon number used retention time matching with a suite of alkyl-PAH standards. Naphthalene, dibenzothiophene, phenanthrene and fluorene and their C1-C4 alkyl isomers were quantified. The concentrations of these compounds obtained using the current method were compared with that of a GC-MS analysis obtained from an independent oil chemistry laboratory. PMID:17482627

Saravanabhavan, Gurusankar; Helferty, Anjali; Hodson, Peter V; Brown, R Stephen

2007-07-13

244

Multi-scale analysis and simulation of powder blending in pharmaceutical manufacturing  

E-print Network

A Multi-Scale Analysis methodology was developed and carried out for gaining fundamental understanding of the pharmaceutical powder blending process. Through experiment, analysis and computer simulations, microscopic ...

Ngai, Samuel S. H

2005-01-01

245

Surface Roughness from Point Clouds - A Multi-Scale Analysis  

NASA Astrophysics Data System (ADS)

Roughness is a physical parameter of surfaces which should include the surface complexity in geophysical models. In hydrodynamic modeling, e.g., roughness should estimate the resistance caused by the surface on the flow, or in remote sensing, how the signal is scattered. Roughness needs to be estimated as a parameter of the model. This has been identified as main source of the uncertainties in model prediction, mainly due to the errors that follow a traditional roughness estimation, e.g. from surface profiles, or by a visual interpretation and manual delineation from aerial photos. Currently, roughness estimation is shifting towards point clouds of surfaces, which primarily come from laser scanning and image matching techniques. However, those data sets are also not free of errors and may affect roughness estimation. Our study focusses on the estimation of roughness indices from different point clouds, and the uncertainties that follow such a procedure. The analysis is performed on a graveled surface of a river bed in Eastern Austria, using point clouds acquired by a triangulating laser scanner (Minolta Vivid 910), photogrammetry (DSLR camera), and terrestrial laser scanner (Riegl FWF scanner). To enable their comparison, all the point clouds are transformed to a superior coordinate system. Then, different roughness indices are calculated and compared at different scales, including stochastic and features-based indices like RMS of elevation, std.dev., Peak to Valley height, openness. The analysis is additionally supported with the spectral signatures (frequency domain) of the different point clouds. The selected techniques provide point clouds of different resolution (0.1-10cm) and coverage (0.3-10m), which also justifies the multi-scale roughness analysis. By doing this, it becomes possible to differentiate between the measurement errors and the roughness of the object at the resolutions of the point clouds. Parts of this study have been funded by the project NEWFOR in the framework of European Territorial Cooperation Alpine Space.

Milenkovi?, Milutin; Ressl, Camillo; Hollaus, Markus; Pfeifer, Norbert

2013-04-01

246

Multi-dimensional Upwind Fluctuation Splitting Scheme with Mesh Adaption for Hypersonic Viscous Flow. Degree awarded by Virginia Polytechnic Inst. and State Univ., 9 Nov. 2001  

NASA Technical Reports Server (NTRS)

A multi-dimensional upwind fluctuation splitting scheme is developed and implemented for two-dimensional and axisymmetric formulations of the Navier-Stokes equations on unstructured meshes. Key features of the scheme are the compact stencil, full upwinding, and non-linear discretization which allow for second-order accuracy with enforced positivity. Throughout, the fluctuation splitting scheme is compared to a current state-of-the-art finite volume approach, a second-order, dual mesh upwind flux difference splitting scheme (DMFDSFV), and is shown to produce more accurate results using fewer computer resources for a wide range of test cases. A Blasius flat plate viscous validation case reveals a more accurate upsilon-velocity profile for fluctuation splitting, and the reduced artificial dissipation production is shown relative to DMFDSFV. Remarkably, the fluctuation splitting scheme shows grid converged skin friction coefficients with only five points in the boundary layer for this case. The second half of the report develops a local, compact, anisotropic unstructured mesh adaptation scheme in conjunction with the multi-dimensional upwind solver, exhibiting a characteristic alignment behavior for scalar problems. The adaptation strategy is extended to the two-dimensional and axisymmetric Navier-Stokes equations of motion through the concept of fluctuation minimization.

Wood, William A., III

2002-01-01

247

Measuring the multi-dimensional knowledge deprivation of HIV/AIDS: a new approach with Indian evidence on its magnitude and determinants.  

PubMed

Though HIV/AIDS poses serious risks to economic security, there is very little economics literature quantifying awareness and knowledge of this disease and their principal socioeconomic determinants. This is what the present study attempts to do in the context of India, which faces a significant threat from HIV/AIDS. The study is based on India's National Family Health Surveys covering the period of economic reforms and beyond. The contribution is both methodological and empirical. The study shows that the recent multi-dimensional deprivation approach to poverty can also be used to measure and analyse awareness and lack of knowledge of HIV/AIDS. The use of decomposable multi-dimensional measures helps in identifying regions, socioeconomic groups and aspects of HIV knowledge that should be targeted in policy interventions. The study identifies the importance of safe sex practices as an area that needs to be targeted in future information campaigns. The study also explores the impact of increased female autonomy in health and economic decision-making on their and their partners' knowledge of the disease, along with a host of other economic and demographic determinants. PMID:21756415

Ray, Ranjan; Sinha, Kompal

2011-11-01

248

Numerical analysis of field-scale transport of bromacil  

NASA Astrophysics Data System (ADS)

Field-scale transport of bromacil (5-bromo-3- sec-butyl-6-methyluracil) was analyzed using two different model processes for local description of the transport. The first was the classical, one-region convection dispersion equation (CDE) model while the second was the two-region, mobile-immobile (MIM) model. The analyses were performed by means of detailed three-dimensional, numerical simulations of the flow and the transport [Russo, D., Zaidel, J. and Laufer, A., Numerical analysis of flow and transport in a three-dimensional partially saturated heterogeneous soil. Water Resour. Res., 1998, in press], employing local soil hydraulic properties parameters from field measurements and local adsorption/desorption coefficients and the first-order degradation rate coefficient from laboratory measurements. Results of the analyses suggest that for a given flow regime, mass exchange between the mobile and the immobile regions retards the bromacil degradation, considerably affects the distribution of the bromacil resident concentration, c, at relatively large travel times, slightly affects the spatial moments of the distribution of c, and increases the skewing of the bromacil breakthrough and the uncertainty in its prediction, compared with the case in which the soil contained only a single (mobile) region. Mean and standard deviation of the simulated concentration profiles at various elapsed times were compared with measurements from a field-scale transport experiment [Tauber-Yasur, I., Hadas, A., Russo, D. and Yaron, B., Leaching of terbuthylazine and bromacil through field soils. Water, Air Soil Poln., 1998, in press] conducted at the Bet Dagan site. Given the limitations of the present study (e.g. the lack of detailed field data on the spatial variability of the soil chemical properties) the main conclusion of the present study is that the field-scale transport of bromacil at the Bet Dagan site is better quantified with the MIM model than the CDE model.

Russo, David; Tauber-Yasur, Inbar; Laufer, Asher; Yaron, Bruno

249

Parallel Index and Query for Large Scale Data Analysis  

SciTech Connect

Modern scientific datasets present numerous data management and analysis challenges. State-of-the-art index and query technologies are critical for facilitating interactive exploration of large datasets, but numerous challenges remain in terms of designing a system for process- ing general scientific datasets. The system needs to be able to run on distributed multi-core platforms, efficiently utilize underlying I/O infrastructure, and scale to massive datasets. We present FastQuery, a novel software framework that address these challenges. FastQuery utilizes a state-of-the-art index and query technology (FastBit) and is designed to process mas- sive datasets on modern supercomputing platforms. We apply FastQuery to processing of a massive 50TB dataset generated by a large scale accelerator modeling code. We demonstrate the scalability of the tool to 11,520 cores. Motivated by the scientific need to search for inter- esting particles in this dataset, we use our framework to reduce search time from hours to tens of seconds.

Chou, Jerry; Wu, Kesheng; Ruebel, Oliver; Howison, Mark; Qiang, Ji; Prabhat,; Austin, Brian; Bethel, E. Wes; Ryne, Rob D.; Shoshani, Arie

2011-07-18

250

Characterization of P2P IPTV Traffic: Scaling Analysis  

E-print Network

P2P IPTV applications arise on the Internet and will be massively used in the future. It is expected that P2P IPTV will contribute to increase the overall Internet traffic. In this context, it is important to measure the impact of P2P IPTV on the networks and to characterize this traffic. During the 2006 FIFA World Cup, we performed an extensive measurement campaign. We measured network traffic generated by broadcasting soccer games by the most popular P2P IPTV applications, namely PPLive, PPStream, SOPCast and TVAnts. From the collected data, we characterized the P2P IPTV traffic structure at different time scales. To the best of our knowledge, this is the first work, which presents a complete multiscale analysis of the P2P IPTV traffic. Our observations show that the network traffic has not the same scale behavior whether the applications use TCP or UDP. For all the applications, the download traffic is different from the upload traffic and the signaling traffic has an impact on the download traffic.

Silverston, Thomas; Salamatian, Kave

2007-01-01

251

Large-scale Biomedical Image Analysis in Grid Environments  

PubMed Central

Digital microscopy scanners are capable of capturing multi-Gigapixel images from single slides, thus producing images of sizes up to several tens of Gigabytes each, and a research study may have hundreds of slides from a specimen. The sheer size of the images and the complexity of image processing operations create roadblocks to effective integration of large-scale imaging data in research. This paper presents the application of a component-based Grid middleware system for processing extremely large images obtained from digital microscopy devices. We have developed parallel, out-of-core techniques for different classes of data processing operations commonly employed on images from confocal microscopy scanners. These techniques are combined into data pre-processing and analysis pipelines using the component-based middleware system. The experimental results show that 1) our implementation achieves good performance and can handle very large (terabyte-scale) datasets on high-performance Grid nodes, consisting of computation and/or storage clusters, and 2) it can take advantage of multiple Grid nodes connected over high-bandwidth wide-area networks by combining task- and data-parallelism. PMID:18348945

Kumar, Vijay S.; Rutt, Benjamin; Kurc, Tahsin; Catalyurek, Umit; Pan, Tony; Saltz, Joel; Chow, Sunny; Lamont, Stephan; Martone, Maryann

2012-01-01

252

Multidimensional scaling analysis of the dynamics of a country economy.  

PubMed

This paper analyzes the Portuguese short-run business cycles over the last 150 years and presents the multidimensional scaling (MDS) for visualizing the results. The analytical and numerical assessment of this long-run perspective reveals periods with close connections between the macroeconomic variables related to government accounts equilibrium, balance of payments equilibrium, and economic growth. The MDS method is adopted for a quantitative statistical analysis. In this way, similarity clusters of several historical periods emerge in the MDS maps, namely, in identifying similarities and dissimilarities that identify periods of prosperity and crises, growth, and stagnation. Such features are major aspects of collective national achievement, to which can be associated the impact of international problems such as the World Wars, the Great Depression, or the current global financial crisis, as well as national events in the context of broad political blueprints for the Portuguese society in the rising globalization process. PMID:24294132

Tenreiro Machado, J A; Mata, Maria Eugénia

2013-01-01

253

Multidimensional Scaling Analysis of the Dynamics of a Country Economy  

PubMed Central

This paper analyzes the Portuguese short-run business cycles over the last 150 years and presents the multidimensional scaling (MDS) for visualizing the results. The analytical and numerical assessment of this long-run perspective reveals periods with close connections between the macroeconomic variables related to government accounts equilibrium, balance of payments equilibrium, and economic growth. The MDS method is adopted for a quantitative statistical analysis. In this way, similarity clusters of several historical periods emerge in the MDS maps, namely, in identifying similarities and dissimilarities that identify periods of prosperity and crises, growth, and stagnation. Such features are major aspects of collective national achievement, to which can be associated the impact of international problems such as the World Wars, the Great Depression, or the current global financial crisis, as well as national events in the context of broad political blueprints for the Portuguese society in the rising globalization process. PMID:24294132

Mata, Maria Eugenia

2013-01-01

254

Metal Analysis of Scales Taken from Arctic Grayling  

Microsoft Academic Search

This study examined concentrations of metals in fish scales taken from Arctic grayling using laser ablation-induc- tively coupled plasma mass spectrometry (LA-ICPMS). The purpose was to assess whether scale metal concentrations re- flected whole muscle metal concentrations and whether the spatial distribution of metals within an individual scale varied among the growth annuli of the scales. Ten elements (Mg, Ca,

A. P. Farrell; A. H. Hodaly; S. Wang

255

Multidimensional Residual Analysis of Point Process Models for Earthquake Occurrences  

Microsoft Academic Search

Abstract Residual analysis methods for examining the fit of multi-dimensional point process models are applied to point process models for the space-time-magnitude distribution of earthquake oc- currences, using in particular the multi-dimensional version of Ogata’s epidemic-type aftershock sequence (ETAS) model and a 30-year catalog of 580 earthquakes occurring in Bear Valley, California. One method involves rescaled residuals, obtained by transforming

Frederic Paik Schoenberg

2003-01-01

256

Spatial data analysis for exploration of regional scale geothermal resources  

NASA Astrophysics Data System (ADS)

Defining a comprehensive conceptual model of the resources sought is one of the most important steps in geothermal potential mapping. In this study, Fry analysis as a spatial distribution method and 5% well existence, distance distribution, weights of evidence (WofE), and evidential belief function (EBFs) methods as spatial association methods were applied comparatively to known geothermal occurrences, and to publicly-available regional-scale geoscience data in Akita and Iwate provinces within the Tohoku volcanic arc, in northern Japan. Fry analysis and rose diagrams revealed similar directional patterns of geothermal wells and volcanoes, NNW-, NNE-, NE-trending faults, hotsprings and fumaroles. Among the spatial association methods, WofE defined a conceptual model correspondent with the real world situations, approved with the aid of expert opinion. The results of the spatial association analyses quantitatively indicated that the known geothermal occurrences are strongly spatially-associated with geological features such as volcanoes, craters, NNW-, NNE-, NE-direction faults and geochemical features such as hotsprings, hydrothermal alteration zones and fumaroles. Geophysical data contains temperature gradients over 100 °C/km and heat flow over 100 mW/m2. In general, geochemical and geophysical data were better evidence layers than geological data for exploring geothermal resources. The spatial analyses of the case study area suggested that quantitative knowledge from hydrothermal geothermal resources was significantly useful for further exploration and for geothermal potential mapping in the case study region. The results can also be extended to the regions with nearly similar characteristics.

Moghaddam, Majid Kiavarz; Noorollahi, Younes; Samadzadegan, Farhad; Sharifi, Mohammad Ali; Itoi, Ryuichi

2013-10-01

257

SWS 5182: Earth System Analysis Catalogue Description: Analysis of global-scale interdependences between climate, biogeochemical  

E-print Network

fuel 11 Terrestrial biogeochemistry Chapter 5 and Chapter 6 Account for land carbon cycle in your Earth System feedback analysis Friedlingstein et al., 2006 Projection of carbon dioxide levels a how climate, the carbon cycle, and nutrient dynamics interact in shaping global scale temperature

Ma, Lena

258

An Analysis and Synthesis of Multiple Correspondence Analysis, Optimal Scaling, Dual Scaling, Homogeneity Analysis and Other Methods for Quantifying Categorical Multivariate Data.  

ERIC Educational Resources Information Center

Several methods for quantifying categorical multivariate data (including multiple correspondence analysis and optimal scaling) are discussed and shown to be equivalent. The method can be applied by variable matrix with categorical variables, by item matrix of multiple-choice data, or by a multi-way contingency table. (NSF)

Tenenhaus, Michel; Young, Forrest W.

1985-01-01

259

Nonlinear dynamical analysis of ground level ozone concentrations at different temporal scales  

Microsoft Academic Search

The nonlinear dynamical analysis of ground level ozone concentration is carried out by using correlation integral method to examine its scale invariance property. The dynamics of the time series is often studied at one temporal scale. It is assumed that if the time series is determined to be chaotic at one temporal scale, its behavior at another scale can be

Asha B. Chelani

2010-01-01

260

Observation and Analysis of Small-Scale Solar Magnetic Structure  

NASA Astrophysics Data System (ADS)

Properties of small-scale magnetic structures in the photosphere are analyzed in multi-spectral time-series image sets obtained at the 50 cm Swedish Solar Vacuum Telescope (SVST) on the island of La Palma, Spain. Several of the images are among the highest resolution images of the solar photosphere yet obtained. Sub-arcsecond-scale magnetic 'elements' are identified, segmented, and tracked using bright points found in very high spatial resolution G-band 4305 A filtergrams. Simultaneous images including Ca II K-line filtergrams, Fe I 6302 A magnetograms, and 4686 A broadband continuum filtergrams allow cross-wavelength comparison of properties. Angular resolution of the filtergrams is typically 0.25 '' and temporal resolution is in the range of 20-100 sec; magnetogram resolution approaches 0.3'' in some images and is generally below 0.5''. To above an 84% statistical confidence level, G-band bright points occur exclusively at sites of kilogauss, sub-arcsecond, magnetic flux concentrations in the photosphere; magnetic flux concentration is a necessary but not sufficient condition for the occurrence of G-band bright points. The measured distribution of magnetic element diameters in active region network is log-normal with a modal value of 220 km (0.3''). The smallest elements observed are 120 km (0.17'') in diameter; the largest are about 600 km (0.7'') in diameter. The average contrast with respect to quiet Sun of magnetic elements in the G-band is 30%: 2-3 times higher than the average continuum contrast. Magnetic element contrast does not vary with size within the size range of G-band bright point measurements. Average contrast increases with limbward heliocentric angle to a peak of about 80% at ? = /cos? = 0.3; there is evidence of a decrease with further increase in angle. Magnetic elements undergo a continual fragmentation/merging evolution driven by the granular convective flowfield of the photosphere; morphological time scales are on the order of 100 seconds. Velocities of individual elements range from 1-5 km s-1 with an RMS value of 2.4 km s-1. The range of motion is typically on granular and mesogranular scales (1000-2500 km) with an average value of 2100 km. Individual fragments from clusters have a characteristic lifetime on the order of the granulation correlation time (6-8 minutes). The lifetime of clusters associated with persistent sinks in the granular flowfield is on the order of hours. Classical statistical analysis of displacement versus time yields a diffusion coefficient for network magnetic elements of 224.8± 0.2 km s-1. In general, the results are inconsistent with the idea of small-scale magnetic flux in the photosphere being contained in stable, isolated, 'flux tubes' and emphasize the need for better understanding of the formation and the thermal (and? non-thermal) heating of magnetic regions in the photosphere.

Berger, Thomas Edward

1997-05-01

261

Confirmatory Factor Analysis of the Educators' Attitudes toward Educational Research Scale  

ERIC Educational Resources Information Center

This article reports results of a confirmatory factor analysis performed to cross-validate the factor structure of the Educators' Attitudes Toward Educational Research Scale. The original scale had been developed by the author and revised based on the results of an exploratory factor analysis. In the present study, the revised scale was given to…

Ozturk, Mehmet Ali

2011-01-01

262

Metal Analysis of Scales Taken from Arctic Grayling  

Microsoft Academic Search

This study examined concentrations of metals in fish scales taken from Arctic grayling using laser ablation–inductively coupled\\u000a plasma mass spectrometry (LA-ICPMS). The purpose was to assess whether scale metal concentrations reflected whole muscle metal\\u000a concentrations and whether the spatial distribution of metals within an individual scale varied among the growth annuli of\\u000a the scales. Ten elements (Mg, Ca, Ni, Zn,

A. P. Farrell; A. H. Hodaly; S. Wang

2000-01-01

263

Measuring Mathematics Anxiety: Psychometric Analysis of a Bidimensional Affective Scale  

ERIC Educational Resources Information Center

The purpose of this study is to develop a theoretically and methodologically sound bidimensional affective scale measuring mathematics anxiety with high psychometric quality. The psychometric properties of a 14-item Mathematics Anxiety Scale-Revised (MAS-R) adapted from Betz's (1978) 10-item Mathematics Anxiety Scale were empirically analyzed on a…

Bai, Haiyan; Wang, LihShing; Pan, Wei; Frey, Mary

2009-01-01

264

A New Multi-Dimensional General Relativistic Neutrino Hydrodynamics Code for Core-Collapse Supernovae IV. The Neutrino Signal  

E-print Network

Considering general relativistic, two-dimensional (2D) supernova (SN) explosion models of progenitor stars between 8.1 and 27 solar masses, we systematically analyze the properties of the neutrino emission from core collapse and bounce to the post-explosion phase. The models were computed with the Vertex-CoCoNuT code, using three-flavor, energy-dependent neutrino transport in the ray-by-ray-plus approximation. Our results confirm the close similarity of the mean energies of electron antineutrinos and heavy-lepton neutrinos and even their crossing during the accretion phase for stars with M>10 M_sun as observed in previous 1D and 2D simulations with state-of-the-art neutrino transport. We establish a roughly linear scaling of the electron antineutrino mean energy with the proto-neutron star (PNS) mass, which holds in time as well as for different progenitors. Convection inside the PNS affects the neutrino emission on the 10-20% level, and accretion continuing beyond the onset of the explosion prevents the abrupt drop of the neutrino luminosities seen in artificially exploded 1D models. We demonstrate that a wavelet-based time-frequency analysis of SN neutrino signals in IceCube will offer sensitive diagnostics for the SN core dynamics up to at least ~10kpc distance. Strong, narrow-band signal modulations indicate quasi-periodic shock sloshing motions due to the standing accretion shock instability (SASI), and the frequency evolution of such "SASI neutrino chirps" reveals shock expansion or contraction. The onset of the explosion is accompanied by a shift of the modulation frequency below 40-50Hz, and post-explosion, episodic accretion downflows will be signaled by activity intervals stretching over an extended frequency range in the wavelet spectrogram.

B. Müller; H. -Th. Janka

2014-02-14

265

Scaling Analysis of the Ganges-Brahmaputra River Discharge  

NASA Astrophysics Data System (ADS)

In this study, we characterize the scaling properties of the Ganges-Brahmaputra river discharge. Using 50 years (1950-2000) of in situ measurements of daily discharge at Hardinge (for the Ganges) and Bahadurabad (for the Brahmaputra), we first establish that there is no obvious evidence of the impact of climate change on the discharge of either river; specifically, we find that there is no significant change in the discharge seasonal cycle nor in the variance of their subseasonal fluctuations. Having established weak second order stationarity, we analyse and show that there exists a power-law scaling between 2 days and 60 days for both rivers' normalized discharge fluctuations. The utility of this type of scale-invariance will be illustrated with a temporal disaggregation model, which relates small-scale to large-scale variability (by just a ratio of scales) and enables us to disaggregate 10-day or 35-day discharge estimates from satellite altimetry to the daily scale.

Arulraj, Malarvizhi; Venugopal, V.; Papa, Fabrice; Bala, Sujit K.

2014-05-01

266

Hot spot analysis in large scale shared memory multiprocessors  

SciTech Connect

Scalable multiprocessors that support a shared-memory image to application programmers are typically based on physical memory modules that are distributed. Consequently, the access times for a particular processor to various parts of physical memory differ. In this paper, the authors explore the implications of this non-uniformity in memory access times. In particular, they study the effect of hot-spots in hierarchical large scale NUMA multiprocessors. Hot-spot analysis is of interest because coordinated threads of parallel programs lead to hot spots whose impact on performance may be substantial or even dominant. They have developed an analytical model of access latencies and contention for shared resources in the interconnection network that links the processors and memory modules. Their objective is to provide a better understanding of non-uniform memory access times in scalable architectures. They show the extent to which a variable can be shared before it becomes a performance bottleneck, and assess the potential gain from replication of shared data items. They also demonstrate that the backoff value (after a memory request rejection) must be chosen carefully to balance memory access time and network utilization. Finally, they show that memory utilization is improved by allowing memory request buffering.

Harzallah, K.; Sevcik, K.C. [Univ. of Toronto, Ontario (Canada). Computer Systems Research Institute

1993-12-31

267

MicroScale Thermophoresis: Interaction analysis and beyond  

NASA Astrophysics Data System (ADS)

MicroScale Thermophoresis (MST) is a powerful technique to quantify biomolecular interactions. It is based on thermophoresis, the directed movement of molecules in a temperature gradient, which strongly depends on a variety of molecular properties such as size, charge, hydration shell or conformation. Thus, this technique is highly sensitive to virtually any change in molecular properties, allowing for a precise quantification of molecular events independent of the size or nature of the investigated specimen. During a MST experiment, a temperature gradient is induced by an infrared laser. The directed movement of molecules through the temperature gradient is detected and quantified using either covalently attached or intrinsic fluorophores. By combining the precision of fluorescence detection with the variability and sensitivity of thermophoresis, MST provides a flexible, robust and fast way to dissect molecular interactions. In this review, we present recent progress and developments in MST technology and focus on MST applications beyond standard biomolecular interaction studies. By using different model systems, we introduce alternative MST applications - such as determination of binding stoichiometries and binding modes, analysis of protein unfolding, thermodynamics and enzyme kinetics. In addition, wedemonstrate the capability of MST to quantify high-affinity interactions with dissociation constants (Kds) in the low picomolar (pM) range as well as protein-protein interactions in pure mammalian cell lysates.

Jerabek-Willemsen, Moran; André, Timon; Wanner, Randy; Roth, Heide Marie; Duhr, Stefan; Baaske, Philipp; Breitsprecher, Dennis

2014-12-01

268

MIXREGLS: A Program for Mixed-Effects Location Scale Analysis.  

PubMed

MIXREGLS is a program which provides estimates for a mixed-effects location scale model assuming a (conditionally) normally-distributed dependent variable. This model can be used for analysis of data in which subjects may be measured at many observations and interest is in modeling the mean and variance structure. In terms of the variance structure, covariates can by specified to have effects on both the between-subject and within-subject variances. Another use is for clustered data in which subjects are nested within clusters (e.g., clinics, hospitals, schools, etc.) and interest is in modeling the between-cluster and within-cluster variances in terms of covariates. MIXREGLS was written in Fortran and uses maximum likelihood estimation, utilizing both the EM algorithm and a Newton-Raphson solution. Estimation of the random effects is accomplished using empirical Bayes methods. Examples illustrating stand-alone usage and features of MIXREGLS are provided, as well as use via the SAS and R software packages. PMID:23761062

Hedeker, Donald; Nordgren, Rachel

2013-03-01

269

Numerical Simulation and Scaling Analysis of Cell Printing  

NASA Astrophysics Data System (ADS)

Cell printing, i.e., printing three dimensional (3D) structures of cells held in a tissue matrix, is gaining significant attention in the biomedical community. The key idea is to use inkjet printer or similar devices to print cells into 3D patterns with a resolution comparable to the size of mammalian cells. Achieving such a resolution in vitro can lead to breakthroughs in areas such as organ transplantation. Although the feasibility of cell printing has been demonstrated recently, the printing resolution and cell viability remain to be improved. Here we investigate a unit operation in cell printing, namely, the impact of a cell-laden droplet into a pool of highly viscous liquids. The droplet and cell dynamics are quantified using both direct numerical simulation and scaling analysis. These studies indicate that although cell experienced significant stress during droplet impact, the duration of such stress is very short, which helps explain why many cells can survive the cell printing process. These studies also revealed that cell membrane can be temporarily ruptured during cell printing, which is supported by indirect experimental evidence.

Qiao, Rui; He, Ping

2011-11-01

270

Growth and characterization of a multi-dimensional ZnO hybrid structure on a glass substrate by using metal organic chemical vapor deposition  

NASA Astrophysics Data System (ADS)

A multi-dimensional zinc oxide (ZnO) hybrid structure was successfully grown on a glass substrate by using metal organic chemical vapor deposition (MOCVD). The ZnO hybrid structure was composed of nanorods grown continuously on the ZnO film without any catalysts. The growth mode could be changed from a two-dimensional (2D) film to one-dimensional (1D) nanorods by simply controlling the substrate's temperature. The ZnO with a hybrid structure showed improved electrical and optical properties. The ZnO hybrid structure grown by using MOCVD has excellent potential for applications in opto-electronic devices and solar cells as anti-reflection coatings (ARCs), transparent conductive oxides (TCOs) and transparent thin-film transistors (TTFTs).

Kim, Dae-Sik; Lee, Dohan; Lee, Je-Haeng; Byun, Dongjin

2014-05-01

271

Psychometric analysis of the Yale-Brown Obsessive–Compulsive Scale Second Edition Symptom Checklist  

Microsoft Academic Search

The Yale-Brown Obsessive–Compulsive Scale (Y-BOCS) was recently revised to address several clinical and conceptual issues. The resultant measure, named the Yale-Brown Obsessive–Compulsive Scale—Second Edition, consists of two primary scales: the Severity Scale and the Symptom Checklist. Although the Severity Scale has been the subject of a comprehensive psychometric analysis, no data have been reported on the psychometric properties of the

Eric A. Storch; Michael J. Larson; Lawrence H. Price; Steven A. Rasmussen; Tanya K. Murphy; Wayne K. Goodman

2010-01-01

272

Scaling analysis of phase-change memory technology  

Microsoft Academic Search

The scaling capability of chalcogenide-based phase-change memory (PCM) is discussed. Experimental and numerical results are presented, showing that the reset current scales down with the device contact area, reaching values as low as 50 ?A. The impact of thermal cross-talk between adjacent bits is investigated, showing that thermal disturbs will not limit the scaling of PCM down to the 65

A. Pirovano; A. L. Lacaita; A. Benvenuti; F. Pellizzer; S. Hudgens; R. Bez

2003-01-01

273

Rating scale analysis and psychometric properties of the Caregiver Self-Efficacy Scale for Transfers.  

PubMed

Parents and caregivers faced with the challenges of transferring children with disability are at risk of musculoskeletal injuries and/or emotional stress. The Caregiver Self-Efficacy Scale for Transfers (CSEST) is a 14-item questionnaire that measures self-efficacy for transferring under common conditions. The CSEST yields reliable data and valid inferences; however, its rating scale structure has not been evaluated for utility. The aims of this study were to evaluate the category response structure of the CSEST, test the utility of a revised rating scale structure, and confirm its psychometric properties. The Rasch Measurement Model was used for all analyses. Subjects included 175 adult caregivers recruited from multiple communities. Results confirm that a revised five-category rating scale structure yields reliable data and valid inferences. Given the relationship between self-efficacy and risk of physical and/or emotional stress, measuring parental self-efficacy for transfers is a proactive process in rehabilitation. PMID:22712478

Cipriani, Daniel J; Hensen, Francine E; McPeck, Danielle L; Kubec, Gina L D; Thomas, Julie J

2012-11-01

274

Analysis, scale modeling, and full-scale test of a railcar and spent-nuclear-fuel shipping cask in a high-velocity impact against a rigid barrier  

SciTech Connect

This report describes the mathematical analysis, the physical scale modeling, and a full-scale crash test of a railcar spent-nuclear-fuel shipping system. The mathematical analysis utilized a lumped-parameter model to predict the structural response of the railcar and the shipping cask. The physical scale modeling analysis consisted of two crash tests that used 1/8-scale models to assess railcar and shipping cask damage. The full-scale crash test, conducted with retired railcar equipment, was carefully monitored with onboard instrumentation and high-speed photography. Results of the mathematical and scale modeling analyses are compared with the full-scale test. 29 figures.

Huerta, M.

1981-06-01

275

GAS MIXING ANALYSIS IN A LARGE-SCALED SALTSTONE FACILITY  

SciTech Connect

Computational fluid dynamics (CFD) methods have been used to estimate the flow patterns mainly driven by temperature gradients inside vapor space in a large-scaled Saltstone vault facility at Savannah River site (SRS). The purpose of this work is to examine the gas motions inside the vapor space under the current vault configurations by taking a three-dimensional transient momentum-energy coupled approach for the vapor space domain of the vault. The modeling calculations were based on prototypic vault geometry and expected normal operating conditions as defined by Waste Solidification Engineering. The modeling analysis was focused on the air flow patterns near the ventilated corner zones of the vapor space inside the Saltstone vault. The turbulence behavior and natural convection mechanism used in the present model were benchmarked against the literature information and theoretical results. The verified model was applied to the Saltstone vault geometry for the transient assessment of the air flow patterns inside the vapor space of the vault region using the potential operating conditions. The baseline model considered two cases for the estimations of the flow patterns within the vapor space. One is the reference nominal case. The other is for the negative temperature gradient between the roof inner and top grout surface temperatures intended for the potential bounding condition. The flow patterns of the vapor space calculated by the CFD model demonstrate that the ambient air comes into the vapor space of the vault through the lower-end ventilation hole, and it gets heated up by the Benard-cell type circulation before leaving the vault via the higher-end ventilation hole. The calculated results are consistent with the literature information. Detailed results and the cases considered in the calculations will be discussed here.

Lee, S

2008-05-28

276

Hydrodynamic Scaling Analysis of Nuclear Fusion in Hot Plasma  

E-print Network

Proton beams generated by ultraintense laser pulse irradiations have potential applications in industry and in medicine. However, the laser pulse parameters are currently not optimized for practical applications. We discuss scaling laws of fusion yields generated by laser-plasma interactions. The yields are found to scale as a function of the laser power. The origin of the scaling law in the laser driven fusion yield is derived in terms of hydrodynamical scaling and it is attributed to the laser power dependence of three terms: the reaction rate, the density of the plasma and the pro- jected range of the plasma particle in the medium. The resulting scaling relations have a powerful predictive power that enables estimating the fusion yield for a nuclear reaction which has not been investigated by means of the laser accelerated ion beams.

Kimura, Sachie

2011-01-01

277

Analysis of small scale turbulent structures and the effect of spatial scales on gas transfer  

NASA Astrophysics Data System (ADS)

The exchange of gases through the air-sea interface strongly depends on environmental conditions such as wind stress and waves which in turn generate near surface turbulence. Near surface turbulence is a main driver of surface divergence which has been shown to cause highly variable transfer rates on relatively small spatial scales. Due to the cool skin of the ocean, heat can be used as a tracer to detect areas of surface convergence and thus gather information about size and intensity of a turbulent process. We use infrared imagery to visualize near surface aqueous turbulence and determine the impact of turbulent scales on exchange rates. Through the high temporal and spatial resolution of these types of measurements spatial scales as well as surface dynamics can be captured. The surface heat pattern is formed by distinct structures on two scales - small-scale short lived structures termed fish scales and larger scale cold streaks that are consistent with the footprints of Langmuir Circulations. There are two key characteristics of the observed surface heat patterns: 1. The surface heat patterns show characteristic features of scales. 2. The structure of these patterns change with increasing wind stress and surface conditions. In [2] turbulent cell sizes have been shown to systematically decrease with increasing wind speed until a saturation at u* = 0.7 cm/s is reached. Results suggest a saturation in the tangential stress. Similar behaviour has been observed by [1] for gas transfer measurements at higher wind speeds. In this contribution a new model to estimate the heat flux is applied which is based on the measured turbulent cell size und surface velocities. This approach allows the direct comparison of the net effect on heat flux of eddies of different sizes and a comparison to gas transfer measurements. Linking transport models with thermographic measurements, transfer velocities can be computed. In this contribution, we will quantify the effect of small scale processes on interfacial transport and relate it to gas transfer. References [1] T. G. Bell, W. De Bruyn, S. D. Miller, B. Ward, K. Christensen, and E. S. Saltzman. Air-sea dimethylsulfide (DMS) gas transfer in the North Atlantic: evidence for limited interfacial gas exchange at high wind speed. Atmos. Chem. Phys. , 13:11073-11087, 2013. [2] J Schnieders, C. S. Garbe, W.L. Peirson, and C. J. Zappa. Analyzing the footprints of near surface aqueous turbulence - an image processing based approach. Journal of Geophysical Research-Oceans, 2013.

Schnieders, Jana; Garbe, Christoph

2014-05-01

278

Scaling and the design of miniaturized chemical-analysis systems  

NASA Astrophysics Data System (ADS)

Micrometre-scale analytical devices are more attractive than their macroscale counterparts for various reasons. For example, they use smaller volumes of reagents and are therefore cheaper, quicker and less hazardous to use, and more environmentally appealing. Scaling laws compare the relative performance of a system as the dimensions of the system change, and can predict the operational success of miniaturized chemical separation, reaction and detection devices before they are fabricated. Some devices designed using basic principles of scaling are now commercially available, and opportunities for miniaturizing new and challenging analytical systems continue to arise.

Janasek, Dirk; Franzke, Joachim; Manz, Andreas

2006-07-01

279

An analysis and validation pipeline for large-scale RNAi-based screens  

E-print Network

performed a large-scale pooled shRNA screen in mouse embryonic stem cells (ESCs) to discover genesAn analysis and validation pipeline for large-scale RNAi-based screens Michael Plank1 , Guang Hu2 Medical School, Boston, MA 02115, USA. Large-scale RNAi-based screens are a major technology, but require

de Magalhães, João Pedro

280

Data mining techniques for large-scale gene expression analysis  

E-print Network

Modern computational biology is awash in large-scale data mining problems. Several high-throughput technologies have been developed that enable us, with relative ease and little expense, to evaluate the coordinated expression ...

Palmer, Nathan Patrick

2011-01-01

281

Markov Chain Analysis for Large-Scale Grid Systems.  

National Technical Information Service (NTIS)

In large-scale grid systems with decentralized control, the interactions of many service providers and consumers will likely lead to emergent global system behaviors that result in unpredictable, often detrimental, outcomes. This possibility argues for de...

C. Dabrowski, F. Hunt

2009-01-01

282

Spectral Analysis for Billion-Scale Graphs: Discoveries and Implementation  

E-print Network

? Are there nodes that participate in too many or too few triangles? Are there close-knit near-scale. In this paper, we discover patterns on near-cliques and triangles, on several real- world graphs including

283

Factor analysis of the WAIS and wechsler memory scale: An analysis of the construct validity of the wechsler memory scale  

Microsoft Academic Search

The WAIS and Wechsler Memory Scale subtest scores of 256 neurologic and nonneurologic subjects were factor analyzed. The results supported the construct validity of the Wechsler Memory Scale as a measure of verbal learning and memory, attention and concentration, and orientation. Construct validity was not demonstrated for the Visual Reproduction subtest as a measure of visual memory. Suggestions are offered

Glenn J. Larrabee; Robert L. Kane; John R. Schuck

1983-01-01

284

Distorted Froude-scaled Flume Analysis of Large Woody Debris  

Microsoft Academic Search

This paper presents the results of a movable-boundary, distorted, Froude-scaled hydraulic model based on Abiaca Creek, a sand-bedded channel in northern Mississippi. The model was used to examine the geomorphic and hydraulic impact of simplified Large Woody Debris (LWD) elements. The theory of physical scale models is discussed and the method used to construct the LWD test channel is developed.

N. P. Wallerstein; C. V. Alonso; S. J. Bennett; C. R. Thorne

2001-01-01

285

CFD analysis of wind climate from human scale to urban scale  

Microsoft Academic Search

The rapid growth of computational wind engineering (CWE) has led to an expansion of the research fields of wind engineering. CWE has made it possible to analyze various physical processes associated with wind climate around humans and in urban areas. This paper reviews recent achievements in CWE and its application to wind climate in scales ranging from human to urban

Shuzo Murakami; Ryozo Ooka; Akashi Mochida; Shinji Yoshida; Sangjin Kim

1999-01-01

286

A Comparative Scaling Analysis of Metallic and Carbon Nanotube Interconnections for Nanometer Scale VLSI Technologies  

Microsoft Academic Search

This paper addresses the critical issue of scaling limits of local interconnects, contact plugs and local vias made of metal. It is shown that the current carrying capacity of copper vias\\/contacts fails to meet ITRS cur- rent density requirements beyond the 45 nm technology node. Additionally, the electrical properties of local interconnects\\/vias made of carbon nanotube (CNT) ar- rays are

Navin Srivastava; Kaustav Banerjee

287

Rating Scale Analysis and Psychometric Properties of the Caregiver Self-Efficacy Scale for Transfers  

ERIC Educational Resources Information Center

Parents and caregivers faced with the challenges of transferring children with disability are at risk of musculoskeletal injuries and/or emotional stress. The Caregiver Self-Efficacy Scale for Transfers (CSEST) is a 14-item questionnaire that measures self-efficacy for transferring under common conditions. The CSEST yields reliable data and valid…

Cipriani, Daniel J.; Hensen, Francine E.; McPeck, Danielle L.; Kubec, Gina L. D.; Thomas, Julie J.

2012-01-01

288

Scales  

ScienceCinema

Musical scales involve notes that, sounded simultaneously (chords), sound good together. The result is the left brain meeting the right brain ? a Pythagorean interval of overlapping notes. This synergy would suggest less difference between the working of the right brain and the left brain than common wisdom would dictate. The pleasing sound of harmony comes when two notes share a common harmonic, meaning that their frequencies are in simple integer ratios, such as 3/2 (G/C) or 5/4 (E/C).

Murray Gibson

2010-01-08

289

Multiscale Modeling and TimeScale Analysis of a Human Limb  

Microsoft Academic Search

A multi-scale modeling approach is proposed in this paper that assists the user in constructing musculoskeletal system models from sub-models describing various mechanisms on different levels on the length scale. In addition, dynamic time-scale analysis has been performed on the developed multi-scale models of various parts of a human limb: on wrist, elbow and shoulder characterized by different maximal muscle

Csaba Fazekas; ORGY KOZMANN; Katalin M. Hangos

2007-01-01

290

Scaling behavior of high resolution temporal rainfall: New insights from a wavelet-based cumulant analysis  

Microsoft Academic Search

We revisit the multifractal analysis of high resolution temporal rainfall using the wavelet transform modulus maxima (WTMM) method. Specifically, we employ a cumulant analysis of the logarithm of the WTMM coefficients to estimate the scaling exponent spectrum ?(q) and the spectrum of singularities D(h). We document that rainfall intensity fluctuations exhibit multifractality from scales of the order of 4–5 minutes

V. Venugopal; Stéphane G. Roux; Efi Foufoula-Georgiou; Alain Arnéodo

2006-01-01

291

Genome-Scale Analysis of Saccharomyces cerevisiae Metabolism and Ethanol Production  

E-print Network

ARTICLE Genome-Scale Analysis of Saccharomyces cerevisiae Metabolism and Ethanol Production in Fed Periodicals, Inc. KEYWORDS: Saccharomyces cerevisiae; dynamic flux bal- ance analysis; genome-scale metabolic targets that are experimen- tally testable. In a recent study with a Saccharomyces cerevisiae genome

Mountziaris, T. J.

292

Typological and factor analysis of the perceived stress measure by using the PSS scale  

Microsoft Academic Search

The aim of this research was to explore the structure of the Perceived Stress Scale (PSS) by using data analysis in order to question its theoretical and methodological bases in a critical and positive way. Unidimensional analyses and two-dimensional analyses of the scale were carried out on a sample of 600 individuals. The typological analysis of the data subsequently made

A. Cerclé; C. Gadéa; A. Hartmann; M. Lourel

2008-01-01

293

Scale Development Research: A Content Analysis and Recommendations for Best Practices  

ERIC Educational Resources Information Center

The authors conducted a content analysis on new scale development articles appearing in the "Journal of Counseling Psychology" during 10 years (1995 to 2004). The authors analyze and discuss characteristics of the exploratory and confirmatory factor analysis procedures in these scale development studies with respect to sample characteristics,…

Worthington, Roger L.; Whittaker, Tiffany A.

2006-01-01

294

QA-Pagelet: Data Preparation Techniques for Large-Scale Data Analysis of the Deep Web  

E-print Network

QA-Pagelet: Data Preparation Techniques for Large-Scale Data Analysis of the Deep Web James the QA-Pagelet as a fundamental data preparation technique for large-scale data analysis of the Deep Web-Pagelets from the Deep Web. Two unique features of the Thor framework are 1) the novel page clustering

Caverlee, James

295

QA-Pagelet: Data Preparation Techniques for Large Scale Data Analysis of the Deep Web  

E-print Network

1 QA-Pagelet: Data Preparation Techniques for Large Scale Data Analysis of the Deep Web James data preparation technique for large scale data analysis of the Deep Web. To support QA the Deep Web. Two unique features of the Thor framework are (1) the novel page clustering for grouping

Liu, Ling

296

Large-Scale Cancer Genomics Data Analysis - David Haussler, TCGA Scientific Symposium 2011  

Cancer.gov

Home News and Events Multimedia Library Videos Large-Scale Cancer Genomics Data Analysis - David Haussler Large-Scale Cancer Genomics Data Analysis - David Haussler, TCGA Scientific Symposium 2011 You will need Adobe Flash Player 8 or later and JavaScript

297

Measuring the Measure: A Multi-dimensional Scale Model to Measure Community Disaster Resilience in the U.S. Gulf Coast Region  

E-print Network

........................................... 160 Figure 8.2 Spatial distribution patterns of CDRI-2 scores........................................... 161 Figure 8.3 Spatial distribution patterns of CDRI-3 scores........................................... 162 Figure 8.4 LISA... cluster map for CDRI-1 .................................................................... 165 Figure 8.5 LISA cluster map for CDRI-2 .................................................................... 166 Figure 8.6 LISA cluster map for CDRI...

Mayunga, Joseph S.

2010-07-14

298

Daylighting Analysis through Scale Model, Full Scale Measurements and Computer Analysis for a Texas A&M University Campus Building  

E-print Network

In the first part of this study, daylighting levles in an actualy classroom are compared to scale model measurements and to computer program predictions. Secondly, the daylighting effects in the building atrium are examined through the studies...

Kim, K. S.; Boyer, L. L.; Degelman, L. O.

1985-01-01

299

Scale Free Analysis and the Prime Number Theorem  

E-print Network

We present an elementary proof of the prime number theorem. The relative error follows a golden ratio scaling law and respects the bound obtained from the Riemann's hypothesis. The proof is derived in the framework of a scale free nonarchimedean extension of the real number system exploiting the concept of relative infinitesimals introduced recently in connection with ultrametric models of Cantor sets. The extended real number system is realized as a completion of the field of rational numbers $Q$ under a {\\em new} nonarchimedean absolute value, which treats arbitrarily small and large numbers separately from a finite real number.

Dhurjati Prasad Datta; Anuja Roy Choudhuri

2010-01-10

300

Analysis of deep inelastic scattering with $z$-dependent scale  

E-print Network

Evolution of the parton densities at NLO in $\\alpha_S$ using $\\tilde W^2 = Q^2 (1-z)/z$ instead of the usual $Q^2$ for the scale of the running coupling $\\alpha_S$ is investigated. While this renormalisation scale change was originally proposed as the relevant one for $x \\to 1$, we explore the consequences for all $x$ with this choice. While it leads to no improvement to the description of DIS data, the nature of the gluon at low $x$, low $Q^2$ is different, avoiding the need for a `valence-like' gluon.

R. G. Roberts

1999-04-13

301

Multi Scale Toggle Contrast Operator Based Image Analysis  

NASA Astrophysics Data System (ADS)

Toggle contrast operator could extract image features and has been used in different applications. In this paper, the toggle contrast operator is used for image decomposition and reconstruction. By using multi scale structuring elements, toggle contrast operator decomposes the original image as different images which contain image features of different scale. Also, the original image could be reconstructed from the decomposed images without any loss. Therefore, this image decomposition and reconstruction method could be used for different applications. An example of image enhancement application has been also demonstrated.

Bai, Xiangzhi; Zhou, Fugen; Liu, Zhaoying; Xue, Bindang; Jin, Ting

302

Theory & motivation Physics Analysis Results Summary Scaled momentum distributions of charged  

E-print Network

Theory & motivation Physics Analysis Results Summary Scaled momentum distributions of charged.morris@cern.ch DIS09 29th April 2009 1 / 18 #12;Theory & motivation Physics Analysis Results Summary Talk outline 1 Theoretical framework: The MLLA and LPHD; Physics motivation. 2 Physics Analysis: Analysis strategy; Data

303

A Multidimensional Scaling Analysis of Holland's Vocational Personality Stereotypes.  

ERIC Educational Resources Information Center

The perceived similarity of Holland's vocational personality stereotypes was examined using the techniques of nonmetric multidimensional scaling. Three job titles (JTs) were selected for each of Holland's stereotypes. These 18 JTs were then randomly paired. The resulting 153 pairs comprised an inventory which was administered to all students in a…

Gross, Leon J.; Farr, S. David

304

Exergy analysis of domestic-scale solar water heaters  

Microsoft Academic Search

Solar water heater is the most popular means of solar energy utilization because of technological feasibility and economic attraction compared with other kinds of solar energy utilization. Earlier assessments of domestic-scale solar water heaters were based on the first thermodynamic law. However, this kind of assessment cannot perfectly describe the performance of solar water heaters, since the essence of energy

Wang Xiaowu; Hua Ben

2005-01-01

305

A Factor Analysis of the Research Self-Efficacy Scale.  

ERIC Educational Resources Information Center

Counseling professionals' and counseling psychology students' interest in performing research seems to be waning. Identifying the impediments to graduate students' interest and participation in research is important if systematic efforts to engage them in research are to succeed. The Research Self-Efficacy Scale (RSES) was designed to measure…

Bieschke, Kathleen J.; And Others

306

A Rasch Analysis of the Teachers Music Confidence Scale  

ERIC Educational Resources Information Center

This article presents a new measure of teachers' confidence to conduct musical activities with young children; Teachers Music Confidence Scale (TMCS). The TMCS was developed using a sample of 284 in-service and pre-service early childhood teachers in Hong Kong Special Administrative Region (HKSAR). The TMCS consisted of 10 musical activities.…

Yim, Hoi Yin Bonnie; Abd-El-Fattah, Sabry; Lee, Lai Wan Maria

2007-01-01

307

The Asian Values Scale: Development, factor analysis, validation, and reliability  

Microsoft Academic Search

Multicultural researchers and theorists have noted that client adherence to culture-of-or igin values plays an important role in the provision of culturally relevant and sensitive psychological services. However, lack of instruments that measure ethnic cultural values has been a shortcoming in past research that attempted to examine this relationship. In this article, the development of the Asian Values Scale (AVS)

Bryan S. K. Kim; Donald R. Atkinson; Peggy H. Yang

1999-01-01

308

Item response analysis of the Positive and Negative Syndrome Scale  

Microsoft Academic Search

BACKGROUND: Statistical models based on item response theory were used to examine (a) the performance of individual Positive and Negative Syndrome Scale (PANSS) items and their options, (b) the effectiveness of various subscales to discriminate among individual differences in symptom severity, and (c) the appropriateness of cutoff scores recently recommended by Andreasen and her colleagues (2005) to establish symptom remission.

Darcy A Santor; Haya Ascher-Svanum; Jean-Pierre Lindenmayer; Robert L Obenchain

2007-01-01

309

Psychometric Analysis of Computer Science Help-Seeking Scales  

Microsoft Academic Search

The purpose of this studywas to develop scales to assess instrumental help seeking, executive help seeking, perceived benefits of help seeking, and avoidance of help seeking and to examine their psychometric properties by conducting factor and reliability analyses. As this is the first attempt to examine the latent structures underlying the measured items, the authors conducted exploratory factor analyses. In

Frank Pajares; Yuk Fai Cheong; Paul Oberman

2004-01-01

310

Acquiescent Responding in Balanced Multidimensional Scales and Exploratory Factor Analysis  

ERIC Educational Resources Information Center

Personality tests often consist of a set of dichotomous or Likert items. These response formats are known to be susceptible to an agreeing-response bias called acquiescence. The common assumption in balanced scales is that the sum of appropriately reversed responses should be reasonably free of acquiescence. However, inter-item correlation (or…

Lorenzo-Seva, Urbano; Rodriguez-Fornells, Antoni

2006-01-01

311

THE USEFULNESS OF SCALE ANALYSIS: EXAMPLES FROM EASTERN MASSACHUSETTS  

EPA Science Inventory

Many water system managers and operators are curious about the value of analyzing the scales of drinking water pipes. Approximately 20 sections of lead service lines were removed in 2002 from various locations throughout the greater Boston distribution system, and were sent to ...

312

The Asian Values Scale: Development, Factor Analysis, Validation, and Reliability  

Microsoft Academic Search

Multicultural researchers and theorists have noted that client adherence to culture-of-origin values plays an important role in the provision of culturally relevant and sensitive psychological services. However, lack of instruments that measure ethnic cultural values has been a shortcoming in past research that attempted to examine this relationship. In this article, the development of the Asian Values Scale (AVS) is

Bryan S. K. Kim; Donald R. Atkinson; Peggy H. Yang

1999-01-01

313

The Asian Values Scale: Development, Factor Analysis, Validation, and Reliability.  

ERIC Educational Resources Information Center

Client adherence to culture-of-origin values plays an important role in the provision of culturally relevant psychological services. Lack of instruments that measure ethnic cultural values has been a shortcoming of past research. Describes development of an Asian Values Scale (AVS) used to measure psychometric measures in four studies. Results…

Kim, Bryan S. K.; Atkinson, Donald R.; Yang, Peggy H.

1999-01-01

314

Mental Models of Text and Film: A Multidimensional Scaling Analysis.  

ERIC Educational Resources Information Center

Reports results of experiment to determine whether mental models are constructed of interrelationships and cross-relationships of character attributions drawn in themes of novels and films. The study used "Animal Farm" in print and cartoon forms. Results demonstrated validity of multidimensional scaling for representing both media. Proposes use of…

Rowell, Jack A.; Moss, Peter D.

1986-01-01

315

Scale Issues in Remote Sensing: A Review on Analysis, Processing and Modeling  

PubMed Central

With the development of quantitative remote sensing, scale issues have attracted more and more the attention of scientists. Research is now suffering from a severe scale discrepancy between data sources and the models used. Consequently, both data interpretation and model application become difficult due to these scale issues. Therefore, effectively scaling remotely sensed information at different scales has already become one of the most important research focuses of remote sensing. The aim of this paper is to demonstrate scale issues from the points of view of analysis, processing and modeling and to provide technical assistance when facing scale issues in remote sensing. The definition of scale and relevant terminologies are given in the first part of this paper. Then, the main causes of scale effects and the scaling effects on measurements, retrieval models and products are reviewed and discussed. Ways to describe the scale threshold and scale domain are briefly discussed. Finally, the general scaling methods, in particular up-scaling methods, are compared and summarized in detail. PMID:22573986

Wu, Hua; Li, Zhao-Liang

2009-01-01

316

Scale issues in remote sensing: a review on analysis, processing and modeling.  

PubMed

With the development of quantitative remote sensing, scale issues have attracted more and more the attention of scientists. Research is now suffering from a severe scale discrepancy between data sources and the models used. Consequently, both data interpretation and model application become difficult due to these scale issues. Therefore, effectively scaling remotely sensed information at different scales has already become one of the most important research focuses of remote sensing. The aim of this paper is to demonstrate scale issues from the points of view of analysis, processing and modeling and to provide technical assistance when facing scale issues in remote sensing. The definition of scale and relevant terminologies are given in the first part of this paper. Then, the main causes of scale effects and the scaling effects on measurements, retrieval models and products are reviewed and discussed. Ways to describe the scale threshold and scale domain are briefly discussed. Finally, the general scaling methods, in particular up-scaling methods, are compared and summarized in detail. PMID:22573986

Wu, Hua; Li, Zhao-Liang

2009-01-01

317

An iterative BEM\\/FVM protocol for steady-state multi-dimensional conjugate heat transfer in compressible flows  

Microsoft Academic Search

A BEM-based temperature forward\\/flux back (TFFB) coupling algorithm is developed to solve the conjugate heat transfer (CHT), which arises naturally in analysis of systems exposed to a convective environment. Here, heat conduction within a structure is coupled to heat transfer to the external fluid, which is convecting heat into or out of the solid structure. There are two basic approaches

E. Divo; E. Steinthorsson; A. J. Kassab; R. Bialecki

2002-01-01

318

FEMVib, an ab initio multi-dimensional solver for probing vibrational dynamics in polyatomic molecules and free radicals  

Microsoft Academic Search

Accurate prediction of the vibrational spectra in polyatomic molecules and free radicals depends on obtaining high quality solutions to the vibrational Schrodinger equation. The quantum simple harmonic oscillator provides the traditional first approximation for modeling molecular vibrational states. Rarely does a vibrational analysis extend beyond this first approximation, and harmonic energy levels are routinely used to predict the infrared spectra

Dong Xu

2008-01-01

319

On the scaling range of power-laws originated from fluctuation analysis  

E-print Network

We extend our previous study of scaling range properties done for detrended fluctuation analysis (DFA) \\cite{former_paper} to other techniques of fluctuation analysis (FA). The new technique called Modified Detrended Moving Average Analysis (MDMA) is introduced and its scaling range properties are examined and compared with those of detrended moving average analysis (DMA) and DFA. It is shown that contrary to DFA, DMA and MDMA techniques exhibit power law dependence of the scaling range with respect to the length of the searched signal and with respect to the accuracy $R^2$ of the fit to the considered scaling law imposed by DMA or MDMA schemes. This power law dependence is satisfied for both uncorrelated and autocorrelated data. We find also a simple generalization of this power law relation for series with different level of autocorrelations measured in terms of the Hurst exponent. Basic relations between scaling ranges for different techniques are also discussed. Our findings should be particularly useful ...

Dariusz, Grech

2012-01-01

320

An Analysis Approach to Large-scale Vehicular Network Simulations  

SciTech Connect

Advances in parallel simulation capabilities are now enabling the possibility of simulating multiple scenarios of large problem configurations. In emergency management applications, for example, it is now conceivable to consider simulating phenomena in large (city- or state-scale) vehicular networks. However, an informed understanding of simulation results is needed for real-time decision support tools that make use a number of simulation runs. Of special interest are insights into trade-offs between accuracy and confidence bounds of simulation results, such as in the quality of predicted evacuation time in emergencies. In some of our emergency management projects, we are exploring approaches that not only aid in making statistically significant interpretations of simulation results but also provide a basis for presenting the inherent qualitative properties of the results to the decision makers. We provide experimental results that demonstrate the possibility of applying our approach to large-scale vehicular network simulations for emergency planning and management.

Perumalla, Kalyan S [ORNL; Beckerman, Martin [ORNL

2007-01-01

321

Gyrokinetic analysis of thermal transport scaling in NSTX and MAST  

NASA Astrophysics Data System (ADS)

It remains unclear how thermal energy confinement will scale when extrapolating from present-day STs to CTF conditions at higher plasma current and toroidal field (lower collisionality). To address this theoretically we present linear gyrokinetic simulations investigating microstability in the outer half-radius of NSTX and MAST discharges that vary Ip and BT. In high collisionality discharges (low Ip & BT) microtearing modes are often predicted to be unstable. These modes are weakened when artificially reducing electron collisionality, consistent with experimental scaling trends at higher Ip & BT. Whether other modes (ITG/TEM, ETG) arise depends on additional parameters such as profile gradients, effective ionic charge, beta, and flux surface shaping. We also discuss the numerical complications in non-linear microtearing mode simulations that include electromagnetic perturbations, collisions and toroidal flow and flow shear. This work is supported by US DOE contract DE-AC02-09CH11466.

Guttenfelder, Walter; Kaye, S. M.; Candy, J.; Bell, R. E.; Leblanc, B. P.; Hammett, G. W.; Mikkelsen, D. R.; Yuh, H.; Field, A. R.; Valovic, M.; Nevins, W. M.; Wang, E.

2010-11-01

322

Analysis plan for 1985 large-scale tests. Technical report  

SciTech Connect

The purpose of this effort is to assist DNA in planning for large-scale (upwards of 5000 tons) detonations of conventional explosives in the 1985 and beyond time frame. Primary research objectives were to investigate potential means to increase blast duration and peak pressures. This report identifies and analyzes several candidate explosives. It examines several charge designs and identifies advantages and disadvantages of each. Other factors including terrain and multiburst techniques are addressed as are test site considerations.

McMullan, F.W.

1983-01-01

323

Numerical analysis of large-scale surface-piercing propellers  

Microsoft Academic Search

Surface-Piercing Propellers (SPPs) are the preferred propulsion system for light to moderately loaded high-speed applications due to the high fuel efficiency. For highly loaded applications, the efficiency of SPPs tends to decrease because of the limited submerged blade area and the presence of large suction side cavities. Moreover, it is a challenge to design large-scale SPPs that can maintain reliable

Yin Lu Young; Brant R. Savander

2011-01-01

324

Numerical analysis of field-scale transport of bromacil  

Microsoft Academic Search

Field-scale transport of bromacil (5-bromo-3-sec-butyl-6-methyluracil) was analyzed using two different model processes for local description of the transport. The first was the classical, one-region convection dispersion equation (CDE) model while the second was the two-region, mobile-immobile (MIM) model. The analyses were performed by means of detailed three-dimensional, numerical simulations of the flow and the transport [Russo, D., Zaidel, J. and

David Russo; Inbar Tauber-Yasur; Asher Laufer; Bruno Yaron

1998-01-01

325

A pseudo-Bertrand distribution for time-scale analysis  

Microsoft Academic Search

Using the pseudo-Wigner time-frequency distribution as a guide, we derive two new time-scale representations: the pseudo-Bertrand and the smoothed pseudo-Bertrand distributions. Unlike the Bertrand distribution, these representations support efficient online operation at the same computational cost as the continuous wavelet transform. Moreover, they take advantage of the affine smoothing inherent in the sliding structure of their implementation to suppress cumbersome

P. Goncalves; R. G. Baraniuk

1996-01-01

326

Analysis of nonionic surfactants in bench-scale biotreater samples  

Microsoft Academic Search

The effluents and activated sludges used in benchscale biotreater units have been analyzed for nonionic alcohol ethoxylates\\u000a and their residues. Separate bench-scale units were fed linear alcohol ethoxylates (AE), highly branched and branched nonylphenol\\u000a ethoxylates. Effluents and sludges were first pretreated by a foam sublation technique to provide a gross separation of surfactants\\u000a from the environmental matrix. This step was

S. T. Dubey; L. Kravetz; J. P. Salanitro

1995-01-01

327

Wavelet multiscale analysis for Hedge Funds: Scaling and strategies  

NASA Astrophysics Data System (ADS)

The wide acceptance of Hedge Funds by Institutional Investors and Pension Funds has led to an explosive growth in assets under management. These investors are drawn to Hedge Funds due to the seemingly low correlation with traditional investments and the attractive returns. The correlations and market risk (the Beta in the Capital Asset Pricing Model) of Hedge Funds are generally calculated using monthly returns data, which may produce misleading results as Hedge Funds often hold illiquid exchange-traded securities or difficult to price over-the-counter securities. In this paper, the Maximum Overlap Discrete Wavelet Transform (MODWT) is applied to measure the scaling properties of Hedge Fund correlation and market risk with respect to the S&P 500. It is found that the level of correlation and market risk varies greatly according to the strategy studied and the time scale examined. Finally, the effects of scaling properties on the risk profile of a portfolio made up of Hedge Funds is studied using correlation matrices calculated over different time horizons.

Conlon, T.; Crane, M.; Ruskin, H. J.

2008-09-01

328

On the Calculation of Stationary Solutions of MultiDimensional Fokker–Planck Equations by Orthogonal Functions  

Microsoft Academic Search

In this paper, nonlinear stochastic systems are investigatedvia associated Fokker–Planck equations. Their stationary solutions arecalculated by expansions into orthogonal functions, e.g. especiallyadjusted polynomials and Fourier series. The weighting functions of thenew polynomials are obtained by the application of the stochasticaveraging method. The proposed analysis is demonstrated with severalexamples. The first one is a two-dimensional problem of nonlinearoscillators driven by white

Utz von Wagner; Walter V. Wedig

2000-01-01

329

Multi-resolution analysis for ENO schemes  

NASA Technical Reports Server (NTRS)

Given an function, u(x), which is represented by its cell-averages in cells which are formed by some unstructured grid, we show how to decompose the function into various scales of variation. This is done by considering a set of nested grids in which the given grid is the finest, and identifying in each locality the coarsest grid in the set from which u(x) can be recovered to a prescribed accuracy. This multi-resolution analysis was applied to essentially non-oscillatory (ENO) schemes in order to advance the solution by one time-step. This is accomplished by decomposing the numerical solution at the beginning of each time-step into levels of resolution, and performing the computation in each locality at the appropriate coarser grid. An efficient algorithm for implementing this program in the 1-D case is presented; this algorithm can be extended to the multi-dimensional case with Cartesian grids.

Harten, Ami

1991-01-01

330

Neuron-Glia Interaction as a Possible Glue to Translate the Mind-Brain Gap: A Novel Multi-Dimensional Approach Toward Psychology and Psychiatry  

PubMed Central

Neurons and synapses have long been the dominant focus of neuroscience, thus the pathophysiology of psychiatric disorders has come to be understood within the neuronal doctrine. However, the majority of cells in the brain are not neurons but glial cells including astrocytes, oligodendrocytes, and microglia. Traditionally, neuroscientists regarded glial functions as simply providing physical support and maintenance for neurons. Thus, in this limited role glia had been long ignored. Recently, glial functions have been gradually investigated, and increasing evidence has suggested that glial cells perform important roles in various brain functions. Digging up the glial functions and further understanding of these crucial cells, and the interaction between neurons and glia may shed new light on clarifying many unknown aspects including the mind-brain gap, and conscious-unconscious relationships. We briefly review the current situation of glial research in the field, and propose a novel translational research with a multi-dimensional model, combining various experimental approaches such as animal studies, in vitro & in vivo neuron-glia studies, a variety of human brain imaging investigations, and psychometric assessments. PMID:24155727

Kato, Takahiro A.; Watabe, Motoki; Kanba, Shigenobu

2013-01-01

331

A WENO-limited, ADER-DT, finite-volume scheme for efficient, robust, and communication-avoiding multi-dimensional transport  

NASA Astrophysics Data System (ADS)

The novel ADER-DT time discretization is applied to two-dimensional transport in a quadrature-free, WENO- and FCT-limited, Finite-Volume context. Emphasis is placed on (1) the serial and parallel computational properties of ADER-DT and this framework and (2) the flexibility of ADER-DT and this framework in efficiently balancing accuracy with other constraints important to transport applications. This study demonstrates a range of choices for the user when approaching their specific application while maintaining good parallel properties. In this method, genuine multi-dimensionality, single-step and single-stage time stepping, strict positivity, and a flexible range of limiting are all achieved with only one parallel synchronization and data exchange per time step. In terms of parallel data transfers per simulated time interval, this improves upon multi-stage time stepping and post-hoc filtering techniques such as hyperdiffusion. This method is evaluated with standard transport test cases over a range of limiting options to demonstrate quantitatively and qualitatively what a user should expect when employing this method in their application.

Norman, Matthew R.

2014-10-01

332

A WENO-Limited, ADER-DT, Finite-Volume Scheme for Efficient, Robust, and Communication-Avoiding Multi-Dimensional Transport  

SciTech Connect

The novel ADER-DT time discretization is applied to two-dimensional transport in a quadrature-free, WENO- and FCT-limited, Finite-Volume context. Emphasis is placed on (1) the serial and parallel computational properties of ADER-DT and this framework and (2) the flexibility of ADER-DT and this framework in efficiently balancing accuracy with other constraints important to transport applications. This study demonstrates a range of choices for the user when approaching their specific application while maintaining good parallel properties. In this method, genuine multi-dimensionality, single-step and single-stage time stepping, strict positivity, and a flexible range of limiting are all achieved with only one parallel synchronization and data exchange per time step. In terms of parallel data transfers per simulated time interval, this improves upon multi-stage time stepping and post-hoc filtering techniques such as hyperdiffusion. This method is evaluated with standard transport test cases over a range of limiting options to demonstrate quantitatively and qualitatively what a user should expect when employing this method in their application.

Norman, Matthew R [ORNL

2014-01-01

333

ThermalScope: Multi-Scale Thermal Analysis For Nanometer-Scale Integrated Circuits  

E-print Network

of heat transfer. Heat transport within nanoscale devices is strongly affected by interface scattering is increasing. The move to nanoscale fabrication processes is increasing the importance of quantum thermal. Existing chip­package thermal analysis methods based on classical Fourier heat transfer cannot capture

Dick, Robert

334

A New Multi-Dimensional General Relativistic Neutrino Hydrodynamics Code for Core-Collapse Supernovae IV. The Neutrino Signal  

E-print Network

Considering general relativistic, two-dimensional (2D) supernova (SN) explosion models of progenitor stars between 8.1 and 27 solar masses, we systematically analyze the properties of the neutrino emission from core collapse and bounce to the post-explosion phase. The models were computed with the Vertex-CoCoNuT code, using three-flavor, energy-dependent neutrino transport in the ray-by-ray-plus approximation. Our results confirm the close similarity of the mean energies of electron antineutrinos and heavy-lepton neutrinos and even their crossing during the accretion phase for stars with M>10 M_sun as observed in previous 1D and 2D simulations with state-of-the-art neutrino transport. We establish a roughly linear scaling of the electron antineutrino mean energy with the proto-neutron star (PNS) mass, which holds in time as well as for different progenitors. Convection inside the PNS affects the neutrino emission on the 10-20% level, and accretion continuing beyond the onset of the explosion prevents the abru...

Mueller, B

2014-01-01

335

Irregularities and Scaling in Signal and Image Processing: Multifractal Analysis  

E-print Network

: Euro-USD rate fluctuations . . . . . . . . . . . . . . . 44 6.3 Fetal Heart Rate Variability analysis proved fruitful, are revisited to illustrate the theoretical developments proposed here. Keywords, Wavelet, Wavelet Leader, Multifractal Spectrum, Hydrody- namic Turbulence, Heart Rate Variability

Paris-Sud XI, Université de

336

Enabling Large-Scale Biomedical Analysis in the Cloud  

PubMed Central

Recent progress in high-throughput instrumentations has led to an astonishing growth in both volume and complexity of biomedical data collected from various sources. The planet-size data brings serious challenges to the storage and computing technologies. Cloud computing is an alternative to crack the nut because it gives concurrent consideration to enable storage and high-performance computing on large-scale data. This work briefly introduces the data intensive computing system and summarizes existing cloud-based resources in bioinformatics. These developments and applications would facilitate biomedical research to make the vast amount of diversification data meaningful and usable. PMID:24288665

Lin, Ying-Chih; Yu, Chin-Sheng; Lin, Yen-Jen

2013-01-01

337

Distorted Froude-scaled Flume Analysis of Large Woody Debris  

NASA Astrophysics Data System (ADS)

This paper presents the results of a movable-boundary, distorted, Froude-scaled hydraulic model based on Abiaca Creek, a sand-bedded channel in northern Mississippi. The model was used to examine the geomorphic and hydraulic impact of simplified Large Woody Debris (LWD) elements. The theory of physical scale models is discussed and the method used to construct the LWD test channel is developed. The channel model had bed and banks molded from 0.8 mm sand, and flow conditions were just below the threshold of motion so that any sediment transport and channel adjustment were the result of the debris element. Dimensions and positions of LWD elements were determined using a Debris Jam Classification Model (Wallerstein et al., 1997). Elements were attached to a dynamometer to measure element drag forces, and channel adjustment was determined through detailed topographic surveys. The fluid drag force on the element decreased asymptotically over time as the channel boundary eroded around the element due to locally increased boundary shear stress. Total time for geomorphic adjustment computed for the prototype channel at the Q2 discharge (discharge occurring once every two years on average) was as short as 45 hours. The size, depth and position of scour holes, bank erosion and bars created by flow acceleration past the elements were found to be related to element length and position within the channel cross-section. Morphologies created by each debris element in the model channel were comparable with similar jams observed in the prototype channel.

Wallerstein, N. P.; Alonso, C. V.; Bennett, S. J.; Thorne, C. R.

2001-12-01

338

Multidimensional scaling modelling approach to latent profile analysis in psychological research  

Microsoft Academic Search

Because profile analysis is widely used in studying types of people, we propose an alternative technique for such analysis in this article. As an application of the multidimensional scaling (MDS) model, MDS profile analysis is proposed as an approach for studying both group and\\/or individual profile patterns. This approach requires one to think of MDS solutions as profiles. The MDS

Cody S. Ding

2006-01-01

339

Construct Validation of the Translated Version of the Work-Family Conflict Scale for Use in Korea  

ERIC Educational Resources Information Center

Recently, the stress of work-family conflict has been a critical workplace issue for Asian countries, especially within those cultures experiencing rapid economic development. Our research purpose is to translate and establish construct validity of a Korean-language version of the Multi-Dimensional Work-Family Conflict (WFC) scale used in the U.S.…

Lim, Doo Hun; Morris, Michael Lane; McMillan, Heather S.

2011-01-01

340

Greatest point rainfall related to duration: Scaling and multifractal analysis in climate model simulations  

NASA Astrophysics Data System (ADS)

The world's greatest observed point rainfall over land P(d) to duration d reveals power law scaling in the d-range of minutes to years, P ~ db with exponent b ~ 0.5. This scaling law analysis is revisited using grid-point data from a state of the art global climate model with different resolution (ECHAM5/MPI-OM T63- and T31-control runs). The following results are noted: (i) the scaling is larger and resolution dependent; the higher resolution is closer to the observed data; (ii) there is almost no land-sea difference in scaling; (iii) a multi-fractal analysis is applied to estimate the related parameters. Causes of the simulation-observation difference are discussed. Keywords: rainfall, scaling law, multifractal analysis, climate simulations

Zhang, H.; Fraedrich, K.

2012-04-01

341

Fifteen new discriminant-function-based multi-dimensional robust diagrams for acid rocks and their application to Precambrian rocks  

NASA Astrophysics Data System (ADS)

For the discrimination of four tectonic settings of island arc, continental arc, within-plate (continental rift and ocean island together), and collision, we present three sets of new diagrams obtained from linear discriminant analysis of natural logarithm transformed ratios of major elements, immobile major and trace elements, and immobile trace elements in acid magmas. The use of discordant outlier-free samples prior to linear discriminant analysis had improved the success rates by about 3% on the average. Success rates of these new diagrams were acceptably high (about 69% to 97% for the first set, about 69% to 99% for the second set, and about 60% to 96% for the third set). Testing of these diagrams for acid rock samples (not used for constructing them) from known tectonic settings confirmed their overall good performance. Application of these new diagrams to Precambrian case studies provided the following generally consistent results: a continental arc setting for the Caribou greenstone belt (Canada) at about 3000 Ma, São Francisco craton (Brazil) at about 3085-2983 Ma, Penakacherla greenstone terrane (Dharwar craton, India) at about 2700 Ma, and Adola (Ethiopia) at about 885-765 Ma; a transitional continental arc to collision setting for the Rio Maria terrane (Brazil) at about 2870 Ma and Eastern felsic volcanic terrain (India) at about 2700 Ma; a collision setting for the Kolar suture zone (India) at about 2610 Ma and Korpo area (Finland) at about 1852 Ma; and a within-plate (likely a continental rift) setting for Malani igneous suite (India) at about 745-700 Ma. These applications suggest utility of the new discrimination diagrams for all four tectonic settings. In fact, all three sets of diagrams were shown to be robust against post-emplacement compositional changes caused by analytical errors, element mobility related to low or high temperature alteration, or Fe-oxidation caused by weathering.

Verma, Surendra P.; Pandarinath, Kailasa; Verma, Sanjeet K.; Agrawal, Salil

2013-05-01

342

A meta-analysis of the validity of the employee attitude inventory theft scales  

Microsoft Academic Search

This article summarizes the criterion-related and construct validity evidence for theEmployee Attitude Inventory (EAI) theft scales. These paper-and-pencil measures were designed to help employers gain information about theft among current employees. It is argued that the validity of the theft scales is dependent on the proportion of dishonest employees in the group being screened. Using meta-analysis techniques, the theft scales

Michael A. McDaniel; John W. Jones

1986-01-01

343

Item factor analysis of the Italian version of the Death Anxiety Scale.  

PubMed

The 15 items of the Italian edition of the Templer's Death Anxiety Scale (DAS) were subjected to a principal components factor analysis with a sample of 257 subjects. Three factors, selected by the scree test, were rotated using the Direct Oblimin procedure. Cronbach alpha-coefficients are reported for the scale and the factors together with their intercorrelations. The results demonstrate that the DAS is a multidimensional scale. Therefore, its utility is questioned. Suggestions are made for future research. PMID:8835696

Saggino, A; Kline, P

1996-05-01

344

Manufacturing Cost Analysis for YSZ-Based FlexCells at Pilot and Full Scale Production Scales  

SciTech Connect

Significant reductions in cell costs must be achieved in order to realize the full commercial potential of megawatt-scale SOFC power systems. The FlexCell designed by NexTech Materials is a scalable SOFC technology that offers particular advantages over competitive technologies. In this updated topical report, NexTech analyzes its FlexCell design and fabrication process to establish manufacturing costs at both pilot scale (10 MW/year) and full-scale (250 MW/year) production levels and benchmarks this against estimated anode supported cell costs at the 250 MW scale. This analysis will show that even with conservative assumptions for yield, materials usage, and cell power density, a cost of $35 per kilowatt can be achieved at high volume. Through advancements in cell size and membrane thickness, NexTech has identified paths for achieving cell manufacturing costs as low as $27 per kilowatt for its FlexCell technology. Also in this report, NexTech analyzes the impact of raw material costs on cell cost, showing the significant increases that result if target raw material costs cannot be achieved at this volume.

Scott Swartz; Lora Thrun; Robin Kimbrell; Kellie Chenault

2011-05-01

345

Experimental and theoretical analysis of a small scale thermoacoustic cooler driven by two sources  

E-print Network

Experimental and theoretical analysis of a small scale thermoacoustic cooler driven by two sources by scaling down thermoacoustic coolers to provide practical solutions for thermal heat management, especially diameter d = 9.4 cm. A thermoacoustic core (stack or regenerator, without any heat exchangers) is set

Paris-Sud XI, Université de

346

Scale and accessibility: Implications for the analysis of land use–travel interaction  

Microsoft Academic Search

An important methodological issue in accessibility research is how the results are affected by geographical scale. Understanding the scale effect and the associated modifiable areal unit problem (MAUP) is also important for the analysis of land use–travel interaction. Using a distinct type of accessibility measures, namely space–time measures, this study examines whether the relationships among accessibility, land use, and personal

Mei-Po Kwan; Joe Weber

2008-01-01

347

New paradigm in protein function prediction for large scale omics analysis  

E-print Network

New paradigm in protein function prediction for large scale omics analysis Troy Hawkins,a Meghana Chitaleb and Daisuke Kihara*abc DOI: 10.1039/b718229e Biological interpretation of large scale omics data to provide large coverage in function prediction, namely omics data driven approaches and a thorough data

Kihara, Daisuke

348

Effects of Mode Selection, Scaling, and Orthogonalization on the Dynamic Analysis of Flexible Multibody Systems  

Microsoft Academic Search

This paper analyzes the effects of mode selection, scaling, and orthogonalization on dynamic analysis of flexible mechanical systems. The effects of mode selection are investigated by combining attachment modes and constraint modes with vibration normal modes to represent elastic deformations of flexible components. Four sets of input data that depend on the options for mode scaling and orthogonalization are generated.

Sang-Hoon Shin; Wan-Suk Yoo; Jun Tang

1993-01-01

349

Common Space Analysis of Several Versions of The Wechsler Intelligence Scale For Children  

Microsoft Academic Search

A joint analysis was made of three versions of the Wechsler Intelligence Scale for Children using an individual differences multidimensional scaling ap proach. The versions of the test considered were the original version, an Australian partial revision, and the current revised version. Common Space Analy sis of the correlation data from the manuals showed a common three-dimensional structure. There was

Richard C. Bell

1981-01-01

350

Multi-scale Complexity Analysis on the Sequence of E. coli Complete Genome  

E-print Network

Multi-scale Complexity Analysis on the Sequence of E. coli Complete Genome Jin Wang1 , Qidong Zhang of E. coli and provided a foldout with the arrangeme-scale density distribution of nucleotides from the complete Escherichia coli genome by applying the newly

Ren, Kui

351

Scaling Analysis of the Thermal Boundary Layer Adjacent to an Abruptly Heated Inclined Flat Plate  

Microsoft Academic Search

The natural convection thermal boundary layer adjacent to an abruptly heated inclined flat plate is investigated through a scaling analysis and verified by numerical simulations. In general, the development of the thermal flow can be characterized by three distinct stages, i.e. a start-up stage, a transitional stage and a steady state stage. Major scales including the flow velocity, flow development

S. C. Saha; C. Lei; J. C. Patterson

352

Scaling analysis of multilevel interconnect temperatures for high-performance ICs  

Microsoft Academic Search

This paper presents a comprehensive thermal scaling analysis of multilevel interconnects in deep nanometer scale CMOS technologies based on technological, structural, and material data from the International Technology Roadmap for Semiconductors. Numerical simulations have been performed using three-dimensional electrothermal finite element methods, combined with accurate calculations of temperature- and size-dependent Cu resistivity and thermal conductivity of low-? interlayer dielectrics (ILD)

Sungjun Im; N. Srivastava; K. Banerjee; K. E. Goodson

2005-01-01

353

Comparative BTI Reliability Analysis of SRAM Cell Designs in Nano-Scale CMOS Technology  

E-print Network

Comparative BTI Reliability Analysis of SRAM Cell Designs in Nano-Scale CMOS Technology Shreyas. BTI affects the stability and reliability of conventional six transistor (6T) SRAM design in nano-scale CMOS technology. Eight transistor (8T) and Ten transistor (10T) SRAM cell de- signs are known

Mahmoodi, Hamid

354

Are Exaggerated Health Complaints Continuous or Categorical? A Taxometric Analysis of the Health Problem Overstatement Scale  

ERIC Educational Resources Information Center

A taxometric analysis of 3 factor scales extracted from the Health Problem Overstatement (HPO) scale of the Psychological Screening Inventory (PSI; R. I. Lanyon, 1970, 1978) was performed on the data from 1,240 forensic and psychiatric patients. Mean above minus below a cut, maximum covariance, and latent-mode factor analyses produced results…

Walters, Glenn D.; Berry, David T. R.; Lanyon, Richard I.; Murphy, Michael P.

2009-01-01

355

Large-Scale Gene Expression Data Analysis: A New Challenge to Computational Biologists  

E-print Network

Large-Scale Gene Expression Data Analysis: A New Challenge to Computational Biologists Michael Q arrays to monitor gene expression at a genome-wide scale constitutes a fundamental advance in biology. In particular, the expression pattern of all genes in Saccharomyces cerevisiae can be interrogated using

356

Exploring children's face-space: A multidimensional scaling analysis of the mental representation of facial identity  

E-print Network

Exploring children's face-space: A multidimensional scaling analysis of the mental representation recognition Visual memory Multidimensional scaling Similarity judgments Face-space a b s t r a c t We explored similarity of faces in a multidimensional space. Five dimensions accounted optimally for the judgments

Maurer, Daphne M.

357

A confirmatory factor analysis of the Self-Directed Learning Readiness Scale.  

PubMed

The Self-Directed Learning Readiness Scale measures readiness for self-directed learning among undergraduate healthcare students. While several exploratory factor analyses and one confirmatory factor analysis have examined the psychometric properties of the Self-Directed Learning Readiness Scale, questions have been raised regarding the underlying latent constructs being measured. The objective of this study was to determine the best-fitting Self-Directed Learning Readiness Scale factorial structure among three models published in the literature. Data from the three-factor 40-item Self-Directed Learning Readiness Scale completed by 233 undergraduate paramedic students from four Australian universities (response rate of 26%) were analyzed using maximum likelihood confirmatory factor analysis. Comparison of model fit from the 40-item version was undertaken with the previously documented four-factor 36-item and three-factor 29-item Self-Directed Learning Readiness Scales. The model fit indices of the three one-factor congeneric models with maximum likelihood analysis demonstrate that the 40-item Self-Directed Learning Readiness Scale does not fit the data well. The best fitting model was the four-factor 36-item Self-Directed Learning Readiness Scale followed by the three-factor 29-item models. The confirmatory factor analysis results did not support the overall construct validity of the original 40-item Self-Directed Learning Readiness Scale. PMID:23552081

Williams, Brett; Brown, Ted

2013-12-01

358

An empirical analysis of an alternative configuration of the Academic Motivation Scale  

Microsoft Academic Search

The purpose of this study was to examine an alternative configuration of the Academic Motivation Scale (AMS), a psychometric instrument used as a measure of academic motivation in various academic environments. The analyses utilised data from a convenience sample of 2354 business students, broken into two random subsamples of 1177 cases. Exploratory factor analysis of the 28 AMS scale items

Kenneth J. Smith; Jeanette A. Davy; Donald L. Rosenberg

2012-01-01

359

Pre-site Characterization Risk Analysis for Commercial-Scale Carbon Sequestration  

E-print Network

Pre-site Characterization Risk Analysis for Commercial-Scale Carbon Sequestration Zhenxue Dai a probability framework to evaluate subsurface risks associated with commercial-scale carbon sequestration to the atmosphere.1-3 The Big Sky Carbon Sequestration Partnership (BSCSP) is one of seven partnerships tasked

Lu, Zhiming

360

Robust Mokken Scale Analysis by Means of the Forward Search Algorithm for Outlier Detection  

ERIC Educational Resources Information Center

Exploratory Mokken scale analysis (MSA) is a popular method for identifying scales from larger sets of items. As with any statistical method, in MSA the presence of outliers in the data may result in biased results and wrong conclusions. The forward search algorithm is a robust diagnostic method for outlier detection, which we adapt here to…

Zijlstra, Wobbe P.; van der Ark, L. Andries; Sijtsma, Klaas

2011-01-01

361

Multi-dimensional modelling of electrostatic force distance curve over dielectric surface: Influence of tip geometry and correlation with experiment  

NASA Astrophysics Data System (ADS)

Electric Force-Distance Curves (EFDC) is one of the ways whereby electrical charges trapped at the surface of dielectric materials can be probed. To reach a quantitative analysis of stored charge quantities, measurements using an Atomic Force Microscope (AFM) must go with an appropriate simulation of electrostatic forces at play in the method. This is the objective of this work, where simulation results for the electrostatic force between an AFM sensor and the dielectric surface are presented for different bias voltages on the tip. The aim is to analyse force-distance curves modification induced by electrostatic charges. The sensor is composed by a cantilever supporting a pyramidal tip terminated by a spherical apex. The contribution to force from cantilever is neglected here. A model of force curve has been developed using the Finite Volume Method. The scheme is based on the Polynomial Reconstruction Operator—PRO-scheme. First results of the computation of electrostatic force for different tip-sample distances (from 0 to 600 nm) and for different DC voltages applied to the tip (6 to 20 V) are shown and compared with experimental data in order to validate our approach.

Boularas, A.; Baudoin, F.; Villeneuve-Faure, C.; Clain, S.; Teyssedre, G.

2014-08-01

362

Meta-Analysis of Scale Reliability Using Latent Variable Modeling  

ERIC Educational Resources Information Center

A latent variable modeling approach is outlined that can be used for meta-analysis of reliability coefficients of multicomponent measuring instruments. Important limitations of efforts to combine composite reliability findings across multiple studies are initially pointed out. A reliability synthesis procedure is discussed that is based on…

Raykov, Tenko; Marcoulides, George A.

2013-01-01

363

Optimization of Large Scale HEP Data Analysis in LHCb  

NASA Astrophysics Data System (ADS)

Observation has lead to a conclusion that the physics analysis jobs run by LHCb physicists on a local computing farm (i.e. non-grid) require more efficient access to the data which resides on the Grid. Our experiments have shown that the I/O bound nature of the analysis jobs in combination with the latency due to the remote access protocols (e.g. rfio, dcap) cause a low CPU efficiency of these jobs. In addition to causing a low CPU efficiency, the remote access protocols give rise to high overhead (in terms of amount of data transferred). This paper gives an overview of the concept of pre-fetching and caching of input files in the proximity of the processing resources, which is exploited to cope with the I/O bound analysis jobs. The files are copied from Grid storage elements (using GridFTP), while concurrently performing computations, inspired from a similar idea used in the ATLAS experiment. The results illustrate that this file staging approach is relatively insensitive to the original location of the data, and a significant improvement can be achieved in terms of the CPU efficiency of an analysis job. Dealing with scalability of such a solution on the Grid environment is discussed briefly.

Remenska, Daniela; Aaij, Roel; Raven, Gerhard; Merk, Marcel; Templon, Jeff; Bril, Reinder J.; LHCb Collaboration

2011-12-01

364

Nat Genet . Author manuscript Large-scale genome-wide association analysis of bipolar disorder  

E-print Network

Nat Genet . Author manuscript Page /1 12 Large-scale genome-wide association analysis of bipolar disorder identifies a new susceptibility locus near ODZ4 Pamela Sklar 1 2 * , Stephan Ripke 2 3 , Laura J

Boyer, Edmond

365

Brief Psychometric Analysis of the Self-Efficacy Teacher Report Scale  

ERIC Educational Resources Information Center

This study provides preliminary analysis of reliability and validity of scores on the Self-Efficacy Teacher Report Scale, which was designed to assess teacher perceptions of self-efficacy of students aged 8 to 17 years. (Contains 3 tables.)

Erford, Bradley T.; Duncan, Kelly; Savin-Murphy, Janet

2010-01-01

366

Large-Scale Comparative Analysis of Pertussis Population Dynamics: Periodicity, Synchrony, and Impact of Vaccination  

E-print Network

Large-Scale Comparative Analysis of Pertussis Population Dynamics: Periodicity, Synchrony, 2004; accepted for publication February 9, 2005. Pertussis is a worldwide infectious disease which view of pertussis dynamics and the impact of vaccination, the authors performed, using the wavelet

Roche, Benjamin

367

Scale dependencies in structural analysis as illustrated by chevron folds along the Beartooth Front, Wyoming  

E-print Network

SCALE DEPENDENCIES IN STRUCTURAL ANALYSIS AS ILLUSTRATED BY CHEVRON FOLDS ALONG THE BEARTOOTH FRONT, WYOMING A Thesis ROBERT ANNAN COOK Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement..., for the degree of MASTER OF SCIENCE August 1972 Ma)or Sub)oct: Geology SCALE DEPENDENCIES IN STRUCTURAL ANALYSIS AS ILLUSTRATED BY CHEVRON FOLDS ALONG THE BEARTOOTH FRONT, WYOMING A Thesis by ROBERT ANNAN COOK Approved as to style and content by...

Cook, Robert Annan

2012-06-07

368

Factor Analysis of the Omega Scale: A Scale Designed To Measure the Attitudes of College Students toward Their Own Deaths and the Disposition of Their Bodies.  

ERIC Educational Resources Information Center

A study was undertaken to provide a factor analysis of the Omega Scale, a 25-item, Likert-type scale developed in 1984 to assess attitudes toward death and funerals and other body disposition practices. The Omega Scale was administered to 250 students enrolled in introductory psychology classes at two higher education institutions in Alabama.…

Staik, Irene M.

369

Large-scale identification and analysis of suppressive drug interactions.  

PubMed

One drug may suppress the effects of another. Although knowledge of drug suppression is vital to avoid efficacy-reducing drug interactions or discover countermeasures for chemical toxins, drug-drug suppression relationships have not been systematically mapped. Here, we analyze the growth response of Saccharomyces cerevisiae to anti-fungal compound ("drug") pairs. Among 440 ordered drug pairs, we identified 94 suppressive drug interactions. Using only pairs not selected on the basis of their suppression behavior, we provide an estimate of the prevalence of suppressive interactions between anti-fungal compounds as 17%. Analysis of the drug suppression network suggested that Bromopyruvate is a frequently suppressive drug and Staurosporine is a frequently suppressed drug. We investigated potential explanations for suppressive drug interactions, including chemogenomic analysis, coaggregation, and pH effects, allowing us to explain the interaction tendencies of Bromopyruvate. PMID:24704506

Cokol, Murat; Weinstein, Zohar B; Yilancioglu, Kaan; Tasan, Murat; Doak, Allison; Cansever, Dilay; Mutlu, Beste; Li, Siyang; Rodriguez-Esteban, Raul; Akhmedov, Murodzhon; Guvenek, Aysegul; Cokol, Melike; Cetiner, Selim; Giaever, Guri; Iossifov, Ivan; Nislow, Corey; Shoichet, Brian; Roth, Frederick P

2014-04-24

370

Welfare effects of natural disasters in developing countries: an examination using multi-dimensional socio-economic indicators  

NASA Astrophysics Data System (ADS)

The study of the socio-economic impacts of natural disasters is still in its infancy. Social scientists have historically regarded natural disasters as exogenous or essentially random perturbations. More recent scholarship treats disaster shocks as endogenous, with pre-existing social, economic and political conditions determining the form and magnitude of disaster impacts. One apparently robust conclusion is that direct economic losses from natural disasters, similar to human losses, are larger (in relative terms) the poorer a country is, yet cross-country regressions show that disasters may accrue economic benefits due to new investments in productive infrastructure, especially if the investment is funded by externally provided capital (Work Bank assistance, private donations, etc) and do not deplete national savings or acquire a debt burden. Some econometric studies also show that the quality of a country's institutions can mitigate the mortality effects of a disaster. The effects on income inequality are such that the poor suffer greater 'asset shocks' and may never recover from a disaster leading to a widening of existing disparities. Natural disasters affect women more adversely than men in terms of life expectancy at birth. On average they kill more women than men or kill women at a younger age than men, and the more so the stronger the disaster. The extent to which women are more likely to die than men or to die at a younger age from the immediate disaster impact or from post-disaster events depends not only on disaster strength itself but also on the socioeconomic status of women in the affected country. Existing research on the economic effects of disasters focus almost exclusively on the impact on economic growth - the growth rate of GDP. GDP however is only a partial indicator of welfare, especially for countries that are in the lower ranks of development status. Very poor communities are typically involved in subsistence level activities or in the informal economy and will not register disaster set backs in GDP accounts. The alterations to their lives can include loss of livelihood, loss of key assets such as livestock, loss of property and loss of savings, reduced life expectancy among survivors, increased poverty rates, increased inequality, greater subsequent maternal and child mortality (due to destruction of health care facilities), reduced education attainment (lack of school buildings), increased gender-based violence and psychological ailments. Our study enhances this literature in two ways. Firstly, it examines the effects of disasters on human development and poverty using cross-country econometric analysis with indicators of welfare that go beyond GDP. We aim to search the impact of disasters on human development and absolute poverty. Secondly we use Peak Ground Acceleration for earthquakes, a modified Palmer Drought Severity and Hurricane Energy rather than disaster event occurrence to account for the severity of the disaster.

Mutter, J. C.; Deraniyagala, S.; Mara, V.; Marinova, S.

2011-12-01

371

Temporal scaling analysis: Viscoelastic properties of star polymers  

NASA Astrophysics Data System (ADS)

A generalized temporal scaling ansatz for the frequency dependence of the loss and storage moduli and for the shear dependence of the viscosity is tested against studies on entangled solutions of star polymers in good and theta solvents. At lower frequencies or shear rates, the ansatz calls for an exponential or stretched-exponential form [e.g., G0 exp(-???)] for G''(?)/? and G'(?)/?2, and correspondingly in ? for ?(?). At higher frequencies, the ansatz indicates that each of these quantities has a power-law dependence on its primary variable. The predicted forms are in excellent agreement with literature data on solutions of poly-?-methylstyrene, polybutadiene, polystyrene, and polyisoprene stars. A power-law correlation ?~G02/3 is observed between the zero-frequency, zero-shear modulus G0 and the low-frequency or low-shear decay constant ? of the stretched exponential, the same power-law line describing both star and linear polymers in good solvents.

Phillies, George D. J.

1999-11-01

372

ANALYSIS OF TURBULENT MIXING JETS IN LARGE SCALE TANK  

SciTech Connect

Flow evolution models were developed to evaluate the performance of the new advanced design mixer pump for sludge mixing and removal operations with high-velocity liquid jets in one of the large-scale Savannah River Site waste tanks, Tank 18. This paper describes the computational model, the flow measurements used to provide validation data in the region far from the jet nozzle, the extension of the computational results to real tank conditions through the use of existing sludge suspension data, and finally, the sludge removal results from actual Tank 18 operations. A computational fluid dynamics approach was used to simulate the sludge removal operations. The models employed a three-dimensional representation of the tank with a two-equation turbulence model. Both the computational approach and the models were validated with onsite test data reported here and literature data. The model was then extended to actual conditions in Tank 18 through a velocity criterion to predict the ability of the new pump design to suspend settled sludge. A qualitative comparison with sludge removal operations in Tank 18 showed a reasonably good comparison with final results subject to significant uncertainties in actual sludge properties.

Lee, S; Richard Dimenna, R; Robert Leishear, R; David Stefanko, D

2007-03-28

373

Development of a statistical sampling method for uncertainty analysis with SCALE  

SciTech Connect

A new statistical sampling sequence called Sampler has been developed for the SCALE code system. Random values for the input multigroup cross sections are determined by using the XSUSA program to sample uncertainty data provided in the SCALE covariance library. Using these samples, Sampler computes perturbed self-shielded cross sections and propagates the perturbed nuclear data through any specified SCALE analysis sequence, including those for criticality safety, lattice physics with depletion, and shielding calculations. Statistical analysis of the output distributions provides uncertainties and correlations in the desired responses. (authors)

Williams, M.; Wiarda, D.; Smith, H.; Jessee, M. A.; Rearden, B. T. [Oak Ridge National Laboratory, P.O Box 2008, Oak Ridge, TN 37831-6354 (United States); Zwermann, W.; Klein, M.; Pautz, A.; Krzykacz-Hausmann, B.; Gallner, L. [Gesellschaft fuer Anlagen- und Reaktorsicherheit GRS, Forschungszentrum, Boltzmannstrasse 14, 85748 Garching (Germany)

2012-07-01

374

Multi-scale analysis of water alteration on the rockslope stability framework  

NASA Astrophysics Data System (ADS)

Water is an important weathering factor on rock discontinuities and in rock mass mechanical behaviour because of its chemical features such as temperature, pH or salinity which make it a "good" candidate to rock degradation. Furthermore the increase of rainfall frequency or intensity highlights some problems on the rock slope stability analysis. This study aims to evaluate the effect of water flow on the rock slope stability and it is performed at two space scales: in situ scale and laboratory (micro scale and macro scale). It shows how water induces degradation at multi-scale (surface roughness and matrix) and thus may decrease the stability of the discontinuous rock mass. It has two main components: the effect of water-solid chemical mechanisms and the analysis of the mechanical response of the discontinuity modified by the water alteration.

Dochez, Sandra; Laouafa, Farid; Franck, Christian; Guedon, Sylvine; Martineau, François; D'Amato, Julie; Saintenoy, Albane

2014-10-01

375

AdS and stabilized extra dimensions in multi-dimensional gravitational models with nonlinear scalar curvature terms R-1 and R4  

NASA Astrophysics Data System (ADS)

We study multi-dimensional gravitational models with scalar curvature nonlinearities of types R-1 and R4. It is assumed that the corresponding higher dimensional spacetime manifolds undergo a spontaneous compactification to manifolds with a warped product structure. Special attention has been paid to the stability of the extra-dimensional factor spaces. It is shown that for certain parameter regions the systems allow for a freezing stabilization of these spaces. In particular, we find for the R-1 model that configurations with stabilized extra dimensions do not provide a late-time acceleration (they are AdS), whereas the solution branch which allows for accelerated expansion (the dS branch) is incompatible with stabilized factor spaces. In the case of the R4 model, we obtain that the stability region in parameter space depends on the total dimension D = dim(M) of the higher dimensional spacetime M. For D > 8 the stability region consists of a single (absolutely stable) sector which is shielded from a conformal singularity (and an antigravity sector beyond it) by a potential barrier of infinite height and width. This sector is smoothly connected with the stability region of a curvature-linear model. For D < 8 an additional (metastable) sector exists which is separated from the conformal singularity by a potential barrier of finite height and width so that systems in this sector are prone to collapse into the conformal singularity. This second sector is not smoothly connected with the first (absolutely stable) one. Several limiting cases and the possibility of inflation are discussed for the R4 model.

Günther, Uwe; Zhuk, Alexander; Bezerra, Valdir B.; Romero, Carlos

2005-08-01

376

A NEW MULTI-DIMENSIONAL GENERAL RELATIVISTIC NEUTRINO HYDRODYNAMICS CODE FOR CORE-COLLAPSE SUPERNOVAE. II. RELATIVISTIC EXPLOSION MODELS OF CORE-COLLAPSE SUPERNOVAE  

SciTech Connect

We present the first two-dimensional general relativistic (GR) simulations of stellar core collapse and explosion with the COCONUT hydrodynamics code in combination with the VERTEX solver for energy-dependent, three-flavor neutrino transport, using the extended conformal flatness condition for approximating the space-time metric and a ray-by-ray-plus ansatz to tackle the multi-dimensionality of the transport. For both of the investigated 11.2 and 15 M{sub Sun} progenitors we obtain successful, though seemingly marginal, neutrino-driven supernova explosions. This outcome and the time evolution of the models basically agree with results previously obtained with the PROMETHEUS hydro solver including an approximative treatment of relativistic effects by a modified Newtonian potential. However, GR models exhibit subtle differences in the neutrinospheric conditions compared with Newtonian and pseudo-Newtonian simulations. These differences lead to significantly higher luminosities and mean energies of the radiated electron neutrinos and antineutrinos and therefore to larger energy-deposition rates and heating efficiencies in the gain layer with favorable consequences for strong nonradial mass motions and ultimately for an explosion. Moreover, energy transfer to the stellar medium around the neutrinospheres through nucleon recoil in scattering reactions of heavy-lepton neutrinos also enhances the mentioned effects. Together with previous pseudo-Newtonian models, the presented relativistic calculations suggest that the treatment of gravity and energy-exchanging neutrino interactions can make differences of even 50%-100% in some quantities and is likely to contribute to a finally successful explosion mechanism on no minor level than hydrodynamical differences between different dimensions.

Mueller, Bernhard; Janka, Hans-Thomas; Marek, Andreas, E-mail: bjmuellr@mpa-garching.mpg.de, E-mail: thj@mpa-garching.mpg.de [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)

2012-09-01

377

A New Multi-dimensional General Relativistic Neutrino Hydrodynamics Code for Core-collapse Supernovae. II. Relativistic Explosion Models of Core-collapse Supernovae  

NASA Astrophysics Data System (ADS)

We present the first two-dimensional general relativistic (GR) simulations of stellar core collapse and explosion with the COCONUT hydrodynamics code in combination with the VERTEX solver for energy-dependent, three-flavor neutrino transport, using the extended conformal flatness condition for approximating the space-time metric and a ray-by-ray-plus ansatz to tackle the multi-dimensionality of the transport. For both of the investigated 11.2 and 15 M ? progenitors we obtain successful, though seemingly marginal, neutrino-driven supernova explosions. This outcome and the time evolution of the models basically agree with results previously obtained with the PROMETHEUS hydro solver including an approximative treatment of relativistic effects by a modified Newtonian potential. However, GR models exhibit subtle differences in the neutrinospheric conditions compared with Newtonian and pseudo-Newtonian simulations. These differences lead to significantly higher luminosities and mean energies of the radiated electron neutrinos and antineutrinos and therefore to larger energy-deposition rates and heating efficiencies in the gain layer with favorable consequences for strong nonradial mass motions and ultimately for an explosion. Moreover, energy transfer to the stellar medium around the neutrinospheres through nucleon recoil in scattering reactions of heavy-lepton neutrinos also enhances the mentioned effects. Together with previous pseudo-Newtonian models, the presented relativistic calculations suggest that the treatment of gravity and energy-exchanging neutrino interactions can make differences of even 50%-100% in some quantities and is likely to contribute to a finally successful explosion mechanism on no minor level than hydrodynamical differences between different dimensions.

Müller, Bernhard; Janka, Hans-Thomas; Marek, Andreas

2012-09-01

378

POLARIZED LINE FORMATION IN MULTI-DIMENSIONAL MEDIA. IV. A FOURIER DECOMPOSITION TECHNIQUE TO FORMULATE THE TRANSFER EQUATION WITH ANGLE-DEPENDENT PARTIAL FREQUENCY REDISTRIBUTION  

SciTech Connect

To explain the linear polarization observed in spatially resolved structures in the solar atmosphere, the solution of polarized radiative transfer (RT) equation in multi-dimensional (multi-D) geometries is essential. For strong resonance lines, partial frequency redistribution (PRD) effects also become important. In a series of papers, we have been investigating the nature of Stokes profiles formed in multi-D media including PRD in line scattering. For numerical simplicity, so far we have restricted our attention to the particular case of PRD functions which are averaged over all the incident and scattered directions. In this paper, we formulate the polarized RT equation in multi-D media that takes into account the Hanle effect with angle-dependent PRD functions. We generalize here to the multi-D case the method for Fourier series expansion of angle-dependent PRD functions originally developed for RT in one-dimensional geometry. We show that the Stokes source vector S = (S{sub I} , S{sub Q} , S{sub U} ){sup T} and the Stokes vector I = (I, Q, U){sup T} can be expanded in terms of infinite sets of components S-tilde{sup (k)}, I-tilde{sup (k)}, respectively, k in [0, +{infinity}). We show that the components S-tilde{sup (k)} become independent of the azimuthal angle ({psi}) of the scattered ray, whereas the components I-tilde{sup (k)} remain dependent on {psi} due to the nature of RT in multi-D geometry. We also establish that S-tilde{sup (k)} and I-tilde{sup (k)} satisfy a simple transfer equation, which can be solved by any iterative method such as an approximate Lambda iteration or a Bi-Conjugate Gradient-type projection method provided we truncate the Fourier series to have a finite number of terms.

Anusha, L. S.; Nagendra, K. N. [Indian Institute of Astrophysics, Koramangala, 2nd Block, Bangalore 560 034 (India)

2011-09-20

379

Crack detection in beams in noisy conditions using scale fractal dimension analysis of mode shapes  

NASA Astrophysics Data System (ADS)

Fractal dimension analysis of mode shapes has been actively studied in the area of structural damage detection. The most prominent features of fractal dimension analysis are high sensitivity to damage and instant determination of damage location. However, an intrinsic deficiency is its susceptibility to measurement noise, likely obscuring the features of damage. To address this deficiency, this study develops a novel damage detection method, scale fractal dimension (SFD) analysis of mode shapes, based on combining the complementary merits of a stationary wavelet transform (SWT) and Katz’s fractal dimension in damage characterization. With this method, the SWT is used to decompose a mode shape into a set of scale mode shapes at scale levels, with damage information and noise separated into distinct scale mode shapes because of their dissimilar scale characteristics; the Katz’s fractal dimension individually runs on every scale mode shape in the noise-adaptive condition provided by the SWT to canvass damage. Proof of concept for the SFD analysis is performed on cracked beams simulated by the spectral finite element method; the reliability of the method is assessed using Monte Carlo simulation to mimic the operational variability in realistic damage diagnosis. The proposed method is further experimentally validated on a cracked aluminum beam with mode shapes acquired by a scanning laser vibrometer. The results show that the SFD analysis of mode shapes provides a new strategy for damage identification in noisy conditions.

Bai, R. B.; Ostachowicz, W.; Cao, M. S.; Su, Z.

2014-06-01

380

Enabling Continental-Scale Analysis of Vegetation Foliar Traits through Consistent Sampling and Analysis Protocols  

NASA Astrophysics Data System (ADS)

The National Ecological Observatory Network (NEON) is a continental-scale ecological observation platform designed to collect and disseminate data that contributes to understanding and forecasting the impacts of climate change, land use change, and invasive species on ecology. NEON will collect in-situ and airborne data over 60 sites across the US, including Alaska, Hawaii, and Puerto Rico. The NEON vegetation sampling protocol currently directs the collection of foliar samples from dominant species at each site; field spectra are collected from the samples that are further analyzed for bulk and isotopic carbon and nitrogen content. Through employment of consistent sampling and analysis strategies, NEON will provide a unique, rich, and varied data collection to support studies of foliar traits within species at specific sites and across/between regions. When combined with the NEON airborne hyperspectral and LiDAR imagery, these data will be key to support validation efforts of existing algorithms for deriving canopy scale nitrogen, carbon and other foliar traits, as well as supporting development of data products that are informed by - and include - the ground data specifically, thereby potentially reducing uncertainties in the observational data products. Presented here are prototype datasets collected at NEON Domain 1 (Harvard Forest, summer 2012) and Domain 17 (San Joaquin Experiment Range, summer 2013). Lessons-learned from the field campaigns are discussed, along with preliminary results from the Harvard Forest campaign, which combine the field and the laboratory data in support of current algorithm validation efforts. Extension of these protocols to future NEON Domain characterization activities is also presented.

Petroy, S. B.; Leisso, N.; Hinckley, E. S.; Meier, C. L.; Barnett, D.

2013-12-01

381

Automated Large-Scale Shoreline Variability Analysis From Video  

NASA Astrophysics Data System (ADS)

Land-based video has been used to quantify changes in nearshore conditions for over twenty years. By combining the ability to track rapid, short-term shoreline change and changes associated with longer term or seasonal processes, video has proved to be a cost effective and versatile tool for coastal science. Previous video-based studies of shoreline change have typically examined the position of the shoreline along a small number of cross-shore lines as a proxy for the continuous coast. The goal of this study is twofold: (1) to further develop automated shoreline extraction algorithms for continuous shorelines, and (2) to track the evolution of a nourishment project at Rehoboth Beach, DE that was concluded in June 2005. Seven cameras are situated approximately 30 meters above mean sea level and 70 meters from the shoreline. Time exposure and variance images are captured hourly during daylight and transferred to a local processing computer. After correcting for lens distortion and geo-rectifying to a shore-normal coordinate system, the images are merged to form a composite planform image of 6 km of coast. Automated extraction algorithms establish shoreline and breaker positions throughout a tidal cycle on a daily basis. Short and long term variability in the daily shoreline will be characterized using empirical orthogonal function (EOF) analysis. Periodic sediment volume information will be extracted by incorporating the results of monthly ground-based LIDAR surveys and by correlating the hourly shorelines to the corresponding tide level under conditions with minimal wave activity. The Delaware coast in the area downdrift of the nourishment site is intermittently interrupted by short groins. An Even/Odd analysis of the shoreline response around these groins will be performed. The impact of groins on the sediment volume transport along the coast during periods of accretive and erosive conditions will be discussed. [This work is being supported by DNREC and the Henlopen Hotel

Pearre, N. S.

2006-12-01

382

Bohr model and dimensional scaling analysis of atoms and molecules  

NASA Astrophysics Data System (ADS)

It is generally believed that the old quantum theory, as presented by Niels Bohr in 1913, fails when applied to many-electron systems, such as molecules, and nonhydrogenic atoms. It is the central theme of this dissertation to display with examples and applications the implementation of a simple and successful extension of Bohr's planetary model of the hydrogenic atom, which has recently been developed by an atomic and molecular theory group from Texas A&M University. This "extended" Bohr model, which can be derived from quantum mechanics using the well-known dimentional scaling technique is used to yield potential energy curves of H2 and several more complicated molecules, such as LiH, Li2, BeH, He2 and H3, with accuracies strikingly comparable to those obtained from the more lengthy and rigorous "ab initio" computations, and the added advantage that it provides a rather insightful and pictorial description of how electrons behave to form chemical bonds, a theme not central to "ab initio" quantum chemistry. Further investigation directed to CH, and the four-atom system H4 (with both linear and square configurations), via the interpolated Bohr model, and the constrained Bohr model (with an effective potential), respectively, is reported. The extended model is also used to calculate correlation energies. The model is readily applicable to the study of molecular species in the presence of strong magnetic fields, as is the case in the vicinities of white dwarfs and neutron stars. We find that magnetic field increases the binding energy and decreases the bond length. Finally, an elaborative review of doubly coupled quantum dots for a derivation of the electron exchange energy, a straightforward application of Heitler-London method of quantum molecular chemistry, concludes the dissertation. The highlights of the research are (1) a bridging together of the pre- and post quantum mechanical descriptions of the chemical bond (Bohr-Sommerfeld vs. Heisenberg-Schrodinger), and (2) the reporting of the appearance of new bound states of H2 in the presence of very strong magnetic fields. The new states emerge above the critical value of 5 x 107 G, and hence cannot be obtained perturbatively.

Urtekin, Kerim

383

Multifractal detrended fluctuation analysis in examining scaling properties of the spatial patterns of soil water storage  

NASA Astrophysics Data System (ADS)

Knowledge about the scaling properties of soil water storage is crucial in transferring locally measured fluctuations to larger scales and vice-versa. Studies based on remotely sensed data have shown that the variability in surface soil water has clear scaling properties (i.e., statistically self similar) over a wider range of spatial scales. However, the scaling property of soil water storage to a certain depth at a field scale is not well understood. The major challenges in scaling analysis for soil water are the presence of localized trends and nonstationarities in the spatial series. The objective of this study was to characterize scaling properties of soil water storage variability through multifractal detrended fluctuation analysis (MFDFA). A field experiment was conducted in a sub-humid climate at Alvena, Saskatchewan, Canada. A north-south transect of 624-m long was established on a rolling landscape. Soil water storage was monitored weekly between 2002 and 2005 at 104 locations along the transect. The spatial scaling property of the surface 0 to 40 cm depth was characterized using the MFDFA technique for six of the soil water content series (all gravimetrically determined) representing soil water storage after snowmelt, rainfall, and evapotranspiration. For the studied transect, scaling properties of soil water storage are different between drier periods and wet periods. It also appears that local controls such as site topography and texture (that dominantly control the pattern during wet states) results in multiscaling property. The nonlocal controls such as evapotranspiration results in the reduction of the degree of multiscaling and improvement in the simple scaling. Therefore, the scaling property of soil water storage is a function of both soil moisture status and the spatial extent considered.

Biswas, A.; Zeleke, T. B.; Si, B. C.

2012-03-01

384

Conceptual design and analysis of a dynamic scale model of the Space Station Freedom  

NASA Technical Reports Server (NTRS)

This report documents the conceptual design study performed to evaluate design options for a subscale dynamic test model which could be used to investigate the expected on-orbit structural dynamic characteristics of the Space Station Freedom early build configurations. The baseline option was a 'near-replica' model of the SSF SC-7 pre-integrated truss configuration. The approach used to develop conceptual design options involved three sets of studies: evaluation of the full-scale design and analysis databases, conducting scale factor trade studies, and performing design sensitivity studies. The scale factor trade study was conducted to develop a fundamental understanding of the key scaling parameters that drive design, performance and cost of a SSF dynamic scale model. Four scale model options were estimated: 1/4, 1/5, 1/7, and 1/10 scale. Prototype hardware was fabricated to assess producibility issues. Based on the results of the study, a 1/4-scale size is recommended based on the increased model fidelity associated with a larger scale factor. A design sensitivity study was performed to identify critical hardware component properties that drive dynamic performance. A total of 118 component properties were identified which require high-fidelity replication. Lower fidelity dynamic similarity scaling can be used for non-critical components.

Davis, D. A.; Gronet, M. J.; Tan, M. K.; Thorne, J.

1994-01-01

385

Stress analysis of 27% scale model of AH-64 main rotor hub  

NASA Technical Reports Server (NTRS)

Stress analysis of an AH-64 27% scale model rotor hub was performed. Component loads and stresses were calculated based upon blade root loads and motions. The static and fatigue analysis indicates positive margins of safety in all components checked. Using the format developed here, the hub can be stress checked for future application.

Hodges, R. V.

1985-01-01

386

A scanning AC calorimetry technique for the analysis of nano-scale quantities of materials  

E-print Network

A scanning AC calorimetry technique for the analysis of nano-scale quantities of materials Kechao OF SCIENTIFIC INSTRUMENTS 83, 114901 (2012) A scanning AC calorimetry technique for the analysis of nano 2012) We present a scanning AC nanocalorimetry method that enables calorimetry measurements at heating

387

Principal Component Analysis for Large Scale Problems with Lots of Missing Values  

Microsoft Academic Search

Principal component analysis (PCA) is a well-known classi- cal data analysis technique. There are a number of algorithms for solving the problem, some scaling better than others to problems with high di- mensionality. They also differ in their ability to handle missing values in the data. We study a case where the data are high-dimensional and a majority of the

Tapani Raiko; Alexander Ilin; Juha Karhunen

2007-01-01

388

Construct Validation of the Child Sex Abuse Attitude Scale (CSAAS) through Confirmatory Factor Analysis.  

ERIC Educational Resources Information Center

A validation study was conducted on the Child Sex Abuse Attitude Scale (CSAAS) using confirmatory factor analysis (CFA) to examine the factor structure of three comparative CFA models. Multitrait multimethod analysis was also used to examine the convergent and discriminant validity of the CSAAS. The instrument was developed based on the theory of…

Ferrara, Filomena Felicia

389

Homogeneity Analysis with "k" Sets of Variables: An Alternating Least Squares Method with Optimal Scaling Features.  

ERIC Educational Resources Information Center

Homogeneity analysis (multiple correspondence analysis), which is usually applied to "k" separate variables, was applied to sets of variables by using sums within sets. The resulting technique, OVERALS, uses optimal scaling. The corresponding OVERALS computer program minimizes a least squares loss function via an alternating least squares…

van der Burg, Eeke; de Leeuw, Jan

1988-01-01

390

MULTI-SCALE ANALYSIS OF WATER ALTERATION ON THE ROCKSLOPE STABILITY FRAMEWORK  

E-print Network

on the rock slope stability analysis. The aim of this paper is the multi scale analysis of the chemical impact and will be presented. KEY WORDS: Water, chemical degradation, rock discontinuity, stability. 1 INTRODUCTION Roads-Polish Colloquium of Soil and Rock Mechanics, Montpellier : France (2013)" #12;2 In addition of chemical reactions

Paris-Sud XI, Université de

391

Using Profile Analysis via Multidimensional Scaling (PAMS) to Identify Core Profiles from the WMS-III  

ERIC Educational Resources Information Center

Profile Analysis via Multidimensional Scaling (PAMS) is a procedure for extracting latent core profiles in a multitest data set. The PAMS procedure offers several advantages compared with other profile analysis procedures. Most notably, PAMS estimates individual profile weights that reflect the degree to which an individual's observed profile…

Frisby, Craig L.; Kim, Se-Kang

2008-01-01

392

An analysis of space scales for sea ice drift  

SciTech Connect

Sea ice presents a hazard to navigation off Canada`s east coast from January to June. The Ice Centre Environment Canada (ICEC) which is part of the Atmospheric Environment Service monitors ice conditions in order to assist safe and efficient operations through or around the ice. The ice program depends on an advanced data acquisition, analysis and forecasting effort. Support for the latter is provided by kinematic models as well as a fairly simple dynamic sea ice model. In order to improve ICEC`s forecasting capabilities, the Department of Fisheries and Oceans (DFO) conducts ice modelling research and regular field experiments. The experiments provide a better understanding of the ice and also allow models to be validated and refined. The Bedford Institute of Oceanography (BIO, part of DFO) regularly deploys beacons on ice floes off the Labrador and Newfoundland coasts. These beacons provide environmental as well as location information through Service ARGOS. Documentation on the accuracy and information of the sensors is documented in Prinsenberg, 1993. The beacon locations are used here to infer an relatively unbiased representation of sea ice drift.

Carrieres, T. [Ice Centre Environment Canada, Ottawa, Ontario (Canada)

1994-12-31

393

Brazilian version of the Jefferson Scale of Empathy: psychometric properties and factor analysis  

PubMed Central

Background Empathy is a central characteristic of medical professionalism and has recently gained attention in medical education research. The Jefferson Scale of Empathy is the most commonly used measure of empathy worldwide, and to date it has been translated in 39 languages. This study aimed to adapt the Jefferson Scale of Empathy to the Brazilian culture and to test its reliability and validity among Brazilian medical students. Methods The Portuguese version of the Jefferson Scale of Empathy was adapted to Brazil using back-translation techniques. This version was pretested among 39 fifth-year medical students in September 2010. During the final fifth- and sixth-year Objective Structured Clinical Examination (October 2011), 319 students were invited to respond to the scale anonymously. Cronbach’s alpha, exploratory factor analysis, item-total correlation, and gender comparisons were performed to check the reliability and validity of the scale. Results The student response rate was 93.7% (299 students). Cronbach’s coefficient for the scale was 0.84. A principal component analysis confirmed the construct validity of the scale for three main factors: Compassionate Care (first factor), Ability to Stand in the Patient’s Shoes (second factor), and Perspective Taking (third factor). Gender comparisons did not reveal differences in the scores between female and male students. Conclusions The adapted Brazilian version of the Jefferson Scale of Empathy proved to be a valid, reliable instrument for use in national and cross-cultural studies in medical education. PMID:22873730

2012-01-01

394

Scaling Analysis for the Direct Reactor Auxiliary Cooling System for AHTRs  

SciTech Connect

The Direct Reactor Auxiliary Cooling System (DRACS), shown in Fig. 1 [1], is a passive heat removal system proposed for the Advanced High-Temperature Reactor (AHTR). It features three coupled natural circulation/convection loops completely relying on the buoyancy as the driving force. A prototypic design of the DRACS employed in a 20-MWth AHTR has been discussed in our previous work [2]. The total height of the DRACS is usually more than 10 m, and the required heating power will be large (on the order of 200 kW), both of which make a full-scale experiment not feasible in our laboratory. This therefore motivates us to perform a scaling analysis for the DRACS to obtain a scaled-down model. In this paper, theory and methodology for such a scaling analysis are presented.

Yoder Jr, Graydon L [ORNL] [ORNL; Wilson, Dane F [ORNL] [ORNL; Wang, X. NMN [Ohio State University] [Ohio State University; Lv, Q. NMN [Ohio State University] [Ohio State University; Sun, X NMN [Ohio State University] [Ohio State University; Christensen, R. N. [Ohio State University] [Ohio State University; Blue, T. E. [Ohio State University] [Ohio State University; Subharwall, Piyush [Idaho National Laboratory (INL)] [Idaho National Laboratory (INL)

2011-01-01

395

Scaling analysis applied to the NORVEX code development and thermal energy flight experiment  

NASA Technical Reports Server (NTRS)

A scaling analysis is used to study the dominant flow processes that occur in molten phase change material (PCM) under 1 g and microgravity conditions. Results of the scaling analysis are applied to the development of the NORVEX (NASA Oak Ridge Void Experiment) computer program and the preparation of the Thermal Energy Storage (TES) flight experiment. The NORVEX computer program which is being developed to predict melting and freezing with void formation in a 1 g or microgravity environment of the PCM is described. NORVEX predictions are compared with the scaling and similarity results. The approach to be used to validate NORVEX with TES flight data is also discussed. Similarity and scaling show that the inertial terms must be included as part of the momentum equation in either the 1 g or microgravity environment (a creeping flow assumption is invalid). A 10(exp -4) environment was found to be a suitable microgravity environment for the proposed PCM.

Skarda, J. Raymond Lee; Namkoong, David; Darling, Douglas

1991-01-01

396

Spatial scaling: Its analysis and effects on animal movements in semiarid landscape mosaics  

SciTech Connect

The research conducted under this agreement focused in general on the effects of envirorunental heterogeneity on movements of animals and materials in semiarid grassland landscapes, on the form of scale-dependency of ecological patterns and processes, and on approaches to extrapolating among spatial scales. The findings are summarized in a series of published and unpublished papers that are included as the main body of this report. We demonstrated the value of experimental model systems'' employing observations and experiments conducted in small-scale microlandscapes to test concepts relating to flows of individuals and materials through complex, heterogeneous mosaics. We used fractal analysis extensively in this research, and showed how fractal measures can produce insights and lead,to questions that do not emerge from more traditional scale-dependent measures. We developed new concepts and theory to deal with scale-dependency in ecological systems and with integrating individual movement patterns into considerations of population and ecosystem dynamics.

Wiens, J.A.

1992-09-01

397

Persian adaptation of Foreign Language Reading Anxiety Scale: a psychometric analysis.  

PubMed

The validity and psychometric properties of a new Persian adaptation of the Foreign Language Reading Anxiety Scale were investigated. The scale was translated into Persian and administered to 160 undergraduate students (131 women, 29 men; M age = 23.4 yr., SD = 4.3). Rasch model analysis on the scale's original 20 items revealed that the data do not fit the partial credit model. Principal components analysis identified three factors: one related to feelings of anxiety about reading, the second reflected the reverse-worded items, and the third related to general ideas about reading in a foreign language. In a re-analysis, the 12 items that loaded on the first factor showed a good fit with the partial credit model. PMID:24897892

Baghaei, Purya; Hohensinn, Christine; Kubinger, Klaus D

2014-04-01

398

A new approach for modeling and analysis of molten salt reactors using SCALE  

SciTech Connect

The Office of Fuel Cycle Technologies (FCT) of the DOE Office of Nuclear Energy is performing an evaluation and screening of potential fuel cycle options to provide information that can support future research and development decisions based on the more promising fuel cycle options. [1] A comprehensive set of fuel cycle options are put into evaluation groups based on physics and fuel cycle characteristics. Representative options for each group are then evaluated to provide the quantitative information needed to support the valuation of criteria and metrics used for the study. Included in this set of representative options are Molten Salt Reactors (MSRs), the analysis of which requires several capabilities that are not adequately supported by the current version of SCALE or other neutronics depletion software packages (e.g., continuous online feed and removal of materials). A new analysis approach was developed for MSR analysis using SCALE by taking user-specified MSR parameters and performing a series of SCALE/TRITON calculations to determine the resulting equilibrium operating conditions. This paper provides a detailed description of the new analysis approach, including the modeling equations and radiation transport models used. Results for an MSR fuel cycle option of interest are also provided to demonstrate the application to a relevant problem. The current implementation is through a utility code that uses the two-dimensional (2D) TRITON depletion sequence in SCALE 6.1 but could be readily adapted to three-dimensional (3D) TRITON depletion sequences or other versions of SCALE. (authors)

Powers, J. J.; Harrison, T. J.; Gehin, J. C. [Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6172 (United States)

2013-07-01

399

Application of bioreactor design principles and multivariate analysis for development of cell culture scale down models.  

PubMed

A bench scale cell culture model representative of manufacturing scale (2,000?L) was developed based on oxygen mass transfer principles, for a CHO-based process producing a recombinant human protein. Cell culture performance differences across scales are characterized most often by sub-optimal performance in manufacturing scale bioreactors. By contrast in this study, reduced growth rates were observed at bench scale during the initial model development. Bioreactor models based on power per unit volume (P/V), volumetric mass transfer coefficient (kL a), and oxygen transfer rate (OTR) were evaluated to address this scale performance difference. Lower viable cell densities observed for the P/V model were attributed to higher sparge rates and reduced oxygen mass transfer efficiency (kL a) of the small scale hole spargers. Increasing the sparger kL a by decreasing the pore size resulted in a further decrease in growth at bench scale. Due to sensitivity of the cell line to gas sparge rate and bubble size that was revealed by the P/V and kL a models, an OTR model based on oxygen enrichment and increased P/V was selected that generated endpoint sparge rates representative of 2,000?L scale. This final bench scale model generated similar growth rates as manufacturing. In order to take into account other routinely monitored process parameters besides growth, a multivariate statistical approach was applied to demonstrate validity of the small scale model. After the model was selected based on univariate and multivariate analysis, product quality was generated and verified to fall within the 95% confidence limit of the multivariate model. Biotechnol. Bioeng. 2015;112: 84-97. © 2014 Wiley Periodicals, Inc. PMID:25042258

Tescione, Lia; Lambropoulos, James; Paranandi, Madhava Ram; Makagiansar, Helena; Ryll, Thomas

2015-01-01

400

Scaling behavior of high resolution temporal rainfall: New insights from a wavelet-based cumulant analysis  

NASA Astrophysics Data System (ADS)

We revisit the multifractal analysis of high resolution temporal rainfall using the wavelet transform modulus maxima (WTMM) method. Specifically, we employ a cumulant analysis of the logarithm of the WTMM coefficients to estimate the scaling exponent spectrum ?(q) and the spectrum of singularities D(h). We document that rainfall intensity fluctuations exhibit multifractality from scales of the order of 4 5 minutes up to the storm-pulse duration of 1 2 hours. We also establish long-range dependence consistent with that of a multiplicative cascade.

Venugopal, V.; Roux, Stéphane G.; Foufoula-Georgiou, Efi; Arnéodo, Alain

2006-01-01

401

Multi-scale analysis of the spatial variability of soil organic carbon  

NASA Astrophysics Data System (ADS)

Information on soil properties and state is required for food security, global environmental management and climate change mitigation. Therefore, important efforts are put in the collection of soil data of many types and at very different spatial scales. Besides, soil organic carbon dynamics models at regional or global level and integrated soil policies require to predict soil properties on extensive areas, while keeping a resolution of a few meters. However, predict soil properties at fine resolution on large area is challenging, since soil properties are generally the result of a large number of soil processes, which may act at very different spatial scale. Indeed, both the strength and the nature of the link between soil properties and environmental factors depend on the scale at which we look to. Therefore, the characterization of the link between a soil property and a given controlling factor may be complicated by some variability in the soil property resulting from additionnal processes acting at other spatial scales. We propose a method of geostatistical analysis to decompose the spatial information on a soil property into multiple scale components. The variogram of soil properties is modeled by a function which is the sum of multiple sub-model with different ranges. Each sub-model can be used separately to predict the soil property at a particular scale. The analysis was performed in Belgian Loess Belt with the legacy dataset Aardewerk. The method allowed to highlight relationships between soil properties at particular spatial scales, which were hardly observable without spatial decomposition. In particular, the link between texture and organic carbon, or between topsoil and subsoil organic carbon, appeared more clearly at the coarsest scale. Besides allowing a better understanding of the controls on soil variables, the method provides a way to improve prediction of soil variables when different covariates are available at different scales.

Stevens, François; Bogaert, Patrick; van Wesemael, Bas

2014-05-01

402

Confirmatory Factor Analysis of Combined Wechsler Adult Intelligence Scale—Revised and Wechsler Memory Scale—Revised Scores in a Healthy Community Sample  

Microsoft Academic Search

This study examined the joint factor structure of the Wechsler Adult Intelligence Scale—Revised (D. Wechsler, 1981) and Wechsler Memory Scale—Revised (D. Wechsler, 1987) in a sample of 399 healthy young adults (206 women and 193 men) recruited for a normative study in Sydney, Australia: the Macquarie University Neuropsychological Normative Study. Using confirmatory factor analysis, the authors contrasted alternative models of

Stephen C. Bowden; Jane R. Carstairs; E. Arthur Shores

1999-01-01

403

Manipulating measurement scales in medical statistical analysis and data mining: A review of methodologies  

PubMed Central

Background: selecting the correct statistical test and data mining method depends highly on the measurement scale of data, type of variables, and purpose of the analysis. Different measurement scales are studied in details and statistical comparison, modeling, and data mining methods are studied based upon using several medical examples. We have presented two ordinal–variables clustering examples, as more challenging variable in analysis, using Wisconsin Breast Cancer Data (WBCD). Ordinal-to-Interval scale conversion example: a breast cancer database of nine 10-level ordinal variables for 683 patients was analyzed by two ordinal-scale clustering methods. The performance of the clustering methods was assessed by comparison with the gold standard groups of malignant and benign cases that had been identified by clinical tests. Results: the sensitivity and accuracy of the two clustering methods were 98% and 96%, respectively. Their specificity was comparable. Conclusion: by using appropriate clustering algorithm based on the measurement scale of the variables in the study, high performance is granted. Moreover, descriptive and inferential statistics in addition to modeling approach must be selected based on the scale of the variables. PMID:24672565

Marateb, Hamid Reza; Mansourian, Marjan; Adibi, Peyman; Farina, Dario

2014-01-01

404

Comparative water use of native and invasive plants at multiple scales: a global meta-analysis.  

PubMed

Ecohydrology and invasive ecology have become increasingly important in the context of global climate change. This study presents the first in-depth analysis of the water use of invasive and native plants of the same growth form at multiple scales: leaf, plant, and ecosystem. We reanalyzed data for several hundred native and invasive species from over 40 published studies worldwide to glean global trends and to highlight how patterns vary depending on both scale and climate. We analyzed all pairwise combinations of co-occurring native and invasive species for higher comparative resolution of the likelihood of an invasive species using more water than a native species and tested for significance using bootstrap methods. At each scale, we found several-fold differences in water use between specific paired invasive and native species. At the leaf scale, we found a strong tendency for invasive species to have greater stomatal conductance than native species. At the plant scale, however, natives and invasives were equally likely to have the higher sap flow rates. Available data were much fewer for the ecosystem scale; nevertheless, we found that invasive-dominated ecosystems were more likely to have higher sap flow rates per unit ground area than native-dominated ecosystems. Ecosystem-scale evapotranspiration, on the other hand, was equally likely to be greater for systems dominated by invasive and native species of the same growth form. The inherent disconnects in the determination of water use when changing scales from leaf to plant to ecosystem reveal hypotheses for future studies and a critical need for more ecosystem-scale water use measurements in invasive- vs. native-dominated systems. The differences in water use of native and invasive species also depended strongly on climate, with the greater water use of invasives enhanced in hotter, wetter climates at the coarser scales. PMID:20957964

Cavaleri, Molly A; Sack, Lawren

2010-09-01

405

INTERMON Complex QoS\\/SLA analysis in large scale Internet environment  

Microsoft Academic Search

An advanced architecture for inter-domain QoS analysis, developed in the framework of European IST Project INTERMON1, for automation of tasks in the area of inter-domain QoS\\/SLA monitoring, connectivity planning and traffic engineering is presented. The main focus of the INTERMON toolkit is the integration of tools covering different aspects of QoS analysis in large scale Internet environment such as inter-domain

U. Hofmann; T. Pfeiffenberger

406

Multi-scale Analysis of MEMS Sensors Subject to Drop Impacts  

PubMed Central

The effect of accidental drops on MEMS sensors are examined within the framework of a multi-scale finite element approach. With specific reference to a polysilicon MEMS accelerometer supported by a naked die, the analysis is decoupled into macro-scale (at die length-scale) and meso-scale (at MEMS length-scale) simulations, accounting for the very small inertial contribution of the sensor to the overall dynamics of the device. Macro-scale analyses are adopted to get insights into the link between shock waves caused by the impact against a target surface and propagating inside the die, and the displacement/acceleration histories at the MEMS anchor points. Meso-scale analyses are adopted to detect the most stressed details of the sensor and to assess whether the impact can lead to possible localized failures. Numerical results show that the acceleration at sensor anchors cannot be considered an objective indicator for drop severity. Instead, accurate analyses at sensor level are necessary to establish how MEMS can fail because of drops.

Mariani, Stefano; Ghisi, Aldo; Corigliano, Alberto; Zerbini, Sarah

2007-01-01

407

Wavelet based directional analysis of the gravity field: evidence for large-scale undulation  

NASA Astrophysics Data System (ADS)

Since the advent of satellite altimetry and the new view it provided on marine gravity in the eighties, the existence and origin of undulated pattern in the gravity field over the oceans is a matter of debate. While it is agreed upon the existence and locations of small scale undulations, the existence and characteristics of larger scale undulations are less clear. Here, we readdress this question, in the light of the recent data from the GRACE mission, that reach an unprecedented precision at large spatial scales. For that, we developed and applied new analysis techniques using directional spherical Poisson wavelets. Our results demonstrate the existence of gravity undulations of large scales in the oceans, with characteristic scales between 600 and 2000 km, that may even have a global nature. They are particularly clear in the Pacific ocean, where we discovered a superposition of lineated patterns, the dominant one at a scale around 2000 km, being roughly parallel to the plate motion direction. We also observe undulations in a conjugate direction (NE-SW) at about 1500 km scale. We hypothetize that these undulations indicate a directional structure of the deep mantle upwellings, related to the impact of the past and present subductions on the organization of mantle flows.

Hayn, M.; Panet, I.; Diament, M.; Holschneider, M.; Mandea, M.; Davaille, A. B.

2012-12-01

408

Wavelet-based multifractal analysis of field scale variability in soil water retention  

NASA Astrophysics Data System (ADS)

Better understanding of spatial variability of soil hydraulic parameters and their relationships to other soil properties is essential to scale-up measured hydraulic parameters and to improve the predictive capacity of pedotransfer functions. The objective of this study was to characterize scaling properties and the persistency of water retention parameters and soil physical properties. Soil texture, bulk density, organic carbon content, and the parameters of the van Genuchten water retention function were determined on 128 soil cores from a 384-m transect with a sandy loam soil, located at Smeaton, SK, Canada. The wavelet transform modulus maxima, or WTMM, technique was used in the multifractal analysis. Results indicate that the fitted water retention parameters had higher small-scale variability and lower persistency than the measured soil physical properties. Of the three distinct scaling ranges identified, the middle region (8-128 m) had a multifractal-type scaling. The generalized Hurst exponent indicated that the measured soil properties were more persistent than the fitted soil hydraulic parameters. The relationships observed here imply that soil physical properties are better predictors of water retention values at larger spatial scales than at smaller scales.

Zeleke, Takele B.; Si, Bing C.

2007-07-01

409

Multi-scale dynamical analysis (MSDA) of sea level records versus PDO, AMO, and NAO indexes  

E-print Network

Herein I propose a multi-scale dynamical analysis to facilitate the physical interpretation of tide gauge records. The technique uses graphical diagrams. It is applied to six secular-long tide gauge records representative of the world oceans: Sydney, Pacific coast of Australia; Fremantle, Indian Ocean coast of Australia; New York City, Atlantic coast of USA; Honolulu, U.S. state of Hawaii; San Diego, U.S. state of California; and Venice, Mediterranean Sea, Italy. For comparison, an equivalent analysis is applied to the Pacific Decadal Oscillation (PDO) index and to the Atlantic Multidecadal Oscillation (AMO) index. Finally, a global reconstruction of sea level and a reconstruction of the North Atlantic Oscillation (NAO) index are analyzed and compared: both sequences cover about three centuries from 1700 to 2000. The proposed methodology quickly highlights oscillations and teleconnections among the records at the decadal and multidecadal scales. At the secular time scales tide gauge records present relatively...

Scafetta, Nicola

2013-01-01

410

COMPARATIVE ANALYSIS OF SRAM CELL DESIGNS IN NANO-SCALE A dissertation submitted to the faculty of  

E-print Network

COMPARATIVE ANALYSIS OF SRAM CELL DESIGNS IN NANO-SCALE TECHNOLOGY A dissertation submitted certify that I have read Comparative Analysis of SRAM Cell Designs in Nano-Scale Technology by Shreyas __________________________________________________ Hao Jiang Assistant Professor, Electrical and Computer Engineering #12;COMPARATIVE ANALYSIS OF SRAM

Mahmoodi, Hamid

411

Module-scale analysis of pressure retarded osmosis: performance limitations and implications for full-scale operation.  

PubMed

We investigate the performance of pressure retarded osmosis (PRO) at the module scale, accounting for the detrimental effects of reverse salt flux, internal concentration polarization, and external concentration polarization. Our analysis offers insights on optimization of three critical operation and design parameters-applied hydraulic pressure, initial feed flow rate fraction, and membrane area-to maximize the specific energy and power density extractable in the system. For co- and counter-current flow modules, we determine that appropriate selection of the membrane area is critical to obtain a high specific energy. Furthermore, we find that the optimal operating conditions in a realistic module can be reasonably approximated using established optima for an ideal system (i.e., an applied hydraulic pressure equal to approximately half the osmotic pressure difference and an initial feed flow rate fraction that provides equal amounts of feed and draw solutions). For a system in counter-current operation with a river water (0.015 M NaCl) and seawater (0.6 M NaCl) solution pairing, the maximum specific energy obtainable using performance properties of commercially available membranes was determined to be 0.147 kWh per m(3) of total mixed solution, which is 57% of the Gibbs free energy of mixing. Operating to obtain a high specific energy, however, results in very low power densities (less than 2 W/m(2)), indicating that the trade-off between power density and specific energy is an inherent challenge to full-scale PRO systems. Finally, we quantify additional losses and energetic costs in the PRO system, which further reduce the net specific energy and indicate serious challenges in extracting net energy in PRO with river water and seawater solution pairings. PMID:25222561

Straub, Anthony P; Lin, Shihong; Elimelech, Menachem

2014-10-21

412

Modelling Pesticide Leaching At Column, Field and Catchment Scales I. Analysis of Soil Variability At Field and Catchment Scales  

NASA Astrophysics Data System (ADS)

The spatial variability of soil characteristics was studied in a small agricultural catch- ment (Vemmenhög, 9 km2) at the field and catchment scales. This analysis serves as a basis for assumptions concerning upscaling approaches used to model pesticide leaching from the catchment with the MACRO model (Jarvis et al., this meeting). The work focused on the spatial variability of two key soil properties for pesticide fate in soil, organic carbon and clay content. The Vemmenhög catchment (9 km2) is formed in a glacial till deposit in southernmost Sweden. The landscape is undulating (30 - 65 m a.s.l.) and 95 % of the area is used for crop production (winter rape, winter wheat, sugar beet and spring barley). The climate is warm temperate. Soil samples for or- ganic C and texture were taken on a small regular grid at Näsby Farm, (144 m x 144 m, sampling distance: 6-24 m, 77 points) and on an irregular large grid covering the whole catchment (sampling distance: 333 m, 46 points). At the field scale, it could be shown that the organic C content was strongly related to landscape position and height (R2= 73 %, p < 0.001, n=50). The organic C content of hollows in the landscape is so high that they contribute little to the total loss of pesticides (Jarvis et al., this meeting). Clay content is also related to landscape position, being larger at the hilltop locations resulting in lower near-saturated hydraulic conductivity. Hence, macropore flow can be expected to be more pronounced (see also Roulier & Jarvis, this meeting). The variability in organic C was similar for the field and catchment grids, which made it possible to krige the organic C content of the whole catchment using data from both grids and an uneven lag distance.

Gärdenäs, A.; Jarvis, N.; Alavi, G.

413

A new Analysis of Intermittence, Scale Invariance and Characteristic Scales applied to the Behavior of Financial Indices near a Crash  

E-print Network

years the study of log-periodic structures and characteristic scales and the relation with the concept of scale invariance had grown due to the great amount of physical systems presenting log-periodic

Mariani, Maria Christina

414

Data Mining: Data Analysis on a Grand Scale? \\Lambda Padhraic Smyth  

E-print Network

Data Mining: Data Analysis on a Grand Scale? \\Lambda Padhraic Smyth Information and Computer data mining has evolved largely as a result of efforts by computer scientists to address the needs of ``data owners'' in extracting useful information from massive observational data sets. Because

Smyth, Padhraic

415

Scales of environmental justice: Combining GIS and spatial analysis for air toxics in West Oakland, California  

Microsoft Academic Search

This paper examines the spatial point pattern of industrial toxic substances and the associated environmental justice implications in the San Francisco Bay Area, California, USA. Using a spatial analysis method called Ripley's K we assess environmental justice across multiple spatial scales, and we verify and quantify the West Oakland neighborhood as an environmental justice site as designated by the US

Joshua B. Fisher; Maggi Kelly; Jeff Romm

2006-01-01

416

Listening Factors: A Large-Scale Principal Components Analysis of Long-Term Music Listening Histories  

E-print Network

such as concerts and the current mood all play a role for choosing music. This means that it is hard to judge whatListening Factors: A Large-Scale Principal Components Analysis of Long-Term Music Listening.butz@ifi.lmu.de ABSTRACT There are about as many strategies for listening to music as there are music enthusiasts

417

Multi-modal Analysis of Music: A large-scale Evaluation  

E-print Network

- modality of music, with most research studies focusing on lyrics for e.g. emotion, mood or topic detectionMulti-modal Analysis of Music: A large-scale Evaluation Rudolf Mayer Institute of Software different types of content modalities. Music specifically inherits e.g. audio at its core, text in the form

418

Taxometric Analysis of the Antisocial Features Scale of the Personality Assessment Inventory in Federal Prison Inmates  

ERIC Educational Resources Information Center

The Antisocial Features (ANT) scale of the Personality Assessment Inventory (PAI) was subjected to taxometric analysis in a group of 2,135 federal prison inmates. Scores on the three ANT subscales--Antisocial Behaviors (ANT-A), Egocentricity (ANT-E), and Stimulus Seeking (ANT-S)--served as indicators in this study and were evaluated using the…

Walters, Glenn D.; Diamond, Pamela M.; Magaletta, Philip R.; Geyer, Matthew D.; Duncan, Scott A.

2007-01-01

419

Maggie's Day: A Small-Scale Analysis of English Education Policy  

ERIC Educational Resources Information Center

Policy sociologists typically research at large scale. This paper presents an example of a policy analysis which illuminates how policy is embedded in single incidents, lives and places. The case in point concerns the policy fetish for "closing the gap and raising the bar". This rhetoric is taken to mean improving the learning of all students,…

Thomson, Pat; Hall, Christine; Jones, Ken

2010-01-01

420

BLOWING BUBBLES FOR THE MULTI-SCALE ANALYSIS AND DECOMPOSITION OF TRIANGLE-MESHES  

E-print Network

1 BLOWING BUBBLES FOR THE MULTI-SCALE ANALYSIS AND DECOMPOSITION OF TRIANGLE-MESHES M. MORTARA is based on blowing a spherical bubble at each vertex and studying how the intersection of that bubble of bubble radii and for using them to identify features, based on easily formulated filters, that may

Rossignac, Jarek

421

Analysis of Heating Systems and Scale of Natural Gas-Condensing Water Boilers in Northern Zones  

E-print Network

In this paper, various heating systems and scale of the natural gas-condensing water boiler in northern zones are discussed, based on a technical-economic analysis of the heating systems of natural gas condensing water boilers in northern zones...

Wu, Y.; Wang, S.; Pan, S.; Shi, Y.

2006-01-01

422

A Principal Components Analysis and Validation of the Coping with the College Environment Scale (CWCES)  

ERIC Educational Resources Information Center

The present study describes the development and initial validation of the Coping with the College Environment Scale (CWCES). Participants included 433 college students who took an online survey. Principal Components Analysis (PCA) revealed six coping strategies: planning and self-management, seeking support from institutional resources, escaping…

Ackermann, Margot Elise; Morrow, Jennifer Ann

2008-01-01

423

Factor analysis of responses to the Irrational Beliefs Scale in a sample of Iraqi university students.  

PubMed

In a study of irrational beliefs within a university population, 282 male and 238 female students responded to the 33-item Students' Irrational Beliefs Scale, and their responses were factor analyzed. Analysis suggested six dimensions could explain 39.5% of the variance. These dimensions were Perfectionism, Negativism, Blame Proneness, Escapism, Anxious Over Concern, and Absolute Demands. PMID:15217026

Hassan, Namir; Ismail, Hairul Nizam

2004-06-01

424

Multiple Peak Alignment in Sequential Data Analysis: A Scale-Space-Based Approach  

Microsoft Academic Search

In this paper, we address the multiple peak alignment problem in sequential data analysis with an approach based on the Gaussian scale-space theory. We assume that multiple sets of detected peaks are the observed samples of a set of common peaks. We also assume that the locations of the observed peaks follow unimodal distributions (e.g., normal distribution) with their means

Weichuan Yu; Xiaoye Li; Junfeng Liu; Baolin Wu; Kenneth R. Williams; Hongyu Zhao

2006-01-01

425

MARVIN: A platform for large-scale analysis of Semantic Web data  

E-print Network

interlinked exports of the "deep Web", which has traditionally been hard to obtain and analyse [14]. However1 MARVIN: A platform for large-scale analysis of Semantic Web data Eyal Oren, Spyros Kotoulas, Vrije Universiteit Amsterdam, the Netherlands Abstract--Web Science requires efficient techniques

ten Teije, Annette

426

Scale Economies in Academic Excellence: An Exploratory Analysis of the United Kingdom's 1992 Research Selectivity Exercise.  

ERIC Educational Resources Information Center

Results of a 1992 British assessment of university departments are analyzed, particularly the finding that in general, larger departments were given higher research ratings. Analysis suggests an "economies of scale" effect and components of performance attributable to either "size" or "non-size" are identified. Implications are drawn for academic…

Hoare, Anthony G.

1995-01-01

427

The Columbia Impairment Scale: Factor Analysis Using a Community Mental Health Sample  

ERIC Educational Resources Information Center

Objective: The objective of this study was to test the factor structure of the parent version of the Columbia Impairment Scale (CIS) in a sample of mothers who brought their children for community mental health (CMH) services (n = 280). Method: Confirmatory factor analysis (CFA) was used to test the fit of the hypothesized four-factor structure…

Singer, Jonathan B.; Eack, Shaun M.; Greeno, Catherine M.

2011-01-01

428

The Nurturant Fathering Scale: A Confirmatory Factor Analysis with an African American Sample of College Students  

ERIC Educational Resources Information Center

Objective: The objective of this study was to test the factor structure of the "Nurturant Fathering Scale" (NFS) among an African American sample in the mid-Atlantic region that have neither Caribbean heritage nor immigration experiences but who do have diverse family structures (N = 212). Method: A confirmatory factor analysis (CFA) was conducted…

Doyle, Otima; Pecukonis, Edward; Harrington, Donna

2011-01-01

429

Confirmatory analysis of the factorial structure and validity of the service provider sociality scale  

Microsoft Academic Search

This investigation assessed the factorial structure and validity of the Service Provider Sociality Scale (SPSS). The SPSS was administered to 455 customers, including 255 undergraduate students attending a small Midwestern college and 200 residents in communities surrounding the college. Confirmatory factor analysis results indicated that the service provider sociality measurement model had significant composite reliability and discriminant validity. Implications and

Chas D. Koermer; Mary C. Toale; Wendy S. Zabava Ford; Andy D. Dohanos

2003-01-01

430

The Neale Scales of Early Childhood Development and Later Reading Performance: A Multivariate Analysis.  

ERIC Educational Resources Information Center

A multivariate analysis of variance, using three factors obtained from a preschool developmental index (Neale Scales) as the dependent variables, and group membership based on subsequent longitudinal reading performance as the independent variables, resulted in a significant multivariate F for a sample of 204 kindergarten children. (Author/SBH)

Neale, Marie D.; And Others

1979-01-01

431

Mobility analysis, simulation, and scale model testing for the design of wheeled planetary rovers  

Microsoft Academic Search

The use of computer based techniques to model and simulate wheeled rovers on rough natural terrains is considered. Physical models of a prototype vehicle can be used to test the correlation of the simulations in scaled testing. The computer approaches include a quasi-static planar or two dimensional analysis and design tool based on the traction necessary for the vehicle to

Randel A. Lindemann; Howard J. Eisen

1993-01-01

432

LARGE SCALE DISASTER ANALYSIS AND MANAGEMENT: SYSTEM LEVEL STUDY ON AN INTEGRATED MODEL  

EPA Science Inventory

The increasing intensity and scale of human activity across the globe leading to severe depletion and deterioration of the Earth's natural resources has meant that sustainability has emerged as a new paradigm of analysis and management. Sustainability, conceptually defined by the...

433

Selective harvesting by small-scale sheries: ecosystem analysis of San Miguel Bay, Philippines  

E-print Network

Selective harvesting by small-scale ®sheries: ecosystem analysis of San Miguel Bay, Philippines September 2000 Abstract San Miguel Bay is a large embayment along the Paci®c coast of southeast Luzon, Philippines. The estuarine ecosystem therein is described through a mass-balance model that includes 16

Pauly, Daniel

434

Analysis of Thermoelectric Properties of Scaled Silicon Nanowires Using an Atomistic Tight-Binding Model  

E-print Network

1 Analysis of Thermoelectric Properties of Scaled Silicon Nanowires Using an Atomistic Tight Abstract Low dimensional materials provide the possibility of improved thermoelectric performance due. As a result of suppressed phonon conduction, large improvements on the thermoelectric figure of merit, ZT

435

Multi-length scale analysis of chemical vapor deposition (CVD) of diamond and titanium nitride films  

NASA Astrophysics Data System (ADS)

Chemical vapor deposition (CVD) is a widely used method for preparation of thin films and micron-thick coatings. Up to now, major advances in the development of the CVD process and in obtaining high-quality films and coatings have been achieved by trial and error. In the present work, a multi-length scale computer modeling and simulation methodology is developed to analyze the CVD process and the evolution of the film/coating microstructure during deposition. The multi-length scale model developed in the present work consists of three parts each analyzing the CVD process at different length scales: (a) At the chemical reactor length scale, the CVD process is analyzed by solving the appropriate reactive-gas, fluid-dynamics, heat-transfer boundary value problem; (b) At the atomic scale, a kinetic Monte Carlo method is utilized to model, in a stochastic manner, the deposition process of single crystalline films and the growth of polycrystalline film facets, and (c) At the grain scale, an improved van der Drift-type model is employed to simulate the evolution of microstructural and crystallographic texture of polycrystalline films and coatings. The three modeling schemes are coupled to each other so that the results obtained on one length-scale can be utilized when modeling is carried out at a different length scale. The reactor scale modeling predicts the concentration of gas-phase and surface species on the deposition surface which are used as input to the atomic scale modeling. Also, the atomic scale model predicts the growth rates of (111)- and (100)-oriented surface facets and the rates of defect incorporation which are used as input to the grain scale modeling. To ensure the consistency in prediction of different models, the exchange of information between the models is enabled to be in both directions. The method developed in the present work is subsequently used to analyze the CVD of single and polycrystalline diamond films and TiN coatings. The results of the analysis show that the multi-length scale model enables establishment of the relationships between the process parameters, and the properties and performance of the deposited films and coatings.

Lai, Shugang

2000-10-01

436

Fine-Scale Analysis Reveals Cryptic Landscape Genetic Structure in Desert Tortoises  

PubMed Central

Characterizing the effects of landscape features on genetic variation is essential for understanding how landscapes shape patterns of gene flow and spatial genetic structure of populations. Most landscape genetics studies have focused on patterns of gene flow at a regional scale. However, the genetic structure of populations at a local scale may be influenced by a unique suite of landscape variables that have little bearing on connectivity patterns observed at broader spatial scales. We investigated fine-scale spatial patterns of genetic variation and gene flow in relation to features of the landscape in desert tortoise (Gopherus agassizii), using 859 tortoises genotyped at 16 microsatellite loci with associated data on geographic location, sex, elevation, slope, and soil type, and spatial relationship to putative barriers (power lines, roads). We used spatially explicit and non-explicit Bayesian clustering algorithms to partition the sample into discrete clusters, and characterize the relationships between genetic distance and ecological variables to identify factors with the greatest influence on gene flow at a local scale. Desert tortoises exhibit weak genetic structure at a local scale, and we identified two subpopulations across the study area. Although genetic differentiation between the subpopulations was low, our landscape genetic analysis identified both natural (slope) and anthropogenic (roads) landscape variables that have significantly influenced gene flow within this local population. We show that desert tortoise movements at a local scale are influenced by features of the landscape, and that these features are different than those that influence gene flow at larger scales. Our findings are important for desert tortoise conservation and management, particularly in light of recent translocation efforts in the region. More generally, our results indicate that recent landscape changes can affect gene flow at a local scale and that their effects can be detected almost immediately. PMID:22132143

Latch, Emily K.; Boarman, William I.; Walde, Andrew; Fleischer, Robert C.

2011-01-01

437

Scale-4 Analysis of Pressurized Water Reactor Critical Configurations: Volume 3-Surry Unit 1 Cycle 2  

SciTech Connect

The requirements of ANSI/ANS 8.1 specify that calculational methods for away-from-reactor criticality safety analyses be validated against experimental measurements. If credit for the negative reactivity of the depleted (or spent) fuel isotopics is desired, it is necessary to benchmark computational methods against spent fuel critical configurations. This report summarizes a portion of the ongoing effort to benchmark away-from-reactor criticality analysis methods using selected critical configurations from commercial pressurized-water reactors. The analysis methodology selected for all the calculations in this report is based on the codes and data provided in the SCALE-4 code system. The isotopic densities for the spent fuel assemblies in the critical configurations were calculated using the SAS2H analytical sequence of the SCALE-4 system. The sources of data and the procedures for deriving SAS2H input parameters are described in detail. The SNIKR code module was used to extract the necessary isotopic densities from the SAS2H results and to provide the data in the format required by the SCALE criticality analysis modules. The CSASN analytical sequence in SCALE-4 was used to perform resonance processing of the cross sections. The KENO V.a module of SCALE-4 was used to calculate the effective multiplication factor (k{sub eff}) of each case. The SCALE-4 27-group burnup library containing ENDF/B-IV (actinides) and ENDF/B-V (fission products) data was used for all the calculations. This volume of the report documents the SCALE system analysis of two reactor critical configurations for Surry Unit 1 Cycle 2. This unit and cycle were chosen for a previous analysis using a different methodology because detailed isotopics from multidimensional reactor calculations were available from the Virginia Power Company. These data permitted a direct comparison of criticality calculations using the utility-calculated isotopics with those using the isotopics generated by the SCALE-4 SAS2H sequence. These reactor critical benchmarks have been reanalyzed using the methodology described above. The two benchmark critical calculations were the beginning-of-cycle (BOC) startup at hot, zero-power (HZP) and an end-of-cycle (EOC) critical at hot, full-power (HFP) critical conditions. These calculations were used to check for consistency in the calculated results for different burnup, downtime, temperature, xenon, and boron conditions. The k{sub eff} results were 1.0014 and 1.0113, respectively, with a standard deviation of 0.0005.

Bowman, S.M.

1995-01-01

438

Errors in Quantitative Image Analysis due to Platform-Dependent Image Scaling1  

PubMed Central

PURPOSE: To evaluate the ability of various software (SW) tools used for quantitative image analysis to properly account for source-specific image scaling employed by magnetic resonance imaging manufacturers. METHODS: A series of gadoteridol-doped distilled water solutions (0%, 0.5%, 1%, and 2% volume concentrations) was prepared for manual substitution into one (of three) phantom compartments to create “variable signal,” whereas the other two compartments (containing mineral oil and 0.25% gadoteriol) were held unchanged. Pseudodynamic images were acquired over multiple series using four scanners such that the histogram of pixel intensities varied enough to provoke variable image scaling from series to series. Additional diffusion-weighted images were acquired of an ice-water phantom to generate scanner-specific apparent diffusion coefficient (ADC) maps. The resulting pseudodynamic images and ADC maps were analyzed by eight centers of the Quantitative Imaging Network using 16 different SW tools to measure compartment-specific region-of-interest intensity. RESULTS: Images generated by one of the scanners appeared to have additional intensity scaling that was not accounted for by the majority of tested quantitative image analysis SW tools. Incorrect image scaling leads to intensity measurement bias near 100%, compared to nonscaled images. CONCLUSION: Corrective actions for image scaling are suggested for manufacturers and quantitative imaging community. PMID:24772209

Chenevert, Thomas L; Malyarenko, Dariya I; Newitt, David; Li, Xin; Jayatilake, Mohan; Tudorica, Alina; Fedorov, Andriy; Kikinis, Ron; Liu, Tiffany Ting; Muzi, Mark; Oborski, Matthew J; Laymon, Charles M; Li, Xia; Thomas, Yankeelov; Jayashree, Kalpathy-Cramer; Mountz, James M; Kinahan, Paul E; Rubin, Daniel L; Fennessy, Fiona; Huang, Wei; Hylton, Nola; Ross, Brian D

2014-01-01

439

A Rasch model analysis of NEO PI-R fearless dominance and impulsive antisociality scales.  

PubMed

This study reports a Rasch model analysis of psychopathic trait measures of fearless dominance and impulsive antisociality (Witt et al., 2010). Through use of secondary data analysis (N = 200), these scales were evaluated to determine whether they provided effective dimensional measurement evidenced by a) one-dimensional structure, b) broad targeting of the latent dimensions, and c) invariance across men and women. Only fearless dominance achieved an invariant one-dimensional structure after slight modification. Both fearless dominance and impulsive antisociality had a restricted range in targeting of the latent trait dimensions. With one exception, scale items did not exhibit differential item functioning across men and women. Implications of the results are discussed within the context of Rasch analysis and the conceptualization of psychopathy. PMID:23148677

Ruiz, Mark A; Pincus, Aaron L

2013-04-01

440

Data-Adaptive Wavelets and Multi-Scale Singular Spectrum Analysis  

E-print Network

Using multi-scale ideas from wavelet analysis, we extend singular-spectrum analysis (SSA) to the study of nonstationary time series of length $N$ whose intermittency can give rise to the divergence of their variance. SSA relies on the construction of the lag-covariance matrix C on M lagged copies of the time series over a fixed window width W to detect the regular part of the variability in that window in terms of the minimal number of oscillatory components; here W = M Dt, with Dt the time step. The proposed multi-scale SSA is a local SSA analysis within a moving window of width M years supports the Devil's staircase scenario for the El Nino/Southern Oscillation phenomenon.

P. Yiou; D. Sornette; M. Ghil

1998-10-29