Issues in cross-cultural validity: example from the adaptation, reliability, and validity testing of a Turkish version of the Stanford Health Assessment Questionnaire.

PubMed

Küçükdeveci, Ayse A; Sahin, Hülya; Ataman, Sebnem; Griffiths, Bridget; Tennant, Alan

2004-02-15

Guidelines have been established for cross-cultural adaptation of outcome measures. However, invariance across cultures must also be demonstrated through analysis of Differential Item Functioning (DIF). This is tested in the context of a Turkish adaptation of the Health Assessment Questionnaire (HAQ). Internal construct validity of the adapted HAQ is assessed by Rasch analysis; reliability, by internal consistency and the intraclass correlation coefficient; external construct validity, by association with impairments and American College of Rheumatology functional stages. Cross-cultural validity is tested through DIF by comparison with data from the UK version of the HAQ. The adapted version of the HAQ demonstrated good internal construct validity through fit of the data to the Rasch model (mean item fit 0.205; SD 0.998). Reliability was excellent (alpha = 0.97) and external construct validity was confirmed by expected associations. DIF for culture was found in only 1 item. Cross-cultural validity was found to be sufficient for use in international studies between the UK and Turkey. Future adaptation of instruments should include analysis of DIF at the field testing stage in the adaptation process.

Postcolonial constructions of HIV/AIDS: meaning, culture, and structure.

PubMed

Sastry, Shaunak; Dutta, Mohan J

2011-01-01

As a field of inquiry, postcolonial health communication seeks to apprehend processes implicated in the construction of "primitive" versus "modern" with respect to issues of health. In the case of HIV/AIDS, the sociocultural representations of the disease have a profound impact on how the disease is configured medically and symbolically in dominant cultural imagination. Postcolonial constructions of disease are mobilized around the political and economic interests of the dominant power structures in global spaces. In this article, a thematic analysis of the constructions of HIV/AIDS in India in the mainstream U.S. news media was conducted. A corpus of news articles from the Lexis-Nexis database was created with the keywords "HIV," "AIDS," and "India." Three themes emerged from the study: (a) India as a site of biomedical control; (b) the economic logics of HIV/AIDS; and (c) AIDS, development, and the "Third World." Copyright © Taylor & Francis Group, LLC

A Constructive Mean-Field Analysis of Multi-Population Neural Networks with Random Synaptic Weights and Stochastic Inputs

PubMed Central

Faugeras, Olivier; Touboul, Jonathan; Cessac, Bruno

2008-01-01

We deal with the problem of bridging the gap between two scales in neuronal modeling. At the first (microscopic) scale, neurons are considered individually and their behavior described by stochastic differential equations that govern the time variations of their membrane potentials. They are coupled by synaptic connections acting on their resulting activity, a nonlinear function of their membrane potential. At the second (mesoscopic) scale, interacting populations of neurons are described individually by similar equations. The equations describing the dynamical and the stationary mean-field behaviors are considered as functional equations on a set of stochastic processes. Using this new point of view allows us to prove that these equations are well-posed on any finite time interval and to provide a constructive method for effectively computing their unique solution. This method is proved to converge to the unique solution and we characterize its complexity and convergence rate. We also provide partial results for the stationary problem on infinite time intervals. These results shed some new light on such neural mass models as the one of Jansen and Rit (1995): their dynamics appears as a coarse approximation of the much richer dynamics that emerges from our analysis. Our numerical experiments confirm that the framework we propose and the numerical methods we derive from it provide a new and powerful tool for the exploration of neural behaviors at different scales. PMID:19255631

7 CFR 1737.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

.... Feasibility study means the pro forma financial analysis performed by RUS to determine the economic... RUS to the borrower's construction fund. Borrower means any organization which has an outstanding loan... percent per year. Initial loan means the first loan made to a borrower. Interim construction means the...

7 CFR 1737.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

.... Feasibility study means the pro forma financial analysis performed by RUS to determine the economic... RUS to the borrower's construction fund. Borrower means any organization which has an outstanding loan... percent per year. Initial loan means the first loan made to a borrower. Interim construction means the...

7 CFR 1737.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

.... Feasibility study means the pro forma financial analysis performed by RUS to determine the economic... RUS to the borrower's construction fund. Borrower means any organization which has an outstanding loan... percent per year. Initial loan means the first loan made to a borrower. Interim construction means the...

7 CFR 1737.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

.... Feasibility study means the pro forma financial analysis performed by RUS to determine the economic... RUS to the borrower's construction fund. Borrower means any organization which has an outstanding loan... percent per year. Initial loan means the first loan made to a borrower. Interim construction means the...

7 CFR 1737.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

.... Feasibility study means the pro forma financial analysis performed by RUS to determine the economic... RUS to the borrower's construction fund. Borrower means any organization which has an outstanding loan... percent per year. Initial loan means the first loan made to a borrower. Interim construction means the...

Statistical mechanics framework for static granular matter.

PubMed

Henkes, Silke; Chakraborty, Bulbul

2009-06-01

The physical properties of granular materials have been extensively studied in recent years. So far, however, there exists no theoretical framework which can explain the observations in a unified manner beyond the phenomenological jamming diagram. This work focuses on the case of static granular matter, where we have constructed a statistical ensemble which mirrors equilibrium statistical mechanics. This ensemble, which is based on the conservation properties of the stress tensor, is distinct from the original Edwards ensemble and applies to packings of deformable grains. We combine it with a field theoretical analysis of the packings, where the field is the Airy stress function derived from the force and torque balance conditions. In this framework, Point J characterized by a diverging stiffness of the pressure fluctuations. Separately, we present a phenomenological mean-field theory of the jamming transition, which incorporates the mean contact number as a variable. We link both approaches in the context of the marginal rigidity picture proposed by Wyart and others.

7 CFR 1738.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... means the pro forma financial analysis prepared by the applicant, and acceptable to RUS, to determine... years estimated in the feasibility study for completion of the construction covered by the loan... the RE Act to each eligible entity. Interim construction means the construction, improvement, or...

7 CFR 1738.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... means the pro forma financial analysis prepared by the applicant, and acceptable to RUS, to determine... years estimated in the feasibility study for completion of the construction covered by the loan... the RE Act to each eligible entity. Interim construction means the construction, improvement, or...

The Construction of a New Science by Means of an Institute and Its Communication Media: The Institute of Educational Sciences in Geneva (1912-1948)

ERIC Educational Resources Information Center

Hofstetter, Rita

2004-01-01

This article is aimed at understanding some mechanisms implied in the construction of educational sciences as a disciplinary field in interaction with other social fields. Its object is the Genevan "Institut des sciences de l'education" from 1912 to 1948. This institution is analyzed from two main points of view: the foundation and…

Characteristics of buoyancy force on stagnation point flow with magneto-nanoparticles and zero mass flux condition

NASA Astrophysics Data System (ADS)

Uddin, Iftikhar; Khan, Muhammad Altaf; Ullah, Saif; Islam, Saeed; Israr, Muhammad; Hussain, Fawad

2018-03-01

This attempt dedicated to the solution of buoyancy effect over a stretching sheet in existence of MHD stagnation point flow with convective boundary conditions. Thermophoresis and Brownian motion aspects are included. Incompressible fluid is electrically conducted in the presence of varying magnetic field. Boundary layer analysis is used to develop the mathematical formulation. Zero mass flux condition is considered at the boundary. Non-linear ordinary differential system of equations is constructed by means of proper transformations. Interval of convergence via numerical data and plots are developed. Characteristics of involved variables on the velocity, temperature and concentration distributions are sketched and discussed. Features of correlated parameters on Cf and Nu are examined by means of tables. It is found that buoyancy ratio and magnetic parameters increase and reduce the velocity field. Further opposite feature is noticed for higher values of thermophoresis and Brownian motion parameters on concentration distribution.

Unified functional network and nonlinear time series analysis for complex systems science: The pyunicorn package

NASA Astrophysics Data System (ADS)

Donges, Jonathan F.; Heitzig, Jobst; Beronov, Boyan; Wiedermann, Marc; Runge, Jakob; Feng, Qing Yi; Tupikina, Liubov; Stolbova, Veronika; Donner, Reik V.; Marwan, Norbert; Dijkstra, Henk A.; Kurths, Jürgen

2015-11-01

We introduce the pyunicorn (Pythonic unified complex network and recurrence analysis toolbox) open source software package for applying and combining modern methods of data analysis and modeling from complex network theory and nonlinear time series analysis. pyunicorn is a fully object-oriented and easily parallelizable package written in the language Python. It allows for the construction of functional networks such as climate networks in climatology or functional brain networks in neuroscience representing the structure of statistical interrelationships in large data sets of time series and, subsequently, investigating this structure using advanced methods of complex network theory such as measures and models for spatial networks, networks of interacting networks, node-weighted statistics, or network surrogates. Additionally, pyunicorn provides insights into the nonlinear dynamics of complex systems as recorded in uni- and multivariate time series from a non-traditional perspective by means of recurrence quantification analysis, recurrence networks, visibility graphs, and construction of surrogate time series. The range of possible applications of the library is outlined, drawing on several examples mainly from the field of climatology.

Applying Longitudinal Mean and Covariance Structures (LMACS) Analysis to Assess Construct Stability Over Two Time Points: An Example Using Psychological Entitlement

ERIC Educational Resources Information Center

Bashkov, Bozhidar M.; Finney, Sara J.

2013-01-01

Traditional methods of assessing construct stability are reviewed and longitudinal mean and covariance structures (LMACS) analysis, a modern approach, is didactically illustrated using psychological entitlement data. Measurement invariance and latent variable stability results are interpreted, emphasizing substantive implications for educators and…

Embodied Design: Constructing Means for Constructing Meaning

ERIC Educational Resources Information Center

Abrahamson, Dor

2009-01-01

Design-based research studies are conducted as iterative implementation-analysis-modification cycles, in which emerging theoretical models and pedagogically plausible activities are reciprocally tuned toward each other as a means of investigating conjectures pertaining to mechanisms underlying content teaching and learning. Yet this approach, even…

New Metrics from a Fractional Gravitational Field

NASA Astrophysics Data System (ADS)

El-Nabulsi, Rami Ahmad

2017-09-01

Agop et al. proved in Commun. Theor. Phys. (2008) that, a Reissner-Nordstrom type metric is obtained, if gauge gravitational field in a fractal spacetime is constructed by means of concepts of scale relativity. We prove in this short communication that similar result is obtained if gravity in D-spacetime dimensions is fractionalized by means of the Glaeske-Kilbas-Saigo fractional. Besides, non-singular gravitational fields are obtained without using extra-dimensions. We present few examples to show that these gravitational fields hold a number of motivating features in spacetime physics.

Emotional and cognitive effects of peer tutoring among secondary school mathematics students

NASA Astrophysics Data System (ADS)

Alegre Ansuategui, Francisco José; Moliner Miravet, Lidón

2017-11-01

This paper describes an experience of same-age peer tutoring conducted with 19 eighth-grade mathematics students in a secondary school in Castellon de la Plana (Spain). Three constructs were analysed before and after launching the program: academic performance, mathematics self-concept and attitude of solidarity. Students' perceptions of the method were also analysed. The quantitative data was gathered by means of a mathematics self-concept questionnaire, an attitude of solidarity questionnaire and the students' numerical ratings. A statistical analysis was performed using Student's t-test. The qualitative information was gathered by means of discussion groups and a field diary. This information was analysed using descriptive analysis and by categorizing the information. Results show statistically significant improvements in all the variables and the positive assessment of the experience and the interactions that took place between the students.

Theoretical exploration of competing phases of lattice Bose gases in a cavity

NASA Astrophysics Data System (ADS)

Liao, Renyuan; Chen, Huang-Jie; Zheng, Dong-Chen; Huang, Zhi-Gao

2018-01-01

We consider bosonic atoms loaded into optical lattices with cavity-mediated infinite-range interactions. Competing short- and global-range interactions cultivate a rich phase diagram. With a systematic field-theoretical perspective, we present an analytical construction of a global ground-state phase diagram. We find that the infinite-range interaction enhances the fluctuation of the number density. In the strong-coupling regime, we find four branches of elementary excitations, with two being "particlelike" and two being "holelike," and that the excitation gap becomes soft at the phase boundary between compressible phases and incompressible phases. We derive an effective theory describing compressible superfluid and supersolid states. To complement this perturbative study, we construct a self-consistent mean-field theory and find numerical results consistent with our theoretical analysis. We map out the phase diagram and find that a charge density wave may undergo a structure phase transition to a different charge density wave before it finally enters into the supersolid phase driven by increasing the hopping amplitude.

Gauge Fields in Homogeneous and Inhomogeneous Cosmologies

NASA Astrophysics Data System (ADS)

Darian, Bahman K.

Despite its formidable appearance, the study of classical Yang-Mills (YM) fields on homogeneous cosmologies is amenable to a formal treatment. This dissertation is a report on a systematic approach to the general construction of invariant YM fields on homogeneous cosmologies undertaken for the first time in this context. This construction is subsequently followed by the investigation of the behavior of YM field variables for the most simple of self-gravitating YM fields. Particularly interesting was a dynamical system analysis and the discovery of chaotic signature in the axially symmetric Bianchi I-YM cosmology. Homogeneous YM fields are well studied and are known to have chaotic properties. The chaotic behavior of YM field variables in homogeneous cosmologies might eventually lead to an invariant definition of chaos in (general) relativistic cosmological models. By choosing the gauge fields to be Abelian, the construction and the field equations presented so far reduce to that of electromagnetic field in homogeneous cosmologies. A perturbative analysis of gravitationally interacting electromagnetic and scalar fields in inhomogeneous cosmologies is performed via the Hamilton-Jacobi formulation of general relativity. An essential feature of this analysis is the spatial gradient expansion of the generating functional (Hamilton principal function) to solve the Hamiltonian constraint. Perturbations of a spatially flat Friedman-Robertson-Walker cosmology with an exponential potential for the scalar field are presented.

Analysis of administrative barriers in the industry of the high-rise construction in Russian Federation

NASA Astrophysics Data System (ADS)

Zaychenko, Irina; Borremans, Alexandra; Gutman, Svetlana

2018-03-01

The article describes the concept and types of administrative barriers encountered in various areas of the enterprise. The particularities of the Russian high-rise construction industry are described and a comparative analysis of administrative barriers in this sector is performed. The main stages and administrative procedures when the developers implement investment and construction projects in the field of high-rise construction are determined. The regulatory and legal framework for the implementation of investment and project activities in the high-rise construction industry has been studied and conclusions have been drawn on its low level of precision in the issue of the formation of competitive and efficient high-rise construction markets. The average number of administrative procedures for the implementation of the investment and construction project in the field of high-rise construction is determined. The factors preventing the reduction of administrative barriers in the high-rise construction industry are revealed.

Constructional and Conceptual Composition

ERIC Educational Resources Information Center

Dodge, Ellen Kirsten

2010-01-01

Goldberg's (1995) recognition that, in addition to various word-level constructions, sentences also instantiate meaningful argument structure constructions enables a non-polysemy-based analysis of various verb 'alternations' (Levin 1993). In such an analysis, meaning variations associated with the use of the same verb in different argument…

An Inquiry into the Nature of Uncle Joe's Representation and Meaning.

ERIC Educational Resources Information Center

Muffoletto, Robert

2001-01-01

Addresses a "critical" or "reflective" visual literacy. Situates visual representations and their interpretation (the construction of meaning) within a context that raises questions about benefit and power. Explores four main topics: the image as text; analysis and meaning construction; visual literacy as a liberatory practice;…

Social Constructionism and Ludology: Implications for the Study of Games

ERIC Educational Resources Information Center

Montola, Markus

2012-01-01

This article combines the paradigm of social constructionism with the developing field of ludology. As games are intersubjective meaning-making activities, their study requires understanding of the nature of social constructions, and how such constructions are produced and interpreted: The formalist nature of ludological core concepts such as game…

PFGE MAPPER and PFGE READER: two tools to aid in the analysis and data input of pulse field gel electrophoresis maps.

PubMed Central

Shifman, M. A.; Nadkarni, P.; Miller, P. L.

1992-01-01

Pulse field gel electrophoresis mapping is an important technique for characterizing large segments of DNA. We have developed two tools to aid in the construction of pulse field electrophoresis gel maps: PFGE READER which stores experimental conditions and calculates fragment sizes and PFGE MAPPER which constructs pulse field gel electrophoresis maps. PMID:1482898

Development of a source-exposure matrix for occupational exposure assessment of electromagnetic fields in the INTEROCC study

PubMed Central

Vila, Javier; Bowman, Joseph D; Figuerola, Jordi; Moriña, David; Kincl, Laurel; Richardson, Lesley; Cardis, Elisabeth

2017-01-01

Introduction To estimate occupational exposures to electromagnetic fields (EMF) for the INTEROCC study, a database of source-based measurements extracted from published and unpublished literature resources had been previously constructed. The aim of the current work was to summarize these measurements into a source-exposure matrix (SEM), accounting for their quality and relevance. Methods A novel methodology for combining available measurements was developed, based on order statistics and log-normal distribution characteristics. Arithmetic and geometric means, and estimates of variability and maximum exposure were calculated by EMF source, frequency band and dosimetry type. Mean estimates were weighted by our confidence on the pooled measurements. Results The SEM contains confidence-weighted mean and maximum estimates for 312 EMF exposure sources (from 0 Hz to 300 GHz). Operator position geometric mean electric field levels for RF sources ranged between 0.8 V/m (plasma etcher) and 320 V/m (RF sealer), while magnetic fields ranged from 0.02 A/m (speed radar) to 0.6 A/m (microwave heating). For ELF sources, electric fields ranged between 0.2 V/m (electric forklift) and 11,700 V/m (HVTL-hotsticks), while magnetic fields ranged between 0.14 μT (visual display terminals) and 17 μT (TIG welding). Conclusion The methodology developed allowed the construction of the first EMF-SEM and may be used to summarize similar exposure data for other physical or chemical agents. PMID:27827378

Human and Organizational Factors in the U.S. Naval Construction Force: A Qualitative Analysis of the U.S. Naval Mobile Construction Battalion Peacetime Deployment Construction Program

DTIC Science & Technology

2002-09-01

a program in its weapons systems acquisition program known as HARDMAN (Hardware/ Manpower Comparability Analysis Methodology) which combined...battalion-wide real-time training exercises out in the field each homeport. These field exercises are driven by tactical scenarios that tax the full range...received the proper training for your rating during A-School? q 1 q 2 q 3 q 4 q 5 q 6 q 7 If not, why not

Constructing Knowledge about the Trigonometric Functions and Their Geometric Meaning on the Unit Circle

ERIC Educational Resources Information Center

Altman, Renana; Kidron, Ivy

2016-01-01

Processes of knowledge construction are investigated. A learner is constructing knowledge about the trigonometric functions and their geometric meaning on the unit circle. The analysis is based on the dynamically nested epistemic action model for abstraction in context. Different tasks are offered to the learner. In his effort to perform the…

A Novel Quantitative Approach to Concept Analysis: The Internomological Network

PubMed Central

Cook, Paul F.; Larsen, Kai R.; Sakraida, Teresa J.; Pedro, Leli

2012-01-01

Background When a construct such as patients’ transition to self-management of chronic illness is studied by researchers across multiple disciplines, the meaning of key terms can become confused. This results from inherent problems in language where a term can have multiple meanings (polysemy) and different words can mean the same thing (synonymy). Objectives To test a novel quantitative method for clarifying the meaning of constructs by examining the similarity of published contexts in which they are used. Method Published terms related to the concept transition to self-management of chronic illness were analyzed using the internomological network (INN), a type of latent semantic analysis to calculate the mathematical relationships between constructs based on the contexts in which researchers use each term. This novel approach was tested by comparing results to those from concept analysis, a best-practice qualitative approach to clarifying meanings of terms. By comparing results of the two methods, the best synonyms of transition to self-management, as well as key antecedent, attribute, and consequence terms, were identified. Results Results from INN analysis were consistent with those from concept analysis. The potential synonyms self-management, transition, and adaptation had the greatest utility. Adaptation was the clearest overall synonym, but had lower cross-disciplinary use. The terms coping and readiness had more circumscribed meanings. The INN analysis confirmed key features of transition to self-management, and suggested related concepts not found by the previous review. Discussion The INN analysis is a promising novel methodology that allows researchers to quantify the semantic relationships between constructs. The method works across disciplinary boundaries, and may help to integrate the diverse literature on self-management of chronic illness. PMID:22592387

Transport induced by mean-eddy interaction: II. Analysis of transport processes

NASA Astrophysics Data System (ADS)

Ide, Kayo; Wiggins, Stephen

2015-03-01

We present a framework for the analysis of transport processes resulting from the mean-eddy interaction in a flow. The framework is based on the Transport Induced by the Mean-Eddy Interaction (TIME) method presented in a companion paper (Ide and Wiggins, 2014) [1]. The TIME method estimates the (Lagrangian) transport across stationary (Eulerian) boundaries defined by chosen streamlines of the mean flow. Our framework proceeds after first carrying out a sequence of preparatory steps that link the flow dynamics to the transport processes. This includes the construction of the so-called "instantaneous flux" as the Hovmöller diagram. Transport processes are studied by linking the signals of the instantaneous flux field to the dynamical variability of the flow. This linkage also reveals how the variability of the flow contributes to the transport. The spatio-temporal analysis of the flux diagram can be used to assess the efficiency of the variability in transport processes. We apply the method to the double-gyre ocean circulation model in the situation where the Rossby-wave mode dominates the dynamic variability. The spatio-temporal analysis shows that the inter-gyre transport is controlled by the circulating eddy vortices in the fast eastward jet region, whereas the basin-scale Rossby waves have very little impact.

A thermo-physical analysis of the proton pump vacuolar-ATPase: the constructal approach.

PubMed

Lucia, Umberto; Ponzetto, Antonio; Deisboeck, Thomas S

2014-10-24

Pumping protons across a membrane was a critical step at the origin of life on earth, and it is still performed in all living organisms, including in human cells. Proton pumping is paramount to keep normal cells alive, e.g. for lysosomal digestion and for preparing peptides for immune recognition, but it goes awry in cancer cells. They acidify their microenvironment hence membrane voltage is lowered, which in turn induces cell proliferation, a hallmark of cancer. Proton pumping is achieved by means of rotary motors, namely vacuolar ATPases (V-ATPase), which are present at many of the multiple cellular interfaces. Therefore, we undertook an examination of the thermodynamic properties of V-ATPases. The principal result is that the V-ATPase-mediated control of the cell membrane potential and the related and consequent environmental pH can potentially represent a valuable support strategy for anticancer therapies. A constructal theory approach is used as a new viewpoint to study how V-ATPase can be modulated for therapeutic purposes. In particular, V-ATPase can be regulated by using external fields, such as electromagnetic fields, and a theoretical approach has been introduced to quantify the appropriate field strength and frequency for this new adjuvant therapeutic strategy.

Analysis on the hot spot and trend of the foreign assembly building research

NASA Astrophysics Data System (ADS)

Bi, Xiaoqing; Luo, Yanbing

2017-03-01

First of all, the paper analyzes the research on the front of the assembly building in the past 15 years. This article mainly adopts the method of CO word analysis, construct the co word matrix, correlation matrix, and then into a dissimilarity matrix, and on this basis, using factor analysis, cluster analysis and multi scale analysis method to study the structure of prefabricated construction field display. Finally, the results of the analysis are discussed, and summarized the current research focus of foreign prefabricated construction mainly concentrated in 7 aspects: embankment construction, wood construction, bridge construction, crane layout, PCM wall and glass system, based on neural network test, energy saving and recycling, and forecast the future trend of development study.

Simulation analysis of temperature control on RCC arch dam of hydropower station

NASA Astrophysics Data System (ADS)

XIA, Shi-fa

2017-12-01

The temperature analysis of roller compacted concrete (RCC) dam plays an important role in their design and construction. Based on three-dimensional finite element method, in the computation of temperature field, many cases are included, such as air temperature, elevated temperature by cement hydration heat, concrete temperature during placing, the influence of water in the reservoir, and boundary temperature. According to the corresponding parameters of RCC arch dam, the analysis of temperature field and stress field during the period of construction and operation is performed. The study demonstrates that detailed thermal stress analysis should be performed for RCC dams to provide a basis to minimize and control the occurrence of thermal cracking.

An economic analysis of alternative paving materials

NASA Astrophysics Data System (ADS)

Mustain, J. L.

1982-12-01

The purpose of this paper is to present a means for economic analysis of alternative equivalent pavement designs, considering such factors as initial construction cost, annual maintenance cost, salvage value and the various intangibles which occur during the analysis period. Having established a means of economic comparison, it is then the intent of this paper to show that Portland Cement Concrete has been and is a viable pavement alternative and ought to receive due consideration in the military construction program.

Large scale EMF in current sheets induced by tearing modes

NASA Astrophysics Data System (ADS)

Mizerski, Krzysztof A.

2018-02-01

An extension of the analysis of resistive instabilities of a sheet pinch from a famous work by Furth et al (1963 Phys. Fluids 6 459) is presented here, to study the mean electromotive force (EMF) generated by the developing instability. In a Cartesian configuration and in the presence of a current sheet first the boundary layer technique is used to obtain global, matched asymptotic solutions for the velocity and magnetic field and then the solutions are used to calculate the large-scale EMF in the system. It is reported, that in the bulk the curl of the mean EMF is linear in {{j}}0\\cdot {{B}}0, a simple pseudo-scalar quantity constructed from the large-scale quantities.

Phase transition studies of BiMnO3: Mean field theory approximations

NASA Astrophysics Data System (ADS)

Priya K. B, Lakshmi; Natesan, Baskaran

2015-06-01

We studied the phase transition and magneto-electric coupling effect of BiMnO3 by employing mean field theory approximations. To capture the ferromagnetic and ferroelectric transitions of BiMnO3, we construct an extended Ising model in a 2D square lattice, wherein, the magnetic (electric) interactions are described in terms of the direct interactions between the localized magnetic (electric dipole) moments of Mn ions with their nearest neighbors. To evaluate our model, we obtain magnetization, magnetic susceptibility and electric polarization using mean field approximation calculations. Our results reproduce both the ferromagnetic and the ferroelectric transitions, matching very well with the experimental reports. Furthermore, consistent with experimental observations, our mean field results suggest that there is indeed a coupling between the magnetic and electric ordering in BiMnO3.

The Analysis and Construction of Perfectly Matched Layers for the Linearized Euler Equations

NASA Technical Reports Server (NTRS)

Hesthaven, J. S.

1997-01-01

We present a detailed analysis of a recently proposed perfectly matched layer (PML) method for the absorption of acoustic waves. The split set of equations is shown to be only weakly well-posed, and ill-posed under small low order perturbations. This analysis provides the explanation for the stability problems associated with the split field formulation and illustrates why applying a filter has a stabilizing effect. Utilizing recent results obtained within the context of electromagnetics, we develop strongly well-posed absorbing layers for the linearized Euler equations. The schemes are shown to be perfectly absorbing independent of frequency and angle of incidence of the wave in the case of a non-convecting mean flow. In the general case of a convecting mean flow, a number of techniques is combined to obtain a absorbing layers exhibiting PML-like behavior. The efficacy of the proposed absorbing layers is illustrated though computation of benchmark problems in aero-acoustics.

Virtual and Virtuous Realities of Workplace Literacy.

ERIC Educational Resources Information Center

Castleton, Geraldine

Workplace literacy has been a recent addition to the field of literacy education and research, achieving a level of "commonsense" acceptability so that its meaning(s) or constructions have largely gone unchallenged. A study, therefore, explored the concepts of "work,""workers," and "literacy," not so much to…

Thermal Analysis of a Structural Solution for Sustainable, Modular and Prefabricated Buildings

NASA Astrophysics Data System (ADS)

Isopescu, D. N.; Maxineasa, S. G.; Neculai, O.

2017-06-01

In the construction field, the design principles for an efficient and operational use of buildings and a minimal impact on the environment are essential aspects of sustainable development. In this regard, several aspects must be taken into consideration, such as: durability, easy maintenance, flexibility in interior design, and reduced energy consumption. Decreasing energy consumption in buildings during the service life (heating / cooling / drinking water / electricity) can mean lower costs, but also a lower impact on the environment. The paper presents the thermal analysis for a GF+1F height structure, consisting of several identical, adjacent and / or overlapped metallic cubic modules. The spaces inside this cubes ensemble solve the functionality of a family home building. The good carrying capacity, the rapidity of execution, the superior degree of thermal insulation and the minimum losses of material in execution were the main advantages provided by this structural solution. Regarding the thermal comfort for the users of this constructive system, the thermal analysis showed that the internal temperatures are constant and uniform, without cold surfaces or temperature fluctuations. In addition, humidity is controlled and there is no risk of condensation.

Development of a source-exposure matrix for occupational exposure assessment of electromagnetic fields in the INTEROCC study.

PubMed

Vila, Javier; Bowman, Joseph D; Figuerola, Jordi; Moriña, David; Kincl, Laurel; Richardson, Lesley; Cardis, Elisabeth

2017-07-01

To estimate occupational exposures to electromagnetic fields (EMF) for the INTEROCC study, a database of source-based measurements extracted from published and unpublished literature resources had been previously constructed. The aim of the current work was to summarize these measurements into a source-exposure matrix (SEM), accounting for their quality and relevance. A novel methodology for combining available measurements was developed, based on order statistics and log-normal distribution characteristics. Arithmetic and geometric means, and estimates of variability and maximum exposure were calculated by EMF source, frequency band and dosimetry type. The mean estimates were weighted by our confidence in the pooled measurements. The SEM contains confidence-weighted mean and maximum estimates for 312 EMF exposure sources (from 0 Hz to 300 GHz). Operator position geometric mean electric field levels for radiofrequency (RF) sources ranged between 0.8 V/m (plasma etcher) and 320 V/m (RF sealer), while magnetic fields ranged from 0.02 A/m (speed radar) to 0.6 A/m (microwave heating). For extremely low frequency sources, electric fields ranged between 0.2 V/m (electric forklift) and 11,700 V/m (high-voltage transmission line-hotsticks), whereas magnetic fields ranged between 0.14 μT (visual display terminals) and 17 μT (tungsten inert gas welding). The methodology developed allowed the construction of the first EMF-SEM and may be used to summarize similar exposure data for other physical or chemical agents.

The Comparability of the Standardized Mean Difference Effect Size across Different Measures of the Same Construct: Measurement Considerations

ERIC Educational Resources Information Center

Nugent, William R.

2006-01-01

One of the most important effect sizes used in meta-analysis is the standardized mean difference (SMD). In this article, the conditions under which SMD effect sizes based on different measures of the same construct are directly comparable are investigated. The results show that SMD effect sizes from different measures of the same construct are…

Comparison of Housing Construction Development in Selected Regions of Central Europe

NASA Astrophysics Data System (ADS)

Dvorský, Ján; Petráková, Zora; Hollý, Ján

2017-12-01

In fast-growing countries, the economic growth, which came after the global financial crisis, ought to be manifested in the development of housing policy. The development of the region is directly related to the increase of the quality of living of its inhabitants. Housing construction and its relation with the availability of housing is a key issue for population overall. Comparison of its development in selected regions is important for experts in the field of construction, mayors of the regions, the state, but especially for the inhabitants themselves. The aim of the article is to compare the number of new dwellings with building permits and completed dwellings with final building approval between selected regions by using a mathematical statistics method - “Analysis of variance”. The article also uses the tools of descriptive statistics such as a point graph, a graph of deviations from the average, basic statistical characteristics of mean and variability. Qualitative factors influencing the construction of flats as well as the causes of quantitative differences in the number of started apartments under construction and completed apartments in selected regions of Central Europe are the subjects of the article’s conclusions.

Modeling Manpower and Equipment Productivity in Tall Building Construction Projects

NASA Astrophysics Data System (ADS)

Mudumbai Krishnaswamy, Parthasarathy; Rajiah, Murugasan; Vasan, Ramya

2017-12-01

Tall building construction projects involve two critical resources of manpower and equipment. Their usage, however, widely varies due to several factors affecting their productivity. Currently, no systematic study for estimating and increasing their productivity is available. What is prevalent is the use of empirical data, experience of similar projects and assumptions. As tall building projects are here to stay and increase, to meet the emerging demands in ever shrinking urban spaces, it is imperative to explore ways and means of scientific productivity models for basic construction activities: concrete, reinforcement, formwork, block work and plastering for the input of specific resources in a mixed environment of manpower and equipment usage. Data pertaining to 72 tall building projects in India were collected and analyzed. Then, suitable productivity estimation models were developed using multiple linear regression analysis and validated using independent field data. It is hoped that the models developed in the study will be useful for quantity surveyors, cost engineers and project managers to estimate productivity of resources in tall building projects.

Work-Related Burn Injuries Hospitalized in US Burn Centers: 2002 to 2011.

PubMed

Huang, Zhenna; Friedman, Lee S

2017-03-01

To develop a comprehensive definition to identify work-related burns in the National Burn Repository (NBR) based on multiple fields and describes injuries by occupation. The NBR, which is an inpatient dataset, was used to compare type and severity of burn injuries by occupation. Using the definition developed for this analysis, 22,969 burn injuries were identified as work-related. In contrast, the single work-related field intended to capture occupational injuries only captured 4696 cases. The highest numbers of burns were observed in construction/extraction, food preparation, and durable goods production occupations. Occupations with a mean total body surface area (TBSA) burned greater than 10% include transportation and material-moving, architecture and engineering, and arts/design/entertainment/sports/media occupations. The NBR dataset should be further utilized for occupational burn injury investigations and multiple fields should be considered for case ascertainment.

Phase transition studies of BiMnO{sub 3}: Mean field theory approximations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lakshmi Priya, K. B.; Natesan, Baskaran, E-mail: nbaski@nitt.edu

We studied the phase transition and magneto-electric coupling effect of BiMnO{sub 3} by employing mean field theory approximations. To capture the ferromagnetic and ferroelectric transitions of BiMnO{sub 3}, we construct an extended Ising model in a 2D square lattice, wherein, the magnetic (electric) interactions are described in terms of the direct interactions between the localized magnetic (electric dipole) moments of Mn ions with their nearest neighbors. To evaluate our model, we obtain magnetization, magnetic susceptibility and electric polarization using mean field approximation calculations. Our results reproduce both the ferromagnetic and the ferroelectric transitions, matching very well with the experimental reports.more » Furthermore, consistent with experimental observations, our mean field results suggest that there is indeed a coupling between the magnetic and electric ordering in BiMnO{sub 3}.« less

Polarizable multipolar electrostatics for cholesterol

NASA Astrophysics Data System (ADS)

Fletcher, Timothy L.; Popelier, Paul L. A.

2016-08-01

FFLUX is a novel force field under development for biomolecular modelling, and is based on topological atoms and the machine learning method kriging. Successful kriging models have been obtained for realistic electrostatics of amino acids, small peptides, and some carbohydrates but here, for the first time, we construct kriging models for a sizeable ligand of great importance, which is cholesterol. Cholesterol's mean total (internal) electrostatic energy prediction error amounts to 3.9 kJ mol-1, which pleasingly falls below the threshold of 1 kcal mol-1 often cited for accurate biomolecular modelling. We present a detailed analysis of the error distributions.

Topological BF Theories

NASA Astrophysics Data System (ADS)

Sǎraru, Silviu-Constantin

Topological field theories originate in the papers of Schwarz and Witten. Initially, Schwarz shown that one of the topological invariants, namely the Ray-Singer torsion, can be represented as the partition function of a certain quantum field theory. Subsequently, Witten constructed a framework for understanding Morse theory in terms of supersymmetric quantum mechanics. These two constructions represent the prototypes of all topological field theories. The model used by Witten has been applied to classical index theorems and, moreover, suggested some generalizations that led to new mathematical results on holomorphic Morse inequalities. Starting with these results, further developments in the domain of topological field theories have been achieved. The Becchi-Rouet-Stora-Tyutin (BRST) symmetry allowed for a new definition of topological ...eld theories as theories whose BRST-invariant Hamiltonian is also BRST-exact. An important class of topological theories of Schwarz type is the class of BF models. This type of models describes three-dimensional quantum gravity and is useful at the study of four-dimensional quantum gravity in Ashtekar-Rovelli-Smolin formulation. Two-dimensional BF models are correlated to Poisson sigma models from various two-dimensional gravities. The analysis of Poisson sigma models, including their relationship to two-dimensional gravity and the study of classical solutions, has been intensively studied in the literature. In this thesis we approach the problem of construction of some classes of interacting BF models in the context of the BRST formalism. In view of this, we use the method of the deformation of the BRST charge and BRST-invariant Hamiltonian. Both methods rely on specific techniques of local BRST cohomology. The main hypotheses in which we construct the above mentioned interactions are: space-time locality, Poincare invariance, smoothness of deformations in the coupling constant and the preservation of the number of derivatives on each field. The first two hypotheses implies that the resulting interacting theory must be local in space-time and Poincare invariant. The smoothness of deformations means that the deformed objects that contribute to the construction of interactions must be smooth in the coupling constant and reduce to the objects corresponding to the free theory in the zero limit of the coupling constant. The preservation of the number of derivatives on each field imp! lies two aspects that must be simultaneously fulfilled: (i) the differential order of each free field equation must coincide with that of the corresponding interacting field equation; (ii) the maximum number of space-time derivatives from the interacting vertices cannot exceed the maximum number of derivatives from the free Lagrangian. The main results obtained can be synthesized into: obtaining self-interactions for certain classes of BF models; generation of couplings between some classes of BF theories and matter theories; construction of interactions between a class of BF models and a system of massless vector fields.

Constructing Meaning from Historical Content: A Research Study

ERIC Educational Resources Information Center

Russell, William Benedict, III; Pellegrino, Anthony

2008-01-01

Through an examination of one undergraduate American history course at a large university in the southeastern United States via interview, observation and content analysis, we attempted to discern if the pedagogical methodology was relating to the students in such a way as to foster students' ability to construct meaning beyond simply…

Modeling asset price processes based on mean-field framework

NASA Astrophysics Data System (ADS)

Ieda, Masashi; Shiino, Masatoshi

2011-12-01

We propose a model of the dynamics of financial assets based on the mean-field framework. This framework allows us to construct a model which includes the interaction among the financial assets reflecting the market structure. Our study is on the cutting edge in the sense of a microscopic approach to modeling the financial market. To demonstrate the effectiveness of our model concretely, we provide a case study, which is the pricing problem of the European call option with short-time memory noise.

Field-theoretic approach to fluctuation effects in neural networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buice, Michael A.; Cowan, Jack D.; Mathematics Department, University of Chicago, Chicago, Illinois 60637

A well-defined stochastic theory for neural activity, which permits the calculation of arbitrary statistical moments and equations governing them, is a potentially valuable tool for theoretical neuroscience. We produce such a theory by analyzing the dynamics of neural activity using field theoretic methods for nonequilibrium statistical processes. Assuming that neural network activity is Markovian, we construct the effective spike model, which describes both neural fluctuations and response. This analysis leads to a systematic expansion of corrections to mean field theory, which for the effective spike model is a simple version of the Wilson-Cowan equation. We argue that neural activity governedmore » by this model exhibits a dynamical phase transition which is in the universality class of directed percolation. More general models (which may incorporate refractoriness) can exhibit other universality classes, such as dynamic isotropic percolation. Because of the extremely high connectivity in typical networks, it is expected that higher-order terms in the systematic expansion are small for experimentally accessible measurements, and thus, consistent with measurements in neocortical slice preparations, we expect mean field exponents for the transition. We provide a quantitative criterion for the relative magnitude of each term in the systematic expansion, analogous to the Ginsburg criterion. Experimental identification of dynamic universality classes in vivo is an outstanding and important question for neuroscience.« less

Design, analysis, and interpretation of field quality-control data for water-sampling projects

USGS Publications Warehouse

Mueller, David K.; Schertz, Terry L.; Martin, Jeffrey D.; Sandstrom, Mark W.

2015-01-01

The report provides extensive information about statistical methods used to analyze quality-control data in order to estimate potential bias and variability in environmental data. These methods include construction of confidence intervals on various statistical measures, such as the mean, percentiles and percentages, and standard deviation. The methods are used to compare quality-control results with the larger set of environmental data in order to determine whether the effects of bias and variability might interfere with interpretation of these data. Examples from published reports are presented to illustrate how the methods are applied, how bias and variability are reported, and how the interpretation of environmental data can be qualified based on the quality-control analysis.

A Cohomological Perspective on Algebraic Quantum Field Theory

NASA Astrophysics Data System (ADS)

Hawkins, Eli

2018-05-01

Algebraic quantum field theory is considered from the perspective of the Hochschild cohomology bicomplex. This is a framework for studying deformations and symmetries. Deformation is a possible approach to the fundamental challenge of constructing interacting QFT models. Symmetry is the primary tool for understanding the structure and properties of a QFT model. This perspective leads to a generalization of the algebraic quantum field theory framework, as well as a more general definition of symmetry. This means that some models may have symmetries that were not previously recognized or exploited. To first order, a deformation of a QFT model is described by a Hochschild cohomology class. A deformation could, for example, correspond to adding an interaction term to a Lagrangian. The cohomology class for such an interaction is computed here. However, the result is more general and does not require the undeformed model to be constructed from a Lagrangian. This computation leads to a more concrete version of the construction of perturbative algebraic quantum field theory.

Uses and Meanings of "Context" in Studies on Children's Knowledge: A Viewpoint from Anthropology and Constructivist Psychology.

PubMed

García Palacios, Mariana; Shabel, Paula; Horn, Axel; Castorina, José Antonio

2018-06-01

Though context has yet to receive an unequivocal definition, it is a concept that frequently appears in research in children's knowledge and its construction. This article examines the scope and meaning of context in genetic psychology and social anthropology in order to better understand the relationship between children's construction of knowledge and the context in which it occurs. Meta-theoretical, theoretical and methodological complexities arise when the concept is analyzed in the two disciplines, and these will also be addressed herein. The fields of anthropology and constructive psychology are both affected by the relationship between the building of knowledge and the social practices surrounding this process. Finally, based on these empirical examinations, the article explores how research methodologies could incorporate the notion of context in research focused on the construction of knowledge.

Cognitive Style and Drafting Performance.

ERIC Educational Resources Information Center

Guster, Dennis

1986-01-01

The relationships between drafting performance and the cognitive style construct of field dependence/field independence are examined. The analysis revealed that the performance of the field-independent individual is likely to be superior to that of the field-dependent student. (Author/CT)

Ontological forms of religious meaning and the conflict between science and religion

NASA Astrophysics Data System (ADS)

Hathcoat, John D.; Habashi, Janette

2013-06-01

Epistemological constructions are central considerations in vivisecting an expressed conflict between science and religion. It is argued that the conflict thesis is only meaningful when examined from a specific socio-historical perspective. The dialectical relation between science and religion should therefore be considered at both a macro and micro level. At the macro level broad changes in the meaning of science and religion occur; whereas at the micro level individuals immersed within particular expressions of these concepts socially construct, re-construct, and appropriate meaning. Specific attention is given to expressions of meaning surrounding sacred texts in this dialectical relation. Two ontological forms of meaning are examined through a qualitative content analysis of 16 interviews with individuals from various religious affiliation and academic attainment. A monistic ontology constructs textual meaning as facts that have the qualities of being both self-evident and certain. Potential tension arises with scientific discourse given empirical evidence may either confirm or conflict with scriptural interpretation. The pluralistic ontology constructs textual meaning with multiple categories, which in turn have the qualities of being mediated by human consciousness and uncertain. The science-religion dichotomy appears to be less susceptible to conflict given the uncertainty embedded in this construction of scriptural meaning. This paper implies that truth as correspondence may not necessitate the conflict thesis.

sl(1|2) Super-Toda Fields

NASA Astrophysics Data System (ADS)

Yang, Zhan-Ying; Xue, Pan-Pan; Zhao, Liu; Shi, Kang-Jie

2008-11-01

Explicit exact solution of supersymmetric Toda fields associated with the Lie superalgebra sl(2|1) is constructed. The approach used is a super extension of Leznov Saveliev algebraic analysis, which is based on a pair of chiral and antichiral Drienfeld Sokolov systems. Though such approach is well understood for Toda field theories associated with ordinary Lie algebras, its super analogue was only successful in the super Liouville case with the underlying Lie superalgebra osp(1|2). The problem lies in that a key step in the construction makes use of the tensor product decomposition of the highest weight representations of the underlying Lie superalgebra, which is not clear until recently. So our construction made in this paper presents a first explicit example of Leznov Saveliev analysis for super Toda systems associated with underlying Lie superalgebras of the rank higher than 1.

What's Worth Talking about? Meaning-Making in Toddler-Initiated Co-Narratives in Preschool

ERIC Educational Resources Information Center

Odegaard, Elin Eriksen

2006-01-01

To elaborate narratives, toddlers are dependent on adult co-construction. Both children and teachers make meaning and learn together. This article examines what themes toddlers introduce in mealtime conversations in preschool. The object of analysis is 39 toddler-initiated co-narratives constructed by toddlers and teachers in 15 videotaped meals…

Negotiation of Meaning and Co-Construction of Knowledge: An Experimental Analysis of Asynchronous Online Instruction

ERIC Educational Resources Information Center

Hull, Darrell M.; Saxon, Terrill F.

2009-01-01

Variations in group co-construction of knowledge and the extent to which participants engaged in negotiating meaning were directly related to instruction. The authors examined social interaction resulting from controlled variation in instruction using a counter-balanced design in two professional development courses for teachers. Both courses were…

Constructs and Events in Verbal Behavior

ERIC Educational Resources Information Center

Fryling, Mitch J.

2013-01-01

Skinner's (1957) analysis of verbal behavior has been the subject of much controversy in recent years. While criticism has historically come from outside the field of behavior analysis, there are now well-articulated arguments against Skinner's analysis of verbal behavior from within the field as well. Recently, advocates of…

The physics of evolution and biodiversity: Old answers to new questions, and more...

NASA Astrophysics Data System (ADS)

Bar-Yam, Yaneer

2013-03-01

In recent years there has been a contentious battle among prominent biologists about the validity of Kin versus Group Selection as models of evolutionary biology. I will show that the controversy is widely misunderstood and is rooted in the mean field basis of RA Fisher's statistical treatment of population biology, which is the origin of the ``gene centered view''-kin selection and inclusive fitness-but is also often used in analysis of group selection. As in statistical physics, symmetry breaking and pattern formation, and their spatial realizations, result in breakdown of the mean field approximation and the widely believed mathematical 'proofs' of the universality of the gene centered view. Our simulation and analysis (http://necsi.edu/research/evoeco/) of the role of this breakdown in spatial ecology, biodiversity, speciation and altruism, suggest there is an entire field of new opportunities to explore in the implications for evolutionary theory. The difference between biodiversity of wildtype populations and narrowly homogeneous laboratory types manifest the self-consistency of theoretical assumptions and laboratory experiments performed under conditions in which the mean field approximation applies. In contrast, the highly diverse natural populations manifest the role of boundaries between types (hybrid zones), speciation by spontaneous clustering, and spatio-temporal dynamics in predator prey systems. Altruism arises in evolving populations due to the spontaneous dynamic group formation and the heritability of environmental conditions created by parents and experienced by offspring (niche construction with symmetry breaking), so that altruists are better able to survive over the long term than selfish variants. Many versions of the mean field approximation that are traditionally used eliminate these spatio-temporal processes, leading to false analytic conclusions about their impossibility. The traditional view of altruism influenced views also of individuals in their relationship to society. In addition to the basic reframing of the origin of altruism, the role of space in evolution has important implications for understanding global dangers today, including pandemics driven by evolution of virulent pathogens that escape death through long-range transportation, and economic or environmental overexploitation when globalization enables exploiters to escape the consequences of their actions.

Effect of Level of Adjunct Questions on Achievement of Field Independent/Field Dependent Learners

ERIC Educational Resources Information Center

Pi-Sui-Hsu; Dwyer, Francis

2004-01-01

Adjunct questions inserted in text requires that an individual is retrieving known concepts and constructing the new meaning. In this process, the individual has to recall the knowledge just studied and locate exactly the location of the information. This study attempts to examine the (a) instructional effects of varied types of adjunct questions…

A Super mKdV Equation: Bosonization, Painlevé Property and Exact Solutions

NASA Astrophysics Data System (ADS)

Ren, Bo; Lou, Sen-Yue

2018-04-01

The symmetry of the fermionic field is obtained by means of the Lax pair of the mKdV equation. A new super mKdV equation is constructed by virtue of the symmetry of the fermionic form. The super mKdV system is changed to a system of coupled bosonic equations with the bosonization approach. The bosonized SmKdV (BSmKdV) equation admits Painlevé property by the standard singularity analysis. The traveling wave solutions of the BSmKdV system are presented by the mapping and deformation method. We also provide other ideas to construct new super integrable systems. Supported by the National Natural Science Foundation of China under Grant Nos. 11775146, 11435005, and 11472177, Shanghai Knowledge Service Platform for Trustworthy Internet of Things under Grant No. ZF1213 and K. C. Wong Magna Fund in Ningbo University

Expanding uses of building information modeling in life-cycle construction projects.

PubMed

Hannele, Kerosuo; Reijo, Miettinen; Tarja, Mäki; Sami, Paavola; Jenni, Korpela; Teija, Rantala

2012-01-01

BIM is targeted at providing information about the entire building and a complete set of design documents and data stored in an integrated database. In this paper, we study the use of BIM in two life-cycle construction projects in Kuopio, Finland during 2011. The analysis of uses of BIM and their main problems will constitute a foundation for an intervention. We will focus on the following questions: (1) How different partners use the composite BIM model? (2) What are the major contradictions or problems in the BIM use? The preliminary findings reported in this study show that BIM has been adopted quite generally to design use but the old ways of collaboration seem to prevail, especially between designers and between designers and building sites. BIM has provided new means and demands for collaboration but expansive uses of BIM for providing new interactive processes across professional fields have not much come true.

Shoreline Position Dynamics: Measurement and Analysis

NASA Astrophysics Data System (ADS)

Barton, C. C.; Rigling, B.; Hunter, N.; Tebbens, S. F.

2012-12-01

The dynamics of sandy shoreline position is a fundamental property of complex beach face processes and is characterized by the power scaling exponent. Spectral analysis was performed on the temporal position of four sandy shorelines extracted from four shore perpendicular profiles each resurveyed approximately seven times per year over twenty-seven years at the Field Research Facility (FRF) by the U.S. Army Corps of Engineers, located at Kitty Hawk, NC. The four shorelines we studied are mean-higher-high-water (MHHW), mean-high-water (MHW), and mean-low-water (MLW) and mean-lower-low-water (MLLW) with elevations of 0.75m, 0.65m, -0.33m, and -0.37m respectively, relative to the NGVD29 geodetic datum. Spectral analysis used to quantify scaling exponents requires data evenly spaced in time. Our previous studies of shoreline dynamics used the Lomb Periodogram method for spectral analysis, which we now show does not return the correct scaling exponent for unevenly spaced data. New to this study is the use of slotted resampling and a linear predictor to construct an evenly spaced data set from an unevenly spaced data set which has been shown with synthetic data to return correct values of the scaling exponents. A periodogram linear regression (PLR) estimate is used to determine the scaling exponent β of the constructed evenly spaced time series. This study shows that sandy shoreline position exhibits nonlinear self-affine dynamics through time. The times series of each of the four shorelines has scaling exponents ranging as follows: MHHW, β = 1.3-2.2; MHW, β = 1.3-2.1; MLW, β = 1.2-1.6; and MLLW, β = 1.2-1.6. Time series with β greater than 1 are non-stationary (mean and standard deviation are not constant through time) and are increasingly internally correlated with increasing β. The range of scaling exponents of the MLW and MLLW shorelines, near β = 1.5, is indicative of a diffusion process. The range of scaling exponents for the MHW and MHHW shorelines indicates spatially variable dynamics higher on the beach face.

Development of a Higher Order Laminate Theory for Modeling Composites with Induced Strain Actuators

NASA Technical Reports Server (NTRS)

Chattopadhyay, Aditi; Seeley, Charles E.

1996-01-01

A refined higher order plate theory is developed to investigate the actuation mechanism of piezoelectric materials surface bonded or embedded in composite laminates. The current analysis uses a displacement field which accurately accounts for transverse shear stresses. Some higher order terms are identified by using the conditions that shear stresses vanish at all free surfaces. Therefore, all boundary conditions for displacements and stresses are satisfied in the present theory. The analysis is implemented using the finite element method which provides a convenient means to construct a numerical solution due to the discrete nature of the actuators. The higher order theory is computationally less expensive than a full three dimensional analysis. The theory is also shown to agree well with published experimental results. Numerical examples are presented for composite plates with thicknesses ranging from thin to very thick.

Profile: a computer program for displaying the geometric relationships of the responses in a factorial design

Treesearch

Stanford L. Arner

1974-01-01

One procedure in analyzing the responses to factors in an experiment is to construct profiles of the means. Profiles are plots of the sample means of each level of one factor at each level of one or more of the other factors in the experiment. The construction of these profiles and tests of hypotheses about the mean responses is called profile analysis. This paper...

MEAN-FIELD MODELING OF AN α{sup 2} DYNAMO COUPLED WITH DIRECT NUMERICAL SIMULATIONS OF RIGIDLY ROTATING CONVECTION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Masada, Youhei; Sano, Takayoshi, E-mail: ymasada@harbor.kobe-u.ac.jp, E-mail: sano@ile.osaka-u.ac.jp

2014-10-10

The mechanism of large-scale dynamos in rigidly rotating stratified convection is explored by direct numerical simulations (DNS) in Cartesian geometry. A mean-field dynamo model is also constructed using turbulent velocity profiles consistently extracted from the corresponding DNS results. By quantitative comparison between the DNS and our mean-field model, it is demonstrated that the oscillatory α{sup 2} dynamo wave, excited and sustained in the convection zone, is responsible for large-scale magnetic activities such as cyclic polarity reversal and spatiotemporal migration. The results provide strong evidence that a nonuniformity of the α-effect, which is a natural outcome of rotating stratified convection, canmore » be an important prerequisite for large-scale stellar dynamos, even without the Ω-effect.« less

Dynamics analysis of SIR epidemic model with correlation coefficients and clustering coefficient in networks.

PubMed

Zhang, Juping; Yang, Chan; Jin, Zhen; Li, Jia

2018-07-14

In this paper, the correlation coefficients between nodes in states are used as dynamic variables, and we construct SIR epidemic dynamic models with correlation coefficients by using the pair approximation method in static networks and dynamic networks, respectively. Considering the clustering coefficient of the network, we analytically investigate the existence and the local asymptotic stability of each equilibrium of these models and derive threshold values for the prevalence of diseases. Additionally, we obtain two equivalent epidemic thresholds in dynamic networks, which are compared with the results of the mean field equations. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Some considerations about aesthetic medicine].

PubMed

Ferreira, Francisco Romão

2010-01-01

In this article, we will discuss some aspects of the construction of the meanings concerning the body from the scientific speech which was modeled based on modern thinking and became the hegemonic thinking of some sectors of the medical field. Meanings attributed to the body bring questions that come from other areas of the social life and those questions will build the aesthetic parameters which will be part of the identity construction, in the relation with the body itself, subjectivity and healthcare. We will describe some moments of the construction of the modern scientific thought and how this thought became hegemonic, influences the common sense, naturalizes identity construction and how dealing with the body, interferes in the healthcare, show a division among some sectors of the biomedicine, reinforce an specific type of medical rationality and makes an epistemic base and principle (theoretical and discursive) to some sectors connected to aesthetic medicine and aesthetic surgeries.

Homeless children: Experiences and meanings of the environments they construct.

PubMed

Forero Pulido, Constanza; Giraldo Pineda, Álvaro; Martínez Hernández, Johana Victoria

2016-04-01

This work sought to learn of the experiences of homeless children and understand the meanings they give to environments they construct within these spaces. The study took place in Medellín, Colombia in 2015. Ours was a qualitative research with ethnographic approach. Non-structured interviews and observations were conducted; a field diary was kept. The street, although a space of public use, is converted by children into their private space; they carry in it almost all their activities and construct two big environments: that of the street that attracts and educates and that of the work that is transitory because it is performed to survive. These children dream with an ideal environment that allows them to live quietly. Children convert the street into a private place where they carry out their daily practices: socializing, working, sleeping, having fun, and relaxing, that is, a place of social construction.

Generalized activity equations for spiking neural network dynamics.

PubMed

Buice, Michael A; Chow, Carson C

2013-01-01

Much progress has been made in uncovering the computational capabilities of spiking neural networks. However, spiking neurons will always be more expensive to simulate compared to rate neurons because of the inherent disparity in time scales-the spike duration time is much shorter than the inter-spike time, which is much shorter than any learning time scale. In numerical analysis, this is a classic stiff problem. Spiking neurons are also much more difficult to study analytically. One possible approach to making spiking networks more tractable is to augment mean field activity models with some information about spiking correlations. For example, such a generalized activity model could carry information about spiking rates and correlations between spikes self-consistently. Here, we will show how this can be accomplished by constructing a complete formal probabilistic description of the network and then expanding around a small parameter such as the inverse of the number of neurons in the network. The mean field theory of the system gives a rate-like description. The first order terms in the perturbation expansion keep track of covariances.

Construction and Validation of a Professional Suitability Scale for Social Work Practice

ERIC Educational Resources Information Center

Tam, Dora M. Y.; Coleman, Heather

2009-01-01

This article reports on the construction and validation of a professional suitability scale, designed for assessing students' suitability for social work practice. Data were collected from 188 field supervisors who provided usable questionnaires, representing a response rate of 74%. Construct validation by exploratory factor analysis identified a…

Designing a valid and reliable Likert attitude scale on the generation of electricity from nuclear power plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calhoun, L.D.

A 15-step flowchart model was applied to the construction of a 20-item long form and a 6-item short form of the scale. Both scales were field-tested on 829 respondents representing a diverse range of subjects: high school juniors and seniors, nuclear engineering students, pre-service teachers, and members of a citizens action group. Both scales are available for immediate use. The 20-item scale appears to be reliable, content valid, and construct valid. Content validity was examined through factor analysis and the use of two separate juries of nuclear experts. Construct validity was examined by application of the known-groups approach. Scale reliabilitymore » and homogeneity were evidenced by a 0.93 coefficient alpha, a range of positive interim correlations of 0.15 to 0.73, and a range of adjusted item-total correlations of 0.46 to 0.80. The 20-item scale also has evaluative quality; means ranged from 2.80 to 3.70. Content validity for the 6-item scale was examined by a jury of nuclear experts. An obtained coefficient alpha of 0.82, a range of interim correlations of 0.51 to 0.72 suggest the scale is reliable and homogeneous. The 6-item short form also appears to have evaluative quality; means ranged from 2.37 to 3.18.« less

Carrier transport and collection in fully depleted semiconductors by a combined action of the space charge field and the field due to electrode voltages

DOEpatents

Rehak, P.; Gatti, E.

1984-02-24

A semiconductor charge transport device and method for making same, characterized by providing a thin semiconductor wafer having rectifying functions on its opposing major surfaces and including a small capacitance ohmic contact, in combination with bias voltage means and associated circuit means for applying a predetermined voltage to effectively deplete the wafer in regions thereof between the rectifying junctions and the ohmic contact. A charge transport device of the invention is usable as a drift chamber, a low capacitance detector, or a charge coupled device each constructed according to the methods of the invention for making such devices. Detectors constructed according to the principles of the invention are characterized by having significantly higher particle position indicating resolution than is attainable with prior art detectors, while at the same time requiring substantially fewer readout channels to realize such high resolution.

Carrier transport and collection in fully depleted semiconductors by a combined action of the space charge field and the field due to electrode voltages

DOEpatents

Rehak, Pavel; Gatti, Emilio

1987-01-01

A semiconductor charge transport device and method for making same, characterized by providing a thin semiconductor wafer having rectifying junctions on its opposing major surfaces and including a small capacitance ohmic contact, in combination with bias voltage means and associated circuit means for applying a predetermined voltage to effectively deplete the wafer in regions thereof between the rectifying junctions and the ohmic contact. A charge transport device of the invention is usable as a drift chamber, a low capacitance detector, or a charge coupled device each constructed according to the methods of the invention for making such devices. Detectors constructed according to the principles of the invention are characterized by having significantly higher particle position indicating resolution than is attainable with prior art detectors, while at the same time requiring substantially fewer readout channels to realize such high resolution.

Carrier transport and collection in fully depleted semiconductors by a combined action of the space charge field and the field due to electrode voltages

DOEpatents

Rehak, P.; Gatti, E.

1987-08-18

A semiconductor charge transport device and method for making same are disclosed, characterized by providing a thin semiconductor wafer having rectifying junctions on its opposing major surfaces and including a small capacitance ohmic contact, in combination with bias voltage means and associated circuit means for applying a predetermined voltage to effectively deplete the wafer in regions thereof between the rectifying junctions and the ohmic contact. A charge transport device of the invention is usable as a drift chamber, a low capacitance detector, or a charge coupled device each constructed according to the methods of the invention for making such devices. Detectors constructed according to the principles of the invention are characterized by having significantly higher particle position indicating resolution than is attainable with prior art detectors, while at the same time requiring substantially fewer readout channels to realize such high resolution. 16 figs.

Constructing the truth: from 'confusion of tongues' to 'constructions in analysis'.

PubMed

Press, Jacques

2006-04-01

The author hypothesizes that the papers Freud wrote in the period 1934-9 constitute a final turning point in his work resulting from an attempt to work through, by means of self-analysis, early traumatic elements reactivated by the conditions of his life in the 1930s. The author emphasizes that the ups and downs of Freud's relationship with Sándor Ferenczi and the mourning which followed his death in 1933 played an important role in this traumatic situation. He suggests that through these last works, Freud pursued a posthumous dialogue with Ferenczi. This working through led Freud, in Moses and monotheism, to an ultimate revision of his theory of trauma, a revision which the author examines in full, in the light of the works of the Egyptologist, Jan Assmann. A new analytical paradigm emerges: that of constructions in analysis developed in the article of the same name. The activity of construction appears as an alternative to the mutual analysis proposed by Ferenczi and is closely bound up with the notion of historical truth. In psychoanalysis, it would mean constructing a historical truth whose anchoring in the material truth of the past is essential, though it should not be confused with it.

"You Focus, I'm Talking": A CHAT Analysis of Mobile Dictionary Use in an Advanced EFL Class

ERIC Educational Resources Information Center

Lilley, Warren; Hardman, Joanne

2017-01-01

This article discusses how students and teachers in an Advanced English as a Foreign Language (EFL) class in Cape Town, South Africa, construct meaning through mobile phones. Drawing on Cultural-Historical Activity Theory (CHAT), mobile phones are viewed as cultural artefacts that learners and teachers engage in the construction of meaning-making…

Visualization and Analysis of a Numerical Simulation of GW150914

NASA Astrophysics Data System (ADS)

Rosato, Nicole

We present a visualization and analysis of a supercomputer simulation displaying the apparent horizons' curvature and radiation emitted from a binary black hole system modeling the LIGO observed signal GW150914. The simulation follows the system from seven orbits prior to merger down to the resultant final Kerr black hole. Apparent horizons are calculated during the simulation with mean curvature data displayed on them. Radiation data was visualized via the real part of the Psi4 component of the Weyl scalars, which were determined using a numerical quasi-Kinnersley method. We also present a comparative study of the differences in using the quasi-Kinnersley and PsiKadelia tetrads to construct Psi4 and the benefits, particularly in the strong field region of a binary black hole system, of using a tetrad in a transverse (Psi1 = Psi3 = 0) frame. The second part of our studies focus on the relationship between the mean curvature displayed on the apparent horizons and the trajectories of the black holes. We notice that prior to merger, for each black hole, the directionality of the mean curvature tracks that of the trajectory with either a positive or negative phase shift between the two curves. Finally, we provide a brief analysis suggesting that the phase shift and the frame dragging effects are likely related.

A Case for the Use of Conceptual Analysis in Science Education Research

ERIC Educational Resources Information Center

Kahn, Sami; Zeidler, Dana L.

2017-01-01

Imprecise constructs abound in science education research in part due to reliance on stipulative definitions that neglect fine distinctions between closely related constructs and overlook important meanings and hidden values embedded in language. Lack of conceptual clarity threatens construct validity, hampers theory development, and prevents…

The "race" concept in smoking: a review of the research on African Americans.

PubMed

King, G

1997-10-01

This paper presents an analysis of the "race" concept as used by researchers who have studied the smoking behavior of African Americans. Most researchers in the field have failed to address the conceptual dimensions and meanings of "race" and accept uncritically the use of the term. This practice is viewed as an impediment in explaining inter- and intra-racial group differences and intervening effectively to reduce consumption of tobacco products. Adopting the majority-minority intergroup relations paradigm, the conceptual and practical meanings of "race" are reviewed by focusing on the history of relations between blacks and tobacco, conceptions of "race," "biology" and cigarette smoking, and the sociological nucleus (e.g. social class, racism and culture) of "race." Genetic or biologic assumptions and meanings of "race" in research on the smoking behavior of African Americans are critically examined. It is argued that "race" is a dynamic social construct reflecting societal transformations in relations between racially classified social groups (RCSGs).

A Second-Order Phase Transition as a Limit of the First-Order Phase Transitions —Coherent Anomalies and Critical Phenomena in the Potts Models—

NASA Astrophysics Data System (ADS)

Katori, Makoto

1988-12-01

A new scheme of the coherent-anomaly method (CAM) is proposed to study critical phenomena in the models for which a mean-field description gives spurious first-order phase transition. A canonical series of mean-field-type approximations are constructed so that the spurious discontinuity should vanish asymptotically as the approximate critical temperature approachs the true value. The true value of the critical exponents β and γ are related to the coherent-anomaly exponents defined among the classical approximations. The formulation is demonstrated in the two-dimensional q-state Potts models for q{=}3 and 4. The result shows that the present method enables us to estimate the critical exponents with high accuracy by using the date of the cluster-mean-field approximations.

Manganese and welding fume exposure and control in construction.

PubMed

Meeker, John D; Susi, Pam; Flynn, Michael R

2007-12-01

Overexposure to welding fume constituents, particularly manganese, is of concern in the construction industry due to the prevalence of welding and the scarcity of engineering controls. The control effectiveness of a commercially available portable local exhaust ventilation (LEV) unit was assessed. It consisted of a portable vacuum and a small bell-shaped hood connected by a flexible 2 inch (50.8 mm) diameter hose, in both experimental and field settings. The experimental testing was done in a semienclosed booth at a pipefitter training facility. Five paired trials of LEV control vs. no control, each approximately 1 hr in duration and conducted during two successive welds of 6 inch (152.4 mm) diameter carbon steel pipe were run in random order. Breathing zone samples were collected outside the welding hood during each trial. In the field scenario, full-shift breathing zone samples were collected from two pipefitters welding carbon steel pipe for a chiller installation on a commercial construction project. Eight days of full-shift sampling were conducted on both workers (n = 16), and the LEV was used by one of the two workers on an alternating basis for 7 of the days. All samples were collected with personal sample pumps calibrated at 2 L/min. Filter cassettes were analyzed for total particulate and manganese concentration by a certified laboratory. In the experimental setting, use of the portable LEV resulted in a 75% reduction in manganese exposure (mean 13 microg/m(3) vs. 51 microg/m(3); p < 0.05) and a 60% reduction in total particulate (mean 0.74 mg/m(3) vs. 1.83 mg/m(3); p < 0.05). In the field setting, LEV use resulted in a 53% reduction in manganese exposure (geometric mean 46 microg/m(3) vs. 97 microg/m(3); p < 0.05) but only a 10% reduction in total particulate (geometric mean 4.5 mg/m(3) vs. 5.0 mg/m(3); p > 0.05). These results demonstrate that LEV use can reduce manganese exposure associated with welding tasks in construction.

Near Infrared Imaging of the Hubble Deep Field with Keck Telescope

NASA Technical Reports Server (NTRS)

Hogg, David W.; Neugebauer, G.; Armus, Lee; Matthews, K.; Pahre, Michael A.; Soifer, B. T.; Weinberger, A. J.

1997-01-01

Two deep K-band (2.2 micrometer) images, with point-source detection limits of K=25.2 mag (one sigma), taken with the Keck Telescope in subfields of the Hubble Deep Field, are presented and analyzed. A sample of objects to K=24 mag is constructed and V(sub 606)- I(sub 814) and I(sub 814)-K colors are measured. By stacking visually selected objects, mean I(sub 814)-K colors can be measured to very faint levels, the mean I(sub 814)-K color is constant with apparent magnitude down to V(sub 606)=28 mag.

Nonequilibrium phase transitions in isotropic Ashkin-Teller model

NASA Astrophysics Data System (ADS)

Akıncı, Ümit

2017-03-01

Dynamic behavior of an isotropic Ashkin-Teller model in the presence of a periodically oscillating magnetic field has been analyzed by means of the mean field approximation. The dynamic equation of motion has been constructed with the help of a Glauber type stochastic process and solved for a square lattice. After defining the possible dynamical phases of the system, phase diagrams have been given and the behavior of the hysteresis loops has been investigated in detail. The hysteresis loop for specific order parameter of isotropic Ashkin-Teller model has been defined and characteristics of this loop in different dynamical phases have been given.

Exploring the Relationship between Beginning Science Teachers' Practices, Institutional Constraints, and Adult Development

NASA Astrophysics Data System (ADS)

Wilcox, Jesse Lee

This year-long study explored how ten teachers--five first year, five second year--acclimated to their new school environment after leaving a master's level university science teacher preparation program known for being highly effective. Furthermore, this study sought to explore if a relationship existed between teachers' understanding and implementation of research-based science teaching practices, the barriers to enacting these practices--known as institutional constraints, and the constructive-developmental theory which explores meaning-making systems known as orders of consciousness. As a naturalistic inquiry mixed methods study, data were collected using both qualitative (e.g., semi-structured interviews, field notes) as well as quantitative methods (e.g., observation protocols, subject/object protocol). These data sources were used to construct participant summaries and a cross-case analysis. The findings from provide evidence that teachers' orders of consciousness might help to explain why understanding research-based science teaching practices are maintained by some new teachers and not others. Additionally, this study found the orders of consciousness of teachers relates to the perceptions of institutional constraints as well as how a teacher chooses to navigate those constraints. Finally, the extent to which teachers implement research-based science teaching practices is related to orders of consciousness. While many studies have focused on what meaning teachers make, this study highlights the importance of considering how teachers make meaning.

Phase-Sensitive Control Of Molecular Dissociation Through Attosecond Pump/Strong-Field Mid-IR Probe Spectroscopy

DTIC Science & Technology

2016-04-15

overarching goal of our program was to develop a novel laser and ion spectroscopy system and to use it for the study of strong-field light-matter...are accelerated into the ion TOF by means of a Fig. I.1 Schematic of ion spectroscopy with two color (EUV + mid-IR) laser fields, as constructed at...Abstract The overarching goal of our program was to develop a novel laser and ion spectroscopy system and to use it for the study of strong-field light

An extended approach for computing the critical properties in the two-and three-dimensional lattices within the effective-field renormalization group method

NASA Astrophysics Data System (ADS)

de Albuquerque, Douglas F.; Santos-Silva, Edimilson; Moreno, N. O.

2009-10-01

In this letter we employing the effective-field renormalization group (EFRG) to study the Ising model with nearest neighbors to obtain the reduced critical temperature and exponents ν for bi- and three-dimensional lattices by increasing cluster scheme by extending recent works. The technique follows up the same strategy of the mean field renormalization group (MFRG) by introducing an alternative way for constructing classical effective-field equations of state takes on rigorous Ising spin identities.

Extending the depth of field in a fixed focus lens using axial colour

NASA Astrophysics Data System (ADS)

Fitzgerald, Niamh; Dainty, Christopher; Goncharov, Alexander V.

2017-11-01

We propose a method of extending the depth of field (EDOF) of conventional lenses for a low cost iris recognition front-facing smartphone camera. Longitudinal chromatic aberration (LCA) can be induced in the lens by means of dual wavelength illumination. The EDOF region is then constructed from the sum of the adjacent depths of field from each wavelength illumination. The lens parameters can be found analytically with paraxial raytracing. The extended depth of field is dependant on the glass chosen and position of the near object point.

Coherent states, quantum gravity, and the Born-Oppenheimer approximation. I. General considerations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stottmeister, Alexander, E-mail: alexander.stottmeister@gravity.fau.de; Thiemann, Thomas, E-mail: thomas.thiemann@gravity.fau.de

2016-06-15

This article, as the first of three, aims at establishing the (time-dependent) Born-Oppenheimer approximation, in the sense of space adiabatic perturbation theory, for quantum systems constructed by techniques of the loop quantum gravity framework, especially the canonical formulation of the latter. The analysis presented here fits into a rather general framework and offers a solution to the problem of applying the usual Born-Oppenheimer ansatz for molecular (or structurally analogous) systems to more general quantum systems (e.g., spin-orbit models) by means of space adiabatic perturbation theory. The proposed solution is applied to a simple, finite dimensional model of interacting spin systems,more » which serves as a non-trivial, minimal model of the aforesaid problem. Furthermore, it is explained how the content of this article and its companion affect the possible extraction of quantum field theory on curved spacetime from loop quantum gravity (including matter fields).« less

Underwater single beam circumferentially scanning detection system using range-gated receiver and adaptive filter

NASA Astrophysics Data System (ADS)

Tan, Yayun; Zhang, He; Zha, Bingting

2017-09-01

Underwater target detection and ranging in seawater are of interest in unmanned underwater vehicles. This study presents an underwater detection system that synchronously scans a collimated laser beam and a narrow field of view to circumferentially detect an underwater target. Hybrid methods of range-gated and variable step-size least mean squares (VSS-LMS) adaptive filter are proposed to suppress water backscattering. The range-gated receiver eliminates the backscattering of near-field water. The VSS-LMS filter extracts the target echo in the remaining backscattering and the constant fraction discriminator timing method is used to improve ranging accuracy. The optimal constant fraction is selected by analysing the jitter noise and slope of the target echo. The prototype of the underwater detection system is constructed and tested in coastal seawater, then the effectiveness of backscattering suppression and high-ranging accuracy is verified through experimental results and analysis discussed in this paper.

Design and construction of a photobioreactor for hydrogen production, including status in the field.

PubMed

Skjånes, Kari; Andersen, Uno; Heidorn, Thorsten; Borgvang, Stig A

Several species of microalgae and phototrophic bacteria are able to produce hydrogen under certain conditions. A range of different photobioreactor systems have been used by different research groups for lab-scale hydrogen production experiments, and some few attempts have been made to upscale the hydrogen production process. Even though a photobioreactor system for hydrogen production does require special construction properties (e.g., hydrogen tight, mixing by other means than bubbling with air), only very few attempts have been made to design photobioreactors specifically for the purpose of hydrogen production. We have constructed a flat panel photobioreactor system that can be used in two modes: either for the cultivation of phototrophic microorganisms (upright and bubbling) or for the production of hydrogen or other anaerobic products (mixing by "rocking motion"). Special emphasis has been taken to avoid any hydrogen leakages, both by means of constructional and material choices. The flat plate photobioreactor system is controlled by a custom-built control system that can log and control temperature, pH, and optical density and additionally log the amount of produced gas and dissolved oxygen concentration. This paper summarizes the status in the field of photobioreactors for hydrogen production and describes in detail the design and construction of a purpose-built flat panel photobioreactor system, optimized for hydrogen production in terms of structural functionality, durability, performance, and selection of materials. The motivations for the choices made during the design process and advantages/disadvantages of previous designs are discussed.

Trial wave functions for ring-trapped ions and neutral atoms: Microscopic description of the quantum space-time crystal

NASA Astrophysics Data System (ADS)

Yannouleas, Constantine; Landman, Uzi

2017-10-01

A constructive theoretical platform for the description of quantum space-time crystals uncovers for N interacting and ring-confined rotating particles the existence of low-lying states with proper space-time crystal behavior. The construction of the corresponding many-body trial wave functions proceeds first via symmetry breaking at the mean-field level followed by symmetry restoration using projection techniques. The ensuing correlated many-body wave functions are stationary states and preserve the rotational symmetries, and at the same time they reflect the point-group symmetries of the mean-field crystals. This behavior results in the emergence of sequences of select magic angular momenta Lm. For angular-momenta away from the magic values, the trial functions vanish. Symmetry breaking beyond the mean-field level can be induced by superpositions of such good-Lm many-body stationary states. We show that superposing a pair of adjacent magic angular momenta states leads to formation of special broken-symmetry states exhibiting quantum space-time-crystal behavior. In particular, the corresponding particle densities rotate around the ring, showing undamped and nondispersed periodic crystalline evolution in both space and time. The experimental synthesis of such quantum space-time-crystal wave packets is predicted to be favored in the vicinity of ground-state energy crossings of the Aharonov-Bohm-type spectra accessed via an externally applied, natural or synthetic, magnetic field. These results are illustrated here for Coulomb-repelling fermionic ions and for a lump of contact-interaction attracting bosons.

Tropical cyclone intensities from satellite microwave data

NASA Technical Reports Server (NTRS)

Vonderhaar, T. H.; Kidder, S. Q.

1980-01-01

Radial profiles of mean 1000 mb to 250 mb temperature from the Nimbus 6 scanning microwave spectrometer (SCAMS) were constructed around eight intensifying tropical storms in the western Pacific. Seven storms showed distinct inward temperature gradients required for intensification; the eighth displayed no inward gradient and was decaying 24 hours later. The possibility that satellite data might be used to forecast tropical cyclone turning motion was investigated using estimates obtained from Nimbus 6 SCAMS data tapes of the mean 1000 mb to 250 mb temperature field around eleven tropical storms in 1975. Analysis of these data show that for turning storms, in all but one case, the turn was signaled 24 hours in advance by a significant temperature gradient perpendicular to the storm's path, at a distance of 9 deg to 13 deg in front of the storm. A thresholding technique was applied to the North Central U.S. during the summer to estimate precipitation frequency. except

Spotting Incorrect Rules in Signed-Number Arithmetic by the Individual Consistency Index.

DTIC Science & Technology

1981-08-01

meaning of dimensionality of achievement data. It also shows the importance of construct validity, even in criterion referenced testing of the cognitive ... aspect of performance, and that the traditional means of item analysis that are based on taking the variances of binary scores and content analysis

MAGNETOHYDRODYNAMIC SIMULATION-DRIVEN KINEMATIC MEAN FIELD MODEL OF THE SOLAR CYCLE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simard, Corinne; Charbonneau, Paul; Bouchat, Amelie, E-mail: corinne@astro.umontreal.ca, E-mail: paulchar@astro.umontreal.ca, E-mail: amelie.bouchat@mail.mcgill.ca

We construct a series of kinematic axisymmetric mean-field dynamo models operating in the {alpha}{Omega}, {alpha}{sup 2}{Omega} and {alpha}{sup 2} regimes, all using the full {alpha}-tensor extracted from a global magnetohydrodynamical simulation of solar convection producing large-scale magnetic fields undergoing solar-like cyclic polarity reversals. We also include an internal differential rotation profile produced in a purely hydrodynamical parent simulation of solar convection, and a simple meridional flow profile described by a single cell per meridional quadrant. An {alpha}{sup 2}{Omega} mean-field model, presumably closest to the mode of dynamo action characterizing the MHD simulation, produces a spatiotemporal evolution of magnetic fields thatmore » share some striking similarities with the zonally-averaged toroidal component extracted from the simulation. Comparison with {alpha}{sup 2} and {alpha}{Omega} mean-field models operating in the same parameter regimes indicates that much of the complexity observed in the spatiotemporal evolution of the large-scale magnetic field in the simulation can be traced to the turbulent electromotive force. Oscillating {alpha}{sup 2} solutions are readily produced, and show some similarities with the observed solar cycle, including a deep-seated toroidal component concentrated at low latitudes and migrating equatorward in the course of the solar cycle. Various numerical experiments performed using the mean-field models reveal that turbulent pumping plays an important role in setting the global characteristics of the magnetic cycles.« less

Hamiltonian replica exchange combined with elastic network analysis to enhance global domain motions in atomistic molecular dynamics simulations.

PubMed

Ostermeir, Katja; Zacharias, Martin

2014-12-01

Coarse-grained elastic network models (ENM) of proteins offer a low-resolution representation of protein dynamics and directions of global mobility. A Hamiltonian-replica exchange molecular dynamics (H-REMD) approach has been developed that combines information extracted from an ENM analysis with atomistic explicit solvent MD simulations. Based on a set of centers representing rigid segments (centroids) of a protein, a distance-dependent biasing potential is constructed by means of an ENM analysis to promote and guide centroid/domain rearrangements. The biasing potentials are added with different magnitude to the force field description of the MD simulation along the replicas with one reference replica under the control of the original force field. The magnitude and the form of the biasing potentials are adapted during the simulation based on the average sampled conformation to reach a near constant biasing in each replica after equilibration. This allows for canonical sampling of conformational states in each replica. The application of the methodology to a two-domain segment of the glycoprotein 130 and to the protein cyanovirin-N indicates significantly enhanced global domain motions and improved conformational sampling compared with conventional MD simulations. © 2014 Wiley Periodicals, Inc.

Beyond mean-field approximations for accurate and computationally efficient models of on-lattice chemical kinetics

NASA Astrophysics Data System (ADS)

Pineda, M.; Stamatakis, M.

2017-07-01

Modeling the kinetics of surface catalyzed reactions is essential for the design of reactors and chemical processes. The majority of microkinetic models employ mean-field approximations, which lead to an approximate description of catalytic kinetics by assuming spatially uncorrelated adsorbates. On the other hand, kinetic Monte Carlo (KMC) methods provide a discrete-space continuous-time stochastic formulation that enables an accurate treatment of spatial correlations in the adlayer, but at a significant computation cost. In this work, we use the so-called cluster mean-field approach to develop higher order approximations that systematically increase the accuracy of kinetic models by treating spatial correlations at a progressively higher level of detail. We further demonstrate our approach on a reduced model for NO oxidation incorporating first nearest-neighbor lateral interactions and construct a sequence of approximations of increasingly higher accuracy, which we compare with KMC and mean-field. The latter is found to perform rather poorly, overestimating the turnover frequency by several orders of magnitude for this system. On the other hand, our approximations, while more computationally intense than the traditional mean-field treatment, still achieve tremendous computational savings compared to KMC simulations, thereby opening the way for employing them in multiscale modeling frameworks.

Advanced functional network analysis in the geosciences: The pyunicorn package

NASA Astrophysics Data System (ADS)

Donges, Jonathan F.; Heitzig, Jobst; Runge, Jakob; Schultz, Hanna C. H.; Wiedermann, Marc; Zech, Alraune; Feldhoff, Jan; Rheinwalt, Aljoscha; Kutza, Hannes; Radebach, Alexander; Marwan, Norbert; Kurths, Jürgen

2013-04-01

Functional networks are a powerful tool for analyzing large geoscientific datasets such as global fields of climate time series originating from observations or model simulations. pyunicorn (pythonic unified complex network and recurrence analysis toolbox) is an open-source, fully object-oriented and easily parallelizable package written in the language Python. It allows for constructing functional networks (aka climate networks) representing the structure of statistical interrelationships in large datasets and, subsequently, investigating this structure using advanced methods of complex network theory such as measures for networks of interacting networks, node-weighted statistics or network surrogates. Additionally, pyunicorn allows to study the complex dynamics of geoscientific systems as recorded by time series by means of recurrence networks and visibility graphs. The range of possible applications of the package is outlined drawing on several examples from climatology.

Design and construction of an Offner spectrometer based on geometrical analysis of ring fields.

PubMed

Kim, Seo Hyun; Kong, Hong Jin; Lee, Jong Ung; Lee, Jun Ho; Lee, Jai Hoon

2014-08-01

A method to obtain an aberration-corrected Offner spectrometer without ray obstruction is proposed. A new, more efficient spectrometer optics design is suggested in order to increase its spectral resolution. The derivation of a new ring equation to eliminate ray obstruction is based on geometrical analysis of the ring fields for various numerical apertures. The analytical design applying this equation was demonstrated using the optical design software Code V in order to manufacture a spectrometer working in wavelengths of 900-1700 nm. The simulation results show that the new concept offers an analytical initial design taking the least time of calculation. The simulated spectrometer exhibited a modulation transfer function over 80% at Nyquist frequency, root-mean-square spot diameters under 8.6 μm, and a spectral resolution of 3.2 nm. The final design and its realization of a high resolution Offner spectrometer was demonstrated based on the simulation result. The equation and analytical design procedure shown here can be applied to most Offner systems regardless of the wavelength range.

Does higher screw density improve radiographic and clinical outcomes in adolescent idiopathic scoliosis? A systematic review and pooled analysis.

PubMed

Luo, Ming; Wang, Wengang; Shen, Mingkui; Luo, Xin; Xia, Lei

2017-04-01

OBJECTIVE The radiographic and clinical outcomes of low-density (LD) versus high-density (HD) screw constructs in patients with adolescent idiopathic scoliosis (AIS) treated with all-pedicle screw constructs are still controversial. A systematic review and pooled analysis were performed to compare radiographic, perioperative, and quality-of-life (QOL) outcomes and complications in patients with moderate AIS treated with LD or HD screw constructs. METHODS The MEDLINE, Embase, and Web of Science databases were searched for English-language articles addressing LD versus HD screw constructs in AIS patients treated with all-pedicle screw constructs. The division of LD and HD groups was based on relative screw density and screw techniques. This systematic analysis strictly followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, and all articles included in the analysis met the criteria specified in the guidelines. Two reviewers independently assessed the quality of the studies using the Newcastle-Ottawa Scale. Date on radiographic, perioperative, and QOL outcomes and complications were extracted from the included studies. RESULTS Twelve studies, involving a total of 827 patients (480 treated with LD constructs, 347 with HD), were analyzed-1 randomized controlled trial, 1 quasi-randomized controlled trial, and 10 retrospective studies. The patients' age at surgery, preoperative Cobb angle of the major curve, amount of thoracic kyphosis, and major curve flexibility were reasonably distributed, and no statistically significant differences were found. Regarding the outcomes at most recent follow-up, there were no significant differences in the Cobb angle of the major curve (mean difference 0.96°, 95% CI -0.06° to 1.98°, p = 0.06, I 2 = 1%), major curve correction (mean difference -0.72%, 95% CI -2.96% to 1.52%, p = 0.53, I 2 = 0%), thoracic kyphosis (mean difference -1.67°, 95% CI -4.59° to 1.25°, p = 0.26, I 2 = 79%), complications (odds ratio [OR] 0.66, 95% CI 0.31-1.42, p = 0.29, I 2 = 0%), and QOL outcomes. Reduced operative time (mean difference -48.56 minutes, 95% CI -82.69 to -14.43 minutes, p = 0.005, I 2 = 87%), blood loss (mean difference -77.85 ml, 95% CI -153.10 to -2.60 ml, p = 0.04, I 2 = 0%), and hospital charges (mean difference -$5.92K, 95% CI -$6.59K to -$5.26K, p < 0.00001, I 2 = 0%) were found in the LD group, compared with the HD group. CONCLUSIONS LD and HD screw constructs are both associated with satisfactory radiographic and QOL outcomes with few complications. This study supports the use of LD screw constructs for the treatment of moderate AIS, because they resulted in reduced operative time, blood loss, and hospital charges while maintaining radiographic and QOL outcomes and complication rates similar to those achieved with HD screw constructs.

[Primary healthcare and the construction of meanings for oral health: a social constructionist interpretation of discourses by the elderly].

PubMed

Bulgarelli, Alexandre Favero; Lorenzi, Carla Guanáes; Silva, Rosalina Carvalho da; Mestriner, Soraya Fernandes; Villa, Teresa Cristina Scatena; Pinto, Ione Carvalho

2012-08-01

Dentistry is nowadays open to new ideas about the constructions of meanings for oral health. This openness tallies with the social production of health and shows the need to contextualize the social, historical and sundry knowledge in the development of oral health for different communities. The scope of this research is to build meanings for oral health with a group of elderly people. With this in mind, we propose an approximation between the discourses of the elderly on oral health and the Social Constructionist discourse. Thus, we interviewed 14 elderly people registered with a Family Health Unit in Ribeirão Preto in the State of São Paulo in the first semester of 2010. This enabled us to identify two Interpretative Repertoires with the use of Discourse Analysis, which showed the relationship between: 1 - Lack of dental information and assistance in childhood; and 2 - Primary Healthcare constructing meaning for oral health. We concluded that Social Constructionism assists epistemologically for the construction of meaning for oral health and that Primary Healthcare is essential for valuing healthcare for the construction of meaning for oral health on the part of the elderly by fostering conditions for self care and healthy attitudes.

Direct construction of mesoscopic models from microscopic simulations

NASA Astrophysics Data System (ADS)

Lei, Huan; Caswell, Bruce; Karniadakis, George Em

2010-02-01

Starting from microscopic molecular-dynamics (MD) simulations of constrained Lennard-Jones (LJ) clusters (with constant radius of gyration Rg ), we construct two mesoscopic models [Langevin dynamics and dissipative particle dynamics (DPD)] by coarse graining the LJ clusters into single particles. Both static and dynamic properties of the coarse-grained models are investigated and compared with the MD results. The effective mean force field is computed as a function of the intercluster distance, and the corresponding potential scales linearly with the number of particles per cluster and the temperature. We verify that the mean force field can reproduce the equation of state of the atomistic systems within a wide density range but the radial distribution function only within the dilute and the semidilute regime. The friction force coefficients for both models are computed directly from the time-correlation function of the random force field of the microscopic system. For high density or a large cluster size the friction force is overestimated and the diffusivity underestimated due to the omission of many-body effects as a result of the assumed pairwise form of the coarse-grained force field. When the many-body effect is not as pronounced (e.g., smaller Rg or semidilute system), the DPD model can reproduce the dynamic properties of the MD system.

Mass-imbalanced Hubbard model in optical lattice with site-dependent interactions

NASA Astrophysics Data System (ADS)

Le, Duc-Anh; Tran, Thi-Thu-Trang; Hoang, Anh-Tuan; Nguyen, Toan-Thang; Tran, Minh-Tien

2018-03-01

We study the half-filled mass-imbalanced Hubbard model with spatially alternating interactions on an optical bipartite lattice by means of the dynamical mean-field theory. The Mott transition is investigated via the spin-dependent density of states and double occupancies. The phase diagrams for the homogeneous phases at zero temperature are constructed numerically. The boundary between metallic and insulating phases at zero temperature is analytically derived within the dynamical mean field theory using the equation of motion approach as the impurity solver. We found that the metallic region is reduced with increasing interaction anisotropy or mass imbalance. Our results are closely relevant to current researches in ultracold fermion experiments and can be verified through experimental observations.

Mean Field Limits for Interacting Diffusions in a Two-Scale Potential

NASA Astrophysics Data System (ADS)

Gomes, S. N.; Pavliotis, G. A.

2018-06-01

In this paper, we study the combined mean field and homogenization limits for a system of weakly interacting diffusions moving in a two-scale, locally periodic confining potential, of the form considered in Duncan et al. (Brownian motion in an N-scale periodic potential, arXiv:1605.05854, 2016b). We show that, although the mean field and homogenization limits commute for finite times, they do not, in general, commute in the long time limit. In particular, the bifurcation diagrams for the stationary states can be different depending on the order with which we take the two limits. Furthermore, we construct the bifurcation diagram for the stationary McKean-Vlasov equation in a two-scale potential, before passing to the homogenization limit, and we analyze the effect of the multiple local minima in the confining potential on the number and the stability of stationary solutions.

Pre-Columbian Agriculture: Construction history of raised fields in Bermeo, in the Bolivian Lowlands

NASA Astrophysics Data System (ADS)

Rodrigues, Leonor; Fehr, Seraina; Lombardo, Umberto; Veit, Heinz

2013-04-01

Since the beginning of the 1960s, research in the Amazon has revealed that in Pre-Columbian times, landscapes that were viewed as challenging living environments were nevertheless altered in several ways. Raised fields agriculture is one of the most impressive phenomena that can be found in South-eastern Amazonia. Pre-Columbian raised fields are earth platforms of differing shape and dimension that are elevated above the landscape's natural surface. The Llanos de Moxos, situated in the Bolivian Lowlands is one of the areas with the highest density of raised fields. In spite of the high interest in raised field agriculture, very few field-based investigations have been performed. As a result, there remains little explanation as to how they were constructed, managed or for what time frame they were in use. Recently, more detailed investigations have been performed on raised fields located in the indigenous community of Bermeo, in the vicinity of San Ignacio de Moxos. Combined data from fieldwork and laboratory analysis including particle size distribution, thin section micromorphology and radiocarbon analyses as well as optically stimulated luminescence analysis has given an insight into the history of their construction. Applied to the Bolivian Lowlands, the current study provides for the first time data showing aspects of the Pre-Columbian management of the raised fields, and a chronological sequence of utilization and abandonment of these fields. Radiocarbon dating has shown that the raised fields had been in use since as early as 900 AD. Two distinct paleosols identified in the field sequence point to the existence of two separate prolonged soil formation periods. The paleosols are characterized by initial stages of Bt-horizons. Each soil sequence indicates therefore a particular stable period of the field during which no new earth was heaped up. This suggests that contrary to the well supported theory that raised fields were managed through continuous accumulation of sediments transported from the canal to the field, the raised fields were more likely built during large, single construction events.

Directional Analysis of the Storm Surge from Hurricane Sandy 2012, with Applications to Charleston, New Orleans, and the Philippines

PubMed Central

Drews, Carl; Galarneau, Thomas J.

2015-01-01

Hurricane Sandy in late October 2012 drove before it a storm surge that rose to 4.28 meters above mean lower low water at The Battery in lower Manhattan, and flooded the Hugh L. Carey automobile tunnel between Brooklyn and The Battery. This study examines the surge event in New York Harbor using the Weather Research and Forecasting (WRF) atmospheric model and the Coupled-Ocean-Atmosphere-Wave- Sediment Transport / Regional Ocean Modeling System (COAWST/ROMS). We present a new technique using directional analysis to calculate and display maps of a coastline's potential for storm surge; these maps are constructed from wind fields blowing from eight fixed compass directions. This analysis approximates the surge observed during Hurricane Sandy. The directional analysis is then applied to surge events at Charleston, South Carolina, New Orleans, Louisiana, and Tacloban City, the Philippines. Emergency managers could use these directional maps to prepare their cities for an approaching storm, on planning horizons from days to years. PMID:25822480

Directional analysis of the storm surge from Hurricane Sandy 2012, with applications to Charleston, New Orleans, and the Philippines.

PubMed

Drews, Carl; Galarneau, Thomas J

2015-01-01

Hurricane Sandy in late October 2012 drove before it a storm surge that rose to 4.28 meters above mean lower low water at The Battery in lower Manhattan, and flooded the Hugh L. Carey automobile tunnel between Brooklyn and The Battery. This study examines the surge event in New York Harbor using the Weather Research and Forecasting (WRF) atmospheric model and the Coupled-Ocean-Atmosphere-Wave- Sediment Transport/Regional Ocean Modeling System (COAWST/ROMS). We present a new technique using directional analysis to calculate and display maps of a coastline's potential for storm surge; these maps are constructed from wind fields blowing from eight fixed compass directions. This analysis approximates the surge observed during Hurricane Sandy. The directional analysis is then applied to surge events at Charleston, South Carolina, New Orleans, Louisiana, and Tacloban City, the Philippines. Emergency managers could use these directional maps to prepare their cities for an approaching storm, on planning horizons from days to years.

The interaction of assessment format and sex in assessing the knowledge structure coherence of middle school students' understanding of the concept of force

NASA Astrophysics Data System (ADS)

Schleigh, Sharon

This study focuses on the impact of assessment format on the identification of students' ideas surrounding the concept of force and the consistency with which students apply those ideas across contexts. It is in response to the debate in conceptual change literature regarding students' knowledge structure coherence. Empirical studies in this field typically rely on an interview assessment format. The current study examined the potential of a constructed response assessment format as another possible instrument for data collection involving larger sample populations. The current study specifically compared how the two assessment formats (constructed response and interview assessment) assessed 45 students in the ninth grade in a single school in Arizona. The analysis explored possible biases and interactions by sex, order of assessment, and preference for assessment format because the literature suggests that these factors may potentially affect the performance and coding of assessments. Although small differences between the two assessments were found, the differences were not statistically significant overall or for any subgroup. More specifically, there were no apparent significant biases in the two formats with regard to one another and student sex. However it was found that girls are more likely to express multiple-best match meanings than boys in both assessments. This may be an influence in the diversity found in previous studies concerning students' knowledge structures. These findings suggest that the constructed response format could be administered on a larger scale to assist in the identification of factors contributing to the differences in findings across prior studies in this field. Additionally, these results suggest the potential of this constructed response format for helping teachers conduct formative assessments to guide instructional decisions.

Pesticide mitigation capacities of constructed wetlands

Treesearch

Matthew T. Moore; Charles M. Cooper; Sammie Smith; John H. Rodgers

2000-01-01

This research focused on using constructed wetlands along field perimeters to buffer receiving water against potential effects of pesticides associated with storm runoff. The current study incorporated wetland mesocosm sampling following simulated runoff events using chlorpyrifos, atrazine, and metolachlor. Through this data collection and simple model analysis,...

The Construction of an Embankment with Frozen Soil.

DTIC Science & Technology

1980-05-01

Idewlrty by block numlbe) Inls paper presents the construction procedure, data and analysis from an experimental field program to determine the rippability ...finite element computer solution. Also the frozen chunks, produced in the ripping operation, were analyzed to determine the rippability of the frozen

Methods for visualising active microbial benzene degraders in in situ microcosms.

PubMed

Schurig, Christian; Mueller, Carsten W; Höschen, Carmen; Prager, Andrea; Kothe, Erika; Beck, Henrike; Miltner, Anja; Kästner, Matthias

2015-01-01

Natural attenuation maybe a cost-efficient option for bioremediation of contaminated sites but requires knowledge about the activity of degrading microbes under in situ conditions. In order to link microbial activity to the spatial distribution of contaminant degraders, we combined the recently improved in situ microcosm approach, so-called 'direct-push bacterial trap' (DP-BACTRAP), with nano-scale secondary ion mass spectrometry (NanoSIMS) analysis on samples from contaminated constructed wetlands. This approach is based on initially sterile microcosms amended with (13)C-labelled benzene as a source of carbon and energy for microorganisms. The microcosms were introduced directly in the constructed wetland, where they were colonised by indigenous microorganisms from the sediment. After incubation in the field, the samples were analysed by NanoSIMS, scanning electron microscopy (SEM) and fluorescence microscopy in order to visualise (13)C-labelled microbial biomass on undisturbed samples from the microcosms. With the approach developed, we successfully visualised benzene-degrading microbes on solid materials with high surface area by means of NanoSIMS. Moreover, we could demonstrate the feasibility of NanoSIMS analysis of unembedded porous media with a highly complex topography, which was frequently reasoned to not lead to sufficient results.

Unified functional network and nonlinear time series analysis for complex systems science: The pyunicorn package

NASA Astrophysics Data System (ADS)

Donges, Jonathan; Heitzig, Jobst; Beronov, Boyan; Wiedermann, Marc; Runge, Jakob; Feng, Qing Yi; Tupikina, Liubov; Stolbova, Veronika; Donner, Reik; Marwan, Norbert; Dijkstra, Henk; Kurths, Jürgen

2016-04-01

We introduce the pyunicorn (Pythonic unified complex network and recurrence analysis toolbox) open source software package for applying and combining modern methods of data analysis and modeling from complex network theory and nonlinear time series analysis. pyunicorn is a fully object-oriented and easily parallelizable package written in the language Python. It allows for the construction of functional networks such as climate networks in climatology or functional brain networks in neuroscience representing the structure of statistical interrelationships in large data sets of time series and, subsequently, investigating this structure using advanced methods of complex network theory such as measures and models for spatial networks, networks of interacting networks, node-weighted statistics, or network surrogates. Additionally, pyunicorn provides insights into the nonlinear dynamics of complex systems as recorded in uni- and multivariate time series from a non-traditional perspective by means of recurrence quantification analysis, recurrence networks, visibility graphs, and construction of surrogate time series. The range of possible applications of the library is outlined, drawing on several examples mainly from the field of climatology. pyunicorn is available online at https://github.com/pik-copan/pyunicorn. Reference: J.F. Donges, J. Heitzig, B. Beronov, M. Wiedermann, J. Runge, Q.-Y. Feng, L. Tupikina, V. Stolbova, R.V. Donner, N. Marwan, H.A. Dijkstra, and J. Kurths, Unified functional network and nonlinear time series analysis for complex systems science: The pyunicorn package, Chaos 25, 113101 (2015), DOI: 10.1063/1.4934554, Preprint: arxiv.org:1507.01571 [physics.data-an].

Simple recursion relations for general field theories

DOE PAGES

Cheung, Clifford; Shen, Chia -Hsien; Trnka, Jaroslav

2015-06-17

On-shell methods offer an alternative definition of quantum field theory at tree-level, replacing Feynman diagrams with recursion relations and interaction vertices with a handful of seed scattering amplitudes. In this paper we determine the simplest recursion relations needed to construct a general four-dimensional quantum field theory of massless particles. For this purpose we define a covering space of recursion relations which naturally generalizes all existing constructions, including those of BCFW and Risager. The validity of each recursion relation hinges on the large momentum behavior of an n-point scattering amplitude under an m-line momentum shift, which we determine solely from dimensionalmore » analysis, Lorentz invariance, and locality. We show that all amplitudes in a renormalizable theory are 5-line constructible. Amplitudes are 3-line constructible if an external particle carries spin or if the scalars in the theory carry equal charge under a global or gauge symmetry. Remarkably, this implies the 3-line constructibility of all gauge theories with fermions and complex scalars in arbitrary representations, all supersymmetric theories, and the standard model. Moreover, all amplitudes in non-renormalizable theories without derivative interactions are constructible; with derivative interactions, a subset of amplitudes is constructible. We illustrate our results with examples from both renormalizable and non-renormalizable theories. In conclusion, our study demonstrates both the power and limitations of recursion relations as a self-contained formulation of quantum field theory.« less

EMPCA and Cluster Analysis of Quasar Spectra: Construction and Application to Simulated Spectra

NASA Astrophysics Data System (ADS)

Marrs, Adam; Leighly, Karen; Wagner, Cassidy; Macinnis, Francis

2017-01-01

Quasars have complex spectra with emission lines influenced by many factors. Therefore, to fully describe the spectrum requires specification of a large number of parameters, such as line equivalent width, blueshift, and ratios. Principal Component Analysis (PCA) aims to construct eigenvectors-or principal components-from the data with the goal of finding a few key parameters that can be used to predict the rest of the spectrum fairly well. Analysis of simulated quasar spectra was used to verify and justify our modified application of PCA.We used a variant of PCA called Weighted Expectation Maximization PCA (EMPCA; Bailey 2012) along with k-means cluster analysis to analyze simulated quasar spectra. Our approach combines both analytical methods to address two known problems with classical PCA. EMPCA uses weights to account for uncertainty and missing points in the spectra. K-means groups similar spectra together to address the nonlinearity of quasar spectra, specifically variance in blueshifts and widths of the emission lines.In producing and analyzing simulations, we first tested the effects of varying equivalent widths and blueshifts on the derived principal components, and explored the differences between standard PCA and EMPCA. We also tested the effects of varying signal-to-noise ratio. Next we used the results of fits to composite quasar spectra (see accompanying poster by Wagner et al.) to construct a set of realistic simulated spectra, and subjected those spectra to the EMPCA /k-means analysis. We concluded that our approach was validated when we found that the mean spectra from our k-means clusters derived from PCA projection coefficients reproduced the trends observed in the composite spectra.Furthermore, our method needed only two eigenvectors to identify both sets of correlations used to construct the simulations, as well as indicating the linear and nonlinear segments. Comparing this to regular PCA, which can require a dozen or more components, or to direct spectral analysis that may need measurement of 20 fit parameters, shows why the dual application of these two techniques is such a powerful tool.

Employability Deconstructed: Perceptions of Bologna Stakeholders

ERIC Educational Resources Information Center

Sin, Cristina; Neave, Guy

2016-01-01

The paper analyses employability as a floating signifier--a construct that accommodates different and often contending meanings. A preliminary analysis of scholarly literature identifies two opposed interpretations of employability--an individual responsibility versus a comprehensive context-aware construct. These are subsequently applied to the…

Incorporation of wavelength selective devices into waveguides with applications to a miniature spectrometer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stallard, B. R.; Kaushik, S.; Hadley, G. R.

1996-02-01

This report pertains to a Laboratory Directed Research and Development project which was funded for FY94 and FY95. The goal was to develop building blocks for small, cheap sensors that use optical spectroscopy as a means of detecting chemical analytes. Such sensors can have an impact on a wide variety of technologies, such as: industrial process control, environmental monitors, chemical analysis in medicine, and automotive monitors. We describe work in fabricating and demonstrating a waveguide/grating device that can serve as the wavelength dispersive component in a miniature spectrometer. Also, we describe the invention and modeling of a new way tomore » construct an array of optical interference filters using sub-wavelength lithography to tune the index of refraction of a fixed Fabry-Perot cavity. Next we describe progress in more efficiently calculating the fields in grating devices. Finally we present the invention of a new type of near field optical probe, applicable to scanning microscopy or optical data storage, which is based on a circular grating constructed in a waveguide. This result diverges from the original goal of the project but is quite significant in that it promises to increase the data storage capacity of CD-ROMs by 10 times.« less

Classification of high resolution remote sensing image based on geo-ontology and conditional random fields

NASA Astrophysics Data System (ADS)

Hong, Liang

2013-10-01

The availability of high spatial resolution remote sensing data provides new opportunities for urban land-cover classification. More geometric details can be observed in the high resolution remote sensing image, Also Ground objects in the high resolution remote sensing image have displayed rich texture, structure, shape and hierarchical semantic characters. More landscape elements are represented by a small group of pixels. Recently years, the an object-based remote sensing analysis methodology is widely accepted and applied in high resolution remote sensing image processing. The classification method based on Geo-ontology and conditional random fields is presented in this paper. The proposed method is made up of four blocks: (1) the hierarchical ground objects semantic framework is constructed based on geoontology; (2) segmentation by mean-shift algorithm, which image objects are generated. And the mean-shift method is to get boundary preserved and spectrally homogeneous over-segmentation regions ;(3) the relations between the hierarchical ground objects semantic and over-segmentation regions are defined based on conditional random fields framework ;(4) the hierarchical classification results are obtained based on geo-ontology and conditional random fields. Finally, high-resolution remote sensed image data -GeoEye, is used to testify the performance of the presented method. And the experimental results have shown the superiority of this method to the eCognition method both on the effectively and accuracy, which implies it is suitable for the classification of high resolution remote sensing image.

Role of pseudo-turbulent stresses in shocked particle clouds and construction of surrogate models for closure

NASA Astrophysics Data System (ADS)

Sen, O.; Gaul, N. J.; Davis, S.; Choi, K. K.; Jacobs, G.; Udaykumar, H. S.

2018-05-01

Macroscale models of shock-particle interactions require closure terms for unresolved solid-fluid momentum and energy transfer. These comprise the effects of mean as well as fluctuating fluid-phase velocity fields in the particle cloud. Mean drag and Reynolds stress equivalent terms (also known as pseudo-turbulent terms) appear in the macroscale equations. Closure laws for the pseudo-turbulent terms are constructed in this work from ensembles of high-fidelity mesoscale simulations. The computations are performed over a wide range of Mach numbers ( M) and particle volume fractions (φ ) and are used to explicitly compute the pseudo-turbulent stresses from the Favre average of the velocity fluctuations in the flow field. The computed stresses are then used as inputs to a Modified Bayesian Kriging method to generate surrogate models. The surrogates can be used as closure models for the pseudo-turbulent terms in macroscale computations of shock-particle interactions. It is found that the kinetic energy associated with the velocity fluctuations is comparable to that of the mean flow—especially for increasing M and φ . This work is a first attempt to quantify and evaluate the effect of velocity fluctuations for problems of shock-particle interactions.

Role of pseudo-turbulent stresses in shocked particle clouds and construction of surrogate models for closure

NASA Astrophysics Data System (ADS)

Sen, O.; Gaul, N. J.; Davis, S.; Choi, K. K.; Jacobs, G.; Udaykumar, H. S.

2018-02-01

Macroscale models of shock-particle interactions require closure terms for unresolved solid-fluid momentum and energy transfer. These comprise the effects of mean as well as fluctuating fluid-phase velocity fields in the particle cloud. Mean drag and Reynolds stress equivalent terms (also known as pseudo-turbulent terms) appear in the macroscale equations. Closure laws for the pseudo-turbulent terms are constructed in this work from ensembles of high-fidelity mesoscale simulations. The computations are performed over a wide range of Mach numbers (M) and particle volume fractions (φ ) and are used to explicitly compute the pseudo-turbulent stresses from the Favre average of the velocity fluctuations in the flow field. The computed stresses are then used as inputs to a Modified Bayesian Kriging method to generate surrogate models. The surrogates can be used as closure models for the pseudo-turbulent terms in macroscale computations of shock-particle interactions. It is found that the kinetic energy associated with the velocity fluctuations is comparable to that of the mean flow—especially for increasing M and φ . This work is a first attempt to quantify and evaluate the effect of velocity fluctuations for problems of shock-particle interactions.

In pursuit of rigour and accountability in participatory design☆

PubMed Central

Frauenberger, Christopher; Good, Judith; Fitzpatrick, Geraldine; Iversen, Ole Sejer

2015-01-01

The field of Participatory Design (PD) has greatly diversified and we see a broad spectrum of approaches and methodologies emerging. However, to foster its role in designing future interactive technologies, a discussion about accountability and rigour across this spectrum is needed. Rejecting the traditional, positivistic framework, we take inspiration from related fields such as Design Research and Action Research to develop interpretations of these concepts that are rooted in PD׳s own belief system. We argue that unlike in other fields, accountability and rigour are nuanced concepts that are delivered through debate, critique and reflection. A key prerequisite for having such debates is the availability of a language that allows designers, researchers and practitioners to construct solid arguments about the appropriateness of their stances, choices and judgements. To this end, we propose a “tool-to-think-with” that provides such a language by guiding designers, researchers and practitioners through a process of systematic reflection and critical analysis. The tool proposes four lenses to critically reflect on the nature of a PD effort: epistemology, values, stakeholders and outcomes. In a subsequent step, the coherence between the revealed features is analysed and shows whether they pull the project in the same direction or work against each other. Regardless of the flavour of PD, we argue that this coherence of features indicates the level of internal rigour of PD work and that the process of reflection and analysis provides the language to argue for it. We envision our tool to be useful at all stages of PD work: in the planning phase, as part of a reflective practice during the work, and as a means to construct knowledge and advance the field after the fact. We ground our theoretical discussions in a specific PD experience, the ECHOES project, to motivate the tool and to illustrate its workings. PMID:26109833

[Primary healthcare and the construction of meanings of oral health: a social constructionist interpretation of discourses of the elderly].

PubMed

Bulgarelli, Alexandre Favero; Pinto, Ione Carvalho; Lorenzi, Carla Guanaes; Villa, Teresa Cristina Scatena; Mestriner, Soraya Fernandes; Silva, Rosalina Carvalho da

2012-05-01

Dentistry currently reveals itself to be open to new ideas about the construction of meanings for oral health. This openness leads to the social production of health revealing the contextualization of the social and historical aspects of the sundry knowledge in the development of oral health for different communities. With this research, we seek to build meanings for oral health with a group of elderly people. With this objective in mind, we propose an approximation between discourses on oral health mentioned by the elderly and the Social Constructionist discourse. We interviewed 14 elderly people enrolled in a Family Health Unit in Ribeirão Preto, State of São Paulo, in the first semester of 2010, and identified two interpretative repertoires through Discourse Analysis, which showed the relationship between 1 - Lack of information and dental assistance in childhood, and 2 - Primary Health Care building the meaning of oral health. We concluded that Social Constructionism works epistemologically for the construction of meanings for oral health and that primary health is essential for appreciation and health care that enables the construction of meanings in oral health by the elderly that create conditions for self-care and healthy attitudes.

Measurement of visibility from the pilot's cockpit on different airplane types

NASA Technical Reports Server (NTRS)

Kurz, Gerhard

1931-01-01

A process for the measurement of the visibility of airplanes from the pilot's cockpit is developed. The apparatus necessary for the measurements was suitably constructed and measurements of the fields of vision were made with it. The visibilities of six airplanes of different types of construction and use were measured, as well as the visibility of an automobile for comparison. An attempt was made to establish minimum visibility requirements and to express the excellence of visibility by means of a numerical coefficient.

Reflexive Clitics in the Slavic and Romance Languages. A Comparative View from an Antipassive Perspective

ERIC Educational Resources Information Center

Medova, Lucie

2009-01-01

In this work, I offer a unified analysis of all the constructions that involve a reflexive clitic SE in Slavic and Romance languages. Next to canonical constructions, in which the reflexive clitic semantically identifies the two arguments of a transitive verb, cf. "John" SE "wash" means "John washes himself," there are constructions in which it is…

The V-22 Osprey: A Case Analysis

DTIC Science & Technology

1992-06-01

Messerschmitt-Bolkow-Blohm Gmbh in West Germany, Westland Helicopters Ltd in England and Construcciones Aeronauticas SA in Spain, has organized to field a... construction of new runways and new airports - environmentally difficult in most urban areas - could be postponed or eliminated. D. TECHNOLOGY ISSUES...composite fiber construction in which the V-22 is a trailblazer. Bell-Boeing have found that composite construction provides strength, stiffness and

Molecular activity prediction by means of supervised subspace projection based ensembles of classifiers.

PubMed

Cerruela García, G; García-Pedrajas, N; Luque Ruiz, I; Gómez-Nieto, M Á

2018-03-01

This paper proposes a method for molecular activity prediction in QSAR studies using ensembles of classifiers constructed by means of two supervised subspace projection methods, namely nonparametric discriminant analysis (NDA) and hybrid discriminant analysis (HDA). We studied the performance of the proposed ensembles compared to classical ensemble methods using four molecular datasets and eight different models for the representation of the molecular structure. Using several measures and statistical tests for classifier comparison, we observe that our proposal improves the classification results with respect to classical ensemble methods. Therefore, we show that ensembles constructed using supervised subspace projections offer an effective way of creating classifiers in cheminformatics.

Constructing accountability in inter-organisational collaboration: the implications of a narrow performance-based focus.

PubMed

Andersson, Johanna; Wikström, Ewa

2014-01-01

The purpose of this paper is to analyse how accounts of collaboration practice were made and used to construct accountability in the empirical context of coordination associations, a Swedish form of collaboration between four authorities in health and social care. They feature pooled budgets, joint leadership and joint reporting systems, intended to facilitate both collaboration and (shared) accountability. Empirical data were collected in field observations in local, regional and national settings. In addition, the study is based on analysis of local association documents such as evaluations and annual reports, and analysis of national agency reports. Accountability is constructed hierarchically with a narrow focus on performance, and horizontal (shared) accountability as well as outcomes are de-emphasised. Through this narrow construction of accountability the coordination associations are re-created as hierarchical and accountability is delegated rather than shared. Features such as pooled budgets, joint leadership and joint reporting systems can support collaboration but do not necessarily translate into shared accountability if accountability is interpreted and constructed hierarchically. When practice conforms to what is counted and accounted for, using the hierarchical and narrow construction of accountability, the result may be that the associations become an additional authority. That would increase rather than decrease fragmentation in the field. This research derives from first-hand observations of actor-to-actor episodes complemented with the analysis of documents and reports. It provides critical analysis of the construction and evaluation of accounts and accountability related to practice and performance in collaboration. The main contribution is the finding that despite the conditions intended to facilitate inter-organisational collaboration and horizontal accountability, the hierarchical accountability persisted.

Distinguishing Grammatical Constructions with fMRI Pattern Analysis

ERIC Educational Resources Information Center

Allen, Kachina; Pereira, Francisco; Botvinick, Matthew; Goldberg, Adele E.

2012-01-01

All linguistic and psycholinguistic theories aim to provide psychologically valid analyses of particular grammatical patterns and the relationships that hold among them. Until recently, no tools were available to distinguish neural correlates of particular grammatical constructions that shared the same content words, propositional meaning, and…

ROOTing Out Meaning: More Morphemic Analysis for Primary Pupils

ERIC Educational Resources Information Center

Mountain, Lee

2005-01-01

In an elementary-school professional development program, a group of primary teachers and a university consultant reviewed the research on morphemic analysis and then explored ways to give pupils in grades 1, 2, and 3 an early start on using prefixes, suffixes, and roots to construct word meaning. The teachers examined some middle-grade strategies…

A stochastic model for optimizing composite predictors based on gene expression profiles.

PubMed

Ramanathan, Murali

2003-07-01

This project was done to develop a mathematical model for optimizing composite predictors based on gene expression profiles from DNA arrays and proteomics. The problem was amenable to a formulation and solution analogous to the portfolio optimization problem in mathematical finance: it requires the optimization of a quadratic function subject to linear constraints. The performance of the approach was compared to that of neighborhood analysis using a data set containing cDNA array-derived gene expression profiles from 14 multiple sclerosis patients receiving intramuscular inteferon-beta1a. The Markowitz portfolio model predicts that the covariance between genes can be exploited to construct an efficient composite. The model predicts that a composite is not needed for maximizing the mean value of a treatment effect: only a single gene is needed, but the usefulness of the effect measure may be compromised by high variability. The model optimized the composite to yield the highest mean for a given level of variability or the least variability for a given mean level. The choices that meet this optimization criteria lie on a curve of composite mean vs. composite variability plot referred to as the "efficient frontier." When a composite is constructed using the model, it outperforms the composite constructed using the neighborhood analysis method. The Markowitz portfolio model may find potential applications in constructing composite biomarkers and in the pharmacogenomic modeling of treatment effects derived from gene expression endpoints.

Two Populations Mean-Field Monomer-Dimer Model

NASA Astrophysics Data System (ADS)

Alberici, Diego; Mingione, Emanuele

2018-04-01

A two populations mean-field monomer-dimer model including both hard-core and attractive interactions between dimers is considered. The pressure density in the thermodynamic limit is proved to satisfy a variational principle. A detailed analysis is made in the limit of one population is much smaller than the other and a ferromagnetic mean-field phase transition is found.

Weighting and Aggregation in Composite Indicator Construction: A Multiplicative Optimization Approach

ERIC Educational Resources Information Center

Zhou, P.; Ang, B. W.; Zhou, D. Q.

2010-01-01

Composite indicators (CIs) have increasingly been accepted as a useful tool for benchmarking, performance comparisons, policy analysis and public communication in many different fields. Several recent studies show that as a data aggregation technique in CI construction the weighted product (WP) method has some desirable properties. However, a…

A four-dimensional motion field atlas of the tongue from tagged and cine magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Xing, Fangxu; Prince, Jerry L.; Stone, Maureen; Wedeen, Van J.; El Fakhri, Georges; Woo, Jonghye

2017-02-01

Representation of human tongue motion using three-dimensional vector fields over time can be used to better understand tongue function during speech, swallowing, and other lingual behaviors. To characterize the inter-subject variability of the tongue's shape and motion of a population carrying out one of these functions it is desirable to build a statistical model of the four-dimensional (4D) tongue. In this paper, we propose a method to construct a spatio-temporal atlas of tongue motion using magnetic resonance (MR) images acquired from fourteen healthy human subjects. First, cine MR images revealing the anatomical features of the tongue are used to construct a 4D intensity image atlas. Second, tagged MR images acquired to capture internal motion are used to compute a dense motion field at each time frame using a phase-based motion tracking method. Third, motion fields from each subject are pulled back to the cine atlas space using the deformation fields computed during the cine atlas construction. Finally, a spatio-temporal motion field atlas is created to show a sequence of mean motion fields and their inter-subject variation. The quality of the atlas was evaluated by deforming cine images in the atlas space. Comparison between deformed and original cine images showed high correspondence. The proposed method provides a quantitative representation to observe the commonality and variability of the tongue motion field for the first time, and shows potential in evaluation of common properties such as strains and other tensors based on motion fields.

A Four-dimensional Motion Field Atlas of the Tongue from Tagged and Cine Magnetic Resonance Imaging.

PubMed

Xing, Fangxu; Prince, Jerry L; Stone, Maureen; Wedeen, Van J; Fakhri, Georges El; Woo, Jonghye

2017-01-01

Representation of human tongue motion using three-dimensional vector fields over time can be used to better understand tongue function during speech, swallowing, and other lingual behaviors. To characterize the inter-subject variability of the tongue's shape and motion of a population carrying out one of these functions it is desirable to build a statistical model of the four-dimensional (4D) tongue. In this paper, we propose a method to construct a spatio-temporal atlas of tongue motion using magnetic resonance (MR) images acquired from fourteen healthy human subjects. First, cine MR images revealing the anatomical features of the tongue are used to construct a 4D intensity image atlas. Second, tagged MR images acquired to capture internal motion are used to compute a dense motion field at each time frame using a phase-based motion tracking method. Third, motion fields from each subject are pulled back to the cine atlas space using the deformation fields computed during the cine atlas construction. Finally, a spatio-temporal motion field atlas is created to show a sequence of mean motion fields and their inter-subject variation. The quality of the atlas was evaluated by deforming cine images in the atlas space. Comparison between deformed and original cine images showed high correspondence. The proposed method provides a quantitative representation to observe the commonality and variability of the tongue motion field for the first time, and shows potential in evaluation of common properties such as strains and other tensors based on motion fields.

Constructing, Consuming, and Complicating the Human-Nature Binary: Communication Practices in Forest Environmental Education

ERIC Educational Resources Information Center

Dickinson, Elizabeth A.

2010-01-01

This project combines interdisciplinary conversations within the field of communication to examine environmental meaning systems and communication practices in the context of forest environmental education. Due to concerns over children's environmental alienation, there has been a continued push toward place-based environmental education. One such…

Affordances: Ten Years On

ERIC Educational Resources Information Center

Brown, Jill P.; Stillman, Gloria

2014-01-01

Ten years ago the construct, affordance, was rising in prominence in scholarly literature. A proliferation of different uses and meanings was evident. Beginning with its origin in the work of Gibson, we traced its development and use in various scholarly fields. This paper revisits our original question with respect to its utility in mathematics…

Global maps of the magnetic thickness and magnetization of the Earth's lithosphere

NASA Astrophysics Data System (ADS)

Vervelidou, Foteini; Thébault, Erwan

2015-10-01

We have constructed global maps of the large-scale magnetic thickness and magnetization of Earth's lithosphere. Deriving such large-scale maps based on lithospheric magnetic field measurements faces the challenge of the masking effect of the core field. In this study, the maps were obtained through analyses in the spectral domain by means of a new regional spatial power spectrum based on the Revised Spherical Cap Harmonic Analysis (R-SCHA) formalism. A series of regional spectral analyses were conducted covering the entire Earth. The R-SCHA surface power spectrum for each region was estimated using the NGDC-720 spherical harmonic (SH) model of the lithospheric magnetic field, which is based on satellite, aeromagnetic, and marine measurements. These observational regional spectra were fitted to a recently proposed statistical expression of the power spectrum of Earth's lithospheric magnetic field, whose free parameters include the thickness and magnetization of the magnetic sources. The resulting global magnetic thickness map is compared to other crustal and magnetic thickness maps based upon different geophysical data. We conclude that the large-scale magnetic thickness of the lithosphere is on average confined to a layer that does not exceed the Moho.

The construction of meaning.

PubMed

Kintsch, Walter; Mangalath, Praful

2011-04-01

We argue that word meanings are not stored in a mental lexicon but are generated in the context of working memory from long-term memory traces that record our experience with words. Current statistical models of semantics, such as latent semantic analysis and the Topic model, describe what is stored in long-term memory. The CI-2 model describes how this information is used to construct sentence meanings. This model is a dual-memory model, in that it distinguishes between a gist level and an explicit level. It also incorporates syntactic information about how words are used, derived from dependency grammar. The construction of meaning is conceptualized as feature sampling from the explicit memory traces, with the constraint that the sampling must be contextually relevant both semantically and syntactically. Semantic relevance is achieved by sampling topically relevant features; local syntactic constraints as expressed by dependency relations ensure syntactic relevance. Copyright © 2010 Cognitive Science Society, Inc.

Loop expansion around the Bethe approximation through the M-layer construction

NASA Astrophysics Data System (ADS)

Altieri, Ada; Chiara Angelini, Maria; Lucibello, Carlo; Parisi, Giorgio; Ricci-Tersenghi, Federico; Rizzo, Tommaso

2017-11-01

For every physical model defined on a generic graph or factor graph, the Bethe M-layer construction allows building a different model for which the Bethe approximation is exact in the large M limit, and coincides with the original model for M=1 . The 1/M perturbative series is then expressed by a diagrammatic loop expansion in terms of so-called fat diagrams. Our motivation is to study some important second-order phase transitions that do exist on the Bethe lattice, but are either qualitatively different or absent in the corresponding fully connected case. In this case, the standard approach based on a perturbative expansion around the naive mean field theory (essentially a fully connected model) fails. On physical grounds, we expect that when the construction is applied to a lattice in finite dimension there is a small region of the external parameters, close to the Bethe critical point, where strong deviations from mean-field behavior will be observed. In this region, the 1/M expansion for the corrections diverges, and can be the starting point for determining the correct non-mean-field critical exponents using renormalization group arguments. In the end, we will show that the critical series for the generic observable can be expressed as a sum of Feynman diagrams with the same numerical prefactors of field theories. However, the contribution of a given diagram is not evaluated by associating Gaussian propagators to its lines, as in field theories: one has to consider the graph as a portion of the original lattice, replacing the internal lines with appropriate one-dimensional chains, and attaching to the internal points the appropriate number of infinite-size Bethe trees to restore the correct local connectivity of the original model. The actual contribution of each (fat) diagram is the so-called line-connected observable, which also includes contributions from sub-diagrams with appropriate prefactors. In order to compute the corrections near to the critical point, Feynman diagrams (with their symmetry factors) can be read directly from the appropriate field-theoretical literature; the computation of momentum integrals is also quite similar; the extra work consists of computing the line-connected observable of the associated fat diagram in the limit of all lines becoming infinitely long.

Harmonic Analysis and Free Field Realization of the Takiff Supergroup of GL(1|1)

NASA Astrophysics Data System (ADS)

Babichenko, Andrei; Creutzig, Thomas

2015-08-01

Takiff superalgebras are a family of non semi-simple Lie superalgebras that are believed to give rise to a rich structure of indecomposable representations of associated conformal field theories. We consider the Takiff superalgebra of gl(1\\vert 1), especially we perform harmonic analysis for the corresponding supergroup. We find that every simple module appears as submodule of an infinite-dimensional indecomposable but reducible module. We lift our results to two free field realizations for the corresponding conformal field theory and construct some modules.

Multivariate Markov chain modeling for stock markets

NASA Astrophysics Data System (ADS)

Maskawa, Jun-ichi

2003-06-01

We study a multivariate Markov chain model as a stochastic model of the price changes of portfolios in the framework of the mean field approximation. The time series of price changes are coded into the sequences of up and down spins according to their signs. We start with the discussion for small portfolios consisting of two stock issues. The generalization of our model to arbitrary size of portfolio is constructed by a recurrence relation. The resultant form of the joint probability of the stationary state coincides with Gibbs measure assigned to each configuration of spin glass model. Through the analysis of actual portfolios, it has been shown that the synchronization of the direction of the price changes is well described by the model.

Visual analysis of online social media to open up the investigation of stance phenomena

PubMed Central

Kucher, Kostiantyn; Schamp-Bjerede, Teri; Kerren, Andreas; Paradis, Carita; Sahlgren, Magnus

2015-01-01

Online social media are a perfect text source for stance analysis. Stance in human communication is concerned with speaker attitudes, beliefs, feelings and opinions. Expressions of stance are associated with the speakers' view of what they are talking about and what is up for discussion and negotiation in the intersubjective exchange. Taking stance is thus crucial for the social construction of meaning. Increased knowledge of stance can be useful for many application fields such as business intelligence, security analytics, or social media monitoring. In order to process large amounts of text data for stance analyses, linguists need interactive tools to explore the textual sources as well as the processed data based on computational linguistics techniques. Both original texts and derived data are important for refining the analyses iteratively. In this work, we present a visual analytics tool for online social media text data that can be used to open up the investigation of stance phenomena. Our approach complements traditional linguistic analysis techniques and is based on the analysis of utterances associated with two stance categories: sentiment and certainty. Our contributions include (1) the description of a novel web-based solution for analyzing the use and patterns of stance meanings and expressions in human communication over time; and (2) specialized techniques used for visualizing analysis provenance and corpus overview/navigation. We demonstrate our approach by means of text media on a highly controversial scandal with regard to expressions of anger and provide an expert review from linguists who have been using our tool. PMID:29249903

Visual analysis of online social media to open up the investigation of stance phenomena.

PubMed

Kucher, Kostiantyn; Schamp-Bjerede, Teri; Kerren, Andreas; Paradis, Carita; Sahlgren, Magnus

2016-04-01

Online social media are a perfect text source for stance analysis. Stance in human communication is concerned with speaker attitudes, beliefs, feelings and opinions. Expressions of stance are associated with the speakers' view of what they are talking about and what is up for discussion and negotiation in the intersubjective exchange. Taking stance is thus crucial for the social construction of meaning. Increased knowledge of stance can be useful for many application fields such as business intelligence, security analytics, or social media monitoring. In order to process large amounts of text data for stance analyses, linguists need interactive tools to explore the textual sources as well as the processed data based on computational linguistics techniques. Both original texts and derived data are important for refining the analyses iteratively. In this work, we present a visual analytics tool for online social media text data that can be used to open up the investigation of stance phenomena. Our approach complements traditional linguistic analysis techniques and is based on the analysis of utterances associated with two stance categories: sentiment and certainty. Our contributions include (1) the description of a novel web-based solution for analyzing the use and patterns of stance meanings and expressions in human communication over time; and (2) specialized techniques used for visualizing analysis provenance and corpus overview/navigation. We demonstrate our approach by means of text media on a highly controversial scandal with regard to expressions of anger and provide an expert review from linguists who have been using our tool.

Evidence of validity of the Stress-Producing Life Events (SPLE) instrument.

PubMed

Rizzini, Marta; Santos, Alcione Miranda Dos; Silva, Antônio Augusto Moura da

2018-01-01

OBJECTIVE Evaluate the construct validity of a list of eight Stressful Life Events in pregnant women. METHODS A cross-sectional study was conducted with 1,446 pregnant women in São Luís, MA, and 1,364 pregnant women in Ribeirão Preto, SP (BRISA cohort), from February 2010 to June 2011. In the exploratory factorial analysis, the promax oblique rotation was used and for the calculation of the internal consistency, we used the compound reliability. The construct validity was determined by means of the confirmatory factorial analysis with the method of estimation of weighted least squares adjusted by the mean and variance. RESULTS The model with the best fit in the exploratory analysis was the one that retained three factors with a cumulative variance of 61.1%. The one-factor model did not obtain a good fit in both samples in the confirmatory analysis. The three-factor model called Stress-Producing Life Events presented a good fit (RMSEA < 0.05; CFI/TLI > 0.90) for both samples. CONCLUSIONS The Stress-Producing Life Events constitute a second order construct with three dimensions related to health, personal and financial aspects and violence. This study found evidence that confirms the construct validity of a list of stressor events, entitled Stress-Producing Life Events Inventory.

Unification Principle and a Geometric Field Theory

NASA Astrophysics Data System (ADS)

Wanas, Mamdouh I.; Osman, Samah N.; El-Kholy, Reham I.

2015-08-01

In the context of the geometrization philosophy, a covariant field theory is constructed. The theory satisfies the unification principle. The field equations of the theory are constructed depending on a general differential identity in the geometry used. The Lagrangian scalar used in the formalism is neither curvature scalar nor torsion scalar, but an alloy made of both, the W-scalar. The physical contents of the theory are explored depending on different methods. The analysis shows that the theory is capable of dealing with gravity, electromagnetism and material distribution with possible mutual interactions. The theory is shown to cover the domain of general relativity under certain conditions.

Comment on ``Steady-state properties of a totally asymmetric exclusion process with periodic structure''

NASA Astrophysics Data System (ADS)

Jiang, Rui; Hu, Mao-Bin; Wu, Qing-Song

2008-07-01

Lakatos [Phys. Rev. E 71, 011103 (2005)] have studied a totally asymmetric exclusion process that contains periodically varying movement rates. They have presented a cluster mean-field theory for the problem. We show that their cluster mean-field theory leads to redundant equations. We present a mean-field analysis in which there is no redundant equation.

Event Structure and Grammatical Patterns: Resultative Constructions

ERIC Educational Resources Information Center

Lee, Leslie

2013-01-01

This thesis investigates the nature of grammatical patterns through an in-depth study of resultative constructions in Mandarin and Thai. At the heart of the thesis lies the proposal that event structure templates--complex, meaning-based grammatical patterns--must be recognised as primary objects of linguistic analysis. As content-theoretic objects…

Critical study of the dispersive n- 90Zr mean field by means of a new variational method

NASA Astrophysics Data System (ADS)

Mahaux, C.; Sartor, R.

1994-02-01

A new variational method is developed for the construction of the dispersive nucleon-nucleus mean field at negative and positive energies. Like the variational moment approach that we had previously proposed, the new method only uses phenomenological optical-model potentials as input. It is simpler and more flexible than the previous approach. It is applied to a critical investigation of the n- 90Zr mean field between -25 and +25 MeV. This system is of particular interest because conflicting results had recently been obtained by two different groups. While the imaginary parts of the phenomenological optical-model potentials provided by these two groups are similar, their real parts are quite different. Nevertheless, we demonstrate that these two sets of phenomenological optical-model potentials are both compatible with the dispersion relation which connects the real and imaginary parts of the mean field. Previous hints to the contrary, by one of the two other groups, are shown to be due to unjustified approximations. A striking outcome of the present study is that it is important to explicitly introduce volume absorption in the dispersion relation, although volume absorption is negligible in the energy domain investigated here. Because of the existence of two sets of phenomenological optical-model potentials, our variational method yields two dispersive mean fields whose real parts are quite different at small or negative energies. No preference for one of the two dispersive mean fields can be expressed on purely empirical grounds since they both yield fair agreement with the experimental cross sections as well as with the observed energies of the bound single-particle states. However, we argue that one of these two mean fields is physically more meaningful, because the radial shape of its Hartree-Fock type component is independent of energy, as expected on theoretical grounds. This preferred mean field is very close to the one which had been obtained by the Ohio University group by means of fits to experimental cross sections. It is also in good agreement with a recent determination of the p- 90Zr average potential.

A Methodology for Developing Evidence about Meaning in Occupation: Exploring the Meaning of Working.

ERIC Educational Resources Information Center

Baker, Nancy A.; Jacobs, Karen; Tickle-Degnen, Linda

2003-01-01

The Meaning of Working Survey, with the constructs of work centrality, societal work norms, and valued work outcomes, was completed by 170 workers. They did not view work as central, but as a constraint or reciprocal arrangement. They valued benefits and wages over intrinsic outcomes. Cluster analysis revealed that work meanings were related to…

Impacts of cooling intervention on the heat strain attenuation of construction workers

NASA Astrophysics Data System (ADS)

Zhao, Yijie; Yi, Wen; Chan, Albert P. C.; Wong, Del P.

2018-05-01

This study aimed to evaluate the effectiveness and practicality of a cooling intervention with a newly designed cooling vest on heat strain attenuation in the construction industry. Fourteen construction workers volunteered to participate in the field study. Each participant took part in two trials, i.e., cooling and control. Construction work included morning and afternoon sessions. Cooling intervention was implemented for 15 and 30 min during the morning and afternoon rest periods, respectively, between repeated bouts of work. Micrometeorological (wet-bulb globe temperature [WBGT]), physiological (tympanic temperature and heart rate), and perceptual (ratings of perceived exertion [RPE] and thermal sensation) measurements were taken during the test. Heat strain indices, including physiological strain index (PSIHR) and perceptual strain index (PeSI), were estimated accordingly. During the study, construction workers were exposed to a hot environment with a mean WBGT of 31.56 ± 1.87 °C. Compared with the control, physiological and perceptual strain were significantly reduced in the cooling condition during rest and subsequent work periods (p < 0.05; d = 0.24-1.07, small to large cooling effect). Cooling intervention significantly alleviates heat strain in the construction industry. The effectiveness and practicality of a proposed cooling intervention were tested in a field study. Results provide a reference for setting guidelines and promoting application on a range of construction sites.

Impacts of cooling intervention on the heat strain attenuation of construction workers.

PubMed

Zhao, Yijie; Yi, Wen; Chan, Albert P C; Wong, Del P

2018-05-25

This study aimed to evaluate the effectiveness and practicality of a cooling intervention with a newly designed cooling vest on heat strain attenuation in the construction industry. Fourteen construction workers volunteered to participate in the field study. Each participant took part in two trials, i.e., cooling and control. Construction work included morning and afternoon sessions. Cooling intervention was implemented for 15 and 30 min during the morning and afternoon rest periods, respectively, between repeated bouts of work. Micrometeorological (wet-bulb globe temperature [WBGT]), physiological (tympanic temperature and heart rate), and perceptual (ratings of perceived exertion [RPE] and thermal sensation) measurements were taken during the test. Heat strain indices, including physiological strain index (PSI HR ) and perceptual strain index (PeSI), were estimated accordingly. During the study, construction workers were exposed to a hot environment with a mean WBGT of 31.56 ± 1.87 °C. Compared with the control, physiological and perceptual strain were significantly reduced in the cooling condition during rest and subsequent work periods (p < 0.05; d = 0.24-1.07, small to large cooling effect). Cooling intervention significantly alleviates heat strain in the construction industry. The effectiveness and practicality of a proposed cooling intervention were tested in a field study. Results provide a reference for setting guidelines and promoting application on a range of construction sites.

Discourse analysis and social constructionism.

PubMed

White, Robert

2004-10-01

Discourse analysis (DA) is underpinned by a social constructionist orientation to knowledge. Social constructionism rests on the philosophical assumptions that multiple versions of the world are legitimate; that texts are open to multiple readings; and that language is non-representational. As social constructionism is relativistic, the status of 'evidence' generated by DA is questionable from more traditional research perspectives. On a common-sense level, people obviously construct meaning in relation to their lives. Thus, DA can help us to examine constructions of meaning in relation to nursing care. Equally, the discourse analyst constructs one possible meaning in relation to a phenomenon that may compete with other versions. Multiplicity does not necessarily entail anarchy, and competing versions prevent authoritarianism and loss of freedom. However, judgements have to be made about competing versions, for example, by assessing the level of 'facticity', or referring to the ethics embedded in the cultural context. In this paper, Bob White discusses DA as a form of qualitative research that offers promise for nursing research. Subsequent papers will examine the methodology and methods of DA and its application to nursing research.

Discourse analysis and social constructionism.

PubMed

White, Robert

2004-01-01

Discourse analysis (DA) is underpinned by a social constructionist orientation to knowledge. Social constructionism rests on the philosophical assumptions that multiple versions of the world are legitimate; that texts are open to multiple readings; and that language is non-representational. As social constructionism is relativistic, the status of 'evidence' generated by DA is questionable from more traditional research perspectives. On a common-sense level, people obviously construct meaning in relation to their lives. Thus, DA can help us to examine constructions of meaning in relation to nursing care. Equally the discourse analyst constructs one possible meaning in relation to a phenomenon that may compete with other versions. Multiplicity does not necessarily entail anarchy and competing versions prevent authoritarianism and loss of freedom. However, judgements have to be made about competing versions, for example, by assessing the level of 'facticity', or referring to the ethics embedded in the cultural context. In this paper, Bob White discusses DA as a form of qualitative research that offers promise for nursing research. Subsequent papers will examine the methodology and methods of DA and its application to nursing research.

How to Define the Mean Square Amplitude of Solar Wind Fluctuations With Respect to the Local Mean Magnetic Field

NASA Astrophysics Data System (ADS)

Podesta, John J.

2017-12-01

Over the last decade it has become popular to analyze turbulent solar wind fluctuations with respect to a coordinate system aligned with the local mean magnetic field. This useful analysis technique has provided new information and new insights about the nature of solar wind fluctuations and provided some support for phenomenological theories of MHD turbulence based on the ideas of Goldreich and Sridhar. At the same time it has drawn criticism suggesting that the use of a scale-dependent local mean field is somehow inconsistent or irreconcilable with traditional analysis techniques based on second-order structure functions and power spectra that, for stationary time series, are defined with respect to the constant (scale-independent) ensemble average magnetic field. Here it is shown that for fluctuations with power law spectra, such as those observed in solar wind turbulence, it is possible to define the local mean magnetic field in a special way such that the total mean square amplitude (trace amplitude) of turbulent fluctuations is approximately the same, scale by scale, as that obtained using traditional second-order structure functions or power spectra. This fact should dispel criticism concerning the physical validity or practical usefulness of the local mean magnetic field in these applications.

Exploring Ghanaian adolescents’ meaning of health and wellbeing: A psychosocial perspective

PubMed Central

Glozah, Franklin N.

2015-01-01

There is presently no internationally agreed upon set of indicators for assessing adolescent health and what “health and wellbeing” means to adolescents. The psychosocial context of family, friends, and school plays a crucial role in the construction of health and wellbeing by adolescents. In spite of this, not much is known about the meaning Ghanaian adolescents attach to their health and wellbeing and the role of stress and social support in the construction of this meaning. This study explores how perceived social support and stress influence the construction of the meaning of health and wellbeing to Ghanaian adolescents. Eleven respondents purposively selected from 770 males and females participated in semi-structured interviews, which were transcribed verbatim and analysed with thematic analysis. Findings pointed to the fact that health and wellbeing was largely construed as “ability to perform daily functions,” such as ability to take critical decisions and a general sense of vitality and mental strength. These were influenced by perceived social support (“encouragement and advice” and “religiosity or spirituality”) and stress (“teasing, strictness, quarrels, and arguments”). These findings suggest that effective communication, mutual respect, and support from significant others, in the midst of stressful life events, contribute substantially to a holistic construction and meaning of health and wellbeing by Ghanaian adolescents. PMID:25855158

Exploring Ghanaian adolescents' meaning of health and wellbeing: a psychosocial perspective.

PubMed

Glozah, Franklin N

2015-01-01

There is presently no internationally agreed upon set of indicators for assessing adolescent health and what "health and wellbeing" means to adolescents. The psychosocial context of family, friends, and school plays a crucial role in the construction of health and wellbeing by adolescents. In spite of this, not much is known about the meaning Ghanaian adolescents attach to their health and wellbeing and the role of stress and social support in the construction of this meaning. This study explores how perceived social support and stress influence the construction of the meaning of health and wellbeing to Ghanaian adolescents. Eleven respondents purposively selected from 770 males and females participated in semi-structured interviews, which were transcribed verbatim and analysed with thematic analysis. Findings pointed to the fact that health and wellbeing was largely construed as "ability to perform daily functions," such as ability to take critical decisions and a general sense of vitality and mental strength. These were influenced by perceived social support ("encouragement and advice" and "religiosity or spirituality") and stress ("teasing, strictness, quarrels, and arguments"). These findings suggest that effective communication, mutual respect, and support from significant others, in the midst of stressful life events, contribute substantially to a holistic construction and meaning of health and wellbeing by Ghanaian adolescents.

An Analysis of Constructivism and the Ancient Art of Origami

ERIC Educational Resources Information Center

Sze, Susan

2005-01-01

This paper provides a framework for thinking about origami construction and constructivism. In an attempt to understand the conceptual and theoretical framework supporting the field of inclusive teaching strategies in relationship to origami, I have prepared a model for origami which represents six types of constructive learning: (1) Hands-on…

Using reclaimed lumber and wood flooring in construction : measuring environmental impact using life-cycle inventory analysis

Treesearch

Richard D. Bergman; Hongmei Gu; Robert H. Falk; Thomas R. Napier

2010-01-01

With green building concepts becoming widespread in the construction field, building practices and materials are being examined for their environmental impact. Reusing building materials has a distinct advantage over using newly manufactured materials because these reclaimed materials avoid greenhouse gas emissions associated with new (virgin) material manufacturing....

An Interpretation of Juvenile Parolees' Gender Constructions at School

ERIC Educational Resources Information Center

Smith, Brain J.

2002-01-01

This paper focuses on inner-city juvenile parolees' gendered interactions at a community school in a large southwestern city. The analysis seeks to interpret the students' gender constructions within the contexts of cultural ideologies and social-structural locations. Drawing from a year of field research at the school and interviews with youths…

The “shape” and “meaning” of the roof arts in Chinese classical architecture

NASA Astrophysics Data System (ADS)

Li, Xianda; liu, Yu

2017-04-01

This paper takes the “roof” in Chinese classical architecture as the research object. The breakthrough point of this paper would be the perspective of design aesthetics. Through the rational and perceptual analysis of the roof art, this paper would reveal that the roof shape has the double artistic features: “beauty of shape” and “beauty of idea”. This paper would have a comprehensive analysis for the following aspects: the rational method of roof construction, the emotional feeling of the roof construction and the implied meaning of beauty in the roof construction.

Metastates in Mean-Field Models with Random External Fields Generated by Markov Chains

NASA Astrophysics Data System (ADS)

Formentin, M.; Külske, C.; Reichenbachs, A.

2012-01-01

We extend the construction by Külske and Iacobelli of metastates in finite-state mean-field models in independent disorder to situations where the local disorder terms are a sample of an external ergodic Markov chain in equilibrium. We show that for non-degenerate Markov chains, the structure of the theorems is analogous to the case of i.i.d. variables when the limiting weights in the metastate are expressed with the aid of a CLT for the occupation time measure of the chain. As a new phenomenon we also show in a Potts example that for a degenerate non-reversible chain this CLT approximation is not enough, and that the metastate can have less symmetry than the symmetry of the interaction and a Gaussian approximation of disorder fluctuations would suggest.

Employability, Managerialism, and Performativity in Higher Education: A Relational Perspective

ERIC Educational Resources Information Center

Kalfa, Senia; Taksa, Lucy

2017-01-01

This article combines Bourdieu's concepts of field, habitus and cultural capital with Lyotard's account of performativity to construct a three-tiered framework in order to explore how managerialism has affected the academic habitus. Specifically, this article examines the adoption of group assignments as a means of developing teamwork skills in…

Reflecting on a Difficult Life: Narrative Construction in Vulnerable Adolescents

ERIC Educational Resources Information Center

McLean, Kate C.; Wood, Becky; Breen, Andrea V.

2013-01-01

We examined narrative processes of identity development as they related to desistance from delinquent behavior in a sample of vulnerable adolescents. Building on a robust theoretical and empirical foundation in the field of narrative identity, we examined processes of meaning-making and agency in relation to desistance. Thirty-one adolescents were…

Assessing the Field Course Experiential Learning Model: Transforming Collegiate Short-Term Study Abroad Experiences into Rich Learning Environments

ERIC Educational Resources Information Center

McLaughlin, Jacqueline S.; Johnson, D. Kent

2006-01-01

Constructivist learning theory holds that "learning consists less in recording information than in interpreting it. To interpret what is received and is attended to, the learner must personally construct meaning for it." Unfortunately, opportunities for interpreting conceptual information are often lacking in classroom…

Generative Phonology in the Clinic. CLCS Occasional Paper No. 10.

ERIC Educational Resources Information Center

Kallen, Jeffrey L.

A discussion of the use of generative phonology in the speech clinic, especially with children, begins with an outline of some constructs of generative phonology. First, some notes on phonetic notation and definitions of terms used in nongenerative phonology that have special meanings in this field are presented. Then a discussion of distinctive…

Beauty, Brains, and Brawn: The Construction of Gender in Children's Literature.

ERIC Educational Resources Information Center

Lehr, Susan, Ed.

This collection of essays offers diverse perspectives on what it means to be a male or female child in children's literature, presenting stimulating views from the field's best-known authors, illustrators, and educators. Among the authors and illustrators in the collection who talk about the creative process are: Jerry Pinckney, Katherine…

A Knowledge Engineering Approach to Develop Domain Ontology

ERIC Educational Resources Information Center

Yun, Hongyan; Xu, Jianliang; Xiong, Jing; Wei, Moji

2011-01-01

Ontologies are one of the most popular and widespread means of knowledge representation and reuse. A few research groups have proposed a series of methodologies for developing their own standard ontologies. However, because this ontological construction concerns special fields, there is no standard method to build domain ontology. In this paper,…

Statistical, Practical, Clinical, and Personal Significance: Definitions and Applications in Speech-Language Pathology

ERIC Educational Resources Information Center

Bothe, Anne K.; Richardson, Jessica D.

2011-01-01

Purpose: To discuss constructs and methods related to assessing the magnitude and the meaning of clinical outcomes, with a focus on applications in speech-language pathology. Method: Professionals in medicine, allied health, psychology, education, and many other fields have long been concerned with issues referred to variously as practical…

Changing over a Project Changing over: A Project-Research Supervision as a Conversation

ERIC Educational Resources Information Center

Clarke, Helen; Ryan, Charly

2006-01-01

Extracts from the written conversation between research student and supervisor show the nature of educative research supervision. The authors argue that researcher-supervisor relationships are methodological in nature as they shape and influence the people, the project and the field. Such relationships, which construct meanings, are complex. A…

14 CFR 152.605 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) Consideration of using alternative, renewable energy sources. Major building modification means modification of... AIRPORT AID PROGRAM Energy Conservation in Airport Aid Program § 152.605 Definitions. As used in this... the program, which will exceed $200,000 in construction cost. Energy assessment means an analysis of...

[Social representation of AIDS among students of Mexico City].

PubMed

Flores-Palacios, Fátima; Leyva-Flores, René

2003-01-01

To analyze the social representation of AIDS in a group of high school students aged 16 to 23 years in Mexico City. A non-probabilistic, cross-sectional research was carried out in a public high school in Mexico City. Students of all grades were invited to participate in the study, which took place between 1999 and 2000. Forty-six students participated; 28% male and 72% female. This exploratory field study consisted of three phases, each to address one of three dimensions: cognitive using free association techniques, representational field using semi-structured interviews; and context attitude by means of two discussion groups. In the latter, the information was previously collected for discussion. The cognitive nucleus on AIDS included the association between sex, disease, and death. The representational field of AIDS is constructed around the transmission-prevention unit. Construct elements are virus, contagion, sex, protection, and condom. An ambivalent attitude was identified towards HIV prevention and transmission: "We are only half responsible". Situations such as "rape, blood transfusions, infected syringes" were prominent in the discussion group, deemed beyond their control to prevent transmission, thus explaining the group's ambivalent attitude towards prevention. The usefulness of condoms was associated with prevention of pregnancy rather than with prevention of sexually transmitted infections. The social representation of HIV/AIDS in young students conforms a multidimensional corpus where different elements of scientific order and common sense converge and interact, such as beliefs, myths, taboos, and fears. All of these contribute to construct the meaning of AIDS. The English version of this paper is available at:http://www.insp.mx/salud/index.html.

[Resources and their meaning for caregivers--a gap in research? Health sociological and empirical approach to a hitherto neglected field of research].

PubMed

Mischke, Claudia

2012-06-01

Family caregiving changes everyday life. Caregivers deal with the new situation in different ways and they feel more or less stressful. Actually there is little knowledge about possible causes of this situation. But there is an assumption that using varied resources and coping strategies lead to differences in health outcomes and well-being. As caregiving is a phase of life with special stressors, the caregiver needs specific resources to cope with these requirements. According to Antonovsky (1997) and Hobfoll (1989), this research asks which resources caregivers poses and use to deal with the unusual situation. On the basis of a salutogenetic and resource-orientated theoretical approach and additional qualitative analysis of interviews important resources for caregivers will be identified. The results lead on the one hand to the construction of an assessment instrument and on the other hand facilitate nurses to get to know more about the individual approach of resources and their specific meaning for caregivers.

Assessing and grouping chemicals applying partial ordering Alkyl anilines as an illustrative example.

PubMed

Carlsen, Lars; Bruggemann, Rainer

2018-06-03

In chemistry there is a long tradition in classification. Usually methods are adopted from the wide field of cluster analysis. Here, based on the example of 21 alkyl anilines we show that also concepts taken out from the mathematical discipline of partially ordered sets may also be applied. The chemical compounds are described by a multi-indicator system. For the present study four indicators, mainly taken from the field of environmental chemistry were applied and a Hasse diagram was constructed. A Hasse diagram is an acyclic, transitively reduced, triangle free graph that may have several components. The crucial question is, whether or not the Hasse diagram can be interpreted from a structural chemical point of view. This is indeed the case, but it must be clearly stated that a guarantee for meaningful results in general cannot be given. For that further theoretical work is needed. Two cluster analysis methods are applied (K-means and a hierarchical cluster method). In both cases the partitioning of the set of 21 compounds by the component structure of the Hasse diagram appears to be better interpretable. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

On-farm irrigation reservoirs for surface water storage in eastern Arkansas: Trends in construction in response to aquifer depletion

NASA Astrophysics Data System (ADS)

Yaeger, M. A.; Reba, M. L.; Massey, J. H.; Adviento-Borbe, A.

2017-12-01

On-farm surface water storage reservoirs have been constructed to address declines in the Mississippi River Valley Alluvial aquifer, the primary source of irrigation for most of the row crops grown in eastern Arkansas. These reservoirs and their associated infrastructure represent significant investments in financial and natural resources, and may cause producers to incur costs associated with foregone crop production and long-term maintenance. Thus, an analysis of reservoir construction trends in the Grand Prairie Critical Groundwater Area (GPCGA) and Cache River Critical Groundwater Area (CRCGA) was conducted to assist future water management decisions. Between 1996 and 2015, on average, 16 and 4 reservoirs were constructed per year, corresponding to cumulative new reservoir surface areas of 161 and 60 ha yr-1, for the GPCGA and the CRCGA, respectively. In terms of reservoir locations relative to aquifer status, after 1996, 84.5% of 309 total reservoirs constructed in the GPCGA and 91.0% of 78 in the CRCGA were located in areas with remaining saturated aquifer thicknesses of 50% or less. The majority of new reservoirs (74% in the GPCGA and 63% in the CRCGA) were constructed on previously productive cropland. The next most common land use, representing 11% and 15% of new reservoirs constructed in the GPCGA and CRCGA, respectively, was the combination of a field edge and a ditch, stream, or other low-lying area. Less than 10% of post-1996 reservoirs were constructed on predominately low-lying land, and the use of such lands decreased in both critical groundwater areas during the past 20 years. These disparities in reservoir construction rates, locations, and prior land uses is likely due to groundwater declines being first observed in the GPCGA as well as the existence of two large-scale river diversion projects under construction in the GPCGA that feature on-farm storage as a means to offset groundwater use.

3D Modeling as Method for Construction and Analysis of Graphic Objects

NASA Astrophysics Data System (ADS)

Kheyfets, A. L.; Vasilieva, V. N.

2017-11-01

The use of 3D modeling when constructing and analyzing perspective projections and shadows is considered. The creation of photorealistic image is shown. The perspective of the construction project and characterization of its image are given as an example. The authors consider the construction of a dynamic block as a means of graphical information storage and automation of geometric constructions. The example of the dynamic block construction at creating a truss node is demonstrated. The constructions are considered as applied to the Auto-CAD software. The paper is aimed at improving the graphic methods of architectural design and improving the educational process when training the Bachelor’s degree students majoring in construction.

Methodology discourses as boundary work in the construction of engineering education.

PubMed

Beddoes, Kacey

2014-04-01

Engineering education research is a new field that emerged in the social sciences over the past 10 years. This analysis of engineering education research demonstrates that methodology discourses have played a central role in the construction and development of the field of engineering education, and that they have done so primarily through boundary work. This article thus contributes to science and technology studies literature by examining the role of methodology discourses in an emerging social science field. I begin with an overview of engineering education research before situating the case within relevant bodies of literature on methodology discourses and boundary work. I then identify two methodology discourses--rigor and methodological diversity--and discuss how they contribute to the construction and development of engineering education research. The article concludes with a discussion of how the findings relate to prior research on methodology discourses and boundary work and implications for future research.

The quasi-biennial variation in the geomagnetic field: a global characteristics analysis

NASA Astrophysics Data System (ADS)

Ou, Jiaming; Du, Aimin

2016-04-01

The periodicity of 1.5-3 years, namely the quasi-biennial oscillation (QBO), has been identified in the solar, geophysical, and atmospheric variability. Sugiura (1976) investigated the observatory annual means over 1900-1970 and confirmed the QBO in the geomagnetic field. At present, studying the quasi-biennial oscillation becomes substantial for separating the internal/external parts in the geomagnetic observations. For the internal field, two typical periodicities, namely the 6-year oscillation in the geomagnetic secular acceleration (SA) and the geomagnetic jerk (occurs in 1-2 years), have close period to the QBO. Recently, a global quasi-biennial fluctuation was identified in the geomagnetic core field model (Silva et al., 2012). Silva et al. speculated this 2.5 years signal to either external source remaining in the core field model or consequence of the methods used to construct the model. As more high-quality data from global observatories are available, it is a good opportunity to characterize the geomagnetic QBO in the global range. In this paper, we investigate the QBO in the observatory monthly geomagnetic field X, Y, and Z components spanning 1985-2010. We employ the observatory hourly means database from the World Data Center for Geomagnetism (WDC) for the investigation. Wavelet analysis is used to detect and identify the QBO, while Fast Fourier Transform (FFT) analysis to obtain the statistics of the QBO. We apply the spherical harmonic analysis on QBO's amplitude, in order to quantify and separate internal and external sources. Three salient periods respectively at 2.9, 2.2, and 1.7 years, are identified in the amplitude spectrum over 1988-2008. The oscillation with the period of ~2.2 years is most prominent in all field components and further studied. In the X component the QBO is attenuated towards the polar regions, while in the Z component the amplitude of QBO increases with increasing of the geomagnetic latitude. At the high latitudes, the QBO exhibits distinct anisotropic in the local time distribution. The QBO of the X and Z components are both stronger over LT 00:00-06:00. The results of spherical harmonic analysis indicate that the QBO is mainly contributed by the external sources. The QBO is highly correlated with various parameters of solar activity, solar wind at 1AU, and geomagnetic activity. Reference 1. Sugiura, M. (1976). Quasi-biennial geomagnetic variation caused by the Sun. Geophys. Res. Lett., 3(11), 643-646. 2. Silva, L., Jackson, L., and Mound, J., (2012), Assessing the importance and expression of the 6 year geomagnetic oscillation, J. Geophys. Res.: Solid Earth (1978-2012), 117.

Constructing Synoptic Maps of Stratospheric Column Ozone from HALOE, SAGE and Balloonsonde Data Using Potential Vorticity Isentropic Coordinate Transformations

NASA Technical Reports Server (NTRS)

Hollandsworth, Stacey M.; Schoeberl, Mark R.; Morris, Gary A.; Long, Craig; Zhou, Shuntai; Miller, Alvin J.

1999-01-01

In this study we utilize potential vorticity - isentropic (PVI) coordinate transformations as a means of combining ozone data from different sources to construct daily, synthetic three-dimensional ozone fields. This methodology has been used successfully to reconstruct ozone maps in particular regions from aircraft data over the period of the aircraft campaign. We expand this method to create high-resolution daily global maps of profile ozone data, particularly in the lower stratosphere, where high-resolution ozone data are sparse. Ozone climatologies in PVI-space are constructed from satellite-based SAGE II and UARS/HALOE data, both of which-use solar occultation techniques to make high vertical resolution ozone profile measurements, but with low spatial resolution. A climatology from ground-based balloonsonde data is also created. The climatologies are used to establish the relationship between ozone and dynamical variability, which is defined by the potential vorticity (in the form of equivalent latitude) and potential temperature fields. Once a PVI climatology has been created from data taken by one or more instruments, high-resolution daily profile ozone field estimates are constructed based solely on the PVI fields, which are available on a daily basis from NCEP analysis. These profile ozone maps could be used for a variety of applications, including use in conjunction with total ozone maps to create a daily tropospheric ozone product, as input to forecast models, or as a tool for validating independent ozone measurements when correlative data are not available. This technique is limited to regions where the ozone is a long-term tracer and the flow is adiabatic. We evaluate the internal consistency of the technique by transforming the ozone back to physical space and comparing to the original profiles. Biases in the long-term average of the differences are used to identify regions where the technique is consistently introducing errors. Initial results show the technique is useful in the lower stratosphere at most latitudes throughout the year,and in the winter hemisphere in the middle stratosphere. The results are problematic in the summer hemisphere middle stratosphere due to increased ozone photochemistry and weak PV gradients. Alternate techniques in these regions will be discussed. An additional limitation is the quality and resolution of the meteorological data.

Self-Authoring Gender outside the Binary: A Narrative Analysis of (Trans)gender Undergraduates

ERIC Educational Resources Information Center

Ashton, Kasey

2013-01-01

This narrative inquiry explored how transgender college students construct, experience, and make meaning of gender. Gender is not constructed or understood in isolation; it is therefore essential to consider how personal cognition intersects with and is influenced by an internal sense of self and relationships with others when exploring how…

Monthly Maps of Sea Surface Height in the North Atlantic and Zonal Indices for the Gulf Stream Using TOPEX/Poseidon Altimeter Data

NASA Technical Reports Server (NTRS)

Singh, Sandipa; Kelly, Kathryn A.

1997-01-01

Monthly Maps of sea surface height are constructed for the North Atlantic Ocean using TOPEX/Poseidon altimeter data. Mean sea surface height is reconstructed using a weighted combination of historical, hydrographic data and a synthetic mean obtained by fitting a Gaussian model of the Gulf Stream jet to altimeter data. The resultant mean shows increased resolution over the hydrographic mean, and incorporates recirculation information that is absent in the synthetic mean. Monthly maps, obtained by adding the mean field to altimeter sea surface height residuals, are used to derive a set of zonal indices that describe the annual cycle of meandering as well as position and strength of the Gulf Stream.

Using the Biodatamation(TM) strategy to learn introductory college biology: Value-added effects on selected students' conceptual understanding and conceptual integration of the processes of photosynthesis and cellular respiration

NASA Astrophysics Data System (ADS)

Reuter, Jewel Jurovich

The purpose of this exploratory research was to study how students learn photosynthesis and cellular respiration and to determine the value added to the student's learning by each of the three technology-scaffolded learning strategy components (animated concept presentations and WebQuest-style activities, data collection, and student-constructed animations) of the BioDatamation(TM) (BDM) Program. BDM learning strategies utilized the Theory of Interacting Visual Fields(TM) (TIVF) (Reuter & Wandersee, 2002a, 2002b; 2003a, 2003b) which holds that meaningful knowledge is hierarchically constructed using the past, present, and future visual fields, with visual metacognitive components that are derived from the principles of Visual Behavior (Jones, 1995), Human Constructivist Theory (Mintzes & Wandersee, 1998a), and Visual Information Design Theory (Tufte, 1990, 1997, 2001). Student alternative conceptions of photosynthesis and cellular respiration were determined by the item analysis of 263,267 Biology Advanced Placement Examinations and were used to develop the BDM instructional strategy and interview questions. The subjects were 24 undergraduate students of high and low biology prior knowledge enrolled in an introductory-level General Biology course at a major research university in the Deep South. Fifteen participants received BDM instruction which included original and innovative learning materials and laboratories in 6 phases; 8 of the 15 participants were the subject of in depth, extended individual analysis. The other 9 participants received traditional, non-BDM instruction. Interviews which included participants' creation of concept maps and visual field diagrams were conducted after each phase. Various content analyses, including Chi's Verbal Analysis and quantitizing/qualitizing were used for data analysis. The total value added to integrative knowledge during BDM instruction with the three visual fields was an average increase of 56% for cellular respiration and 62% increase for photosynthesis knowledge, improved long-term memory of concepts, and enhanced biological literacy to the multidimensional level, as determined by the BSCS literacy model. WebQuest-style activities and data collection provided for animated prior knowledge in the past visual field, and detailed content knowledge construction in the present visual field. During student construction of animated presentations, layering required participants to think by rearranging words and images for improved hierarchical organization of knowledge with real-life applications.

The Use of Lesson Study Combined with Content Representation in the Planning of Physics Lessons During Field Practice to Develop Pedagogical Content Knowledge

NASA Astrophysics Data System (ADS)

Juhler, Martin Vogt

2016-08-01

Recent research, both internationally and in Norway, has clearly expressed concerns about missing connections between subject-matter knowledge, pedagogical competence and real-life practice in schools. This study addresses this problem within the domain of field practice in teacher education, studying pre-service teachers' planning of a Physics lesson. Two means of intervention were introduced. The first was lesson study, which is a method for planning, carrying out and reflecting on a research lesson in detail with a learner and content-centered focus. This was used in combination with a second means, content representations, which is a systematic tool that connects overall teaching aims with pedagogical prompts. Changes in teaching were assessed through the construct of pedagogical content knowledge (PCK). A deductive coding analysis was carried out for this purpose. Transcripts of pre-service teachers' planning of a Physics lesson were coded into four main PCK categories, which were thereafter divided into 16 PCK sub-categories. The results showed that the intervention affected the pre-service teachers' potential to start developing PCK. First, they focused much more on categories concerning the learners. Second, they focused far more uniformly in all of the four main categories comprising PCK. Consequently, these differences could affect their potential to start developing PCK.

Mean Field Analysis of Large-Scale Interacting Populations of Stochastic Conductance-Based Spiking Neurons Using the Klimontovich Method

NASA Astrophysics Data System (ADS)

Gandolfo, Daniel; Rodriguez, Roger; Tuckwell, Henry C.

2017-03-01

We investigate the dynamics of large-scale interacting neural populations, composed of conductance based, spiking model neurons with modifiable synaptic connection strengths, which are possibly also subjected to external noisy currents. The network dynamics is controlled by a set of neural population probability distributions (PPD) which are constructed along the same lines as in the Klimontovich approach to the kinetic theory of plasmas. An exact non-closed, nonlinear, system of integro-partial differential equations is derived for the PPDs. As is customary, a closing procedure leads to a mean field limit. The equations we have obtained are of the same type as those which have been recently derived using rigorous techniques of probability theory. The numerical solutions of these so called McKean-Vlasov-Fokker-Planck equations, which are only valid in the limit of infinite size networks, actually shows that the statistical measures as obtained from PPDs are in good agreement with those obtained through direct integration of the stochastic dynamical system for large but finite size networks. Although numerical solutions have been obtained for networks of Fitzhugh-Nagumo model neurons, which are often used to approximate Hodgkin-Huxley model neurons, the theory can be readily applied to networks of general conductance-based model neurons of arbitrary dimension.

Predicting temperature drop rate of mass concrete during an initial cooling period using genetic programming

NASA Astrophysics Data System (ADS)

Bhattarai, Santosh; Zhou, Yihong; Zhao, Chunju; Zhou, Huawei

2018-02-01

Thermal cracking on concrete dams depends upon the rate at which the concrete is cooled (temperature drop rate per day) within an initial cooling period during the construction phase. Thus, in order to control the thermal cracking of such structure, temperature development due to heat of hydration of cement should be dropped at suitable rate. In this study, an attempt have been made to formulate the relation between cooling rate of mass concrete with passage of time (age of concrete) and water cooling parameters: flow rate and inlet temperature of cooling water. Data measured at summer season (April-August from 2009 to 2012) from recently constructed high concrete dam were used to derive a prediction model with the help of Genetic Programming (GP) software “Eureqa”. Coefficient of Determination (R) and Mean Square Error (MSE) were used to evaluate the performance of the model. The value of R and MSE is 0.8855 and 0.002961 respectively. Sensitivity analysis was performed to evaluate the relative impact on the target parameter due to input parameters. Further, testing the proposed model with an independent dataset those not included during analysis, results obtained from the proposed GP model are close enough to the real field data.

Spatial distribution of organic pollutants in industrial construction and demolition waste and their mutual interaction on an abandoned pesticide manufacturing plant.

PubMed

Huang, Sheng; Zhao, Xin; Sun, Yanqiu; Ma, Jianli; Gao, Xiaofeng; Xie, Tian; Xu, Dongsheng; Yu, Yi; Zhao, Youcai

2016-04-01

A comprehensive field investigation of organic pollutants was examined in industrial construction and demolition waste (ICDW) inside an abandoned pesticide manufacturing plant. Concentrations of eight types of pesticides, a metabolite and two intermediates were studied. The ICDW was under severe and long-term contamination by organophosphorus, intermediates and pyrethroid pesticide with mean concentrations of 23,429, 3538 and 179.4 mg kg(-1), respectively. FT-IR analysis suggested that physical absorption and chemical bonding were their mutual interaction forms. Patterns of total pesticide spatial distribution showed good correlations with manufacturing processes spreading all over the plant both in enclosed workshops and in residues randomly dumped outside, while bricks and coatings were the most vulnerable to pollutants. Ultimately the fate of the OPPs was diversified as the immersion of ICDW in water largely transferred the pollutants into aquatic systems while exposure outside did not largely lead to pesticide degradation. The adoption of centralized collections for the disposal of wastes could only eliminate part of the contaminated ICDW, probably due to lack of knowledge and criteria. Correlation matrix and cluster analysis indicated that regulated disposal and management of polluted ICDW was effective, thus presenting the requirement for its appropriate disposal.

Field theories and fluids for an interacting dark sector

NASA Astrophysics Data System (ADS)

Carrillo González, Mariana; Trodden, Mark

2018-02-01

We consider the relationship between fluid models of an interacting dark sector and the field theoretical models that underlie such descriptions. This question is particularly important in light of suggestions that such interactions may help alleviate a number of current tensions between different cosmological datasets. We construct consistent field theory models for an interacting dark sector that behave exactly like the coupled fluid ones, even at the level of linear perturbations, and can be trusted deep in the nonlinear regime. As a specific example, we focus on the case of a Dirac, Born-Infeld (DBI) field conformally coupled to a quintessence field. We show that the fluid linear regime breaks before the field gradients become large; this means that the field theory is valid inside a large region of the fluid nonlinear regime.

Analysis of field permeability and laboratory shear stress for Western Kentucky Parkway, milepost 18.240 to milepost 25.565, Caldwell-Hopkins counties

DOT National Transportation Integrated Search

2003-02-01

This report lists and discusses results of field permeability tests and laboratory shear tests on samples from a construction project on the Western Kentucky Parkway in Caldwell-Hopkins Counties. Approximately 6,500 tons of asphaltic concrete overlay...

Development and psychometric properties of the Maastricht Personal Autonomy Questionnaire (MPAQ) in older adults with a chronic physical illness.

PubMed

Mars, Godelief M J; van Eijk, Jacques Th M; Post, Marcel W M; Proot, Ireen M; Mesters, Ilse; Kempen, Gertrudis I J M

2014-08-01

To develop and test the Maastricht Personal Autonomy Questionnaire (MPAQ), an instrument measuring personal autonomy of older adults with a chronic physical illness in accordance with their experience of autonomy. Achievement of personal autonomy is conceptualized as correspondence between the way people's lives are actually arranged and the way people want to arrange their lives. A field test was conducted in three waves (n = 412, n = 125 and n = 244) among a random sample of people older than 59 years with either chronic obstructive pulmonary disease or diabetes mellitus. Construct validity, reproducibility and responsiveness were evaluated. The MPAQ entailing 16 items consists of three scales: degree of (personal) autonomy, working on autonomy and dilemmas. Construct validity was largely supported by confirmatory factor analysis and correlations between the MPAQ and other instruments. Intraclass correlation coefficients ranged from 0.61 to 0.80 and SRDsgroup from 0.10 to 0.13. Mean change was larger (0.54) than was SRDgroup (0.11) in patients who had deteriorated, but smaller in patients who had improved (0.07). The MPAQ has good content and construct validity and moderate reproducibility. Responsiveness is weak, although better for deterioration than for improvement.

The Specific Level of Functioning Scale: construct validity, internal consistency and factor structure in a large Italian sample of people with schizophrenia living in the community.

PubMed

Mucci, Armida; Rucci, Paola; Rocca, Paola; Bucci, Paola; Gibertoni, Dino; Merlotti, Eleonora; Galderisi, Silvana; Maj, Mario

2014-10-01

The study aimed to assess the construct validity, internal consistency and factor structure of the Specific Levels of Functioning Scale (SLOF), a multidimensional instrument assessing real life functioning. The study was carried out in 895 Italian people with schizophrenia, all living in the community and attending the outpatient units of 26 university psychiatric clinics and/or community mental health departments. The construct validity of the SLOF was analyzed by means of the multitrait-multimethod approach, using the Personal and Social Performance (PSP) Scale as the gold standard. The factor structure of the SLOF was examined using both an exploratory principal component analysis and a confirmatory factor analysis. The six factors identified using exploratory principal component analysis explained 57.1% of the item variance. The examination of the multitrait-multimethod matrix revealed that the SLOF factors had high correlations with PSP factors measuring the same constructs and low correlations with PSP factors measuring different constructs. The confirmatory factor analysis (CFA) corroborated the 6-factor structure reported in the original validation study. Loadings were all significant and ranged from a minimum of 0.299 to a maximum of 0.803. The CFA model was adequately powered and had satisfactory goodness of fit indices (comparative fit index=0.927, Tucker-Lewis index=0.920 and root mean square error of approximation=0.047, 95% CI 0.045-0.049). The present study confirms, in a large sample of Italian people with schizophrenia living in the community, that the SLOF is a reliable and valid instrument for the assessment of social functioning. It has good construct validity and internal consistency, and a well-defined factor structure. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of Jefferson Road stormwater-detention basin on loads and concentrations of selected chemical constituents in East Branch of Allen Creek at Pittsford, Monroe County, New York

USGS Publications Warehouse

Sherwood, Donald A.

2004-01-01

Discharge and water-quality data collection at East Branch Allen Creek from 1990 through 2000 provide a basis for estimating the effect of the Jefferson Road detention basin on loads and concentrations of chemical constituents downstream from the basin. Mean monthly flow for the 5 years prior to construction of the detention basin (8.71 ft3/s) was slightly lower than after (9.08 ft3/s). The slightly higher mean monthly flow after basin construction may have been influenced by the peak flow for the period of record that occurred in July 1998 or variations in flow diverted from the canal. No statistically significant difference in average monthly mean flow before and after basin installation was indicated.Total phosphorus was the only constituent to show no months with significant differences in load after basin construction. Several constituents showed months with significantly smaller loads after basin construction than before, whereas some constituents showed certain months with smaller and some months with greater loads, after basin construction. Statistical analysis of the "mean monthly load" for all months before and all months after construction of the detention basin showed only one constituent (ammonia + organic nitrogen) with a significantly lower load after construction and none with higher loads.Median concentrations of ammonia + organic nitrogen showed a statistically significant decrease (from 0.78 mg/L to 0.60 mg/L) after basin installation, as did nitrite + nitrate (from 1.50 mg/L to 0.96 mg/L); in contrast, the median concentration of dissolved chloride increased from 95.5 mg/L before basin installation to 109 mg/L thereafter. A trend analysis of constituent concentrations before and after installation of the detention basin showed that total phosphorus had a downward trend after installation.Analysis of the data collected at East Branch Allen Creek indicates that the Jefferson Road detention basin, in some cases, provides an improvement (reduction) in loads of some constituents. These results are uncertain, however, because hydrologic conditions before basin installation differed from those in the 5 years that followed, and because inflow from the Erie-Barge canal may alter the water quality in the 1-mi reach between the basin outflow and the gaging station.

Non-degeneracy, Mean Field Equations and the Onsager Theory of 2D Turbulence

NASA Astrophysics Data System (ADS)

Bartolucci, Daniele; Jevnikar, Aleks; Lee, Youngae; Yang, Wen

2018-04-01

The understanding of some large energy, negative specific heat states in the Onsager description of 2D turbulence seem to require the analysis of a subtle open problem about bubbling solutions of the mean field equation. Motivated by this application we prove that, under suitable non-degeneracy assumptions on the associated m-vortex Hamiltonian, the m-point bubbling solutions of the mean field equation are non-degenerate as well. Then we deduce that the Onsager mean field equilibrium entropy is smooth and strictly convex in the high energy regime on domains of second kind.

Hopping and the Stokes–Einstein relation breakdown in simple glass formers

PubMed Central

Charbonneau, Patrick; Jin, Yuliang; Parisi, Giorgio; Zamponi, Francesco

2014-01-01

One of the most actively debated issues in the study of the glass transition is whether a mean-field description is a reasonable starting point for understanding experimental glass formers. Although the mean-field theory of the glass transition—like that of other statistical systems—is exact when the spatial dimension d→∞, the evolution of systems properties with d may not be smooth. Finite-dimensional effects could dramatically change what happens in physical dimensions, d=2,3. For standard phase transitions finite-dimensional effects are typically captured by renormalization group methods, but for glasses the corrections are much more subtle and only partially understood. Here, we investigate hopping between localized cages formed by neighboring particles in a model that allows to cleanly isolate that effect. By bringing together results from replica theory, cavity reconstruction, void percolation, and molecular dynamics, we obtain insights into how hopping induces a breakdown of the Stokes–Einstein relation and modifies the mean-field scenario in experimental systems. Although hopping is found to supersede the dynamical glass transition, it nonetheless leaves a sizable part of the critical regime untouched. By providing a constructive framework for identifying and quantifying the role of hopping, we thus take an important step toward describing dynamic facilitation in the framework of the mean-field theory of glasses. PMID:25288722

Hopping and the Stokes-Einstein relation breakdown in simple glass formers.

PubMed

Charbonneau, Patrick; Jin, Yuliang; Parisi, Giorgio; Zamponi, Francesco

2014-10-21

One of the most actively debated issues in the study of the glass transition is whether a mean-field description is a reasonable starting point for understanding experimental glass formers. Although the mean-field theory of the glass transition--like that of other statistical systems--is exact when the spatial dimension d → ∞, the evolution of systems properties with d may not be smooth. Finite-dimensional effects could dramatically change what happens in physical dimensions,d = 2, 3. For standard phase transitions finite-dimensional effects are typically captured by renormalization group methods, but for glasses the corrections are much more subtle and only partially understood. Here, we investigate hopping between localized cages formed by neighboring particles in a model that allows to cleanly isolate that effect. By bringing together results from replica theory, cavity reconstruction, void percolation, and molecular dynamics, we obtain insights into how hopping induces a breakdown of the Stokes-Einstein relation and modifies the mean-field scenario in experimental systems. Although hopping is found to supersede the dynamical glass transition, it nonetheless leaves a sizable part of the critical regime untouched. By providing a constructive framework for identifying and quantifying the role of hopping, we thus take an important step toward describing dynamic facilitation in the framework of the mean-field theory of glasses.

Exponential stability of impulsive stochastic genetic regulatory networks with time-varying delays and reaction-diffusion

DOE PAGES

Cao, Boqiang; Zhang, Qimin; Ye, Ming

2016-11-29

We present a mean-square exponential stability analysis for impulsive stochastic genetic regulatory networks (GRNs) with time-varying delays and reaction-diffusion driven by fractional Brownian motion (fBm). By constructing a Lyapunov functional and using linear matrix inequality for stochastic analysis we derive sufficient conditions to guarantee the exponential stability of the stochastic model of impulsive GRNs in the mean-square sense. Meanwhile, the corresponding results are obtained for the GRNs with constant time delays and standard Brownian motion. Finally, an example is presented to illustrate our results of the mean-square exponential stability analysis.

Validation of a proposal for evaluating hospital infection control programs.

PubMed

Silva, Cristiane Pavanello Rodrigues; Lacerda, Rúbia Aparecida

2011-02-01

To validate the construct and discriminant properties of a hospital infection prevention and control program. The program consisted of four indicators: technical-operational structure; operational prevention and control guidelines; epidemiological surveillance system; and prevention and control activities. These indicators, with previously validated content, were applied to 50 healthcare institutions in the city of São Paulo, Southeastern Brazil, in 2009. Descriptive statistics were used to characterize the hospitals and indicator scores, and Cronbach's α coefficient was used to evaluate the internal consistency. The discriminant validity was analyzed by comparing indicator scores between groups of hospitals: with versus without quality certification. The construct validity analysis was based on exploratory factor analysis with a tetrachoric correlation matrix. The indicators for the technical-operational structure and epidemiological surveillance presented almost 100% conformity in the whole sample. The indicators for the operational prevention and control guidelines and the prevention and control activities presented internal consistency ranging from 0.67 to 0.80. The discriminant validity of these indicators indicated higher and statistically significant mean conformity scores among the group of institutions with healthcare certification or accreditation processes. In the construct validation, two dimensions were identified for the operational prevention and control guidelines: recommendations for preventing hospital infection and recommendations for standardizing prophylaxis procedures, with good correlation between the analysis units that formed the guidelines. The same was found for the prevention and control activities: interfaces with treatment units and support units were identified. Validation of the measurement properties of the hospital infection prevention and control program indicators made it possible to develop a tool for evaluating these programs in an ethical and scientific manner in order to obtain a quality diagnosis in this field.

Cumulative impacts of oil fields on northern Alaskan landscapes

USGS Publications Warehouse

Walker, D.A.; Webber, P.J.; Binnian, Emily F.; Everett, K.R.; Lederer, N.D.; Nordstrand, E.A.; Walker, M.D.

1987-01-01

Proposed further developments on Alaska's Arctic Coastal Plain raise questions about cumulative effects on arctic tundra ecosystems of development of multiple large oil fields. Maps of historical changes to the Prudhoe Bay Oil Field show indirect impacts can lag behind planned developments by many years and the total area eventually disturbed can greatly exceed the planned area of construction. For example, in the wettest parts of the oil field (flat thaw-lake plains), flooding and thermokarst covered more than twice the area directly affected by roads and other construction activities. Protecting critical wildlife habitat is the central issue for cumulative impact analysis in northern Alaska. Comprehensive landscape planning with the use of geographic information system technology and detailed geobotanical maps can help identify and protect areas of high wildlife use.

ADM Analysis of gravity models within the framework of bimetric variational formalism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Golovnev, Alexey; Karčiauskas, Mindaugas; Nyrhinen, Hannu J., E-mail: agolovnev@yandex.ru, E-mail: mindaugas.karciauskas@helsinki.fi, E-mail: hannu.nyrhinen@helsinki.fi

2015-05-01

Bimetric variational formalism was recently employed to construct novel bimetric gravity models. In these models an affine connection is generated by an additional tensor field which is independent of the physical metric. In this work we demonstrate how the ADM decomposition can be applied to study such models and provide some technical intermediate details. Using ADM decomposition we are able to prove that a linear model is unstable as has previously been indicated by perturbative analysis. Moreover, we show that it is also very difficult if not impossible to construct a non-linear model which is ghost-free within the framework ofmore » bimetric variational formalism. However, we demonstrate that viable models are possible along similar lines of thought. To this end, we consider a set up in which the affine connection is a variation of the Levi-Civita one. As a proof of principle we construct a gravity model with a massless scalar field obtained this way.« less

[The construction process of managerial profile competencies for nurse coordinators in the hospital field].

PubMed

Manenti, Simone Alexandra; Ciampone, Maria Helena Trench; Mira, Vera Lucia; Minami, Lígia Fumiko; Soares, Jaqueline Maria Sousa

2012-06-01

The objective of this study was to construct a profile of managerial competencies, based on the consensus of nurse coordinators in the field. This study was developed in a philanthropic hospital in São Paulo, following the research-action model, and included 13 nurse coordinators as participants. The data collection was performed using the focal group technique. Data analysis was performed using the theoretical frameworks related to the working process and managerial competencies. The results identified the greater emphasis assigned to the competencies related to the mentor, coordinator and director roles. It was, therefore, possible to construct a professional development plan that is based on competencies in the technical, ethical-political, and communicative domains, as well as the development of citizenship. The analysis of the managerial working process and the study of the competencies within the managerial environment were shown to be important, because they highlighted the professionals' need to improve, thus fulfilling personal, professional, and organizational demands.

Cost-Effectiveness Analysis of Surface Flow Constructed Wetlands (SFCW) for Nutrient Reduction in Drainage Discharge from Agricultural Fields in Denmark.

PubMed

Gachango, F G; Pedersen, S M; Kjaergaard, C

2015-12-01

Constructed wetlands have been proposed as cost-effective and more targeted technologies in the reduction of nitrogen and phosphorous water pollution in drainage losses from agricultural fields in Denmark. Using two pig farms and one dairy farm situated in a pumped lowland catchment as case studies, this paper explores the feasibility of implementing surface flow constructed wetlands (SFCW) based on their cost effectiveness. Sensitivity analysis is conducted by varying the cost elements of the wetlands in order to establish the most cost-effective scenario and a comparison with the existing nutrients reduction measures carried out. The analyses show that the cost effectiveness of the SFCW is higher in the drainage catchments with higher nutrient loads. The range of the cost effectiveness ratio on nitrogen reduction differs distinctively with that of catch crop measure. The study concludes that SFCW could be a better optimal nutrients reduction measure in drainage catchments characterized with higher nutrient loads.

Paired quantum Hall states on noncommutative two-tori

NASA Astrophysics Data System (ADS)

Marotta, Vincenzo; Naddeo, Adele

2010-08-01

By exploiting the notion of Morita equivalence for field theories on noncommutative tori and choosing rational values of the noncommutativity parameter θ (in appropriate units), a one-to-one correspondence between an Abelian noncommutative field theory (NCFT) and a non-Abelian theory of twisted fields on ordinary space can be established. Starting from this general result, we focus on the conformal field theory (CFT) describing a quantum Hall fluid (QHF) at paired states fillings ν=mp/m+2 Cristofano et al. (2000) [1], recently obtained by means of m-reduction procedure, and show that it is the Morita equivalent of a NCFT. In this way we extend the construction proposed in Marotta and Naddeo (2008) [2] for the Jain series ν=>m2p/m+1. The case m=2 is explicitly discussed and the role of noncommutativity in the physics of quantum Hall bilayers is emphasized. Our results represent a step forward the construction of a new effective low energy description of certain condensed matter phenomena and help to clarify the relationship between noncommutativity and quantum Hall fluids.

Validity: One Word with a Plurality of Meanings

ERIC Educational Resources Information Center

St-Onge, Christina; Young, Meredith; Eva, Kevin W.; Hodges, Brian

2017-01-01

Validity is one of the most debated constructs in our field; debates abound about what is legitimate and what is not, and the word continues to be used in ways that are explicitly disavowed by current practice guidelines. The resultant tensions have not been well characterized, yet their existence suggests that different uses may maintain some…

On the Making and Taking of Professionalism in the Further Education Workplace

ERIC Educational Resources Information Center

Gleeson, Denis; Davies, Jenifer; Wheeler, Eunice

2005-01-01

This paper examines the changing nature of professional practice in English further education. At a time when neo-liberal reform has significantly impacted on this under-researched and over-market-tested sector, little is known about who its practitioners are and how they construct meaning in their work. Sociological interest in the field has…

An MHD Dynamo Experiment.

NASA Astrophysics Data System (ADS)

O'Connell, R.; Forest, C. B.; Plard, F.; Kendrick, R.; Lovell, T.; Thomas, M.; Bonazza, R.; Jensen, T.; Politzer, P.; Gerritsen, W.; McDowell, M.

1997-11-01

A MHD experiment is being constructed which will have the possibility of showing dynamo action: the self--generation of currents from fluid motion. The design allows sufficient experimental flexibility and diagnostic access to study a variety of issues central to dynamo theory, including mean--field electrodynamics and saturation (backreaction physics). Initially, helical flows required for dynamo action will be driven by propellers embedded in liquid sodium. The flow fields will first be measured using laser doppler velocimetry in a water experiment with an identical fluid Reynolds number. The magnetic field evolution will then be predicted using a MHD code, replacing the water with sodium; if growing magnetic fields are found, the experiment will be repeated with sodium.

Subgrid-scale stresses and scalar fluxes constructed by the multi-scale turnover Lagrangian map

NASA Astrophysics Data System (ADS)

AL-Bairmani, Sukaina; Li, Yi; Rosales, Carlos; Xie, Zheng-tong

2017-04-01

The multi-scale turnover Lagrangian map (MTLM) [C. Rosales and C. Meneveau, "Anomalous scaling and intermittency in three-dimensional synthetic turbulence," Phys. Rev. E 78, 016313 (2008)] uses nested multi-scale Lagrangian advection of fluid particles to distort a Gaussian velocity field and, as a result, generate non-Gaussian synthetic velocity fields. Passive scalar fields can be generated with the procedure when the fluid particles carry a scalar property [C. Rosales, "Synthetic three-dimensional turbulent passive scalar fields via the minimal Lagrangian map," Phys. Fluids 23, 075106 (2011)]. The synthetic fields have been shown to possess highly realistic statistics characterizing small scale intermittency, geometrical structures, and vortex dynamics. In this paper, we present a study of the synthetic fields using the filtering approach. This approach, which has not been pursued so far, provides insights on the potential applications of the synthetic fields in large eddy simulations and subgrid-scale (SGS) modelling. The MTLM method is first generalized to model scalar fields produced by an imposed linear mean profile. We then calculate the subgrid-scale stress, SGS scalar flux, SGS scalar variance, as well as related quantities from the synthetic fields. Comparison with direct numerical simulations (DNSs) shows that the synthetic fields reproduce the probability distributions of the SGS energy and scalar dissipation rather well. Related geometrical statistics also display close agreement with DNS results. The synthetic fields slightly under-estimate the mean SGS energy dissipation and slightly over-predict the mean SGS scalar variance dissipation. In general, the synthetic fields tend to slightly under-estimate the probability of large fluctuations for most quantities we have examined. Small scale anisotropy in the scalar field originated from the imposed mean gradient is captured. The sensitivity of the synthetic fields on the input spectra is assessed by using truncated spectra or model spectra as the input. Analyses show that most of the SGS statistics agree well with those from MTLM fields with DNS spectra as the input. For the mean SGS energy dissipation, some significant deviation is observed. However, it is shown that the deviation can be parametrized by the input energy spectrum, which demonstrates the robustness of the MTLM procedure.

On the energy-momentum tensor in Moyal space

DOE PAGES

Balasin, Herbert; Blaschke, Daniel N.; Gieres, François; ...

2015-06-26

We study the properties of the energy-momentum tensor of gauge fields coupled to matter in non-commutative (Moyal) space. In general, the non-commutativity affects the usual conservation law of the tensor as well as its transformation properties (gauge covariance instead of gauge invariance). It is known that the conservation of the energy-momentum tensor can be achieved by a redefinition involving another starproduct. Furthermore, for a pure gauge theory it is always possible to define a gauge invariant energy-momentum tensor by means of a Wilson line. We show that the latter two procedures are incompatible with each other if couplings of gaugemore » fields to matter fields (scalars or fermions) are considered: The gauge invariant tensor (constructed via Wilson line) does not allow for a redefinition assuring its conservation, and vice-versa the introduction of another star-product does not allow for gauge invariance by means of a Wilson line.« less

The Search for an Effective Clinical Behavior Analysis: The Nonlinear Thinking of Israel Goldiamond

ERIC Educational Resources Information Center

Layng, T. V. Joe

2009-01-01

This paper has two purposes; the first is to reintroduce Goldiamond's constructional approach to clinical behavior analysis and to the field of behavior analysis as a whole, which, unfortunately, remains largely unaware of his nonlinear functional analysis and its implications. The approach is not simply a set of clinical techniques; instead it…

"I Mean, We're Guys": Constructing Gender at an All-Male Trade School

ERIC Educational Resources Information Center

Arbeit, Miriam R.; Hershberg, Rachel M.; Johnson, Sara K.; Lerner, Jacqueline V.; Lerner, Richard M.

2017-01-01

For young men, the transition to adulthood may be a time of heightened adherence to traditional gender roles and norms of masculinity. However, recent research with young men in gender-specific contexts has indicated that some contexts support a construction of masculinity that is more inclusive. Through a theoretical thematic analysis of…

The Interactional Construction of Identity: An Adolescent with Autism in Interaction with Peers

ERIC Educational Resources Information Center

Bottema-Beutel, Kristen; Smith, Nevin

2013-01-01

Using discourse analytic methodology, this study examines video data collected during a social group intervention designed to promote engagement between teens with autism spectrum disorders (ASDs) and their peers. The analysis focuses on the interactive means by which the participants construct the identity of the group member with an ASD,…

Extending the Constructs of Active Learning: Implications for Teachers' Pedagogy and Practice

ERIC Educational Resources Information Center

Drew, Valerie; Mackie, Lorele

2011-01-01

Active learning is a pedagogical construct widely appealed to within the global discourse of lifelong learning. However, an examination of the literature reveals a lack of clarity and consensus as to its meaning. This article provides a critical analysis of a range of dimensions underpinning the concept of active learning including policy…

Evaluating Students' Abilities to Construct Mathematical Models from Data Using Latent Class Analysis

ERIC Educational Resources Information Center

Brandriet, Alexandra; Rupp, Charlie A.; Lazenby, Katherine; Becker, Nicole M.

2018-01-01

Analyzing and interpreting data is an important science practice that contributes toward the construction of models from data; yet, there is evidence that students may struggle with making meaning of data. The study reported here focused on characterizing students' approaches to analyzing rate and concentration data in the context of method of…

Testing the Construct Validity of Proposed Criteria for "DSM-5" Autism Spectrum Disorder

ERIC Educational Resources Information Center

Mandy, William P. L.; Charman, Tony; Skuse, David H.

2012-01-01

Objective: To use confirmatory factor analysis to test the construct validity of the proposed "DSM-5" symptom model of autism spectrum disorder (ASD), in comparison to alternative models, including that described in "DSM-IV-TR." Method: Participants were 708 verbal children and young persons (mean age, 9.5 years) with mild to severe autistic…

Psychobiological operationalization of RDoC constructs: Methodological and conceptual opportunities and challenges.

PubMed

MacNamara, Annmarie; Phan, K Luan

2016-03-01

NIMH's Research Domain Criteria (RDoC) project seeks to advance the diagnosis, prevention, and treatment of mental disorders by promoting psychobiological research on dimensional constructs that might cut across traditional diagnostic boundaries (Kozak & Cuthbert, ). At the core of this approach is the notion that these dimensional constructs can be assessed across different units of analysis (e.g., genes, physiology, behavior), enriching the constructs and providing more complete explanations of clinical problems. While the conceptual aspects of RDoC have been discussed in several prior papers, its methodological aspects have received comparatively less attention. For example, how to integrate data from different units of analysis has been relatively unclear. Here, we discuss one means of psychobiologically operationalizing RDoC constructs across different units of analysis (the psychoneurometric approach; Yancey et al., ), highlighting ways in which this approach might be refined in future iterations. We conclude that there is much to be learned from this technique; however, greater attention to scale-development methods and to psychometrics will likely benefit this and other methodological approaches to combining measurements across multiple units of analysis. © 2016 Society for Psychophysiological Research.

Walkable Worlds give a Rich Self-Similar Structure to the Real Line

NASA Astrophysics Data System (ADS)

Rosinger, Elemér E.

2010-05-01

It is a rather universal tacit and unquestioned belief—and even more so among physicists—that there is one and only one real line, namely, given by the coodinatisation of Descartes through the usual field R of real numbers. Such a dramatically limiting and thus harmful belief comes, unknown to equally many, from the similarly tacit acceptance of the ancient Archimedean Axiom in Euclid's Geometry. The consequence of that belief is a similar belief in the uniqueness of the coordinatization of the plane by the usual field C of complex numbers, and therefore, of the various spaces, manifolds, etc., be they finite or infinite dimensional, constructed upon the real or complex numbers, including the Hilbert spaces used in Quantum Mechanics. A near total lack of awareness follows therefore about the rich self-similar structure of other possible coordinatisations of the real line, possibilities given by various linearly ordered scalar fields obtained through the ultrapower construction. Such fields contain as a rather small subset the usual field R of real numbers. The concept of walkable world, which has highly intuitive and pragmatic algebraic and geometric meaning, illustrates the mentioned rich self-similar structure.

INTERPRETATION OF THE STRUCTURE FUNCTION OF ROTATION MEASURE IN THE INTERSTELLAR MEDIUM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Siyao; Zhang, Bing, E-mail: syxu@pku.edu.cn, E-mail: zhang@physics.unlv.edu

2016-06-20

The observed structure function (SF) of rotation measure (RM) varies as a broken power-law function of angular scales. The systematic shallowness of its spectral slope is inconsistent with the standard Kolmogorov scaling. This motivates us to examine the statistical analysis on RM fluctuations. The correlations of RM constructed by Lazarian and Pogosyan are demonstrated to be adequate in explaining the observed features of RM SFs through a direct comparison between the theoretically obtained and observationally measured SF results. By segregating the density and magnetic field fluctuations and adopting arbitrary indices for their respective power spectra, we find that when themore » SFs of RM and emission measure have a similar form over the same range of angular scales, the statistics of the RM fluctuations reflect the properties of density fluctuations. RM SFs can be used to evaluate the mean magnetic field along the line of sight, but cannot serve as an informative source on the properties of turbulent magnetic field in the interstellar medium. We identify the spectral break of RM SFs as the inner scale of a shallow spectrum of electron density fluctuations, which characterizes the typical size of discrete electron density structures in the observed region.« less

On the presence of electric currents in the solar atmosphere. I - A theoretical framework

NASA Technical Reports Server (NTRS)

Hagyard, M.; Low, B. C.; Tandberg-Hanssen, E.

1981-01-01

The general magnetic field above the solar photosphere is divided by an elementary analysis based on Ampere's law into two parts: a potential field due to electric currents below the photosphere and a field produced by electric currents above the photosphere combined with the induced mirror currents. The latter, by symmetry, has a set of field lines lying in the plane taken to be the photosphere which may be constructed from given vector magnetograph measurements. These field lines also represent all the information on the electric currents above the photosphere that a magnetograph can provide. Theoretical illustrations are given, and implications for data analysis are discussed.

Mean-field theory of active electrolytes: Dynamic adsorption and overscreening

NASA Astrophysics Data System (ADS)

Frydel, Derek; Podgornik, Rudolf

2018-05-01

We investigate active electrolytes within the mean-field level of description. The focus is on how the double-layer structure of passive, thermalized charges is affected by active dynamics of constituting ions. One feature of active dynamics is that particles adhere to hard surfaces, regardless of chemical properties of a surface and specifically in complete absence of any chemisorption or physisorption. To carry out the mean-field analysis of the system that is out of equilibrium, we develop the "mean-field simulation" technique, where the simulated system consists of charged parallel sheets moving on a line and obeying active dynamics, with the interaction strength rescaled by the number of sheets. The mean-field limit becomes exact in the limit of an infinite number of movable sheets.

Reservoir monitoring and characterization using satellite geodetic data: Interferometric Synthetic Aperture Radar observations from the Krechba field, Algeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vasco, D.W.; Ferretti, Alessandro; Novali, Fabrizio

2008-05-01

Deformation in the material overlying an active reservoir is used to monitor pressure change at depth. A sequence of pressure field estimates, eleven in all, allow us to construct a measure of diffusive travel time throughout the reservoir. The dense distribution of travel time values means that we can construct an exactly linear inverse problem for reservoir flow properties. Application to Interferometric Synthetic Aperture Radar (InSAR) data gathered over a CO{sub 2} injection in Algeria reveals pressure propagation along two northwest trending corridors. An inversion of the travel times indicates the existence of two northwest-trending high permeability zones. The highmore » permeability features trend in the same direction as the regional fault and fracture zones. Model parameter resolution estimates indicate that the features are well resolved.« less

Wavelet-based hierarchical surface approximation from height fields

Treesearch

Sang-Mook Lee; A. Lynn Abbott; Daniel L. Schmoldt

2004-01-01

This paper presents a novel hierarchical approach to triangular mesh generation from height fields. A wavelet-based multiresolution analysis technique is used to estimate local shape information at different levels of resolution. Using predefined templates at the coarsest level, the method constructs an initial triangulation in which underlying object shapes are well...

Development of an economical thin, quiet, long-lasting, high friction surface layer for economical use in Illinois, volume 2 : field construction, field testing, and engineering benefit analysis.

DOT National Transportation Integrated Search

2013-03-01

This project provides techniques to improve hot-mix asphalt (HMA) overlays specifically through the use of : special additives and innovative surfacing technologies with aggregates that are locally available in Illinois. The : ultimate goal is to imp...

Scientific Collaboration in Chinese Nursing Research: A Social Network Analysis Study.

PubMed

Hou, Xiao-Ni; Hao, Yu-Fang; Cao, Jing; She, Yan-Chao; Duan, Hong-Mei

2016-01-01

Collaboration has become very important in research and in technological progress. Coauthorship networks in different fields have been intensively studied as an important type of collaboration in recent years. Yet there are few published reports about collaboration in the field of nursing. This article aimed to reveal the status and identify the key features of collaboration in the field of nursing in China. Using data from the top 10 nursing journals in China from 2003 to 2013, we constructed a nursing scientific coauthorship network using social network analysis. We found that coauthorship was a common phenomenon in the Chinese nursing field. A coauthorship network with 228 subnetworks formed by 1428 nodes was constructed. The network was relatively loose, and most subnetworks were of small scales. Scholars from Shanghai and from military medical system were at the center of the Chinese nursing scientific coauthorship network. We identified the authors' positions and influences according to the research output and centralities of each author. We also analyzed the microstructure and the evolution over time of the maximum subnetwork.

Gott time machines in anti-de Sitter space

NASA Astrophysics Data System (ADS)

Holst, Sören

1996-04-01

In 1991 Gott presented a solution of Einstein's field equations in 2+1 dimensions with λ=0 that contained closed timelike curves ( ctc's). This solution was remarkable because at first it did not seem to be unphysical in any other respect. Later, however, it was shown that Gott's solution is tachyonic in a certain sense. Here the case λ<0 is discussed. We show that it is also possible to construct ctc's in this case, in a way analogous to that used by Gott. We also show a special case of this construction to be tachyonic. λ<0 means that we are dealing with anti-de Sitter space, and since the CTC-construction necessitates some understanding of its structure, a few pages are devoted to this subject.

Mean Field Games for Stochastic Growth with Relative Utility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Minyi, E-mail: mhuang@math.carleton.ca; Nguyen, Son Luu, E-mail: sonluu.nguyen@upr.edu

This paper considers continuous time stochastic growth-consumption optimization in a mean field game setting. The individual capital stock evolution is determined by a Cobb–Douglas production function, consumption and stochastic depreciation. The individual utility functional combines an own utility and a relative utility with respect to the population. The use of the relative utility reflects human psychology, leading to a natural pattern of mean field interaction. The fixed point equation of the mean field game is derived with the aid of some ordinary differential equations. Due to the relative utility interaction, our performance analysis depends on some ratio based approximation errormore » estimate.« less

Stochastic analysis of uncertain thermal parameters for random thermal regime of frozen soil around a single freezing pipe

NASA Astrophysics Data System (ADS)

Wang, Tao; Zhou, Guoqing; Wang, Jianzhou; Zhou, Lei

2018-03-01

The artificial ground freezing method (AGF) is widely used in civil and mining engineering, and the thermal regime of frozen soil around the freezing pipe affects the safety of design and construction. The thermal parameters can be truly random due to heterogeneity of the soil properties, which lead to the randomness of thermal regime of frozen soil around the freezing pipe. The purpose of this paper is to study the one-dimensional (1D) random thermal regime problem on the basis of a stochastic analysis model and the Monte Carlo (MC) method. Considering the uncertain thermal parameters of frozen soil as random variables, stochastic processes and random fields, the corresponding stochastic thermal regime of frozen soil around a single freezing pipe are obtained and analyzed. Taking the variability of each stochastic parameter into account individually, the influences of each stochastic thermal parameter on stochastic thermal regime are investigated. The results show that the mean temperatures of frozen soil around the single freezing pipe with three analogy method are the same while the standard deviations are different. The distributions of standard deviation have a great difference at different radial coordinate location and the larger standard deviations are mainly at the phase change area. The computed data with random variable method and stochastic process method have a great difference from the measured data while the computed data with random field method well agree with the measured data. Each uncertain thermal parameter has a different effect on the standard deviation of frozen soil temperature around the single freezing pipe. These results can provide a theoretical basis for the design and construction of AGF.

Plumbing the STEM Pipeline: Exploring Areas of Influence for Promoting STEM Education

NASA Astrophysics Data System (ADS)

Linger, Matthew

The U.S. has enjoyed several decades of science, technology, engineering and math (STEM) success but that is changing as U.S. students show less interest in advanced learning in STEM fields. Consequently, U.S. students are less scientifically and mathematically literate than past generations, a state that may negatively impact their chances of educational and career success. The reasons for the decline in STEM interest are unclear as many U.S. students still go on to earn STEM degrees and work in STEM fields. Often, these are students who showed a particular capacity for STEM subjects, identified through existing research as earning higher than average SAT scores, especially SAT-math, or high science and math achievement test scores. This study looked at these and other factors as a means to determine what impact they have on U.S. students' interest in pursuing a STEM line of study. The study aimed to determine in what way the U.S. educational system can positively influence high school students toward pursuing a STEM college education. The High School Longitudinal Study of 2009 (HSLS:09) was used as the data source. More than 21,000 students were part of the observations. Factor analysis was used to turn related variables into larger constructs. Constructs and original HSLS:09 variables were analyzed through logistic regression analysis with STATA software. Few high school level instructional and non-instructional interventions were found to have an impact on a student's career choice in 9 th grade of his or her choice of college major in 12th grade. On the contrary, student attitudinal variables were shown to be most influential.

Nimbus 7 earth radiation budget wide field of view climate data set improvement. I - The earth albedo from deconvolution of shortwave measurements

NASA Technical Reports Server (NTRS)

Hucek, Richard R.; Ardanuy, Philip E.; Kyle, H. Lee

1987-01-01

A deconvolution method for extracting the top of the atmosphere (TOA) mean, daily albedo field from a set of wide-FOV (WFOV) shortwave radiometer measurements is proposed. The method is based on constructing a synthetic measurement for each satellite observation. The albedo field is represented as a truncated series of spherical harmonic functions, and these linear equations are presented. Simulation studies were conducted to determine the sensitivity of the method. It is observed that a maximum of about 289 pieces of data can be extracted from a set of Nimbus 7 WFOV satellite measurements. The albedos derived using the deconvolution method are compared with albedos derived using the WFOV archival method; the developed albedo field achieved a 20 percent reduction in the global rms regional reflected flux density errors. The deconvolution method is applied to estimate the mean, daily average TOA albedo field for January 1983. A strong and extensive albedo maximum (0.42), which corresponds to the El Nino/Southern Oscillation event of 1982-1983, is detected over the south central Pacific Ocean.

Integrating Security into the Curriculum

DTIC Science & Technology

1998-12-01

predicate calculus, discrete math , and finite-state machine the- ory. In addition to applying standard mathematical foundations to constructing hardware and...models, specifi- cations, and the use of formal methods for verification and covert channel analysis. The means for analysis is based on discrete math , information

Dst and a map of average equivalent ring current: 1958-2007

NASA Astrophysics Data System (ADS)

Love, J. J.

2008-12-01

A new Dst index construction is made using the original hourly magnetic-observatory data collected over the years 1958-2007; stations: Hermanus South Africa, Kakioka Japan, Honolulu Hawaii, and San Juan Puerto Rico. The construction method we use is generally consistent with the algorithm defined by Sugiura (1964), and which forms the basis for the standard Kyoto Dst index. This involves corrections for observatory baseline shifts, subtraction of the main-field secular variation, and subtraction of specific harmonics that approximate the solar-quiet (Sq) variation. Fourier analysis of the observatory data reveals the nature of Sq: it consists primarily of periodic variation driven by the Earth's rotation, the Moon's orbit, the Earth's orbit, and, to some extent, the solar cycle. Cross coupling of the harmonics associated with each of the external periodic driving forces results in a seemingly complicated Sq time series that is sometimes considered to be relatively random and unpredictable, but which is, in fact, well described in terms of Fourier series. Working in the frequency domain, Sq can be filtered out, and, upon return to the time domain, the local disturbance time series (Dist) for each observatory can be recovered. After averaging the local disturbance time series from each observatory, the global magnetic disturbance time series Dst is obtained. Analysis of this new Dst index is compared with that produced by Kyoto, and various biases and differences are discussed. The combination of the Dist and Dst time series can be used to explore the local-time/universal-time symmetry of an equivalent ring current. Individual magnetic storms can have a complicated disturbance field that is asymmetrical in longitude, presumably due to partial ring currents. Using 50 years of data we map the average local-time magnetic disturbance, finding that it is very nearly proportional to Dst. To our surprise, the primary asymmetry in mean magnetic disturbance is not between midnight and noon, but rather between dawn and dusk, with greatest mean disturbance occurring at dusk. As a result, proposed corrections to Dst for magnetopause and tail currents might be reasonably reconsidered.

Preservice elementary teachers' use of a discursive model of meaning making in the co-construction of science understanding

NASA Astrophysics Data System (ADS)

Boyer, Elisebeth C.

This research investigates how three preservice elementary teachers were prepared to teach science using a Discursive Model of Meaning Making. The research is divided into two parts. The first consists of the nature of the participants’ learning experiences in a science methods course within a school-university Professional Development School partnership. This part of the investigation used Constant Comparative Analysis of field notes gathered through participant observation of the methods course. The analysis investigated how the methods instructors employed productive questioning, talk moves, and a coherent research based Teaching Science as Argument Framework. The second part of the study consisted of an investigation into how the participants applied what they experienced during the methods course in their initial science teaching experiences, as well as how the participants made sense of their initial science teaching. Data consisted of teaching videos of the participants during their initial science teaching experiences and self-analysis videos created by the participants. This part of the research used Discourse Analysis of the teaching and self-analysis videos. These inquiries provide insight into what aspects of the methods course were taken up by the participants and how they made sense of their practices. Findings are: 1) Throughout the methods course, instructors modeled how the Teaching Science as Argument Framework can be used to negotiate scientific understanding by employing a Discursive Model of Meaning Making. 2) During lesson plan conferences the Discursive Model was emphasized as participants planned classroom discussion and explored possible student responses enabling them to anticipate how they could attempt to increase student understanding. 3) Participants displayed three distinct patterns of adoption of the Teaching Science as Argument Framework (TSAF), involving different discursive practices. They were, • Detached Discursive Approach: Use of some discursive strategies without an apparent connection to the TSAF. • Connected Approach with a Focus on Student Thinking: Intentional use of the Discursive Model informed by aspects of the TSAF. • TSAF Approach: Priority is given to the TSAF supported by substantial application of the Discursive Model. 4) The evidence participants chose to highlight in their self-analysis videos is reflective of their patterns of adoption of the Teaching Science as Argument Framework and their differing discursive practices. Analysis led to the formation of the middle theory that when learning to teach science in the elementary school, teacher commitment to the discourse and practices of science is constructed through participation in a learning community where a discursive model of meaning making is the norm. Curricular and methodological implications, as well as implications for future research are presented.

A framework of analysis for field experiments with alternative materials in road construction.

PubMed

François, D; Jullien, A

2009-01-01

In France, a wide variety of alternative materials is produced or exists in the form of stockpiles built up over time. Such materials are distributed over various regions of the territory depending on local industrial development and urbanisation trends. The use of alternative materials at a national scale implies sharing local knowledge and experience. Building a national database on alternative materials for road construction is useful in gathering and sharing information. An analysis of feedback from onsite experiences (back analysis) is essential to improve knowledge on alternative material use in road construction. Back analysis of field studies has to be conducted in accordance with a single common framework. This could enable drawing comparisons between alternative materials and between road applications. A framework for the identification and classification of data used in back analyses is proposed. Since the road structure is an open system, this framework has been based on a stress-response approach at both the material and structural levels and includes a description of external factors applying during the road service life. The proposal has been shaped from a review of the essential characteristics of road materials and structures, as well as from the state of knowledge specific to alternative material characterisation.

Dynamic balance in turbulent reconnection

NASA Astrophysics Data System (ADS)

Yokoi, N.; Higashimori, K.; Hoshino, M.

2012-12-01

Dynamic balance between the enhancement and suppression of transports due to turbulence in magnetic reconnection is discussed analytically and numerically by considering the interaction of the large-scale field structures with the small-scale turbulence in a consistent manner. Turbulence is expected to play an important role in bridging small and large scales related to magnetic reconnection. The configurations of the mean-field structure are determined by turbulence through the effective transport. At the same time, statistical properties of turbulence are determined by the mean-field structure through the production mechanisms of turbulence. This suggests that turbulence and mean fields should be considered simultaneously in a self-consistent manner. Following the theoretical prediction on the interaction between the mean-fields and turbulence in magnetic reconnection presented by Yokoi and Hoshino (2011), a self-consistent model for the turbulent reconnection is constructed. In the model, the mean-field equations for compressible magnetohydrodynamics are treated with the turbulence effects incorporated through the turbulence correlation such as the Reynolds stress and turbulent electromotive force. Transport coefficients appearing in the expression for these correlations are not adjustable parameters but are determined through the transport equations of the turbulent statistical quantities such as the turbulent MHD energy, the turbulent cross helicity. One of the prominent features of this reconnection model lies in the point that turbulence is not implemented as a prescribed one, but the generation and sustainment of turbulence through the mean-field inhomogeneities are treated. The theoretical predictions are confirmed by the numerical simulation of the model equations. These predictions include the quadrupole cross helicity distribution around the reconnection region, enhancement of reconnection rate due to turbulence, localization of the reconnection region through the cross-helicity effect, etc. Some implications to the satellite observation of the magnetic reconnection will be also given. Reference: Yokoi, N. and Hoshino, M. (2011) Physics of Plasmas, 18, 111208.

Cosmic-Ray Propagation in Turbulent Spiral Magnetic Fields Associated with Young Stellar Objects

NASA Astrophysics Data System (ADS)

Fatuzzo, Marco; Adams, Fred C.

2018-04-01

External cosmic rays impinging upon circumstellar disks associated with young stellar objects provide an important source of ionization, and, as such, play an important role in disk evolution and planet formation. However, these incoming cosmic rays are affected by a variety of physical processes internal to stellar/disk systems, including modulation by turbulent magnetic fields. Globally, these fields naturally provide both a funneling effect, where cosmic rays from larger volumes are focused into the disk region, and a magnetic mirroring effect, where cosmic rays are repelled due to the increasing field strength. This paper considers cosmic-ray propagation in the presence of a turbulent spiral magnetic field, analogous to that produced by the solar wind. The interaction of this wind with the interstellar medium defines a transition radius, analogous to the heliopause, which provides the outer boundary to this problem. We construct a new coordinate system where one coordinate follows the spiral magnetic field lines and consider magnetic perturbations to the field in the perpendicular directions. The presence of magnetic turbulence replaces the mirroring points with a distribution of values and moves the mean location outward. Our results thus help quantify the degree to which cosmic-ray fluxes are reduced in circumstellar disks by the presence of magnetic field structures that are shaped by stellar winds. The new coordinate system constructed herein should also be useful in other astronomical applications.

Negative ion beam injection apparatus with magnetic shield and electron removal means

DOEpatents

Anderson, Oscar A.; Chan, Chun F.; Leung, Ka-Ngo

1994-01-01

A negative ion source is constructed to produce H.sup.- ions without using Cesium. A high percentage of secondary electrons that typically accompany the extracted H.sup.- are trapped and eliminated from the beam by permanent magnets in the initial stage of acceleration. Penetration of the magnetic field from the permanent magnets into the ion source is minimized. This reduces the destructive effect the magnetic field could have on negative ion production and extraction from the source. A beam expansion section in the extractor results in a strongly converged final beam.

Neutron Stars with Delta-Resonances in the Walecka and Zimanyi-Moszkowski Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fong, C. T.; Oliveira, J. C. T.; Rodrigues, H.

2010-11-12

In the present work we have obtained the equation of state of the highly asymmetric dense stellar matter focusing on the delta resonance formation. We extended the nonlinear Walecka (NLW) and Zimanyi-Moszkowski (ZM) models to accommodate in the context of the relativistic mean field approximation the Rarita-Schwinger field for the spin 3/2 resonances. With the constructed stellar matter equations of state we solve numerically the TOV equation (Tolman-Oppenheimer-Volkoff) in order to determine the internal structure of neutron stars, and discuss the obtained masses versus radii diagram.

Determination of the Alfvén Speed and Plasma-beta Using the Seismology of Sunspot Umbra

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cho, I.-H.; Moon, Y.-J.; Nakariakov, V. M.

For 478 centrally located sunspots observed in the optical continuum with Solar Dynamics Observatory /Helioseismic Magnetic Imager, we perform seismological diagnostics of the physical parameters of umbral photospheres. The new technique is based on the theory of slow magnetoacoustic waves in a non-isothermally stratified photosphere with a uniform vertical magnetic field. We construct a map of the weighted frequency of three-minute oscillations inside the umbra and use it for the estimation of the Alfvén speed, plasma-beta, and mass density within the umbra. We find the umbral mean Alfvén speed ranges between 10.5 and 7.5 km s{sup −1} and is negativelymore » correlated with magnetic field strength. The umbral mean plasma-beta is found to range approximately between 0.65 and 1.15 and does not vary significantly from pores to mature sunspots. The mean density ranges between (1–6) × 10{sup −4} kg m{sup −3} and shows a strong positive correlation with magnetic field strength.« less

Missing data methods for dealing with missing items in quality of life questionnaires. A comparison by simulation of personal mean score, full information maximum likelihood, multiple imputation, and hot deck techniques applied to the SF-36 in the French 2003 decennial health survey.

PubMed

Peyre, Hugo; Leplège, Alain; Coste, Joël

2011-03-01

Missing items are common in quality of life (QoL) questionnaires and present a challenge for research in this field. It remains unclear which of the various methods proposed to deal with missing data performs best in this context. We compared personal mean score, full information maximum likelihood, multiple imputation, and hot deck techniques using various realistic simulation scenarios of item missingness in QoL questionnaires constructed within the framework of classical test theory. Samples of 300 and 1,000 subjects were randomly drawn from the 2003 INSEE Decennial Health Survey (of 23,018 subjects representative of the French population and having completed the SF-36) and various patterns of missing data were generated according to three different item non-response rates (3, 6, and 9%) and three types of missing data (Little and Rubin's "missing completely at random," "missing at random," and "missing not at random"). The missing data methods were evaluated in terms of accuracy and precision for the analysis of one descriptive and one association parameter for three different scales of the SF-36. For all item non-response rates and types of missing data, multiple imputation and full information maximum likelihood appeared superior to the personal mean score and especially to hot deck in terms of accuracy and precision; however, the use of personal mean score was associated with insignificant bias (relative bias <2%) in all studied situations. Whereas multiple imputation and full information maximum likelihood are confirmed as reference methods, the personal mean score appears nonetheless appropriate for dealing with items missing from completed SF-36 questionnaires in most situations of routine use. These results can reasonably be extended to other questionnaires constructed according to classical test theory.

Dynamical mean-field theory on the real-frequency axis: p -d hybridization and atomic physics in SrMnO3

NASA Astrophysics Data System (ADS)

Bauernfeind, Daniel; Triebl, Robert; Zingl, Manuel; Aichhorn, Markus; Evertz, Hans Gerd

2018-03-01

We investigate the electronic structure of SrMnO3 with density functional theory plus dynamical mean-field theory (DMFT). Within this scheme the selection of the correlated subspace and the construction of the corresponding Wannier functions is a crucial step. Due to the crystal-field splitting of the Mn-3 d orbitals and their separation from the O -2 p bands, SrMnO3 is a material where on first sight a three-band d -only model should be sufficient. However, in the present work we demonstrate that the resulting spectrum is considerably influenced by the number of correlated orbitals and the number of bands included in the Wannier function construction. For example, in a d -d p model we observe a splitting of the t2 g lower Hubbard band into a more complex spectral structure, not observable in d -only models. To illustrate these high-frequency differences we employ the recently developed fork tensor product state (FTPS) impurity solver, as it provides the necessary spectral resolution on the real-frequency axis. We find that the spectral structure of a five-band d -d p model is in good agreement with PES and XAS experiments. Our results demonstrate that the FTPS solver is capable of performing full five-band DMFT calculations directly on the real-frequency axis.

Models for the dynamics of dust-like matter in the self-gravity field: The method of hydrodynamic substitutions

NASA Astrophysics Data System (ADS)

Zhuravlev, V. M.

2017-09-01

Models for the dynamics of a dust-like medium in the self-gravity field are investigated. Solutions of the corresponding problems are constructed by the method of hydrodynamic substitutions generalizing the Cole-Hopf substitutions. The method is extended to multidimensional ideal and viscous fluid flows with cylindrical and spherical symmetries for which exact solutions are constructed. Solutions for the dynamics of self-gravitating dust with arbitrary initial distributions of both fluid density and velocity are constructed using special coordinate transformations. In particular, the problem of cosmological expansion is considered in terms of Newton's gravity theory. Models of a one-dimensional viscous dust fluid flow and some problems of gas hydrodynamics are considered. Examples of exact solutions and their brief analysis are provided.

Confirming and denying in co-construction processes: a case study of an adult with cerebral palsy and two familiar partners.

PubMed

Hörmeyer, Ina; Renner, Gregor

2013-09-01

For individuals with complex communication needs, one of the most frequent communicative strategies is the co-construction of meaning with familiar partners. This preliminary single-case study gives insight into a special sequential pattern of co-construction processes - the search sequence - particularly in relation to the processes of confirming and denying meanings proposed by familiar interaction partners. Five different conversations between an adult with cerebral palsy and complex communication needs and two familiar co-participants were videotaped and analyzed using the methodology of conversation analysis (CA). The study revealed that confirmations and denials are not simply two alternative actions, but that several possibilities to realize confirmations and denials exist that differ in their frequency and that have different consequences for the sequential context. This study of confirmations and denials demonstrates that co-construction processes are more complex than have previously been documented.

Comparison Of The Global Analytic Models Of The Main Geomagnetic Field With The Stratospheric Balloon Magnetic Data 335

NASA Astrophysics Data System (ADS)

Tsvetkov, Yu.; Filippov, S.; Frunze, A.

2013-12-01

Three global analytical models of a main geomagnetic field constructed by satellite data are used: model IGRF, Daily Mean Spherical Harmonic Models (DMSHM), and model EMM/2010, and also scalar data of geomagnetic field and its gradients, received in stratospheric balloon gradient magnetic surveys at altitudes of ~30 km. At these altitudes the regional magnetic field is formed from all sources of the Earth's crust. It enables to receive along lengthy routes of surveys the fullest data on regional and longwave-lenght magnetic anomalies. Model DMSHM is used at extracting of magnetic anomalies for elimination of a secular variation up to significant value 0,2 nT. The model can be constructed within the limits of ± 1 months from the moment stratospheric balloon surveys with beneficial day terms with magnetic activity up to Kp <20, that leads to an error of representation of main MFE equal ±5 нТл. It is possible at presence acting for the period of stratospheric balloon magnetic survey of the satellite, for example, Swarm. On stratospheric balloon data it is shown, that model EMM/2010 unsatisfactorily displays MFE at altitude of 30 km. Hence, the qualitative model of the constant (main and anomaly) magnetic field cannot be constructed only with use of satellite and ground data. The improved model constant MFE, constructed according to satellite and stratospheric balloon magnetic surveys, developed up to a degree and the order m=n=720, will have a reliable data about regional crust magnetic field, hence, and about deep magnetic structure of the Earth's crust. The use gradient magnetic surveys aboard stratospheric balloons allows to find the places alternating approximately through 3000 km in which there are no magnetic anomalies. In these places probably to supervise satellite magnetic models for a range of altitude of 20-40 km, timed to stratospheric balloon magnetic surveys.

Neural Network Machine Learning and Dimension Reduction for Data Visualization

NASA Technical Reports Server (NTRS)

Liles, Charles A.

2014-01-01

Neural network machine learning in computer science is a continuously developing field of study. Although neural network models have been developed which can accurately predict a numeric value or nominal classification, a general purpose method for constructing neural network architecture has yet to be developed. Computer scientists are often forced to rely on a trial-and-error process of developing and improving accurate neural network models. In many cases, models are constructed from a large number of input parameters. Understanding which input parameters have the greatest impact on the prediction of the model is often difficult to surmise, especially when the number of input variables is very high. This challenge is often labeled the "curse of dimensionality" in scientific fields. However, techniques exist for reducing the dimensionality of problems to just two dimensions. Once a problem's dimensions have been mapped to two dimensions, it can be easily plotted and understood by humans. The ability to visualize a multi-dimensional dataset can provide a means of identifying which input variables have the highest effect on determining a nominal or numeric output. Identifying these variables can provide a better means of training neural network models; models can be more easily and quickly trained using only input variables which appear to affect the outcome variable. The purpose of this project is to explore varying means of training neural networks and to utilize dimensional reduction for visualizing and understanding complex datasets.

Multidimensional Aspects of Literacy Research, Theory, and Practice. Forty-Third Yearbook of the National Reading Conference.

ERIC Educational Resources Information Center

Kinzer, Charles K., Ed.; Leu, Donald J., Ed.

The 55 conference papers, the annual review of research, and the student-award-winning paper in this yearbook cover such diverse topics in the field of reading as assessment, content-area reading, early literacy, teacher education, teacher behavior, and construction of meaning through writing. The yearbook opens with the presidential address to…

A statistical motion model based on biomechanical simulations for data fusion during image-guided prostate interventions.

PubMed

Hu, Yipeng; Morgan, Dominic; Ahmed, Hashim Uddin; Pendsé, Doug; Sahu, Mahua; Allen, Clare; Emberton, Mark; Hawkes, David; Barratt, Dean

2008-01-01

A method is described for generating a patient-specific, statistical motion model (SMM) of the prostate gland. Finite element analysis (FEA) is used to simulate the motion of the gland using an ultrasound-based 3D FE model over a range of plausible boundary conditions and soft-tissue properties. By applying principal component analysis to the displacements of the FE mesh node points inside the gland, the simulated deformations are then used as training data to construct the SMM. The SMM is used to both predict the displacement field over the whole gland and constrain a deformable surface registration algorithm, given only a small number of target points on the surface of the deformed gland. Using 3D transrectal ultrasound images of the prostates of five patients, acquired before and after imposing a physical deformation, to evaluate the accuracy of predicted landmark displacements, the mean target registration error was found to be less than 1.9 mm.

Constructions of Mathematicians in Popular Culture and Learners' Narratives: A Study of Mathematical and Non-Mathematical Subjectivities

ERIC Educational Resources Information Center

Moreau, Marie-Pierre; Mendick, Heather; Epstein, Debbie

2010-01-01

In this paper, based on a project funded by the UK Economic and Social Research Council considering how people position themselves in relation to popular representations of mathematics and mathematicians, we explore constructions of mathematicians in popular culture and the ways learners make meanings from these. Drawing on an analysis of popular…

The Construction of Academic Identity in the Changes of Finnish Higher Education

ERIC Educational Resources Information Center

Ylijoki, Oili-Helena; Ursin, Jani

2013-01-01

This article sets out to explore how academics make sense of the current transformations of higher education and what kinds of academic identities are thereby constructed. Based on a narrative analysis of 42 interviews with Finnish academics, nine narratives are discerned, each providing a different answer as to what it means to be an academic in…

Construction and application research of Three-dimensional digital power grid in Southwest China

NASA Astrophysics Data System (ADS)

Zhou, Yang; Zhou, Hong; You, Chuan; Jiang, Li; Xin, Weidong

2018-01-01

With the rapid development of Three-dimensional (3D) digital design technology in the field of power grid construction, the data foundation and technical means of 3D digital power grid construction approaches perfection. 3D digital power grid has gradually developed into an important part of power grid construction and management. In view of the complicated geological conditions in Southwest China and the difficulty in power grid construction and management, this paper is based on the data assets of Southwest power grid, and it aims at establishing a 3D digital power grid in Southwest China to provide effective support for power grid construction and operation management. This paper discusses the data architecture, technical architecture and system design and implementation process of the 3D digital power grid construction through teasing the key technology of 3D digital power grid. The application of power grid data assets management, transmission line corridor planning, geological hazards risk assessment, environmental impact assessment in 3D digital power grid are also discussed and analysed.

DOUBLE DYNAMO SIGNATURES IN A GLOBAL MHD SIMULATION AND MEAN-FIELD DYNAMOS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beaudoin, Patrice; Simard, Corinne; Cossette, Jean-François

The 11 year solar activity cycle is the most prominent periodic manifestation of the magnetohydrodynamical (MHD) large-scale dynamo operating in the solar interior, yet longer and shorter (quasi-) periodicities are also present. The so-called “quasi-biennial” signal appearing in many proxies of solar activity has been gaining increasing attention since its detection in p -mode frequency shifts, which suggests a subphotospheric origin. A number of candidate mechanisms have been proposed, including beating between co-existing global dynamo modes, dual dynamos operating in spatially separated regions of the solar interior, and Rossby waves driving short-period oscillations in the large-scale solar magnetic field producedmore » by the 11 year activity cycle. In this article, we analyze a global MHD simulation of solar convection producing regular large-scale magnetic cycles, and detect and characterize shorter periodicities developing therein. By constructing kinematic mean-field α {sup 2}Ω dynamo models incorporating the turbulent electromotive force (emf) extracted from that same simulation, we find that dual-dynamo behavior materializes in fairly wide regions of the model’s parameters space. This suggests that the origin of the similar behavior detected in the MHD simulation lies with the joint complexity of the turbulent emf and differential rotation profile, rather that with dynamical interactions such as those mediated by Rossby waves. Analysis of the simulation also reveals that the dual dynamo operating therein leaves a double-period signature in the temperature field, consistent with a dual-period helioseismic signature. Order-of-magnitude estimates for the magnitude of the expected frequency shifts are commensurate with helioseismic measurements. Taken together, our results support the hypothesis that the solar quasi-biennial oscillations are associated with a secondary dynamo process operating in the outer reaches of the solar convection zone.« less

Analysis of factors influencing safety management for metro construction in China.

PubMed

Yu, Q Z; Ding, L Y; Zhou, C; Luo, H B

2014-07-01

With the rapid development of urbanization in China, the number and size of metro construction projects are increasing quickly. At the same time, and increasing number of accidents in metro construction make it a disturbing focus of social attention. In order to improve safety management in metro construction, an investigation of the participants' perspectives on safety factors in China metro construction has been conducted to identify the key safety factors, and their ranking consistency among the main participants, including clients, consultants, designers, contractors and supervisors. The result of factor analysis indicates that there are five key factors which influence the safety of metro construction including safety attitude, construction site safety, government supervision, market restrictions and task unpredictability. In addition, ANOVA and Spearman rank correlation coefficients were performed to test the consistency of the means rating and the ranking of safety factors. The results indicated that the main participants have significant disagreement about the importance of safety factors on more than half of the items. Suggestions and recommendations on practical countermeasures to improve metro construction safety management in China are proposed. Copyright © 2013 Elsevier Ltd. All rights reserved.

An effective approach to quantitative analysis of ternary amino acids in foxtail millet substrate based on terahertz spectroscopy.

PubMed

Lu, Shao Hua; Li, Bao Qiong; Zhai, Hong Lin; Zhang, Xin; Zhang, Zhuo Yong

2018-04-25

Terahertz time-domain spectroscopy has been applied to many fields, however, it still encounters drawbacks in multicomponent mixtures analysis due to serious spectral overlapping. Here, an effective approach to quantitative analysis was proposed, and applied on the determination of the ternary amino acids in foxtail millet substrate. Utilizing three parameters derived from the THz-TDS, the images were constructed and the Tchebichef image moments were used to extract the information of target components. Then the quantitative models were obtained by stepwise regression. The correlation coefficients of leave-one-out cross-validation (R loo-cv 2 ) were more than 0.9595. As for external test set, the predictive correlation coefficients (R p 2 ) were more than 0.8026 and the root mean square error of prediction (RMSE p ) were less than 1.2601. Compared with the traditional methods (PLS and N-PLS methods), our approach is more accurate, robust and reliable, and can be a potential excellent approach to quantify multicomponent with THz-TDS spectroscopy. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Construction and application of bioinformatic analysis platform for aquatic pathogen based on the MilkyWay-2 supercomputer].

PubMed

Fang, Xiang; Li, Ning-qiu; Fu, Xiao-zhe; Li, Kai-bin; Lin, Qiang; Liu, Li-hui; Shi, Cun-bin; Wu, Shu-qin

2015-07-01

As a key component of life science, bioinformatics has been widely applied in genomics, transcriptomics, and proteomics. However, the requirement of high-performance computers rather than common personal computers for constructing a bioinformatics platform significantly limited the application of bioinformatics in aquatic science. In this study, we constructed a bioinformatic analysis platform for aquatic pathogen based on the MilkyWay-2 supercomputer. The platform consisted of three functional modules, including genomic and transcriptomic sequencing data analysis, protein structure prediction, and molecular dynamics simulations. To validate the practicability of the platform, we performed bioinformatic analysis on aquatic pathogenic organisms. For example, genes of Flavobacterium johnsoniae M168 were identified and annotated via Blast searches, GO and InterPro annotations. Protein structural models for five small segments of grass carp reovirus HZ-08 were constructed by homology modeling. Molecular dynamics simulations were performed on out membrane protein A of Aeromonas hydrophila, and the changes of system temperature, total energy, root mean square deviation and conformation of the loops during equilibration were also observed. These results showed that the bioinformatic analysis platform for aquatic pathogen has been successfully built on the MilkyWay-2 supercomputer. This study will provide insights into the construction of bioinformatic analysis platform for other subjects.

Development of the mathematical model for design and verification of acoustic modal analysis methods

NASA Astrophysics Data System (ADS)

Siner, Alexander; Startseva, Maria

2016-10-01

To reduce the turbofan noise it is necessary to develop methods for the analysis of the sound field generated by the blade machinery called modal analysis. Because modal analysis methods are very difficult and their testing on the full scale measurements are very expensive and tedious it is necessary to construct some mathematical models allowing to test modal analysis algorithms fast and cheap. At this work the model allowing to set single modes at the channel and to analyze generated sound field is presented. Modal analysis of the sound generated by the ring array of point sound sources is made. Comparison of experimental and numerical modal analysis results is presented at this work.

Expanding the Notion of Historical Text through Historic Building Analysis

ERIC Educational Resources Information Center

Baron, Christine; Dobbs, Christina

2015-01-01

Among the disciplinary skills necessary for understanding in the social studies classroom is the ability to determine context and build meaning from past events. Historical buildings are an important component of historical study, and they serve as a type of nontraditional text that students can decode and use to construct meaning about multiple…

Constructivism and Education: Education as an Interpretative Transformational Process

ERIC Educational Resources Information Center

Sutinen, Ari

2008-01-01

This paper provides an analysis of the ideas of John Dewey and George Herbert Mead with regards the relationship between experience, meaning, language and thinking. It discusses how experience, meaning, language and thinking are based on the creative and constructive actions of individuals. Unlike what is the case in so-called radical…

Transnational migration of Mexican scientists: A circuit between Mexico and the EEUU

NASA Astrophysics Data System (ADS)

Tinoco Herrera, Mario Luis

The experience and meaning of migration for a group of Mexican scientists participating in the construction of a migratory circuit between Mexico and US within the field of agricultural sciences is the object of this study. I define this migratory circuit of scientists as a social, historical and cultural process, and draw from transnational migration theories to analyze it. From this perspective, I view the migratory circuit of Mexican scientists to be a field of social relationships extended across Mexico and the US. In studying the migratory experience and its significance, I draw upon the methods of historical reconstruction of the circuit of scientists between Mexico and the US, participatory observation, informal narratives, testimonies and their analysis. This study focuses on three crucial moments of their migratory experience: (1) the moment prior to their trip to the US; (2) their academic training at a research center in the US; and (3) their return to a research center in Mexico. At the same time, this study highlights three key factors that determine and ascribe different meanings to the experiences of this migratory circuit: gender, academic trajectory, and the belonging to a migratory circuit. The findings from this study have shown that the experiences of migration and their multiple meanings are complex, heterogeneous and paradoxical. The complexity lies in the challenges of academic responsibilities and their near total integration and transformation of the participants' social life, as well as family life. These migratory experiences are further differentiated and problematic because of the various perceptions and sense of value that are mediated by gender, academic trajectory, and belonging to a circuit of migration; and, they are paradoxical because even though the experiences, perceptions and meanings are different and, at times, challenging, every single participant has described their experience as positive.

Sampling Scattered Data Onto Rectangular Grids for Volume Visualization

DTIC Science & Technology

1989-12-01

30 4.4 Building A Rectangular Grid ..... ................ 30 4.5 Sampling Methds ...... ...................... 34 4.6...dimensional data have been developed recently. In computational fluid flow analysis, methods for constructing three dimen- sional numerical grids are...structure of rectangular grids. Because finite element analysis is useful in fields other than fluid flow analysis and the numerical grid has promising

Reserve growth in oil fields of the North Sea

USGS Publications Warehouse

Klett, T.R.; Gautier, D.L.

2005-01-01

The assessment of petroleum resources of the North Sea, as well as other areas of the world, requires a viable means to forecast the amount of growth of reserve estimates (reserve growth) for discovered fields and to predict the potential fully developed sizes of undiscovered fields. This study investigates the utility of North Sea oil field data to construct reserve-growth models. Oil fields of the North Sea provide an excellent dataset in which to examine the mechanisms, characteristics, rates and quantities of reserve growth because of the high level of capital investments, implementation of sophisticated technologies and careful data collection. Additionally, these field data are well reported and available publicly. Increases in successive annual estimat es of recoverable crude oil volumes indicate that oil fields in the North Sea, collectively and in each country, experience reserve growth. Specific patterns of reserve growth are observed among countries and primary producing reservoir-rock types. Since 1985, Norwegian oil fields had the greatest volume increase; Danish oil fields increased by the greatest percentage relative to 1985 estimates; and British oil fields experienced an increase in recoverable oil estimates for the first ten years since 1985, followed by a slight reduction. Fields producing primarily from clastic reservoirs account for the majority of the estimated recoverable oil and, therefore, these fields had the largest volumetric increase. Fields producing primarily from chalk (limestone) reservoirs increased by a greater percentage relative to 1985 estimates than did fields producing primarily from clastic reservoirs. Additionally, the largest oil fields had the greatest volumetric increases. Although different reserve-growth patterns are observed among oil fields located in different countries, the small number of fields in Denmark precludes construction of reserve-growth models for that country. However, differences in reserve-growth patterns among oil fields that produce from primarily clastic and primarily chalk reservoirs, in addition to a greater number of fields in each of the two categories, allow separate reserve-growth models to be constructed based on reservoir-rock type. Reserve-growth models referenced to the date of discovery and to the date of first production may be constructed from North Sea field data. Years since discovery or years since first production are used as surrogates for, or measures of, field-development effort that is applied to promote reserve growth. Better estimates of recoverable oil are made as fields are developed. Because much of the field development occurs some time later than the field discovery date, reserve-growth models referenced to the date of first production may provide a more appropriate measure of development than does date of discovery. ?? 2005 EAGE/Geological Society of London.

LED intense headband light source for fingerprint analysis

DOEpatents

Villa-Aleman, Eliel

2005-03-08

A portable, lightweight and high-intensity light source for detecting and analyzing fingerprints during field investigation. On-site field analysis requires long hours of mobile analysis. In one embodiment, the present invention comprises a plurality of light emitting diodes; a power source; and a personal attachment means; wherein the light emitting diodes are powered by the power source, and wherein the power source and the light emitting diodes are attached to the personal attachment means to produce a personal light source for on-site analysis of latent fingerprints. The present invention is available for other applications as well.

Validation of the Functional Assessment of Chronic Illness Therapy-Spiritual Well-being (FACIT-Sp12) on French Old People.

PubMed

Agli, Océane; Bailly, Nathalie; Ferrand, Claude

2017-04-01

The study aimed to develop a French version of the Functional Assessment of Chronic Illness Therapy-Spiritual Well-being short version (FACIT-Sp12), in order to provide a self-reported measure for French people in the field of gerontology. The study involving 63 nursing home residents was conducted to evaluate the construct validity, reliability, and convergence validity of the FACIT-Sp12. A confirmatory factor analysis corroborated a three-factor model (Meaning, Peace and Faith) with modifications for two items, also valid among people with cognitive impairment. Subscales showed good internal consistency and are correlated with quality of life and depression. In conclusion, the validated French version is an suitable instrument to study the maintenance and promotion of quality of life in the elderly.

An investigation of the distribution of eruptive products on the shield volcanoes of the western Galapagos Islands using remotely sensed data

NASA Technical Reports Server (NTRS)

Munro, Duncan C.; Rowland, Scott K.; Mouginis-Mark, Peter J.; Wilson, Lionel; Oviedo-Perez, Victor-Hugo

1991-01-01

Recent volcanic activity in the Galapagos Islands is concentrated on the two westernmost islands, Isla Isabela and Isla Fernandina. Difficult access has thus far prevented comprehensive geological field studies, so we examine the potential of remotely sensed data as a means of studying volcanic processes in the region. Volcan Wolf is used as an example of the analysis of SPOT HRV-1 data undertaken for each volcano. Landsat TM data are analyzed in an attempt to construct a relative age sequence for the recent eruptive activity on Isla Fernandina. No systematic variation in the surface reflectance of lava flows as a function of age could be detected with these data. Thus it was not possible to complete a study of the temporal distribution of volcanic activity.

Magnetic Propulsion of Microswimmers with DNA-Based Flagellar Bundles.

PubMed

Maier, Alexander M; Weig, Cornelius; Oswald, Peter; Frey, Erwin; Fischer, Peer; Liedl, Tim

2016-02-10

We show that DNA-based self-assembly can serve as a general and flexible tool to construct artificial flagella of several micrometers in length and only tens of nanometers in diameter. By attaching the DNA flagella to biocompatible magnetic microparticles, we provide a proof of concept demonstration of hybrid structures that, when rotated in an external magnetic field, propel by means of a flagellar bundle, similar to self-propelling peritrichous bacteria. Our theoretical analysis predicts that flagellar bundles that possess a length-dependent bending stiffness should exhibit a superior swimming speed compared to swimmers with a single appendage. The DNA self-assembly method permits the realization of these improved flagellar bundles in good agreement with our quantitative model. DNA flagella with well-controlled shape could fundamentally increase the functionality of fully biocompatible nanorobots and extend the scope and complexity of active materials.

Qualitative analysis of decision making by speech-language pathologists in the design of aided visual displays.

PubMed

McFadd, Emily; Wilkinson, Krista

2010-06-01

For children with complex communication needs, augmentative and alternative communication (AAC) devices offer a functional way to communicate thoughts and feelings. Despite many significant advances in the field, effective and efficient aided communication can remain a challenge for some clients and their partners. One critical element of aided AAC intervention is systematic attention to the design of the communication display itself. A well-designed display will foster communication outcomes; a poorly designed one might have the opposite effect. Surprisingly, to our knowledge there are no studies of the strategies that clinicians actually employ when putting together a display. In this research note, we examine, on a case-by-case basis, the strategies six clinicians used when constructing display pages, as a means of highlighting potential areas that might warrant systematic research on display design.

Projection operators for the Rossby and Poincare waves in a beta-plane approximation

NASA Astrophysics Data System (ADS)

Lebedkina, Anastasia; Ivan, Karpov; Sergej, Leble

2013-04-01

Study of the wave structure variations of atmospheric parameters is a due to a solving of number practical problems associated with the weather and the state of the environment requires knowledge of the spectral characteristics of atmospheric waves. Modern methods, for identification of wave disturbances in the atmosphere, based on the harmonic analysis of observations. The success of these application is determined by the presence of sets of experimental data obtained in the long-term (over the period of the wave) of the atmosphere on a large number of independent observation stations. Currently, the system of observation in the atmosphere, both terrestrial and satellite, unevenly covers the surface of the Earth and, despite the length of observation, doesn't solve the problem of identification of waves. Thus, the problem of identification wave disturbances conflicts fundamental difficulties, and solution needs in a new methods for the analysis of observations. The work complete a procedure to construct a projection operators for large-scale waves in the atmosphere. Advantage of this method is the ability to identify type of wave and its characteristics only on the base of a time series of observations. It means that the problem of waves identification can be solved on the basis of only one station observations. In the method assumed that the observed spatial and temporal structure of the atmosphere is determined by the superposition of different type waves. For each type of waves involved in this superposition, dispersion and polarization relations (between the components of the wave vector of the field) expect as known. Based on these assumptions, we can construct projection operators on the initial superposition state on the linear basis of vectors corresponding to the known type of atmospheric waves. The action of the design on the superposition state, which, in fact, is the result of observations, determine the amplitude and phase of the waves of a known type. The idea to use the polarization relations for the classification of waves originated in radio physics in the works of A. A. Novikov. In the theory of the electromagnetic field polarization relations is traditionally included in the analysis of wave phenomena. In the theory of acoustic-gravity waves, projection operators were introduced in a works of S. B. Leble. The object of study is a four-dimentional vector (components of the velocity, pressure and temperature). Based on these assumptions, we can construct the projection operators for superposition state on the linear basis, corresponding to the well-known type of waves. In this paper we consider procedure for construction of a projection operators for planetary Rossby and Poincare waves in the Earth's atmosphere in the approximation of the "beta-plane". In a result of work we constructed projection operators in this approximation for Poincare and Rossby waves. The tests for operators shown, that separation of the contribution of corresponding waves from source of the wave field is possible. Estimation accuracy of the operators and results of applying operators to the data TEC presented.

Stability of holographic superconductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kanno, Sugumi; Soda, Jiro

We study the dynamical stability of holographic superconductors. We first classify perturbations around black hole background solutions into vector and scalar sectors by means of a 2-dimensional rotational symmetry. We prove the stability of the vector sector by explicitly constructing the positive definite Hamiltonian. To reveal a mechanism for the stabilization of a superconducting phase, we construct a quadratic action for the scalar sector. From the action, we see the stability of black holes near a critical point is determined by the equation of motion for a charged scalar field. We show the effective mass of the charged scalar fieldmore » in hairy black holes is always above the Breitenlohner-Freedman bound near the critical point due to the backreaction of a gauge field. It implies the stability of the superconducting phase. We also argue that the stability continues away from the critical point.« less

Normalization in Lie algebras via mould calculus and applications

NASA Astrophysics Data System (ADS)

Paul, Thierry; Sauzin, David

2017-11-01

We establish Écalle's mould calculus in an abstract Lie-theoretic setting and use it to solve a normalization problem, which covers several formal normal form problems in the theory of dynamical systems. The mould formalism allows us to reduce the Lie-theoretic problem to a mould equation, the solutions of which are remarkably explicit and can be fully described by means of a gauge transformation group. The dynamical applications include the construction of Poincaré-Dulac formal normal forms for a vector field around an equilibrium point, a formal infinite-order multiphase averaging procedure for vector fields with fast angular variables (Hamiltonian or not), or the construction of Birkhoff normal forms both in classical and quantum situations. As a by-product we obtain, in the case of harmonic oscillators, the convergence of the quantum Birkhoff form to the classical one, without any Diophantine hypothesis on the frequencies of the unperturbed Hamiltonians.

Steady-state groundwater recharge in trapezoidal-shaped aquifers: A semi-analytical approach based on variational calculus

NASA Astrophysics Data System (ADS)

Mahdavi, Ali; Seyyedian, Hamid

2014-05-01

This study presents a semi-analytical solution for steady groundwater flow in trapezoidal-shaped aquifers in response to an areal diffusive recharge. The aquifer is homogeneous, anisotropic and interacts with four surrounding streams of constant-head. Flow field in this laterally bounded aquifer-system is efficiently constructed by means of variational calculus. This is accomplished by minimizing a properly defined penalty function for the associated boundary value problem. Simple yet demonstrative scenarios are defined to investigate anisotropy effects on the water table variation. Qualitative examination of the resulting equipotential contour maps and velocity vector field illustrates the validity of the method, especially in the vicinity of boundary lines. Extension to the case of triangular-shaped aquifer with or without an impervious boundary line is also demonstrated through a hypothetical example problem. The present solution benefits from an extremely simple mathematical expression and exhibits strictly close agreement with the numerical results obtained from Modflow. Overall, the solution may be used to conduct sensitivity analysis on various hydrogeological parameters that affect water table variation in aquifers defined in trapezoidal or triangular-shaped domains.

Beyond the first "click:" Women graduate students in computer science

NASA Astrophysics Data System (ADS)

Sader, Jennifer L.

This dissertation explored the ways that constructions of gender shaped the choices and expectations of women doctoral students in computer science. Women who do graduate work in computer science still operate in an environment where they are in the minority. How much of women's underrepresentation in computer science fields results from a problem of imagining women as computer scientists? As long as women in these fields are seen as exceptions, they are exceptions that prove the "rule" that computing is a man's domain. The following questions were the focus of this inquiry: What are the career aspirations of women doctoral students in computer science? How do they feel about their chances to succeed in their chosen career and field? How do women doctoral students in computer science construct womanhood? What are their constructions of what it means to be a computer scientist? In what ways, if any, do they believe their gender has affected their experience in their graduate programs? The goal was to examine how constructions of computer science and of gender---including participants' own understanding of what it meant to be a woman, as well as the messages they received from their environment---contributed to their success as graduate students in a field where women are still greatly outnumbered by men. Ten women from four different institutions of higher education were recruited to participate in this study. These women varied in demographic characteristics like age, race, and ethnicity. Still, there were many common threads in their experiences. For example, their construction of womanhood did not limit their career prospects to traditionally female jobs. They had grown up with the expectation that they would be able to succeed in whatever field they chose. Most also had very positive constructions of programming as something that was "fun," rewarding, and intellectually stimulating. Their biggest obstacles were feelings of isolation and a resulting loss of confidence. Implications for future research are provided. There are also several implications for practice, especially the recommendation that graduate schools provide more support for all of their students. The experiences of these women also suggest ways to more effectively recruit women students to computer science. The importance of women faculty in these students' success also suggests that schools trying to counteract gender imbalances should actively recruit women faculty to teach in fields where women are underrepresented. These faculty serve as important role models and mentors to women students in their field.

Tissue Equivalents Based on Cell-Seeded Biodegradable Microfluidic Constructs

PubMed Central

Borenstein, Jeffrey T.; Megley, Katie; Wall, Kimberly; Pritchard, Eleanor M.; Truong, David; Kaplan, David L.; Tao, Sarah L.; Herman, Ira M.

2010-01-01

One of the principal challenges in the field of tissue engineering and regenerative medicine is the formation of functional microvascular networks capable of sustaining tissue constructs. Complex tissues and vital organs require a means to support oxygen and nutrient transport during the development of constructs both prior to and after host integration, and current approaches have not demonstrated robust solutions to this challenge. Here, we present a technology platform encompassing the design, construction, cell seeding and functional evaluation of tissue equivalents for wound healing and other clinical applications. These tissue equivalents are comprised of biodegradable microfluidic scaffolds lined with microvascular cells and designed to replicate microenvironmental cues necessary to generate and sustain cell populations to replace dermal and/or epidermal tissues lost due to trauma or disease. Initial results demonstrate that these biodegradable microfluidic devices promote cell adherence and support basic cell functions. These systems represent a promising pathway towards highly integrated three-dimensional engineered tissue constructs for a wide range of clinical applications.

Optimization of Regional Geodynamic Models for Mantle Dynamics

NASA Astrophysics Data System (ADS)

Knepley, M.; Isaac, T.; Jadamec, M. A.

2016-12-01

The SubductionGenerator program is used to construct high resolution, 3D regional thermal structures for mantle convection simulations using a variety of data sources, including sea floor ages and geographically referenced 3D slab locations based on seismic observations. The initial bulk temperature field is constructed using a half-space cooling model or plate cooling model, and related smoothing functions based on a diffusion length-scale analysis. In this work, we seek to improve the 3D thermal model and test different model geometries and dynamically driven flow fields using constraints from observed seismic velocities and plate motions. Through a formal adjoint analysis, we construct the primal-dual version of the multi-objective PDE-constrained optimization problem for the plate motions and seismic misfit. We have efficient, scalable preconditioners for both the forward and adjoint problems based upon a block preconditioning strategy, and a simple gradient update is used to improve the control residual. The full optimal control problem is formulated on a nested hierarchy of grids, allowing a nonlinear multigrid method to accelerate the solution.

Developing evaluation instrument based on CIPP models on the implementation of portfolio assessment

NASA Astrophysics Data System (ADS)

Kurnia, Feni; Rosana, Dadan; Supahar

2017-08-01

This study aimed to develop an evaluation instrument constructed by CIPP model on the implementation of portfolio assessment in science learning. This study used research and development (R & D) method; adapting 4-D by the development of non-test instrument, and the evaluation instrument constructed by CIPP model. CIPP is the abbreviation of Context, Input, Process, and Product. The techniques of data collection were interviews, questionnaires, and observations. Data collection instruments were: 1) the interview guidelines for the analysis of the problems and the needs, 2) questionnaire to see level of accomplishment of portfolio assessment instrument, and 3) observation sheets for teacher and student to dig up responses to the portfolio assessment instrument. The data obtained was quantitative data obtained from several validators. The validators consist of two lecturers as the evaluation experts, two practitioners (science teachers), and three colleagues. This paper shows the results of content validity obtained from the validators and the analysis result of the data obtained by using Aikens' V formula. The results of this study shows that the evaluation instrument based on CIPP models is proper to evaluate the implementation of portfolio assessment instruments. Based on the experts' judgments, practitioners, and colleagues, the Aikens' V coefficient was between 0.86-1,00 which means that it is valid and can be used in the limited trial and operational field trial.

Coupled structural, thermal, phase-change and electromagnetic analysis for superconductors, volume 2

NASA Technical Reports Server (NTRS)

Felippa, Carlos A.; Farhat, Charbel; Park, K. C.; Militello, Carmelo; Schuler, James J.

1993-01-01

Two families of parametrized mixed variational principles for linear electromagnetodynamics are constructed. The first family is applicable when the current density distribution is known a priori. Its six independent fields are magnetic intensity and flux density, magnetic potential, electric intensity and flux density and electric potential. Through appropriate specialization of parameters the first principle reduces to more conventional principles proposed in the literature. The second family is appropriate when the current density distribution and a conjugate Lagrange multiplier field are adjoined, giving a total of eight independently varied fields. In this case it is shown that a conventional variational principle exists only in the time-independent (static) case. Several static functionals with reduced number of varied fields are presented. The application of one of these principles to construct finite elements with current prediction capabilities is illustrated with a numerical example.

From spinning conformal blocks to matrix Calogero-Sutherland models

NASA Astrophysics Data System (ADS)

Schomerus, Volker; Sobko, Evgeny

2018-04-01

In this paper we develop further the relation between conformal four-point blocks involving external spinning fields and Calogero-Sutherland quantum mechanics with matrix-valued potentials. To this end, the analysis of [1] is extended to arbitrary dimensions and to the case of boundary two-point functions. In particular, we construct the potential for any set of external tensor fields. Some of the resulting Schrödinger equations are mapped explicitly to the known Casimir equations for 4-dimensional seed conformal blocks. Our approach furnishes solutions of Casimir equations for external fields of arbitrary spin and dimension in terms of functions on the conformal group. This allows us to reinterpret standard operations on conformal blocks in terms of group-theoretic objects. In particular, we shall discuss the relation between the construction of spinning blocks in any dimension through differential operators acting on seed blocks and the action of left/right invariant vector fields on the conformal group.

Influence of the time scale on the construction of financial networks.

PubMed

Emmert-Streib, Frank; Dehmer, Matthias

2010-09-30

In this paper we investigate the definition and formation of financial networks. Specifically, we study the influence of the time scale on their construction. For our analysis we use correlation-based networks obtained from the daily closing prices of stock market data. More precisely, we use the stocks that currently comprise the Dow Jones Industrial Average (DJIA) and estimate financial networks where nodes correspond to stocks and edges correspond to none vanishing correlation coefficients. That means only if a correlation coefficient is statistically significant different from zero, we include an edge in the network. This construction procedure results in unweighted, undirected networks. By separating the time series of stock prices in non-overlapping intervals, we obtain one network per interval. The length of these intervals corresponds to the time scale of the data, whose influence on the construction of the networks will be studied in this paper. Numerical analysis of four different measures in dependence on the time scale for the construction of networks allows us to gain insights about the intrinsic time scale of the stock market with respect to a meaningful graph-theoretical analysis.

Volcano-tectonic evolution of a linear volcanic ridge (Pico-Faial Ridge, Azores Triple Junction) assessed by paleomagnetic studies

NASA Astrophysics Data System (ADS)

Silva, Pedro F.; Henry, Bernard; Marques, Fernando O.; Hildenbrand, Anthony; Lopes, Ana; Madureira, Pedro; Madeira, José; Nunes, João C.; Roxerová, Zuzana

2018-02-01

The morphology of volcanic oceanic islands results from the interplay between constructive and destructive processes, and tectonics. In this study, the analysis of the paleomagnetic directions obtained on well-dated volcanic rocks is used as a tool to assess tilting related to tectonics and large-scale volcano instability along the Pico-Faial linear volcanic ridge (Azores Triple Junction, Central-North Atlantic). For this purpose, 530 specimens from 46 lava flows and one dyke from Pico and Faial islands were submitted to thermal and alternating magnetic fields demagnetizations. Detailed rock magnetic analyses, including thermomagnetic analyses and classical high magnetic field experiments revealed titanomagnetites with different Ti-content as the primary magnetic carrier, capable of recording stable remanent magnetizations. In both islands, the paleomagnetic analysis yields a Characteristic Remanent Magnetization, which presents island mean direction with normal and reversed polarities in agreement with the islands location and the age of the studied lava flows, indicating a primary thermo-remanent magnetization. Field observations and paleomagnetic data show that lava flows were emplaced on pre-existing slopes and were later affected by significant tilting. In Faial Island, magmatic inflation and normal faults making up an island-scale graben, can be responsible for the tilting. In Pico Island, inflation related to magma intrusion during flow emplacement can be at the origin of the inferred tilting, whereas gradual downward movement of the SE flank by slumping processes appears mostly translational.

Accident patterns for construction-related workers: a cluster analysis

NASA Astrophysics Data System (ADS)

Liao, Chia-Wen; Tyan, Yaw-Yauan

2012-01-01

The construction industry has been identified as one of the most hazardous industries. The risk of constructionrelated workers is far greater than that in a manufacturing based industry. However, some steps can be taken to reduce worker risk through effective injury prevention strategies. In this article, k-means clustering methodology is employed in specifying the factors related to different worker types and in identifying the patterns of industrial occupational accidents. Accident reports during the period 1998 to 2008 are extracted from case reports of the Northern Region Inspection Office of the Council of Labor Affairs of Taiwan. The results show that the cluster analysis can indicate some patterns of occupational injuries in the construction industry. Inspection plans should be proposed according to the type of construction-related workers. The findings provide a direction for more effective inspection strategies and injury prevention programs.

Accident patterns for construction-related workers: a cluster analysis

NASA Astrophysics Data System (ADS)

Liao, Chia-Wen; Tyan, Yaw-Yauan

2011-12-01

The construction industry has been identified as one of the most hazardous industries. The risk of constructionrelated workers is far greater than that in a manufacturing based industry. However, some steps can be taken to reduce worker risk through effective injury prevention strategies. In this article, k-means clustering methodology is employed in specifying the factors related to different worker types and in identifying the patterns of industrial occupational accidents. Accident reports during the period 1998 to 2008 are extracted from case reports of the Northern Region Inspection Office of the Council of Labor Affairs of Taiwan. The results show that the cluster analysis can indicate some patterns of occupational injuries in the construction industry. Inspection plans should be proposed according to the type of construction-related workers. The findings provide a direction for more effective inspection strategies and injury prevention programs.

Evaluating measurement models in clinical research: covariance structure analysis of latent variable models of self-conception.

PubMed

Hoyle, R H

1991-02-01

Indirect measures of psychological constructs are vital to clinical research. On occasion, however, the meaning of indirect measures of psychological constructs is obfuscated by statistical procedures that do not account for the complex relations between items and latent variables and among latent variables. Covariance structure analysis (CSA) is a statistical procedure for testing hypotheses about the relations among items that indirectly measure a psychological construct and relations among psychological constructs. This article introduces clinical researchers to the strengths and limitations of CSA as a statistical procedure for conceiving and testing structural hypotheses that are not tested adequately with other statistical procedures. The article is organized around two empirical examples that illustrate the use of CSA for evaluating measurement models with correlated error terms, higher-order factors, and measured and latent variables.

Fluorescein diacetate for determination of cell viability in 3D fibroblast-collagen-GAG constructs.

PubMed

Powell, Heather M; Armour, Alexis D; Boyce, Steven T

2011-01-01

Quantification of cell viability and distribution within engineered tissues currently relies on representative histology, phenotypic assays, and destructive assays of viability. To evaluate uniformity of cell density throughout 3D collagen scaffolds prior to in vivo use, a nondestructive, field assessment of cell viability is advantageous. Here, we describe a field measure of cell viability in lyophilized collagen-glycosaminoglycan (C-GAG) scaffolds in vitro using fluorescein diacetate (FdA). Fibroblast-C-GAG constructs are stained 1 day after cellular inoculation using 0.04 mg/ml FdA followed by exposure to 366 nm UV light. Construct fluorescence quantified using Metamorph image analysis is correlated with inoculation density, MTT values, and histology of corresponding biopsies. Construct fluorescence correlates significantly with inoculation density (p  <  0.001) and MTT values (p  <  0.001) of biopsies collected immediately after FdA staining. No toxicity is detected in the constructs, as measured by MTT assay before and after the FdA assay at different time points; normal in vitro histology is demonstrated for the FdA-exposed constructs. In conclusion, measurement of intracellular fluorescence with FdA allows for the early, comprehensive measurement of cellular distributions and viability in engineered tissue.

Meaning of leprosy for people who have experienced treatment during the sulfonic and multidrug therapy periods 1

PubMed Central

Santos, Karen da Silva; Fortuna, Cinira Magali; Santana, Fabiana Ribeiro; Gonçalves, Marlene Fagundes Carvalho; Marciano, Franciele Maia; Matumoto, Silvia

2015-01-01

Abstract Objective: to analyze the meanings of leprosy for people treated during the sulfonic and multidrug therapy periods. Method: qualitative nature study based on the Vigotski's historical-cultural approach, which guided the production and analysis of data. It included eight respondents who have had leprosy and were submitted to sulfonic and multidrug therapy treatments. The participants are also members of the Movement for Reintegration of People Affected by Leprosy. Results: the meanings were organized into three meaning cores: spots on the body: something is out of order; leprosy or hanseniasis? and leprosy from the inclusion in the Movement for Reintegration of People Affected by Leprosy. Conclusion: the meanings of leprosy for people submitted to both regimens point to a complex construction thereof, indicating differences and similarities in both treatments. Health professionals may contribute to the change of the meanings, since these are socially constructed and the changes are continuous. PMID:26444163

Mean-field models for heterogeneous networks of two-dimensional integrate and fire neurons.

PubMed

Nicola, Wilten; Campbell, Sue Ann

2013-01-01

We analytically derive mean-field models for all-to-all coupled networks of heterogeneous, adapting, two-dimensional integrate and fire neurons. The class of models we consider includes the Izhikevich, adaptive exponential and quartic integrate and fire models. The heterogeneity in the parameters leads to different moment closure assumptions that can be made in the derivation of the mean-field model from the population density equation for the large network. Three different moment closure assumptions lead to three different mean-field systems. These systems can be used for distinct purposes such as bifurcation analysis of the large networks, prediction of steady state firing rate distributions, parameter estimation for actual neurons and faster exploration of the parameter space. We use the mean-field systems to analyze adaptation induced bursting under realistic sources of heterogeneity in multiple parameters. Our analysis demonstrates that the presence of heterogeneity causes the Hopf bifurcation associated with the emergence of bursting to change from sub-critical to super-critical. This is confirmed with numerical simulations of the full network for biologically reasonable parameter values. This change decreases the plausibility of adaptation being the cause of bursting in hippocampal area CA3, an area with a sizable population of heavily coupled, strongly adapting neurons.

Mean-field models for heterogeneous networks of two-dimensional integrate and fire neurons

PubMed Central

Nicola, Wilten; Campbell, Sue Ann

2013-01-01

We analytically derive mean-field models for all-to-all coupled networks of heterogeneous, adapting, two-dimensional integrate and fire neurons. The class of models we consider includes the Izhikevich, adaptive exponential and quartic integrate and fire models. The heterogeneity in the parameters leads to different moment closure assumptions that can be made in the derivation of the mean-field model from the population density equation for the large network. Three different moment closure assumptions lead to three different mean-field systems. These systems can be used for distinct purposes such as bifurcation analysis of the large networks, prediction of steady state firing rate distributions, parameter estimation for actual neurons and faster exploration of the parameter space. We use the mean-field systems to analyze adaptation induced bursting under realistic sources of heterogeneity in multiple parameters. Our analysis demonstrates that the presence of heterogeneity causes the Hopf bifurcation associated with the emergence of bursting to change from sub-critical to super-critical. This is confirmed with numerical simulations of the full network for biologically reasonable parameter values. This change decreases the plausibility of adaptation being the cause of bursting in hippocampal area CA3, an area with a sizable population of heavily coupled, strongly adapting neurons. PMID:24416013

Exploring the Impact of Identity on the Experiences of Entry-Level Men in Student Affairs

ERIC Educational Resources Information Center

Calhoun, Daniel W.

2010-01-01

The purpose of this study was to understand the experiences of men at the entry-level of the student affairs profession. Using the concepts found in the existing literature related to gender identity as a framework, the research was focused upon the meanings constructed by entry-level men within the field of student affairs and how those meanings…

10 CFR 431.102 - Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water...

Code of Federal Regulations, 2011 CFR

2011-01-01

... section 340 of the Act, 42 U.S.C. 6311. ASTM-D-2156-80 means the test standard published in 1980 by the... that is industrial equipment, including products meeting this description that are designed to heat... sections and does not include a boiler that is custom designed and field constructed. If the boiler is...

Multimodal Discourse Analysis of the Movie "Argo"

ERIC Educational Resources Information Center

Bo, Xu

2018-01-01

Based on multimodal discourse theory, this paper makes a multimodal discourse analysis of some shots in the movie "Argo" from the perspective of context of culture, context of situation and meaning of image. Results show that this movie constructs multimodal discourse through particular context, language and image, and successfully…

Learning with Concept and Knowledge Maps: A Meta-Analysis

ERIC Educational Resources Information Center

Nesbit, John C.; Adesope, Olusola O.

2006-01-01

This meta-analysis reviews experimental and quasi-experimental studies in which students learned by constructing, modifying, or viewing node-link diagrams. Following an exhaustive search for studies meeting specified design criteria, 67 standardized mean difference effect sizes were extracted from 55 studies involving 5,818 participants. Students…

Through the Drinking Glass: An Analysis of the Cultural Meanings of College Drinking

ERIC Educational Resources Information Center

Tan, Andy Soon Leong

2012-01-01

College drinking and its adverse consequences on students' health and safety are important public health concerns in the USA. Thus far, there is little attention on exploring and addressing the cultural dimensions of college drinking. This study examines the construction of meaning of drinking among students to understand their perspectives of the…

Grades Five and Six Students' Representation of Meaning in Collaborative Wiki Writing

ERIC Educational Resources Information Center

Peterson, Shelley Stagg; Portier, Christine

2014-01-01

This paper examined grades 5 and 6 students' participation in wikis while writing reports on social studies topics. An analysis of eight wikis showed that students represented meanings they had constructed about their topics by engaging in knowledge telling practices (e.g., introducing, stating, or repeating information or an idea and developing…

Thermal structure of Sikhote Alin and adjacent areas based on spectral analysis of the anomalous magnetic field

NASA Astrophysics Data System (ADS)

Didenko, A. N.; Nosyrev, M. Yu.; Shevchenko, B. F.; Gilmanova, G. Z.

2017-11-01

The depth of the base of the magnetoactive layer and the geothermal gradient in the Sikhote Alin crust are estimated based on a method determining the Curie depth point of magnetoactive masses by using spectral analysis of the anomalous magnetic field. A detailed map of the geothermal gradient is constructed for the first time for the Sikhote Alin and adjacent areas of the Central Asian belt. Analysis of this map shows that the zones with a higher geothermal gradient geographically fit the areas with a higher level of seismicity.

Lie symmetry analysis, Bäcklund transformations, and exact solutions of a (2 + 1)-dimensional Boiti-Leon-Pempinelli system

NASA Astrophysics Data System (ADS)

Zhao, Zhonglong; Han, Bo

2017-10-01

In this paper, the Lie symmetry analysis method is employed to investigate the Lie point symmetries and the one-parameter transformation groups of a (2 + 1)-dimensional Boiti-Leon-Pempinelli system. By using Ibragimov's method, the optimal system of one-dimensional subalgebras of this system is constructed. Truncated Painlevé analysis is used for deriving the Bäcklund transformation. The method of constructing lump-type solutions of integrable equations by means of Bäcklund transformation is first presented. Meanwhile, the lump-type solutions of the (2 + 1)-dimensional Boiti-Leon-Pempinelli system are obtained. The lump-type wave is one kind of rogue wave. The fusion-type N-solitary wave solutions are also constructed. In addition, this system is integrable in terms of the consistent Riccati expansion method.

Program for Editing Spacecraft Command Sequences

NASA Technical Reports Server (NTRS)

Gladden, Roy; Waggoner, Bruce; Kordon, Mark; Hashemi, Mahnaz; Hanks, David; Salcedo, Jose

2006-01-01

Sequence Translator, Editor, and Expander Resource (STEER) is a computer program that facilitates construction of sequences and blocks of sequences (hereafter denoted generally as sequence products) for commanding a spacecraft. STEER also provides mechanisms for translating among various sequence product types and quickly expanding activities of a given sequence in chronological order for review and analysis of the sequence. To date, construction of sequence products has generally been done by use of such clumsy mechanisms as text-editor programs, translating among sequence product types has been challenging, and expanding sequences to time-ordered lists has involved arduous processes of converting sequence products to "real" sequences and running them through Class-A software (defined, loosely, as flight and ground software critical to a spacecraft mission). Also, heretofore, generating sequence products in standard formats has been troublesome because precise formatting and syntax are required. STEER alleviates these issues by providing a graphical user interface containing intuitive fields in which the user can enter the necessary information. The STEER expansion function provides a "quick and dirty" means of seeing how a sequence and sequence block would expand into a chronological list, without need to use of Class-A software.

[Information and information technology in health: contemporary health kaleidoscope].

PubMed

de Moraes, Ilara Hämmerli Sozzi; de Gómez, Maria Nélida González

2007-01-01

This essay is based on the assumption that current practices and knowledge of Information and Information Technology in Health are unable to deal with the complexity of the health/disease/care processes and contemporary problems that must be overcome, curbing the expansion of the response capacity of the Brazilian State. It aims to further explore the understanding of the roots and determining factors behind these constraints, analyzing alternatives for confronting them that depend less on location-specific initiatives in the field of information and more - among others - on the adoption of new benchmarks, starting with the meaning and concept of Health. It identifies the existence of an 'information and information technology interfield' that arises from an epistemology based on a transdisciplinary approach, as well as the consolidation of a political and historical process of institutional construction, an area endowed with power and relevance: a political-epistemological interfield. The analysis goes on through an exploratory study of the social, political and epistemological processes found in the historical construction health information networks established by Science and Technology in health, as well as by healthcare systems and services, in addition to social, political and economic information.

M2 Internal Tides and Their Observed Wavenumber Spectra from Satellite Altimetry*

NASA Technical Reports Server (NTRS)

Ray, R. D.; Zaron, E. D.

2015-01-01

A near-global chart of surface elevations associated with the stationary M2 internal tide is empirically constructed from multi-mission satellite altimeter data. An advantage of a strictly empirical mapping approach is that results are independent of assumptions about ocean wave dynamics and, in fact, can be used to test such assumptions. A disadvantage is that present-day altimeter coverage is only marginally adequate to support mapping such short-wavelength features. Moreover, predominantly north-south ground-track orientations and contamination from nontidal oceanographic variability can lead to deficiencies in mapped tides. Independent data from Cryosphere Satellite-2 (CryoSat-2) and other altimeters are used to test the solutions and show positive reduction in variance except in regions of large mesoscale variability. The tidal fields are subjected to two-dimensional wavenumber spectral analysis, which allows for the construction of an empirical map of modal wavelengths. Mode-1 wavelengths show good agreement with theoretical wavelengths calculated from the ocean's mean stratification, with a few localized exceptions (e.g., Tasman Sea). Mode-2 waves are detectable in much of the ocean, with wavelengths in reasonable agreement with theoretical expectations, but their spectral signatures grow too weak to map in some regions.

Why developmental niche construction is not selective niche construction: and why it matters.

PubMed

Stotz, Karola

2017-10-06

In the last decade, niche construction has been heralded as the neglected process in evolution. But niche construction is just one way in which the organism's interaction with and construction of the environment can have potential evolutionary significance. The constructed environment does not just select for , it also produces new variation. Nearly 3 decades ago, and in parallel with Odling-Smee's article 'Niche-constructing phenotypes', West and King introduced the 'ontogenetic niche' to give the phenomena of exo genetic inheritance a formal name. Since then, a range of fields in the life sciences and medicine has amassed evidence that parents influence their offspring by means other than DNA (parental effects), and proposed mechanisms for how heritable variation can be environmentally induced and developmentally regulated. The concept of 'developmental niche construction' (DNC) elucidates how a diverse range of mechanisms contributes to the transgenerational transfer of developmental resources. My most central of claims is that whereas the selective niche of niche construction theory is primarily used to explain the active role of the organism in its selective environment, DNC is meant to indicate the active role of the organism in its developmental environment. The paper highlights the differences between the construction of the selective and the developmental niche, and explores the overall significance of DNC for evolutionary theory.

On the nature of a supposed water model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heckmann, Lotta, E-mail: lotta@fkp.tu-darmstadt.de; Drossel, Barbara

2014-08-15

A cell model that has been proposed by Stanley and Franzese in 2002 for modeling water is based on Potts variables that represent the possible orientations of bonds between water molecules. We show that in the liquid phase, where all cells are occupied by a molecule, the Hamiltonian of the cell model can be rewritten as a Hamiltonian of a conventional Potts model, albeit with two types of coupling constants. We argue that such a model, while having a first-order phase transition, cannot display the critical end point that is postulated for the phase transition between a high- and low-densitymore » liquid. A closer look at the mean-field calculations that claim to find such an end point in the cell model reveals that the mean-field theory is constructed such that the symmetry constraints on the order parameter are violated. This is equivalent to introducing an external field. The introduction of such a field can be given a physical justification due to the fact that water does not have the type of long-range order occurring in the Potts model.« less

Validation of learning style measures: implications for medical education practice.

PubMed

Chapman, Dane M; Calhoun, Judith G

2006-06-01

It is unclear which learners would most benefit from the more individualised, student-structured, interactive approaches characteristic of problem-based and computer-assisted learning. The validity of learning style measures is uncertain, and there is no unifying learning style construct identified to predict such learners. This study was conducted to validate learning style constructs and to identify the learners most likely to benefit from problem-based and computer-assisted curricula. Using a cross-sectional design, 3 established learning style inventories were administered to 97 post-Year 2 medical students. Cognitive personality was measured by the Group Embedded Figures Test, information processing by the Learning Styles Inventory, and instructional preference by the Learning Preference Inventory. The 11 subscales from the 3 inventories were factor-analysed to identify common learning constructs and to verify construct validity. Concurrent validity was determined by intercorrelations of the 11 subscales. A total of 94 pre-clinical medical students completed all 3 inventories. Five meaningful learning style constructs were derived from the 11 subscales: student- versus teacher-structured learning; concrete versus abstract learning; passive versus active learning; individual versus group learning, and field-dependence versus field-independence. The concurrent validity of 10 of 11 subscales was supported by correlation analysis. Medical students most likely to thrive in a problem-based or computer-assisted learning environment would be expected to score highly on abstract, active and individual learning constructs and would be more field-independent. Learning style measures were validated in a medical student population and learning constructs were established for identifying learners who would most likely benefit from a problem-based or computer-assisted curriculum.

Content analysis as a means of exploring research opportunities from a conference programme.

PubMed

Fourie, Ina

2012-09-01

Health librarians should keep up-to-date in a dynamic environment and accept the importance of continuing personal development (CPD) and growth in their critical reflection and creative thinking skills. They also need to acknowledge the potential value of research activity and the challenges of ongoing improvement and development. Conference programmes may prove a useful source of stimulation, especially if supplemented by creativity techniques, action research and the ideal of 'finding flow'. The article analyses the themes and papers presented at the 10th International Conference on International Medical Librarianship (ICML) to identify opportunities for further research, literature reviews, assessment of practices and services, etc. Content analysis approach to conference papers and suggestions for further action including supplementing with techniques of creativity and group input. A fairly extensive list of further actions (although not intended to be exhaustive) is suggested for the sixteen conference themes. Although subjective, the list might help to stimulate growth in research on health librarianship and demonstrate how one source of stimulation--conference programmes (regularly presented to medical library communities)--can be used. Content analysis has proven a constructive means of generating research questions from a conference programme. Content analysis and other methods aimed at stimulating creative and progressive thinking, including brainstorming, force field analysis, De Bono's 6 hats, creative swiping and creative visualisation, may prove equally useful and require further investigation. To ensure an ongoing cycle, these can be linked to action research. © 2012 The authors. Health Information and Libraries Journal © 2012 Health Libraries Group.

On the Helicity of Open Magnetic Fields

NASA Astrophysics Data System (ADS)

Prior, C.; Yeates, A. R.

2014-06-01

We reconsider the topological interpretation of magnetic helicity for magnetic fields in open domains, and relate this to the relative helicity. Specifically, our domains stretch between two parallel planes, and each of these ends may be magnetically open. It is demonstrated that, while the magnetic helicity is gauge-dependent, its value in any gauge may be physically interpreted as the average winding number among all pairs of field lines with respect to some orthonormal frame field. In fact, the choice of gauge is equivalent to the choice of reference field in the relative helicity, meaning that the magnetic helicity is no less physically meaningful. We prove that a particular gauge always measures the winding with respect to a fixed frame, and propose that this is normally the best choice. For periodic fields, this choice is equivalent to measuring relative helicity with respect to a potential reference field. However, for aperiodic fields, we show that the potential field can be twisted. We prove by construction that there always exists a possible untwisted reference field.

Rasch Model Based Analysis of the Force Concept Inventory

ERIC Educational Resources Information Center

Planinic, Maja; Ivanjek, Lana; Susac, Ana

2010-01-01

The Force Concept Inventory (FCI) is an important diagnostic instrument which is widely used in the field of physics education research. It is therefore very important to evaluate and monitor its functioning using different tools for statistical analysis. One of such tools is the stochastic Rasch model, which enables construction of linear…

Narratives as Zones of Dialogic Constructions: A Bakhtinian Approach to Data in Qualitative Research

ERIC Educational Resources Information Center

Vitanova, Gergana

2013-01-01

Narratives have become increasingly important in the field of applied linguistics, as recent publications have illustrated, yet narrative analysis could still be considered undertheorized. This article outlines a specific, dialogical approach to the narrative analysis of data in qualitative research. Building on Bakhtin's notion of dialogue,…

Classification of hospital pathways in the management of cancer: application to lung cancer in the region of burgundy.

PubMed

Nuemi, G; Afonso, F; Roussot, A; Billard, L; Cottenet, J; Combier, E; Diday, E; Quantin, C

2013-10-01

The evaluation of national cancer plans is an important aspect of their implementation. For this evaluation, the principal actors in the field (doctors, nurses, etc.) as well as decision-makers must have access to information that is reliable, synthetic and easy to interpret, and which reflects the implementation process in the field. We propose here a methodology to make this type of information available in the context of reducing inequalities with regard to access to healthcare for patients with lung cancer in the region of Burgundy. We used the national medico-administrative DRG-type database, which gathers together all hospital stays. By using this database, it was possible to identify and reconstruct the care management history of these patients. That is, by linking together all attended hospitals, sorted chronologically. Eligible patients were at least 18 years old, whatever the gender and had undergone surgery for their lung cancer. They had to be residents of Burgundy at the time of the first operation between 2006 and 2008. Patient's pathway was defined as the sequence of all attended hospitals (hospital stays) during the year of follow up linked together using an anonymised patient identifier. We then constructed a pathway typology of pathway using an unsupervised clustering method, and conducted a spatial analysis of this typology. Between 2006 and 2008, we selected 495 patients in the 4 administrative departments of the Burgundy region. They accounted for a total of 3821 stays during the year of follow-up. There were 393 men (79%) and the mean age was 64 (95% confidence interval: 63-65) years. We reconstructed 94 pathways (about five per patient). Here, neighbourhood's cares accounted for 41% of them, while 44% included a surgical intervention outside the region of Burgundy. We constructed a pathway typology with five classes. Spatial analysis showed that the vast majority of initial surgeries took place in the major regional centres. The construction of a pathway typology leads to better understanding of the reasoning that lies behind the movements of patients. It opens the way for analysis of the collaboration between the different healthcares establishments attended, which should bring to light associations that need to be developed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Systematic Review of Methods in Low-Consensus Fields: Supporting Commensuration through `Construct-Centered Methods Aggregation' in the Case of Climate Change Vulnerability Research.

PubMed

Delaney, Aogán; Tamás, Peter A; Crane, Todd A; Chesterman, Sabrina

2016-01-01

There is increasing interest in using systematic review to synthesize evidence on the social and environmental effects of and adaptations to climate change. Use of systematic review for evidence in this field is complicated by the heterogeneity of methods used and by uneven reporting. In order to facilitate synthesis of results and design of subsequent research a method, construct-centered methods aggregation, was designed to 1) provide a transparent, valid and reliable description of research methods, 2) support comparability of primary studies and 3) contribute to a shared empirical basis for improving research practice. Rather than taking research reports at face value, research designs are reviewed through inductive analysis. This involves bottom-up identification of constructs, definitions and operationalizations; assessment of concepts' commensurability through comparison of definitions; identification of theoretical frameworks through patterns of construct use; and integration of transparently reported and valid operationalizations into ideal-type research frameworks. Through the integration of reliable bottom-up inductive coding from operationalizations and top-down coding driven from stated theory with expert interpretation, construct-centered methods aggregation enabled both resolution of heterogeneity within identically named constructs and merging of differently labeled but identical constructs. These two processes allowed transparent, rigorous and contextually sensitive synthesis of the research presented in an uneven set of reports undertaken in a heterogenous field. If adopted more broadly, construct-centered methods aggregation may contribute to the emergence of a valid, empirically-grounded description of methods used in primary research. These descriptions may function as a set of expectations that improves the transparency of reporting and as an evolving comprehensive framework that supports both interpretation of existing and design of future research.

Systematic Review of Methods in Low-Consensus Fields: Supporting Commensuration through `Construct-Centered Methods Aggregation’ in the Case of Climate Change Vulnerability Research

PubMed Central

Crane, Todd A.; Chesterman, Sabrina

2016-01-01

There is increasing interest in using systematic review to synthesize evidence on the social and environmental effects of and adaptations to climate change. Use of systematic review for evidence in this field is complicated by the heterogeneity of methods used and by uneven reporting. In order to facilitate synthesis of results and design of subsequent research a method, construct-centered methods aggregation, was designed to 1) provide a transparent, valid and reliable description of research methods, 2) support comparability of primary studies and 3) contribute to a shared empirical basis for improving research practice. Rather than taking research reports at face value, research designs are reviewed through inductive analysis. This involves bottom-up identification of constructs, definitions and operationalizations; assessment of concepts’ commensurability through comparison of definitions; identification of theoretical frameworks through patterns of construct use; and integration of transparently reported and valid operationalizations into ideal-type research frameworks. Through the integration of reliable bottom-up inductive coding from operationalizations and top-down coding driven from stated theory with expert interpretation, construct-centered methods aggregation enabled both resolution of heterogeneity within identically named constructs and merging of differently labeled but identical constructs. These two processes allowed transparent, rigorous and contextually sensitive synthesis of the research presented in an uneven set of reports undertaken in a heterogenous field. If adopted more broadly, construct-centered methods aggregation may contribute to the emergence of a valid, empirically-grounded description of methods used in primary research. These descriptions may function as a set of expectations that improves the transparency of reporting and as an evolving comprehensive framework that supports both interpretation of existing and design of future research. PMID:26901409

Perception of Construction Participants in Construction delays: A case study in Tamilnadu, India.

NASA Astrophysics Data System (ADS)

Rathinakumar, V.; Vignesh, T.; Dhivagar, K.

2017-07-01

Delays in the construction industry are universal fact, which affects the construction participants. The research work spotlights on determining the prevailing delays in the cities of Tamil Nadu, as perceived by the participants. After a few field level interactions, a questionnaire was framed and administered to the participants i.e., Consultants (50 Nos.), contractors (50 Nos.) and clients (150 Nos.) to understand their perception on the causes of delays. The factors for delay was categorized into 4 groups say Improper project planning, Design related issues, Finance related issues and Resource related issues. The responses were analysed using the SPSS software by applying ANOVA and Regression analysis. From the analysis, it was found that the personal financial problems of the client dominantly affect the entire construction progress and the subsequent design changes by the clients, Inadequate early project planning, labour related issues. Also, the delay groups were found to be the improper project planning and the Resource related issues.

MEAN-FIELD SOLAR DYNAMO MODELS WITH A STRONG MERIDIONAL FLOW AT THE BOTTOM OF THE CONVECTION ZONE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pipin, V. V.; Kosovichev, A. G.

2011-09-01

This paper presents a study of kinematic axisymmetric mean-field dynamo models for the case of meridional circulation with a deep-seated stagnation point and a strong return flow at the bottom of the convection zone. This kind of circulation follows from mean-field models of the angular momentum balance in the solar convection zone. The dynamo models include turbulent sources of the large-scale poloidal magnetic field production due to kinetic helicity and a combined effect due to the Coriolis force and large-scale electric current. In these models the toroidal magnetic field, which is responsible for sunspot production, is concentrated at the bottommore » of the convection zone and is transported to low-latitude regions by a meridional flow. The meridional component of the poloidal field is also concentrated at the bottom of the convection zone, while the radial component is concentrated in near-polar regions. We show that it is possible for this type of meridional circulation to construct kinematic dynamo models that resemble in some aspects the sunspot magnetic activity cycle. However, in the near-equatorial regions the phase relation between the toroidal and poloidal components disagrees with observations. We also show that the period of the magnetic cycle may not always monotonically decrease with the increase of the meridional flow speed. Thus, for further progress it is important to determine the structure of the meridional circulation, which is one of the critical properties, from helioseismology observations.« less

Ward identities and chiral anomalies for coupled fermionic chains

DOE Office of Scientific and Technical Information (OSTI.GOV)

Costa, L. C.; Ferraz, A.; Mastropietro, Vieri

2013-12-15

Coupled fermionic chains are usually described by an effective model written in terms of bonding and anti-bonding fermionic fields with linear dispersion in the vicinities of the respective Fermi points. We derive for the first time exact Ward Identities (WI) for this model, proving the existence of chiral anomalies which verify the Adler-Bardeen non-renormalization property. Such WI are expected to play a crucial role in the understanding of the thermodynamic properties of the system. Our results are non-perturbative and are obtained analyzing Grassmann functional integrals by means of constructive quantum field theory methods.

Determination of Ground Heat Exchangers Temperature Field in Geothermal Heat Pumps

NASA Astrophysics Data System (ADS)

Zhurmilova, I.; Shtym, A.

2017-11-01

For the heating and cooling supply of buildings and constructions geothermal heat pumps using low-potential ground energy are applied by means of ground exchangers. The process of heat transfer in a system of ground exchangers is a phenomenon of complex heat transfer. The paper presents a mathematical modeling of heat exchange processes, the temperature fields are built which are necessary for the determination of the ground array that ensures an adequate supply of low potential energy excluding the freezing of soil around the pipes in the ground heat exchangers and guaranteeing a reliable operation of geothermal heat pumps.

Electromagnetic induction pump for pumping liquid metals and other conductive liquids

DOEpatents

Smither, R.K.

1993-05-11

An electromagnetic induction pump is described in which an electrically conductive liquid is made to flow by means of a force created by interaction of a permanent magnetic field and a DC current. The pump achieves high efficiency through combination of: powerful permanent magnet materials which provide a high strength field that is uniform and constant; steel tubing formed into a coil which is constructed to carry conducting liquids with minimal electrical resistance and heat; and application of a voltage to induce a DC current which continuously produces a force in the direction of the desired flow.

Electromagnetic induction pump for pumping liquid metals and other conductive liquids

DOEpatents

Smither, Robert K.

1993-01-01

An electromagnetic induction pump in which an electrically conductive liquid is made to flow by means of a force created by interaction of a permanent magnetic field and a DC current. The pump achieves high efficiency through combination of: powerful permanent magnet materials which provide a high strength field that is uniform and constant; steel tubing formed into a coil which is constructed to carry conducting liquids with minimal electrical resistance and heat; and application of a voltage to induce a DC current which continuously produces a force in the direction of the desired flow.

Mean gravity anomalies from a combination of Apollo/ATS 6 and GEOS 3/ATS 6 SST tracking campaigns. [Satellite to Satellite Tracking

NASA Technical Reports Server (NTRS)

Kahn, W. D.; Klosko, S. M.; Wells, W. T.

1982-01-01

Advances in satellite tracking data accuracy and coverage over the past 15 years have led to major improvements in global geopotential models. But the spacial resolution of the gravity field obtained solely from satellite dynamics sensed by tracking data is still of the order of 1000 km. Attention is given to an approach which will provide information regarding the fine structure of the gravity field on the basis of an application of local corrections to the global field. According to this approach, a basic satellite to satellite tracked (SST) range-rate measurement is constructed from the link between a ground station, a geosynchronous satellite (ATS 6), and a near-earth satellite (Apollo or GEOS 3). Attention is given to a mathematical model, the simulation of SST gravity anomaly estimation accuracies, a gravity anomaly estimation from GEOS 3/ATS 6 and Apollo/ATS 6 SST observations, and an evaluation of the mean gravity anomalies determined from SST.

The New Field Quantities and the Poynting Theorem in Material Medium with Magnetic Monopoles

NASA Astrophysics Data System (ADS)

Zor, Ömer

2016-12-01

The duality transformation was used to define the polarization mechanisms that arise from magnetic monopoles. Then, a dimensional analysis was conducted to describe the displacement and magnetic intensity vectors (constitutive equations) in SI units. Finally, symmetric Maxwell equations in a material medium with new field quantities were introduced. Hence, the Lorentz force and the Poynting theorem were defined with these new field quantities, and many possible definitions of them were constructed.

From Theory to Practice: A Quantitative Content Analysis of Adult Education's Language on Meaning Making

ERIC Educational Resources Information Center

Roessger, Kevin M.

2017-01-01

Translating theory to practice has been a historical concern of adult education. It remains unclear, though, if adult education's theoretical and epistemological focus on meaning making transcends the academy. A manifest content analysis was conducted to determine if the frequency of meaning making language differed between the field's U.S.…

Comparative study of the requantization of the time-dependent mean field for the dynamics of nuclear pairing

NASA Astrophysics Data System (ADS)

Ni, Fang; Nakatsukasa, Takashi

2018-04-01

To describe quantal collective phenomena, it is useful to requantize the time-dependent mean-field dynamics. We study the time-dependent Hartree-Fock-Bogoliubov (TDHFB) theory for the two-level pairing Hamiltonian, and compare results of different quantization methods. The one constructing microscopic wave functions, using the TDHFB trajectories fulfilling the Einstein-Brillouin-Keller quantization condition, turns out to be the most accurate. The method is based on the stationary-phase approximation to the path integral. We also examine the performance of the collective model which assumes that the pairing gap parameter is the collective coordinate. The applicability of the collective model is limited for the nuclear pairing with a small number of single-particle levels, because the pairing gap parameter represents only a half of the pairing collective space.

Core surface magnetic field evolution 2000-2010

NASA Astrophysics Data System (ADS)

Finlay, C. C.; Jackson, A.; Gillet, N.; Olsen, N.

2012-05-01

We present new dedicated core surface field models spanning the decade from 2000.0 to 2010.0. These models, called gufm-sat, are based on CHAMP, Ørsted and SAC-C satellite observations along with annual differences of processed observatory monthly means. A spatial parametrization of spherical harmonics up to degree and order 24 and a temporal parametrization of sixth-order B-splines with 0.25 yr knot spacing is employed. Models were constructed by minimizing an absolute deviation measure of misfit along with measures of spatial and temporal complexity at the core surface. We investigate traditional quadratic or maximum entropy regularization in space, and second or third time derivative regularization in time. Entropy regularization allows the construction of models with approximately constant spectral slope at the core surface, avoiding both the divergence characteristic of the crustal field and the unrealistic rapid decay typical of quadratic regularization at degrees above 12. We describe in detail aspects of the models that are relevant to core dynamics. Secular variation and secular acceleration are found to be of lower amplitude under the Pacific hemisphere where the core field is weaker. Rapid field evolution is observed under the eastern Indian Ocean associated with the growth and drift of an intense low latitude flux patch. We also find that the present axial dipole decay arises from a combination of subtle changes in the southern hemisphere field morphology.

Melatonin secretion and puberty in female lambs exposed to environmental electric and magnetic fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, J.M. Jr.; Stormshak, F.; Thompson, J.M.

This study determined whether chronic exposure of female lambs to the electric and magnetic fields (EMF) of a high voltage transmission line can alter pineal secretion of melatonin and the normal occurrence of puberty. Twenty female Suffolk lambs were assigned randomly in equal numbers to a control and a treatment group. Treatment from 2 to 10 mo of age consisted of continuous exposure within the electrical environment of a 500-kV transmission line (mean electric field 6 kV/m, mean magnetic field 40 mG). Treated lambs were penned directly beneath the transmission line; control lambs were maintained in a pen of similarmore » construction 229 m from the line where EMF were at ambient levels (mean electric field < 10 V/m, mean magnetic field < 0.3 mG). Melatonin was analyzed by RIA in serum of blood samples collected at 0.5-3-h intervals over eight 48-h periods. To assess attainment of puberty, serum concentrations of progesterone were determined by RIA from blood samples collected twice weekly beginning at 19 wk of age. Concentrations of circulating melatonin in control and treated lambs were low during daylight hours and increased during nighttime hours. The characteristic pattern of melatonin secretion during nighttime (amplitude, phase, and duration) did not differ between control and treatment groups. Age at puberty and number of subsequent estrous cycles also did not differ between groups. These data suggest that chronic exposure of developing female sheep to 60-Hz environmental EMF does not affect the mechanisms underlying the generation of the circadian pattern of melatonin secretion or the mechanisms involved in the onset of reproductive activity.« less

New developments in spatial interpolation methods of Sea-Level Anomalies in the Mediterranean Sea

NASA Astrophysics Data System (ADS)

Troupin, Charles; Barth, Alexander; Beckers, Jean-Marie; Pascual, Ananda

2014-05-01

The gridding of along-track Sea-Level Anomalies (SLA) measured by a constellation of satellites has numerous applications in oceanography, such as model validation, data assimilation or eddy tracking. Optimal Interpolation (OI) is often the preferred method for this task, as it leads to the lowest expected error and provides an error field associated to the analysed field. However, the numerical cost of the method may limit its utilization in situations where the number of data points is significant. Furthermore, the separation of non-adjacent regions with OI requires adaptation of the code, leading to a further increase of the numerical cost. To solve these issues, the Data-Interpolating Variational Analysis (DIVA), a technique designed to produce gridded from sparse in situ measurements, is applied on SLA data in the Mediterranean Sea. DIVA and OI have been shown to be equivalent (provided some assumptions on the covariances are made). The main difference lies in the covariance function, which is not explicitly formulated in DIVA. The particular spatial and temporal distributions of measurements required adaptation in the Software tool (data format, parameter determinations, ...). These adaptation are presented in the poster. The daily analysed and error fields obtained with this technique are compared with available products such as the gridded field from the Archiving, Validation and Interpretation of Satellite Oceanographic data (AVISO) data server. The comparison reveals an overall good agreement between the products. The time evolution of the mean error field evidences the need of a large number of simultaneous altimetry satellites: in period during which 4 satellites are available, the mean error is on the order of 17.5%, while when only 2 satellites are available, the error exceeds 25%. Finally, we propose the use sea currents to improve the results of the interpolation, especially in the coastal area. These currents can be constructed from the bathymetry or extracted from a HF radar located in the Balearic Sea.

Motor vehicle crashes in roadway construction workzones: an analysis using narrative text from insurance claims.

PubMed

Sorock, G S; Ranney, T A; Lehto, M R

1996-01-01

Motor vehicle travel through roadway construction workzones has been shown to increase the risk of a crash. The number of workzones has increased due to recent congressional funding in 1991 for expanded roadway maintenance and repair. In this paper, we describe the characteristics and costs of motor vehicle crashes in roadway construction workzones. As opposed to using standard accident codes to identify accident types, automobile insurance claims files from 1990-93 were searched to identify records with the keyword "construction" in the accident narrative field. A total of 3,686 claims were used for the analysis of crashes. Keywords from the accident narrative field were used to identify five pre-crash vehicle activities and five crash types. We evaluated misclassification error by reading 560 randomly selected claims and found it to be only 5%. For each of four years, 1990-93, there was a total of 648,996,977 and 1,065 crashes, respectively. There was a 70% increase in the crash rate per 10,000 personal insured vehicles from 1990-93 (2.1-3.6). Most crashes (26%) involved a stopped or slowing vehicle in the workzone. The most common crash (31%) was a rear-end collision. The most costly pre-crash activity was a major judgment error on the part of a driver (n = 120, median cost = $2,628). An overturned vehicle was the most costly crash type (n = 16, median cost = $4,745). In summary, keyword text analysis of accident narrative data used in this study demonstrated its utility and potential for enhancing injury epidemiology. The results suggest interventions are needed to respond to growing traffic hazards in construction workzones.

Grain-size dynamics beneath mid-ocean ridges: Implications for permeability and melt extraction.

PubMed

Turner, Andrew J; Katz, Richard F; Behn, Mark D

2015-03-01

Grain size is an important control on mantle viscosity and permeability, but is difficult or impossible to measure in situ. We construct a two-dimensional, single phase model for the steady state mean grain size beneath a mid-ocean ridge. The mantle rheology is modeled as a composite of diffusion creep, dislocation creep, dislocation accommodated grain boundary sliding, and a plastic stress limiter. The mean grain size is calculated by the paleowattmeter relationship of Austin and Evans (2007). We investigate the sensitivity of our model to global variations in grain growth exponent, potential temperature, spreading-rate, and mantle hydration. We interpret the mean grain-size field in terms of its permeability to melt transport. The permeability structure due to mean grain size may be approximated as a high permeability region beneath a low permeability region. The transition between high and low permeability regions occurs across a boundary that is steeply inclined toward the ridge axis. We hypothesize that such a permeability structure generated from the variability of the mean grain size may focus melt toward the ridge axis, analogous to Sparks and Parmentier (1991)-type focusing. This focusing may, in turn, constrain the region where significant melt fractions are observed by seismic or magnetotelluric surveys. This interpretation of melt focusing via the grain-size permeability structure is consistent with MT observation of the asthenosphere beneath the East Pacific Rise. The grain-size field beneath MORs can vary over orders of magnitude The grain-size field affects the rheology and permeability of the asthenosphere The grain-size field may focus melt toward the ridge axis.

Fast orthogonal transforms and generation of Brownian paths

PubMed Central

Leobacher, Gunther

2012-01-01

We present a number of fast constructions of discrete Brownian paths that can be used as alternatives to principal component analysis and Brownian bridge for stratified Monte Carlo and quasi-Monte Carlo. By fast we mean that a path of length n can be generated in O(nlog(n)) floating point operations. We highlight some of the connections between the different constructions and we provide some numerical examples. PMID:23471545

Perturbative stability of SFT-based cosmological models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galli, Federico; Koshelev, Alexey S., E-mail: fgalli@tena4.vub.ac.be, E-mail: alexey.koshelev@vub.ac.be

2011-05-01

We review the appearance of multiple scalar fields in linearized SFT based cosmological models with a single non-local scalar field. Some of these local fields are canonical real scalar fields and some are complex fields with unusual coupling. These systems only admit numerical or approximate analysis. We introduce a modified potential for multiple scalar fields that makes the system exactly solvable in the cosmological context of Friedmann equations and at the same time preserves the asymptotic behavior expected from SFT. The main part of the paper consists of the analysis of inhomogeneous cosmological perturbations in this system. We show numericallymore » that perturbations corresponding to the new type of complex fields always vanish. As an example of application of this model we consider an explicit construction of the phantom divide crossing and prove the perturbative stability of this process at the linear order. The issue of ghosts and ways to resolve it are briefly discussed.« less

Modeling Water Temperature in the Yakima River, Washington, from Roza Diversion Dam to Prosser Dam, 2005-06

USGS Publications Warehouse

Voss, Frank D.; Curran, Christopher A.; Mastin, Mark C.

2008-01-01

A mechanistic water-temperature model was constructed by the U.S. Geological Survey for use by the Bureau of Reclamation for studying the effect of potential water management decisions on water temperature in the Yakima River between Roza and Prosser, Washington. Flow and water temperature data for model input were obtained from the Bureau of Reclamation Hydromet database and from measurements collected by the U.S. Geological Survey during field trips in autumn 2005. Shading data for the model were collected by the U.S. Geological Survey in autumn 2006. The model was calibrated with data collected from April 1 through October 31, 2005, and tested with data collected from April 1 through October 31, 2006. Sensitivity analysis results showed that for the parameters tested, daily maximum water temperature was most sensitive to changes in air temperature and solar radiation. Root mean squared error for the five sites used for model calibration ranged from 1.3 to 1.9 degrees Celsius (?C) and mean error ranged from ?1.3 to 1.6?C. The root mean squared error for the five sites used for testing simulation ranged from 1.6 to 2.2?C and mean error ranged from 0.1 to 1.3?C. The accuracy of the stream temperatures estimated by the model is limited by four errors (model error, data error, parameter error, and user error).

Developing Science Virtual Test to Measure Students’ Critical Thinking on Living Things and Environmental Sustainability Theme

NASA Astrophysics Data System (ADS)

Akbar, M. N.; Firman, H.; Rusyati, L.

2017-02-01

Critical thinking is skill and ability to use of risk taking creativity to make a decision and knowledge as a result, analysis and synthesis that, evaluation, to acquire, information search, to develop thinking, as an individual aware of his or her own thinking. The aim of this study is to develop the science virtual test to measure students’ critical thinking on living things and environmental sustainability theme. The research method that is used in this research was descriptive research. The development of science virtual test item consist of five steps: (1) content analysis; (2) constructing the instrument (multiple choice) based on the elements of critical thinking by Inch; (3) validity judgment of the instrument by the expert; (4) legibility test of the instrument; (5) conducting the large field test. On the large field test was gained the results of validity and reliability of the test, difficulty index, discriminating power, and quality of distractor. The subjects of research were 8th grade students at International Junior High School in Bandung with 125 total of respondents. The coefficient alpha (α) was 0.747, the reliability of the test was categorized as ‘high’ and value of RXY correlation was 0.63 which mean that the validity of the test was categorized as ‘high’. These means that science virtual test can be used to measure student’s critical thinking with a good consistency. It is expected for other researcher to take this description as one of the basic information to be considered in developing science virtual test for improving students’ critical thinking by various kind of topic.

Young adolescents' engagement in dietary behaviour - the impact of gender, socio-economic status, self-efficacy and scientific literacy. Methodological aspects of constructing measures in nutrition literacy research using the Rasch model.

PubMed

Guttersrud, Øystein; Petterson, Kjell Sverre

2015-10-01

The present study validates a revised scale measuring individuals' level of the 'engagement in dietary behaviour' aspect of 'critical nutrition literacy' and describes how background factors affect this aspect of Norwegian tenth-grade students' nutrition literacy. Data were gathered electronically during a field trial of a standardised sample test in science. Test items and questionnaire constructs were distributed evenly across four electronic field-test booklets. Data management and analysis were performed using the RUMM2030 item analysis package and the IBM SPSS Statistics 20 statistical software package. Students responded on computers at school. Seven hundred and forty tenth-grade students at twenty-seven randomly sampled public schools were enrolled in the field-test study. The engagement in dietary behaviour scale and the self-efficacy in science scale were distributed to 178 of these students. The dietary behaviour scale and the self-efficacy in science scale came out as valid, reliable and well-targeted instruments usable for the construction of measurements. Girls and students with high self-efficacy reported higher engagement in dietary behaviour than other students. Socio-economic status and scientific literacy - measured as ability in science by applying an achievement test - did not correlate significantly different from zero with students' engagement in dietary behaviour.

Spatiotemporal Data Organization and Application Research

NASA Astrophysics Data System (ADS)

Tan, C.; Yan, S.

2017-09-01

Organization and management of spatiotemporal data is a key support technology for intelligence in all fields of the smart city. The construction of a smart city cannot be realized without spatiotemporal data. Oriented to support intelligent applications this paper proposes an organizational model for spatiotemporal data, and details the construction of a spatiotemporal big data calculation, analysis, and service framework for highly efficient management and intelligent application of spatiotemporal data for the entire data life cycle.

An aerosol activation metamodel of v1.2.0 of the pyrcel cloud parcel model: development and offline assessment for use in an aerosol–climate model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rothenberg, Daniel; Wang, Chien

We describe an emulator of a detailed cloud parcel model which has been trained to assess droplet nucleation from a complex, multimodal aerosol size distribution simulated by a global aerosol–climate model. The emulator is constructed using a sensitivity analysis approach (polynomial chaos expansion) which reproduces the behavior of the targeted parcel model across the full range of aerosol properties and meteorology simulated by the parent climate model. An iterative technique using aerosol fields sampled from a global model is used to identify the critical aerosol size distribution parameters necessary for accurately predicting activation. Across the large parameter space used tomore » train them, the emulators estimate cloud droplet number concentration (CDNC) with a mean relative error of 9.2% for aerosol populations without giant cloud condensation nuclei (CCN) and 6.9% when including them. Versus a parcel model driven by those same aerosol fields, the best-performing emulator has a mean relative error of 4.6%, which is comparable with two commonly used activation schemes also evaluated here (which have mean relative errors of 2.9 and 6.7%, respectively). We identify the potential for regional biases in modeled CDNC, particularly in oceanic regimes, where our best-performing emulator tends to overpredict by 7%, whereas the reference activation schemes range in mean relative error from -3 to 7%. The emulators which include the effects of giant CCN are more accurate in continental regimes (mean relative error of 0.3%) but strongly overestimate CDNC in oceanic regimes by up to 22%, particularly in the Southern Ocean. Finally, the biases in CDNC resulting from the subjective choice of activation scheme could potentially influence the magnitude of the indirect effect diagnosed from the model incorporating it.« less

An aerosol activation metamodel of v1.2.0 of the pyrcel cloud parcel model: development and offline assessment for use in an aerosol–climate model

DOE PAGES

Rothenberg, Daniel; Wang, Chien

2017-04-27

We describe an emulator of a detailed cloud parcel model which has been trained to assess droplet nucleation from a complex, multimodal aerosol size distribution simulated by a global aerosol–climate model. The emulator is constructed using a sensitivity analysis approach (polynomial chaos expansion) which reproduces the behavior of the targeted parcel model across the full range of aerosol properties and meteorology simulated by the parent climate model. An iterative technique using aerosol fields sampled from a global model is used to identify the critical aerosol size distribution parameters necessary for accurately predicting activation. Across the large parameter space used tomore » train them, the emulators estimate cloud droplet number concentration (CDNC) with a mean relative error of 9.2% for aerosol populations without giant cloud condensation nuclei (CCN) and 6.9% when including them. Versus a parcel model driven by those same aerosol fields, the best-performing emulator has a mean relative error of 4.6%, which is comparable with two commonly used activation schemes also evaluated here (which have mean relative errors of 2.9 and 6.7%, respectively). We identify the potential for regional biases in modeled CDNC, particularly in oceanic regimes, where our best-performing emulator tends to overpredict by 7%, whereas the reference activation schemes range in mean relative error from -3 to 7%. The emulators which include the effects of giant CCN are more accurate in continental regimes (mean relative error of 0.3%) but strongly overestimate CDNC in oceanic regimes by up to 22%, particularly in the Southern Ocean. Finally, the biases in CDNC resulting from the subjective choice of activation scheme could potentially influence the magnitude of the indirect effect diagnosed from the model incorporating it.« less

Experiments with central-limit properties of spatial samples from locally covariant random fields

USGS Publications Warehouse

Barringer, T.H.; Smith, T.E.

1992-01-01

When spatial samples are statistically dependent, the classical estimator of sample-mean standard deviation is well known to be inconsistent. For locally dependent samples, however, consistent estimators of sample-mean standard deviation can be constructed. The present paper investigates the sampling properties of one such estimator, designated as the tau estimator of sample-mean standard deviation. In particular, the asymptotic normality properties of standardized sample means based on tau estimators are studied in terms of computer experiments with simulated sample-mean distributions. The effects of both sample size and dependency levels among samples are examined for various value of tau (denoting the size of the spatial kernel for the estimator). The results suggest that even for small degrees of spatial dependency, the tau estimator exhibits significantly stronger normality properties than does the classical estimator of standardized sample means. ?? 1992.

Analysis of Material Handling Safety in Construction Sites and Countermeasures for Effective Enhancement

PubMed Central

Anil Kumar, C. N.; Sakthivel, M.; Elangovan, R. K.; Arularasu, M.

2015-01-01

One of many hazardous workplaces includes the construction sites as they involve several dangerous tasks. Many studies have revealed that material handling equipment is a major cause of accidents at these sites. Though safety measures are being followed and monitored continuously, accident rates are still high as either workers are unaware of hazards or the safety regulations are not being strictly followed. This paper analyses the safety management systems at construction sites through means of questionnaire surveys with employees, specifically referring to safety of material handling equipment. Based on results of the questionnaire surveys, two construction sites were selected for a safety education program targeting worker safety related to material handling equipment. Knowledge levels of the workers were gathered before and after the program and results obtained were subjected to a t-test analysis to mark significance level of the conducted safety education program. PMID:26446572

Electrical stimulation systems for cardiac tissue engineering

PubMed Central

Tandon, Nina; Cannizzaro, Christopher; Chao, Pen-Hsiu Grace; Maidhof, Robert; Marsano, Anna; Au, Hoi Ting Heidi; Radisic, Milica; Vunjak-Novakovic, Gordana

2009-01-01

We describe a protocol for tissue engineering of synchronously contractile cardiac constructs by culturing cardiac cells with the application of pulsatile electrical fields designed to mimic those present in the native heart. Tissue culture is conducted in a customized chamber built to allow for cultivation of (i) engineered three-dimensional (3D) cardiac tissue constructs, (ii) cell monolayers on flat substrates or (iii) cells on patterned substrates. This also allows for analysis of the individual and interactive effects of pulsatile electrical field stimulation and substrate topography on cell differentiation and assembly. The protocol is designed to allow for delivery of predictable electrical field stimuli to cells, monitoring environmental parameters, and assessment of cell and tissue responses. The duration of the protocol is 5 d for two-dimensional cultures and 10 d for 3D cultures. PMID:19180087

Effectiveness of Automated Chinese Sentence Scoring with Latent Semantic Analysis

ERIC Educational Resources Information Center

Liao, Chen-Huei; Kuo, Bor-Chen; Pai, Kai-Chih

2012-01-01

Automated scoring by means of Latent Semantic Analysis (LSA) has been introduced lately to improve the traditional human scoring system. The purposes of the present study were to develop a LSA-based assessment system to evaluate children's Chinese sentence construction skills and to examine the effectiveness of LSA-based automated scoring function…

A Proposal for Phase 4 of the Forest Inventory and Analysis Program

Treesearch

Ronald E. McRoberts

2005-01-01

Maps of forest cover were constructed using observations from forest inventory plots, Landsat Thematic Mapper satellite imagery, and a logistic regression model. Estimates of mean proportion forest area and the variance of the mean were calculated for circular study areas with radii ranging from 1 km to 15 km. The spatial correlation among pixel predictions was...

Effectiveness of a constructed wetland for treating alkaline bauxite residue leachate: a 1-year field study.

PubMed

Higgins, Derek; Curtin, Teresa; Courtney, Ronan

2017-03-01

Increasing volumes of bauxite residues and their associated leachates represent a significant environmental challenge to the alumina industry. Constructed wetlands have been proposed as a potential approach for leachate treatment, but there is limited data on field-scale applications. The research presented here provides preliminary evaluation of a purpose-built constructed wetland to buffer leachate from a bauxite residue disposal site in Ireland. Data collected over a 1-year period demonstrated that the pH of bauxite residue leachates could be effectively reduced from ca. pH 10.3 to 8.1 but was influenced by influent variability and temporal changes. The wetland was also effective in decreasing elemental loading, and sequential extractions suggested that the bulk of the sediment-bound metal inventory was in hard-to-leach phases. Elemental analysis of Phragmites australis showed that although vegetation displayed seasonal variation, no trace elements were at concentrations of concern.

Globalisation, transnational policies and adult education

NASA Astrophysics Data System (ADS)

Milana, Marcella

2012-12-01

Globalisation, transnational policies and adult education - This paper examines policy documents produced by the United Nations Educational, Scientific and Cultural Organization (UNESCO) and the European Union (EU) in the field of adult education and learning. Both these entities address adult education as an explicit object of policy. This paper investigates how globalisation processes are constructed as policy problems when these transnational political agents propose adult education as a response. The author's main argument is that while UNESCO presents the provision of adult education as a means for governments worldwide to overcome disadvantages experienced by their own citizenry, the EU institutionalises learning experiences as a means for governments to sustain regional economic growth and political expansion. After reviewing the literature on globalisation to elucidate the theories that inform current understanding of contemporary economic, political, cultural and ecological changes as political problems, she presents the conceptual and methodological framework of her analysis. The author then examines the active role played by UNESCO and the EU in promoting adult education as a policy objective at transnational level, and unpacks the specific problem "representations" that are substantiated by these organisations. She argues that UNESCO and EU processes assign specific values and meanings to globalisation, and that these reflect a limited understanding of the complexity of globalisation. Finally, she considers two of the effects produced by these problem representations.

Assessing the sustainable construction of large construction companies in Malaysia

NASA Astrophysics Data System (ADS)

Adewale, Bamgbade Jibril; Mohammed, Kamaruddeen Ahmed; Nasrun, Mohd Nawi Mohd

2016-08-01

Considering the increasing concerns for the consideration of sustainability issues in construction project delivery within the construction industry, this paper assesses the extent of sustainable construction among Malaysian large contractors, in order to ascertain the level of the industry's impacts on both the environment and the society. Sustainable construction explains the construction industry's responsibility to efficiently utilise the finite resources while also reducing construction impacts on both humans and the environment throughout the phases of construction. This study used proportionate stratified random sampling to conduct a field study with a sample of 172 contractors out of the 708 administered questionnaires. Data were collected from large contractors in the eleven states of peninsular Malaysia. Using the five-level rating scale (which include: 1= Very Low; 2= Low; 3= Moderate; 4= High; 5= Very High) to describe the level of sustainable construction of Malaysian contractors based on previous studies, statistical analysis reveals that environmental, social and economic sustainability of Malaysian large contractors are high.

Phased-array laser radar: Concept and application

NASA Technical Reports Server (NTRS)

Kadrmas, K. A.

1973-01-01

The design and construction of a coaxial transmitter-receiver combination was investigated. Major emphasis was placed on simple permanent optical alignment, transmitter-receiver field of view matching, use of a pulsed gas laser as a transmitter maximum optical efficiency, complete digital control of data acquisition, and optical mount pointing and tracking. Also a means of expanding the coaxial transmitter-receiver concept to allow phased-array lidar, par-lidar was described.

Why the Major Field Test in Business Does Not Report Subscores: Reliability and Construct Validity Evidence. Research Report. ETS RR-12-11

ERIC Educational Resources Information Center

Ling, Guangming

2012-01-01

To assess the value of individual students' subscores on the Major Field Test in Business (MFT Business), I examined the test's internal structure with factor analysis and structural equation model methods, and analyzed the subscore reliabilities using the augmented scores method. Analyses of the internal structure suggested that the MFT Business…

Dielectric properties of 3D-printed materials for anatomy specific 3D-printed MRI coils

NASA Astrophysics Data System (ADS)

Behzadnezhad, Bahareh; Collick, Bruce D.; Behdad, Nader; McMillan, Alan B.

2018-04-01

Additive manufacturing provides a low-cost and rapid means to translate 3D designs into the construction of a prototype. For MRI, this type of manufacturing can be used to construct various components including the structure of RF coils. In this paper, we characterize the material properties (dielectric constant and loss tangent) of several common 3D-printed polymers in the MRI frequency range of 63-300 MHz (for MRI magnetic field strengths of 1.5-7 T), and utilize these material properties in full-wave electromagnetic simulations to design and construct a very low-cost subject/anatomy-specific 3D-printed receive-only RF coil that fits close to the body. We show that the anatomy-specific coil exhibits higher signal-to-noise ratio compared to a conventional flat surface coil.

Cognitive/Information Processing Psychology and Instruction: Reviewing Recent Theory and Practice.

ERIC Educational Resources Information Center

Gallagher, John P.

1979-01-01

Discusses recent developments in instructional psychology relative to cognitive task analysis, individual difference variables, and cognitive models of interactive instructional decision making, which use constructs developed within the field of cognitive/information processing psychology. (Author/WBC)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rabiti, Cristian; Alfonsi, Andrea; Huang, Dongli

This report collect the effort performed to improve the reliability analysis capabilities of the RAVEN code and explore new opportunity in the usage of surrogate model by extending the current RAVEN capabilities to multi physics surrogate models and construction of surrogate models for high dimensionality fields.

Integral abutment bridges under thermal loading : field monitoring and analysis.

DOT National Transportation Integrated Search

2017-08-01

Integral abutment bridges (IABs) have gained popularity throughout the United States due to their low construction and maintenance costs. Previous research on IABs has been heavily focused on substructure performance, leaving a need for better unders...

Linear dynamical modes as new variables for data-driven ENSO forecast

NASA Astrophysics Data System (ADS)

Gavrilov, Andrey; Seleznev, Aleksei; Mukhin, Dmitry; Loskutov, Evgeny; Feigin, Alexander; Kurths, Juergen

2018-05-01

A new data-driven model for analysis and prediction of spatially distributed time series is proposed. The model is based on a linear dynamical mode (LDM) decomposition of the observed data which is derived from a recently developed nonlinear dimensionality reduction approach. The key point of this approach is its ability to take into account simple dynamical properties of the observed system by means of revealing the system's dominant time scales. The LDMs are used as new variables for empirical construction of a nonlinear stochastic evolution operator. The method is applied to the sea surface temperature anomaly field in the tropical belt where the El Nino Southern Oscillation (ENSO) is the main mode of variability. The advantage of LDMs versus traditionally used empirical orthogonal function decomposition is demonstrated for this data. Specifically, it is shown that the new model has a competitive ENSO forecast skill in comparison with the other existing ENSO models.

On the Utilization of Social Animals as a Model for Social Robotics

PubMed Central

Miklósi, Ádám; Gácsi, Márta

2012-01-01

Social robotics is a thriving field in building artificial agents. The possibility to construct agents that can engage in meaningful social interaction with humans presents new challenges for engineers. In general, social robotics has been inspired primarily by psychologists with the aim of building human-like robots. Only a small subcategory of “companion robots” (also referred to as robotic pets) was built to mimic animals. In this opinion essay we argue that all social robots should be seen as companions and more conceptual emphasis should be put on the inter-specific interaction between humans and social robots. This view is underlined by the means of an ethological analysis and critical evaluation of present day companion robots. We suggest that human–animal interaction provides a rich source of knowledge for designing social robots that are able to interact with humans under a wide range of conditions. PMID:22457658

Electrochemical Analysis of Conducting Polymer Thin Films

PubMed Central

Vyas, Ritesh N.; Wang, Bin

2010-01-01

Polyelectrolyte multilayers built via the layer-by-layer (LbL) method has been one of the most promising systems in the field of materials science. Layered structures can be constructed by the adsorption of various polyelectrolyte species onto the surface of a solid or liquid material by means of electrostatic interaction. The thickness of the adsorbed layers can be tuned precisely in the nanometer range. Stable, semiconducting thin films are interesting research subjects. We use a conducting polymer, poly(p-phenylene vinylene) (PPV), in the preparation of a stable thin film via the LbL method. Cyclic voltammetry and electrochemical impedance spectroscopy have been used to characterize the ionic conductivity of the PPV multilayer films. The ionic conductivity of the films has been found to be dependent on the polymerization temperature. The film conductivity can be fitted to a modified Randle’s circuit. The circuit equivalent calculations are performed to provide the diffusion coefficient values. PMID:20480052

Investigations of Relatively Easy To Construct Antennas With Efficiency in Receiving Schumann Resonances: Preparations for a Miniaturized Reconfigurable ELF Receiver

NASA Technical Reports Server (NTRS)

Farmer, Brian W.; Hannan, Robert C.

2003-01-01

Relatively little is known about the cavity between the Earth and the ionosphere, which opens opportunities for technological advances and unique ideas. One effective means to study this cavity is with extremely low frequency (ELF) antennas. Possible applications of these antennas are global weather prediction, earthquake prediction, planetary exploration, communication, wireless transmission of power, or even a free energy source. The superconducting quantum interference device SQUID) and the coil antenna are the two most acceptable receivers discovered for picking up ELF magnetic fields. Both antennas have the potential for size reduction, allowing them to be portable enough for access to space and even for personal ware. With improvements of these antennas and signal processing, insightful analysis of Schumann resonance (SR) can give the science community a band of radio frequency (RF) signals for improving life here on Earth and exploring beyond.

Implications of ICD-10 for Sarcopenia Clinical Practice and Clinical Trials: Report by the International Conference on Frailty and Sarcopenia Research Task Force.

PubMed

Vellas, B; Fielding, R A; Bens, C; Bernabei, R; Cawthon, P M; Cederholm, T; Cruz-Jentoft, A J; Del Signore, S; Donahue, S; Morley, J; Pahor, M; Reginster, J-Y; Rodriguez Mañas, L; Rolland, Y; Roubenoff, R; Sinclair, A; Cesari, M

2018-01-01

Establishment of an ICD-10-CM code for sarcopenia in 2016 was an important step towards reaching international consensus on the need for a nosological framework of age-related skeletal muscle decline. The International Conference on Frailty and Sarcopenia Research Task Force met in April 2017 to discuss the meaning, significance, and barriers to the implementation of the new code as well as strategies to accelerate development of new therapies. Analyses by the Sarcopenia Definitions and Outcomes Consortium are underway to develop quantitative definitions of sarcopenia. A consensus conference is planned to evaluate this analysis. The Task Force also discussed lessons learned from sarcopenia trials that could be applied to future trials, as well as lessons from the osteoporosis field, a clinical condition with many constructs similar to sarcopenia and for which ad hoc treatments have been developed and approved by regulatory agencies.

Use of safety management practices for improving project performance.

PubMed

Cheng, Eddie W L; Kelly, Stephen; Ryan, Neal

2015-01-01

Although site safety has long been a key research topic in the construction field, there is a lack of literature studying safety management practices (SMPs). The current research, therefore, aims to test the effect of SMPs on project performance. An empirical study was conducted in Hong Kong and the data collected were analysed with multiple regression analysis. Results suggest that 3 of the 15 SMPs, which were 'safety committee at project/site level', 'written safety policy', and 'safety training scheme' explained the variance in project performance significantly. Discussion about the impact of these three SMPs on construction was provided. Assuring safe construction should be an integral part of a construction project plan.

Large-scale compensation of errors in pairwise-additive empirical force fields: comparison of AMBER intermolecular terms with rigorous DFT-SAPT calculations.

PubMed

Zgarbová, Marie; Otyepka, Michal; Sponer, Jirí; Hobza, Pavel; Jurecka, Petr

2010-09-21

The intermolecular interaction energy components for several molecular complexes were calculated using force fields available in the AMBER suite of programs and compared with Density Functional Theory-Symmetry Adapted Perturbation Theory (DFT-SAPT) values. The extent to which such comparison is meaningful is discussed. The comparability is shown to depend strongly on the intermolecular distance, which means that comparisons made at one distance only are of limited value. At large distances the coulombic and van der Waals 1/r(6) empirical terms correspond fairly well with the DFT-SAPT electrostatics and dispersion terms, respectively. At the onset of electronic overlap the empirical values deviate from the reference values considerably. However, the errors in the force fields tend to cancel out in a systematic manner at equilibrium distances. Thus, the overall performance of the force fields displays errors an order of magnitude smaller than those of the individual interaction energy components. The repulsive 1/r(12) component of the van der Waals expression seems to be responsible for a significant part of the deviation of the force field results from the reference values. We suggest that further improvement of the force fields for intermolecular interactions would require replacement of the nonphysical 1/r(12) term by an exponential function. Dispersion anisotropy and its effects are discussed. Our analysis is intended to show that although comparing the empirical and non-empirical interaction energy components is in general problematic, it might bring insights useful for the construction of new force fields. Our results are relevant to often performed force-field-based interaction energy decompositions.

High‐resolution trench photomosaics from image‐based modeling: Workflow and error analysis

USGS Publications Warehouse

Reitman, Nadine G.; Bennett, Scott E. K.; Gold, Ryan D.; Briggs, Richard; Duross, Christopher

2015-01-01

Photomosaics are commonly used to construct maps of paleoseismic trench exposures, but the conventional process of manually using image‐editing software is time consuming and produces undesirable artifacts and distortions. Herein, we document and evaluate the application of image‐based modeling (IBM) for creating photomosaics and 3D models of paleoseismic trench exposures, illustrated with a case‐study trench across the Wasatch fault in Alpine, Utah. Our results include a structure‐from‐motion workflow for the semiautomated creation of seamless, high‐resolution photomosaics designed for rapid implementation in a field setting. Compared with conventional manual methods, the IBM photomosaic method provides a more accurate, continuous, and detailed record of paleoseismic trench exposures in approximately half the processing time and 15%–20% of the user input time. Our error analysis quantifies the effect of the number and spatial distribution of control points on model accuracy. For this case study, an ∼87  m2 exposure of a benched trench photographed at viewing distances of 1.5–7 m yields a model with <2  cm root mean square error (rmse) with as few as six control points. Rmse decreases as more control points are implemented, but the gains in accuracy are minimal beyond 12 control points. Spreading control points throughout the target area helps to minimize error. We propose that 3D digital models and corresponding photomosaics should be standard practice in paleoseismic exposure archiving. The error analysis serves as a guide for future investigations that seek balance between speed and accuracy during photomosaic and 3D model construction.

A theoretical/experimental program to develop active optical pollution sensors

NASA Technical Reports Server (NTRS)

Mills, F. S.; Blais, R. N.; Kindle, E. C.

1977-01-01

Light detection and ranging (LIDAR) technology was applied to the assessment of air quality, and its usefulness was evaluated by actual field tests. Necessary hardware was successfully constructed and operated in the field. Measurements of necessary physical parameters, such as SO2 absorption coefficients were successfully completed and theoretical predictions of differential absorption performance were reported. Plume modeling improvements were proposed. A full scale field test of equipment, data analysis and auxiliary data support was conducted in Maryland during September 1976.

Mean-field velocity difference model considering the average effect of multi-vehicle interaction

NASA Astrophysics Data System (ADS)

Guo, Yan; Xue, Yu; Shi, Yin; Wei, Fang-ping; Lü, Liang-zhong; He, Hong-di

2018-06-01

In this paper, a mean-field velocity difference model(MFVD) is proposed to describe the average effect of multi-vehicle interactions on the whole road. By stability analysis, the stability condition of traffic system is obtained. Comparison with stability of full velocity-difference (FVD) model and the completeness of MFVD model are discussed. The mKdV equation is derived from MFVD model through nonlinear analysis to reveal the traffic jams in the form of the kink-antikink density wave. Then the numerical simulation is performed and the results illustrate that the average effect of multi-vehicle interactions plays an important role in effectively suppressing traffic jam. The increase strength of the mean-field velocity difference in MFVD model can rapidly reduce traffic jam and enhance the stability of traffic system.

The NASA Inductrack Model Rocket Launcher at the Lawrence Livermore National Laboratory

NASA Technical Reports Server (NTRS)

Tung, L. S.; Post, R. F.; Cook, E.; Martinez-Frias, J.

2000-01-01

The Inductrack magnetic levitation system, developed at the Lawrence Livermore National Laboratory, is being studied for its possible use for launching rockets. Under NASA sponsorship, a small model system is being constructed at the Laboratory to pursue key technical aspects of this proposed application. The Inductrack is a passive magnetic levitation system employing special arrays of high-field permanent magnets (Halbach arrays) on the levitating carrier, moving above a "track" consisting of a close-packed array of shorted coils with which are interleaved with special drive coils. Halbach arrays produce a strong spatially periodic magnetic field on the front surface of the arrays, while canceling the field on their back surface. Relative motion between the Halbach arrays and the track coils induces currents in those coils. These currents levitate the carrier cart by interacting with the horizontal component of the magnetic field. Pulsed currents in the drive coils, synchronized with the motion of the carrier, interact with the vertical component of the magnetic field to provide acceleration forces. Motional stability, including resistance to both vertical and lateral aerodynamic forces, is provided by having Halbach arrays that interact with both the upper and the lower sides of the track coils. In its completed form the model system that is under construction will have a track approximately 100 meters in length along which the carrier cart will be propelled up to peak speeds of Mach 0.4 to 0.5 before being decelerated. Preliminary studies of the parameters of a full-scale system have also been made. These studies address the problems of scale-up, including means to simplify the track construction and to reduce the cost of the pulsed-power systems needed for propulsion.

An Analysis of Construction Contractor Performance Evaluation System

DTIC Science & Technology

2009-03-01

65 8. Summary of Determinant and KMO Values for Finalized...principle component analysis output is the KMO and Bartlett‘s Test. KMO or Kaiser-Meyer-Olkin measure of sampling adequacy is used to identify if a...set of variables, when factored together, yield distinct and reliable factors (Field, 2005). KMO statistics vary between values of 0 to 1. Kaiser

Photomat: A Mobile Tool for Aiding in Student Construction of Research Questions and Data Analysis

ERIC Educational Resources Information Center

Shelley, Tia Renee; Dasgupta, Chandan; Silva, Alexandra; Lyons, Leilah; Moher, Tom

2015-01-01

This paper presents a new mobile software tool, PhotoMAT (Photo Management and Analysis Tool), and students' experiences with this tool within a scaffolded curricular unit--Neighborhood Safari. PhotoMAT was designed to support learners' investigations of backyard animal behavior and works with image sets obtained using fixed-position field cameras…

Statistical modeling of crystalline silica exposure by trade in the construction industry using a database compiled from the literature.

PubMed

Sauvé, Jean-François; Beaudry, Charles; Bégin, Denis; Dion, Chantal; Gérin, Michel; Lavoué, Jérôme

2012-09-01

A quantitative determinants-of-exposure analysis of respirable crystalline silica (RCS) levels in the construction industry was performed using a database compiled from an extensive literature review. Statistical models were developed to predict work-shift exposure levels by trade. Monte Carlo simulation was used to recreate exposures derived from summarized measurements which were combined with single measurements for analysis. Modeling was performed using Tobit models within a multimodel inference framework, with year, sampling duration, type of environment, project purpose, project type, sampling strategy and use of exposure controls as potential predictors. 1346 RCS measurements were included in the analysis, of which 318 were non-detects and 228 were simulated from summary statistics. The model containing all the variables explained 22% of total variability. Apart from trade, sampling duration, year and strategy were the most influential predictors of RCS levels. The use of exposure controls was associated with an average decrease of 19% in exposure levels compared to none, and increased concentrations were found for industrial, demolition and renovation projects. Predicted geometric means for year 1999 were the highest for drilling rig operators (0.238 mg m(-3)) and tunnel construction workers (0.224 mg m(-3)), while the estimated exceedance fraction of the ACGIH TLV by trade ranged from 47% to 91%. The predicted geometric means in this study indicated important overexposure compared to the TLV. However, the low proportion of variability explained by the models suggests that the construction trade is only a moderate predictor of work-shift exposure levels. The impact of the different tasks performed during a work shift should also be assessed to provide better management and control of RCS exposure levels on construction sites.

Measuring Alexithymia via Trait Approach-I: A Alexithymia Scale Item Selection and Formation of Factor Structure

PubMed Central

TATAR, Arkun; SALTUKOĞLU, Gaye; ALİOĞLU, Seda; ÇİMEN, Sümeyye; GÜVEN, Hülya; AY, Çağla Ebru

2017-01-01

Introduction It is not clear in the literature whether available instruments are sufficient to measure alexithymia because of its theoretical structure. Moreover, it has been reported that several measuring instruments are needed to measure this construct, and all the instruments have different error sources. The old and the new forms of Toronto Alexithymia Scale are the only instruments available in Turkish. Thus, the purpose of this study was to develop a new scale to measure alexithymia, selecting items and constructing the factor structure. Methods A total of 1117 patients aged from 19 to 82 years (mean = 35.05 years) were included. A 100-item pool was prepared and applied to 628 women and 489 men. Data were analyzed using Explanatory Factor Analysis, Confirmatory Factor Analysis, and Item Response Theory and 28 items were selected. The new form of 28 items was applied to 415 university students, including 271 women and 144 men aged from 18 to 30 (mean=21.44). Results The results of Explanatory Factor Analysis revealed a five-factor construct of “Solving and Expressing Affective Experiences,” “External Locused Cognitive Style,” “Tendency to Somatize Affections,” “Imaginary Life and Visualization,” and “Acting Impulsively,” along with a two-factor construct representing the “Affective” and “Cognitive” components. All the components of the construct showed good model fit and high internal consistency. The new form was tested in terms of internal consistency, test-retest reliability, and concurrent validity using Toronto Alexithymia Scale as criteria and discriminative validity using Five-Factor Personality Inventory Short Form. Conclusion The results showed that the new scale met the basic psychometric requirements. Results have been discussed in line with related studies. PMID:29033633

Validation of Interannual Differences of AIRS Monthly Mean Parameters

NASA Technical Reports Server (NTRS)

Susskind, Joel; Iredell, Lena; Keita, Fricky; Molnar, Gyula

2005-01-01

Monthly mean fields of select geophysical parameters derived from analysis of AIRS/AMSU data, and their interannual differences, are shown and compared with analogous fields derived from other sources. All AIRS fields are derived using the AIRS Science Team Version 4 algorithm. Monthly mean results are shown for January 2004, as are interannual differences between January 2004 and January 2003. AIRS temperature and water vapor profile fields are compared with monthly mean collocated ECMWF 3 hour forecast and monthly mean TOVS Pathfinder Path A data. AIRS Tropospheric and Stratospheric coarse climate indicators are compared with analogous MSU products derived by Spencer and christy and found in the TOVS Pathfinder Path A data set. Total ozone is compared with results produced by TOMS. OLR is compared with OLR derived using CERES data and found in the TOVS Pathfinder Path A data set. AIRS results agree well in all cases, especially in the interannual difference sense.

EXTENDING THE REALM OF OPTIMIZATION FOR COMPLEX SYSTEMS: UNCERTAINTY, COMPETITION, AND DYNAMICS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shanbhag, Uday V; Basar, Tamer; Meyn, Sean

Research reported addressed these topics: the development of analytical and algorithmic tools for distributed computation of Nash equilibria; synchronization in mean-field oscillator games, with an emphasis on learning and efficiency analysis; questions that combine learning and computation; questions including stochastic and mean-field games; modeling and control in the context of power markets.

Brazilian cross-cultural adaptation and validation of the List of Threatening Events Questionnaire (LTE-Q).

PubMed

Abreu, Patrícia B de; Cogo-Moreira, Hugo; Pose, Regina A; Laranjeira, Ronaldo; Caetano, Raul; Gaya, Carolina M; Madruga, Clarice S

2017-01-01

To perform a construct validation of the List of Threatening Events Questionnaire (LTE-Q), as well as convergence validation by identifying its association with drug use in a sample of the Brazilian population. This is a secondary analysis of the Second Brazilian National Alcohol and Drugs Survey (II BNADS), which used a cross-cultural adaptation of the LTE-Q in a probabilistic sample of 4,607 participants aged 14 years and older. Latent class analysis was used to validate the latent trait adversity (which considered the number of events from the list of 12 item in the LTE experienced by the respondent in the previous year) and logistic regression was performed to find its association with binge drinking and cocaine use. The confirmatory factor analysis returned a chi-square of 108.341, weighted root mean square residual (WRMR) of 1.240, confirmatory fit indices (CFI) of 0.970, Tucker-Lewis index (TLI) of 0.962, and root mean square error approximation (RMSEA) score of 1.000. LTE-Q convergence validation showed that the adversity latent trait increased the chances of binge drinking by 1.31 time and doubled the chances of previous year cocaine use (adjusted by sociodemographic variables). The use of the LTE-Q in Brazil should be encouraged in different research fields, including large epidemiological surveys, as it is also appropriate when time and budget are limited. The LTE-Q can be a useful tool in the development of targeted and more efficient prevention strategies.

Psychometric Properties of the Heart Disease Knowledge Scale: Evidence from Item and Confirmatory Factor Analyses

PubMed Central

Lim, Bee Chiu; Kueh, Yee Cheng; Arifin, Wan Nor; Ng, Kok Huan

2016-01-01

Background Heart disease knowledge is an important concept for health education, yet there is lack of evidence on proper validated instruments used to measure levels of heart disease knowledge in the Malaysian context. Methods A cross-sectional, survey design was conducted to examine the psychometric properties of the adapted English version of the Heart Disease Knowledge Questionnaire (HDKQ). Using proportionate cluster sampling, 788 undergraduate students at Universiti Sains Malaysia, Malaysia, were recruited and completed the HDKQ. Item analysis and confirmatory factor analysis (CFA) were used for the psychometric evaluation. Construct validity of the measurement model was included. Results Most of the students were Malay (48%), female (71%), and from the field of science (51%). An acceptable range was obtained with respect to both the difficulty and discrimination indices in the item analysis results. The difficulty index ranged from 0.12–0.91 and a discrimination index of ≥ 0.20 were reported for the final retained 23 items. The final CFA model showed an adequate fit to the data, yielding a 23-item, one-factor model [weighted least squares mean and variance adjusted scaled chi-square difference = 1.22, degrees of freedom = 2, P-value = 0.544, the root mean square error of approximation = 0.03 (90% confidence interval = 0.03, 0.04); close-fit P-value = > 0.950]. Conclusion Adequate psychometric values were obtained for Malaysian undergraduate university students using the 23-item, one-factor model of the adapted HDKQ. PMID:27660543

Psychometric Properties of the Heart Disease Knowledge Scale: Evidence from Item and Confirmatory Factor Analyses.

PubMed

Lim, Bee Chiu; Kueh, Yee Cheng; Arifin, Wan Nor; Ng, Kok Huan

2016-07-01

Heart disease knowledge is an important concept for health education, yet there is lack of evidence on proper validated instruments used to measure levels of heart disease knowledge in the Malaysian context. A cross-sectional, survey design was conducted to examine the psychometric properties of the adapted English version of the Heart Disease Knowledge Questionnaire (HDKQ). Using proportionate cluster sampling, 788 undergraduate students at Universiti Sains Malaysia, Malaysia, were recruited and completed the HDKQ. Item analysis and confirmatory factor analysis (CFA) were used for the psychometric evaluation. Construct validity of the measurement model was included. Most of the students were Malay (48%), female (71%), and from the field of science (51%). An acceptable range was obtained with respect to both the difficulty and discrimination indices in the item analysis results. The difficulty index ranged from 0.12-0.91 and a discrimination index of ≥ 0.20 were reported for the final retained 23 items. The final CFA model showed an adequate fit to the data, yielding a 23-item, one-factor model [weighted least squares mean and variance adjusted scaled chi-square difference = 1.22, degrees of freedom = 2, P-value = 0.544, the root mean square error of approximation = 0.03 (90% confidence interval = 0.03, 0.04); close-fit P-value = > 0.950]. Adequate psychometric values were obtained for Malaysian undergraduate university students using the 23-item, one-factor model of the adapted HDKQ.

Forecasting transitions in systems with high-dimensional stochastic complex dynamics: a linear stability analysis of the tangled nature model.

PubMed

Cairoli, Andrea; Piovani, Duccio; Jensen, Henrik Jeldtoft

2014-12-31

We propose a new procedure to monitor and forecast the onset of transitions in high-dimensional complex systems. We describe our procedure by an application to the tangled nature model of evolutionary ecology. The quasistable configurations of the full stochastic dynamics are taken as input for a stability analysis by means of the deterministic mean-field equations. Numerical analysis of the high-dimensional stability matrix allows us to identify unstable directions associated with eigenvalues with a positive real part. The overlap of the instantaneous configuration vector of the full stochastic system with the eigenvectors of the unstable directions of the deterministic mean-field approximation is found to be a good early warning of the transitions occurring intermittently.

Chain architecture and micellization: A mean-field coarse-grained model for poly(ethylene oxide) alkyl ether surfactants

DOE Office of Scientific and Technical Information (OSTI.GOV)

García Daza, Fabián A.; Mackie, Allan D., E-mail: allan.mackie@urv.cat; Colville, Alexander J.

2015-03-21

Microscopic modeling of surfactant systems is expected to be an important tool to describe, understand, and take full advantage of the micellization process for different molecular architectures. Here, we implement a single chain mean field theory to study the relevant equilibrium properties such as the critical micelle concentration (CMC) and aggregation number for three sets of surfactants with different geometries maintaining constant the number of hydrophobic and hydrophilic monomers. The results demonstrate the direct effect of the block organization for the surfactants under study by means of an analysis of the excess energy and entropy which can be accurately determinedmore » from the mean-field scheme. Our analysis reveals that the CMC values are sensitive to branching in the hydrophilic head part of the surfactant and can be observed in the entropy-enthalpy balance, while aggregation numbers are also affected by splitting the hydrophobic tail of the surfactant and are manifested by slight changes in the packing entropy.« less

Chain architecture and micellization: A mean-field coarse-grained model for poly(ethylene oxide) alkyl ether surfactants

NASA Astrophysics Data System (ADS)

García Daza, Fabián A.; Colville, Alexander J.; Mackie, Allan D.

2015-03-01

Microscopic modeling of surfactant systems is expected to be an important tool to describe, understand, and take full advantage of the micellization process for different molecular architectures. Here, we implement a single chain mean field theory to study the relevant equilibrium properties such as the critical micelle concentration (CMC) and aggregation number for three sets of surfactants with different geometries maintaining constant the number of hydrophobic and hydrophilic monomers. The results demonstrate the direct effect of the block organization for the surfactants under study by means of an analysis of the excess energy and entropy which can be accurately determined from the mean-field scheme. Our analysis reveals that the CMC values are sensitive to branching in the hydrophilic head part of the surfactant and can be observed in the entropy-enthalpy balance, while aggregation numbers are also affected by splitting the hydrophobic tail of the surfactant and are manifested by slight changes in the packing entropy.

A two-step along-track spectral analysis for estimating the magnetic signals of magnetospheric ring current from Swarm data

NASA Astrophysics Data System (ADS)

Martinec, Zdeněk; Velímský, Jakub; Haagmans, Roger; Šachl, Libor

2018-02-01

This study deals with the analysis of Swarm vector magnetic field measurements in order to estimate the magnetic field of magnetospheric ring current. For a single Swarm satellite, the magnetic measurements are processed by along-track spectral analysis on a track-by-track basis. The main and lithospheric magnetic fields are modelled by the CHAOS-6 field model and subtracted from the along-track Swarm magnetic data. The mid-latitude residual signal is then spectrally analysed and extrapolated to the polar regions. The resulting model of the magnetosphere (model MME) is compared to the existing Swarm Level 2 magnetospheric field model (MMA_SHA_2C). The differences of up to 10 nT are found on the nightsides Swarm data from 2014 April 8 to May 10, which are due to different processing schemes used to construct the two magnetospheric magnetic field models. The forward-simulated magnetospheric magnetic field generated by the external part of model MME then demonstrates the consistency of the separation of the Swarm along-track signal into the external and internal parts by the two-step along-track spectral analysis.

Influence of the Time Scale on the Construction of Financial Networks

PubMed Central

Emmert-Streib, Frank; Dehmer, Matthias

2010-01-01

Background In this paper we investigate the definition and formation of financial networks. Specifically, we study the influence of the time scale on their construction. Methodology/Principal Findings For our analysis we use correlation-based networks obtained from the daily closing prices of stock market data. More precisely, we use the stocks that currently comprise the Dow Jones Industrial Average (DJIA) and estimate financial networks where nodes correspond to stocks and edges correspond to none vanishing correlation coefficients. That means only if a correlation coefficient is statistically significant different from zero, we include an edge in the network. This construction procedure results in unweighted, undirected networks. By separating the time series of stock prices in non-overlapping intervals, we obtain one network per interval. The length of these intervals corresponds to the time scale of the data, whose influence on the construction of the networks will be studied in this paper. Conclusions/Significance Numerical analysis of four different measures in dependence on the time scale for the construction of networks allows us to gain insights about the intrinsic time scale of the stock market with respect to a meaningful graph-theoretical analysis. PMID:20949124

Cartan symmetries and global dynamical systems analysis in a higher-order modified teleparallel theory

NASA Astrophysics Data System (ADS)

Karpathopoulos, L.; Basilakos, S.; Leon, G.; Paliathanasis, A.; Tsamparlis, M.

2018-07-01

In a higher-order modified teleparallel theory cosmological we present analytical cosmological solutions. In particular we determine forms of the unknown potential which drives the scalar field such that the field equations form a Liouville integrable system. For the determination of the conservation laws we apply the Cartan symmetries. Furthermore, inspired from our solutions, a toy model is studied and it is shown that it can describe the Supernova data, while at the same time introduces dark matter components in the Hubble function. When the extra matter source is a stiff fluid then we show how analytical solutions for Bianchi I universes can be constructed from our analysis. Finally, we perform a global dynamical analysis of the field equations by using variables different from that of the Hubble-normalization.

Barriers of lean construction implementation in the Moroccan construction industry

NASA Astrophysics Data System (ADS)

Bajjou, Mohamed Saad; Chafi, Anas

2018-04-01

Improving the production system performance has become a fundamental pillar that must be taken into consideration in the construction industry. Recent developments in the construction sector have led to renewed interest in new techniques of management. Lean Construction is a very effective approach that has gained a high popularity by its ability to eliminate waste and maximize the value for the customer. Although both developed and developing countries have gained large benefits by implementing Lean Construction approach, several experiences showed many barriers that are hindering its implementation especially in developing countries. This paper aims to assess the critical barriers to the successful implementation in the Moroccan construction industry. Based on a literature review, followed by an analysis of data collected from a questionnaire survey which targeted 330 practitioners in the Moroccan construction field, several barriers were identified as key barriers. The findings of this investigation revealed that there are significant barriers such as Lack of knowledge about Lean Construction concepts, Unskilled Human Resources, and insufficient financial resources.

The methodological quality of diagnostic test accuracy studies for musculoskeletal conditions can be improved.

PubMed

Henschke, Nicholas; Keuerleber, Julia; Ferreira, Manuela; Maher, Christopher G; Verhagen, Arianne P

2014-04-01

To provide an overview of reporting and methodological quality in diagnostic test accuracy (DTA) studies in the musculoskeletal field and evaluate the use of the QUality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist. A literature review identified all systematic reviews that evaluated the accuracy of clinical tests to diagnose musculoskeletal conditions and used the QUADAS checklist. Two authors screened all identified reviews and extracted data on the target condition, index tests, reference standard, included studies, and QUADAS items. A descriptive analysis of the QUADAS checklist was performed, along with Rasch analysis to examine the construct validity and internal reliability. A total of 19 systematic reviews were included, which provided data on individual items of the QUADAS checklist for 392 DTA studies. In the musculoskeletal field, uninterpretable or intermediate test results are commonly not reported, with 175 (45%) studies scoring "no" to this item. The proportion of studies fulfilling certain items varied from 22% (item 11) to 91% (item 3). The interrater reliability of the QUADAS checklist was good and Rasch analysis showed excellent construct validity and internal consistency. This overview identified areas where the reporting and performance of diagnostic studies within the musculoskeletal field can be improved. Copyright © 2014 Elsevier Inc. All rights reserved.

Non-price competition in the regional high-rise construction market

NASA Astrophysics Data System (ADS)

Ganebnykh, Elena; Burtseva, Tatyana; Gurova, Ekaterina; Polyakova, Irina

2018-03-01

The article analyzes the market of high-rise residential construction in the city of Kirov (Russia). A minimal significance of price factors has been revealed in the process of the market analysis. This suggests that a lower price does not guarantee an increase in consumer demand. Thus, factors of non-price competition are of great importance in the market in question. The expert survey has identified the factors of non-price competition which influence consumer perceptions. A perceptual map has been constructed on the basis of the identified factors by means of the factor analysis to determine the positioning of each high-rise building relative to the consumer requirements. None of the high-rise residential buildings in the market in question meets the consumers' expectations of an "ideal facility".

Evaluation/modification of IDOT foundation piling design and construction policy.

DOT National Transportation Integrated Search

2009-03-01

The Illinois Department of Transportation (IDOT) estimates pile lengths based on a static analysis method; : however, the final length of the pile is determined with a dynamic formula based on the pile driving resistance : exhibited in the field. Bec...

Power, Revisited

ERIC Educational Resources Information Center

Roscigno, Vincent J.

2011-01-01

Power is a core theoretical construct in the field with amazing utility across substantive areas, levels of analysis and methodologies. Yet, its use along with associated assumptions--assumptions surrounding constraint vs. action and specifically organizational structure and rationality--remain problematic. In this article, and following an…

Construction and manipulation of functional three-dimensional droplet networks.

PubMed

Wauer, Tobias; Gerlach, Holger; Mantri, Shiksha; Hill, Jamie; Bayley, Hagan; Sapra, K Tanuj

2014-01-28

Previously, we reported the manual assembly of lipid-coated aqueous droplets in oil to form two-dimensional (2D) networks in which the droplets are connected through single lipid bilayers. Here we assemble lipid-coated droplets in robust, freestanding 3D geometries: for example, a 14-droplet pyramidal assembly. The networks are designed, and each droplet is placed in a designated position. When protein pores are inserted in the bilayers between specific constituent droplets, electrical and chemical communication pathways are generated. We further describe an improved means to construct 3D droplet networks with defined organizations by the manipulation of aqueous droplets containing encapsulated magnetic beads. The droplets are maneuvered in a magnetic field to form simple construction modules, which are then used to form larger 2D and 3D structures including a 10-droplet pyramid. A methodology to construct freestanding, functional 3D droplet networks is an important step toward the programmed and automated manufacture of synthetic minimal tissues.

3D bioprinting for vascularized tissue fabrication

PubMed Central

Richards, Dylan; Jia, Jia; Yost, Michael; Markwald, Roger; Mei, Ying

2016-01-01

3D bioprinting holds remarkable promise for rapid fabrication of 3D tissue engineering constructs. Given its scalability, reproducibility, and precise multi-dimensional control that traditional fabrication methods do not provide, 3D bioprinting provides a powerful means to address one of the major challenges in tissue engineering: vascularization. Moderate success of current tissue engineering strategies have been attributed to the current inability to fabricate thick tissue engineering constructs that contain endogenous, engineered vasculature or nutrient channels that can integrate with the host tissue. Successful fabrication of a vascularized tissue construct requires synergy between high throughput, high-resolution bioprinting of larger perfusable channels and instructive bioink that promotes angiogenic sprouting and neovascularization. This review aims to cover the recent progress in the field of 3D bioprinting of vascularized tissues. It will cover the methods of bioprinting vascularized constructs, bioink for vascularization, and perspectives on recent innovations in 3D printing and biomaterials for the next generation of 3D bioprinting for vascularized tissue fabrication. PMID:27230253

Amplification of the concept of erroneous meaning in psychodynamic science and in the consulting room.

PubMed

Brookes, Crittenden E

2007-01-01

Previous papers dealt with the concept of psyche as that dynamic field which underlies the subjective experience of mind. A new paradigm, psychodynamic science, was suggested for dealing with subjective data. The venue of the psychotherapeutic consulting room is now brought directly into science, expanding the definition of psychotherapy to include both humanistic and scientific elements. Certain concepts were introduced to amplify this new scientific model, including psyche as hypothetical construct, the concept of meaning as replacement for operational validation in scientific investigation, the synonymity of meaning and insight, and the concept of synchronicity, together with the meaning-connected affect of numinosity. The presence of unhealthy anxiety as the conservative ego attempts to preserve its integrity requires a deeper look at the concept of meaning. This leads to a distinction between meaning and erroneous meaning. The main body of this paper amplifies that distinction, and introduces the concept of intolerance of ambiguity in the understanding of erroneous meanings and their connection with human neurosis.

Strategies of molecular imprinting-based fluorescence sensors for chemical and biological analysis.

PubMed

Yang, Qian; Li, Jinhua; Wang, Xiaoyan; Peng, Hailong; Xiong, Hua; Chen, Lingxin

2018-07-30

One pressing concern today is to construct sensors that can withstand various disturbances for highly selective and sensitive detecting trace analytes in complicated samples. Molecularly imprinted polymers (MIPs) with tailor-made binding sites are preferred to be recognition elements in sensors for effective targets detection, and fluorescence measurement assists in highly sensitive detection and user-friendly control. Accordingly, molecular imprinting-based fluorescence sensors (MI-FL sensors) have attracted great research interest in many fields such as chemical and biological analysis. Herein, we comprehensively review the recent advances in MI-FL sensors construction and applications, giving insights on sensing principles and signal transduction mechanisms, focusing on general construction strategies for intrinsically fluorescent or nonfluorescent analytes and improvement strategies in sensing performance, particularly in sensitivity. Construction strategies are well overviewed, mainly including the traditional indirect methods of competitive binding against pre-bound fluorescent indicators, employment of fluorescent functional monomers and embedding of fluorescence substances, and novel rational designs of hierarchical architecture (core-shell/hollow and mesoporous structures), post-imprinting modification, and ratiometric fluorescence detection. Furthermore, MI-FL sensor based microdevices are discussed, involving micromotors, test strips and microfluidics, which are more portable for rapid point-of-care detection and in-field diagnosing. Finally, the current challenges and future perspectives of MI-FL sensors are proposed. Copyright © 2018 Elsevier B.V. All rights reserved.

Social construction: vistas in clinical child and adolescent psychology.

PubMed

Gergen, Kenneth J; Lightfoot, Cynthia; Sydow, Lisa

2004-06-01

We explore here the potentials of a social constructionist orientation to knowledge for research and clinical practice. Dialogues on social construction emphasize the communal origins of knowledge. They stress the cultural basis of knowledge claims, the significance of language, the value saturation of all knowledge, and the significance of relationships as opposed to individuals. An initial illustration of constructionism in action centers on adolescent risk behavior. Such behavior is often constructed negatively within popular writings and the social science and thus ignores the meaning of such actions to the adolescents themselves. Discourse analysis indicates that for adolescents risky behavior serves important functions of enhancing group solidarity and establishing positive identity. A second illustration, exploring the implications of constructionism for therapy, places a strong emphasis on the therapist as a collaborator in the building of meaning. Traditional investments in diagnosis and treatment are replaced with the collaborative creation of new possibilities for action.

Multi-site study of diffusion metric variability: effects of site, vendor, field strength, and echo time on regions-of-interest and histogram-bin analyses.

PubMed

Helmer, K G; Chou, M-C; Preciado, R I; Gimi, B; Rollins, N K; Song, A; Turner, J; Mori, S

2016-02-27

It is now common for magnetic-resonance-imaging (MRI) based multi-site trials to include diffusion-weighted imaging (DWI) as part of the protocol. It is also common for these sites to possess MR scanners of different manufacturers, different software and hardware, and different software licenses. These differences mean that scanners may not be able to acquire data with the same number of gradient amplitude values and number of available gradient directions. Variability can also occur in achievable b-values and minimum echo times. The challenge of a multi-site study then, is to create a common protocol by understanding and then minimizing the effects of scanner variability and identifying reliable and accurate diffusion metrics. This study describes the effect of site, scanner vendor, field strength, and TE on two diffusion metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA) using two common analyses (region-of-interest and mean-bin value of whole brain histograms). The goal of the study was to identify sources of variability in diffusion-sensitized imaging and their influence on commonly reported metrics. The results demonstrate that the site, vendor, field strength, and echo time all contribute to variability in FA and MD, though to different extent. We conclude that characterization of the variability of DTI metrics due to site, vendor, field strength, and echo time is a worthwhile step in the construction of multi-center trials.

Classification of Arnold-Beltrami flows and their hidden symmetries

NASA Astrophysics Data System (ADS)

Fré, P.; Sorin, A. S.

2015-07-01

In the context of mathematical hydrodynamics, we consider the group theory structure which underlies the so named ABC flows introduced by Beltrami, Arnold and Childress. Main reference points are Arnold's theorem stating that, for flows taking place on compact three manifolds ℳ3, the only velocity fields able to produce chaotic streamlines are those satisfying Beltrami equation and the modern topological conception of contact structures, each of which admits a representative contact one-form also satisfying Beltrami equation. We advocate that Beltrami equation is nothing else but the eigenstate equation for the first order Laplace-Beltrami operator ★ g d, which can be solved by using time-honored harmonic analysis. Taking for ℳ3, a torus T 3 constructed as ℝ3/Λ, where Λ is a crystallographic lattice, we present a general algorithm to construct solutions of the Beltrami equation which utilizes as main ingredient the orbits under the action of the point group B A of three-vectors in the momentum lattice *Λ. Inspired by the crystallographic construction of space groups, we introduce the new notion of a Universal Classifying Group which contains all space groups as proper subgroups. We show that the ★ g d eigenfunctions are naturally arranged into irreducible representations of and by means of a systematic use of the branching rules with respect to various possible subgroups we search and find Beltrami fields with non trivial hidden symmetries. In the case of the cubic lattice the point group is the proper octahedral group O24 and the Universal Classifying Group is a finite group G1536 of order |G1536| = 1536 which we study in full detail deriving all of its 37 irreducible representations and the associated character table. We show that the O24 orbits in the cubic lattice are arranged into 48 equivalence classes, the parameters of the corresponding Beltrami vector fields filling all the 37 irreducible representations of G1536. In this way we obtain an exhaustive classification of all generalized ABC- flows and of their hidden symmetries. We make several conceptual comments about the need of a field-theory yielding Beltrami equation as a field equation and/or an instanton equation and on the possible relation of Arnold-Beltrami flows with (supersymmetric) Chern-Simons gauge theories. We also suggest linear generalizations of Beltrami equation to higher odd-dimensions that are different from the non-linear one proposed by Arnold and possibly make contact with M-theory and the geometry of flux-compactifications.

The McMillan and Newton polygons of a feedback system and the construction of root loci

NASA Technical Reports Server (NTRS)

Byrnes, C. I.; Stevens, P. K.

1982-01-01

The local behaviour of root loci around zeros and poles is investigated. This is done by relating the Newton diagrams which arise in the local analysis to the McMillan structure of the open-loop system, by means of what we shall call the McMillan polygon. This geometric construct serves to clarify the precise relationship between the McMillan structure, the principal structure, and the branching patterns of the root loci. In addition, several rules are obtained which are useful in the construction of the root loci of multivariable control systems.

Consistent multiphase-field theory for interface driven multidomain dynamics

NASA Astrophysics Data System (ADS)

Tóth, Gyula I.; Pusztai, Tamás; Gránásy, László

2015-11-01

We present a multiphase-field theory for describing pattern formation in multidomain and/or multicomponent systems. The construction of the free energy functional and the dynamic equations is based on criteria that ensure mathematical and physical consistency. We first analyze previous multiphase-field theories and identify their advantageous and disadvantageous features. On the basis of this analysis, we introduce a way of constructing the free energy surface and derive a generalized multiphase description for arbitrary number of phases (or domains). The presented approach retains the variational formalism, reduces (or extends) naturally to lower (or higher) number of fields on the level of both the free energy functional and the dynamic equations, enables the use of arbitrary pairwise equilibrium interfacial properties, penalizes multiple junctions increasingly with the number of phases, ensures non-negative entropy production and the convergence of the dynamic solutions to the equilibrium solutions, and avoids the appearance of spurious phases on binary interfaces. The approach is tested for multicomponent phase separation and grain coarsening.

Lattice modeling and application of independent component analysis to high power, long bunch beams in the Los Alamos Proton Storage Ring

NASA Astrophysics Data System (ADS)

Kolski, Jeffrey

The linear lattice properties of the Proton Storage Ring (PSR) at the Los Alamos Neutron Science Center (LANSCE) in Los Alamos, NM were measured and applied to determine a better linear accelerator model. We found that the initial model was deficient in predicting the vertical focusing strength. The additional vertical focusing was located through fundamental understanding of experiment and statistically rigorous analysis. An improved model was constructed and compared against the initial model and measurement at operation set points and set points far away from nominal and was shown to indeed be an enhanced model. Independent component analysis (ICA) is a tool for data mining in many fields of science. Traditionally, ICA is applied to turn-by-turn beam position data as a means to measure the lattice functions of the real machine. Due to the diagnostic setup for the PSR, this method is not applicable. A new application method for ICA is derived, ICA applied along the length of the bunch. The ICA modes represent motions within the beam pulse. Several of the dominate ICA modes are experimentally identified.

Military applications and examples of near-surface seismic surface wave methods (Invited)

NASA Astrophysics Data System (ADS)

sloan, S.; Stevens, R.

2013-12-01

Although not always widely known or publicized, the military uses a variety of geophysical methods for a wide range of applications--some that are already common practice in the industry while others are truly novel. Some of those applications include unexploded ordnance detection, general site characterization, anomaly detection, countering improvised explosive devices (IEDs), and security monitoring, to name a few. Techniques used may include, but are not limited to, ground penetrating radar, seismic, electrical, gravity, and electromagnetic methods. Seismic methods employed include surface wave analysis, refraction tomography, and high-resolution reflection methods. Although the military employs geophysical methods, that does not necessarily mean that those methods enable or support combat operations--often times they are being used for humanitarian applications within the military's area of operations to support local populations. The work presented here will focus on the applied use of seismic surface wave methods, including multichannel analysis of surface waves (MASW) and backscattered surface waves, often in conjunction with other methods such as refraction tomography or body-wave diffraction analysis. Multiple field examples will be shown, including explosives testing, tunnel detection, pre-construction site characterization, and cavity detection.

Numerical Modeling of Local Penetration of Chloride-Containing Medium into Construction Elements Made of Reinforced Concrete

NASA Astrophysics Data System (ADS)

Ovchinnikov, I. I.; Snezhkina, O. V.; Ovchinnikov, I. G.

2017-11-01

The task of modeling the kinetics of chloride-containing medium penetration into construction elements out of reinforced concrete that have partially damaged anti-corrosion protective coatings is being discussed. As a result, chlorides penetrate the construction element via local surface areas which leads to irregularities between chloride dispersion volumes. The kinetics of chloride penetration is described by the equation of diffusion to solve which the CONDUCT software complex by professor S. Patankar was used. The methodology used to solve the diffusional equation is described. The results of the evaluation of concentration field in the axial section of a cylindrical construction element, which was centrally reinforced, are given. The chloride diffusion was symmetrical to the axis, the medium was applied through the central ring area equal to one third of the side surface area while the rest of the surface was isolated. It was shown that the methodology of evaluation and its algorithm allow one to evaluate the concentration field of chlorides in reinforced concrete structural elements under local or asymmetrical action of the chloride - containing medium. The example given illustrates that after a certain time interval critical the concentration of chlorides develops even in protected areas which are located far from the initial damaged area. This means that the corrosion destruction of reinforced elements develops not only in the immediate damage area, but also further away from it.

Environmental Assessment: Hurlburt Field Soundside Boathouse and Restroom Facility Construction

DTIC Science & Technology

2007-08-01

seq., and Air Force Instruction (AFI) 32-7061, The Environmental Impact Analysis Process, the USAF concludes that the Proposed Action will have no...U.S.C.) §4321, et seq., and Air Force Instruction (AFI) 32-7061, The Environmental Impact Analysis Process, the USAF concludes that the Proposed...et seq. • AFI 32-7061, The Environmental Impact Analysis Process These regulations require federal agencies to analyze the potential environmental

Mott-Hubbard transition and Anderson localization: A generalized dynamical mean-field theory approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuchinskii, E. Z.; Nekrasov, I. A.; Sadovskii, M. V.

The DOS, the dynamic (optical) conductivity, and the phase diagram of a strongly correlated and strongly disordered paramagnetic Anderson-Hubbard model are analyzed within the generalized dynamical mean field theory (DMFT + {sigma} approximation). Strong correlations are taken into account by the DMFT, and disorder is taken into account via an appropriate generalization of the self-consistent theory of localization. The DMFT effective single-impurity problem is solved by a numerical renormalization group (NRG); we consider the three-dimensional system with a semielliptic DOS. The correlated metal, Mott insulator, and correlated Anderson insulator phases are identified via the evolution of the DOS and dynamicmore » conductivity, demonstrating both the Mott-Hubbard and Anderson metal-insulator transition and allowing the construction of the complete zero-temperature phase diagram of the Anderson-Hubbard model. Rather unusual is the possibility of a disorder-induced Mott insulator-to-metal transition.« less

Modeling unsteady sound refraction by coherent structures in a high-speed jet

NASA Astrophysics Data System (ADS)

Kan, Pinqing; Lewalle, Jacques

2011-11-01

We construct a visual model for the unsteady refraction of sound waves from point sources in a Ma = 0.6 jet. The mass and inviscid momentum equations give an equation governing acoustic fluctuations, including anisotropic propagation, attenuation and sources; differences with Lighthill's equation will be discussed. On this basis, the theory of characteristics gives canonical equations for the acoustic paths from any source into the far field. We model a steady mean flow in the near-jet region including the potential core and the mixing region downstream of its collapse, and model the convection of coherent structures as traveling wave perturbations of this mean flow. For a regular distribution of point sources in this region, we present a visual rendition of fluctuating distortion, lensing and deaf spots from the viewpoint of a far-field observer. Supported in part by AFOSR Grant FA-9550-10-1-0536 and by a Syracuse University Graduate Fellowship.

Central corneal thickness and progression of the visual field and optic disc in glaucoma

PubMed Central

Chauhan, B C; Hutchison, D M; LeBlanc, R P; Artes, P H; Nicolela, M T

2005-01-01

Aims: To determine whether central corneal thickness (CCT) is a significant predictor of visual field and optic disc progression in open angle glaucoma. Methods: Data were obtained from a prospective study of glaucoma patients tested with static automated perimetry and confocal scanning laser tomography every 6 months. Progression was determined using a trend based approach called evidence of change (EOC) analysis in which sectoral ordinal scores based on the significance of regression coefficients of visual field pattern deviation and neuroretinal rim area over time are summed. Visual field progression was also determined using the event based glaucoma change probability (GCP) analysis using both total and pattern deviation. Results: The sample contained 101 eyes of 54 patients (mean (SD) age 56.5 (9.8) years) with a mean follow up of 9.2 (0.7) years and 20.7 (2.3) sets of examinations every 6 months. Lower CCT was associated with worse baseline visual fields and lower mean IOP in the follow up. In the longitudinal analysis CCT was not correlated with the EOC scores for visual field or optic disc change. In the GCP analyses, there was a tendency for groups classified as progressing to have lower CCT compared to non-progressing groups. In a multivariate analyses accounting for IOP, the opposite was found, whereby higher CCT was associated with visual field progression. None of the independent factors were predictive of optic disc progression. Conclusions: In this cohort of patients with established glaucoma, CCT was not a useful index in the risk assessment of visual field and optic disc progression. PMID:16024855

Identifying the stored energy of a hyperelastic structure by using an attenuated Landweber method

NASA Astrophysics Data System (ADS)

Seydel, Julia; Schuster, Thomas

2017-12-01

We consider the nonlinear inverse problem of identifying the stored energy function of a hyperelastic material from full knowledge of the displacement field as well as from surface sensor measurements. The displacement field is represented as a solution of Cauchy’s equation of motion, which is a nonlinear elastic wave equation. Hyperelasticity means that the first Piola-Kirchhoff stress tensor is given as the gradient of the stored energy function. We assume that a dictionary of suitable functions is available. The aim is to recover the stored energy with respect to this dictionary. The considered inverse problem is of vital interest for the development of structural health monitoring systems which are constructed to detect defects in elastic materials from boundary measurements of the displacement field, since the stored energy encodes the mechanical properties of the underlying structure. In this article we develop a numerical solver using the attenuated Landweber method. We show that the parameter-to-solution map satisfies the local tangential cone condition. This result can be used to prove local convergence of the attenuated Landweber method in the case that the full displacement field is measured. In our numerical experiments we demonstrate how to construct an appropriate dictionary and show that our method is well suited to localize damages in various situations.

Atomically flat superconducting nanofilms: multiband properties and mean-field theory

NASA Astrophysics Data System (ADS)

Shanenko, A. A.; Aguiar, J. Albino; Vagov, A.; Croitoru, M. D.; Milošević, M. V.

2015-05-01

Recent progress in materials synthesis enabled fabrication of superconducting atomically flat single-crystalline metallic nanofilms with thicknesses down to a few monolayers. Interest in such nano-thin systems is attracted by the dimensional 3D-2D crossover in their coherent properties which occurs with decreasing the film thickness. The first fundamental aspect of this crossover is dictated by the Mermin-Wagner-Hohenberg theorem and concerns frustration of the long-range order due to superconductive fluctuations and the possibility to track its impact with an unprecedented level of control. The second important aspect is related to the Fabri-Pérot modes of the electronic motion strongly bound in the direction perpendicular to the nanofilm. The formation of such modes results in a pronounced multiband structure that changes with the nanofilm thickness and affects both the mean-field behavior and superconductive fluctuations. Though the subject is very rich in physics, it is scarcely investigated to date. The main obstacle is that there are no manageable models to study a complex magnetic response in this case. Full microscopic consideration is rather time consuming, if practicable at all, while the standard Ginzburg-Landau theory is not applicable. In the present work we review the main achievements in the subject to date, and construct and justify an efficient multiband mean-field formalism which allows for numerical and even analytical treatment of nano-thin superconductors in applied magnetic fields.

Review of the Review: Constructing the Identity of Comparative Education

ERIC Educational Resources Information Center

Wolhuter, C. C.

2008-01-01

The aim of this article is the explication of the identity of Comparative Education and a critical reflection thereon, by means of a journal analysis of articles published in the "Comparative Education Review" during the first 50 years of its existence. The 1157 articles were analyzed under the following rubrics: levels of analysis of articles;…

Identification of a Group's Physiological Synchronization with Earth's Magnetic Field.

PubMed

Timofejeva, Inga; McCraty, Rollin; Atkinson, Mike; Joffe, Roza; Vainoras, Alfonsas; Alabdulgader, Abdullah A; Ragulskis, Minvydas

2017-09-01

A new analysis technique for the evaluation of the degree of synchronization between the physiological state of a group of people and changes in the Earth's magnetic field based on their cardiac inter-beat intervals was developed and validated. The new analysis method was then used to identify clusters of similar synchronization patterns in a group of 20 individuals over a two-week period. The algorithm for the identification of slow wave dynamics for every person was constructed in order to determine meaningful interrelationships between the participants and the local magnetic field data. The results support the hypothesis that the slow wave rhythms in heart rate variability can synchronize with changes in local magnetic field data, and that the degree of synchronization is affected by the quality of interpersonal relationships.

A comparison of two laboratories for the measurement of wood dust using button sampler and diffuse reflection infrared Fourier-transform spectroscopy (DRIFTS).

PubMed

Chirila, Madalina M; Sarkisian, Khachatur; Andrew, Michael E; Kwon, Cheol-Woong; Rando, Roy J; Harper, Martin

2015-04-01

The current measurement method for occupational exposure to wood dust is by gravimetric analysis and is thus non-specific. In this work, diffuse reflection infrared Fourier transform spectroscopy (DRIFTS) for the analysis of only the wood component of dust was further evaluated by analysis of the same samples between two laboratories. Field samples were collected from six wood product factories using 25-mm glass fiber filters with the Button aerosol sampler. Gravimetric mass was determined in one laboratory by weighing the filters before and after aerosol collection. Diffuse reflection mid-infrared spectra were obtained from the wood dust on the filter which is placed on a motorized stage inside the spectrometer. The metric used for the DRIFTS analysis was the intensity of the carbonyl band in cellulose and hemicellulose at ~1735 cm(-1). Calibration curves were constructed separately in both laboratories using the same sets of prepared filters from the inhalable sampling fraction of red oak, southern yellow pine, and western red cedar in the range of 0.125-4 mg of wood dust. Using the same procedure in both laboratories to build the calibration curve and analyze the field samples, 62.3% of the samples measured within 25% of the average result with a mean difference between the laboratories of 18.5%. Some observations are included as to how the calibration and analysis can be improved. In particular, determining the wood type on each sample to allow matching to the most appropriate calibration increases the apparent proportion of wood dust in the sample and this likely provides more realistic DRIFTS results. Published by Oxford University Press on behalf of the British Occupational Hygiene Society 2014.

Pitfalls in velocity analysis for strongly contrasting, layered media - Example from the Chalk Group, North Sea

NASA Astrophysics Data System (ADS)

Montazeri, Mahboubeh; Uldall, Anette; Moreau, Julien; Nielsen, Lars

2018-02-01

Knowledge about the velocity structure of the subsurface is critical in key seismic processing sequences, for instance, migration, depth conversion, and construction of initial P- and S-wave velocity models for full-waveform inversion. Therefore, the quality of subsurface imaging is highly dependent upon the quality of the seismic velocity analysis. Based on a case study from the Danish part of the North Sea, we show how interference caused by multiples, converted waves, and thin-layer effects may lead to incorrect velocity estimation, if such effects are not accounted for. Seismic wave propagation inside finely layered reservoir rocks dominated by chalk is described by two-dimensional finite-difference wave field simulation. The rock physical properties used for the modeling are based on an exploration well from the Halfdan field in the Danish sector of the North Sea. The modeling results are compared to seismic data from the study area. The modeling shows that interference of primaries with multiples, converted waves and thin-bed effects can give rise to strong anomalies in standard velocity analysis plots. Consequently, root-mean-square (RMS) velocity profiles may be erroneously picked. In our study area, such mis-picking can introduce errors in, for example, the thickness estimation of the layers near the base of the studied sedimentary strata by 11% to 26%. Tests show that front muting and bandpass filtering cannot significantly improve the quality of velocity analysis in our study. However, we notice that spiking deconvolution applied before velocity analysis may to some extent reduce the impact of interference and, therefore, reduce the risk of erroneous picking of the velocity function.

Electronic States and Persistent Currents in Nanowire Quantum Ring

NASA Astrophysics Data System (ADS)

Kokurin, I. A.

2018-04-01

The new model of a quantum ring (QR) defined inside a nanowire (NW) is proposed. The one-particle Hamiltonian for electron in [111]-oriented NW QR is constructed taking into account both Rashba and Dresselhaus spin-orbit coupling (SOC). The energy levels as a function of magnetic field are found using the exact numerical diagonalization. The persistent currents (both charge and spin) are calculated. The specificity of SOC and arising anticrossings in energy spectrum lead to unusual features in persistent current behavior. The variation of magnetic field or carrier concentration by means of gate can lead to pure spin persistent current with the charge current being zero.

Self-synchronizing Schlieren photography and interferometry for the visualization of unsteady transonic flows

NASA Technical Reports Server (NTRS)

Kadlec, R.

1979-01-01

The use of self synchronizing stroboscopic Schlieren and laser interferometer systems to obtain quantitative space time measurements of distinguished flow surfaces, steakline patterns, and the density field of two dimensional flows that exhibit a periodic content was investigated. A large field single path stroboscopic Schlieren system was designed, constructed and successfully applied to visualize four periodic flows: near wake behind an oscillating airfoil; edge tone sound generation; 2-D planar wall jet; and axisymmetric pulsed sonic jet. This visualization technique provides an effective means of studying quasi-periodic flows in real time. The image on the viewing screen is a spatial signal average of the coherent periodic motion rather than a single realization, the high speed motion of a quasi-periodic flow can be reconstructed by recording photographs of the flow at different fixed time delays in one cycle. The preliminary design and construction of a self synchronizing stroboscopic laser interferometer with a modified Mach-Zehnder optical system is also reported.

Sensitivity vector fields in time-delay coordinate embeddings: theory and experiment.

PubMed

Sloboda, A R; Epureanu, B I

2013-02-01

Identifying changes in the parameters of a dynamical system can be vital in many diagnostic and sensing applications. Sensitivity vector fields (SVFs) are one way of identifying such parametric variations by quantifying their effects on the morphology of a dynamical system's attractor. In many cases, SVFs are a more effective means of identification than commonly employed modal methods. Previously, it has only been possible to construct SVFs for a given dynamical system when a full set of state variables is available. This severely restricts SVF applicability because it may be cost prohibitive, or even impossible, to measure the entire state in high-dimensional systems. Thus, the focus of this paper is constructing SVFs with only partial knowledge of the state by using time-delay coordinate embeddings. Local models are employed in which the embedded states of a neighborhood are weighted in a way referred to as embedded point cloud averaging. Application of the presented methodology to both simulated and experimental time series demonstrates its utility and reliability.

Data-Driven Modeling of Complex Systems by means of a Dynamical ANN

NASA Astrophysics Data System (ADS)

Seleznev, A.; Mukhin, D.; Gavrilov, A.; Loskutov, E.; Feigin, A.

2017-12-01

The data-driven methods for modeling and prognosis of complex dynamical systems become more and more popular in various fields due to growth of high-resolution data. We distinguish the two basic steps in such an approach: (i) determining the phase subspace of the system, or embedding, from available time series and (ii) constructing an evolution operator acting in this reduced subspace. In this work we suggest a novel approach combining these two steps by means of construction of an artificial neural network (ANN) with special topology. The proposed ANN-based model, on the one hand, projects the data onto a low-dimensional manifold, and, on the other hand, models a dynamical system on this manifold. Actually, this is a recurrent multilayer ANN which has internal dynamics and capable of generating time series. Very important point of the proposed methodology is the optimization of the model allowing us to avoid overfitting: we use Bayesian criterion to optimize the ANN structure and estimate both the degree of evolution operator nonlinearity and the complexity of nonlinear manifold which the data are projected on. The proposed modeling technique will be applied to the analysis of high-dimensional dynamical systems: Lorenz'96 model of atmospheric turbulence, producing high-dimensional space-time chaos, and quasi-geostrophic three-layer model of the Earth's atmosphere with the natural orography, describing the dynamics of synoptical vortexes as well as mesoscale blocking systems. The possibility of application of the proposed methodology to analyze real measured data is also discussed. The study was supported by the Russian Science Foundation (grant #16-12-10198).

Preliminary study on enhancing waste management best practice model in Malaysia construction industry

NASA Astrophysics Data System (ADS)

Jamaludin, Amril Hadri; Karim, Nurulzatushima Abdul; Noor, Raja Nor Husna Raja Mohd; Othman, Nurulhidayah; Malik, Sulaiman Abdul

2017-08-01

Construction waste management (CWM) is the practice of minimizing and diverting construction waste, demolition debris, and land-clearing debris from disposal and redirecting recyclable resources back into the construction process. Best practice model means best choice from the collection of other practices that was built for purpose of construction waste management. The practice model can help the contractors in minimizing waste before the construction activities will be started. The importance of minimizing wastage will have direct impact on time, cost and quality of a construction project. This paper is focusing on the preliminary study to determine the factors of waste generation in the construction sites and identify the effectiveness of existing construction waste management practice conducted in Malaysia. The paper will also include the preliminary works of planned research location, data collection method, and analysis to be done by using the Analytical Hierarchy Process (AHP) to help in developing suitable waste management best practice model that can be used in the country.

Elastic S-matrices in (1 + 1) dimensions and Toda field theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christe, P.; Mussardo, G.

Particular deformations of 2-D conformal field theory lead to integrable massive quantum field theories. These can be characterized by the relative scattering data. This paper proposes a general scheme for classifying the elastic nondegenerate S-matrix in (1 + 1) dimensions starting from the possible boot-strap processes and the spins of the conserved currents. Their identification with the S-matrix coming from the Toda field theory is analyzed. The authors discuss both cases of Toda field theory constructed with the simply-laced Dynkin diagrams and the nonsimply-laced ones. The authors present the results of the perturbative analysis and their geometrical interpretations.

The development of an instrument to assess chemistry perceptions

NASA Astrophysics Data System (ADS)

Wells, Raymond R.

The instrument, developed in this study, attempted to correct the deficiencies of previous instruments. Statements of belief and opinion can be validly included under the construct of chemistry perceptions. Further, statements that might be better characterized as science attitudes, math attitudes, or attitudes toward a specific course or program were not included. Eliminating statements of math anxiety and test anxiety insured that responses to statements of anxiety were perceptions of anxiety solely related to chemistry. The results of the expert judges' responses to the Validation of Proposed Perception Statements forms were detailed to establish construct and content validity. The nature of Likert scale construction and calculation of internal consistency also supported the validity of the instrument. A pilot Chemistry Perception Questionnaire (CPQ) was then constructed based on agreement of the appropriate subscale and mean importance of the perception statements. The pilot CPQ results were subjected to an item analysis based on three sets of statistics: the frequency of each response and the percentage of respondents making each response for each perception statement, the mean and standard deviations for each item, and the item discrimination index which correlated the item scores with the subscale scores. With no zero or negative correlations to the subscale scores, it was not necessary to replace any of the perception statements contained in the pilot instrument. Therefore, the piloted Chemistry Perception Questionnaire became the final instrument. Factor analysis confirmed the multidimensionality of the instrument. The instrument was administered twice with a separation interval of approximately one month in order to perform a test-retest reliability analysis. One hundred and forty-one pairs were matched and results detailed. The correlation between forms, for the total instrument, was 0.9342. The mean coefficient alpha, for the total instrument, was 0.9495. With test-retest correlations and alphas exceeding 0.70 for all seven subscales and the total instrument, it was determined that the Chemistry Perception Questionnaire instrument achieved reasonably high reliability estimations.

Adaptation of FIBER for Forest Inventory and Analysis growth projections in the State of Maine

Treesearch

Dale S. Solomon; Thomas B. Brann; Lawrence E. Caldwell

2000-01-01

The model FIBER (Forest Increment Based on Ecological Rationale) was selected by the Technical Review Team on the Sustainability of Timber Supplies in the State of Maine to construct yield information using USDA Forest Service Forest Inventory and Analysis (FIA) field data. FIBER habitat criteria based on soil characteristics, species composition of overstory, and...

Using link analysis to explore the impact of the physical environment on pharmacist tasks.

PubMed

Lester, Corey A; Chui, Michelle A

2016-01-01

National community pharmacy organizations have been redesigning pharmacies to better facilitate direct patient care. However, evidence suggests that changing the physical layout of a pharmacy prior to understanding how the environment impacts pharmacists' work may not achieve the desired benefits. This study describes an objective method to understanding how the physical layout of the pharmacy may affect how pharmacists perform tasks. Link analysis is a systems engineering method used to describe the influence of the physical environment on task completion. This study used a secondary data set of field notes collected from 9 h of direct observation in one mass-merchandise community pharmacy in the U.S. State, Wisconsin. A node is an individual location in the environment. A link is the movement between two nodes. Tasks were inventoried and task themes identified. The mean, minimum, and maximum number of links needed to complete each task were then determined and used to construct a link table. A link diagram is a graphical display showing the links in conjunction with the physical layout of the pharmacy. A total of 92 unique tasks were identified resulting in 221 links. Tasks were sorted into five themes: patient care activities, insurance issues, verifying prescriptions, filling prescriptions, and other. Insurance issues required the greatest number of links with a mean of 4.75. Verifying prescriptions and performing patient care were the most commonly performed tasks with 36 and 30 unique task occurrences, respectively. Link analysis provides an objective method for identifying how a pharmacist interacts with the physical environment to complete tasks. This method provides designers with useful information to target interventions to improve the effectiveness of pharmacist work. Analysis beyond link analysis should be considered for large scale system redesign. Copyright © 2015 Elsevier Inc. All rights reserved.

Harmonic analysis of the precipitation in Greece

NASA Astrophysics Data System (ADS)

Nastos, P. T.; Zerefos, C. S.

2009-04-01

Greece is a country with a big variety of climates due to its geographical position, to the many mountain ranges and also to the multifarious and long coastline. The mountainous volumes are of such orientation that influences the distribution of the precipitation, having as a result, Western Greece to present great differentiations from Central and Eastern Greece. The application of harmonic analysis to the annual variability of precipitation is the goal of this study, so that the components, which compose the annual variability, be elicited. For this purpose, the mean monthly precipitation data from 30 meteorological stations of National Meteorological Service were used for the time period 1950-2000. The initial target is to reduce the number of variables and to detect structure in the relationships between variables. The most commonly used technique for this purpose is the application of Factor Analysis to a table having as columns the meteorological stations-variables and rows the monthly mean precipitation, so that 2 main factors were calculated, which explain the 98% of total variability of precipitation in Greece. Factor 1, representing the so-called uniform field and interpreting the most of the total variance, refers in fact to the Mediterranean depressions, affecting mainly the West of Greece and also the East Aegean and the Asia Minor coasts. In the process, the Fourier Analysis was applied to the factor scores extracted from the Factor Analysis, so that 2 harmonic components are resulted, which explain above the 98% of the total variability of each main factor, and are due to different synoptic and thermodynamic processes associated with Greece's precipitation construction. Finally, the calculation of the time of occurrence of the maximum precipitation, for each harmonic component of each one of the two main factors, gives the spatial distribution of appearance of the maximum precipitation in the Hellenic region.

The relationship among leadership, innovation and knowledge sharing: A guidance for analysis.

PubMed

Elrehail, Hamzah

2018-08-01

This data article describes the contingent role of knowledge sharing between two leadership styles and innovation in higher education institutions in non-western countries. The dataset investigates the second-ordered (i.e. higher construct) among the relationships of study constructs, the nested relationship which gives birth to new constructs. Further, this dataset provides guidance for readers willing to conduct research in the management field. The dataset has been collected using a self-administered questionnaire obtained from the academic staff in the selected universities. The structural equation modeling (SEM) was applied using IBM SPSS AMOS. In this data article, several analysis techniques have been used. The results obtained from this dataset shows a significant relationship between leadership and innovation, and the results show that the moderation effect of knowledge sharing is partially supported.

Assimilation of Altimeter Data into a Quasigeostrophic Model of the Gulf Stream System. Part 1; Dynamical Considerations

NASA Technical Reports Server (NTRS)

Capotondi, Antonietta; Malanotte-Rizzoli, Paola; Holland, William R.

1995-01-01

The dynamical consequences of constraining a numerical model with sea surface height data have been investigated. The model used for this study is a quasigeostrophic model of the Gulf Stream region. The data that have been assimilated are maps of sea surface height obtained as the superposition of sea surface height variability deduced from the Geosat altimeter measurements and a mean field constructed from historical hydrographic data. The method used for assimilating the data is the nudging technique. Nudging has been implemented in such a way as to achieve a high degree of convergence of the surface model fields toward the observations. The assimilation of the surface data is thus equivalent to the prescription of a surface pressure boundary condition. The authors analyzed the mechanisms of the model adjustment and the characteristics of the resultant equilibrium state when the surface data are assimilated. Since the surface data are the superposition of a mean component and an eddy component, in order to understand the relative role of these two components in determining the characteristics of the final equilibrium state, two different experiments have been considered: in the first experiment only the climatological mean field is assimilated, while in the second experiment the total surface streamfunction field (mean plus eddies) has been used. It is shown that the model behavior in the presence of the surface data constraint can be conveniently described in terms of baroclinic Fofonoff modes. The prescribed mean component of the surface data acts as a 'surface topography' in this problem. Its presence determines a distortion of the geostrophic contours in the subsurface layers, thus constraining the mean circulation in those layers. The intensity of the mean flow is determined by the inflow/outflow conditions at the open boundaries, as well as by eddy forcing and dissipation.

Trace radioactive impurities in final construction materials for EXO-200

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leonard, D. S.; Auty, D. J.; Didberidze, T.

Here, we report results from a systematic measurement campaign conducted to identify low radioactivity materials for the construction of the EXO-200 double beta decay experiment. Partial results from this campaign have already been reported in a 2008 paper by the EXO collaboration. Here we release the remaining data, collected since 2007, to the public. The data reported were obtained using a variety of analytic techniques. The measurement sensitivities are among the best in the field. We concluded the construction of the EXO-200 detector and Phase-I data was taken from 2011 to 2014. The detector’s extremely low background implicitly verifies themore » measurements and the analysis assumptions made during construction and reported in this paper.« less

Trace radioactive impurities in final construction materials for EXO-200

DOE PAGES

Leonard, D. S.; Auty, D. J.; Didberidze, T.; ...

2017-05-01

Here, we report results from a systematic measurement campaign conducted to identify low radioactivity materials for the construction of the EXO-200 double beta decay experiment. Partial results from this campaign have already been reported in a 2008 paper by the EXO collaboration. Here we release the remaining data, collected since 2007, to the public. The data reported were obtained using a variety of analytic techniques. The measurement sensitivities are among the best in the field. We concluded the construction of the EXO-200 detector and Phase-I data was taken from 2011 to 2014. The detector’s extremely low background implicitly verifies themore » measurements and the analysis assumptions made during construction and reported in this paper.« less

7 CFR 1738.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... financial analysis prepared by the Agency, based on the financial projections supplied by the applicant and... definition includes Variable Interest Entities as described in Financial Accounting Standards Board... required at the time the application was received by the Agency. Build-out means the construction...

7 CFR 1738.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... financial analysis prepared by the Agency, based on the financial projections supplied by the applicant and... definition includes Variable Interest Entities as described in Financial Accounting Standards Board... required at the time the application was received by the Agency. Build-out means the construction...

7 CFR 1738.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... financial analysis prepared by the Agency, based on the financial projections supplied by the applicant and... definition includes Variable Interest Entities as described in Financial Accounting Standards Board... required at the time the application was received by the Agency. Build-out means the construction...

Why developmental niche construction is not selective niche construction: and why it matters

PubMed Central

2017-01-01

In the last decade, niche construction has been heralded as the neglected process in evolution. But niche construction is just one way in which the organism's interaction with and construction of the environment can have potential evolutionary significance. The constructed environment does not just select for, it also produces new variation. Nearly 3 decades ago, and in parallel with Odling-Smee's article ‘Niche-constructing phenotypes', West and King introduced the ‘ontogenetic niche’ to give the phenomena of exogenetic inheritance a formal name. Since then, a range of fields in the life sciences and medicine has amassed evidence that parents influence their offspring by means other than DNA (parental effects), and proposed mechanisms for how heritable variation can be environmentally induced and developmentally regulated. The concept of ‘developmental niche construction’ (DNC) elucidates how a diverse range of mechanisms contributes to the transgenerational transfer of developmental resources. My most central of claims is that whereas the selective niche of niche construction theory is primarily used to explain the active role of the organism in its selective environment, DNC is meant to indicate the active role of the organism in its developmental environment. The paper highlights the differences between the construction of the selective and the developmental niche, and explores the overall significance of DNC for evolutionary theory. PMID:28839923

Exploratory Water Budget Analysis of A Transitional Premontane Cloud Forest in Costa Rica Through Undergraduate Research

NASA Astrophysics Data System (ADS)

Washington-Allen, R. A.; Buckwalter, E. H.; Moore, G. W.; Burns, J. N.; Dennis, A. R.; Dodge, O.; Guffin, E. C.; Morris, E. R.; Oien, R. P.; Orozco, G.; Peterson, A.; Teale, N. G.; Shibley, N. C.; Tourtellotte, N.; Houser, C.; Brooks, S. D.; Brumbelow, J. K.; Cahill, A. T.; Frauenfeld, O. W.; Gonzalez, E.; Hallmark, C. T.; McInnes, K. J.; Miller, G. R.; Morgan, C.; Quiring, S. M.; Rapp, A. D.; Roark, E.; Delgado, A.; Ackerson, J. P.; Arnott, R.

2012-12-01

The ecohydrology of transitional premontane cloud forests is not well understood. This problem is being addressed by a NSF Research Experience for Undergraduates (REU) study at the Texas A&M University Soltis Center for Research & Education in Costa Rica. Exploratory analysis of the water budget within a 20-ha watershed was used to connect three faculty-mentored research areas in ecohydrology, climate, and soil sciences and highlight the roles of 12 undergraduate researchers from 12 different universities. The water budget model is Q = Pn - E - T + ΔG + ΔS where Q = runoff, Pn = net precipitation, E = evaporation, T = transpiration, and ΔG and ΔS are change in groundwater soil water storage, respectively. Additionally, Pn = Pg - I = Tf + Sf + D, where Pg = gross precipitation, I/ΔI = canopy interception or storage, Tf = throughfall, Sf = stemflow, and D = canopy drip. The following terms were well understood Pg (satellite = 34-mm and tower = 38.1-mm) and Q from a recently constructed v-notch weir. We moderately understand Tf + D (30.9-mm from an array of forest rain gages), ΔI (7.2-mm) related to Sf, and T (10.4-mm measured with sapflow sensors). We found that soils were clay loam to silty loam textured Andisols on saprolitic tuft with a mean potential ΔS of 398 mm H2O under laboratory conditions, but in the field the following terms are almost completely unknown and require further field studies including E, ΔG, and ΔS. Recent installation of piezometers will address ΔG. Temporal scaling of measurements to a 1-week period was a challenge as well as the construction, deployment and calibration of instruments. However, this exploration allowed us to determine measurement uncertainties in the water budget, e.g., E, and to set future areas of research to address these uncertainties.

Temporal Variation of the Rotation of the Solar Mean Magnetic Field

NASA Astrophysics Data System (ADS)

Xie, J. L.; Shi, X. J.; Xu, J. C.

2017-04-01

Based on continuous wavelet transformation analysis, the daily solar mean magnetic field (SMMF) from 1975 May 16 to 2014 July 31 is analyzed to reveal its rotational behavior. Both the recurrent plot in Bartels form and the continuous wavelet transformation analysis show the existence of rotational modulation in the variation of the daily SMMF. The dependence of the rotational cycle lengths on solar cycle phase is also studied, which indicates that the yearly mean rotational cycle lengths generally seem to be longer during the rising phase of solar cycles and shorter during the declining phase. The mean rotational cycle length for the rising phase of all of the solar cycles in the considered time is 28.28 ± 0.67 days, while for the declining phase it is 27.32 ± 0.64 days. The difference of the mean rotational cycle lengths between the rising phase and the declining phase is 0.96 days. The periodicity analysis, through the use of an auto-correlation function, indicates that the rotational cycle lengths have a significant period of about 10.1 years. Furthermore, the cross-correlation analysis indicates that there exists a phase difference between the rotational cycle lengths and solar activity.

Competences in Romanian Higher Education--An Empirical Investigation for the Business Sector

ERIC Educational Resources Information Center

Deaconu, Adela; Nistor, Cristina Silvia

2017-01-01

This research study particularizes the general descriptions of the European Qualifications Framework for Lifelong Learning, as compiled and developed within the Romanian qualification framework, to the business and economics field in general and to the property economic analysis and valuation field in particular. By means of an empirical analysis,…

LADO as a Language Test: Issues of Validity

ERIC Educational Resources Information Center

McNamara, Tim; Van Den Hazelkamp, Carolien; Verrips, Maaike

2016-01-01

This article brings together the theoretical field of language testing and the practical field of language analysis for the determination of the origin of asylum seekers. It considers what it would mean to think of language analysis as a form of language test, subject to the same validity constraints, and proposes a research agenda.

An imaging vector magnetograph for the next solar maximum

NASA Technical Reports Server (NTRS)

Mickey, D. L.; Labonte, B. J.; Canfield, R. C.

1989-01-01

Researchers describe the conceptual design of a new imaging vector magnetograph currently being constructed at the University of Hawaii. The instrument combines a modest solar telescope with a rotating quarter-wave plate, an acousto-optical tunable prefilter as a blocker for a servo-controlled Fabry-Perot etalon, CCD cameras, and on-line digital image processing. Its high spatial resolution (1/2 arcsec pixel size) over a large field of view (5 by 5 arcmin) will be sufficient to significantly measure, for the first time, the magnetic energy dissipated in major solar flares. Its millisecond tunability and wide spectral range (5000 to 7000 A) enable nearly simultaneous vector magnetic field measurements in the gas-pressure-dominated photosphere and magnetically-dominated chromosphere, as well as effective co-alignment with Solar-A's X ray images. Researchers expect to have the instrument in operation at Mees Solar Observatory (Haleakala) in early 1991. They have chosen to use tunable filters as wavelength-selection elements in order to emphasize the spatial relationships between magnetic field elements, and to permit construction of a compact, efficient instrument. This means that spectral information must be obtained from sequences of images, which can cause line profile distortions due to effects of atmospheric seeing.

Peculiarities of the electron energy spectrum in the Coulomb field of a superheavy nucleus

NASA Astrophysics Data System (ADS)

Voronov, B. L.; Gitman, D. M.; Levin, A. D.; Ferreira, R.

2016-05-01

We consider the peculiarities of the electron energy spectrum in the Coulomb field of a superheavy nucleus and discuss the long history of an incorrect interpretation of this problem in the case of a pointlike nucleus and its current correct solution. We consider the spectral problem in the case of a regularized Coulomb potential. For some special regularizations, we derive an exact equation for the point spectrum in the energy interval (-m,m) and find some of its solutions numerically. We also derive an exact equation for charges yielding bound states with the energy E = -m; some call them supercritical charges. We show the existence of an infinite number of such charges. Their existence does not mean that the oneparticle relativistic quantum mechanics based on the Dirac Hamiltonian with the Coulomb field of such charges is mathematically inconsistent, although it is physically unacceptable because the spectrum of the Hamiltonian is unbounded from below. The question of constructing a consistent nonperturbative second-quantized theory remains open, and the consequences of the existence of supercritical charges from the standpoint of the possibility of constructing such a theory also remain unclear.

The formal de Rham complex

NASA Astrophysics Data System (ADS)

Zharinov, V. V.

2013-02-01

We propose a formal construction generalizing the classic de Rham complex to a wide class of models in mathematical physics and analysis. The presentation is divided into a sequence of definitions and elementary, easily verified statements; proofs are therefore given only in the key case. Linear operations are everywhere performed over a fixed number field {F} = {R},{C}. All linear spaces, algebras, and modules, although not stipulated explicitly, are by definition or by construction endowed with natural locally convex topologies, and their morphisms are continuous.

Concept analysis: patient autonomy in a caring context.

PubMed

Lindberg, Catharina; Fagerström, Cecilia; Sivberg, Bengt; Willman, Ania

2014-10-01

This paper is a report of an analysis of the concept of patient autonomy Many problems regarding patient autonomy in healthcare contexts derive from the patient's dependent condition as well as the traditional authoritarian position of healthcare professionals. Existing knowledge and experience reveal a lack of consensus among nurses regarding the meaning of this ethical concept. Concept analysis. Medline, CINAHL, The Cochrane Library and PsycINFO were searched (2005-June 2013) using the search blocks 'autonomy', 'patient' and 'nursing/caring'. A total of 41 articles were retrieved. The Evolutionary Method of Concept Analysis by Rodgers was used to identify and construct the meaning of the concept of patient autonomy in a caring context. Five attributes were identified, thus creating the following descriptive definition: 'Patient autonomy is a gradual, time-changing process of (re-)constructing autonomy through the interplay of to be seen as a person, the capacity to act and the obligation to take responsibility for one's actions'. Patient vulnerability was shown to be the antecedent of patient autonomy and arises due to an impairment of a person's physical and/or mental state. The consequences of patient autonomy were discussed in relation to preserving control and freedom. Patient autonomy in a caring context does not need to be the same before, during and after a care episode. A tentative model has been constructed, thus extending the understanding of this ethical concept in a caring context. © 2014 John Wiley & Sons Ltd.

Refractive collimation beam shaper design and sensitivity analysis using a free-form profile construction method.

PubMed

Tsai, Chung-Yu

2017-07-01

A refractive laser beam shaper comprising two free-form profiles is presented. The profiles are designed using a free-form profile construction method such that each incident ray is directed in a certain user-specified direction or to a particular point on the target surface so as to achieve the required illumination distribution of the output beam. The validity of the proposed design method is demonstrated by means of ZEMAX simulations. The method is mathematically straightforward and easily implemented in computer code. It thus provides a convenient tool for the design and sensitivity analysis of laser beam shapers and similar optical components.

Global-Local Finite Element Analysis for Thermo-Mechanical Stresses in Bonded Joints

NASA Technical Reports Server (NTRS)

Shkarayev, S.; Madenci, Erdogan; Camarda, C. J.

1997-01-01

An analysis of adhesively bonded joints using conventional finite elements does not capture the singular behavior of the stress field in regions where two or three dissimilar materials form a junction with or without free edges. However, these regions are characteristic of the bonded joints and are prone to failure initiation. This study presents a method to capture the singular stress field arising from the geometric and material discontinuities in bonded composites. It is achieved by coupling the local (conventional) elements with global (special) elements whose interpolation functions are constructed from the asymptotic solution.

A comprehensive analysis of the performance characteristics of the Mount Laguna solar photovoltaic installation

NASA Technical Reports Server (NTRS)

Shumka, A.; Sollock, S. G.

1981-01-01

This paper represents the first comprehensive survey of the Mount Laguna Photovoltaic Installation. The novel techniques used for performing the field tests have been effective in locating and characterizing defective modules. A comparative analysis on the two types of modules used in the array indicates that they have significantly different failure rates, different distributions in degradational space and very different failure modes. A life cycle model is presented to explain a multimodal distribution observed for one module type. A statistical model is constructed and it is shown to be in good agreement with the field data.

Modeling of forest canopy BRDF using DIRSIG

NASA Astrophysics Data System (ADS)

Rengarajan, Rajagopalan; Schott, John R.

2016-05-01

The characterization and temporal analysis of multispectral and hyperspectral data to extract the biophysical information of the Earth's surface can be significantly improved by understanding its aniosotropic reflectance properties, which are best described by a Bi-directional Reflectance Distribution Function (BRDF). The advancements in the field of remote sensing techniques and instrumentation have made hyperspectral BRDF measurements in the field possible using sophisticated goniometers. However, natural surfaces such as forest canopies impose limitations on both the data collection techniques, as well as, the range of illumination angles that can be collected from the field. These limitations can be mitigated by measuring BRDF in a virtual environment. This paper presents an approach to model the spectral BRDF of a forest canopy using the Digital Image and Remote Sensing Image Generation (DIRSIG) model. A synthetic forest canopy scene is constructed by modeling the 3D geometries of different tree species using OnyxTree software. The field collected spectra from the Harvard forest is used to represent the optical properties of the tree elements. The canopy radiative transfer is estimated using the DIRSIG model for specific view and illumination angles to generate BRDF measurements. A full hemispherical BRDF is generated by fitting the measured BRDF to a semi-empirical BRDF model. The results from fitting the model to the measurement indicates a root mean square error of less than 5% (2 reflectance units) relative to the forest's reflectance in the VIS-NIR-SWIR region. The process can be easily extended to generate a spectral BRDF library for various biomes.

Evaluation of candidate geomagnetic field models for IGRF-11

NASA Astrophysics Data System (ADS)

Finlay, C. C.; Maus, S.; Beggan, C. D.; Hamoudi, M.; Lowes, F. J.; Olsen, N.; Thébault, E.

2010-10-01

The eleventh generation of the International Geomagnetic Reference Field (IGRF) was agreed in December 2009 by a task force appointed by the International Association of Geomagnetism and Aeronomy (IAGA) Division V Working Group V-MOD. New spherical harmonic main field models for epochs 2005.0 (DGRF-2005) and 2010.0 (IGRF-2010), and predictive linear secular variation for the interval 2010.0-2015.0 (SV-2010-2015) were derived from weighted averages of candidate models submitted by teams led by DTU Space, Denmark (team A); NOAA/NGDC, U.S.A. (team B); BGS, U.K. (team C); IZMIRAN, Russia (team D); EOST, France (team E); IPGP, France (team F); GFZ, Germany (team G) and NASA-GSFC, U.S.A. (team H). Here, we report the evaluations of candidate models carried out by the IGRF-11 task force during October/November 2009 and describe the weightings used to derive the new IGRF-11 model. The evaluations include calculations of root mean square vector field differences between the candidates, comparisons of the power spectra, and degree correlations between the candidates and a mean model. Coefficient by coefficient analysis including determination of weighting factors used in a robust estimation of mean coefficients is also reported. Maps of differences in the vertical field intensity at Earth's surface between the candidates and weighted mean models are presented. Candidates with anomalous aspects are identified and efforts made to pinpoint both troublesome coefficients and geographical regions where large variations between candidates originate. A retrospective analysis of IGRF-10 main field candidates for epoch 2005.0 and predictive secular variation candidates for 2005.0-2010.0 using the new IGRF-11 models as a reference is also reported. The high quality and consistency of main field models derived using vector satellite data is demonstrated; based on internal consistency DGRF-2005 has a formal root mean square vector field error over Earth's surface of 1.0 nT. Difficulties nevertheless remain in accurately forecasting field evolution only five years into the future.

A Systematic Review of Clinical Functional Outcomes After Medial Stabilized Versus Non-Medial Stabilized Total Knee Joint Replacement

PubMed Central

Young, Tony; Dowsey, Michelle M.; Pandy, Marcus; Choong, Peter F.

2018-01-01

Background Medial stabilized total knee joint replacement (TKJR) construct is designed to closely replicate the kinematics of the knee. Little is known regarding comparison of clinical functional outcomes of patients utilising validated patient reported outcome measures (PROM) after medial stabilized TKJR and other construct designs. Purpose To perform a systematic review of the available literature related to the assessment of clinical functional outcomes following a TKJR employing a medial stabilized construct design. Methods The review was performed with a Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) algorithm. The literature search was performed using variouscombinations of keywords. The statistical analysis was completed using Review Manager (RevMan), Version 5.3. Results In the nineteen unique studies identified, there were 2,448 medial stabilized TKJRs implanted in 2,195 participants, there were 1,777 TKJRs with non-medial stabilized design constructs implanted in 1,734 subjects. The final mean Knee Society Score (KSS) value in the medial stabilized group was 89.92 compared to 90.76 in the non-medial stabilized group, with the final KSS mean value difference between the two groups was statistically significant and favored the non-medial stabilized group (SMD 0.21; 95% CI: 0.01 to 0.41; p = 004). The mean difference in the final WOMAC values between the two groups was also statistically significant and favored the medial stabilized group (SMD: −0.27; 95% CI: −0.47 to −0.07; p = 0.009). Moderate to high values (I2) of heterogeneity were observed during the statistical comparison of these functional outcomes. Conclusion Based on the small number of studies with appropriate statistical analysis, we are unable to reach a clear conclusion in the clinical performance of medial stabilized knee replacement construct. Level of Evidence Level II PMID:29696144

A Systematic Review of Clinical Functional Outcomes After Medial Stabilized Versus Non-Medial Stabilized Total Knee Joint Replacement.

PubMed

Young, Tony; Dowsey, Michelle M; Pandy, Marcus; Choong, Peter F

2018-01-01

Medial stabilized total knee joint replacement (TKJR) construct is designed to closely replicate the kinematics of the knee. Little is known regarding comparison of clinical functional outcomes of patients utilising validated patient reported outcome measures (PROM) after medial stabilized TKJR and other construct designs. To perform a systematic review of the available literature related to the assessment of clinical functional outcomes following a TKJR employing a medial stabilized construct design. The review was performed with a Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) algorithm. The literature search was performed using variouscombinations of keywords. The statistical analysis was completed using Review Manager (RevMan), Version 5.3. In the nineteen unique studies identified, there were 2,448 medial stabilized TKJRs implanted in 2,195 participants, there were 1,777 TKJRs with non-medial stabilized design constructs implanted in 1,734 subjects. The final mean Knee Society Score (KSS) value in the medial stabilized group was 89.92 compared to 90.76 in the non-medial stabilized group, with the final KSS mean value difference between the two groups was statistically significant and favored the non-medial stabilized group (SMD 0.21; 95% CI: 0.01 to 0.41; p = 004). The mean difference in the final WOMAC values between the two groups was also statistically significant and favored the medial stabilized group (SMD: -0.27; 95% CI: -0.47 to -0.07; p = 0.009). Moderate to high values ( I 2 ) of heterogeneity were observed during the statistical comparison of these functional outcomes. Based on the small number of studies with appropriate statistical analysis, we are unable to reach a clear conclusion in the clinical performance of medial stabilized knee replacement construct. Level II.

Analysis of Lightning-induced Impulse Magnetic Fields in the Building with an Insulated Down Conductor

NASA Astrophysics Data System (ADS)

Du, Patrick Y.; Zhou, Qi-Bin

This paper presents an analysis of lightning-induced magnetic fields in a building. The building of concern is protected by the lightning protection system with an insulated down conductor. In this paper a system model for metallic structure of the building is constructed first using the circuit approach. The circuit model of the insulated down conductor is discussed extensively, and explicit expressions of the circuit parameters are presented. The system model was verified experimentally in the laboratory. The modeling approach is applied to analyze the impulse magnetic fields in a full-scale building during a direct lightning strike. It is found that the impulse magnetic field is significantly high near the down conductor. The field is attenuated if the down conductor is moved to a column in the building. The field can be reduced further if the down conductor is housed in an earthed metal pipe. Recommendations for protecting critical equipment against lightning-induced magnetic fields are also provided in the paper.

Magnetic-Nozzle Studies for Fusion Propulsion Applications: Gigawatt Plasma Source Operation and Magnetic Nozzle Analysis

NASA Technical Reports Server (NTRS)

Gilland, James H.; Mikekkides, Ioannis; Mikellides, Pavlos; Gregorek, Gerald; Marriott, Darin

2004-01-01

This project has been a multiyear effort to assess the feasibility of a key process inherent to virtually all fusion propulsion concepts: the expansion of a fusion-grade plasma through a diverging magnetic field. Current fusion energy research touches on this process only indirectly through studies of plasma divertors designed to remove the fusion products from a reactor. This project was aimed at directly addressing propulsion system issues, without the expense of constructing a fusion reactor. Instead, the program designed, constructed, and operated a facility suitable for simulating fusion reactor grade edge plasmas, and to examine their expansion in an expanding magnetic nozzle. The approach was to create and accelerate a dense (up to l0(exp 20)/m) plasma, stagnate it in a converging magnetic field to convert kinetic energy to thermal energy, and examine the subsequent expansion of the hot (100's eV) plasma in a subsequent magnetic nozzle. Throughout the project, there has been a parallel effort between theoretical and numerical design and modelling of the experiment and the experiment itself. In particular, the MACH2 code was used to design and predict the performance of the magnetoplasmadynamic (MPD) plasma accelerator, and to design and predict the design and expected behavior for the magnetic field coils that could be added later. Progress to date includes the theoretical accelerator design and construction, development of the power and vacuum systems to accommodate the powers and mass flow rates of interest to out research, operation of the accelerator and comparison to theoretical predictions, and computational analysis of future magnetic field coils and the expected performance of an integrated source-nozzle experiment.

Japanese MAGSAT team

NASA Technical Reports Server (NTRS)

Fukushima, N.; Maeda, H.; Yukutake, T.; Tanaka, M.; Miyazaki, Y.; Oshima, S.; Ogawa, K.; Kawamura, M.; Uyeda, S.; Kobayashi, K.

1982-01-01

Construction of a model of the regional magnetic field and investigation of the local magnetic anomalies and their origin were approaches used in attempts to study the crustal structure near Japan and its Antarctic bases. Spatial properties of the regional magnetic field and comparison of the regional model with that derived from MAGSAT data are discussed. Possible causes of the magnetic anomalies, and results of aeromagnetic surveys incorporating gravity and seismic data are explored. Ionospheric and magnetospheric contributions to geomagnetic variations, field-aligned currents, magnetic geomagnetic pulsations, and hydromagnetic waves by analysis of MAGSAT data are also examined.

Constant fields and constant gradients in open ionic channels.

PubMed Central

Chen, D P; Barcilon, V; Eisenberg, R S

1992-01-01

Ions enter cells through pores in proteins that are holes in dielectrics. The energy of interaction between ion and charge induced on the dielectric is many kT, and so the dielectric properties of channel and pore are important. We describe ionic movement by (three-dimensional) Nemst-Planck equations (including flux and net charge). Potential is described by Poisson's equation in the pore and Laplace's equation in the channel wall, allowing induced but not permanent charge. Asymptotic expansions are constructed exploiting the long narrow shape of the pore and the relatively high dielectric constant of the pore's contents. The resulting one-dimensional equations can be integrated numerically; they can be analyzed when channels are short or long (compared with the Debye length). Traditional constant field equations are derived if the induced charge is small, e.g., if the channel is short or if the total concentration gradient is zero. A constant gradient of concentration is derived if the channel is long. Plots directly comparable to experiments are given of current vs voltage, reversal potential vs. concentration, and slope conductance vs. concentration. This dielectric theory can easily be tested: its parameters can be determined by traditional constant field measurements. The dielectric theory then predicts current-voltage relations quite different from constant field, usually more linear, when gradients of total concentration are imposed. Numerical analysis shows that the interaction of ion and channel can be described by a mean potential if, but only if, the induced charge is negligible, that is to say, the electric field is spatially constant. Images FIGURE 1 PMID:1376159

Mathematization of experience in a grade 8 open-inquiry environment: An introduction to the representational practices of science

NASA Astrophysics Data System (ADS)

Roth, Wolff-Michael; Bowen, G. Michael

The purpose of this classroom study was to investigate the use of mathematical representations in three Grade 8 general science classes that engaged in a 10-week open inquiry about the correlations between biological and physical variables in the environment. A constructivist perspective was used to design the study and to assemble the data sources. These data sources included videotapes of students in their work, audiotapes of teacher-student interactions and teacher interviews, the transcripts of these tapes, the students' field notebooks, field reports, special problem assignments, examinations, and the teachers' curriculum guides, field notes, and reflective journal. An interpretive method was used to construct assertions and the supporting data. In the setting provided, students increasingly used mathematical representations such as graphs and data tables to support their claims in a convincing manner; the use of abstract equations and percent calculations did not change over the course of the study. Representations such as graphs, maps, averages, and equations were not only useful as inscriptions (representations in some permanent medium, usually paper), but also as conscription devices in the construction of, and through which, students engaged each other to collaboratively construct meaning. This study demonstrates the use of representations as conscription devices, and illustrates how the use and understanding of inscriptions changes over time. Understanding representations as inscription and conscription devices focuses on the social aspects of knowing, which has important implications for teachers' conceptualization of learning and their organization of science classrooms.

Construction material properties of slag from the high temperature arc gasification of municipal solid waste.

PubMed

Roessler, Justin G; Olivera, Fernando D; Wasman, Scott J; Townsend, Timothy G; McVay, Michael C; Ferraro, Christopher C; Blaisi, Nawaf I

2016-06-01

Slag from the high temperature arc gasification (HTAG) of municipal solid waste (MSW) was tested to evaluate its material properties with respect to use as a construction aggregate. These data were compared to previously compiled values for waste to energy bottom ash, the most commonly produced and beneficially used thermal treatment residue. The slag was tested using gradations representative of a base course and a course aggregate. Los Angeles (LA) abrasion testing demonstrated that the HTAG slag had a high resistance to fracture with a measured LA loss of 24%. Soundness testing indicated a low potential for reactivity and good weathering resistance with a mean soundness loss of 3.14%. The modified Proctor compaction testing found the slag to possess a maximum dry density (24.04kN/m(3)) greater than conventionally used aggregates and WTE BA. The LBR tests demonstrated a substantial bearing capacity (>200). Mineralogical analysis of the HTAG suggested the potential for self cementing character which supports the elevated LBR results. Preliminary material characterization of the HTAG slag establishes potential for beneficial use; larger and longer term studies focusing on the material's possibility for swelling and performance at the field scale level are needed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Systems antecedents for dissemination and implementation: a review and analysis of measures.

PubMed

Emmons, Karen M; Weiner, Bryan; Fernandez, Maria Eulalia; Tu, Shin-Ping

2012-02-01

There is a growing emphasis on the role of organizations as settings for dissemination and implementation. Only recently has the field begun to consider features of organizations that affect dissemination and implementation of evidence-based interventions. This manuscript identifies and evaluates available measures for five key organizational-level constructs: (a) leadership, (b) vision, (c) managerial relations, (d) climate, and (e) absorptive capacity. Overall the picture was the same across the five constructs--no measure was used in more than one study, many studies did not report the psychometric properties of the measures, some assessments were based on a single response per unit, and the level of the instrument and analysis did not always match. One must seriously consider the development and evaluation of a robust set of measures that will serve as the basis of building the field, allow for comparisons across organizational types and intervention topics, and allow a robust area of dissemination and implementation research to develop.

Perceptual aspects of reproduced sound in car cabin acoustics.

PubMed

Kaplanis, Neofytos; Bech, Søren; Tervo, Sakari; Pätynen, Jukka; Lokki, Tapio; van Waterschoot, Toon; Jensen, Søren Holdt

2017-03-01

An experiment was conducted to determine the perceptual effects of car cabin acoustics on the reproduced sound field. In-car measurements were conducted whilst the cabin's interior was physically modified. The captured sound fields were recreated in the laboratory using a three-dimensional loudspeaker array. A panel of expert assessors followed a rapid sensory analysis protocol, the flash profile, to perceptually characterize and evaluate 12 acoustical conditions of the car cabin using individually elicited attributes. A multivariate analysis revealed the panel's consensus and the identified perceptual constructs. Six perceptual constructs characterize the differences between the acoustical conditions of the cabin, related to bass, ambience, transparency, width and envelopment, brightness, and image focus. The current results indicate the importance of several acoustical properties of a car's interior on the perceived sound qualities. Moreover, they signify the capacity of the applied methodology in assessing spectral and spatial properties of automotive environments in laboratory settings using a time-efficient and flexible protocol.

Scalar Hairy Black Holes in Four Dimensions are Unstable

NASA Astrophysics Data System (ADS)

Ganchev, Bogdan; Santos, Jorge E.

2018-04-01

We present a numerical analysis of the stability properties of the black holes with scalar hair constructed by Herdeiro and Radu. We prove the existence of a novel gauge where the scalar field perturbations decouple from the metric perturbations, and analyze the resulting quasinormal mode spectrum. We find unstable modes with characteristic growth rates which for uniformly small hair are almost identical to those of a massive scalar field on a fixed Kerr background.

Scalar Hairy Black Holes in Four Dimensions are Unstable.

PubMed

Ganchev, Bogdan; Santos, Jorge E

2018-04-27

We present a numerical analysis of the stability properties of the black holes with scalar hair constructed by Herdeiro and Radu. We prove the existence of a novel gauge where the scalar field perturbations decouple from the metric perturbations, and analyze the resulting quasinormal mode spectrum. We find unstable modes with characteristic growth rates which for uniformly small hair are almost identical to those of a massive scalar field on a fixed Kerr background.

Magnetically charged regular black hole in a model of nonlinear electrodynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Meng-Sen, E-mail: mengsenma@gmail.com

2015-11-15

We obtain a magnetically charged regular black hole in general relativity. The source to the Einstein field equations is nonlinear electrodynamic field in a physically reasonable model of nonlinear electrodynamics (NED). “Physically” here means the NED model is constructed on the basis of three conditions: the Maxwell asymptotic in the weak electromagnetic field limit; the presence of vacuum birefringence phenomenon; and satisfying the weak energy condition (WEC). In addition, we analyze the thermodynamic properties of the regular black hole in two ways. According to the usual black hole thermodynamics, we calculate the heat capacity at constant charge, from which wemore » know the smaller black hole is more stable. We also employ the horizon thermodynamics to discuss the thermodynamic quantities, especially the heat capacity at constant pressure.« less

The Relationship of Bureaucratic Structure to School Climate: An Exploratory Factor Analysis of Construct Validity

ERIC Educational Resources Information Center

Lennon, Patricia A.

2010-01-01

This researcher examined the relationship of bureaucratic structure to school climate by means of an exploratory factor analysis of a measure of bureaucracy developed by Hoy and Sweetland (2000) and the four dimensional measure of climate developed by Hoy, Smith, and Sweetland (2002). Since there had been no other empirical studies whose authors…

Evaluating Psychiatric Hospital Admission Decisions for Children in Foster Care: An Optimal Classification Tree Analysis

ERIC Educational Resources Information Center

Snowden, Jessica A.; Leon, Scott C.; Bryant, Fred B.; Lyons, John S.

2007-01-01

This study explored clinical and nonclinical predictors of inpatient hospital admission decisions across a sample of children in foster care over 4 years (N = 13,245). Forty-eight percent of participants were female and the mean age was 13.4 (SD = 3.5 years). Optimal data analysis (Yarnold & Soltysik, 2005) was used to construct a nonlinear…

Measuring attitudes towards suicide: Preliminary evaluation of an attitude towards suicide scale.

PubMed

Cwik, Jan Christopher; Till, Benedikt; Bieda, Angela; Blackwell, Simon E; Walter, Carolin; Teismann, Tobias

2017-01-01

Our study aimed to validate a previously published scale assessing attitudes towards suicide. Factor structure, convergent and discriminant validity, and predictive validity were investigated. Adult German participants (N=503; mean age=24.74years; age range=18-67years) anonymously completed a set of questionnaires. An exploratory factor analysis was conducted, and incongruous items were deleted. Subsequently, scale properties of the reduced scale and its construct validity were analyzed. A confirmatory factor analysis was then conducted in an independent sample (N=266; mean age=28.77years; age range=18-88years) to further confirm the factor structure of the questionnaire. Parallel analysis indicated a three-factor solution, which was also supported by confirmatory factor analysis: right to commit suicide, interpersonal gesture and resilience. The subscales demonstrated acceptable construct and discriminant validity. Cronbach's α for the subscales ranged from 0.67 to 0.83, explaining 49.70% of the total variance. Positive attitudes towards suicide proved to be predictive of suicide risk status, providing preliminary evidence for the utility of the scale. Future studies aiming to reproduce the factor structure in a more heterogeneous sample are warranted. Copyright © 2016 Elsevier Inc. All rights reserved.

"To be a nurse": a professional choice and the construction of identity processes in the 1970s.

PubMed

Teodosio, Sheila Saint-Clair; Padilha, Maria Itayra

2016-06-01

to analyze the factors that influenced the choice for nursing made by graduates from the first class of the Undergraduate Nursing and Obstetrics Course of the Federal University of Rio Grande do Norte in the 1970s and to understand the senses and meanings of being a nurse when choosing this profession. a qualitative socio-historical study was performed, using oral history to collect data. the analysis generated the following categories: "To be a nurse: a professional choice" and "The ideal of being a nurse: senses and meanings". The senses of "being a nurse" are associated with graduates' perspective of this profession and the meanings included the traditional conceptions that have historically affected it. professional choice was influenced by family and work expectations and the nursing course had an effect on the construction of nurses' professional identity.

Constructal thermodynamics combined with infrared experiments to evaluate temperature differences in cells

PubMed Central

Lucia, Umberto; Grazzini, Giuseppe; Montrucchio, Bartolomeo; Grisolia, Giulia; Borchiellini, Romano; Gervino, Gianpiero; Castagnoli, Carlotta; Ponzetto, Antonio; Silvagno, Francesca

2015-01-01

The aim of this work was to evaluate differences in energy flows between normal and immortalized cells when these distinct biological systems are exposed to environmental stimulation. These differences were considered using a constructal thermodynamic approach, and were subsequently verified experimentally. The application of constructal law to cell analysis led to the conclusion that temperature differences between cells with distinct behaviour can be amplified by interaction between cells and external fields. Experimental validation of the principle was carried out on two cellular models exposed to electromagnetic fields. By infrared thermography we were able to assess small changes in heat dissipation measured as a variation in cell internal energy. The experimental data thus obtained are in agreement with the theoretical calculation, because they show a different thermal dispersion pattern when normal and immortalized cells are exposed to electromagnetic fields. By using two methods that support and validate each other, we have demonstrated that the cell/environment interaction can be exploited to enhance cell behavior differences, in particular heat dissipation. We propose infrared thermography as a technique effective in discriminating distinct patterns of thermal dispersion and therefore able to distinguish a normal phenotype from a transformed one. PMID:26100383

Constructal thermodynamics combined with infrared experiments to evaluate temperature differences in cells.

PubMed

Lucia, Umberto; Grazzini, Giuseppe; Montrucchio, Bartolomeo; Grisolia, Giulia; Borchiellini, Romano; Gervino, Gianpiero; Castagnoli, Carlotta; Ponzetto, Antonio; Silvagno, Francesca

2015-06-23

The aim of this work was to evaluate differences in energy flows between normal and immortalized cells when these distinct biological systems are exposed to environmental stimulation. These differences were considered using a constructal thermodynamic approach, and were subsequently verified experimentally. The application of constructal law to cell analysis led to the conclusion that temperature differences between cells with distinct behaviour can be amplified by interaction between cells and external fields. Experimental validation of the principle was carried out on two cellular models exposed to electromagnetic fields. By infrared thermography we were able to assess small changes in heat dissipation measured as a variation in cell internal energy. The experimental data thus obtained are in agreement with the theoretical calculation, because they show a different thermal dispersion pattern when normal and immortalized cells are exposed to electromagnetic fields. By using two methods that support and validate each other, we have demonstrated that the cell/environment interaction can be exploited to enhance cell behavior differences, in particular heat dissipation. We propose infrared thermography as a technique effective in discriminating distinct patterns of thermal dispersion and therefore able to distinguish a normal phenotype from a transformed one.

Assessment of the long-term impacts of PM10 and PM2.5 particles from construction works on surrounding areas.

PubMed

Azarmi, Farhad; Kumar, Prashant; Marsh, Daniel; Fuller, Gary

2016-02-01

Construction activities are common across cities; however, the studies assessing their contribution to airborne PM10 (≤10 μm) and PM2.5 (≤2.5 μm) particles on the surrounding air quality are limited. Herein, we assessed the impact of PM10 and PM2.5 arising from construction works in and around London. Measurements were carried out at 17 different monitoring stations around three construction sites between January 2002 and December 2013. Tapered element oscillating microbalance (TEOM 1400) and OSIRIS (2315) particle monitors were used to measure the PM10 and PM2.5 fractions in the 0.1-10 μm size range along with the ambient meteorological data. The data was analysed using bivariate concentration polar plots and k-means clustering techniques. Daily mean concentrations of PM10 were found to exceed the European Union target limit value of 50 μg m(-3) at 11 monitoring stations but remained within the allowable 35 exceedences per year, except at two monitoring stations. In general, construction works were found to influence the downwind concentrations of PM10 relatively more than PM2.5. Splitting of the data between working (0800-1800 h; local time) and non-working (1800-0800 h) periods showed about 2.2-fold higher concentrations of PM10 during working hours when compared with non-working hours. However, these observations did not allow to conclude that this increase was from the construction site emissions. Together, the polar concentration plots and the k-means cluster analysis applied to a pair of monitoring stations across the construction sites (i.e. one in upwind and the other in downwind) confirmed the contribution of construction sources on the measured concentrations. Furthermore, pairing the monitoring stations downwind of the construction sites showed a logarithmic decrease (with R(2) about 0.9) in the PM10 and PM2.5 concentration with distance. Our findings clearly indicate an impact of construction activities on the nearby downwind areas and a need for developing mitigation measures to limit their escape from the construction sites.

Developing a Psychometric Instrument to Measure Physical Education Teachers' Job Demands and Resources.

PubMed

Zhang, Tan; Chen, Ang

2017-01-01

Based on the job demands-resources model, the study developed and validated an instrument that measures physical education teachers' job demands-resources perception. Expert review established content validity with the average item rating of 3.6/5.0. Construct validity and reliability were determined with a teacher sample ( n = 397). Exploratory factor analysis established a five-dimension construct structure matching the theoretical construct deliberated in the literature. The composite reliability scores for the five dimensions range from .68 to .83. Validity coefficients (intraclass correlational coefficients) are .69 for job resources items and .82 for job demands items. Inter-scale correlational coefficients range from -.32 to .47. Confirmatory factor analysis confirmed the construct validity with high dimensional factor loadings (ranging from .47 to .84 for job resources scale and from .50 to .85 for job demands scale) and adequate model fit indexes (root mean square error of approximation = .06). The instrument provides a tool to measure physical education teachers' perception of their working environment.

Developing a Psychometric Instrument to Measure Physical Education Teachers’ Job Demands and Resources

PubMed Central

Zhang, Tan; Chen, Ang

2017-01-01

Based on the job demands–resources model, the study developed and validated an instrument that measures physical education teachers’ job demands–resources perception. Expert review established content validity with the average item rating of 3.6/5.0. Construct validity and reliability were determined with a teacher sample (n = 397). Exploratory factor analysis established a five-dimension construct structure matching the theoretical construct deliberated in the literature. The composite reliability scores for the five dimensions range from .68 to .83. Validity coefficients (intraclass correlational coefficients) are .69 for job resources items and .82 for job demands items. Inter-scale correlational coefficients range from −.32 to .47. Confirmatory factor analysis confirmed the construct validity with high dimensional factor loadings (ranging from .47 to .84 for job resources scale and from .50 to .85 for job demands scale) and adequate model fit indexes (root mean square error of approximation = .06). The instrument provides a tool to measure physical education teachers’ perception of their working environment. PMID:29200808

Marvelous medicines and dangerous drugs: the representation of prescription medicine in the UK newsprint media.

PubMed

Prosser, Helen

2010-01-01

Using discourse analysis, this study examines the representation of prescription medicines in the UK newsprint media and, specifically, how the meaning and function of medicines are constructed. At the same time, it examines the extent to which the newsprint media represents a resource for health information, and considers how it may encourage or challenge faith in modern medicine and medical authority. As such, it extends analysis around concepts such as the informed patient and examines the representation of patients and doctors and the extent to which patient-doctor identities promoted in the newsprint media reflect a shift away from paternalism to negotiated encounters. Findings show the media constructs a discrete, contradictory, and frequently oversimplified set of characterizations about medicine. Moreover, it discursively constructs realities that justify and sustain medial dominance. Ideological paradigms in discourse assign patients as passive and disempowered while simultaneously privileging "expert" knowledge. This constructs a reality that marginalizes patients' participation in decision-making.

Adapting Controlled-source Coherence Analysis to Dense Array Data in Earthquake Seismology

NASA Astrophysics Data System (ADS)

Schwarz, B.; Sigloch, K.; Nissen-Meyer, T.

2017-12-01

Exploration seismology deals with highly coherent wave fields generated by repeatable controlled sources and recorded by dense receiver arrays, whose geometry is tailored to back-scattered energy normally neglected in earthquake seismology. Owing to these favorable conditions, stacking and coherence analysis are routinely employed to suppress incoherent noise and regularize the data, thereby strongly contributing to the success of subsequent processing steps, including migration for the imaging of back-scattering interfaces or waveform tomography for the inversion of velocity structure. Attempts have been made to utilize wave field coherence on the length scales of passive-source seismology, e.g. for the imaging of transition-zone discontinuities or the core-mantle-boundary using reflected precursors. Results are however often deteriorated due to the sparse station coverage and interference of faint back-scattered with transmitted phases. USArray sampled wave fields generated by earthquake sources at an unprecedented density and similar array deployments are ongoing or planned in Alaska, the Alps and Canada. This makes the local coherence of earthquake data an increasingly valuable resource to exploit.Building on the experience in controlled-source surveys, we aim to extend the well-established concept of beam-forming to the richer toolbox that is nowadays used in seismic exploration. We suggest adapted strategies for local data coherence analysis, where summation is performed with operators that extract the local slope and curvature of wave fronts emerging at the receiver array. Besides estimating wave front properties, we demonstrate that the inherent data summation can also be used to generate virtual station responses at intermediate locations where no actual deployment was performed. Owing to the fact that stacking acts as a directional filter, interfering coherent wave fields can be efficiently separated from each other by means of coherent subtraction. We propose to construct exploration-type trace gathers, systematically investigate the potential to improve the quality and regularity of realistic synthetic earthquake data and present attempts at separating transmitted and back-scattered wave fields for the improved imaging of Earth's large-scale discontinuities.

[Fire behavior of Mongolian oak leaves fuel bed under no-wind and zero-slope conditions. II. Analysis of the factors affecting flame length and residence time and related prediction models].

PubMed

Zhang, Ji-Li; Liu, Bo-Fei; Di, Xue-Ying; Chu, Teng-Fei; Jin, Sen

2012-11-01

Taking fuel moisture content, fuel loading, and fuel bed depth as controlling factors, the fuel beds of Mongolian oak leaves in Maoershan region of Northeast China in field were simulated, and a total of one hundred experimental burnings under no-wind and zero-slope conditions were conducted in laboratory, with the effects of the fuel moisture content, fuel loading, and fuel bed depth on the flame length and its residence time analyzed and the multivariate linear prediction models constructed. The results indicated that fuel moisture content had a significant negative liner correlation with flame length, but less correlation with flame residence time. Both the fuel loading and the fuel bed depth were significantly positively correlated with flame length and its residence time. The interactions of fuel bed depth with fuel moisture content and fuel loading had significant effects on the flame length, while the interactions of fuel moisture content with fuel loading and fuel bed depth affected the flame residence time significantly. The prediction model of flame length had better prediction effect, which could explain 83.3% of variance, with a mean absolute error of 7.8 cm and a mean relative error of 16.2%, while the prediction model of flame residence time was not good enough, which could only explain 54% of variance, with a mean absolute error of 9.2 s and a mean relative error of 18.6%.

An aggregate urine analysis tool to detect acute dehydration.

PubMed

Hahn, Robert G; Waldréus, Nana

2013-08-01

Urine sampling has previously been evaluated for detecting dehydration in young male athletes. The present study investigated whether urine analysis can serve as a measure of dehydration in men and women of a wide age span. Urine sampling and body weight measurement were undertaken before and after recreational physical exercise (median time: 90 min) in 57 volunteers age 17-69 years (mean age: 42). Urine analysis included urine color, osmolality, specific gravity, and creatinine. The volunteers' body weight decreased 1.1% (mean) while they exercised. There were strong correlations between all 4 urinary markers of dehydration (r = .73-.84, p < .001). Researchers constructed a composite dehydration index graded from 1 to 6 based on these markers. This index changed from 2.70 before exercising to 3.55 after exercising, which corresponded to dehydration of 1.0% as given by a preliminary reference curve based on seven previous studies in athletes. Men were slightly dehydrated at baseline (mean: 1.9%) compared with women (mean: 0.7%; p < .001), though age had no influence on the results. A final reference curve that considered both the present results and the 7 previous studies was constructed in which exercise-induced weight loss (x) was predicted by the exponential equation x = 0.20 dehydration index1.86. Urine sampling can be used to estimate weight loss due to dehydration in adults up to age 70. A robust dehydration index based on four indicators reduces the influence of confounders.

Symbols on Formal Groups

NASA Astrophysics Data System (ADS)

Vostokov, S. V.

1982-04-01

The theory of a continuous Steinberg symbol in a local field is generalized to formal commutative groups. For Lubin-Tate groups, a universal symbol is constructed in explicit form, and it is shown that the module of values of an arbitrary symbol imbeds into the group of points of the formal group. By means of this theory of symbols a new approach is given to obtaining an explicit form for the Hilbert norm residue symbol on Lubin-Tate formal groups. Bibliography: 10 titles.

Inflation in anisotropic scalar-tensor theories

NASA Technical Reports Server (NTRS)

Pimentel, Luis O.; Stein-Schabes, Jaime

1988-01-01

The existence of an inflationary phase in anisotropic Scalar-Tensor Theories is investigated by means of a conformal transformation that allows us to rewrite these theories as gravity minimally coupled to a scalar field with a nontrivial potential. The explicit form of the potential is then used and the No Hair Theorem concludes that there is an inflationary phase in all open or flat anisotropic spacetimes in these theories. Several examples are constructed where the effect becomes manifest.

Translations on Eastern Europe Political, Sociological, and Military Affairs No. 1475.

DTIC Science & Technology

1977-11-18

25,975 children , 117 basic 9-year schools with room for 10,798 pupils, 243 young people’s clubs, 239 school cafeterias, 255 gymnasiums, 382 sports...fields, 412 bathing and swimming pools, and 2,265 childrens ’ playgrounds. Self-help projects also accounted for the construction of 386 health care... childrens ’ recreational facilities. As far as the local and town national committees are concerned, this means that they have a responsibility to work

Magnetic fields of green.

PubMed

Branton, Scott; Lile, Lawrence

2011-01-01

By incorporating even the basic elements of a more environmentally friendly, "green"construction and design in an MRI setting can create a safer, more pleasant space for the patients and staff, better images, and operational cost savings. Using building systems that have reduced amounts of steel can decrease construction time, increase thermal insulation, and reduce the weight of the structure meaning less energy required to transport and install. HVAC systems and lighting design can also play a major role in creating a "green"MRI suite. LEED certification places a focus on quality of the built environment, life cycle cost, and a productive indoor environment, as well as impact on the exterior environment. An LEED certified building considers costs and benefits for the lifetime of the building.

Flexible ion conduit for use under rarefied atmospheric conditions

NASA Astrophysics Data System (ADS)

Hars, Gyorgy; Meuzelaar, Henk LC.

1997-09-01

A tubular ion conduit has been constructed, which transports ions by convection by means of a carrier gas. Typical inlet pressures are in the 10-100 Torr range, with outlet pressures as low as 10-3 Torr. The 20-30 cm, 1-2-mm-i.d., capillary tube, made of an electrically insulating material, is surrounded by a specifically configured pair of helical electrodes ("helical dipole"), which are supplied with symmetrical voltages in the tens of volt amplitude and in 1 MHz frequency range. The vibrational average force field generated reduces the tendency of ions to hit the inner wall of the tube. This way ions can be transported with minimal loss. Previously, known ion guides are operated under molecular flow (high vacuum) conditions only, as opposed to the method described here, where the carrier gas enters under viscous flow conditions and exits as molecular flow. In addition, existing ion guides are stiff in contrast to the flexible construction described here, which can be easily and inexpensively manufactured. The ion conduit is expected to have important applications in connecting ambient or near-ambient pressure electrospray ionization or atmospheric pressure ionization type ion sources to mass spectrometers, while reducing pumping requirements, e.g., field portable equipment. Furthermore, the device may provide a means for connecting electron multiplier detectors to near ambient pressure analyzers such as ion mobility spectrometers.

A systematic literature review and meta-analysis: The Theory of Planned Behavior's application to understand and predict nutrition-related behaviors in youth.

PubMed

Riebl, Shaun K; Estabrooks, Paul A; Dunsmore, Julie C; Savla, Jyoti; Frisard, Madlyn I; Dietrich, Andrea M; Peng, Yiming; Zhang, Xiang; Davy, Brenda M

2015-08-01

Efforts to reduce unhealthy dietary intake behaviors in youth are urgently needed. Theory-based interventions can be effective in promoting behavior change; one promising model is the Theory of Planned Behavior (TPB). The aim of this study was to determine, using a systematic literature review, how the TPB has been applied to investigate dietary behaviors, and to evaluate which constructs are associated with dietary behavioral intentions and behaviors in youth. Publications were identified by searching electronic databases, contacting experts in the field, and examining an evolving Internet-based TPB-specific bibliography. Studies including participants aged 2-18years, all TPB constructs discernible and measured with a description of how the variables were assessed and analyzed, were published in English and peer-reviewed journals, and focused on nutrition-related behaviors in youth were identified. Accompanying a descriptive statistical analysis was the calculation of effect sizes where possible, a two-stage meta-analysis, and a quality assessment using tenants from the Consolidated Standards of Reporting Trials (CONSORT) and Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statements. Thirty-four articles, including three intervention studies, were reviewed. The TPB was most often used to evaluate healthy eating and sugary snack and beverage consumption. Attitude had the strongest relationship with dietary behavioral intention (mean r=0.52), while intention was the most common predictor of behavior performance (mean r=0.38; both p<0.001). All three interventions revealed beneficial outcomes when using the TPB (e.g. η(2)=0.51 and ds=0.91, 0.89, and 0.79); extending the Theory with implementation intentions may enhance its effectiveness (e.g. η(2)=0.76). Overall, the TPB may be an effective framework to identify and understand child and adolescent nutrition-related behaviors, allowing for the development of tailored initiatives targeting poor dietary practices in youth. However, support from the literature is primarily from observational studies and a greater effort towards examining these relationships within intervention studies is needed. Copyright © 2015 Elsevier Ltd. All rights reserved.

A statistical spatial power spectrum of the Earth's lithospheric magnetic field

NASA Astrophysics Data System (ADS)

Thébault, E.; Vervelidou, F.

2015-05-01

The magnetic field of the Earth's lithosphere arises from rock magnetization contrasts that were shaped over geological times. The field can be described mathematically in spherical harmonics or with distributions of magnetization. We exploit this dual representation and assume that the lithospheric field is induced by spatially varying susceptibility values within a shell of constant thickness. By introducing a statistical assumption about the power spectrum of the susceptibility, we then derive a statistical expression for the spatial power spectrum of the crustal magnetic field for the spatial scales ranging from 60 to 2500 km. This expression depends on the mean induced magnetization, the thickness of the shell, and a power law exponent for the power spectrum of the susceptibility. We test the relevance of this form with a misfit analysis to the observational NGDC-720 lithospheric magnetic field model power spectrum. This allows us to estimate a mean global apparent induced magnetization value between 0.3 and 0.6 A m-1, a mean magnetic crustal thickness value between 23 and 30 km, and a root mean square for the field value between 190 and 205 nT at 95 per cent. These estimates are in good agreement with independent models of the crustal magnetization and of the seismic crustal thickness. We carry out the same analysis in the continental and oceanic domains separately. We complement the misfit analyses with a Kolmogorov-Smirnov goodness-of-fit test and we conclude that the observed power spectrum can be each time a sample of the statistical one.

Vibrational spectra and ab initio analysis of tert-butyl, trimethylsilyl, and trimethylgermyl derivatives of 3,3-dimethylcyclopropene III. 3,3-Dimethyl-1-(trimethylsilyl)cyclopropene

NASA Astrophysics Data System (ADS)

De Maré, G. R.; Panchenko, Yu. N.; Abramenkov, A. V.; Baird, M. S.; Tverezovsky, V. V.; Nizovtsev, A. V.; Bolesov, I. G.

2003-07-01

The experimental Raman and IR vibrational spectra of 3,3-dimethyl-1-(trimethylsilyl)cyclopropene in the liquid phase were recorded. Total geometry optimisation was carried out at the HF/6-31G* level and the HF/6-31G*//HF/6-31G* force field was computed. This force field was corrected by scale factors determined previously (using Pulay's method) for correction of the HF/6-31G*//HF/6-31G* force fields of 3,3-dimethylbutene-1, 1-methyl-, 1,2-dimethyl-, and 3,3-dimethylcyclopropene. The theoretical vibrational frequencies calculated from the scaled quantum mechanical force field and the theoretical intensities obtained from the quantum mechanical calculation were used to construct predicted spectra and to perform the vibrational analysis of the experimental spectra.

Developing a high-resolution regional atmospheric reanalysis for Australia

NASA Astrophysics Data System (ADS)

White, Christopher; Fox-Hughes, Paul; Su, Chun-Hsu; Jakob, Dörte; Kociuba, Greg; Eisenberg, Nathan; Steinle, Peter; Harris, Rebecca; Corney, Stuart; Love, Peter; Remenyi, Tomas; Chladil, Mark; Bally, John; Bindoff, Nathan

2017-04-01

A dynamically consistent, long-term atmospheric reanalysis can be used to support high-quality assessments of environmental risk and likelihood of extreme events. Most reanalyses are presently based on coarse-scale global systems that are not suitable for regional assessments in fire risk, water and natural resources, amongst others. The Australian Bureau of Meteorology is currently working to close this gap by producing a high-resolution reanalysis over the Australian and New Zealand region to construct a sequence of atmospheric conditions at sub-hourly intervals over the past 25 years from 1990. The Australia reanalysis consists of a convective-scale analysis nested within a 12 km regional-scale reanalysis, which is bounded by a coarse-scale ERA-Interim reanalysis that provides the required boundary and initial conditions. We use an unchanging atmospheric modelling suite based on the UERRA system used at the UK Met Office and the more recent version of the Bureau of Meteorology's operational numerical prediction model used in ACCESS-R (Australian Community Climate and Earth-System Simulator-Regional system). An advanced (4-dimensional variational) data assimilation scheme is used to optimally combine model physics with multiple observations from aircrafts, sondes, surface observations and satellites to create a best estimate of state of the atmosphere over a 6-hour moving window. This analysis is in turn used to drive a higher-resolution (1.5 km) downscaling model over selected subdomains within Australia, currently eastern New South Wales and Tasmania, with the capability to support this anywhere in the Australia-New Zealand domain. The temporal resolution of the gridded analysis fields for both the regional and higher-resolution subdomains are generally one hour, with many fields such as 10 m winds and 2 m temperatures available every 10 minutes. The reanalysis also produces many other variables that include wind, temperature, moisture, pressure, cloud cover, precipitation, evaporation, soil water, and energy fluxes. In this presentation, we report on the implementation of the Australia regional reanalysis and results from first stages of the project, with a focus on the Tasmanian subdomain. An initial benchmarking 1.5 km data set - referred to as the 'Initial Analysis' - has been constructed over the subdomains consisting of regridded and harmonised analysis and short-term forecast fields from the operational ACCESS-C model using the past 5 years (2011-2015) of archived data. Evaluation of the Initial Analysis against surface observations from automatic weather stations indicate changes in model skills over time that may be attributed to changes in NWP and assimilation systems, and model cycling frequency. Preliminary evaluations of the reanalysis across Tasmania and its inter-comparisons with the Initial Analysis and the ERA-Interim reanalysis products will be presented, including some features across the Tasmanian subdomain such as means and extremes of analysed weather variables. Finally, we describe a number of applications across Tasmania of the reanalysis of immediate interest to meteorologists, fire and landscape managers and other members of the emergency management community, including the use of the data to create post-processed fields such as soil dryness, tornados and fire danger indices for forest fire danger risk assessment, including a climatology of Continuous Haines Index.

Resonances in piecewise potentials and Supersymmetric Quantum Mechanics (SUSY-QM) for the construction of optical potentials

NASA Astrophysics Data System (ADS)

Orozco Cortés, Luis Fernando; Fernández García, Nicolás

2014-05-01

A method to obtain the general solution of any constant piecewise potential is presented, this is achieved by means of the analysis of the transfer matrices in each cutoff. The resonance phenomenon together with the supersymmetric quantum mechanics technique allow us to construct a wide family of complex potentials which can be used as theoretical models for optical systems. The method is applied to the particular case for which the potential function has six cutoff points.

The Use Potential of Traditional Building Materials for the Realization of Structures by Modern Methods of Construction

NASA Astrophysics Data System (ADS)

Spišáková, Marcela; Mačková, Daniela

2015-11-01

The sustainable building has taken off in recent years with many investors looking for new and different methods of construction. The traditional building materials can be made out of natural materials, while others can help to lower energy costs of the occupant once built. Regardless of what the goal of the investor is, traditional building materials and their use is on the rise. The submitted paper provides an overview of natural building materials and possible modern building systems using these construction materials. Based on the questionnaire survey is defined the use potential of traditional building materials for the realization of the construction by methods of modern constructions and then are determined the drivers and barriers of traditional materials through using modern methods of construction. Considering the analysis of the achieved results, we can identify the gaps in the construction market in Slovakia and also to assess the perception of potential investors in the field of traditional building materials use, which is the purpose of submitted paper.

Evaluating the potential of 'on-line' constructed wetlands for mitigating pesticide transfers from agricultural land to surface waters

NASA Astrophysics Data System (ADS)

Whelan, Michael; Ramos, Andre; Guymer, Ian; Villa, Raffaella; Jefferson, Bruce

2016-04-01

Pesticides make important contributions to modern agriculture but losses from land to water can present problems for environmental management, particularly in catchments where surface waters are abstracted for drinking water. Where artificial field drains represent a dominant pathway for pesticide transfers, buffer zones provide little mitigation potential. Instead, "on-line" constructed wetlands have been proposed as a potential means of reducing pesticide fluxes in drainage ditches and headwater streams. Here, we evaluate the potential of small free-surface wetlands to reduce pesticide concentrations in surface waters using a combination of field monitoring and numerical modelling. Two small constructed wetland systems in a first order catchment in Cambridgeshire, UK, were monitored over the 2014-2015 winter season. Discharge was measured at several flow control structures and samples were collected every eight hours and analysed for metaldehyde, a commonly-used molluscicide. Metaldehyde is moderately mobile and, like many other compounds, it has been regularly detected at high concentrations in surface water samples in a number of drinking water supply catchments in the UK over the past few years. However, it is unusually difficult to remove via conventional drinking water treatment which makes it particularly problematical for water companies. Metaldehyde losses from the upstream catchment were significant with peak concentrations occurring in the first storm events in early autumn, soon after application. Concentrations and loads appeared to be unaffected by transit through the wetland over a range of flow conditions - probably due to short solute residence times (quantified via several tracing experiments employing rhodamine WT - a fluorescent dye). A dynamic model, based on fugacity concepts, was constructed to describe chemical fate in the wetland system. The model was used to evaluate mitigation potential and management options under field conditions and for a range of different pesticides under alternative flow and wetland dimension scenarios. In agreement with observations, model predictions for metaldehyde losses in the monitored system were negligible. The scenario analysis suggested that, even for pesticides with a relatively short aquatic half life, wetland systems would need to be much larger than those studied here in order to get any appreciable attenuation. Shallow systems have highest potential for promoting losses due to biodegradation, if we assume that most degrading organisms reside in fixed biofilms in the sediment. Sorption is not predicted to represent a significant net sink, except over short time scales in the first runoff event after application.

Focusing behavior of the fractal vector optical fields designed by fractal lattice growth model.

PubMed

Gao, Xu-Zhen; Pan, Yue; Zhao, Meng-Dan; Zhang, Guan-Lin; Zhang, Yu; Tu, Chenghou; Li, Yongnan; Wang, Hui-Tian

2018-01-22

We introduce a general fractal lattice growth model, significantly expanding the application scope of the fractal in the realm of optics. This model can be applied to construct various kinds of fractal "lattices" and then to achieve the design of a great diversity of fractal vector optical fields (F-VOFs) combinating with various "bases". We also experimentally generate the F-VOFs and explore their universal focusing behaviors. Multiple focal spots can be flexibly enginnered, and the optical tweezers experiment validates the simulated tight focusing fields, which means that this model allows the diversity of the focal patterns to flexibly trap and manipulate micrometer-sized particles. Furthermore, the recovery performance of the F-VOFs is also studied when the input fields and spatial frequency spectrum are obstructed, and the results confirm the robustness of the F-VOFs in both focusing and imaging processes, which is very useful in information transmission.

Construction of a genetic map using EST-SSR markers and QTL analysis of major agronomic characters in hexaploid sweet potato (Ipomoea batatas (L.) Lam).

PubMed

Kim, Jin-Hee; Chung, Il Kyung; Kim, Kyung-Min

2017-01-01

The Sweet potato, Ipomoea batatas (L.) Lam, is difficult to study in genetics and genomics because it is a hexaploid. The sweet potato study not have been performed domestically or internationally. In this study was performed to construct genetic map and quantitative trait loci (QTL) analysis. A total of 245 EST-SSR markers were developed, and the map was constructed by using 210 of those markers. The total map length was 1508.1 cM, and the mean distance between markers was 7.2 cM. Fifteen characteristics were investigated for QTLs analysis. According to those, the Four QTLs were identified, and The LOD score was 3.0. Further studies need to develop molecular markers in terms of EST-SSR markers for doing to be capable of efficient breeding. The genetic map created here using EST-SSR markers will facilitate planned breeding of sweet potato cultivars with various desirable traits.

Necessary but Insufficient

PubMed Central

2017-01-01

Abstract Cross-national data production in social science research has increased dramatically in recent decades. Assessing the comparability of data is necessary before drawing substantive conclusions that are based on cross-national data. Researchers assessing data comparability typically use either quantitative methods such as multigroup confirmatory factor analysis or qualitative methods such as online probing. Because both methods have complementary strengths and weaknesses, this study applies both multigroup confirmatory factor analysis and online probing in a mixed-methods approach to assess the comparability of constructive patriotism and nationalism, two important concepts in the study of national identity. Previous measurement invariance tests failed to achieve scalar measurement invariance, which prohibits a cross-national comparison of latent means (Davidov 2009). The arrival of the 2013 ISSP Module on National Identity has encouraged a reassessment of both constructs and a push to understand why scalar invariance cannot be achieved. Using the example of constructive patriotism and nationalism, this study demonstrates how the combination of multigroup confirmatory factor analysis and online probing can uncover and explain issues related to cross-national comparability. PMID:28579643

Research on artificial neural network intrusion detection photochemistry based on the improved wavelet analysis and transformation

NASA Astrophysics Data System (ADS)

Li, Hong; Ding, Xue

2017-03-01

This paper combines wavelet analysis and wavelet transform theory with artificial neural network, through the pretreatment on point feature attributes before in intrusion detection, to make them suitable for improvement of wavelet neural network. The whole intrusion classification model gets the better adaptability, self-learning ability, greatly enhances the wavelet neural network for solving the problem of field detection invasion, reduces storage space, contributes to improve the performance of the constructed neural network, and reduces the training time. Finally the results of the KDDCup99 data set simulation experiment shows that, this method reduces the complexity of constructing wavelet neural network, but also ensures the accuracy of the intrusion classification.

A More Complex Analysis Is Needed.

ERIC Educational Resources Information Center

Lickona, Thomas

1998-01-01

Alfie Kohn's critique of character education in the February 1997 "Kappan" is constructive but not complex enough to provide guidance for the field. Except for briefly describing the Child Development Project, Kohn omits books and articles advocating a comprehensive approach to character education and does not fairly represent some…

An Analysis of Motivation in Three Self-Determination Curricula

ERIC Educational Resources Information Center

Sinclair, James; Bromley, Katherine W.; Shogren, Karrie A.; Murray, Christopher; Unruh, Deanne K.; Harn, Beth A.

2017-01-01

Self-determination skill development is a central construct in the field of secondary special education. Recently, there has been discussion to revisit the motivational theoretical roots that influence the conceptualization of self-determination in special education, and merge motivational theories with instructional practices. Self-determination…

[Emergent topics of educators' perspectives on their own education for retired health care professionals].

PubMed

Lourdes, C; Reus, Velázquez

2002-09-01

The purpose of the study was to explore the nature of seven retired educators' perspectives on their own education. Each educator was from a different health profession. Berger and Luckmann's thesis on the social construction of reality served as the conceptual framework of the study Throughout the study the researcher was able to appreciate that even though the reality of everyday life is a subjective interpretation of the world, there is a continuous correspondence between the researcher's perceptions of meaning and those of others. The in-depth interview method provided an adequate mechanism for the reconstruction of participants' everyday life experiences, and for the construction of categories of meaning. The researcher applied the method of inductive analysis in the identification of the themes and issues and in the construction of the categories. Nine categories of meaning emerged from the participants' reconstruction: 1) the legitimization of retirement; 2) understandings surrounding one's education; 3) understanding of the human aging process; 4) the legitimization of death; 5) the bonds between human beings as a fundamental element of human reality; 6) the roles within, and the objectification of, human activity; 7) the legitimization of religion and the element of spirituality; 8) understandings surrounding one's self; and 9) the reconstruction of the past: traditions and legitimate practices. Within the categories are areas of convergence between the signification of "one's own education" as a modality of life, and the signification of learning and of its propitiatory and restrictive conditions. As to the understandings of meaning and the emergent categories of meaning, the researcher constructed specific educational recommendations, which emphasize the educational processes of the old adult.

Principal semantic components of language and the measurement of meaning.

PubMed

Samsonovich, Alexei V; Samsonovic, Alexei V; Ascoli, Giorgio A

2010-06-11

Metric systems for semantics, or semantic cognitive maps, are allocations of words or other representations in a metric space based on their meaning. Existing methods for semantic mapping, such as Latent Semantic Analysis and Latent Dirichlet Allocation, are based on paradigms involving dissimilarity metrics. They typically do not take into account relations of antonymy and yield a large number of domain-specific semantic dimensions. Here, using a novel self-organization approach, we construct a low-dimensional, context-independent semantic map of natural language that represents simultaneously synonymy and antonymy. Emergent semantics of the map principal components are clearly identifiable: the first three correspond to the meanings of "good/bad" (valence), "calm/excited" (arousal), and "open/closed" (freedom), respectively. The semantic map is sufficiently robust to allow the automated extraction of synonyms and antonyms not originally in the dictionaries used to construct the map and to predict connotation from their coordinates. The map geometric characteristics include a limited number ( approximately 4) of statistically significant dimensions, a bimodal distribution of the first component, increasing kurtosis of subsequent (unimodal) components, and a U-shaped maximum-spread planar projection. Both the semantic content and the main geometric features of the map are consistent between dictionaries (Microsoft Word and Princeton's WordNet), among Western languages (English, French, German, and Spanish), and with previously established psychometric measures. By defining the semantics of its dimensions, the constructed map provides a foundational metric system for the quantitative analysis of word meaning. Language can be viewed as a cumulative product of human experiences. Therefore, the extracted principal semantic dimensions may be useful to characterize the general semantic dimensions of the content of mental states. This is a fundamental step toward a universal metric system for semantics of human experiences, which is necessary for developing a rigorous science of the mind.

Developing the Second Generation CMORPH: A Prototype

NASA Astrophysics Data System (ADS)

Xie, Pingping; Joyce, Robert

2014-05-01

A prototype system of the second generation CMORPH is being developed at NOAA Climate Prediction Center (CPC) to produce global analyses of 30-min precipitation on a 0.05deg lat/lon grid over the entire globe from pole to pole through integration of information from satellite observations as well as numerical model simulations. The second generation CMORPH is built upon the Kalman Filter based CMORPH algorithm of Joyce and Xie (2011). Inputs to the system include rainfall and snowfall rate retrievals from passive microwave (PMW) measurements aboard all available low earth orbit (LEO) satellites, estimates derived from infrared (IR) observations of geostationary (GEO) as well as LEO platforms, and precipitation simulations from numerical global models. First, precipitation estimation / retrievals from various sources are mapped onto a global grid of 0.05deg lat/lon and calibrated against a common reference field to ensure consistency in their precipitation rate PDF structures. The motion vectors for the precipitating cloud systems are then defined using information from both satellite IR observations and precipitation fields generated by the NCEP Climate Forecast System Reanalysis (CFSR). To this end, motion vectors are first computed from CFSR hourly precipitation fields through cross-correlation analysis of consecutive hourly precipitation fields on the global T382 (~35 km) grid. In a similar manner, separate processing is also performed on satellite IR-based precipitation estimates to derive motion vectors from observations. A blended analysis of precipitating cloud motion vectors is then constructed through the combination of CFSR and satellite-derived vectors with an objective analysis technique. Fine resolution mapped PMW precipitation retrievals are then separately propagated along the motion vectors from their respective observation times to the target analysis time from both forward and backward directions. The CMORPH high resolution precipitation analyses are finally constructed through the combination of propagated PMW retrievals with the IR based estimates for the target analysis time. This Kalman Filter based CMORPH processing is performed for rainfall and snowfall fields separately with the same motion vectors. Experiments have been conducted for two periods of two months each, July - August 2009, and January - February 2010, to explore the development of an optimal algorithm that generates global precipitation for summer and winter situations. Preliminary results demonstrated technical feasibility to construct global rainfall and snowfall analyses through the integration of information from multiple sources. More work is underway to refine various technical components of the system for operational applications of the system. Detailed results will be reported at the EGU meeting.

Deviation from the mean in teaching uncertainties

NASA Astrophysics Data System (ADS)

Budini, N.; Giorgi, S.; Sarmiento, L. M.; Cámara, C.; Carreri, R.; Gómez Carrillo, S. C.

2017-07-01

In this work we present two simple and interactive web-based activities for introducing students to the concepts of uncertainties in measurements. These activities are based on the real-time construction of histograms from students measurements and their subsequent analysis through an active and dynamic approach.

33 CFR 148.400 - What does this subpart do?

Code of Federal Regulations, 2011 CFR

2011-07-01

... and other equipment; and (3) Studies done for the preparation of the environmental analysis required... evaluation and pre-construction testing” means studies performed at potential deepwater port locations, including: (1) Preliminary studies to determine the feasibility of a site; (2) Detailed studies of the...

33 CFR 148.400 - What does this subpart do?

Code of Federal Regulations, 2010 CFR

2010-07-01

... and other equipment; and (3) Studies done for the preparation of the environmental analysis required... evaluation and pre-construction testing” means studies performed at potential deepwater port locations, including: (1) Preliminary studies to determine the feasibility of a site; (2) Detailed studies of the...

CFD analysis of a diaphragm free-piston Stirling cryocooler

NASA Astrophysics Data System (ADS)

Caughley, Alan; Sellier, Mathieu; Gschwendtner, Michael; Tucker, Alan

2016-10-01

This paper presents a Computational Fluid Dynamics (CFD) analysis of a novel free-piston Stirling cryocooler that uses a pair of metal diaphragms to seal and suspend the displacer. The diaphragms allow the displacer to move without rubbing or moving seals. When coupled to a metal diaphragm pressure wave generator, the system produces a complete Stirling cryocooler with no rubbing parts in the working gas space. Initial modelling of this concept using the Sage modelling tool indicated the potential for a useful cryocooler. A proof-of-concept prototype was constructed and achieved cryogenic temperatures. A second prototype was designed and constructed using the experience gained from the first. The prototype produced 29 W of cooling at 77 K and reached a no-load temperature of 56 K. The diaphragm's large diameter and short stroke produces a significant radial component to the oscillating flow fields inside the cryocooler which were not modelled in the one-dimensional analysis tool Sage that was used to design the prototypes. Compared with standard pistons, the diaphragm geometry increases the gas-to-wall heat transfer due to the higher velocities and smaller hydraulic diameters. A Computational Fluid Dynamics (CFD) model of the cryocooler was constructed to understand the underlying fluid-dynamics and heat transfer mechanisms with the aim of further improving performance. The CFD modelling of the heat transfer in the radial flow fields created by the diaphragms shows the possibility of utilizing the flat geometry for heat transfer, reducing the need for, and the size of, expensive heat exchangers. This paper presents details of a CFD analysis used to model the flow and gas-to-wall heat transfer inside the second prototype cryocooler, including experimental validation of the CFD to produce a robust analysis.

PROBLEMS AND METHODOLOGY OF THE PETROLOGIC ANALYSIS OF COAL FACIES.

USGS Publications Warehouse

Chao, Edward C.T.

1983-01-01

This condensed synthesis gives a broad outline of the methodology of coal facies analysis, procedures for constructing sedimentation and geochemical formation curves, and micro- and macrostratigraphic analysis. The hypothetical coal bed profile has a 3-fold cycle of material characteristics. Based on studies of other similar profiles of the same coal bed, and on field studies of the sedimentary rock types and their facies interpretation, one can assume that the 3-fold subdivision is of regional significance.

Analytical slave-spin mean-field approach to orbital selective Mott insulators

NASA Astrophysics Data System (ADS)

Komijani, Yashar; Kotliar, Gabriel

2017-09-01

We use the slave-spin mean-field approach to study particle-hole symmetric one- and two-band Hubbard models in the presence of Hund's coupling interaction. By analytical analysis of the Hamiltonian, we show that the locking of the two orbitals vs orbital selective Mott transition can be formulated within a Landau-Ginzburg framework. By applying the slave-spin mean field to impurity problems, we are able to make a correspondence between impurity and lattice. We also consider the stability of the orbital selective Mott phase to the hybridization between the orbitals and study the limitations of the slave-spin method for treating interorbital tunnelings in the case of multiorbital Bethe lattices with particle-hole symmetry.

High order volume-preserving algorithms for relativistic charged particles in general electromagnetic fields

NASA Astrophysics Data System (ADS)

He, Yang; Sun, Yajuan; Zhang, Ruili; Wang, Yulei; Liu, Jian; Qin, Hong

2016-09-01

We construct high order symmetric volume-preserving methods for the relativistic dynamics of a charged particle by the splitting technique with processing. By expanding the phase space to include the time t, we give a more general construction of volume-preserving methods that can be applied to systems with time-dependent electromagnetic fields. The newly derived methods provide numerical solutions with good accuracy and conservative properties over long time of simulation. Furthermore, because of the use of an accuracy-enhancing processing technique, the explicit methods obtain high-order accuracy and are more efficient than the methods derived from standard compositions. The results are verified by the numerical experiments. Linear stability analysis of the methods shows that the high order processed method allows larger time step size in numerical integrations.

Occupational risk assessment in the construction industry in Iran.

PubMed

Seifi Azad Mard, Hamid Reza; Estiri, Ali; Hadadi, Parinaz; Seifi Azad Mard, Mahshid

2017-12-01

Occupational accidents in the construction industry are more common compared with other fields and these accidents are more severe compared with the global average in developing countries, especially in Iran. Studies which lead to the source of these accidents and suggest solutions for them are therefore valuable. In this study a combination of the failure mode and effects analysis method and fuzzy theory is used as a semi-qualitative-quantitative method for analyzing risks and failure modes. The main causes of occupational accidents in this field were identified and analyzed based on three factors; severity, detection and occurrence. Based on whether the risks are high or low priority, modifying actions were suggested to reduce the occupational risks. Finally, the results showed that high priority risks had a 40% decrease due to these actions.

Wavelet synthetic method for turbulent flow.

PubMed

Zhou, Long; Rauh, Cornelia; Delgado, Antonio

2015-07-01

Based on the idea of random cascades on wavelet dyadic trees and the energy cascade model known as the wavelet p model, a series of velocity increments in two-dimensional space are constructed in different levels of scale. The dynamics is imposed on the generated scales by solving the Euler equation in the Lagrangian framework. A dissipation model is used in order to cover the shortage of the p model, which only predicts in inertial range. Wavelet reconstruction as well as the multiresolution analysis are then performed on each scales. As a result, a type of isotropic velocity field is created. The statistical properties show that the constructed velocity fields share many important features with real turbulence. The pertinence of this approach in the prediction of flow intermittency is also discussed.

Fall-Related Psychological Concerns and Anxiety among Community-Dwelling Older Adults: Systematic Review and Meta-Analysis

PubMed Central

Payette, Marie-Christine; Bélanger, Claude; Léveillé, Vanessa; Grenier, Sébastien

2016-01-01

Fear of falling and other fall-related psychological concerns (FRPCs), such as falls-efficacy and balance confidence, are highly prevalent among community-dwelling older adults. Anxiety and FRPCs have frequently, but inconsistently, been found to be associated in the literature. The purpose of this study is to clarify those inconsistencies with a systematic review and meta-analysis and to evaluate if the strength of this relationship varies based on the different FRPC constructs used (e.g., fear of falling, falls-efficacy or balance confidence). A systematic review was conducted through multiple databases (e.g., MEDLINE, PsycINFO) to include all articles published before June 10th 2015 that measured anxiety and FRPCs in community-dwelling older adults. Active researchers in the field were also contacted in an effort to include unpublished studies. The systematic review led to the inclusion of twenty relevant articles (n = 4738). A random-effect meta-analysis revealed that the mean effect size for fear of falling and anxiety is r = 0.32 (95% CI: 0.22–0.40), Z = 6.49, p < 0.001 and the mean effect size for falls-efficacy or balance confidence and anxiety is r = 0.31 (95% CI: 0.23–0.40), Z = 6.72, p < 0.001. A Q-test for heterogeneity revealed that the two effect sizes are not significantly different (Q(19) = 0.13, p = n.s.). This study is the first meta-analysis on the relationship between anxiety and FRPCs among community-dwelling older adults. It demonstrates the importance of considering anxiety when treating older adults with FRPCs. PMID:27043139

Including sheath effects in the interpretation of planar retarding potential analyzer's low-energy ion data

NASA Astrophysics Data System (ADS)

Fisher, L. E.; Lynch, K. A.; Fernandes, P. A.; Bekkeng, T. A.; Moen, J.; Zettergren, M.; Miceli, R. J.; Powell, S.; Lessard, M. R.; Horak, P.

2016-04-01

The interpretation of planar retarding potential analyzers (RPA) during ionospheric sounding rocket missions requires modeling the thick 3D plasma sheath. This paper overviews the theory of RPAs with an emphasis placed on the impact of the sheath on current-voltage (I-V) curves. It then describes the Petite Ion Probe (PIP) which has been designed to function in this difficult regime. The data analysis procedure for this instrument is discussed in detail. Data analysis begins by modeling the sheath with the Spacecraft Plasma Interaction System (SPIS), a particle-in-cell code. Test particles are traced through the sheath and detector to determine the detector's response. A training set is constructed from these simulated curves for a support vector regression analysis which relates the properties of the I-V curve to the properties of the plasma. The first in situ use of the PIPs occurred during the MICA sounding rocket mission which launched from Poker Flat, Alaska in February of 2012. These data are presented as a case study, providing valuable cross-instrument comparisons. A heritage top-hat thermal ion electrostatic analyzer, called the HT, and a multi-needle Langmuir probe have been used to validate both the PIPs and the data analysis method. Compared to the HT, the PIP ion temperature measurements agree with a root-mean-square error of 0.023 eV. These two instruments agree on the parallel-to-B plasma flow velocity with a root-mean-square error of 130 m/s. The PIP with its field of view aligned perpendicular-to-B provided a density measurement with an 11% error compared to the multi-needle Langmuir Probe. Higher error in the other PIP's density measurement is likely due to simplifications in the SPIS model geometry.

Low-frequency acousto-optic backscattering of Bessel light beams

NASA Astrophysics Data System (ADS)

Khilo, Nikolai A.; Belyi, Vladimir N.; Khilo, Petr A.; Kazak, Nikolai S.

2018-05-01

The use of Bessel light beams, as well as Bessel acoustic beams, substantially enhances the capabilities of acousto-optic methods for control of optical field. We present a theoretical study of the process of optical Bessel beams conversion by means of backward acousto-optic scattering on a Bessel acoustic field in a transversely isotropic crystal. It is shown that, with an appropriate choice of Bessel beams parameters, the backscattering in visible spectral range can be realized at relatively low acoustic frequencies less than one gigahertz. Under conditions of phase matching and transverse spatial synchronism, the efficiency of backscattering is sufficiently high, which is interesting, for example, for construction of acousto-optic spectral analyzers.