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Sample records for models theory fiske

  1. Intertextuality and John Fiske's Viewpoint on Reception-theory of TV Text%论“文本间性”思想与约翰·费斯克电视文本接受观

    Institute of Scientific and Technical Information of China (English)

    李鹏

    2012-01-01

    "Intertextuality" is an important analysis method in television text reception researches used by John Fiske, the United States television cultural scholar. In the view of text theory, this paper analyzes the origin, content and development process of intertextuality theory, and interprets its application in John Fiske's TV text reception-theory. Finally, this paper reviews the influence and limitation of John Fiske's TV text reception-theory.%“文本间性”思想是美国电视文化研究学者约翰·费斯克进行电视文本接受研究的核心理论分析工具之…。本文拟结合文本理论,对这一重要思想的历史渊源、内容涵义及发展过程等因素进行梳理,并在此基础上分析和阐释其在约翰-费斯克电视文本接受研究中的实际应用,最后对这一思想之于电视文本接受研究的理论影响和局限性进行分析评介。

  2. Fremtidens alternativer til soja og fisk

    DEFF Research Database (Denmark)

    Nørgaard, Jan Værum

    2015-01-01

    af verdenen er der også enighed om, at landbrugsjord på bekostning af for eksempel rydning af regnskov i Sydamerika ikke er vejen frem for at producere soja til vores dyr. Mange mener også, at fisk, fanget med det formål at bruge dem som dyrefoder, ikke er en bæredygtig måde at producere kød på...

  3. Model theory

    CERN Document Server

    Chang, CC

    2012-01-01

    Model theory deals with a branch of mathematical logic showing connections between a formal language and its interpretations or models. This is the first and most successful textbook in logical model theory. Extensively updated and corrected in 1990 to accommodate developments in model theoretic methods - including classification theory and nonstandard analysis - the third edition added entirely new sections, exercises, and references. Each chapter introduces an individual method and discusses specific applications. Basic methods of constructing models include constants, elementary chains, Sko

  4. Model theory

    CERN Document Server

    Hodges, Wilfrid

    1993-01-01

    An up-to-date and integrated introduction to model theory, designed to be used for graduate courses (for students who are familiar with first-order logic), and as a reference for more experienced logicians and mathematicians.

  5. On some questions of Fisk and Br\\"and\\'en

    CERN Document Server

    Yoshida, Rintaro

    2010-01-01

    P. Br\\"and\\'en recently proved a conjecture due to S. Fisk, R. P. Stanley, P. R. W. McNamara and B. E. Sagan. In addition, P. Br\\"and\\'en gave a partial answer to a question posed by S. Fisk regarding the distribution of zeros of polynomials under the action of certain non-linear operators. In this paper, we give an extension to a result of P. Br\\"and\\'en, and we also answer a question posed by S. Fisk.

  6. Model Theory and Applications

    CERN Document Server

    Mangani, P

    2011-01-01

    This title includes: Lectures - G.E. Sacks - Model theory and applications, and H.J. Keisler - Constructions in model theory; and, Seminars - M. Servi - SH formulas and generalized exponential, and J.A. Makowski - Topological model theory.

  7. RevFisk – et projekt som kvantificerer stenrevs (et lavtliggende stenrev i den fotiske zone og et dybere liggende stenrev i den afotiske zone) betydning for fisk

    DEFF Research Database (Denmark)

    Stenberg, Claus; Christoffersen, Mads; Aarestrup, Kim;

    . Det er derfor i dag ikke muligt kvantitativt at redegøre for stenrevs betydning for fiskeressourcerne eller udarbejde målrettede natur-genopretningsplaner for stenrev med det formål at genskabe gyde- og opvækstområder for fisk. Det vil Projektet RevFisk forsøge at råde bod på. Centrale spørgsmål i...

  8. RevFisk - et projekt som kvantificerer stenrevs (et lavtliggende stenrev i den fotiske zone og et dybereliggende stenrev i den afotiske zone) betydning for fisk

    DEFF Research Database (Denmark)

    Stenberg, Claus; Christoffersen, Mads; Aastrup, Kim;

    . Det er derfor i dag ikke muligt kvantitativt at redegøre for stenrevs betydning for fiskeressourcerne eller udarbejde målrettede natur-genopretningsplaner for stenrev med det formål at genskabe gyde- og opvækstområder for fisk. Det vil Projektet RevFisk forsøge at råde bod på. Centrale spørgsmål i...

  9. Model theory and applications

    CERN Document Server

    Belegradek, OV

    1999-01-01

    This volume is a collection of papers on model theory and its applications. The longest paper, "Model Theory of Unitriangular Groups" by O. V. Belegradek, forms a subtle general theory behind Mal‴tsev's famous correspondence between rings and groups. This is the first published paper on the topic. Given the present model-theoretic interest in algebraic groups, Belegradek's work is of particular interest to logicians and algebraists. The rest of the collection consists of papers on various questions of model theory, mainly on stability theory. Contributors are leading Russian researchers in the

  10. Model theory and modules

    CERN Document Server

    Prest, M

    1988-01-01

    In recent years the interplay between model theory and other branches of mathematics has led to many deep and intriguing results. In this, the first book on the topic, the theme is the interplay between model theory and the theory of modules. The book is intended to be a self-contained introduction to the subject and introduces the requisite model theory and module theory as it is needed. Dr Prest develops the basic ideas concerning what can be said about modules using the information which may be expressed in a first-order language. Later chapters discuss stability-theoretic aspects of module

  11. Research and education at the NASA Fisk University Center for Photonic Materials and Devices

    Science.gov (United States)

    Silberman, Enrique

    1996-07-01

    In 1992, NASA awarded Fisk University a 5 year grant to establish a center for research and education on photonic materials are synthesized, characterized and, in some cases, developed into devices with applications in the fields of radiation detectors and nonlinear optical crystals, glasses and nanomaterials. The educational components include participation in the research by 3 types of students majoring in Physics, Chemistry and Biology: 1) Fisk undergraduates participating during the academic year. 2) Fisk graduates performing their Maser Thesis research. 3) Fisk and other HBCU's and Minority Institutions' undergraduates attending a 10 week summer workshop with a very rigorous program of study, research and progress reporting. Funds are available for supporting participating students. Prerequisite, schedules of activities, evaluation procedures and typical examples of the outcome are presented.

  12. Theory Modeling and Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Shlachter, Jack [Los Alamos National Laboratory

    2012-08-23

    Los Alamos has a long history in theory, modeling and simulation. We focus on multidisciplinary teams that tackle complex problems. Theory, modeling and simulation are tools to solve problems just like an NMR spectrometer, a gas chromatograph or an electron microscope. Problems should be used to define the theoretical tools needed and not the other way around. Best results occur when theory and experiments are working together in a team.

  13. Fisk-Gloeckler Suprathermal Proton Spectrum in the Heliosheath and the Local Interstellar Medium

    Science.gov (United States)

    Cooper, John F.; Kasprzak, W. T.; Mahaffy, P. R.; Niemann, H. B.; Hartle, R. E.; Paschalidis, N.; Chornay, D.; Coplan, M.; Johnson, R. E.

    2010-01-01

    Convergence of suprathermal keV-MeV proton and ion spectra approximately to the Fisk-Gloeckler (F-G) form j(E) = j(sub 0) E(sup -1.5) in Voyager land 2 heliosheath measurements is suggestive of distributed acceleration in Kolmogorov turbulence which may extend well beyond the heliopause into the local interstellar medium (LISM). Turbulence of this type is already indicated by interstellar radio scintillation measurements of electron density power spectra. Previously published extrapolations (Cooper et al., 2003, 2006) of the LISM proton spectrum from eV to GeV energies are highly consistent with the F-G power-law and further indicative of such turbulence and LISM effectiveness of the F-G cascade acceleration process. The LISM pressure computed from this spectrum well exceeds that from current estimates for the LISM magnetic field, so exchange of energy between the protons and the magnetic field would likely have a strong role in evolution of the turbulence as per the F-G theory and as long ago proposed for cosmic ray energies by Parker and others. Pressure-dependent estimates of the LISM field strength should not ignore this potentially strong and even dominant contribution from the plasma. Presence of high-beta suprathermal plasma on LISM field lines could significantly affect interactions with the heliospheric outer boundary region and might potentially account for distributed and more discrete features in ongoing measurements of energetic neutral emission from the Interstellar Boundary Explorer (IBEX) mission.

  14. Calibration of FISK, an invasiveness screening tool for nonnative freshwater fishes.

    Science.gov (United States)

    Copp, Gordon H; Vilizzi, Lorenzo; Mumford, John; Fenwick, Gemma V; Godard, Michael J; Gozlan, Rodolphe E

    2009-03-01

    Adapted from the weed risk assessment (WRA) of Pheloung, Williams, and Halloy, the fish invasiveness scoring kit (FISK) was proposed as a screening tool for freshwater fishes. This article describes improvements to FISK, in particular the incorporation of confidence (certainty/uncertainty) ranking of the assessors' responses, and reports on the calibration of the score system, specifically: determination of most appropriate score thresholds for classifying nonnative species into low-, medium-, and high-risk categories, assessment of the patterns of assessors' confidences in their responses in the FISK assessments. Using receiver operating characteristic (ROC) curves, FISK was demonstrated to distinguish accurately (and with statistical confidence) between potentially invasive and noninvasive species of nonnative fishes, with the statistically appropriate threshold score for high-risk species scores being >/=19. Within the group of species classed as high risk using this new threshold, a "higher risk" category could be visually identified, at present consisting of two species (topmouth gudgeon Pseudorasbora parva and gibel carp Carassius gibelio). FISK represents a useful and viable tool to aid decision- and policymakers in assessing and classifying freshwater fishes according to their potential invasiveness.

  15. The relationship between relational models and individualism and collectivism: evidence from culturally diverse work groups.

    Science.gov (United States)

    Vodosek, Markus

    2009-04-01

    Relational models theory (Fiske, 1991 ) proposes that all thinking about social relationships is based on four elementary mental models: communal sharing, authority ranking, equality matching, and market pricing. Triandis and his colleagues (e.g., Triandis, Kurowski, & Gelfand, 1994 ) have suggested a relationship between the constructs of horizontal and vertical individualism and collectivism and Fiske's relational models. However, no previous research has examined this proposed relationship empirically. The objective of the current study was to test the association between the two frameworks in order to further our understanding of why members of culturally diverse groups may prefer different relational models in interactions with other group members. Findings from this study support a relationship between Triandis' constructs and Fiske's four relational models and uphold Fiske's ( 1991 ) claim that the use of the relational models is culturally dependent. As hypothesized, horizontal collectivism was associated with a preference for equality matching and communal sharing, vertical individualism was related to a preference for authority ranking, and vertical collectivism was related to a preference for authority ranking and communal sharing. However, contrary to expectations, horizontal individualism was not related to a preference for equality matching and market pricing, and vertical individualism was not associated with market pricing. By showing that there is a relationship between Triandis' and Fiske's frameworks, this study closes a gap in relational models theory, namely how culture relates to people's preferences for relational models. Thus, the findings from this study will enable future researchers to explain and predict what relational models are likely to be used in a certain cultural context.

  16. Subharmonic generation in Josephson junction fluxon oscillators biased on Fiske steps

    DEFF Research Database (Denmark)

    Sørensen, Mads Peter; Christiansen, Peter Leth; Parmentier, R. D.

    1983-01-01

    Numerical integration of the perturbed sine-Gordon equation describing a long overlap-geometry Josephson junction in a magnetic field indicates a branched structure of the first Fiske step. The major portion of the step corresponds to a simply periodic fluxon oscillation whereas the branches...... are characterized by subharmonic generation. Applied Physics Letters is copyrighted by The American Institute of Physics....

  17. Teaching Students About Stereotypes, Prejudice, and Discrimination: An Interview with Susan Fiske

    Science.gov (United States)

    Hackney, Amy

    2005-01-01

    Susan T. Fiske is professor of psychology, Princeton University (PhD, Harvard University; honorary doctorate, Universite Catholique de Louvain-la-Neuve, Belgium). She wrote Social Cognition (with Taylor) on how people make sense of each other. Currently, she investigates emotional prejudices (pity, contempt, envy, and pride) at cultural,…

  18. Noncommutative Gauge Theories: Model for Hodge theory

    CERN Document Server

    Upadhyay, Sudhaker

    2013-01-01

    The nilpotent BRST, anti-BRST, dual-BRST and anti-dual-BRST symmetry transformations are constructed in the context of noncommutative (NC) 1-form as well as 2-form gauge theories. The corresponding Noether's charges for these symmetries on the Moyal plane are shown to satisfy the same algebra as by the de Rham cohomological operators of differential geometry. The Hodge decomposition theorem on compact manifold is also studied. We show that noncommutative gauge theories are field theoretic models for Hodge theory.

  19. Probability state modeling theory.

    Science.gov (United States)

    Bagwell, C Bruce; Hunsberger, Benjamin C; Herbert, Donald J; Munson, Mark E; Hill, Beth L; Bray, Chris M; Preffer, Frederic I

    2015-07-01

    As the technology of cytometry matures, there is mounting pressure to address two major issues with data analyses. The first issue is to develop new analysis methods for high-dimensional data that can directly reveal and quantify important characteristics associated with complex cellular biology. The other issue is to replace subjective and inaccurate gating with automated methods that objectively define subpopulations and account for population overlap due to measurement uncertainty. Probability state modeling (PSM) is a technique that addresses both of these issues. The theory and important algorithms associated with PSM are presented along with simple examples and general strategies for autonomous analyses. PSM is leveraged to better understand B-cell ontogeny in bone marrow in a companion Cytometry Part B manuscript. Three short relevant videos are available in the online supporting information for both of these papers. PSM avoids the dimensionality barrier normally associated with high-dimensionality modeling by using broadened quantile functions instead of frequency functions to represent the modulation of cellular epitopes as cells differentiate. Since modeling programs ultimately minimize or maximize one or more objective functions, they are particularly amenable to automation and, therefore, represent a viable alternative to subjective and inaccurate gating approaches.

  20. Alliance for Computational Science Collaboration HBCU Partnership at Fisk University. Final Report 2001

    Energy Technology Data Exchange (ETDEWEB)

    Collins, W. E.

    2004-08-16

    Computational Science plays a big role in research and development in mathematics, science, engineering and biomedical disciplines. The Alliance for Computational Science Collaboration (ACSC) has the goal of training African-American and other minority scientists in the computational science field for eventual employment with the Department of Energy (DOE). The involvements of Historically Black Colleges and Universities (HBCU) in the Alliance provide avenues for producing future DOE African-American scientists. Fisk University has been participating in this program through grants from the DOE. The DOE grant supported computational science activities at Fisk University. The research areas included energy related projects, distributed computing, visualization of scientific systems and biomedical computing. Students' involvement in computational science research included undergraduate summer research at Oak Ridge National Lab, on-campus research involving the participation of undergraduates, participation of undergraduate and faculty members in workshops, and mentoring of students. These activities enhanced research and education in computational science, thereby adding to Fisk University's spectrum of research and educational capabilities. Among the successes of the computational science activities are the acceptance of three undergraduate students to graduate schools with full scholarships beginning fall 2002 (one for master degree program and two for Doctoral degree program).

  1. Evaluation Theory, Models, and Applications

    Science.gov (United States)

    Stufflebeam, Daniel L.; Shinkfield, Anthony J.

    2007-01-01

    "Evaluation Theory, Models, and Applications" is designed for evaluators and students who need to develop a commanding knowledge of the evaluation field: its history, theory and standards, models and approaches, procedures, and inclusion of personnel as well as program evaluation. This important book shows how to choose from a growing…

  2. Model Theory in Algebra, Analysis and Arithmetic

    CERN Document Server

    Dries, Lou; Macpherson, H Dugald; Pillay, Anand; Toffalori, Carlo; Wilkie, Alex J

    2014-01-01

    Presenting recent developments and applications, the book focuses on four main topics in current model theory: 1) the model theory of valued fields; 2) undecidability in arithmetic; 3) NIP theories; and 4) the model theory of real and complex exponentiation. Young researchers in model theory will particularly benefit from the book, as will more senior researchers in other branches of mathematics.

  3. Fisk - Pesce

    DEFF Research Database (Denmark)

    Fisker, Anna Marie

    2011-01-01

    Nyhedsfolder om deltagelse i den. 54. Kunstbiennale i Venedig udgivet ifm. Cordon Bleu du Saint Esprit Soirée i Innsbruck-Igla, September 2011. "Venice, Italy vs. Hirtshals, Denmark. An adventure with a 1.000 of Fishes, his Royal Highness the Danish Crown Prince Frederik and 28 students from Aalb...... Aalborg University at the 54. International Art Biennale in Venice."......Nyhedsfolder om deltagelse i den. 54. Kunstbiennale i Venedig udgivet ifm. Cordon Bleu du Saint Esprit Soirée i Innsbruck-Igla, September 2011. "Venice, Italy vs. Hirtshals, Denmark. An adventure with a 1.000 of Fishes, his Royal Highness the Danish Crown Prince Frederik and 28 students from...

  4. Stochastic Climate Theory and Modelling

    CERN Document Server

    Franzke, Christian L E; Berner, Judith; Williams, Paul D; Lucarini, Valerio

    2014-01-01

    Stochastic methods are a crucial area in contemporary climate research and are increasingly being used in comprehensive weather and climate prediction models as well as reduced order climate models. Stochastic methods are used as subgrid-scale parameterizations as well as for model error representation, uncertainty quantification, data assimilation and ensemble prediction. The need to use stochastic approaches in weather and climate models arises because we still cannot resolve all necessary processes and scales in comprehensive numerical weather and climate prediction models. In many practical applications one is mainly interested in the largest and potentially predictable scales and not necessarily in the small and fast scales. For instance, reduced order models can simulate and predict large scale modes. Statistical mechanics and dynamical systems theory suggest that in reduced order models the impact of unresolved degrees of freedom can be represented by suitable combinations of deterministic and stochast...

  5. Model companions of theories with an automorphism

    OpenAIRE

    Kikyo, Hirotaka

    1998-01-01

    For a theory $T$ in $L, T_\\sigma$ is the theory of the models of $T$ with an automorphism $\\sigma$. If $T$ is an unstable model complete theory without the independence property, then $T_\\sigma$ has no model companion. If $T$ is an unstable model complete theory and $T_\\sigma$ has the amalgamation property, then $T_\\sigma$ has no model companion. If $T$ is model complete and has the fcp, then $T_\\sigma$ has no model completion.

  6. Models in theory building: the case of early string theory

    Energy Technology Data Exchange (ETDEWEB)

    Castellani, Elena [Department of Philosophy, Florence (Italy)

    2013-07-01

    The history of the origins and first steps of string theory, from Veneziano's formulation of his famous scattering amplitude in 1968 to the 'first string revolution' in 1984, provides rich material for discussing traditional issues in the philosophy of science. This paper focusses on the initial phase of this history, that is the making of early string theory out of the 'dual theory of strong interactions' motivated by the aim of finding a viable theory of hadrons in the framework of the so-called S-matrix theory of the Sixties: from the first two models proposed (the Dual Resonance Model and the Shapiro-Virasoro Model) to all the subsequent endeavours to extend and complete the theory, including its string interpretation. As is the aim of this paper to show, by representing an exemplary illustration of the building of a scientific theory out of tentative and partial models this is a particularly fruitful case study for the current philosophical discussion on how to characterize a scientific model, a scientific theory, and the relation between models and theories.

  7. Models in cooperative game theory

    CERN Document Server

    Branzei, Rodica; Tijs, Stef

    2008-01-01

    This book investigates models in cooperative game theory in which the players have the possibility to cooperate partially. In a crisp game the agents are either fully involved or not involved at all in cooperation with some other agents, while in a fuzzy game players are allowed to cooperate with infinite many different participation levels, varying from non-cooperation to full cooperation. A multi-choice game describes the intermediate case in which each player may have a fixed number of activity levels. Different set and one-point solution concepts for these games are presented. The properties of these solution concepts and their interrelations on several classes of crisp, fuzzy, and multi-choice games are studied. Applications of the investigated models to many economic situations are indicated as well. The second edition is highly enlarged and contains new results and additional sections in the different chapters as well as one new chapter.

  8. Stochastic models: theory and simulation.

    Energy Technology Data Exchange (ETDEWEB)

    Field, Richard V., Jr.

    2008-03-01

    Many problems in applied science and engineering involve physical phenomena that behave randomly in time and/or space. Examples are diverse and include turbulent flow over an aircraft wing, Earth climatology, material microstructure, and the financial markets. Mathematical models for these random phenomena are referred to as stochastic processes and/or random fields, and Monte Carlo simulation is the only general-purpose tool for solving problems of this type. The use of Monte Carlo simulation requires methods and algorithms to generate samples of the appropriate stochastic model; these samples then become inputs and/or boundary conditions to established deterministic simulation codes. While numerous algorithms and tools currently exist to generate samples of simple random variables and vectors, no cohesive simulation tool yet exists for generating samples of stochastic processes and/or random fields. There are two objectives of this report. First, we provide some theoretical background on stochastic processes and random fields that can be used to model phenomena that are random in space and/or time. Second, we provide simple algorithms that can be used to generate independent samples of general stochastic models. The theory and simulation of random variables and vectors is also reviewed for completeness.

  9. Revisions of the Fish Invasiveness Screening Kit (FISK) for its application in warmer climatic zones, with particular reference to peninsular Florida.

    Science.gov (United States)

    Lawson, Larry L; Hill, Jeffrey E; Vilizzi, Lorenzo; Hardin, Scott; Copp, Gordon H

    2013-08-01

    The initial version (v1) of the Fish Invasiveness Scoring Kit (FISK) was adapted from the Weed Risk Assessment of Pheloung, Williams, and Halloy to assess the potential invasiveness of nonnative freshwater fishes in the United Kingdom. Published applications of FISK v1 have been primarily in temperate-zone countries (Belgium, Belarus, and Japan), so the specificity of this screening tool to that climatic zone was not noted until attempts were made to apply it in peninsular Florida. To remedy this shortcoming, the questions and guidance notes of FISK v1 were reviewed and revised to improve clarity and extend its applicability to broader climatic regions, resulting in changes to 36 of the 49 questions. In addition, upgrades were made to the software architecture of FISK to improve overall computational speed as well as graphical user interface flexibility and friendliness. We demonstrate the process of screening a fish species using FISK v2 in a realistic management scenario by assessing the Barcoo grunter Scortum barcoo (Terapontidae), a species whose management concerns are related to its potential use for aquaponics in Florida. The FISK v2 screening of Barcoo grunter placed the species into the lower range of medium risk (score = 5), suggesting it is a permissible species for use in Florida under current nonnative species regulations. Screening of the Barcoo grunter illustrates the usefulness of FISK v2 as a proactive tool serving to inform risk management decisions, but the low level of confidence associated with the assessment highlighted a dearth of critical information on this species.

  10. Quiver gauge theories and integrable lattice models

    CERN Document Server

    Yagi, Junya

    2015-01-01

    We discuss connections between certain classes of supersymmetric quiver gauge theories and integrable lattice models from the point of view of topological quantum field theories (TQFTs). The relevant classes include 4d $\\mathcal{N} = 1$ theories known as brane box and brane tilling models, 3d $\\mathcal{N} = 2$ and 2d $\\mathcal{N} = (2,2)$ theories obtained from them by compactification, and 2d $\\mathcal{N} = (0,2)$ theories closely related to these theories. We argue that their supersymmetric indices carry structures of TQFTs equipped with line operators, and as a consequence, are equal to the partition functions of lattice models. The integrability of these models follows from the existence of extra dimension in the TQFTs, which emerges after the theories are embedded in M-theory. The Yang-Baxter equation expresses the invariance of supersymmetric indices under Seiberg duality and its lower-dimensional analogs.

  11. Quiver gauge theories and integrable lattice models

    Energy Technology Data Exchange (ETDEWEB)

    Yagi, Junya [International School for Advanced Studies (SISSA),via Bonomea 265, 34136 Trieste (Italy); INFN - Sezione di Trieste,via Valerio 2, 34149 Trieste (Italy)

    2015-10-09

    We discuss connections between certain classes of supersymmetric quiver gauge theories and integrable lattice models from the point of view of topological quantum field theories (TQFTs). The relevant classes include 4d N=1 theories known as brane box and brane tilling models, 3d N=2 and 2d N=(2,2) theories obtained from them by compactification, and 2d N=(0,2) theories closely related to these theories. We argue that their supersymmetric indices carry structures of TQFTs equipped with line operators, and as a consequence, are equal to the partition functions of lattice models. The integrability of these models follows from the existence of extra dimension in the TQFTs, which emerges after the theories are embedded in M-theory. The Yang-Baxter equation expresses the invariance of supersymmetric indices under Seiberg duality and its lower-dimensional analogs.

  12. Enterprise Modelling supported by Manufacturing Systems Theory

    OpenAIRE

    MYKLEBUST, Odd

    2002-01-01

    There exist today a large number of enterprise models or enterprise modelling approaches. In a study of standards and project developed models there are two approaches: CIMOSA “The Open Systems Architecture for CIM” and GERAM, “Generalised Enterprise Reference Architecture”, which show a system orientation that can be further followed as interesting research topics for a system theory oriented approach for enterprise models. In the selection of system theories, manufacturing system theory...

  13. On Dimer Models and Closed String Theories

    OpenAIRE

    Sarkar, Tapobrata

    2007-01-01

    We study some aspects of the recently discovered connection between dimer models and D-brane gauge theories. We argue that dimer models are also naturally related to closed string theories on non compact orbifolds of $\\BC^2$ and $\\BC^3$, via their twisted sector R charges, and show that perfect matchings in dimer models correspond to twisted sector states in the closed string theory. We also use this formalism to study the combinatorics of some unstable orbifolds of $\\BC^2$.

  14. New Pathways between Group Theory and Model Theory

    CERN Document Server

    Fuchs, László; Goldsmith, Brendan; Strüngmann, Lutz

    2017-01-01

    This volume focuses on group theory and model theory with a particular emphasis on the interplay of the two areas. The survey papers provide an overview of the developments across group, module, and model theory while the research papers present the most recent study in those same areas. With introductory sections that make the topics easily accessible to students, the papers in this volume will appeal to beginning graduate students and experienced researchers alike. As a whole, this book offers a cross-section view of the areas in group, module, and model theory, covering topics such as DP-minimal groups, Abelian groups, countable 1-transitive trees, and module approximations. The papers in this book are the proceedings of the conference “New Pathways between Group Theory and Model Theory,” which took place February 1-4, 2016, in Mülheim an der Ruhr, Germany, in honor of the editors’ colleague Rüdiger Göbel. This publication is dedicated to Professor Göbel, who passed away in 2014. He was one of th...

  15. Applications of model theory to functional analysis

    CERN Document Server

    Iovino, Jose

    2014-01-01

    During the last two decades, methods that originated within mathematical logic have exhibited powerful applications to Banach space theory, particularly set theory and model theory. This volume constitutes the first self-contained introduction to techniques of model theory in Banach space theory. The area of research has grown rapidly since this monograph's first appearance, but much of this material is still not readily available elsewhere. For instance, this volume offers a unified presentation of Krivine's theorem and the Krivine-Maurey theorem on stable Banach spaces, with emphasis on the

  16. Domain Theory, Its Models and Concepts

    DEFF Research Database (Denmark)

    Andreasen, Mogens Myrup; Howard, Thomas J.; Bruun, Hans Peter Lomholt

    2014-01-01

    Domain Theory is a systems approach for the analysis and synthesis of products. Its basic idea is to view a product as systems of activities, organs and parts and to define structure, elements, behaviour and function in these domains. The theory is a basis for a long line of research contributions...... and industrial applications especially for the DFX areas (not reported here) and for product modelling. The theory therefore contains a rich ontology of interrelated concepts. The Domain Theory is not aiming to create normative methods but the creation of a collection of concepts related to design phenomena......, which can support design work and to form elements of designers’ mindsets and thereby their practice. The theory is a model-based theory, which means it is composed of concepts and models, which explains certain design phenomena. Many similar theories are described in the literature with differences...

  17. Quantum field theory competitive models

    CERN Document Server

    Tolksdorf, Jürgen; Zeidler, Eberhard

    2009-01-01

    For more than 70 years, quantum field theory (QFT) can be seen as a driving force in the development of theoretical physics. Equally fascinating is the fruitful impact which QFT had in rather remote areas of mathematics. The present book features some of the different approaches, different physically viewpoints and techniques used to make the notion of quantum field theory more precise. For example, the present book contains a discussion including general considerations, stochastic methods, deformation theory and the holographic AdS/CFT correspondence. It also contains a discussion of more recent developments like the use of category theory and topos theoretic methods to describe QFT. The present volume emerged from the 3rd 'Blaubeuren Workshop: Recent Developments in Quantum Field Theory', held in July 2007 at the Max Planck Institute of Mathematics in the Sciences in Leipzig/Germany. All of the contributions are committed to the idea of this workshop series: 'To bring together outstanding experts working in...

  18. A COURT DIVIDED: HARLAN FISKE STONE, JUDICIAL REVIEW, AND ADMINISTRATIVE REGULATION OF THE ECONOMY, 1941-1946

    Directory of Open Access Journals (Sweden)

    Harvey Graham Hudspeth

    2000-01-01

    Full Text Available This essay examines the Supreme Court of Harlan Fiske Stone and its record in the area of government regulation of the economy. As most scholars know, the pre-1937 Court was often dominated by an infamous “Four Horseman” team of economic conservatives who rejected any and all efforts at government regulation. Ironically, by 1943, the Court was often dominated by an equally infamous team of economic radicals who favored government regulation at seemingly all costs — Even at the expense of judicial review.

  19. Theories, Models and Methodology in Writing Research

    NARCIS (Netherlands)

    Rijlaarsdam, Gert; Bergh, van den Huub; Couzijn, Michel

    1996-01-01

    Theories, Models and Methodology in Writing Research describes the current state of the art in research on written text production. The chapters in the first part offer contributions to the creation of new theories and models for writing processes. The second part examines specific elements of the w

  20. The Friction Theory for Viscosity Modeling

    DEFF Research Database (Denmark)

    Cisneros, Sergio; Zeberg-Mikkelsen, Claus Kjær; Stenby, Erling Halfdan

    2001-01-01

    In this work the one-parameter friction theory (f-theory) general models have been extended to the viscosity prediction and modeling of characterized oils. It is demonstrated that these simple models, which take advantage of the repulsive and attractive pressure terms of cubic equations of state...... such as the SRK, PR and PRSV, can provide accurate viscosity prediction and modeling of characterized oils. In the case of light reservoir oils, whose properties are close to those of normal alkanes, the one-parameter f-theory general models can predict the viscosity of these fluids with good accuracy. Yet......, in the case when experimental information is available a more accurate modeling can be obtained by means of a simple tuning procedure. A tuned f-theory general model can deliver highly accurate viscosity modeling above the saturation pressure and good prediction of the liquid-phase viscosity at pressures...

  1. Application of arrangement theory to unfolding models

    CERN Document Server

    Kamiya, Hidehiko; Tokushige, Norihide

    2010-01-01

    Arrangement theory plays an essential role in the study of the unfolding model used in many fields. This paper describes how arrangement theory can be usefully employed in solving the problems of counting (i) the number of admissible rankings in an unfolding model and (ii) the number of ranking patterns generated by unfolding models. The paper is mostly expository but also contains some new results such as simple upper and lower bounds for the number of ranking patterns in the unidimensional case.

  2. Scientific Theories, Models and the Semantic Approach

    Directory of Open Access Journals (Sweden)

    Décio Krause

    2007-12-01

    Full Text Available According to the semantic view, a theory is characterized by a class of models. In this paper, we examine critically some of the assumptions that underlie this approach. First, we recall that models are models of something. Thus we cannot leave completely aside the axiomatization of the theories under consideration, nor can we ignore the metamathematics used to elaborate these models, for changes in the metamathematics often impose restrictions on the resulting models. Second, based on a parallel between van Fraassen’s modal interpretation of quantum mechanics and Skolem’s relativism regarding set-theoretic concepts, we introduce a distinction between relative and absolute concepts in the context of the models of a scientific theory. And we discuss the significance of that distinction. Finally, by focusing on contemporary particle physics, we raise the question: since there is no general accepted unification of the parts of the standard model (namely, QED and QCD, we have no theory, in the usual sense of the term. This poses a difficulty: if there is no theory, how can we speak of its models? What are the latter models of? We conclude by noting that it is unclear that the semantic view can be applied to contemporary physical theories.

  3. Constraint theory multidimensional mathematical model management

    CERN Document Server

    Friedman, George J

    2017-01-01

    Packed with new material and research, this second edition of George Friedman’s bestselling Constraint Theory remains an invaluable reference for all engineers, mathematicians, and managers concerned with modeling. As in the first edition, this text analyzes the way Constraint Theory employs bipartite graphs and presents the process of locating the “kernel of constraint” trillions of times faster than brute-force approaches, determining model consistency and computational allowability. Unique in its abundance of topological pictures of the material, this book balances left- and right-brain perceptions to provide a thorough explanation of multidimensional mathematical models. Much of the extended material in this new edition also comes from Phan Phan’s PhD dissertation in 2011, titled “Expanding Constraint Theory to Determine Well-Posedness of Large Mathematical Models.” Praise for the first edition: "Dr. George Friedman is indisputably the father of the very powerful methods of constraint theory...

  4. The Nomad Model: Theory, Developments and Applications

    NARCIS (Netherlands)

    Campanella, M.; Hoogendoorn, S.P.; Daamen, W.

    2014-01-01

    This paper presents details of the developments of the Nomad model after being introduced more than 12 years ago. The model is derived from a normative theory of pedestrian behavior making it unique under microscopic models. Nomad has been successfully applied in several cases indicating that it ful

  5. Integrable Models, SUSY Gauge Theories, and String Theory

    CERN Document Server

    Nam, S

    1996-01-01

    We consider the close relation between duality in N=2 SUSY gauge theories and integrable models. Vario us integrable models ranging from Toda lattices, Calogero models, spinning tops, and spin chains are re lated to the quantum moduli space of vacua of N=2 SUSY gauge theories. In particular, SU(3) gauge t heories with two flavors of massless quarks in the fundamental representation can be related to the spec tral curve of the Goryachev-Chaplygin top, which is a Nahm's equation in disguise. This can be generaliz ed to the cases with massive quarks, and N_f = 0,1,2, where a system with seven dimensional phas e space has the relevant hyperelliptic curve appear in the Painlevé test. To understand the stringy o rigin of the integrability of these theories we obtain exact nonperturbative point particle limit of ty pe II string compactified on a Calabi-Yau manifold, which gives the hyperelliptic curve of SU(2) QCD w ith N_f =1 hypermultiplet.

  6. A course on basic model theory

    CERN Document Server

    Sarbadhikari, Haimanti

    2017-01-01

    This self-contained book is an exposition of the fundamental ideas of model theory. It presents the necessary background from logic, set theory and other topics of mathematics. Only some degree of mathematical maturity and willingness to assimilate ideas from diverse areas are required. The book can be used for both teaching and self-study, ideally over two semesters. It is primarily aimed at graduate students in mathematical logic who want to specialise in model theory. However, the first two chapters constitute the first introduction to the subject and can be covered in one-semester course to senior undergraduate students in mathematical logic. The book is also suitable for researchers who wish to use model theory in their work.

  7. Lattice Gauge Theories and Spin Models

    CERN Document Server

    Mathur, Manu

    2016-01-01

    The Wegner $Z_2$ gauge theory-$Z_2$ Ising spin model duality in $(2+1)$ dimensions is revisited and derived through a series of canonical transformations. These $Z_2$ results are directly generalized to SU(N) lattice gauge theory in $(2+1)$ dimensions to obtain a dual SU(N) spin model in terms of the SU(N) magnetic fields and electric scalar potentials. The gauge-spin duality naturally leads to a new gauge invariant disorder operator for SU(N) lattice gauge theory. A variational ground state of the dual SU(2) spin model with only nearest neighbour interactions is constructed to analyze SU(2) lattice gauge theory.

  8. Gauge theories and integrable lattice models

    Science.gov (United States)

    Witten, Edward

    1989-08-01

    Investigations of new knot polynomials discovered in the last few years have shown them to be intimately connected with soluble models of two dimensional lattice statistical mechanics. In this paper, these results, which in time may illuminate the whole question of why integrable lattice models exist, are reconsidered from the point of view of three dimensional gauge theory. Expectation values of Wilson lines in three dimensional Chern-Simons gauge theories can be computed by evaluating the partition functions of certain lattice models on finite graphs obtained by projecting the Wilson lines to the plane. The models in question — previously considered in both the knot theory and statistical mechanics — are IRF models in which the local Boltzmann weights are the matrix elements of braiding matrices in rational conformal field theories. These matrix elements, in turn, can be presented in three dimensional gauge theory in terms of the expectation value of a certain tetrahedral configuration of Wilson lines. This representation makes manifest a surprising symmetry of the braiding matrix elements in conformal field theory.

  9. Application of FISK, an invasiveness screening tool for non-native freshwater fishes, in the Murray-Darling Basin (southeastern Australia).

    Science.gov (United States)

    Vilizzi, Lorenzo; Copp, Gordon H

    2013-08-01

    The Fish Invasiveness Scoring Kit (FISK) is currently one of the most popular pre-screening tools for freshwater fishes. A recent upgrade has ensured its wider climatic relevance to countries with subtropical regions. This enhancement is of particular importance to Australia, which encompasses tropical, arid, and temperate zones, and where the introduction of non-native fish species poses a significant risk to biodiversity. In this study, 55 fish species previously evaluated in a U.K.-based calibration of FISK are reassessed for their potential invasiveness in the Murray-Darling Basin (MDB; southeastern Australia), the continent's largest catchment encompassing arid and temperate climates. Approximately half of the species were classed as "medium risk" and the other half as "high risk," and the ≥19 threshold previously identified from the calibration study was confirmed. The three highest scoring species (common carp Cyprinus carpio carpio, goldfish Carassius auratus, and eastern mosquitofish Gambusia holbrooki) were those already present and invasive in the area, whereas nearly half of the tropical and subtropical species had lower scores compared to U.K. assessments, possibly because of climate change predictions of drier conditions across the MDB. There were some discordances between FISK and two Australian-based assessment protocols, one of which is qualitative and the other represents a simplified version of FISK. Notably, the Australian origins of FISK should provide for an additional reason for further applications of the tool in other RA areas (i.e., drainage basins) of the continent, ultimately encouraging adoption as the country's reference screening tool for management and conservation purposes.

  10. Modeling Techniques: Theory and Practice

    OpenAIRE

    Odd A. Asbjørnsen

    1985-01-01

    A survey is given of some crucial concepts in chemical process modeling. Those are the concepts of physical unit invariance, of reaction invariance and stoichiometry, the chromatographic effect in heterogeneous systems, the conservation and balance principles and the fundamental structures of cause and effect relationships. As an example, it is shown how the concept of reaction invariance may simplify the homogeneous reactor modeling to a large extent by an orthogonal decomposition of the pro...

  11. Modeling Techniques: Theory and Practice

    Directory of Open Access Journals (Sweden)

    Odd A. Asbjørnsen

    1985-07-01

    Full Text Available A survey is given of some crucial concepts in chemical process modeling. Those are the concepts of physical unit invariance, of reaction invariance and stoichiometry, the chromatographic effect in heterogeneous systems, the conservation and balance principles and the fundamental structures of cause and effect relationships. As an example, it is shown how the concept of reaction invariance may simplify the homogeneous reactor modeling to a large extent by an orthogonal decomposition of the process variables. This allows residence time distribution function parameters to be estimated with the reaction in situ, but without any correlation between the estimated residence time distribution parameters and the estimated reaction kinetic parameters. A general word of warning is given to the choice of wrong mathematical structure of models.

  12. Grey-theory based intrusion detection model

    Institute of Scientific and Technical Information of China (English)

    Qin Boping; Zhou Xianwei; Yang Jun; Song Cunyi

    2006-01-01

    To solve the problem that current intrusion detection model needs large-scale data in formulating the model in real-time use, an intrusion detection system model based on grey theory (GTIDS) is presented. Grey theory has merits of fewer requirements on original data scale, less limitation of the distribution pattern and simpler algorithm in modeling.With these merits GTIDS constructs model according to partial time sequence for rapid detect on intrusive act in secure system. In this detection model rate of false drop and false retrieval are effectively reduced through twice modeling and repeated detect on target data. Furthermore, GTIDS framework and specific process of modeling algorithm are presented. The affectivity of GTIDS is proved through emulated experiments comparing snort and next-generation intrusion detection expert system (NIDES) in SRI international.

  13. Graphical Model Theory for Wireless Sensor Networks

    Energy Technology Data Exchange (ETDEWEB)

    Davis, William B.

    2002-12-08

    Information processing in sensor networks, with many small processors, demands a theory of computation that allows the minimization of processing effort, and the distribution of this effort throughout the network. Graphical model theory provides a probabilistic theory of computation that explicitly addresses complexity and decentralization for optimizing network computation. The junction tree algorithm, for decentralized inference on graphical probability models, can be instantiated in a variety of applications useful for wireless sensor networks, including: sensor validation and fusion; data compression and channel coding; expert systems, with decentralized data structures, and efficient local queries; pattern classification, and machine learning. Graphical models for these applications are sketched, and a model of dynamic sensor validation and fusion is presented in more depth, to illustrate the junction tree algorithm.

  14. F-theory and linear sigma models

    CERN Document Server

    Bershadsky, M; Greene, Brian R; Johansen, A; Lazaroiu, C I

    1998-01-01

    We present an explicit method for translating between the linear sigma model and the spectral cover description of SU(r) stable bundles over an elliptically fibered Calabi-Yau manifold. We use this to investigate the 4-dimensional duality between (0,2) heterotic and F-theory compactifications. We indirectly find that much interesting heterotic information must be contained in the `spectral bundle' and in its dual description as a gauge theory on multiple F-theory 7-branes. A by-product of these efforts is a method for analyzing semistability and the splitting type of vector bundles over an elliptic curve given as the sheaf cohomology of a monad.

  15. Spreading Models in Banach Space Theory

    CERN Document Server

    Argyros, S A; Tyros, K

    2010-01-01

    We extend the classical Brunel-Sucheston definition of the spreading model by introducing the $\\mathcal{F}$-sequences $(x_s)_{s\\in\\mathcal{F}}$ in a Banach space and the plegma families in $\\mathcal{F}$ where $\\mathcal{F}$ is a regular thin family. The new concept yields a transfinite increasing hierarchy of classes of 1-subsymmetric sequences. We explore the corresponding theory and we present examples establishing this hierarchy and illustrating the limitation of the theory.

  16. Integrable Lattice Models From Gauge Theory

    CERN Document Server

    Witten, Edward

    2016-01-01

    These notes provide an introduction to recent work by Kevin Costello in which integrable lattice models of classical statistical mechanics in two dimensions are understood in terms of quantum gauge theory in four dimensions. This construction will be compared to the more familiar relationship between quantum knot invariants in three dimensions and Chern-Simons gauge theory. (Based on a Whittaker Colloquium at the University of Edinburgh and a lecture at Strings 2016 in Beijing.)

  17. Security Theorems via Model Theory

    Directory of Open Access Journals (Sweden)

    Joshua Guttman

    2009-11-01

    Full Text Available A model-theoretic approach can establish security theorems for cryptographic protocols. Formulas expressing authentication and non-disclosure properties of protocols have a special form. They are quantified implications for all xs . (phi implies for some ys . psi. Models (interpretations for these formulas are *skeletons*, partially ordered structures consisting of a number of local protocol behaviors. *Realized* skeletons contain enough local sessions to explain all the behavior, when combined with some possible adversary behaviors. We show two results. (1 If phi is the antecedent of a security goal, then there is a skeleton A_phi such that, for every skeleton B, phi is satisfied in B iff there is a homomorphism from A_phi to B. (2 A protocol enforces for all xs . (phi implies for some ys . psi iff every realized homomorphic image of A_phi satisfies psi. Hence, to verify a security goal, one can use the Cryptographic Protocol Shapes Analyzer CPSA (TACAS, 2007 to identify minimal realized skeletons, or "shapes," that are homomorphic images of A_phi. If psi holds in each of these shapes, then the goal holds.

  18. Vacation queueing models theory and applications

    CERN Document Server

    Tian, Naishuo

    2006-01-01

    A classical queueing model consists of three parts - arrival process, service process, and queue discipline. However, a vacation queueing model has an additional part - the vacation process which is governed by a vacation policy - that can be characterized by three aspects: 1) vacation start-up rule; 2) vacation termination rule, and 3) vacation duration distribution. Hence, vacation queueing models are an extension of classical queueing theory. Vacation Queueing Models: Theory and Applications discusses systematically and in detail the many variations of vacation policy. By allowing servers to take vacations makes the queueing models more realistic and flexible in studying real-world waiting line systems. Integrated in the book's discussion are a variety of typical vacation model applications that include call centers with multi-task employees, customized manufacturing, telecommunication networks, maintenance activities, etc. Finally, contents are presented in a "theorem and proof" format and it is invaluabl...

  19. Some Remarks on the Model Theory of Epistemic Plausibility Models

    CERN Document Server

    Demey, Lorenz

    2010-01-01

    Classical logics of knowledge and belief are usually interpreted on Kripke models, for which a mathematically well-developed model theory is available. However, such models are inadequate to capture dynamic phenomena. Therefore, epistemic plausibility models have been introduced. Because these are much richer structures than Kripke models, they do not straightforwardly inherit the model-theoretical results of modal logic. Therefore, while epistemic plausibility structures are well-suited for modeling purposes, an extensive investigation of their model theory has been lacking so far. The aim of the present paper is to fill exactly this gap, by initiating a systematic exploration of the model theory of epistemic plausibility models. Like in 'ordinary' modal logic, the focus will be on the notion of bisimulation. We define various notions of bisimulations (parametrized by a language L) and show that L-bisimilarity implies L-equivalence. We prove a Hennesy-Milner type result, and also two undefinability results. ...

  20. Supersymmetric Microscopic Theory of the Standard Model

    CERN Document Server

    Ter-Kazarian, G T

    2000-01-01

    We promote the microscopic theory of standard model (MSM, hep-ph/0007077) into supersymmetric framework in order to solve its technical aspects of vacuum zero point energy and hierarchy problems, and attempt, further, to develop its realistic viable minimal SUSY extension. Among other things that - the MSM provides a natural unification of geometry and the field theory, has clarified the physical conditions in which the geometry and particles come into being, in microscopic sense enables an insight to key problems of particle phenomenology and answers to some of its nagging questions - a present approach also leads to quite a new realization of the SUSY yielding a physically realistic particle spectrum. It stems from the special subquark algebra, from which the nilpotent supercharge operators are derived. The resulting theory makes plausible following testable implications for the current experiments at LEP2, at the Tevatron and at LHC drastically different from those of the conventional MSSM models: 1. All t...

  1. Engaging Theories and Models to Inform Practice

    Science.gov (United States)

    Kraus, Amanda

    2012-01-01

    Helping students prepare for the complex transition to life after graduation is an important responsibility shared by those in student affairs and others in higher education. This chapter explores theories and models that can inform student affairs practitioners and faculty in preparing students for life after college. The focus is on roles,…

  2. Recursive renormalization group theory based subgrid modeling

    Science.gov (United States)

    Zhou, YE

    1991-01-01

    Advancing the knowledge and understanding of turbulence theory is addressed. Specific problems to be addressed will include studies of subgrid models to understand the effects of unresolved small scale dynamics on the large scale motion which, if successful, might substantially reduce the number of degrees of freedom that need to be computed in turbulence simulation.

  3. Aligning Grammatical Theories and Language Processing Models

    Science.gov (United States)

    Lewis, Shevaun; Phillips, Colin

    2015-01-01

    We address two important questions about the relationship between theoretical linguistics and psycholinguistics. First, do grammatical theories and language processing models describe separate cognitive systems, or are they accounts of different aspects of the same system? We argue that most evidence is consistent with the one-system view. Second,…

  4. Lattice gauge theories and spin models

    Science.gov (United States)

    Mathur, Manu; Sreeraj, T. P.

    2016-10-01

    The Wegner Z2 gauge theory-Z2 Ising spin model duality in (2 +1 ) dimensions is revisited and derived through a series of canonical transformations. The Kramers-Wannier duality is similarly obtained. The Wegner Z2 gauge-spin duality is directly generalized to SU(N) lattice gauge theory in (2 +1 ) dimensions to obtain the SU(N) spin model in terms of the SU(N) magnetic fields and their conjugate SU(N) electric scalar potentials. The exact and complete solutions of the Z2, U(1), SU(N) Gauss law constraints in terms of the corresponding spin or dual potential operators are given. The gauge-spin duality naturally leads to a new gauge invariant magnetic disorder operator for SU(N) lattice gauge theory which produces a magnetic vortex on the plaquette. A variational ground state of the SU(2) spin model with nearest neighbor interactions is constructed to analyze SU(2) gauge theory.

  5. F-theory and linear sigma models

    Energy Technology Data Exchange (ETDEWEB)

    Bershadsky, M.; Johansen, A. [Harvard Univ., Cambridge, MA (United States). Lyman Lab. of Physics; Chiang, T.M. [Newman Laboratory of Nuclear Studies, Cornell University, Ithaca, NY 14850 (United States); Greene, B.R.; Lazaroiu, C.I. [Departments of Physics and Mathematics, Columbia University, New York, NY 10027 (United States)

    1998-09-07

    We present an explicit method for translating between the linear sigma model and the spectral cover description of SU(r) stable bundles over an elliptically fibered Calabi-Yau manifold. We use this to investigate the four-dimensional duality between (0,2) heterotic and F-theory compactifications. We indirectly find that much interesting heterotic information must be contained in the `spectral bundle` and in its dual description as a gauge theory on multiple F-theory 7-branes. A by-product of these efforts is a method for analyzing semistability and the splitting type of vector bundles over an elliptic curve given as the sheaf cohomology of a monad. (orig.) 24 refs.

  6. Microscopic Theory of the Standard Model

    CERN Document Server

    Ter-Kazarian, G T

    2000-01-01

    The operator manifold formalism (part I) enables the unification of the geometry and the field theory, and yields the quantization of geometry. This is the mathematical framework for our physical outlook that the geometry and fields, with the internal symmetries and all interactions, as well the four major principles of relativity (special and general), quantum, gauge and colour confinement, are derivative, and come into being simultaneously in the stable system of the underlying ``primordial structures''. In part II we attempt to develop, further, the microscopic approach to the Standard Model of particle physics, which enables an insight to the key problems of particle phenomenology. We suggest the microscopic theory of the unified electroweak interactions. The Higgs bosons have arisen on an analogy of the Cooper pairs in superconductivity. Besides of microscopic interpretation of all physical parameters the resulting theory also makes plausible following testable implications for the current experiments: 1...

  7. Crack propagation modeling using Peridynamic theory

    Science.gov (United States)

    Hafezi, M. H.; Alebrahim, R.; Kundu, T.

    2016-04-01

    Crack propagation and branching are modeled using nonlocal peridynamic theory. One major advantage of this nonlocal theory based analysis tool is the unifying approach towards material behavior modeling - irrespective of whether the crack is formed in the material or not. No separate damage law is needed for crack initiation and propagation. This theory overcomes the weaknesses of existing continuum mechanics based numerical tools (e.g. FEM, XFEM etc.) for identifying fracture modes and does not require any simplifying assumptions. Cracks grow autonomously and not necessarily along a prescribed path. However, in some special situations such as in case of ductile fracture, the damage evolution and failure depend on parameters characterizing the local stress state instead of peridynamic damage modeling technique developed for brittle fracture. For brittle fracture modeling the bond is simply broken when the failure criterion is satisfied. This simulation helps us to design more reliable modeling tool for crack propagation and branching in both brittle and ductile materials. Peridynamic analysis has been found to be very demanding computationally, particularly for real-world structures (e.g. vehicles, aircrafts, etc.). It also requires a very expensive visualization process. The goal of this paper is to bring awareness to researchers the impact of this cutting-edge simulation tool for a better understanding of the cracked material response. A computer code has been developed to implement the peridynamic theory based modeling tool for two-dimensional analysis. A good agreement between our predictions and previously published results is observed. Some interesting new results that have not been reported earlier by others are also obtained and presented in this paper. The final objective of this investigation is to increase the mechanics knowledge of self-similar and self-affine cracks.

  8. Topos models for physics and topos theory

    Science.gov (United States)

    Wolters, Sander

    2014-08-01

    What is the role of topos theory in the topos models for quantum theory as used by Isham, Butterfield, Döring, Heunen, Landsman, Spitters, and others? In other words, what is the interplay between physical motivation for the models and the mathematical framework used in these models? Concretely, we show that the presheaf topos model of Butterfield, Isham, and Döring resembles classical physics when viewed from the internal language of the presheaf topos, similar to the copresheaf topos model of Heunen, Landsman, and Spitters. Both the presheaf and copresheaf models provide a "quantum logic" in the form of a complete Heyting algebra. Although these algebras are natural from a topos theoretic stance, we seek a physical interpretation for the logical operations. Finally, we investigate dynamics. In particular, we describe how an automorphism on the operator algebra induces a homeomorphism (or isomorphism of locales) on the associated state spaces of the topos models, and how elementary propositions and truth values transform under the action of this homeomorphism. Also with dynamics the focus is on the internal perspective of the topos.

  9. A Membrane Model from Implicit Elasticity Theory

    Science.gov (United States)

    Freed, A. D.; Liao, J.; Einstein, D. R.

    2014-01-01

    A Fungean solid is derived for membranous materials as a body defined by isotropic response functions whose mathematical structure is that of a Hookean solid where the elastic constants are replaced by functions of state derived from an implicit, thermodynamic, internal-energy function. The theory utilizes Biot’s (1939) definitions for stress and strain that, in 1-dimension, are the stress/strain measures adopted by Fung (1967) when he postulated what is now known as Fung’s law. Our Fungean membrane model is parameterized against a biaxial data set acquired from a porcine pleural membrane subjected to three, sequential, proportional, planar extensions. These data support an isotropic/deviatoric split in the stress and strain-rate hypothesized by our theory. These data also demonstrate that the material response is highly non-linear but, otherwise, mechanically isotropic. These data are described reasonably well by our otherwise simple, four-parameter, material model. PMID:24282079

  10. Theory, Modeling and Simulation Annual Report 2000

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, David A.; Garrett, Bruce C.; Straatsma, Tp; Jones, Donald R.; Studham, Ronald S.; Harrison, Robert J.; Nichols, Jeffrey A.

    2001-11-01

    This annual report describes the 2000 research accomplishments for the Theory, Modeling, and Simulation (TM&S) directorate, one of the six research organizations in the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL) at Pacific Northwest National Laboratory (PNNL). EMSL is a U.S. Department of Energy (DOE) national scientific user facility and is the centerpiece of the DOE commitment to providing world-class experimental, theoretical, and computational capabilities for solving the nation's environmental problems.

  11. Theory, Modeling and Simulation Annual Report 2000

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, David A; Garrett, Bruce C; Straatsma, TP; Jones, Donald R; Studham, Scott; Harrison, Robert J; Nichols, Jeffrey A

    2001-11-01

    This annual report describes the 2000 research accomplishments for the Theory, Modeling, and Simulation (TM and S) directorate, one of the six research organizations in the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL) at Pacific Northwest National Laboratory (PNNL). EMSL is a U.S. Department of Energy (DOE) national scientific user facility and is the centerpiece of the DOE commitment to providing world-class experimental, theoretical, and computational capabilities for solving the nation's environmental problems.

  12. Sparse modeling theory, algorithms, and applications

    CERN Document Server

    Rish, Irina

    2014-01-01

    ""A comprehensive, clear, and well-articulated book on sparse modeling. This book will stand as a prime reference to the research community for many years to come.""-Ricardo Vilalta, Department of Computer Science, University of Houston""This book provides a modern introduction to sparse methods for machine learning and signal processing, with a comprehensive treatment of both theory and algorithms. Sparse Modeling is an ideal book for a first-year graduate course.""-Francis Bach, INRIA - École Normale Supřieure, Paris

  13. Theory, modeling and simulation: Annual report 1993

    Energy Technology Data Exchange (ETDEWEB)

    Dunning, T.H. Jr.; Garrett, B.C.

    1994-07-01

    Developing the knowledge base needed to address the environmental restoration issues of the US Department of Energy requires a fundamental understanding of molecules and their interactions in insolation and in liquids, on surfaces, and at interfaces. To meet these needs, the PNL has established the Environmental and Molecular Sciences Laboratory (EMSL) and will soon begin construction of a new, collaborative research facility devoted to advancing the understanding of environmental molecular science. Research in the Theory, Modeling, and Simulation program (TMS), which is one of seven research directorates in the EMSL, will play a critical role in understanding molecular processes important in restoring DOE`s research, development and production sites, including understanding the migration and reactions of contaminants in soils and groundwater, the development of separation process for isolation of pollutants, the development of improved materials for waste storage, understanding the enzymatic reactions involved in the biodegradation of contaminants, and understanding the interaction of hazardous chemicals with living organisms. The research objectives of the TMS program are to apply available techniques to study fundamental molecular processes involved in natural and contaminated systems; to extend current techniques to treat molecular systems of future importance and to develop techniques for addressing problems that are computationally intractable at present; to apply molecular modeling techniques to simulate molecular processes occurring in the multispecies, multiphase systems characteristic of natural and polluted environments; and to extend current molecular modeling techniques to treat complex molecular systems and to improve the reliability and accuracy of such simulations. The program contains three research activities: Molecular Theory/Modeling, Solid State Theory, and Biomolecular Modeling/Simulation. Extended abstracts are presented for 89 studies.

  14. An Optimization Model Based on Game Theory

    Directory of Open Access Journals (Sweden)

    Yang Shi

    2014-04-01

    Full Text Available Game Theory has a wide range of applications in department of economics, but in the field of computer science, especially in the optimization algorithm is seldom used. In this paper, we integrate thinking of game theory into optimization algorithm, and then propose a new optimization model which can be widely used in optimization processing. This optimization model is divided into two types, which are called “the complete consistency” and “the partial consistency”. In these two types, the partial consistency is added disturbance strategy on the basis of the complete consistency. When model’s consistency is satisfied, the Nash equilibrium of the optimization model is global optimal and when the model’s consistency is not met, the presence of perturbation strategy can improve the application of the algorithm. The basic experiments suggest that this optimization model has broad applicability and better performance, and gives a new idea for some intractable problems in the field of artificial intelligence

  15. Bridging Economic Theory Models and the Cointegrated Vector Autoregressive Model

    DEFF Research Database (Denmark)

    Møller, Niels Framroze

    2008-01-01

    Examples of simple economic theory models are analyzed as restrictions on the Cointegrated VAR (CVAR). This establishes a correspondence between basic economic concepts and the econometric concepts of the CVAR: The economic relations correspond to cointegrating vectors and exogeneity in the econo......Examples of simple economic theory models are analyzed as restrictions on the Cointegrated VAR (CVAR). This establishes a correspondence between basic economic concepts and the econometric concepts of the CVAR: The economic relations correspond to cointegrating vectors and exogeneity...... parameters of the CVAR are shown to be interpretable in terms of expectations formation, market clearing, nominal rigidities, etc. The general-partial equilibrium distinction is also discussed....

  16. Bridging Economic Theory Models and the Cointegrated Vector Autoregressive Model

    DEFF Research Database (Denmark)

    Møller, Niels Framroze

    2008-01-01

    Examples of simple economic theory models are analyzed as restrictions on the Cointegrated VAR (CVAR). This establishes a correspondence between basic economic concepts and the econometric concepts of the CVAR: The economic relations correspond to cointegrating vectors and exogeneity in the econo......Examples of simple economic theory models are analyzed as restrictions on the Cointegrated VAR (CVAR). This establishes a correspondence between basic economic concepts and the econometric concepts of the CVAR: The economic relations correspond to cointegrating vectors and exogeneity...... are related to expectations formation, market clearing, nominal rigidities, etc. Finally, the general-partial equilibrium distinction is analyzed....

  17. Bridging Economic Theory Models and the Cointegrated Vector Autoregressive Model

    DEFF Research Database (Denmark)

    Møller, Niels Framroze

    2008-01-01

    Examples of simple economic theory models are analyzed as restrictions on the Cointegrated VAR (CVAR). This establishes a correspondence between basic economic concepts and the econometric concepts of the CVAR: The economic relations correspond to cointegrating vectors and exogeneity in the econo......Examples of simple economic theory models are analyzed as restrictions on the Cointegrated VAR (CVAR). This establishes a correspondence between basic economic concepts and the econometric concepts of the CVAR: The economic relations correspond to cointegrating vectors and exogeneity...... are related to expectations formation, market clearing, nominal rigidities, etc. Finally, the general-partial equilibrium distinction is analyzed....

  18. Bridging Economic Theory Models and the Cointegrated Vector Autoregressive Model

    DEFF Research Database (Denmark)

    Møller, Niels Framroze

    2008-01-01

    Examples of simple economic theory models are analyzed as restrictions on the Cointegrated VAR (CVAR). This establishes a correspondence between basic economic concepts and the econometric concepts of the CVAR: The economic relations correspond to cointegrating vectors and exogeneity in the econo......Examples of simple economic theory models are analyzed as restrictions on the Cointegrated VAR (CVAR). This establishes a correspondence between basic economic concepts and the econometric concepts of the CVAR: The economic relations correspond to cointegrating vectors and exogeneity...... parameters of the CVAR are shown to be interpretable in terms of expectations formation, market clearing, nominal rigidities, etc. The general-partial equilibrium distinction is also discussed....

  19. Queuing theory models for computer networks

    Science.gov (United States)

    Galant, David C.

    1989-01-01

    A set of simple queuing theory models which can model the average response of a network of computers to a given traffic load has been implemented using a spreadsheet. The impact of variations in traffic patterns and intensities, channel capacities, and message protocols can be assessed using them because of the lack of fine detail in the network traffic rates, traffic patterns, and the hardware used to implement the networks. A sample use of the models applied to a realistic problem is included in appendix A. Appendix B provides a glossary of terms used in this paper. This Ames Research Center computer communication network is an evolving network of local area networks (LANs) connected via gateways and high-speed backbone communication channels. Intelligent planning of expansion and improvement requires understanding the behavior of the individual LANs as well as the collection of networks as a whole.

  20. Economic contract theory tests models of mutualism.

    Science.gov (United States)

    Weyl, E Glen; Frederickson, Megan E; Yu, Douglas W; Pierce, Naomi E

    2010-09-01

    Although mutualisms are common in all ecological communities and have played key roles in the diversification of life, our current understanding of the evolution of cooperation applies mostly to social behavior within a species. A central question is whether mutualisms persist because hosts have evolved costly punishment of cheaters. Here, we use the economic theory of employment contracts to formulate and distinguish between two mechanisms that have been proposed to prevent cheating in host-symbiont mutualisms, partner fidelity feedback (PFF) and host sanctions (HS). Under PFF, positive feedback between host fitness and symbiont fitness is sufficient to prevent cheating; in contrast, HS posits the necessity of costly punishment to maintain mutualism. A coevolutionary model of mutualism finds that HS are unlikely to evolve de novo, and published data on legume-rhizobia and yucca-moth mutualisms are consistent with PFF and not with HS. Thus, in systems considered to be textbook cases of HS, we find poor support for the theory that hosts have evolved to punish cheating symbionts; instead, we show that even horizontally transmitted mutualisms can be stabilized via PFF. PFF theory may place previously underappreciated constraints on the evolution of mutualism and explain why punishment is far from ubiquitous in nature.

  1. A matrix model from string field theory

    Directory of Open Access Journals (Sweden)

    Syoji Zeze

    2016-09-01

    Full Text Available We demonstrate that a Hermitian matrix model can be derived from level truncated open string field theory with Chan-Paton factors. The Hermitian matrix is coupled with a scalar and U(N vectors which are responsible for the D-brane at the tachyon vacuum. Effective potential for the scalar is evaluated both for finite and large N. Increase of potential height is observed in both cases. The large $N$ matrix integral is identified with a system of N ZZ branes and a ghost FZZT brane.

  2. Polarimetric clutter modeling: Theory and application

    Science.gov (United States)

    Kong, J. A.; Lin, F. C.; Borgeaud, M.; Yueh, H. A.; Swartz, A. A.; Lim, H. H.; Shim, R. T.; Novak, L. M.

    1988-01-01

    The two-layer anisotropic random medium model is used to investigate fully polarimetric scattering properties of earth terrain media. The polarization covariance matrices for the untilted and tilted uniaxial random medium are evaluated using the strong fluctuation theory and distorted Born approximation. In order to account for the azimuthal randomness in the growth direction of leaves in tree and grass fields, an averaging scheme over the azimuthal direction is also applied. It is found that characteristics of terrain clutter can be identified through the analysis of each element of the covariance matrix. Theoretical results are illustrated by the comparison with experimental data provided by MIT Lincoln Laboratory for tree and grass fields.

  3. A matrix model from string field theory

    Science.gov (United States)

    Zeze, Syoji

    2016-09-01

    We demonstrate that a Hermitian matrix model can be derived from level truncated open string field theory with Chan-Paton factors. The Hermitian matrix is coupled with a scalar and U(N) vectors which are responsible for the D-brane at the tachyon vacuum. Effective potential for the scalar is evaluated both for finite and large N. Increase of potential height is observed in both cases. The large N matrix integral is identified with a system of N ZZ branes and a ghost FZZT brane.

  4. Quantum Model Theory (QMod): Modeling Contextual Emergent Entangled Interfering Entities

    CERN Document Server

    Aerts, Diederik

    2012-01-01

    In this paper we present 'Quantum Model Theory' (QMod), a theory we developed to model entities that entail the typical quantum effects of 'contextuality, 'superposition', 'interference', 'entanglement' and 'emergence'. This aim of QMod is to put forward a theoretical framework that has the technical power of standard quantum mechanics, namely it makes explicitly use of the standard complex Hilbert space and its quantum mechanical calculus, but is also more general than standard quantum mechanics, in the sense that it only uses this quantum calculus locally, i.e. for each context corresponding to a measurement. In this sense, QMod is a generalization of quantum mechanics, similar to how the general relativity manifold mathematical formalism is a generalization of special relativity and classical physics. We prove by means of a representation theorem that QMod can be used for any entity entailing the typical quantum effects mentioned above. Some examples of application of QMod in concept theory and macroscopic...

  5. Moral Distress Model Reconstructed Using Grounded Theory.

    Science.gov (United States)

    Ko, Hsun-Kuei; Chin, Chi-Chun; Hsu, Min-Tao

    2016-12-29

    The problems of nurse burnout and manpower shortage relate to moral distress. Thus, having a good understanding of moral distress is critical to developing strategies that effectively improve the clinical ethical climate and improve nursing retention in Taiwan. The aim of this study was to reconstruct the model of moral distress using the grounded theory. Twenty-five staff nurses at work units who attend to the needs of adult, pediatric, acute, and critical disease or end-of-life-care patients were recruited as participants using theoretical sampling from three teaching hospitals in Taiwan. Data were collected using intensive, 2- to 3-hour interviews with each participant. Audio recordings of the interviews were made and then converted into transcripts. The data were analyzed using the grounded theory. In the clinical setting, the perspective that nurses take toward clinical moral events reflects their moral values, which trigger moral cognition, provocation, and appraisal. The moral barriers that form when moral events that occur in clinical settings contradict personal moral values may later develop into moral distress. In handling moral barriers in the clinical environment, nurses make moral judgments and determine what is morally correct. Influenced by moral efficacy, the consequence may either be a moral action or an expression of personal emotion. Wasting National Health Insurance resources and Chinese culture are key sources of moral distress for nurses in Taiwan. The role of self-confidence in promoting moral efficacy and the role of heterodox skills in promoting moral actions represent findings that are unique to this study. The moral distress model was used in this study to facilitate the development of future nursing theories. On the basis of our findings, we suggested that nursing students be encouraged to use case studies to establish proper moral values, improve moral cognition and judgment capabilities, and promote moral actions to better handle the

  6. Application of Chaos Theory to Psychological Models

    Science.gov (United States)

    Blackerby, Rae Fortunato

    This dissertation shows that an alternative theoretical approach from physics--chaos theory--offers a viable basis for improved understanding of human beings and their behavior. Chaos theory provides achievable frameworks for potential identification, assessment, and adjustment of human behavior patterns. Most current psychological models fail to address the metaphysical conditions inherent in the human system, thus bringing deep errors to psychological practice and empirical research. Freudian, Jungian and behavioristic perspectives are inadequate psychological models because they assume, either implicitly or explicitly, that the human psychological system is a closed, linear system. On the other hand, Adlerian models that require open systems are likely to be empirically tenable. Logically, models will hold only if the model's assumptions hold. The innovative application of chaotic dynamics to psychological behavior is a promising theoretical development because the application asserts that human systems are open, nonlinear and self-organizing. Chaotic dynamics use nonlinear mathematical relationships among factors that influence human systems. This dissertation explores these mathematical relationships in the context of a sample model of moral behavior using simulated data. Mathematical equations with nonlinear feedback loops describe chaotic systems. Feedback loops govern the equations' value in subsequent calculation iterations. For example, changes in moral behavior are affected by an individual's own self-centeredness, family and community influences, and previous moral behavior choices that feed back to influence future choices. When applying these factors to the chaos equations, the model behaves like other chaotic systems. For example, changes in moral behavior fluctuate in regular patterns, as determined by the values of the individual, family and community factors. In some cases, these fluctuations converge to one value; in other cases, they diverge in

  7. An Inflationary Model in String Theory

    CERN Document Server

    Iizuka, N; Iizuka, Norihiro; Trivedi, Sandip P.

    2004-01-01

    We construct a model of inflation in string theory after carefully taking into account moduli stabilization. The setting is a warped compactification of Type IIB string theory in the presence of D3 and anti-D3-branes. The inflaton is the position of a D3-brane in the internal space. By suitably adjusting fluxes and the location of symmetrically placed anti-D3-branes, we show that at a point of enhanced symmetry, the inflaton potential V can have a broad maximum, satisfying the condition V''/V << 1 in Planck units. On starting close to the top of this potential the slow-roll conditions can be met. Observational constraints impose significant restrictions. As a first pass we show that these can be satisfied and determine the important scales in the compactification to within an order of magnitude. One robust feature is that the scale of inflation is low, H = O(10^{10}) GeV. Removing the observational constraints makes it much easier to construct a slow-roll inflationary model. Generalizations and conseque...

  8. Modified perturbation theory for the Yukawa model

    CERN Document Server

    Poluektov, Yu M

    2016-01-01

    A new formulation of perturbation theory for a description of the Dirac and scalar fields (the Yukawa model) is suggested. As the main approximation the self-consistent field model is chosen, which allows in a certain degree to account for the effects caused by the interaction of fields. Such choice of the main approximation leads to a normally ordered form of the interaction Hamiltonian. Generation of the fermion mass due to the interaction with exchange of the scalar boson is investigated. It is demonstrated that, for zero bare mass, the fermion can acquire mass only if the coupling constant exceeds the critical value determined by the boson mass. In this connection, the problem of the neutrino mass is discussed.

  9. PARFUME Theory and Model basis Report

    Energy Technology Data Exchange (ETDEWEB)

    Darrell L. Knudson; Gregory K Miller; G.K. Miller; D.A. Petti; J.T. Maki; D.L. Knudson

    2009-09-01

    The success of gas reactors depends upon the safety and quality of the coated particle fuel. The fuel performance modeling code PARFUME simulates the mechanical, thermal and physico-chemical behavior of fuel particles during irradiation. This report documents the theory and material properties behind vari¬ous capabilities of the code, which include: 1) various options for calculating CO production and fission product gas release, 2) an analytical solution for stresses in the coating layers that accounts for irradiation-induced creep and swelling of the pyrocarbon layers, 3) a thermal model that calculates a time-dependent temperature profile through a pebble bed sphere or a prismatic block core, as well as through the layers of each analyzed particle, 4) simulation of multi-dimensional particle behavior associated with cracking in the IPyC layer, partial debonding of the IPyC from the SiC, particle asphericity, and kernel migration (or amoeba effect), 5) two independent methods for determining particle failure probabilities, 6) a model for calculating release-to-birth (R/B) ratios of gaseous fission products that accounts for particle failures and uranium contamination in the fuel matrix, and 7) the evaluation of an accident condition, where a particle experiences a sudden change in temperature following a period of normal irradiation. The accident condi¬tion entails diffusion of fission products through the particle coating layers and through the fuel matrix to the coolant boundary. This document represents the initial version of the PARFUME Theory and Model Basis Report. More detailed descriptions will be provided in future revisions.

  10. Stochastic linear programming models, theory, and computation

    CERN Document Server

    Kall, Peter

    2011-01-01

    This new edition of Stochastic Linear Programming: Models, Theory and Computation has been brought completely up to date, either dealing with or at least referring to new material on models and methods, including DEA with stochastic outputs modeled via constraints on special risk functions (generalizing chance constraints, ICC’s and CVaR constraints), material on Sharpe-ratio, and Asset Liability Management models involving CVaR in a multi-stage setup. To facilitate use as a text, exercises are included throughout the book, and web access is provided to a student version of the authors’ SLP-IOR software. Additionally, the authors have updated the Guide to Available Software, and they have included newer algorithms and modeling systems for SLP. The book is thus suitable as a text for advanced courses in stochastic optimization, and as a reference to the field. From Reviews of the First Edition: "The book presents a comprehensive study of stochastic linear optimization problems and their applications. … T...

  11. Modeling and Optimization : Theory and Applications Conference

    CERN Document Server

    Terlaky, Tamás

    2015-01-01

    This volume contains a selection of contributions that were presented at the Modeling and Optimization: Theory and Applications Conference (MOPTA) held at Lehigh University in Bethlehem, Pennsylvania, USA on August 13-15, 2014. The conference brought together a diverse group of researchers and practitioners, working on both theoretical and practical aspects of continuous or discrete optimization. Topics presented included algorithms for solving convex, network, mixed-integer, nonlinear, and global optimization problems, and addressed the application of deterministic and stochastic optimization techniques in energy, finance, logistics, analytics, healthcare, and other important fields. The contributions contained in this volume represent a sample of these topics and applications and illustrate the broad diversity of ideas discussed at the meeting.

  12. Theory and modelling of nanocarbon phase stability.

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, A. S.

    2006-01-01

    The transformation of nanodiamonds into carbon-onions (and vice versa) has been observed experimentally and has been modeled computationally at various levels of sophistication. Also, several analytical theories have been derived to describe the size, temperature and pressure dependence of this phase transition. However, in most cases a pure carbon-onion or nanodiamond is not the final product. More often than not an intermediary is formed, known as a bucky-diamond, with a diamond-like core encased in an onion-like shell. This has prompted a number of studies investigating the relative stability of nanodiamonds, bucky-diamonds, carbon-onions and fullerenes, in various size regimes. Presented here is a review outlining results of numerous theoretical studies examining the phase diagrams and phase stability of carbon nanoparticles, to clarify the complicated relationship between fullerenic and diamond structures at the nanoscale.

  13. Galaxy alignments: Theory, modelling and simulations

    CERN Document Server

    Kiessling, Alina; Joachimi, Benjamin; Kirk, Donnacha; Kitching, Thomas D; Leonard, Adrienne; Mandelbaum, Rachel; Schäfer, Björn Malte; Sifón, Cristóbal; Brown, Michael L; Rassat, Anais

    2015-01-01

    The shapes of galaxies are not randomly oriented on the sky. During the galaxy formation and evolution process, environment has a strong influence, as tidal gravitational fields in large-scale structure tend to align the shapes and angular momenta of nearby galaxies. Additionally, events such as galaxy mergers affect the relative alignments of galaxies throughout their history. These "intrinsic galaxy alignments" are known to exist, but are still poorly understood. This review will offer a pedagogical introduction to the current theories that describe intrinsic galaxy alignments, including the apparent difference in intrinsic alignment between early- and late-type galaxies and the latest efforts to model them analytically. It will then describe the ongoing efforts to simulate intrinsic alignments using both $N$-body and hydrodynamic simulations. Due to the relative youth of this field, there is still much to be done to understand intrinsic galaxy alignments and this review summarises the current state of the ...

  14. Modeling missing data in knowledge space theory.

    Science.gov (United States)

    de Chiusole, Debora; Stefanutti, Luca; Anselmi, Pasquale; Robusto, Egidio

    2015-12-01

    Missing data are a well known issue in statistical inference, because some responses may be missing, even when data are collected carefully. The problem that arises in these cases is how to deal with missing data. In this article, the missingness is analyzed in knowledge space theory, and in particular when the basic local independence model (BLIM) is applied to the data. Two extensions of the BLIM to missing data are proposed: The former, called ignorable missing BLIM (IMBLIM), assumes that missing data are missing completely at random; the latter, called missing BLIM (MissBLIM), introduces specific dependencies of the missing data on the knowledge states, thus assuming that the missing data are missing not at random. The IMBLIM and the MissBLIM modeled the missingness in a satisfactory way, in both a simulation study and an empirical application, depending on the process that generates the missingness: If the missing data-generating process is of type missing completely at random, then either IMBLIM or MissBLIM provide adequate fit to the data. However, if the pattern of missingness is functionally dependent upon unobservable features of the data (e.g., missing answers are more likely to be wrong), then only a correctly specified model of the missingness distribution provides an adequate fit to the data.

  15. A Mathematical Theory of the Gauged Linear Sigma Model

    CERN Document Server

    Fan, Huijun; Ruan, Yongbin

    2015-01-01

    We construct a rigorous mathematical theory of Witten's Gauged Linear Sigma Model (GLSM). Our theory applies to a wide range of examples, including many cases with non-Abelian gauge group. Both the Gromov-Witten theory of a Calabi-Yau complete intersection X and the Landau-Ginzburg dual (FJRW-theory) of X can be expressed as gauged linear sigma models. Furthermore, the Landau-Ginzburg/Calabi-Yau correspondence can be interpreted as a variation of the moment map or a deformation of GIT in the GLSM. This paper focuses primarily on the algebraic theory, while a companion article will treat the analytic theory.

  16. The Properties of Model Selection when Retaining Theory Variables

    DEFF Research Database (Denmark)

    Hendry, David F.; Johansen, Søren

    Economic theories are often fitted directly to data to avoid possible model selection biases. We show that embedding a theory model that specifies the correct set of m relevant exogenous variables, x{t}, within the larger set of m+k candidate variables, (x{t},w{t}), then selection over the second...... set by their statistical significance can be undertaken without affecting the estimator distribution of the theory parameters. This strategy returns the theory-parameter estimates when the theory is correct, yet protects against the theory being under-specified because some w{t} are relevant....

  17. Gravothermal Star Clusters - Theory and Computer Modelling

    Science.gov (United States)

    Spurzem, Rainer

    2010-11-01

    In the George Darwin lecture, delivered to the British Royal Astronomical Society in 1960 by Viktor A. Ambartsumian he wrote on the evolution of stellar systems that it can be described by the "dynamic evolution of a gravitating gas" complemented by "a statistical description of the changes in the physical states of stars". This talk will show how this physical concept has inspired theoretical modeling of star clusters in the following decades up to the present day. The application of principles of thermodynamics shows, as Ambartsumian argued in his 1960 lecture, that there is no stable state of equilibrium of a gravitating star cluster. The trend to local thermodynamic equilibrium is always disturbed by escaping stars (Ambartsumian), as well as by gravothermal and gravogyro instabilities, as it was detected later. Here the state-of-the-art of modeling the evolution of dense stellar systems based on principles of thermodynamics and statistical mechanics (Fokker-Planck approximation) will be reviewed. Recent progress including rotation and internal correlations (primordial binaries) is presented. The models have also very successfully been used to study dense star clusters around massive black holes in galactic nuclei and even (in a few cases) relativistic supermassive dense objects in centres of galaxies (here again briefly touching one of the many research fields of V.A. Ambartsumian). For the modern present time of high-speed supercomputing, where we are tackling direct N-body simulations of star clusters, we will show that such direct modeling supports and proves the concept of the statistical models based on the Fokker-Planck theory, and that both theoretical concepts and direct computer simulations are necessary to support each other and make scientific progress in the study of star cluster evolution.

  18. A Realizability Model for Impredicative Hoare Type Theory

    DEFF Research Database (Denmark)

    Petersen, Rasmus Lerchedal; Birkedal, Lars; Nanevski, Alexandar

    2008-01-01

    We present a denotational model of impredicative Hoare Type Theory, a very expressive dependent type theory in which one can specify and reason about mutable abstract data types. The model ensures soundness of the extension of Hoare Type Theory with impredicative polymorphism; makes the connections...... to separation logic clear, and provides a basis for investigation of further sound extensions of the theory, in particular equations between computations and types....

  19. Venture Theory: A Model of Decision Weights.

    Science.gov (United States)

    1988-01-01

    restrictions are important in that nonadditive decision weights can be used to "explain" many anomalies of standard choice theory . Implications. There are...1974). On utility functions. Theory and Decision, 5, 205-242. Chew, S. H., & MacCrimmon, K. R. Alpha-nu choice theory : A generalization of expected

  20. Model of Polyakov duality: String field theory Hamiltonians from Yang-Mills theories

    Science.gov (United States)

    Periwal, Vipul

    2000-08-01

    Polyakov has conjectured that Yang-Mills theory should be equivalent to a noncritical string theory. I point out, based on the work of Marchesini, Ishibashi, Kawai and collaborators, and Jevicki and Rodrigues, that the loop operator of the Yang-Mills theory is the temporal gauge string field theory Hamiltonian of a noncritical string theory. The consistency condition of the string interpretation is the zig-zag symmetry emphasized by Polyakov. I explicitly show how this works for the one-plaquette model, providing a consistent direct string interpretation of the unitary matrix model for the first time.

  1. Risk assessment of non-native fishes in the Balkans Region using FISK, the invasiveness screening tool for non-native freshwater fishes

    Directory of Open Access Journals (Sweden)

    P. SIMONOVIC

    2013-06-01

    Full Text Available A high level of freshwater fish endemism in the Balkans Region emphasizes the need for non-native species risk assessments to inform management and control measures, with pre-screening tools, such as the Fish Invasiveness Screening Kit (FISK providing a useful first step. Applied to 43 non-native and translocated freshwater fishes in four Balkan countries, FISK reliably discriminated between invasive and non-invasive species, with a calibration threshold value of 9.5 distinguishing between species of medium and high risk sensu lato of becoming invasive. Twelve of the 43 species were assessed by scientists from two or more Balkan countries, and the remaining 31 species by a single assessor. Using the 9.5 threshold, three species were classed as low risk, 10 as medium risk, and 30 as high risk, with the latter category comprised of 26 moderately high risk, three high risk, and one very high risk species. Confidence levels in the assessments were relatively constant for all species, indicating concordance amongst assessors.

  2. Density functional theory and multiscale materials modeling

    Indian Academy of Sciences (India)

    Swapan K Ghosh

    2003-01-01

    One of the vital ingredients in the theoretical tools useful in materials modeling at all the length scales of interest is the concept of density. In the microscopic length scale, it is the electron density that has played a major role in providing a deeper understanding of chemical binding in atoms, molecules and solids. In the intermediate mesoscopic length scale, an appropriate picture of the equilibrium and dynamical processes has been obtained through the single particle number density of the constituent atoms or molecules. A wide class of problems involving nanomaterials, interfacial science and soft condensed matter has been addressed using the density based theoretical formalism as well as atomistic simulation in this regime. In the macroscopic length scale, however, matter is usually treated as a continuous medium and a description using local mass density, energy density and other related density functions has been found to be quite appropriate. A unique single unified theoretical framework that emerges through the density concept at these diverse length scales and is applicable to both quantum and classical systems is the so called density functional theory (DFT) which essentially provides a vehicle to project the many-particle picture to a single particle one. Thus, the central equation for quantum DFT is a one-particle Schrödinger-like Kohn–Sham equation, while the same for classical DFT consists of Boltzmann type distributions, both corresponding to a system of noninteracting particles in the field of a density-dependent effective potential. Selected illustrative applications of quantum DFT to microscopic modeling of intermolecular interaction and that of classical DFT to a mesoscopic modeling of soft condensed matter systems are presented.

  3. Models of Particle Physics from Type IIB String Theory and F-theory: A Review

    CERN Document Server

    Maharana, Anshuman

    2012-01-01

    We review particle physics model building in type IIB string theory and F-theory. This is a region in the landscape where in principle many of the key ingredients required for a realistic model of particle physics can be combined successfully. We begin by reviewing moduli stabilisation within this framework and its implications for supersymmetry breaking. We then review model building tools and developments in the weakly coupled type IIB limit, for both local D3-branes at singularities and global models of intersecting D7-branes. Much of recent model building work has been in the strongly coupled regime of F-theory due to the presence of exceptional symmetries which allow for the construction of phenomenologically appealing Grand Unified Theories. We review both local and global F-theory model building starting from the fundamental concepts and tools regarding how the gauge group, matter sector and operators arise, and ranging to detailed phenomenological properties explored in the literature.

  4. String-like dual models for scalar theories

    Science.gov (United States)

    Baadsgaard, Christian; Bjerrum-Bohr, N. E. J.; Bourjaily, Jacob; Damgaard, Poul H.

    2016-12-01

    We show that all tree-level amplitudes in φ p scalar field theory can be represented as the α ' → 0 limit of an SL(2, ℝ)-invariant, string-theory-like dual model integral. These dual models are constructed according to constraints that admit families of solutions. We derive these dual models, and give closed formulae for all tree-level amplitudes of any φ p scalar field theory.

  5. String-Like Dual Models for Scalar Theories

    CERN Document Server

    Baadsgaard, Christian; Bourjaily, Jacob L; Damgaard, Poul H

    2016-01-01

    We show that all tree-level amplitudes in $\\varphi^p$ scalar field theory can be represented as the $\\alpha'\\to0$ limit of an $SL(2,R)$-invariant, string-theory-like dual model integral. These dual models are constructed according to constraints that admit families of solutions. We derive these dual models, and give closed formulae for all tree-level amplitudes of any $\\varphi^p$ scalar field theory.

  6. Catastrophe Theory: A Unified Model for Educational Change.

    Science.gov (United States)

    Cryer, Patricia; Elton, Lewis

    1990-01-01

    Catastrophe Theory and Herzberg's theory of motivation at work was used to create a model of change that unifies and extends Lewin's two separate stage and force field models. This new model is used to analyze the behavior of academics as they adapt to the changing university environment. (Author/MLW)

  7. Catastrophe Theory: A Unified Model for Educational Change.

    Science.gov (United States)

    Cryer, Patricia; Elton, Lewis

    1990-01-01

    Catastrophe Theory and Herzberg's theory of motivation at work was used to create a model of change that unifies and extends Lewin's two separate stage and force field models. This new model is used to analyze the behavior of academics as they adapt to the changing university environment. (Author/MLW)

  8. Chaos Theory as a Model for Managing Issues and Crises.

    Science.gov (United States)

    Murphy, Priscilla

    1996-01-01

    Uses chaos theory to model public relations situations in which the salient feature is volatility of public perceptions. Discusses the premises of chaos theory and applies them to issues management, the evolution of interest groups, crises, and rumors. Concludes that chaos theory is useful as an analogy to structure image problems and to raise…

  9. The Theory of Finite Models without Equal Sign

    Institute of Scientific and Technical Information of China (English)

    Li Bo LUO

    2006-01-01

    In this paper, it is the first time ever to suggest that we study the model theory of all finite structures and to put the equal sign in the same situtation as the other relations. Using formulas of infinite lengths we obtain new theorems for the preservation of model extensions, submodels, model homomorphisms and inverse homomorphisms. These kinds of theorems were discussed in Chang and Keisler's Model Theory, systematically for general models, but Gurevich obtained some different theorems in this direction for finite models. In our paper the old theorems manage to survive in the finite model theory. There are some differences between into homomorphisms and onto homomorphisms in preservation theorems too. We also study reduced models and minimum models. The characterization sentence of a model is given, which derives a general result for any theory T to be equivalent to a set of existential-universal sentences. Some results about completeness and model completeness are also given.

  10. Making sense of implementation theories, models and frameworks

    National Research Council Canada - National Science Library

    Nilsen, Per

    2015-01-01

    .... The aim of this article is to propose a taxonomy that distinguishes between different categories of theories, models and frameworks in implementation science, to facilitate appropriate selection...

  11. Theory and modeling of active brazing.

    Energy Technology Data Exchange (ETDEWEB)

    van Swol, Frank B.; Miller, James Edward; Lechman, Jeremy B.; Givler, Richard C.

    2013-09-01

    Active brazes have been used for many years to produce bonds between metal and ceramic objects. By including a relatively small of a reactive additive to the braze one seeks to improve the wetting and spreading behavior of the braze. The additive modifies the substrate, either by a chemical surface reaction or possibly by alloying. By its nature, the joining process with active brazes is a complex nonequilibrium non-steady state process that couples chemical reaction, reactant and product diffusion to the rheology and wetting behavior of the braze. Most of the these subprocesses are taking place in the interfacial region, most are difficult to access by experiment. To improve the control over the brazing process, one requires a better understanding of the melting of the active braze, rate of the chemical reaction, reactant and product diffusion rates, nonequilibrium composition-dependent surface tension as well as the viscosity. This report identifies ways in which modeling and theory can assist in improving our understanding.

  12. Information Theory: a Multifaceted Model of Information

    Directory of Open Access Journals (Sweden)

    Mark Burgin

    2003-06-01

    Full Text Available A contradictory and paradoxical situation that currently exists in information studies can be improved by the introduction of a new information approach, which is called the general theory of information. The main achievement of the general theory of information is explication of a relevant and adequate definition of information. This theory is built as a system of two classes of principles (ontological and sociological and their consequences. Axiological principles, which explain how to measure and evaluate information and information processes, are presented in the second section of this paper. These principles systematize and unify different approaches, existing as well as possible, to construction and utilization of information measures. Examples of such measures are given by Shannon’s quantity of information, algorithmic quantity of information or volume of information. It is demonstrated that all other known directions of information theory may be treated inside general theory of information as its particular cases.

  13. Hypergame Theory: A Model for Conflict, Misperception, and Deception

    Directory of Open Access Journals (Sweden)

    Nicholas S. Kovach

    2015-01-01

    Full Text Available When dealing with conflicts, game theory and decision theory can be used to model the interactions of the decision-makers. To date, game theory and decision theory have received considerable modeling focus, while hypergame theory has not. A metagame, known as a hypergame, occurs when one player does not know or fully understand all the strategies of a game. Hypergame theory extends the advantages of game theory by allowing a player to outmaneuver an opponent and obtaining a more preferred outcome with a higher utility. The ability to outmaneuver an opponent occurs in the hypergame because the different views (perception or deception of opponents are captured in the model, through the incorporation of information unknown to other players (misperception or intentional deception. The hypergame model more accurately provides solutions for complex theoretic modeling of conflicts than those modeled by game theory and excels where perception or information differences exist between players. This paper explores the current research in hypergame theory and presents a broad overview of the historical literature on hypergame theory.

  14. QUANTUM THEORY FOR THE BINOMIAL MODEL IN FINANCE THEORY

    Institute of Scientific and Technical Information of China (English)

    CHEN Zeqian

    2004-01-01

    In this paper, a quantum model for the binomial market in finance is proposed. We show that its risk-neutral world exhibits an intriguing structure as a disk in the unit ball of R3, whose radius is a function of the risk-free interest rate with two thresholds which prevent arbitrage opportunities from this quantum market. Furthermore, from the quantum mechanical point of view we re-deduce the Cox-Ross-Rubinstein binomial option pricing formula by considering Maxwell-Boltzmann statistics of the system of N distinguishable particles.

  15. MULTI-FLEXIBLE SYSTEM DYNAMIC MODELING THEORY AND APPLICATION

    Institute of Scientific and Technical Information of China (English)

    仲昕; 周兵; 杨汝清

    2001-01-01

    The flexible body modeling theory was demonstrated. An example of modeling a kind of automobile's front suspension as a multi-flexible system was shown. Finally, it shows that the simulation results of multi-flexible dynamic model more approach the road test data than those of multi-rigid dynamic model do. Thus, it is fully testified that using multi-flexible body theory to model is necessary and effective.

  16. The Standard Model is Natural as Magnetic Gauge Theory

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2011-01-01

    matter. The absence of scalars in the electric theory indicates that the associated magnetic theory is free from quadratic divergences. Our novel solution to the Standard Model hierarchy problem leads also to a new insight on the mystery of the observed number of fundamental fermion generations......We suggest that the Standard Model can be viewed as the magnetic dual of a gauge theory featuring only fermionic matter content. We show this by first introducing a Pati-Salam like extension of the Standard Model and then relating it to a possible dual electric theory featuring only fermionic...

  17. Summary of papers presented in the Theory and Modelling session

    OpenAIRE

    Lin-Liu Y.R.; Westerhof E.

    2012-01-01

    A total of 14 contributions were presented in the Theory and Modelling sessions at EC-17. One Theory and Modelling paper was included in the ITER ECRH and ECE sessions each. Three papers were in the area of nonlinear physics discussing parametric processes accompanying ECRH. Eight papers were based on the quasi-linear theory of wave heating and current drive. Three of these addressed the application of ECCD for NTM stabilization. Two papers considered scattering of EC waves by edge density fl...

  18. The logical foundations of scientific theories languages, structures, and models

    CERN Document Server

    Krause, Decio

    2016-01-01

    This book addresses the logical aspects of the foundations of scientific theories. Even though the relevance of formal methods in the study of scientific theories is now widely recognized and regaining prominence, the issues covered here are still not generally discussed in philosophy of science. The authors focus mainly on the role played by the underlying formal apparatuses employed in the construction of the models of scientific theories, relating the discussion with the so-called semantic approach to scientific theories. The book describes the role played by this metamathematical framework in three main aspects: considerations of formal languages employed to axiomatize scientific theories, the role of the axiomatic method itself, and the way set-theoretical structures, which play the role of the models of theories, are developed. The authors also discuss the differences and philosophical relevance of the two basic ways of aximoatizing a scientific theory, namely Patrick Suppes’ set theoretical predicate...

  19. Solid modeling and applications rapid prototyping, CAD and CAE theory

    CERN Document Server

    Um, Dugan

    2016-01-01

    The lessons in this fundamental text equip students with the theory of Computer Assisted Design (CAD), Computer Assisted Engineering (CAE), the essentials of Rapid Prototyping, as well as practical skills needed to apply this understanding in real world design and manufacturing settings. The book includes three main areas: CAD, CAE, and Rapid Prototyping, each enriched with numerous examples and exercises. In the CAD section, Professor Um outlines the basic concept of geometric modeling, Hermite and Bezier Spline curves theory, and 3-dimensional surface theories as well as rendering theory. The CAE section explores mesh generation theory, matrix notion for FEM, the stiffness method, and truss Equations. And in Rapid Prototyping, the author illustrates stereo lithographic theory and introduces popular modern RP technologies. Solid Modeling and Applications: Rapid Prototyping, CAD and CAE Theory is ideal for university students in various engineering disciplines as well as design engineers involved in product...

  20. Matrix models, topological strings, and supersymmetric gauge theories

    Science.gov (United States)

    Dijkgraaf, Robbert; Vafa, Cumrun

    2002-11-01

    We show that B-model topological strings on local Calabi-Yau threefolds are large- N duals of matrix models, which in the planar limit naturally give rise to special geometry. These matrix models directly compute F-terms in an associated N=1 supersymmetric gauge theory, obtained by deforming N=2 theories by a superpotential term that can be directly identified with the potential of the matrix model. Moreover by tuning some of the parameters of the geometry in a double scaling limit we recover ( p, q) conformal minimal models coupled to 2d gravity, thereby relating non-critical string theories to type II superstrings on Calabi-Yau backgrounds.

  1. Introduction to gauge theories and the Standard Model

    CERN Document Server

    de Wit, Bernard

    1995-01-01

    The conceptual basis of gauge theories is introduced to enable the construction of generic models.Spontaneous symmetry breaking is dicussed and its relevance for the renormalization of theories with massive vector field is explained. Subsequently a d standard model. When time permits we will address more practical questions that arise in the evaluation of quantum corrections.

  2. A Quantitative Causal Model Theory of Conditional Reasoning

    Science.gov (United States)

    Fernbach, Philip M.; Erb, Christopher D.

    2013-01-01

    The authors propose and test a causal model theory of reasoning about conditional arguments with causal content. According to the theory, the acceptability of modus ponens (MP) and affirming the consequent (AC) reflect the conditional likelihood of causes and effects based on a probabilistic causal model of the scenario being judged. Acceptability…

  3. The Properties of Model Selection when Retaining Theory Variables

    DEFF Research Database (Denmark)

    Hendry, David F.; Johansen, Søren

    Economic theories are often fitted directly to data to avoid possible model selection biases. We show that embedding a theory model that specifies the correct set of m relevant exogenous variables, x{t}, within the larger set of m+k candidate variables, (x{t},w{t}), then selection over the second...

  4. Application of multidimensional item response theory models to longitudinal data

    NARCIS (Netherlands)

    Marvelde, te Janneke M.; Glas, Cees A.W.; Van Landeghem, Georges; Van Damme, Jan

    2006-01-01

    The application of multidimensional item response theory (IRT) models to longitudinal educational surveys where students are repeatedly measured is discussed and exemplified. A marginal maximum likelihood (MML) method to estimate the parameters of a multidimensional generalized partial credit model

  5. Item response theory modeling with nonignorable missing data

    NARCIS (Netherlands)

    Pimentel, Jonald L.

    2005-01-01

    This thesis discusses methods to detect nonignorable missing data and methods to adjust for the bias caused by nonignorable missing data, both by introducing a model for the missing data indicator using item response theory (IRT) models.

  6. Theory of stellar convection - II. First stellar models

    Science.gov (United States)

    Pasetto, S.; Chiosi, C.; Chiosi, E.; Cropper, M.; Weiss, A.

    2016-07-01

    We present here the first stellar models on the Hertzsprung-Russell diagram, in which convection is treated according to the new scale-free convection theory (SFC theory) by Pasetto et al. The aim is to compare the results of the new theory with those from the classical, calibrated mixing-length (ML) theory to examine differences and similarities. We integrate the equations describing the structure of the atmosphere from the stellar surface down to a few per cent of the stellar mass using both ML theory and SFC theory. The key temperature over pressure gradients, the energy fluxes, and the extension of the convective zones are compared in both theories. The analysis is first made for the Sun and then extended to other stars of different mass and evolutionary stage. The results are adequate: the SFC theory yields convective zones, temperature gradients ∇ and ∇e, and energy fluxes that are very similar to those derived from the `calibrated' MT theory for main-sequence stars. We conclude that the old scale dependent ML theory can now be replaced with a self-consistent scale-free theory able to predict correct results, as it is more physically grounded than the ML theory. Fundamentally, the SFC theory offers a deeper insight of the underlying physics than numerical simulations.

  7. Large field inflation models from higher-dimensional gauge theories

    Science.gov (United States)

    Furuuchi, Kazuyuki; Koyama, Yoji

    2015-02-01

    Motivated by the recent detection of B-mode polarization of CMB by BICEP2 which is possibly of primordial origin, we study large field inflation models which can be obtained from higher-dimensional gauge theories. The constraints from CMB observations on the gauge theory parameters are given, and their naturalness are discussed. Among the models analyzed, Dante's Inferno model turns out to be the most preferred model in this framework.

  8. Large field inflation models from higher-dimensional gauge theories

    Energy Technology Data Exchange (ETDEWEB)

    Furuuchi, Kazuyuki [Manipal Centre for Natural Sciences, Manipal University, Manipal, Karnataka 576104 (India); Koyama, Yoji [Department of Physics, National Tsing-Hua University, Hsinchu 30013, Taiwan R.O.C. (China)

    2015-02-23

    Motivated by the recent detection of B-mode polarization of CMB by BICEP2 which is possibly of primordial origin, we study large field inflation models which can be obtained from higher-dimensional gauge theories. The constraints from CMB observations on the gauge theory parameters are given, and their naturalness are discussed. Among the models analyzed, Dante’s Inferno model turns out to be the most preferred model in this framework.

  9. Theories, models and urban realities. From New York to Kathmandu

    Directory of Open Access Journals (Sweden)

    Román Rodríguez González

    2004-12-01

    Full Text Available At the beginning of the 21st century, there are various social theories that speak of global changes in the history of human civilization. Urban models have been through obvious changes throughout the last century according to the important transformation that are pro-posed by previous general theories. Nevertheless global diversity contradicts the generaliza-tion of these theories and models. From our own simple observations and reflections we arrive at conclusions that distance themselves from the prevailing theory of our civilized world. New York, Delhi, Salvador de Bahia, Bruges, Paris, Cartagena de Indias or Kath-mandu still have more internal differences than similarities.

  10. Theories, models and urban realities. From New York to Kathmandu

    Directory of Open Access Journals (Sweden)

    José Somoza Medina

    2004-01-01

    Full Text Available At the beginning of the 21st century, there are various social theories that speak of globalchanges in the history of human civilization. Urban models have been through obviouschanges throughout the last century according to the important transformation that are proposedby previous general theories. Nevertheless global diversity contradicts the generalizationof these theories and models. From our own simple observations and reflections wearrive at conclusions that distance themselves from the prevailing theory of our civilizedworld. New York, Delhi, Salvador de Bahia, Bruges, Paris, Cartagena de Indias or Kathmandustill have more internal differences than similarities.

  11. Toric Methods in F-Theory Model Building

    Directory of Open Access Journals (Sweden)

    Johanna Knapp

    2011-01-01

    Full Text Available We discuss recent constructions of global F-theory GUT models and explain how to make use of toric geometry to do calculations within this framework. After introducing the basic properties of global F-theory GUTs, we give a self-contained review of toric geometry and introduce all the tools that are necessary to construct and analyze global F-theory models. We will explain how to systematically obtain a large class of compact Calabi-Yau fourfolds which can support F-theory GUTs by using the software package PALP.

  12. General autocatalytic theory and simple model of financial markets

    Science.gov (United States)

    Thuy Anh, Chu; Lan, Nguyen Tri; Viet, Nguyen Ai

    2015-06-01

    The concept of autocatalytic theory has become a powerful tool in understanding evolutionary processes in complex systems. A generalization of autocatalytic theory was assumed by considering that the initial element now is being some distribution instead of a constant value as in traditional theory. This initial condition leads to that the final element might have some distribution too. A simple physics model for financial markets is proposed, using this general autocatalytic theory. Some general behaviours of evolution process and risk moment of a financial market also are investigated in framework of this simple model.

  13. Værdioptimering af fiskefangsten i dansk blandet fiskeri (VærdiFisk) - forbedret kvalitet og selektion som følge af redskabsudvikling

    DEFF Research Database (Denmark)

    Karlsen, Junita Diana; Krag, Ludvig Ahm; Lund, Henrik S.

    The FishValue-project (VærdiFisk) led to the development of a vertically divided codend with prospects of increasing the income in the Danish mixed fishery in several ways. Separation of fish and Nephrops (Nephrops norvegicus) in an upper and lower codend, respectively, led to a significant...... catch. Design and placement of a grid in the lower codend gave an effective separation of all the four fish species investigated in addition to Nephrops when compared to the first version of the experimental codend. When separated in a different codend than Nephrops, the skin of both roundfish...... as measured by the quality parameters included in this study. There are many factors other than quality that governs the price at the auction, e.g. the amount of fish at the action, the size of the lot where small quantities like the ones in the project typically obtain lower prices, the demand in the market...

  14. Applications of Generalizability Theory and Their Relations to Classical Test Theory and Structural Equation Modeling.

    Science.gov (United States)

    Vispoel, Walter P; Morris, Carrie A; Kilinc, Murat

    2017-01-23

    Although widely recognized as a comprehensive framework for representing score reliability, generalizability theory (G-theory), despite its potential benefits, has been used sparingly in reporting of results for measures of individual differences. In this article, we highlight many valuable ways that G-theory can be used to quantify, evaluate, and improve psychometric properties of scores. Our illustrations encompass assessment of overall reliability, percentages of score variation accounted for by individual sources of measurement error, dependability of cut-scores for decision making, estimation of reliability and dependability for changes made to measurement procedures, disattenuation of validity coefficients for measurement error, and linkages of G-theory with classical test theory and structural equation modeling. We also identify computer packages for performing G-theory analyses, most of which can be obtained free of charge, and describe how they compare with regard to data input requirements, ease of use, complexity of designs supported, and output produced. (PsycINFO Database Record

  15. Dimensional reduction of Markov state models from renormalization group theory

    Science.gov (United States)

    Orioli, S.; Faccioli, P.

    2016-09-01

    Renormalization Group (RG) theory provides the theoretical framework to define rigorous effective theories, i.e., systematic low-resolution approximations of arbitrary microscopic models. Markov state models are shown to be rigorous effective theories for Molecular Dynamics (MD). Based on this fact, we use real space RG to vary the resolution of the stochastic model and define an algorithm for clustering microstates into macrostates. The result is a lower dimensional stochastic model which, by construction, provides the optimal coarse-grained Markovian representation of the system's relaxation kinetics. To illustrate and validate our theory, we analyze a number of test systems of increasing complexity, ranging from synthetic toy models to two realistic applications, built form all-atom MD simulations. The computational cost of computing the low-dimensional model remains affordable on a desktop computer even for thousands of microstates.

  16. Dimensional reduction of Markov state models from renormalization group theory.

    Science.gov (United States)

    Orioli, S; Faccioli, P

    2016-09-28

    Renormalization Group (RG) theory provides the theoretical framework to define rigorous effective theories, i.e., systematic low-resolution approximations of arbitrary microscopic models. Markov state models are shown to be rigorous effective theories for Molecular Dynamics (MD). Based on this fact, we use real space RG to vary the resolution of the stochastic model and define an algorithm for clustering microstates into macrostates. The result is a lower dimensional stochastic model which, by construction, provides the optimal coarse-grained Markovian representation of the system's relaxation kinetics. To illustrate and validate our theory, we analyze a number of test systems of increasing complexity, ranging from synthetic toy models to two realistic applications, built form all-atom MD simulations. The computational cost of computing the low-dimensional model remains affordable on a desktop computer even for thousands of microstates.

  17. Turbulent Boundary Layers - Experiments, Theory and Modelling

    Science.gov (United States)

    1980-01-01

    DEVELOPMENT (ORGANISATION DU TRAITE DE L’ATLANTIQUE NORD ) AGARD Conference Proceedings No.271 TURBULENT BOUNDARY LAYERS - EXPERIMENTS, THEORY AND...photographs of Figures 21 and 22. In this case, the photographs are taken with a single flash strobe and thus yield the instantaneous positions of the

  18. Reconstructing constructivism: Causal models, Bayesian learning mechanisms and the theory theory

    OpenAIRE

    Gopnik, Alison; Wellman, Henry M.

    2012-01-01

    We propose a new version of the “theory theory” grounded in the computational framework of probabilistic causal models and Bayesian learning. Probabilistic models allow a constructivist but rigorous and detailed approach to cognitive development. They also explain the learning of both more specific causal hypotheses and more abstract framework theories. We outline the new theoretical ideas, explain the computational framework in an intuitive and non-technical way, and review an extensive but ...

  19. The mathematical theory of reduced MHD models for fusion plasmas

    OpenAIRE

    Guillard, Hervé

    2015-01-01

    The derivation of reduced MHD models for fusion plasma is here formulated as a special instance of the general theory of singular limit of hyperbolic system of PDEs with large operator. This formulation allows to use the general results of this theory and to prove rigorously that reduced MHD models are valid approximations of the full MHD equations. In particular, it is proven that the solutions of the full MHD system converge to the solutions of an appropriate reduced model.

  20. Gutzwiller variational theory for the Hubbard model with attractive interaction.

    Science.gov (United States)

    Bünemann, Jörg; Gebhard, Florian; Radnóczi, Katalin; Fazekas, Patrik

    2005-06-29

    We investigate the electronic and superconducting properties of a negative-U Hubbard model. For this purpose we evaluate a recently introduced variational theory based on Gutzwiller-correlated BCS wavefunctions. We find significant differences between our approach and standard BCS theory, especially for the superconducting gap. For small values of |U|, we derive analytical expressions for the order parameter and the superconducting gap which we compare to exact results from perturbation theory.

  1. Nonequilibrium Dynamical Mean-Field Theory for Bosonic Lattice Models

    OpenAIRE

    2015-01-01

    We develop the nonequilibrium extension of bosonic dynamical mean-field theory and a Nambu real-time strong-coupling perturbative impurity solver. In contrast to Gutzwiller mean-field theory and strong-coupling perturbative approaches, nonequilibrium bosonic dynamical mean-field theory captures not only dynamical transitions but also damping and thermalization effects at finite temperature. We apply the formalism to quenches in the Bose-Hubbard model, starting from both the normal and the Bos...

  2. Geometry model construction in infrared image theory simulation of buildings

    Institute of Scientific and Technical Information of China (English)

    谢鸣; 李玉秀; 徐辉; 谈和平

    2004-01-01

    Geometric model construction is the basis of infrared image theory simulation. Taking the construction of the geometric model of one building in Harbin as an example, this paper analyzes the theoretical groundings of simplification and principles of geometric model construction of buildings. It then discusses some particular treatment methods in calculating the radiation transfer coefficient in geometric model construction using the Monte Carlo Method.

  3. Theory and model use in social marketing health interventions.

    Science.gov (United States)

    Luca, Nadina Raluca; Suggs, L Suzanne

    2013-01-01

    The existing literature suggests that theories and models can serve as valuable frameworks for the design and evaluation of health interventions. However, evidence on the use of theories and models in social marketing interventions is sparse. The purpose of this systematic review is to identify to what extent papers about social marketing health interventions report using theory, which theories are most commonly used, and how theory was used. A systematic search was conducted for articles that reported social marketing interventions for the prevention or management of cancer, diabetes, heart disease, HIV, STDs, and tobacco use, and behaviors related to reproductive health, physical activity, nutrition, and smoking cessation. Articles were published in English, after 1990, reported an evaluation, and met the 6 social marketing benchmarks criteria (behavior change, consumer research, segmentation and targeting, exchange, competition and marketing mix). Twenty-four articles, describing 17 interventions, met the inclusion criteria. Of these 17 interventions, 8 reported using theory and 7 stated how it was used. The transtheoretical model/stages of change was used more often than other theories. Findings highlight an ongoing lack of use or underreporting of the use of theory in social marketing campaigns and reinforce the call to action for applying and reporting theory to guide and evaluate interventions.

  4. Modeling Routinization in Games: An Information Theory Approach

    DEFF Research Database (Denmark)

    Wallner, Simon; Pichlmair, Martin; Hecher, Michael

    2015-01-01

    -time, discrete-space Markov chains and information theory to measure the actual error between the dynamically trained models and the player interaction. Preliminary research supports the hypothesis that Markov chains can be effectively used to model routinization in games. A full study design is presented......Routinization is the result of practicing until an action stops being a goal-directed process. This paper formulates a definition of routinization in games based on prior research in the fields of activity theory and practice theory. Routinization is analyzed using the formal model of discrete...

  5. Modeling Routinization in Games: An Information Theory Approach

    DEFF Research Database (Denmark)

    Wallner, Simon; Pichlmair, Martin; Hecher, Michael

    2015-01-01

    Routinization is the result of practicing until an action stops being a goal-directed process. This paper formulates a definition of routinization in games based on prior research in the fields of activity theory and practice theory. Routinization is analyzed using the formal model of discrete......-time, discrete-space Markov chains and information theory to measure the actual error between the dynamically trained models and the player interaction. Preliminary research supports the hypothesis that Markov chains can be effectively used to model routinization in games. A full study design is presented...

  6. Theories and models of globalization ethicizing

    Directory of Open Access Journals (Sweden)

    Dritan Abazović

    2016-05-01

    Full Text Available Globalization as a phenomenon is under the magnifying glass of many philosophical discussions and theoretical deliberations. While most theorists deal with issues that are predominantly of economic or political character, this article has a different logic. The article presents six theories which in their own way explain the need for movement by ethicizing globalization. Globalization is a process that affects all and as such it has become inevitable, but it is up the people to determine its course and make it either functional or uncontrolled. The survival and development of any society is measured primarily by the quality of its moral and ethical foundation. Therefore, it is clear that global society can survive and be functional only if it finds a minimum consensus on ethical norms or, as said in theory, if it establishes its ethical system based on which it would be built and developed.

  7. The danger model: questioning an unconvincing theory.

    Science.gov (United States)

    Józefowski, Szczepan

    2016-02-01

    Janeway's pattern recognition theory holds that the immune system detects infection through a limited number of the so-called pattern recognition receptors (PRRs). These receptors bind specific chemical compounds expressed by entire groups of related pathogens, but not by host cells (pathogen-associated molecular patterns (PAMPs). In contrast, Matzinger's danger hypothesis postulates that products released from stressed or damaged cells have a more important role in the activation of immune system than the recognition of nonself. These products, named by analogy to PAMPs as danger-associated molecular patterns (DAMPs), are proposed to act through the same receptors (PRRs) as PAMPs and, consequently, to stimulate largely similar responses. Herein, I review direct and indirect evidence that contradict the widely accepted danger theory, and suggest that it may be false.

  8. [Models of economic theory of population growth].

    Science.gov (United States)

    Von Zameck, W

    1987-01-01

    "The economic theory of population growth applies the opportunity cost approach to the fertility decision. Variations and differentials in fertility are caused by the available resources and relative prices or by the relative production costs of child services. Pure changes in real income raise the demand for children or the total amount spent on children. If relative prices or production costs and real income are affected together the effect on fertility requires separate consideration." (SUMMARY IN ENG)

  9. Measurement Models for Reasoned Action Theory

    OpenAIRE

    Hennessy, Michael; Bleakley, Amy; FISHBEIN, MARTIN

    2012-01-01

    Quantitative researchers distinguish between causal and effect indicators. What are the analytic problems when both types of measures are present in a quantitative reasoned action analysis? To answer this question, we use data from a longitudinal study to estimate the association between two constructs central to reasoned action theory: behavioral beliefs and attitudes toward the behavior. The belief items are causal indicators that define a latent variable index while the attitude items are ...

  10. Theory, modeling, and simulation annual report, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1993-05-01

    This report briefly discusses research on the following topics: development of electronic structure methods; modeling molecular processes in clusters; modeling molecular processes in solution; modeling molecular processes in separations chemistry; modeling interfacial molecular processes; modeling molecular processes in the atmosphere; methods for periodic calculations on solids; chemistry and physics of minerals; graphical user interfaces for computational chemistry codes; visualization and analysis of molecular simulations; integrated computational chemistry environment; and benchmark computations.

  11. A Model of the Economic Theory of Regulation for Undergraduates.

    Science.gov (United States)

    Wilson, Brooks

    1995-01-01

    Presents a model of the economic theory of regulation and recommends its use in undergraduate economics classes. Describes the use of computer-assisted instruction to teach the theory. Maintains that the approach enables students to gain access to graphs and tables that they produce themselves. (CFR)

  12. A continuum theory for modeling the dynamics of crystalline materials.

    Science.gov (United States)

    Xiong, Liming; Chen, Youping; Lee, James D

    2009-02-01

    This paper introduces a multiscale field theory for modeling and simulation of the dynamics of crystalline materials. The atomistic formulation of a multiscale field theory is briefly introduced. Its applicability is discussed. A few application examples, including phonon dispersion relations of ferroelectric materials BiScO3 and MgO nano dot under compression are presented.

  13. Theory analysis of the Dental Hygiene Human Needs Conceptual Model.

    Science.gov (United States)

    MacDonald, L; Bowen, D M

    2016-11-09

    Theories provide a structural knowing about concept relationships, practice intricacies, and intuitions and thus shape the distinct body of the profession. Capturing ways of knowing and being is essential to any professions' practice, education and research. This process defines the phenomenon of the profession - its existence or experience. Theory evaluation is a systematic criterion-based assessment of a specific theory. This study presents a theory analysis of the Dental Hygiene Human Needs Conceptual Model (DH HNCM). Using the Walker and Avant Theory Analysis, a seven-step process, the DH HNCM, was analysed and evaluated for its meaningfulness and contribution to dental hygiene. The steps include the following: (i) investigate the origins; (ii) examine relationships of the theory's concepts; (iii) assess the logic of the theory's structure; (iv) consider the usefulness to practice; (v) judge the generalizability; (vi) evaluate the parsimony; and (vii) appraise the testability of the theory. Human needs theory in nursing and Maslow's Hierarchy of Need Theory prompted this theory's development. The DH HNCM depicts four concepts based on the paradigm concepts of the profession: client, health/oral health, environment and dental hygiene actions, and includes validated eleven human needs that evolved overtime to eight. It is logical, simplistic, allows scientific predictions and testing, and provides a unique lens for the dental hygiene practitioner. With this model, dental hygienists have entered practice, knowing they enable clients to meet their human needs. For the DH HNCM, theory analysis affirmed that the model is reasonable and insightful and adds to the dental hygiene professions' epistemology and ontology. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Modeling Multivariate Volatility Processes: Theory and Evidence

    Directory of Open Access Journals (Sweden)

    Jelena Z. Minovic

    2009-05-01

    Full Text Available This article presents theoretical and empirical methodology for estimation and modeling of multivariate volatility processes. It surveys the model specifications and the estimation methods. Multivariate GARCH models covered are VEC (initially due to Bollerslev, Engle and Wooldridge, 1988, diagonal VEC (DVEC, BEKK (named after Baba, Engle, Kraft and Kroner, 1995, Constant Conditional Correlation Model (CCC, Bollerslev, 1990, Dynamic Conditional Correlation Model (DCC models of Tse and Tsui, 2002, and Engle, 2002. I illustrate approach by applying it to daily data from the Belgrade stock exchange, I examine two pairs of daily log returns for stocks and index, report the results obtained, and compare them with the restricted version of BEKK, DVEC and CCC representations. The methods for estimation parameters used are maximum log-likehood (in BEKK and DVEC models and twostep approach (in CCC model.

  15. Extended Nambu models: Their relation to gauge theories

    Science.gov (United States)

    Escobar, C. A.; Urrutia, L. F.

    2017-05-01

    Yang-Mills theories supplemented by an additional coordinate constraint, which is solved and substituted in the original Lagrangian, provide examples of the so-called Nambu models, in the case where such constraints arise from spontaneous Lorentz symmetry breaking. Some explicit calculations have shown that, after additional conditions are imposed, Nambu models are capable of reproducing the original gauge theories, thus making Lorentz violation unobservable and allowing the interpretation of the corresponding massless gauge bosons as the Goldstone bosons arising from the spontaneous symmetry breaking. A natural question posed by this approach in the realm of gauge theories is to determine under which conditions the recovery of an arbitrary gauge theory from the corresponding Nambu model, defined by a general constraint over the coordinates, becomes possible. We refer to these theories as extended Nambu models (ENM) and emphasize the fact that the defining coordinate constraint is not treated as a standard gauge fixing term. At this level, the mechanism for generating the constraint is irrelevant and the case of spontaneous Lorentz symmetry breaking is taken only as a motivation, which naturally bring this problem under consideration. Using a nonperturbative Hamiltonian analysis we prove that the ENM yields the original gauge theory after we demand current conservation for all time, together with the imposition of the Gauss laws constraints as initial conditions upon the dynamics of the ENM. The Nambu models yielding electrodynamics, Yang-Mills theories and linearized gravity are particular examples of our general approach.

  16. A Model of PCF in Guarded Type Theory

    DEFF Research Database (Denmark)

    Paviotti, Marco; Møgelberg, Rasmus Ejlers; Birkedal, Lars

    2015-01-01

    of coinductive types. In this paper we investigate how type theory with guarded recursion can be used as a metalanguage for denotational semantics useful both for constructing models and for proving properties of these. We do this by constructing a fairly intensional model of PCF and proving it computationally...... adequate. The model construction is related to Escardo's metric model for PCF, but here everything is carried out entirely in type theory with guarded recursion, including the formulation of the operational semantics, the model construction and the proof of adequacy....

  17. Classical conformality in the Standard Model from Coleman's theory

    CERN Document Server

    Kawana, Kiyoharu

    2016-01-01

    The classical conformality is one of the possible candidates for explaining the gauge hierarchy of the Standard Model. We show that it is naturally obtained from the Coleman's theory on baby universe.

  18. Linear control theory for gene network modeling.

    Science.gov (United States)

    Shin, Yong-Jun; Bleris, Leonidas

    2010-09-16

    Systems biology is an interdisciplinary field that aims at understanding complex interactions in cells. Here we demonstrate that linear control theory can provide valuable insight and practical tools for the characterization of complex biological networks. We provide the foundation for such analyses through the study of several case studies including cascade and parallel forms, feedback and feedforward loops. We reproduce experimental results and provide rational analysis of the observed behavior. We demonstrate that methods such as the transfer function (frequency domain) and linear state-space (time domain) can be used to predict reliably the properties and transient behavior of complex network topologies and point to specific design strategies for synthetic networks.

  19. A QCD Model Using Generalized Yang-Mills Theory

    Institute of Scientific and Technical Information of China (English)

    WANG Dian-Fu; SONG He-Shan; KOU Li-Na

    2007-01-01

    Generalized Yang-Mills theory has a covariant derivative,which contains both vector and scalar gauge bosons.Based on this theory,we construct a strong interaction model by using the group U(4).By using this U(4)generalized Yang-Mills model,we also obtain a gauge potential solution,which can be used to explain the asymptotic behavior and color confinement.

  20. Matrix models vs. Seiberg-Witten/Whitham theories

    Energy Technology Data Exchange (ETDEWEB)

    Chekhov, L.; Mironov, A

    2003-01-23

    We discuss the relation between matrix models and the Seiberg-Witten type (SW) theories, recently proposed by Dijkgraaf and Vafa. In particular, we prove that the partition function of the Hermitian one-matrix model in the planar (large N) limit coincides with the prepotential of the corresponding SW theory. This partition function is the logarithm of a Whitham {tau}-function. The corresponding Whitham hierarchy is explicitly constructed. The double-point problem is solved.

  1. Bianchi class A models in Sàez-Ballester's theory

    Science.gov (United States)

    Socorro, J.; Espinoza-García, Abraham

    2012-08-01

    We apply the Sàez-Ballester (SB) theory to Bianchi class A models, with a barotropic perfect fluid in a stiff matter epoch. We obtain exact classical solutions à la Hamilton for Bianchi type I, II and VIh=-1 models. We also find exact quantum solutions to all Bianchi Class A models employing a particular ansatz for the wave function of the universe.

  2. A Dynamic Systems Theory Model of Visual Perception Development

    Science.gov (United States)

    Coté, Carol A.

    2015-01-01

    This article presents a model for understanding the development of visual perception from a dynamic systems theory perspective. It contrasts to a hierarchical or reductionist model that is often found in the occupational therapy literature. In this proposed model vision and ocular motor abilities are not foundational to perception, they are seen…

  3. Mathematical System Theory and System Modeling

    OpenAIRE

    1980-01-01

    Choosing models related effectively to the questions to be addressed is a central issue in the craft of systems analysis. Since the mathematical description the analyst chooses constrains the types of issues he candeal with, it is important for these models to be selected so as to yield limitations that are acceptable in view of the questions the systems analysis seeks to answer. In this paper, the author gives an overview of the central issues affecting the question of model choice. To ...

  4. The Neuman Systems Model Institute: testing middle-range theories.

    Science.gov (United States)

    Gigliotti, Eileen

    2003-07-01

    The credibility of the Neuman systems model can only be established through the generation and testing of Neuman systems model-derived middle-range theories. However, due to the number and complexity of Neuman systems model concepts/concept interrelations and the diversity of middle-range theory concepts linked to these Neuman systems model concepts by researchers, no explicit middle-range theories have yet been derived from the Neuman systems model. This article describes the development of an organized program for the systematic study of the Neuman systems model. Preliminary work, already accomplished, is detailed, and a tentative plan for the completion of further preliminary work as well as beginning the actual research conduction phase is proposed.

  5. Consumer preference models: fuzzy theory approach

    Science.gov (United States)

    Turksen, I. B.; Wilson, I. A.

    1993-12-01

    Consumer preference models are widely used in new product design, marketing management, pricing and market segmentation. The purpose of this article is to develop and test a fuzzy set preference model which can represent linguistic variables in individual-level models implemented in parallel with existing conjoint models. The potential improvements in market share prediction and predictive validity can substantially improve management decisions about what to make (product design), for whom to make it (market segmentation) and how much to make (market share prediction).

  6. Measurement-based load modeling: Theory and application

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Load model is one of the most important elements in power system operation and control. However, owing to its complexity, load modeling is still an open and very difficult problem. Summarizing our work on measurement-based load modeling in China for more than twenty years, this paper systematically introduces the mathematical theory and applications regarding the load modeling. The flow chart and algorithms for measurement-based load modeling are presented. A composite load model structure with 13 parameters is also proposed. Analysis results based on the trajectory sensitivity theory indicate the importance of the load model parameters for the identification. Case studies show the accuracy of the presented measurement-based load model. The load model thus built has been validated by field measurements all over China. Future working directions on measurement- based load modeling are also discussed in the paper.

  7. Modeling in applied sciences a kinetic theory approach

    CERN Document Server

    Pulvirenti, Mario

    2000-01-01

    Modeling complex biological, chemical, and physical systems, in the context of spatially heterogeneous mediums, is a challenging task for scientists and engineers using traditional methods of analysis Modeling in Applied Sciences is a comprehensive survey of modeling large systems using kinetic equations, and in particular the Boltzmann equation and its generalizations An interdisciplinary group of leading authorities carefully develop the foundations of kinetic models and discuss the connections and interactions between model theories, qualitative and computational analysis and real-world applications This book provides a thoroughly accessible and lucid overview of the different aspects, models, computations, and methodology for the kinetic-theory modeling process Topics and Features * Integrated modeling perspective utilized in all chapters * Fluid dynamics of reacting gases * Self-contained introduction to kinetic models * Becker–Doring equations * Nonlinear kinetic models with chemical reactions * Kinet...

  8. The Family FIRO Model: The Integration of Group Theory and Family Theory.

    Science.gov (United States)

    Colangelo, Nicholas; Doherty, William J.

    1988-01-01

    Presents the Family Fundamental Interpersonal Relations Orientation (Family FIRO) Model, an integration of small-group theory and family therapy. The model is offered as a framework for organizing family issues. Discusses three fundamental issues of human relatedness and their applicability to group dynamics. (Author/NB)

  9. Modeling acquaintance networks based on balance theory

    Directory of Open Access Journals (Sweden)

    Vukašinović Vida

    2014-09-01

    Full Text Available An acquaintance network is a social structure made up of a set of actors and the ties between them. These ties change dynamically as a consequence of incessant interactions between the actors. In this paper we introduce a social network model called the Interaction-Based (IB model that involves well-known sociological principles. The connections between the actors and the strength of the connections are influenced by the continuous positive and negative interactions between the actors and, vice versa, the future interactions are more likely to happen between the actors that are connected with stronger ties. The model is also inspired by the social behavior of animal species, particularly that of ants in their colony. A model evaluation showed that the IB model turned out to be sparse. The model has a small diameter and an average path length that grows in proportion to the logarithm of the number of vertices. The clustering coefficient is relatively high, and its value stabilizes in larger networks. The degree distributions are slightly right-skewed. In the mature phase of the IB model, i.e., when the number of edges does not change significantly, most of the network properties do not change significantly either. The IB model was found to be the best of all the compared models in simulating the e-mail URV (University Rovira i Virgili of Tarragona network because the properties of the IB model more closely matched those of the e-mail URV network than the other models

  10. Theory-based Practice: Comparing and Contrasting OT Models

    DEFF Research Database (Denmark)

    Nielsen, Kristina Tomra; Berg, Brett

    2012-01-01

    Theory- Based Practice: Comparing and Contrasting OT Models The workshop will present a critical analysis of the major models of occupational therapy, A Model of Human Occupation, Enabling Occupation II, and Occupational Therapy Intervention Process Model. Similarities and differences among...... the models will be discussed, including each model’s limitations and unique contributions to the profession. Workshop format will include short lectures and group discussions....

  11. Training evaluation models: Theory and applications

    OpenAIRE

    Carbone, V.; MORVILLO, A

    2002-01-01

    This chapter has the following aims: 1. Compare the various conceptual models for evaluation, identifying their strengths and weaknesses; 2. Define an evaluation model consistent with the aims and constraints of the fit project; 3. Describe, in critical fashion, operative tools for evaluating training which are reliable, flexible and analytical.

  12. Baldrige Theory into Practice: A Generic Model

    Science.gov (United States)

    Arif, Mohammed

    2007-01-01

    Purpose: The education system globally has moved from a push-based or producer-centric system to a pull-based or customer centric system. Malcolm Baldrige Quality Award (MBQA) model happens to be one of the latest additions to the pull based models. The purpose of this paper is to develop a generic framework for MBQA that can be used by…

  13. Baldrige Theory into Practice: A Generic Model

    Science.gov (United States)

    Arif, Mohammed

    2007-01-01

    Purpose: The education system globally has moved from a push-based or producer-centric system to a pull-based or customer centric system. Malcolm Baldrige Quality Award (MBQA) model happens to be one of the latest additions to the pull based models. The purpose of this paper is to develop a generic framework for MBQA that can be used by…

  14. Measurement Models for Reasoned Action Theory.

    Science.gov (United States)

    Hennessy, Michael; Bleakley, Amy; Fishbein, Martin

    2012-03-01

    Quantitative researchers distinguish between causal and effect indicators. What are the analytic problems when both types of measures are present in a quantitative reasoned action analysis? To answer this question, we use data from a longitudinal study to estimate the association between two constructs central to reasoned action theory: behavioral beliefs and attitudes toward the behavior. The belief items are causal indicators that define a latent variable index while the attitude items are effect indicators that reflect the operation of a latent variable scale. We identify the issues when effect and causal indicators are present in a single analysis and conclude that both types of indicators can be incorporated in the analysis of data based on the reasoned action approach.

  15. Optimal transportation networks models and theory

    CERN Document Server

    Bernot, Marc; Morel, Jean-Michel

    2009-01-01

    The transportation problem can be formalized as the problem of finding the optimal way to transport a given measure into another with the same mass. In contrast to the Monge-Kantorovitch problem, recent approaches model the branched structure of such supply networks as minima of an energy functional whose essential feature is to favour wide roads. Such a branched structure is observable in ground transportation networks, in draining and irrigation systems, in electrical power supply systems and in natural counterparts such as blood vessels or the branches of trees. These lectures provide mathematical proof of several existence, structure and regularity properties empirically observed in transportation networks. The link with previous discrete physical models of irrigation and erosion models in geomorphology and with discrete telecommunication and transportation models is discussed. It will be mathematically proven that the majority fit in the simple model sketched in this volume.

  16. Quantum Field Theory and the Electroweak Standard Model

    CERN Document Server

    Boos, E

    2015-01-01

    The Standard Model is one of the main intellectual achievements for about the last 50 years, a result of many theoretical and experimental studies. In this lecture a brief introduction to the electroweak part of the Standard Model is given. Since the Standard Model is a quantum field theory, some aspects for understanding of quantization of abelian and non-abelian gauge theories are also briefly discussed. It is demonstrated how well the electroweak Standard Model works in describing a large variety of precise experimental measure- ments at lepton and hadron collider.

  17. Sticker DNA computer model--Part Ⅰ:Theory

    Institute of Scientific and Technical Information of China (English)

    XU Jin; DONG Yafei; WEI Xiaopeng

    2004-01-01

    Sticker model is one of the basic models in the DNA computer models. This model is coded with single-double stranded DNA molecules. It has the following advantages that the operations require no strands extension and use no enzymes; What's more, the materials are reusable. Therefore it arouses attention and interest of scientists in many fields. In this paper, we will systematically analyze the theories and applications of the model, summarize other scientists' contributions in this field, and propose our research results. This paper is the theoretical portion of the sticker model on DNA computer, which includes the introduction of the basic model of sticker computing. Firstly, we systematically introduce the basic theories of classic models about sticker computing; Secondly, we discuss the sticker system which is an abstract computing model based on the sticker model and formal languages; Finally, extend and perfect the model, and present two types of models that are more extensive in the applications and more perfect in the theory than the past models: one is the so-called k-bit sticker model, the other is full-message sticker DNA computing model.

  18. Theory of stellar convection II: first stellar models

    CERN Document Server

    Pasetto, S; Chiosi, E; Cropper, M; Weiss, A

    2015-01-01

    We present here the first stellar models on the Hertzsprung-Russell diagram (HRD), in which convection is treated according to the novel scale-free convection theory (SFC theory) by Pasetto et al. (2014). The aim is to compare the results of the new theory with those from the classical, calibrated mixing-length (ML) theory to examine differences and similarities. We integrate the equations describing the structure of the atmosphere from the stellar surface down to a few percent of the stellar mass using both ML theory and SFC theory. The key temperature over pressure gradients, the energy fluxes, and the extension of the convective zones are compared in both theories. The analysis is first made for the Sun and then extended to other stars of different mass and evolutionary stage. The results are adequate: the SFC theory yields convective zones, temperature gradients of the ambient and of the convective element, and energy fluxes that are very similar to those derived from the "calibrated" MT theory for main s...

  19. Mixed models theory and applications with R

    CERN Document Server

    Demidenko, Eugene

    2013-01-01

    Mixed modeling is one of the most promising and exciting areas of statistical analysis, enabling the analysis of nontraditional, clustered data that may come in the form of shapes or images. This book provides in-depth mathematical coverage of mixed models' statistical properties and numerical algorithms, as well as applications such as the analysis of tumor regrowth, shape, and image. The new edition includes significant updating, over 300 exercises, stimulating chapter projects and model simulations, inclusion of R subroutines, and a revised text format. The target audience continues to be g

  20. Solid mechanics theory, modeling, and problems

    CERN Document Server

    Bertram, Albrecht

    2015-01-01

    This textbook offers an introduction to modeling the mechanical behavior of solids within continuum mechanics and thermodynamics. To illustrate the fundamental principles, the book starts with an overview of the most important models in one dimension. Tensor calculus, which is called for in three-dimensional modeling, is concisely presented in the second part of the book. Once the reader is equipped with these essential mathematical tools, the third part of the book develops the foundations of continuum mechanics right from the beginning. Lastly, the book’s fourth part focuses on modeling the mechanics of materials and in particular elasticity, viscoelasticity and plasticity. Intended as an introductory textbook for students and for professionals interested in self-study, it also features numerous worked-out examples to aid in understanding.

  1. Matrix Models, Topological Strings, and Supersymmetric Gauge Theories

    CERN Document Server

    Dijkgraaf, R; Dijkgraaf, Robbert; Vafa, Cumrun

    2002-01-01

    We show that B-model topological strings on local Calabi-Yau threefolds are large N duals of matrix models, which in the planar limit naturally give rise to special geometry. These matrix models directly compute F-terms in an associated N=1 supersymmetric gauge theory, obtained by deforming N=2 theories by a superpotential term that can be directly identified with the potential of the matrix model. Moreover by tuning some of the parameters of the geometry in a double scaling limit we recover (p,q) conformal minimal models coupled to 2d gravity, thereby relating non-critical string theories to type II superstrings on Calabi-Yau backgrounds.

  2. Matrix models, topological strings, and supersymmetric gauge theories

    Energy Technology Data Exchange (ETDEWEB)

    Dijkgraaf, Robbert E-mail: rhd@science.uva.nl; Vafa, Cumrun

    2002-11-11

    We show that B-model topological strings on local Calabi-Yau threefolds are large-N duals of matrix models, which in the planar limit naturally give rise to special geometry. These matrix models directly compute F-terms in an associated N=1 supersymmetric gauge theory, obtained by deforming N=2 theories by a superpotential term that can be directly identified with the potential of the matrix model. Moreover by tuning some of the parameters of the geometry in a double scaling limit we recover (p,q) conformal minimal models coupled to 2d gravity, thereby relating non-critical string theories to type II superstrings on Calabi-Yau backgrounds.

  3. Modeling workplace bullying using catastrophe theory.

    Science.gov (United States)

    Escartin, J; Ceja, L; Navarro, J; Zapf, D

    2013-10-01

    Workplace bullying is defined as negative behaviors directed at organizational members or their work context that occur regularly and repeatedly over a period of time. Employees' perceptions of psychosocial safety climate, workplace bullying victimization, and workplace bullying perpetration were assessed within a sample of nearly 5,000 workers. Linear and nonlinear approaches were applied in order to model both continuous and sudden changes in workplace bullying. More specifically, the present study examines whether a nonlinear dynamical systems model (i.e., a cusp catastrophe model) is superior to the linear combination of variables for predicting the effect of psychosocial safety climate and workplace bullying victimization on workplace bullying perpetration. According to the AICc, and BIC indices, the linear regression model fits the data better than the cusp catastrophe model. The study concludes that some phenomena, especially unhealthy behaviors at work (like workplace bullying), may be better studied using linear approaches as opposed to nonlinear dynamical systems models. This can be explained through the healthy variability hypothesis, which argues that positive organizational behavior is likely to present nonlinear behavior, while a decrease in such variability may indicate the occurrence of negative behaviors at work.

  4. Theory and modeling of electron fishbones

    Science.gov (United States)

    Vlad, G.; Fusco, V.; Briguglio, S.; Fogaccia, G.; Zonca, F.; Wang, X.

    2016-10-01

    Internal kink instabilities exhibiting fishbone like behavior have been observed in a variety of experiments where a high energy electron population, generated by strong auxiliary heating and/or current drive systems, was present. After briefly reviewing the experimental evidences of energetic electrons driven fishbones, and the main results of linear and nonlinear theory of electron fishbones, the results of global, self-consistent, nonlinear hybrid MHD-Gyrokinetic simulations will be presented. To this purpose, the extended/hybrid MHD-Gyrokinetic code XHMGC will be used. Linear dynamics analysis will enlighten the effect of considering kinetic thermal ion compressibility and diamagnetic response, and kinetic thermal electrons compressibility, in addition to the energetic electron contribution. Nonlinear saturation and energetic electron transport will also be addressed, making extensive use of Hamiltonian mapping techniques, discussing both centrally peaked and off-axis peaked energetic electron profiles. It will be shown that centrally peaked energetic electron profiles are characterized by resonant excitation and nonlinear response of deeply trapped energetic electrons. On the other side, off-axis peaked energetic electron profiles are characterized by resonant excitation and nonlinear response of barely circulating energetic electrons which experience toroidal precession reversal of their motion.

  5. Spatial interaction models facility location using game theory

    CERN Document Server

    D'Amato, Egidio; Pardalos, Panos

    2017-01-01

    Facility location theory develops the idea of locating one or more facilities by optimizing suitable criteria such as minimizing transportation cost, or capturing the largest market share. The contributions in this book focus an approach to facility location theory through game theoretical tools highlighting situations where a location decision is faced by several decision makers and leading to a game theoretical framework in non-cooperative and cooperative methods. Models and methods regarding the facility location via game theory are explored and applications are illustrated through economics, engineering, and physics. Mathematicians, engineers, economists and computer scientists working in theory, applications and computational aspects of facility location problems using game theory will find this book useful.

  6. Electrorheological fluids modeling and mathematical theory

    CERN Document Server

    Růžička, Michael

    2000-01-01

    This is the first book to present a model, based on rational mechanics of electrorheological fluids, that takes into account the complex interactions between the electromagnetic fields and the moving liquid. Several constitutive relations for the Cauchy stress tensor are discussed. The main part of the book is devoted to a mathematical investigation of a model possessing shear-dependent viscosities, proving the existence and uniqueness of weak and strong solutions for the steady and the unsteady case. The PDS systems investigated possess so-called non-standard growth conditions. Existence results for elliptic systems with non-standard growth conditions and with a nontrivial nonlinear r.h.s. and the first ever results for parabolic systems with a non-standard growth conditions are given for the first time. Written for advanced graduate students, as well as for researchers in the field, the discussion of both the modeling and the mathematics is self-contained.

  7. A catastrophe theory model of the conflict helix, with tests.

    Science.gov (United States)

    Rummel, R J

    1987-10-01

    Macro social field theory has undergone extensive development and testing since the 1960s. One of these has been the articulation of an appropriate conceptual micro model--called the conflict helix--for understanding the process from conflict to cooperation and vice versa. Conflict and cooperation are viewed as distinct equilibria of forces in a social field; the movement between these equilibria is a jump, energized by a gap between social expectations and power, and triggered by some minor event. Quite independently, there also has been much recent application of catastrophe theory to social behavior, but usually without a clear substantive theory and lacking empirical testing. This paper uses catastrophe theory--namely, the butterfly model--mathematically to structure the conflict helix. The social field framework and helix provide the substantive interpretation for the catastrophe theory; and catastrophe theory provides a suitable mathematical model for the conflict helix. The model is tested on the annual conflict and cooperation between India and Pakistan, 1948 to 1973. The results are generally positive and encouraging.

  8. Mean field theory, topological field theory, and multi-matrix models

    Energy Technology Data Exchange (ETDEWEB)

    Dijkgraaf, R. (Princeton Univ., NJ (USA). Joseph Henry Labs.); Witten, E. (Institute for Advanced Study, Princeton, NJ (USA). School of Natural Sciences)

    1990-10-08

    We show that the genus zero correlation functions of an arbitrary topological field theory coupled to two-dimensional topological gravity are determined by an appropriate Landau-Ginzburg potential. We determine the potentials that arise for topological sigma models with CP{sup 1} or a Calabi-Yau manifold for target space. We present substantial evidence that the multi-matrix models that have been studied recently are equivalent to certain topological field theories coupled to topological gravity. We also describe a topological version of the general 'string equation'. (orig.).

  9. Mean field theory, topological field theory, and multi-matrix models

    Science.gov (United States)

    Dijkgraaf, Robbert; Witten, Edward

    1990-10-01

    We show that the genus zero correlation functions of an arbitrary topological field theory coupled to two-dimensional topological gravity are determined by an appropriate Landau-Ginzburg potential. We determine the potentials that arise for topological sigma models with CP 1 or a Calabi-Yau manifold for target space. We present substantial evidence that the multi-matrix models that have been studied recently are equivalent to certain topological field theories coupled to topological gravity. We also describe a topological version of the general "string equation".

  10. Theory and Model for Martensitic Transformations

    DEFF Research Database (Denmark)

    Lindgård, Per-Anker; Mouritsen, Ole G.

    1986-01-01

    Martensitic transformations are shown to be driven by the interplay between two fluctuating strain components. No soft mode is needed, but a central peak occurs representing the dynamics of strain clusters. A two-dimensional magnetic-analog model with the martensitic-transition symmetry...

  11. Markov models of aging: theory and practice.

    Science.gov (United States)

    Steinsaltz, David; Mohan, Gurjinder; Kolb, Martin

    2012-10-01

    We review and structure some of the mathematical and statistical models that have been developed over the past half century to grapple with theoretical and experimental questions about the stochastic development of aging over the life course. We suggest that the mathematical models are in large part addressing the problem of partitioning the randomness in aging: How does aging vary between individuals, and within an individual over the lifecourse? How much of the variation is inherently related to some qualities of the individual, and how much is entirely random? How much of the randomness is cumulative, and how much is merely short-term flutter? We propose that recent lines of statistical inquiry in survival analysis could usefully grapple with these questions, all the more so if they were more explicitly linked to the relevant mathematical and biological models of aging. To this end, we describe points of contact among the various lines of mathematical and statistical research. We suggest some directions for future work, including the exploration of information-theoretic measures for evaluating components of stochastic models as the basis for analyzing experiments and anchoring theoretical discussions of aging. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Study on Strand Space Model Theory

    Institute of Scientific and Technical Information of China (English)

    JI QingGuang(季庆光); QING SiHan(卿斯汉); ZHOU YongBin(周永彬); FENG DengGuo(冯登国)

    2003-01-01

    The growing interest in the application of formal methods of cryptographic pro-tocol analysis has led to the development of a number of different ways for analyzing protocol. Inthis paper, it is strictly proved that if for any strand, there exists at least one bundle containingit, then an entity authentication protocol is secure in strand space model (SSM) with some smallextensions. Unfortunately, the results of attack scenario demonstrate that this protocol and the Yahalom protocol and its modification are de facto insecure. By analyzing the reasons of failure offormal inference in strand space model, some deficiencies in original SSM are pointed out. In orderto break through these limitations of analytic capability of SSM, the generalized strand space model(GSSM) induced by some protocol is proposed. In this model, some new classes of strands, oraclestrands, high order oracle strands etc., are developed, and some notions are formalized strictly in GSSM, such as protocol attacks, valid protocol run and successful protocol run. GSSM can thenbe used to further analyze the entity authentication protocol. This analysis sheds light on why thisprotocol would be vulnerable while it illustrates that GSSM not only can prove security protocolcorrect, but also can be efficiently used to construct protocol attacks. It is also pointed out thatusing other protocol to attack some given protocol is essentially the same as the case of using themost of protocol itself.

  13. Modeling Environmental Concern: Theory and Application.

    Science.gov (United States)

    Hackett, Paul M. W.

    1993-01-01

    Human concern for the quality and protection of the natural environment forms the basis of successful environmental conservation activities. Considers environmental concern research and proposes a model that incorporates the multiple dimensions of research through which environmental concern may be evaluated. (MDH)

  14. L∞-algebra models and higher Chern-Simons theories

    Science.gov (United States)

    Ritter, Patricia; Sämann, Christian

    2016-10-01

    We continue our study of zero-dimensional field theories in which the fields take values in a strong homotopy Lie algebra. In the first part, we review in detail how higher Chern-Simons theories arise in the AKSZ-formalism. These theories form a universal starting point for the construction of L∞-algebra models. We then show how to describe superconformal field theories and how to perform dimensional reductions in this context. In the second part, we demonstrate that Nambu-Poisson and multisymplectic manifolds are closely related via their Heisenberg algebras. As a byproduct of our discussion, we find central Lie p-algebra extensions of 𝔰𝔬(p + 2). Finally, we study a number of L∞-algebra models which are physically interesting and which exhibit quantized multisymplectic manifolds as vacuum solutions.

  15. Rock mechanics modeling based on soft granulation theory

    CERN Document Server

    Owladeghaffari, H

    2008-01-01

    This paper describes application of information granulation theory, on the design of rock engineering flowcharts. Firstly, an overall flowchart, based on information granulation theory has been highlighted. Information granulation theory, in crisp (non-fuzzy) or fuzzy format, can take into account engineering experiences (especially in fuzzy shape-incomplete information or superfluous), or engineering judgments, in each step of designing procedure, while the suitable instruments modeling are employed. In this manner and to extension of soft modeling instruments, using three combinations of Self Organizing Map (SOM), Neuro-Fuzzy Inference System (NFIS), and Rough Set Theory (RST) crisp and fuzzy granules, from monitored data sets are obtained. The main underlined core of our algorithms are balancing of crisp(rough or non-fuzzy) granules and sub fuzzy granules, within non fuzzy information (initial granulation) upon the open-close iterations. Using different criteria on balancing best granules (information pock...

  16. Applying learning theories and instructional design models for effective instruction.

    Science.gov (United States)

    Khalil, Mohammed K; Elkhider, Ihsan A

    2016-06-01

    Faculty members in higher education are involved in many instructional design activities without formal training in learning theories and the science of instruction. Learning theories provide the foundation for the selection of instructional strategies and allow for reliable prediction of their effectiveness. To achieve effective learning outcomes, the science of instruction and instructional design models are used to guide the development of instructional design strategies that elicit appropriate cognitive processes. Here, the major learning theories are discussed and selected examples of instructional design models are explained. The main objective of this article is to present the science of learning and instruction as theoretical evidence for the design and delivery of instructional materials. In addition, this article provides a practical framework for implementing those theories in the classroom and laboratory. Copyright © 2016 The American Physiological Society.

  17. Automated Physico-Chemical Cell Model Development through Information Theory

    Energy Technology Data Exchange (ETDEWEB)

    Peter J. Ortoleva

    2005-11-29

    The objective of this project was to develop predictive models of the chemical responses of microbial cells to variations in their surroundings. The application of these models is optimization of environmental remediation and energy-producing biotechnical processes.The principles on which our project is based are as follows: chemical thermodynamics and kinetics; automation of calibration through information theory; integration of multiplex data (e.g. cDNA microarrays, NMR, proteomics), cell modeling, and bifurcation theory to overcome cellular complexity; and the use of multiplex data and information theory to calibrate and run an incomplete model. In this report we review four papers summarizing key findings and a web-enabled, multiple module workflow we have implemented that consists of a set of interoperable systems biology computational modules.

  18. From integrable models to gauge theories Festschrift Matinyan (Sergei G)

    CERN Document Server

    Gurzadyan, V G

    2002-01-01

    This collection of twenty articles in honor of the noted physicist and mentor Sergei Matinyan focuses on topics that are of fundamental importance to high-energy physics, field theory and cosmology. The topics range from integrable quantum field theories, three-dimensional Ising models, parton models and tests of the Standard Model, to black holes in loop quantum gravity, the cosmological constant and magnetic fields in cosmology. A pedagogical essay by Lev Okun concentrates on the problem of fundamental units. The articles have been written by well-known experts and are addressed to graduate

  19. Spectral and scattering theory for translation invariant models in quantum field theory

    DEFF Research Database (Denmark)

    Rasmussen, Morten Grud

    This thesis is concerned with a large class of massive translation invariant models in quantum field theory, including the Nelson model and the Fröhlich polaron. The models in the class describe a matter particle, e.g. a nucleon or an electron, linearly coupled to a second quantised massive scalar...... of the essential energy-momentum spectrum and either the two-body threshold, if there are no exited isolated mass shells, or the one-body threshold pertaining to the first exited isolated mass shell, if it exists. For the model restricted to the vacuum and one-particle sectors, the absence of singular continuous...... spectrum is proven to hold globally and scattering theory of the model is studied using time-dependent methods, of which the main result is asymptotic completeness....

  20. Chiral field theories as models for hadron substructure

    Energy Technology Data Exchange (ETDEWEB)

    Kahana, S.H.

    1987-03-01

    A model for the nucleon as soliton of quarks interacting with classical meson fields is described. The theory, based on the linear sigma model, is renormalizable and capable of including sea quarks straightforwardly. Application to nuclear matter is made in a Wigner-Seitz approximation.

  1. Pilot evaluation in TENCompetence: a theory-driven model1

    NARCIS (Netherlands)

    J. Schoonenboom; H. Sligte; A. Moghnieh; M. Specht; C. Glahn; K. Stefanov

    2008-01-01

    This paper describes a theory-driven evaluation model that is used in evaluating four pilots in which an infrastructure for lifelong competence development, which is currently being developed, is validated. The model makes visible the separate implementation steps that connect the envisaged infrastr

  2. Reciprocal Ontological Models Show Indeterminism Comparable to Quantum Theory

    Science.gov (United States)

    Bandyopadhyay, Somshubhro; Banik, Manik; Bhattacharya, Some Sankar; Ghosh, Sibasish; Kar, Guruprasad; Mukherjee, Amit; Roy, Arup

    2016-12-01

    We show that within the class of ontological models due to Harrigan and Spekkens, those satisfying preparation-measurement reciprocity must allow indeterminism comparable to that in quantum theory. Our result implies that one can design quantum random number generator, for which it is impossible, even in principle, to construct a reciprocal deterministic model.

  3. Reciprocal Ontological Models Show Indeterminism Comparable to Quantum Theory

    Science.gov (United States)

    Bandyopadhyay, Somshubhro; Banik, Manik; Bhattacharya, Some Sankar; Ghosh, Sibasish; Kar, Guruprasad; Mukherjee, Amit; Roy, Arup

    2017-02-01

    We show that within the class of ontological models due to Harrigan and Spekkens, those satisfying preparation-measurement reciprocity must allow indeterminism comparable to that in quantum theory. Our result implies that one can design quantum random number generator, for which it is impossible, even in principle, to construct a reciprocal deterministic model.

  4. Kinetic theories for spin models for cooperative relaxation dynamics

    Science.gov (United States)

    Pitts, Steven Jerome

    The facilitated kinetic Ising models with asymmetric spin flip constraints introduced by Jackle and co-workers [J. Jackle, S. Eisinger, Z. Phys. B 84, 115 (1991); J. Reiter, F. Mauch, J. Jackle, Physica A 184, 458 (1992)] exhibit complex relaxation behavior in their associated spin density time correlation functions. This includes the growth of relaxation times over many orders of magnitude when the thermodynamic control parameter is varied, and, in some cases, ergodic-nonergodic transitions. Relaxation equations for the time dependence of the spin density autocorrelation function for a set of these models are developed that relate this autocorrelation function to the irreducible memory function of Kawasaki [K. Kawasaki, Physica A 215, 61 (1995)] using a novel diagrammatic series approach. It is shown that the irreducible memory function in a theory of the relaxation of an autocorrelation function in a Markov model with detailed balance plays the same role as the part of the memory function approximated by a polynomial function of the autocorrelation function with positive coefficients in schematic simple mode coupling theories for supercooled liquids [W. Gotze, in Liquids, Freezing and the Glass Transition, D. Levesque, J. P. Hansen, J. Zinn-Justin eds., 287 (North Holland, New York, 1991)]. Sets of diagrams in the series for the irreducible memory function are summed which lead to approximations of this type. The behavior of these approximations is compared with known results from previous analytical calculations and from numerical simulations. For the simplest one dimensional model, relaxation equations that are closely related to schematic extended mode coupling theories [W. Gotze, ibid] are also derived using the diagrammatic series. Comparison of the results of these approximate theories with simulation data shows that these theories improve significantly on the results of the theories of the simple schematic mode coupling theory type. The potential

  5. The origin of discrete symmetries in F-theory models

    OpenAIRE

    2015-01-01

    While non-abelian groups are undoubtedly the cornerstone of Grand Unified Theories (GUTs), phenomenology shows that the role of abelian and discrete symmetries is equally important in model building. The latter are the appropriate tool to suppress undesired proton decay operators and various flavour violating interactions, to generate a hierarchical fermion mass spectrum, etc. In F-theory, GUT symmetries are linked to the singularities of the elliptically fibred K3 manifolds; they are of ADE ...

  6. Lenses on reading an introduction to theories and models

    CERN Document Server

    Tracey, Diane H

    2017-01-01

    Widely adopted as an ideal introduction to the major models of reading, this text guides students to understand and facilitate children's literacy development. Coverage encompasses the full range of theories that have informed reading instruction and research, from classical thinking to cutting-edge cognitive, social learning, physiological, and affective perspectives. Readers learn how theory shapes instructional decision making and how to critically evaluate the assumptions and beliefs that underlie their own teaching. Pedagogical features include framing and discussion questions, learning a

  7. Fuzzy Stochastic Optimization Theory, Models and Applications

    CERN Document Server

    Wang, Shuming

    2012-01-01

    Covering in detail both theoretical and practical perspectives, this book is a self-contained and systematic depiction of current fuzzy stochastic optimization that deploys the fuzzy random variable as a core mathematical tool to model the integrated fuzzy random uncertainty. It proceeds in an orderly fashion from the requisite theoretical aspects of the fuzzy random variable to fuzzy stochastic optimization models and their real-life case studies.   The volume reflects the fact that randomness and fuzziness (or vagueness) are two major sources of uncertainty in the real world, with significant implications in a number of settings. In industrial engineering, management and economics, the chances are high that decision makers will be confronted with information that is simultaneously probabilistically uncertain and fuzzily imprecise, and optimization in the form of a decision must be made in an environment that is doubly uncertain, characterized by a co-occurrence of randomness and fuzziness. This book begins...

  8. Nonlinear model predictive control theory and algorithms

    CERN Document Server

    Grüne, Lars

    2017-01-01

    This book offers readers a thorough and rigorous introduction to nonlinear model predictive control (NMPC) for discrete-time and sampled-data systems. NMPC schemes with and without stabilizing terminal constraints are detailed, and intuitive examples illustrate the performance of different NMPC variants. NMPC is interpreted as an approximation of infinite-horizon optimal control so that important properties like closed-loop stability, inverse optimality and suboptimality can be derived in a uniform manner. These results are complemented by discussions of feasibility and robustness. An introduction to nonlinear optimal control algorithms yields essential insights into how the nonlinear optimization routine—the core of any nonlinear model predictive controller—works. Accompanying software in MATLAB® and C++ (downloadable from extras.springer.com/), together with an explanatory appendix in the book itself, enables readers to perform computer experiments exploring the possibilities and limitations of NMPC. T...

  9. Computational hemodynamics theory, modelling and applications

    CERN Document Server

    Tu, Jiyuan; Wong, Kelvin Kian Loong

    2015-01-01

    This book discusses geometric and mathematical models that can be used to study fluid and structural mechanics in the cardiovascular system.  Where traditional research methodologies in the human cardiovascular system are challenging due to its invasive nature, several recent advances in medical imaging and computational fluid and solid mechanics modelling now provide new and exciting research opportunities. This emerging field of study is multi-disciplinary, involving numerical methods, computational science, fluid and structural mechanics, and biomedical engineering. Certainly any new student or researcher in this field may feel overwhelmed by the wide range of disciplines that need to be understood. This unique book is one of the first to bring together knowledge from multiple disciplines, providing a starting point to each of the individual disciplines involved, attempting to ease the steep learning curve. This book presents elementary knowledge on the physiology of the cardiovascular system; basic knowl...

  10. Theory and Model of Agricultural Insurance Subsidy

    Institute of Scientific and Technical Information of China (English)

    Wan Kailiang; Long Wenjun

    2007-01-01

    The issue of agricultural insurance subsidy is discussed in this paper aiming to make it provided more rationally and scientifically.It is started with the connection between agricultural insurance and financial subsidy.It is really necessary and crucial to implement the financial insurance due to the bad operational performance,especially in the developing countries.But the subsidy should be provided more rationally because financial subsidy has lots of negative effects.A model in competitive insurance markets developed by Ahsan et al(1982)and a farmers'decision model arc developed to solve the optimal subsidized rate.Finally,the equation is got to calculate it.But a quantitative subsidized rate is not made here because the calculation should be under some restricted conditions,which are always absent in the developing countries.So the government should provide some subsidy for the ex ante research and preparation to get the scientific probability and premium rate.

  11. Network Data: Statistical Theory and New Models

    Science.gov (United States)

    2016-02-17

    Using AERONET DRAGON Campaign Data, IEEE Transactions on Geoscience and Remote Sensing, (08 2015): 0. doi: 10.1109/TGRS.2015.2395722 Geoffrey...are not viable, i.e. the fruit fly dies after the knock-out of the gene. Further examination of the ftz stained embryos indicates that the lack of...our approach for spatial gene expression analysis for early stage fruit fly embryos, we are in a process to extend it to model later stage gene

  12. Debris Discs: Modeling/theory review

    Science.gov (United States)

    Thébault, P.

    2012-03-01

    An impressive amount of photometric, spectroscopic and imaging observations of circumstellar debris discs has been accumulated over the past 3 decades, revealing that they come in all shapes and flavours, from young post-planet-formation systems like Beta-Pic to much older ones like Vega. What we see in these systems are small grains, which are probably only the tip of the iceberg of a vast population of larger (undetectable) collisionally-eroding bodies, leftover from the planet-formation process. Understanding the spatial structure, physical properties, origin and evolution of this dust is of crucial importance, as it is our only window into what is going on in these systems. Dust can be used as a tracer of the distribution of their collisional progenitors and of possible hidden massive pertubers, but can also allow to derive valuable information about the disc's total mass, size distribution or chemical composition. I will review the state of the art in numerical models of debris disc, and present some important issues that are explored by current modelling efforts: planet-disc interactions, link between cold (i.e. Herschel-observed) and hot discs, effect of binarity, transient versus continuous processes, etc. I will finally present some possible perspectives for the development of future models.

  13. A class of effective field theory models of cosmic acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Bloomfield, Jolyon K.; Flanagan, Éanna É., E-mail: jkb84@cornell.edu, E-mail: eef3@cornell.edu [Center for Radiophysics and Space Research, Cornell University, Space Science Building, Ithaca, NY 14853 (United States)

    2012-10-01

    We explore a class of effective field theory models of cosmic acceleration involving a metric and a single scalar field. These models can be obtained by starting with a set of ultralight pseudo-Nambu-Goldstone bosons whose couplings to matter satisfy the weak equivalence principle, assuming that one boson is lighter than all the others, and integrating out the heavier fields. The result is a quintessence model with matter coupling, together with a series of correction terms in the action in a covariant derivative expansion, with specific scalings for the coefficients. After eliminating higher derivative terms and exploiting the field redefinition freedom, we show that the resulting theory contains nine independent free functions of the scalar field when truncated at four derivatives. This is in contrast to the four free functions found in similar theories of single-field inflation, where matter is not present. We discuss several different representations of the theory that can be obtained using the field redefinition freedom. For perturbations to the quintessence field today on subhorizon lengthscales larger than the Compton wavelength of the heavy fields, the theory is weakly coupled and natural in the sense of t'Hooft. The theory admits a regime where the perturbations become modestly nonlinear, but very strong nonlinearities lie outside its domain of validity.

  14. Nanofluid Drop Evaporation: Experiment, Theory, and Modeling

    Science.gov (United States)

    Gerken, William James

    Nanofluids, stable colloidal suspensions of nanoparticles in a base fluid, have potential applications in the heat transfer, combustion and propulsion, manufacturing, and medical fields. Experiments were conducted to determine the evaporation rate of room temperature, millimeter-sized pendant drops of ethanol laden with varying amounts (0-3% by weight) of 40-60 nm aluminum nanoparticles (nAl). Time-resolved high-resolution drop images were collected for the determination of early-time evaporation rate (D2/D 02 > 0.75), shown to exhibit D-square law behavior, and surface tension. Results show an asymptotic decrease in pendant drop evaporation rate with increasing nAl loading. The evaporation rate decreases by approximately 15% at around 1% to 3% nAl loading relative to the evaporation rate of pure ethanol. Surface tension was observed to be unaffected by nAl loading up to 3% by weight. A model was developed to describe the evaporation of the nanofluid pendant drops based on D-square law analysis for the gas domain and a description of the reduction in liquid fraction available for evaporation due to nanoparticle agglomerate packing near the evaporating drop surface. Model predictions are in relatively good agreement with experiment, within a few percent of measured nanofluid pendant drop evaporation rate. The evaporation of pinned nanofluid sessile drops was also considered via modeling. It was found that the same mechanism for nanofluid evaporation rate reduction used to explain pendant drops could be used for sessile drops. That mechanism is a reduction in evaporation rate due to a reduction in available ethanol for evaporation at the drop surface caused by the packing of nanoparticle agglomerates near the drop surface. Comparisons of the present modeling predictions with sessile drop evaporation rate measurements reported for nAl/ethanol nanofluids by Sefiane and Bennacer [11] are in fairly good agreement. Portions of this abstract previously appeared as: W. J

  15. Invisible 'glue' bosons in model field theory

    CERN Document Server

    Shirokov, M I

    2002-01-01

    Fermionic psi(x) and bosonic phi(x) fields with vector coupling are discussed. It is shown that 'clothed' bosons of the model do not interact with fermions and between themselves. If phi(x) does not interact with other fields of the particle physics, then the 'clothed' bosons have properties of the cosmological 'dark' matter': they cannot be detected in Earth's laboratories. This cause of the boson invisibility contrasts with the origin of the unobservability of the isolated gluons in QCD which is explained by the confinement of colour

  16. Putting "Organizations" into an Organization Theory Course: A Hybrid CAO Model for Teaching Organization Theory

    Science.gov (United States)

    Hannah, David R.; Venkatachary, Ranga

    2010-01-01

    In this article, the authors present a retrospective analysis of an instructor's multiyear redesign of a course on organization theory into what is called a hybrid Classroom-as-Organization model. It is suggested that this new course design served to apprentice students to function in quasi-real organizational structures. The authors further argue…

  17. Bouncing Model in Brane World Theory

    CERN Document Server

    Maier, Rodrigo; Soares, Ivano Damião

    2013-01-01

    We examine the nonlinear dynamics of a closed Friedmann-Robertson-Walker universe in the framework of Brane World formalism with a timelike extra dimension. In this scenario, the Friedmann equations contain additional terms arising from the bulk-brane interaction which provide a concrete model for nonsingular bounces in the early phase of the Universe. We construct a nonsingular cosmological scenario sourced with dust, radiation and a cosmological constant. The structure of the phase space shows a nonsingular orbit with two accelerated phases, separated by a smooth transition corresponding to a decelerated expansion. Given observational parameters we connect such phases to a primordial accelerated phase, a soft transition to Friedmann (where the classical regime is valid), and a graceful exit to a de Sitter accelerated phase.

  18. Scaling Theory and Modeling of DNA Evolution

    Science.gov (United States)

    Buldyrev, Sergey V.

    1998-03-01

    We present evidence supporting the possibility that the nucleotide sequence in noncoding DNA is power-law correlated. We do not find such long-range correlation in the coding regions of the gene, so we build a ``coding sequence finder'' to locate the coding regions of an unknown DNA sequence. We also propose a different coding sequence finding algorithm, based on the concept of mutual information(I. Große, S. V. Buldyrev, H. Herzel, H. E. Stanley, (preprint).). We describe our recent work on quantification of DNA patchiness, using long-range correlation measures (G. M. Viswanathan, S. V. Buldyrev, S. Havlin, and H. E. Stanley, Biophysical Journal 72), 866-875 (1997).. We also present our recent study of the simple repeat length distributions. We find that the distributions of some simple repeats in noncoding DNA have long power-law tails, while in coding DNA all simple repeat distributions decay exponentially. (N. V. Dokholyan, S. V. Buldyrev, S. Havlin, and H. E. Stanley, Phys. Rev. Lett (in press).) We discuss several models based on insertion-deletion and mutation-duplication mechanisms that relate long-range correlations in non-coding DNA to DNA evolution. Specifically, we relate long-range correlations in non-coding DNA to simple repeat expansion, and propose an evolutionary model that reproduces the power law distribution of simple repeat lengths. We argue that the absence of long-range correlations in protein coding sequences is related to their highly conserved primary structure which is necessary to insure protein folding.

  19. An Abstraction Theory for Qualitative Models of Biological Systems

    CERN Document Server

    Banks, Richard; 10.4204/EPTCS.40.3

    2010-01-01

    Multi-valued network models are an important qualitative modelling approach used widely by the biological community. In this paper we consider developing an abstraction theory for multi-valued network models that allows the state space of a model to be reduced while preserving key properties of the model. This is important as it aids the analysis and comparison of multi-valued networks and in particular, helps address the well-known problem of state space explosion associated with such analysis. We also consider developing techniques for efficiently identifying abstractions and so provide a basis for the automation of this task. We illustrate the theory and techniques developed by investigating the identification of abstractions for two published MVN models of the lysis-lysogeny switch in the bacteriophage lambda.

  20. Summary of papers presented in the Theory and Modelling session

    Directory of Open Access Journals (Sweden)

    Lin-Liu Y.R.

    2012-09-01

    Full Text Available A total of 14 contributions were presented in the Theory and Modelling sessions at EC-17. One Theory and Modelling paper was included in the ITER ECRH and ECE sessions each. Three papers were in the area of nonlinear physics discussing parametric processes accompanying ECRH. Eight papers were based on the quasi-linear theory of wave heating and current drive. Three of these addressed the application of ECCD for NTM stabilization. Two papers considered scattering of EC waves by edge density fluctuations and related phenomena. In this summary, we briefly describe the highlights of these contributions. Finally, the three papers concerning modelling of various aspects of ECE are reported in the ECE session.

  1. Modeling Reusable and Interoperable Faceted Browsing Systems with Category Theory.

    Science.gov (United States)

    Harris, Daniel R

    2015-08-01

    Faceted browsing has become ubiquitous with modern digital libraries and online search engines, yet the process is still difficult to abstractly model in a manner that supports the development of interoperable and reusable interfaces. We propose category theory as a theoretical foundation for faceted browsing and demonstrate how the interactive process can be mathematically abstracted. Existing efforts in facet modeling are based upon set theory, formal concept analysis, and lightweight ontologies, but in many regards, they are implementations of faceted browsing rather than a specification of the basic, underlying structures and interactions. We will demonstrate that category theory allows us to specify faceted objects and study the relationships and interactions within a faceted browsing system. Implementations can then be constructed through a category-theoretic lens using these models, allowing abstract comparison and communication that naturally support interoperability and reuse.

  2. Foundations of reusable and interoperable facet models using category theory.

    Science.gov (United States)

    Harris, Daniel R

    2016-10-01

    Faceted browsing has become ubiquitous with modern digital libraries and online search engines, yet the process is still difficult to abstractly model in a manner that supports the development of interoperable and reusable interfaces. We propose category theory as a theoretical foundation for faceted browsing and demonstrate how the interactive process can be mathematically abstracted. Existing efforts in facet modeling are based upon set theory, formal concept analysis, and light-weight ontologies, but in many regards, they are implementations of faceted browsing rather than a specification of the basic, underlying structures and interactions. We will demonstrate that category theory allows us to specify faceted objects and study the relationships and interactions within a faceted browsing system. Resulting implementations can then be constructed through a category-theoretic lens using these models, allowing abstract comparison and communication that naturally support interoperability and reuse.

  3. M-theory model-building and proton stability

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J. [CERN, Geneva (Switzerland). Theory Div.; Faraggi, A.E. [Florida Univ., Gainesville, FL (United States). Inst. for Fundamental Theory; Nanopoulos, D.V. [Texas A and M Univ., College Station, TX (United States)]|[Houston Advanced Research Center, The Woodlands, TX (United States). Astroparticle Physics Group]|[Academy of Athens (Greece). Div. of Natural Sciences

    1997-09-01

    The authors study the problem of baryon stability in M theory, starting from realistic four-dimensional string models constructed using the free-fermion formulation of the weakly-coupled heterotic string. Suitable variants of these models manifest an enhanced custodial gauge symmetry that forbids to all orders the appearance of dangerous dimension-five baryon-decay operators. The authors exhibit the underlying geometric (bosonic) interpretation of these models, which have a Z{sub 2} x Z{sub 2} orbifold structure similar, but not identical, to the class of Calabi-Yau threefold compactifications of M and F theory investigated by Voisin and Borcea. A related generalization of their work may provide a solution to the problem of proton stability in M theory.

  4. Reconstructing constructivism: causal models, Bayesian learning mechanisms, and the theory theory.

    Science.gov (United States)

    Gopnik, Alison; Wellman, Henry M

    2012-11-01

    We propose a new version of the "theory theory" grounded in the computational framework of probabilistic causal models and Bayesian learning. Probabilistic models allow a constructivist but rigorous and detailed approach to cognitive development. They also explain the learning of both more specific causal hypotheses and more abstract framework theories. We outline the new theoretical ideas, explain the computational framework in an intuitive and nontechnical way, and review an extensive but relatively recent body of empirical results that supports these ideas. These include new studies of the mechanisms of learning. Children infer causal structure from statistical information, through their own actions on the world and through observations of the actions of others. Studies demonstrate these learning mechanisms in children from 16 months to 4 years old and include research on causal statistical learning, informal experimentation through play, and imitation and informal pedagogy. They also include studies of the variability and progressive character of intuitive theory change, particularly theory of mind. These studies investigate both the physical and the psychological and social domains. We conclude with suggestions for further collaborative projects between developmental and computational cognitive scientists.

  5. Magnetized cosmological models in bimetric theory of gravitation

    Indian Academy of Sciences (India)

    S D Katore; R S Rane

    2006-08-01

    Bianchi type-III magnetized cosmological model when the field of gravitation is governed by either a perfect fluid or cosmic string is investigated in Rosen's [1] bimetric theory of gravitation. To complete determinate solution, the condition, viz., = (), where is a constant, between the metric potentials is used. We have assumed different equations of state for cosmic string [2] for the complete solution of the model. Some physical and geometrical properties of the exhibited model are discussed and studied.

  6. Hydrodynamics Research on Amphibious Vehicle Systems:Modeling Theory

    Institute of Scientific and Technical Information of China (English)

    JU Nai-jun

    2006-01-01

    For completing the hydrodynamics software development and the engineering application research on the amphibious vehicle systems, hydrodynamic modeling theory of the amphibious vehicle systems is elaborated, which includes to build up the dynamic system model of amphibious vehicle motion on water, gun tracking-aiming-firing, bullet hit and armored check-target, gunner operating control, and the simulation computed model of time domain for random sea wave.

  7. Dynamics in Nonlocal Cosmological Models Derived from String Field Theory

    OpenAIRE

    Joukovskaya, Liudmila

    2007-01-01

    A general class of nonlocal cosmological models is considered. A new method for solving nonlocal Friedmann equations is proposed, and solutions of the Friedmann equations with nonlocal operator are presented. The cosmological properties of these solutions are discussed. Especially indicated is $p$-adic cosmological model in which we have obtained nonsingular bouncing solution and string field theory tachyon model in which we have obtained full solution of nonlocal Friedmann equations with $w=...

  8. A Model of Resurgence Based on Behavioral Momentum Theory

    OpenAIRE

    Shahan, Timothy A; Sweeney, Mary M.

    2011-01-01

    Resurgence is the reappearance of an extinguished behavior when an alternative behavior reinforced during extinction is subsequently placed on extinction. Resurgence is of particular interest because it may be a source of relapse to problem behavior following treatments involving alternative reinforcement. In this article we develop a quantitative model of resurgence based on the augmented model of extinction provided by behavioral momentum theory. The model suggests that alternative reinforc...

  9. Population changes: contemporary models and theories.

    Science.gov (United States)

    Sauvy, A

    1981-01-01

    In many developing countries rapid population growth has promoted a renewed interest in the study of the effect of population growth on economic development. This research takes either the macroeconomic viewpoint, where the nation is the framework, or the microeconomic perspective, where the family is the framework. For expository purposes, the macroeconomic viewpoint is assumed, and an example of such an investment is presented. Attention is directed to the following: a simplified model--housing; the lessons learned from experience (primitive populations, Spain in the 17th and 18th centuries, comparing development in Spain and Italy, 19th century Western Europe, and underdeveloped countries); the positive factors of population growth; and the concept of the optimal rate of growth. Housing is the typical investment that an individual makes. Hence, the housing per person (roughly 1/3 of the necessary amount of housing per family) is taken as a unit, and the calculations are made using averages. The conclusion is that growth is expensive. A population decrease might be advantageous, for this decrease would enable the entire population to benefit from past capital accumulation. It is also believed, "a priori," that population growth is more expensive for a developed than for a developing country. This belief may be attributable to the fact that the capital per person tends to be high in the developed countries. Any further increase in the population requires additional capital investments, driving this ratio even higher. Yet, investment is not the only factor inhibiting economic development. The literature describes factors regarding population growth, yet this writer prefers to emphasize 2 other factors that have been the subject of less study: a growing population's ease of adaptation and the human factor--behavior. A growing population adapts better to new conditions than does a stationary or declining population, and contrary to "a priori" belief, a growing

  10. Perturbation theory for string sigma models

    CERN Document Server

    Bianchi, Lorenzo

    2016-01-01

    In this thesis we investigate quantum aspects of the Green-Schwarz superstring in various AdS backgrounds relevant for the AdS/CFT correspondence, providing several examples of perturbative computations in the corresponding integrable sigma-models. We start by reviewing in details the supercoset construction of the superstring action in $AdS_5 \\times S^5$, pointing out the limits of this procedure for $AdS_4$ and $AdS_3$ backgrounds. For the $AdS_4 \\times CP^3$ case we give a thorough derivation of an alternative action, based on the double-dimensional reduction of eleven-dimensional super-membranes. We then consider the expansion about the BMN vacuum and the S-matrix for the scattering of worldsheet excitations in the decompactification limit. To evaluate its elements efficiently we describe a unitarity-based method resulting in a very compact formula yielding the cut-constructible part of any one-loop two-dimensional S-matrix. In the second part of this review we analyze the superstring action on $AdS_4 \\ti...

  11. Lenses on Reading An Introduction to Theories and Models

    CERN Document Server

    Tracey, Diane H

    2012-01-01

    This widely adopted text explores key theories and models that frame reading instruction and research. Readers learn why theory matters in designing and implementing high-quality instruction and research; how to critically evaluate the assumptions and beliefs that guide their own work; and what can be gained by looking at reading through multiple theoretical lenses. For each theoretical model, classroom applications are brought to life with engaging vignettes and teacher reflections. Research applications are discussed and illustrated with descriptions of exemplary studies. New to This Edition

  12. Effective Field Theory and the No-Core Shell Model

    Directory of Open Access Journals (Sweden)

    Stetcua I.

    2010-04-01

    Full Text Available In finite model space suitable for many-body calculations via the no-core shell model (NCSM, I illustrate the direct application of the effective field theory (EFT principles to solving the many-body Schrödinger equation. Two different avenues for fixing the low-energy constants naturally arising in an EFT approach are discussed. I review results for both nuclear and trapped atomic systems, using effective theories formally similar, albeit describing different underlying physics.

  13. Consistent constraints on the Standard Model Effective Field Theory

    CERN Document Server

    Berthier, Laure

    2015-01-01

    We develop the global constraint picture in the (linear) effective field theory generalisation of the Standard Model, incorporating data from detectors that operated at PEP, PETRA, TRISTAN, SpS, Tevatron, SLAC, LEPI and LEP II, as well as low energy precision data. We fit one hundred observables. We develop a theory error metric for this effective field theory, which is required when constraints on parameters at leading order in the power counting are to be pushed to the percent level, or beyond, unless the cut off scale is assumed to be large, $\\Lambda \\gtrsim \\, 3 \\, {\\rm TeV}$. We more consistently incorporate theoretical errors in this work, avoiding this assumption, and as a direct consequence bounds on some leading parameters are relaxed. We show how an $\\rm S,T$ analysis is modified by the theory errors we include as an illustrative example.

  14. Theory of compressive modeling and simulation

    Science.gov (United States)

    Szu, Harold; Cha, Jae; Espinola, Richard L.; Krapels, Keith

    2013-05-01

    Modeling and Simulation (M&S) has been evolving along two general directions: (i) data-rich approach suffering the curse of dimensionality and (ii) equation-rich approach suffering computing power and turnaround time. We suggest a third approach. We call it (iii) compressive M&S (CM&S); because the basic Minimum Free-Helmholtz Energy (MFE) facilitating CM&S can reproduce and generalize Candes, Romberg, Tao & Donoho (CRT&D) Compressive Sensing (CS) paradigm as a linear Lagrange Constraint Neural network (LCNN) algorithm. CM&S based MFE can generalize LCNN to 2nd order as Nonlinear augmented LCNN. For example, during the sunset, we can avoid a reddish bias of sunlight illumination due to a long-range Rayleigh scattering over the horizon. With CM&S we can take instead of day camera, a night vision camera. We decomposed long wave infrared (LWIR) band with filter into 2 vector components (8~10μm and 10~12μm) and used LCNN to find pixel by pixel the map of Emissive-Equivalent Planck Radiation Sources (EPRS). Then, we up-shifted consistently, according to de-mixed sources map, to the sub-micron RGB color image. Moreover, the night vision imaging can also be down-shifted at Passive Millimeter Wave (PMMW) imaging, suffering less blur owing to dusty smokes scattering and enjoying apparent smoothness of surface reflectivity of man-made objects under the Rayleigh resolution. One loses three orders of magnitudes in the spatial Rayleigh resolution; but gains two orders of magnitude in the reflectivity, and gains another two orders in the propagation without obscuring smog . Since CM&S can generate missing data and hard to get dynamic transients, CM&S can reduce unnecessary measurements and their associated cost and computing in the sense of super-saving CS: measuring one & getting one's neighborhood free .

  15. Theories beyond the standard model, one year before the LHC

    Science.gov (United States)

    Dimopoulos, Savas

    2006-04-01

    Next year the Large Hadron Collider at CERN will begin what may well be a new golden era of particle physics. I will discuss three theories that will be tested at the LHC. I will begin with the supersymmetric standard model, proposed with Howard Georgi in 1981. This theory made a precise quantitative prediction, the unification of couplings, that has been experimentally confirmed in 1991 by experiments at CERN and SLAC. This established it as the leading theory for physics beyond the standard model. Its main prediction, the existence of supersymmetric particles, will be tested at the large hadron collider. I will next overview theories with large new dimensions, proposed with Nima Arkani-Hamed and Gia Dvali in 1998. This links the weakness of gravity to the presence of sub-millimeter size dimensions, that are presently searched for in experiments looking for deviations from Newton's law at short distances. In this framework quantum gravity, string theory, and black holes may be experimentally investigated at the large hadron collider. I will end with the recent proposal of split supersymmetry with Nima Arkani-Hamed. This theory is motivated by the possible existence of an enormous number of ground states in the fundamental theory, as suggested by the cosmological constant problem and recent developments in string theory and cosmology. It can be tested at the large hadron collider and, if confirmed, it will lend support to the idea that our universe and its laws are not unique and that there is an enormous variety of universes each with its own distinct physical laws.

  16. Higher-Rank Supersymmetric Models and Topological Field Theory

    CERN Document Server

    Kawai, T; Yang, S K; Kawai, Toshiya; Uchino, Taku; Yang, Sung-Kil

    1993-01-01

    In the first part of this paper we investigate the operator aspect of higher-rank supersymmetric model which is introduced as a Lie theoretic extension of the $N=2$ minimal model with the simplest case $su(2)$ corresponding to the $N=2$ minimal model. In particular we identify the analogs of chirality conditions and chiral ring. In the second part we construct a class of topological conformal field theories starting with this higher-rank supersymmetric model. We show the BRST-exactness of the twisted stress-energy tensor, find out physical observables and discuss how to make their correlation functions. It is emphasized that in the case of $su(2)$ the topological field theory constructed in this paper is distinct from the one obtained by twisting the $N=2$ minimal model through the usual procedure.

  17. Bridging emotion theory and neurobiology through dynamic systems modeling.

    Science.gov (United States)

    Lewis, Marc D

    2005-04-01

    Efforts to bridge emotion theory with neurobiology can be facilitated by dynamic systems (DS) modeling. DS principles stipulate higher-order wholes emerging from lower-order constituents through bidirectional causal processes--offering a common language for psychological and neurobiological models. After identifying some limitations of mainstream emotion theory, I apply DS principles to emotion-cognition relations. I then present a psychological model based on this reconceptualization, identifying trigger, self-amplification, and self-stabilization phases of emotion-appraisal states, leading to consolidating traits. The article goes on to describe neural structures and functions involved in appraisal and emotion, as well as DS mechanisms of integration by which they interact. These mechanisms include nested feedback interactions, global effects of neuromodulation, vertical integration, action-monitoring, and synaptic plasticity, and they are modeled in terms of both functional integration and temporal synchronization. I end by elaborating the psychological model of emotion-appraisal states with reference to neural processes.

  18. A model of PCF in guarded type theory

    DEFF Research Database (Denmark)

    Paviotti, Marco; Møgelberg, Rasmus Ejlers; Birkedal, Lars

    2015-01-01

    Guarded recursion is a form of recursion where recursive calls are guarded by delay modalities. Previous work has shown how guarded recursion is useful for constructing logics for reasoning about programming languages with advanced features, as well as for constructing and reasoning about elements...... of coinductive types. In this paper we investigate how type theory with guarded recursion can be used as a metalanguage for denotational semantics useful both for constructing models and for proving properties of these. We do this by constructing a fairly intensional model of PCF and proving it computationally...... adequate. The model construction is related to Escardo's metric model for PCF, but here everything is carried out entirely in type theory with guarded recursion, including the formulation of the operational semantics, the model construction and the proof of adequacy...

  19. An introduction to queueing theory modeling and analysis in applications

    CERN Document Server

    Bhat, U Narayan

    2015-01-01

    This introductory textbook is designed for a one-semester course on queueing theory that does not require a course on stochastic processes as a prerequisite. By integrating the necessary background on stochastic processes with the analysis of models, the work provides a sound foundational introduction to the modeling and analysis of queueing systems for a wide interdisciplinary audience of students in mathematics, statistics, and applied disciplines such as computer science, operations research, and engineering. This edition includes additional topics in methodology and applications. Key features: • An introductory chapter including a historical account of the growth of queueing theory in more than 100 years. • A modeling-based approach with emphasis on identification of models. • Rigorous treatment of the foundations of basic models commonly used in applications with appropriate references for advanced topics. • Applications in manufacturing and, computer and communication systems. • A chapter on ...

  20. Cosmological Model Based on Gauge Theory of Gravity

    Institute of Scientific and Technical Information of China (English)

    WU Ning

    2005-01-01

    A cosmological model based on gauge theory of gravity is proposed in this paper. Combining cosmological principle and field equation of gravitational gauge field, dynamical equations of the scale factor R(t) of our universe can be obtained. This set of equations has three different solutions. A prediction of the present model is that, if the energy density of the universe is not zero and the universe is expanding, the universe must be space-flat, the total energy density must be the critical density ρc of the universe. For space-flat case, this model gives the same solution as that of the Friedmann model. In other words, though they have different dynamics of gravitational interactions, general relativity and gauge theory of gravity give the same cosmological model.

  1. Structural properties of effective potential model by liquid state theories

    Institute of Scientific and Technical Information of China (English)

    Xiang Yuan-Tao; Andrej Jamnik; Yang Kai-Wei

    2010-01-01

    This paper investigates the structural properties of a model fluid dictated by an effective inter-particle oscillatory potential by grand canonical ensemble Monte Carlo (GCEMC) simulation and classical liquid state theories. The chosen oscillatory potential incorporates basic interaction terms used in modeling of various complex fluids which is composed of mesoscopic particles dispersed in a solvent bath, the studied structural properties include radial distribution function in bulk and inhomogeneous density distribution profile due to influence of several external fields. The GCEMC results are employed to test the validity of two recently proposed theoretical approaches in the field of atomic fluids. One is an Ornstein-Zernike integral equation theory approach; the other is a third order + second order perturbation density functional theory. Satisfactory agreement between the GCEMC simulation and the pure theories fully indicates the ready adaptability of the atomic fluid theories to effective model potentials in complex fluids, and classifies the proposed theoretical approaches as convenient tools for the investigation of complex fluids under the single component macro-fluid approximation.

  2. Twisted gauge theories in 3D Walker-Wang models

    CERN Document Server

    Wang, Zitao

    2016-01-01

    Three dimensional gauge theories with a discrete gauge group can emerge from spin models as a gapped topological phase with fractional point excitations (gauge charge) and loop excitations (gauge flux). It is known that 3D gauge theories can be "twisted", in the sense that the gauge flux loops can have nontrivial braiding statistics among themselves and such twisted gauge theories are realized in models discovered by Dijkgraaf and Witten. A different framework to systematically construct three dimensional topological phases was proposed by Walker and Wang and a series of examples have been studied. Can the Walker Wang construction be used to realize the topological order in twisted gauge theories? This is not immediately clear because the Walker-Wang construction is based on a loop condensation picture while the Dijkgraaf-Witten theory is based on a membrane condensation picture. In this paper, we show that the answer to this question is Yes, by presenting an explicit construction of the Walker Wang models wh...

  3. Theory, modeling and simulation of superconducting qubits

    Energy Technology Data Exchange (ETDEWEB)

    Berman, Gennady P [Los Alamos National Laboratory; Kamenev, Dmitry I [Los Alamos National Laboratory; Chumak, Alexander [INSTIT OF PHYSICS, KIEV; Kinion, Carin [LLNL; Tsifrinovich, Vladimir [POLYTECHNIC INSTIT OF NYU

    2011-01-13

    We analyze the dynamics of a qubit-resonator system coupled with a thermal bath and external electromagnetic fields. Using the evolution equations for the set of Heisenberg operators that describe the whole system, we derive an expression for the resonator field, that includes the resonator-drive, the resonator-bath, and resonator-qubit interactions. The renormalization of the resonator frequency, caused by the qubit-resonator interaction, is accounted for. Using the solutions for the resonator field, we derive the equation that describes the qubit dynamics. The dependence of the qubit evolution during the measurement time on the fidelity of a single-shot measurement is studied. The relation between the fidelity and measurement time is shown explicitly. We proposed a novel adiabatic method for the phase qubit measurement. The method utilizes a low-frequency, quasi-classical resonator inductively coupled to the qubit. The resonator modulates the qubit energy, and the back reaction of the qubit causes a shift in the phase of the resonator. The resonator phase shift can be used to determine the qubit state. We have simulated this measurement taking into the account the energy levels outside the phase qubit manifold. We have shown that, for qubit frequencies in the range of 8-12GHZ, a resonator frequency of 500 MHz and a measurement time of 100 ns, the phase difference between the two qubit states is greater than 0.2 rad. This phase difference exceeds the measurement uncertainty, and can be detected using a classical phase-meter. A fidelity of 0.9999 can be achieved for a relaxation time of 0.5 ms. We also model and simulate a microstrip-SQUID amplifier of frequency about 500 MHz, which could be used to amplify the resonator oscillations in the phase qubit adiabatic measurement. The voltage gain and the amplifier noise temperature are calculated. We simulate the preparation of a generalized Bell state and compute the relaxation times required for achieving high

  4. Theory, modeling and simulation of superconducting qubits

    Energy Technology Data Exchange (ETDEWEB)

    Berman, Gennady P [Los Alamos National Laboratory; Kamenev, Dmitry I [Los Alamos National Laboratory; Chumak, Alexander [INSTIT OF PHYSICS, KIEV; Kinion, Carin [LLNL; Tsifrinovich, Vladimir [POLYTECHNIC INSTIT OF NYU

    2011-01-13

    We analyze the dynamics of a qubit-resonator system coupled with a thermal bath and external electromagnetic fields. Using the evolution equations for the set of Heisenberg operators that describe the whole system, we derive an expression for the resonator field, that includes the resonator-drive, the resonator-bath, and resonator-qubit interactions. The renormalization of the resonator frequency, caused by the qubit-resonator interaction, is accounted for. Using the solutions for the resonator field, we derive the equation that describes the qubit dynamics. The dependence of the qubit evolution during the measurement time on the fidelity of a single-shot measurement is studied. The relation between the fidelity and measurement time is shown explicitly. We proposed a novel adiabatic method for the phase qubit measurement. The method utilizes a low-frequency, quasi-classical resonator inductively coupled to the qubit. The resonator modulates the qubit energy, and the back reaction of the qubit causes a shift in the phase of the resonator. The resonator phase shift can be used to determine the qubit state. We have simulated this measurement taking into the account the energy levels outside the phase qubit manifold. We have shown that, for qubit frequencies in the range of 8-12GHZ, a resonator frequency of 500 MHz and a measurement time of 100 ns, the phase difference between the two qubit states is greater than 0.2 rad. This phase difference exceeds the measurement uncertainty, and can be detected using a classical phase-meter. A fidelity of 0.9999 can be achieved for a relaxation time of 0.5 ms. We also model and simulate a microstrip-SQUID amplifier of frequency about 500 MHz, which could be used to amplify the resonator oscillations in the phase qubit adiabatic measurement. The voltage gain and the amplifier noise temperature are calculated. We simulate the preparation of a generalized Bell state and compute the relaxation times required for achieving high

  5. Traffic Games: Modeling Freeway Traffic with Game Theory

    Science.gov (United States)

    Cortés-Berrueco, Luis E.; Gershenson, Carlos; Stephens, Christopher R.

    2016-01-01

    We apply game theory to a vehicular traffic model to study the effect of driver strategies on traffic flow. The resulting model inherits the realistic dynamics achieved by a two-lane traffic model and aims to incorporate phenomena caused by driver-driver interactions. To achieve this goal, a game-theoretic description of driver interaction was developed. This game-theoretic formalization allows one to model different lane-changing behaviors and to keep track of mobility performance. We simulate the evolution of cooperation, traffic flow, and mobility performance for different modeled behaviors. The analysis of these results indicates a mobility optimization process achieved by drivers’ interactions. PMID:27855176

  6. Traffic Games: Modeling Freeway Traffic with Game Theory.

    Science.gov (United States)

    Cortés-Berrueco, Luis E; Gershenson, Carlos; Stephens, Christopher R

    2016-01-01

    We apply game theory to a vehicular traffic model to study the effect of driver strategies on traffic flow. The resulting model inherits the realistic dynamics achieved by a two-lane traffic model and aims to incorporate phenomena caused by driver-driver interactions. To achieve this goal, a game-theoretic description of driver interaction was developed. This game-theoretic formalization allows one to model different lane-changing behaviors and to keep track of mobility performance. We simulate the evolution of cooperation, traffic flow, and mobility performance for different modeled behaviors. The analysis of these results indicates a mobility optimization process achieved by drivers' interactions.

  7. Thimble regularization at work besides toy models: from Random Matrix Theory to Gauge Theories

    CERN Document Server

    Eruzzi, G

    2015-01-01

    Thimble regularization as a solution to the sign problem has been successfully put at work for a few toy models. Given the non trivial nature of the method (also from the algorithmic point of view) it is compelling to provide evidence that it works for realistic models. A Chiral Random Matrix theory has been studied in detail. The known analytical solution shows that the model is non-trivial as for the sign problem (in particular, phase quenched results can be very far away from the exact solution). This study gave us the chance to address a couple of key issues: how many thimbles contribute to the solution of a realistic problem? Can one devise algorithms which are robust as for staying on the correct manifold? The obvious step forward consists of applications to gauge theories.

  8. Matrix Factorizations for Local F-Theory Models

    CERN Document Server

    Omer, Harun

    2016-01-01

    I use matrix factorizations to describe branes at simple singularities as they appear in elliptic fibrations of local F-theory models. Each node of the corresponding Dynkin diagrams of the ADE-type singularities is associated with one indecomposable matrix factorization which can be deformed into one or more factorizations of lower rank. Branes with internal fluxes arise naturally as bound states of the indecomposable factorizations. Describing branes in such a way avoids the need to resolve singularities and encodes information which is neglected in conventional F-theory treatments. This paper aims to show how branes arising in local F-theory models around simple singularities can be described in this framework.

  9. Integrating social capital theory, social cognitive theory, and the technology acceptance model to explore a behavioral model of telehealth systems.

    Science.gov (United States)

    Tsai, Chung-Hung

    2014-05-07

    Telehealth has become an increasingly applied solution to delivering health care to rural and underserved areas by remote health care professionals. This study integrated social capital theory, social cognitive theory, and the technology acceptance model (TAM) to develop a comprehensive behavioral model for analyzing the relationships among social capital factors (social capital theory), technological factors (TAM), and system self-efficacy (social cognitive theory) in telehealth. The proposed framework was validated with 365 respondents from Nantou County, located in Central Taiwan. Structural equation modeling (SEM) was used to assess the causal relationships that were hypothesized in the proposed model. The finding indicates that elderly residents generally reported positive perceptions toward the telehealth system. Generally, the findings show that social capital factors (social trust, institutional trust, and social participation) significantly positively affect the technological factors (perceived ease of use and perceived usefulness respectively), which influenced usage intention. This study also confirmed that system self-efficacy was the salient antecedent of perceived ease of use. In addition, regarding the samples, the proposed model fitted considerably well. The proposed integrative psychosocial-technological model may serve as a theoretical basis for future research and can also offer empirical foresight to practitioners and researchers in the health departments of governments, hospitals, and rural communities.

  10. Integrating Social Capital Theory, Social Cognitive Theory, and the Technology Acceptance Model to Explore a Behavioral Model of Telehealth Systems

    Directory of Open Access Journals (Sweden)

    Chung-Hung Tsai

    2014-05-01

    Full Text Available Telehealth has become an increasingly applied solution to delivering health care to rural and underserved areas by remote health care professionals. This study integrated social capital theory, social cognitive theory, and the technology acceptance model (TAM to develop a comprehensive behavioral model for analyzing the relationships among social capital factors (social capital theory, technological factors (TAM, and system self-efficacy (social cognitive theory in telehealth. The proposed framework was validated with 365 respondents from Nantou County, located in Central Taiwan. Structural equation modeling (SEM was used to assess the causal relationships that were hypothesized in the proposed model. The finding indicates that elderly residents generally reported positive perceptions toward the telehealth system. Generally, the findings show that social capital factors (social trust, institutional trust, and social participation significantly positively affect the technological factors (perceived ease of use and perceived usefulness respectively, which influenced usage intention. This study also confirmed that system self-efficacy was the salient antecedent of perceived ease of use. In addition, regarding the samples, the proposed model fitted considerably well. The proposed integrative psychosocial-technological model may serve as a theoretical basis for future research and can also offer empirical foresight to practitioners and researchers in the health departments of governments, hospitals, and rural communities.

  11. Excellence in Physics Education Award: Modeling Theory for Physics Instruction

    Science.gov (United States)

    Hestenes, David

    2014-03-01

    All humans create mental models to plan and guide their interactions with the physical world. Science has greatly refined and extended this ability by creating and validating formal scientific models of physical things and processes. Research in physics education has found that mental models created from everyday experience are largely incompatible with scientific models. This suggests that the fundamental problem in learning and understanding science is coordinating mental models with scientific models. Modeling Theory has drawn on resources of cognitive science to work out extensive implications of this suggestion and guide development of an approach to science pedagogy and curriculum design called Modeling Instruction. Modeling Instruction has been widely applied to high school physics and, more recently, to chemistry and biology, with noteworthy results.

  12. Linking Complexity and Sustainability Theories: Implications for Modeling Sustainability Transitions

    Directory of Open Access Journals (Sweden)

    Camaren Peter

    2014-03-01

    Full Text Available In this paper, we deploy a complexity theory as the foundation for integration of different theoretical approaches to sustainability and develop a rationale for a complexity-based framework for modeling transitions to sustainability. We propose a framework based on a comparison of complex systems’ properties that characterize the different theories that deal with transitions to sustainability. We argue that adopting a complexity theory based approach for modeling transitions requires going beyond deterministic frameworks; by adopting a probabilistic, integrative, inclusive and adaptive approach that can support transitions. We also illustrate how this complexity-based modeling framework can be implemented; i.e., how it can be used to select modeling techniques that address particular properties of complex systems that we need to understand in order to model transitions to sustainability. In doing so, we establish a complexity-based approach towards modeling sustainability transitions that caters for the broad range of complex systems’ properties that are required to model transitions to sustainability.

  13. Rational choice theory and Becker's model of random behavior

    Directory of Open Access Journals (Sweden)

    Krstić Miloš

    2015-01-01

    Full Text Available According to rational choice theory, rational consumers tend to maximize utility under a given budget constraints. This will be achieved if they choose a combination of goods that can satisfy their needs and provide the maximum level of utility. Gary Becker, on the other hand, imagines irrational consumers who choose bundle on the budget line. As irrational consumers have an equal probability of choosing any bundle on the budget line, on average, we expect that they will pick the bundle lying at the midpoint of the line. The results of research in which artificial Becker's agents choose among more than two commodities, rational choice theory is small and more than two budget/price situations show that the percentage of agents whose behavior violate. Adding some factors to Becker's model of random behavior, experimenters can minimize these minor violations. Therefore, rational choice theory is unfalsifiable. The results of our research have confirmed this theory. In addition, in the paper we discussed about explanatory value of rational choice theory in specific circumstances (positive substitution effect and we concluded that the explanatory value of rational choice theory was significantly reduced in specific cases.

  14. Pilot evaluation in TENCompetence: a theory-driven model

    NARCIS (Netherlands)

    Schoonenboom, Judith; Sligte, Henk; Moghnieh, Ayman; Specht, Marcus; Glahn, Christian; Stefanov, Krassen

    2007-01-01

    Schoonenboom, J., Sligte, H., Moghnieh, A., Specht, M., Glahn, C., & Stefanov, K. (2007). Pilot evaluation in TENCompetence: a theory-driven model. In T. Navarette, J. Blat & R. Koper (Eds.). Proceedings of the 3rd TENCompetence Open Workshop 'Current Research on IMS Learning Design and Lifelong Com

  15. Anisotropic cosmological models and generalized scalar tensor theory

    Indian Academy of Sciences (India)

    Subenoy Chakraborty; Batul Chandra Santra; Nabajit Chakravarty

    2003-10-01

    In this paper generalized scalar tensor theory has been considered in the background of anisotropic cosmological models, namely, axially symmetric Bianchi-I, Bianchi-III and Kortowski–Sachs space-time. For bulk viscous fluid, both exponential and power-law solutions have been studied and some assumptions among the physical parameters and solutions have been discussed.

  16. Stochastic models in risk theory and management accounting

    NARCIS (Netherlands)

    Brekelmans, R.C.M.

    2000-01-01

    This thesis deals with stochastic models in two fields: risk theory and management accounting. Firstly, two extensions of the classical risk process are analyzed. A method is developed that computes bounds of the probability of ruin for the classical risk rocess extended with a constant interest

  17. Conceptualizations of Creativity: Comparing Theories and Models of Giftedness

    Science.gov (United States)

    Miller, Angie L.

    2012-01-01

    This article reviews seven different theories of giftedness that include creativity as a component, comparing and contrasting how each one conceptualizes creativity as a part of giftedness. The functions of creativity vary across the models, suggesting that while the field of gifted education often cites the importance of creativity, the…

  18. Classical and Quantum Theory of Perturbations in Inflationary Universe Models

    CERN Document Server

    Brandenberger, R H; Mukhanov, V

    1993-01-01

    A brief introduction to the gauge invariant classical and quantum theory of cosmological perturbations is given. The formalism is applied to inflationary Universe models and yields a consistent and unified description of the generation and evolution of fluctuations. A general formula for the amplitude of cosmological perturbations in inflationary cosmology is derived.

  19. Multilevel Higher-Order Item Response Theory Models

    Science.gov (United States)

    Huang, Hung-Yu; Wang, Wen-Chung

    2014-01-01

    In the social sciences, latent traits often have a hierarchical structure, and data can be sampled from multiple levels. Both hierarchical latent traits and multilevel data can occur simultaneously. In this study, we developed a general class of item response theory models to accommodate both hierarchical latent traits and multilevel data. The…

  20. Evaluating hydrological model performance using information theory-based metrics

    Science.gov (United States)

    The accuracy-based model performance metrics not necessarily reflect the qualitative correspondence between simulated and measured streamflow time series. The objective of this work was to use the information theory-based metrics to see whether they can be used as complementary tool for hydrologic m...

  1. Stochastic models in risk theory and management accounting

    NARCIS (Netherlands)

    Brekelmans, R.C.M.

    2000-01-01

    This thesis deals with stochastic models in two fields: risk theory and management accounting. Firstly, two extensions of the classical risk process are analyzed. A method is developed that computes bounds of the probability of ruin for the classical risk rocess extended with a constant interest for

  2. A Proposed Model of Jazz Theory Knowledge Acquisition

    Science.gov (United States)

    Ciorba, Charles R.; Russell, Brian E.

    2014-01-01

    The purpose of this study was to test a hypothesized model that proposes a causal relationship between motivation and academic achievement on the acquisition of jazz theory knowledge. A reliability analysis of the latent variables ranged from 0.92 to 0.94. Confirmatory factor analyses of the motivation (standardized root mean square residual…

  3. [General systems theory, analog models and essential arterial hypertension].

    Science.gov (United States)

    Indovina, I; Bonelli, M

    1991-02-15

    The application of the General System Theory to the fields of biology and particularly of medicine is fraught with many difficulties deriving from the mathematical complexities of application. The authors suggest that these difficulties can be overcome by applying analogical models, thus opening new prospects for the resolution of the manifold problems involved in connection with the study of arterial hypertension.

  4. Conceptualizations of Creativity: Comparing Theories and Models of Giftedness

    Science.gov (United States)

    Miller, Angie L.

    2012-01-01

    This article reviews seven different theories of giftedness that include creativity as a component, comparing and contrasting how each one conceptualizes creativity as a part of giftedness. The functions of creativity vary across the models, suggesting that while the field of gifted education often cites the importance of creativity, the…

  5. A Proposed Model of Jazz Theory Knowledge Acquisition

    Science.gov (United States)

    Ciorba, Charles R.; Russell, Brian E.

    2014-01-01

    The purpose of this study was to test a hypothesized model that proposes a causal relationship between motivation and academic achievement on the acquisition of jazz theory knowledge. A reliability analysis of the latent variables ranged from 0.92 to 0.94. Confirmatory factor analyses of the motivation (standardized root mean square residual…

  6. Application of Health Promotion Theories and Models for Environmental Health

    Science.gov (United States)

    Parker, Edith A.; Baldwin, Grant T.; Israel, Barbara; Salinas, Maria A.

    2004-01-01

    The field of environmental health promotion gained new prominence in recent years as awareness of physical environmental stressors and exposures increased in communities across the country and the world. Although many theories and conceptual models are used routinely to guide health promotion and health education interventions, they are rarely…

  7. Using Conceptual Change Theories to Model Position Concepts in Astronomy

    Science.gov (United States)

    Yang, Chih-Chiang; Hung, Jeng-Fung

    2012-01-01

    The roles of conceptual change and model building in science education are very important and have a profound and wide effect on teaching science. This study examines the change in children's position concepts after instruction, based on different conceptual change theories. Three classes were chosen and divided into three groups, including a…

  8. Stochastic models in risk theory and management accounting

    NARCIS (Netherlands)

    Brekelmans, R.C.M.

    2000-01-01

    This thesis deals with stochastic models in two fields: risk theory and management accounting. Firstly, two extensions of the classical risk process are analyzed. A method is developed that computes bounds of the probability of ruin for the classical risk rocess extended with a constant interest for

  9. Using SAS PROC MCMC for Item Response Theory Models

    Science.gov (United States)

    Ames, Allison J.; Samonte, Kelli

    2015-01-01

    Interest in using Bayesian methods for estimating item response theory models has grown at a remarkable rate in recent years. This attentiveness to Bayesian estimation has also inspired a growth in available software such as WinBUGS, R packages, BMIRT, MPLUS, and SAS PROC MCMC. This article intends to provide an accessible overview of Bayesian…

  10. Cohomological gauge theory, quiver matrix models and Donaldson-Thomas theoryCohomological gauge theory, quiver matrix models and Donaldson-Thomas theory

    NARCIS (Netherlands)

    Cirafici, M.; Sinkovics, A.; Szabo, R.J.

    2009-01-01

    We study the relation between Donaldson–Thomas theory of Calabi–Yau threefolds and a six-dimensional topological Yang–Mills theory. Our main example is the topological U(N) gauge theory on flat space in its Coulomb branch. To evaluate its partition function we use equivariant localization techniques

  11. Theory and modelling of diamond fracture from an atomic perspective.

    Science.gov (United States)

    Brenner, Donald W; Shenderova, Olga A

    2015-03-28

    Discussed in this paper are several theoretical and computational approaches that have been used to better understand the fracture of both single-crystal and polycrystalline diamond at the atomic level. The studies, which include first principles calculations, analytic models and molecular simulations, have been chosen to illustrate the different ways in which this problem has been approached, the conclusions and their reliability that have been reached by these methods, and how these theory and modelling methods can be effectively used together.

  12. On ADE Quiver Models and F-Theory Compactification

    CERN Document Server

    Belhaj, A; Sebbar, A; Sedra, M B

    2006-01-01

    Based on mirror symmetry, we discuss geometric engineering of N=1 ADE quiver models from F-theory compactifications on elliptic K3 surfaces fibered over certain four-dimensional base spaces. The latter are constructed as intersecting 4-cycles according to $ADE$ Dynkin diagrams, thereby mimicking the construction of Calabi-Yau threefolds used in geometric engineering in type II superstring theory. Matter is incorporated by considering D7-branes wrapping these 4-cycles. Using a geometric procedure referred to as folding, we discuss how the corresponding physics can be converted into a scenario with D5-branes wrapping 2-cycles of ALE spaces.

  13. On ADE quiver models and F-theory compactification

    Energy Technology Data Exchange (ETDEWEB)

    Belhaj, A [Department of Mathematics and Statistics, University of Ottawa, 585 King Edward Ave., Ottawa, ON, K1N 6N5 (Canada); Rasmussen, J [Department of Mathematics and Statistics, University of Melbourne, Parkville, Victoria 3010 (Australia); Sebbar, A [Department of Mathematics and Statistics, University of Ottawa, 585 King Edward Ave., Ottawa, ON, K1N 6N5 (Canada); Sedra, M B [Laboratoire de Physique de la Matiere et Rayonnement (LPMR), Morocco Faculte des Sciences, Universite Ibn Tofail, Kenitra, Morocco (Morocco)

    2006-07-21

    Based on mirror symmetry, we discuss geometric engineering of N = 1 ADE quiver models from F-theory compactifications on elliptic K3 surfaces fibred over certain four-dimensional base spaces. The latter are constructed as intersecting 4-cycles according to ADE Dynkin diagrams, thereby mimicking the construction of Calabi-Yau threefolds used in geometric engineering in type II superstring theory. Matter is incorporated by considering D7-branes wrapping these 4-cycles. Using a geometric procedure referred to as folding, we discuss how the corresponding physics can be converted into a scenario with D5-branes wrapping 2-cycles of ALE spaces.

  14. Theory-based Bayesian models of inductive learning and reasoning.

    Science.gov (United States)

    Tenenbaum, Joshua B; Griffiths, Thomas L; Kemp, Charles

    2006-07-01

    Inductive inference allows humans to make powerful generalizations from sparse data when learning about word meanings, unobserved properties, causal relationships, and many other aspects of the world. Traditional accounts of induction emphasize either the power of statistical learning, or the importance of strong constraints from structured domain knowledge, intuitive theories or schemas. We argue that both components are necessary to explain the nature, use and acquisition of human knowledge, and we introduce a theory-based Bayesian framework for modeling inductive learning and reasoning as statistical inferences over structured knowledge representations.

  15. Logic without borders essays on set theory, model theory, philosophical logic and philosophy of mathematics

    CERN Document Server

    Hirvonen, Åsa; Kossak, Roman; Villaveces, Andrés

    2015-01-01

    In recent years, mathematical logic has developed in many directions, the initial unity of its subject matter giving way to a myriad of seemingly unrelated areas. The articles collected here, which range from historical scholarship to recent research in geometric model theory, squarely address this development. These articles also connect to the diverse work of Väänänen, whose ecumenical approach to logic reflects the unity of the discipline.

  16. Cluster density functional theory for lattice models based on the theory of Möbius functions

    Science.gov (United States)

    Lafuente, Luis; Cuesta, José A.

    2005-08-01

    Rosenfeld's fundamental-measure theory for lattice models is given a rigorous formulation in terms of the theory of Möbius functions of partially ordered sets. The free-energy density functional is expressed as an expansion in a finite set of lattice clusters. This set is endowed with a partial order, so that the coefficients of the cluster expansion are connected to its Möbius function. Because of this, it is rigorously proven that a unique such expansion exists for any lattice model. The low-density analysis of the free-energy functional motivates a redefinition of the basic clusters (zero-dimensional cavities) which guarantees a correct zero-density limit of the pair and triplet direct correlation functions. This new definition extends Rosenfeld's theory to lattice models with any kind of short-range interaction (repulsive or attractive, hard or soft, one or multicomponent ...). Finally, a proof is given that these functionals have a consistent dimensional reduction, i.e. the functional for dimension d' can be obtained from that for dimension d (d' < d) if the latter is evaluated at a density profile confined to a d'-dimensional subset.

  17. Cluster density functional theory for lattice models based on the theory of Moebius functions

    Energy Technology Data Exchange (ETDEWEB)

    Lafuente, Luis; Cuesta, Jose A [Grupo Interdisciplinar de Sistemas Complejos (GISC), Departamento de Matematicas, Universidad Carlos III de Madrid, 28911 Leganes, Madrid (Spain)

    2005-08-26

    Rosenfeld's fundamental-measure theory for lattice models is given a rigorous formulation in terms of the theory of Moebius functions of partially ordered sets. The free-energy density functional is expressed as an expansion in a finite set of lattice clusters. This set is endowed with a partial order, so that the coefficients of the cluster expansion are connected to its Moebius function. Because of this, it is rigorously proven that a unique such expansion exists for any lattice model. The low-density analysis of the free-energy functional motivates a redefinition of the basic clusters (zero-dimensional cavities) which guarantees a correct zero-density limit of the pair and triplet direct correlation functions. This new definition extends Rosenfeld's theory to lattice models with any kind of short-range interaction (repulsive or attractive, hard or soft, one or multicomponent ...). Finally, a proof is given that these functionals have a consistent dimensional reduction, i.e. the functional for dimension d' can be obtained from that for dimension d (d' < d) if the latter is evaluated at a density profile confined to a d'-dimensional subset.

  18. Models for probability and statistical inference theory and applications

    CERN Document Server

    Stapleton, James H

    2007-01-01

    This concise, yet thorough, book is enhanced with simulations and graphs to build the intuition of readersModels for Probability and Statistical Inference was written over a five-year period and serves as a comprehensive treatment of the fundamentals of probability and statistical inference. With detailed theoretical coverage found throughout the book, readers acquire the fundamentals needed to advance to more specialized topics, such as sampling, linear models, design of experiments, statistical computing, survival analysis, and bootstrapping.Ideal as a textbook for a two-semester sequence on probability and statistical inference, early chapters provide coverage on probability and include discussions of: discrete models and random variables; discrete distributions including binomial, hypergeometric, geometric, and Poisson; continuous, normal, gamma, and conditional distributions; and limit theory. Since limit theory is usually the most difficult topic for readers to master, the author thoroughly discusses mo...

  19. Modeling size effect in the SMA response: a gradient theory

    Science.gov (United States)

    Tabesh, Majid; Boyd, James G.; Lagoudas, Dimitris C.

    2014-03-01

    Shape memory alloys (SMAs) show size effect in their response. The critical stresses, for instance, for the start of martensite and austenite transformations are reported to increase in some SMA wires for diameters below 100 μm. Simulation of such a behavior cannot be achieved using conventional theories that lack an intrinsic length scale in their constitutive modeling. To enable the size effect, a thermodynamically consistent constitutive model is developed, that in addition to conventional internal variables of martensitic volume fraction and transformation strain, contains the spatial gradient of martensitic volume fraction as an internal variable. The developed theory is simplified for 1D cases and analytical solutions for pure bending of SMA beams are presented. The gradient model captures the size effect in the response of the studied SMA structures.

  20. Fracture and ductile vs. brittle behavior -- Theory, modeling and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Beltz, G.E. [ed.] [Univ. of California, Santa Barbara, CA (United States); Selinger, R.L.B. [ed.] [Catholic Univ., Washington, DC (United States); Kim, K.S. [ed.] [Brown Univ., Providence, RI (United States); Marder, M.P. [ed.] [Univ. of Texas, Austin, TX (United States)

    1999-08-01

    The symposium brought together the many communities that investigate the fundamentals of fracture, with special emphasis on the ductile/brittle transition across a broad spectrum of material classes, fracture at interfaces, and modelling fracture over various length scales. Theoretical techniques discussed ranged from first-principles electronic structure theory to atomistic simulation to mesoscale and continuum theories, along with studies of fractals and scaling in fracture. Experimental and theoretical talks were interspersed throughout all sessions, rather than being segregated. The contributions to this volume generally follow the topical outline upon which the symposium was organized. The first part, dealing with ductile vs. brittle behavior in metals, concerns itself with investigations of high-strength steel, magnesium alloys, ordered intermetallics, and Fe-Cr-Al alloys. The development of analytical methods based on micromechanical models, such as dislocation mechanics and cohesive/contact zone models, are covered in a follow-up section. Nonmetals, including silicon, are considered in Parts 3 and 4. Fractals, chaos, and scaling theories are taken up in Part 5, with a special emphasis on fracture in heterogeneous solids. Modelling based on large populations of dislocations has substantially progressed during the past three years; hence, a section devoted to crystal plasticity and mesoscale dislocation modelling appears next. Finally, the technologically significant area of interfacial fracture, with applications to composites and intergranular fracture, is taken up in Part 7. Separate abstracts were prepared for most of the papers in this book.

  1. Social learning theory and the Health Belief Model.

    Science.gov (United States)

    Rosenstock, I M; Strecher, V J; Becker, M H

    1988-01-01

    The Health Belief Model, social learning theory (recently relabelled social cognitive theory), self-efficacy, and locus of control have all been applied with varying success to problems of explaining, predicting, and influencing behavior. Yet, there is conceptual confusion among researchers and practitioners about the interrelationships of these theories and variables. This article attempts to show how these explanatory factors may be related, and in so doing, posits a revised explanatory model which incorporates self-efficacy into the Health Belief Model. Specifically, self-efficacy is proposed as a separate independent variable along with the traditional health belief variables of perceived susceptibility, severity, benefits, and barriers. Incentive to behave (health motivation) is also a component of the model. Locus of control is not included explicitly because it is believed to be incorporated within other elements of the model. It is predicted that the new formulation will more fully account for health-related behavior than did earlier formulations, and will suggest more effective behavioral interventions than have hitherto been available to health educators.

  2. Matrix models and stochastic growth in Donaldson-Thomas theory

    Energy Technology Data Exchange (ETDEWEB)

    Szabo, Richard J. [Department of Mathematics, Heriot-Watt University, Colin Maclaurin Building, Riccarton, Edinburgh EH14 4AS, United Kingdom and Maxwell Institute for Mathematical Sciences, Edinburgh (United Kingdom); Tierz, Miguel [Grupo de Fisica Matematica, Complexo Interdisciplinar da Universidade de Lisboa, Av. Prof. Gama Pinto, 2, PT-1649-003 Lisboa (Portugal); Departamento de Analisis Matematico, Facultad de Ciencias Matematicas, Universidad Complutense de Madrid, Plaza de Ciencias 3, 28040 Madrid (Spain)

    2012-10-15

    We show that the partition functions which enumerate Donaldson-Thomas invariants of local toric Calabi-Yau threefolds without compact divisors can be expressed in terms of specializations of the Schur measure. We also discuss the relevance of the Hall-Littlewood and Jack measures in the context of BPS state counting and study the partition functions at arbitrary points of the Kaehler moduli space. This rewriting in terms of symmetric functions leads to a unitary one-matrix model representation for Donaldson-Thomas theory. We describe explicitly how this result is related to the unitary matrix model description of Chern-Simons gauge theory. This representation is used to show that the generating functions for Donaldson-Thomas invariants are related to tau-functions of the integrable Toda and Toeplitz lattice hierarchies. The matrix model also leads to an interpretation of Donaldson-Thomas theory in terms of non-intersecting paths in the lock-step model of vicious walkers. We further show that these generating functions can be interpreted as normalization constants of a corner growth/last-passage stochastic model.

  3. Matrix models and stochastic growth in Donaldson-Thomas theory

    Science.gov (United States)

    Szabo, Richard J.; Tierz, Miguel

    2012-10-01

    We show that the partition functions which enumerate Donaldson-Thomas invariants of local toric Calabi-Yau threefolds without compact divisors can be expressed in terms of specializations of the Schur measure. We also discuss the relevance of the Hall-Littlewood and Jack measures in the context of BPS state counting and study the partition functions at arbitrary points of the Kähler moduli space. This rewriting in terms of symmetric functions leads to a unitary one-matrix model representation for Donaldson-Thomas theory. We describe explicitly how this result is related to the unitary matrix model description of Chern-Simons gauge theory. This representation is used to show that the generating functions for Donaldson-Thomas invariants are related to tau-functions of the integrable Toda and Toeplitz lattice hierarchies. The matrix model also leads to an interpretation of Donaldson-Thomas theory in terms of non-intersecting paths in the lock-step model of vicious walkers. We further show that these generating functions can be interpreted as normalization constants of a corner growth/last-passage stochastic model.

  4. Nonequilibrium Dynamical Mean-Field Theory for Bosonic Lattice Models

    Science.gov (United States)

    Strand, Hugo U. R.; Eckstein, Martin; Werner, Philipp

    2015-01-01

    We develop the nonequilibrium extension of bosonic dynamical mean-field theory and a Nambu real-time strong-coupling perturbative impurity solver. In contrast to Gutzwiller mean-field theory and strong-coupling perturbative approaches, nonequilibrium bosonic dynamical mean-field theory captures not only dynamical transitions but also damping and thermalization effects at finite temperature. We apply the formalism to quenches in the Bose-Hubbard model, starting from both the normal and the Bose-condensed phases. Depending on the parameter regime, one observes qualitatively different dynamical properties, such as rapid thermalization, trapping in metastable superfluid or normal states, as well as long-lived or strongly damped amplitude oscillations. We summarize our results in nonequilibrium "phase diagrams" that map out the different dynamical regimes.

  5. Should the model for risk-informed regulation be game theory rather than decision theory?

    Science.gov (United States)

    Bier, Vicki M; Lin, Shi-Woei

    2013-02-01

    deception), to identify optimal regulatory strategies. Therefore, we believe that the types of regulatory interactions analyzed in this article are better modeled using game theory rather than decision theory. In particular, the goals of this article are to review the relevant literature in game theory and regulatory economics (to stimulate interest in this area among risk analysts), and to present illustrative results showing how the application of game theory can provide useful insights into the theory and practice of risk-informed regulation. © 2012 Society for Risk Analysis.

  6. Kitaev Lattice Models as a Hopf Algebra Gauge Theory

    Science.gov (United States)

    Meusburger, Catherine

    2017-07-01

    We prove that Kitaev's lattice model for a finite-dimensional semisimple Hopf algebra H is equivalent to the combinatorial quantisation of Chern-Simons theory for the Drinfeld double D( H). This shows that Kitaev models are a special case of the older and more general combinatorial models. This equivalence is an analogue of the relation between Turaev-Viro and Reshetikhin-Turaev TQFTs and relates them to the quantisation of moduli spaces of flat connections. We show that the topological invariants of the two models, the algebra of operators acting on the protected space of the Kitaev model and the quantum moduli algebra from the combinatorial quantisation formalism, are isomorphic. This is established in a gauge theoretical picture, in which both models appear as Hopf algebra valued lattice gauge theories. We first prove that the triangle operators of a Kitaev model form a module algebra over a Hopf algebra of gauge transformations and that this module algebra is isomorphic to the lattice algebra in the combinatorial formalism. Both algebras can be viewed as the algebra of functions on gauge fields in a Hopf algebra gauge theory. The isomorphism between them induces an algebra isomorphism between their subalgebras of invariants, which are interpreted as gauge invariant functions or observables. It also relates the curvatures in the two models, which are given as holonomies around the faces of the lattice. This yields an isomorphism between the subalgebras obtained by projecting out curvatures, which can be viewed as the algebras of functions on flat gauge fields and are the topological invariants of the two models.

  7. Nonrelativistic factorizable scattering theory of multicomponent Calogero-Sutherland model

    CERN Document Server

    Ahn, C; Nam, S; Ahn, Changrim; Lee, Kong Ju Bock; Nam, Soonkeon

    1995-01-01

    We relate two integrable models in (1+1) dimensions, namely, multicomponent Calogero-Sutherland model with particles and antiparticles interacting via the hyperbolic potential and the nonrelativistic factorizable S-matrix theory with SU(N)-invariance. We find complete solutions of the Yang-Baxter equations without implementing the crossing symmetry, and one of them is identified with the scattering amplitudes derived from the Schr\\"{o}dinger equation of the Calogero-Sutherland model. This particular solution is of interest in that it cannot be obtained as a nonrelativistic limit of any known relativistic solutions of the SU(N)-invariant Yang-Baxter equations.

  8. Massive mu pair production in a vector field theory model

    CERN Document Server

    Halliday, I G

    1976-01-01

    Massive electrodynamics is treated as a model for the production of massive mu pairs in high-energy hadronic collisions. The dominant diagrams in perturbation theory are identified and analyzed. These graphs have an eikonal structure which leads to enormous cancellations in the two-particle inclusive cross section but not in the n-particle production cross sections. Under the assumption that these cancellations are complete, a Drell-Yan structure appears in the inclusive cross section but the particles accompanying the mu pairs have a very different structure compared to the parton model. The pionization region is no longer empty of particles as in single parton models. (10 refs).

  9. Entanglement of Conceptual Entities in Quantum Model Theory (QMod)

    CERN Document Server

    Aerts, Diederik

    2012-01-01

    We have recently elaborated 'Quantum Model Theory' (QMod) to model situations where the quantum effects of contextuality, interference, superposition, entanglement and emergence, appear without the entities giving rise to these situations having necessarily to be of microscopic nature. We have shown that QMod models without introducing linearity for the set of the states. In this paper we prove that QMod, although not using linearity for the state space, provides a method of identification for entangled states and an intuitive explanation for their occurrence. We illustrate this method for entanglement identification with concrete examples.

  10. Matrix models and stochastic growth in Donaldson-Thomas theory

    CERN Document Server

    Szabo, Richard J

    2010-01-01

    We show that the partition functions which enumerate Donaldson-Thomas invariants of local toric Calabi-Yau threefolds without compact divisors can be expressed in terms of specializations of the Schur measure. We also discuss the relevance of the Hall-Littlewood and Jack measures in the context of BPS state counting and study the partition functions at arbitrary points of the Kaehler moduli space. This rewriting in terms of symmetric functions leads to a unitary one-matrix model representation for Donaldson-Thomas theory. We describe explicitly how this result is related to the unitary matrix model description of Chern-Simons gauge theory. This representation is used to show that the generating functions for Donaldson-Thomas invariants are related to tau-functions of the integrable Toda and Toeplitz lattice hierarchies. The matrix model also leads to an interpretation of Donaldson-Thomas theory in terms of non-intersecting paths in the lock-step model of vicious walkers. We further show that these generating ...

  11. Two velocity difference model for a car following theory

    Science.gov (United States)

    Ge, H. X.; Cheng, R. J.; Li, Z. P.

    2008-09-01

    In the light of the optimal velocity model, a two velocity difference model for a car-following theory is put forward considering navigation in modern traffic. To our knowledge, the model is an improvement over the previous ones theoretically, because it considers more aspects in the car-following process than others. Then we investigate the property of the model using linear and nonlinear analyses. The Korteweg-de Vries equation (for short, the KdV equation) near the neutral stability line and the modified Korteweg-de Vries equation (for short, the mKdV equation) around the critical point are derived by applying the reductive perturbation method. The traffic jam could be thus described by the KdV soliton and the kink-anti-kink soliton for the KdV equation and mKdV equation, respectively. Numerical simulations are made to verify the model, and good results are obtained with the new model.

  12. Symmetry Breaking, Unification, and Theories Beyond the Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, Yasunori

    2009-07-31

    A model was constructed in which the supersymmetric fine-tuning problem is solved without extending the Higgs sector at the weak scale. We have demonstrated that the model can avoid all the phenomenological constraints, while avoiding excessive fine-tuning. We have also studied implications of the model on dark matter physics and collider physics. I have proposed in an extremely simple construction for models of gauge mediation. We found that the {mu} problem can be simply and elegantly solved in a class of models where the Higgs fields couple directly to the supersymmetry breaking sector. We proposed a new way of addressing the flavor problem of supersymmetric theories. We have proposed a new framework of constructing theories of grand unification. We constructed a simple and elegant model of dark matter which explains excess flux of electrons/positrons. We constructed a model of dark energy in which evolving quintessence-type dark energy is naturally obtained. We studied if we can find evidence of the multiverse.

  13. Spatially random models, estimation theory, and robot arm dynamics

    Science.gov (United States)

    Rodriguez, G.

    1987-01-01

    Spatially random models provide an alternative to the more traditional deterministic models used to describe robot arm dynamics. These alternative models can be used to establish a relationship between the methodologies of estimation theory and robot dynamics. A new class of algorithms for many of the fundamental robotics problems of inverse and forward dynamics, inverse kinematics, etc. can be developed that use computations typical in estimation theory. The algorithms make extensive use of the difference equations of Kalman filtering and Bryson-Frazier smoothing to conduct spatial recursions. The spatially random models are very easy to describe and are based on the assumption that all of the inertial (D'Alembert) forces in the system are represented by a spatially distributed white-noise model. The models can also be used to generate numerically the composite multibody system inertia matrix. This is done without resorting to the more common methods of deterministic modeling involving Lagrangian dynamics, Newton-Euler equations, etc. These methods make substantial use of human knowledge in derivation and minipulation of equations of motion for complex mechanical systems.

  14. Supersymmetric Theory of Stochastic ABC Model: A Numerical Study

    CERN Document Server

    Ovchinnikov, Igor V; Ensslin, Torsten A; Wang, Kang L

    2016-01-01

    In this paper, we investigate numerically the stochastic ABC model, a toy model in the theory of astrophysical kinematic dynamos, within the recently proposed supersymmetric theory of stochastics (STS). STS characterises stochastic differential equations (SDEs) by the spectrum of the stochastic evolution operator (SEO) on elements of the exterior algebra or differentials forms over the system's phase space, X. STS can thereby classify SDEs as chaotic or non-chaotic by identifying the phenomenon of stochastic chaos with the spontaneously broken topological supersymmetry that all SDEs possess. We demonstrate the following three properties of the SEO, deduced previously analytically and from physical arguments: the SEO spectra for zeroth and top degree forms never break topological supersymmetry, all SDEs possesses pseudo-time-reversal symmetry, and each de Rahm cohomology class provides one supersymmetric eigenstate. Our results also suggests that the SEO spectra for forms of complementary degrees, i.e., k and ...

  15. Synthetic Domain Theory and Models of Linear Abadi & Plotkin Logic

    DEFF Research Database (Denmark)

    Møgelberg, Rasmus Ejlers; Birkedal, Lars; Rosolini, Guiseppe

    2008-01-01

    Plotkin suggested using a polymorphic dual intuitionistic/linear type theory (PILLY) as a metalanguage for parametric polymorphism and recursion. In recent work the first two authors and R.L. Petersen have defined a notion of parametric LAPL-structure, which are models of PILLY, in which one can...... reason using parametricity and, for example, solve a large class of domain equations, as suggested by Plotkin.In this paper, we show how an interpretation of a strict version of Bierman, Pitts and Russo's language Lily into synthetic domain theory presented by Simpson and Rosolini gives rise...... to a parametric LAPL-structure. This adds to the evidence that the notion of LAPL-structure is a general notion, suitable for treating many different parametric models, and it provides formal proofs of consequences of parametricity expected to hold for the interpretation. Finally, we show how these results...

  16. Standard Model in multi-scale theories and observational constraints

    CERN Document Server

    Calcagni, Gianluca; Rodríguez-Fernández, David

    2015-01-01

    We construct and analyze the Standard Model of electroweak and strong interactions in multi-scale spacetimes with (i) weighted derivatives and (ii) $q$-derivatives. Both theories can be formulated in two different frames, called fractional and integer picture. By definition, the fractional picture is where physical predictions should be made. (i) In the theory with weighted derivatives, it is shown that gauge invariance and the requirement of having constant masses in all reference frames make the Standard Model in the integer picture indistinguishable from the ordinary one. Experiments involving only weak and strong forces are insensitive to a change of spacetime dimensionality also in the fractional picture, and only the electromagnetic and gravitational sectors can break the degeneracy. For the simplest multi-scale measures with only one characteristic time, length and energy scale $t_*$, $\\ell_*$ and $E_*$, we compute the Lamb shift in the hydrogen atom and constrain the multi-scale correction to the ordi...

  17. Quantile hydrologic model selection and model structure deficiency assessment: 1. Theory

    NARCIS (Netherlands)

    Pande, S.

    2013-01-01

    A theory for quantile based hydrologic model selection and model structure deficiency assessment is presented. The paper demonstrates that the degree to which a model selection problem is constrained by the model structure (measured by the Lagrange multipliers of the constraints) quantifies

  18. Quantile hydrologic model selection and model structure deficiency assessment: 1. Theory

    NARCIS (Netherlands)

    Pande, S.

    2013-01-01

    A theory for quantile based hydrologic model selection and model structure deficiency assessment is presented. The paper demonstrates that the degree to which a model selection problem is constrained by the model structure (measured by the Lagrange multipliers of the constraints) quantifies structur

  19. Linking Simple Economic Theory Models and the Cointegrated Vector AutoRegressive Model

    DEFF Research Database (Denmark)

    Møller, Niels Framroze

    This paper attempts to clarify the connection between simple economic theory models and the approach of the Cointegrated Vector-Auto-Regressive model (CVAR). By considering (stylized) examples of simple static equilibrium models, it is illustrated in detail, how the theoretical model and its...

  20. Ranking streamflow model performance based on Information theory metrics

    Science.gov (United States)

    Martinez, Gonzalo; Pachepsky, Yakov; Pan, Feng; Wagener, Thorsten; Nicholson, Thomas

    2016-04-01

    The accuracy-based model performance metrics not necessarily reflect the qualitative correspondence between simulated and measured streamflow time series. The objective of this work was to use the information theory-based metrics to see whether they can be used as complementary tool for hydrologic model evaluation and selection. We simulated 10-year streamflow time series in five watersheds located in Texas, North Carolina, Mississippi, and West Virginia. Eight model of different complexity were applied. The information-theory based metrics were obtained after representing the time series as strings of symbols where different symbols corresponded to different quantiles of the probability distribution of streamflow. The symbol alphabet was used. Three metrics were computed for those strings - mean information gain that measures the randomness of the signal, effective measure complexity that characterizes predictability and fluctuation complexity that characterizes the presence of a pattern in the signal. The observed streamflow time series has smaller information content and larger complexity metrics than the precipitation time series. Watersheds served as information filters and and streamflow time series were less random and more complex than the ones of precipitation. This is reflected the fact that the watershed acts as the information filter in the hydrologic conversion process from precipitation to streamflow. The Nash Sutcliffe efficiency metric increased as the complexity of models increased, but in many cases several model had this efficiency values not statistically significant from each other. In such cases, ranking models by the closeness of the information-theory based parameters in simulated and measured streamflow time series can provide an additional criterion for the evaluation of hydrologic model performance.

  1. Building Better Ecological Machines: Complexity Theory and Alternative Economic Models

    Directory of Open Access Journals (Sweden)

    Jess Bier

    2016-12-01

    Full Text Available Computer models of the economy are regularly used to predict economic phenomena and set financial policy. However, the conventional macroeconomic models are currently being reimagined after they failed to foresee the current economic crisis, the outlines of which began to be understood only in 2007-2008. In this article we analyze the most prominent of this reimagining: Agent-Based models (ABMs. ABMs are an influential alternative to standard economic models, and they are one focus of complexity theory, a discipline that is a more open successor to the conventional chaos and fractal modeling of the 1990s. The modelers who create ABMs claim that their models depict markets as ecologies, and that they are more responsive than conventional models that depict markets as machines. We challenge this presentation, arguing instead that recent modeling efforts amount to the creation of models as ecological machines. Our paper aims to contribute to an understanding of the organizing metaphors of macroeconomic models, which we argue is relevant conceptually and politically, e.g., when models are used for regulatory purposes.

  2. A realistic model for quantum theory with a locality property

    Energy Technology Data Exchange (ETDEWEB)

    Eberhard, P.H.

    1987-04-01

    A model reproducing the predictions of relativistic quantum theory to any desired degree of accuracy is described in this paper. It involves quantities that are independent of the observer's knowledge, and therefore can be called real, and which are defined at each point in space, and therefore can be called local in a rudimentary sense. It involves faster-than-light, but not instantaneous, action at distance.

  3. Embankment deformation analyzed by elastoplastic damage model coupling consolidation theory

    Institute of Scientific and Technical Information of China (English)

    Hong SUN; Xihong ZHAO

    2006-01-01

    The deformation of embankment has serious influences on neighboring structure and infrastructure. A trial embankment is reanalyzed by elastoplastic damage model coupling Biot's consolidation theory. With the increase in time of loading, the damage accumulation becomes larger. Under the centre and toe of embankment, damage becomes serious. Under the centre of embankment, vertical damage values are bigger than horizontal ones. Under the toe of embankment, horizontal damage values are bigger than vertical ones.

  4. Regression modeling methods, theory, and computation with SAS

    CERN Document Server

    Panik, Michael

    2009-01-01

    Regression Modeling: Methods, Theory, and Computation with SAS provides an introduction to a diverse assortment of regression techniques using SAS to solve a wide variety of regression problems. The author fully documents the SAS programs and thoroughly explains the output produced by the programs.The text presents the popular ordinary least squares (OLS) approach before introducing many alternative regression methods. It covers nonparametric regression, logistic regression (including Poisson regression), Bayesian regression, robust regression, fuzzy regression, random coefficients regression,

  5. Game Theory Models for Multi-Robot Patrolling of Infrastructures

    Directory of Open Access Journals (Sweden)

    Erik Hernández

    2013-03-01

    Full Text Available This work is focused on the problem of performing multi‐robot patrolling for infrastructure security applications in order to protect a known environment at critical facilities. Thus, given a set of robots and a set of points of interest, the patrolling task consists of constantly visiting these points at irregular time intervals for security purposes. Current existing solutions for these types of applications are predictable and inflexible. Moreover, most of the previous work has tackled the patrolling problem with centralized and deterministic solutions and only few efforts have been made to integrate dynamic methods. Therefore, one of the main contributions of this work is the development of new dynamic and decentralized collaborative approaches in order to solve the aforementioned problem by implementing learning models from Game Theory. The model selected in this work that includes belief‐based and reinforcement models as special cases is called Experience‐Weighted Attraction. The problem has been defined using concepts of Graph Theory to represent the environment in order to work with such Game Theory techniques. Finally, the proposed methods have been evaluated experimentally by using a patrolling simulator. The results obtained have been compared with previous available approaches.

  6. Application of the evolution theory in modelling of innovation diffusion

    Directory of Open Access Journals (Sweden)

    Krstić Milan

    2016-01-01

    Full Text Available The theory of evolution has found numerous analogies and applications in other scientific disciplines apart from biology. In that sense, today the so-called 'memetic-evolution' has been widely accepted. Memes represent a complex adaptable system, where one 'meme' represents an evolutional cultural element, i.e. the smallest unit of information which can be identified and used in order to explain the evolution process. Among others, the field of innovations has proved itself to be a suitable area where the theory of evolution can also be successfully applied. In this work the authors have started from the assumption that it is also possible to apply the theory of evolution in the modelling of the process of innovation diffusion. Based on the conducted theoretical research, the authors conclude that the process of innovation diffusion in the interpretation of a 'meme' is actually the process of imitation of the 'meme' of innovation. Since during the process of their replication certain 'memes' show a bigger success compared to others, that eventually leads to their natural selection. For the survival of innovation 'memes', their manifestations are of key importance in the sense of their longevity, fruitfulness and faithful replicating. The results of the conducted research have categorically confirmed the assumption of the possibility of application of the evolution theory with the innovation diffusion with the help of innovation 'memes', which opens up the perspectives for some new researches on the subject.

  7. Metacommunity speciation models and their implications for diversification theory.

    Science.gov (United States)

    Hubert, Nicolas; Calcagno, Vincent; Etienne, Rampal S; Mouquet, Nicolas

    2015-08-01

    The emergence of new frameworks combining evolutionary and ecological dynamics in communities opens new perspectives on the study of speciation. By acknowledging the relative contribution of local and regional dynamics in shaping the complexity of ecological communities, metacommunity theory sheds a new light on the mechanisms underlying the emergence of species. Three integrative frameworks have been proposed, involving neutral dynamics, niche theory, and life history trade-offs respectively. Here, we review these frameworks of metacommunity theory to emphasise that: (1) studies on speciation and community ecology have converged towards similar general principles by acknowledging the central role of dispersal in metacommunities dynamics, (2) considering the conditions of emergence and maintenance of new species in communities has given rise to new models of speciation embedded in the metacommunity theory, (3) studies of diversification have shifted from relating phylogenetic patterns to landscapes spatial and ecological characteristics towards integrative approaches that explicitly consider speciation in a mechanistic ecological framework. We highlight several challenges, in particular the need for a better integration of the eco-evolutionary consequences of dispersal and the need to increase our understanding on the relative rates of evolutionary and ecological changes in communities.

  8. Transfer effects between moral dilemmas: a causal model theory.

    Science.gov (United States)

    Wiegmann, Alex; Waldmann, Michael R

    2014-04-01

    Evaluations of analogous situations are an important source for our moral intuitions. A puzzling recent set of findings in experiments exploring transfer effects between intuitions about moral dilemmas has demonstrated a striking asymmetry. Transfer often occurred with a specific ordering of moral dilemmas, but not when the sequence was reversed. In this article we present a new theory of transfer between moral intuitions that focuses on two components of moral dilemmas, namely their causal structure and their default evaluations. According to this theory, transfer effects are expected when the causal models underlying the considered dilemmas allow for a mapping of the highlighted aspect of the first scenario onto the causal structure of the second dilemma, and when the default evaluations of the two dilemmas substantially differ. The theory's key predictions for the occurrence and the direction of transfer effects between two moral dilemmas are tested in five experiments with various variants of moral dilemmas from different domains. A sixth experiment tests the predictions of the theory for how the target action in the moral dilemmas is represented.

  9. Models and applications of chaos theory in modern sciences

    CERN Document Server

    Zeraoulia, Elhadj

    2011-01-01

    This book presents a select group of papers that provide a comprehensive view of the models and applications of chaos theory in medicine, biology, ecology, economy, electronics, mechanical, and the human sciences. Covering both the experimental and theoretical aspects of the subject, it examines a range of current topics of interest. It considers the problems arising in the study of discrete and continuous time chaotic dynamical systems modeling the several phenomena in nature and society-highlighting powerful techniques being developed to meet these challenges that stem from the area of nonli

  10. THE NEW CLASSICAL THEORY AND THE REAL BUSINESS CYCLE MODEL

    Directory of Open Access Journals (Sweden)

    Oana Simona HUDEA (CARAMAN

    2014-11-01

    Full Text Available The present paper aims at describing some key elements of the new classical theory-related model, namely the Real Business Cycle, mainly describing the economy from the perspective of a perfectly competitive market, characterised by price, wage and interest rate flexibility. The rendered impulse-response functions, that help us in revealing the capacity of the model variables to return to their steady state under the impact of a structural shock, be it technology or monetary policy oriented, give points to the neutrality of the monetary entity decisions, therefore confirming the well-known classical dichotomy existing between the nominal and the real factors of the economy.

  11. Theory and Circuit Model for Lossy Coaxial Transmission Line

    Energy Technology Data Exchange (ETDEWEB)

    Genoni, T. C.; Anderson, C. N.; Clark, R. E.; Gansz-Torres, J.; Rose, D. V.; Welch, Dale Robert

    2017-04-01

    The theory of signal propagation in lossy coaxial transmission lines is revisited and new approximate analytic formulas for the line impedance and attenuation are derived. The accuracy of these formulas from DC to 100 GHz is demonstrated by comparison to numerical solutions of the exact field equations. Based on this analysis, a new circuit model is described which accurately reproduces the line response over the entire frequency range. Circuit model calculations are in excellent agreement with the numerical and analytic results, and with finite-difference-time-domain simulations which resolve the skindepths of the conducting walls.

  12. Time-dependent Gutzwiller theory for multiband Hubbard models.

    Science.gov (United States)

    Oelsen, E v; Seibold, G; Bünemann, J

    2011-08-12

    Based on the variational Gutzwiller theory, we present a method for the computation of response functions for multiband Hubbard models with general local Coulomb interactions. The improvement over the conventional random-phase approximation is exemplified for an infinite-dimensional two-band Hubbard model where the incorporation of the local multiplet structure leads to a much larger sensitivity of ferromagnetism on the Hund coupling. Our method can be implemented into local-density approximation and Gutzwiller schemes and will therefore be an important tool for the computation of response functions for strongly correlated materials.

  13. SIMP model at NNLO in chiral perturbation theory

    DEFF Research Database (Denmark)

    Hansen, Martin Rasmus Lundquist; Langaeble, K.; Sannino, F.

    2015-01-01

    We investigate the phenomenological viability of a recently proposed class of composite dark matter models where the relic density is determined by 3 to 2 number-changing processes in the dark sector. Here the pions of the strongly interacting field theory constitute the dark matter particles....... By performing a consistent next-to-leading and next-to-next-to-leading order chiral perturbative investigation we demonstrate that the leading order analysis cannot be used to draw conclusions about the viability of the model. We further show that higher order corrections substantially increase the tension...

  14. Thermodynamic Models from Fluctuation Solution Theory Analysis of Molecular Simulations

    DEFF Research Database (Denmark)

    Christensen, Steen; Peters, Günther H.j.; Hansen, Flemming Yssing

    2007-01-01

    Fluctuation solution theory (FST) is employed to analyze results of molecular dynamics (MD) simulations of liquid mixtures. The objective is to generate parameters for macroscopic GE-models, here the modified Margules model. We present a strategy for choosing the number of parameters included......, Mol. Simul. 33 (4–5) (2007) 449–457.]. The new one has advantages for systems with data points at dilute conditions. Prediction of bubble point pressures using parameters from the two objective functions are compared with experimental data for the binary mixtures methyl acetate–n-pentane and methyl...

  15. Renormalized parameters and perturbation theory in dynamical mean-field theory for the Hubbard model

    Science.gov (United States)

    Hewson, A. C.

    2016-11-01

    We calculate the renormalized parameters for the quasiparticles and their interactions for the Hubbard model in the paramagnetic phase as deduced from the low-energy Fermi-liquid fixed point using the results of a numerical renormalization-group calculation (NRG) and dynamical mean-field theory (DMFT). Even in the low-density limit there is significant renormalization of the local quasiparticle interaction U ˜, in agreement with estimates based on the two-particle scattering theory of J. Kanamori [Prog. Theor. Phys. 30, 275 (1963), 10.1143/PTP.30.275]. On the approach to the Mott transition we find a finite ratio for U ˜/D ˜ , where 2 D ˜ is the renormalized bandwidth, which is independent of whether the transition is approached by increasing the on-site interaction U or on increasing the density to half filling. The leading ω2 term in the self-energy and the local dynamical spin and charge susceptibilities are calculated within the renormalized perturbation theory (RPT) and compared with the results calculated directly from the NRG-DMFT. We also suggest, more generally from the DMFT, how an approximate expression for the q ,ω spin susceptibility χ (q ,ω ) can be derived from repeated quasiparticle scattering with a local renormalized scattering vertex.

  16. Spinors, strings, integrable models, and decomposed Yang-Mills theory

    Science.gov (United States)

    Ioannidou, Theodora; Jiang, Ying; Niemi, Antti J.

    2014-07-01

    This paper deals with various interrelations between strings and surfaces in three-dimensional ambient space, two-dimensional integrable models, and two-dimensional and four-dimensional decomposed SU(2) Yang-Mills theories. Initially, a spinor version of the Frenet equation is introduced in order to describe the differential geometry of static three-dimensional stringlike structures. Then its relation to the structure of the su_(2) Lie algebra valued Maurer-Cartan one-form is presented, while by introducing time evolution of the string a Lax pair is obtained, as an integrability condition. In addition, it is shown how the Lax pair of the integrable nonlinear Schrödinger equation becomes embedded into the Lax pair of the time extended spinor Frenet equation, and it is described how a spinor-based projection operator formalism can be used to construct the conserved quantities, in the case of the nonlinear Schrödinger equation. Then the Lax pair structure of the time extended spinor Frenet equation is related to properties of flat connections in a two-dimensional decomposed SU(2) Yang-Mills theory. In addition, the connection between the decomposed Yang-Mills and the Gauß-Codazzi equation that describes surfaces in three-dimensional ambient space is presented. In that context the relation between isothermic surfaces and integrable models is discussed. Finally, the utility of the Cartan approach to differential geometry is considered. In particular, the similarities between the Cartan formalism and the structure of both two-dimensional and four-dimensional decomposed SU(2) Yang-Mills theories are discussed, while the description of two-dimensional integrable models as embedded structures in the four-dimensional decomposed SU(2) Yang-Mills theory are presented.

  17. Correlators in integrable quantum field theory: the scaling RSOS models

    Energy Technology Data Exchange (ETDEWEB)

    Delfino, G. E-mail: aldo@lpthe.jussieu.fr

    2000-09-11

    The study of the scaling limit of two-dimensional models of statistical mechanics within the framework of integrable field theory is illustrated through the example of the RSOS models. Starting from the exact description of regime III in terms of colliding particles, we compute the correlation functions of the thermal, phi (cursive,open) Greek{sub 1,2} and (for some cases) spin operators in the two-particle approximation. The accuracy obtained for the moments of these correlators is analysed by computing the central charge and the scaling dimensions and comparing with the exact results. We further consider the (generally non-integrable) perturbation of the critical points with both the operators phi (cursive,open) Greek{sub 1,3} and phi (cursive,open) Greek{sub 1,2} and locate the branches solved on the lattice within the associated two-dimensional phase diagram. Finally we discuss the fact that the RSOS models, the dilute q-state Potts model at and the O(n) vector model are all described by the same perturbed conformal field theory.

  18. Toward a General Research Process for Using Dubin's Theory Building Model

    Science.gov (United States)

    Holton, Elwood F.; Lowe, Janis S.

    2007-01-01

    Dubin developed a widely used methodology for theory building, which describes the components of the theory building process. Unfortunately, he does not define a research process for implementing his theory building model. This article proposes a seven-step general research process for implementing Dubin's theory building model. An example of a…

  19. Toward a General Research Process for Using Dubin's Theory Building Model

    Science.gov (United States)

    Holton, Elwood F.; Lowe, Janis S.

    2007-01-01

    Dubin developed a widely used methodology for theory building, which describes the components of the theory building process. Unfortunately, he does not define a research process for implementing his theory building model. This article proposes a seven-step general research process for implementing Dubin's theory building model. An example of a…

  20. Reasoning with Conditionals: A Test of Formal Models of Four Theories

    Science.gov (United States)

    Oberauer, Klaus

    2006-01-01

    The four dominant theories of reasoning from conditionals are translated into formal models: The theory of mental models (Johnson-Laird, P. N., & Byrne, R. M. J. (2002). Conditionals: a theory of meaning, pragmatics, and inference. "Psychological Review," 109, 646-678), the suppositional theory (Evans, J. S. B. T., & Over, D. E. (2004). "If."…

  1. Standard Model in multiscale theories and observational constraints

    Science.gov (United States)

    Calcagni, Gianluca; Nardelli, Giuseppe; Rodríguez-Fernández, David

    2016-08-01

    We construct and analyze the Standard Model of electroweak and strong interactions in multiscale spacetimes with (i) weighted derivatives and (ii) q -derivatives. Both theories can be formulated in two different frames, called fractional and integer picture. By definition, the fractional picture is where physical predictions should be made. (i) In the theory with weighted derivatives, it is shown that gauge invariance and the requirement of having constant masses in all reference frames make the Standard Model in the integer picture indistinguishable from the ordinary one. Experiments involving only weak and strong forces are insensitive to a change of spacetime dimensionality also in the fractional picture, and only the electromagnetic and gravitational sectors can break the degeneracy. For the simplest multiscale measures with only one characteristic time, length and energy scale t*, ℓ* and E*, we compute the Lamb shift in the hydrogen atom and constrain the multiscale correction to the ordinary result, getting the absolute upper bound t*28 TeV . Stronger bounds are obtained from the measurement of the fine-structure constant. (ii) In the theory with q -derivatives, considering the muon decay rate and the Lamb shift in light atoms, we obtain the independent absolute upper bounds t*35 MeV . For α0=1 /2 , the Lamb shift alone yields t*450 GeV .

  2. The linear model and hypothesis a general unifying theory

    CERN Document Server

    Seber, George

    2015-01-01

    This book provides a concise and integrated overview of hypothesis testing in four important subject areas, namely linear and nonlinear models, multivariate analysis, and large sample theory. The approach used is a geometrical one based on the concept of projections and their associated idempotent matrices, thus largely avoiding the need to involve matrix ranks. It is shown that all the hypotheses encountered are either linear or asymptotically linear, and that all the underlying models used are either exactly or asymptotically linear normal models. This equivalence can be used, for example, to extend the concept of orthogonality in the analysis of variance to other models, and to show that the asymptotic equivalence of the likelihood ratio, Wald, and Score (Lagrange Multiplier) hypothesis tests generally applies.

  3. Integrating dynamic energy budget (DEB) theory with traditional bioenergetic models.

    Science.gov (United States)

    Nisbet, Roger M; Jusup, Marko; Klanjscek, Tin; Pecquerie, Laure

    2012-03-15

    Dynamic energy budget (DEB) theory offers a systematic, though abstract, way to describe how an organism acquires and uses energy and essential elements for physiological processes, in addition to how physiological performance is influenced by environmental variables such as food density and temperature. A 'standard' DEB model describes the performance (growth, development, reproduction, respiration, etc.) of all life stages of an animal (embryo to adult), and predicts both intraspecific and interspecific variation in physiological rates. This approach contrasts with a long tradition of more phenomenological and parameter-rich bioenergetic models that are used to make predictions from species-specific rate measurements. These less abstract models are widely used in fisheries studies; they are more readily interpretable than DEB models, but lack the generality of DEB models. We review the interconnections between the two approaches and present formulae relating the state variables and fluxes in the standard DEB model to measured bioenergetic rate processes. We illustrate this synthesis for two large fishes: Pacific bluefin tuna (Thunnus orientalis) and Pacific salmon (Oncorhynchus spp.). For each, we have a parameter-sparse, full-life-cycle DEB model that requires adding only a few species-specific features to the standard model. Both models allow powerful integration of knowledge derived from data restricted to certain life stages, processes and environments.

  4. Applications of the Likelihood Theory in Finance: Modelling and Pricing

    CERN Document Server

    Janssen, Arnold

    2012-01-01

    This paper discusses the connection between mathematical finance and statistical modelling which turns out to be more than a formal mathematical correspondence. We like to figure out how common results and notions in statistics and their meaning can be translated to the world of mathematical finance and vice versa. A lot of similarities can be expressed in terms of LeCam's theory for statistical experiments which is the theory of the behaviour of likelihood processes. For positive prices the arbitrage free financial assets fit into filtered experiments. It is shown that they are given by filtered likelihood ratio processes. From the statistical point of view, martingale measures, completeness and pricing formulas are revisited. The pricing formulas for various options are connected with the power functions of tests. For instance the Black-Scholes price of a European option has an interpretation as Bayes risk of a Neyman Pearson test. Under contiguity the convergence of financial experiments and option prices ...

  5. DsixTools: the standard model effective field theory toolkit

    Energy Technology Data Exchange (ETDEWEB)

    Celis, Alejandro [Ludwig-Maximilians-Universitaet Muenchen, Fakultaet fuer Physik, Arnold Sommerfeld Center for Theoretical Physics, Munich (Germany); Fuentes-Martin, Javier; Vicente, Avelino [Universitat de Valencia-CSIC, Instituto de Fisica Corpuscular, Valencia (Spain); Virto, Javier [University of Bern, Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, Bern (Switzerland)

    2017-06-15

    We present DsixTools, a Mathematica package for the handling of the dimension-six standard model effective field theory. Among other features, DsixTools allows the user to perform the full one-loop renormalization group evolution of the Wilson coefficients in the Warsaw basis. This is achieved thanks to the SMEFTrunner module, which implements the full one-loop anomalous dimension matrix previously derived in the literature. In addition, DsixTools also contains modules devoted to the matching to the ΔB = ΔS = 1, 2 and ΔB = ΔC = 1 operators of the Weak Effective Theory at the electroweak scale, and their QCD and QED Renormalization group evolution below the electroweak scale. (orig.)

  6. A model theoretic Baire category theorem for simple theories

    CERN Document Server

    Shami, Ziv

    2009-01-01

    We define the class of $\\tilde\\tau_{low}^f$-sets. This is a class of type-definable sets defined in terms of forking by low formulas. We prove a model theoretic Baire category theorem for $\\tilde\\tau_{low}^f$-sets in a countable simple theory in which the extension property is first-order and show some of its applications. A typical application is the following. Let $T$ be a countable theory with the wnfcp (weak nonfinite cover property) and assume for every non-algebraic $a$ there exists a non-algebraic $a'\\acl(a)$ such that $SU(a')<\\omega$. Then there exists a weakly-minimal formula with parameters.

  7. Visceral obesity and psychosocial stress: a generalised control theory model

    Science.gov (United States)

    Wallace, Rodrick

    2016-07-01

    The linking of control theory and information theory via the Data Rate Theorem and its generalisations allows for construction of necessary conditions statistical models of body mass regulation in the context of interaction with a complex dynamic environment. By focusing on the stress-related induction of central obesity via failure of HPA axis regulation, we explore implications for strategies of prevention and treatment. It rapidly becomes evident that individual-centred biomedical reductionism is an inadequate paradigm. Without mitigation of HPA axis or related dysfunctions arising from social pathologies of power imbalance, economic insecurity, and so on, it is unlikely that permanent changes in visceral obesity for individuals can be maintained without constant therapeutic effort, an expensive - and likely unsustainable - public policy.

  8. D=0 Matrix Model as Conjugate Field Theory

    CERN Document Server

    Ben-Menahem, S

    1993-01-01

    The D=0 matrix model is reformulated as a 2d nonlocal quantum field theory. The interactions occur on the one-dimensional line of hermitian matrix eigenvalues. The field is conjugate to the density of matrix eigenvalues which appears in the Jevicki-Sakita collective field theory. The classical solution of the field equation is either unique or labeled by a discrete index. Such a solution corresponds to the Dyson sea modified by an entropy term. The modification smoothes the sea edges, and interpolates between different eigenvalue bands for multiple-well potentials. Our classical eigenvalue density contains nonplanar effects, and satisfies a local nonlinear Schr\\"odinger equation with similarities to the Marinari-Parisi $D=1$ reformulation. The quantum fluctuations about a classical solution are computable, and the IR and UV divergences are manifestly removed to all orders. The quantum corrections greatly simplify in the double scaling limit, and include both string-perturbative and nonperturbative effects.

  9. A cellular automaton model for evacuation flow using game theory

    Science.gov (United States)

    Guan, Junbiao; Wang, Kaihua; Chen, Fangyue

    2016-11-01

    Game theory serves as a good tool to explore crowd dynamic conflicts during evacuation processes. The purpose of this study is to simulate the complicated interaction behavior among the conflicting pedestrians in an evacuation flow. Two types of pedestrians, namely, defectors and cooperators, are considered, and two important factors including fear index and cost coefficient are taken into account. By combining the snowdrift game theory with a cellular automaton (CA) model, it is shown that the increase of fear index and cost coefficient will lengthen the evacuation time, which is more apparent for large values of cost coefficient. Meanwhile, it is found that the defectors to cooperators ratio could always tend to consistent states despite different values of parameters, largely owing to self-organization effects.

  10. From Landau`s hydrodynamical model to field theory model to field theory models of multiparticle production: a tribute to Peter...

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, F.

    1996-12-31

    We review the assumptions and domain of applicability of Landau`s Hydrodynamical Model. By considering two models of particle production, pair production from strong electric fields and particle production in the linear {sigma} model, we demonstrate that many of Landau`s ideas are verified in explicit field theory calculations.

  11. A study of the logical model of capital market complexity theories

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Analyzes the shortcomings of the classic capital market theories based on EMH and discloses the complexity essence of the capital market. Considering the capital market a complicated, interactive and adaptable dynamic system, with complexity science as the method for researching the operation law of the capital market, this paper constructs a nonlinear logical model to analyze the applied realm, focal point and interrelationship of such theories as dissipative structure theory, chaos theory, fractal theory, synergetics theory, catastrophe theory and scale theory, and summarizes and discusses the achievements and problems of each theory.Based on the research, the paper foretells the developing direction of complexity science in a capital market.

  12. Modelling non-ignorable missing-data mechanisms with item response theory models

    NARCIS (Netherlands)

    Holman, Rebecca; Glas, Cees A.W.

    2005-01-01

    A model-based procedure for assessing the extent to which missing data can be ignored and handling non-ignorable missing data is presented. The procedure is based on item response theory modelling. As an example, the approach is worked out in detail in conjunction with item response data modelled us

  13. The adhesion model as a field theory for cosmological clustering

    Energy Technology Data Exchange (ETDEWEB)

    Rigopoulos, Gerasimos, E-mail: rigopoulos@thphys.uni-heidelberg.de [Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 12, Heidelberg, 69120 Germany (Germany)

    2015-01-01

    The adhesion model has been proposed in the past as an improvement of the Zel'dovich approximation, providing a good description of the formation of the cosmic web. We recast the model as a field theory for cosmological large scale structure, adding a stochastic force to account for power generated from very short, highly non-linear scales that is uncorrelated with the initial power spectrum. The dynamics of this Stochastic Adhesion Model (SAM) is reminiscent of the well known Kardar-Parisi-Zhang equation with the difference that the viscosity and the noise spectrum are time dependent. Choosing the viscosity proportional to the growth factor D restricts the form of noise spectrum through a 1-loop renormalization argument. For this choice, the SAM field theory is renormalizable to one loop. We comment on the suitability of this model for describing the non-linear regime of the CDM power spectrum and its utility as a relatively simple approach to cosmological clustering.

  14. Reduced M(atrix) theory models: ground state solutions

    CERN Document Server

    López, J L

    2015-01-01

    We propose a method to find exact ground state solutions to reduced models of the SU($N$) invariant matrix model arising from the quantization of the 11-dimensional supermembrane action in the light-cone gauge. We illustrate the method by applying it to lower dimensional toy models and for the SU(2) group. This approach could, in principle, be used to find ground state solutions to the complete 9-dimensional model and for any SU($N$) group. The Hamiltonian, the supercharges and the constraints related to the SU($2$) symmetry are built from operators that generate a multicomponent spinorial wave function. The procedure is based on representing the fermionic degrees of freedom by means of Dirac-like gamma matrices, as was already done in the first proposal of supersymmetric (SUSY) quantum cosmology. We exhibit a relation between these finite $N$ matrix theory ground state solutions and SUSY quantum cosmology wave functions giving a possible physical significance of the theory even for finite $N$.

  15. Plane answers to complex questions the theory of linear models

    CERN Document Server

    Christensen, Ronald

    1987-01-01

    This book was written to rigorously illustrate the practical application of the projective approach to linear models. To some, this may seem contradictory. I contend that it is possible to be both rigorous and illustrative and that it is possible to use the projective approach in practical applications. Therefore, unlike many other books on linear models, the use of projections and sub­ spaces does not stop after the general theory. They are used wherever I could figure out how to do it. Solving normal equations and using calculus (outside of maximum likelihood theory) are anathema to me. This is because I do not believe that they contribute to the understanding of linear models. I have similar feelings about the use of side conditions. Such topics are mentioned when appropriate and thenceforward avoided like the plague. On the other side of the coin, I just as strenuously reject teaching linear models with a coordinate free approach. Although Joe Eaton assures me that the issues in complicated problems freq...

  16. Queuing theory accurately models the need for critical care resources.

    Science.gov (United States)

    McManus, Michael L; Long, Michael C; Cooper, Abbot; Litvak, Eugene

    2004-05-01

    Allocation of scarce resources presents an increasing challenge to hospital administrators and health policy makers. Intensive care units can present bottlenecks within busy hospitals, but their expansion is costly and difficult to gauge. Although mathematical tools have been suggested for determining the proper number of intensive care beds necessary to serve a given demand, the performance of such models has not been prospectively evaluated over significant periods. The authors prospectively collected 2 years' admission, discharge, and turn-away data in a busy, urban intensive care unit. Using queuing theory, they then constructed a mathematical model of patient flow, compared predictions from the model to observed performance of the unit, and explored the sensitivity of the model to changes in unit size. The queuing model proved to be very accurate, with predicted admission turn-away rates correlating highly with those actually observed (correlation coefficient = 0.89). The model was useful in predicting both monthly responsiveness to changing demand (mean monthly difference between observed and predicted values, 0.4+/-2.3%; range, 0-13%) and the overall 2-yr turn-away rate for the unit (21%vs. 22%). Both in practice and in simulation, turn-away rates increased exponentially when utilization exceeded 80-85%. Sensitivity analysis using the model revealed rapid and severe degradation of system performance with even the small changes in bed availability that might result from sudden staffing shortages or admission of patients with very long stays. The stochastic nature of patient flow may falsely lead health planners to underestimate resource needs in busy intensive care units. Although the nature of arrivals for intensive care deserves further study, when demand is random, queuing theory provides an accurate means of determining the appropriate supply of beds.

  17. Models for Broad Area Event Identification and Yield Estimation: Multiple Coda Types

    Science.gov (United States)

    2011-09-01

    microearthquakes accompanying hydraulic fracturing in granitic rock, Bull. Seism . Soc. Am., 81, 553-575, 1991. Fisk, M. and S. R. Taylor, (2007...146882, pp. 13. Yang, X., T. Lay, X.-B. Xie, and M. S. Thorne (2007). Geometric spreading of Pn and Sn in a spherical Earth model, Bull. Seism . Soc

  18. Interactions between causal models, theories, and social cognitive development.

    Science.gov (United States)

    Sobel, David M; Buchanan, David W; Butterfield, Jesse; Jenkins, Odest Chadwicke

    2010-01-01

    We propose a model of social cognitive development based not on a single modeling framework or the hypothesis that a single model accounts for children's developing social cognition. Rather, we advocate a Causal Model approach (cf. Waldmann, 1996), in which models of social cognitive development take the same position as theories of social cognitive development, in that they generate novel empirical hypotheses. We describe this approach and present three examples across various aspects of social cognitive development. Our first example focuses on children's understanding of pretense and involves only considering assumptions made by a computational framework. The second example focuses on children's learning from "testimony". It uses a modeling framework based on Markov random fields as a computational description of a set of empirical phenomena, and then tests a prediction of that description. The third example considers infants' generalization of action learned from imitation. Here, we use a modified version of the Rational Model of Categorization to explain children's inferences. Taken together, these examples suggest that research in social cognitive development can be assisted by considering how computational modeling can lead researchers towards testing novel hypotheses.

  19. Adapting Structuration Theory as a Comprehensive Theory for Distance Education: The ASTIDE Model

    Science.gov (United States)

    Aktaruzzaman, Md; Plunkett, Margaret

    2016-01-01

    Distance Education (DE) theorists have argued about the requirement for a theory to be comprehensive in a way that can explicate many of the activities associated with DE. Currently, Transactional Distance Theory (TDT) (Moore, 1993) and the Theory of Instructional Dialogue (IDT) (Caspi & Gorsky, 2006) are the most prominent theories, yet they…

  20. BASIC THEORY AND MATHEMATICAL MODELING OF URBAN RAINSTORM WATER LOGGING

    Institute of Scientific and Technical Information of China (English)

    LI Da-ming; ZHANG Hong-ping; LI Bing-fei; XIE Yi-yang; LI Pei-yan; HAN Su-qin

    2004-01-01

    In this paper, a mathematical model for the urban rainstorm water logging was established on the basis of one- and two-dimensional unsteady flow theory and the technique of non-structural irregular grid division. The continuity equation was discretized with the finite volume method. And the momentum equations were differently simplified and discretized for different cases. A method of "special passage" was proposed to deal with small-scale rivers and open channels. The urban drainage system was simplified and simulated in the model. The method of "open slot" was applied to coordinate the alternate calculation of open channel flow and pressure flow in drainage pipes. The model has been applied in Tianjin City and the verification is quite satisfactory.

  1. Study of a model equation in detonation theory: multidimensional effects

    CERN Document Server

    Faria, Luiz M; Rosales, Rodolfo R

    2015-01-01

    We extend the reactive Burgers equation presented in Kasimov et al. Phys. Rev. Lett., 110 (2013) and Faria et al. SIAM J. Appl. Maths, 74 (2014), to include multidimensional effects. Furthermore, we explain how the model can be rationally justified following the ideas of the asymptotic theory developed in Faria et al. JFM (2015). The proposed model is a forced version of the unsteady small disturbance transonic flow equations. We show that for physically reasonable choices of forcing functions, traveling wave solutions akin to detonation waves exist. It is demonstrated that multidimensional effects play an important role in the stability and dynamics of the traveling waves. Numerical simulations indicate that solutions of the model tend to form multi-dimensional patterns analogous to cells in gaseous detonations.

  2. A queueing theory based model for business continuity in hospitals.

    Science.gov (United States)

    Miniati, R; Cecconi, G; Dori, F; Frosini, F; Iadanza, E; Biffi Gentili, G; Niccolini, F; Gusinu, R

    2013-01-01

    Clinical activities can be seen as results of precise and defined events' succession where every single phase is characterized by a waiting time which includes working duration and possible delay. Technology makes part of this process. For a proper business continuity management, planning the minimum number of devices according to the working load only is not enough. A risk analysis on the whole process should be carried out in order to define which interventions and extra purchase have to be made. Markov models and reliability engineering approaches can be used for evaluating the possible interventions and to protect the whole system from technology failures. The following paper reports a case study on the application of the proposed integrated model, including risk analysis approach and queuing theory model, for defining the proper number of device which are essential to guarantee medical activity and comply the business continuity management requirements in hospitals.

  3. Density Functional Theory and Materials Modeling at Atomistic Length Scales

    Directory of Open Access Journals (Sweden)

    Swapan K. Ghosh

    2002-04-01

    Full Text Available Abstract: We discuss the basic concepts of density functional theory (DFT as applied to materials modeling in the microscopic, mesoscopic and macroscopic length scales. The picture that emerges is that of a single unified framework for the study of both quantum and classical systems. While for quantum DFT, the central equation is a one-particle Schrodinger-like Kohn-Sham equation, the classical DFT consists of Boltzmann type distributions, both corresponding to a system of noninteracting particles in the field of a density-dependent effective potential, the exact functional form of which is unknown. One therefore approximates the exchange-correlation potential for quantum systems and the excess free energy density functional or the direct correlation functions for classical systems. Illustrative applications of quantum DFT to microscopic modeling of molecular interaction and that of classical DFT to a mesoscopic modeling of soft condensed matter systems are highlighted.

  4. Dynamic statistical models of biological cognition: insights from communications theory

    Science.gov (United States)

    Wallace, Rodrick

    2014-10-01

    Maturana's cognitive perspective on the living state, Dretske's insight on how information theory constrains cognition, the Atlan/Cohen cognitive paradigm, and models of intelligence without representation, permit construction of a spectrum of dynamic necessary conditions statistical models of signal transduction, regulation, and metabolism at and across the many scales and levels of organisation of an organism and its context. Nonequilibrium critical phenomena analogous to physical phase transitions, driven by crosstalk, will be ubiquitous, representing not only signal switching, but the recruitment of underlying cognitive modules into tunable dynamic coalitions that address changing patterns of need and opportunity at all scales and levels of organisation. The models proposed here, while certainly providing much conceptual insight, should be most useful in the analysis of empirical data, much as are fitted regression equations.

  5. Structure and asymptotic theory for nonlinear models with GARCH errors

    Directory of Open Access Journals (Sweden)

    Felix Chan

    2015-01-01

    Full Text Available Nonlinear time series models, especially those with regime-switching and/or conditionally heteroskedastic errors, have become increasingly popular in the economics and finance literature. However, much of the research has concentrated on the empirical applications of various models, with little theoretical or statistical analysis associated with the structure of the processes or the associated asymptotic theory. In this paper, we derive sufficient conditions for strict stationarity and ergodicity of three different specifications of the first-order smooth transition autoregressions with heteroskedastic errors. This is essential, among other reasons, to establish the conditions under which the traditional LM linearity tests based on Taylor expansions are valid. We also provide sufficient conditions for consistency and asymptotic normality of the Quasi-Maximum Likelihood Estimator for a general nonlinear conditional mean model with first-order GARCH errors.

  6. Rigid Rotor as a Toy Model for Hodge Theory

    CERN Document Server

    Gupta, Saurabh

    2009-01-01

    We apply the superfield approach to the toy model of a rigid rotor and show the existence of the nilpotent and absolutely anticommuting Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST symmetry transformations, under which, the kinetic term and Lagrangian remain invariant. Furthermore, we also derive the off-shell nilpotent and absolutely anticommuting (anti-) co-BRST symmetry transformations, under which, the gauge-fixing term and Lagrangian remain invariant. The anticommutator of the above nilpotent symmetry transformations leads to the derivation of a bosonic symmetry transformation, under which, the ghost terms and Lagrangian remain invariant. Together, the above transformations (and their corresponding generators) respect an algebra that turns out to be the realization of the algebra obeyed by the de Rham cohomological operators of differential geometry. Thus, our present model is a toy model for the Hodge theory.

  7. Rigid rotor as a toy model for Hodge theory

    Science.gov (United States)

    Gupta, Saurabh; Malik, R. P.

    2010-07-01

    We apply the superfield approach to the toy model of a rigid rotor and show the existence of the nilpotent and absolutely anticommuting Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST symmetry transformations, under which, the kinetic term and the action remain invariant. Furthermore, we also derive the off-shell nilpotent and absolutely anticommuting (anti-) co-BRST symmetry transformations, under which, the gauge-fixing term and the Lagrangian remain invariant. The anticommutator of the above nilpotent symmetry transformations leads to the derivation of a bosonic symmetry transformation, under which, the ghost terms and the action remain invariant. Together, the above transformations (and their corresponding generators) respect an algebra that turns out to be a physical realization of the algebra obeyed by the de Rham cohomological operators of differential geometry. Thus, our present model is a toy model for the Hodge theory.

  8. Real space renormalization group theory of disordered models of glasses.

    Science.gov (United States)

    Angelini, Maria Chiara; Biroli, Giulio

    2017-03-28

    We develop a real space renormalization group analysis of disordered models of glasses, in particular of the spin models at the origin of the random first-order transition theory. We find three fixed points, respectively, associated with the liquid state, with the critical behavior, and with the glass state. The latter two are zero-temperature ones; this provides a natural explanation of the growth of effective activation energy scale and the concomitant huge increase of relaxation time approaching the glass transition. The lower critical dimension depends on the nature of the interacting degrees of freedom and is higher than three for all models. This does not prevent 3D systems from being glassy. Indeed, we find that their renormalization group flow is affected by the fixed points existing in higher dimension and in consequence is nontrivial. Within our theoretical framework, the glass transition results in an avoided phase transition.

  9. Theory, modelling and simulation in origins of life studies.

    Science.gov (United States)

    Coveney, Peter V; Swadling, Jacob B; Wattis, Jonathan A D; Greenwell, H Christopher

    2012-08-21

    Origins of life studies represent an exciting and highly multidisciplinary research field. In this review we focus on the contributions made by theory, modelling and simulation to addressing fundamental issues in the domain and the advances these approaches have helped to make in the field. Theoretical approaches will continue to make a major impact at the "systems chemistry" level based on the analysis of the remarkable properties of nonlinear catalytic chemical reaction networks, which arise due to the auto-catalytic and cross-catalytic nature of so many of the putative processes associated with self-replication and self-reproduction. In this way, we describe inter alia nonlinear kinetic models of RNA replication within a primordial Darwinian soup, the origins of homochirality and homochiral polymerization. We then discuss state-of-the-art computationally-based molecular modelling techniques that are currently being deployed to investigate various scenarios relevant to the origins of life.

  10. Twinlike models for self-dual Maxwell-Higgs theories

    Energy Technology Data Exchange (ETDEWEB)

    Bazeia, D.; Hora, E. da [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Dept. de Fisica; Menezes, R. [Universidade Federal da Paraiba (UFPB), Rio Tinto, PB (Brazil). Dept. de Ciencias Exatas

    2012-07-01

    Full text: We present the development of a coherent first-order theoretical framework that allows for the existence of twinlike models in the context of a generalized self-dual Maxwell-Higgs theories. Here, the generalized model is controlled by two dimensionless functions, h (|{phi}|) and w (|{phi}|) , which are functions of the Higgs field only. Furthermore, these functions are assumed to be positive, in order to avoid problems with the energy of the overall model. In this context, for a given constraint between h (|{phi}|), w (|{phi}|) and the symmetry breaking Higgs potential V (|{phi}|), we found BPS equations by minimizing the generalized total energy. Here, even in the presence of non-trivial choices to h (|{phi}|), w (|{phi}|) and V (|{phi}|), the resulting equations mimic the standard first-order ones. Therefore, given the usual finite-energy boundary conditions, the generalized model engenders the very same topologically non-trivial configurations as the standard Maxwell-Higgs theory. The energy of such configurations is bounded from below, this bound being equal to the magnetic flux, which is quantized according the winding number, as expected. Even in this case, it is important to note that the generalized model is not a parametrization of the usual Maxwell-Higgs one. We study the resulting BPS configurations via the canonical radially symmetric Ansatz, and we found electrically non-charged time-independent vortex solutions which engender the very same magnetic field. In this sense, since this field is related to the topological stability of the usual vortex configurations, we believe the stability of the generalized model can be achieve in the same way. We use a combination of theoretical and numerical techniques to show that different choices to h (|{phi}|) and w (|{phi}|) engender different energy densities, even in the presence of the very same field solutions. In this case, we show that all these densities give the very same total energy. (author)

  11. The Gaussian streaming model and Lagrangian effective field theory

    CERN Document Server

    Vlah, Zvonimir; White, Martin

    2016-01-01

    We update the ingredients of the Gaussian streaming model (GSM) for the redshift-space clustering of biased tracers using the techniques of Lagrangian perturbation theory, effective field theory (EFT) and a generalized Lagrangian bias expansion. After relating the GSM to the cumulant expansion, we present new results for the real-space correlation function, mean pairwise velocity and pairwise velocity dispersion including counter terms from EFT and bias terms through third order in the linear density, its leading derivatives and its shear up to second order. We discuss the connection to the Gaussian peaks formalism. We compare the ingredients of the GSM to a suite of large N-body simulations, and show the performance of the theory on the low order multipoles of the redshift-space correlation function and power spectrum. We highlight the importance of a general biasing scheme, which we find to be as important as higher-order corrections due to non-linear evolution for the halos we consider on the scales of int...

  12. The Gaussian streaming model and convolution Lagrangian effective field theory

    Science.gov (United States)

    Vlah, Zvonimir; Castorina, Emanuele; White, Martin

    2016-12-01

    We update the ingredients of the Gaussian streaming model (GSM) for the redshift-space clustering of biased tracers using the techniques of Lagrangian perturbation theory, effective field theory (EFT) and a generalized Lagrangian bias expansion. After relating the GSM to the cumulant expansion, we present new results for the real-space correlation function, mean pairwise velocity and pairwise velocity dispersion including counter terms from EFT and bias terms through third order in the linear density, its leading derivatives and its shear up to second order. We discuss the connection to the Gaussian peaks formalism. We compare the ingredients of the GSM to a suite of large N-body simulations, and show the performance of the theory on the low order multipoles of the redshift-space correlation function and power spectrum. We highlight the importance of a general biasing scheme, which we find to be as important as higher-order corrections due to non-linear evolution for the halos we consider on the scales of interest to us.

  13. Rigorously testing multialternative decision field theory against random utility models.

    Science.gov (United States)

    Berkowitsch, Nicolas A J; Scheibehenne, Benjamin; Rieskamp, Jörg

    2014-06-01

    Cognitive models of decision making aim to explain the process underlying observed choices. Here, we test a sequential sampling model of decision making, multialternative decision field theory (MDFT; Roe, Busemeyer, & Townsend, 2001), on empirical grounds and compare it against 2 established random utility models of choice: the probit and the logit model. Using a within-subject experimental design, participants in 2 studies repeatedly choose among sets of options (consumer products) described on several attributes. The results of Study 1 showed that all models predicted participants' choices equally well. In Study 2, in which the choice sets were explicitly designed to distinguish the models, MDFT had an advantage in predicting the observed choices. Study 2 further revealed the occurrence of multiple context effects within single participants, indicating an interdependent evaluation of choice options and correlations between different context effects. In sum, the results indicate that sequential sampling models can provide relevant insights into the cognitive process underlying preferential choices and thus can lead to better choice predictions.

  14. Modeling of tethered satellite formations using graph theory

    DEFF Research Database (Denmark)

    Larsen, Martin Birkelund; Smith, Roy S; Blanke, Mogens

    2011-01-01

    satellite formation and proposes a method to deduce the equations of motion for the attitude dynamics of the formation in a compact form. The use of graph theory and Lagrange mechanics together allows a broad class of formations to be described using the same framework. A method is stated for finding...... could form stable formations in space are cumbersome when done at a case to case basis, and a common framework providing a basic model of the dynamics of tethered satellite formations can therefore be advantageous. This paper suggests the use of graph theoretical quantities to describe a tethered...

  15. Quantum of field theory for the electroweak Standard Model

    CERN Document Server

    Kleiss, R

    2008-01-01

    In these notes I present the content of relativistic quantum eld theory, and the way it purports to describe the electroweak Standard Model of particle physics, in the way it most appeals to me. I can claim neither exhaustiveness nor absolute mathematical rigour: after all, the subject is physics, not mathematics. The emphasis will be on physicality and applicability, and therefore I concentrate more on Feynman rules and Feynman diagrams than on hypothesized Lagrangians. The drawback of this is, unavoidably, that symmetry considerations retreat somewhat into the background leaving the limelight to diagrammatic results. This is all right: for I do not at present believe that symmetry rules the world.

  16. Stochastical modeling for Viral Disease: Statistical Mechanics and Network Theory

    Science.gov (United States)

    Zhou, Hao; Deem, Michael

    2007-04-01

    Theoretical methods of statistical mechanics are developed and applied to study the immunological response against viral disease, such as dengue. We use this theory to show how the immune response to four different dengue serotypes may be sculpted. It is the ability of avian influenza, to change and to mix, that has given rise to the fear of a new human flu pandemic. Here we propose to utilize a scale free network based stochastic model to investigate the mitigation strategies and analyze the risk.

  17. Psychodynamic theory and pastoral theology: an integrated model.

    Science.gov (United States)

    Garanzini, M J

    The article proposes that a pastoral concern for gay and lesbian individuals must be sensitive to the psychological and social dynamics involved in their attachments, separations, and losses. Drawing on object relations theory and insights from self-psychology, a model is proposed whereby counselor and counselee can examine the cycle of attachment, separation, loss and reattachment that characterizes all important relationships. The suggestion is made that this cycle is applicable to the development and reformulation of life-giving myths and ways of being in the world. Finally, an analysis of the role of early narcissistic wounds and the healing process in therapy is presented.

  18. Theory and Modeling of High-Power Gyrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Nusinovich, Gregory Semeon [Univ. of Maryland, College Park, MD (United States)

    2016-04-29

    This report summarized results of the work performed at the Institute for Research in Electronics and Applied Physics of the University of Maryland (College Park, MD) in the framework of the DOE Grant “Theory and Modeling of High-Power Gyrotrons”. The report covers the work performed in 2011-2014. The research work was performed in three directions: - possibilities of stable gyrotron operation in very high-order modes offering the output power exceeding 1 MW level in long-pulse/continuous-wave regimes, - effect of small imperfections in gyrotron fabrication and alignment on the gyrotron efficiency and operation, - some issues in physics of beam-wave interaction in gyrotrons.

  19. Mean-field theory and self-consistent dynamo modeling

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizawa, Akira; Yokoi, Nobumitsu [Tokyo Univ. (Japan). Inst. of Industrial Science; Itoh, Sanae-I [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics; Itoh, Kimitaka [National Inst. for Fusion Science, Toki, Gifu (Japan)

    2001-12-01

    Mean-field theory of dynamo is discussed with emphasis on the statistical formulation of turbulence effects on the magnetohydrodynamic equations and the construction of a self-consistent dynamo model. The dynamo mechanism is sought in the combination of the turbulent residual-helicity and cross-helicity effects. On the basis of this mechanism, discussions are made on the generation of planetary magnetic fields such as geomagnetic field and sunspots and on the occurrence of flow by magnetic fields in planetary and fusion phenomena. (author)

  20. Molecular Thermodynamic Modeling of Fluctuation Solution Theory Properties

    DEFF Research Database (Denmark)

    O’Connell, John P.; Abildskov, Jens

    2013-01-01

    Fluctuation Solution Theory provides relationships between integrals of the molecular pair total and direct correlation functions and the pressure derivative of solution density, partial molar volumes, and composition derivatives of activity coefficients. For dense fluids, the integrals follow...... for densities and gas solubilities, including ionic liquids and complex mixtures such as coal liquids. The approach is especially useful in systems with strong nonidealities. This chapter describes successful application of such modeling to a wide variety of systems treated over several decades and suggests how...

  1. The Five-Factor Model and Self-Determination Theory

    DEFF Research Database (Denmark)

    Olesen, Martin Hammershøj; Thomsen, Dorthe Kirkegaard; Schnieber, Anette

    This study investigates conceptual overlap vs. distinction between individual differences in personality traits, i.e. the Five-Factor Model; and Self-determination Theory, i.e. general causality orientations. Twelve-hundred-and-eighty-seven freshmen (mean age 21.71; 64% women) completed electronic...... questionnaires of personality traits (NEO-FFI) and causality orientations (GCOS). To test whether covariance between traits and orientations could be attributed to shared or separate latent variables we conducted joint factor analyses. Results reveal that the Autonomy orientation can be distinguished from...

  2. Corvid re-caching without 'theory of mind': a model.

    Directory of Open Access Journals (Sweden)

    Elske van der Vaart

    Full Text Available Scrub jays are thought to use many tactics to protect their caches. For instance, they predominantly bury food far away from conspecifics, and if they must cache while being watched, they often re-cache their worms later, once they are in private. Two explanations have been offered for such observations, and they are intensely debated. First, the birds may reason about their competitors' mental states, with a 'theory of mind'; alternatively, they may apply behavioral rules learned in daily life. Although this second hypothesis is cognitively simpler, it does seem to require a different, ad-hoc behavioral rule for every caching and re-caching pattern exhibited by the birds. Our new theory avoids this drawback by explaining a large variety of patterns as side-effects of stress and the resulting memory errors. Inspired by experimental data, we assume that re-caching is not motivated by a deliberate effort to safeguard specific caches from theft, but by a general desire to cache more. This desire is brought on by stress, which is determined by the presence and dominance of onlookers, and by unsuccessful recovery attempts. We study this theory in two experiments similar to those done with real birds with a kind of 'virtual bird', whose behavior depends on a set of basic assumptions about corvid cognition, and a well-established model of human memory. Our results show that the 'virtual bird' acts as the real birds did; its re-caching reflects whether it has been watched, how dominant its onlooker was, and how close to that onlooker it has cached. This happens even though it cannot attribute mental states, and it has only a single behavioral rule assumed to be previously learned. Thus, our simulations indicate that corvid re-caching can be explained without sophisticated social cognition. Given our specific predictions, our theory can easily be tested empirically.

  3. Reconsideration of r/K Selection Theory Using Stochastic Control Theory and Nonlinear Structured Population Models.

    Directory of Open Access Journals (Sweden)

    Ryo Oizumi

    Full Text Available Despite the fact that density effects and individual differences in life history are considered to be important for evolution, these factors lead to several difficulties in understanding the evolution of life history, especially when population sizes reach the carrying capacity. r/K selection theory explains what types of life strategies evolve in the presence of density effects and individual differences. However, the relationship between the life schedules of individuals and population size is still unclear, even if the theory can classify life strategies appropriately. To address this issue, we propose a few equations on adaptive life strategies in r/K selection where density effects are absent or present. The equations detail not only the adaptive life history but also the population dynamics. Furthermore, the equations can incorporate temporal individual differences, which are referred to as internal stochasticity. Our framework reveals that maximizing density effects is an evolutionarily stable strategy related to the carrying capacity. A significant consequence of our analysis is that adaptive strategies in both selections maximize an identical function, providing both population growth rate and carrying capacity. We apply our method to an optimal foraging problem in a semelparous species model and demonstrate that the adaptive strategy yields a lower intrinsic growth rate as well as a lower basic reproductive number than those obtained with other strategies. This study proposes that the diversity of life strategies arises due to the effects of density and internal stochasticity.

  4. The Interface Between Theory and Data in Structural Equation Models

    Science.gov (United States)

    Grace, James B.; Bollen, Kenneth A.

    2006-01-01

    Structural equation modeling (SEM) holds the promise of providing natural scientists the capacity to evaluate complex multivariate hypotheses about ecological systems. Building on its predecessors, path analysis and factor analysis, SEM allows for the incorporation of both observed and unobserved (latent) variables into theoretically based probabilistic models. In this paper we discuss the interface between theory and data in SEM and the use of an additional variable type, the composite, for representing general concepts. In simple terms, composite variables specify the influences of collections of other variables and can be helpful in modeling general relationships of the sort commonly of interest to ecologists. While long recognized as a potentially important element of SEM, composite variables have received very limited use, in part because of a lack of theoretical consideration, but also because of difficulties that arise in parameter estimation when using conventional solution procedures. In this paper we present a framework for discussing composites and demonstrate how the use of partially reduced form models can help to overcome some of the parameter estimation and evaluation problems associated with models containing composites. Diagnostic procedures for evaluating the most appropriate and effective use of composites are illustrated with an example from the ecological literature. It is argued that an ability to incorporate composite variables into structural equation models may be particularly valuable in the study of natural systems, where concepts are frequently multifaceted and the influences of suites of variables are often of interest.

  5. Fuzzy structure theory modeling of sound-insulation layers in complex vibroacoustic uncertain systems: theory and experimental validation.

    Science.gov (United States)

    Fernandez, Charles; Soize, Christian; Gagliardini, Laurent

    2009-01-01

    The fuzzy structure theory was introduced 20 years ago in order to model the effects of complex subsystems imprecisely known on a master structure. This theory was only aimed at structural dynamics. In this paper, an extension of that theory is proposed in developing an elastoacoustic element useful to model sound-insulation layers for computational vibroacoustics of complex systems. The simplified model constructed enhances computation time and memory allocation because the number of physical and generalized degrees of freedom in the computational vibroacoustic model is not increased. However, these simplifications introduce model uncertainties. In order to take into account these uncertainties, the nonparametric probabilistic approach recently introduced is used. A robust simplified model for sound-insulation layers is then obtained. This model is controlled by a small number of physical and dispersion parameters. First, the extension of the fuzzy structure theory to elastoacoustic element is presented. Second, the computational vibroacoustic model including such an elastoacoustic element to model sound-insulation layer is given. Then, a design methodology to identify the model parameters with experiments is proposed and is experimentally validated. Finally, the theory is applied to an uncertain vibroacoustic system.

  6. Pluralistic and stochastic gene regulation: examples, models and consistent theory.

    Science.gov (United States)

    Salas, Elisa N; Shu, Jiang; Cserhati, Matyas F; Weeks, Donald P; Ladunga, Istvan

    2016-06-01

    We present a theory of pluralistic and stochastic gene regulation. To bridge the gap between empirical studies and mathematical models, we integrate pre-existing observations with our meta-analyses of the ENCODE ChIP-Seq experiments. Earlier evidence includes fluctuations in levels, location, activity, and binding of transcription factors, variable DNA motifs, and bursts in gene expression. Stochastic regulation is also indicated by frequently subdued effects of knockout mutants of regulators, their evolutionary losses/gains and massive rewiring of regulatory sites. We report wide-spread pluralistic regulation in ≈800 000 tightly co-expressed pairs of diverse human genes. Typically, half of ≈50 observed regulators bind to both genes reproducibly, twice more than in independently expressed gene pairs. We also examine the largest set of co-expressed genes, which code for cytoplasmic ribosomal proteins. Numerous regulatory complexes are highly significant enriched in ribosomal genes compared to highly expressed non-ribosomal genes. We could not find any DNA-associated, strict sense master regulator. Despite major fluctuations in transcription factor binding, our machine learning model accurately predicted transcript levels using binding sites of 20+ regulators. Our pluralistic and stochastic theory is consistent with partially random binding patterns, redundancy, stochastic regulator binding, burst-like expression, degeneracy of binding motifs and massive regulatory rewiring during evolution.

  7. Modeling Adversaries in Counterterrorism Decisions Using Prospect Theory.

    Science.gov (United States)

    Merrick, Jason R W; Leclerc, Philip

    2016-04-01

    Counterterrorism decisions have been an intense area of research in recent years. Both decision analysis and game theory have been used to model such decisions, and more recently approaches have been developed that combine the techniques of the two disciplines. However, each of these approaches assumes that the attacker is maximizing its utility. Experimental research shows that human beings do not make decisions by maximizing expected utility without aid, but instead deviate in specific ways such as loss aversion or likelihood insensitivity. In this article, we modify existing methods for counterterrorism decisions. We keep expected utility as the defender's paradigm to seek for the rational decision, but we use prospect theory to solve for the attacker's decision to descriptively model the attacker's loss aversion and likelihood insensitivity. We study the effects of this approach in a critical decision, whether to screen containers entering the United States for radioactive materials. We find that the defender's optimal decision is sensitive to the attacker's levels of loss aversion and likelihood insensitivity, meaning that understanding such descriptive decision effects is important in making such decisions.

  8. Theory and Modeling for the Magnetospheric Multiscale Mission

    Science.gov (United States)

    Hesse, M.; Aunai, N.; Birn, J.; Cassak, P.; Denton, R. E.; Drake, J. F.; Gombosi, T.; Hoshino, M.; Matthaeus, W.; Sibeck, D.; Zenitani, S.

    2016-03-01

    The Magnetospheric Multiscale (MMS) mission will provide measurement capabilities, which will exceed those of earlier and even contemporary missions by orders of magnitude. MMS will, for the first time, be able to measure directly and with sufficient resolution key features of the magnetic reconnection process, down to the critical electron scales, which need to be resolved to understand how reconnection works. Owing to the complexity and extremely high spatial resolution required, no prior measurements exist, which could be employed to guide the definition of measurement requirements, and consequently set essential parameters for mission planning and execution. Insight into expected details of the reconnection process could hence only been obtained from theory and modern kinetic modeling. This situation was recognized early on by MMS leadership, which supported the formation of a fully integrated Theory and Modeling Team (TMT). The TMT participated in all aspects of mission planning, from the proposal stage to individual aspects of instrument performance characteristics. It provided and continues to provide to the mission the latest insights regarding the kinetic physics of magnetic reconnection, as well as associated particle acceleration and turbulence, assuring that, to the best of modern knowledge, the mission is prepared to resolve the inner workings of the magnetic reconnection process. The present paper provides a summary of key recent results or reconnection research by TMT members.

  9. A theory and a computational model of spatial reasoning with preferred mental models.

    Science.gov (United States)

    Ragni, Marco; Knauff, Markus

    2013-07-01

    Inferences about spatial arrangements and relations like "The Porsche is parked to the left of the Dodge and the Ferrari is parked to the right of the Dodge, thus, the Porsche is parked to the left of the Ferrari," are ubiquitous. However, spatial descriptions are often interpretable in many different ways and compatible with several alternative mental models. This article suggests that individuals tackle such indeterminate multiple-model problems by constructing a single, simple, and typical mental model but neglect other possible models. The model that first comes to reasoners' minds is the preferred mental model. It helps save cognitive resources but also leads to reasoning errors and illusory inferences. The article presents a preferred model theory and an instantiation of this theory in the form of a computational model, preferred inferences in reasoning with spatial mental models (PRISM). PRISM can be used to simulate and explain how preferred models are constructed, inspected, and varied in a spatial array that functions as if it were a spatial working memory. A spatial focus inserts tokens into the array, inspects the array to find new spatial relations, and relocates tokens in the array to generate alternative models of the problem description, if necessary. The article also introduces a general measure of difficulty based on the number of necessary focus operations (rather than the number of models). A comparison with results from psychological experiments shows that the theory can explain preferences, errors, and the difficulty of spatial reasoning problems.

  10. Matrix models, noncommutative gauge theory and emergent gravity

    Energy Technology Data Exchange (ETDEWEB)

    Steinacker, Harold [Fakultaet fuer Physik, Universitaet Wien (Austria)

    2009-07-01

    Matrix Models of Yang-Mills type are studied with focus on the effective geometry. It is shown that SU(n) gauge fields and matter on general 4-dimensional noncommutative branes couple to an effective metric, leading to emergent gravity. The effective metric is reminiscent of the open string metric, and depends on the dynamical Poisson structure. Covariant equations of motion are derived, which are protected from quantum corrections due to an underlying Noether theorem. The quantization is discussed qualitatively, which singles out the IKKT model as a candidate for a quantum theory of gravity coupled to matter. UV/IR mixing plays a central role. A mechanism for avoiding the cosmological constant problem is exhibited.

  11. HRM Model in Tourism, Based on Dialectical Systems Theory

    Directory of Open Access Journals (Sweden)

    Simona Šarotar Žižek

    2015-12-01

    Full Text Available A human resources management (HRM model integrating trends in HRM with trends in tourism into a dialectical system by the Dialectical Systems Theory (DST. HRM strategy, integrated within the tourism organization’s (to’s strategy is implemented through functional strategies helping their users to achieve a requisitely holistic (rh HRM strategy replacing the prevailing one-sided ones. to’s strategy covers: employees (1 planning, (2 acquisition and selection, (3 development and training, (4 diversity management, (5 teamwork and creativity, (6 motivation and rewarding, (7 stress reduction and health, (8 relationships, (9 personal holism, (10 well-being, (11 work and results assessment; etc. Everyone matters; their synergy is crucial. An innovated HRM model for TOS, which applies employees’, organizations’ rh and integrates new knowledge about HRM. HRM belongs to central managers’ tools. Their HRM must be adapted for TOS, where employees are crucial.

  12. Mean-field theory of a recurrent epidemiological model.

    Science.gov (United States)

    Nagy, Viktor

    2009-06-01

    Our purpose is to provide a mean-field theory for the discrete time-step susceptible-infected-recovered-susceptible (SIRS) model on uncorrelated networks with arbitrary degree distributions. The effect of network structure, time delays, and infection rate on the stability of oscillating and fixed point solutions is examined through analysis of discrete time mean-field equations. Consideration of two scenarios for disease contagion demonstrates that the manner in which contagion is transmitted from an infected individual to a contacted susceptible individual is of primary importance. In particular, the manner of contagion transmission determines how the degree distribution affects model behavior. We find excellent agreement between our theoretical results and numerical simulations on networks with large average connectivity.

  13. Building SO(10) models from F-theory

    CERN Document Server

    Antoniadis, I

    2012-01-01

    We revisit local F-theory SO(10) and SU(5) GUTs and analyze their properties within the framework of the maximal underlying E_8 symmetry in the elliptic fibration. We consider the symmetry enhancements along the intersections of seven-branes with the GUT surface and study in detail the embedding of the abelian factors undergoing monodromies in the covering gauge groups. We combine flux data from the successive breaking of SO(10) to SU(5) gauge symmetry and subsequently to the Standard Model one, and further constrain the parameters determining the models' particle spectra. In order to eliminate dangerous baryon number violating operators we propose ways to construct matter parity like symmetries from intrinsic geometric origin. We study implementations of the resulting constrained scenario in specific examples obtained for a variety of monodromies.

  14. Building SO(10) models from F-theory

    Science.gov (United States)

    Antoniadis, I.; Leontaris, G. K.

    2012-08-01

    We revisit local F-theory SO(10) and SU(5) GUTs and analyze their properties within the framework of the maximal underlying E 8 symmetry in the elliptic fibration. We consider the symmetry enhancements along the intersections of seven-branes with the GUT surface and study in detail the embedding of the abelian factors undergoing monodromies in the covering gauge groups. We combine flux data from the successive breaking of SO(10) to SU(5) gauge symmetry and subsequently to the Standard Model one, and further constrain the parameters determining the models' particle spectra. In order to eliminate dangerous baryon number violating operators we propose ways to construct matter parity like symmetries from intrinsic geometric origin. We study implementations of the resulting constrained scenario in specific examples obtained for a variety of monodromies.

  15. A Quantitative Theory Model of a Photobleaching Mechanism

    Institute of Scientific and Technical Information of China (English)

    陈同生; 曾绍群; 周炜; 骆清铭

    2003-01-01

    A photobleaching model:D-P(dye-photon interaction)and D-O(Dye-oxygen oxidative reaction)photobleaching theory,is proposed.The quantitative power dependences of photobleaching rates with both one-and two-photon excitations(1 PE and TPE)are obtained.This photobleaching model can be used to elucidate our and other experimental results commendably.Experimental studies of the photobleaching rates for rhodamine B with TPE under unsaturation conditions reveals that the power dependences of photobleaching rates increase with the increasing dye concentration,and that the photobleaching rate of a single molecule increases in the second power of the excitation intensity,which is different from the high-order(> 3)nonlinear dependence of ensemble molecules.

  16. Dynamical 3-Space Gravity Theory: Effects on Polytropic Solar Models

    Directory of Open Access Journals (Sweden)

    Cahill R. T.

    2011-01-01

    Full Text Available Numerous experiments and observations have confirmed the existence of a dynamical 3-space, detectable directly by light-speed anisotropy experiments, and indirectly by means of novel gravitational effects, such as bore hole g-anomalies, predictable black hole masses, flat spiral-galaxy rotation curves, and the expansion of the universe, all without dark matter and dark energy. The dynamics for this 3-space follows from a unique generalisation of Newtonian gravity, once that is cast into a velocity formalism. This new theory of gravity is applied to the solar model of the sun to compute new density, pressure and temperature profiles, using polytrope modelling of the equation of state for the matter. These results should be applied to a re-analysis of solar neutrino production, and to stellar evolution in general.

  17. Dynamical 3-Space Gravity Theory: Effects on Polytropic Solar Models

    Directory of Open Access Journals (Sweden)

    May R. D.

    2011-01-01

    Full Text Available Numerous experiments and observations have confirmed the existence of a dynamical 3-space, detectable directly by light-speed anisotropy experiments, and indirectly by means of novel gravitational effects, such as bore hole g anomalies, predictable black hole masses, flat spiral-galaxy rotation curves, and the expansion of the universe, all without dark matter and dark energy. The dynamics for this 3-space follows from a unique generalisation of Newtonian gravity, once that is cast into a velocity formalism. This new theory of gravity is applied to the solar model of the sun to compute new density, pressure and temperature profiles, using polytrope modelling of the equation of state for the matter. These results should be applied to a re-analysis of solar neutrino production, and to stellar evolution in general.

  18. Nature, theory and modelling of geophysical convective planetary boundary layers

    Science.gov (United States)

    Zilitinkevich, Sergej

    2015-04-01

    Geophysical convective planetary boundary layers (CPBLs) are still poorly reproduced in oceanographic, hydrological and meteorological models. Besides the mean flow and usual shear-generated turbulence, CPBLs involve two types of motion disregarded in conventional theories: 'anarchy turbulence' comprised of the buoyancy-driven plumes, merging to form larger plumes instead of breaking down, as postulated in conventional theory (Zilitinkevich, 1973), large-scale organised structures fed by the potential energy of unstable stratification through inverse energy transfer in convective turbulence (and performing non-local transports irrespective of mean gradients of transporting properties). C-PBLs are strongly mixed and go on growing as long as the boundary layer remains unstable. Penetration of the mixed layer into the weakly turbulent, stably stratified free flow causes turbulent transports through the CPBL outer boundary. The proposed theory, taking into account the above listed features of CPBL, is based on the following recent developments: prognostic CPBL-depth equation in combination with diagnostic algorithm for turbulence fluxes at the CPBL inner and outer boundaries (Zilitinkevich, 1991, 2012, 2013; Zilitinkevich et al., 2006, 2012), deterministic model of self-organised convective structures combined with statistical turbulence-closure model of turbulence in the CPBL core (Zilitinkevich, 2013). It is demonstrated that the overall vertical transports are performed mostly by turbulence in the surface layer and entrainment layer (at the CPBL inner and outer boundaries) and mostly by organised structures in the CPBL core (Hellsten and Zilitinkevich, 2013). Principal difference between structural and turbulent mixing plays an important role in a number of practical problems: transport and dispersion of admixtures, microphysics of fogs and clouds, etc. The surface-layer turbulence in atmospheric and marine CPBLs is strongly enhanced by the velocity shears in

  19. Eye growth and myopia development: Unifying theory and Matlab model.

    Science.gov (United States)

    Hung, George K; Mahadas, Kausalendra; Mohammad, Faisal

    2016-03-01

    The aim of this article is to present an updated unifying theory of the mechanisms underlying eye growth and myopia development. A series of model simulation programs were developed to illustrate the mechanism of eye growth regulation and myopia development. Two fundamental processes are presumed to govern the relationship between physiological optics and eye growth: genetically pre-programmed signaling and blur feedback. Cornea/lens is considered to have only a genetically pre-programmed component, whereas eye growth is considered to have both a genetically pre-programmed and a blur feedback component. Moreover, based on the Incremental Retinal-Defocus Theory (IRDT), the rate of change of blur size provides the direction for blur-driven regulation. The various factors affecting eye growth are shown in 5 simulations: (1 - unregulated eye growth): blur feedback is rendered ineffective, as in the case of form deprivation, so there is only genetically pre-programmed eye growth, generally resulting in myopia; (2 - regulated eye growth): blur feedback regulation demonstrates the emmetropization process, with abnormally excessive or reduced eye growth leading to myopia and hyperopia, respectively; (3 - repeated near-far viewing): simulation of large-to-small change in blur size as seen in the accommodative stimulus/response function, and via IRDT as well as nearwork-induced transient myopia (NITM), leading to the development of myopia; (4 - neurochemical bulk flow and diffusion): release of dopamine from the inner plexiform layer of the retina, and the subsequent diffusion and relay of neurochemical cascade show that a decrease in dopamine results in a reduction of proteoglycan synthesis rate, which leads to myopia; (5 - Simulink model): model of genetically pre-programmed signaling and blur feedback components that allows for different input functions to simulate experimental manipulations that result in hyperopia, emmetropia, and myopia. These model simulation programs

  20. Bayesian item fit analysis for unidimensional item response theory models.

    Science.gov (United States)

    Sinharay, Sandip

    2006-11-01

    Assessing item fit for unidimensional item response theory models for dichotomous items has always been an issue of enormous interest, but there exists no unanimously agreed item fit diagnostic for these models, and hence there is room for further investigation of the area. This paper employs the posterior predictive model-checking method, a popular Bayesian model-checking tool, to examine item fit for the above-mentioned models. An item fit plot, comparing the observed and predicted proportion-correct scores of examinees with different raw scores, is suggested. This paper also suggests how to obtain posterior predictive p-values (which are natural Bayesian p-values) for the item fit statistics of Orlando and Thissen that summarize numerically the information in the above-mentioned item fit plots. A number of simulation studies and a real data application demonstrate the effectiveness of the suggested item fit diagnostics. The suggested techniques seem to have adequate power and reasonable Type I error rate, and psychometricians will find them promising.

  1. Theory and modeling of cylindrical thermo-acoustic transduction

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Lihong, E-mail: lhtong@ecjtu.edu.cn [School of Civil Engineering and Architecture, East China Jiaotong University, Nanchang, Jiangxi (China); Lim, C.W. [Department of Architecture and Civil Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR (China); Zhao, Xiushao; Geng, Daxing [School of Civil Engineering and Architecture, East China Jiaotong University, Nanchang, Jiangxi (China)

    2016-06-03

    Models both for solid and thinfilm-solid cylindrical thermo-acoustic transductions are proposed and the corresponding acoustic pressure solutions are obtained. The acoustic pressure for an individual carbon nanotube (CNT) as a function of input power is investigated analytically and it is verified by comparing with the published experimental data. Further numerical analysis on the acoustic pressure response and characteristics for varying input frequency and distance are also examined both for solid and thinfilm-solid cylindrical thermo-acoustic transductions. Through detailed theoretical and numerical studies on the acoustic pressure solution for thinfilm-solid cylindrical transduction, it is concluded that a solid with smaller thermal conductivity favors to improve the acoustic performance. In general, the proposed models are applicable to a variety of cylindrical thermo-acoustic devices performing in different gaseous media. - Highlights: • Theory and modeling both for solid and thinfilm-solid cylindrical thermo-acoustic transductions are proposed. • The modeling is verified by comparing with the published experimental data. • Acoustic response characteristics of cylindrical thermo-acoustic transductions are predicted by the proposed model.

  2. Logic models: a useful way to study theories of evaluation practice?

    Science.gov (United States)

    Miller, Robin Lin

    2013-06-01

    This paper comments on the papers in the special volume on logic modeling and evaluation theory. Logic modeling offers a potentially useful approach to learning about the assumptions, activities, and consequences described in an evaluation theory and may facilitate comparative analysis of evaluation theories. However, logic models are imperfect vehicles for depicting the contingent and dynamic nature of evaluation theories. Alternative approaches to studying theories are necessary to capture the essence of theories as they may work in actual practice. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Multiscale Multiphysics and Multidomain Models I: Basic Theory.

    Science.gov (United States)

    Wei, Guo-Wei

    2013-12-01

    This work extends our earlier two-domain formulation of a differential geometry based multiscale paradigm into a multidomain theory, which endows us the ability to simultaneously accommodate multiphysical descriptions of aqueous chemical, physical and biological systems, such as fuel cells, solar cells, nanofluidics, ion channels, viruses, RNA polymerases, molecular motors and large macromolecular complexes. The essential idea is to make use of the differential geometry theory of surfaces as a natural means to geometrically separate the macroscopic domain of solvent from the microscopic domain of solute, and dynamically couple continuum and discrete descriptions. Our main strategy is to construct energy functionals to put on an equal footing of multiphysics, including polar (i.e., electrostatic) solvation, nonpolar solvation, chemical potential, quantum mechanics, fluid mechanics, molecular mechanics, coarse grained dynamics and elastic dynamics. The variational principle is applied to the energy functionals to derive desirable governing equations, such as multidomain Laplace-Beltrami (LB) equations for macromolecular morphologies, multidomain Poisson-Boltzmann (PB) equation or Poisson equation for electrostatic potential, generalized Nernst-Planck (NP) equations for the dynamics of charged solvent species, generalized Navier-Stokes (NS) equation for fluid dynamics, generalized Newton's equations for molecular dynamics (MD) or coarse-grained dynamics and equation of motion for elastic dynamics. Unlike the classical PB equation, our PB equation is an integral-differential equation due to solvent-solute interactions. To illustrate the proposed formalism, we have explicitly constructed three models, a multidomain solvation model, a multidomain charge transport model and a multidomain chemo-electro-fluid-MD-elastic model. Each solute domain is equipped with distinct surface tension, pressure, dielectric function, and charge density distribution. In addition to long

  4. Linking Simple Economic Theory Models and the Cointegrated Vector AutoRegressive Model

    DEFF Research Database (Denmark)

    Møller, Niels Framroze

    This paper attempts to clarify the connection between simple economic theory models and the approach of the Cointegrated Vector-Auto-Regressive model (CVAR). By considering (stylized) examples of simple static equilibrium models, it is illustrated in detail, how the theoretical model and its stru....... Further fundamental extensions and advances to more sophisticated theory models, such as those related to dynamics and expectations (in the structural relations) are left for future papers......This paper attempts to clarify the connection between simple economic theory models and the approach of the Cointegrated Vector-Auto-Regressive model (CVAR). By considering (stylized) examples of simple static equilibrium models, it is illustrated in detail, how the theoretical model and its......, it is demonstrated how other controversial hypotheses such as Rational Expectations can be formulated directly as restrictions on the CVAR-parameters. A simple example of a "Neoclassical synthetic" AS-AD model is also formulated. Finally, the partial- general equilibrium distinction is related to the CVAR as well...

  5. Lorentz Violation of the Photon Sector in Field Theory Models

    Directory of Open Access Journals (Sweden)

    Lingli Zhou

    2014-01-01

    Full Text Available We compare the Lorentz violation terms of the pure photon sector between two field theory models, namely, the minimal standard model extension (SME and the standard model supplement (SMS. From the requirement of the identity of the intersection for the two models, we find that the free photon sector of the SMS can be a subset of the photon sector of the minimal SME. We not only obtain some relations between the SME parameters but also get some constraints on the SMS parameters from the SME parameters. The CPT-odd coefficients (kAFα of the SME are predicted to be zero. There are 15 degrees of freedom in the Lorentz violation matrix Δαβ of free photons of the SMS related with the same number of degrees of freedom in the tensor coefficients (kFαβμν, which are independent from each other in the minimal SME but are interrelated in the intersection of the SMS and the minimal SME. With the related degrees of freedom, we obtain the conservative constraints (2σ on the elements of the photon Lorentz violation matrix. The detailed structure of the photon Lorentz violation matrix suggests some applications to the Lorentz violation experiments for photons.

  6. Game Theory: Trust Model for Common Criteria Certifications & Evaluations

    Directory of Open Access Journals (Sweden)

    Mohd Anuar Mat Isa

    2015-05-01

    Full Text Available International standard and certification play major role in product distributions and marketing activities. To be well accepted in global market, all IT products and services require international evaluation and certification such as Common Criteria (CC certification. This paper discusses some of the security, trust and privacy issues in Common Criteria that would happen during evaluation and certification of IT products and services. Our main intention is to help interested stake holders in choosing a finest authorizing member of CC certification for IT products and services using our new trust model. The proposed trust models takes into account the dynamically changing international relationship among nations which produces an index value during selection of finest CC authorizing member. The trust models use game theory to identify the finest CC authorizing member. We hope to contribute to this area of research by lessening the “cost to market” of IT products and related services. It is anticipated that it would give positive impact on global business transaction by having better and wider acceptability using our models in the selection of the finest CC authorizing member, CC consumer, and vendor (manufacturer.

  7. Stakeholder Theory and Value Creation Models in Brazilian Firms

    Directory of Open Access Journals (Sweden)

    Natalia Giugni Vidal

    2015-09-01

    Full Text Available Objective – The purpose of this study is to understand how top Brazilian firms think about and communicate value creation to their stakeholders. Design/methodology/approach – We use qualitative content analysis methodology to analyze the sustainability or annual integrated reports of the top 25 Brazilian firms by sales revenue. Findings – Based on our analysis, these firms were classified into three main types of stakeholder value creation models: narrow, broad, or transitioning from narrow to broad. We find that many of the firms in our sample are in a transition state between narrow and broad stakeholder value creation models. We also identify seven areas of concentration discussed by firms in creating value for stakeholders: better stakeholder relationships, better work environment, environmental preservation, increased customer base, local development, reputation, and stakeholder dialogue. Practical implications – This study shows a trend towards broader stakeholder value creation models in Brazilian firms. The findings of this study may inform practitioners interested in broadening their value creation models. Originality/value – This study adds to the discussion of stakeholder theory in the Brazilian context by understanding variations in value creation orientation in Brazil.

  8. A New Theory-to-Practice Model for Student Affairs: Integrating Scholarship, Context, and Reflection

    Science.gov (United States)

    Reason, Robert D.; Kimball, Ezekiel W.

    2012-01-01

    In this article, we synthesize existing theory-to-practice approaches within the student affairs literature to arrive at a new model that incorporates formal and informal theory, institutional context, and reflective practice. The new model arrives at a balance between the rigor necessary for scholarly theory development and the adaptability…

  9. A Knot Model Sugugested by the Standard Electroweak Theory

    CERN Document Server

    Finkelstein, R J

    2004-01-01

    We attempt to go beyond the standard electroweak theory by replacing the underlying Lie algebra with its q-deformation: SU_q(2) x SU(1). This step introduces new degrees of freedom that we interpret as indicative of non-locality and as a possible basis for a solitonic model of the elementary particles. The solitons are conjectured to be knotted flux tubes labelled by the irreducible representations of SU_q(2), an algebra which is not only closely related to the standard theory but also plays a role in the description of knots. Each of the four families of elementary fermions is conujectured to be represented by one of the four possible trefoils. The three individual fermions belonging to any family then occupy the three lowest states in the excitation spectrum of the trefoil for that family. The dimensionless deformation parameter, q, is assumed to be a function of the Higgs field and to be an effective measure of the influence of the new degrees of freedom introduced by the deformation of SU(2). One finds a ...

  10. Partial differential equations in action from modelling to theory

    CERN Document Server

    Salsa, Sandro

    2016-01-01

    The book is intended as an advanced undergraduate or first-year graduate course for students from various disciplines, including applied mathematics, physics and engineering. It has evolved from courses offered on partial differential equations (PDEs) over the last several years at the Politecnico di Milano. These courses had a twofold purpose: on the one hand, to teach students to appreciate the interplay between theory and modeling in problems arising in the applied sciences, and on the other to provide them with a solid theoretical background in numerical methods, such as finite elements. Accordingly, this textbook is divided into two parts. The first part, chapters 2 to 5, is more elementary in nature and focuses on developing and studying basic problems from the macro-areas of diffusion, propagation and transport, waves and vibrations. In turn the second part, chapters 6 to 11, concentrates on the development of Hilbert spaces methods for the variational formulation and the analysis of (mainly) linear bo...

  11. Partial differential equations in action from modelling to theory

    CERN Document Server

    Salsa, Sandro

    2015-01-01

    The book is intended as an advanced undergraduate or first-year graduate course for students from various disciplines, including applied mathematics, physics and engineering. It has evolved from courses offered on partial differential equations (PDEs) over the last several years at the Politecnico di Milano. These courses had a twofold purpose: on the one hand, to teach students to appreciate the interplay between theory and modeling in problems arising in the applied sciences, and on the other to provide them with a solid theoretical background in numerical methods, such as finite elements. Accordingly, this textbook is divided into two parts. The first part, chapters 2 to 5, is more elementary in nature and focuses on developing and studying basic problems from the macro-areas of diffusion, propagation and transport, waves and vibrations. In turn the second part, chapters 6 to 11, concentrates on the development of Hilbert spaces methods for the variational formulation and the analysis of (mainly) linear bo...

  12. Nonequilibrium Anderson model made simple with density functional theory

    Science.gov (United States)

    Kurth, S.; Stefanucci, G.

    2016-12-01

    The single-impurity Anderson model is studied within the i-DFT framework, a recently proposed extension of density functional theory (DFT) for the description of electron transport in the steady state. i-DFT is designed to give both the steady current and density at the impurity, and it requires the knowledge of the exchange-correlation (xc) bias and on-site potential (gate). In this work we construct an approximation for both quantities which is accurate in a wide range of temperatures, gates, and biases, thus providing a simple and unifying framework to calculate the differential conductance at negligible computational cost in different regimes. Our results mark a substantial advance for DFT and may inform the construction of functionals applicable to other correlated systems.

  13. Basic first-order model theory in Mizar

    Directory of Open Access Journals (Sweden)

    Marco Bright Caminati

    2010-01-01

    Full Text Available The author has submitted to Mizar Mathematical Library a series of five articles introducing a framework for the formalization of classical first-order model theory.In them, Goedel's completeness and Lowenheim-Skolem theorems have also been formalized for the countable case, to offer a first application of it and to showcase its utility.This is an overview and commentary on some key aspects of this setup.It features exposition and discussion of a new encoding of basic definitions and theoretical gears needed for the task, remarks about the design strategies and approaches adopted in their implementation, and more general reflections about proof checking induced by the work done.

  14. Probing flame chemistry with MBMS, theory, and modeling

    Energy Technology Data Exchange (ETDEWEB)

    Westmoreland, P.R. [Univ. of Massachusetts, Amherst (United States)

    1993-12-01

    The objective is to establish kinetics of combustion and molecular-weight growth in C{sub 3} hydrocarbon flames as part of an ongoing study of flame chemistry. Specific reactions being studied are (1) the growth reactions of C{sub 3}H{sub 5} and C{sub 3}H{sub 3} with themselves and with unsaturated hydrocarbons and (2) the oxidation reactions of O and OH with C{sub 3}`s. This approach combines molecular-beam mass spectrometry (MBMS) experiments on low-pressure flat flames; theoretical predictions of rate constants by thermochemical kinetics, Bimolecular Quantum-RRK, RRKM, and master-equation theory; and whole-flame modeling using full mechanisms of elementary reactions.

  15. Unitary theory of pion photoproduction in the chiral bag model

    Energy Technology Data Exchange (ETDEWEB)

    Araki, M.; Afnan, I.R.

    1987-07-01

    We present a multichannel unitary theory of single pion photoproduction from a baryon B. Here, B is the nucleon or ..delta..(1232), with possible extension to include the Roper resonance and strange baryons. We treat the baryon as a three-quark state within the framework of the gauge and chiral Lagrangian, derived from the Lagrangian for the chiral bag model. By first exposing two-body, and then three-body unitarity, taking into consideration the ..pi pi..B and ..gamma pi..B intermediate states, we derive a set of equations for the amplitudes both on and off the energy shell. The Born term in the expansion of the amplitude has the new feature that the vertices in the pole diagram are undressed, while those in the crossed, contact, and pion pole diagrams are dressed.

  16. Unitary theory of pion photoproduction in the chiral bag model

    Science.gov (United States)

    Araki, M.; Afnan, I. R.

    1987-07-01

    We present a multichannel unitary theory of single pion photoproduction from a baryon B. Here, B is the nucleon or Δ(1232), with possible extension to include the Roper resonance and strange baryons. We treat the baryon as a three-quark state within the framework of the gauge and chiral Lagrangian, derived from the Lagrangian for the chiral bag model. By first exposing two-body, and then three-body unitarity, taking into consideration the ππB and γπB intermediate states, we derive a set of equations for the amplitudes both on and off the energy shell. The Born term in the expansion of the amplitude has the new feature that the vertices in the pole diagram are undressed, while those in the crossed, contact, and pion pole diagrams are dressed.

  17. Dynamic density functional theory of solid tumor growth: Preliminary models

    Directory of Open Access Journals (Sweden)

    Arnaud Chauviere

    2012-03-01

    Full Text Available Cancer is a disease that can be seen as a complex system whose dynamics and growth result from nonlinear processes coupled across wide ranges of spatio-temporal scales. The current mathematical modeling literature addresses issues at various scales but the development of theoretical methodologies capable of bridging gaps across scales needs further study. We present a new theoretical framework based on Dynamic Density Functional Theory (DDFT extended, for the first time, to the dynamics of living tissues by accounting for cell density correlations, different cell types, phenotypes and cell birth/death processes, in order to provide a biophysically consistent description of processes across the scales. We present an application of this approach to tumor growth.

  18. Theories and models on the biological of cells in space

    Science.gov (United States)

    Todd, P.; Klaus, D. M.

    1996-01-01

    A wide variety of observations on cells in space, admittedly made under constraining and unnatural conditions in may cases, have led to experimental results that were surprising or unexpected. Reproducibility, freedom from artifacts, and plausibility must be considered in all cases, even when results are not surprising. The papers in symposium on 'Theories and Models on the Biology of Cells in Space' are dedicated to the subject of the plausibility of cellular responses to gravity -- inertial accelerations between 0 and 9.8 m/sq s and higher. The mechanical phenomena inside the cell, the gravitactic locomotion of single eukaryotic and prokaryotic cells, and the effects of inertial unloading on cellular physiology are addressed in theoretical and experimental studies.

  19. Theory and model of water resources complex adaptive allocation system

    Institute of Scientific and Technical Information of China (English)

    ZHAOJianshi; WANGZhongjing; WENGWenbin

    2003-01-01

    Complex adaptive system theory is a new and important embranchment of system science,which provides a new thought to research water resources allocation system.Based on the analysis of complexity and complex adaptive mechanism of water resources allocation system,a fire-new analysis model is presented in this paper.With the description of Dynamical mechanism of system,behavior characters of agents and the evalustion method of system status,an integrity research system is built to analyse the evolvement rule of water resources allocation system.And a brief research for the impact of water resources allocation in beneficial regions of the Water Transfer from south to North China Project is conducted.

  20. The Five-Factor Model and Self-Determination Theory

    DEFF Research Database (Denmark)

    Olesen, Martin Hammershøj; Thomsen, Dorthe Kirkegaard; Schnieber, Anette;

    questionnaires of personality traits (NEO-FFI) and causality orientations (GCOS). To test whether covariance between traits and orientations could be attributed to shared or separate latent variables we conducted joint factor analyses. Results reveal that the Autonomy orientation can be distinguished from......This study investigates conceptual overlap vs. distinction between individual differences in personality traits, i.e. the Five-Factor Model; and Self-determination Theory, i.e. general causality orientations. Twelve-hundred-and-eighty-seven freshmen (mean age 21.71; 64% women) completed electronic...... related personality traits. The Control orientation shares a latent variable with reversed Agreeableness. The Impersonal orientation shows both overlapping and distinct features with Neuroticism. Results are discussed in relation to an integrative understanding of traits and orientations....

  1. Theories and models on the Biology of Cells in Space

    Science.gov (United States)

    Todd, P.; Klaus, D. M.

    A wide variety of observations on cells in space, admittedly made under constraining and unnatural conditions in many cases, have led to experimental results that were surprising or unexpected. Reproducibility, freedom from artifacts, and plausibility must be considered in all cases, even when results are not surprising. The papers in the symposium on ``Theories and Models on the Biology of Cells in Space'' are dedicated to the subject of theplausibility of cellular responses to gravity -- inertial accelerations between 0 and 9.8 m/s^2 and higher. The mechanical phenomena inside the cell, the gravitactic locomotion of single eukaryotic and prokaryotic cells, and the effects of inertial unloading on cellular physiology are addressed in theoretical and experimental studies.

  2. Computer Models and Automata Theory in Biology and Medicine

    CERN Document Server

    Baianu, I C

    2004-01-01

    The applications of computers to biological and biomedical problem solving goes back to the very beginnings of computer science, automata theory [1], and mathematical biology [2]. With the advent of more versatile and powerful computers, biological and biomedical applications of computers have proliferated so rapidly that it would be virtually impossible to compile a comprehensive review of all developments in this field. Limitations of computer simulations in biology have also come under close scrutiny, and claims have been made that biological systems have limited information processing power [3]. Such general conjectures do not, however, deter biologists and biomedical researchers from developing new computer applications in biology and medicine. Microprocessors are being widely employed in biological laboratories both for automatic data acquisition/processing and modeling; one particular area, which is of great biomedical interest, involves fast digital image processing and is already established for rout...

  3. Lattice gauge theory of three dimensional Thirring model

    CERN Document Server

    Kim, S; Kim, Seyong; Kim, Yoonbai

    1999-01-01

    Three dimensional Thirring model with N four-component Dirac fermions, reformulated as a lattice gauge theory, is studied by computer simulation. According to an 8^{3} data and preliminary 16^3 data, chiral symmetry is found to be spontaneously broken for N=2,\\;4 and 6. N=2 data exhibits long tail of the non-vanishing chiral condensate into weak coupling region, and N=6 case shows phase separation between the strong coupling region and the weak coupling region. Although the comparison between 8^3 data and 16^3 data shows large finite volume effects, an existence of the critical fermion flavor number N_{{\\rm cr}} (2

  4. Generalized Potts-Models and their Relevance for Gauge Theories

    Directory of Open Access Journals (Sweden)

    Andreas Wipf

    2007-01-01

    Full Text Available We study the Polyakov loop dynamics originating from finite-temperature Yang-Mills theory. The effective actions contain center-symmetric terms involving powers of the Polyakov loop, each with its own coupling. For a subclass with two couplings we perform a detailed analysis of the statistical mechanics involved. To this end we employ a modified mean field approximation and Monte Carlo simulations based on a novel cluster algorithm. We find excellent agreement of both approaches. The phase diagram exhibits both first and second order transitions between symmetric, ferromagnetic and antiferromagnetic phases with phase boundaries merging at three tricritical points. The critical exponents ν and γ at the continuous transition between symmetric and antiferromagnetic phases are the same as for the 3-state spin Potts model.

  5. Theory, Modeling and Simulation: Research progress report 1994--1995

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, B.C.; Dixon, D.A.; Dunning, T.H.

    1997-01-01

    The Pacific Northwest National Laboratory (PNNL) has established the Environmental Molecular Sciences Laboratory (EMSL). In April 1994, construction began on the new EMSL, a collaborative research facility devoted to advancing the understanding of environmental molecular science. Research in the Theory, Modeling, and Simulation (TM and S) program will play a critical role in understanding molecular processes important in restoring DOE`s research, development, and production sites, including understanding the migration and reactions of contaminants in soils and ground water, developing processes for isolation and processing of pollutants, developing improved materials for waste storage, understanding the enzymatic reactions involved in the biodegradation of contaminants, and understanding the interaction of hazardous chemicals with living organisms. The research objectives of the TM and S program are fivefold: to apply available electronic structure and dynamics techniques to study fundamental molecular processes involved in the chemistry of natural and contaminated systems; to extend current electronic structure and dynamics techniques to treat molecular systems of future importance and to develop new techniques for addressing problems that are computationally intractable at present; to apply available molecular modeling techniques to simulate molecular processes occurring in the multi-species, multi-phase systems characteristic of natural and polluted environments; to extend current molecular modeling techniques to treat ever more complex molecular systems and to improve the reliability and accuracy of such simulations; and to develop technologies for advanced parallel architectural computer systems. Research highlights of 82 projects are given.

  6. Optimization models using fuzzy sets and possibility theory

    CERN Document Server

    Orlovski, S

    1987-01-01

    Optimization is of central concern to a number of discip­ lines. Operations Research and Decision Theory are often consi­ dered to be identical with optimizationo But also in other areas such as engineering design, regional policy, logistics and many others, the search for optimal solutions is one of the prime goals. The methods and models which have been used over the last decades in these areas have primarily been "hard" or "crisp", i. e. the solutions were considered to be either fea­ sible or unfeasible, either above a certain aspiration level or below. This dichotomous structure of methods very often forced the modeller to approximate real problem situations of the more-or-less type by yes-or-no-type models, the solutions of which might turn out not to be the solutions to the real prob­ lems. This is particularly true if the problem under considera­ tion includes vaguely defined relationships, human evaluations, uncertainty due to inconsistent or incomplete evidence, if na­ tural language has to be...

  7. SUSY Breaking in Local String/F-Theory Models

    CERN Document Server

    Blumenhagen, R; Krippendorf, S; Moster, S; Quevedo, F

    2009-01-01

    We investigate bulk moduli stabilisation and supersymmetry breaking in local string/F-theory models where the Standard Model is supported on a del Pezzo surface or singularity. Computing the gravity mediated soft terms on the Standard Model brane induced by bulk supersymmetry breaking in the LARGE volume scenario, we explicitly find suppressions by M_s/M_P ~ V^{-1/2} compared to M_{3/2}. This gives rise to several phenomenological scenarios, depending on the strength of perturbative corrections to the effective action and the source of de Sitter lifting, in which the soft terms are suppressed by at least M_P/V^{3/2} and may be as small as M_P/V^2. Since the gravitino mass is of order M_{3/2} ~ M_P/V, for TeV soft terms all these scenarios give a very heavy gravitino (M_{3/2} >= 10^8 GeV) and generically the lightest moduli field is also heavy enough (m >= 10 TeV) to avoid the cosmological moduli problem. For TeV soft terms, these scenarios predict a minimal value of the volume to be V ~ 10^{6-7} in string uni...

  8. Super no-scale models in string theory

    Science.gov (United States)

    Kounnas, Costas; Partouche, Hervé

    2016-12-01

    We consider "super no-scale models" in the framework of the heterotic string, where the N = 4 , 2 , 1 → 0 spontaneous breaking of supersymmetry is induced by geometrical fluxes realizing a stringy Scherk-Schwarz perturbative mechanism. Classically, these backgrounds are characterized by a boson/fermion degeneracy at the massless level, even if supersymmetry is broken. At the 1-loop level, the vacuum energy is exponentially suppressed, provided the supersymmetry breaking scale is small, m3/2 ≪Mstring. We show that the "super no-scale string models" under consideration are free of Hagedorn-like tachyonic singularities, even when the supersymmetry breaking scale is large, m3/2 ≃Mstring. The vacuum energy decreases monotonically and converges exponentially to zero, when m3/2 varies from Mstring to 0. We also show that all Wilson lines associated to asymptotically free gauge symmetries are dynamically stabilized by the 1-loop effective potential, while those corresponding to non-asymptotically free gauge groups lead to instabilities and condense. The Wilson lines of the conformal gauge symmetries remain massless. When stable, the stringy super no-scale models admit low energy effective actions, where decoupling gravity yields theories in flat spacetime, with softly broken supersymmetry.

  9. Comparing Multiple Discrepancies Theory to Affective Models of Subjective Wellbeing

    Science.gov (United States)

    Blore, Jed D.; Stokes, Mark A.; Mellor, David; Firth, Lucy; Cummins, Robert A.

    2011-01-01

    The Subjective Wellbeing (SWB) literature is replete with competing theories detailing the mechanisms underlying the construction and maintenance of SWB. The current study aimed to compare and contrast two of these approaches: multiple discrepancies theory (MDT) and an affective-cognitive theory of SWB. MDT posits SWB to be the result of perceived…

  10. Low-Energy Effective Theories of Quantum Link and Quantum Spin Models

    CERN Document Server

    Schlittgen, B

    2001-01-01

    Quantum spin and quantum link models provide an unconventional regularization of field theory in which classical fields arise via dimensional reduction of discrete variables. This D-theory regularization leads to the same continuum theories as the conventional approach. We show this by deriving the low-energy effective Lagrangians of D-theory models using coherent state path integral techniques. We illustrate our method for the $(2+1)$-d Heisenberg quantum spin model which is the D-theory regularization of the 2-d O(3) model. Similarly, we prove that in the continuum limit a $(2+1)$-d quantum spin model with $SU(N)_L\\times SU(N)_R\\times U(1)_{L=R}$ symmetry is equivalent to the 2-d principal chiral model. Finally, we show that $(4+1)$-d SU(N) quantum link models reduce to ordinary 4-d Yang-Mills theory.

  11. Attachment Theory and Theory of Planned Behavior: An Integrative Model Predicting Underage Drinking

    Science.gov (United States)

    Lac, Andrew; Crano, William D.; Berger, Dale E.; Alvaro, Eusebio M.

    2013-01-01

    Research indicates that peer and maternal bonds play important but sometimes contrasting roles in the outcomes of children. Less is known about attachment bonds to these 2 reference groups in young adults. Using a sample of 351 participants (18 to 20 years of age), the research integrated two theoretical traditions: attachment theory and theory of…

  12. Attachment Theory and Theory of Planned Behavior: An Integrative Model Predicting Underage Drinking

    Science.gov (United States)

    Lac, Andrew; Crano, William D.; Berger, Dale E.; Alvaro, Eusebio M.

    2013-01-01

    Research indicates that peer and maternal bonds play important but sometimes contrasting roles in the outcomes of children. Less is known about attachment bonds to these 2 reference groups in young adults. Using a sample of 351 participants (18 to 20 years of age), the research integrated two theoretical traditions: attachment theory and theory of…

  13. Relationships among Classical Test Theory and Item Response Theory Frameworks via Factor Analytic Models

    Science.gov (United States)

    Kohli, Nidhi; Koran, Jennifer; Henn, Lisa

    2015-01-01

    There are well-defined theoretical differences between the classical test theory (CTT) and item response theory (IRT) frameworks. It is understood that in the CTT framework, person and item statistics are test- and sample-dependent. This is not the perception with IRT. For this reason, the IRT framework is considered to be theoretically superior…

  14. Cohomological gauge theory, quiver matrix models and Donaldson-Thomas theory

    Energy Technology Data Exchange (ETDEWEB)

    Cirafici, Michele [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands)], E-mail: m.cirafici@uu.nl; Sinkovics, Annamaria [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)], E-mail: a.sinkovics@damtp.cam.ac.uk; Szabo, Richard J. [Department of Mathematics, Heriot-Watt University and Maxwell Institute for Mathematical Sciences, Colin Maclaurin Building, Riccarton, Edinburgh EH14 4AS (United Kingdom)], E-mail: r.j.szabo@ma.hw.ac.uk

    2009-03-11

    We study the relation between Donaldson-Thomas theory of Calabi-Yau threefolds and a six-dimensional topological Yang-Mills theory. Our main example is the topological U(N) gauge theory on flat space in its Coulomb branch. To evaluate its partition function we use equivariant localization techniques on its noncommutative deformation. As a result the gauge theory localizes on noncommutative instantons which can be classified in terms of N-coloured three-dimensional Young diagrams. We give to these noncommutative instantons a geometrical description in terms of certain stable framed coherent sheaves on projective space by using a higher-dimensional generalization of the ADHM formalism. From this formalism we construct a topological matrix quantum mechanics which computes an index of BPS states and provides an alternative approach to the six-dimensional gauge theory.

  15. A practitioner's guide to persuasion: an overview of 15 selected persuasion theories, models and frameworks.

    Science.gov (United States)

    Cameron, Kenzie A

    2009-03-01

    To provide a brief overview of 15 selected persuasion theories and models, and to present examples of their use in health communication research. The theories are categorized as message effects models, attitude-behavior approaches, cognitive processing theories and models, consistency theories, inoculation theory, and functional approaches. As it is often the intent of a practitioner to shape, reinforce, or change a patient's behavior, familiarity with theories of persuasion may lead to the development of novel communication approaches with existing patients. This article serves as an introductory primer to theories of persuasion with applications to health communication research. Understanding key constructs and general formulations of persuasive theories may allow practitioners to employ useful theoretical frameworks when interacting with patients.

  16. Implicit Theories Relate to Youth Psychopathology, But How? A Longitudinal Test of Two Predictive Models.

    Science.gov (United States)

    Schleider, Jessica L; Weisz, John R

    2016-08-01

    Research shows relations between entity theories-i.e., beliefs that traits and abilities are unchangeable-and youth psychopathology. A common interpretation has been that entity theories lead to psychopathology, but another possibility is that psychopathology predicts entity theories. The two models carry different implications for developmental psychopathology and intervention design. We tested each model's plausibility, examining longitudinal associations between entity theories of thoughts, feelings, and behavior and psychopathology in early adolescents across one school year (N = 59, 52 % female, ages 11-14, 0 % attrition). Baseline entity theories did not predict increases in psychopathology; instead, baseline psychopathology predicted increased entity theories over time. When symptom clusters were assessed individually, greater youth internalizing (but not externalizing) problems predicted subsequent increases in entity theories. Findings suggest that the commonly proposed predictive model may not be the only one warranting attention. They suggest that youth psychopathology may contribute to the development of certain kinds of entity theories.

  17. The physical theory and propagation model of THz atmospheric propagation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, R; Yao, J Q; Xu, D G; Wang, J L; Wang, P, E-mail: wangran19861014@163.com [College of Precision Instrument and Opto-electronics Engineering, Institute of Laser and Opto-electronics, Tianjin University, Tianjin 300072 (China)

    2011-02-01

    Terahertz (THz) radiation is extensively applied in diverse fields, such as space communication, Earth environment observation, atmosphere science, remote sensing and so on. And the research on propagation features of THz wave in the atmosphere becomes more and more important. This paper firstly illuminates the advantages and outlook of THz in space technology. Then it introduces the theoretical framework of THz atmospheric propagation, including some fundamental physical concepts and processes. The attenuation effect (especially the absorption of water vapor), the scattering of aerosol particles and the effect of turbulent flow mainly influence THz atmosphere propagation. Fundamental physical laws are illuminated as well, such as Lamber-beer law, Mie scattering theory and radiative transfer equation. The last part comprises the demonstration and comparison of THz atmosphere propagation models like Moliere(V5), SARTre and AMATERASU. The essential problems are the deep analysis of physical mechanism of this process, the construction of atmospheric propagation model and databases of every kind of material in the atmosphere, and the standardization of measurement procedures.

  18. Information System Development Model: Theories Analysis and Guidelines

    Science.gov (United States)

    Nayan, Norshita Mat; Badioze Zaman, Halimah

    Development of information system project is one of the IT projects which have been developed to offer the best facilities for publics. Process of system development will go through its own life cycle and every process must be refined in order to fulfill aims and objectives. Eventhough information system development is always correlate with failure but a few key factors will help the systems to succeed. There are multiple success factors being discussed by other researches in the information system development but failure figure still at the higher side. The main purpose of this research is to discuss processes involved in the development of information system which positively contribute towards its success. Model of information system development which has been developed (PADM Model) consists of four fundamental processes; planning, requirement analysis, design and maintenance. All processes will be monitored by a main process namely quality as the key performance indicator. Quality plays a vital role in assessing the ability of information system developed in order to fulfill users' expectations. Analysis of theory can be used as a guideline and measurement base towards the system with hope that percentage of failure will reduce subsequently.

  19. Cognitive performance modeling based on general systems performance theory.

    Science.gov (United States)

    Kondraske, George V

    2010-01-01

    General Systems Performance Theory (GSPT) was initially motivated by problems associated with quantifying different aspects of human performance. It has proved to be invaluable for measurement development and understanding quantitative relationships between human subsystem capacities and performance in complex tasks. It is now desired to bring focus to the application of GSPT to modeling of cognitive system performance. Previous studies involving two complex tasks (i.e., driving and performing laparoscopic surgery) and incorporating measures that are clearly related to cognitive performance (information processing speed and short-term memory capacity) were revisited. A GSPT-derived method of task analysis and performance prediction termed Nonlinear Causal Resource Analysis (NCRA) was employed to determine the demand on basic cognitive performance resources required to support different levels of complex task performance. This approach is presented as a means to determine a cognitive workload profile and the subsequent computation of a single number measure of cognitive workload (CW). Computation of CW may be a viable alternative to measuring it. Various possible "more basic" performance resources that contribute to cognitive system performance are discussed. It is concluded from this preliminary exploration that a GSPT-based approach can contribute to defining cognitive performance models that are useful for both individual subjects and specific groups (e.g., military pilots).

  20. The physical theory and propagation model of THz atmospheric propagation

    Science.gov (United States)

    Wang, R.; Yao, J. Q.; Xu, D. G.; Wang, J. L.; Wang, P.

    2011-02-01

    Terahertz (THz) radiation is extensively applied in diverse fields, such as space communication, Earth environment observation, atmosphere science, remote sensing and so on. And the research on propagation features of THz wave in the atmosphere becomes more and more important. This paper firstly illuminates the advantages and outlook of THz in space technology. Then it introduces the theoretical framework of THz atmospheric propagation, including some fundamental physical concepts and processes. The attenuation effect (especially the absorption of water vapor), the scattering of aerosol particles and the effect of turbulent flow mainly influence THz atmosphere propagation. Fundamental physical laws are illuminated as well, such as Lamber-beer law, Mie scattering theory and radiative transfer equation. The last part comprises the demonstration and comparison of THz atmosphere propagation models like Moliere(V5), SARTre and AMATERASU. The essential problems are the deep analysis of physical mechanism of this process, the construction of atmospheric propagation model and databases of every kind of material in the atmosphere, and the standardization of measurement procedures.

  1. Three findings to model a quantum-gravitational theory

    CERN Document Server

    Alfonso-Faus, Antonio

    2008-01-01

    In 1967 Zeldovich expressed the cosmological constant lambda in terms of G, m and h, the gravitational constant, the mass of a fundamental particle and Plancks constant. In 1972 Weinberg expressed m in terms of h, G, the speed of light c and the Hubble parameter H. We proved that both expressions are identical. We also found proportionality between c and H. The critical mass balancing the outward quantum mechanical spreading of the wave function, and its inward gravitational collapse, has been recently estimated. We identify this mass with Zeldovich and Weinberg mass. A semi classical gravity model is reinforced and provides an insight for the modelling of a quantum-gravitational theory. The time evolution of the peak probability density for a free particle, a wave function initially filling the whole Universe, explains the later geometrical properties of the fundamental particles. We prove that they end up acquiring a constant size given by their Compton wavelength. The size of the fundamental particles, as ...

  2. Theory and Phenomenology of an Exceptional Supersymmetric Standard Model

    CERN Document Server

    King, S F; Nevzorov, R

    2006-01-01

    We make a comprehensive study of the theory and phenomenology of a low energy supersymmetric standard model originating from a string-inspired $E_6$ grand unified gauge group. The Exceptional Supersymmetric Standard Model (ESSM) considered here is based on the low energy SM gauge group together with an extra $Z'$ corresponding to an extra $U(1)_{N}$ gauge symmetry under which right--handed neutrinos have zero charge. The low energy matter content of the ESSM corresponds to three 27 representations of the $E_6$ symmetry group, to ensure anomaly cancellation, plus an additional pair of Higgs--like doublets as required for high energy gauge coupling unification. The ESSM is therefore a low energy alternative to the MSSM or NMSSM. The ESSM involves extra matter beyond the MSSM contained in three $5+5^*$ representations of SU(5), plus three SU(5) singlets which carry $U(1)_{N}$ charges, one of which develops a VEV, providing the effective $\\mu$ term for the Higgs doublets, as well as the necessary exotic fermion m...

  3. Theory and Modeling of Gamma-Ray Pulsars

    Science.gov (United States)

    Yadigaroglu, Ion-Alexis George

    Newborn neutron stars from supernovae explosions radiate brightly in γ rays, outshining all other objects in the Galaxy. The γ rays are emitted in a beam, and a flash of emission is observed at every rotation of the star; hence these objects are called γ-ray pulsars. A great amount of energy is radiated in this form (~ 1035 erg/s), originating from the kinetic energy associated with the rapid (~100 ms) rotation of the neutron star. As this energy is sapped and converted to γ rays, the star slows down, to ~1 s period after a million years. At this time, the γ-ray emission suddenly stops. Driven by the explosion in number and quality of γ-ray pulsar observations with the launch of the EGRET instrument aboard the Compton Gamma Ray Observatory in 1991, we have revisited the theory and modeling of γ-ray pulsars. We adopt a particular point of view in our efforts, refraining from detailed computations of the radiation spectra and looking instead to establish a number of important features of the magnetosphere and emission zones. Building on previous efforts, I have developed an outer gap model of the emission geometry and physics which is successful in explaining many of the key features of the observations. In particular the complex light curves find a natural explanation in this model. Several important puzzles remain and are presented as a challenge for future investigations. If one can successfully model the γ-ray emissions, γ-ray pulsars as a group can be used to explore general properties of our Galaxy. Initial applications of this idea are presented. We enlarge the sample of γ-ray pulsars by searching for associations of unidentified Galactic plane EGRET sources with tracers of massive stars. The characteristics of the candidate identifications are compared to detailed Galactic population syntheses using our pulsar emission model. We find good agreement with model predictions. A constraint is derived on the minimum mass a star must have in order to form

  4. Promising synergies of simulation model management, software engineering, artificial intelligence, and general system theories

    Energy Technology Data Exchange (ETDEWEB)

    Oren, T.I.

    1982-01-01

    Simulation is viewed within the model management paradigm. Major components of simulation systems as well as elements of model management are outlined. Possible synergies of simulation model management, software engineering, artificial intelligence, and general system theories are systematized. 21 references.

  5. From a systems theory of sociology to modeling the onset and evolution of criminality

    CERN Document Server

    Bellomo, N; Knopoff, D; Soler, J

    2014-01-01

    This paper proposes a systems theory approach to the modeling of onset and evolution of criminality in a territory, which aims at capturing the complexity features of social systems. Complexity is related to the fact that individuals have the ability to develop specific heterogeneously distributed strategies, which depend also on those expressed by the other individuals. The modeling is developed by methods of generalized kinetic theory where interactions and decisional processes are modeled by theoretical tools of stochastic game theory.

  6. An extension of the usual model in statistical decision theory with applications to stochastic optimization problems

    NARCIS (Netherlands)

    Balder, E.J.

    1980-01-01

    By employing fundamental results from “geometric” functional analysis and the theory of multifunctions we formulate a general model for (nonsequential) statistical decision theory, which extends Wald's classical model. From central results that hold for the model we derive a general theorem on the e

  7. Models and theories of prescribing decisions: A review and suggested a new model

    Directory of Open Access Journals (Sweden)

    Ali Murshid M

    2017-06-01

    Full Text Available To date, research on the prescribing decisions of physician lacks sound theoretical foundations. In fact, drug prescribing by doctors is a complex phenomenon influenced by various factors. Most of the existing studies in the area of drug prescription explain the process of decision-making by physicians via the exploratory approach rather than theoretical. Therefore, this review is an attempt to suggest a value conceptual model that explains the theoretical linkages existing between marketing efforts, patient and pharmacist and physician decision to prescribe the drugs. The paper follows an inclusive review approach and applies the previous theoretical models of prescribing behaviour to identify the relational factors. More specifically, the report identifies and uses several valuable perspectives such as the ‘persuasion theory - elaboration likelihood model’, the stimuli–response marketing model’, the ‘agency theory’, the theory of planned behaviour,’ and ‘social power theory,’ in developing an innovative conceptual paradigm. Based on the combination of existing methods and previous models, this paper suggests a new conceptual model of the physician decision-making process. This unique model has the potential for use in further research.

  8. Models and theories of prescribing decisions: A review and suggested a new model

    Science.gov (United States)

    Mohaidin, Zurina

    2017-01-01

    To date, research on the prescribing decisions of physician lacks sound theoretical foundations. In fact, drug prescribing by doctors is a complex phenomenon influenced by various factors. Most of the existing studies in the area of drug prescription explain the process of decision-making by physicians via the exploratory approach rather than theoretical. Therefore, this review is an attempt to suggest a value conceptual model that explains the theoretical linkages existing between marketing efforts, patient and pharmacist and physician decision to prescribe the drugs. The paper follows an inclusive review approach and applies the previous theoretical models of prescribing behaviour to identify the relational factors. More specifically, the report identifies and uses several valuable perspectives such as the ‘persuasion theory - elaboration likelihood model’, the stimuli–response marketing model’, the ‘agency theory’, the theory of planned behaviour,’ and ‘social power theory,’ in developing an innovative conceptual paradigm. Based on the combination of existing methods and previous models, this paper suggests a new conceptual model of the physician decision-making process. This unique model has the potential for use in further research. PMID:28690701

  9. Cold and hot cognition: quantum probability theory and realistic psychological modeling.

    Science.gov (United States)

    Corr, Philip J

    2013-06-01

    Typically, human decision making is emotionally "hot" and does not conform to "cold" classical probability (CP) theory. As quantum probability (QP) theory emphasises order, context, superimposition states, and nonlinear dynamic effects, one of its major strengths may be its power to unify formal modeling and realistic psychological theory (e.g., information uncertainty, anxiety, and indecision, as seen in the Prisoner's Dilemma).

  10. On the Methods for Constructing Meson-Baryon Reaction Models within Relativistic Quantum Field Theory

    Energy Technology Data Exchange (ETDEWEB)

    B. Julia-Diaz, H. Kamano, T.-S. H. Lee, A. Matsuyama, T. Sato, N. Suzuki

    2009-04-01

    Within the relativistic quantum field theory, we analyze the differences between the $\\pi N$ reaction models constructed from using (1) three-dimensional reductions of Bethe-Salpeter Equation, (2) method of unitary transformation, and (3) time-ordered perturbation theory. Their relations with the approach based on the dispersion relations of S-matrix theory are dicusssed.

  11. Preservice Biology Teachers' Conceptions About the Tentative Nature of Theories and Models in Biology

    Science.gov (United States)

    Reinisch, Bianca; Krüger, Dirk

    2016-11-01

    In research on the nature of science, there is a need to investigate the role and status of different scientific knowledge forms. Theories and models are two of the most important knowledge forms within biology and are the focus of this study. During interviews, preservice biology teachers (N = 10) were asked about their understanding of theories and models. They were requested to give reasons why they see theories and models as either tentative or certain constructs. Their conceptions were then compared to philosophers' positions (e.g., Popper, Giere). A category system was developed from the qualitative content analysis of the interviews. These categories include 16 conceptions for theories (n tentative = 11; n certain = 5) and 18 conceptions for models (n tentative = 10; n certain = 8). The analysis of the interviews showed that the preservice teachers gave reasons for the tentativeness or certainty of theories and models either due to their understanding of the terms or due to their understanding of the generation or evaluation of theories and models. Therefore, a variety of different terminology, from different sources, should be used in learning-teaching situations. Additionally, an understanding of which processes lead to the generation, evaluation, and refinement or rejection of theories and models should be discussed with preservice teachers. Within philosophy of science, there has been a shift from theories to models. This should be transferred to educational contexts by firstly highlighting the role of models and also their connections to theories.

  12. Models of misbelief: Integrating motivational and deficit theories of delusions.

    Science.gov (United States)

    McKay, Ryan; Langdon, Robyn; Coltheart, Max

    2007-12-01

    The impact of our desires and preferences upon our ordinary, everyday beliefs is well-documented [Gilovich, T. (1991). How we know what isn't so: The fallibility of human reason in everyday life. New York: The Free Press.]. The influence of such motivational factors on delusions, which are instances of pathological misbelief, has tended however to be neglected by certain prevailing models of delusion formation and maintenance. This paper explores a distinction between two general classes of theoretical explanation for delusions; the motivational and the deficit. Motivational approaches view delusions as extreme instances of self-deception; as defensive attempts to relieve pain and distress. Deficit approaches, in contrast, view delusions as the consequence of defects in the normal functioning of belief mechanisms, underpinned by neuroanatomical or neurophysiological abnormalities. It is argued that although there are good reasons to be sceptical of motivational theories (particularly in their more floridly psychodynamic manifestations), recent experiments confirm that motives are important causal forces where delusions are concerned. It is therefore concluded that the most comprehensive account of delusions will involve a theoretical unification of both motivational and deficit approaches.

  13. Recent trends in social systems quantitative theories and quantitative models

    CERN Document Server

    Hošková-Mayerová, Šárka; Soitu, Daniela-Tatiana; Kacprzyk, Janusz

    2017-01-01

    The papers collected in this volume focus on new perspectives on individuals, society, and science, specifically in the field of socio-economic systems. The book is the result of a scientific collaboration among experts from “Alexandru Ioan Cuza” University of Iaşi (Romania), “G. d’Annunzio” University of Chieti-Pescara (Italy), "University of Defence" of Brno (Czech Republic), and "Pablo de Olavide" University of Sevilla (Spain). The heterogeneity of the contributions presented in this volume reflects the variety and complexity of social phenomena. The book is divided in four Sections as follows. The first Section deals with recent trends in social decisions. Specifically, it aims to understand which are the driving forces of social decisions. The second Section focuses on the social and public sphere. Indeed, it is oriented on recent developments in social systems and control. Trends in quantitative theories and models are described in Section 3, where many new formal, mathematical-statistical to...

  14. Sustainable theory of a logistic model - Fisher information approach.

    Science.gov (United States)

    Al-Saffar, Avan; Kim, Eun-Jin

    2017-03-01

    Information theory provides a useful tool to understand the evolution of complex nonlinear systems and their sustainability. In particular, Fisher information has been evoked as a useful measure of sustainability and the variability of dynamical systems including self-organising systems. By utilising Fisher information, we investigate the sustainability of the logistic model for different perturbations in the positive and/or negative feedback. Specifically, we consider different oscillatory modulations in the parameters for positive and negative feedback and investigate their effect on the evolution of the system and Probability Density Functions (PDFs). Depending on the relative time scale of the perturbation to the response time of the system (the linear growth rate), we demonstrate the maintenance of the initial condition for a long time, manifested by a broad bimodal PDF. We present the analysis of Fisher information in different cases and elucidate its implications for the sustainability of population dynamics. We also show that a purely oscillatory growth rate can lead to a finite amplitude solution while self-organisation of these systems can break down with an exponentially growing solution due to the periodic fluctuations in negative feedback. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Exact Maps in Density Functional Theory for Lattice Models

    CERN Document Server

    Dimitrov, Tanja; Fuks, Johanna I; Rubio, Angel

    2015-01-01

    In the present work, we employ exact diagonalization for model systems on a real-space lattice to explicitly construct the exact density-to-potential and for the first time the exact density-to-wavefunction map that underly the Hohenberg-Kohn theorem in density functional theory. Having the explicit wavefunction-to- density map at hand, we are able to construct arbitrary observables as functionals of the ground-state density. We analyze the density-to-potential map as the distance between the fragments of a system increases and the correlation in the system grows. We observe a feature that gradually develops in the density-to-potential map as well as in the density-to-wavefunction map. This feature is inherited by arbitrary expectation values as functional of the ground-state density. We explicitly show the excited-state energies, the excited-state densities, and the correlation entropy as functionals of the ground-state density. All of them show this exact feature that sharpens as the coupling of the fragmen...

  16. Queuing theory models used for port equipment sizing

    Science.gov (United States)

    Dragu, V.; Dinu, O.; Ruscă, A.; Burciu, Ş.; Roman, E. A.

    2017-08-01

    The significant growth of volumes and distances on road transportation led to the necessity of finding solutions to increase water transportation market share together with the handling and transfer technologies within its terminals. It is widely known that the biggest times are consumed within the transport terminals (loading/unloading/transfer) and so the necessity of constantly developing handling techniques and technologies in concordance with the goods flows size so that the total waiting time of ships within ports is reduced. Port development should be achieved by harmonizing the contradictory interests of port administration and users. Port administrators aim profit increase opposite to users that want savings by increasing consumers’ surplus. The difficulty consists in the fact that the transport demand - supply equilibrium must be realised at costs and goods quantities transiting the port in order to satisfy the interests of both parties involved. This paper presents a port equipment sizing model by using queueing theory so that the sum of costs for ships waiting operations and equipment usage would be minimum. Ship operation within the port is assimilated to a mass service waiting system in which parameters are later used to determine the main costs for ships and port equipment.

  17. Density functional theory and dynamical mean-field theory. A way to model strongly correlated systems

    Energy Technology Data Exchange (ETDEWEB)

    Backes, Steffen

    2017-04-15

    The study of the electronic properties of correlated systems is a very diverse field and has lead to valuable insight into the physics of real materials. In these systems, the decisive factor that governs the physical properties is the ratio between the electronic kinetic energy, which promotes delocalization over the lattice, and the Coulomb interaction, which instead favours localized electronic states. Due to this competition, correlated electronic systems can show unique and interesting properties like the Metal-Insulator transition, diverse phase diagrams, strong temperature dependence and in general a high sensitivity to the environmental conditions. A theoretical description of these systems is not an easy task, since perturbative approaches that do not preserve the competition between the kinetic and interaction terms can only be applied in special limiting cases. One of the most famous approaches to obtain the electronic properties of a real material is the ab initio density functional theory (DFT) method. It allows one to obtain the ground state density of the system under investigation by mapping onto an effective non-interacting system that has to be found self-consistently. While being an exact theory, in practical implementations certain approximations have to be made to the exchange-correlation potential. The local density approximation (LDA), which approximates the exchange-correlation contribution to the total energy by that of a homogeneous electron gas with the corresponding density, has proven quite successful in many cases. Though, this approximation in general leads to an underestimation of electronic correlations and is not able to describe a metal-insulator transition due to electronic localization in the presence of strong Coulomb interaction. A different approach to the interacting electronic problem is the dynamical mean-field theory (DMFT), which is non-perturbative in the kinetic and interaction term but neglects all non

  18. A Model for a Grand Theory: Creativity in Art.

    Science.gov (United States)

    McWhinnie, Harold J.

    This paper presents a collection of thoughts and observations about a grand theory of creativity in the arts. The theory elaborated in the paper is based upon the following five major bodies of psychological knowledge and research: (1) hemisphere differences and cerebral lateralization; (2) chemical balance in the brain and bipolar factors; (3)…

  19. Relevance Theory as model for analysing visual and multimodal communication

    NARCIS (Netherlands)

    C. Forceville

    2014-01-01

    Elaborating on my earlier work (Forceville 1996: chapter 5, 2005, 2009; see also Yus 2008), I will here sketch how discussions of visual and multimodal discourse can be embedded in a more general theory of communication and cognition: Sperber and Wilson’s Relevance Theory/RT (Sperber and Wilson 1986

  20. Introduction of the transtheoretical model and organisational development theory in weight management: A narrative review.

    Science.gov (United States)

    Wu, Ya-Ke; Chu, Nain-Feng

    2015-01-01

    Overweight and obesity are serious public health and medical problems among children and adults worldwide. Behavioural change has been demonstrably contributory to weight management programs. Behavioural change-based weight loss programs require a theoretical framework. We will review the transtheoretical model and the organisational development theory in weight management. The transtheoretical model is a behaviour theory of individual level frequently used for weight management programs. The organisational development theory is a more complicated behaviour theory that applies to behavioural change on the system level. Both of these two theories have their respective strengths and weaknesses. In this manuscript, we try to introduce the transtheoretical model and the organisational development theory in the context of weight loss programs among population that are overweight or obese. Ultimately, we wish to present a new framework/strategy of weight management by integrating these two theories together.

  1. Atmospheric boundary layers in storms: advanced theory and modelling applications

    Directory of Open Access Journals (Sweden)

    S. S. Zilitinkevich

    2005-01-01

    Full Text Available Turbulent planetary boundary layers (PBLs control the exchange processes between the atmosphere and the ocean/land. The key problems of PBL physics are to determine the PBL height, the momentum, energy and matter fluxes at the surface and the mean wind and scalar profiles throughout the layer in a range of regimes from stable and neutral to convective. Until present, the PBLs typical of stormy weather were always considered as neutrally stratified. Recent works have disclosed that such PBLs are in fact very strongly affected by the static stability of the free atmosphere and must be treated as factually stable (we call this type of the PBL "conventionally neutral" in contract to the "truly neutral" PBLs developed against the neutrally stratified free flow. It is common knowledge that basic features of PBLs exhibit a noticeable dependence on the free-flow static stability and baroclinicity. However, the concern of the traditional theory of neural and stable PBLs was almost without exception the barotropic nocturnal PBL, which develops at mid latitudes during a few hours in the night, on the background of a neutral or slightly stable residual layer. The latter separates this type of the PBL from the free atmosphere. It is not surprising that the nature of turbulence in such regimes is basically local and does not depend on the properties of the free atmosphere. Alternatively, long-lived neutral (in fact only conditionally neutral or stable PBLs, which have much more time to grow up, are placed immediately below the stably stratified free flow. Under these conditions, the turbulent transports of momentum and scalars even in the surface layer - far away from the PBL outer boundary - depend on the free-flow Brunt-Väisälä frequency, N. Furthermore, integral measures of the long-lived PBLs (their depths and the resistance law functions depend on N and also on the baroclinic shear, S. In the traditional PBL models both non-local parameters N and S

  2. Atmospheric boundary layers in storms: advanced theory and modelling applications

    Science.gov (United States)

    Zilitinkevich, S. S.; Esau, I. N.; Baklanov, A.

    2005-03-01

    Turbulent planetary boundary layers (PBLs) control the exchange processes between the atmosphere and the ocean/land. The key problems of PBL physics are to determine the PBL height, the momentum, energy and matter fluxes at the surface and the mean wind and scalar profiles throughout the layer in a range of regimes from stable and neutral to convective. Until present, the PBLs typical of stormy weather were always considered as neutrally stratified. Recent works have disclosed that such PBLs are in fact very strongly affected by the static stability of the free atmosphere and must be treated as factually stable (we call this type of the PBL "conventionally neutral" in contract to the "truly neutral" PBLs developed against the neutrally stratified free flow). It is common knowledge that basic features of PBLs exhibit a noticeable dependence on the free-flow static stability and baroclinicity. However, the concern of the traditional theory of neural and stable PBLs was almost without exception the barotropic nocturnal PBL, which develops at mid latitudes during a few hours in the night, on the background of a neutral or slightly stable residual layer. The latter separates this type of the PBL from the free atmosphere. It is not surprising that the nature of turbulence in such regimes is basically local and does not depend on the properties of the free atmosphere. Alternatively, long-lived neutral (in fact only conditionally neutral) or stable PBLs, which have much more time to grow up, are placed immediately below the stably stratified free flow. Under these conditions, the turbulent transports of momentum and scalars even in the surface layer - far away from the PBL outer boundary - depend on the free-flow Brunt-Väisälä frequency, N. Furthermore, integral measures of the long-lived PBLs (their depths and the resistance law functions) depend on N and also on the baroclinic shear, S. In the traditional PBL models both non-local parameters N and S were overlooked

  3. Nonclassical models of the theory of plates and shells

    Science.gov (United States)

    Annin, B. D.; Volchkov, Yu. M.

    2016-09-01

    Publications dealing with the study of methods of reducing a three-dimensional problem of the elasticity theory to a two-dimensional problem of the theory of plates and shells are reviewed. Two approaches are considered: the use of kinematic and force hypotheses and expansion of solutions of the three-dimensional elasticity theory in terms of the complete system of functions. Papers where a three-dimensional problem is reduced to a two-dimensional problem with the use of several approximations of each sought function (stresses and displacements) by segments of Legendre polynomials are also reviewed.

  4. Modelling ADHD: A review of ADHD theories through their predictions for computational models of decision-making and reinforcement learning.

    Science.gov (United States)

    Ziegler, Sigurd; Pedersen, Mads L; Mowinckel, Athanasia M; Biele, Guido

    2016-12-01

    Attention deficit hyperactivity disorder (ADHD) is characterized by altered decision-making (DM) and reinforcement learning (RL), for which competing theories propose alternative explanations. Computational modelling contributes to understanding DM and RL by integrating behavioural and neurobiological findings, and could elucidate pathogenic mechanisms behind ADHD. This review of neurobiological theories of ADHD describes predictions for the effect of ADHD on DM and RL as described by the drift-diffusion model of DM (DDM) and a basic RL model. Empirical studies employing these models are also reviewed. While theories often agree on how ADHD should be reflected in model parameters, each theory implies a unique combination of predictions. Empirical studies agree with the theories' assumptions of a lowered DDM drift rate in ADHD, while findings are less conclusive for boundary separation. The few studies employing RL models support a lower choice sensitivity in ADHD, but not an altered learning rate. The discussion outlines research areas for further theoretical refinement in the ADHD field.

  5. Collective learning modeling based on the kinetic theory of active particles

    Science.gov (United States)

    Burini, D.; De Lillo, S.; Gibelli, L.

    2016-03-01

    This paper proposes a systems approach to the theory of perception and learning in populations composed of many living entities. Starting from a phenomenological description of these processes, a mathematical structure is derived which is deemed to incorporate their complexity features. The modeling is based on a generalization of kinetic theory methods where interactions are described by theoretical tools of game theory. As an application, the proposed approach is used to model the learning processes that take place in a classroom.

  6. Exact maps in density functional theory for lattice models

    Science.gov (United States)

    Dimitrov, Tanja; Appel, Heiko; Fuks, Johanna I.; Rubio, Angel

    2016-08-01

    In the present work, we employ exact diagonalization for model systems on a real-space lattice to explicitly construct the exact density-to-potential and graphically illustrate the complete exact density-to-wavefunction map that underly the Hohenberg-Kohn theorem in density functional theory. Having the explicit wavefunction-to-density map at hand, we are able to construct arbitrary observables as functionals of the ground-state density. We analyze the density-to-potential map as the distance between the fragments of a system increases and the correlation in the system grows. We observe a feature that gradually develops in the density-to-potential map as well as in the density-to-wavefunction map. This feature is inherited by arbitrary expectation values as functional of the ground-state density. We explicitly show the excited-state energies, the excited-state densities, and the correlation entropy as functionals of the ground-state density. All of them show this exact feature that sharpens as the coupling of the fragments decreases and the correlation grows. We denominate this feature as intra-system steepening and discuss how it relates to the well-known inter-system derivative discontinuity. The inter-system derivative discontinuity is an exact concept for coupled subsystems with degenerate ground state. However, the coupling between subsystems as in charge transfer processes can lift the degeneracy. An important conclusion is that for such systems with a near-degenerate ground state, the corresponding cut along the particle number N of the exact density functionals is differentiable with a well-defined gradient near integer particle number.

  7. Supersymmetry and string theory beyond the standard model

    CERN Document Server

    Dine, Michael

    2015-01-01

    The past decade has witnessed dramatic developments in the fields of experimental and theoretical particle physics and cosmology. This fully updated second edition is a comprehensive introduction to these recent developments and brings this self-contained textbook right up to date. Brand new material for this edition includes the groundbreaking Higgs discovery, results of the WMAP and Planck experiments. Extensive discussion of theories of dynamical electroweak symmetry breaking and a new chapter on the landscape, as well as a completely rewritten coda on future directions gives readers a modern perspective on this developing field. A focus on three principle areas: supersymmetry, string theory, and astrophysics and cosmology provide the structure for this book which will be of great interest to graduates and researchers in the fields of particle theory, string theory, astrophysics and cosmology. The book contains several problems, and password-protected solutions will be available to lecturers at www.cambrid...

  8. A model of theory-practice relations in mathematics teacher education

    DEFF Research Database (Denmark)

    Østergaard, Kaj

    2015-01-01

    The paper presents and discusses an ATD based (Chevallard, 2012) model of theory-practice relations in mathematics teacher education. The notions of didactic transposition and praxeology are combined and concretized in order to form a comprehensive model for analysing the theory-practice problema...

  9. Cybernetically sound organizational structures II: Relating de Sitter's design theory to Beer's viable system model

    NARCIS (Netherlands)

    Achterbergh, J.M.I.M.; Vriens, D.J.

    2011-01-01

    - Purpose – The purpose of this paper is to show how the viable system model (VSM) and de Sitter's design theory can complement each other in the context of the diagnosis and design of viable organizations. - Design/methodology/approach – Key concepts from Beer's model and de Sitter's design theory

  10. Design of Learning Model of Logic and Algorithms Based on APOS Theory

    Science.gov (United States)

    Hartati, Sulis Janu

    2014-01-01

    This research questions were "how do the characteristics of learning model of logic & algorithm according to APOS theory" and "whether or not these learning model can improve students learning outcomes". This research was conducted by exploration, and quantitative approach. Exploration used in constructing theory about the…

  11. Hopf Algebra Structure of a Model Quantum Field Theory

    CERN Document Server

    Solomon, A I; Blasiak, P; Horzela, A; Penson, K A

    2006-01-01

    Recent elegant work on the structure of Perturbative Quantum Field Theory (PQFT) has revealed an astonishing interplay between analysis(Riemann Zeta functions), topology (Knot theory), combinatorial graph theory (Feynman Diagrams) and algebra (Hopf structure). The difficulty inherent in the complexities of a fully-fledged field theory such as PQFT means that the essential beauty of the relationships between these areas can be somewhat obscured. Our intention is to display some, although not all, of these structures in the context of a simple zero-dimensional field theory; i.e. a quantum theory of non-commuting operators which do not depend on spacetime. The combinatorial properties of these boson creation and annihilation operators, which is our chosen example, may be described by graphs, analogous to the Feynman diagrams of PQFT, which we show possess a Hopf algebra structure. Our approach is based on the partition function for a boson gas. In a subsequent note in these Proceedings we sketch the relationship...

  12. Short-Range Correlation Models in Electronic Structure Theory

    Science.gov (United States)

    Goldey, Matthew Bryant

    fraction of MP2/CBS computational cost. Second, attenuated MP2 is developed within the larger aug-cc-pVTZ (aTZ) basis set for inter- and intramolecular non-bonded interactions. A single attenuation parameter is optimized on the S66 database of 66 intermolecular interactions, leading to a very large RMS error reduction by a factor of greater than 5 relative to standard MP2/aTZ. Attenuation introduces an error of opposite sign to basis set superposition error (BSSE) and overestimation of dispersion interactions in finite basis MP2. A variety of tests including the S22 set, conformer energies of peptides, alkanes, sugars, sulfate-water clusters, and the coronene dimer establish the transferability of the MP2(terfc, aTZ) model to other inter and intra-molecular interactions. Direct comparisons against attenuation in the smaller aug-cc-pVDZ basis shows that MP2(terfc, aTZ) often significantly outperforms MP2(terfc, aDZ), although at higher computational cost. MP2(terfc, aDZ) and MP2(terfc, aTZ) often outperform MP2 at the complete basis set limit. Comparison of the two attenuated MP2 models against each other and against attenuation using non-augmented basis sets gives insight into the error cancellation responsible for their remarkable success. Third, I present an improved algorithm for single-node multi-threaded computation of the correlation energy using resolution of the identity second-order Moller-Plesset perturbation theory (RI-MP2). This algorithm is based on shared memory parallelization of the rate-limiting steps and an overall reduction in the number of disk reads. The requisite fifth-order computation in RI-MP2 calculations is efficiently parallelized within this algorithm, with improvements in overall parallel efficiency as the system size increases. Fourth-order steps are also parallelized. As an application, I present energies and timings for several large, noncovalently interacting systems with this algorithm, and demonstrate that the RI-MP2 cost is still

  13. Accuracies of the empirical theories of the escape probability based on Eigen model and Braun model compared with the exact extension of Onsager theory.

    Science.gov (United States)

    Wojcik, Mariusz; Tachiya, M

    2009-03-14

    This paper deals with the exact extension of the original Onsager theory of the escape probability to the case of finite recombination rate at nonzero reaction radius. The empirical theories based on the Eigen model and the Braun model, which are applicable in the absence and presence of an external electric field, respectively, are based on a wrong assumption that both recombination and separation processes in geminate recombination follow exponential kinetics. The accuracies of the empirical theories are examined against the exact extension of the Onsager theory. The Eigen model gives the escape probability in the absence of an electric field, which is different by a factor of 3 from the exact one. We have shown that this difference can be removed by operationally redefining the volume occupied by the dissociating partner before dissociation, which appears in the Eigen model as a parameter. The Braun model gives the escape probability in the presence of an electric field, which is significantly different from the exact one over the whole range of electric fields. Appropriate modification of the original Braun model removes the discrepancy at zero or low electric fields, but it does not affect the discrepancy at high electric fields. In all the above theories it is assumed that recombination takes place only at the reaction radius. The escape probability in the case when recombination takes place over a range of distances is also calculated and compared with that in the case of recombination only at the reaction radius.

  14. An anthology of theories and models of design philosophy, approaches and empirical explorations

    CERN Document Server

    Blessing, Lucienne

    2014-01-01

    While investigations into both theories and models has remained a major strand of engineering design research, current literature sorely lacks a reference book that provides a comprehensive and up-to-date anthology of theories and models, and their philosophical and empirical underpinnings; An Anthology of Theories and Models of Design fills this gap. The text collects the expert views of an international authorship, covering: ·         significant theories in engineering design, including CK theory, domain theory, and the theory of technical systems; ·         current models of design, from a function behavior structure model to an integrated model; ·         important empirical research findings from studies into design; and ·         philosophical underpinnings of design itself. For educators and researchers in engineering design, An Anthology of Theories and Models of Design gives access to in-depth coverage of theoretical and empirical developments in this area; for pr...

  15. An NCME Instructional Module on Item-Fit Statistics for Item Response Theory Models

    Science.gov (United States)

    Ames, Allison J.; Penfield, Randall D.

    2015-01-01

    Drawing valid inferences from item response theory (IRT) models is contingent upon a good fit of the data to the model. Violations of model-data fit have numerous consequences, limiting the usefulness and applicability of the model. This instructional module provides an overview of methods used for evaluating the fit of IRT models. Upon completing…

  16. Two topics in nonperturbative lattice field theories: The U(1) quantum link model and perfect actions for scalar theories

    Science.gov (United States)

    Tsapalis, Antonios S.

    This thesis deals with two topics in lattice field theories. In the first part we discuss aspects of renormalization group flow and non-perturbative improvement of actions for scalar theories regularized on a lattice. We construct a perfect action, an action which is free of lattice artifacts, for a given theory. It is shown how a good approximation to the perfect action-referred to as classically perfect-can be constructed based on a well-defined blocking scheme for the O(3) non-linear σ-model. We study the O(N) non- linear σ-model in the large-N limit and derive analytically its perfect action. This action is applied to the O(3) model on a square lattice. The Wolff cluster algorithm is used to simulate numerically the system. We perform scaling tests and discuss the scaling properties of the large- N inspired perfect action as opposed to the standard and the classically perfect action. In the second part we present a new formulation for a quantum field theory with Abelian gauge symmetry. A Hamiltonian is constructed on a four-dimensional Euclidean space-time lattice which is invariant under local transformations. The model is formulated as a 5- dimensional path integral of discrete variables. We argue that dimensional reduction will allow us to study the behavior of the standard compact U(1) gauge theory in 4-d. Based on the idea of the loop- cluster algorithm for quantum spins, we present the construction of a flux-cluster algorithm for the U(1) quantum link model for the spin-1/2 quantization of the electric flux. It is shown how improved estimators for Wilson loop expectation values can be defined. This is important because the Wilson loops are traditionally used to identify confining and Coulomb phases in gauge theories. Our study indicates that the spin-1/2 U(1) quantum link model is strongly coupled for all bare coupling values we examined. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

  17. A matrix model for heterotic Spin(32)/Z sub 2 and type I string theory

    CERN Document Server

    Krogh, M

    1999-01-01

    We consider heterotic string theories in the DLCQ. We derive that the matrix model of the Spin(32)/Z sub 2 heterotic theory is the theory living on N D-strings in type I wound on a circle with no Spin(32)/Z sub 2 Wilson line on the circle. This is an O(N) gauge theory. We rederive the matrix model for the E sub 8 xE sub 8 heterotic string theory, explicitly taking care of the Wilson line around the lightlike circle. The result is the same theory as for Spin(32)/Z sub 2 except that now there is a Wilson line on the circle. We also see that the integer N labeling the sector of the O(N) matrix model is not just the momentum around the lightlike circle, but a shifted momentum depending on the Wilson line. We discuss the aspect of level matching, GSO projections and why, from the point of view of matrix theory the E sub 8 xE sub 8 theory, and not the Spin(32)/Z sub 2 , develops an 11th dimension for strong coupling. Furthermore a matrix theory for type I is derived. This is again the O(N) theory living on the D-st...

  18. Calculation of Surface Tensions of Polar Mixtures with a Simplified Gradient Theory Model

    DEFF Research Database (Denmark)

    Zuo, You-Xiang; Stenby, Erling Halfdan

    1996-01-01

    Key Words: Thermodynamics, Simplified Gradient Theory, Surface Tension, Equation of state, Influence Parameter.In this work, assuming that the number densities of each component in a mixture across the interface between the coexisting vapor and liquid phases are linearly distributed, we developed...... a simplified gradient theory (SGT) model for computing surface tensions. With this model, it is not required to solve the time-consuming density profile equations of the gradient theory model. The SRK EOS was applied to calculate the properties of the homogeneous fluid. First, the SGT model was used to predict...

  19. Deriving Veneziano Model in a Novel String Field Theory Solving String Theory by Liberating Right and Left Movers

    CERN Document Server

    Nielsen, Holger B

    2014-01-01

    Bosonic string theory with the possibility for an arbitrary number of strings - i.e. a string ?eld theory - is formulated by a Hilbert space (a Fock space), which is just that for massless noninteracting scalars. We earlier presented this novel type of string ?eld theory, but now we show that it leads to scattering just given by the Veneziano model amplitude. Generalization to strings with fermion modes would presumably be rather easy. It is characteristic for our formulation /model that: 1) We have thrown away some null set of information compared to usual string ?eld theory, 2)Formulated in terms of our \\objects" (= the non-interacting scalars) there is no interaction and essentially no time development(Heisenberg picture), 3) so that the S-matrix is in our Hilbert space given as the unit matrix, S=1, and 4) the Veneziano scattering amplitude appear as the overlap between the initial and the ?nal state described in terms of the \\objects". 5) The integration in the Euler beta function making up the Veneziano...

  20. Comparison of Geant4 multiple Coulomb scattering models with theory for radiotherapy protons

    CERN Document Server

    Makarova, Anastasia; Sauerwein, Wolfgang

    2016-01-01

    Usually, Monte Carlo models are validated against experimental data. However, models of multiple Coulomb scattering (MCS) in the Gaussian approximation are exceptional in that we have theories which are probably more accurate than the experiments which have, so far, been done to test them. In problems directly sensitive to the distribution of angles leaving the target, the relevant theory is the Moliere/Fano/Hanson variant of Moliere theory. For transverse spreading of the beam in the target itself, the theory of Preston and Koehler holds. Therefore, in this paper we compare Geant4 simulations, using the Urban and Wentzel models of MCS, with theory rather than experiment, revealing trends which would otherwise be obscured by experimental scatter. For medium-energy (radiotherapy) protons, and low-Z (water-like) target materials, Wentzel appears to be better than Urban in simulating the distribution of outgoing angles. For beam spreading in the target itself, the two models are essentially equal.

  1. A Note on Dimer Models and D-brane Gauge Theories

    CERN Document Server

    Agarwal, Prarit; Sarkar, Tapobrata

    2008-01-01

    The connection between quiver gauge theories and dimer models has been well studied. It is known that the matter fields of the quiver gauge theories can be represented using the perfect matchings of the dimer model. We conjecture that the perfect matchings give information about the charge matrix of the quiver gauge theory. Further, we perform explicit computations on some aspects of partial resolutions of toric singularities using dimer models. We analyse these with graph theory techniques, using the perfect matchings of orbifolds of the form $\\BC^3/\\Gamma$, where the orbifolding group $\\Gamma$ may be noncyclic. Using these, we study the construction of the superpotential of gauge theories living on D-branes which probe these singularities, including the case where one or more adjoint fields are present upon partial resolution. Applying a combination of open and closed string techniques to dimer models, we also study some aspects of their symmetries.

  2. A modular approach for item response theory modeling with the R package flirt.

    Science.gov (United States)

    Jeon, Minjeong; Rijmen, Frank

    2016-06-01

    The new R package flirt is introduced for flexible item response theory (IRT) modeling of psychological, educational, and behavior assessment data. flirt integrates a generalized linear and nonlinear mixed modeling framework with graphical model theory. The graphical model framework allows for efficient maximum likelihood estimation. The key feature of flirt is its modular approach to facilitate convenient and flexible model specifications. Researchers can construct customized IRT models by simply selecting various modeling modules, such as parametric forms, number of dimensions, item and person covariates, person groups, link functions, etc. In this paper, we describe major features of flirt and provide examples to illustrate how flirt works in practice.

  3. Parental Acceptance-Rejection Theory and the Phylogenetic Model.

    Science.gov (United States)

    Rohner, Ronald P.

    Guided by specific theoretical and methodological points of view--the phylogenetic perspective and the universalistic approach respectively--this paper reports on a worldwide study of the antecedents and effects of parental acceptance and rejection. Parental acceptance-rejection theory postulates that rejected children throughout our species share…

  4. An Energy Model for Viewing Embodied Human Capital Theory

    Science.gov (United States)

    Kaufman, Neil A.; Geroy, Gary D.

    2007-01-01

    Human capital development is one of the emerging areas of study with regard to social science theory, practice, and research. A relatively new concept, human capital is described in terms of individual knowledge skills and experience. It is currently expressed as a function of education as well as a measure of economic activity. Little theory…

  5. Towards a Theory of University Entrepreneurship: Developing a Theoretical Model

    Science.gov (United States)

    Woollard, David

    2010-01-01

    This paper sets out to develop a robust theory in a largely atheoretical field of study. The increasing importance of entrepreneurship in delivering the "Third Mission" calls for an enhanced understanding of the university entrepreneurship phenomenon, not solely as a subject of academic interest but also to guide the work of practitioners in the…

  6. On a Unified Theory of Estimation in Linear Models

    Science.gov (United States)

    which depends on the numerical evaluation of a g-inverse of a partitioned matrix. Another is an analogue of least square theory and is called unified... least square (ULS) method. The aim of the paper is to bring out the salient features of these two methods and to point out some interesting features of

  7. An Energy Model for Viewing Embodied Human Capital Theory

    Science.gov (United States)

    Kaufman, Neil A.; Geroy, Gary D.

    2007-01-01

    Human capital development is one of the emerging areas of study with regard to social science theory, practice, and research. A relatively new concept, human capital is described in terms of individual knowledge skills and experience. It is currently expressed as a function of education as well as a measure of economic activity. Little theory…

  8. Applying circular economy innovation theory in business process modeling and analysis

    Science.gov (United States)

    Popa, V.; Popa, L.

    2017-08-01

    The overall aim of this paper is to develop a new conceptual framework for business process modeling and analysis using circular economy innovative theory as a source for business knowledge management. The last part of the paper presents an author’s proposed basic structure for a new business models applying circular economy innovation theories. For people working on new innovative business models in the field of the circular economy this paper provides new ideas for clustering their concepts.

  9. Effective-field-theory model for the fractional quantum Hall effect

    Science.gov (United States)

    Zhang, S. C.; Hansson, T. H.; Kivelson, S.

    1989-01-01

    Starting directly from the microscopic Hamiltonian, a field-theory model is derived for the fractional quantum Hall effect. By considering an approximate coarse-grained version of the same model, a Landau-Ginzburg theory similar to that of Girvin (1986) is constructed. The partition function of the model exhibits cusps as a function of density. It is shown that the collective density fluctuations are massive.

  10. Lyapunov stability in an evolutionary game theory model of the labour market

    Directory of Open Access Journals (Sweden)

    Ricardo Azevedo Araujo

    2014-01-01

    Full Text Available In this paper the existence and stability of equilibriums in an evolutionary game theory model of the labour market is studied by using the Lyapunov method. The model displays multiple equilibriums and it is shown that the Nash equilibriums of the static game are evolutionary stable equilibrium in the game theory evolutionary set up. A complete characterization of the dynamics of an evolutionary model of the labour market is provided.

  11. [Condom use among heterosexuals: a comparison of the theory of planned behavior, the health belief model and protection motivation theory].

    Science.gov (United States)

    Bakker, A B; Buunk, B P; Siero, F W

    1993-10-01

    In the Netherlands, the theory of planned behavior (Ajzen, 1991), the health belief model (Janz and Becker, 1984), and the protection-motivation theory (Rogers, 1983) were compared for predicting condom use intentions because of AIDS. The 641 respondents were given two questionnaires: one for themselves and another one for a friend, partner, or acquaintance. 514 (80%) of them returned completed forms. 60% of these (307) persons were encouraged to answer and return another questionnaire, thus the final sample consisted of 821 responses. 711 individuals (481 women aged 15-91 years and 230 men aged 15-85 years) admitted having had heterosexual intercourse. 75% had had more than one sex partner in the previous 5 years. 45% had had sex at least once with someone other than their regular partner. Multivariance analysis of variance of promiscuity and condom use revealed that men exhibited more risky sex practices than women (p .001), had more sex partners in the previous 5 years than women (p .01), had more single sexual encounters with other persons than the regular sex partner than women (p .001), and they used condoms less often than women (p .01). 119 respondents had experienced sexually transmitted diseases and 165 had taken HIV tests. The difference between men and women also showed up in terms of their ideas, perceptions, and feelings about condom use when the three theoretical models were considered (p .001). The variables used in the theory of planned behavior explained the variance in intended condom use for 36% of women and 43% of men. The health belief model explained intended condom use only for 15% of women and 32% of men, while the cost-benefit analysis explained it for 9% of women and 18% of men. The protection-motivation theory explained intended condom use variance for 32% of women and 41% of men, but not all variables were included in the model. Fear from AIDS was correlated with inquisitive behavior and with seriousness (both p .001).

  12. A Primer of Social Decision Scheme Theory: Models of Group Influence, Competitive Model-Testing, and Prospective Modeling.

    Science.gov (United States)

    Stasser

    1999-10-01

    The basic elements of social decision scheme (SDS) theory are individual preferences, group preference compositions (distinguishable distributions), patterns of group influence (decision schemes, social combination rules), and collective responses (group decisions, judgments, solutions, and the like). The theory provides a framework for addressing two fundamental questions in the study of group performance: How are individual resources combined to yield a group response (the individual-into-group problem)? What are the implications of empirical observations under one set of circumstances for other conditions where data do not exist (the sparse data problem)? Several prescriptions for how to conduct fruitful group research are contained in the SDS tradition: make precise theoretical statements, provide strong and competitive tests of theories, and interpret empirical findings in the context of robust process models. Copyright 1999 Academic Press.

  13. Applying Catastrophe Theory to an Information-Processing Model of Problem Solving in Science Education

    Science.gov (United States)

    Stamovlasis, Dimitrios; Tsaparlis, Georgios

    2012-01-01

    In this study, we test an information-processing model (IPM) of problem solving in science education, namely the working memory overload model, by applying catastrophe theory. Changes in students' achievement were modeled as discontinuities within a cusp catastrophe model, where working memory capacity was implemented as asymmetry and the degree…

  14. Applying Catastrophe Theory to an Information-Processing Model of Problem Solving in Science Education

    Science.gov (United States)

    Stamovlasis, Dimitrios; Tsaparlis, Georgios

    2012-01-01

    In this study, we test an information-processing model (IPM) of problem solving in science education, namely the working memory overload model, by applying catastrophe theory. Changes in students' achievement were modeled as discontinuities within a cusp catastrophe model, where working memory capacity was implemented as asymmetry and the degree…

  15. Spectral density of the correlation matrix of factor models: a random matrix theory approach.

    Science.gov (United States)

    Lillo, F; Mantegna, R N

    2005-07-01

    We studied the eigenvalue spectral density of the correlation matrix of factor models of multivariate time series. By making use of the random matrix theory, we analytically quantified the effect of statistical uncertainty on the spectral density due to the finiteness of the sample. We considered a broad range of models, ranging from one-factor models to hierarchical multifactor models.

  16. A new k-epsilon model consistent with Monin-Obukhov similarity theory

    DEFF Research Database (Denmark)

    van der Laan, Paul; Kelly, Mark C.; Sørensen, Niels N.

    2016-01-01

    A new k-" model is introduced that is consistent with Monin–Obukhov similarity theory (MOST). The proposed k-" model is compared with another k-" model that was developed in an attempt to maintain inlet profiles compatible with MOST. It is shown that the previous k-" model is not consistent with ...

  17. Target Rotations and Assessing the Impact of Model Violations on the Parameters of Unidimensional Item Response Theory Models

    Science.gov (United States)

    Reise, Steven; Moore, Tyler; Maydeu-Olivares, Alberto

    2011-01-01

    Reise, Cook, and Moore proposed a "comparison modeling" approach to assess the distortion in item parameter estimates when a unidimensional item response theory (IRT) model is imposed on multidimensional data. Central to their approach is the comparison of item slope parameter estimates from a unidimensional IRT model (a restricted model), with…

  18. Univariate and multivariate general linear models theory and applications with SAS

    CERN Document Server

    Kim, Kevin

    2006-01-01

    Reviewing the theory of the general linear model (GLM) using a general framework, Univariate and Multivariate General Linear Models: Theory and Applications with SAS, Second Edition presents analyses of simple and complex models, both univariate and multivariate, that employ data sets from a variety of disciplines, such as the social and behavioral sciences.With revised examples that include options available using SAS 9.0, this expanded edition divides theory from applications within each chapter. Following an overview of the GLM, the book introduces unrestricted GLMs to analyze multiple regr

  19. Anisotropic cosmological models in $f (R, T)$ theory of gravitation

    Indian Academy of Sciences (India)

    Shri Ram; Priyanka; Manish Kumar Singh

    2013-07-01

    A class of non-singular bouncing cosmological models of a general class of Bianchi models filled with perfect fluid in the framework of $f (R, T)$ gravity is presented. The model initially accelerates for a certain period of time and decelerates thereafter. The physical behaviour of the model is also studied.

  20. Perturbation theory calculations of model pair potential systems

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Jianwu [Iowa State Univ., Ames, IA (United States)

    2016-01-01

    Helmholtz free energy is one of the most important thermodynamic properties for condensed matter systems. It is closely related to other thermodynamic properties such as chemical potential and compressibility. It is also the starting point for studies of interfacial properties and phase coexistence if free energies of different phases can be obtained. In this thesis, we will use an approach based on the Weeks-Chandler-Anderson (WCA) perturbation theory to calculate the free energy of both solid and liquid phases of Lennard-Jones pair potential systems and the free energy of liquid states of Yukawa pair potentials. Our results indicate that the perturbation theory provides an accurate approach to the free energy calculations of liquid and solid phases based upon comparisons with results from molecular dynamics (MD) and Monte Carlo (MC) simulations.

  1. A model of theory-practice relations in mathematics teacher education

    DEFF Research Database (Denmark)

    Østergaard, Kaj

    2015-01-01

    The paper presents and discusses an ATD based (Chevallard, 2012) model of theory-practice relations in mathematics teacher education. The notions of didactic transposition and praxeology are combined and concretized in order to form a comprehensive model for analysing the theory-practice problema......The paper presents and discusses an ATD based (Chevallard, 2012) model of theory-practice relations in mathematics teacher education. The notions of didactic transposition and praxeology are combined and concretized in order to form a comprehensive model for analysing the theory......-practice problematique. It is illustrated how the model can be used both as a descriptive tool to analyse interactions between and interviews with student teachers and teachers and as a normative tool to design and redesign learning environments in teacher education in this case a lesson study context....

  2. Generation companies decision-making modeling by linear control theory

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez-Alcaraz, G. [Programa de Graduados e Investigacion en Ingenieria Electrica. Departamento de Ingenieria Electrica y Electronica, Instituto Tecnologico de Morelia. Av. Tecnologico 1500, Col. Lomas de Santiaguito 58120. Morelia, Mich. (Mexico); Sheble, Gerald B. [INESC Porto, Faculdade de Engenharia, Universidade do Porto, Campus da FEUP, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal)

    2010-07-15

    This paper proposes four decision-making procedures to be employed by electric generating companies as part of their bidding strategies when competing in an oligopolistic market: naive, forward, adaptive, and moving average expectations. Decision-making is formulated in a dynamic framework by using linear control theory. The results reveal that interactions among all GENCOs affect market dynamics. Several numerical examples are reported, and conclusions are presented. (author)

  3. Modeling second language change using skill retention theory

    OpenAIRE

    Shearer, Samuel R.

    2013-01-01

    Approved for public release; distribution is unlimited Loss of foreign language proficiency is a major concern for the Department of Defense (DoD). Despite significant expenditures to develop and sustain foreign language skills in the armed forces, the DoD has not been able to create a sufficient pool of qualified linguists. Many theories and hypotheses about the learning of foreign languages are not based on cognitive processes and lack the ability to explain how and why foreign language ...

  4. Buckled graphene: A model study based on density functional theory

    KAUST Repository

    Khan, Mohammad A.

    2010-09-01

    We make use of ab initio calculations within density functional theory to investigate the influence of buckling on the electronic structure of single layer graphene. Our systematic study addresses a wide range of bond length and bond angle variations in order to obtain insights into the energy scale associated with the formation of ripples in a graphene sheet. © 2010 Elsevier B.V. All rights reserved.

  5. Models, Mechanisms and Moderators Dissociating Empathy and Theory of Mind.

    Science.gov (United States)

    Kanske, Philipp; Böckler, Anne; Singer, Tania

    Most instances of social interaction provide a wealth of information about the states of other people, be it sensations, feelings, thoughts, or convictions. How we represent these states has been a major question in social neuroscience, leading to the identification of two routes to understanding others: an affective route for the direct sharing of others' emotions (empathy) that involves, among others, anterior insula and middle anterior cingulate cortex and a cognitive route for representing and reasoning about others' states (Theory of Mind) that entails, among others, ventral temporoparietal junction and anterior and posterior midline regions. Additionally, research has revealed a number of situational and personal factors that shape the functioning of empathy and Theory of Mind. Concerning situational modulators, it has been shown, for instance, that ingroup membership enhances empathic responding and that Theory of Mind performance seems to be susceptible to stress. Personal modulators include psychopathological conditions, for which alterations in empathy and mentalizing have consistently been demonstrated; people on the autism spectrum, for instance, are impaired specifically in mentalizing, while spontaneous empathic responding seems selectively reduced in psychopathy. Given the multifaceted evidence for separability of the two routes, current research endeavors aiming at fostering interpersonal cooperation explore the differential malleability of affective and cognitive understanding of others.

  6. Anisotropic Cosmological Model in Modified Brans--Dicke Theory

    CERN Document Server

    Rasouli, S M M; Sepangi, Hamid R

    2011-01-01

    It has been shown that four dimensional Brans-Dicke theory with effective matter field and self interacting potential can be achieved from vacuum 5D BD field equations, where we refer to as modified Brans-Dicke theory (MBDT). We investigate a generalized Bianchi type I anisotropic cosmology in 5D BD theory, and by employing obtained formalism, we derive induced-matter on any 4D hypersurface in context of the MBDT. We illustrate that if the usual spatial scale factors are functions of time while scale factor of extra dimension is constant, and scalar field depends on time and fifth coordinate, then in general, one will encounter inconsistencies in field equations. Then, we assume the scale factors and scalar field depend on time and extra coordinate as separated variables in power law forms. Hence, we find a few classes of solutions in 5D spacetime through which, we probe the one which leads to a generalized Kasner relations among Kasner parameters. The induced scalar potential is found to be in power law or i...

  7. Causal Agency Theory: Reconceptualizing a Functional Model of Self-Determination

    Science.gov (United States)

    Shogren, Karrie A.; Wehmeyer, Michael L.; Palmer, Susan B.; Forber-Pratt, Anjali J.; Little, Todd J.; Lopez, Shane

    2015-01-01

    This paper introduces Causal Agency Theory, an extension of the functional model of self-determination. Causal Agency Theory addresses the need for interventions and assessments pertaining to selfdetermination for all students and incorporates the significant advances in understanding of disability and in the field of positive psychology since the…

  8. Causal Agency Theory: Reconceptualizing a Functional Model of Self-Determination

    Science.gov (United States)

    Shogren, Karrie A.; Wehmeyer, Michael L.; Palmer, Susan B.; Forber-Pratt, Anjali J.; Little, Todd J.; Lopez, Shane

    2015-01-01

    This paper introduces Causal Agency Theory, an extension of the functional model of self-determination. Causal Agency Theory addresses the need for interventions and assessments pertaining to selfdetermination for all students and incorporates the significant advances in understanding of disability and in the field of positive psychology since the…

  9. A Facet Theory Model for Integrating Contextual and Personal Experiences of International Students

    Science.gov (United States)

    Hackett, Paul M. W.

    2014-01-01

    The purpose of this article is to use a facet theory research approach to provide a clear, coherent, and integrated model of international students' experiences based upon the findings of psychological research into students when studying abroad. In research that employs a facet theory approach events are classified in terms of their constituent…

  10. Implications of Bandura's Observational Learning Theory for a Competency Based Teacher Education Model.

    Science.gov (United States)

    Hartjen, Raymond H.

    Albert Bandura of Stanford University has proposed four component processes to his theory of observational learning: a) attention, b) retention, c) motor reproduction, and d) reinforcement and motivation. This study represents one phase of an effort to relate modeling and observational learning theory to teacher training. The problem of this study…

  11. Nonlinear observer design for a nonlinear string/cable FEM model using contraction theory

    DEFF Research Database (Denmark)

    Turkyilmaz, Yilmaz; Jouffroy, Jerome; Egeland, Olav

    Contraction theory is a recently developed nonlinear analysis tool which may be useful for solving a variety of nonlinear control problems. In this paper, using Contraction theory, a nonlinear observer is designed for a general nonlinear cable/string FEM (Finite Element Method) model. The cable...

  12. Experimental Aeroelastic Models Design and Wind Tunnel Testing for Correlation with New Theory

    Directory of Open Access Journals (Sweden)

    2016-04-01

    Full Text Available Several examples of experimental model designs, wind tunnel tests and correlation with new theory are presented in this paper. The goal is not only to evaluate a new theory, new computational method or new aeroelastic phonomenon, but also to provide new insights into nonlinear aeroelastic phenomena, flutter, limit cycle oscillation (LCO and gust response.

  13. Nonlinear observer design for a nonlinear string/cable FEM model using contraction theory

    DEFF Research Database (Denmark)

    Turkyilmaz, Yilmaz; Jouffroy, Jerome; Egeland, Olav

    Contraction theory is a recently developed nonlinear analysis tool which may be useful for solving a variety of nonlinear control problems. In this paper, using Contraction theory, a nonlinear observer is designed for a general nonlinear cable/string FEM (Finite Element Method) model. The cable...

  14. Using Molecular Modeling in Teaching Group Theory Analysis of the Infrared Spectra of Organometallic Compounds

    Science.gov (United States)

    Wang, Lihua

    2012-01-01

    A new method is introduced for teaching group theory analysis of the infrared spectra of organometallic compounds using molecular modeling. The main focus of this method is to enhance student understanding of the symmetry properties of vibrational modes and of the group theory analysis of infrared (IR) spectra by using visual aids provided by…

  15. Using Molecular Modeling in Teaching Group Theory Analysis of the Infrared Spectra of Organometallic Compounds

    Science.gov (United States)

    Wang, Lihua

    2012-01-01

    A new method is introduced for teaching group theory analysis of the infrared spectra of organometallic compounds using molecular modeling. The main focus of this method is to enhance student understanding of the symmetry properties of vibrational modes and of the group theory analysis of infrared (IR) spectra by using visual aids provided by…

  16. Evolution of species from Darwin theory: A simple model

    Science.gov (United States)

    Moret, M. A.; Pereira, H. B. B.; Monteiro, S. L.; Galeão, A. C.

    2012-04-01

    Evolution of species is a complex phenomenon. Some theoretical models take into account evolution of species, like the Bak-Sneppen model that obtain punctuated equilibrium from self-organized criticality and the Penna model for biological aging that consists in a bit-string model subjected to aging, reproduction and death. In this work we propose a simple model to study different scenarios used to simulate the evolution of species. This model is based on Darwin's ideas of evolution. The present findings show that punctuated equilibria and stasis seem to be obtained directly from the mutation, selection of parents and the genetic crossover, and are very close to the fossil data analysis.

  17. Consumption-based macroeconomic models of asset pricing theory

    Directory of Open Access Journals (Sweden)

    Đorđević Marija

    2016-01-01

    Full Text Available The family of consumptionbased asset pricing models yields a stochastic discount factor proportional to the marginal rate of intertemporal substitution of consumption. In examining the empirical performance of this class of models, several puzzles are discovered. In this literature review we present the canonical model, the corresponding empirical tests, and different extensions to this model that propose a resolution of these puzzles.

  18. Theories and control models and motor learning: clinical applications in neuro-rehabilitation.

    Science.gov (United States)

    Cano-de-la-Cuerda, R; Molero-Sánchez, A; Carratalá-Tejada, M; Alguacil-Diego, I M; Molina-Rueda, F; Miangolarra-Page, J C; Torricelli, D

    2015-01-01

    In recent decades there has been a special interest in theories that could explain the regulation of motor control, and their applications. These theories are often based on models of brain function, philosophically reflecting different criteria on how movement is controlled by the brain, each being emphasised in different neural components of the movement. The concept of motor learning, regarded as the set of internal processes associated with practice and experience that produce relatively permanent changes in the ability to produce motor activities through a specific skill, is also relevant in the context of neuroscience. Thus, both motor control and learning are seen as key fields of study for health professionals in the field of neuro-rehabilitation. The major theories of motor control are described, which include, motor programming theory, systems theory, the theory of dynamic action, and the theory of parallel distributed processing, as well as the factors that influence motor learning and its applications in neuro-rehabilitation. At present there is no consensus on which theory or model defines the regulations to explain motor control. Theories of motor learning should be the basis for motor rehabilitation. The new research should apply the knowledge generated in the fields of control and motor learning in neuro-rehabilitation. Copyright © 2011 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  19. Harmony Theory: Problem Solving, Parallel Cognitive Models, and Thermal Physics.

    Science.gov (United States)

    Smolensky, Paul; Riley, Mary S.

    This document consists of three papers. The first, "A Parallel Model of (Sequential) Problem Solving," describes a parallel model designed to solve a class of relatively simple problems from elementary physics and discusses implications for models of problem-solving in general. It is shown that one of the most salient features of problem…

  20. Security giving in surrogacy motherhood process as a caring model for commissioning mothers: A theory synthesis.

    Science.gov (United States)

    Zandi, Mitra; Vanaki, Zohreh; Shiva, Marziyeh; Mohammadi, Eesa; Bagheri-Lankarani, Narges

    2016-07-01

    Despite the increasing use of surrogacy, there are no caring theories/models that serve as the basis for nursing care to surrogacy commissioning mothers. This study has designed a model for caring of surrogacy commissioning mothers in 2013. The theory synthesis of Walker and Avant's strategies of theory construction (2011) was used to design a caring model/theory. The theory synthesis includes three stages: (i) selection of focal concept (the concept of "security giving in motherhood" was selected); (ii) review of studies in order to identify factors related to focal concept relevant studies (42 articles and 13 books) were reviewed, statements and concepts related to focal concept were then extracted and classified, and their relations were specified; and (iii) organization of concepts and statements within a relevant general and effective manifestation of the phenomenon under study which led to developing of a model. In this caring model/theory, entitled "security giving in surrogacy motherhood", nurses roles were conceptualized within the conceptual framework that includes three main roles: (i) coordination; (ii) participation; and (iii) security giving (physical, emotional, and legal support; empowerment; presence; relationship management between both parties and advocacy). Training surrogacy specialist nurses and establishment of surrogacy care centers are important factors for implementation of the model. This model could help to provided better caring for surrogacy clients, especially for commissioning mothers. © 2016 Japan Academy of Nursing Science.