Sierra, C. A.; Mueller, M.
2013-12-01
Recent work have highlighted the importance of nonlinear interactions in representing the decomposition of soil organic matter (SOM). It is unclear however how to integrate these concepts into larger biogeochemical models or into a more general mathematical description of the decomposition process. Here we present a mathematical framework that generalizes both previous decomposition models and recent ideas about nonlinear microbial interactions. The framework is based on a set of four basic principles: 1) mass balance, 2) heterogeneity in the decomposability of SOM, 3) transformations in the decomposability of SOM over time, 4) energy limitation of decomposers. This framework generalizes a large majority of SOM decomposition models proposed to date. We illustrate the application of this framework to the development of a continuous model that includes the ideas in the Dual Arrhenius Michaelis-Menten Model (DAMM) for explicitly representing temperature-moisture limitations of enzyme activity in the decomposition of heterogenous substrates.
The Internet accessible mathematical computation framework
Institute of Scientific and Technical Information of China (English)
Paul S. Wang; Simon Gray; Norbert Kajler; Dongdai Lin; Weidong Liao; Xiao Zou
2004-01-01
The Internet Accessible Mathematical Computation (IAMC) framework aims to make it easy to supply mathematical computing powers over the Internet/Web. The protocol-based IAMC framework enables developers to create interoperable clients and servers easily and independently. Presented are conceptual and experimental work on the IAMC framework architecture and major components: the Mathematical Computation Protocol (MCP), a client prototype (Dragonfly), a server prototype (Starfish), a mathematical encoding converter (XMEC), and an open mathematical compute engine interface (OMEI).
Mathematical Articles for the general public
DEFF Research Database (Denmark)
Hansen, Vagn Lundsgaard
2003-01-01
Report on an article competition for mathematical articles addressing the general public arranged by the European Mathematical Society.......Report on an article competition for mathematical articles addressing the general public arranged by the European Mathematical Society....
Mathematical Articles for the general public
DEFF Research Database (Denmark)
Hansen, Vagn Lundsgaard
2003-01-01
Report on an article competition for mathematical articles addressing the general public arranged by the European Mathematical Society.......Report on an article competition for mathematical articles addressing the general public arranged by the European Mathematical Society....
A Mathematical Framework for Statistical Decision Confidence.
Hangya, Balázs; Sanders, Joshua I; Kepecs, Adam
2016-09-01
Decision confidence is a forecast about the probability that a decision will be correct. From a statistical perspective, decision confidence can be defined as the Bayesian posterior probability that the chosen option is correct based on the evidence contributing to it. Here, we used this formal definition as a starting point to develop a normative statistical framework for decision confidence. Our goal was to make general predictions that do not depend on the structure of the noise or a specific algorithm for estimating confidence. We analytically proved several interrelations between statistical decision confidence and observable decision measures, such as evidence discriminability, choice, and accuracy. These interrelationships specify necessary signatures of decision confidence in terms of externally quantifiable variables that can be empirically tested. Our results lay the foundations for a mathematically rigorous treatment of decision confidence that can lead to a common framework for understanding confidence across different research domains, from human and animal behavior to neural representations.
A Framework of Mathematics Inductive Reasoning
Christou, Constantinos; Papageorgiou, Eleni
2007-01-01
Based on a synthesis of the literature in inductive reasoning, a framework for prescribing and assessing mathematics inductive reasoning of primary school students was formulated and validated. The major constructs incorporated in this framework were students' cognitive abilities of finding similarities and/or dissimilarities among attributes and…
Generalized Software Security Framework
Directory of Open Access Journals (Sweden)
Smriti Jain
2011-01-01
Full Text Available Security of information has become a major concern in today's digitized world. As a result, effective techniques to secure information are required. The most effective way is to incorporate security in the development process itself thereby resulting into secured product. In this paper, we propose a framework that enables security to be included in the software development process. The framework consists of three layers namely; control layer, aspect layer and development layer. The control layer illustrates the managerial control of the entire software development process with the help of governance whereas aspect layer recognizes the security mechanisms that can be incorporated during the software development to identify the various security features. The development layer helps to integrate the various security aspects as well as the controls identified in the above layers during the development process. The layers are further verified by a survey amongst the IT professionals. The professionals concluded that the developed framework is easy to use due to its layered architecture and, can be customized for various types of softwares.
Anku, Sitsofe E.
1997-09-01
Using the reform documents of the National Council of Teachers of Mathematics (NCTM) (NCTM, 1989, 1991, 1995), a theory-based multi-dimensional assessment framework (the "SEA" framework) which should help expand the scope of assessment in mathematics is proposed. This framework uses a context based on mathematical reasoning and has components that comprise mathematical concepts, mathematical procedures, mathematical communication, mathematical problem solving, and mathematical disposition.
Mathematical Definitions of Operators for Cartographic Generalization
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
This paper puts forword 11 cartographic generalization operator models and introduces their mathematical definitions,and thus a precise mathematical form and quantitative description has been given to these formerly limited qualitative concepts.The meaning of mathematical definition of operators for cartographic generalization and the application prospect in computer-aided cartography (CAC) is stated.
Molecular Phylogenetics: Mathematical Framework and Unsolved Problems
Xia, Xuhua
Phylogenetic relationship is essential in dating evolutionary events, reconstructing ancestral genes, predicting sites that are important to natural selection, and, ultimately, understanding genomic evolution. Three categories of phylogenetic methods are currently used: the distance-based, the maximum parsimony, and the maximum likelihood method. Here, I present the mathematical framework of these methods and their rationales, provide computational details for each of them, illustrate analytically and numerically the potential biases inherent in these methods, and outline computational challenges and unresolved problems. This is followed by a brief discussion of the Bayesian approach that has been recently used in molecular phylogenetics.
A Framework for Examining Teachers' Noticing of Mathematical Cognitive Technologies
Smith, Ryan; Shin, Dongjo; Kim, Somin
2017-01-01
In this paper, we propose the mathematical cognitive technology noticing framework for examining how mathematics teachers evaluate, select, and modify mathematical cognitive technology to use in their classrooms. Our framework is based on studies of professional and curricular noticing and data collected in a study that explored how secondary…
Mathematics Framework for the 2005 National Assessment of Educational Progress
Howe, Roger; Scheaffer, Richard; Lindquist, Mary; Philip, Frank; Halbrook, Arthur
2004-01-01
This document contains the framework and a set of recommendations for the 2005 NAEP mathematics assessment. It includes descriptions of the mathematical content of the test, the types of test questions, and recommendations for administration of the test. In broad terms, this framework attempts to answer the question: What mathematics should be…
General systems theory mathematical foundations
Mesarovic, Mihajlo D
1975-01-01
In this book, we study theoretical and practical aspects of computing methods for mathematical modelling of nonlinear systems. A number of computing techniques are considered, such as methods of operator approximation with any given accuracy; operator interpolation techniques including a non-Lagrange interpolation; methods of system representation subject to constraints associated with concepts of causality, memory and stationarity; methods of system representation with an accuracy that is the best within a given class of models; methods of covariance matrix estimation;methods for low-rank mat
A Generalized DRM Architectural Framework
Directory of Open Access Journals (Sweden)
PATRICIU, V. V.
2011-02-01
Full Text Available Online digital goods distribution environment lead to the need for a system to protect digital intellectual property. Digital Rights Management (DRM is the system born to protect and control distribution and use of those digital assets. The present paper is a review of the current state of DRM, focusing on architectural design, security technologies, and important DRM deployments. The paper primarily synthesizes DRM architectures within a general framework. We also present DRM ecosystem as providing a better understanding of what is currently happening to content rights management from a technological point of view. This paper includes conclusions of several DRM initiative studies, related to rights management systems with the purpose of identifying and describing the most significant DRM architectural models. The basic functions and processes of the DRM solutions are identified.
Depth of Teachers' Knowledge: Frameworks for Teachers' Knowledge of Mathematics
Holmes, Vicki-Lynn
2012-01-01
This article describes seven teacher knowledge frameworks and relates these frameworks to the teaching and assessment of elementary teacher's mathematics knowledge. The frameworks classify teachers' knowledge and provide a vocabulary and common language through which knowledge can be discussed and assessed. These frameworks are categorized into…
A Reconceptualized Framework for "Opportunity to Learn" in School Mathematics
Walkowiak, Temple A.; Pinter, Holly H.; Berry, Robert Q.
2017-01-01
We present a reconceptualized framework for opportunity to learn (OTL) in school mathematics that builds on previous conceptualizations of OTL and includes features related to both quantity (i.e., time) and quality. Our framework draws on existing literature and on our own observational research of mathematics teaching practices. Through the…
A Framework for Authenticity in the Mathematics and Statistics Classroom
Garrett, Lauretta; Huang, Li; Charleton, Maria Calhoun
2016-01-01
Authenticity is a term commonly used in reference to pedagogical and curricular qualities of mathematics teaching and learning, but its use lacks a coherent framework. The work of researchers in engineering education provides such a framework. Authentic qualities of mathematics teaching and learning are fit within a model described by Strobel,…
The mathematical theory of general relativity
Katkar, L N
2014-01-01
This book is prepared for M. Sc. Students of Mathematics and Physics. The aim of writing this book is to give the reader a feeling for the necessity and beauty of the laws of general relativity. The contents of the book will attract both mathematicians and physicists which provides motivation and applications of many ideas and powerful mathematical methods of modern analysis and differential geometry. An attempt has been made to make the presentation comprehensive, rigorous and yet simple. Most calculations and transformations have been carried out in great detail. KEY FEATURE: Numerous solved examples using the well known mathematical techniques viz., the tensors and the differential forms in each chapter.
Mathematical framework for traction force microscopy
Directory of Open Access Journals (Sweden)
Michel R.
2013-12-01
Full Text Available This paper deals with the Traction Force Microscopy (TFM problem. It consists in obtaining stresses by solving an inverse problem in an elastic medium, from known experimentally measured displacements. In this article, the application is the determination of the stresses exerted by a living cell at the surface of an elastic gel. We propose an abstract framework which formulates this inverse problem as a constrained minimization one. The mathematical constraints express the biomechanical conditions that the stress field must satisfy. From this framework, two methods currently used can be derived, the adjoint method (AM and the Fourier Transform Traction Cytometry (FTTC method. An improvement of the FTTC method is also derived using this framework. The numerical results are compared and show the advantage of the AM, in particular its ability to capture details more accurately. Cet article est consacré au problème de la Microscopie à Force de Traction (TFM. Ce problème consiste à déterminer les contraintes exercées par une cellule lors de sa migration sur un substrat élastique à partir d’une mesure expérimentale des déplacements induits dans ce substrat. Mathématiquement, il s’agit de résoudre un problème inverse pour lequel nous proposons une formulation abstraite de type optimisation sous contraintes. Les contraintes mathématiques expriment les constraintes biomécaniques que doit satisfaire le champ de contraintes exercé par la cellule. Ce cadre abstrait permet de retrouver deux des méthodes de résolution utilisées en pratique, à savoir la méthode adjointe (AM et la méthode de Cytométrie de Traction par Transformée de Fourier (FTTC. Il permet aussi d’ameliorer la méthode FTTC. Les résultats numériques obtenus sont ensuite comparés et démontrent l’avantage de la méthode adjointe, en particulier par sa capacité à capturer des détails avec une meilleure précision.
Affect in Mathematics Education--Exploring Theoretical Frameworks. Research Forum
Hannula, Markku; Evans, Jeff; Philippou, George; Zan, Rosetta
2004-01-01
This document brings into a dialogue some of the theoretical frameworks used to study affect in mathematics education. It presents affect as a representational system, affect as one regulator of the dynamic self, affect in a socio-constructivist framework, and affect as embodied. It also evaluates these frameworks from different perspectives:…
New and general framework for adsorption processes on dynamic interfaces
Schmuck, Markus
2013-01-01
We introduce a new and general continuum thermodynamic framework for the mathematical analysis and computation of adsorption on dynamic interfaces. To the best of our knowledge, there is no formulation available that accounts for the coupled dynamics of interfaces and densities of adsorbants. Our framework leads to analytic adsorption isotherms which also take the interfacial geometry fully into account. We demonstrate the utility and physical consistency of our framework with a new computational multi-level discretization strategy. In the computations, we recover the experimentally observed feature that the adsorption of particles minimizes the interfacial tension.
Wilson, John Martin, Jr.
The purpose of this study was to investigate the interrelationship of general mathematics skills, modern mathematics skills, modern mathematics achievement, prior mathematical attitudes, and postmathematical attitudes of prospective elementary teachers. A sample of 206 students was drawn from 286 students enrolled in a modern mathematics course.…
A Framework for Mathematical Thinking: The Case of Linear Algebra
Stewart, Sepideh; Thomas, Michael O. J.
2009-01-01
Linear algebra is one of the unavoidable advanced courses that many mathematics students encounter at university level. The research reported here was part of the first author's recent PhD study, where she created and applied a theoretical framework combining the strengths of two major mathematics education theories in order to investigate the…
A Framework for Mathematical Thinking: The Case of Linear Algebra
Stewart, Sepideh; Thomas, Michael O. J.
2009-01-01
Linear algebra is one of the unavoidable advanced courses that many mathematics students encounter at university level. The research reported here was part of the first author's recent PhD study, where she created and applied a theoretical framework combining the strengths of two major mathematics education theories in order to investigate the…
Mathematics Framework for the 2007 National Assessment of Educational Progress
Howe, Roger; Scheaffer, Richard; Lindquist, Mary
2006-01-01
This document contains the framework and a set of recommendations for the NAEP 2007 mathematics assessment, which will assess student achievement nationally and state-by-state, as well as in select urban districts, in grades 4 and 8. It includes descriptions of the mathematical content of the test, the types of test questions, and recommendations…
Theoretical Framework of Researcher Knowledge Development in Mathematics Education
Kontorovich, Igor'
2016-01-01
The goal of this paper is to present a framework of researcher knowledge development in conducting a study in mathematics education. The key components of the framework are: knowledge germane to conducting a particular study, processes of knowledge accumulation, and catalyzing filters that influence a researcher's decision making. The components…
Problem Solving Frameworks for Mathematics and Software Development
McMaster, Kirby; Sambasivam, Samuel; Blake, Ashley
2012-01-01
In this research, we examine how problem solving frameworks differ between Mathematics and Software Development. Our methodology is based on the assumption that the words used frequently in a book indicate the mental framework of the author. We compared word frequencies in a sample of 139 books that discuss problem solving. The books were grouped…
General framework for adsorption processes on dynamic interfaces
Schmuck, Markus; Kalliadasis, Serafim
2016-03-01
We propose a novel and general variational framework modelling particle adsorption mechanisms on evolving immiscible fluid interfaces. A by-product of our thermodynamic approach is that we systematically obtain analytic adsorption isotherms for given equilibrium interfacial geometries. We validate computationally our mathematical methodology by demonstrating the fundamental properties of decreasing interfacial free energies by increasing interfacial particle densities and of decreasing surface pressure with increasing surface area.
Mathematical properties of generalized Sturmian functions
Energy Technology Data Exchange (ETDEWEB)
Ambrosio, M J; Punta, J A Del; Rodriguez, K V; Gasaneo, G [Departamento de Fisica, Universidad Nacional del Sur and Consejo Nacional de Investigaciones Cientificas y Tecnicas, 8000 Bahia Blanca, Buenos Aires (Argentina); Ancarani, L U, E-mail: mja1984@gmail.com [Laboratoire de Physique Moleculaire et des Collisions, Universite Paul Verlaine-Metz, 57078 Metz (France)
2012-01-13
We study some mathematical properties of generalized Sturmian functions which are solutions of a Schroedinger-like equation supplemented by two boundary conditions. These generalized functions, for any value of the energy, are defined in terms of the magnitude of the potential. One of the boundary conditions is imposed at the origin of the coordinate, where regularity is required. The second point is at large distances. For negative energies, bound-like conditions are imposed. For positive or complex energies, incoming or outgoing boundary conditions are imposed to deal with scattering problems; in this case, since scattering conditions are complex, the Sturmian functions themselves are complex. Since all of the functions solve a Sturm-Liouville problem, they allow us to construct a Sturmian basis set which must be orthogonal and complete: this is the case even when they are complex. Here we study some properties of generalized Sturmian functions associated with the Hulthen potential, in particular, the spatial organization of their nodes, and demonstrate explicitly their orthogonality. We also show that the overlap matrix elements, which are generally required in scattering or bound state calculations, are well defined. Many of these mathematical properties are expressed in terms of uncommon multivariable hypergeometric functions. Finally, applications to the scattering of a particle by a Yukawa and by a Hulthen potential serve as illustrations of the efficiency of the complex Hulthen-Sturmian basis. (paper)
Game Design and Development as Mathematical Activities: Proposing a Framework
DEFF Research Database (Denmark)
Jensen, Erik Ottar; Hanghøj, Thorkild; Misfeldt, Morten
2016-01-01
to mathematical activities in two ways; developing computer games though programming languages can relate to algorithmic thinking and systems thinking is related to the game design process. The third aspect is the instrumental approach to computational artifacts mediation as a means of understanding the mediation......In this paper a framework for describing some of the mathematical activities inherent in computer game design is proposed in order to develop a framework for use in a recently conducted pilot study. The paper presents an introduction of previous work on the subject of game design and mathematics...... the game design process, mathematics as a subject, the pedagogical practices, as well as the students’ everyday experience with games. The second aspect presents algorithmic thinking and systems thinking as a basis for thinking in causalities, stochastic processes and consequences, which relates...
Mathematics subject classification and related schemes in the OAI framework
De Robbio, Antonella; Maguolo, Dario; Marini, Alberto
2002-01-01
This paper aims to give a feeling of the roles that discipline-oriented subject classifications can play in the Open Archive movement for the free dissemination of information in research activities. Mathematics, and Mathematics Subject Classification, will be the focuses around which we will move to discover a variety of presentation modes, protocols and tools for human and machine interoperability. The Open Archives Initiative (OAI) is intended to be the effective framework for such a play....
A general framework for reasoning on inconsistency
Martinez, Maria Vanina; Subrahmanian, VS; Amgoud, Leila
2013-01-01
This SpringerBrief proposes a general framework for reasoning about inconsistency in a wide variety of logics, including inconsistency resolution methods that have not yet been studied. The proposed framework allows users to specify preferences on how to resolve inconsistency when there are multiple ways to do so. This empowers users to resolve inconsistency in data leveraging both their detailed knowledge of the data as well as their application needs. The brief shows that the framework is well-suited to handle inconsistency in several logics, and provides algorithms to compute preferred opt
Barnett, Janet Heine; Lodder, Jerry; Pengelley, David
2014-01-01
We analyze our method of teaching with primary historical sources within the context of theoretical frameworks for the role of history in teaching mathematics developed by Barbin, Fried, Jahnke, Jankvist, and Kjeldsen and Blomhøj, and more generally from the perspective of Sfard's theory of learning as communication. We present case studies…
Barnett, Janet Heine; Lodder, Jerry; Pengelley, David
2014-01-01
We analyze our method of teaching with primary historical sources within the context of theoretical frameworks for the role of history in teaching mathematics developed by Barbin, Fried, Jahnke, Jankvist, and Kjeldsen and Blomhøj, and more generally from the perspective of Sfard's theory of learning as communication. We present case studies…
Assessing Mathematics: 1. APU Framework and Modes of Assessment.
Foxman, Derek; Mitchell, Peter
1983-01-01
The "what" and "how" of the Assessment of Performance Unit surveys of the mathematics performance of 11- and 15-year-olds in England, Wales, and Northern Ireland are explained. The framework and forms of assessment are detailed, and the experience of the testers noted. (MNS)
Adapting Technological Pedagogical Content Knowledge Framework to Teach Mathematics
Getenet, Seyum Tekeher
2017-01-01
The technological pedagogical content knowledge framework is increasingly in use by educational technology researcher as a generic description of the knowledge requirements for teachers using technology in all subjects. This study describes the development of a mathematics specific variety of the technological pedagogical content knowledge…
A General Framework of Automorphic Inflation
Schimmrigk, Rolf
2015-01-01
Automorphic inflation is an application of the framework of automorphic scalar field theory, based on the theory of automorphic forms and representations. In this paper the general framework of automorphic and modular inflation is described in some detail, with emphasis on the resulting stratification of the space of scalar field theories in terms of the group theoretic data associated to the shift symmetry, as well as the automorphic data that specifies the potential. The class of theories based on Eisenstein series provides a natural generalization of the model of $j$-inflation considered previously.
A General Framework for Probabilistic Characterizing Formulae
DEFF Research Database (Denmark)
Sack, Joshua; Zhang, Lijun
2012-01-01
a general method for determining characteristic formulae of behavioral relations for probabilistic automata using fixed-point probability logics. We consider such behavioral relations as simulations and bisimulations, probabilistic bisimulations, probabilistic weak simulations, and probabilistic forward......Recently, a general framework on characteristic formulae was proposed by Aceto et al. It offers a simple theory that allows one to easily obtain characteristic formulae of many non-probabilistic behavioral relations. Our paper studies their techniques in a probabilistic setting. We provide...
A General Framework for Reviewing Dictionaries
DEFF Research Database (Denmark)
Nielsen, Sandro
2013-01-01
in specific types of situations in the real (extra-lexicographic) world. I propose a basis for a framework that contains an outline of general theoretical and practical principles that underlie the true nature of dictionary reviews, and places the reviews in a lexicographic universe with the dictionary...
A General Framework for Reviewing Dictionaries
DEFF Research Database (Denmark)
Nielsen, Sandro
2011-01-01
in specific types of situations in the real (extra-lexicographic) world. I propose a basis for a framework that contains an outline of general theoretical and practical principles that underlie the true nature of dictionary reviews, and places the reviews in a lexicographic universe with the dictionary...
General framework for bridge life cycle design
Institute of Scientific and Technical Information of China (English)
Junhai MA; Airong CHEN; Jun HE
2009-01-01
Based on a detailed illustration for bridge life cycle design which comprises the processes of service life design, aesthetics design, performance design, environ-mental and ecological design, inspection, maintenance and repair design as well as cost analysis, this paper presented a general framework for bridge life cycle design comprising three design phases and six design processes.
A General Framework for Reviewing Dictionaries
DEFF Research Database (Denmark)
Nielsen, Sandro
2011-01-01
in specific types of situations in the real (extra-lexicographic) world. I propose a basis for a framework that contains an outline of general theoretical and practical principles that underlie the true nature of dictionary reviews, and places the reviews in a lexicographic universe with the dictionary...
Communication over Individual Channels -- a general framework
Lomnitz, Yuval
2012-01-01
We consider the problem of communicating over a channel for which no mathematical model is specified, and the achievable rates are determined as a function of the channel input and output sequences known a-posteriori, without assuming any a-priori relation between them. In a previous paper we have shown that the empirical mutual information between the input and output sequences is achievable without specifying the channel model, by using feedback and common randomness, and a similar result for real-valued input and output alphabets. In this paper, we present a unifying framework which includes the two previous results as particular cases. We characterize the region of rate functions which are achievable, and show that asymptotically the rate function is equivalent to a conditional distribution of the channel input given the output. We present a scheme that achieves these rates with asymptotically vanishing overheads.
Mathematical Framework for A Novel Database Replication Algorithm
Directory of Open Access Journals (Sweden)
Divakar Singh Yadav
2013-10-01
Full Text Available In this paper, the detailed overview of the database replication is presented. Thereafter, PDDRA (Pre-fetching based dynamic data replication algorithm algorithm as recently published is detailed. In this algorithm, further, modifications are suggested to minimize the delay in data replication. Finally a mathematical framework is presented to evaluate mean waiting time before a data can be replicated on the requested site.
GENERAL TASKS OF MATHEMATICAL EDUCATION DEVELOPMENT
Directory of Open Access Journals (Sweden)
V. A. Testov
2014-01-01
Full Text Available The paper discusses basic implementation aspects of the Mathematical Education Development Concept, adopted by the Russian Government in 2013. According to the above document, the main problems of mathematical education include: low motivation of secondary and higher school students for studying the discipline, resulted from underestimation of mathematical knowledge; and outdated educational content, overloaded by technical elements. In the author’s opinion, a number of important new mathematical fields, developed over the last years, - the graph theory, discrete mathematics, encoding theory, fractal geometry, etc – have a large methodological and applied educational potential. However, these new subdisciplines have very little representation both in the secondary and higher school mathematical curricula. As a solution for overcoming the gap between the latest scientific achievements and pedagogical practices, the author recommends integration of the above mentioned mathematical disciplines in educational curricula instead of some outdated technical issues. In conclusion, the paper emphasizes the need for qualified mathematical teachers’ training for solving the problems of students’ motivation development and content updates.
Market valuation in the framework of modern life insurance mathematics
Directory of Open Access Journals (Sweden)
Maja Petrač
2013-12-01
Full Text Available In the traditional actuarial life insurance mathematics, liabilities to beneficiaries (technical reserves are calculated based on conservative assumptions of mortality and interest rates. However, this approach was found to be incomplete since it does not contain the market component which has become essential due to the development of the financial market. Since about 80% of total liabilities of life insurance companies are made up of technical reserves, this issue has a major impact on the overall performance of insuran - ce companies. The introduction of financial components into the actuarial valuation resulted in actuarial mathematics using more and more the elements of financial mathematics thus creating new, modern life insurance mathematics. Using a simple example, this paper compares the traditional and market approaches to valuation. For this purpose, one of the principles of modern life insurance mathematics, the principle of equivalence, was observed. The above market approach to valuation, together with operational risk management, forms the basis of Solvency II Directive, the new legislative and regulatory framework for insurance and reinsurance companies in the European Union.
Aspects of Theories, Frameworks and Paradigms in Mathematics Education Research
Stoilescu, Dorian
2016-01-01
This article discusses major theoretical debates and paradigms from the last decades in general education and their specific influences in mathematics education contexts. Behaviourism, cognitive science, constructivism, situated cognition, critical theory, place-based learning, postmodernism and poststructuralism and their significant aspects in…
A general framework for parametric survival analysis.
Crowther, Michael J; Lambert, Paul C
2014-12-30
Parametric survival models are being increasingly used as an alternative to the Cox model in biomedical research. Through direct modelling of the baseline hazard function, we can gain greater understanding of the risk profile of patients over time, obtaining absolute measures of risk. Commonly used parametric survival models, such as the Weibull, make restrictive assumptions of the baseline hazard function, such as monotonicity, which is often violated in clinical datasets. In this article, we extend the general framework of parametric survival models proposed by Crowther and Lambert (Journal of Statistical Software 53:12, 2013), to incorporate relative survival, and robust and cluster robust standard errors. We describe the general framework through three applications to clinical datasets, in particular, illustrating the use of restricted cubic splines, modelled on the log hazard scale, to provide a highly flexible survival modelling framework. Through the use of restricted cubic splines, we can derive the cumulative hazard function analytically beyond the boundary knots, resulting in a combined analytic/numerical approach, which substantially improves the estimation process compared with only using numerical integration. User-friendly Stata software is provided, which significantly extends parametric survival models available in standard software. Copyright © 2014 John Wiley & Sons, Ltd.
Barnett, Janet Heine; Lodder, Jerry; Pengelley, David
2013-07-01
We analyze our method of teaching with primary historical sources within the context of theoretical frameworks for the role of history in teaching mathematics developed by Barbin, Fried, Jahnke, Jankvist, and Kjeldsen and Blomhøj, and more generally from the perspective of Sfard's theory of learning as communication. We present case studies for two of our guided student modules that are built around sequences of primary sources and are intended for learning core curricular material, one on logical implication, the other on the concept of a group. Additionally, we propose some conclusions about the advantages and challenges of using primary sources in teaching mathematics.
Wu, Haiyan
2013-01-01
General diagnostic models (GDMs) and Bayesian networks are mathematical frameworks that cover a wide variety of psychometric models. Both extend latent class models, and while GDMs also extend item response theory (IRT) models, Bayesian networks can be parameterized using discretized IRT. The purpose of this study is to examine similarities and…
Kollosche, David
2016-01-01
Socio-political studies in mathematics education often touch complex fields of interaction between education, mathematics and the political. In this paper I present a Foucault-based framework for socio-political studies in mathematics education which may guide research in that area. In order to show the potential of such a framework, I discuss the…
Kollosche, David
2016-01-01
Socio-political studies in mathematics education often touch complex fields of interaction between education, mathematics and the political. In this paper I present a Foucault-based framework for socio-political studies in mathematics education which may guide research in that area. In order to show the potential of such a framework, I discuss the…
Technology, Active Learning, and Retention in General Education Mathematics
Levi, Inessa; Chahine, Iman; Garrett, Lauretta; Wang, Haifeng
2016-01-01
Difficulties in general education mathematics courses may be attributed to many factors, primarily low proficiency in symbol manipulation, a perception that mathematics is an area which eludes mastery, a lack of engagement and effective practice. Educational technology can be a powerful aid in overcoming these factors. This work describes the…
General Framework of Hearing Aid Fitting Management.
Oh, Soo Hee; Lee, Junghak
2016-04-01
Hearing aids are one of the most widely used treatment options for the hearing impaired and optimal outcomes of hearing aids are supported by comprehensive hearing aid fitting protocols. Currently, the term 'hearing aid fitting' is prevalently used among service and industry sectors with its comprehensive procedures not systematically explicated. In addition, a variety of non-normalized guidelines for hearing aid fitting has led to non-uniform care, outcome variability, and dissatisfaction of the use of hearing aids. The main purpose of the present study is to suggest a general framework of standardized practice for hearing aid fitting management including its pre- and post-fitting stages. The management framework centers on its fitting process with its prior steps of assessment as well as its posterior steps of follow-up, thereby eliminating diverging interpretations and non-uniform practices. Outcomes of this study are also expected to improve potential benefits such as quality of hearing aid fitting, user satisfaction, and cost effectiveness across relevant stakeholders.
Generalized Mathematical Model for Hot Rolling Process of Plate
Institute of Scientific and Technical Information of China (English)
Zhenshan CUI; Bingye XU
2003-01-01
A generalized mathematical model is developed to predict the changes of temperature, rolling pressure, strain,strain rate, and austenite grain size for plate hot rolling and cooling processes. The model is established mainly by incorporating analytical an
The general theory of relativity a mathematical exposition
Das, Anadijiban
2012-01-01
The General Theory of Relativity: A Mathematical Exposition will serve readers as a modern mathematical introduction to the general theory of relativity. Throughout the book, examples, worked-out problems, and exercises (with hints and solutions) are furnished. Topics in this book include, but are not limited to: • tensor analysis • the special theory of relativity • the general theory of relativity and Einstein’s field equations • spherically symmetric solutions and experimental confirmations • static and stationary space-time domains • black holes • cosmological models • algebraic classifications and the Newman-Penrose equations • the coupled Einstein-Maxwell-Klein-Gordon equations • appendices covering mathematical supplements and special topics Mathematical rigor, yet very clear presentation of the topics make this book a unique text for both university students and research scholars. Anadijiban Das has taught courses on Relativity Theory at The University College of Dublin, Irelan...
Life Cycle Inventory Analysis of Recycling: Mathematical and Graphical Frameworks
Directory of Open Access Journals (Sweden)
Jun Nakatani
2014-09-01
Full Text Available A mathematical framework of the life cycle inventory (LCI analysis in life cycle assessment (LCA of recycling is systematically reviewed with the aid of graphical interpretation. First, the zero burden approach, which has been applied to LCI analyses of waste management systems, is theoretically justified in terms of relative comparison of waste management options. As recycling is a multi-functional system including the dual functions of waste management and secondary material production, the allocation issue needs to be handled in LCIs of recycling, and two forms of system expansion, i.e., the avoided burden and product basket approaches, have dominated to avoid the allocation problem. Then, it is demonstrated that conclusions derived from both approaches should mathematically be identical as far as system boundaries are correctly defined. A criticism against system expansion is also reviewed from the viewpoint of ambiguity of what-if scenarios. As an approach to this issue, market-based consequential LCA is discussed in the context of LCI analyses of open-loop recycling.
General Mission Analysis Tool (GMAT) Mathematical Specifications
Hughes, Steve
2007-01-01
The General Mission Analysis Tool (GMAT) is a space trajectory optimization and mission analysis system developed by NASA and private industry in the spirit of the NASA Mission. GMAT contains new technology and is a testbed for future technology development.
CHI: A General Agent Communication Framework
Energy Technology Data Exchange (ETDEWEB)
Goldsmith, S.Y.; Phillips, L.R.; Spires, S.V.
1998-12-17
We have completed and exercised a communication framework called CHI (CLOS to HTML Interface) by which agents can communicate with humans. CHI follows HTTP (HyperText Transfer Protocol) and produces HTML (HyperText Markup Language) for use by WWW (World-Wide Web) browsers. CHI enables the rapid and dynamic construction of interface mechanisms. The essence of CHI is automatic registration of dynamically generated interface elements to named objects in the agent's internal environment. The agent can access information in these objects at will. State is preserved, so an agent can pursue branching interaction sequences, activate failure recovery behaviors, and otherwise act opportunistically to maintain a conversation. The CHI mechanism remains transparent in multi-agent, multi-user environments because of automatically generated unique identifiers built into the CHI mechanism. In this paper we discuss design, language, implementation, and extension issues, and, by way of illustration, examine the use of the general CHI/HCHI mechanism in a specific international electronic commerce system. We conclude that the CHI mechanism is an effective, efficient, and extensible means of the agent/human communication.
Ryve, Andreas
2006-01-01
Sfard and Kieran [Kieran, C., Educational Studies in Mathematics 46, 2001, 187-228; Sfard, A., Educational Studies in Mathematics 46, 2001, 13-57; Sfard, A. and Kieran, C., Mind, Culture, and Activity 8, 2001, 42-76] have developed a methodological framework, which aims at characterizing the students' mathematical discourses while they are working…
Komatsu, Kotaro
2016-01-01
The process of proofs and refutations described by Lakatos is essential in school mathematics to provide students with an opportunity to experience how mathematical knowledge develops dynamically within the discipline of mathematics. In this paper, a framework for describing student processes of proofs and refutations is constructed using a set of…
General relativity and mathematics; Relatividad General y Matematicas
Energy Technology Data Exchange (ETDEWEB)
Mars, M.
2015-07-01
General relativity is more than a theory of gravity, since any physical process occupies space and lasts for a time, forcing to reconcile that physical theory that describes what the dynamic nature of space-time itself. (Author)
NetMOD Version 2.0 Mathematical Framework
Energy Technology Data Exchange (ETDEWEB)
Merchant, Bion J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Young, Christopher J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Chael, Eric P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2015-08-01
NetMOD ( Net work M onitoring for O ptimal D etection) is a Java-based software package for conducting simulation of seismic, hydroacoustic and infrasonic networks. Network simulations have long been used to study network resilience to station outages and to determine where additional stations are needed to reduce monitoring thresholds. NetMOD makes use of geophysical models to determine the source characteristics, signal attenuation along the path between the source and station, and the performance and noise properties of the station. These geophysical models are combined to simulate the relative amplitudes of signal and noise that are observed at each of the stations. From these signal-to-noise ratios (SNR), the probabilities of signal detection at each station and event detection across the network of stations can be computed given a detection threshold. The purpose of this document is to clearly and comprehensively present the mathematical framework used by NetMOD, the software package developed by Sandia National Laboratories to assess the monitoring capability of ground-based sensor networks. Many of the NetMOD equations used for simulations are inherited from the NetSim network capability assessment package developed in the late 1980s by SAIC (Sereno et al., 1990).
A Curriculum Innovation Framework for Science, Technology and Mathematics Education
Tytler, Russell; Symington, David; Smith, Craig
2011-01-01
There is growing concern about falling levels of student engagement with school science, as evidenced by studies of student attitudes, and decreasing participation at the post compulsory level. One major response to this, the Australian School Innovation in Science, Technology and Mathematics (ASISTM) initiative, involves partnerships between schools and community and industry organisations in developing curriculum projects at the local level. This project fulfils many of the conditions advocated to engage students in learning in the sciences. ASISTM is underpinned by the notion of innovation. This paper describes the findings of case study research in which 16 ASISTM projects were selected as innovation exemplars. A definition of innovation and an innovation framework were developed, through which the case studies were analysed to make sense of the significance of the ideas and practices, participating actors, and outcomes of the projects. Through this analysis we argue that innovation is a powerful idea for framing curriculum development in the sciences at the local level that is generative for students and teachers, and that these ASISTM projects provide valuable models for engaging students, and for teacher professional learning.
A Conceptual Metaphor Framework for the Teaching of Mathematics
Danesi, Marcel
2007-01-01
Word problems in mathematics seem to constantly pose learning difficulties for all kinds of students. Recent work in math education (for example, [Lakoff, G. & Nunez, R. E. (2000). "Where mathematics comes from: How the embodied mind brings mathematics into being." New York: Basic Books]) suggests that the difficulties stem from an…
Game Show Mathematics: Specializing, Conjecturing, Generalizing, and Convincing
Lane, Catherine Pullin; Harkness, Shelly Sheats
2012-01-01
This article describes the authors' use of three game shows--"Survivor," "The Biggest Loser," and "Deal or No Deal?"--to determine to what degree students engaged in mathematical thinking: specializing, conjecturing, generalizing, and convincing (Burton, 1984). Student responses to the task of creating winning strategies to these shows were…
Generalizing Prototype Theory: A Formal Quantum Framework
Directory of Open Access Journals (Sweden)
Diederik eAerts
2016-03-01
Full Text Available Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper.
Generalizing Prototype Theory: A Formal Quantum Framework.
Aerts, Diederik; Broekaert, Jan; Gabora, Liane; Sozzo, Sandro
2016-01-01
Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper.
Generalizing Prototype Theory: A Formal Quantum Framework
Aerts, Diederik; Broekaert, Jan; Gabora, Liane; Sozzo, Sandro
2016-01-01
Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper. PMID:27065436
Tuminaro, Jonathan
Many introductory, algebra-based physics students perform poorly on mathematical problem solving tasks in physics. There are at least two possible, distinct reasons for this poor performance: (1) students simply lack the mathematical skills needed to solve problems in physics, or (2) students do not know how to apply the mathematical skills they have to particular problem situations in physics. While many students do lack the requisite mathematical skills, a major finding from this work is that the majority of students possess the requisite mathematical skills, yet fail to use or interpret them in the context of physics. In this thesis I propose a theoretical framework to analyze and describe students' mathematical thinking in physics. In particular, I attempt to answer two questions. What are the cognitive tools involved in formal mathematical thinking in physics? And, why do students make the kinds of mistakes they do when using mathematics in physics? According to the proposed theoretical framework there are three major theoretical constructs: mathematical resources, which are the knowledge elements that are activated in mathematical thinking and problem solving; epistemic games, which are patterns of activities that use particular kinds of knowledge to create new knowledge or solve a problem; and frames, which are structures of expectations that determine how individuals interpret situations or events. The empirical basis for this study comes from videotaped sessions of college students solving homework problems. The students are enrolled in an algebra-based introductory physics course. The videotapes were transcribed and analyzed using the aforementioned theoretical framework. Two important results from this work are: (1) the construction of a theoretical framework that offers researchers a vocabulary (ontological classification of cognitive structures) and grammar (relationship between the cognitive structures) for understanding the nature and origin of
Gruetzmann, Melchior
2014-01-01
Starting with minimal requirements from the physical experience with higher gauge theories, i.e. gauge theories for a tower of differential forms of different form degrees, we discover that all the structural identities governing such theories can be concisely recombined into a so-called Q-structure or, equivalently, a Lie infinity algebroid. This has many technical and conceptual advantages: Complicated higher bundles become just bundles in the category of Q-manifolds in this approach (the many structural identities being encoded in the one operator Q squaring to zero), gauge transformations are generated by internal vertical automorphisms in these bundles and even for a relatively intricate field content the gauge algebra can be determined in some lines only and is given by the so-called derived bracket construction. This article aims equally at mathematicians and theoretical physicists; each more physical section is followed by a purely mathematical one. While the considerations are valid for arbitrary hig...
A Framework for Teachers' Knowledge of Mathematical Reasoning
Herbert, Sandra
2014-01-01
Exploring and developing primary teachers' understanding of mathematical reasoning was the focus of the "Mathematical Reasoning Professional Learning Research Program." Twenty-four primary teachers were interviewed after engagement in the first stage of the program incorporating demonstration lessons focused on reasoning conducted in…
General framework for the reconfiguration of satellite constellations
Ferringer, Matthew Phillip
From remote sensing to navigation and communication, satellite constellations have become an indispensible component of our society's infrastructure. Recent events, including China's intercept of their Feng Yun-1C weather satellite and the United States' intercept of a non-functioning satellite, have dramatically increased the amount of space debris, which poses an increased risk for on-orbit collisions. When the loss or degradation of a satellite in a constellation is experienced---be it from a collision with space debris, on-orbit malfunctions, or natural causes---the constellation may no longer be capable of fulfilling its mission requirements. Instead of simply accepting the degraded performance, stakeholders may consider reconfiguration of the remaining spacecraft. In this research, a general framework for the reconfiguration of satellite constellations is developed. The key characteristic that separates this research from others that have come before it is that the future state of the reconfigured constellation is not assumed a priori; rather, it is this state that is found. In other words, the reconfigured geometry can occupy any feasible region (this is mission dependent) of the design space in an attempt to provide optimal performance with respect to multiple-criterion. These include the propellant expended, time of transfer, reduction in mission life, coverage performance, and risk due to maneuvering. When modeled as mathematical functions, some of these concerns exhibit continuous behavior; however, most have nonlinear, discrete, discontinuous, and/or multimodal characteristics. The framework adapts a best-in-class parallel Multi-Objective Evolutionary Algorithm to approximate the optimal hypervolumes for this complex tradeoff-space. Several loss scenarios for the Global Positioning System constellation are presented to demonstrate the framework. An a posteriori procedure for decision support is introduced that enables down-selection to a final design
The Importance of Theoretical Frameworks and Mathematical Constructs in Designing Digital Tools
Trinter, Christine
2016-01-01
The increase in availability of educational technologies over the past few decades has not only led to new practice in teaching mathematics but also to new perspectives in research, methodologies, and theoretical frameworks within mathematics education. Hence, the amalgamation of theoretical and pragmatic considerations in digital tool design…
The Importance of Theoretical Frameworks and Mathematical Constructs in Designing Digital Tools
Trinter, Christine
2016-01-01
The increase in availability of educational technologies over the past few decades has not only led to new practice in teaching mathematics but also to new perspectives in research, methodologies, and theoretical frameworks within mathematics education. Hence, the amalgamation of theoretical and pragmatic considerations in digital tool design…
A Framework for Examining Mathematics Teacher Knowledge as Used in Error Analysis
Peng, Aihui; Luo, Zengru
2009-01-01
Error analysis is a basic and important task for mathematics teachers. Unfortunately, in the present literature there is a lack of detailed understanding about teacher knowledge as used in it. Based on a synthesis of the literature in error analysis, a framework for prescribing and assessing mathematics teacher knowledge in error analysis was…
Grützmann, Melchior; Strobl, Thomas
2015-10-01
Starting with minimal requirements from the physical experience with higher gauge theories, i.e. gauge theories for a tower of differential forms of different form degrees, we discover that all the structural identities governing such theories can be concisely recombined into what is called a Q-structure or, equivalently, an L∞-algebroid. This has many technical and conceptual advantages: complicated higher bundles become just bundles in the category of Q-manifolds in this approach (the many structural identities being encoded in the one operator Q squaring to zero), gauge transformations are generated by internal vertical automorphisms in these bundles and even for a relatively intricate field content the gauge algebra can be determined in some lines and is given by what is called the derived bracket construction. This paper aims equally at mathematicians and theoretical physicists; each more physical section is followed by a purely mathematical one. While the considerations are valid for arbitrary highest form degree p, we pay particular attention to p = 2, i.e. 1- and 2-form gauge fields coupled nonlinearly to scalar fields (0-form fields). The structural identities of the coupled system correspond to a Lie 2-algebroid in this case and we provide different axiomatic descriptions of those, inspired by the application, including e.g. one as a particular kind of a vector-bundle twisted Courant algebroid.
Knowledge spillovers from FDI: Towards a general framework
Vaal, A. de; Smeets, R.A.L.M.
2005-01-01
This paper develops a conceptual framework that allows for a consistent and coherent treatment of knowledge spillovers from FDI. In this framework, three aspects play a crucial role. First, FDI is a general notion that actually comprises a host of different investment types. Second, the number
Active structural elements within a general vibration control framework
Holterman, J.; de Vries, Theodorus J.A.; Isermann, R.
2000-01-01
High-precision machines typically suffer from small but annoying vibrations. As the most appropriate solution to a particular vibration problem is not always obvious, it may be convenient to cast the problem in a more general framework. This framework may then be used for frequency response
A General Framework for Reviewing Dictionaries
DEFF Research Database (Denmark)
Nielsen, Sandro
2013-01-01
The reviewing of electronic and printed dictionaries is not an exercise in linguistics or in subject fields but an exercise in lexicography. It does not follow from this that dictionary reviews cannot or should not be based on a linguistic approach, but that the linguistic approach is only one...... and lexicography at its centre. This seems to be in line with the modern understanding of lexicography as a separate academic discipline concerned with the compilation, design, evaluation and use of dictionaries. Moreover, a set of generally applicable principles may lead the discourse community to accept...
Active structural elements within a general vibration control framework
Holterman, J.; de Vries, Theodorus J.A.; Isermann, R.
2000-01-01
High-precision machines typically suffer from small but annoying vibrations. As the most appropriate solution to a particular vibration problem is not always obvious, it may be convenient to cast the problem in a more general framework. This framework may then be used for frequency response analysis, which, together with close examination of the disturbance sources, leads to a solution in general structural terms, like ‘vibration isolation’, ‘stiffness enhancement’ or ‘damping augmentation’. ...
De Robbio, Antonella; Maguolo, Dario; Marini, Alberto
2002-01-01
This paper aims to give a feeling of the roles that discipline-oriented subject classifications can play in the Open Archive movement for the free dissemination of information in research activities. Mathematics, and Mathematics Subject Classification, will be the focuses around which we will move to discover a variety of presentation modes, protocols and tools for human and machine interoperability. The Open Archives Initiative (OAI) is intended to be the effective framework for such a...
A generalization of Dung's Abstract Framework for Argumentation
DEFF Research Database (Denmark)
Nielsen, Søren Holbech; Parsons, Simon
2006-01-01
One of the most widely studied systems of argumentation is the one described by Dung in a paper from 1995. Unfortunately, this framework does not allow for joint attacks on arguments, which we argue must be required of any truly abstract argumentation framework. A few frameworks can be said...... to allow for such interactions among arguments, but for various reasons we believe that these are inadequate for modelling argumentation systems with joint attacks. In this paper we propose a generalization of the framework of Dung, which allows for sets of arguments to attack other arguments. We extend...
Toward Nexus Equation: A Conceptual and Mathematical Framework for Water- Energy-Food Nexus
Abou Najm, Majdi; Higgins, Chad
2016-04-01
Water, energy, and agriculture are highly interdependent that attempts to achieve sustainability in any of those three domains will directly impact the others. These interdependencies, collectively known as the Water-Energy-Food Nexus, become more complex and more critical as the climate changes, the population grows, habits and lifestyles alternate, and the prices of water, energy, and food increase. However, and despite several attempts to incorporate the nexus, the global research community continues to focus on different subsets of the problem with limited holistic attempts to address the full problem. At best, interactions between two of the three domains were studied, often neglecting the impact of such interaction on the third domain. For example, agricultural researchers tracked water costs by applying concepts like virtual water or water footprint, or using large-scale system models to investigate food and water security, ignoring most often the corresponding energy footprint. Similarly, investigators quantified water-energy tradeoffs in the highly engineered, centralized systems of water and power management, paying no attention to water diversion from agriculture. Most nexus initiatives focused on reviews and data collection of existing knowledge and relevant facts, but unfortunately lacked a conceptual and mathematical framework that can integrate all the gathered knowledge and account for multiple interactions, feedbacks, or natural processes that occur across all three domains of the nexus. Here, we present an integrated conceptual and mathematical framework (roadmap) for the nexus. This framework is driven by spatiotemporal demands for water, energy, and food to be satisfied by resource management of the three domains, envisioned as a stepwise process, with each step requiring inputs from the three nexus domains and creating waste products. The efficiency of each step, combined with mass balances, create the linkages and feedback loops within the
An Exploratory Framework for Handling the Complexity of Mathematical Problem Posing in Small Groups
Kontorovich, Igor; Koichu, Boris; Leikin, Roza; Berman, Avi
2012-01-01
The paper introduces an exploratory framework for handling the complexity of students' mathematical problem posing in small groups. The framework integrates four facets known from past research: task organization, students' knowledge base, problem-posing heuristics and schemes, and group dynamics and interactions. In addition, it contains a new…
An Initial Framework for the Language of Higher-Order Thinking Mathematics Practices
Staples, Megan E.; Truxaw, Mary P.
2012-01-01
This article presents an examination of the language demands of cognitively demanding tasks and proposes an initial framework for the language demands of higher-order mathematics thinking practices. We articulate four categories for this framework: "language of generalisation," "language of comparison," "language of proportional reasoning," and…
Translation Accommodations Framework for Testing English Language Learners in Mathematics
Solano-Flores, Guillermo
2012-01-01
The present framework is developed under contract with the Smarter Balanced Assessment Consortium (SBAC) as a conceptual and methodological tool for guiding the reasonings and actions of contractors in charge of developing and providing test translation accommodations for English language learners. The framework addresses important challenges in…
Schubert, Martin
2012-01-01
This book develops a mathematical framework for modeling and optimizing interference-coupled multiuser systems. At the core of this framework is the concept of general interference functions, which provides a simple means of characterizing interdependencies between users. The entire analysis builds on the two core axioms scale-invariance and monotonicity. The proposed network calculus has its roots in power control theory and wireless communications. It adds theoretical tools for analyzing the typical behavior of interference-coupled networks. In this way it complements existing game-theoretic approaches. The framework should also be viewed in conjunction with optimization theory. There is a fruitful interplay between the theory of interference functions and convex optimization theory. By jointly exploiting the properties of interference functions, it is possible to design algorithms that outperform general-purpose techniques that only exploit convexity. The title “network calculus” refers to the fact tha...
A Mathematical Modeling Framework for Analysis of Functional Clothing
Directory of Open Access Journals (Sweden)
Xiaolin Man
2007-11-01
Full Text Available In the analysis and design of functional clothing systems, it is helpful to quantify the effects of a system on a wearer’s physical performance capabilities. Toward this end, a clothing modeling framework for quantifying the mechanical interactions between a given clothing system design and a specific wearer performing defined physical tasks is proposed. The modeling framework consists of three interacting modules: (1 a macroscale fabric mechanics/dynamics model; (2 a collision detection and contact correction module; and (3 a human motion module. In the proposed framework, the macroscopic fabric model is based on a rigorous large deformation continuum-degenerated shell theory representation. Material models that capture the stress-strain behavior of different clothing fabrics are used in the continuum shell framework. The collision and contact module enforces the impenetrability constraint between the fabric and human body and computes the associated contact forces between the two. The human body is represented in the current framework as an assemblage of overlapping ellipsoids that undergo rigid body motions consistent with human motions while performing actions such as walking, running, or jumping. The transient rigid body motions of each ellipsoidal body segment in time are determined using motion capture technology. The integrated modeling framework is then exercised to quantify the resistance that the clothing exerts on the wearer during the specific activities under consideration. Current results from the framework are presented and its intended applications are discussed along with some of the key challenges remaining in clothing system modeling.
Programming-Languages as a Conceptual Framework for Teaching Mathematics
Feurzeig, Wallace; Papert, Seymour A.
2011-01-01
Formal mathematical methods remain, for most high school students, mysterious, artificial and not a part of their regular intuitive thinking. The authors develop some themes that could lead to a radically new approach. According to this thesis, the teaching of programming languages as a regular part of academic progress can contribute effectively…
A Curriculum Innovation Framework for Science, Technology and Mathematics Education
Tytler, Russell; Symington, David; Smith, Craig
2011-01-01
There is growing concern about falling levels of student engagement with school science, as evidenced by studies of student attitudes, and decreasing participation at the post compulsory level. One major response to this, the Australian School Innovation in Science, Technology and Mathematics (ASISTM) initiative, involves partnerships between…
A General Framework for Measuring VAT Compliance Rates
J. A. Giesecke; Tran Hoang Nhi
2010-01-01
Summary measures of VAT compliance rates are valuable for identifying problem areas in VAT implementation. They are also essential for meaningful cross-country and cross-time comparisons of VAT compliance. We present a comprehensive and general framework for calculating VAT compliance rates at both the economy-wide and detailed sectoral levels. Unlike existing measures of VAT compliance, our framework isolates a compliance measure from the effects on VAT receipts of detailed features of VAT s...
Mathematical model and general laws of wet compression
Institute of Scientific and Technical Information of China (English)
王永青; 刘铭; 廉乐明; 何健勇; 严家騄
2002-01-01
Wet compression is an effective way to enhance the performance of gas turbines and it has attracted a good deal of attention in recent years. The one-sidedness and inaccuracy of previous studies,which took concentration gradient as mass transfer potential are discussed. The mass transfer process is analyzed from the viewpoint of non-equilibrium thermodynamics,by taking generalized thermodynamic driving force as mass transfer potential,and the corresponding mass-transfer coefficient is obtained using the heat and mass transfer equilibrium occurring between moist air and water droplets at wet-bulb temperature for the sake of avoiding complex tests and providing more accurate formulas. A mathematical model of wet compression is therefore established,and the general laws of wet compression are investigated. The results show that the performance of atomizer is critical for wet compression and wet compression is more suitable for compressors with higher pressure ratio and longer compression time.
A framework for designing a research-based "mathematics counsellor" teacher programme
DEFF Research Database (Denmark)
Niss, Mogens Allan; Thomas Jankvist, Uffe
2015-01-01
This article addresses one way in which decades of mathematics education research results can inform practice, by offering a framework for designing and implementing an in-service teacher education programme for upper secondary mathematics teachers in Denmark. The programme aims to educate a “task...... force” of so-called “maths counsellors”, i.e., mathematics teachers whose goal it is to help identify students with genuine learning difficulties in mathematics, investigate the nature of these difficulties, and carry out research-based interventions to assist the students in overcoming them. We present...... and discuss the various components of the programme, theoretical as well as practical, and account for how these make up a framework for designing a research-based “maths counsellor” teacher programme...
ACER: A Framework on the Use of Mathematics in Upper-division Physics
Caballero, Marcos D; Pepper, Rachel E; Pollock, Steven J
2012-01-01
At the University of Colorado Boulder, as part of our broader efforts to transform middle- and upper-division physics courses, we research students' difficulties with particular concepts, methods, and tools in classical mechanics, electromagnetism, and quantum mechanics. Unsurprisingly, a number of difficulties are related to students' use of mathematical tools (e.g., approximation methods). Previous work has documented a number of challenges that students must overcome to use mathematical tools fluently in introductory physics (e.g., mapping meaning onto mathematical symbols). We have developed a theoretical framework to facilitate connecting students' difficulties to challenges with specific mathematical and physical concepts. In this paper, we motivate the need for this framework and demonstrate its utility for both researchers and course instructors by applying it to frame results from interview data on students' use of Taylor approximations.
ACER: A framework on the use of mathematics in upper-division physics
Caballero, Marcos D.; Wilcox, Bethany R.; Pepper, Rachel E.; Pollock, Steven J.
2013-01-01
At the University of Colorado Boulder, as part of our broader efforts to transform middle- and upper-division physics courses, we research students' difficulties with particular concepts, methods, and tools in classical mechanics, electromagnetism, and quantum mechanics. Unsurprisingly, a number of difficulties are related to students' use of mathematical tools (e.g., approximation methods). Previous work has documented a number of challenges that students must overcome to use mathematical tools fluently in introductory physics (e.g., mapping meaning onto mathematical symbols). We have developed a theoretical framework to facilitate connecting students' difficulties to challenges with specific mathematical and physical concepts. In this paper, we motivate the need for this framework and demonstrate its utility for both researchers and course instructors by applying it to frame results from interview data on students' use of Taylor approximations.
GENERALIZED STOCHASTIC DURATION IN MARKOVIAN HEATH-JARROW-MORTON FRAMEWORK
Institute of Scientific and Technical Information of China (English)
简志宏; 李楚霖
2002-01-01
This paper focuses on how to measure the interest rate risk. The conventional measure methods of interest rate risk arc reviewed and the duration concept is generalized to stochastic duration in the Markovian HJM framework. The generalized stochastic duration of the coupon bond is defined as the time to maturity of a zero coupon bond having the same instantaneous variance as the coupon bond. According to this definition, the authors first present the framework of Markovian HJM model, then deduce the measures of stochastic duration in some special cases which cover some extant interest term structure.
GEMFsim: A Stochastic Simulator for the Generalized Epidemic Modeling Framework
Sahneh, Faryad Darabi; Shakeri, Heman; Fan, Futing; Scoglio, Caterina
2016-01-01
The recently proposed generalized epidemic modeling framework (GEMF) \\cite{sahneh2013generalized} lays the groundwork for systematically constructing a broad spectrum of stochastic spreading processes over complex networks. This article builds an algorithm for exact, continuous-time numerical simulation of GEMF-based processes. Moreover the implementation of this algorithm, GEMFsim, is available in popular scientific programming platforms such as MATLAB, R, Python, and C; GEMFsim facilitates simulating stochastic spreading models that fit in GEMF framework. Using these simulations one can examine the accuracy of mean-field-type approximations that are commonly used for analytical study of spreading processes on complex networks.
Generalized Quantum Theory and Mathematical Foundations of Quantum Field Theory
Maroun, Michael Anthony
This dissertation is divided into two main topics. The first is the generalization of quantum dynamics when the Schrodinger partial differential equation is not defined even in the weak mathematical sense because the potential function itself is a distribution in the spatial variable, the same variable that is used to define the kinetic energy operator, i.e. the Laplace operator. The procedure is an extension and broadening of the distributional calculus and offers spectral results as an alternative to the only other two known methods to date, namely a) the functional calculi; and b) non-standard analysis. Furthermore, the generalizations of quantum dynamics presented within give a resolution to the time asymmetry paradox created by multi-particle quantum mechanics due to the time evolution still being unitary. A consequence is the randomization of phases needed for the fundamental justification Pauli master equation. The second topic is foundations of the quantum theory of fields. The title is phrased as ``foundations'' to emphasize that there is no claim of uniqueness but rather a proposal is put forth, which is markedly different than that of constructive or axiomatic field theory. In particular, the space of fields is defined as a space of generalized functions with involutive symmetry maps (the CPT invariance) that affect the topology of the field space. The space of quantum fields is then endowed the Frechet property and interactions change the topology in such a way as to cause some field spaces to be incompatible with others. This is seen in the consequences of the Haag theorem. Various examples and discussions are given that elucidate a new view of the quantum theory of fields and its (lack of) mathematical structure.
On ASGS framework: general requirements and an example of implementation
Institute of Scientific and Technical Information of China (English)
KULESZA Kamil; KOTULSKI Zbigniew
2007-01-01
In the paper we propose a general, abstract framework for Automatic Secret Generation and Sharing (ASGS) that should be independent of underlying Secret Sharing Scheme (SSS). ASGS allows to prevent the Dealer from knowing the secret.The Basic Property Conjecture (BPC) forms the base of the framework. Due to the level of abstraction, results are portable into the realm of quantum computing.Two situations are discussed. First concerns simultaneous generation and sharing of the random, prior nonexistent secret.Such a secret remains unknown until it is reconstructed. Next, we propose the framework for automatic sharing of a known secret.In this case the Dealer does not know the secret and the secret Owner does not know the shares. We present opportunities for joining ASGS with other extended capabilities, with special emphasis on PVSS and pre-positioned secret sharing. Finally, we illustrate framework with practical implementation.
A Heuristic Framework to Solve a General Delivery Problem
Lian, Lian; Castelain, Emmanuel
2010-06-01
This paper presents a new distribution and route planning problem, General Delivery Problem (GDP) which is more general than the well-known Vehicle Routing Problem. To solve a GDP, a three-phase framework heuristic approach based on decomposition techniques is introduced. The decomposition techniques are employed to divide an original problem into a set of sub-problems, which can reduce the problem size. A kind of decomposition technique, Capacity Clustering Algorithm (CCA), is embedded into the framework with Simulated Annealing (SA) to solve a special GDP. The proposed three-phase framework with the above two algorithms is compared with five other decomposition methods in a distribution instance of the Regional Fire and Emergency Center in the north of France.
General Object-oriented Framework for Iterative Optimization Algorithms
Mornar, Vedran; Vanjak, Zvonimir
2001-01-01
It is usually impossible to exactly solve the hard optimization problems. One is thus directed to iterative algorithms. In implementation of these iterative algorithms, some common characteristics can be observed, which can be generalized in an object-oriented framework. This can significantly reduce the time needed for implementation of an iterative algorithm.
The relationship between learning mathematics and general cognitive ability in primary school.
Cowan, Richard; Hurry, Jane; Midouhas, Emily
2017-08-12
Three relationships between learning mathematics and general cognitive ability have been hypothesized: The educational hypothesis that learning mathematics develops general cognitive skills, the psychometric hypothesis that differences in general cognitive ability cause differences in mathematical attainment, and the reciprocal influence hypothesis that developments in mathematical ability and general cognitive ability influence each other. These hypotheses are assessed with a sample of 948 children from the Twins Early Development Study who were assessed at 7, 9, and 10 years on mathematics, English, and general cognitive ability. A cross-lagged path analysis with mathematics and general cognitive ability measures supports the reciprocal influence hypothesis between 7 and 9 and between 9 and 10. A second analysis including English assessments only provides evidence of a reciprocal relationship between 7 and 9. Statement of Contribution What is already known on this subject? The correlations between mathematical attainment, literacy, and measures of general cognitive skills are well established. The role of literacy in developing general cognitive skills is emerging. What the present study adds? Mathematics contributes to the development of general cognitive skills. General cognitive ability contributes to mathematical development between 7 and 10. These findings support the hypothesis of reciprocal influence between mathematics and general cognitive ability, at least between 7 and 9. © 2017 The British Psychological Society.
ACER: An Analytic Framework for Students' Use of Mathematics in Upper-Division Physics
Wilcox, Bethany R; Rehn, Daniel A; Pollock, Steven J
2013-01-01
Many students in upper-division physics courses struggle with the mathematically sophisticated tools and techniques that are required for advanced physics content. We have developed an analytical framework to assist instructors and researchers in characterizing students' difficulties with specific mathematical tools when solving the long and complex problems that are characteristic of upper-division. In this paper, we present this framework, including its motivation and development. We also describe an application of the framework to investigations of student difficulties with direct integration in electricity and magnetism (i.e., Coulomb's Law) and approximation methods in classical mechanics (i.e., Taylor series). These investigations provide examples of the types of difficulties encountered by advanced physics students, as well as the utility of the framework for both researchers and instructors.
Analytic framework for students' use of mathematics in upper-division physics
Wilcox, Bethany R.; Caballero, Marcos D.; Rehn, Daniel A.; Pollock, Steven J.
2013-12-01
Many students in upper-division physics courses struggle with the mathematically sophisticated tools and techniques that are required for advanced physics content. We have developed an analytical framework to assist instructors and researchers in characterizing students’ difficulties with specific mathematical tools when solving the long and complex problems that are characteristic of upper division. In this paper, we present this framework, including its motivation and development. We also describe an application of the framework to investigations of student difficulties with direct integration in electricity and magnetism (i.e., Coulomb’s law) and approximation methods in classical mechanics (i.e., Taylor series). These investigations provide examples of the types of difficulties encountered by advanced physics students, as well as the utility of the framework for both researchers and instructors.
A Generalized Framework for Auto-tuning Stencil Computations
Energy Technology Data Exchange (ETDEWEB)
Kamil, Shoaib; Chan, Cy; Williams, Samuel; Oliker, Leonid; Shalf, John; Howison, Mark; Bethel, E. Wes; Prabhat,
2009-05-01
This work introduces a generalized framework for automatically tuning stencil computations to achieve superior performance on a broad range of multicore architectures. Stencil (nearest-neighbor) based kernels constitute the core of many important scientific applications involving block-structured grids. Auto-tuning systems search over optimization strategies to find the combination of tunable parameters that maximizes computational efficiency for a given algorithmic kernel. Although the auto-tuning strategy has been successfully applied to libraries, generalized stencil kernels are not amenable to packaging as libraries. Studied kernels in this work include both memory-bound kernels as well as a computation-bound bilateral filtering kernel. We introduce a generalized stencil auto-tuning framework that takes a straightforward Fortran expression of a stencil kernel and automatically generates tuned implementations of the kernel in C or Fortran to achieve performance portability across diverse computer architectures.
Higgins, C. W.; Abou Najm, M.
2015-12-01
Water, energy, and agriculture depend on each other so strongly that attempts to achieve sustainability in any of those three domains will directly impact the others. These interdependencies, collectively known as the Water-Energy-Food Nexus, become more complex and more critical as the climate changes, the population grows, habits and lifestyle alternatives, and the prices of water, energy, and food increase. The U.S. National Intelligence Council has identified the nexus of water, energy, food, and climate change as one of four overarching megatrends that will shape the world in 2030. However, the global research community has rarely addressed the full problem and focused instead on different subsets of the problem. For example, interactions between two of the three domains were studied, often neglecting the impact of such interaction on the third domain. Investigators have quantified water-energy tradeoffs in the highly engineered, centralized systems of water and power management. Agricultural researchers have tracked water costs by applying the concept of virtual water (the total volume of water needed to produce and process a commodity or service) or using large-scale system models to investigate food and water security. Integrative nexus initiatives have focused on reviews and data collection of existing knowledge and relevant facts. They unfortunately lack a conceptual and mathematical framework that can integrate all the gathered knowledge and account for multiple interactions, feedbacks, or natural processes that occur across all three domains of the nexus. Here, we present an integrated conceptual and mathematical framework (roadmap) for the nexus. This framework is driven by spatiotemporal demands for water, energy, and food to be satisfied by resource management of the three domains, envisioned as a stepwise process, with each step requiring inputs from the three nexus domains and creating waste products. The efficiency of each step, combined with mass
Motivation and engagement in mathematics: a qualitative framework for teacher-student interactions
Durksen, Tracy L.; Way, Jennifer; Bobis, Janette; Anderson, Judy; Skilling, Karen; Martin, Andrew J.
2017-02-01
We started with a classic research question (How do teachers motivate and engage middle year students in mathematics?) that is solidly underpinned and guided by an integration of two theoretical and multidimensional models. In particular, the current study illustrates how theory is important for guiding qualitative analytical approaches to motivation and engagement in mathematics. With little research on how teachers of mathematics are able to maintain high levels of student motivation and engagement, we focused on developing a qualitative framework that highlights the influence of teacher-student interactions. Participants were six teachers (upper primary and secondary) that taught students with higher-than-average levels of motivation and engagement in mathematics. Data sources included one video-recorded lesson and associated transcripts from pre- and post-lesson interviews with each teacher. Overall, effective classroom organisation stood out as a priority when promoting motivation and engagement in mathematics. Results on classroom organisation revealed four key indicators within teacher-student interactions deemed important for motivation and engagement in mathematics—confidence, climate, contact, and connection. Since much of the effect of teachers on student learning relies on interactions, and given the universal trend of declining mathematical performance during the middle years of schooling, future research and intervention studies might be assisted by our qualitative framework.
Muñiz-Rodríguez, Laura; Alonso, Pedro; Rodríguez-Muñiz, Luis J.; Valcke, Martin
2017-01-01
Initial teacher education programmes provide student teachers with the desired competences to develop themselves as teachers. Although a generic framework for teaching competences is available covering all school subjects in Spain, the initial teacher education programmes curriculum does not specify which competences secondary mathematics student…
Generalized framework for context-specific metabolic model extraction methods
Directory of Open Access Journals (Sweden)
Semidán eRobaina Estévez
2014-09-01
Full Text Available Genome-scale metabolic models are increasingly applied to investigate the physiology not only of simple prokaryotes, but also eukaryotes, such as plants, characterized with compartmentalized cells of multiple types. While genome-scale models aim at including the entirety of known metabolic reactions, mounting evidence has indicated that only a subset of these reactions is active in a given context, including: developmental stage, cell type, or environment. As a result, several methods have been proposed to reconstruct context-specific models from existing genome-scale models by integrating various types of high-throughput data. Here we present a mathematical framework that puts all existing methods under one umbrella and provides the means to better understand their functioning, highlight similarities and differences, and to help users in selecting a most suitable method for an application.
A General Framework for Structured Sparsity via Proximal Optimization
Argyriou, Andreas; Morales, Jean; Pontil, Massimiliano
2011-01-01
We study a generalized framework for structured sparsity. It extends the well-known methods of Lasso and Group Lasso by incorporating additional constraints on the variables as part of a convex optimization problem. This framework provides a straightforward way of favouring prescribed sparsity patterns, such as orderings, contiguous regions and overlapping groups, among others. Existing optimization methods are limited to specific constraint sets and tend to not scale well with sample size and dimensionality. We propose a novel first order proximal method, which builds upon results on fixed points and successive approximations. The algorithm can be applied to a general class of conic and norm constraints sets and relies on a proximity operator subproblem which can be computed explicitly. Experiments on different regression problems demonstrate the efficiency of the optimization algorithm and its scalability with the size of the problem. They also demonstrate state of the art statistical performance, which imp...
Thermodynamic framework for a generalized heat transport equation
Directory of Open Access Journals (Sweden)
Guo Yangyu
2016-06-01
Full Text Available In this paper, a generalized heat transport equation including relaxational, nonlocal and nonlinear effects is provided, which contains diverse previous phenomenological models as particular cases. The aim of the present work is to establish an extended irreversible thermodynamic framework, with generalized expressions of entropy and entropy flux. Nonlinear thermodynamic force-flux relation is proposed as an extension of the usual linear one, giving rise to the nonlinear terms in the heat transport equation and ensuring compatibility with the second law. Several previous results are recovered in the linear case, and some additional results related to nonlinear terms are also obtained.
Alignment between South African mathematics assessment standards and the TIMSS assessment frameworks
Directory of Open Access Journals (Sweden)
Mdutshekelwa Ndlovu
2012-10-01
Full Text Available South Africa’s performance in international benchmark tests is a major cause for concern amongst educators and policymakers, raising questions about the effectiveness of the curriculum reform efforts of the democratic era. The purpose of the study reported in this article was to investigate the degree of alignment between the TIMSS 2003 Grade 8 Mathematics assessment frameworks and the Revised National Curriculum Statements (RNCS assessment standards for Grade 8 Mathematics, later revised to become the Curriculum and Assessment Policy Statements (CAPS. Such an investigation could help to partly shed light on why South African learners do not perform well and point out discrepancies that need to be attended to. The methodology of document analysis was adopted for the study, with the RNCS and the TIMSS 2003 Grade 8 Mathematics frameworks forming the principal documents. Porter’s moderately complex index of alignment was adopted for its simplicity. The computed index of 0.751 for the alignment between the RNCS assessment standards and the TIMSS assessment objectives was found to be significantly statistically low, at the alpha level of 0.05, according to Fulmer’s critical values for 20 cells and 90 or 120 standard points. The study suggests that inadequate attention has been paid to the alignment of the South African mathematics curriculum to the successive TIMSS assessment frameworks in terms of the cognitive level descriptions. The study recommends that participation in TIMSS should rigorously and critically inform ongoing curriculum reform efforts.
A Generalized Cauchy Distribution Framework for Problems Requiring Robust Behavior
Carrillo, Rafael E.; Aysal, Tuncer C.; Barner, Kenneth E.
2010-12-01
Statistical modeling is at the heart of many engineering problems. The importance of statistical modeling emanates not only from the desire to accurately characterize stochastic events, but also from the fact that distributions are the central models utilized to derive sample processing theories and methods. The generalized Cauchy distribution (GCD) family has a closed-form pdf expression across the whole family as well as algebraic tails, which makes it suitable for modeling many real-life impulsive processes. This paper develops a GCD theory-based approach that allows challenging problems to be formulated in a robust fashion. Notably, the proposed framework subsumes generalized Gaussian distribution (GGD) family-based developments, thereby guaranteeing performance improvements over traditional GCD-based problem formulation techniques. This robust framework can be adapted to a variety of applications in signal processing. As examples, we formulate four practical applications under this framework: (1) filtering for power line communications, (2) estimation in sensor networks with noisy channels, (3) reconstruction methods for compressed sensing, and (4) fuzzy clustering.
A Generalized Cauchy Distribution Framework for Problems Requiring Robust Behavior
Directory of Open Access Journals (Sweden)
Carrillo RafaelE
2010-01-01
Full Text Available Statistical modeling is at the heart of many engineering problems. The importance of statistical modeling emanates not only from the desire to accurately characterize stochastic events, but also from the fact that distributions are the central models utilized to derive sample processing theories and methods. The generalized Cauchy distribution (GCD family has a closed-form pdf expression across the whole family as well as algebraic tails, which makes it suitable for modeling many real-life impulsive processes. This paper develops a GCD theory-based approach that allows challenging problems to be formulated in a robust fashion. Notably, the proposed framework subsumes generalized Gaussian distribution (GGD family-based developments, thereby guaranteeing performance improvements over traditional GCD-based problem formulation techniques. This robust framework can be adapted to a variety of applications in signal processing. As examples, we formulate four practical applications under this framework: (1 filtering for power line communications, (2 estimation in sensor networks with noisy channels, (3 reconstruction methods for compressed sensing, and (4 fuzzy clustering.
GEO label: The General Framework for Labeling and Certification
Bye, B. L.; McCallum, I.; Maso, J.
2012-04-01
The Group on Earth Observations (GEO) is coordinating efforts to build a Global Earth Observation System of Systems, or GEOSS. As part of a strategy to increase the involvement of the science and technology community in GEOSS, both as users and developers of GEOSS itself, GEO decided to develop a GEO label concept related to the scientific relevance, quality, acceptance and societal needs for services and data sets of GEOSS. The development of a GEO label is included in the GEO work plan and several projects address the challenges of developing a GEO label concept. Within the different projects developing the GEO label, various perspectives and approaches are being applied. In order to arrive at a generally accepted GEO label concept, a common understanding and basic knowledge of labeling is necessary. Assessment of quality of internationally standardized Earth observation data products implies possible certification. A general understanding of the framework for international standards and certification will also contribute to a more coherent discussion and more efficient development of a GEO label. We will describe the general labeling and certification framework emphasizing the relation to the three elements of the GEO label: quality, user acceptance and relevance. Based on a survey of international labels done by the EGIDA project, we have analyzed the legal framework and organization of labels and certification. We will discuss the frameworks for certification, user ratings, registration and analysis of user requirements. Quality assessment is a particular focus of the analysis and is based on the work done by the GeoViQua project. A GEO label will function both as a data distribution strategy and as a general management system for data. Through a label users can compare different data sets and get access to more information about the relevant data, including quality. A label will provide traceability of data both in the interest of users as well as data
Energy Technology Data Exchange (ETDEWEB)
Stakhov, A.P. [International Club of the Golden Section, 6 McCreary Trail, Bolton, ON, L7E 2C8 (Canada)] e-mail: goldenmuseum@rogers.com
2005-10-01
The 'Dichotomy Principle' and the classical 'Golden Section Principle' are two of the most important principles of Nature, Science and also Art. The Generalized Principle of the Golden Section that follows from studying the diagonal sums of the Pascal triangle is a sweeping generalization of these important principles. This underlies the foundation of 'Harmony Mathematics', a new proposed mathematical direction. Harmony Mathematics includes a number of new mathematical theories: an algorithmic measurement theory, a new number theory, a new theory of hyperbolic functions based on Fibonacci and Lucas numbers, and a theory of the Fibonacci and 'Golden' matrices. These mathematical theories are the source of many new ideas in mathematics, philosophy, botanic and biology, electrical and computer science and engineering, communication systems, mathematical education as well as theoretical physics and physics of high energy particles.
Speed of Information Processing in Generally Gifted and Excelling-in-Mathematics Adolescents
Paz-Baruch, N.; Leikin, M.; Aharon-Peretz, J.; Leikin, R.
2014-01-01
A considerable amount of recent evidence suggests that speed of information processing (SIP) may be related to general giftedness as well as contributing to higher mathematical ability. To date, no study has examined SIP associated with both general giftedness (G) and excellence in mathematics (EM). This paper presents a part of more extensive…
A mathematical framework for critical transitions: normal forms, variance and applications
Kuehn, Christian
2011-01-01
Critical transitions occur in a wide variety of applications including mathematical biology, climate change, human physiology and economics. A dynamical system that was in a stable state suddenly changes to a distant attractor. Therefore it is highly desirable to find early-warning signs for these critical transitions. Although several different approaches have been proposed for specific models, a detailed mathematical theory has not been developed yet. In this paper we provide another building block of this theory beyond the first results developed in [C. Kuehn. "A mathematical framework for critical transitions: bifurcations, fast-slow systems and stochastic dynamics", submitted, 2010]. We start from classical bifurcation theory and normal forms to classify critical transitions. Using this approach, we proceed to stochastic fluctuations and provided detailed scaling laws of the variance of stochastic sample paths near critical transitions. To show that our theory naturally extends bifurcation theory we appl...
An initial framework for the language of higher-order thinking mathematics practices
Staples, Megan E.; Truxaw, Mary P.
2012-09-01
This article presents an examination of the language demands of cognitively demanding tasks and proposes an initial framework for the language demands of higher-order mathematics thinking practices. We articulate four categories for this framework: language of generalisation, language of comparison, language of proportional reasoning, and language of analysing impact. These categories were developed out of our collaborative work to design and implement higher-order thinking tasks with a group of Grade 9 (14- and 15-year-olds) teachers teaching in a linguistically diverse setting; analyses of student work samples on these tasks; and our knowledge of the literature. We describe each type of language demand and then analyse student work in each category to reveal linguistic challenges facing students as they engage these mathematical tasks. Implications for teaching and professional development are discussed.
A general modular framework for gene set enrichment analysis
Directory of Open Access Journals (Sweden)
Strimmer Korbinian
2009-02-01
Full Text Available Abstract Background Analysis of microarray and other high-throughput data on the basis of gene sets, rather than individual genes, is becoming more important in genomic studies. Correspondingly, a large number of statistical approaches for detecting gene set enrichment have been proposed, but both the interrelations and the relative performance of the various methods are still very much unclear. Results We conduct an extensive survey of statistical approaches for gene set analysis and identify a common modular structure underlying most published methods. Based on this finding we propose a general framework for detecting gene set enrichment. This framework provides a meta-theory of gene set analysis that not only helps to gain a better understanding of the relative merits of each embedded approach but also facilitates a principled comparison and offers insights into the relative interplay of the methods. Conclusion We use this framework to conduct a computer simulation comparing 261 different variants of gene set enrichment procedures and to analyze two experimental data sets. Based on the results we offer recommendations for best practices regarding the choice of effective procedures for gene set enrichment analysis.
Generalized Framework for Similarity Measure of Time Series
Directory of Open Access Journals (Sweden)
Hongsheng Yin
2014-01-01
Full Text Available Currently, there is no definitive and uniform description for the similarity of time series, which results in difficulties for relevant research on this topic. In this paper, we propose a generalized framework to measure the similarity of time series. In this generalized framework, whether the time series is univariable or multivariable, and linear transformed or nonlinear transformed, the similarity of time series is uniformly defined using norms of vectors or matrices. The definitions of the similarity of time series in the original space and the transformed space are proved to be equivalent. Furthermore, we also extend the theory on similarity of univariable time series to multivariable time series. We present some experimental results on published time series datasets tested with the proposed similarity measure function of time series. Through the proofs and experiments, it can be claimed that the similarity measure functions of linear multivariable time series based on the norm distance of covariance matrix and nonlinear multivariable time series based on kernel function are reasonable and practical.
Fundamental Limits of Wideband Localization - Part I: A General Framework
Shen, Yuan
2010-01-01
The availability of positional information is of great importance in many commercial, public safety, and military applications. The coming years will see the emergence of location-aware networks with sub-meter accuracy, relying on accurate range measurements provided by wide bandwidth transmissions. In this two-part paper, we determine the fundamental limits of localization accuracy of wideband wireless networks in harsh multipath environments. We first develop a general framework to characterize the localization accuracy of a given node here and then extend our analysis to cooperative location-aware networks in Part II. In this paper, we characterize localization accuracy in terms of a performance measure called the squared position error bound (SPEB), and introduce the notion of equivalent Fisher information to derive the SPEB in a succinct expression. This methodology provides insights into the essence of the localization problem by unifying localization information from individual anchors and information ...
The Mathematics Value Inventory for General Education Students: Development and Initial Validation
Luttrell, Vickie R.; Callen, Bruce W.; Allen, Charles S.; Wood, Mark D.; Deeds, Donald G.; Richard, David C. S.
2010-01-01
The goal of this study was to develop a self-report inventory that measures individual differences in the perceived value of mathematical literacy for general education students. The Mathematics Value Inventory (MVI) is grounded in the Eccles et al. model of achievement-related choices and surveys students' beliefs in four areas: interest, general…
Lindsey, Jacqueline
2012-01-01
The primary focus of this study was to examine the attitudes of the secondary mathematics teachers toward the inclusion of students with learning disabilities in the general mathematics classroom. Specifically, this study was concerned with the influence of selected demographic variables and school variables on the attitudes of secondary…
A Mathematical Framework for the Analysis of Cyber-Resilient Control Systems
Energy Technology Data Exchange (ETDEWEB)
Melin, Alexander M [ORNL; Ferragut, Erik M [ORNL; Laska, Jason A [ORNL; Fugate, David L [ORNL; Kisner, Roger [ORNL
2013-01-01
The increasingly recognized vulnerability of industrial control systems to cyber-attacks has inspired a considerable amount of research into techniques for cyber-resilient control systems. The majority of this effort involves the application of well known information security (IT) techniques to control system networks. While these efforts are important to protect the control systems that operate critical infrastructure, they are never perfectly effective. Little research has focused on the design of closed-loop dynamics that are resilient to cyber-attack. The majority of control system protection measures are concerned with how to prevent unauthorized access and protect data integrity. We believe that the ability to analyze how an attacker can effect the closed loop dynamics of a control system configuration once they have access is just as important to the overall security of a control system. To begin to analyze this problem, consistent mathematical definitions of concepts within resilient control need to be established so that a mathematical analysis of the vulnerabilities and resiliencies of a particular control system design methodology and configuration can be made. In this paper, we propose rigorous definitions for state awareness, operational normalcy, and resiliency as they relate to control systems. We will also discuss some mathematical consequences that arise from the proposed definitions. The goal is to begin to develop a mathematical framework and testable conditions for resiliency that can be used to build a sound theoretical foundation for resilient control research.
Energy Technology Data Exchange (ETDEWEB)
Shadid, John Nicolas; Lehoucq, Richard B.; Christon, Mark Allen; Slepoy, Alexander; Bochev, Pavel Blagoveston; Collis, Samuel Scott; Wagner, Gregory John
2004-05-01
Existing approaches in multiscale science and engineering have evolved from a range of ideas and solutions that are reflective of their original problem domains. As a result, research in multiscale science has followed widely diverse and disjoint paths, which presents a barrier to cross pollination of ideas and application of methods outside their application domains. The status of the research environment calls for an abstract mathematical framework that can provide a common language to formulate and analyze multiscale problems across a range of scientific and engineering disciplines. In such a framework, critical common issues arising in multiscale problems can be identified, explored and characterized in an abstract setting. This type of overarching approach would allow categorization and clarification of existing models and approximations in a landscape of seemingly disjoint, mutually exclusive and ad hoc methods. More importantly, such an approach can provide context for both the development of new techniques and their critical examination. As with any new mathematical framework, it is necessary to demonstrate its viability on problems of practical importance. At Sandia, lab-centric, prototype application problems in fluid mechanics, reacting flows, magnetohydrodynamics (MHD), shock hydrodynamics and materials science span an important subset of DOE Office of Science applications and form an ideal proving ground for new approaches in multiscale science.
Energy Technology Data Exchange (ETDEWEB)
Wagner, Gregory John (Sandia National Laboratories, Livermore, CA); Collis, Samuel Scott; Templeton, Jeremy Alan (Sandia National Laboratories, Livermore, CA); Lehoucq, Richard B.; Parks, Michael L.; Jones, Reese E. (Sandia National Laboratories, Livermore, CA); Silling, Stewart Andrew; Scovazzi, Guglielmo; Bochev, Pavel B.
2007-10-01
This report is a collection of documents written as part of the Laboratory Directed Research and Development (LDRD) project A Mathematical Framework for Multiscale Science and Engineering: The Variational Multiscale Method and Interscale Transfer Operators. We present developments in two categories of multiscale mathematics and analysis. The first, continuum-to-continuum (CtC) multiscale, includes problems that allow application of the same continuum model at all scales with the primary barrier to simulation being computing resources. The second, atomistic-to-continuum (AtC) multiscale, represents applications where detailed physics at the atomistic or molecular level must be simulated to resolve the small scales, but the effect on and coupling to the continuum level is frequently unclear.
Courses on the Beauty of Mathematics: Our Version of General Education Mathematics Courses
Rash, Agnes M.; Fillebrown, Sandra
2016-01-01
This article describes various courses designed to incorporate mathematical proofs into courses for non-math and non-science majors. These courses, nicknamed "math beauty" courses, are designed to discuss one topic in-depth rather than to introduce many topics at a superficial level. A variety of courses, each requiring students to…
Developing a General Framework for Human Autonomy Teaming
Lachter, Joel; Brandt, Summer; Shively, Jay
2017-01-01
Automation has entered nearly every aspect of our lives, but it often remains hard to understand. Why is this? Automation is often brittle, requiring constant human oversight to assure it operates as intended. This oversight has become harder as automation has become more complicated. To resolve this problem, Human-Autonomy Teaming (HAT) has been proposed. HAT looks to make automation act as more of a teammate, by having it communicate with human operators in a more human, goal-directed, manner which provides transparency into the reasoning behind automated recommendations and actions. This, in turn, permits more trust in the automation when it is appropriate, and less when it is not, allowing a more targeted supervision of automated functions. This paper proposes a framework for HAT, incorporating two key tenets: bi-directional communication, and operator directed authority. We have successfully applied these tenets to integrating the autonomous constrained flight planner (an aide for planning diverts) into a dispatch station. We propose the development of general design patterns that may allow these results to be generalized to domains such as photography and automotive navigation. While these domains are very different, we find application of our HAT tenets provides a number of opportunities for improving interaction between human operators and automation.
DEFF Research Database (Denmark)
Nørgård, Christian; Roemer, Daniel Beck; Bech, Michael Møller;
2015-01-01
A prototype of a fast switching valve designed for a digital hydraulic transmission has been manufactured and experimentally tested. The valve is an annular seat valve composed of a plunger connected with a direct electromagnetic moving coil actuator as the force producing element. Based...... on an elaborate optimization method the valve is designed to maximize the efficiency of a digital hydraulic motor targeted to a wind turbine transmission system. The optimisation method comprises a mathematical framework which predicts a valve switching time of approximately 1 ms with a peak actuator input power...
Towards a general framework for including noise impacts in LCA.
Cucurachi, Stefano; Heijungs, Reinout; Ohlau, Katrin
epidemiological findings from an LCA perspective and identify areas still missing dose-response relations. A short review of the state-of-science in the field of noise and LCA is presented with an expansion to other contributions in the field subsequent to the comprehensive work by Althaus et al. (2009a; 2009b). Focusing on the analogy between toxicological analysis of pollutants and noise impact evaluation, an alternative approach is suggested, which is oriented to the consideration of any type of noise in LCA and not solely of transportation noise. A multi-step framework is presented as a method for the inclusion of noise impacts on human health in LCA. A theoretical structural framework for the inclusion of noise impacts in LCA is provided as a basis for future modelling expansions in the field. Rather than evaluating traffic/transportation noise, the method focuses on the consideration of the noise level and its impact on human health, regardless of the source producing the noise in an analogous manner as considered in the fields of toxicology and common noise evaluation practices combined. The resulting framework will constitute the basis for the development of a more detailed mathematical model for the inclusion of noise in LCA. The toxicological background and the experience of the analysis of the release of chemicals in LCA seem to provide sufficient ground for the inclusion of noise in LCA: taken into account the physical differences and the uniqueness of noise as an impact, the procedure applied to the release of chemicals during a product life cycle is key for a valuable inclusion of noise in the LCA logic. It is fundamental for the development of research in the field of LCA and noise to consider any type of noise. Further studies are needed to contribute to the inclusion of noise sources and noise impacts in LCA. In this paper, a structure is proposed that will be expanded and adapted in the future and which forms the basic framework for the successive modelling
Zandieh, Michelle; Rasmussen, Chris
2010-01-01
The purpose of this paper is to further the notion of defining as a mathematical activity by elaborating a framework that structures the role of defining in student progress from informal to more formal ways of reasoning. The framework is the result of a retrospective account of a significant learning experience that occurred in an undergraduate…
A general framework for ion equilibrium calculations in compacted bentonite
Birgersson, Martin
2017-03-01
An approach for treating chemical equilibrium between compacted bentonite and aqueous solutions is presented. The treatment is based on conceptualizing bentonite as a homogeneous mixture of water and montmorillonite, and assumes Gibbs-Donnan membrane equilibrium across interfaces to external solutions. An equation for calculating the electrostatic potential difference between bentonite and external solution (Donnan potential) is derived and solved analytically for some simple systems. The solutions are furthermore analyzed in order to illuminate the general mechanisms of ion equilibrium and their relation to measurable quantities. A method is suggested for estimating interlayer activity coefficients based on the notion of an interlayer ionic strength. Using this method, several applications of the framework are presented, giving a set of quantitative predictions which may be relatively simply tested experimentally, e.g.: (1) the relative amount of anions entering the bentonite depends approximately on the square-root of the external concentration for a 1:2 salt (e.g. CaCl2). For a 1:1 salt (e.g. NaCl) the dependence is approximately linear, and for a 1:2 salt (e.g. Na2SO4) the dependence is approximately quadratic. (2) Bentonite contains substantially more nitrate as compared to chloride if equilibrated with the two salt solutions at equal external concentration. (3) Potassium bentonite generally contains more anions as compared to sodium bentonite if equilibrated at the same external concentration. (4) The anion concentration ratio in two bentonite samples of different cations (but with the same density and cation exchange capacity) resembles the ion exchange selectivity coefficient for that specific cation pair. The results show that an adequate treatment of chemical equilibrium between interlayers and bulk solutions are essential when modeling compacted bentonite, and that activity corrections generally are required for relevant ion equilibrium calculations. It
General Framework for Meta-Analysis of Haplotype Association Tests.
Wang, Shuai; Zhao, Jing Hua; An, Ping; Guo, Xiuqing; Jensen, Richard A; Marten, Jonathan; Huffman, Jennifer E; Meidtner, Karina; Boeing, Heiner; Campbell, Archie; Rice, Kenneth M; Scott, Robert A; Yao, Jie; Schulze, Matthias B; Wareham, Nicholas J; Borecki, Ingrid B; Province, Michael A; Rotter, Jerome I; Hayward, Caroline; Goodarzi, Mark O; Meigs, James B; Dupuis, Josée
2016-04-01
For complex traits, most associated single nucleotide variants (SNV) discovered to date have a small effect, and detection of association is only possible with large sample sizes. Because of patient confidentiality concerns, it is often not possible to pool genetic data from multiple cohorts, and meta-analysis has emerged as the method of choice to combine results from multiple studies. Many meta-analysis methods are available for single SNV analyses. As new approaches allow the capture of low frequency and rare genetic variation, it is of interest to jointly consider multiple variants to improve power. However, for the analysis of haplotypes formed by multiple SNVs, meta-analysis remains a challenge, because different haplotypes may be observed across studies. We propose a two-stage meta-analysis approach to combine haplotype analysis results. In the first stage, each cohort estimate haplotype effect sizes in a regression framework, accounting for relatedness among observations if appropriate. For the second stage, we use a multivariate generalized least square meta-analysis approach to combine haplotype effect estimates from multiple cohorts. Haplotype-specific association tests and a global test of independence between haplotypes and traits are obtained within our framework. We demonstrate through simulation studies that we control the type-I error rate, and our approach is more powerful than inverse variance weighted meta-analysis of single SNV analysis when haplotype effects are present. We replicate a published haplotype association between fasting glucose-associated locus (G6PC2) and fasting glucose in seven studies from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium and we provide more precise haplotype effect estimates.
Unified Mathematical Framework for Slicing and Symmetry Reduction over Event Structures
Directory of Open Access Journals (Sweden)
Xinyan Gao
2014-01-01
Full Text Available Nonclassical slicing and symmetry reduction can act as efficient structural abstract methods for pruning state space when dealing with verification problems. In this paper, we mainly address theoretical and algorithmic aspects for nonclassical slicing and symmetry reduction over prime event structures. We propose sliced and symmetric quotient reduction models of event structures and present their corresponding algorithms. To construct the underlying foundation of the proposed methodologies, we introduce strong and weak conflict concepts and a pair of mutually inverse operators and extend permutation group based symmetry notion of event structures. We have established a unified mathematical framework for slicing and symmetry reduction, and further investigated the translation, isomorphism, and equivalence relationship and other related basic facts from a theoretical point of view. The framework may provide useful guidance and theoretical exploration for overcoming verification challenges. This paper also demonstrates their practical applications by two cases.
Deep graphs—A general framework to represent and analyze heterogeneous complex systems across scales
Traxl, Dominik; Boers, Niklas; Kurths, Jürgen
2016-06-01
Network theory has proven to be a powerful tool in describing and analyzing systems by modelling the relations between their constituent objects. Particularly in recent years, a great progress has been made by augmenting "traditional" network theory in order to account for the multiplex nature of many networks, multiple types of connections between objects, the time-evolution of networks, networks of networks and other intricacies. However, existing network representations still lack crucial features in order to serve as a general data analysis tool. These include, most importantly, an explicit association of information with possibly heterogeneous types of objects and relations, and a conclusive representation of the properties of groups of nodes as well as the interactions between such groups on different scales. In this paper, we introduce a collection of definitions resulting in a framework that, on the one hand, entails and unifies existing network representations (e.g., network of networks and multilayer networks), and on the other hand, generalizes and extends them by incorporating the above features. To implement these features, we first specify the nodes and edges of a finite graph as sets of properties (which are permitted to be arbitrary mathematical objects). Second, the mathematical concept of partition lattices is transferred to the network theory in order to demonstrate how partitioning the node and edge set of a graph into supernodes and superedges allows us to aggregate, compute, and allocate information on and between arbitrary groups of nodes. The derived partition lattice of a graph, which we denote by deep graph, constitutes a concise, yet comprehensive representation that enables the expression and analysis of heterogeneous properties, relations, and interactions on all scales of a complex system in a self-contained manner. Furthermore, to be able to utilize existing network-based methods and models, we derive different representations of
Traxl, Dominik; Boers, Niklas; Kurths, Jürgen
2016-06-01
Network theory has proven to be a powerful tool in describing and analyzing systems by modelling the relations between their constituent objects. Particularly in recent years, a great progress has been made by augmenting "traditional" network theory in order to account for the multiplex nature of many networks, multiple types of connections between objects, the time-evolution of networks, networks of networks and other intricacies. However, existing network representations still lack crucial features in order to serve as a general data analysis tool. These include, most importantly, an explicit association of information with possibly heterogeneous types of objects and relations, and a conclusive representation of the properties of groups of nodes as well as the interactions between such groups on different scales. In this paper, we introduce a collection of definitions resulting in a framework that, on the one hand, entails and unifies existing network representations (e.g., network of networks and multilayer networks), and on the other hand, generalizes and extends them by incorporating the above features. To implement these features, we first specify the nodes and edges of a finite graph as sets of properties (which are permitted to be arbitrary mathematical objects). Second, the mathematical concept of partition lattices is transferred to the network theory in order to demonstrate how partitioning the node and edge set of a graph into supernodes and superedges allows us to aggregate, compute, and allocate information on and between arbitrary groups of nodes. The derived partition lattice of a graph, which we denote by deep graph, constitutes a concise, yet comprehensive representation that enables the expression and analysis of heterogeneous properties, relations, and interactions on all scales of a complex system in a self-contained manner. Furthermore, to be able to utilize existing network-based methods and models, we derive different representations of
Directory of Open Access Journals (Sweden)
Sam Mavandadi
Full Text Available We propose a methodology for digitally fusing diagnostic decisions made by multiple medical experts in order to improve accuracy of diagnosis. Toward this goal, we report an experimental study involving nine experts, where each one was given more than 8,000 digital microscopic images of individual human red blood cells and asked to identify malaria infected cells. The results of this experiment reveal that even highly trained medical experts are not always self-consistent in their diagnostic decisions and that there exists a fair level of disagreement among experts, even for binary decisions (i.e., infected vs. uninfected. To tackle this general medical diagnosis problem, we propose a probabilistic algorithm to fuse the decisions made by trained medical experts to robustly achieve higher levels of accuracy when compared to individual experts making such decisions. By modelling the decisions of experts as a three component mixture model and solving for the underlying parameters using the Expectation Maximisation algorithm, we demonstrate the efficacy of our approach which significantly improves the overall diagnostic accuracy of malaria infected cells. Additionally, we present a mathematical framework for performing 'slide-level' diagnosis by using individual 'cell-level' diagnosis data, shedding more light on the statistical rules that should govern the routine practice in examination of e.g., thin blood smear samples. This framework could be generalized for various other tele-pathology needs, and can be used by trained experts within an efficient tele-medicine platform.
Novikasari, Ifada; Darhim, Didi Suryadi
2015-01-01
This study explored the characteristics of pre-service primary teachers (PSTs) influenced by mathematical belief and mathematical knowledge for teaching (MKT) PSTs'. A qualitative approach was used to investigate the levels of PSTs on mathematical belief and MKT. The two research instruments used in this study were an interview-based task and a…
Novikasari, Ifada; Darhim, Didi Suryadi
2015-01-01
This study explored the characteristics of pre-service primary teachers (PSTs) influenced by mathematical belief and mathematical knowledge for teaching (MKT) PSTs'. A qualitative approach was used to investigate the levels of PSTs on mathematical belief and MKT. The two research instruments used in this study were an interview-based task and a…
RGG: a general GUI Framework for R scripts.
Visne, Ilhami; Dilaveroglu, Erkan; Vierlinger, Klemens; Lauss, Martin; Yildiz, Ahmet; Weinhaeusel, Andreas; Noehammer, Christa; Leisch, Friedrich; Kriegner, Albert
2009-03-02
R is the leading open source statistics software with a vast number of biostatistical and bioinformatical analysis packages. To exploit the advantages of R, extensive scripting/programming skills are required. We have developed a software tool called R GUI Generator (RGG) which enables the easy generation of Graphical User Interfaces (GUIs) for the programming language R by adding a few Extensible Markup Language (XML) - tags. RGG consists of an XML-based GUI definition language and a Java-based GUI engine. GUIs are generated in runtime from defined GUI tags that are embedded into the R script. User-GUI input is returned to the R code and replaces the XML-tags. RGG files can be developed using any text editor. The current version of RGG is available as a stand-alone software (RGGRunner) and as a plug-in for JGR. RGG is a general GUI framework for R that has the potential to introduce R statistics (R packages, built-in functions and scripts) to users with limited programming skills and helps to bridge the gap between R developers and GUI-dependent users. RGG aims to abstract the GUI development from individual GUI toolkits by using an XML-based GUI definition language. Thus RGG can be easily integrated in any software. The RGG project further includes the development of a web-based repository for RGG-GUIs. RGG is an open source project licensed under the Lesser General Public License (LGPL) and can be downloaded freely at (http://rgg.r-forge.r-project.org).
RGG: A general GUI Framework for R scripts
Directory of Open Access Journals (Sweden)
Noehammer Christa
2009-03-01
Full Text Available Abstract Background R is the leading open source statistics software with a vast number of biostatistical and bioinformatical analysis packages. To exploit the advantages of R, extensive scripting/programming skills are required. Results We have developed a software tool called R GUI Generator (RGG which enables the easy generation of Graphical User Interfaces (GUIs for the programming language R by adding a few Extensible Markup Language (XML – tags. RGG consists of an XML-based GUI definition language and a Java-based GUI engine. GUIs are generated in runtime from defined GUI tags that are embedded into the R script. User-GUI input is returned to the R code and replaces the XML-tags. RGG files can be developed using any text editor. The current version of RGG is available as a stand-alone software (RGGRunner and as a plug-in for JGR. Conclusion RGG is a general GUI framework for R that has the potential to introduce R statistics (R packages, built-in functions and scripts to users with limited programming skills and helps to bridge the gap between R developers and GUI-dependent users. RGG aims to abstract the GUI development from individual GUI toolkits by using an XML-based GUI definition language. Thus RGG can be easily integrated in any software. The RGG project further includes the development of a web-based repository for RGG-GUIs. RGG is an open source project licensed under the Lesser General Public License (LGPL and can be downloaded freely at http://rgg.r-forge.r-project.org
Chu, Felicia W; vanMarle, Kristy; Geary, David C
2016-01-01
One hundred children (44 boys) participated in a 3-year longitudinal study of the development of basic quantitative competencies and the relation between these competencies and later mathematics and reading achievement. The children's preliteracy knowledge, intelligence, executive functions, and parental educational background were also assessed. The quantitative tasks assessed a broad range of symbolic and nonsymbolic knowledge and were administered four times across 2 years of preschool. Mathematics achievement was assessed at the end of each of 2 years of preschool, and mathematics and word reading achievement were assessed at the end of kindergarten. Our goals were to determine how domain-general abilities contribute to growth in children's quantitative knowledge and to determine how domain-general and domain-specific abilities contribute to children's preschool mathematics achievement and kindergarten mathematics and reading achievement. We first identified four core quantitative competencies (e.g., knowledge of the cardinal value of number words) that predict later mathematics achievement. The domain-general abilities were then used to predict growth in these competencies across 2 years of preschool, and the combination of domain-general abilities, preliteracy skills, and core quantitative competencies were used to predict mathematics achievement across preschool and mathematics and word reading achievement at the end of kindergarten. Both intelligence and executive functions predicted growth in the four quantitative competencies, especially across the first year of preschool. A combination of domain-general and domain-specific competencies predicted preschoolers' mathematics achievement, with a trend for domain-specific skills to be more strongly related to achievement at the beginning of preschool than at the end of preschool. Preschool preliteracy skills, sensitivity to the relative quantities of collections of objects, and cardinal knowledge predicted
1982-11-01
inversion can be performed on any concept. The biggest departure of this framework from current views is that the ability for abstract thinking does not...preassume the capacity for language. The prerequisites for abstract thinking seem to be only abstraction, generalization, and inversion. The fact that we
McInroe, Benjamin; Astley, Henry; Gong, Chaohui; Kawano, Sandy; Schiebel, Perrin; Choset, Howie; Goldman, Daniel I.
The transition from aquatic to terrestrial life presented new challenges to early walkers, necessitating robust locomotion on complex, flowable substrates (e.g. sand, mud). Locomotion on such substrates is sensitive to limb morphology and kinematics. Although early walker morphologies are known, principles of appendage control remain elusive. To reveal limb control strategies that facilitated the invasion of land, we study both robotic and mathematical models. Robot experiments show that an active tail is critical for robust locomotion on granular media, enabling locomotion even with poor foot placement and limited ability to lift the body. Using a granular resistive force theory model, we construct connection vector fields that reveal how appendage coordination and terrain inclination impact locomotor performance. This model replicates experimental results, showing that moving limbs/tail in phase is most effective (suggesting a locomotor template). Varying limb trajectories and contacts, we find gaits for which tail use can be neutral or harmful, suggesting limb-tail coordination to be a nontrivial aspect of locomotion. Our findings show that robot experiments coupled with geometric mechanics provide a general framework to reveal principles of robust terrestrial locomotion. This work was supported by NSF PoLS.
General overview of the disaster management framework in Cameroon.
Bang, Henry Ngenyam
2014-07-01
Efficient and effective disaster management will prevent many hazardous events from becoming disasters. This paper constitutes the most comprehensive document on the natural disaster management framework of Cameroon. It reviews critically disaster management in Cameroon, examining the various legislative, institutional, and administrative frameworks that help to facilitate the process. Furthermore, it illuminates the vital role that disaster managers at the national, regional, and local level play to ease the process. Using empirical data, the study analyses the efficiency and effectiveness of the actions of disaster managers. Its findings reveal inadequate disaster management policies, poor coordination between disaster management institutions at the national level, the lack of trained disaster managers, a skewed disaster management system, and a top-down hierarchical structure within Cameroon's disaster management framework. By scrutinising the disaster management framework of the country, policy recommendations based on the research findings are made on the institutional and administrative frameworks.
A mathematical framework for probabilistic choice based on information theory and psychophysics.
Takahashi, Taiki
2006-01-01
Risky decision-making (e.g. reward dependency) has been associated with substance abuse, psychopathy and pathological gambling; conversely, marked sensitivity to risk and uncertainty have been observed in anxiety disorder patients. In economic decision theory, probability and uncertainty have been dissociated. Frank Knight defined uncertainty as loss of information on the probability distribution of outcomes for choices (i.e., unpredictability), which is referred to as Knightian uncertainty (also as ambiguity). However, even when the probability distribution of outcomes is known, there are different degrees of predictability. In information theory, this type of degrees of uncertainty/unpredictability has been parametrized by introducing Shannon entropy. In the present paper, we show: (i) a mathematical framework combining Shannon entropy in information theory and Weber's law in psychophysics is capable of parametrizing subject's level of both aversion to probabilistic uncertainty (exaggerated in anxiety disorder patients) and reward dependency (enhanced in drug addicts and pathological gamblers), and (ii) this framework has an analogue in thermodynamics, therefore this can readily be utilized in studies in the nascent fields of neuroeconomics and econophysics as well. Future study directions for elucidating maladaptive personality characteristics in neuropsychiatric patients by using the present framework are discussed.
Ge, Hao; Qian, Hong
2017-01-01
This paper studies a mathematical formalism of nonequilibrium thermodynamics for chemical reaction models with N species, M reactions, and general rate law. We establish a mathematical basis for J. W. Gibbs' macroscopic chemical thermodynamics under G. N. Lewis' kinetic law of entire equilibrium (detailed balance in nonlinear chemical kinetics). In doing so, the equilibrium thermodynamics is then naturally generalized to nonequilibrium settings without detailed balance. The kinetic models are represented by a Markovian jumping process. A generalized macroscopic chemical free energy function and its associated balance equation with nonnegative source and sink are the major discoveries. The proof is based on the large deviation principle of this type of Markov processes. A general fluctuation dissipation theorem for stochastic reaction kinetics is also proved. The mathematical theory illustrates how a novel macroscopic dynamic law can emerges from the mesoscopic kinetics in a multi-scale system.
Einstein's Unification: General Relativity and the Quest for Mathematical Naturalness
van Dongen, J.A.E.F.
2002-01-01
The aim of the thesis has been to understand Einstein's development and see the historical coherence in his later attitude in physics. The lesson we learned has been straightforward: the key that unlocks the later Einstein lies in the road by which he arrived at the field equations of general relati
Einstein's Unification: General Relativity and the Quest for Mathematical Naturalness
van Dongen, J.A.E.F.
2002-01-01
The aim of the thesis has been to understand Einstein's development and see the historical coherence in his later attitude in physics. The lesson we learned has been straightforward: the key that unlocks the later Einstein lies in the road by which he arrived at the field equations of general
Directory of Open Access Journals (Sweden)
E. M. E. Zayed
2014-01-01
Full Text Available We apply the generalized projective Riccati equations method to find the exact traveling wave solutions of some nonlinear evolution equations with any-order nonlinear terms, namely, the nonlinear Pochhammer-Chree equation, the nonlinear Burgers equation and the generalized, nonlinear Zakharov-Kuznetsov equation. This method presents wider applicability for handling many other nonlinear evolution equations in mathematical physics.
Sweller, John; Clark, Richard; Kirschner, Paul A.
2010-01-01
Sweller, J., Clark, R., & Kirschner, P. A. (2010). Teaching general problem-solving skills is not a substitute for, or a viable addition to, teaching mathematics. Notices of the American Mathematical Society, 57, 1303-1304.
Sweller, John; Clark, Richard; Kirschner, Paul A.
2010-01-01
Sweller, J., Clark, R., & Kirschner, P. A. (2010). Teaching general problem-solving skills is not a substitute for, or a viable addition to, teaching mathematics. Notices of the American Mathematical Society, 57, 1303-1304.
General Framework for Evaluating Password Complexity and Strength
2015-11-15
use the inequality of arithmetic and geometric means (AM-GM inequality) [30] to prove this lemma. AM- GM inequality states that the arithmetic mean of...Renyi’s entropy and kernel perspectives. Springer Science & Business Media , 2010. [29] C. E. Shannon, “A mathematical theory of communication,” SIG
Bregman divergence as general framework to estimate unnormalized statistical models
Gutmann, Michael
2012-01-01
We show that the Bregman divergence provides a rich framework to estimate unnormalized statistical models for continuous or discrete random variables, that is, models which do not integrate or sum to one, respectively. We prove that recent estimation methods such as noise-contrastive estimation, ratio matching, and score matching belong to the proposed framework, and explain their interconnection based on supervised learning. Further, we discuss the role of boosting in unsupervised learning.
DEFF Research Database (Denmark)
Nørgård, Christian; Roemer, Daniel Beck; Bech, Michael Møller
2015-01-01
A prototype of a fast switching valve designed for a digital hydraulic transmission has been manufactured and experimentally tested. The valve is an annular seat valve composed of a plunger connected with a direct electromagnetic moving coil actuator as the force producing element. Based on an el......A prototype of a fast switching valve designed for a digital hydraulic transmission has been manufactured and experimentally tested. The valve is an annular seat valve composed of a plunger connected with a direct electromagnetic moving coil actuator as the force producing element. Based...... of 10 kW during switching (mean of approximately 250 W) and a pressure loss below 0.5 bar at 600 l/min. The main goal of this article is validate parts of the mathematical framework based on a series of experiments. Furthermore, this article aims to document the experience gained from the experimental...... work and to study and assess a moving coil actuators suitability for the application....
Contextualizing Concepts using a Mathematical Generalization of the Quantum Formalism
Gabora, L; Gabora, Liane; Aerts, Diederik
2002-01-01
We outline the rationale and preliminary results of using the State Context Property (SCOP) formalism, originally developed as a generalization of quantum mechanics, to describe the contextual manner in which concepts are evoked, used, and combined to generate meaning. The quantum formalism was developed to cope with problems arising in the description of (1) the measurement process, and (2) the generation of new states with new properties when particles become entangled. Similar problems arising with concepts motivated the formal treatment introduced here. Concepts are viewed not as fixed representations, but entities existing in states of potentiality that require interaction with a context--a stimulus or another concept--to 'collapse' to an instantiated form (e.g. exemplar, prototype, or other possibly imaginary instance). The stimulus situation plays the role of the measurement in physics, acting as context that induces a change of the cognitive state from superposition state to collapsed state. The colla...
Demarest, Jack
1987-01-01
Discusses the on-going debate between comparative and behaviorist frameworks in psychology. Advocates a comparative framework and suggests methods to avoid misconceptions about the field. A framework for reorganizing the focus of general psychology and integrating it into a neofunctionalist perspective is included. (DH)
Porter's contribution to more general and dynamic strategy frameworks
F.A.J. van den Bosch (Frans)
1997-01-01
textabstractIntroduction. Understanding why firms are successful is a very basic question in strategy both from a practitioner and a research perspective. In the strategy and management literature, however, we are confronted with different analytical frameworks, applicable at different levels of ana
Loghmani, Nick Mehrdad
2011-01-01
Harmonic theory provides a mathematical framework to describe the structure, behavior, evolution and emergence of harmonic systems. A harmonic system is context aware, contains elements that manifest characteristics either collaboratively or independently according to system's expression and can interact with its environment. This theory provides a fresh way to analyze emergence and collaboration of "ad-hoc" and complex systems.
Agrawal, Jugnu; Morin, Lisa L.
2016-01-01
Students with mathematics disabilities (MD) experience difficulties with both conceptual and procedural knowledge of different math concepts across grade levels. Research shows that concrete representational abstract framework of instruction helps to bridge this gap for students with MD. In this article, we provide an overview of this strategy…
Chen, Hsin-liang; Doty, Philip
2005-01-01
This article is the first of two that present a six-part conceptual framework for the design and evaluation of digital libraries meant to support mathematics education in K-12 settings (see also pt. 2). This first article concentrates on (1) information organization, (2) information literacy, and (3) integrated learning with multimedia materials.…
Retrofitting Non-Cognitive-Diagnostic Reading Assessment under the Generalized DINA Model Framework
Chen, Huilin; Chen, Jinsong
2016-01-01
Cognitive diagnosis models (CDMs) are psychometric models developed mainly to assess examinees' specific strengths and weaknesses in a set of skills or attributes within a domain. By adopting the Generalized-DINA model framework, the recently developed general modeling framework, we attempted to retrofit the PISA reading assessments, a…
How Are Questions That Students Ask in High Level Mathematics Classes Linked to General Giftedness?
Leikin, Roza; Koichu, Boris; Berman, Avi; Dinur, Sariga
2017-01-01
This paper presents a part of a larger study, in which we asked "How are learning and teaching of mathematics at high level linked to students' general giftedness?" We consider asking questions, especially student-generated questions, as indicators of quality of instructional interactions. In the part of the study presented in this…
Texas State Technical Coll. System, Waco.
This document contains descriptions of adult education courses in remediation, general education, and technical mathematics. They are part of a program developed by the Machine Tool Advanced Skills Technology Educational Resources (MASTER) program to help workers become competent in the skills needed to be productive workers in the machine tools…
On the injectivity of the generalized Radon transform arising in a model of mathematical economics
Agaltsov, A. D.
2016-11-01
In the present article we consider the uniqueness problem for the generalized Radon transform arising in a mathematical model of production. We prove uniqueness theorems for this transform and for the profit function in the corresponding model of production. Our approach is based on the multidimensional Wiener’s approximation theorems.
Fundamentals of sketch-based passwords a general framework
Riggan, Benjamin S; Wang, Cliff
2015-01-01
This SpringerBrief explores graphical password systems and examines novel drawing-based methods in terms of security, usability, and human computer-interactions. It provides a systematic approach for recognizing, comparing, and matching sketch-based passwords in the context of modern computing systems. The book offers both a security and usability analysis of the accumulative framework used for incorporating handwriting biometrics and a human computer-interaction performance analysis. The chapters offer new perspectives and experimental results regarding model uniqueness, recognition tolerance
A general framework for perfect simulation of long memory processes
De Santis, Emilio; Piccioni, Mauro
2010-01-01
In this paper a general approach for the perfect simulation of a stationary process with at most countable state space is outlined. The process is specified through a kernel, prescribing the probability of each state conditional to the whole past history. We follow the seminal paper of Comets, Fernandez and Ferrari, where sufficient conditions for the construction of a certain perfect simulation algorithm have been given. We generalize this approach by defining backward coalescence times for ...
Hassinger-Das, Brenna; Jordan, Nancy C.; Glutting, Joseph; Irwin, Casey; Dyson, Nancy
2013-01-01
Domain general skills that mediate the relation between kindergarten number sense and first-grade mathematics skills were investigated. Participants were 107 children who displayed low number sense in the fall of kindergarten. Controlling for background variables, multiple regression analyses showed that attention problems and executive functioning both were unique predictors of mathematics outcomes. Attention problems were more important for predicting first-grade calculation performance while executive functioning was more important for predicting first-grade performance on applied problems. Moreover, both executive functioning and attention problems were unique partial mediators of the relationship between kindergarten and first-grade mathematics skills. The results provide empirical support for developing interventions that target executive functioning and attention problems in addition to instruction in number skills for kindergartners with initial low number sense. PMID:24237789
A mathematical and numerical framework for magnetoacoustic tomography with magnetic induction
Ammari, Habib; Boulmier, Simon; Millien, Pierre
2015-11-01
We provide a mathematical analysis and a numerical framework for magnetoacoustic tomography with magnetic induction. The imaging problem is to reconstruct the conductivity distribution of biological tissue from measurements of the Lorentz force induced tissue vibration. We begin with reconstructing from the acoustic measurements the divergence of the Lorentz force, which is acting as the source term in the acoustic wave equation. Then we recover the electric current density from the divergence of the Lorentz force. To solve the nonlinear inverse conductivity problem, we introduce an optimal control method for reconstructing the conductivity from the electric current density. We prove its convergence and stability. We also present a point fixed approach and prove its convergence to the true solution. A new direct reconstruction scheme involving a partial differential equation is then proposed based on viscosity-type regularization to a transport equation satisfied by the electric current density field. We prove that solving such an equation yields the true conductivity distribution as the regularization parameter approaches zero. Finally, we test the three schemes numerically in the presence of measurement noise, quantify their stability and resolution, and compare their performance.
Balasis, Georgios; Potirakis, Stelios M.; Papadimitriou, Constantinos; Zitis, Pavlos I.; Eftaxias, Konstantinos
2015-04-01
The field of study of complex systems considers that the dynamics of complex systems are founded on universal principles that may be used to describe a great variety of scientific and technological approaches of different types of natural, artificial, and social systems. We apply concepts of the nonextensive statistical physics, on time-series data of observable manifestations of the underlying complex processes ending up to different extreme events, in order to support the suggestion that a dynamical analogy characterizes the generation of a single magnetic storm, solar flare, earthquake (in terms of pre-seismic electromagnetic signals) , epileptic seizure, and economic crisis. The analysis reveals that all the above mentioned different extreme events can be analyzed within similar mathematical framework. More precisely, we show that the populations of magnitudes of fluctuations included in all the above mentioned pulse-like-type time series follow the traditional Gutenberg-Richter law as well as a nonextensive model for earthquake dynamics, with similar nonextensive q-parameter values. Moreover, based on a multidisciplinary statistical analysis we show that the extreme events are characterized by crucial common symptoms, namely: (i) high organization, high compressibility, low complexity, high information content; (ii) strong persistency; and (iii) existence of clear preferred direction of emerged activities. These symptoms clearly discriminate the appearance of the extreme events under study from the corresponding background noise.
Eringen, A Cemal
2013-01-01
Continuum Physics: Volume 1 - Mathematics is a collection of papers that discusses certain selected mathematical methods used in the study of continuum physics. Papers in this collection deal with developments in mathematics in continuum physics and its applications such as, group theory functional analysis, theory of invariants, and stochastic processes. Part I explains tensor analysis, including the geometry of subspaces and the geometry of Finsler. Part II discusses group theory, which also covers lattices, morphisms, and crystallographic groups. Part III reviews the theory of invariants th
DEEP: a general computational framework for predicting enhancers
Kleftogiannis, Dimitrios A.
2014-11-05
Transcription regulation in multicellular eukaryotes is orchestrated by a number of DNA functional elements located at gene regulatory regions. Some regulatory regions (e.g. enhancers) are located far away from the gene they affect. Identification of distal regulatory elements is a challenge for the bioinformatics research. Although existing methodologies increased the number of computationally predicted enhancers, performance inconsistency of computational models across different cell-lines, class imbalance within the learning sets and ad hoc rules for selecting enhancer candidates for supervised learning, are some key questions that require further examination. In this study we developed DEEP, a novel ensemble prediction framework. DEEP integrates three components with diverse characteristics that streamline the analysis of enhancer\\'s properties in a great variety of cellular conditions. In our method we train many individual classification models that we combine to classify DNA regions as enhancers or non-enhancers. DEEP uses features derived from histone modification marks or attributes coming from sequence characteristics. Experimental results indicate that DEEP performs better than four state-of-the-art methods on the ENCODE data. We report the first computational enhancer prediction results on FANTOM5 data where DEEP achieves 90.2% accuracy and 90% geometric mean (GM) of specificity and sensitivity across 36 different tissues. We further present results derived using in vivo-derived enhancer data from VISTA database. DEEP-VISTA, when tested on an independent test set, achieved GM of 80.1% and accuracy of 89.64%. DEEP framework is publicly available at http://cbrc.kaust.edu.sa/deep/.
A general framework for perfect simulation of long memory processes
De Santis, Emilio
2010-01-01
In this paper a general approach for the perfect simulation of a stationary process with at most countable state space is outlined. The process is specified through a kernel, prescribing the probability of each state conditional to the whole past history. We follow the seminal paper of Comets, Fernandez and Ferrari, where sufficient conditions for the construction of a certain perfect simulation algorithm have been given. We generalize this approach by defining backward coalescence times for these kind of processes; this allows us to construct perfect simulation algorithms under weaker conditions.
Analysing the use of history of mathematics through MKT†
Jankvist, Uffe Thomas; Mosvold, Reidar; Fauskanger, Janne; Jakobsen, Arne
2015-05-01
In this article, we analyse three 'classical' cases of using history of mathematics in teacher training and reinterpret them using the framework of mathematical knowledge for teaching (MKT). We continue with a discussion of the potential benefits of applying MKT as a framework for discussion in research related to the use of history in mathematics education. MKT serves as an example of a framework from general mathematics education research which has something to offer in this respect. We argue that the MKT framework provides a powerful language to communicate results from research on the uses of history of mathematics to researchers in other areas of mathematics education research.
Some studies on mathematical models for general elastic multi-structures
Institute of Scientific and Technical Information of China (English)
HUANG Jianguo; SHI Zhongci; XU Yifeng
2005-01-01
The aim of this paper is to study the static problem about a general elastic multi-structure composed of an arbitrary number of elastic bodies, plates and rods. The mathematical model is derived by the variational principle and the principle of virtual work in a vector way. The unique solvability of the resulting problem is proved by the Lax-Milgram lemma after the presentation of a generalized Korn's inequality on general elastic multi-structures. The equilibrium equations are obtained rigorously by only assuming some reasonable regularity of the solution. An important identity is also given which is essential in the finite element analysis for the problem.
Request for All - Generalized Request Framework for PhEDEx
Huang, C-H; Ratnikova, N.; Sanchez-Hernandez, A.; Zhang, X.; Magini, N.
2014-01-01
PhEDEx has been serving CMS community since 2004 as the data broker. Every PhEDEx operation is initiated by a request, such as request to move data, request to delete data, and so on. A request has it own life cycle, including creation, approval, notification, and book keeping and the details depend on its type. Currently, only two kinds of requests, transfer and deletion, are fully integrated in PhEDEx. They are tailored specifically to the operations workflows. To be able to serve a new type of request it generally means a fair amount of development work.After several years of operation, we have gathered enough experience to rethink the request handling in PhEDEx. Generalized Request Project is set to abstract such experience and come up with a request system which is not tied into current workflow yet it is general enough to accommodate current and future requests.The challenges are dealing with different stages in a requests life cycle, complexity of approval process and complexity of the ability and auth...
A general framework for coloring problems: old results, new results, and open problems
Broersma, Haitze J.
2003-01-01
In this survey paper we present a general framework for coloring problems that was introduced in a joint paper which the author presented at WG2003. We show how a number of different types of coloring problems, most of which have been motivated from frequency assignment, fit into this framework. We
Regional development policies modelling: a framework of general equilibrium
Kancs, Artis
2001-01-01
The changes the rural economy and society experience today are wide ranging and complex. They stem to a large extent from changing socio-economic norms and values in a society as well as from the changes of the global economy, of the market policy and trade rules. These changes affect however, not only sectoral markets, but local economies and rural areas in general (FERMAN 1999). At the same time rural economies have to meet rising environmental and recreational claims of the society, which ...
National Research Council Canada - National Science Library
Nina Gumzej
2013-01-01
Proposed new EU general data protection legal framework profoundly affects a large number of day-to-day business operations of organizations processing personal data and calls for significant effort...
Directory of Open Access Journals (Sweden)
Goncharova Olga
2016-01-01
Full Text Available The two-dimensional films, flowing down an inclined, non-uniformly heated substrate are studied. The results contain the new mathematical models developed with the help of the long-wave approximation of the Navier-Stokes and heat transfer equations or Oberbeck-Boussinesq equations in the case, when the generalized conditions are formulated at thermocapillary interface. The evolution equations for the film thickness include the effects of gravity, viscosity, capillarity, thermocapillarity, additional stress effects and evaporation.
A mathematical model for phase separation: A generalized Cahn-Hilliard equation
Berti, Alessia; 10.1002/mma.1432
2011-01-01
In this paper we present a mathematical model to describe the phenomenon of phase separation, which is modelled as space regions where an order parameter changes smoothly. The model proposed, including thermal and mixing effects, is deduced for an incompressible fluid, so the resulting differential system couples a generalized Cahn-Hilliard equation with the Navier-Stokes equation. Its consistency with the second law of thermodynamics in the classical Clausius-Duhem form is finally proved.
Barriers to Curricular Change in General Education Mathematics at a Large Public Institution
Jorgensen, Marcus
2014-01-01
This qualitative study looked for barriers to curricular change in general education mathematics at a large public university (LPU) in the Western United States. The literature showed that a number of national organizations dealing in math education have recommended alternatives to the traditional algebra-intensive curriculum. LPU still relies predominantly on traditional College Algebra as its quantitative literacy (QL) course. With such an algebra-heavy emphasis, students may be missing mor...
A General Probabilistic Forecasting Framework for Offshore Wind Power Fluctuations
DEFF Research Database (Denmark)
Trombe, Pierre-Julien; Pinson, Pierre; Madsen, Henrik
2012-01-01
Accurate wind power forecasts highly contribute to the integration of wind power into power systems. The focus of the present study is on large-scale offshore wind farms and the complexity of generating accurate probabilistic forecasts of wind power fluctuations at time-scales of a few minutes...... power measurements only. We introduce an advanced Markov Chain Monte Carlo (MCMC) estimation method to account for the different features observed in an empirical time series of wind power: autocorrelation, heteroscedasticity and regime-switching. The model we propose is an extension of Markov......-Switching Autoregressive (MSAR) models with Generalized AutoRegressive Conditional Heteroscedastic (GARCH) errors in each regime to cope with the heteroscedasticity. Then, we analyze the predictive power of our model on a one-step ahead exercise of time series sampled over 10 min intervals. Its performances are compared...
A General Probabilistic Forecasting Framework for Offshore Wind Power Fluctuations
Directory of Open Access Journals (Sweden)
Henrik Madsen
2012-03-01
Full Text Available Accurate wind power forecasts highly contribute to the integration of wind power into power systems. The focus of the present study is on large-scale offshore wind farms and the complexity of generating accurate probabilistic forecasts of wind power fluctuations at time-scales of a few minutes. Such complexity is addressed from three perspectives: (i the modeling of a nonlinear and non-stationary stochastic process; (ii the practical implementation of the model we proposed; (iii the gap between working on synthetic data and real world observations. At time-scales of a few minutes, offshore fluctuations are characterized by highly volatile dynamics which are difficult to capture and predict. Due to the lack of adequate on-site meteorological observations to relate these dynamics to meteorological phenomena, we propose a general model formulation based on a statistical approach and historical wind power measurements only. We introduce an advanced Markov Chain Monte Carlo (MCMC estimation method to account for the different features observed in an empirical time series of wind power: autocorrelation, heteroscedasticity and regime-switching. The model we propose is an extension of Markov-Switching Autoregressive (MSAR models with Generalized AutoRegressive Conditional Heteroscedastic (GARCH errors in each regime to cope with the heteroscedasticity. Then, we analyze the predictive power of our model on a one-step ahead exercise of time series sampled over 10 min intervals. Its performances are compared to state-of-the-art models and highlight the interest of including a GARCH specification for density forecasts.
Mathematical Physics Framework SustainingNatural Anticipation and Selection of Attention
Directory of Open Access Journals (Sweden)
Alfons Salden
2005-04-01
Full Text Available An ambient intelligent environment is definitely a prerequisite for anticipating the needs and catching the attention of systems. But how to endow such an environment with natural anticipatory and attentive features is still a hardly ever properly addressed question. Before providing a roadmap towards such an ambient intelligent environment we first give cognitive-ergonomic accounts for how natural anticipation and selection of attention (NASA emerge in living organisms. In particular, we describe why, when and how exploratory and goal-directed acts by living organisms are controlled while optimizing their changing and limited structural and functional capabilities of multimodal sensor, cognitive and actuator systems. Next, we describe how NASA can be embedded and embodied in sustainable intelligent multimodal systems (SIMS. Such systems allow an ambient intelligent environment to (self- interact taking its contexts into account. In addition, collective intelligent agents (CIA distribute, store, extend, maintain, optimize, diversify and sustain the NASA embedded and embodied in the ambient intelligent environment. Finally, we present the basic ingredients of a mathematical-physical framework for empirically modeling and sustaining NASA within SIMS by CIA in an ambient intelligent environment. An environment which is modeled this way, robustly and reliably over time aligns multi-sensor detection and fusion; multimodal fusion, dialogue planning and fission; multi actuator fission, rendering and presentation schemes. NASA residing in such an environment are then active within every phase of perception-decision-action cycles, and are gauged and renormalized to its physics. After determining and assessing across several evolutionary dynamic scales appropriate fitness, utility and measures, NASA can be realized by reinforcement learning and self-organization.
Stein, Sherman K
2010-01-01
Anyone can appreciate the beauty, depth, and vitality of mathematics with the help of this highly readable text, specially developed from a college course designed to appeal to students in a variety of fields. Readers with little mathematical background are exposed to a broad range of subjects chosen from number theory, topology, set theory, geometry, algebra, and analysis. Starting with a survey of questions on weight, the text discusses the primes, the fundamental theorem of arithmetic, rationals and irrationals, tiling, tiling and electricity, probability, infinite sets, and many other topi
Directory of Open Access Journals (Sweden)
Mahomed S Patel
Full Text Available BACKGROUND: Although primary health care, and in particular, general practice will be at the frontline in the response to pandemic influenza, there are no frameworks to guide systematic planning for this task or to appraise available plans for their relevance to general practice. We aimed to develop a framework that will facilitate planning for general practice, and used it to appraise pandemic plans from Australia, England, USA, New Zealand and Canada. METHODOLOGY/PRINCIPAL FINDINGS: We adapted the Haddon matrix to develop the framework, populating its cells through a multi-method study that incorporated the peer-reviewed and grey literature, interviews with general practitioners, practice nurses and senior decision-makers, and desktop simulation exercises. We used the framework to analyse 89 publicly-available jurisdictional plans at similar managerial levels in the five countries. The framework identifies four functional domains: clinical care for influenza and other needs, public health responsibilities, the internal environment and the macro-environment of general practice. No plan addressed all four domains. Most plans either ignored or were sketchy about non-influenza clinical needs, and about the contribution of general practice to public health beyond surveillance. Collaborations between general practices were addressed in few plans, and inter-relationships with the broader health system, even less frequently. CONCLUSIONS: This is the first study to provide a framework to guide general practice planning for pandemic influenza. The framework helped identify critical shortcomings in available plans. Engaging general practice effectively in planning is challenging, particularly where governance structures for primary health care are weak. We identify implications for practice and for research.
A general maximum entropy framework for thermodynamic variational principles
Energy Technology Data Exchange (ETDEWEB)
Dewar, Roderick C., E-mail: roderick.dewar@anu.edu.au [Research School of Biology, The Australian National University, Canberra ACT 0200 (Australia)
2014-12-05
Minimum free energy principles are familiar in equilibrium thermodynamics, as expressions of the second law. They also appear in statistical mechanics as variational approximation schemes, such as the mean-field and steepest-descent approximations. These well-known minimum free energy principles are here unified and extended to any system analyzable by MaxEnt, including non-equilibrium systems. The MaxEnt Lagrangian associated with a generic MaxEnt distribution p defines a generalized potential Ψ for an arbitrary probability distribution p-hat, such that Ψ is a minimum at (p-hat) = p. Minimization of Ψ with respect to p-hat thus constitutes a generic variational principle, and is equivalent to minimizing the Kullback-Leibler divergence between p-hat and p. Illustrative examples of min–Ψ are given for equilibrium and non-equilibrium systems. An interpretation of changes in Ψ is given in terms of the second law, although min–Ψ itself is an intrinsic variational property of MaxEnt that is distinct from the second law.
A general maximum entropy framework for thermodynamic variational principles
Dewar, Roderick C.
2014-12-01
Minimum free energy principles are familiar in equilibrium thermodynamics, as expressions of the second law. They also appear in statistical mechanics as variational approximation schemes, such as the mean-field and steepest-descent approximations. These well-known minimum free energy principles are here unified and extended to any system analyzable by MaxEnt, including non-equilibrium systems. The MaxEnt Lagrangian associated with a generic MaxEnt distribution p defines a generalized potential Ψ for an arbitrary probability distribution ̂p, such that Ψ is a minimum at ̂p = p. Minimization of Ψ with respect to ̂p thus constitutes a generic variational principle, and is equivalent to minimizing the Kullback-Leibler divergence between ̂p and p. Illustrative examples of min-Ψ are given for equilibrium and non-equilibrium systems. An interpretation of changes in Ψ is given in terms of the second law, although min-Ψ itself is an intrinsic variational property of MaxEnt that is distinct from the second law.
A Framework of Principles for Quantum General Relativity with Time and Measurement
Maran, Suresh K
2013-01-01
The purpose of this article is to outline a framework of concepts and principles to combine quantum mechanics and general relativity so that time and measurement (reduction) are present as integral parts of the basic foundations. First, the problem of time in quantum gravity and the measurement problem in quantum mechanics are briefly reviewed and the popular proposals to tackle these two problems are briefly discussed. Next, on the already known foundations of quantum mechanics, a framework of principles of dynamics is built: 1) Self-Time Evolution - Newtons first law is reinterpreted to define time, 2) Local Measurement by Local Reduction - Quantum diffusion theory is adapted, and 3) Global Evolution by Global Reduction. Ideas on how to apply the framework to study quantum general relativistic physics are discussed. Further, more general and modified forms of some of these principles are also discussed. The theoretical elements in the framework to be made concrete by further theoretical and experimental inv...
Lanzalaco, Felix; Pissanetzky, Sergio
2013-12-01
A recent theory of physical information based on the fundamental principles of causality and thermodynamics has proposed that a large number of observable life and intelligence signals can be described in terms of the Causal Mathematical Logic (CML), which is proposed to encode the natural principles of intelligence across any physical domain and substrate. We attempt to expound the current definition of CML, the "Action functional" as a theory in terms of its ability to possess a superior explanatory power for the current neuroscientific data we use to measure the mammalian brains "intelligence" processes at its most general biophysical level. Brain simulation projects define their success partly in terms of the emergence of "non-explicitly programmed" complex biophysical signals such as self-oscillation and spreading cortical waves. Here we propose to extend the causal theory to predict and guide the understanding of these more complex emergent "intelligence Signals". To achieve this we review whether causal logic is consistent with, can explain and predict the function of complete perceptual processes associated with intelligence. Primarily those are defined as the range of Event Related Potentials (ERP) which include their primary subcomponents; Event Related Desynchronization (ERD) and Event Related Synchronization (ERS). This approach is aiming for a universal and predictive logic for neurosimulation and AGi. The result of this investigation has produced a general "Information Engine" model from translation of the ERD and ERS. The CML algorithm run in terms of action cost predicts ERP signal contents and is consistent with the fundamental laws of thermodynamics. A working substrate independent natural information logic would be a major asset. An information theory consistent with fundamental physics can be an AGi. It can also operate within genetic information space and provides a roadmap to understand the live biophysical operation of the phenotype
van den Heuvel-Panhuizen, Marja; Elia, Iliada
2012-01-01
The purpose of this study was to investigate what experts in the use of picturebooks in mathematics education consider powerful characteristics of such books in the support of young children's learning of mathematics. The study started by investigating experts' views of such characteristics, as reflected in academic and professional publications…
Lowrie, Tom; Diezmann, Carmel M.; Logan, Tracy
2012-01-01
Graphical tasks have become a prominent aspect of mathematics assessment. From a conceptual stance, the purpose of this study was to better understand the composition of graphical tasks commonly used to assess students' mathematics understandings. Through an iterative design, the investigation described the sense making of 11-12-year-olds as they…
Techno-Mathematical Discourse: A Conceptual Framework for Analyzing Classroom Discussions
Anderson-Pence, Katie L.
2017-01-01
Extensive research has been published on the nature of classroom mathematical discourse and on the impact of technology tools, such as virtual manipulatives (VM), on students' learning, while less research has focused on how technology tools facilitate that mathematical discourse. This paper presents an emerging construct, the Techno-Mathematical…
Towards the Construction of a Framework to Deal with Routine Problems to Foster Mathematical Inquiry
Santos-Trigo, Manuel; Camacho-Machin, Matias
2009-01-01
To what extent does the process of solving textbook problems help students develop a way of thinking that is consistent with mathematical practice? Can routine problems be transformed into problem solving activities that promote students' mathematical reflection? These questions are used to outline and discuss features of an inquiry framework…
Towards the Construction of a Framework to Deal with Routine Problems to Foster Mathematical Inquiry
Santos-Trigo, Manuel; Camacho-Machin, Matias
2009-01-01
To what extent does the process of solving textbook problems help students develop a way of thinking that is consistent with mathematical practice? Can routine problems be transformed into problem solving activities that promote students' mathematical reflection? These questions are used to outline and discuss features of an inquiry framework…
van den Heuvel-Panhuizen, Marja; Elia, Iliada
2012-01-01
The purpose of this study was to investigate what experts in the use of picturebooks in mathematics education consider powerful characteristics of such books in the support of young children's learning of mathematics. The study started by investigating experts' views of such characteristics, as reflected in academic and professional publications…
Cowan, Richard; Powell, Daisy
2014-01-01
Explanations of the marked individual differences in elementary school mathematical achievement and mathematical learning disability (MLD or dyscalculia) have involved domain-general factors (working memory, reasoning, processing speed, and oral language) and numerical factors that include single-digit processing efficiency and multidigit skills…
Hines, Claudia L.; Brown, Nina W.; Myran, Steve
2016-01-01
Ninety-three (n = 93) students in grades 9-12 who failed the Virginia Standards of Learning mathematics test were placed into experimental and control groups. Pre and posttest measures for general and mathematics anxiety, and physical symptoms of stress were administered. The Expressive Writing intervention was used with both groups where the…
Anion stripping as a general method to create cationic porous framework with mobile anions.
Mao, Chengyu; Kudla, Ryan A; Zuo, Fan; Zhao, Xiang; Mueller, Leonard J; Bu, Xianhui; Feng, Pingyun
2014-05-28
Metal-organic frameworks (MOFs) with cationic frameworks and mobile anions have many applications from sensing, anion exchange and separation, to fast ion conductivity. Despite recent progress, the vast majority of MOFs have neutral frameworks. A common mechanism for the formation of neutral frameworks is the attachment of anionic species such as F(-) or OH(-) to the framework metal sites, neutralizing an otherwise cationic scaffolding. Here, we report a general method capable of converting such neutral frameworks directly into cationic ones with concurrent generation of mobile anions. Our method is based on the differential affinity between distinct metal ions with framework anionic species. Specifically, Al(3+) is used to strip F(-) anions away from framework Cr(3+) sites, leading to cationic frameworks with mobile Cl(-) anions. The subsequent anion exchange with OH(-) further leads to a porous network with mobile OH(-) anions. New materials prepared by anion stripping can undergo ion exchange with anionic organic dyes and also exhibit much improved ionic conductivity compared to the original unmodified MOFs.
Hawks, Kristel W.
2010-01-01
The purpose of this study was to determine if teachers who developed lessons based on Bloom's Taxonomy and the "Virginia Standards of Learning Curriculum Framework" saw increased scores on the mathematics benchmark assessment for fourth grade. Two classes taught by different mathematics teachers participated. The mean of the posttest scores for…
Hawks, Kristel W.
2010-01-01
The purpose of this study was to determine if teachers who developed lessons based on Bloom's Taxonomy and the "Virginia Standards of Learning Curriculum Framework" saw increased scores on the mathematics benchmark assessment for fourth grade. Two classes taught by different mathematics teachers participated. The mean of the posttest…
Where learning starts? A framework for thinking about lectures in university mathematics
Pritchard, David
2010-07-01
Lectures have been widely criticized as a method of teaching, but remain a standard component of most university mathematics courses. Does this necessarily harm students' education? This critical review contends that many arguments against lecturing are misconceived, at least when applied to mathematics. The effectiveness of lectures in carrying out various functions is discussed with reference to some recent educational research. There is evidence that lectures can be effective in communicating information, modelling reasoning and motivating students. Therefore, when supported appropriately by other activities, lectures provide an effective component of a mathematical education.
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
The constraints and the operations play an important role in database generaliza tion.They guide and govern database generalization.The constraints are translation of the required conditions that should take into account not only the objects and relationships among objects but also spatial d a ta schema (classification and aggregation hierarchy) associated with the final e xi sting database.The operations perform the actions of generalization in support o f data reduction in the database. The constraints in database generalization are still lack of research.There is still the lack of frameworks to express the con straints and the operations on the basis of object_oriented data structure in da tabase generalization.This paper focuses on the frameworks for generalization op erations and constraints on the basis of object_oriented data structure in datab ase gen eralization.The constraints as the attributes of the object and the operations a s the methods of the object can be encapsulated in classes. They have the in heritance and polymorphism property. So the framework of the constraints and the operations which are based on object_oriented data structure can be eas ily understood and implemented. The constraint and the operations based on obje ct_oriented database are proposed based on object_oriented database.The framewor ks for generalization operations,constraints and relations among objects based o n object_oriented data structure in database generalization are designed.The cat egorical database generalization is concentrated on in this paper.
A General SDN-Based IoT Framework with NVF Implementation
Institute of Scientific and Technical Information of China (English)
Jie Li; Eitan Altman; Corinne Touati
2015-01-01
The emerging technologies of Internet of Things (IoT), soft⁃ware defined networking (SDN), and network function virtual⁃ization (NFV) have great potential for the information service innovation in the cloud and big data era. The architecture models of IoT, SDN with NFV implementation are studied in this paper. A general SDN⁃based IoT framework with NFV implantation is presented. This framework takes advantages of SDN and NFV and improves IoT architecture.
Träff, Ulf
2013-10-01
This study examined the relative contributions of general cognitive abilities and number abilities to word problem solving, calculation, and arithmetic fact retrieval in a sample of 134 children aged 10 to 13 years. The following tasks were administered: listening span, visual matrix span, verbal fluency, color naming, Raven's Progressive Matrices, enumeration, number line estimation, and digit comparison. Hierarchical multiple regressions demonstrated that number abilities provided an independent contribution to fact retrieval and word problem solving. General cognitive abilities contributed to problem solving and calculation. All three number tasks accounted for a similar amount of variance in fact retrieval, whereas only the number line estimation task contributed unique variance in word problem solving. Verbal fluency and Raven's matrices accounted for an equal amount of variance in problem solving and calculation. The current findings demonstrate, in accordance with Fuchs and colleagues' developmental model of mathematical learning (Developmental Psychology, 2010, Vol. 46, pp. 1731-1746), that both number abilities and general cognitive abilities underlie 10- to 13-year-olds' proficiency in problem solving, whereas only number abilities underlie arithmetic fact retrieval. Thus, the amount and type of cognitive contribution to arithmetic proficiency varies between the different aspects of arithmetic. Furthermore, how closely linked a specific aspect of arithmetic is to the whole number representation systems is not the only factor determining the amount and type of cognitive contribution in 10- to 13-year-olds. In addition, the mathematical complexity of the task appears to influence the amount and type of cognitive support.
Group Classification of a General Bond-Option Pricing Equation of Mathematical Finance
Directory of Open Access Journals (Sweden)
Tanki Motsepa
2014-01-01
Full Text Available We carry out group classification of a general bond-option pricing equation. We show that the equation admits a three-dimensional equivalence Lie algebra. We also show that some of the values of the constants which result from group classification give us well-known models in mathematics of finance such as Black-Scholes, Vasicek, and Cox-Ingersoll-Ross. For all such values of these arbitrary constants we obtain Lie point symmetries. Symmetry reductions are then obtained and group invariant solutions are constructed for some cases.
A general model for Io's neutral gas clouds. I - Mathematical description
Smyth, W. H.; Combi, M. R.
1988-01-01
A general mathematical formalism for calculating the physical properties of any of Io's neutral gas clouds (Na, K, O, S, SO2) is presented. The dynamical effects of both the gravitational fields of Io and Jupiter and solar radiation pressure are included, in addition to the many complex space- and time-dependent interactions that occur between the neutral clouds and the plasma torus. The importance of this new model in studying both the plasma conditions prevalent in the inner planetary magnetosphere and the nature of Io's local atmosphere is discussed. A numerical method for evaluating the physical properties of the neutral clouds using the new model is described.
A Generalized Recursive Algorithm for Binary Multiplication based on Vedic Mathematics
Kale, Ajinkya; Joglekar, Ashish
2009-01-01
A generalized algorithm for multiplication is proposed through recursive application of the Nikhilam Sutra from Vedic Mathematics, operating in radix - 2 number system environment suitable for digital platforms. Statistical analysis has been carried out based on the number of recursions profile as a function of the smaller multiplicand. The proposed algorithm is efficient for smaller multiplicands as well, unlike most of the asymptotically fast algorithms. Further, a basic block schematic of Hardware Implementation of our algorithm is suggested to exploit parallelism and speed up the implementation of the algorithm in a multiprocessor environment.
Herrera, L; Ibañez, J; Ospino, J
2014-01-01
We carry out a general study on the collapse of axially (and reflection) symmetric sources in the context of general relativity. All basic equations and concepts required to perform such a general study are deployed. These equations are written down for a general anisotropic dissipative fluid. The proposed approach allows for analytical studies as well as for numerical applications. A causal transport equation derived from the Israel-Stewart theory is applied, to discuss some thermodynamic aspects of the problem. A set of scalar functions (the structure scalars) derived from the orthogonal splitting of the Riemann tensor are calculated and their role in the dynamics of the source is clearly exhibited. The characterization of the gravitational radiation emitted by the source is discussed.
Eftimie, Raluca
2015-03-01
One of the main unsolved problems of modern physics is finding a "theory of everything" - a theory that can explain, with the help of mathematics, all physical aspects of the universe. While the laws of physics could explain some aspects of the biology of living systems (e.g., the phenomenological interpretation of movement of cells and animals), there are other aspects specific to biology that cannot be captured by physics models. For example, it is generally accepted that the evolution of a cell-based system is influenced by the activation state of cells (e.g., only activated and functional immune cells can fight diseases); on the other hand, the evolution of an animal-based system can be influenced by the psychological state (e.g., distress) of animals. Therefore, the last 10-20 years have seen also a quest for a "theory of everything"-approach extended to biology, with researchers trying to propose mathematical modelling frameworks that can explain various biological phenomena ranging from ecology to developmental biology and medicine [1,2,6]. The basic idea behind this approach can be found in a few reviews on ecology and cell biology [6,7,9-11], where researchers suggested that due to the parallel between the micro-scale dynamics and the emerging macro-scale phenomena in both cell biology and in ecology, many mathematical methods used for ecological processes could be adapted to cancer modelling [7,9] or to modelling in immunology [11]. However, this approach generally involved the use of different models to describe different biological aspects (e.g., models for cell and animal movement, models for competition between cells or animals, etc.).
Monaghan, John
2013-01-01
This paper offers a framework, an extension of Valsiner's "zone theory", for the analysis of joint student-teacher development over a series of technology-based mathematics lessons. The framework is suitable for developing research studies over a moderately long period of time and considers interrelated student-teacher development as…
Rotem, Avital; Henik, Avishai
2015-01-01
We examined the development of sensitivity to general and specific numerical features in typical achievers and in 6th and 8th graders with mathematics learning disability (MLD), using two effects in mental multiplication: operand-relatedness (i.e., difficulty in avoiding errors that are related to the operands via a shared multiplication row) and decade-consistency (i.e., difficulty in avoiding errors that are operand related and also share a decade with the true result). Responses to decade-consistent products were quick but erroneous. In line with the processing sequence in adults, children first became sensitive to the general numerical feature of operand-relatedness (typical achievers--from 3rd grade; children with MLD in 8th grade) and only later to the specific feature of decade-consistency (typical achievers--from 4th grade, but only from 6th grade in a mature pattern). Implications of the numerical sensitivity in children with MLD are discussed.
Buchheister, Kelley; Jackson, Christa; Taylor, Cynthia E.
2014-01-01
Traditionally, teacher education programs have placed little emphasis on preparing mathematics teachers to work with students who struggle in mathematics. Therefore, it is crucial that mathematics teacher educators explicitly prepare prospective teachers to instruct students who struggle with mathematics by providing strategies and practices that…
Taquet, Maxime; Scherrer, Benoit; Commowick, Olivier; Peters, Jurriaan M; Sahin, Mustafa; Macq, Benoit; Warfield, Simon K
2014-02-01
Diffusion tensor imaging (DTI) is unable to represent the diffusion signal arising from multiple crossing fascicles and freely diffusing water molecules. Generative models of the diffusion signal, such as multi-fascicle models, overcome this limitation by providing a parametric representation for the signal contribution of each population of water molecules. These models are of great interest in population studies to characterize and compare the brain microstructural properties. Central to population studies is the construction of an atlas and the registration of all subjects to it. However, the appropriate definition of registration and atlasing methods for multi-fascicle models have proven challenging. This paper proposes a mathematical framework to register and analyze multi-fascicle models. Specifically, we define novel operators to achieve interpolation, smoothing and averaging of multi-fascicle models. We also define a novel similarity metric to spatially align multi-fascicle models. Our framework enables simultaneous comparisons of different microstructural properties that are confounded in conventional DTI. The framework is validated on multi-fascicle models from 24 healthy subjects and 38 patients with tuberous sclerosis complex, 10 of whom have autism. We demonstrate the use of the multi-fascicle models registration and analysis framework in a population study of autism spectrum disorder.
A general theoretical framework for decoherence in open and closed systems
Castagnino, Mario; Fortin, Sebastian; Laura, Roberto; Lombardi, Olimpia
2008-08-01
A general theoretical framework for decoherence is proposed, which encompasses formalisms originally devised to deal just with open or closed systems. The conditions for decoherence are clearly stated and the relaxation and decoherence times are compared. Finally, the spin-bath model is developed in detail from the new perspective.
A general theoretical framework for decoherence in open and closed systems
Energy Technology Data Exchange (ETDEWEB)
Castagnino, Mario [CONICET, IAFE, Instituto de Fisica de Rosario, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Casilla de Correos 67, Sucursal 28, 1428, Buenos Aires (Argentina); Fortin, Sebastian [CONICET, IAFE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Casilla de Correos 67, Sucursal 28, 1428, Buenos Aires (Argentina); Laura, Roberto [Departamento de Fisica y Quimica, Facultad de Ciencias Exactas, IngenierIa y Agrimensura, Universidad Nacional de Rosario, Pellegrini 250, 2000, Rosario (Argentina); Lombardi, Olimpia [CONICET, Universidad de Buenos Aires, Crisologo Larralde 3440, 1430, Buenos Aires (Argentina)
2008-08-07
A general theoretical framework for decoherence is proposed, which encompasses formalisms originally devised to deal just with open or closed systems. The conditions for decoherence are clearly stated and the relaxation and decoherence times are compared. Finally, the spin-bath model is developed in detail from the new perspective.
Toward a Model Framework of Generalized Parallel Componential Processing of Multi-Symbol Numbers
Huber, Stefan; Cornelsen, Sonja; Moeller, Korbinian; Nuerk, Hans-Christoph
2015-01-01
In this article, we propose and evaluate a new model framework of parallel componential multi-symbol number processing, generalizing the idea of parallel componential processing of multi-digit numbers to the case of negative numbers by considering the polarity signs similar to single digits. In a first step, we evaluated this account by defining…
A general framework for implementing NLO calculations in shower Monte Carlo programs. The POWHEG BOX
Energy Technology Data Exchange (ETDEWEB)
Alioli, Simone [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Nason, Paolo [INFN, Milano-Bicocca (Italy); Oleari, Carlo [INFN, Milano-Bicocca (Italy); Milano-Bicocca Univ. (Italy); Re, Emanuele [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology
2010-02-15
In this work we illustrate the POWHEG BOX, a general computer code framework for implementing NLO calculations in shower Monte Carlo programs according to the POWHEG method. Aim of this work is to provide an illustration of the needed theoretical ingredients, a view of how the code is organized and a description of what a user should provide in order to use it. (orig.)
Ufer, Stefan; Rach, Stefanie; Kosiol, Timo
2017-01-01
Students' motivational characteristics, e.g., subject-related interest, are considered important predictors for successful learning processes. However, few empirical studies provide evidence for the assumed chain of effects between high interest and high achievement in mathematics. One reason for this result might be that the applied measures of…
The contribution of general cognitive abilities and approximate number system to early mathematics.
Passolunghi, Maria Chiara; Cargnelutti, Elisa; Pastore, Massimiliano
2014-12-01
Math learning is a complex process that entails a wide range of cognitive abilities to be fulfilled. There is sufficient evidence that both general and specific cognitive skills assume a fundamental role, despite the absence of shared consensus about the relative extent of their involvement. Moreover, regarding general abilities, there is no agreement about the recruitment of the different memory components or of intelligence. In relation to specific factors, great debate subsists regarding the role of the approximate number system (ANS). Starting from these considerations, we wanted to conduct a wide assessment of memory components and ANS, by controlling for the effects associated with intelligence and also exploring possible relationships between all precursors. To achieve this purpose, a sample of 157 children was tested at both beginning and end of their Grade 1. Both general (memory and intelligence) and specific (ANS) precursors were evaluated by a wide battery of tests and put in relation to concurrent and subsequent math skills. Memory was explored in passive and active aspects involving both verbal and visuo-spatial components. Path analysis results demonstrated that memory, and especially the more active processes, and intelligence were the strongest precursors in both assessment times. ANS had a milder role which lost significance by the end of the school year. Memory and ANS seemed to influence early mathematics almost independently. Both general and specific precursors seemed to have a crucial role in early math competences, despite the lower involvement of ANS. © 2014 The British Psychological Society.
Directory of Open Access Journals (Sweden)
Fethi Bin Muhammad Belgacem
2014-10-01
Full Text Available In this paper, using the Extended Trial Equation (ETEM, we get new traveling wave solutions of the Generalized Benjamin, the Generalized Burger-Kdv Equations (GBE, GBKE. The obtained solutions not only constitute a novel analytical viewpoint in nonlinear complex phenomena, but they also form a new stand alone basis from which physical applications in this arena can be comprehended further, and moreover investigated. Furthermore, to concretely enrich this research production, we provide illustrative, Mathematica Release 7 based, 3D graphics of the gotten solutions, with well chosen, yet structure revealing parameters.
A generalized mathematical model to determine the turning movement counts at
Directory of Open Access Journals (Sweden)
Al-Sayed Ahmed Al-Sobky
2014-09-01
Full Text Available Traffic turning movement counts at roundabouts is one of the key inputs required for roundabout assessment, control and management. Traditionally, a direct counting is conducted to track a vehicle from entering through circulation until exiting. This counting may be difficult and costly due to the size of roundabout, the vision obstacles, and the continuous traffic flow. Many researchers tried to avoid the tracking problem by counting only at entries and exits, then estimating the movements based on historical data which unfortunately affect the results. Other researchers reduced the tracking problem by counting some turning movements in addition to at entries and exits, then calculating mathematically the remaining movements. This approach is practical and accurate; however, it was applied on limited cases. In this paper, a generalized mathematical model was developed to calculate the most difficult movements based on the easiest movements determined based on the size of monitoring area. The developed model can be used to calculate the turning movements, including the u-turns, for roundabouts with any number of legs. The developed model was presented in O–D matrix forms to be practical and user-friendly. The model was validated against reference count data and the results were found to be satisfactory.
König, Johannes; Blömeke, Sigrid; Kaiser, Gabriele
2015-01-01
We examined several facets of general pedagogical knowledge and skills of early career mathematics teachers, asking how they are associated with characteristics of teacher education, teaching experience, and working conditions. Declarative general pedagogical knowledge (GPK) was assessed via a paper-and-pencil test, while early career teachers'…
Development of a Framework to Characterise the Openness of Mathematical Tasks
Yeo, Joseph B. W.
2017-01-01
Educators usually mean different constructs when they speak of open tasks: some may refer to pure-mathematics investigative tasks while others may have authentic real-life tasks in mind; some may think of the answer being open while others may refer to an open method. On the other hand, some educators use different terms, e.g. open and open-ended,…
Kuehn, Christian
2011-06-01
Bifurcations can cause dynamical systems with slowly varying parameters to transition to far-away attractors. The terms “critical transition” or “tipping point” have been used to describe this situation. Critical transitions have been observed in an astonishingly diverse set of applications from ecosystems and climate change to medicine and finance. The main goal of this paper is to give an overview which standard mathematical theories can be applied to critical transitions. We shall focus on early-warning signs that have been suggested to predict critical transitions and point out what mathematical theory can provide in this context. Starting from classical bifurcation theory and incorporating multiple time scale dynamics one can give a detailed analysis of local bifurcations that induce critical transitions. We suggest that the mathematical theory of fast-slow systems provides a natural definition of critical transitions. Since noise often plays a crucial role near critical transitions the next step is to consider stochastic fast-slow systems. The interplay between sample path techniques, partial differential equations and random dynamical systems is highlighted. Each viewpoint provides potential early-warning signs for critical transitions. Since increasing variance has been suggested as an early-warning sign we examine it in the context of normal forms analytically, numerically and geometrically; we also consider autocorrelation numerically. Hence we demonstrate the applicability of early-warning signs for generic models. We end with suggestions for future directions of the theory.
Brown, J B; Morrison, Tracy; Bryant, Melanie; Kassell, Lisa; Nestel, Debra
2015-01-01
There is increasing pressure for Australian rural general practices to engage in educational delivery as a means of addressing workforce issues and accommodating substantial increases in learners. For practices that have now developed a strong focus on education, there is the challenge to complement this by engaging in research activity. This study develops a rural academic general practice framework to assist rural practices in developing both comprehensive educational activity and a strong research focus thus moving towards functioning as mature academic units. A case study research design was used with the unit of analysis at the level of the rural general practice. Purposively sampled practices were recruited and individual interviews conducted with staff (supervisors, practice managers, nurses), learners (medical students, interns and registrars) and patients. Three practices hosted 'multi-level learners', two practices hosted one learner group and one had no learners. Forty-four individual interviews were conducted with staff, learners and patients. Audio recordings were transcribed for thematic analysis. After initial inductive coding, deductive analysis was undertaken with reference to recent literature and the expertise of the research team resulting in the rural academic general practice framework. Three key themes emerged with embedded subthemes. For the first theme, organisational considerations, subthemes were values/vision/culture, patient population and clinical services, staffing, physical infrastructure/equipment, funding streams and governance. For the second theme, educational considerations, subthemes were processes, clinical supervision, educational networks and learner presence. Third, for research considerations, there were the subthemes of attitude to research and research activity. The framework maps the development of a rural academic practice across these themes in four progressive stages: beginning, emerging, consolidating and
Directory of Open Access Journals (Sweden)
Samuel L. Tunstall
2016-07-01
Full Text Available In this paper, we describe the process at Michigan State University whereby we have created two courses, Math 101 and 102, designed to foster numeracy and alleviate mathematics anxiety. The courses--which are not sequential--provide a means of satisfying the University's general education requirement without taking college algebra or calculus, among other options. They are context-driven and broken into modules such as "The World and Its People" and "Health and Risk." They have been highly successful thus far, with students providing positive feedback on their interest in the material and the utility they see of it in their daily lives. We include background on the courses' history, their current status, and present and future challenges, ending with suggestions for others as they attempt to implement quantitative literacy courses at their own institution.
Institute of Scientific and Technical Information of China (English)
方勤华
2012-01-01
数学专业素养指教师实施高质量数学教学需要的数学知识、数学能力和数学情意的综合统一体.教师的数学知识包括：数学内容及其蕴含的数学思想方法知识,数学观念知识和数学结构知识.教师数学能力包括基本数学能力,提出、分析和解决数学问题的能力,处理并使用数学语言的能力.教师的数学情意是＂数学学习倾向＂与＂数学专业自我＂的综合体.%An initial framework for describing teachers＇ mathematics professional literacy needed by a high quality mathematics teaching is built according to literature review and the interview of 8 expert mathematics teachers. Then, taking the initial framework as a questionnaire collects teachers＇ views on the perceived level of importance and the perceived level of mastery for each teacher literacy by 637 practicing teachers in Henan province. According to the survey data, the initial framework is refined. Finally, the framework is determined for describing high school mathematics teachers＇ mathematics professional literacy.
Switched Systems Reduction Framework Based on Convex Combination of Generalized Gramians
Directory of Open Access Journals (Sweden)
Hamid Reza Shaker
2009-01-01
Full Text Available A general method for model-order reduction of switched linear dynamical systems is presented. The proposed technique uses convex generalized gramian which is a convex combination of the generalized gramians. It is shown that different classical reduction methods can be developed into the generalized gramian framework for model reduction of linear systems and further for the reduction of switched systems by construction of the convex generalized gramian. Balanced reduction within specified frequency bound is taken as an example which is developed within this framework. In order to avoid numerical instability and also to increase the numerical efficiency, convex generalized gramian-based Petrov-Galerkin projection is constructed instead of the similarity transform approach for reduction. It is proven that the method preserves the stability of the original switched system at least for stabilizing switching signal and it is also less conservative than the method which is based on the common generalized gramian. Some discussions on the coefficient of the vertices of the convex variables are presented. The performance of the proposed method is illustrated by numerical examples.
Energy Technology Data Exchange (ETDEWEB)
Basurto C, J. [Comision Nacional de Seguridad Nuclear y Salvaguardias, Dr. Jose Ma. Barragan No. 779, Col. Narvarte, 03020 Mexico D. F. (Mexico)
2008-12-15
Of the six existing hierarchy in the Mexican legal system, the first five of the Constitution of the Mexican Official Norms have a binding character, containing mandatory requirements to meet, while the sixth is not binding. The articles that have nuclear subject in the Mexican Constitution are 25, 27 and 28. At the same hierarchical level as the Constitution is the international treaties signed and ratified by our country, such as for example the Nuclear Safety Convention or the Convention on the Nuclear Materials Physical Protection. For the treaties negotiation process consists of a text adoption, the authentication which implies the final content signature and unalterable, the Senate approval and the consent submission, which implies the ratification and publication in the Federation Official Gazette. In the case of Mexican laws your proposition process includes an initiative, the analysis of the relevant committee, the discussion, approval, sanction, and with it the publication of the initiation force. The road can become very convoluted because some steps are recurrent, returning to the same level several times. Regulations whose purpose is to clarify, develop or explain the general principles contained in the laws that relate to more obtainable your application are subject to a similarly complicated process. First we developed a preliminary draft by the competent authority subject to revision and opinion of the respective institutions prior to submission to the Federal Executive. The final document is submitted to the latter project, which must be approved by the agencies involved, approved by the Federal Executive and finally published in the Federation Official Gazette, from which it launched its application. (Author)
A mathematical framework for reducing the domain in the mechanical analysis of periodic structures
De Carvalho, N V; Robinson, P
2010-01-01
A theoretical framework is developped leading to a sound derivation of Periodic Boundary Conditions (PBCs) for the analysis of domains smaller then the Unit Cells (UCs), named reduced Unit Cells (rUCs), by exploiting non-orthogonal translations and symmetries. A particular type of UCs, Offset-reduced Unit Cells (OrUCs) are highlighted. These enable the reduction of the analysis domain of the traditionally defined UCs without any loading restriction. The relevance of the framework and its application to any periodic structure is illustrated through two practical examples: 3D woven and honeycomb.
Working Memory and Language: Skill-Specific or Domain-General Relations to Mathematics?
Purpura, David J.; Ganley, Colleen M.
2014-01-01
Children's early mathematics skills develop in a cumulative fashion; foundational skills form a basis for the acquisition of later skills. However, non-mathematical factors such as working memory and language skills have also been linked to mathematical development at a broad level. Unfortunately, little research has been conducted to evaluate the…
Park, Ji Yong; Nuntrakune, Tippawan
2013-01-01
The Thailand education reform adopted cooperative learning to improve the quality of education. However, it has been reported that the introduction and maintenance of cooperative learning has been difficult and uncertain because of the cultural differences. The study proposed a conceptual framework developed based on making a connection between…
Development of a Mathematical Framework for Comparison of Underlay and Overlay Systems
Directory of Open Access Journals (Sweden)
SayedPouriaTalebi
2013-01-01
Full Text Available Overlay and underlayare two main spectrum access strategies in cognitive radio.In this work, wehave driven closed form expressions for the primary service outage probabilitiesof both techniques. We have also formulated and solved optimization problems with the objective of maximizing the secondary service’s capacity with constraints on primary service’s outage probability and secondary service power budget. A mathematical frame work for comparing the performance of the two systems has been developed. The performances of the two systems havebeen compared against different levels of primary service interference, activity, and secondary service power budget levels, and the strengths of each system has been clarified
Quantum kinematics on q-deformed quantum spaces I, Mathematical Framework
Wachter, H
2006-01-01
The aim of these two papers (I and II) is to try to give fundamental concepts of quantum kinematics to q-deformed quantum spaces. Paper I introduces the relevant mathematical concepts. A short review of the basic ideas of q-deformed analysis is given. These considerations are continued by introducing q-deformed analogs of Fourier transformations and delta functions. Their properties are discussed in detail. Furthermore, q-deformed versions of sesquilinear forms are defined, their basic properties are derived, and q-analogs of the Fourier-Plancherel identity are proved. In paper II these reasonings are applied to wave functions on position and momentum space.
Broom, Mark; Rychtář, Jan
2012-06-07
Recently, models of evolution have begun to incorporate structured populations, including spatial structure, through the modelling of evolutionary processes on graphs (evolutionary graph theory). One limitation of this otherwise quite general framework is that interactions are restricted to pairwise ones, through the edges connecting pairs of individuals. Yet, many animal interactions can involve many players, and theoretical models also describe such multiplayer interactions. We shall discuss a more general modelling framework of interactions of structured populations with the focus on competition between territorial animals, where each animal or animal group has a "home range" which overlaps with a number of others, and interactions between various group sizes are possible. Depending upon the behaviour concerned we can embed the results of different evolutionary games within our structure, as occurs for pairwise games such as the Prisoner's Dilemma or the Hawk-Dove game on graphs. We discuss some examples together with some important differences between this approach and evolutionary graph theory.
A general discrete-time modeling framework for animal movement using multistate random walks
McClintock, B.T.; King, R; Thomas, L.; Matthiopoulos, J.; McConnell, B.J.; Morales, J.M.
2012-01-01
Recent developments in animal tracking technology have permitted the collection of detailed data on the movement paths of individuals from many species. However, analysis methods for these data have not developed at a similar pace, largely due to a lack of suitable candidate models, coupled with the technical difficulties of fitting such models to data. To facilitate a general modeling framework, we propose that complex movement paths can be conceived as a series of movement strategies among ...
A Heuristic Evaluation of the Generalized Intelligent Framework for Tutoring (GIFT) Authoring Tools
2016-03-01
reuse and interoperability through standards. These goals were considered in the heuristic analysis of the authoring experience for GIFT users. 1.2...evaluations will be needed periodically as the technical goals are achieved as delineated in the research outlines that follow. • ARL Special Report...ARL-SR-0353 ● MAR 2016 US Army Research Laboratory A Heuristic Evaluation of the Generalized Intelligent Framework for Tutoring
A general framework for the solvatochromism of pyridinium phenolate betaine dyes
Rezende, Marcos Caroli; Aracena, Andrés
2013-02-01
A general framework for the solvatochromic behavior of pyridinium phenolate betaine dyes is presented, based on the variations with the medium of the electrophilic Fukui functions of their electron-pair donor and acceptor moieties. The model explains the ‘anomalous' solvatochromic behavior of large betaines, which change their behavior from negative to inverted, when electron-pair donor and acceptor groups are separated by a conjugated chain of variable size.
Mestrovic, A.; Stanicic, Z.; Hadziabdic, M. O.; Mucalo, I.; Bates, I.; Duggan, C; Carter, S; Bruno, A.
2011-01-01
Objectives. To assess Croatian community pharmacists' patient care competencies using the General Level Framework (GLF). Methods. The competencies of 100 community pharmacists working in 38 community pharmacies were evaluated using an adapted version of the GLF. Results. Pharmacists demonstrated the best performance in the competency areas drug specific issues and provision of drug products; the poorest performance was in the competency areas evaluation of outcomes and monitoring drug therapy...
Wachter, H
2007-01-01
The aim of these three papers (I, II, and III) is to develop a q-deformed version of non-relativistic Schroedinger theory. Paper I introduces the fundamental mathematical and physical concepts. The braided line and the three-dimensional q-deformed Euclidean space play the role of position space. For both cases the algebraic framework is extended by a time element. A short review of the elements of q-deformed analysis on the spaces under consideration is given. The time evolution operator is introduced in a consistent way and its basic properties are discussed. These reasonings are continued by proposing q-deformed analogs of the Schroedinger and the Heisenberg picture.
Schertzer, D. J.; Tchiguirinskaia, I.; Lovejoy, S.
2013-12-01
Fractals and multifractals are very illustrative of the profound synergies between mathematics and geophysics. The book ';Fractal Geometry of Nature' (Mandelbrot, 1982) brilliantly demonstrated the genericity in geophysics of geometric forms like Cantor set, Peano curve and Koch snowflake, which were once considered as mathematical monsters. However, to tame the geophysical monsters (e.g. extreme weather, floods, earthquakes), it was required to go beyond geometry and a unique fractal dimension. The concept of multifractal was coined in the course of rather theoretical debates on intermittency in hydrodynamic turbulence, sometimes with direct links to atmospheric dynamics. The latter required a generalized notion of scale in order to deal both with scale symmetries and strong anisotropies (e.g. time vs. space, vertical vs. horizontal). It was thus possible to show that the consequences of intermittency are of first order, not just 'corrections' with respect to the classical non-intermittent modeling. This was in fact a radical paradigm shift for geophysics: the extreme variability of geophysical fields over wide ranges of scale, which had long been so often acknowledged and deplored, suddenly became handy. Recent illustrations are the possibility to track down in large date sets the Higgs boson of intermittence, i.e. a first order multifractal phase transition leading to self-organized criticality, and to simulate intermittent vector fields with the help of Lie cascades, based for instance on random Clifford algebra. It is rather significant that this revolution is no longer limited to fundamental and theoretical problems of geophysics, but now touches many applications including environmental management, in particular for urban management and resilience. These applications are particularly stimulating when taken in their full complexity.
GNSS-ISR data fusion: General framework with application to the high-latitude ionosphere
Semeter, Joshua; Hirsch, Michael; Lind, Frank; Coster, Anthea; Erickson, Philip; Pankratius, Victor
2016-03-01
A mathematical framework is presented for the fusion of electron density measured by incoherent scatter radar (ISR) and total electron content (TEC) measured using global navigation satellite systems (GNSS). Both measurements are treated as projections of an unknown density field (for GNSS-TEC the projection is tomographic; for ISR the projection is a weighted average over a local spatial region) and discrete inverse theory is applied to obtain a higher fidelity representation of the field than could be obtained from either modality individually. The specific implementation explored herein uses the interpolated ISR density field as initial guess to the combined inverse problem, which is subsequently solved using maximum entropy regularization. Simulations involving a dense meridional network of GNSS receivers near the Poker Flat ISR demonstrate the potential of this approach to resolve sub-beam structure in ISR measurements. Several future directions are outlined, including (1) data fusion using lower level (lag product) ISR data, (2) consideration of the different temporal sampling rates, (3) application of physics-based regularization, (4) consideration of nonoptimal observing geometries, and (5) use of an ISR simulation framework for optimal experiment design.
National Service Frameworks and UK general practitioners: street-level bureaucrats at work?
Checkland, Kath
2004-11-01
This paper argues that the past decade has seen significant changes in the nature of medical work in general practice in the UK. Increasing pressure to use normative clinical guidelines and the move towards explicit quantitative measures of performance together have the potential to alter the way in which health care is delivered to patients. Whilst it is possible to view these developments from the well-established sociological perspectives of deprofessionalisation and proletarianisation, this paper takes a view of general practice as work, and uses the ideas of Lipsky to analyse practice-level responses to some of these changes. In addition to evidence-based clinical guidelines, National Service Frameworks, introduced by the UK government in 1997, also specify detailed models of service provision that health care providers are expected to follow. As part of a larger study examining the impact of National Service Frameworks in general practice, the response of three practices to the first four NSFs were explored. The failure of NSFs to make a significant impact is compared to the practices' positive responses to purely clinical guidelines such as those developed by the British Hypertension Society. Lipsky's concept of public service workers as 'street-level bureaucrats' is discussed and used as a framework within which to view these findings.
Aduenko, Alexander A.; Murray, Andy; Mendoza-Cortes, Jose L.
2014-01-01
In this paper we present an approach for the generalization of adsorption of light gases in crystalline porous materials. Our approach allows the determination of gas uptake considering only geometrical constrains of the porous framework and interaction energy of the guest molecule with the framework. The derivation of this general equation for the uptake of any crystalline porous framework is presented. Based on this theory, we calculated optimal values for the adsorption enthalpy at differe...
Working memory and language: skill-specific or domain-general relations to mathematics?
Purpura, David J; Ganley, Colleen M
2014-06-01
Children's early mathematics skills develop in a cumulative fashion; foundational skills form a basis for the acquisition of later skills. However, non-mathematical factors such as working memory and language skills have also been linked to mathematical development at a broad level. Unfortunately, little research has been conducted to evaluate the specific relations of these two non-mathematical factors to individual aspects of early mathematics. Thus, the focus of this study was to determine whether working memory and language were related to only individual aspects of early mathematics or related to many components of early mathematics skills. A total of 199 4- to 6-year-old preschool and kindergarten children were assessed on a battery of early mathematics tasks as well as measures of working memory and language. Results indicated that working memory has a specific relation to only a few-but critically important-early mathematics skills and language has a broad relation to nearly all early mathematics skills. Copyright © 2014 Elsevier Inc. All rights reserved.
A mathematical programming framework for early stage design of wastewater treatment plants
DEFF Research Database (Denmark)
Bozkurt, Hande; Quaglia, Alberto; Gernaey, Krist
2015-01-01
a process flow diagram. Towards this end, a superstructure approach is used to represent the treatment alternatives for reaction and separation. A generic process interval model is used to describe each alternative in terms of inputeoutput mass balances including conversion and separation factors. Next......The increasing number of alternative wastewater treatment technologies and stricter effluent requirements make the optimal treatment process selection for wastewater treatment plant design a complicated problem. This task, defined as wastewater treatment process synthesis, is currently based...... on expert decisions and previous experiences. This paper proposes a new approach based on mathematical programming to manage the complexity of the problem. The approach generates/identifies novel and optimal wastewater treatment process selection, and the interconnection between unit operations to create...
Li, Hongru; Wang, Yukui; Wang, Bing; Sun, Jian; Li, Yaolong
2017-01-01
Bearing performance degradation assessment is a key step of condition-based maintenance. In this paper, a novel indicator of bearing performance degradation assessment is presented based on the mathematical morphology (MM) theory for higher efficiency. Because the traditional mathematical morphology particle (MMP) is unable to exactly describe the bearing's performance degradation, we extended its definition to the general space to address the limited ability of the former definition. On the basis of the innovative definition, we used the morphology erosion operation instead of the morphology open operation to calculate the general mathematical morphology particle (GMMP) of the bearing's whole life data. The analysis of the simulation and practical application demonstrated that the proposed index is feasible and effective to indicate the performance degradation of the bearing.
Out-of-band emission suppression techniques based on a generalized OFDM framework
You, Zihao; Fang, Juan; Lu, I.-Tai
2014-12-01
Orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) systems suffer from the large out-of-band emission (OOBE) that may interfere with other users. Since most existing OFDM OOBE suppression schemes are derived on the base of an original OFDM system without any other scheme, we first propose a generalized OFDM framework that is capable of describing these schemes no matter whether any one or more of the schemes is applied. Then, according to the place where these schemes are implemented in our framework, they are classified into three groups, namely symbol mapping techniques, precoding techniques, and time-domain techniques. Finally, based on the proposed framework, we propose three new schemes by combining a precoding scheme named singular value decomposition (SVD) precoding with three other schemes from the three groups, namely spectral precoding, N-continuous symbol mapping, and filtering. Numerical results show the power spectral density (PSD), peak-to-average power ratio (PAPR), and bit error rate (BER) performances of the three proposed schemes. Since the individual schemes have complementary characteristics, the three proposed combined schemes are constructed to maintain the merits and avoid the drawbacks of the individual schemes involved. Thus, it is demonstrated that the proposed framework can be employed to develop other new combined OOBE suppression schemes tailoring to some specific practical needs.
Directory of Open Access Journals (Sweden)
Liu Cong
2011-12-01
Full Text Available Abstract Background Elucidating the effects of drugs on solid tumours is a highly challenging multi-level problem, since this involves many complexities associated with transport and cellular response, which in turn is characterized by highly non-linear chemical signal transduction. Appropriate systems frameworks are needed to seriously address the sources of these complexities, especially from the cellular side. Results We develop a skeletal modelling framework incorporating interstitial drug transport, intracellular signal processing and cell population descriptions. The descriptions aim to appropriately capture the nature of information flow. The model is deliberately formulated to start with simple intracellular descriptions so that additional features can be incorporated in a modular fashion. Two kinds of intracellular signalling modules which describe the drug effect were considered, one a monostable switch and the other a bistable switch. Analysis of our model revealed how different drug stimuli can lead to cell killing in the tumour. Interestingly both modules considered exhibited similar trends. The effects of important parameters were also studied. Conclusions We have created a predictive systems platform integrating drug transport and cellular response which can be systematically augmented to include additional layers of cellular complexity. Our results indicate that intracellular signalling models which are qualitatively different can give rise to similar behaviour to simple (and typical stimuli, and that validating intracellular descriptions must be performed with care by considering a variety of drug stimuli.
Stieha, Vicki; Shadle, Susan E.; Paterson, Sharon
2016-01-01
Evidence-based instructional practices (ebips) have been associated with positive student outcomes; however, institutions struggle to catalyze widespread adoption of these practices in general education science, technology, engineering, and mathematics (stem) courses. Further, linking ebips with integrated learning assessment is rarely discussed…
New Avenues for History in Mathematics Education: Mathematical Competencies and Anchoring
DEFF Research Database (Denmark)
Jankvist, U. T.; Kjeldsen, T. H.
2011-01-01
The paper addresses the apparent lack of impact of ‘history in mathematics education’ in mathematics education research in general, and proposes new avenues for research. We identify two general scenarios of integrating history in mathematics education that each gives rise to different problems....... The first scenario occurs when history is used as a ‘tool’ for the learning and teaching of mathematics, the second when history of mathematics as a ‘goal’ is pursued as an integral part of mathematics education. We introduce a multiple-perspective approach to history, and suggest that research on history...... in mathematics education follows one of two different avenues in dealing with these scenarios. The first is to focus on students’ development of mathematical competencies when history is used a tool for the learning of curriculum-dictated mathematical in-issues. A framework for this is described. Secondly, when...
A Generalized Mathematical Model for the Fracture Problem of the Suspended Highway
Directory of Open Access Journals (Sweden)
Zhao Ying
2017-01-01
Full Text Available In order to answer dangling fracture problems of highway, the suspended pavement equivalent for non - suspended pavement, through the special boundary conditions has been suspended highway stress field of expression, in accordance with the 3D fracture model of crack formation, and establish a vacant, a general mathematics model for fracture problems of highway and analysis in highway suspended segment weight and vehicle load limit of highway capacity of Pu For overturning road inPu is less than the force of carrying more than compared to the work and fruit Bridge Hydropower Station Road engineering examples to verify suspended highway should force field expressions for the correctness and applicability. The results show that: when the hanging ratio R 0. 243177 limits of Pu design axle load 100kN. When the vertical crack in the vacant in the direction of length greater than 0. 1, the ultimate bearing capacity is less than the design axle load 100kN; when the hanging ratio R is less than 0. 5, the road to local fracture, the ultimate bearing capacity of suspended stress field expressions in solution; when the hanging ratio is greater than or equal to 0. 5, the road does not reach the limit bearing capacity of the whole body; torque shear surface of the effect is far less than the bending moments on shear planes.
P-V criticality of AdS black holes in a general framework
Majhi, Bibhas Ranjan
2016-01-01
Interpreting the cosmological constant as pressure, it has been observed that AdS black holes behave as van der Waals system. The critical exponents for the phase transition for all AdS black holes are exactly same as those for the van der Waals system. Till now this has been observed case by case. Here, without using any specific form of the black hole metric, we present a general framework based on just two universal inputs. These are the general forms of the Smarr formula and the first law of thermodynamics. We find that the same values of the critical exponents can be obtained by this general analysis. Therefore there is no need to investigate for a particular metric. The importance of our analysis is that it highlights the observed universality, as well as revels the reason for such universality.
Energy Technology Data Exchange (ETDEWEB)
Bompard, E. [Dipartimento di Ingegneria Elettrica, Politecnico di Torino, I-10129 Torino (Italy)], E-mail: ettore.bompard@polito.it; Napoli, R.; Xue, F. [Dipartimento di Ingegneria Elettrica, Politecnico di Torino, I-10129 Torino (Italy)
2009-06-15
In the analysis of power systems security, recently a new concern related to possible malicious attacks caught much attention. Coordination among different transmission system operators (TSO) in an interconnected power system to counteract such attacks has become an important problem. This paper presents a general framework for describing the physical, cyber and decision-making aspects of the problem and their interrelations; within this framework, an analytic tool for the assessment of information impacts in handling on-line security after a malicious attack is proposed and discussed. The model is based on the socially rational multi-agent systems and the equilibrium of a fictitious play is considered to analyze the impacts of various levels of information available to the interconnected system operators on the outcomes of the decision-making process under attack. A 34-buses test system, with 3 systems interconnected by tie-lines, is presented to illustrate the model and compare the impacts of different information scenarios.
A general framework for analyzing sustainability of social-ecological systems.
Ostrom, Elinor
2009-07-24
A major problem worldwide is the potential loss of fisheries, forests, and water resources. Understanding of the processes that lead to improvements in or deterioration of natural resources is limited, because scientific disciplines use different concepts and languages to describe and explain complex social-ecological systems (SESs). Without a common framework to organize findings, isolated knowledge does not cumulate. Until recently, accepted theory has assumed that resource users will never self-organize to maintain their resources and that governments must impose solutions. Research in multiple disciplines, however, has found that some government policies accelerate resource destruction, whereas some resource users have invested their time and energy to achieve sustainability. A general framework is used to identify 10 subsystem variables that affect the likelihood of self-organization in efforts to achieve a sustainable SES.
A Parallel General Purpose Mulit-Objective Optimization Framework, with Application to Beam Dynamics
Ineichen, Y; Kolano, A; Bekas, C; Curioni, A; Arbenz, P
2013-01-01
Particle accelerators are invaluable tools for research in the basic and applied sciences, in fields such as materials science, chemistry, the biosciences, particle physics, nuclear physics and medicine. The design, commissioning, and operation of accelerator facilities is a non-trivial task, due to the large number of control parameters and the complex interplay of several conflicting design goals. We propose to tackle this problem by means of multi-objective optimization algorithms which also facilitate a parallel deployment. In order to compute solutions in a meaningful time frame we require a fast and scalable software framework. In this paper, we present the implementation of such a general-purpose framework for simulation based multi-objective optimization methods that allows the automatic investigation of optimal sets of machine parameters. The implementation is based on a master/slave paradigm, employing several masters that govern a set of slaves executing simulations and performing optimization task...
Western Canadian Protocol for Collaboration in Basic Education, Edmonton (Alberta).
This annotated bibliography identifies French language resources endorsed for the K-12 grade levels by all Western Canadian Protocol (WCP) jurisdictions implementing the Common Curriculum Framework for K- 12 Mathematics. Resources were selected through a collaborative review process based on their high level of fidelity with the rationale,…
Schulte, R.P.O.
2003-01-01
The analysis of the intrinsic properties and processes of ecosystems, which regulate the production stability of mixed grasslands, has been complicated by the environmental noise caused by stochastic weather fluctuations. A mathematical framework is presented to deduct the actual, the extrinsic and
Fraser, Virginia; Garofalo, Joe
2015-01-01
The purpose of this study was to describe how and why novice mathematics teachers incorporated technology-generated representations in their instruction. The participants in the study were graduates of a technology-rich mathematics teacher educator program. The teachers were interviewed at the beginning and end of the study concerning their…
A General-purpose Framework for Parallel Processing of Large-scale LiDAR Data
Li, Z.; Hodgson, M.; Li, W.
2016-12-01
Light detection and ranging (LiDAR) technologies have proven efficiency to quickly obtain very detailed Earth surface data for a large spatial extent. Such data is important for scientific discoveries such as Earth and ecological sciences and natural disasters and environmental applications. However, handling LiDAR data poses grand geoprocessing challenges due to data intensity and computational intensity. Previous studies received notable success on parallel processing of LiDAR data to these challenges. However, these studies either relied on high performance computers and specialized hardware (GPUs) or focused mostly on finding customized solutions for some specific algorithms. We developed a general-purpose scalable framework coupled with sophisticated data decomposition and parallelization strategy to efficiently handle big LiDAR data. Specifically, 1) a tile-based spatial index is proposed to manage big LiDAR data in the scalable and fault-tolerable Hadoop distributed file system, 2) two spatial decomposition techniques are developed to enable efficient parallelization of different types of LiDAR processing tasks, and 3) by coupling existing LiDAR processing tools with Hadoop, this framework is able to conduct a variety of LiDAR data processing tasks in parallel in a highly scalable distributed computing environment. The performance and scalability of the framework is evaluated with a series of experiments conducted on a real LiDAR dataset using a proof-of-concept prototype system. The results show that the proposed framework 1) is able to handle massive LiDAR data more efficiently than standalone tools; and 2) provides almost linear scalability in terms of either increased workload (data volume) or increased computing nodes with both spatial decomposition strategies. We believe that the proposed framework provides valuable references on developing a collaborative cyberinfrastructure for processing big earth science data in a highly scalable environment.
Mathematical Methods of Game and Economic Theory
Aubin, J-P
1982-01-01
This book presents a unified treatment of optimization theory, game theory and a general equilibrium theory in economics in the framework of nonlinear functional analysis. It not only provides powerful and versatile tools for solving specific problems in economics and the social sciences but also serves as a unifying theme in the mathematical theory of these subjects as well as in pure mathematics itself.
General framework for dynamic large deformation contact problems based on phantom-node X-FEM
Broumand, P.; Khoei, A. R.
2017-08-01
This paper presents a general framework for modeling dynamic large deformation contact-impact problems based on the phantom-node extended finite element method. The large sliding penalty contact formulation is presented based on a master-slave approach which is implemented within the phantom-node X-FEM and an explicit central difference scheme is used to model the inertial effects. The method is compared with conventional contact X-FEM; advantages, limitations and implementational aspects are also addressed. Several numerical examples are presented to show the robustness and accuracy of the proposed method.
RosettaRemodel: a generalized framework for flexible backbone protein design.
Directory of Open Access Journals (Sweden)
Po-Ssu Huang
Full Text Available We describe RosettaRemodel, a generalized framework for flexible protein design that provides a versatile and convenient interface to the Rosetta modeling suite. RosettaRemodel employs a unified interface, called a blueprint, which allows detailed control over many aspects of flexible backbone protein design calculations. RosettaRemodel allows the construction and elaboration of customized protocols for a wide range of design problems ranging from loop insertion and deletion, disulfide engineering, domain assembly, loop remodeling, motif grafting, symmetrical units, to de novo structure modeling.
Implementation of a PETN failure model using ARIA's general chemistry framework
Energy Technology Data Exchange (ETDEWEB)
Hobbs, Michael L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2017-01-01
We previously developed a PETN thermal decomposition model that accurately predicts thermal ignition and detonator failure [1]. This model was originally developed for CALORE [2] and required several complex user subroutines. Recently, a simplified version of the PETN decomposition model was implemented into ARIA [3] using a general chemistry framework without need for user subroutines. Detonator failure was also predicted with this new model using ENCORE. The model was simplified by 1) basing the model on moles rather than mass, 2) simplifying the thermal conductivity model, and 3) implementing ARIA’s new phase change model. This memo briefly describes the model, implementation, and validation.
A Framework and Mathematical Modeling for the Vehicular Delay Tolerant Network Routing
Directory of Open Access Journals (Sweden)
Mostofa Kamal Nasir
2016-01-01
Full Text Available Vehicular ad hoc networks (VANETs are getting growing interest as they are expected to play crucial role in making safer, smarter, and more efficient transportation networks. Due to unique characteristics such as sparse topology and intermittent connectivity, Delay Tolerant Network (DTN routing in VANET becomes an inherent choice and is challenging. However, most of the existing DTN protocols do not accurately discover potential neighbors and, hence, appropriate intermediate nodes for packet transmission. Moreover, these protocols cause unnecessary overhead due to excessive beacon messages. To cope with these challenges, this paper presents a novel framework and an Adaptive Geographical DTN Routing (AGDR for vehicular DTNs. AGDR exploits node position, current direction, speed, and the predicted direction to carefully select an appropriate intermediate node. Direction indicator light is employed to accurately predict the vehicle future direction so that the forwarding node can relay packets to the desired destination. Simulation experiments confirm the performance supremacy of AGDR compared to contemporary schemes in terms of packet delivery ratio, overhead, and end-to-end delay. Simulation results demonstrate that AGDR improves the packet delivery ratio (5–7%, reduces the overhead (1–5%, and decreases the delay (up to 0.02 ms. Therefore, AGDR improves route stability by reducing the frequency of route failures.
Hassinger-Das, Brenna; Jordan, Nancy C; Glutting, Joseph; Irwin, Casey; Dyson, Nancy
2014-02-01
Domain-general skills that mediate the relation between kindergarten number sense and first-grade mathematics skills were investigated. Participants were 107 children who displayed low number sense in the fall of kindergarten. Controlling for background variables, multiple regression analyses showed that both attention problems and executive functioning were unique predictors of mathematics outcomes. Attention problems were more important for predicting first-grade calculation performance, whereas executive functioning was more important for predicting first-grade performance on applied problems. Moreover, both executive functioning and attention problems were unique partial mediators of the relationship between kindergarten and first-grade mathematics skills. The results provide empirical support for developing interventions that target executive functioning and attention problems in addition to instruction in number skills for kindergartners with initial low number sense. Copyright © 2013 Elsevier Inc. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Alexander S. Rattner; Donna Post Guillen; Alark Joshi
2012-12-01
Photo- and physically-realistic techniques are often insufficient for visualization of simulation results, especially for 3D and time-varying datasets. Substantial research efforts have been dedicated to the development of non-photorealistic and illustration-inspired visualization techniques for compact and intuitive presentation of such complex datasets. While these efforts have yielded valuable visualization results, a great deal of work has been reproduced in studies as individual research groups often develop purpose-built platforms. Additionally, interoperability between illustrative visualization software is limited due to specialized processing and rendering architectures employed in different studies. In this investigation, a generalized framework for illustrative visualization is proposed, and implemented in marmotViz, a ParaView plugin, enabling its use on variety of computing platforms with various data file formats and mesh geometries. Detailed descriptions of the region-of-interest identification and feature-tracking algorithms incorporated into this tool are provided. Additionally, implementations of multiple illustrative effect algorithms are presented to demonstrate the use and flexibility of this framework. By providing a framework and useful underlying functionality, the marmotViz tool can act as a springboard for future research in the field of illustrative visualization.
General framework of the non-perturbative renormalization group for non-equilibrium steady states
Energy Technology Data Exchange (ETDEWEB)
Canet, Leonie [Laboratoire de Physique et Modelisation des Milieux Condenses, Universite Joseph Fourier Grenoble I-CNRS, BP166, 38042 Grenoble Cedex (France); Chate, Hugues [Service de Physique de l' Etat Condense, CEA-Saclay, 91191 Gif-sur-Yvette Cedex (France); Delamotte, Bertrand, E-mail: leonie.canet@grenoble.cnrs.fr [Laboratoire de Physique Theorique de la Matiere Condensee, Universite Pierre et Marie Curie, Paris VI, CNRS UMR 7600, 4 Place Jussieu, 75252 Paris Cedex 05 (France)
2011-12-09
This paper is devoted to presenting in detail the non-perturbative renormalization group (NPRG) formalism to investigate out-of-equilibrium systems and critical dynamics in statistical physics. The general NPRG framework for studying non-equilibrium steady states in stochastic models is expounded and fundamental technicalities are stressed, mainly regarding the role of causality and of It o-bar 's discretization. We analyze the consequences of It o-bar 's prescription in the NPRG framework and eventually provide an adequate regularization to encode them automatically. Besides, we show how to build a supersymmetric NPRG formalism with emphasis on time-reversal symmetric problems, whose supersymmetric structure allows for a particularly simple implementation of NPRG in which causality issues are transparent. We illustrate the two approaches on the example of Model A within the derivative expansion approximation at order 2 and check that they yield identical results. We stress, though, that the framework presented here also applies to genuinely out-of-equilibrium problems. (paper)
General framework for estimating the ultimate precision limit in noisy quantum-enhanced metrology
Escher, B M; Davidovich, L; 10.1038/nphys1958
2012-01-01
The estimation of parameters characterizing dynamical processes is central to science and technology. The estimation error changes with the number N of resources employed in the experiment (which could quantify, for instance, the number of probes or the probing energy). Typically, it scales as 1/N^(1/2). Quantum strategies may improve the precision, for noiseless processes, by an extra factor 1/N^(1/2). For noisy processes, it is not known in general if and when this improvement can be achieved. Here we propose a general framework for obtaining attainable and useful lower bounds for the ultimate limit of precision in noisy systems. We apply this bound to lossy optical interferometry and atomic spectroscopy in the presence of dephasing, showing that it captures the main features of the transition from the 1/N to the 1/N^(1/2) behaviour as N increases, independently of the initial state of the probes, and even with use of adaptive feedback.
General Framework and Advanced Information Theoretical Results on Eigenmode MIMO Channel Inversion
Directory of Open Access Journals (Sweden)
J. Sykora
2005-09-01
Full Text Available This paper provides general and deep investigation of adaptationstrategies based on the channel inversion policy regarding wide varietyof channel modes. Our novel approach to the eigenmode space MIMOchannel inversion policy relies on the eigenmode space reductionproviding zero transmission outage probability regardless of theinstantaneous channel fading realization. Very detailed survey of thefeatures of channel capacity is provided in analytical closed formexpressions supported by many particular numerical results (Alamoutischeme is included. The correlated MIMO channel is involved into ourtreatment as well. We also address the trade-off between the capacityand transmission outage probability. The novel results are developed inthe general framework with exhaustive summary of well known SISO andSIMO results.
Traxl, Dominik; Kurths, Jürgen
2016-01-01
Network theory has proven to be a powerful tool in describing and analyzing systems by modelling the relations between their constituent objects. In recent years great progress has been made by augmenting `traditional' network theory. However, existing network representations still lack crucial features in order to serve as a general data analysis tool. These include, most importantly, an explicit association of information with possibly heterogeneous types of objects and relations, and a conclusive representation of the properties of groups of nodes as well as the interactions between such groups on different scales. In this paper, we introduce a collection of definitions resulting in a framework that, on the one hand, entails and unifies existing network representations (e.g., network of networks, multilayer networks), and on the other hand, generalizes and extends them by incorporating the above features. To implement these features, we first specify the nodes and edges of a finite graph as sets of propert...
Aerts, Diederik
2015-01-01
Ambiguity and ambiguity aversion have been widely studied in decision theory and economics both at a theoretical and an experimental level. After Ellsberg's seminal studies challenging subjective expected utility theory (SEUT), several (mainly normative) approaches have been put forward to reproduce ambiguity aversion and Ellsberg-type preferences. However, Machina and other authors have pointed out some fundamental difficulties of these generalizations of SEUT to cope with some variants of Ellsberg's thought experiments, which has recently been experimentally confirmed. Starting from our quantum modeling approach to human cognition, we develop here a general probabilistic framework to model human decisions under uncertainty. We show that our quantum theoretical model faithfully represents different sets of data collected on both the Ellsberg and the Machina paradox situations, and is flexible enough to describe different subjective attitudes with respect to ambiguity. Our approach opens the way toward a quan...
Kawai, Shinnosuke; Komatsuzaki, Tamiki
2010-12-21
A framework recently developed for the extraction of a dynamic reaction coordinate to mediate reactions buried in a multidimensional Langevin equation is extended to the generalized Langevin equations without a priori assumption of the forms of the potential (in general, nonlinearly coupled systems) and the friction kernel. The equation of motion with memory effect can be transformed into an equation without memory at the cost of an increase in the dimensionality of the system, and hence the theoretical framework developed for the (nonlinear) Langevin formulation can be generalized to the non-Markovian process with colored noise. It is found that the increased dimension can be physically interpreted as effective modes of the fluctuating environment. As an illustrative example, we apply this theory to a multidimensional generalized Langevin equation for motion on the Müller-Brown potential surface with an exponential friction kernel. Numerical simulations find a boundary between the highly reactive region and the less reactive region in the space of initial conditions. The location of the boundary is found to depend significantly on both the memory kernel and the nonlinear couplings. The theory extracts a reaction coordinate whose sign determines the fate of the reaction taking into account thermally fluctuating environments, memory effect, and nonlinearities. It is found that the location of the boundary of reactivity is satisfactorily reproduced as the zero of the statistical average of the new reaction coordinate, which is an analytical functional of both the original position coordinates and velocities of the system, and of the properties of the environment.
Directory of Open Access Journals (Sweden)
James M McCaw
2011-04-01
Full Text Available We present a method to measure the relative transmissibility ("transmission fitness" of one strain of a pathogen compared to another. The model is applied to data from "competitive mixtures" experiments in which animals are co-infected with a mixture of two strains. We observe the mixture in each animal over time and over multiple generations of transmission. We use data from influenza experiments in ferrets to demonstrate the approach. Assessment of the relative transmissibility between two strains of influenza is important in at least three contexts: 1 Within the human population antigenically novel strains of influenza arise and compete for susceptible hosts. 2 During a pandemic event, a novel sub-type of influenza competes with the existing seasonal strain(s. The unfolding epidemiological dynamics are dependent upon both the population's susceptibility profile and the inherent transmissibility of the novel strain compared to the existing strain(s. 3 Neuraminidase inhibitors (NAIs, while providing significant potential to reduce transmission of influenza, exert selective pressure on the virus and so promote the emergence of drug-resistant strains. Any adverse outcome due to selection and subsequent spread of an NAI-resistant strain is exquisitely dependent upon the transmission fitness of that strain. Measurement of the transmission fitness of two competing strains of influenza is thus of critical importance in determining the likely time-course and epidemiology of an influenza outbreak, or the potential impact of an intervention measure such as NAI distribution. The mathematical framework introduced here also provides an estimate for the size of the transmitted inoculum. We demonstrate the framework's behaviour using data from ferret transmission studies, and through simulation suggest how to optimise experimental design for assessment of transmissibility. The method introduced here for assessment of mixed transmission events has
A general framework to learn surrogate relevance criterion for atlas based image segmentation
Zhao, Tingting; Ruan, Dan
2016-09-01
Multi-atlas based image segmentation sees great opportunities in the big data era but also faces unprecedented challenges in identifying positive contributors from extensive heterogeneous data. To assess data relevance, image similarity criteria based on various image features widely serve as surrogates for the inaccessible geometric agreement criteria. This paper proposes a general framework to learn image based surrogate relevance criteria to better mimic the behaviors of segmentation based oracle geometric relevance. The validity of its general rationale is verified in the specific context of fusion set selection for image segmentation. More specifically, we first present a unified formulation for surrogate relevance criteria and model the neighborhood relationship among atlases based on the oracle relevance knowledge. Surrogates are then trained to be small for geometrically relevant neighbors and large for irrelevant remotes to the given targets. The proposed surrogate learning framework is verified in corpus callosum segmentation. The learned surrogates demonstrate superiority in inferring the underlying oracle value and selecting relevant fusion set, compared to benchmark surrogates.
A general framework to learn surrogate relevance criterion for atlas based image segmentation.
Zhao, Tingting; Ruan, Dan
2016-09-07
Multi-atlas based image segmentation sees great opportunities in the big data era but also faces unprecedented challenges in identifying positive contributors from extensive heterogeneous data. To assess data relevance, image similarity criteria based on various image features widely serve as surrogates for the inaccessible geometric agreement criteria. This paper proposes a general framework to learn image based surrogate relevance criteria to better mimic the behaviors of segmentation based oracle geometric relevance. The validity of its general rationale is verified in the specific context of fusion set selection for image segmentation. More specifically, we first present a unified formulation for surrogate relevance criteria and model the neighborhood relationship among atlases based on the oracle relevance knowledge. Surrogates are then trained to be small for geometrically relevant neighbors and large for irrelevant remotes to the given targets. The proposed surrogate learning framework is verified in corpus callosum segmentation. The learned surrogates demonstrate superiority in inferring the underlying oracle value and selecting relevant fusion set, compared to benchmark surrogates.
Directory of Open Access Journals (Sweden)
Pedro Saa
2015-04-01
Full Text Available Kinetic models provide the means to understand and predict the dynamic behaviour of enzymes upon different perturbations. Despite their obvious advantages, classical parameterizations require large amounts of data to fit their parameters. Particularly, enzymes displaying complex reaction and regulatory (allosteric mechanisms require a great number of parameters and are therefore often represented by approximate formulae, thereby facilitating the fitting but ignoring many real kinetic behaviours. Here, we show that full exploration of the plausible kinetic space for any enzyme can be achieved using sampling strategies provided a thermodynamically feasible parameterization is used. To this end, we developed a General Reaction Assembly and Sampling Platform (GRASP capable of consistently parameterizing and sampling accurate kinetic models using minimal reference data. The former integrates the generalized MWC model and the elementary reaction formalism. By formulating the appropriate thermodynamic constraints, our framework enables parameterization of any oligomeric enzyme kinetics without sacrificing complexity or using simplifying assumptions. This thermodynamically safe parameterization relies on the definition of a reference state upon which feasible parameter sets can be efficiently sampled. Uniform sampling of the kinetics space enabled dissecting enzyme catalysis and revealing the impact of thermodynamics on reaction kinetics. Our analysis distinguished three reaction elasticity regions for common biochemical reactions: a steep linear region (0> ΔGr >-2 kJ/mol, a transition region (-2> ΔGr >-20 kJ/mol and a constant elasticity region (ΔGr <-20 kJ/mol. We also applied this framework to model more complex kinetic behaviours such as the monomeric cooperativity of the mammalian glucokinase and the ultrasensitive response of the phosphoenolpyruvate carboxylase of Escherichia coli. In both cases, our approach described appropriately not only
Mathematical Evidence-theoretic Framework for Information Fusion of Disaster Scene Big Data
Chen, Z.
2014-12-01
The remote sensing community and geospatial industries are embracing the paradigm of 'big data'. This trend is in one hand due to the fact that heterogeneous remote sensors are producing tremendous amounts of earth observation (EO) data every day; on the other hand it is aspired by the promise that big data computing may be the fourth paradigm for scientific discovery. Many traditional techniques have been developed and will continue to be useful to deal with earth-observation big data, for examples, pansharpening, fusion of data with different electromagnetic nature (e.g. color images and SAR images), and use of multi-sensor data for improved land-cover classification. However, two limitations are recognized for these techniques, which include: (1) first, these methods are tightly dependent on a two-dimensional grid scale; and (2) second, temporal, spatial and causal relations are not intelligently treated. These limitations render them insufficient when used to attack the emerging Disaster Scene Big Data (DSBD). DSBD emerges as a geological or climatic hazard unfolds into a disaster. In the example of an earthquake, disaster data starts accruing as the ground shaking is being monitored. Along the time scale, heterogeneous multi-sensor data arise: EO data with various electromagnetic nature, oblique images, airborne/terrestrial active (Lidar) data, and the recently emerged crowdsourcing data. Neither theoretical models nor effective methods exist to date that can sufficiently fuse these data towards revealing the 'ground-truth' of the disaster effects, for example, damage to built objects. This presentation will present an augmented evidence-theoretic framework based on the classical Dempster-Shafer theory. With a focus on reasoning the ground-truth of build-object damage, causal, correlational and relational evidences will be defined considering their temporal and spatial scales. The newly developed graph-based learning approach will be explored for estimating
Baugher, Mark W.
2012-01-01
The dissertation outlines a framework for understanding variation in ultimate attainment and syntactic structure in second language acquisition by positing a distinction between competence-based and generalized learning processes. Within this framework, competence-based learning is theorized to employ inductive learning processes to acquire a…
Baugher, Mark W.
2012-01-01
The dissertation outlines a framework for understanding variation in ultimate attainment and syntactic structure in second language acquisition by positing a distinction between competence-based and generalized learning processes. Within this framework, competence-based learning is theorized to employ inductive learning processes to acquire a…
Fossey, M.; Rousseau, A. N.; Savary, S.; Royer, A.
2014-12-01
Wetlands play a significant role on the hydrological cycle, reducing peak flows through water storage functions and sustaining low flows through slow release of water. However, their impacts on water resource availability and flood control are mainly driven by wetland types and locations within a watershed. So, despite the general agreement about these major hydrological functions, little is known about their spatial and typological influences. Consequently, assessing the quantitative impact of wetlands on hydrological regimes has become a relevant issue for both the scientific community and the decision-maker community. To investigate the hydrologic response at the watershed scale, mathematical modelling has been a well-accepted framework. Specific isolated and riparian wetland modules were implemented in the PHYSITEL/HYDROTEL distributed hydrological modelling platform to assess the impact of the spatial distribution of isolated and riparian wetlands on the stream flows of the Becancour River watershed, Quebec, Canada. More specifically, the focus was on assessing whether stream flow parameters, including peak flow, low flow and flow volume, were related to: (i) the percentage and the distribution of wetlands in the watershed, (ii) geographic location of wetlands, and (iii) seasons. Preliminary results suggest that: (i) integration of specific wetland modules can slightly improve HYDROTEL's ability to replicate basic hydrograph characteristics; and (ii) isolated and riparian wetlands have individual space- and time-dependent impacts on the hydrologic response of the study watershed.
Bhalla, Amneet Pal Singh; Bale, Rahul; Griffith, Boyce E.; Patankar, Neelesh A.
2013-10-01
Many problems of interest in biological fluid mechanics involve interactions between fluids and solids that require the coupled solution of momentum equations for both the fluid and the solid. In this work, we develop a mathematical framework and an adaptive numerical method for such fluid-structure interaction (FSI) problems in which the structure may be rigid, deforming, or elastic. We employ an immersed boundary (IB) formulation of the problem that permits us to avoid body conforming discretizations and to use fast Cartesian grid solvers. Rigidity and deformational kinematic constraints are imposed using a formulation based on distributed Lagrange multipliers, and a conventional IB method is used to describe the elasticity of the immersed body. We use Cartesian grid adaptive mesh refinement (AMR) to discretize the equations of motion and thereby obtain a solution methodology that efficiently captures thin boundary layers at fluid-solid interfaces as well as flow structures shed from such interfaces. This adaptive methodology is validated for several benchmark problems in two and three spatial dimensions. In addition, we use this scheme to simulate free swimming, including the maneuvering of a two-dimensional model eel and a three-dimensional model of the weakly electric black ghost knifefish.
Xenofontos, Constantinos; Papadopoulos, Christos,
2015-01-01
International audience; In this paper, we examine the ways the history of mathematics is integrated in the national textbooks of Cyprus and Greece. Our data-driven analyses suggest that the references identified can be clustered in four categories: (a) biographical references about mathematicians or historical references regarding the origins of a mathematical concept, (b) references to the history of a mathematical method or formula containing a solution or proof, (c) mathematical tasks of p...
A general science-based framework for dynamical spatio-temporal models
Wikle, C.K.; Hooten, M.B.
2010-01-01
Spatio-temporal statistical models are increasingly being used across a wide variety of scientific disciplines to describe and predict spatially-explicit processes that evolve over time. Correspondingly, in recent years there has been a significant amount of research on new statistical methodology for such models. Although descriptive models that approach the problem from the second-order (covariance) perspective are important, and innovative work is being done in this regard, many real-world processes are dynamic, and it can be more efficient in some cases to characterize the associated spatio-temporal dependence by the use of dynamical models. The chief challenge with the specification of such dynamical models has been related to the curse of dimensionality. Even in fairly simple linear, first-order Markovian, Gaussian error settings, statistical models are often over parameterized. Hierarchical models have proven invaluable in their ability to deal to some extent with this issue by allowing dependency among groups of parameters. In addition, this framework has allowed for the specification of science based parameterizations (and associated prior distributions) in which classes of deterministic dynamical models (e. g., partial differential equations (PDEs), integro-difference equations (IDEs), matrix models, and agent-based models) are used to guide specific parameterizations. Most of the focus for the application of such models in statistics has been in the linear case. The problems mentioned above with linear dynamic models are compounded in the case of nonlinear models. In this sense, the need for coherent and sensible model parameterizations is not only helpful, it is essential. Here, we present an overview of a framework for incorporating scientific information to motivate dynamical spatio-temporal models. First, we illustrate the methodology with the linear case. We then develop a general nonlinear spatio-temporal framework that we call general quadratic
Topics in mathematical physics, general relativity, and cosmology in honor of Jerzy Plebanski
Plebanski, Jerzy; Garcia-Compean, Hugo
. Maldacena. Yang-Mills type BRST and co-BRST algebra for Teleparallelism / E. W. Mielke & A. A. Rincon Maggiolo. The double role of Einstein's equations: as equations of motion and as vanishing energy-momentum tensor / M. Montesinos. Alternative elements in the Cayley-Dickson algebras / G. Moreno. Coherent state map and deformations of Moyal product / A. Odzijewicz. On uncertainty relations and states in deformation quantization / M. Przanowski & F. J. Turrubiates. On the Dirac-Infeld-Plebanski delta function / O. Rosas-Ortiz. Mathematical structures in perturbation quantum field theory / M. Rosenbaum. A note on the foundation of relativistic mechanics: covariant Hamiltonian general relativity / C. Rovelli. The Magnus series / L. Saenz & R. Suarez. Singular integral equation method for the construction of cylindrical wave solutions of the Einstein-Weyl equations / N. R. Sibgatullin, A. A. Garcia & V. S. Manko. Geometric POV-measures, pseudo-Kahlerian functions and time / M. Skulimowski. Teleparallelism, modified Born-Infeld nonlinearity and space-time as a micromorphic ether / J. J. Slawianowski. Einstein's intuition and the post-Newtonian approximation / J. Stachel. Deformation theory and physics model building / D. Sternheimer. Lanczos potentials via the HH formalism / G. F. Torres del Castillo. Spin foam model for 3D gravity in the continuum / J. A. Zapata -- pt. III. Informal part. Ecology of the Riemann tensor / B. Mielnik. Poem to Prof. Dr. Jerzy F. Plebanski / N. V. Mitskievich (Mickiewicz).
Directory of Open Access Journals (Sweden)
O. V. Fomin
2013-10-01
Full Text Available Purpose. Presentation of features and example of the use of the offered determination algorithm of optimum geometrical parameters for the components of freight cars on the basis of the generalized mathematical models, which is realized using computer. Methodology. The developed approach to search for optimal geometrical parameters can be described as the determination of optimal decision of the selected set of possible variants. Findings. The presented application example of the offered algorithm proved its operation capacity and efficiency of use. Originality. The determination procedure of optimal geometrical parameters for freight car components on the basis of the generalized mathematical models was formalized in the paper. Practical value. Practical introduction of the research results for universal open cars allows one to reduce container of their design and accordingly to increase the carrying capacity almost by100 kg with the improvement of strength characteristics. Taking into account the mass of their park this will provide a considerable economic effect when producing and operating. The offered approach is oriented to the distribution of the software packages (for example Microsoft Excel, which are used by technical services of the most enterprises, and does not require additional capital investments (acquisitions of the specialized programs and proper technical staff training. This proves the correctness of the research direction. The offered algorithm can be used for the solution of other optimization tasks on the basis of the generalized mathematical models.
Geary, David C; Nicholas, Alan; Li, Yaoran; Sun, Jianguo
2017-07-01
The contributions of domain-general abilities and domain-specific knowledge to subsequent mathematics achievement were longitudinally assessed (n = 167) through 8(th) grade. First grade intelligence and working memory and prior grade reading achievement indexed domain-general effects and domain-specific effects were indexed by prior grade mathematics achievement and mathematical cognition measures of prior grade number knowledge, addition skills, and fraction knowledge. Use of functional data analysis enabled grade-by-grade estimation of overall domain-general and domain-specific effects on subsequent mathematics achievement, the relative importance of individual domain-general and domain-specific variables on this achievement, and linear and non-linear across-grade estimates of these effects. The overall importance of domain-general abilities for subsequent achievement was stable across grades, with working memory emerging as the most important domain-general ability in later grades. The importance of prior mathematical competencies on subsequent mathematics achievement increased across grades, with number knowledge and arithmetic skills critical in all grades and fraction knowledge in later grades. Overall, domain-general abilities were more important than domain-specific knowledge for mathematics learning in early grades but general abilities and domain-specific knowledge were equally important in later grades.
Lenkiewicz, Przemyslaw; Shkaravska, Olha; Goosen, Twan; Broeder, Daan; Windhouwer, Menzo; Roth, Stephanie; Olsson, Olof; Chair), Nicoletta Calzolari (Conference; Choukri, Khalid; Declerck, Thierry; Loftsson, Hrafn; Maegaard, Bente; Mariani, Joseph; Moreno, Asuncion; Odijk, Jan; Piperidis, Stelios
2014-01-01
Researchers share large amounts of digital resources, which offer new chances for cooperation. Collaborative annotation systems are meant to support this. Often these systems are targeted at a specific task or domain, e.g., annotation of a corpus. The DWAN framework for web annotation is generic and
The Nature Index: a general framework for synthesizing knowledge on the state of biodiversity.
Directory of Open Access Journals (Sweden)
Grégoire Certain
Full Text Available The magnitude and urgency of the biodiversity crisis is widely recognized within scientific and political organizations. However, a lack of integrated measures for biodiversity has greatly constrained the national and international response to the biodiversity crisis. Thus, integrated biodiversity indexes will greatly facilitate information transfer from science toward other areas of human society. The Nature Index framework samples scientific information on biodiversity from a variety of sources, synthesizes this information, and then transmits it in a simplified form to environmental managers, policymakers, and the public. The Nature Index optimizes information use by incorporating expert judgment, monitoring-based estimates, and model-based estimates. The index relies on a network of scientific experts, each of whom is responsible for one or more biodiversity indicators. The resulting set of indicators is supposed to represent the best available knowledge on the state of biodiversity and ecosystems in any given area. The value of each indicator is scaled relative to a reference state, i.e., a predicted value assessed by each expert for a hypothetical undisturbed or sustainably managed ecosystem. Scaled indicator values can be aggregated or disaggregated over different axes representing spatiotemporal dimensions or thematic groups. A range of scaling models can be applied to allow for different ways of interpreting the reference states, e.g., optimal situations or minimum sustainable levels. Statistical testing for differences in space or time can be implemented using Monte-Carlo simulations. This study presents the Nature Index framework and details its implementation in Norway. The results suggest that the framework is a functional, efficient, and pragmatic approach for gathering and synthesizing scientific knowledge on the state of biodiversity in any marine or terrestrial ecosystem and has general applicability worldwide.
The Nature Index: a general framework for synthesizing knowledge on the state of biodiversity.
Certain, Grégoire; Skarpaas, Olav; Bjerke, Jarle-Werner; Framstad, Erik; Lindholm, Markus; Nilsen, Jan-Erik; Norderhaug, Ann; Oug, Eivind; Pedersen, Hans-Christian; Schartau, Ann-Kristin; van der Meeren, Gro I; Aslaksen, Iulie; Engen, Steinar; Garnåsjordet, Per-Arild; Kvaløy, Pål; Lillegård, Magnar; Yoccoz, Nigel G; Nybø, Signe
2011-04-22
The magnitude and urgency of the biodiversity crisis is widely recognized within scientific and political organizations. However, a lack of integrated measures for biodiversity has greatly constrained the national and international response to the biodiversity crisis. Thus, integrated biodiversity indexes will greatly facilitate information transfer from science toward other areas of human society. The Nature Index framework samples scientific information on biodiversity from a variety of sources, synthesizes this information, and then transmits it in a simplified form to environmental managers, policymakers, and the public. The Nature Index optimizes information use by incorporating expert judgment, monitoring-based estimates, and model-based estimates. The index relies on a network of scientific experts, each of whom is responsible for one or more biodiversity indicators. The resulting set of indicators is supposed to represent the best available knowledge on the state of biodiversity and ecosystems in any given area. The value of each indicator is scaled relative to a reference state, i.e., a predicted value assessed by each expert for a hypothetical undisturbed or sustainably managed ecosystem. Scaled indicator values can be aggregated or disaggregated over different axes representing spatiotemporal dimensions or thematic groups. A range of scaling models can be applied to allow for different ways of interpreting the reference states, e.g., optimal situations or minimum sustainable levels. Statistical testing for differences in space or time can be implemented using Monte-Carlo simulations. This study presents the Nature Index framework and details its implementation in Norway. The results suggest that the framework is a functional, efficient, and pragmatic approach for gathering and synthesizing scientific knowledge on the state of biodiversity in any marine or terrestrial ecosystem and has general applicability worldwide.
Energy Technology Data Exchange (ETDEWEB)
Gromov, E. V. [Theoretical Chemistry, Institute of Physical Chemistry, University of Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany); Laboratory of Quantum Chemistry, Computer Center, Irkutsk State University, K. Marks 1, 664003 Irkutsk (Russian Federation); Reddy, V. Sivaranjana; Köppel, H. [Theoretical Chemistry, Institute of Physical Chemistry, University of Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany); Gatti, F. [CTMM, Institut Charles Gerhardt, UMR 5253, CC 1501, Université Montpellier II, 34095 Montpellier, Cedex 05 (France)
2013-12-21
A new general framework for treating the dynamics on intersecting multidimensional potential energy surfaces is presented. It rests on a sub-division of the nuclear coordinates into different classes, one of primary importance with large-amplitude displacements during the process of interest and another one with smaller displacements, thus permitting a more approximate description. The latter are treated within the well-known linear + quadratic vibronic coupling scheme, where, however, the expansion “coefficients” are general functions of the “primary” coordinates. This may be augmented by an effective-mode approach for further degrees of freedom acting as an environment for the dynamics of the original modes. Following the general considerations, the approach is applied to the nonadiabatic photodynamics of furan and is shown to allow for an eight-dimensional quantum treatment, of higher dimension than was possible so far. The influence of the various degrees of freedom on the dynamics and lifetime of furan due to nonadiabatic ring-opening is discussed.
A general theoretical framework for understanding essential dynamics of Madden-Julian oscillation
Wang, Bin; Chen, Guosen
2016-11-01
Motivated by observed structure of Madden-Julian oscillation (MJO), a general theoretical model framework is advanced for understanding fundamental aspects of MJO dynamics. The model extends the Matsuno-Gill theory by incorporating (a) moisture feedback to precipitation, (b) a trio-interaction among equatorial waves, boundary layer (BL) dynamics, and precipitation, and (c) a simplified Betts-Miller (B-M) cumulus parameterization. The general model with B-M scheme yields a frictionally coupled dynamic moisture mode, which produces an equatorial planetary-scale, unstable system moving eastward slowly with coupled Kelvin-Rossby wave structure and BL moisture convergence leading major convection. The moisture feedback in B-M scheme reinforces the coupling between precipitation heating and Rossby waves and enhances the Rossby wave component in the MJO mode, thereby slowing down eastward propagation and resulting in a more realistic horizontal structure. It is, however, the BL frictional convergence feedback that couples equatorial Kelvin and Rossby waves with convective heating and selects a preferred eastward propagation. The eastward propagation speed in the model is inversely related to the relative intensity of the equatorial "Rossby" westerly versus "Kelvin" easterly associated with the MJO. The cumulus parameterization scheme may affect propagation speed through changing MJO horizontal structure. The SST or basic-state moist static energy has a fundamental control on MJO propagation speed and intensification/decay. Model sensitivity to BL and cumulus scheme parameters and ramifications of the model results to general circulation modeling are discussed.
Self-Evaluation of Decision-Making: A General Bayesian Framework for Metacognitive Computation
2017-01-01
People are often aware of their mistakes, and report levels of confidence in their choices that correlate with objective performance. These metacognitive assessments of decision quality are important for the guidance of behavior, particularly when external feedback is absent or sporadic. However, a computational framework that accounts for both confidence and error detection is lacking. In addition, accounts of dissociations between performance and metacognition have often relied on ad hoc assumptions, precluding a unified account of intact and impaired self-evaluation. Here we present a general Bayesian framework in which self-evaluation is cast as a “second-order” inference on a coupled but distinct decision system, computationally equivalent to inferring the performance of another actor. Second-order computation may ensue whenever there is a separation between internal states supporting decisions and confidence estimates over space and/or time. We contrast second-order computation against simpler first-order models in which the same internal state supports both decisions and confidence estimates. Through simulations we show that second-order computation provides a unified account of different types of self-evaluation often considered in separate literatures, such as confidence and error detection, and generates novel predictions about the contribution of one’s own actions to metacognitive judgments. In addition, the model provides insight into why subjects’ metacognition may sometimes be better or worse than task performance. We suggest that second-order computation may underpin self-evaluative judgments across a range of domains. PMID:28004960
A General Framework for Sequential and Adaptive Methods in Survival Studies
Luo, Xiaolong; Ying, Zhiliang
2011-01-01
Adaptive treatment allocation schemes based on interim responses have generated a great deal of recent interest in clinical trials and other follow-up studies. An important application of such schemes is in survival studies, where the response variable of interest is time to the occurrence of a certain event. Due to possible dependency structures inherited from the enrollment and allocation schemes, existing approaches to survival models, including those that handle staggered entry, cannot be applied directly. This paper develops a new general framework with its theoretical foundation for handling such adaptive designs. The new approach is based on marked point processes and differs from existing approaches in that it considers entry and calender times rather than survival and calender times. Large sample properties, which are essential for statistical inference, are established. Special attention is given to the Cox model and related score processes. Applications to adaptive and sequential designs are discus...
An Approach to Optical Network Design using General Heuristic Optimization Framework
Directory of Open Access Journals (Sweden)
Marko Lacković
2010-12-01
Full Text Available The article tackles the problem of optimization methods in optical network design process, based on optimal traffic routing with the goal to minimize the utilized network resources for given topology and traffic demands. An optimization framework Nyx has been developed with the focus on flexibility in solving optimization problems by implementing general heuristic search techniques. Nyx modular organization has been described, including coding types for solutions and genetic algorithm as the optimization method. Optimal routing has been implemented to demonstrate the use of Nyx in the optical network design process. Optimal routing procedure has been applied to Pan-European optical network with variations of routing procedures and the number of wavelengths. The analysis included no protection scenario, 1+1 protection and path restoration. The routing was performed using shortest path routing and optimal routing which minimizes the use of optical network resources, being network multiplexers, amplifiers and fibers.
MObIUS (Massive Object Integrated Universal Store): A Survey Toward a More General Framework
Energy Technology Data Exchange (ETDEWEB)
Sirp, J K; Brugger, S T
2004-06-07
General frameworks for distributed computing are slowly evolving out of Grid, Peer Architecture, and Web Services. The following results from a summer long survey into distributing computing practices have revealed three things. One, that Legion and Cactus-G have achieved the most in terms of providing an all-purpose application environment. Two, that extending a local programming environment to operate in a highly distributed fashion can be facilitated with toolkits like Globus. Three, that building a new system from the ground up could be realized, in part, by using some of the following components; an Object Oriented Database, Tapestry, JXTA, BOINC, Globus, component architecture technology, XML and related libraries, Condor-G, Proteus, and ParMETIS.
A general framework of persistence strategies for biological systems helps explain domains of life
Directory of Open Access Journals (Sweden)
Liudmila S Yafremava
2013-02-01
Full Text Available The nature and cause of the division of organisms in superkingdoms is not fully understood. Assuming that environment shapes physiology, here we construct a novel theoretical framework that helps identify general patterns of organism persistence. This framework is based on Jacob von Uexküll’s organism-centric view of the environment and James G. Miller’s view of organisms as matter-energy-information processing molecular machines. Three concepts describe an organism's environmental niche: scope, umwelt and gap. Scope denotes the entirety of environmental events and conditions to which the organism is exposed during its lifetime. Umwelt encompasses an organism's perception of these events. The gap is the organism's blind spot, the scope that is not covered by umwelt. These concepts bring organisms of different complexity to a common ecological denominator. Ecological and physiological data suggest organisms persist using three strategies: flexibility, robustness and economy. All organisms use umwelt information to flexibly adapt to environmental change. They implement robustness against environmental perturbations within the gap generally through redundancy and reliability of internal constituents. Both flexibility and robustness improve survival. However, they also incur metabolic matter-energy processing costs, which otherwise could have been used for growth and reproduction. Lineages evolve unique tradeoff solutions among strategies in the space of what we call a persistence triangle. Protein domain architecture and other evidence support the preferential use of flexibility and robustness properties. Archaea and Bacteria gravitate toward the triangle’s economy vertex, with Archaea biased toward robustness. Eukarya trade economy for survivability. Protista occupy a saddle manifold separating akaryotes from multicellular organisms. Plants and the more flexible Fungi share an economic stratum, and Metazoa are locked in a positive feedback
A General Framework of Persistence Strategies for Biological Systems Helps Explain Domains of Life
Yafremava, Liudmila S.; Wielgos, Monica; Thomas, Suravi; Nasir, Arshan; Wang, Minglei; Mittenthal, Jay E.; Caetano-Anollés, Gustavo
2012-01-01
The nature and cause of the division of organisms in superkingdoms is not fully understood. Assuming that environment shapes physiology, here we construct a novel theoretical framework that helps identify general patterns of organism persistence. This framework is based on Jacob von Uexküll’s organism-centric view of the environment and James G. Miller’s view of organisms as matter-energy-information processing molecular machines. Three concepts describe an organism’s environmental niche: scope, umwelt, and gap. Scope denotes the entirety of environmental events and conditions to which the organism is exposed during its lifetime. Umwelt encompasses an organism’s perception of these events. The gap is the organism’s blind spot, the scope that is not covered by umwelt. These concepts bring organisms of different complexity to a common ecological denominator. Ecological and physiological data suggest organisms persist using three strategies: flexibility, robustness, and economy. All organisms use umwelt information to flexibly adapt to environmental change. They implement robustness against environmental perturbations within the gap generally through redundancy and reliability of internal constituents. Both flexibility and robustness improve survival. However, they also incur metabolic matter-energy processing costs, which otherwise could have been used for growth and reproduction. Lineages evolve unique tradeoff solutions among strategies in the space of what we call “a persistence triangle.” Protein domain architecture and other evidence support the preferential use of flexibility and robustness properties. Archaea and Bacteria gravitate toward the triangle’s economy vertex, with Archaea biased toward robustness. Eukarya trade economy for survivability. Protista occupy a saddle manifold separating akaryotes from multicellular organisms. Plants and the more flexible Fungi share an economic stratum, and Metazoa are locked in a positive feedback loop
Hodnik Cadež, Tatjana; Manfreda Kolar, Vida
2015-01-01
A cognitive schema is a mechanism which allows an individual to organize her/his experiences in such a way that a new similar experience can easily be recognised and dealt with successfully. Well-structured schemas provide for the knowledge base for subsequent mathematical activities. A new experience can be assimilated into a previously existing…
Working memory deficit in children with mathematical difficulties: a general or specific deficit?
Andersson, Ulf; Lyxell, Björn
2007-03-01
This study examined whether children with mathematical difficulties (MDs) or comorbid mathematical and reading difficulties have a working memory deficit and whether the hypothesized working memory deficit includes the whole working memory system or only specific components. In the study, 31 10-year-olds with MDs and 37 10-year-olds with both mathematical and reading difficulties were compared with 47 age-matched and 50 younger controls (9-year-olds) on a number of working memory tasks. Compared with the age-matched controls, both groups of children with MDs performed worse on tasks tapping the central executive (e.g., visual matrix span) and the phonological loop (e.g., word span). More important, the MD group performed worse than the younger controls on the counting span task, whereas the group with comorbid mathematical and reading difficulties performed worse on the counting span task and the visual matrix span task. These findings provide support for the assumption that children with MDs have a working memory deficit. More specifically, children with MDs have a central executive deficit connected to concurrent processing and storage of numerical and visual information.
Request for All - A Generalized Request Framework for PhEDEx
Energy Technology Data Exchange (ETDEWEB)
Huang, C.-H. [Fermilab; Wildish, T. [Princeton U.; Ratnikova, N. [Fermilab; Sanchez-Hernandez, A. [CINVESTAV, IPN; Zhang, X. [Beijing, Inst. High Energy Phys.; Magini, N. [CERN
2014-01-01
PhEDEx has been serving CMS community since 2004 as the data broker. Every PhEDEx operation is initiated by a request, e.g. request to move or to delete data, and so on. A request has it own life cycle, including creation, approval, notification, and book keeping and the details depend on its type. Currently, only two kinds of requests, transfer and deletion, are fully integrated in PhEDEx. They are tailored specifically to the operations' workflows. To be able to serve a new type of request it generally means a fair amount of development work. After several many years of operation, we have gathered enough experience to rethink the request handling in PhEDEx. Generalized Request Project is set to abstract such experience and design a request system which is not tied into current workflow yet it is general enough to accommodate current and future requests. The challenges are dealing with different stages in a request's life cycle, complexity of approval process and complexity of the ability and authority associated with each role in the context of the request. We start with a high level abstraction driven by a deterministic finite automata, followed by a formal description and handling of approval process, followed by a set of tools that make such system friendly to the users. Since we have a formal way to describe the life of a request and a mechanism to systematically handle it, to serve a new kind of request is merely a configuration issue, adding the description of the new request rather than development effort. In this paper, we share the design and implementation of a generalized request framework and the experience of taking an existing serving system through a re-design and re-deployment.
Skrzypek, Josef; Mesrobian, Edmond; Gungner, David J.
1989-03-01
The development of autonomous land vehicles (ALV) capable of operating in an unconstrained environment has proven to be a formidable research effort. The unpredictability of events in such an environment calls for the design of a robust perceptual system, an impossible task requiring the programming of a system bases on the expectation of future, unconstrained events. Hence, the need for a "general purpose" machine vision system that is capable of perceiving and understanding images in an unconstrained environment in real-time. The research undertaken at the UCLA Machine Perception Laboratory addresses this need by focusing on two specific issues: 1) the long term goals for machine vision research as a joint effort between the neurosciences and computer science; and 2) a framework for evaluating progress in machine vision. In the past, vision research has been carried out independently within different fields including neurosciences, psychology, computer science, and electrical engineering. Our interdisciplinary approach to vision research is based on the rigorous combination of computational neuroscience, as derived from neurophysiology and neuropsychology, with computer science and electrical engineering. The primary motivation behind our approach is that the human visual system is the only existing example of a "general purpose" vision system and using a neurally based computing substrate, it can complete all necessary visual tasks in real-time.
Corvo, Arthur Francis
Given the reality that active and competitive participation in the 21 st century requires American students to deepen their scientific and mathematical knowledge base, the National Research Council (NRC) proposed a new conceptual framework for K--12 science education. The framework consists of an integration of what the NRC report refers to as the three dimensions: scientific and engineering practices, crosscutting concepts, and core ideas in four disciplinary areas (physical, life and earth/spaces sciences, and engineering/technology). The Next Generation Science Standards (NGSS ), which are derived from this new framework, were released in April 2013 and have implications on teacher learning and development in Science, Technology, Engineering, and Mathematics (STEM). Given the NGSS's recent introduction, there is little research on how teachers can prepare for its release. To meet this research need, I implemented a self-study aimed at examining my teaching practices and classroom outcomes through the lens of the NRC's conceptual framework and the NGSS. The self-study employed design-based research (DBR) methods to investigate what happened in my secondary classroom when I designed, enacted, and reflected on units of study for my science, engineering, and mathematics classes. I utilized various best practices including Learning for Use (LfU) and Understanding by Design (UbD) models for instructional design, talk moves as a tool for promoting discourse, and modeling instruction for these designed units of study. The DBR strategy was chosen to promote reflective cycles, which are consistent with and in support of the self-study framework. A multiple case, mixed-methods approach was used for data collection and analysis. The findings in the study are reported by study phase in terms of unit planning, unit enactment, and unit reflection. The findings have implications for science teaching, teacher professional development, and teacher education.
2010-01-01
Background Fractal geometry is employ to characterize the irregular objects and had been used in experimental and clinic applications. Starting from a previous work, here we made a theoretical research based on a geometric generalization of the experimental results, to develop a theoretical generalization of the stenotic and restenotic process, based on fractal geometry and Intrinsic Mathematical Harmony. Methods Starting from all the possibilities of space occupation in box-counting space, all arterial prototypes differentiating normality and disease were obtained with a computational simulation. Measures from 2 normal and 3 re-stenosed arteries were used as spatial limits of the generalization. Results A new methodology in animal experimentation was developed, based on fractal geometric generalization. With this methodology, it was founded that the occupation space possibilities in the stenotic process are finite and that 69,249 arterial prototypes are obtained as a total. Conclusions The Intrinsic Mathematical Harmony reveals a supra-molecular geometric self-organization, where the finite and discrete fractal dimensions of arterial layers evaluate objectively the arterial stenosis and restenosis process. PMID:20846449
Dostal, T.; Krasa, J.
2009-04-01
quality management. The above mentioned calculations and mathematical simulations are still assumed mostly being a domain of science and it is not accepted that many analysis and models were already finished to the level of practical routine applicability. Another important problem is missing relation and cooperation between environmental field (where for instance Water Framework Directive is also assumed to be included) and economical and social fields. The regulative and limits are set up in the area of agriculture on one hand, to reach economic goals in food production, but on the other hand, side effects of those measures to water quality protection are not assumed and vice-versa, watershed management measures are mostly not assessed from point of view of the effects on a desired economic field. Already (Van Rompaey et al., 2000) examined the effect of conversion of arable land into peace (conversion mostly to grassland) in agreement with European agricultural policy of food overproduction prevention, on sediment transport into water reservoirs. Based on mathematical simulations and survey between farmers he approved that unimportant increasing of proportion of converted land in certain regions can significantly influence sediment transport and water quality in given catchment. Proposed presentation tends to invoke support of international and interdepartmental cooperation in given fields and to present various possibilities of application of mathematical modeling and GIS assisted analyses on the level of practical and routine applicability for watershed management in various scales. Acknowledgement: This paper has been worked out based on the results reached with support of the project "MSMT CR VZ CEZ MSM 6840770002 - Revitalization of water systems of the landscape and urban sites, significantly affected by anthropogenic changes". References • Dostal T., Krasa J., Vaska J., Vrana K., 2001. The map of soil erosion risk and sediment transport in the Czech Republic
Eremeyev, Victor A.; Lebedev, Leonid P.
2016-03-01
Mathematical questions pertaining to linear problems of equilibrium dynamics and vibrations of elastic bodies with surface stresses are studied. We extend our earlier results on existence of weak solutions within the Gurtin-Murdoch model to the Steigmann-Ogden model of surface elasticity using techniques from the theory of Sobolev's spaces and methods of functional analysis. The Steigmann-Ogden model accounts for the bending stiffness of the surface film; it is a generalization of the Gurtin-Murdoch model. Weak setups of the problems, based on variational principles formulated, are employed. Some uniqueness-existence theorems for weak solutions of static and dynamic problems are proved in energy spaces via functional analytic methods. On the boundary surface, solutions to the problems under consideration are smoother than those for the corresponding problems of classical linear elasticity and those described by the Gurtin-Murdoch model. The weak setups of eigenvalue problems for elastic bodies with surface stresses are based on the Rayleigh and Courant variational principles. For the problems based on the Steigmann-Ogden model, certain spectral properties are established. In particular, bounds are placed on the eigenfrequencies of an elastic body with surface stresses; these demonstrate the increase in the body rigidity and the eigenfrequencies compared with the situation where the surface stresses are neglected.
Blum, Alexander; Lalli, Roberto; Renn, M Jürgen
2015-09-01
The history of the theory of general relativity presents unique features. After its discovery, the theory was immediately confirmed and rapidly changed established notions of space and time. The further implications of general relativity, however, remained largely unexplored until the mid 1950s, when it came into focus as a physical theory and gradually returned to the mainstream of physics. This essay presents a historiographical framework for assessing the history of general relativity by taking into account in an integrated narrative intellectual developments, epistemological problems, and technological advances; the characteristics of post-World War II and Cold War science; and newly emerging institutional settings. It argues that such a framework can help us understand this renaissance of general relativity as a result of two main factors: the recognition of the untapped potential of general relativity and an explicit effort at community building, which allowed this formerly disparate and dispersed field to benefit from the postwar changes in the scientific landscape.
Directory of Open Access Journals (Sweden)
Vitor Geraldi Haase
2014-02-01
Full Text Available Mathematics learning difficulties are a highly comorbid and heterogeneous set of disorders linked to several dissociable mechanisms and endophenotypes. Two of these endophenotypes consist of primary deficits in number sense and verbal numerical representations. However, currently acknowledged endophenotypes are underspecified regarding the role of automatic vs. controlled information processing, and their description should be complemented. Two children with specific deficits in number sense and verbal numerical representations and normal or above-normal intelligence and preserved visuospatial cognition illustrate this point. Child H.V. exhibited deficits in number sense and fact retrieval. Child G.A. presented severe deficits in orally presented problems and transcoding tasks. A partial confirmation of the two endophenotypes that relate to the number sense and verbal processing was obtained, but a much more clear differentiation between the deficits presented by H.V. and G.A. can be reached by looking at differential impairments in modes of processing. H.V. is notably competent in the use of controlled processing but has problems with more automatic processes, such as nonsymbolic magnitude processing, speeded counting and fact retrieval. In contrast, G.A. can retrieve facts and process nonsymbolic magnitudes but exhibits severe impairment in recruiting executive functions and the concentration that is necessary to accomplish transcoding tasks and word problem solving. These results indicate that typical endophenotypes might be insufficient to describe accurately the deficits that are observed in children with mathematics learning abilities. However, by incorporating domain-specificity and modes of processing into the assessment of the endophenotypes, individual deficit profiles can be much more accurately described. This process calls for further specification of the endophenotypes in mathematics learning difficulties.
Haase, Vitor G; Júlio-Costa, Annelise; Lopes-Silva, Júlia B; Starling-Alves, Isabella; Antunes, Andressa M; Pinheiro-Chagas, Pedro; Wood, Guilherme
2014-01-01
Mathematics learning difficulties are a highly comorbid and heterogeneous set of disorders linked to several dissociable mechanisms and endophenotypes. Two of these endophenotypes consist of primary deficits in number sense and verbal numerical representations. However, currently acknowledged endophenotypes are underspecified regarding the role of automatic vs. controlled information processing, and their description should be complemented. Two children with specific deficits in number sense and verbal numerical representations and normal or above-normal intelligence and preserved visuospatial cognition illustrate this point. Child H.V. exhibited deficits in number sense and fact retrieval. Child G.A. presented severe deficits in orally presented problems and transcoding tasks. A partial confirmation of the two endophenotypes that relate to the number sense and verbal processing was obtained, but a much more clear differentiation between the deficits presented by H.V. and G.A. can be reached by looking at differential impairments in modes of processing. H.V. is notably competent in the use of controlled processing but has problems with more automatic processes, such as nonsymbolic magnitude processing, speeded counting and fact retrieval. In contrast, G.A. can retrieve facts and process nonsymbolic magnitudes but exhibits severe impairment in recruiting executive functions and the concentration that is necessary to accomplish transcoding tasks and word problem solving. These results indicate that typical endophenotypes might be insufficient to describe accurately the deficits that are observed in children with mathematics learning abilities. However, by incorporating domain-specificity and modes of processing into the assessment of the endophenotypes, individual deficit profiles can be much more accurately described. This process calls for further specification of the endophenotypes in mathematics learning difficulties.
DEFF Research Database (Denmark)
Blomhøj, Morten
2004-01-01
Developing competences for setting up, analysing and criticising mathematical models are normally seen as relevant only from and above upper secondary level. The general belief among teachers is that modelling activities presuppose conceptual understanding of the mathematics involved. Mathematical...... modelling, however, can be seen as a practice of teaching that place the relation between real life and mathematics into the centre of teaching and learning mathematics, and this is relevant at all levels. Modelling activities may motivate the learning process and help the learner to establish cognitive...... roots for the construction of important mathematical concepts. In addition competences for setting up, analysing and criticising modelling processes and the possible use of models is a formative aim in this own right for mathematics teaching in general education. The paper presents a theoretical...
The generalized mathematical model of the failure of the cutting tool
Pasko, N. I.; Antsev, A. V.; Antseva, N. V.; Fyodorov, V. P.
2017-02-01
We offer a mathematical model which takes into account the following factors: the spread of the cutting properties of the tool, parameters spread of gear blanks and consideration of the factor of a possible fracture of the cutting wedge tool. The reliability function, taking into account the above-mentioned factors, has five parameters for which assessment we propose a method according to our experience. A numerical illustration of the method is shown in the article. We suggest using the model in the optimization mode of the cutting tool preventive measures.
Ward Jones, Sarah E; Chevallier, François G; Paddon, Christopher A; Compton, Richard G
2007-06-01
Theory is presented to describe the voltammetric signals associated with the stripping phase of stripping voltammetry at solid electrodes. Three mathematical models are considered, and the importance of the hemispherical diffusion associated with electrochemical dissolution of particles in the micrometer range is investigated. Model A considers a "monolayer" system where the coverage at a specific point cannot exceed a maximum value. Model B considers a thin layer of metal or metal oxide, but in contrast to model A, the maximum surface coverage is not restricted. Model C represents the stripping of a "thick layer" where the deposition is also unrestricted.
通用本体学习框架研究%General ontology learning framework
Institute of Scientific and Technical Information of China (English)
刘柏嵩; 高济
2006-01-01
In order to reduce the costs of the ontology construction,a general ontology learning framework (GOLF) is developed.The key technologies of the GOLF including domain concepts extraction and semantic relationships between concepts and taxonomy automatic construction are proposed.At the same time ontology evaluation methods are also discussed.The experimental results show that this method produces better performance and it is applicable across different domains.By integrating several machine learning algorithms,this method suffers less ambiguity and can identify domain concepts and relations more accurately.By using generalized corpus WordNet and HowNet,this method is applicable across different domains.In addition,by obtaining source documents from the web on demand, the GOLF can produce up-to-date ontologies.%提出了一种通用本体学习框架GOLF,通过对网络上各专业领域web文档集进行挖掘来实现本体自动构建,讨论了本体学习中本体概念的抽取、概念之间语义关系的抽取和分类体系的自动构建等关键技术,通过实验对算法进行了测试,并对本体评价方法进行了探讨.由于集成了多种机器学习算法,该方法在概念抽取和语义关系学习方面具有更高的准确性.采用通用本体WordNet和HowNet作为语料库,它可适用于不同的专业领域.同时,通过按需获取web文档,该方法能实时生成本体.
Lappa, Marcello
2016-05-01
The relevance of non-equilibrium phenomena, nonlinear behavior, gravitational effects and fluid compressibility in a wide range of problems related to high-temperature gas-dynamics, especially in thermal, mechanical and nuclear engineering, calls for a concerted approach using the tools of the kinetic theory of gases, statistical physics, quantum mechanics, thermodynamics and mathematical modeling in synergy with advanced numerical strategies for the solution of the Navier-Stokes equations. The reason behind such a need is that in many instances of relevance in this field one witnesses a departure from canonical models and the resulting inadequacy of standard CFD approaches, especially those traditionally used to deal with thermal (buoyancy) convection problems. Starting from microscopic considerations and typical concepts of molecular dynamics, passing through the Boltzmann equation and its known solutions, we show how it is possible to remove past assumptions and elaborate an algorithm capable of targeting the broadest range of applications. Moving beyond the Boussinesq approximation, the Sutherland law and the principle of energy equipartition, the resulting method allows most of the fluid properties (density, viscosity, thermal conductivity, heat capacity and diffusivity, etc.) to be derived in a rational and natural way while keeping empirical contamination to the minimum. Special attention is deserved as well to the well-known pressure issue. With the application of the socalled multiple pressure variables concept and a projection-like numerical approach, difficulties with such a term in the momentum equation are circumvented by allowing the hydrodynamic pressure to decouple from its thermodynamic counterpart. The final result is a flexible and modular framework that on the one hand is able to account for all the molecule (translational, rotational and vibrational) degrees of freedom and their effective excitation, and on the other hand can guarantee adequate
Satisfaction Equilibrium: A General Framework for QoS Provisioning in Self-Configuring Networks
Perlaza, Samir M; Lasaulce, Samson; Debbah, Merouane
2010-01-01
This paper is concerned with the concept of equilibrium and quality of service (QoS) provisioning in self-configuring wireless networks with non-cooperative radio devices (RD). In contrast with the Nash equilibrium (NE), where RDs are interested in selfishly maximizing its QoS, we present a concept of equilibrium, named satisfaction equilibrium (SE), where RDs are interested only in guaranteing a minimum QoS. We provide the conditions for the existence and the uniqueness of the SE. Later, in order to provide an equilibrium selection framework for the SE, we introduce the concept of effort or cost of satisfaction, for instance, in terms of transmit power levels, constellation sizes, etc. Using the idea of effort, the set of efficient SE (ESE) is defined. At the ESE, transmitters satisfy their minimum QoS incurring in the lowest effort. We prove that contrary to the (generalized) NE, at least one ESE always exists whenever the network is able to simultaneously support the individual QoS requests. Finally, we pr...
Directory of Open Access Journals (Sweden)
Antonio Maria Scarfone
2015-05-01
Full Text Available We explore two possible generalizations of the Euler formula for the complex \\(\\kappa\\-exponential, which give two different sets of \\(\\kappa\\-deformed cyclic functions endowed with different analytical properties. In a case, the \\(\\kappa\\-sine and \\(\\kappa\\-cosine functions take real values on \\(\\Re\\ and are characterized by an asymptotic log-periodic behavior. In the other case, the \\(\\kappa\\-cyclic functions take real values only in the region \\(|x|\\leq1/|\\kappa|\\, while, for \\(|x|>1/|\\kappa|\\, they assume purely imaginary values with an increasing modulus. However, the main mathematical properties of the standard cyclic functions, opportunely reformulated in the formalism of the \\(\\kappa\\-mathematics, are fulfilled by the two sets of the \\(\\kappa\\-trigonometric functions. In both cases, we study the orthogonality and the completeness relations and introduce their respective generalized Fourier series for square integrable functions.
Energy Technology Data Exchange (ETDEWEB)
Ruehrnschopf, Ernst-Peter; Klingenbeck, Klaus [Siemens AG, Healthcare Sector, Imaging and Therapy Division, Forchheim (Germany)
2011-07-15
Since scattered radiation in cone-beam volume CT implies severe degradation of CT images by quantification errors, artifacts, and noise increase, scatter suppression is one of the main issues related to image quality in CBCT imaging. The aim of this review is to structurize the variety of scatter suppression methods, to analyze the common structure, and to develop a general framework for scatter correction procedures. In general, scatter suppression combines hardware techniques of scatter rejection and software methods of scatter correction. The authors emphasize that scatter correction procedures consist of the main components scatter estimation (by measurement or mathematical modeling) and scatter compensation (deterministic or statistical methods). The framework comprises most scatter correction approaches and its validity also goes beyond transmission CT. Before the advent of cone-beam CT, a lot of papers on scatter correction approaches in x-ray radiography, mammography, emission tomography, and in Megavolt CT had been published. The opportunity to avail from research in those other fields of medical imaging has not yet been sufficiently exploited. Therefore additional references are included when ever it seems pertinent. Scatter estimation and scatter compensation are typically intertwined in iterative procedures. It makes sense to recognize iterative approaches in the light of the concept of self-consistency. The importance of incorporating scatter compensation approaches into a statistical framework for noise minimization has to be underscored. Signal and noise propagation analysis is presented. A main result is the preservation of differential-signal-to-noise-ratio (dSNR) in CT projection data by ideal scatter correction. The objective of scatter compensation methods is the restoration of quantitative accuracy and a balance between low-contrast restoration and noise reduction. In a synopsis section, the different deterministic and statistical methods are
Directory of Open Access Journals (Sweden)
Taniana Rodríguez
2014-01-01
Full Text Available En este trabajo se propone una arquitectura de Aprendizaje Onto lógico, que es uno de los componentes claves del Marco Ontológi co Dinámico Semántico (MODS para la Web Semántica. Esta arquitect ura general soporta la adquisición automática de conocimiento léxico y semántico. En particular, permite la adquisición de co nocimiento sobre términos (palabras, conceptos (taxonómicos, n o taxonómicos, relaciones entre ellos, reglas de producción o ax iomas. La arquitectura establece donde cada conocimiento adquir ido debe ser incorporado en las estructuras del MODS, ya sea en su ontol ogía interpretativa, ontología lingüística, o lexicón. Además, el trabajo presenta un ejemplo de uso de la arquitectura para el caso del aprendizaje semántico.
ROSE: The Design of a General Tool for the Independent Optimization of Object-Oriented Frameworks
Energy Technology Data Exchange (ETDEWEB)
Davis, K.; Philip, B.; Quinlan, D.
1999-05-18
ROSE represents a programmable preprocessor for the highly aggressive optimization of C++ object-oriented frameworks. A fundamental feature of ROSE is that it preserves the semantics, the implicit meaning, of the object-oriented framework's abstractions throughout the optimization process, permitting the framework's abstractions to be recognized and optimizations to capitalize upon the added value of the framework's true meaning. In contrast, a C++ compiler only sees the semantics of the C++ language and thus is severely limited in what optimizations it can introduce. The use of the semantics of the framework's abstractions avoids program analysis that would be incapable of recapturing the framework's full semantics from those of the C++ language implementation of the application or framework. Just as no level of program analysis within the C++ compiler would not be expected to recognize the use of adaptive mesh refinement and introduce optimizations based upon such information. Since ROSE is programmable, additional specialized program analysis is possible which then compliments the semantics of the framework's abstractions. Enabling an optimization mechanism to use the high level semantics of the framework's abstractions together with a programmable level of program analysis (e.g. dependence analysis), at the level of the framework's abstractions, allows for the design of high performance object-oriented frameworks with uniquely tailored sophisticated optimizations far beyond the limits of contemporary serial F0RTRAN 77, C or C++ language compiler technology. In short, faster, more highly aggressive optimizations are possible. The resulting optimizations are literally driven by the framework's definition of its abstractions. Since the abstractions within a framework are of third party design the optimizations are similarly of third party design, specifically independent of the compiler and the applications that use the
A Study on TIMSS2011 Mathematics Assessment Framework and Function%TIMSS2011数学教育评价框架及运行研究
Institute of Scientific and Technical Information of China (English)
赵慧
2015-01-01
The TIMSS2011 mathematics assessment framework, test and result are studied in this paper. In approach to TIMSS questionnaire comparison, containing home resource, school environments, teacher level and class instruction, the key factors are analyzed on the student mathematics achievement. Based on TIMSS2011 mathematics assessment results, the author proposes several suggestions to improve our school education and mathematics assessment.%本专题报告通过研究TIMSS2011数学评价框架及其实测试题构成，比较历次TIMSS测试框架的变化以及测试结果的变化，对照TIMSS问卷调查（家庭环境、学校资源和风气、教师配备、课堂教学），深入分析影响学生数学学业成就的关键因素。借鉴TIMSS数学评价的研究成果，对探讨改进我国中小学数学教育评价提出思考和建议。
Directory of Open Access Journals (Sweden)
Stefan Hollands
2009-09-01
Full Text Available In this paper, we propose a new framework for quantum field theory in terms of consistency conditions. The consistency conditions that we consider are ''associativity'' or ''factorization'' conditions on the operator product expansion (OPE of the theory, and are proposed to be the defining property of any quantum field theory. Our framework is presented in the Euclidean setting, and is applicable in principle to any quantum field theory, including non-conformal ones. In our framework, we obtain a characterization of perturbations of a given quantum field theory in terms of a certain cohomology ring of Hochschild-type. We illustrate our framework by the free field, but our constructions are general and apply also to interacting quantum field theories. For such theories, we propose a new scheme to construct the OPE which is based on the use of non-linear quantized field equations.
Energy Technology Data Exchange (ETDEWEB)
Santiago, J. L.; Martin, N.; Correa, C.
2013-07-01
This article summarizes the legal framework defining the strategies, the main activities and the basic responsibilities and roles of the various agents involved in the decommissioning of nuclear facilities in Spain. It also describes briefly the most relevant projects and activities already developed and/or ongoing nowadays, which have positioned Spain within the small group of countries having an integrated and proved experience and know how in this particular field. (Author)
Liu, Yingyi
2017-09-08
Prior studies on fraction magnitude understanding focused mainly on students with relatively sufficient formal instruction on fractions whose fraction magnitude understanding is relatively mature. This study fills a research gap by investigating fraction magnitude understanding in the early stages of fraction instruction. It extends previous findings to children with limited and primary formal fraction instruction. Thirty-five fourth graders with limited fraction instruction and forty fourth graders with primary fraction instruction were recruited from a Chinese primary school. Children's fraction magnitude understanding was assessed with a fraction number line estimation task. Approximate number system (ANS) acuity was assessed with a dot discrimination task. Whole number knowledge was assessed with a whole number line estimation task. General reading and mathematics achievements were collected concurrently and 1 year later. In children with limited fraction instruction, fraction representation was linear and fraction magnitude understanding was concurrently related to both ANS and whole number knowledge. In children with primary fraction instruction, fraction magnitude understanding appeared to (marginally) significantly predict general mathematics achievement 1 year later. Fraction magnitude understanding emerged early during formal instruction of fractions. ANS and whole number knowledge were related to fraction magnitude understanding when children first began to learn about fractions in school. The predictive value of fraction magnitude understanding is likely constrained by its sophistication level. © 2017 The British Psychological Society.
Aiguier, Marc; Atif, Jamal; Bloch, Isabelle; Hudelot, Céline
2015-01-01
Belief revision of knowledge bases represented by a set of sentences in a given logic has been extensively studied but for specific logics, mainly propositional, and also recently Horn and description logics. Here, we propose to generalize this operation from a model-theoretic point of view, by defining revision in an abstract model theory known under the name of satisfaction systems. In this framework, we generalize to any satisfaction systems the characterization of the well known AGM postu...
Mathematical grammar of biology
Yamagishi, Michel Eduardo Beleza
2017-01-01
This seminal, multidisciplinary book shows how mathematics can be used to study the first principles of DNA. Most importantly, it enriches the so-called “Chargaff’s grammar of biology” by providing the conceptual theoretical framework necessary to generalize Chargaff’s rules. Starting with a simple example of DNA mathematical modeling where human nucleotide frequencies are associated to the Fibonacci sequence and the Golden Ratio through an optimization problem, its breakthrough is showing that the reverse, complement and reverse-complement operators defined over oligonucleotides induce a natural set partition of DNA words of fixed-size. These equivalence classes, when organized into a matrix form, reveal hidden patterns within the DNA sequence of every living organism. Intended for undergraduate and graduate students both in mathematics and in life sciences, it is also a valuable resource for researchers interested in studying invariant genomic properties.
Dong, Nianbo; Spybrook, Jessaca; Kelcey, Ben
2016-01-01
The purpose of this study is to propose a general framework for power analyses to detect the moderator effects in two- and three-level cluster randomized trials (CRTs). The study specifically aims to: (1) develop the statistical formulations for calculating statistical power, minimum detectable effect size (MDES) and its confidence interval to…
Hart, Sara A; Petrill, Stephen A; Thompson, Lee A; Plomin, Robert
2009-05-01
The goal of this first major report from the Western Reserve Reading Project Math component is to explore the etiology of the relationship among tester-administered measures of mathematics ability, reading ability, and general cognitive ability. Data are available on 314 pairs of monozygotic and same-sex dizygotic twins analyzed across 5 waves of assessment. Univariate analyses provide a range of estimates of genetic (h(2) = .00 -.63) and shared (c(2) = .15-.52) environmental influences across math calculation, fluency, and problem solving measures. Multivariate analyses indicate genetic overlap between math problem solving with general cognitive ability and reading decoding, whereas math fluency shares significant genetic overlap with reading fluency and general cognitive ability. Further, math fluency has unique genetic influences. In general, math ability has shared environmental overlap with general cognitive ability and decoding. These results indicate that aspects of math that include problem solving have different genetic and environmental influences than math calculation. Moreover, math fluency, a timed measure of calculation, is the only measured math ability with unique genetic influences.
Mathematics Lectures as Narratives: Insights from Network Graph Methodology
Weinberg, Aaron; Wiesner, Emilie; Fukawa-Connelly, Tim
2016-01-01
Although lecture is the traditional method of university mathematics instruction, there has been little empirical research that describes the general structure of lectures. In this paper, we adapt ideas from narrative analysis and apply them to an upper-level mathematics lecture. We develop a framework that enables us to conceptualize the lecture…
Nemoto, Mitsutaka; Hayashi, Naoto; Hanaoka, Shouhei; Nomura, Yukihiro; Miki, Soichiro; Yoshikawa, Takeharu
2017-04-12
We propose a generalized framework for developing computer-aided detection (CADe) systems whose characteristics depend only on those of the training dataset. The purpose of this study is to show the feasibility of the framework. Two different CADe systems were experimentally developed by a prototype of the framework, but with different training datasets. The CADe systems include four components; preprocessing, candidate area extraction, candidate detection, and candidate classification. Four pretrained algorithms with dedicated optimization/setting methods corresponding to the respective components were prepared in advance. The pretrained algorithms were sequentially trained in the order of processing of the components. In this study, two different datasets, brain MRA with cerebral aneurysms and chest CT with lung nodules, were collected to develop two different types of CADe systems in the framework. The performances of the developed CADe systems were evaluated by threefold cross-validation. The CADe systems for detecting cerebral aneurysms in brain MRAs and for detecting lung nodules in chest CTs were successfully developed using the respective datasets. The framework was shown to be feasible by the successful development of the two different types of CADe systems. The feasibility of this framework shows promise for a new paradigm in the development of CADe systems: development of CADe systems without any lesion specific algorithm designing.
Mathematical Story: A Metaphor for Mathematics Curriculum
Dietiker, Leslie
2015-01-01
This paper proposes a theoretical framework for interpreting the content found in mathematics curriculum in order to offer teachers and other mathematics educators comprehensive conceptual tools with which to make curricular decisions. More specifically, it describes a metaphor of "mathematics curriculum as story" and defines and…
Directory of Open Access Journals (Sweden)
Hasibun Naher
2014-10-01
Full Text Available In this article, new extension of the generalized and improved (G′/G-expansion method is proposed for constructing more general and a rich class of new exact traveling wave solutions of nonlinear evolution equations. To demonstrate the novelty and motivation of the proposed method, we implement it to the Korteweg-de Vries (KdV equation. The new method is oriented toward the ease of utilize and capability of computer algebraic system and provides a more systematic, convenient handling of the solution process of nonlinear equations. Further, obtained solutions disclose a wider range of applicability for handling a large variety of nonlinear partial differential equations.
How Can Students Generalize the Chain Rule? The Roles of Abduction in Mathematical Modeling
Park, Jin Hyeong; Lee, Kyeong-Hwa
2016-01-01
The purpose of this study is to design a modeling task to facilitate students' inquiries into the chain rule in calculus and to analyze the results after implementation of the task. In this study, we take a modeling approach to the teaching and learning of the chain rule by facilitating the generalization of students' models and modeling…
A generalization of the MDS method by mixed integer linear and nonlinear mathematical models
Directory of Open Access Journals (Sweden)
Sadegh Niroomand
2014-09-01
Full Text Available The Multi-Dimensional Scaling (MDS method is used in statistics to detect hidden interrelations among multi-dimensional data and it has a wide range of applications. The method’s input is a matrix that describes the similarity/dissimilarity among objects of unknown dimension. The objects are generally reconstructed as points of a lower dimensional space to reveal the geometric configuration of the objects. The original MDS method uses Euclidean distance, for measuring both the distance of the reconstructed points and the bias of the reconstructed distances from the original similarity values. In this paper, these distances are distinguished, and distances other than Euclidean are also used, generalizing the MDS method. Two different distances may be used for the two different purposes. Therefore the instances of the generalized MDS model are denoted as model, where the first distance is the type of distance of the reconstructed points and the second one measures the bias of the reconstructed distances and the similarity values. In the case of and distances mixed-integer programming models are provided. The computational experiences show that the generalized model can catch the key properties of the original configuration, if any exist. Keywords: Multivariate Analysis; Multi-Dimensional Scaling; Optimization; Mixed Integer Linear Programming; Statistics.
Interactions of Field Independence and General Reasoning with Inductive Instruction in Mathematics.
McLeod, Douglas B.; Briggs, John T.
1980-01-01
The interaction of two aptitude variables, field independence and general reasoning, with treatments that differed in sequence of instruction, was investigated using either an inductive or deductive appraoch to the learning of properties of equivalence relations. Significant interactions were found. (Author/MK)
Shakhawath Hossain, Md; Bergstrom, D J; Chen, X B
2015-12-01
The in vitro chondrocyte cell culture for cartilage tissue regeneration in a perfusion bioreactor is a complex process. Mathematical modeling and computational simulation can provide important insights into the culture process, which would be helpful for selecting culture conditions to improve the quality of the developed tissue constructs. However, simulation of the cell culture process is a challenging task due to the complicated interaction between the cells and local fluid flow and nutrient transport inside the complex porous scaffolds. In this study, a mathematical model and computational framework has been developed to simulate the three-dimensional (3D) cell growth in a porous scaffold placed inside a bi-directional flow perfusion bioreactor. The model was developed by taking into account the two-way coupling between the cell growth and local flow field and associated glucose concentration, and then used to perform a resolved-scale simulation based on the lattice Boltzmann method (LBM). The simulation predicts the local shear stress, glucose concentration, and 3D cell growth inside the porous scaffold for a period of 30 days of cell culture. The predicted cell growth rate was in good overall agreement with the experimental results available in the literature. This study demonstrates that the bi-directional flow perfusion culture system can enhance the homogeneity of the cell growth inside the scaffold. The model and computational framework developed is capable of providing significant insight into the culture process, thus providing a powerful tool for the design and optimization of the cell culture process.
Mathematical definition of general systems based on semiotics and set theory (part of statics)
Zou, D D
2009-01-01
According to the relation between objects and time, our category of general systems theory was divided into three parts: statics, kinematics, and dynamics. In this part, beginning with clarifying fundamental in epistemology and semiotics, we gave the connections of measurements, partitions and functions. And conforming to customs, we defined the terms of quantity and value by our understanding of functions. Then the concept of relation quantity was coined to describe the relationship like distance and force. Farther more, we discussed correspondences established between two quantities, and the definitions and theorems of complete set based on it. Finally, we present the structure which can afford the obligation of general system, and also the definitions of subsystem and isomorphism.
Kodaira, Kunihiko
1996-01-01
This is the translation from the Japanese textbook for the grade 11 course, "General Mathematics". It is part of the easier of the three elective courses in mathematics offered at this level and is taken by about 40% of students. The book covers basic notions of probability and statistics, vectors, exponential, logarithmic, and trigonometric functions, and an introduction to differentiation and integration.
Raible, Christoph C.; Baerenbold, Oliver; Gomez-Navarro, Juan Jose
2016-04-01
Over the past decades, different drought indices have been suggested in the literature. This study tackles the problem of how to characterize drought by defining a general framework and proposing a generalized family of drought indices that is flexible regarding the use of different water balance models. The sensitivity of various indices and its skill to represent drought conditions is evaluated using a regional model simulation in Europe spanning the last two millennia as test bed. The framework combines an exponentially damped memory with a normalization method based on quantile mapping. Both approaches are more robust and physically meaningful compared to the existing methods used to define drought indices. Still, framework is flexible with respect to the water balance, enabling users to adapt the index formulation to the data availability of different locations. Based on the framework, indices with different complex water balances are compared with each other. The comparison shows that a drought index considering only precipitation in the water balance is sufficient for Western to Central Europe. However, in the Mediterranean temperature effects via evapotranspiration need to be considered in order to produce meaningful indices representative of actual water deficit. Similarly, our results indicate that in north-eastern Europe and Scandinavia, snow and runoff effects needs to be considered in the index definition to obtain accurate results.
A general simulation model developing process based on five-object framework
Institute of Scientific and Technical Information of China (English)
胡安斌; 伞冶; 陈建明; 陈永强
2003-01-01
Different paradigms that relate verification and validation to the simulation model have different development process. A simulation model developing process based on Five-Object Framework (FOF) is discussed in this paper. An example is given to demonstrate the applications of the proposed method.
Energy Technology Data Exchange (ETDEWEB)
Xu, Z.; Bradley, D.P.; Jakes, P.J.
1994-06-20
The report summarizes the shortcomings of current natural resource accounting systems, outlines some of the features needed, and proposes an accounting framework that would help integrate economic and ecological factors. Such a system of forest resource accounting is urgently needed to achieve the sustainable goals of ecosystem management.
Maness, M.; Cirillo, C.; Dugundji, E.R.
2015-01-01
Over the past two decades, transportation has begun a shift from an individual focus to a social focus. Accordingly, discrete choice models have begun to integrate social context into its framework. Social influence, the process of having one’s behavior be affected by others, has been one approach t
Drageset, Ove Gunnar
2014-01-01
n order to describe and analyze teachers’ orchestrating of classroom discourse, detailed descriptions of teachers’ comments and questions are critical. The purpose of this article is to suggest new concepts that enable us to describe in detail how teachers use or do not use students’ comments to work with the mathematical content. Five teachers from upper primary school (grades five to seven, students aged 10 to 13) were studied. Beginning with the analysis of a pattern where the teacher give...
A General framework for the Synthesis and Operational Design of Batch Processes
DEFF Research Database (Denmark)
The objective of this paper is to present a general problem formulation and a general methodlogy for the synthesis of batch operations and the operational design of individual batch processes, such as mixing, reaction and separation. The general methodology described supplies the batch routes...
2014-12-01
An Evaluation of the Generalized Intelligent Framework for Tutoring (GIFT) from a Researcher’s or Analyst’s Perspective by Robert A...Sottilare, Anne M Sinatra, Julian Watson , Zachary Davis, Stefani King, and Michael D Matthews ARL-SR-0302 December 2014...to the originator. Army Research Laboratory Aberdeen Proving Ground, MD 21005-5425 ARL-SR-0302 December 2014 An Evaluation of the
Bhatnagar, S; Bhatnagar, Shashank; Li, Shi-Yuan
2006-01-01
We employ the framework of Bethe-Salpeter equation under Covariant Instantaneous Ansatz (CIA) to study the leptonic decays of vector mesons. The calculations of decay constants f_v for rho, phi and omega mesons have been performed adopting a generalized structure of the hadron-quark vertex function Gamma which is generalized to include various Dirac covariants (other than the leading covariant i gamma cdot epsilon) from the complete set of covariants in accordance with a naive power counting rule, which allows the incorporation of them order by order in powers of the inverse of the meson mass.
KMCLib: A general framework for lattice kinetic Monte Carlo (KMC) simulations
Leetmaa, Mikael; Skorodumova, Natalia V.
2014-09-01
KMCLib is a general framework for lattice kinetic Monte Carlo (KMC) simulations. The program can handle simulations of the diffusion and reaction of millions of particles in one, two, or three dimensions, and is designed to be easily extended and customized by the user to allow for the development of complex custom KMC models for specific systems without having to modify the core functionality of the program. Analysis modules and on-the-fly elementary step diffusion rate calculations can be implemented as plugins following a well-defined API. The plugin modules are loosely coupled to the core KMCLib program via the Python scripting language. KMCLib is written as a Python module with a backend C++ library. After initial compilation of the backend library KMCLib is used as a Python module; input to the program is given as a Python script executed using a standard Python interpreter. We give a detailed description of the features and implementation of the code and demonstrate its scaling behavior and parallel performance with a simple one-dimensional A-B-C lattice KMC model and a more complex three-dimensional lattice KMC model of oxygen-vacancy diffusion in a fluorite structured metal oxide. KMCLib can keep track of individual particle movements and includes tools for mean square displacement analysis, and is therefore particularly well suited for studying diffusion processes at surfaces and in solids. Catalogue identifier: AESZ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AESZ_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License, version 3 No. of lines in distributed program, including test data, etc.: 49 064 No. of bytes in distributed program, including test data, etc.: 1 575 172 Distribution format: tar.gz Programming language: Python and C++. Computer: Any computer that can run a C++ compiler and a Python interpreter. Operating system: Tested on Ubuntu 12
A Generalized Decision Framework Using Multi-objective Optimization for Water Resources Planning
Basdekas, L.; Stewart, N.; Triana, E.
2013-12-01
Colorado Springs Utilities (CSU) is currently engaged in an Integrated Water Resource Plan (IWRP) to address the complex planning scenarios, across multiple time scales, currently faced by CSU. The modeling framework developed for the IWRP uses a flexible data-centered Decision Support System (DSS) with a MODSIM-based modeling system to represent the operation of the current CSU raw water system coupled with a state-of-the-art multi-objective optimization algorithm. Three basic components are required for the framework, which can be implemented for planning horizons ranging from seasonal to interdecadal. First, a water resources system model is required that is capable of reasonable system simulation to resolve performance metrics at the appropriate temporal and spatial scales of interest. The system model should be an existing simulation model, or one developed during the planning process with stakeholders, so that 'buy-in' has already been achieved. Second, a hydrologic scenario tool(s) capable of generating a range of plausible inflows for the planning period of interest is required. This may include paleo informed or climate change informed sequences. Third, a multi-objective optimization model that can be wrapped around the system simulation model is required. The new generation of multi-objective optimization models do not require parameterization which greatly reduces problem complexity. Bridging the gap between research and practice will be evident as we use a case study from CSU's planning process to demonstrate this framework with specific competing water management objectives. Careful formulation of objective functions, choice of decision variables, and system constraints will be discussed. Rather than treating results as theoretically Pareto optimal in a planning process, we use the powerful multi-objective optimization models as tools to more efficiently and effectively move out of the inferior decision space. The use of this framework will help CSU
2014-01-01
In this paper we present a generic framework for ontology-based information retrieval. We focus on the recognition of semantic information extracted from data sources and the mapping of this knowledge into ontology. In order to achieve more scalability, we propose an approach for semantic indexing based on entity retrieval model. In addition, we have used ontology of public transportation domain in order to validate these proposals. Finally, we evaluated our system using ontology mapping and ...
Plasduino: an inexpensive, general purpose data acquisition framework for educational experiments
Baldini, L; Andreoni, E; Angelini, F; Bianchi, A; Bregeon, J; Fidecaro, F; Massai, M M; Merlin, V; Nespolo, J; Orselli, S; Pesce-Rollins, M
2013-01-01
Based on the Arduino development platform, Plasduino is an open-source data acquisition framework specifically designed for educational physics experiments. The source code, schematics and documentation are in the public domain under a GPL license and the system, streamlined for low cost and ease of use, can be replicated on the scale of a typical didactic lab with minimal effort. We describe the basic architecture of the system and illustrate its potential with some real-life examples.
GELATIO: a general framework for modular digital analysis of high-purity Ge detector signals
Agostini, M; Zavarise, P; Volynets, O
2011-01-01
GELATIO is a new software framework for advanced data analysis and digital signal processing developed for the GERDA neutrinoless double beta decay experiment. The framework is tailored to handle the full analysis flow of signals recorded by high purity Ge detectors and photo-multipliers from the veto counters. It is designed to support a multi-channel modular and flexible analysis, widely customizable by the user either via human-readable initialization files or via a graphical interface. The framework organizes the data into a multi-level structure, from the raw data up to the condensed analysis parameters, and includes tools and utilities to handle the data stream between the different levels. GELATIO is implemented in C++. It relies upon ROOT and its extension TAM, which provides compatibility with PROOF, enabling the software to run in parallel on clusters of computers or many-core machines. It was tested on different platforms and benchmarked in several GERDA-related applications. A stable version is pr...
Framework for a Robust General Purpose Navier-Stokes Solver on Unstructured Meshes
Xiao, Cheng-Nian; Denner, Fabian; van Wachem, Berend G. M.
2016-11-01
A numerical framework for a pressure-based all-speeds flow solver operating on unstructured meshes, which is robust for a broad range of flow configurations, is proposed. The distinct features of our framework are the full coupling of the momentum and continuity equations as well as the use of an energy equation in conservation form to relate the thermal quantities with the flow field. In order to overcome the well-documented instability occurring while coupling the thermal energy to the remaining flow variables, a multistage iteration cycle has been devised which exhibits excellent convergence behavior without requiring any numerical relaxation parameters. Different spatial schemes for accurate shock resolution as well as complex thermodynamic gas models are also seamlessly incorporated into the framework. The solver is directly applicable to stationary and transient flows in all Mach number regimes (sub-, trans-, supersonic), exhibits strong robustness and accurately predicts flow and thermal variables at all speeds across shocks of different strengths. We present a wide range of results for both steady and transient compressible flows with vastly different Mach numbers and thermodynamic conditions in complex geometries represented by different types of unstructured meshes. The authors are grateful for the financial support provided by Shell.
A generalized slab-wise framework for parallel transmit multiband RF pulse design
Wu, Xiaoping; Schmitter, Sebastian; Auerbach, Edward J.; Uğurbil, Kâmil; de Moortele, Pierre-François Van
2015-01-01
Purpose We propose a new slab-wise framework to design parallel transmit multi-band pulses for volumetric simultaneous multi-slice imaging with a large field of view along the slice direction (FOVs). Theory and Methods The slab-wise framework divides FOVs into a few contiguous slabs and optimizes pulses for each slab. Effects of relevant design parameters including slab number and transmit B1 (B1+) mapping slice placement were investigated for human brain imaging by designing pulses with global or local SAR control based on electromagnetic simulations of a 7T head RF array. Pulse design using in-vivo B1+ maps was demonstrated and evaluated with Bloch simulations. Results RF performance with respect to SAR reduction or B1+ homogenization across the entire human brain improved with increasing slabs; however, this improvement was non-linear and leveled off at ~12 slabs when the slab thickness reduced to ~12 mm. The impact of using different slice placements for B1+ mapping was small. Conclusion Compared to slice-wise approaches where each of the many imaging slices requires both B1+ mapping and pulse optimization, the proposed slab-wise design framework is shown to attain comparable RF performance while drastically reducing the number of required pulses; therefore, it can be used to increase time efficiency for B1+ mapping, pulse calculation and sequence preparation. PMID:25994797
Fujita, Shinsaku
2015-01-01
Chirality and stereogenicity are closely related concepts and their differentiation and description is still a challenge in chemoinformatics. A new stereoisogram approach, developed by the author, is introduced in this book, providing a theoretical framework for mathematical aspects of modern stereochemistry. The discussion covers point-groups and permutation symmetry and exemplifies the concepts using organic molecules and inorganic complexes.
Ing, Marsha
2016-01-01
Drawing inferences about the extent to which student performance reflects instructional opportunities relies on the premise that the measure of student performance is reflective of instructional opportunities. An instructional sensitivity framework suggests that some assessments are more sensitive to detecting differences in instructional…
Zhang, Zhilin; Pi, Zhouyue; Liu, Benyuan
2015-02-01
Heart rate monitoring using wrist-type photoplethysmographic signals during subjects' intensive exercise is a difficult problem, since the signals are contaminated by extremely strong motion artifacts caused by subjects' hand movements. So far few works have studied this problem. In this study, a general framework, termed TROIKA, is proposed, which consists of signal decomposiTion for denoising, sparse signal RecOnstructIon for high-resolution spectrum estimation, and spectral peaK trAcking with verification. The TROIKA framework has high estimation accuracy and is robust to strong motion artifacts. Many variants can be straightforwardly derived from this framework. Experimental results on datasets recorded from 12 subjects during fast running at the peak speed of 15 km/h showed that the average absolute error of heart rate estimation was 2.34 beat per minute, and the Pearson correlation between the estimates and the ground truth of heart rate was 0.992. This framework is of great values to wearable devices such as smartwatches which use PPG signals to monitor heart rate for fitness.
Measuring the Mathematical Quality of Instruction
Journal of Mathematics Teacher Education, 2011
2011-01-01
In this article, we describe a framework and instrument for measuring the mathematical quality of mathematics instruction. In describing this framework, we argue for the separation of the "mathematical quality of instruction" (MQI), such as the absence of mathematical errors and the presence of sound mathematical reasoning, from pedagogical…
Sargsyan, Ori
2010-08-01
The general coalescent tree framework is a family of models for determining ancestries among random samples of DNA sequences at a nonrecombining locus. The ancestral models included in this framework can be derived under various evolutionary scenarios. Here, a computationally tractable full-likelihood-based inference method for neutral polymorphisms is presented, using the general coalescent tree framework and the infinite-sites model for mutations in DNA sequences. First, an exact sampling scheme is developed to determine the topologies of conditional ancestral trees. However, this scheme has some computational limitations and to overcome these limitations a second scheme based on importance sampling is provided. Next, these schemes are combined with Monte Carlo integrations to estimate the likelihood of full polymorphism data, the ages of mutations in the sample, and the time of the most recent common ancestor. In addition, this article shows how to apply this method for estimating the likelihood of neutral polymorphism data in a sample of DNA sequences completely linked to a mutant allele of interest. This method is illustrated using the data in a sample of DNA sequences at the APOE gene locus.
A Gauge-Independent Mechanism for Confinement and Mass Gap: Part I -- The General Framework
Cherrington, J Wade
2009-01-01
We propose a gauge-independent mechanism for the area-law behavior of Wilson loop expectation values in terms of worldsheets spanning Wilson loops interacting with the spin foams that contribute to the vacuum partition function. The method uses an exact transformation of lattice-regularized Yang-Mills theory that is valid for all couplings. Within this framework, some natural conjectures can be made as to what physical mechanism enforces the confinement property in the continuum (weak coupling) limit. Details for the SU(2) case in three dimensions are provided in a companion paper.
A general framework for the synthesis and operational design of batch processes
DEFF Research Database (Denmark)
Papaeconomou, Eirini; Gani, Rafiqul; Jørgensen, Sten Bay
2002-01-01
, for the operational design of batch reactors. A case study involving the feasible operation of a batch reactor with multiple desirable and undesirable reactions and operational constraints is presented. Application results including verification of the generated operational sequences (alternatives) through dynamic......The objective of this paper is to present a general problem formulation and a general methodology for the synthesis of batch operations and the operational design of individual batch processes, such as mixing, reaction and separation. The general methodology described supplies the batch routes...
Energy Technology Data Exchange (ETDEWEB)
Sadjadi, Seyed Jafar [Department of Industrial Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)], E-mail: sjsadjadi@iust.ac.ir; Soltani, R. [Department of Industrial Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)
2009-11-15
We present a heuristic approach to solve a general framework of serial-parallel redundancy problem where the reliability of the system is maximized subject to some general linear constraints. The complexity of the redundancy problem is generally considered to be NP-Hard and the optimal solution is not normally available. Therefore, to evaluate the performance of the proposed method, a hybrid genetic algorithm is also implemented whose parameters are calibrated via Taguchi's robust design method. Then, various test problems are solved and the computational results indicate that the proposed heuristic approach could provide us some promising reliabilities, which are fairly close to optimal solutions in a reasonable amount of time.
2007-01-01
models such as Van der waals, Redlich - Kwong , Beattie-Bridgeman, Benedict-Web-Rubin, and virial models. Transport properties such as viscosity, thermal...problems (BVPs) and initial value problems (IVPs) regardless of their origin or fields of application has been the main thrust of this research. Previous...Successful applications of this new hpk framework have been presented in various areas of continuum mechanics to demonstrate the benefits of using this
Xu, Fei; Xu, Hong; Chen, Xiong; Wu, Dingcai; Wu, Yang; Liu, Hao; Gu, Cheng; Fu, Ruowen; Jiang, Donglin
2015-06-01
Ordered π-columns and open nanochannels found in covalent organic frameworks (COFs) could render them able to store electric energy. However, the synthetic difficulty in achieving redox-active skeletons has thus far restricted their potential for energy storage. A general strategy is presented for converting a conventional COF into an outstanding platform for energy storage through post-synthetic functionalization with organic radicals. The radical frameworks with openly accessible polyradicals immobilized on the pore walls undergo rapid and reversible redox reactions, leading to capacitive energy storage with high capacitance, high-rate kinetics, and robust cycle stability. The results suggest that channel-wall functional engineering with redox-active species will be a facile and versatile strategy to explore COFs for energy storage.
Students' Mathematical Noticing
Lobato, Joanne; Hohensee, Charles; Rhodehamel, Bohdan
2013-01-01
Even in simple mathematical situations, there is an array of different mathematical features that students can attend to or notice. What students notice mathematically has consequences for their subsequent reasoning. By adapting work from both cognitive science and applied linguistics anthropology, we present a focusing framework, which treats…
Mathematics, Programming, and STEM
Yeh, Andy; Chandra, Vinesh
2015-01-01
Learning mathematics is a complex and dynamic process. In this paper, the authors adopt a semiotic framework (Yeh & Nason, 2004) and highlight programming as one of the main aspects of the semiosis or meaning-making for the learning of mathematics. During a 10- week teaching experiment, mathematical meaning-making was enriched when primary…
Indian Academy of Sciences (India)
Soumen Pal; A K Bandyopadhyay; S Mukherjee; B N Samaddar; P G Pal
2011-07-01
Although existence of MgAl2O4–-Al2O3 solid solution has been reported in the past, the detailed interactions have not been explored completely. For the first time, we report here a mathematical framework for the detailed solid solution interactions of -Al2O3 in MgAl2O4 (spinel). To investigate the solid solubility of -Al2O3 in MgAl2O4, Mg–Al spinel (MgO–Al2O3; = 1, 1.5, 3, 4.5 and an arbitrary high value 30) precursors have been heat treated at 1000°C. Presence of only non-stoichiometric MgAl2O4 phase up to = 4.5 at 1000°C indicates that alumina (as -Al2O3) present beyond stoichiometry gets completely accommodated in MgAl2O4 in the form of solid solution. → alumina phase transformation and its subsequent separation from MgAl2O4 has been observed in the Mg–Al spinel powders ( > 1) when the 1000°C heat treated materials are calcined at 1200°C. In the mathematical framework, unit cell of MgAl2O4 (Mg8Al16O32) has been considered for the solid solution interactions (substitution of Mg2+ ions by Al3+ ions) with -Al2O3. It is suggested that combination of unit cells of MgAl2O4 takes part in the interactions when > 5 (MgO–Al2O3).
Singh, H. A.; Bitz, C. M.; Nusbaumer, J.; Noone, D. C.
2016-06-01
A new matrix operator framework is developed to analyze results from climate modeling studies that employ numerical water tracers (WTs), which track the movement of water in the aerial hydrological cycle from evaporation to precipitation. Model WT output is related to the fundamental equation of hydrology, and the moisture flux divergence is subdivided into the divergence of locally evaporated moisture and the convergence of remotely evaporated moisture. The formulation also separates locally and remotely sourced precipitation. The remote contribution (also the remote moisture convergence) may be further subdivided into zonal, meridional, intrabasin, and interbasin parts. This framework is applied to the preindustrial climate as simulated by a global climate model in which water has been tagged in 10° latitude bands in each of the major ocean basins, and in which each major land mass has been tagged separately. New insights from the method reveal fundamental differences between the major ocean basins in locally sourced precipitation, remotely sourced precipitation, and their relative partitioning. Per unit area, the subtropical Atlantic is the largest global moisture source, providing precipitable water to adjacent land areas and to the eastern Pacific tropics while retaining the least for in situ precipitation. Subtropical moisture is least divergent over the Pacific, which is the smallest moisture source (per unit area) for global land areas. Basins also differ in how subtropical moisture is partitioned between tropical, midlatitude, and land regions. Part II will apply this framework to hydrological cycle perturbations due to CO2 doubling.
Land Surface Verification Toolkit (LVT) - A Generalized Framework for Land Surface Model Evaluation
Kumar, Sujay V.; Peters-Lidard, Christa D.; Santanello, Joseph; Harrison, Ken; Liu, Yuqiong; Shaw, Michael
2011-01-01
Model evaluation and verification are key in improving the usage and applicability of simulation models for real-world applications. In this article, the development and capabilities of a formal system for land surface model evaluation called the Land surface Verification Toolkit (LVT) is described. LVT is designed to provide an integrated environment for systematic land model evaluation and facilitates a range of verification approaches and analysis capabilities. LVT operates across multiple temporal and spatial scales and employs a large suite of in-situ, remotely sensed and other model and reanalysis datasets in their native formats. In addition to the traditional accuracy-based measures, LVT also includes uncertainty and ensemble diagnostics, information theory measures, spatial similarity metrics and scale decomposition techniques that provide novel ways for performing diagnostic model evaluations. Though LVT was originally designed to support the land surface modeling and data assimilation framework known as the Land Information System (LIS), it also supports hydrological data products from other, non-LIS environments. In addition, the analysis of diagnostics from various computational subsystems of LIS including data assimilation, optimization and uncertainty estimation are supported within LVT. Together, LIS and LVT provide a robust end-to-end environment for enabling the concepts of model data fusion for hydrological applications. The evolving capabilities of LVT framework are expected to facilitate rapid model evaluation efforts and aid the definition and refinement of formal evaluation procedures for the land surface modeling community.
Land surface Verification Toolkit (LVT – a generalized framework for land surface model evaluation
Directory of Open Access Journals (Sweden)
S. V. Kumar
2012-02-01
Full Text Available Model evaluation and verification are key in improving the usage and applicability of simulation models for real-world applications. In this article, the development and capabilities of a formal system for land surface model evaluation called the Land surface Verification Toolkit (LVT is described. LVT is designed to provide an integrated environment for systematic land model evaluation and facilitates a range of verification approaches and analysis capabilities. LVT operates across multiple temporal and spatial scales and employs a large suite of in-situ, remotely sensed and other model and reanalysis datasets in their native formats. In addition to the traditional accuracy-based measures, LVT also includes uncertainty and ensemble diagnostics, information theory measures, spatial similarity metrics and scale decomposition techniques that provide novel ways for performing diagnostic model evaluations. Though LVT was originally designed to support the land surface modeling and data assimilation framework known as the Land Information System (LIS, it supports hydrological data products from non-LIS environments as well. In addition, the analysis of diagnostics from various computational subsystems of LIS including data assimilation, optimization and uncertainty estimation are supported within LVT. Together, LIS and LVT provide a robust end-to-end environment for enabling the concepts of model data fusion for hydrological applications. The evolving capabilities of LVT framework are expected to facilitate rapid model evaluation efforts and aid the definition and refinement of formal evaluation procedures for the land surface modeling community.
Generalized framework for a user-aware interactive texture segmentation system
Gururajan, Arunkumar; Sari-Sarraf, Hamed; Hequet, Eric
2012-07-01
We present a new framework for an interactive image delineation technique, which we term as interactive texture-snapping system (IT-SNAPS). One of the unique features of IT-SNAPS stems from the fact that it can effectively aid the user in accurately segmenting images with complex texture, without placing undue burden on the user. This is made possible through the formulation of IT-SNAPS, which enables it to be user-aware, i.e., it unobtrusively elicits information from the user during the segmentation process, and hence, adapts itself on-the-fly to the boundary being segmented. In addition to generating an accurate segmentation, it is shown that the framework of IT-SNAPS allows for extraction of useful information post-segmentation, which can potentially assist in the development of customized automatic segmentation algorithms. The afore mentioned features of IT-SNAPS are demonstrated on a set of texture images, as well as on a real-world biomedical application. Using appropriate segmentation protocols in conjunction with expert-provided ground truth, experiments are designed to quantitatively evaluate and compare the segmentation accuracy and user-friendliness of IT-SNAPS with another popular interactive segmentation technique. Promising results indicate the efficacy of IT-SNAPS and its potential to positively impact a broad spectrum of computer vision applications.
Land surface Verification Toolkit (LVT – a generalized framework for land surface model evaluation
Directory of Open Access Journals (Sweden)
S. V. Kumar
2012-06-01
Full Text Available Model evaluation and verification are key in improving the usage and applicability of simulation models for real-world applications. In this article, the development and capabilities of a formal system for land surface model evaluation called the Land surface Verification Toolkit (LVT is described. LVT is designed to provide an integrated environment for systematic land model evaluation and facilitates a range of verification approaches and analysis capabilities. LVT operates across multiple temporal and spatial scales and employs a large suite of in-situ, remotely sensed and other model and reanalysis datasets in their native formats. In addition to the traditional accuracy-based measures, LVT also includes uncertainty and ensemble diagnostics, information theory measures, spatial similarity metrics and scale decomposition techniques that provide novel ways for performing diagnostic model evaluations. Though LVT was originally designed to support the land surface modeling and data assimilation framework known as the Land Information System (LIS, it supports hydrological data products from non-LIS environments as well. In addition, the analysis of diagnostics from various computational subsystems of LIS including data assimilation, optimization and uncertainty estimation are supported within LVT. Together, LIS and LVT provide a robust end-to-end environment for enabling the concepts of model data fusion for hydrological applications. The evolving capabilities of LVT framework are expected to facilitate rapid model evaluation efforts and aid the definition and refinement of formal evaluation procedures for the land surface modeling community.
Resource Allocation in a Generalized Framework for Virtualized Heterogeneous Wireless Network
Directory of Open Access Journals (Sweden)
Bo Fan
2016-01-01
Full Text Available As a prevailing concept in 5G, virtualization provides efficient coordination among multiple radio access technologies (RATs and enables multiple service providers (SPs to share different RATs’ infrastructure. This paper proposes a generic framework for virtualizing heterogeneous wireless network with different RATs. A novel “VMAC” (virtualized medium access control concept is introduced to converge different RAT protocols and perform inter-RAT resource allocation. To suit the proposed framework, a virtualization based resource allocation scheme is devised. We formulate the problem as a mixed combinatorial optimization, which jointly considers network access and rate allocation. First, to solve the network access problem, “adaptability ratio” is developed to model the fact that different RATs possess different adaptability to different services. And a Grey Relational Analysis (GRA method is adopted to calculate the adaptability ratio. Second, services are modeled as players, bargaining for RAT resources in a Nash bargaining game. And a closed-form Nash bargaining solution (NBS is derived. Combining adaptability ratio with NBS, a novel resource allocation algorithm is devised. Through simulation, the superiority and feasibility of the proposed algorithm are validated.
PANSYSTEMS ANALYSIS: MATHEMATICS, METHODOLOGY,RELATIVITY AND DIALECTICAL THINKING
Institute of Scientific and Technical Information of China (English)
郭定和; 吴学谋; 冯向军; 李永礼
2001-01-01
Based on new analysis modes and new definitions with relative mathematization and simplification or strengthening forms for concepts of generalized systems,panderivatives , pansymmetry , panbox principle, pansystems relativity, etc. , the framework and related principles of pansystems methodology and pansystems relativity are developed. Related contents include: pansystems with relatively universal mathematizing forns, 200 types of dualities, duality transformation, pansymmetry transformation,pansystems dialectics, the 8-domain method, pansystems mathematical methods,generalized quantification, the principles of approximation-transforming, pan-equivalence theorems , supply-demand analysis, thinking experiment, generalized gray systems, etc.
Energy Technology Data Exchange (ETDEWEB)
Sommer, Elise Meister; Vargas, Jose Viriato Coelho [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Centro Politecnico. Setor de Tecnologia], Email: jvargas@demec.ufpr.br; Martins, Lauber de Souza; Ordonez, Juan Carlos [Florida State University, Tallahasse, FL (United States). Dept. of Mechanical Engineering and Center for Advanced Power Systems], Emails: martins@caps.fsu.edu, ordonez@eng.fsu.edu
2010-07-01
The Alkaline Membrane Fuel Cell (AMFC) is a recently developed fuel cell type, which has shown good experimental results in the laboratory. This paper introduces a mathematical model for the single AMFC with fixed volume and general square section. The main objective is to produce a reliable model (and computationally fast) to predict the response of the single AMFC according to variations of the physical properties of manufacturing materials and operating and design parameters. The model is based on mass, momentum, energy and species conservation, and electrochemical principles, and takes into account pressure drops in the gas channels and temperature gradients with respect to space in the flow direction. The simulation results comprise the AMFC temperature distribution, net power and polarization curves. It is shown that temperature spatial gradients and gas channels pressure drops significantly affect fuel cell performance. Such effects are not usually investigated in the models available in the literature, with most of them assuming uniform pressure and temperature operation. Therefore, the model is expected to be a useful tool for AMFC design and optimization. (author)
Vanbinst, K; De Smedt, B
2016-01-01
This contribution reviewed the available evidence on the domain-specific and domain-general neurocognitive determinants of children's arithmetic development, other than nonsymbolic numerical magnitude processing, which might have been overemphasized as a core factor of individual differences in mathematics and dyscalculia. We focused on symbolic numerical magnitude processing, working memory, and phonological processing, as these determinants have been most researched and their roles in arithmetic can be predicted against the background of brain imaging data. Our review indicates that symbolic numerical magnitude processing is a major determinant of individual differences in arithmetic. Working memory, particularly the central executive, also plays a role in learning arithmetic, but its influence appears to be dependent on the learning stage and experience of children. The available evidence on phonological processing suggests that it plays a more subtle role in children's acquisition of arithmetic facts. Future longitudinal studies should investigate these factors in concert to understand their relative contribution as well as their mediating and moderating roles in children's arithmetic development.
A General Framework for Representing, Reasoning and Querying with Annotated Semantic Web Data
Zimmermann, Antoine; Polleres, Axel; Straccia, Umberto
2011-01-01
We describe a generic framework for representing and reasoning with annotated Semantic Web data, a task becoming more important with the recent increased amount of inconsistent and non-reliable meta-data on the web. We formalise the annotated language, the corresponding deductive system and address the query answering problem. Previous contributions on specific RDF annotation domains are encompassed by our unified reasoning formalism as we show by instantiating it on (i) temporal, (ii) fuzzy, and (iii) provenance annotations. Moreover, we provide a generic method for combining multiple annotation domains allowing to represent, e.g. temporally-annotated fuzzy RDF. Furthermore, we address the development of a query language -- AnQL -- that is inspired by SPARQL, including several features of SPARQL 1.1 (subqueries, aggregates, assignment, solution modifiers) along with the formal definitions of their semantics.
Murray, James D
1993-01-01
The book is a textbook (with many exercises) giving an in-depth account of the practical use of mathematical modelling in the biomedical sciences. The mathematical level required is generally not high and the emphasis is on what is required to solve the real biological problem. The subject matter is drawn, e.g. from population biology, reaction kinetics, biological oscillators and switches, Belousov-Zhabotinskii reaction, reaction-diffusion theory, biological wave phenomena, central pattern generators, neural models, spread of epidemics, mechanochemical theory of biological pattern formation and importance in evolution. Most of the models are based on real biological problems and the predictions and explanations offered as a direct result of mathematical analysis of the models are important aspects of the book. The aim is to provide a thorough training in practical mathematical biology and to show how exciting and novel mathematical challenges arise from a genuine interdisciplinary involvement with the biosci...
Schindler, Maike; Rott, Benjamin
2017-01-01
Giftedness is an increasingly important research topic in educational sciences and mathematics education in particular. In this paper, we contribute to further theorizing mathematical giftedness through illustrating how networking processes can be conducted and illustrating their potential benefits. The paper focuses on two theories: Renzulli's…
A framework for investigating general patterns of benthic β-diversity along estuaries
Barros, Francisco; Blanchet, Hugues; Hammerstrom, Kamille; Sauriau, Pierre-Guy; Oliver, John
2014-08-01
The description of major patterns in beta (β) diversity is important in order to understand changes in community composition and/or richness at different spatial and temporal scales, and can interrogate processes driving species distribution and community dynamics. Human impacts have pushed many estuarine systems far from their historical baseline of rich, diverse, and productive ecosystems. Despite the ecological and social importance of estuaries, there has not yet been an attempt to investigate patterns of β-diversity and its partitioning along estuarine systems of different continents. We aimed to evaluate if benthic assemblages would show higher turnover than nestedness in tropical than in temperate systems, if well-known impacted estuaries would show greater nestedness than less polluted systems, and to propose a conceptual framework for studying benthic macrofauna beta diversity along estuaries. We analyzed subtidal benthic macrofaunal data from estuaries in Brazil, USA and France. We estimated alpha (α), beta (β) and gamma (γ) diversity for each sampling time in each system, investigated patterns of β -diversity as multivariate dispersion and the partitioning (nestedness and replacement) of β-diversity along each estuary. There was a decrease in the α-diversity along marine to freshwater conditions at most of the estuaries and sampling dates. Beta diversity as multivariate dispersion showed high variability. Most of the estuaries showed a greater proportion of the β-diversity driven by replacement than nestedness. We suggest a conceptual framework for estuaries where relatively pristine estuaries would have their β-diversity mostly driven by replacement while impacted estuaries subjected to several anthropogenic stressors would show total nestedness or total replacement, depending on the stress.
Energy Technology Data Exchange (ETDEWEB)
Albooyeh, M.; Tretyakov, Sergei [Department of Radio Science and Engineering, Aalto University, P.O. Box 13000, FI-00076, Aalto (Finland); Simovski, Constantin [Department of Radio Science and Engineering, Aalto University, P.O. Box 13000, FI-00076, Aalto (Finland); Laboratory of Metamaterials, University for Information Technology, Mechanics and Optics (ITMO), 197101, St. Petersburg (Russian Federation)
2016-10-15
We present a general methodology for electromagnetic homogenization and characterization of bianisotropic metasurfaces formed by regular or random arrangements of small arbitrary inclusions at interfaces of two different isotropic media. The approach unites and generalizes the earlier theories developed independently by two joint research groups: that of profs. Holloway and Kuester and that of profs. Simovski and Tretyakov. We analyze the features of both formalisms and discuss their peculiarities in several example cases. Our theory can be used in the analysis and synthesis of a wide spectrum of metasurfaces. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Pyburn, Daniel T.; Pazicni, Samuel
2014-01-01
Prior chemistry education research has demonstrated a relationship between student reading skill and general chemistry course performance. In addition to student characteristics, however, the qualities of the learning materials with which students interact also impact student learning. For example, low-knowledge students benefit from texts that…
A framework for general sparse matrix-matrix multiplication on GPUs and heterogeneous processors
DEFF Research Database (Denmark)
Liu, Weifeng; Vinter, Brian
2015-01-01
General sparse matrix-matrix multiplication (SpGEMM) is a fundamental building block for numerous applications such as algebraic multigrid method (AMG), breadth first search and shortest path problem. Compared to other sparse BLAS routines, an efficient parallel SpGEMM implementation has to handle...
Hubert, David A.; Lewis, Kati J.
2014-01-01
This essay presents the findings of an authentic and holistic assessment, using a random sample of one hundred student General Education ePortfolios, of two of Salt Lake Community College's (SLCC) college-wide learning outcomes: quantitative literacy (QL) and information literacy (IL). Performed by four faculty from biology, humanities, and…
Gulyaev, Sergei A.; Stonyer, Heather R.
2002-01-01
Develops an integrated approach based on the use of general systems theory (GST) and the concept of 'mapping' scientific knowledge to provide students with tools for a more holistic understanding of science. Uses GST as the core methodology for understanding science and its complexity. Discusses the role of scientific community in producing…
Pyburn, Daniel T.; Pazicni, Samuel
2014-01-01
Prior chemistry education research has demonstrated a relationship between student reading skill and general chemistry course performance. In addition to student characteristics, however, the qualities of the learning materials with which students interact also impact student learning. For example, low-knowledge students benefit from texts that…
Directory of Open Access Journals (Sweden)
J.C. Chrispell
2016-05-01
Full Text Available The development of appropriate water management strategies requires, in part, a methodology for quantifying and evaluating the impact of water policy decisions on regional stakeholders. In this work, we describe the framework we are developing to enhance the body of resources available to policy makers, farmers, and other community members in their e orts to understand, quantify, and assess the often competing objectives water consumers have with respect to usage. The foundation for the framework is the construction of a simulation-based optimization software tool using two existing software packages. In particular, we couple a robust optimization software suite (DAKOTA with the USGS MF-OWHM water management simulation tool to provide a flexible software environment that will enable the evaluation of one or multiple (possibly competing user-defined (or stakeholder objectives. We introduce the individual software components and outline the communication strategy we defined for the coupled development. We present numerical results for case studies related to crop portfolio management with several defined objectives. The objectives are not optimally satisfied for any single user class, demonstrating the capability of the software tool to aid in the evaluation of a variety of competing interests.
Fowler, K. R.; Jenkins, E.W.; Parno, M.; Chrispell, J.C.; Colón, A. I.; Hanson, Randall T.
2016-01-01
The development of appropriate water management strategies requires, in part, a methodology for quantifying and evaluating the impact of water policy decisions on regional stakeholders. In this work, we describe the framework we are developing to enhance the body of resources available to policy makers, farmers, and other community members in their e orts to understand, quantify, and assess the often competing objectives water consumers have with respect to usage. The foundation for the framework is the construction of a simulation-based optimization software tool using two existing software packages. In particular, we couple a robust optimization software suite (DAKOTA) with the USGS MF-OWHM water management simulation tool to provide a flexible software environment that will enable the evaluation of one or multiple (possibly competing) user-defined (or stakeholder) objectives. We introduce the individual software components and outline the communication strategy we defined for the coupled development. We present numerical results for case studies related to crop portfolio management with several defined objectives. The objectives are not optimally satisfied for any single user class, demonstrating the capability of the software tool to aid in the evaluation of a variety of competing interests.
Directory of Open Access Journals (Sweden)
Nistor Cristina
2011-12-01
Full Text Available The importance of accounting in the modern economy is obvious. That is more elevated bodies of the European Union and elsewhere dealing with the organization and functioning of accounting as a fundamental component of business (Nistor C., 2009. The mission of the International Federation of Accountants (IFAC is to serve the public interest, strengthen the worldwide accountancy profession and contribute to the development of strong international economies by initiating and encouraging the professional standards of high quality, the convergence process these international standards and to discuss issues of public interest which is extremely relevant international experience of (IFAC, 2011. Currently, the concepts related to financial reports in public sector are developed by IPSAS references. Many of today's IPSAS are based on international accounting standards (IAS / IFRS, to the extent that they are relevant to the requirements of the public sector. Therefore today's IPSAS are based on concepts and definitions of the IASB's conceptual framework, with changes where necessary for public sector specific approach. Thus this study present this brief draft statement under discussion by the leadership of IFAC in collaboration with other organizations and groups that develop financial reporting requirements of the public sector. Then, we highlight the importance and the degree of acceptance of the project which results from comments received. On the basis of combining qualitative with quantitative research seeks to demonstrate the necessity and usefulness of a common conceptual framework of the International Accounting Standards (in this case the Public Sector, starting from their emergence from presenting their bodies involved in the foundation, the content standards, experience of different countries. The results have direct implications on Romanian public accounting system, given that the reference of the international implementation and reporting is
Handley, Bill
2012-01-01
This new, revised edition of the bestselling Speed Mathematics features new chapters on memorising numbers and general information, calculating statistics and compound interest, square roots, logarithms and easy trig calculations. Written so anyone can understand, this book teaches simple strategies that will enable readers to make lightning-quick calculations. People who excel at mathematics use better strategies than the rest of us; they are not necessarily more intelligent. With Speed Mathematics you'll discover methods to make maths easy and fun. This book is perfect for stud
Gravitational Wave Tests of General Relativity with the Parameterized Post-Einsteinian Framework
Cornish, Neil; Yunes, Nico; Pretorius, Frans
2011-01-01
Gravitational wave astronomy has tremendous potential for studying extreme astrophysical phenomena and exploring fundamental physics. The waves produced by binary black hole mergers will provide a pristine environment in which to study strong field, dynamical gravity. Extracting detailed information about these systems requires accurate theoretical models of the gravitational wave signals. If gravity is not described by General Relativity, analyses that are based on waveforms derived from Einstein's field equations could result in parameter biases and a loss of detection efficiency. A new class of "parameterized post-Einsteinian" (ppE) waveforms has been proposed to cover this eventuality. Here we apply the ppE approach to simulated data from a network of advanced ground based interferometers (aLIGO/aVirgo) and from a future spaced based interferometer (LISA). Bayesian inference and model selection are used to investigate parameter biases, and to determine the level at which departures from general relativity...
Axially symmetric static sources: A general framework and some analytical solutions
Herrera, L; Ibañez, J; Ospino, J
2013-01-01
We provide all basic equations and concepts required to carry out a general study on axially symmetric static sources. The Einstein equations and the conservation equations are written down for a general anisotropic static fluid endowed with axial symmetry. The structure scalars are calculated and the inhomogeneity factors are identified. Finally some exact analytical solutions were found. One of these solutions describes an incompressible spheroid with isotropic pressure and becomes the well known interior Schwarzschild solution in the spherically symmetric limit, however it cannot be matched smoothly to any Weyl exterior metric. Another family of solutions was found that corresponds to an anisotropic fluid distribution and can in principle be matched to a Weyl exterior.
A generalized Defries-Fulker regression framework for the analysis of twin data.
Lazzeroni, Laura C; Ray, Amrita
2013-01-01
Twin studies compare the similarity between monozygotic twins to that between dizygotic twins in order to investigate the relative contributions of latent genetic and environmental factors influencing a phenotype. Statistical methods for twin data include likelihood estimation and Defries-Fulker regression. We propose a new generalization of the Defries-Fulker model that fully incorporates the effects of observed covariates on both members of a twin pair and is robust to violations of the Normality assumption. A simulation study demonstrates that the method is competitive with likelihood analysis. The Defries-Fulker strategy yields new insight into the parameter space of the twin model and provides a novel, prediction-based interpretation of twin study results that unifies continuous and binary traits. Due to the simplicity of its structure, extensions of the model have the potential to encompass generalized linear models, censored and truncated data; and gene by environment interactions.
AULISA, EUGENIO
2009-08-01
Motivated by the reservoir engineering concept of the well Productivity Index, we introduced and analyzed a functional, denoted as "diffusive capacity", for the solution of the initial-boundary value problem (IBVP) for a linear parabolic equation.21 This IBVP described laminar (linear) Darcy flow in porous media; the considered boundary conditions corresponded to different regimes of the well production. The diffusive capacities were then computed as steady state invariants of the solutions to the corresponding time-dependent boundary value problem. Here similar features for fast or turbulent nonlinear flows subjected to the Forchheimer equations are analyzed. It is shown that under some hydrodynamic and thermodynamic constraints, there exists a so-called pseudo steady state regime for the Forchheimer flows in porous media. In other words, under some assumptions there exists a steady state invariant over a certain class of solutions to the transient IBVP modeling the Forchheimer flow for slightly compressible fluid. This invariant is the diffusive capacity, which serves as the mathematical representation of the so-called well Productivity Index. The obtained results enable computation of the well Productivity Index by resolving a single steady state boundary value problem for a second-order quasilinear elliptic equation. Analytical and numerical studies highlight some new relations for the well Productivity Index in linear and nonlinear cases. The obtained analytical formulas can be potentially used for the numerical well block model as an analog of Piecemann. © 2009 World Scientific Publishing Company.
Unification of Electromagnetism and Gravitation in the Framework of General Geometry
Shahverdiyev, Shervgi
2005-01-01
A new geometry, called General geometry, is constructed. It is proven that its the most simplest special case is geometry underlying Electromagnetism. Another special case is Riemannian geometry. Action for electromagnetic field and Maxwell equations are derived from curvature function of geometry underlying Electromagnetism. It is shown that equation of motion for a particle interacting with electromagnetic field coincides exactly with equation for geodesics of geometry underlying Electromag...
Time-periodic solutions of the Einstein’s field equations Ⅰ:general framework
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
In this paper,we develop a new algorithm to find the exact solutions of the Einstein’s field equations.Time-periodic solutions are constructed by using the new algorithm.The singularities of the time-periodic solutions are investigated and some new physical phenomena,such as degenerate event horizon and time-periodic event horizon,are found.The applications of these solutions in modern cosmology and general relativity are expected.
Chiusole, Daniela; Cioffredi, Piero; Basso, Umberto; Bortolami, Alberto; Crivellari, Gino; Gennaro, Gisella; Spina, Romina; Opocher, Giuseppe
2015-01-01
The aim of this article is to describe the accreditation process of the Veneto Institute of Oncology (IOV-IRCCS) according to the Organisation of European Cancer Institutes (OECI) model, with particular reference to the standards for the multidisciplinary approach. Through the analysis of the process and the activities of each multidisciplinary team (MDT) and the development, at a regional level, of diagnostic, therapeutic, and care pathways (PDTA), all the necessary steps to meet the OECI standards have been determined. Adjustment is ongoing. We are working on the inclusion of the MDT registration forms in the electronic medical records and on the possibility to extend the OECI model to the MDT not based at IOV, but participated in by IOV professionals. The sarcoma MDT has achieved results demonstrating that the OECI framework has allowed the professionals involved in the multidisciplinary meeting to systematically share the clinical information of the patient, who can benefit from better continuity of care. The model has also provided greater clarity in the management of patients who are enrolled in clinical trials and deviate from Guide Lines (GL)/PDTA. The accreditation process according to the OECI model has added value to the IOV's already well-developed multidisciplinary activities.
Star Cluster Demographics. I. A General Framework and Application to the Antennae Galaxies
Whitmore, B C; Fall, S M; Whitmore, Bradley C.; Chandar, Rupali
2006-01-01
We present a framework for understanding the demographics of star cluster systems, and develop a toy model which incorporates a universal initial power law mass function, selected formation histories, selected disruption laws, and a convolution with common artifacts and selection effects found in observational data. The model confirms that the observed correlation between the brightest young cluster in a galaxy and the total number of young clusters can be understood as a statistical size-of-sample effect, rather than a difference in the physical process responsible for the formation of the clusters. A comparison is made between different cluster disruption laws and it is shown that the break in the dN/d\\tau diagram used to determine the parameters in the Boutloukos & Lamers model may be produced by incompleteness near the breakpoint. A model of the Antennae galaxies is developed and compared with the observational data. An important component of our model is the use of a "two-stage" disruption process, w...
How do general psychological processes inform FLL pedagogy? Presenting a new instructional framework
Directory of Open Access Journals (Sweden)
Michał B. Paradowski
2008-02-01
Full Text Available Learning invariably proceeds by relating new facts to the already familiar and present in the conceptual structure. In the context of FL study the familiar is, of course, the student’s mother tongue. Drawing on the learner’s L1 (or another mastered tongue and showing comparisons and contrasts between the languages mirrors, facilitates and accelerates the processes which occur independently in his/her mind. At the same time, when in a new situation, we look for familiar orientation points and similarities owing to our instinctive need for safety. This is also why the target language should literally be taught in the framework of the learner’s L1. Instruction in the Language Interface Model (LIM; Gozdawa-Gołębiowski 2003a,b, 2004a,b, 2005 proceeds from an explication of how relevant rules operate in the students’ L1 through an explanation of corresponding L2 rules and subsequent interface formation, modifying the L1 rule to accommodate L2 data, with practice first expecting the learner to apply the FL rules to L1 examples before moving to more traditional exercises, to finally end with competence expansion – integrating the two competences, leading to the development of multicompetence and allowing for the obliteration of the rules governing the structure of the utterance from the learner’s conscious mind.
A generalized framework for quantifying the dynamics of EEG event-related desynchronization.
Directory of Open Access Journals (Sweden)
Steven Lemm
2009-08-01
Full Text Available Brains were built by evolution to react swiftly to environmental challenges. Thus, sensory stimuli must be processed ad hoc, i.e., independent--to a large extent--from the momentary brain state incidentally prevailing during stimulus occurrence. Accordingly, computational neuroscience strives to model the robust processing of stimuli in the presence of dynamical cortical states. A pivotal feature of ongoing brain activity is the regional predominance of EEG eigenrhythms, such as the occipital alpha or the pericentral mu rhythm, both peaking spectrally at 10 Hz. Here, we establish a novel generalized concept to measure event-related desynchronization (ERD, which allows one to model neural oscillatory dynamics also in the presence of dynamical cortical states. Specifically, we demonstrate that a somatosensory stimulus causes a stereotypic sequence of first an ERD and then an ensuing amplitude overshoot (event-related synchronization, which at a dynamical cortical state becomes evident only if the natural relaxation dynamics of unperturbed EEG rhythms is utilized as reference dynamics. Moreover, this computational approach also encompasses the more general notion of a "conditional ERD," through which candidate explanatory variables can be scrutinized with regard to their possible impact on a particular oscillatory dynamics under study. Thus, the generalized ERD represents a powerful novel analysis tool for extending our understanding of inter-trial variability of evoked responses and therefore the robust processing of environmental stimuli.
The Justice Dimension of Sustainability: A Systematic and General Conceptual Framework
Directory of Open Access Journals (Sweden)
Klara Helene Stumpf
2015-06-01
Full Text Available We discuss how the normative dimension of sustainability can be captured in terms of justice. We (i identify the core characteristics of the concept of sustainability and discuss underlying ethical, ontological and epistemological assumptions; (ii introduce a general conceptual structure of justice for the analysis and comparison of different conceptions of justice; and (iii employ this conceptual structure to determine the specific characteristics and challenges of justice in the context of sustainability. We demonstrate that sustainability raises specific and partly new challenges of justice regarding the community of justice, the judicandum, the informational base, the principles, and the instruments of justice.
ELPSA as A Lesson Design Framework
Directory of Open Access Journals (Sweden)
Tom Lowrie
2015-07-01
Full Text Available This paper offers a framework for mathematics lesson design that is consistent with the way we learn about, and discover, most things in life. In addition, the framework provides a structure for identifying how mathematical concepts and understanding are acquired and developed. This framework is called ELPSA and represents five learning components, namely: Experience, Language, Pictorial, Symbolic and Applications. This framework has been used in developing lessons and teacher professional programs in Indonesia since 2012 in cooperation with the World Bank. This paper describes the theory that underlines the framework in general and in relation to each inter-connected component. Two explicit learning sequences for classroom practice are described, associated with Pythagoras theorem and probability. This paper then concludes with recommendations for using ELPSA in various institutional contexts.
Maier, Dieter; Kalus, Wenzel; Wolff, Martin; Kalko, Susana G; Roca, Josep; Marin de Mas, Igor; Turan, Nil; Cascante, Marta; Falciani, Francesco; Hernandez, Miguel; Villà-Freixa, Jordi; Losko, Sascha
2011-03-05
To enhance our understanding of complex biological systems like diseases we need to put all of the available data into context and use this to detect relations, pattern and rules which allow predictive hypotheses to be defined. Life science has become a data rich science with information about the behaviour of millions of entities like genes, chemical compounds, diseases, cell types and organs, which are organised in many different databases and/or spread throughout the literature. Existing knowledge such as genotype-phenotype relations or signal transduction pathways must be semantically integrated and dynamically organised into structured networks that are connected with clinical and experimental data. Different approaches to this challenge exist but so far none has proven entirely satisfactory. To address this challenge we previously developed a generic knowledge management framework, BioXM™, which allows the dynamic, graphic generation of domain specific knowledge representation models based on specific objects and their relations supporting annotations and ontologies. Here we demonstrate the utility of BioXM for knowledge management in systems biology as part of the EU FP6 BioBridge project on translational approaches to chronic diseases. From clinical and experimental data, text-mining results and public databases we generate a chronic obstructive pulmonary disease (COPD) knowledge base and demonstrate its use by mining specific molecular networks together with integrated clinical and experimental data. We generate the first semantically integrated COPD specific public knowledge base and find that for the integration of clinical and experimental data with pre-existing knowledge the configuration based set-up enabled by BioXM reduced implementation time and effort for the knowledge base compared to similar systems implemented as classical software development projects. The knowledgebase enables the retrieval of sub-networks including protein
Directory of Open Access Journals (Sweden)
Falciani Francesco
2011-03-01
Full Text Available Abstract Background To enhance our understanding of complex biological systems like diseases we need to put all of the available data into context and use this to detect relations, pattern and rules which allow predictive hypotheses to be defined. Life science has become a data rich science with information about the behaviour of millions of entities like genes, chemical compounds, diseases, cell types and organs, which are organised in many different databases and/or spread throughout the literature. Existing knowledge such as genotype - phenotype relations or signal transduction pathways must be semantically integrated and dynamically organised into structured networks that are connected with clinical and experimental data. Different approaches to this challenge exist but so far none has proven entirely satisfactory. Results To address this challenge we previously developed a generic knowledge management framework, BioXM™, which allows the dynamic, graphic generation of domain specific knowledge representation models based on specific objects and their relations supporting annotations and ontologies. Here we demonstrate the utility of BioXM for knowledge management in systems biology as part of the EU FP6 BioBridge project on translational approaches to chronic diseases. From clinical and experimental data, text-mining results and public databases we generate a chronic obstructive pulmonary disease (COPD knowledge base and demonstrate its use by mining specific molecular networks together with integrated clinical and experimental data. Conclusions We generate the first semantically integrated COPD specific public knowledge base and find that for the integration of clinical and experimental data with pre-existing knowledge the configuration based set-up enabled by BioXM reduced implementation time and effort for the knowledge base compared to similar systems implemented as classical software development projects. The knowledgebase enables the
A General Simulation Framework for Supply Chain Modeling: State of the Art and Case Study
Directory of Open Access Journals (Sweden)
Antonio Cimino
2010-03-01
Full Text Available Nowadays there is a large availability of discrete event simulation software that can be easily used in different domains: from industry to supply chain, from healthcare to business management, from training to complex systems design. Simulation engines of commercial discrete event simulation software use specific rules and logics for simulation time and events management. Difficulties and limitations come up when commercial discrete event simulation software are used for modeling complex real world-systems (i.e. supply chains, industrial plants. The objective of this paper is twofold: first a state of the art on commercial discrete event simulation software and an overview on discrete event simulation models development by using general purpose programming languages are presented; then a Supply Chain Order Performance Simulator (SCOPS, developed in C++ for investigating the inventory management problem along the supply chain under different supply chain scenarios is proposed to readers.
ECONOMETRIC APPROACH OF HETEROSKEDASTICITY ON FINANCIAL TIME SERIES IN A GENERAL FRAMEWORK
Directory of Open Access Journals (Sweden)
FELICIA RAMONA BIRĂU
2012-12-01
Full Text Available The aim of this paper is to provide an overview of the diagnostic tests for detecting heteroskedasticity on financial time series. In financial econometrics, heteroskedasticity is generally associated with cross sectional data but can also be identified modeling time series data. The presence of heteroscedasticity in financial time series can be caused by certain specific factors, like a model misspecification, inadequate data transformation or as a result of certain outliers. Heteroskedasticity arise when the homoskedasticity assumption is violated. Testing for the presence of heteroskedasticity in financial time is performed by applying diagnostic test, such as : Breusch-Pagan LM test, White’s test, Glesjer LM test, Harvey-Godfrey LM test, Park LM test and Goldfeld-Quand test.
Energy Technology Data Exchange (ETDEWEB)
Andrzejewski, D; Zhu, X; Craven, M; Recht, B
2011-01-18
Topic models have been used successfully for a variety of problems, often in the form of application-specific extensions of the basic Latent Dirichlet Allocation (LDA) model. Because deriving these new models in order to encode domain knowledge can be difficult and time-consuming, we propose the Fold-all model, which allows the user to specify general domain knowledge in First-Order Logic (FOL). However, combining topic modeling with FOL can result in inference problems beyond the capabilities of existing techniques. We have therefore developed a scalable inference technique using stochastic gradient descent which may also be useful to the Markov Logic Network (MLN) research community. Experiments demonstrate the expressive power of Fold-all, as well as the scalability of our proposed inference method.
A General Simulation Framework for Supply Chain Modeling: State of the Art and Case Study
Cimino, Antonio; Mirabelli, Giovanni
2010-01-01
Nowadays there is a large availability of discrete event simulation software that can be easily used in different domains: from industry to supply chain, from healthcare to business management, from training to complex systems design. Simulation engines of commercial discrete event simulation software use specific rules and logics for simulation time and events management. Difficulties and limitations come up when commercial discrete event simulation software are used for modeling complex real world-systems (i.e. supply chains, industrial plants). The objective of this paper is twofold: first a state of the art on commercial discrete event simulation software and an overview on discrete event simulation models development by using general purpose programming languages are presented; then a Supply Chain Order Performance Simulator (SCOPS, developed in C++) for investigating the inventory management problem along the supply chain under different supply chain scenarios is proposed to readers.
Blaha, S
2003-01-01
A study of the Great Zimbabwe Sub-Saharan civilization, Mayan civilization and other prehistoric civilizations within the framework of a mathematical macro theory of civilizations. We show these isolated and early civilizations conform to the general mathematical theory of civilizations in detail.
P-V criticality of AdS black holes in a general framework
Majhi, Bibhas Ranjan; Samanta, Saurav
2017-10-01
In black hole thermodynamics, it has been observed that AdS black holes behave as van der Waals system if one interprets the cosmological constant as a pressure term. Also the critical exponents for the phase transition of AdS black holes and the van der Waals systems are same. Till now this type of analysis is done by two steps. In the first step one shows that a particular metric allows phase transition and in the second step, using this information, one calculates the exponents. Here, we present a different approach based on two universal inputs (the general forms of the Smarr formula and the first law of thermodynamics) and one assumption regarding the existence of van der Waals like critical point for a metric. We find that the same values of the critical exponents can be obtained by this approach. Thus we demonstrate that, though the existence of van der Waals like phase transition depends on specific metrics, the values of critical exponents are then fixed for that set of metrics.
Bennett, C.; Poole, G. C.; Kimball, J. S.; Stanford, J. A.; O'Daniel, S. J.; Mertes, L. A.
2005-05-01
Historically, physical scientists have developed models with highly accurate governing equations, while biologists have excelled at abstraction (the strategic simplification of system complexity). These different modeling paradigms yield biological (e.g. food web) and physical (e.g. hydrologic) models that can be difficult to integrate. Complex biological dynamics may be impossible to represent with governing equations. Conversely, physical processes may be oversimplified in biological models. Using agent-based modeling, a technique applied widely in social sciences and economics, we are developing a general modeling system to integrate accurate representations of physical dynamics such as water and heat flux with abstracted biological processes such as nutrient transformations. The modeling system represents an ecosystem as a complex integrated network of intelligent physical and biological "agents" that store, transform, and trade ecosystem resources (e.g., water, heat, nutrients, carbon) using equations that describe either abstracted concepts and/or physical laws. The modular design of the system allows resource submodels to be developed independently and installed into the simulation architecture. The modeling system provides a useful heuristic tool to support integrated physical and biological research topics, such as the influence of hydrologic dynamics and spatio-temporal physical heterogeneity on trophic (food web) dynamics and/or nutrient cycling.
Directory of Open Access Journals (Sweden)
Yan-Gang Miao
2015-01-01
Full Text Available As a generalized uncertainty principle (GUP leads to the effects of the minimal length of the order of the Planck scale and UV/IR mixing, some significant physical concepts and quantities are modified or corrected correspondingly. On the one hand, we derive the maximally localized states—the physical states displaying the minimal length uncertainty associated with a new GUP proposed in our previous work. On the other hand, in the framework of this new GUP we calculate quantum corrections to the thermodynamic quantities of the Schwardzschild black hole, such as the Hawking temperature, the entropy, and the heat capacity, and give a remnant mass of the black hole at the end of the evaporation process. Moreover, we compare our results with that obtained in the frameworks of several other GUPs. In particular, we observe a significant difference between the situations with and without the consideration of the UV/IR mixing effect in the quantum corrections to the evaporation rate and the decay time. That is, the decay time can greatly be prolonged in the former case, which implies that the quantum correction from the UV/IR mixing effect may give rise to a radical rather than a tiny influence to the Hawking radiation.
Suryawanshi, Gajendra W; Hoffmann, Alexander
2015-12-07
Human immunodeficiency virus-1 (HIV-1) employs accessory proteins to evade innate immune responses by neutralizing the anti-viral activity of host restriction factors. Apolipoprotein B mRNA-editing enzyme 3G (APOBEC3G, A3G) and bone marrow stromal cell antigen 2 (BST2) are host resistance factors that potentially inhibit HIV-1 infection. BST2 reduces viral production by tethering budding HIV-1 particles to virus producing cells, while A3G inhibits the reverse transcription (RT) process and induces viral genome hypermutation through cytidine deamination, generating fewer replication competent progeny virus. Two HIV-1 proteins counter these cellular restriction factors: Vpu, which reduces surface BST2, and Vif, which degrades cellular A3G. The contest between these host and viral proteins influences whether HIV-1 infection is established and progresses towards AIDS. In this work, we present an age-structured multi-scale viral dynamics model of in vivo HIV-1 infection. We integrated the intracellular dynamics of anti-viral activity of the host factors and their neutralization by HIV-1 accessory proteins into the virus/cell population dynamics model. We calculate the basic reproductive ratio (Ro) as a function of host-viral protein interaction coefficients, and numerically simulated the multi-scale model to understand HIV-1 dynamics following host factor-induced perturbations. We found that reducing the influence of Vpu triggers a drop in Ro, revealing the impact of BST2 on viral infection control. Reducing Vif׳s effect reveals the restrictive efficacy of A3G in blocking RT and in inducing lethal hypermutations, however, neither of these factors alone is sufficient to fully restrict HIV-1 infection. Interestingly, our model further predicts that BST2 and A3G function synergistically, and delineates their relative contribution in limiting HIV-1 infection and disease progression. We provide a robust modeling framework for devising novel combination therapies that target
Hudson, H. T.; Liberman, Dov
1982-12-01
Precourse tests of computational skills in algebra and trigonometry and of formal operational reasoning have been correlated with performance in the algebra-based introductory physics course for 80 students. The correlation coefficient for mathematics and physics was 0.345 (p<0.001) and for formal operational reasoning and physics was 0.435 (p<0.001). However, a multiple regression analysis of the combined effect of mathematics and formal operational reasoning on the total physics grade yielded a multiple R of 0.518, R2=0.268. This study found that the combination of precourse measures of mathematics computational skills and abstract reasoning explained over 25% of the variance in the final physics grade distribution.
Institute of Scientific and Technical Information of China (English)
刘达; 徐炜蓉; 陈吉
2014-01-01
本文通过分析PISA2012数学测评框架后发现，该框架中的数学素养被重新界定，内容维度和情境维度都延续了2003年的框架，变化最大的是过程维度，它采用“三种过程+七种基本数学能力”的二维结构。本文在总结该框架优点的基础上，借鉴框架和PISA评分细则设计的核心理念，对上海市2013年初中学业水平考试一道试题进行改编和试测，发现改编后的试题更有利于精准地检测出学生的薄弱能力点，从而有助于老师改进教学。%After reviewing the PISA2012 Mathematics Literacy Assessment Framework, it is concluded that the mathematics literacy was redefined, and the expression of the process dimension changed significantly, while the content dimension and the context dimension kept the same as the PISA2003 Mathematics Literacy Assessment Framework. This research summarized the advantages of the PISA2012 framework, revised and trial an item in 2013 Shanghai Junior High School Graduation Test based on the framework and core concepts for the designing of the PISA mathematics item rubrics. It was founded that after being revised the item was more efficient to assess the weak points of the test takers’ competency while they went through the mathematics process, which could contribute to the relative teaching improvement.
Energy Technology Data Exchange (ETDEWEB)
Mavrotas, George; Diakoulaki, Danae; Florios, Kostas; Georgiou, Paraskevas [Laboratory of Industrial and Energy Economics, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 15780 Athens (Greece)
2008-07-15
The aim of this paper is to provide an integrated modeling and optimization framework for energy planning in large consumers of the services' sector based on mathematical programming. The power demand is vaguely known and the underlying uncertainty is modeled using elements from fuzzy set theory. The defined fuzzy programming model is subsequently transformed to an equivalent multi-objective problem, where the minimization of cost and the maximization of demand satisfaction are the objective functions. The Pareto optimal solutions of this problem are obtained using a novel version of the {epsilon}-constraint method and represent the possibly optimal solutions of the original problem under uncertainty. In the present case, in order to select the most preferred Pareto optimal solution, the minimax regret criterion is properly used to indicate the preferred configuration of the system (i.e. the size of the installed units) given the load uncertainty. Furthermore, the paper proposes a model reduction technique that can be used in similar cases and further examines its effect in the final results. The above methodology is applied to the energy rehabilitation of a hospital in the Athens area. The technologies under consideration include a combined heat and power unit for providing power and heat, an absorption unit and/or a compression unit for providing cooling load. The obtained results demonstrate that, increasing the degree of demand satisfaction, the total annual cost increases almost linearly. Although data compression allows obtaining realistic results, the size of the proposed units might be slightly changed. (author)
Janssen, Paddy K.C.
2016-01-01
Purpose To find the most accurate mathematical description of the intravaginal ejaculation latency time (IELT) distribution in the general male population. Materials and Methods We compared the fitness of various well-known mathematical distributions with the IELT distribution of two previously published stopwatch studies of the Caucasian general male population and a stopwatch study of Dutch Caucasian men with lifelong premature ejaculation (PE). The accuracy of fitness is expressed by the Goodness of Fit (GOF). The smaller the GOF, the more accurate is the fitness. Results The 3 IELT distributions are gamma distributions, but the IELT distribution of lifelong PE is another gamma distribution than the IELT distribution of men in the general male population. The Lognormal distribution of the gamma distributions most accurately fits the IELT distribution of 965 men in the general population, with a GOF of 0.057. The Gumbel Max distribution most accurately fits the IELT distribution of 110 men with lifelong PE with a GOF of 0.179. There are more men with lifelong PE ejaculating within 30 and 60 seconds than can be extrapolated from the probability density curve of the Lognormal IELT distribution of men in the general population. Conclusions Men with lifelong PE have a distinct IELT distribution, e.g., a Gumbel Max IELT distribution, that can only be retrieved from the general male population Lognormal IELT distribution when thousands of men would participate in a IELT stopwatch study. The mathematical formula of the Lognormal IELT distribution is useful for epidemiological research of the IELT. PMID:26981594
Directory of Open Access Journals (Sweden)
Maike Schindler
2016-12-01
Full Text Available Giftedness is an increasingly important research topic in educational sciences and mathematics education in particular. In this paper, we contribute to further theorizing mathematical giftedness through illustrating how networking processes can be conducted and illustrating their potential benefits. The paper focuses on two theories: Renzulli’s domain-general theory on giftedness as an interplay of creativity, above-average ability, and task commitment; and Krutetskii’s mathematics-specific theory on gifted students’ abilities. In a “proof of concept”, we illustrate how the abilities offered in Krutetskii’s theory can be mapped to the three traits described by Renzulli. This is realized through a mapping process in which two raters independently mapped the abilities offered by Krutetskii to Renzulli’s traits. The results of this mapping give first insights into (a possible mappings of Krutetskii’s abilities to Renzulli’s traits and, thus, (b a possible domain-specific specification of Renzulli’s theory. This mapping hints at interesting potential phenomena: in Krutetskii’s theory, above-average ability appears to be the trait that predominantly is addressed, whereas creativity and especially task-commitment seem less represented. Our mapping demonstrates what a mathematics-specific specification of Renzulli’s theory can look like. Finally, we elaborate on the consequences of our findings, restrictions of our methodology, and on possible future research.
Kanive, Rebecca; Nelson, Peter M.; Burns, Matthew K.; Ysseldyke, James
2014-01-01
The authors' purpose was to determine the effects of computer-based practice and conceptual interventions on computational fluency and word-problem solving of fourth- and fifth-grade students with mathematics difficulties. A randomized pretest-posttest control group design found that students assigned to the computer-based practice intervention…
Lueking, Angela D; Wang, Cheng-Yu; Sircar, Sarmishtha; Malencia, Christopher; Wang, Hao; Li, Jing
2016-03-14
Flexible gate-opening metal organic frameworks (GO-MOFs) expand or contract to minimize the overall free energy of the system upon accommodation of an adsorbate. The thermodynamics of the GO process are well described by a number of models, but the kinetics of the process are relatively unexplored. A flexible GO-MOF, RPM3-Zn, exhibits a significant induction period for opening by N2 and Ar at low temperatures, both above and below the GO pressure. A similar induction period is not observed for H2 or O2 at comparable pressures and temperatures, suggesting the rate of opening is strongly influenced by the gas-surface interaction rather than an external stress. The induction period leads to severe mass transfer limitations for adsorption and over-prediction of the gate-opening pressure. After review of a number of existing adsorption rate models, we find that none adequately describe the experimental rate data and similar timescales for diffusion and opening invalidate prior reaction-diffusion models. Statistically, the rate data are best described by a compressed exponential function. The resulting fitted parameters exceed the expectations for adsorption but fall within those expected for phase transition. By treating adsorption as a phase transition, we generalize the Avrami theory of phase transition kinetics to describe adsorption in both rigid and flexible hosts. The generalized theory is consistent with observed experimental trends relating to induction period, temperature, pressure, and gas-substrate interaction.
2017-01-01
A large number of routing-related surveys are published so far for Wireless Sensor Networks (WSNs) that exhibit either complete or partial emphasis on routing in WSNs. These surveys classify and discuss the relevant routing protocols published mainly in the fields of classical, energy efficient, secure, hierarchical, geographic, intelligent, Quality of Service (QoS)-based and multipath WSNs. However, to the best of our knowledge, no study is presented so far which may clearly categorize the routing-related survey literature for WSNs.To fill this gap, an effort is made in this paper for presenting an in-depth review of already published routing-related survey literature in WSNs. Our review initially proposes a generalized survey design model and afterwards analyzes the routing-related survey literature in the light of the devised General Survey Design Framework (GSDF). Such an analysis describes the design soundness of the published routing-related surveys. Therefore, our review puts forth an original classification based on the frequency-of-survey-publication and taxonomizes the corresponding routing-related fields into high, medium and low focused areas of survey publication in WSNs. Furthermore, the surveys belonging to each main category are sub-categorized into various sub-classes and briefly discussed according to their design characteristics. On the one hand, this review is useful for beginners who may easily explore the already published routing-related survey literature in WSNs in a single document and investigate it by spending less effort. On the other hand, it is useful for expert researchers who may explore the trends and frequency of writing surveys in different areas of routing in WSNs. The experts may explore those areas of routing which are either neglected or least focused or lack in design soundness as per general survey design framework. In the end, insights and future research directions are outlined and a reasonable conclusion is put forth
Galbraith, Kevin; Ward, Alison; Heneghan, Carl
2017-05-03
Evidence-Based Medicine (EBM) skills have been included in general practice curricula and competency frameworks. However, GPs experience numerous barriers to developing and maintaining EBM skills, and some GPs feel the EBM movement misunderstands, and threatens their traditional role. We therefore need a new approach that acknowledges the constraints encountered in real-world general practice. The aim of this study was to synthesise from empirical research a real-world EBM competency framework for general practice, which could be applied in training, in the individual pursuit of continuing professional development, and in routine care. We sought to integrate evidence from the literature with evidence derived from the opinions of experts in the fields of general practice and EBM. We synthesised two sets of themes describing the meaning of EBM in general practice. One set of themes was derived from a mixed-methods systematic review of the literature; the other set was derived from the further development of those themes using a Delphi process among a panel of EBM and general practice experts. From these two sets of themes we constructed a real-world EBM competency framework for general practice. A simple competency framework was constructed, that acknowledges the constraints of real-world general practice: (1) mindfulness - in one's approach towards EBM itself, and to the influences on decision-making; (2) pragmatism - in one's approach to finding and evaluating evidence; and (3) knowledge of the patient - as the most useful resource in effective communication of evidence. We present a clinical scenario to illustrate how a GP might demonstrate these competencies in their routine daily work. We have proposed a real-world EBM competency framework for general practice, derived from empirical research, which acknowledges the constraints encountered in modern general practice. Further validation of these competencies is required, both as an educational resource and as a
Hadlock, Charles R
2013-01-01
The movement of groundwater in underground aquifers is an ideal physical example of many important themes in mathematical modeling, ranging from general principles (like Occam's Razor) to specific techniques (such as geometry, linear equations, and the calculus). This article gives a self-contained introduction to groundwater modeling with…
Haneuse, Sebastien; Daniels, Michael
2016-01-01
Electronic health records (EHR) data are increasingly seen as a resource for cost-effective comparative effectiveness research (CER). Since EHR data are collected primarily for clinical and/or billing purposes, their use for CER requires consideration of numerous methodologic challenges including the potential for confounding bias, due to a lack of randomization, and for selection bias, due to missing data. In contrast to the recent literature on confounding bias in EHR-based CER, virtually no attention has been paid to selection bias possibly due to the belief that standard methods for missing data can be readily-applied. Such methods, however, hinge on an overly simplistic view of the available/missing EHR data, so that their application in the EHR setting will often fail to completely control selection bias. Motivated by challenges we face in an on-going EHR-based comparative effectiveness study of choice of antidepressant treatment and long-term weight change, we propose a new general framework for selection bias in EHR-based CER. Crucially, the framework provides structure within which researchers can consider the complex interplay between numerous decisions, made by patients and health care providers, which give rise to health-related information being recorded in the EHR system, as well as the wide variability across EHR systems themselves. This, in turn, provides structure within which: (i) the transparency of assumptions regarding missing data can be enhanced, (ii) factors relevant to each decision can be elicited, and (iii) statistical methods can be better aligned with the complexity of the data. PMID:27668265
Hao, Zengchao; Hao, Fanghua; Singh, Vijay P.
2016-08-01
Drought is among the costliest natural hazards worldwide and extreme drought events in recent years have caused huge losses to various sectors. Drought prediction is therefore critically important for providing early warning information to aid decision making to cope with drought. Due to the complicated nature of drought, it has been recognized that the univariate drought indicator may not be sufficient for drought characterization and hence multivariate drought indices have been developed for drought monitoring. Alongside the substantial effort in drought monitoring with multivariate drought indices, it is of equal importance to develop a drought prediction method with multivariate drought indices to integrate drought information from various sources. This study proposes a general framework for multivariate multi-index drought prediction that is capable of integrating complementary prediction skills from multiple drought indices. The Multivariate Ensemble Streamflow Prediction (MESP) is employed to sample from historical records for obtaining statistical prediction of multiple variables, which is then used as inputs to achieve multivariate prediction. The framework is illustrated with a linearly combined drought index (LDI), which is a commonly used multivariate drought index, based on climate division data in California and New York in the United States with different seasonality of precipitation. The predictive skill of LDI (represented with persistence) is assessed by comparison with the univariate drought index and results show that the LDI prediction skill is less affected by seasonality than the meteorological drought prediction based on SPI. Prediction results from the case study show that the proposed multivariate drought prediction outperforms the persistence prediction, implying a satisfactory performance of multivariate drought prediction. The proposed method would be useful for drought prediction to integrate drought information from various sources
Mathematical Formulation of Multi-Layer Networks
De Domenico, Manlio; Cozzo, Emanuele; Kivelä, Mikko; Moreno, Yamir; Porter, Mason A; Gòmez, Sergio; Arenas, Alex
2013-01-01
A network representation is useful for describing the structure of a large variety of complex systems. However, most real and engineered systems have multiple subsystems and layers of connectivity, and the data produced by such systems is very rich. Achieving a deep understanding of such systems necessitates generalizing "traditional" network theory, and the newfound deluge of data now makes it possible to test increasingly general frameworks for the study of networks. In particular, although adjacency matrices are useful to describe traditional single-layer networks, such a representation is insufficient for the analysis and description of multiplex and time-dependent networks. One must therefore develop a more general mathematical framework to cope with the challenges posed by multi-layer complex systems. In this paper, we introduce a tensorial framework to study multi-layer networks, and we discuss the generalization of several important network descriptors and dynamical processes ---including degree centr...
Understanding mathematical proof
Taylor, John
2014-01-01
Introduction The need for proof The language of mathematics Reasoning Deductive reasoning and truth Example proofs Logic and ReasoningIntroduction Propositions, connectives, and truth tables Logical equivalence and logical implication Predicates and quantification Logical reasoning Sets and Functions Introduction Sets and membership Operations on setsThe Cartesian product Functions and composite functions Properties of functions The Structure of Mathematical ProofsIntroduction Some proofs dissected An informal framework for proofs Direct proof A more formal framework Finding Proofs Direct proo
Garrett, T. J.
2012-12-01
For any identifiable system, regardless of its complexity or scale, evolution can be treated as a spontaneous thermodynamic response to a local convergence of down-gradient material flows. In climate studies, examples of identifiable systems might include cloud cover or the global incidence of temperatures warmer than a certain threshold. Here it is shown how the time-dependent evolution of such systems is constrained by positive and negative feedbacks that fall into a few mathematically distinct modes. In general, evolution depends on the time integral of past flows and the current availability of material and energetic resources. More specifically, negative feedbacks arise from the depletion or predation of the material and potential energy reservoirs that supply the system. Positive feedbacks are due to either new reservoir "discovery" or system expansion into existing reservoirs. When positive feedbacks dominate, the time dependent response of system growth falls into a few clearly identifiable behaviors that include a law of diminishing returns, logistic behavior, and, if reservoirs are expanding very rapidly, unstable super-exponential or explosive growth. For open systems (e.g. radiative flows in our atmosphere) that have a resolved sink as well as a source, oscillatory behavior emerges and can be characterized in terms of a slightly modified form of the predator-prey equations commonly employed in ecology. The perturbation formulation of these equations is equivalent to a damped simple harmonic oscillator. Specific examples of non-equilibrium positive and negative feedback response can be described for the sudden development of rain and the oscillatory evolution of open-celled stratocumulus cloud decks.
Galligan, Linda
2016-01-01
A "National Numeracy Report" and the Australian Curriculum (2014) have recognised the importance of language in mathematics. The general capabilities contained within the "Australian Curriculum: Mathematics" (2014) highlight literacy as an important tool in the teaching and learning of mathematics, from the interpretation of…
Galligan, Linda
2016-01-01
A "National Numeracy Report" and the Australian Curriculum (2014) have recognised the importance of language in mathematics. The general capabilities contained within the "Australian Curriculum: Mathematics" (2014) highlight literacy as an important tool in the teaching and learning of mathematics, from the interpretation of…
Huang, Ding-jiang; Ivanova, Nataliya M.
2016-02-01
In this paper, we explain in more details the modern treatment of the problem of group classification of (systems of) partial differential equations (PDEs) from the algorithmic point of view. More precisely, we revise the classical Lie algorithm of construction of symmetries of differential equations, describe the group classification algorithm and discuss the process of reduction of (systems of) PDEs to (systems of) equations with smaller number of independent variables in order to construct invariant solutions. The group classification algorithm and reduction process are illustrated by the example of the generalized Zakharov-Kuznetsov (GZK) equations of form ut +(F (u)) xxx +(G (u)) xyy +(H (u)) x = 0. As a result, a complete group classification of the GZK equations is performed and a number of new interesting nonlinear invariant models which have non-trivial invariance algebras are obtained. Lie symmetry reductions and exact solutions for two important invariant models, i.e., the classical and modified Zakharov-Kuznetsov equations, are constructed. The algorithmic framework for group analysis of differential equations presented in this paper can also be applied to other nonlinear PDEs.
Directory of Open Access Journals (Sweden)
Fatima Sbeity
2013-01-01
Full Text Available Sub- and ultraharmonics generation by ultrasound contrast agents makes possible sub- and ultraharmonics imaging to enhance the contrast of ultrasound images and overcome the limitations of harmonic imaging. In order to separate different frequency components of ultrasound contrast agents signals, nonlinear models like single-input single-output (SISO Volterra model are used. One important limitation of this model is its incapacity to model sub- and ultraharmonic components. Many attempts are made to model sub- and ultraharmonics using Volterra model. It led to the design of mutiple-input singe-output (MISO Volterra model instead of SISO Volterra model. The key idea of MISO modeling was to decompose the input signal of the nonlinear system into periodic subsignals at the subharmonic frequency. In this paper, sub- and ultraharmonics modeling with MISO Volterra model is presented in a general framework that details and explains the required conditions to optimally model sub- and ultraharmonics. A new decomposition of the input signal in periodic orthogonal basis functions is presented. Results of application of different MISO Volterra methods to model simulated ultrasound contrast agents signals show its efficiency in sub- and ultraharmonics imaging.
Visscher, Peter M; Goddard, Michael E
2015-01-01
Heritability is a population parameter of importance in evolution, plant and animal breeding, and human medical genetics. It can be estimated using pedigree designs and, more recently, using relationships estimated from markers. We derive the sampling variance of the estimate of heritability for a wide range of experimental designs, assuming that estimation is by maximum likelihood and that the resemblance between relatives is solely due to additive genetic variation. We show that well-known results for balanced designs are special cases of a more general unified framework. For pedigree designs, the sampling variance is inversely proportional to the variance of relationship in the pedigree and it is proportional to 1/N, whereas for population samples it is approximately proportional to 1/N(2), where N is the sample size. Variation in relatedness is a key parameter in the quantification of the sampling variance of heritability. Consequently, the sampling variance is high for populations with large recent effective population size (e.g., humans) because this causes low variation in relationship. However, even using human population samples, low sampling variance is possible with high N. Copyright © 2015 by the Genetics Society of America.
Maximilien Brice
2007-01-01
National Science Foundation Assistant Director for Mathematics and Physical Sciences Tony Chan (USA) visiting LHCb experiment on 23rd May 2007 with Spokesperson T. Nakada, Advisor to CERN Director-General J. Ellis and I. Belyaev of Syracuse
Hiriart-Urruty, Jean-Baptiste
2016-01-01
This book contains a collection of exercises (called “tapas”) at undergraduate level, mainly from the fields of real analysis, calculus, matrices, convexity, and optimization. Most of the problems presented here are non-standard and some require broad knowledge of different mathematical subjects in order to be solved. The author provides some hints and (partial) answers and also puts these carefully chosen exercises into context, presents information on their origins, and comments on possible extensions. With stars marking the levels of difficulty, these tapas show or prove something interesting, challenge the reader to solve and learn, and may have surprising results. This first volume of Mathematical Tapas will appeal to mathematicians, motivated undergraduate students from science-based areas, and those generally interested in mathematics.
Cahill, Kevin
2013-01-01
Unique in its clarity, examples and range, Physical Mathematics explains as simply as possible the mathematics that graduate students and professional physicists need in their courses and research. The author illustrates the mathematics with numerous physical examples drawn from contemporary research. In addition to basic subjects such as linear algebra, Fourier analysis, complex variables, differential equations and Bessel functions, this textbook covers topics such as the singular-value decomposition, Lie algebras, the tensors and forms of general relativity, the central limit theorem and Kolmogorov test of statistics, the Monte Carlo methods of experimental and theoretical physics, the renormalization group of condensed-matter physics and the functional derivatives and Feynman path integrals of quantum field theory.
Odille, Fabrice G J; Jónsson, Stefán; Stjernqvist, Susann; Rydén, Tobias; Wärnmark, Kenneth
2007-01-01
A general mathematical model for the characterization of the dynamic (kinetically labile) association of supramolecular assemblies in solution is presented. It is an extension of the equal K (EK) model by the stringent use of linear algebra to allow for the simultaneous presence of an unlimited number of different units in the resulting assemblies. It allows for the analysis of highly complex dynamic equilibrium systems in solution, including both supramolecular homo- and copolymers without the recourse to extensive approximations, in a field in which other analytical methods are difficult. The derived mathematical methodology makes it possible to analyze dynamic systems such as supramolecular copolymers regarding for instance the degree of polymerization, the distribution of a given monomer in different copolymers as well as its position in an aggregate. It is to date the only general means to characterize weak supramolecular systems. The model was fitted to NMR dilution titration data by using the program Matlab, and a detailed algorithm for the optimization of the different parameters has been developed. The methodology is applied to a case study, a hydrogen-bonded supramolecular system, salen 4+porphyrin 5. The system is formally a two-component system but in reality a three-component system. This results in a complex dynamic system in which all monomers are associated to each other by hydrogen bonding with different association constants, resulting in homo- and copolymers 4n5m as well as cyclic structures 6 and 7, in addition to free 4 and 5. The system was analyzed by extensive NMR dilution titrations at variable temperatures. All chemical shifts observed at different temperatures were used in the fitting to obtain the DeltaH degrees and DeltaS degrees values producing the best global fit. From the derived general mathematical expressions, system 4+5 could be characterized with respect to above-mentioned parameters.
Jost, Jürgen
2015-01-01
The main intention of this book is to describe and develop the conceptual, structural and abstract thinking of mathematics. Specific mathematical structures are used to illustrate the conceptual approach; providing a deeper insight into mutual relationships and abstract common features. These ideas are carefully motivated, explained and illustrated by examples so that many of the more technical proofs can be omitted. The book can therefore be used: · simply as an overview of the panorama of mathematical structures and the relations between them, to be supplemented by more detailed texts whenever you want to acquire a working knowledge of some structure · by itself as a first introduction to abstract mathematics · together with existing textbooks, to put their results into a more general perspective · to gain a new and hopefully deeper perspective after having studied such textbooks Mathematical Concepts has a broader scope and is less detaile...
Murphy, Kerry; O'Connor, Denise A; Browning, Colette J; French, Simon D; Michie, Susan; Francis, Jill J; Russell, Grant M; Workman, Barbara; Flicker, Leon; Eccles, Martin P; Green, Sally E
2014-03-03
Dementia is a growing problem, causing substantial burden for patients, their families, and society. General practitioners (GPs) play an important role in diagnosing and managing dementia; however, there are gaps between recommended and current practice. The aim of this study was to explore GPs' reported practice in diagnosing and managing dementia and to describe, in theoretical terms, the proposed explanations for practice that was and was not consistent with evidence-based guidelines. Semi-structured interviews were conducted with GPs in Victoria, Australia. The Theoretical Domains Framework (TDF) guided data collection and analysis. Interviews explored the factors hindering and enabling achievement of 13 recommended behaviours. Data were analysed using content and thematic analysis. This paper presents an in-depth description of the factors influencing two behaviours, assessing co-morbid depression using a validated tool, and conducting a formal cognitive assessment using a validated scale. A total of 30 GPs were interviewed. Most GPs reported that they did not assess for co-morbid depression using a validated tool as per recommended guidance. Barriers included the belief that depression can be adequately assessed using general clinical indicators and that validated tools provide little additional information (theoretical domain of 'Beliefs about consequences'); discomfort in using validated tools ('Emotion'), possibly due to limited training and confidence ('Skills'; 'Beliefs about capabilities'); limited awareness of the need for, and forgetting to conduct, a depression assessment ('Knowledge'; 'Memory, attention and decision processes'). Most reported practising in a manner consistent with the recommendation that a formal cognitive assessment using a validated scale be undertaken. Key factors enabling this were having an awareness of the need to conduct a cognitive assessment ('Knowledge'); possessing the necessary skills and confidence ('Skills'; 'Beliefs
Ellerton, Nerida F.
2013-01-01
Although official curriculum documents make cursory mention of the need for problem posing in school mathematics, problem posing rarely becomes part of the implemented or assessed curriculum. This paper provides examples of how problem posing can be made an integral part of mathematics teacher education programs. It is argued that such programs…
Direct and indirect influences of executive functions on mathematics achievement.
Cragg, Lucy; Keeble, Sarah; Richardson, Sophie; Roome, Hannah E; Gilmore, Camilla
2017-02-08
Achievement in mathematics is predicted by an individual's domain-specific factual knowledge, procedural skill and conceptual understanding as well as domain-general executive function skills. In this study we investigated the extent to which executive function skills contribute to these three components of mathematical knowledge, whether this mediates the relationship between executive functions and overall mathematics achievement, and if these relationships change with age. Two hundred and ninety-three participants aged between 8 and 25years completed a large battery of mathematics and executive function tests. Domain-specific skills partially mediated the relationship between executive functions and mathematics achievement: Inhibitory control within the numerical domain was associated with factual knowledge and procedural skill, which in turn was associated with mathematical achievement. Working memory contributed to mathematics achievement indirectly through factual knowledge, procedural skill and, to a lesser extent, conceptual understanding. There remained a substantial direct pathway between working memory and mathematics achievement however, which may reflect the role of working memory in identifying and constructing problem representations. These relationships were remarkably stable from 8years through to young adulthood. Our findings help to refine existing multi-component frameworks of mathematics and understand the mechanisms by which executive functions support mathematics achievement.
Heldeweg, Michiel A.; Sanders, Maurits
2014-01-01
This article provides a framework to guide the choice and design of a fitting Public Private Partnerships (PPP), which is applied to a Dutch example of biogas/sustainable energy projects. The framework focuses on ‘legitimate public governance’, merging Beetham’s dimensions of legitimacy (legality,
Chen, Haiwen
2012-01-01
In this article, linear item response theory (IRT) observed-score equating is compared under a generalized kernel equating framework with Levine observed-score equating for nonequivalent groups with anchor test design. Interestingly, these two equating methods are closely related despite being based on different methodologies. Specifically, when…
Directory of Open Access Journals (Sweden)
Lian eDuan
2015-07-01
Full Text Available Studying the neural basis of human social interactions is a key topic in the field of social neuroscience. Brain imaging studies in this field usually focus on the neural correlates of the social interactions between two participants. However, as the participant number further increases, even by a small amount, great difficulties raise. One challenge is how to concurrently scan all the interacting brains with high ecological validity, especially for a large number of participants. The other challenge is how to effectively model the complex group interaction behaviors emerging from the intricate neural information exchange among a group of socially organized people. Confronting these challenges, we propose a new approach called Cluster Imaging of Multi-brain Networks (CIMBN. CIMBN consists of two parts. The first part is a cluster imaging technique with high ecological validity based on multiple functional near-infrared spectroscopy (fNIRS systems. Using this technique, we can easily extend the simultaneous imaging capacity of social neuroscience studies up to dozens of participants. The second part of CIMBN is a multi-brain network (MBN modeling method based on graph theory. By taking each brain as a network node and the relationship between any two brains as a network edge, one can construct a network model for a group of interacting brains. The emergent group social behaviors can then be studied using the network’s properties, such as its topological structure and information exchange efficiency. Although there is still much work to do, as a general framework for hyperscanning and modeling a group of interacting brains, CIMBN can provide new insights into the neural correlates of group social interactions, and advance social neuroscience and social psychology.
Andersen, A H; Gash, D M; Avison, M J
1999-07-01
Principal component analysis (PCA) is one of several structure-seeking multivariate statistical techniques, exploratory as well as inferential, that have been proposed recently for the characterization and detection of activation in both PET and fMRI time series data. In particular, PCA is data driven and does not assume that the neural or hemodynamic response reaches some steady state, nor does it involve correlation with any pre-defined or exogenous experimental design template. In this paper, we present a generalized linear systems framework for PCA based on the singular value decomposition (SVD) model for representation of spatio-temporal fMRI data sets. Statistical inference procedures for PCA, including point and interval estimation will be introduced without the constraint of explicit hypotheses about specific task-dependent effects. The principal eigenvectors capture both the spatial and temporal aspects of fMRI data in a progressive fashion; they are inherently matched to unique and uncorrelated features and are ranked in order of the amount of variance explained. PCA also acts as a variation reduction technique, relegating most of the random noise to the trailing components while collecting systematic structure into the leading ones. Features summarizing variability may not directly be those that are the most useful. Further analysis is facilitated through linear subspace methods involving PC rotation and strategies of projection pursuit utilizing a reduced, lower-dimensional natural basis representation that retains most of the information. These properties will be illustrated in the setting of dynamic time-series response data from fMRI experiments involving pharmacological stimulation of the dopaminergic nigro-striatal system in primates.
Plofker, Kim
2009-01-01
Based on extensive research in Sanskrit sources, Mathematics in India chronicles the development of mathematical techniques and texts in South Asia from antiquity to the early modern period. Kim Plofker reexamines the few facts about Indian mathematics that have become common knowledge--such as the Indian origin of Arabic numerals--and she sets them in a larger textual and cultural framework. The book details aspects of the subject that have been largely passed over in the past, including the relationships between Indian mathematics and astronomy, and their cross-fertilizations with Islamic sc
Teacher's Guide to Secondary Mathematics.
Duval County Schools, Jacksonville, FL.
This is a teacher's guide to secondary school mathematics. Developed for use in the Duval County Public Schools, Jacksonville, Florida. Areas of mathematics covered are algebra, analysis, calculus, computer literacy, computer science, geometry, analytic geometry, general mathematics, consumer mathematics, pre-algebra, probability and statistics,…
A Mathematics Software Database Update.
Cunningham, R. S.; Smith, David A.
1987-01-01
Contains an update of an earlier listing of software for mathematics instruction at the college level. Topics are: advanced mathematics, algebra, calculus, differential equations, discrete mathematics, equation solving, general mathematics, geometry, linear and matrix algebra, logic, statistics and probability, and trigonometry. (PK)
DEFF Research Database (Denmark)
Westphael, Henning; Mogensen, Arne
2013-01-01
In this article we present the notion of Mathematical competences as a tool to describe the mathematically gifted students.......In this article we present the notion of Mathematical competences as a tool to describe the mathematically gifted students....
Academic literacy in mathematics for English Learners
Moschkovich, JN
2015-01-01
© 2015 Elsevier Inc. This paper uses a sociocultural conceptual framework to provide an integrated view of academic literacy in mathematics for English Learners. The proposed definition of academic literacy in mathematics includes three integrated components: mathematical proficiency, mathematical practices, and mathematical discourse. The paper uses an analysis of a classroom discussion to illustrate how the three components of academic literacy in mathematics are intertwined, how academic l...
Mathematical Texts as Narrative: Rethinking Curriculum
Dietiker, Leslie
2013-01-01
This paper proposes a framework for reading mathematics texts as narratives. Building from a narrative framework of Meike Bal, a reader's experience with the mathematical content as it unfolds in the text (the "mathematical story") is distinguished from his or her logical reconstruction of the content beyond the text (the…
Mathematics for physical chemistry
Mortimer, Robert G
2013-01-01
Mathematics for Physical Chemistry is the ideal supplementary text for practicing chemists and students who want to sharpen their mathematics skills while enrolled in general through physical chemistry courses. This book specifically emphasizes the use of mathematics in the context of physical chemistry, as opposed to being simply a mathematics text. This 4e includes new exercises in each chapter that provide practice in a technique immediately after discussion or example and encourage self-study. The early chapters are constructed around a sequence of mathematical topics, wit
Directory of Open Access Journals (Sweden)
Claudio F. M. Toledo
2015-01-01
Full Text Available This paper presents the synchronized and integrated two-level lot sizing and scheduling problem (SITLSP. This problem is found in beverage production, foundry, glass industry, and electrofused grains, where the production processes have usually two interdependent levels with sequence-dependent setups in each level. For instance, in the first level of soft drink production, raw materials are stored in tanks flowing to production lines in the second level. The amount and the time the raw materials and products have to be stored and produced should be determined. A synchronization problem occurs because the production in lines and the storage in tanks have to be compatible with each other throughout the time horizon. The SITLSP and its mathematical model are described in detail by this paper. The lack of similar models in the literature has led us to also propose a set of instances for the SITLSP, based on data provided by a soft drink company. Thus, a set of benchmark results for these problem instances are established using an exact method available in an optimization package. Moreover, results for two relaxations proved that the modeling methodology could be useful in real-world applications.
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
This paper explains and summarizes a new attempt to derive a general mathematical model [GMM] to simulate surface acoustic wave (SAW) filters, using the superposition principle and delta function model. GMM can be used to simulate One-to-One, One-to-Multi and Multi-to-Multi SAW filter devices. The simulation program was written using MATLAB (the language of technical computing). Four-design structures (One-to-One, One-to-Two, One-to-Three and Ten-to-Ten) ware selected to test the correctness of GMM. The frequency response of the simulation and test results are similar in center frequency and 3-dB bandwidth, but the insertion loss is different, because of some second order effects (Issa Haitham, 1999).
Shi, Ye; Zhou, Xingyi; Zhang, Jun; Bruck, Andrea M; Bond, Andrew C; Marschilok, Amy C; Takeuchi, Kenneth J; Takeuchi, Esther S; Yu, Guihua
2017-03-08
Controlling architecture of electrode composites is of particular importance to optimize both electronic and ionic conduction within the entire electrode and improve the dispersion of active particles, thus achieving the best energy delivery from a battery. Electrodes based on conventional binder systems that consist of carbon additives and nonconductive binder polymers suffer from aggregation of particles and poor physical connections, leading to decreased effective electronic and ionic conductivities. Here we developed a three-dimensional (3D) nanostructured hybrid inorganic-gel framework electrode by in situ polymerization of conductive polymer gel onto commercial lithium iron phosphate particles. This framework electrode exhibits greatly improved rate and cyclic performance because the highly conductive and hierarchically porous network of the hybrid gel framework promotes both electronic and ionic transport. In addition, both inorganic and organic components are uniformly distributed within the electrode because the polymer coating prevents active particles from aggregation, enabling full access to each particle. The robust framework further provides mechanical strength to support active electrode materials and improves the long-term electrochemical stability. The multifunctional conductive gel framework can be generalized for other high-capacity inorganic electrode materials to enable high-performance lithium ion batteries.
Bárcenas, R. B.; Hernández, H. H. H.; Sabido, M.
2015-11-01
The collection of papers in this volume was presented during the X Mexican School on Gravitation and Mathematical Physics, which was held in Playa del Carmen, Quintana Roo, México, December 1-5, 2014. The Mexican School on Gravitation and Mathematical Physics is a series of conferences sponsored by the Mexican Physical Society that started in 1994 with the purposes of discussing and exchanging current ideas in gravitational physics. Each Mexican School has been devoted to a particular subject, and these have included supergravity, branes, black holes, the early Universe, observational cosmology, quantum gravity and numerical relativity. In this ocasion the theme of the school was Reaching a Century: Classical and Modified General Relativity's Attempts to explain the evolution of the Universe, which focused on the discussion of classical and modified aspects of general relativity. Following our previous Schools, world leaders in the field were invited to give courses and plenary lectures. More specialized talks were also presented in parallel sessions, and some of them have been included in these proceedings. The contributions in this volume have been reviewed and represent some of the courses, plenary talks and contributed talks presented during our X School. We are indebted to the contributors of these proceedings as well as to the rest of the participants in our Mexican School all for making of it a complete success. As for financial support we should mention the Mexican National Science and Technology Council (CONACyT), the Royal Society of London (UK), the Mexican Physical Society (SMF), as well as several Institutions including: Centro de Investigación y Estudios Avanzados (CINVESTAV), Universidad Autónoma Metropolitana Iztapalapa (UAM-I), Universidad de Guanajuato (UG), and Universidad Nacional Autónoma de México (UNAM).
Kupryaev, N. V.
2016-07-01
The precession of the perihelion of Mercury's orbit for 100 years in the gravitational field of the Sun and the planets has been numerically modeled within the framework of a generalized law of universal gravitation with refined data on the parameters of the orbits of the planets (including the asteroid belt and Pluto), and also the gravitational constant and with a smaller iteration step (0.0002 s). The calculations were performed with enhanced computational accuracy. It has been shown that the average precession of Mercury's orbit in 100 years within the framework of the generalized law of universal gravitation comprises ~565.3''. This is less than the observed shift of the perihelion by about 8.8''. The observed shift of the perihelion, as is well known, comprises ~574.1''. It is not ruled out that inside Mercury's orbit some unknown undetected object (or several such objects) of small size remains to be found.
General logarithmic image processing convolution.
Palomares, Jose M; González, Jesús; Ros, Eduardo; Prieto, Alberto
2006-11-01
The logarithmic image processing model (LIP) is a robust mathematical framework, which, among other benefits, behaves invariantly to illumination changes. This paper presents, for the first time, two general formulations of the 2-D convolution of separable kernels under the LIP paradigm. Although both formulations are mathematically equivalent, one of them has been designed avoiding the operations which are computationally expensive in current computers. Therefore, this fast LIP convolution method allows to obtain significant speedups and is more adequate for real-time processing. In order to support these statements, some experimental results are shown in Section V.
Ratio Analysis: Where Investments Meet Mathematics.
Barton, Susan D.; Woodbury, Denise
2002-01-01
Discusses ratio analysis by which investments may be evaluated. Requires the use of fundamental mathematics, problem solving, and a comparison of the mathematical results within the framework of industry. (Author/NB)
Generalizing the Minkowski metric
Chappell, James M; Abbott, Derek
2015-01-01
The mathematical framework developed by Minkowski in 1909 successfully explained the new ideas about space and time, developed by Einstein in the special theory of relativity, directly from the geometrical properties of a four-dimensional spacetime continuum. However, while Einstein's theory was firmly based on two physical postulates, the mathematical structure of Minkowski was not so well founded and subsequently there have been many attempts to provide a more fundamental derivation. In this paper we aim to provide such a derivation based on the elementary geometrical properties of three-dimensional space modeled using the algebraic structure of Clifford multivectors. We find that Clifford multivectors produce a generalization of Minkowski's formulation thus placing the results of special relativity in a larger setting. This then leads to a generalization of several results including Noether's theorem.
General flat four-dimensional world pictures and clock systems
Hsu, J. P.; Underwood, J. A.
1978-01-01
We explore the mathematical structure and the physical implications of a general four-dimensional symmetry framework which is consistent with the Poincare-Einstein principle of relativity for physical laws and with experiments. In particular, we discuss a four-dimensional framework in which all observers in different frames use one and the same grid of clocks. The general framework includes special relativity and a recently proposed new four-dimensional symmetry with a nonuniversal light speed as two special simple cases. The connection between the properties of light propagation and the convention concerning clock systems is also discussed, and is seen to be nonunique within the four-dimensional framework.
Luther, Kenneth H.
2012-01-01
Mathematical modeling of groundwater flow is a topic at the intersection of mathematics and geohydrology and is rarely encountered in undergraduate mathematics. However, this subject is full of interesting and meaningful examples of truly "applied" mathematics accessible to undergraduates, from the pre-calculus to advanced mathematics levels. This…
Luther, Kenneth H.
2012-01-01
Mathematical modeling of groundwater flow is a topic at the intersection of mathematics and geohydrology and is rarely encountered in undergraduate mathematics. However, this subject is full of interesting and meaningful examples of truly "applied" mathematics accessible to undergraduates, from the pre-calculus to advanced mathematics levels. This…
Metz, Mary Louise
2010-01-01
Statistics education has become an increasingly important component of the mathematics education of today's citizens. In part to address the call for a more statistically literate citizenship, The "Guidelines for Assessment and Instruction in Statistics Education (GAISE)" were developed in 2005 by the American Statistical Association. These…
Communicational Perspectives on Learning and Teaching Mathematics: Prologue
Tabach, Michal; Nachlieli, Talli
2016-01-01
This special issue comprises five studies which vary in their focus and mathematical content, yet they all share an underlying communicational theoretical framework--commognition. Within this framework, learning mathematics is defined as a change in one's mathematical discourse, that is, in the form of communication known as mathematical. Teaching…
Chen, Bor-Sen; Lin, Ying-Po
2013-01-01
Robust stabilization and environmental disturbance attenuation are ubiquitous systematic properties that are observed in biological systems at many different levels. The underlying principles for robust stabilization and environmental disturbance attenuation are universal to both complex biological systems and sophisticated engineering systems. In many biological networks, network robustness should be large enough to confer: intrinsic robustness for tolerating intrinsic parameter fluctuations; genetic robustness for buffering genetic variations; and environmental robustness for resisting environmental disturbances. Network robustness is needed so phenotype stability of biological network can be maintained, guaranteeing phenotype robustness. Synthetic biology is foreseen to have important applications in biotechnology and medicine; it is expected to contribute significantly to a better understanding of functioning of complex biological systems. This paper presents a unifying mathematical framework for investigating the principles of both robust stabilization and environmental disturbance attenuation for synthetic gene networks in synthetic biology. Further, from the unifying mathematical framework, we found that the phenotype robustness criterion for synthetic gene networks is the following: if intrinsic robustness + genetic robustness + environmental robustness ≦ network robustness, then the phenotype robustness can be maintained in spite of intrinsic parameter fluctuations, genetic variations, and environmental disturbances. Therefore, the trade-offs between intrinsic robustness, genetic robustness, environmental robustness, and network robustness in synthetic biology can also be investigated through corresponding phenotype robustness criteria from the systematic point of view. Finally, a robust synthetic design that involves network evolution algorithms with desired behavior under intrinsic parameter fluctuations, genetic variations, and environmental
A generalized biharmonic equation and its applications to hydrodynamic instability
Indian Academy of Sciences (India)
Mihir B Banerjee; J R Gupta; R G Shandil
2002-06-01
Problems concerning characterization of eigenvalues of some linear and homogenous differential systems by the Pellew and Southwell method of conjugate eigenfunctions in the domain of hydrodynamic instability are discussed and a general mathematical framework described. In this general survey we look back on and rewrite this work almost in exactly the way it evolved out of a few naive looking calculations in hydrodynamic instability. We show in the process the close relationship that exists between mathematical analysis and its applications with due credit to intuition as the main source of mathematical activity.
The Impact of the Interaction between Verbal and Mathematical ...
African Journals Online (AJOL)
A.K.K. Odhiambo and S.O. Gunga
mathematical language and verbal language, and that the teaching of mathematics ... Learning mathematics results in more than a mastery of basic skills: .... crossing cultural and language barriers.… in general, a mathematics equation.
Directory of Open Access Journals (Sweden)
Lutsenko Y. V.
2014-01-01
Full Text Available This article briefly reviews the classical concept of functional dependence in mathematics, determines the limitations of this concept for adequate modeling of reality and formulates the problem, consisting in search of such generalization of the concept of func-tions, which is more suitable for the adequate reflec-tion of causal relationships in the real domain. Also, it discusses theoretical and practical solving the prob-lem, consisting in: (a we suggest the universal method of calculating the amount of information in the value of argument about the meaning of the function, i.e. cognitive functions which is independent from the subject area; b we offer software tools: Eidos intelli-gent system, allowing in practice to carry out these calculations, i.e. to build cognitive functions based on a fragmented noisy empirical data of high dimension. We also offer the concepts of nonreducing, partially and completely reduced direct and inverse, positive and negative cognitive functions and the method of formation of reduced cognitive function, which is a generalization of known weighted least-squares meth-od on the basis of observation the amount of infor-mation in the values of the argument about the values of the functions accounting
Developing Mathematical Vocabulary.
Monroe, Eula Ewing; Orme, Michelle P.
2002-01-01
This article discusses the importance of mathematical vocabulary, difficulties students encounter in learning this vocabulary, and some instructional strategies. Two general methods for teaching vocabulary are discussed: context and explicit vocabulary instruction. The methods are summarized as they apply to mathematical vocabulary instruction and…
Dyslexia, Dyspraxia and Mathematics.
Yeo, Dorian
This book explores how primary school children with dyslexia or dyspraxia and difficulty in math can learn math and provides practical support and detailed teaching suggestions. It considers cognitive features that underlie difficulty with mathematics generally or with specific aspects of mathematics. It outlines the ways in which children usually…
How Mathematical Knowledge for Teaching May Profit from the Study of History of Mathematics
Mosvold, Reidar; Jakobsen, Arne; Jankvist, Uffe Thomas
2014-01-01
In this theoretical article, we aim at theorizing the old statement that mathematics teachers might profit from studying the history of mathematics. We do this by drawing upon the theoretical framework of mathematical knowledge for teaching (MKT). A selection of international studies on the history and pedagogy of mathematics is used as starting…
Mekkaoui, Imen; Moulin, Kevin; Croisille, Pierre; Pousin, Jerome; Viallon, Magalie
2016-08-01
Cardiac motion presents a major challenge in diffusion weighted MRI, often leading to large signal losses that necessitate repeated measurements. The diffusion process in the myocardium is difficult to investigate because of the unqualified sensitivity of diffusion measurements to cardiac motion. A rigorous mathematical formalism is introduced to quantify the effect of tissue motion in diffusion imaging. The presented mathematical model, based on the Bloch-Torrey equations, takes into account deformations according to the laws of continuum mechanics. Approximating this mathematical model by using finite elements method, numerical simulations can predict the sensitivity of the diffusion signal to cardiac motion. Different diffusion encoding schemes are considered and the diffusion weighted MR signals, computed numerically, are compared to available results in literature. Our numerical model can identify the existence of two time points in the cardiac cycle, at which the diffusion is unaffected by myocardial strain and cardiac motion. Of course, these time points depend on the type of diffusion encoding scheme. Our numerical results also show that the motion sensitivity of the diffusion sequence can be reduced by using either spin echo technique with acceleration motion compensation diffusion gradients or stimulated echo acquisition mode with unipolar and bipolar diffusion gradients.
Obstacle problems in mathematical physics
Rodrigues, J-F
1987-01-01
The aim of this research monograph is to present a general account of the applicability of elliptic variational inequalities to the important class of free boundary problems of obstacle type from a unifying point of view of classical Mathematical Physics.The first part of the volume introduces some obstacle type problems which can be reduced to variational inequalities. Part II presents some of the main aspects of the theory of elliptic variational inequalities, from the abstract hilbertian framework to the smoothness of the variational solution, discussing in general the properties of the free boundary and including some results on the obstacle Plateau problem. The last part examines the application to free boundary problems, namely the lubrication-cavitation problem, the elastoplastic problem, the Signorini (or the boundary obstacle) problem, the dam problem, the continuous casting problem, the electrochemical machining problem and the problem of the flow with wake in a channel past a profile.
Bouchaud, Jean-Philippe; Sornette, Didier
1994-06-01
The ability to price risks and devise optimal investment strategies in thé présence of an uncertain "random" market is thé cornerstone of modern finance theory. We first consider thé simplest such problem of a so-called "European call option" initially solved by Black and Scholes using Ito stochastic calculus for markets modelled by a log-Brownien stochastic process. A simple and powerful formalism is presented which allows us to generalize thé analysis to a large class of stochastic processes, such as ARCH, jump or Lévy processes. We also address thé case of correlated Gaussian processes, which is shown to be a good description of three différent market indices (MATIF, CAC40, FTSE100). Our main result is thé introduction of thé concept of an optimal strategy in the sense of (functional) minimization of the risk with respect to the portfolio. If the risk may be made to vanish for particular continuous uncorrelated 'quasiGaussian' stochastic processes (including Black and Scholes model), this is no longer the case for more general stochastic processes. The value of the residual risk is obtained and suggests the concept of risk-corrected option prices. In the presence of very large deviations such as in Lévy processes, new criteria for rational fixing of the option prices are discussed. We also apply our method to other types of options, `Asian', `American', and discuss new possibilities (`doubledecker'...). The inclusion of transaction costs leads to the appearance of a natural characteristic trading time scale. L'aptitude à quantifier le coût du risque et à définir une stratégie optimale de gestion de portefeuille dans un marché aléatoire constitue la base de la théorie moderne de la finance. Nous considérons d'abord le problème le plus simple de ce type, à savoir celui de l'option d'achat `européenne', qui a été résolu par Black et Scholes à l'aide du calcul stochastique d'Ito appliqué aux marchés modélisés par un processus Log
Directory of Open Access Journals (Sweden)
Rebecca Prebble
2005-09-01
Full Text Available This paper considers whether Croatia would benefit from the introduction of a general anti-avoidance rule into its tax system. The paper gives an overview of what tax avoidance is and differentiates the concept from the related concepts of tax evasion and fraud. The paper then describes how general anti-avoidance rules work. The paper gives an overview of Croatia’s tax system, including the measures the country already has to combat tax avoidance, and concludes that a general anti-avoidance rule is necessary. The paper draws on the experiences of countries with legal systems similar to that of Croatia to suggest the form that a Croatian general anti-avoidance rule should take.
Mathematical Footprints Discovering Mathematics Everywhere
Pappas, Theoni
1999-01-01
MATHEMATICAL FOOTPRINTS takes a creative look at the role mathematics has played since prehistoric times, and will play in the future, and uncovers mathematics where you least expect to find it from its many uses in medicine, the sciences, and its appearance in art to its patterns in nature and its central role in the development of computers. Pappas presents mathematical ideas in a readable non-threatening manner. MATHEMATICAL FOOTPRINTS is another gem by the creator of THE MATHEMATICS CALENDAR and author of THE JOY OF MATHEMATICS. "Pappas's books have been gold mines of mathematical ent
Peuquet, Donna J.
1987-01-01
A new approach to building geographic data models that is based on the fundamental characteristics of the data is presented. An overall theoretical framework for representing geographic data is proposed. An example of utilizing this framework in a Geographic Information System (GIS) context by combining artificial intelligence techniques with recent developments in spatial data processing techniques is given. Elements of data representation discussed include hierarchical structure, separation of locational and conceptual views, and the ability to store knowledge at variable levels of completeness and precision.
Mathematical Sciences Institute Workshop
Scott, Philip
1990-01-01
A so-called "effective" algorithm may require arbitrarily large finite amounts of time and space resources, and hence may not be practical in the real world. A "feasible" algorithm is one which only requires a limited amount of space and/or time for execution; the general idea is that a feasible algorithm is one which may be practical on today's or at least tomorrow's computers. There is no definitive analogue of Church's thesis giving a mathematical definition of feasibility; however, the most widely studied mathematical model of feasible computability is polynomial-time computability. Feasible Mathematics includes both the study of feasible computation from a mathematical and logical point of view and the reworking of traditional mathematics from the point of view of feasible computation. The diversity of Feasible Mathematics is illustrated by the. contents of this volume which includes papers on weak fragments of arithmetic, on higher type functionals, on bounded linear logic, on sub recursive definitions ...
Johnson, E. A.; Ball, T. C.
2014-12-01
An important objective in general education geoscience courses is to help students evaluate social and ethical issues based upon scientific knowledge. It can be difficult for instructors trained in the physical sciences to design effective ways of including ethical issues in large lecture courses where whole-class discussions are not practical. The Quality Enhancement Plan for James Madison University, "The Madison Collaborative: Ethical Reasoning in Action," (http://www.jmu.edu/mc/index.shtml) has identified eight key questions to be used as a framework for developing ethical reasoning exercises and evaluating student learning. These eight questions are represented by the acronym FOR CLEAR and are represented by the concepts of Fairness, Outcomes, Responsibilities, Character, Liberty, Empathy, Authority, and Rights. In this study, we use the eight key questions as an inquiry-based framework for addressing ethical issues in a 100-student general education Earth systems and climate change course. Ethical reasoning exercises are presented throughout the course and range from questions of personal behavior to issues regarding potential future generations and global natural resources. In the first few exercises, key questions are identified for the students and calibrated responses are provided as examples. By the end of the semester, students are expected to identify key questions themselves and justify their own ethical and scientific reasoning. Evaluation rubrics are customized to this scaffolding approach to the exercises. Student feedback and course data will be presented to encourage discussion of this and other approaches to explicitly incorporating ethical reasoning in general education geoscience courses.
Liu, Chang; Wu, Yi-Nan; Morlay, Catherine; Gu, Yifan; Gebremariam, Binyam; Yuan, Xiao; Li, Fengting
2016-02-01
Electrospun nanofibrous mats are ideal substrates for metal-organic frameworks (MOFs) crystal deposition because of their specific structural parameters and chemical tenability. In this work, we utilized organic-inorganic hybrid electrospun fibrous mats as support material to study the deposition of various MOF particles. HKUST-1 and MIL-53(Al) were produced through solvothermal method, while ZIF-8 and MIL-88B(Fe) were prepared using microwave-induced heating method. The synthesis procedure for both methods were simple and effective because the hybrid nanofibrous mats showed considerable affinity to MOF particles and could be used without additional modifications. The obtained MOF composites exhibited effective incorporation between MOF particles and the porous substrates. MIL-53(Al) composite was applied as fibrous sorbent and showed enhanced adsorption capacity and removal rate, as well as easier operation, compared with thepowdered sample. Moreover, MIL-53(Al) composite was easier to be regenerated compared with powder form.
López, Gabriel A.; Sáenz, Jon; Leonardo, Aritz; Gurtubay, Idoia G.
2016-01-01
The "Moodle" platform has been used to put into practice an ongoing evaluation of the students' Physics learning process. The evaluation has been done on the frame of the course General Physics, which is lectured during the first year of the Physics, Mathematics and Electronic Engineering Programmes at the Faculty of Science and…
St. John, Michael M.; Babo, Gerard
2015-01-01
This study examined the influence of placement in a co-taught inclusive classroom on the academic achievement of general education students in grades 6-8 in a suburban New York school district on the 2014 New York State ELA and Mathematics Assessments. Propensity Score Matching (PSM) was utilized for sample selection in order to simulate a more…
López, Gabriel A.; Sáenz, Jon; Leonardo, Aritz; Gurtubay, Idoia G.
2016-01-01
The "Moodle" platform has been used to put into practice an ongoing evaluation of the students' Physics learning process. The evaluation has been done on the frame of the course General Physics, which is lectured during the first year of the Physics, Mathematics and Electronic Engineering Programmes at the Faculty of Science and…
Bansal, Manjit K
2004-01-01
Discusses the rationale of applying relationship marketing and service quality concepts within the primary health care sector. The use of relational strategies in general practice, by modelling the relationships between practitioners and patients from a marketing perspective, could potentially lead to sustained high quality service being provided, and to more efficient use of resources. This essentially conceptually focused paper addresses an area that has not yet been researched in detail, and furthers understanding of the relationships that facilitate exchange within general practice and service delivery in non-profit, resource-constrained conditions. Deeper understanding of the needs and expectations of patients and the way these can be delivered by general practice can only lead to improvements for all parties involved. The relationship marketing paradigm presents itself as a potentially exciting way of addressing issues associated with ensuring that the highest level of quality is delivered in this area of the UK National Health Service.
Energy Technology Data Exchange (ETDEWEB)
Brewer, Jeffrey D.
2005-11-01
The objective of this report is to promote increased understanding of decision making processes and hopefully to enable improved decision making regarding high-consequence, highly sophisticated technological systems. This report brings together insights regarding risk perception and decision making across domains ranging from nuclear power technology safety, cognitive psychology, economics, science education, public policy, and neural science (to name a few). It forms them into a unique, coherent, concise framework, and list of strategies to aid in decision making. It is suggested that all decision makers, whether ordinary citizens, academics, or political leaders, ought to cultivate their abilities to separate the wheat from the chaff in these types of decision making instances. The wheat includes proper data sources and helpful human decision making heuristics; these should be sought. The chaff includes ''unhelpful biases'' that hinder proper interpretation of available data and lead people unwittingly toward inappropriate decision making ''strategies''; obviously, these should be avoided. It is further proposed that successfully accomplishing the wheat vs. chaff separation is very difficult, yet tenable. This report hopes to expose and facilitate navigation away from decision-making traps which often ensnare the unwary. Furthermore, it is emphasized that one's personal decision making biases can be examined, and tools can be provided allowing better means to generate, evaluate, and select among decision options. Many examples in this report are tailored to the energy domain (esp. nuclear power for electricity generation). The decision making framework and approach presented here are applicable to any high-consequence, highly sophisticated technological system.
Nimmo, J.R.; Herkelrath, W.N.; Laguna, Luna A.M.
2007-01-01
Numerous models are in widespread use for the estimation of soil water retention from more easily measured textural data. Improved models are needed for better prediction and wider applicability. We developed a basic framework from which new and existing models can be derived to facilitate improvements. Starting from the assumption that every particle has a characteristic dimension R associated uniquely with a matric pressure ?? and that the form of the ??-R relation is the defining characteristic of each model, this framework leads to particular models by specification of geometric relationships between pores and particles. Typical assumptions are that particles are spheres, pores are cylinders with volume equal to the associated particle volume times the void ratio, and that the capillary inverse proportionality between radius and matric pressure is valid. Examples include fixed-pore-shape and fixed-pore-length models. We also developed alternative versions of the model of Arya and Paris that eliminate its interval-size dependence and other problems. The alternative models are calculable by direct application of algebraic formulas rather than manipulation of data tables and intermediate results, and they easily combine with other models (e.g., incorporating structural effects) that are formulated on a continuous basis. Additionally, we developed a family of models based on the same pore geometry as the widely used unsaturated hydraulic conductivity model of Mualem. Predictions of measurements for different suitable media show that some of the models provide consistently good results and can be chosen based on ease of calculations and other factors. ?? Soil Science Society of America. All rights reserved.
ELPSA as a Lesson Design Framework
Lowrie, Tom; Patahuddin, Sitti Maesuri
2015-01-01
This paper offers a framework for a mathematics lesson design that is consistent with the way we learn about, and discover, most things in life. In addition, the framework provides a structure for identifying how mathematical concepts and understanding are acquired and developed. This framework is called ELPSA and represents five learning…
Vanbinst, Kiran; Ghesquière, Pol; De Smedt, Bert
2014-11-01
Deficits in arithmetic fact retrieval constitute the hallmark of children with mathematical learning difficulties (MLD). It remains, however, unclear which cognitive deficits underpin these difficulties in arithmetic fact retrieval. Many prior studies defined MLD by considering low achievement criteria and not by additionally taking the persistence of the MLD into account. Therefore, the present longitudinal study contrasted children with persistent MLD (MLD-p; mean age: 9 years 2 months) and typically developing (TD) children (mean age: 9 years 6 months) at three time points, to explore whether differences in arithmetic strategy development were associated with differences in numerical magnitude processing, working memory and phonological processing. Our longitudinal data revealed that children with MLD-p had persistent arithmetic fact retrieval deficits at each time point. Children with MLD-p showed persistent impairments in symbolic, but not in nonsymbolic, magnitude processing at each time point. The two groups differed in phonological processing, but not in working memory. Our data indicate that both domain-specific and domain-general cognitive abilities contribute to individual differences in children's arithmetic strategy development, and that the symbolic processing of numerical magnitudes might be a particular risk factor for children with MLD-p.
A novel control framework for internet based tele-robotics
Institute of Scientific and Technical Information of China (English)
WANG Yong-ming; XIAO Nan-feng; YIN Hong-li; JIANG Yan-rong; DUAN Peng
2008-01-01
Aiming at the tele-operation instability caused by time delay of internet information transfer for internet based tele-robotics,tbis paper proposes a novel control framework for internet based tele-robotics,which can guarantee the non-distortion-transfer of control information and reduce the difference of action time between the local simulated virtual robot and the remote real robot.This framework is insensitive to the inherent internet time delay,and diffelrs from other tele-roboties systems that try to use some mathematic models to deseribe the internet delay or take some assumptions.In order to verify the framework.a 4-DOF fisehertechnik industry robot tele-operation system has been developed using the Hew proposed framework.Experimental results demonstrate the applicable performance of the new framework.The framework is open structured and Call be applied to other general purposed tele-operation systems.
General and Maladaptive Traits in a Five-Factor Framework for "DSM"-5 in a University Student Sample
De Fruyt, Filip; De Clercq, Barbara; De Bolle, Marleen; Wille, Bart; Markon, Kristian; Krueger, Robert F.
2013-01-01
The relationships between two measures proposed to describe personality pathology, that is the Revised NEO Personality Inventory (NEO-PI-3) and the Personality Inventory for "DSM"-5 (PID-5), are examined in an undergraduate sample (N = 240). The NEO inventories are general trait measures, also considered relevant to assess disordered…
General and Maladaptive Traits in a Five-Factor Framework for "DSM"-5 in a University Student Sample
De Fruyt, Filip; De Clercq, Barbara; De Bolle, Marleen; Wille, Bart; Markon, Kristian; Krueger, Robert F.
2013-01-01
The relationships between two measures proposed to describe personality pathology, that is the Revised NEO Personality Inventory (NEO-PI-3) and the Personality Inventory for "DSM"-5 (PID-5), are examined in an undergraduate sample (N = 240). The NEO inventories are general trait measures, also considered relevant to assess disordered…
Elements of mathematics general topology
Bourbaki, Nicolas
1995-01-01
This is the softcover reprint of the English translation of 1971 (available from Springer since 1989) of the first 4 chapters of Bourbaki's Topologie générale. It gives all the basics of the subject, starting from definitions. Important classes of topological spaces are studied, uniform structures are introduced and applied to topological groups. Real numbers are constructed and their properties established. Part II, comprising the later chapters, Ch. 5-10, is also available in English in softcover.
Energy Technology Data Exchange (ETDEWEB)
Busch, P. [Berufsschule Lueneburg (Germany)
1995-12-31
This book wants to help readers understand what happens in control systems without excessively complex mathematics. It addresses a broad range of readers, for instance, pupils and students at vocational grammar schools, technical schools and colleges. In addition, it is suited for continuing education - thanks to its numerous examples and exercises with solutions - and for self-study. As the practical side should not be neglected, each general consideration is followed by the calculation of a practical example. Furthermore, exercises with solutions are offered for self-control. Upon finishing the book, the reader should be able to analyze a controlled system according to automatic control criteria and to select and set a suitable controller. For complex controlled systems, the exact mathematical calculation would be too comprehensive. For such cases it is common in practice to make use of experimentally obtained approximations, which are equally described. The book has not only been thoroughly revised; a new chapter on fuzzy logic and its use in automatic control has been added (orig./GL) [Deutsch] Anliegen dieses Buches ist es, dem Leser die Zusammenhaenge in Regelkreisen verstaendlich zu machen, ohne dass die mathematischen Betrachtungen zu kompliziert werden. Angesprochen werden soll damit ein breiter Leserkreis, z.B. Schueler und Studierende an beruflichen Gymnasien, Fachschulen (Technikerschulen), Fachhochschulen. Das Buch ist aber auch geeignet fuer entsprechende Fortbildungsveranstaltungen sowie - dank der zahlreichen Beispiele und Uebungsaufgaben mit Loesungen - zum Selbststudium. Damit der praktische Aspekt nicht zu kurz kommt, wird nach jeder allgemeinen Betrachtung ein konkretes Beispiel berechnet. Zur Selbstkontrolle werden zusaetzlich Uebungsaufgaben mit Loesungen angeboten. Der Leser soll nach Studium des Buches in der Lage sein, eine Regelstrecke nach regelungstechnischen Kritieren zu analysieren und einen dafuer passenden Reglertyp auszuwaehlen und
Institute of Scientific and Technical Information of China (English)
王飞跃
2006-01-01
This is a brief review on the recent book: Duality System in Applied Mechanics and Optimal Control, by Zhong Wan-Xie, published by Kluwer Academic Publishers, 2004. The book represents a significant effort to re-establish the historic and deep tie between control and mechanics by striving to connect and integrate concepts, methods, and algorithms in mechanics and control so that a unified framework can be established for both analytical and computational purposes.Clearly, it has demonstrated that the duality system method can be used as a mathematical and systematic foundation to deal with many important concepts and problems in both mechanics and control. This book is not only very useful for research and applications, but also extremely helpful for multidisciplinary curriculum development when students from one field are trying to learning and applying concepts and methods from the other field.
Slavkin, H C
2001-01-01
The Surgeon General's Report, Oral Health in America, is the first comprehensive assessment of oral, dental, and craniofacial health in the history of our nation. The intent of this first-ever Report is to alert Americans to the full meaning of oral health and its importance to general health and well-being across the lifespan. Moreover, the Report has been released at a time in human history of enormous changes as well as opportunities. The convergence of public health policies, "quality of life" expectations, global informatics, a new century of biotechnology, the completion of the Human Genome Project, changes in the management of health care, and the acknowledgment of enormous health disparities herald a call to action. These profound dynamics particularly affect children and their caregivers and the multitude of social, economic, and health issues associated with special patients and developmental disabilities. This paper will highlight the issues, provide recommendations, and suggest a call to action.
Directory of Open Access Journals (Sweden)
Aristophanes Dimakis
2011-12-01
Full Text Available The non-autonomous chiral model equation for an m×m matrix function on a two-dimensional space appears in particular in general relativity, where for m=2 a certain reduction of it determines stationary, axially symmetric solutions of Einstein's vacuum equations, and for m=3 solutions of the Einstein-Maxwell equations. Using a very simple and general result of the bidifferential calculus approach to integrable partial differential and difference equations, we generate a large class of exact solutions of this chiral model. The solutions are parametrized by a set of matrices, the size of which can be arbitrarily large. The matrices are subject to a Sylvester equation that has to be solved and generically admits a unique solution. By imposing the aforementioned reductions on the matrix data, we recover the Ernst potentials of multi-Kerr-NUT and multi-Deminski-Newman metrics.
Beneke, M.; Hellmann, C.; Ruiz-Femenia, P.
2012-01-01
We compute analytically the tree-level annihilation rates of a collection of non-relativistic neutralino and chargino two-particle states in the general MSSM, including the previously unknown off-diagonal rates. The results are prerequisites to the calculation of the Sommerfeld enhancement in the MSSM, which will be presented in subsequent work. They can also be used to obtain concise analytic expressions for MSSM dark matter pair annihilation in the present Universe for a large number of exc...