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.
Mathematical aspects of logic programming semantics
Hitzler, Pascal
2010-01-01
Covering the authors' own state-of-the-art research results, Mathematical Aspects of Logic Programming Semantics presents a rigorous, modern account of the mathematical methods and tools required for the semantic analysis of logic programs. It significantly extends the tools and methods from traditional order theory to include nonconventional methods from mathematical analysis that depend on topology, domain theory, generalized distance functions, and associated fixed-point theory.The book covers topics spanning the period from the early days of logic programming to current times. It discusses
Aspects of Mathematical Morphology
Michielsen, K.; Raedt, H. De; Hosson, J.Th.M. De
2002-01-01
In this paper we review the basic concepts of integral-geometry-based morphological image analysis. This approach yields an objective, numerical characterization of two- and three-dimensional patterns in terms of geometrical and topological descriptors called Minkowski functionals. We review its mat
Mathematical aspects of natural dynamos
Dormy, Emmanuel
2007-01-01
Although the origin of Earth's and other celestial bodies' magnetic fields remains unknown, we do know that the motion of electrically conducting fluids generates and maintains these fields, forming the basis of magnetohydrodynamics (MHD) and, to a larger extent, dynamo theory. Answering the need for a comprehensive, interdisciplinary introduction to this area, ""Mathematical Aspects of Natural Dynamos"" provides a foundation in dynamo theory before moving on to modeling aspects of natural dynamos.Bringing together eminent international contributors, the book first introduces governing equatio
Mathematical aspects of infectious disease dynamics
Boldin, B.
2007-01-01
The thesis `Mathematical aspects of infectious disease dynamics' by Barbara Boldin is about model formulation, analysis and interpretation of four questions arising from biology or medicine. Suppose that a new population is introduced into a steady community. When the basic reproduction ratio R_0 of
Aspects of Children's Mathematics Anxiety.
Newstead, Karen
1998-01-01
Focuses on mathematics anxiety in 9- to 11-year-old children. Compares the mathematics anxiety of pupils taught in a traditional manner with that of pupils whose teachers adopted an alternative teaching approach that emphasizes problem solving and discussion of the pupil's own informal strategies. Concludes that pupils exposed to the traditional…
Mathematical aspects of scattering amplitudes
Duhr, Claude
2014-01-01
In these lectures we discuss some of the mathematical structures that appear when computing multi-loop Feynman integrals. We focus on a specific class of special functions, the so-called multiple polylogarithms, and discuss introduce their Hopf algebra structure. We show how these mathematical concepts are useful in physics by illustrating on several examples how these algebraic structures are useful to perform analytic computations of loop integrals, in particular to derive functional equations among polylogarithms.
Mathematical aspects of scattering amplitudes
Duhr, Claude
2014-01-01
In these lectures we discuss some of the mathematical structures that appear when computing multi-loop Feynman integrals. We focus on a specific class of special functions, the so-called multiple polylogarithms, and discuss introduce their Hopf algebra structure. We show how these mathematical concepts are useful in physics by illustrating on several examples how these algebraic structures are useful to perform analytic computations of loop integrals, in particular to derive functional equati...
Mathematical Aspects of Scattering Amplitudes
Duhr, Claude
In these lectures we discuss some of the mathematical structures that appear when computing multi-loop Feynman integrals. We focus on a specific class of special functions, the so-called multiple polylogarithms, and introduce their Hopf algebra structure. We show how these mathematical concepts are useful in physics by illustrating on several examples how these algebraic structures are useful to perform analytic computations of loop integrals, in particular to derive functional equations among polylogarithms.
Mathematical aspects of Feynman integrals
Energy Technology Data Exchange (ETDEWEB)
Bogner, Christian
2009-08-15
In the present dissertation we consider Feynman integrals in the framework of dimensional regularization. As all such integrals can be expressed in terms of scalar integrals, we focus on this latter kind of integrals in their Feynman parametric representation and study their mathematical properties, partially applying graph theory, algebraic geometry and number theory. The three main topics are the graph theoretic properties of the Symanzik polynomials, the termination of the sector decomposition algorithm of Binoth and Heinrich and the arithmetic nature of the Laurent coefficients of Feynman integrals. The integrand of an arbitrary dimensionally regularised, scalar Feynman integral can be expressed in terms of the two well-known Symanzik polynomials. We give a detailed review on the graph theoretic properties of these polynomials. Due to the matrix-tree-theorem the first of these polynomials can be constructed from the determinant of a minor of the generic Laplacian matrix of a graph. By use of a generalization of this theorem, the all-minors-matrix-tree theorem, we derive a new relation which furthermore relates the second Symanzik polynomial to the Laplacian matrix of a graph. Starting from the Feynman parametric parameterization, the sector decomposition algorithm of Binoth and Heinrich serves for the numerical evaluation of the Laurent coefficients of an arbitrary Feynman integral in the Euclidean momentum region. This widely used algorithm contains an iterated step, consisting of an appropriate decomposition of the domain of integration and the deformation of the resulting pieces. This procedure leads to a disentanglement of the overlapping singularities of the integral. By giving a counter-example we exhibit the problem, that this iterative step of the algorithm does not terminate for every possible case. We solve this problem by presenting an appropriate extension of the algorithm, which is guaranteed to terminate. This is achieved by mapping the iterative
Mathematical aspects of degressive proportionality
Slomczynski, Wojciech
2011-01-01
We analyze properties of apportionment functions in context of the problem of allocating seats in the European Parliament. Necessary and sufficient conditions for apportionment functions are investigated. Some exemplary families of apportionment functions are specified and the corresponding partitions of the seats in the European Parliament among the Member States of the European Union are presented. Although the choice of the allocation functions is theoretically unlimited, we show that the constraints are so strong that the acceptable functions lead to rather similar solutions.
Mathematical aspects of quantum field theories
Strobl, Thomas
2015-01-01
Despite its long history and stunning experimental successes, the mathematical foundation of perturbative quantum field theory is still a subject of ongoing research. This book aims at presenting some of the most recent advances in the field, and at reflecting the diversity of approaches and tools invented and currently employed. Both leading experts and comparative newcomers to the field present their latest findings, helping readers to gain a better understanding of not only quantum but also classical field theories. Though the book offers a valuable resource for mathematicians and physicists alike, the focus is more on mathematical developments. This volume consists of four parts: The first Part covers local aspects of perturbative quantum field theory, with an emphasis on the axiomatization of the algebra behind the operator product expansion. The second Part highlights Chern-Simons gauge theories, while the third examines (semi-)classical field theories. In closing, Part 4 addresses factorization homolo...
Mathematical Aspects of Network Routing Optimization
Oliveira, Carlos AS
2011-01-01
Before the appearance of broadband links and wireless systems, networks have been used to connect people in new ways. Now, the modern world is connected through large-scale, computational networked systems such as the Internet. Because of the ever-advancing technology of networking, efficient algorithms have become increasingly necessary to solve some of the problems developing in this area. "Mathematical Aspects of Network Routing Optimization" focuses on computational issues arising from the process of optimizing network routes, such as quality of the resulting links and their reli
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.
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 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.
Mathematical aspects of reacting and diffusing systems
Fife, Paul C
1979-01-01
Modeling and analyzing the dynamics of chemical mixtures by means of differ- tial equations is one of the prime concerns of chemical engineering theorists. These equations often take the form of systems of nonlinear parabolic partial d- ferential equations, or reaction-diffusion equations, when there is diffusion of chemical substances involved. A good overview of this endeavor can be had by re- ing the two volumes by R. Aris (1975), who himself was one of the main contributors to the theory. Enthusiasm for the models developed has been shared by parts of the mathematical community, and these models have, in fact, provided motivation for some beautiful mathematical results. There are analogies between chemical reactors and certain biological systems. One such analogy is rather obvious: a single living organism is a dynamic structure built of molecules and ions, many of which react and diffuse. Other analogies are less obvious; for example, the electric potential of a membrane can diffuse like a chemical, and ...
Some Aspects of Mathematics and Computer Science in Japan,
Japan. In fact, he learned about a rather wide variety of research in various aspects of applied mathematics and computer science . The readers...Mathematics . Those interested in computer science and applications software will be most interested in the work at Fujitsu Limited and the work at the
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.
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…
Aspects of generalized Calogero model
Meljanac, S; Milekovic, M
2004-01-01
A multispecies model of Calogero type in $D\\geq 1$ dimensions is constructed. The model includes harmonic, two-body and three-body interactions. Using the underlying conformal SU(1,1) algebra, we find the exact eigenenergies corresponding to a class of the exact global collective states. Analysing corresponding Fock space, we detect the universal critical point at which the model exhibits singular behaviour.
General aspects of optical vortices
CSIR Research Space (South Africa)
Roux, FS
2009-01-01
Full Text Available . Stef Roux CSIR National Laser Centre PO Box 395, Pretoria 0001, South Africa CSIR National Laser Centre – p.1/32 Contents . Definition of an optical vortex . Topological charge and vortex morphology . How to detect a vortex — interferometry . How... to generate optical vortices CSIR National Laser Centre – p.2/32 Persistent dark spots Optical vortices CSIR National Laser Centre – p.3/32 Speckle field Amplitude Phase CSIR National Laser Centre – p.4/32 Singular phase function CSIR National Laser Centre – p...
Foundations of mathematical analysis
Johnsonbaugh, Richard
2010-01-01
This classroom-tested volume offers a definitive look at modern analysis, with views of applications to statistics, numerical analysis, Fourier series, differential equations, mathematical analysis, and functional analysis. Upper-level undergraduate students with a background in calculus will benefit from its teachings, along with beginning graduate students seeking a firm grounding in modern analysis. A self-contained text, it presents the necessary background on the limit concept, and the first seven chapters could constitute a one-semester introduction to limits. Subsequent chapters discuss
On Mathematical Aspects of Dual Variables in Continuum Mechanics. Part 1 : Mathematical Principles
Giessen, E. van der; Kollmann, F.G.
1996-01-01
In this paper consisting of two parts we consider mathematical aspects of dual variables appearing in continuum mechanics. Tensor calculus on manifolds as introduced into continuum mechanics is used as a point of departure. This mathematical formalism leads to additional structure of continuum
On Mathematical Aspects of Dual Variables in Continuum Mechanics. Part 1 : Mathematical Principles
Giessen, E. van der; Kollmann, F.G.
1996-01-01
In this paper consisting of two parts we consider mathematical aspects of dual variables appearing in continuum mechanics. Tensor calculus on manifolds as introduced into continuum mechanics is used as a point of departure. This mathematical formalism leads to additional structure of continuum mecha
Some aspects of modern population mathematics.
Brillinger, D R
1981-01-01
"The purpose of this paper is to survey a number of the technical tools and models that have found use in the study of human and other populations, and to indicate some problems of current interest. These tools and models are varied: integral equations, nonlinear oscillations, differential geometry, dynamical systems, nonlinear operation, bifurcation theory, semigroup theory, martingale theory, Markov processes, diffusion processes, branching processes, ergodic theory, prediction theory and state-space models. A fairly extensive bibliography is provided. Also an Appendix has been added describing the analysis of a classical entomological data set." (summary in FRE)
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.
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.
Making mathematics and science integration happen: key aspects of practice
Ríordáin, Máire Ní; Johnston, Jennifer; Walshe, Gráinne
2016-02-01
The integration of mathematics and science teaching and learning facilitates student learning, engagement, motivation, problem-solving, criticality and real-life application. However, the actual implementation of an integrative approach to the teaching and learning of both subjects at classroom level, with in-service teachers working collaboratively, at second-level education, is under-researched due to the complexities of school-based research. This study reports on a year-long case study on the implementation of an integrated unit of learning on distance, speed and time, within three second-level schools in Ireland. This study employed a qualitative approach and examined the key aspects of practice that impact on the integration of mathematics and science teaching and learning. We argue that teacher perspective, teacher knowledge of the 'other subject' and of technological pedagogical content knowledge (TPACK), and teacher collaboration and support all impact on the implementation of an integrative approach to mathematics and science education.
The fundamentals of mathematical analysis
Fikhtengol'ts, G M
1965-01-01
The Fundamentals of Mathematical Analysis, Volume 1 is a textbook that provides a systematic and rigorous treatment of the fundamentals of mathematical analysis. Emphasis is placed on the concept of limit which plays a principal role in mathematical analysis. Examples of the application of mathematical analysis to geometry, mechanics, physics, and engineering are given. This volume is comprised of 14 chapters and begins with a discussion on real numbers, their properties and applications, and arithmetical operations over real numbers. The reader is then introduced to the concept of function, i
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)
It's about time elementary mathematical aspects of relativity
Cooke, Roger
2017-01-01
This book has three main goals. First, it explores a selection of topics from the early period of the theory of relativity, focusing on particular aspects that are interesting or unusual. These include the twin paradox relativistic mechanics and its interaction with Maxwell's laws the earliest triumphs of general relativity relating to the orbit of Mercury and the deflection of light passing near the sun and the surprising bizarre metric of Kurt Godel, in which time travel is possible. Second, it provides an exposition of the differential geometry needed to understand these topics on a level that is intended to be accessible to those with just two years of university-level mathematics as background. Third, it reflects on the historical development of the subject and its significance for our understanding of what reality is and how we can know about the physical universe. The book also takes note of historical prefigurations of relativity, such as Euler's 1744 result that a particle moving on a surface and sub...
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...
Some Aspects of Individual Differences in Mathematics Instruction.
Radatz, Hendrik
1979-01-01
The article includes a general discussion of individual differences and a report of a study conducted as a part of the Frankfurt Project. The study indicated that, in primary school, reflective pupils seem to be better achievers in mathematics than impulsive students. (MK)
Aspects of general higher-order gravities
Bueno, Pablo; Min, Vincent S; Visser, Manus R
2016-01-01
We study several aspects of higher-order gravities constructed from general contractions of the Riemann tensor and the metric in arbitrary dimensions. First, we use the fast-linearization procedure presented in arXiv:1607.06463 to obtain the equations satisfied by the metric perturbation modes on a maximally symmetric background in the presence of matter and to classify $\\mathcal{L}($Riemann$)$ theories according to their spectrum. Then, we linearize all theories up to quartic order in curvature and use this result to construct quartic versions of Einsteinian cubic gravity (ECG). In addition, we show that the most general cubic gravity constructed in a dimension-independent way and which does not propagate the ghost-like spin-2 mode (but can propagate the scalar) is a linear combination of $f($Lovelock$)$ invariants, plus the ECG term, plus a New ghost-free gravity term. Next, we construct the generalized Newton potential and the Post-Newtonian parameter $\\gamma$ for general $\\mathcal{L}($Riemann$)$ gravities...
General Aspects of the Economical Crisis
Directory of Open Access Journals (Sweden)
Gina Ioan
2011-02-01
Full Text Available According to the economic theories, crises does not follow a general model, each of them,presenting unique aspects, representing actually an accident, generated by specific factors, at a certainsocio-economic and political situation. Like a classification of the crisis we can specify: the crisis ofliquidity in the banking sector, external balance of payments crisis, currency crisis, external debtcrisis and the financial crisis. After we have analyze the causes of the major crisis in XIX-th and XXthcenturies, we broach the principal causes of the actual world crisis. The implications of the crisis inEst-Europe and in Romania are analyzed from the point of view of these economies vulnerability anda series of mistakes taken in the governance acts. The theory of State intervention in the adjustment ofeconomic mechanisms, due to J.M. Keynes, is bring like an argument for exceed the negative effectsof the crisis.
Institute of Scientific and Technical Information of China (English)
1996-01-01
A semiquanitative catheter culture for earlydetection of surgical wound infection was doneby rolling a segment of a plastic intravenouscatheter across a blood agar plate after insertioninto the most inflammed part of the wound onpostoperative day 3. Incisions were monitoreddaily for infection sign until healing of the 55wounds studied, 49 (89.1%) had no growth or
Institute of Scientific and Technical Information of China (English)
1996-01-01
960566 Acute nectrotic fasciitis in infancy.Zhang Shaojin (张绍锦), et al.Dept Surg,Qinghai Child Hosp, Xining 810007.Chin JPediatr Surg 1996; 17(4): 237-239 Thirty infants of acute necrotic fascitis wereadmitted. Three cases had a history of intra-muscular injection. The situs of 26 cases werein lumbodorsal and buttocks. The offending or-ganism was a mixed infection of staphylococ-cus aureus, streptococcus, colibacillus or an-acrobic bacillus (bactericides fragile). Thetreatment included early multiple incision and
Institute of Scientific and Technical Information of China (English)
1996-01-01
Because of progressive infectious necrosison right and forearm for 3 months and the ne-crosis on left mid-finger for 2 months, a girl pa-tient, Yang Xiaoxia was admitted on 15th, Nov.1994. Systemic intoxicative symptom wasslight and the necrotic tissue presented blackscar. After 3 months treatment by applicationot multiple antibiotics, local dressing changesand an amputation of right forearm, the necro-
Mathematical analysis of deception.
Energy Technology Data Exchange (ETDEWEB)
Rogers, Deanna Tamae Koike (University of California at Davis, Davis, CA); Durgin, Nancy Ann
2003-10-01
This report describes the results of a three year research project about the use of deception in information protection. The work involved a collaboration between Sandia employees and students in the Center for Cyber Defenders (CCD) and at the University of California at Davis. This report includes a review of the history of deception, a discussion of some cognitive issues, an overview of previous work in deception, the results of experiments on the effects of deception on an attacker, and a mathematical model of error types associated with deception in computer systems.
Topological aspects of generalized Harper operators
De Nittis, Giuseppe
2012-01-01
A generalized version of the TKNN-equations computing Hall conductances for generalized Dirac-like Harper operators is derived. Geometrically these equations relate Chern numbers of suitable (dual) bundles naturally associated to spectral projections of the operators.
Semiotic aspects of cognitive development: illustrations from early mathematical cognition.
Becker, J; Varelas, M
1993-07-01
The premise of this article is that cognitive development involves both conceptual and semiotic achievements. From this perspective, the authors emphasize the distinctness of the semiotic issues and develop a differentiated appreciation of semiotic aspects of cognition, particularly in the field of elementary mathematical cognition. The authors provide semiotic analyses of the differences between counting, adding, and multiplying and of the conventional place-value sign system. The authors introduce the concept of the field of reference of a sign, the differentiation of the field into foreground and background, and the dynamics within the field of reference. Finally, the authors relate these ideas to the dynamics between two dimensions of semiotic relations: the sign-referent dimension and the sign-sign dimension.
Directory of Open Access Journals (Sweden)
Y. A. Perminov
2014-01-01
Full Text Available The paper substantiates the need for profile training in mathematical modeling for pedagogical students, caused by the total penetration of mathematics into different sciences, including the humanities; fast development of the information communications technologies; and growing importance of mathematical modeling, combining the informal scientific and formal mathematical languages with the unique opportunities of computer programming. The author singles out the reasons for mastering and using the mathematical apparatus by teaches in every discipline. Indeed, among all the modern mathematical methods and ideas, mathematical modeling retains its priority in all professional spheres. Therefore, the discipline of “Mathematical Modeling” can play an important role in integrating different components of specialists training in various profiles. By mastering the basics of mathematical modeling, students acquire skills of methodological thinking; learn the principles of analysis, synthesis, generalization of ideas and methods in different disciplines and scientific spheres; and achieve general culture competences. In conclusion, the author recommends incorporating the “Methods of Profile Training in Mathematical Modeling” into the pedagogical magistracy curricula.
Directory of Open Access Journals (Sweden)
Abdias Laohombé
2014-01-01
Full Text Available A two-patch model, SEi1,…,EinIiLi, i=1,2, is used to analyze the spread of tuberculosis, with an arbitrary number n of latently infected compartments in each patch. A fraction of infectious individuals that begun their treatment will not return to the hospital for the examination of sputum. This fact usually occurs in sub-Saharan Africa, due to many reasons. The model incorporates migrations from one patch to another. The existence and uniqueness of the associated equilibria are discussed. A Lyapunov function is used to show that when the basic reproduction ratio is less than one, the disease-free equilibrium is globally and asymptotically stable. When it is greater than one, there exists at least one endemic equilibrium. The local stability of endemic equilibria can be illustrated using numerical simulations. Numerical simulation results are provided to illustrate the theoretical results and analyze the influence of lost sight individuals.
Discrete Mathematical Chemistry: Social Aspects of its Emergence and Reception
Directory of Open Access Journals (Sweden)
Guillermo Restrepo
2013-07-01
Full Text Available We first show some successes of discrete mathematical chemistry (DMC, a branch of theoretical chemistry born in the 1960s and 1970s. Then we explore the social context in which the emergence of DMC took place, initiated mainly in East European countries. The availability of knowledge, especially of mathematical knowledge, and the lack of research funds were the main conditions that helped get DMC started. We also explore the reception of DMC in the chemical and mathematical circles, being flat rejection in chemistry and slow acceptance in mathematics. Finally, we discuss some definitions of the subject and propose a new one stating that mathematical chemistry is the realization of mathematical thinking in chemistry, understood as functional thinking defined by Felix Klein in the Erlangen Program.
Mathematical aspects of pattern formation in biological systems
Wei, Juncheng
2013-01-01
This monograph is concerned with the mathematical analysis of patterns which are encountered in biological systems. It summarises, expands and relates results obtained in the field during the last fifteen years. It also links the results to biological applications and highlights their relevance to phenomena in nature. Of particular concern are large-amplitude patterns far from equilibrium in biologically relevant models.The approach adopted in the monograph is based on the following paradigms:â€¢ Examine the existence of spiky steady states in reaction-diffusion systems and select as observabl
Falsetti, Marcela; Alvarez, Marisa
2015-01-01
We present an analysis of students' formal constructions in mathematics regarding to syntactic, semantic and pragmatic aspects. The analyzed tasks correspond to students of the Course of Mathematics for the admission to the university. Our study was qualitative, consisted in the identification, analysis and interpretation, focused in logic…
Fundamentals of mathematical analysis
Paul J Sally, Jr
2013-01-01
This is a textbook for a course in Honors Analysis (for freshman/sophomore undergraduates) or Real Analysis (for junior/senior undergraduates) or Analysis-I (beginning graduates). It is intended for students who completed a course in "AP Calculus", possibly followed by a routine course in multivariable calculus and a computational course in linear algebra. There are three features that distinguish this book from many other books of a similar nature and which are important for the use of this book as a text. The first, and most important, feature is the collection of exercises. These are spread
Mathematical and numerical aspects of low mach number flows
Energy Technology Data Exchange (ETDEWEB)
Schochet, St.; Bresch, D.; Grenier, E.; Alazard, T.; Gordner, A.; Sankaran, V.; Massot, M.; Sery, R.; Pebay, P.; Lunch, O.; Mazhorova, O.; Turkel, O.E.; Faille, I.; Danchin, R.; Allain, O.; Birken, P.; Lafitte, O.; Kloczko, T.; Frick, W.; Bui, T.; Dellacherie, S.; Klein, R.; Roe, Ph.; Accary, G.; Braack, M.; Picano, F.; Cadiou, A.; Dinescu, C.; Lesage, A.C.; Wesseling, P.; Heuveline, V.; Jobelin, M.; Weisman, C.; Merkle, C.
2004-07-01
Low Mach number flows represent a significant part of the various flows encountered in geophysics, industry or every day life. Paradoxically, the mathematical analysis of the equations governing these flows is difficult and on the practical side, the research of numerical algorithms valid for all flow speeds is continuing to be a challenge. However, in the last decade, both from the theoretical and the numerical sides, significant progresses were made in the understanding and analysis of the equations governing these flows. This conference intends to provide an up-to-date inventory of recent mathematical and numerical results in the analysis of these flows by bringing together both mathematicians and numericists active in this area. In the framework of the conference, a numerical workshop is organized which proposes to compute several challenging low Mach number flows: liquid flow around non-cavitating and cavitating NACA0015 hydrofoil, natural convection with large temperature differences, free convection, free surface flow, vessel pressurization. This document brings together the descriptions of the test cases of the numerical workshop and the abstracts of the conference papers: A 3D high order finite volume method for the prediction of near-critical fluid flows (G. ACCARY, I. RASPO, P. BONTOUX, B. ZAPPOLI); low Mach number limit of the non-isentropic Navier-Stokes equations (T. ALAZARD); simulation of cavitation rolls past a forward step with a bubble model (O. ALLAIN, N. BLASKA, C. LECA); flux preconditioning methods and fire events (P. BIRKEN, A. MEISTER); an adaptive finite element solver for compressible flows: application to heat-driven cavity benchmarks in 2D and 3D (M. BRAACK); comparison of various implicit, explicit, centered and upwind schemes for the simulation of compressed flows on moving mesh (A. CADIOU, M. BUFFAT, L. Le PENVEN, C. Le RIBAULT); low Mach number limit for viscous compressible flows (R. DANCHIN); some Properties of the low Mach number
Mathematical and numerical aspects of low mach number flows
Energy Technology Data Exchange (ETDEWEB)
Schochet, St.; Bresch, D.; Grenier, E.; Alazard, T.; Gordner, A.; Sankaran, V.; Massot, M.; Sery, R.; Pebay, P.; Lunch, O.; Mazhorova, O.; Turkel, O.E.; Faille, I.; Danchin, R.; Allain, O.; Birken, P.; Lafitte, O.; Kloczko, T.; Frick, W.; Bui, T.; Dellacherie, S.; Klein, R.; Roe, Ph.; Accary, G.; Braack, M.; Picano, F.; Cadiou, A.; Dinescu, C.; Lesage, A.C.; Wesseling, P.; Heuveline, V.; Jobelin, M.; Weisman, C.; Merkle, C.
2004-07-01
Low Mach number flows represent a significant part of the various flows encountered in geophysics, industry or every day life. Paradoxically, the mathematical analysis of the equations governing these flows is difficult and on the practical side, the research of numerical algorithms valid for all flow speeds is continuing to be a challenge. However, in the last decade, both from the theoretical and the numerical sides, significant progresses were made in the understanding and analysis of the equations governing these flows. This conference intends to provide an up-to-date inventory of recent mathematical and numerical results in the analysis of these flows by bringing together both mathematicians and numericists active in this area. In the framework of the conference, a numerical workshop is organized which proposes to compute several challenging low Mach number flows: liquid flow around non-cavitating and cavitating NACA0015 hydrofoil, natural convection with large temperature differences, free convection, free surface flow, vessel pressurization. This document brings together the descriptions of the test cases of the numerical workshop and the abstracts of the conference papers: A 3D high order finite volume method for the prediction of near-critical fluid flows (G. ACCARY, I. RASPO, P. BONTOUX, B. ZAPPOLI); low Mach number limit of the non-isentropic Navier-Stokes equations (T. ALAZARD); simulation of cavitation rolls past a forward step with a bubble model (O. ALLAIN, N. BLASKA, C. LECA); flux preconditioning methods and fire events (P. BIRKEN, A. MEISTER); an adaptive finite element solver for compressible flows: application to heat-driven cavity benchmarks in 2D and 3D (M. BRAACK); comparison of various implicit, explicit, centered and upwind schemes for the simulation of compressed flows on moving mesh (A. CADIOU, M. BUFFAT, L. Le PENVEN, C. Le RIBAULT); low Mach number limit for viscous compressible flows (R. DANCHIN); some Properties of the low Mach number
General Aspects of Tree Level Gauge Mediation
Nardecchia, Marco; Ziegler, Robert
2009-01-01
Tree level gauge mediation (TGM) may be considered as the simplest way to communicate supersymmetry breaking: through the tree level renormalizable exchange of heavy gauge messengers. We study its general structure, in particular the general form of tree level sfermion masses and of one loop, but enhanced, gaugino masses. This allows us to set up general guidelines for model building and to identify the hypotheses underlying the phenomenological predictions. In the context of models based on the "minimal" gauge group SO(10), we show that only two "pure" embeddings of the MSSM fields are possible using $d< 120$ representations, each of them leading to specific predictions for the ratios of family universal sfermion masses at the GUT scale, $m^2_{\\bar{5}} = 2 m^2_{10}$ or $m^2_{\\bar{5}} = (3/4) m^2_{10}$ (in SU(5) notation). These ratios are determined by group factors and are peculiar enough to make this scheme testable at the LHC. We also discuss three possible approaches to the $\\mu$-problem, one of them ...
Mathematical aspects of assessing extreme events for the safety of nuclear plants
Potempski, Slawomir; Borysiewicz, Mieczyslaw
2015-04-01
In the paper the review of mathematical methodologies applied for assessing low frequencies of rare natural events like earthquakes, tsunamis, hurricanes or tornadoes, floods (in particular flash floods and surge storms), lightning, solar flares, etc., will be given in the perspective of the safety assessment of nuclear plants. The statistical methods are usually based on the extreme value theory, which deals with the analysis of extreme deviation from the median (or the mean). In this respect application of various mathematical tools can be useful, like: the extreme value theorem of Fisher-Tippett-Gnedenko leading to possible choices of general extreme value distributions, or the Pickands-Balkema-de Haan theorem for tail fitting, or the methods related to large deviation theory. In the paper the most important stochastic distributions relevant for performing rare events statistical analysis will be presented. This concerns, for example, the analysis of the data with the annual extreme values (maxima - "Annual Maxima Series" or minima), or the peak values, exceeding given thresholds at some periods of interest ("Peak Over Threshold"), or the estimation of the size of exceedance. Despite of the fact that there is a lack of sufficient statistical data directly containing rare events, in some cases it is still possible to extract useful information from existing larger data sets. As an example one can consider some data sets available from the web sites for floods, earthquakes or generally natural hazards. Some aspects of such data sets will be also presented taking into account their usefulness for the practical assessment of risk for nuclear power plants coming from extreme weather conditions.
Mathematical theory of sedimentation analysis
Fujita, Hiroshi; Van Rysselberghe, P
1962-01-01
Mathematical Theory of Sedimentation Analysis presents the flow equations for the ultracentrifuge. This book is organized into two parts encompassing six chapters that evaluate the systems of reacting components, the differential equations for the ultracentrifuge, and the case of negligible diffusion. The first chapters consider the Archibald method for molecular weight determination; pressure-dependent sedimentation; expressions for the refractive index and its gradient; relation between refractive index and concentration; and the analysis of Gaussian distribution. Other chapters deal with th
Transform analysis of generalized functions
Misra, O P
1986-01-01
Transform Analysis of Generalized Functions concentrates on finite parts of integrals, generalized functions and distributions. It gives a unified treatment of the distributional setting with transform analysis, i.e. Fourier, Laplace, Stieltjes, Mellin, Hankel and Bessel Series.Included are accounts of applications of the theory of integral transforms in a distributional setting to the solution of problems arising in mathematical physics. Information on distributional solutions of differential, partial differential equations and integral equations is conveniently collected here.The volume will
TWO ASPECTS OF A GENERALIZED FIBONACCI SEQUENCE
Directory of Open Access Journals (Sweden)
Johan Matheus Tuwankotta
2015-05-01
Full Text Available In this paper we study the so-called generalized Fibonacci sequence: $x_{n+2} = \\alpha x_{n+1} + \\beta x_n, n\\in \\mathbb{N}$. We derive an open domain around the origin of the parameter space where the sequence converges to $0$. The limiting behavior on the boundary of this domain are: convergence to a nontrivial limit, $k$-periodic ($k\\in \\mathbb{N}$, or quasi-periodic. We use the ratio of two consecutive terms of the sequence to construct a rational approximation for algebraic numbers of the form: $\\sqrt{r}, r\\in \\mathbb{Q}$. Using a similar idea, we extend this to higher dimension to construct a rational approximation for $\\sqrt[3]{ a + b\\sqrt{c}} + \\sqrt[3]{ a - b\\sqrt{c}} + d$.
Topological aspects of generalized gravitational entropy
Energy Technology Data Exchange (ETDEWEB)
Haehl, Felix M. [Centre for Particle Theory & Department of Mathematical Sciences, Durham University,South Road, Durham DH1 3LE (United Kingdom); Hartman, Thomas [Department of Physics, Cornell University,Ithaca, New York 14853 (United States); Marolf, Donald [Department of Physics, University of California,Santa Barbara, Santa Barbara, CA 93106 (United States); Maxfield, Henry; Rangamani, Mukund [Centre for Particle Theory & Department of Mathematical Sciences, Durham University,South Road, Durham DH1 3LE (United Kingdom)
2015-05-05
The holographic prescription for computing entanglement entropy requires that the bulk extremal surface, whose area encodes the amount of entanglement, satisfies a homology constraint. Usually this is stated as the requirement of a (spacelike) interpolating surface that connects the region of interest and the extremal surface. We investigate to what extent this constraint is upheld by the generalized gravitational entropy argument, which relies on constructing replica symmetric q-fold covering spaces of the bulk, branched at the extremal surface. We prove (at the level of topology) that the putative extremal surface satisfies the homology constraint if and only if the corresponding branched cover can be constructed for every positive integer q. We give simple examples to show that homology can be violated if the cover exists for some values q but not others, along with some other issues.
Some Aspects of Mathematical Model of Collaborative Learning
Nakamura, Yasuyuki; Yasutake, Koichi; Yamakawa, Osamu
2012-01-01
There are some mathematical learning models of collaborative learning, with which we can learn how students obtain knowledge and we expect to design effective education. We put together those models and classify into three categories; model by differential equations, so-called Ising spin and a stochastic process equation. Some of the models do not…
A General Aspect of Platelet Rich Plasma
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Onur ORAL
2015-08-01
Full Text Available The aim of this scientific paper is to introduce Platelet Rich Plasma (PRP cure method by people who never heard about it. People can hurt their selves, thus they can have damaged tissue; for instance broken bone, a scar or a wounded area. Furthe rmore damaged tissue can be a cartilage tissue, which takes very long time to heal. Platelets, those exist in the veins as thrombus, come up to repair those damaged tissues. However, platelets would be insufficient to cure damaged area in a short time. At this point PRP cure method give a hand to the healing process. By centrifuging people’s own blood via special kits, platelets can be separated from blood cells as plasma. That plasma’s platelet density is 3 - 5 times greater than that blood’s platelet densit y. Afterwards PRP method is implemented by injection of plasma to the damaged area or tissue. After implementation of 2 - 4 sessions per week, damaged tissue can be regenerated. It is fast healing method because densified platelet plasma is used; and it is s afe because that plasma is obtained from people’s own blood. PRP can be implemented on many areas; for instance on dentistry, sports medicine, different kind of surgeries such as plastic, vascular or orthopedic and so on. When soccer players brake their le gs, their sports life come to the end, but what if their broken legs was healed better and faster than general healing process? To sum up, PRP is very safe and the future of healing process.
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
Probabilistic aspects of analysis and information operation of the system in situations of conflict
Directory of Open Access Journals (Sweden)
S. V. Gluschenko
2012-01-01
Full Text Available The problems of research of the parameters interaction structure and the conflict formation are considered in the stochastic systems by the general system theory. The mathematical aspects of relations conflict, promotion and indifference are analyzed. We consider the information approach for the analysis of the conflict.
Mathematical Analysis of Uncertainty
Directory of Open Access Journals (Sweden)
Angel GARRIDO
2016-01-01
Full Text Available Classical Logic showed early its insufficiencies for solving AI problems. The introduction of Fuzzy Logic aims at this problem. There have been research in the conventional Rough direction alone or in the Fuzzy direction alone, and more recently, attempts to combine both into Fuzzy Rough Sets or Rough Fuzzy Sets. We analyse some new and powerful tools in the study of Uncertainty, as the Probabilistic Graphical Models, Chain Graphs, Bayesian Networks, and Markov Networks, integrating our knowledge of graphs and probability.
Olympic Medal Counts: A Glimpse into Humanistic Aspects of Mathematics.
Borasi, Raffaella
1989-01-01
Develops an example demonstrating the existence of alternative solutions and the need for the use of personal judgment in mathematics. Uses a problem about ranking national performances at the 1988 Olympic Games as the example. Illustrates several different criteria and the results. (YP)
General aspects of immunotoxicology including validation issues
Frieke Kuper, C.
2006-01-01
Histologic examination of lymphoid organs has revealed immunotoxic effects of a broad range of substances. The thymus has proven especially sensitive. The relative lack of sensitivity of mucosa-associated lymphoid cells and tissues may be due to shortcomings in the way they are examined. Validation
General aspects of fertility and infertility.
Damario, Mark A
2014-01-01
Fertility rates have been declining in most Western nations over the past several decades, although it is not entirely clear if an increased rate of infertility substantially contributes to this. As compared to other species, the reproductive efficiency of humans is relatively low. Factors related to fertility include age, exposure to sexually transmitted diseases, frequency of intercourse, coital timing, as well as diet and lifestyle habits. Infertility is considered a disease due to its major disruption of major organ systems and life functions. An infertility evaluation is recommended after 12 months or more of regular, unprotected intercourse and may be considered after 6 months for those female patients over the age of 35 or with other known abnormalities. A proper infertility evaluation is a comprehensive examination of possibly identifiable infertility factors of both female and male partners, lending itself to the most appropriate and potentially effective treatment.
General relativistic aspects of ferromagneto-fluid
Energy Technology Data Exchange (ETDEWEB)
Asgekar, G.G.; Patwardhan, C.G.
1988-03-01
The implications of Bianchi identities pertaining to the spacetime of relativistic ferrofluid with infinite conductivity and variable magnetic permeability are investigated. Some kinematical and dynamical corollaries emerging out of a preferred geometrical symmetry called an isometry with respect to the flow vector and the magnetic field vector are developed.
General relativistic aspects of ferromagneto-fluid.
Asgekar, G. G.; Patwardhan, C. G.
1988-03-01
The implications of Bianchi identities pertaining to the spacetime of relativistic ferrofluid with infinite conductivity and variable magnetic permeability are investigated. Some kinematical and dynamical corollaries emerging out of a preferred geometrical symmetry called an isometry with respect to the flow vector and the magnetic field vector are developed.
General Aspects of Using the PACS
Directory of Open Access Journals (Sweden)
Afshin Niakan
2007-08-01
Full Text Available To reach to the optimum benefits of the PACS, we need to consider many things as followings:"nWe need a clear vision and mission about the usage and benefits of the PACS and also a clear data about the quality, quantity and extending the soft-ware that we will need in the future."nBefore installing the PACS, we must know the benefits of supplementary products and tools such as necessary hardware, network, internet, appropriate OS (especially for the servers, educated personnel, security of the system and data, disaster recovery plan which they are playing very important roles in performance and quality of the system."nWe should be aware of our needs about the integration of PACS and RIS/HIS, using the TeleRadiology, DICOMizer, standard reports as Structured Report (SR, image processing and computer aided diagnostic tools, stability of PACS and DICOM servers."nWe should be aware of the importance of software licenses and copyrights and also support the PACS, OS, Databases and other components especially when we want to store significant information and connect it through Internet."nThe budget of the system not only depends on the PACS software but also includes the price of hard-ware, network, image processing components, maintenance, upgrading, original OS, database and other supplementary tools."nWe are very proud to have ability for designing and producing these strategic and high technical products for the first time in open source platform in our region. We hope that you support the Iranian products and help us to improve our work for better competition with the best foreigner PACS
GENERAL ASPECTS OF NLP IN TEACHING LANGUAGES
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Clementina Niţă
2011-11-01
Full Text Available This article is focus on NLP as a tool helping to improve personal excellence in teaching languages. NLP states that learning begins in the students’ frame of reference and thus, it is important for teachers to increase their interpersonal skills and ability to recognize it. A map of how language operates is drawn by the Meta Model - a tool for a fuller understanding of what people say -, which deals with the concepts of surface structure and deep structure. The meta programs deal with deletions, distortions and generalisations which appear in language during communication. Establish rapport is a helpful method to create favourable teaching atmosphere and humanising teaching is a way to improve students’ performance.
General aspects of surface alloy formation
Energy Technology Data Exchange (ETDEWEB)
Bergbreiter, Andreas; Engstfeld, Albert K.; Roetter, Ralf T.; Hoster, Harry E.; Behm, R. Juergen [Institute of Surface Chemistry and Catalysis, Ulm University, D-89069 Ulm (Germany); Berko, Andras
2010-07-01
Surface confined alloys are excellent model systems for studies of structure-property relationships of bimetallic surfaces. They are formed by deposition of a guest metal B onto a substrate A, followed by annealing to a temperature, where place exchange between adatoms and atoms from the underlying surface layer becomes possible and diffusion into the bulk is sufficiently slow. We exemplarily confirmed by scanning tunneling microscopy and Auger electron spectroscopy for PtRu/Ru(0001), PdRu/Ru(0001), AuPt/Pt(111), AgPt/Pt(111), and AgPd/Pd(111), surface alloys are obtained for systems where metal B has a negative surface segregation energy within metal A. By exchanging A and B, however, AB surface alloys are most likely overgrown by metal B, which we demonstrate for RuPt/Pt(111) in comparison to PtRu/Ru(0001).
Relating Aspects of Motivation to Facets of Mathematical Competence Varying in Cognitive Demand
Gilbert, Melissa C.
2016-01-01
The author investigated the relationship between aspects of student motivation and performance on mathematical tasks varying in cognitive demand relevant to meeting the expectations of the Common Core State Standards for Mathematics (CCSS-M). A sample of 479 primarily Latino middle school students completed established survey measures of…
How to solve it a new aspect of mathematical method
Polya, G
2014-01-01
A perennial bestseller by eminent mathematician G. Polya, How to Solve It will show anyone in any field how to think straight. In lucid and appealing prose, Polya reveals how the mathematical method of demonstrating a proof or finding an unknown can be of help in attacking any problem that can be "reasoned" out-from building a bridge to winning a game of anagrams. Generations of readers have relished Polya's deft-indeed, brilliant-instructions on stripping away irrelevancies and going straight to the heart of the problem.
Different aspects of spatial skills and their relation to early mathematics
Cornu, Véronique; Hornung, Caroline; Schiltz, Christine; Martin, Romain
2016-01-01
We aimed at investigating the predictive role of spatial skills for arithmetic and number line estimation in kindergarten children (N = 125). Several studies highlighted the relation between spatial skills and mathematics. However, due to their non-unitary nature, different aspects of spatial skills need to be differentiated to clarify the relative importance of different aspects of spatial skills for mathematics. In the present study, at time 1, a spatial perception task, a spatial visualiza...
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.
Directory of Open Access Journals (Sweden)
E. V. Belik
2015-01-01
Full Text Available In this article the full potential of mathematical preparation of bachelors of teacher education in the context of increased activity in various areas of future professional activity. It is proposed to evaluate the possibility of mathematical preparation of future teachers in the terms of the decision of professional tasks in science and education. For this purpose, study was conducted, during which studied the opinion of practicing teachers of secondary schools, lyceums, gymnasiums of Rostov-on-Don for their attitude to the possibilities of mathematical education in the formation of readiness for innovation and research. As research methods were selected: 1 empirical methods: observation of the work of teachers, self-esteem; 2 psychodiagnostic methods: discussion, questioning; 3 mathematical methods: statistical methods of data processing. Method of survey was selected as the main. In total 176 respondents were interviewed. Survey data allowed the authors to conclude that the vast majority of teachers consider that it is necessary to have a certain mathematical preparation for professional activity on their profile. Based on the results of the study it was made a number of general methodological aspects of improving mathematical education of future teachers in the context of formation of readiness for the implementation of innovation and research. The value of the findings due to the fact that they are based on the practical experience of the application of mathematical apparatus in professional activities.
An Ecological Analysis of Mathematics Teachers' Noticing
Jazby, Dan
2016-01-01
Most studies which investigate mathematics teacher noticing cast perception into a passive role. This study develops an ecological analysis of mathematics teachers' noticing in order to investigate how teachers actively look for information in classroom environments. This method of analysis is applied to data collected as an experienced primary…
Mathematical aspects of molecular replacement. II. Geometry of motion spaces.
Chirikjian, Gregory S; Yan, Yan
2012-03-01
Molecular replacement (MR) is a well established computational method for phasing in macromolecular crystallography. In MR searches, spaces of motions are explored for determining the appropriate placement of rigid models of macromolecules in crystallographic asymmetric units. In the first paper of this series, it was shown that this space of motions, when endowed with an appropriate composition operator, forms an algebraic structure called a quasigroup. In this second paper, the geometric properties of these MR search spaces are explored and analyzed. This analysis includes the local differential geometry, global geometry and symmetry properties of these spaces.
Didactic Aspects of the Academic Discipline "History and Methodology of Mathematics"
Sun, Hai; Varankina, Vera I.; Sadovaya, Victoriya V.
2017-01-01
The purpose of this article is to develop the content and methods, as well as the analysis of the approbation of the program of the academic discipline "History and methodology of mathematics" for graduate students of the Master's program of mathematical program tracks. The leading method in the study of this problem was the method of…
Quality aspects of TMA analysis.
Tennstedt, Pierre; Sauter, Guido
2010-01-01
The quality of a TMA experiment can only be as good as the worst step in the entire process. Making and analyzing of tissue microarrays (TMAs) is a complex process involving tissue sample acquisition and preparation, expert histological diagnosis, long-term collection of clinical data, development of suitable laboratory protocols, the microscopic analysis, and the statistical analysis of the experiment. The quality of all these factors equally influences the outcome of TMA studies.
Non-selfadjoint operators in quantum physics mathematical aspects
Gazeau, Jean Pierre; Szafraniec, Franciszek Hugon; Znojil, Miloslav
2015-01-01
A unique discussion of mathematical methods with applications to quantum mechanics Non-Selfadjoint Operators in Quantum Physics: Mathematical Aspects presents various mathematical constructions influenced by quantum mechanics and emphasizes the spectral theory of non-adjoint operators. Featuring coverage of functional analysis and algebraic methods in contemporary quantum physics, the book discusses recent emergence of the unboundedness of metric operators, which is a serious issue in the study of parity-time-symmetric quantum mechanics. The book also answers mathematical questions that are currently the subject of rigorous analysis, with potentially significant physical consequences. In addition to prompting a discussion of the role of mathematical methods in the contemporary development of quantum physics, the book features: * Chapter contributions written by well-known mathematical physicists who clarify numerous misunderstandings and misnomers while shedding light on new approaches in this growing area *...
2015-02-04
Triangle Park, NC 27709-2211 mathematical modeling; physica modeling; computational methods ; conference organization REPORT DOCUMENTATION PAGE 11. SPONSOR...researchers from France and US working in the field of Mathematics and Mechanics . The Center has organized meetings every year over the past 7 years...is similar to that used in relativity to account for space curvature, but its application to mechanics of classical continua has not been explored
Mathematical theory of compressible viscous fluids analysis and numerics
Feireisl, Eduard; Pokorný, Milan
2016-01-01
This book offers an essential introduction to the mathematical theory of compressible viscous fluids. The main goal is to present analytical methods from the perspective of their numerical applications. Accordingly, we introduce the principal theoretical tools needed to handle well-posedness of the underlying Navier-Stokes system, study the problems of sequential stability, and, lastly, construct solutions by means of an implicit numerical scheme. Offering a unique contribution – by exploring in detail the “synergy” of analytical and numerical methods – the book offers a valuable resource for graduate students in mathematics and researchers working in mathematical fluid mechanics. Mathematical fluid mechanics concerns problems that are closely connected to real-world applications and is also an important part of the theory of partial differential equations and numerical analysis in general. This book highlights the fact that numerical and mathematical analysis are not two separate fields of mathematic...
Holographical aspects of dyonic black holes: Massive gravity generalization
Hendi, S H; Panahiyan, S
2016-01-01
The content of this paper includes studying holographical and thermodynamical aspects of dyonic black holes in the presence of massive gravity. For the first part of paper, the thermodynamical properties of the bulk which includes black holes are studied. The main focus is on critical behavior. It will be shown that the existence of massive gravitons introduces remnant for temperature for evaporation of black holes, van der Waals phase transition for non-spherical black holes and etc. The consistency of different thermodynamical approaches toward critical behavior of the black holes is proven and the physical properties near to the region of thermal instability are given. Next part of paper studies holographical aspects of the boundary theory. Magnetization and susceptibility of the boundary are extracted and the conditions for having diamagnetic and paramagnetic behaviors are investigated. It will be shown that generalization to massive gravity results into the existences of diamagnetic/paramagnetic phases i...
ASPECTS OF MATHEMATICAL MODELING AND INTERPRETATION OF A MANUFACTURING SYSTEM
Directory of Open Access Journals (Sweden)
Mihaela ALDEA
2013-05-01
Full Text Available In the paper developing we started from a model that allows a detailed decoding of causalrelationships and getting the laws that determine the evolution of the phenomenon.The model chosen for the study is a discrete event system applicable to optimize the transport systemused in pottery. In order to simulate the manufacturing process we chose Matlab package that contains pntoollibrary, by which can be realized modeling of analyzed graphs. Since the timings of manufacture are very highand the process simulation is conducted with difficulty, we divided the graph according to the transport system.
Wilfredo, Angulo
2014-01-01
We present some qualitative aspects concerning the solution to the mathematical model describing the dynamical behavior of the reversible chemical reaction SO2(g)+1/2O2(g)SO3(g) carried out in a catalytic reactor used in the process of sulfuric acid production.
Wilfredo, Angulo; Joyne, Contreras
2014-01-01
We present some qualitative aspects concerning the solution to the mathematical model describing the dynamical behavior of the reversible chemical reaction SO2(g)+1/2O2(g)SO3(g) carried out in a catalytic reactor used in the process of sulfuric acid production.
Simanowski, Stefanie; Krajewski, Kristin
2017-08-10
This study assessed the extent to which executive functions (EF), according to their factor structure in 5-year-olds (N = 244), influenced early quantity-number competencies, arithmetic fluency, and mathematics school achievement throughout first and second grades. A confirmatory factor analysis resulted in updating as a first, and inhibition and shifting as a combined second factor. In the structural equation model, updating significantly affected knowledge of the number word sequence, suggesting a facilitatory effect on basic encoding processes in numerical materials that can be learnt purely by rote. Shifting and inhibition significantly influenced quantity to number word linkages, indicating that these processes promote developing a profound understanding of numbers. These results show the supportive role of specific EF for specific aspects of a numerical foundation. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.
Zorich, Vladimir A
2015-01-01
VLADIMIR A. ZORICH is professor of mathematics at Moscow State University. His areas of specialization are analysis, conformal geometry, quasiconformal mappings, and mathematical aspects of thermodynamics. He solved the problem of global homeomorphism for space quasiconformal mappings. He holds a patent in the technology of mechanical engineering, and he is also known by his book Mathematical Analysis of Problems in the Natural Sciences . This second English edition of a very popular two-volume work presents a thorough first course in analysis, leading from real numbers to such advanced topics as differential forms on manifolds; asymptotic methods; Fourier, Laplace, and Legendre transforms; elliptic functions; and distributions. Especially notable in this course are the clearly expressed orientation toward the natural sciences and the informal exploration of the essence and the roots of the basic concepts and theorems of calculus. Clarity of exposition is matched by a wealth of instructive exercises, problems...
The matrix of the universe: logical - mathematical aspects
Directory of Open Access Journals (Sweden)
A. V. Reshetnichenko
2016-06-01
Full Text Available The article investigates the phenomenon of social reality, which, of course, has a certain historical and philosophical importance, and at the same time is very difficult, because the focus of the author - the search for new contexts of social reality in modern scientific discourse, which is extremely important, given the complex processes taking place today in the science and society. With the gradual increase in the array of post-classical social research it is becoming more apparent the difference between the approaches used by researchers working on the basis of the classical paradigm (they are now, of course, are in the majority, and an approach based on the post-classical teoretical methodology. Mastering the art of working with post-classical tools requires considerable effort, because education, as a rule, is based on the classical canons.Changes taking place in the modern world, the modern social and cultural situation, require the mobility of modern man and an adequate response to the requirements of modern society, and put it in front of the need to revise the traditional goals and targets. The authors show that in pedagogical terms, this means that the main result of education should not be a system of knowledge and skills in itself, but a set of core competencies in modern intellectual, social, legal, communication, information fields. Еspecially successful is the author uses the communicative model of social reality, allowing adequately describe the features of the functioning of the information society, to define the specifics of existing communication links arising between social space subjects. The author develops the idea that the communicative model of social reality implies the possibility of an authentic description of the information society, proved the relationship of discursive patterns of communication and problems of social simulacra with the specific modeling of virtual forms of social interactions in the
Aspects of Poincare's program for dynamical systems and mathematical physics
Verhulst, Ferdinand
2012-01-01
This article is mainly historical, except for the discussion of integrability and characteristic exponents in Sect. 2. After summarising the achievements of Henri Poincaré, we discuss his theory of critical exponents. The theory is applied to the case of three degreesof- freedom Hamiltonian systems
Some Aspects About Coalgebras In Mathematical Theory Of Programming
Directory of Open Access Journals (Sweden)
Valerie Novitzká
2009-10-01
Full Text Available Behavior of running program can be described by evaluating a coalgebraic structure over a collection of algebraic terms on state space. Coalgebras are defined by polynomial endofunctors. We formulate substantiation of coalgebras in categories. We use approach via Kleisli categories together with monads beside the approach via topoi and comonads as dual structures to monads.
Coulomb field of an accelerated charge physical and mathematical aspects
Alexander, F J; Alexander, Francis J.; Gerlach, Ulrich H.
1991-01-01
The Maxwell field equations relative to a uniformly accelerated frame, and the variational principle from which they are obtained, are formulated in terms of the technique of geometrical gauge invariant potentials. They refer to the transverse magnetic (TM) and the transeverse electric (TE) modes. This gauge invariant "2+2" decomposition is used to see how the Coulomb field of a charge, static in an accelerated frame, has properties that suggest features of electromagnetism which are different from those in an inertial frame. In particular, (1) an illustrative calculation shows that the Larmor radiation reaction equals the electrostatic attraction between the accelerated charge and the charge induced on the surface whose history is the event horizon, and (2) a spectral decomposition of the Coulomb potential in the accelerated frame suggests the possibility that the distortive effects of this charge on the Rindler vacuum are akin to those of a charge on a crystal lattice.
Aspects of Quantum Mathematics Hitchin Connections and AJ Conjectures
DEFF Research Database (Denmark)
Lauridsen, Magnus Roed
We discuss two different areas related to -dimensional Topological Quantum Field Theory, namely geometric quantization and the AJ-conjecture in knot theory. First, we construct a Hitchin connection in geometric quantization with metaplectic correction of symplectic manifolds, and compare...... it to previous constructions. Second, we review the AJ-conjecture in knot theory, relating the coloured Jones polynomial and the A-polynomial. We reformulate this conjecture geometrically, drawing on geometric quantization of moduli spaces. Last, we use Faddeev's quantum dilogarithm to describe the asymptotic...
Generalized functions, volume 4 applications of harmonic analysis
Gel′fand, I M; Vilenkin, N Ya
2016-01-01
The first systematic theory of generalized functions (also known as distributions) was created in the early 1950s, although some aspects were developed much earlier, most notably in the definition of the Green's function in mathematics and in the work of Paul Dirac on quantum electrodynamics in physics. The six-volume collection, Generalized Functions, written by I. M. Gel′fand and co-authors and published in Russian between 1958 and 1966, gives an introduction to generalized functions and presents various applications to analysis, PDE, stochastic processes, and representation theory. The main
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.
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.
Mathematical Analysis and Optimization of Infiltration Processes
Chang, H.-C.; Gottlieb, D.; Marion, M.; Sheldon, B. W.
1997-01-01
A variety of infiltration techniques can be used to fabricate solid materials, particularly composites. In general these processes can be described with at least one time dependent partial differential equation describing the evolution of the solid phase, coupled to one or more partial differential equations describing mass transport through a porous structure. This paper presents a detailed mathematical analysis of a relatively simple set of equations which is used to describe chemical vapor infiltration. The results demonstrate that the process is controlled by only two parameters, alpha and beta. The optimization problem associated with minimizing the infiltration time is also considered. Allowing alpha and beta to vary with time leads to significant reductions in the infiltration time, compared with the conventional case where alpha and beta are treated as constants.
Aspects of Classroom Discourse Analysis
Institute of Scientific and Technical Information of China (English)
丁蕾
2008-01-01
One influential approach to the study of spoken discourse is developed at the University of Birmingham in which the researchers initially concerned themselves with the strueture of discourse in school classroom. One of the interaction features of teacher-talk is to ask questions. They have attracted considerable attention from researchers of language classroom teaching.
ANALYSIS OF MATHEMATICS LITERACY BASED ON MATHEMATICAL ABILITY
Directory of Open Access Journals (Sweden)
Andes Safarandes Asmara
2017-05-01
Full Text Available This research was conducted to determine the literacy skills students of class X on their math skill. This study used a qualitative approach, the approach that drives meaningful results. To determine the ability of mathematical literacy class X, there were study subjects of 3 people who were selected based on their level of math skills. The determination was based on the categories of low, medium and high. Each subject was given a test and interview questions to determine the literacy skills. The results revealed that subjects with low category were in the second level of mathematics literacy, and subjects with high category were in the third level of mathematical literacy skills. Based on these results, it is necessary to seek strategies in the learning process of mathematics, which allows the improvement of mathematics literacy skills.
Mathematical Analysis of Evolution, Information, and Complexity
Arendt, Wolfgang
2009-01-01
Mathematical Analysis of Evolution, Information, and Complexity deals with the analysis of evolution, information and complexity. The time evolution of systems or processes is a central question in science, this text covers a broad range of problems including diffusion processes, neuronal networks, quantum theory and cosmology. Bringing together a wide collection of research in mathematics, information theory, physics and other scientific and technical areas, this new title offers elementary and thus easily accessible introductions to the various fields of research addressed in the book.
Rabitz, Herschel
1987-01-01
The use of parametric and functional gradient sensitivity analysis techniques is considered for models described by partial differential equations. By interchanging appropriate dependent and independent variables, questions of inverse sensitivity may be addressed to gain insight into the inversion of observational data for parameter and function identification in mathematical models. It may be argued that the presence of a subset of dominantly strong coupled dependent variables will result in the overall system sensitivity behavior collapsing into a simple set of scaling and self similarity relations amongst elements of the entire matrix of sensitivity coefficients. These general tools are generic in nature, but herein their application to problems arising in selected areas of physics and chemistry is presented.
Asquith, Becca; Bangham, Charles R M
2003-01-01
Mathematics is a useful tool in the analysis and understanding of population dynamic aspects of the immune response. However, the power of mathematical modelling in immunology is frequently limited by the shortage of experimental data. Here, we review the contribution of mathematics to two areas of immunology. We highlight the problem caused by lack of knowledge of the system, which can greatly restrict the use of mathematics and lead to errors caused by model-specific results.
Mathematical and statistical analysis
Houston, A. Glen
1988-01-01
The goal of the mathematical and statistical analysis component of RICIS is to research, develop, and evaluate mathematical and statistical techniques for aerospace technology applications. Specific research areas of interest include modeling, simulation, experiment design, reliability assessment, and numerical analysis.
In-Depth Mathematical Analysis of Ordinary High School Problems
Stanley, Dick; Walukiewicz, Jolanta
2004-01-01
The mathematical depth that is potentially present, even in simple problems is illustrated. An extended analysis of a problem that is an analysis from a mature mathematical perspective with careful attention paid to mathematical reasoning and to using good mathematical habits of mind is used.
In-Depth Mathematical Analysis of Ordinary High School Problems
Stanley, Dick; Walukiewicz, Jolanta
2004-01-01
The mathematical depth that is potentially present, even in simple problems is illustrated. An extended analysis of a problem that is an analysis from a mature mathematical perspective with careful attention paid to mathematical reasoning and to using good mathematical habits of mind is used.
Mathematical analysis of complex cellular activity
Bertram, Richard; Teka, Wondimu; Vo, Theodore; Wechselberger, Martin; Kirk, Vivien; Sneyd, James
2015-01-01
This book contains two review articles on mathematical physiology that deal with closely related topics but were written and can be read independently. The first article reviews the basic theory of calcium oscillations (common to almost all cell types), including spatio-temporal behaviors such as waves. The second article uses, and expands on, much of this basic theory to show how the interaction of cytosolic calcium oscillators with membrane ion channels can result in highly complex patterns of electrical spiking. Through these examples one can see clearly how multiple oscillatory processes interact within a cell, and how mathematical methods can be used to understand such interactions better. The two reviews provide excellent examples of how mathematics and physiology can learn from each other, and work jointly towards a better understanding of complex cellular processes. Review 1: Richard Bertram, Joel Tabak, Wondimu Teka, Theodore Vo, Martin Wechselberger: Geometric Singular Perturbation Analysis of Burst...
Correlates of the Orthodontic Aspects of the General Dentist's Practice.
Manasse, Robert J.; Dooley, Raynard J.
1980-01-01
A study undertaken to determine the extent of orthodontic referrals and treatment performed by general dentists is discussed. Results indicate that general practitioners who graduated after 1945 tend to make more referrals, and general practitioners who had treated patients orthodontically in their predoctoral training tend to continue in…
Correlates of the Orthodontic Aspects of the General Dentist's Practice.
Manasse, Robert J.; Dooley, Raynard J.
1980-01-01
A study undertaken to determine the extent of orthodontic referrals and treatment performed by general dentists is discussed. Results indicate that general practitioners who graduated after 1945 tend to make more referrals, and general practitioners who had treated patients orthodontically in their predoctoral training tend to continue in…
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
Fuchs, Lynn S; Fuchs, Douglas; Hamlett, Carol L; Lambert, Warren; Stuebing, Karla; Fletcher, Jack M
2008-02-01
The purpose of this study was to explore patterns of difficulty in 2 domains of mathematical cognition: computation and problem solving. Third graders (n = 924; 47.3% male) were representatively sampled from 89 classrooms; assessed on computation and problem solving; classified as having difficulty with computation, problem solving, both domains, or neither domain; and measured on 9 cognitive dimensions. Difficulty occurred across domains with the same prevalence as difficulty with a single domain; specific difficulty was distributed similarly across domains. Multivariate profile analysis on cognitive dimensions and chi-square tests on demographics showed that specific computational difficulty was associated with strength in language and weaknesses in attentive behavior and processing speed; problem-solving difficulty was associated with deficient language as well as race and poverty. Implications for understanding mathematics competence and for the identification and treatment of mathematics difficulties are discussed.
Infinitesimal methods of mathematical analysis
Pinto, J S
2004-01-01
This modern introduction to infinitesimal methods is a translation of the book Métodos Infinitesimais de Análise Matemática by José Sousa Pinto of the University of Aveiro, Portugal and is aimed at final year or graduate level students with a background in calculus. Surveying modern reformulations of the infinitesimal concept with a thoroughly comprehensive exposition of important and influential hyperreal numbers, the book includes previously unpublished material on the development of hyperfinite theory of Schwartz distributions and its application to generalised Fourier transforms and harmon
Mathematical Analysis of Genomic Evolution
Directory of Open Access Journals (Sweden)
Cedric Green
2011-01-01
Full Text Available Changes in nucleotide sequences, or mutations, accumulate from generation to generation in the genomes of all living organisms. The mutations can be advantageous, deleterious, or neutral. The goal of this project is to determine the amount of advantageous mutations it takes to get human (Homo sapiens DNA from the DNA of genetically distinct organisms. We do this by collecting the genomic data of such organisms, and estimating the amount of mutations it takes to transform yeast (Saccharomyces cerevisiae DNA to the DNA of a human. We calculate the typical number of mutations occurring annually through the organism's average life span and the average mutation rate. This allows us to determine the total number of mutations as well as the probability of advantageous mutations. Not surprisingly, this probability proves to be fairly small. A more precise estimate can be determined by accounting for the differences in the chromosomal structure and phenomena like horizontal gene transfer.
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
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.
The role of mathematics in physical sciences interdisciplinary and philosophical aspects
Boniolo, Giovanni; Trobok, Majda
2005-01-01
Even though mathematics and physics have been related for centuries and this relation appears to be unproblematic, there are many questions still open: Is mathematics really necessary for physics, or could physics exist without mathematics? Should we think physically and then add the mathematics apt to formalise our physical intuition, or should we think mathematically and then interpret physically the obtained results? Do we get mathematical objects by abstraction from real objects, or vice versa? Why is mathematics effective into physics? These are all relevant questions, whose answers are necessary to fully understand the status of physics, particularly of contemporary physics. The aim of this book is to offer plausible answers to such questions through both historical analyses of relevant cases, and philosophical analyses of the relations between mathematics and physics.
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…
Some Aspects of Quadratic Generalized White Noise Functionals
Si, Si; Hida, Takeyuki
2009-02-01
We shall discuss some particular roles of quadratic generalized white noise functionals. First observation is made from the viewpoint of the so-called "la passage du fini à l'infini". We then come to a dual pairing of spaces formed by quadratic generalized white noise functionals. In this line, we can further discuss quadratic forms of differential operators acting on the space of white noise functionals.
Aspects of Mathematical Modelling Applications in Science, Medicine, Economics and Management
Hosking, Roger J
2008-01-01
The construction of mathematical models is an essential scientific activity. Mathematics has long been associated with developments in the exact sciences and engineering, but more recently mathematical modelling has been used to investigate complex systems that arise in many other fields. The contributors to this book demonstrate the application of mathematics to modern research topics in ecology and environmental science, health and medicine, phylogenetics and neural networks, theoretical chemistry, economics and management.
Mathematical analysis differentiation and integration
Aramanovich, IG; Lyusternik, LA; Sneddon, I N
1965-01-01
Mathematical Analysis: Differentiation and Integration is devoted to two basic operations of mathematical analysis, differentiation and integration. The problems directly connected with the operations of differentiation and integration of functions of one or several variables are discussed, together with elementary generalizations of these operations. This volume is comprised of seven chapters and begins by considering the differentiation of functions of one variable and of n variables, paying particular attention to derivatives and differentials as well as their properties. The next chapter d
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…
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....
Baki, Mujgan
2015-01-01
This study aims to explore the role of lesson analysis in the development of mathematical knowledge for teaching. For this purpose, a graduate course based on lesson analysis was designed for novice mathematics teachers. Throughout the course the teachers watched videos of group-mates and discussed the issues they identified in terms of…
Directory of Open Access Journals (Sweden)
Truin Gert-Jan
2011-10-01
Full Text Available Abstract Background Considering the changes in dental healthcare, such as the increasing assertiveness of patients, the introduction of new dental professionals, and regulated competition, it becomes more important that general dental practitioners (GDPs take patients' views into account. The aim of the study was to compare patients' views on organizational aspects of general dental practices with those of GDPs and with GDPs' estimation of patients' views. Methods In a survey study, patients and GDPs provided their views on organizational aspects of a general dental practice. In a second, separate survey, GDPs were invited to estimate patients' views on 22 organizational aspects of a general dental practice. Results For 4 of the 22 aspects, patients and GDPs had the same views, and GDPs estimated patients' views reasonably well: 'Dutch-speaking GDP', 'guarantee on treatment', 'treatment by the same GDP', and 'reminder of routine oral examination'. For 2 aspects ('quality assessment' and 'accessibility for disabled patients' patients and GDPs had the same standards, although the GDPs underestimated the patients' standards. Patients had higher standards than GDPs for 7 aspects and lower standards than GDPs for 8 aspects. Conclusion On most aspects GDPs and patient have different views, except for social desirable aspects. Given the increasing assertiveness of patients, it is startling the GDP's estimated only half of the patients' views correctly. The findings of the study can assist GDPs in adapting their organizational services to better meet the preferences of their patients and to improve the communication towards patients.
Talking Mathematically: An Analysis of Discourse Communities
Imm, Kara; Stylianou, Despina A.
2012-01-01
Discourse has always been at the heart of teaching. In more recent years, the mathematics education community has also turned its attention towards understanding the role of discourse in mathematics teaching and learning. Using earlier classifications of discourse, in this paper, we looked at three types of classrooms: classrooms that engage in…
Aspects of Complexity in Sleep Analysis
Leitão, José M. N.; Da Rosa, Agostinho C.
The paper presents a selection of sleep analysis problems where some aspects and concepts of complexity come about. Emphasis is given to the electroencephalogram (EEG) as the most important sleep related variable. The conception of the EEG as a message to be deciphered stresses the importance of the communication and information theories in this field. An optimal detector of K complexes and vertex sharp waves based on a stochastic model of sleep EEG is considered. Besides detecting, the algorithm is also able to follow the evolution of the basic ongoing activity. It is shown that both the ostructure and microstructure of sleep can be described in terms of symbols and interpreted as sentences of a language. Syntactic models and Markov chain representations play in this context an important role.
Some Opinions on Normal College Mathematical Analysis Teaching
Institute of Scientific and Technical Information of China (English)
LUO Dong-sheng; WANG Chang-chun; TAN Xiao-yan
2014-01-01
Basing on the nature and special characters of normal college, talk about mathematical analysis teaching in several aspects.First, mathematical analysis should be taught as a foundation course because it will be used as one of the basic tools for further mathematics’study, and in the succeed course.The second, it being strictly relative with the primary mathematic course, so it should be taught as a guidance to pre-middle school mathematics teachers.The third, as any subject, getting the general structure of it is useful to let the students get the whole sensation, and help them to stimulate them to explore. Especially,for the future teacher, the course should build research interest and make the students know how to excite creation emotion from any subject as we do in mathematical analysis.
Profile of mathematics anxiety of 7th graders
Udil, Patrisius Afrisno; Kusmayadi, Tri Atmojo; Riyadi
2017-08-01
Mathematics anxiety is one of the important factors affect students mathematics achievement. This present research investigates profile of students' mathematics anxiety. This research focuses on analysis and description of students' mathematics anxiety level generally and its dominant domain and aspect. Qualitative research with case study strategy was used in this research. Subject in this research involved 15 students of 7th grade chosen with purposive sampling. Data in this research were students' mathematics anxiety scale result, interview record, and observation result during both mathematics learning activity and test. They were asked to complete mathematics anxiety scale before interviewed and observed. The results show that generally students' mathematics anxiety was identified in the moderate level. In addition, students' mathematics anxiety during mathematics test was identified in the high level, but it was in the moderate level during mathematics learning process. Based on the anxiety domain, students have a high mathematics anxiety on cognitive domain, while it was in the moderate level for psychological and physiological domains. On the other hand, it was identified in low level for psychological domain during mathematics learning process. Therefore, it can be concluded that students have serious and high anxiety regarding mathematics on the cognitive domain and mathematics test aspect.
Mathematical analysis of aircraft intercooler design
Joyner, Upshur T
1940-01-01
A mathematical analysis has been made to show the method of obtaining the dimensions of the intercooler that will use the least total power for a given set of design conditions. The results of this analysis have been used in a sample calculation and, on the basis of this calculation, a new inter cooler arrangement is suggested. Because the length of the two air passages of the new arrangement is short in comparison with the third dimension, the height of the intercooler, this intercooler arrangement has unusual dimensions. These dimensions give the proposed intercooler arrangement an advantage over one of usual dimensions because less total power will be consumed by the intercooler, the weight and volume of the intercooler will be smaller, and the pressure drop of both the engine air and the cooling air in passing through the intercooler will be lower.
Analytic and algorithmic aspects of generalized harmonic sums and polylogarithms
Energy Technology Data Exchange (ETDEWEB)
Ablinger, Jakob; Schneider, Carsten [Johannes Kepler Univ., Linz (Austria). Research Inst. for Symbolic Computation; Bluemlein, Johannes [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)
2013-01-15
In recent three-loop calculations of massive Feynman integrals within Quantum Chromodynamics (QCD) and, e.g., in recent combinatorial problems the so-called generalized harmonic sums (in short S-sums) arise. They are characterized by rational (or real) numerator weights also different from {+-}1. In this article we explore the algorithmic and analytic properties of these sums systematically. We work out the Mellin and inverse Mellin transform which connects the sums under consideration with the associated Poincare iterated integrals, also called generalized harmonic polylogarithms. In this regard, we obtain explicit analytic continuations by means of asymptotic expansions of the S-sums which started to occur frequently in current QCD calculations. In addition, we derive algebraic and structural relations, like differentiation w.r.t. the external summation index and different multi-argument relations, for the compactification of S-sum expressions. Finally, we calculate algebraic relations for infinite S-sums, or equivalently for generalized harmonic polylogarithms evaluated at special values. The corresponding algorithms and relations are encoded in the computer algebra package HarmonicSums.
Analysis of mathematical modelling on potentiometric biosensors.
Mehala, N; Rajendran, L
2014-01-01
A mathematical model of potentiometric enzyme electrodes for a nonsteady condition has been developed. The model is based on the system of two coupled nonlinear time-dependent reaction diffusion equations for Michaelis-Menten formalism that describes the concentrations of substrate and product within the enzymatic layer. Analytical expressions for the concentration of substrate and product and the corresponding flux response have been derived for all values of parameters using the new homotopy perturbation method. Furthermore, the complex inversion formula is employed in this work to solve the boundary value problem. The analytical solutions obtained allow a full description of the response curves for only two kinetic parameters (unsaturation/saturation parameter and reaction/diffusion parameter). Theoretical descriptions are given for the two limiting cases (zero and first order kinetics) and relatively simple approaches for general cases are presented. All the analytical results are compared with simulation results using Scilab/Matlab program. The numerical results agree with the appropriate theories.
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…
Public Health Aspects of Paediatric Dental Treatment under General Anaesthetic
Directory of Open Access Journals (Sweden)
William Murray Thomson
2016-06-01
Full Text Available Early childhood caries (ECC has negative psychosocial effects on children, with chronic pain, changed eating habits, disrupted sleep and altered growth very common, and it disrupts the day-to-day lives of their families. The treatment of young children with ECC places a considerable burden on health systems, with a considerable amount having to be provided under general anaesthesia (GA, which is resource-intensive. Justifying its use requires evidence of the efficacy of treatment in improving the lives of affected children and their families. This paper discusses the available evidence and then makes some suggestions for a research agenda.
Different Aspects of General Anesthesia in Pediatric Dentistry: A Review.
Ramazani, Nahid
2016-04-01
Most child population is able to undergo dental treatment in the conventional setting. However, some children fail to cope with in-office conscious state and cannot respond to usual management modalities. This review aims to discuss the topic further. A computerized search in databases PubMed, MEDLINE, EMBASE, Google Scholar and Google were performed using dental general anesthesia related keywords. Original and review English-written articles that were limited to child population were retrieved without any limitation of publication date. The suitable papers were selected and carefully studied. A data form designed by author was used to write relevant findings. Preoperative oral examination and comprehensive evaluation of treatment needs is only possible after clinical and radiographic oral examination. Effective collaboration in dental GA team should be made to minimize psychological trauma of children who undergo dental GA. Before conducting comprehensive dental treatment under GA, the general health of the child and the success rate of procedures provided needs to be accurately evaluated. It is noteworthy that determination of the optimal timing for GA dental operation is of great importance. Providing safety with pediatric dental rehabilitation under GA is critical. Besides criteria for case selection of dental GA, some degree of dental practitioner's judgment is required to make decision. Pre- and post-operative instructions to parents or caregiver decrease the risk of complications. However, trained resuscitation providers, careful monitoring and advanced equipment minimize adverse outcomes.
Mathematical analysis of a muscle architecture model.
Navallas, Javier; Malanda, Armando; Gila, Luis; Rodríguez, Javier; Rodríguez, Ignacio
2009-01-01
Modeling of muscle architecture, which aims to recreate mathematically the physiological structure of the muscle fibers and motor units, is a powerful tool for understanding and modeling the mechanical and electrical behavior of the muscle. Most of the published models are presented in the form of algorithms, without mathematical analysis of mechanisms or outcomes of the model. Through the study of the muscle architecture model proposed by Stashuk, we present the analytical tools needed to better understand these models. We provide a statistical description for the spatial relations between motor units and muscle fibers. We are particularly concerned with two physiological quantities: the motor unit fiber number, which we expect to be proportional to the motor unit territory area; and the motor unit fiber density, which we expect to be constant for all motor units. Our results indicate that the Stashuk model is in good agreement with the physiological evidence in terms of the expectations outlined above. However, the resulting variance is very high. In addition, a considerable 'edge effect' is present in the outer zone of the muscle cross-section, making the properties of the motor units dependent on their location. This effect is relevant when motor unit territories and muscle cross-section are of similar size.
Analysis of Research in the Teaching of Mathematics.
Brown, Kenneth E.; Abell, Theodore L.
This is the sixth in a series of publications prepared by the U.S. Office of Education which are concerned with an analysis of research in mathematics education. This publication presents a summary analysis of research in mathematics education and includes reports of Cooperative Research Projects supported by the Cooperative Research Program of…
Different Aspects of General Anesthesia in Pediatric Dentistry: A Review
National Research Council Canada - National Science Library
Ramazani, Nahid
2016-01-01
.... This review aims to discuss the topic further. A computerized search in databases PubMed, MEDLINE, EMBASE, Google Scholar and Google were performed using dental general anesthesia related keyword...
Mathematical methods of analysis of biopolymer sequences
Gindikin, S G
1992-01-01
This collection contains papers by participants in the seminar on mathematical methods in molecular biology who worked for several years at the Laboratory of Molecular Biology and Bioorganic Chemistry (now the Institute of Physical and Chemical Problems in Biology) at Moscow State University. The seminar united mathematicians and biologists around the problems of biological sequences. The collection includes original results as well as expository material and spans a range of perspectives, from purely mathematical problems to algorithms and their computer realizations. For this reason, the book is of interest to mathematicians, statisticians, biologists, and computational scientists who work with biopolymer sequences.
General aspects of solid on liquid growth mechanisms
Energy Technology Data Exchange (ETDEWEB)
Laux, E; Charmet, J; Haquette, H; Banakh, O; Jeandupeux, L; Graf, B; Keppner, H, E-mail: Herbert.Keppner@he-arc.c [University of Applied Science Arc, Eplatures-Grise 17, CH-2300 La Chaux-de-Fonds (Switzerland)
2009-08-01
Liquids, in general, tend to have a lower density as solids and therefore it is not straightforward to deposit solid over liquids in a way that the liquid becomes hermetically sealed under the solid layer. The authors review that several phenomena that can easily be observed in nature are only due to particular anomalies and solid on liquid is rather an exception as the rule. Natural solid on liquid systems are lacking of thermal, mechanical or chemical stability. It is not surprising, that one is not at all used thinking about to e.g. replace the gate oxide in a thin film transistor by a thin film of oil, or, to find in other microsystems functional liquids between a stack of thin solid films. However, once this becomes a serious option, a large variety of new Microsystems with new functionalities can be easily designed. In another paper (this conference and [1]) the authors pioneered that the polymer Parylene (poly(p-xylylene)) can be deposited on liquids coming already quite close to the above mentioned vision. In this paper the authors ask if one can synthesize other solid on liquid systems and surprisingly conclude, based on experimental evidence, that solid on liquid deposition seems to rather be the rule and not the exception.
Various aspects of sustainability analysis in Georgia
C. J. Cieszewski; M. Zasada; B. E. Borders; R. Lowe; M. L. Clutter; R. F. Daniels; R. Izlar
2002-01-01
In 2001 the Georgia Traditional Industries Program (TIP) sponsored a cooperative study at the D.B. Warnell School of Forest Resources, University of Georgia, to analyze the long-term sustainability of the fiber supply in Georgia. The subject of this study is relevant to a diverse array of disciplines, and it offers the opportunity to explore various aspects of...
Practical results from a mathematical analysis of guard patrols
Energy Technology Data Exchange (ETDEWEB)
Indusi, Joseph P.
1978-12-01
Using guard patrols as a primary detection mechanism is not generally viewed as a highly efficient detection method when compared to electronic means. Many factors such as visibility, alertness, and the space-time coincidence of guard and adversary presence all have an effect on the probability of detection. Mathematical analysis of the guard patrol detection problem is related to that of classical search theory originally developed for naval search operations. The results of this analysis tend to support the current practice of using guard forces to assess and respond to previously detected intrusions and not as the primary detection mechanism. 6 refs.
Pierce, Robyn; Stacey, Kaye; Wander, Roger; Ball, Lynda
2011-01-01
Current technologies incorporating sophisticated mathematical analysis software (calculation, graphing, dynamic geometry, tables, and more) provide easy access to multiple representations of mathematical problems. Realising the affordances of such technology for students' learning requires carefully designed lessons. This paper reports on design…
Pierce, Robyn; Stacey, Kaye; Wander, Roger; Ball, Lynda
2011-01-01
Current technologies incorporating sophisticated mathematical analysis software (calculation, graphing, dynamic geometry, tables, and more) provide easy access to multiple representations of mathematical problems. Realising the affordances of such technology for students' learning requires carefully designed lessons. This paper reports on design…
Razfar, Aria
2012-01-01
This article explores how the concepts of discourse and its methodological extension discourse analysis can help mathematics educators re-conceptualize their practices using a sociocultural view of learning. It provides conceptual and methodological tools as well as activities that can be helpful in mathematics methods courses and professional…
Different Aspects of General Anesthesia in Pediatric Dentistry: A Review
Nahid Ramazani
2016-01-01
Context Most child population is able to undergo dental treatment in the conventional setting. However, some children fail to cope with in-office conscious state and cannot respond to usual management modalities. This review aims to discuss the topic further. Evidence Acquisition A computerized search in databases PubMed, MEDLINE, EMBASE, Google Scholar and Google were performed using dental general anesthesia related keywords. Or...
General Aspects of some Causes of Web Application Vulnerabilities
Directory of Open Access Journals (Sweden)
Mironela Pîrnău
2015-10-01
Full Text Available Because web applications are complex software systems in constant evolution, they become real targets for hackers as they provide direct access to corporate or personal data. Web application security is supposed to represent an essential priority for organizations in order to protect sensitive customer data, or those of the employees of a company. Worldwide, there are many organizations that report the most common types of attacks on Web applications and methods for their prevention. While the paper is an overview, it puts forward several typical examples of web application vulnerabilities that are due to programming errors; these may be used by attackers to take unauthorized control over computers.
Mathematics analysis of polymerase chain reaction kinetic curves.
Sochivko, D G; Fedorov, A A; Varlamov, D A; Kurochkin, V E; Petrov, R V
2016-01-01
The paper reviews different approaches to the mathematical analysis of polymerase chain reaction (PCR) kinetic curves. The basic principles of PCR mathematical analysis are presented. Approximation of PCR kinetic curves and PCR efficiency curves by various functions is described. Several PCR models based on chemical kinetics equations are suggested. Decision criteria for an optimal function to describe PCR efficiency are proposed.
Mathematical aspects of Rietveld refinement and crystal structure studies on PbTiO3 ceramics
Indian Academy of Sciences (India)
Niranjan Sahu; S Panigrahi
2011-12-01
The core mathematics, goodness-of-fit parameters of Rietveld refinement technique is introduced for structural analysis of crystalline materials not available as single crystals. X-ray diffraction (XRD) patterns of PbTiO3 compound prepared by following solid-state route, suggests it to be in single crystal form. All the observed peaks could be indexed to $P4mm$ space group with tetragonal symmetry. XRD pattern is analysed by employing Rietveld method. The unit cell parameters are found to be = = 3.8987 (0.0008) Å and = 4.1380 (0.0009) Å. The axial ratio / and unit cell volume are found to be 1.0614 and 62.896 (0.023) Å3. Bond lengths and angles are calculated using the cell parameters. Using the Rietveld refinement parameters a stable PbTiO3 structure is suggested.
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.…
[Representation and mathematical analysis of human corneal surface].
Tălu, Stefan; Tălu, Mihai; Giovanzana, Stefano
2011-01-01
In the description and analysis of human corneal surface are used various mathematical models based on parametric representations, used in biomechanical studies and 3D solid modeling of the cornea. Mathematical models are important into the biomechanics of the cornea to model the corneal behavior. Corneal biomechanics also has the potential to improve outcomes in refractive surgery. The objective of this paper is to present the most representative mathematical models currently used for modeling of human corneal in optics and biomechanics fields.
Main Physical Aspects of the Mathematical Conception of Energy in Thermodynamics
Maslov, V P
2016-01-01
We consider the main physical notions and phenomena described by the author in his mathematical theory of thermodynamics. The new mathematical model yields the equation of state for a wide class of classical gases consisting of non-polar molecules provided that the spinodal, the critical isochore and the second virial coefficient are given. As an example, the spinodal, the critical isochore and the second virial coefficient are taken from the Van-der-Waals model. For this specific example, the isotherms constructed on the basis of the author's model are compared to the Van-der-Waals isotherms, obtained from completely different considerations.
SOME GENERAL ASPECTS OF ENGLISH FOR SPECIFIC PURPOSES
Institute of Scientific and Technical Information of China (English)
1999-01-01
The teaching of English for Specific Purposes has been in existence for over 30 years,and has beenprominence for more than 20 years,and is still in the ascendant.ESP teaching accounts for a consider-able proportion of the teaching of English as a foreign language in China.It is therefore necessary forus Chinese teacher s to know more about ESP.
Some theoretical aspects of human categorization behavior: similarity and generalization
Jäkel, Frank
2007-01-01
Explanations of human categorization behavior often invoke similarity. Stimuli that are similar to each other are grouped together whereas stimuli that are very different are kept separate. Despite serious problems in defining similarity, both conceptually and experimentally, this is the prevailing view of categorization in prototype models (Posner & Keele, 1968; Reed, 1972) and exemplar models (Medin & Schaffer, 1978; Nosofsky, 1986). This is also the prevailing approach in machine learning ...
Mathematical modeling of spinning elastic bodies for modal analysis.
Likins, P. W.; Barbera, F. J.; Baddeley, V.
1973-01-01
The problem of modal analysis of an elastic appendage on a rotating base is examined to establish the relative advantages of various mathematical models of elastic structures and to extract general inferences concerning the magnitude and character of the influence of spin on the natural frequencies and mode shapes of rotating structures. In realization of the first objective, it is concluded that except for a small class of very special cases the elastic continuum model is devoid of useful results, while for constant nominal spin rate the distributed-mass finite-element model is quite generally tractable, since in the latter case the governing equations are always linear, constant-coefficient, ordinary differential equations. Although with both of these alternatives the details of the formulation generally obscure the essence of the problem and permit very little engineering insight to be gained without extensive computation, this difficulty is not encountered when dealing with simple concentrated mass models.
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.
Quantitative Analysis of the Interdisciplinarity of Applied Mathematics.
Xie, Zheng; Duan, Xiaojun; Ouyang, Zhenzheng; Zhang, Pengyuan
2015-01-01
The increasing use of mathematical techniques in scientific research leads to the interdisciplinarity of applied mathematics. This viewpoint is validated quantitatively here by statistical and network analysis on the corpus PNAS 1999-2013. A network describing the interdisciplinary relationships between disciplines in a panoramic view is built based on the corpus. Specific network indicators show the hub role of applied mathematics in interdisciplinary research. The statistical analysis on the corpus content finds that algorithms, a primary topic of applied mathematics, positively correlates, increasingly co-occurs, and has an equilibrium relationship in the long-run with certain typical research paradigms and methodologies. The finding can be understood as an intrinsic cause of the interdisciplinarity of applied mathematics.
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...
Some mathematical aspects of the scaling limit of critical two-dimensional systems
Indian Academy of Sciences (India)
Wendelin Werner
2005-05-01
It has been observed long ago that many systems from statistical physics behave randomly on macroscopic level at their critical temperature. In two dimensions, these phenomena have been classified by theoretical physicists thanks to conformal field theory, that led to the derivation of the exact value of various critical exponents that describe their behavior near the critical temperature. In the last couple of years, combining ideas of complex analysis and probability theory, mathematicians have constructed and studied a family of random fractals (called `Schramm–Loewner evolutions' or SLE) that describe the only possible conformally invariant limits of the interfaces for these models. This gives a concrete construction of these random systems, puts various predictions on a rigorous footing, and leads to further understanding of their behavior. The goal of this paper is to survey some of these recent mathematical developments, and to describe a couple of basic underlying ideas. We will also briefly describe some very recent and ongoing developments relating SLE, Brownian loop soups and conformal field theory.
Donaldson, J. A.
1984-01-01
Simple continuum models used in the design, analysis, and control of large space structures are examined. Particular emphasis is placed on boundary value problems associated with the Load Correction Method and control problems involving partial differential equations for the large space structure models. Partial differential equations will be used to model a large space structure, base the design of an optimal controller on this model, approximate the resulting optimal control model, and compare the results with data from other methods.
Donaldson, J. A.
1984-01-01
Simple continuum models used in the design, analysis, and control of large space structures are examined. Particular emphasis is placed on boundary value problems associated with the Load Correction Method and control problems involving partial differential equations for the large space structure models. Partial differential equations will be used to model a large space structure, base the design of an optimal controller on this model, approximate the resulting optimal control model, and compare the results with data from other methods.
From geometry to numerics: interdisciplinary aspects in mathematical and numerical relativity
Energy Technology Data Exchange (ETDEWEB)
Jaramillo, Jose Luis [Instituto de AstrofIsica de AndalucIa, CSIC, Apartado Postal 3004, Granada 18080 (Spain); Valiente Kroon, Juan Antonio [School of Mathematical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom); Gourgoulhon, Eric [Laboratoire Univers et Theories, UMR 8102 du CNRS, Observatoire de Paris, Universite Paris Diderot, F-92190 Meudon (France)], E-mail: jarama@iaa.es, E-mail: j.a.valiente-kroon@qmul.ac.uk, E-mail: eric.gourgoulhon@obspm.fr
2008-05-07
This paper reviews some aspects in the current relationship between mathematical and numerical general relativity. Focus is placed on the description of isolated systems, with a particular emphasis on recent developments in the study of black holes. Ideas concerning asymptotic flatness, the initial-value problem, the constraint equations, evolution formalisms, geometric inequalities and quasi-local black hole horizons are discussed in light of the interaction between numerical and mathematical relativists. (topical review)
From Geometry to Numerics: interdisciplinary aspects in mathematical and numerical relativity
Jaramillo, J L; Gourgoulhon, E
2007-01-01
This article reviews some aspects in the current relationship between mathematical and numerical General Relativity. Focus is placed on the description of isolated systems, with a particular emphasis on recent developments in the study of black holes. Ideas concerning asymptotic flatness, the initial value problem, the constraint equations, evolution formalisms, geometric inequalities and quasilocal black hole horizons are discussed on the light of the interaction between numerical and mathematical relativists.
Generalized mathematical-computational-electronic model of MPTP- induced Parkinsonism
Jaramillo Raquejo, Daniela
2013-05-01
The substance 1-methyl-4-phenyl-1, 2, 3, 6 tetrahy dropyridine (MPTP) has been studied as a major cause of neurodegeneration dopaminica, which is specifically related to Parkinson's disease. The analysis is in terms of the diffusion of the substance to the mammalian brain, by evaluating the diffusion equation in a spherical coordinate system, being η (collective diffusion term) spatially modulated. Although the progress of the disease with respect to time has not been established with certainty, an attempt to find a stable pattern of the concentration of MPTP and its effects has been made.
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.
Canuto, Claudio
2015-01-01
The purpose of the volume is to provide a support textbook for a second lecture course on Mathematical Analysis. The contents are organised to suit, in particular, students of Engineering, Computer Science and Physics, all areas in which mathematical tools play a crucial role. The basic notions and methods concerning integral and differential calculus for multivariable functions, series of functions and ordinary differential equations are presented in a manner that elicits critical reading and prompts a hands-on approach to concrete applications. The pedagogical layout echoes the one used in the companion text Mathematical Analysis I. The book’s structure has a specifically-designed modular nature, which allows for great flexibility in the preparation of a lecture course on Mathematical Analysis. The style privileges clarity in the exposition and a linear progression through the theory. The material is organised on two levels. The first, reflected in this book, allows students to grasp the essential ideas, ...
Mathematical analysis fundamentals
Bashirov, Agamirza
2014-01-01
The author's goal is a rigorous presentation of the fundamentals of analysis, starting from elementary level and moving to the advanced coursework. The curriculum of all mathematics (pure or applied) and physics programs include a compulsory course in mathematical analysis. This book will serve as can serve a main textbook of such (one semester) courses. The book can also serve as additional reading for such courses as real analysis, functional analysis, harmonic analysis etc. For non-math major students requiring math beyond calculus, this is a more friendly approach than many math-centric o
Mathematical analysis of epidemiological models with heterogeneity
Energy Technology Data Exchange (ETDEWEB)
Van Ark, J.W.
1992-01-01
For many diseases in human populations the disease shows dissimilar characteristics in separate subgroups of the population; for example, the probability of disease transmission for gonorrhea or AIDS is much higher from male to female than from female to male. There is reason to construct and analyze epidemiological models which allow this heterogeneity of population, and to use these models to run computer simulations of the disease to predict the incidence and prevalence of the disease. In the models considered here the heterogeneous population is separated into subpopulations whose internal and external interactions are homogeneous in the sense that each person in the population can be assumed to have all average actions for the people of that subpopulation. The first model considered is an SIRS models; i.e., the Susceptible can become Infected, and if so he eventually Recovers with temporary immunity, and after a period of time becomes Susceptible again. Special cases allow for permanent immunity or other variations. This model is analyzed and threshold conditions are given which determine whether the disease dies out or persists. A deterministic model is presented; this model is constructed using difference equations, and it has been used in computer simulations for the AIDS epidemic in the homosexual population in San Francisco. The homogeneous version and the heterogeneous version of the differential-equations and difference-equations versions of the deterministic model are analyzed mathematically. In the analysis, equilibria are identified and threshold conditions are set forth for the disease to die out if the disease is below the threshold so that the disease-free equilibrium is globally asymptotically stable. Above the threshold the disease persists so that the disease-free equilibrium is unstable and there is a unique endemic equilibrium.
Philosophy of Mathematics, Mathematics Education and Philosophy of Mathematics Education.
Zheng, Yuxin
1994-01-01
Uses the modern development of mathematics education in the United States as background for the analysis of the influence of mathematics philosophy on mathematics education. Discusses the problem of how to develop the subject of philosophy of mathematics education, regarded as an impetus from mathematics education, to the further development of…
Mathematical Modeling for Simulation of Nuclear Reactor Analysis
Salah Ud-Din Khan; Shahab Ud-Din Khan
2013-01-01
In this paper, we have developed a mathematical model for the nuclear reactor analysis to be implemented in the nuclear reactor code. THEATRe is nuclear reactor analysis code which can only work for the cylindrical type fuel reactor and cannot applicable for the plate type fuel nuclear reactor. Therefore, the current studies encompasses on the modification of THEATRe code for the plate type fuel element. This mathematical model is applicable to the thermal analysis of the reactor which is ver...
Geoplano in the teaching of mathematics: Perspectives and some aspects of its use in the classroom
Directory of Open Access Journals (Sweden)
Dailson Evangelista Costa
2011-06-01
Full Text Available This article presents one of the researches carried out by the UFT Institutional Scholarship Program of Initiation to Teaching (PIBID. The topic addressed is about the teaching of plane geometry through Geoplano. We defend in this article, the idea that the teaching of mathematics using concrete or manipulatives materials becomes a possibility for the teaching. The Geoplano enables students to develop a better visual perception of geometric shapes facilitating the construction of certain problem situations, prompting students to investigate them, to solve them, and to engage in them constantly in the process. The perspective of the development of these activities is that one does not need to introduce a theme starting from the theory, but also from certain practical problems. In this sense, besides turning the teaching of math more "fun", such perspective will provide the learner the opportunity to experience situations different from the usual "boring lectures" thus contributing to the learning of mathematical knowledge. The proposal is to use the Rectangle Geoplano for teaching mathematical content creating new scenarios in the school environment, prioritizing research. We highlight some results obtained with the application of Geoplano in a public school, and the motivation that students showed in their use in math classes
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.
Blair, Clancy; Ursache, Alexandra; Greenberg, Mark; Vernon-Feagans, Lynne
2017-01-01
The relation of self-regulation measured prior to school entry to developing math and reading ability in prekindergarten through the second grade was examined in a prospective longitudinal sample of 1,292 children and families in predominantly rural and low-income communities in 2 regions of high poverty in the United States. Direct assessments of executive function, effortful control, and stress response physiology (indexed by resting levels of cortisol and alpha amylase obtained from saliva) were measured at child age 48 months and parents and teachers reported on children’s effortful control using temperament rating scales at child age approximately 60 months. Math and reading ability, as measured by the Woodcock-Johnson III applied problems and letter–word subtests, respectively, were measured at prekindergarten through the second grade. Effects for self-regulation measures were seen primarily for initial level and to some extent growth in both mathematics and reading, even when controlling for family demographic characteristics that represent relevant selection factors into higher levels of both self-regulation and academic achievement. These effects persisted for mathematics but not for reading with the inclusion of child cognitive abilities, vocabulary, and speed of processing measured in prekindergarten, concurrent with the first time point for the academic measures. Results are interpreted as indicating a role for self-regulation in learning ability generally, likely through support for attention and reasoning abilities that are most specific to the assessment of mathematics in this analysis. Implications for instruction and for assessment and the best ways to support the development of early math and reading ability for children at risk for school failure are discussed. PMID:25688999
Mathematical principles of signal processing Fourier and wavelet analysis
Brémaud, Pierre
2002-01-01
Fourier analysis is one of the most useful tools in many applied sciences. The recent developments of wavelet analysis indicates that in spite of its long history and well-established applications, the field is still one of active research. This text bridges the gap between engineering and mathematics, providing a rigorously mathematical introduction of Fourier analysis, wavelet analysis and related mathematical methods, while emphasizing their uses in signal processing and other applications in communications engineering. The interplay between Fourier series and Fourier transforms is at the heart of signal processing, which is couched most naturally in terms of the Dirac delta function and Lebesgue integrals. The exposition is organized into four parts. The first is a discussion of one-dimensional Fourier theory, including the classical results on convergence and the Poisson sum formula. The second part is devoted to the mathematical foundations of signal processing - sampling, filtering, digital signal proc...
Dulama, Maria Eliza; Magda?, Ioana
2014-01-01
In this paper, we analyze some aspects related to "Mathematics and Environmental Exploration" subject syllabus for preparatory grade approved by Minister of National Education of Romania. The analysis aim the place of the subject syllabus into the Framework Plan; the syllabus structure and the argumentation of studying this subject; the…
Mathematical analysis of multi-antibiotic resistance.
Zhao, Bin; Zhang, Xiaoying
2016-09-15
Multi-antibiotic resistance in bacterial infections is a growing threat to public health. Some experiments were carried out to study the multi-antibiotic resistance. The changes of the multi-antibiotic resistance with time were achieved by numerical simulations and the mathematical models, with the calculated temperature field, velocity field, and the antibiotic concentration field. The computed results and experimental results are compared. Both numerical simulations and the analytic models suggest that minor low concentrations of antibiotics could induce antibiotic resistance in bacteria. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
The physical and mathematical aspects of inverse problems in radiation detection and applications
Energy Technology Data Exchange (ETDEWEB)
Hussein, Esam M.A., E-mail: hussein@unb.ca [Laboratory for Threat Material Detection, Department of Mechanical Engineering, University of New Brunswick, Fredericton, NB, E3B 5A3 (Canada)
2012-07-15
The inverse problem is the problem of converting detectable measurements into useful quantifiable indications. It is the problem of spectrum unfolding, image reconstruction, identifying a threat material, or devising a radiotherapy plan. The solution of an inverse problem requires a forward model that relates the quantities of interest to measurements. This paper explores the physical issues associated with formulating a radiation-transport forward model best suited for inversion, and the mathematical challenges associated with the solution of the corresponding inverse problem.
Directory of Open Access Journals (Sweden)
Yuriy Michaylovich Chinyuchin
2017-01-01
Full Text Available The consistency of the potential increase of fuel efficiency, based on aircraft maintenance optimization, is mathe- matically proved. The mathematical apparatus and a set mathematical model of aircraft spatial motion allow to analyze aircraft behavior on the stage before landing and to draw optimal flight path for minimum fuel consumption with fixed time.For effective problem solving the choice and realization of optimal flight paths are made. The algorithm for the problem of optimal civil aircraft flight control aimed at the most accurate realization of chosen soft path under limited time conditions is proposed. The optimization of the given process is made by solving a point-to-point boundary canonical sys- tem based on the Pontryagin maximum principle.The necessary initial data and conditions for the statement of problem are given. The mathematical model for the simplification of calculations is created and its equivalent representation is given by uniting problems of controls by thrust channels and the angle of attack as the thrust control function. The boundary-value problem is mathematically composed and the analytical apparatus of its solution is presented. Optimal aircraft landing paths reflecting the behavior of the angle of attack and thrust are constructed. The potential of this method is proved by the economic justifiability and its effectiveness, in particular the compar- ison of total aircraft fuel consumption on obtained optimal path to the classic path on which there are rectilinear sections what allowed to confirm the conclusion about the economical expedience and effectiveness of the method of aircraft con- stant landing while making flights.
Advances in multiscale theoretical analysis and imaging aspects of turbulence
Shockro, Jennifer
turbulent jet scalar interface. Understanding aspects of turbulent interfacial behavior provides information about the manner in which directed lasers propagate through atmospheric turbulence, such as cloud formations and fog, and is necessary to the development of new technologies such as free-space laser communications. The mathematical basis of the M(3) method is described and is shown to be a theoretical approach that is useful for analysis of multiscale and multiorientation properties of level crossings of fluctuating fields, such as those present in experimental images of concentration fields and scalar interfaces in turbulent jets. The approach is based on considering the analytical relation between the shortest-distance probability density function and the generalized fractal dimension as a function of scale, and the corresponding orientation probability density function. The shortest distance refers to the distance between any randomly located point within a reference boundary to the nearest to part of the object of interest. For example, for a turbulent interface, the shortest distance is the distance between a random point and the nearest part of the interface. The orientation corresponding to the shortest-distance scale is the direction of the vector from the random point to the nearest part of the object, as in anisotropic studies. The method is used to analyze images obtained using laser Mie scattering of a fog seeded jet of air in an experimental flow facility. Care was taken in experiments to create a fog volume fraction that is both representative of certain natural fog occurrences and that ensures negligible effects on the turbulent geometric structures present. The Mie imaging and fog seeding of air are employed to quantitatively visualize the turbulent jet concentration field as a cross section of the jet and the images of the concentration field are used to extract scalar interfaces. The shortest-distance M(3) method is applied to theimaged scalar
Fielding-Wells, Jill; O'Brien, Mia; Makar, Katie
2017-03-01
Inquiry-based learning (IBL) is a pedagogical approach in which students address complex, ill-structured problems set in authentic contexts. While IBL is gaining ground in Australia as an instructional practice, there has been little research that considers implications for student motivation and engagement. Expectancy-value theory (Eccles and Wigfield 2002) provides a framework through which children's beliefs about their mathematical competency and their expectation of success are able to be examined and interpreted, alongside students' perceptions of task value. In this paper, Eccles and Wigfield's expectancy-value model has been adopted as a lens to examine a complete unit of mathematical inquiry as undertaken with a class of 9-10-year-old students. Data were sourced from a unit (˜10 lessons) based on geometry and geometrical reasoning. The units were videotaped in full, transcribed, and along with field notes and student work samples, subjected to theoretical coding using the dimensions of Eccles and Wigfield's model. The findings provide insight into aspects of IBL that may impact student motivation and engagement. The study is limited to a single unit; however, the results provide a depth of insight into IBL in practice while identifying features of IBL that may be instrumental in bringing about increased motivation and engagement of students in mathematics. Identifying potentially motivating aspects of IBL enable these to be integrated and more closely studied in IBL practises.
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.
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…
Associative Memory Biological and Mathematical Aspects.
1987-12-29
Kandel, Small systems of neurons, in The Brain, A Scientific American Book, W. H. Freeman and Company, San Francisco, 1979. . [7] W. S. McCulloch and...W. H. Pitts , A logical calculus of ideas immanent in nervous activity, Bulletin of Mathematical Biophysics, 1943. [8] D. 0. Hebb, The Organization of
Generalized analysis of molecular variance.
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Caroline M Nievergelt
2007-04-01
Full Text Available Many studies in the fields of genetic epidemiology and applied population genetics are predicated on, or require, an assessment of the genetic background diversity of the individuals chosen for study. A number of strategies have been developed for assessing genetic background diversity. These strategies typically focus on genotype data collected on the individuals in the study, based on a panel of DNA markers. However, many of these strategies are either rooted in cluster analysis techniques, and hence suffer from problems inherent to the assignment of the biological and statistical meaning to resulting clusters, or have formulations that do not permit easy and intuitive extensions. We describe a very general approach to the problem of assessing genetic background diversity that extends the analysis of molecular variance (AMOVA strategy introduced by Excoffier and colleagues some time ago. As in the original AMOVA strategy, the proposed approach, termed generalized AMOVA (GAMOVA, requires a genetic similarity matrix constructed from the allelic profiles of individuals under study and/or allele frequency summaries of the populations from which the individuals have been sampled. The proposed strategy can be used to either estimate the fraction of genetic variation explained by grouping factors such as country of origin, race, or ethnicity, or to quantify the strength of the relationship of the observed genetic background variation to quantitative measures collected on the subjects, such as blood pressure levels or anthropometric measures. Since the formulation of our test statistic is rooted in multivariate linear models, sets of variables can be related to genetic background in multiple regression-like contexts. GAMOVA can also be used to complement graphical representations of genetic diversity such as tree diagrams (dendrograms or heatmaps. We examine features, advantages, and power of the proposed procedure and showcase its flexibility by
Bardhan, Jaydeep P
2011-01-01
We analyze the mathematically rigorous BIBEE (boundary-integral based electrostatics estimation) approximation of the mixed-dielectric continuum model of molecular electrostatics, using the analytically solvable case of a spherical solute containing an arbitrary charge distribution. Our analysis, which builds on Kirkwood's solution using spherical harmonics, clarifies important aspects of the approximation and its relationship to Generalized Born models. First, our results suggest a new perspective for analyzing fast electrostatic models: the separation of variables between material properties (the dielectric constants) and geometry (the solute dielectric boundary and charge distribution). Second, we find that the eigenfunctions of the reaction-potential operator are exactly preserved in the BIBEE model for the sphere, which supports the use of this approximation for analyzing charge-charge interactions in molecular binding. Third, a comparison of BIBEE to the recent GB$\\epsilon$ theory suggests a modified BI...
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.
Some Aspects of Analysis of a Micromirror
Dipti Razdan; A.B. Chattopadhyay
2015-01-01
Micromirror is a very small mirror based on the principle of Micro Electro Mechanical Systems (MEMS). Micromirror application in areas like laser scanning displays, DLP Projection system and HDTV are realized using MEMS technology. In this study, an electrostatically controlled micromirror is designed using COMSOL multi-physics software. The structural and mechanical properties of the actuation mechanism of various shapes of a micro-mirror will be studied. The base materials used will include...
Some Aspects of Analysis of a Micromirror
Directory of Open Access Journals (Sweden)
Dipti Razdan
2015-06-01
Full Text Available Micromirror is a very small mirror based on the principle of Micro Electro Mechanical Systems (MEMS. Micromirror application in areas like laser scanning displays, DLP Projection system and HDTV are realized using MEMS technology. In this study, an electrostatically controlled micromirror is designed using COMSOL multi-physics software. The structural and mechanical properties of the actuation mechanism of various shapes of a micro-mirror will be studied. The base materials used will include Copper, Silicon and Aluminum. To make the cantilever more efficient, the structural steel was introduced along with the base materials listed above so as to obtain the displacement of the mirror. In order to evaluate the mirror further, the analytical formulation for Capacitance and Torque are developed and compared to the calculated theoretical values. The final results are shown as a range of wavelength, which will be obtained taking into consideration the tilting angle obtained from various materials used for the designing of the mirrors.
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
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.
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.
Mathematical Background of Formalism of Operator Manifold
Ter-Kazarian, G T
1997-01-01
The analysis of mathematical structure of the method of operator manifold guides our discussion. The latter is a still wider generalization of the method of secondary quantization with appropriate expansion over the geometric objects. The nature of operator manifold provides its elements with both quantum field and geometry aspects, a detailed study of which is a subject of present paper. It yields a quantization of geometry differing in principle from all earlier suggested schemes.
A Mathematical Analysis of Conflict Prevention Information
Maddalon, Jeffrey M.; Butler, Ricky W.; Munoz, Cesar A.; Dowek, Gilles
2009-01-01
In air traffic management, conflict prevention information refers to the guidance maneuvers, which if taken, ensure that an aircraft's path is conflict-free. These guidance maneuvers take the form of changes to track angle or ground speed. Conflict prevention information may be assembled into prevention bands that advise the crew on maneuvers that should not be taken. Unlike conflict resolution systems, which presume that the aircraft already has a conflict, conflict prevention systems show conflicts for any maneuver, giving the pilot confidence that if a maneuver is made, then no near-term conflicts will result. Because near-term conflicts can lead to safety concerns, strong verification of information correctness is required. This paper presents a mathematical framework to analyze the correctness of algorithms that produce conflict prevention information incorporating an arbitrary number of traffic aircraft and with both a near-term and intermediate-term lookahead times. The framework is illustrated with a formally verified algorithm for 2-dimensional track angle prevention bands.
Kopeliovich, Vladimir B
2016-01-01
The angular dependence of the cumulative particles production off nuclei near the kinematical boundary for multistep process is defined by characteristic polynomials in angular variables $J_N^2(z_N^\\theta)$, where $\\theta$ is the polar angle defining the momentum of the final (cumulative) particle, $z_N^\\theta = cos (\\theta/N)$, the integer $N$ being the multiplicity of the process (the number of interactions). Physical argumentation, exploring the small phase space method, leads to the appearance of equations for these polynomials $J_N^2[cos(\\pi/N)]=0$. The recurrent relations between polynomials with different $N$ are obtained, and their connection with known in mathematics Chebyshev polynomials of 2-d kind is established. As a result of this equality, differential cross section of the cumulative particle production has characteristic behaviour $d\\sigma \\sim 1/ \\sqrt {\\pi - \\theta}$ at $\\theta \\sim \\pi$ (the backward focusing effect). Such behaviour takes place for any multiplicity of the interaction, begin...
Analysis of mathematical model for micromechanical vibratory wheel gyroscope
Institute of Scientific and Technical Information of China (English)
LUO Yue-sheng; FAN Chong-jin; TAN Zhen-fan
2003-01-01
By the sketch of structure of MVWG,the working laws of this kind of gyroscope were explained.To the aid of Euler′s Dynamics Equation,a mathematical model of the gyroscope was constructed,and then by the basic working laws of MVWG the model was simplified.Under the conditions of the three axial direction rotations and general rotation,the mathematical model was resolved.And finally by the solutions, the working laws of the gyroscope, the working disparity among all sorts of gyrations and the influences from the gyrations in the axial directions were analysed.
Bondarovskaya, V. M.
1975-01-01
The psychological analysis of programmer activity showed that one of its basic characteristics is the need to employ formal languages. In determining ways of effectively mastering the capacity to write algorithms in the algorithmic language, it is expedient to proceed from its similarity to the living languages and the language of mathematical formulas, and to choose certain psychological principles of mastering foreign languages and mathematical symbols in teaching the algorithmic language. General models of the input language significantly increase the effectiveness of its mastery and permit the development of thinking on the part of the students.
Procedural norms in the system of procedural law: general theoretical aspect
Атаманчук, Ірина Володимирівна; Університет сучасних знань
2015-01-01
Based on the distinguishing of particular system qualities, we study the concept, content, features of procedural rules, analize the development dynamics of the operating rules of the system of national procedural law. It’s concluded that there is a unity of procedural rules and the ways of their settlement, which states the need of substantive norms’ implementation. English abstract I. Atamanchuk Procedural norms in the system of procedural law: general theoretical aspect Based on the dist...
Concepts of modern mathematics
Stewart, Ian
1995-01-01
Some years ago, ""new math"" took the country's classrooms by storm. Based on the abstract, general style of mathematical exposition favored by research mathematicians, its goal was to teach students not just to manipulate numbers and formulas, but to grasp the underlying mathematical concepts. The result, at least at first, was a great deal of confusion among teachers, students, and parents. Since then, the negative aspects of ""new math"" have been eliminated and its positive elements assimilated into classroom instruction.In this charming volume, a noted English mathematician uses humor an
Aspects regarding the analysis of inflation evolution
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Constantin ANGHELACHE
2012-11-01
Full Text Available With this work, the authors are submitting the main theories, which led to the definition of the concept of “inflation”, pointing out the successive acceptations, which the economists – starting with classics, Adam Smith’s contemporaries – have granted, over the time, to this economical phenomenon. Thus, at a first phase, the term of inflation was connected to currency, later on to money while presently it is commonly used for describing prices. This change of paradigm seems to originate in a sequence of unhappy events, probably unavoidable.
Analysis of Corporate Environmental Management: Methodological Aspects
DEFF Research Database (Denmark)
Madsen, Henning; Ulhøi, John Parm
2001-01-01
in business presents a challenge to management, however, since it implies a fundamental change in some of the ways of operating a company. This paper will briefly discuss how information on the actual extent of environmental management in Danish companies and the way it is applied has been collected based......Human activities cannot avoid influencing conditions in the natural environment one way or the other. This includes as well common activities in the business sector. But during the past few decades, environmental disasters in Seveso and Bhopal, and the Exxon Valdes oil spill in Alaska have...... contributed to an increasing awareness of the effect of business activities on the physical environment. To assist companies reduce, evaluate, monitor and control their environmental impact the concept of corporate environmental and resource management has been developed. Implementation of this concept...
Aspects on the analysis of 210Po
DEFF Research Database (Denmark)
Henricsson, F.; Ranebo, Y.; Holm, E.
2011-01-01
will be too low. Both these systematic errors give rise to a too high 210Po/210Pb ratio. The fraction of 210Pb which is plating out has been assessed in this study for different matrices and is about 50–90%. During the measurement by solid state Si-detectors, some Po is evaporated in the vacuum conditions......-ashing by the use of a double-tracer technique. We have found that the losses were about 30% when open glass beakers were used and about 17% when the samples were digested in microwave oven. When long-necked bottles (Kjeldahl flasks) were used, a loss of about 20% was registered. It has also been observed that 210...
Mathematical analysis of a Vuilleumier refrigerator.
Sherman, A.
1971-01-01
A comprehensive analysis of the Vuilleumier refrigerator was conducted. This analysis includes the effects of nonisothermal gas heat addition and rejection, hot and cold regenerator inefficiencies, conduction losses, and gas leakage losses. A computer program was written which solves the equations resulting from the analysis. The program calculates internal pressures, temperatures, and gas flow rates as functions of refrigerator crank angle, as well as overall refrigerator cooling load and power input. Comparisons between the program results and available data show good agreement, with a marked improvement over the predictions of the ideal model.
Mathematical analysis of a Vuilleumier refrigerator.
Sherman, A.
1971-01-01
A comprehensive analysis of the Vuilleumier refrigerator was conducted. This analysis includes the effects of nonisothermal gas heat addition and rejection, hot and cold regenerator inefficiencies, conduction losses, and gas leakage losses. A computer program was written which solves the equations resulting from the analysis. The program calculates internal pressures, temperatures, and gas flow rates as functions of refrigerator crank angle, as well as overall refrigerator cooling load and power input. Comparisons between the program results and available data show good agreement, with a marked improvement over the predictions of the ideal model.
Generalized Stieltjes transforms: basic aspects
Karp, Dmitry
2011-01-01
The paper surveys the basic properties of generalized Stieltjes functions including some new ones. We introduce the notion of exact Stieltjes order and give a criterion of exactness, simple sufficient conditions and some prototypical examples. The paper includes an appendix, where we define the left sided Riemann-Liouville and the right sided Kober-Erdelyi fractional integrals of measures supported on half axis and give inversion formulas for them.
Mathematics for the analysis of algorithms
Greene, Daniel H
1990-01-01
This monograph, derived from an advanced computer science course at Stanford University, builds on the fundamentals of combinatorial analysis and complex variable theory to present many of the major paradigms used in the precise analysis of algorithms, emphasizing the more difficult notions. The authors cover recurrence relations, operator methods, and asymptotic analysis in a format that is terse enough for easy reference yet detailed enough for those with little background. Approximately half the book is devoted to original problems and solutions from examinations given at Stanford.
Computational Aspects of Dam Risk Analysis: Findings and Challenges
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Ignacio Escuder-Bueno
2016-09-01
Full Text Available In recent years, risk analysis techniques have proved to be a useful tool to inform dam safety management. This paper summarizes the outcomes of three themes related to dam risk analysis discussed in the Benchmark Workshops organized by the International Commission on Large Dams Technical Committee on “Computational Aspects of Analysis and Design of Dams.” In the 2011 Benchmark Workshop, estimation of the probability of failure of a gravity dam for the sliding failure mode was discussed. Next, in 2013, the discussion focused on the computational challenges of the estimation of consequences in dam risk analysis. Finally, in 2015, the probability of sliding and overtopping in an embankment was analyzed. These Benchmark Workshops have allowed a complete review of numerical aspects for dam risk analysis, showing that risk analysis methods are a very useful tool to analyze the risk of dam systems, including downstream consequence assessments and the uncertainty of structural models.
Some Aspects of Mathematical and Physical Approaches for Topological Quantum Computation
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V. Kantser
2011-10-01
Full Text Available A paradigm to build a quantum computer, based on topological invariants is highlighted. The identities in the ensemble of knots, links and braids originally discovered in relation to topological quantum field theory are shown: how they define Artin braid group -- the mathematical basis of topological quantum computation (TQC. Vector spaces of TQC correspond to associated strings of particle interactions, and TQC operates its calculations on braided strings of special physical quasiparticles -- anyons -- with non-Abelian statistics. The physical platform of TQC is to use the topological quantum numbers of such small groups of anyons as qubits and to perform operations on these qubits by exchanging the anyons, both within the groups that form the qubits and, for multi-qubit gates, between groups. By braiding two or more anyons, they acquire up a topological phase or Berry phase similar to that found in the Aharonov-Bohm effect. Topological matter such as fractional quantum Hall systems and novel discovered topological insulators open the way to form system of anyons -- Majorana fermions -- with the unique property of encoding and processing quantum information in a naturally fault-tolerant way. In the topological insulators, due to its fundamental attribute of topological surface state occurrence of the bound, Majorana fermions are generated at its heterocontact with superconductors. One of the key operations of TQC -- braiding of non-Abelian anyons: it is illustrated how it can be implemented in one-dimensional topological isolator wire networks.
Practical aspects of backward bifurcation in a mathematical model for tuberculosis.
Gerberry, David J
2016-01-01
In this work, we examine practical aspects of backward bifurcation for a data-based model of tuberculosis that incorporates multiple features which have previously been shown to produce backward bifurcation (e.g. exogenous reinfection and imperfect vaccination) and new considerations such as the treatment of latent TB infection (LTBI) and the BCG vaccine's interference with detecting LTBI. Understanding the interplay between these multiple factors and backward bifurcation is particularly timely given that new diagnostic tests for LTBI detection could dramatically increase rates of both LTBI detection and vaccination in the coming decades. By establishing analytic thresholds for the existence of backward bifurcation, we identify those aspects of TB's complicated pathology that make backward bifurcation more or less likely to occur. We also examine the magnitude of the backward bifurcation produced by the model and its sensitivity to various model parameters. We find that backward bifurcation is unlikely to occur. While increased vaccine coverage and/or increased detection and treatment of LTBI can push the threshold for backward bifurcation into the region of biological plausibility, the resulting bifurcations may still be too small to have any noticeable epidemiological impact.
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…
A Generalized Mathematical Model for the Fracture Problem of the Suspended Highway
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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.
Toward an Analysis of Video Games for Mathematics Education
Offenholley, Kathleen
2011-01-01
Video games have tremendous potential in mathematics education, yet there is a push to simply add mathematics to a video game without regard to whether the game structure suits the mathematics, and without regard to the level of mathematical thought being learned in the game. Are students practicing facts, or are they problem-solving? This paper…
Lake, Warren; Wallin, Margie; Woolcott, Geoff; Boyd, Wendy; Foster, Alan; Markopoulos, Christos; Boyd, William
2017-01-01
Student mathematics performance and the need for work-ready graduates to be mathematics-competent is a core issue for many universities. While both student and teacher are responsible for learning outcomes, there is a need to explicitly acknowledge the weak mathematics foundation of many university students. A systematic literature review was…
Lake, Warren; Wallin, Margie; Woolcott, Geoff; Boyd, Wendy; Foster, Alan; Markopoulos, Christos; Boyd, William
2017-01-01
Student mathematics performance and the need for work-ready graduates to be mathematics-competent is a core issue for many universities. While both student and teacher are responsible for learning outcomes, there is a need to explicitly acknowledge the weak mathematics foundation of many university students. A systematic literature review was…
Group Classification of a General Bond-Option Pricing Equation of Mathematical Finance
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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.
2012-01-01
This study has been planned for the purpose of comparative analysis of examination questions of elementary mathematics teachers and mathematics questions of Placement Examination (SBS) for 6th, 7th and 8th grades in 2010 in terms of Bloom’s Taxonomy. Document analysis method was used in this study. Accordingly, 715 examination questions mathematics teachers working in 12 different primary schools asked in 2009-2010 academic year and 54 mathematics questions for 6th, 7th and 8th grades in SBS ...
Generalized Analysis of a Distribution Separation Method
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Peng Zhang
2016-04-01
Full Text Available Separating two probability distributions from a mixture model that is made up of the combinations of the two is essential to a wide range of applications. For example, in information retrieval (IR, there often exists a mixture distribution consisting of a relevance distribution that we need to estimate and an irrelevance distribution that we hope to get rid of. Recently, a distribution separation method (DSM was proposed to approximate the relevance distribution, by separating a seed irrelevance distribution from the mixture distribution. It was successfully applied to an IR task, namely pseudo-relevance feedback (PRF, where the query expansion model is often a mixture term distribution. Although initially developed in the context of IR, DSM is indeed a general mathematical formulation for probability distribution separation. Thus, it is important to further generalize its basic analysis and to explore its connections to other related methods. In this article, we first extend DSM’s theoretical analysis, which was originally based on the Pearson correlation coefficient, to entropy-related measures, including the KL-divergence (Kullback–Leibler divergence, the symmetrized KL-divergence and the JS-divergence (Jensen–Shannon divergence. Second, we investigate the distribution separation idea in a well-known method, namely the mixture model feedback (MMF approach. We prove that MMF also complies with the linear combination assumption, and then, DSM’s linear separation algorithm can largely simplify the EM algorithm in MMF. These theoretical analyses, as well as further empirical evaluation results demonstrate the advantages of our DSM approach.
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…
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…
Mathematical Analysis of Urban Spatial Networks
Blanchard, Philippe
2009-01-01
Cities can be considered to be among the largest and most complex artificial networks created by human beings. Due to the numerous and diverse human-driven activities, urban network topology and dynamics can differ quite substantially from that of natural networks and so call for an alternative method of analysis. The intent of the present monograph is to lay down the theoretical foundations for studying the topology of compact urban patterns, using methods from spectral graph theory and statistical physics. These methods are demonstrated as tools to investigate the structure of a number of real cities with widely differing properties: medieval German cities, the webs of city canals in Amsterdam and Venice, and a modern urban structure such as found in Manhattan. Last but not least, the book concludes by providing a brief overview of possible applications that will eventually lead to a useful body of knowledge for architects, urban planners and civil engineers.
Harmonic Analysis : special program at the Nankai Institute of Mathematics
Deng, Dong-Gao; Zhou, Xing-Wei
1991-01-01
All papers in this volume are original (fully refereed) research reports by participants of the special program on Harmonic Analysis held in the Nankai Institute of Mathematics. The main themes include: Wavelets, Singular Integral Operators, Extemal Functions, H Spaces, Harmonic Analysis on Local Domains and Lie Groups, and so on. See also :G. David "Wavelets and Singular Integrals on Curves and Surfaces", LNM 1465,1991. FROM THE CONTENTS: D.C. Chang: Nankai Lecture in -Neumann Problem.- T.P. Chen, D.Z. Zhang: Oscillary Integral with Polynomial Phase.- D.G. Deng, Y.S. Han: On a Generalized Paraproduct Defined by Non-Convolution.- Y.S. Han: H Boundedness of Calderon-Zygmund Operators for Product Domains.- Z.X. Liu, S.Z. Lu: Applications of H|rmander Multiplier Theorem to Approximation in Real Hardy Spaces.- R.L. Long, F.S. Nie: Weighted Sobolev Inequality and Eigenvalue Estimates of Schr|dinger Operator.- A. McIntosh, Q. Tao: Convolution Singular Integral Operators on Lipschitz Curves.- Z.Y. Wen, L.M.Wu, Y.P. ...
Mathematical models of ABE fermentation: review and analysis.
Mayank, Rahul; Ranjan, Amrita; Moholkar, Vijayanand S
2013-12-01
Among different liquid biofuels that have emerged in the recent past, biobutanol produced via fermentation processes is of special interest due to very similar properties to that of gasoline. For an effective design, scale-up, and optimization of the acetone-butanol-ethanol (ABE) fermentation process, it is necessary to have insight into the micro- and macro-mechanisms of the process. The mathematical models for ABE fermentation are efficient tools for this purpose, which have evolved from simple stoichiometric fermentation equations in the 1980s to the recent sophisticated and elaborate kinetic models based on metabolic pathways. In this article, we have reviewed the literature published in the area of mathematical modeling of the ABE fermentation. We have tried to present an analysis of these models in terms of their potency in describing the overall physiology of the process, design features, mode of operation along with comparison and validation with experimental results. In addition, we have also highlighted important facets of these models such as metabolic pathways, basic kinetics of different metabolites, biomass growth, inhibition modeling and other additional features such as cell retention and immobilized cultures. Our review also covers the mathematical modeling of the downstream processing of ABE fermentation, i.e. recovery and purification of solvents through flash distillation, liquid-liquid extraction, and pervaporation. We believe that this review will be a useful source of information and analysis on mathematical models for ABE fermentation for both the appropriate scientific and engineering communities.
2015-09-30
Density from Data Collected by Slow-Moving Autonomous Ocean Vehicles , Investigating Key Aspects of Survey Design, Data Collection, and Data Analysis...TERM GOALS In this project, which started in April 2015, we focus on cetacean density estimation using autonomous underwater vehicles such as ocean...efforts. The major advantage of gliders and other autonomous vehicles over prior methods is their ability to provide both spatial and temporal coverage of
General aspects of effective field theories and few-body applications
Hammer, H -W
2016-01-01
Effective field theory provides a powerful framework to exploit a separation of scales in physical systems. In these lectures, we discuss some general aspects of effective field theories and their application to few-body physics. In particular, we consider an effective field theory for non-relativistic particles with resonant short-range interactions where certain parts of the interaction need to be treated nonperturbatively. As an application, we discuss the so-called pionless effective field theory for low-energy nuclear physics. The extension to include long-range interactions mediated by photon and pion-exchange is also addressed.
An Analysis of Students’ Communication during Group Work in Mathematics
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Pinelopi D. Vasileiadou
2013-06-01
Full Text Available Utilizing observation grid and interview study methologies, this research examines the ways in which students communicate with each other while working in a team during problem solving in mathematics. The study focuses primarily on the language used for communication. Results suggest that participants make assumptions to solve mathematical problems and justify their individual opinions, and cooperate and help each other, rarely asking for their teacher’s help, while using both the ordinary, and the mathematical spoken and written language. The interview indicates that students, although not experienced in undertaking group work, are able to readily identify its benefits and positive aspects.
An analysis of the mathematics school examination test quality
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Hadi Sutrisno
2016-11-01
Full Text Available This research aims to describe: (1 the quality of mathematics school examination test of the Junior High School for the academic year 2015/2016 in Kabupaten Bangkalan based on qualitative analysis of tests item, (2 the quality of mathematics school examination test of Junior High School for the academic year 2015/2016 in Kabupaten Bangkalan based on quantitative analysis of test items, and (3 the test equating on mathematics school examination test for the academic year of 2015/2016 of Junior High School in Kabupaten Bangkalan. A test is said to be quality if it fulfills validity, reliability, and it has good characteristic. A test is said to be equivalent to another if the test scores of one test can be exchanged with the scores of another test. The data is taken from school examination script accompanied with the answer sheets of students. Qualitative data analysis was conducted with the help of experts judgement. Quantitative data analysis was conducted with Classical Test Theory by Iteman and Item Response Theory by BilogMG. These programs are used to find out the test quality quantitatively. In order to analyze the equivalence between series of tests, item-characteristic curves were used. These curves were drawn by Geogebra. The research result shows: (1 qualitatively, the test plan quality of mathematics school examination test is quite good. Meanwhile, the school exam quality is quite good and not so good, (2 quantitatively, the school examination test quality is good, and (3 equating, based on the item-characteristic curves, the school examination tests is equal.
Mathematical aspects of the kriging applied on landslide in Halenkovice (Czech Republic
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Zůvala Robert
2016-06-01
Full Text Available Kriging is one of the geostatistical techniques for spatial data analysis that is usually used for a modelling of natural phenomena or a creation of digital elevation models. In this paper, we introduce kriging methods in the context of a landslide modelling in time. The proposed procedure, as well as most of the statistical methods, is designed for complete data sets, i.e. the observations at the beginning and the end of the study are available. In order to use all the information from the data and to avoid the loss of information after omitting observations with missing values, the algorithm for imputation of missing data values based on kriging techniques is proposed. The methodology was verified by the landslide modelling in Halenkovice, Czech Republic, during the period from June 2008 to March 2010. The obtained results showed a potential of kriging methods for the landslide modelling.
Mathematical aspects of the kriging applied on landslide in Halenkovice (Czech Republic)
Zůvala, Robert; Fišerová, Eva; Marek, Lukáš
2016-06-01
Kriging is one of the geostatistical techniques for spatial data analysis that is usually used for a modelling of natural phenomena or a creation of digital elevation models. In this paper, we introduce kriging methods in the context of a landslide modelling in time. The proposed procedure, as well as most of the statistical methods, is designed for complete data sets, i.e. the observations at the beginning and the end of the study are available. In order to use all the information from the data and to avoid the loss of information after omitting observations with missing values, the algorithm for imputation of missing data values based on kriging techniques is proposed. The methodology was verified by the landslide modelling in Halenkovice, Czech Republic, during the period from June 2008 to March 2010. The obtained results showed a potential of kriging methods for the landslide modelling.
Aeroelastic stability analysis of high aspect ratio aircraft wings
Banerjee, J. R.; Liu, X.; Kassem, H. I.
2014-01-01
Free vibration and flutter analyses of two types of high aspect ratio aircraft wings are presented. The wing is idealised as an assembly of bending-torsion coupled beams using the dynamic stiffness method leading to a nonlinear eigenvalue problem. This problem is solved using the Wattrick-Williams algorithm yielding natural frequencies and mode shapes. The flutter analysis is carried out using the normal mode method in conjunction with generalised coordinates and two-dimensional unsteady aero...
Hermann, Robert
1997-01-01
The aim of this research is to develop new mathematical methodology for the analysis of hybrid systems of the type involved in Air Traffic Control (ATC) problems. Two directions of investigation were initiated. The first used the methodology of nonlinear generalized functions, whose mathematical foundations were initiated by Colombeau and developed further by Oberguggenberger; it has been extended to apply to ordinary differential. Systems of the type encountered in control in joint work with the PI and M. Oberguggenberger. This involved a 'mixture' of 'continuous' and 'discrete' methodology. ATC clearly involves mixtures of two sorts of mathematical problems: (1) The 'continuous' dynamics of a standard control type described by ordinary differential equations (ODE) of the form: {dx/dt = f(x, u)} and (2) the discrete lattice dynamics involved of cellular automata. Most of the CA literature involves a discretization of a partial differential equation system of the type encountered in physics problems (e.g. fluid and gas problems). Both of these directions requires much thinking and new development of mathematical fundamentals before they may be utilized in the ATC work. Rather than consider CA as 'discretization' of PDE systems, I believe that the ATC applications will require a completely different and new mathematical methodology, a sort of discrete analogue of jet bundles and/or the sheaf-theoretic techniques to topologists. Here too, I have begun work on virtually 'virgin' mathematical ground (at least from an 'applied' point of view) which will require considerable preliminary work.
Mathematical analysis and calculation of molecular surfaces
Quan, Chaoyu; Stamm, Benjamin
2016-10-01
In this article we derive a complete characterization of the Solvent Excluded Surface (SES) for molecular systems including a complete characterization of singularities of the surface. The theory is based on an implicit representation of the SES, which, in turn, is based on the signed distance function to the Solvent Accessible Surface (SAS). All proofs are constructive so that the theory allows for efficient algorithms in order to compute the area of the SES and the volume of the SES-cavity, or to visualize the surface. Further, we propose to refine the notion of SAS and SES in order to take inner holes in a solute molecule into account or not.
Pugh, Charles C
2015-01-01
Based on an honors course taught by the author at UC Berkeley, this introduction to undergraduate real analysis gives a different emphasis by stressing the importance of pictures and hard problems. Topics include: a natural construction of the real numbers, four-dimensional visualization, basic point-set topology, function spaces, multivariable calculus via differential forms (leading to a simple proof of the Brouwer Fixed Point Theorem), and a pictorial treatment of Lebesgue theory. Over 150 detailed illustrations elucidate abstract concepts and salient points in proofs. The exposition is informal and relaxed, with many helpful asides, examples, some jokes, and occasional comments from mathematicians, such as Littlewood, Dieudonné, and Osserman. This book thus succeeds in being more comprehensive, more comprehensible, and more enjoyable, than standard introductions to analysis. New to the second edition of Real Mathematical Analysis is a presentation of Lebesgue integration done almost entirely using the un...
Qualitative mathematical analysis of the Richards equation
Gilding, B.H.
1991-01-01
The Richards equation is widely used as a model for the flow of water in unsaturated soils. For modelling one-dimensional flow in a homogeneous soil, this equation can be cast in the form of a specific nonlinear partial differential equation with a time derivative and one spatial derivative. This
Mathematical Analysis and Simulation of Crop Micrometeorology
Chen, J.
1984-01-01
In crop micrometeorology the transfer of radiation, momentum, heat and mass to or from a crop canopy is studied. Simulation models for these processes do exist but are not easy to handle because of their complexity and the long computing time they need. Moreover, up to now such models can only be ru
A mathematical analysis of second messenger compartmentalization.
Chen, Wen; Levine, Herbert; Rappel, Wouter-Jan
2008-12-10
Intracellular compartmentalization of second messengers can lead to microdomains of elevated concentration that are thought to be involved in ensuring signaling specificity. Most experimental evidence for this compartmentalization involves the second messenger adenosine monophosphate (cAMP), which is degraded by phosphodiesterases (PDEs). One possible way of creating these compartments, supported by recent experiments, is to spatially separate the source of cAMP from regions of elevated PDE concentration. To quantify this possibility, we study here a simplified geometry in two dimensions (2D) and in three dimensions (3D), containing a cAMP point source and regions with different degradation constants. Using the symmetry of our geometry, we are able to derive steady state solutions for the cAMP concentration as a function of the system parameters. Furthermore, we show, using analytics as well as direct numerical simulations, that for physiologically relevant time scales the steady state solution has been reached. Our results indicate that elevating the degradation constant throughout the cell, except for a small microdomain surrounding the source, requires an unphysiologically high cellular PDE concentration. On the other hand, a tight spatial relationship of localized PDEs with the cAMP source can result in functional microdomains while maintaining a physiologically plausible cellular PDE concentration.
Mathematical analysis of electromigration dispersion fronts
Christov, Ivan C.
2016-11-01
It is of interest to understand traveling electromigration wave phenomena, such as isotachophoretic boundaries, because of their applications in electrophoretic separation methods. To this end, we construct exact solutions to an unusual nonlinear advection-diffusion equation arising in the study of Taylor-Aris (also known as shear) dispersion due to electroosmotic flow during electromigration in a capillary. An exact reduction to a Darboux equation is found under a traveling-wave anzats. The equilibria of this ordinary differential equation are analyzed, showing that their stability is determined solely by the (dimensionless) wave speed without regard to any (dimensionless) physical parameters. Integral curves, connecting the appropriate equilibria of the Darboux equation that governs traveling waves, are constructed, which in turn are shown to be asymmetric kink solutions (i.e., non-Taylor shocks). Furthermore, it is shown that the governing Darboux equation exhibits bistability, which leads to two coexisting non-negative kink solutions for (dimensionless) wave speeds greater than unity.
Mathematical analysis of the honeybee waggle dance.
Okada, R; Ikeno, H; Kimura, T; Ohashi, Mizue; Aonuma, H; Ito, E
2012-01-01
A honeybee informs her nestmates of the location of a flower by doing a waggle dance. The waggle dance encodes both the direction of and distance to the flower from the hive. To reveal how the waggle dance benefits the colony, we created a Markov model of bee foraging behavior and performed simulation experiments by incorporating the biological parameters that we obtained from our own observations of real bees as well as from the literature. When two feeders were each placed 400 m away from the hive in different directions, a virtual colony in which honeybees danced and correctly transferred information (a normal, real bee colony) made significantly greater numbers of successful visits to the feeders compared to a colony with inaccurate information transfer. Howerer, when five feeders were each located 400 m from the hive, the inaccurate information transfer colony performed better than the normal colony. These results suggest that dancing's ability to communicate accurate information depends on the number of feeders. Furthermore, because non-dancing colonies always made significantly fewer visits than those two colonies, we concluded that dancing behavior is beneficial for hives' ability to visit food sources.
Mathematical Analysis of Algorithms within Mana
2014-06-01
attrition rate coefficients to describe a battle between two forces. Lanchester’s idea was to utilize differential calculus to solve the equations that...H. VECTOR ARITHMETIC REVIEW This section utilizes Stewart’s calculus work for the review of vector addition and scalar multiplication of...Introduction to Cryptography with Coding Theory, 2nd ed. Upper Saddle River, NJ: Pearson Education, 2006, ch. 2, sec. 10, pp. 41–43. [10] J
Methods of Approximation Theory in Complex Analysis and Mathematical Physics
Saff, Edward
1993-01-01
The book incorporates research papers and surveys written by participants ofan International Scientific Programme on Approximation Theory jointly supervised by Institute for Constructive Mathematics of University of South Florida at Tampa, USA and the Euler International Mathematical Instituteat St. Petersburg, Russia. The aim of the Programme was to present new developments in Constructive Approximation Theory. The topics of the papers are: asymptotic behaviour of orthogonal polynomials, rational approximation of classical functions, quadrature formulas, theory of n-widths, nonlinear approximation in Hardy algebras,numerical results on best polynomial approximations, wavelet analysis. FROM THE CONTENTS: E.A. Rakhmanov: Strong asymptotics for orthogonal polynomials associated with exponential weights on R.- A.L. Levin, E.B. Saff: Exact Convergence Rates for Best Lp Rational Approximation to the Signum Function and for Optimal Quadrature in Hp.- H. Stahl: Uniform Rational Approximation of x .- M. Rahman, S.K. ...
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Trude Nilsen
2013-10-01
Full Text Available As students advance in their learning of physics over the course of their education, the requirement of mathematical applications in physics-related tasks increases, especially so in upper secondary school and in higher education. Yet there is little empirical work (particularly large-scale or longitudinal on the application of mathematics in physics education compared with the research related to the conceptual knowledge of physics. In order to clarify the nature of mathematics in physics education, we developed a theoretical framework for mathematical competencies pertinent to various physics tasks based on theoretical frameworks from mathematics and physics education. We used this synthesis of frameworks as a basis to create a model for physics competence. The framework also served as a tool for analyzing and categorizing trend items from the international large-scale survey, TIMSS Advanced 1995 and 2008. TIMSS Advanced assessed students in upper secondary school with special preparation in advanced physics and mathematics. We then investigated the changes in achievements on these categorized items across time for nations who participated in both surveys. The results from our analysis indicate that students whose overall physics achievement declined struggled the most with items requiring mathematics, especially items requiring them to handle symbols, such as manipulating equations. This finding suggests the importance of collaboration between mathematics and physics education as well as the importance of traditional algebra for physics education.
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…
Mathematical modeling of isotope labeling experiments for metabolic flux analysis.
Nargund, Shilpa; Sriram, Ganesh
2014-01-01
Isotope labeling experiments (ILEs) offer a powerful methodology to perform metabolic flux analysis. However, the task of interpreting data from these experiments to evaluate flux values requires significant mathematical modeling skills. Toward this, this chapter provides background information and examples to enable the reader to (1) model metabolic networks, (2) simulate ILEs, and (3) understand the optimization and statistical methods commonly used for flux evaluation. A compartmentalized model of plant glycolysis and pentose phosphate pathway illustrates the reconstruction of a typical metabolic network, whereas a simpler example network illustrates the underlying metabolite and isotopomer balancing techniques. We also discuss the salient features of commonly used flux estimation software 13CFLUX2, Metran, NMR2Flux+, FiatFlux, and OpenFLUX. Furthermore, we briefly discuss methods to improve flux estimates. A graphical checklist at the end of the chapter provides a reader a quick reference to the mathematical modeling concepts and resources.
Error Analysis in Mathematics Education.
Rittner, Max
1982-01-01
The article reviews the development of mathematics error analysis as a means of diagnosing students' cognitive reasoning. Errors specific to addition, subtraction, multiplication, and division are described, and suggestions for remediation are provided. (CL)
Three dimensional mathematical model of tooth for finite element analysis
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Puškar Tatjana
2010-01-01
Full Text Available Introduction. The mathematical model of the abutment tooth is the starting point of the finite element analysis of stress and deformation of dental structures. The simplest and easiest way is to form a model according to the literature data of dimensions and morphological characteristics of teeth. Our method is based on forming 3D models using standard geometrical forms (objects in programmes for solid modeling. Objective. Forming the mathematical model of abutment of the second upper premolar for finite element analysis of stress and deformation of dental structures. Methods. The abutment tooth has a form of a complex geometric object. It is suitable for modeling in programs for solid modeling SolidWorks. After analyzing the literature data about the morphological characteristics of teeth, we started the modeling dividing the tooth (complex geometric body into simple geometric bodies (cylinder, cone, pyramid,.... Connecting simple geometric bodies together or substricting bodies from the basic body, we formed complex geometric body, tooth. The model is then transferred into Abaqus, a computational programme for finite element analysis. Transferring the data was done by standard file format for transferring 3D models ACIS SAT. Results. Using the programme for solid modeling SolidWorks, we developed three models of abutment of the second maxillary premolar: the model of the intact abutment, the model of the endodontically treated tooth with two remaining cavity walls and the model of the endodontically treated tooth with two remaining walls and inserted post. Conclusion Mathematical models of the abutment made according to the literature data are very similar with the real abutment and the simplifications are minimal. These models enable calculations of stress and deformation of the dental structures. The finite element analysis provides useful information in understanding biomechanical problems and gives guidance for clinical research.
[Three dimensional mathematical model of tooth for finite element analysis].
Puskar, Tatjana; Vasiljević, Darko; Marković, Dubravka; Jevremović, Danimir; Pantelić, Dejan; Savić-Sević, Svetlana; Murić, Branka
2010-01-01
The mathematical model of the abutment tooth is the starting point of the finite element analysis of stress and deformation of dental structures. The simplest and easiest way is to form a model according to the literature data of dimensions and morphological characteristics of teeth. Our method is based on forming 3D models using standard geometrical forms (objects) in programmes for solid modeling. Forming the mathematical model of abutment of the second upper premolar for finite element analysis of stress and deformation of dental structures. The abutment tooth has a form of a complex geometric object. It is suitable for modeling in programs for solid modeling SolidWorks. After analysing the literature data about the morphological characteristics of teeth, we started the modeling dividing the tooth (complex geometric body) into simple geometric bodies (cylinder, cone, pyramid,...). Connecting simple geometric bodies together or substricting bodies from the basic body, we formed complex geometric body, tooth. The model is then transferred into Abaqus, a computational programme for finite element analysis. Transferring the data was done by standard file format for transferring 3D models ACIS SAT. Using the programme for solid modeling SolidWorks, we developed three models of abutment of the second maxillary premolar: the model of the intact abutment, the model of the endodontically treated tooth with two remaining cavity walls and the model of the endodontically treated tooth with two remaining walls and inserted post. Mathematical models of the abutment made according to the literature data are very similar with the real abutment and the simplifications are minimal. These models enable calculations of stress and deformation of the dental structures. The finite element analysis provides useful information in understanding biomechanical problems and gives guidance for clinical research.
Proceedings of the NASA Symposium on Mathematical Pattern Recognition and Image Analysis
Guseman, L. F., Jr.
1983-01-01
The application of mathematical and statistical analyses techniques to imagery obtained by remote sensors is described by Principal Investigators. Scene-to-map registration, geometric rectification, and image matching are among the pattern recognition aspects discussed.
Mathematical analysis of intermittent gas injection model in oil production
Tasmi, Silvya, D. R.; Pudjo, S.; Leksono, M.; Edy, S.
2016-02-01
Intermittent gas injection is a method to help oil production process. Gas is injected through choke in surface and then gas into tubing. Gas forms three areas in tubing: gas column area, film area and slug area. Gas column is used to propel slug area until surface. A mathematical model of intermittent gas injection is developed in gas column area, film area and slug area. Model is expanding based on mass and momentum conservation. Using assume film thickness constant in tubing, model has been developed by Tasmi et. al. [14]. Model consists of 10 ordinary differential equations. In this paper, assumption of pressure in gas column is uniform. Model consist of 9 ordinary differential equations. Connection of several variables can be obtained from this model. Therefore, dynamics of all variables that affect to intermittent gas lift process can be seen from four equations. To study the behavior of variables can be analyzed numerically and mathematically. In this paper, simple mathematically analysis approach is used to study behavior of the variables. Variables that affect to intermittent gas injection are pressure in upstream valve and in gas column. Pressure in upstream valve will decrease when gas mass in valve greater than gas mass in choke. Dynamic of the pressure in the gas column will decrease and increase depending on pressure in upstream valve.
Mathematical Modeling and Analysis of Multirobot Cooperative Hunting Behaviors
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Yong Song
2015-01-01
Full Text Available This paper presents a mathematical model of multirobot cooperative hunting behavior. Multiple robots try to search for and surround a prey. When a robot detects a prey it forms a following team. When another “searching” robot detects the same prey, the robots form a new following team. Until four robots have detected the same prey, the prey disappears from the simulation and the robots return to searching for other prey. If a following team fails to be joined by another robot within a certain time limit the team is disbanded and the robots return to searching state. The mathematical model is formulated by a set of rate equations. The evolution of robot collective hunting behaviors represents the transition between different states of robots. The complex collective hunting behavior emerges through local interaction. The paper presents numerical solutions to normalized versions of the model equations and provides both a steady state and a collaboration ratio analysis. The value of the delay time is shown through mathematical modeling to be a strong factor in the performance of the system as well as the relative numbers of the searching robots and the prey.
[Some basic aspects in statistical analysis of visual acuity data].
Ren, Ze-Qin
2007-06-01
All visual acuity charts used currently have their own shortcomings. Therefore, it is difficult for ophthalmologists to evaluate visual acuity data. Many problems present in the use of statistical methods for handling visual acuity data in clinical research. The quantitative relationship between visual acuity and visual angle varied in different visual acuity charts. The type of visual acuity and visual angle are different from each other. Therefore, different statistical methods should be used for different data sources. A correct understanding and analysis of visual acuity data could be obtained only after the elucidation of these aspects.
Peng, Peng; Namkung, Jessica; Barnes, Marcia; Sun, Congying
2016-01-01
The purpose of this meta-analysis was to determine the relation between mathematics and working memory (WM) and to identify possible moderators of this relation including domains of WM, types of mathematics skills, and sample type. A meta-analysis of 110 studies with 829 effect sizes found a significant medium correlation of mathematics and WM, r…
Peng, Peng; Namkung, Jessica; Barnes, Marcia; Sun, Congying
2016-01-01
The purpose of this meta-analysis was to determine the relation between mathematics and working memory (WM) and to identify possible moderators of this relation including domains of WM, types of mathematics skills, and sample type. A meta-analysis of 110 studies with 829 effect sizes found a significant medium correlation of mathematics and WM, r…
Practical Aspects of Drug Calculations. Mathematics Education Centre. Report No. 24.
Sullivan, Peter; Clarkson, P., Ed.
Concern has been expressed in recent years about the accuracy of medication administered by nurses in Papua New Guinean hospitals. Attention has been focused on the calculation of the drug dosages. This paper discusses the processes involved in the administration of medication, and reports on a study to evaluate the competence of student nurses at…
Jones, Keith
2000-01-01
A sociocultural analysis suggests that pedagogical artifacts employed in the teaching and learning of mathematics both enable and constrain learning. This paper summarises three classroom studies of mathematics learning that have utilised a sociocultural approach. Each of the studies indicates how insight can be gained into the ways in which students attempt to make sense of the mathematics they encounter.
Instability of protein drops via applied electric field: mathematical and experimental aspects.
Penkova, Anita; Mladenov, Ivaïlo M
2009-04-01
Drops (5-15 microL) consisting of a protein solution readily crystallize and could provide an opportunity for a simultaneous examination of their thermodynamic and kinetic properties at various sizes. These drops experienced different pressures and therefore different surface tensions. Starting from the expression for the interface traction between protein fluid and silicon medium (with different dielectric constants), we have derived an equation accounting the influence of the electric field strength on the geometry of a protein drop. If the field strength increases, the lysozyme drop between two electrodes elongates and some crystals nucleate on the cathode side. In this situation numerous factors besides the intensity of the electric field--such as the solution composition, the charge and size of the protein molecule, the purity of the protein substance, and the consistency of bubbles of water--can have a significant effect on the crystallization rate and location.
Mathematical Aspects of Quantum Systems with a Pseudo-Hermitian Hamiltonian
Bebiano, N.; da Providência, J.; da Providência, J. P.
2016-04-01
A non-self-adjoint bosonic Hamiltonian H possessing real eigenvalues is investigated. It is shown that the operator can be diagonalized by making use of pseudo-bosonic operators. The biorthogonal sets of eigenvectors for the Hamiltonian and its adjoint are explicitly constructed. The positive definite operator which connects both sets of eigenvectors is also given. The dynamics of the model is briefly analyzed.
Hempel, Rainer
2011-01-01
We discuss two types of defects in two-dimensional lattices, namely (1) translational dislocations and (2) defects produced by a rotation of the lattice in a half-space. For Lipschitz-continuous and $\\Z^2$-periodic potentials, we first show that translational dislocations produce spectrum inside the gaps of the periodic problem; we also give estimates for the (integrated) density of the associated surface states. We then study lattices with a small angle defect where we find that the gaps of the periodic problem fill with spectrum as the defect angle goes to zero. To introduce our methods, we begin with the study of dislocation problems on the real line and on an infinite strip. Finally, we consider examples of muffin tin type. Our overview refers to results in [HK1, HK2].
Background and Mathematical Analysis of Diffusion MRI Methods.
Ozcan, Alpay; Wong, Kenneth H; Larson-Prior, Linda; Cho, Zang-Hee; Mun, Seong K
2012-03-01
The addition of a pair of magnetic field gradient pulses had initially provided the measurement of spin motion with nuclear magnetic resonance (NMR) techniques. In the adaptation of DW-NMR techniques to magnetic resonance imaging (MRI), the taxonomy of mathematical models is divided in two categories: model matching and spectral methods. In this review, the methods are summarized starting from early diffusion weighted (DW) NMR models followed up with their adaptation to DW MRI. Finally, a newly introduced Fourier analysis based unifying theory, so-called Complete Fourier Direct MRI, is included to explain the mechanisms of existing methods.
Oldfield, Christine
1996-01-01
Describes aspects of learning the language of mathematics including vocabulary and grammar, the origins of the vocabulary, the pronunciation problem, and translation of English phrases and sentences into mathematical language accompanied by conceptual understanding of the process being described. Gives suggestions for teachers in class and…
Directory of Open Access Journals (Sweden)
Waleed
2009-01-01
Full Text Available Problem statement: Generalization feature enhancement of neural networks, especially feed forward structural model has limited progress. The major reason behind such limitation is attributed to the principal definition and the inability to interpret it into convenient structure. Traditional schemes, unfortunately have regarded generalization as an innate outcome of the simple association, referred to by Pavlov and had been modeled by piaget as the basis of assimilating conduct. Approach: A new generalization approach based on the addition of a supportive layer to the traditional neural network scheme (atomic scheme was presented. This approach extended the signal propagation of the whole net in order to generate the output in two modes, one deals with the required output of trained patterns with predefined settings, while the other tolerates output generation dynamically with tuning capability for any newly applied input. Results: Experiments and analysis showed that the new approach is not only simpler and easier, but also is very effective as the proportions promoting the generalization ability of neural networks have reached over 90% for some cases. Conclusion: Expanding neuron as the generalization essential construction denoted the accommodating capabilities involving all the innate structures in conjugation with Intelligence abilities and with the needs of further advanced learning phases. Cogent results were attained in comparison with that of the traditional schemes.
Nonlinear mathematical modeling and sensitivity analysis of hydraulic drive unit
Kong, Xiangdong; Yu, Bin; Quan, Lingxiao; Ba, Kaixian; Wu, Liujie
2015-09-01
The previous sensitivity analysis researches are not accurate enough and also have the limited reference value, because those mathematical models are relatively simple and the change of the load and the initial displacement changes of the piston are ignored, even experiment verification is not conducted. Therefore, in view of deficiencies above, a nonlinear mathematical model is established in this paper, including dynamic characteristics of servo valve, nonlinear characteristics of pressure-flow, initial displacement of servo cylinder piston and friction nonlinearity. The transfer function block diagram is built for the hydraulic drive unit closed loop position control, as well as the state equations. Through deriving the time-varying coefficient items matrix and time-varying free items matrix of sensitivity equations respectively, the expression of sensitivity equations based on the nonlinear mathematical model are obtained. According to structure parameters of hydraulic drive unit, working parameters, fluid transmission characteristics and measured friction-velocity curves, the simulation analysis of hydraulic drive unit is completed on the MATLAB/Simulink simulation platform with the displacement step 2 mm, 5 mm and 10 mm, respectively. The simulation results indicate that the developed nonlinear mathematical model is sufficient by comparing the characteristic curves of experimental step response and simulation step response under different constant load. Then, the sensitivity function time-history curves of seventeen parameters are obtained, basing on each state vector time-history curve of step response characteristic. The maximum value of displacement variation percentage and the sum of displacement variation absolute values in the sampling time are both taken as sensitivity indexes. The sensitivity indexes values above are calculated and shown visually in histograms under different working conditions, and change rules are analyzed. Then the sensitivity
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.
Mathematical analysis of dynamic spread of Pine Wilt disease.
Dimitrijevic, D D; Bacic, J
2013-01-01
Since its detection in Portugal in 1999, the pinewood nematode Bursaphelenchus xylophilus (Steiner and Buhrer), a causal agent of Pine Wilt Disease, represents a threat to European forestry. Significant amount of money has been spent on its monitoring and eradication. This paper presents mathematical analysis of spread of pine wilt disease using a set of partial differential equations with space (longitude and latitude) and time as parameters of estimated spread of disease. This methodology can be used to evaluate risk of various assumed entry points of disease and make defense plans in advance. In case of an already existing outbreak, it can be used to draw optimal line of defense and plan removal of trees. Optimization constraints are economic loss of removal of susceptible trees as well as budgetary constraints of workforce cost.
Directory of Open Access Journals (Sweden)
Yu. V. Lobzin
2016-01-01
Full Text Available Generalized meningococcal infection belongs to the group of diseases with a high risk of initiation of life-threatening conditions and death outcomes. There was carried out a retrospective analysis of clinical and epidemiological features of generalized meningococcal infections in children and adolescents of Saint Petersburg in 1995–2014 on the basis of the analysis of 884 medical records of the patients hospitalized at Scientific Research Institute of Children’s Infections. With general prevalence of the children of the first years of life among the patients, there has been revealed the tendency to reduction in the portion of children of the first year of life from 41,4% in 1995 to 22,2% by 2014, and the increase in the number of patients of 1–3 years old from 19,3–30,5% in 1995–1996 to 46,4–46,4% in 2013–2014. Among the number of etiologically identified cases (59,4% the majority of them has been caused by serogroup B meningococcus (58,5%, in 24,2% – by serogroup C meningococcus, in 11,2% – by serogroup A meningococcus, and in 6,1% – by rare (W135/Y and unspecified strains N.meningitidis. Within the recent years there has been identified the tendency of rate growth concerning the diseases caused by serogroup C meningococci, remarkable for a severe course and high rate of death cases. Total death indicator for the investigated period has averaged 4,2%, with the variability from 0 to 12,5% for different years.
Quantization, PDEs, and geometry the interplay of analysis and mathematical physics
Bauer, Wolfram; Witt, Ingo
2016-01-01
This book presents four survey articles on different topics in mathematical analysis that are closely linked to concepts and applications in physics. Specifically, it discusses global aspects of elliptic PDEs, Berezin-Toeplitz quantization, the stability of solitary waves, and sub-Riemannian geometry. The contributions are based on lectures given by distinguished experts at a summer school in Göttingen. The authors explain fundamental concepts and ideas and present them clearly. Starting from basic notions, these course notes take the reader to the point of current research, highlighting new challenges and addressing unsolved problems at the interface between mathematics and physics. All contributions are of interest to researchers in the respective fields, but they are also accessible to graduate students.
A Mathematical Analysis of Air Traffic Priority Rules
Nakawicz, Anthony J.; Munoz, Cesar A.; Maddalon, Jeffrey M.
2012-01-01
This paper analyzes priority rules, such as those in Part 91.113 of the Federal Aviation Regulations. Such rules determine which of two aircraft should maneuver in a given conflict scenario. While the rules in 91.113 are well accepted, other concepts of operation for NextGen, such as self separation, may allow for different priority rules. A mathematical framework is presented that can be used to analyze a general set of priority rules and enables proofs of important properties. Specific properties considered in this paper include safety, effectiveness, and stability. A set of rules is said to be safe if it ensures that it is never the case that both aircraft have priority. They are effective if exactly one aircraft has priority in every situation. Finally, a set of rules is called stable if it produces compatible results even under small changes to input data.
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.
The Use of Video Analysis and the Knowledge Quartet in Mathematics Teacher Education Programmes
Liston, Miriam
2015-01-01
This study investigates the potential of video analysis and a mathematical knowledge for teaching framework, the Knowledge Quartet (KQ), in mathematics teacher education programmes. It reports on the effectiveness of these tools in analysing and supporting secondary level pre-service mathematics teachers' subject matter knowledge and pedagogical…
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...
Generalized functions, volume 2 spaces of fundamental and generalized functions
Gel′fand, I M
2016-01-01
The first systematic theory of generalized functions (also known as distributions) was created in the early 1950s, although some aspects were developed much earlier, most notably in the definition of the Green's function in mathematics and in the work of Paul Dirac on quantum electrodynamics in physics. The six-volume collection, Generalized Functions, written by I. M. Gel′fand and co-authors and published in Russian between 1958 and 1966, gives an introduction to generalized functions and presents various applications to analysis, PDE, stochastic processes, and representation theory. Volume 2
Andasari, Vivi; Gerisch, Alf; Lolas, Georgios; South, Andrew P; Chaplain, Mark A J
2011-07-01
The ability of cancer cells to break out of tissue compartments and invade locally gives solid tumours a defining deadly characteristic. One of the first steps of invasion is the remodelling of the surrounding tissue or extracellular matrix (ECM) and a major part of this process is the over-expression of proteolytic enzymes, such as the urokinase-type plasminogen activator (uPA) and matrix metalloproteinases (MMPs), by the cancer cells to break down ECM proteins. Degradation of the matrix enables the cancer cells to migrate through the tissue and subsequently to spread to secondary sites in the body, a process known as metastasis. In this paper we undertake an analysis of a mathematical model of cancer cell invasion of tissue, or ECM, which focuses on the role of the urokinase plasminogen activation system. The model consists of a system of five reaction-diffusion-taxis partial differential equations describing the interactions between cancer cells, uPA, uPA inhibitors, plasmin and the host tissue. Cancer cells react chemotactically and haptotactically to the spatio-temporal effects of the uPA system. The results obtained from computational simulations carried out on the model equations produce dynamic heterogeneous spatio-temporal solutions and using linear stability analysis we show that this is caused by a taxis-driven instability of a spatially homogeneous steady-state. Finally we consider the biological implications of the model results, draw parallels with clinical samples and laboratory based models of cancer cell invasion using three-dimensional invasion assay, and go on to discuss future development of the model.
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.
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…
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)
Zorich, Vladimir A
2016-01-01
This second English edition of a very popular two-volume work presents a thorough first course in analysis, leading from real numbers to such advanced topics as differential forms on manifolds; asymptotic methods; Fourier, Laplace, and Legendre transforms; elliptic functions; and distributions. Especially notable in this course are the clearly expressed orientation toward the natural sciences and the informal exploration of the essence and the roots of the basic concepts and theorems of calculus. Clarity of exposition is matched by a wealth of instructive exercises, problems, and fresh applications to areas seldom touched on in textbooks on real analysis. The main difference between the second and first English editions is the addition of a series of appendices to each volume. There are six of them in the first volume and five in the second. The subjects of these appendices are diverse. They are meant to be useful to both students (in mathematics and physics) and teachers, who may be motivated by different go...
Lectures on the mathematics of finance
Karatzas, Ioannis
1996-01-01
In this text, the author discusses the main aspects of mathematical finance. These include arbitrage, hedging and pricing of contingent claims, portfolio optimization, incomplete and/or constrained markets, equilibrium, and transaction costs. The book outlines advances made possible during the last fifteen years due to the methodologies of stochastic analysis and control. Readers are presented with current research, and open problems are suggested. This tutorial survey of the rapidly expanding field of mathematical finance is addressed primarily to graduate students in mathematics. Familiarity is assumed with stochastic analysis and parabolic partial differential equations. The text makes significant use of students' mathematical skills, but always in connection with interesting applied problems.
Mathematical analysis of mammary ducts in lactating human breast.
Mortazavi, S Negin; Geddes, Donna; Hassiotou, Foteini; Hassanipour, Fatemeh
2014-01-01
This work studies a simple model for milk transport through lactating human breast ducts, and describes mathematically the mass transfer from alveolar sacs through the mammary ducts to the nipple. In this model both the phenomena of diffusion in the sacs and conventional flow in ducts have been considered. The ensuing analysis reveals that there is an optimal range of bifurcation numbers leading to the easiest milk flow based on the minimum flow resistance. This model formulates certain difficult-to-measure values like diameter of the alveolar sacs, and the total length of the milk path as a function of easy-to-measure properties such as milk fluid properties and macroscopic measurements of the breast. Alveolar dimensions from breast tissues of six lactating women are measured and reported in this paper. The theoretically calculated alveoli diameters for optimum milk flow (as a function of bifurcation numbers) show excellent match with our biological data on alveolar dimensions. Also, the mathematical model indicates that for minimum milk flow resistance the glandular tissue must be within a short distance from the base of the nipple, an observation that matches well with the latest anatomical and physiological research.
[Representation and mathematical analysis of human crystalline lens].
Tălu, Stefan; Giovanzana, Stefano; Tălu, Mihai
2011-01-01
The surface of human crystalline lens can be described and analyzed using mathematical models based on parametric representations, used in biomechanical studies and 3D solid modeling of the lens. The mathematical models used in lens biomechanics allow the study and the behavior of crystalline lens on variables and complex dynamic loads. Also, the lens biomechanics has the potential to improve the results in the development of intraocular lenses and cataract surgery. The paper presents the most representative mathematical models currently used for the modeling of human crystalline lens, both optically and biomechanically.
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Liras Antonio
2010-12-01
Full Text Available Abstract There is much to be investigated about the specific characteristics of stem cells and about the efficacy and safety of the new drugs based on this type of cells, both embryonic as adult stem cells, for several therapeutic indications (cardiovascular and ischemic diseases, diabetes, hematopoietic diseases, liver diseases. Along with recent progress in transference of nuclei from human somatic cells, as well as iPSC technology, has allowed availability of lineages of all three germ layers genetically identical to those of the donor patient, which permits safe transplantation of organ-tissue-specific adult stem cells with no immune rejection. The main objective is the need for expansion of stem cell characteristics to maximize stem cell efficacy (i.e. the proper selection of a stem cell and the efficacy (maximum effect and safety of stem cell derived drugs. Other considerations to take into account in cell therapy will be the suitability of infrastructure and technical staff, biomaterials, production costs, biobanks, biosecurity, and the biotechnological industry. The general objectives in the area of stem cell research in the next few years, are related to identification of therapeutic targets and potential therapeutic tests, studies of cell differentiation and physiological mechanisms, culture conditions of pluripotent stem cells and efficacy and safety tests for stem cell-based drugs or procedures to be performed in both animal and human models in the corresponding clinical trials. A regulatory framework will be required to ensure patient accessibility to products and governmental assistance for their regulation and control. Bioethical aspects will be required related to the scientific and therapeutic relevance and cost of cryopreservation over time, but specially with respect to embryos which may ultimately be used for scientific uses of research as source of embryonic stem cells, in which case the bioethical conflict may be further
Three Aspects as Considered of Discourse Analysis:World,Language and Participants
Institute of Scientific and Technical Information of China (English)
朱思亲
2014-01-01
from the three aspects,discourse analysis and the world,discourse analysis and language,and discourse analysis and participants,the author discusses the discourse analysis applied in the paper Effect of First Language on the Use of English Discourse Markers by L1 Chinese Speakers of English.All of these three aspects interact with discourse analysis.Understanding the discourse analysis from the three aspects above will help to read a paper using the discourse analysis.
Three Aspects as Considered of Discourse Analysis:World,Language and Participants
Institute of Scientific and Technical Information of China (English)
朱思亲
2014-01-01
from the three aspects, discourse analysis and the world, discourse analysis and language, and discourse analysis and participants, the author discusses the discourse analysis applied in the paper Effect of First Language on the Use of English Discourse Markers by L1 Chinese Speakers of English. All of these three aspects interact with discourse analysis. Understanding the discourse analysis from the three aspects above will help to read a paper using the discourse analysis.
Interrelation of GDP and pension capital: Mathematical and econometrical analysis
Nepp, A. N.; Dolgodvorov, A. D.
2016-12-01
This article is a mathematicalanalysis of the relationship between GDP and the development of funded pension systems. For this purpose, a mathematical formula was derived from the macro-economic GDP, proportional to the level of income and consumption for the dependence of GDP on the level of pension payments, the value of pension savings and the structure of compulsory contributions to the pension fund allocated to the distribution and accumulative pension system. A derivation of the equation proves the linear relationship of GDP and the share of pension contributions channeled to the funded pension system. Thus, the macroeconomic indicator with the larger negative impact on GDP was proven to be the elimination of the compulsory funded pension system. Based on the econometric analysis, the positive effect of the distributive pension system was proven on macroeconomic parameters.
An educational activity for middle school teachers: analysis of Invalsi mathematics tests
Directory of Open Access Journals (Sweden)
Francesca Martignone
2016-04-01
Full Text Available This paper shows how the analysis of items of Italian national standardized mathematics tests (Invalsi can become a means to develop teacher education programs for mathematics middle school teachers. Through the comparison among peers and the teacher educator, the teachers can develop new lenses to look at the Invalsi mathematics tests using interpretative tools from research in mathematics education. In particular, in the educational activities that will be described, the teachers share a structured approach in the development of an a priori analysis of mathematics problems that takes into account institutional, epistemological, cognitive, and didactic aspects. These educational activities foster the development and sharing of knowledge and skills that can be identified as specialized knowledge for teaching. Un’attività di formazione per insegnanti di scuola secondaria di primo grado: analisi di prove Invalsi di matematicaQuesto articolo mostra come l’analisi di quesiti delle prove Invalsi di matematica possa diventare un mezzo per sviluppare attività di formazione per insegnanti di matematica di scuola secondaria di primo grado. Attraverso il confronto tra pari e con il docente formatore, gli insegnanti possono acquisire nuove chiavi di lettura delle prove Invalsi di matematica facendo propri alcuni strumenti interpretativi e di analisi provenienti dalla ricerca in didattica della matematica. In particolare, nelle attività di formazione che saranno descritte, gli insegnanti condividono un approccio strutturato nello sviluppo di un’analisi a priori di quesiti di matematica che tiene conto dell’intreccio di aspetti istituzionali, epistemologici, cognitivi e didattici. Queste attività di formazione hanno favorito lo sviluppo e la condivisione di conoscenze e abilità che possono essere identificate come conoscenze specialistiche per l’insegnamento.
Analysis of a mathematical model of syntrophic bacteria in a chemostat
Sari, Tewfik; Harmand, Jérôme
2011-01-01
A mathematical model involving a syntrophic relationship between two populations of bacteria in a continuous culture is proposed. A detailed qualitative analysis is carried out. The local and global stability analysis of the equilibria are performed. We demonstrate, under general assumptions of monotonicity, relevant from an applied point of view, the asymptotic stability of the positive equilibrium point which corresponds to the coexistence of the two bacteria. A syntrophic relationship in the anaerobic digestion process is proposed as a real candidate for this model.
Analysis of quantitative pore features based on mathematical morphology
Institute of Scientific and Technical Information of China (English)
QI Heng-nian; CHEN Feng-nong; WANG Hang-jun
2008-01-01
Wood identification is a basic technique of wood science and industry. Pore features are among the most important identification features for hardwoods. We have used a method based on an analysis of quantitative pore feature, which differs from traditional qualitative methods. We applies mathematical morphology methods such as dilation and erosion, open and close transformation of wood cross-sections, image repairing, noise filtering and edge detection to segment the pores from their background. Then the mean square errors (MSE) of pores were computed to describe the distribution of pores. Our experiment shows that it is easy to classift the pore features into three basic types, just as in traditional qualitative methods, but with the use of MSE of pores. This quantitative method improves wood identification considerably.
General aspects of two-component regulatory circuits in bacteria: Domains, signals and roles.
Padilla-Vaca, Felipe; Mondragón-Jaimes, Verónica; Franco, Bernardo
2016-08-09
All living organisms are subject to changing environments, which must be sensed in order to respond swiftly and efficiently. Two-component systems (TCS) are signal transduction regulatory circuits based typically on a membrane bound sensor kinase and a cytoplasmic response regulator, that is activated through a histidine to aspartate phosphorelay reactions. Activated response regulator acts usually as a transcription factor. The best known examples were identified in bacteria, but they are also found in fungi, algae and plants. Thus far, they are not found in mammals. Regulatory circuits coupled to two-component systems exhibit a myriad of responses to environmental stimuli such as: redox potential, pH, specific metabolites, pressure, light and more recently to specific antimicrobial peptides that activate a sensor kinase responsible for expressing virulence factors through the active response regulator. In this review we explore general aspects on two-component systems that ultimately can play a role on virulence regulation, also the intriguing domain properties of the sensor kinases that can be a potential target for antimicrobial compounds. Only a handful of sensor kinases are extensively characterized, the vast majority belong to what we call 'the dark matter of bacterial signal transduction' since no known signal, structure and biochemical properties are available. Regulatory circuits from vertebrate pathogenic organisms can explain virulence in terms of either response to environmental factors or specific niche occupancy. Hopefully, knowledge on these signal transduction systems can lead to identify novel molecules that target two-component systems, since the increase of drug resistant microorganisms is worrisome.
Moduli Stabilization: Mathematical Aspects And Cosmological Applications
Prokushkin, S F
2005-01-01
We study the superpotential for the heterotic string compactified on non-Kähler complex manifolds. We show that many of the geometrical properties of these manifolds can be understood from the proposed superpotential. In particular we give an estimate of the radial modulus of these manifolds. We also show how the torsional constraints can be obtained from this superpotential. For a given complex n-fold M we present an explicit construction of all complex (n + 1)-folds which are principal holomorphic T2- fibrations over M. For physical applications we consider the case of M being a Calabi-Yau 2-fold. We show that for such M, there is a subclass of the 3-folds that we construct, which has natural families of non- Kähler SU(3)-structures satisfying the conditions for N = 1 supersymmetry in the heterotic string theory compactified on the 3-folds. We present examples in the aforementioned subclass with M being a K3-surface and a 4-torus. The distance between BPS branes in string theory corre...
Mathematical analysis of a nutrient-plankton system with delay.
Rehim, Mehbuba; Zhang, Zhenzhen; Muhammadhaji, Ahmadjan
2016-01-01
A mathematical model describing the interaction of nutrient-plankton is investigated in this paper. In order to account for the time needed by the phytoplankton to mature after which they can release toxins, a discrete time delay is incorporated into the system. Moreover, it is also taken into account discrete time delays which indicates the partially recycled nutrient decomposed by bacteria after the death of biomass. In the first part of our analysis the sufficient conditions ensuring local and global asymptotic stability of the model are obtained. Next, the existence of the Hopf bifurcation as time delay crosses a threshold value is established and, meanwhile, the phenomenon of stability switches is found under certain conditions. Numerical simulations are presented to illustrate the analytical results.
Commognitive analysis of undergraduate mathematics students' first encounter with the subgroup test
Ioannou, Marios
2017-08-01
This study analyses learning aspects of undergraduate mathematics students' first encounter with the subgroup test, using the commognitive theoretical framework. It focuses on students' difficulties as these are related to the object-level and metalevel mathematical learning in group theory, and, when possible, highlights any commognitive conflicts. In the data analysis, one can identify three types of difficulties, relevant to object-level learning: namely regarding the frequently observed confusion between groups and sets, the object-level rules of visual mediators, and the object-level rules of contextual notions, such as permutations, exponentials, sets and matrices. In addition, data analysis suggests two types of difficulties, relevant to metalevel learning. The first refers to the actual proof that the three conditions of subgroup test hold, and the second is related to syntactic inaccuracies, incomplete argumentation and problematic use of visual mediators. Finally, this study suggests that there are clear links between object-level and metalevel learning, mainly due to the fact that objectification of the various relevant mathematical notions influences the endorsement of the governing metarules.
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.
Mathematical analysis of a cholera model with public health interventions.
Mwasa, A; Tchuenche, J M
2011-09-01
Cholera, an acute gastro-intestinal infection and a waterborne disease continues to emerge in developing countries and remains an important global health challenge. We formulate a mathematical model that captures some essential dynamics of cholera transmission to study the impact of public health educational campaigns, vaccination and treatment as control strategies in curtailing the disease. The education-induced, vaccination-induced and treatment-induced reproductive numbers R(E), R(V), R(T) respectively and the combined reproductive number R(C) are compared with the basic reproduction number R(0) to assess the possible community benefits of these control measures. A Lyapunov functional approach is also used to analyse the stability of the equilibrium points. We perform sensitivity analysis on the key parameters that drive the disease dynamics in order to determine their relative importance to disease transmission and prevalence. Graphical representations are provided to qualitatively support the analytical results.
Directory of Open Access Journals (Sweden)
Lütfi İNCİKABI
2013-04-01
Full Text Available This study aimed to examine cross-national similarities and differences between problems involving Proportion and Ratio in Turkish mathematics textbooks and those in the U.S. mathematics textbooks. In particular, content analysis methodology was used to analyze these textbook problems at the 6th and 7th grade level in terms of their mathematics features, contextual features, and performance requirements. Compared with the U.S. textbooks, Turkish textbooks contained: 1 more pure mathematics problems but fewer real-life-application problems, 2 more Ratios and Proportions problems in the cognitive domains of applying and reasoning but fewer in the cognitive domain of knowing, and 3 more emphasis on explanations and solution processes in their problems but no problems involving the use of technology. In general, the U.S. textbooks included fewer multiple step problems and were dominated with problems of low mathematical and cognitive requirements.
Schiele, Miriam A; Reinhard, Julia; Reif, Andreas; Domschke, Katharina; Romanos, Marcel; Deckert, Jürgen; Pauli, Paul
2016-05-01
Most research on human fear conditioning and its generalization has focused on adults whereas only little is known about these processes in children. Direct comparisons between child and adult populations are needed to determine developmental risk markers of fear and anxiety. We compared 267 children and 285 adults in a differential fear conditioning paradigm and generalization test. Skin conductance responses (SCR) and ratings of valence and arousal were obtained to indicate fear learning. Both groups displayed robust and similar differential conditioning on subjective and physiological levels. However, children showed heightened fear generalization compared to adults as indexed by higher arousal ratings and SCR to the generalization stimuli. Results indicate overgeneralization of conditioned fear as a developmental correlate of fear learning. The developmental change from a shallow to a steeper generalization gradient is likely related to the maturation of brain structures that modulate efficient discrimination between danger and (ambiguous) safety cues.
Directory of Open Access Journals (Sweden)
Renata C. B. Madeo
2013-08-01
Full Text Available Lately, there has been an increasinginterest in hand gesture analysis systems. Recent works have employedpattern recognition techniques and have focused on the development of systems with more natural userinterfaces. These systems may use gestures to control interfaces or recognize sign language gestures, whichcan provide systems with multimodal interaction; or consist in multimodal tools to help psycholinguists tounderstand new aspects of discourse analysis and to automate laborious tasks.Gestures are characterizedby several aspects, mainly by movementsand sequence of postures. Since data referring to movementsorsequencescarry temporal information, this paper presents aliteraturereviewabouttemporal aspects ofhand gesture analysis, focusing on applications related to natural conversation and psycholinguisticanalysis, using Systematic Literature Review methodology. In our results, we organized works according totype of analysis, methods, highlighting the use of Machine Learning techniques, and applications.
The State of Mathematics in Our Schools.
Zelinka, Martha
1980-01-01
A commentary on the state of mathematics in schools that discusses positive aspects, such as the United States' successes in International Mathematics Olympiad, as well as the much-publicized criticisms of modern mathematics. (MK)
The mathematical analysis of a syntrophic relationship between two microbial species in a chemostat.
Sari, Tewfik; El Hajji, Miled; Harmand, Jerome
2012-07-01
A mathematical model involving a syntrophic relationship between two populations of bacteria in a continuous culture is proposed. A detailed qualitative analysis is carried out as well as the analysis of the local and global stability of the equilibria. We demonstrate, under general assumptions of monotonicity which are relevant from an applied point of view, the asymptotic stability of the positive equilibrium point which corresponds to the coexistence of the two bacteria. A syntrophic relationship in the anaerobic digestion process is proposed as a real candidate for this model.
Directory of Open Access Journals (Sweden)
Diana-Maria Drigă
2015-12-01
Full Text Available The concept of resilience has represented during the recent years a leading concern both in Romania, within the European Union and worldwide. Specialists in economics, management, finance, legal sciences, political sciences, sociology, psychology, grant a particular interest to this concept. Multidisciplinary research of resilience has materialized throughout the time in multiple conceptualizations and theorizing, but without being a consensus between specialists in terms of content, specificity and scope. Through this paper it is intended to clarify the concept of resilience, achieving an exploration of the evolution of this concept in ecological, social and economic environment. At the same time, the paper presents aspects of feedback mechanisms and proposes a formalization of resilience using the logic and mathematical analysis.
Lamb, John H.
2010-01-01
Increased reading difficulty of mathematics assessment items has been shown to negatively affect student performance. The advent of high-stakes testing, which has serious ramifications for students' futures and teachers' careers, necessitates analysis of reading difficulty on state assessment items and student performance on those items. Using…
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.
Contact analysis and mathematical modeling of traveling wave ultrasonic motors.
Zhu, Meiling
2004-06-01
An analysis of the contact layer and a mathematical modeling of traveling wave ultrasonic motors (TWUM) are presented for the guidance of the design of contact layer and the analyses of the influence of the compressive force and contact layer on motor performance. The proposed model starts from a model previously studied but differs from that model in that it adds the analysis of the contact layer and derives the steady-state solutions of the nonlinear equations in the frequency domain, rather than in the time domain, for the analyses of vibrational responses of the stator and operational characteristics of the motor. The maximum permissible compressive force of the motor, the influences of the contact layer material, the thickness of the contact layer, and the compressive force on motor performance have been discussed. The results show that by using the model, one can understand the influence of the compressive force and contact layer material on motor performance, guide the choice of proper contact layer material, and calculate the maximum permissible compressive force and starting voltage.
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.
Bucur, Amelia
2015-09-01
The aim of this paper is to present aspects of mathematical modeling for the hierarchization of study programs from universities, based on several quality characteristics. The tools used pertain to multicriterial optimization, to the different methods of assessing importance coefficients, to the utility theory, the fuzzy formalism, and to the fuzzy simple additive weighting method. The conclusion is that multicriterial decision-making methods can be efficiently used in assessing the quality of study programs, noting that, just like other methods from the decision theory, the multicriterial decision-making methods highlight aspects of problems differently, therefore, there can be no comparison or competitiveness between them, and choosing one over the other is up to the decision-maker.
Canuto, Claudio
2015-01-01
The purpose of the volume is to provide a support for a first course in Mathematics. The contents are organised to appeal especially to Engineering, Physics and Computer Science students, all areas in which mathematical tools play a crucial role. Basic notions and methods of differential and integral calculus for functions of one real variable are presented in a manner that elicits critical reading and prompts a hands-on approach to concrete applications. The layout has a specifically-designed modular nature, allowing the instructor to make flexible didactical choices when planning an introductory lecture course. The book may in fact be employed at three levels of depth. At the elementary level the student is supposed to grasp the very essential ideas and familiarise with the corresponding key techniques. Proofs to the main results befit the intermediate level, together with several remarks and complementary notes enhancing the treatise. The last, and farthest-reaching, level requires the additional study of ...
An Analysis of the Generalized Lambda Distribution
1993-03-01
Mendenhall, Wackerly and Scheaffer [8]. The first moment about the origin describes the center of a pdf and is commonly referred to as the mean (I). The... Scheaffer . Mathematical Statistics with Applications. PWS-Kent Publishing, 1990. 9. Edward F. Mykytka. Some Useful Properties and Methods for
Analysis of anatomic variability in children with low mathematical skills
Han, Zhaoying; Fuchs, Lynn; Davis, Nikki; Cannistraci, Christopher J.; Anderson, Adam W.; Gore, John C.; Dawant, Benoit M.
2008-03-01
Mathematical difficulty affects approximately 5-9% of the population. Studies on individuals with dyscalculia, a neurologically based math disorder, provide important insight into the neural correlates of mathematical ability. For example, cognitive theories, neuropsychological studies, and functional neuroimaging studies in individuals with dyscalculia suggest that the bilateral parietal lobes and intraparietal sulcus are central to mathematical performance. The purpose of the present study was to investigate morphological differences in a group of third grade children with poor math skills. We compare population averages of children with low math skill (MD) to gender and age matched controls with average math ability. Anatomical data were gathered with high resolution MRI and four different population averaging methods were used to study the effect of the normalization technique on the results. Statistical results based on the deformation fields between the two groups show anatomical differences in the bilateral parietal lobes, right frontal lobe, and left occipital/parietal lobe.
Functional data analysis of generalized regression quantiles
Guo, Mengmeng
2013-11-05
Generalized regression quantiles, including the conditional quantiles and expectiles as special cases, are useful alternatives to the conditional means for characterizing a conditional distribution, especially when the interest lies in the tails. We develop a functional data analysis approach to jointly estimate a family of generalized regression quantiles. Our approach assumes that the generalized regression quantiles share some common features that can be summarized by a small number of principal component functions. The principal component functions are modeled as splines and are estimated by minimizing a penalized asymmetric loss measure. An iterative least asymmetrically weighted squares algorithm is developed for computation. While separate estimation of individual generalized regression quantiles usually suffers from large variability due to lack of sufficient data, by borrowing strength across data sets, our joint estimation approach significantly improves the estimation efficiency, which is demonstrated in a simulation study. The proposed method is applied to data from 159 weather stations in China to obtain the generalized quantile curves of the volatility of the temperature at these stations. © 2013 Springer Science+Business Media New York.
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.
Rancic, Milica
2016-01-01
This book highlights the latest advances in engineering mathematics with a main focus on the mathematical models, structures, concepts, problems and computational methods and algorithms most relevant for applications in modern technologies and engineering. It addresses mathematical methods of algebra, applied matrix analysis, operator analysis, probability theory and stochastic processes, geometry and computational methods in network analysis, data classification, ranking and optimisation. The individual chapters cover both theory and applications, and include a wealth of figures, schemes, algorithms, tables and results of data analysis and simulation. Presenting new methods and results, reviews of cutting-edge research, and open problems for future research, they equip readers to develop new mathematical methods and concepts of their own, and to further compare and analyse the methods and results discussed. The book consists of contributed chapters covering research developed as a result of a focused interna...
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.
da Silva, Roberto; Peretti, Debora E
2016-01-01
In this paper, we explore the stability of an inverted pendulum under a generalized parametric excitation described by a superposition of $N$ cosines with different amplitudes and frequencies, based on a simple stability condition that does not require any use of Lyapunov exponent, for example. Our analysis is separated in 3 different cases: $N=1$, $N=2$, and $N$ very large. Our results were obtained via numerical simulations by fourth-order Runge Kutta integration of the non-linear equations. We also calculate the effective potential also for $N>2$. We show then that numerical integrations recover a wider region of stability that are not captured by the (approximated) analytical method. We also analyze stochastic stabilization here: firstly, we look the effects of external noise in the stability diagram by enlarging the variance, and secondly, when $N$ is large, we rescale the amplitude by showing that the diagrams for time survival of the inverted pendulum resembles the exact case for $N=1$. Finally, we fin...
Mathematical analysis and numerical simulation of a model of morphogenesis.
Muñoz, Ana I; Tello, José Ignacio
2011-10-01
We consider a simple mathematical model of distribution of morphogens (signaling molecules responsible for the differentiation of cells and the creation of tissue patterns). The mathematical model is a particular case of the model proposed by Lander, Nie and Wan in 2006 and similar to the model presented in Lander, Nie, Vargas and Wan 2005. The model consists of a system of three equations: a PDE of parabolic type with dynamical boundary conditions modelling the distribution of free morphogens and two ODEs describing the evolution of bound and free receptors. Three biological processes are taken into account: diffusion, degradation and reversible binding. We study the stationary solutions and the evolution problem. Numerical simulations show the behavior of the solution depending on the values of the parameters.
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...
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).
Mathematical analysis of dermal absorption rate of heavy metals.
Batkin, Izmail; Bolic, Miodrag
2015-08-01
Presently 90 - 95% of children in the US wear disposable diapers before completing their toilet training at average age of 30 months. The diaper absorbs urine and liquid component from feces contaminated with excreted toxicants. In this initial study, we posit that the long contact between the diaper and the skin leads to increased dermal reabsorption of excreted body toxicants, mainly heavy metals, which are statistically associated with autism and neurodevelopmental disorder. We developed a mathematical model to analyse the increase of the level of toxicants due to dermal reabsorption after excretion. This simple kinetic model gives us the average reabsorbtion factor in the range of 1.6 to 5. The limitation of this work is that only mathematical model has been considered and it has not been verified experimentally.
Carroll, Jean
1994-12-01
The negative attitudes of some student teachers towards mathematics and the inadequacy of their mathematical backgrounds have been a concern of mathematics educators for many years. In an attempt to understand the interaction of cognitive and affective factors in mathematics learning, this paper presents a case study of one preservice early childhood/primary teacher education student's experiences of learning mathematics. The study identifies issues which are of concern both to teachers and to teacher educators.
VedoVatto, T.; Nascimento, A. D. C.; Filho, W. R. Miranda; Lima, M. C. S.; Pinho, L. G. B.; Cordeiro, G. M.
2016-01-01
Real data from applications in the survival context have required the use of more flexible models. A new four-parameter model called the Exponentiated Generalized Nadarajah-Haghighi (EGNH) distribution has been introduced in order to verify this requirement.
Mathematical foundations of biomechanics.
Niederer, Peter F
2010-01-01
The aim of biomechanics is the analysis of the structure and function of humans, animals, and plants by means of the methods of mechanics. Its foundations are in particular embedded in mathematics, physics, and informatics. Due to the inherent multidisciplinary character deriving from its aim, biomechanics has numerous connections and overlapping areas with biology, biochemistry, physiology, and pathophysiology, along with clinical medicine, so its range is enormously wide. This treatise is mainly meant to serve as an introduction and overview for readers and students who intend to acquire a basic understanding of the mathematical principles and mechanics that constitute the foundation of biomechanics; accordingly, its contents are limited to basic theoretical principles of general validity and long-range significance. Selected examples are included that are representative for the problems treated in biomechanics. Although ultimate mathematical generality is not in the foreground, an attempt is made to derive the theory from basic principles. A concise and systematic formulation is thereby intended with the aim that the reader is provided with a working knowledge. It is assumed that he or she is familiar with the principles of calculus, vector analysis, and linear algebra.
DEFF Research Database (Denmark)
Videbæk Le, Jette; Pedersen, Line Bjørnskov; Riisgaard, Helle
2017-01-01
Background There is a substantial variation in how different general practices manage knowledge implementation, including the degree to which activities are collectively and formally organised. Yet, it is unclear how these differences in implementation activities affect quality of care. Aim To in...
Davis, C. E.; Osler, James E.
2013-01-01
This paper details the outcomes of a qualitative in-depth investigation into teacher education mathematics preparation. This research is grounded in the notion that mathematics teacher education students (as "degree seeking candidates") need to develop strong foundations of mathematical practice as defined by the Common Core State…
Mathematical Modelling and Experimental Analysis of Early Age Concrete
DEFF Research Database (Denmark)
Hauggaard-Nielsen, Anders Boe
1997-01-01
The report deals with mathematical models for concrete at early age. In the hardening process chemical reactions take place and the concrete skeleton is created. The processes changes the moisture content and produces heat. The associated temperature rise gives expansion of the material which may...
Analysis of rear end impact using mathematical human modelling
Happee, R.; Meijer, R.; Horst, M.J. van der; Ono, K.; Yamazaki, K.
2000-01-01
At TNO an omni-directional mathematical human body model has been developed. Until now this human model has been validated for frontal and lateral loading using response data of volunteer and post mortem human subject (PMHS) sled tests. For rearward loading it has been validated for high speed impac
Classroom Data Analysis with the Five Strands of Mathematical Proficiency
Groth, Randall E.
2017-01-01
Qualitative classroom data from video recordings and students' written work can play important roles in improving mathematics instruction. In order to take full advantage of these data sources, it is helpful to have a strong analytic lens to orient one's reflections on the data. One promising analytic lens is the National Research Council's five…
An overview of the mathematical and statistical analysis component of RICIS
Hallum, Cecil R.
1987-01-01
Mathematical and statistical analysis components of RICIS (Research Institute for Computing and Information Systems) can be used in the following problem areas: (1) quantification and measurement of software reliability; (2) assessment of changes in software reliability over time (reliability growth); (3) analysis of software-failure data; and (4) decision logic for whether to continue or stop testing software. Other areas of interest to NASA/JSC where mathematical and statistical analysis can be successfully employed include: math modeling of physical systems, simulation, statistical data reduction, evaluation methods, optimization, algorithm development, and mathematical methods in signal processing.
Analysis of Software Design Artifacts for Socio-Technical Aspects
Damaševičius, Robertas; Kaunas University of Technology
2007-01-01
Software systems are not purely technical objects. They are designed, constructed and used by people. Therefore, software design process is not purely a technical task, but a socio-technical process embedded within organizational and social structures. These social structures influence and govern their work behavior and final work products such as program source code and documentation. This paper discusses the organizational, social and psychological aspects of software design; and formulates...
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.
Causal and Topological Aspects in Special and General Theory of Relativity
Saraykar, R V
2014-01-01
In this article we present a review of a geometric and algebraic approach to causal cones and describe cone preserving transformations and their relationship with the causal structure related to special and general relativity. We describe Lie groups, especially matrix Lie groups, homogeneous and symmetric spaces and causal cones and certain implications of these concepts in special and general relativity, related to causal structure and topology of space-time. We compare and contrast the results on causal relations with those in the literature for general space-times and compare these relations with K-causal maps. We also describe causal orientations and their implications for space-time topology and discuss some more topologies on space-time which arise as an application of domain theory. For the sake of completeness, we reproduce proofs of certain theorems which we proved in our earlier work.
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.
Gardiner-Shires, Alison Marie; Heinerichs, Scott
2012-01-01
Context: A general education course taught by athletic training education faculty has the potential to expose the entire student body to the athletic training profession in a unique way while also meeting requirements of the Commission on Accreditation of Athletic Training Education. Objective: To introduce a detailed case study of a general…
Damert, H G; Altmann, S; Stübs, P; Infanger, M; Meyer, F
2015-02-01
There is overlap between general, abdominal and vascular surgery on one hand and plastic surgery on the other hand, e.g., in hernia surgery, in particular, recurrent hernia, reconstruction of the abdominal wall or defect closure after abdominal or vascular surgery. Bariatric operations involve both special fields too. Plastic surgeons sometimes use skin and muscle compartments of the abdominal wall for reconstruction at other regions of the body. This article aims to i) give an overview about functional, anatomic and clinical aspects as well as the potential of surgical interventions in plastic surgery. General/abdominal/vascular surgeons can benefit from this in their surgical planning and competent execution of their own surgical interventions with limited morbidity/lethality and an optimal, in particular, functional as well as aesthetic outcome, ii) support the interdisciplinary work of general/abdominal/vascular and plastic surgery, and iii) provide a better understanding of plastic surgery and its profile of surgical interventions and options.
MECHANISM ANALYSIS AND MATHEMATICAL DESCRIPTION OF MECHANICAL ABRUP TFAULTS
Institute of Scientific and Technical Information of China (English)
无
1999-01-01
Gradual faults and abrupt faults of mechanical systems are differentiated by variation patterns of state var ibles.After the reasons of abrupt faults are analyzed by nonlinear dynamics,two methods establishing the mathematical models for abrupt faults are presented.As an example,a cusp catastrophe model of the vibration amplitudes of a Jeffcott rotor with nonlinear stiffness and its parameter condition of the vibration state catastrophe are obtained.
Directory of Open Access Journals (Sweden)
Vaibhavi Joshipura
2013-01-01
Conclusion: The disorder may not be segregating as an autosomal recessive trait and we could have been misled by consanguinity in the family. It could be a multifactorial trait, or it could be still segregating as an autosomal recessive trait, but the region of homozygosity could be small and we failed to detect it using microsatellite markers. Therefore, SNP-marker-based analysis is warranted in future.
Mathematical Theory of Compressible Viscous Fluids: Analysis and Numerics
Feireisl, E. (Eduard); Karper, T.; Pokorný, M.
2016-01-01
This book offers an essential introduction to the mathematical theory of compressible viscous fluids. The main goal is to present analytical methods from the perspective of their numerical applications. Accordingly, we introduce the principal theoretical tools needed to handle well-posedness of the underlying Navier-Stokes system, study the problems of sequential stability, and, lastly, construct solutions by means of an implicit numerical scheme. Offering a unique contribution – by exploring...
Analysis Of Aspects Of Messages Hiding In Text Environments
Directory of Open Access Journals (Sweden)
Afanasyeva Olesya
2015-09-01
Full Text Available In the work are researched problems, which arise during hiding of messages in text environments, being transmitted by electronic communication channels and the Internet. The analysis of selection of places in text environment (TE, which can be replaced by word from the message is performed. Selection and replacement of words in the text environment is implemented basing on semantic analysis of text fragment, consisting of the inserted word, and its environment in TE. For implementation of such analysis is used concept of semantic parameters of words coordination and semantic value of separate word. Are used well-known methods of determination of values of these parameters. This allows moving from quality level to quantitative level analysis of text fragments semantics during their modification by word substitution. Invisibility of embedded messages is ensured by providing preset values of the semantic cooperation parameter deviations.
The purpose of the general practice consultation from the patients perspective - theoretical aspects
DEFF Research Database (Denmark)
Thorsen, Hanne; Witt, Klaus; Malterud, Kirsti
2001-01-01
Consultation purposes, general practice, patients´expectations, patients satosfaction, patientcenteredness......Consultation purposes, general practice, patients´expectations, patients satosfaction, patientcenteredness...
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.
Experimental and Mathematical Analysis of Multilayer Insulation below 80 K
Chorowski, M; Parente, C; Riddone, G
2000-01-01
The Large Hadron Collider [1], presently under construction at CERN, will make an extensive use of multilayer insulation system (MLI). The total surface to be insulated will be of about 80000 m2. A mathematical model has been developed to describe the heat flux through MLI from 80 K to 4.2 K. The total heat flux between the layers is the result of three distinct heat transfer modes: radiation, residual gas conduction and solid conduction. The mathematical model enables prediction of MLI behavior with regard to different MLI parameters, such as gas insulation pressure, number of layers and boundary temperatures. The calculated values have been compared to the experimental measurements carried out at CERN. Theoretical and experimental results revealed to be in good agreement, especially for insulation vacuum between 10-5 Pa and 10-3 Pa.
A Mathematical and Sociological Analysis of Google Search Algorithm
2013-01-16
it is the most used computational algorithm in the world. More and more websites such as Facebook, Amazon, Netflix , and etc.. use similar search...matrix completion is a research topic in mathematics which is recently actively studied. It starts from the well-known Netflix problem. Indeed... Netflix (cf. [36]) made available publicly such a set of data with about 105 known entries of its movie rating matrix of size about 5 × 105 times 2 × 105
Jamil, Norazaliza Mohd; Wang, Qi
2017-09-01
Renewable energy or biofuel from lignocellulosic biomass is an alternative way to replace the depleting fossil fuels. The production cost can be reduced by increasing the concentration of biomass particles. However, lignocellulosic biomass is a suspension of natural fibres, and processing at high solid concentration is a challenging task. Thus, understanding the factors that affect the rheology of biomass suspension is crucial in order to maximize the production at a minimum cost. Our aim was to develop a mathematical model for enzymatic hydrolysis of cellulose by combining three scales: the macroscopic flow field, the mesoscopic particle orientation, and the microscopic reactive kinetics. The governing equations for the flow field, particle stress, kinetic equations, and particle orientation were coupled and were simultaneously solved using a finite element method based software, COMSOL. One of the main results was the changes in rheology of biomass suspension were not only due to the decrease in volume fraction of particles, but also due the types of fibres. The results from the simulation model agreed qualitatively with the experimental findings. This approach has enables us to obtain better predictive capabilities, hence increasing our understanding on the behaviour of biomass suspension.
Investigating Student Use of Electronic Support Tools and Mathematical Reasoning
Higgins, Kristina N.; Crawford, Lindy; Huscroft-D'Angelo, Jacqueline; Horney, Mark
2016-01-01
Mathematical reasoning involves comprehending mathematical information and concepts in a logical way and forming conclusions and generalizations based on this comprehension. Computer-based learning has been incorporated into classrooms across the country, and specific aspects of technology need to be studied to determine how programs are…
Mathematical Analysis of Piaget's Grouping Concept. Papy's Minicomputer as a Grouping
Steiner, H. G.
1974-01-01
Through a mathematical analysis, Piaget's grouping concept can be formally interpreted as being a hybrid between the mathematical concepts of a group and a lattice. Some relevant pedagogical models are presented. Activities with Cuisenaire Rods, Dienes Blocks, and Papy's Minicomputer are shown to take place in groupings. (LS)
Directory of Open Access Journals (Sweden)
Rebecca Nthogo Lekoko
2006-04-01
Full Text Available The findings of a phenomenological interview study with women street vendors showed a strong link between participants’ perceptions of everyday use of mathematical literacy and the speculations that mathematical use arose spontaneously in response to a practical need. The concept of intuitive mathematics as used indicates that mathematical thinking is an indispensable element of everyday conversation. Although the study finds that intuition and spontaneity are essential principles of lifelong learning, it concludes with recommendations for an empowerment curriculum that interweaves participants’ experiences and intuition with formal/academic mathematical literacy and psychosocial skills necessary for success in a highly competitive business world.
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
Mathematique et Informatique, Aspect Didactique (Mathematics and Informatics, the Didactic Aspect).
Pochon, Luc-Olivier
Both mathematics and informatics share common characteristics. Several didacticians propose therefore to define didactic situations permitting learners to "co-construct" knowledge of mathematics and informatics. In this document, the idea is resumed and a certain number of "functional structures" are proposed. These sets of problems take on a…
Fongaro, Lorenzo; Alamprese, Cristina; Casiraghi, Ernestina
2015-03-01
During ripening of salami, colour changes occur due to oxidation phenomena involving myoglobin. Moreover, shrinkage due to dehydration results in aspect modifications, mainly ascribable to fat aggregation. The aim of this work was the application of image analysis (IA) and multivariate image analysis (MIA) techniques to the study of colour and aspect changes occurring in salami during ripening. IA results showed that red, green, blue, and intensity parameters decreased due to the development of a global darker colour, while Heterogeneity increased due to fat aggregation. By applying MIA, different salami slice areas corresponding to fat and three different degrees of oxidised meat were identified and quantified. It was thus possible to study the trend of these different areas as a function of ripening, making objective an evaluation usually performed by subjective visual inspection. Copyright © 2014 Elsevier Ltd. All rights reserved.
Some aspects of the local theory of generalized Dhombres functional equations in the complex domain
Directory of Open Access Journals (Sweden)
Tomaschek Jörg
2012-08-01
Full Text Available We study the generalized Dhombres functional equation f(zf(z = ϕ(f(z in the complex domain. The function ϕ is given and we are looking for solutions f with f(0 = w0 and w0 is a primitive root of unity of order l ≥ 2. All formal solutions for this case are described in this work, for the situation where ϕ can be transformed into a function which is linearizable and local analytic in a neighbourhood of zero we also show that we obtain local analytic solutions. We also discuss an example where it is possible to use other methods than we use in the general case. Nous étudions la fonctionnelle de Dhombres f(zf(z = ϕ(f(z dans le plan complexe. La fonction ϕ est donnée et nous cherchons les solutions f avec f(0 = w0 où w0 est une racine primitive de l’unité d’ordre l ≥ 2. Nous décrivons dans ce travail toutes les solutions formelles dans ce cas, et lorsque ϕ peut être transformée en une fonction linéarisable et localement analytique au voisinage de zéro nous montrons également comment obtenir des solutions analytiques locales. Nous discutons enfin un exemple où il est possible d’utiliser des méthodes différentes de celles que nous mettons en œuvre dans le cas général.
A mathematical analysis of multiple-target SELEX.
Seo, Yeon-Jung; Chen, Shiliang; Nilsen-Hamilton, Marit; Levine, Howard A
2010-10-01
SELEX (Systematic Evolution of Ligands by Exponential Enrichment) is a procedure by which a mixture of nucleic acids can be fractionated with the goal of identifying those with specific biochemical activities. One combines the mixture with a specific target molecule and then separates the target-NA complex from the resulting reactions. The target-NA complex is separated from the unbound NA by mechanical means (such as by filtration), the NA is eluted from the complex, amplified by PCR (polymerase chain reaction), and the process repeated. After several rounds, one should be left with the nucleic acids that best bind to the target. The problem was first formulated mathematically in Irvine et al. (J. Mol. Biol. 222:739-761, 1991). In Levine and Nilsen-Hamilton (Comput. Biol. Chem. 31:11-25, 2007), a mathematical analysis of the process was given. In Vant-Hull et al. (J. Mol. Biol. 278:579-597, 1998), multiple target SELEX was considered. It was assumed that each target has a single nucleic acid binding site that permits occupation by no more than one nucleic acid. Here, we revisit Vant-Hull et al. (J. Mol. Biol. 278:579-597, 1998) using the same assumptions. The iteration scheme is shown to be convergent and a simplified algorithm is given. Our interest here is in the behavior of the multiple target SELEX process as a discrete "time" dynamical system. Our goal is to characterize the limiting states and their dependence on the initial distribution of nucleic acid and target fraction components. (In multiple target SELEX, we vary the target component fractions, but not their concentrations, as fixed and the initial pool of nucleic acids as a variable starting condition). Given N nucleic acids and a target consisting of M subtarget component species, there is an M × N matrix of affinities, the (i,j) entry corresponding to the affinity of the jth nucleic acid for the ith subtarget. We give a structure condition on this matrix that is equivalent to the following
Shrestha, Durga; Joyce, Catherine M
2011-01-01
The Australian general practitioner (GP) workforce, especially younger generation GPs and female GPs, increasingly prioritises work-life balance (WLB). Good WLB is associated with decreased interest of medical students in general practice as a speciality choice as well as good health and wellbeing, and decisions of GPs to retire early. Therefore, understanding the role played by different factors in achieving WLB is crucial to ensure a sufficient GP workforce necessary to meet the rising demands of health care. There is a dearth of empirical, quantitative, large, population-based studies assessing the level of WLB in the Australian GP population as well as contributing and consequent factors. Our study fills this identified gap in the current literature. This study aimed to investigate the extent, determinants and possible consequences of WLB of Australian GPs. Data for this study come from the baseline cohort of the Medicine in Australia: Balancing Employment and Life (MABEL) longitudinal, population-level survey. Questionnaires tailored specifically for GPs and GP registrars were sent to all clinically active GPs registered in the Australian Medical Publishing Co. (AMPCo) database (n=22137), with a choice of completing either a paper or online version. Data were collected between June and December 2008. STATA (10.0) was used for conducting weighted data analyses. Regression methods were applied for assessing the associations between dependent and independent variables. Of the 3906 GPs (17.6%) who responded, 53% reported that the balance between their personal and professional commitments was about right. Generation X GPs and females reported a better WLB than baby boomers and males respectively. However, those reporting good WLB also worked significantly fewer hours than those reporting poor WLB. GPs who reported good opportunities for leisure activities and perceived that they have good health also reported better WLB. Contrastingly, those reporting difficulty
Betz, Oliver; Wegst, Ulrike; Weide, Daniela; Heethoff, Michael; Helfen, Lukas; Lee, Wah-Keat; Cloetens, Peter
2007-07-01
Synchrotron-generated X-rays provide scientists with a multitude of investigative techniques well suited for the analysis of the composition and structure of all types of materials and specimens. Here, we describe the properties of synchrotron-generated X-rays and the advantages that they provide for qualitative morphological research of millimetre-sized biological organisms and biomaterials. Case studies of the anatomy of insect heads, of whole microarthropods and of the three-dimensional reconstruction of the cuticular tendons of jumping beetles, all performed at the beamline ID19 of the European Synchrotron Radiation Facility (ESRF), are presented to illustrate the techniques of phase-contrast tomography available for anatomical and structural investigations. Various sample preparation techniques are described and compared and experimental settings that we have found to be particularly successful are given. On comparing the strengths and weaknesses of the technique with traditional histological thin sectioning, we conclude that synchrotron radiation microtomography has a great potential in biological microanatomy.
Contextual Aspects of Smart City Energy Systems Analysis
DEFF Research Database (Denmark)
Thellufsen, Jakob Zinck
The thesis defines the concept of smart city energy systems. The thesis emphasises the need to investigate the smart city energy system and two contextual aspects. The system integration context and the geographical context. The system integration context emphasises that increased interrelation...... between the different energy sectors increases the efficiency of the system. However, it also impacts the implementation of single technologies in the smart city energy system. The thesis discusses methods and tools to assess the system integration context. Smart cities, and other concepts for urban...... development, often strives towards some sort of sustainability target. However, to consider a city and the smart city energy system sustainable, they cannot limit other energy systems from becoming sustainable. It is therefore necessary to investigate the geographical context. This thesis develops tools...
Episodes in the mathematics of medieval Islam
Berggren, J L
1986-01-01
From the reviews: The book is, in spite of the author's more modest claims, an introductory survey of main developments in those disciplines which were particularly important in Medieval Islamic mathematics...No knowledge of mathematics (or of the history of mathematics) beyond normal high-school level is presupposed, and everything required beyond that (be it Apollonian theory of conics or the definitions of celestial circles) is explained carefully and clearly. Scattered throughout the work are a number of lucid remarks on the character of Islamic mathematics or of mathematical work in general. The book will hence not only be an excellent textbook for the teaching of the history of mathematics but also for the liberal art aspect of mathematics teaching in general. - Jens Høyrup, Mathematical Reviews ...as a textbook, this work is highly commendable...It is definitely the product of a skillful mathematician who has collected over the years a reasonably large number of interesting problems from medieval Arab...
Photonic Crystals Mathematical Analysis and Numerical Approximation
Dörfler, Willy; Plum, Michael; Schneider, Guido; Wieners, Christian
2011-01-01
This book concentrates on the mathematics of photonic crystals, which form an important class of physical structures investigated in nanotechnology. Photonic crystals are materials which are composed of two or more different dielectrics or metals, and which exhibit a spatially periodic structure, typically at the length scale of hundred nanometers. In the mathematical analysis and the numerical simulation of the partial differential equations describing nanostructures, several mathematical difficulties arise, e. g., the appropriate treatment of nonlinearities, simultaneous occurrence of contin
A critical review of mathematical models and data used in diabetology
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Chetouani A
2006-06-01
Full Text Available Abstract The literature dealing with mathematical modelling for diabetes is abundant. During the last decades, a variety of models have been devoted to different aspects of diabetes, including glucose and insulin dynamics, management and complications prevention, cost and cost-effectiveness of strategies and epidemiology of diabetes in general. Several reviews are published regularly on mathematical models used for specific aspects of diabetes. In the present paper we propose a global overview of mathematical models dealing with many aspects of diabetes and using various tools. The review includes, side by side, models which are simple and/or comprehensive; deterministic and/or stochastic; continuous and/or discrete; using ordinary differential equations, partial differential equations, optimal control theory, integral equations, matrix analysis and computer algorithms.
Analysis of a Mathematical Model of Ischemic Cutaneous wounds
Friedman, Avner; Xue, Chuan
2009-01-01
Chronic wounds represent a major public health problem affecting 6.5 million people in the United States. Ischemia represents a serious complicating factor in wound healing. In this paper we analyze a recently developed mathematical model of ischemic dermal wounds. The model consists of a coupled system of partial differential equations in the partially healed region, with the wound boundary as a free boundary. The extracellular matrix (ECM) is assumed to be viscoelastic, and the free boundary moves with the velocity of the ECM at the boundary of the open wound. The model equations involve the concentrations of oxygen, cytokines, and the densities of several types of cells. The ischemic level is represented by a parameter which appears in the boundary conditions, 0 <= gamma < 1; gamma near 1 corresponds to extreme ischemia and gamma = 0 corresponds to normal non-ischemic conditions. We establish global existence and uniqueness of the free boundary problem and study the dependence of the free boundary on...
Analysis of a mathematical model describing necrotic tumor growth
Escher, Joachim; Matioc, Bogdan-Vasile
2010-01-01
In this paper we study a model describing the growth of necrotic tumors in different regimes of vascularisation. The tumor consists of a necrotic core of death cells and a surrounding nonnecrotic shell. The corresponding mathematical formulation is a moving boundary problem where both boundaries delimiting the nonnecrotic shell are allowed to evolve in time.We determine all radially symmetric stationary solutions of the problem and reduce the moving boundary problem into a nonlinear evolution. Parabolic theory provides us the perfect context in order to show local well-posed of the problem for small initial data.
Analysis of central venous pressure (CVP) signals using mathematical methods.
Atefvahid, Parham; Hassani, Kamran; Jafarian, Kamal; Doyle, D John; Ahmadi, Hessam
2017-06-01
Central venous pressure (CVP) is an important clinical parameter for physicians but only the absolute CVP value is typically monitored in the intensive care unit (ICU). In this study, we propose a novel mathematical method to present and analyze CVP signals. A total of 44 suitable samples were chosen from a total of 65 collected in an ICU. Pre-processing of the samples included rate reduction and digital filtering. The statistical features of time and frequency domain, wavelet, and empirical mode decomposition of these signals were extracted. We found no significant difference among the CVP signals regarding sex, smoking, coronary disease, and respiration mode of the samples.
Dataset for an analysis of communicative aspects of finance.
Natalya Zavyalova
2017-04-01
The article describes a step-by-step strategy for designing a universal comprehensive vision of a vast majority of financial research topics. The strategy is focused around the analysis of the retrieval results of the word processing system Serelex which is based on the semantic similarity measure. While designing a research topic, scientists usually employ their individual background. They rely in most cases on their individual assumptions and hypotheses. The strategy, introduced in the article, highlights the method of identifying components of semantic maps which can lead to a better coverage of any scientific topic under analysis. On the example of the research field of finance we show the practical and theoretical value of semantic similarity measurements, i.e., a better coverage of the problems which might be included in the scientific analysis of financial field. At the designing stage of any research scientists are not immune to an insufficient and, thus, erroneous spectrum of problems under analysis. According to the famous maxima of St. Augustine, 'Fallor ergo sum', the researchers' activities are driven along the way from one mistake to another. However, this might not be the case for the 21st century science approach. Our strategy offers an innovative methodology, according to which the number of mistakes at the initial stage of any research may be significantly reduced. The data, obtained, was used in two articles (N. Zavyalova, 2017) [7], (N. Zavyalova, 2015) [8]. The second stage of our experiment was driven towards analyzing the correlation between the language and income level of the respondents. The article contains the information about data processing.
Mathematics of aperiodic order
Lenz, Daniel; Savinien, Jean
2015-01-01
What is order that is not based on simple repetition, that is, periodicity? How must atoms be arranged in a material so that it diffracts like a quasicrystal? How can we describe aperiodically ordered systems mathematically? Originally triggered by the – later Nobel prize-winning – discovery of quasicrystals, the investigation of aperiodic order has since become a well-established and rapidly evolving field of mathematical research with close ties to a surprising variety of branches of mathematics and physics. This book offers an overview of the state of the art in the field of aperiodic order, presented in carefully selected authoritative surveys. It is intended for non-experts with a general background in mathematics, theoretical physics or computer science, and offers a highly accessible source of first-hand information for all those interested in this rich and exciting field. Topics covered include the mathematical theory of diffraction, the dynamical systems of tilings or Delone sets, their cohomolog...
Scott, Lori N; Kim, Yookyung; Nolf, Kimberly A; Hallquist, Michael N; Wright, Aidan G C; Stepp, Stephanie D; Morse, Jennifer Q; Pilkonis, Paul A
2013-08-01
Emotional dysregulation and impaired attachment are seen by many clinical researchers as central aspects of borderline personality disorder (BPD). Alternatively, these constructs may represent general impairments in personality that are nonspecific to BPD. Using multitraitmultimethod models, the authors examined the strength of associations among preoccupied attachment, difficulties with emotion regulation, BPD features, and features of two other personality disorders (i.e., antisocial and avoidant) in a combined psychiatric outpatient and community sample of adults. Results suggested that preoccupied attachment and difficulties with emotion regulation shared strong positive associations with each other and with each of the selected personality disorders. However, preoccupied attachment and emotional dysregulation were more strongly related to BPD features than to features of other personality disorders. Findings suggest that although impairments in relational and emotional domains may underlie personality pathology in general, preoccupied attachment and emotional dysregulation also have specificity for understanding core difficulties in those with BPD.
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…
Technical aspects of nuclear microprobe analysis of senile plaques from alzheimer patients
Larsson, N. P.-O.; Tapper, U. A. S.; Sturesson, K.; Odselius, R.; Brun, A.
1990-04-01
Alzheimer's disease, a common form of senile dementia, has been proposed to be caused by aluminium. One of the interesting structures to be studied, senile plaque cores in the brain, have centres of only about 10 μm. We have investigated the possibility of applying nuclear microprobes to sections containing senile plaques. An alternative staining procedure, TMToluidin blue staining using a spray technique, is also presented. An outline is given of a procedure for preparing senile plaque specimens for nuclear microprobe analysis. This includes a technique for accurate ion beam positioning, utilizing electron microscopy-grids. The subject may be of general interest since sample preparation is one of the most important aspects in microprobe analysis of biological matter.
Quality Aspects in Particulate Analysis
Merkus, Henk G.
The quality of particle size analysis for the purpose of control of product quality consists of several parts. First, the most relevant parameter(s) have to be chosen to represent the quality of a specific product in a specific application. Some background is given, but an optimum answer to any new product with new properties can only be found by thorough investigation, knowledge and experience. Secondly, the quality aspects of both technique and total procedure for measurement have to be considered in relation to the requirements set for product performance and an adequate procedure selected. The quality aspects of a technique include measurement range, analysis time, precision, noise, drift, bias, accuracy, resolution, sensitivity, lower detection limit, traceability, and investment and labor costs. A quantitative description for these aspects is given together with the major error sources. Altogether, it is advised to set up a protocol for each PSD measurement method in relation to the given application(s), in which all choices made are clearly described.
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…
Mathematical analysis of partial differential equations modeling electrostatic MEMS
Esposito, Pierpaolo; Guo, Yujin
2010-01-01
Micro- and nanoelectromechanical systems (MEMS and NEMS), which combine electronics with miniature-size mechanical devices, are essential components of modern technology. It is the mathematical model describing "electrostatically actuated" MEMS that is addressed in this monograph. Even the simplified models that the authors deal with still lead to very interesting second- and fourth-order nonlinear elliptic equations (in the stationary case) and to nonlinear parabolic equations (in the dynamic case). While nonlinear eigenvalue problems-where the stationary MEMS models fit-are a well-developed
Perfect harmony: A mathematical analysis of four historical tunings
Page, Michael F.
2004-10-01
In Western music, a musical interval defined by the frequency ratio of two notes is generally considered consonant when the ratio is composed of small integers. Perfect harmony or an ``ideal just scale,'' which has no exact solution, would require the division of an octave into 12 notes, each of which would be used to create six other consonant intervals. The purpose of this study is to analyze four well-known historical tunings to evaluate how well each one approximates perfect harmony. The analysis consists of a general evaluation in which all consonant intervals are given equal weighting and a specific evaluation for three preludes from Bach's ``Well-Tempered Clavier,'' for which intervals are weighted in proportion to the duration of their occurrence. The four tunings, 5-limit just intonation, quarter-comma meantone temperament, well temperament (Werckmeister III), and equal temperament, are evaluated by measures of centrality, dispersion, distance, and dissonance. When all keys and consonant intervals are equally weighted, equal temperament demonstrates the strongest performance across a variety of measures, although it is not always the best tuning. Given C as the starting note for each tuning, equal temperament and well temperament perform strongly for the three ``Well-Tempered Clavier'' preludes examined. .
Trude Nilsen; Carl Angell; Liv Sissel Grønmo
2013-01-01
As students advance in their learning of physics over the course of their education, the requirement of mathematical applications in physics-related tasks increases, especially so in upper secondary school and in higher education. Yet there is little empirical work (particularly large-scale or longitudinal) on the application of mathematics in physics education compared with the research related to the c...
Mathematical analysis of spontaneous emergence of cell polarity.
Lo, Wing-Cheong; Park, Hay-Oak; Chou, Ching-Shan
2014-08-01
Cell polarization, in which intracellular substances are asymmetrically distributed, enables cells to carry out specialized functions. While cell polarity is often induced by intracellular or extracellular spatial cues, spontaneous polarization (the so-called symmetry breaking) may also occur in the absence of spatial cues. Many computational models have been used to investigate the mechanisms of symmetry breaking, and it was proved that spontaneous polarization occurs when the lateral diffusion of inactive signaling molecules is much faster than that of active signaling molecules. This conclusion leaves an important question of how, as observed in many biological systems, cell polarity emerges when active and inactive membrane-bound molecules diffuse at similar rates while cycling between cytoplasm and membrane takes place. The recent studies of Rätz and Röger showed that, when the cytosolic and membrane diffusion are very different, spontaneous polarization is possible even if the membrane-bound species diffuse at the same rate. In this paper, we formulate a two-equation non-local reaction-diffusion model with general forms of positive feedback. We apply Turing stability analysis to identify parameter conditions for achieving cell polarization. Our results show that spontaneous polarization can be achieved within some parameter ranges even when active and inactive signaling molecules diffuse at similar rates. In addition, different forms of positive feedback are explored to show that a non-local molecule-mediated feedback is important for sharping the localization as well as giving rise to fast dynamics to achieve robust polarization.
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.
Mathematical foundations of neurocomputing
Energy Technology Data Exchange (ETDEWEB)
Amari, S. (Tokyo Univ. (Japan). Faculty of Engineering)
1990-09-01
Neurocomputing makes use of parallel dynamical interactions of modifiable neuron-like elements. It is important to show, by mathematical treatments, the capabilities and limitations of information processing by various architectures of neural networks. This paper, gives mathematical foundations to neurocomputing. It considers the capabilities of transformations by layered networks, statistical neurodynamics, the dynamical characteristics of associative memory, a general theory of neural learning, and self-organization of neural networks.
Body packing: a review of general background, clinical and imaging aspects.
Berger, Ferco H; Nieboer, Koenraad H; Goh, Gerard S; Pinto, Antonio; Scaglione, Mariano
2015-01-01
To avoid detection at border crossings or airport customs, drug trafficking is increasingly performed by intra-corporeal concealment. Body packers may ingest packets of varying size and containing varying drugs (mostly cocaine, heroin and cannabis) mixed with other compounds, while body pushers will insert packets in the rectum or vaginal cavity. Body packing may lead to potential life-threatening complications with acute overdose syndromes after packet rupture and intestinal obstruction with possible ensuing bowel rupture being the most significant complications. Physicians including radiologists should be aware of the capabilities of imaging techniques to screen for presence of drug packets as well as the potential complications. Although conventional radiography has long been and still is the most important imaging modality for screening for presence of intestinal packets, the better test characteristics in conjunction with the decreasing radiation exposure, will likely render computed tomography (CT) more important in the future. For imaging of symptomatic patients, CT already is the modality of choice. Besides these modalities, ultrasound and magnetic resonance imaging will be discussed in this paper, together with more general background and clinical information.
Topics in mathematical analysis and applications
Tóth, László
2014-01-01
This volume presents significant advances in a number of theories and problems of Mathematical Analysis and its applications in disciplines such as Analytic Inequalities, Operator Theory, Functional Analysis, Approximation Theory, Functional Equations, Differential Equations, Wavelets, Discrete Mathematics and Mechanics. The contributions focus on recent developments and are written by eminent scientists from the international mathematical community. Special emphasis is given to new results that have been obtained in the above mentioned disciplines in which Nonlinear Analysis plays a central role. Some review papers published in this volume will be particularly useful for a broader readership in Mathematical Analysis, as well as for graduate students. An attempt is given to present all subjects in this volume in a unified and self-contained manner, to be particularly useful to the mathematical community.
Time and space: the analysis of aspect in selected Spanish and Polish verbs of motion
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Cecylia Tatoj
2012-12-01
Full Text Available The objective of this article is to present how time and space are expressed, analyzing aspect in both Spanish and Polish. This issue is very complex, which is why we have decided to focus only on the description of selected verbs of motion – ir, venir and llegar in Spanish as well as iść and jechać in Polish. At the beginning of this work we outline the differences in the process of conceptualization of movement in both languages and then commenting on the concept of the aspect based on the semantic grammar approach proposed by Karolak (1984 and later works and developed and adapted by Wilk-Racięska (1995 and later works. Finally, the author discusses the aspect of the selected verbs of motion. It is also worth emphasizing that the problem of aspect is very important in expressing time in Polish, thus, a significant part of the work is dedicated to the analysis of the process of prefixation of verbs of motion in Polish as well as the resulting semantic changes. We look at 15 prefixes that can be added to Polish verbs iść and jechać and their derivatives. Dividing those prefixes in three general groups (prefixes that indicate approach, distance and prefixes that convey other types of information regarding the directionality, the author gives examples and describes the type of movement those prefixes imply.
Wada, B. K.; Kuo, C-P.; Glaser, R. J.
1986-01-01
For the structural dynamic analysis of large space structures, the technology in structural synthesis and the development of structural analysis software have increased the capability to predict the dynamic characteristics of the structural system. The various subsystems which comprise the system are represented by various displacement functions; the displacement functions are then combined to represent the total structure. Experience has indicated that even when subsystem mathematical models are verified by test, the mathematical representations of the total system are often in error because the mathematical model of the structural elements which are significant when loads are applied at the interconnection points are not adequately verified by test. A multiple test concept, based upon the Multiple Boundary Condition Test (MBCT), is presented which will increase the accuracy of the system mathematical model by improving the subsystem test and test/analysis correlation procedure.
FINANCING ASPECTS OF THE HUNGARIAN GENERAL MANUFACTURERS IN 2010-2012
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Herczeg Adrienn
2014-07-01
Full Text Available Observing and analysing the capital structure of corporations is one of the most important economic issue, it affects several fields of the life. The aim of the present study is to analyse the connection between capital structure and profitability in order to reveal such a ratio for the capital leverage and liabilities, by which it can say, to that connect the profit or loss. I searched the volume of influence of chosen indices of capital structure on financial and profit situation of corporations, in addition I studied which variant of those that take a part in development of capital structure, should be in functional relation with profitability indices. I used cutpoint analyses to determine the quantile point between the profitable or the non profitable operating. In my analysis I am seeking the answer for the question: whether the relation between the capital structure and the profitability can be proven, and if yes, then can we determine its direction and intensity.
A General Contact Force Analysis of an Under-actuated Finger in Robot Hand Grasping
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Xuan Vinh Ha
2016-02-01
Full Text Available This paper develops a mathematical analysis of contact forces for the under-actuated finger in a general under-actuated robotic hand during grasping. The concept of under-actuation in robotic grasping with fewer actuators than degrees of freedom (DOF, through the use of springs and mechanical limits, allows the hand to adjust itself to an irregularly shaped object without complex control strategies and sensors. Here the main concern is the contact forces, which are important elements in grasping tasks, based on the proposed mathematical analysis of their distributions of the n-DOF under-actuated finger. The simulation results, along with the 3-DOF finger from the ADAMS model, show the effectiveness of the mathematical analysis method, while comparing them with the measured results. The system can find magnitudes of the contact forces at the contact positions between the phalanges and the object.
Computational aspects of sensitivity calculations in transient structural analysis
Greene, William H.; Haftka, Raphael T.
1988-01-01
A key step in the application of formal automated design techniques to structures under transient loading is the calculation of sensitivities of response quantities to the design parameters. This paper considers structures with general forms of damping acted on by general transient loading and addresses issues of computational errors and computational efficiency. The equations of motion are reduced using the traditional basis of vibration modes and then integrated using a highly accurate, explicit integration technique. A critical point constraint formulation is used to place constraints on the magnitude of each response quantity as a function of time. Three different techniques for calculating sensitivities of the critical point constraints are presented. The first two are based on the straightforward application of the forward and central difference operators, respectively. The third is based on explicit differentiation of the equations of motion. Condition errors, finite difference truncation errors, and modal convergence errors for the three techniques are compared by applying them to a simple five-span-beam problem. Sensitivity results are presented for two different transient loading conditions and for both damped and undamped cases.
Computational Aspects of Equilibria
Yannakakis, Mihalis
Equilibria play a central role in game theory and economics. They characterize the possible outcomes in the interaction of rational, optimizing agents: In a game between rational players that want to optimize their payoffs, the only solutions in which no player has any incentive to switch his strategy are the Nash equilibria. Price equilibria in markets give the prices that allow the market to clear (demand matches supply) while the traders optimize their preferences (utilities). Fundamental theorems of Nash [34] and Arrow-Debreu [2] established the existence of the respective equilibria (under suitable conditions in the market case). The proofs in both cases use a fixed point theorem (relying ultimately on a compactness argument), and are non-constructive, i.e., do not yield an algorithm for constructing an equilibrium. We would clearly like to compute these predicted outcomes. This has led to extensive research since the 60’s in the game theory and mathematical economics literature, with the development of several methods for computation of equilibria, and more generally fixed points. More recently, equilibria problems have been studied intensively in the computer science community, from the point of view of modern computation theory. While we still do not know definitely whether equilibria can be computed in general efficiently or not, these investigations have led to a better understanding of the computational complexity of equilibria, the various issues involved, and the relationship with other open problems in computation. In this talk we will discuss some of these aspects and our current understanding of the relevant problems. We outline below the main points and explain some of the related issues.
Exploring Social Equity Aspects in Integrating Technology in Primary Mathematics Education
Stoilescu, Dorian
2014-01-01
This research focus on aspects of equity related to the introduction of using technology in classrooms. Technology has the potential to support mathematics pedagogy with visual representations and offer modelling and simulation facilities, increasing the creativity of the learning and teaching processes (Kaput, Ness, & Hoyles, 2008; Stoilescu…
Continuous cardiac output measurement - Aspects of Doppler frequency analysis
Mackay, R. S.; Hechtman, H. B.
1975-01-01
From the suprasternal notch blood flow velocity in the aorta can be measured non-invasively by a Doppler probe. Integration over systole after frequency analysis gives a measure of stroke volume if a separate diameter observation is incorporated. Frequency analysis by a zero crossing counter or by a set of parallel phaselock loops was less effective than a set of bandpass filters. Observations on dogs, baboons and humans before and after exercise or surgery suggest the indications to be useful. Application to judging heart failure by the effect of introducing a volume load is indicated. Changes in output also are measured in freely moving subjects.
COMPARATIVE ANALYSIS OF INNOVATION ASPECT EVIDENCE IN CONSTRUCTION AND MULTI-SECTOR COMPANIES
Ricardo Floriani; Ilse Maria Beuren; Nelson Hein
2010-01-01
The goal of this study is to make a comparative analysis of innovation aspect evidence among construction and multi-sector companies. Descriptive research was done through a content analysis of administration reports from 2005 to 2007. From the researched material, 14 aspects of innovations were extracted, which offer the basis to the content analysis. Two non-probability samples were developed, the first consisting of 22 multi-sector businesses, within 18 economic sectors, which comprises th...
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…
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)
General aspects of the nucleon-nucleon interaction and nuclear matter properties
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Plohl, Oliver
2008-07-25
The subject of the present thesis is at first the investigation of model independent properties of the nucleon-nucleon (NN) interaction in the vacuum concerning the relativistic structure and the implications for nuclear matter properties. Relativistic and non-relativistic meson-exchange potentials, phenomenological potentials s well as potentials based on effective field theory (EFT) are therefore mapped on a relativistic operator basis given by the Clifford Algebra. This allows to compare the various approaches at the level of covariant amplitudes where a remarkable agreement is found. Furthermore, the relativistic self-energy is determined in the Hartree-Fock (HF) approximation. The appearance of a scalar and vector field of several hundred MeV magnitude is a general feature of relativistic descriptions of nuclear matter. Within QCD sum rules these fields arise due to the density dependence of chiral condensates. We find that independent of the applied NN interaction large scalar and vector fields are generated when the symmetries of the Lorentz group are restored. In the framework of chiral EFT (chEFT) it is shown, that these fields are generated by short-range next-to-leading order (NLO) contact terms, which are connected to the spin-orbit interaction. To estimate the effect arising from NN correlations the equation of state of nuclear and neutron matter is calculated in the Brueckner-HF (BHF) approximation applying chEFT. Although, as expected, a clear over-binding is found (at NLO a saturating behavior is observed), the symmetry energy shows realistic properties when compared to phenomenological potentials (within the same approximation) and other approaches. The investigation of the pion mass dependence within chEFT at NLO shows that the magnitude of the scalar and vector fields persists in the chiral limit - nuclear matter is still bound. In contrast to the case of a pion mass larger than the physical one the binding energy and saturation density are
Some Aspects Regarding the Analysis of the Life Insurance Market
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Constantin Anghelache
2009-03-01
Full Text Available This paper aims to draw-up an analysis of the life insurance market in Romania. This survey is drawn up for the period 2003-2006 and the data used for this analysis were taken over from the Annual Reports published by the Insurance Supervision Commission. Life insurance market in Romania is a steady growing market as a result of the economic growth and the purchase power but is still far away from the development stage of the European markets.
Some aspects of analysis related to p-adic numbers
Semmes, Stephen
2014-01-01
A field with an absolute value function is a basic type of metric space, which includes the real and complex numbers with their standard metrics, and ultrametrics on fields like the p-adic numbers. Here we try to give some perspectives of analysis in situations like these.
Bardhan, Jaydeep P; Knepley, Matthew G
2011-09-28
We analyze the mathematically rigorous BIBEE (boundary-integral based electrostatics estimation) approximation of the mixed-dielectric continuum model of molecular electrostatics, using the analytically solvable case of a spherical solute containing an arbitrary charge distribution. Our analysis, which builds on Kirkwood's solution using spherical harmonics, clarifies important aspects of the approximation and its relationship to generalized Born models. First, our results suggest a new perspective for analyzing fast electrostatic models: the separation of variables between material properties (the dielectric constants) and geometry (the solute dielectric boundary and charge distribution). Second, we find that the eigenfunctions of the reaction-potential operator are exactly preserved in the BIBEE model for the sphere, which supports the use of this approximation for analyzing charge-charge interactions in molecular binding. Third, a comparison of BIBEE to the recent GBε theory suggests a modified BIBEE model capable of predicting electrostatic solvation free energies to within 4% of a full numerical Poisson calculation. This modified model leads to a projection-framework understanding of BIBEE and suggests opportunities for future improvements.
A Critical Discourse Analysis of a Real-World Problem in Mathematics: Looking for Signs of Change
Le Roux, Kate
2008-01-01
The concepts of "access" and "relevance" feature prominently in the discourse of change in mathematics education in South Africa. One way in which these concepts have been played out in mathematics classrooms is in the use of mathematical problems with real-world contexts. This paper presents a Critical Discourse Analysis of…
A Critical Discourse Analysis of a Real-World Problem in Mathematics: Looking for Signs of Change
Le Roux, Kate
2008-01-01
The concepts of "access" and "relevance" feature prominently in the discourse of change in mathematics education in South Africa. One way in which these concepts have been played out in mathematics classrooms is in the use of mathematical problems with real-world contexts. This paper presents a Critical Discourse Analysis of…
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.
Blein, G; Azorin, J M; Vollrath, J L; Andréoli, A; Tissot, R
1987-05-01
Paranoid schizophrenics are unable to balance affirmation and negation. Using the terms of Jean Piaget, they therefore only partially achieve the "équilibrations majorantes" of level II and never those of level III. In their thinking, they have access to the "généralisations inductives" (often excessive ones), but rarely to the "généralisations constructives complétives". They do not have access to the "généralisations synthétisantes" or to the feeling that logic is necessary. They oscillate between the positivist need to measure or verify and absolute beliefs issued from magical thinking.
Problems of Economic Grown in Modern Russia: General Characteristics and Regional Aspect
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Sergey N. Levin
2016-12-01
Full Text Available Authors analyze the problem to find the optimal policy options to stimulate economic growth in modern conditions. They point out three possible options for such policy according to the different structural priorities. This point causes the question of the extent to which the proposed policy approaches to stimulate economic growth correspond to real economic trends. The solution of this problem is possible only on the basis of the empirical study analysis results. Also it is necessary to take into account the regional dimension related to the fact that the various sectors of the economy linked to the various regions. According to this fact one may point out Russian regions with the predominance of the mining industry, manufacturing industry and services. Authors exploit panel dataset on 80 Russian regions for the period 2005-2014 to analyze the relationship between annual shares of sectors in output and employment and per capita gross regional growth. Results indicate that regions with a higher share of manufacturing and mining both in terms of output and employment grow slower during the reporting period. The impact of services on growth is somewhat paradoxical: regions with bigger shares of healthcare and education in output growth faster, but a bigger share of this sector in employment, as much as expanding of the labor share of these sectors impede growth. Possible reason for this paradox is that the high proportion of services in the regions-leaders (especially the share of total employment reflects not the degree of their development, but the development of the public sector in relatively poor regions. The results show that neither manufacturing nor mining and services are not the engines of economic growth that can ensure sustainable development of the whole economy. Authors point out that it is necessary to conduct multivariate policies to stimulate economic growth, which is based on the various configurations of developmental actors
Verification of temporal-causal network models by mathematical analysis
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Jan Treur
2016-04-01
Full Text Available Abstract Usually dynamic properties of models can be analysed by conducting simulation experiments. But sometimes, as a kind of prediction properties can also be found by calculations in a mathematical manner, without performing simulations. Examples of properties that can be explored in such a manner are: whether some values for the variables exist for which no change occurs (stationary points or equilibria, and how such values may depend on the values of the parameters of the model and/or the initial values for the variables whether certain variables in the model converge to some limit value (equilibria and how this may depend on the values of the parameters of the model and/or the initial values for the variables whether or not certain variables will show monotonically increasing or decreasing values over time (monotonicity how fast a convergence to a limit value takes place (convergence speed whether situations occur in which no convergence takes place but in the end a specific sequence of values is repeated all the time (limit cycle Such properties found in an analytic mathematical manner can be used for verification of the model by checking them for the values observed in simulation experiments. If one of these properties is not fulfilled, then there will be some error in the implementation of the model. In this paper some methods to analyse such properties of dynamical models will be described and illustrated for the Hebbian learning model, and for dynamic connection strengths in social networks. The properties analysed by the methods discussed cover equilibria, increasing or decreasing trends, recurring patterns (limit cycles, and speed of convergence to equilibria.
Mathematics of uncertainty modeling in the analysis of engineering and science problems
Chakraverty, S
2014-01-01
For various scientific and engineering problems, how to deal with variables and parameters of uncertain value is an important issue. Full analysis of the specific errors in measurement, observations, experiments, and applications are vital in dealing with the parameters taken to simplify the problem. Mathematics of Uncertainty Modeling in the Analysis of Engineering and Science Problems aims to provide the reader with basic concepts for soft computing and other methods for various means of uncertainty in handling solutions, analysis, and applications. This book is an essential reference work for students, scholars, practitioners and researchers in the assorted fields of engineering and applied mathematics interested in a model for uncertain physical problems.
Analysis of response rates during stimulus generalization.
Migler, B; Millenson, J R
1969-01-01
In the presence of one click frequency, the presses of two hungry rats on one of two levers were reinforced with food on variable-interval schedules; in the presence of a different click frequency, presses on the other lever were reinforced. In stimulus generalization tests, a variety of click frequencies were presented and reinforcement withheld. The test stimuli were found to exert control over which of the two levers the rats pressed, but not over the rate of pressing the selected lever. The results were interpreted as further evidence that intermediate rates in generalization gradients may be the result of the alternation of several distinct behavior patterns.
Analysis of Science and Mathematics Education Articles Published In Turkey-I: Keywords
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Enver TATAR
2008-01-01
Full Text Available In this study, a descriptive analysis of science and mathematics education articlespublished in Turkey was purposed. The study was carried out based on the keywords ofa total of 680 articles which were published in 26 refereed journals during 2000-2006.As a result of the analysis of the data obtained from the study, the following werefound: (a there were keywords including up to eight words, almost in the form of asentence (b The frequencies of nearly all keywords related to topics in the curriculumof science and mathematics were low c Science and mathematics topics in thecurriculum of primary school were studied less than topics in secondary and universitylevel (d Studies related to the misconceptions in the science education and related toattitude the mathematics education were mostly studied by researchers.
Lin, Su-Wei; Tai, Wen-Chun
2015-01-01
This study investigated how various mathematics learning strategies affect the mathematical literacy of students. The data for this study were obtained from the 2012 Programme for International Student Assessment (PISA) data of Taiwan. The PISA learning strategy survey contains three types of learning strategies: elaboration, control, and…
Kalanov, Temur Z.
2015-04-01
Analysis of the foundations of standard trigonometry is proposed. The unity of formal logic and of rational dialectics is methodological basis of the analysis. It is shown that the foundations of trigonometry contradict to the principles of system approach and contain formal-logical errors. The principal logical error is that the definitions of trigonometric functions represent quantitative relationships between the different qualities: between qualitative determinacy of angle and qualitative determinacy of rectilinear segments (legs) in rectangular triangle. These relationships do not satisfy the standard definition of mathematical function because there are no mathematical operations that should be carry out on qualitative determinacy of angle to obtain qualitative determinacy of legs. Therefore, the left-hand and right-hand sides of the standard mathematical definitions have no the identical sense. The logical errors determine the essence of trigonometry: standard trigonometry is a false theory.
A Historical Analysis of Primary Mathematics Curricula in Terms of Teaching Principles
Ozmantar, Mehmet Fatih
2017-01-01
This study carries out a comparative analysis of primary mathematics curricula put into practice during Turkish Republican period. The data for this study are composed of official curricula documents which are examined in terms of teaching principles. The study adopts a qualitative approach and employs document analysis method. The official…
Robert, Aline
1995-01-01
Examines discourse, not strictly mathematical, that teachers might adopt in a mathematics class and presents three major functions of such discourse: communication; structuring and labeling; and reflection. Develops lines for further inquiry, notably on the third function, the most likely focus for specific preparation by the teacher. (13…
Mohammadi, Bijan; Pironneau, Olivier; Cipolla, Vittorio
2016-01-01
This book presents papers surrounding the extensive discussions that took place from the ‘Variational Analysis and Aerospace Engineering’ workshop held at the Ettore Majorana Foundation and Centre for Scientific Culture in 2015. Contributions to this volume focus on advanced mathematical methods in aerospace engineering and industrial engineering such as computational fluid dynamics methods, optimization methods in aerodynamics, optimum controls, dynamic systems, the theory of structures, space missions, flight mechanics, control theory, algebraic geometry for CAD applications, and variational methods and applications. Advanced graduate students, researchers, and professionals in mathematics and engineering will find this volume useful as it illustrates current collaborative research projects in applied mathematics and aerospace engineering.
Mathematical Text Processing in EA-style: a Sequent Aspect
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Alexander Lyaletski
2016-01-01
Full Text Available The paper is devoted to the study of one of the aspects of the so-called Evidence Algorithm programme advanced by Academician V.M.~Glushkov and connected with the problem of automated theorem-proving search in the signature of first-order theories that can use different logics, such as classical, intuitionistic, and modal ones. An approach to the construction of such sequent logics (with or without equality is described. It exploits the original notions of admissibility and compatibility, which permits to avoid preliminary skolemization being a forbidden operation for a number of non-classical logics in general. Following the approach, the cut-free sequent (modal calculi avoiding the dependence of inference search on different orders of quantifier rules applications are described. Results on the coextensivity of sequent calculi are given. The research gives a way to the construction of computer-oriented quantifier-rule-free calculi for classical and intuitionistic logics and their modal extensions.
Psychomotor education, an aspect of general formation of pre-school children
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Ardian Shingjergji
2013-06-01
Full Text Available Current developments of scientific thinking in the field of education are increasingly demanding in various disciplines for young people as a matter of urgency. It is already known that child development is conditioned by ancestry, socio-cultural environment, including interaction with peers and adults. Albanian institutions (kindergarten compared to contemporary experience in more developed countries have to deal with issues such as: (1 The development of a run or optimal acceleration enrichment motor for kindergarten children, seen as an important element of the formation of the human personality and its preparation to cope with various situations of life ; (2 The role of infrastructure in the natural development of the personality of children and the educational process as a whole; (3 Parental community involvement as a fundamental prerequisite of real development of the child; (4The qualification level of the teaching staff in the elementary education system and the preparation of students teacher. I hope to add my contribution through this paper, not only by identifying the problems above, but also in presenting alternatives of a development model of kindergarten children motors skills progress, compared to contemporary experience in more developed countries. Keywords: ; ; ; ;
General aspects and current view of the molecular study of Phenylketonuria (PKU in Mexico
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Miguel Ángel Alcántara-Ortigoza
2014-07-01
Full Text Available Phenylketonuria (PKU is an autosomic recessive inborn errors of metabolism. It is caused y the deficiency of phenylalanine hydroxylase, an enzyme encoded by the PAH gene in 12q22. This gene has a wide mutation spectrum and several different genotypes have been identified. There are many experimental strategies that allow molecular diagnosis of PAH in order to identify causal mutations in patients with phenylektonuria. The identification of the PAH genotype in these patients allows genetic counseling, genotype-phenotype correlation and for some cases treatment adjustment. There are few studies concerning the mutation spectrum of PAH in Mexican patients. Currently, a study to identify the genotypes of these patients is being done. Only preliminary results are presented, nevertheless results are expected to clarify the mutation spectrum, enable the identification of possible genotype-phenotype correlations and elucidate the ancestral origin of the mutations.
DEFF Research Database (Denmark)
Vass, M; Hendriksen, C
2005-01-01
people and to consider different approaches when evaluating evidence of risk and benefit for the individual. Old people are facing a considerable risk of adverse drug reactions and recent initiatives, including the Continuous Medical Educational Efforts Programme, address issues of inappropriate...... state that a number of pharmacological regimens for older people are outperformed by non-pharmacological treatment alternatives involving competent individualised counselling and public provision of easy (transportation) possibilities for joining centres offering staff and equipment for physical......This paper discusses GP perspectives on the principles underlying rational pharmacotherapy for older people. The rising use of prescription medicine forces the GP to balance the benefit of evidence group-based appropriate drug use against the problems arising when medication is given to older...
[Psychotic disorders: special aspects in general practice].
Kurmann, Julius
2015-09-30
In emergency situations the general practitioner is often the first professional contact psychotic patients have. The following article conveys basic knowledge about psychotic disorders and their clinical features typically seen in general practice.
DEFF Research Database (Denmark)
Videbæk Le, Jette; Pedersen, Line Bjørnskov; Riisgaard, Helle
2017-01-01
questionnaire was distributed to GPs, and data on spirometry testing among first-time users of medication against obstructive lung diseases were obtained from national registers. Associations were investigated using multilevel mixed-effect logit models. Results GPs from 1,114 practices (58%) responded, and 33...
Thomaseth, K
1994-02-14
Software is presented for automatic generation of first-order ordinary differential equations (ODE) that arise from lumped parameter representations of metabolic and pharmacokinetic systems. The definition of system structures is accomplished by fractional transfer rates between state variables, together with input/output equations and initial conditions of state variables. General non-linear mathematical expressions can be assigned to all structure definition items. The software parses and interprets the system definitions and generates symbolically the mathematical expression of the model's set of ODE. In addition, symbolic derivatives of state equations are determined with respect to model parameters, state variables and external inputs. These derivatives represent the constituents of systems of sensitivity-differential and adjoint-differential equations that arise in identification and optimal control problems. Finally, output routines generate source code that, once compiled and linked to simulation programs, allows efficient numerical integration of the system of ODE. This software has been developed in PROLOG on Macintosh computers and has been extensively used with the programming environment MATLAB. Possible applications of this software include model building, sensitivity analysis, identification, optimal experiment design and numerical solution of optimal control problems.
Mathematical theory of compressible fluid flow
Von Mises, Richard
2012-01-01
Mathematical Theory of Compressible Fluid Flow covers the conceptual and mathematical aspects of theory of compressible fluid flow. This five-chapter book specifically tackles the role of thermodynamics in the mechanics of compressible fluids. This text begins with a discussion on the general theory of characteristics of compressible fluid with its application. This topic is followed by a presentation of equations delineating the role of thermodynamics in compressible fluid mechanics. The discussion then shifts to the theory of shocks as asymptotic phenomena, which is set within the context of
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Abdulkadir ERDOĞAN
2012-03-01
exhibition. However, more than a half of visitors, some of them also indicated a general appreciation, used expressions in the meaning of the popularization of mathematics. According to the categories carried out, these expressions were identified as related to the potentiality of the exhibition (1 to address a large mass of people, (2 to show the concrete and experimental aspect of mathematics, (3 to show the fun and attractive aspect of mathematics, (4 to contribute to the creative and analytical thinking, (5 to show the relation between mathematics and daily life, (6 to contribute to change views and attitudes towards mathematics. The content analysis indicated that the visitors’ expressions were full of authentic feelings and opinions about the exhibition, although they mostly concerned the potentiality of the exhibition to change views and attitudes towards mathematics. On the other hand, five visitors wrote down negative comments but only one of them concerned the content of the exhibition. Discussion: The great and increasing number of visitors, and the distribution of this number among people of different ages, from the preschool children to parents, can be considered as a result of the potentiality of the exhibition to address a large masse, and as a result of its positive effect on the visitors. The visitors’ general appreciations and acknowledgements, and the happiness and surprise expressed by some visitors support this positive effect of the exhibition. In addition, the fact that the visitors’ views were not limited to general appreciations and acknowledgements, and that 186 visitors wrote down various opinions or expressed authentic feelings within the categories describe above can be considered as due to the potentiality of the exhibition for the popularization of mathematics, in particular, to change views and attitudes towards mathematics. On the other hand, the fact that the number of negative opinions were limited to a very few comments can be
Surface analysis of transition metal oxalates: Damage aspects
Energy Technology Data Exchange (ETDEWEB)
Chenakin, S.P., E-mail: chenakin@imp.kiev.ua [Université Libre de Bruxelles (ULB), Chimie-Physique des Matériaux, B-1050 Bruxelles (Belgium); Institute of Metal Physics, Nat. Acad. Sci. of Ukraine, Akad. Vernadsky Blvd. 36, 03680 Kiev (Ukraine); Szukiewicz, R. [Université Libre de Bruxelles (ULB), Chimie-Physique des Matériaux, B-1050 Bruxelles (Belgium); Barbosa, R.; Kruse, N. [Université Libre de Bruxelles (ULB), Chimie-Physique des Matériaux, B-1050 Bruxelles (Belgium); Voiland School of Chemical Engineering and Bioengineering, Washington State University, 155 Wegner Hall, Pullman, WA 99164-6515 (United States)
2016-05-15
Highlights: • Gas evolution from the Mn, Co, Ni and Cu oxalate hydrates in vacuum, during exposure to X-rays and after termination of X-ray irradiation is studied. • A comparative study of the damage caused by X-rays in NiC{sub 2}O{sub 4} and CuC{sub 2}O{sub 4} is carried out. • Effect of Ar{sup +} bombardment on the structure and composition of CoC{sub 2}O{sub 4} is studied. - Abstract: The behavior of transition metal oxalates in vacuum, under X-ray irradiation and low-energy Ar{sup +} ion bombardment was studied. A comparative mass-spectrometric analysis was carried out of gas evolution from the surface of Mn, Co, Ni and Cu oxalate hydrates in vacuum, during exposure to X-rays and after termination of X-ray irradiation. The rates of H{sub 2}O and CO{sub 2} liberation from the oxalates were found to be in an inverse correlation with the temperatures of dehydration and decomposition, respectively. X-ray photoelectron spectroscopy (XPS) was employed to study the X-ray induced damage in NiC{sub 2}O{sub 4} and CuC{sub 2}O{sub 4} by measuring the various XP spectral characteristics and surface composition of the oxalates as a function of time of exposure to X-rays. It was shown that Cu oxalate underwent a significantly faster degradation than Ni oxalate and demonstrated a high degree of X-ray induced reduction from the Cu{sup 2+} to the Cu{sup 1+} chemical state. 500 eV Ar{sup +} sputter cleaning of CoC{sub 2}O{sub 4} for 10 min was found to cause a strong transformation of the oxalate structure which manifested itself in an appreciable alteration of the XP core-level and valence band spectra. The analysis of changes in stoichiometry and comparison of XP spectra of bombarded oxalate with respective spectra of a reference carbonate CoCO{sub 3} implied that the bombardment-induced decomposition of CoC{sub 2}O{sub 4} gave rise to the formation of CoO-like and disordered CoCO{sub 3}-like phases.
Some aspects of implementing Regulatory Impact Analysis in Brazil
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Camila Moreira de Castro
2014-04-01
Full Text Available In an increasingly complex society, regulatory polices emerge as an important tool in public management. Nevertheless, regulation per se is no longer enough, and the agenda for a regulatory reform is increasing. Following this context, Brazil has implemented Regulatory Impact Analysis (RIA in its regulatory agencies. Thus, Brazilian specificities have to be considered and, in this regard, a systematic approach provides a significant contribution. This article aims to address some critical reflections about which policy-makers should ask themselves before joining the implementation of a RIA system in the Brazilian context. Through a long-term perspective, the implementation of RIA must be seen as part of a permanent change in the administrative culture, understanding that RIA should be used as a further resource in the decision-making process, rather than a final solution.
Algebraic aspects of gauge theories
Zharinov, V. V.
2014-08-01
Gauge theories are primary tools in modern elementary particle physics. The generally recognized mathematical foundations of these theories are in differential geometry, namely, in the theory of connections in a principal fiber bundle. We propose another approach to the mathematical description of gauge theories based on a combination of algebraic and geometric methods.
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.
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).
Mathematical analysis of a model for glucose regulation.
Fessel, Kimberly; Gaither, Jeffrey B; Bower, Julie K; Gaillard, Trudy; Osei, Kwame; Rempala, Grzegorz A
2016-02-01
Diabetes affects millions of Americans, and the correct identification of individuals afflicted with this disease, especially of those in early stages or in progression towards diabetes, remains an active area of research. The minimal model is a simplified mathematical construct for understanding glucose-insulin interactions. Developed by Bergman, Cobelli, and colleagues over three decades ago, this system of coupled ordinary differential equations prevails as an important tool for interpreting data collected during an intravenous glucose tolerance test (IVGTT). In this study we present an explicit solution to the minimal model which allows for separating the glucose and insulin dynamics of the minimal model and for identifying patient-specific parameters of glucose trajectories from IVGTT. As illustrated with patient data, our approach seems to have an edge over more complicated methods currently used. Additionally, we also present an application of our method to prediction of the time to baseline recovery and calculation of insulin sensitivity and glucose effectiveness, two quantities regarded as significant in diabetes diagnostics.
A retrospective mathematical analysis of controlled release design and experimentation.
Rothstein, Sam N; Kay, Jennifer E; Schopfer, Francisco J; Freeman, Bruce A; Little, Steven R
2012-11-01
The development and performance evaluation of new biodegradable polymer controlled release formulations relies on successful interpretation and evaluation of in vitro release data. However, depending upon the extent of empirical characterization, release data may be open to more than one qualitative interpretation. In this work, a predictive model for release from degradable polymer matrices was applied to a number of published release data in order to extend the characterization of release behavior. Where possible, the model was also used to interpolate and extrapolate upon collected released data to clarify the overall duration of release and also kinetics of release between widely spaced data points. In each case examined, mathematical predictions of release coincide well with experimental results, offering a more definitive description of each formulation's performance than was previously available. This information may prove particularly helpful in the design of future studies, such as when calculating proper dosing levels or determining experimental end points in order to more comprehensively evaluate a controlled release system's performance.
GENERAL ASPECTS REGARDING THE PRIOR DISCIPLINARY RESEARCH
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ANDRA PURAN (DASCĂLU
2012-05-01
Full Text Available Disciplinary research is the first phase of the disciplinary action. According to art. 251 paragraph 1 of the Labour Code no disciplinary sanction may be ordered before performing the prior disciplinary research.These regulations provide an exception: the sanction of written warning. The current regulations in question, kept from the old regulation, provides a protection for employees against abuses made by employers, since sanctions are affecting the salary or the position held, or even the development of individual employment contract. Thus, prior research of the fact that is a misconduct, before a disciplinary sanction is applied, is an essential condition for the validity of the measure ordered. Through this study we try to highlight some general issues concerning the characteristics, processes and effects of prior disciplinary research.
The use of video analysis and the Knowledge Quartet in mathematics teacher education programmes
Liston, Miriam
2015-01-01
This study investigates the potential of video analysis and a mathematical knowledge for teaching framework, the Knowledge Quartet (KQ), in mathematics teacher education programmes. It reports on the effectiveness of these tools in analysing and supporting secondary level pre-service mathematics teachers' subject matter knowledge and pedagogical content knowledge. This paper describes how a videotaped lesson of one pre-service teacher, teaching a class of mature students, was analysed and makes comparisons between the teacher educators' and the pre-service teacher's observations. Inter-rater reliability was investigated and a Kappa coefficient of .72 indicated substantial agreement between both coders. Findings are presented and implications of the use of video and the KQ for mathematics teacher education are drawn.
Mathematical analysis, approximation theory and their applications
Gupta, Vijay
2016-01-01
Designed for graduate students, researchers, and engineers in mathematics, optimization, and economics, this self-contained volume presents theory, methods, and applications in mathematical analysis and approximation theory. Specific topics include: approximation of functions by linear positive operators with applications to computer aided geometric design, numerical analysis, optimization theory, and solutions of differential equations. Recent and significant developments in approximation theory, special functions and q-calculus along with their applications to mathematics, engineering, and social sciences are discussed and analyzed. Each chapter enriches the understanding of current research problems and theories in pure and applied research.
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Mikhailova N. V.
2016-01-01
Full Text Available The paper is devoted to the analysis and identification of new philosophical aspects of the problem of justification of modern mathematics according to which to the end of the 20th century the most exact of sciences had experienced new shocks associated with the crisis of excessive complexity of the mathematical theories. In the context of justification of mathematics philosophical conclusion consists in the fact that from a methodological point of view for general assessment of whether mathematics is developed or not just the lack of crises is more negative phenomenon than its too long trouble-free state. Accomplished fact is that a computer can be regarded as one of the serious revolutionary technological inventions of the last century, which has had a huge influence on mathematics. In this development of progress of contemporary mathematics, more precisely, in its instrumental technologies the new philosophical problems are revealed - this is the role of computers and the new standards of mathematical thinking. In addition, with the development of contemporary mathematics and the emergence of increasingly complicated and long proofs, they lose their methodological advantage - the property of visibility and convincingness. Within the philosophy of mathematics this problem has not been discussed yet, possibly because the leading mathematicians haven’t expressed their opinions on the subject. After that, we can wait for a methodologically important period clarifying details, which can make the process itself foundations of mathematics philosophical consummation as the crisis complexity; in mathematics it is not a “systemic crisis” carrying the potential danger of the destruction of all mathematical knowledge.
Dynamics of Love and Happiness: A Mathematical Analysis
Directory of Open Access Journals (Sweden)
Dharna Satsangi
2012-06-01
Full Text Available The human behavior is a combination of several feelings. There are two cases whether a person likes other individual or not. The liking of an individual leads to love and finally happiness. The feelings of love may be in different forms but here considered to be partners’ love. There are three aspects of love for the partner: forgetting process (oblivion, the pleasure of being loved (return, and the reaction to the appeal of the partner (instinct. Along with that the appeals and the personalities of the two individuals do not vary in time. This model proves that if the geometric mean reactive-ness to love is smaller than the geometric mean forgetting coefficient and the system is asymptotically stable if the ratio of appeals is greater than the reciprocal of ratio of mutual intensiveness coefficient.
Stress State Analysis in Aspect of Wellbore Drilling Direction
Knez, Dariusz
2014-03-01
Drilling directional wells challenges designers. Apart from known problems until now they face exact description of stress distribution in near wellbore region issue. Paper presents analysis of stress state taking into account drilling direction. The transposed in-situ stress state relative to the borehole coordinate system (Cartesian borehole coordinate system) and the total stress component at the borehole wall (cylindrical coordinate system) exhibits cyclic behaviour with respect to drilling direction of borehole. It allows to find optimal wellbore path Wiercenie otworów kierunkowych stanowi duże wyzwanie dla projektantów. Poza problemami typowymi obecnie staja oni w obliczu zagadnienia dokładnego opisu rozkładu naprężeń w strefie przyotworowej. Artykuł przedstawia analizę stanu naprężeń w aspekcie kierunku wiercenia. Rozkład naprężeń transponowany do układu odniesienia związanego z otworem wiertniczym (kartezjański układ współrzędnych zgodny z kierunkiem otworu wiertniczego) oraz składowe naprężenia na ścianie otworu wiertniczego (w cylindrycznym układzie odniesienia) wykazują cykliczną zmienność zależną od kierunku wiercenia. Pozwala to na określenie optymalnej trajektorii osi otworu wiertniczego
[Methodological aspects of a political-economic analysis of population].
Lisina, N V; Ruzavina, E I
1988-01-01
The authors examine the role of political and economic factors in the study of population issues, with a focus on the relationship between demographic factors and the standard of living of a society. Attention is paid to the division of the population into the economically active and the inactive.
A graph theoretical analysis of certain aspects of Bahasa Indonesia
Hoede, C.; Nurdiati, S.
2008-01-01
In this paper the theory of knowledge graphs is applied to some characteristic features of the Indonesian language. The characteristic features to be considered are active and passive form of verbs and the derived nouns
Envisioning migration: mathematics in both experimental analysis and modeling of cell behavior.
Zhang, Elizabeth R; Wu, Lani F; Altschuler, Steven J
2013-10-01
The complex nature of cell migration highlights the power and challenges of applying mathematics to biological studies. Mathematics may be used to create model equations that recapitulate migration, which can predict phenomena not easily uncovered by experiments or intuition alone. Alternatively, mathematics may be applied to interpreting complex data sets with better resolution--potentially empowering scientists to discern subtle patterns amid the noise and heterogeneity typical of migrating cells. Iteration between these two methods is necessary in order to reveal connections within the cell migration signaling network, as well as to understand the behavior that arises from those connections. Here, we review recent quantitative analysis and mathematical modeling approaches to the cell migration problem. Copyright © 2013 Elsevier Ltd. All rights reserved.
Experimental Analysis of Aerodynamic Aspects of Sport Utility Vehicle
Directory of Open Access Journals (Sweden)
DINESH Y DHANDE
2013-07-01
Full Text Available In an era fuel efficiency has become topic of discussion not only among the scholar researchers but also common men. As rapid and continuous increase in prizes of fuels consumers are going for most fuel efficient vehicles. By aerodynamic styling of vehicle one can not only improve the fuel efficiency but also ensure better stability and good handling characteristics of vehicles at higher speed especially on highways. The paper describes assessment of drag force (Fd and drag coefficient (Cd by conventional wind tunnel method. Theexperimental calculations were performed on subsonic wind tunnel having test section of 100cm x 30cm x 30 cm. Exact replica of model of sports utility vehicle (suv on reduced scale 1:32 is used to for experimentation to calculate Fd and Cd.
Mathematical Analysis of Queue with Phase Service: An Overview
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Richa Sharma
2014-01-01
Full Text Available We discuss various aspects of phase service queueing models. A large number of models have been developed in the area of queueing theory incorporating the concept of phase service. These phase service queueing models have been investigated for resolving the congestion problems of many day-to-day as well as industrial scenarios. In this survey paper, an attempt has been made to review the work done by the prominent researchers on the phase service queues and their applications in several realistic queueing situations. The methodology used by several researchers for solving various phase service queueing models has also been described. We have classified the related literature based on modeling and methodological concepts. The main objective of present paper is to provide relevant information to the system analysts, managers, and industry people who are interested in using queueing theory to model congestion problems wherein the phase type services are prevalent.
Directory of Open Access Journals (Sweden)
Muhammad Rafi
2015-10-01
Full Text Available It is very common for a customer to read reviews about the product before making a final decision to buy it. Customers are always eager to get the best and the most objective information about the product theywish to purchase and reviews are the major source to obtain this information. Although reviews are easily accessible from the web, but since most of them carry ambiguous opinion and different structure, it is often very difficult for a customer to filter the information he actually needs. This paper suggests a framework, which provides a single user interface solution to this problem based on sentiment analysis of reviews. First, it extracts all the reviews from different websites carrying varying structure, and gathers information about relevant aspects of that product. Next, it does sentiment analysis around those aspects and gives them sentiment scores. Finally, it ranks all extracted aspects and clusters them into positive and negative class. The final output is a graphical visualization of all positive and negative aspects, which provide the customer easy, comparable, and visual information about the important aspects of the product. The experimental results on five different products carrying 5000 reviewsshow 78% accuracy. Moreover, the paper also explained the effect of Negation, Valence Shifter, and Diminisher with sentiment lexiconon sentiment analysis, andconcluded that they all are independent of the case problem , and have no effect on the accuracy of sentiment analysis.
Assessment of occupational exposure to pesticides in agriculture : Pt 1 General aspects
Hemmen, J.J. van
1992-01-01
For registration of pesticides data on toxicology and on occupational exposure are required. In this series of reviews the exposure data available in the published literature for mixing and loading, application and re-entry are considered for the establishment of generic/surrogate data bases with wh
General Aspects about the Martensitic Transformation
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Edwar A. Torres-López
2013-11-01
Full Text Available With the time, the number of studies associated to the martensitic transformation has been expanded; therefore, understand as this mechanism operates and as it confers different characteristics to diverse materials where it occurs, many studies has been conducted in different areas carrying out to discoveries at microstructural, kinetic and crystallographic level. This paper presents an overview of the martensitic transformation, beginning with a historical development, through a review on their morphology and kinetically characteristics, in addition to an analysis of the prospects of the studies carried out in the area, with a special interest in the phenomena of thermo-elasticity and shape memory.
A Comparative Analysis of Selected Aspects of the
African Journals Online (AJOL)
10332324
REGULATING TRADITIONAL JUSTICE IN SOUTH AFRICA: A. COMPARATIVE ... See the Traditional Leadership and Governance Framework Act 41 of 2003 and the Traditional .... must therefore not be in conflict with the Constitution. When it ...
Cross-sectional analysis of psychological aspects of adolescent underachievers
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Sanjay Kumar Nayak
2010-01-01
Full Text Available Background: Previous research supports that factors commonly associated with underachievement include low academic self-concept, low self-efficacy, low self-motivation, low goal valuation and negative attitude toward school and teachers. Purpose: The purpose of this study was to assess the feeling about reading of adolescent underachievers, including emotional difficulties, physical problem (usually eye dysfunction, mechanism of reading, self-concept, and interest in reading. Materials and Methods: Forty-eight underachievers were compared with 40 achievers from 6 to 10 standard students on "My feeling about reading" checklist. Hypotheses were tested using t-test and χ2 (chi-square test through statistical package for the social sciences. Results: The result suggests that underachievers significantly differ from achievers in all five domains, i.e. emotional difficulties, physical problems (usually eye dysfunction, mechanism of reading, self-concept, and interest in learning. Conclusion: Underachievers face different emotional and other psychological difficulties during their academic sessions. They must be taken care of properly within their academic environment.
Jalvingh, A.W.; Dijkhuizen, A.A.; Arendonk, van J.A.M.
1992-01-01
A dynamic probabilistic model has been designed for the personal computer to determine the technical and economic consequences of various biological variables and management strategies concerning reproduction and replacement in swine. In it, the Markov chain approach is used to simulate herd
TU-F-201-01: General Aspects of Radiochromic Film Dosimetry
Energy Technology Data Exchange (ETDEWEB)
Niroomand-Rad, A.
2015-06-15
Since the introduction of radiochromic films (RCF) for radiation dosimetry, the scope of RCF dosimetry has expanded steadily to include many medical applications, such as radiation therapy and diagnostic radiology. The AAPM Task Group (TG) 55 published a report on the recommendations for RCF dosimetry in 1998. As the technology is advancing rapidly, and its routine clinical use is expanding, TG 235 has been formed to provide an update to TG-55 on radiochromic film dosimetry. RCF dosimetry applications in clinical radiotherapy have become even more widespread, expanding from primarily brachytherapy and radiosurgery applications, and gravitating towards (but not limited to) external beam therapy (photon, electron and protons), such as quality assurance for IMRT, VMAT, Tomotherapy, SRS/SRT, and SBRT. In addition, RCF applications now extend to measurements of radiation dose in particle beams and patients undergoing medical exams, especially fluoroscopically guided interventional procedures and CT. The densitometers/scanners used for RCF dosimetry have also evolved from the He-Ne laser scanner to CCD-based scanners, including roller-based scanner, light box-based digital camera, and flatbed color scanner. More recently, multichannel RCF dosimetry introduced a new paradigm for external beam dose QA for its high accuracy and efficiency. This course covers in detail the recent advancements in RCF dosimetry. Learning Objectives: Introduce the paradigm shift on multichannel film dosimetry Outline the procedures to achieve accurate dosimetry with a RCF dosimetry system Provide comprehensive guidelines on RCF dosimetry for various clinical applications One of the speakers has a research agreement from Ashland Inc., the manufacturer of Gafchromic film.
An introduction to mathematical analysis
Shirali, Satish
2014-01-01
This book is an elementary text on the theory of functions of one real variable and is intended for students with a good understanding of calculus. It is supposed to replace traditional and outmoded courses in mathematical analysis. The book begins with material on the real number system as a Dedekind complete ordered field, continuous functions, sequences and series of constant terms as well as of functions. Pointwise and uniform convergence of series of functions, power series, treatment of trigonometric and exponential functions in terms of series are discussed. A detailed treatment of differentiation, including differentiation of uniform limits of sequences is provided. Also included is an example of a continuous nowhere differentiable function. There is an exhaustive treatment of both Riemann integration and Riemann-Stieltjes integration. Some features of this work, such as why Dedekind completeness is necessary for ensuring that nonconstant functions cannot have derivative zero everywhere on an interval...
Authenticity of Mathematical Modeling
Tran, Dung; Dougherty, Barbara J.
2014-01-01
Some students leave high school never quite sure of the relevancy of the mathematics they have learned. They fail to see links between school mathematics and the mathematics of everyday life that requires thoughtful decision making and often complex problem solving. Is it possible to bridge the gap between school mathematics and the mathematics in…
The effect of trauma on Neanderthal culture: A mathematical analysis.
Nakahashi, W
2017-02-04
Traumatic lesions are often observed in ancient skeletal remains. Since ancient medical technology was immature, severely traumatized individuals may have frequently lost the physical ability for cultural skills that demand complex body movements. I develop a mathematical model to analyze the effect of trauma on cultural transmission and apply it to Neanderthal culture using Neanderthal fossil data. I estimate from the data that the proportion of adult individuals who suffered traumatic injuries before death was approximately 0.79-0.94, in which 0.37-0.52 were injured severely and 0.13-0.19 were injured before adulthood. Assuming that every severely traumatized individual and a quarter to a half of the other traumatized individuals lost the capacity for a cultural skill that demands complex control of the traumatized body part, I estimate that if an upper limb is associated with a cultural skill, each individual had to communicate closely with at least 1.5-2.6 individuals during adulthood to maintain the skill in Neanderthal society, and if a whole body is associated, at least 3.1-11.5 individuals were necessary. If cultural transmissions between experts and novices were inaccurate, or if low frequency skills easily disappeared from the population due to random drift, more communicable individuals were necessary. Since the community size of Neanderthals was very small, their high risk of injury may have inhibited the spread of technically difficult cultural skills in their society. It may be important to take this inhibition into consideration when we study Neanderthal culture and the replacement of Neanderthals by modern humans.
Tang, Michael; David, Hyerle; Byrne, Roxanne; Tran, John
2012-01-01
This paper is a mathematical (Boolean) analysis a set of cognitive maps called Thinking Maps[R], based on Albert Upton's semantic principles developed in his seminal works, Design for Thinking (1961) and Creative Analysis (1961). Albert Upton can be seen as a brilliant thinker who was before his time or after his time depending on the future of…
Tang, Michael; David, Hyerle; Byrne, Roxanne; Tran, John
2012-01-01
This paper is a mathematical (Boolean) analysis a set of cognitive maps called Thinking Maps[R], based on Albert Upton's semantic principles developed in his seminal works, Design for Thinking (1961) and Creative Analysis (1961). Albert Upton can be seen as a brilliant thinker who was before his time or after his time depending on the future of…
A Meta-Analysis of the Effects of Computer Technology on School Students' Mathematics Learning
Li, Qing; Ma, Xin
2010-01-01
This study examines the impact of computer technology (CT) on mathematics education in K-12 classrooms through a systematic review of existing literature. A meta-analysis of 85 independent effect sizes extracted from 46 primary studies involving a total of 36,793 learners indicated statistically significant positive effects of CT on mathematics…
The Mathematical Analysis of Electrical and Optical Wave-Motion
Bateman, H.
2016-10-01
1. Fundamental ideas; 2. General survey of the different methods of solving the wave-equation; 3. Polar coordinates; 4. Cylindrical coordinates; 5. The problem of diffraction; 6. Transformations of coordinates appropriate for the treatment of problems connected with a surface of revolution; 7. Homogeneous solutions of the wave-equation; 8. Electromagnetic fields with moving singularities; 9. Miscellaneous theories; List of authors quoted; Index.
Mathematical Modeling and Analysis of Classified Marketing of Agricultural Products
Institute of Scientific and Technical Information of China (English)
Fengying; WANG
2014-01-01
Classified marketing of agricultural products was analyzed using the Logistic Regression Model. This method can take full advantage of information in agricultural product database,to find factors influencing best selling degree of agricultural products,and make quantitative analysis accordingly. Using this model,it is also able to predict sales of agricultural products,and provide reference for mapping out individualized sales strategy for popularizing agricultural products.
Directory of Open Access Journals (Sweden)
Tatiana Sergeevna SIRENKO
2014-01-01
Full Text Available The article is devoted to the research of the prag-matic aspect of citation in fictional text from the in-tertextual point of view. The theory of intertextuality was formed in the works of M.Bakhtin and devel-oped by Y. Kristeva after the analysis of the works of post-modern writers. So allusion and citation began to be investigated not from the philology point of view only but from the linguistics as well. The pur-pose of the article is to investigate the pragmatic aspect of citation which includes also the investiga-tion of its pragmatic functions. Different views on the citation classification are also mentioned in the article as it is an actual problem in modern linguis-tics. Novels by British writer J. Fforde are the mate-rial for the investigation article because they pos-sess a big amount of intertextual inclusion in the text in general and citation in particular.
Boyer, Carl B
1989-01-01
"Boyer and Merzbach distill thousands of years of mathematics into this fascinating chronicle. From the Greeks to Godel, the mathematics is brilliant; the cast of characters is distinguished; the ebb and flow of ideas is everywhere evident. And, while tracing the development of European mathematics, the authors do not overlook the contributions of Chinese, Indian, and Arabic civilizations. Without doubt, this is--and will long remain--a classic one-volume history of mathematics and mathematicians who create it." --William Dunham Author, Journey Through Genius, The Great Theorems of Mathematics "When we read a book like A History of Mathematics, we get the picture of a mounting structure, ever taller and broader and more beautiful and magnificent--and with a foundation, moreover, that is as untainted and as functional now as it was when Thales worked out the first geometrical theorems nearly 26 centuries ago." --From the Foreword by Isaac Asimov "One of the most useful and comprehensive general introductions t...
Lutscher, Frithjof; Lewis, Mark A
2004-03-01
This paper is concerned with mathematical analysis of the 'critical domain-size' problem for structured populations. Space is introduced explicitly into matrix models for stage-structured populations. Movement of individuals is described by means of a dispersal kernel. The mathematical analysis investigates conditions for existence, stability and uniqueness of equilibrium solutions as well as some bifurcation behaviors. These mathematical results are linked to species persistence or extinction in connected habitats of different sizes or fragmented habitats; hence the framework is given for application of such models to ecology. Several approximations which reduce the complexity of integrodifference equations are given. A simple example is worked out to illustrate the analytical results and to compare the behavior of the integrodifference model to that of the approximations.
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)
Reid, Anna; Wood, Leigh N.; Smith, Geoff H.; Petocz, Peter
2005-01-01
In this paper, we describe and investigate three aspects of learning mathematics: intention, approach and outcome. These aspects have emerged from interviews with students where their experience of learning mathematics, their understanding of mathematics as a discipline field, and their perception of work as a mathematician were the objects of…
Weighted analysis of general microarray experiments
Directory of Open Access Journals (Sweden)
Kristiansson Erik
2007-10-01
Full Text Available Abstract Background In DNA microarray experiments, measurements from different biological samples are often assumed to be independent and to have identical variance. For many datasets these assumptions have been shown to be invalid and typically lead to too optimistic p-values. A method called WAME has been proposed where a variance is estimated for each sample and a covariance is estimated for each pair of samples. The current version of WAME is, however, limited to experiments with paired design, e.g. two-channel microarrays. Results The WAME procedure is extended to general microarray experiments, making it capable of handling both one- and two-channel datasets. Two public one-channel datasets are analysed and WAME detects both unequal variances and correlations. WAME is compared to other common methods: fold-change ranking, ordinary linear model with t-tests, LIMMA and weighted LIMMA. The p-value distributions are shown to differ greatly between the examined methods. In a resampling-based simulation study, the p-values generated by WAME are found to be substantially more correct than the alternatives when a relatively small proportion of the genes is regulated. WAME is also shown to have higher power than the other methods. WAME is available as an R-package. Conclusion The WAME procedure is generalized and the limitation to paired-design microarray datasets is removed. The examined other methods produce invalid p-values in many cases, while WAME is shown to produce essentially valid p-values when a relatively small proportion of genes is regulated. WAME is also shown to have higher power than the examined alternative methods.
Limits, limits everywhere the tools of mathematical analysis
Applebaum, David
2012-01-01
A quantity can be made smaller and smaller without it ever vanishing. This fact has profound consequences for science, technology, and even the way we think about numbers. In this book, we will explore this idea by moving at an easy pace through an account of elementary real analysis and, in particular, will focus on numbers, sequences, and series.Almost all textbooks on introductory analysis assume some background in calculus. This book doesn't and, instead, the emphasis is on the application of analysis to number theory. The book is split into two parts. Part 1 follows a standard university
Comparative analysis of mathematical models of the matrix photodetector used in digital holography
Grebenyuk, K. A.
2017-08-01
It is established, that in modern works on digital holography, three fundamentally different mathematical models of a matrix photodetector are used. Comparative analysis of these models, including analysis of the formula of each model and test calculations, has been conducted. The possibility of using these models to account for the influence of geometrical parameters of a matrix photodetector on the properties of recorded digital holograms is considered.
Stability Analysis of a Mathematical Model for Onchocerciaisis ...
African Journals Online (AJOL)
ADOWIE PERE
transmission dynamics and control of Onchocerciasis was developed ... varying population size (birth rate not equal to death removal rate), and standard ... ordinary differential equations. ..... Diseases: Model building, analysis and. Integration.
Mathematical and physical theory of turbulence
Cannon, John
2006-01-01
Although the current dynamical system approach offers several important insights into the turbulence problem, issues still remain that present challenges to conventional methodologies and concepts. These challenges call for the advancement and application of new physical concepts, mathematical modeling, and analysis techniques. Bringing together experts from physics, applied mathematics, and engineering, Mathematical and Physical Theory of Turbulence discusses recent progress and some of the major unresolved issues in two- and three-dimensional turbulence as well as scalar compressible turbulence. Containing introductory overviews as well as more specialized sections, this book examines a variety of turbulence-related topics. The authors concentrate on theory, experiments, computational, and mathematical aspects of Navier-Stokes turbulence; geophysical flows; modeling; laboratory experiments; and compressible/magnetohydrodynamic effects. The topics discussed in these areas include finite-time singularities a...
Dependence of the firearm-related homicide rate on gun availability: a mathematical analysis.
Wodarz, Dominik; Komarova, Natalia L
2013-01-01
In the USA, the relationship between the legal availability of guns and the firearm-related homicide rate has been debated. It has been argued that unrestricted gun availability promotes the occurrence of firearm-induced homicides. It has also been pointed out that gun possession can protect potential victims when attacked. This paper provides a first mathematical analysis of this tradeoff, with the goal to steer the debate towards arguing about assumptions, statistics, and scientific methods. The model is based on a set of clearly defined assumptions, which are supported by available statistical data, and is formulated axiomatically such that results do not depend on arbitrary mathematical expressions. According to this framework, two alternative scenarios can minimize the gun-related homicide rate: a ban of private firearms possession, or a policy allowing the general population to carry guns. Importantly, the model identifies the crucial parameters that determine which policy minimizes the death rate, and thus serves as a guide for the design of future epidemiological studies. The parameters that need to be measured include the fraction of offenders that illegally possess a gun, the degree of protection provided by gun ownership, and the fraction of the population who take up their right to own a gun and carry it when attacked. Limited data available in the literature were used to demonstrate how the model can be parameterized, and this preliminary analysis suggests that a ban of private firearm possession, or possibly a partial reduction in gun availability, might lower the rate of firearm-induced homicides. This, however, should not be seen as a policy recommendation, due to the limited data available to inform and parameterize the model. However, the model clearly defines what needs to be measured, and provides a basis for a scientific discussion about assumptions and data.
Dependence of the firearm-related homicide rate on gun availability: a mathematical analysis.
Directory of Open Access Journals (Sweden)
Dominik Wodarz
Full Text Available In the USA, the relationship between the legal availability of guns and the firearm-related homicide rate has been debated. It has been argued that unrestricted gun availability promotes the occurrence of firearm-induced homicides. It has also been pointed out that gun possession can protect potential victims when attacked. This paper provides a first mathematical analysis of this tradeoff, with the goal to steer the debate towards arguing about assumptions, statistics, and scientific methods. The model is based on a set of clearly defined assumptions, which are supported by available statistical data, and is formulated axiomatically such that results do not depend on arbitrary mathematical expressions. According to this framework, two alternative scenarios can minimize the gun-related homicide rate: a ban of private firearms possession, or a policy allowing the general population to carry guns. Importantly, the model identifies the crucial parameters that determine which policy minimizes the death rate, and thus serves as a guide for the design of future epidemiological studies. The parameters that need to be measured include the fraction of offenders that illegally possess a gun, the degree of protection provided by gun ownership, and the fraction of the population who take up their right to own a gun and carry it when attacked. Limited data available in the literature were used to demonstrate how the model can be parameterized, and this preliminary analysis suggests that a ban of private firearm possession, or possibly a partial reduction in gun availability, might lower the rate of firearm-induced homicides. This, however, should not be seen as a policy recommendation, due to the limited data available to inform and parameterize the model. However, the model clearly defines what needs to be measured, and provides a basis for a scientific discussion about assumptions and data.
The Unit of Analysis in Mathematics Education: Bridging the Political-Technical Divide?
Ernest, Paul
2016-01-01
Mathematics education is a complex, multi-disciplinary field of study which treats a wide range of diverse but interrelated areas. These include the nature of mathematics, the learning of mathematics, its teaching, and the social context surrounding both the discipline and applications of mathematics itself, as well as its teaching and learning.…
Kharuddin, Azrul Fazwan; Ismail, Noor Azina
2017-01-01
Integrating technology in the mathematics curriculum has become a necessary task for curriculum developers as well as mathematics practitioners across the world and time. In general research studies seeking a better understanding of how best to integrate mathematics analysis tools with mathematics subject matter normally observe mathematics…
Directory of Open Access Journals (Sweden)
Vitor Geraldi Haase
2012-01-01
Full Text Available Mathematics anxiety has been associated to performance in school mathematics. The association between math anxiety and psychosocial competencies as well as their specific contribution to explain school mathematics performance are still unclear. In the present study, the impact of sociodemographic factors, psychosocial competencies, and math anxiety on mathematics and spelling performance was examined in school children with and without mathematics difficulties. The specific contributions of psychosocial competencies (i.e., general anxiety and attentional deficits with hyperactivity and math anxiety (i.e., self-assessment in mathematics to school mathematics performance were found to be statistically independent from each other. Moreover, psychosocial competencies—but not math anxiety—were related also to spelling performance. These results suggest that psychosocial competencies are more related to general mechanisms of emotional regulation and emotional response towards academic performance, while mathematics anxiety is related to the specific cognitive aspect of self-assessment in mathematics.
An Analysis of Female Language Feature in Desperate Housewives from Stylistic Aspect
Institute of Scientific and Technical Information of China (English)
乌日乐; 乔烨辛
2014-01-01
Desperate Housewives is an American teleplay which was broadcast by American Broadcasting Company in 2004. It de-scribes the married life and some humorous stories about housewives who live on Wisteria Lane. In this teleplay, the talk has its unique features during the housewives, so it is worthy of studying. The thesis takes the Desperate Housewives as an object of study and from stylistic aspect to analysis and study the female language. Though the analysis, the conclusion is following:females tend to use intensifiers words, in vocabulary aspects;and in syntactical aspects, females like to use hedges, tag questions. And in gram-mar aspect, elliptical sentences and inverted sentences are quite popular among females.
Analysis of hotel enterprises competitiveness aspects in modern business
Directory of Open Access Journals (Sweden)
Bogetić Srđan
2015-01-01
Full Text Available In terms of global competition, which is characterized by constant improvement of existing and the emergence of new tourist destination, tourism is nowdays one of the initiators in development of the national economy. It is important to point out that the relation of tourists toward travelling changed with greater differentiation and the emergence of new market niches. The reason for this relationship lies in the fact that tourists, due to the greater application of information and communication technologies (ICT, have become very well informed about the tourist destinations they visit, their cultural and other facilities, as well as hotels and the services they offer. In order to meet the demands of their customers, hotel companies have to follow market trends and implement new management concepts into their business practices. Hotel companies today take into account not only their customers, but also the society in which they operate. The issue of sustainable development has become the sphere of interest for hotel companies, and they are paying a lot of attention to the following areas: environmental protection, waste management, application of clean technologies and the alike. The ICT applications have a significant role in hotel industries operations since they accelerate communication with customers and also reduce operating costs through the use of different software solutions for accommodation bookings. Nowdays, customers demand quick information and the use of the internet in hotels allows this service.
Attitudes of university precalculus students toward mathematics.
Alkhateeb, Haitham M; Mji, Andile
2005-04-01
To investigate the attitudes of 200 university students (83% freshmen) toward mathematics, a questionnaire was administered to report on their attitudes toward mathematics. Analysis indicated that students studying precalculus had a somewhat positive attitude toward mathematics.
Aspects of seat modelling for seating comfort analysis
Verver, M.M.; Lange, R. de; Hoof, J.F.A.M. van; Wismans, J.S.H.M.
2005-01-01
The development of more comfortable seats is an important issue in the automotive industry. However, the development of new car seats is very time consuming and costly since it is typically based on experimental evaluation using prototypes. Computer models of the human-seat interaction could
Aspects of seat modelling for seating comfort analysis
Verver, M.M.; Lange, R. de; Hoof, J.F.A.M. van; Wismans, J.S.H.M.
2005-01-01
The development of more comfortable seats is an important issue in the automotive industry. However, the development of new car seats is very time consuming and costly since it is typically based on experimental evaluation using prototypes. Computer models of the human-seat interaction could acceler
Hornburg, Caroline Byrd; Rieber, Marisa L; McNeil, Nicole M
2017-11-01
This study examined gender as a potential source of variation in children's formal understanding of mathematical equivalence. The hypothesis was that girls would perform more poorly than boys. An integrative data analysis was conducted with 960 second and third graders across 14 previously conducted studies of children's understanding of mathematical equivalence. Measures included problem solving, problem encoding, and equal sign definition. Overall, children performed poorly on all measures. As predicted, girls were less likely than boys to solve mathematical equivalence problems correctly, even though there were no gender differences in calculation accuracy. In addition, girls were more likely than boys to use the "add-all" strategy, an incorrect strategy that has been shown to be more resistant to change than other incorrect strategies. There were not statistically significant differences for encoding or defining the equal sign, suggesting that deficits may reflect girls' tendency to follow taught algorithms. Copyright © 2017 Elsevier Inc. All rights reserved.
A mathematical formulation for large strain analysis of geologic continua
Energy Technology Data Exchange (ETDEWEB)
Chaudhary, A.B.; Vakili, J.E.; Hume, H.R.
1987-12-01
A solution method is presented for finite-deformation analysis of geologic materials. The principle of virtual work is used to state the equations of equilibrium in a weak form. These equations are linearized about the last-established equilibrium configuration. A material constitutive relationship between the Green-Naghdi stress rate and the rate-of-deformation tensor is used to obtain the current stresses. The finite-element governing equations are expressed in a form suitable for an iterative solution strategy. The obtained gradient matrix contains the effects of both material and geometric nonlinearities. The primary application area of this formulation is the analysis of long-term deformation response of the region adjoining the mining shafts and the waste emplacement rooms within a nuclear waste repository. In this region, the strains are expected to be large, and the infinitesimal strain analysis would introduce inaccuracies in the solution. 19 refs., 6 figs.
METHODICAL AND PRACTICAL ASPECTS OF PRODUCTION RESOURCES’ ANALYSIS ON ENTERPRISE
Directory of Open Access Journals (Sweden)
Svitlana V. Andros
2008-10-01
Full Text Available The specific features of resources cost estimation methods which are characterized by firmness and lightness of error correction and untypical operations processing are explored. A primary purpose is enterprises production resources record-keeping method perfection to provide their effective forms of economic activity and operations management. The planned capitalization influencing decline calculations on expenses in production are carried out. Balance estimations of production resources are examined, those coincides with estimations liquidating types and in ordinary terms correspond to the material unit minimum cost. The research consists of founding to use expedience of resources cost estimation methods characterized by firmness and lightness of error correction and untypical operations treatment in the enterprise registration policy also.
Safety Aspect Analysis of Helmet Mounted Millimeter Wave Radio
Directory of Open Access Journals (Sweden)
K. Nageswari
1999-07-01
Full Text Available Measurements of millimetric wave (MMW power density from two-helmet-mounted MMW radiating horn antennas were made at various distances on the three axes. These three axes are representing three planes: (i in the direction of propagation (Z-axis, (ii horizontal axis perpendicular to the direction of propagation (Y-axis, i.e., 15 cm to the left or right of Z-axis, and (iii vertical axis (X-axis also perpendicular to the direction of propagation and extending up and down an imaginary central reference line passing through the centre of the horn and the centre of the microwave measuring probe. Measurements were also made inside the helmet close to the metallic plate at 17 locations and 10 cm away from it. The Narda-8723 broadband isotropic microwave probe [frequency of operation (0.3-40 GHz power density range 0.05-100 mW/cm1 was placed at various distance points marked at 15 nm intervals and also at distances of relevance on Z-axis. For each of the distance points on Z-axis, measurements were taken at 7 probe locations on X-axis. For Y-axis measurements, 4 probe locations were selected (on vertical or X-axis. The results revealed no leakage of microwave power inside the helmets. In the transmitting mode of operation, there was a great variability of microwave power emitted closest to the horn antennas (2.5-5.0 mW / 2 and 6.0-105 mW /cm2 for helmet Nos.11 and2, respectively. As the distance from the antenna increased in the direction of propagation, the power density dropped to 0.04 m W / cm2 or 0.075 m W / cm{ maximum value at 1 m. As the values recorded are within American National Standards Institute (ANSI safety guidelines (10mW/cm2 at 35 GHz.
Computational aspects of sensitivity calculations in linear transient structural analysis
Greene, W. H.; Haftka, R. T.
1991-01-01
The calculation of sensitivities of displacements, velocities, accelerations, and stresses in linear, structural, and transient response problems is studied. Several existing sensitivity calculation methods and two new methods are compared for three example problems. Approximation vectors such as vibration mode shapes are used to reduce the dimensionality of the finite model. To be computationally practical in large-order problems, the overall finite difference methods must use the approximation vectors from the original design in the analyses of the perturbed models. This was found to result in poor convergence of stress sensitivities in several cases. Two semianalytical techniques are developed to overcome this poor convergence. Both new methods result in very good convergence of the stress sensitivities; the computational cost is much less than would result if the vibration modes were recalculated and then used in an overall finite difference method.
Aspects of seat modelling for seating comfort analysis.
Verver, M M; de Lange, R; van Hoof, J; Wismans, J S H M
2005-01-01
The development of more comfortable seats is an important issue in the automotive industry. However, the development of new car seats is very time consuming and costly since it is typically based on experimental evaluation using prototypes. Computer models of the human-seat interaction could accelerate this process. The objective of this paper is to establish a protocol for the development of seat models using numerically efficient simulation techniques. The methodology is based on multi-body techniques: arbitrary surfaces, providing an accurate surface description, are attached to rigid bodies. The bodies are connected by kinematic joints, representing the seat back recliner and head restraint joint. Properties of the seat foam and frame have been lumped together. Further, experiments have been defined to characterise the mechanical properties required for the seat model for comfort applications. The protocol has been exemplified using a standard car seat. The seat model has been validated based on experiments with rigid loading devices with human-like shapes in terms of force-deflection characteristics. The response of the seat model agrees well with the experimental results. Therefore the presented method can be a useful tool in the seat development process, especially in early stages of the design process.
Analysis of common mode inductors and optimization aspects
Roc'h, A.; Leferink, Frank Bernardus Johannes; Zare, Firuz
2011-01-01
The common mode inductors, or common mode chokes, are a key component of electromagnetic interference filters. Engineers usually face significant design challenges such as size, cost and weight while working with these components. To avoid the construction of several prototypes, often oversized, eng
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.
Directory of Open Access Journals (Sweden)
Ziya Serhan
2010-06-01
Full Text Available Abstract Objectives A recent joint report from the Institute of Medicine and the National Academy of Engineering, highlights the benefits of--indeed, the need for--mathematical analysis of healthcare delivery. Tools for such analysis have been developed over decades by researchers in Operations Research (OR. An OR perspective typically frames a complex problem in terms of its essential mathematical structure. This article illustrates the use and value of the tools of operations research in healthcare. It reviews one OR tool, queueing theory, and provides an illustration involving a hypothetical drug treatment facility. Method Queueing Theory (QT is the study of waiting lines. The theory is useful in that it provides solutions to problems of waiting and its relationship to key characteristics of healthcare systems. More generally, it illustrates the strengths of modeling in healthcare and service delivery. Queueing theory offers insights that initially may be hidden. For example, a queueing model allows one to incorporate randomness, which is inherent in the actual system, into the mathematical analysis. As a result of this randomness, these systems often perform much worse than one might have guessed based on deterministic conditions. Poor performance is reflected in longer lines, longer waits, and lower levels of server utilization. As an illustration, we specify a queueing model of a representative drug treatment facility. The analysis of this model provides mathematical expressions for some of the key performance measures, such as average waiting time for admission. Results We calculate average occupancy in the facility and its relationship to system characteristics. For example, when the facility has 28 beds, the average wait for admission is 4 days. We also explore the relationship between arrival rate at the facility, the capacity of the facility, and waiting times. Conclusions One key aspect of the healthcare system is its complexity, and
2010-01-01
Objectives A recent joint report from the Institute of Medicine and the National Academy of Engineering, highlights the benefits of--indeed, the need for--mathematical analysis of healthcare delivery. Tools for such analysis have been developed over decades by researchers in Operations Research (OR). An OR perspective typically frames a complex problem in terms of its essential mathematical structure. This article illustrates the use and value of the tools of operations research in healthcare. It reviews one OR tool, queueing theory, and provides an illustration involving a hypothetical drug treatment facility. Method Queueing Theory (QT) is the study of waiting lines. The theory is useful in that it provides solutions to problems of waiting and its relationship to key characteristics of healthcare systems. More generally, it illustrates the strengths of modeling in healthcare and service delivery. Queueing theory offers insights that initially may be hidden. For example, a queueing model allows one to incorporate randomness, which is inherent in the actual system, into the mathematical analysis. As a result of this randomness, these systems often perform much worse than one might have guessed based on deterministic conditions. Poor performance is reflected in longer lines, longer waits, and lower levels of server utilization. As an illustration, we specify a queueing model of a representative drug treatment facility. The analysis of this model provides mathematical expressions for some of the key performance measures, such as average waiting time for admission. Results We calculate average occupancy in the facility and its relationship to system characteristics. For example, when the facility has 28 beds, the average wait for admission is 4 days. We also explore the relationship between arrival rate at the facility, the capacity of the facility, and waiting times. Conclusions One key aspect of the healthcare system is its complexity, and policy makers want to
Introducing philosophy of mathematics
Friend, Michele
2014-01-01
What is mathematics about? Does the subject-matter of mathematics exist independently of the mind or are they mental constructions? How do we know mathematics? Is mathematical knowledge logical knowledge? And how is mathematics applied to the material world? In this introduction to the philosophy of mathematics, Michele Friend examines these and other ontological and epistemological problems raised by the content and practice of mathematics. Aimed at a readership with limited proficiency in mathematics but with some experience of formal logic it seeks to strike a balance between conceptual acc
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.
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.
Technology in Mathematics Classrooms: A Meta-Analysis of the Recent Literature
Li, Qing; Ma, Xin
2008-01-01
The increasingly use of technology in education does set off a flurry of research studies that focus on the successfulness and effectiveness of technology in elementary and secondary education. In this study, we conducted a comprehensive meta-analysis of research literature on technology in relation to mathematics teaching and learning.…
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
An epistemic framing analysis of upper level physics students' use of mathematics
Bing, Thomas Joseph
Mathematics is central to a professional physicist's work and, by extension, to a physics student's studies. It provides a language for abstraction, definition, computation, and connection to physical reality. This power of mathematics in physics is also the source of many of the difficulties it presents students. Simply put, many different activities could all be described as "using math in physics". Expertise entails a complicated coordination of these various activities. This work examines the many different kinds of thinking that are all facets of the use of mathematics in physics. It uses an epistemological lens, one that looks at the type of explanation a student presently sees as appropriate, to analyze the mathematical thinking of upper level physics undergraduates. Sometimes a student will turn to a detailed calculation to produce or justify an answer. Other times a physical argument is explicitly connected to the mathematics at hand. Still other times quoting a definition is seen as sufficient, and so on. Local coherencies evolve in students' thought around these various types of mathematical justifications. We use the cognitive process of framing to model students' navigation of these various facets of math use in physics. We first demonstrate several common framings observed in our students' mathematical thought and give several examples of each. Armed with this analysis tool, we then give several examples of how this framing analysis can be used to address a research question. We consider what effects, if any, a powerful symbolic calculator has on students' thinking. We also consider how to characterize growing expertise among physics students. Framing offers a lens for analysis that is a natural fit for these sample research questions. To active physics education researchers, the framing analysis presented in this dissertation can provide a useful tool for addressing other research questions. To physics teachers, we present this analysis so that it
Mathematical modelling and linear stability analysis of laser fusion cutting
Hermanns, Torsten; Schulz, Wolfgang; Vossen, Georg; Thombansen, Ulrich
2016-06-01
A model for laser fusion cutting is presented and investigated by linear stability analysis in order to study the tendency for dynamic behavior and subsequent ripple formation. The result is a so called stability function that describes the correlation of the setting values of the process and the process' amount of dynamic behavior.
Towards the mathematics of quantum field theory
Paugam, Frédéric
2014-01-01
The aim of this book is to introduce mathematicians (and, in particular, graduate students) to the mathematical methods of theoretical and experimental quantum field theory, with an emphasis on coordinate-free presentations of the mathematical objects in play. This should in turn promote interaction between mathematicians and physicists by supplying a common and flexible language for the good of both communities, even if the mathematical one is the primary target. This reference work provides a coherent and complete mathematical toolbox for classical and quantum field theory, based on categorical and homotopical methods, representing an original contribution to the literature. The first part of the book introduces the mathematical methods needed to work with the physicists' spaces of fields, including parameterized and functional differential geometry, functorial analysis, and the homotopical geometric theory of non-linear partial differential equations, with applications to general gauge theories. The second...
Directory of Open Access Journals (Sweden)
Ali İhsan BORAN
2015-04-01
Full Text Available The purpose of this study is to investigate relationship of mathematics Olympiad (analysis-algebra and geometry scores of gifted students with IQ scores (verbal, performance and general and mathematics achievement scores of the gifted students. Study group of the study included 64 gifted students (27 girls and 37 boys who took courses from one Science and Art Center. Data of study involved scores of the participants on mathematics Olympiad exam, WISC-R test and school mathematics achievement. For analysis of the data Pearson correlation analysis, Spearman correlation analysis, independent groups’ t-test and Mann Whitney U test were utilized. The findings showed that there was no significant relationship between the Olympiad scores on analysis-algebra and geometry and IQ scores (general, performance and verbal. But the Olympiad scores on analysis-algebra and geometry factors were significantly related to school mathematics achievement. Comparing IQ scores of highest and lowest scorer groups on the Olympiad scores showed that there were no significant differences between IQ scores (general, performance and verbal of the groups. However school mathematics scores of the participants significantly differed in terms of groups determined based on analysis-algebra and geometry scores.
Brantlinger, Andrew
2011-01-01
This paper presents findings from a comparative analysis of three similar secondary geometry texts, one critical unit, one standards-based reform unit, and one specialist chapter. I developed the critical unit as I took the tenets of critical mathematics (CM) and substantiated them in printed curricular materials in which to teach as part of a…
Energy Technology Data Exchange (ETDEWEB)
Gradoboyev, S.A.; Chudnovskiy, G.L.; Churikov, L.I.; Kolpakov, N.F.; Krasnov, B.S.; Mikhalev, M.K.; Yefremov, Y.P.
1981-01-01
Experience is analyzed of economic-mathematical modeling of the development of extracting sectors of industry from the viewpoint of the regional sector complex. Characteristics and features are examined of isolating and including into the system of models a group of related sectors. Procedures are developed for constructing a multiple-level model which reflects the basic laws governing the functioning and interaction of production subsystems. A new variant is proposed for mathematical description of the process of geological extraction under complicated conditions of regions of new development.
Attitude Determination Error Analysis System (ADEAS) mathematical specifications document
Nicholson, Mark; Markley, F.; Seidewitz, E.
1988-01-01
The mathematical specifications of Release 4.0 of the Attitude Determination Error Analysis System (ADEAS), which provides a general-purpose linear error analysis capability for various spacecraft attitude geometries and determination processes, are presented. The analytical basis of the system is presented. The analytical basis of the system is presented, and detailed equations are provided for both three-axis-stabilized and spin-stabilized attitude sensor models.
Mathematical analysis and uncertain models of a nitrification process
Energy Technology Data Exchange (ETDEWEB)
Harmand, J.; Steyer, J.P.; Queinnec, I.; Bernet, N.
1995-12-31
The non linear model of a Continuous Strirred Tank Reactor (CSTR) for nitrogen removal, derived from mass balance consideration, can be linearized around a nominal steady state. The analysis of the linear model in terms of stability, observability and controllability allows to highlight the structural properties of the model. Disturbances and uncertainties can then be explicitly expressed in the linear model, such that it completes the modelling in view of a future control scheme of the process. (authors) 13 refs.
Athappilly, Kuriakose; And Others
1983-01-01
The aggregate findings of experiments with modern mathematics for the last 30 years show that there have not been many detrimental effects of "new math" either on achievement or attitude. Instead, the evidence points toward beneficial effects in terms of improvement in overall achievement and attitude. (Author/BW)
Gisladottir, Berglind
2013-01-01
This study examines the impact of social capital on mathematics achievement in eight European cities. The study draws on data from the 2008 Youth in Europe survey, carried out by the Icelandic Center for Social Research and Analysis. The sample contains responses from 17,312 students in 9th and 10th grade of local secondary schools in the…
Mathematical Description of Wafer-1, a Three-Dimensional Code for LWR Fuel Performance Analysis
DEFF Research Database (Denmark)
Kjær-Pedersen, Niels
1975-01-01
This article describes in detail the mathematical formulation used in the WAFER-1 code, which is presently used for three-dimensional analysis of LWR fuel pin performance. The code aims at a prediction of the local stress-strain history in the cladding, especially with regard to the ridging pheno...
Some aspects of design and analysis of selection programmes in aquaculture species.
Li, Y; Ponzoni, R W
2015-04-01
The aquaculture industry is one of the fastest growing animal food-producing sectors in the world, largely driven by an increasing demand for high-quality protein from developing countries. However, the majority of cultured production of aquatic species currently relies heavily on the collection of wild animals for use as broodstock. Aquatic animal domestication and genetic selection programmes in controlled environments are essential to enable the provision of a continued supply of high-quality food for an ever-expanding world population. Professor John James' significant contributions to the genetic improvement of conventional livestock species are well known. By contrast, his contributions to the aquaculture industry are less well known, especially in the areas of design and conduct of selective breeding programmes in aquatic animal species. In this study, we focus on a few aspects of aquaculture genetics to which Professor James made substantial contributions. His outstanding ability to comprehend, clarify and simplify complex problems with easy-to-understand mathematical derivations is clearly demonstrated in the areas of large-scale strain comparisons, genotype-by-environment interactions (GxE), transformations and interpretation of selection response, as well as in the treatment of economic aspects of designing breeding programmes.
Mathematical foundations of elasticity
Marsden, Jerrold E
1994-01-01
This advanced-level study approaches mathematical foundations of three-dimensional elasticity using modern differential geometry and functional analysis. It is directed to mathematicians, engineers and physicists who wish to see this classical subject in a modern setting with examples of newer mathematical contributions. Prerequisites include a solid background in advanced calculus and the basics of geometry and functional analysis.The first two chapters cover the background geometry ― developed as needed ― and use this discussion to obtain the basic results on kinematics and dynamics of con
Directory of Open Access Journals (Sweden)
Nęcka Edward
2016-04-01
Full Text Available Starting from the assumption that working memory capacity is an important predictor of general fluid intelligence, we asked which aspects of working memory account for this relationship. Two theoretical stances are discussed. The first one posits that the important explanatory factor is storage capacity, roughly defined as the number of chunks possible to hold in the focus of attention. The second one claims that intelligence is explained by the efficiency of executive control, for instance, by prepotent response inhibition. We investigated 96 children at the age between 10 and 13. They completed a version of the n-back task that allows assessment of both storage capacity and inhibitory control. They also completed Raven’s Progressive Matrices as the fluid intelligence test and the Test for Creative Thinking - Drawing Production, for control purposes. We found that Raven’s scores correlated negatively with the number of unnecessary responses to irrelevant stimuli but they did not correlate with the number of signal detections. We conclude that children’s fluid intelligence depends on inhibitory control, with no relationship with storage capacity.
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.
Sewry, Joyce; Mokilane, Paul
2014-01-01
The National Senior Certificate (NSC) examinations were written for the second time in 2009 amid much criticism. In this study, scripts of candidates who wrote the NSC Mathematics examinations (papers 1 and 2) in 2009 were used as data to analyse the marks scored and then polytomous Rasch analysis was conducted for all the sub-questions to…
Wosnitza, Marold; Volet, Simone
2014-01-01
This paper examines how distinct trajectories of change in students' general views of group work over the duration of one single group assignment could be explained by multidimensional aspects of their experience and the overall instructional context. Science (336) and Education (377) students involved in a semester-long group assignment…
Mathematical model for analysis of recirculating vertical flow constructed wetlands.
Sklarz, Menachem Y; Gross, Amit; Soares, M Ines M; Yakirevich, Alexander
2010-03-01
The recirculating vertical flow constructed wetland (RVFCW) was developed for the treatment of domestic wastewater (DWW). In this system, DWW is applied to a vertical flow bed through which it trickles into a reservoir located beneath the bed. It is then recirculated back to the root zone of the bed. In this study, a compartmental model was developed to simulate the RVFCW. The model, which addresses transport and removal kinetics of total suspended solids, 5-day biological oxygen demand and nitrogen, was fitted to kinetical results obtained from pilot field setups and a local sensitivity analysis was performed on the model parameters and operational conditions. This analysis showed that after 5h of treatment water quality is affected more by stochastic events than by the model parameter values, emphasizing the stability of the RVFCW system to large variations in operational conditions. Effluent quality after 1h of treatment, when the sensitivity analysis showed the parameter impacts to be largest, was compared to model predictions. The removal rate was found to be dependent on the recirculation rate. The predictions correlated well with experimental observations, leading to the conclusion that the proposed model is a satisfactory tool for studying RVFCWs. Copyright 2009 Elsevier Ltd. All rights reserved.
Figures of thought mathematics and mathematical texts
Reed, David
2003-01-01
Examines the ways in which mathematical works can be read as texts, examines their textual strategiesand demonstrates that such readings provide a rich source of philosophical debate regarding mathematics.
2007-01-01
The integration of discrete mathematics into the secondary school curriculum (grades 7-12) is an important consideration because the mathematical area is dynamic and interesting, providing students the development of mathematical thinking. Also, it provides for teachers the opportunity to develop innovative mathematics instruction. Since the publication of the document Curriculum and Evaluation Standards for School Mathematics (NCTM, 1989), it has been difficult to determine how many schools ...
COMPARATIVE ANALYSIS OF INNOVATION ASPECT EVIDENCE IN CONSTRUCTION AND MULTI-SECTOR COMPANIES
Directory of Open Access Journals (Sweden)
Ricardo Floriani
2010-12-01
Full Text Available The goal of this study is to make a comparative analysis of innovation aspect evidence among construction and multi-sector companies. Descriptive research was done through a content analysis of administration reports from 2005 to 2007. From the researched material, 14 aspects of innovations were extracted, which offer the basis to the content analysis. Two non-probability samples were developed, the first consisting of 22 multi-sector businesses, within 18 economic sectors, which comprises the companies in the comparison. Aspects of innovation found in this group of companies were compared to those stated in the reports of the administration of the 34 construction companies with open capital, which comprise the second sample. The survey results show that the evidence of innovation aspects are different in construction companies when compared to the administration reports of multi-sector business of 2005, 2006 and 2007. The construction companies state fewer innovation aspects in the administration reports than multisector companies in the analyzed period. The conclusion is that while construction companies can be considered fairly innovative, multi-sectorial companies present more innovations on average.
Airfield Rigid Pavement Structural Design—A Review of Main Aspects and Methods of Analysis
Tiago Bonucci, Pereira
2010-05-01
Airfield pavements present a number of characteristics that make their design considerably different from that of road pavements. Apart from load magnitude and it's frequency, maintenance issues and pavement strength classification reporting are aspects that must be considered in the design phase. In the present paper, these aspects are analysed in the light of traditional and new methods of airfield pavement analysis. Parametric studies are performed in order to study the effects of different factors, such as pavement structure, layer thickness, material strength, effects of temperature, load transfer across joints and traffic characteristics.
Sequestration of carbon in saline aquifers - mathematical and numerical analysis
Energy Technology Data Exchange (ETDEWEB)
Nordbotten, Jan Martin
2004-01-01
The work in this thesis focuses equally on two main topics. The set of these subjects deals with development of criteria for monotonicity of control volume methods. These methods are important and frequently used for solving the pressure equation arising in porous media flow. First we consider homogeneous parallelogram grids, and subsequently general logical Cartesian grids in heterogeneous media. This subject is concluded by the development of a new class of Multi Point Flux Approximation methods, motivated by the monotonicity results obtained. The second topic of this thesis is the development of analytical and semi- analytical solutions to the problem of leakage through abandoned wells. More specially, we look at a set of aquifers, separated by impermeable layers (aquicludes), where injection of water or CO{sub 2} takes place in some or all the aquifers. The aquifers and aquicludes are frequently penetrated by abandoned wells from oil exploration, and our problem consists of finding solutions to flow and leakage through these wells. The goal is to obtain expressions for leakage rates that may be evaluated quickly enough such that Monte Carlo realizations over statistical distributions of properties for abandoned wells can be performed. (author)
Mathematical Creativity and Mathematical Aptitude: A Cross-Lagged Panel Analysis
Tyagi, Tarun Kumar
2016-01-01
Cross-lagged panel correlation (CLPC) analysis has been used to identify causal relationships between mathematical creativity and mathematical aptitude. For this study, 480 8th standard students were selected through a random cluster technique from 9 intermediate and high schools of Varanasi, India. Mathematical creativity and mathematical…
Mathematical Creativity and Mathematical Aptitude: A Cross-Lagged Panel Analysis
Tyagi, Tarun Kumar
2016-01-01
Cross-lagged panel correlation (CLPC) analysis has been used to identify causal relationships between mathematical creativity and mathematical aptitude. For this study, 480 8th standard students were selected through a random cluster technique from 9 intermediate and high schools of Varanasi, India. Mathematical creativity and mathematical…
Ma'rufi, Budayasa, I. Ketut; Juniati, Dwi
2017-08-01
The aim of this study was to describe the analysis of mathematics teachers' learning on algebra function limit material based on teaching experience difference. The purpose of this study is to describe the analysis of mathematics teacher's learning on limit algebraic functions in terms of the differences of teaching experience. Learning analysis focused on Pedagogical Content Knowledge (PCK) of teachers in mathematics on limit algebraic functions related to the knowledge of pedagogy. PCK of teachers on limit algebraic function is a type of specialized knowledge for teachers on how to teach limit algebraic function that can be understood by students. Subjects are two high school mathematics teacher who has difference of teaching experience they are one Novice Teacher (NP) and one Experienced Teacher (ET). Data are collected through observation of learning in the class, videos of learning, and then analyzed using qualitative analysis. Teacher's knowledge of Pedagogic defined as a knowledge and understanding of teacher about planning and organizing of learning, and application of learning strategy. The research results showed that the Knowledge of Pedagogy on subject NT in mathematics learning on the material of limit function algebra showed that the subject NT tended to describe procedurally, without explaining the reasons why such steps were used, asking questions which tended to be monotonous not be guiding and digging deeper, and less varied in the use of learning strategies while subject ET gave limited guidance and opportunities to the students to find their own answers, exploit the potential of students to answer questions, provide an opportunity for students to interact and work in groups, and subject ET tended to combine conceptual and procedural explanation.
A Mathematical Analysis of Fractional Fragmentation Dynamics with Growth
Directory of Open Access Journals (Sweden)
Emile Franc Doungmo Goufo
2014-01-01
Full Text Available We make use of the theory of strongly continuous solution operators for fractional models together with the subordination principle for fractional evolution equations (Bazhlekova (2000 and Prüss (1993 to analyze and show existence results for a fractional fragmentation model with growth characterized by its growth rate r. Indeed, strange phenomena like the phenomenon of shattering (McGrady and Ziff (1987 and the sudden appearance of infinite number of particles in some systems with initial finite particles number could not be fully explained by classical models of fragmentation or aggregation. Then, there is an increasing volition to try new approaches and extend classical models to fractional ones. In the growth model, one of the major challenges in the analysis occurs when 1/r(x is integrable at x0≥0, the minimum size of a cell. We restrict our analysis to the case of integrability of r-1 at x0. This case needs more considerations on the boundary condition, which, in this paper, is the McKendrick-von Foerster renewal condition. In the process, some properties of Mittag-Leffler relaxation function Berberan-Santos (2005 are exploited to finally prove that there is a positive solution operator to the full model.