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Sample records for mathematical analysis shows

  1. Mathematical analysis II

    CERN Document Server

    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, ...

  2. Mathematical analysis fundamentals

    CERN Document Server

    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

  3. Mathematical analysis I

    CERN Document Server

    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...

  4. Foundations of mathematical analysis

    CERN Document Server

    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

  5. Real mathematical analysis

    CERN Document Server

    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...

  6. The fundamentals of mathematical analysis

    CERN Document Server

    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

  7. Mathematical analysis II

    CERN Document Server

    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...

  8. Lectures on constructive mathematical analysis

    CERN Document Server

    Kushner, B A

    1984-01-01

    The basis of this book was a special course given by the author at the Mechanics-Mathematics Faculty of Moscow University. The material presumes almost no previous knowledge and is completely understandable to a reader who is in command of a standard course of mathematical analysis. There are an extensive bibliography and indexes which will be helpful to students.

  9. Mathematical analysis I

    CERN Document Server

    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 ...

  10. Analysis of students’ mathematical reasoning

    Science.gov (United States)

    Sukirwan; Darhim; Herman, T.

    2018-01-01

    The reasoning is one of the mathematical abilities that have very complex implications. This complexity causes reasoning including abilities that are not easily attainable by students. Similarly, studies dealing with reason are quite diverse, primarily concerned with the quality of mathematical reasoning. The objective of this study was to determine the quality of mathematical reasoning based perspective Lithner. Lithner looked at how the environment affects the mathematical reasoning. In this regard, Lithner made two perspectives, namely imitative reasoning and creative reasoning. Imitative reasoning can be memorized and algorithmic reasoning. The Result study shows that although the students generally still have problems in reasoning. Students tend to be on imitative reasoning which means that students tend to use a routine procedure when dealing with reasoning. It is also shown that the traditional approach still dominates on the situation of students’ daily learning.

  11. Fundamentals of mathematical analysis

    CERN Document Server

    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

  12. Mathematical theory of sedimentation analysis

    CERN Document Server

    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

  13. 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.

  14. A course in mathematical analysis

    CERN Document Server

    Garling, D J H

    The three volumes of A Course in Mathematical Analysis provide a full and detailed account of all those elements of real and complex analysis that an undergraduate mathematics student can expect to encounter in the first two or three years of study. Containing hundreds of exercises, examples and applications, these books will become an invaluable resource for both students and instructors. Volume 1 focuses on the analysis of real-valued functions of a real variable. Volume 2 goes on to consider metric and topological spaces. This third volume develops the classical theory of functions of a complex variable. It carefully establishes the properties of the complex plane, including a proof of the Jordan curve theorem. Lebesgue measure is introduced, and is used as a model for other measure spaces, where the theory of integration is developed. The RadonÐNikodym theorem is proved, and the differentiation of measures discussed.

  15. Mathematical analysis of complex cellular activity

    CERN Document Server

    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...

  16. Ratio Analysis: Where Investments Meet Mathematics.

    Science.gov (United States)

    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)

  17. Mathematical foundations of image processing and analysis

    CERN Document Server

    Pinoli, Jean-Charles

    2014-01-01

    Mathematical Imaging is currently a rapidly growing field in applied mathematics, with an increasing need for theoretical mathematics. This book, the second of two volumes, emphasizes the role of mathematics as a rigorous basis for imaging sciences. It provides a comprehensive and convenient overview of the key mathematical concepts, notions, tools and frameworks involved in the various fields of gray-tone and binary image processing and analysis, by proposing a large, but coherent, set of symbols and notations, a complete list of subjects and a detailed bibliography. It establishes a bridg

  18. An Ecological Analysis of Mathematics Teachers' Noticing

    Science.gov (United States)

    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…

  19. Topics in mathematical analysis and applications

    CERN Document Server

    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.

  20. Mathematical analysis, approximation theory and their applications

    CERN Document Server

    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.

  1. Showing You're Working: A Project Using Former Pupils' Experiences to Engage Current Mathematics Students

    Science.gov (United States)

    Musto, Garrod

    2008-01-01

    To help students view mathematics in a more favourable light, a number of former pupils were contacted and asked to give details of how they use mathematics in their daily lives. This information was gathered through an online questionnaire or visits to the school to talk to pupils--a booklet of responses was also given to students. Attitudinally…

  2. Mathematical Analysis of Evolution, Information, and Complexity

    CERN Document Server

    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.

  3. Mathematics

    CERN Document Server

    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

  4. Countries with Higher Levels of Gender Equality Show Larger National Sex Differences in Mathematics Anxiety and Relatively Lower Parental Mathematics Valuation for Girls.

    Science.gov (United States)

    Stoet, Gijsbert; Bailey, Drew H; Moore, Alex M; Geary, David C

    2016-01-01

    Despite international advancements in gender equality across a variety of societal domains, the underrepresentation of girls and women in Science, Technology, Engineering, and Mathematics (STEM) related fields persists. In this study, we explored the possibility that the sex difference in mathematics anxiety contributes to this disparity. More specifically, we tested a number of predictions from the prominent gender stratification model, which is the leading psychological theory of cross-national patterns of sex differences in mathematics anxiety and performance. To this end, we analyzed data from 761,655 15-year old students across 68 nations who participated in the Programme for International Student Assessment (PISA). Most importantly and contra predictions, we showed that economically developed and more gender equal countries have a lower overall level of mathematics anxiety, and yet a larger national sex difference in mathematics anxiety relative to less developed countries. Further, although relatively more mothers work in STEM fields in more developed countries, these parents valued, on average, mathematical competence more in their sons than their daughters. The proportion of mothers working in STEM was unrelated to sex differences in mathematics anxiety or performance. We propose that the gender stratification model fails to account for these national patterns and that an alternative model is needed. In the discussion, we suggest how an interaction between socio-cultural values and sex-specific psychological traits can better explain these patterns. We also discuss implications for policies aiming to increase girls' STEM participation.

  5. Countries with Higher Levels of Gender Equality Show Larger National Sex Differences in Mathematics Anxiety and Relatively Lower Parental Mathematics Valuation for Girls

    Science.gov (United States)

    2016-01-01

    Despite international advancements in gender equality across a variety of societal domains, the underrepresentation of girls and women in Science, Technology, Engineering, and Mathematics (STEM) related fields persists. In this study, we explored the possibility that the sex difference in mathematics anxiety contributes to this disparity. More specifically, we tested a number of predictions from the prominent gender stratification model, which is the leading psychological theory of cross-national patterns of sex differences in mathematics anxiety and performance. To this end, we analyzed data from 761,655 15-year old students across 68 nations who participated in the Programme for International Student Assessment (PISA). Most importantly and contra predictions, we showed that economically developed and more gender equal countries have a lower overall level of mathematics anxiety, and yet a larger national sex difference in mathematics anxiety relative to less developed countries. Further, although relatively more mothers work in STEM fields in more developed countries, these parents valued, on average, mathematical competence more in their sons than their daughters. The proportion of mothers working in STEM was unrelated to sex differences in mathematics anxiety or performance. We propose that the gender stratification model fails to account for these national patterns and that an alternative model is needed. In the discussion, we suggest how an interaction between socio-cultural values and sex-specific psychological traits can better explain these patterns. We also discuss implications for policies aiming to increase girls’ STEM participation. PMID:27100631

  6. Error Analysis in Mathematics. Technical Report #1012

    Science.gov (United States)

    Lai, Cheng-Fei

    2012-01-01

    Error analysis is a method commonly used to identify the cause of student errors when they make consistent mistakes. It is a process of reviewing a student's work and then looking for patterns of misunderstanding. Errors in mathematics can be factual, procedural, or conceptual, and may occur for a number of reasons. Reasons why students make…

  7. Problems in mathematical analysis III integration

    CERN Document Server

    Kaczor, W J

    2003-01-01

    We learn by doing. We learn mathematics by doing problems. This is the third volume of Problems in Mathematical Analysis. The topic here is integration for real functions of one real variable. The first chapter is devoted to the Riemann and the Riemann-Stieltjes integrals. Chapter 2 deals with Lebesgue measure and integration. The authors include some famous, and some not so famous, integral inequalities related to Riemann integration. Many of the problems for Lebesgue integration concern convergence theorems and the interchange of limits and integrals. The book closes with a section on Fourier series, with a concentration on Fourier coefficients of functions from particular classes and on basic theorems for convergence of Fourier series. The book is primarily geared toward students in analysis, as a study aid, for problem-solving seminars, or for tutorials. It is also an excellent resource for instructors who wish to incorporate problems into their lectures. Solutions for the problems are provided in the boo...

  8. Mathematical Creativity and Mathematical Aptitude: A Cross-Lagged Panel Analysis

    Science.gov (United States)

    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…

  9. Assessing Mathematical Competencies: An Analysis of Swedish National Mathematics Tests

    Science.gov (United States)

    Boesen, Jesper; Lithner, Johan; Palm, Torulf

    2018-01-01

    Internationally, education reform has been directed towards describing educational goals that go beyond topic and content descriptions. The idea of mathematical competencies describes such goals. National tests have been seen as one way of communicating these goals and influence teaching. The present study analyses Swedish national tests in…

  10. Mathematics

    International Nuclear Information System (INIS)

    Demazure, M.

    1988-01-01

    The 1988 progress report of the Mathematics center (Polytechnic School, France), is presented. The Center is composed of different research teams: analysis, Riemann geometry, group theory, formal calculus and algorithm geometry, dynamical systems, topology and singularity. For each team, the members, the research topics, the national and international cooperations, are given. The papers concerning the investigations carried out in 1988, are listed [fr

  11. Mathematics

    CERN Document Server

    Stein, Sherman K

    2010-01-01

    Anyone can appreciate the beauty, depth, and vitality of mathematics with the help of this highly readable text, specially developed from a college course designed to appeal to students in a variety of fields. Readers with little mathematical background are exposed to a broad range of subjects chosen from number theory, topology, set theory, geometry, algebra, and analysis. Starting with a survey of questions on weight, the text discusses the primes, the fundamental theorem of arithmetic, rationals and irrationals, tiling, tiling and electricity, probability, infinite sets, and many other topi

  12. Mathematical and theoretical neuroscience cell, network and data analysis

    CERN Document Server

    Nieus, Thierry

    2017-01-01

    This volume gathers contributions from theoretical, experimental and computational researchers who are working on various topics in theoretical/computational/mathematical neuroscience. The focus is on mathematical modeling, analytical and numerical topics, and statistical analysis in neuroscience with applications. The following subjects are considered: mathematical modelling in Neuroscience, analytical  and numerical topics;  statistical analysis in Neuroscience; Neural Networks; Theoretical Neuroscience. The book is addressed to researchers involved in mathematical models applied to neuroscience.

  13. Mathematical Methods in Survival Analysis, Reliability and Quality of Life

    CERN Document Server

    Huber, Catherine; Mesbah, Mounir

    2008-01-01

    Reliability and survival analysis are important applications of stochastic mathematics (probability, statistics and stochastic processes) that are usually covered separately in spite of the similarity of the involved mathematical theory. This title aims to redress this situation: it includes 21 chapters divided into four parts: Survival analysis, Reliability, Quality of life, and Related topics. Many of these chapters were presented at the European Seminar on Mathematical Methods for Survival Analysis, Reliability and Quality of Life in 2006.

  14. Mathematical Interventions for Secondary Students with Learning Disabilities and Mathematics Difficulties: A Meta-Analysis

    Science.gov (United States)

    Jitendra, Asha K.; Lein, Amy E.; Im, Soo-hyun; Alghamdi, Ahmed A.; Hefte, Scott B.; Mouanoutoua, John

    2018-01-01

    This meta-analysis is the first to provide a quantitative synthesis of empirical evaluations of mathematical intervention programs implemented in secondary schools for students with learning disabilities and mathematics difficulties. Included studies used a treatment-control group design. A total of 19 experimental and quasi-experimental studies…

  15. Mathematics Teaching Anxiety and Self-Efficacy Beliefs toward Mathematics Teaching: A Path Analysis

    Science.gov (United States)

    Peker, Murat

    2016-01-01

    The purpose of this study was to investigate the relationship between pre-service primary school teachers' mathematics teaching anxiety and their self-efficacy beliefs toward mathematics teaching through path analysis. There were a total of 250 pre-service primary school teachers involved in this study. Of the total, 202 were female and 48 were…

  16. Constrained mathematics evaluation in probabilistic logic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Arlin Cooper, J

    1998-06-01

    A challenging problem in mathematically processing uncertain operands is that constraints inherent in the problem definition can require computations that are difficult to implement. Examples of possible constraints are that the sum of the probabilities of partitioned possible outcomes must be one, and repeated appearances of the same variable must all have the identical value. The latter, called the 'repeated variable problem', will be addressed in this paper in order to show how interval-based probabilistic evaluation of Boolean logic expressions, such as those describing the outcomes of fault trees and event trees, can be facilitated in a way that can be readily implemented in software. We will illustrate techniques that can be used to transform complex constrained problems into trivial problems in most tree logic expressions, and into tractable problems in most other cases.

  17. Mathematical foundations of time series analysis a concise introduction

    CERN Document Server

    Beran, Jan

    2017-01-01

    This book provides a concise introduction to the mathematical foundations of time series analysis, with an emphasis on mathematical clarity. The text is reduced to the essential logical core, mostly using the symbolic language of mathematics, thus enabling readers to very quickly grasp the essential reasoning behind time series analysis. It appeals to anybody wanting to understand time series in a precise, mathematical manner. It is suitable for graduate courses in time series analysis but is equally useful as a reference work for students and researchers alike.

  18. Handbook of mathematical analysis in mechanics of viscous fluids

    CERN Document Server

    Novotný, Antonín

    2018-01-01

    Mathematics has always played a key role for researches in fluid mechanics. The purpose of this handbook is to give an overview of items that are key to handling problems in fluid mechanics. Since the field of fluid mechanics is huge, it is almost impossible to cover many topics. In this handbook, we focus on mathematical analysis on viscous Newtonian fluid. The first part is devoted to mathematical analysis on incompressible fluids while part 2 is devoted to compressible fluids.

  19. Novel mathematical algorithm for pupillometric data analysis.

    Science.gov (United States)

    Canver, Matthew C; Canver, Adam C; Revere, Karen E; Amado, Defne; Bennett, Jean; Chung, Daniel C

    2014-01-01

    Pupillometry is used clinically to evaluate retinal and optic nerve function by measuring pupillary response to light stimuli. We have developed a mathematical algorithm to automate and expedite the analysis of non-filtered, non-calculated pupillometric data obtained from mouse pupillary light reflex recordings, obtained from dynamic pupillary diameter recordings following exposure of varying light intensities. The non-filtered, non-calculated pupillometric data is filtered through a low pass finite impulse response (FIR) filter. Thresholding is used to remove data caused by eye blinking, loss of pupil tracking, and/or head movement. Twelve physiologically relevant parameters were extracted from the collected data: (1) baseline diameter, (2) minimum diameter, (3) response amplitude, (4) re-dilation amplitude, (5) percent of baseline diameter, (6) response time, (7) re-dilation time, (8) average constriction velocity, (9) average re-dilation velocity, (10) maximum constriction velocity, (11) maximum re-dilation velocity, and (12) onset latency. No significant differences were noted between parameters derived from algorithm calculated values and manually derived results (p ≥ 0.05). This mathematical algorithm will expedite endpoint data derivation and eliminate human error in the manual calculation of pupillometric parameters from non-filtered, non-calculated pupillometric values. Subsequently, these values can be used as reference metrics for characterizing the natural history of retinal disease. Furthermore, it will be instrumental in the assessment of functional visual recovery in humans and pre-clinical models of retinal degeneration and optic nerve disease following pharmacological or gene-based therapies. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Mathematical theory of compressible viscous fluids analysis and numerics

    CERN Document Server

    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...

  1. Mathematical Modelling Research in Turkey: A Content Analysis Study

    Science.gov (United States)

    Çelik, H. Coskun

    2017-01-01

    The aim of the present study was to examine the mathematical modelling studies done between 2004 and 2015 in Turkey and to reveal their tendencies. Forty-nine studies were selected using purposeful sampling based on the term, "mathematical modelling" with Higher Education Academic Search Engine. They were analyzed with content analysis.…

  2. Mathematical modeling models, analysis and applications

    CERN Document Server

    Banerjee, Sandip

    2014-01-01

    ""…the reader may find quite a few interesting examples illustrating several important methods used in applied mathematics. … it may be well used as a valuable source of interesting examples as well as complementary reading in a number of courses.""-Svitlana P. Rogovchenko, Zentralblatt MATH 1298

  3. Mathematical principles of signal processing Fourier and wavelet analysis

    CERN Document Server

    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...

  4. Fat stigmatization in television shows and movies: a content analysis.

    Science.gov (United States)

    Himes, Susan M; Thompson, J Kevin

    2007-03-01

    To examine the phenomenon of fat stigmatization messages presented in television shows and movies, a content analysis was used to quantify and categorize fat-specific commentary and humor. Fat stigmatization vignettes were identified using a targeted sampling procedure, and 135 scenes were excised from movies and television shows. The material was coded by trained raters. Reliability indices were uniformly high for the seven categories (percentage agreement ranged from 0.90 to 0.98; kappas ranged from 0.66 to 0.94). Results indicated that fat stigmatization commentary and fat humor were often verbal, directed toward another person, and often presented directly in the presence of the overweight target. Results also indicated that male characters were three times more likely to engage in fat stigmatization commentary or fat humor than female characters. To our knowledge, these findings provide the first information regarding the specific gender, age, and types of fat stigmatization that occur frequently in movies and television shows. The stimuli should prove useful in future research examining the role of individual difference factors (e.g., BMI) in the reaction to viewing such vignettes.

  5. Topics in algebra and analysis preparing for the mathematical olympiad

    CERN Document Server

    Bulajich Manfrino, Radmila; Valdez Delgado, Rogelio

    2015-01-01

    The techniques presented here are useful for solving mathematical contest problems in algebra and analysis. Most of the examples and exercises that appear in the book originate from mathematical Olympiad competitions around the world. In the first four chapters the authors cover material for competitions at high school level. The level advances with the chapters. The topics explored include polynomials, functional equations, sequences and an elementary treatment of complex numbers. The final chapters provide a comprehensive list of problems posed at national and international contests in recent years, and solutions to all exercises and problems presented in the book. It helps students in preparing for national and international mathematical contests form high school level to more advanced competitions and will also be useful for their first year of mathematical studies at the university. It will be of interest to teachers in college and university level, and trainers of the mathematical Olympiads.

  6. A Comparative Analysis of Quadratics Unit in Singaporean, Turkish and IBDP Mathematics Textbooks

    Directory of Open Access Journals (Sweden)

    Reyhan Sağlam

    2012-12-01

    Full Text Available The purpose of this study was to analyze and compare the contents of the chapters on quadratics in three mathematics textbooks selected from Turkey, Singapore, and the International Baccalaureate Diploma Program (IBDP through content analysis. The analysis of mathematical content showed that the three textbooks have different approaches and priorities in terms of the positions of chapters and weights of the quadratics units, and the time allocated to them within the respective curricular programs. It was also found that the Turkish textbook covers a greater number of learning outcomes targeted for quadratics among the three mathematics syllabi, showing a detailed treatment of the topic compared to the other two textbooks.Key Words: Content analysis, international comparative studies, mathematics textbooks

  7. The application of new mathematical structures to safety analysis

    International Nuclear Information System (INIS)

    Cooper, J.A.; Ross, T.J.

    1997-10-01

    Probabilistic safety analyses (PSAs) often depend on significant subjectivity. The recent successes of fuzzy logic and fuzzy and hybrid mathematics in portraying subjectivity is a reminder that a selection made from the most applicable mathematical tools is more important than forced adaptation of conventional tools. In this paper, the authors consider new approaches that enhance conventional and fuzzy PSA by improved handling of subjectivity. The most significant of the mathematical structures were have investigated (from a standpoint of safety analysis applications) will be described, and the general types of applications will be outlined

  8. Functional analysis in modern applied mathematics

    CERN Document Server

    Curtain, Ruth F

    1977-01-01

    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

  9. Error analysis of mathematical problems on TIMSS: A case of Indonesian secondary students

    Science.gov (United States)

    Priyani, H. A.; Ekawati, R.

    2018-01-01

    Indonesian students’ competence in solving mathematical problems is still considered as weak. It was pointed out by the results of international assessment such as TIMSS. This might be caused by various types of errors made. Hence, this study aimed at identifying students’ errors in solving mathematical problems in TIMSS in the topic of numbers that considered as the fundamental concept in Mathematics. This study applied descriptive qualitative analysis. The subject was three students with most errors in the test indicators who were taken from 34 students of 8th graders. Data was obtained through paper and pencil test and student’s’ interview. The error analysis indicated that in solving Applying level problem, the type of error that students made was operational errors. In addition, for reasoning level problem, there are three types of errors made such as conceptual errors, operational errors and principal errors. Meanwhile, analysis of the causes of students’ errors showed that students did not comprehend the mathematical problems given.

  10. Operator Semigroups meet Complex Analysis, Harmonic Analysis and Mathematical Physics

    CERN Document Server

    Chill, Ralph; Tomilov, Yuri

    2015-01-01

    This proceedings volume originates from a conference held in Herrnhut in June 2013. It provides unique insights into the power of abstract methods and techniques in dealing successfully with numerous applications stemming from classical analysis and mathematical physics. The book features diverse topics in the area of operator semigroups, including partial differential equations, martingale and Hilbert transforms, Banach and von Neumann algebras, Schrödinger operators, maximal regularity and Fourier multipliers, interpolation, operator-theoretical problems (concerning generation, perturbation and dilation, for example), and various qualitative and quantitative Tauberian theorems with a focus on transfinite induction and magics of Cantor. The last fifteen years have seen the dawn of a new era for semigroup theory with the emphasis on applications of abstract results, often unexpected and far removed from traditional ones. The aim of the conference was to bring together prominent experts in the field of modern...

  11. Analysis of mathematical modelling on potentiometric biosensors.

    Science.gov (United States)

    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.

  12. Advertising Discourse Analysis of FES stores: Killing Love, Cowards Show

    Directory of Open Access Journals (Sweden)

    Cristian Venegas Ahumada

    2013-08-01

    Full Text Available The objective is to analyze the structural and photographic discourse of the Autumn-Winter campaign 2008 of FES stores for young people. This was done by a semiotic theory and a critical-structural methodology of discourse. An analysis of 4 advertising photographs was done, and at once an analysis of the discourse “FES says no to violence against Women”, which explains the campaign’s target. The result is: The discourse was subjected to production condition (society of control and makes advertising a way to homogenize subjectivity of masses to consume. Recognition conditions demonstrate that this advertising discourse of symbolic violence means a type of violation of Men and Women Rights. An action like this requires commitment of Psychology in order to promote the social humanizing change, by means of university teaching and professional tasks.

  13. Mathematical methods in time series analysis and digital image processing

    CERN Document Server

    Kurths, J; Maass, P; Timmer, J

    2008-01-01

    The aim of this volume is to bring together research directions in theoretical signal and imaging processing developed rather independently in electrical engineering, theoretical physics, mathematics and the computer sciences. In particular, mathematically justified algorithms and methods, the mathematical analysis of these algorithms, and methods as well as the investigation of connections between methods from time series analysis and image processing are reviewed. An interdisciplinary comparison of these methods, drawing upon common sets of test problems from medicine and geophysical/enviromental sciences, is also addressed. This volume coherently summarizes work carried out in the field of theoretical signal and image processing. It focuses on non-linear and non-parametric models for time series as well as on adaptive methods in image processing.

  14. Bayesian analysis of repairable systems showing a bounded failure intensity

    International Nuclear Information System (INIS)

    Guida, Maurizio; Pulcini, Gianpaolo

    2006-01-01

    The failure pattern of repairable mechanical equipment subject to deterioration phenomena sometimes shows a finite bound for the increasing failure intensity. A non-homogeneous Poisson process with bounded increasing failure intensity is then illustrated and its characteristics are discussed. A Bayesian procedure, based on prior information on model-free quantities, is developed in order to allow technical information on the failure process to be incorporated into the inferential procedure and to improve the inference accuracy. Posterior estimation of the model-free quantities and of other quantities of interest (such as the optimal replacement interval) is provided, as well as prediction on the waiting time to the next failure and on the number of failures in a future time interval is given. Finally, numerical examples are given to illustrate the proposed inferential procedure

  15. Making Culturally Responsive Mathematics Teaching Explicit: A Lesson Analysis Tool

    Science.gov (United States)

    Aguirre, Julia M.; Zavala, Maria del Rosario

    2013-01-01

    In the United States, there is a need for pedagogical tools that help teachers develop essential pedagogical content knowledge and practices to meet the mathematical education needs of a growing culturally and linguistically diverse student population. In this article, we introduce an innovative lesson analysis tool that focuses on integrating…

  16. Mathematical annuity models application in cash flow analysis ...

    African Journals Online (AJOL)

    Mathematical annuity models application in cash flow analysis. ... We also compare the cost efficiency between Amortisation and Sinking fund loan repayment as prevalent in financial institutions. Keywords: Annuity, Amortisation, Sinking Fund, Present and Future Value Annuity, Maturity date and Redemption value.

  17. Mathematical model for safety analysis of heavy water power reactor

    International Nuclear Information System (INIS)

    Milovanovic, M.; Humo, E.; Mitrovic, S.

    1966-01-01

    Fundamental information in formulating the mathematical model for accident analysis is concerned with reactivity changes of the system. These parameters are: changes of fuel and moderator temperature, changes of the upper reflector thickness, reactivity changes due to moderator density variation dependent on the steam quantity and neutron flux distribution in the core

  18. A Mathematical Model for Analysis on Ships Collision Avoidance ...

    African Journals Online (AJOL)

    This study develops a mathematical model for analysis on collision avoidance of ships. The obtained model provides information on the quantitative effect of the ship's engine's response and the applied reversing force on separation distance and stopping abilities of the ships. Appropriate evasive maneuvers require the ...

  19. A REVIEW AND CONTENT ANALYSIS OF MATHEMATICS TEXTBOOKS IN EDUCATIONAL RESEARCH

    Directory of Open Access Journals (Sweden)

    Cheng Chieh Chang

    2017-06-01

    Full Text Available Research collected and reviewed a number of empirical studies in the field of educational research regarding the analysis of mathematics textbooks to provide summary and overview the information there in. The questions were identified via Google Scholar and collected from different data sources. A total of 44 papers published from 1953 to 2015 were selected based specific criteria, with 24 articles include in the SSCI database. Descriptive statistics were used to evaluate and interpret the results. A perspective on the learning analysis methods was used to collect studies and showed the mathematics textbooks analyzed were investigated under four themes: The analysis of standards, distributive property, language in mathematics, and others. School’s level which is investigated textbooks: Kindergarten, elementary, junior school, and senior school. Subjects covered in the mathematics textbooks included algebra and arithmetic, geometry, measurement, data analysis and probability, number and operations, among others. Research found the most frequently discussed in perspective on learning was the analysis of the standards and the distributive property (15 studies, the most common subject was number and operations (16 studies, and the highest number in school’s level was elementary school (18 studies. Nevertheless, fewer studies have been found to analyzing mathematics textbooks. Future research can pay attention for the relevant theoretical issues and collaborate studies in more perspective learning analysis.

  20. Ten mathematical essays on approximation in analysis and topology

    CERN Document Server

    López-Gómez, J; Ruiz del Portal, F R

    2005-01-01

    This book collects 10 mathematical essays on approximation in Analysis and Topology by some of the most influent mathematicians of the last third of the 20th Century. Besides the papers contain the very ultimate results in each of their respective fields, many of them also include a series of historical remarks about the state of mathematics at the time they found their most celebrated results, as well as some of their personal circumstances originating them, which makes particularly attractive the book for all scientist interested in these fields, from beginners to experts. These gem pieces

  1. Wavelet methods in mathematical analysis and engineering

    CERN Document Server

    Damlamian, Alain

    2010-01-01

    This book gives a comprehensive overview of both the fundamentals of wavelet analysis and related tools, and of the most active recent developments towards applications. It offers a stateoftheart in several active areas of research where wavelet ideas, or more generally multiresolution ideas have proved particularly effective. The main applications covered are in the numerical analysis of PDEs, and signal and image processing. Recently introduced techniques such as Empirical Mode Decomposition (EMD) and new trends in the recovery of missing data, such as compressed sensing, are also presented.

  2. Mathematical modeling and analysis of WEDM machining ...

    Indian Academy of Sciences (India)

    M P GARG

    analysis and optimization of the WEDM process parameters of Inconel 625. The four ... fields such as aerospace, missile, and nuclear industry, very complex and ... piping, the alloy continues to find new application and ... automobile, chemical processing, oil refining, marine, ... Inconel 625 is a material of choice for gas.

  3. The Mathematical Analysis of the Within-Host Dynamics of ...

    African Journals Online (AJOL)

    We analyze a mathematical model of within-host dynamics of plasmodium falciparum. We report that there are two critical points the infection-free equilibrium point and the infection equilibrium point. We show that the infection – free equilibrium is asymptotically stable if the reproduction number R0 1 ...

  4. The natural mathematics of behavior analysis.

    Science.gov (United States)

    Li, Don; Hautus, Michael J; Elliffe, Douglas

    2018-04-19

    Models that generate event records have very general scope regarding the dimensions of the target behavior that we measure. From a set of predicted event records, we can generate predictions for any dependent variable that we could compute from the event records of our subjects. In this sense, models that generate event records permit us a freely multivariate analysis. To explore this proposition, we conducted a multivariate examination of Catania's Operant Reserve on single VI schedules in transition using a Markov Chain Monte Carlo scheme for Approximate Bayesian Computation. Although we found systematic deviations between our implementation of Catania's Operant Reserve and our observed data (e.g., mismatches in the shape of the interresponse time distributions), the general approach that we have demonstrated represents an avenue for modelling behavior that transcends the typical constraints of algebraic models. © 2018 Society for the Experimental Analysis of Behavior.

  5. Analysis of anatomic variability in children with low mathematical skills

    Science.gov (United States)

    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.

  6. Analysis mathematical literacy skills in terms of the students’ metacognition on PISA-CPS model

    Science.gov (United States)

    Ovan; Waluya, S. B.; Nugroho, S. E.

    2018-03-01

    This research was aimed to know the effectiveness of PISA-CPS model and desceibe the mathematical literacy skills (KLM) in terms of the students’ metacognition. This study used Mixed Methods approaches with the concurrent embedded desaign. The technique of data analysis on quantitative research done analysis of lesson plan, prerequisite test, test hypotesis 1 and hypotesis test. While qualitative research done data reduction, data presentation, and drawing conclution and data verification. The subject of this study was the students of Grade Eight (VIII) of SMP Islam Sultan Agung 4 Semarang, Central Java. The writer analyzed the data with quantitative and qualitative approaches based on the metacognition of the students in low, medium and high groups. Subsequently, taken the mathematical literacy skills (KLM) from students’ metacognition in low, medium, and high . The results of the study showed that the PISA-CPS model was complete and the students’ mathematical literacy skills in terms of the students’ metacognition taught by the PISA-CPS model was higher than the expository learning. metacognitions’ students classified low hadmathematical literacy skills (KLM) less good, metacognitions’ students classified medium had mathematical literacy skills (KLM) good enough, metacognitions’ students classified high had mathematical literacy skills (KLM) very good. Based onresult analysis got conclusion that the PISA-CPS model was effective toward the students’ mathematical literacy skills (KLM). To increase the students’ mathematical literacy skills (KLM), the teachers need to provide reinforcements in the form of the exercises so that the student’s mathematical literacy was achieved at level 5 and level 6.

  7. Attitude Determination Error Analysis System (ADEAS) mathematical specifications document

    Science.gov (United States)

    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.

  8. Mathematical Analysis of Urban Spatial Networks

    CERN Document Server

    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.

  9. Mathematical models of ABE fermentation: review and analysis.

    Science.gov (United States)

    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.

  10. Mathematical analysis of dengue virus antibody dynamics

    Science.gov (United States)

    Perera, Sulanie; Perera, SSN

    2018-03-01

    Dengue is a mosquito borne viral disease causing over 390 million infections worldwide per annum. Even though information on how infection is controlled and eradicated from the body is lacking, antibodies are thought to play a major role in clearing the virus. In this paper, a non-linear conceptual dynamical model with humoral immune response and absorption effect has been proposed for primary dengue infection. We have included the absorption of pathogens into uninfected cells since this effect causes the virus density in the blood to decrease. The time delay that arises in the production of antibodies was accounted and is introduced through a continuous function. The basic reproduction number R0 is computed and a detailed stability analysis is done. Three equilibrium states, namely the infection free equilibrium, no immune equilibrium and the endemic equilibrium were identified and the existence and the stability conditions of these steady states were obtained. Numerical simulations proved the results that were obtained. By establishing the characteristic equation of the model at infection free equilibrium, it was observed that the infection free equilibrium is locally asymptotically stable if R0 1. Stability regions are identified for infection free equilibrium state with respect to the external variables and it is observed as the virus burst rate increases, the stability regions would decrease. These results implied that for higher virus burst rates, other conditions in the body must be strong enough to eliminate the disease completely from the host. The effect of time delay of antibody production on virus dynamics is discussed. It was seen that as the time delay in production of antibodies increases, the time for viral decline also increased. Also it was observed that the virus count goes to negligible levels within 7 - 14 days after the onset of symptoms as seen in dengue infections.

  11. Time-frequency analysis : mathematical analysis of the empirical mode decomposition.

    Science.gov (United States)

    2009-01-01

    Invented over 10 years ago, empirical mode : decomposition (EMD) provides a nonlinear : time-frequency analysis with the ability to successfully : analyze nonstationary signals. Mathematical : Analysis of the Empirical Mode Decomposition : is a...

  12. [Relations between biomedical variables: mathematical analysis or linear algebra?].

    Science.gov (United States)

    Hucher, M; Berlie, J; Brunet, M

    1977-01-01

    The authors, after a short reminder of one pattern's structure, stress on the possible double approach of relations uniting the variables of this pattern: use of fonctions, what is within the mathematical analysis sphere, use of linear algebra profiting by matricial calculation's development and automatiosation. They precise the respective interests on these methods, their bounds and the imperatives for utilization, according to the kind of variables, of data, and the objective for work, understanding phenomenons or helping towards decision.

  13. Research in applied mathematics, numerical analysis, and computer science

    Science.gov (United States)

    1984-01-01

    Research conducted at the Institute for Computer Applications in Science and Engineering (ICASE) in applied mathematics, numerical analysis, and computer science is summarized and abstracts of published reports are presented. The major categories of the ICASE research program are: (1) numerical methods, with particular emphasis on the development and analysis of basic numerical algorithms; (2) control and parameter identification; (3) computational problems in engineering and the physical sciences, particularly fluid dynamics, acoustics, and structural analysis; and (4) computer systems and software, especially vector and parallel computers.

  14. Stories about Math: An Analysis of Students' Mathematical Autobiographies

    Science.gov (United States)

    Latterell, Carmen M.; Wilson, Janelle L.

    2016-01-01

    This paper analyzes 16 preservice secondary mathematics education majors' mathematical autobiographies. Participants wrote about their previous experiences with mathematics. All participants discussed why they wanted to become mathematics teachers with the key factors being past experience with mathematics teachers, previous success in mathematics…

  15. Methods of Approximation Theory in Complex Analysis and Mathematical Physics

    CERN Document Server

    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. ...

  16. Understanding intratumor heterogeneity by combining genome analysis and mathematical modeling.

    Science.gov (United States)

    Niida, Atsushi; Nagayama, Satoshi; Miyano, Satoru; Mimori, Koshi

    2018-04-01

    Cancer is composed of multiple cell populations with different genomes. This phenomenon called intratumor heterogeneity (ITH) is supposed to be a fundamental cause of therapeutic failure. Therefore, its principle-level understanding is a clinically important issue. To achieve this goal, an interdisciplinary approach combining genome analysis and mathematical modeling is essential. For example, we have recently performed multiregion sequencing to unveil extensive ITH in colorectal cancer. Moreover, by employing mathematical modeling of cancer evolution, we demonstrated that it is possible that this ITH is generated by neutral evolution. In this review, we introduce recent advances in a research field related to ITH and also discuss strategies for exploiting novel findings on ITH in a clinical setting. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  17. Pest control through viral disease: mathematical modeling and analysis.

    Science.gov (United States)

    Bhattacharyya, S; Bhattacharya, D K

    2006-01-07

    This paper deals with the mathematical modeling of pest management under viral infection (i.e. using viral pesticide) and analysis of its essential mathematical features. As the viral infection induces host lysis which releases more virus into the environment, on the average 'kappa' viruses per host, kappain(1,infinity), the 'virus replication parameter' is chosen as the main parameter on which the dynamics of the infection depends. We prove that there exists a threshold value kappa(0) beyond which the endemic equilibrium bifurcates from the free disease one. Still for increasing kappa values, the endemic equilibrium bifurcates towards a periodic solution. We further analyse the orbital stability of the periodic orbits arising from bifurcation by applying Poor's condition. A concluding discussion with numerical simulation of the model is then presented.

  18. Mathematical competencies and the role of mathematics in physics education: A trend analysis of TIMSS Advanced 1995 and 2008

    Directory of Open Access Journals (Sweden)

    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.

  19. Mathematical biology

    CERN Document Server

    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...

  20. Three dimensional mathematical model of tooth for finite element analysis

    Directory of Open Access Journals (Sweden)

    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.

  1. Applying an alternative mathematics pedagogy for students with weak mathematics: meta-analysis of alternative pedagogies

    Science.gov (United States)

    Lake, Warren; Wallin, Margie; Woolcott, Geoff; Boyd, Wendy; Foster, Alan; Markopoulos, Christos; Boyd, William

    2017-02-01

    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 undertaken of identified innovations and/or interventions that may lead to improvement in student outcomes for university mathematics-based units of study. The review revealed the importance of understanding the foundations of student performance in higher education mathematics learning, especially in first year. Pre-university mathematics skills were identified as significant in student retention and mathematics success at university, and a specific focus on student pre-university mathematics skill level was found to be more effective in providing help, rather than simply focusing on a particular at-risk group. Diagnostics tools were found to be important in identifying (1) student background and (2) appropriate intervention. The studies highlighted the importance of appropriate and validated interventions in mathematics teaching and learning, and the need to improve the learning model for mathematics-based subjects, communication and technology innovations.

  2. Toward an Analysis of Video Games for Mathematics Education

    Science.gov (United States)

    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…

  3. ANALYSIS MUSIC CONCERTS ADOPTING THE MATHEMATICAL MODEL OF HIT PHENOMENA

    OpenAIRE

    Kawahata Yasuko; Genda Etsuo; Ishii Akira

    2013-01-01

    A mathematical model for the hit phenomenon in entertainment within a society is presented as a stochastic process of interactions of human dynamics. In this paper, we analyzed music to the concert.Knowing the cost of advertising the concert is difficult. But exposure to the media of the artist can be seen. We tried to analysis of music concert itself by performing a prediction of reputation of artists during the concert tour from this exposure.In this paper, The world most pop...

  4. The analysis of mathematics teachers' learning on algebra function limit material based on teaching experience difference

    Science.gov (United States)

    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.

  5. A Meta-Analysis of Mathematics and Working Memory: Moderating Effects of Working Memory Domain, Type of Mathematics Skill, and Sample Characteristics

    Science.gov (United States)

    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…

  6. Protocol Analysis of Group Problem Solving in Mathematics: A Cognitive-Metacognitive Framework for Assessment.

    Science.gov (United States)

    Artzt, Alice F.; Armour-Thomas, Eleanor

    The roles of cognition and metacognition were examined in the mathematical problem-solving behaviors of students as they worked in small groups. As an outcome, a framework that links the literature of cognitive science and mathematical problem solving was developed for protocol analysis of mathematical problem solving. Within this framework, each…

  7. Pedagogical Applications from Real Analysis for Secondary Mathematics Teachers

    Science.gov (United States)

    Wasserman, Nicholas; Weber, Keith

    2017-01-01

    In this article, we consider the potential influences of the study of proofs in advanced mathematics on secondary mathematics teaching. Thus far, the literature has highlighted the benefits of applying the conclusions of particular proofs to secondary content and of developing a more general sense of disciplinary practices in mathematics in…

  8. A Cognitive Analysis of Students’ Mathematical Problem Solving Ability on Geometry

    Science.gov (United States)

    Rusyda, N. A.; Kusnandi, K.; Suhendra, S.

    2017-09-01

    The purpose of this research is to analyze of mathematical problem solving ability of students in one of secondary school on geometry. This research was conducted by using quantitative approach with descriptive method. Population in this research was all students of that school and the sample was twenty five students that was chosen by purposive sampling technique. Data of mathematical problem solving were collected through essay test. The results showed the percentage of achievement of mathematical problem solving indicators of students were: 1) solve closed mathematical problems with context in math was 50%; 2) solve the closed mathematical problems with the context beyond mathematics was 24%; 3) solving open mathematical problems with contexts in mathematics was 35%; And 4) solving open mathematical problems with contexts outside mathematics was 44%. Based on the percentage, it can be concluded that the level of achievement of mathematical problem solving ability in geometry still low. This is because students are not used to solving problems that measure mathematical problem solving ability, weaknesses remember previous knowledge, and lack of problem solving framework. So the students’ ability of mathematical problems solving need to be improved with implement appropriate learning strategy.

  9. Computational mathematics models, methods, and analysis with Matlab and MPI

    CERN Document Server

    White, Robert E

    2004-01-01

    Computational Mathematics: Models, Methods, and Analysis with MATLAB and MPI explores and illustrates this process. Each section of the first six chapters is motivated by a specific application. The author applies a model, selects a numerical method, implements computer simulations, and assesses the ensuing results. These chapters include an abundance of MATLAB code. By studying the code instead of using it as a "black box, " you take the first step toward more sophisticated numerical modeling. The last four chapters focus on multiprocessing algorithms implemented using message passing interface (MPI). These chapters include Fortran 9x codes that illustrate the basic MPI subroutines and revisit the applications of the previous chapters from a parallel implementation perspective. All of the codes are available for download from www4.ncsu.edu./~white.This book is not just about math, not just about computing, and not just about applications, but about all three--in other words, computational science. Whether us...

  10. Mathematical analysis of dynamic spread of Pine Wilt disease.

    Science.gov (United States)

    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.

  11. Mathematical analysis of the multiband BCS gap equations in superconductivity

    Science.gov (United States)

    Yang, Yisong

    2005-01-01

    In this paper, we present a mathematical analysis for the phonon-dominated multiband isotropic and anisotropic BCS gap equations at any finite temperature T. We establish the existence of a critical temperature T so that, when TT, the only nonnegative gap solution is the zero solution, representing the normal phase. Furthermore, when T=T, we prove that the only gap solution is the zero solution and that the positive gap solution depend on the temperature TMarkowitz-Kadanoff model and we prove that the presence of anisotropic fluctuations enhances T as in the single-band case. A special consequence of these results is that the half-unity exponent isotope effect may rigorously be proved in the multiband BCS theory, isotropic or anisotropic.

  12. LATENT CLUSTER ANALYSIS OF INSTRUCTIONAL PRACTICES REPORTED BY HIGH- AND LOW-PERFORMING MATHEMATICS TEACHERS IN FOUR COUNTRIES

    Directory of Open Access Journals (Sweden)

    Qiang Cheng

    2017-06-01

    Full Text Available Using Trends in International Mathematics and Science Study (TIMSS 2011 eighth-grade international dataset, this study explored the profiles of instructional practices reported by high- and low-performing mathematics teachers across the US, Finland, Korea, and Russia. Concepts of conceptual teaching and procedural teaching were used to frame the design of the current study. Latent cluster analysis was applied in the investigation of the profiles of mathematics teachers’ instructional practices across the four education systems. It was found that all mathematics teachers in the high- and low-performing groups used procedurally as well as conceptually oriented practices in their teaching. However, one group of high-performing mathematics teachers from the U.S. sample and all the high-performing teachers from Finland, Korea, and Russia showed more frequent use of conceptually oriented practices than their corresponding low-performing teachers. Another group of U.S. high-performing mathematics teachers showed a distinctive procedurally oriented pattern, which presented a rather different picture. Such results provide useful suggestions for practitioners and policy makers in their effort to improve mathematics teaching and learning in the US and in other countries as well.DOI: http://dx.doi.org/10.22342/jme.8.2.4066.115-132

  13. A Cognitive Analysis of Students’ Mathematical Communication Ability on Geometry

    Science.gov (United States)

    Sari, D. S.; Kusnandi, K.; Suhendra, S.

    2017-09-01

    This study aims to analyze the difficulties of mathematical communication ability of students in one of secondary school on “three-dimensional space” topic. This research conducted by using quantitative approach with descriptive method. The population in this research was all students of that school and the sample was thirty students that was chosen by purposive sampling technique. Data of mathematical communication were collected through essay test. Furthermore, the data were analyzed with a descriptive way. The results of this study indicate that the percentage of achievement of student mathematical communication indicators as follows 1) Stating a situation, ideas, and mathematic correlation into images, graphics, or algebraic expressions is 35%; 2) Stating daily experience into a mathematic language / symbol, or a mathematic model is 35%; and 3) Associating images or diagrams into mathematical ideas is 53.3%. Based on the percentage of achievement on each indicator, it can be concluded that the level of achievement of students’ mathematical communication ability is still low. It can be caused the students were not used to convey or write their mathematical ideas systematically. Therefore students’ mathematical communication ability need to be improved.

  14. MATHEMATICAL RISK ANALYSIS: VIA NICHOLAS RISK MODEL AND BAYESIAN ANALYSIS

    Directory of Open Access Journals (Sweden)

    Anass BAYAGA

    2010-07-01

    Full Text Available The objective of this second part of a two-phased study was to explorethe predictive power of quantitative risk analysis (QRA method andprocess within Higher Education Institution (HEI. The method and process investigated the use impact analysis via Nicholas risk model and Bayesian analysis, with a sample of hundred (100 risk analysts in a historically black South African University in the greater Eastern Cape Province.The first findings supported and confirmed previous literature (KingIII report, 2009: Nicholas and Steyn, 2008: Stoney, 2007: COSA, 2004 that there was a direct relationship between risk factor, its likelihood and impact, certiris paribus. The second finding in relation to either controlling the likelihood or the impact of occurrence of risk (Nicholas risk model was that to have a brighter risk reward, it was important to control the likelihood ofoccurrence of risks as compared with its impact so to have a direct effect on entire University. On the Bayesian analysis, thus third finding, the impact of risk should be predicted along three aspects. These aspects included the human impact (decisions made, the property impact (students and infrastructural based and the business impact. Lastly, the study revealed that although in most business cases, where as business cycles considerably vary dependingon the industry and or the institution, this study revealed that, most impacts in HEI (University was within the period of one academic.The recommendation was that application of quantitative risk analysisshould be related to current legislative framework that affects HEI.

  15. International seminar series on mathematics and applied mathematics and a series of three focused international research workshops on engineering mathematics organised by the Research Environment in Mathematics and Applied Mathematics at Mälardalen University from autumn 2014 to autumn 2015: the International Workshop on Engineering Mathematics for Electromagnetics and Health Technology; the International Workshop on Engineering Mathematics, Algebra, Analysis and Electromagnetics; and the 1st Swedish-Estonian International Workshop on Engineering Mathematics, Algebra, Analysis and Applications

    CERN Document Server

    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...

  16. Mathematical Methods of System Analysis in Construction Materials

    Science.gov (United States)

    Garkina, Irina; Danilov, Alexander

    2017-10-01

    System attributes of construction materials are defined: complexity of an object, integrity of set of elements, existence of essential, stable relations between elements defining integrative properties of system, existence of structure, etc. On the basis of cognitive modelling (intensive and extensive properties; the operating parameters) materials (as difficult systems) and creation of the cognitive map the hierarchical modular structure of criteria of quality is under construction. It actually is a basis for preparation of the specification on development of material (the required organization and properties). Proceeding from a modern paradigm (model of statement of problems and their decisions) of development of materials, levels and modules are specified in structure of material. It when using the principles of the system analysis allows to considered technological process as the difficult system consisting of elements of the distinguished specification level: from atomic before separate process. Each element of system depending on an effective objective is considered as separate system with more detailed levels of decomposition. Among them, semantic and qualitative analyses of an object (are considered a research objective, decomposition levels, separate elements and communications between them come to light). Further formalization of the available knowledge in the form of mathematical models (structural identification) is carried out; communications between input and output parameters (parametrical identification) are defined. Hierarchical structures of criteria of quality are under construction for each allocated level. On her the relevant hierarchical structures of system (material) are under construction. Regularities of structurization and formation of properties, generally are considered at the levels from micro to a macrostructure. The mathematical model of material is represented as set of the models corresponding to private criteria by which separate

  17. Mathematical Model and Stability Analysis of Inverter-Based Distributed Generator

    Directory of Open Access Journals (Sweden)

    Alireza Khadem Abbasi

    2013-01-01

    Full Text Available This paper presents a mathematical (small-signal model of an electronically interfaced distributed generator (DG by considering the effect of voltage and frequency variations of the prime source. Dynamic equations are found by linearization about an operating point. In this study, the dynamic of DC part of the interface is included in the model. The stability analysis shows with proper selection of system parameters; the system is stable during steady-state and dynamic situations, and oscillatory modes are well damped. The proposed model is useful to study stability analysis of a standalone DG or a Microgrid.

  18. Mathematical analysis of compressive/tensile molecular and nuclear structures

    Science.gov (United States)

    Wang, Dayu

    Mathematical analysis in chemistry is a fascinating and critical tool to explain experimental observations. In this dissertation, mathematical methods to present chemical bonding and other structures for many-particle systems are discussed at different levels (molecular, atomic, and nuclear). First, the tetrahedral geometry of single, double, or triple carbon-carbon bonds gives an unsatisfying demonstration of bond lengths, compared to experimental trends. To correct this, Platonic solids and Archimedean solids were evaluated as atoms in covalent carbon or nitrogen bond systems in order to find the best solids for geometric fitting. Pentagonal solids, e.g. the dodecahedron and icosidodecahedron, give the best fit with experimental bond lengths; an ideal pyramidal solid which models covalent bonds was also generated. Second, the macroscopic compression/tension architectural approach was applied to forces at the molecular level, considering atomic interactions as compressive (repulsive) and tensile (attractive) forces. Two particle interactions were considered, followed by a model of the dihydrogen molecule (H2; two protons and two electrons). Dihydrogen was evaluated as two different types of compression/tension structures: a coaxial spring model and a ring model. Using similar methods, covalent diatomic molecules (made up of C, N, O, or F) were evaluated. Finally, the compression/tension model was extended to the nuclear level, based on the observation that nuclei with certain numbers of protons/neutrons (magic numbers) have extra stability compared to other nucleon ratios. A hollow spherical model was developed that combines elements of the classic nuclear shell model and liquid drop model. Nuclear structure and the trend of the "island of stability" for the current and extended periodic table were studied.

  19. Verification of temporal-causal network models by mathematical analysis

    Directory of Open Access Journals (Sweden)

    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.

  20. International Conference on Recent Advances in Mathematical Biology, Analysis and Applications

    CERN Document Server

    Saleem, M; Srivastava, H; Khan, Mumtaz; Merajuddin, M

    2016-01-01

    The book contains recent developments and contemporary research in mathematical analysis and in its application to problems arising from the biological and physical sciences. The book is of interest to readers who wish to learn of new research in such topics as linear and nonlinear analysis, mathematical biology and ecology, dynamical systems, graph theory, variational analysis and inequalities, functional analysis, differential and difference equations, partial differential equations, approximation theory, and chaos. All papers were prepared by participants at the International Conference on Recent Advances in Mathematical Biology, Analysis and Applications (ICMBAA-2015) held during 4–6 June 2015 in Aligarh, India. A focal theme of the conference was the application of mathematics to the biological sciences and on current research in areas of theoretical mathematical analysis that can be used as sophisticated tools for the study of scientific problems. The conference provided researchers, academicians and ...

  1. Mathematical and numerical analysis of hyper-elastic systems and introduction of plasticity

    International Nuclear Information System (INIS)

    Kluth, G.

    2008-12-01

    The goal is to model mathematically and numerically the dynamic phenomenons for solids in finite plasticity. We suggest a model that we call hyper-elasto-plastic based on hyper-elastic systems of conservation laws and on the use of an equation of state that we have constructed so as to achieve the plastic yield criterion of Von Mises. This model gives exact (analytic) solutions with shock split to flyer-plate experiments. The mathematical analysis of this model is done (hyperbolicity, characteristic fields, involutions and entropy). In the numerical part, we give 1D and 2D Lagrangian schemes which satisfy an entropy criterion. Moreover, thanks to a special discretization of the equations on deformation gradient, we satisfy some discrete involutions. In this work, the degeneracy of the solid model into hydrodynamic models is studied at the continuous level, and achieved at the numerical one. On different problems, we show the validity of our model and our numerical schemes. (author)

  2. Critical analysis of the policy practice of mathematics education in ...

    African Journals Online (AJOL)

    Ensuring a smooth mathematics education programme requires the formulation and implementation of appropriate instructional policies. This study is a survey of some practices of the instructional policies and their influence on mathematics education. Completed Basic School Annual Census (CBSAC) forms and ...

  3. Mathematical analysis and numerical methods for science and technology

    CERN Document Server

    Dautray, Robert

    These 6 volumes - the result of a 10 year collaboration between the authors, two of France's leading scientists and both distinguished international figures - compile the mathematical knowledge required by researchers in mechanics, physics, engineering, chemistry and other branches of application of mathematics for the theoretical and numerical resolution of physical models on computers. Since the publication in 1924 of the "Methoden der mathematischen Physik" by Courant and Hilbert, there has been no other comprehensive and up-to-date publication presenting the mathematical tools needed in applications of mathematics in directly implementable form. The advent of large computers has in the meantime revolutionised methods of computation and made this gap in the literature intolerable: the objective of the present work is to fill just this gap. Many phenomena in physical mathematics may be modeled by a system of partial differential equations in distributed systems: a model here means a set of equations, which ...

  4. Importance Performance Analysis as a Trade Show Performance Evaluation and Benchmarking Tool

    OpenAIRE

    Tafesse, Wondwesen; Skallerud, Kåre; Korneliussen, Tor

    2010-01-01

    Author's accepted version (post-print). The purpose of this study is to introduce importance performance analysis as a trade show performance evaluation and benchmarking tool. Importance performance analysis considers exhibitors’ performance expectation and perceived performance in unison to evaluate and benchmark trade show performance. The present study uses data obtained from exhibitors of an international trade show to demonstrate how importance performance analysis can be used to eval...

  5. The analysis of mathematics literacy on PMRI learning with media schoology of junior high school students

    Science.gov (United States)

    Wardono; Mariani, S.

    2018-03-01

    Indonesia as a developing country in the future will have high competitiveness if its students have high mathematics literacy ability. The current reality from year to year rankings of PISA mathematics literacy Indonesian students are still not good. This research is motivated by the importance and low ability of the mathematics literacy. The purpose of this study is to: (1) analyze the effectiveness of PMRI learning with media Schoology, (2) describe the ability of students' mathematics literacy on PMRI learning with media Schoology which is reviewed based on seven components of mathematics literacy, namely communication, mathematizing, representation, reasoning, devising strategies, using symbols, and using mathematics tool. The method used in this research is the method of sequential design method mix. Techniques of data collection using observation, interviews, tests, and documentation. Data analysis techniques use proportion test, appellate test, and use descriptive analysis. Based on the data analysis, it can be concluded; (1) PMRI learning with media Schoology effectively improve the ability of mathematics literacy because of the achievement of classical completeness, students' mathematics literacy ability in PMRI learning with media Schoology is higher than expository learning, and there is increasing ability of mathematics literacy in PMRI learning with media Schoology of 30%. (2) Highly capable students attain excellent mathematics literacy skills, can work using broad thinking with appropriate resolution strategies. Students who are capable of achieving good mathematics literacy skills can summarize information, present problem-solving processes, and interpret solutions. low-ability students have reached the level of ability of mathematics literacy good enough that can solve the problem in a simple way.

  6. Mathematical Model and Analysis of Negative Skin Friction of Pile Group in Consolidating Soil

    Directory of Open Access Journals (Sweden)

    Gangqiang Kong

    2013-01-01

    Full Text Available In order to calculate negative skin friction (NSF of pile group embedded in a consolidating soil, the dragload calculating formulas of single pile were established by considering Davis one-dimensional nonlinear consolidation soils settlement and hyperbolic load-transfer of pile-soil interface. Based on effective influence area theory, a simple semiempirical mathematical model of analysis for predicting the group effect of pile group under dragload was described. The accuracy and reliability of mathematical models built in this paper were verified by practical engineering comparative analysis. Case studies were studied, and the prediction values were found to be in good agreement with those of measured values. Then, the influences factors, such as, soil consolidation degree, the initial volume compressibility coefficient, and the stiffness of bearing soil, were analyzed and discussed. The results show that the mathematical models considering nonlinear soil consolidation and group effect can reflect the practical NSF of pile group effectively and accurately. The results of this paper can provide reference for practical pile group embedded in consolidating soil under NSF design and calculation.

  7. [Representation and mathematical analysis of human crystalline lens].

    Science.gov (United States)

    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.

  8. A Mathematical Analysis of Intravitreal Drug Transport | Avtar ...

    African Journals Online (AJOL)

    Method: A simple mathematical model for the intravitreal transport of drugs was developed ... of the equation describing the drug transport in the vitreous body was written, in which the ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  9. Stability Analysis of a Mathematical Model for Onchocerciaisis ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: In this work, we propose a Deterministic Mathematical Model that ... blackflies Center for Disease Control and World ... villages located along fast flowing rivers where the ..... distribution of Blackflies (Simulium Species) in.

  10. Analysis of students’ self-determination in learning mathematics

    Science.gov (United States)

    Wilujeng, H.

    2018-01-01

    Self-determination (SDT) is the ability in identifying and achieving the purpose based on knowledge and the assessment of the individual against himself. Three aspects in the SDT includes autonomy, competence and relationships become an important part for students to be able to understand the capabilities of themselves, having a positive competitiveness to other students and can interact well between friends. Therefore, teachers need to know the ability of students SDT after making the learning process. This research was conducted to improve the process of learning mathematics by knowing the ability of students SDT. The researcher gave the question form to 38 students and analyzed the ability of SDT. The Results of the study showed that the student SDT ability is still poor. Students were lack of confidence to solve math problems. In addition, the competitiveness of students was low that have made them looked lazy. This can be resolved by making learning more interesting for students so that it can increase the student SDT ability.

  11. An analysis of primary school students’ representational ability in mathematics based on gender perspective

    Science.gov (United States)

    Kowiyah; Mulyawati, I.

    2018-01-01

    Mathematic representation is one of the basic mathematic skills that allows students to communicate their mathematic ideas through visual realities such as pictures, tables, mathematic expressions and mathematic equities. The present research aims at: 1) analysing students’ mathematic representation ability in solving mathematic problems and 2) examining the difference of students’ mathematic ability based on their gender. A total of sixty primary school students participated in this study comprising of thirty males and thirty females. Data required in this study were collected through mathematic representation tests, interviews and test evaluation rubric. Findings of this study showed that students’ mathematic representation of visual realities (image and tables) was reported higher at 62.3% than at in the form of description (or statement) at 8.6%. From gender perspective, male students performed better than the females at action planning stage. The percentage of males was reported at 68% (the highest), 33% (medium) and 21.3% (the lowest) while the females were at 36% (the highest), 37.7% (medium) and 32.6% (the lowest).

  12. Research in progress in applied mathematics, numerical analysis, and computer science

    Science.gov (United States)

    1990-01-01

    Research conducted at the Institute in Science and Engineering in applied mathematics, numerical analysis, and computer science is summarized. The Institute conducts unclassified basic research in applied mathematics in order to extend and improve problem solving capabilities in science and engineering, particularly in aeronautics and space.

  13. Primary Trait Analysis to Assess a Learner-Centered, Upper-Level Mathematics Course

    Science.gov (United States)

    Alsardary, Salar; Pontiggia, Laura; Hamid, Mohammed; Blumberg, Phyllis

    2011-01-01

    This study presents a primary trait analysis of a learner-centered, discrete mathematics course based on student-to-student instruction. The authors developed a scoring rubric for the primary traits: conceptual knowledge, procedural knowledge, application of understanding, and mathematical communication skills. Eleven students took an exam…

  14. Mathematical tapas

    CERN Document Server

    Hiriart-Urruty, Jean-Baptiste

    This book contains a collection of exercises (called “tapas”) at undergraduate level, mainly from the fields of real analysis, calculus, matrices, convexity, and optimization. Most of the problems presented here are non-standard and some require broad knowledge of different mathematical subjects in order to be solved. The author provides some hints and (partial) answers and also puts these carefully chosen exercises into context, presents information on their origins, and comments on possible extensions. With stars marking the levels of difficulty, these tapas show or prove something interesting, challenge the reader to solve and learn, and may have surprising results. This first volume of Mathematical Tapas will appeal to mathematicians, motivated undergraduate students from science-based areas, and those generally interested in mathematics.

  15. Mathematical modelling methodologies in predictive food microbiology: a SWOT analysis.

    Science.gov (United States)

    Ferrer, Jordi; Prats, Clara; López, Daniel; Vives-Rego, Josep

    2009-08-31

    Predictive microbiology is the area of food microbiology that attempts to forecast the quantitative evolution of microbial populations over time. This is achieved to a great extent through models that include the mechanisms governing population dynamics. Traditionally, the models used in predictive microbiology are whole-system continuous models that describe population dynamics by means of equations applied to extensive or averaged variables of the whole system. Many existing models can be classified by specific criteria. We can distinguish between survival and growth models by seeing whether they tackle mortality or cell duplication. We can distinguish between empirical (phenomenological) models, which mathematically describe specific behaviour, and theoretical (mechanistic) models with a biological basis, which search for the underlying mechanisms driving already observed phenomena. We can also distinguish between primary, secondary and tertiary models, by examining their treatment of the effects of external factors and constraints on the microbial community. Recently, the use of spatially explicit Individual-based Models (IbMs) has spread through predictive microbiology, due to the current technological capacity of performing measurements on single individual cells and thanks to the consolidation of computational modelling. Spatially explicit IbMs are bottom-up approaches to microbial communities that build bridges between the description of micro-organisms at the cell level and macroscopic observations at the population level. They provide greater insight into the mesoscale phenomena that link unicellular and population levels. Every model is built in response to a particular question and with different aims. Even so, in this research we conducted a SWOT (Strength, Weaknesses, Opportunities and Threats) analysis of the different approaches (population continuous modelling and Individual-based Modelling), which we hope will be helpful for current and future

  16. International Conference on Recent Trends in Mathematical Analysis and its Applications 2014

    CERN Document Server

    Mohapatra, R; Singh, Uaday; Srivastava, H

    2015-01-01

    This book discusses recent developments in and the latest research on mathematics, statistics and their applications. All contributing authors are eminent academics, scientists, researchers and scholars in their respective fields, hailing from around the world. The book presents roughly 60 unpublished, high-quality and peer-reviewed research papers that cover a broad range of areas including approximation theory, harmonic analysis, operator theory, fixed-point theory, functional differential equations, dynamical and control systems, complex analysis, special functions, function spaces, summability theory, Fourier and wavelet analysis, and numerical analysis – all of which are topics of great interest to the research community – while further papers highlight important applications of mathematical analysis in science, engineering and related areas. This conference aims at bringing together experts and young researchers in mathematics from all over the world to discuss the latest advances in mathematical an...

  17. A mathematical analysis of multiple-target SELEX.

    Science.gov (United States)

    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

  18. Performance Analysis of Parallel Mathematical Subroutine library PARCEL

    International Nuclear Information System (INIS)

    Yamada, Susumu; Shimizu, Futoshi; Kobayashi, Kenichi; Kaburaki, Hideo; Kishida, Norio

    2000-01-01

    The parallel mathematical subroutine library PARCEL (Parallel Computing Elements) has been developed by Japan Atomic Energy Research Institute for easy use of typical parallelized mathematical codes in any application problems on distributed parallel computers. The PARCEL includes routines for linear equations, eigenvalue problems, pseudo-random number generation, and fast Fourier transforms. It is shown that the results of performance for linear equations routines exhibit good parallelization efficiency on vector, as well as scalar, parallel computers. A comparison of the efficiency results with the PETSc (Portable Extensible Tool kit for Scientific Computations) library has been reported. (author)

  19. Mathematical bridges

    CERN Document Server

    Andreescu, Titu; Tetiva, Marian

    2017-01-01

    Building bridges between classical results and contemporary nonstandard problems, Mathematical Bridges embraces important topics in analysis and algebra from a problem-solving perspective. Blending old and new techniques, tactics and strategies used in solving challenging mathematical problems, readers will discover numerous genuine mathematical gems throughout that will heighten their appreciation of the inherent beauty of mathematics. Most of the problems are original to the authors and are intertwined in a well-motivated exposition driven by representative examples. The book is structured to assist the reader in formulating and proving conjectures, as well as devising solutions to important mathematical problems by making connections between various concepts and ideas from different areas of mathematics. Instructors and educators teaching problem-solving courses or organizing mathematics clubs, as well as motivated mathematics students from high school juniors to college seniors, will find Mathematical Bri...

  20. Mathematical Analysis of a Model for Human Immunodeficiency ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: The objective of this paper is to present a mathematical model formulated to investigate the dynamics of human immunodeficiency virus (HIV). The disease free equilibrium of the model was found to be locally and globally asymptotically stable. The endemic equilibrium point exists and it was discovered that the ...

  1. Mathematical analysis of education tax in Nigerian private schools ...

    African Journals Online (AJOL)

    To overcome inadequate funding of public schools, the introduction of education tax has been suggested in literature. This paper analysed the effects of such tax on private schools using mathematical models, and highlighted the ways for achieving the smooth functioning of the system. Three case senerios were studied: ...

  2. Categorization and Analysis of Explanatory Writing in Mathematics

    Science.gov (United States)

    Craig, Tracy S.

    2011-01-01

    The aim of this article is to present a scheme for coding and categorizing students' written explanations of mathematical problem-solving activities. The scheme was used successfully within a study project carried out to determine whether student problem-solving behaviour could be positively affected by writing explanatory strategies to…

  3. Mathematical analysis of the normal anatomy of the aging fovea.

    Science.gov (United States)

    Nesmith, Brooke; Gupta, Akash; Strange, Taylor; Schaal, Yuval; Schaal, Shlomit

    2014-08-28

    To mathematically analyze anatomical changes that occur in the normal fovea during aging. A total of 2912 spectral-domain optical coherence tomography (SD-OCT) normal foveal scans were analyzed. Subjects were healthy individuals, aged 13 to 97 years, with visual acuity ≥20/40 and without evidence of foveal pathology. Using automated symbolic regression software Eureqa (version 0.98), foveal thickness maps of 390 eyes were analyzed using several measurements: parafoveal retinal thickness at 50 μm consecutive intervals, parafoveal maximum retinal thickness at two points lateral to central foveal depression, distance between two points of maximum retinal thickness, maximal foveal slope at two intervals lateral to central foveal depression, and central length of foveal depression. A unique mathematical equation representing the mathematical analog of foveal anatomy was derived for every decade, between 10 and 100 years. The mathematical regression function for normal fovea followed first order sine curve of level 10 complexity for the second decade of life. The mathematical regression function became more complex with normal aging, up to level 43 complexity (0.085 fit; P < 0.05). Young foveas had higher symmetry (0.92 ± 0.10) along midline, whereas aged foveas had significantly less symmetry (0.76 ± 0.27, P < 0.01) along midline and steeper maximal slopes (29 ± 32°, P < 0.01). Normal foveal anatomical configuration changes with age. Normal aged foveas are less symmetric along midline with steeper slopes. Differentiating between normal aging and pathologic changes using SD-OCT scans may allow early diagnosis, follow-up, and better management of the aging population. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  4. An analysis of teacher’s preparation in implementing 2013 revision edition curriculum on mathematics specialization learning

    Science.gov (United States)

    Susilo, T.; Suryawan, A.

    2018-05-01

    This study aimed to determine the pedagogical competence of teachers, the readiness of planning and implementation of learning related to the implementation 2013 revised edition curriculum on mathematics specialization learning for senior high schools Wonogiri. Informants in this study there are 6 high school mathematics teachers X and XI class who teach in the school district Wonogiri. Data were collected using questionnaire method, interview, observation and documentation. Qualitative data analysis is done interactively through 4 paths: data collection, data reduction, data display, drawing conclusion. The results showed that high school mathematics teacher class X and XI in school district of Wonogiri City. The results show that most high school mathematics teachers in grade X and XI are ready to implement the 2013 revised edition curriculum and a few have not been able to implement due to internal or external factors. High school math teachers at Wonogiri district who are ready to face the 2013 revised edition curriculum have applied 10 teacher pedagogic competency indicators according to Regulation of the national education ministry Number 16 Year 2007 in learning. The readiness and implementation of mathematics learning is in line with the demands of the 2013 revised edition curriculum. Based on the teachers who are not ready, data on issues that arise in the implementation of the 2013 revised edition curriculum. Especially the problems in learning, namely mismatch of Core Competence (KI) and Basic Competence (KD) in teacher manual, material disregard in student handbook and lack of examples of problems that exist in teacher manual.

  5. SOME ASPECTS OF THE USE OF MATHEMATICAL-STATISTICAL METHODS IN THE ANALYSIS OF SOCIO-HUMANISTIC TEXTS Humanities and social text, mathematics, method, statistics, probability

    Directory of Open Access Journals (Sweden)

    Zaira M Alieva

    2016-01-01

    Full Text Available The article analyzes the application of mathematical and statistical methods in the analysis of socio-humanistic texts. The essence of mathematical and statistical methods, presents examples of their use in the study of Humanities and social phenomena. Considers the key issues faced by the expert in the application of mathematical-statistical methods in socio-humanitarian sphere, including the availability of sustainable contrasting socio-humanitarian Sciences and mathematics; the complexity of the allocation of the object that is the bearer of the problem; having the use of a probabilistic approach. The conclusion according to the results of the study.

  6. Mathematical analysis of a model for zoonotic visceral leishmaniasis

    Directory of Open Access Journals (Sweden)

    Nafiu Hussaini

    2017-11-01

    Full Text Available Zoonotic visceral leishmaniasis (ZVL, caused by the protozoan parasite Leishmania infantum and transmitted to humans and reservoir hosts by female sandflies, is endemic in many parts of the world (notably in Africa, Asia and the Mediterranean. This study presents a new mathematical model for assessing the transmission dynamics of ZVL in human and non-human animal reservoir populations. The model undergoes the usual phenomenon of backward bifurcation exhibited by similar vector-borne disease transmission models. In the absence of such phenomenon (which is shown to arise due to the disease-induced mortality in the host populations, the nontrivial disease-free equilibrium of the model is shown to be globally-asymptotically stable when the associated reproduction number of the model is less than unity. Using case and demographic data relevant to ZVL dynamics in Arac̣atuba municipality of Brazil, it is shown, for the default case when systemic insecticide-based drugs are not used to treat infected reservoir hosts, that the associated reproduction number of the model (ℛ0 ranges from 0.3 to 1.4, with a mean of ℛ0=0.85. Furthermore, when the effect of such drug treatment is explicitly incorporated in the model (i.e., accounting for the additional larval and sandfly mortality, following feeding on the treated reservoirs, the range of ℛ0 decreases to ℛ0∈[0.1,0.6], with a mean of ℛ0=0.35 (this significantly increases the prospect of the effective control or elimination of the disease. Thus, ZVL transmission models (in communities where such treatment strategy is implemented that do not explicitly incorporate the effect of such treatment may be over-estimating the disease burden (as measured in terms of ℛ0 in the community. It is shown that ℛ0 is more sensitive to increases in sandfly lifespan than that of the animal reservoir (so, a strategy that focuses on reducing sandflies, rather than the animal reservoir (e.g., via culling, may be

  7. From virtual clustering analysis to self-consistent clustering analysis: a mathematical study

    Science.gov (United States)

    Tang, Shaoqiang; Zhang, Lei; Liu, Wing Kam

    2018-03-01

    In this paper, we propose a new homogenization algorithm, virtual clustering analysis (VCA), as well as provide a mathematical framework for the recently proposed self-consistent clustering analysis (SCA) (Liu et al. in Comput Methods Appl Mech Eng 306:319-341, 2016). In the mathematical theory, we clarify the key assumptions and ideas of VCA and SCA, and derive the continuous and discrete Lippmann-Schwinger equations. Based on a key postulation of "once response similarly, always response similarly", clustering is performed in an offline stage by machine learning techniques (k-means and SOM), and facilitates substantial reduction of computational complexity in an online predictive stage. The clear mathematical setup allows for the first time a convergence study of clustering refinement in one space dimension. Convergence is proved rigorously, and found to be of second order from numerical investigations. Furthermore, we propose to suitably enlarge the domain in VCA, such that the boundary terms may be neglected in the Lippmann-Schwinger equation, by virtue of the Saint-Venant's principle. In contrast, they were not obtained in the original SCA paper, and we discover these terms may well be responsible for the numerical dependency on the choice of reference material property. Since VCA enhances the accuracy by overcoming the modeling error, and reduce the numerical cost by avoiding an outer loop iteration for attaining the material property consistency in SCA, its efficiency is expected even higher than the recently proposed SCA algorithm.

  8. Experimental and Mathematical Analysis of Multilayer Insulation below 80 K

    CERN Document Server

    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.

  9. Advanced Analysis of Isobaric Heat Capacities by Mathematical Gnostics

    Czech Academy of Sciences Publication Activity Database

    Wagner, Zdeněk; Bendová, Magdalena; Rotrekl, Jan; Velíšek, Petr; Storch, Jan; Uchytil, Petr; Setničková, Kateřina; Řezníčková Čermáková, Jiřina

    2017-01-01

    Roč. 46, 9-10 (2017), s. 1836-1853 ISSN 0095-9782. [International Symposium on Solubility Phenomena and Related Equilibrium Processes. Geneva, 24.07.2016-29.07.2016] R&D Projects: GA MŠk LD14090 Institutional support: RVO:67985858 Keywords : isobaric heat capacity * ionic liquids * mathematical gnostics Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 1.342, year: 2016

  10. Analysis of the coupling efficiency of a tapered space receiver with a calculus mathematical model

    Science.gov (United States)

    Hu, Qinggui; Mu, Yining

    2018-03-01

    We establish a calculus mathematical model to study the coupling characteristics of tapered optical fibers in a space communications system, and obtained the coupling efficiency equation. Then, using MATLAB software, the solution was calculated. After this, the sample was produced by the mature flame-brush technique. The experiment was then performed, and the results were in accordance with the theoretical analysis. This shows that the theoretical analysis was correct and indicates that a tapered structure could improve its tolerance with misalignment. Project supported by The National Natural Science Foundation of China (grant no. 61275080); 2017 Jilin Province Science and Technology Development Plan-Science and Technology Innovation Fund for Small and Medium Enterprises (20170308029HJ); ‘thirteen five’ science and technology research project of the Department of Education of Jilin 2016 (16JK009).

  11. An error analysis in the early grades mathematics – a learning opportunity?

    Directory of Open Access Journals (Sweden)

    Roelien Herholdt

    2014-07-01

    Full Text Available Error analysis is the study of errors in learners’ work with a view to looking for possible explanations for these errors. It is a multifaceted activity involving analysis of correct, partially correct and incorrect processes and thinking about possible remediating strategies. This paper reports on such an analysis of learner tests. The tests were administered as part of the evaluation of an intervention project that aimed to teach mathematical problem solving skills to grade 1-4 learners. Quantitative error analysis was carried out using a coding sheet for each grade. A reliability coefficient was found for each test, as were item means and discrimination indexes for each item. The analysis provided some insight into the more common procedural and conceptual errors evidenced in the learners’ scripts. Findings showed similar difficulties across intervention and control schools and highlighted particular areas of difficulty. The authors argue that this analysis is an example of large-scale error analysis, but that the analysis method could be adopted by teachers of grades 1-4.

  12. Engineering Mathematical Analysis Method for Productivity Rate in Linear Arrangement Serial Structure Automated Flow Assembly Line

    Directory of Open Access Journals (Sweden)

    Tan Chan Sin

    2015-01-01

    Full Text Available Productivity rate (Q or production rate is one of the important indicator criteria for industrial engineer to improve the system and finish good output in production or assembly line. Mathematical and statistical analysis method is required to be applied for productivity rate in industry visual overviews of the failure factors and further improvement within the production line especially for automated flow line since it is complicated. Mathematical model of productivity rate in linear arrangement serial structure automated flow line with different failure rate and bottleneck machining time parameters becomes the basic model for this productivity analysis. This paper presents the engineering mathematical analysis method which is applied in an automotive company which possesses automated flow assembly line in final assembly line to produce motorcycle in Malaysia. DCAS engineering and mathematical analysis method that consists of four stages known as data collection, calculation and comparison, analysis, and sustainable improvement is used to analyze productivity in automated flow assembly line based on particular mathematical model. Variety of failure rate that causes loss of productivity and bottleneck machining time is shown specifically in mathematic figure and presents the sustainable solution for productivity improvement for this final assembly automated flow line.

  13. A mathematical model of the hypothalamo-pituitary-adrenocortical system and its stability analysis

    International Nuclear Information System (INIS)

    Savic, Danka; Jelic, Smiljana

    2005-01-01

    It is commonly assumed that the hypothalamo-pituitary-adrenocortical (HPA) axis generates oscillations, because a regular daily rhythm of its component hormones is observed. We offer another plausible explanation of the origin of its circadian oscillations: HPA just responds to an independent external pacemaker (from the suprachiazmatic nucleus, SCN). Five versions (with and without time delay) of a qualitative non-phenomenological mathematical model of the HPA axis as a feedback mechanism are constructed wherein all the terms in the equations are introduced according to the rules of chemical kinetics, i.e. are physicochemically interpretable. The dynamics of the HPA axis model was examined using linear stability analysis. The results show stability of this system, meaning that it does not generate diurnal oscillations. Computer simulation based on this model shows oscillations that are system's response to an external pulsing activator (SCN) implying that the observed time-periodic pattern does not have to be an intrinsic property of the HPA axis

  14. Variational analysis and aerospace engineering mathematical challenges for the aerospace of the future

    CERN Document Server

    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.

  15. Mathematical analysis of partial differential equations modeling electrostatic MEMS

    CERN Document Server

    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

  16. Gender differences in mathematics achievement in Beijing: A meta-analysis.

    Science.gov (United States)

    Li, Meijuan; Zhang, Yongmei; Liu, Hongyun; Hao, Yi

    2017-12-19

    The topic of gender differences in mathematical performance has received considerable attention in the fields of education, sociology, economics and psychology. We analysed gender differences based on data from the Beijing Assessment of Educational Quality in China. A large data set of Grade 5 and Grade 8 students who took the mathematical test from 2008 to 2013 (n = 73,318) were analysed. Meta-analysis was used in this research. The findings were as follows. (1) No gender differences in mathematical achievement exist among students in Grade 5, relatively small gender differences exist in Grade 8, females scored higher than males, and variance of male students is larger than that of females in both Grade 5 and Grade 8. (2) Except for statistics and probability, gender differences in other domains in Grade 8 are significantly higher than those in Grade 5, and female students outperform males. (3) The ratio of students of both gender in Grade 5 and Grade 8 at the 95-100% percentile level shows no significant differences. However, the ratio of male students is significantly higher than that of females at the 0-5% percentile level. (4) In Grade 5, the extent to which females outperformed males in low SES group is larger than that in higher SES groups, and in Grade 8, the magnitude of gender differences in urban schools is smaller than that in rural schools. There is a small gender difference among the 8th graders, with the male disadvantage at the bottom of the distribution. And gender differences also vary across school locations. © 2017 The British Psychological Society.

  17. An Analysis of Mathematics Interventions: Increased Time-on-Task Compared with Computer-Assisted Mathematics Instruction

    Science.gov (United States)

    Calhoun, James M., Jr.

    2011-01-01

    Student achievement is not progressing on mathematics as measured by state, national, and international assessments. Much of the research points to mathematics curriculum and instruction as the root cause of student failure to achieve at levels comparable to other nations. Since mathematics is regarded as a gate keeper to many educational…

  18. On the Formal-Logical Analysis of the Foundations of Mathematics Applied to Problems in Physics

    Science.gov (United States)

    Kalanov, Temur Z.

    2016-03-01

    Analysis of the foundations of mathematics applied to problems in physics was proposed. The unity of formal logic and of rational dialectics is methodological basis of the analysis. It is shown that critical analysis of the concept of mathematical quantity - central concept of mathematics - leads to the following conclusion: (1) The concept of ``mathematical quantity'' is the result of the following mental operations: (a) abstraction of the ``quantitative determinacy of physical quantity'' from the ``physical quantity'' at that the ``quantitative determinacy of physical quantity'' is an independent object of thought; (b) abstraction of the ``amount (i.e., abstract number)'' from the ``quantitative determinacy of physical quantity'' at that the ``amount (i.e., abstract number)'' is an independent object of thought. In this case, unnamed, abstract numbers are the only sign of the ``mathematical quantity''. This sign is not an essential sign of the material objects. (2) The concept of mathematical quantity is meaningless, erroneous, and inadmissible concept in science because it represents the following formal-logical and dialectical-materialistic error: negation of the existence of the essential sign of the concept (i.e., negation of the existence of the essence of the concept) and negation of the existence of measure of material object.

  19. (Non-)symbolic magnitude processing in children with mathematical difficulties: A meta-analysis.

    Science.gov (United States)

    Schwenk, Christin; Sasanguie, Delphine; Kuhn, Jörg-Tobias; Kempe, Sophia; Doebler, Philipp; Holling, Heinz

    2017-05-01

    Symbolic and non-symbolic magnitude representations, measured by digit or dot comparison tasks, are assumed to underlie the development of arithmetic skills. The comparison distance effect (CDE) has been suggested as a hallmark of the preciseness of mental magnitude representations. It implies that two magnitudes are harder to discriminate when the numerical distance between them is small, and may therefore differ in children with mathematical difficulties (MD), i.e. low mathematical achievement or dyscalculia. However, empirical findings on the CDE in children with MD are heterogeneous, and only few studies assess both symbolic and non-symbolic skills. This meta-analysis therefore integrates 44 symbolic and 48 non-symbolic response time (RT) outcomes reported in nineteen studies (N=1630 subjects, aged 6-14 years). Independent of age, children with MD show significantly longer mean RTs than typically achieving controls, particularly on symbolic (Hedges' g=0.75; 95% CI [0.51; 0.99]), but to a significantly lower extent also on non-symbolic (g=0.24; 95% CI [0.13; 0.36]) tasks. However, no group differences were found for the CDE. Extending recent work, these meta-analytical findings on children with MD corroborate the diagnostic importance of magnitude comparison speed in symbolic tasks. By contrast, the validity of CDE measures in assessing MD is questioned. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. An Analysis on Eight Grade Mathematics Textbook of New Indonesian Curriculum (K-13 Based on Pisa’s Framework

    Directory of Open Access Journals (Sweden)

    Sarlita Murdaningsih

    2016-01-01

    Full Text Available This study aims to analyze and describe the mathematics problems in the eighth grade mathematics textbook of new Indonesian curriculum (K-13 based on The Programme for International Student Assesment (PISA frameworks. The object of this study was the the revised version textbooks of the eighth grade mathematics student’s book published by The Ministry of Education and Culture (Kemendikbud in 2014. The framework of the analysis in this study was the PISA components consisting of process, content, and context with its categories. The research method was descriptive quantitative. The data was collected by observing the contents of the textbook and interviewing the students and the teachers in SMP Negeri 2 Rembang. The analysis showed that the contents of the textbook were in accordance to the PISA components. The result also indicated that in both semester of the students’ book, the problems involving the process of employing mathematical concepts, facts, procedures, and reasoning were more dominant than others. Moreover, in the contexts, the problems were dominated by the personal context. Furthermore, the first semester students’ books were dominated by the change and relationships contents while the second semester books were dominated by the space and shape contents.

  1. Mathematical Methods for Engineers and Scientists 2 Vector Analysis, Ordinary Differential Equations and Laplace Transforms

    CERN Document Server

    Tang, Kwong-Tin

    2007-01-01

    Pedagogical insights gained through 30 years of teaching applied mathematics led the author to write this set of student-oriented books. Topics such as complex analysis, matrix theory, vector and tensor analysis, Fourier analysis, integral transforms, ordinary and partial differential equations are presented in a discursive style that is readable and easy to follow. Numerous clearly stated, completely worked out examples together with carefully selected problem sets with answers are used to enhance students' understanding and manipulative skill. The goal is to make students comfortable and confident in using advanced mathematical tools in junior, senior, and beginning graduate courses.

  2. Mathematical Methods for Engineers and Scientists 3 Fourier Analysis, Partial Differential Equations and Variational Methods

    CERN Document Server

    Tang, Kwong-Tin

    2007-01-01

    Pedagogical insights gained through 30 years of teaching applied mathematics led the author to write this set of student oriented books. Topics such as complex analysis, matrix theory, vector and tensor analysis, Fourier analysis, integral transforms, ordinary and partial differential equations are presented in a discursive style that is readable and easy to follow. Numerous clearly stated, completely worked out examples together with carefully selected problem sets with answers are used to enhance students' understanding and manipulative skill. The goal is to make students comfortable and confident in using advanced mathematical tools in junior, senior, and beginning graduate courses.

  3. Mathematical adventures in performance analysis from storage systems, through airplane boarding, to express line queues

    CERN Document Server

    Bachmat, Eitan

    2014-01-01

    This monograph describes problems in the field of performance analysis, primarily the study of storage systems and the diverse mathematical techniques that are required for solving such problems. Topics covered include best practices for scheduling I/O requests to a disk drive, how this problem is related to airplane boarding, and how both problems can be modeled using space-time geometry. The author also explains how Riemann's proof of the analytic continuation and functional equation of the Riemann zeta function can be used to analyze express-line queues in a minimarket. Overall, the book reveals the surprising applicability of abstract mathematical ideas that are not usually associated with applied topics. Advanced undergraduate students or graduate students with an interest in the applications of mathematics will find this book a useful resource. It will also be of interest to professional mathematicians who want exposure to the surprising ways that theoretical mathematics may be applied to engineering pr...

  4. THE METHODICAL ASPECTS OF THE ALGEBRA AND THE MATHEMATICAL ANALYSIS STUDY USING THE SAGEMATH CLOUD

    Directory of Open Access Journals (Sweden)

    M. Popel

    2014-06-01

    Full Text Available The quality of mathematics education depends largely on the quality of education in general. The main idea may be summarized as follows: in order to educate the younger generation of people to be able to meet adequately the demands of the time, it is necessary to create conditions for the high-quality mathematics education. Improving the quality of mathematics education of pupils in secondary school is one of the most pressing problems. Contents of the school course of mathematics and its teaching method has always been the subject of undammed and sometimes stormy scientific debates. There are especially true methods of teaching algebra and the analisis in the high secondary school. Still in the study process the algebraic concepts and principles of analysis are given in such an abstract and generalized form that the student may has considerable difficulties to map these general abstract concepts to the certain concrete images, they are generalizations of. Improving education quality indicators can be achieved by using the appropriate computer technology. The article deals with the use of the cloud-oriented systems of computer mathematics (SCM. The prospects of development of the Web-SCM in terms of cloud-based learning environment are considered. The pedagogical features of the SageMath Cloud use as a tool for mathematics learning are revealed. The methodological aspects of algebra and elementary analysis teaching in a high profile school using the cloud-oriented the SCM SageMath Cloud are revealed.

  5. Analyzing Mathematics Beliefs of Pre-Service Teachers Using Confirmatory Factor Analysis

    Directory of Open Access Journals (Sweden)

    Mazlini Adnan

    2011-12-01

    Full Text Available Mathematics beliefs play an important role in enhancing the quality and the effectiveness of teaching and learning. This study analyzes the mathematics beliefs of 317 pre-service teachers from six Higher Education Institutions (HEIs (Government Public Universities who were randomly selected to participate in this study. Questionnaires consisting of twenty three items were given to the respondents during the data collection process. The validation of the items was done by using confirmatory factor analysis (CFA. In order to obtain a model fit for the measurement model of mathematics beliefs, several fit index tests such as CMINDF, GFI, AGFI, IFI, NFI, CFI, TLI and RMSEA were used. Constructivist beliefs and traditional beliefs were identified as the contributing factors in the model. The analysis also revealed that mathematics beliefs consist of structures of two hidden variables. The correlation between the two variables (constructivist beliefs and traditional beliefs is at a moderate level. Hence, pre-service teachers should be able to recognize their type of mathematics beliefs in order to become effective mathematics teachers.

  6. A Mathematical Analysis of Air Traffic Priority Rules

    Science.gov (United States)

    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.

  7. Bifurcation analysis of a delayed mathematical model for tumor growth

    International Nuclear Information System (INIS)

    Khajanchi, Subhas

    2015-01-01

    In this study, we present a modified mathematical model of tumor growth by introducing discrete time delay in interaction terms. The model describes the interaction between tumor cells, healthy tissue cells (host cells) and immune effector cells. The goal of this study is to obtain a better compatibility with reality for which we introduced the discrete time delay in the interaction between tumor cells and host cells. We investigate the local stability of the non-negative equilibria and the existence of Hopf-bifurcation by considering the discrete time delay as a bifurcation parameter. We estimate the length of delay to preserve the stability of bifurcating periodic solutions, which gives an idea about the mode of action for controlling oscillations in the tumor growth. Numerical simulations of the model confirm the analytical findings

  8. Introduction to mathematical biology modeling, analysis, and simulations

    CERN Document Server

    Chou, Ching Shan

    2016-01-01

    This book is based on a one semester course that the authors have been teaching for several years, and includes two sets of case studies. The first includes chemostat models, predator-prey interaction, competition among species, the spread of infectious diseases, and oscillations arising from bifurcations. In developing these topics, readers will also be introduced to the basic theory of ordinary differential equations, and how to work with MATLAB without having any prior programming experience. The second set of case studies were adapted from recent and current research papers to the level of the students. Topics have been selected based on public health interest. This includes the risk of atherosclerosis associated with high cholesterol levels, cancer and immune interactions, cancer therapy, and tuberculosis. Readers will experience how mathematical models and their numerical simulations can provide explanations that guide biological and biomedical research. Considered to be the undergraduate companion to t...

  9. Mathematical and numerical analysis of PN models for photons transport problems

    International Nuclear Information System (INIS)

    Valentin, Xavier

    2015-01-01

    Computational costs for direct numerical simulations of photon transport problems are very high in terms of CPU time and memory. One way to tackle this issue is to develop reduced models that a cheaper to solve numerically. There exists number of these models: moments models, discrete ordinates models (S N ), diffusion-like models... In this thesis, we focus on P N models in which the transport operator is approached by mean of a truncated development on the spherical harmonics basis. These models are arbitrary accurate in the angular dimension and are rotationally invariants (in multiple space dimensions). The latter point is fundamental when one wants to simulate inertial confinement fusion (ICF) experiments where the spherical symmetry plays an important part in the accuracy of the numerical solutions. We study the mathematical structure of the PN models and construct a new numerical method in the special case of a one dimensional space dimension with spherical symmetry photon transport problems. We first focus on a linear transport problem in the vacuum. Even in this simple case, it appears in the P N equations geometrical source terms that are stiff in the neighborhood of r = 0 and thus hard to discretize. Existing numerical methods are not satisfactory for multiple reasons: (1) inaccuracy in the neighborhood of r = 0 ('flux-dip'), (2) do not capture steady states (well-balanced scheme), (3) no stability proof. Following recent works, we develop a new well-balanced scheme for which we show the L 2 stability. We then extend the scheme for photon transport problems within a no moving media, the linear Boltzmann equation, and interest ourselves on its behavior in the diffusion limit (asymptotic-preserving property). In a second part, we consider radiation hydrodynamics problems. Since modelization of these problems is still under discussion in the literature, we compare a set of existing models by mean of mathematical analysis and establish a hierarchy

  10. Using Citation Analysis Methods to Assess the Influence of Science, Technology, Engineering, and Mathematics Education Evaluations

    Science.gov (United States)

    Greenseid, Lija O.; Lawrenz, Frances

    2011-01-01

    This study explores the use of citation analysis methods to assess the influence of program evaluations conducted within the area of science, technology, engineering, and mathematics (STEM) education. Citation analysis is widely used within scientific research communities to measure the relative influence of scientific research enterprises and/or…

  11. Discrete Mathematics

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2011-01-01

    The objectives of Discrete Mathematics (IDISM2) are: The introduction of the mathematics needed for analysis, design and verification of discrete systems, including the application within programming languages for computer systems. Having passed the IDISM2 course, the student will be able...... to accomplish the following: -Understand and apply formal representations in discrete mathematics. -Understand and apply formal representations in problems within discrete mathematics. -Understand methods for solving problems in discrete mathematics. -Apply methods for solving problems in discrete mathematics......; construct a finite state machine for a given application. Apply these concepts to new problems. The teaching in Discrete Mathematics is a combination of sessions with lectures and students solving problems, either manually or by using Matlab. Furthermore a selection of projects must be solved and handed...

  12. Research Progress in Mathematical Analysis of Map Projection by Computer Algebra

    Directory of Open Access Journals (Sweden)

    BIAN Shaofeng

    2017-10-01

    Full Text Available Map projection is an important component of modern cartography, and involves many fussy mathematical analysis processes, such as the power series expansions of elliptical functions, differential of complex and implicit functions, elliptical integral and the operation of complex numbers. The derivation of these problems by hand not only consumes much time and energy but also makes mistake easily, and sometimes can not be realized at all because of the impossible complexity. The research achievements in mathematical analysis of map projection by computer algebra are systematically reviewed in five aspects, i.e., the symbolic expressions of forward and inverse solution of ellipsoidal latitudes, the direct transformations between map projections with different distortion properties, expressions of Gauss projection by complex function, mathematical analysis of oblique Mercator projection, polar chart projection with its transformation. Main problems that need to be further solved in this research field are analyzed. It will be helpful to promote the development of map projection.

  13. Bifurcation Analysis of an Existing Mathematical Model Reveals Novel Treatment Strategies and Suggests Potential Cure for Type 1 Diabetes

    DEFF Research Database (Denmark)

    Nielsen, Kenneth Hagde Mandrup; Ottesen, Johnny T.; Pociot, Flemming

    2014-01-01

    Type 1 diabetes is a disease with serious personal and socioeconomic consequences that has attracted the attention of modellers recently. But as models of this disease tend to be complicated, there has been only limited mathematical analysis to date. Here we address this problem by providing...... a bifurcation analysis of a previously published mathematical model for the early stages of type 1 diabetes in diabetes-prone NOD mice, which is based on the data available in the literature. We also show positivity and the existence of a family of attracting trapping regions in the positive 5D cone, converging...... or activated macrophages, increasing the phagocytic ability of resting and activated macrophages simultaneously and lastly, adding additional macrophages to the site of inflammation. The latter seems counter-intuitive at first glance, but nevertheless it appears to be the most promising, as evidenced by recent...

  14. The physical and mathematical model of dynamic economic analysis and assessment for NPP

    International Nuclear Information System (INIS)

    Xu Jiming

    1992-01-01

    A set physical and mathematical model of dynamic economic analysis referring to international general sub-item and account of investment and constant money levelized model and combining current economic analysis method in China for nuclear power plant was established. The model can be used in economic analysis not only for nuclear power plant but also for coal-fired power plant and can satisfy demand of doing economic analysis and assessment for nuclear power plant and conventional power plant

  15. The Education of Mathematics

    Directory of Open Access Journals (Sweden)

    Abu Darda

    2016-01-01

    Full Text Available The objective of mathematics education is not only preparingmathematicians but making well-informed citizens. This is a broad generalterms for objective of the teaching of mathematics. And, this might beimplemented as “accurate thorough knowledge” or “original logicalthinking”. So, teaching mathematics is not the conversation andtransmission of mathematical knowledge, but on the aim of preparing wellinformedcitizens trained in independent, critical thinking.By the mathematics, sciences become simple, clearer, and easier to bedeveloped. The mathematics is often applied for solving any problem ofother field of sciences, either in the physics such as astronomy, chemistry,technique; or social sciences such as economy, demography, and assurance.Those all need an analysis reading ability.Mathematical skill, therefore, relates strongly with the analysisreading ability in the human intellectual structure. This study is about therelationship between them. And, result of the study shows us as below:Both Mathematical skill and analysis reading ability possess the “high type”of thinking operation. Both also involve the same content of the abstractintelligent, i.e. symbolic and semantic contents. Last but not least, both alsouse the same product of thinking, i.e. units, classes, relations, and systems.Both can be transformed and have an implication.

  16. Technological pedagogical content knowledge in South African mathematics classrooms: A secondary analysis of SITES 2006 data

    Directory of Open Access Journals (Sweden)

    Verona Leendertz

    2013-12-01

    Full Text Available This article reports on a secondary data analysis conducted on the South African mathematics teachers’ dataset of the Second Information Technology in Education Study (SITES 2006. The sample consisted of a stratified sample of 640 mathematics teachers from 504 randomly selected computer-using and non–computer-using schools that completed the SITES 2006 teachers’ questionnaire, which investigated their pedagogical use of Information Communication Technology (ICT. The purpose of the current investigation was to investigate the level of Technological Pedagogical Content Knowledge (TPACK of mathematics teachers, and how TPACK attributes contribute towards more effective Grade 8 mathematics teaching in South African schools, using the TPACK conceptual framework. The findings are presented according to the three clusters identified through the association between the main variables of the TPACK model and other variables on the SITES 2006 teachers’ questionnaire: (1 impact of ICT use, (2 teacher practices and (3 barriers. A Cramér V of between 0.3 and 0.4 was considered to signal a medium effect that tended towards practically significant association, and a Cramér V of 0.4 or larger was considered to signal a large effect with practically significant association. The results indicate that the TPACK of mathematics teachers contributes towards more effective Grade 8 mathematics teaching in South African schools.

  17. Proteome Analysis of the Plant Pathogenic Fungus Monilinia laxa Showing Host Specificity

    Directory of Open Access Journals (Sweden)

    Olja Bregar

    2012-01-01

    Full Text Available Brown rot fungus Monilinia laxa (Aderh. & Ruhl. Honey is an important plant pathogen in stone and pome fruits in Europe. We applied a proteomic approach in a study of M. laxa isolates obtained from apples and apricots in order to show the host specifity of the isolates and to analyse differentially expressed proteins in terms of host specifity, fungal pathogenicity and identification of candidate proteins for diagnostic marker development. Extracted mycelium proteins were separated by 2-D electrophoresis (2-DE and visualized by Coomassie staining in a non-linear pH range of 3–11 and Mr of 14–116 kDa. We set up a 2-DE reference map of M. laxa, resolving up to 800 protein spots, and used it for image analysis. The average technical coefficient of variance (13 % demonstrated a high reproducibility of protein extraction and 2-D polyacrylamide gel electrophoresis (2-DE PAGE, and the average biological coefficient of variance (23 % enabled differential proteomic analysis of the isolates. Multivariate statistical analysis (principal component analysis discriminated isolates from two different hosts, providing new data that support the existence of a M. laxa specialized form f. sp. mali, which infects only apples. A total of 50 differentially expressed proteins were further analyzed by LC-MS/MS, yielding 41 positive identifications. The identified mycelial proteins were functionally classified into 6 groups: amino acid and protein metabolism, energy production, carbohydrate metabolism, stress response, fatty acid metabolism and other proteins. Some proteins expressed only in apple isolates have been described as virulence factors in other fungi. The acetolactate synthase was almost 11-fold more abundant in apple-specific isolates than in apricot isolates and it might be implicated in M. laxa host specificity. Ten proteins identified only in apple isolates are potential candidates for the development of M. laxa host-specific diagnostic markers.

  18. [Comparative analysis of the efficacy of a playful-narrative program to teach mathematics at pre-school level].

    Science.gov (United States)

    Gil Llario, M D; Vicent Catalá, Consuelo

    2009-02-01

    Comparative analysis of the efficacy of a playful-narrative program to teach mathematics at pre-school level. In this paper, the effectiveness of a programme comprising several components that are meant to consolidate mathematical concepts and abilities at the pre-school level is analyzed. The instructional methodology of this programme is compared to other methodologies. One-hundred 5-6 year-old children made up the sample that was distributed in the following conditions: (1) traditional methodology; (2) methodology with perceptual and manipulative components, and (3) methodology with language and playful components. Mathematical competence was assessed with the Mathematical Criterial Pre-school Test and the subtest of quantitative-numeric concepts of BADyG. Participants were evaluated before and after the academic course during which they followed one of these methodologies. The results show that the programme with language and playful components is more effective than the traditional methodology (p<.000) and also more effective than the perceptual and manipulative methodology (p<.000). Implications of the results for instructional practices are analyzed.

  19. Latent Class Analysis of Students' Mathematics Learning Strategies and the Relationship between Learning Strategy and Mathematical Literacy

    Science.gov (United States)

    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…

  20. Urine proteome analysis in Dent's disease shows high selective changes potentially involved in chronic renal damage.

    Science.gov (United States)

    Santucci, Laura; Candiano, Giovanni; Anglani, Franca; Bruschi, Maurizio; Tosetto, Enrica; Cremasco, Daniela; Murer, Luisa; D'Ambrosio, Chiara; Scaloni, Andrea; Petretto, Andrea; Caridi, Gianluca; Rossi, Roberta; Bonanni, Alice; Ghiggeri, Gian Marco

    2016-01-01

    Definition of the urinary protein composition would represent a potential tool for diagnosis in many clinical conditions. The use of new proteomic technologies allows detection of genetic and post-trasductional variants that increase sensitivity of the approach but complicates comparison within a heterogeneous patient population. Overall, this limits research of urinary biomarkers. Studying monogenic diseases are useful models to address this issue since genetic variability is reduced among first- and second-degree relatives of the same family. We applied this concept to Dent's disease, a monogenic condition characterised by low-molecular-weight proteinuria that is inherited following an X-linked trait. Results are presented here on a combined proteomic approach (LC-mass spectrometry, Western blot and zymograms for proteases and inhibitors) to characterise urine proteins in a large family (18 members, 6 hemizygous patients, 6 carrier females, and 6 normals) with Dent's diseases due to the 1070G>T mutation of the CLCN5. Gene ontology analysis on more than 1000 proteins showed that several clusters of proteins characterised urine of affected patients compared to carrier females and normal subjects: proteins involved in extracellular matrix remodelling were the major group. Specific analysis on metalloproteases and their inhibitors underscored unexpected mechanisms potentially involved in renal fibrosis. Studying with new-generation techniques for proteomic analysis of the members of a large family with Dent's disease sharing the same molecular defect allowed highly repetitive results that justify conclusions. Identification in urine of proteins actively involved in interstitial matrix remodelling poses the question of active anti-fibrotic drugs in Dent's patients. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. HIV-1 phylogenetic analysis shows HIV-1 transits through the meninges to brain and peripheral tissues.

    Science.gov (United States)

    Lamers, Susanna L; Gray, Rebecca R; Salemi, Marco; Huysentruyt, Leanne C; McGrath, Michael S

    2011-01-01

    Brain infection by the human immunodeficiency virus type 1 (HIV-1) has been investigated in many reports with a variety of conclusions concerning the time of entry and degree of viral compartmentalization. To address these diverse findings, we sequenced HIV-1 gp120 clones from a wide range of brain, peripheral and meningeal tissues from five patients who died from several HIV-1 associated disease pathologies. High-resolution phylogenetic analysis confirmed previous studies that showed a significant degree of compartmentalization in brain and peripheral tissue subpopulations. Some intermixing between the HIV-1 subpopulations was evident, especially in patients that died from pathologies other than HIV-associated dementia. Interestingly, the major tissue harboring virus from both the brain and peripheral tissues was the meninges. These results show that (1) HIV-1 is clearly capable of migrating out of the brain, (2) the meninges are the most likely primary transport tissues, and (3) infected brain macrophages comprise an important HIV reservoir during highly active antiretroviral therapy. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. Retrospective Analysis of Patient Presentations at the Sydney (Australia) Royal Easter Show from 2012 to 2014.

    Science.gov (United States)

    Crabtree, Nathan; Mo, Shirley; Ong, Leon; Jegathees, Thuvarahan; Wei, Daniel; Fahey, David; Liu, Jia Jenny

    2017-04-01

    Introduction Comprehensive studies on the relationship between patient demographics and subsequent treatment and disposition at a single mass-gathering event are lacking. The Sydney Royal Easter Show (SRES; Sydney Olympic Park, New South Wales, Australia) is an annual, 14-day, agricultural mass-gathering event occurring around the Easter weekend, attracting more than 800,000 patrons per year. In this study, patient records from the SRES were analyzed to examine relationships between weather, crowd size, day of week, and demographics on treatment and disposition. This information would help to predict factors affecting patient treatment and disposition to guide ongoing training of first responders and to evaluate the appropriateness of staffing skills mix at future events. Hypothesis Patient demographics, environmental factors, and attendance would influence the nature and severity of presentations at the SRES, which would influence staffing requirements. A retrospective analysis of 4,141 patient record forms was performed for patients who presented to St John Ambulance (Australian Capital Territory, Australia) at the SRES between 2012 and 2014 inclusive. Presentation type was classified using a previously published minimum data set. Data on weather and crowd size were obtained from the Australian Bureau of Meteorology (Melbourne, Victoria, Australia) and the SRES, respectively. Statistical analyses were performed using SPSS v22 (IBM; Armonk, New York USA). Between 2012 to 2014, over 2.5 million people attended the SRES with 4,141 patients treated onsite. As expected, the majority of presentations were injuries (49%) and illnesses (46%). Although patient demographics and presentation types did not change over time, the duration of treatment increased. A higher proportion of patients were discharged to hospital or home compared to the proportion of patients discharged back to the event. Patients from rural/regional locations (accounting for 15% of all patients) were

  3. Application of mathematical methods of analysis in selection of competing information technologies

    Science.gov (United States)

    Semenov, V. L.; Kadyshev, E. N.; Zakharova, A. N.; Patianova, A. O.; Dulina, G. S.

    2018-05-01

    The article discusses the use of qualimetry methods using the apparatus of mathematical analysis in the formation of the integral index that allows one to select the best option among competing information technology. The authors propose the use of affine space in the evaluation and selection of competing information technologies.

  4. Rethinking Critical Mathematics: A Comparative Analysis of Critical, Reform, and Traditional Geometry Instructional Texts

    Science.gov (United States)

    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…

  5. Digital Game-Based Learning for K-12 Mathematics Education: A Meta-Analysis

    Science.gov (United States)

    Byun, JaeHwan; Joung, Eunmi

    2018-01-01

    Digital games (e.g., video games or computer games) have been reported as an effective educational method that can improve students' motivation and performance in mathematics education. This meta-analysis study (a) investigates the current trend of digital game-based learning (DGBL) by reviewing the research studies on the use of DGBL for…

  6. Study on China’s Earthquake Prediction by Mathematical Analysis and its Application in Catastrophe Insurance

    Science.gov (United States)

    Jianjun, X.; Bingjie, Y.; Rongji, W.

    2018-03-01

    The purpose of this paper was to improve catastrophe insurance level. Firstly, earthquake predictions were carried out using mathematical analysis method. Secondly, the foreign catastrophe insurances’ policies and models were compared. Thirdly, the suggestions on catastrophe insurances to China were discussed. The further study should be paid more attention on the earthquake prediction by introducing big data.

  7. A Multilevel Analysis of Japanese Middle School Student and School Socioeconomic Status Influence on Mathematics Achievement

    Science.gov (United States)

    Takashiro, Naomi

    2017-01-01

    The author examined the simultaneous influence of Japanese middle school student and school socioeconomic status (SES) on student math achievement with two-level multilevel analysis models by utilizing the Trends in International Mathematics and Science Study (TIMSS) Japan data sets. The theoretical framework used in this study was…

  8. Enhancing Interdisciplinary Mathematics and Biology Education: A Microarray Data Analysis Course Bridging These Disciplines

    Science.gov (United States)

    Tra, Yolande V.; Evans, Irene M.

    2010-01-01

    "BIO2010" put forth the goal of improving the mathematical educational background of biology students. The analysis and interpretation of microarray high-dimensional data can be very challenging and is best done by a statistician and a biologist working and teaching in a collaborative manner. We set up such a collaboration and designed a course on…

  9. Mathematical Practice in Textbooks Analysis: Praxeological Reference Models, the Case of Proportion

    Science.gov (United States)

    Wijayanti, Dyana; Winsløw, Carl

    2017-01-01

    We present a new method in textbook analysis, based on so-called praxeological reference models focused on specific content at task level. This method implies that the mathematical contents of a textbook (or textbook part) is analyzed in terms of the tasks and techniques which are exposed to or demanded from readers; this can then be interpreted…

  10. The Effects of Problem Posing on Student Mathematical Learning: A Meta-Analysis

    Science.gov (United States)

    Rosli, Roslinda; Capraro, Mary Margaret; Capraro, Robert M.

    2014-01-01

    The purpose of the study was to meta-synthesize research findings on the effectiveness of problem posing and to investigate the factors that might affect the incorporation of problem posing in the teaching and learning of mathematics. The eligibility criteria for inclusion of literature in the meta-analysis was: published between 1989 and 2011,…

  11. Student Motivation and Learning in Mathematics and Science: A Cluster Analysis

    Science.gov (United States)

    Ng, Betsy L. L.; Liu, W. C.; Wang, John C. K.

    2016-01-01

    The present study focused on an in-depth understanding of student motivation and self-regulated learning in mathematics and science through cluster analysis. It examined the different learning profiles of motivational beliefs and self-regulatory strategies in relation to perceived teacher autonomy support, basic psychological needs (i.e. autonomy,…

  12. Mathematical and numerical analysis of systems of compressible hydrodynamics and photonics with polar coordinates

    International Nuclear Information System (INIS)

    Meltz, Bertrand

    2015-01-01

    This thesis deals with the mathematical and numerical analysis of the systems of compressible hydrodynamics and radiative transfer. More precisely, we study the derivation of numerical methods with 2D polar coordinates (one for the radius, one for the angle) where equations are discretized on regular polar grids. On one hand, these methods are well-suited for the simulation of flows with polar symmetries since they preserve these symmetries by construction. On the other hand, such coordinates systems introduce geometrical singularities as well as geometrical source terms which must be carefully treated. The first part of this document is devoted to the study of hydrodynamics equations, or Euler equations. We propose a new class of arbitrary high-order numerical schemes in both space and time and rely on directional splitting methods for the resolution of 2D equations. Each sub-system is solved using a Lagrange+Remap solver. We study the influence of the r=0 geometrical singularities of the cylindrical and spherical coordinates systems on the precision of the 2D numerical solutions. The second part of this document is devoted to the study of radiative transfer equations. In these equations, the unknowns depend on a large number of variables and a stiff source term is involved. The main difficulty consists in capturing the correct asymptotic behavior on coarse grids. We first construct a class of models where the radiative intensity is projected on a truncated spherical harmonics basis in order to lower the number of mathematical dimensions. Then we propose an Asymptotic Preserving scheme built in polar coordinates and we show that the scheme capture the correct diffusion limit in the radial direction as well as in the polar direction. (author) [fr

  13. Research in progress in applied mathematics, numerical analysis, fluid mechanics, and computer science

    Science.gov (United States)

    1994-01-01

    This report summarizes research conducted at the Institute for Computer Applications in Science and Engineering in applied mathematics, fluid mechanics, and computer science during the period October 1, 1993 through March 31, 1994. The major categories of the current ICASE research program are: (1) applied and numerical mathematics, including numerical analysis and algorithm development; (2) theoretical and computational research in fluid mechanics in selected areas of interest to LaRC, including acoustics and combustion; (3) experimental research in transition and turbulence and aerodynamics involving LaRC facilities and scientists; and (4) computer science.

  14. Dioscorea alata tuber proteome analysis shows over thirty dioscorin isoforms and novel tuber proteins.

    Science.gov (United States)

    Sharma, Shruti; Gupta, Ravi; Deswal, Renu

    2017-05-01

    In Dioscorea, dioscorin (31 kDa) is the major storage protein constituting 85% of the total tuber proteins. An integrated proteomic and biochemical approach was used to understand the physiological role of dioscorin in the two contrasting growth stages (germinating and mature tuber). HPLC analysis showed 3 fold reduction in mannitol and 12.88 and 1.24 fold increase in sucrose and maltose in the germinating tuber. A 1.8 and 3 fold increase in sucrose phosphate synthase and mannitol dehydrogenase activity respectively was observed in the germinating tuber while a 2 fold higher invertase probably lowers the sucrose accumulation in the mature tuber. SDS-PAGE and 2-D maps of the mature and germinating tubers confirmed depletion (more than 50%) of dioscorin on germination. Dioscorin was purified using ion exchange and gel filtration chromatography with 43.32 fold purification and 38.16 yield. Out of a trail of 35 spots at 31 kDa only 12 spots (identified as dioscorin isoforms) were present in the 2D gel of the purified fraction. To search for other tuber proteins besides dioscorin, the unbound fractions of DEAE column were analysed by 2DGE. DREB 1A, caffeic acid 3-O-methyltransferase and Rab-1 small GTP binding protein were identified perhaps for the first time in the Dioscorea proteome. The interactome analysis revealed these to be involved in oxidative stress, carotenoid synthesis and vesicular transport. This is perhaps the first attempt to identify tuber proteome (although limited) and to understand the physiological significance of these proteins. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  15. Genome-wide analysis of adolescent psychotic-like experiences shows genetic overlap with psychiatric disorders.

    Science.gov (United States)

    Pain, Oliver; Dudbridge, Frank; Cardno, Alastair G; Freeman, Daniel; Lu, Yi; Lundstrom, Sebastian; Lichtenstein, Paul; Ronald, Angelica

    2018-03-31

    This study aimed to test for overlap in genetic influences between psychotic-like experience traits shown by adolescents in the community, and clinically-recognized psychiatric disorders in adulthood, specifically schizophrenia, bipolar disorder, and major depression. The full spectra of psychotic-like experience domains, both in terms of their severity and type (positive, cognitive, and negative), were assessed using self- and parent-ratings in three European community samples aged 15-19 years (Final N incl. siblings = 6,297-10,098). A mega-genome-wide association study (mega-GWAS) for each psychotic-like experience domain was performed. Single nucleotide polymorphism (SNP)-heritability of each psychotic-like experience domain was estimated using genomic-relatedness-based restricted maximum-likelihood (GREML) and linkage disequilibrium- (LD-) score regression. Genetic overlap between specific psychotic-like experience domains and schizophrenia, bipolar disorder, and major depression was assessed using polygenic risk score (PRS) and LD-score regression. GREML returned SNP-heritability estimates of 3-9% for psychotic-like experience trait domains, with higher estimates for less skewed traits (Anhedonia, Cognitive Disorganization) than for more skewed traits (Paranoia and Hallucinations, Parent-rated Negative Symptoms). Mega-GWAS analysis identified one genome-wide significant association for Anhedonia within IDO2 but which did not replicate in an independent sample. PRS analysis revealed that the schizophrenia PRS significantly predicted all adolescent psychotic-like experience trait domains (Paranoia and Hallucinations only in non-zero scorers). The major depression PRS significantly predicted Anhedonia and Parent-rated Negative Symptoms in adolescence. Psychotic-like experiences during adolescence in the community show additive genetic effects and partly share genetic influences with clinically-recognized psychiatric disorders, specifically schizophrenia and

  16. A mathematical formulation for large strain analysis of geologic continua

    International Nuclear Information System (INIS)

    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

  17. Theoretical Mathematics

    Science.gov (United States)

    Stöltzner, Michael

    Answering to the double-faced influence of string theory on mathematical practice and rigour, the mathematical physicists Arthur Jaffe and Frank Quinn have contemplated the idea that there exists a `theoretical' mathematics (alongside `theoretical' physics) whose basic structures and results still require independent corroboration by mathematical proof. In this paper, I shall take the Jaffe-Quinn debate mainly as a problem of mathematical ontology and analyse it against the backdrop of two philosophical views that are appreciative towards informal mathematical development and conjectural results: Lakatos's methodology of proofs and refutations and John von Neumann's opportunistic reading of Hilbert's axiomatic method. The comparison of both approaches shows that mitigating Lakatos's falsificationism makes his insights about mathematical quasi-ontology more relevant to 20th century mathematics in which new structures are introduced by axiomatisation and not necessarily motivated by informal ancestors. The final section discusses the consequences of string theorists' claim to finality for the theory's mathematical make-up. I argue that ontological reductionism as advocated by particle physicists and the quest for mathematically deeper axioms do not necessarily lead to identical results.

  18. Mathematical modelling and linear stability analysis of laser fusion cutting

    International Nuclear Information System (INIS)

    Hermanns, Torsten; Schulz, Wolfgang; Vossen, Georg; Thombansen, Ulrich

    2016-01-01

    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.

  19. Mathematical modelling and linear stability analysis of laser fusion cutting

    Energy Technology Data Exchange (ETDEWEB)

    Hermanns, Torsten; Schulz, Wolfgang [RWTH Aachen University, Chair for Nonlinear Dynamics, Steinbachstr. 15, 52047 Aachen (Germany); Vossen, Georg [Niederrhein University of Applied Sciences, Chair for Applied Mathematics and Numerical Simulations, Reinarzstr.. 49, 47805 Krefeld (Germany); Thombansen, Ulrich [RWTH Aachen University, Chair for Laser Technology, Steinbachstr. 15, 52047 Aachen (Germany)

    2016-06-08

    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.

  20. Gut Transcriptome Analysis Shows Different Food Utilization Efficiency by the Grasshopper Oedaleous asiaticus (Orthoptera: Acrididae).

    Science.gov (United States)

    Huang, Xunbing; McNeill, Mark Richard; Ma, Jingchuan; Qin, Xinghu; Tu, Xiongbing; Cao, Guangchun; Wang, Guangjun; Nong, Xiangqun; Zhang, Zehua

    2017-08-01

    Oedaleus asiaticus B. Bienko is a persistent pest occurring in north Asian grasslands. We found that O. asiaticus feeding on Stipa krylovii Roshev. had higher approximate digestibility (AD), efficiency of conversion of ingested food (ECI), and efficiency of conversion of digested food (ECD), compared with cohorts feeding on Leymus chinensis (Trin.) Tzvel, Artemisia frigida Willd., or Cleistogenes squarrosa (Trin.) Keng. Although this indicated high food utilization efficiency for S. krylovii, the physiological processes and molecular mechanisms underlying these biological observations are not well understood. Transcriptome analysis was used to examine how gene expression levels in O. asiaticus gut are altered by feeding on the four plant species. Nymphs (fifth-instar female) that fed on S. krylovii had the largest variation in gene expression profiles, with a total of 88 genes significantly upregulated compared with those feeding on the other three plants, mainly including nutrition digestive genes of protein, carbohydrate, and lipid digestion. GO and KEGG enrichment also showed that feeding S. krylovii could upregulate the nutrition digestion-related molecular function, biological process, and pathways. These changes in transcripts levels indicate that the physiological processes of activating nutrition digestive enzymes and metabolism pathways can well explain the high food utilization of S. krylovii by O. asiaticus. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Factor analysis shows association between family activity environment and children's health behaviour.

    Science.gov (United States)

    Hendrie, Gilly A; Coveney, John; Cox, David N

    2011-12-01

    To characterise the family activity environment in a questionnaire format, assess the questionnaire's reliability and describe its predictive ability by examining the relationships between the family activity environment and children's health behaviours - physical activity, screen time and fruit and vegetable intake. This paper describes the creation of a tool, based on previously validated scales, adapted from the food domain. Data are from 106 children and their parents (Adelaide, South Australia). Factor analysis was used to characterise factors within the family activity environment. Pearson-Product Moment correlations between the family environment and child outcomes, controlling for demographic variation, were examined. Three factors described the family activity environment - parental activity involvement, opportunity for role modelling and parental support for physical activity - and explained 37.6% of the variance. Controlling for demographic factors, the scale was significantly correlated with children's health behaviour - physical activity (r=0.27), screen time (r=-0.24) and fruit and vegetable intake (r=0.34). The family activity environment questionnaire shows high internal consistency and moderate predictive ability. This study has built on previous research by taking a more comprehensive approach to measuring the family activity environment. This research suggests the family activity environment should be considered in family-based health promotion interventions. © 2011 The Authors. ANZJPH © 2011 Public Health Association of Australia.

  2. Mathematical analysis of the global dynamics of a power law model ...

    African Journals Online (AJOL)

    We analyze a mathematical power law model that describes HIV infection of CD4+ T cells. We report that the number of critical points depends on , where is a positive integer. We show that for any positive integer the infection – free equilibrium is asymptotically stable if the reproduction number R0 1.

  3. MATHEMATICAL ANALYSIS OF DENTAL ARCH OF CHILDREN IN NORMAL OCCLUSION: A LITERATURE REVIEW

    Directory of Open Access Journals (Sweden)

    M. Abu-Hussein DDS, MScD, MSc, DPD

    2012-03-01

    Full Text Available AIM. This paper is an attempt to compare and analyze the various mathematical models for defining the dental arch curvature of children in normal occlusion based upon a review of available literature. Background. While various studies have touched upon ways to cure or prevent dental diseases and upon surgical ways for teeth reconstitution to correct teeth anomalies during childhood, a substantial literature also exists, attempting to mathematically define the dental arch of children in normal occlusion. This paper reviews these dental studies and compares them analytically. Method. The paper compares the different mathematical approaches, highlights the basic assumptions behind each model, underscores the relevancy and applicability of the same, and also lists applicable mathematical formulae. Results. Each model has been found applicable to specific research conditions, as a universal mathematical model for describing the human dental arch still eludes satisfactory definition. The models necessarily need to include the features of the dental arch, such as shape, spacing between teeth and symmetry or asymmetry, but they also need substantial improvement. Conclusions. While the paper shows that the existing models are inadequate in properly defining the human dental arch, it also acknowledges that future research based on modern imaging techniques and computeraided simulation could well succeed in deriving an allinclusive definition for the human dental curve till now eluding the experts.

  4. Analysis of laser remote fusion cutting based on a mathematical model

    Energy Technology Data Exchange (ETDEWEB)

    Matti, R. S. [Department of Engineering Sciences and Mathematics, Luleå University of Technology, S-971 87 Luleå (Sweden); Department of Mechanical Engineering, College of Engineering, University of Mosul, Mosul (Iraq); Ilar, T.; Kaplan, A. F. H. [Department of Engineering Sciences and Mathematics, Luleå University of Technology, S-971 87 Luleå (Sweden)

    2013-12-21

    Laser remote fusion cutting is analyzed by the aid of a semi-analytical mathematical model of the processing front. By local calculation of the energy balance between the absorbed laser beam and the heat losses, the three-dimensional vaporization front can be calculated. Based on an empirical model for the melt flow field, from a mass balance, the melt film and the melting front can be derived, however only in a simplified manner and for quasi-steady state conditions. Front waviness and multiple reflections are not modelled. The model enables to compare the similarities, differences, and limits between laser remote fusion cutting, laser remote ablation cutting, and even laser keyhole welding. In contrast to the upper part of the vaporization front, the major part only slightly varies with respect to heat flux, laser power density, absorptivity, and angle of front inclination. Statistical analysis shows that for high cutting speed, the domains of high laser power density contribute much more to the formation of the front than for low speed. The semi-analytical modelling approach offers flexibility to simplify part of the process physics while, for example, sophisticated modelling of the complex focused fibre-guided laser beam is taken into account to enable deeper analysis of the beam interaction. Mechanisms like recast layer generation, absorptivity at a wavy processing front, and melt film formation are studied too.

  5. Analysis of laser remote fusion cutting based on a mathematical model

    International Nuclear Information System (INIS)

    Matti, R. S.; Ilar, T.; Kaplan, A. F. H.

    2013-01-01

    Laser remote fusion cutting is analyzed by the aid of a semi-analytical mathematical model of the processing front. By local calculation of the energy balance between the absorbed laser beam and the heat losses, the three-dimensional vaporization front can be calculated. Based on an empirical model for the melt flow field, from a mass balance, the melt film and the melting front can be derived, however only in a simplified manner and for quasi-steady state conditions. Front waviness and multiple reflections are not modelled. The model enables to compare the similarities, differences, and limits between laser remote fusion cutting, laser remote ablation cutting, and even laser keyhole welding. In contrast to the upper part of the vaporization front, the major part only slightly varies with respect to heat flux, laser power density, absorptivity, and angle of front inclination. Statistical analysis shows that for high cutting speed, the domains of high laser power density contribute much more to the formation of the front than for low speed. The semi-analytical modelling approach offers flexibility to simplify part of the process physics while, for example, sophisticated modelling of the complex focused fibre-guided laser beam is taken into account to enable deeper analysis of the beam interaction. Mechanisms like recast layer generation, absorptivity at a wavy processing front, and melt film formation are studied too

  6. Analysis of sample γ-spectrometry with mathematic simulating

    International Nuclear Information System (INIS)

    Guo Hongsheng; He Xijun; Peng Taiping; Yang Gaozhao; Wang Wenchuan; Feng Chun

    2005-01-01

    When a sample contains various energy γ-rays, its peak area records not only the events of optical-electronic effect but also the Compton scattering events of higher energy γ-rays. So the γ-ray intensity conducted by the peak area can not be gained. Using the anti-matrix method, the better results of analysis on the γ-spectrometry can be obtained. (authors)

  7. Some new mathematical methods for variational objective analysis

    Science.gov (United States)

    Wahba, Grace; Johnson, Donald R.

    1994-01-01

    Numerous results were obtained relevant to remote sensing, variational objective analysis, and data assimilation. A list of publications relevant in whole or in part is attached. The principal investigator gave many invited lectures, disseminating the results to the meteorological community as well as the statistical community. A list of invited lectures at meetings is attached, as well as a list of departmental colloquia at various universities and institutes.

  8. Railway bogie vibration analysis by mathematical simulation model and a scaled four-wheel railway bogie set

    Science.gov (United States)

    Visayataksin, Noppharat; Sooklamai, Manon

    2018-01-01

    The bogie is the part that connects and transfers all the load from the vehicle body onto the railway track; interestingly the interaction between wheels and rails is the critical point for derailment of the rail vehicles. However, observing or experimenting with real bogies on rail vehicles is impossible due to the operational rules and safety concerns. Therefore, this research aimed to develop a vibration analysis set for a four-wheel railway bogie by constructing a four-wheel bogie with scale of 1:4.5. The bogie structures, including wheels and axles, were made from an aluminium alloy, equipped with springs and dampers. The bogie was driven by an electric motor using 4 round wheels instead of 2 straight rails, with linear velocity between 0 to 11.22 m/s. The data collected from the vibration analysis set was compared to the mathematical simulation model to investigate the vibration behavior of the bogie, especially the hunting motion. The results showed that vibration behavior from a scaled four-wheel railway bogie set significantly agreed with the mathematical simulation model in terms of displacement and hunting frequency. The critical speed of the wheelset was found by executing the mathematical simulation model at 13 m/s.

  9. Mathematical statistics

    CERN Document Server

    Pestman, Wiebe R

    2009-01-01

    This textbook provides a broad and solid introduction to mathematical statistics, including the classical subjects hypothesis testing, normal regression analysis, and normal analysis of variance. In addition, non-parametric statistics and vectorial statistics are considered, as well as applications of stochastic analysis in modern statistics, e.g., Kolmogorov-Smirnov testing, smoothing techniques, robustness and density estimation. For students with some elementary mathematical background. With many exercises. Prerequisites from measure theory and linear algebra are presented.

  10. An epistemic framing analysis of upper level physics students' use of mathematics

    Science.gov (United States)

    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

  11. A mathematical model of the hypothalamo-pituitary-adrenocortical system and its stability analysis

    Energy Technology Data Exchange (ETDEWEB)

    Savic, Danka [Vinca Institute of Nuclear Sciences, Laboratory for Theoretical and Condensed Matter Physics, P.O. Box 522, Belgrade 11001 (Serbia and Montenegro)] e-mail: dankasav@eunet.yu; Jelic, Smiljana [Vinca Institute of Nuclear Sciences, Laboratory for Theoretical and Condensed Matter Physics, P.O. Box 522, Belgrade 11001 (Serbia and Montenegro)

    2005-10-01

    It is commonly assumed that the hypothalamo-pituitary-adrenocortical (HPA) axis generates oscillations, because a regular daily rhythm of its component hormones is observed. We offer another plausible explanation of the origin of its circadian oscillations: HPA just responds to an independent external pacemaker (from the suprachiazmatic nucleus, SCN). Five versions (with and without time delay) of a qualitative non-phenomenological mathematical model of the HPA axis as a feedback mechanism are constructed wherein all the terms in the equations are introduced according to the rules of chemical kinetics, i.e. are physicochemically interpretable. The dynamics of the HPA axis model was examined using linear stability analysis. The results show stability of this system, meaning that it does not generate diurnal oscillations. Computer simulation based on this model shows oscillations that are system's response to an external pulsing activator (SCN) implying that the observed time-periodic pattern does not have to be an intrinsic property of the HPA axis.

  12. Mathematical modelling and analysis for a three-tiered microbial food web in a chemostat

    Directory of Open Access Journals (Sweden)

    Miled El hajji

    2017-10-01

    Full Text Available In this article, we present a mathematical six-dimensional dynamical system involving a three-tiered microbial food web without maintenance. We give a qualitative analysis of the model, and an analysis of the local stability of equilibrium points. Under general assumptions of monotonicity, we prove the uniqueness and the local stability of the positive equilibrium point corresponding to the persistence of the three bacteria. Possibilities of periodic orbits are not excluded and asymptotic coexistence is satisfied.

  13. Mathematical properties of a semi-classical signal analysis method: Noisy signal case

    KAUST Repository

    Liu, Dayan

    2012-08-01

    Recently, a new signal analysis method based on a semi-classical approach has been proposed [1]. The main idea in this method is to interpret a signal as a potential of a Schrodinger operator and then to use the discrete spectrum of this operator to analyze the signal. In this paper, we are interested in a mathematical analysis of this method in discrete case considering noisy signals. © 2012 IEEE.

  14. Mathematical properties of a semi-classical signal analysis method: Noisy signal case

    KAUST Repository

    Liu, Dayan; Laleg-Kirati, Taous-Meriem

    2012-01-01

    Recently, a new signal analysis method based on a semi-classical approach has been proposed [1]. The main idea in this method is to interpret a signal as a potential of a Schrodinger operator and then to use the discrete spectrum of this operator to analyze the signal. In this paper, we are interested in a mathematical analysis of this method in discrete case considering noisy signals. © 2012 IEEE.

  15. Latent Cluster Analysis of Instructional Practices Reported by High- and Low-performing Mathematics Teachers in Four Countries

    OpenAIRE

    Cheng, Qiang; Hsu, Hsien-Yuan

    2017-01-01

    Using Trends in International Mathematics and Science Study (TIMSS) 2011 eighth-grade international dataset, this study explored the profiles of instructional practices reported by high- and low-performing mathematics teachers across the US, Finland, Korea, and Russia. Concepts of conceptual teaching and procedural teaching were used to frame the design of the current study. Latent cluster analysis was applied in the investigation of the profiles of mathematics teachers’ instructional practic...

  16. Descartes’s mathematical thought

    CERN Document Server

    Sasaki, Chikara

    2003-01-01

    Covering both the history of mathematics and of philosophy, Descartes's Mathematical Thought reconstructs the intellectual career of Descartes most comprehensively and originally in a global perspective including the history of early modern China and Japan. Especially, it shows what the concept of "mathesis universalis" meant before and during the period of Descartes and how it influenced the young Descartes. In fact, it was the most fundamental mathematical discipline during the seventeenth century, and for Descartes a key notion which may have led to his novel mathematics of algebraic analysis.

  17. Mathematical supply-chain modelling: Product analysis of cost and time

    International Nuclear Information System (INIS)

    Easters, D J

    2014-01-01

    Establishing a mathematical supply-chain model is a proposition that has received attention due to its inherent benefits of evolving global supply-chain efficiencies. This paper discusses the prevailing relationships found within apparel supply-chain environments, and contemplates the complex issues indicated for constituting a mathematical model. Principal results identified within the data suggest, that the multifarious nature of global supply-chain activities require a degree of simplification in order to fully dilate the necessary factors which affect, each sub-section of the chain. Subsequently, the research findings allowed the division of supply-chain components into sub-sections, which amassed a coherent method of product development activity. Concurrently, the supply-chain model was found to allow systematic mathematical formulae analysis, of cost and time, within the multiple contexts of each subsection encountered. The paper indicates the supply-chain model structure, the mathematics, and considers how product analysis of cost and time can improve the comprehension of product lifecycle management

  18. Mathematical supply-chain modelling: Product analysis of cost and time

    Science.gov (United States)

    Easters, D. J.

    2014-03-01

    Establishing a mathematical supply-chain model is a proposition that has received attention due to its inherent benefits of evolving global supply-chain efficiencies. This paper discusses the prevailing relationships found within apparel supply-chain environments, and contemplates the complex issues indicated for constituting a mathematical model. Principal results identified within the data suggest, that the multifarious nature of global supply-chain activities require a degree of simplification in order to fully dilate the necessary factors which affect, each sub-section of the chain. Subsequently, the research findings allowed the division of supply-chain components into sub-sections, which amassed a coherent method of product development activity. Concurrently, the supply-chain model was found to allow systematic mathematical formulae analysis, of cost and time, within the multiple contexts of each subsection encountered. The paper indicates the supply-chain model structure, the mathematics, and considers how product analysis of cost and time can improve the comprehension of product lifecycle management.

  19. Mathematical Analysis of a PDE System for Biological Network Formation

    KAUST Repository

    Haskovec, Jan

    2015-02-04

    Motivated by recent physics papers describing rules for natural network formation, we study an elliptic-parabolic system of partial differential equations proposed by Hu and Cai [13, 15]. The model describes the pressure field thanks to Darcy\\'s type equation and the dynamics of the conductance network under pressure force effects with a diffusion rate D >= 0 representing randomness in the material structure. We prove the existence of global weak solutions and of local mild solutions and study their long term behavior. It turns out that, by energy dissipation, steady states play a central role to understand the network formation capacity of the system. We show that for a large diffusion coefficient D, the zero steady state is stable, while network formation occurs for small values of D due to the instability of the zero steady state, and the borderline case D = 0 exhibits a large class of dynamically stable (in the linearized sense) steady states.

  20. Mathematical analysis of running performance and world running records.

    Science.gov (United States)

    Péronnet, F; Thibault, G

    1989-07-01

    The objective of this study was to develop an empirical model relating human running performance to some characteristics of metabolic energy-yielding processes using A, the capacity of anaerobic metabolism (J/kg); MAP, the maximal aerobic power (W/kg); and E, the reduction in peak aerobic power with the natural logarithm of race duration T, when T greater than TMAP = 420 s. Accordingly, the model developed describes the average power output PT (W/kg) sustained over any T as PT = [S/T(1 - e-T/k2)] + 1/T integral of T O [BMR + B(1 - e-t/k1)]dt where S = A and B = MAP - BMR (basal metabolic rate) when T less than TMAP; and S = A + [Af ln(T/TMAP)] and B = (MAP - BMR) + [E ln(T/TMAP)] when T greater than TMAP; k1 = 30 s and k2 = 20 s are time constants describing the kinetics of aerobic and anaerobic metabolism, respectively, at the beginning of exercise; f is a constant describing the reduction in the amount of energy provided from anaerobic metabolism with increasing T; and t is the time from the onset of the race. This model accurately estimates actual power outputs sustained over a wide range of events, e.g., average absolute error between actual and estimated T for men's 1987 world records from 60 m to the marathon = 0.73%. In addition, satisfactory estimations of the metabolic characteristics of world-class male runners were made as follows: A = 1,658 J/kg; MAP = 83.5 ml O2.kg-1.min-1; 83.5% MAP sustained over the marathon distance. Application of the model to analysis of the evolution of A, MAP, and E, and of the progression of men's and women's world records over the years, is presented.

  1. Mathematical Analysis of Replication by Cash Flow Matching

    Directory of Open Access Journals (Sweden)

    Jan Natolski

    2017-02-01

    Full Text Available The replicating portfolio approach is a well-established approach carried out by many life insurance companies within their Solvency II framework for the computation of risk capital. In this note,weelaborateononespecificformulationofareplicatingportfolioproblem. Incontrasttothetwo most popular replication approaches, it does not yield an analytic solution (if, at all, a solution exists andisunique. Further,althoughconvex,theobjectivefunctionseemstobenon-smooth,andhencea numericalsolutionmightthusbemuchmoredemandingthanforthetwomostpopularformulations. Especially for the second reason, this formulation did not (yet receive much attention in practical applications, in contrast to the other two formulations. In the following, we will demonstrate that the (potential non-smoothness can be avoided due to an equivalent reformulation as a linear second order cone program (SOCP. This allows for a numerical solution by efficient second order methods like interior point methods or similar. We also show that—under weak assumptions—existence and uniqueness of the optimal solution can be guaranteed. We additionally prove that—under a further similarly weak condition—the fair value of the replicating portfolio equals the fair value of liabilities. Based on these insights, we argue that this unloved stepmother child within the replication problem family indeed represents an equally good formulation for practical purposes.

  2. Discrete Mathematics

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2010-01-01

    The introduction of the mathematics needed for analysis, design and verification of discrete systems, including applications within programming languages for computer systems. Course sessions and project work. Semester: Spring 2010 Ectent: 5 ects Class size: 18......The introduction of the mathematics needed for analysis, design and verification of discrete systems, including applications within programming languages for computer systems. Course sessions and project work. Semester: Spring 2010 Ectent: 5 ects Class size: 18...

  3. Discrete Mathematics

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2010-01-01

    The introduction of the mathematics needed for analysis, design and verification of discrete systems, including applications within programming languages for computer systems. Course sessions and project work. Semester: Autumn 2010 Ectent: 5 ects Class size: 15......The introduction of the mathematics needed for analysis, design and verification of discrete systems, including applications within programming languages for computer systems. Course sessions and project work. Semester: Autumn 2010 Ectent: 5 ects Class size: 15...

  4. Structural analysis of online handwritten mathematical symbols based on support vector machines

    Science.gov (United States)

    Simistira, Foteini; Papavassiliou, Vassilis; Katsouros, Vassilis; Carayannis, George

    2013-01-01

    Mathematical expression recognition is still a very challenging task for the research community mainly because of the two-dimensional (2d) structure of mathematical expressions (MEs). In this paper, we present a novel approach for the structural analysis between two on-line handwritten mathematical symbols of a ME, based on spatial features of the symbols. We introduce six features to represent the spatial affinity of the symbols and compare two multi-class classification methods that employ support vector machines (SVMs): one based on the "one-against-one" technique and one based on the "one-against-all", in identifying the relation between a pair of symbols (i.e. subscript, numerator, etc). A dataset containing 1906 spatial relations derived from the Competition on Recognition of Online Handwritten Mathematical Expressions (CROHME) 2012 training dataset is constructed to evaluate the classifiers and compare them with the rule-based classifier of the ILSP-1 system participated in the contest. The experimental results give an overall mean error rate of 2.61% for the "one-against-one" SVM approach, 6.57% for the "one-against-all" SVM technique and 12.31% error rate for the ILSP-1 classifier.

  5. BIOMETRICAL ANALYSIS OF ARABIAN FOALS AND THEIR LATER SUCCESSES IN SHOWS AND ON RACE TRACK

    Directory of Open Access Journals (Sweden)

    M. PIESZKA

    2007-10-01

    Full Text Available Arabian horses are one of the most important products of Polish horse breeding.Many of them are International and World champions in shows; others are very wellknown as courageous race horses. To obtain such champions it is necessary to takeunder consideration many factors affecting the final results. The objective of thisstudy was to evaluate the effect of biometrical measurements of the foals at birthaccording to their future successes in shows and on racetrack. The study was carriedout on 143 horses winning in shows and in races. Body weight, height at withers,girth and canon circumferences taken at birth of these horses were analysed.Additionally coat colour was studied. All studied animals were divided into threegroups according to each measurement and the differences between such groupswere evaluated according points obtained for particular place at shows and place inraces. It was stated that horses heavier at birth and with higher girth circumferencegot more successes both at shows and on racetrack. Horses with higher height atwithers at birth were more successful in shows while animals with higher canoncircumference won oftener at race track. It was observed that the most courageousrace horses were bay while most champions were grey.

  6. Mathematical analysis of the 1D model and reconstruction schemes for magnetic particle imaging

    Science.gov (United States)

    Erb, W.; Weinmann, A.; Ahlborg, M.; Brandt, C.; Bringout, G.; Buzug, T. M.; Frikel, J.; Kaethner, C.; Knopp, T.; März, T.; Möddel, M.; Storath, M.; Weber, A.

    2018-05-01

    Magnetic particle imaging (MPI) is a promising new in vivo medical imaging modality in which distributions of super-paramagnetic nanoparticles are tracked based on their response in an applied magnetic field. In this paper we provide a mathematical analysis of the modeled MPI operator in the univariate situation. We provide a Hilbert space setup, in which the MPI operator is decomposed into simple building blocks and in which these building blocks are analyzed with respect to their mathematical properties. In turn, we obtain an analysis of the MPI forward operator and, in particular, of its ill-posedness properties. We further get that the singular values of the MPI core operator decrease exponentially. We complement our analytic results by some numerical studies which, in particular, suggest a rapid decay of the singular values of the MPI operator.

  7. Analysis of mathematical literacy ability based on goal orientation in model eliciting activities learning with murder strategy

    Science.gov (United States)

    Wijayanti, R.; Waluya, S. B.; Masrukan

    2018-03-01

    The purpose of this research are (1) to analyze the learning quality of MEAs with MURDER strategy, (2) to analyze students’ mathematical literacy ability based on goal orientation in MEAs learning with MURDER strategy. This research is a mixed method research of concurrent embedded type where qualitative method as the primary method. The data were obtained using the methods of scale, observation, test and interviews. The results showed that (1) MEAs Learning with MURDER strategy on students' mathematical literacy ability is qualified, (2) Students who have mastery goal characteristics are able to master the seven components of mathematical literacy process although there are still two components that the solution is less than the maximum. Students who have performance goal characteristics have not mastered the components of mathematical literacy process with the maximum, they are only able to master the ability of using mathematics tool and the other components of mathematical literacy process is quite good.

  8. VIPRE-01. a thermal-hydraulic analysis code for reactor cores. Volume 1. Mathematical modeling

    International Nuclear Information System (INIS)

    Stewart, C.W.; Cuta, J.M.; Koontz, A.S.; Kelly, J.M.; Basehore, K.L.; George, T.L.; Rowe, D.S.

    1983-04-01

    VIPRE (Versatile Internals and Component Program for Reactors; EPRI) has been developed for nuclear power utility thermal-hydraulic analysis applications. It is designed to help evaluate nuclear reactor core safety limits including minimum departure from nucleate boiling ratio (MDNBR), critical power ratio (CPR), fuel and clad temperatures, and coolant state in normal operation and assumed accident conditions. This volume (Volume 1: Mathematical Modeling) explains the major thermal hydraulic models and supporting correlations in detail

  9. A mathematical and numerical analysis of the Maxwell-Stefan diffusion equations

    OpenAIRE

    Boudin , Laurent; Grec , Bérénice; Salvarani , Francesco

    2012-01-01

    International audience; We consider the Maxwell-Stefan model of diffusion in a multicomponent gaseous mixture. After focusing on the main differences with the Fickian diffusion model, we study the equations governing a three-component gas mixture. We provide a qualitative and quantitative mathematical analysis of the model. The main properties of the standard explicit numerical scheme are also analyzed. We eventually include some numerical simulations pointing out the uphill diffusion phenome...

  10. Economic impact and market analysis of a special event: The Great New England Air Show

    Science.gov (United States)

    Rodney B. Warnick; David C. Bojanic; Atul Sheel; Apurv Mather; Deepak Ninan

    2010-01-01

    We conducted a post-event evaluation for the Great New England Air Show to assess its general economic impact and to refine economic estimates where possible. In addition to the standard economic impact variables, we examined travel distance, purchase decision involvement, event satisfaction, and frequency of attendance. Graphic mapping of event visitors' home ZIP...

  11. Radiographic analysis of odontogenic cysts showing displacement of the mandibular canal

    International Nuclear Information System (INIS)

    Cho, Bong Hae

    2003-01-01

    To assess the radiographic findings of odontogenic cysts showing displacement of the mandibular canal using computed tomographic (CT) and panoramic images. CT and panoramic images of 63 odontogenic cysts (27 dentigerous, 16 odontogenic keratocysts, and 20 radicular cysts) were analyzed to evaluate the following parameters: the dimension and shape of the cysts, and the effect of the cysts on the mandibular canal and cortical plates. Of the 63 cysts examined in the study, 35 (55.6%) showed inferior displacement of the mandibular canal and 46 (73.0%) showed perforation of the canal. There were statistically significant differenced between CT and panoramic images in depicting displacement and perforation of the mandibular canal. Cortical expansion was seen in 46 cases (73.0%) and cortical perforation in 23 cases (36.5%). The radicular cysts showed cortical expansion and perforation less frequently than the other cyst groups. Large cysts of mandible should be evaluated by multiplanar CT images in order to detect the mandibular canal and cortical bone involvement.

  12. Social network analysis shows direct evidence for social transmission of tool use in wild chimpanzees.

    Directory of Open Access Journals (Sweden)

    Catherine Hobaiter

    2014-09-01

    Full Text Available Social network analysis methods have made it possible to test whether novel behaviors in animals spread through individual or social learning. To date, however, social network analysis of wild populations has been limited to static models that cannot precisely reflect the dynamics of learning, for instance, the impact of multiple observations across time. Here, we present a novel dynamic version of network analysis that is capable of capturing temporal aspects of acquisition--that is, how successive observations by an individual influence its acquisition of the novel behavior. We apply this model to studying the spread of two novel tool-use variants, "moss-sponging" and "leaf-sponge re-use," in the Sonso chimpanzee community of Budongo Forest, Uganda. Chimpanzees are widely considered the most "cultural" of all animal species, with 39 behaviors suspected as socially acquired, most of them in the domain of tool-use. The cultural hypothesis is supported by experimental data from captive chimpanzees and a range of observational data. However, for wild groups, there is still no direct experimental evidence for social learning, nor has there been any direct observation of social diffusion of behavioral innovations. Here, we tested both a static and a dynamic network model and found strong evidence that diffusion patterns of moss-sponging, but not leaf-sponge re-use, were significantly better explained by social than individual learning. The most conservative estimate of social transmission accounted for 85% of observed events, with an estimated 15-fold increase in learning rate for each time a novice observed an informed individual moss-sponging. We conclude that group-specific behavioral variants in wild chimpanzees can be socially learned, adding to the evidence that this prerequisite for culture originated in a common ancestor of great apes and humans, long before the advent of modern humans.

  13. Social network analysis shows direct evidence for social transmission of tool use in wild chimpanzees.

    Science.gov (United States)

    Hobaiter, Catherine; Poisot, Timothée; Zuberbühler, Klaus; Hoppitt, William; Gruber, Thibaud

    2014-09-01

    Social network analysis methods have made it possible to test whether novel behaviors in animals spread through individual or social learning. To date, however, social network analysis of wild populations has been limited to static models that cannot precisely reflect the dynamics of learning, for instance, the impact of multiple observations across time. Here, we present a novel dynamic version of network analysis that is capable of capturing temporal aspects of acquisition--that is, how successive observations by an individual influence its acquisition of the novel behavior. We apply this model to studying the spread of two novel tool-use variants, "moss-sponging" and "leaf-sponge re-use," in the Sonso chimpanzee community of Budongo Forest, Uganda. Chimpanzees are widely considered the most "cultural" of all animal species, with 39 behaviors suspected as socially acquired, most of them in the domain of tool-use. The cultural hypothesis is supported by experimental data from captive chimpanzees and a range of observational data. However, for wild groups, there is still no direct experimental evidence for social learning, nor has there been any direct observation of social diffusion of behavioral innovations. Here, we tested both a static and a dynamic network model and found strong evidence that diffusion patterns of moss-sponging, but not leaf-sponge re-use, were significantly better explained by social than individual learning. The most conservative estimate of social transmission accounted for 85% of observed events, with an estimated 15-fold increase in learning rate for each time a novice observed an informed individual moss-sponging. We conclude that group-specific behavioral variants in wild chimpanzees can be socially learned, adding to the evidence that this prerequisite for culture originated in a common ancestor of great apes and humans, long before the advent of modern humans.

  14. Can Automated Facial Expression Analysis Show Differences Between Autism and Typical Functioning?

    Science.gov (United States)

    Borsos, Zsófia; Gyori, Miklos

    2017-01-01

    Exploratory analyses of emotional expressions using a commercially available facial expression recognition software are reported, from the context of a serious game for screening purposes. Our results are based on a comparative analysis of two matched groups of kindergarten-age children (high-functioning children with autism spectrum condition: n=13; typically developing children: n=13). Results indicate that this technology has the potential to identify autism-specific emotion expression features, and may play a role in affective diagnostic and assistive technologies.

  15. Analysis Critical Thinking Stage of Eighth Grade in PBL-Scaffolding Setting To Solve Mathematical Problems

    OpenAIRE

    Nur Aisyah Isti; Arief Agoestanto; Ary Woro Kurniasih

    2017-01-01

    The purpose of this research was described critical thinking stage of students grade VIII in setting PBL and scaffolding to solve mathematics problems. Critical thinking stage consists of clarification, assesment, inference, and strategy/tactics. The subject were teo students in the level of capacity to think critical (uncritical, less critical, quite critical, and critical). So that this research subject was 8 students in VIII A One State Junior High School of Temanggung. The result showed a...

  16. A micro-epidemiological analysis of febrile malaria in Coastal Kenya showing hotspots within hotspots.

    Science.gov (United States)

    Bejon, Philip; Williams, Thomas N; Nyundo, Christopher; Hay, Simon I; Benz, David; Gething, Peter W; Otiende, Mark; Peshu, Judy; Bashraheil, Mahfudh; Greenhouse, Bryan; Bousema, Teun; Bauni, Evasius; Marsh, Kevin; Smith, David L; Borrmann, Steffen

    2014-04-24

    Malaria transmission is spatially heterogeneous. This reduces the efficacy of control strategies, but focusing control strategies on clusters or 'hotspots' of transmission may be highly effective. Among 1500 homesteads in coastal Kenya we calculated (a) the fraction of febrile children with positive malaria smears per homestead, and (b) the mean age of children with malaria per homestead. These two measures were inversely correlated, indicating that children in homesteads at higher transmission acquire immunity more rapidly. This inverse correlation increased gradually with increasing spatial scale of analysis, and hotspots of febrile malaria were identified at every scale. We found hotspots within hotspots, down to the level of an individual homestead. Febrile malaria hotspots were temporally unstable, but 4 km radius hotspots could be targeted for 1 month following 1 month periods of surveillance.DOI: http://dx.doi.org/10.7554/eLife.02130.001. Copyright © 2014, Bejon et al.

  17. Analysis of allergen immunotherapy studies shows increased clinical efficacy in highly symptomatic patients

    DEFF Research Database (Denmark)

    Howarth, P; Malling, Hans-Jørgen; Molimard, M

    2011-01-01

    them. Thus, clinical studies of AIT can neither establish baseline symptom levels nor limit the enrolment of patients to those with the most severe symptoms. Allergen immunotherapy treatment effects are therefore diluted by patients with low symptoms for a particular pollen season. The objective...... tertiles). The difference observed in the average score in each tertile in active vs placebo-treated patients was assessed. This allowed an estimation of the efficacy that could be achieved in patients from sites where symptoms were high during the pollen season. Results:  An increased treatment effect...... of this analysis was to assess the effect possible to achieve with AIT in the groups of patients presenting the most severe allergic symptoms. Methods:  Study centres were grouped into tertiles categorized according to symptom severity scores observed in the placebo patients in each centre (low, middle and high...

  18. Commognitive analysis of undergraduate mathematics students' first encounter with the subgroup test

    Science.gov (United States)

    Ioannou, Marios

    2018-06-01

    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.

  19. Human evaluation in association to the mathematical analysis of arch forms: Two-dimensional study.

    Science.gov (United States)

    Zabidin, Nurwahidah; Mohamed, Alizae Marny; Zaharim, Azami; Marizan Nor, Murshida; Rosli, Tanti Irawati

    2018-03-01

    To evaluate the relationship between human evaluation of the dental-arch form, to complete a mathematical analysis via two different methods in quantifying the arch form, and to establish agreement with the fourth-order polynomial equation. This study included 64 sets of digitised maxilla and mandible dental casts obtained from a sample of dental arch with normal occlusion. For human evaluation, a convenient sample of orthodontic practitioners ranked the photo images of dental cast from the most tapered to the less tapered (square). In the mathematical analysis, dental arches were interpolated using the fourth-order polynomial equation with millimetric acetate paper and AutoCAD software. Finally, the relations between human evaluation and mathematical objective analyses were evaluated. Human evaluations were found to be generally in agreement, but only at the extremes of tapered and square arch forms; this indicated general human error and observer bias. The two methods used to plot the arch form were comparable. The use of fourth-order polynomial equation may be facilitative in obtaining a smooth curve, which can produce a template for individual arch that represents all potential tooth positions for the dental arch. Copyright © 2018 CEO. Published by Elsevier Masson SAS. All rights reserved.

  20. Mathematical modelling

    CERN Document Server

    2016-01-01

    This book provides a thorough introduction to the challenge of applying mathematics in real-world scenarios. Modelling tasks rarely involve well-defined categories, and they often require multidisciplinary input from mathematics, physics, computer sciences, or engineering. In keeping with this spirit of modelling, the book includes a wealth of cross-references between the chapters and frequently points to the real-world context. The book combines classical approaches to modelling with novel areas such as soft computing methods, inverse problems, and model uncertainty. Attention is also paid to the interaction between models, data and the use of mathematical software. The reader will find a broad selection of theoretical tools for practicing industrial mathematics, including the analysis of continuum models, probabilistic and discrete phenomena, and asymptotic and sensitivity analysis.

  1. Algorithmic mathematics

    CERN Document Server

    Hougardy, Stefan

    2016-01-01

    Algorithms play an increasingly important role in nearly all fields of mathematics. This book allows readers to develop basic mathematical abilities, in particular those concerning the design and analysis of algorithms as well as their implementation. It presents not only fundamental algorithms like the sieve of Eratosthenes, the Euclidean algorithm, sorting algorithms, algorithms on graphs, and Gaussian elimination, but also discusses elementary data structures, basic graph theory, and numerical questions. In addition, it provides an introduction to programming and demonstrates in detail how to implement algorithms in C++. This textbook is suitable for students who are new to the subject and covers a basic mathematical lecture course, complementing traditional courses on analysis and linear algebra. Both authors have given this "Algorithmic Mathematics" course at the University of Bonn several times in recent years.

  2. Meta-analysis of grain yield QTL identified during agricultural drought in grasses showed consensus.

    Science.gov (United States)

    Swamy, B P Mallikarjuna; Vikram, Prashant; Dixit, Shalabh; Ahmed, H U; Kumar, Arvind

    2011-06-16

    In the last few years, efforts have been made to identify large effect QTL for grain yield under drought in rice. However, identification of most precise and consistent QTL across the environments and genetics backgrounds is essential for their successful use in Marker-assisted Selection. In this study, an attempt was made to locate consistent QTL regions associated with yield increase under drought by applying a genome-wide QTL meta-analysis approach. The integration of 15 maps resulted in a consensus map with 531 markers and a total map length of 1821 cM. Fifty-three yield QTL reported in 15 studies were projected on a consensus map and meta-analysis was performed. Fourteen meta-QTL were obtained on seven chromosomes. MQTL1.2, MQTL1.3, MQTL1.4, and MQTL12.1 were around 700 kb and corresponded to a reasonably small genetic distance of 1.8 to 5 cM and they are suitable for use in marker-assisted selection (MAS). The meta-QTL for grain yield under drought coincided with at least one of the meta-QTL identified for root and leaf morphology traits under drought in earlier reports. Validation of major-effect QTL on a panel of random drought-tolerant lines revealed the presence of at least one major QTL in each line. DTY12.1 was present in 85% of the lines, followed by DTY4.1 in 79% and DTY1.1 in 64% of the lines. Comparative genomics of meta-QTL with other cereals revealed that the homologous regions of MQTL1.4 and MQTL3.2 had QTL for grain yield under drought in maize, wheat, and barley respectively. The genes in the meta-QTL regions were analyzed by a comparative genomics approach and candidate genes were deduced for grain yield under drought. Three groups of genes such as stress-inducible genes, growth and development-related genes, and sugar transport-related genes were found in clusters in most of the meta-QTL. Meta-QTL with small genetic and physical intervals could be useful in Marker-assisted selection individually and in combinations. Validation and comparative

  3. New trends in gender and mathematics performance: a meta-analysis.

    Science.gov (United States)

    Lindberg, Sara M; Hyde, Janet Shibley; Petersen, Jennifer L; Linn, Marcia C

    2010-11-01

    In this article, we use meta-analysis to analyze gender differences in recent studies of mathematics performance. First, we meta-analyzed data from 242 studies published between 1990 and 2007, representing the testing of 1,286,350 people. Overall, d = 0.05, indicating no gender difference, and variance ratio = 1.08, indicating nearly equal male and female variances. Second, we analyzed data from large data sets based on probability sampling of U.S. adolescents over the past 20 years: the National Longitudinal Surveys of Youth, the National Education Longitudinal Study of 1988, the Longitudinal Study of American Youth, and the National Assessment of Educational Progress. Effect sizes for the gender difference ranged between -0.15 and +0.22. Variance ratios ranged from 0.88 to 1.34. Taken together, these findings support the view that males and females perform similarly in mathematics.

  4. Cyclic Loading of Growing Tissue in a Bioreactor: Mathematical Model and Asymptotic Analysis

    KAUST Repository

    Pohlmeyer, J. V.

    2013-10-24

    A simplified 2D mathematical model for tissue growth within a cyclically-loaded tissue engineering scaffold is presented and analyzed. Such cyclic loading has the potential to improve yield and functionality of tissue such as bone and cartilage when grown on a scaffold within a perfusion bioreactor. The cyclic compression affects the flow of the perfused nutrient, leading to flow properties that are inherently unsteady, though periodic, on a timescale short compared with that of tissue proliferation. A two-timescale analysis based on these well-separated timescales is exploited to derive a closed model for the tissue growth on the long timescale of proliferation. Some sample numerical results are given for the final model, and discussed. © 2013 Society for Mathematical Biology.

  5. Mathematical support for automated geometry analysis of lathe machining of oblique peakless round-nose tools

    Science.gov (United States)

    Filippov, A. V.; Tarasov, S. Yu; Podgornyh, O. A.; Shamarin, N. N.; Filippova, E. O.

    2017-01-01

    Automatization of engineering processes requires developing relevant mathematical support and a computer software. Analysis of metal cutting kinematics and tool geometry is a necessary key task at the preproduction stage. This paper is focused on developing a procedure for determining the geometry of oblique peakless round-nose tool lathe machining with the use of vector/matrix transformations. Such an approach allows integration into modern mathematical software packages in distinction to the traditional analytic description. Such an advantage is very promising for developing automated control of the preproduction process. A kinematic criterion for the applicable tool geometry has been developed from the results of this study. The effect of tool blade inclination and curvature on the geometry-dependent process parameters was evaluated.

  6. Coherent structures in granular crystals from experiment and modelling to computation and mathematical analysis

    CERN Document Server

    Chong, Christopher

    2018-01-01

    This book summarizes a number of fundamental developments at the interface of granular crystals and the mathematical and computational analysis of some of their key localized nonlinear wave solutions. The subject presents a blend of the appeal of granular crystals as a prototypical engineering tested for a variety of diverse applications, the novelty in the nonlinear physics of its coherent structures, and the tractability of a series of mathematical and computational techniques to analyse them. While the focus is on principal one-dimensional solutions such as shock waves, traveling waves, and discrete breathers, numerous extensions of the discussed patterns, e.g., in two dimensions, chains with defects, heterogeneous settings, and other recent developments are discussed. The book appeals to researchers in the field, as well as for graduate and advanced undergraduate students. It will be of interest to mathematicians, physicists and engineers alike.

  7. Meta-analysis of field experiments shows no change in racial discrimination in hiring over time.

    Science.gov (United States)

    Quillian, Lincoln; Pager, Devah; Hexel, Ole; Midtbøen, Arnfinn H

    2017-10-10

    This study investigates change over time in the level of hiring discrimination in US labor markets. We perform a meta-analysis of every available field experiment of hiring discrimination against African Americans or Latinos ( n = 28). Together, these studies represent 55,842 applications submitted for 26,326 positions. We focus on trends since 1989 ( n = 24 studies), when field experiments became more common and improved methodologically. Since 1989, whites receive on average 36% more callbacks than African Americans, and 24% more callbacks than Latinos. We observe no change in the level of hiring discrimination against African Americans over the past 25 years, although we find modest evidence of a decline in discrimination against Latinos. Accounting for applicant education, applicant gender, study method, occupational groups, and local labor market conditions does little to alter this result. Contrary to claims of declining discrimination in American society, our estimates suggest that levels of discrimination remain largely unchanged, at least at the point of hire.

  8. Global Trend Analysis of Multi-decade Soil Temperature Records Show Soils Resistant to Warming

    Science.gov (United States)

    Frey, S. D.; Jennings, K.

    2017-12-01

    Soil temperature is an important determinant of many subterranean ecological processes including plant growth, nutrient cycling, and carbon sequestration. Soils are expected to warm in response to increasing global surface temperatures; however, despite the importance of soil temperature to ecosystem processes, less attention has been given to examining changes in soil temperature over time. We collected long-term (> 20 years) soil temperature records from approximately 50 sites globally, many with multiple depths (5 - 100 cm), and examined temperature trends over the last few decades. For each site and depth we calculated annual summer means and conducted non-parametric Mann Kendall trend and Sen slope analysis to assess changes in summer soil temperature over the length of each time series. The mean summer soil temperature trend across all sites and depths was not significantly different than zero (mean = 0.004 °C year-1 ± 0.033 SD), suggesting that soils have not warmed over the observation period. Of the subset of sites that exhibit significant increases in temperature over time, site location, depth of measurement, time series length, and neither start nor end date seem to be related to trend strength. These results provide evidence that the thermal regime of soils may have a stronger buffering capacity than expected, having important implications for the global carbon cycle and feedbacks to climate change.

  9. Mathematical Analysis for Non-reciprocal-interaction-based Model of Collective Behavior

    Science.gov (United States)

    Kano, Takeshi; Osuka, Koichi; Kawakatsu, Toshihiro; Ishiguro, Akio

    2017-12-01

    In many natural and social systems, collective behaviors emerge as a consequence of non-reciprocal interaction between their constituents. As a first step towards understanding the core principle that underlies these phenomena, we previously proposed a minimal model of collective behavior based on non-reciprocal interactions by drawing inspiration from friendship formation in human society, and demonstrated via simulations that various non-trivial patterns emerge by changing parameters. In this study, a mathematical analysis of the proposed model wherein the system size is small is performed. Through the analysis, the mechanism of the transition between several patterns is elucidated.

  10. VEDIC MATHEMATICS

    Directory of Open Access Journals (Sweden)

    Sead Rešić

    2015-09-01

    Full Text Available It is very difficult to motivate students when it comes to a school subject like Mathematics. Teachers spend a lot of time trying to find something that will arouse interest in students. It is particularly difficult to find materials that are motivating enough for students that they eagerly wait for the next lesson. One of the solutions may be found in Vedic Mathematics. Traditional methods of teaching Mathematics create fear of this otherwise interesting subject in the majority of students. Fear increases failure. Often the traditional, conventional mathematical methods consist of very long lessons which are difficult to understand. Vedic Mathematics is an ancient system that is very flexible and encourages the development of intuition and innovation. It is a mental calculating tool that does not require a calculator because the calculator is embedded in each of us. Starting from the above problems of fear and failure in Mathematics, the goal of this paper is to do research with the control and the experimental group and to compare the test results. Two tests should be done for each of the groups. The control group would do the tests in the conventional way. The experimental group would do the first test in a conventional manner and then be subjected to different treatment, that is to say, be taught on the basis of Vedic Mathematics. After that, the second group would do the second test according to the principles of Vedic Mathematics. Expectations are that after short lectures on Vedic mathematics results of the experimental group would improve and that students will show greater interest in Mathematics.

  11. Analysis of nonlocal phonon thermal conductivity simulations showing the ballistic to diffusive crossover

    Science.gov (United States)

    Allen, Philip B.

    2018-04-01

    Simulations [e.g., X. W. Zhou et al., Phys. Rev. B 79, 115201 (2009), 10.1103/PhysRevB.79.115201] show nonlocal effects of the ballistic/diffusive crossover. The local temperature has nonlinear spatial variation not contained in the local Fourier law j ⃗(r ⃗) =-κ ∇ ⃗T (r ⃗) . The heat current j ⃗(r ⃗) depends not just on the local temperature gradient ∇ ⃗T (r ⃗) but also on temperatures at points r⃗' within phonon mean free paths, which can be micrometers long. This paper uses the Peierls-Boltzmann transport theory in nonlocal form to analyze the spatial variation Δ T (r ⃗) . The relaxation-time approximation (RTA) is used because the full solution is very challenging. Improved methods of extrapolation to obtain the bulk thermal conductivity κ are proposed. Callaway invented an approximate method of correcting RTA for the q ⃗ (phonon wave vector or crystal momentum) conservation of N (Normal as opposed to Umklapp) anharmonic collisions. This method is generalized to the nonlocal case where κ (k ⃗) depends on the wave vector of the current j ⃗(k ⃗) and temperature gradient i k ⃗Δ T (k ⃗) .

  12. Metachronous metastasis- and survival-analysis show prognostic importance of lymphadenectomy for colon carcinomas

    Directory of Open Access Journals (Sweden)

    Laubert Tilman

    2012-03-01

    Full Text Available Abstract Background Lymphadenectomy is performed to assess patient prognosis and to prevent metastasizing. Recently, it was questioned whether lymph node metastases were capable of metastasizing and therefore, if lymphadenectomy was still adequate. We evaluated whether the nodal status impacts on the occurrence of distant metastases by analyzing a highly selected cohort of colon cancer patients. Methods 1,395 patients underwent surgery exclusively for colon cancer at the University of Lübeck between 01/1993 and 12/2008. The following exclusion criteria were applied: synchronous metastasis, R1-resection, prior/synchronous second carcinoma, age Results Five-year survival rates for TM + and TM- were 21% and 73%, respectively (p Conclusions Besides a higher T-category, a positive N-stage independently implies a higher probability to develop distant metastases and correlates with poor survival. Our data thus show a prognostic relevance of lymphadenectomy which should therefore be retained until conclusive studies suggest the unimportance of lmyphadenectomy.

  13. Tunable wavefront coded imaging system based on detachable phase mask: Mathematical analysis, optimization and underlying applications

    Science.gov (United States)

    Zhao, Hui; Wei, Jingxuan

    2014-09-01

    The key to the concept of tunable wavefront coding lies in detachable phase masks. Ojeda-Castaneda et al. (Progress in Electronics Research Symposium Proceedings, Cambridge, USA, July 5-8, 2010) described a typical design in which two components with cosinusoidal phase variation operate together to make defocus sensitivity tunable. The present study proposes an improved design and makes three contributions: (1) A mathematical derivation based on the stationary phase method explains why the detachable phase mask of Ojeda-Castaneda et al. tunes the defocus sensitivity. (2) The mathematical derivations show that the effective bandwidth wavefront coded imaging system is also tunable by making each component of the detachable phase mask move asymmetrically. An improved Fisher information-based optimization procedure was also designed to ascertain the optimal mask parameters corresponding to specific bandwidth. (3) Possible applications of the tunable bandwidth are demonstrated by simulated imaging.

  14. Effects of Video Games and Online Chat on Mathematics Performance in High School: An Approach of Multivariate Data Analysis

    OpenAIRE

    Lina Wu; Wenyi Lu; Ye Li

    2016-01-01

    Regarding heavy video game players for boys and super online chat lovers for girls as a symbolic phrase in the current adolescent culture, this project of data analysis verifies the displacement effect on deteriorating mathematics performance. To evaluate correlation or regression coefficients between a factor of playing video games or chatting online and mathematics performance compared with other factors, we use multivariate analysis technique and take gender difference into account. We fin...

  15. Effects of Gender, Mathematics Anxiety and Achievement Motivation on College Students’ Achievement in Mathematics

    Directory of Open Access Journals (Sweden)

    Ajogbeje Oke James

    2013-07-01

    Full Text Available The urge to excel or perform maximally in mathematics varies from individual to individual because achievement motivation is often developed or learnt during socialization and learning experiences. The study examined the relationship between College of Education students’ achievement motivation and mathematics achievement, correlation coefficient between mathematics anxiety and college students’ achievement motivation as well as mathematics anxiety and mathematics achievement. The sample, 268 College of Education students offering mathematics as one of their subject combination, was selected using purposive sampling techniques. Three research instruments namely: Mathematics Anxiety Scale (MAS, Achievement Motivation Scale (AMS and Mathematics Achievement Test (MAT were used to collect data for the study. Data collected for the study were analyzed using correlational analysis and ANOVA. The results showed that a significantly low negative correlation coefficient existed between mathematics anxiety and mathematics achievement. There is a negative and significant correlation coefficient between mathematics anxiety and achievement motivation. Similarly, a positive and significant correlation coefficient also exists between achievement motivation and mathematics achievement. Based on the findings of the study, it was recommended that mathematics teachers should adopt activity based strategies and conducive learning environment in order to reduce college students’ anxieties in mathematics learning.

  16. M and c'99 : Mathematics and computation, reactor physics and environmental analysis in nuclear applications, Madrid, September 27-30, 1999

    International Nuclear Information System (INIS)

    Aragones, J. M.; Ahnert, C.; Cabellos, O.

    1999-01-01

    The international conference on mathematics and computation, reactor physics and environmental analysis in nuclear applications in the biennial topical meeting of the mathematics and computation division of the American Nuclear Society. (Author)

  17. M and c'99 : Mathematics and computation, reactor physics and environmental analysis in nuclear applications, Madrid, September 27-30, 1999

    Energy Technology Data Exchange (ETDEWEB)

    Aragones, J. M.; Ahnert, C.; Cabellos, O.

    1999-07-01

    The international conference on mathematics and computation, reactor physics and environmental analysis in nuclear applications in the biennial topical meeting of the mathematics and computation division of the American Nuclear Society. (Author)

  18. The Unit of Analysis in Mathematics Education: Bridging the Political-Technical Divide?

    Science.gov (United States)

    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.…

  19. Mathematical 3D modelling and sensitivity analysis of multipolar radiofrequency ablation in the spine.

    Science.gov (United States)

    Matschek, Janine; Bullinger, Eric; von Haeseler, Friedrich; Skalej, Martin; Findeisen, Rolf

    2017-02-01

    Radiofrequency ablation is a valuable tool in the treatment of many diseases, especially cancer. However, controlled heating up to apoptosis of the desired target tissue in complex situations, e.g. in the spine, is challenging and requires experienced interventionalists. For such challenging situations a mathematical model of radiofrequency ablation allows to understand, improve and optimise the outcome of the medical therapy. The main contribution of this work is the derivation of a tailored, yet expandable mathematical model, for the simulation, analysis, planning and control of radiofrequency ablation in complex situations. The dynamic model consists of partial differential equations that describe the potential and temperature distribution during intervention. To account for multipolar operation, time-dependent boundary conditions are introduced. Spatially distributed parameters, like tissue conductivity and blood perfusion, allow to describe the complex 3D environment representing diverse involved tissue types in the spine. To identify the key parameters affecting the prediction quality of the model, the influence of the parameters on the temperature distribution is investigated via a sensitivity analysis. Simulations underpin the quality of the derived model and the analysis approach. The proposed modelling and analysis schemes set the basis for intervention planning, state- and parameter estimation, and control. Copyright © 2016. Published by Elsevier Inc.

  20. Mathematical modeling

    CERN Document Server

    Eck, Christof; Knabner, Peter

    2017-01-01

    Mathematical models are the decisive tool to explain and predict phenomena in the natural and engineering sciences. With this book readers will learn to derive mathematical models which help to understand real world phenomena. At the same time a wealth of important examples for the abstract concepts treated in the curriculum of mathematics degrees are given. An essential feature of this book is that mathematical structures are used as an ordering principle and not the fields of application. Methods from linear algebra, analysis and the theory of ordinary and partial differential equations are thoroughly introduced and applied in the modeling process. Examples of applications in the fields electrical networks, chemical reaction dynamics, population dynamics, fluid dynamics, elasticity theory and crystal growth are treated comprehensively.

  1. Mathematical analysis of a model for the growth of the bovine corpus luteum

    KAUST Repository

    Prokopiou, Sotiris A.

    2013-12-13

    The corpus luteum (CL) is an ovarian tissue that grows in the wound space created by follicular rupture. It produces the progesterone needed in the uterus to maintain pregnancy. Rapid growth of the CL and progesterone transport to the uterus require angiogenesis, the creation of new blood vessels from pre-existing ones, a process which is regulated by proteins that include fibroblast growth factor 2 (FGF2). In this paper we develop a system of time-dependent ordinary differential equations to model CL growth. The dependent variables represent FGF2, endothelial cells (ECs), luteal cells, and stromal cells (like pericytes), by assuming that the CL volume is a continuum of the three cell types. We assume that if the CL volume exceeds that of the ovulated follicle, then growth is inhibited. This threshold volume partitions the system dynamics into two regimes, so that the model may be classified as a Filippov (piecewise smooth) system. We show that normal CL growth requires an appropriate balance between the growth rates of luteal and stromal cells. We investigate how angiogenesis influences CL growth by considering how the system dynamics depend on the dimensionless EC proliferation rate, {Mathematical expression}. We find that weak (low {Mathematical expression}) or strong (high {Mathematical expression}) angiogenesis leads to \\'pathological\\' CL growth, since the loss of CL constituents compromises progesterone production or delivery. However, for intermediate values of {Mathematical expression}, normal CL growth is predicted. The implications of these results for cow fertility are also discussed. For example, inadequate angiogenesis has been linked to infertility in dairy cows. © 2013 Springer-Verlag Berlin Heidelberg.

  2. Contributions to mathematical analysis and to numerical approximation in plasma physics

    International Nuclear Information System (INIS)

    Besse, N.

    2009-01-01

    The author's scientific works deal with numerical analysis and the simulation of the partial differential equations that intervene in the transport of charged particles and in plasma physics. In the chapters 2 and 3, a reduction of the Vlasov equation is presented, this method is based on the Liouville geometric invariants and it leads to a mathematical model named water-bag model that can be coupled with various equations of the electromagnetic field: the Poisson equation, the quasi-neutral equation or Maxwell equations. In the chapter 3 this reduction method is applied to the Vlasov gyro-kinetic equation to form the gyro-water-bag model. The mathematical analysis of this model produces interesting analytical results such as: threshold instabilities, instability growth rate, transport coefficient and non-linear turbulence mechanisms. Simulations have been performed to study turbulence in magnetized plasmas. In these plasmas occurred numerous instabilities due to the presence of high density and temperature gradients. These instabilities generate turbulence that deteriorates plasma confinement conditions required for thermonuclear fusion. The numerical calculation of turbulent thermal diffusivities is important since confinement time is determined by these transport coefficients. The chapter 4 gathers mathematical analysis issues like convergence or prior knowledge of errors concerning several high-order numerical methods used to solve Vlasov-Poisson or Vlasov-Einstein equation systems as well as the induction equation of an idealistic MHD system. The chapter 5 presents original numerical methods to solve several non-linear Vlasov equations such as Vlasov-Poisswell, Vlasov-Darwin, Vlasov-Maxwell and Vlasov-gyrokinetic that are involved either in inertial fusion or in magnetic confinement fusion

  3. Mathematical physiology

    CERN Document Server

    Sneyd, James

    2009-01-01

    There has been a long history of interaction between mathematics and physiology. This book looks in detail at a wide selection of mathematical models in physiology, showing how physiological problems can be formulated and studied mathematically, and how such models give rise to interesting and challenging mathematical questions. With its coverage of many recent models it gives an overview of the field, while many older models are also discussed, to put the modern work in context. In this second edition the coverage of basic principles has been expanded to include such topics as stochastic differential equations, Markov models and Gibbs free energy, and the selection of models has also been expanded to include some of the basic models of fluid transport, respiration/perfusion, blood diseases, molecular motors, smooth muscle, neuroendrocine cells, the baroreceptor loop, turboglomerular oscillations, blood clotting and the retina. Owing to this extensive coverage, the second edition is published in two volumes. ...

  4. Mathematical analysis of the dimensional scaling technique for the Schroedinger equation with power-law potentials

    International Nuclear Information System (INIS)

    Ding Zhonghai; Chen, Goong; Lin, Chang-Shou

    2010-01-01

    The dimensional scaling (D-scaling) technique is an innovative asymptotic expansion approach to study the multiparticle systems in molecular quantum mechanics. It enables the calculation of ground and excited state energies of quantum systems without having to solve the Schroedinger equation. In this paper, we present a mathematical analysis of the D-scaling technique for the Schroedinger equation with power-law potentials. By casting the D-scaling technique in an appropriate variational setting and studying the corresponding minimization problem, the D-scaling technique is justified rigorously. A new asymptotic dimensional expansion scheme is introduced to compute asymptotic expansions for ground state energies.

  5. Latent transition analysis of pre-service teachers' efficacy in mathematics and science

    Science.gov (United States)

    Ward, Elizabeth Kennedy

    This study modeled changes in pre-service teacher efficacy in mathematics and science over the course of the final year of teacher preparation using latent transition analysis (LTA), a longitudinal form of analysis that builds on two modeling traditions (latent class analysis (LCA) and auto-regressive modeling). Data were collected using the STEBI-B, MTEBI-r, and the ABNTMS instruments. The findings suggest that LTA is a viable technique for use in teacher efficacy research. Teacher efficacy is modeled as a construct with two dimensions: personal teaching efficacy (PTE) and outcome expectancy (OE). Findings suggest that the mathematics and science teaching efficacy (PTE) of pre-service teachers is a multi-class phenomena. The analyses revealed a four-class model of PTE at the beginning and end of the final year of teacher training. Results indicate that when pre-service teachers transition between classes, they tend to move from a lower efficacy class into a higher efficacy class. In addition, the findings suggest that time-varying variables (attitudes and beliefs) and time-invariant variables (previous coursework, previous experiences, and teacher perceptions) are statistically significant predictors of efficacy class membership. Further, analyses suggest that the measures used to assess outcome expectancy are not suitable for LCA and LTA procedures.

  6. Mathematic model analysis of Gaussian beam propagation through an arbitrary thickness random phase screen.

    Science.gov (United States)

    Tian, Yuzhen; Guo, Jin; Wang, Rui; Wang, Tingfeng

    2011-09-12

    In order to research the statistical properties of Gaussian beam propagation through an arbitrary thickness random phase screen for adaptive optics and laser communication application in the laboratory, we establish mathematic models of statistical quantities, which are based on the Rytov method and the thin phase screen model, involved in the propagation process. And the analytic results are developed for an arbitrary thickness phase screen based on the Kolmogorov power spectrum. The comparison between the arbitrary thickness phase screen and the thin phase screen shows that it is more suitable for our results to describe the generalized case, especially the scintillation index.

  7. Local Stability Analysis of an Infection-Age Mathematical Model for ...

    African Journals Online (AJOL)

    Timothy

    1Department of Mathematics/Statistics/Computer Science, Federal University of Agriculture, Makurdi, ... ABSTRACT: An infection age structured mathematical model for tuberculosis disease ...... its applications to optimal vaccination strategies.

  8. Mathematical analysis of frontal affinity chromatography in particle and membrane configurations.

    Science.gov (United States)

    Tejeda-Mansir, A; Montesinos, R M; Guzmán, R

    2001-10-30

    The scaleup and optimization of large-scale affinity-chromatographic operations in the recovery, separation and purification of biochemical components is of major industrial importance. The development of mathematical models to describe affinity-chromatographic processes, and the use of these models in computer programs to predict column performance is an engineering approach that can help to attain these bioprocess engineering tasks successfully. Most affinity-chromatographic separations are operated in the frontal mode, using fixed-bed columns. Purely diffusive and perfusion particles and membrane-based affinity chromatography are among the main commercially available technologies for these separations. For a particular application, a basic understanding of the main similarities and differences between particle and membrane frontal affinity chromatography and how these characteristics are reflected in the transport models is of fundamental relevance. This review presents the basic theoretical considerations used in the development of particle and membrane affinity chromatography models that can be applied in the design and operation of large-scale affinity separations in fixed-bed columns. A transport model for column affinity chromatography that considers column dispersion, particle internal convection, external film resistance, finite kinetic rate, plus macropore and micropore resistances is analyzed as a framework for exploring further the mathematical analysis. Such models provide a general realistic description of almost all practical systems. Specific mathematical models that take into account geometric considerations and transport effects have been developed for both particle and membrane affinity chromatography systems. Some of the most common simplified models, based on linear driving-force (LDF) and equilibrium assumptions, are emphasized. Analytical solutions of the corresponding simplified dimensionless affinity models are presented. Particular

  9. Mathematics without boundaries surveys in pure mathematics

    CERN Document Server

    Pardalos, Panos

    2014-01-01

    The contributions in this volume have been written by eminent scientists from the international mathematical community and present significant advances in several theories, methods and problems of Mathematical Analysis, Discrete Mathematics, Geometry and their Applications. The chapters focus on both old and recent developments in Functional Analysis, Harmonic Analysis, Complex Analysis, Operator Theory, Combinatorics, Functional Equations, Differential Equations as well as a variety of Applications. The book also contains some review works, which could prove particularly useful for a broader audience of readers in Mathematical Sciences, and especially to graduate students looking for the  latest information.

  10. Heat integration of an Olefins Plant: Pinch Analysis and mathematical optimization working together

    Directory of Open Access Journals (Sweden)

    M. Beninca

    2011-03-01

    Full Text Available This work explores a two-step, complexity reducing methodology, to analyze heat integration opportunities of an existing Olefins Plant, identify and quantify reduction of energy consumption, and propose changes of the existing heat exchanger network to achieve these goals. Besides the analysis of plant design conditions, multiple operational scenarios were considered to propose modifications for handling real plant operation (flexibility. On the strength of plant complexity and large dimension, work methodology was split into two parts: initially, the whole plant was evaluated with traditional Pinch Analysis tools. Several opportunities were identified and modifications proposed. Modifications were segregated to represent small and independent portions of the original process. One of them was selected to be re-analyzed, considering two scenarios. Reduction of problem dimension allowed mathematical methodologies (formulation with decomposition, applying LP, MILP and NLP optimization methods to synthesize flexible networks to be applied, generating a feasible modification capable of fulfilling the proposed operational scenarios.

  11. Exploring Differential Effects of Mathematics Courses on Mathematics Achievement

    Science.gov (United States)

    Ma, Xin; McIntyre, Laureen J.

    2005-01-01

    Using data from the Longitudinal Study of Mathematics Participation (N = 1,518 students from 34 schools), we investigated the effects of pure and applied mathematics courses on mathematics achievement, controlling for prior mathematics achievement. Results of multilevel modelling showed that the effects of pure mathematics were significant after…

  12. Analysis of mathematical problem-solving ability based on metacognition on problem-based learning

    Science.gov (United States)

    Mulyono; Hadiyanti, R.

    2018-03-01

    Problem-solving is the primary purpose of the mathematics curriculum. Problem-solving abilities influenced beliefs and metacognition. Metacognition as superordinate capabilities can direct, regulate cognition and motivation and then problem-solving processes. This study aims to (1) test and analyzes the quality of problem-based learning and (2) investigate the problem-solving capabilities based on metacognition. This research uses mixed method study with The subject research are class XI students of Mathematics and Science at High School Kesatrian 2 Semarang which divided into tacit use, aware use, strategic use and reflective use level. The collecting data using scale, interviews, and tests. The data processed with the proportion of test, t-test, and paired samples t-test. The result shows that the students with levels tacit use were able to complete the whole matter given, but do not understand what and why a strategy is used. Students with aware use level were able to solve the problem, be able to build new knowledge through problem-solving to the indicators, understand the problem, determine the strategies used, although not right. Students on the Strategic ladder Use can be applied and adopt a wide variety of appropriate strategies to solve the issues and achieved re-examine indicators of process and outcome. The student with reflective use level is not found in this study. Based on the results suggested that study about the identification of metacognition in problem-solving so that the characteristics of each level of metacognition more clearly in a more significant sampling. Teachers need to know in depth about the student metacognitive activity and its relationship with mathematical problem solving and another problem resolution.

  13. An Intersectional Analysis of Latin@ College Women's Counter-Stories in Mathematics

    Science.gov (United States)

    Leyva, Luis A.

    2016-01-01

    In this article, the author discusses the intersectionality of mathematics experiences for two Latin@ college women pursuing mathematics-intensive STEM (science, technology, engineering, and mathematics) majors at a large, predominantly White university. The author employs intersectionality and poststructural theories to explore and make meaning…

  14. Intersectional Analysis in Critical Mathematics Education Research: A Response to Figure Hiding

    Science.gov (United States)

    Bullock, Erika C.

    2018-01-01

    In this chapter, I use figure hiding as a metaphor representing the processes of exclusion and suppression that critical mathematics education (CME) seeks to address. Figure hiding renders identities and modes of thought in mathematics education and mathematics education research invisible. CME has a commitment to addressing figure hiding by…

  15. An Analysis of Instruments that Measure the Quality of Mathematics Teaching in Early Childhood

    Science.gov (United States)

    Kilday, Carolyn R.; Kinzie, Mable B.

    2009-01-01

    The evaluation of teaching quality in mathematics has become increasingly important following research reports indicating that preschoolers are developmentally able to engage in mathematic thought and that child performance in mathematics at this level is a strong predictor of later school achievement. As attention turns to early mathematics…

  16. Kindergarten Children's Interactions with Touchscreen Mathematics Virtual Manipulatives: An Innovative Mixed Methods Analysis

    Science.gov (United States)

    Tucker, Stephen I.; Lommatsch, Christina W.; Moyer-Packenham, Patricia S.; Anderson-Pence, Katie L.; Symanzik, Jürgen

    2017-01-01

    The purpose of this study was to examine patterns of mathematical practices evident during children's interactions with touchscreen mathematics virtual manipulatives. Researchers analyzed 33 Kindergarten children's interactions during activities involving apps featuring mathematical content of early number sense or quantity in base ten, recorded…

  17. A Content Analysis Study about the Usage of History of Mathematics in Textbooks in Turkey

    Science.gov (United States)

    Eren, Mehmet; Bulut, Mehmet; Bulut, Neslihan

    2015-01-01

    The present study aimed to investigate how history of mathematics was integrated to some mathematics textbooks in Turkey. On this account, four different textbooks with different grade levels were chosen. In total, 42 cases were detected and studied by three researchers. Results indicated that the usage of history of mathematics was materialized…

  18. Explanation, Motivation and Question Posing Routines in University Mathematics Teachers' Pedagogical Discourse: A Commognitive Analysis

    Science.gov (United States)

    Viirman, Olov

    2015-01-01

    This paper investigates the teaching practices used by university mathematics teachers when lecturing, a topic within university mathematics education research which is gaining an increasing interest. In the study, a view of mathematics teaching as a discursive practice is taken, and Sfard's commognitive framework is used to investigate the…

  19. Profile of mathematics anxiety of 7th graders

    Science.gov (United States)

    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.

  20. Perfection Of Methods Of Mathematical Analysis For Increasing The Completeness Of Subsoil Development

    Science.gov (United States)

    Fokina, Mariya

    2017-11-01

    The economy of Russia is based around the mineral-raw material complex to the highest degree. The mining industry is a prioritized and important area. Given the high competitiveness of businesses in this sector, increasing the efficiency of completed work and manufactured products will become a central issue. Improvement of planning and management in this sector should be based on multivariant study and the optimization of planning decisions, the appraisal of their immediate and long-term results, taking the dynamic of economic development into account. All of this requires the use of economic mathematic models and methodsApplying an economic-mathematic model to determine optimal ore mine production capacity, we receive a figure of 4,712,000 tons. The production capacity of the Uchalinsky ore mine is 1560 thousand tons, and the Uzelginsky ore mine - 3650 thousand. Conducting a corresponding analysis of the production of OAO "Uchalinsky Gok", an optimal production plan was received: the optimal production of copper - 77961,4 rubles; the optimal production of zinc - 17975.66 rubles. The residual production volume of the two main ore mines of OAO "UGOK" is 160 million tons of ore.

  1. Analysis of Mathematical Communication Skills and Confidence of 10th Grader of SMK in Geometry Material Viewed from Cognitive Style

    Directory of Open Access Journals (Sweden)

    Elanda Laksinta Putri

    2017-03-01

    Full Text Available The purpose of this study were to describe the mathematical communication skills and the confidence of grade X SMK students on Van Hiele model geometry learning based on their cognitive styles. It was a qualitative descriptive research. The subjects were 2 impulsive students and 2 reflective students which were selected with MFFT instrument. The data collection techniques were mathematical communication skills tests (written and orally, interviews, documentation, attitude scale and activity observation sheets. The results showed that both written and orally, reflective students were able to meet 5 indicators of mathematical communication skills, and less meet another indicators. While, impulsive students less meet all of the mathematical communication skills indictors. The impulsive students confidence was in the medium category. In contrary, the reflective students confidence was in the high category.

  2. Physical disintegration of toilet papers in wastewater systems: experimental analysis and mathematical modeling.

    Science.gov (United States)

    Eren, Beytullah; Karadagli, Fatih

    2012-03-06

    Physical disintegration of representative toilet papers was investigated in this study to assess their disintegration potential in sewer systems. Characterization of toilet papers from different parts of the world indicated two main categories as premium and average quality. Physical disintegration experiments were conducted with representative products from each category according to standard protocols with improvements. The experimental results were simulated by mathematical model to estimate best-fit values of disintegration rate coefficients and fractional distribution ratios. Our results from mathematical modeling and experimental work show that premium products release more amounts of small fibers and disintegrate more slowly than average ones. Comparison of the toilet papers with the tampon applicators studied previously indicates that premium quality toilet papers present significant potential to persist in sewer pipes. Comparison of turbulence level in our experimental setup with those of partial flow conditions in sewer pipes indicates that drains and small sewer pipes are critical sections where disintegration of toilet papers will be limited. For improvement, requirements for minimum pipe slopes may be increased to sustain transport and disintegration of flushable products in small pipes. In parallel, toilet papers can be improved to disintegrate rapidly in sewer systems, while they meet consumer expectations.

  3. Mathematical biophysics

    CERN Document Server

    Rubin, Andrew

    2014-01-01

    This book presents concise descriptions and analysis of the classical and modern models used in mathematical biophysics. The authors ask the question "what new information can be provided by the models that cannot be obtained directly from experimental data?" Actively developing fields such as regulatory mechanisms in cells and subcellular systems and electron transport and energy transport in membranes are addressed together with more classical topics such as metabolic processes, nerve conduction and heart activity, chemical kinetics, population dynamics, and photosynthesis. The main approach is to describe biological processes using different mathematical approaches necessary to reveal characteristic features and properties of simulated systems. With the emergence of powerful mathematics software packages such as MAPLE, Mathematica, Mathcad, and MatLab, these methodologies are now accessible to a wide audience. Provides succinct but authoritative coverage of a broad array of biophysical topics and models Wr...

  4. Physical mathematics

    CERN Document Server

    Cahill, Kevin

    2013-01-01

    Unique in its clarity, examples and range, Physical Mathematics explains as simply as possible the mathematics that graduate students and professional physicists need in their courses and research. The author illustrates the mathematics with numerous physical examples drawn from contemporary research. In addition to basic subjects such as linear algebra, Fourier analysis, complex variables, differential equations and Bessel functions, this textbook covers topics such as the singular-value decomposition, Lie algebras, the tensors and forms of general relativity, the central limit theorem and Kolmogorov test of statistics, the Monte Carlo methods of experimental and theoretical physics, the renormalization group of condensed-matter physics and the functional derivatives and Feynman path integrals of quantum field theory.

  5. A mathematical analysis of the effects of Hebbian learning rules on the dynamics and structure of discrete-time random recurrent neural networks.

    Science.gov (United States)

    Siri, Benoît; Berry, Hugues; Cessac, Bruno; Delord, Bruno; Quoy, Mathias

    2008-12-01

    We present a mathematical analysis of the effects of Hebbian learning in random recurrent neural networks, with a generic Hebbian learning rule, including passive forgetting and different timescales, for neuronal activity and learning dynamics. Previous numerical work has reported that Hebbian learning drives the system from chaos to a steady state through a sequence of bifurcations. Here, we interpret these results mathematically and show that these effects, involving a complex coupling between neuronal dynamics and synaptic graph structure, can be analyzed using Jacobian matrices, which introduce both a structural and a dynamical point of view on neural network evolution. Furthermore, we show that sensitivity to a learned pattern is maximal when the largest Lyapunov exponent is close to 0. We discuss how neural networks may take advantage of this regime of high functional interest.

  6. Mathematical models for estimating earthquake casualties and damage cost through regression analysis using matrices

    International Nuclear Information System (INIS)

    Urrutia, J D; Bautista, L A; Baccay, E B

    2014-01-01

    The aim of this study was to develop mathematical models for estimating earthquake casualties such as death, number of injured persons, affected families and total cost of damage. To quantify the direct damages from earthquakes to human beings and properties given the magnitude, intensity, depth of focus, location of epicentre and time duration, the regression models were made. The researchers formulated models through regression analysis using matrices and used α = 0.01. The study considered thirty destructive earthquakes that hit the Philippines from the inclusive years 1968 to 2012. Relevant data about these said earthquakes were obtained from Philippine Institute of Volcanology and Seismology. Data on damages and casualties were gathered from the records of National Disaster Risk Reduction and Management Council. This study will be of great value in emergency planning, initiating and updating programs for earthquake hazard reduction in the Philippines, which is an earthquake-prone country.

  7. The mathematics of the modernist villa architectural analysis using space syntax and isovists

    CERN Document Server

    Ostwald, Michael J

    2018-01-01

    This book presents the first detailed mathematical analysis of the social, cognitive and experiential properties of Modernist domestic architecture. The Modern Movement in architecture, which came to prominence during the first half of the twentieth century, may have been famous for its functional forms and machine-made aesthetic, but it also sought to challenge the way people inhabit, understand and experience space. Ludwig Mies van der Rohe’s buildings were not only minimalist and transparent, they were designed to subvert traditional social hierarchies. Frank Lloyd Wright’s organic Modernism not only attempted to negotiate a more responsive relationship between nature and architecture, but also shape the way people experience space. Richard Neutra’s Californian Modernism is traditionally celebrated for its sleek, geometric forms, but his intention was to use design to support a heightened understanding of context. Glenn Murcutt’s pristine pavilions, seemingly the epitome of regional Modernism, actu...

  8. Assessing the sense of `good at' and `not good at' toward learning topics of mathematics with conjoint analysis

    Science.gov (United States)

    Izuta, Giido; Nishikawa, Tomoko

    2017-05-01

    Over the past years, educational psychology and pedagogy communities have focused on the metacognition formalism as a helpful approach to carry out investigations on the feeling of difficulty in mastering some classroom materials that students acquire through their subjective experiences of learning in schools. Motivated by hitherto studies, this work deals with the assessment of the awareness of `good at' and `not good at' that Japanese junior high school students have towards the main learning modules in their three years of mathematics. More specifically, the aims here are (i) to shed some light into how the awareness varies across the grades and gender; (ii) to get some insights into the extent to what the conjoint analysis can be applied to understand the students' feelings toward learning activities. To accomplish them, a conjoint analysis survey with three conjoint attributes, each with two levels, were designed to assess the learners' perceptions of `good at' and `not good at' with respect to arithmetic (algebraic operations), geometry and functions, which make up the three major modules of their curricula. The measurements took place in a public junior high school with 616 school children. It turned out that the conjoint analyses for boys and girls of each grade generated the partial utility and importance graphs which along with a pre-established precision of measurement allowed us to form groups of pupils according to their `sense of being good at' characteristics. Moreover, the results showed that the number of groups obtained differed for boys and girls as well as grades when the gender and school years were considered for comparisons. These findings suggesting that female students outnumbers their peers in number of `good at' despite the low number of females pursuing careers in mathematics and related fields imply that investigation on the causes of this juxtaposition has to be taken into account in the future.

  9. The influence of mathematics learning using SAVI approach on junior high school students’ mathematical modelling ability

    Science.gov (United States)

    Khusna, H.; Heryaningsih, N. Y.

    2018-01-01

    The aim of this research was to examine mathematical modeling ability who learn mathematics by using SAVI approach. This research was a quasi-experimental research with non-equivalent control group designed by using purposive sampling technique. The population of this research was the state junior high school students in Lembang while the sample consisted of two class at 8th grade. The instrument used in this research was mathematical modeling ability. Data analysis of this research was conducted by using SPSS 20 by Windows. The result showed that students’ ability of mathematical modeling who learn mathematics by using SAVI approach was better than students’ ability of mathematical modeling who learn mathematics using conventional learning.

  10. Dependence of the firearm-related homicide rate on gun availability: a mathematical analysis.

    Science.gov (United States)

    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.

  11. 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.

  12. Analysis of critical thinking ability of VII grade students based on the mathematical anxiety level through learning cycle 7E model

    Science.gov (United States)

    Widyaningsih, E.; Waluya, S. B.; Kurniasih, A. W.

    2018-03-01

    This study aims to know mastery learning of students’ critical thinking ability with learning cycle 7E, determine whether the critical thinking ability of the students with learning cycle 7E is better than students’ critical thinking ability with expository model, and describe the students’ critical thinking phases based on the mathematical anxiety level. The method is mixed method with concurrent embedded. The population is VII grade students of SMP Negeri 3 Kebumen academic year 2016/2017. Subjects are determined by purposive sampling, selected two students from each level of mathematical anxiety. Data collection techniques include test, questionnaire, interview, and documentation. Quantitative data analysis techniques include mean test, proportion test, difference test of two means, difference test of two proportions and for qualitative data used Miles and Huberman model. The results show that: (1) students’ critical thinking ability with learning cycle 7E achieve mastery learning; (2) students’ critical thinking ability with learning cycle 7E is better than students’ critical thinking ability with expository model; (3) description of students’ critical thinking phases based on the mathematical anxiety level that is the lower the mathematical anxiety level, the subjects have been able to fulfil all of the indicators of clarification, assessment, inference, and strategies phases.

  13. The analysis of the mathematics concept comprehension of senior high school student on dynamic fluid material

    Science.gov (United States)

    Kristian, P. L. Y.; Cari, C.; Sunarno, W.

    2018-04-01

    This study purposes to describe and analyse the students' concept understanding of dynamic fluid. The subjects of this research are 10 students of senior high school. The data collected finished the essay test that consists of 5 questions have been adapted to the indicators of learning. The data of this research is analysed using descriptive-qualitative approach by referring of the student's argumentations about their answer from the questions that given. The results showed that students still have incorrect understanding the concept of dynamic fluids, especially on the Bernoulli’s principle and its application. Based on the results of this research, the teachers should emphasize the concept understanding of the students therefore the students don not only understand the physics concept in mathematical form.

  14. An Invitation to Mathematics

    CERN Document Server

    Schleicher, Dierk

    2011-01-01

    This "Invitation to Mathematics" consists of 14 contributions, many from the world's leading mathematicians, which introduce the readers to exciting aspects of current mathematical research. The contributions are as varied as the personalities of active mathematicians, but together they show mathematics as a rich and lively field of research. The contributions are written for interested students at the age of transition between high school and university who know high school mathematics and perhaps competition mathematics and who want to find out what current research mathematics is

  15. Proteomic Analysis Shows Constitutive Secretion of MIF and p53-associated Activity of COX-2−/− Lung Fibroblasts

    Directory of Open Access Journals (Sweden)

    Mandar Dave

    2017-12-01

    Full Text Available The differential expression of two closelyassociated cyclooxygenase isozymes, COX-1 and COX-2, exhibited functions beyond eicosanoid metabolism. We hypothesized that COX-1 or COX-2 knockout lung fibroblasts may display altered protein profiles which may allow us to further differentiate the functional roles of these isozymes at the molecular level. Proteomic analysis shows constitutive production of macrophage migration inhibitory factor (MIF in lung fibroblasts derived from COX-2−/− but not wild-type (WT or COX-1−/− mice. MIF was spontaneously released in high levels into the extracellular milieu of COX2−/− fibroblasts seemingly from the preformed intracellular stores, with no change in the basal gene expression of MIF. The secretion and regulation of MIF in COX-2−/− was “prostaglandin-independent.” GO analysis showed that concurrent with upregulation of MIF, there is a significant surge in expression of genes related to fibroblast growth, FK506 binding proteins, and isomerase activity in COX-2−/− cells. Furthermore, COX-2−/− fibroblasts also exhibit a significant increase in transcriptional activity of various regulators, antagonists, and co-modulators of p53, as well as in the expression of oncogenes and related transcripts. Integrative Oncogenomics Cancer Browser (IntroGen analysis shows downregulation of COX-2 and amplification of MIF and/or p53 activity during development of glioblastomas, ependymoma, and colon adenomas. These data indicate the functional role of the MIF-COX-p53 axis in inflammation and cancer at the genomic and proteomic levels in COX-2-ablated cells. This systematic analysis not only shows the proinflammatory state but also unveils a molecular signature of a pro-oncogenic state of COX-1 in COX-2 ablated cells.

  16. Modern Versus Traditional Mathematics

    Science.gov (United States)

    Roberts, A. M.

    1974-01-01

    The effect of different secondary school mathematics syllabi on first-year performance in college-level mathematics was studied in an attempt to evaluate the syllabus change. Students with a modern mathematics background performed sigficantly better on most first-year units. A topic-by-topic analysis of results is included. (DT)

  17. Genomic analysis of codon usage shows influence of mutation pressure, natural selection, and host features on Marburg virus evolution.

    Science.gov (United States)

    Nasrullah, Izza; Butt, Azeem M; Tahir, Shifa; Idrees, Muhammad; Tong, Yigang

    2015-08-26

    The Marburg virus (MARV) has a negative-sense single-stranded RNA genome, belongs to the family Filoviridae, and is responsible for several outbreaks of highly fatal hemorrhagic fever. Codon usage patterns of viruses reflect a series of evolutionary changes that enable viruses to shape their survival rates and fitness toward the external environment and, most importantly, their hosts. To understand the evolution of MARV at the codon level, we report a comprehensive analysis of synonymous codon usage patterns in MARV genomes. Multiple codon analysis approaches and statistical methods were performed to determine overall codon usage patterns, biases in codon usage, and influence of various factors, including mutation pressure, natural selection, and its two hosts, Homo sapiens and Rousettus aegyptiacus. Nucleotide composition and relative synonymous codon usage (RSCU) analysis revealed that MARV shows mutation bias and prefers U- and A-ended codons to code amino acids. Effective number of codons analysis indicated that overall codon usage among MARV genomes is slightly biased. The Parity Rule 2 plot analysis showed that GC and AU nucleotides were not used proportionally which accounts for the presence of natural selection. Codon usage patterns of MARV were also found to be influenced by its hosts. This indicates that MARV have evolved codon usage patterns that are specific to both of its hosts. Moreover, selection pressure from R. aegyptiacus on the MARV RSCU patterns was found to be dominant compared with that from H. sapiens. Overall, mutation pressure was found to be the most important and dominant force that shapes codon usage patterns in MARV. To our knowledge, this is the first detailed codon usage analysis of MARV and extends our understanding of the mechanisms that contribute to codon usage and evolution of MARV.

  18. Mathematics related anxiety: Mathematics bogeyman or not?

    Directory of Open Access Journals (Sweden)

    Videnović Marina

    2011-01-01

    Full Text Available Data of the PISA 2003 survey indicate high levels of mathematics anxiety of students in Serbia. More than half of our students worry whether they will have difficulties in mathematics class or whether they will earn poor marks. Aims of this study therefore are: examining relationship between math anxiety and achievement at mathematics literacy scale; establishing possible predictors of math anxiety and identification of students' groups in relations to their relationship towards mathematics as a subject. Mathematics anxiety is statistically negatively correlated with school achievement and achievement at mathematics literacy scale. Socio-demographic factors, motivational and cognitive aspects related to learning mathematics, perception of school and classroom climate explain 40% variance of mathematics anxiety. Based on students' relationship towards mathematics they cam be divided into three groups; while dimensions that apart them are uninterested-interested in mathematics and presence-absence of anxiety. The group displaying anxiety scores lowest among the three. Applying qualitative analysis students' and teachers' attitudes on specific issues related to teaching and learning mathematics was examined.

  19. A Signal Based Triangular Structuring Element for Mathematical Morphological Analysis and Its Application in Rolling Element Bearing Fault Diagnosis

    Directory of Open Access Journals (Sweden)

    Zhaowen Chen

    2014-01-01

    Full Text Available Mathematical morphology (MM is an efficient nonlinear signal processing tool. It can be adopted to extract fault information from bearing signal according to a structuring element (SE. Since the bearing signal features differ for every unique cause of failure, the SEs should be well tailored to extract the fault feature from a particular signal. In the following, a signal based triangular SE according to the statistics of the magnitude of a vibration signal is proposed, together with associated methodology, which processes the bearing signal by MM analysis based on proposed SE to get the morphology spectrum of a signal. A correlation analysis on morphology spectrum is then employed to obtain the final classification of bearing faults. The classification performance of the proposed method is evaluated by a set of bearing vibration signals with inner race, ball, and outer race faults, respectively. Results show that all faults can be detected clearly and correctly. Compared with a commonly used flat SE, the correlation analysis on morphology spectrum with proposed SE gives better performance at fault diagnosis of bearing, especially the identification of the location of outer race fault and the level of fault severity.

  20. Mathematical Sciences in Australia

    Science.gov (United States)

    Thomas, Jan; Muchatuta, Michelle; Wood, Leigh

    2009-01-01

    This article investigates enrolment trends in mathematical sciences in Australian universities. Data has been difficult to extract and the coding for mathematical disciplines has made investigation challenging. We show that the number of mathematics major undergraduates in Australia is steadily declining though the number studying…

  1. Development of Contextual Mathematics teaching Material integrated related sciences and realistic for students grade xi senior high school

    Science.gov (United States)

    Helma, H.; Mirna, M.; Edizon, E.

    2018-04-01

    Mathematics is often applied in physics, chemistry, economics, engineering, and others. Besides that, mathematics is also used in everyday life. Learning mathematics in school should be associated with other sciences and everyday life. In this way, the learning of mathematics is more realstic, interesting, and meaningful. Needs analysis shows that required contextual mathematics teaching materials integrated related sciences and realistic on learning mathematics. The purpose of research is to produce a valid and practical contextual mathematics teaching material integrated related sciences and realistic. This research is development research. The result of this research is a valid and practical contextual mathematics teaching material integrated related sciences and realistic produced

  2. A comparative analysis of quadratics in mathematics textbooks from Turkey, Singapore, and the international baccalaureate diploma programme

    OpenAIRE

    Sağlam, Reyhan

    2012-01-01

    Ankara : The Program of Curriculum and Instruction, Bilkent University, 2012. Thesis (Master's) -- Bilkent University, 2012. Includes bibliographical references leaves 110-118. The purpose of this study was to analyze and compare the chapters on quadratics in three mathematics textbooks selected from Turkey, Singapore, and the International Baccalaureate Diploma Programme (IBDP) in terms of content, organization, and presentation style through content analysis. The analys...

  3. Recruitment Methods and Show Rates to a Prostate Cancer Early Detection Program for High-Risk Men: A Comprehensive Analysis

    Science.gov (United States)

    Giri, Veda N.; Coups, Elliot J.; Ruth, Karen; Goplerud, Julia; Raysor, Susan; Kim, Taylor Y.; Bagden, Loretta; Mastalski, Kathleen; Zakrzewski, Debra; Leimkuhler, Suzanne; Watkins-Bruner, Deborah

    2009-01-01

    Purpose Men with a family history (FH) of prostate cancer (PCA) and African American (AA) men are at higher risk for PCA. Recruitment and retention of these high-risk men into early detection programs has been challenging. We report a comprehensive analysis on recruitment methods, show rates, and participant factors from the Prostate Cancer Risk Assessment Program (PRAP), which is a prospective, longitudinal PCA screening study. Materials and Methods Men 35–69 years are eligible if they have a FH of PCA, are AA, or have a BRCA1/2 mutation. Recruitment methods were analyzed with respect to participant demographics and show to the first PRAP appointment using standard statistical methods Results Out of 707 men recruited, 64.9% showed to the initial PRAP appointment. More individuals were recruited via radio than from referral or other methods (χ2 = 298.13, p < .0001). Men recruited via radio were more likely to be AA (p<0.001), less educated (p=0.003), not married or partnered (p=0.007), and have no FH of PCA (p<0.001). Men recruited via referrals had higher incomes (p=0.007). Men recruited via referral were more likely to attend their initial PRAP visit than those recruited by radio or other methods (χ2 = 27.08, p < .0001). Conclusions This comprehensive analysis finds that radio leads to higher recruitment of AA men with lower socioeconomic status. However, these are the high-risk men that have lower show rates for PCA screening. Targeted motivational measures need to be studied to improve show rates for PCA risk assessment for these high-risk men. PMID:19758657

  4. Mathematical and numerical analysis of hyper-elastic systems and introduction of plasticity; Analyse mathematique et numerique de systemes hyperelastiques et introduction de la plasticite

    Energy Technology Data Exchange (ETDEWEB)

    Kluth, G

    2008-12-15

    The goal is to model mathematically and numerically the dynamic phenomenons for solids in finite plasticity. We suggest a model that we call hyper-elasto-plastic based on hyper-elastic systems of conservation laws and on the use of an equation of state that we have constructed so as to achieve the plastic yield criterion of Von Mises. This model gives exact (analytic) solutions with shock split to flyer-plate experiments. The mathematical analysis of this model is done (hyperbolicity, characteristic fields, involutions and entropy). In the numerical part, we give 1D and 2D Lagrangian schemes which satisfy an entropy criterion. Moreover, thanks to a special discretization of the equations on deformation gradient, we satisfy some discrete involutions. In this work, the degeneracy of the solid model into hydrodynamic models is studied at the continuous level, and achieved at the numerical one. On different problems, we show the validity of our model and our numerical schemes. (author)

  5. Effectiveness of Computer-Assisted Mathematics Education (CAME) over Academic Achievement: A Meta-Analysis Study

    Science.gov (United States)

    Demir, Seda; Basol, Gülsah

    2014-01-01

    The aim of the current study is to determine the overall effects of Computer-Assisted Mathematics Education (CAME) on academic achievement. After an extensive review of the literature, studies using Turkish samples and observing the effects of Computer-Assisted Education (CAE) on mathematics achievement were examined. As a result of this…

  6. An Analysis of the New 9-Year Basic Education Mathematics Curriculum in Nigeria

    Science.gov (United States)

    Awofala, Adeneye O. A.

    2012-01-01

    The intention of this paper is to describe and reflect on the changes in the new 9-year basic education mathematics curriculum in Nigeria. The paper is divided into four major themes: history of curriculum development in mathematics education at the basic education level in Nigeria, the motivations for the revision of the primary and junior…

  7. Commognitive Analysis of Undergraduate Mathematics Students' First Encounter with the Subgroup Test

    Science.gov (United States)

    Ioannou, Marios

    2018-01-01

    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…

  8. The Mathematics of Networks Science: Scale-Free, Power-Law Graphs and Continuum Theoretical Analysis

    Science.gov (United States)

    Padula, Janice

    2012-01-01

    When hoping to initiate or sustain students' interest in mathematics teachers should always consider relevance, relevance to students' lives and in the middle and later years of instruction in high school and university, accessibility. A topic such as the mathematics behind networks science, more specifically scale-free graphs, is up-to-date,…

  9. Concept Map as an Assessment Tool in Secondary School Mathematics: An Analysis of Teachers' Perspectives

    Science.gov (United States)

    Mutodi, Paul; Chigonga, Benard

    2016-01-01

    This paper reports on teachers' views on concept mapping: its applicability; reliability; advantages and; difficulties. A close-ended questionnaire was administered to 50 purposefully selected secondary school mathematics teachers from Sekhukhune District, Limpopo, South Africa. The findings indicate that mathematics teachers generally perceive…

  10. A Mixed Methods Analysis of Students' Understanding of Slope and Derivative Concepts and Students' Mathematical Dispositions

    Science.gov (United States)

    Patel, Rita Manubhai

    2013-01-01

    This dissertation examined understanding of slope and derivative concepts and mathematical dispositions of first-semester college calculus students, who are recent high school graduates, transitioning to university mathematics. The present investigation extends existing research in the following ways. First, based on this investigation, the…

  11. Efficacy of the Cooperative Learning Method on Mathematics Achievement and Attitude: A Meta-Analysis Research

    Science.gov (United States)

    Capar, Gulfer; Tarim, Kamuran

    2015-01-01

    This research compiles experimental studies from 1988 to 2010 that examined the influence of the cooperative learning method, as compared with that of traditional methods, on mathematics achievement and on attitudes towards mathematics. The related field was searched using the following key words in Turkish "matematik ve isbirlikli ögrenme,…

  12. Computer-aided mathematical analysis of probability of intercept for ground-based communication intercept system

    Science.gov (United States)

    Park, Sang Chul

    1989-09-01

    We develop a mathematical analysis model to calculate the probability of intercept (POI) for the ground-based communication intercept (COMINT) system. The POI is a measure of the effectiveness of the intercept system. We define the POI as the product of the probability of detection and the probability of coincidence. The probability of detection is a measure of the receiver's capability to detect a signal in the presence of noise. The probability of coincidence is the probability that an intercept system is available, actively listening in the proper frequency band, in the right direction and at the same time that the signal is received. We investigate the behavior of the POI with respect to the observation time, the separation distance, antenna elevations, the frequency of the signal, and the receiver bandwidths. We observe that the coincidence characteristic between the receiver scanning parameters and the signal parameters is the key factor to determine the time to obtain a given POI. This model can be used to find the optimal parameter combination to maximize the POI in a given scenario. We expand this model to a multiple system. This analysis is conducted on a personal computer to provide the portability. The model is also flexible and can be easily implemented under different situations.

  13. Image analysis and mathematical modelling for the supervision of the dough fermentation process

    Science.gov (United States)

    Zettel, Viktoria; Paquet-Durand, Olivier; Hecker, Florian; Hitzmann, Bernd

    2016-10-01

    The fermentation (proof) process of dough is one of the quality-determining steps in the production of baking goods. Beside the fluffiness, whose fundaments are built during fermentation, the flavour of the final product is influenced very much during this production stage. However, until now no on-line measurement system is available, which can supervise this important process step. In this investigation the potential of an image analysis system is evaluated, that enables the determination of the volume of fermented dough pieces. The camera is moving around the fermenting pieces and collects images from the objects by means of different angles (360° range). Using image analysis algorithms the volume increase of individual dough pieces is determined. Based on a detailed mathematical description of the volume increase, which based on the Bernoulli equation, carbon dioxide production rate of yeast cells and the diffusion processes of carbon dioxide, the fermentation process is supervised. Important process parameters, like the carbon dioxide production rate of the yeast cells and the dough viscosity can be estimated just after 300 s of proofing. The mean percentage error for forecasting the further evolution of the relative volume of the dough pieces is just 2.3 %. Therefore, a forecast of the further evolution can be performed and used for fault detection.

  14. Mathematical imaging methods for mitosis analysis in live-cell phase contrast microscopy.

    Science.gov (United States)

    Grah, Joana Sarah; Harrington, Jennifer Alison; Koh, Siang Boon; Pike, Jeremy Andrew; Schreiner, Alexander; Burger, Martin; Schönlieb, Carola-Bibiane; Reichelt, Stefanie

    2017-02-15

    In this paper we propose a workflow to detect and track mitotic cells in time-lapse microscopy image sequences. In order to avoid the requirement for cell lines expressing fluorescent markers and the associated phototoxicity, phase contrast microscopy is often preferred over fluorescence microscopy in live-cell imaging. However, common specific image characteristics complicate image processing and impede use of standard methods. Nevertheless, automated analysis is desirable due to manual analysis being subjective, biased and extremely time-consuming for large data sets. Here, we present the following workflow based on mathematical imaging methods. In the first step, mitosis detection is performed by means of the circular Hough transform. The obtained circular contour subsequently serves as an initialisation for the tracking algorithm based on variational methods. It is sub-divided into two parts: in order to determine the beginning of the whole mitosis cycle, a backwards tracking procedure is performed. After that, the cell is tracked forwards in time until the end of mitosis. As a result, the average of mitosis duration and ratios of different cell fates (cell death, no division, division into two or more daughter cells) can be measured and statistics on cell morphologies can be obtained. All of the tools are featured in the user-friendly MATLAB®Graphical User Interface MitosisAnalyser. Copyright © 2017. Published by Elsevier Inc.

  15. Applied mathematics

    International Nuclear Information System (INIS)

    Nedelec, J.C.

    1988-01-01

    The 1988 progress report of the Applied Mathematics center (Polytechnic School, France), is presented. The research fields of the Center are the scientific calculus, the probabilities and statistics and the video image synthesis. The research topics developed are: the analysis of numerical methods, the mathematical analysis of the physics and mechanics fundamental models, the numerical solution of complex models related to the industrial problems, the stochastic calculus and the brownian movement, the stochastic partial differential equations, the identification of the adaptive filtering parameters, the discrete element systems, statistics, the stochastic control and the development, the image synthesis techniques for education and research programs. The published papers, the congress communications and the thesis are listed [fr

  16. Mathematical Ties That Bind.

    Science.gov (United States)

    House, Peggy A.

    1994-01-01

    Describes some mathematical investigations of the necktie which includes applications of geometry, statistics, data analysis, sampling, probability, symmetry, proportion, problem solving, and business. (MKR)

  17. Mathematical fallacies and paradoxes

    CERN Document Server

    Bunch, Bryan

    1982-01-01

    Stimulating, thought-provoking analysis of the most interesting intellectual inconsistencies in mathematics, physics, and language, including being led astray by algebra (De Morgan's paradox). 1982 edition.

  18. From root to fruit: RNA-Seq analysis shows that arbuscular mycorrhizal symbiosis may affect tomato fruit metabolism.

    Science.gov (United States)

    Zouari, Inès; Salvioli, Alessandra; Chialva, Matteo; Novero, Mara; Miozzi, Laura; Tenore, Gian Carlo; Bagnaresi, Paolo; Bonfante, Paola

    2014-03-21

    Tomato (Solanum lycopersicum) establishes a beneficial symbiosis with arbuscular mycorrhizal (AM) fungi. The formation of the mycorrhizal association in the roots leads to plant-wide modulation of gene expression. To understand the systemic effect of the fungal symbiosis on the tomato fruit, we used RNA-Seq to perform global transcriptome profiling on Moneymaker tomato fruits at the turning ripening stage. Fruits were collected at 55 days after flowering, from plants colonized with Funneliformis mosseae and from control plants, which were fertilized to avoid responses related to nutrient deficiency. Transcriptome analysis identified 712 genes that are differentially expressed in fruits from mycorrhizal and control plants. Gene Ontology (GO) enrichment analysis of these genes showed 81 overrepresented functional GO classes. Up-regulated GO classes include photosynthesis, stress response, transport, amino acid synthesis and carbohydrate metabolism functions, suggesting a general impact of fungal symbiosis on primary metabolisms and, particularly, on mineral nutrition. Down-regulated GO classes include cell wall, metabolism and ethylene response pathways. Quantitative RT-PCR validated the RNA-Seq results for 12 genes out of 14 when tested at three fruit ripening stages, mature green, breaker and turning. Quantification of fruit nutraceutical and mineral contents produced values consistent with the expression changes observed by RNA-Seq analysis. This RNA-Seq profiling produced a novel data set that explores the intersection of mycorrhization and fruit development. We found that the fruits of mycorrhizal plants show two transcriptomic "signatures": genes characteristic of a climacteric fleshy fruit, and genes characteristic of mycorrhizal status, like phosphate and sulphate transporters. Moreover, mycorrhizal plants under low nutrient conditions produce fruits with a nutrient content similar to those from non-mycorrhizal plants under high nutrient conditions

  19. Mathematics Underground

    Science.gov (United States)

    Luther, Kenneth H.

    2012-01-01

    Mathematical modeling of groundwater flow is a topic at the intersection of mathematics and geohydrology and is rarely encountered in undergraduate mathematics. However, this subject is full of interesting and meaningful examples of truly "applied" mathematics accessible to undergraduates, from the pre-calculus to advanced mathematics levels. This…

  20. Mathematical modeling, analysis and Markov Chain Monte Carlo simulation of Ebola epidemics

    Science.gov (United States)

    Tulu, Thomas Wetere; Tian, Boping; Wu, Zunyou

    Ebola virus infection is a severe infectious disease with the highest case fatality rate which become the global public health treat now. What makes the disease the worst of all is no specific effective treatment available, its dynamics is not much researched and understood. In this article a new mathematical model incorporating both vaccination and quarantine to study the dynamics of Ebola epidemic has been developed and comprehensively analyzed. The existence as well as uniqueness of the solution to the model is also verified and the basic reproduction number is calculated. Besides, stability conditions are also checked and finally simulation is done using both Euler method and one of the top ten most influential algorithm known as Markov Chain Monte Carlo (MCMC) method. Different rates of vaccination to predict the effect of vaccination on the infected individual over time and that of quarantine are discussed. The results show that quarantine and vaccination are very effective ways to control Ebola epidemic. From our study it was also seen that there is less possibility of an individual for getting Ebola virus for the second time if they survived his/her first infection. Last but not least real data has been fitted to the model, showing that it can used to predict the dynamic of Ebola epidemic.

  1. Mathematical modeling analysis of regenerative solid oxide fuel cells in switching mode conditions

    Science.gov (United States)

    Jin, Xinfang; Xue, Xingjian

    A 2D transient mathematical model is developed for regenerative solid oxide cells operated in both SOFC mode and SOEC mode. The steady state performance of the model is validated using experimental results of in-house prepared NiO-YSZ/YSZ/LSM cell under different operating temperatures. The model is employed to investigate complicated multi-physics processes during the transient process of mode switching. Simulation results indicate that the trend of internal parameter distributions, including H 2/O 2/H 2O and ionic potentials, flip when the operating cell is switched from one mode to another. However, the electronic potential shows different behaviors. At H 2 electrode, electronic potential keeps at zero voltage level, while at O 2 electrode, it increases from a relatively low level in SOFC mode to a relatively high level in SOEC mode. Transient results also show that an overshooting phenomenon occurs for mass fraction distribution of water vapor at H 2 side when the operating cell switches from SOFC mode to SOEC mode. The mass fractions of O 2 and H 2 as well as charge (electrons and ions) potentials may quickly follow the operating mode changes without over-shootings. The simulation results facilitate the internal mechanism understanding for regenerative SOFCs.

  2. Identification of children with mathematics learning disabilities (MLDs) using latent class growth analysis.

    Science.gov (United States)

    Wong, Terry T-Y; Ho, Connie S-H; Tang, Joey

    2014-11-01

    The traditional way of identifying children with mathematics learning disabilities (MLDs) using the low-achievement method with one-off assessment suffers from several limitations (e.g., arbitrary cutoff, measurement error, lacking consideration of growth). The present study attempted to identify children with MLD using the latent growth modelling approach, which minimizes the above potential problems. Two hundred and ten Chinese-speaking children were classified into five classes based on their arithmetic performance over 3 years. Their performance on various number-related cognitive measures was also assessed. A potential MLD class was identified, which demonstrated poor achievement over the 3 years and showed smaller improvement over time compared with the average-achieving class. This class had deficits in all number-related cognitive skills, hence supporting the number sense deficit hypothesis. On the other hand, another low-achieving class, which showed little improvement in arithmetic skills over time, was also identified. This class had an average cognitive profile but a low SES. Interventions should be provided to both low-achieving classes according to their needs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Systems level analysis of systemic sclerosis shows a network of immune and profibrotic pathways connected with genetic polymorphisms.

    Directory of Open Access Journals (Sweden)

    J Matthew Mahoney

    2015-01-01

    Full Text Available Systemic sclerosis (SSc is a rare systemic autoimmune disease characterized by skin and organ fibrosis. The pathogenesis of SSc and its progression are poorly understood. The SSc intrinsic gene expression subsets (inflammatory, fibroproliferative, normal-like, and limited are observed in multiple clinical cohorts of patients with SSc. Analysis of longitudinal skin biopsies suggests that a patient's subset assignment is stable over 6-12 months. Genetically, SSc is multi-factorial with many genetic risk loci for SSc generally and for specific clinical manifestations. Here we identify the genes consistently associated with the intrinsic subsets across three independent cohorts, show the relationship between these genes using a gene-gene interaction network, and place the genetic risk loci in the context of the intrinsic subsets. To identify gene expression modules common to three independent datasets from three different clinical centers, we developed a consensus clustering procedure based on mutual information of partitions, an information theory concept, and performed a meta-analysis of these genome-wide gene expression datasets. We created a gene-gene interaction network of the conserved molecular features across the intrinsic subsets and analyzed their connections with SSc-associated genetic polymorphisms. The network is composed of distinct, but interconnected, components related to interferon activation, M2 macrophages, adaptive immunity, extracellular matrix remodeling, and cell proliferation. The network shows extensive connections between the inflammatory- and fibroproliferative-specific genes. The network also shows connections between these subset-specific genes and 30 SSc-associated polymorphic genes including STAT4, BLK, IRF7, NOTCH4, PLAUR, CSK, IRAK1, and several human leukocyte antigen (HLA genes. Our analyses suggest that the gene expression changes underlying the SSc subsets may be long-lived, but mechanistically interconnected

  4. Analysis of creative mathematical thinking ability by using model eliciting activities (MEAs)

    Science.gov (United States)

    Winda, A.; Sufyani, P.; Elah, N.

    2018-05-01

    Lack of creative mathematical thinking ability can lead to not accustomed with open ended problem. Students’ creative mathematical thinking ability in the first grade at one of junior high school in Tangerang City is not fully developed. The reason of students’ creative mathematical thinking ability is not optimally developed is so related with learning process which has done by the mathematics teacher, maybe the learning design that teacher use is unsuitable for increasing students’ activity in the learning process. This research objective is to see the differences in students’ ways of answering the problems in terms of students’ creative mathematical thinking ability during the implementation of Model Eliciting Activities (MEAs). This research use post-test experimental class design. The indicators for creative mathematical thinking ability in this research arranged in three parts, as follow: (1) Fluency to answer the problems; (2) Flexibility to solve the problems; (3) Originality of answers. The result of this research found that by using the same learning model and same instrument from Model Eliciting Activities (MEAs) there are some differences in the way students answer the problems and Model Eliciting Activities (MEAs) can be one of approach used to increase students’ creative mathematical thinking ability.

  5. Navier-Stokes flow around a rotating obstacle mathematical analysis of its asymptotic behavior

    CERN Document Server

    Necasova, Sarka

    2016-01-01

    The book provides a comprehensive, detailed and self-contained treatment of the fundamental mathematical properties of problems arising from the motion of viscous incompressible fluids around rotating obstacles. It offers a new approach to this type of problems. We derive the fundamental solution of the steady case and we give pointwise estimates of velocity and its gradient (first and second one). Each chapter is preceded by a thorough discussion of the investigated problems, along with their motivation and the strategy used to solve them. The book will be useful to researchers and graduate students in mathematics, in particular mathematical fluid mechanics and differential equations.

  6. What is mathematical logic?

    CERN Document Server

    Crossley, J N; Brickhill, CJ; Stillwell, JC

    2010-01-01

    Although mathematical logic can be a formidably abstruse topic, even for mathematicians, this concise book presents the subject in a lively and approachable fashion. It deals with the very important ideas in modern mathematical logic without the detailed mathematical work required of those with a professional interest in logic.The book begins with a historical survey of the development of mathematical logic from two parallel streams: formal deduction, which originated with Aristotle, Euclid, and others; and mathematical analysis, which dates back to Archimedes in the same era. The streams beg

  7. The Development Of Mathematical Model For Automated Fingerprint Identification Systems Analysis

    International Nuclear Information System (INIS)

    Ardisasmita, M. Syamsa

    2001-01-01

    Fingerprint has a strong oriented and periodic structure composed of dark lines of raised skin (ridges) and clear lines of lowered skin (furrows)that twist to form a distinct pattern. Although the manner in which the ridges flow is distinctive, other characteristics of the fingerprint called m inutiae a re what are most unique to the individual. These features are particular patterns consisting of terminations or bifurcations of the ridges. To assert if two fingerprints are from the same finger or not, experts detect those minutiae. AFIS (Automated Fingerprint Identification Systems) extract and compare these features for determining a match. The classic methods of fingerprints recognition are not suitable for direct implementation in form of computer algorithms. The creation of a finger's model was however the necessity of development of new, better algorithms of analysis. This paper presents a new numerical methods of fingerprints' simulation based on mathematical model of arrangement of dermatoglyphics and creation of minutiae. This paper describes also the design and implementation of an automated fingerprint identification systems which operates in two stages: minutiae extraction and minutiae matching

  8. Mathematics Connection

    African Journals Online (AJOL)

    MATHEMATICS CONNECTION aims at providing a forum topromote the development of Mathematics Education in Ghana. Articles that seekto enhance the teaching and/or learning of mathematics at all levels of theeducational system are welcome.

  9. Measuring Developmental Students' Mathematics Anxiety

    Science.gov (United States)

    Ding, Yanqing

    2016-01-01

    This study conducted an item-level analysis of mathematics anxiety and examined the dimensionality of mathematics anxiety in a sample of developmental mathematics students (N = 162) by Multi-dimensional Random Coefficients Multinominal Logit Model (MRCMLM). The results indicate a moderately correlated factor structure of mathematics anxiety (r =…

  10. Teacher's Guide to Secondary Mathematics.

    Science.gov (United States)

    Duval County Schools, Jacksonville, FL.

    This is a teacher's guide to secondary school mathematics. Developed for use in the Duval County Public Schools, Jacksonville, Florida. Areas of mathematics covered are algebra, analysis, calculus, computer literacy, computer science, geometry, analytic geometry, general mathematics, consumer mathematics, pre-algebra, probability and statistics,…

  11. Associations of non-symbolic and symbolic numerical magnitude processing with mathematical competence: a meta-analysis.

    Science.gov (United States)

    Schneider, Michael; Beeres, Kassandra; Coban, Leyla; Merz, Simon; Susan Schmidt, S; Stricker, Johannes; De Smedt, Bert

    2017-05-01

    Many studies have investigated the association between numerical magnitude processing skills, as assessed by the numerical magnitude comparison task, and broader mathematical competence, e.g. counting, arithmetic, or algebra. Most correlations were positive but varied considerably in their strengths. It remains unclear whether and to what extent the strength of these associations differs systematically between non-symbolic and symbolic magnitude comparison tasks and whether age, magnitude comparison measures or mathematical competence measures are additional moderators. We investigated these questions by means of a meta-analysis. The literature search yielded 45 articles reporting 284 effect sizes found with 17,201 participants. Effect sizes were combined by means of a two-level random-effects regression model. The effect size was significantly higher for the symbolic (r = .302, 95% CI [.243, .361]) than for the non-symbolic (r = .241, 95% CI [.198, .284]) magnitude comparison task and decreased very slightly with age. The correlation was higher for solution rates and Weber fractions than for alternative measures of comparison proficiency. It was higher for mathematical competencies that rely more heavily on the processing of magnitudes (i.e. mental arithmetic and early mathematical abilities) than for others. The results support the view that magnitude processing is reliably associated with mathematical competence over the lifespan in a wide range of tasks, measures and mathematical subdomains. The association is stronger for symbolic than for non-symbolic numerical magnitude processing. So symbolic magnitude processing might be a more eligible candidate to be targeted by diagnostic screening instruments and interventions for school-aged children and for adults. © 2016 John Wiley & Sons Ltd.

  12. Expression analysis of genes associated with human osteosarcoma tumors shows correlation of RUNX2 overexpression with poor response to chemotherapy

    International Nuclear Information System (INIS)

    Sadikovic, Bekim; Thorner, Paul; Chilton-MacNeill, Susan; Martin, Jeff W; Cervigne, Nilva K; Squire, Jeremy; Zielenska, Maria

    2010-01-01

    Human osteosarcoma is the most common pediatric bone tumor. There is limited understanding of the molecular mechanisms underlying osteosarcoma oncogenesis, and a lack of good diagnostic as well as prognostic clinical markers for this disease. Recent discoveries have highlighted a potential role of a number of genes including: RECQL4, DOCK5, SPP1, RUNX2, RB1, CDKN1A, P53, IBSP, LSAMP, MYC, TNFRSF1B, BMP2, HISTH2BE, FOS, CCNB1, and CDC5L. Our objective was to assess relative expression levels of these 16 genes as potential biomarkers of osteosarcoma oncogenesis and chemotherapy response in human tumors. We performed quantitative expression analysis in a panel of 22 human osteosarcoma tumors with differential response to chemotherapy, and 5 normal human osteoblasts. RECQL4, SPP1, RUNX2, and IBSP were significantly overexpressed, and DOCK5, CDKN1A, RB1, P53, and LSAMP showed significant loss of expression relative to normal osteoblasts. In addition to being overexpressed in osteosarcoma tumor samples relative to normal osteoblasts, RUNX2 was the only gene of the 16 to show significant overexpression in tumors that had a poor response to chemotherapy relative to good responders. These data underscore the loss of tumor suppressive pathways and activation of specific oncogenic mechanisms associated with osteosarcoma oncogenesis, while drawing attention to the role of RUNX2 expression as a potential biomarker of chemotherapy failure in osteosarcoma

  13. Global morphological analysis of marine viruses shows minimal regional variation and dominance of non-tailed viruses.

    Science.gov (United States)

    Brum, Jennifer R; Schenck, Ryan O; Sullivan, Matthew B

    2013-09-01

    Viruses influence oceanic ecosystems by causing mortality of microorganisms, altering nutrient and organic matter flux via lysis and auxiliary metabolic gene expression and changing the trajectory of microbial evolution through horizontal gene transfer. Limited host range and differing genetic potential of individual virus types mean that investigations into the types of viruses that exist in the ocean and their spatial distribution throughout the world's oceans are critical to understanding the global impacts of marine viruses. Here we evaluate viral morphological characteristics (morphotype, capsid diameter and tail length) using a quantitative transmission electron microscopy (qTEM) method across six of the world's oceans and seas sampled through the Tara Oceans Expedition. Extensive experimental validation of the qTEM method shows that neither sample preservation nor preparation significantly alters natural viral morphological characteristics. The global sampling analysis demonstrated that morphological characteristics did not vary consistently with depth (surface versus deep chlorophyll maximum waters) or oceanic region. Instead, temperature, salinity and oxygen concentration, but not chlorophyll a concentration, were more explanatory in evaluating differences in viral assemblage morphological characteristics. Surprisingly, given that the majority of cultivated bacterial viruses are tailed, non-tailed viruses appear to numerically dominate the upper oceans as they comprised 51-92% of the viral particles observed. Together, these results document global marine viral morphological characteristics, show that their minimal variability is more explained by environmental conditions than geography and suggest that non-tailed viruses might represent the most ecologically important targets for future research.

  14. Marmosets, Raree shows and Pulcinelle: an Analysis and Edition of a Hitherto-Unpublished Carnival Play by Antonio de Zamora

    Directory of Open Access Journals (Sweden)

    Fernando Plata

    2013-05-01

    Full Text Available This paper is an analyisis, annotation and edition of the Mojiganga del mundinovo (‘The raree show, a carnival play’ by Antonio de Zamora. The play was performed in 1698 Madrid by the troupe of Carlos Vallejo, along with the sacramental one-act play El templo vivo de Dios (‘The living temple of God’. The hitherto unpublished text is based on the only two extant manuscripts, located in archives in Madrid. Despite the play’s title, my analysis argues that the novelty in this play is not so much the raree show, a contraption popularized four decades earlier in Golden Age theater, as the marmosets. The death of two marmosets and the ensuing desolation of their owner, Ms. Estupenda, both trigger the play and provide it with a plot. The marmosets, too, point to a changing mentality in late 17th-century society, regarding the possession among ladies of marmosets and other monkeys as pets.

  15. Cyclic Loading of Growing Tissue in a Bioreactor: Mathematical Model and Asymptotic Analysis

    KAUST Repository

    Pohlmeyer, J. V.; Cummings, L. J.

    2013-01-01

    A simplified 2D mathematical model for tissue growth within a cyclically-loaded tissue engineering scaffold is presented and analyzed. Such cyclic loading has the potential to improve yield and functionality of tissue such as bone and cartilage when

  16. New SUSYQM coherent states for Pöschl-Teller potentials: a detailed mathematical analysis

    Science.gov (United States)

    Bergeron, H.; Siegl, P.; Youssef, A.

    2012-06-01

    In a recent short note (Bergeron et al 2010 Europhys. Lett. 92 60003), we have presented the good properties of a new family of semi-classical states for Pöschl-Teller potentials. These states are built from a supersymmetric quantum mechanics (SUSYQM) approach and the parameters of these ‘coherent’ states are points in the classical phase space. In this paper, we develop all the mathematical aspects that have been left out of the previous paper (proof of the resolution of unity, detailed calculations of the quantized version of classical observables and mathematical study of the resulting operators: problems of domains, self-adjointness or self-adjoint extensions). Some additional questions such as asymptotic behavior are also studied. Moreover, the framework is extended to a larger class of Pöschl-Teller potentials. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Coherent states: mathematical and physical aspects’.

  17. Equilibrium sorption of cobalt, cesium, and strontium on Bandelier Tuff: analysis of alternative mathematical modeling

    International Nuclear Information System (INIS)

    Polzer, W.L.; Fuentes, H.R.; Essington, E.H.; Roensch, F.R.

    1985-01-01

    Sorption isotherms are derived from batch equilibrium data for cobalt, cesium and strontium on Bandelier Tuff. Experiments were conducted at an average temperature of 23 0 C and equilibrium was defined at 48 hours. The solute concentrations ranged from 0 to 500 mg/L. The radioactive isotopes 60 Co, 137 Cs, and 85 Sr were used to trace the sorption of the stable solutes. The Linear, Langmuir, Freundlich and a Modified Freundlich isotherm equations are evaluated. The Modified Freundlich isotherm equation is validated as a preferred general mathematical tool for representing the sorption of the three solutes. The empirical constants derived from the Modified Freundlich isotherm equation indicate that under dynamic flow conditions strontium will move most rapidly and cobalt least rapidly. On the other hand, chemical dispersion will be greatest for cesium and least for strontium. Hill Plots of the sorption data suggest that in the region of low saturation sorption of all three solutes is impeded by interactions among sorption sites; cobalt exhibits the greatest effect of interactions and strontium shows only a minimal effect. In the saturation region of 50% or more, sorption of cobalt is enhanced slightly by interactions among sorption sites whereas sorption of cesium and strontium appears to be independent of site interactions. 9 references, 4 figures, 2 tables

  18. Analysis Critical Thinking Stage of Eighth Grade in PBL-Scaffolding Setting To Solve Mathematical Problems

    Directory of Open Access Journals (Sweden)

    Nur Aisyah Isti

    2017-03-01

    Full Text Available The purpose of this research was described critical thinking stage of students grade VIII in setting PBL and scaffolding to solve mathematics problems. Critical thinking stage consists of clarification, assesment, inference, and strategy/tactics. The subject were teo students in the level of capacity to think critical (uncritical, less critical, quite critical, and critical. So that this research subject was 8 students in VIII A One State Junior High School of Temanggung. The result showed a description (1 critical thinking stage of students in setting PBL, in clarification the higher level of capacity to think critical students, students can identification information from question fully, can identificatio problem became detailed, and can explored the relationship among the information; (2 a strategy of scaffolding were given by critical thinking stage and TKBK, in assesment, scaffolding had given was given hint/key classically; and (3 transformation characteristic of the critical thinking stage of students after given scaffolding, it because of habituation in setting PBL and scaffolding.

  19. The nature of mathematics

    CERN Document Server

    Jourdain, Philip E B

    2007-01-01

    Anyone with an interest in mathematics will welcome the republication of this little volume by a remarkable mathematician who was also a logician, a philosopher, and an occasional writer of fiction and poetry. Originally published in 1913, and later included in the acclaimed anthology The World of Mathematics, Jourdain's survey shows how and why the methods of mathematics were developed, traces the development of mathematical science from the earliest to modern times, and chronicles the application of mathematics to natural science.Starting with the ancient Egyptians and Greeks, the author p

  20. Mathematics in ancient Greece

    CERN Document Server

    Dantzig, Tobias

    2006-01-01

    More than a history of mathematics, this lively book traces mathematical ideas and processes to their sources, stressing the methods used by the masters of the ancient world. Author Tobias Dantzig portrays the human story behind mathematics, showing how flashes of insight in the minds of certain gifted individuals helped mathematics take enormous forward strides. Dantzig demonstrates how the Greeks organized their precursors' melange of geometric maxims into an elegantly abstract deductive system. He also explains the ways in which some of the famous mathematical brainteasers of antiquity led

  1. Single Sex Mathematics Classes: A Critical Analysis of the Impact at a Secondary School

    OpenAIRE

    Seifert, Angelique; Pugalee, David K.

    2012-01-01

    Single sex classes have recently been emphasized as an effective way to promote mathematics learning. Despite their popularity, the research on the effectiveness of such programs is mixed underscoring the need for additional research and discussion. This research is set in one of the twenty-five largest public school systems in the United States, where schools have recently been allowed to begin instructional initiatives with same sex classes in mathematics. Preliminary data on the effecti...

  2. Mathematics Research in Association of Southeast Asian Nations Countries: A Scientometric Analysis of Patterns and Impacts

    Directory of Open Access Journals (Sweden)

    Thao P. Ho-Le

    2018-02-01

    Full Text Available In this study, we aimed at mapping the trend and impact of mathematics research originated from Association of Southeast Asian Nations (ASEAN countries by using a scientometric approach. We extracted the Web of Science’s article-level data of all publications concerning mathematics research during the period of 2006–2015 for ASEAN countries. The impact of research was assessed in terms of citation, and the pattern of international collaboration was mapped by the presence of coauthorship and international affiliations. During the coverage period, ASEAN countries had published 9,890 papers in mathematics, accounting for 3.8% of total ISI-indexed publications from the region. Almost 95% of the mathematics publication was from Singapore (4,107 papers, Vietnam (2,046, Malaysia (1,927, and Thailand (1,317. Approximately 54% of mathematics papers from ASEAN countries had international coauthorship, and these papers had greater yearly citation rate than those without international collaboration. With the exception of Singapore, the citation rate for other ASEAN countries was below the world average by 8–30%. The most important predictor of citations was journal impact factor, which accounted for 5.2% of total variation in citations between papers. These findings suggest that the contribution of ASEAN countries as a group to mathematics research worldwide is modest in terms of research output and impact.

  3. Mathematical Modeling of the Pituitary-Thyroid Feedback Loop: Role of a TSH-T3-Shunt and Sensitivity Analysis.

    Science.gov (United States)

    Berberich, Julian; Dietrich, Johannes W; Hoermann, Rudolf; Müller, Matthias A

    2018-01-01

    Despite significant progress in assay technology, diagnosis of functional thyroid disorders may still be a challenge, as illustrated by the vague upper limit of the reference range for serum thyrotropin ( TSH ). Diagnostical problems also apply to subjects affected by syndrome T, i.e., those 10% of hypothyroid patients who continue to suffer from poor quality of life despite normal TSH concentrations under substitution therapy with levothyroxine ( L - T 4 ). In this paper, we extend a mathematical model of the pituitary-thyroid feedback loop in order to improve the understanding of thyroid hormone homeostasis. In particular, we incorporate a TSH - T 3 -shunt inside the thyroid, whose existence has recently been demonstrated in several clinical studies. The resulting extended model shows good accordance with various clinical observations, such as a circadian rhythm in free peripheral triiodothyronine ( FT 3 ). Furthermore, we perform a sensitivity analysis of the derived model, revealing the dependence of TSH and hormone concentrations on different system parameters. The results have implications for clinical interpretation of thyroid tests, e.g., in the differential diagnosis of subclinical hypothyroidism.

  4. Mathematical Modeling of the Pituitary–Thyroid Feedback Loop: Role of a TSH-T3-Shunt and Sensitivity Analysis

    Directory of Open Access Journals (Sweden)

    Julian Berberich

    2018-03-01

    Full Text Available Despite significant progress in assay technology, diagnosis of functional thyroid disorders may still be a challenge, as illustrated by the vague upper limit of the reference range for serum thyrotropin (TSH. Diagnostical problems also apply to subjects affected by syndrome T, i.e., those 10% of hypothyroid patients who continue to suffer from poor quality of life despite normal TSH concentrations under substitution therapy with levothyroxine (L-T4. In this paper, we extend a mathematical model of the pituitary–thyroid feedback loop in order to improve the understanding of thyroid hormone homeostasis. In particular, we incorporate a TSH-T3-shunt inside the thyroid, whose existence has recently been demonstrated in several clinical studies. The resulting extended model shows good accordance with various clinical observations, such as a circadian rhythm in free peripheral triiodothyronine (FT3. Furthermore, we perform a sensitivity analysis of the derived model, revealing the dependence of TSH and hormone concentrations on different system parameters. The results have implications for clinical interpretation of thyroid tests, e.g., in the differential diagnosis of subclinical hypothyroidism.

  5. Mathematical Modeling of the Pituitary–Thyroid Feedback Loop: Role of a TSH-T3-Shunt and Sensitivity Analysis

    Science.gov (United States)

    Berberich, Julian; Dietrich, Johannes W.; Hoermann, Rudolf; Müller, Matthias A.

    2018-01-01

    Despite significant progress in assay technology, diagnosis of functional thyroid disorders may still be a challenge, as illustrated by the vague upper limit of the reference range for serum thyrotropin (TSH). Diagnostical problems also apply to subjects affected by syndrome T, i.e., those 10% of hypothyroid patients who continue to suffer from poor quality of life despite normal TSH concentrations under substitution therapy with levothyroxine (L-T4). In this paper, we extend a mathematical model of the pituitary–thyroid feedback loop in order to improve the understanding of thyroid hormone homeostasis. In particular, we incorporate a TSH-T3-shunt inside the thyroid, whose existence has recently been demonstrated in several clinical studies. The resulting extended model shows good accordance with various clinical observations, such as a circadian rhythm in free peripheral triiodothyronine (FT3). Furthermore, we perform a sensitivity analysis of the derived model, revealing the dependence of TSH and hormone concentrations on different system parameters. The results have implications for clinical interpretation of thyroid tests, e.g., in the differential diagnosis of subclinical hypothyroidism. PMID:29619006

  6. Comparative shotgun proteomic analysis of wild and domesticated Opuntia spp. species shows a metabolic adaptation through domestication.

    Science.gov (United States)

    Pichereaux, Carole; Hernández-Domínguez, Eric E; Santos-Diaz, Maria Del Socorro; Reyes-Agüero, Antonio; Astello-García, Marizel; Guéraud, Françoise; Negre-Salvayre, Anne; Schiltz, Odile; Rossignol, Michel; Barba de la Rosa, Ana Paulina

    2016-06-30

    The Opuntia genus is widely distributed in America, but the highest richness of wild species are found in Mexico, as well as the most domesticated Opuntia ficus-indica, which is the most domesticated species and an important crop in agricultural economies of arid and semiarid areas worldwide. During domestication process, the Opuntia morphological characteristics were favored, such as less and smaller spines in cladodes and less seeds in fruits, but changes at molecular level are almost unknown. To obtain more insights about the Opuntia molecular changes through domestication, a shotgun proteomic analysis and database-dependent searches by homology was carried out. >1000 protein species were identified and by using a label-free quantitation method, the Opuntia proteomes were compared in order to identify differentially accumulated proteins among wild and domesticated species. Most of the changes were observed in glucose, secondary, and 1C metabolism, which correlate with the observed protein, fiber and phenolic compounds accumulation in Opuntia cladodes. Regulatory proteins, ribosomal proteins, and proteins related with response to stress were also observed in differential accumulation. These results provide new valuable data that will help to the understanding of the molecular changes of Opuntia species through domestication. Opuntia species are well adapted to dry and warm conditions in arid and semiarid regions worldwide, and they are highly productive plants showing considerable promises as an alternative food source. However, there is a gap regarding Opuntia molecular mechanisms that enable them to grow in extreme environmental conditions and how the domestication processes has changed them. In the present study, a shotgun analysis was carried out to characterize the proteomes of five Opuntia species selected by its domestication degree. Our results will help to a better understanding of proteomic features underlying the selection and specialization under

  7. Mathematics, anxiety, and the brain.

    Science.gov (United States)

    Moustafa, Ahmed A; Tindle, Richard; Ansari, Zaheda; Doyle, Margery J; Hewedi, Doaa H; Eissa, Abeer

    2017-05-24

    Given that achievement in learning mathematics at school correlates with work and social achievements, it is important to understand the cognitive processes underlying abilities to learn mathematics efficiently as well as reasons underlying the occurrence of mathematics anxiety (i.e. feelings of tension and fear upon facing mathematical problems or numbers) among certain individuals. Over the last two decades, many studies have shown that learning mathematical and numerical concepts relies on many cognitive processes, including working memory, spatial skills, and linguistic abilities. In this review, we discuss the relationship between mathematical learning and cognitive processes as well as the neural substrates underlying successful mathematical learning and problem solving. More importantly, we also discuss the relationship between these cognitive processes, mathematics anxiety, and mathematics learning disabilities (dyscalculia). Our review shows that mathematical cognition relies on a complex brain network, and dysfunction to different segments of this network leads to varying manifestations of mathematical learning disabilities.

  8. Mathematical Footprints Discovering Mathematics Everywhere

    CERN Document Server

    Pappas, Theoni

    1999-01-01

    MATHEMATICAL FOOTPRINTS takes a creative look at the role mathematics has played since prehistoric times, and will play in the future, and uncovers mathematics where you least expect to find it from its many uses in medicine, the sciences, and its appearance in art to its patterns in nature and its central role in the development of computers. Pappas presents mathematical ideas in a readable non-threatening manner. MATHEMATICAL FOOTPRINTS is another gem by the creator of THE MATHEMATICS CALENDAR and author of THE JOY OF MATHEMATICS. "Pappas's books have been gold mines of mathematical ent

  9. Mathematics for Nonlinear Phenomena : Analysis and Computation : International Conference in honor of Professor Yoshikazu Giga on his 60th birthday

    CERN Document Server

    Jimbo, Shuichi

    2017-01-01

    This volume covers some of the most seminal research in the areas of mathematical analysis and numerical computation for nonlinear phenomena. Collected from the international conference held in honor of Professor Yoshikazu Giga’s 60th birthday, the featured research papers and survey articles discuss partial differential equations related to fluid mechanics, electromagnetism, surface diffusion, and evolving interfaces. Specific focus is placed on topics such as the solvability of the Navier-Stokes equations and the regularity, stability, and symmetry of their solutions, analysis of a living fluid, stochastic effects and numerics for Maxwell’s equations, nonlinear heat equations in critical spaces, viscosity solutions describing various kinds of interfaces, numerics for evolving interfaces, and a hyperbolic obstacle problem. Also included in this volume are an introduction of Yoshikazu Giga’s extensive academic career and a long list of his published work. Students and researchers in mathematical analy...

  10. Systems analysis of the vestibulo-ocular system. [mathematical model of vestibularly driven head and eye movements

    Science.gov (United States)

    Schmid, R. M.

    1973-01-01

    The vestibulo-ocular system is examined from the standpoint of system theory. The evolution of a mathematical model of the vestibulo-ocular system in an attempt to match more and more experimental data is followed step by step. The final model explains many characteristics of the eye movement in vestibularly induced nystagmus. The analysis of the dynamic behavior of the model at the different stages of its development is illustrated in time domain, mainly in a qualitative way.

  11. Analysis of mathematical literacy ability based on self-efficacy in model eliciting activities using metaphorical thinking approach

    Science.gov (United States)

    Setiani, C.; Waluya, S. B.; Wardono

    2018-03-01

    The purposes of this research are: (1) to identify learning quality in Model Eliciting Activities (MEAs) using a Metaphorical Thinking (MT) approach regarding qualitative and quantitative; (2) to analyze mathematical literacy of students based on Self-Efficacy (SE). This research is mixed method concurrent embedded design with qualitative research as the primary method. The quantitative research used quasi-experimental with non-equivalent control group design. The population is VIII grade students of SMP Negeri 3 Semarang Indonesia. Quantitative data is examined by conducting completeness mean test, standard completeness test, mean differentiation test and proportional differentiation test. Qualitative data is analyzed descriptively. The result of this research shows that MEAs learning using MT approach accomplishes good criteria both quantitatively and qualitatively. Students with low self-efficacy can identify problems, but they are lack ability to arrange problem-solving strategy on mathematical literacy questions. Students with medium self-efficacy can identify information provided in issues, but they find difficulties to use math symbols in making a representation. Students with high self-efficacy are excellent to represent problems into mathematical models as well as figures by using appropriate symbols and tools, so they can arrange strategy easily to solve mathematical literacy questions.

  12. Identification of cardiac rhythm features by mathematical analysis of vector fields.

    Science.gov (United States)

    Fitzgerald, Tamara N; Brooks, Dana H; Triedman, John K

    2005-01-01

    Automated techniques for locating cardiac arrhythmia features are limited, and cardiologists generally rely on isochronal maps to infer patterns in the cardiac activation sequence during an ablation procedure. Velocity vector mapping has been proposed as an alternative method to study cardiac activation in both clinical and research environments. In addition to the visual cues that vector maps can provide, vector fields can be analyzed using mathematical operators such as the divergence and curl. In the current study, conduction features were extracted from velocity vector fields computed from cardiac mapping data. The divergence was used to locate ectopic foci and wavefront collisions, and the curl to identify central obstacles in reentrant circuits. Both operators were applied to simulated rhythms created from a two-dimensional cellular automaton model, to measured data from an in situ experimental canine model, and to complex three-dimensional human cardiac mapping data sets. Analysis of simulated vector fields indicated that the divergence is useful in identifying ectopic foci, with a relatively small number of vectors and with errors of up to 30 degrees in the angle measurements. The curl was useful for identifying central obstacles in reentrant circuits, and the number of velocity vectors needed increased as the rhythm became more complex. The divergence was able to accurately identify canine in situ pacing sites, areas of breakthrough activation, and wavefront collisions. In data from human arrhythmias, the divergence reliably estimated origins of electrical activity and wavefront collisions, but the curl was less reliable at locating central obstacles in reentrant circuits, possibly due to the retrospective nature of data collection. The results indicate that the curl and divergence operators applied to velocity vector maps have the potential to add valuable information in cardiac mapping and can be used to supplement human pattern recognition.

  13. Are Clade Specific HIV Vaccines a Necessity? An Analysis Based on Mathematical Models

    Directory of Open Access Journals (Sweden)

    Dobromir Dimitrov

    2015-12-01

    Full Text Available As HIV-1 envelope immune responses are critical to vaccine related protection, most candidate HIV vaccines entering efficacy trials are based upon a clade specific design. This need for clade specific vaccine prototypes markedly reduces the implementation of potentially effective HIV vaccines. We utilized a mathematical model to determine the effectiveness of immediate roll-out of a non-clade matched vaccine with reduced efficacy compared to constructing clade specific vaccines, which would take considerable time to manufacture and test in safety and efficacy trials. We simulated the HIV epidemic in San Francisco (SF and South Africa (SA and projected effectiveness of three vaccination strategies: i immediate intervention with a 20–40% vaccine efficacy (VE non-matched vaccine, ii delayed intervention by developing a 50% VE clade-specific vaccine, and iii immediate intervention with a non-matched vaccine replaced by a clade-specific vaccine when developed. Immediate vaccination with a non-clade matched vaccine, even with reduced efficacy, would prevent thousands of new infections in SF and millions in SA over 30 years. Vaccination with 50% VE delayed for five years needs six and 12 years in SA to break-even with immediate 20 and 30% VE vaccination, respectively, while not able to surpass the impact of immediate 40% VE vaccination over 30 years. Replacing a 30% VE with a 50% VE vaccine after 5 years reduces the HIV acquisition by 5% compared to delayed vaccination. The immediate use of an HIV vaccine with reduced VE in high risk communities appears desirable over a short time line but higher VE should be the pursued to achieve strong long-term impact. Our analysis illustrates the importance of developing surrogate markers (correlates of protection to allow bridging types of immunogenicity studies to support more rapid assessment of clade specific vaccines.

  14. DISCRETE MATHEMATICS/NUMBER THEORY

    OpenAIRE

    Mrs. Manju Devi*

    2017-01-01

    Discrete mathematics is the study of mathematical structures that are fundamentally discrete rather than continuous. In contrast to real numbers that have the property of varying "smoothly", the objects studied in discrete mathematics such as integers, graphs, and statements do not vary smoothly in this way, but have distinct, separated values. Discrete mathematics therefore excludes topics in "continuous mathematics" such as calculus and analysis. Discrete objects can often be enumerated by ...

  15. Mathematics and history: history and analysis epistemology: from exhaustion method to defined integral

    Directory of Open Access Journals (Sweden)

    Mario Mandrone

    2015-06-01

    Full Text Available The creation of the calculation (differential, in the terminology of Leibniz, bending in that of Newton is the event that, in the second half of the seventeenth century, marked, in a sense, the transition from classical to modern mathematics. The aim of this work is a historical analysis of the rigor and epistemological question and the "metaphysics" of calculus that takes account of the methods of the ancient (eg. Of Archimedes' method of exhaustion, as well as interpretations of Leibniz and Newton and their successors. The problem of searching for a sure foundation on which to base the calculus, glimpsed by D'Alembert in the theory of limits and taken up by Lagrange to the theory of infinite series, and that the derivative functions, found in Cachy the pioneer of a new way to seek rigor in analysis. The Cauchy setting will be tightened by Weierstrass in the second half of the 800 with the definition of limit, with the epsilon-delta method, which in turn is based on definitions concerning the real numbers. In this sense we speak of "arithmetisation" analysis.         Matematica e storia: storia ed epistemologia dell’analisi: dal metodo  di esaustione  all’integrale  definito La creazione del calcolo (differenziale, nella terminologia leibniziana flessionale in quella di Newton è l’evento che, nella seconda metà del seicento, ha segnato, in un certo senso, il passaggio dalla matematica classica a quella moderna. Obiettivo del presente lavoro è una analisi storica ed epistemologica della questione del rigore e della “metafisica” del calcolo infinitesimale che tenga conto dei metodi degli antichi (ad es.  del metodo di esaustione di Archimede, nonché delle interpretazioni di Leibniz e Newton e dei loro successori. Il problema della ricerca di un fondamento sicuro su cui basare il calcolo infinitesimale, intravisto da D’Alembert nella teoria dei limiti e ripreso da Lagrange con la teoria delle serie infinite e quella delle

  16. The mathematics of various entertaining subjects

    CERN Document Server

    Rosenhouse, Jason

    Volume 1 : The history of mathematics is filled with major breakthroughs resulting from solutions to recreational problems. Problems of interest to gamblers led to the modern theory of probability, for example, and surreal numbers were inspired by the game of Go. Yet even with such groundbreaking findings and a wealth of popular-level books exploring puzzles and brainteasers, research in recreational mathematics has often been neglected. The Mathematics of Various Entertaining Subjects brings together authors from a variety of specialties to present fascinating problems and solutions in recreational mathematics. Contributors to the book show how sophisticated mathematics can help construct mazes that look like famous people, how the analysis of crossword puzzles has much in common with understanding epidemics, and how the theory of electrical circuits is useful in understanding the classic Towers of Hanoi puzzle. The card game SET is related to the theory of error-correcting codes, and simple tic-tac-toe tak...

  17. Design of a mathematical model for the analysis of pollutant transport in the Rio Alajuela

    International Nuclear Information System (INIS)

    Morales Mora, Martin Rodolfo

    2014-01-01

    A mathematical model is developed to analyze the transport of pollutants over time and mainstem of the Rio Alajuela. The environmental resilience thereof is assessed and the physical and morphological characteristics of its basin. The basin hydrological information is obtained from the record 842418 flow station, Alajuela. A spatial distribution of the flow is generated along the entire channel of the Rio Alajuela. The hydraulic and environmental parameters are estimated based on four discharge curves created from information of the four points of capacity used by the Centro de Investigacion en Desarrollo Sostenible (CIEDES) on work done during the year 2012 in the Rio Alajuela. The numerical model developed has used the one-dimensional advection-dispersion equation with reaction, in which the derivatives were transformed into finite differences through the use of an explicit scheme called: Aguas Arriba. The upstream model used by the CIEDES is applied to the Rio Alajuela. The information of the flows is taken into account together with the estimated coefficients of dispersion and reaction, generating five different scenarios in which it is assessed the resilience of the river. The results have showed that the resilience to pollution by discharges of domestic wastewater of the Rio Alajuela is zero, also it has carried pollution into the lower parts. The intervention of the Municipalidad de Alajuela is recommended for control of illegal discharges into the river. The construction of infrastructure has been for the improvement of domestic wastewater, especially in the middle of the basin by high urban concentration that has generated to be the zone with greater pollution. (author) [es

  18. Evolution Analysis of the Aux/IAA Gene Family in Plants Shows Dual Origins and Variable Nuclear Localization Signals

    Directory of Open Access Journals (Sweden)

    Wentao Wu

    2017-10-01

    Full Text Available The plant hormone auxin plays pivotal roles in many aspects of plant growth and development. The auxin/indole-3-acetic acid (Aux/IAA gene family encodes short-lived nuclear proteins acting on auxin perception and signaling, but the evolutionary history of this gene family remains to be elucidated. In this study, the Aux/IAA gene family in 17 plant species covering all major lineages of plants is identified and analyzed by using multiple bioinformatics methods. A total of 434 Aux/IAA genes was found among these plant species, and the gene copy number ranges from three (Physcomitrella patens to 63 (Glycine max. The phylogenetic analysis shows that the canonical Aux/IAA proteins can be generally divided into five major clades, and the origin of Aux/IAA proteins could be traced back to the common ancestor of land plants and green algae. Many truncated Aux/IAA proteins were found, and some of these truncated Aux/IAA proteins may be generated from the C-terminal truncation of auxin response factor (ARF proteins. Our results indicate that tandem and segmental duplications play dominant roles for the expansion of the Aux/IAA gene family mainly under purifying selection. The putative nuclear localization signals (NLSs in Aux/IAA proteins are conservative, and two kinds of new primordial bipartite NLSs in P. patens and Selaginella moellendorffii were discovered. Our findings not only give insights into the origin and expansion of the Aux/IAA gene family, but also provide a basis for understanding their functions during the course of evolution.

  19. Evolution Analysis of the Aux/IAA Gene Family in Plants Shows Dual Origins and Variable Nuclear Localization Signals.

    Science.gov (United States)

    Wu, Wentao; Liu, Yaxue; Wang, Yuqian; Li, Huimin; Liu, Jiaxi; Tan, Jiaxin; He, Jiadai; Bai, Jingwen; Ma, Haoli

    2017-10-08

    The plant hormone auxin plays pivotal roles in many aspects of plant growth and development. The auxin/indole-3-acetic acid (Aux/IAA) gene family encodes short-lived nuclear proteins acting on auxin perception and signaling, but the evolutionary history of this gene family remains to be elucidated. In this study, the Aux/IAA gene family in 17 plant species covering all major lineages of plants is identified and analyzed by using multiple bioinformatics methods. A total of 434 Aux/IAA genes was found among these plant species, and the gene copy number ranges from three ( Physcomitrella patens ) to 63 ( Glycine max ). The phylogenetic analysis shows that the canonical Aux/IAA proteins can be generally divided into five major clades, and the origin of Aux/IAA proteins could be traced back to the common ancestor of land plants and green algae. Many truncated Aux/IAA proteins were found, and some of these truncated Aux/IAA proteins may be generated from the C-terminal truncation of auxin response factor (ARF) proteins. Our results indicate that tandem and segmental duplications play dominant roles for the expansion of the Aux/IAA gene family mainly under purifying selection. The putative nuclear localization signals (NLSs) in Aux/IAA proteins are conservative, and two kinds of new primordial bipartite NLSs in P. patens and Selaginella moellendorffii were discovered. Our findings not only give insights into the origin and expansion of the Aux/IAA gene family, but also provide a basis for understanding their functions during the course of evolution.

  20. Performance analysis on free-piston Stirling cryocooler based on an idealized mathematical model

    Science.gov (United States)

    Guo, Y. X.; Chao, Y. J.; Gan, Z. H.; Li, S. Z.; Wang, B.

    2017-12-01

    Free-piston Stirling cryocoolers have extensive applications for its simplicity in structure and decrease in mass. However, the elimination of the motor and the crankshaft has made its thermodynamic characteristic different from that of Stirling cryocoolers with displacer driving mechanism. Therefore, an idealized mathematical model has been established, and with this model, an attempt has been made to analyse the thermodynamic characteristic and the performance of free-piston Stirling cryocooler. To certify this mathematical model, a comparison has been made between the model and a numerical model. This study reveals that due to the displacer damping force necessary for the production of cooling capacity, the free-piston Stirling cryocooler is inherently less efficient than Stirling cryocooler with displacer driving mechanism. Viscous flow resistance and incomplete heat transfer in the regenerator are the two major causes of the discrepancy between the results of the idealized mathematical model and the numerical model.

  1. Numerical Analysis of Forth-Order Boundary Value Problems in Fluid Mechanics and Mathematics

    DEFF Research Database (Denmark)

    Hosseinzadeh, E.; Barari, Amin; Fouladi, F.

    2011-01-01

    In this paper He's variational iteration method is used to solve some examples of linear and non-linear forth-order boundary value problems. The first problem compared with homotopy analysis method solution and the other ones with the exact solution. The results show the high accuracy and speed o...

  2. Numerical analysis of fourth-order boundary value problems in fluid mechanics and mathematics

    DEFF Research Database (Denmark)

    Hosseinzadeh, Elham; Barari, Amin; Fouladi, Fama

    2010-01-01

    In this paper He's variational iteration method is used to solve some examples of linear and non-linear forth-order boundary value problems. The first problem compared with homotopy analysis method solution and the other ones with the exact solution. The results show the high accuracy and speed o...

  3. Exploring the impact of learning objects in middle school mathematics and science classrooms: A formative analysis

    Directory of Open Access Journals (Sweden)

    Robin H. Kay

    2008-12-01

    Full Text Available The current study offers a formative analysis of the impact of learning objects in middle school mathematics and science classrooms. Five reliable and valid measure of effectiveness were used to examine the impact of learning objects from the perspective of 262 students and 8 teachers (14 classrooms in science or mathematics. The results indicate that teachers typically spend 1-2 hours finding and preparing for learning-object based lesson plans that focus on the review of previous concepts. Both teachers and students are positive about the learning benefits, quality, and engagement value of learning objects, although teachers are more positive than students. Student performance increased significantly, over 40%, when learning objects were used in conjunction with a variety of teaching strategies. It is reasonable to conclude that learning objects have potential as a teaching tool in a middle school environment. L’impacte des objets d’apprentissage dans les classes de mathématique et de sciences à l’école intermédiaire : une analyse formative Résumé : Cette étude présente une analyse formative de l’impacte des objets d’apprentissage dans les classes de mathématique et de sciences à l’école intermédiaire. Cinq mesures de rendement fiables et valides ont été exploitées pour examiner l’effet des objets d’apprentissage selon 262 élèves et 8 enseignants (414 classes en science ou mathématiques. Les résultats indiquent que les enseignants passent typiquement 1-2 heures pour trouver des objets d’apprentissage et préparer les leçons associées qui seraient centrées sur la revue de concepts déjà vus en classe. Quoique les enseignants aient répondu de façon plus positive que les élèves, les deux groupes ont répondu positivement quant aux avantages au niveau de l’apprentissage, à la qualité ainsi qu’à la valeur motivationnelle des objets d’apprentissage. Le rendement des élèves aurait aussi augment

  4. An exploration of preservice teachers’ educational values of mathematics in relation to gender and attitudes toward mathematics in Nigeria

    Directory of Open Access Journals (Sweden)

    Adeneye Olarewaju Awofala

    2018-04-01

    Full Text Available The study investigated educational values of mathematics in relation to gender and attitudes toward mathematics among 480 Nigerian preservice mathematics teachers from four universities in Southwest, Nigeria using the quantitative research method within the blueprint of the descriptive survey design. Data collected were analysed using the descriptive statistics of frequency, percentage, mean, and standard deviation and inferential statistics of independent samples t-test, Pearson moment correlation, and multiple regression analysis. Findings revealed that preservice mathematics teachers showed high level of educational value of mathematics. There were significant possible correlations among preservice mathematics teachers’ practical value, aesthetic value, cultural value, social value, moral value, disciplinary value, recreational value, and attitudes toward mathematics. While gender differences in some dimensions of educational value of mathematics (practical value, disciplinary value, social value, and cultural value are no longer important and are declining there are subtle gender differences in attitudes toward mathematics and educational values of mathematics in this study. In addition, 73.7% of the variance in preservice teachers’ attitudes toward mathematics was accounted for by the eight predictor variables (gender, practical or utilitarian value, disciplinary value, cultural value, social value, moral value, aesthetic value and recreational value taken together. Based on this baseline study, it was thus, recommended that future studies in Nigeria should investigate the educational value of mathematics of in-service teachers with varied ethnicity and socio-economic background so as to generalise the results of this study.

  5. Analysis of a Mathematical Model of Lithium-Sulfur Cells Part III: Electrochemical Reaction Kinetics, Transport Properties and Charging

    International Nuclear Information System (INIS)

    Ghaznavi, Mahmoudreza; Chen, P.

    2014-01-01

    Highlights: • The discharge behavior of Li-S cells in wide range of exchange current densities of electrochemical reactions is studied. • Among all reduction reactions, 1/2 S 8(l) +e − ⇌1/2 S 8 2− and 1/2 S 2 2− +e − ⇌2S 2− play the most important role in capacity performance. • Low diffusion increases the precipitation of polysulfides in separator which may block the anode surface. • Large solubility of Li 2 S is needed for the model to be able to simulate the charging process. - Abstract: Sensitivity analysis of a mathematical model of a lithium-sulfur (Li-S) battery was performed by investigating the response of the model to variation of the exchange current densities, diffusion coefficients, and cathode thickness over a wide range; the results of the analysis were used to explain the some aspects of the behavior of the system which may be seen in experiments. In particular, among all the exchange current densities, the exchange current density of the elemental sulfur reduction has the most significant effect on the discharge capacity of the cell. The variation of the diffusion coefficients was also analyzed, providing information on the non-uniformity of precipitants in the cell after discharge. An optimum cathode thickness was presented to gain the highest capacity of the cell. Finally, the simulation of charging was studied, showing that the model needs a large solubility product of di-lithium sulfide to be able to simulate the charge process of a cell

  6. Mathematical intuitionism

    CERN Document Server

    Dragalin, A G

    1988-01-01

    This monograph is intended to present the most important methods of proof theory in intuitionistic logic, assuming the reader to have mastered an introductory course in mathematical logic. The book starts with purely syntactical methods based on Gentzen's cut-elimination theorem, followed by intuitionistic arithmetic where Kleene's realizability method plays a central role. The author then studies algebraic models and completeness theorems for them. After giving a survey on the principles of intuitionistic analysis, the last part of the book presents the cut-elimination theorem in intuitionistic simple theory of types with an extensionality rule.

  7. Mathematical foundation of the application of modal analysis to the investigation of space-time reactor behaviour

    International Nuclear Information System (INIS)

    Obradovic, D.M.

    1970-01-01

    In recent years investigations in the field of kinetics and dynamics of nuclear reactors have been directed towards overcoming an insufficiently accurate point reactor model. For that purpose different mathematical approaches have been used. This thesis is devoted to modal analysis because, from the practical point of view, it is a very promising and, from the mathematical and physical point of view, a very interesting method. Some fundamental mathematical problems connected with the application of modal analysis to the investigations of the reactor space-time behaviour are still unsolved and accordingly our purpose is to solve some of these problems. The spectral properties of the diffusion and P 1 operators are studied in some detail applying the Krein-Rutman theory of the K-positive operators, the Krasnosel'skii theory of u 0 operators, and the Keldis theory of the operator families. The formal solution to the initial value problem (as an abstract Cauchy problem), associated with the diffusion and P 1 operators is also studied. Modal analysis is identified as a set of methods in the mathematical literature known as the Galerkin methods (or projection methods). Following this idea (using the results of the mathematical investigations of the Galerkin methods) and using our results of the investigations of the properties of the diffusion and P 1 operators, the applicability of modal analysis to the approximate solution of the diffusion and P 1 equations and of the eigenvalue problems associated with the diffusion and P 1 operators is established. As an example of the application of modal analysis the Bubnov and Galerkin method is applied to a multiregion thermal nuclear reactor for the determination of: (i) frequency response, (ii) eigenvalues and eigenvectors of the stationary diffusion operator, (iii) eigenvalues and eigenvectors of the non-stationary diffusion operators. On the basis of the expressions obtained the corresponding computer programmes for radial

  8. Mathematical Problem Solving Ability of Junior High School Students through Ang’s Framework for Mathematical Modelling Instruction

    Science.gov (United States)

    Fasni, N.; Turmudi, T.; Kusnandi, K.

    2017-09-01

    This research background of this research is the importance of student problem solving abilities. The purpose of this study is to find out whether there are differences in the ability to solve mathematical problems between students who have learned mathematics using Ang’s Framework for Mathematical Modelling Instruction (AFFMMI) and students who have learned using scientific approach (SA). The method used in this research is a quasi-experimental method with pretest-postest control group design. Data analysis of mathematical problem solving ability using Indepent Sample Test. The results showed that there was a difference in the ability to solve mathematical problems between students who received learning with Ang’s Framework for Mathematical Modelling Instruction and students who received learning with a scientific approach. AFFMMI focuses on mathematical modeling. This modeling allows students to solve problems. The use of AFFMMI is able to improve the solving ability.

  9. EXPERIENCE OF THE REMOTE COURSE IMPLEMENTATION FOR THE ORGANIZATION OF THE INDEPENDENT WORK OF STUDENTS FROM MATHEMATICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Botuzova Y.

    2017-12-01

    Full Text Available The article raises the problem of organization independent work of students. In particular, the model of integration of traditional and distance learning in the form of a blended learning is considered. The experience of introducing a distance course in the discipline "Mathematical Analysis" is described. The purpose of this distance course is the effective organization of independent out of class work of future mathematics teachers. In this paper, the structure of educational and methodological support of the educational process on mathematical analysis is examined, as well as its model in a blended learning is presented. The didactic capabilities of distance technologies are analyzed. The step-by-step scheme of organization of independent work of students in the context of the use of distance course is offered. The scheme consists of the following stages: preparatory, theoretical, practical-activity, controlling, corrective. The author describes in detail the contents of the work of the teacher and students at each of these stages. The peculiarities of planning, developing and implementing a distance course, and the leadership of independent work of students are revealed. For this, the teacher performs the following functions: the formation of a permanent positive student motivation; defining and setting goals and objectives; organization of interaction between students; control and counseling of students in the learning process. A number of psychological and pedagogical problems are highlighted in the implementation of the distance learning form and the ways of their partial or complete elimination are indicated.

  10. Derivation and application of mathematical model for well test analysis with variable skin factor in hydrocarbon reservoirs

    Directory of Open Access Journals (Sweden)

    Pengcheng Liu

    2016-06-01

    Full Text Available Skin factor is often regarded as a constant in most of the mathematical model for well test analysis in oilfields, but this is only a kind of simplified treatment with the actual skin factor changeable. This paper defined the average permeability of a damaged area as a function of time by using the definition of skin factor. Therefore a relationship between a variable skin factor and time was established. The variable skin factor derived was introduced into existing traditional models rather than using a constant skin factor, then, this newly derived mathematical model for well test analysis considering variable skin factor was solved by Laplace transform. The dimensionless wellbore pressure and its derivative changed with dimensionless time were plotted with double logarithm and these plots can be used for type curve fitting. The effects of all the parameters in the expression of variable skin factor were analyzed based on the dimensionless wellbore pressure and its derivative. Finally, actual well testing data were used to fit the type curves developed which validates the applicability of the mathematical model from Sheng-2 Block, Shengli Oilfield, China.

  11. Mathematical Model and Computational Analysis of Selected Transient States of Cylindrical Linear Induction Motor Fed via Frequency Converter

    Directory of Open Access Journals (Sweden)

    Andrzej Rusek

    2008-01-01

    Full Text Available The mathematical model of cylindrical linear induction motor (C-LIM fed via frequency converter is presented in the paper. The model was developed in order to analyze numerically the transient states. Problems concerning dynamics of ac-machines especially linear induction motor are presented in [1 – 7]. Development of C-LIM mathematical model is based on circuit method and analogy to rotary induction motor. The analogy between both: (a stator and rotor windings of rotary induction motor and (b winding of primary part of C-LIM (inductor and closed current circuits in external secondary part of C-LIM (race is taken into consideration. The equations of C-LIM mathematical model are presented as matrix together with equations expressing each vector separately. A computational analysis of selected transient states of C-LIM fed via frequency converter is presented in the paper. Two typical examples of C-LIM operation are considered for the analysis: (a starting the motor at various static loads and various synchronous velocities and (b reverse of the motor at the same operation conditions. Results of simulation are presented as transient responses including transient electromagnetic force, transient linear velocity and transient phase current.

  12. Race, Ideology, and Academic Ability: A Relational Analysis of Racial Narratives in Mathematics

    Science.gov (United States)

    Shah, Niral

    2017-01-01

    Background/Context: There is evidence that race affects students' learning experiences in mathematics, a subject typically thought of as "race-neutral" and "culture-free." Research in psychology and sociology has shown that racial narratives (e.g., "Asians are good at math") are pervasive in U.S. culture and play a…

  13. Mathematical modeling analysis of intratumoral disposition of anticancer agents and drug delivery systems.

    Science.gov (United States)

    Popilski, Hen; Stepensky, David

    2015-05-01

    Solid tumors are characterized by complex morphology. Numerous factors relating to the composition of the cells and tumor stroma, vascularization and drainage of fluids affect the local microenvironment within a specific location inside the tumor. As a result, the intratumoral drug/drug delivery system (DDS) disposition following systemic or local administration is non-homogeneous and its complexity reflects the differences in the local microenvironment. Mathematical models can be used to analyze the intratumoral drug/DDS disposition and pharmacological effects and to assist in choice of optimal anticancer treatment strategies. The mathematical models that have been applied by different research groups to describe the intratumoral disposition of anticancer drugs/DDSs are summarized in this article. The properties of these models and of their suitability for prediction of the drug/DDS intratumoral disposition and pharmacological effects are reviewed. Currently available mathematical models appear to neglect some of the major factors that govern the drug/DDS intratumoral disposition, and apparently possess limited prediction capabilities. More sophisticated and detailed mathematical models and their extensive validation are needed for reliable prediction of different treatment scenarios and for optimization of drug treatment in the individual cancer patients.

  14. A review of mathematical functions for the analysis of growth in poultry

    NARCIS (Netherlands)

    Darmani Kuhi, H.; Porter, T.; Lopez, S.; Kebreab, E.; Strathe, A.B.; Dumas, A.; Dijkstra, J.; France, J.

    2010-01-01

    Poultry industries face various decisions in the production cycle that affect the profitability of an operation. Predictions of growth when the birds are ready for sale are important factors that contribute to the economy of poultry operations. Mathematical functions called ‘growth functions’ have

  15. The Answering Process for Multiple-Choice Questions in Collaborative Learning: A Mathematical Learning Model Analysis

    Science.gov (United States)

    Nakamura, Yasuyuki; Nishi, Shinnosuke; Muramatsu, Yuta; Yasutake, Koichi; Yamakawa, Osamu; Tagawa, Takahiro

    2014-01-01

    In this paper, we introduce a mathematical model for collaborative learning and the answering process for multiple-choice questions. The collaborative learning model is inspired by the Ising spin model and the model for answering multiple-choice questions is based on their difficulty level. An intensive simulation study predicts the possibility of…

  16. What Were You Thinking? A Deleuzian/Guattarian Analysis of Communication in the Mathematics Classroom

    Science.gov (United States)

    de Freitas, Elizabeth

    2013-01-01

    The primary aim of this article is to bring the work of Deleuze and Guattari to bear on the question of communication in the classroom. I focus on the mathematics classroom, where agency and subjectivity are highly regulated by the rituals of the discipline, and where neoliberal psychological frameworks continue to dominate theories of teaching…

  17. Mathematical-statistical model for analysis of Ulva algal net photosynthesis in Venice lagoon

    International Nuclear Information System (INIS)

    Izzo, G.; Rizzo, V.; Bella, A.; Picci, M.; Giordano, P.

    1996-08-01

    The algal net photosynthesis, an important factor for the characterization of water quality in Venice lagoon, has been studied experimentally providing a mathematical model, validated by using statistical methods. This model relates oxygen production with irradiance, according to a well known law in biological literature. Its observed an inverted proportion between algal oxygen production and temperature, thus seasonality

  18. New SUSYQM coherent states for Pöschl–Teller potentials: a detailed mathematical analysis

    International Nuclear Information System (INIS)

    Bergeron, H; Siegl, P; Youssef, A

    2012-01-01

    In a recent short note (Bergeron et al 2010 Europhys. Lett. 92 60003), we have presented the good properties of a new family of semi-classical states for Pöschl–Teller potentials. These states are built from a supersymmetric quantum mechanics (SUSYQM) approach and the parameters of these ‘coherent’ states are points in the classical phase space. In this paper, we develop all the mathematical aspects that have been left out of the previous paper (proof of the resolution of unity, detailed calculations of the quantized version of classical observables and mathematical study of the resulting operators: problems of domains, self-adjointness or self-adjoint extensions). Some additional questions such as asymptotic behavior are also studied. Moreover, the framework is extended to a larger class of Pöschl–Teller potentials. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Coherent states: mathematical and physical aspects’. (paper)

  19. An Examination in Turkey: Error Analysis of Mathematics Students on Group Theory

    Science.gov (United States)

    Arikan, Elif Esra; Ozkan, Ayten; Ozkan, E. Mehmet

    2015-01-01

    The aim of this study is to analyze the mistakes that have been made in the group theory underlying the algebra mathematics. The 100 students taking algebra math 1 class and studying at the 2nd grade at a state university in Istanbul participated in this study. The related findings were prepared as a classical exam of 6 questions which have been…

  20. Mathematical analysis of fluids in motion: from well-posedness to model reduction

    Czech Academy of Sciences Publication Activity Database

    Feireisl, Eduard

    2013-01-01

    Roč. 26, č. 2 (2013), s. 299-340 ISSN 1139-1138 Keywords : Navier-Stokes-Fourier system * compressible fluid * singular limits Subject RIV: BA - General Mathematics Impact factor: 0.585, year: 2013 http://link.springer.com/article/10.1007/s13163-013-0126-2

  1. Gender Differences in Mathematics Achievement in Jordan: A Differential Item Functioning Analysis of the 2015 TIMSS

    Science.gov (United States)

    Innabi, Hanan; Dodeen, Hamzeh

    2018-01-01

    This study is within the framework of the United Nations sustainable development goals related to equitable quality education. The total score on the 2015 Trends in International Mathematics and Science Study that indicated eighth-grade girls in Jordan significantly outperformed boys is hiding many details related to the quality of mathematics…

  2. Emotions, Self-Regulated Learning, and Achievement in Mathematics: A Growth Curve Analysis

    Science.gov (United States)

    Ahmed, Wondimu; van der Werf, Greetje; Kuyper, Hans; Minnaert, Alexander

    2013-01-01

    The purpose of the current study was twofold: (a) to investigate the developmental trends of 4 academic emotions (anxiety, boredom, enjoyment, and pride) and (b) to examine whether changes in emotions are linked to the changes in students' self-regulatory strategies (shallow, deep, and meta-cognitive) and achievement in mathematics. Four hundred…

  3. MATHEMATIC MODELING IN ANALYSIS OF BIO-GAS PURIFICATION FROM CARBON DIOXIDE

    Directory of Open Access Journals (Sweden)

    Y. A. Losiouk

    2009-01-01

    Full Text Available The paper considers a possibility to involve bio-gas generated at testing grounds of hard domestic garbage in power supply system in the Republic of Belarus. An example of optimization using mathematical modeling of plant operation which is used for bio-gas enrichment is given in the paper. 

  4. Assessment of the Assessment Tool: Analysis of Items in a Non-MCQ Mathematics Exam

    Science.gov (United States)

    Khoshaim, Heba Bakr; Rashid, Saima

    2016-01-01

    Assessment is one of the vital steps in the teaching and learning process. The reported action research examines the effectiveness of an assessment process and inspects the validity of exam questions used for the assessment purpose. The instructors of a college-level mathematics course studied questions used in the final exams during the academic…

  5. An Analysis of Mathematics Teacher Candidates' Critical Thinking Dispositions and Their Logical Thinking Skills

    Science.gov (United States)

    Incikabi, Lutfi; Tuna, Abdulkadir; Biber, Abdullah Cagri

    2013-01-01

    This study aimed to investigate the existence of the relationship between mathematics teacher candidates' critical thinking skills and their logical thinking dispositions in terms of the variables of grade level in college, high school type, and gender. The current study utilized relational survey model and included a total of 99 mathematics…

  6. Analysis of Self-Directed Learning upon Student of Mathematics Education Study Program

    Science.gov (United States)

    Kleden, Maria Agustina

    2015-01-01

    Various studies have rendered self-directed learning disposition to be significant in the learning of mathematics, however several previous studies have pointed the level of self-directed learning disposition to be at a low point. This research is aimed to enhance self-directed learning through implementing a metacognitive strategy in learning…

  7. Summary of research in applied mathematics, numerical analysis and computer science at the Institute for Computer Applications in Science and Engineering

    Science.gov (United States)

    1984-01-01

    Research conducted at the Institute for Computer Applications in Science and Engineering in applied mathematics, numerical analysis and computer science during the period October 1, 1983 through March 31, 1984 is summarized.

  8. Summary of research conducted at the Institute for Computer Applications in Science and Engineering in applied mathematics, numerical analysis and computer science

    Science.gov (United States)

    1989-01-01

    Research conducted at the Institute for Computer Applications in Science and Engineering in applied mathematics, numerical analysis, and computer science during the period October 1, 1988 through March 31, 1989 is summarized.

  9. Introductory mathematics for earth scientists

    CERN Document Server

    Yang, Xin-She

    2009-01-01

    Any quantitative work in earth sciences requires mathematical analysis and mathematical methods are essential to the modelling and analysis of the geological, geophysical and environmental processes involved. This book provides an introduction to the fundamental mathematics that all earth scientists need.

  10. Relationship of Mathematics Olympiad Performance of Gifted Students with IQ and Mathematics Achievement

    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.

  11. Kinetics of hydrogen peroxide elimination by astrocytes and C6 glioma cells analysis based on a mathematical model.

    Science.gov (United States)

    Makino, Nobuo; Mise, Takeshi; Sagara, Jun-Ichi

    2008-06-01

    Oxidative stress is implicated in a variety of disorders including neurodegenerative diseases, and H(2)O(2) is important in the generation of reactive oxygen and oxidative stress. In this study, we have examined the rate of extracellular H(2)O(2) elimination and relevant enzyme activities in cultured astrocytes and C6 glioma cells and have analyzed the results based on a mathematical model. As compared with other types of cultured cells, astrocytes showed higher activity of glutathione peroxidase (GPx) but lower activities for GSH recycling. C6 cells showed relatively low GPx activity, and treatment of C6 cells with dibutyryl-cAMP, which induces astrocytic differentiation, increased catalase activity and H(2)O(2) permeation rate but exerted little effect on other enzyme activities. A mathematical model [N. Makino, K. Sasaki, N. Hashida, Y. Sakakura, A metabolic model describing the H(2)O(2) elimination by mammalian cells including H(2)O(2) permeation through cytoplasmic and peroxisomal membranes: comparison with experimental data, Biochim. Biophys. Acta 1673 (2004) 149-159.], which includes relevant enzymes and H(2)O(2) permeation through membranes, was found to be fitted well to the H(2)O(2) concentration dependences of removal reaction with the permeation rate constants as variable parameters. As compared with PC12 cells as a culture model for neuron, H(2)O(2) removal activity of astrocytes was considerably higher at physiological H(2)O(2) concentrations. The details of the mathematical model are presented in Appendix.

  12. Attitudes of university precalculus students toward mathematics.

    Science.gov (United States)

    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.

  13. Philosophy and mathematics: interactions.

    Science.gov (United States)

    Rashed, Roshdi

    From Plato to the beginnings of the last century, mathematics provided philosophers with methods of exposition, procedures of demonstration, and instruments of analysis. The unprecedented development of mathematics on the one hand, and the mathematicians' appropriation of Logic from the philosophers on the other hand, have given rise to two problems with which the philosophers have to contend: (1) Is there still a place for the philosophy of mathematics? and (2) To what extent is a philosophy of mathematics still possible? This article offers some reflections on these questions, which have preoccupied a good many philosophers and continue to do so.

  14. IMPROVING TEACHING MATHEMATICS USING MODERN INFORMATION TECHNOLOGIES IN FORMATION MATHEMATICAL COMPETENCE REQUIRED FUTURE SKIPPERS.

    Directory of Open Access Journals (Sweden)

    Elena Gudyreva

    2015-10-01

    Full Text Available The article is devoted to consideration of issues related to identifying the potential for teaching mathematics using network (Internet technology and the introduction of elements of distance learning into educational process of higher educational establishments of the sea profile, as well as achievement of formation of mathematical competence of students of the University generally, and of the University's Maritime profile, in particular. Based on the analysis of psychological and pedagogical literature highlights the factors that influence the increase of efficiency of independent work of students of higher educational institutions and on the formation of steady skills of self-education that ultimately leads to quality of formation of mathematical competence of a student. Specific features of teaching mathematics at the University of the sea profile. The description of the project (complex sites "KSMA. Higher mathematics navigators", who developed and used in the Kherson state Maritime Academy in the teaching of mathematics and the organization of individual techniques of distance learning, shows the simplicity and accessibility of working with complex sites, as well as the simplicity and accessibility of design "personal website", but in fact complex sites, by a teacher of any discipline of higher education. Shown, also a training process with the use of the project "KSMA. Higher mathematics navigators", analyzes the experience of teaching the course "Higher mathematics" in a higher educational institution of the marine profile with the use of a personal website, a teacher and shown positive results in students mastery of basic mathematical competencies.

  15. Open problems in mathematics

    CERN Document Server

    Nash, Jr, John Forbes

    2016-01-01

    The goal in putting together this unique compilation was to present the current status of the solutions to some of the most essential open problems in pure and applied mathematics. Emphasis is also given to problems in interdisciplinary research for which mathematics plays a key role. This volume comprises highly selected contributions by some of the most eminent mathematicians in the international mathematical community on longstanding problems in very active domains of mathematical research. A joint preface by the two volume editors is followed by a personal farewell to John F. Nash, Jr. written by Michael Th. Rassias. An introduction by Mikhail Gromov highlights some of Nash’s legendary mathematical achievements. The treatment in this book includes open problems in the following fields: algebraic geometry, number theory, analysis, discrete mathematics, PDEs, differential geometry, topology, K-theory, game theory, fluid mechanics, dynamical systems and ergodic theory, cryptography, theoretical computer sc...

  16. The relation between early constructive play and mathematical word problem solving is mediated by spatial ability. A path analysis in sixth grade students.

    NARCIS (Netherlands)

    Oostermeijer, M.; Boonen, A.J.H.; Jolles, J.

    2014-01-01

    The scientific literature shows that constructive play activities are positively related to children's spatial ability. Likewise, a close positive relation is found between spatial ability and mathematical word problem-solving performances. The relation between children's constructive play and their

  17. Mathematics disorder

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001534.htm Mathematics disorder To use the sharing features on this page, please enable JavaScript. Mathematics disorder is a condition in which a child's ...

  18. Teaching secondary mathematics

    CERN Document Server

    Rock, David

    2013-01-01

    Solidly grounded in up-to-date research, theory and technology,?Teaching Secondary Mathematics?is a practical, student-friendly, and popular text for secondary mathematics methods courses. It provides clear and useful approaches for mathematics teachers, and shows how concepts typically found in a secondary mathematics curriculum can be taught in a positive and encouraging way. The thoroughly revised fourth edition combines this pragmatic approach with truly innovative and integrated technology content throughout. Synthesized content between the book and comprehensive companion websi

  19. A Critical Discourse Analysis of Practical Problems in a Foundation Mathematics Course at a South African University

    Science.gov (United States)

    le Roux, Kate; Adler, Jill

    2016-01-01

    Mathematical problems that make links to the everyday and to disciplines other than mathematics--variously referred to as practical, realistic, real-world or applied problems in the literature--feature in school and undergraduate mathematics reforms aimed at increasing mathematics participation in contexts of inequity and diversity. In this…

  20. Analysis of Mathematics and Sustainability in an Impulsive Eutrophication Controlling System

    Directory of Open Access Journals (Sweden)

    Hengguo Yu

    2013-01-01

    quite accurate to describe the interaction effect of some critical factors (fishermen catch and releasing small fry, etc., which enables a systematic and logical procedure for fitting eutrophication mathematical system to real monitoring data and experiment data. Mathematical theoretical works have been pursuing the investigation of two threshold functions of some critical parameters under the condition of all species persistence, which can in turn provide a theoretical basis for the numerical simulation. Using numerical simulation works, we mainly focus on how to choose the best value of some critical parameters to ensure the sustainability of the eutrophication system so that the eutrophication removal process can be well developed with maximizing economic benefit. These results may be further extended to provide a basis for simulating the algal bloom in the laboratory and understanding the application of some impulsive controlling models about eutrophication removal problems.

  1. Mathematical Analysis of Malfunctions Caused by Seepage Water to the Republic Radioactive Waste Dump in Mochovce

    Directory of Open Access Journals (Sweden)

    Jozef Kuzma

    2007-01-01

    Full Text Available The storage of radioactive waste and the problem of assuring the low and medium radioactive waste is an actual interdisciplinary problem. An important factor influencing on a complex approach to solving these problems is also a creation of suitable technical conditions for its long-term storage. In this article we mathematically analyze an influence of the break covering and its effect on the long-term stability and reliable serviceability of the Republic radioactive waste dump in Mochovce.

  2. The Analysis of Proportional Reasoning Problem in the Indonesian Mathematics Textbook for Junior High School

    OpenAIRE

    Rahmah Johar; Sri Yusniarti; Saminan Saminan

    2017-01-01

    The lack of Indonesian students achievement in the international assessment is due to several factors. Students are not familiar with the problems requiring reasoning, in particular the proportional reasoning. This research aims to identify the distribution and the Level of Cognitive Demands (LCD) of the proportional reasoning problems found in the Year 7 and Year 8 mathematics textbooks based on the 2013 curriculum (revised edition 2014). The data collection was conducted by identifying the ...

  3. Analysis of the e-learning technologies used for teaching mathematics at Tomsk Polytechnic University

    OpenAIRE

    Pakhomova, Elena Grigorievna; Yanushchik, Olga Vladimirovna; Dorofeeva, Maria

    2016-01-01

    This article analyzes the implementation of e-learning technologies in the study of mathematics at Tomsk Polytechnic University. It describes research findings of the suitability of the e-learning technology for first year students of an engineering university. The research involved 248 students and 38 teachers of Tomsk Polytechnic University. The authors surveyed first-year students to check whether they are ready to learn in the electronic environment. In addition, the students and teachers...

  4. Mathematical Chemistry

    OpenAIRE

    Trinajstić, Nenad; Gutman, Ivan

    2002-01-01

    A brief description is given of the historical development of mathematics and chemistry. A path leading to the meeting of these two sciences is described. An attempt is made to define mathematical chemistry, and journals containing the term mathematical chemistry in their titles are noted. In conclusion, the statement is made that although chemistry is an experimental science aimed at preparing new compounds and materials, mathematics is very useful in chemistry, among other things, to produc...

  5. Global gene analysis of oocytes from early stages in human folliculogenesis shows high expression of novel genes in reproduction

    DEFF Research Database (Denmark)

    Markholt, Sara; Grøndahl, M L; Ernst, Erik

    2012-01-01

    The pool of primordial follicles in humans is laid down during embryonic development and follicles can remain dormant for prolonged intervals, often decades, until individual follicles resume growth. The mechanisms that induce growth and maturation of primordial follicles are poorly understood...... but follicles once activated either continue growth or undergo atresia. We have isolated pure populations of oocytes from human primordial, intermediate and primary follicles using laser capture micro-dissection microscopy and evaluated the global gene expression profiles by whole-genome microarray analysis......) and the mitochondrial-encoded ATPase6 (ATP6). Thus, the present study provides not only a technique to capture and perform transcriptome analysis of the sparse material of human oocytes from the earliest follicle stages but further includes a comprehensive basis for our understanding of the regulatory factors...

  6. Gesture analysis of students' majoring mathematics education in micro teaching process

    Science.gov (United States)

    Maldini, Agnesya; Usodo, Budi; Subanti, Sri

    2017-08-01

    In the process of learning, especially math learning, process of interaction between teachers and students is certainly a noteworthy thing. In these interactions appear gestures or other body spontaneously. Gesture is an important source of information, because it supports oral communication and reduce the ambiguity of understanding the concept/meaning of the material and improve posture. This research which is particularly suitable for an exploratory research design to provide an initial illustration of the phenomenon. The goal of the research in this article is to describe the gesture of S1 and S2 students of mathematics education at the micro teaching process. To analyze gesture subjects, researchers used McNeil clarification. The result is two subjects using 238 gesture in the process of micro teaching as a means of conveying ideas and concepts in mathematics learning. During the process of micro teaching, subjects using the four types of gesture that is iconic gestures, deictic gesture, regulator gesturesand adapter gesture as a means to facilitate the delivery of the intent of the material being taught and communication to the listener. Variance gesture that appear on the subject due to the subject using a different gesture patterns to communicate mathematical ideas of their own so that the intensity of gesture that appeared too different.

  7. Comprehensive Analysis of Oculocutaneous Albinism among Non-Hispanic Caucasians Shows that OCA1 Is the Most Prevalent OCA Type

    OpenAIRE

    Hutton, Saunie M.; Spritz, Richard A.

    2008-01-01

    Oculocutaneous albinism (OCA) is a genetically heterogeneous group of disorders characterized by absent or reduced pigmentation of the skin, hair, and eyes. In humans, four genes have been associated with “classical” OCA and another 12 genes with syndromic forms of OCA. To assess the prevalence of different forms of OCA and different gene mutations among non-Hispanic Caucasian patients, we performed DNA sequence analysis of the four genes associated with “classical” OCA (TYR, OCA2, TYRP1, SLC...

  8. Individual patient data meta-analysis shows no association between the SNP rs1800469 in TGFB and late radiotherapy toxicity

    International Nuclear Information System (INIS)

    Barnett, Gillian C.; Elliott, Rebecca M.; Alsner, Jan; Andreassen, Christian N.; Abdelhay, Osama; Burnet, Neil G.; Chang-Claude, Jenny; Coles, Charlotte E.; Gutiérrez-Enríquez, Sara; Fuentes-Raspall, Maria J.; Alonso-Muñoz, Maria C.; Kerns, Sarah; Raabe, Annette; Symonds, R. Paul; Seibold, Petra; Talbot, Chris J.; Wenz, Frederik; Wilkinson, Jennifer; Yarnold, John; Dunning, Alison M.

    2012-01-01

    Background and purpose: Reported associations between risk of radiation-induced normal tissue injury and single nucleotide polymorphisms (SNPs) in TGFB1, encoding the pro-fibrotic cytokine transforming growth factor-beta 1 (TGF-β1), remain controversial. To overcome publication bias, the international Radiogenomics Consortium collected and analysed individual patient level data from both published and unpublished studies. Materials and methods: TGFB1 SNP rs1800469 c.-1347T>C (previously known as C-509T) genotype, treatment-related data, and clinically-assessed fibrosis (measured at least 2 years after therapy) were available in 2782 participants from 11 cohorts. All received adjuvant breast radiotherapy. Associations between late fibrosis or overall toxicity, reported by STAT (Standardised Total Average Toxicity) score, and rs1800469 genotype were assessed. Results: No statistically significant associations between either fibrosis or overall toxicity and rs1800469 genotype were observed with univariate or multivariate regression analysis. The multivariate odds ratio (OR), obtained from meta-analysis, for an increase in late fibrosis grade with each additional rare allele of rs1800469 was 0.98 (95% Confidence Interval (CI) 0.85–1.11). This CI is sufficiently narrow to rule out any clinically relevant effect on toxicity risk in carriers vs. non-carriers with a high probability. Conclusion: This meta-analysis has not confirmed previous reports of association between fibrosis or overall toxicity and rs1800469 genotype in breast cancer patients. It has demonstrated successful collaboration within the Radiogenomics Consortium.

  9. [Benefits of Measures to Promote Development in Language, Mathematics and Singing in Kindergardeners: Analysis of Data Collected at School Entrance Examination in the County of Biberach].

    Science.gov (United States)

    Hart, Ulrike; Wildner, Manfred; Krämer, Daniela; Crispin, Alexander

    2018-02-01

    To evaluate the benefits of implementing measures to promote skills in the areas of language, mathematics and singing in kindergardeners by statistical analysis of data collected during the school entrance examination (ESU) of 4-5-year-old children from the county of Biberach. Study 1 employs multivariate regression analysis to analyse - in chronological order - the ESU data on 4 cohorts (2011-2014; n=7 148) of children of the Biberach county. Study 2 qualitatively compares identical data representative of the entire state of Baden-Württemberg (N=3×80 000) with the Biberach results. Study 3 focuses on the cohort 2014 in Biberach county (n=1 783) and employs logistical regression techniques to correlate curriculum content and child development. There are significant performance improvements in the Biberach population (2011-2014) in the development of language and early mathematics, as well as in visual comprehension and visuomotor skills, but not in the area of gross motor skills. Similar improvements are much more difficult to demonstrate for the entire state of Baden-Württemberg. The detailed analysis of the 2014 Biberach County data reveal that kindergardeners with increased exposure to mathematics will have a decreased risk of failure in early mathematics (OR 0.72) and grammar skills (OR 0.53-0.75). Children with speech impairment or children not fluent in German that had extra language tutorials, typically in small groups and 4 times a week for 30 min, still have a higher risk of failure in all developmental aspects, save gross motor skills (e. g. OR 3.32 in grammar skills, OR 3.08 for hyperactivity). Programs with emphasis on singing have little effect on the above data. The risk of failure in German language is high (OR 2.78) for those of non-German backgrounds, but less in visuomotor skills (OR 0.52) and hyperactivity (OR 0.51). Statistical analyses show positive correlation of curriculum content and early child development for the kindergardens

  10. Mathematics for electronic technology

    CERN Document Server

    Howson, D P

    1975-01-01

    Mathematics for Electronic Technology is a nine-chapter book that begins with the elucidation of the introductory concepts related to use of mathematics in electronic engineering, including differentiation, integration, partial differentiation, infinite series, vectors, vector algebra, and surface, volume and line integrals. Subsequent chapters explore the determinants, differential equations, matrix analysis, complex variable, topography, graph theory, and numerical analysis used in this field. The use of Fourier method for harmonic analysis and the Laplace transform is also described. The ma

  11. A mathematical approach to research problems of science and technology theoretical basis and developments in mathematical modeling

    CERN Document Server

    Ei, Shin-ichiro; Koiso, Miyuki; Ochiai, Hiroyuki; Okada, Kanzo; Saito, Shingo; Shirai, Tomoyuki

    2014-01-01

    This book deals with one of the most novel advances in mathematical modeling for applied scientific technology, including computer graphics, public-key encryption, data visualization, statistical data analysis, symbolic calculation, encryption, error correcting codes, and risk management. It also shows that mathematics can be used to solve problems from nature, e.g., slime mold algorithms. One of the unique features of this book is that it shows readers how to use pure and applied mathematics, especially those mathematical theory/techniques developed in the twentieth century, and developing now, to solve applied problems in several fields of industry. Each chapter includes clues on how to use "mathematics" to solve concrete problems faced in industry as well as practical applications. The target audience is not limited to researchers working in applied mathematics and includes those in engineering, material sciences, economics, and life sciences.

  12. Rainforest Mathematics

    Science.gov (United States)

    Kilpatrick, Jeremy

    2014-01-01

    This paper addresses the contested way that ethnomathematics has sometimes been received by mathematicians and others and what that disagreement might suggest about issues in mathematics education; namely, (a) the relation of ethnomathematics to academic mathematics; (b) recent efforts to reform secondary school mathematics so that it prepares…

  13. Comparative Analysis of Clinical Samples Showing Weak Serum Reaction on AutoVue System Causing ABO Blood Typing Discrepancies.

    Science.gov (United States)

    Jo, Su Yeon; Lee, Ju Mi; Kim, Hye Lim; Sin, Kyeong Hwa; Lee, Hyeon Ji; Chang, Chulhun Ludgerus; Kim, Hyung Hoi

    2017-03-01

    ABO blood typing in pre-transfusion testing is a major component of the high workload in blood banks that therefore requires automation. We often experienced discrepant results from an automated system, especially weak serum reactions. We evaluated the discrepant results by the reference manual method to confirm ABO blood typing. In total, 13,113 blood samples were tested with the AutoVue system; all samples were run in parallel with the reference manual method according to the laboratory protocol. The AutoVue system confirmed ABO blood typing of 12,816 samples (97.7%), and these results were concordant with those of the manual method. The remaining 297 samples (2.3%) showed discrepant results in the AutoVue system and were confirmed by the manual method. The discrepant results involved weak serum reactions (serum reactions, samples from patients who had received stem cell transplants, ABO subgroups, and specific system error messages. Among the 98 samples showing ≤1+ reaction grade in the AutoVue system, 70 samples (71.4%) showed a normal serum reaction (≥2+ reaction grade) with the manual method, and 28 samples (28.6%) showed weak serum reaction in both methods. ABO blood tying of 97.7% samples could be confirmed by the AutoVue system and a small proportion (2.3%) needed to be re-evaluated by the manual method. Samples with a 2+ reaction grade in serum typing do not need to be evaluated manually, while those with ≤1+ reaction grade do.

  14. Secondary Teachers’ Mathematics-related Beliefs and Knowledge about Mathematical Problem-solving

    Science.gov (United States)

    E Siswono, T. Y.; Kohar, A. W.; Hartono, S.

    2017-02-01

    This study investigates secondary teachers’ belief about the three mathematics-related beliefs, i.e. nature of mathematics, teaching mathematics, learning mathematics, and knowledge about mathematical problem solving. Data were gathered through a set of task-based semi-structured interviews of three selected teachers with different philosophical views of teaching mathematics, i.e. instrumental, platonist, and problem solving. Those teachers were selected from an interview using a belief-related task from purposively selected teachers in Surabaya and Sidoarjo. While the interviews about knowledge examine teachers’ problem solving content and pedagogical knowledge, the interviews about beliefs examine their views on several cases extracted from each of such mathematics-related beliefs. Analysis included the categorization and comparison on each of beliefs and knowledge as well as their interaction. Results indicate that all the teachers did not show a high consistency in responding views of their mathematics-related beliefs, while they showed weaknesses primarily on problem solving content knowledge. Findings also point out that teachers’ beliefs have a strong relationship with teachers’ knowledge about problem solving. In particular, the instrumental teacher’s beliefs were consistent with his insufficient knowledge about problem-solving, while both platonist and problem-solving teacher’s beliefs were consistent with their sufficient knowledge of either content or pedagogical problem solving.

  15. Developing Instructional Mathematical Physics Book Based on Inquiry Approach to Improve Students’ Mathematical Problem Solving Ability

    Directory of Open Access Journals (Sweden)

    Syarifah Fadillah

    2017-03-01

    Full Text Available The problem in this research is to know how the process of developing mathematics physics instructional book based on inquiry approach and its supporting documents to improve students' mathematical problem-solving ability. The purpose of this research is to provide mathematical physics instruction based on inquiry approach and its supporting documents (semester learning activity plan, lesson plan and mathematical problem-solving test to improve students' mathematical problem-solving ability. The development of textbook refers to the ADDIE model, including analysis, design, development, implementation, and evaluation. The validation result from the expert team shows that the textbook and its supporting documents are valid. The test results of the mathematical problem-solving skills show that all test questions are valid and reliable. The result of the incorporation of the textbook in teaching and learning process revealed that students' mathematical problem-solving ability using mathematical physics instruction based on inquiry approach book was better than the students who use the regular book.

  16. Perception determinants in learning mathematics

    Science.gov (United States)

    Mokhtar, Siti Fairus; Ali, Noor Rasidah; Rashid, Nurazlina Abdul

    2015-05-01

    This article described a statistical study of students' perception in mathematics. The objective of this study is to identify factors related to perception about learning mathematics among non mathematics' student. This study also determined the relationship between of these factors among non mathematics' student. 43 items questionnaires were distributed to one hundred students in UiTM Kedah who enrolled in the Business Mathematics course. These items were measured by using a semantic scale with the following anchors: 1 = strongly disagree to 7 = strongly agree. A factor analysis of respondents were identified into five factors that influencing the students' perception in mathematics. In my study, factors identified were attitude, interest, role of the teacher, role of peers and usefulness of mathematics that may relate to the perception about learning mathematics among non mathematics' student.

  17. Isolation and expression analysis of EcbZIP17 from different finger millet genotypes shows conserved nature of the gene.

    Science.gov (United States)

    Chopperla, Ramakrishna; Singh, Sonam; Mohanty, Sasmita; Reddy, Nanja; Padaria, Jasdeep C; Solanke, Amolkumar U

    2017-10-01

    Basic leucine zipper (bZIP) transcription factors comprise one of the largest gene families in plants. They play a key role in almost every aspect of plant growth and development and also in biotic and abiotic stress tolerance. In this study, we report isolation and characterization of EcbZIP17 , a group B bZIP transcription factor from a climate smart cereal, finger millet ( Eleusine coracana L.). The genomic sequence of EcbZIP17 is 2662 bp long encompassing two exons and one intron with ORF of 1722 bp and peptide length of 573 aa. This gene is homologous to AtbZIP17 ( Arabidopsis ), ZmbZIP17 (maize) and OsbZIP60 (rice) which play a key role in endoplasmic reticulum (ER) stress pathway. In silico analysis confirmed the presence of basic leucine zipper (bZIP) and transmembrane (TM) domains in the EcbZIP17 protein. Allele mining of this gene in 16 different genotypes by Sanger sequencing revealed no variation in nucleotide sequence, including the 618 bp long intron. Expression analysis of EcbZIP17 under heat stress exhibited similar pattern of expression in all the genotypes across time intervals with highest upregulation after 4 h. The present study established the conserved nature of EcbZIP17 at nucleotide and expression level.

  18. Fundamental remote science research program. Part 2: Status report of the mathematical pattern recognition and image analysis project

    Science.gov (United States)

    Heydorn, R. P.

    1984-01-01

    The Mathematical Pattern Recognition and Image Analysis (MPRIA) Project is concerned with basic research problems related to the study of he Earth from remotely sensed measurements of its surface characteristics. The program goal is to better understand how to analyze the digital image that represents the spatial, spectral, and temporal arrangement of these measurements for purposing of making selected inferences about the Earth. This report summarizes the progress that has been made toward this program goal by each of the principal investigators in the MPRIA Program.

  19. Mathematical model of combined parametrical analysis of indicator process and thermal loading on the Diesel engine piston

    Directory of Open Access Journals (Sweden)

    G. Lebedeva

    2004-06-01

    Full Text Available In the publication the methodical aspects of a mathematical model of the combined parametrical analysis of an indicator process and thermal loading on the diesel engine piston have been considered. A thermodynamic model of a diesel engine cycle is developed. The executed development is intended for use during researches and on the initial stages of design work. Its realization for high revolution diesel engines of perspective type CHN15/15 allowed to choose rational variants for the organization of an indicator process and to prove power ranges of application for not cooled and created cooled oil welded pistons.

  20. Transcriptomic and metabolomic analysis of Yukon Thellungiella plants grown in cabinets and their natural habitat show phenotypic plasticity

    Directory of Open Access Journals (Sweden)

    Guevara David R

    2012-10-01

    Full Text Available Abstract Background Thellungiella salsuginea is an important model plant due to its natural tolerance to abiotic stresses including salt, cold, and water deficits. Microarray and metabolite profiling have shown that Thellungiella undergoes stress-responsive changes in transcript and organic solute abundance when grown under controlled environmental conditions. However, few reports assess the capacity of plants to display stress-responsive traits in natural habitats where concurrent stresses are the norm. Results To determine whether stress-responsive changes observed in cabinet-grown plants are recapitulated in the field, we analyzed leaf transcript and metabolic profiles of Thellungiella growing in its native Yukon habitat during two years of contrasting meteorological conditions. We found 673 genes showing differential expression between field and unstressed, chamber-grown plants. There were comparatively few overlaps between genes expressed under field and cabinet treatment-specific conditions. Only 20 of 99 drought-responsive genes were expressed both in the field during a year of low precipitation and in plants subjected to drought treatments in cabinets. There was also a general pattern of lower abundance among metabolites found in field plants relative to control or stress-treated plants in growth cabinets. Nutrient availability may explain some of the observed differences. For example, proline accumulated to high levels in cold and salt-stressed cabinet-grown plants but proline content was, by comparison, negligible in plants at a saline Yukon field site. We show that proline accumulated in a stress-responsive manner in Thellungiella plants salinized in growth cabinets and in salt-stressed seedlings when nitrogen was provided at 1.0 mM. In seedlings grown on 0.1 mM nitrogen medium, the proline content was low while carbohydrates increased. The relatively higher content of sugar-like compounds in field plants and seedlings on low nitrogen

  1. Transcriptomic and metabolomic analysis of Yukon Thellungiella plants grown in cabinets and their natural habitat show phenotypic plasticity.

    Science.gov (United States)

    Guevara, David R; Champigny, Marc J; Tattersall, Ashley; Dedrick, Jeff; Wong, Chui E; Li, Yong; Labbe, Aurelie; Ping, Chien-Lu; Wang, Yanxiang; Nuin, Paulo; Golding, G Brian; McCarry, Brian E; Summers, Peter S; Moffatt, Barbara A; Weretilnyk, Elizabeth A

    2012-10-01

    Thellungiella salsuginea is an important model plant due to its natural tolerance to abiotic stresses including salt, cold, and water deficits. Microarray and metabolite profiling have shown that Thellungiella undergoes stress-responsive changes in transcript and organic solute abundance when grown under controlled environmental conditions. However, few reports assess the capacity of plants to display stress-responsive traits in natural habitats where concurrent stresses are the norm. To determine whether stress-responsive changes observed in cabinet-grown plants are recapitulated in the field, we analyzed leaf transcript and metabolic profiles of Thellungiella growing in its native Yukon habitat during two years of contrasting meteorological conditions. We found 673 genes showing differential expression between field and unstressed, chamber-grown plants. There were comparatively few overlaps between genes expressed under field and cabinet treatment-specific conditions. Only 20 of 99 drought-responsive genes were expressed both in the field during a year of low precipitation and in plants subjected to drought treatments in cabinets. There was also a general pattern of lower abundance among metabolites found in field plants relative to control or stress-treated plants in growth cabinets. Nutrient availability may explain some of the observed differences. For example, proline accumulated to high levels in cold and salt-stressed cabinet-grown plants but proline content was, by comparison, negligible in plants at a saline Yukon field site. We show that proline accumulated in a stress-responsive manner in Thellungiella plants salinized in growth cabinets and in salt-stressed seedlings when nitrogen was provided at 1.0 mM. In seedlings grown on 0.1 mM nitrogen medium, the proline content was low while carbohydrates increased. The relatively higher content of sugar-like compounds in field plants and seedlings on low nitrogen media suggests that Thellungiella shows

  2. Transcriptomic and metabolomic analysis of Yukon Thellungiella plants grown in cabinets and their natural habitat show phenotypic plasticity

    Science.gov (United States)

    2012-01-01

    Background Thellungiella salsuginea is an important model plant due to its natural tolerance to abiotic stresses including salt, cold, and water deficits. Microarray and metabolite profiling have shown that Thellungiella undergoes stress-responsive changes in transcript and organic solute abundance when grown under controlled environmental conditions. However, few reports assess the capacity of plants to display stress-responsive traits in natural habitats where concurrent stresses are the norm. Results To determine whether stress-responsive changes observed in cabinet-grown plants are recapitulated in the field, we analyzed leaf transcript and metabolic profiles of Thellungiella growing in its native Yukon habitat during two years of contrasting meteorological conditions. We found 673 genes showing differential expression between field and unstressed, chamber-grown plants. There were comparatively few overlaps between genes expressed under field and cabinet treatment-specific conditions. Only 20 of 99 drought-responsive genes were expressed both in the field during a year of low precipitation and in plants subjected to drought treatments in cabinets. There was also a general pattern of lower abundance among metabolites found in field plants relative to control or stress-treated plants in growth cabinets. Nutrient availability may explain some of the observed differences. For example, proline accumulated to high levels in cold and salt-stressed cabinet-grown plants but proline content was, by comparison, negligible in plants at a saline Yukon field site. We show that proline accumulated in a stress-responsive manner in Thellungiella plants salinized in growth cabinets and in salt-stressed seedlings when nitrogen was provided at 1.0 mM. In seedlings grown on 0.1 mM nitrogen medium, the proline content was low while carbohydrates increased. The relatively higher content of sugar-like compounds in field plants and seedlings on low nitrogen media suggests that

  3. Quantitative Analysis of the Contributing Factors Affecting Specialty Care No-Show Rates at Brooke Army Medical Center

    Science.gov (United States)

    2007-03-30

    PHYSICAL THERAPY ,TMC 53 9 14.52% AUDIOLOGY,BAMC 133 22 14.19% OPHTH PEDS,BAMC 28 4 12.50% OCCUPATIONAL THERAPY ,BAMC 135 18 11.76% ALLERGY CLINIC,BAMC...for physical therapy and have a total of 4 appointments set up with that clinic. For this study, only the first referral was counted and not the follow...Nephrology. Some of the other low no-show rate clinics were: Pain Management (1.27%), Endocrinology (1.52%), General Surgery (1.83%), Rheumatology (1.89

  4. Mathematical modelling

    DEFF Research Database (Denmark)

    Blomhøj, Morten

    2004-01-01

    Developing competences for setting up, analysing and criticising mathematical models are normally seen as relevant only from and above upper secondary level. The general belief among teachers is that modelling activities presuppose conceptual understanding of the mathematics involved. Mathematical...... roots for the construction of important mathematical concepts. In addition competences for setting up, analysing and criticising modelling processes and the possible use of models is a formative aim in this own right for mathematics teaching in general education. The paper presents a theoretical...... modelling, however, can be seen as a practice of teaching that place the relation between real life and mathematics into the centre of teaching and learning mathematics, and this is relevant at all levels. Modelling activities may motivate the learning process and help the learner to establish cognitive...

  5. Mathematical Modeling and Pure Mathematics

    Science.gov (United States)

    Usiskin, Zalman

    2015-01-01

    Common situations, like planning air travel, can become grist for mathematical modeling and can promote the mathematical ideas of variables, formulas, algebraic expressions, functions, and statistics. The purpose of this article is to illustrate how the mathematical modeling that is present in everyday situations can be naturally embedded in…

  6. Meta-Analysis of Quantification Methods Shows that Archaea and Bacteria Have Similar Abundances in the Subseafloor

    Science.gov (United States)

    May, Megan K.; Kevorkian, Richard T.; Steen, Andrew D.

    2013-01-01

    There is no universally accepted method to quantify bacteria and archaea in seawater and marine sediments, and different methods have produced conflicting results with the same samples. To identify best practices, we compiled data from 65 studies, plus our own measurements, in which bacteria and archaea were quantified with fluorescent in situ hybridization (FISH), catalyzed reporter deposition FISH (CARD-FISH), polyribonucleotide FISH, or quantitative PCR (qPCR). To estimate efficiency, we defined “yield” to be the sum of bacteria and archaea counted by these techniques divided by the total number of cells. In seawater, the yield was high (median, 71%) and was similar for FISH, CARD-FISH, and polyribonucleotide FISH. In sediments, only measurements by CARD-FISH in which archaeal cells were permeabilized with proteinase K showed high yields (median, 84%). Therefore, the majority of cells in both environments appear to be alive, since they contain intact ribosomes. In sediments, the sum of bacterial and archaeal 16S rRNA gene qPCR counts was not closely related to cell counts, even after accounting for variations in copy numbers per genome. However, qPCR measurements were precise relative to other qPCR measurements made on the same samples. qPCR is therefore a reliable relative quantification method. Inconsistent results for the relative abundance of bacteria versus archaea in deep subsurface sediments were resolved by the removal of CARD-FISH measurements in which lysozyme was used to permeabilize archaeal cells and qPCR measurements which used ARCH516 as an archaeal primer or TaqMan probe. Data from best-practice methods showed that archaea and bacteria decreased as the depth in seawater and marine sediments increased, although archaea decreased more slowly. PMID:24096423

  7. [Geometry, analysis, and computation in mathematics and applied science]. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, D.

    1994-02-01

    The principal investigators` work on a variety of pure and applied problems in Differential Geometry, Calculus of Variations and Mathematical Physics has been done in a computational laboratory and been based on interactive scientific computer graphics and high speed computation created by the principal investigators to study geometric interface problems in the physical sciences. We have developed software to simulate various physical phenomena from constrained plasma flow to the electron microscope imaging of the microstructure of compound materials, techniques for the visualization of geometric structures that has been used to make significant breakthroughs in the global theory of minimal surfaces, and graphics tools to study evolution processes, such as flow by mean curvature, while simultaneously developing the mathematical foundation of the subject. An increasingly important activity of the laboratory is to extend this environment in order to support and enhance scientific collaboration with researchers at other locations. Toward this end, the Center developed the GANGVideo distributed video software system and software methods for running lab-developed programs simultaneously on remote and local machines. Further, the Center operates a broadcast video network, running in parallel with the Center`s data networks, over which researchers can access stored video materials or view ongoing computations. The graphical front-end to GANGVideo can be used to make ``multi-media mail`` from both ``live`` computing sessions and stored materials without video editing. Currently, videotape is used as the delivery medium, but GANGVideo is compatible with future ``all-digital`` distribution systems. Thus as a byproduct of mathematical research, we are developing methods for scientific communication. But, most important, our research focuses on important scientific problems; the parallel development of computational and graphical tools is driven by scientific needs.

  8. Comprehensive analysis of oculocutaneous albinism among non-Hispanic caucasians shows that OCA1 is the most prevalent OCA type.

    Science.gov (United States)

    Hutton, Saunie M; Spritz, Richard A

    2008-10-01

    Oculocutaneous albinism (OCA) is a genetically heterogeneous group of disorders characterized by absent or reduced pigmentation of the skin, hair, and eyes. In humans, four genes have been associated with "classical" OCA and another 12 genes with syndromic forms of OCA. To assess the prevalence of different forms of OCA and different gene mutations among non-Hispanic Caucasian patients, we performed DNA sequence analysis of the four genes associated with "classical" OCA (TYR, OCA2, TYRP1, SLC45A2), the two principal genes associated with syndromic OCA (HPS1, HPS4), and a candidate OCA gene (SILV), in 121 unrelated, unselected non-Hispanic/Latino Caucasian patients carrying the clinical diagnosis of OCA. We identified apparent pathologic TYR gene mutations in 69% of patients, OCA2 mutations in 18%, SLC45A2 mutations in 6%, and no apparent pathological mutations in 7% of patients. We found no mutations of TYRP1, HPS1, HPS4, or SILV in any patients. Although we observed a diversity of mutations for each gene, a relatively small number of different mutant alleles account for a majority of the total. This study demonstrates that, contrary to long-held clinical lore, OCA1, not OCA2, is by far the most frequent cause of OCA among Caucasian patients.

  9. Anatomical Network Analysis Shows Decoupling of Modular Lability and Complexity in the Evolution of the Primate Skull

    Science.gov (United States)

    Esteve-Altava, Borja; Boughner, Julia C.; Diogo, Rui; Villmoare, Brian A.; Rasskin-Gutman, Diego

    2015-01-01

    Modularity and complexity go hand in hand in the evolution of the skull of primates. Because analyses of these two parameters often use different approaches, we do not know yet how modularity evolves within, or as a consequence of, an also-evolving complex organization. Here we use a novel network theory-based approach (Anatomical Network Analysis) to assess how the organization of skull bones constrains the co-evolution of modularity and complexity among primates. We used the pattern of bone contacts modeled as networks to identify connectivity modules and quantify morphological complexity. We analyzed whether modularity and complexity evolved coordinately in the skull of primates. Specifically, we tested Herbert Simon’s general theory of near-decomposability, which states that modularity promotes the evolution of complexity. We found that the skulls of extant primates divide into one conserved cranial module and up to three labile facial modules, whose composition varies among primates. Despite changes in modularity, statistical analyses reject a positive feedback between modularity and complexity. Our results suggest a decoupling of complexity and modularity that translates to varying levels of constraint on the morphological evolvability of the primate skull. This study has methodological and conceptual implications for grasping the constraints that underlie the developmental and functional integration of the skull of humans and other primates. PMID:25992690

  10. Mathematical, numerical and experimental analysis of the swirling flow at a Kaplan runner outlet

    Science.gov (United States)

    Muntean, S.; Ciocan, T.; Susan-Resiga, R. F.; Cervantes, M.; Nilsson, H.

    2012-11-01

    The paper presents a novel mathematical model for a-priori computation of the swirling flow at Kaplan runners outlet. The model is an extension of the initial version developed by Susan-Resiga et al [1], to include the contributions of non-negligible radial velocity and of the variable rothalpy. Simple analytical expressions are derived for these additional data from three-dimensional numerical simulations of the Kaplan turbine. The final results, i.e. velocity components profiles, are validated against experimental data at two operating points, with the same Kaplan runner blades opening, but variable discharge.

  11. Mathematical, numerical and experimental analysis of the swirling flow at a Kaplan runner outlet

    International Nuclear Information System (INIS)

    Muntean, S; Ciocan, T; Susan-Resiga, R F; Cervantes, M; Nilsson, H

    2012-01-01

    The paper presents a novel mathematical model for a-priori computation of the swirling flow at Kaplan runners outlet. The model is an extension of the initial version developed by Susan-Resiga et al [1], to include the contributions of non-negligible radial velocity and of the variable rothalpy. Simple analytical expressions are derived for these additional data from three-dimensional numerical simulations of the Kaplan turbine. The final results, i.e. velocity components profiles, are validated against experimental data at two operating points, with the same Kaplan runner blades opening, but variable discharge.

  12. Mathematics in everyday life

    CERN Document Server

    Haigh, John

    2016-01-01

    How does mathematics impact everyday events? The purpose of this book is to show a range of examples where mathematics can be seen at work in everyday life. From money (APR, mortgage repayments, personal finance), simple first and second order ODEs, sport and games (tennis, rugby, athletics, darts, tournament design, soccer, snooker), business (stock control, linear programming, check digits, promotion policies, investment), the social sciences (voting methods, Simpson’s Paradox, drug testing, measurements of inequality) to TV game shows and even gambling (lotteries, roulette, poker, horse racing), the mathematics behind commonplace events is explored. Fully worked examples illustrate the ideas discussed and each chapter ends with a collection of exercises. Everyday Mathematics supports other first year modules by giving students extra practice in working with calculus, linear algebra, geometry, trigonometry and probability. Secondary/high school level mathematics is all that is required for students to und...

  13. INTERSUBJECT CONNECTIONS OF COURSE OF MATHEMATICAL LOGIC AND OTHER MATHEMATICAL COURSES AT PREPARATION OF FUTURE TEACHER OF MATHEMATICS

    Directory of Open Access Journals (Sweden)

    Yu.I. Sinko

    2012-03-01

    Full Text Available In this article the interconnections of course of mathematical logic with other mathematical courses – geometry, algebra and theory of numbers, mathematical analysis, and also with the courses of mathematics teaching methodology, history of mathematics in the system of preparation of teachers of mathematics in pedagogical Institute of higher education are analyzed. The presence of connections between the elements of the system and their quality is the important description of the pedagogical system.

  14. Thermodynamic modeling of transcription: sensitivity analysis differentiates biological mechanism from mathematical model-induced effects.

    Science.gov (United States)

    Dresch, Jacqueline M; Liu, Xiaozhou; Arnosti, David N; Ay, Ahmet

    2010-10-24

    Quantitative models of gene expression generate parameter values that can shed light on biological features such as transcription factor activity, cooperativity, and local effects of repressors. An important element in such investigations is sensitivity analysis, which determines how strongly a model's output reacts to variations in parameter values. Parameters of low sensitivity may not be accurately estimated, leading to unwarranted conclusions. Low sensitivity may reflect the nature of the biological data, or it may be a result of the model structure. Here, we focus on the analysis of thermodynamic models, which have been used extensively to analyze gene transcription. Extracted parameter values have been interpreted biologically, but until now little attention has been given to parameter sensitivity in this context. We apply local and global sensitivity analyses to two recent transcriptional models to determine the sensitivity of individual parameters. We show that in one case, values for repressor efficiencies are very sensitive, while values for protein cooperativities are not, and provide insights on why these differential sensitivities stem from both biological effects and the structure of the applied models. In a second case, we demonstrate that parameters that were thought to prove the system's dependence on activator-activator cooperativity are relatively insensitive. We show that there are numerous parameter sets that do not satisfy the relationships proferred as the optimal solutions, indicating that structural differences between the two types of transcriptional enhancers analyzed may not be as simple as altered activator cooperativity. Our results emphasize the need for sensitivity analysis to examine model construction and forms of biological data used for modeling transcriptional processes, in order to determine the significance of estimated parameter values for thermodynamic models. Knowledge of parameter sensitivities can provide the necessary

  15. Mathematical Thinking and Creativity through Mathematical Problem Posing and Solving

    Directory of Open Access Journals (Sweden)

    María F. Ayllón

    2016-04-01

    Full Text Available This work shows the relationship between the development of mathematical thinking and creativity with mathematical problem posing and solving. Creativity and mathematics are disciplines that do not usually appear together. Both concepts constitute complex processes sharing elements, such as fluency (number of ideas, flexibility (range of ideas, novelty (unique idea and elaboration (idea development. These factors contribute, among others, to the fact that schoolchildren are competent in mathematics. The problem solving and posing are a very powerful evaluation tool that shows the mathematical reasoning and creative level of a person. Creativity is part of the mathematics education and is a necessary ingredient to perform mathematical assignments. This contribution presents some important research works about problem posing and solving related to the development of mathematical knowledge and creativity. To that end, it is based on various beliefs reflected in the literature with respect to notions of creativity, problem solving and posing.

  16. Morphometric analysis of molars in a Middle Pleistocene population shows a mosaic of 'modern' and Neanderthal features.

    Science.gov (United States)

    Martinón-Torres, María; Spěváčková, Petra; Gracia-Téllez, Ana; Martínez, Ignacio; Bruner, Emiliano; Arsuaga, Juan Luis; Bermúdez de Castro, José María

    2013-10-01

    Previous studies of upper first molar (M1) crown shape have shown significant differences between Homo sapiens and Homo neanderthalensis that were already present in the European Middle Pleistocene populations, including the large dental sample from Atapuerca-Sima de los Huesos (SH). Analysis of other M1 features such as the total crown base area, cusp proportions, cusp angles and occlusal polygon have confirmed the differences between both lineages, becoming a useful tool for the taxonomic assignment of isolated teeth from Late Pleistocene sites. However, until now the pattern of expression of these variables has not been known for the SH sample. This fossil sample, the largest collection from the European Middle Pleistocene, is generally interpreted as being from the direct ancestors of Neanderthals, and thus is a reference sample for assessing the origin of the Neanderthal morphologies. Surprisingly, our study reveals that SH M(1) s present a unique mosaic of H. neanderthalensis and H. sapiens features. Regarding the cusp angles and the relative occlusal polygon area, SH matches the H. neanderthalensis pattern. However, regarding the total crown base area and relative cusps size, SH M(1) s are similar to H. sapiens, with a small crown area, a strong hypocone reduction and a protocone enlargement, although the protocone expansion in SH is significantly larger than in any other group studied. The SH dental sample calls into question the uniqueness of some so-called modern traits. Our study also sounds a note of caution on the use of M(1) occlusal morphology for the alpha taxonomy of isolated M(1) s. © 2013 Anatomical Society.

  17. Morphometric analysis of molars in a Middle Pleistocene population shows a mosaic of ‘modern’ and Neanderthal features

    Science.gov (United States)

    Martinón-Torres, María; Spěváčková, Petra; Gracia-Téllez, Ana; Martínez, Ignacio; Bruner, Emiliano; Arsuaga, Juan Luis; Bermúdez de Castro, José María

    2013-01-01

    Previous studies of upper first molar (M1) crown shape have shown significant differences between Homo sapiens and Homo neanderthalensis that were already present in the European Middle Pleistocene populations, including the large dental sample from Atapuerca-Sima de los Huesos (SH). Analysis of other M1 features such as the total crown base area, cusp proportions, cusp angles and occlusal polygon have confirmed the differences between both lineages, becoming a useful tool for the taxonomic assignment of isolated teeth from Late Pleistocene sites. However, until now the pattern of expression of these variables has not been known for the SH sample. This fossil sample, the largest collection from the European Middle Pleistocene, is generally interpreted as being from the direct ancestors of Neanderthals, and thus is a reference sample for assessing the origin of the Neanderthal morphologies. Surprisingly, our study reveals that SH M1s present a unique mosaic of H. neanderthalensis and H. sapiens features. Regarding the cusp angles and the relative occlusal polygon area, SH matches the H. neanderthalensis pattern. However, regarding the total crown base area and relative cusps size, SH M1s are similar to H. sapiens, with a small crown area, a strong hypocone reduction and a protocone enlargement, although the protocone expansion in SH is significantly larger than in any other group studied. The SH dental sample calls into question the uniqueness of some so-called modern traits. Our study also sounds a note of caution on the use of M1 occlusal morphology for the alpha taxonomy of isolated M1s. PMID:23914934

  18. Meta-analysis shows similar re-bleeding rates among Western and Eastern populations after index video capsule endoscopy.

    Science.gov (United States)

    Tziatzios, Georgios; Gkolfakis, Paraskevas; Hassan, Cesare; Toth, Ervin; Zullo, Angelo; Koulaouzidis, Anastasios; Dimitriadis, George D; Triantafyllou, Konstantinos

    2018-03-01

    Video capsule endoscopy (VCE) is the first-line diagnostic procedure for investigating obscure gastrointestinal bleeding (OGIB). Different re-bleeding rates following index VCE have been reported among Western and Eastern studies. We conducted a comprehensive literature search to identify studies examining re-bleeding rates after VCE for OGIB. Meta-analysis assessed the pooled proportion of re-bleeding events after VCE for OGIB according to study's origin (Western vs. Eastern) and according to the length of follow-up (≥24 months vs. Western and 16 Eastern) studies with 5796 patients. Significant heterogeneity was detected among meta-analyzed studies. Overall, the pooled re-bleeding rate was similar between Western (29%; 95% CI: 23-34) and Eastern (21%; 95% CI: 15-27) populations, irrespective of the length of follow-up. The odds of re-bleeding was significantly higher after positive as compared to negative index VCE in Eastern studies (OR: 1.77; 95% CI: 1.07-2.94). Application of specific treatment after positive index VCE was associated with lower re-bleeding odds in both Western (OR: 0.37; 95% CI: 0.16-0.87) and Eastern (OR: 0.39; 95% CI: 0.21-0.72) populations. Patients undergoing VCE for OGIB have similar re-bleeding rates in the East and the West, regardless of the length of follow-up. However, increased re-bleeding odds after positive index VCE is observed in Eastern studies. Copyright © 2018 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  19. X-ray survival characteristics and genetic analysis for nine saccharomyces deletion mutants that show altered radiation sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Game, John C.; Williamson, Marsha S.; Baccari, Clelia

    2004-01-07

    The availability of a genome-wide set of Saccharomyces deletion mutants provides a chance to identify all the yeast genes involved in DNA repair. Using X-rays, we are screening these mutants to identify additional genes that show increased sensitivity to the lethal effects of ionizing radiation. For each mutant identified as sensitive, we are confirming that the sensitivity phenotype co-segregates with the deletion allele and are obtaining multipoint survival-versus-dose assays in at least two haploid and one homozygous diploid strains. We present data for deletion mutants involving the genes DOT1, MDM20, NAT3, SPT7, SPT20, GCN5, HFI1, DCC1 and VID21/EAF1, and discuss their potential roles in repair. Eight of these genes have a clear radiation-sensitive phenotype when deleted, but the ninth, GCN5, has at most a borderline phenotype. None of the deletions confer substantial sensitivity to ultra-violet radiation, although one or two may confer marginal sensitivity. The DOT1 gene is of interest because its only known function is to methylate one lysine residue in the core of the histone H3 protein. We find that histone H3 mutants (supplied by K. Struhl) in which this residue is replaced by other amino-acids are also X-ray sensitive, seeming to confirm that methylation of the lysine-79 residue is required for effective repair of radiation damage.

  20. Comprehensive behavioral analysis of Ox1r-/- mice showed implication of orexin receptor-1 in mood, anxiety and social behavior

    Directory of Open Access Journals (Sweden)

    Md Golam Abbas

    2015-12-01

    Full Text Available Neuropeptides orexin A and orexin B, which are exclusively produced by neurons in the lateral hypothalamic area, play an important role in the regulation of a wide range of behaviors and homeostatic processes, including regulation of sleep/wakefulness states and energy homeostasis. The orexin system has close anatomical and functional relationships with systems that regulate the autonomic nervous system, emotion, mood, the reward system and sleep/wakefulness states. Recent pharmacological studies using selective antagonists have suggested that orexin receptor-1 (OX1R is involved in physiological processes that regulate emotion, the reward system and autonomic nervous system. Here, we examined Ox1r-/- mice with a comprehensive behavioral test battery to screen additional OX1R functions. Ox1r-/- mice showed increased anxiety-like behavior, altered depression-like behavior, slightly decreased spontaneous locomotor activity, reduced social interaction, increased startle response and decreased prepulse inhibition. These results suggest that OX1R plays roles in social behaviour and sensory motor gating in addition to roles in mood and anxiety.

  1. An actuarial analysis shows that offering lung cancer screening as an insurance benefit would save lives at relatively low cost.

    Science.gov (United States)

    Pyenson, Bruce S; Sander, Marcia S; Jiang, Yiding; Kahn, Howard; Mulshine, James L

    2012-04-01

    Lung cancer screening is not established as a public health practice, yet the results of a recent large randomized controlled trial showed that screening with low-dose spiral computed tomography reduces lung cancer mortality. Using actuarial models, this study estimated the costs and benefits of annual lung cancer screening offered as a commercial insurance benefit in the high-risk US population ages 50-64. Assuming current commercial reimbursement rates for treatment, we found that screening would cost about $1 per insured member per month in 2012 dollars. The cost per life-year saved would be below $19,000, an amount that compares favorably with screening for cervical, breast, and colorectal cancers. Our results suggest that commercial insurers should consider lung cancer screening of high-risk individuals to be high-value coverage and provide it as a benefit to people who are at least fifty years old and have a smoking history of thirty pack-years or more. We also believe that payers and patients should demand screening from high-quality, low-cost providers, thus helping set an example of efficient system innovation.

  2. Transcriptome analysis shows activation of the arginine deiminase pathway in Lactococcus lactis as a response to ethanol stress.

    Science.gov (United States)

    Díez, Lorena; Solopova, Ana; Fernández-Pérez, Rocío; González, Miriam; Tenorio, Carmen; Kuipers, Oscar P; Ruiz-Larrea, Fernanda

    2017-09-18

    This paper describes the molecular response of Lactococcus lactis NZ9700 to ethanol. This strain is a well-known nisin producer and a lactic acid bacteria (LAB) model strain. Global transcriptome profiling using DNA microarrays demonstrated a bacterial adaptive response to the presence of 2% ethanol in the culture broth and differential expression of 67 genes. The highest up-regulation was detected for those genes involved in arginine degradation through the arginine deiminase (ADI) pathway (20-40 fold up-regulation). The metabolic responses to ethanol of wild type L. lactis strains were studied and compared to those of regulator-deletion mutants MG∆argR and MG∆ahrC. The results showed that in the presence of 2% ethanol those strains with an active ADI pathway reached higher growth rates when arginine was available in the culture broth than in absence of arginine. In a chemically defined medium strains with an active ADI pathway consumed arginine and produced ornithine in the presence of 2% ethanol, hence corroborating that arginine catabolism is involved in the bacterial response to ethanol. This is the first study of the L. lactis response to ethanol stress to demonstrate the relevance of arginine catabolism for bacterial adaptation and survival in an ethanol containing medium. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Refresher Course in Mathematics

    Indian Academy of Sciences (India)

    at Department of Mathematics, Berhampur University, Berhampur 760007, Orissa ... Applications are invited. from University/College teachers and Researchers interested in ... Pre-requisites: A basic knowledge of analysis, topology, differential ...

  4. Mathematical Thinking and Creativity through Mathematical Problem Posing and Solving

    Science.gov (United States)

    Ayllón, María F.; Gómez, Isabel A.; Ballesta-Claver, Julio

    2016-01-01

    This work shows the relationship between the development of mathematical thinking and creativity with mathematical problem posing and solving. Creativity and mathematics are disciplines that do not usually appear together. Both concepts constitute complex processes sharing elements, such as fluency (number of ideas), flexibility (range of ideas),…

  5. Contemporary mathematical physics

    CERN Document Server

    Dobrushin, R L; Shubin, M A; Vershik, Anatoly M

    1996-01-01

    This first of a two-volume collection is a celebration of the scientific heritage of F. A. Berezin (1931-1980). Before his untimely death, Berezin had an important influence on physics and mathematics, discovering new ideas in mathematical physics, representation theory, analysis, geometry, and other areas of mathematics. His crowning achievements were the introduction of a new notion of deformation quantization, and Grassmannian analysis ("supermathematics"). Collected here are papers by his many of his colleagues and others who worked in related areas, representing a wide spectrum of topics

  6. When to Renew Software Licences at HPC Centres? A Mathematical Analysis

    International Nuclear Information System (INIS)

    Baolai, Ge; MacIsaac, Allan B

    2010-01-01

    In this paper we study a common problem faced by many high performance computing (HPC) centres: When and how to renew commercial software licences. Software vendors often sell perpetual licences along with forward update and support contracts at an additional, annual cost. Every year or so, software support personnel and the budget units of HPC centres are required to make the decision of whether or not to renew such support, and usually such decisions are made intuitively. The total cost for a continuing support contract can, however, be costly. One might therefore want a rational answer to the question of whether the option for a renewal should be exercised and when. In an attempt to study this problem within a market framework, we present the mathematical problem derived for the day to day operation of a hypothetical HPC centre that charges for the use of software packages. In the mathematical model, we assume that the uncertainty comes from the demand, number of users using the packages, as well as the price. Further we assume the availability of up to date software versions may also affect the demand. We develop a renewal strategy that aims to maximize the expected profit from the use the software under consideration. The derived problem involves a decision tree, which constitutes a numerical procedure that can be processed in parallel.

  7. When to Renew Software Licences at HPC Centres? A Mathematical Analysis

    Science.gov (United States)

    Baolai, Ge; MacIsaac, Allan B.

    2010-11-01

    In this paper we study a common problem faced by many high performance computing (HPC) centres: When and how to renew commercial software licences. Software vendors often sell perpetual licences along with forward update and support contracts at an additional, annual cost. Every year or so, software support personnel and the budget units of HPC centres are required to make the decision of whether or not to renew such support, and usually such decisions are made intuitively. The total cost for a continuing support contract can, however, be costly. One might therefore want a rational answer to the question of whether the option for a renewal should be exercised and when. In an attempt to study this problem within a market framework, we present the mathematical problem derived for the day to day operation of a hypothetical HPC centre that charges for the use of software packages. In the mathematical model, we assume that the uncertainty comes from the demand, number of users using the packages, as well as the price. Further we assume the availability of up to date software versions may also affect the demand. We develop a renewal strategy that aims to maximize the expected profit from the use the software under consideration. The derived problem involves a decision tree, which constitutes a numerical procedure that can be processed in parallel.

  8. A mathematical analysis of adaptations to the metabolic fate of fructose in essential fructosuria subjects.

    Science.gov (United States)

    Allen, R J; Musante, Cynthia J

    2018-04-17

    Fructose is a major component of Western diets and is implicated in the pathogenesis of obesity and type 2 diabetes. In response to an oral challenge, the majority of fructose is cleared during "first-pass" liver metabolism, primarily via phosphorylation by ketohexokinase (KHK). A rare benign genetic deficiency in KHK, called essential fructosuria (EF), leads to altered fructose metabolism. The only reported symptom of EF is the appearance of fructose in the urine following either oral or intravenous fructose administration. Here we develop and use a mathematical model to investigate the adaptations to altered fructose metabolism in people with EF. Firstly, the model is calibrated to fit available data in normal healthy subjects. Then, to mathematically represent EF subjects we systematically implement metabolic adaptations such that model simulations match available data for this phenotype. We hypothesize that these modifications represent the major metabolic adaptations present in these subjects. This modeling approach suggests that several other aspects of fructose metabolism, beyond hepatic KHK deficiency, are altered and contribute to the etiology of this benign condition. Specifically, we predict that fructose absorption into the portal vein is altered, peripheral metabolism is slowed, renal re-absorption of fructose is mostly ablated and that alternate pathways for hepatic metabolism of fructose are up-regulated. Moreover, these findings have implications for drug discovery and development, suggesting that the therapeutic targeting of fructose metabolism could lead to unexpected metabolic adaptations, potentially due to a physiological response to high fructose conditions.

  9. An integrated study of spatial multicriteria analysis and mathematical modelling for managed aquifer recharge site suitability mapping and site ranking at Northern Gaza coastal aquifer.

    Science.gov (United States)

    Rahman, Mohammad Azizur; Rusteberg, Bernd; Uddin, Mohammad Salah; Lutz, Annegret; Saada, Muath Abu; Sauter, Martin

    2013-07-30

    This paper describes an integrated approach of site suitability mapping and ranking of the most suitable sites, for the implementation of Managed Aquifer Recharge (MAR) projects, using spatial multicriteria decision analysis (SMCDA) techniques and mathematical modelling. The SMCDA procedure contains constraint mapping, site suitability analysis with criteria standardization and weighting, criteria overlay by analytical hierarchy process (AHP) combined with weighted linear combination (WLC) and ordered weighted averaging (OWA), and sensitivity analysis. The hydrogeological impacts of the selected most suitable sites were quantified by using groundwater flow and transport modelling techniques. Finally, ranking of the selected sites was done with the WLC method. The integrated approach is demonstrated by a case study in the coastal aquifer of North Gaza. Constraint mapping shows that 50% of the total study area is suitable for MAR implementation. About 25% of the total area is "very good" and 25% percent is "good" for MAR, according to the site suitability analysis. Six locations were selected and ranked against six representative decision criteria. Long term (year 2003 to year 2040) groundwater flow and transport simulations were performed to quantify the selected criteria under MAR project operation conditions at the selected sites. Finally, the suitability mapping and hydrogeological investigation recommends that the location of the existing infiltration ponds, constructed near the planned North Gaza Wastewater Treatment Plant (NGWWTP) is most suitable for MAR project implementation. This paper concludes that mathematical modelling should be combined with the SMCDA technique in order to select the best location for MAR project implementation. Besides MAR project implementation, the generalised approach can be applicable for any other water resources development project that deals with site selection and implementation. Copyright © 2013 Elsevier Ltd. All rights

  10. Carl Stumpf's philosophy of mathematics

    NARCIS (Netherlands)

    Ierna, Carlo

    2015-01-01

    Like most of Franz Brentano's students, Carl Stumpf showed an interest in the philosophy of mathematics. In particular, Stumpf wrote his habilitation thesis On the Foundations of Mathematics, used mathematical examples in central parts of his lectures, and later returned to the topic in the

  11. An analysis of mathematical connection ability based on student learning style on visualization auditory kinesthetic (VAK) learning model with self-assessment

    Science.gov (United States)

    Apipah, S.; Kartono; Isnarto

    2018-03-01

    This research aims to analyze the quality of VAK learning with self-assessment toward the ability of mathematical connection performed by students and to analyze students’ mathematical connection ability based on learning styles in VAK learning model with self-assessment. This research applies mixed method type with concurrent embedded design. The subject of this research consists of VIII grade students from State Junior High School 9 Semarang who apply visual learning style, auditory learning style, and kinesthetic learning style. The data of learning style is collected by using questionnaires, the data of mathematical connection ability is collected by performing tests, and the data of self-assessment is collected by using assessment sheets. The quality of learning is qualitatively valued from planning stage, realization stage, and valuation stage. The result of mathematical connection ability test is analyzed quantitatively by mean test, conducting completeness test, mean differentiation test, and mean proportional differentiation test. The result of the research shows that VAK learning model results in well-qualified learning regarded from qualitative and quantitative sides. Students with visual learning style perform the highest mathematical connection ability, students with kinesthetic learning style perform average mathematical connection ability, and students with auditory learning style perform the lowest mathematical connection ability.

  12. Mathematics in narratives of Geodetic expeditions.

    Science.gov (United States)

    Terrall, Mary

    2006-12-01

    In eighteenth-century France, geodesy (the measure of the earth's shape) became an arena where mathematics and narrative intersected productively. Mathematics played a crucial role not only in the measurements and analysis necessary to geodesy but also in the narrative accounts that presented the results of elaborate and expensive expeditions to the reading public. When they returned to France to write these accounts after their travels, mathematician-observers developed a variety of ways to display numbers and mathematical arguments and techniques. The numbers, equations, and diagrams they produced could not be separated from the story of their acquisition. Reading these accounts for the interplay of these two aspects--the mathematical and the narrative--shows how travelers articulated the intellectual and physical difficulties of their work to enhance the value of their results for specialist and lay readers alike.

  13. Mathematical Modeling and Analysis Methodology for Opportunistic Routing in Wireless Multihop Networks

    Directory of Open Access Journals (Sweden)

    Wang Dongyang

    2015-01-01

    Full Text Available Modeling the forwarding feature and analyzing the performance theoretically for opportunistic routing in wireless multihop network are of great challenge. To address this issue, a generalized geometric distribution (GGD is firstly proposed. Based on the GGD, the forwarding probability between any two forwarding candidates could be calculated and it can be proved that the successful delivery rate after several transmissions of forwarding candidates is irrelevant to the priority rule. Then, a discrete-time queuing model is proposed to analyze mean end-to-end delay (MED of a regular opportunistic routing with the knowledge of the forwarding probability. By deriving the steady-state joint generating function of the queue length distribution, MED for directly connected networks and some special cases of nondirectly connected networks could be ultimately determined. Besides, an approximation approach is proposed to assess MED for the general cases in the nondirectly connected networks. By comparing with a large number of simulation results, the rationality of the analysis is validated. Both the analysis and simulation results show that MED varies with the number of forwarding candidates, especially when it comes to connected networks; MED increases more rapidly than that in nondirectly connected networks with the increase of the number of forwarding candidates.

  14. Dynamic analysis of the PEC fast reactor vessel: on-site tests and mathematical models

    International Nuclear Information System (INIS)

    Zola, Maurizio; Martelli, Alessandro; Maresca, Giuseppe; Masoni, Paolo; Scandola, Giani; Descleves, Pierre

    1988-01-01

    This paper presents the main features and results of the on-site dynamic tests and the related numerical analysis carried out for the PEC reactor vessel. The purpose is to provide an example of on-site testing of large components, stressing the problems encountered during the experiments, as well as in the processing phase of the test results and for the comparisons between calculations and measurements. Tests, performed by ISMES on behalf of ENEA, allowed the dynamic response of the empty vessel to be measured, thus providing data for the verification of the numerical models of the vessel supporting structure adopted in the PEC reactor-block seismic analysis. An axisymmetric model of the vessel, implemented in the vessel, implemented in the NOVAK code, had been developed in the framework of the detailed numerical studies performed by NOVATOME (again on behalf of ENEA), to check the beam schematization with fluid added mass model adopted by ANSALDO in SAP-IV and ANSYS for the reactor-block design calculations. Furthermore, a numerical model, describing vessel supporting structure in detail, was also developed by ANSALDO and implemented in the SAP-IV code. The test conditions were analysed by use of these and the design models. Comparisons between calculations and measurements showed particularly good agreement with regard to first natural frequency of the vessel and rocking stiffness of the vessel supporting structure, i.e. those parameters on which vessel seismic amplification mainly depends: this demonstrated the adequacy of the design analysis to correctly calculate the seismic motion at the PEC core diagrid. (author)

  15. When Do Girls Prefer Football to Fashion? An Analysis of Female Underachievement in Relation to "Realistic" Mathematics Context.

    Science.gov (United States)

    Boaler, Jo

    1994-01-01

    Reports on a study of the move away from abstract calculations toward "mathematics in context" among 50 British female secondary school students. Discusses implications of findings in relation to reported female underachievement and disinterest in school mathematics. (CFR)

  16. Application of Adjusted Canonical Correlation Analysis (ACCA) to study the association between mathematics in Level 1 and Level 2 and performance of engineering disciplines in Level 2

    Science.gov (United States)

    Peiris, T. S. G.; Nanayakkara, K. A. D. S. A.

    2017-09-01

    Mathematics plays a key role in engineering sciences as it assists to develop the intellectual maturity and analytical thinking of engineering students and exploring the student academic performance has received great attention recently. The lack of control over covariates motivates the need for their adjustment when measuring the degree of association between two sets of variables in Canonical Correlation Analysis (CCA). Thus to examine the individual effects of mathematics in Level 1 and Level 2 on engineering performance in Level 2, two adjusted analyses in CCA: Part CCA and Partial CCA were applied for the raw marks of engineering undergraduates for three different disciplines, at the Faculty of Engineering, University of Moratuwa, Sri Lanka. The joint influence of mathematics in Level 1 and Level 2 is significant on engineering performance in Level 2 irrespective of the engineering disciplines. The individual effect of mathematics in Level 2 is significantly higher compared to the individual effect of mathematics in Level 1 on engineering performance in Level 2. Furthermore, the individual effect of mathematics in Level 1 can be negligible. But, there would be a notable indirect effect of mathematics in Level 1 on engineering performance in Level 2. It can be concluded that the joint effect of mathematics in both Level 1 and Level 2 is immensely beneficial to improve the overall academic performance at the end of Level 2 of the engineering students. Furthermore, it was found that the impact mathematics varies among engineering disciplines. As partial CCA and partial CCA are not widely explored in applied work, it is recommended to use these techniques for various applications.

  17. Defining the Relationship of Student Achievement Between STEM Subjects Through Canonical Correlation Analysis of 2011 Trends in International Mathematics and Science Study (TIMSS) Data

    Science.gov (United States)

    O'Neal, Melissa Jean

    Canonical correlation analysis was used to analyze data from Trends in International Mathematics and Science Study (TIMSS) 2011 achievement databases encompassing information from fourth/eighth grades. Student achievement in life science/biology was correlated with achievement in mathematics and other sciences across three analytical areas: mathematics and science student performance, achievement in cognitive domains, and achievement in content domains. Strong correlations between student achievement in life science/biology with achievement in mathematics and overall science occurred for both high- and low-performing education systems. Hence, partial emphases on the inter-subject connections did not always lead to a better student learning outcome in STEM education. In addition, student achievement in life science/biology was positively correlated with achievement in mathematics and science cognitive domains; these patterns held true for correlations of life science/biology with mathematics as well as other sciences. The importance of linking student learning experiences between and within STEM domains to support high performance on TIMSS assessments was indicated by correlations of moderate strength (57 TIMSS assessments was indicated by correlations of moderate strength (57 mathematics, and other sciences. At the eighth grade level, students who built increasing levels of cognitive complexity upon firm foundations were prepared for successful learning throughout their educational careers. The results from this investigation promote a holistic design of school learning opportunities to improve student achievement in life science/biology and other science, technology, engineering, and mathematics (STEM) subjects at the elementary and middle school levels. While the curriculum can vary from combined STEM subjects to separated mathematics or science courses, both professional learning communities (PLC) for teachers and problem-based learning (PBL) for learners can be

  18. Mathematical modeling and fuzzy availability analysis for serial processes in the crystallization system of a sugar plant

    Science.gov (United States)

    Aggarwal, Anil Kr.; Kumar, Sanjeev; Singh, Vikram

    2017-03-01

    The binary states, i.e., success or failed state assumptions used in conventional reliability are inappropriate for reliability analysis of complex industrial systems due to lack of sufficient probabilistic information. For large complex systems, the uncertainty of each individual parameter enhances the uncertainty of the system reliability. In this paper, the concept of fuzzy reliability has been used for reliability analysis of the system, and the effect of coverage factor, failure and repair rates of subsystems on fuzzy availability for fault-tolerant crystallization system of sugar plant is analyzed. Mathematical modeling of the system is carried out using the mnemonic rule to derive Chapman-Kolmogorov differential equations. These governing differential equations are solved with Runge-Kutta fourth-order method.

  19. Time-lapse analysis and mathematical characterization elucidate novel mechanisms underlying muscle morphogenesis.

    Directory of Open Access Journals (Sweden)

    Chelsi J Snow

    2008-10-01

    Full Text Available Skeletal muscle morphogenesis transforms short muscle precursor cells into long, multinucleate myotubes that anchor to tendons via the myotendinous junction (MTJ. In vertebrates, a great deal is known about muscle specification as well as how somitic cells, as a cohort, generate the early myotome. However, the cellular mechanisms that generate long muscle fibers from short cells and the molecular factors that limit elongation are unknown. We show that zebrafish fast muscle fiber morphogenesis consists of three discrete phases: short precursor cells, intercalation/elongation, and boundary capture/myotube formation. In the first phase, cells exhibit randomly directed protrusive activity. The second phase, intercalation/elongation, proceeds via a two-step process: protrusion extension and filling. This repetition of protrusion extension and filling continues until both the anterior and posterior ends of the muscle fiber reach the MTJ. Finally, both ends of the muscle fiber anchor to the MTJ (boundary capture and undergo further morphogenetic changes as they adopt the stereotypical, cylindrical shape of myotubes. We find that the basement membrane protein laminin is required for efficient elongation, proper fiber orientation, and boundary capture. These early muscle defects in the absence of either lamininbeta1 or laminingamma1 contrast with later dystrophic phenotypes in lamininalpha2 mutant embryos, indicating discrete roles for different laminin chains during early muscle development. Surprisingly, genetic mosaic analysis suggests that boundary capture is a cell-autonomous phenomenon. Taken together, our results define three phases of muscle fiber morphogenesis and show that the critical second phase of elongation proceeds by a repetitive process of protrusion extension and protrusion filling. Furthermore, we show that laminin is a novel and critical molecular cue mediating fiber orientation and limiting muscle cell length.

  20. DYNAMIC MATHEMATICS SOFTWARE: A QUANTITATIVE ANALYSIS IN THE CONTEXT OF THE PREPARATION OF MATH TEACHER

    Directory of Open Access Journals (Sweden)

    Olena V. Semenikhina

    2015-09-01

    Full Text Available The results of the pedagogical experiment to clarify the number of dynamic mathematics software, which modern math teacher should know, are described.Quantitative results of the questionnaire survey of math teachers concerning the use of DMS in the learning process are given. Thus, the preferences of the teachers are software Gran and GeoGebra, the preferences of the students are software GeoGebra and MathKit. It is noted that math teachers in determining the number of DMS, which they should know and be able to use in the future, notice 3-5 DMS and students, future math teachers, notice 5-7 DMS. Statistical processing of the results was made based on the sign test. It allowed to justify the conclusion, that the study of 5 DMS is needed, at the significance level of 0.05.

  1. Mathematical modeling and analysis of heat pipe start-up from the frozen state

    International Nuclear Information System (INIS)

    Jang, J.H.; Faghri, A.; Chang, W.S.; Mahefkey, E.T.

    1989-08-01

    The start-up process of a frozen heat pipe is described and a complete mathematical model for the start-up of the frozen heat pipe is developed based on the existing experimental data, which is simplified and solved numerically. The two-dimensional transient model for the wall and wick is coupled with the one-dimensional transient model for the vapor flow when vaporization and condensation occur at the interface. A parametric study is performed to examine the effect of the boundary specification at the surface of the outer wall on the successful start-up from the frozen state. For successful start-up, the boundary specification at the outer wall surface must melt the working substance in the condenser before dry-out takes place in the evaporator

  2. Regulatory T cell effects in antitumor laser immunotherapy: a mathematical model and analysis

    Science.gov (United States)

    Dawkins, Bryan A.; Laverty, Sean M.

    2016-03-01

    Regulatory T cells (Tregs) have tremendous influence on treatment outcomes in patients receiving immunotherapy for cancerous tumors. We present a mathematical model incorporating the primary cellular and molecular components of antitumor laser immunotherapy. We explicitly model developmental classes of dendritic cells (DCs), cytotoxic T cells (CTLs), primary and metastatic tumor cells, and tumor antigen. Regulatory T cells have been shown to kill antigen presenting cells, to influence dendritic cell maturation and migration, to kill activated killer CTLs in the tumor microenvironment, and to influence CTL proliferation. Since Tregs affect explicitly modeled cells, but we do not explicitly model dynamics of Treg themselves, we use model parameters to analyze effects of Treg immunosuppressive activity. We will outline a systematic method for assigning clinical outcomes to model simulations and use this condition to associate simulated patient treatment outcome with Treg activity.

  3. An experimental and mathematical analysis of lymphopoiesis dynamics under continuous irradiation

    International Nuclear Information System (INIS)

    Zukhbaya, T.M.; Smirnova, O.A.

    1991-01-01

    A mathematical model describing the dynamics of lymphopoiesis in mammals continuously exposed to ionizing radiation has been developed. It is based on the theory of chalone regulation of hematopoiesis. The model comprises a system of nine differential equations. Results from the model were compared with our experimental data for bone marrow and blood lymphocytes of rats continuously exposed to gamma radiation in a wide range of dose rates. The model reproduces the lymphopoiesis dynamics that we observed in our experiment, in particular, the radiation hormesis at low dose rates, the reduction of lymphopoiesis at intermediate dose rates, and extinction of lymphopoiesis at high dose rates of continuous radiation. The possible explanation of the hormesis is suggested by the framework of the model. The model can be used for predicting the lymphopoiesis dynamics in mammals under continuous irradiation

  4. Analysis of Overnight ROBOR Interbank Interest Rate Recorded in October 2008 Using a Correlational Mathematical Model

    Directory of Open Access Journals (Sweden)

    Ramona Mariana CALINICA

    2013-08-01

    Full Text Available Information about possible manipulation of the overnight Robor interbank interest rates appeared in the press in late June 2012 when the British bank Barclays was fined for manipulating Libor. Suspicion of manipulation of interest rates has not spared Romania.The purpose of this paper is to provide mathematical support persons or authorities concerned in finding out whether the overnight ROBOR reference rates from October 2008 were the result of an agreement between banks or is a natural reaction to the difficult conditions prevailing at that time, and why not, decision support to establish a intervention policies when deviations of the interbank money market parameters, in relation to a specific goal, above a certain value.

  5. Mathematical Modelling and Analysis of the Tumor Treatment Regimens with Pulsed Immunotherapy and Chemotherapy.

    Science.gov (United States)

    Pang, Liuyong; Shen, Lin; Zhao, Zhong

    2016-01-01

    To begin with, in this paper, single immunotherapy, single chemotherapy, and mixed treatment are discussed, and sufficient conditions under which tumor cells will be eliminated ultimately are obtained. We analyze the impacts of the least effective concentration and the half-life of the drug on therapeutic results and then find that increasing the least effective concentration or extending the half-life of the drug can achieve better therapeutic effects. In addition, since most types of tumors are resistant to common chemotherapy drugs, we consider the impact of drug resistance on therapeutic results and propose a new mathematical model to explain the cause of the chemotherapeutic failure using single drug. Based on this, in the end, we explore the therapeutic effects of two-drug combination chemotherapy, as well as mixed immunotherapy with combination chemotherapy. Numerical simulations indicate that combination chemotherapy is very effective in controlling tumor growth. In comparison, mixed immunotherapy with combination chemotherapy can achieve a better treatment effect.

  6. Mathematics everywhere

    CERN Document Server

    Aigner, Martin; Spain, Philip G

    2010-01-01

    Mathematics is all around us. Often we do not realize it, though. Mathematics Everywhere is a collection of presentations on the role of mathematics in everyday life, through science, technology, and culture. The common theme is the unique position of mathematics as the art of pure thought and at the same time as a universally applicable science. The authors are renowned mathematicians; their presentations cover a wide range of topics. From compact discs to the stock exchange, from computer tomography to traffic routing, from electronic money to climate change, they make the "math inside" unde

  7. Financial mathematics

    CERN Document Server

    Jothi, A Lenin

    2009-01-01

    Financial services, particularly banking and insurance services is the prominent sector for the development of a nation. After the liberalisation of financial sector in India, the scope of getting career opportunities has been widened. It is heartening to note that various universities in India have introduced professional courses on banking and insurance. A new field of applied mathematics has come into prominence under the name of Financial Mathematics. Financial mathematics has attained much importance in the recent years because of the role played by mathematical concepts in decision - m

  8. Mathematical scandals

    CERN Document Server

    Pappas, Theoni

    1997-01-01

    In this highly readable volume of vignettes of mathematical scandals and gossip, Theoni Pappas assembles 29 fascinating stories of intrigue and the bizarre ? in short, the human background of the history of mathematics. Might a haberdasher have changed Einstein's life? Why was the first woman mathematician murdered? How come there's no Nobel Prize in mathematics?Mathematics is principally about numbers, equations, and solutions, all of them precise and timeless. But, behind this arcane matter lies the sometimes sordid world of real people, whose rivalries and deceptions

  9. Engineering mathematics

    CERN Document Server

    Stroud, K A

    2013-01-01

    A groundbreaking and comprehensive reference that's been a bestseller since it first debuted in 1970, the new seventh edition of Engineering Mathematics has been thoroughly revised and expanded. Providing a broad mathematical survey, this innovative volume covers a full range of topics from the very basic to the advanced. Whether you're an engineer looking for a useful on-the-job reference or want to improve your mathematical skills, or you are a student who needs an in-depth self-study guide, Engineering Mathematics is sure to come in handy time and time again.

  10. Rethinking the mathematics curriculum

    CERN Document Server

    Hoyles, Celia; Woodhouse, Geoffrey

    1998-01-01

    At a time when political interest in mathematics education is at its highest, this book demonstrates that the issues are far from straightforward. A wide range of international contributors address such questions as: What is mathematics, and what is it for? What skills does mathematics education need to provide as technology advances? What are the implications for teacher education? What can we learn from past attempts to change the mathematics curriculum? Rethinking the Mathematics Curriculum offers stimulating discussions, showing much is to be learnt from the differences in culture, national expectations, and political restraints revealed in the book. This accessible book will be of particular interest to policy makers, curriculum developers, educators, researchers and employers as well as the general reader.

  11. The Analysis of Proportional Reasoning Problem in the Indonesian Mathematics Textbook for Junior High School

    Directory of Open Access Journals (Sweden)

    Rahmah Johar

    2017-06-01

    Full Text Available The lack of Indonesian students achievement in the international assessment is due to several factors. Students are not familiar with the problems requiring reasoning, in particular the proportional reasoning. This research aims to identify the distribution and the Level of Cognitive Demands (LCD of the proportional reasoning problems found in the Year 7 and Year 8 mathematics textbooks based on the 2013 curriculum (revised edition 2014. The data collection was conducted by identifying the proportional reasoning problems found in the whole chapters of the textbooks which are then analysed and classified using the Smiths and Stein’s criteria of LCD (1998. The results reveal that the proportional reasoning problems were only found in the three of 17 chapters namely ratio and proportion, rectangle and triangle, and Pythagorean Theorem, which represent different LCD including Lower-LCD (Low-M and Low-P and Higher-LCD (High-P. Out of 69 proportional reasoning problem found in the textbooks, the percentage of higher-LCD problems (n=29 ; 42.03% is less than lower-LCD (n=40;57.97%. In addition, the higher-LCD problems found were only the high-P type. None was found to meet the requirement of High-DM demanding students to conduct ‘doing mathematics’, complex approach and self-monitoring or self regulation of students’ cognitive process. It is recommended that the proportional reasoning problems, including some High-DM problems, should be provided in each topic in Indonesian mathematics textbooks.

  12. Mapping and Analysis of Forest and Land Fire Potential Using Geospatial Technology and Mathematical Modeling

    International Nuclear Information System (INIS)

    Suliman, M D H; Mahmud, M; Reba, M N M; S, L W

    2014-01-01

    Forest and land fire can cause negative implications for forest ecosystems, biodiversity, air quality and soil structure. However, the implications involved can be minimized through effective disaster management system. Effective disaster management mechanisms can be developed through appropriate early warning system as well as an efficient delivery system. This study tried to focus on two aspects, namely by mapping the potential of forest fire and land as well as the delivery of information to users through WebGIS application. Geospatial technology and mathematical modeling used in this study for identifying, classifying and mapping the potential area for burning. Mathematical models used is the Analytical Hierarchy Process (AHP), while Geospatial technologies involved include remote sensing, Geographic Information System (GIS) and digital field data collection. The entire Selangor state was chosen as our study area based on a number of cases have been reported over the last two decades. AHP modeling to assess the comparison between the three main criteria of fuel, topography and human factors design. Contributions of experts directly involved in forest fire fighting operations and land comprising officials from the Fire and Rescue Department Malaysia also evaluated in this model. The study found that about 32.83 square kilometers of the total area of Selangor state are the extreme potential for fire. Extreme potential areas identified are in Bestari Jaya and Kuala Langat High Ulu. Continuity of information and terrestrial forest fire potential was displayed in WebGIS applications on the internet. Display information through WebGIS applications is a better approach to help the decision-making process at a high level of confidence and approximate real conditions. Agencies involved in disaster management such as Jawatankuasa Pengurusan Dan Bantuan Bencana (JPBB) of District, State and the National under the National Security Division and the Fire and Rescue

  13. Mapping and Analysis of Forest and Land Fire Potential Using Geospatial Technology and Mathematical Modeling

    Science.gov (United States)

    Suliman, M. D. H.; Mahmud, M.; Reba, M. N. M.; S, L. W.

    2014-02-01

    Forest and land fire can cause negative implications for forest ecosystems, biodiversity, air quality and soil structure. However, the implications involved can be minimized through effective disaster management system. Effective disaster management mechanisms can be developed through appropriate early warning system as well as an efficient delivery system. This study tried to focus on two aspects, namely by mapping the potential of forest fire and land as well as the delivery of information to users through WebGIS application. Geospatial technology and mathematical modeling used in this study for identifying, classifying and mapping the potential area for burning. Mathematical models used is the Analytical Hierarchy Process (AHP), while Geospatial technologies involved include remote sensing, Geographic Information System (GIS) and digital field data collection. The entire Selangor state was chosen as our study area based on a number of cases have been reported over the last two decades. AHP modeling to assess the comparison between the three main criteria of fuel, topography and human factors design. Contributions of experts directly involved in forest fire fighting operations and land comprising officials from the Fire and Rescue Department Malaysia also evaluated in this model. The study found that about 32.83 square kilometers of the total area of Selangor state are the extreme potential for fire. Extreme potential areas identified are in Bestari Jaya and Kuala Langat High Ulu. Continuity of information and terrestrial forest fire potential was displayed in WebGIS applications on the internet. Display information through WebGIS applications is a better approach to help the decision-making process at a high level of confidence and approximate real conditions. Agencies involved in disaster management such as Jawatankuasa Pengurusan Dan Bantuan Bencana (JPBB) of District, State and the National under the National Security Division and the Fire and Rescue

  14. An Analysis of the Reasoning Skills of Pre-Service Teachers in the Context of Mathematical Thinking

    Science.gov (United States)

    Yavuz Mumcu, Hayal; Aktürk, Tolga

    2017-01-01

    The aim of this study is to address and analyse pre-service teachers' mathematical reasoning skills in relation to mathematical thinking processes. For these purposes, pre-service teachers' mathematical reasoning skills namely generalising/abstraction/modelling, ratiocination, development and creative thinking skills and the relationships among…

  15. Connecting Mathematics and Literature: An Analysis of Pre-Service Elementary School Teachers' Changing Beliefs and Knowledge

    Science.gov (United States)

    Wilburne, Jane M.; Napoli, Mary

    2008-01-01

    The National Council of Teachers of Mathematics calls for students to see relationships and connections with mathematics (2000). This study examined the influences on eight pre-service elementary school teachers' beliefs and knowledge of teaching mathematics through literature. The semester long project involved both the language arts and…

  16. Why Teach mathematics to Adults?

    DEFF Research Database (Denmark)

    Johansen, Lene Østergaard

    2008-01-01

    teachers. I distinguish analytically between three different discourses. The Political Discourse, The Curriculum Planner Discourse and The Mathematics Teachers Discourse. The discourses are analysed separately and I distinguish between explicit reasons and implicit reasons.       In the thesis I construct...... a framework or a tool for my analysis of the three discourses, which consists of three elements. I identify the explicit reasons asking the question "Why teach mathematics to adults?" to the texts of each discourse. To identify the implicit reasons, I assume that it is necessary to construct a need...... in all areas of life increases considerably with good (functional/basic) numeracy skills.    The analysis of the implicit reasons shows that the politicians construct a need for education through the way they talk about the demands of the labour market, the demands of the educational system, the demands...

  17. Mathematical analysis and algorithms for efficiently and accurately implementing stochastic simulations of short-term synaptic depression and facilitation

    Directory of Open Access Journals (Sweden)

    Mark D McDonnell

    2013-05-01

    Full Text Available The release of neurotransmitter vesicles after arrival of a pre-synaptic action potential at cortical synapses is known to be a stochastic process, as is the availability of vesicles for release. These processes are known to also depend on the recent history of action-potential arrivals, and this can be described in terms of time-varying probabilities of vesicle release. Mathematical models of such synaptic dynamics frequently are based only on the mean number of vesicles released by each pre-synaptic action potential, since if it is assumed there are sufficiently many vesicle sites, then variance is small. However, it has been shown recently that variance across sites can be significant for neuron and network dynamics, and this suggests the potential importance of studying short-term plasticity using simulations that do generate trial-to-trial variability. Therefore, in this paper we study several well-known conceptual models for stochastic availability and release. We state explicitly the random variables that these models describe and propose efficient algorithms for accurately implementing stochastic simulations of these random variables in software or hardware. Our results are complemented by mathematical analysis and statement of pseudo-code algorithms.

  18. Indicators that influence prospective mathematics teachers representational and reasoning abilities

    Science.gov (United States)

    Darta; Saputra, J.

    2018-01-01

    Representational and mathematical reasoning ability are very important ability as basic in mathematics learning process. The 2013 curriculum suggests that the use of a scientific approach emphasizes higher order thinking skills. Therefore, a scientific approach is required in mathematics learning to improve ability of representation and mathematical reasoning. The objectives of this research are: (1) to analyze representational and reasoning abilities, (2) to analyze indicators affecting the ability of representation and mathematical reasoning, (3) to analyze scientific approaches that can improve the ability of representation and mathematical reasoning. The subject of this research is the students of mathematics prospective teachers in the first semester at Private Higher Education of Bandung City. The research method of this research was descriptive analysis. The research data were collected using reasoning and representation tests on sixty-one students. Data processing was done by descriptive analysis specified based on the indicators of representation ability and mathematical reasoning that influenced it. The results of this first-year study showed that students still had many weaknesses in reasoning and mathematical representation that were influenced by the ability to understand the indicators of both capabilities. After observing the results of the first-year research, then in the second and third year, the development of teaching materials with a scientific approach in accordance with the needs of prospective students was planned.

  19. [Efficient Pharmaceutical Formulation Designs and Their Development Using Mathematical and Statistical Analysis].

    Science.gov (United States)

    Iwao, Yasunori

    2015-01-01

    With the aim of directly predicting the functionality and mechanism of pharmaceutical excipients, we investigated an analysis method based on available surface area (S(t)), which is the surface area of a drug in direct contact with the external solvent during dissolution. First, to study the effect of lubricant concentration on the dissolution rate of acetaminophen (APAP), the dissolution behaviors as well as the change over time in S(t) of APAP tablets were examined. In the dissolution tests, a retarded dissolution of APAP was not observed with new lubricant triglycerin full behenate (TR-FB), whereas magnesium stearate (Mg-St) retarded the dissolution. The S(t) profiles for APAP with Mg-St at>0.5% showed downward curvature indicating a gradual decrease in surface area over time. Conversely, with TR-FB, even when its concentration was increased, the S(t) profile for APAP had a maximum value. The differences between Mg-St and TR-FB could be explained by the differences in extensibility deriving from their morphology. Next, we evaluated the effect of disintegtant concentration using five disintegrants. When disintegrant was added to ethenzamide tablet formulation, an increase in the dissolution rate and S(t) dependent on disintegrant concentration was observed, according to the type of disintegrant. It was found that the water absorption ability of disintegrants had strong correlations with the parameters of S(t). Taken together, this study demonstrates that analysis of S(t) can directly provide useful information, especially about the functionality of pharmaceutical excipients.

  20. Dynamic analysis of the PEC fast reactor vessel: On-site tests and mathematical models

    International Nuclear Information System (INIS)

    Zola, M.; Martelli, A.; Masoni, P.; Scandola, G.

    1988-01-01

    This paper presents the main features and results of the on-site dynamic tests and the related numerical analyses carried out for the PEC reactor vessel. The purpose is to provide an example of on-site testing of large components, stressing the problems encountered during the experiments, as well as in the processing phase of the test results and for the comparisons between calculations and measurements. Tests, performed by ISMES on behalf of ENEA, allowed the dynamic response of the empty vessel to be measured, thus providing data for the verification of the numerical models of the vessel supporting structure adopted in the PEC reactor-block seismic analysis. An axisymmetric model of the vessel, implemented in the NOVAX code, had been developed in the framework of the detailed numerical studies performed by NOVATOME (again on behalf of ENEA), to check the beam schematization with fluid added mass model adopted by ANSALDO in SAP-IV and ANSYS for the reactor-block design calculations. Furthermore, a numerical model, describing vessel supporting structure in detail, was also developed by ANSALDO and implemented in the SAP-IV code. The test conditions were analysed by use of these and the design models. Comparisons between calculations and measurements showed particularly good agreement with regard to first natural frequency of the vessel and rocking stiffness of the vessel supporting structure, i.e. those parameters on which vessel seismic amplification mainly depends: this demonstrated the adequacy of the design analysis to correctly calculate the seismic motion at the PEC core diagrid. (author). 5 refs, 23 figs, 4 tabs

  1. Panel Debate: Technics and technology in mathematics and mathematics education

    DEFF Research Database (Denmark)

    Misfeldt, Morten

    2015-01-01

    The use of computer technology for teaching and learning of mathematics has several consequences and does sometimes give rise to both controversies and misunderstandings. We address these problems by both a philosophical and a historical approach, investigating what it actually is that goes on when...... guidelines and conclusions regarding the use of computer technology in mathematics education....... new technologies enter mathematics as a discipline and mathematics education as a societal practice. Our analysis suggests a focus on continuities in time and place in the sense that it is necessary to understand the history of “tool use” in mathematics and the various ways that scholastic and non...

  2. Mathematical analysis of the impact mechanism of information platform on agro-product supply chain and agro-product competitiveness

    Directory of Open Access Journals (Sweden)

    Jiang Qi-Jie

    2017-04-01

    Full Text Available How to optimize agro-product supply chain to promote its operating efficiency so as to enhance the competitiveness of regional agricultural products has posed a problem to academic circles, business circles and governments of various levels. One way to solve this problem is to introduce an information platform into the supply chain, which this essay focuses on. Firstly, a review of existing research findings concerning the agro-product competitiveness, agro-product supply chain (ASC and information platform was given. Secondly, we constructed a mathematical model to analyze the impact of information platform on the bullwhip effect in ASC. Thirdly, another mathematical model was constructed to help compare and analyze the impact of information platform on information acquisition of members in ASC. The research results show that the implantation of information platform can mitigate the bullwhip effect in ASC, and members can determine order amount or production more close to the actual market demand. And also the information platform can reduce the time for members in ASC to get information from other members. Besides, information platform can help ASC to alleviate information asymmetry among upstream and downstream members. Furthermore, researches about the operating mechanism and pattern, technical feature and running structure of the information platform, along with their impacts on agro-product supply chain and the competitiveness of agricultural products need to be advanced.

  3. The Analysis of Geometrical Reasoning Ability Viewed from Self-Efficacy on Connected Mathematic Project (CMP Learning Etnomathematics-Based

    Directory of Open Access Journals (Sweden)

    Desi Dwi Damaryanti

    2017-11-01

    Full Text Available The purpose of this research was to know the geometrical reasoning ability of the students viewed from the self-efficacy through the learning of  Connected Mathematic Project (CMP ethnomathematic-based. The type of this research was qualitative which was descriptive. To obtained the validity of the qualitative data, the checking technique used in this research was sources triangulation, which had been done by comparing the suitability of the obtained data from the results of the interview and the test. Population of this research was the students of grade VIII at SMP Negeri 1 Sidoharjo and the sample was the students from VIII A Class. At the final, 12 research subjects were chosen to represent the group of level 1 self-efficacy, level 2 self-efficacy, level 3 self-efficacy, level 4 self efficacy, level 5 self-efficacy, and level 6 self-efficacy. In this research, there was a finding which shows us that the students with high self-efficacy had low ability to finish the geometrical reasoning ability test, while the students with low self-efficacy had the ability to finish the geometrical reasoning ability test. The factors which affected the finding were the motivations and the interest of learning mathematics which was affecting the attitude of the students in the classroom.

  4. Mathematical analysis of the impact mechanism of information platform on agro-product supply chain and agro-product competitiveness

    Science.gov (United States)

    Jiang, Qi-Jie; Jin, Mao-Zhu; Ren, Pei-Yu

    2017-04-01

    How to optimize agro-product supply chain to promote its operating efficiency so as to enhance the competitiveness of regional agricultural products has posed a problem to academic circles, business circles and governments of various levels. One way to solve this problem is to introduce an information platform into the supply chain, which this essay focuses on. Firstly, a review of existing research findings concerning the agro-product competitiveness, agro-product supply chain (ASC) and information platform was given. Secondly, we constructed a mathematical model to analyze the impact of information platform on the bullwhip effect in ASC. Thirdly, another mathematical model was constructed to help compare and analyze the impact of information platform on information acquisition of members in ASC. The research results show that the implantation of information platform can mitigate the bullwhip effect in ASC, and members can determine order amount or production more close to the actual market demand. And also the information platform can reduce the time for members in ASC to get information from other members. Besides, information platform can help ASC to alleviate information asymmetry among upstream and downstream members. Furthermore, researches about the operating mechanism and pattern, technical feature and running structure of the information platform, along with their impacts on agro-product supply chain and the competitiveness of agricultural products need to be advanced.

  5. Applied impulsive mathematical models

    CERN Document Server

    Stamova, Ivanka

    2016-01-01

    Using the theory of impulsive differential equations, this book focuses on mathematical models which reflect current research in biology, population dynamics, neural networks and economics. The authors provide the basic background from the fundamental theory and give a systematic exposition of recent results related to the qualitative analysis of impulsive mathematical models. Consisting of six chapters, the book presents many applicable techniques, making them available in a single source easily accessible to researchers interested in mathematical models and their applications. Serving as a valuable reference, this text is addressed to a wide audience of professionals, including mathematicians, applied researchers and practitioners.

  6. A Mathematical Pressure Transient Analysis Model for Multiple Fractured Horizontal Wells in Shale Gas Reservoirs

    Directory of Open Access Journals (Sweden)

    Yan Zeng

    2018-01-01

    Full Text Available Multistage fractured horizontal wells (MFHWs have become the main technology for shale gas exploration. However, the existing models have neglected the percolation mechanism in nanopores of organic matter and failed to consider the differences among the reservoir properties in different areas. On that account, in this study, a modified apparent permeability model was proposed describing gas flow in shale gas reservoirs by integrating bulk gas flow in nanopores and gas desorption from nanopores. The apparent permeability was introduced into the macroseepage model to establish a dynamic pressure analysis model for MFHWs dual-porosity formations. The Laplace transformation and the regular perturbation method were used to obtain an analytical solution. The influences of fracture half-length, fracture permeability, Langmuir volume, matrix radius, matrix permeability, and induced fracture permeability on pressure and production were discussed. Results show that fracture half-length, fracture permeability, and induced fracture permeability exert a significant influence on production. A larger Langmuir volume results in a smaller pressure and pressure derivative. An increase in matrix permeability increases the production rate. Besides, this model fits the actual field data relatively well. It has a reliable theoretical foundation and can preferably describe the dynamic changes of pressure in the exploration process.

  7. Mathematical logic

    CERN Document Server

    Kleene, Stephen Cole

    1967-01-01

    Undergraduate students with no prior instruction in mathematical logic will benefit from this multi-part text. Part I offers an elementary but thorough overview of mathematical logic of 1st order. Part II introduces some of the newer ideas and the more profound results of logical research in the 20th century. 1967 edition.

  8. Making Mathematics.

    Science.gov (United States)

    Huckstep, Peter

    2002-01-01

    Contends teachers must resist the temptation to suggest that, while children can create stories and melodies, they cannot create mathematics. Quotes mathematician G. H. Hardy: "A mathematician, like a painter or poet, is a 'maker' of patterns." Considers mathematics should be able to stand up for itself. (BT)

  9. Mathematical psychology.

    Science.gov (United States)

    Batchelder, William H

    2010-09-01

    Mathematical psychology is a sub-field of psychology that started in the 1950s and has continued to grow as an important contributor to formal psychological theory, especially in the cognitive areas of psychology such as learning, memory, classification, choice response time, decision making, attention, and problem solving. In addition, there are several scientific sub-areas that were originated by mathematical psychologists such as the foundations of measurement, stochastic memory models, and psychologically motivated reformulations of expected utility theory. Mathematical psychology does not include all uses of mathematics and statistics in psychology, and indeed there is a long history of such uses especially in the areas of perception and psychometrics. What is most unique about mathematical psychology is its approach to theory construction. While accepting the behaviorist dictum that the data in psychology must be observable and replicable, mathematical models are specified in terms of unobservable formal constructs that can predict detailed aspects of data across multiple experimental and natural settings. By now almost all the substantive areas of cognitive and experimental psychology have formal mathematical models and theories, and many of these are due to researchers that identify with mathematical psychology. Copyright © 2010 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website. Copyright © 2010 John Wiley & Sons, Ltd.

  10. Mathematics 2

    CERN Document Server

    Kodaira, Kunihiko

    1996-01-01

    This is the translation from the Japanese textbook for the grade 11 course, "General Mathematics". It is part of the easier of the three elective courses in mathematics offered at this level and is taken by about 40% of students. The book covers basic notions of probability and statistics, vectors, exponential, logarithmic, and trigonometric functions, and an introduction to differentiation and integration.

  11. Mapping Mathematics in Classroom Discourse

    Science.gov (United States)

    Herbel-Eisenmann, Beth A.; Otten, Samuel

    2011-01-01

    This article offers a particular analytic method from systemic functional linguistics, "thematic analysis," which reveals the mathematical meaning potentials construed in discourse. Addressing concerns that discourse analysis is too often content-free, thematic analysis provides a way to represent semantic structures of mathematical content,…

  12. Toward the Nexus Equation: A Conceptual and Mathematical Framework for Energy-Water-Food Nexus Analysis

    Science.gov (United States)

    Higgins, C. W.; Abou Najm, M.

    2015-12-01

    Water, energy, and agriculture depend on each other so strongly that attempts to achieve sustainability in any of those three domains will directly impact the others. These interdependencies, collectively known as the Water-Energy-Food Nexus, become more complex and more critical as the climate changes, the population grows, habits and lifestyle alternatives, and the prices of water, energy, and food increase. The U.S. National Intelligence Council has identified the nexus of water, energy, food, and climate change as one of four overarching megatrends that will shape the world in 2030. However, the global research community has rarely addressed the full problem and focused instead on different subsets of the problem. For example, interactions between two of the three domains were studied, often neglecting the impact of such interaction on the third domain. Investigators have quantified water-energy tradeoffs in the highly engineered, centralized systems of water and power management. Agricultural researchers have tracked water costs by applying the concept of virtual water (the total volume of water needed to produce and process a commodity or service) or using large-scale system models to investigate food and water security. Integrative nexus initiatives have focused on reviews and data collection of existing knowledge and relevant facts. They unfortunately lack a conceptual and mathematical framework that can integrate all the gathered knowledge and account for multiple interactions, feedbacks, or natural processes that occur across all three domains of the nexus. Here, we present an integrated conceptual and mathematical framework (roadmap) for the nexus. This framework is driven by spatiotemporal demands for water, energy, and food to be satisfied by resource management of the three domains, envisioned as a stepwise process, with each step requiring inputs from the three nexus domains and creating waste products. The efficiency of each step, combined with mass

  13. Discrete Mathematics

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2011-01-01

    ; construct a finite state machine for a given application. Apply these concepts to new problems. The teaching in Discrete Mathematics is a combination of sessions with lectures and students solving problems, either manually or by using Matlab. Furthermore a selection of projects must be solved and handed...... to accomplish the following: -Understand and apply formal representations in discrete mathematics. -Understand and apply formal representations in problems within discrete mathematics. -Understand methods for solving problems in discrete mathematics. -Apply methods for solving problems in discrete mathematics...... to new problems. Relations and functions: Define a product set; define and apply equivalence relations; construct and apply functions. Apply these concepts to new problems. Natural numbers and induction: Define the natural numbers; apply the principle of induction to verify a selection of properties...

  14. Mathematics unbound

    CERN Document Server

    Parshall, Karen Hunger

    2002-01-01

    Although today's mathematical research community takes its international character very much for granted, this "global nature" is relatively recent, having evolved over a period of roughly 150 years-from the beginning of the nineteenth century to the middle of the twentieth century. During this time, the practice of mathematics changed from being centered on a collection of disparate national communities to being characterized by an international group of scholars for whom the goal of mathematical research and cooperation transcended national boundaries. Yet, the development of an international community was far from smooth and involved obstacles such as war, political upheaval, and national rivalries. Until now, this evolution has been largely overlooked by historians and mathematicians alike. This book addresses the issue by bringing together essays by twenty experts in the history of mathematics who have investigated the genesis of today's international mathematical community. This includes not only develo...

  15. Mathematical Methods in Wave Propagation: Part 2--Non-Linear Wave Front Analysis

    Science.gov (United States)

    Jeffrey, Alan

    1971-01-01

    The paper presents applications and methods of analysis for non-linear hyperbolic partial differential equations. The paper is concluded by an account of wave front analysis as applied to the piston problem of gas dynamics. (JG)

  16. Mathematical analysis and numerical simulation of patterns in fractional and classical reaction-diffusion systems

    International Nuclear Information System (INIS)

    Owolabi, Kolade M.

    2016-01-01

    The aim of this paper is to examine pattern formation in the sub— and super-diffusive scenarios and compare it with that of classical or standard diffusive processes in two-component fractional reaction-diffusion systems that modeled a predator-prey dynamics. The focus of the work concentrates on the use of two separate mathematical techniques, we formulate a Fourier spectral discretization method as an efficient alternative technique to solve fractional reaction-diffusion problems in higher-dimensional space, and later advance the resulting systems of ODEs in time with the adaptive exponential time-differencing solver. Obviously, the fractional Fourier approach is able to achieve spectral convergence up to machine precision regardless of the fractional order α, owing to the fact that our approach is able to give full diagonal representation of the fractional operator. The complexity of the dynamics in this system is theoretically discussed and graphically displayed with some examples and numerical simulations in one, two and three dimensions.

  17. Material degradation due to moisture and temperature. Part 1: mathematical model, analysis, and analytical solutions

    Science.gov (United States)

    Xu, C.; Mudunuru, M. K.; Nakshatrala, K. B.

    2016-11-01

    The mechanical response, serviceability, and load-bearing capacity of materials and structural components can be adversely affected due to external stimuli, which include exposure to a corrosive chemical species, high temperatures, temperature fluctuations (i.e., freezing-thawing), cyclic mechanical loading, just to name a few. It is, therefore, of paramount importance in several branches of engineering—ranging from aerospace engineering, civil engineering to biomedical engineering—to have a fundamental understanding of degradation of materials, as the materials in these applications are often subjected to adverse environments. As a result of recent advancements in material science, new materials such as fiber-reinforced polymers and multi-functional materials that exhibit high ductility have been developed and widely used, for example, as infrastructural materials or in medical devices (e.g., stents). The traditional small-strain approaches of modeling these materials will not be adequate. In this paper, we study degradation of materials due to an exposure to chemical species and temperature under large strain and large deformations. In the first part of our research work, we present a consistent mathematical model with firm thermodynamic underpinning. We then obtain semi-analytical solutions of several canonical problems to illustrate the nature of the quasi-static and unsteady behaviors of degrading hyperelastic solids.

  18. Mathematical model and characteristic analysis of hybrid photovoltaic/piezoelectric actuation mechanism

    Science.gov (United States)

    Jiang, Jing; Li, Xiaonan; Ding, Jincheng; Yue, Honghao; Deng, Zongquan

    2016-12-01

    Photovoltaic materials can turn light energy into electric energy directly, and thus have the advantages of high electrical output voltages and the ability to realize remote or non-contact control. When high-energy ultraviolet light illuminates polarized PbLaZrTi (PLZT) materials, high photovoltages will be generated along the spontaneous polarization direction due to the photovoltaic effect. In this paper, a novel hybrid photovoltaic/piezoelectric actuation mechanism is proposed. PLZT ceramics are used as a photovoltaic generator to drive a piezoelectric actuator. A mathematical model is established to define the time history of the actuation voltage between two electrodes of the piezoelectric actuator, which is experimentally validated by the test results of a piezoelectric actuator with different geometrical parameters under irradiation at different light intensities. Some important characteristics of this novel actuation mechanism are analyzed and it can be concluded that (1) it is experimentally validated that there is no hysteresis between voltage and deformation which exists in a PLZT actuator; (2) the saturated voltage and response speed can be improved by using a multi-patch PLZT generator to drive the piezoelectric actuator; and (3) the initial voltage of the piezoelectric actuator can be acquired by controlling the logical switch between the PLZT and the piezoelectric actuator while the initial voltages increase with the rise of light intensity.

  19. Mathematical and numerical analysis of a few hydrodynamic and kinetic models of plasma physics

    International Nuclear Information System (INIS)

    Buet, C.

    2005-01-01

    My research work deals mainly with the mathematical modelling and the numerical simulation of plasma physics. This document is divided into 3 parts. The first one is a summary of the works done for the numerical solving of collision operators. The common thread of this part is obtaining numerical schemes preserving operators' properties namely physical invariants like mass, momentum and energy, equilibrium states and entropy decrease. These properties are generally checked formally for continuous operators, may give rise to some difficulties for discrete operators. In the second part I present a summary of the works regarding moments methods applied to radiative transfer and the numerical issues dealing with their discretization. The common thread of this part is how to get numerical schemes preserving asymptotic scattering and invariant domains for Lorentz models and also for non-linear telegraph-type equations involved in radiative transfer or electronic plasma. In the third part I present 2 themes linked to collision operators: multi-fluid ionization and the non-existence of linear monotone schemes for some linear parabolic equations

  20. Analysis on Experimental Investigation and Mathematical Modeling of Incompressible Flow Through Ceramic Foam Filters

    Science.gov (United States)

    Akbarnejad, Shahin; Jonsson, Lage Tord Ingemar; Kennedy, Mark William; Aune, Ragnhild Elizabeth; Jönsson, Pӓr Göran

    2016-08-01

    This paper presents experimental results of pressure drop measurements on 30, 50, and 80 pores per inch (PPI) commercial alumina ceramic foam filters (CFF) and compares the obtained pressure drop profiles to numerically modeled values. In addition, it is aimed at investigating the adequacy of the mathematical correlations used in the analytical and the computational fluid dynamics (CFD) simulations. It is shown that the widely used correlations for predicting pressure drop in porous media continuously under-predict the experimentally obtained pressure drop profiles. For analytical predictions, the negative deviations from the experimentally obtained pressure drop using the unmodified Ergun and Dietrich equations could be as high as 95 and 74 pct, respectively. For the CFD predictions, the deviation to experimental results is in the range of 84.3 to 88.5 pct depending on filter PPI. Better results can be achieved by applying the Forchheimer second-order drag term instead of the Brinkman-Forchheimer drag term. Thus, the final deviation of the CFD model estimates lie in the range of 0.3 to 5.5 pct compared to the measured values.

  1. Comparative analysis of different methods in mathematical modelling of the recuperative heat exchangers

    International Nuclear Information System (INIS)

    Debeljkovic, D.Lj.; Stevic, D.Z.; Simeunovic, G.V.; Misic, M.A.

    2015-01-01

    The heat exchangers are frequently used as constructive elements in various plants and their dynamics is very important. Their operation is usually controlled by manipulating inlet fluid temperatures or mass flow rates. On the basis of the accepted and critically clarified assumptions, a linearized mathematical model of the cross-flow heat exchanger has been derived, taking into account the wall dynamics. The model is based on the fundamental law of energy conservation, covers all heat accumulation storages in the process, and leads to the set of partial differential equations (PDE), which solution is not possible in closed form. In order to overcome the solutions difficulties in this paper are analyzed different methods for modeling the heat exchanger: approach based on Laplace transformation, approximation of partial differential equations based on finite differences, the method of physical discretization and the transport approach. Specifying the input temperatures and output variables, under the constant initial conditions, the step transient responses have been simulated and presented in graphic form in order to compare these results for the four characteristic methods considered in this paper, and analyze its practical significance. (author)

  2. Mathematical basis for the measurement of absolute and fractional cardiac output with diffusible tracers by compartmental analysis methods

    International Nuclear Information System (INIS)

    Charkes, N.D.

    1984-01-01

    Using compartmental analysis methods, a mathematical basis is given for the measurement of absolute and fractional cardiac output with diffusible tracers. Cardiac output is shown to be the product of the blood volume and the sum of the rate constants of tracer egress from blood, modified by a factor reflecting transcapillary diffusibility, the transfer fraction. The return of tracer to the blood and distant (intracellular) events are shown to play no role in the solution. Fractional cardiac output is the ratio of the rate constant of tracer egress from blood to an organ, divided by the sum of the egress constants from blood. Predominantly extracellular ions such as sodium or bromide are best suited for this technique, although theoretically any diffusible tracer whose compartmental model can be solved may be used. It is shown that fractional cardiac output is independent of the transfer fraction, and therefore can be measured accurately by tracers which are not freely diffusible

  3. A Comprehensive Mathematical Programming Model for Minimizing Costs in A Multiple-Item Reverse Supply Chain with Sensitivity Analysis

    Directory of Open Access Journals (Sweden)

    Mahmoudi Hoda

    2014-09-01

    Full Text Available These instructions give you guidelines for preparing papers for IFAC conferences. A reverse supply chain is configured by a sequence of elements forming a continuous process to treat return-products until they are properly recovered or disposed. The activities in a reverse supply chain include collection, cleaning, disassembly, test and sorting, storage, transport, and recovery operations. This paper presents a mathematical programming model with the objective of minimizing the total costs of reverse supply chain including transportation, fixed opening, operation, maintenance and remanufacturing costs of centers. The proposed model considers the design of a multi-layer, multi-product reverse supply chain that consists of returning, disassembly, processing, recycling, remanufacturing, materials and distribution centers. This integer linear programming model is solved by using Lingo 9 software and the results are reported. Finally, a sensitivity analysis of the proposed model is also presented.

  4. Developing a Study Orientation Questionnaire in Mathematics for primary school students.

    Science.gov (United States)

    Maree, Jacobus G; Van der Walt, Martha S; Ellis, Suria M

    2009-04-01

    The Study Orientation Questionnaire in Mathematics (Primary) is being developed as a diagnostic measure for South African teachers and counsellors to help primary school students improve their orientation towards the study of mathematics. In this study, participants were primary school students in the North-West Province of South Africa. During the standardisation in 2007, 1,013 students (538 boys: M age = 12.61; SD = 1.53; 555 girls: M age = 11.98; SD = 1.35; 10 missing values) were assessed. Factor analysis yielded three factors. Analysis also showed satisfactory reliability coefficients and item-factor correlations. Step-wise linear regression indicated that three factors (Mathematics anxiety, Study attitude in mathematics, and Study habits in mathematics) contributed significantly (R2 = .194) to predicting achievement in mathematics as measured by the Basic Mathematics Questionnaire (Primary).

  5. Mathematical and numerical analysis of a multi-velocity multi-fluid model for interpenetration of miscible fluids

    International Nuclear Information System (INIS)

    Enaux, C.

    2007-11-01

    The simulation of indirect laser implosion requires an accurate knowledge of the inter-penetration of the laser target materials turned into plasma. This work is devoted to the study of a multi-velocity multi-fluid model recently proposed by Scannapieco and Cheng (SC) to describe the inter-penetration of miscible fluids. In this document, we begin with presenting the SC model in the context of miscible fluids flow modelling. Afterwards, the mathematical analysis of the model is carried out (study of the hyperbolicity, existence of a strictly convex mathematical entropy, asymptotic analysis and diffusion limit). As a conclusion the problem is well set. Then, we focus on the problem of numerical resolution of systems of conservation laws with a relaxation source term, because SC model belongs to this class. The main difficulty of this task is to capture on a coarse grid the asymptotic behaviour of the system when the source term is stiff. The main contribution of this work lies in the proposition of a new technique, allowing us to construct a Lagrangian numerical flux taking into account the presence of the source term. This technique is applied first on the model-problem of a one-dimensional Euler system with friction, and then on the multi-fluid SC model. In both cases, we prove that the new scheme is asymptotic-preserving and entropic under a CFL-like condition. The two-dimensional extension of the scheme is done by using a standard alternate directions method. Some numerical results highlight the contribution of the new flux, compared with a standard Lagrange plus Remap scheme where the source term is processed using an operator splitting. (author)

  6. Mathematical modeling and statistical analysis of calcium-regulated insulin granule exocytosis in ß-cells from mice and humans

    DEFF Research Database (Denmark)

    Pedersen, Morten Gram; Cortese, Giuliana; Eliasson, Lena

    2011-01-01

    Insulin is released from pancreatic ß-cells as a result of Ca2+-evoked exocytosis of dense-core granules. Secretion is biphasic, which has been suggested to correspond to the release of different granule pools. Here we review and carefully reanalyze previously published patch-clamp data on depola......Insulin is released from pancreatic ß-cells as a result of Ca2+-evoked exocytosis of dense-core granules. Secretion is biphasic, which has been suggested to correspond to the release of different granule pools. Here we review and carefully reanalyze previously published patch-clamp data...... on depolarization-evoked Ca2+-currents and corresponding capacitance measurements. Using a statistical mixed-effects model, we show that the data indicate that pool depletion is negligible in response to short depolarizations in mouse ß-cells. We then review mathematical models of granule dynamics and exocytosis...

  7. A mathematical model for the motion analysis of embedded straight microcantilevers under a pressure-driven flow

    International Nuclear Information System (INIS)

    Ezkerra, A; Mayora, K; Ruano-López, J M; Wilson, P A

    2008-01-01

    A mathematical model that estimates the deflection of straight microcantilevers embedded in a microchannel under a pressure-driven flow at low Reynolds numbers is presented. The model makes use of the Schwarz–Christoffel mapping in order to couple the geometry of the structure and the flow passing around it. Therefore, it allows the determination of the most influential parameters and suitable modifications in order to achieve the desired performance. The model does not require specific knowledge of the flow conditions in the vicinity of the structure, which improves its practical use during the early stages of design. Estimations have been made for two straight cantilevers under a range of pressures. The results obtained show good agreement with measurements from experiments

  8. Analysis of students’ creative thinking level in problem solving based on national council of teachers of mathematics

    Science.gov (United States)

    Hobri; Suharto; Rifqi Naja, Ahmad

    2018-04-01

    This research aims to determine students’ creative thinking level in problem solving based on NCTM in function subject. The research type is descriptive with qualitative approach. Data collection methods which were used are test and interview. Creative thinking level in problem solving based on NCTM indicators consists of (1) Make mathematical model from a contextual problem and solve the problem, (2) Solve problem using various possible alternatives, (3) Find new alternative(s) to solve the problem, (4) Determine the most efficient and effective alternative for that problem, (5) Review and correct mistake(s) on the process of problem solving. Result of the research showed that 10 students categorized in very satisfying level, 23 students categorized in satisfying level and 1 students categorized in less satisfying level. Students in very satisfying level meet all indicators, students in satisfying level meet first, second, fourth, and fifth indicator, while students in less satisfying level only meet first and fifth indicator.

  9. ANALYZING THE MATHEMATICAL DISPOSITION AND ITS CORRELATION WITH MATHEMATICS ACHIEVEMENT OF ABSTRACT SENIOR HIGH SCHOOL STUDENTS

    Directory of Open Access Journals (Sweden)

    Louise M. Saija

    2012-09-01

    Full Text Available Salah satu standar yang diberikan oleh National Council of Teachers of Mathematics (NCTM adalah disposisi matematik. Disposisi  bukan sekedar merujuk pada sikap tetapi suatu kecenderungan untuk berpikir dan bersikap dalam cara yang positif. Penelitian ini bertujuan untuk menganalisa disposisi matematik dan hubungannya dengan hasil belajar matematika siswa-siswa sekolah menengah atas (SMA. Sampel pada penelitian ini adalah 149 siswa SMA di Bandung. Analisa statistik didasarkan pada korelasi peringkat Spearman dan uji-t. Ditemukan bahwa secara rata-rata,  disposisi matematik dari siswa-siswa SMA dikategorikan rendah. Selanjutnya, terdapat korelasi positif dan signifikan antara disposisi matematik dan hasil belajar matematika siswa-siswa SMA, walaupun nilai koefisien korelasinya tidak tinggi. Suatu observasi juga dilakukan untuk menganalisa hubungan ini, dan didapati bahwa walaupun beberapa siswa memiliki disposisi matematik yang baik, kadang kala mereka tidak dapat menyelesaikan ujian dengan baik, karena padatnya kurikulum, dan juga aktifitas sosial mereka, yang membuat hasil belajar matematika mereka lebih rendah. Temuan lainnya adalah bahwa siswa-siswa SMA memerlukan guru-guru matematika dengan lebih banyak strategi mengajar  agar mereka dapat memiliki disposisi matematik yang lebih baik.   Kata Kunci: Disposisi Matematik, Hasil Belajar Matematika       One of the evaluation standards given by the National Council of Teachers of Mathematics (NCTM was mathematical disposition. Disposition refers not simply to attitudes but to a tendency to think and to act in positive ways. This study aimed to analyze the mathematical disposition and its correlation with mathematics achievement of senior high school (SMA students. A total of 149 SMA students in Bandung were procured as samples. Statistical analysis was based on the Spearman rank correlation and on the t-test. The findings showed that at average, the mathematical disposition of the SMA

  10. Obtaining mathematical models for assessing efficiency of dust collectors using integrated system of analysis and data management STATISTICA Design of Experiments

    Science.gov (United States)

    Azarov, A. V.; Zhukova, N. S.; Kozlovtseva, E. Yu; Dobrinsky, D. R.

    2018-05-01

    The article considers obtaining mathematical models to assess the efficiency of the dust collectors using an integrated system of analysis and data management STATISTICA Design of Experiments. The procedure for obtaining mathematical models and data processing is considered by the example of laboratory studies on a mounted installation containing a dust collector in counter-swirling flows (CSF) using gypsum dust of various fractions. Planning of experimental studies has been carried out in order to reduce the number of experiments and reduce the cost of experimental research. A second-order non-position plan (Box-Bencken plan) was used, which reduced the number of trials from 81 to 27. The order of statistical data research of Box-Benken plan using standard tools of integrated system for analysis and data management STATISTICA Design of Experiments is considered. Results of statistical data processing with significance estimation of coefficients and adequacy of mathematical models are presented.

  11. Mathematical and numerical analysis of the resistive magnetohydrodynamics system with self-generated magnetic field terms

    International Nuclear Information System (INIS)

    Wolff, Marc

    2011-01-01

    This work is devoted to the construction of numerical methods that allow the accurate simulation of inertial confinement fusion (ICF) implosion processes by taking self-generated magnetic field terms into account. In the sequel, we first derive a two-temperature resistive magnetohydrodynamics model and describe the considered closure relations. The resulting system of equations is then split in several subsystems according to the nature of the underlying mathematical operator. Adequate numerical methods are then proposed for each of these subsystems. Particular attention is paid to the development of finite volume schemes for the hyperbolic operator which actually is the hydrodynamics or ideal magnetohydrodynamics system depending on whether magnetic fields are considered or not. More precisely, a new class of high-order accurate dimensionally split schemes for structured meshes is proposed using the Lagrange re-map formalism. One of these schemes' most innovative features is that they have been designed in order to take advantage of modern massively parallel computer architectures. This property can for example be illustrated by the dimensionally split approach or the use of artificial viscosity techniques and is practically highlighted by sequential performance and parallel efficiency figures. Hyperbolic schemes are then combined with finite volume methods for dealing with the thermal and resistive conduction operators and taking magnetic field generation into account. In order to study the characteristics and effects of self-generated magnetic field terms, simulation results are finally proposed with the complete two-temperature resistive magnetohydrodynamics model on a test problem that represents the state of an ICF capsule at the beginning of the deceleration phase. (author)

  12. AN ANALYSIS OF NUMBER SENSE AND MENTAL COMPUTATION IN THE LEARNING OF MATHEMATICS

    Directory of Open Access Journals (Sweden)

    Parmit Singh Aperapar

    2011-04-01

    Full Text Available The purpose of this research was to assess students’ understanding of number sense and mental computation among Form One, Form Two, Form Three and Form Four students. A total of 1756 students, ages ranging from 12 to 17 years, from thirteen schools in Selangor participated in this study. A majority (74.9% of these students obtained an A grade for their respective year-end school examinations. The design for this study was quantitative in nature where the data on student’s sense of numbers was collected using two instruments, namely, Number Sense Test and Mental Computation Test. Each of these instruments consisted of 50 and 45 items respectively. The results from this study indicate that students were not able to cope to the Number Sense Test as compared to the Mental Computation Test. The former unveils a low percentage of 37.3% to 47.7% as compared to the latter of 79% to 88.6% across the levels. In the number Sense Test, surprisingly, there was no significant difference in the results between Form 1 students and Form 2 students and also between Form 3 students and Form 4 students. This seems to indicate that as the number of years in schools increase, there is an increasing reliance on algorithm and procedures. Although in the literature it has been argued that including mental computation in a mathematics curriculum promotes number sense (McIntosh et. al., 1997; Reys, Reys, Nohda, & Emori, 2005, this was not the case in this study. It seems that an over reliance on paper and pencil computation at the expense of intuitive understanding of numbers is taking place among these students.

  13. Finite element historical deformation analysis in piecewise linear plasticity by mathematical programming

    International Nuclear Information System (INIS)

    De Donato, O.; Parisi, M.A.

    1977-01-01

    When loads increase proportionally beyond the elastic limit in the presence of elastic-plastic piecewise-linear constitutive laws, the problem of finding the whole evolution of the plastic strain and displacements of structures was recently shown to be amenable to a parametric linear complementary problem (PLCP) in which the parameter is represented by the load factor, the matrix is symmetric positive definite or at least semi-definite (for perfect plasticity) and the variables with a direct mechanical meaning are the plastic multipliers. With reference to plane trusses and frames with elastic-plastic linear work-hardening material behaviour numerical solutions were also fairly efficiently obtained using a recent mathematical programming algorithm (due to R.W. Cottle) which is able to provide the whole deformation history of the structure and, at the same time to rule out local unloadings along the given proportional loading process by means of 'a priori' checks carried out before each pivotal step of the procedure. Hence it becomes possible to use the holonomic (reversible, path-independent) constitutive laws in finite terms and to benefit by all the relevant numerical and computational advantages despite the non-holonomic nature of plastic behaviour. In the present paper the method of solution is re-examined in view to overcome an important drawback of the algorithm deriving from the size of PLCP fully populated matrix when structural problems with large number of variables are considered and, consequently, the updating, the storing or, generally, the handling of the current tableau may become prohibitive. (Auth.)

  14. Exploring mathematics anxiety and attitude: Mathematics students' experiences

    Science.gov (United States)

    Sahri, Nurul Ashikin; Kamaruzaman, Wan Nur Farahdalila Wan; Jamil, Jastini Mohd.; Shaharanee, Izwan Nizal Mohd.

    2017-11-01

    A quantitative and correlational, survey methods were used to investigate the relationships among mathematical anxiety and attitude toward student's mathematics performance. Participants were 100 students volunteer to enroll in undergraduate Industrial Statistics, Decision Sciences and Business Mathematics at one of northern university in Malaysia. Survey data consisted of demographic items and Likert scale items. The collected data was analyzed by using the idea of correlation and regression analysis. The results indicated that there was a significant positive relationship between students' attitude and mathematics anxiety. Results also indicated that a substantial positive effect of students' attitude and mathematics anxiety in students' achievement. Further study can be conducted on how mathematical anxiety and attitude toward mathematics affects can be used to predict the students' performance in the class.

  15. Engineering mathematics

    CERN Document Server

    Bird, John

    2014-01-01

    A practical introduction to the core mathematics required for engineering study and practiceNow in its seventh edition, Engineering Mathematics is an established textbook that has helped thousands of students to succeed in their exams.John Bird's approach is based on worked examples and interactive problems. This makes it ideal for students from a wide range of academic backgrounds as the student can work through the material at their own pace. Mathematical theories are explained in a straightforward manner, being supported by practical engineering examples and applications in order to ensure

  16. Mathematical physics

    CERN Document Server

    Geroch, Robert

    1985-01-01

    Mathematical Physics is an introduction to such basic mathematical structures as groups, vector spaces, topological spaces, measure spaces, and Hilbert space. Geroch uses category theory to emphasize both the interrelationships among different structures and the unity of mathematics. Perhaps the most valuable feature of the book is the illuminating intuitive discussion of the ""whys"" of proofs and of axioms and definitions. This book, based on Geroch's University of Chicago course, will be especially helpful to those working in theoretical physics, including such areas as relativity, particle

  17. Applied mathematics

    CERN Document Server

    Logan, J David

    2013-01-01

    Praise for the Third Edition"Future mathematicians, scientists, and engineers should find the book to be an excellent introductory text for coursework or self-study as well as worth its shelf space for reference." -MAA Reviews Applied Mathematics, Fourth Edition is a thoroughly updated and revised edition on the applications of modeling and analyzing natural, social, and technological processes. The book covers a wide range of key topics in mathematical methods and modeling and highlights the connections between mathematics and the applied and nat

  18. Speed mathematics

    CERN Document Server

    Handley, Bill

    2012-01-01

    This new, revised edition of the bestselling Speed Mathematics features new chapters on memorising numbers and general information, calculating statistics and compound interest, square roots, logarithms and easy trig calculations. Written so anyone can understand, this book teaches simple strategies that will enable readers to make lightning-quick calculations. People who excel at mathematics use better strategies than the rest of us; they are not necessarily more intelligent. With Speed Mathematics you'll discover methods to make maths easy and fun. This book is perfect for stud

  19. Summary of research in applied mathematics, numerical analysis, and computer sciences

    Science.gov (United States)

    1986-01-01

    The major categories of current ICASE research programs addressed include: numerical methods, with particular emphasis on the development and analysis of basic numerical algorithms; control and parameter identification problems, with emphasis on effective numerical methods; computational problems in engineering and physical sciences, particularly fluid dynamics, acoustics, and structural analysis; and computer systems and software, especially vector and parallel computers.

  20. Discrete mathematics using a computer

    CERN Document Server

    Hall, Cordelia

    2000-01-01

    Several areas of mathematics find application throughout computer science, and all students of computer science need a practical working understanding of them. These core subjects are centred on logic, sets, recursion, induction, relations and functions. The material is often called discrete mathematics, to distinguish it from the traditional topics of continuous mathematics such as integration and differential equations. The central theme of this book is the connection between computing and discrete mathematics. This connection is useful in both directions: • Mathematics is used in many branches of computer science, in applica­ tions including program specification, datastructures,design and analysis of algorithms, database systems, hardware design, reasoning about the correctness of implementations, and much more; • Computers can help to make the mathematics easier to learn and use, by making mathematical terms executable, making abstract concepts more concrete, and through the use of software tools su...