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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
491

O ensino de cálculo: dificuldades de natureza epistemológica / The teaching of calculus: difficulties of an epistemological nature

Rezende, Wanderley Moura 12 June 2003 (has links)
São notórias e bem evidentes as dificuldades de aprendizagem no ensino de Cálculo. Algumas tentativas de resolver, ou pelo menos, amenizar, este problema têm sido realizadas tanto no campo pedagógico quanto no âmbito da pesquisa. Muitas dessas ações, inseridas no próprio contexto do ensino superior de Cálculo, partem do pressuposto que essas dificuldades de aprendizagem são de natureza psicológica, internas ao sujeito aprendiz. No entanto, contrariando esta tendência, esta pesquisa pretende mostrar que parte significativa dos problemas de aprendizagem do atual ensino de Cálculo é de natureza essencialmente epistemológica, está além dos métodos e das técnicas de ensino, sendo inclusive anterior ao seu próprio tempo de realização. Diante disto, foram imaginadas duas ações inter-relacionadas, dois mapeamentos que visam ao levantamento e entendimento dessas dificuldades de natureza epistemológica no ensino de Cálculo: um mapeamento conceitual do Cálculo e de suas idéias e procedimentos básicos; em seguida, munido desses elementos, realizou-se efetivamente o mapeamento das dificuldades supracitadas. Assim, a partir do entrelaçamento dos fatos históricos e pedagógicos, e tendo como pano de fundo as dualidades essenciais e os mapas conceituais do Cálculo, foram explicitados e consubstanciados cinco macro-espaços de dificuldades de aprendizagem de natureza epistemológica, cinco eixos que estruturam o ensino de Cálculo, a saber: o eixo discreto/contínuo; o eixo variabilidade/permanência; o eixo finito/infinito; o eixo local/global; e o eixo sistematização/construção. Nesse esforço filosófico, foram estabelecidas relações entre os macro-espaços determinados com os mapas históricos e conceituais do Cálculo, e destes com o ensino de matemática em todos os níveis. Então, pôde-se perceber, em essência, um único lugar-matriz das dificuldades de aprendizagem de natureza epistemológica do ensino de Cálculo: o da omissão/evitação das idéias básicas e dos problemas construtores do Cálculo no ensino de Matemática em sentido amplo. Isto posto, para romper com o isolamento semântico, a subestimação da relevância das idéias e dos instrumentos característicos do Cálculo, propõem-se algumas intervenções didáticas relativas ao ensino básico de Matemática e ao ensino do próprio Cálculo. O que se pretende com isso é possibilitar ao Cálculo exercer no campo pedagógico a mesma função integradora que ele realizou no âmbito científico, no processo de construção do conhecimento matemático. / The difficulties in learning Calculus are noticeable and quite evident. Some attempts to solve, or at least, soften, this problem have been made both in the pedagogical field and in the scope of the research. Many of these actions, within the context of a higher teaching of Calculus itself, assume that such difficulties in learning are of a psychological nature, internal to the learner. However, contrary to this tendency, this research intends to show that a significant part of the problems of learning the current teaching of Calculus is of a nature essentially epistemological, it is beyond the methods and the techniques of teaching, being also prior to its own time of realization. With that in mind, there were imagined two actions interrelated, two mappings which aim the rising and understanding of these difficulties of an epistemological nature in the teaching of Calculus: a conceptual mapping of Calculus and of its ideas and basic procedures; next, having these instruments, the mapping of the previously mentioned difficulties was effectively done. Thus, from the interlacement of the historical and pedagogical facts, and having as background the essential dualities and the conceptual maps of Calculus, there were clarified and consubstantiated five macro spaces of the difficulties in learning of an epistemological nature, five axes which structure the teaching of Calculus, namely: the axis discreet/continuous; the axis variability/permanence; the axis finite/infinite; the axis local/global; and the axis systematization/construction. In this philosophical endeavour there were established relations between the macro spaces determined by the historical and conceptual maps of Calculus, and from these with the teaching of mathematics in all levels. Therefore, one can notice, essentially, a single point of origin in the difficulties in the learning of an epistemological nature in the teaching of Calculus: the omission/avoidance of the basic ideas and the construction problems of Calculus in the teaching of mathematics in an ample sense. So, to break up with the semantic isolation, the underestimation of the relevance of the ideas and of the instruments characteristics of Calculus, some didactic interventions are proposed in the field of the basic teaching of Mathematics and in the teaching of Calculus itself. What is expected from this is to allow Calculus to have in the pedagogical field the same function of integration that it had in the scientific field, in the process of building the mathematical knowledge.
492

Deterministic and Stochastic Bellman's Optimality Principles on Isolated Time Domains and Their Applications in Finance

Turhan, Nezihe 01 May 2011 (has links)
The concept of dynamic programming was originally used in late 1949, mostly during the 1950s, by Richard Bellman to describe decision making problems. By 1952, he refined this to the modern meaning, referring specifically to nesting smaller decision problems inside larger decisions. Also, the Bellman equation, one of the basic concepts in dynamic programming, is named after him. Dynamic programming has become an important argument which was used in various fields; such as, economics, finance, bioinformatics, aerospace, information theory, etc. Since Richard Bellman's invention of dynamic programming, economists and mathematicians have formulated and solved a huge variety of sequential decision making problems both in deterministic and stochastic cases; either finite or infinite time horizon. This thesis is comprised of five chapters where the major objective is to study both deterministic and stochastic dynamic programming models in finance. In the first chapter, we give a brief history of dynamic programming and we introduce the essentials of theory. Unlike economists, who have analyzed the dynamic programming on discrete, that is, periodic and continuous time domains, we claim that trading is not a reasonably periodic or continuous act. Therefore, it is more accurate to demonstrate the dynamic programming on non-periodic time domains. In the second chapter we introduce time scales calculus. Moreover, since it is more realistic to analyze a decision maker’s behavior without risk aversion, we give basics of Stochastic Calculus in this chapter. After we introduce the necessary background, in the third chapter we construct the deterministic dynamic sequence problem on isolated time scales. Then we derive the corresponding Bellman equation for the sequence problem. We analyze the relation between solutions of the sequence problem and the Bellman equation through the principle of optimality. We give an example of the deterministic model in finance with all details of calculations by using guessing method, and we prove uniqueness and existence of the solution by using the Contraction Mapping Theorem. In the fourth chapter, we define the stochastic dynamic sequence problem on isolated time scales. Then we derive the corresponding stochastic Bellman equation. As in the deterministic case, we give an example in finance with the distributions of solutions.
493

Stability of dual discretization methods for partial differential equations

Gillette, Andrew Kruse 06 July 2011 (has links)
This thesis studies the approximation of solutions to partial differential equations (PDEs) over domains discretized by the dual of a simplicial mesh. While `primal' methods associate degrees of freedom (DoFs) of the solution with specific geometrical entities of a simplicial mesh (simplex vertices, edges, faces, etc.), a `dual discretization method' associates DoFs with the geometric duals of these objects. In a tetrahedral mesh, for instance, a primal method might assign DoFs to edges of tetrahedra while a dual method for the same problem would assign DoFs to edges connecting circumcenters of adjacent tetrahedra. Dual discretization methods have been proposed for various specific PDE problems, especially in the context of electromagnetics, but have not been analyzed using the full toolkit of modern numerical analysis as is considered here. The recent and still-developing theories of finite element exterior calculus (FEEC) and discrete exterior calculus (DEC) are shown to be essential in understanding the feasibility of dual methods. These theories treat the solutions of continuous PDEs as differential forms which are then discretized as cochains (vectors of DoFs) over a mesh. While the language of DEC is ideal for describing dual methods in a straightforward fashion, the results of FEEC are required for proving convergence results. Our results about dual methods are focused on two types of stability associated with PDE solvers: discretization and numerical. Discretization stability analyzes the convergence of the approximate solution from the discrete method to the continuous solution of the PDE as the maximum size of a mesh element goes to zero. Numerical stability analyzes the potential roundoff errors accrued when computing an approximate solution. We show that dual methods can attain the same approximation power with regard to discretization stability as primal methods and may, in some circumstances, offer improved numerical stability properties. A lengthier exposition of the approach and a detailed description of our results is given in the first chapter of the thesis. / text
494

A Collaborative Model for Calculus Reform—A Preliminary Report

Liu, Po-Hung, Lin, Ching-Ching, Chen, Tung-Shyan, Chung, Yen-Tung, Liao, Chiu-Hsiung, Lin, Pi-Chuan, Tseng, Hwai-En, Chen, Ruey-Maw 04 May 2012 (has links) (PDF)
For the past two decades, both pros and cons of calculus reform have been discussed. A question often asked is, “Has the calculus reform project improved students’ understanding of mathematics?” The advocates of the reform movement claim that reform-based calculus may help students gain an intuitive understanding of mathematical propositions and have a better grasp of the real-world applications. Nonetheless, many still question its effect and argue that calculus reform purges calculus of its mathematical rigor and poorly prepares students for advanced mathematical training. East Asian students often rank in the top 10 of TIMSS and PISA. However, out-performing others in an international comparison may not guarantee their success in the learning of calculus. Taiwanese college students usually have a high failure rate in calculus. The National Science Council of Taiwan therefore initiated several projects in 2008 for improving students’ learning in calculus. This paper provides a preliminary report on one of the projects, PLEASE, and discusses how it was planned to respond to the tenets of calculus reform movement.
495

Teaching and learning introductory differential calculus with a computer algebra system

Kendal, Margaret Unknown Date (has links) (PDF)
Computer Algebra Systems (CAS), a powerful mathematical software currently available on hand held calculators, is becoming increasingly available to assist secondary students learn school mathematics. This study investigates how two teachers taught introductory differential calculus to their Year 11 classes using multiple representations in a CAS-supported curriculum. This thesis aims to explore the impact of the teaching on students’ understanding of the concept of derivative. / Understanding of the concept of derivative was gauged using an innovative Differentiation Competency Framework that was developed to describe understanding of the concept of derivative. It consists of eighteen competencies for formulation and interpretation of derivatives with, and without, translation between different representations. It clarified the objectives of the curriculum, purpose for using particular CAS activities, and also guided the construction of individual test items on the Differentiation Competency Test that enabled individual and class learning about the concept of derivative to be identified. / The Framework also helped identify each teacher’s privileging characteristics and facilitated analysis of the learning in relation to the teaching. / This study found that using multiple representations was important in developing understanding of the concept of derivative but that the graphical and the symbolic representations were the most useful and important to emphasize and link. / Analysis of the teaching actions showed that the teachers used CAS in ways that were consistent with their teaching approach and preferred use of representations and that a conceptual teaching method and student-centred style supported understanding of the concept of derivative. / Teaching is directly linked to learning and each class developed a different understanding of the concept of derivative that related to the combined effect of their teacher’s privileging characteristics: calculus content, teaching approach, and use of CAS. This study also shows that if a CAS-supported curriculum is to be successfully implemented, it needs to acquire institutional status including a corresponding change in assessment to legitimize new teaching practices.
496

Algumas aplicações de física do ensino médio a partir do cálculo diferencial e integral

Cruz, Lucas Cavalcanti 13 March 2013 (has links)
Submitted by Clebson Anjos (clebson.leandro54@gmail.com) on 2015-05-19T17:40:38Z No. of bitstreams: 1 arquivototal.pdf: 2323811 bytes, checksum: 20502fb243accb4b20bee61f4a53c331 (MD5) / Approved for entry into archive by Clebson Anjos (clebson.leandro54@gmail.com) on 2015-05-19T17:40:57Z (GMT) No. of bitstreams: 1 arquivototal.pdf: 2323811 bytes, checksum: 20502fb243accb4b20bee61f4a53c331 (MD5) / Made available in DSpace on 2015-05-19T17:40:57Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2323811 bytes, checksum: 20502fb243accb4b20bee61f4a53c331 (MD5) Previous issue date: 2013-03-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This paper deals with the teaching of topics in Di erential and Integral Calculus in high school. A brief historical analysis of its development, showing some ideas that served for its currently formalization. Some calculus' elements are also de ned to compare them with some intuitive notions or geometric ideas. To nalize it will discuss the importance and usefulness of these issues to other disciplines, particularly physics and how, from some applications, students could understand various concepts in a more simple way and does not require to memorize a huge amount of formulas. / Este trabalho trata do ensino de tópicos de Cálculo Diferencial e Integral no Ensino Médio. É feita uma breve análise histórica do seu desenvolvimento, mostrando algumas ideias que serviram para sua formalização conforme temos atualmente. São de nidos alguns elementos do cálculo para compará-los com algumas noções intuitivas ou ideias geométricas. Para nalizar, será discutida a importância e a utilidade desses assuntos para outras disciplinas, em particular a Física e como, a partir de algumas aplicações, os estudantes poderiam compreender vários conceitos de maneira mais simples e não necessitariam memorizar uma quantidade enorme de fórmulas.
497

O ensino de cálculo: dificuldades de natureza epistemológica / The teaching of calculus: difficulties of an epistemological nature

Wanderley Moura Rezende 12 June 2003 (has links)
São notórias e bem evidentes as dificuldades de aprendizagem no ensino de Cálculo. Algumas tentativas de resolver, ou pelo menos, amenizar, este problema têm sido realizadas tanto no campo pedagógico quanto no âmbito da pesquisa. Muitas dessas ações, inseridas no próprio contexto do ensino superior de Cálculo, partem do pressuposto que essas dificuldades de aprendizagem são de natureza psicológica, internas ao sujeito aprendiz. No entanto, contrariando esta tendência, esta pesquisa pretende mostrar que parte significativa dos problemas de aprendizagem do atual ensino de Cálculo é de natureza essencialmente epistemológica, está além dos métodos e das técnicas de ensino, sendo inclusive anterior ao seu próprio tempo de realização. Diante disto, foram imaginadas duas ações inter-relacionadas, dois mapeamentos que visam ao levantamento e entendimento dessas dificuldades de natureza epistemológica no ensino de Cálculo: um mapeamento conceitual do Cálculo e de suas idéias e procedimentos básicos; em seguida, munido desses elementos, realizou-se efetivamente o mapeamento das dificuldades supracitadas. Assim, a partir do entrelaçamento dos fatos históricos e pedagógicos, e tendo como pano de fundo as dualidades essenciais e os mapas conceituais do Cálculo, foram explicitados e consubstanciados cinco macro-espaços de dificuldades de aprendizagem de natureza epistemológica, cinco eixos que estruturam o ensino de Cálculo, a saber: o eixo discreto/contínuo; o eixo variabilidade/permanência; o eixo finito/infinito; o eixo local/global; e o eixo sistematização/construção. Nesse esforço filosófico, foram estabelecidas relações entre os macro-espaços determinados com os mapas históricos e conceituais do Cálculo, e destes com o ensino de matemática em todos os níveis. Então, pôde-se perceber, em essência, um único lugar-matriz das dificuldades de aprendizagem de natureza epistemológica do ensino de Cálculo: o da omissão/evitação das idéias básicas e dos problemas construtores do Cálculo no ensino de Matemática em sentido amplo. Isto posto, para romper com o isolamento semântico, a subestimação da relevância das idéias e dos instrumentos característicos do Cálculo, propõem-se algumas intervenções didáticas relativas ao ensino básico de Matemática e ao ensino do próprio Cálculo. O que se pretende com isso é possibilitar ao Cálculo exercer no campo pedagógico a mesma função integradora que ele realizou no âmbito científico, no processo de construção do conhecimento matemático. / The difficulties in learning Calculus are noticeable and quite evident. Some attempts to solve, or at least, soften, this problem have been made both in the pedagogical field and in the scope of the research. Many of these actions, within the context of a higher teaching of Calculus itself, assume that such difficulties in learning are of a psychological nature, internal to the learner. However, contrary to this tendency, this research intends to show that a significant part of the problems of learning the current teaching of Calculus is of a nature essentially epistemological, it is beyond the methods and the techniques of teaching, being also prior to its own time of realization. With that in mind, there were imagined two actions interrelated, two mappings which aim the rising and understanding of these difficulties of an epistemological nature in the teaching of Calculus: a conceptual mapping of Calculus and of its ideas and basic procedures; next, having these instruments, the mapping of the previously mentioned difficulties was effectively done. Thus, from the interlacement of the historical and pedagogical facts, and having as background the essential dualities and the conceptual maps of Calculus, there were clarified and consubstantiated five macro spaces of the difficulties in learning of an epistemological nature, five axes which structure the teaching of Calculus, namely: the axis discreet/continuous; the axis variability/permanence; the axis finite/infinite; the axis local/global; and the axis systematization/construction. In this philosophical endeavour there were established relations between the macro spaces determined by the historical and conceptual maps of Calculus, and from these with the teaching of mathematics in all levels. Therefore, one can notice, essentially, a single point of origin in the difficulties in the learning of an epistemological nature in the teaching of Calculus: the omission/avoidance of the basic ideas and the construction problems of Calculus in the teaching of mathematics in an ample sense. So, to break up with the semantic isolation, the underestimation of the relevance of the ideas and of the instruments characteristics of Calculus, some didactic interventions are proposed in the field of the basic teaching of Mathematics and in the teaching of Calculus itself. What is expected from this is to allow Calculus to have in the pedagogical field the same function of integration that it had in the scientific field, in the process of building the mathematical knowledge.
498

Elektronická učebnice matematických metod fyziky / Electronic Textbook in Mathematical Methods of Physics

Kolář, Petr January 2016 (has links)
Title: Electronic Textbook in Mathematical Methods of Physics Author: Bc. Petr Kolář Department: Department of Physics Education FMP CU Supervisor: RNDr. Vojtěch Žák, Ph.D., Department of Physics Education FMP CU Abstract: The objective of this work is to continue in Electronic Textbook in Introduction of Mathematical Methods of Physics and to create an other studing text not only for the first grade students (future physics teachers) at FMP CU but also for other students of physical and technical domains at universities which should help them with an introduction into mathematic necessary in physics. The main matter of this work is based on preparations and texts of dr. A Hladík, prof. J. Podolský and dr. V. Žák for lectures and exercises of subject Introduction of Mathematical Methods of Physics and Mathematical Methods in Physics I. The author's experience are also reflected. Equally, a small recherche of an existence and an availability of other sources pursuing given matters has been done. Some of these sources are recommended in this work. The created text should help readers with elementary matter of antiderivatives and Riemann integrals, double and triple integrals and integrals of the first kind with a special consideration to their applications in physics. A contribution of this and previous work for...
499

Approximations par champs de phases pour des problèmes de transport branché / Phase-field approximation for some branched transportation problems

Ferrari, Luca Alberto Davide 05 October 2018 (has links)
Dans cette thèse, nous concevons des approximations par champ de phase de certains problèmes de Transport Branché. Le Transport Branché est un cadre mathématique pour modéliser des réseaux de distribution offre-demande qui présentent une structure d'arbre. En particulier, le réseau, les usines d'approvisionnement et le lieu de la demande sont modélisés en tant que mesures et le probléme est présenté comme un probléme d'optimisation sous contrainte. Le coût de transport d'une masse m le long d'un bord de longueur L est h(m)xL et le coût total d'un réseau est défini comme la somme de la contribution sur tous ses arcs. Le cas du Transport Branché correspond avec la choix h(m) =|m|^α où α est dans [0,1). La sous-additivité de la fonction cout s'assure que déplacer deux masses conjointement est moins cher que de le faire séparément. Dans ce travail, nous introduisons diverses approximations variationnelles du problème du transport branché. Les fonctionnelles que on vais utiliser sont basées sur une représentation par champ de phase du réseau et sont plus lisses que le problème original, ce qui permet des méthodes d'optimisation numérique efficaces. Nous introduisons une famille des fonctionnelles inspirées par le fonctionnelle de Ambrosio et Tortorelli pour modéliser une fonction de coût h affine dans l'espace R^2. Pour ce cas, nous produisons un résultat complet de Gamma-convergence et nous le corrélons avec une procédure de minimisation alternée pour obtenir des approximations numériques des minimiseurs. Puis nous généralisons cette approche à n'importe quel espace R^n et obtenons un résultat complet de $Gamma$-convergence dans le cas de surfaces k-dimensionnelles avec k<n. En particulier, nous obtenons une approximation variationnelle du problème du Plateau dans n'importe quelle dimension et co-dimension. Dans la dernière partie de la thèse, nous proposons deux approches générales pour des fonctions de coût concave. Dans le premier, nous introduisons une approche par plusieurs champs de phase et récupérons n'importe quelle fonction de coût affine par morceaux. Enfin, nous proposons et étudions une famille de fonctions permettant d'obtenir dans la limite toutes fonction de coût concave h. / In this thesis we devise phase field approximations of some Branched Transportation problems. Branched Transportation is a mathematical framework for modeling supply-demand distribution networks which exhibit tree like structures. In particular the network, the supply factories and the demand location are modeled as measures and the problem is cast as a constrained optimization problem. The transport cost of a mass m along an edge with length L is h(m)xL and the total cost of a network is defined as the sum of the contribution on all its edges. The branched transportation case consists with the specific choice h(m)=|m|^α where α is a value in [0,1). The sub-additivity of the cost function ensures that transporting two masses jointly is cheaper than doing it separately. In this work we introduce various variational approximations of the branched transport optimization problem. The approximating functionals are based on a phase field representation of the network and are smoother than the original problem which allows for efficient numerical optimization methods. We introduce a family of functionals inspired by the Ambrosio and Tortorelli one to model an affine transport cost functions. This approach is firstly used to study the problem any affine cost function h in the ambient space R^2. For this case we produce a full Gamma-convergence result and correlate it with an alternate minimization procedure to obtain numerical approximations of the minimizers. We then generalize this approach to any ambient space and obtain a full Gamma-convergence result in the case of k-dimensional surfaces. In particular, we obtain a variational approximation of the Plateau problem in any dimension and co-dimension. In the last part of the thesis we propose two models for general concave cost functions. In the first one we introduce a multiphase field approach and recover any piecewise affine cost function. Finally we propose and study a family of functionals allowing to recover in the limit any concave cost function h.
500

The Perceptions of Alignment between Advanced Placement Calculus AB and College Calculus I: A Mixed Methods Study of Instructional Strategies, Curriculum, and Assessment.

Alexander, Anita Nicole 12 August 2019 (has links)
No description available.

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