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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.
151

Ensino-aprendizagem de análise combinatória através da resolução de problemas: um olhar para a sala de aula / Mathematics teaching and learning through problem solving and exploration: a reflective look in the classroom

Silva, Adeilson Pereira da 09 July 2013 (has links)
Made available in DSpace on 2015-09-25T12:21:29Z (GMT). No. of bitstreams: 1 PDF - Adeilson Pereira da Silva.pdf: 892569 bytes, checksum: 24fd05bf50e8a095031e7c4766214214 (MD5) Previous issue date: 2013-07-09 / This research seeks to outline a mapping of the Combinatorial Analysis teaching and learning, through practice in the classroom, using mathematics teaching and learning through problem solving and exploration, the result of a reflective look at our own practice as teacher-researcher. The research begins with an investigation in the field of Mathematics Education with the theme "Combinatorial Analysis teaching and learning". In developing this work, it was possible to observe the actual classroom practice reflected in the discussions and ideas relevant to the content of Combinatorial Analysis by the theoretical perspectives. Thus, the central ideas in the teaching and learning process in this matter were clarified and exposed the methodological perspectives in the use of mathematics teaching and learning through problem solving and exploration that content, when developed in real classrooms, not idealized. On the whole, bring a wander reflective on the subject of combinatorial analysis, problem solving, social constructivism, philosophy of mathematics and mathematics education, and educational research as a methodology with the school routine, making use of observations, records of the classes and materials used by students. In interventions, it was experienced various difficulties relevant to Combinatorial Analysis teaching and learning, as the distinction between arrangement and combination problems, which leads to the failure to perceive, to understand the problem, by the students, if the order the grouping of the elements is not relevant or in the count. The research provides contributions to the content of Combinatorial Analysis and a better understanding of the use of problem solving and exploration in the classroom, as a method of teaching and learning. In developing the survey, the routine requires the attention of the teacher as an essential element in making pedagogical. Then come taunts and reflections on the research with the everyday classroom, which imply a critical eye to it. This teaching practice entails an opportunity to change the status quo and the emancipation of students. It means therefore the search for a pedagogy that may be constituted as resistance to oppression in schools. / Essa pesquisa busca traçar um mapeamento do ensino-aprendizagem de Análise Combinatória, através da prática em sala de aula, utilizando como metodologia de ensino-aprendizagem a resolução e exploração de problemas, fruto de um olhar reflexivo para a nossa própria prática como professor-pesquisador. A pesquisa inicia com uma investigação no campo da Educação Matemática com o tema EnsinoAprendizagem de Análise Combinatória . No desenvolvimento do trabalho, foi possível observar a própria prática de sala de aula refletida nas discussões e nas ideias pertinentes ao conteúdo de Análise Combinatória apontadas pela literatura. Dessa forma, as ideias centrais no processo ensino-aprendizagem dessa matéria foram esclarecidas e expostas as perspectivas metodológicas no uso da exploração e resolução de problemas para o ensino-aprendizagem desse conteúdo, quando desenvolvido em salas de aula reais, não idealizadas. No todo, trazemos um caminhar reflexivo sobre o tema de análise combinatória, resolução de problemas, construtivismo social, filosofia da Matemática e Educação Matemática, tendo como metodologia a pesquisa pedagógica com o cotidiano escolar, fazendo uso de observações, registros das aulas e materiais utilizados pelos alunos. Na intervenção realizada, vivenciamos várias dificuldades pertinentes ao ensino-aprendizagem de Análise Combinatória, como a distinção entre problemas de Arranjo e de Combinação, o que acarreta o fato de não se perceber, na compreensão do problema, por parte dos alunos, se a ordem dos elementos no agrupamento é pertinente ou não na contagem. A pesquisa traz contribuições para o conteúdo de Análise Combinatória e para a melhor compreensão do uso da resolução de problemas em sala de aula, como metodologia de ensino-aprendizagem. No desenvolver da pesquisa, o cotidiano requer a atenção do professor como elemento indispensável ao fazer pedagógico. Surgem então provocações e reflexões quanto à pesquisa com o cotidiano da sala de aula, que implicam em um olhar crítico para a mesma. Essa prática docente enseja uma oportunidade de mudança do status quo e a emancipação dos estudantes. Significa, pois, a busca de uma pedagogia que venha se constituir como resistência à opressão sofrida nas escolas.
152

Aspectos combinatorios de identidades do tipo Rogers-Ramanujan / Aspects combinatorics of identities Rogers-Ramanujan type

Ribeiro, Andreia Cristina 24 November 2006 (has links)
Orientador: Jose Plinio de Oliveira Santos / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica / Made available in DSpace on 2018-08-07T19:25:43Z (GMT). No. of bitstreams: 1 Ribeiro_AndreiaCristina_D.pdf: 576297 bytes, checksum: 445154b7e26e801e909854c976d31c45 (MD5) Previous issue date: 2006 / Resumo: Neste trabalho são estudadas varias das identidades do tipo Rogers-Ramanujan dadas por Slater. Em 1985, Andrews, introduziram um método geral para se estender para duas variáveis identidades desse tipo de modo a se obter, como casos especiais, certas importantes funções de Ramanujan. Santos, em 1991, forneceu conjecturas para varias das famílias de polinômios que surgem nestas extensões tendo provado algumas delas. Sills, em sua tese de doutorado, em 2002, implementou procedimentos que permitem a demonstra¸c¿ao das conjecturas dadas por Santos. No presente trabalho, de forma diferente daquela dada por Andrews, s¿ao introduzidos parâmetros nas somas que aparecem nestas identidades, de modo a se obter, em cada caso, funções geradoras que fornecem interpretações combinatórias para partições onde ¿números¿s¿ao vistos como ¿vetores¿e que fornecem, para especiais valores dos parâmetros, interpretações novas para muitas das identidades de Slater / Abstract: In this work many of the identities of the Rogers-Ramanujan type given by Slater are considered. In 1985, Andrews, introduced a general method in other to extend to two variables identities of this type in order to get, as special cases, some important functions of Ramanujan. Santos, in 1991, gave conjectures for many of the family of polynomials that appears in those extensions providing the proofs for some of them. Sills, in his Ph.D. thesis in 2002 ,has implemented procedures allowing the proofs of the conjectures given by Santos. In the present work, in a form different from the one given by Andrews, parameters are introduced in the sums of the identities in such a way to get, in each case, generating functions giving combinatorial interpretations for partitions where ¿numbers¿are represented as ¿vectors¿and that can give, as special cases, combinatorial interpretations for many of the identities given by Slater / Doutorado / Matematica Aplicada / Doutor em Matemática Aplicada
153

Sobre o crivo de Eratóstenes-Legendre / About the Eratosthenes-Legendre sieve

Nascimento, Marcus Vinicius Silva, 1980- 04 September 2015 (has links)
Orientador: José Plínio de Oliveira Santos / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica / Made available in DSpace on 2018-08-27T11:40:03Z (GMT). No. of bitstreams: 1 Nascimento_MarcusViniciusSilva_M.pdf: 918557 bytes, checksum: de0f1627892732c764e7f5046966336f (MD5) Previous issue date: 2015 / Resumo: Nosso objetivo, nesse trabalho, é o de fazer um estudo sobre o método do crivo. A motivação reside no desejo de aplicar essas ideias a uma situação particular. Dividimos nosso trabalho em três partes. Na primeira fornecemos apenas as definições e con- ceitos básicos. Na segunda apresentamos o principio da inclusão-exclusão que embora sendo algo bastante conhecido merece destaque especial dada a sua importância como ferramenta no nosso trabalho. Na terceira e última parte, fazemos uma contextualização histórica e uma descrição da evolução das ideias do crivo de Eratóstenes-Legendre. A escolha desse crivo, dentre tantos outros, foi feita tendo em vista dois pontos. O primeiro é que o crivo de Eratóstenes-Legendre é o mais simples dentre os crivos estudados na teoria dos crivos. O segundo ponto está relacionado com o fato deste crivo fornecer a ideia geral dos crivos combinatoriais, uma vez que os crivos mais sofisticados são extensões de suas ideias básicas / Abstract: Our aim in this work is to make a study about the sieve method. The motivation lies in the intent of applying this idea in a particular situation. We splitted the study into three parts. The first part deals with definitions and basic concepts. In the second we present the principle of inclusion-exclusion while being something well known deserves special mention given its importance as a tool in our work. In the third and final part, we make a historical contextualization and a description of the evolution of the sieve Eratosthenes- Legendre ideas. The choice of sieve, among many others, has been made taking into account two points. The first is that the Eratosthenes-Legendre sieve is the simplest among the sieves studied the theory of sieves. The second point is related to the fact that this sieve provide the general idea of combinatorial sieve, since the more sophisticated sieves are extensions of its basic idea / Mestrado / Matematica Aplicada / Mestre em Matemática Aplicada
154

q- Enumeration of permutations avoiding adjacent patterns

Takalani, Ntendeni Annah 09 1900 (has links)
MSc (Mathematics) / Department of Mathematics and Applied Mathematics / See the attached abstract below
155

Classification and enumeration of finite semigroups

Distler, Andreas January 2010 (has links)
The classification of finite semigroups is difficult even for small orders because of their large number. Most finite semigroups are nilpotent of nilpotency rank 3. Formulae for their number up to isomorphism, and up to isomorphism and anti-isomorphism of any order are the main results in the theoretical part of this thesis. Further studies concern the classification of nilpotent semigroups by rank, leading to a full classification for large ranks. In the computational part, a method to find and enumerate multiplication tables of semigroups and subclasses is presented. The approach combines the advantages of computer algebra and constraint satisfaction, to allow for an efficient and fast search. The problem of avoiding isomorphic and anti-isomorphic semigroups is dealt with by supporting standard methods from constraint satisfaction with structural knowledge about the semigroups under consideration. The approach is adapted to various problems, and realised using the computer algebra system GAP and the constraint solver Minion. New results include the numbers of semigroups of order 9, and of monoids and bands of order 10. Up to isomorphism and anti-isomorphism there are 52,989,400,714,478 semigroups with 9 elements, 52,991,253,973,742 monoids with 10 elements, and 7,033,090 bands with 10 elements. That constraint satisfaction can also be utilised for the analysis of algebraic objects is demonstrated by determining the automorphism groups of all semigroups with 9 elements. A classification of the semigroups of orders 1 to 8 is made available as a data library in form of the GAP package Smallsemi. Beyond the semigroups themselves a large amount of precomputed properties is contained in the library. The package as well as the code used to obtain the enumeration results are available on the attached DVD.
156

On algorithm selection, with an application to combinatorial search problems

Kotthoff, Lars January 2012 (has links)
The Algorithm Selection Problem is to select the most appropriate way for solving a problem given a choice of different ways. Some of the most prominent and successful applications come from Artificial Intelligence and in particular combinatorial search problems. Machine Learning has established itself as the de facto way of tackling the Algorithm Selection Problem. Yet even after a decade of intensive research, there are no established guidelines as to what kind of Machine Learning to use and how. This dissertation presents an overview of the field of Algorithm Selection and associated research and highlights the fundamental questions left open and problems facing practitioners. In a series of case studies, it underlines the difficulty of doing Algorithm Selection in practice and tackles issues related to this. The case studies apply Algorithm Selection techniques to new problem domains and show how to achieve significant performance improvements. Lazy learning in constraint solving and the implementation of the alldifferent constraint are the areas in which we improve on the performance of current state of the art systems. The case studies furthermore provide empirical evidence for the effectiveness of using the misclassification penalty as an input to Machine Learning. After having established the difficulty, we present an effective technique for reducing it. Machine Learning ensembles are a way of reducing the background knowledge and experimentation required from the researcher while increasing the robustness of the system. Ensembles do not only decrease the difficulty, but can also increase the performance of Algorithm Selection systems. They are used to much the same ends in Machine Learning itself. We finally tackle one of the great remaining challenges of Algorithm Selection -- which Machine Learning technique to use in practice. Through a large-scale empirical evaluation on diverse data taken from Algorithm Selection applications in the literature, we establish recommendations for Machine Learning algorithms that are likely to perform well in Algorithm Selection for combinatorial search problems. The recommendations are based on strong empirical evidence and additional statistical simulations. The research presented in this dissertation significantly reduces the knowledge threshold for researchers who want to perform Algorithm Selection in practice. It makes major contributions to the field of Algorithm Selection by investigating fundamental issues that have been largely ignored by the research community so far.
157

Distinguishability of Public Keys and Experimental Validation: The McEliece Public-Keyed Cryptosystem

Unknown Date (has links)
As quantum computers continue to develop, they pose a threat to cryptography since many popular cryptosystems will be rendered vulnerable. This is because the security of most currently used asymmetric systems requires the computational hardness of the integer factorization problem, the discrete logarithm or the elliptic curve discrete logarithm problem. However, there are still some cryptosystems that resist quantum computing. We will look at code-based cryptography in general and the McEliece cryptosystem specifically. Our goal is to understand the structure behind the McEliece scheme, including the encryption and decryption processes, and what some advantages and disadvantages are that the system has to offer. In addition, using the results from Courtois, Finiasz, and Sendrier's paper in 2001, we will discuss a digital signature scheme based on the McEliece cryptosystem. We analyze one classical algebraic attack against the security analysis of the system based on the distinguishing problem whether the public key of the McEliece scheme is generated from a generating matrix of a binary Goppa code or a random binary matrix. The idea of the attack involves solving an algebraic system of equations and we examine the dimension of the solution space of the linearized system of equations. With the assistance from a paper in 2010 by Faugere, Gauthier-Umana, Otmani, Perret, Tillich, we will see the parameters needed for the intractability of the distinguishing problem. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
158

Generalized pattern matching applied to genetic analysis. / 通用性模式匹配在基因序列分析中的應用 / CUHK electronic theses & dissertations collection / Digital dissertation consortium / Tong yong xing mo shi pi pei zai ji yin xu lie fen xi zhong de ying yong

January 2011 (has links)
Approximate pattern matching problem is, given a reference sequence T, a pattern (query) Q, and a maximum allowed error e, to find all the substrings in the reference, such that the edit distance between the substrings and the pattern is smaller than or equal to the maximum allowed error. Though it is a well-studied problem in Computer Science, it gains a resurrection in Bioinformatics in recent years, largely due to the emergence of the next-generation high-throughput sequencing technologies. This thesis contributes in a novel generalized pattern matching framework, and applies it to solve pattern matching problems in general and alternative splicing detection (AS) in particular. AS is to map a large amount of next-generation sequencing short reads data to a reference human genome, which is the first and an important step in analyzing the sequenced data for further Biological analysis. The four parts of my research are as follows. / In the first part of my research work, we propose a novel deterministic pattern matching algorithm which applies Agrep, a well-known bit-parallel matching algorithm, to a truncated suffix array. Due to the linear cost of Agrep, the cost of our approach is linear to the number of characters processed in the truncated suffix array. We analyze the matching cost theoretically, and .obtain empirical costs from experiments. We carry out experiments using both synthetic and real DNA sequence data (queries) and search them in Chromosome-X of a reference human genome. The experimental results show that our approach achieves a speed-up of several magnitudes over standard Agrep algorithm. / In the fourth part, we focus on the seeding strategies for alternative splicing detection. We review the history of seeding-and-extending (SAE), and assess both theoretically and empirically the seeding strategies adopted in existing splicing detection tools, including Bowtie's heuristic and ABMapper's exact seedings, against the novel complementary quad-seeding strategy we proposed and the corresponding novel splice detection tool called CS4splice, which can handle inexact seeding (with errors) and all 3 types of errors including mismatch (substitution), insertion, and deletion. We carry out experiments using short reads (queries) of length 105bp comprised of several data sets consisting of various levels of errors, and align them back to a reference human genome (hg18). On average, CS4splice can align 88. 44% (recall rate) of 427,786 short reads perfectly back to the reference; while the other existing tools achieve much smaller recall rates: SpliceMap 48.72%, MapSplice 58.41%, and ABMapper 51.39%. The accuracies of CS4splice are also the highest or very close to the highest in all the experiments carried out. But due to the complementary quad-seeding that CS4splice use, it takes more computational resources, about twice (or more) of the other alternative splicing detection tools, which we think is practicable and worthy. / In the second part, we define a novel generalized pattern (query) and a framework of generalized pattern matching, for which we propose a heuristic matching algorithm. Simply speaking, a generalized pattern is Q 1G1Q2 ... Qc--1Gc--1 Qc, which consists of several substrings Q i and gaps Gi occurring in-between two substrings. The prototypes of the generalized pattern come from several real Biological problems that can all be modeled as generalized pattern matching problems. Based on a well-known seeding-and-extending heuristic, we propose a dual-seeding strategy, with which we solve the matching problem effectively and efficiently. We also develop a specialized matching tool called Gpattern-match. We carry out experiments using 10,000 generalized patterns and search them in a reference human genome (hg18). Over 98.74% of them can be recovered from the reference. It takes 1--2 seconds on average to recover a pattern, and memory peak goes to a little bit more than 1G. / In the third part, a natural extension of the second part, we model a real biological problem, alternative splicing detection, into a generalized pattern matching problem, and solve it using a proposed bi-directional seeding-and-extending algorithm. Different from all the other tools which depend on third-party tools, our mapping tool, ABMapper, is not only stand-alone but performs unbiased alignments. We carry out experiments using 427,786 real next-generation sequencing short reads data (queries) and align them back to a reference human genome (hg18). ABMapper achieves 98.92% accuracy and 98.17% recall rate, and is much better than the other state-of-the-art tools: SpliceMap achieves 94.28% accuracy and 78.13% recall rate;while TopHat 88.99% accuracy and 76.33% recall rate. When the seed length is set to 12 in ABMapper, the whole searching and alignment process takes about 20 minutes, and memory peak goes to a little bit more than 2G. / Ni, Bing. / Adviser: Kwong-Sak Leung. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical referencesTexture mapping (leaves 151-161). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
159

Utilizando técnicas de contagem no ensino fundamental

Fernandes, Marcelo Melo January 2014 (has links)
Orientador: Prof. Dr. André Ricardo Oliveira da Fonseca / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Mestrado Profissional em Matemática em Rede Nacional - PROFMAT, 2014. / Contar elementos pode ser uma das mais antigas atividades que o ser humano tem registro. O desenvolvimento desse assunto deu origem à análise combinatória que estuda técnicas de contagem sem a necessidade de contar os elementos um a um. O objetivo deste trabalho é desenvolver algumas técnicas de contagem durante o Ensino Fundamental, para que o aluno se aproprie delas, mesmo que intuitivamente, e diminua as dificuldades na formalização do conteúdo que ocorre apenas no Ensino Médio. Abordado pela maioria dos livros didáticos em pilares, como arranjos, permutações e combinações, muitas vezes induzem os estudantes à memorização de fórmulas, que podem ser objeto de uma simples escolha que julguem ser a mais adequada na resolução de determinado problema. / Counting elements can be one of the oldest activities that humans have recorded. This subject development gave rise to the combinatorial analysis studies which focus on counting techniques without the need to count the elements one by one. The aim of this work is to develop some techniques of counting during the Fundamental Education, for the student to take ownership of them, even intuitively, and decrease the difficulties when formalizing the content itself, what may occur only in High School. Approached by most textbooks on pillars, as arrangements, permutations and combinations, books often induce students to memorize formulas, which can be subject to a simple choice they deem to be most appropriate in solving a given problem.
160

Markov chains at the interface of combinatorics, computing, and statistical physics

Streib, Amanda Pascoe 22 March 2012 (has links)
The fields of statistical physics, discrete probability, combinatorics, and theoretical computer science have converged around efforts to understand random structures and algorithms. Recent activity in the interface of these fields has enabled tremendous breakthroughs in each domain and has supplied a new set of techniques for researchers approaching related problems. This thesis makes progress on several problems in this interface whose solutions all build on insights from multiple disciplinary perspectives. First, we consider a dynamic growth process arising in the context of DNA-based self-assembly. The assembly process can be modeled as a simple Markov chain. We prove that the chain is rapidly mixing for large enough bias in regions of Z^d. The proof uses a geometric distance function and a variant of path coupling in order to handle distances that can be exponentially large. We also provide the first results in the case of fluctuating bias, where the bias can vary depending on the location of the tile, which arises in the nanotechnology application. Moreover, we use intuition from statistical physics to construct a choice of the biases for which the Markov chain M_mon requires exponential time to converge. Second, we consider a related problem regarding the convergence rate of biased permutations that arises in the context of self-organizing lists. The Markov chain M_nn in this case is a nearest-neighbor chain that allows adjacent transpositions, and the rate of these exchanges is governed by various input parameters. It was conjectured that the chain is always rapidly mixing when the inversion probabilities are positively biased, i.e., we put nearest neighbor pair x<y in order with bias 1/2 <= p_{xy} <= 1 and out of order with bias 1-p_{xy}. The Markov chain M_mon was known to have connections to a simplified version of this biased card-shuffling. We provide new connections between M_nn and M_mon by using simple combinatorial bijections, and we prove that M_nn is always rapidly mixing for two general classes of positively biased {p_{xy}}. More significantly, we also prove that the general conjecture is false by exhibiting values for the p_{xy}, with 1/2 <= p_{xy} <= 1 for all x< y, but for which the transposition chain will require exponential time to converge. Finally, we consider a model of colloids, which are binary mixtures of molecules with one type of molecule suspended in another. It is believed that at low density typical configurations will be well-mixed throughout, while at high density they will separate into clusters. This clustering has proved elusive to verify, since all local sampling algorithms are known to be inefficient at high density, and in fact a new nonlocal algorithm was recently shown to require exponential time in some cases. We characterize the high and low density phases for a general family of discrete {it interfering binary mixtures} by showing that they exhibit a "clustering property' at high density and not at low density. The clustering property states that there will be a region that has very high area, very small perimeter, and high density of one type of molecule. Special cases of interfering binary mixtures include the Ising model at fixed magnetization and independent sets.

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