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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.
141

Learning and Reasoning in Hybrid Structured Spaces

Morettin, Paolo 29 May 2020 (has links)
Many real world AI applications involve reasoning on both continuous and discrete variables, while requiring some level of symbolic reasoning that can provide guarantees on the system's behaviour. Unfortunately, most of the existing probabilistic models do not efficiently support hard constraints or they are limited to purely discrete or continuous scenarios. Weighted Model Integration (WMI) is a recent and general formalism that enables probabilistic modeling and inference in hybrid structured domains. A difference of WMI-based inference algorithms with respect to most alternatives is that probabilities are computed inside a structured support involving both logical and algebraic relationships between variables. While some progress has been made in the last years and the topic is increasingly gaining interest from the community, research in this area is at an early stage. These aspects motivate the study of hybrid and symbolic probabilistic models and the development of scalable inference procedures and effective learning algorithms in these domains. This PhD Thesis embodies my effort in studying scalable reasoning and learning techniques in the context of WMI.
142

Vybrané problémy účetnictví společnosti podnikající v oblasti internetového marketingu / Selected accounting problems of a company running its business in the area of internet marketing

Dvořák, Luboš January 2010 (has links)
The subject of the thesis is accounting problems that are specific to the area of internet marketing, and which usually do not occur in the accounting of companies in other business areas. These problems are especially connected with internet domains, the delivery of online customers and the delivery of web page traffic. For the issues described, possible solutions and illustrations of practical examples are offered.
143

The Collocation Trefftz Method for Laplace's Equation on Annular Shaped Domains, Circular and Elliptic Boundaries

Wu, Sin-Rong 19 August 2011 (has links)
The collocation Trefftz method (CTM) proposed in [36] is employed to annular shaped domains, and new error analysis is made to yield the optimal convergence rates. This popular method is then applied to the special case: the Dirichlet problems on circular domains with circular holes, and comparisons are made with the null field method (NFM) proposed , and new interior field method (IFM) proposed in [35], to find out that both errors and condition numbers are smaller. Recently, for circular domains with circular holes, the null fields method (NFM) is proposed by Chen and his groups. In NFM, the fundamental solutions (FS) with the source nodes Q outside of the solution domains are used in the Green formulas, and the FS are replaced by their series expansions. The Fourier expansions of the known or the unknown Dirichlet and Neumann boundary conditions on the circular boundaries are chosen, so that the explicit discrete equations can be easily obtained by means of orthogonality of Fourier functions. The NFM has been applied to elliptic equations and eigenvalue problems in circular domains with multiple holes, reported in many papers; here we cite those for Laplace¡¦s equation only (see [18, 19, 20]). For the boundary integral equation (BIE) of the first kind, the trigonometric functions are used in Arnold [4, 5], and error analysis is made for infinite smooth solutions, to derive the exponential convergence rates. In Cheng¡¦s Dissertation [21, 22], for BIE of the first kind, the source nodes are located outside of the solution domain, the linear combination of fundamental solutions are used, and error analysis is made only for circular domains. This fact implies that not only can the CTM be applied to arbitrary domains, but also a better numerical performance is provided. Since the algorithms of the CTM is simple and its programming is easy, the CTM is strongly recommended to replace the NFM for circular domains with circular holes in engineering problems.
144

On the Satisfiability of Temporal Logics with Concrete Domains

Carapelle, Claudia 08 December 2015 (has links) (PDF)
Temporal logics are a very popular family of logical languages, used to specify properties of abstracted systems. In the last few years, many extensions of temporal logics have been proposed, in order to address the need to express more than just abstract properties. In our work we study temporal logics extended by local constraints, which allow to express quantitative properties on data values from an arbitrary relational structure called the concrete domain. An example of concrete domain can be (Z, <, =), where the integers are considered as a relational structure over the binary order relation and the equality relation. Formulas of temporal logics with constraints are evaluated on data-words or data-trees, in which each node or position is labeled by a vector of data from the concrete domain. We call the constraints local because they can only compare values at a fixed distance inside such models. Several positive results regarding the satisfiability of LTL (linear temporal logic) with constraints over the integers have been established in the past years, while the corresponding results for branching time logics were only partial. In this work we prove that satisfiability of CTL* (computation tree logic) with constraints over the integers is decidable and also lift this result to ECTL*, a proper extension of CTL*. We also consider other classes of concrete domains, particularly ones that are \"tree-like\". We consider semi-linear orders, ordinal trees and trees of a fixed height, and prove decidability in this framework as well. At the same time we prove that our method cannot be applied in the case of the infinite binary tree or the infinitely branching infinite tree. We also look into extending the expressiveness of our logic adding non-local constraints, and find that this leads to undecidability of the satisfiability problem, even on very simple domains like (Z, <, =). We then find a way to restrict the power of the non-local constraints to regain decidability.
145

Unfolding Operators in Various Oscillatory Domains : Homogenization of Optimal Control Problems

Aiyappan, S January 2017 (has links) (PDF)
In this thesis, we study homogenization of optimal control problems in various oscillatory domains. Specifically, we consider four types of domains given in Figure 1 below. Figure 1: Oscillating Domains The thesis is organized into six chapters. Chapter 1 provides an introduction to our work and the rest of the thesis. The main contributions of the thesis are contained in Chapters 2-5. Chapter 6 presents the conclusions of the thesis and possible further directions. A brief description of our work (Chapters 2-5) follows: Chapter 2: Asymptotic behaviour of a fourth order boundary optimal control problem with Dirichlet boundary data posed on an oscillating domain as in Figure 1(A) is analyzed. We use the unfolding operator to study the asymptotic behavior of this problem. Chapter 3: Homogenization of a time dependent interior optimal control problem on a branched structure domain as in Figure 1(B) is studied. Here we pose control on the oscillating interior part of the domain. The analysis is carried out by appropriately defined unfolding operators suitable for this domain. The optimal control is characterized using various unfolding operators defined at each branch of every level. Chapter 4: A new unfolding operator is developed for a general oscillating domain as in Figure 1(C). Homogenization of a non-linear elliptic problem is studied using this new un-folding operator. Using this idea, homogenization of an optimal control problem on a circular oscillating domain as in Figure 1(D) is analyzed. Chapter 5: Homogenization of a non-linear optimal control problem posed on a smooth oscillating domain as in Figure 1(C) is studied using the unfolding operator.
146

Rigidity And Regularity Of Holomorphic Mappings

Balakumar, G P 07 1900 (has links) (PDF)
We deal with two themes that are illustrative of the rigidity and regularity of holomorphic mappings. The first one concerns the regularity of continuous CR mappings between smooth pseudo convex, finite type hypersurfaces which is a well studied subject for it is linked with the problem of studying the boundary behaviour of proper holomorphic mappings between domains bounded by such hypersurfaces. More specifically, we study the regularity of Lipschitz CR mappings from an h-extendible(or semi-regular) hypersurface in Cn .Under various assumptions on the target hypersurface, it is shown that such mappings must be smooth. A rigidity result for proper holomorphic mappings from strongly pseudo convex domains is also proved. The second theme dealt with, is the classification upto biholomorphic equivalence of model domains with abelian automorphism group in C3 .It is shown that every model domain i.e.,a hyperbolic rigid polynomial domainin C3 of finite type, with abelian automorphism group is equivalent to a domain that is balanced with respect to some weight.
147

Domínios intervalares da matemática computacional

Dimuro, Gracaliz Pereira January 1991 (has links)
Fundamentada a importância da utilização da Teoria dos Intervalos em computação científica, é realizada uma revisão da Teoria Clássica dos Intervalos, com críticas sobre as incompatibilidades encontradas como motivos de diversas dificuldades para desenvolvimento da própria teoria e, consequentemente, das Técnicas Intervalares. É desenvolvida uma nova abordagem para a Teoria dos Intervalos de acordo com a Teoria dos Domínios e a proposta de [ACI 89], obtendo-se os Domínios Intervalares da Matemática Computacional. Introduz-se uma topologia (Topologia de Scott) compatível com a idéia de aproximação, gerando uma ordem de informação, isto é, para quaisquer intervalos x e y, diz-se que se x -c y , então y fornece mais (no mínimo tanto quanto) informação, sobre um real r, do que x. Prova-se que esta ordem de informação induz uma topologia To (topologia de Scott) , que é mais adequada para uma teoria computacional que a topologia da Hausdorff introduzida por Moore [MOO 66]. Cada número real r é aproximado por intervalos de extremos racionais, os intervalos de informação, que constituem o espaço de informação II(Q), superando assim a regressão infinita da abordagem clássica. Pode-se dizer que todo real r é o supremo de uma cadeia de intervalos com extremos racionais “encaixados”. Assim, os reais são os elementos totais de um domínio contínuo, chamado de Domínio dos Intervalos Reais Parciais, cuja base é o espaço de informação II (Q). Cada função contínua da Análise Real é o limite de sequências de funções contínuas entre elementos da base do domínio. Toda função contínua nestes domínios constitui uma função monotônica na base e é completamente representada em termos finitos. É introduzida uma quasi-métrica que induz uma topologia compatível com esta abordagem e provê as propriedades quantitativas, além de possibilitar a utilização da noção de sequências, limites etc, sem que se precise recorrer a conceitos mais complexos. Desenvolvem-se uma aritmética, critérios de aproximação e os conceito de intervalo ponto médio, intervalo valor absoluto e intervalo diâmetro, conceitos compatíveis com esta abordagem. São acrescentadas as operações de união, interseção e as unárias. Apresenta-se um amplo estudo sobre a função intervalar e a inclusão de imagens de funções, com ênfase na obtenção de uma extensão intervalar natural contínua. Esta é uma abordagem de lógica construtiva e computacional. / The importance of Interval Theory for scientific computation is emphasized. A review of the Classical Theory is macle, including a discussion about some incompatibities that cause problems in developing interval algorithms. A new approach to the Interval Theory is developed in the light of the Theory of Domains and according to the ideas by Acióly [ACI 89], getting the Interval Domains of Computational Mathematics. It is introduced a topology (Scott Topology), which is associated with the idea of approximation, generating an information order, that is, for any intervals x and y one says that if x -c y, then "the information given by y is better or at least equal than the one given by x". One proves that this information order induces a To topology (Scott's topology) which is more suitable for a computation theory than that of Hausdorff introduced by Moore [MOO 66]. This approach has the advantage of being both of constructive logic and computational. Each real number is approximated by intervals with rational bounds, named information intervals of the Information Space II(Q), eliminating the infinite regression found in the classical approach. One can say that every real a is the supreme of a chain of rational intervals. Then, the real numbers are the total elements of a continuous domain, named the Domain of the Partial Real Intervals, whose basis is the information space II (Q). Each continuous function in the Real Analysis is the limit of sequences of continuous functions among any elements which belong to the base of the domain. In these same domains, each continuous function is monotonic on the base and it is completely represented by finite terms. It is introduced a quasi-metric that leads to a compatible topology and supplies the quantitative properties. An arithmetic, some approximation criteria, the concepts of mean point interval, absolute value interval and width interval are developed and set operations are added. The ideas of interval functions and the inclusion of ranges of functions are also presented, and a continuous natural interval extension is obtained.
148

Domínios intervalares da matemática computacional

Dimuro, Gracaliz Pereira January 1991 (has links)
Fundamentada a importância da utilização da Teoria dos Intervalos em computação científica, é realizada uma revisão da Teoria Clássica dos Intervalos, com críticas sobre as incompatibilidades encontradas como motivos de diversas dificuldades para desenvolvimento da própria teoria e, consequentemente, das Técnicas Intervalares. É desenvolvida uma nova abordagem para a Teoria dos Intervalos de acordo com a Teoria dos Domínios e a proposta de [ACI 89], obtendo-se os Domínios Intervalares da Matemática Computacional. Introduz-se uma topologia (Topologia de Scott) compatível com a idéia de aproximação, gerando uma ordem de informação, isto é, para quaisquer intervalos x e y, diz-se que se x -c y , então y fornece mais (no mínimo tanto quanto) informação, sobre um real r, do que x. Prova-se que esta ordem de informação induz uma topologia To (topologia de Scott) , que é mais adequada para uma teoria computacional que a topologia da Hausdorff introduzida por Moore [MOO 66]. Cada número real r é aproximado por intervalos de extremos racionais, os intervalos de informação, que constituem o espaço de informação II(Q), superando assim a regressão infinita da abordagem clássica. Pode-se dizer que todo real r é o supremo de uma cadeia de intervalos com extremos racionais “encaixados”. Assim, os reais são os elementos totais de um domínio contínuo, chamado de Domínio dos Intervalos Reais Parciais, cuja base é o espaço de informação II (Q). Cada função contínua da Análise Real é o limite de sequências de funções contínuas entre elementos da base do domínio. Toda função contínua nestes domínios constitui uma função monotônica na base e é completamente representada em termos finitos. É introduzida uma quasi-métrica que induz uma topologia compatível com esta abordagem e provê as propriedades quantitativas, além de possibilitar a utilização da noção de sequências, limites etc, sem que se precise recorrer a conceitos mais complexos. Desenvolvem-se uma aritmética, critérios de aproximação e os conceito de intervalo ponto médio, intervalo valor absoluto e intervalo diâmetro, conceitos compatíveis com esta abordagem. São acrescentadas as operações de união, interseção e as unárias. Apresenta-se um amplo estudo sobre a função intervalar e a inclusão de imagens de funções, com ênfase na obtenção de uma extensão intervalar natural contínua. Esta é uma abordagem de lógica construtiva e computacional. / The importance of Interval Theory for scientific computation is emphasized. A review of the Classical Theory is macle, including a discussion about some incompatibities that cause problems in developing interval algorithms. A new approach to the Interval Theory is developed in the light of the Theory of Domains and according to the ideas by Acióly [ACI 89], getting the Interval Domains of Computational Mathematics. It is introduced a topology (Scott Topology), which is associated with the idea of approximation, generating an information order, that is, for any intervals x and y one says that if x -c y, then "the information given by y is better or at least equal than the one given by x". One proves that this information order induces a To topology (Scott's topology) which is more suitable for a computation theory than that of Hausdorff introduced by Moore [MOO 66]. This approach has the advantage of being both of constructive logic and computational. Each real number is approximated by intervals with rational bounds, named information intervals of the Information Space II(Q), eliminating the infinite regression found in the classical approach. One can say that every real a is the supreme of a chain of rational intervals. Then, the real numbers are the total elements of a continuous domain, named the Domain of the Partial Real Intervals, whose basis is the information space II (Q). Each continuous function in the Real Analysis is the limit of sequences of continuous functions among any elements which belong to the base of the domain. In these same domains, each continuous function is monotonic on the base and it is completely represented by finite terms. It is introduced a quasi-metric that leads to a compatible topology and supplies the quantitative properties. An arithmetic, some approximation criteria, the concepts of mean point interval, absolute value interval and width interval are developed and set operations are added. The ideas of interval functions and the inclusion of ranges of functions are also presented, and a continuous natural interval extension is obtained.
149

Domínios intervalares da matemática computacional

Dimuro, Gracaliz Pereira January 1991 (has links)
Fundamentada a importância da utilização da Teoria dos Intervalos em computação científica, é realizada uma revisão da Teoria Clássica dos Intervalos, com críticas sobre as incompatibilidades encontradas como motivos de diversas dificuldades para desenvolvimento da própria teoria e, consequentemente, das Técnicas Intervalares. É desenvolvida uma nova abordagem para a Teoria dos Intervalos de acordo com a Teoria dos Domínios e a proposta de [ACI 89], obtendo-se os Domínios Intervalares da Matemática Computacional. Introduz-se uma topologia (Topologia de Scott) compatível com a idéia de aproximação, gerando uma ordem de informação, isto é, para quaisquer intervalos x e y, diz-se que se x -c y , então y fornece mais (no mínimo tanto quanto) informação, sobre um real r, do que x. Prova-se que esta ordem de informação induz uma topologia To (topologia de Scott) , que é mais adequada para uma teoria computacional que a topologia da Hausdorff introduzida por Moore [MOO 66]. Cada número real r é aproximado por intervalos de extremos racionais, os intervalos de informação, que constituem o espaço de informação II(Q), superando assim a regressão infinita da abordagem clássica. Pode-se dizer que todo real r é o supremo de uma cadeia de intervalos com extremos racionais “encaixados”. Assim, os reais são os elementos totais de um domínio contínuo, chamado de Domínio dos Intervalos Reais Parciais, cuja base é o espaço de informação II (Q). Cada função contínua da Análise Real é o limite de sequências de funções contínuas entre elementos da base do domínio. Toda função contínua nestes domínios constitui uma função monotônica na base e é completamente representada em termos finitos. É introduzida uma quasi-métrica que induz uma topologia compatível com esta abordagem e provê as propriedades quantitativas, além de possibilitar a utilização da noção de sequências, limites etc, sem que se precise recorrer a conceitos mais complexos. Desenvolvem-se uma aritmética, critérios de aproximação e os conceito de intervalo ponto médio, intervalo valor absoluto e intervalo diâmetro, conceitos compatíveis com esta abordagem. São acrescentadas as operações de união, interseção e as unárias. Apresenta-se um amplo estudo sobre a função intervalar e a inclusão de imagens de funções, com ênfase na obtenção de uma extensão intervalar natural contínua. Esta é uma abordagem de lógica construtiva e computacional. / The importance of Interval Theory for scientific computation is emphasized. A review of the Classical Theory is macle, including a discussion about some incompatibities that cause problems in developing interval algorithms. A new approach to the Interval Theory is developed in the light of the Theory of Domains and according to the ideas by Acióly [ACI 89], getting the Interval Domains of Computational Mathematics. It is introduced a topology (Scott Topology), which is associated with the idea of approximation, generating an information order, that is, for any intervals x and y one says that if x -c y, then "the information given by y is better or at least equal than the one given by x". One proves that this information order induces a To topology (Scott's topology) which is more suitable for a computation theory than that of Hausdorff introduced by Moore [MOO 66]. This approach has the advantage of being both of constructive logic and computational. Each real number is approximated by intervals with rational bounds, named information intervals of the Information Space II(Q), eliminating the infinite regression found in the classical approach. One can say that every real a is the supreme of a chain of rational intervals. Then, the real numbers are the total elements of a continuous domain, named the Domain of the Partial Real Intervals, whose basis is the information space II (Q). Each continuous function in the Real Analysis is the limit of sequences of continuous functions among any elements which belong to the base of the domain. In these same domains, each continuous function is monotonic on the base and it is completely represented by finite terms. It is introduced a quasi-metric that leads to a compatible topology and supplies the quantitative properties. An arithmetic, some approximation criteria, the concepts of mean point interval, absolute value interval and width interval are developed and set operations are added. The ideas of interval functions and the inclusion of ranges of functions are also presented, and a continuous natural interval extension is obtained.
150

Syllabification and Phrasing in Three Dialects of Sudanese Arabic

Abdel-Khalig, Ali 15 July 2014 (has links)
This study is a synchronic derivational analysis of phonological phenomena in three dialects of Sudanese Arabic. Its main goal is to provide a unified prosodic account of syncope and of the phonological processes functioning as strategies of repairing unsyllabified segments in the dialects of Urban Central Sudanese Arabic, Shukriiya, and Hamar. The domains of these processes are argued to follow from the degree of restriction that dialects place on word-level and phrase-level syllabification. To this end, the study proposes an analysis of syllabification in the three dialects that identifies the degree to which word-level syllabification is exhaustive, the segments that may be marked extrasyllabic and the conditions regulating their extrasyllabic status, the phrasal level at which these segments must be syllabified, and the level at which alteration to syllable structure is disallowed. In identifying the degrees of restriction dialects place on syllabification and resyllabification, the analysis provides a principled explanation for the levels of repair of unsyllabified segments as well as the domains of syncope. The study also provides an analysis of word stress and an analysis of phonological phrase formation. By revealing and accounting for the interesting phonological patterns attested in these dialects, the study aims to contribute to the area of Arabic phonology in general and to research on the typology of Arabic dialects in particular. In addition to the analyses proposed, its substantial contribution in this regard is a significant body of original data that is being analysed for the first time. With respect to dialects of Sudanese Arabic, the study represents a new direction of enquiry, one that seeks to disentangle their respective grammars and reveal the interesting ways in which they pattern alike and diverge.

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