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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.
101

Operações espaciais robustas à imprecisão nas coordenadas geográficas / Spatial operations robusts to geographic coordinate imprecision

Oliveira, Welder Batista de 21 August 2017 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2017-10-05T20:06:57Z No. of bitstreams: 2 Dissertacao- Welder Batista de Oliveira - 2017.pdf: 2420889 bytes, checksum: c26aee2605e42f2a9aecb9ec2523464f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-10-06T11:09:11Z (GMT) No. of bitstreams: 2 Dissertacao- Welder Batista de Oliveira - 2017.pdf: 2420889 bytes, checksum: c26aee2605e42f2a9aecb9ec2523464f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-10-06T11:09:11Z (GMT). No. of bitstreams: 2 Dissertacao- Welder Batista de Oliveira - 2017.pdf: 2420889 bytes, checksum: c26aee2605e42f2a9aecb9ec2523464f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-21 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Geographic Information Systems have revolutionized geographic research over the past three decades. These systems commonly provide a number of features for processing andanalyzing spatial data, such as spatial join and skyline. Although relevant, the effectiveness of such functionalities is affected by the imprecision of the geographic coordinates obtained by the georeferencing method employed. Moreover, the error contained in the coordinates may present several distributional patterns, which demands the development of solutions that are generalist concerning the error pattern that they can handle properly. Finally, spatial operations are already computationally expensive in their deterministic version, which is aggravated by the introduction of the stochastic component. The pre-sent work presents a general structure of spatial operations solutions robust to imprecise coordinates based on the use of simulations and probabilistic adaptations of heuristics in the literature. In addition, to deal with the problems mentioned, the proposed structure is designed to contemplate the requirements of generality, accuracy and efficiency at levels that enable its practical application. The overall solution structure is composed of the combination of probabilistic versions of heuristics of the deterministic versions of the spatial operations and by Monte Carlo simulations. From that structure, specific solutions - as case studies - are developed for the spatial join and skyline. Theoretical and experimental results demonstrated the potential of the developed solutions to meet the threerequirements established in this work. / Os Sistemas de Informação Geográfica revolucionaram a pesquisa geográfica nas últimas três décadas. Esses sistemas comumente disponibilizam uma série de funcionalidades para processar e analisar dados espaciais, como, por exemplo, a junção espacial e a consulta skyline. Embora relevantes, a eficácia dessas funcionalidades é impactada pela imprecisão das coordenadas geográficas obtidas pelo método de georreferenciamento empregado. Além disso, o erro contido nas coordenadas pode apresentar diversos padrões distribucionais, o que demanda o desenvolvimento de soluções que sejam generalistas quanto ao padrão de erro que conseguem tratar adequadamente. Por fim, operações espaciais já são computacionalmente caras em sua versão determinística, o que se agrava com a introdução do componente estocástico. O presente trabalho apresenta uma estrutura geral para o desenvolvimento de soluções para operações espaciais robustas a coordenadas imprecisas. Além disso, para lidar com os problemas mencionados, a estrutura proposta é projetada para contemplar os requisitos de generalidade, eficácia e eficiência em patamares que viabilizem sua aplicação prática. A estrutura geral de solução é composta pela combinação de versões probabilísticas de heurísticas das versões determinísticas das operações espaciais e por simulações de Monte Carlo. A partir dela, são desenvolvidas as soluções específicas – como estudo de caso - para a skyline espacial e da junção espacial. Resultados teóricos e experimentais demonstraram o potencial das soluções desenvolvidas em atender aos três requisitos estabelecidos nesse trabalho.
102

Efficient processing of multiway spatial join queries in distributed systems / Processamento eficiente de consultas de multi-junção espacial em sistemas distribuídos

Oliveira, Thiago Borges de 29 November 2017 (has links)
Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2017-12-12T16:13:05Z No. of bitstreams: 2 Tese - Thiago Borges de Oliveira - 2017.pdf: 1684209 bytes, checksum: f64b32084ca6b13a58109e4d2cffe541 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-12-13T09:33:57Z (GMT) No. of bitstreams: 2 Tese - Thiago Borges de Oliveira - 2017.pdf: 1684209 bytes, checksum: f64b32084ca6b13a58109e4d2cffe541 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-12-13T09:33:57Z (GMT). No. of bitstreams: 2 Tese - Thiago Borges de Oliveira - 2017.pdf: 1684209 bytes, checksum: f64b32084ca6b13a58109e4d2cffe541 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-11-29 / Multiway spatial join is an important type of query in spatial data processing, and its efficient execution is a requirement to move spatial data analysis to scalable platforms as has already happened with relational and unstructured data. In this thesis, we provide a set of comprehensive models and methods to efficiently execute multiway spatial join queries in distributed systems. We introduce a cost-based optimizer that is able to select a good execution plan for processing such queries in distributed systems taking into account: the partitioning of data based on the spatial attributes of datasets; the intra-operator level of parallelism, which enables high scalability; and the economy of cluster resources by appropriately scheduling the queries before execution. We propose a cost model based on relevant metadata about the spatial datasets and the data distribution, which identifies the pattern of costs incurred when processing a query in this environment. We formalized the distributed multiway spatial join plan scheduling problem as a bi-objective linear integer model, considering the minimization of both the makespan and the communication cost as objectives. Three methods are proposed to compute schedules based on this model that significantly reduce the resource consumption required to process a query. Although targeting multiway spatial join query scheduling, these methods can be applied to other kinds of problems in distributed systems, notably problems that require both the alignment of data partitions and the assignment of jobs to machines. Additionally, we propose a method to control the usage of resources and increase system throughput in the presence of constraints on the network or processing capacity. The proposed cost-based optimizer was able to select good execution plans for all queries in our experiments, using public datasets with a significant range of sizes and complex spatial objects. We also present an execution engine that is capable of performing the queries with near-linear scalability with respect to execution time. / A multi-junção espacial é um tipo importante de consulta usada no processamento de dados espaciais e sua execução eficiente é um requisito para mover a análise de dados espaciais para plataformas escaláveis, assim como aconteceu com dados relacionais e não estruturados. Nesta tese, propomos um conjunto de modelos e métodos para executar eficientemente consultas de multi-junção espacial em sistemas distribuídos. Apresentamos um otimizador baseado em custos que seleciona um bom plano de execução levando em consideração: o particionamento de dados com base nos atributos espaciais dos datasets; o nível de paralelismo intra-operador que proporciona alta escalabilidade; e o escalonamento das consultas antes da execução que resulta em economia de recursos computacionais. Propomos um modelo de custo baseado em metadados dos datasets e da distribuição de dados, que identifica o padrão de custos incorridos no processamento de uma consulta neste ambiente. Formalizamos o problema de escalonamento de planos de execução da multi-junção espacial distribuída como um modelo linear inteiro bi-objetivo, que minimiza tanto o custo de processamento quanto o custo de comunicação. Propomos três métodos para gerar escalonamentos a partir deste modelo, os quais reduzem significativamente o consumo de recursos no processamento das consultas. Embora projetados para o escalonamento da multi-junção espacial, esses métodos podem também ser aplicados a outros tipos de problemas em sistemas distribuídos, que necessitam do alinhamento de partições de dados e da distribuição de tarefas a máquinas de forma balanceada. Além disso, propomos um método para controlar o uso de recursos e aumentar a vazão do sistema na presença de restrições nas capacidades da rede ou de processamento. O otimizador proposto foi capaz de selecionar bons planos de execução para todas as consultas em nossos experimentos, as quais usaram datasets públicos com uma variedade significativa de tamanhos e de objetos espaciais complexos. Apresentamos também uma máquina de execução, capaz de executar as consultas com escalabilidade próxima de linear em relação ao tempo de execução.
103

Conception physique statique et dynamique des entrepôts de données / Static and Dynamic Data Warehouses Design

Bouchakri, Rima 17 September 2015 (has links)
Les entrepôts de données permettent le stockage et la consolidation, en une seule localité, d'une quantité gigantesque d'information pour être interrogée par des requêtes décisionnelles complexes dites requêtes de jointures en étoiles. Afin d'optimiser ses requêtes, plusieurs travaux emploient des techniques d'optimisations comme les index de jointure binaires et la fragmentation horizontale durant la phase de conception physique d'un entrepôt de données. Cependant, ces travaux proposent des algorithmes statiques qui sélectionnent ces techniques de manière isolée et s'intéressent à l'optimisation d'un seul objectif à savoir les performances des requêtes. Notre principale contribution dans cette thèse est de proposer une nouvelle vision de sélection des techniques d'optimisation. Notre première contribution est une sélection incrémentale qui permet de mettre à jour de manière continuelle le schéma d'optimisation implémenté sur l'ED, ce qui assure l'optimisation continuelle des requêtes décisionnelles. Notre seconde contribution est une sélection incrémentale jointe qui combine deux techniques d'optimisation pour couvrir l'optimisation d'un maximum de requêtes et respecter au mieux les contraintes d'optimisation liées à chacune de ces techniques. A l'issu de ces propositions, nous avons constaté que la sélection incrémentale engendre un coût de maintenance de l'ED. Ainsi, notre troisième proposition est une formulation et r!:solution du problème multi-objectif de sélection des techniques d'optimisation où il faut optimiser deux objectifs: la performance des requêtes et le coût de maintenance de l'ED. / Data Warehouses store into a single location a huge amount of data. They are interrogated by complex decisional queries called star join queries. To optimize such queries, several works propose algorithms for selecting optimization techniques such as Binary Join Indexes and Horizontal Partitioning during the DW physical design. However, these works propose static algorithms, select optimization techniques in and isolated way and focus on optimizing a single objective which is the query performance. Our main contribution in this thesis is to propose a new vision of optimization techniques selection. Our first contribution is an incremental selection that updates continuously the optimization scheme implemented on the DW, to ensure the continual optimization of queries. To deal with queries complexity increase, our second contribution is a join incremental selection of two optimization techniques which covers the optimization of a maximum number or queries and respects the optimization constraints. Finally, we note that the incremental selection generates a maintenance cost to update the optimization schemes. Thus, our third prop05ilion is to formulate and resolve a multi-objective selection problem or optimization techniques where we have two objectives to optimize : queries performance and maintenance cost of the DW.
104

Vliv složení synoviální kapaliny a topografie třecích povrchů na mazání kloubních náhrad / Effect of synovial fluid composition and surface topography modification on lubrication of joint replacements

Hekrle, Pavel January 2018 (has links)
The main objective of this diploma thesis is to determine the influence of synovial fluid compodition and the influence of surface microtextures on lubrication of hip join replacements. For all experiments, hip joint simulator based on the pendulum principle was utilized. Metal heads (CoCrMo) manufactured by B Braun company and and tailor made acetabular cups from optical glass were used as contact couples. Acetabulum dimensions were fabricated according to dimensions of real implants. Experiments with surface microtextures simulated walking cycle for 210 s and development of lubrication film over time was observed.Results have shown that all types of tested structures improved lubrication of contact area, where the best results were obtained for square and triangle shapes respectively. Second set of experiments was based on the fact, that the composition of synovial fluid of healthy people differs from the composition of patients with various stages of osteoarthritis. Therefore, experiments with different model fluids were compared, which in their composition correspond to different groups of patients. For the model fluid that corresponds to the largest number of cases, experiments with individual components and combinations thereof were subsequently performed to provide a more detailed description of how these components affect the film-forming mechanism. The results show, that a change in fluid composition of patients with osteoarthritis can have a major negative effect on fluid formation process within the pair.
105

Sestavení konsolidované účetní závěrky pro zvolený koncern / Compilation of Consolidated Financial Statements for The Selected Concern

Pekárková, Markéta January 2020 (has links)
The master´s thesis focused on the issue of consolidated financial statemant of chosen enterprise and evalution of influence on spreading consolidated unit on its economic situation. The first part of a thesis consists of theoretic solutions for preparation of financial statements. There is introduced chosen concern and evaluated its economical situation in second part. By an application of theoretic findings are formed a consolidated rules and a new financial statement spread with a new subsidiary. Finally there is evaluated a consequence of spreading consolidated unit on its economical situation.
106

Termomechanická spolehlivost pájeného připojení elektronických modulů s LTCC / Thermomechanical reliability of solder connection in electronic modules with LTCC

Krajíček, Michal January 2011 (has links)
This thesis is considered about interconnect PCB with microelectronic and electronic modules and continuing on thesis MODERN CAUSES OF ASSEMBLY MICROELECTRONICS AND ELECTRONICS MODULES. This thesis includes, definition of termomechanical strain in solder joints and description of LTCC technology. Practical part includes characterization the causes of assembly with usage chip component and proposal footprint for PCBs, modules and results of temperature cycling of tested modules.
107

ANALÝZA ZMĚNY PRÁVNÍ FORMY SPOLEČNOSTI ZPA SMART ENERGY Z S.R.O. NA A.S. / ANALYSIS OF CHANGES IN THE LEGAL FORM OF ZPA SMART ENERGY FROM THE LIMITED LIABILITY COMPANY TO THE JOINT-STOCK COMPANY

Kokorská, Markéta January 2011 (has links)
The aim of the submitted thesis is to describe the procedure of changing the legal form from limited lability copany to joint-stock copany in term of Czech legislation, including accounting and tax implications and analyze the process of transformation, economic bases and impacts on a specific company, which has undergone a change of legal status.
108

Fundamentální akciová analýza a její vliv na rozhodování v praxi / Fundamental Equities Analysis and its Effect on Decision Making in Praxis

Schiller, Jaroslav January 2014 (has links)
The subject of this thesis on fundamental equities analysis, which is considered one of the most commonly used methods for valuing securities, is to make the best investment in the chosen field into the selected equity companies. In the first part of the thesis there is a brief outline of other types of analysis together with other theoretical approaches but the main problem to be solved is the fundamental analysis. The second part is devoted to the selection and characterization of joint-stock companies of the same field and then selecting assessment indicators. The third part deals with the analysis of individual companies using selected methods of intercompany comparison from two different points of view. The final part conveys the comparison of selected methods of intercompany comparisons for both points of view and the proposal of the most suitable investment.
109

Fundamentální akciová analýza vybraných leteckých společností / Fundamental Share Analysis of Selected European Airlines

Šedaj, Jakub January 2015 (has links)
The objective of this thesis is to propose an investment recommendation in shares of selected airlines based on fundamental analysis. The theoretical part of the thesis describes the basics of investing. To select the best company there was used several intercompany comparison methods, which are based on assessment indicators. The result is an investment recommendation in the form of determining the order of profitability of individual companies.
110

Vytvoření investičního portfolia na základě fundamentální analýzy akcií / Creating of the Investment Portfolio Based on Fundamental Analysis of Stocks

Link, Radovan January 2015 (has links)
The subject of this Master´s thesis is creating of the investment portfolio based on fundamental analysis of stocks, which is considered of the most commonly used methods for valuing securities. The theoretical part of the thesis summarizes investment approaches of the most successful investors as well. In the practical part, these findings applied to the analysis by Archer-Daniels-Midland Company, Douglas Dynamics, Inc., Gentex Corp. and Union Pacific Corporation. The investment recomendation is proposed in the basis of the comparsion of the results gathered by the analysis.

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