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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.
31

Prevalência de disfunção temporomandibular em pacientes com Síndrome de Moebius: aspectos clínicos e imaginológicos / Prevalence of temporomandibular disorders in patients with Moebius syndrome: Clinical and imaging

Valtuir Barbosa Felix 06 July 2010 (has links)
A síndrome de Moebius (SM) é pouco freqüente e caracterizada por paralisia total ou parcial de certos pares cranianos, obrigatoriamente VI e VII, podendo associar-se a outras anormalidades. Clinicamente ocorre falta de expressão facial, hipoplasia da língua, micrognatia, lábio curto e maloclusão. Disfunção temporomandibular (DTM) não tem sido estudada em pacientes com SM. O objetivo deste estudo é conhecer a prevalência de DTM em pacientes com SM e comparar a incidência e tipo de DTM com um grupo controle. Para tanto, foi realizado um estudo clínico caso controle observacional randomizado, no Centro de Atendimento a Pacientes Especiais (CAPE) da Faculdade de Odontologia da Universidade de São Paulo (FOUSP), entre julho de 2007 e dezembro de 2009, que avaliou 101 pacientes divididos em dois grupos: Grupo de estudo (GE) composto por 36 pacientes com SM, sendo 16 do gênero masculino e 20 do gênero feminino, com idade média de 10,2 anos, variando de 3 a 18 anos de idade; e grupo controle (GC) composto por 65 pacientes sem SM e sem nenhuma deformidade crânio facial, sendo 36 do gênero masculino e 29 do gênero feminino, com idade média de 10,7 anos, variando entre 3 e 18 anos. Nossos resultados mostraram que dos 36 pacientes do GE, 20 tinham DTM ou sinal de DTM (bruxismo). Desses 20 pacientes com DTM, 15 realizaram tomografias computadorizadas de ATM (TCs). Dos 65 pacientes do GC, 8 tinham DTM ou sinal de DTM (bruxismo) e 6 concordaram em realizar as TCs. Foram obtidas imagens volumétricas multiplanares e 3D. As alterações morfológicas indicando processo degenerativo encontrado nos exames de imagem encontradas nos dois grupos foram semelhantes. Concluimos que DTM é mais freqüente em pacientes com SM e que o diagnóstico em idade tenra pode representar uma oportunidade de prevenção e tratamento precoce da doença evitando seqüelas futuras. Por esta razão a avaliação da ATM deve ser incluída no exame clínico odontológico rotineiro de pacientes com a SM. / Moebius syndrome (MS) is rare and characterized by partial or total paralysis of some cranial nerves, unavoidably VI and VII, and may be associated with other abnormalities. The clinical aspects include lack of facial expression, hypoplasia of the tongue, micrognathia, short lip and malocclusion. Temporomandibular Joint disorders (TMJ) has not been studied in patients with MS. The aim of this study is to assess the prevalence of TJD in patients with MS and to compare the incidence and type of TMJ with a control group. We conducted a case-control randomized observational clinical study at the Special Care Dentistry Center, Dental School, University of São Paulo, between July 2007 and December 2009, which evaluated 101 patients divided into two groups: Study group (SG), composed of 36 patients with MS, 16 males and 20 females, mean age 10.2 years, ranging from 3 to18 years of age, and the control group (CG) composed of 65 patients without MS and with no craniofacial deformity, 36 male and 29 female, mean age 10.7 years, ranging between 3 and 18 years. Among 36 patients of the SG, 20 had TMJ. Among them, 15 were submitted to computed tomography (CT). Of the 65 CG patients, 8 had TMJ and 6 were submitted to CTs. Volumetric multiplanar and 3D images were obtained. The morphological changes of the TMJ demonstrating the pattern of the degenerative process found in patients with SM was similar to that found in people from control group. We concluded that the prevalence of TMJ in patients with MS is higher in SM patients and the diagnosis at an early age may represent an opportunity for prevention and early treatment of disease by avoiding future sequels. For this reason the evaluation of the TMJ should be included in routine clinical dental examination of patients with MS.
32

Operadores binários para consulta de similaridade em banco de dados multimídia / Binary operators in multimidia data base

Enzo Seraphim 18 January 2006 (has links)
Os atuais gerenciadores de banco de dados não são adequados para manipulação de dados complexos; e entre eles destacamos os dados multimídia que, para agilizar as consultas usam a operação de igualdade sobre as estruturas de indexação.Operações de igualdade são pouco utilizadas em operações que envolvem dados complexos, uma vez que, a existência de dois elementos extremamente iguais é rara. Uma classe de operadores que se adequa melhor para manipulação desses dados são os operadores por similaridade. Exemplo de operadores de seleção por similaridade são a consulta por abrangência (range queries) e consulta aos vizinhos mais próximos. Exemplificando, o operador de seleção aos vizinhos mais próximos responde a consultas como, ?selecione as cinco proteínas mais parecidas pelo alinhamento da proteína Sparc (responsável pelo câncer de pele)?. Existem muitos trabalhos desenvolvidos no sentido de prover operadores de seleção por similaridade envolvendo estruturas baseadas em árvores. Entretanto, poucos estudos têm sido realizados envolvendo a utilização de operadores diferentes da seleção, por exemplo, a junção. Um operador de junção compara pares de objetos de elementos pertencentes ao domínio dos dados, ao passo que um operador de seleção recebe uma constante para a comparação dos elementos. Podemos ter assim, três operadores de junção por similaridade: operadores de junção por abrangência, por vizinhos mais próximos e sobre os pares de vizinhos mais próximos. Exemplificando, uma consulta utilizando junção por abrangência responde a consultas do tipo: ?Selecione as proteínas contidas no vírus da Hepatite B que diferem em até duas unidades de alinhamento das contidas no vírus da Hepatite C?. Este trabalho apresenta um novo método de acesso métrico em extrema quantidade de dados bem como, formas de implementação das formas de junção em estruturas métricas / The present databases managers are not adequated for complex data manipulation and among them we point out the multimedia data that to speed up the query use the equality operation on the index structure. Equality operations are not much used in operations that involve complex data sence the presence of two elements extremely equal is rare. An operator class that better manipulates these data are the similarity operators. Selection operators by similarity are the range query and the nearest neighbors query. For example, the selection operator to the nearest neighbors answers the queries like: ?select five proteins more similar by the alignment of the Sparc protein (responsible for the skin cancer)?. There are many works developed to provide similarity by selection operators envvolving structures based in trees. However, few studies have been done involving the use of different operators selection, for example, the join. A join operator compares pairs of objects of the elements belonging to the domain of the data, whereas a selection operator receives a constant to make the comparison of the elements. We can have three similarity join operators: the range join operators, the nearest neighbor and the closest neighbors pair. For instance, a query using the range join answers these kind of queries: ?Select the proteins restrained in the Hepatitis B virus that differ up to two unities from the alignment of the protein found in the Heapatitis C virus?. This work presents a new metric access method with an extreme amount of data as well as implementations forms of the join in metric structures
33

Escalonamento on-line eficiente de programas fork-join recursivos do tipo divisão e conquista em MPI / Efficent on-line scheduling of recursive fork-join programs on MPI

Mor, Stefano Drimon Kurz January 2010 (has links)
Esta Dissertação de Mestrado propõe dois novos algoritmos para tornar mais eficiente o escalonamento on-line de tarefas com dependências estritas em agregados de computadores que usam como middleware para troca de mensagens alguma implementação da MPI (até a versão 2.1). Esses algoritmos foram projetados tendo-se em vista programas construídos no modelo de programação fork/join, onde a operação de fork é usada sobre uma chamada recursiva da função. São eles: 1. O algoritmo RatMD, implementado através de uma biblioteca de primitivas do tipo map-reduce, que funciona para qualquer implementação MPI, com qualquer versão da norma. Utilizado para minimizar o tempo de execução de uma computação paralela; e 2. O algoritmo RtMPD, implementado através de um sistema distribuído sobre daemons gerenciadores de processos criados dinamicamente com a implementação MPICH2 (que implementa a MPI-2). Utilizado para permitir execuções de instâncias maiores de programas paralelos dinâmicos. Ambos se baseiam em roubo de tarefas, que é a estratégia de balanceamento de carga mais difundida na literatura. Para ambos os algoritmos apresenta-se modelagem téorica de custos. Resultados experimentais obtidos ficam dentro dos limites teóricos calculados. RatMD provê uma redução no tempo de execução de até 80% em relação ao algoritmo usual (baseado em round-robin), com manutenção do speedup próximo ao linear e complexidade espacial idêntica à popular implementação com round-robin. RtMPD mantém, no mínimo, o mesmo desempenho que a implementação canônica do escalonamento em MPICH2, dobrando-se o limite físico de processos executados simultaneamente por cada nó. / This Master’s Dissertation proposes two new algorithms for improvement on on-line scheduling of dynamic-created tasks with strict dependencies on clusters of computers using MPI (up to version 2.1) as its middleware for message-passing communication. These algorithms were built targeting programs written on the fork-join model, where the fork operation is always called over an recursive function call. They are: 1. RatMD, implemented as a map-reduce library working for any MPI implementation, on whatever norm’s version. Used for performance gain; and 2. RtMPD, implemented as a distributed system over dynamic-generated processes manager daemons with MPICH2 implentation of MPI. Used for executing larger instances of dynamic parallel programs. Both algorithms are based on the (literature consolidated) work stealing technique and have formal guarantees on its execution time and load balancing. Experimental results are within theoretical bounds. RatMD shows an improvement on the performance up to 80% when paired with more usual algorithms (based on round-robin strategy). It also provides near-linear speedup and just about the same space-complexity on similar implementations. RtMPD keeps, at minimum, the very same performance of the canonical MPICH2 implementation, near doubling the physical limit of simultaneous program execution per cluster node.
34

An Investigation of the Properties of Join Geometry

Giegerich, Louis John, Jr. 01 May 1963 (has links)
This paper presents a proof that the classical geometry as stated by Karol Borsuk [1] follows from the join geometry of Walter Prenowitz [2]. The approach taken is to assume the axioms of Prenowitz. Using these as the foundation, the theory of join geometry is then developed to include such ideas as 'convex set', 'linear set', the important concept of 'dimension', and finally the relation of 'betweenness'. The development is in the form of definitions with the important extensions given in the form of theorems. With a firm foundation of theorems in the join geometry, the axioms of classical geometry are examined, and then they are proved as theorems or modified and proved as theorems. The basic notation to be used is that of set theory. No distinction is made between the set consisting of a single element and the element itself. Thus the notation for set containment is ⊂, and is used to denote element containment also. The set containing no elements, or the empty set, is denoted by Ø, The set of points belonging to at least one of the sets under consideration is called union, denoted ∪. The set of points belonging to each of the sets under consideration is called the intersection and denoted by ∩. Any other notation used will be defined at the first usage.
35

Transactional pointcuts for aspect-oriented programming

Sadat Kooch Mohtasham, Seyed Hossein 06 1900 (has links)
In dynamic pointcut-advice join point models of Aspect-Oriented Programming (AOP), join points are typically selected and advised independently of each other. That is, the relationships between join points are not considered in join point selection and advice. But these inter-relationships are key to the designation and advice of arbitrary pieces of code when modularizing concerns such as exception handling and synchronization. Without a mechanism for associating join points, one must instead refactor (if possible) into one method the two or more related join points that are to be advised together. In practice, join points are often not independent. Instead, they form part of a higher-level operation that implements the intent of the developer (e.g. managing a resource). This relationship should be made more explicit. We extend the dynamic pointcut-advice join point model to make possible the designation, reication, and advice of interrelated join points. The Transactional Pointcut (transcut), which is a realization of this extended model, is a special join point designator that selects sets of interrelated join points. Each match of a transcut is a set of join points that are related through control ow, dataow, or both. This allows transcuts to dene new types of join points (pieces of computation) by capturing the key points of a computation and to provide effective access for their manipulation (i.e. advice). Essentially, transcuts almost eliminate the need for refactoring to expose join points, which is shown by others to have a signicant negative effect on software quality. The transcut construct was implemented as an extension to the AspectJ language and integrated into the AspectBench compiler. We used transcuts to modularize the concern of exception handling in two real-world software systems. The results show that transcuts are effective in designating target join points without unnecessary refactorings, even when the target code is written obliviously to the potential aspectization.
36

Habanero-Scala: A Hybrid Programming model integrating Fork/Join and Actor models

Imam, Shams 24 July 2013 (has links)
This study presents a hybrid concurrent programming model combining the previously developed Fork-Join model (FJM) and Actor model (AM). With the advent of multi-core computers, there is a renewed interest in programming models that reduce the burden of reasoning about and writing efficient concurrent programs. The proposed hybrid model shows how the divide-and-conquer approach of the FJM and the no-shared mutable state and event-driven philosophy of the AM can be combined to solve certain classes of problems more efficiently and productively than either of the aforementioned models individually. The hybrid model adds actor creation and coordination to into the FJM, while also enabling parallelization within actors. This study uses the Habanero-Java and Scala programming languages as the base for the FJM and AM respectively, and provides an implementation of the hybrid model as an extension of the Scala language called Habanero-Scala. The hybrid model adds to the foundations of parallel programs, and to the tools available for the programmer to aid in productivity and performance while developing parallel software.
37

XQuery Query Processing in Relational Systems

Chen, Yingwen January 2004 (has links)
With the rapid growth of XML documents to serve as a popular and major media for storage and interchange of the data on the Web, there is an increasing interest in using existing traditional relational database techniques to store and/or query XML data. Since XQuery is becoming a standard XML query language, significant effort has been made in developing an efficient and comprehensive XQuery-to-SQL query processor. In this thesis, we design and implement an <em>XQuery-to-SQL Query Processor</em> based on the <em>Dynamic Intervals</em> approach. We also provide a comprehensive translation for XQuery basic operations and FLWR expressions. The query processor is able to translate a complex XQuery query, which might include arbitrarily composed and nested FLWR expressions, basic functions, and element constructors, into a single SQL query for RDBMS and a physical plan for the <em>XQuery-enhanced Relational Engine</em>. In order to produce efficient and concise SQL queries, succinct XQuery to SQL translation templates and the optimization algorithms for the SQL query generation are proposed and implemented. The preferable <em>merge-join</em> approach is also proposed to avoid the inefficient <em>nested-loop</em> evaluation for FLWR expressions. <em>Merge-join</em> patterns and query rewriting rules are designed to identify XQuery fragments that can utilize the efficient <em>merge-join</em> evaluation. Proofs of correctness of the approach are provided in the thesis. Experimental results justify the correctness of our work.
38

Efficient Range and Join Query Processing in Massively Distributed Peer-to-Peer Networks

Wang, Qiang January 2008 (has links)
Peer-to-peer (P2P) has become a modern distributed computing architecture that supports massively large-scale data management and query processing. Complex query operators such as range operator and join operator are needed by various distributed applications, including content distribution, locality-aware services, computing resource sharing, and many others. This dissertation tackles a number of problems related to range and join query processing in P2P systems: fault-tolerant range query processing under structured P2P architecture, distributed range caching under unstructured P2P architecture, and integration of heterogeneous data under unstructured P2P architecture. To support fault-tolerant range query processing so as to provide strong performance guarantees in the presence of network churn, effective replication schemes are developed at either the overlay network level or the query processing level. To facilitate range query processing, a prefetch-based caching approach is proposed to eliminate the performance bottlenecks incurred by those data items that are not well cached in the network. Finally, a purely decentralized partition-based join query operator is devised to realize bandwidth-efficient join query processing under unstructured P2P architecture. Theoretical analysis and experimental simulations demonstrate the effectiveness of the proposed approaches.
39

Packing Directed Joins

Williams, Aaron January 2004 (has links)
Edmonds and Giles conjectured that the maximum number of directed joins in a packing is equal to the minimum weight of a directed cut, for any weighted directed graph. This is a generalization of Woodall's Conjecture (which is still open). Schrijver found the first known counterexample to the Edmonds-Giles Conjecture, while Cornuejols and Guenin found the next two. In this thesis we introduce new counterexamples, and prove that all minimal counterexamples of a certain type have now been found.
40

XQuery Query Processing in Relational Systems

Chen, Yingwen January 2004 (has links)
With the rapid growth of XML documents to serve as a popular and major media for storage and interchange of the data on the Web, there is an increasing interest in using existing traditional relational database techniques to store and/or query XML data. Since XQuery is becoming a standard XML query language, significant effort has been made in developing an efficient and comprehensive XQuery-to-SQL query processor. In this thesis, we design and implement an <em>XQuery-to-SQL Query Processor</em> based on the <em>Dynamic Intervals</em> approach. We also provide a comprehensive translation for XQuery basic operations and FLWR expressions. The query processor is able to translate a complex XQuery query, which might include arbitrarily composed and nested FLWR expressions, basic functions, and element constructors, into a single SQL query for RDBMS and a physical plan for the <em>XQuery-enhanced Relational Engine</em>. In order to produce efficient and concise SQL queries, succinct XQuery to SQL translation templates and the optimization algorithms for the SQL query generation are proposed and implemented. The preferable <em>merge-join</em> approach is also proposed to avoid the inefficient <em>nested-loop</em> evaluation for FLWR expressions. <em>Merge-join</em> patterns and query rewriting rules are designed to identify XQuery fragments that can utilize the efficient <em>merge-join</em> evaluation. Proofs of correctness of the approach are provided in the thesis. Experimental results justify the correctness of our work.

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