International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / Improved processing techniques, particularly with respect to parallel computing, are the underlying focus in computer science, engineering, and industry today. Semiconductor technology is fast approaching device physical limitations. Further advances in computing performance in the near future will be realized by improved problem-solving approaches. An important issue in parallel processing is how to effectively utilize parallel computers. It is estimated that many modern supercomputers and parallel processors deliver only ten percent or less of their peak performance potential in a variety of applications. Yet, high performance is precisely why engineers build complex parallel machines. Cumulative performance losses occur due to mismatches between applications, software, and hardware. For instance, a communication system's network bandwidth may not correspond to the central processor speed or to module memory. Similarly, as Internet bandwidth is consumed by modern multimedia applications, network interconnection is becoming a major concern. Bottlenecks in a distributed environment are caused by network interconnections and can be minimized by intelligently assigning processing tasks to processing elements (PEs). Processing speeds are improved when architectures are customized for a given algorithm. Parallel processing techniques have been ineffective in most practical systems. The coupling of algorithms to architectures has generally been problematic and inefficient. Specific architectures have evolved to address the prospective processing improvements promised by parallel processing. Real performance gains will be realized when sequential algorithms are efficiently mapped to parallel architectures. Transforming sequential algorithms to parallel representations utilizing linear dependence vector mapping and subsequently configuring the interconnection network of a systolic array will be discussed in this paper as one possible approach for improved algorithm/architecture symbiosis.

Este trabalho apresenta um estudo sobre o gargalo no acesso a disco sob arquiteturas com sistemas multiprocessadores e processadores multicore e apresenta uma proposta de solução para o problema e sua implementação. A solução desenvolvida é chamada de FPA. A estratégia desenvolvida no trabalho aproveita os recursos de memória compartilhada da arquitetura e utiliza buffers de dados compartilhados entre as diversas threads das aplicações, bem como tenta otimizar o acesso ao disco rígido. Para que seja diminuída a concorrência no acesso a disco, é permitido que apenas uma thread realize leituras ou gravações no disco por vez, e nas situações de escrita é feita a sobreposição entre o processamento e o envio dos dados ao disco. As operações de escrita são realizadas por uma thread adicional, que é inicializada e gerenciada pela FPA. Foram executados diversos testes com diferentes números de threads, tamanhos de arquivo e quantidade de processamento de cálculos na aplicação. Os resultados apresentaram ganho de desempenho com a FPA em diversas situações, onde um dos fatores mais significativos para o ganho de desempenho é a quantidade de processamento existente na aplicação. De modo geral, as operações de leitura apresentaram ganho de desempenho em relação ao uso de streams nas situações onde existe pouco processamento de cálculos na aplicação, e as operações de escrita mostraram vantagem nas situações onde existe uma quantidade de processamento de cálculos maior na aplicação. Nas operações de escrita é obtido vantagem com a sobreposição entre processamento e escrita de dados. Porém, quando a quantidade de processamento de cálculos é muito alta, o tempo de espera pela gravação em disco torna-se irrisório perante o tempo gasto no processamento dos cálculos, ocasionando perda de desempenho da FPA em relação aos streams. / This work presents a study on disk access bottlenecks for multiprocessor architecture systems and also proposes a specification to solve this problem and its implementation. The developed strategy is called FPA. The developed strategy makes use of shared memory architecture and uses shared data buffers among several application threads and also tries to optimize disk access time. In order to decrease disk concurrency, is allowed to just one application thread to read/write simultaneously and processing thread operations run parallelly to disk operations. Write operations are performed by an internal thread, which is started and managed by FPA. Several tests were performed concerning different amounts of application threads instances, file sizes and computing instructions. Results show performance gain with FPA in several situations. The main factor that affects performance is the amount of computing instructions on each application. In general, read operations showed a better performance compared to use of streams in situations where there is few computing instructions in the application, and write operations showed advantages on situations where there are more computing instructions in the application. Write operations are advantageous using data writing and computing instructions overlap. However, in cases of a large amount of computing instructions compared to disk operations, the time to perform disk operations becomes too few compared to computing time, occurring FPA performance loss compared to streams.

Este trabalho apresenta um estudo sobre o gargalo no acesso a disco sob arquiteturas com sistemas multiprocessadores e processadores multicore e apresenta uma proposta de solução para o problema e sua implementação. A solução desenvolvida é chamada de FPA. A estratégia desenvolvida no trabalho aproveita os recursos de memória compartilhada da arquitetura e utiliza buffers de dados compartilhados entre as diversas threads das aplicações, bem como tenta otimizar o acesso ao disco rígido. Para que seja diminuída a concorrência no acesso a disco, é permitido que apenas uma thread realize leituras ou gravações no disco por vez, e nas situações de escrita é feita a sobreposição entre o processamento e o envio dos dados ao disco. As operações de escrita são realizadas por uma thread adicional, que é inicializada e gerenciada pela FPA. Foram executados diversos testes com diferentes números de threads, tamanhos de arquivo e quantidade de processamento de cálculos na aplicação. Os resultados apresentaram ganho de desempenho com a FPA em diversas situações, onde um dos fatores mais significativos para o ganho de desempenho é a quantidade de processamento existente na aplicação. De modo geral, as operações de leitura apresentaram ganho de desempenho em relação ao uso de streams nas situações onde existe pouco processamento de cálculos na aplicação, e as operações de escrita mostraram vantagem nas situações onde existe uma quantidade de processamento de cálculos maior na aplicação. Nas operações de escrita é obtido vantagem com a sobreposição entre processamento e escrita de dados. Porém, quando a quantidade de processamento de cálculos é muito alta, o tempo de espera pela gravação em disco torna-se irrisório perante o tempo gasto no processamento dos cálculos, ocasionando perda de desempenho da FPA em relação aos streams. / This work presents a study on disk access bottlenecks for multiprocessor architecture systems and also proposes a specification to solve this problem and its implementation. The developed strategy is called FPA. The developed strategy makes use of shared memory architecture and uses shared data buffers among several application threads and also tries to optimize disk access time. In order to decrease disk concurrency, is allowed to just one application thread to read/write simultaneously and processing thread operations run parallelly to disk operations. Write operations are performed by an internal thread, which is started and managed by FPA. Several tests were performed concerning different amounts of application threads instances, file sizes and computing instructions. Results show performance gain with FPA in several situations. The main factor that affects performance is the amount of computing instructions on each application. In general, read operations showed a better performance compared to use of streams in situations where there is few computing instructions in the application, and write operations showed advantages on situations where there are more computing instructions in the application. Write operations are advantageous using data writing and computing instructions overlap. However, in cases of a large amount of computing instructions compared to disk operations, the time to perform disk operations becomes too few compared to computing time, occurring FPA performance loss compared to streams.

iplom`s thesis is oriented on a comparison of results of fluid flow numerical modeling for case of a element type change in case CFD fluid flow modeling when elements changed in computational mesh. We want to know whether the change of the mesh elements type will have any effect on results of calculation. We want to know a size of mistakes.

In this study, the mapped Galerkin method was applied to solve the vector wave equation based on H&amp / #8722 / field and to obtain the propagation constant in x &amp / #8722 / y space. The vector wave equation was solved by the transformation of the infinite x &amp / #8722 / y plane onto a unit square. Two-dimensional Fourier series expansions were used in the solutions. Modal fields and propagation constants of dielectric waveguides were calculated. In the first part of the study, all of the calculations were made in step index fibers. Transverse magnetic fields were obtained in the u &amp / #8722 / v and x &amp / #8722 / y space through the solution of the matrix eigenvalue equation. Some graphics were plotted in the light of the results obtained. The results are found to be in accord with the results of other numerical techniques and exact solutions. After that, the propagation constant in x&amp / #8722 / y space was calculated with ease using the solution of the modal field components. In the second part of the study, the similar calculations were made in graded index fibers.

<p dir="ltr">Acoustic holography is a powerful tool in the visualization of sound fields and sound sources. It provides engineers and researchers clear insights into sound fields as well as their sound sources. Some widely-used methods include Nearfield Acoustical Holography (NAH), Statistically Optimized Nearfield Acoustic Holography (SONAH) and the Equivalent Source Method (ESM). SONAH and ESM were developed specifically to tackle the intrinsic deficiency of the Fourier-based NAH which requires that the sound field fall to negligible levels at the edges of the measurement aperture, a requirement rarely met in practice. Besides the aforementioned methods, the Inverse Boundary Element Method (IBEM) can be used, given sufficient measurements and computational resources. As useful as they are in visualizing the sound field, none of these methods can provide direct guidance on potential design modifications of the observed structure in order to unequivocally reduce sound power radiation. Acoustic radiation mode analysis has previously been primarily associated with active noise control applications. Since the radiation modes radiate sound power independently, it is only necessary to modify the surface vibration patterns so that they do not couple well with the radiation modes in order to guarantee a reduction of the radiated sound power. Since the radiation modes are orthogonal and complete, they can be used as the basis functions through which the source surface vibration can be described. Therefore, an acoustic holography method based on the acoustic radiation modes will enable the sound power ranking of the modal components of the surface vibration pattern, and in turn, point out the component(s) which should be targeted in order to reduce the overall sound power. However, use of the acoustic radiation modes in the inverse procedure comes with a price: the detailed geometry of the object to be measured must be obtained, thus enabling the calculation of acoustic radiation modes and the modal pressures. But this is not an issue for original equipment manufacturers given that almost all prototypes are now designed with CAD, as is the case with the engine example to be described next.</p><p dir="ltr">In modern engine design, downsizing and reducing weight while still providing an increased amount of power has been a general trend in recent decades. Traditionally, an engine design with superior NVH performance usually comes with a heavier, thus sturdier structure. Therefore, modern engine design requires that NVH be considered in the very early design stage to avoid modifications of engine structures at the last minute, when very few changes can be made. NVH design optimization of engine components has become more practical due to the development of computer software and hardware. However, there is still a need for smarter algorithms to draw a direct relationship between the design and the radiated sound power. At the moment, techniques based on modal acoustic transfer vectors (MATVs) have gained popularity in design optimization for their good performance in sound pressure prediction. Since MATVs are derived based on structural modes, they are not independent with respect to radiated sound power. In contrast, as noted, acoustic radiation modes are an orthogonal set of velocity distributions on the structure’s surface that contribute to the radiated sound power independently. As a result, it is beneficial to describe structural vibration in terms of acoustic radiation modes in order to identify the velocity distributions that contribute the majority of the radiated sound power. Measures can then be taken to modify the identified vibration patterns to reduce their magnitudes, which will in turn result in an unequivocal reduction of the radiated sound power. A workflow of the structural optimization procedure is proposed in this dissertation.</p><p dir="ltr">While acoustic radiation modes have great efficiencies in describing radiated acoustic power, the computation of acoustic radiation modes can be time consuming. In the last chapter of this thesis, a novel way of calculating acoustic radiation modes is proposed, which differs from the traditional singular value decomposition of the power radiation resistance matrix, and which is more efficient than previously proposed procedures. </p><p><br></p>

A regular paving (RP) is a finite succession of bisections that partitions a multidimensional box into sub-boxes using a binary tree-based data structure, with the restriction that an existing sub-box in the partition may only be bisected on its first widest side. Mapping a real value to each element of the partition gives a real-mapped regular paving (RMRP) that can be used to represent a piecewise-constant function density estimate on a multidimensional domain. The RP structure allows real arithmetic to be extended to density estimates represented as RMRPs. Other operations such as computing marginal and conditional functions can also be carried out very efficiently by exploiting these arithmetical properties and the binary tree structure. The purpose of this thesis is to explore the potential for density estimation using RPs. The thesis is structured in three parts. The first part formalises the operational properties of RP-structured density estimates. The next part considers methods for creating a suitable RP partition for an RMRP-structured density estimate. The advantages and disadvantages of a Markov chain Monte Carlo algorithm, already developed, are investigated and this is extended to include a semi-automatic method for heuristic diagnosis of convergence of the chain. An alternative method is also proposed that uses an RMRP to approximate a kernel density estimate. RMRP density estimates are not differentiable and have slower convergence rates than good multivariate kernel density estimators. The advantages of an RMRP density estimate relate to its operational properties. The final part of this thesis describes a new approach to Bayesian inference for complex models with intractable likelihood functions that exploits these operational properties.

In this work, the Traveling Salesman Problem (TSP) is discussed. The Hybrid Genetic Algorithm for solving the TSP is presented. The traveling salesman problem is formulated as follows: given matrix D=(dij)nxn of distances between n objects and the set P of permutations of the integers from 1 to n, find a permutation p=(p(1), p(2), ..., p(n)) P that minimizes. Many heuristic algorithms can be applied for the TSP. Recently, genetic algorithms (GAs) are among the advanced heuristic techniques for the combinatorial problems, like the TSP. genetic algorithms are based on the biological process of natural selection. The original concepts of GAs were developed in 1970s. Many simulations have demonstrated the efficiency of GAs on different optimization problems, among them, bin–packing, generalized assignment problem, graph partitioning, job–shop scheduling problem, set covering problem, vehicle routing. One of the main operators in GAs is the crossover (i.e. solution recombination). This operator plays a very important role by constructing competitive GAs. In this work, we investigate several crossover operators for the TSP, among them, CX (cycle crossover), PMX (partialy mapped crossover), POS (position based crossover), ER (edge recombination crossover), edge-NN (edge recombination crossover, nearest neighbour) and AP (alternating-positions crossover). Comparison of these crossover operators was performed. The results show high efficiency of the edge-NN, ER and PMX crossovers.

Submitted by MARIA JACQUELINE ATOCHE BRAVO (jacqui_mab@hotmail.com) on 2016-05-13T13:28:28Z No. of bitstreams: 1 disertacao__Jacqui.pdf: 8482416 bytes, checksum: 2325158a94282088f873ac31bbd97305 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-16T12:30:13Z (GMT) No. of bitstreams: 1 bravo_mja_me_sjrp.pdf: 8482416 bytes, checksum: 2325158a94282088f873ac31bbd97305 (MD5) / Made available in DSpace on 2016-05-16T12:30:13Z (GMT). No. of bitstreams: 1 bravo_mja_me_sjrp.pdf: 8482416 bytes, checksum: 2325158a94282088f873ac31bbd97305 (MD5) Previous issue date: 2016-03-31 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / No presente trabalho, apresenta-se uma revisão sobre os principais abordagens para análise e classificação de texturas, entre eles o descritor LBP (Local Binary Pattern), o descritor LFP (Local Fuzzy Patterm) e o descritor MSLMP (Multi-scale Local Mapped Pattern), o qual é uma extensão multiescalar do descritor LMP (Local Mapped Pattern). Resultados anteriores presentes na literatura, indicaram que o MSLMP conseguiu resultados superiores aos mencionados anteriormente. Neste trabalho propõe-se uma análise mais abrangente sobre sua viabilidade para concluir que o MSLMP é mais eficaz que os anteriores. Essa análise é feita alterando-se a Matriz de Pesos para os pixels limiarizados. Para avaliar seu desempenho, foi utilizada a base de texturas do Album de Brodatz. Após processá-la pelo descritor MSLMP, com cada uma das matrizes de Pesos propostas neste trabalho, foram comparadas as taxas de acertos alcançadas usando a distância Chi-quadrado. Resultados experimentais mostram um valor de sensibilidade melhor para o descritor MSLMP em comparação aos outros descritores presentes na literatura. / This work, presents a review about the main techniques for analysis and classification of textures, including the LBP descriptor (Local Binary Pattern), the descriptor LFP (Local Fuzzy Pattern) and the descriptor MSLMP (Multi-Scale Local Mapped Pattern), which is a multi-scale extension of the LMP method (Local Mapped Pattern). Previous results present in the literature, indicated that the MSLMP achieved better results than those mentioned above. This work proposes a more comprehensive analysis of its feasibility to conclude that this descriptor is more effective than the others. This analysis is done by changing the weight matrix for the thresholding pixels. To evaluate its performance, it was used the texture base of the Brodatz album. After processing it by the descriptor MSLMP with each of the weights matrices proposed in this work, the achieved hit rates were compared by using the distance Chi-square. Experimental results show a better sensitivity value for MSLMP descriptor in comparison of other descriptors present in the literature. / CNPq: 131632/2014-0

Submitted by EDUARDO MACHADO SILVA (eduardodz@outlook.com) on 2018-06-02T22:50:24Z No. of bitstreams: 1 Eduardo_Final.pdf: 7020230 bytes, checksum: 17f5f419806417111d44cacbf46f3f0d (MD5) / Approved for entry into archive by Elza Mitiko Sato null (elzasato@ibilce.unesp.br) on 2018-06-04T16:05:04Z (GMT) No. of bitstreams: 1 silva_em_me_sjrp.pdf: 7020230 bytes, checksum: 17f5f419806417111d44cacbf46f3f0d (MD5) / Made available in DSpace on 2018-06-04T16:05:04Z (GMT). No. of bitstreams: 1 silva_em_me_sjrp.pdf: 7020230 bytes, checksum: 17f5f419806417111d44cacbf46f3f0d (MD5) Previous issue date: 2018-04-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O Reconhecimento facial é uma das tecnologias biométricas mais utilizadas em sistemas automatizados que necessitam garantir a identidade de uma pessoa para acesso autorizado e monitoramento. A grande aceitação do uso da face tem várias vantagens sobre outras tecnologias biométricas: ela é natural, não exige equipamentos sofisticados, a aquisição de dados é baseada em abordagens não invasivas, e pode ser feito a distância, de maneira cooperativa ou não. Embora muitos estudos em reconhecimento facial tenham sido feitos, problemas com variação de iluminação, poses com oclusão facial, expressão facial e envelhecimento ainda são desafios, pois influenciam a performance dos sistemas de reconhecimento facial e motivam o desenvolvimento de novos sistemas de reconhecimento que lidam com esses problemas e sejam mais confiáveis. Este trabalho tem como objetivo avaliar a técnica de Padrões Localmente Mapeados em Multiescala (MSLMP) para o reconhecimento facial. Técnicas baseadas em algoritmos genéticos e processamento de imagens foram usadas para obter melhores resultados. Os resultados obtidos chegam a 100% de acurácia para alguns banco de dados. A base de dados MUCT ´e, em particular, bastante complexa, ela foi criada em 2010 com o objetivo de aumentar a quantidade de bancos de dados disponíveis com alta variação de iluminação, idade, posições e etnias, e por isso, ´e um banco de dados difícil quanto ao reconhecimento automático de faces. Uma nova técnica de processamento baseada na média dos níveis de cinza da base foi desenvolvida. / Facial recognition is one of the most used biometric technologies in automated systems which ensure a person’s identity for authorized access and monitoring. The acceptance of face use has several advantages over other biometric technologies: it is natural, it does not require sophisticated equipment, data acquisition is based on non-invasive approaches, and can it be done remotely, cooperatively or not. Although many facial recognition studies have been done, problems with light variation, facial occlusion, position, expression, and aging are still challenges, because they influence the performance of facial recognition systems and motivate the development of more reliable recognition systems that deal with these problems. This work aim to evaluate the Multi-scale Local Mapped Pattern (MSLMP) technique for the facial recognition. Techniques based on genetic algorithms and image processing were applied to increase the performance of the method. The obtained results reach up to 100% of accuracy for some databases. A very difficult database to deal is the MUCT database which was created in 2010 with aim of providing images with high variation of lighting, age, positions and ethnicities in the facial biometry literature, which makes it a highly difficult base in relation to automated recognition. A new processing technique was developed based on the average gray levels of the images of the database.