Feedforward neural networks are massively parallel computing structures that have the capability of universal function approximation. The most prevalent realisation of neural nets is in the form of an algorithm implemented in a computer program. Neural networks as computer programs lose the inher- ent parallism. Parallism can only be recovered by executing the program on an expensive parallel digital computer. Achievement of the inherent massive parallelism at a lower cost requires direct hardware realisation of the neural net. Such hardware has been developed jointly by QUT and the Heinz Nixdorf Institute (Germany) called the Local Cluster Neural Network (LCNN) chip. But this neural net chip lacks the capability of in-circuit learning or on-chip training. The weights for the analogue LCNN network have to be computed o® chip on a digital computer. Based on the previous work, this research focuses on the Local Cluster Neu- ral Network and its analogue chip. The characteristic of the LCNN chip was measured exhaustively and its behaviours were compared to the theoretical functionality of the LCNN. To overcome the manufacturing °uctuations and deviations presented in analogue circuits, we used chip-in-the-loop strategy for training of the LCNN chip. A new training algorithm: Probabilistic Random Weight Change for the chip-in-the-loop training for function approximation. In order to implement the LCNN analogue chip with on-chip training, two training algorithms are studied in on-line training mode in simulations: the Probabilistic Random Weight Change (PRWC) algorithm and the modified Gradient Descent (GD) algorithm. The circuits design for the PRWC on-chip training and the GD on-chip training are outlined. These two methods are compared for their training performance and the complexity of their circuits. This research provides the foundation for the next version of LCNN analogue hardware implementation.

Item response theory (IRT) is a newer and improved theory compared to the classical measurement theory. The fully Bayesian approach shows promise for IRT models. However, it is computationally expensive, and therefore is limited in various applications. It is important to seek ways to reduce the execution time and a suitable solution is the use of high performance computing (HPC). HPC offers considerably high computational power and can handle applications with high computation and memory requirements. In this work, we have modified the existing fully Bayesian algorithm for 2PNO IRT models so that it can be run on a high performance parallel machine. With this parallel version of the algorithm, the empirical results show that a speedup was achieved and the execution time was reduced considerably.

Item response theory (IRT) is a newer and improved theory compared to the classical measurement theory. The fully Bayesian approach shows promise for IRT models. However, it is computationally expensive, and therefore is limited in various applications. It is important to seek ways to reduce the execution time and a suitable solution is the use of high performance computing (HPC). HPC offers considerably high computational power and can handle applications with high computation and memory requirements. In this work, we have applied two different parallelism methods to the existing fully Bayesian algorithm for 2PNO IRT models so that it can be run on a high performance parallel machine with less communication load. With our parallel version of the algorithm, the empirical results show that a speedup was achieved and the execution time was considerably reduced.

Orientador: José Márcio Machado / Banca: Liria Matsumoto Sato / Banca: Renata Spolon Lobato / Resumo: A biologia, como uma ciência bastante desenvolvida, foi dividida em diversas areas, dentre elas, a genética. Esta area passou a crescer em importância nos ultimos cinquenta anos devido aos in umeros benefícios que ela pode trazer, principalmente, aos seres humanos. Como a gen etica passou a apresentar problemas com grande complexidade de resolução estratégias computacionais foram agregadas a ela, surgindo assim a bioinform atica. A bioinformática desenvolveu-se de forma bastante signi cativa nos ultimos anos e esse desenvolvimento vem se acentuando a cada dia, devido ao aumento da complexidade dos problemas genômicos propostos pelos biólogos. Assim, os cientistas da computação têm se empenhado no desenvolvimento de novas técnicas computacionais para os biólogos, principalmente no que diz respeito as estrat egias para alinhamentos m ultiplos de sequências. Quando as sequências estão alinhadas, os biólogos podem realizar mais inferências sobre elas, principalmente no reconhecimento de padrões que e uma outra area interessante da bioinformática. Atrav es do reconhecimento de padrãoes, os bi ologos podem identicar pontos de alta signi cância (hot spots) entre as sequências e, consequentemente, pesquisar curas para doençass, melhoramentos genéticos na agricultura, entre outras possibilidades. Este trabalho traz o desenvolvimento e a comparação entre duas técnicas computacionais para o alinhamento m ultiplo de sequências. Uma e baseada na técnica de alinhamento múltiplo de sequências progressivas pura e a outra, e uma técnica de alinhamento múltiplo de sequências otimizada a partir da heurística de colônia de formigas. Ambas as técnicas adotam em algumas de suas fases estratégias de paralelismo, focando na redu c~ao do tempo de execução dos algoritmos. Os testes de desempenho e qualidade dos alinhamentos que foram conduzidos com as duas estrat egias... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Biology as an enough developed science was divided in some areas, and genetics is one of them. This area has improved its relevance in last fty years due to the several bene ts that it can mainly bring to the humans. As genetics starts to show problems with hard resolution complexity, computational strategies were aggregated to it, leading to the start of the bioinformatics. The bioinformatics has been developed in a signi cant way in the last years and this development is accentuating everyday due to the increase of the complexity of the genomic problems proposed by biologists. Thus, the computer scientists have committed in the development of new computational techniques to the biologists, mainly related to the strategies to multiple sequence alignments. When the sequences are aligned, the biologists can do more inferences about them mainly in the pattern recognition that is another interesting area of the bioinformatics. Through the pattern recognition, the biologists can nd hot spots among the sequences and consequently contribute for the cure of diseases, genetics improvements in the agriculture and many other possibilities. This work brings the development and the comparison between two computational techniques for the multiple sequence alignments. One is based on the pure progressive multiple sequence alignment technique and the other one is an optimized multiple sequence alignment technique based on the ant colony heuristics. Both techniques take on some of its stages of parallel strategies, focusing on reducing the execution time of algorithms. Performance and quality tests of the alignments were conducted with both strategies and showed that the optimized approach presents better results when it is compared with the pure progressive approach. Biology as an enough developed science was divided in some areas, and genetics is one of them. This area has improved... (Complete abstract click electronic access below) / Mestre

This work investigates how certain processor architectures can affectthe implementation and performance of a parallel programming model.The Ericsson Many-Core Architecture (EMCA) is compared and contrastedto general-purpose multicore processors, highlighting differencesin their memory systems and processor cores. A proof-of-conceptimplementation of the Concurrency Building Blocks (CBB) programmingmodel is developed for x86-64 using MPI. Benchmark tests showhow CBB on EMCA handles compute-intensive and memory-intensivescenarios, compared to a high-end x86-64 machine running the proofof-concept implementation. EMCA shows its strengths in heavy computationswhile x86-64 performs at its best with high degrees of datareuse. Both systems are able to utilize locality in their memory systemsto achieve great performance benefits.

This research focuses on the development of a solution strategy for the optimization of large-scale dynamic systems under uncertainty. Uncertainty resides naturally within the external forces posed to the system or from within the system itself. For example, in chemical process systems, external inputs include flow rates, temperatures or compositions; while internal sources include kinetic or mass transport parameters; and empirical parameters used within thermodynamic correlations and expressions. The goal in devising a dynamic optimization approach which explicitly accounts for uncertainty is to do so in a manner which is computationally tractable and is general enough to handle various types and sources of uncertainty. The approach developed in this thesis follows a so-called multiperiod technique whereby the infinite dimensional uncertainty space is discretized at numerous points (known as periods or scenarios) which creates different possible realizations of the uncertain parameters. The resulting optimization formulation encompasses an approximated expected value of a chosen objective functional subject to a dynamic model for all the generated realizations of the uncertain parameters. The dynamic model can be solved, using an appropriate numerical method, in an embedded manner for which the solution is used to construct the optimization formulation constraints; or alternatively the model could be completely discretized over the temporal domain and posed directly as part of the optimization formulation. Our approach in this thesis has mainly focused on the embedded model technique for dynamic optimization which can either follow a single- or multiple-shooting solution method. The first contribution of the thesis investigates a combined multiperiod multiple-shooting dynamic optimization approach for the design of dynamic systems using ordinary differential equation (ODE) or differential-algebraic equation (DAE) process models. A major aspect of this approach is the analysis of the parallel solution of the embedded model within the optimization formulation. As part of this analysis, we further consider the application of the dynamic optimization approach to several design and operation applications. Another vmajor contribution of the thesis is the development of a nonlinear programming (NLP) solver based on an approach that combines sequential quadratic programming (SQP) with an interior-point method (IPM) for the quadratic programming subproblem. A unique aspect of the approach is that the inherent structure (and parallelism) of the multiperiod formulation is exploited at the linear algebra level within the SQP-IPM nonlinear programming algorithm using an explicit Schur-complement decomposition. Our NLP solution approach is further assessed using several static and dynamic optimization benchmark examples. / Thesis / Doctor of Philosophy (PhD)

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With advanced subsonic transports and military aircraft operating in the transonic regime, it is becoming important to determine the effects of the coupling between aerodynamic loads and elastic forces. Since aeroelastic effects can contribute significantly to the design of these aircraft, there is a strong need in the aerospace industry to predict these aero-structure interactions computationally. To perform static aeroelastic analysis in the transonic regime, high fidelity computational fluid dynamics (CFD) analysis tools must be used in conjunction with high fidelity computational structural dynamics (CSD)analysis tools due to the nonlinear behavior of the aerodynamics in the transonic regime. There is also a need to be able to use a wide variety of CFD and CSD tools to predict these aeroelastic effects in the transonic regime. Because source codes are not always available, it is necessary to couple the CFD and CSD codes without alteration of the source codes. In this study, an aeroelastic coupling procedure is developed which will perform static aeroelastic analysis using any CFD and CSD code with little code integration. The aeroelastic coupling procedure is demonstrated on an F/A-18 Stabilator using NASTD (an in-house McDonnell Douglas CFD code)and NASTRAN. In addition, the Aeroelastic Research Wing (ARW-2) is used for demonstration of the aeroelastic coupling procedure by using ENSAERO (NASA Ames Research Center CFD code) and a finite element wing-box code (developed as a part of this research). The results obtained from the present study are compared with those available from an experimental study conducted at NASA Langley Research Center and a study conducted at NASA Ames Research Center using ENSAERO and modal superposition. The results compare well with experimental data. In addition, parallel computing power is used to investigate parallel static aeroelastic analysis because obtaining an aeroelastic solution using CFD/CSD methods is computationally intensive. A parallel finite element wing-box code is developed and coupled with an existing parallel Euler code to perform static aeroelastic analysis. A typical wing-body configuration is used to investigate the applicability of parallel computing to this analysis. Performance of the parallel aeroelastic analysis is shown to be poor; however with advances being made in the arena of parallel computing, there is definitely a need to continue research in this area. / Ph. D.