Orientador: Marcia A. Gomes Ruggiero / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica / Made available in DSpace on 2018-08-05T23:37:23Z (GMT). No. of bitstreams: 1 Haeser_Gabriel_M.pdf: 906525 bytes, checksum: ea7e3eb42abe6b8b451f99c4c63a3da4 (MD5) Previous issue date: 1996 / Resumo: Neste trabalho estudamos a teoria de algumas heurísticas para otimização global, e também a generalização do algoritmo genético de Aarts, Eiben e van Hee. Propomos um algoritmo para otimização global de problemas canalizados e diferenciáveis utilizando simulated annealing e o solver local GENCAN. Experimentos numéricos com o problema OVO ( Order- Value Optimization) são apresentados, e também com 28 problemas clássicos da literatura. Para problemas de otimização com restrições, apontamos idéias de como utilizar solvers locais e heurísticas globais em busca de bons algoritmos para otimização global, e propomos um algoritmo baseado em simulated annealing com solver local ALGENCAN / Abstract: In this work we study the theory behind some classical heuristics for global optimization, and a generalization of genetic algorithms from Aarts, Eiben and van Hee. We propose an algorithm for global optimization of box-constrained differentiable problems, using simulated annealing and the local solver GENCAN. Numerical experiments are presented for the OVO problem (Order-Value Optimization) and 28 classical problems. For general nonlinear programming problems, we mention some ideas of how to use local solvers and global heuristics towards good algorithms for global optimization, we also propose an algorithm based on simulated annealing with local solver ALGENCAN / Mestrado / Otimização / Mestre em Matemática Aplicada

Orientador: Katia Lucchesi Cavalca / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-09T12:41:08Z (GMT). No. of bitstreams: 1 Castro_HelioFioride_D.pdf: 2921981 bytes, checksum: 83a1aae9466f9a33a00043c950bea261 (MD5) Previous issue date: 2007 / Resumo: Neste trabalho, foi realizada a análise e validação de um modelo de sistema rotativo sustentado por mancais hidrodinâmicos. Para isto, considerou-se um modelo não-linear de mancal hidrodinâmico. A parte girante do sistema foi modelada pelo Método dos Elementos Finitos. Este modelo é capaz de simular a resposta do sistema a auto-excitação causada pelo ilme de óleo no mancal hidrodinâmico. Para calibração do modelo, um método de ajuste metaheurístico, baseado em Algoritmo Genético e Recozimento Simulado foi aplicado. Após o ajuste do modelo, compararam-se os resultados da simulação, considerando o resultado do ajuste, e resultados adquiridos na bancada experimental de teste do Laboratório de Máquinas Rotativas (DPM) na Faculdade de Engenharia Mecânica da UNICAMP. Uma especial atenção foi dada na análise dos esforços hidrodinâmicos, pois se buscou levantar os coeficientes dinâmicos lineares (coeficientes de amortecimento e rigidez) dos mancais através dos resultados obtidos experimentalmente e pelas simulações. Além disto, foram estimados coeficientes não-lineares das forças, os quais são relacionados a termos quadráticos de deslocamentos e velocidades e suas combinações, ressaltando o caratê não-linear deste tipo de mancais. Os resultados demonstraram que o modelo não-linear de mancais hidrodinâmicos é capaz de representar a instabilidade fluidoinduzida / Abstract: In this investigation, the analysis and validation of rotative system supported by hydrodynamic journal bearings was accomplished. A non-linear hydrodynamic bearing model was considered. The rotary shaft and rotor mass were modeled by The Finite Element Method. The combination of these models is able to simulate the system response to the auto-excitation caused by the oil film instabilities in the journal bearing. In order to calibrate the model, a metaheuristic method, based in Genetic Algorithm and Simulated Annealing, was applied. After the model fitting, the simulation results, taking into account the fitting results, and experimental results acquired from the experimental set-up at the Rotating Machine Laboratory in the Department of Mechanical Design of the Mechanical Engineering Faculty at UNICAMP. A special attention was directed to the hydrodynamic forces, because the dynamic bearing coefficients (stiffness and damping coefficients) were evaluated through simulated and experimental results. Moreover, non-linear coefficients of the forces were also estimated. These coefficients are related to quadratic terms of displacements and velocities and ççtheir combinations, highlighting the non-linear feature of this kind of bearing. The results showed hat the non-linear journal bearing model is able to represent the fluid-induced instability / Doutorado / Mecanica dos Sólidos e Projeto Mecanico / Doutor em Engenharia Mecânica

Orientador: Antonio Carlos Moretti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-19T18:37:54Z (GMT). No. of bitstreams: 1 Souza_JulianodaSilvade_M.pdf: 2798780 bytes, checksum: b977e17cdf141668422f1dd2f3ef4eb0 (MD5) Previous issue date: 2012 / Resumo: Neste trabalho é apresentada uma nova abordagem da heurística Simulated Annealing, no que se refere a geração de soluções na vizinhança de uma solução factível, para encontrar a solução ótima de uma formulação de programação linear inteira para o Problema de Corte de Estoque Unidimensional. O desempenho do novo algoritmo é comparado à metodologia publicada em A simulated annealing heuristic for the one-dimensional cutting stock problem apresentada em [2]. Os resultados dos experimentos computacionais indicam que essa nova abordagem, fornece soluções muito melhores em relação ao valor objetivo em tempo equivalente de execução. Além disso, uma comparação qualitativa é feita com o solver CPLEX. Para os experimentos numéricos utiliza-se o gerador de problemas CUTGEN1: A problem generator for the Standard One-dimensional Cutting Stock Problem, proposto em [6], o qual fornece um gerador de classes de problemas de acordo com os critérios de tamanho dos itens finais e demandas. Finalmente, são reportados resultados dos experimentos computacionais baseados na metodologia apresentada em [1] no artigo Guidelines for Designing and Reporting on Computational Experiments with Heuristic Methods / Abstract: This work presents a new approach to heuristic Simulated Annealing, in refers to the generation of solutions in the neighborhood of a feasible solution, to _nd the solution an optimal integer linear programming formulation for the Cutting Stock Problem One-dimensional. The performance of the new algorithm is compared to the methodology published in A simulated annealing heuristic for the one-dimensional cutting stock problem presented in [2]. The results of computational experiments indicate that this new approach provides much better solutions in relation to the objective value time equivalent execution. In addition, a qualitative comparison is made to the CPLEX solver. For the numerical experiments we use the generator of problems CUTGEN1: A problem generator for the Standard One-dimensional Cutting Stock Problem, in [6], which provides a generator classes of problems according to criteria size and demands of end items. Finally, results of experiments are reported computer-based method presented in [1] by article Guidelines for Designing and Reporting on Computational Experiments with Heuristic Methods / Mestrado / Matematica Aplicada / Mestre em Matemática Aplicada

In this thesis a simulated annealing algorithm is employed as an optimization tool for a large scale optimization problem in wireless communication. In this application, we have 100 places for transition antennas and 100 places for receivers, and also a channel between each position in both areas. Our aim is to nd, say the best 3 positions there, in a way that the channel capacity is maximized. The number of possible combinations is huge. Hence, nding the best channel will take a very long time using an exhaustive search. To solve this problem, we use a simulated annealing algorithm and estimate the best answer. The simulated annealing algorithm chooses a random element, and then from the local search algorithm, compares the selected element with its neighbourhood. If the selected element is the maximum among its neighbours, it is a local maximum. The strength of the simulated annealing algorithm is its ability to escape from local maximum by using a random mechanism that mimics the Boltzmann statistic.

This thesis reports the work of using simulated annealing to design more efficient fuzzy logic systems to model problems with associated uncertainties. Simulated annealing is used within this work as a method for learning the best configurations of type-1 and type-2 fuzzy logic systems to maximise their modelling ability. Therefore, it presents the combination of simulated annealing with three models, type-1 fuzzy logic systems, interval type-2 fuzzy logic systems and general type-2 fuzzy logic systems to model four bench-mark problems including real-world problems. These problems are: noise-free Mackey-Glass time series forecasting, noisy Mackey-Glass time series forecasting and two real world problems which are: the estimation of the low voltage electrical line length in rural towns and the estimation of the medium voltage electrical line maintenance cost. The type-1 and type-2 fuzzy logic systems models are compared in their abilities to model uncertainties associated with these problems. Also, issues related to this combination between simulated annealing and fuzzy logic systems including type-2 fuzzy logic systems are discussed. The thesis contributes to knowledge by presenting novel contributions. The first is a novel approach to design interval type-2 fuzzy logic systems using the simulated annealing algorithm. Another novelty is related to the first automatic design of general type-2 fuzzy logic system using the vertical slice representation and a novel method to overcome some parametrisation difficulties when learning general type-2 fuzzy logic systems. The work shows that interval type-2 fuzzy logic systems added more abilities to modelling information and handling uncertainties than type-1 fuzzy logic systems but with a cost of more computations and time. For general type-2 fuzzy logic systems, the clear conclusion that learning the third dimension can add more abilities to modelling is an important advance in type-2 fuzzy logic systems research and should open the doors for more promising research and practical works on using general type-2 fuzzy logic systems to modelling applications despite the more computations associated with it.

Simulated images can provide insight into the performance of optical systems, especially those with complicated features. Many modern solutions for presbyopia and cataracts feature sophisticated power geometries or diffractive elements. Some intraocular lenses (IOLs) arrive at multifocality through the use of a diffractive surface and multifocal contact lenses have a radially varying power profile. These type of elements induce simultaneous vision as well as affecting vision much differently than a monofocal ophthalmic appliance. With myriad multifocal ophthalmics available on the market it is difficult to compare or assess performance in ways that effect wearers of such appliances. Here we present software and algorithmic metrics that can be used to qualitatively and quantitatively compare ophthalmic element performance, with specific examples of bifocal intraocular lenses (IOLs) and multifocal contact lenses. We anticipate this study, methods, and results to serve as a starting point for more complex models of vision and visual acuity in a setting where modeling is advantageous. Generating simulated images of real- scene scenarios is useful for patients in assessing vision quality with a certain appliance. Visual acuity estimation can serve as an important tool for manufacturing and design of ophthalmic appliances.

The efficacy of using simulated patients (SPs) to train clinical interviewing skills in pre-practicum- and practicum-level mental health clinicians was evaluated compared to the use of traditional role-play with peers. Participants, regardless of group, engaged in a 15-minute videotaped simulated clinical session with an SP as a pre- and post-test measurement and completed five laboratory sessions, either utilizing role-play with peers or with an SP. Participants' counseling self-efficacy (CSE), measured by the Counseling Self-Estimate Inventory (COSE); state anxiety, measured by the State-Trait Anxiety Inventory, Version Y-1 (STAI Y-1); and self-reflective anxiety, measured by the Fear of Negative Evaluation scale (FNE), were assessed pre- and post-intervention. An inventory to evaluate participants' clinical competency acquisition, the Skills in Psychological Interviewing: Clinical Evaluation Scale (SPICES), was developed for the study. All participants, regardless of group, improved significantly on all measurements except fear of negative evaluation. No differences were observed between groups on outcome variables. However, all participants' pre- and post-test interaction with the SP may account for these improvements. CSE, state anxiety, and fear of negative evaluation were found to account for a small amount of variance in clinical competency acquisition in this study. The piloted SPICES scale exhibited good validity and strong inter-rater reliability estimates. Results support the efficacy of these training methods in decreasing student clinicians' anxiety levels and in increasing students' CSE and skill acquisition; furthermore, a clinical competency measure is introduced.

Self-assembly is a process of non-intrusive transformation of a system from a disordered to an ordered state. For engineering purposes, self-assembly of microscopic objects can benefit significantly from macroscopic guidance and control. This dissertation is concerned with controlling self-assembly in binary monolayers of electrically charged particles that follow basic laws of statistical mechanics. First, a simple macroscopic model is used to determine an optimal thermal control for self-assembly. The model assumes that a single rate-controlling mechanism is responsible for the formation of spatially ordered structures and that its rate follows an Arrhenius form. The model parameters are obtained using molecular dynamics simulations. The optimal control is derived in an analytical form using classical optimization methods. Two major lessons were learned from that work: (i) isothermal control was almost as effective as optimal time-dependent thermal control, and (ii) neither electrostatic interactions nor thermal control were particularly effective in eliminating voids formed during self-assembly. Accordingly, at the next stage, the focus is on temperature-pressure control under isothermal-isobaric conditions. In identifying optimal temperature and pressure conditions, several assumptions, that allow one to relate the optimal conditions to the phase diagram, are proposed. Instead of verifying the individual assumptions, the entire approach is verified using molecular dynamics simulations. It is estimated that under optimal isothermal-isobaric conditions the rate of self-assembly is about five time faster than that under optimal temperature control conditions. It is argued that the proposed approach of relating optimal conditions to the phase diagram is applicable to other systems. Further, the work reveals numerous and useful parallels between self-assembly and crystal physics, which are important to exploit for developing robust engineering self-assembly processes. / text

Redwood (Sequoia sempervirens (D. Don) Endl.) has been identified as a species with considerable potential for plantation forestry in New Zealand. Investment decisions in high value alternate species must be based on accurate wood quality and value predictions. There is an opportunity to extend non-destructive evaluation tools available to redwood growers, and to present the outputs of the growth model by log products and sawn timber. A redwood pruned buttlog sawing simulator has been developed however the simulator had not been tested with real data. Twelve redwood trees from Mangatu estate were selected for a sawing study; these logs were reconstructed and run through the sawing simulator. Computerised log processing was used to produce simulated pruned log sawing outturn from the redwood Buttlog Sawing Simulator, and results were compared to real results from a sawing study. The objective of the study was therefore to determine how well the simulator matched volume and grade out-turn from twelve logs. This study found the many inconsistencies between simulated data and real data; particularly related to log size. While this study was unsuccessful in validation of the redwood sawing simulator, it provides initial insight into the simulators strengths and short comings.

Live high - train low altitude camps can enhance endurance power at sea level by 1-2% (Levine & Stray-Gunderson, 1997). More convenient methods to simulate altitude exposure are now available, but their effects on performance are less well characterized. In this study, we investigated intermittent hypoxic training (IHT) using an Hypoxicator, a device that produces oxygen-depleted air that athletes breathe intermittently through masks in a small group at a central venue. Twelve highly-competitive, male cyclists and multi-sport athletes (IHT group) underwent IHT in two, four-week bouts separated by eight weeks. Bout one consisted of 20 one-hour exposures and bout two 18 exposures where normal and low-oxygenated air was breathed in alternating five-minute intervals. The percentage of oxygen inhaled by the subjects was adjusted to produce an oxygen saturation of the blood of 88-92% in the first week of the study, decreasing to 76-80% (equivalent to an altitude of approximately 6000m) in the final week. A control group of 13 similar athletes did not use the Hypoxicator. Performance trials and blood tests were at four-week intervals; there were 3 trials (familiarization and reliability) before use of the Hypoxicator, 3 trials after to determine the effect of simulated altitude, then a second four-week exposure and one more trial. The measures of performance were mean power in a 16-km time trial on a Kingcycle ergometer (IHT group only) and power in a lactate-threshold test at 3 mmol/L above baseline (both groups). The measures from the blood tests were haemoglobin and haematocrit. There was a gradual but erratic improvement in performance in the time trial and lactate threshold tests over the course of the study in both groups, indicating an improvement through training. Relative to the last baseline test (Trial 3), the IHT group showed a 0.6% decrease in mean power over and above the effect of training in the 16-km time trial in Trial 4, nine days after last use of IHT. There was a 0.3% increase in mean power independent of the training effect in Trial 7, after the second round of altitude exposure. Uncertainty in these changes in performance was ±3.5% (95% confidence interval). The changes in lactate threshold in trials 4 and 7 indicate a possible improvement as a result of IHT exposure. Uncertainty in these changes was ±4.0%. There were negligible changes in the haemoglobin and hematocrit of either group at any time. There was small evidence of high responders, who were probably subjects with the DD genotype for the angiotensin converting enzyme gene. The time exposed to IHT had no bearing on performance and there was no evidence "peak" in results at either four or eight weeks after exposure to IHT. In summary, four weeks of IHT exposure probably resulted in a trivial effect on 16-km time-trial performance and the effort-independent measures provided no further clear-cut evidence of a performance improvement.