Este trabalho apresenta a técnica de Algoritmo Genético para apoiar o processo de modelagem e simulação de sistemas complexos. Tal técnica pode ser vista como uma opção as técnicas tradicionais de modelagem e análise dos dados de simulação, simplificando todo esse processo, por suas características de simplicidade e generalidade, não exigindo conhecimento especifico do domínio do problema. É apresentada uma ferramenta computacional - SimAG - baseada em Algoritmo Genético para modelagem e simulação de sistemas dessa natureza. Um exemplo de aplicação e estudado, onde pode ser constatada a viabilidade da utilização da técnica no processo de simulação / This work presents the Genetic Algorithm technique supporting the process of complex systems modeling and simulation. Such technique can be seen as an option to both the traditional modeling and the simulation data analysis techniques. Due to its inherent simplicity and generic application, it simplifies the whole process of simulation, demanding no specific knowledge over the problem domain. A genetic algorithm based computational tool - SimAG - for the modeling and simulation of such systems is here presented, and an example of its use is analyzed, thus demonstrating the feasibility of this new technique application in simulation processes

Over the last decade advances and innovations from Silicon Photonics technology were observed in the telecommunications and computing industries. This technology which employs Silicon as an optical medium, relies on current CMOS micro-electronics fabrication processes to enable medium scale integration of many nano-photonic devices to produce photonic integrated circuitry. However, other fields of research such as optical sensor processing can benefit from silicon photonics technology, specially in sensors where the physical measurement is wavelength encoded. In this research work, we present a design and application of a thermally tuned silicon photonic device as an optical sensor interrogator. The main device is a micro-ring resonator filter of 10 $\mu m$ of diameter. A photonic design toolkit was developed based on open source software from the research community. With those tools it was possible to estimate the resonance and spectral characteristics of the filter. From the obtained design parameters, a 7.8 x 3.8 mm optical chip was fabricated using standard micro-photonics techniques. In order to tune a ring resonance, Nichrome micro-heaters were fabricated on top of the device. Some fabricated devices were systematically characterized and their tuning response were determined. From measurements, a ring resonator with a free-spectral-range of 18.4 nm and with a bandwidth of 0.14 nm was obtained. Using just 5 mA it was possible to tune the device resonance up to 3 nm. In order to apply our device as a sensor interrogator in this research, a model of wavelength estimation using time interval between peaks measurement technique was developed and simulations were carried out to assess its performance. To test the technique, an experiment using a Fiber Bragg grating optical sensor was set, and estimations of the wavelength shift of this sensor due to axial strains yield an error within 22 pm compared to measurements from spectrum analyzer. Results from this study implies that signals from FBG sensors can be processed with good accuracy using a micro-ring device with the advantage of ts compact size, scalability and versatility. Additionally, the system also has additional applications such as processing optical wavelength shifts from integrated photonic sensors and to be able to track resonances from laser sources.

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The South African economy, which is largely based on heavy industry such as minerals extraction and processing, is by nature very energy intensive. Based on the abundance of coal resources, electricity in South Africa remains amongst the cheapest in the world. Whilst the low electricity price has contributed towards a competitive position, it has also meant that our existing electricity supply is often taken for granted. The economic and environmental benefits of energy efficiency have been well documented. Worldwide, nations are beginning to face up to the challenge of sustainable energy - in other words to alter the way that energy is utilised so that social, environmental and economic aims of sustainable development are supported. South Africa as a developing nation recognises the need for energy efficiency, as it is the most cost effective way of meeting the demands of sustainable development. South Africa, with its unique economic, environmental and social challenges, stands to benefit the most from implementing energy efficiency practices. The Energy Efficiency Strategy for South Africa takes its mandate from the South African White Paper on Energy Policy. It is the first consolidated governmental effort geared towards energy efficiency practices throughout South Africa. The strategy allows for the immediate implementation of low-cost and no-cost interventions, as well as those higher-cost measures with short payback periods. An initial target has been set for an across sector energy efficiency improvement of 12% by 2014. Thermal and energy system simulation is globally recognised as one of the most effective and powerful tools to improve overall energy efficiency. However, because of the usual extreme mathematical nature of most simulation algorithms, coupled with the historically academic environment in which most simulation software is developed, valid perceptions exist that system simulation is too time consuming and cumbersome. It is also commonly known that system simulation is only effective in the hands of highly skilled operators, which are specialists in their prospective fields. Through previous work done in the field, and the design of a dynamic thermal and energy system simulation scheme for cross industry applications, it was shown that system simulation has evolved to such an extent that these perceptions are not valid any more. The South African mining and commercial building industries are two of the major consumers of electricity within South Africa. By improving energy efficiency practices within the building and mining industry, large savings can be realised. An extensive investigation of the literature showed that no general suitable computer simulation software for cross industry mining and building thermal and energy system simulation could be found. Because the heating, ventilation and air conditioning (HVAC) of buildings, closely relate to the ventilation and cooling systems of mines, valuable knowledge from this field was used to identify the requirements and specifications for the design of a new single cross industry dynamic integrated thermal and energy system simulation tool. VISUALQEC was designed and implemented to comply with the needs and requirements identified. A new explicit system component model and explicit system simulation engine, combined with a new improved simulation of mass flow through a system procedure, suggested a marked improvement on overall simulation stability, efficiency and speed. The commercial usability of the new simulation tool was verified for building applications by doing an extensive building energy savings audit. The new simulation tool was further verified by simulating the ventilation and cooling (VC) and underground pumping system of a typical South African gold mine. Initial results proved satisfactory but, more case studies to further verify the accuracy of the implemented cross industry thermal and energy system simulation tool are needed. Because of the stable nature of the new VISUALQEC simulation engine, the power of the simulation process can be further extended to the mathematical optimisation of various system variables. In conclusion, this study highlighted the need for new simulation procedures and system designs for the successful implementation and creation of a single dynamic thermal and energy system simulation tool for cross industry applications. South Africa should take full advantage of the power of thermal and energy system simulation towards creating a more energy efficient society. / Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2005.

The South African economy, which is largely based on heavy industry such as minerals extraction and processing, is by nature very energy intensive. Based on the abundance of coal resources, electricity in South Africa remains amongst the cheapest in the world. Whilst the low electricity price has contributed towards a competitive position, it has also meant that our existing electricity supply is often taken for granted. The economic and environmental benefits of energy efficiency have been well documented. Worldwide, nations are beginning to face up to the challenge of sustainable energy - in other words to alter the way that energy is utilised so that social, environmental and economic aims of sustainable development are supported. South Africa as a developing nation recognises the need for energy efficiency, as it is the most cost effective way of meeting the demands of sustainable development. South Africa, with its unique economic, environmental and social challenges, stands to benefit the most from implementing energy efficiency practices. The Energy Efficiency Strategy for South Africa takes its mandate from the South African White Paper on Energy Policy. It is the first consolidated governmental effort geared towards energy efficiency practices throughout South Africa. The strategy allows for the immediate implementation of low-cost and no-cost interventions, as well as those higher-cost measures with short payback periods. An initial target has been set for an across sector energy efficiency improvement of 12% by 2014. Thermal and energy system simulation is globally recognised as one of the most effective and powerful tools to improve overall energy efficiency. However, because of the usual extreme mathematical nature of most simulation algorithms, coupled with the historically academic environment in which most simulation software is developed, valid perceptions exist that system simulation is too time consuming and cumbersome. It is also commonly known that system simulation is only effective in the hands of highly skilled operators, which are specialists in their prospective fields. Through previous work done in the field, and the design of a dynamic thermal and energy system simulation scheme for cross industry applications, it was shown that system simulation has evolved to such an extent that these perceptions are not valid any more. The South African mining and commercial building industries are two of the major consumers of electricity within South Africa. By improving energy efficiency practices within the building and mining industry, large savings can be realised. An extensive investigation of the literature showed that no general suitable computer simulation software for cross industry mining and building thermal and energy system simulation could be found. Because the heating, ventilation and air conditioning (HVAC) of buildings, closely relate to the ventilation and cooling systems of mines, valuable knowledge from this field was used to identify the requirements and specifications for the design of a new single cross industry dynamic integrated thermal and energy system simulation tool. VISUALQEC was designed and implemented to comply with the needs and requirements identified. A new explicit system component model and explicit system simulation engine, combined with a new improved simulation of mass flow through a system procedure, suggested a marked improvement on overall simulation stability, efficiency and speed. The commercial usability of the new simulation tool was verified for building applications by doing an extensive building energy savings audit. The new simulation tool was further verified by simulating the ventilation and cooling (VC) and underground pumping system of a typical South African gold mine. Initial results proved satisfactory but, more case studies to further verify the accuracy of the implemented cross industry thermal and energy system simulation tool are needed. Because of the stable nature of the new VISUALQEC simulation engine, the power of the simulation process can be further extended to the mathematical optimisation of various system variables. In conclusion, this study highlighted the need for new simulation procedures and system designs for the successful implementation and creation of a single dynamic thermal and energy system simulation tool for cross industry applications. South Africa should take full advantage of the power of thermal and energy system simulation towards creating a more energy efficient society. / Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2005.

A utilização de um modelo computacional para simular o consumo energético de edificações para diferentes fins tornou-se prática comum. Entretanto, para que suas finalidades sejam válidas para prédios em fase de operação é necessário que a simulação passe por uma fase denominada calibração, ou seja, ajuste de seus parâmetros de entrada para verificar que seu resultado esteja coerente com a realidade. Dado esta necessidade, este trabalho tem como objetivo a calibração da energia elétrica simulada por um modelo EnergyPlus do Hospital Universitário da Universidade de São Paulo (HU-USP). Na busca por este objetivo, faz-se a revisão do estado da arte sobre metodologias de calibração baseadas em evidência, ou seja, no qual os ajustes nos parâmetros de entradas baseiam-se em informações coletadas acerca do edifício real. Pela comparação destas metodologias, selecionou-se aquela proposta por Raftery, Keane e O donnell (2011) cuja aplicação mostrou-se mais generalizada para diferentes tipologias de edifícios. As medições disponíveis do HU-USP contra o qual as simulações foram confrontadas foram: consumo de prédio, consumo de uma das duas centrais de água gelada do prédio e medição de 16 equipamentos modulares do tipo split. Os indicadores estatísticos resultantes da comparação destas medições revelaram que, ao final do processo de calibração, apenas o consumo do prédio pôde ser considerado calibrado. A partir da simulação calibrada foram avaliadas quatro alternativas de eficiência energética, duas no sistema de iluminação e duas no sistema de climatização. As experiências acumuladas na calibração da simulação do HU-USP e a identificação de melhores práticas na literatura permitiram, ao final, a elaboração de uma nova metodologia que engloba a abordagem de um prédio com as características de edificações públicas brasileiras. / The use of a computational model for simulation of the energy consumption of buildings for different goals has become common practice. However, in order to use it to simulate operating buildings, it is necessary that the simulation undergoes a process called calibration. This means adjusting simulation input to certify that its output consistently represents the reality. This work objective is to calibrate the electric energy simulated by an energy model of the University Hospital of the University of São Paulo (HU-USP). The state of the art is reviewed in search of evidence-based calibration methodologies. This type of methodologies uses data collected from the real building to change the simulation input. It was selected the methodology proposed by Raftery, Keane and O donnell (2011) which was evaluated as the most generalized approach between the methodologies reviewed. The available measurements of HU-USP against which the simulations were confronted were: building electricity consumption, one (of the two) chilled water plant electricity consumption and the electricity measurement of 16 split type air conditioner. The statistical indicators resulted in comparisons of the measurements revealed, at the end of the calibration process, that only the consumption of the building could be considered calibrated. From the calibrated calibration, four energy efficiency alternatives were simulated, two concerning the lighting system and two concerning the air conditioning system. From the experience accumulated through the calibration of HU-USP electric energy consumption simulation and the identification of the best practices in the literature, it was elaborated a new methodology that includes an approach that deal with brazilian public buildings features.

<div>Bike sharing system (BSS) is growing worldwide. Although bike sharing is viewed as a sustainable transportation mode, it still has environmental footprints from its operation (e.g., bike rebalancing using automobiles) and upstream impacts (e.g., bike and docking station manufacturing). Thus, evaluating the environmental impacts of a BSS from the life cycle perspective is vital to inform decision making for the system design and operation. In this study, we conducted a comparative life cycle assessment (LCA) of station-based and dock-less BSS in the U.S. The results show that dock-less BSS has a greenhouse gas (GHG) emissions factor of 118 g CO2-eq/bike-km in the base scenario, which is 82% higher than the station-based system. Bike rebalancing is the main source of GHG emissions, accounting for 36% and 73% of the station-based and dock-less systems, respectively. However, station-based BSS has 54% higher total normalized environmental impacts (TNEI), compared to dock-less BSS. The dock manufacturing dominants the TNEI (61%) of station-based BSS and the bike manufacturing contributes 52% of TNEI in dock-less BSS. BSS can also bring environmental benefits through substituting different transportation modes. Car trip replacement rate is the most important factor. The results suggest four key approaches to improve BSS environmental performance: 1) optimizing the bike distribution and rebalancing route or repositioning bikes using more sustainable approaches, 2) incentivizing more private car users to switch to using BSSs, 3) prolonging lifespans of docking infrastructure to significantly reduce the TNEI of station-based systems, and 4) increasing the bike utilization efficiency to improve the environmental performance of dock-less systems.</div><div>To improve the design of current BSS from the life cycle perspective, we first proposed a simulation framework to find the minimal fleet size and their layout of the system. Then we did a tradeoff analysis between bike fleet size and the rebalancing frequency to investigate the GHG emission if we rebalance once, twice and three times a day. The optimal BSS design and operation strategies that can minimize system GHG emission are identified for a dock-less system in Xiamen, China. The results show that at most 15% and 13% of the existing fleet size is required to serve all the trip demand on weekday and weekend, if we have a well-designed bike layout. The tradeoff analysis shows that the GHG emission may increase if we continue to reduce the fleet size through more frequent rebalancing work. Rebalancing once a day during the night is the optimal strategy in the base scenario. We also tested the impacts of other key factors (e.g., rebalancing vehicle fleet size, vehicle capacity and multiple depots) on results. The analysis results showed that using fewer vehicles with larger capacity could help to further reduce the GHG emission of rebalancing work. Besides, setting 3 depots in the system can help to reduce 30% of the GHG emission compared with 1-depot case, which benefits from the decrease of the commuting trip distance between depot and the serve region.</div>

Ce travail propose l’investigation d’une approche physique 0D/1D modélisant les brûleurs de turbines à gaz, prenant en compte l’évaporation du carburant, la turbulence, la combustion, et permet la représentation de zones de dilution et l’implémentation de modèles de chimie des polluants. Il s’agit de sous-modèles répartis dans des composants assemblables dans un environnement numérique multi-domaines basé sur le formalisme de Bond Graph. Ceci permet, par exemple, l’assemblage de plusieurs volumes ouverts en un tube à flamme, l’ajout d’un compresseur et d’une turbine, ou bien aussi d’intégrer des chaînes de commande afin de représenter un hélicoptère complet. L’originalité de cette thèse réside dans l’application d’un paradigme de combustion 0D, issu d’une approche 3D élaborée chez IFP Energies nouvelles et appliquée avec succès aux moteurs alternatifs ainsi qu’à des turbines à gaz. Le sous-modèle intègre le formalisme de flamme cohérente qui distingue une zone de gaz frais d’une zone de gaz brûlés. Les deux zones sont séparées par une flamme turbulente. Le sous-modèle de tube à flamme décrit la flamme grâce à une synthèse issue de résultats de calculs CFD 3D validés par des expériences. En effet, des résultats de calculs LES d’un brûleur expérimental monophasique ont étés analysés pour caractériser la combustion turbulente prémélangée dans un brûleur à tourbilloneur. Enfin, un secteur de brûleur réel de turbomoteur a été étudié à l’aide de simulations CFD afin d’évaluer la pertinence du modèle de tube à flamme 0D/1D et de guider la modélisation permettant de compléter la nouvelle approche de simulation système des turbines à gaz. / This work investigates a unique 0D/1D physical approach for gas turbine combustor modelling. It accounts for fuel evaporation, turbulence, combustion, and allows to represent dilution stages. Detailed pollutants formation models can also be added. The chosen formalism, based on the Bond Graph theory approach, allows to describe systems organised in a series of submodel components such as a series of open volumes forming a flame tube, or a combustor coupled to a compressor and turbine but they can also be combined with control and regulation devices in order to represent a complete rotorcraft. The essence of the PhD strategy is the application of a 0D combustion paradigm, obtained at IFP Energies nouvelles by formal reduction of 3D approaches for gas turbines. More in details, a new combustion model was developed integrating the Coherent Flame Model (CFM) formalism which allows to distinguish between fresh gases and burned gases separating them with a turbulent flame. The flame tube submodel features a physical description of the flame thanks to thorough understanding given by 3D CFD simulation results validated against experimental measurements. More specifically, LES results corresponding to a single phase test rig were analysed in order to characterise premixed turbulent combustion in a swirl burner. Finally, a real turboshaft combustor sector case was studied by means of CFD simulations to investigate the relevance of the 0D/1D flame tube model and to determine modelling strategies for the completion of the new gas turbine system simulation approach.

A indústria da cana-de-açúcar brasileira é reconhecida por sua competitividade e baixos custos de produção de etanol e açúcar. O lançamento do veículo bicombustível em 2003 acelerou o crescimento da indústria nesta década. Apesar desse crescimento, a indústria da cana-de-açúcar passa por momentos de incerteza devido a falta de investimentos, aumento dos custos de produção e ausência de políticas públicas que regulem o uso do etanol como combustível. Esta tese explora a dinâmica da indústria da cana-de-açúcar. Um modelo de Dinâmica de Sistemas é desenvolvido para explorar o comportamento da indústria por uma perspectiva endógena. Sem pressupor equilíbrio, o modelo oferece uma representação geral das principais ligações entre os setores da indústria. A estrutura causal do sistema é largamente explorada, gerando insights sobre as razões endógenas do comportamento do sistema real. O comportamento do modelo mostra boa agregação aos dados reais, aumentando a confiança da sua estrutura. É conduzida uma análise de política e o resultado emergente do sistema gera interessantes insights sobre o comportamento do modelo. Os achados do trabalho incluem: - Comportamento inesperado do sistema; - Elevado grau de acoplamento entre a indústria do açúcar e do etanol; - A baixa elasticidade-preço da demanda no mercado internacional de açúcar, e moderada no mercado nacional; - Reação endógena à implementação de políticas; - A indústria é pouco responsiva ao crescimento da demanda, quando isso exige aquisição de nova capacidade produtiva; e - Contribuição sobre o conhecimento existente da indústria. A tese é concluída com sugestões para trabalhos futuros, que conectam o modelo com várias áreas de conhecimento onde podem ser esperados problemas no médio ou longo prazo; esses problemas são: - Redução na emissão de CO2; - Efeitos do uso da terra; - Efeitos da entrada de novos combustíveis no mercado; e - Inclusão da bioenergia, gerada a partir do bagaço de cana, que altera a estrutura de custos da indústria. / The sugarcane industry in Brazil is recognized for its competitiveness and low production cost of both ethanol and sugar. The flex-fuel technology, launched in 2003, boosted the industry growth in the last decade. Despite this growth, sugarcane industry is undergoing a period of uncertainty due to a lack of investments, raising production costs, and a lack of policies concerning the ethanol regulation. This dissertation explores the dynamic of the sugarcane industry. A system dynamics model is developed to explore the industry behavior from an endogenous perspective. The model provides a general disequilibrium representation of the major linkages between the main sectors of the industry. The causal structure of the system is highly explored generating insights on the endogenous reasons of the industry behavior. Model behavior shows a good fit with real world data increasing the confidence on model structure. A single policy analysis is carried out and its emerging results generate insights on the endogenous reasons of system behavior. Findings on these results include: h Surprising behavior of the model; h The high degree of coupling between the sugar and ethanol industries; h The very low price-elasticity of demand on the international sugar market, and a moderate price-elasticity of demand on the national sugar market; h Endogenous policy reaction; h Low responsivity of industry to an increase demand, due to high delays in capacity acquisition; h Delays in capacity acquisition generating dynamics; h Contribution to existing knowledge on the system. The dissertation finishes with suggestions for future works linking the model with several areas of knowledge with potential problems in the middle or long term for the industry; these problems are: h Reduction in CO2 emissions; h Land-use effects; h Effects of new fuels insertion in the market; and h Inclusion of power generation using sugarcane bagasse, which changes the industry cost structure.

The industry of our country has turned to the Hi-Tech industry gradually, the competition among the same industry is fiercer and fiercer, different properties of industries move towards the road of the heterogeneous alliance gradually too. Under this rival environment, without doing out of the common being, the ability that will lose key competition soon withdraws , the management of making the respect is an indispensable ring too, because management is not good, even more advanced technology may be unable to consolidate enterprises in the position of the environment now. Service Quality Management (SQM) is a kind of management idea that can be suitable for various trades, the service pointed herein refers to various functions that all industries offer in general. This research will canvass the concept of Service Quality Management, use in our country the semiconductor assembly factory of Manufacturing Execution System (MES), embed Preventive Maintenance and Productivity Maintenance Systematic association, in order to reach the different property systems, carry on discussion and analysis. The systems of two kinds of different ways, build the system which forms different management styles by way of simulation, and use Arena simulation software to simulation and analysis under different situation, and canvass its own benefits. The results can be regarded as the manufacturing industry reference basis while construct a Manufacturing Execution System into or revised.