In the increasingly fierce international competition today, short product life cycle has led to lead time compression and narrow profit margins. Rapid respond to customers has become the key to survival of modern enterprises. Many large corporations in Taiwan have implemented the Toyota¡¦s just-in-time (JIT) production planning approach to reduce inventory to a minimum level, keeping on hand only the amount needed in production until the next order arrives. However, most of those companies have often overlooked that the basic principal of just-in-time replenishment model is the raw materials and other purchased items should be delivered steadily by the supplier when they are needed, and meanwhile those materials from suppliers require no inspection. Nevertheless, it is very difficult to achieve those objectives of JIT Production, especially in an increased market demand. Once some of the suppliers can not meet the delivery time of raw materials and quality is also affected, it would derive lots of problems. This study is aimed to JIT replenishment models on examining firms¡¦ inventory issues. Based on the result of the analysis, it would be the reference to build up the model of quality-oriented embedding collaborative replenishment mechanism for enterprises to improve their JIT replenishment operations. This model, quality-oriented embedding collaborative replenishment model, could assist business in measuring the accurate and precise delivery time and ensuring product quality from suppliers. The research is on the basis of Taiwan optoelectronic industry to investigate the companies of the TFT-LCD panel, and the supply chains of the industry. In analyzing the main TFT-LCD panel providers, the paper will probe into TFT-LCD firms to implement the inventory management system by building the quality-oriented embedding collaborative replenishment mechanism to improve the reaction capacity of businesses, to reduce the risk of raw material quality issues, and to respond to the market rapid change. The study exerts simulation software to conduct simulation and improvement of such models, then according to the simulation results to utilize them as a reference to implementation of quality-oriented embedding collaborative replenishment model into the future operation.

The development of statistical process control has been for a long time and can be turned up in many manufacturing environments. However, statistical process control applications in process control generally limited to use the control chart applications, the deepening capacity for control charts such as process capability control, variation detection and evaluation, are rarely described so often so that statistical process control techniques is relegated. Meanwhile, statistical process control can detect the production process of the variations, but it can¡¦t integrate the production resource capacity. Although the process control of manufacturing processes can achieve real-time control of effects, but the resources of the production process appeared to be quite inadequate in response to future demand forecast and capacity analysis. Therefore, this study combined with statistical process control system simulation technology for innovative management. Through the process observation and sample collection, we can use simulation technology to propose the process feasibility and applicability in resource constraint and resource allocation for considering the variation of the statistical process control, and use the quality improvement tools and causal feedback map, the system dynamics tools, in the resource dynamic ability for decision-making management. The research result appears: 1¡BBased on the effective input parameters of simulation model , it can effectively simulate the actual production processes and produce an effective output. 2¡BThrough the appropriate statistical data validation, it can improve the sample reliability as an important reference to system simulation methods. 3¡BUsing the simulation technology, we can monitor the online process control, production resources allocation and capacity prediction.

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The complexity among embedded systems has increased dramatically in recent years. During the same time has the capacity of the hardware grown to astonishing levels. These factors have contributed to that software has taken a leading role and time-consuming role in embedded system development.Compared with regular software development, embedded development is often more restrained by factors such as hardware performance and testing capability. A solution to some of these problem has been proposed and that is a concept called virtual platforms. By emulating the hardware in a software environment, it is possible to avoid some of the problems associated with embedded software development. For example is it possible to execute a system faster than in reality and to provide a more controllable testing environment. This thesis presents a case study of an application specific virtual platform. The platform is based on already existing embedded system that is located in an industrial control system.  The virtual platform is able to execute unmodified application code at a speed twice of the real system, without causing any software faults. The simulation can also be simulated at even higher speed if some accuracy losses are regarded as acceptable.The thesis presents some tools and methods that can be used to model hardware on a functional level in an software environment. The thesis also investigates the accuracy of the virtual platform by comparing it with measurements from the physical system. In this case are the measurements mainly focused of the data transactions in a controller area network bus (CAN).

Commissioning of HVAC systems has potential for significant improvements in occupant satisfaction, comfort and energy consumption, but is very labour-intensive and expensive as practiced at this time. Previous investigators have capitalized on digital control systems' capability of logging and storing data and of interfacing with external computers for open loop control by developing methods of automated fault detection and diagnosis during normal operation. Some investigators have also considered the application of this technique in commissioning. This thesis investigates the possibility of utilizing first principles and empirical models of air-handling unit components to represent correct operation of the unit during commissioning. The models have parameters whose values can be determined from engineering design intent information contained in the construction drawings and other data available at commissioning time. Quasi-dynamic models are developed and tested. The models are tested against design intent information and also against data from a real system operating without known faults. The results show the models agree well with the measured data except for some false positive indications, particularly in the damper and fan models, during transients. A procedure for estimating uncertainty in the instrumentation and the models is developed. The models are also tested against artificial faults and are able to detect all of the faults. Methods of diagnosing the faults are discussed.

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.

TSP (or Telecommunication Server Platform) is a scalable, high availability cluster operating system developed by Ericsson for use in the telecommunications industry. This thesis describes an attempt to simulate a TSP cluster in the full system simulator Simics, and talks about some of the possibilities offered by such a setup and full system simulation in general. This attempt to simulate TSP was unsuccessful in completely booting the cluster in Simics, but some of the experiences and problems encountered are described. A proposed development environment for working with TSP in Simics is also presented, along with scripts that were created during this thesis to alleviate the working process. / TSP (eller Telecommunication Server Platform) är en skalbar, högt tillgängligt kluster-operativsystem utvecklat av Ericsson för användning inom telekommunikationsindustrin. Den här rapporten beskriver ett försök att simulera TSP-kluster i full-system simulatorn Simics, och beskriver en del av de möjligheter med detta och full-system simulering i allmänhet. Det här försöket att simulera TSP lyckades inte att fullständigt boota klustret i Simics, men några av de erfarenheter och problem som stöttes på är beskrivna. En föreslagen utvecklingsmiljö presenteras också, tillsammans med script som skapades under det här arbetet för att underlätta arbetet. / Olle Eriksson, Contact info at www.olle-eriksson.com Emil Erlandsson, Contact info at www.buglix.org

Two new methods for the simulation of gas turbine fuel systems, one based on an inter-component volume (ICV) method, and the other based on the iterative Newton Raphson (NR) method, have been developed in this study. They are able to simulate the performance behaviour of each of the hydraulic components such as pumps, valves, metering unit of a fuel system, using physics-based models, which potentially offer more accurate results compared with those using transfer functions. A transient performance simulation system has been set up for gas turbine engines based on an inter-component volume (ICV). A proportional- integral (PI) control strategy is used for the simulation of engine control systems. An integrated engine and its control and hydraulic fuel systems has been set up to investigate their coupling effect during engine transient processes. The developed simulation methods and the systems have been applied to a model turbojet and a model turboshaft gas turbine engine to demonstrate the effectiveness of both two methods. The comparison between the results of engines with and without the ICV method simulated fuel system models shows that the delay of the engine transient response due to the inclusion of the fuel system components and introduced inter-component volumes is noticeable, although relatively small. The comparison of two developed methods applied to engine fuel system simulation demonstrate that both methods introduce delay effect to the engine transient response but the NR method is ahead than the ICV method due to the omission of inter-component volumes on engine fuel system simulation. The developed simulation methods are generic and can be applied to the performance simulation of any other gas turbines and their control and fuel systems. A sensitivity analysis of fuel system key parameters that may affect the engine transient behaviours has also been achieved and represented in this thesis. Three sets of fuel system key parameters have been introduced to investigate their sensitivities, which are, the volumes introduced for ICV method applied to fuel system simulation; the time constants introduced into those first order lags tosimulate the valve movements delay and fuel spray delay effect; and the fuel system key performance and structural parameters.

The Organic Rankine Cycle (ORC) may be the superior cycle for power generation using low temperature and low power heat sources due to the utilization of high molecular mass fluids with low boiling points. They are flexible, simple, easy to operate and maintain, and offer many possible areas of applications including waste heat recovery and power generation from biomass, geothermal and even solar energy. Therefore, they may prove to be of significant importance in reducing global greenhouse gas emission and in the mitigation of climate change. In this thesis the technical feasibility and economic profitability of implementing an ORC in a district heating boiler station is investigated. A model of ORC connected to the hot water circuit of one of the biomass boilers of the boiler station is simulated. The achieved evaporation temperature is estimated to 135 degrees C and the condensation temperature is found to vary in the range of about 70-100 degrees C. The results show that it is both possible and profitable to implement an ORC in the studied boiler station. A maximum net present value of 2.3 MSEK is achieved for a 400 kW system and a maximum internal rate of return of 8.5%, equivalent to a payback period of 9.5 years, is achieved for a 300 kW system. Furthermore, the investment is found to be most sensitive to changes in the electricity price, net electric efficiency and capital expenditure cost.

La présence de contraintes de plus en plus strictes sur les émissions de polluants on poussé les contruteurs vers l'injection directe essence (IDE), afin d'améliorer les performances et réduire la consommation de carburant et les émissions des moteurs à combustion interne. Par conséquent, de nouveaux défis sont introduits en termes d'optimisation de la combustion, en raison d'une plus complexe phénomenologie tandis que les modéles système demande des paramètres de calibration supplémentaires.Cette thèse présente le développement et la validation d'un modèle zéro-dimensionnel (0D) de combustion en IDE pour application en simulation système. Le modèle proposé détaille la physique de l'atomisation, et évaporation des gouttes, de la préparation du mélange air/carburant, de la propagation de flamme dans un mélange non-homogène ainsi que l'intéraction entre ces phénomènes.La phase liquide est discretisés en paquets groupant des gouttes de la même taille.Un modèle d'atomisation empirique basé sur la vitesse d'injection, les propriétés du carburant et les conditions thermodynamiques fournit les diamètres initiaux. Un modèle Lagrangien détaillant une dynamique de trainée/inértie, échange thermique et convection forcée décrit la pénétration liquide et l'evaporation des paquets. La formation du mélange air/carburant est décrite avec une PDF qui discretise la charge en un mécanisme de classes intéragissant les unes avec les autres et avec les paquets de gouttes. La propagation de flamme prend en compte les effets de l'hétérogéneité du mélange sur la vitesse de flamme et la formation des polluants.Le modèle proposé a été implémenté dans la plateforme Simcenter Amesim, dédiée á la modélisation de systémes multi-physiques, et intégrée dans le modèle de combustion essence CFM1D, de la librairie IFP-Engine.Des approche de modélisation de l'evaporation de carburant, de la dynamique de spray et de la formation du mélange, inspirés de la literature sur les moteurs Diesel, ont été adaptés aux conditions IDE.Le modèle a initialement été validé sur des mesures et des simulations RANS 3D réalisées avec le code IFP-C3D, d'une bombe d'injection à volume constant.Un vortex de tumble, dans un premier temps, et des variations rapides du voulume de la chambre ensuite, ont été ajoutés aux expériments numériques afin d'évaluer la réponse du modèle à l'aérodynamique dans la chambre de combustion et à des conditions thermodynamiques variables, en termes d'évaporation, développement du spray et distribution de la richesse. Des simulations d'injections dans un moteur entraîné,dont les résultats ont été comparés avec des mesures et des calculs CDF,complètent la validation du modèle avec à la fois des conditions thermodynamiques variable et de l'aérodynamique. / Future constraints on pollutant emissions pushed car manufacturers towards gasoline direct injection (GDI) technologies to improve engine performances and reduce fuel consumption and emissions. New challenges are then introduced in terms of combustion optimization due to a more complex phenomenology while system models require additional calibration parameters.This PhD work presents the development and validation of a Zero-Dimensional (0D) model of GDI combustion for system simulation. The proposed model focuses on physics of atomization and drop evaporation, fuel/air mixing, flame propagation in heterogeneous charge and mutual interaction between these phenomena.The liquid phase is discretized in parcels grouping drops of the same size. An empirical atomization model based on injection velocity, fuel characteristics and thermodynamic conditions provides initial diameters. A Lagrangian model including drag-inertia dynamics, heat-up and forced convection describes drop parcel penetration and evaporation. Fuel / air mixing is described using a discrete Probability Density Function (PDF) approach, based on constant-mixture-fraction classes interacting with each other and with the drop parcels. Flame propagation takes into account mixture heterogeneity effects on flame speed and pollutant production is modelled.The model was implemented in the Simcenter Amesim platform for multi-physical modelling and integrated in a generic Spark Ignition (SI) combustion chamber submodel, CFM1D, from the IFP-Engine library.Fuel evaporation, spray dynamics and mixture formation modelling approaches, inspired by literature on Diesel engines, were adapted to GDI operating conditions. The model was first validated on a constant-volume vessel with quiescent gas in different thermodynamic conditions by means of experiments and 3D RANS CFD simulations performed with IFP-C3D. A tumble vortex in a constant volume vessel, in a first time, and rapid variations of the vessel volume, in a second time, were then added to the numerical experiment in order to test the model response to in-cylinder flow aerodynamics and variable thermodynamic conditions, respectively, in terms of fuel evaporation, spray development and fuel/air mixing and equivalence ratio distribution. Computations of fuel injections in a motored engine complete the model validation campaign in variable thermodynamic conditions and with realistic aerodynamics and the results were compared to both experiments and CFD computations.