No description available.

"Building design and site features have an influence on helping or hindering fire fighting operations. Traditional studies relating to building performance evaluation for fire department operations do not address the influence of building site and architectural design on local fire department suppression techniques. These studies also do not relate fire fighting analysis to anticipated fire size. The goal of this dissertation is to develop an analytical procedure by which the size of a specified design fire can be predicted for the time at which fire fighting attack water application is likely to occur. The delays encountered due to building configuration and specified design fire conditions are incorporated in the analysis. Discrete Event Simulation is used to compute time durations for fire fighting operations. The results of this dissertation may be used as a stand alone technical analysis for any office building or as a part of a more complete building performance evaluation. "

No description available.

This work describes the research conducted in the quest for designing better software for discrete-event system (DES) control. The think-aloud data from an exploratory observational study of solving DES control problems contributed to the formulation of a list of recommendations on how to design and improve DES software. These observations, together with other relevant research, led to the proposal of a novel approach to DES problem solving, namely, the template design methodology. This methodology does not require the introduction of new control theory; it is rather an reinterpretation of the existing modelling framework. Software supporting this methodology was implemented and subsequently evaluated using twelve subjects. Significant improvements in the speed of problem solving as well as positive evaluations by the subjects were observed. The usability data do not show any drawbacks to applying the methodology. / Thesis (Ph.D, Computing) -- Queen's University, 2009-08-21 17:11:14.991

No description available.

The fierce competition among the manufacturers all over the world as a result of globalisation and the dynamic atmosphere of the market has brought a new era to the production world. Shorter lead times, faster takt-times, variety of demand and products by customers, optimized inventory level, new rules and regulations legislated by governments and organizations plus efficiency of the supply chain are examples of challenges which urge companies to seek for any feasible tool which help can help to overcome the upcoming complex problems. Recent advancements in the IT world have caused emergence of contemporary methods and tools for companies to use when confronting intricate situations to be able to handle such incidents and stay competitive in the market. Today, more companies realize the significance of change in their production system. Discrete-event simulation is one of the virtual tools used more and more recently in different areas. It is undoubtedly one of the most functional tools which could be used for different purposes in such as: System learning System prediction Scenario planning   The application scope of discrete-event simulation is both in micro and macro levels as it can be used in a partial study of a specific process in a manufacturing company for optimization or in a higher level, to help a company to analyze its strategic plans by simulating them ahead of time. In the current study it has been tried to investigate the application and implementation of discrete-event simulation in production. For reaching that goal, the project has been divided into two main parts; first of all a discrete event simulation has been conducted regarding a real-world potential problem. Later, by gaining the experience from the first part plus doing research around discrete simulation, it has been tried to develop a framework for industrial companies to ease the use of discrete-event simulation project process in a standardized manner. A future prospective of the current project could be the implementation of the results and provided framework on further real-world cases and explore more innovative uses of discrete-event tool in industry. Obviously, discrete-event could be a great decision-making or analysis tool for production development if being used in the proper context. / Simulering är en verktyg  som möjliggör system analys billigt och lätt. När man ska simulera ett system så bygger man en model baserad på verklighet med en viss nivå of abstraktion, beroende på syftet av simuleringen. De företag som har komplicerade processer kan använda simulering som en beslutsstöd verktyg. Genom simulering av ett komplicerat system så kan man uppnå olika saker: Lära om systemet Förutsäga e systemets beteende Scenarioplanering När det gäller simulering så krävs två olika saker som har varit grunden för detta projektet; förmågor inom systemet som kan simuleras, kunskaper inom simuleringsteknik. Båda faktorer spelar stor roll för att ett simuleringprojekt blir framgångsrik. Simulering har bred applikation och kan användas i olika områden exempelvis flyg simulatorer mm. Produktion är ett område där finns potential av att utnyttja simulering framförallt ’discrete-event’ typ av simulering som för det mesta passar produktionsanalyser på grund av diskret natur av produktions verksamhet. Genom att simulera produktion eller tillverkningssystem kan man i en virtuell miljö prova kapacitet, flödet och mm. Detta projekt har haft som mål att skapa ett standardiserat arbetssätt för användning av simulering (med fokus på DES) i produktionsutveckling. Projektet har genomförts inom Volvo CE, i Härdverket i Eskilstuna. Dessutom, det beskriver om utmaningar som dyker upp när man utför ett simuleringsprojekt genom en analys av det genomförde projektet. / <p>The project has been done with cooperation of Volvo Construction Equipments</p>

In a market environment that is subject to continuous changes, companies need to adapttheir production systems in order to maintain the competitive edge. Current literatureshows that with a successful production system design, higher levels of output, eciencyand quality can be achieved.However, designing a production system is done infrequently and therefore tends tolack experience. As a result, design decisions have to be made under uncertainty due toa lack of information, structure and knowledge. In fact, the success of a design process isdirectly linked to the level of uncertainty.The purpose of this thesis is to reduce uncertainty in production system design throughDiscrete Event Simulation before an assembly system is implemented. Therefore, a theoreticalstudy was carried out dening types and sources of uncertainty in productionsystem design. Parallel to the theoretical study, a case study in Volvo ConstructionEquipment Operations Hallsberg was conducted. Discrete Event Simulation was testedas a tool to reduce uncertainty in production system design.The analysis illustrates the observed sources of uncertainty in production systemdesign cover a process, organizational, corporate, market and cultural context.The relevant uncertainty types identied in the case study in Volvo ConstructionEquipment Operations Hallsberg were environmental, system, technical, structural,temporal, lack of knowledge and lack of information. The information providedby the Discrete Event Simulation in order to reduce uncertainty are in form ofKPIs, process structure and visualization. The provided information had a positiveimpact on the degree of technical uncertainties, the lack of knowledge and thelack of information. As a result, the level of uncertainty in the Volvo ConstructionEquipment Operations Hallsberg future line designing process was reduced.

Solar power systems are becoming increasingly popular due to the fact that solar power can offer time and money saving solutions for off-grid and grid-connected homes, cabins, and businesses with clean and affordable energy. However, there are still significant opportunities to reduce the cost of solar power systems by optimizing system design. This paper presents a methodology for evaluating the lifecycle labor costs of solar power systems. This methodology can help optimize system designs relative to cost. It can also support solar power system selection decisions based on a holistic lifecycle view. The methodology accomplishes this by first presenting a method to evaluate the modularity of competing systems, or design variants. It then describes a method of gathering data and modeling the systems so that it can be communicated to relevant stakeholders. Finally, it uses discrete event simulation to generate an estimate of relative lifecycle labor cost performance. Verification and validation of the methods described are presented through a case study of the MegaModule residential solar power system, designed by the team at GTRI. The paper concludes with a review of limitations and proposed future work.

Assembly lines are no longer systems designed to produce as much as possible at the lower cost. Nowadays several factors such as mass customization and variation in demand have led the manufacturers to consider the flexibility of the assembly systems as one of the most important facts to take into account when designing an assembly line. In this context, this study attempts to test a new paradigm of the workload balance, which is based on a dynamic allocation of the assembly operations. In order to test the hypothesis, a real assembly system of engines has been used as a base model to implement the new approach. The work developed, uses the simulation as a means to carry out the study, which has required the development of several simulation scenarios. The hypothesis has been studied from two different approaches; on one hand a total dynamic allocation of assembly operations, which was expected to cause a wide operational range of the stations. On the other hand, the second approach implements a flow control which aims to reduce the operational range and workload fluctuations. The results obtained show a significant improvement of the system performance in comparison with the current assembly line. It has been found that any improvement implemented in the system is directly reflected in the total performance of the line, regardless if the improvement is made in a system constraint. Moreover, the results have proven a better response of the system to changes in the frequency of models production.  Finally, based on the results, this study suggests several paths of future work in order to acquire the needed information to implement the hypothesis in the real world context. / Flexa project

Cycle-to-cycle control is a method for using feedback to improve product quality for processes that are inaccessible within a single processing cycle. This limitation stems from the impossibility or the prohibitively high cost of placing sensors and actuators that could facilitate control during, or within, the process cycle. Our previous work introduced cycle to cycle control for single input-single output systems, and here it is extended to multiple input-multiple output systems. Gain selection, stability, and process noise amplification results are developed and compared with those obtained by previous researchers, showing good agreement. The limitation of imperfect knowledge of the plant model is then imposed. This is consistent with manufacturing environments where the cost and number of tests to determine a valid process model is desired to be minimal. The implications of this limitation are modes of response that are hidden from the controller. Their effects on system performance and stability are discussed. / Singapore-MIT Alliance (SMA)