Conceptual modeling is considered to be essential in simulation development activities. However, there are only a few research studies on how to develop conceptual models. One of the important and comprehensive approaches is the methodology developed under the leadership of METU Modeling and Simulation Center (MODSIMMER) for Turkish Armed Forces. The project suggests a methodology to develop mission space conceptual models (GUKAM), and provides a Conceptual Model Development Tool for C4ISR M&amp / S activities, which is named as KAMA-C4ISRMOS. KAMA methodology is developed to utilize conceptual models in requirements collection and analysis activities. Two improvement opportunities observed in KAMA approach are that, there are no methodologies defined to develop simulation space conceptual models / and although most approaches emphasize the importance of conceptual model to be used in design activities, no explanations are provided on how to do it. This thesis aims to suggest an extended KAMA methodology that, besides original KAMA properties, provides a method to develop simulation space conceptual model, and provides a guide to use conceptual model to develop design. To evaluate the suggested methodology, a case study is conducted on a synthetic environment project. In this way, implementation of the methodology on another simulation domain is depicted. Developed mission space and simulation space conceptual models and design artifacts are evaluated, and the effects of conceptual models on simulation development life cycle are discussed.

This diploma thesis deals with the design of a virtual prototype of a luminaire. Using suitable software tools, a luminaire optics is created and optimised. Luminaire is simulated in the interior, and lighting parameters are evaluated. Finally a suitable design is created.

The aim of this Thesis is giving information about the network simulating system OMNeT++ and its extension INET framework and explore possible solution to implement missing protocol RIP. OMNeT++ is a discrete-event simulation environment. Source code is available and free for teaching and research purposes. Its primary application area is the simulation of communication networks, but because of its generic and flexible architecture, is successfully used in other areas like the simulation of complex IT systems, queueing networks or hardware architectures as well. The first part of Thesis decribes RIP protocol operations and conception of OMNeT++. At the second part of Thesis the implementation design and discussion of created modules and component is presented here. The final part of the Thesis was creating the laboratory problem on the basis experience gained. Implementation is realized in C++ programming language.

In recent years, advances in small unmanned aerial vehicle (UAV) technology have transformed the use cases of these aircraft from hobby flying to industrial and business applications. These maneuverable, easily deployed tools can be retrofitted with a myriad of sensors and equipment, which make them suitable to perform a variety of specialized tasks. With increasing UAV capabilities, the function of small UAVs can be extended from pure monitoring or surveillance to the dual objective of monitoring an environment for events and addressing the events in some way. This thesis seeks to explore a subdomain of the dual objective problem described, referred to in this thesis as the multi-UAV persistent search and retrieval task with stochastic target appearance (PSR-STA), in which UAVs continuously search an area over a long period of time for targets of interest, which appear according to a probabilistic model, to retrieve and deliver them to a collector location. The advent of high-speed computers and agent-based modeling theory enable the simulation of multi-UAV PSR-STA. However, it can be complicated to combine parts of multi-UAV PSR-STA such as motion models and multi-UAV coordination into one integrated system, and even after they are combined successfully, it is difficult to analyze the system except with simple comparison tools. This thesis 1) proposes a framework that builds a foundation for understanding how to simulate and analyze multi-UAV PSR-STA through prescribing important design decisions and methods for simulation and 2) identifies metrics, analysis tools, and trends related to overall system effectiveness for multi-UAV PSR-STA. A case study of multi-UAV park cleanup is implemented where many simulations with input parameters chosen by a latin hypercube design of experiments are examined, algorithms for choosing the locations of collectors and charging stations based on probabilistic information are proposed, and the differences in effectiveness between four coverage search patterns are analyzed. Measures are highlighted that provide insight into performance variability over time and space. Line charts and the discrete Fourier transform are used to understand temporal patterns inherent in the data. Principal component analysis is used to analyze relevant spatial patterns in effectiveness, and a random forest surrogate model with a profiler is used to explore the non-linear influence of input parameters on the spatial patterns. The trellis chart or figure of figures method is presented for visualizing spatial and temporal data across many simulations. A second set of experiments based on the park cleanup case study are performed and examined to verify the benefits of these methods.

Master’s thesis includes knowledges about mobility support in IPv4 networks and studies abilities for mobility support in IPv6 networks. Describes protocols for mobility support, their functions and topologies like MIPv6 (RFC 3775), FMIPv6 (RFC 5568), HMIPv6 (RFC 5380) and F-HMIPv6. The thesis contains a design of the simulation MIPv6 in the OPNET Modeler program and the measured results are explained. There are analysis of source code for mobility support in MIPv6 too, which were used for design a new protocol according to FMIPv6 in the OPNET. The following parts of the proposal have been successfully resolved. The link-layer events detection, which triggers FMIPv6 protocol and implementation of two new types of messages, RtSolPr and PrRtAdv. Knowledges from this thesis could be used for next development of FMIPv6 in the OPNET. But could be used for generaly development new protocols working at network-layer too.

This study evaluates a number of software reinspection decision policies for software code inspections with the aim of revealing their effects regarding cost, schedule and quality related objectives of a software project. Software inspection is an effective defect removal technique for software projects. After the initial inspection, a reinspection may be performed for decreasing the number of remaining defects further. Although, various reinspection decision methods are proposed in the literature, no study provides information on the results of employing different methods. In order to obtain insight about this unaddressed issue, this study compares the reinspection decision policies by finding out and analyzing their performance with respect to designated measures and preference profiles for cost, schedule, and quality perspectives in the context of a typical Software Capability Maturity Model Level 3 software organization. For this purpose, a Monte Carlo simulation model, which represents the process comprising initial code inspection, reinspection, testing and field use activities, is employed in the study together with the experiment designed in order to consider different circumstances under which the mentioned process operates. The study recommends concluding the reinspection decision by comparing inspection effectiveness measure for major defects with respect to a moderately high threshold value (i.e. 75%). The study also reveals that applying default decisions of &lsquo / Never Reinspect&rsquo / and &lsquo / Always Reinspect&rsquo / do not exhibit the most appropriate outcomes regarding cost, schedule, and quality. Additionally, the study presents suggestions for further improving the cost, schedule, and quality of the software based on the analysis of the experiment factors.

Orientador: Jose Vicente Hallak D'Angelo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-11T14:06:54Z (GMT). No. of bitstreams: 1 Cipolato_Liza_M.pdf: 1029854 bytes, checksum: e29def5b437d5ad6a00d8fc677c63bf5 (MD5) Previous issue date: 2008 / Resumo: O comércio de gás natural liquefeito apresenta um crescente interesse por parte tanto de países exportadores como dependentes desta fonte energética. Apesar de o transporte por gasoduto ser muito menos suscetível a perdas, ele se torna inviável a longas distâncias ou a demandas variáveis. A liquefação do gás natural também proporciona o armazenamento desta fonte energética numa forma estável e de alto potencial energético,evidenciando o caráter estratégico do processo. Desde a década de 60 a tecnologia para liquefação do gás natural é utilizada, porém, apenas há alguns anos os países iniciaram o comércio desta fonte energética em larga escala e isto acarretará um aumento mundial tanto no número de terminais exportadores (plantas de liquefação) quanto importadores (terminais de regaseificação). O processo de liquefação do gás natural ocorre através de uma sequência de ciclos termodinâmicos de refrigeração, e estes, por sua vez, precisam trabalhar de forma otimizada para reduzir perdas. A análise exergética é uma ferramenta muito útil para avaliar estas perdas e pode ser essencial na instalação de uma nova planta ou melhoria de uma já existente. O presente trabalho realizou uma análise exergética de um ciclo de refrigeração utilizado para a liquefação de gás natural, o qual é do tipo multiestágio em cascata, padrão utilizado atualmente, sendo o mais conhecido e difundido entre as indústrias da área. Primeiramente, o processo foi simulado em software comercial Hysys (versão 3.2 da Aspen Technology). O resultado obtido da simulação foi validado através de comparação com dados da literatura, mostrando-se adequado. Em seguida, a simulação foi testada em diferentes condições operacionais, seguindo um planejamento fatorial completo, o qual teve como objetivo verificar a influência da variação das pressões de seis pontos específicos do ciclo sobre a variável resposta, que é a taxa de exergia total destruída no processo, visando sua minimização. Os resultados obtidos levaram a uma nova condição de operação para o ciclo de refrigeração com redução de aproximadamente 48% da taxa de exergia destruída com relação aos dados do caso obtido da literatura. Tal resultado evidencia o potencial da metodologia termodinâmica utilizada, demonstrando sua aplicação em estudos de melhoria do desempenho de ciclos de refrigeração para a indústria de liquefação de gás natural / Abstract: The liquefied natural gas trade shows a growing interest either from countries which are exporters or countries which depend on this kind of energetic source. Although gas pipelines are less susceptible of transportation losses, they become impracticable when distances are too long or when demands are highly variable. The liquefaction of natural gas also enables its storage in a stable way, in which energetic potential is high, expressing the strategic purpose of the process. Since the 1960 decade natural gas liquefying technology is been used, but only a few years ago countries have started the trade of this kind of energetic source on a large scale. Consequently, the number of exporter terminals (liquefaction industries) and importer terminals (regasification plants) will increase worldwide. The natural gas liquefaction process is based on a sequence of refrigeration thermodynamics cycles, which need to work in an optimized way in order to reduce losses. The exergy analysis is a very useful tool to evaluate these losses and can be crucial in a new plant installation or in a current one improvement. This dissertation performed an exergy analysis of a multistage cascade refrigeration cycle applied in natural gas liquefaction. The multistage cascade cycle is currently the standard type, being the most known and diffused among industries. Firstly, the process was simulated in commercial software Hysys (version 3.2 of Aspen Technology). The result obtained from the simulation was validated by comparison with the literature data and showed a very adequate similarity. After that, the simulation was checked in different operational conditions, according to the complete factorial design of experiments. The design of experiments¿ objective was to verify the pressure influence of six specific points of the cycle over the response variable, which is the rate of total exergy destroyed in the cycle, in order to reach its minimal value. The results showed a new operational condition to the refrigeration cycle, in which the destroyed exergy rate was reduced by approximately 48% in comparison with literature data. This result provides evidence of the high potential of the thermodynamic tool used, showing its application in studies of performance improvements for refrigeration cycles in industries of natural gas liquefaction / Mestrado / Sistemas de Processos Quimicos e Informatica / Mestre em Engenharia Química

This thesis deals with the structural design of mass flowmeter based on the principle of the Coriolis force. The introduction explains how the Coriolis flowmeter operates, what types of flowmeters are currently being produced and what are the important parameters. There are appointed some of the principles that must be followed to the meter working correctly. It contains a proposal design of flowmeter for pipes DN80 and. Includes drawings for this design.

Coal-fired power plants are the largest anthropogenic point sources of CO2 emissions worldwide. About 40% of the world's electricity comes from coal. Approximately 49% of the US electricity in 2008 and 23% of the total electricity generation of Canada in 2000 came from coal-fired power plant (World Coal Association, and Statistic Canada). It is likely that in the near future there might be some form of CO2 regulation. Therefore, it is highly probable that CO2 capture will need to be implemented at many US and Canadian coal fired power plants at some point. Several technologies are available for CO2 capture from coal-fired power plants. One option is to separate CO2 from the combustion products using conventional approach such as chemical absorption/stripping with amine solvents, which is commercially available. Another potential alternative, membrane gas separation, involves no moving parts, is compact and modular with a small footprint, is gaining more and more attention. Both technologies can be retrofitted to existing power plants, but they demands significant energy requirement to capture, purify and compress the CO2 for transporting to the sequestration sites. This thesis is a techno-economical evaluation of the two approaches mentioned above along with another approach known as hybrid. This evaluation is based on the recent advancement in membrane materials and properties, and the adoption of systemic design procedures and optimization approach with the help of a commercial process simulator. Comparison of the process performance is developed in AspenPlus process simulation environment with a detailed multicomponent gas separation membrane model, and several rigorous rate-based absorption/stripping models. Fifteen various single and multi-stage membrane process configurations with or without recycle streams are examined through simulation and design study for industrial scale post-combustion CO2 capture. It is found that only two process configurations are capable to satisfy the process specifications i.e., 85% CO2 recovery and 98% CO2 purity for EOR. The power and membrane area requirement can be saved by up to 13% and 8% respectively by the optimizing the base design. A post-optimality sensitivity analysis reveals that any changes in any of the factors such as feed flow rate, feed concentration (CO2), permeate vacuum and compression condition have great impact on plant performance especially on power consumption and product recovery. Two different absorption/stripping process configurations (conventional and Fluor concept) with monoethanolamine (30 wt% MEA) solvent were simulated and designed using same design basis as above with tray columns. Both the rate-based and the equilibrium-stage based modeling approaches were adopted. Two kinetic models for modeling reactive absorption/stripping reactions of CO2 with aqueous MEA solution were evaluated. Depending on the options to account for mass transfer, the chemical reactions in the liquid film/phase, film resistance and film non-ideality, eight different absorber/stripper models were categorized and investigated. From a parametric design study, the optimum CO2 lean solvent loading was determined with respect to minimum reboiler energy requirement by varying the lean solvent flow rate in a closed-loop simulation environment for each model. It was realized that the success of modeling CO2 capture with MEA depends upon how the film discretization is carried out. It revealed that most of the CO2 was reacted in the film not in the bulk liquid. This insight could not be recognized with the traditional equilibrium-stage modeling. It was found that the optimum/or minimum lean solvent loading ranges from 0.29 to 0.40 and the reboiler energy ranges from 3.3 to 5.1 (GJ/ton captured CO2) depending on the model considered. Between the two process alternatives, the Fluor concept process performs well in terms of plant operating (i.e., 8.5% less energy) and capital cost (i.e., 50% less number of strippers). The potentiality of hybrid processes which combines membrane permeation and conventional gas absorption/stripping using MEA were also examined for post-combustion CO2 capture in AspenPlus®. It was found that the hybrid process may not be a promising alternative for post-combustion CO2 capture in terms of energy requirement for capture and compression. On the other hand, a stand-alone membrane gas separation process showed the lowest energy demand for CO2 capture and compression, and could save up to 15 to 35% energy compare to the MEA capture process depending on the absorption/stripping model used.

Coal-fired power plants are the largest anthropogenic point sources of CO2 emissions worldwide. About 40% of the world's electricity comes from coal. Approximately 49% of the US electricity in 2008 and 23% of the total electricity generation of Canada in 2000 came from coal-fired power plant (World Coal Association, and Statistic Canada). It is likely that in the near future there might be some form of CO2 regulation. Therefore, it is highly probable that CO2 capture will need to be implemented at many US and Canadian coal fired power plants at some point. Several technologies are available for CO2 capture from coal-fired power plants. One option is to separate CO2 from the combustion products using conventional approach such as chemical absorption/stripping with amine solvents, which is commercially available. Another potential alternative, membrane gas separation, involves no moving parts, is compact and modular with a small footprint, is gaining more and more attention. Both technologies can be retrofitted to existing power plants, but they demands significant energy requirement to capture, purify and compress the CO2 for transporting to the sequestration sites. This thesis is a techno-economical evaluation of the two approaches mentioned above along with another approach known as hybrid. This evaluation is based on the recent advancement in membrane materials and properties, and the adoption of systemic design procedures and optimization approach with the help of a commercial process simulator. Comparison of the process performance is developed in AspenPlus process simulation environment with a detailed multicomponent gas separation membrane model, and several rigorous rate-based absorption/stripping models. Fifteen various single and multi-stage membrane process configurations with or without recycle streams are examined through simulation and design study for industrial scale post-combustion CO2 capture. It is found that only two process configurations are capable to satisfy the process specifications i.e., 85% CO2 recovery and 98% CO2 purity for EOR. The power and membrane area requirement can be saved by up to 13% and 8% respectively by the optimizing the base design. A post-optimality sensitivity analysis reveals that any changes in any of the factors such as feed flow rate, feed concentration (CO2), permeate vacuum and compression condition have great impact on plant performance especially on power consumption and product recovery. Two different absorption/stripping process configurations (conventional and Fluor concept) with monoethanolamine (30 wt% MEA) solvent were simulated and designed using same design basis as above with tray columns. Both the rate-based and the equilibrium-stage based modeling approaches were adopted. Two kinetic models for modeling reactive absorption/stripping reactions of CO2 with aqueous MEA solution were evaluated. Depending on the options to account for mass transfer, the chemical reactions in the liquid film/phase, film resistance and film non-ideality, eight different absorber/stripper models were categorized and investigated. From a parametric design study, the optimum CO2 lean solvent loading was determined with respect to minimum reboiler energy requirement by varying the lean solvent flow rate in a closed-loop simulation environment for each model. It was realized that the success of modeling CO2 capture with MEA depends upon how the film discretization is carried out. It revealed that most of the CO2 was reacted in the film not in the bulk liquid. This insight could not be recognized with the traditional equilibrium-stage modeling. It was found that the optimum/or minimum lean solvent loading ranges from 0.29 to 0.40 and the reboiler energy ranges from 3.3 to 5.1 (GJ/ton captured CO2) depending on the model considered. Between the two process alternatives, the Fluor concept process performs well in terms of plant operating (i.e., 8.5% less energy) and capital cost (i.e., 50% less number of strippers). The potentiality of hybrid processes which combines membrane permeation and conventional gas absorption/stripping using MEA were also examined for post-combustion CO2 capture in AspenPlus®. It was found that the hybrid process may not be a promising alternative for post-combustion CO2 capture in terms of energy requirement for capture and compression. On the other hand, a stand-alone membrane gas separation process showed the lowest energy demand for CO2 capture and compression, and could save up to 15 to 35% energy compare to the MEA capture process depending on the absorption/stripping model used.