This simulation study considers a low-volume manufacturing system, which produces complex, customized electronics. Modeling demand as a renewal-reward process, the simulation, inspired by the production system and available data from a Canadian company, examine the performance of alternative inventory policies and operating procedures. Performance indicators that measure the responsiveness and inventory on hand show trade-offs between them in order to supply relevant information to decision makers. Experiments compare make-to-order and make-to-stock scenarios with various inventory parameters as well as introducing variability to examine the model’s robustness under uncertainty. The system under consideration consists of three main processes to manufacture a finished product from raw materials. The first process fabricates metal and electrical components from raw materials. Second, a worker assembles components into a semi-finished product. The third requires information from the customer in order to customize the product according to their needs, and test the unit to ensure its quality. The company, known for their well-designed products and exceptional customer service, wants to improve the accuracy of their leadtime promising. The current MRP control system assumes a completely make-to-order environment where every piece of WIP has a customer order attached to it. However, a forecast of orders likely to materialize from the sales quotes allows production to initiate jobs before the actual order arrives. The approach taken to analyzing this system involves studying the make-to-stock, make-to-order decision at two stock points, components and semi-finished units. The operating procedures examine four possible stocking strategies: holding no inventory, holding only component or semi-finished inventory, and holding both components and semi-finished units. Simulation experiments determine the trade-off between holding inventory and the responsiveness to the customer for each operating procedure. Sources of randomness introduced to processing time, capacity, and demand, show how they respond to added variability. The simulation experiments indicate that holding no inventory, and waiting for a customer order to initiate jobs, results in unstable performance. In order to achieve a stable make-to-order system, it would be necessary to have a fifty percent reduction in demand or product cycle time, a capacity expansion, or forecasting method. In the absence of an accurate forecast model, holding inventory is necessary for an acceptable level of performance. Component inventory is useful as many components are common among a number of products. Suitable component inventory can lead to customer orders typically fulfilled within two weeks. Adding semi-finished inventory can reduce the customer lead-time to under a week though requires stocking at least a few of each semi-finished unit. Holding semi-finished inventory without component stock is possible. However, it is necessary that the replenishment quantity be three or more units ordered at a time. Otherwise, the setup time for components exceeds the allowable limits and resource queues become unstable, much like the completely make-to-order scenario. Using an order-up-to parameter for semi-finished stock can further decrease the setup time incurred per unit. The model is robust to randomness in job times, though it is component stock, which provides an effective buffer to this variability. Machine breakdowns begin to affect responsiveness measures if the average time for repair is greater than a week. Reducing the capacity in the assembly and testing processes can provide the same level of service indicating the two resources are underutilized. The analysis of this system shows the current make-to-order model requires some forecast to function in steady state, which is difficult to model without information on the current forecasting processes. Expanding the simulation model to incorporate forecasting or some other means of analysis can improve its accuracy and credibility as a management decision tool.

Intermediate storage system optimization is an essential aspect which this report tends to look upon and putting effort on improving operating efficiency then reducing the capital cost of batch/ semi-continuous or flow production process by looking at the extent of estimating the figures of boxes that are made to be in the intermediate storage system through evaluations. Additionally, intermediate storage can reduce the effects of process parameter variations, such as recipe inaccuracies and operator errors, in which process operations are particularly visible. In a channel of operations, where there are many amount of shift that are inevitable to pass through in order to complete production process to get a finished product. Hence, longer operating horizon, process variations must include a measurable parameter, either shorter or longer to avoid failure of meeting product specification and limitation of meeting end users specification. Intermediate storage system as a back-up function in case of some sudden failure within the production line In this thesis, it is notable to make an amendment, as a way of knowing the accuracy of boxes of bearing work-piece that will be maintaining a certain intermediate storage system to feed the next shift of workstation in a continuous process with accurate or known estimated number of work-piece in a role, until the final product is been made. Hence, in this research, there are many theory that were adopted to give a clear view of what will be obtainable in the whole research both in empirical finding to have a definite result. To achieve the above goal this thesis followed a steps to fulfil its objective. Steps 1 and 2 were to know the strategic plans as well as operating methods through theory also, to know the production line balancing to have a view of time measured through the theory. Step 3 and 4 adoptions of theory and empirical finding to calculate, productivity through the source of cycle time, as well as facility plan and to give analysis of intermediate storage system, in optimization of production line to make a work flow achievable at the end, to meet the customers demand.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A importÃncia da carcinicultura, atividade de criaÃÃo de camarÃo em cativeiro, no mercado do agronegÃcio, em Ãmbito nacional e internacional, toma por base a representatividade nas exportaÃÃes, especialmente para o Brasil, que teve uma expansÃo nos 20 anos, destacando-se entre os maiores produtores no mundo, ocupando o primeiro lugar na AmÃrica Latina. Este crescimento foi impulsionado pela regiÃo Nordeste, cuja produÃÃo ultrapassa os 95% de todo montante nacional. Em contrapartida, a este desenvolvimento, vÃrios estudos apontam para os impactos negativos causados pelos empreendimentos de carcinicultura, no que se refere ao trabalhador, ao meio ambiente e ao uso descontrolado dos recursos naturais. No intuito de focalizar o ser humano dentro do processo produtivo da carcinicultura, este estudo propÃs uma anÃlise dos empreendimentos de carcinicultura implantados no municÃpio de Aracati/CearÃ, por ser o estado do nordeste que responde por 12% da produÃÃo de camarÃo do paÃs, significando uma lideranÃa no ramo, impulsionado pela globalizaÃÃo e a reestruturaÃÃo produtiva. No sentido de ultrapassar os limites da capacidade econÃmica do agronegÃcio, identificaram-se as inter-relaÃÃes entre os processos produtivos, o ambiente e a saÃde dos trabalhadores, atravÃs da descriÃÃo do processo produtivo e de trabalho na carcinicultura no municÃpio de Aracati, os riscos nele gerados, analisando suas implicaÃÃes para o ambiente e para a saÃde dos trabalhadores. A metodologia seguiu trÃs fases para realizaÃÃo da pesquisa empÃrica: aproximaÃÃo com o concreto do trabalho na carcinicultura, seus problemas vivenciados pelos trabalhadores e comunidades atravÃs de reuniÃes com Agentes ComunitÃrios de SaÃde e LideranÃas locais ligados Ãs questÃes ambientais na tentativa de traÃar um diagnÃstico sobre a situaÃÃo; estudo dos processos produtivos, atravÃs de visitas Ãs empresas para coleta de informaÃÃes junto aos responsÃveis pela produÃÃo, seguida de observaÃÃo direta do processo de trabalho e seus riscos ocupacionais e ambientais, orientada por roteiro especÃfico e registrada em diÃrio de campo; anÃlise discursiva, atravÃs da realizaÃÃo de entrevistas semi-estruturadas com trabalhadores da carcinicultura, em seus locais de moradia, complementando as informaÃÃes colhidas e examinadas sua percepÃÃo sobre as condiÃÃes de trabalho e de saÃde. Os resultados indicam que o processo de trabalho na indÃstria da carcinicultura em Aracati, de forma geral, expÃe os trabalhadores a longas jornadas de trabalho; a intenso esforÃo fÃsico nas operaÃÃes de alimentaÃÃo dos viveiros e de despesca; à radiaÃÃo infra-vermelha e ultravioleta, decorrentes da exposiÃÃo permanente ao sol; à inalaÃÃo de metabissulfito de sÃdio e dos gases resultantes de sua diluiÃÃo em Ãgua â tendo se registrado inclusive um caso de morte por edema pulmonar agudo entre os trabalhadores. As alteraÃÃes ambientais tÃm levado à inseguranÃa alimentar, seja pela reduÃÃo de espÃcies nativas do mangue, importantes no cardÃpio e na economia popular, como o caranguejo; seja pela salinizaÃÃo das reservas de Ãgua do municÃpio.

Thesis (MBA (Business Management))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: The vegetable unit of Tiger Brands annually is responsible for the canning of approximately 115,200,000 cans of a variety of vegetables, of which baked beans constitute approximately seventy percent. The canning of baked beans is subject to a number of challenges with regard to the raw materials and equipment used. The challenges involve the approved raw materials, the storage thereof and the condition and age of the equipment in the plant. The baked beans are produced throughout the year and inconsistencies in the final product are a major cause for concern. The primary aim of this study was to determine which cultivar of beans is the most suitable for use in the canning industry and whether other cultivars can be used with some adjustments to the production processes to eliminate the current inconsistencies. A further aim was to make recommendations on how to create more capacity and to increase the quality of the final product. The problem was addressed by analysing the production processes for the three different bean cultivars over a period of approximately three months and determining the behaviour of the different cultivars. It is clear from the data collected that the different cultivars behave differently during the production processes and yield different results at the final stage of inspection. Human intervention during the production processes also played an important role in the quality of the final product of the different bean cultivars. Human interventions are currently necessary due to the age of the equipment, poor maintenance over the years and modifications made to the equipment to try to increase capacity and the quality of the product. Further studies could be conducted in some of the areas excluded from this study, to determine the suitability of other bean cultivars for the canning industry. / AFRIKAANSE OPSOMMING: Die groente-eenheid van Tiger Brands is jaarliks verantwoordelik vir die inmaak van omtrent 115,200,000 blikkies groente van verskillende soorte waarvan gebakte bone omtrent sewentig persent van die volume behels. Die inmaak van die bak bone is onderhewig aan unieke uitdagings ten opsigte van die rou materiaal en masjinerie wat in produksieprosesse gebruik word. Die unieke uitdagings behels die verskille in die goedgekeurde bonekultivars, die opberging daarvan en die toestand en ouderdom van die masjinerie in die aanleg. Die inmaak van die bak bone vind regdeur die jaar plaas en die wispelturige resultate in die finale produk is 'n groot rede tot kommer. Die primêre doelwit van die studie was om te bepaal watter bonekultivar die mees geskikte kultivar vir gebruik in die inmaakbedryf is en of die ander kultivars meer aanvaarbare resultate sal lewer as sekere verstellings in die proses aangebring word om die kwaliteit te verbeter en die teenstrydige resultate uit te skakel. 'n Verdere doelwit was om aanbevelings te maak oor hoe om die kapasiteit van die aanleg te verhoog, sowel as om die kwaliteit van die produk te verbeter. Die probleem is aangespreek deur die data wat oor 'n tydperk van drie maande oor die produksie prosesse vir die drie verskillende kultivars ingesamel is, te analiseer, en die gedrag van die drie verskillende bonekultivars in elke proses te bepaal. Dit is duidelik te sien in die verskeidenheid van ingesamelde data dat die verskillende bonekultivars verskillend reageer gedurende die produksieprosesse en dus verskillende resultate gedurende die finale inspeksieproses lewer. Menslike ingrype in die produksieprosesse speel 'n belangrike rol in die uitkoms van die finale produk se kwaliteit by die verskillende bonekultivars. Die menslike ingrype is tans krities belangrik in die produksieprosesse as gevolg van die ouderdom van die masjinerie, die swak instandhouding wat oor die jare uitgevoer is, asook die wysigings wat aan die masjinerie aangebring is in 'n poging om die kapasiteit van die aanleg te verhoog en om die produk se kwaliteit te verbeter. Verdere studies kan uitgevoer word in sekere van die ander areas wat by hierdie studie uitgesluit is, om te bepaal of ander bonekultivars ook in die inmaakbedryf gebruik kan word.

<p>U disertaciji je prikazan postupak izrade modela informacionog<br />sistema za podršku upravljanju grafičkim procesima. Ovaj model za<br />rezultat ima uspešno praćenje parametara grafičke proizvodnje. U<br />radu su date osnovne teorijske postavke grafičke proizvodnje,<br />grafičkih procesa, informacionih sistema i njihovog modelovanja.<br />Napravljen je apstraktni (high-level) i realni (low-level) model<br />informacionog sistema. Kao validacija modela izvršena je<br />simulacija rada sistema u laboratorijskim uslovima.</p> / <p>The dissertation presents a model of Management Information System for<br />Graphic processes. This model results in a successful monitoring of graphic<br />production parameters. Basic theoretical assumptions involving graphic<br />production, printing processes, information systems, and their modeling vere<br />presented. An abstract (high-level) and real (low-level) model of the<br />information system vere also created. As a validation of the model, a<br />simulations was carried out within the laboratory.</p>

Aliada à geração constante de resíduos estão as dificuldades nas formas de disposição e tratamento, muitas vezes custosas e que não levam em consideração suas características básicas. No Brasil, 60% da composição dos resíduos é matéria orgânica passível de reciclagem por meio do processo de compostagem, um método simplificado e sem custos elevados para o seu tratamento sanitariamente adequado. No entanto, as usinas de compostagem são vistas somente como grandes obras de engenharia, capazes de reduzir o volume de resíduos, produzindo um composto de baixa qualidade e vendido a preços irrisórios. Objetivo. Avaliar as usinas de compostagem do estado de São Paulo em função da qualidade dos compostos e processos de produção. Métodos. Pesquisou-se 14 usinas de compostagem do Estado de São Paulo com diferentes processos de produção. O estudo incluiu 3 fases: 1) caraterização da matéria-prima e do material-base e o estudo dos processos de produção, 2) análise dos compostos: física (densidade real e aparente, granulometria e conteúdo total de contaminantes) e química (micro e macronutrientes e metais pesados), e 3) análises estatísticas. Resultados. Os resultados foram avaliados levando-se em conta as usinas separadamente e o agrupamento realizado de acordo com suas estruturas. As usinas que utilizam os processos com peneiras rotatórias apresentaram melhores resultados quanto ao conteúdo de contaminantes e granulometria. Nos resultados químicos, as estruturas das usinas não tiveram influência direta. Conclusões. Os compostos não apresentaram alta qualidade mas podem ser considerados como condicionadores de solo. O problema com as usinas não está na sua estrutura mas sim na falta de acompanhamento dos fatores que regem a compostagem no pátio. / Related to the constant generation of waste are the difficulties in the form of their placement and treatmente, many times very costly and often not taking into consideration its basic charactteristics. In Brazil, 60% of waste composition is organic material which could be recycled by means of a composting process, a simple method and without high costs for adequate sanitary treatment. However, the composting plants are seen only as great engineering feats, capable of reducing the volume of waste, producing a low-quality compost that is sold at ridiculous prices. Objetive. To evaluate the composting plants in the state of São Paulo in function of the quality of the composts and production processes. Methods. Fourteen composting plants in the state of São Paulo with different production processes were investigated. The study includes three phases: 1) characterization of raw materials and of base materials and the study of production processes; 2) composto analysis, both physical (real and apparent densities, granulometry and total contaminat contente) and chemical (micro and macro nutrients and heavy metals); and 3) statistical analysis. Results. The results were evaluated taking into account the composting plants separately as well as by grouping them according to their structural characteristics. The plants utilizing processes with rotating sieves presented better results in relation to both contaminat content and granulometry. For the chemical results, the structural characteristics of the composting plants did not have a direct influence. Conclusions. The composts were not of high quality but could be considered as soil conditioners. The problem with the composting plants was not in their structure but in the lack of accompanying factors that govern the process in the composting area.

Aliada à geração constante de resíduos estão as dificuldades nas formas de disposição e tratamento, muitas vezes custosas e que não levam em consideração suas características básicas. No Brasil, 60% da composição dos resíduos é matéria orgânica passível de reciclagem por meio do processo de compostagem, um método simplificado e sem custos elevados para o seu tratamento sanitariamente adequado. No entanto, as usinas de compostagem são vistas somente como grandes obras de engenharia, capazes de reduzir o volume de resíduos, produzindo um composto de baixa qualidade e vendido a preços irrisórios. Objetivo. Avaliar as usinas de compostagem do estado de São Paulo em função da qualidade dos compostos e processos de produção. Métodos. Pesquisou-se 14 usinas de compostagem do Estado de São Paulo com diferentes processos de produção. O estudo incluiu 3 fases: 1) caraterização da matéria-prima e do material-base e o estudo dos processos de produção, 2) análise dos compostos: física (densidade real e aparente, granulometria e conteúdo total de contaminantes) e química (micro e macronutrientes e metais pesados), e 3) análises estatísticas. Resultados. Os resultados foram avaliados levando-se em conta as usinas separadamente e o agrupamento realizado de acordo com suas estruturas. As usinas que utilizam os processos com peneiras rotatórias apresentaram melhores resultados quanto ao conteúdo de contaminantes e granulometria. Nos resultados químicos, as estruturas das usinas não tiveram influência direta. Conclusões. Os compostos não apresentaram alta qualidade mas podem ser considerados como condicionadores de solo. O problema com as usinas não está na sua estrutura mas sim na falta de acompanhamento dos fatores que regem a compostagem no pátio. / Related to the constant generation of waste are the difficulties in the form of their placement and treatmente, many times very costly and often not taking into consideration its basic charactteristics. In Brazil, 60% of waste composition is organic material which could be recycled by means of a composting process, a simple method and without high costs for adequate sanitary treatment. However, the composting plants are seen only as great engineering feats, capable of reducing the volume of waste, producing a low-quality compost that is sold at ridiculous prices. Objetive. To evaluate the composting plants in the state of São Paulo in function of the quality of the composts and production processes. Methods. Fourteen composting plants in the state of São Paulo with different production processes were investigated. The study includes three phases: 1) characterization of raw materials and of base materials and the study of production processes; 2) composto analysis, both physical (real and apparent densities, granulometry and total contaminat contente) and chemical (micro and macro nutrients and heavy metals); and 3) statistical analysis. Results. The results were evaluated taking into account the composting plants separately as well as by grouping them according to their structural characteristics. The plants utilizing processes with rotating sieves presented better results in relation to both contaminat content and granulometry. For the chemical results, the structural characteristics of the composting plants did not have a direct influence. Conclusions. The composts were not of high quality but could be considered as soil conditioners. The problem with the composting plants was not in their structure but in the lack of accompanying factors that govern the process in the composting area.

Rising South African electricity prices and reduced sales following the 2008 economic recession have led cement manufacturers to seek ways to reduce production costs. Prior research has shown that reduced electricity costs are possible by shifting load from expensive Eskom peak pricing periods to lower cost times. Due to the complex considerations and variables in cement production, this is not typically implemented. Several simulation and optimisation models are available in literature to schedule plant operation in an electricity cost effective manner. However, these models have not been implemented in practice. The simulation models are reviewed and evaluated for the task of scheduling cement production on South African factories. A model is identified to be implemented, and the requirements for implementing this model on a cement factory are investigated. A computerised management system is designed to automatically incorporate the required information and data to implement the optimisation model on a practical level. An interface is also designed to allow factory personnel access to the optimised production plan. The system is implemented and evaluated through system level testing. Four case studies are presented within which the system is implemented on South African cement factories. The performance of the system is evaluated over a nine month period, within which a total cost saving of R8.6-million is reported. / Thesis (MIng (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.

Rising South African electricity prices and reduced sales following the 2008 economic recession have led cement manufacturers to seek ways to reduce production costs. Prior research has shown that reduced electricity costs are possible by shifting load from expensive Eskom peak pricing periods to lower cost times. Due to the complex considerations and variables in cement production, this is not typically implemented. Several simulation and optimisation models are available in literature to schedule plant operation in an electricity cost effective manner. However, these models have not been implemented in practice. The simulation models are reviewed and evaluated for the task of scheduling cement production on South African factories. A model is identified to be implemented, and the requirements for implementing this model on a cement factory are investigated. A computerised management system is designed to automatically incorporate the required information and data to implement the optimisation model on a practical level. An interface is also designed to allow factory personnel access to the optimised production plan. The system is implemented and evaluated through system level testing. Four case studies are presented within which the system is implemented on South African cement factories. The performance of the system is evaluated over a nine month period, within which a total cost saving of R8.6-million is reported. / Thesis (MIng (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.

Esta pesquisa foi baseada em um projeto de Stone Mastic Asphalt – SMA na faixa I da especificação ET-DE-P00-031 do Departamento de Estradas de Rodagem do Estado de São Paulo, com ligante modificado por polímero, classificação 60/85, em trecho experimental da rodovia ERS-122, km 6+400 ao km 7+000. O volume elevado de veículos pesados neste trecho e as deformações decorrentes desta carga motivaram o estudo de novas tecnologias. Foram realizados ensaios laboratoriais para confirmar a dosagem da mistura e determinar as propriedades mecânicas através de ensaios de módulo de resiliência, resistência a tração na compressão diametral e deformação permanente em trilha de roda. A mistura apresentou bom desempenho a deformação permanente, módulo de resiliência e resistência a tração no teor de projeto. Além disso, foi analisado o processo executivo da mistura, desde a produção do agregado, passando pelo processo de usinagem, transporte, lançamento e compactação. Inicialmente, foi executada pista teste na praça de pedágio do Departamento Autônomo de Estradas de Rodagem do Estado do Rio Grande do Sul (DAER/RS) localizada no município de Portão/RS para posterior execução no trecho experimental. Constatou-se que o processo de usinagem produziu misturas com variações positivas de até +0,3% em relação ao teor de ligante, influenciando no desempenho da mistura no que se refere aos ensaios de desempenho. Os resultados e análises apontam para uma mistura que requer uma metodologia de controle de qualidade efetiva, mas que mesmo com algumas variações, o revestimento ainda apresentou bom desempenho. / This research was based on a Stone Mastic Asphalt- SMA project in the grading smolop #1 of ET-DE-P00/031 specification of São Paulo Highways Department , with modified binder, grade 60/85, in a test section in ERS-122 highway, between km 6+400 and km 7 +0. The high volume of heavy vehicles on this highway and the resulting deformations, led to the study of new technologies. Laboratory tests were conducted to confirm the mixture design and determine the mechanical properties through resilient modulus test, tensile strength in diametrical compression and wheel-tracking test. The mixture had a good performance at the Wheel-tracking test, resilient modulus and tensile strength at the design binder content. In addition, it was analyzed the production process of the mixture, since the production at the crushing plant, mix plant facilities, delivery and compaction process. Initially, the test was performed at the toll plaza of DAER/RS in the city of Portão/RS for later execution in test section. It was found that the mixing plant produced mixtures up to 0.3% over the design binder content, influencing in the performance of the mixture on performance tests. The results and analyzes indicate that the mixture requires a effective methodology of quality control, but even with some variations, the layer still performed well.