Submitted by ROBSON FLÁVIO CASTRO null (robson.afl@gmail.com) on 2016-05-04T14:03:14Z No. of bitstreams: 1 ROBSON_CASTRO_AUTOARQUIVAMENTO.pdf: 19394323 bytes, checksum: 7e472e92d451cc588e98cedecc565eba (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-05-06T14:50:11Z (GMT) No. of bitstreams: 1 castro_rf_me_bauru.pdf: 19394323 bytes, checksum: 7e472e92d451cc588e98cedecc565eba (MD5) / Made available in DSpace on 2016-05-06T14:50:11Z (GMT). No. of bitstreams: 1 castro_rf_me_bauru.pdf: 19394323 bytes, checksum: 7e472e92d451cc588e98cedecc565eba (MD5) Previous issue date: 2016-03-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Por meio de experimentos baseados em simulação computacional, este trabalho tem como objetivo avaliar o desempenho do Sistema de Coordenação de Ordens (SCO) Simplified Drum-Buffer-Rope (S-DBR) aplicado a ambientes de produção para estoque, denominado Make-to-Availability (MTA). Composto por um conjunto de técnicas, o MTA visa maximizar o nível de serviço a partir da garantia de estoques de produtos acabados para pronta entrega. Nesta pesquisa, são criadas derivações do MTA com as retiradas das técnicas Gerenciamento do Pulmão, Priorização pelo Status do Pulmão e Carga Planejada. O desempenho das derivações é comparado com o MTA em sua forma completa. Para tanto, quatro indicadores de desempenho são utilizados: fill rate, estoque em processo, estoque de produtos acabados e tempo de reposição. Quatro cenários foram simulados, variando as taxas médias de demanda e o coeficiente de variação dos tempos de processamento. O MTA não obteve o melhor desempenho em nenhum dos indicadores, nos quatro cenários, porém a retirada das técnicas não trouxe melhoras significativas na disponibilidade dos produtos, e em alguns casos aumentou extremamente os níveis de estoque e o tempo de reposição. Ao final as técnicas se mostraram importantes para manter a disponibilidade dos produtos com menores níveis de estoque e menor tempo de reposição. / Through experiments with computer simulation, this work aims to evaluate the performance of an Ordering System Coordinator (OSC), Simplified Drum-Buffer-Rope applied to a make to stock environment, called Make-To-Availability (MTA). Composed of a set of techniques, the MTA aims to maximize the level of service from the supply guarantee for immediate delivery. In this research, MTA derivations are created pulling out the techniques Buffer Management, Status of Buffer Prioritization and Planned Load. The performance of derivations was compared with MTA in its complete form. For this purpose, four performance indicators were utilized: fill rate, work in process, finished goods inventory and reposition time. Four scenarios were simulated, with different median demand rates and the coefficient of variation of the process time. The MTA does not obtain the best performance in any indicator, at the four scenarios, however the pulling out of techniques does not bring significant improvement on product availability, and in some cases, stocks and reposition time greatly increased. In the end, the techniques have shown important to keep the availability of products with lower stocks and smaller reposition time.

This thesis discusses and demonstrates the benefits of simulating and optimising a manufacturing control system in order to improve flow of production material through a system with high variety low volume output requirements. The need for and factors affecting synchronous flow are also discussed along with the consequences of poor flow and various solutions for overcoming it. A study into and comparison of various planning and control methodologies designed to promote flow of material through a manufacturing system was carried out to identify a suitable system to model. The research objectives are; • Identify the best system to model that will promote flow, • Identify the potential failure mechanisms within that system that exist and have not been yet resolved, • Produce a model that can fully resolve or reduce the probability of the identified failure mechanisms having an effect. This research led to an investigation into the main elements of a Drum-Buffer-Rope (DBR) environment in order to generate a comprehensive description of the requirements for DBR implementation and operation and attempt to improve the limitations that have been identified via the research literature. These requirements have been grouped into three areas, i.e.: a. plant layout and kanban controls, b. planning and control, and c. DBR infrastructure. A DBR model was developed combined with Genetic Algorithms with the aim of maximising the throughput level for an individual product mix. The results of the experiments have identified new knowledge on how DBR processes facilitate and impede material flow synchronisation within high variety/low volume manufacturing environments. The research results were limited to the assumptions made and constraints of the model, this research has highlighted that as such a model becomes more complex it also becomes more volatile and more difficult to control, leading to the conclusions that more research is required by extending the complexity of the model by adding more product mix and system variability to compare results with the results of this research. After which it will be expected that the model will be useful to enable a quick system response to large variations in product demand within the mixed model manufacturing industry.

High variety and low volume manufacturing environment always been a challenge for organisations to maintain their overall performance especially because of the high level of variability induced by ever changing customer demand, high product variety, cycle times, routings and machine failures. All these factors consequences poor flow and degrade the overall organisational performance. For most of the organisations, therefore, process improvement has evidently become the core component for long term survival. The aim of this research here is to develop a methodology for automating operations in process improvement as a part of lean creative problem solving process. To achieve the stated aim, research here has investigated the job sequence and buffer management problem in high variety/low volume manufacturing environment, where lead time and total inventory holding cost are used as operational performance measures. The research here has introduced a novel approach through integration of genetic algorithms based multi-objective combinatorial optimisation and discrete event simulation modelling tool to investigate the effect of variability in high variety/low volume manufacturing by considering the effect of improvement of selected performance measures on each other. Also, proposed methodology works in an iterative manner and allows incorporating changes in different levels of variability. The proposed framework improves over exiting buffer management methodologies, for instance, overcoming the failure modes of drum-buffer-rope system and bringing in the aspect of automation. Also, integration of multi-objective combinatorial optimisation with discrete event simulation allows problem solvers and decision makers to select the solution according to the trade-off between selected performance measures.

Os modelos de programação e controle Constant Work-In-Process (CONWIP) e Drum-Buffer-Rope (DBR) são mecanismos bastante conhecidos na literatura de Planejamento e Controle da Produção, especialmente, pela robustez e bom desempenho. Esses modelos já foram comparados, sobretudo, em ambientes do tipo flow shop. Há muitos trabalhos que apontam o DBR como superior, outros que sugerem equivalência entre ambos e, em menor proporção, casos onde o CONWIP foi melhor. Contudo, estudos comparativos em ambientes mais complexos, como sistemas com montagem, ainda são escassos na literatura. Diante do exposto, a presente tese visa comparar o CONWIP e o DBR em um ambiente de montagem (assembly flow shop) contra pedido. Para tanto, foram desenvolvidos dois modelos de simulação por eventos discretos e um experimento hierárquico-cruzado, com os seguintes fatores: modelo de programação e controle, posição do gargalo, severidade do gargalo e limite de buffer. Os mecanismos foram avaliados quanto aos indicadores tempo médio de fluxo, lead time médio, utilização do gargalo, percentual de ordens atrasadas e atraso médio. Os resultados demonstraram que, para o ambiente em análise, os modelos se mostraram estatisticamente semelhantes, havendo diferenças significativas apenas para a variável tempo médio de fluxo, o que ratifica e estende conclusões de estudos anteriores. Há evidências de que o CONWIP realiza um controle mais efetivo do estoque em processo e não é significativamente afetado pelas diferentes posições do gargalo. Para o CONWIP, os melhores resultados foram identificados quando a restrição estava no início do sistema, enquanto que para o DBR os melhores resultados foram quando o gargalo estava na última estação da linha de fabricação (operação anterior a montagem). / The Constant Work-In-Process (CONWIP) and Drum-Buffer-Rope (DBR) scheduling and control models are well known mechanisms in the Production Planning and Control literature, especially for robustness and good performance. These models have already been compared, especially, to flow shop environments. There are many papers that point to DBR as superior, others that suggest equivalence between both and, less often, cases were CONWIP was better. However, comparative studies in more complex environments, such as assembly systems, are still rare in the literature. Therefore, this thesis aims to compare CONWIP and DBR in a make-to-order assembly flow shop environment. For that, two models of discrete event simulation and a crossed and nested experiment were developed, with the following factors: scheduling and control model, bottleneck position, bottleneck severity and buffer limit. The mechanisms were evaluated with respect to the indicators mean flow time, mean lead time, bottleneck utilization, percentage tardy and mean tardiness. The results showed that, for the environment under analysis, the models were statistically similar, with significant differences only for the variable mean flow time, which ratifies and extends the conclusions from previous studies. There is evidence that CONWIP performs more effective control of order release and is not significantly affected by the different bottleneck positions. For the CONWIP, the best results were identified when the constraint was at the beginning of the system, while for the DBR the best results were when the bottleneck was at the last station of the manufacturing line (before assembly operation).

The thesis is mainly a study on the Flexible Print Circuit which was producing manufactured. The research investigates how the FPC operates based on related product capacity data in the conjunction of back end MPS system data of producing scheduling database. Due to system and relative data collocation, it helps a salesman to make a better judgment on the outcome of an order before making promises to customers. In addition, this paper is looking into how applying the related production management method increases the number of the entire production and improves the efficiency on the production line. Then it studies how using this method can temporarily meet the needs of customers¡¦ big orders & cut-in orders before promising customers the date of delivery. Regarding manufacturing procedure of FPC, the purpose for increasing actual output is achieving the maximum production capability and the best arranging procedure. All information was given by different groups of employees from FPC industry, including its Sales Department, Production Management Department, Procurement Department and Supply Department; it also derives from the interviews with station managers and high level managers. With situation simulation and case simulation will be revised on current product line¡¦s output and try to bring up production operation model of FPC Industry. Finally, changing production management and station order to achieve its maximum production on FPC.

Submitted by admin tede (tede@pucgoias.edu.br) on 2016-12-09T12:16:23Z No. of bitstreams: 1 GARIBALDI TEIXEIRA NETO.pdf: 1516545 bytes, checksum: 23fcb900cca46f3b3b38e4e063d2454e (MD5) / Made available in DSpace on 2016-12-09T12:16:23Z (GMT). No. of bitstreams: 1 GARIBALDI TEIXEIRA NETO.pdf: 1516545 bytes, checksum: 23fcb900cca46f3b3b38e4e063d2454e (MD5) Previous issue date: 2015-09-23 / This study presents a computer simulation model based on the theory of constraints, the simplified drum-lung-string method and system production to availability. The goal is to use these concepts to build a model of the production system of the searched company, replicate it on a simulation software, and perform interventions in resources with restraint in order to increase its capacity if the system does not meet the demand. The object of this study was a plant in the food industry, data collection related to the production system, was carried out from June 2012 to December 2013, and the simulation process was generated by the end of 2015. The results were reproduction of each of the production areas as well as the RRC and bottlenecks encountered in the production system. Still, interventions applied in the simulated model, were subsequently applied by the company. / Este trabalho apresenta um modelo de simulação computacional baseado na teoria das restrições, no método tambor-pulmão-corda simplificado e no sistema produção para disponibilidade. O objetivo é utilizar estes conceitos para construir um modelo do sistema produtivo da empresa pesquisada, replicá-lo em um software de simulação, e, realizar intervenções nos recursos com restrição afim de aumentar suas capacidades, caso o sistema não atenda à demanda. O objeto deste estudo foi uma fábrica do ramo alimentício, a coleta dos dados relacionadas ao sistema produtivo, foi realizada no período de junho de 2012 a dezembro de 2013, e o processo de simulação foi gerado até o final de 2015. Os resultados obtidos foram a reprodução de cada uma das áreas produtivas, bem como dos gargalos e RRC encontrados no sistema produtivo. Ainda, as intervenções aplicadas no modelo simulado, foram posteriormente aplicadas pela empresa.

Submitted by Lucas Martins Ikeziri (lucas.ikeziri@unesp.br) on 2018-08-13T13:57:43Z No. of bitstreams: 1 Dissertação - Lucas Martins Ikeziri.pdf: 3834872 bytes, checksum: dcbff094cc5b0ef08e5910d9efbb4364 (MD5) / Approved for entry into archive by Minervina Teixeira Lopes null (vina_lopes@bauru.unesp.br) on 2018-08-13T18:33:33Z (GMT) No. of bitstreams: 1 ikeziri_lm_me_bauru.pdf: 3267956 bytes, checksum: 0073dc72ff68b084049d7c710e797002 (MD5) / Made available in DSpace on 2018-08-13T18:33:33Z (GMT). No. of bitstreams: 1 ikeziri_lm_me_bauru.pdf: 3267956 bytes, checksum: 0073dc72ff68b084049d7c710e797002 (MD5) Previous issue date: 2018-06-28 / O gerenciamento de estoques em cadeias de suprimentos vem enfrentando diversos problemas, como baixa rotatividade, altos investimentos em estoque, vendas perdidas por rupturas e alto índice de obsolescência dos produtos estocados. Assim, esta pesquisa tem o objetivo de avaliar a efetividade da técnica Gerenciamento Dinâmico do Pulmão (Dynamic Buffer Management - DBM) como forma de preservar a disponibilidade de produtos destinados à entrega imediata em ambientes que adotem a solução de distribuição e reposição puxada da Teoria das Restrições. Para tanto, foram realizadas simulações no software ProModel utilizando dados estocásticos para o tempo de reposição e cenários com diferentes combinações de demanda. Esta, por sua vez, pode se comportar de duas formas: i) média sem tendência com dois níveis de coeficiente de variação e ii) média com tendência sazonal com dois níveis de intensidade. Dois algoritmos do DBM foram modelados segundo seus princípios constatados na literatura e combinados com parâmetros para ajuste dinâmico do estoque alvo. Os modelos foram avaliados por meio dos seguintes indicadores: fill rate, estoque médio no sistema e rotatividade por atendimento imediato da demanda. Os resultados indicam que para a demanda média sem tendência, desativar o DBM e manter um nível sensato de estoque alvo no sistema inibe ajustes indevidos e garante um bom desempenho do modelo. Contudo, para a demanda média com tendência sazonal, o DBM é altamente recomendado para assegurar a performance do sistema e ajustar os níveis de estoque conforme o padrão da demanda se altera. / Inventory management in supply chains has faced several problems, such as low turnover, high inventory investments, lost sales due to disruptions, and high obsolescence of stored products. Thus, this research aims to evaluate the effectiveness of the Dynamic Buffer Management (DBM) technique as a way of preserving the availability of products destined for immediate delivery in environments that adopt the distribution solution and pull replenishment of the Theory of Constraints (TOC). For that, simulations were performed in the ProModel software using stochastic data for the replenishment time and scenarios with different combinations of demand. This, in turn, can behave in two ways: i) average without trend with two levels of coefficient of variation and ii) average with seasonal trend with two levels of intensity. Two DBM algorithms were modeled according to their principles found in the literature and combined with parameters for dynamic adjustment of the target level. The models were evaluated through the following indicators: fill rate, average inventory in the system and turnover for immediate demand response. The results indicate that for the average demand without trend, disabling DBM and maintaining a sensible level of target level in the system inhibits undue adjustments and ensures good model performance. However, for average demand with seasonal trend, DBM is highly recommended to ensure system performance and adjust inventory levels as the demand pattern changes.

In 1984, Eli Goldratt published his novel “The Goal – a process of ongoing improvement”. Constraints Management has since evolved into a field of study, still widely debated and written about today. Most companies soon realized that the principles of Constraints Management could no longer be ignored to stay competitive. The South African Breweries (now SABMiller plc) is the world's leading brewer in developing markets. The company has dominated the South African liquor market for years and is currently the second largest brewing company in the world, operating in Africa, China, Europe and the USA, yet even a company with this reputation can still be ignoring the basic principles of Constraints Management. This dissertation concentrates on the application of Constraints Management in a selected brewery in South Africa. The measures used in one of SAB’s most successful breweries will be tested against Constraints Management principles, illustrating how the practice of driving performance measures without focusing on the constraint can lead one away from the goal of the company. Rosslyn Brewery is a brewery driven by traditional brewing industry performance measures. The key drivers of the brewery have always been to increase factory efficiency and reduce costs. Rosslyn set the benchmark for packaging efficiency within SAB. The problem is that the packaging operation is not the constraint in the brewery. The throughput of the brewery is determined by the operation feeding into packaging, i.e. filtration. The end result is that even though the packaging lines have the best efficiency, they still have to stop and wait for beer to become available from filtration, resulting in downtime, frustration and eventually costly overtime and weekend work. The core conflict of the brewery is the trade-off between running all the resources as efficiently as possible, and thereby decreasing product cost, and running only the constraint as efficiently as possible, resulting in an increase in throughput. The Thinking Process was used to evaluate the conflict and a solution developed. The solution consists of the following: 1. The brewery has to adopt Constraints Management using the 5 step process of ongoing improvement. The capacity constraint has to be exploited and all other operations subordinated, to ensure that products are not produced for the sake of improving efficiency. 2. The operational measures of the brewery have to be changed from increasing factory efficiency and reducing R/hl to increasing throughput, decreasing inventory and decreasing operating expense. 3. The production schedule and raw material release for the whole plant need to be determined by filtration. This requires a change in the current advanced planning solution to incorporate the principles of Drum-Buffer-Rope. If the decision is made and actions taken, the brewery will be able to survive the next decade, even if there is a further decline in the market. If not, the focus will still be on reducing product cost, whilst improving the efficiency of all operations. This will lead to further line closures and retrenchments, doing nothing more but reducing SABMiller’s potential future capacity and flexibility. / Dissertation (MEng (Management of Technology))--University of Pretoria, 2005. / Graduate School of Technology Management (GSTM) / unrestricted

The thesis concentrates on the International Standard ISO 10014 - Quality management -Guidelines for realizing financial and economic benefits. In the thesis management principles and the simply methodology called PDCA are described. The thesis is focused on the priniple of process approach and nutually beneficial supplier relationship. These methods according to the Standard are applicated: Drum-Buffer-Rope within process approach and the graphical method of supplier rating, the zone control charts and the comprehensive supplier performance evaluation. The benefits from the effective application of these methods and tools are described.