No description available.

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.

No description available.

As altas exigências que impõe o mercado globalizado, a complexidade dos sistemas produtivos de manufatura atuais e os avanços na Tecnologia da Informação são fatos que resgatam a importância da Programação Detalhada da Produção para as empresas. A pesar de bastante consolidada e difundida, a abordagem clássica MRP / ERP não atende plenamente as necessidades em ambientes de produção intermitente. A Programação Detalhada da Produção com capacidade finita dos recursos, atualmente contemplada nos sistemas APS (Advanced Planning & Scheduling), constitui uma alternativa interessante para melhor cumprir prazos de entrega em ambientes com roteiros de produção complexos e produção make-to-order (MTO). O problema de pesquisa ora estudado contempla o ensino de modelos de Planejamento e Controle da Produção (PCP) em um ambiente de produção intermitente, com foco na Programação Detalhada da Produção e nos sistemas MRP e APS. Propõe-se um plano de ensino que busca apresentar e diferenciar essas abordagens. O plano contempla o uso de um caso didático A Fábrica de Skates. De uma forma lúdica, porém realista, o caso apresenta, nas suas cinco etapas, duas situações hipotéticas de uso de sistemas de programação. O primeiro, um MRP para planejamento da fábrica de skates e, no segundo, um APS utilizado pelo fornecedor de eixos. O plano foi aplicado pela primeira vez em uma turma de graduação do curso de Engenharia de Produção. Nesta dissertação, é apresentada uma descrição detalhada do caso didático, junto ao plano de ensino. A pesquisa verificou, mediante análise das atividades do caso e de um questionário de avaliação, a utilidade dos recursos elaborados, como também que as estratégias aplicadas ajudaram na aprendizagem. Nesta primeira aplicação, constatou-se também que a alta carga de trabalho dos alunos no semestre e o pouco peso dado à nota final do caso didático foram fatores que inibiram melhores resultados. Para futuras aplicações, o caso didático pode ser aprimorado: novas etapas contemplando outros assuntos importantes para a disciplina PCP e análise de alternativas para substituição dos softwares empregados são exemplos de melhorias. / The high standard of competition in global market, the complexity of current manufacturing systems and the advances in Information Technology highlight the importance of the detailed production scheduling. Although classical approaches such as MRP perform this function quite well in different situations, these systems do not perform well in make-to-order (MTO) production systems. The finite capacity scheduling currently embedded within the software called APS (Advanced Planning & Scheduling) is a more interesting approach to achieve better performance in meeting due dates in production environments with complex routings and MTO strategy. Thus, the problem addressed in this study concerns the teaching of Production Planning and Control (PPC) models for intermittent production, with focus on the detailed production scheduling using MRP and APS approaches. In order to that, a teaching plan is proposed to present and differentiate these approaches. It includes the use of an educational case study named \"The Skateboard Factory\". In a playful but realistic way, the case presents, in its five stages, two hypothetical situations of use of scheduling systems. First, an MRP approach for planning in the skateboard factory, and second, one APS approach used by the truck supplier. The teaching plan was first applied to an undergraduate degree Production Engineering program. In this dissertation, a detailed description of the educational case study, along with the teaching plan, is provided. The results achieved in the case study and the students evaluation attest to the usefulness of the resources designed, and also that the strategies applied really improved the learning process. In this first application, it was also observed that high workload and the little weight in the final grade of the case study inhibit better results. In future applications, the case can be enhanced to include new stages on other important issues of the PPC discipline and the replacement of the software used.

No atual contexto do planejamento e controle da produção, existe uma necessidade de uma melhor utilização do processo de negócio que norteia o desenvolvimento de todos os seus planos, conhecido como gestão da demanda. Nesse assunto, a existência de literatura adequada e de modelos ou formalismos que visam facilitar a compreensão e utilização do processo em si, é rara, e por muitas vezes, insuficiente. Dessa forma, a gestão da demanda acaba por não ser amplamente conhecida, e, por conseqüência, torna-se sub-utilizada nas organizações. Assim, este trabalho visa colaborar para a solução dessa questão, contribuindo para a geração de um modelo formal que possa ser útil tanto à comunidade acadêmica quanto à empresarial interessada. / In current context of the Manufacturing Planning and Control Systems there is a need for a better use of the business process that address the development of alI its plans, the Demand Management process. The existence of appropriate literature and models or formalisms that aims to help a better understanding and usage of this business process is rare and insufficient. ln that way, the Demand Management process is not being known thoroughly and, for consequence, it is not properly used in some organizations. Thus, this work aims to collaborate for the solution of this problem, contributing to a formal model generation that can be useful for the academic and managerial community interested.

As altas exigências que impõe o mercado globalizado, a complexidade dos sistemas produtivos de manufatura atuais e os avanços na Tecnologia da Informação são fatos que resgatam a importância da Programação Detalhada da Produção para as empresas. A pesar de bastante consolidada e difundida, a abordagem clássica MRP / ERP não atende plenamente as necessidades em ambientes de produção intermitente. A Programação Detalhada da Produção com capacidade finita dos recursos, atualmente contemplada nos sistemas APS (Advanced Planning & Scheduling), constitui uma alternativa interessante para melhor cumprir prazos de entrega em ambientes com roteiros de produção complexos e produção make-to-order (MTO). O problema de pesquisa ora estudado contempla o ensino de modelos de Planejamento e Controle da Produção (PCP) em um ambiente de produção intermitente, com foco na Programação Detalhada da Produção e nos sistemas MRP e APS. Propõe-se um plano de ensino que busca apresentar e diferenciar essas abordagens. O plano contempla o uso de um caso didático A Fábrica de Skates. De uma forma lúdica, porém realista, o caso apresenta, nas suas cinco etapas, duas situações hipotéticas de uso de sistemas de programação. O primeiro, um MRP para planejamento da fábrica de skates e, no segundo, um APS utilizado pelo fornecedor de eixos. O plano foi aplicado pela primeira vez em uma turma de graduação do curso de Engenharia de Produção. Nesta dissertação, é apresentada uma descrição detalhada do caso didático, junto ao plano de ensino. A pesquisa verificou, mediante análise das atividades do caso e de um questionário de avaliação, a utilidade dos recursos elaborados, como também que as estratégias aplicadas ajudaram na aprendizagem. Nesta primeira aplicação, constatou-se também que a alta carga de trabalho dos alunos no semestre e o pouco peso dado à nota final do caso didático foram fatores que inibiram melhores resultados. Para futuras aplicações, o caso didático pode ser aprimorado: novas etapas contemplando outros assuntos importantes para a disciplina PCP e análise de alternativas para substituição dos softwares empregados são exemplos de melhorias. / The high standard of competition in global market, the complexity of current manufacturing systems and the advances in Information Technology highlight the importance of the detailed production scheduling. Although classical approaches such as MRP perform this function quite well in different situations, these systems do not perform well in make-to-order (MTO) production systems. The finite capacity scheduling currently embedded within the software called APS (Advanced Planning & Scheduling) is a more interesting approach to achieve better performance in meeting due dates in production environments with complex routings and MTO strategy. Thus, the problem addressed in this study concerns the teaching of Production Planning and Control (PPC) models for intermittent production, with focus on the detailed production scheduling using MRP and APS approaches. In order to that, a teaching plan is proposed to present and differentiate these approaches. It includes the use of an educational case study named \"The Skateboard Factory\". In a playful but realistic way, the case presents, in its five stages, two hypothetical situations of use of scheduling systems. First, an MRP approach for planning in the skateboard factory, and second, one APS approach used by the truck supplier. The teaching plan was first applied to an undergraduate degree Production Engineering program. In this dissertation, a detailed description of the educational case study, along with the teaching plan, is provided. The results achieved in the case study and the students evaluation attest to the usefulness of the resources designed, and also that the strategies applied really improved the learning process. In this first application, it was also observed that high workload and the little weight in the final grade of the case study inhibit better results. In future applications, the case can be enhanced to include new stages on other important issues of the PPC discipline and the replacement of the software used.

No atual contexto do planejamento e controle da produção, existe uma necessidade de uma melhor utilização do processo de negócio que norteia o desenvolvimento de todos os seus planos, conhecido como gestão da demanda. Nesse assunto, a existência de literatura adequada e de modelos ou formalismos que visam facilitar a compreensão e utilização do processo em si, é rara, e por muitas vezes, insuficiente. Dessa forma, a gestão da demanda acaba por não ser amplamente conhecida, e, por conseqüência, torna-se sub-utilizada nas organizações. Assim, este trabalho visa colaborar para a solução dessa questão, contribuindo para a geração de um modelo formal que possa ser útil tanto à comunidade acadêmica quanto à empresarial interessada. / In current context of the Manufacturing Planning and Control Systems there is a need for a better use of the business process that address the development of alI its plans, the Demand Management process. The existence of appropriate literature and models or formalisms that aims to help a better understanding and usage of this business process is rare and insufficient. ln that way, the Demand Management process is not being known thoroughly and, for consequence, it is not properly used in some organizations. Thus, this work aims to collaborate for the solution of this problem, contributing to a formal model generation that can be useful for the academic and managerial community interested.

No / Due to significant challenges and increase in competition within the global environment, manufacturing companies need to focus on Manufacturing Planning and Control (MPC) systems in order to gain a competitive edge. This research paper describes a contribution towards the design and implementation of a bespoke MRP II system for a SME company dealing in tool reclamation. The paper covers the investigation of currently available MRP II systems and also investigates the present MPC system of the concerned SME company. On the basis of these investigations, a new/bespoke design has been proposed and developed for an MRP II system that is tailor-made for the aforementioned company. The newly designed MRP II system has been developed (using MS Access and Visual Basic for Application i.e. VBA) as a database planning tool of MPC system and contains the critical modules Demand Management (DM), Rough Cut Capacity Planning (RCCP), Master Production Scheduling (MPS), Material Requirements Planning (MRP), and Capacity Requirements Planning (CRP). The bespoke MRP II system has been tested within the real manufacturing environment existing in the SME company with positive results. The key outcome of the research has shown that even small SME’s can design and implement their own MRPII system, which is particular and relevant to their own special manufacturing environment, using a minimal of time, software and financial resources.

Variations can have substantially negative effects on performance and it is therefore important to investigate how the variations can be reduced or absorbed in an appropriate way for competitiveness. Manufacturing companies are daily exposed to variations and operations managers need to take capacity management decisions with this in mind to secure the delivery capability. The current body of knowledge mainly focus on techniques for root cause analysis for reducing variations, especially in the manufacturing processes, neglecting the fact that both internally and externally generated variations are more or less possible to affect. Buffers are traditionally associated with waste and unfavourable performance, while the right buffers can be of strategic importance. The purpose of this research is therefore to increase the understanding of causes for variations, actions to reduce variations and how buffers can be used to mitigate negative effects of variations related to capacity management in a manufacturing context. Three research studies have been conducted, including four appended papers, to fulfil the purpose. These studies encompassed different combinations of traditional literature reviews, conceptual research with logical reasoning and case study research. The findings demonstrate that working on mitigating negative effects of variations is a complex challenge and not just about choosing to reduce or absorb the variations. In general, it is concluded that the variation management and buffer management include several aspects to consider with implications for the capacity management. In addition, the results indicate that the decisions in manufacturing companies tend to be based on intuition and previous experience due to a lack of decision support. Furthermore, the participating companies perceive that several of their internal routines contribute to their prevailing variations. This research contributes to an awareness of causes for variations that are possible to affect, possible actions to reduce the variations and the purposes of different buffers to absorb variations. This is sought to facilitate a systematic way of working with reducing and absorbing variations, creating support in the variation management and the buffer management from a capacity management perspective. / Variationer kan medföra negativa effekter för en verksamhets prestation och det är därmed viktigt att utforska hur variationerna kan reduceras eller absorberas på lämpligt sätt för att verksamheten ska vara konkurrenskraftig. Tillverkande företag är dagligen exponerade för variationer och produktionschefer behöver beakta detta i kapacitetsadministrationen för att säkerställa leveransförmågan. Befintlig litteratur fokuserar främst på tekniker för att analysera grundorsaker inom tillverkningsprocesserna och ignorerar det faktum att både internt och externt genererade variationer är mer eller mindre påverkbara. Buffertar associeras traditionellt med oönskat slöseri fastän rätt buffertar kan vara av strategisk betydelse. Syftet med denna forskning är därmed att öka förståelsen för orsaker till variationer, åtgärder för att reducera variationer och hur buffertar kan tillämpas för att överkomma negativa effekter av variationer i relation till kapacitetsadministration inom en tillverkningskontext. Tre forskningsstudier, innefattande fyra publikationer, har genomförts för att uppfylla syftet. Dessa studier består av en kombination av traditionella litteraturstudier, konceptuell forskning med logiska resonemang och fallstudier i tillverkande företag. Resultaten visar att arbetet med att hantera negativa effekter av variationer är en komplex utmaning som stäcker sig bortom valet av att reducera eller absorbera variationerna. Generellt dras slutsatsen att det är flertalet aspekter att beakta för variationsadministration och buffertadministration med implikationer för kapacitetsadministrationen. Det visade sig att besluten tenderar att vara baserat på intuition och erfarenheter i tillverkande företag, mycket till följd av en avsaknad av beslutsstöd. Vidare framgår det att de medverkande företagen upplever att flera av deras interna rutiner bidrar till upphovet av variationer. Denna forskning bidrar till en ökad medvetenhet om orsaker till variationer som är påverkbara inom företag, möjliga åtgärder för att reducera variationerna och syftet med olika buffertar för att absorbera variationer. Detta är avsett att underlätta ett systematiskt arbetssätt för att reducera och absorbera variationer, samt utgöra ett stöd för variationsadministration och buffertadministration från ett kapacitetsadministrationsperspektiv. / KOPability