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Método de programação de sistemas de manufatura do tipo Job Shop dinâmico não determinístico. ; Programming method for non-deterministic dynamic Job Shop manufacturing systems.

Araújo Junior, Lindolpho Oliveira de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 29/06/2006 PT
Relevância na Pesquisa
46.22%
Esta tese explora características de sistemas de manufatura celular virtual, de técnicas de escalonamento e despacho em tempo de execução e de algoritmos genéticos para assegurar um alto grau de flexibilidade de rotas de processo e eficiência na programação de tarefas de sistemas de manufatura do tipo (NDDJSS – non-deterministic dynamic job shop system). Desenvolve-se assim, um método de programação baseado em duas novas técnicas, de clustering e de escalonamento e despacho, respectivamente, aplicado a sistemas de manufatura do tipo NDDJSS. Apresentam-se inicialmente os conceitos fundamentais considerados na organização de sistemas de manufatura em células de trabalho e suas implicações em termos de esforço de coordenação e controle das células e das tarefas; a abordagem por organização funcional das células de manufatura virtuais; ascaracterísticas, definições e notação usadas para problemas de escalonamento; a descrição de técnicas de escalonamento e despacho de sistemas de manufatura; aspectos relevantes de computação evolutiva, mais especificamente, de algoritmos genéticos. Em seguida, introduz-se a nova técnica de clustering e a nova técnica de escalonamento e despacho, juntamente com os requisitos e as formulações associadas. A nova técnica de clustering forma células de manufatura virtuais balanceadas quanto ao volume de trabalho...

Utilização de conceitos de células de manufatura no setor de pesponto (costura) em empresas de calçados; The utilization of cellular manufacturing concepts in the sewing sector in shoes industries

Junqueira, Roberta Pinezi
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 02/10/2006 PT
Relevância na Pesquisa
66.22%
O conceito de manufatura enxuta está sendo considerado mais e mais um novo paradigma para um número grande de empresas no mundo. Original da indústria automobilística, o conceito produção enxuta tem sido espalhado para todos os tipos de indústrias. Este trabalho apresenta uma implementação do sistema de produção enxuta em uma indústria calçadista. Tem como objetivo maior apresentar a aplicação dos conceitos de um sistema de formação de células no setor de costura. A criação destas células é vital porque a maioria das atividades são operações intensivamente manuais e células promovem a oportunidade para uma melhor utilização do operário no balanceamento e padronização das operações. As células também permitem uma melhor utilização do espaço e menor estoque intermediário. Um grande desafio para esta atividade é a alta variedade de produtos com alta variedade de seqüências nas operações de costura. Logo, este trabalho apresenta um levantamento bibliográfico, fazendo uma caracterização sobre evoluções dos sistemas de administração da produção salientando a importância do sistema de produção enxuta, bem como conceitos básicos de layout e manufatura celular, apresentando neste contexto sua relevância e medidas utilizadas nas empresas para tomada de decisões e ações. Apresenta também um método para a formação de células em empresas deste setor...

Modelo híbrido de otimização multiobjetivo para formação de células de manufatura; Hybrid multiobjective optimization model for manufacturing cell formation

Pitombeira Neto, Anselmo Ramalho
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 24/03/2008 PT
Relevância na Pesquisa
46.09%
O objetivo deste trabalho é propor um procedimento híbrido para a solução do problema de formação de células de manufatura com réplicas de máquinas. Constrói-se um modelo matemático de otimização multiobjetivo cujos valores das funções-objetivo são obtidos por meio da execução de um modelo de simulação de eventos discretos, o qual representa um sistema de manufatura celular. Em seguida, geram-se soluções eficientes segundo o conceito de otimalidade de Pareto através de um processo de busca por valores ótimos executado por um algoritmo genético. Três funções-objetivo conflitantes são consideradas: inventário em processo, movimentação intercelular e investimento total em máquinas. Um algoritmo de análise de agrupamento é utilizado para a redução do conjunto final de soluções. A eficácia do procedimento é avaliada mediante a aplicação a dois casos da literatura. Os resultados obtidos são analisados e comentados. Conclui-se, por fim, que o procedimento é capaz de gerar um conjunto de configurações sub-ótimas equivalentes para as células de manufatura, representando aproximadamente os trade-offs entre as três funções-objetivo.; The purpose of this work is to propose a hybrid procedure for solving the manufacturing cell formation problem. A multiobjective optimization model is built whose objective function values are realized by running a discrete-event simulation model...

Detailed design of product oriented manufacturing systems

Silva, Sílvio Carmo; Alves, Anabela Carvalho
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em 03/07/2006 ENG
Relevância na Pesquisa
46.12%
This paper describes a procedure for the detailed and repetitive design of manufacturing systems within an approach of constantly fitting production system configuration to the varying production needs of products and, therefore, designing Product Oriented Manufacturing Systems – POMS. The detailed design procedure depart from a set of conceptual manufacturing cell configurations and develops from there, through conceptual cell and workstation instantiation, with basis on available methods, the required manufacturing system and control mechanisms for a product or a family of similar products.; Fundação para a Ciência e a Tecnologia (FCT)

Issues and design approach for product oriented manufacturing systems

Alves, Anabela Carvalho; Silva, Sílvio Carmo
Fonte: Whittles Publishing Publicador: Whittles Publishing
Tipo: Conferência ou Objeto de Conferência
Publicado em //2010 ENG
Relevância na Pesquisa
46.18%
The Product Oriented Manufacturing (POM) concept here presented addresses competition in today’s changing global market of manufacturing companies. It is a challenge to the Function Oriented Manufacturing (FOM) concept supposedly adequate for dealing with demand changes and large product variety without needing reconfiguration. The POM concept evolves from the traditional cellular manufacturing, ultimately aiming at full system integration and coordination for completely processing a product, not parts of it, or a family of similar products, for efficient manufacturing and good customer service. In this respect it is customer order centred. For answering changing demand it draws upon system adaptation exploring several reconfiguration strategies. Due to POM complexity and design focus, a design methodology called GCD was developed and is here briefly described. The first phase, the Generic Design, is emphasized in relation to the others. It is mainly directed to analysing manufacturing companies’ demand market position and current manufacturing system in order to evaluate, at a generic level, the suitability of the POM concept for manufacturing. Further design phases explore alternatives of POM systems to reach a POMS suitable solution.

A framework for understanding cellular manufacturing systems

Silva, Sílvio Carmo; Alves, Anabela Carvalho
Fonte: Elsevier Publicador: Elsevier
Tipo: Conferência ou Objeto de Conferência
Publicado em //2002 POR
Relevância na Pesquisa
66.28%
Many practical benefits, such as superior quality of products and short manufacturing lead times, are usually associated with Cellular Manufacturing. These and other benefits can lead to important competitive advantages of companies. However, to fully achieve these benefits there is a need for an evolution from the traditional concept of CM to the more comprehensive one, which we call Product Oriented Manufacturing. Here systems are dynamically reconfigured for total manufacturing of complete products, not parts only. In this paper, we make a contribution to better understand the nature of cells and POM Systems. Thus a classification framework is presented of the different types of cells that might be formed and seen as building blocks for POMS.

Design of product oriented manufacturing systems

Silva, Sílvio Carmo; Alves, Anabela Carvalho
Fonte: Kluwer Academic Publishers Publicador: Kluwer Academic Publishers
Tipo: Conferência ou Objeto de Conferência
Publicado em //2002 POR
Relevância na Pesquisa
46.09%
A Product Oriented Manufacturing System is designed for the manufacture of a product or a family of similar products. POM may be seen as a development of traditional Cellular Manufacturing and tends to involve more than one cell. A POMS may either be physically organized in a single place or be made of distributed manufacturing or servicing units, thus comprising a virtual system. To be efficient, the POMS design should identify design phases and point to the data, methods and tools that should be used to obtain good design solutions. In this paper, one such methodology is proposed, together with an analysis of the conceptual configuration of the cells that are the building blocks of POM systems.

Understanding Lean Manufacturing According to Axiomatic Design Principles

Reynal, Vicente A.; Cochran, David S.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 204204 bytes; application/pdf
EN_US
Relevância na Pesquisa
46.09%
In this paper, a sequence of implementation steps will be developed through the application of axiomatic design. This sequence will provide a design methodology for lean production which connects manufacturing system design objectives to operation design parameters.; Lean Aerospace Initiative

Lean manufacturing system design and value stream management in a high-mix, low-volume environment

Gates, Matthew David, 1973-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 156 p.; 8235862 bytes; 8253460 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
56.14%
Value Stream Mapping is a powerful tool for identifying sources of waste and for creating the vision for the future state of a production system. As a management tool, however, it lacks in specific focus of roles, responsibilities, and actions required to achieve the future state vision. The limitations become more evident and the problems of execution become exacerbated when multiple value stream projects are launched with limited human resources available. This thesis describes a set of management tools to complement Value Stream Mapping. The tools are expected to improve management visibility and accountability. The design of a lean production system is also proposed in this thesis. The lean production system includes a newly designed layout for the manufacturing cell as well as the "operating system" for the cell. The layout is based on the principles of cellular manufacturing in order to promote flow and improve quality. The operating system includes such things as production batch sizes, product routings, and strategic inventory locations. Based on the future state value stream map and supported by a discrete-event simulation, the new operating system is designed to align the lean strategy with the technical capabilities of the manufacturing line. As confirmed by the simulation...

Development and application of management tools within a high-mix, low-volume lean aerospace manufacturing environment; Management tools within a high-mix, low-volume lean aerospace manufacturing environment

McKenney, Kevin (Kevin Bryan), 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 105 p.; 7553501 bytes; 7559064 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
56.12%
The design and implementation of a lean production system is a complex task requiring an intimate understanding of the fundamental lean principles. Much of the published lean literature is written at a high level of abstraction and contains very basic examples. When lean tools are applied blindly to complex, highly constrained systems, lean implementation becomes challenging and often ineffective. This thesis develops a set of management tools that emphasize the fundamental lean principles and the importance of an overarching value stream level management perspective in an effort to drive appropriate system design decisions and management behavior in such an environment. This thesis proposes the design of a high-mix, low-volume (HMLV) lean production system for implementation at Hamilton Sundstrand, a global supplier of technologically advanced aerospace and industrial products. The system establishes a series of mixed model flow lines based upon the principles of cellular manufacturing. The flow lines operate in a true pull fashion with an optimally sized finished goods supermarket and a strategic, continuous review incoming material ordering policy. In addition, a capacity planning tool, a long term resource cross-training planning tool...

Design of dynamic cellular manufacturing systems / by Mirko M. Bajic.

Bajic, Mirko M.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado Formato: 612931 bytes; application/pdf
Publicado em //2001 EN
Relevância na Pesquisa
56.16%
An analytical approach to the integrated problems of designing the dynamic cellular manufacturing systems layout concurrently with its material flow (handling) requirements, in such a manner that minimises the material handling within the system. The proposed strategy encourages the design of a dynamic layout to identify simultaneously the machine groups, economical machine distribution, and intracell and intercell layouts.; Thesis (Ph.D.)--University of Adelaide, Dept. of Mechanical Engineering, 2001?; Bibliography: leaves 172-184.; xx, 278 leaves : ill. (chiefly col.) ; 30 cm.

Principal component analysis and self organizing map for visual clustering of machine-part cell formation in cellular manufacturing system

Chattopadhyay, Manojit; Dan, Pranab K.; Majumdar, Sitanath
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/01/2012
Relevância na Pesquisa
46.02%
The present paper attempts to generate visual clustering and data extraction of cell formation problem using both principal component analysis (PCA) and self organizing map (SOM) from input of sequence based machine-part incidence matrix. First, the focus is to utilize PCA for extracting high dimensionality of input variables and project the dataset onto a 2-D space. Second, the unsupervised competitive learning of SOM algorithm is used for data visualization and subsequently, to solve cell formation problem based on ordinal sequence data via the node cluster on the SOM map. Although the numerically illustrated results from dataset revealed that PCA has explained most of the cumulative variance of data but in reality when the very large dimensional cell formation problem based on sequence is available then to obtain the clustering structure from PCA projection is become very difficult. Most importantly, in the visual clustering of ordinal data, the use of U-matrix alone can not be efficient to get the cluster structure but with color extraction, hit map, labeling via the SOM node map it becomes a powerful clustering visualization methodology and thus the present research contribute significantly in the research of cellular manufacturing.; Comment: 25 pages...

Manufacturing practices: Antecedents to mass customization

Tu, Qiang; Vonderembse, Mark; Ragu-Nathan, T.S.
Fonte: The International Journal of Production Planning and Control Publicador: The International Journal of Production Planning and Control
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
46.12%
Mass customization is a strategy that many firms are adopting to exploit the demand for products that meet the needs of individual customers. Mass customization capability is a firm's ability to manufacture products that meet a variety of specific customer requirements quickly at a cost that is comparable to mass-produced products. The challenge for manufacturing managers is to find ways to cope with environmental uncertainty and increasing product variety through mass customization without affecting lead-time, cost or quality. Based on data collected from 303 US firms, this study investigates manufacturing practices (re-engineering set-ups, preventive maintenance, cellular manufacturing and quality assurance) that enable firms to enhance mass customization capability. When the sample is divided into firms with high versus low environmental uncertainty, the results show that these manufacturing practices tend to have a greater impact on mass customization capability when environmental uncertainty is high than when it is low.; Journal of production planning and control article, June 2004. Please see www.taylorandfrancisgroup.com for the complete article.

Efficient job scheduling for a cellular manufacturing environment

Dennie, Joshua
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
56.34%
An important aspect of any manufacturing environment is efficient job scheduling. With an increase in manufacturing facilities focused on producing goods with a cellular manufacturing approach, the need arises to schedule jobs optimally into cells at a specific time. A mathematical model has been developed to represent a standard cellular manufacturing job scheduling problem. The model incorporates important parameters of the jobs and the cells along with other system constraints. With each job and each cell having its own distinguishing parameters, the task of scheduling jobs via integer linear programming quickly becomes very difficult and time-consuming. In fact, such a job scheduling problem is of the NP-Complete complexity class. In an attempt to solve the problem within an acceptable amount of time, several heuristics have been developed to be applied to the model and examined for problems of different sizes and difficulty levels, culminating in an ultimate heuristic that can be applied to most size problems. The ultimate heuristic uses a greedy multi-phase iterative process to first assign jobs to particular cells and then to schedule the jobs within the assigned cells. The heuristic relaxes several variables and constraints along the way...

Achieving increased productivity and profitability in an EMS environment using lean manufacturing tools and techniques

Ramkumar, S. Manian
Fonte: SMTA: SMTA Pan Pacific Microelectronics Symposium Publicador: SMTA: SMTA Pan Pacific Microelectronics Symposium
Tipo: Proceedings
EN_US
Relevância na Pesquisa
56.26%
This research paper discusses the various aspects of lean manufacturing and its importance in electronics manufacturing service (EMS) provider environment. The philosophy of lean manufacturing and the various tools and techniques for successful implementation are discussed in detail. The paper also provides extensive coverage of value stream mapping and cellular manufacturing and its relevance in improving the printed wiring board (PWB) assembly process.; "Achieving Increased Productivity and Profitability in an EMS Environment using Lean Manufacturing Tools and Techniques," SMTA Pan Pacific Microelectronics Symposium. Held in Hawaii, US: 18-20 February 2003

Manufacturing practices: antecedents to mass customization

Qiang, Tu; Vonderembse, Mark; Ragu-Nathan, T.S.
Fonte: Taylor and Francis. The definitive copy can be found at http://www.tandf.co.uk/journals/default.asp. Publicador: Taylor and Francis. The definitive copy can be found at http://www.tandf.co.uk/journals/default.asp.
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
46.12%
Mass customization is a strategy that many firms are adopting to exploit the demand for products that meet the needs of individual customers. Mass customization capability is a firm's ability to manufacture products that meet a variety of specific customer requirements quickly at a cost that is comparable to mass-produced products. The challenge for manufacturing managers is to find ways to cope with environmental uncertainty and increasing product variety through mass customization without affecting lead-time, cost or quality. Based on data collected from 303 US firms, this study investigates manufacturing practices (re-engineering set-ups, preventive maintenance, cellular manufacturing and quality assurance) that enables firms to enhance mass customization capability. When the sample is divided into firms with high versus low environmental uncertainty, the results show that these manufacturing practices tend to have a greater impact on mass customization capability when environmental uncertainty is high than when it is low.; RIT community members may access full-text via RIT Libraries licensed databases: http://library.rit.edu/databases/

Product clustering for focused factories and cellular manufacturing

Batista, Judith
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
66.32%
In the past, clustering analysis techniques have been broadly utilized to segment markets. Recent studies (Berry et al. 1991) have used market-based clustering to examine manufacturing operations required to be competitive in different market segments. These authors proposed a methodology to categorize a set of products based on their similarity across a set of key variables, such as order-winning criteria, time considerations and volume levels. Their method incorporated the Agglomerative Hierarchy with k-Means Refinement Model to identify groups of similar products to be manufactured in a focused-factory. While many other multivariate clustering methods exist in the literature, the application of these methods to focused factory development is missing. Therefore, this thesis explores the use of other clustering methods for this purpose and incorporates the application of multivariate clustering analysis to support the formation of manufacturing cells. In the case of cellular manufacturing, existing methods rely solely on process similarity to define which products should be grouped together and manufactured in the same cell. Additional attributes, such as volume, setup time, quality and delivery lead times, have been ignored in the literature. Motivated by the need to consider multiple criteria in the formation of focused factories and manufacturing cells...

PERFORMANCE COMPARISON BETWEEN A CLASSIC PARTICLE SWARM OPTIMIZATION AND A GENETIC ALGORITHM IN MANUFACTURING CELL DESIGN

RODRÍGUEZ LEÓN,JOHANNA; QUIROGA MÉNDEZ,JABID EDUARDO; ORTIZ PIMIENTO,NESTOR RAUL
Fonte: DYNA Publicador: DYNA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2013 EN
Relevância na Pesquisa
46.09%
This article studies the performance of two metaheuristics, the Particle Swarm Optimization (PSO) and the Genetic Algorithm (GA), in the manufacturing cell formation problem of a factory that needs to organize three production cases in an efficient way for four, five and six manufacturing cells to produce 30, 40 and 50 different products to be processed in 10, 10 and 20 type machines, respectively. The procedure for adjusting the particular parameters of each algorithm is implemented through a Design of Experiments which includes their own analysis of variance. Both algorithms are implemented in Matlab®. The results obtained by each meta heuristic are compared in terms of the cost of the best solution found and the execution time used to find that solution, so that it is possible to establish which methodology is the most appropriate when solving this optimization problem.

Linear programming embedded particle swarm optimization for solving an extended model of dynamic virtual cellular manufacturing systems

Rezazadeh,H.; Ghazanfari,M.; Sadjadi,S. J.; Aryanezhad,Mir.B.; Makui,A.
Fonte: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico Publicador: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2009 EN
Relevância na Pesquisa
66.25%
The concept of virtual cellular manufacturing system (VCMS) is finding acceptance among researchers as an extension to group technology. In fact, in order to realize benefits of cellular manufacturing system in the functional layout, the VCMS creates provisional groups of resources (machines, parts and workers) in the production planning and control system. This paper develops a mathematical model to design the VCMS under a dynamic environment with a more integrated approach where production planning, system reconfiguration and workforce requirements decisions are incorporated. The advantages of the proposed model are as follows: considering the operations sequence, alternative process plans for part types, machine time-capacity, worker time-capacity, cross-training, lot splitting, maximal cell size, balanced workload for cells and workers. An efficient linear programming embedded particle swarm optimization algorithm is used to solve the proposed model. The algorithm searches over the 0-1 integer variables and for each 0-1 integer solution visited; corresponding values of integer variables are determined by solving a linear programming sub-problem using the simplex algorithm. Numerical examples show that the proposed method is efficient and effective in searching for near optimal solutions.

Reverse Logistics Models and Algorithms: Optimizing WEEE Recovery Systems

Mar-Ortiz,Julio; González-Velarde,José Luis; Adenso-Díaz,Belarmino
Fonte: Centro de Investigación en computación, IPN Publicador: Centro de Investigación en computación, IPN
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 EN
Relevância na Pesquisa
46.16%
This is a summary of the author's PhD thesis supervised by Jose Luis González-Velarde (Tecnológico de Monterrey, Mexico) and Belarmino Adenso-Díaz (Universidad de Oviedo, Spain) and defended on October 11, 2010 at the Tecnológico de Monterrey. The thesis is written in English and is available from the author upon request. This research focuses on Reverse Logistics. Its main objective is to develop mathematical programming models and algorithms to optimize emerging Waste of Electric and Electronic Equipment (WEEE) collection systems. The thesis begins with an overview of the WEEE collection process and identifies key strategic decision areas which impact the performance of a collection system. It specifically identifies three closely interrelated problems within the logistics-manufacturing interface: network design, vehicle routing and cellular manufacturing (disassembly). Even though there is plenty of published literature on each of these individual problems, this research bridges a gap in existing literature on vehicle routing and cellular disassembly systems. The research aims to provide efficient solution approaches to optimize WEEE collection systems, therefore it uses real-world data and case studies (when possible) to test the proposed solution procedures. Computational results using real data show that the proposed methods outperform real existing approaches to reverse logistics.