Group technology: amalgamation with design of organisational structures

Group technology has been studied extensively from an ‘industrial engineering’ perspective (layout, scheduling, workflow, etc.), but less often from an organisational design viewpoint. To study this implication of group technology, the approach of applied systems theory for the design of organisational structures was used as framework for analysis in three empirical cases. To increase the reliability of findings from the analysis of these three empirical cases, five more cases were drawn from archival search. Cluster analysis and product flow analysis were the methods used for forming groups of machines and employees in manufacturing cells, whereas the coding of parts was not employed to this end. Furthermore, the results indicate that the implementation of group technology generally meets shifts in performance requirements caused by competitive pressures, particularly flexibility and responsiveness, albeit the companies considered group technology only when under pressure of ‘poor’ business performance. However, group technology is not always a solution to challenges that companies experience; one empirical case shows that defunctionalisation and scheduling with virtual groups was more beneficial. Nevertheless, when the introduction of group technology is feasible, it also allows firms to consider delegating responsibility for production planning and scheduling to lower levels in the hierarchy and semi-autonomous groups as an alternative to ‘complex’ software applications (a socio-technical approach). Whereas the current study sheds light on the relationship between group technology and design of organisational structures, further research is necessary into the design of these structures and their relationship to group technology

Psychological Capital as a Mediator Between Team Cohesion and Productivity

Organizations attempting to optimize productivity are seeking new ways to develop psychological capital in teams. The researcher conducted a quantitative study to determine whether team cohesion, as assessed by the Revised Group Environment Questionnaire (RGEQ), impacts team productivity, as assessed by the Performance Measurement Team (PMT) Manufacturing Resource System (MRS); whether this relationship can be attributed to a team\u27s level of psychological capital, as assessed by the Psychological Capital Questionnaire (PCQ-12); and whether psychological capital mediates the relationship between team cohesion and team productivity. Forty-five PMTs in a large U.S. defense manufacturing organization were surveyed using the PCQ-12 and the RGEQ, and their respective PMT MRS productivity levels were recorded. Barron and Kenny\u27s 4-step mediation analysis was employed using simple and multiple regression to determine whether a team\u27s level of cohesion significantly contributes to its productivity and if its level of psychological capital mediates the relationship between cohesion and productivity. The results indicated that team cohesion does not predict team productivity and that psychological capital is not a mediator of team cohesion and productivity. Although cohesion and psychological capital have a significant positive effect on supervisor performance ratings, the effect is diminished when viewing the objective measure of productivity. The study promotes positive social change in the workplace by elevating awareness of the effect of team cohesion on the psychological states of manufacturing workers. Understanding these relationships will help organizations to implement teaming methods that support the efficiencies and well-being of employees

Problem specific heuristics for group scheduling problems in cellular manufacturing

The group scheduling problem commonly arises in cellular manufacturing systems, where parts are grouped into part families. It is characterized by a sequencing task on two levels: on the one hand, a sequence of jobs within each part family has to be identified while, on the other hand, a family sequence has to be determined. In order to solve this NP-hard problem usually heuristic solution approaches are used. In this thesis different aspects of group scheduling are discussed and problem specific heuristics are developed to solve group scheduling problems efficiently. Thereby, particularly characteristic properties of flowshop group scheduling problems, such as the structure of a group schedule or missing operations, are identified and exploited. In a simulation study for job shop manufacturing cells several novel dispatching rules are analyzed. Furthermore, a comprehensive review of the existing group scheduling literature is presented, identifying fruitful directions for future research

Production Scheduling

Generally speaking, scheduling is the procedure of mapping a set of tasks or jobs (studied objects) to a set of target resources efficiently. More specifically, as a part of a larger planning and scheduling process, production scheduling is essential for the proper functioning of a manufacturing enterprise. This book presents ten chapters divided into five sections. Section 1 discusses rescheduling strategies, policies, and methods for production scheduling. Section 2 presents two chapters about flow shop scheduling. Section 3 describes heuristic and metaheuristic methods for treating the scheduling problem in an efficient manner. In addition, two test cases are presented in Section 4. The first uses simulation, while the second shows a real implementation of a production scheduling system. Finally, Section 5 presents some modeling strategies for building production scheduling systems. This book will be of interest to those working in the decision-making branches of production, in various operational research areas, as well as computational methods design. People from a diverse background ranging from academia and research to those working in industry, can take advantage of this volume

Projecto dinâmico de sistemas de produção orientados ao produto

Tese de Doutoramento em Engenharia de Produção e SistemasLeanness e agilidade são necessidades importantes das empresas de manufactura na era actual da economia global num mercado intensamente concorrencial, de grande variabilidade e perturbação. De uma forma resumida pode-se dizer que as respostas estratégicas a estas necessidades, no âmbito da produção, são a Produção Lean e a Produção Ágil. A primeira aponta para que o sistema seja convenientemente ajustado às necessidades de produção, numa lógica sincronizada de produção desde a transformação das matérias primas até à distribuição do produto ao cliente, evitando toda a espécie de desperdícios e, portanto, explorando o que se tem designado por produção JIT. A Produção Ágil requer que os sistemas de produção tenham agilidade para rapidamente responderem às variações das necessidades de produção resultantes das variações da procura, i.e. quantidade e variedade de produto. Aparentemente ambas as estratégias confluem num objectivo comum, nomeadamente a resposta rápida da produção às variações da procura através de um ajustamento dinâmico e adequado à variação consequente das necessidades de produção. Nesta tese propõe-se que esse ajustamento seja realizado recorrendo aos Sistemas de Produção Orientados ao Produto (SPOP) que, no essencial, podem ser definidos como sistemas reconfiguráveis formados por conjuntos interligados e complementares de células de produção reconfiguráveis, destinados a, de forma coordenada e sincronizada, fabricar os componentes de um produto ou família de produtos similares, e realizar a sua montagem para entrega rápida ao cliente. A agilidade resulta do requisito de reconfiguração dinâmica dos SPOP face à variação da procura. Devido à complexidade de projecto de SPOP, propõe-se uma metodologia de apoio ao seu projecto e reconfiguração, designada de metodologia GCD por abranger três níveis de concepção, nomeadamente o estratégico, designado de Genérico, o Conceptual e o Detalhado. A metodologia guia o projectista através destas três fases, enquadradas por um conjunto de actividades de projecto sucessivas e interrelacionadas, e sugerindo métodos que podem ser usados para levar a cabo cada actividade. Uma recolha importante de métodos é feita neste contexto. Demonstra-se a utilização da metodologia através de um exemplo de aplicação de projecto de SPOP. Este trabalho baseou-se numa variedade de conceitos conhecidos da literatura e outros propostos e inerentes à metodologia GCD. Portanto uma contribuição ontológica no domínio da investigação é também apresentada sendo de realçar os conceitos de configurações conceptuais, configurações de postos de trabalho, configurações operacionais e modos operatórios de células de produção. No sentido de facilitar a utilização da metodologia é proposto um Sistema assistido por computador de Apoio ao Projecto de SPOP, o SAP_SPOP, e é dada uma contribuição para o desenvolvimento de um seu protótipo. Este sistema está estruturado em três componentes fundamentais: uma base de dados, uma base de métodos e um motor de projecto, designado de SPOP designer. Este inclui um módulo facilitador da interacção entre os elementos do sistema, e o utilizador com as bases de dados e de métodos, facilitando também o acesso a métodos que podem estar residentes na máquina, i.e. computador, do sistema ou distribuídos por vários servidores e acessíveis via Internet ou intranets. Sempre que haja necessidade de projectar SPOP e obter rapidamente soluções de configurações de SPOP o sistema poderá ser usado promovendo o processo de projecto e reconfiguração frequente do SPOP para melhorar a produtividade de empresas industriais através de melhores sistemas de produção.Leanness and agility are important requirements of manufacturing companies in the actual era of global economy and highly competitive variable markets. In a simplified view, it may be said that Lean Production and Agile Production are the strategic answers to these requirements. The first requires a good production systems fit to production requirements from raw materials to finished product delivery, aiming at minimizing waste of every kind and therefore exploring what has been known as JIT Production. The second calls for production systems agility for adaptation to variable production requirements derived from continuous changing on product demand variety and quantity. Apparently, both strategies focus on a common objective, namely that of quick manufacturing response to variable market requirements through a dynamic and suitable fit of the manufacturing system to the corresponding changing production requirements. This thesis suggests that such fit can be achieved through Product Oriented Manufacturing Systems (POMS) which in simple terms may be defined as reconfigurable manufacturing systems formed from sets of interlinked reconfigurable manufacturing cells for coordinated and synchronized fabrication of components and assembly of a product or a family of similar products to quick delivery to customers. Due to POMS design complexity it is proposed a design and reconfiguration methodology for POMS, referred as the GCD methodology because it deals with system design at three planning levels or phases, namely the strategic, referred as Generic, the Conceptual and the Detailed. The methodology guides the designer through these three phases, involving a set of interlinked successive design activities suggesting methods that may be used by a POMS designer to carry out each design activity. A set of important methods were collected for this. The use of the methodology is demonstrated through a POMS design application example. This work had to draw upon important concepts established in the literature and also put forward new ones, contributing, this way, for the ontological development of the scientific domain of the investigation. In particular it must be emphasized the concepts of conceptual and operational cells and also those of cell operating modes. In order to give a better utility to the methodology and facilitate de POMS design task a computer aided design systems for POMS, the CADS_POMS, has been proposed and specified, and a prototype of it developed. The system is structured around three main components a database, a methods’ design base and the SPOP designer. This intervenes in the interaction between CADS-POMS design components and is fundamental for design activities too be carried. The methods used for supporting the design activities can be either resident in the CADS_POMS or accessed, via Internet for example, from distributed servers where they are implemented. Whenever there is a need for POMS design and quickly obtain POMS configurations solutions the system can be used. This promotes the frequent POMS design and reconfiguration process in order to improve the productivity of the industrial companies through better production systems