Numerous aspects of job scheduling in manufacturing systems have been the focus of several studies in the past decades. However, human factors in manufacturing systems such as workers’ mental conditions are still neglected issues and have not received adequate attentions. Job boredom and mental fatigue are both aspects of workers’ mental condition. They affect work performances by increasing sick leave duration and decreasing work productivity. On the other hand, job rotation could be an alternative strategy to cope with such human issues at work. The benefits of job rotation for both employees and firms have been widely recognized in the literature. Although some studies found job rotation as a means to reduce workers' physical work-related traumas, they did not consider the effect of variable mental conditions on workers. Despite the proven importance of boredom and mental fatigue at the workplace, they have not been a combined precise objective of any job rotation problem in current literature. The study of mental conditions proposed in this paper attempts to extend the previous works by addressing new methods and developing a feasible solution to increase manufacturing productivity. A new job scheduling program has been designed specifically which combines a new job rotation model and a job assignment method.

From the earliest days of mass production in the automotive industry there has been a progressive move towards the use of flexible manufacturing systems that cater for product variants that meet market demands. In recent years this market has become more demanding with pressures from legislation, globalisation and increased customer expectations. This has lead to the current trends of mass customisation in production. In order to support this manufacturing systems are not only becoming more flexible† to cope with the increased product variants, but also more agile‡ such that they may respond more rapidly to market changes. Modularisation§ is widely used to increase the agility of automation systems, such that they may be more readily reconfigured¶. Also with globalisation into India and Asia semi-automatic machines (machines that interact with human operators) are more frequently used to reduce capital outlay and increase flexibility. There is an increasing need for tools and methodologies that support this in order to improve design robustness, reduce design time and gain a competitive edge in the market. The research presented in this thesis is built upon the work from COMPAG/COMPANION (COMponent- based Paradigm for AGile automation, and COmmon Model for PArtNers in automatION), and as part of the BDA (Business Driven Automation), SOCRADES (Service Oriented Cross-layer infrastructure for Distributed smart Embedded deviceS), and IMC-AESOP (ArchitecturE for Service- Oriented Process – monitoring and control) projects conducted at Loughborough University UK. This research details the design and implementation of a toolkit for building and simulating automation systems comprising components with behaviour described using Finite State Machines (FSM). The research focus is the development of the engineering toolkit that can support the automation system lifecycle from initial design through commissioning to maintenance and reconfiguration as well as the integration of a virtual human. This is achieved using a novel data structure that supports component definitions for control, simulation, maintenance and the novel integration of a virtual human into the automation system operation.

The present context and tendencies in modern production system, as mass customization, requires improvements with respect to the agility of the production organizations. In this sense, agile approaches have been proposed, such as the holonic approach. In Holonic Manufacturing System (HMS) the production entities, as resources and products, are envisaged with a type of intelligence. These smart-entities are called holons (HLs) whose intelligence is related to their autonomy and collaboration skills. The HMS also comprises a Holonic Control (HC) that must properly organize holon collaborations in order to become agile. Actually, HMS development requires engineering tools for design and testing. In this doctoral thesis, a meta-model for HC is proposed, whose instances are simulated within a particular tool called ANALYTICE II. This tool presents a clear separation between high-level control and emulated resources. Firstly, before the proposition of the HC meta-model, the resource holonification is proposed in this environment. Each Resource-HL is obtained by means of a virtual resource that provides data and services of an emulated-resource at a high level of control. Subsequently, the meta-model for HC over Resource-HLs following a process-driven production approach is proposed. The essence of the solution is based on Rule Base System (RBS) concepts being the causal relations of control dealt with by entities called Rules. The inference process in this RBS is realized through collaborations based upon notifications. The Resource-HLs notify the Rules about factual knowledge with respect to their states. Each Rule that is notified deliberates about the proper moment to execute some control action, as the coordination of a set of Resource-HLs, using causal knowledge. The inference occurs within a notification chain enabled by a group of Resource-HL agents and Rule agents. This kind of inference can be expected to provide advantages for the HC, such as high reactivity and entity decoupling. Furthermore, it allows for the creation of co-operative mechanisms for dealing with determinism and conflict issues. Moreover, this approach of rule-oriented control allows for coherent control implementation and expression. The control mechanisms emerge based on causal control knowledge expressed by experts in the Rules. Experts are exclusively concerned with the proper control knowledge needed for exploiting system flexibilities in order to increase system agility. Furthermore, some experts could even be artificial agents automatically dealing with knowledge of the Rules. Briefly, this process-driven HC solution concomitantly treats a set of control issues while also being a self-contained and open solution. Indeed, the solution openness allows its interpretation as a product-driven solution. The product-driven control is a tendency to reach agility by the decoupling of production demands and execution via entities like Smart-Product-HLs. Each Smart-Product-HL is concerned with a specific customized production order. The Smart-Product-HLs, with certain autonomy, use Resource-HLs to reach their production goals. In the meta-model interpretation, their interactions are organized by Rules for Resource-HL cooperation that avoids inappropriate system behavior. In this context, the execution of Rules depends upon the explicit Smart-Product-HL interest in their utilization. In some manner, each Smart-Product- HL deals with Rules as a kind of expert agent. The solution has been applied in a set of examples in ANALYTICE II presenting some simulation independence because each control instance is not aware that Resource-HLs and Smart-Product-HLs are simulated.

Orientador: Sergio Tonini Button / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-06T07:50:50Z (GMT). No. of bitstreams: 1 Nakayama_AlexandreYamassaki_M.pdf: 678284 bytes, checksum: fe25f524e1f87976fd997d7050c64bdb (MD5) Previous issue date: 2005 / Resumo: A competição cada vez mais acirrada do mundo globalizado exige das empresas o estudo e uso de ferramentas, teorias e conceitos que auxiliem no aumento de produtividade. Dentre os muitos sistemas administrativos e métodos de auxílio de aumento de produtividade, a Pesquisa Operacional tem se mostrado bastante eficiente e difundida pelos tomadores de decisões. Na Pesquisa Operacional, destacam-se especialmente as técnicas de Simulação e Programação Linear, técnicas que se desenvolveram em paralelo ao desenvolvimento da informática, esta tão presente no mundo atual. Este trabalho tem o objetivo principal de comparar a abordagem de um problema de programação da manufatura por estas técnicas distintas em um ambiente produtivo responsável pela fabricação de peças forjadas e usinadas para o setor automobilístico. O resultado esperado deste estudo é facilitar o entendimento e explicitar a diferença das duas técnicas englobando principalmente a aquisição e tratamento dos dados para uma escolha mais apurada / Abstract: The increasingly competitiveness in a globalization world demands from companies the study and use of tools, theories and concepts to provide productivity increase. Among the management tools and methods, the Operational Research has been largely diffused due to its efficiency. Especially emphasized are the Operational Research techniques of Simulation and Linear Programming that have been developed in parallel with Informatics. This research work has the main objective of comparing the application of both techniques in a manufacturing programming problem. The techniques were applied at a system responsible for manufacturing of components for the auto industry. The expected result of this study is to facilitate and explicitate the differences between the two techniques with approach to data acquisition and treatment and provide better information for a more accurate choice / Mestrado / Planejamento e Gestão Estrategica da Manufatura / Mestre em Engenharia Mecânica

No description available.

Numerous aspects of job scheduling in manufacturing systems have been the focus of several studies in the past decades. However, human factors in manufacturing systems such as workers’ mental conditions are still neglected issues and have not received adequate attentions. Job boredom and mental fatigue are both aspects of workers’ mental condition. They affect work performances by increasing sick leave duration and decreasing work productivity. On the other hand, job rotation could be an alternative strategy to cope with such human issues at work. The benefits of job rotation for both employees and firms have been widely recognized in the literature. Although some studies found job rotation as a means to reduce workers' physical work-related traumas, they did not consider the effect of variable mental conditions on workers. Despite the proven importance of boredom and mental fatigue at the workplace, they have not been a combined precise objective of any job rotation problem in current literature. The study of mental conditions proposed in this paper attempts to extend the previous works by addressing new methods and developing a feasible solution to increase manufacturing productivity. A new job scheduling program has been designed specifically which combines a new job rotation model and a job assignment method.

The thesis deals with planning and scheduling of production in the food industry. The theoretical part is concerned with the formulation and structure of the task scheduling and analyses the flow shop in the detail, for which a real application for an unnamed company has been created. It also briefly describes the technical specifications of production, which are crucial for the practical part. The practical part deals with the formulation of a mathematical model. The optimal solution is obtained using the optimization program MPL for Windows. Mathematical model includes variables that solves serial and parallel processors and try to capture as most exact as possible manufacturing processes with the technical specifications for a particular enterprise. The criterion for optimization is to minimize the cost in terms of the selected technology of production.

This thesis focuses on the analysis material flow of the production systemat Thermona Ltd. and suggestions for improvements. The work consists of theoretical, analytical and design parts. Thetheoretical part contains the basic concepts of production. In the analytical part, there is described a current situation in production area softhe company on the basis of theoretical knowledge. In the final part, the solutions are designed to help improve the business.

Market economic values have for the last decades been given an increasing role with the establishment of financial institutes and global organisations with a capitalistic focus as a consequence. As a counter reaction, the concept of sustainable development has emerged complementing the economic focus with environmental and social aspects. However, there are still challenges on how to make balanced decisions based on all three view points and consequently the decision makers still primarily reside to the established tangible financial data. Within the industrial setting there is no difference. The manufacturing system design is based on multiple criteria and requirements, but commonly the final investment decision is primarily based on what can be financially justified. Longterm solutions probably lies in combining the tangible economy with the less tangible soft values that cannot be valued in monetary means. Therefore, to find this sweet spot, the purpose of this research is to in-depth investigate the world of economy, but from an engineers' point of view. A financial analysis is done to understand the economical components and how these are related to the manufacturing system. Furthermore, to connect cost with contributed value of the manufacturing system, a holistic business value chain analysis is done to ensure that less tangible aspects can be understood and utilised. The result of this research, highlights for example that sales volume has a larger impact on the manufacturing profitability, than that of the initial investment cost. Therefore, manufacturing systems should also be evaluated on the bases of how well it can meet the volatility in market demands. Another result presented is a portfolio of new graphical representation used as a support tool for investment decisions. Furthermore, to be able to invest in manufacturing systems that contribute to a more competitive company, the wider business value with manufacturing is discussed.

With the advances in the information and computing technologies, the ways the manufacturing enterprise systems are being managed are changing. More integration and adoption of the system perspective push further towards a more flattened enterprise. This, in addition to the varying levels of aggregation and details and the presence of the continuous and discrete types of behavior, created serious challenges for the use of the existing simulation tools for simulating the modern manufacturing enterprise system. The commonly used discrete event simulation (DES) techniques face difficulties in modeling such integrated systems due to increased model complexity, the lack of data at the aggregate management levels, and the unsuitability of DES to model the financial sectors of the enterprise. System dynamics (SD) has been effective in providing the needs of top management levels but unsuccessful in offering the needed granularity at the detailed operational levels of the manufacturing system. On the other hand the existing hybrid continuous-discrete tools are based on certain assumptions that do not fit the requirements of the common decision making situations in the business systems. This research has identified a need for new simulation modeling approaches that responds to the changing business environments towards more integration and flattened enterprise systems. These tools should be able to develop comprehensive models that are inexpensive, scalable, and able to accommodate the continuous and discrete modes of behavior, the stochastic and deterministic natures of the various business units, and the detail complexity and dynamic complexity perspectives in decision making. The research proposes and develops a framework to combine and synchronize the SD and DES simulation paradigms to simulate the manufacturing enterprise system. The new approach can respond to the identified requirements in simulating the modern manufacturing enterprise systems. It is directed toward building comprehensive simulation models that can accommodate all management levels while explicitly recognizing the differences between them in terms of scope and frequency of decision making as well as the levels of details preferred and used at each level. This SDDES framework maintains the integrity of the two simulation paradigms and can use existing/legacy simulation models without requiring learning new simulation or computer programming skills. The new framework uses a modular structure by which the SD and DES models are treated as members of a comprehensive simulation. A new synchronization mechanism that that maintains the integrity of the two simulation paradigms and is not event-driven is utilized to coordinate the interactions between the simulation modules. It avoids having one simulation paradigm dominating the other. For communication and model management purposes the SDDES formalism provides a generic format to describe, specify, and document the simulation modules and the information sharing processes. The SDDES controller which is the communication manager, implements the synchronization mechanism and manages the simulation run ensuring correct exchange of data in terms of timeliness and format, between the modules. It also offers the user interface through which users interact with the simulation modules.