Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: Jonathan F. Bard. Vita. Includes bibliographical references.

In this dissertation, we consider two specific types of problems over networks. In the first problem, we explore systematic methods to address some of the challenges in largescale maintenance planning in integrated chemical sites. In the second problem, we investigate different optimization model formulations for the design of flow distribution networks where the flow is potential-driven and nonlinearly related to the potential loss. Maintenance turnaround in the processing industry is a complex asset renewal project that includes huge capital expenditures and downtime losses. The option of deferring or rescheduling a turnaround project typically provides immediate financial relief from capital expenditure. However, the risk of running into site-wide disruptions in the form of unplanned events, yield, and reliability losses is not straightforward to assess. We propose mathematical optimization models to evaluate the risk of loss from turnaround deferrals in integrated sites and provide alternatives to reliably operate the site in a medium-term horizon. In the first chapter, we introduce the turnaround planning problem and the challenges it poses in integrated sites. We also introduce the background for the network design problem. In the second chapter, we study the financial impact of rescheduling turnarounds and the associated risk under unplanned outages. We compare the risk profiles presented by different production planning strategies. We propose a stochastic programming model for production planning that optimally builds up inventory ahead of time to hedge against production losses during unplanned outages. In the third chapter, we extend the stochastic optimization to handle a large set of scenarios and propose a Lagrangean decomposition method that improves a myopic production plan. The fourth chapter proposes a mixed-integer linear programming model that prescribes turnaround schedules when the underlying assets undergo yield loses and selectivity degradation. Here, we also study the impact of deferrals over a long-term horizon. The penultimate chapter addresses the nonlinear network design problem.The closing chapter summarizes the work and provides a few future directions. In the spirit of advancing manufacturing paradigms, the thesis supports investment in modeling efforts that address enterprise-wide planning problems.

A software agents based manufacturing scheduling module for Advanced Planning and Scheduling (APS) is presented. The problem considered is scheduling of jobs with multiple operations, distinct operation processing times, arrival times, and due dates in a job shop environment. Sequence dependent setups are also considered. The additional constraints of material and resource availability are also taken into consideration. The scheduling is to be considered in integration with production planning. The production plans can be changed dynamically and the schedule is to be generated to reflect the appropriate changes. The design of a generic multi-agent framework which is domain independent along with algorithms that are used by the agents is also discussed. / Master of Science

Esta dissertação tem como finalidade analisar a implantação de sistemas APS em empresas sob a perspectiva de redes de inovação auto-organizadas. Considera-se que a implantação do sistema APS representa uma inovação organizacional para a área de planejamento e controle da produção da empresa adquirente do software, pois comparado aos sistemas de planejamento e controle da produção predecessores, supre deficiências referentes às limitações de capacidade da empresa, flexibilidade na geração de estratégias de produção, disponibilização de prazos de entrega mais curtos e maior apoio aos processos de decisão. Considera-se também que o processo de implantação pode ser analisado sob a perspectiva de uma rede auto-organizada, formada pela empresa adquirente, implantadora e desenvolvedora do software, o que permite identificar os nós (empresas), ligações (relacionamentos), posições (atividades das empresas), fluxos tangíveis (recursos físicos) e fluxos intangíveis (troca de conhecimento e informações). A metodologia de pesquisa utilizada compreende um estudo bibliográfico para o embasamento teórico da temática proposta e de sete estudos de caso para a coleta de dados em campo. A análise e discussão do cruzamento entre as evidências teóricas e práticas visa identificar e sistematizar elementos para disponibilizar um modelo de referência para a implantação de sistemas APS. O desenvolvimento do modelo de referência foi orientado pela metodologia Enterprise Knowledge Development (EKD), e o mesmo foi avaliado por profissionais de empresas implantadoras e pesquisadores acadêmicos, a fim de verificar sua consistência e identificar possíveis melhorias. / This dissertation aims to analyze the APS systems implementation in companies under the selforganizing innovation networks perspective. It is considered that the APS systems implementation represents an organizational innovation in the area of production planning and control of the software\'s acquiring company, because compared to the predecessors production planning and control systems, supplies deficiencies relating to capacity constraints of the company, flexibility in the generation of production strategies and greater support to decisionmaking. It is also considered that the implementation process can be analyzed under the perspective of a self-organized network formed by the acquirer, implanter and developer companies of the software, which allows us to identify the nodes (companies), links (relationships), positions (activities of companies), tangible flows (physical resources) and intangible flows (exchange of knowledge and information). The research methodology used comprises a bibliographical study to the theoretical background of the proposed theme and seven case studies to data collection in the field. The analysis and discussion of the intersection between theoretical and practical evidences aims to identify and systematize elements for provide a reference model for the APS systems implementation. The development of the reference model was guided by the Enterprise Knowledge Development (EKD) methodology, and the model was assessed by implementing companies professionals and academic researchers in order to check its consistency and identify possible improvements.

Esta dissertação tem como finalidade analisar a implantação de sistemas APS em empresas sob a perspectiva de redes de inovação auto-organizadas. Considera-se que a implantação do sistema APS representa uma inovação organizacional para a área de planejamento e controle da produção da empresa adquirente do software, pois comparado aos sistemas de planejamento e controle da produção predecessores, supre deficiências referentes às limitações de capacidade da empresa, flexibilidade na geração de estratégias de produção, disponibilização de prazos de entrega mais curtos e maior apoio aos processos de decisão. Considera-se também que o processo de implantação pode ser analisado sob a perspectiva de uma rede auto-organizada, formada pela empresa adquirente, implantadora e desenvolvedora do software, o que permite identificar os nós (empresas), ligações (relacionamentos), posições (atividades das empresas), fluxos tangíveis (recursos físicos) e fluxos intangíveis (troca de conhecimento e informações). A metodologia de pesquisa utilizada compreende um estudo bibliográfico para o embasamento teórico da temática proposta e de sete estudos de caso para a coleta de dados em campo. A análise e discussão do cruzamento entre as evidências teóricas e práticas visa identificar e sistematizar elementos para disponibilizar um modelo de referência para a implantação de sistemas APS. O desenvolvimento do modelo de referência foi orientado pela metodologia Enterprise Knowledge Development (EKD), e o mesmo foi avaliado por profissionais de empresas implantadoras e pesquisadores acadêmicos, a fim de verificar sua consistência e identificar possíveis melhorias. / This dissertation aims to analyze the APS systems implementation in companies under the selforganizing innovation networks perspective. It is considered that the APS systems implementation represents an organizational innovation in the area of production planning and control of the software\'s acquiring company, because compared to the predecessors production planning and control systems, supplies deficiencies relating to capacity constraints of the company, flexibility in the generation of production strategies and greater support to decisionmaking. It is also considered that the implementation process can be analyzed under the perspective of a self-organized network formed by the acquirer, implanter and developer companies of the software, which allows us to identify the nodes (companies), links (relationships), positions (activities of companies), tangible flows (physical resources) and intangible flows (exchange of knowledge and information). The research methodology used comprises a bibliographical study to the theoretical background of the proposed theme and seven case studies to data collection in the field. The analysis and discussion of the intersection between theoretical and practical evidences aims to identify and systematize elements for provide a reference model for the APS systems implementation. The development of the reference model was guided by the Enterprise Knowledge Development (EKD) methodology, and the model was assessed by implementing companies professionals and academic researchers in order to check its consistency and identify possible improvements.

This diploma thesis is focused on process of production planning and scheduling in company Meopta – optics, Ltd., in connection with the possibility of its optimization. The basis of the thesis is analysis of the current status of planning and production management, evaluation of theoretical approaches dealing with issues of production planning and solution proposal optimizing the existing processes. The diploma thesis was elaborated with the support of Head of operative planning in Meopta - Optics Ltd.

The construction industry suffers from many practical problems and challenges; most being related to construction management. One of the most common recurring problems in construction projects is delay. Delay is a primary factor that can have an effect on project duration, scheduled delivery date, as well as the overhead cost of the project. This study investigated the problem of delays in construction projects. The research focused on the combination of Building Information Modeling (BIM) and Last Planner System (LPS) together to measure the execution time of construction projects. The aim of this study was to determine whether using BIM and LPS together affect construction process delay differently than using BIM or LPS alone. The methodology of this study relied on data collection through administration of survey questionnaires to key players and participants at construction companies. Interviews were conducted with construction experts from four construction companies that used BIM and LPS individually in their system as case studies to verify and validate the findings. The outcomes of this survey will be helpful to construction practitioners to reduce delay in construction operations and to shorten projects duration.

Thesis (Ph. D.)--Ohio State University, 1984. / Includes bibliographical references (leaves 171-177). Available online via OhioLINK's ETD Center.

Semiconduct industry is facing the various supply chain uncertainty problems at present. MRP/ERP (Material Resource Planning/Enterprise Resource Planning) solution can¡¦t satidfy the requirement of production planning and scheduling for the enterprise. In this research¡Aon APS (Advanced Planning & Scheduling) system was proposed for an IC (Intergrated Circuit) substrate industry to replace manual planning process and to solve the resource constraint problems of production. Following topics was addressed :

The planning and scheduling requirement of industry can not be satisfied by traditional scheduling systems. Companies need to put extra human resource to fix the result made by these systems. The main reason is an improper assumption of infinite capacity adopted by these scheduling systems. In order to improve the scheduling result, this research refers plastic injection industry¡¦s characters to implement a decision support system. The decision support system integrates Forward Finite Loading and Constraint Directed into our algorithm in order to minimize the increase in total cost, and raise the capacity balance between machines .According to the result of the practical research, we can prove this decision support system is more effective and efficiency than the traditional scheduling method.