Production Lot Sizing Problem with the Lead Time

The issue in lot sizing problem is to plan production processes, so that mean the production quantities must be equal to customer demand quantities such that the inventory cost and setup production cost is minimized. In this work, we use the model Multi Level Capacitated Lot Sizing problem with consideration the Lead times, which means that the problem of finding a feasible solution is complex. For this, we propose a new formula in comparison with the classic model. The efficiency of the new formula is demonstrated and infeasible solutions are solved by a heuristic method that's based on Lagrangian relaxation. Computational tests conducted in 1000 instances with up to 40 components and 16 periods have shown that optimal solutions were obtained on average 96.43% of the large instances. For the improvement of the best solution, the heuristic is able to find the efficiency with 97.62% on average. The solution quality is evaluated through initial iterations, the average solution time provided by Lagrangian relaxation is less than 0.43s

A Distributed-Ledger, Edge-Computing Architecture for Automation and Computer Integration in Semiconductor Manufacturing

Contemporary 300mm semiconductor manufacturing systems have highly automated and digitalized cyber-physical integration. They suffer from the profound problems of integrating large, centralized legacy systems with small islands of automation. With the recent advances in disruptive technologies, semiconductor manufacturing has faced dramatic pressures to reengineer its automation and computer integrated systems. This paper proposes a Distributed- Ledger, Edge-Computing Architecture (DLECA) for automation and computer integration in semiconductor manufacturing. Based on distributed ledger and edge computing technologies, DLECA establishes a decentralized software framework where manufacturing data are stored in distributed ledgers and processed locally by executing smart contracts at the edge nodes. We adopt an important topic of automation and computer integration for semiconductor research & development (R&D) operations as the study vehicle to illustrate the operational structure and functionality, applications, and feasibility of the proposed DLECA software framewor

Analysis of production control methods for semiconductor research and development fabs using simulation

The importance of semiconductor device fabrication has been rising steadily over many years. Integrated circuit technology and innovation depends on successful research and development (R&D). R&D establishes the direction for prevailing technology in electronics and computers. To be a leader in the semiconductor industry, a company must bring technology to the market as soon as its application is deemed feasible. Using suitable production control methods for wafer fabrication in R&D fabs ensures reduction in cycle times and planned inventories, which in turn help to more quickly, transfer the new technology to the production fabs, where products are made on a commercial scale. This helps to minimize the time to market. The complex behavior of research fabs produces varying results when conventional production control methodologies are applied. Simulation modeling allows the study of the behavior of the research fab by providing statistical reports on performance measures. The goal of this research is to investigate production control methods in semiconductor R&D fabs. A representative R&D fab is modeled, where an appropriate production load is applied to the fab by using a representative product load. Simulation models are run with different levels of production volume, lot priorities, primary and secondary dispatching strategies and due date tightness as treatment combinations in a formally designed experiment. Fab performance is evaluated based on four performance measures, which include percent on time delivery, average cycle time, standard deviation of cycle time and average work-in-process. Statistical analyses are used to determine the best performing dispatching rules for given fab operating scenarios. Results indicate that the optimal combination of dispatching rules is dependent on specific fab characteristics. However, several dispatching rules are found to be robust across performance measures. A simulation study of the Semiconductor & Microsystems Fabrication Laboratory (SMFL) at the Rochester Institute of Technology (RIT) is used to verify the results

Modeling, design and scheduling of computer integrated manufacturing and demanufacturing systems

This doctoral dissertation work aims to provide a discrete-event system-based methodology for design, implementation, and operation of flexible and agile manufacturing and demanufacturing systems. After a review of the current academic and industrial activities in these fields, a Virtual Production Lines (VPLs) design methodology is proposed to facilitate a Manufacturing Execution System integrated with a shop floor system. A case study on a back-end semiconductor line is performed to demonstrate that the proposed methodology is effective to increase system throughput and decrease tardiness. An adaptive algorithm is proposed to deal with the machine failure and maintenance. To minimize the environmental impacts caused by end-of-life or faulty products, this research addresses the fundamental design and implementation issues of an integrated flexible demanufacturing system (IFDS). In virtue of the success of the VPL design and differences between disassembly and assembly, a systematic approach is developed for disassembly line design. This thesis presents a novel disassembly planning and demanufacturing scheduling method for such a system. Case studies on the disassembly of personal computers are performed illustrating how the proposed approaches work

A hybrid genetic approach to solve real make-to-order job shop scheduling problems

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro TecnologicoProcedimentos de busca local (ex. busca tabu) e algoritmos genéticos têm apresentado excelentes resultados em problemas clássicos de programação da produção em ambientes job shop. No entanto, estas abordagens apresentam pobres habilidades de modelamento e poucas aplicações com restrições de ambientes reais de produção têm sido publicadas. Além disto, os espaços de busca considerados nestas aplicações são nomlalmente incompletos e as restrições reais são poucas e dependentes do problema em questão. Este trabalho apresenta uma abordagem genética híbrida para resolver problemas de programação em ambientes job shop com grande número de restrições reais, tais como produtos com vários níveis de submontagem, planos de processamento altemativos para componentes e recursos alternativos para operações, exigência de vários recursos para executar uma operação (ex., máquina, ferramentas, operadores), calendários para todos os recursos, sobreposição de operações, restrições de disponibilidade de matéria-prima e componentes comprados de terceiros, e tempo de setup dependente da sequência de operações. A abordagem também considera funções de avaliação multiobjetivas. O sistema usa algoritmos modificados de geração de programação, que incorporam várias heurísticas de apoio à decisão, para obter um conjunto de soluções iniciais. Cada solução inicial é melhorada por um algoritmo de subida de encosta. Então, um algoritmo genético híbrido com procedimentos de busca local é aplicado ao conjunto inicial de soluções localmente ótimas. Ao utilizar técnicas de programação de alta perfomlance (heurísticas construtivas, procedimentos de busca local e algoritmos genéticos) em problemas reais de programação da produção, este trabalho reduziu o abismo existente entre a teoria e a prática da programação da produção

Tagungsband zum Doctoral Consortium der WI 2009

Bereits seit Anfang der 1990er Jahre wird jungen Wissenschaftlern im Vorfeld der Tagung Wirtschaftsinformatik ein Doctoral Consortium als unterstützendes Forum angeboten. Diese Einrichtung wurde auch zur größten internationalen Konferenz der Wirtschaftsinformatik, der WI 2009 in Wien fortgeführt. Dieser Band fasst die zum Vortrag ausgewählten Beiträge zusammen. Table of Contents: Tina Balke, On the Enforcement of Institutions for Reducing Uncertainty in Utility Computing Computational Economies …1; Christian Czarnecki, Gestaltung von Customer Relationship Management über die Grenzen von Telekommunikationsunternehmen hinweg …11; Christoph Danne, Assessing the cost of assortment complexity in consumer goods supply chains by reconfiguration of inventory and production planning parameters in response to assortment changes … 24; José M. González V., Gestaltung nachhaltiger IT-Landschaften in der Energiewirtschaft mit Hilfe von Referenzmodellen … 35; Christoph Habla, Eine Grobterminierungskomponente zur funktionalen Erweiterung von Manufacturing Execution Systems … 45; Frank Hogrebe, Integriertes Produkt- und Prozessmodell für die öffentliche Verwaltung … 55; Sebastian Hudert, A protocol-generic infrastructure for electronic SLA negotiations in the Internet of Services … 65; Bernd Jahn, Der Manager als Prosumer seines Unterstützungssystems - Ein Ansatz zum Entwurf Konfigurierbarer Managementunterstützungssysteme … 75; Florian Johannsen, Konzeption und Evaluation eines Ansatzes zur Methodenintegration im Qualitätsmanagement … 85; Karin Kronawitter, IT-Outsourcing in banking industry - stage of maturity model as strategic approach … 95; Barbara Krumay, Der Einuss von Online Kundenservice-Angeboten auf Kundenloyalität … 105; Tyge Kummer, Kulturelle Einflussfaktoren der Akzeptanz ambienter Systeme zur Vermeidung von Medikationsfehlern in Krankenhäusern … 115; Stefan König, Elektronische Verhandlungen im Internet-of-Services unter Berücksichtigung von Reputationsinformationen … 125; Tim Püschel, Intelligentes Ressourcenmanagement für Clouds - Konzept und Implementierung eines Entscheidungsmodells … 135; Olaf Reinhold, Auswirkungen auf die Gestaltung von CRM-Anwendungssystemen durch Kooperation von Unternehmen entlang von Wertschöpfungsketten und in Unternehmensnetzwerken … 144; Markus Ruch, Kundenindividuelle Steuerung von Transaktionsrisiken im E-Commerce … 155; Frank Schlosser, Die Bedeutung von operativem Business/IT-Alignment für nachhaltigen Unternehmenserfolg - Ein theoretisches Rahmenwerk und Richtlinien für die Praxis … 168; Christian Schultewolter, Konzeptuelle Modellierung für modellgetriebene Decision Support Systeme … 178; Gudrun Schütz, Preisstrategien von Internethändlern und deren technische Umsetzung … 188; Sarah Voltz, Prognose und Förderung des Verordnungsverhaltens von Ärzten in Netzwerkstrukturen … 198; -- Since the early 1990es, young researchers participate in the doctoral consortium series, co-located with the Wirtschaftsinformatik conference. This volume contains the selected papers of 20 PhD candidates of the 2009 doctoral consortium in Vienna.Wirtschaftsinformatik,Wirtschaftsinformatikstudium