Project/Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1992. / Vita. Includes bibliographical references (leaf 21). Also available via the Internet.

Project report (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 97-98). Also available via the Internet.

Project report (M. Eng.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaf 114). Also available via the Internet.

Approved for public release; distribution is unlimited / The purpose of this thesis is to analyze the relationship between predicted system reliability and planned spare parts levels. This will be accomplished through the integration of factors impacting spare parts levels and Life Cycle Costs into a spreadsheet model that will establish the appropriate relationship between the factors. This thesis will then attempt to determine the impact that varying estimations of reliability will have on both Life Cycle Costs nd spares levels for the H-1 Upgrades Program. / Major, United States Marine Corps

Thesis (M.S. in Management)--Naval Postgraduate School, June 2004. / Thesis advisor(s): Don Eaton. Includes bibliographical references (p. 97-98). Also available online.

First, we consider a fundamental pricing model for a single type of reusable resource in which a fixed number of units are used to serve stochastically arriving customers. Customers choose to purchase the resource based on their willingness-to-pay and the current price. If purchased, occupy one unit of the reusable resources for a random amount of time. The firm seeks to maximize a weighted combination of profit, market share, and service level. We establish a series of theoretical results that characterize the strong universal performance of static pricing in such an environment. Second, we describe a comprehensive approach to pricing analytics for reusable resources in the context of rotable spare parts with an industrial partner. We discuss the process of instilling a new pricing culture and developing a scalable new pricing methodology at a major aircraft manufacturer. We develop a novel pricing analytics approach for all rotable spare parts. The new approach tackles the challenges of limited data availability, minimal demand information, and complex inventory dynamics. We also present a successful large-scale implementation of our approach which led to significant profit gains. Third, we extend the pricing model for reusable resources to the setting of multiple customer classes. We describe two types of heuristics for this class of problem with accompanying numerical experiments. In addition, we provide a universal performance guarantee for a special case. We also discuss the role of substitution effects between different classes of customers.

<p>This report focused on the suboptimization of a logistics support system that is assumed to be in existence. A minimum steady-state level of spares was sought to meet a demand due to the discarding of failed items.</p> / Master of Science

<p>During the early stages of the acquisition cycle for a military equipment, the question arises as to how the system will be maintained at an operationally capable level. The desired level of readiness must be balanced against the cost of system maintenance. The primary question to be answered is what is the optimum (i.e., least cost) maintenance concept which will allow the system to meet its specified performance goals. In order to answer this question, one must compare the costs associated with the possible choices in maintenance alternatives.</p> <p> Level of Repair Analysis, or LORA for short, is an optimization technique used to determine the optimum level of repair for each component in the system. Premised on accurately addressing selected system life-cycle maintenance costs, the methodology, data requirements, and algorithms used to conduct a LORA are found in Military Standard 1390C, Level of Repair Analysis.</p> <p> LORA examines the feasibility of repair from both technical (non-economic) and economic standpoints. The optimization process will determine whether it is feasible to repair an item, and if so, where and how. While LORA is an excellent and necessary tool, like many analyses of its type, it has limitations. Like any analytical tool, one must understand both the strengths and weaknesses of the process to properly apply its techniques and interpret its results. Data collection and entry into a computer model can be made relatively easily. Paramount however to properly applying the techniques and results is a thorough understanding of the LORA process. Therefore, the primary focus of this project and report is to illustrate the strengths and limitations of the WRA process by its application to a specific example. It is not intended to pass judgement on the LORA process as implemented and utilized by DOD. Rather, it is intended that this report present an overview of the LORA process and detail some of the nuances one could expect to encounter when performing a LORA.</p> <p> This report contains a description of the Level of Repair Analysis process and how this process was applied to a specific United States Department of Defense electronics system. This report documents the analysis (data and calculations used) to reach the repair and discard decisions for the NIXIE Signal Generator Engineering Change Kit for the AN/SLQ-25, a US Navy electronics equipment. This report differs from the one submitted under the contract in that it contains more theoretical detail on the overall LORA process and does not include any classified or proprietary data.</p> / Master of Engineering

Submitted by HENRIQUE KRIGUER (henriquekriguer@uol.com.br) on 2016-02-15T11:56:47Z No. of bitstreams: 1 Dissertação de Mestrado Henrique Kriguer 2015 corrigido após qualificação.pdf: 1729817 bytes, checksum: 2ab0f19734b9d93a734ea53248959168 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-02-15T12:20:05Z (GMT) No. of bitstreams: 1 kriguer_h_me_guara.pdf: 1729817 bytes, checksum: 2ab0f19734b9d93a734ea53248959168 (MD5) / Made available in DSpace on 2016-02-15T12:20:05Z (GMT). No. of bitstreams: 1 kriguer_h_me_guara.pdf: 1729817 bytes, checksum: 2ab0f19734b9d93a734ea53248959168 (MD5) Previous issue date: 2015-12-21 / O gerenciamento de estoques torna-se cada vez mais importante em função da necessidade de aperfeiçoamento da eficiência na cadeia logística, que se traduz na redução de custos e aumento do nível de serviço. A literatura sobre o gerenciamento de estoques de peças de reposição é ampla, porém é pouco abordada em relação à escolha do modelo de classificação. Neste trabalho, o método Analytic Hierarchy Process (AHP) foi aplicado em uma Empresa de bens de capital para determinar o vetor de prioridade dos critérios adotados para a classificação de peças de reposição. Apresentamos, com base no resultado deste estudo o Índice de Reposição, que foi adotado como um fator de correção nos valores de estoque segundo a classificação ABC. O objetivo foi atingido com o aperfeiçoamento do método de classificação, tornando o trabalho do planejador de estoques melhor estruturado, permitindo que possa tomar a decisão de reabastecimento de forma estruturada conforme parâmetros pré estabelecidos. / The inventory management becomes increasingly important due to the need for improved efficiency in the supply chain, which translates into cost savings and increased service level. The literature on the management of spare parts inventory is wide, but is rarely addressed in relation to the choice of classification model. In this work, the Analytic Hierarchy Process (AHP) method was applied to a Company of capital goods to determine the priority vector of the criteria adopted for the spare parts classification. Here, based on the results of this study the Replacement Index, which was adopted as a correction factor in inventory values according to the ABC classification. The goal was achieved with the improvement of classification method, making the work of the best structured inventory planner, allowing can take the form of structured replenishment decision as pre-established parameters

Denna studie är en kvantitativ studie som syftar till att undersöka sambandet mellan tillgängligheten av reservdelar och maskinprestanda. Litografi och plasma är Silexs två produktionsstationer som undersöks i denna studie. Det analyseras data över en tre månaders period för att undersöka sambandet mellan reservdelskostnader och maskinernas drifttid. Metoden innefattar en kvantitativ analys av reservdelslager, maskinprestanda och rapporterade maskintillstånd. Statistiska verktyg används för att identifiera korrelationer. Resultaten visade att det finns en koppling mellan tillgängligheten av reservdelar och deras förbrukning, eftersom de maskiner som hade flest reservdelar på lager också gjorde flest uttag av reservdelar under underhåll. I Litografi fanns det en komplex korrelation: vissa maskiner visade en negativ korrelation mellan kostnad och prestanda eftersom de inte hade tillräckligt med reservdelar på lagret, medan andra maskiner visade en positiv korrelation, vilket tyder på att tillgängliga reservdelar förkortade drifttiden. Plasma-arean visade en positiv korrelation mellan reservdelskostnader och drifttid. Trots detta uppstod begränsningar för kapitalbindning och lagerutrymme som ett resultat av en överrepresentation av långsamtgående reservdelar i lagret. Slutsatsen är att det finns ett samband mellan maskinprestanda och tillgången på reservdelar, och att en balanserad tillgång till kritiska reservdelar är avgörande för att optimera driften. Förbättringar som skulle kunna göras inkluderar att standardisera rapporteringstekniker, skapa ett säkerhetslager för varje maskin. För att analysera slow-mover-reservdelar och göra en ekonomisk jämförelse mellan SLA-täckta och lagerreservdelar krävs ytterligare forskning. / This study is a quantitative analysis that aims to explore the link between spare parts availability and machine performance. The two production lines examined in this study are lithography and plasma at Silex. Data spanning a three-month period is analyzed to examine the correlation between spare parts costs and machine uptime. The methodology involves a quantitative analysis of spare parts stocks, machine performance, and reported machine conditions. Statistical tools are used to identify correlations. The results showed a correlation between spare parts availability and consumption, as machines with the highest spare parts stocks also made the most withdrawals during maintenance. In lithography, a complex correlation was observed: some machines showed a negative correlation between spareparts cost and machine performance due to insufficient spare parts stock, while others showed a positive correlation, suggesting that available spare parts shortened downtime. The plasma area showed a positive correlation between spare parts costs and uptime. However, limitations arose in terms of capital tied up and storage space due to an over-representation of slow-moving spare parts in the stock. The conclusion indicates a correlation between machine performance and the availability of spare parts, emphasizing that a balanced supply of critical spare parts is essential for optimizing operations. Suggested improvements include standardizing reporting techniques and creating a safety stock for each machine. Further research is needed to analyze slow-moving spare parts and make an economic comparison between SLA-covered and stock spare parts.