In this thesis, two systems are analyzed in order to gain insight to the following issues: (i) Effect of incentive, subsidy and penalty designs on decentralized system, (ii) effect of using production facility as pooled capacity (pooled system) and dedicated capacity (unpooled system) on capacity utilization and system profit. Regarding the first issue, three models are defined / decentralized model, centralized model and decentralized model with incentive, subsidy, penalty designs. In all models, there are two dealers and one item is under consideration and lateral transshipments are allowed. Dealers operate with four inventory level decision (strategies) that consists of base stock level, rationing level, transshipment request level and customer rejection level. Under the decentralized system, a dealer sets its operating strategy according to the strategy of the other dealer and maximizes its own infinite horizon discounted expected profit. In the centralized system, a central authority (say manufacturer) exists, which considers the system-wide infinite horizon discounted expected profit, and makes all decisions. Under decentralized system with incentive, subsidy, penalty designs, manufacturer tries different designs on decentralized system namely revenue sharing, holding cost subsidy, request rejection penalty, transportation cost subsidy and commission subsidy in order to v align decentralized system with centralized system. According to the results obtained, this alignment works best with nearly 40% revenue sharing percentage, low rejection penalty, high transportation cost subsidy under low transportation cost and commission subsidy under very low or very high commissions. Holding cost subsidy, on the other hand, is not a good strategy since it declines decentralized system profit. Considering the second issue, two systems are examined / pooled system and unpooled system. Both systems are centrally managed. In the pooled system, all capacity is dynamically allocated to either dealer considering maximization of system profit. In the unpooled system, capacity is shared among dealers and dealers are always allocated same percentage of the capacity. Infinite horizon average expected profit is maximized in both systems. The dealer having lower holding cost is allocated higher capacity in both pooled and unpooled system / however, exceptions exist in the unpooled system under low arrival rate. Highrevenue dealer is always allocated higher capacity in both pooled and unpooled system. Arrival rate affects both systems such that total capacity utilization increases with increasing arrival rate. From the profit point of view, pooled system has great advantage under low demand rate in general.

We propose a mathematical framework that integrates low-level sensory signals from monitoring engineering systems and their components with high-level decision models for maintenance optimization. Our objective is to derive optimal adaptive maintenance strategies that capitalize on condition monitoring information to update maintenance actions based upon the current state of health of the system. We refer to this sensor-based decision methodology as "sense-and-respond logistics". As a first step, we develop and extend degradation models to compute and periodically update the remaining life distribution of fielded components using in situ degradation signals. Next, we integrate these sensory updated remaining life distributions with maintenance decision models to; (1) determine, in real-time, the optimal time to replace a component such that the lost opportunity costs due to early replacements are minimized and system utilization is increased, and (2) sequentially determine the optimal time to order a spare part such that inventory holding costs are minimized while preventing stock outs. Lastly, we integrate the proposed degradation model with Markov process models to derive structured replacement and spare parts ordering policies. In particular, we show that the optimal maintenance policy for our problem setting is a monotonically non-decreasing control limit type policy. We validate our methodology using real-world data from monitoring a piece of rotating machinery using vibration accelerometers. We also demonstrate that the proposed sense-and-respond decision methodology results in better decisions and reduced costs compared to other traditional approaches.

We consider a single-part, two-echelon supply chain problem for spare parts. The network consists of a single manufacturing plant, a set of service centers (SCs) and a set of customers. Both echelons keep spare parts using the base-stock replenishment policy. The plant behaves as an M/M/1 queueing system and has limited production and storage capacity. Demand faced by each SC follows an independent Poisson process. The problem is to determine optimal location-allocation and optimal base-stock levels at both echelons while satisfying the target service levels and customer preferences of SCs. We develop a mixed integer non-linear programming model and use cutting-plane method to optimize the inventory-location decisions. We present an exact solution procedure for the inventory stocking problem and demonstrate the limitations of using traditional inventory models like METRIC-like and Approximate in case of high utilization rates. We show the effectiveness of our proposed cutting-plane algorithm and provide important managerial insights for spare parts management.

Organizations are expected by their shareholders to continually deliver above industry returns on capital invested and to remain competitive in the industry of choice through productivity, safety and quality. The maintenance function is a key area in which competitiveness through efficiencies and world–class performance can be attained by focusing on the prevention and reduction of long and costly equipment repair times. The question is: how can the mean time to repair of equipment already installed in the plant be reduced? To answer the above question correctly and comprehensively, the research explored mixed methods in finding answers. Quantitative methodology using a survey was used for data collection. Observations and interviews were held with maintenance personnel to uncover information that couldn’t have been obtained by means of a survey. The survey was limited to equipment performance measures, human factors, environmental factors, planning, spare parts, maintainability, procedures and training. To test consistency and accuracy of representation of the total population under study, a reliability test was done by using Cronbach’s alpha coefficient. To determine whether there are any differences between groups, an ANOVA test was used. Cohen’s d–value was used to determine practically significant differences between one set of data with another and correlation analysis was used to determine the relationships between the variables. The approach designed and delivered by this research flowed from the existing body of knowledge, case studies and survey findings. The approach adopts some of the elements of the failure mode and effects analysis (FMEA) procedure and differs from other work that has been done by others by taking into account the competency and experience of maintenance personnel and assigning to them factors which are used to compute anew MTTR of the equipment. The cost of implementing the recommended corrective actions for realising the new MTTR is determined and evaluated against an improved equipment availability that will be achieved as a result of the recommended corrective actions assuming that the failure rate of the equipment remains constant. This evaluation step imbedded within the approach is valuable for the maintenance function and management for decision making in ensuring that resources at the organization’s disposal are used productively. Validation and test results of the approach showed that the MTTR of equipment installed in the plant can be reduced. The results also indicated that through the use of the designed approach a regular pattern of repair or replacement times can be followed well in advance and that it is practical, user friendly and it also delivers on its objective of offering a structure for analysis and decision making aimed at reducing the MTTR. Included with this dissertation is feedback information that can be included in a maintenance job card feedback section to capture information about factors that can be improved to lower the MTTR as part of a continuous improvement process. Included also is a spare part development and management procedure that can be used by the maintenance function. Recommendations on training of maintenance personnel on the maintainability of equipment, the FMEA procedure and maintenance procedures are highlighted. Information that flowed from this approach will be valuable for continuous plant performance improvement and during the design, installation and operation stages of a blast furnace. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2012.

Organizations are expected by their shareholders to continually deliver above industry returns on capital invested and to remain competitive in the industry of choice through productivity, safety and quality. The maintenance function is a key area in which competitiveness through efficiencies and world–class performance can be attained by focusing on the prevention and reduction of long and costly equipment repair times. The question is: how can the mean time to repair of equipment already installed in the plant be reduced? To answer the above question correctly and comprehensively, the research explored mixed methods in finding answers. Quantitative methodology using a survey was used for data collection. Observations and interviews were held with maintenance personnel to uncover information that couldn’t have been obtained by means of a survey. The survey was limited to equipment performance measures, human factors, environmental factors, planning, spare parts, maintainability, procedures and training. To test consistency and accuracy of representation of the total population under study, a reliability test was done by using Cronbach’s alpha coefficient. To determine whether there are any differences between groups, an ANOVA test was used. Cohen’s d–value was used to determine practically significant differences between one set of data with another and correlation analysis was used to determine the relationships between the variables. The approach designed and delivered by this research flowed from the existing body of knowledge, case studies and survey findings. The approach adopts some of the elements of the failure mode and effects analysis (FMEA) procedure and differs from other work that has been done by others by taking into account the competency and experience of maintenance personnel and assigning to them factors which are used to compute anew MTTR of the equipment. The cost of implementing the recommended corrective actions for realising the new MTTR is determined and evaluated against an improved equipment availability that will be achieved as a result of the recommended corrective actions assuming that the failure rate of the equipment remains constant. This evaluation step imbedded within the approach is valuable for the maintenance function and management for decision making in ensuring that resources at the organization’s disposal are used productively. Validation and test results of the approach showed that the MTTR of equipment installed in the plant can be reduced. The results also indicated that through the use of the designed approach a regular pattern of repair or replacement times can be followed well in advance and that it is practical, user friendly and it also delivers on its objective of offering a structure for analysis and decision making aimed at reducing the MTTR. Included with this dissertation is feedback information that can be included in a maintenance job card feedback section to capture information about factors that can be improved to lower the MTTR as part of a continuous improvement process. Included also is a spare part development and management procedure that can be used by the maintenance function. Recommendations on training of maintenance personnel on the maintainability of equipment, the FMEA procedure and maintenance procedures are highlighted. Information that flowed from this approach will be valuable for continuous plant performance improvement and during the design, installation and operation stages of a blast furnace. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2012.

[pt] Atualmente, muitas organizações visam satisfazer as necessidades de clientes eliminando custos. Novas soluções inovadoras são adotadas para incrementar a eficiência da Logística, e em paralelo, reduzir custos operacionais com a utilização de Tecnologia da Informação (TI). A RFID (identificação por radiofrequência) é a TI que proporciona o incremento da integração, da eficiência e da eficácia em toda a cadeia analisada. Embora existam desafios afiançados para a implementação da tecnologia em materiais metálicos, há aplicações desenvolvidas neste nicho, incluindo pesquisas subsidiadas pela Marinha Americana. Benefícios e vantagens da RFID são expostos: incremento da precisão do inventário, redução do custo da mão de obra, mitigação de erros de registro, incremento dos níveis de serviço, aumento da integração e monitoramento de processos logísticos à jusante da cadeia. Neste contexto, este trabalho tem por objetivos analisar a viabilidade de implantação da tecnologia RFID nas Fragatas Classe Niterói - FCN, conservada a compatibilidade com os sistemas correntes, discorrendo as oportunidades contemporâneas, vantagens e benefícios da tecnologia orientada ao incremento da eficiência na cadeia de suprimentos de sobressalentes das FCN; evidenciar o ganho em custo de mão de obra nas operações de armazenagem e o incremento da precisão de inventário; e avaliar os requisitos técnicos e econômicos para a adoção da RFID nas FCN. Conclui-se que o modelo futuro com a RFID é viável e gera Retorno sobre Investimento - ROI de 2,24 utilizando apenas como benefício à redução do custo de mão de obra. Outros benefícios com base em benchmarking são evidenciados. / [en] Currently, many organizations seek to satisfy the needs of customers by eliminating costs. New innovative solutions are adopted to improve the efficiency of Logistics, and in parallel, reduce operational costs with the adoption of Information Technology (IT). RFID (radio frequency identification) is the IT that provides the improvement of integration, efficiency and effectiveness throughout the chain analyzed. Although there are challenges bailed by the technology implementation in metallic materials, there are applications developed on this niche, including researches subsidized by the U.S. Navy. Benefits and advantages of RFID are exposed: improvement of the inventory accuracy, reduction of the cost of labor, mitigation of registry errors, increase service levels, increase of the integration and of logistics processes monitoring towards the downstream chain. In this context, this paper aims to analyze the feasibility of RFID deployment technology in the Niterói Class Frigates - FCN, preserving the compatibility with the current systems, discussing contemporary opportunities, advantages and benefits of technology oriented to increase the efficiency of the FCN spare parts supply chain; show the gain in the cost of labors in warehouse operations and the improvement of the inventory accuracy; and evaluate the technical and economical requirements for the adoption of RFID in the FCN. We conclude that the future model with RFID is feasible and generate Return on Investment (ROI) of 2.24 using only as benefit the decreasing labor cost. Other benefits based on benchmarking are highlighted.

Made available in DSpace on 2014-12-17T14:52:58Z (GMT). No. of bitstreams: 1 RobertoKMF_DISSERT.pdf: 1712911 bytes, checksum: 4a2d9da3d58d19eb0b246c2f5c1cf027 (MD5) Previous issue date: 2010-12-22 / This work searches to offer a model to improve spare parts stock management for companies of urban passenger transport by bus, with the consequent progress in their maintenance management. Also known as MRO items (Maintenance, Repair and Operations), these spare parts, according their consumption and demand features, cost, criticity to operation, lead-time, quantity of suppliers, among other parameters, shouldn?t have managed their inventory like normal production items (work in process e final products), that because their features, are managed by more predictable models based, for example, in economic order quantity. In the case specifically of companies of urban passenger transport by bus, items MRO have significant importance in their assets and a bad management of these inventories can cause serious losses to company, leading it even bankrupticy business, in more severe situations which missing spare part provokes vehicles shutdown indefinitely. Given slight attention to the issue, which translates in little literature available about it when compared to that literature about normal items stocks, and due the fact that MRO items be critical to bus urban transport of passengers companies?, it is necessary, so, deepen in this theme searching to give technical and scientific subsidies to companies that work, in many times, empirically, with these so decisive inputs to their business. As a typical portfolio problem, in which there are n items, separated into critical and noncritical, while competing for the same resource, it was developed a new algorithm to aid in a better inventory management of spare parts used only in corrective maintenance (whose failures are unpredictable and random), by analyzing the cost-benefit ratio, which compares the level of service versus cost of each item. The model was tested in a company of urban passenger transport by bus from the city of Natal, who anonymously provided their real data to application in this work / O trabalho busca oferecer um modelo para melhor gest?o do estoque de pe?as de reposi??o para empresas de transporte urbano de passageiros, com a conseq?ente melhoria na gest?o das suas manuten??es. Tamb?m conhecidos como itens MRO (Manuten??o, Reparo e Opera??es), estas pe?as de reposi??o, em fun??o das suas caracter?sticas de consumo e demanda, custo, criticidade para a opera??o, tempo de ressuprimento, quantidade de fornecedores, entre outros par?metros, n?o devem ter seus estoques geridos como itens normais de produ??o (bens intermedi?rios e produtos acabados), que pelas suas caracter?sticas, s?o regidos por modelos mais previs?veis baseados, por exemplo, no lote econ?mico de compra. Em se tratando especificamente de empresa de transporte urbano de passageiros por ?nibus, os itens MRO t?m peso significativo nos seus ativos e a m? gest?o deste estoque pode causar s?rios preju?zos ? companhia, levando-a, em situa??es mais graves em que a pe?a faltante resulte em parada de ve?culos por tempo indeterminado, at? ? fal?ncia do neg?cio. Face ? discreta aten??o ao tema, o que se traduz na pouca literatura dispon?vel sobre o mesmo quando comparada ?quela relacionada aos estoques de itens de produ??o, e devido ao fato dos itens MRO serem cr?ticos para as empresas de transporte urbano de passageiros, faz-se necess?rio, pois, o aprofundamento no assunto buscando dar subs?dios t?cnico-cient?ficos ?s firmas que trabalham, muitas vezes de forma emp?rica, com estes insumos t?o decisivos para o seu neg?cio. Tendo-se um t?pico problema de portf?lio, no qual existem n itens, segregados em cr?ticos e n?o-cr?ticos, competindo simultaneamente pelo mesmo recurso, foi desenvolvido um novo algoritmo para auxiliar na melhor gest?o do estoque de pe?as de reposi??o utilizadas somente em manuten??es corretivas (cujas falhas s?o imprevis?veis e aleat?rias), atrav?s da an?lise da rela??o custo-benef?cio, onde comparam-se n?vel de servi?o versus custo de cada item. O modelo foi testado em uma empresa de transporte urbano de passageiros por ?nibus da cidade de Natal, que anonimamente, forneceu seus dados reais para aplica??o neste trabalho

The operation and maintenance phase of a complex technical system may deal with strategicdecisions for asset retirement and end-of-life management. When a fleet of aircraft reachesthe retirement phase, the operation of remaining fleet should still be kept at a defined level ofavailability. Obviously, the provisioning of spares is a key issue to support the maintenanceand operation of the remaining fleet. The best practice within the aviation industry is to re-usethe spares of retired aircraft to support the operational fleet. This is referred to parting-out.The purpose of the research conducted for this thesis has been to develop decision supportmethodologies, models and tools for the management of a sustainable part-out-based sparesprovisioning for an aircraft fleet during its retirement period. The proposed methodology willbe used to support the retirement process of aircraft fleet and enhance the organisation’scapability of making efficient and cost-effective decisions concerning the re-use of spare partsduring the retirement period. To achieve the purpose of this research, literature studies, casestudies, algorithm development and simulations have been conducted. Empirical data havebeen collected through document studies, interviews, and the perusal of archival records fromSaab Support and Services AB. The data analysis performed for this research has been basedon theories and methodologies within reliability analysis, cost modelling, spares forecasting,stock provisioning and decision making, in combination with the best practices implementedby the aviation industry for the end-of-life management and retirement of aircraft.In the present thesis, part-out-based spares provisioning (PBSP) program is proposed to utiliseretired aircraft units effectively as spare parts. The proposed approach is illustrated andverified through a case study performed on the “Saab-105” military aircraft fleet withinSwedish air force fleet. A PBSP programme is proposed, associated management activitiesare described, the key decision criteria are presented, and a functional framework for aneffective PBSP is suggested. The proposed PBSP program provides a foundation for furthermeasures and tasks to be performed within the retirement period, such as terminatingmaintenance contracts, discarding internal maintenance capabilities, reviewing stocks, scalingdown administrative processes (e.g. spares procurement and obsolescence monitoring), etc.An important part of the PBSP programme is the reliability analysis of multiple repairableunits, and this has been investigated, using parametric and non-parametric reliabilityapproaches. The aim is to identify a practical approach for estimation of the future sparedemand at fleet level. Furthermore, a set of computational models and search algorithm havebeen developed for the identification of applicable termination times, of both the parting-outprocess and the maintenance and repair actions performed on the units. This includestermination of the parting-out process (PO), the sending of parted-out units directly to storage(POS), and repair actions performed on the units received at the repair shops owing tocorrective (CM) and preventive (PM) maintenance, as well as the parted-out units that need tobe repaired (POM). The feasible termination alternatives are compared with regard to theirrespective costs and the most cost-effective solutions are identified.The results of the research study show that a PBSP programme can yield large reductions inmaintenance and spares procurement costs, while supporting operation of existing fleet athighest required availability. It also contributes positively to implement a green supply chainduring the retirement phase. The methodology and approaches introduced within the thesiscan be applied in other civil applications, such as energy, mining, process industry andtransportation sectors.

This thesis deals with optimization of inventory of spare parts and maintenance materials in NET4GAS, s.r.o. The aim of the thesis is to sort the items stored in the company and to propose specific supply methodology for the year 2013. The thesis is divided into two parts. The first, theoretical part includes theoretical knowledge of inventory management together with the methods used in the managing process, it also introduces specific inventory management of spare parts and maintenance materials. The second, practical part describes NET4GAS, s.r.o., its current system of inventory management of spare parts and maintenance materials, it identifies the local current problems in inventory management, it proposes selection of appropriate methods of inventory optimization and it demonstrates their application to real data. For the classification of stored items is selected ABC method. To draw up the supply plan is primarily used bootstrap method (also called bootstrapping), which makes estimates of future consumption of spare parts and maintenance materials. The final section summarizes all the recommendations for improving the current inventory management.

“Moto Spare Parts” es una idea de negocio, una empresa multimarca que comercializa kits de repuestos originales para motocicletas. Asimismo, esta propuesta va en sinergia con el estilo de vida que han adoptado varias personas en Lima Metropolitana. Es por ello que se canaliza la comercialización a través de un aplicativo móvil. En Perú, debido a las medidas de confinamiento (Covid-19), se incrementó el comercio electrónico de productos y como consecuencia el servicio de delivery está en todo su apogeo, sobre todo para aquellos que usan la motocicleta como herramienta de trabajo. Sin embargo, debido al incremento de este servicio, las motocicletas requieren un mantenimiento más frecuente, es por ello que los clientes buscan casas de repuestos o tiendas multimarca confiables. También, buscan reducir el tiempo que les toma adquirir el repuesto y el tiempo de entrega. En relación a ello, se desarrolló el aplicativo móvil que tiene como segmento de clientes mujeres y hombres de 18 a 39 años del NSE B y C de las zonas de 2, 3, y 10 de Lima Metropolitana, quienes son consumidores de repuestos para el mantenimiento de motocicletas y optan por comprar los repuestos a través de plataformas digitales. Para realizar el proyecto se necesitará una inversión de S/ 157,213.00, la cual está compuesta por el aporte de accionistas. Se ofrecerá una tasa de rentabilidad de 14.61% y se espera recuperar la inversión en 2 años. / "Moto Spare Parts" is a business idea, a multi-brand company that sells original spare parts kits for motorcycles. Additionally, this proposal is in cooperation with the lifestyle adopted by several people in Metropolitan Lima. That is why selling is through mobile applications. In Peru, due to confinement measures (Covid-19), electronic commerce of products increased and so the delivery service is on peak, especially for those who use the motorcycle as a work tool. However, due to the increase in this service, motorcycles require more frequent maintenance, which is why customers look for reliable spare parts houses or multi-brand stores. Also, they look to reduce the time it takes to buy the part and the delivery time. In relation to this, the mobile application was developed, having has as a segment of customers, women, and men between 18 and 39 years of the NSE B and C of the zones 2, 3 and 10 of Metropolitan Lima, who are consumers of spare parts for maintenance of motorcycles and choose to buy spare parts through digital platforms. To develop the project, we will need an investment of S/ 157,213.00 PEN, which is made up of the contribution of shareholders. A 14.61% rate of return will be offered, and the investment is expected to be recovered in the 2 year. / Trabajo de investigación