We report on an industrial project in which we developed an inventory model to provide decision support for the design and deployment of the field service support system for a remanufacturable product. The product was a dialysis unit for home use. Each unit that was installed in a home would eventually be removed due to failure, or the need for preventative maintenance, or the termination of the service. Upon removal, each unit was shipped to a central depot for re-manufacturing so that it could be returned to service. We develop a model to determine the inventory requirements at each regional depot, and then describe how to use the model to determine the inventory requirements in the two-echelon system consisting of the central facility and the regional depots. / Singapore-MIT Alliance (SMA)

The companies ought to care about OEE because it is a measure that shows the effect of the performance and quality related losses on the system or equipment. In order to improve OEE, they focus on defining the losses under each OEE elements and try to eliminate these losses.This study aims to enhance raw material inventory management in order to eliminateinventory management related losses and improve OEE.  Lack of raw material and improperstorage of raw material are main problems related to inventory management. A model isdeveloped and tested in order to prevent these problems and eliminate these losses.Performance rate can be improved by preventing idle time due to lack of raw material, andquality rate can be improved by standardization and improving raw material storageprocedure. In the result of model testing, it is shown that raw material inventory managementhas an effect on OEE and OEE can be improved by enhancing raw material inventorymanagement.

Today, like years ago, Cuba is involved in a continuous struggle to improve the economy in its numerous sectors withspecific emphasis in tourism industry, which has globally evolved as one of the most increasing phenomena. Cuba,not being exerted from that situation, has placed it as the engine of the economy based on a previous redirection of itseconomic strategy. For this reason, it is necessary to search new managerial alternatives and theories contributing to thisdevelopment. In particular, finance management catches a great attention as a function of enterprise administration, asit is in charge of managing the productive resources in such a way that the organization meets the expected economicand financial results: more efficiency, less risk involved and higher profitability. This important function affects considerablydecision making process in terms of: maintaining appropriate cash flow levels, types of terms of credit to offerto clients or cost-effective inventory levels. All these arguments have led to the main purpose of this investigation andthat is to propose a procedure for inventory planning in hotelier organizations. / Hoy, como hace años, Cuba está inmersa en una continua lucha por perfeccionar cada una de las ramas de la economíay cobra gran importancia el sector del turismo que, desde los años cincuenta, se ha erigido a escala mundial como unode los sectores de mayor crecimiento y que, desde el momento que se reconceptualiza la estrategia económica del país,es catalogado como «locomotora de la economía cubana». Por esta razón, es imprescindible el desarrollo investigativoprofesional que, de manera creciente, aporte alternativas y conocimientos que contribuyan al desarrollo continuo deeste perfeccionamiento. Así, las finanzas cobran especial importancia como función de la dirección, encargada de administrarlos recursos productivos para lograr los objetivos empresariales, traducidos en mejores niveles de crecimiento,riesgo y rendimiento. Entonces, la gestión financiera operativa —responsable de la conservación del adecuado efectivodisponible, de los términos de crédito a ofrecer a los clientes y de los inventarios que reduzcan los costos asociados conestos— juega un papel importante en la toma de decisiones. Al tener como argumento lo anterior, el objetivo generalde la presente investigación se dirige a proponer un procedimiento para el proceso de planeación de inventarios en elsector hotelero, ilustrado a partir de su aplicación en una instalación hotelera del polo turístico de Varadero.

This research introduces a general approach for integrating a probabilistic model of the changes in the committed orders with an analytical model of production and inventory planning under multi-period Quantity Flexibility contracts. We study a decentralized structure where a capacitated manufacturer, capable of subcontracting, serves multiple contract buyers who actually perform forecasts on a rolling horizon basis. We model the evolution of buyers&#039 / commitments as a multiplicative forecast evolution process accommodating contract revision limits. A finite Markovian approximation to this sophisticated evolution model is introduced for facilitating the associated complex probability modeling. We implement computational dynamic programming and introduce an effective approach for reducing state-space dimensionality building upon our forecast evolution structure. Computational investigation demonstrates how the manufacturer benefits from the existence of order commitments and subcontracting option by analyzing the interplay of decisions.

In this thesis, capacity-constrained aspects of multi-level, multi-stage productionplanning are investigated. The aim has been to extend Material Requirements Planning Theory (MRP Theory) to cover more general problems dealing with capacity constraints, in particular when non-zero lead times are present and the processes take place in continuous time. MRP Theory deals with multi-level production systems with multiple items taking place either within a discrete or continuous time framework. External demand is considered either deterministic or stochastic. Lead times are assumed to be given constants, and the Net Present Value Principle has been applied as the objective function. The Bill-of-Materials, capturing component as well as capacity requirements, in volume as well as in advanced timing due to lead times, has been described using a generalised input matrix involving Laplace transforms or z transforms. In order to be able to apply Dynamic Programming as a solution method, the system state has been defined and designed in terms of a matrix, in which historical values of cumulative production and cumulative demand are given state variables. A high power computer has been used to calculate solutions to numerical examples. Moreover, this thesis examines the fundamental equations of MRP Theory in order to analyse the possibility to obtain closed-form expressions for the time development of the system, when standard ordering rules of MRP are applied. In addition, capacity-constrained production planning problems and procedures in a paper mill have been surveyed and are presented in the form of a case study.

Submitted by Livia Mello (liviacmello@yahoo.com.br) on 2016-10-11T20:12:25Z No. of bitstreams: 1 DissTSK.pdf: 3524235 bytes, checksum: 7f004fb5c47d3a888f9b19f884f38946 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-21T12:58:59Z (GMT) No. of bitstreams: 1 DissTSK.pdf: 3524235 bytes, checksum: 7f004fb5c47d3a888f9b19f884f38946 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-21T12:59:07Z (GMT) No. of bitstreams: 1 DissTSK.pdf: 3524235 bytes, checksum: 7f004fb5c47d3a888f9b19f884f38946 (MD5) / Made available in DSpace on 2016-10-21T12:59:15Z (GMT). No. of bitstreams: 1 DissTSK.pdf: 3524235 bytes, checksum: 7f004fb5c47d3a888f9b19f884f38946 (MD5) Previous issue date: 2016-05-19 / Não recebi financiamento / This dissertation studies the application of a periodic review inventory model based on the multiperiod newsboy problem, as an effective alternative to reach a well balanced inventory planning policy of subcontractors primary parts area of the aerospace industry. In Brazil, the aerospace industry is responsible for a large amount of the country exports and this industry competes with other globally aerospace supply chains in a scenario increasingly turbulent and demanding for fast deliveries, with high quality levels and low cost. The purpose of this work is to study and propose this alternative for optimizing the inventory planning by means of a quantitative approach, applied in a primary parts sector of the aerospace industry, it will focus in a specific group of items with high annual demand value. The main objective of this approach is to balance the high inventory costs with a high service level demanded in this industry, and efficiently respond the stakeholders expectations, with superior performance of the usual models adopted by this industry, and give a better support to the decision makers in a tactical-operational level. The result obtained show the potential of the method to improve the performance of these inventory management and planning systems. / Este trabalho estuda a aplicação de um modelo analítico de revisão periódica de estoques, baseado no problema do jornaleiro multiperíodo (Multiperiod Newsboy Problem), como uma alternativa efetiva para determinação da política de planejamento de estoques do setor de peças primárias subcontratadas da indústria aeroespacial. No Brasil, a indústria aeroespacial é responsável por grande parte das exportações do país e compete globalmente com outras cadeias aeroespaciais num cenário cada vez mais turbulento e exigente por entregas rápidas, com altos níveis de qualidade e baixos custos. O objetivo deste trabalho é estudar e propor essa alternativa para otimizar o planejamento de estoques por meio de uma abordagem quantitativa, aplicada no setor de peças primárias da indústria aeroespacial, para um grupo de peças com características especificas, principalmente as de alto valor para demanda anual. O intuito desta abordagem é equilibrar os altos custos de estoque com os altos níveis de serviço exigidos por esta indústria, e responder de forma eficiente às expectativas dos stakeholders, com desempenho superior aos modelos atualmente utilizados no setor e auxiliar de forma mais precisa e sistematizada a tomada de decisão no nível tático-operacional. Os resultados obtidos mostram o potencial do método para melhorar o desempenho desses sistemas de gestão e planejamento de estoques.

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-06-19T13:13:53Z No. of bitstreams: 1 rodrigobarbosadesantis.pdf: 2597054 bytes, checksum: b19542ca0e9312572d8ffa5896d735db (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-06-27T11:12:01Z (GMT) No. of bitstreams: 1 rodrigobarbosadesantis.pdf: 2597054 bytes, checksum: b19542ca0e9312572d8ffa5896d735db (MD5) / Made available in DSpace on 2018-06-27T11:12:01Z (GMT). No. of bitstreams: 1 rodrigobarbosadesantis.pdf: 2597054 bytes, checksum: b19542ca0e9312572d8ffa5896d735db (MD5) Previous issue date: 2018-03-26 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Falta de materiais é um problema comum na cadeia de suprimentos, impactando o nível de serviço e eficiência de um sistema de inventário. A identificação de materiais com grande riscos de falta antes da ocorrência do evento pode apresentar uma enorme oportunidade de melhoria no desempenho geral de uma empresa. No entanto, a complexidade deste tipo de problema é alta, devido ao desbalanceamento das classes de itens faltantes e não faltantes no inventário, que podem chegar a razões de 1 para 100. No presente trabalho, algoritmos de classificação são investigados para proposição de um modelo preditivo para preencher esta lacuna na literatura. Algumas métricas específicas como a área abaixo das curvas de Característica Operacionais do Receptor e de Precisão-Abrangência, bem como técnicas de amostragem e comitês de aprendizado são aplicados nesta tarefa. O modelo proposto foi testado em dois estudos de caso reais, nos quais verificou-se que adoção da ferramenta pode contribuir com o aumento do nível de serviço em uma cadeia de suprimentos. / Material backorder (or stockout) is a common supply chain problem, impacting the inventory system service level and effectiveness. Identifying materials with the highest chances of shortage prior its occurrence can present a high opportunity to improve the overall company’s performance. However, the complexity of this sort of problem is high, due to class imbalance between missing items and not missing ones in inventory, which can achieve proportions of 1 to 100. In this work, machine learning classifiers are investigated in order to fulfill this gap in literature. Specific metrics such as area under the Receiver Operator Characteristic and precision-recall curves, sampling techniques and ensemble learning are employed to this particular task. The proposed model was tested in two real case-studies, in which it was verified that the use of the tool may contribute with the improvemnet of the service level in the supply chain.

No description available.

Este artículo tiene como objetivo solucionar el problema de ineficiencia, representado por el bajo nivel de servicio en el sistema de distribución de la planta de combustible, ya que se han presentado retrasos desde el inicio del proceso hasta el final de este. Por este motivo, se analizó todo el flujo del sistema para determinar en qué parte del proceso estaba la causa principal, lo que ayudaría a reducir considerablemente el problema. Se propuso aplicar un sistema de citas para estandarizar los tiempos de servicio, así como la implementación de un algoritmo y el uso de mecanismos eficientes para derivar la mejor solución robusta que responda a todas las incertidumbres con tiempos de ejecución reducidos. / This article aims to solve the inefficiency problem, represented by the low service level, in the fuel plant distribution system, since there have been delays from the beginning of the process to the end of this. For this reason, the entire flow of the system was analyzed in order to determine where in the process the main cause was, which would help reduce this problem considerably. It was proposed to apply an appointment system to standardize service times as well as the implementation of an algorithm and the use of efficient mechanisms to derive the best robust solution that responds to all uncertainties with reduced execution times. / Trabajo de investigación

En el presente trabajo de suficiencia profesional se examina el problema de desatenciones que ocurren durante el servicio de mantenimiento de vehículos en una empresa del sector automotriz. Para el desarrollo del estudio, se analizó una empresa del sector en la cual las desatenciones se encuentran entre el 40% y 50% del total de servicios realizados en el mes. Este problema representa una pérdida económica del 25% respecto a los ingresos mensuales, el cual se origina por la escasez de repuestos debido a la ineficiente planificación de inventarios. Por ello, para mitigar las roturas de stock, se desarrolló una propuesta para la planificación y gestión de las existencias por tipo de mantenimiento. Por un lado, se elaboró una propuesta para el proceso de planificación de repuestos de mantenimiento preventivo basado en el sistema E-Kanban. Por otro lado, se elaboró una propuesta para el proceso de planificación de repuestos de mantenimiento correctivo basado en un sistema ABC para la clasificación de los repuestos y un sistema de inventario EOQ (Lote de Compra Económica) para definir las cantidades y momentos de reposición. Este trabajo tiene como objetivo disponer de autopartes mecánicas en el momento solicitado lo cual ayudara a reducir las pérdidas económicas en un 84% el número de desatenciones en un 76%. Finalmente, se tiene proyectado recuperar la inversión en un periodo de un año y medio. / The present professional sufficiency work examines the problem of negligence during the vehicle maintenance service in an automotive company. For the development of the study, a company from the sector, whose negligence are between 40% and 50% of the total of services performed in the month, was analyzed. This issue, which represents an economic loss of 25% regarding its monthly income, is caused by the shortage of spare parts due to inefficient inventory planning. Therefore, to mitigate the stock-outs, a proposal was developed for planning and managing stocks by type of maintenance. On the one hand, a proposal was elaborated for the planning process of preventive maintenance spare parts based on the E-Kanban system. On the other hand, a proposal was prepared for the planning process of corrective maintenance spare parts based on an ABC system for the classification of spare parts and an EOQ (Economic Order Quantity) inventory system to define the quantities and replacement times. The objective of this work is to dispose of available mechanical auto parts at the requested time, which will help to reduce economic losses by 84% and the amount of negligence by 76%. Finally, it is projected to recover the investment in a period of a year and a half. / Trabajo de Suficiencia Profesional