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Purpose: The logistics network design (LND) lead to different supply, storage and distribution process and result in the flows, these logistics operations have an impact on the performance of the chain of fresh agricultural products. Specifically, in the perishable food supply chain (PFSC) with seasonality, a temporary imbalance between supply and demand is generated, which affects the balance in the flows and affects the losses, costs and response capacity. The location of stakeholders, production, transformation, commercialization and distribution facilities generate the configuration of the PFSC. Likewise, seasonality affects flows and decisions made by actors, which would generate the need to change the configuration of the PFSC. This research proposes a multi-objective, multi-product, multi-echelon for LND model in seasonal PFSC from a developing country with a topography of mountain ranges, where trucks don’t refrigerated and inadequate packaging used allow the food to be affected by the variations in altitude, changes in temperature (T0) and relative humidity (RH). The model was evaluated through a case study in fresh fruits. Design/methodology/approach: Tow mixed linear programming (MILP) multi-objective sub-models are established that determines the multiple configurations of the logistics network of the PFSC with seasonally and allows stakeholders to approach efficiency frontiers, which contribute to their permanence in the markets. The model was applied to the case of the perishable fruit supply chain, in a developing country, Colombia. The population information was taken from government surveys and studies, which allowed parameterizing the model. Findings: The application of model permitted to answer the next questions: How does improve the performance from seasonal PFSC through logistics network design? And, How the existence of smallholdings in food production and from retail merchants is preserved? It is necessary, on this context of the seasonal per, Peer Reviewed

En el contexto actual es importante que el ruteo de buses escolares (SBRP) además de la eficiencia aborde también las dimensiones social y ambiental, para garantizar soluciones sostenibles. La dimensión ambiental ha sido abordada ampliamente en el VRP, sin embargo, el SBRP no ha contado con la misma suerte, a pesar de que existen estudios sobre la relación entre los problemas ambientales en el trasporte escolar y salud de los niños, no obstante, no se encuentran trabajos que aborden la dimensión ambiental en el ruteo de buses escolares, en tal sentido este artículo aborda el SBRP con consideraciones ambientales. Se formula un modelo matemático que minimiza el consumo de combustible, que se calcula en función de la distancia recorrida, el peso de los vehículos y el de los estudiantes. El modelo es resuelto de manera óptima para instancias pequeñas, y para instancias de mayor tamaño se emplea un algoritmo basado en Búsqueda Tabú Granular. La solución inicial es generada por el algoritmo de ahorros. Se evalúa el rendimiento del algoritmo comparando los tiempos y valores de función objetivo con respecto al método exacto, la meta heurística generó soluciones 99,96% en promedio más rápido que el método exacto y generó soluciones con valor de función objetivo alejado en promedio 13,98% de las del método exacto. En este trabajo se hace una extensión al SBRP, adicionando la dimensión ambiental, aproximado el consumo de combustible en función de la distancia y el peso.

In competitive markets, flexibility is a key requirement to compete, group technology allows you to obtain this flexibility at a low cost, because it combines the advantages of mass production with the advantages of production by workshops Objective. Create a methodology that integrates the plans of: plant configuration, capacity and production, evaluating multiple criteria to select the grouping alternatives with better results. Materials and methods, five stages are articulated to achieve the objective: a. Creation of product families, b. Configuration of plant, capacity and production, c. Estimation of performance measures and d. Process of hierarchical analysis. Results: A consistent methodology is achieved regarding the sensitivity of the AHP evaluation of the performance measures, the individual variations in the criteria of the candidate configurations do not modify the decision found (configuration to be selected). Conclusion. It is possible to address the problem of cell formation considering an approach in which the problem is broken down into less complex sub-problems and thus include multiple grouping criteria at the time oriented to the environment where the methodology is applied, In competitive markets, flexibility is a key requirement to compete, group technology allows you to obtain this flexibility at a low cost, because it combines the advantages of mass production with the advantages of production by workshops Objective. Create a methodology that integrates the plans of: plant configuration, capacity and production, evaluating multiple criteria to select the grouping alternatives with better results. Materials and methods, five stages are articulated to achieve the objective: a. Creation of product families, b. Configuration of plant, capacity and production, c. Estimation of performance measures and d. Process of hierarchical analysis. Results: A consistent methodology is achieved regarding the sensitivity of the AHP evaluation of the performance measures, the individual variations in the criteria of the candidate configurations do not modify the decision found (configuration to be selected). Conclusion. It is possible to address the problem of cell formation considering an approach in which the problem is broken down into less complex sub-problems and thus include multiple grouping criteria at the time oriented to the environment where the methodology is applied.

in the current context it is important that the School Bus Routing Problem (SBRP) in addition to efficiency also addresses the social and environmental dimensions, to ensure sustainable solutions. The environmental dimension has been widely addressed in the VRP, however, the SBRP has not had the same development, although there are studies on the relationship between environmental problems in school transport and children's health, however, there are no jobs that address the environmental dimension in the SBRP, in this sense this article addresses the SBRP with environmental considerations. A mathematical model is formulated to minimize fuel consumption, which is calculated based on the distance traveled, the weight of the vehicles and the students. The model is optimally solved for small instances, and for larger instances an algorithm based on Granular Tabu Search is used. The initial solution is generated by the savings algorithm. The performance of the algorithm is evaluated by comparing the times and values of objective function with respect to the exact method, the times of solution with the metaheuristic were 99.96% on average faster than the exact method, however the objective values was far on average 13.98% of the exact method. In this work an extension to the SBRP is made, the environmental dimension is added, approximate the fuel consumption according to the distance and the weight., En el contexto actual es importante que el ruteo de buses escolares (SBRP) además de la eficiencia aborde también las dimensiones social y ambiental, para garantizar soluciones sostenibles. La dimensión ambiental ha sido abordada ampliamente en el VRP, sin embargo, el SBRP no ha contado con la misma suerte, a pesar de que existen estudios sobre la relación entre los problemas ambientales en el trasporte escolar y salud de los niños, no obstante, no se encuentran trabajos que aborden la dimensión ambiental en el ruteo de buses escolares, en tal sentido este artículo aborda el SBRP con consideraciones ambientales. Se formula un modelo matemático que minimiza el consumo de combustible, que se calcula en función de la distancia recorrida, el peso de los vehículos y el de los estudiantes. El modelo es resuelto de manera óptima para instancias pequeñas, y para instancias de mayor tamaño se emplea un algoritmo basado en Búsqueda Tabú Granular. La solución inicial es generada por el algoritmo de ahorros. Se evalúa el rendimiento del algoritmo comparando los tiempos y valores de función objetivo con respecto al método exacto, la meta heurística generó soluciones 99,96% en promedio más rápido que el método exacto y generó soluciones con valor de función objetivo alejado en promedio 13,98% de las del método exacto. En este trabajo se hace una extensión al SBRP, adicionando la dimensión ambiental, aproximado el consumo de combustible en función de la distancia y el peso.

Introduction: In a production Line it’s important that the stations’ cycle times are balanced and that they are low since this allows to reduce the work in process. However, doing this leads to an increase in the stations’ number, that is not favorable because it raises the costs associated with the stations, therefore it is necessary to define strategies that allow achieving a balance between these requirements. Objective: In this article we propose the formulation of a model for the line balancing, using the technique of multi-objective goal programming, applied to the pharmaceutical industry in order to minimize the stations’ number, minimize cycle time and inventory in process. Methodology: Goal programming is used to address a line balance model, which considers at the same time the assignment of multiple stations to one operation and the assignment of multiple operations to one station. Results: A significant decrease in cycle time and idle time at minimum costs is achieved, and a comparison between the deterministic and stochastic models is presented. Conclusions: Through this implementation of the LINGO model, the compliance of the proposed restrictions, the precedence of operations and the proper functioning of the model were validated through the optimal solutions obtained. The simulation is a tool that illustrates the complexity of the operations of the production system, which require, as in our case, more realistic modeling to understand the behavior of the process and evaluate different strategies., Introducción: En una línea de fabricación es muy importante que los tiempos de ciclo de las diferentes estaciones estén balanceados y que sean bajos, ya que esto permite disminuir los inventarios de producto en proceso, sin embargo, hacer esto conlleva a aumentar el número de estaciones, lo que no es favorable ya que eleva los costos fijos asociados a las estaciones, en tal sentido es necesario definir estrategias que permitan lograr un equilibrio entre estos requerimientos. Objetivo: En este artículo se propone la formulación de un modelo para el balanceo de línea, utilizando la técnica de programación multiobjetivo por metas, aplicada a la industria farmacéutica con el fin de minimizar el número de estaciones, minimizar el tiempo de ciclo y el inventario en proceso. Metodología: Se emplea la programación por metas para abordar un modelo de balance de línea, que considera al mismo tiempo la asignación de múltiples estaciones una operación y la asignación de múltiples operaciones a una estación. Resultados: Se logra una reducción significativa del tiempo ciclo y del tiempo ocioso a costos mínimos, además se presenta una comparación entre el modelo determinístico y estocástico. Conclusiones: A través de esta implementación del modelo en LINGO, se validó el cumplimiento de las restricciones planteadas, la precedencia de las operaciones y el buen funcionamiento del modelo mediante las soluciones óptimas obtenidas. La simulación, es una herramienta que permite ilustrar la complejidad de las operaciones del sistema de producción, las cuales requieren como en nuestro caso de una modelación más ajustada a la realidad para comprender el comportamiento del proceso y evaluar diferentes estrategias

In competitive markets, flexibility is a key requirement to compete, group technology allows you to obtain this flexibility at a low cost, because it combines the advantages of mass production with the advantages of production by workshops Objective. Create a methodology that integrates the plans of: plant configuration, capacity and production, evaluating multiple criteria to select the grouping alternatives with better results. Materials and methods, five stages are articulated to achieve the objective: a. Creation of product families, b. Configuration of plant, capacity and production, c. Estimation of performance measures and d. Process of hierarchical analysis. Results: A consistent methodology is achieved regarding the sensitivity of the AHP evaluation of the performance measures, the individual variations in the criteria of the candidate configurations do not modify the decision found (configuration to be selected). Conclusion. It is possible to address the problem of cell formation considering an approach in which the problem is broken down into less complex sub-problems and thus include multiple grouping criteria at the time oriented to the environment where the methodology is applied.

In Colombia, the small rice plantations must be associated with nearby ones to decrease the fixed costs of harvesting. These associations contract with third parties the mowing, threshing and cleaning combined machines of the grain. In the search for efficiency, the process of scheduling the dates in which each crop will be served by the combined machines must be managed in a centralized manner, taking into account the different machines efficiencies, the conditions of the land and the cost overruns for violating the windows time associated with the harvest time of the crops. In this sense, this article develops a solution to address the described problem, based on a whole linear programming model which minimizes the overall harvest costs and the costs of harvesting the crops in premature or anticipated moments. The model was validated in one of the associations, which showed results that minimize the total cost of machinery allocation by 7.04%., En Colombie, les petites rizières doivent s’associer aux plantations voisines pour diluer les coûts fixes de la récolte. Ces associations sous-traitent à des tiers les machines combinées chargées de la tonte, du battage et du nettoyage du grain. Dans la recherche de l’efficacité, le processus de planification des dates auxquelles chaque machine sera desservie par les machines combinées doit être géré de manière centralisée, en tenant compte des différences d’efficacité entre les machines, les conditions du terrain et les dépassements de coûts pour violation des fenêtres de temps associé au moment de la récolte des cultures. En ce sens, ce travail développe une proposition de gestión pour résoudre le problème décrit, basée sur un modèle de programmation linéaire, qui minimise les coûts de la récolte effectuée à temps et les coûts de la récolte prématuréee. Le modèle a été validé dans l’une des associations où des résultats ont été obtenus, ce qui a permis de réduire le coût total de l’attribution de machines en 7,04%., Na Colômbia, as pequenas plantações de arroz devem se associar com as próximas para diluir os custos fixos da colheita. Estas associações contratam com terceiros as máquinas combinadas que estão encarregadas de cortar, debulhar e limpar o grão. Na busca pela eficiência, o processo de agendamento das datas em que cada cultura será atendida pelas máquinas combinadas deve ser gerenciado de forma centralizada, considerando as diferentes eficiências da máquina, as condições do terreno e os custos excedentes por violar as janelas de tempo associado ao tempo de colheita das culturas. Neste sentido, este trabalho desenvolve uma proposta de gestão para abordar o problema descrito, baseado em um modelo de programação linear que minimiza os custos da colheita que é feita em tempo e os custos de colheita das culturas em momentos prematuros ou antecipados. O modelo foi validado em uma das associações, onde foram obtidos resultados que reduzem o custo total de alocação de maquinário em 7,04%., En Colombia las pequeñas plantaciones de arroz deben asociarse con otras cercanas para diluir los costos fijos de cosecha. Estas asociaciones contratan con terceros las máquinas combinadas que son las encargadas de hacer la siega, la trilla y la limpieza del grano. En la búsqueda de la eficiencia se debe gestionar de manera centralizada el proceso de programación de las fechas en que cada cultivo será atendido por las máquinas combinadas, considerando las diferentes eficiencias de las máquinas, las condiciones del terreno y los sobrecostos por violar las ventanas de tiempo asociadas al tiempo de cosecha de los cultivos. En tal sentido, el presente trabajo desarrolla una propuesta de gestión para abordar la problemática descrita, basada en un modelo de programación lineal entero, el cual minimiza los costos de la cosecha que se realiza a tiempo y los costos por cosechar los cultivos en momentos prematuros o anticipados. El modelo fue validado en una de las asociaciones, en donde se obtuvieron resultados que reducen en 7,04% el costo total de asignación de maquinaria.

Purpose: A common problem in mega cities is congestion, due to the size of the automotive park, this makes that the perishable foods decreasing their organoleptic characteristics or increases their losses, which requires considering the effect of time on routing problems. The state of the art demonstrates the need to formulate new routing models that include the specific characteristics of perishable foods in order to reduce their losses. Design/methodology/approach: A mathematical model was formulated based on two classical models: the three-index vehicle flow model proposed by (Golden, Assad, Levy & Gheysens, 1984) and the time window model proposed by (Cordeau, Desaulniers, Desrosiers, Solomon & Soumis, 1999). We proposed a novel VRP Model that permits reductions loss due to the perishable. Findings: The optimum cost is found with AMP® for twenty nodes, six vehicles and six fruits. For more nodes, a two-phase strategy is proposed, first a clustering based on a modified p-median model and then a VRP for each cluster. Research limitations/implications: The results showed the need to investigate multi-objective models, since the performance measures can be efficiency, quality and response capacity; the model can be applied in other supply chains of perishable foods. Social implications: According to FAO in Logistics practices in the last mile generate between 10-30% of the perishable food loss in developing countries’ mega-cities. Originality/value: A last-mile logistics strategy is proposed to manage delivery routes for fresh fruits in mega-cities, considering the effect of congestion through travel time in the perishability function. The new model it uses the flow variable to control the amount of each fruit arriving to each node and the time variable to define fruit waste or loss depending on the time and type of fruit., Peer Reviewed

in the present paper, a methodology based on stochastic petri nets is proposed to measure the impact caused by the capacity constraints of productive factors on the level of service in mass-produced restaurants. The system under study is identified and a discrete simulation model based on Stochastic Petri Nets is developed, which considers the most representative components and characteristics of the system and the interrelations between them. The test is performed in a restaurant that serves more than 4,500 lunches on day, where the impact of the production and service stages can be identified and the most critical and its effects were characterized, in the present paper, a methodology based on stochastic petri nets is proposed to measure the impact caused by the capacity constraints of productive factors on the level of service in mass-produced restaurants. The system under study is identified and a discrete simulation model based on Stochastic Petri Nets is developed, which considers the most representative components and characteristics of the system and the interrelations between them. The test is performed in a restaurant that serves more than 4,500 lunches on day, where the impact of the production and service stages can be identified and the most critical and its effects were characterized.

The present article proposes a methodology for warehouse inventory management of raw material for industries in the concentrated food sector. The methodology is divided in four phases. In the first phase, an ABC classification of the items was performed. In the second phase is determined the pattern, average, and variability of the demand for each item. Forecasts and calculation of the security inventories were made this way, based on the variability of demand and the desired level of service. Once the forecast systems for the demand of each item, the errors of the forecast, and the estimate of the last data has been defined, the inventory control policy was determined in the third phase. Finally, an optimization model is carried out that allows determine the storage place of the inventories of raw materials. This methodology aims to manage in an integrated manner the control of inventory and the location of items in warehouses of raw material in the concentrated food industry., Resumo Este artigo pretende discutir uma metodologia de gestão de estoque no armazém de matéria prima para indústrias no ramo de alimentos concentrados, definindo assim políticas de armazenamento e de controle de estoque. Na primeira fase, foi realizada uma classificação ABC de itens, que permitiu a gestão para estabelecer prioridades de administração e diferenciar sistemas de itens. Na segunda fase, foi determinado o padrão, a média, e a variabilidade de demanda para cada item no estoque. Assim, os cálculos e prognóstico de estoque de segurança, com base na variabilidade demanda e nível de serviço desejado, foram feitas. Uma vez, o sistema de previsão demanda para cada item sido definido, os erros de previsão, e os dados estimados, a política de controle de estoque foi definida na terceira fase. Finalmente, foi realizado um modelo de otimização que permitiu apoiar a implementação da gestão e armazenamento dos estoques de matérias--primas. Da mesma forma, esta metodologia permite a integração da política de controle de estoque e a localização deste no armazém, visto que uma boa disposição dos produtos afeta diretamente o controle de estoque, gerando resultado que as políticas de controle de estoque possam ter um impacto de forma direta na disposição de materiais., Resumen El presente artículo propone una metodología para la gestión de inventario en bodegas de materia prima para industrias del sector de alimentos concentrados. La metodología tiene cuatro fases. Como primera fase se realiza una clasificación ABC de los ítems. En la segunda fase se determina para la demanda de cada ítem el patrón, la variabilidad y se realizan los pronósticos; y tomando como base la variabilidad de la demanda y el nivel de servicio deseado, se define el inventario de seguridad para cada ítem. En la tercera fase establece la política de control de inventarios. Como fase final, se realiza un modelo de optimización que permite definir el lugar de almacenamiento de los inventarios de materias primas. Esta metodología tiene como objetivo gestionar de manera integrada el control de inventario y la ubicación de ítems en bodegas de materia prima en la industria de alimentos concentrados.

El presente artículo presenta una metodología basada en redes de Petri estocásticas para valorar el impacto que causan las restricciones de capacidad de los factores productivos sobre el nivel de servicio en un restaurante de producción masiva. Se identifica el sistema objeto de estudio y se desarrolla un modelo de simulación discreta en Redes de Petri Estocásticas, que tiene en cuenta los componentes y características más representativas del sistema y sus interrelaciones. La prueba es realizada en un restaurante universitario que sirve más de 4.500 almuerzo por día, donde se pudo identificar el impacto causado en las etapas de producción y servicio, y se caracterizaron los más críticos y sus efectos., in the present paper, a methodology based on stochastic petri nets is proposed to measure the impact caused by the capacity constraints of productive factors on the level of service in mass-produced restaurants. The system under study is identified and a discrete simulation model based on Stochastic Petri Nets is developed, which considers the most representative components and characteristics of the system and the interrelations between them. The test is performed in a restaurant that serves more than 4,500 lunches on day, where the impact of the production and service stages can be identified and the most critical and its effects were characterized.

In this work, a method to solve a motorcycle messenger routing problem with time windows is presented. This has two phases: in the first one, clusters of clients are formed, each group is assigned to a route and each route is served by a vehicle; in the second phase, through a mixed integer linear programming model the routing for each cluster is made while respecting hard time windows of some clients. To validate the method, the mail delivery section of a shared service center in Cali - Colombia is used as case study The results show that, when testing different clustering methods (phase l) these do not significantly influence the vehicle's duration on the road; On the other hand, regrouping the clients after routing (phase 2) can considerably improve the total duration of the route, although in some cases, increasing the distance traveled by the vehicle., RESUMO Neste trabalho se apresenta um método para a solução do problema de roteiro de mensageiros de motocicleta com janelas de tempo. Nele identificam-se duas fases: na primeira, conformam-se grupos de clientes, cada grupo é atribuído a uma rota e cada uma delas é servida por um veículo; na segunda, por meio de um modelo de programação linear todo misto, faz-se um roteiro para cada uma das agrupações respeitando as janelas de tempo estritas de alguns clientes. Para validar o método, usou-se como caso de estudo a área de mensageria de um centro de serviços compartilhados na cidade de Cali, na Colômbia. Os resultados mostram que ao testar diferentes métodos de agrupamento (fase l), não influem de maneira significativa no tempo total de permanência do veículo na rota; por outro lado, um reagrupamento dos clientes após do roteiro (fase 2), melhora consideravelmente a duração total do percurso, porém em alguns casos, aumenta a distância percorrida pelo veículo., RESUMEN Se presenta un método para la solución del problema de ruteo de mensajeros en motocicleta con ventanas de tiempo. En este se identifican dos fases: en la primera, se conforman grupos de clientes, cada grupo es asignado a una ruta y cada ruta es atendida por un vehículo; en la segunda, por medio de un modelo de programación lineal entera mixta, se hace un ruteo para cada una de las agrupaciones respetando las ventanas de tiempo estrictas de algunos clientes. Para validar el método, se utilizó como caso de estudio el área de mensajería de un centro de servicios compartidos de Cali, Colombia. Los resultados muestran que, al probar diferentes métodos de agrupación (fase 1), no se influye de forma significativa en el tiempo total de permanencia del vehículo en la ruta; en cambio, una reagrupación de los clientes después del ruteo (fase 2), mejora considerablemente la duración total de la ruta, aunque en algunos casos, aumenta la distancia recorrida por el vehículo.

Introduction: this study proposes a method to design and balance a cellular manufacturing system of a typical industrial company to obtain an optimal configuration in terms of the process, total cost, idle time and reliability criteria. Methods: the developed method has three phases. The first phase obtains candidate solutions using optimization models to minimize the cycle time and total cost. In the second phase, the performance measures for the remaining criteria of each candidate solution are found using discrete-event simulation. In the last phase, the optimal configuration is selected using the analytic network process (ANP). Results: the proposed method was validated with a practical case, where the optimal configuration had the best reliability with a zero-smoothness index, which minimized the wasted time and excess inventory. However, it was not the configuration with the lowest cost. Conclusions: This method has two contributing elements: multiple lean criteria and the approach, which combines different solution strategies to select the best configuration in an integral manner., Introducción: esta investigación propone una metodología para diseñar y balancear un sistema de manufactura celular de una empresa industrial típica con el propósito de obtener una configuración óptima bajo los criterios de, proceso, costo total, tiempo ocioso y confiabilidad. Métodos: la metodología desarrollada tiene tres fases. La primera fase consiste en obtener soluciones candidatas usando modelos de optimización para minimizar tiempo de ciclo y costo total. En la segunda fase se encuentran las medidas de desempeño de los demás criterios para cada solución candidata utilizando simulación de eventos discretos. En la última fase se escoge la configuración óptima utilizando el análisis de decisión multicriterio. Resultados: la metodología propuesta fue validada en un caso práctico donde la mejor configuración encontrada tiene la mayor confiabilidad, un índice de suavidad de cero que minimiza el desperdicio de tiempo y el exceso de inventario, aunque no fue la configuración con menor costo. Conclusiones: esta metodología tiene dos elementos de contribución: el primero, que involucra múltiples criterios lean, y el segundo, el enfoque que combina diferentes estrategias de solución para la selección de la mejor configuración de una manera integral.

Cutting stock problem abarca el tema de cortar grandes rollos de algún material (papel, textil, acero, madera, etc) en pequeñas tiras de diferentes anchos, que se utilizan como materia prima para la fabricación de un producto final. En este trabajo se presenta inicialmente una introducción de lo que significa en complejidad la solución de un problema de este tipo en una empresa. Luego se enuncian sus antecedentes mediante los trabajos más importantes encontrados en la literatura, destacando algunos trabajos Colombianos. Posteriormente, recordamos la clasificación propuesta por Dyckhoff en 1990 y se aportan sugerencias de otros aspectos a tener en cuenta cuando se aborda el Cutting stock problema. Finalmente se enmarcan los cuatro enfoques de solución más comunes dando ideas para investigaciones futuras.

Introduction. This research addresses the problem of internal materials supply operations in a pre-milling type concentrate food plant. The required amount of raw materials for production in the internal supply chain is determined by minimizing the total relevant operational cost, made up by the setup cost and the stock maintenance cost, which maximizes efficiency of the resources used in the process. This study takes into account such factors as capacity of the hoppers, the time-dependent setup sequence, routes of supply hoppers, filling rates and supply times, based on a model of mixed-integer linear programming. Objective: Provide a strategy that allows efficient use of resources in the production process, subjected to the demand of materials from the material requirements planning (MRP) of the company under study. Materials and methods. The short-term multi-period model defines the scheduling of elevators and conveyors for each time period, and the amount of raw materials that is sent to each hopper and bins. Results. This research determines the amount of initial stock required to operate, as well as the operations strategy that the company under study must follow, so that it meets the demand for raw materials, making efficient use of the resources used in the production process. Conclusion. In the analysis of results and presentation of scenarios, the most representative cost, the one related to stock maintenance, could be observed. Since this is a critical factor for companies belonging to this sector, we present an innovative proposal, both in practice and in the literature, to contribute to minimizing the total setup cost and the cost of maintenance of raw material stock in hoppers through a rational use of resources., Introdução. Esta investigação aborda o problema de programação interna de materiais numa planta de alimentos concentrados, tipo pré-moagem. A quantidade necessária de matérias primas para a produção na cadeia de alimentação interna se determina perante a minimização do custo total relevante da operação, composto pelo custo de preparação e o custo de manutenção do inventário, o qual maximiza a eficiência dos recursos empregados no processo. Para isso se consideram fatores tais como a capacidade das funis, as rotas e velocidades de enchimento e os tempos de subministro conteúdos num modelo de programação lineal, inteira, mista. Objetivo. Brindar uma estratégia que permita o uso eficiente dos recursos empregados no processo, sujeitos à demanda interna de materiais do plano de requerimento de materiais (MRP) da empresa objeto de estudo. Materiais e métodos. O modelo múlti-período a curto prazo define em cada período de tempo a programação dos elevadores ou transportadores, e a quantidade de matérias primas que se envia a cada funil. Resultados. A investigação determina a quantidade de inventário inicial requerido para a operação, ademais da estratégia de operações que a companhia objeto de estudo deve seguir com o fim de satisfazer a demanda de matérias primas, fazendo uma utilização eficiente dos recursos empregados no processo produtivo. Conclusao. Na análise dos resultados e na apresentação dos cenários, o custo mais representativo é o relacionado com a manutenção do inventário; este é um fator crítico nas empresas pertencentes a este setor. Por isso, se apresenta uma proposta inovadora para este tipo de processos produtivos, com o fim de contribuir a minimizar o custo de total de preparação e o custo de manutenção das existências de matéria prima em funis perante um uso racional dos recursos., Introducción. Esta investigación aborda el problema de programación interna de materiales en una planta de alimentos concentrados, tipo pre-molienda. La cantidad necesaria de materias primas para la producción en la cadena de alimentación interna se determina mediante la minimización del costo total relevante de la operación, compuesto por el costo de alistamiento y el costo de mantenimiento del inventario, lo cual maximiza la eficiencia de los recursos empleados en el proceso. Para ello se consideran factores tales como la capacidad de las tolvas, las rutas y velocidades de llenado y los tiempos de suministro contenidos en un modelo de programación lineal, entera, mixta. Objetivo. Brindar una estrategia que permita el uso eficiente de los recursos empleados en el proceso, sujetos a la demanda interna de materiales del plan de requerimiento de materiales (MRP) de la empresa objeto de estudio. Materiales y métodos. El modelo multi-período a corto plazo define en cada período de tiempo la programación de los elevadores o transportadores, y la cantidad de materias primas que se envía a cada tolva. Resultados. La investigación determina la cantidad de inventario inicial requerido para la operación, además de la estrategia de operaciones que la compañía objeto de estudio debe seguir con el fin de satisfacer la demanda de materias primas, haciendo una utilización eficiente de los recursos empleados en el proceso productivo. Conclusión. En el análisis de los resultados y en la presentación de los escenarios, el costo más representativo es el relacionado con el mantenimiento del inventario; este es un factor crítico en las empresas pertenecientes a este sector. Por ello, se presenta una propuesta innovadora para este tipo de procesos productivos, con el fin de contribuir a minimizar el costo de total de alistamiento y el costo de mantenimiento de las existencias de materia prima en tolvas mediante un uso racional de los recursos.