Programación de operaciones para el llenado de tolvas dosificadoras en una empresa de concentrados

En el presente artículo de investigación se desarrolla una propuesta de programación de operaciones que garantiza la toma eficiente de decisiones en el mediano y corto plazo de las industrias fabricantes de alimento concentrado. La metodología planteada parte de la generación de la explosión de materiales bajo el enfoque del MRP y posteriormente continúa con el desarrollo de un modelo de programación lineal entera mixta que coordina las operaciones de llenado de tolvas dosificadoras de manera que se cuente oportunamente con las materias primas requeridas en el proceso de dosificación y se minimicen los costos relevantes en el sistema. La propuesta se aplicó a un caso de estudio con datos reales y presentó mejores resultados que los obtenidos en la práctica por esta industri

Programação de operações em duas etapas para um flow shop multiperíodo não tradicional

This documents presents a detailed review of a two-stage approach to scheduling operations in a multi-period flow shop where various tasks have to be completed in the same time window. Some tasks are delivered immediately and must be scheduled as early as possible within the time window. Others are carried out in the latest stage in order to minimize their time of permanence in the system. It proposes a time decomposition strategy to address the multi-period issue, combining structured programming and linear programming in such a way that, for each period, two stages are run consisting of two mathematical models that schedule tasks based on their priority. The proposed approach was validated through the resolution of the problem of scheduling work for a feed manufacturing company where a schedule was prepared for each time period, meeting the requirements for immediate delivery products and those which can be delivered at a later point in time. The schedule minimizes the work-in-progress inventory of the first and the time of non-permanence in the system of the latter.En el presente documento se desarrolla una metodología de dos etapas para programar las operaciones en un flowshop multiperíodo, en éste se tienen trabajos que aunque que se deben terminar en la misma ventana de tiempo, unos son de entrega inmediata y deben programarse en el momento más temprano de la ventana, y otros en el momento más tardío, de tal modo que se minimice su tiempo de permanencia en el sistema. Se plantea una estrategia de descomposición temporal para el problema multiperíodo, en la que se combina la programación estructurada con la programación lineal, de tal modo que para cada periodo se corren dos fases compuestas de dos modelos matemáticos que programan los trabajos según su prioridad. La metodología planteada se valida en un problema de programación de trabajos en la industria de alimentos concentrados, obteniéndose como resultado un scheduling para cada periodo que satisface los requerimientos de los productos de entrega inmediata y los de entrega en el momento más tardío. Del tal modo que se minimiza para los primeros el inventario de producto en proceso y para los segundos el tiempo de no permanencia en el sistema.No presente documento, desenvolve-se uma metodologia de duas etapas para programar as operações em um flow shop multiperíodo, nele há trabalhos que embora devem terminar na mesma janela de tempo, uns são de entrega imediata e devem programar-se no momento mais cedo da janela e outros no momento mais tardio, de tal modo que se minimize seu tempo de permanência no sistema. Apresenta-se uma estratégia de descomposição temporal para o problema multiperíodo, na qual se combina a programação estruturada com a programação linear, de tal modo que para cada período correm duas fases compostas de dois modelos matemáticos que programam os trabalhos conforme sua prioridade. A metodologia apresentada valida-se em um problema de programação de trabalhos na indústria de alimentos concentrados, obtendo-se como resultado uma programação para cada período de tempo que satisfaça os requerimentos dos produtos de entrega imediata e os de entrega no momento mais tardio. Del tal modo que se minimiza para os primeiros o inventário de produto no processo e para os segundos o tempo de não permanência no sistema

Stochastic petri nets in the impact of the capacity in the service in mass-produced restaurants

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 characterizedin 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

Stochastic petri nets in the impact of the capacity in the service in mass-produced restaurants

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 characterizedin 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

El proceso de análisis jerárquico (AHP) y la toma de decisiones multicriterio. Ejemplo de aplicación.

Los problemas de toma de decisiones son procesos complejos en los cuales intervienen múltiples criterios, por lo cual es necesario utilizar herramientas que permitan discernir entre estos para obtener una solución que satisfaga en mejor grado la combinación de alternativas posibles. Una de estas herramientas, es el AHP (Proceso de Análisis Jerárquico). En este artículo se presenta el método, y un ejemplo de aplicación del mismo

El proceso de análisis jerárquico (AHP) y la toma de decisiones multicriterio. Ejemplo de aplicación.

Los problemas de toma de decisiones son procesos complejos en los cuales intervienen múltiples criterios, por lo cual es necesario utilizar herramientas que permitan discernir entre estos para obtener una solución que satisfaga en mejor grado la combinación de alternativas posibles. Una de estas herramientas, es el AHP (Proceso de Análisis Jerárquico). En este artículo se presenta el método, y un ejemplo de aplicación del mismo

Supply Chain Network Design of Perishable Food in Surplus Periods

Research on the design of the perishable food supply chain network has increased in recent years. However, little attention has been given to those seasonal foods that generate periods of oversupply and, particularly, to their impact on the sustainability of small producers in developing countries. This research proposes and develops a multi-objective mixed linear programming model for perishable fruits in a south American country at oversupply periods. It minimizes losses and transportation costs and maximizes the inclusion of farmers. It considers four echelons of the supply chain: farms, collection centers, distribution centers and the demand, which is represented by the agroindustry, wholesalers, shopkeepers, and hypermarkets. The Epsilon constraint method is used to solve the multi-objective model. A set of Pareto optimal solutions helped evaluate tradeoffs between the three objectives and find the location of collection and distribution centers. The proposed generic mathematical model is applicable to any food supply chain, as it allows for the improvement of the established performance measures and the distribution flows for the different echelons. The model considers the losses in perishable food from the impacts caused by changes in temperature (T0) and humidity level (RH) at different thermal floors of mountain ranges

Last mile logistics in mega-cities for perishable fruits

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 Reviewe

Programación de operaciones para el llenado de tolvas dosificadoras en una empresa de concentrados

En el presente artículo de investigación se desarrolla una propuesta de programación de operaciones que garantiza la toma eficiente de decisiones en el mediano y corto plazo de las industrias fabricantes de alimento concentrado. La metodología planteada parte de la generación de la explosión de materiales bajo el enfoque del MRP y posteriormente continúa con el desarrollo de un modelo de programación lineal entera mixta que coordina las operaciones de llenado de tolvas dosificadoras de manera que se cuente oportunamente con las materias primas requeridas en el proceso de dosificación y se minimicen los costos relevantes en el sistema. La propuesta se aplicó a un caso de estudio con datos reales y presentó mejores resultados que los obtenidos en la práctica por esta industri