Elias Olivares-Benitez

• PhD
• Professor at Universidad Panamericana Sede Guadalajara

The multi-mode resource-constrained project scheduling problem is an NP-hard optimization problem with practical applications in construction, software development, manufacturing, and other industrial and business situations. It involves a set of activities that need to be sequenced while considering precedence and resource constraints as well as d...

Background: Distribution systems often face the dual challenge of delivering products to customers and retrieving damaged items for repair, especially when the service center is separate from the depot. An optimized solution to this logistics problem produces benefits in terms of costs, greenhouse gas emissions, and disposal reduction. Methods: Thi...

Electric vehicles (EVs) offer significant potential for advancing sustainable environmental goals. However, their widespread adoption has been concentrated in urban areas, raising challenges for interurban travel. In many countries, charging station networks are primarily located within cities, highlighting a key opportunity for expansion to suppor...

This study investigates a location-routing problem with self-supply, open routes, and a fixed fleet, focusing on the trade-off between total traveling costs and vehicle contracting costs. A bi-objective approach is developed, comparing the impact of minimizing traveling costs versus vehicle contracting costs, which is the cost associated with vehic...

El principal objetivo de la investigación fue analizar elementos de la innovación no tecnológica, priorizando las variables de los beneficios y los sacrificios entre las empresas dedicadas al mármol y los clientes finales, con el propósito de determinar su grado de satisfacción y lealtad, para ello se realizó una investigación cuantitativa, no expe...

This research aims to develop a mathematical model and a solution approach for jointly optimizing a global inventory service level and order sizes for a single-commodity supply chain network with multiple warehouses or distribution centers. The latter face stochastic demands, such as most real-world supply chains do nowadays, yielding significant m...

A sustainable closed-loop supply chain network requires conjunctive implementation of reverse logistics in the supply chain, with decisions that consider economic, environmental, and social factors. In real life, the problem needs to be addressed by prioritizing targets or interacting between them to give a range of solutions to the decision maker....

Determination of the optimal operational policy for an automotive supply chain is explored under a centralized management approach using dynamic programming. A deterministic optimal control model is proposed to meet multi-product demand over a period while minimizing a cost performance index for a five-echelon network. The production-inventory leve...

Call for Abstracts

In this Special Issue, we are interested in the modeling and optimization to sustainable operations management in a broad sense. The aim of this Special Issue is to bring together high-quality contributions in multiple application fields tackling real-world optimization problems where mathematical programming-based methods are used. A particular in...

Blockchain is an emerging technology with the potential to radically transform logistics in the highly complex environment of the agri-food supply chain. The key challenges of the agri-food sector include overcoming the limitations (time, cost and quality) to developing global and efficient transparency and traceability of food, eliminating expensi...

This research introduces a stochastic version of the multi-mode resource-constrained project scheduling problem (MRCPSP) and its mathematical model. In addition, an efficient multi-start iterated local search (MS-ILS) algorithm, capable of solving the deterministic MRCPSP, is adapted to deal with the proposed stochastic version of the problem. For...

Currently, the Mexican avocado supply chain has some social limitations that make the traceability process a difficult task and severely limits the regions that can add their harvest to the international market. We hypothesize that modernizing the traceability process and improving the trust of the final user could help in opening the market to oth...

Purpose Small- and medium-sized enterprises (SMEs) mainly rely on their structure and internal networks to achieve their goals and remain competitive. However, their limited internal capabilities and complex environments can hinder their stability. Thus, this study evaluated the relationships among specific factors toward fostering organizational r...

Supply-chain network design is a complex task because there are many decisions involved, and presently, global networks involve many actors and variables, for example, in the automotive, pharmaceutical, and electronics industries. This research addresses a supply-chain network design problem with four levels: suppliers, factories, warehouses, and c...

In this paper a multi-start iterated local search (MS-ILS) algorithm is presented as a new and effective approach to solve the multi-mode resource-constrained project scheduling problem (MRCPSP). The MRCPSP is a well-known project scheduling NP-Hard optimization problem, in which there is a trade-off between the duration of each project activity an...

The supply chains around the agri-food sector are, in economic terms, one of the most relevant activities at an international level, employing millions of people, mainly in developing countries. The complexity of this supply chain includes key aspects related to the identification of food, from origin to final consumption. This article conceptually...

This article addresses the supplier selection and order quantity allocation problem. It introduces a model to minimize the total cost per time unit considering inventory and transportation costs. In selecting suppliers, two feasibility constraints are considered: capacity and perfect rate. The acceptable perfect rate of raw materials is ensured wit...

Growing concern about environmental deterioration, manifested in new laws to protect the environment and business competition, has stimulated the idea of Closed Loop Supply Chains (CLSC). This paper develops strategic decision-making models for two different CLSCs with multiple products over multiple periods. One of the networks has six levels, whi...

This paper addresses the so-called supplier-selection and order-quantity allocation problem. Because of the complexity of this of problem (e.g., non-linear, discontinuous cost function), a new heuristic method is proposed and tested. This heuristic method explores the search space in a short period of time to find cheaper solutions. In order to tes...

Sales territory design is an important research field because salesforce allocation within territories impacts sales organization effectiveness and customer service. This work presents a novel multi-objective model for re-designing sales territories with three main objectives: sales balancing, workload balancing, and geographic balancing. To measur...

Small and medium-sized tourism companies (SMEs) strongly depend on their collaborators to achieve competitiveness and sustainability. In this sense, these organizations need to identify those factors that help them to use their resources and efforts to achieve the aforementioned goals. This article proposes a model oriented to organizational sustai...

Supplier selection and order quantity allocation have a strong influence on a company’s profitability and the total cost of finished products. From an optimization perspective, the processes of selecting the right suppliers and allocating orders are modeled through a cost function that considers different elements, such as the price of raw material...

This paper introduces the multi-depot open location routing problem (MD-OLRP) with a heterogeneous fixed fleet. The problem is inspired by the collection problem of a company which collects raw materials from different suppliers coordinating several carriers. Each carrier has a heterogeneous fixed fleet. Moreover, there is a fixed cost for contract...

La creciente demanda de alimentos, la preservación de la calidad de los alimentos y la inocuidad de los alimentos son algunos de los desafíos que enfrenta la cadena de suministro agroalimentario en la actualidad. Este artículo muestra una revisión de algunas de las contribuciones realizadas por varios autores, basadas en procesos y actividades logí...

This paper studies the Cumulative Capacitated Vehicle Routing Problem, including Priority Indexes, a variant of the classical Capacitated Vehicle Routing Problem, which serves the customers according to a certain level of preference. This problem can be effectively implemented in commercial and public environments where customer service is essentia...

Location of small and large stores requires a market study to determine the demand for a product in a particular region, as well as the selection of the target population. However, it is common to forget analyzing the impact of the competition regarding the suitability of locating facilities. The objective of this work is to propose a model that ca...

The objective of this paper is to estimate the operational efficiency of Mexican water utilities and identify the context variables that impact their efficiency. In particular, a bootstrap data envelopment analysis (DEA) and a bootstrap truncated regression analysis are combined in a two-stage research method. In the first stage, an input-oriented...

In supply chain management, fast and accurate decisions in supplier selection and order quantity allocation have a strong influence on the company's profitability and the total cost of finished products. In this paper, a novel and non-linear model is proposed for solving the supplier selection and order quantity allocation problem. The model is int...

Featured Application The application of the value stream mapping (VSM) tool in the automotive industry was useful as a support to modify the logistics flow and consequently reduce the delivery time of the spare parts. Abstract In today’s automotive industry, Lean production systems are used successfully to reduce delivery times. The current case s...

This paper suggests a hybrid model to solve a distribution problem incorporating the impact of uncertainty in the solution. The model combines the deterministic approach and the simulation including stochastic variables such as harvest yield, loss risk and penalties/benefits to design a distribution network with the minimal cost. Through a case stu...

This chapter presents a case study to organize the sales territories for a company with 11 sales managers to be assigned to 111 sales coverage units in Mexico. The assignment problem is modeled as a mathematical program with two objective functions. One objective minimizes the maximum distance traveled by the manager, and the other objective minimi...

A MILP and genetic algorithm optimization model for the sequencing of jobs in a medium-sized factory, dedicated to the manufacturing of home furniture, where different categories and types of articles are produced and whose routes and manufacturing processing times vary widely, are proposed. Different scenarios are considered for the objective func...

Industrial systems, such as logistics and supply chain networks, are complex systems because they comprise a big number of interconnected actors and significant nonlinear and stochastic features. This paper analyzes a distribution network design problem for a four-echelon supply chain. The problem is represented as an inventory-location model with...

This chapter addresses a production planning problem for a company that mass-replicates compact discs. In the current situation, the staff of the company creates a production plan for the long term, with low flexibility to make a new plan when new orders arrive. The combination of attributes of the orders and the available machines for the processe...

Malted barley is the main raw material for brewing. In the last decade, Mexico has consolidated its position as the main beer brewer in the world. Freight and the operations related to the distribution of the harvest have an effect on the production costs and the amount of sawed, harvested and sold grain. This research study aimed at obtaining a mi...

Malted barley is the main raw material for brewing. In the last decade, Mexico has consolidated its position as the main beer brewer in the world. Freight and the operations related to the distribution of the harvest have an effect on the production costs and the amount of sawed, harvested and sold grain. This research study aimed at obtaining a mi...

This paper develops a location-allocation model to optimize a four-echelon supply chain network, addressing manufacturing and distribution centers location, supplier selection and flow allocation for raw materials from suppliers to manufacturers, and finished products for end customers, while searching for system profit maximization. A fractional-f...

This paper presents a biobjective problem for a solid waste collection system in a set of islands in southern Chile. The first objective minimizes transportation cost and the second one reduces the environmental impact caused by the accumulation of solid waste at the collection points. To solve this problem, biobjective mixed integer linear program...

El conservar la calidad a lo largo de la cadena de suministro agroalimentaria es un aspecto fundamental que identifica, hace única y diferente de cualquier otro tipo de cadena, de esta forma los modelos para la optimización y el diseño de redes logísticas se han enfocado recientemente en la evaluación e integración de funciones para el decaimiento...

La alta incertidumbre en la demanda y el suministro presentes en la cadena de suministro agroalimentaria ubican a la logística como elemento fundamental para mejorar el desempeño de esta cadena, en este sentido los modelos de optimización enfocados en las operaciones logísticas de transporte buscan reducir los costos asociados con el traslado de pr...

El siguiente estudio presenta una heurística basada en un algoritmo de dos fases para resolver un Periodic Vehicle Routing Problem (PVRP) por medio de una programación en código en C++. Las variables de decisión son los itinerarios por día que se deben elegir para cada cliente. El objetivo es minimizar los costos totales de las rutas por semana par...

El diseño de la logística busca dar soporte a las operaciones de transporte, distribución, almacenamiento, abastecimiento, identificación, control y seguimiento con el fin de incrementar el nivel de servicio al cliente generando mayores ingresos para la organización. En este sentido y en la particularidad de la cadena de suministro agroalimentaria...

En este trabajo se estudian los atributos del problema dinámico del control operacional de AGVs. Se discuten las implicaciones del uso de la información on-line como el principal elemento del carácter dinámico de los problemas. Seutiliza la taxonomía de Psaraftis para identificar los atributos (evolución, calidad, disponibiliad, y procesamiento) de...

Introducción: En este texto se presentan resultados estadísticos de la relación entre directivos con características de talento verde y la implementación de prácticas de cadena de suministro verde. Debido a que existen investigaciones sobre la importancia de la visión de la alta dirección para la adopción de prácticas verdes; y sin embargo ninguna...

This study presents a metaheuristic based on a multiobjective evolutionary algorithm to solve a biobjective mixed-integer nonlinear programming model for supply chain design with location-inventory decisions and supplier selection. The supply chain has four echelons with suppliers, plants, distribution centers, and retailers. The decision variables...

RESUMEN Un problema recurrente en cada inicio de periodo escolar en las Instituciones Educativas (IEs) es la calendarización de horarios de los profesores para un conjunto de grupos y cursos. En este trabajo se pretende optimizar la asignación de cursos a grupos en un conjunto de periodos de tiempo con determinados requerimientos. Se aborda este pr...

The authors present in this work a proposal that allows establishing the relationships between the facilities location problem and the client allocation within a dense demand environment in territorial design. This proposal can be seen as a basic methodology to give support to the decision making. The use of this application lets one know the produ...

Modular production and component commonality are two widely used strategies in the manufacturing industry to meet customers growing needs for customized products. Using these strategies, companies can enhance their performance to achieve optimal safety stock levels. Despite the importance of safety stocks in business competition, little attention h...

Introducción: En este texto se presentan resultados estadísticos de la relación entre directivos con características de talento verde y la implementación de prácticas de cadena de suministro verde. Debido a que existen investigaciones sobre la importancia de la visión de la alta dirección para la adopción de prácticas verdes; y sin embargo ninguna...

The order picking process is, perhaps one of the most costly operation within any warehouse, compared to the other main activities shipping, storage and receiving stages. Therefore, this work proposes a methodology that combines an optimization algorithm with a simulation model to perform the picking process. This resolution approach has different...

Despite the importance and potential for companies to minimize costs by reducing the safety stock levels using the modular product system, this has not been extensively studied; its study has been limited by the inherent complexity of the production system. The modular product system arises to try meeting the increasing demand of customized product...

This paper shows how researchers have focused their optimization studies in AGVs design and control optimization. This article discusses comprehensive approaches identified in other research papers. The four features examined were: focus problem, solution methodology, manufacturing environment, and metrics. The five dif- ferent optimization envir...

This paper presents a methodology for solving the Periodic Vehicle Routing Problem (PVRP). Customer locations each with a certain daily demand are known, as well as the capacity of vehicles. In this work, the problem is solved by means of a two-phase heuristic. The first phase is the itinerary assignment to visit each customer, and in the second ph...

The value of agricultural production in the State of Puebla ranks sixth nationally. However, the benefits for vegetable growers in the region have not been expected largely due to the absence of middlemen and analyses related to the value chain, logistics and supply chain. This study collected information from various actors in the value chain of p...

Introduction: In Mexico theft has become one of the most significant risks to the efficiency and competitiveness of supply chains. This proposal aims to identify the variables that influence the risk of theft in trucking transportation as a preliminary step of a methodology to quantitatively evaluate the influence of the identified variables and me...

The zones design occurs when small areas or basic geographic units (BGU) must be grouped into acceptable zones under the requirements imposed by the case study. These requirements can be the generation of intra-connected and/or compact zones or with the same amount of habitants, cli ents, communication means, public services, etc. In this second po...

We review the problem for the design of supply chains called Capacitated Fixed Cost Facility Location Problem with Transportation Choices (CFCLP-TC). The problem is based on a production network of two echelons with multiple plants, a set of potential distribution centers, and customers. The problem is formulated as an optimization model with two o...

This paper presents various instances using an Integer Linear Programming model that consider the institutional rules of the UPAEP University. This problem mainly arises in the allocation design of many known variables, such as courses with professors previously assigned, rooms and timeslots. Also availability and capacity rooms are considered. In...

Additive manufacturing is an emerging technology that brings several opportunities to the manufacturing industry. Therefore, research in this arena on current and future developments is required to make strategic decisions. Under this context, the goal of this research is to develop a patent analysis on additive manufacturing. Keyword-patent analys...

La complejidad en la administración de las cadenas de suministro ha significado que varias empresas no cuenten con todos los recursos y capacidades para alcanzar los cambios necesarios por sí mismas. Por tal motivo, este estudio plantea preguntas de investigación con relación a la presencia de proveedores de servicios logísticos para las empresas e...

In recent years thefts in the Mexican trucking sector have increased, causing huge losses to carriers, so a study to know the risk factors faced by the motor carriers seems pertinent. Security is a relatively recent topic in logistics and supply chain studies, mainly based on conceptual views and qualitative data on operational disruptions in the s...

This paper addresses a supply chain design problem based on a two-echelon single-product system. In the first echelon the plants transport the product to distribution centers. In the second echelon the distribution centers transport the product to the customers. Several transportation channels are available between nodes in each echelon, with diffe...

This paper reviews the problem of designing a multi-objective supply chain called Capacitated Fixed Cost Facility Location Problem with Transportation Choices (CFCLP-TC). We solve this multi-objective problem using the epsilon-constraint approach. The models with and without this transshipment feature are implemented in GAMS and solved with CPLEX.

This work solves a problem for PET pickup for recycling in the city of Obregón. The pickup points are schools and business with time windows constraints. The objectives are to minimize the transportation costs and the number of routes, and to maximize the utilization of the vehicles. A mathematical programming model of the vehicle routing problem w...

En México el robo se ha convertido en uno de los riesgos más relevantes para la eficiencia y la competitividad de las cadenas de suministro. Esta propuesta busca identificar las variables que influyen sobre el riesgo de robo en el autotransporte como paso previo de una metodología para evaluar cuantitativamente la influencia de las variables identi...

The artificial vision allows us to reduce a problem by means of techniques that have obeyed the study of the intelligence of living systems. A well-known technique is data mining and pattern recognition, which are disciplines dependent of artificial intelligence that from some data, allow the acquisition of knowledge and in particular, within data...

A supply chain design problem based on a two-echelon single-product system is addressed. The product is distributed from plants to distribution centers and then to customers. There are several transportation channels available for each pair of facilities between echelons. These transportation channels introduce a cost–time tradeoff in the problem t...

This paper reviews the problem of designing a multi-objective supply chain called Capacitated Fixed Cost Facility Location Problem with Transportation Choices (CFCLP-TC). The problem is formulated as a bi-objective optimization model with objective functions based on cost and time. The problem has two-echelons with plants that supply to distributio...

Entre las metodologías utilizadas en el particionamiento territorial, destacan los modelos de localización-asignación (“location-allocation”) y los de particionamiento de conjuntos ("set partitioning”), que agrupan pequeñas áreas geográficas llamadas unidades básicas en un número dado de grupos geográficos más grandes, denominados territorios. El p...

Among methodologies used in territory clustering, stand locationallocation and set partitioning models, to group small geographic areas, usually called “basic units” into a given number of larger groups called “territories”. The territory clustering problem is modeled as a p-median problem. A Lagrangean relaxation is used to obtain lower bounds to...

As part of the process to support decision making in population problems, with the aim of promoting the selection of projects with funding support for the sector of the economically inactive population, in this paper a custom multi-objective method was applied to produce a set of efficient solutions that correspond to the selection of the best grou...

Designing and updating of sales territories are strategic activities that have several causes like mergers and changes in the markets among others. The new territories must satisfy the planning characteristics defined by each company. In this paper we propose a biobjective mixed integer programming model for redesigning sales territories. The study...

This work presents a case of study for the calculation of the parameters for inventory control for 6219 products being handled by the Distribution Centers (DCs) of a company that distributes engines and spare parts in Mexico. The analysis was carried out in one of the four business units in which this company is divided. This unit has two DCs in th...

The appropriate redesign of sales territories is a key element to increase the sales and minimize costs. So, it becomes a common practice to be motivated by mergers and changes in a market in constant motion. This paper presents and describes a two-stage heuristic bi-objective to redesign sales territories inspired by a real problem for a company t...

This work reexamines a supply chain design problem called the Capacitated Fixed Cost Facility Location Problem with Transportation Choices (CFCLP-TC). The problem was formulated as a bi-objective optimization model with objective functions based on time and cost. The problem has two echelons with plants serving distribution centers and these servin...

This work shows the service of students of Tecnologico de Monterrey for the NGO "Juntos por el Camino de la Esperanza, A.C." based in Aguascalientes, Mexico. The organization provides psychological and legal support for the patients of terminal cancer treatment, and their families. The problem was to route the available vehicles to pick up and retu...