ALEJANDRA GOMEZ PADILLA - Academia.edu (original) (raw)

Papers by ALEJANDRA GOMEZ PADILLA

HAL (Le Centre pour la Communication Scientifique Directe), Apr 3, 2006

International audienceCette communication analyse l'influence que peuvent avoir les condition... more International audienceCette communication analyse l'influence que peuvent avoir les conditions contractuelles inter-entreprises sur la coordination des flux physiques dans les chaînes logistiques. Notre travail propose une modélisation d'une relation verticale stylisée entre deux entreprises qui interagissent via des flux physiques de produits et des transferts monétaires. Sur la base d'un modèle de vendeur de journaux, dans un contexte de demande aléatoire avec ventes perdues et stockage des invendus, nous montrons que la coordination des décisions prises par chaque entreprise dans une chaîne logistique est tributaire des modalités des transferts monétaires entre les acteurs. Si le contrat classique de « prix de gros » ne permet pas une coordination efficace (au sens d'une maximisation de la valeur globale de la chaîne), nous proposons des variantes qui peuvent améliorer significativement les performances des entreprises et atteindre une optimisation globale. Ainsi, un contrat intégrant le partage des coûts de stockage des invendus entre les deux acteurs de la chaîne logistique permet de répartir les risques tout en améliorant la satisfaction de clients finaux. Nous montrons également l'importance de la prise en compte des modalités contractuelles dans la détermination des niveaux de recomplètement, ou plus généralement dans les décisions en matière d'approvisionnement.

Ce travail de these porte sur les relations entre deux entreprises liees verticalement : un fourn... more Ce travail de these porte sur les relations entre deux entreprises liees verticalement : un fournisseur (FO) et un donneur d'ordres (DO), qui vont pouvoir se coordonner a travers la prise de decisions logistiques, liees aux flux physiques, qui visent a minimiser les couts en agissant sur les stocks detenus et les quantites de reapprovisionnement, et de decisions economiques, liees aux flux financiers, qui visent a maximiser le benefice de chaque acteur en agissant sur les parametres contractuels et les prix. L'objectif de notre travail est de modeliser et d'evaluer les decisions de chaque acteur, pour un chaque contrat etudie. Les contrats sont les contrats de prix de gros, rabais, quantite flexible, rachat, partage de revenu et reservation de capacite. Il s'agit d'etudier si le contrat modelise permet de coordonner efficacement la chaine, c'est-a-dire, s'il maximise simultanement les profits de chaque acteur et de la chaine. L'etude des contrats a ete faite de facon a ameliorer le profit du FO par rapport a un contrat de prix de gros. La variable de decision du DO est le niveau de recompletement et les variables de decision du FO sont liees aux parametres du contrat, qu'il propose au DO afin de l'inciter a commander davantage et d'ameliorer ainsi son profit. Nous avons mis en evidence l'importance du contrat dans la determination des profits individuels, dans la politique de recompletement du DO et dans la strategie contractuelle du FO. Nous pouvons alors comparer les differents contrats par rapport a une situation d'optimisation globale de la chaine.

Journal of Industrial Engineering and Management, Oct 26, 2017

Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch ge... more Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden. Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen. Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte. Terms of use: Documents in EconStor may be saved and copied for your personal and scholarly purposes. You are not to copy documents for public or commercial purposes, to exhibit the documents publicly, to make them publicly available on the internet, or to distribute or otherwise use the documents in public.

European Journal of Contemporary Education, Mar 15, 2021

This paper proposes the production of animated comics in POWTOON to serve as a visual collaborati... more This paper proposes the production of animated comics in POWTOON to serve as a visual collaborative tool and a teaching-learning strategy for a course on Operations Research. This proposal aims to achieve meaningful learning of the subject matter, incentivizing the creativity of undergraduate students of marketing and business at the Guadalajara University, given that the production of comics develops, in students, cognitive and practical abilities such as the following: reflection; critical thinking; observation; analysis; synthesis; analogy; systematization; a sense of collaboration; and, teamwork. To validate the substantial improvement in student performance after producing the comic, a paired two-sample means t-test was carried out for 35 undergraduate students of marketing and business at the Guadalajara University who were enrolled in the same Operations Research course. The results obtained show that student performance improved considerably after the production of the comics, facilitating both teaching and the students' significant learning. In this sense, the use of POWTOON demonstrated to be a good learning alternative, since the students for the realization of the comic were able to recover and review the information acquired, write a script, and organize images, videos, sounds, and text in a congruent and didactic way, even when it comes to complex topics.

Maritime Economics & Logistics, 2020

We propose an option contract model for the leasing of containers. In an option contract, the shi... more We propose an option contract model for the leasing of containers. In an option contract, the shipping company commits to order a quantity of containers from the leasing company and has the right to modify its order at a later stage, according to its actual requirement. Under this scheme, the shipping company is allowed to request a smaller or larger number of containers than the agreed initial order. This is done by buying an option premium in advance from the container leasing company. We present numerical results for different scenarios based on information provided by experts in the industry. For the purposes of comparison, a nonoption contract scheme is also evaluated. According to our numerical results, an option contract is better under a scenario where demand is normally distributed with a large standard deviation. This scenario is commonly observed in practice due to the dynamism and volatility of the shipping industry. We conclude that, under an option contract scheme, the...

Expert Systems with Applications, 2021

This paper introduces the multi-depot open location routing problem (MD-OLRP) with a heterogeneou... more 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 contracting each vehicle and a variable cost associated with the distance traveled. The empty haul return to the vehicles depot is not considered in the cost. The raw materials collected are delivered to a single delivery point. The problem is modeled as a Mixed Integer Linear Program (MILP) that minimizes the total cost, selecting the carriers to be contracted, the vehicles to be used from each contracted carrier and the collection routes. For small instances, the model can be solved to optimality. However, approximate procedures are necessary to handle larger instances. In this sense, in the present work we propose an intelligent metaheuristic which incorporates problem specific knowledge to solve it. The computational results show that the solution method is computationally efficient and provides high quality solutions. In particular, the new solution obtained for the case of study generates savings of 30.86% to the company. The main contributions of the paper are the new problem statement that was not found in the literature, its association to the real problem of a company and the intelligent metaheuristic proposed to solve it. Additional experimentation used the model proposed to solve a simpler problem obtaining new best solutions compared to those reported in the recent literature.

Http Www Theses Fr, 2005

Brazilian Journal of Operations & Production Management, 2011

The objective of this document is to compare the performance of the companies forming a dyadic su... more The objective of this document is to compare the performance of the companies forming a dyadic supply chain, and for the chain as a single unit, under two types of contracts: option and rebate. The performance is measured in economic terms (benefits and costs) and in physical units (inventory held and unsatisfied demand). The results will help to identify which is the better contract for a given set of parameters. Under an option contract, the retailer orders a quantity of units and has a right to modify his order (increase or decrease) by buying the option premium in advance from the supplier. Under a rebate contract, the supplier offers a rebate for the units ordered over a certain number of units previously fixed. With an option contract, the retailer reserves a number of units from the supplier and, after receiving more information about demand, he will pass his final order. With a rebate contract, the retailer will decide from the beginning the number of units to order knowing the rebate condition (price and quantity). First the theoretical bases are introduced for each contract, next both models are compared by simulation. The simulation plan is presented and the results are discussed.

Concepts for Effective Management

This chapter highlights the importance of contracts for coordination between companies in a suppl... more This chapter highlights the importance of contracts for coordination between companies in a supply chain. It considers a dyadic situation, with a supplier and a retailer. Coordination is achieved by two types of decisions: economic (concerning prices established and stated over a contract), and physical exchange of products (concerning the inventory that is going to be held by the retailer). First one contract with a simple pricing scheme is considered, and then two contracts with inventory holding cost shared among the companies of the supply chain. The former is presented to explain the general situation and the two last ones to explain different schemes of inventory cost share. A numerical example is also shown. The objective is to illustrate that a supply chain may be efficiently coordinated if the companies establish contracts with inventory holding cost share.

International Journal of Information Systems and Supply Chain Management, 2009

In this document it is analyzed the importance of contracts for coordination between two companie... more In this document it is analyzed the importance of contracts for coordination between two companies in a supply chain. In the studied situation, one company, or supplier, supplies one product to the other company, who is a retailer. The companies are going to coordinate by two types of decisions: economic (concerning prices fixed on a contract), and physical exchange (concerning the inventory to be held). Two types of contracts will be presented: one contract with a simple pricing scheme and two contracts with inventory holding cost shared among the companies of the supply chain. The objective is to show that contracts with inventory holding cost share allow the two companies to efficiently coordinate the chain they form.

International Journal of Industrial and Systems Engineering, 2013

This paper considers a dyadic supply chain formed by one retailer and one supplier, and compares ... more This paper considers a dyadic supply chain formed by one retailer and one supplier, and compares the performances for both companies and for the whole chain as a single unit under two types of contracts: option and capacity reservation contracts. Under an option contract, the retailer orders a quantity of units and has a right to modify his order in any sense (it may be bigger or smaller than the initial order), without restrictions by buying the option premium in advance from the supplier. Under a capacity reservation contract, the retailer reserves a number of units from the supplier and after receiving more information about demand, he will pass his final order. Firstly, the theoretical bases are introduced for each contract, next both models are compared, then simulation results are presented and discussed, and finally, we concluded.

DYNA INGENIERIA E INDUSTRIA, 2013

Un sistema de manejo y distribucion de alimentos en un banco de alimentos (BA) implica el acopio,... more Un sistema de manejo y distribucion de alimentos en un banco de alimentos (BA) implica el acopio, clasificacion (en buenas y malas condiciones de consumo), asignacion y distribucion del alimento a familias en pobreza. Nuestra investigacion forma parte de un proyecto de reingenieria del sistema de manejo-asignacion de alimento en un Banco de Alimentos (BA) de Mexico. El problema de configuracion de una dieta ha sido estudiado en la literatura principalmente con un enfoque en seleccionar las cantidades de alimento que minimicen el costo total de una dieta y satisfaciendo los requerimientos nutricionales especificados en la misma. En el contexto de una cadena de suministro, la asignacion del alimento a multiples familias implica extender este problema sujeto a restricciones nutricionales principalmente, a otro tipo de limitantes como: disponibilidad de recursos, asignacion de recursos a multiples puntos, restricciones de peso y volumen por uso de contenedores durante la distribucion y el costo de recuperacion del conjunto de productos entregados al cliente. Nuestro articulo presenta un modelo matematico de asignacion- empaque de alimentos para configurar simultaneamente multiples despensas personalizadas por familia, sujeto a restricciones nutricionales y logisticas. La contribucion de esta investigacion radica en considerar simultaneamente las caracteristicas y restricciones de tres problemas que han sido estudiados en la literatura de forma separada: el problema de asignacion limitada de recursos en una cadena de suministro, el problema de la dieta y el problema de empaque de alimentos. El modelo es planteado como un problema de programacion lineal entera-mixta y resuelto utilizando Lingo 13 ®. La validacion del modelo se realizo a traves de experimentos en diferentes escenarios de operacion utilizando la informacion proporcionada por el BA de Mexico. Se analiza el tiempo de busqueda de la solucion en cada escenario y se realiza un analisis estadistico no-parametrico comparando las caracteristicas nutricionales y dimensionales de las despensas obtenidas en cada escenario.

Annals of Operations Research, 2010

(http://matematicas.univalle. edu.co/~appopt2008/). The APPOPT conference series aims to bring to... more (http://matematicas.univalle. edu.co/~appopt2008/). The APPOPT conference series aims to bring together mathematicians, engineers, and other specialists from a variety of related disciplines, who are at the forefront of their research fields, to exchange original ideas and present high-quality scientific research related to the development of optimization and approximation theory, models, algorithms, and their applications to both theoretical and complex real-life problems. The numerous research papers presented at APPOPT-2008 included a significant amount of research that addressed both manufacturing-oriented and service-oriented problems. Submission to this special section was open to papers related to the topic but not necessary presented at the conference venue. Eleven papers, selected for the quality of both the abstract and the presentation, participated in the evaluation process for this special volume. Only four papers were finally accepted after completing the rigorous traditional peer-review process of the journal for scientific merit. These papers present applications of optimization techniques to solve realistic optimization problems.

Research Methodologies in Supply Chain Management

In this paper we present the methodology of research that has been the base of our work. The main... more In this paper we present the methodology of research that has been the base of our work. The main objective is to study contractual relations; this is the reason why we talk of a contract-oriented research methodology. Through bibliographical research, assistance to workshops and industrial contacts, we identified the basic elements that are the basic issues for understanding and describing a contractual relation. After explaining why we chose these elements, we will describe them as well as their characteristics. We also show how we describe a relation between an upstream and a downstream company. Then we present a mathematical model of this relationship.

Ingeniería, investigación y tecnología, 2017

Se programaron dos formulaciones para estudiar flujos de potencia para una red de transmisión. Se... more Se programaron dos formulaciones para estudiar flujos de potencia para una red de transmisión. Se consideran dos métodos: el de Newton-Rapshon incorporando restricciones de seguridad y el método de flujos óptimos con consideraciones económicas. Se muestra un ejemplo para una red eléctrica de prueba de 30 nodos con la que se comparan resultados. Descriptores: Flujos Óptimos (OPF), seguridad, estabilidad de voltaje.

This work focus mainly on a specific question: for an adopted contract, what are the decisions to... more This work focus mainly on a specific question: for an adopted contract, what are the decisions to be taken for each company taking into account his own interests, knowing that these decisions influence the behavior of the other company and in consequence the coordination of the chain. This may be also explained using the terms of Cachon (2004) who clearly presents this situation: “Optimal supply chain performance requires the execution of a precise set of actions. Unfortunately, those actions are not always in the best interest of the members in the supply chain, i.e., the supply chain members are primarily concerned with optimizing their own objectives, and that selfserving focus often results in poor performance. However, optimal performance can be achieved if the firms coordinate by contracting on a set of transfer payments such that each firm’s objective becomes aligned with the supply chain’s objective” (pp. 229). On recent years there has been a growing interest on the study o...