Product Return Handling

In this article we focus on product return handling and warehousingissues. In some businesses return rates can be well over 20% andreturns can be especially costly when not handled properly. In spiteof this, many managers have handled returns extemporarily. The factthat quantitative methods barely exist to support return handlingdecisions adds to this. In this article we bridge those issues by 1)going over the key decisions related with return handling; 2)identifying quantitative models to support those decisions.Furthermore, we provide insights on directions for future research.reverse logistics;decision-making;quantitative models;retailing and warehousing

Integrated Models and Tools for Design and Management of Global Supply Chain

In modern and global supply chain, the increasing trend toward product variety, level of service, short delivery delay and response time to consumers, highlight the importance to set and configure smooth and efficient logistic processes and operations. In order to comply such purposes the supply chain management (SCM) theory entails a wide set of models, algorithms, procedure, tools and best practices for the design, the management and control of articulated supply chain networks and logistics nodes. The purpose of this Ph.D. dissertation is going in detail on the principle aspects and concerns of supply chain network and warehousing systems, by proposing and illustrating useful methods, procedures and support-decision tools for the design and management of real instance applications, such those currently face by enterprises. In particular, after a comprehensive literature review of the principal warehousing issues and entities, the manuscript focuses on design top-down procedure for both less-than-unit-load OPS and unit-load storage systems. For both, decision-support software platforms are illustrated as useful tools to address the optimization of the warehousing performances and efficiency metrics. The development of such interfaces enables to test the effectiveness of the proposed hierarchical top-down procedure with huge real case studies, taken by industry applications. Whether the large part of the manuscript deals with micro concerns of warehousing nodes, also macro issues and aspects related to the planning, design, and management of the whole supply chain are enquired and discussed. The integration of macro criticalities, such as the design of the supply chain infrastructure and the placement of the logistic nodes, with micro concerns, such the design of warehousing nodes and the management of material handling, is addressed through the definition of integrated models and procedures, involving the overall supply chain and the whole product life cycle. A new integrated perspective should be applied in study and planning of global supply chains. Each aspect of the reality influences the others. Each product consumed by a customer tells a story, made by activities, transformations, handling, processes, traveling around the world. Each step of this story accounts costs, time, resources exploitation, labor, waste, pollution. The economical and environmental sustainability of the modern global supply chain is the challenge to face

Evaluating the benefits of picking and packing planning integration in e-commerce warehouses

Motivated by recent claims on the potential value of integration in warehouse management, this study evaluates the benefits arising from integrating the planning of order picking and packing processes in e-commerce warehouses. A set of research questions are proposed for exploring various benefits under different operational conditions and an experimental study is designed to answer them. In order to have a concrete model to represent the integrated planning method, a mixed-integer nonlinear programming model is developed, and then compared against a non-integrated variation. The experimental study makes the comparisons by analysing the collected empirical data from a real-life warehouse. Our findings indicate that integrated picking and packing planning can yield improved performance in different aspects under different configurations of objectives, order quantities, order categories or workforce allocation

Evaluating the benefits of picking and packing planning integration in e-commerce warehouses

Motivated by recent claims on the potential value of integration in warehouse management, this study evaluates the benefits arising from integrating the planning of order picking and packing processes in e-commerce warehouses. A set of research questions are proposed for exploring various benefits under different operational conditions and an experimental study is designed to answer them. In order to have a concrete model to represent the integrated planning method, a mixed-integer nonlinear programming model is developed, and then compared against a non-integrated variation. The experimental study makes the comparisons by analysing the collected empirical data from a real-life warehouse. Our findings indicate that integrated picking and packing planning can yield improved performance in different aspects under different configurations of objectives, order quantities, order categories or workforce allocation

Material handling optimization in warehousing operations

Tableau d’honneur de la Faculté des études supérieures et postdoctorales, 2018-2019.Les activités de distribution et d’entreposage sont des piliers importants de la chaîne d’approvisionnement. Ils assurent la stabilité du flux de matières et la synchronisation de toutes les parties prenantes du réseau. Un centre de distribution (CD) agit comme un point de découplage entre l’approvisionnement, la production et les ventes. La distribution comprend un large éventail d’activités visant à assurer la satisfaction de la demande. Ces activités passent de la réception au stockage des produits finis ou semi-finis, à la préparation des commandes et à la livraison. Les opérations d’un CD sont maintenant perçues comme des facteurs critiques d’amélioration. Elles sont responsables de la satisfaction d’un marché en évolution, exigeant des délais de livraison toujours plus rapides et plus fiables, des commandes exactes et des produits hautement personnalisés. C’est pourquoi la recherche en gestion des opérations met beaucoup d’efforts sur le problème de gestion des CDs. Depuis plusieurs années, nous avons connu de fortes avancées en matière d’entreposage et de préparation de commandes. L’activité de préparation de commandes est le processus consistant à récupérer les articles à leur emplacement de stockage afin d’assembler des commandes. Ce problème a souvent été résolu comme une variante du problème du voyageur de commerce, où l’opérateur se déplace à travers les allées de l’entrepôt. Cependant, les entrepôts modernes comportent de plus en plus de familles de produits ayant des caractéristiques très particulières rendant les méthodes conventionnelles moins adéquates. Le premier volet de cette thèse par articles présente deux importants et complexes problèmes de manutention des produits lors de la préparation des commandes. Le problème de préparation des commandes a été largement étudié dans la littérature au cours des dernières décennies. Notre recherche élargit le spectre de ce problème en incluant un ensemble de caractéristiques associées aux installations physiques de la zone de prélèvement, comme les allées étroites, et aux caractéristiques des produits (poids, volume, catégorie, fragilité, etc.). Une perspective plus appliquée à la réalité des opérations est utilisée dans notre développement d’algorithmes. Les déplacements liés à la préparation des commandes sont fortement influencés par le positionnement des produits. La position des produits dans la zone de prélèvement est déterminée par une stratégie d’affectation de stockage (storage assignment strategy). Beaucoup de ces stratégies utilisent de l’information sur les ventes des produits afin de faciliter l’accès aux plus populaires. Dans l’environnement concurrentiel d’aujourd’hui, la durée de vie rentable d’un produit peut être relativement courte. Des promotions peuvent également être faites pour pousser différents produits sur le marché. Le positionnement fourni par la stratégie d’hier ne sera probablement plus optimal aujourd’hui. Il existe plusieurs études mesurant l’impact d’une bonne réaffectation de produits sur les opérations de prélèvement. Cependant, ils étudient la différence des performances avec les positionnements passés et actuels. La littérature démontre clairement que cela apporte des avantages en termes d’efficacité. Toutefois, les déplacements nécessaires pour passer d’une position à une autre peuvent constituer une activité très exigeante. Ceci constitue le second volet de cette thèse qui présente des avancées intéressantes sur le problème de repositionnement des produits dans la zone de prélèvement. Nous présentons le problème de repositionnement des produits sous une forme encore peu étudiée aux meilleurs de nos connaissances : le problème de repositionnement. Plus précisément, nous étudions la charge de travail requise pour passer d’une configuration à l’autre. Cette thèse est structuré comme suit. L’introduction présente les caractéristiques et les missions d’un système de distribution. Le chapitre 1 fournit un survol de la littérature sur les principales fonctions d’un centre de distribution et met l’accent sur la préparation des commandes et les décisions qui affectent cette opération. Le chapitre 2 est consacré à l’étude d’un problème de préparation de commandes en allées étroites avec des équipements de manutention contraignants. Dans le chapitre 3, nous étudions un problème de préparation des commandes où les caractéristiques des produits limitent fortement les routes de prélèvement. Le chapitre 4 présente une variante du problème de repositionnement (reassignment) avec une formulation originale pour le résoudre. La conclusion suit et résume les principales contributions de cette thèse. Mots clés : Préparation des commandes, entreposage, problèmes de routage, algorithmes exacts et heuristiques, réaffectation des produits, manutention.Distribution and warehousing activities are important pillars to an effective supply chain. They ensure the regulation of the operational flow and the synchronization of all actors in the network. Hence, distribution centers (DCs) act as crossover points between the supply, the production and the demand. The distribution includes a wide range of activities to ensure the integrity of the demand satisfaction. These activities range from the reception and storage of finished or semi-finished products to the preparation of orders and delivery. Distribution has been long seen as an operation with no or low added value; this has changed, and nowadays it is perceived as one of the critical areas for improvement. These activities are responsible for the satisfaction of an evolving market, requiring ever faster and more reliable delivery times, exact orders and highly customized products. This leads to an increased research interest on operations management focused on warehousing. For several years, we have witnessed strong advances in warehousing and order picking operations. The order picking activity is the process of retrieving items within the storage locations for the purpose of fulfilling orders. This problem has long been solved as a variant of the travelling salesman problem, where the order picker moves through aisles. However, modern warehouses with more and more product families may have special characteristics that make conventional methods irrelevant or inefficient. The first part of this thesis presents two practical and challenging material handling problems for the order picking within DCs. Since there are many research axes in the field of warehousing operations, we concentrated our efforts on the order picking problem and the repositioning of the products within the picking area. The order picking problem has been intensively studied in the literature. Our research widens the spectrum of this problem by including a set of characteristics associated with the physical facilities of the picking area and characteristics of the product, such as its weight, volume, category, fragility, etc. This means that a more applied perspective on the reality of operations is used in our algorithms development. The order picking workload is strongly influenced by the positioning of the products. The position of products within the picking area is determined by a storage assignment strategy. Many of these strategies use product sales information in order to facilitate access to the most popular items. In today’s competitive environment, the profitable lifetime of a product can be relatively short. The positioning provided by yesterday’s assignment is likely not the optimal one in the near future. There are several studies measuring the impact of a good reassignment of products on the picking operations. However, they study the difference between the two states of systems on the picking time. It is clear that this brings benefits. However, moving from one position to another is a very workload demanding activity. This constitutes the second part of this thesis which presents interesting advances on the repositioning of products within the picking area. We introduce the repositioning problem as an innovative way of improving performance, in what we call the reassignment problem. More specifically, we study the workload required to move from one setup to the next. This thesis is structured as follows. The introduction presents the characteristics and missions of a distribution system. Chapter 1 presents an overview of the literature on the main functions of a DC and emphasizes on order picking and decisions affecting this operation. Chapter 2 is devoted to the study of a picking problem with narrow aisles facilities and binding material handling equipment. In Chapter 3, we study the picking problem with a set of product features that strongly constrain the picking sequence. Chapter 4 presents a variant of the reassignment problem with a strong and new formulation to solve it. The conclusion follows and summarizes the main contributions of this thesis. Key words: Order-picking, warehousing, routing problems, exact and heuristic algorithms, products reassignment, material handling

A storage assignment simulation model for optimizing processes in an e-commerce warehouse of a fashion supply chain

The wide spread of e-commerce and in general B2C systems brought new challenges to supply chains which had to reconsider part of their systems whilst maintaining the same goal: a high level of customer satisfaction. One of the main functions affected by these challenges is the logistics activity, including warehouse management and transports. Indeed, they now have to face higher orders at the same time, to manage picks demand in specified periods, to increase journeys for reaching various customers geographically dispersed. Optimization and synchronization are essential. To this end and according to the steps of the Deming Cycle, this paper presents the case of a warehouse located in northern Italy whose storage activity was firstly simulated and then successfully implemented so as to optimize the picking activity and consequently the subsequent processes of the outbound flow. Improvements were assessed through determined key performance indicators, monitored before and after the implementation of the new strategy

Cross-Functional Maintenance And Logistics Business Process Integration: Lessons From A Large Oil And Gas Company

The purpose of this research focused on integration and alignment of maintenance and logistics functions in a large ERP system in an oil and gas company to demonstrate how cross-functional integration can improve operations. A design science approach has been used based on a case study of a large oil and gas company. The study found that limited cross-functional integration involving the logistics function exists. Proposed process redesign involves activities include improved storage and picking strategies, information exchange, notification of fully received components at the warehouse and an improved shipping strategy. These improvement strategies have been tested through random questionnaires and most respondents support the improvements. This study shows that business process improvement facilitated by cross-functional process integration should realise substantial financial benefits. We have shown that warehouse operation strategies do have an impact on the work order performance through the on-time delivery of its components. In addition, regular communication and utilisation of the available information can also improve the scheduling of work order execution. These benefits are not limited to the company in question but the results show that if companies in general give more attention to cross-functional integration, substantial benefits are possible. The focus of this study is uncommon as it is the integration of logistics and maintenance functions within an organisation. We show substantial process improvements are possible. It therefore provides another opportunity for business process improvement experts to better align various systems and processes