Distribution Warehouse Research Articles

Multi-attribute evaluation and selection of sites for agricultural product warehouses based on an Analytic Hierarchy Process

Site selection for companies is a complex and unstructured problem that must be analyzed carefully and properly, since a localization error could drive to bankrupt. This problem has been discussed widely and effectively using multi-attribute methods in a manufacturing context, but it has been little studied in agribusiness. The goal of this work is a methodological approach oriented to evaluate optimal locations of new agri-food warehouses. Furthermore, a literature review is developed, analyzing the location problem and the attributes and techniques most widely used applied to agribusiness, and a case-study is presented in order to exemplify the methodological proposal. The multi-attribute technique called Analytic Hierarchy Process has been selected as the basis for the research, and it is applied to the real case study analyzed: the selection of a site for a new banana distribution warehouse. Six generic criteria have been analyzed: accessibility to the area, distance, cost, security of the region, local acceptance of the company, and its needs. The process includes the assignment of attributes to each one of the generic criteria, as well as the assessment of their importance levels. Three different areas of Guadalajara, Jalisco, and Mexico DF have been evaluated for the case-study, and the methodological proposal has been utilized to determine the best option.

Organizing warehouse management

PurposeThe purpose of this paper is to investigate how warehouse management, understood as a cluster of planning and control decisions and procedures, is organized and driven by task complexity (TC) and market dynamics (MD).Design/methodology/approachA multi‐variable conceptual model is developed based on the literature and tested among 215 warehouses using a survey.FindingsThe results suggest that TC and MD are the main drivers of warehouse management, measured by planning extensiveness (PE), decision rules complexity, and control sophistication. Differences between production and distribution warehouses are found with respect to the relationship between assortment changes and PE. Furthermore, TC appears to be a main driver of the specificity of the warehouse management (information) system (WMS).Research limitations/implicationsThis paper is based on 215 warehouses in The Netherlands and Flanders (Belgium); future research may test the model on a different sample. More research should be conducted to further validate the measures of the core dimensions of warehouse management.Practical implicationsDifferent levels of TC and MD characterize warehouses. Such a characterization is a first step in determining generic warehouse functionalities and helping managers to decide on the best software for their warehouse operations.Originality/valueThe paper defines the core dimensions of warehouse management, makes them measurable, tests them and assesses how these drivers impact specificity of WMS. The paper shows that PE in production warehouses is driven by different variables than in distribution centers.

A dynamic inventory model with supplier selection in a serial supply chain structure

Considering the inherent connection between supplier selection and inventory management in supply chain networks, this article presents a multi-period inventory lot-sizing model for a single product in a serial supply chain, where raw materials are purchased from multiple suppliers at the first stage and external demand occurs at the last stage. The demand is known and may change from period to period. The stages of this production–distribution serial structure correspond to inventory locations. The first two stages stand for storage areas for raw materials and finished products in a manufacturing facility, and the remaining stages symbolize distribution centers or warehouses that take the product closer to customers. The problem is modeled as a time-expanded transshipment network, which is defined by the nodes and arcs that can be reached by feasible material flows. A mixed integer nonlinear programming model is developed to determine an optimal inventory policy that coordinates the transfer of materials between consecutive stages of the supply chain from period to period while properly placing purchasing orders to selected suppliers and satisfying customer demand on time. The proposed model minimizes the total variable cost, including purchasing, production, inventory, and transportation costs. The model can be linearized for certain types of cost structures. In addition, two continuous and concave approximations of the transportation cost function are provided to simplify the model and reduce its computational time.

Supportive Role of Dynamic Order Picking Area in Distribution Warehouse

Paper contains discussion about selected aspects of order picking systems in distribution warehouse and supportive role of dynamic order picking. The definitions and characteristics of static and dynamic order picking processes are given to compare these processes and determine rules for setting them in distributional warehouse. Warehouse activity profiling is presented in terms of assigning skus into dynamic and static order picking areas. The process of dynamic order picking is described and formally denoted. The simulation approach allowing investigation of dynamic order picking area is presented and used to obtain experimental data. Results are discussed. 1

Study of the transferability of properties used for designing production systems layouts to distribution warehouse layout design

The performance of distribution warehouses plays an important role in the global performance of any Supply Chain. Logistic services providers need to plan the layout evolution of the physical system they manage to adapt to their customers' requests. A clear, global and detailed vision of logistic activities is therefore necessary. A considerable amount of research has been conducted on the design of production systems. This article proposes a study of the transferability of certain production system design properties to distribution warehouse design.

Benefits and limitations of the SCOR model in warehousing

In the Supply Chain, the flows of goods are the result of exchanges between two major parties: the manufacturer / industrial company / supplier on the one hand and the distributor / customer on the other. There are many intermediaries between these two parties who, depending on the nature of the service provided, can be classified as 3PL (Third-Party Logistics provider) or 4PL (4th-Party Logistics Provider). This paper focuses on the 3PL provider. A 3PL provider is a logistic services provider of the Supply Chain responsible for implementing all or part of their customers' logistics. This form of subcontracting concerns warehouse management and transport activities as well as all associated services such as co-packing. The objective of subcontracting is to improve the performance of the logistical process. Modelling and evaluating the performance of these processes helps improve the performance of the Supply Chain. SCOR model (Supply Chain Operations Reference), proposed by the Supply Chain Council, gives a modelling and an evaluation of the performance in Supply Chain. In the context of 3PL, the objective of this paper is to identify the benefits and limitations of the SCOR. The study is illustrated by a distribution warehouse case in an international logistic services provider.

Replenishment policies for warehouse systems under cyclic demand

This paper takes up the study of a distribution warehouse at the downstream end of a supply chain, from where the off-take of the product takes place. We study the behaviour of the warehouse system, in a discrete time-frame, for cyclical demand variations, and investigate its behaviour under different types of ordering/replenishment policies, and under practically achievable lags. Analytical solutions are obtained which provide good insights into the inherent characteristics of such replenishment policies. The last type of policy, of the moving average type, is shown to have superior performance characteristics compared to the other and conventional types.

« Le nez dans le micro ». Répercussions du travail sous commande vocale dans les entrepôts de la grande distribution alimentaire

Dans les entrepots de la grande distribution alimentaire, l’introduction d’un nouvel outil de travail, le guidage par commande vocale, a considerablement modifie le travail des preparateurs de commande. Auparavant caracterisee par l’absence d’enchainement et la possibilite de prendre de l’avance, l’activite de preparation a evolue vers une temporalite restrictive comparable a celle d’un ouvrier sur chaine. Sous guidage vocal, « le nez dans le micro », le savoir-faire des preparateurs est reduit a un engagement physique. L’usage du corps constitue alors une ressource en tant mode d’appropriation du sens au travail, mais egalement un rempart lorsque des pathologies font apparaitre les limites de l’intensification.

METAHEURISTIC APPROACH FOR THE MULTI-DEPOT VEHICLE ROUTING PROBLEM

Distribution logistics comprises all activities related to the provision of finished products and merchandise to a customer. The focal point of distribution logistics is the shipment of goods from the manufacturer to the consumer. The products can be delivered to a customer directly either from the production facility or from the trader's stock located close to the production site or, probably, via additional regional distribution warehouses. These kinds of distribution logistics are mathematically represented as a vehicle routing problem (VRP), a well-known nondeterministic polynomial time (NP)-hard problem of operations research. VRP is more suited for applications having one warehouse. In reality, however, many companies and industries possess more than one distribution warehouse. These kinds of problems can be solved with an extension of VRP called multi-depot VRP (MDVRP). MDVRP is an NP-hard and combinatorial optimization problem. MDVRP is an important and challenging problem in logistics management. It can be solved using a search algorithm or metaheuristic and can be viewed as searching for the best element in a set of discrete items. In this article, cluster first and route second methodology is adapted and metaheuristics genetic algorithms (GA) and particle swarm optimization (PSO) are used to solve MDVRP. A hybrid particle swarm optimization (HPSO) for solving MDVRP is also proposed. In HPSO, the initial particles are generated based on the k-means clustering and nearest neighbor heuristic (NNH). The particles are decoded into clusters and multiple routes are generated within the clusters. The 2-opt local search heuristic is used for optimizing the routes obtained; then the results are compared with GA and PSO for randomly generated problem instances. The home delivery pharmacy program and waste-collection problem are considered as case studies in this paper. The algorithm is implemented using MATLAB 7.0.1.

Development and evaluation of an integrated emergency response facility location model

Purpose: The purpose of this paper is to propose and compare the performance of the “two” robust mathematical models, the Robust Integer Facility Location (RIFL) and the Robust Continuous Facility Location (RCFL) models, to solve the emergency response facility and transportation problems in terms of the total logistics cost and robustness. Design/methodology/approach: The emergency response facilities include distribution warehouses (DWH) where relief goods are stored, commodity distribution points (CDP), and neighborhood locations. Authors propose two robust models: the Robust Integer Facility Location (RIFL) model where the demand of a CDP is covered by a main DWH or a backup CDP; the Robust Continuous Facility Location (RCFL) model where that of a CDP is covered by multiple DWHs. The performance of these models is compared with each other and to the Regular Facility Location (RFL) model where a CDP is covered by one main DWH. The case studies with multiple scenarios are analyzed. Findings: The results illustrate that the RFL outperforms others under normal conditions while the RCFL outperforms others under the emergency conditions. Overall, the total logistics cost and robustness level of the RCFL outperforms those of other models while the performance of RFL and RIFL is mixed between the cost and robustness index. Originality/value: Two new emergency distribution approaches are modeled, and evaluated using case studies. In addition to the total logistics cost, the robustness index is uniquely presented and applied. The proposed models and robustness concept are hoped to shed light to the future works in the field of disaster logistics management.

Tabu search heuristics for the order batching problem in manual order picking systems

In a manual order picking system, order pickers walk or ride through a distribution warehouse in order to collect items requested by (internal or external) customers. In order to perform these operations efficiently, it is usually required that customer orders be combined into (more substantial) picking orders that are limited in size. The order batching problem considered in this paper deals with the question of how a given set of customer orders should be combined into picking orders such that the total length of all picker tours necessary for all of the requested items to be collected is minimized. For the solution of this problem the authors suggest two approaches based on the tabu search principle. The first is a (classic) tabu search (TS), and the second is the attribute-based hill climber (ABHC). In a series of extensive numerical experiments, these approaches are benchmarked against other solution methods put forward in the current literature. It is demonstrated that the proposed methods are superior to the existing methods and provide solutions which may allow distribution warehouses to operate more efficiently.

Designing a distribution network with uncertainty demands and costs

This paper addresses a distribution network design problem in a 3-echelon supply chain subjected to uncertainty in the input data at strategic planning. It uses a basic model formulated as mixed-integer programming (MIP) that involves in locating production plants and distribution warehouse, and determines the best strategy for distributing the product from plants to the warehouse and from the warehouse to customers. These strategic decisions affect the efficiency and effectiveness of the designed system over the implementation time; thus, it seems necessary for the decision makers to build a real-world model at this level of planning. The study is faced with the uncertainty in many decision parameters, such as customer demands and costs. Thus, this study uses two uncertain problem-solving approaches, namely robust optimization and interval linear programming, for the basic model presented by Amiri (2006). The first approach generates a series of solutions that are progressively less sensitive to realization of the input data from a set of scenarios. Its main goal is to select the optimum numbers of locations and capacities of plants and warehouses, so that the total cost of the distribution network is minimized under different economic growth scenarios. Furthermore, this study uses interval linear programming to consider uncertainty in the distribution network. Thus, the basic MIP model is now developed into two models, namely robust optimization and interval linear programming). Finally, the Amiri’s model is also solved by the optimization software along with the two forgoing developed models. To show their efficiency, the related results are compared and illustrated. It is concluded that the results obtained by robust optimization are superior to the results reported by interval linear programming and the Amiri’s model. Key words: Distribution network, supply chain, uncertainty, robust optimization, interval linear programming.

Current State and Rational Management of the Distribution Warehouses of Enterprises in Asia and Europe

재화(Goods)의 생산(production)은 소비(consumption)를 목적으로 한다. 「국부론」(An inquirt into the nature and causes of the wealth of nations 1776)의 저자 Adam Smith가 동 저서에서 “소비는 최종단계이고 모든 생산의 목적이다.” (Consmption is the sole end and purpose of all production) 라고 했듯이, 특수한 경우를 제외하고는 다소의 차이는 있겠지만 재화의 공간적 이동(Spacial Movement)과 시간적 이동(Time movement)으로 이루어지며 공간적 이동은 운반과 운송(Transport)으 로 나타나고 시간적 이동은 보관(Storage)의 형태로 나타난다. 시간적 이동은 재화의 현상을 지속하고 보전을 목적으로 하지만 재화의 종류별로 화학적 변화를 목적으로 하기로 한다. 재화의 존재를 유지하는 방법을 나무상자, 유리, 종이 주머니 등을 사용할 수 있고 물자의 생활의 향상과 발전에 있어서 재화량 의 증가를 반감시키는 도난, 수해, 수난 또는 변질을 방지하기 위한 주거설비나 공장물 소위 창고 (warehouse)가 출현 한 것이다. 창고 즉 물적유통을 일컬어서 P.F.Drucker교수는 “경제학에 있어서의 아프리카대륙” 또는 기업이 취 하여야 할 “제3의 이윤원”이라 할 정도로 이에 대한 표현을 각종의 미사여구로 찬사를 아끼지 않았다, 그도 그럴 것이 현대에 있어서 이 분야의 중요성은 날이 갈수록 더해가고 있는 실정이며 이에 대한 관심 의 표명자가 눈에 띄게 늘어나고 있다. 이는 오늘날의 기업이 원재료의 절감은 가격경쟁을 지양하고 품질경쟁으로의 국가경쟁력을 압도하려는 기업의 전략에 차질이 생기게 하며 노무비의 절감은 종업원의 사기저하, 노사분규의 조장 우려, 생산 성 저하 등으로 이어질 가능성이 있으며 관리비의 절감은 오늘날 기업의 대명제인 목표관리(MBO) 실 현을 원만히 수행하기 위해서는 상위자가 일방적으로 예산과 비용의 억제는 종용할 수가 없으며 기업이 그 구성원들로부터 거래하는 것은 어디까지나 관리에 대한 결과이지 원인과 과정을 통제(management by control)할 수 없는 입장이다. 여기서는 유일하게 으로 포착할 수 있는 부분이 소위 이윤원로써 포착 할 수 있는 물류분야로써 수송, 하역, 보관, 포장, 유통가공, 정보 등의 제 분과가 있는데 특히 본고에서 는 경영학의 고도로 남아있는 보관 즉 창고업에 대해서 필을 들었다. 이 분야는 체계적인 학문적 이론이 전무하고 연구의도가 없으며 실무에서도 주먹구구식으로 경영을 해오고 있는 것이 실상이어서 이에 대 한 필요성도 느끼지 않을 만큼 답보상태에 있다. 앞으로 이에 대한 연구가 활발히 진행되어야 겠다는 생 각 하에서 그의 활성화 방안의 일환으로 물류창고를 중심으로 고찰했다. 물류창고의 정의(definition of warehouse)는 아직 확정된 것은 아니지만 일반적으로 물품을 저장 또는 보관하는 장소를 의미한다. 그런 의미에서 4개의 창고를 예를 들어서 정의를 내릴 수 있으니 자가창고, 영업창고, 공유(公有)창고, 임대창고를 들 수 있다. 이 분류와 이들 창고에 대한 것을 차례로 조사하겠지 만 일반적 정의는 창고에 속하는 기업에 한해서 규정된 것이고 일정 불변한 것은 아니다. 자가창고는 물자(Materials, parts, products, merchandise)를 손모, 품질저하, 멸실 하지않고 안전하게 저장, 보관, 재고관리, 수요공급을 조절하고 생산활동, 판매활동, 소비활동을 도와주는 건물, 공작물, 토 지, 지중(地中), 수면, 수중, 공중을 말한다. 영업창고는 물품의 멸실, 또는 손상을 방지하기 위한 공작물, 또는 물품의 멸실 또는 손상을 방지하기 위한 토지 또는 수면이기도 하고 물품보관에 제공되는 것을 말한다. 공유(公有)창고는 관공서 또는 그것에 준하는 공공기업체가 물자를 공익을 목적으로 저장, 보관하는 건조물, 공작물, 토지, 지중(地中), 수면, 수중, 공중으로 일컬을 수 있다. 임대창고는 영업창고업자이외의 기업체나 개인 소유의 건조물, 공작물을 임대료를 받고 다음 기업체 나 개인에게 물자를 저장, 보관할 목적으로 제공되는 건조물이나 공작물을 말하며 기업 물류분야에서는 물류거점시설인 물류센터인 창고가 차지하는 비중이 날로 증대되고 있다. 물류서비스에 대한 평가가 단 순 수송에 따른 공간적 이동에 의한 부가가치를 창출하는데 비해 공급의 시간적 조절, 수요패턴에 대한 대응력증진, 공급관리 등을 통한 공급의 질적 향상 등에 따른 기대효과가 커지고 있다. 국내의 경제활동 은 물론이고 국제적으로도 이미 하나의 시대적 추세로, 또 필연적 현상으로 대두돼 있는 상황이다. 그럼 에도 불구하고 국내에서의 물류창고산업에 대한 인식은 매우 저조한 수준이다. 우리나라의 총 물류비는 2004년도 기준 GDP의 11.9%인데 비하여, 미국은 8.4%, 일본은 8.3%이다. 기업 물류비는 2005년도 기준 매출액의 9.7%인데 미국은 7.5%, 일본은 4.8%로 물류비 증가가 우리나라의 기업과 국가경쟁력의 저해 요인이 되고 있다. 따라서 본고에서는 보관물류의 중요한 한 요소인 항만창고를 중심으로 창고경영의 필 요성과 목적, 창고의 종류 그리고 보관물류의 합리적 경영에 관한 실무적 논점을 제시하는데 그 목적이 있다.

Development of Direct Methanol Fuel Cell Systems for Material Handling Applications

Direct methanol fuel cells (DMFCs) are attractive for various applications, above all, however, as replacements for batteries or accumulators. They may be used in different power classes. A market analysis indicated that the use of a DMFC energy system in the kW class had the best chance of commercial realization if applied in forklift trucks for material handling in large distribution centers or warehouses. An advantage of such energy systems is that there is no need for the relatively time-consuming recharging of the lead-acid batteries, nor is it necessary to have spare batteries available for multishift operation. This calls for DMFC energy systems that are capable of replacing the existing Pb accumulators in terms of space requirements and energy. However, this requires considerable improvements to be made in terms of power and stability over time of DMFC systems and, in comparison to their present status, an increase of overall efficiency. Recent cost analyses for the overall system; for example, show that for the DMFC stack, a durability of at least 5000 h must be achieved with an overall efficiency for the DMFC system of at least 30%, with the constraint that the system can be operated in a water-autonomous manner up to an ambient temperature of 35 °C. As part of a joint R&D project with industrial partners, two systems were constructed and each subjected to long-term testing for 3000 and more than 8000 h, respectively, with realistic load profiles from driving cycles. In this test, the stack from the first system, DMFC V 3.3–1, displayed an aging rate of approximately 52 μV h−1 at a current density of 100 mA cm−2. This corresponds to a performance degradation of 25% over a period of 3,000 h. The DMFC V 3.3–2 system, a modified and optimized version of the first system, also underwent long-term testing. In this case, the aging rate of the stack was only approximately 9 μV h−1 at a current density of 100 mA cm−2. The system has thus been operated to date for more than 8000 h under realistic load profiles.

Algorithms for on-line order batching in an order picking warehouse

In manual order picking systems, order pickers walk or ride through a distribution warehouse in order to collect items required by (internal or external) customers. Order batching consists of combining these – indivisible – customer orders into picking orders. With respect to order batching, two problem types can be distinguished: in off-line (static) batching, all customer orders are known in advance; in on-line (dynamic) batching, customer orders become available dynamically over time. This paper considers an on-line order batching problem in which the maximum completion time of the customer orders arriving within a certain time period has to be minimized. The author shows how heuristic approaches for off-line order batching can be modified in order to deal with the on-line situation. In a competitive analysis, lower and upper bounds for the competitive ratios of the proposed algorithms are presented. The proposed algorithms are evaluated in a series of extensive numerical experiments. It is demonstrated that the choice of an appropriate batching method can lead to a substantial reduction of the maximum completion time.

The Dynamic Location Model to Consider Background Traffic

This study concerns to the determination of location of freight distribution warehouses. It is part of a series of research projects on a distribution system we developed to deal with cases in a public service obligation state-owned company (PSO-SOC). This current research is characterized by the consideration of background traffic of the entire time period of planning rather than one certain time target on location model. It is aimed that the location decision to be more applicable and accommodative to the dynamic of the traffic condition. Once the decision is implemented, it will give the best outcome for the entire time period, not only for the initial time, end time or certain time of time period. A heuristic approach is proposed to simplify complexity of the model and network representation technique is applied to solve the model. A hyphotetical example is discussed to illustrate the mechanism of finding the optimal solution in term of both its objective function and applicability.

Recency-based storage assignment and warehouse configuration for recurrent demands

Storage assignment is an important decision problem in warehouse operation management. In conventional problem settings of distribution warehouses, stock items are stored in bulk but retrieved in small quantities. Storage assignment methods typically make use of demand attribute information of order quantity, order frequency and correlation between demands. In this paper, we address a different problem in which the request for the same stock items is stochastically recurrent. The problem arises when the items are needed in production and, after production, are returned to warehouses for later reuse. Examples of such items include tooling in factory, books in library and digital objects in data warehouses. Utilizing the recurrent characteristics, a salient recency-based storage assignment policy and an associated cascaded warehouse configuration are proposed and analyzed in this paper. This paper has four parts. In the first part, a model of recurrent demand is described. In the second part, the efficiency of the recency-based policy and a traditional ID-based policy is analyzed. In the third part, a mathematical programming model for optimal configuration of cascaded warehouses is presented. Finally, a case study of hospital visits is presented. This paper concludes with recommendations on cascading and zoning the warehouse for applying the recency-based policy.

Two-echelon, multi-commodity supply chain network design with mode selection, lead-times and inventory costs

Designing distribution networks – as one of the most important strategic issues in supply chain management – has become the focus of research attention in recent years. This paper deals with a two-echelon supply chain network design problem in deterministic, single-period, multi-commodity contexts. The problem involves both strategic and tactical levels of supply chain planning including locating and sizing manufacturing plants and distribution warehouses, assigning the retailers' demands to the warehouses, and the warehouses to the plants, as well as selecting transportation modes.We have formulated the problem as a mixed integer programming model, which integrates the above mentioned decisions and intends to minimize total costs of the network including transportation, lead-times, and inventory holding costs for products, as well as opening and operating costs for facilities. Moreover, we have developed an efficient Lagrangian based heuristic solution algorithm for solving the real-sized problems in reasonable computational time.

Global Localization and Position Tracking of an Automated Guided Vehicle

AbstractA swarm of Automated Guided Vehicles (AGVs) can be used in warehouses, distribution centers and manufacturing plants in order to automate the internal material flow. This swarm can overcome the disadvantages of roll conveyors and belts. The main problems of AGVs are global localization, position tracking, path planning and communication (especially within the swarm). Another technique which provides potential for logistic applications are Wireless Sensor Networks (WSNs). They can be used in warehouses to realize a decentralized stock database, monitoring a cold chain as well as for localization of an AGV and communication within the swarm. The paper presents a technique for global localization and position tracking of an omnidirectional AGV equipped with Mecanum wheels, which was designed to transport Euro-bins in a distribution center or warehouse. Global localization is realized through a technique based on range measurements obtained from an IEEE 802.15.4a WSN. The WSN is also used for communication within the swarm as well as for communication with the central warehouse computer. A developed sensor fusion of two safety laser range finders with the range measurements of a WSN solve the position tracking task. Laser range finders are used to detect pairs of landmarks to provide accurate positioning for docking maneuvers. The paper also presents a sensor model for IEEE 802.15.4a range measurements and experimental results. The latter show that the global localization technique guarantees accurate positioning and that the sensor fusion can be used for docking applications.

Indoor Energy Analysis of Food Distribution Warehouse

Indoor Energy Analysis of Food Distribution Warehouse