Open Access. Powered by Scholars. Published by Universities.®

Operations Research, Systems Engineering and Industrial Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 151 - 174 of 174

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

The Future Of Modeling In Material Handling Systems, Leon F. Mcginnis Sep 2010

The Future Of Modeling In Material Handling Systems, Leon F. Mcginnis

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Today, when we talk about “modeling” in the context of material handling systems, invariably we are referring to a mathematical or computational model for analyzing some aspect of the system, such as its throughput rate, response time, cost of ownership, required storage capacity, etc. Creating these kinds of models requires considerable knowledge in at least two domains the material handling system domain, and the analysis methodology domain—and considerable skill in the “art of modeling” in order to express the former in the terms of the latter. The results can be somewhat ad hoc—e.g., two different modelers are likely to create …


Optimizing Distribution Center Configuration: A Practical View Of A Multi-Objective Problem, Russell D. Meller, Lisa M. Thomas Sep 2010

Optimizing Distribution Center Configuration: A Practical View Of A Multi-Objective Problem, Russell D. Meller, Lisa M. Thomas

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

The shape of a distribution center, as well as whether dock locations are on one side or two sides of the facility, impacts measures like travel distances and the number of dock locations that may be utilized. Thus, for a required number of pallet locations, there are multiple combinations of distribution center shape and dock configurations that should be evaluated against multiple measures. We have developed a practical model for making such evaluations and illustrate the model with data reflective of a partner in the Center for Engineering Logistics and Distribution.


A Flowshop Scheduling Problem With Transportation Times And Capacity Constraints, Abraham Mendoza, Jose A. Ventura, Kwei Long Huang Sep 2010

A Flowshop Scheduling Problem With Transportation Times And Capacity Constraints, Abraham Mendoza, Jose A. Ventura, Kwei Long Huang

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Although there are numerous methodologies and research studies on machine scheduling, most of the literature assumes that there is an unlimited number of transporters to deliver jobs from one machine to another for further processing and that transportation times can be neglected. These two assumptions are not applicable if one intends to generate an accurate schedule for the shop floor. In this research, a flowshop scheduling problem with two machines, denoted as M1 and M2, and a single transporter with capacity c is considered. The main focus is on the development of a dynamic programming algorithm to generate a schedule …


Using Data Envelopment Analysis To Evaluate The Performance Of Third Party Distribution Centers, Ching-Jung Ting, Hsueh-Lin Fang Sep 2010

Using Data Envelopment Analysis To Evaluate The Performance Of Third Party Distribution Centers, Ching-Jung Ting, Hsueh-Lin Fang

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

There has been considerable interest worldwide in last few years in the growth of third party logistics (3PL) providers. 3PL distribution center (DC) enables firms to achieve reduced operating costs, increased revenues, and to focus on their core competence. This research aims to find the key performance indicators through a survey of a set of DCs and then evaluate their efficiency over the period 2005-2007 using data envelopment analysis (DEA) models based on selected performance indicators as inputs and outputs. Three inputs and two outputs for all DCs from the surveyed performance indicators were selected in this study. DEA is …


Class-Based Storage With A Finite Number Of Items, Yugang Yu, René B.M. De Koster Sep 2010

Class-Based Storage With A Finite Number Of Items, Yugang Yu, René B.M. De Koster

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

ABC class-based storage is widely studied in literature and applied practice. It divides all stored items into a limited number of classes according to their demand rates (turnover per unit time). Classes of items with higher turnovers are stored in a region closer to the warehouse depot. In literature, it is commonly shown that the use of more storage classes leads to shorter travel time for storing and retrieving items. A basic assumption in this literature commonly is that the required storage space of items equals their average inventory levels, which is right if an infinite number of items are …


Determination Of Operational Parameters For An Efficient Container Service In The Port Of Guaymas, Cesar Meneses, J. René Villalobos Sep 2010

Determination Of Operational Parameters For An Efficient Container Service In The Port Of Guaymas, Cesar Meneses, J. René Villalobos

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

The port of Guaymas is located in Sea of Cortez in the Northern Pacific Coast of Mexico. Its hinterland is basically the Northwestern region of Mexico and the Southwestern United States. The Port currently focuses on bulk and liquid cargo and does not provide container services. In this paper, we explore some of the characteristics that a container service should have to be competitive in servicing the needs of the regional industry. Since the study deals with port selection decision from the industry’s point of view, we introduce a port selection model based on a Total Landed Cost (TLC) metric. …


Empirically-Based Warehouse Design: Can Academics Accept Such An Approach?, James M. Apple Jr., Russell D. Meller, John A. White Jr. Sep 2010

Empirically-Based Warehouse Design: Can Academics Accept Such An Approach?, James M. Apple Jr., Russell D. Meller, John A. White Jr.

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

It is our opinion that existing research is not sufficient to support the design of a warehouse. As a result, facility designers that work in practice are left to face the design process with their own methods. These methods are in stark contrast to the analytical models developed in academia in that they are highly based on empirical observations. Supported by a collection of empirical observations, facility designers who work in practice employ an ad hoc design process. We present a design process based on empirical observations and then formalize it so that it can be taught and used. We …


Design Of Warehouse For Material, Which Is Non-Uniform And Difficult To Handle, Andrea Seidlova, David Sourek Sep 2010

Design Of Warehouse For Material, Which Is Non-Uniform And Difficult To Handle, Andrea Seidlova, David Sourek

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Main goal of this paper is warehouse layout optimization with emphasis on maximum space utilization. It is about rack system design, which leads to capacity maximization of warehouse for non-uniform material with heavy weight. The warehouse system has to enable at least partial automation (the possibility to use AS/RS system), minimization of service time and minimization of man effort. Initial constraining conditions for warehouse design in our case are warehouse area, maximum load of racks or shelves, maximum allowed floor load and existing location of arrival road for material loading and unloading.


Monitoring Inventory Accuracy With Statistical Process Control, Kyle Huschka, John R. English, Todd Easton, Andrew Huschka Sep 2010

Monitoring Inventory Accuracy With Statistical Process Control, Kyle Huschka, John R. English, Todd Easton, Andrew Huschka

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Inventory accuracy is critical in most industrial environments such as distribution, warehousing, and retail. Many companies use a technique called cycle counting and have realized outstanding results in monitoring and improving inventory accuracy. The time and resources to complete cycle counting are sometimes limited or not available. In this work, we promote statistical process control (SPC) to monitor inventory accuracy. Specifically, we model the complex underlying environments with mixture distributions to demonstrate sampling from a mixed but stationary process. For our particular application, we concern ourselves with data that result from inventory adjustments at the stock keeping unit (SKU) level …


Freight Sequencing To Improve Hub Operations In The Less-Than-Truckload Freight Transportation Industry, Xiangshang Tong, Kimberly Ellis, Amy Brown Greer Sep 2010

Freight Sequencing To Improve Hub Operations In The Less-Than-Truckload Freight Transportation Industry, Xiangshang Tong, Kimberly Ellis, Amy Brown Greer

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

In less-than-truckload freight transportation, hub operations affect the service levels that carriers are able to provide their customers. This paper focuses on improving the efficiency of hub operations by reducing freight handling time and cost. Specifically, the freight sequencing problem (FSP) is investigated to determine the freight unloading and loading sequence that minimizes the time for dock workers to transfer shipments from origin trailers to destination trailers. The FSP is modeled as a Rural Postman Problem (RPP) and three algorithms are compared: trailer-at-atime, nearest neighbor, and balance-and-connect. Using five industrial data sets, the results demonstrate the effectiveness, advantages, and disadvantages …


Distribution Planning Considering Warehousing Decisions, Pratik J. Parikh, Xinhui Zhang, Bhanuteja Sainathuni Sep 2010

Distribution Planning Considering Warehousing Decisions, Pratik J. Parikh, Xinhui Zhang, Bhanuteja Sainathuni

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Modern supply chains heavily depend on warehouses for rapidly fulfilling customer demands through retail, web-based, and catalogue channels. The traditional approach that considers warehouses as cost-centers has affected the profitability of numerous supply chains. A lack of synchronization between procurement and allocation decisions causes warehouses to scramble for resources during peak times and be faced with under-utilized resources during drought times. Warehouses, however, have emerged as service-centers and it is imperative that warehousing decisions be an integral part of supply chain decisions. In this paper we propose a mixed-integer programming model to integrate warehousing decisions with those of inventory and …


Blocking Effects On Performance Of Warehouse Systems With Automonous Vehicles, Ananth Krishnamurthy, Sunderesh Heragu, Charles Malmborg Sep 2010

Blocking Effects On Performance Of Warehouse Systems With Automonous Vehicles, Ananth Krishnamurthy, Sunderesh Heragu, Charles Malmborg

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Distribution centers are under increasing pressure to adopt material handling systems that offer greater flexibility to improve cycle time and throughput capacity in the transfer of unit loads in their high density storage areas. Autonomous Vehicles-based Storage and Retrieval Systems (AVS/RS), have been shown to hold significant promise in this context. In these systems, loads are transferred by autonomous vehicles. Vehicles support horizontal load movement along aisles and cross-aisles within a tier, and lifts support vertical movement between tiers. Existing research in AVS/RS, do not explicitly account for the potential blocking of vehicles and lifts while they are processing transactions. …


Designing Automated Warehouses By Minimising Investment Cost Using Genetic Algorithms, Tone Lerher, Iztok Potrc, Matjaz Sraml Sep 2010

Designing Automated Warehouses By Minimising Investment Cost Using Genetic Algorithms, Tone Lerher, Iztok Potrc, Matjaz Sraml

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

The successful performance of the automated storage and retrieval systems is dependent upon the appropriate design and optimization process. In the present work a comprehensive model of designing automated storage and retrieval system for the single- and multi-aisle systems is presented. Because of the required conditions that the automated storage and retrieval systems should be technically highly efficient and that it should be designed on reasonable expenses, the objective function represents minimum total cost. The objective function combines elements of layout, time-dependent part, the initial investment and the operational costs. Due to the nonlinear, multi-variable and discrete shape of the …


Towards A Physical Internet: The Impact On Logistics Facilities And Material Handling Systems Design And Innovation, Benoit Montreuil, Russell D. Meller, Eric Ballot Sep 2010

Towards A Physical Internet: The Impact On Logistics Facilities And Material Handling Systems Design And Innovation, Benoit Montreuil, Russell D. Meller, Eric Ballot

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Aiming for a radical sustainability improvement, the Physical Internet has the potential of revolutionizing the fields of material handling, logistics, transportation and facilities design. It exploits the enabling concept of standardized, modular and smart containers as well as the universal interconnectivity of logistics networks and services. Its underlying paradigm shift creates a tremendous breakthrough innovation opportunity for the material handling and facility logistics community in terms of equipment, systems and facility design and operation. This paper provides a primer overview of a key subset of the physical elements serving as the foundation of the Physical Internet infrastructure, classified in three …


Plug-And-Work Material Handling Systems, Kai Furmans, Frank Schonung, Kevin R. Gue Jan 2010

Plug-And-Work Material Handling Systems, Kai Furmans, Frank Schonung, Kevin R. Gue

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

One disadvantage of automated material handling systems is their relative Inflexibility: once racks are installed and conveyors are laid, making even mi-nor changes to a system can be cumbersome and expensive. However, recent progress in the capabilities and cost of basic system components, such as controllers, drives, and sensors, has made possible a new class of material handling systems having a much higher degree of flexibility. We propose underlying de- sign principles for such systems and describe several prototype plug-and-work" systems, which feature decentralized control and ease of reconfiguration.


Optimizing The Rearrangement Process In A Dedicated Warehouse, Hector J. Carlo, German E. Giraldo Jan 2010

Optimizing The Rearrangement Process In A Dedicated Warehouse, Hector J. Carlo, German E. Giraldo

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Determining the optimal storage assignment for products in a dedicated warehouse has been addressed extensively in the Facility Logistics literature. However, the process of implementing a particular storage assignment given the current location of products has not received much attention in the existing literature. Typically, warehouses use downtime or overtime to remove products from their current location and move them to the suggested location. This work presents the Rearrange-While-Working (RWW) policy to optimize the process of rearranging a dedicated warehouse. The RWW policy seeks to relocate products in a warehouse from the initial arrangement to the optimal arrangement while serving …


A New Milp Approach For The Facility Layout Design Problem With Rectangular And L/T Shaped Departments, Yossi Bukchin, Michal Tzur Jan 2010

A New Milp Approach For The Facility Layout Design Problem With Rectangular And L/T Shaped Departments, Yossi Bukchin, Michal Tzur

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

In this paper we propose a new approach for the facility layout problem (FLP) and suggest new mixed-integer linear programming (MILP) formulations. The proposed approach considers simultaneously the location of the departments within the facility and the internal arrangement of the machines. Two models are suggested, where the first addresses the rectangular department case and the second allows nonrectangular departments defined by an L/T shape. New regularity constraints are developed to avoid irregular department shapes.


The Human-Centric Warehouse, Kevin R. Gue Jan 2010

The Human-Centric Warehouse, Kevin R. Gue

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

In theory and in practice, the objective of warehouse design has long been to meet operational requirements of throughput and service performance at minimum cost. A natural product of this “bottom line” approach has been warehouse buildings and operations ill-suited to the humans who spend their working lives interacting with them. We offer an explanation for the current approach, and argue that a new approach— a new paradigm —is needed. We then describe a comprehensive approach to warehouse design that includes human well-being as a primary goal.


Accidents Will Happen. Do Safety Systems Improve Warehouse Safety Performance?, Rene B. M. De Koster, B. M. Balk, I Davelaar, M. Martens Jan 2010

Accidents Will Happen. Do Safety Systems Improve Warehouse Safety Performance?, Rene B. M. De Koster, B. M. Balk, I Davelaar, M. Martens

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Safety is becoming more and more an issue in warehouses. In the literature, effective measures leading to increased occupational health and safety have hardly been researched. Most research focuses on the impact of perceived safety-related leadership of managers and worker safety consciousness on ‘safety climate’ and workers’ safe behavior. We have carried out exploratory research into which measures really improve the safety performance of a warehouse. We particularly focus on the effects of (1) safety-related work procedures, (2) safety leadership, and (3) workers’ safety consciousness. Based on a survey we show that safety leadership and safety-related work procedures significantly drive …


Forklift Routing In Warehouses Using Dual-Commands And Stackable Pallets, Ahmed Hassan, Bill Ferrell Jan 2010

Forklift Routing In Warehouses Using Dual-Commands And Stackable Pallets, Ahmed Hassan, Bill Ferrell

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

This research determines time optimal routes for loading and picking pallets that can be stacked on top of each other during transport in a manual warehouse that only contains full pallets and utilizes single deep storage. This research was motivated by the fact that we are seeing this situation on an ever increasing basis, particularly in warehouses that supply parts to automotive assembly. In practice, forklift drivers have developed strategies to take advantage of this opportunity but to our knowledge there is no literature that addresses this problem rigorously. The important features of this work are that a time based …


Evaluating The Effect Of Operational Conditions And Practices On Warehouse Performance, Andrew L. Johnson Jan 2010

Evaluating The Effect Of Operational Conditions And Practices On Warehouse Performance, Andrew L. Johnson

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Analyzing warehouse performance across different environments is critical to improving overall productivity and reducing costs. Although two-stage DEA estimators have been shown to be statistically consistent, the finite sample bias of DEA in the first stage carries over to the secondstage regression, which causes bias in the estimated coefficients of the contextual variables. The bias is particularly severe when the contextual variables are correlated with inputs. To address this shortcoming, we apply insights from Johnson and Kuosmanen (2010), who demonstrate that DEA can be formulated as a constrained special case of the Convex Nonparametric Least Squares (CNLS) regression to develop …


Strategic Design Of A Robust Supply Chain, Marc Goetschalckx, Edward Huang Jan 2010

Strategic Design Of A Robust Supply Chain, Marc Goetschalckx, Edward Huang

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

The strategic design of a robust supply chain has as goal the configuration of the supply chain structure so that the performance of the supply chain remains of a consistently high quality for all possible future scenarios. We model this goal with an objective function that trades off the central tendency of the supply chain profit with the dispersion of the profit as measured by the standard deviation for any value of the weights assigned to the two components. However, the standard deviation, used as the dispersion penalty for profit maximization, has a square root expression which makes standard maximization …


Control Policies For A Dynamic Storage System With Multiple Lifts And Shuttles, Iris F.A. Vis, Hector J. Carlo, Paloma Diaz, Maria E. Laboy, Bruno Vanwijgaarden Jan 2010

Control Policies For A Dynamic Storage System With Multiple Lifts And Shuttles, Iris F.A. Vis, Hector J. Carlo, Paloma Diaz, Maria E. Laboy, Bruno Vanwijgaarden

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

New types of Automated Storage and Retrieval Systems, able to achieve high throughput levels, are continuously being developed and require new control polices to take full advantage of the developed system. In this paper we study a dynamic storage system as developed by Vanderlande Industries consisting of a conveyor, two lifts, multiple transfer shuttles, and a storage rack. One of the decision problems for this system is the scheduling problem of the two lifts. In other words, which lift is going to handle which request and in which order. In this paper, we derive an integrated look-ahead heuristic based on …


Comparing Transport Policies In A Full-Scale 300mm Wafer Manufacturing Facility, J. E. Kiba, S. Dauz`Ere-P´Er`Es, C. Yugma, G. Lamiable Jan 2010

Comparing Transport Policies In A Full-Scale 300mm Wafer Manufacturing Facility, J. E. Kiba, S. Dauz`Ere-P´Er`Es, C. Yugma, G. Lamiable

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Research in semiconductor manufacturing ideally wants to determine the “best” transport policy to ensure continuous production. Determining such a policy is difficult because it depends on many factors such as the layout, the product types, the equipment, etc. Most of the transport policies found in the literature combine dispatching policies (scheduling of transport requests) and routing policies (selection of the path to move from one point to another). This paper investigates a policy called "minimum service" which consists in keeping a minimum number of available vehicles in bays, so that they can quickly answer transport requests and empty travel times …