Operations Research, Systems Engineering and Industrial Engineering Commons^™

Comparison Of Alternative Configurations For Dense Warehousing Systems, Kevin R. Gue, G. Don Taylor

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

In heavily constrained environments requiring very high density storage, traditional aisle-based warehousing may not provide viable options. One feasible manifestation of high density storage systems is the ‘puzzle-based’ system, in which unit loads are moved through the system via manipulation of empty (escort) locations to retrieve desired items. Another option would be the use of movable concentric rings, with escorts being utilized to enable lateral movements of unit loads between the rings. In this paper, the authors present analytical results to compare retrieval time performance for these two types of high density storage systems for randomly demanded items under various …

Analysis Of Class-Based Storage Strategies For The Mobile Shelf-Based Order Pick System, Shobhit Nigam, Debjit Roy, Rene De Koster, Ivo J.B.F. Adan

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Mobile Shelf-based Order Pick (MSOP) systems are gaining significant in- terest for e-commerce fulfillment due to their rapid deployment capability and dynamic organization of storage pods based on item demand profiles. In this research, we model the MSOP system with class-based storage strategies and alternate pod storage policies using multi-class closed queuing networks. We observe that though closest-open location pod storage policy do not allow to efficiently use the storage spaces in comparison to random location pod storage policy in an aisle, it increases the system throughput for all item classes.

A Two-Level Stochastic Model To Estimate Vessel Throughput Time, Debjit Roy, Vibhuti Dhingra, Rene De Koster

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

A good estimate of the vessel sojourn time is essential for better planning and scheduling Of container terminal resources,such as berth scheduling,quay crane(qc)assignment And scheduling,and fleet size planning. However,estimating the expected vessel so journ Time is a complex exercise because the time is dependent on several terminal operating Parameters such as the size of the vessel,the number of containers to be loaded and Unloaded,and the through put of the qcs. The through put of the qcs in turn depends On the type and number of transport vehicles,number of stack blocks,the topology of The vehicle travel path,the layout of the terminal,and …

An Empirical Study About The Effectiveness Of Lean Empowerment In Warehouses, Kai Furmans, Payam Dehdari

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Lean Management is well established in production environments. Some empirical evidences are available which suggest that in production systems lean management achieves positive results. For warehousing, some works have already been done, which deal with the application and adaption of lean tools for usage in warehousing. In order to answer the question, whether the application of lean tools leads to a better performance however, no study is available today. Therefore, an empirical study has been conducted, where the effectiveness of lean empowerment has been tested and compared to the performance of warehouse, who continued to work as before.

Performance Comparison Of Various Order Picking Methods In Different Behavioral Contexts, Jelle De Vries, Rene De Koster, Daan Stam

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Three manual picker-to-parts order picking methods (parallel picking, zone picking, and dynamic zone picking) are employed in an experimental warehouse setup and compared in terms of productivity, quality, and job satisfaction. Participants worked in teams and were subject to either an individual- based, or a team-based incentive scheme. Furthermore, the influence of individual participants’ dominant regulatory focus (promotion or prevention) was taken into account. The outcomes show that in parallel picking an incentive system focused on individual performance is beneficial for productivity and quality compared to an incentive system focused on team performance, whereas team-based incentives are more productive in …

A Framework For The Robust Design Of Unit Load Storage Systems, Marc Goetschalckx, Edward Huang, Pratik Mital

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

The unit load storage assignment problem determines the assignment of a set of unit loads with known arrival and departure times to a set of unit storage locations in a warehouse. The material handling device(s) can carry at most one unit load at the time. In this research it is assumed that each of the storage locations can be accessed directly without load relocations or rearrangements and that the travel times between the storage locations and from and to the warehousing docks can be computed in advance. The objective is to minimize the total travel time of the material handling …

Modeling Conveyor Merges In Zone Picking Systems, Rene De Koster, Ivo J.B.F. Adan, Jacques Resing

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

In many order picking and sorting systems conveyors are used to transport products through the system and to merge multiple flows of products into one single flow. In practice, conveyor merges are potential points of congestion, and consequently can lead to a reduced throughput. In this paper, we study merges in a zone picking system. The performance of a zone picking system is, for a large part, determined by the performance of the merge locations. We model the system as a closed queueing network that describes the conveyor, the pick zones, and the merge locations. The resulting model does not …

A New Approach For Generating Facility Layouts Using An Algorithmic Approach, Volker Sadowsky, Christian Mosblech

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

In this paper a new approach is described to automatically create layouts for material flow systems. The current research in progress aiming at adopting the methods and algorithms of the Electronic Design Automation to be used in logistics planning is presented. These methods are already applied to create microchips being multiple times more complex than material flow systems while following the same goal: Functional units have to be placed on a predefined area and are linked by connections weighted differently. This basic requirement can be applied to microchip designs as well as material flow systems. The common condition is to …

Setting Cutoff Times For Picking Systems With Capacity Degradation, Kevin R. Gue

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

In the new landscape of e-commerce distribution, firms must offer increasingly aggressive delivery promises and then make good on them. These promises often take the form of a cutoff time, such that orders placed before the cutoff time receive premium service (next-day, same-day, etc.) and those placed afterward do not. Later cutoff times are stronger, of course, but the fulfillment system might not be able to process the order before the deadline. How late is too late? We develop a deterministic model to answer this and related questions when the order fulfillment system batches orders for efficient picking operations and …

Robust Truckload Relay Network Design Under Demand Uncertainty, Hector A. Vergara, Zahra Mokhtari

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

This research addresses the issue of incorporating demand uncertainty in the strategic design of relay networks for truckload transportation. An existing composite variable mathematical model for the design of hybrid relay networks is extended by developing its robust counterpart. The proposed approach considers uncertainty in the number of truckloads to be dispatched between a pair of nodes in the network which is characterized by a symmetric interval around the expected demand value. A two-step heuristic approach is used to solve the robust model. Several numerical experiments are carried out to study the differences between the solutions obtained with the robust …

Experimental Validation Of Travel Time Models For Shuttle-Based Automated Storage And Retrieval System, Zaki Sari, Latefa Ghomri, Banu Y. Ekren, Tone Lerher

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

In this paper, we aim to validate travel time models for single and dual command cycle displacements of lifts and shuttles in a shuttle-based automated storage and retrieval system (SBS/RS) by using experimental computer simulation. The models under consideration take into account acceleration and deceleration delays. We use ARENA 12 software for the simulation modeling. By simulation, we emulate the real functioning of the system. Therefore, we assume that the results from the ARENA simulation are equivalent to the onsite experimentation. Simulation results are very close to those obtained by analytical travel time models. This shows the high precision of …

Model And Algorithm For Supply Chain Analysis In Energy-Wood Industry, Thorsten Schmidt, Hannes Hahne

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Short rotation coppices are a renewable energy concept based on renewable raw material. This paper proposes a model and calculation method which generates valid supply chains using quantified technological and infrastructural constraints.

Integrate Vehicle Routing And Truck Sequencing In Cross-Docking Operations, Ching-Jung Ting, Ting-Don Chen

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Cross-docking is a an important logistics strategy in which freight is unloaded from inbound vehicles and directly loaded into outbound vehicles, with little or no storage in between. This study considers a crossdocking system which combines the vehicle routing problem with crossdocking (VRPCD) for both inbound and outbound operations and truck sequencing problem at docks. The objective is to minimize the logistics center operation costs and transportation costs. We first formulated the integrated problem with a mixed integer programming model. Since VRPCD and sequencing problems are NP-hard, the integrated problem is also an NP-hard problem. We propose an ant colony …

The Cube Per Order Index Slotting Strategy, How Bad Can It Be?, Peter C. Schuur

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

A well-known and frequently applied policy to assign stock keeping units (SKUs) to (dedicated) storage locations in a warehouse is the Cube per Order Index (COI) slotting strategy. Basically, COI stores an SKU based on how frequently it is picked per unit of stock space required. Fast movers are located close to the Input-Output points. For single command order picking, COI slotting is well-known to minimize order picking travel time. For multi command this is no longer true. An interesting question is: how bad can it be? In this paper we show that there is no limit to this badness. …

Development Of A Heuristics For A Criteria Based Planning Of Pallet Storage Systems, Detlef Spee, Michael Schmidt, Steffen Schieweck

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Reproducible and quantitative reasoning as the foundation for high-quality planning processes evolves to be key to achieve high quality of speed for logistical processes. This article strives to fulfill this demand by developing a coherent heuristics for the planning of pallet storage systems. The heuristics uses quantitative approaches provided by the available literature. In case of nonexistent sources, the missing components are developed and integrated. To be applicable in an industrial environment, the comparison and assessment of the created implementation alternatives is mainly monetary based. The heuristics follows a modular structure to achieve adaptability and extensibility. It explicitly does not …

Data Model And Software Tools For Modeling Picking Operations, Jeffrey S. Smith

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Presenter will provide.

An Analysis Of Single-Command Operations In A Mobile Rack (As/Rs) Served By A Single Order Picker, Amine Hakim Guezzen, Zaki Sari

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

A Mobile rack Automated Storage and Retrieval Systems (MAS/ RS) are picker-to-stock retrieval model which are a variation of the multi aisles AS/RS. This mobile storage system is composed of racks moving laterally on rails so that one can open an aisle between any two adjacent racks, the input/output system, the storage and retrieval (S/R) machine and the computer management system or the control system. Evaluating an AS/RS could be done using several performance indicators, the two most important ones are: The utilization rate of the S/R machine and the average time necessary to serve storage or retrieval requests (the …

Order Batching With Time Constraints In A Parallel-Aisle Warehouse: A Multiple-Policy Approach, Soondo Hong, Andrew L. Johnson, Brett A. Peters

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

A commitment of delivery time is critical in some online businesses (De Koster, 2003). An important challenge to meeting customers’ needs is timely order picking which is also relevant to worker safety, item freshness, overall operational synchronization, and reduced overtime. We analyze an order batch picking situation where a trip is constrained by vehicle capacity and must be completed within a specified time. We develop a model which partitions orders to batches to minimize the total travel time such that each trip meets the orders’ time constraints and capacity limit, and also determines a suitable operational policy for each batch. …

Designing Retail Facilities To Improve Product Exposure, Pratik J. Parikh, Corinne Mowrey

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

A retail facility should effectively engage consumers during their shopping trips if they want to convert demand into purchases. Unfortunately, the complexity of the retailing environment and lack of scientific tools often results in gut-feel approaches experimented in practice. A key factor to retail design often alluded to, but rarely analyzed, is product exposure to the travelling shopper. We define the extent of the shopper's field of vision in order to determine the actual exposure of products experienced by a traveling shopper. In so doing, we can explore the effect rack orientation has on product exposure. Our main contributions include …

Modular Design Of Physical Internet Transport, Handling And Packaging Containers, Benoit Montreuil, Eric Ballot, William Tremblay

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

This paper proposes a three‐tier characterization of Physical Internet containers into transport, handling and packaging containers. It first provides an overview of goods encapsulation in the Physical Internet and of the generic characteristics of Physical Internet containers. Then it proceeds with an analysis of the current goods encapsulation practices. This leads to the introduction of the three tiers, with explicit description and analysis of containers of each tier. The paper provides a synthesis of the proposed transformation of goods encapsulation and highlights key research and innovation opportunities and challenges for both industry and academia.

An Experimental Study Of The Impact Of Warehouse Parameters On The Design Of A Case-Picking Warehouse, Russell D. Meller, Lisa M. Thomas

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

The best design for a warehouse is based on its ability to meet the demands placed on the warehouse, which are typically characterized by warehouse parameters like the order , inventory requirements, etc. Consequently, these parameters should be considered in the design process. In this paper we characterize the design of a case-picking ware- house with design variables and identify the warehouse parameters that have the greatest impact in setting the values of these variables. With our analysis, the search for the optimal design can be reduced by limiting the design space considered.

A Frame Work And Analysis To Inform The Selection Of Piece-Level Order-Fulfillment Technologies, Jennifer A. Pazour, Russell D. Meller

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Thepiece-levelorder-fulfillmenttechnologyselectionproblemisanimportantstrategicproblemthatsignificantlyimpactsdistributioncentercosts andoperations,andistypicallysolvedbasedonempiricalexperiences.Given ademandcurveandasuiteofavailablepiece-levelorder-fulfillmenttechnologies, weanalyzewhereinthedemandcurvedifferentorder-fulfillment technologiesshouldbeapplied. Todoso, wedevelopaframeworkthat jointlydeterminesthebestcombinationofpiece-levelorder-fulfillmenttechnologiesandtheassignmentofSKUstothesetechnologies, whichrelaxes thesequential-modelingapproachofpreviousresearch. Wevalidateour methodologywithindustrydataandshowthatour modelprovidestechnologyrecommendationsandSKUassignmentsthatareconsistent with successfulimplementations. Throughasetofnumericalexperimentsand statisticalanalysis,weidentifykeyfactorsinimplementingmanualversus automatedorder-fulfillmenttechnologiesandprovideobservationsintothe applicationofdifferentorder-fulfillmenttechnologystrategies.Finally,we presentconclusionsandfutureresearchdirections.

Optimization Of Skus' Locations In Warehouse, David Sourek, Vaclav Cempirek

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Many companies, which deal with warehousing, optimize their warehouses. The main business of these companies is to offer to customers the warehousing services. It is possible to note that these companies are specialized in warehousing. On the other hand, we can find companies, which have as the main business the selling of goods to customers. These companies use the warehouses too but in a little bit different way. The arrangement of their warehouses can be very unsuitable and convenient for optimization. Our paper is focused on optimization of stored goods’ locations based on market basket analysis. The solution of this …

Grid Facilities Design: Dynamic Modular Deployment Of Production, Handling And Storage Resources, Suzanne Marcotte, Benoit Montreuil

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

To survive and thrive in a fast-moving environment, facilities must be designed to show adaptability, flexibility and robustness. As some facilities are depicted by heavy and sophisticated equipment costly and hard to displace, others are composed of moveable workstations with highly flexible workers. In most cases, the trade-off is between the cost of redeploying the resources and the excessive cost of material handling and storage incurred by an inefficient deployment of the resources. We propose a design strategy based on (1) conceiving and designing the facility as a stable grid of modules, (2) dynamically deploying production, storage and handling resources …

Modeling And Optimization Of Radio Frequency Identification Networks For Inventory Management, Atipong Suriya, Jose D. Porter

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Stock loss and out-of-stocks are outcomes of poorly designed inventory management systems and can lead to significant revenue losses. Inventory management systems (IMSs) based on radio frequency identification (RFID) have the potential to minimize these losses if they are properly designed and deployed. However, the placement of RFID readers to support IMSs is often done on a trial and error basis which is time consuming and results in less than optimal coverage. A methodology to find the optimal location and number of RFID readers in a warehouse facility to ensure a desired level of radio frequency signal coverage was developed …

Real-Time Dock Door Monitoring System Using A Kinect Sensor, Hector J. Carlo, Cristina Pomales- Garcia, Yeiram Martinez

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

This study presents a proof of concept where a single Microsoft Kinect sensor is used for automated monitoring of a dock door in real-time. The proposed system will automatically and in real-time: (1) detect when an object breaches the dock door perimeter, and its corresponding speed and direction, (2) count the number of pallets loaded/unloaded to/from a trailer, (3) record the loading/unloading time of each load, and (4) reconstruct an image of every loading/unloading trip at a dock door, irrespectively of the material handling travel speed and direction. Particular emphasis is given to discussing how to extend the proposed concept …

Global E-Mentoring: Overcoming Virtual Distance For An Effective Mentoring Relationship, Nancy Philippart

Wayne State University Dissertations

Mentoring can enhance an employee's career development and advancement but traditional face-to-face mentoring has become less relevant because of globalization, increased employee mobility and technology-enabled work. A new mentoring model enabled by technology has emerged to meet the needs of today's complex, fast changing global workplace. Although e-mentoring has several advantages over traditional mentoring, the absence of regular face-to-face interactions requires different strategies to develop an effective mentoring relationship. Moreover, additional complexities arise when this virtual mentoring is global.

This research utilizes the construct of virtual distance, the "psychological separation" that has been found to impact performance outcomes of geographically …

Xqx Based Modeling For General Integer Programming Problems, Vijay P. Ramalingam

Electronic Theses and Dissertations

We present a new way to model general integer programming (IP) problems with in- equality and equality constraints using XQX. We begin with the definition of IP problems folloby their practical applications, and then present the existing XQX based models to handle such problems. We then present our XQX model for general IP problems (including binary IP) with equality and inequality constraints, and also show how this model can be applied to problems with just inequality constraints. We then present the local optima based solution procedure for our XQX model. We also present new theorems and their proofs for our …

A Decision Modeling For Phasor Measurement Unit Location Selection In Smart Grid Systems, Seung Yup Lee

Wayne State University Theses

As a key technology for enhancing the smart grid system, Phasor Measurement Unit (PMU) provides synchronized phasor measurements of voltages and currents of wide-area electric power grid. With various benefits from its application, one of the critical issues in utilizing PMUs is the optimal site selection of units.

The main aim of this research is to develop a decision support system, which can be used in resource allocation task for smart grid system analysis. As an effort to suggest a robust decision model and standardize the decision modeling process, a harmonized modeling framework, which considers operational circumstances of component, is …

A Production Planning System For A Lubricating Oil Production Company, Panisorn Saerevatanawoot

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this research is to develop a production planning system for a lubricating oil company. The company is facing a problem of excessive inventory of finished goods and packaging materials resulting from the minimum stock levels that were established by its customer. The scope of the system covers class A products, consisting of 14 of 45 products in the company, and their packaging materials. The causes of the inventory problem were brainstormed with the use of Cause-and-Effect Diagram, then the Cause-and-Effect Matrix was used to identify potential root causes. It was concluded that master production schedule (MPS) of …