Operations Research, Systems Engineering and Industrial Engineering Commons^™

Exploiting Knowledge About Future Demands For Real-Time Vehicle Dispatching, Soumia Ichoua, Michel Gendreau, Jean Yves Potvin

Soumia Ichoua

An important, but seldom investigated issue in the field of dynamic vehicle routing and dispatching is how to exploit information about future events to improve decision making. In this paper, we address this issue in a real-time setting with a strategy based on probabilistic knowledge about future request arrivals to better manage the fleet of vehicles. More precisely, the new strategy introduces dummy customers (representing forecasted requests) in vehicle routes to provide a good coverage of the territory. This strategy is assessed through computational experiments performed in a simulated environment.

Xiamen Port Bulk Cargo Collection And Distribution Systems Optimization, Juntao Cai

World Maritime University Dissertations

No abstract provided.

Assessing Customer Service In Airports – Models From The Uae, Aman Gupta, Mohammed Arif, Phillip A. Richardson

International Journal of Aviation, Aeronautics, and Aerospace

Customer service at airports has become a key priority for airport operators given the high degree of competitions. This paper uses an airport customer service model to analyze three examples from the United Arab Emirates (UAE). Passenger interviews, statistical information, customer feedback and other forms of information have been utilized to learn more about the customer view on the quality of service offered at these three airports. Detailed qualitative analysis of these case studies has highlighted some key issues in the area of customer service and identifies some opportunities for improvement.

Robust Two-Stage Stochastic Linear Programs With Moment Constraints, Sarah Yini Gao, Lingchen Kong, Jie Sun

Research Collection Lee Kong Chian School Of Business

We consider the two-stage stochastic linear programming model, in which the recourse function is a worst case expected value over a set of probabilistic distributions. These distributions share the same first- and second-order moments. By using duality of semi-infinite programming and assuming knowledge on extreme points of the dual polyhedron of the constraints, we show that a deterministic equivalence of the two-stage problem is a second-order cone optimization problem. Numerical examples are presented to show non-conservativeness and computational advantage of this approach.

Detailed Inventory Record Inaccuracy Analysis, Hayrettin Kaan Okyay

Graduate Theses and Dissertations

This dissertation performs a methodical analysis to understand the behavior of inventory record inaccuracy (IRI) when it is influenced by demand, supply and lead time uncertainty in both online and offline retail environment separately. Additionally, this study identifies the susceptibility of the inventory systems towards IRI due to conventional perfect data visibility assumptions. Two different alternatives for such methods are presented and analyzed; the IRI resistance and the error control methods. The discussed methods effectively countered various aspects of IRI; the IRI resistance method performs better on stock-out and lost sales, whereas error control method keeps lower inventory. Furthermore, this …

Design And Implementation Of Iso:9001 Standards At Sigma 6 Electronics, Inc., Robert Kirkpatrick, Dylan Geisen, Simon Schermerhorn

Industrial Technology and Packaging

ISO 9001 certification is a very long process that can take even the most dedicated team years to complete. For smaller companies such a process could be costly, confusing, and arduous. While many resources exist, it takes nearly the same amount of effort to tailor fit the examples as it does to create a whole new set.

The purpose of this senior project is to research examples and help fit them to a small manufacturing company, Sigma 6 Electronics, Inc. An interlinked, or combined, quality manual/procedures were chosen to aid Sigma 6 Electronics through making the documentation clear and perfectly …

Transport Replacement And Sustainability Aspects Associated With Additive Manufacturing, Marcus R. Wigan

Marcus R Wigan

Additive manufacturing has a range of characteristics that suggest enhancements to sustainability should be possible. The nature of the process influences not only how products can be made, but also how they can be delivered. Logistics and the global supply chain are central aspects to manufacturing, and considerable attention is being paid to making the supply chain more sustainable. This often makes sound economic sense without any consideration of the environmental benefits, as this usually delivers energy reductions and reduced reworking or redelivery. Additive manufacturing has also secured increasing attention from a sustainability standpoint, but this has in the main …

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 …

Comparing Industry And Academic Perspectives On Cross-Docking Operations, Paul Buijs, Iris F.A. Vis

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

This paper performs a comparative analysis on the industry and academic perspectives on cross-docking operations. Detailed descriptions are provided for three typical cross-dock settings by means of case illustrations. The purpose of these descriptions is to inspire break-through innovations in future cross-docking research by identifying constraints, decision problems, and performance indicators that are thoroughly anchored in current practice.

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.

Clickstream Big Data And “Delivery Before Order Making” Mode For Online Retailers, Yeming Yale Gong, Haoxuan Xu

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

Our research is inspired by a leading online retailer using clickstream big data to estimate customer demand and then ship items to customers or hubs near customers by a mode of “delivery before order making” (DBOM) mode. Using clickstream data to obtain advance demand information in order quantities, we integrate the forecasting with a singleitem uncapacitated dynamic lot sizing problem in a rolling-horizon environment. Using the simulated clickstream data, we evaluate the performance of DBOM mode.

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 …

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 …

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 …

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.

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 …

Throughput Analysis Of S/R Shuttle Systems, Georg Kartnig, Jörg Oser

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

Shuttle systems are used in high performance automated storage/retrieval unit load systems. Each storage level is serviced by one transfer car travelling in dual command operation. One buffer slot is located at both ends of each level. This decouples horizontal travel from vertical input/output moves, which in this case requires two independent vertical reciprocating lifts at each end of the aisle. Other systems work with only one lift used in lower throughput applications. The content of this paper is treated in the following sections starting with a problem definition and a literature survey. This is followed by a detailed functional …

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. …

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 …

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 …

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.

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 …

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. …

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 …

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 …

Integrating Analysis Into A Warehouse Design Workflow, Leon Mcginnis, Timothy Sprock

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

Supply chain analyses, including those related to material handling systems, are typically purpose-built to answer specific questions and therefore have many different implementations depending on the question, the instance data, and the solver. The purpose-built nature of these models makes it difficult to integrate them into an iterative design workflow. Despite the myriad analysis implementations, the fundamental structure of these systems and their problem domain remains unchanged, suggesting that perhaps analyses could be automatically generated on demand, given an appropriate specification of the particular system to be analyzed. We apply model-based systems engineering (MBSE) methodologies to explore this possibility in …

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 …

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.