Operations Research, Systems Engineering and Industrial Engineering Commons^™

Optimizing Student Workforce Scheduling At Psu Office Of Information Technology (Oit), Agam Ebramsyah, Aishwarya Joy, Cody Miller, Jake Stevens, Priyanka Patil

Engineering and Technology Management Student Projects

A significant challenge for businesses of any size, is generating a work schedule that ensures adequate personnel coverage to ensure all aspects of the business are properly staffed, while preventing waste produced from having an excess number of employees working at a given time. The decision to manually create spreadsheets and work schedules that take into account availability, staffing requirements, and cost efficiency can become overwhelming and labor intensive. For Portland State University's Office of Information Technology (OIT), there is a significant challenge in scheduling student workers, while ensuring staffing requirements are met, student work hour restrictions are observed, and …

Organics To You - Optimization Of Produce Bins, Rassaniya Lerdphayakkarat, Chuan Chieh Lu, Jon Roschke, Juliana Suzuki, Jessie Truong

Engineering and Technology Management Student Projects

Organics to You (www.organicstoyou.org ) is a produce delivery company that focuses on bringing organic local food from local farms straight to the homes, schools, and businesses of its clients. Each week a "Small Bin" is created using different varieties of local produce from various farms. Customers receive a bin that contains 12-14 varieties of produce with 2-6 "servings" of each variety (e.g., 1 melon, 4 apples, 1 head of lettuce, 2 lbs potatoes, etc).

Our objective is to optimize the contents of the “Small Bin”. The decision we want to make is how much of each variety do …

A Systems-Based Framework For Design And Analysis Of An R And D Structure, Polinpapilinho F. Katina, Charles B. Keating, Luna M. Magpili

Engineering Management & Systems Engineering Faculty Publications

A critical challenge for managerial effectiveness and competitive advantage in research and development (R and D) organizations is developing an appropriate structural configuration. However, in finding an appropriate structural configuration, R and D managers are faced with unprecedented levels of uncertainty, ambiguity, and accelerating complexity, coupled with demands for increased productivity. This paper develops a systems-based framework to support rigorous design, analysis, and transformation of the structure for R and D organizations. The framework development includes: (1) a review of the literature for the nature and role of the structure in R and D management; (2) setting of the R …

Forecasting Us Army Enlistment Contract Production In Complex Geographical Marketing Areas, Joshua L. Mcdonald, Edward D. White, Raymond R. Hill, Christian Pardo

Faculty Publications

Purpose: The purpose of this paper is to demonstrate an improved method for forecasting the US Army recruiting. Design/methodology/approach: Time series methods, regression modeling, principle components and marketing research are included in this paper. Findings: This paper found the unique ability of multiple statistical methods applied to a forecasting context to consider the effects of inputs that are controlled to some degree by a decision maker. Research limitations/implications: This work will successfully inform the US Army recruiting leadership on how this improved methodology will improve their recruitment process.
Practical implications: Improved US Army analytical technique for forecasting recruiting goals.

An Optimization Model For Operating Room Scheduling To Reduce Blocking Across The Perioperative Process, Amin Abedini, Wei Li, Honghan Ye

Mechanical Engineering Faculty Publications

Operating room (OR) scheduling is important. Because of increasing demand for surgical services, hospitals must provide high quality care more efficiently with limited resources. When constructing the OR schedule, it is necessary to consider the availability of downstream resources, such as intensive care unit (ICU) and post anaesthesia care unit (PACU). The unavailability of downstream resources causes blockings between every two consecutive stages. In this paper we address the master surgical schedule (MSS) problem in order to minimize blockings between two consecutive stages. First, we present a blocking minimization (BM) model for the MSS by using integer programming, based on …

Assimilation Of Tracking Technology In The Supply Chain, Rahul Basole, Maciek Nowak

Information Systems and Operations Management: Faculty Publications & Other Works

While tracking technology has become increasingly accessible, firms still struggle with deploying these technologies into the supply chain. Using the complementary perspectives of transaction cost and institutional theory, we develop an understanding of how supply network, product, and environmental characteristics jointly impact tracking technology assimilation. We empirically test our model on a global dataset of 535 supply chain executives and decision makers. The results suggest that assimilation is frequently initiated by an external stakeholder in a firm's supply chain and that firms must develop strong collaborative ties with their partners in order to take full advantage of this technology.

The Long Term Effects Of An Aging Fleet On Operational Availability And Cost: Evidence From The Us Coast Guard, Christopher W. Lavin, Robert M. Mcnab, Ryan S. Sullivan

Economics Faculty Publications

This paper empirically examines whether the aging of a fleet affects operational availability and operating cost using a unique data-set on the 117 47-foot Motor Lifeboats (MLBs) of the United States Coast Guard (USCG). Procured from 1997 to 2003, the 47-foot MLB is the standard lifeboat of the USCG and all 117 MLBs remain in service. The aging of the MLB fleet has resulted in higher annual operating costs and lower operational availability, although the nature of this relationship remains unclear. Our estimation strategy utilizes an error components estimator to examine these issues. We employ three variants of the dependent …

Sensitivity Analysis Method To Address User Disparities In The Analytic Hierarchy Process, Marie Ivanco, Gene Hou, Jennifer Michaeli

Mechanical & Aerospace Engineering Faculty Publications

Decision makers often face complex problems, which can seldom be addressed well without the use of structured analytical models. Mathematical models have been developed to streamline and facilitate decision making activities, and among these, the Analytic Hierarchy Process (AHP) constitutes one of the most utilized multi-criteria decision analysis methods. While AHP has been thoroughly researched and applied, the method still shows limitations in terms of addressing user profile disparities. A novel sensitivity analysis method based on local partial derivatives is presented here to address these limitations. This new methodology informs AHP users of which pairwise comparisons most impact the derived …

Human-Intelligence/Machine-Intelligence Decision Governance: An Analysis From Ontological Point Of View, Faisal Mahmud, Teddy Steven Cotter

Engineering Management & Systems Engineering Faculty Publications

The increasing CPU power and memory capacity of computers, and now computing appliances, in the 21st century has allowed accelerated integration of artificial intelligence (AI) into organizational processes and everyday life. Artificial intelligence can now be found in a wide range of organizational processes including medical diagnosis, automated stock trading, integrated robotic production systems, telecommunications routing systems, and automobile fuzzy logic controllers. Self-driving automobiles are just the latest extension of AI. This thrust of AI into organizations and everyday life rests on the AI community’s unstated assumption that “…every aspect of human learning and intelligence could be so precisely described …

Complex Adaptive Behavior Of Hybrid Teams, Mustafa Canan, Andres Sousa-Poza, Anthony Dean

Engineering Management & Systems Engineering Faculty Publications

The challenges in uncertain, dynamic and complex military operation environments exceed the problem-solving capabilities of individuals. Problem-solving has become a team task. These [hybrid] teams, which typically include machine and human elements, utilize autonomy and artificial intelligence to enhance the quality of actionable information and decision-making capabilities in solving complex problems. For this to be effective, shared mental models must be developed by teams. This demands adaptive behavior of team members to establish a common understanding, and its members to respond to the changes in complex dynamic environments.

In this paper, we introduce a mathematical formalization of an interaction platform …

Simulation And Optimization Of Ant Colony Optimization Algorithm For The Stochiastic Uncapacitated Location-Allocation Problem, Jean-Paul Arnaout, Georges Arnaout, John El Khoury

Engineering Management & Systems Engineering Faculty Publications

This study proposes a novel methodology towards using ant colony optimization (ACO) with stochastic demand. In particular, an optimizationsimulation-optimization approach is used to solve the Stochastic uncapacitated location-allocation problem with an unknown number of facilities, and an objective of minimizing the fixed and transportation costs. ACO is modeled using discrete event simulation to capture the randomness of customers’ demand, and its objective is to optimize the costs. On the other hand, the simulated ACO’s parameters are also optimized to guarantee superior solutions. This approach’s performance is evaluated by comparing its solutions to the ones obtained using deterministic data. The results …

An Engineering Approach To Industrial Research And Development Of Pillows, Wesley Patterson

Mahurin Honors College Capstone Experience/Thesis Projects

Comfort during sleep, though taken for granted, involves a great amount of research and engineering. Few give it a second thought, but nearly one-third of a person’s life is spent with their head on a pillow, thus making them a point for increased quality. Having been approached by a tier-1 bedding manufacturer, a team of both mechanical and electrical engineers was been tasked with the goal of creating a valid research tool that the customer, Tempur-Sealy, will utilize in the company’s research and development of high-end pillows. The team sought to tackle this project utilizing tools and knowledge gained throughout …

Attending To Scientific Practices Within Undergraduate Research Experiences, Gina Quan, Chandra Turpen, Andrew Elby

Faculty Publications

Ford (2015) argues for viewing “scientific practice” not as a list of particular skills, but rather, more holistically as “sets of regularities of behaviors and social interactions” among scientists. This conceptualization of scientific practices foregrounds how they meaningfully connect to one another and are purposefully employed in order to explain nature. We apply this framework in the context of undergraduate research experiences (UREs) to understand the early forms of student engagement in scientific practices, and how these specific forms of engagement may be consequential for students’ future participation. Using video from interviews with students and research mentors, we argue that …

An Integrated Strategy For A Production Planning And Warehouse Layout Problem: Modeling And Solution Approaches, Guoqing Zhang, Tatsushi Nishi, Sarina D. O. Turner, Keisuke Oga, Xindan Li

Mechanical, Automotive & Materials Engineering Publications

We study a real-world production warehousing case, where the company always faces the challenge to find available space for their products and to manage the items in the warehouse. To resolve the problem, an integrated strategy that combines warehouse layout with the capacitated lot-sizing problem is presented, which have been traditionally treated separately in the existing literature. We develop a mixed integer linear programming model to formulate the integrated optimization problem with the objective of minimizing the total cost of production and warehouse operations. The problem with real data is a large-scale instance that is beyond the capability of optimization …

Job Sequencing In A Miniload System, Lennart Baardman, Kees Jan Roodbergen

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

More and more warehouses shift towards the use of automated systems. One such system is a miniload system. In this system, a crane retrieves bins from their storage locations and brings the bins to the picking station, where a worker takes the requested products from the retrieved bins. After a product has been picked, the bin is put back by the crane in its original location. A buffer is present at the picking station to absorb fluctuations in speed between the picker and the crane. The problem of scheduling jobs in this system has received little attention in the literature. …

Throughput Rate Of A Two-Worker Stochastic Bucket Brigade, Yossi Bukchin, Eran Hanany, Eugene Khmelnitsky

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Work-sharing in production systems is a modern approach that improves throughput rate. Work is shifted between cross-trained workers in order to better balance the material now in the system. When a serial system is concerned, a common work-sharing approach is the Bucket-Brigade (BB), by which downstream workers sequentially take over items from adjacent upstream work- ers. When the workers are located from slowest-to-fastest and their speeds are deterministic, it is known that the line does not suffer from blockage or starvation, and achieves the maximal theoretical throughput rate (TR). Very little is known in the literature on stochastic self-balancing systems …

Transport Items And Physical Internet Handling Boxes: A Comparison Framework Across Supply Chains, Eric Ballot, Benoit Montreuil

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Pallets, cardboard boxes, and plastic crates are widely used tools to operate supply chains. As such they have many impacts on handling effort, shipment protection, transport mean utilization as well as repositioning and recycling efforts and they represent billions of assets spread all over the world. The historical and local origins of the designs and the sharing among many stakeholders do not ensure at all any kind of global optimization. The purpose of this paper is to define and explain a research effort to better measure and evaluate the efficiencies and inefficiencies for supply chain stakeholders for themselves and globally. …

Continuous Approximation Of Multi Cycle Time For Multi Aisles Automated Storage And Retrieval Systems., Yassine Boudghene Stambouli, Latefa Ghomri

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Knowing that, in an automated storage and retrieval system, the travel time of the storage/retrieval machine is an important parameter which affects the whole system performances, several works were dedicated to its evaluation and its modeling, in single, dual and multi command. These models were proposed for different configurations of AS/RS; such as unit load, multi-aisles and Mobile Racks. These models are based mainly on a discrete approach and the analytical expressions represent the system functioning exactly. In this paper we present a general approach for analytical modeling of multi command cycle time by giving particularly the modeling of the …

Performance Comparison Of Automated Warehouses Using Simulation, Nand Kishore Agrawal, Sunderesh S. Heragu, Chinnatat Methapatra

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

The purpose of this study is to compare the performance of two types of warehouses, both of which use autonomous vehicles (AVs). One warehouse uses movable racks (MR) for storing mini-loads, whereas the other uses fixed racks (FR). In general, warehouse automation not only increases the speed of the fulfillment process but also makes the picking process more accurate. We simulate three scenarios for the MR and FR systems using Simio. Four performance measures are considered for the comparison – the average order processing time (WR), the average utilization of AVs (U), the average order processing queue length (Nq) and …

Dual-Tray Vertical Lift Modules For Fast Order Picking, Daria Battini, Martina Calzavara, Alessandro Persona, Fabio Sgarbossa

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

In the last years, new solutions for order picking systems have been developed both from industry and academics, especially for small items. They include innovative flexible automatic parts-to-picker systems and optimized picker-to-parts ones. One of these solutions consists in the use of Vertical Lift Modules (VLMs), a storage column in which small items are stored in extractable trays. In this paper, we study a new system composed by dual-tray VLMs where the operators perform picking and sorting activities. We propose several actions in order to improve the productivity of the entire system: 1) class based storage assignment of items inside …

A High-Density, Puzzle-Based System For Rail-Rail Container Transfers, Kevin Gue

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

We describe a high-density, puzzle-based storage and transfer system for containers in a rail-to-rail hub for the Physical Internet. The system uses a new algorithm called GridHub, which is able to transfer items in all four cardinal directions simultaneously within a grid. We show how the GridHub system might be used in a rail-rail transfer hub to transfer containers between one side of the grid and a train.

Energy And Cycle Time Efficient Warehouse Design For Autonomous Vehicle-Based Storage And Retrieval System, Banu Yetkin Ekren, Tone Lerher

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

This study explores the best warehouse design for an autonomous vehicle based storage and retrieval system (AVS/RS) minimizing average energy consumption per transaction and average cycle time per transaction, simultaneously. In the design concept, we consider, rack design in terms of number of bays, number of tiers, number of aisles; number of resources, namely number of autonomous vehicles and lifts and; velocity profiles of lifts and autonomous vehicles in the AVS/RS. We completed 1,296 number of experiments in simulation to obtain Pareto solutions representing the “average energy consumption per transaction” and “average cycle time per transaction” trade-offs based on designs …

Introducing The Concept Of Hyperconnected Mobile Production, Suzanne Marcotte, Benoit Montreuil

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Many globalized businesses are trying to cope with growing competition by strategically expanding their dedicated network of production facilities so as to be able to offer and to deliver time and price competitive offers to their clients across the world. In this paper, exploiting Physical Internet principles, we introduce the concept of hyperconnected mobile production that can alternatively enable businesses to dynamically expand and contract as necessary their production capacity in regions worldwide. First, hyperconnected mobile production exploits open fabs from multiple parties readily available in those regions. Second, these fabs are to rely on plug-and-play production modules. These modules …

A Novel Approach To Analyze Inventory Allocation Decisions In Robotic Mobile Fulfillment Systems, Tim Lamballais, Debjit Roy, M.B.M De Koster

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

The Robotic Mobile Fulfillment System is a newly developed automated, parts-to-picker material handling system. Storage shelves, also known as inventory pods, are moved by robots between the storage area and the workstations, which means that they can be continually repositioned during operations. This paper develops a queueing model for optimizing three key decision variables: (1) the number of pods per product (2) the ratio of the number of pick to the number of replenishment stations, and (3) the replenishment level per pod. We show that too few or too many pods per product leads to unnecessarily long order throughput times, …

A Scalable Algorithm For Locating Distribution Centers On Real Road Networks, Saeed Ghanbartehrani, Jose D. Porter

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

The median problem is a type of network location problem that aims at finding a node with the total minimum demand weighted distance to a set of demand nodes in a weighted graph. In this research, an algorithm for solving the median problem on real road networks is proposed. The proposed algorithm, referred to as the multi-threaded Dijkstra’s (MTD) algorithm, is then used to optimally locate Wal-Mart distribution centers on the 28-million node road network of the United States with the objective of minimizing the total demand weighted transportation cost. The resulting optimal location configuration of Wal-Mart distribution centers improves …

A Simulation Model To Evaluate The Layout For Block Stacking Warehouses, Shahab Derhami, Jeffrey S. Smith, Kevin R. Gue

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Storing pallets of Stock Keeping Units (SKU's) on top of another in lanes on a warehouse floor is known as block stacking. This storage system is widely used in manufactoring systems and distribution centers. The arrangement of lanes in the layout of this system significantly impacts utilization of the storage space and transportation costs. Existing research that studies the layout for this system focuses exclusively on determining the optimal lane depth with respect to space utilization and ignores transportation costs. In this study, we develop a stimulation model that computes several performance metrics to evaluate both of these objectives for …

Non-Traditional Aisle Design For A Manufacturing Facility Layout, Dale T. Masel, Dean Marinchek

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Methods for designing a facility layout typically assume that the aisles for interdepartmental travel will be parallel to the exterior walls of the facility. However, by putting aisles at an angle to the exterior walls, more direct routes between departments can be created, reducing travel distance. This paper describes a method to create a facility layout that does not have orthogonal aisles and testing of the resulting layouts shows that travel distance is reduced.

Toward An Engineering Discipline Of Warehouse Design, Leon Mcginnis, Timothy Sprock

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Warehouses today are complex dynamic engineered systems, incorporating automation, mechanization, equipment, fixtures, computers, networks, products and people, and they can support the flow of tens or hundreds of thousands of different items to enable fulfilling thousands or tens of thousands of orders daily. In that sense, they represent a design challenge that is not terribly different from the design of other complex dynamic engineered systems, such as a modern passenger airplane, an automobile, or a unique building. What is different is that the design of these other complex dynamic engineered systems typically follows some engineering design discipline. Here, we argue …

Understanding Worker Blocking And The Design Process, Russell D. Meller, Lisa M. Thomas

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Designing a distribution center (DC) is a complex process that consists of answering dozens of interrelated questions. From our perspective, the penultimate question is one of which picking methodology is optimal. To answer this question requires a full evaluation of picking methodologies in terms of their ability to meet the expected throughput requirements of the system. In manual picking systems, as throughput requirements increase, worker interaction and blocking increase as well. This implies that being able to estimate the amount of worker blocking in a system is critical to a design effort. Most of the prior research in this area …

Logistics Models To Support Order-Fulfillment From The Sea, Jennifer Pazour, Ian Shin

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Sea based logistics use maritime platforms to transfer cargo stored on vessels and delivers them ashore. This chapter describes the motivations and logistical requirements of seabasing. The sea base’s organizational structure, its material handling environment, and the internal cargo flow processes of the T-AKE vessel are described. Three seabasing distribution network scenarios -- Iron Mountain, Skin-to-Skin Replenishment, and Tailored Resupply Packages -- are described and mapped to warehousing and distribution networks, characteristics, and decision problems. Finally, related literature is reviewed and open areas for logistics research to support order fulfillment from the sea are identified.