Operations Research, Systems Engineering and Industrial Engineering Commons^™

Queueing-Inventory Models For A Two-Vendor System With Positive Service Times, Srinivas Chakravarthy, Khizer Hayat

Industrial & Manufacturing Engineering Publications

Queueing-inventory systems wherein the demands are processed with random service times have been getting a lot of attention recently. In such systems, each demand needs one or more inventory items and needs positive processing times. The inventory is generally replenished using -type policy and the lead times are assumed to be random. In this paper we introduce the concept of multiple vendors who will be responsible for the replenishment of inventory. Under the assumptions of a two-vendor system wherein the demands occurring according to a Markovian arrival process, the service times to be of phase type, and the lead times …

Optimization Model For Project Manager Assignments, Neeti Verma, Poonam Ganoskar, Pallavi Gusain, Thanvi Vemulapally, Sai Kalyan, Bala Krishnamoorthy, Sai Kalyan Krishna Gali

Engineering and Technology Management Student Projects

The main objective of every project in an organization is to maximize its profit. This maximization of profit can be achieved through proper allocation of project managers to projects in an organization. But assigning a project to a project manager is still considered a difficult issue and is not yet fully addressed in the literature. However, in high-tech industries various project assignment methodologies are used to assign project managers to multiple projects and reassignment during new-product development projects. The aim of the optimization model created in this project is to develop a framework for project assignments to project managers including …

Research In Defense Logistics: Where Are We And Where Are We Going?, George A. Zsidisin, Amanda Bresler, Benjamin T. Hazen, Keith F. Schneider, Taylor H. Wilkerson

Faculty Publications

The purpose of this paper is to provide insight on high-interest areas of research in defense-related logistics and supply chain management and opportunities for advancing theory and practice in this domain.

A Scenario-Based Parametric Analysis Of The Army Personnel-To-Assignment Matching Problem, Matthew D. Ferguson, Raymond R. Hill, Brian J. Lunday

Faculty Publications

This study aims to compare linear programming and stable marriage approaches to the personnel assignment problem under conditions of uncertainty. Robust solutions should exhibit reduced variability of solutions in the presence of one or more additional constraints or problem perturbations added to some baseline problems.
Several variations of each approach are compared with respect to solution speed, solution quality as measured by officer-to-assignment preferences and solution robustness as measured by the number of assignment changes required after inducing a set of representative perturbations or constraints to an assignment instance. These side constraints represent the realistic assignment categorical priorities and limitations …

The Business Case For Industrial Safety: Revealing The Comprehensive Value Of Ergonomic Investments For Manufacturing Enterprises In Industry 4.0, Shane Stan

Honors Theses

How can today’s manufacturing enterprises construct, implement, and optimize modern safety initiatives in a manner that will present maximum return on investment and facilitate enterprise growth? Furthermore, how can these manufacturers assure individual ergonomic investments become part of a larger strategy to facilitate organizational change in safety? This work addresses these questions by placing industrial ergonomics in a business improvement context which comprehensively presents the financial returns and growth opportunities poised by modern safety initiatives. Additionally, to further strengthen the business case for industrial safety, an ergonomic action planning framework is established to guide the creation of holistic safety programs …

Data-Driven Predictive Maintenance Scheduling Policies For Railways, Pedro Cesar Lopes Gerum, Ayca Altay, Melike Baykal-Gürsoy

Supply Chain Management

Inspection and maintenance activities are essential to preserving safety and cost-effectiveness in railways. However, the stochastic nature of railway defect occurrence is usually ignored in literature; instead, defect stochasticity is considered independently of maintenance scheduling. This study presents a new approach to predict rail and geometry defects that relies on easy-to-obtain data and integrates prediction with inspection and maintenance scheduling activities. In the proposed approach, a novel use of risk-averse and hybrid prediction methodology controls the underestimation of defects. Then, a discounted Markov decision process model utilizes these predictions to determine optimal inspection and maintenance scheduling policies. Furthermore, in the …

The Impact Of Executing A Warehouse Management System Change: A Case Study, Nicholas J. Cross

Masters Theses & Specialist Projects

The increased demand on distribution centers to provide quicker turnarounds from receiving to shipping while maintaining precise inventory accuracies is spurring the acquisition of a warehouse management system (WMS) to improve operations and increase efficiency. With the rapid expansion of WMS technology, it seems inevitable that warehouses will outgrow inefficient operational processes and switch to a system that can accommodate rapid development. Research has explained the financial burdens and benefits of acquiring a WMS, but there’s been minimal research describing the impacts of the actual implementation. This study took place within a 600,000 sq. ft. fulfillment center and focused on …

Paints-R-Us Term Project, Tyler Campbell, Skye Gilbreth, Michael Oluwole, Elijah Raffo, Brad Unruh

Engineering and Technology Management Student Projects

This project will consider a linear product mix optimization problem for a fictional paint company, Paints-R-Us. Paints-R-Us is a wholesale paint manufacturer located in the Pacific Northwest. The Global Production Manager, Steve Brush, has been tasked with maximizing Paints-R-Us’s profit in the upcoming quarter. Steve Brush oversees the global production plan, and in collaboration with the production planners will develop a production plan which optimizes the profits that Paints-R-Us can create in the quarter accounting for the following criteria:

• Demand in the given quarter for each of the 5 paint types that Paints-R-Us produces • The warehousing storage capacity …

Backhaul Profit Maximization Problem Instances, Yuanyuan Dong, Yulan Bai, Eli V. Olinick, Andrew Junfang Yu

Operations Research and Engineering Management

This archive contains data for the problem instances described in the technical report "An Empirical Study of Mixed Integer Programming Formulations of the Backhaul Profit Maximization Problem" by Yulan Bai and Eli V. Olinick.

An Empirical Study Of Mixed Integer Programming Formulations Of The Backhaul Profit Maximization Problem, Yulan Bai, Eli V. Olinick

Operations Research and Engineering Management

Solving an instance of the Backhaul Profit Maximization Problem (BPMP) requires simultaneously solving two problems: (1) determining how to route an empty delivery vehicle back from its current location to its depot by a scheduled arrival time, and (2) selecting a profit-maximizing subset of delivery requests between various locations on the route subject to the vehicle's capacity. We propose and test a series of enhancements to the node-arc and triples mixed integer programming formulations of BPMP found in the literature and develop a multi-criteria Composite Index Method (CIM) to evaluate the results. We find that CPLEX takes 5 to 34 …

Modeling The Economic Machine Using Bayesian Inference And Statistical Networks, And Optimal Portfolio Construction Using Operations Research, Richard Yang

ENGS 88 Honors Thesis (AB Students)

In this paper, we propose a network-based model to attempt to connect modern macroeconomic theory with real world economic observations and trends. We find that by extending macroeconomic theory with credit leveraging/deleveraging thresholds, we are able to explain economic cycles in addition to long-term growth. Furthermore, we specifically explore the growth-inflation view of the macro economy as a basis for optimal portfolio construction and efficient asset trading. Connecting our network-based macroeconomic model and our optimal portfolio construction algorithm, we create a novel macroeconomic asset-trading framework.

An Aco-Inspired, Probabilistic, Greedy Approach To The Drone Traveling Salesman Problem, Jessica Houseknecht

Senior Honors Theses

In recent years, major companies have done research on using drones for parcel delivery. Research has shown that this can result in significant savings, which has led to the formulation of various truck and drone routing and scheduling optimization problems. This paper explains and analyzes a new approach to the Drone Traveling Salesman Problem (DTSP) based on ant colony optimization (ACO).

The ACO-based approach has an acceptance policy that maximizes the usage of the drone. The results reveal that the pheromone causes the algorithm to converge quickly to the best solution. The algorithm performs comparably to the MIP model, CP …

Applications Of Optimization Modeling In Multi-Disciplinary Engineering Research, Anton F. Astner, Ekramul Haque Ehite, Yang Li, Colin Sasthav

Biosystems Engineering and Soil Science Publications and Other Works

Optimization modeling is the process of selection of the best solution to a design problem using predetermined constraints from a set of prospective solutions. Increased computing power has made optimization solvers readily available for business/research needs. For example, Microsoft Excel has a simple, but robust solver. Such solvers can model linear, nonlinear, and integer programming problems that are limited in size. This study shows the use of the optimization model solvers in various research contexts.

On Accounting For Equipment-Control Interactions In Economic Model Predictive Control Via Process State Constraints, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

Traditionally, chemical processes have been operated at steady-state; however, recent work on economic model predictive control (EMPC) has indicated that some processes may be operated in a more economically-optimal fashion under a time-varying operating policy. It is unclear how time-varying operating policies may impact process equipment, which must be investigated for safety and profit reasons. It has traditionally been considered that constraints on process states can be added to EMPC design to prevent the controller from computing control actions which create problematic operating conditions for process equipment. However, no rigorous investigation has yet been performed to analyze whether, when a …

Technological Cooperation Network In Biotechnology Analysis Of Patents With Brazil As The Priority Country, Cristiano Goncalves Pereira, Rodrigo Ribeiro Da Silva, Joao Ricardo Lavoie, Geciane Silveira Porto

Engineering and Technology Management Faculty Publications and Presentations

Purpose – The establishment of partnerships between companies, government and universities aims to enhance innovation and the technological development of institutions. The biotechnology sector has grown in recent years mainly driven by its cooperative business model. Compared to other countries, this sector is slowly advancing in Brazil, with delays in science, technology and innovation, especially in the private sector. This paper aims to examine, through social network analysis, the collaborative networks between institutions that filed patents in biotechnology – medicinal preparations from plants – whose inventions had Brazil as the priority country. Design/methodology/approach – The study of technological cooperation using …

Foundations For A Game Theoretic Framework For Agile Acquisition, Scott Rosen, Kelly Horinek, Alexander Odeh, Les Servi, Andreas Tolk

VMASC Publications

This article investigates the concept of developing a game theoretic framework that is based on the application of buyer and seller utility functions to support the bidding process in government acquisition. The results of a literature survey of utility function approaches, with potential to provide a suitable foundation to a game theory framework for acquisition, are presented. The utility function methods found most promising were further adapted and tested: the Best-Worst method, the Multi-Swing Method, and Functional Dependency for Network Analysis. To test the scalability of the approach, the Best-Worst method is applied to a larger problem to show the …

Detecting Special-Cause Variation 'Events' From Process Data Signatures, Timothy M. Young, Olga Khaliukova, Nicolas André, Alexander Petutschnigg, Timothy G. Rials, Chung-Hao Chen

Electrical & Computer Engineering Faculty Publications

The ability to detect the special-cause variation of incoming feedstocks from advanced sensor technology is invaluable to manufacturers. Many on-line sensors produce data signatures that require further off-line statistical processing for interpretation by operational personnel. However, early detection of changes in variation in incoming feedstocks may be imperative to promote early-stage preventive measures. A method is proposed in this applied study for developing control bands to quantify the variation of data signatures in the context of statistical process control (SPC). Control bands based on pointwise prediction intervals constructed from the Bonferroni Inequality and Bayesian smoothing splines are developed. Applications using …

A Multi-Response Optimization For Isomerization Of Light Naphtha, Donia Abdel Nasser Fathy, Moustafa A. Soliman

Chemical Engineering

Isomerization process is considered one of the main processes used to produce high octane rating gasoline with improved environmental conditions and less emissions. The main keys of performance in isomerization units are the product yield, paraffin isomerization number (PIN) and octane number (RON). In this article we present a multi-response optimization strategy for an industrial naphtha continuous isomerization-process that aims to maximize RON, PIN and yield. Data of 53-runs including feed compositions as well as operating conditions; reactor temperature, benzene content, liquid hour space velocity, feed PIN, hydrogen to hydrocarbon ratio, feed octane number, C7+ content, inlet reactor temperature and …

Cost Benefit Analysis Of Led Vs Florescent Lighting, Kurtis Clark, Phillip Humphrey

Student Research

Over the last few years, the state of Oklahoma has been looking at ways to reduce expenses to address concerns about a budget deficit. There have been efforts made to reduce expenses due to the use of energy. It has been said, when the lights are on, work is getting done. Running lights is therefore the cost of doing business. Our research examines the question, “is there a way to provide better lighting while operating at a lower cost.” This research examines the current lighting at Southwestern State University, primarily fluorescent lighting (FL), and a cost benefit analysis of switching …

A Mathematical Framework On Machine Learning: Theory And Application, Bin Shi

FIU Electronic Theses and Dissertations

The dissertation addresses the research topics of machine learning outlined below. We developed the theory about traditional first-order algorithms from convex opti- mization and provide new insights in nonconvex objective functions from machine learning. Based on the theory analysis, we designed and developed new algorithms to overcome the difficulty of nonconvex objective and to accelerate the speed to obtain the desired result. In this thesis, we answer the two questions: (1) How to design a step size for gradient descent with random initialization? (2) Can we accelerate the current convex optimization algorithms and improve them into nonconvex objective? For application, …

Economic Model Predictive Control Design Via Nonlinear Model Identification, Laura Giuliani, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

Increasing pushes toward next-generation/smart manufacturing motivate the development of economic model predictive control (EMPC) designs which can be practically deployed. For EMPC, the constraints, objective function, and accuracy of the state predictions would benefit from process models that describe the process physics. However, obtaining first- principles models of chemical process systems can be time-consuming or challenging such that it is preferable to develop physics-based process models automatically from process operating data. In this work, we take initial steps in this direction by suggesting that because experiments that are used to characterize first-principles models often target specific types of data, an …

Data-Based Nonlinear Model Identification In Economic Model Predictive Control, Laura Giuliani, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

Many chemical/petrochemical processes in industry are not completely modeled from a first-principles perspective because of the complexity of the underlying physico-chemical phenomena and the cost of obtaining more accurate, physically relevant models. System identification methods have been utilized successfully for developing empirical, though not necessarily physical, models for advanced model-based control designs such as model predictive control (MPC) for decades. However, a fairly recent development in MPC is economic model predictive control (EMPC), which is an MPC formulated with an economics-based objective function that may operate a process in a dynamic (i.e., off steady-state) fashion, in which case the details …

Pricing Policies For A Dual-Channel Retailer With Cross-Channel Returns, Mohannad Hassan Radhi, Guoqing Zhang

Mechanical, Automotive & Materials Engineering Publications

Many retailers are adopting a dual-channel retailing strategy (DCRS) in which products are offered through two channels: physical stores and online stores. Due to regulations or competitive measures, such a strategy allows customers who find a purchase unsatisfactory to obtain a full refund through a same-channel return or a cross-channel return. No papers have collectively studied the aforementioned types of customer returns in a dual-channel context. This paper studies optimal pricing policies for a centralized and decentralized dual-channel retailer (DCR) with same- and cross-channel returns. How dual-channel pricing behavior is impacted by customer preference and rates of customer returns is …

Repeatability Case Study Of The 3d Printer In The School Of Engineering And Applied Science Lab, Naif Faleh S. Albaiji

Masters Theses & Specialist Projects

3DP (three-dimensional printing) technologies have become more than just a tool to help companies with prototyping and designing in the pre-production stage. Some firms have already implemented 3DP technology to produce parts and end-use products. However, there are several challenges and barriers that this technology must overcome to replace traditional manufacturing methods. One of the most significant obstacles associated with 3D printing is its low level of accuracy in variable repeatability when it comes to making separate batches of the same product. There are several arguable reasons behind this variation. Some of the factors that can influence repeatability are the …

Implementing A Total Productive Maintenance Approach Into An Improvement At S Company, Xiaomeng Sun

Masters Theses & Specialist Projects

The study improved the overall equipment effectiveness (OEE) of machines and processes through the implementation of a total productive maintenance (TPM) approach at Company S over a three-month period. By comparing the OEE of equipment before and after the implementation of autonomous maintenance, this study concluded that autonomous maintenance improves OEE. The target of this study was one general product line at a polytetrafluoroethylene (PTFE) plant. Due to time limitations, the study only applied autonomous maintenance to operational activities. This research involved machine and processes selection, condition assessment, baseline OEE assessment, operator training, execution of autonomous maintenance, and OEE measurement. …

Dual-Channel Warehouse And Inventory Management With Stochastic Demand, Fawzat Alawneh, Guoqing Zhang

Mechanical, Automotive & Materials Engineering Publications

This study examines the inventory policy for the emerging dual-channel warehouse, which has a unique structure where the warehouse is divided into two areas: one for fulfilling online orders and the other for storing products and fulfilling offline orders. A multi-item inventory model was developed considering the warehouse capacity constraint, demand, and lead time uncertainty. Solution methods are provided for both uniform and normal distributions. Adopting the proposed inventory policy for a dual warehouse is cost effective and adds flexibility to the warehouse and supply chain. The study also offers managerial insights on some critical issues faced by companies operating …

Shift Scheduling Optimization For Psu Library, Aayushi Gupta, Anju Babu, Lipishree Vrushabhendra, Shivani Purwar, Shravankumar Doosa

Engineering and Technology Management Student Projects

Scheduling is important in any business as it creates an order and flow ensuring that all the tasks are covered at appropriate times. According to experts, scheduling determines the economics of a job, the quality of the team, and the skill-building and motivation of professionals doing the work. Therefore, it is essential to have optimized staff schedules to meet the requirements of staff availability, tasks coverage, shift equity and staff preferences. Though staff scheduling is of such prime importance, it is mostly implemented in traditional ways of manually creating spreadsheets and web calendars proving to be laborious and often leaving …

Minimizing Commute Distance For Small Groups: A Linear Programming Approach, Kevin Payne, Kritika Kumari, Levi Huddleston, Rabi Hassan

Engineering and Technology Management Student Projects

This paper aims to minimize total drive time between members and their respective group leader. Given a limit on group size and days available, how can a formulation of a group occur such that the sum of the total drive time is minimized. To accomplish this task a Linear Program (LP) is implemented that includes three sets of binary decisions variables summing to 4100 variables and a variety of constraints summing between 4200 and 4341 depending on the constraints enforced. For 200 members and 15 leaders the minimized average commuting time was found to be between 4.99 and 5.36 minutes …

Stochastic Bi-Level Optimization Models For Efficient Operating Room Planning, Amin Abedini, Wei Li, Honghan Ye

Mechanical Engineering Faculty Publications

Within a hospital, the operating room (OR) department has the largest cost and revenue. Because of the aging population, the demand for surgical services has been increasing sharply in recent years. At the other hand, the rate of OR capacity expansion is lower than the rate of increasing demand. As a result, OR managers must leverage their resources by efficient OR planning. OR planning is challenging because of multiple competing\conflicting objectives such cost minimization and throughput maximization. Inherent uncertainty in the surgical procedures and patients arrivals complicate the decision making process. This increases the risk of non-realization of the system …

A Design Methodology To Optimize Supply Chain Network Performance, Dheeraporn Nippaya, J. David Porter

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Organizations are constantly looking for new ways to reduce costs while still providing high customer service levels to face stringent competitive environments and the ever- increasing market globalization. An alternative these organizations can pursue to respond to these challenges and to gain a competitive differentiation is to optimize their supply chain network (SCN). This research aims to develop an effective SCN design strategy to locate facilities (i.e., plants and distribution centers) and to balance the allocation of customers to these facilities to satisfy capacity limitations and customer demands with minimum total cost and maximum level of service. It is anticipated …