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My blog, OR in an OB World, is published via Blogger. The content is a mix of tips and tricks for operations research (primarily discrete optimization), coding (Java, CPLEX, R) and Linux (especially Linux Mint), with the occasional rant mixed in.

Selected Publications

In this paper, we propose a novel 3D Underwater Wireless Sensor Network Deployment scheme for solid detection in rivers. Our objective is to minimize the number of deployed underwater sensors within a target field installation while ensuring i) the required Quality of Monitoring (QoM) (i.e., differentiated probabilistic detection) and ii) wireless network connectivity. To generate the best topology, we propose a novel deployment heuristic, named 3D-UWSN-Deploy, based on a subcube tessellation of the monitored field installation and a mixed integer linear program optimization. To gauge the effectiveness of 3D-UWSN-Deploy, we compare it with the most prominent related strategies. Simulation results show that our proposal is scalable and obtains the best performance in terms of cost deployment, quality of monitoring and connectivity.
2016 IEEE International Conference on Communications (ICC)

We present an improved formulation for the maximum coverage patrol routing problem (MCPRP). The main goal of the patrol routing problem is to maximize the coverage of critical highway stretches while ensuring the feasibility of routes and considering the availability of resources. By investigating the structural properties of the optimal solution, we formulate a new, improved mixed integer program that can solve real life instances to optimality within seconds, where methods proposed in prior literature fail to find a provably optimal solution within an hour. The improved formulation provides enhanced highway coverage for both randomly generated and real life instances. We show an average increase in coverage of nearly 20% for the randomly generated instances provided in the literature, with a best case increase over 46%. Similarly, for the real life instances, we close the optimality gap within seconds and demonstrate an additional coverage of over 13% in the best case. The improved formulation also allows for testing a number of real life scenarios related to multi-start routes, delayed starts at the beginning of the shifts, and taking a planned break during the shift. Being able to solve these scenarios in short durations help decision and policy makers to better evaluate resource allocation options while serving public.
Computers & Operations Research

This article examines the problem of assigning individuals to teams to make the teams as similar as possible to each other across multiple attributes. This may be complicated by a variety of constraints, including restrictions on whether specific individuals can or should be assigned to the same team. The problem arises in multiple contexts, including youth recreation leagues and academic programs or courses with mandated project groups. A model for the problem is proposed and various solution approaches are investigated, including mixed-integer programming and several heuristics. Supplementary materials are available for this article. Go to the publisher’s online edition of IIE Transactions for datasets, additional tables, detailed proofs, etc.
IIE Transactions

Publications

More Publications

  • A Novel 3D Underwater WSN Deployment Strategy for Full-Coverage and Connectivity in Rivers

    Details

  • An improved formulation for the maximum coverage patrol routing problem

    Details

  • Forming Competitively Balanced Teams

    Details Dataset Discussion & Software

  • Combinatorial Benders Cuts for the Minimum Tollbooth Problem

    Details

  • Linear Programming Models for Classification

    Details

  • Mixed Integer Classification Problems

    Details

  • A Heuristic Procedure for Sequence Dependent Scheduling with Stock Cutting

    Details

  • Scheduling and Sequencing with Stock Cutting Considerations

    Details

  • Comment on “A Nonlinear Lagrangian Dual for Integer Programming”

    Details

  • Oscillation Heuristics for the Two-group Classification Problem

    Details

Recent & Upcoming Talks

Teaching

In my time in the Department of Management at Michigan State University, I taught the following courses. (This list excludes courses taught as a graduate teaching assistant in the Department of Mathematics.)

Undergraduate (junior/senior) courses

  • MGT 304: Operations Planning and Control (production management)
  • MGT 306: Analysis of Processes and Systems (quantitative methods)
  • MGT 325: Management Skills (organizational behavior)

MBA courses

  • MBA 804: Applied Data Analysis (statistical methods, primarily time series analysis)
  • MBA 841: Studies in the Global Marketplace (international field trip)
  • MGT 805: Special Topics in Management (elective course in optimization and simulation)
  • MGT 808: Database Management Systems (nontechnical introduction to DBMS)
  • MGT 820: Managing the Internetworked Firm (seminar on Internet technology and governance as it relates to business use of the Internet)
  • MGT 821: Managing Internet Commerce (design of Internet applications, including hands-on experience building a simple web application)
  • MGT 831: Computers and Systems Analysis in Business (introduction to computer systems)
  • MGT 832: Introduction to Business Statistics (a first course in statistics)
  • MGT 833: Decision Support Models (core course in quantitative methods)
  • PIM 850: Analysis and Decision Modeling (online course in statistical methods)

MS/MBA/PhD courses

  • MGT 834: Linear Optimization Models (linear programming theory and practice)
  • MGT 835: Nonlinear Optimization Models (nonlinear programming)
  • MGT 835: Advanced Optimization Models (network and discrete optimization)
  • MGT 836: Applied Stochastic Processes (Markov chains, queueing systems, …)
  • MGT 837: Systems Simulation (discrete event simulation models and methods)
  • MGT 890: Seminar in Advanced Optimization Methods (dynamic and stochastic linear programming)
  • MGT 914: Applied Regression Models in Business Research (doctoral seminar in linear, nonlinear and logistic regression)
  • MGT 921: Seminar in Inventory Theory (research themes in inventory theory)
  • MSC 990a: Analytical Research Methods in Operations Management (doctoral seminar on optimization models in OM)

Contact

Miscellany

My filing system tends to be “heap sort”.

heap sort

An old photo of myself having a beer with my Evil Twin. (I’m the good-looking one.)

beer with Evil Twin

At the MIP 2015 workshop, I was once again low man on the totem pole (or, in this case, bottom right in the pyramid).

MIP 2015 pyramid

I’m the one in red, delivering a roundhouse kick you can’t see, in a match at the 2007 Great Lakes Cup (geezer division). I lost the match, though. (The judges robbed me, of course.)

Great Lakes Cup 2007