Informs Annual Meeting 2017

TB43

INFORMS Houston – 2017

2 - Data Analytics and Optimization for Efficient E-warehousing Ugur Yildiz, University of Waterloo, Waterloo, ON, Canada, uyildiz@uwaterloo.ca, Fatma Gzara, Samir Elhedhli We analyze data from an e-commerce warehouse, characterized by high product variety and small order sizes, to model the order fulfillment process and identify areas of improvement. We focus on the order consolidation process and pose a problem that we call the Wave Sorting Problem. We provide models and solution methodologies based on column generation where the subproblem is solved using dynamic programming. 3 - A Novel, Dynamic Sparse Classification Approach for Online Monitoring of the Functional Properties of Printed Electronics in Aerosol Jet Printing Process Roozbeh Salary, Ph.D. Candidate and Graduate Research Assistant, State University of New York (SUNY) at Binghamton, 25 Tracy Street, Binghamton, NY, 13905-1841, United States, rsalary1@binghamton.edu, Jack P. Lombardi, Mohammad Samie Tootooni, Darshana L. Weerawarne, Prahalad K. Rao, Mark D. Poliks The goal of this work is online monitoring (and ultimately, closed-loop control) of the functional properties of aerosol jet-printed electronic devices. In pursuit of this goal, the objective is to develop a multiple-input, single-output (MISO) machine learning model to predict the device functional properties in a real-time fashion as a function of process parameters as well as 2D/3D morphology characteristics. The aim is to use the MISO model for in situ classification and thus, monitoring of line/device resistance in aerosol jet printing (AJP) process. The core hypothesis of the work is that line resistance is predicted (and as a result, monitored) online within 10% of offline measurements. 360B Matching in Two-Sided Markets with Social Impact Sponsored: Public Sector OR Sponsored Session Chair: Ozlem Ergun, Northeastern University, Boston, MA, 02115, United States, o.ergun@neu.edu Co-Chair: Tina Rezvanian, Northeastern University, Boston, MA, 02115-4420, United States, rezvanian.t@husky.neu.edu 1 - KUDU: A Mobile Market for Agricultural Trade in Uganda Neil Newman, University of British Columbia, Vancouver, BC, Canada, newmanne@cs.ubc.ca, Nicole Immorlica, Kevin Leyton-Brown, Brendan Lucier, Richard Ssekibuule, John Quinn In developing countries such as Uganda, agricultural markets exhibit inefficiencies as rural farmers have poor access to pricing information. Kudu is a two sided market for agricultural produce in Uganda seeking to address this problem using AI. Farmers and traders each submit bids to a centralized system using SMS and USSD (technologies available on non-internet-enabled phones) and a matching algorithm periodically proposes trades. This talk will discuss the challenges we have faced designing a market in this unique setting over the past four seasons of operation. 2 - Effect of Selfish Choices in Deferred Acceptance with Short Lists Hedyeh Beyhaghi, Cornell University, Ithaca, NY, United States, hedyeh@cs.cornell.edu, Daniela Saban, Eva Tardos We study the outcome of deferred acceptance when prospective medical residents can only apply to a limited set of hospitals. This limitation requires residents to make a strategic choice about the quality of hospitals they apply to. We study the effect of this strategic choice on the preferences submitted by participants, as well as overall welfare. We find that residents’ choices in our model mimic the behavior observed in real systems where individuals apply to a mix of positions consisting mostly of places where they are reasonably likely to get accepted, as well as a few “reach” applications to hospitals of very high quality, and a few “safe” applications to hospitals of lower than their expected level. 3 - Optimal Trading and Shipping of Agricultural Commodities Nicolas Stier-Moses, Universidad Torcuato Di Tella, Buenos Aires, Argentina, nstier@utdt.edu, Nicolas Merener, Ramiro Moyano, Pablo Watfi We develop a model for a profit-maximizing firm that provides an intermediation service between commodity producers and end-users. We are motivated by the grain intermediation business at Los Grobo, one of the largest commodity-trading firms in South America. Producers and end-users are distributed over a realistic spatial network, and trade with the firm through contracts for delivery of grain during the marketing season. Under realistic capacities, network structure and shipping costs, we identify the optimal trading, storing and shipping policy for the firm as the solution of a minimum cost flow problem in a time-expanded network that captures both geography and time. TB43

4 - Two-sided Stable Matching with Negotiations in Markets with Multiple Periods Tina Rezvanian, PhD, Northeastern University, Boston, MA, 02115, United States, rezvanian.t@husky.neu.edu, Ozlem Ergun It is a well-known fact that the core of match stays the same under any stable algorithms. Stable algorithms in multi-period two-sided markets come at the cost of continuous dissatisfaction for same group of agents, resulting in high turn overs, low overall welfare and ultimately, unsustainability over multiple periods. Many industries demand mechanisms that guarantee sustainability and perfect assignments over all periods. We use labor marker auction models to offer contract-like negotiations to agents, identified through a novel centrality measure that we introduce for two-sided markets. Proposed heuristic relaxes stability only to guarantee sustainability over multiple periods. 360C Marketing Contributed Session Chair: Efstratios Pistikopoulos, Texas A&M University, College Station, TX, United States, stratos@tamu.edu 1 - A Method of Exploration of the Solution Space for Decision Support in Design of a Green Supply Chain Lin Guo, University of Oklahoma, Norman, OK, United States, lin.guo@ou.edu, Warren Smith, Janet Katherine Allen, Farrokh Mistree Multi-objective optimization models have been proposed to improve supply chain design, considering social and environmental goals as well as financial goals. However, optimization models search for single optimal solution that is sensitive to variations. In this paper, we propose a multi-goal model built on the construct of compromise Decision Support Problems (cDSP) to output solution space that is relatively insensitive to variations. A method of exploration of the solution space is used to provide us the insight on how to improve the feasibility robustness of the supply chain with multiple conflict goals. 2 - Modoalgos.jl: Computing Approximate and Exact Efficient Frontiers of Multiobjective Mixed Integer Linear Programs in Julia TB44 We introduce Modoalgos.jl ( and 2 other related packages ), a Julia package capable of computing the exact and approximate frontiers of both Biobjective and Multiobjective Mixed Integer Linear Programs using state of the art algorithms. 3 - B-pop: A Multi-parametric Programming Based Toolbox for the Global Solution of Bi-level Mixed-integer Linear and Quadratic Programming Efstratios N. Pistikopoulos, Texas A&M.University, College Station, TX, United States, stratos@tamu.edu Efstratios N. Pistikopoulos, Texas A&M.Energy Institute, College Station, TX, United States, stratos@tamu.edu, Styliani Avraamidou, Styliani Avraamidou, Nikolaos A. Diangelakis We present a prototype toolbox, B-POP, a MATLAB toolbox for bi-level programming, for the exact, global and parametric solution of different classes of bi-level programming problems. The toolbox features i) bi-level programming solvers for linear and quadratic programming problems and their mixed-integer counter-parts, ii) a versatile problem generator capable of creating random bi- level problems of arbitrary size, and iii) a library of bi-level programming test problems. The toolbox is based on multi-parametric theory and our developed algorithms and software tools. A set of test problems was solved illustrating the computational performance and scalability of the toolbox. Aritra Pal, Doctoral Candidate, University of South Florida, 4202 E. Fowler Avenue, Tampa, FL, 33620, United States, aritra1@mail.usf.edu

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