Informs Annual Meeting 2017

TC12

INFORMS Houston – 2017

3 - Optimal Workload Management During a Physician’s Shift in Emergency Departments Zhankun Sun, City University of Hong Kong, 7-242, 7/F, Academic 3, Tat Chee Avenue, Kowloon Tong, Hong Kong, zhanksun@cityu.edu.hk, Nan Liu ED physicians can dynamically adjust their workload to reduce patient handovers which raise safety concerns due to the discontinuation of care. We present a dynamic programming model to inform patient flow management during a single ED physician’s work shift. Our results can help understand physician’s strategic choice of idling at the end of the shift and provide decision support. 4 - Managing EMS Systems with User Abandonment in Emerging Economies Lavanya Marla, The University of Illinois, lavanyam@illinois.edu, Kaushik Krishnan Sarang Deo (sarang_Deo@isb.edu) Abstract: We introduce, and consider an issue specifically seen in Emergency medical Services in emerging economies, called in-service abandonment. Due to resource constraints in the system, patients have a limited willingness to wait for ambulances. Because actual wait times are censored in the data, we build a maximum likelihood estimation to estimate the waiting times based on the Proportional Hazards Model. We employ a simulation-based greedy optimization approach to find good allocations to match the demand waiting time estimates, and demonstrate that policy changes that simply re-arrange ambulances at the current bases, increase fleet size or dispatch policy are unlikely to cause significant gains. Instead, we posit, and demonstrate using the data, that re-designing the base set using a huge optimization model that considers each street corner as a base, allows us to identify better base locations for ambulances. We demonstrate that the new system design matches the demand profiles better, decreasing inefficiencies in the system due to abandonment. 332B Inventory Control with Additive Manufacturing Sponsored: Manufacturing & Service Oper Mgmt Sponsored Session Chair: Rob Basten, Eindhoven University of Technology, Eindhoven, 5600 MB, Netherlands, R.J.I.Basten@tue.nl Chair: Jing-Sheng Jeannette Song, Duke University, Durham, NC, 27708-0120, United States, jssong@duke.edu 1 - Improving Effectiveness of Spare Parts Supply by Additive Manufacturing as Dual Sourcing Option Nils Knofius, University of Twente, Enschede, Netherlands, n.knofius@utwente.nl, Matthieu van der Heijden, Andrei Sleptchenko, Henk Zijm We discuss the value of sourcing spare parts with a combination of additive manufacturing (AM) and conventional manufacturing (CM) methods. In the dual sourcing literature, costs are higher and lead times are lower for the fast supply option. In our case, we also need to consider that AM parts show a different failure behavior than CM parts. As a consequence, the sourcing decision may impact future demand. Numerical experiments and a case study show that dual sourcing reinforces the value of AM methods in the low-volume, downtime- critical spare part business. 2 - Assessing the Impact of Additive Manufacturing on Spare Parts: An Inventory Management Perspective Jakob Heinen, Kuehne Logistics University, Grosser Grasbrook 17, Hamburg, 20457, Germany, johannes.jakob.heinen@the-klu.org, Kai Hoberg Spare parts are often identified as a relevant application area for additive manufacturing. Characterized by relatively low demand over long periods, additive manufacturing has the potential to reduce inventory costs and offset higher unit production costs. We develop an approach for selecting the manufacturing technology for spare parts based on supply chain related costs and derive optimal inventory policy parameters. Using a data set for 53,457 spare parts over 9 years, we assess additive manufacturing’s potential for a leading intralogistics manufacturer. Based on an analysis by part category, a significant share of spare parts can be economically produced using additive manufacturing. 3 - Temporary Replacements of Spare Parts through Additive Manufacturing Rob Basten, Eindhoven University of Technology, Eindhoven, 5600MB, Netherlands, r.j.i.basten@tue.nl, Bram Westerweel, Geert-Jan Van Houtum When spare parts have long supply lead times, equipment may experience high downtime costs during stockouts. We propose to use additive manufacturing, i.e., 3D printing, to supply temporary replacements. Analyzing the resulting model and using empirical data leads to interesting insights. TC12

4 - Impact of Additive Manufacturing on After-sales Service Supply Chains Brian Tomlin, Tuck School of Business, Dartmouth College, 100 Tuck Hall, Hanover, NH, 03755-9000, United States, brian.tomlin@tuck.dartmouth.edu, Sang Kim In this preliminary research we study how additive manufacturing (3D printing) technology changes the incentive dynamics between a manufacturer and a supplier in after-sales service supply chains. Because spare parts needed for repairs and maintenance can be 3D printed on the fly, the importance of parts inventory management and related service offerings can be diminished. At the same time, an issue arises as to how component design licensing should be arranged between the buyer and the supplier. We investigate new challenges introduced by additive manufacturing technology through the lens of contracting and game-theoretic analysis. 332C Game Theory Contributed Session Chair: Nabeel Hamoud, University of Milwaukee, Milwaukee, WI, United States, nmhamoud@uwm.edu 1 - Disease Dynamics on a Network Game: A Little Empathy Goes a Long Way Ceyhun Eksin, Georgia Tech, 310 Ferst Drive, Cherry Emerson Building, Atlanta, GA, 30332, United States, ceyhuneksin@gatech.edu, Jeff S. Shamma, Joshua S. Weitz Individuals change their behavior during an epidemic in response to whether they and those they interact with are healthy or sick. Healthy individuals may utilize protective measures while sick individuals may adopt preemptive measures to stop disease spread to their contacts. Yet, in practice both protective and preemptive behavior come with costs. We propose a stochastic network disease game that captures the self-interests of individuals during disease spread on a network. We show that there is a critical level of concern, i.e., empathy, by the sick individuals that eradicates the disease fast while the protective measures cannot eradicate the disease without the preemptive measures. 2 - A New Incomplete Information Approach to Modeling Payment and Concession Period Bargaining in Public Private Partnership Agreements Ahmadreza Talebian, Postdoctoral Fellow, University of Memphis, 302 Eng Admin Bldg, 3795 Central Ave, Memphis, TN, 38152, United States, ataleb2@uic.edu, Sabyasachee Mishra In this study, we first propose a complete information bargaining game to understand the interactions between agents negotiating to form a P3 agreement for a smart transportation infrastructure system. Then we extent the model to an incomplete information setting, in which the public agency does not have full information about the cost information of the private agency. This is a plausible setting in the real-world as private companies often consider their financial information sensitive to profitability and thus maintain it confidential. In addition to analytically solving the problem, we perform numerical analysis and offers policy-relevant insights into the state-of-the-practice. 3 - The Role of Third Part Retailer at Designing Online Return Policies: Analytical Approach Maryam Mahdikhani, Rutgers University, 1 Washington Park, Room 442, Newark, NJ, 07102, United States, m.mahdikhani@rutgers.edu, Yao Zhao Nowadays, online retailers are competing to increase their market share, and marginal profit rate by offering more services, specifically with focusing on the return policy. Although a generous return policy will be welcome by the customers, and therefore will enhance demand in the long term, this will increase cost due to increased likelihood of return. This paper develops a cost- minimization model by considering the risk mitigation from online retailers to the third part retailers in order to obtain optimal policies. We extend the model by considering the win-win-win strategy for the online retailers, customers, and third part retailers. 4 - Network Interactions and the Social Value of Information Gowtham Tangirala, Columbia Business School, 3022 Broadway, In this paper, we study the social value of information in a standard finite-agent beauty contest setting, but allowing the agents to have asymmetric coordination motives. We show that the extent of agents’ overreaction/under-reaction to public information relative to the team-efficient benchmark depends on the details of their coordination motives. We also show that even though economies that are efficient under complete information have the same equilibrium welfare when the fundamental is common knowledge, that statement may no longer hold in the presence of incomplete information. TC13 4th Floor West, New York, NY, 10027, United States, gtangirala18@gsb.columbia.edu, Alireza Tahbaz-Salehi

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