Informs Annual Meeting Phoenix 2018

INFORMS Phoenix – 2018

MD34

4 - Optimum Placement of Actuators for Large Space Structure Shape Control Juan Du, Peking University, College of Engineering, 5 Yiheyuan Road, Beijing, 100871, China, Xiaowei Yue, Jianjun Shi Shape control of large space structure is critical for the usage functionality. To realize large space structure shape adjustment, actuators are essential tools. Given the fixed number of actuators, different actuator placements influence the shape control capability. Optimization of actuators’ placements is very important but challenging . This presentation proposes an automatic actuator placement approach for efficient large space structure shape control by developing a sparse learning model and corresponding estimation algorithm. The case study shows that our proposed method achieves good performance for shape adjustments of large space structure. n MD34 North Bldg 223 4:30 - 5:15 AMPL/ 5:15-6:00 Didi Chuxing Vendor Workshop Session 1 - Model-Based Optimization + Application Programming = Streamlined Deployment in AMPL Robert Fourer, AMPL Optimization Inc., 2521 Asbury Ave, Evanston, IL, 60201, United States, Filipe Brand π o AMPL offers the advantages of modeling in a specialized optimization environment combined with the power of application development via general- purpose programming. Optimization problems are formulated concisely and naturally in AMPL’s modeling language, promoting rapid development, reliable maintenance, and evaluation of multiple solvers and data sources. APIs for popular full-featured programming languages facilitate embedding of AMPL models and scripts into complex applications, with access to data management and interface development libraries. We illustrate using AMPL’s APIs for Python and R, and conclude with a preview of features for invoking Python within AMPL scripts. 2 - Ride-sharing Services Research at Didi Chuxing Didi Chuxing, Didi Chuxing, Beijing, China Didi Chuxing is the world’s leading mobile transportation platform. The company offers a full range of mobile tech-based mobility options for nearly 400 million users. As many as 20 million rides were completed on DiDi’s platform on a daily basis, making DiDi the world’s second largest online transaction platform. DiDi acquired Uber China in August 2016. DiDi is committed to working with communities and partners to solve the world’s transportation, environmental and employment challenges using big data-driven deep-learning algorithms that optimize resource allocation. In 2016, Didi was named one of the World’s 50 Smartest Companies by MIT Technology Review. n MD35 North Bldg 224A AAS Special Invited Speaker Presentation Sponsored: Aviation Applications Sponsored Session Chair: Heng Chen, University of Nebraska-Lincoln, Lincoln, NE, 68588, United States Chair: Vikrant Vaze, Dartmouth College, 14 Engineering Drive, Murdough Center, Hanover, NH, 03755, United States 1 - The Dawn of Urban Aerial Ridesharing Jon Petersen, Uber, San Francisco, CA, United States With 2/3 of the world’s population expected to live in cities within 25 years there is an upper bound to what can be done to improve urban mobility on the ground. Technological advancements from vehicles, batteries, airspace, infrastructure, and multimodality are converging to generate a new mode of urban transportation that utilize the third dimension. This talk will introduce the Uber Elevate ecosystem and specifically focus how optimization and machine learning are being used to model demand, construct networks within cities, define vehicle and infrastructure requirements, and build out and scale urban aerial ridesharing beginning in 2023.

n MD36 North Bldg 224B Topics in Healthcare Provider Productivity & Satisfaction Sponsored: Manufacturing & Service Oper Mgmt/Healthcare Operations Sponsored Session Chair: Robert Batt, Wisconsin School of Business, UW-Madison, Madison, WI, 53706, United States 1 - The Impact of Shift Changes on Medication Ordering and Delivery in the Intensive Care Unit Lesley Meng, The Wharton School, University of Pennsylvania, 3730 Walnut Street, Suite 500 JMHH, Philadelphia, PA, 19104, United States, Ann M. Huffenberger, Krzysztof Laudanski, Christian Terwiesch Patients spending time in the intensive care unit (ICU) of a hospital are often there to receive stabilizing, life-saving care. Providers working in this environment must pay careful attention to medication delivery so that these patients may recover as quickly as possible without complications. We utilize a comprehensive dataset consisting of all ICU patient visits across 3 academic teaching hospitals over 5 years to study the accuracy of medication orders and the timing of medications delivered. 2 - Mixing It Up: Operational Impact of Hospitalist Workload Masoud Kamalahmadi, Indiana University, 1309 E. 10th Street Room HH 4100, Bloomington, IN, 47405, United States, Alex Mills, Jonathan Helm, Kurt M. Bretthauer Hospitalists are physicians that specialize in caring for hospital inpatients, replacing a primary care physician who may only make rounds once per day and thereby reducing delays. Given a limited number of hospitalists in a hospital, we seek to determine their optimal service mix (workload and patient types). 3 - Customized Office Revisit Intervals and Evisits in Primary Care Hessam Bavafa, Wisconsin School of Business, 4284C Grainger Hall, 975 University Avenue, Madison, WI, 53706, United States, Sergei Savin, Christian Terwiesch The demand for physician services in primary care is shaped by the number of patients associated with each physician and the frequency of scheduled office visits. While a physician can typically set the size of her patient panel without regard for individual patient preferences, office revisit intervals are determined jointly by the physician and her patients. In our model, a physician can manage the demand for her services using two “customization approaches: (1) adjusting the office revisit intervals based on patient health status, and (2) diverting some of the patient demand away from the office visits and into “e-visitsö. 4 - Payment Mechanisms, Incentives for Adoption and Value of Health-information Exchanges (HIEs) Mehmet Ayvaci, University of Texas-Dallas, Richardson, TX, United States, Huseyin Cavusoglu, YeongIn Kim, Srinivasan Raghunathan Diffusion of health information outside the boundaries of an organization through health-information exchanges (HIEs) is a critical step in achieving socially desirable care outcomes. In this paper, we study the relationships among a payment model, providers’ incentives to adopt HIEs, and the value of HIEs using a game-theoretical model. We demonstrate that ssessing the value of HIEs in isolation from the underlying payment mechanism and patient switching behavior may result in under- or overestimation of the HIE value. Therefore, as payment models evolve over time, there is a real need to reevaluate the value of HIE adoption and the government policies that induce providers to adopt HIE.

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