4 Presentations

• 
  10:30 AM - 10:55 AM

  Control of addictive behaviors with relapsing

  • Fouad El Ouardighi, presenter, ESSEC Business School
  • Dieter Grass, Vienna Technical University

  One important consequence of addictions is the high occurrence of relapsing after treatment, which often lies between 40 and 60% depending on the kind of addiction and population (Mc Lellan et al., 2000). While the importance of prevention-treatment policies against addictions is widely acknowledged in the economic literature, the consequences of relapsing on the effectiveness of such policies remain yet under-investigated. This paper seeks to bridge the gap by introducing a dynamic model where individuals can move back and forth between active addiction and temporary abstinence. Though both states are socially costly, active addiction promotes initiation by others while temporary abstinence discourages it. Using optimal control techniques, we evaluate how the tradeoff between prevention and treatment of addiction is affected by the occurrence of relapsing. We show that the trajectories of de-escalation from the addiction can be much more complex than what is obtained in the existing literature.
• 
  10:55 AM - 11:20 AM

  Large size ambulance routing problem

  • Thierry Garaix, presenter, École Nationale Supérieure des Mines de Saint-Étienne
  • Xiaolan Xie, École des Mines de Saint-Étienne
  • Mohammed Skiredj, École des Mines de Saint-Étienne

  In this research we propose an adaptive large neighborhood search designed to solve ambulance routing problems. Good solutions are computed within 20 minutes for instances with 2000 requests, 300 drivers and crew recomposition and lunch break constraints. Experiments are conducted on instances from Hong-Kong and French medical transportation companies.

  keywords: Ambulance routing problem, Large size vehicle routing problem, Adaptive large neighborhood search
• 
  11:20 AM - 11:45 AM

  Multi-appointment, multi-stage outpatient scheduling at oncology clinics

  • Maryam Haghi, presenter,
  • Ivan Contreras,
  • Nadia Bhuiyan,

  Outpatient chemotherapy clinics are one of the most demanded multi-stage and multi-resource outpatient clinics in which patients must go through several interdependent stages. To coordinate all the required appointments of each patient properly while utilizing valuable resources efficiently, we propose an integrated model to schedule multiple appointment requests of different types of patients over a planning horizon. The proposed integrated model can be used as an online scheduling tool to accommodate arriving requests to the clinic over time. The performance of the model is evaluated using historical data obtained from a major cancer center in Canada. Furthermore, two sequential approaches are also proposed to assess the value of decisions’ integration.
• 
  11:45 AM - 12:10 PM

  Integer programming models for the breast cancer screening problem

  • Mucahit Cevik, presenter, Ryerson University

  Cost of mammography and lack of resources limit the widespread use of mammography for screening in many countries. We propose an integer programming model to investigate the breast cancer screening problem in a resource-constrained setting where the objective is to maximize total quality adjusted life years of the patients.
  Keywords: breast cancer screening; medical decision making; integer programming