Applied Stochastic and Statistical Modelling Lab (SSL)

Vahid Sarhangian Associate Professor, Mechanical & Industrial Engineering Director, Centre for Healthcare Engineering (CHE) Email: sarhangian AT mie DOT utoronto DOT ca Homepage: https://sarhangian.mie.utoronto.ca/ Campus Phone: (416) 978 – 4020 Office Location: BA8108 (Bahen Centre), 40 St George St, Toronto, ON M5S 2E4

About me

I am an Associate Professor at the Mechanical and Industrial Engineering (MIE) department, and the Director of the Centre for Healthcare Engineering (CHE) at the University of Toronto. I did my PhD studies in Operations Management and Statistics at the Rotman School of Management at University of Toronto. Before joining MIE, I was a Postdoctoral Research Scholar at the division of Decision, Risk, and Operations at Columbia Business School.

My current research focuses on data-driven modelling and control of stochastic dynamical systems that arise in healthcare operations and supply chain management.

Research

• Working papers
  1. T. C. Y. Chan, J. Park, V. Sarhangian, Robust confidence bands for stochastic processes using simulation.
  2. T. C. Y. Chan, J. Park, V. Sarhangian, Dynamic transfer policies for parallel queues.
     • Jangwon Park: Second place, 2024 CORS Queueing and Applied Probability SIG Student Paper Competition
  3. H. Abouee-Mehrizi, M. Mirjalili, V. Sarhangian, Platelet inventory management with approximate dynamic programming.
  4. P. Afeche, J. Hu, R. Ibrahim, V. Sarhangian, The effects of information granularity on abandonment and congestion in non-stationary priority queues.
  5. T. C. Y. Chan, J. Park, F. Pocagar, V. Sarhangian, E. Hellsten, F. Razak, A. Verma, Optimizing inter-hospital patient transfer decisions during a pandemic: a queueing network approach.
     • Jangwon Park: First place, 2024 CORS Healthcare SIG Student Paper Competition
  6. P. Afeche, V. Sarhangian, Rational abandonment from priority queues: equilibrium strategy and pricing implications.

• Published/Accepted papers
  1. T. C. Y. Chan, S. Y. Huang, V. Sarhangian, Dynamic control of service systems with returns: Application to design of post-discharge hospital readmission prevention programs. Operations Research, Forthcoming. [code]
  2. J. Chan, B. Gorgulu, V. Sarhangian, Inventory management with advance booking information: the case of surgical supplies and elective surgeries, Manufacturing & Service Operations Management, 2024.  [code]
  3. J. Dong, B. Gorgulu, V. Sarhangian, What causes delays in admission to rehabilitation care? a structural estimation approach, Manufacturing & Service Operations Management, 2024.
  4. R. Stephenson, V. Sarhangian, J. Park, A. Sankar, N. N. Baxter, T. A. Stukel, A. N. Simpson, D. N. Wijeysundera, A. S. Wilton, C. de Mestral, S. W. Hang, D. Pincus, R. J. Campbell, D. R. Ubrach, J. Irish, D. Gomez, T. C. Y. Chan, “Evolution of the surgical procedure gap during and after the COVID-19 pandemic in Ontario, Canada: cross-sectional and modelling study“. British Journal of Surgery, 2023.
  5. M. Mirjalili, H. Abouee-Mehrizi, R. Barty, N. M. Heddle, V. Sarhangian, A data-driven approach to determine daily platelet order quantities at hospitals. Transfusion, 2022.
  6. C. W. Chan, V. Sarhangian, P. Talwai, K. Gogia, Utilizing partial flexibility to improve emergency department flow: theory and implementation. Naval Research Logistics, 2022.
  7. H. Abouee-Mehrizi, M. Mirjalili, V. Sarhangian, Data-driven platelet inventory management under uncertainty in the remaining shelf-life of units. Production and Operations Management, 2022.
  8. B. Gorgulu, J. Dong, K. Hunter, K. Bettio, B. Vukusic, J. Ranisau, T. Tang, V. Sarhangian, Association between delayed discharge from acute care and rehabilitation outcomes and length-of-stay: a retrospective cohort study. Archives of Physical Medicine and Rehabilitation, 2022.
  9. J. Toor, I. Saleh, A. Abbas, J. Abouali, P. Wong, T. C. Y. Chan, V. Sarhangian, An anesthesia block room is financially net positive for a hospital performing arthroplasty. Journal of the American Academy of Orthopaedic Surgeons, 2022.
  10. M. Anderson, M. Bodur, S. Rathwell, V. Sarhangian, Optimization helps scheduling nursing staff at the long-term care homes of the city of Toronto. INFORMS Journal of Applied Analytics, 2023.
  11. B. Gorgulu, V. Sarhangian, A Newsvendor approach to design of surgical preference cards. Service Science, 2022.
  12. C. W. Chan, M. Huang, V. Sarhangian, Dynamic server assignment in multiclass queues with shifts, with applications to nurse staffing in emergency departments. Operations Research, 2021.
  13. J. Sismondo, V. Sarhangian, E. Borg, E. Roberge, F. H. Berger, Emergency imaging after a mass casualty incident: an operational perspective via a simulation study, Proceedings of the 2020 Winter Simulation Conference, 2021.
      • Best Contributed Applied Paper – Finalist
  14. V. Sarhangian, H. Abouee-Mehrizi, O. Baron, O. Berman, Threshold-based allocation policies for inventory management of red blood cells, Manufacturing & Service Operations Management, 2017.
  15. V. Sarhangian, H. Abouee‐Mehrizi, O. Baron, O. Berman, N. M. Heddle, R. Barty, Reducing the age of transfused red blood cells in hospitals: ordering and allocation policies, Vox sanguinis, 2016.
  16. V. Sarhangian, B. Balciog̃lu, A first passage time problem for spectrally positive Lévy processes and its application to a dynamic priority queue, Operations Research Letters, 2013.
  17. V. Sarhangian, B. Balciog̃lu, Waiting time analysis of multi-class queues with impatient customers, Probability in the Engineering and Informational Sciences, 2013.

Professional Activities

• Reviewer for journals: Operations Research, Management Science, Manufacturing & Service Operations Management, Stochastic Models, Decision Sciences, Production and Operations Management, Service Science, Naval Research Logistics, Healthcare Management Science, INFORMS Journal on Computing, Journal of the Operational Research Society.
• Professional Memberships: CORS, INFORMS, POMS