I love to collaborate, and almost all of my research has involved graduate students and sometimes other researchers. With the caveat that these accomplishments are not solely mine, here are some highlights:
Mark Van Oyen’s education in stochastic modeling, control, and estimation and OR inspired him to develop methods to replace many static and inflexible operations with nearly optimal dynamically monitored and controlled operations. This vision has shaped his leadership in agile/flexible operations, next generation systems for healthcare, and monitoring and control of chronic diseases. Two seminal papers used dynamic “queueing control” as an alternative to traditional ad hoc approaches to polling systems: • [Q-CTRL-1] Heuristic scheduling of parallel heterogeneous queues with set-ups, Man Sci 1996 • [Q-CTRL-2] Stochastic scheduling of parallel queues with set-up costs, Queueing Sys 1995.
In seminal contributions to the science of operational flexibility, Van Oyen addressed labor flexibility (cross-training, economy of scope, and policies for worker coordination) and production lines, cellular manufacturing, plants, and supply chains.He generated the notions of Structural Flexibility (SF) and capability flexibility as predictive indices to guide the design of resilience in production. Among others, see • [FLEX-1] Agile workforce evaluation: a framework for cross-training and coordination, IIE Trans 2004 • [FLEX-2] Structural flexibility: A new perspective on the design of mfg. and service operations, Man Sci 2005 • [FLEX-3] Compensating for dynamic supply disruptions: Backup flexibility design, OR 2016.
With many collaborators, he created state of the art methods bridged operations to individual patient needs. He devised new solutions for many key areas of health system operations: Emergency Department (ED) redesign; “in-advance” appointment scheduling in multiple contexts; system-wide patient flow and operations eng.; clinical research units OM; coordinated care for surgery; online/self-serve appointment systems; ward/unit shift design plus assignment; design of skills-based nursing teams and staffing; and surgical case duration prediction, start time setting, and scheduling.
Surmounting the decades old barriers to network models of stochastic hospital patient flow, his 1st place award winning paper [HOSP] tractably modeled time-correlated patient flow itineraries through hospital and increased useable capacity while placing more patients in the proper bed unit. His emergency department (ED) “virtual streaming” paradigm based on new triage information may reduce waits by around 20%, and won the INFORMS Pierskalla Best Paper Award [EMRG-1]. His paper, [EMRG-2], on patient complexity assessment at triage cut adverse health outcomes 15%, winning Best Paper awards from MSOM journal for 2013-2015 and the 2016 MSOM Service Op’s S.I.G. Van Oyen is a world leader in advancing methods to achieve targets for the access delay from request date to the appointment date, with different target for each tier as indicated by urgency. In this nascent area, he generated four papers treating Clinical Research Units, integrated outpatient care, and coordinated surgical care. He advanced personalized medical decision making with the operational issues of the timing of office visits and diagnostic tests (monitoring) in addition to predicting disease progression [MDM-1]. This research won the 2012 Doing Good with Good OR 1st Prize and a 1st prize for POMS best healthcare OM paper. Stochastic control methods jointly optimizing medical control of risk factors and the timing of costly diagnostics in [MDM-2] were key to his student earning 2nd place in the INFORMS Dantzig dissertation competition. He developed the first contextual multi-armed bandit online learning method for joint personalized optimization of treatment/medication and the nested decision of the dosage for blood pressure control. [EMRG-1] Patient streaming as a mechanism for improving responsiveness in emergency departments, OR 2012 • [EMRG-2] Complexity-augmented triage: A tool for improving patient safety and operational efficiency, MSOM 2014 • [HOSP] Design and optimization methods for elective hospital admissions, OR 2014 • [MDM-1] Dynamic forecasting and control algorithms of glaucoma progression for clinician decision support, OR 2015 • [MDM-2] Dynamic monitoring and control of irreversible chronic diseases with application to glaucoma, POM 2019 •