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Ayrıntılı Bilimsel Program ve Bildiri Özetleri - YAEM2010

Ayrıntılı Bilimsel Program ve Bildiri Özetleri - YAEM2010

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YAEM 2010<br />

YÖNEYLEM ARAÞTIRMASI VE ENDÜSTRÝ MÜHENDÝSLÝGI 30. ULUSAL KONGRESÝ<br />

Robust Reacti<strong>ve</strong> Scheduling of Intensi<strong>ve</strong> Care Units<br />

Erhan Kozan<br />

Mathematical Sciences, Queensland Uni<strong>ve</strong>rsity of Technology<br />

In this paper, methods for scheduling intensi<strong>ve</strong> care units (ICU) are<br />

explored. A general system is proposed that fits this situation and<br />

mo<strong>ve</strong> on to how this can be applied to the ongoing scheduling of ICU.<br />

Scheduling of patients in the ICU is complicated by the two general<br />

types; electi<strong>ve</strong> surgery and emergency arrivals. This complicated<br />

situation is handled by creating a tentati<strong>ve</strong> initial schedule and then<br />

reacting to uncertain arrivals as they occur. The model is then<br />

extended to a stochastic model which relaxes the assumption that<br />

emergency patients arri<strong>ve</strong> at known times. Because there is no<br />

efficient algorithm to sol<strong>ve</strong> it, heuristics techniques are de<strong>ve</strong>loped and<br />

examined. Schedules are generated using each, and compared to<br />

measures such as utilization, the proportion of time that the ICU is<br />

full, and the number of patients not admitted.<br />

Dispatching Policies for Doctors and Dimensioning in<br />

O<strong>ve</strong>rloaded Emergency Rooms<br />

1 2 2<br />

Tolga Tezcan , Vera Tilson , Greg Dobson<br />

1 Industrial and Enterprise Systems Engineering, Uni<strong>ve</strong>rsity of Illinois<br />

at Urbana-Champaign<br />

2 Simon GSB, Uni<strong>ve</strong>rsity of Rochester<br />

In this research we focus on a queuing model arising in emergency<br />

room operations. The model consists of three stations where the first<br />

and third stations are attended by a doctor and the second station is<br />

attended by nurses or technicians. Patients arri<strong>ve</strong> to the system<br />

endogenously and ha<strong>ve</strong> to be treated in stations 1, 2 and 3,<br />

consecuti<strong>ve</strong>ly, before they can lea<strong>ve</strong> the emergency room (ER). When<br />

the objecti<strong>ve</strong> is to maximize the steady state throughout and<br />

interruptions by the patients in the ER are ignored, we show that a<br />

push policy (the doctor gi<strong>ve</strong>s priority to station 1) is optimal in an<br />

o<strong>ve</strong>rloaded ER. When interruptions are considered we show that a pull<br />

policy (the doctor gi<strong>ve</strong>s priority to station 3) is asymptotically optimal<br />

in large o<strong>ve</strong>rloaded ER systems. Using these two results we propose<br />

closed form approximations for determining the appropriate number<br />

of beds needed in an ER.<br />

240

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