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Table 4 Indexes, parameters, and variable sets

From: Managing daily surgery schedules in a teaching hospital: a mixed-integer optimization approach

Sets

S

Set of surgeries s to be scheduled in a surgical day

S k

Subset of surgeries (S) that can be performed by surgeon k

S r

Subset of surgeries (S) that can be performed in room r

R

Set of operating rooms r

K

Set of surgeons k

Parameters

TP s

Preparation time (preincision time) of the surgery s

TS sk

Surgery time (incision time) of the surgery s by surgeon k

TC s

Cleanup time (postincision time) of the surgery s

CV

Cost per minute of having an OR vacant

CW

Cost per minute of having the surgeon waiting

CO

Cost per minute of using an OR beyond the normal shift length T

T

Shift length

PT

Pause between surgeries done by the same surgeon

MOT

Maximum overtime

MaxS

Maximum number of surgeries performed by a surgeon

M

A large scalar value

Variables

x sr

Binary variable; 1 if surgery s S is done in room r R, 0 otherwise

y ss’k

Binary variable; 1 if sS precedes s'Sand is done by the same surgeon kK, 0 otherwise

z ss’kk’

Binary variable; 1 if s precede s'S and it is done by different surgeon k and k'K, 0 otherwise

q sk

Binary variable; 1 if surgery s S is done by surgeon k K, 0 otherwise

msR r

Non negative variable equal to the make span of room r R

msS k

Non negative variable equal to the make span of surgeon k K

ts s

Non negative variable equal to the start time of the surgery sS

tsS k

Non negative variable equal to the start time of the surgeon k K

vt

Non negative variable equal to the vacant time

ot r

Non negative variable equal to the overtime of room r R

wt k

Non negative variable equal to the waiting time of a surgeon k K

tc

Total cost