The Doctor Rostering Problem - Asser Fahrenholz
The Doctor Rostering Problem - Asser Fahrenholz
The Doctor Rostering Problem - Asser Fahrenholz
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Chapter 2. <strong>The</strong> <strong>Doctor</strong> <strong>Rostering</strong> <strong>Problem</strong> 5<br />
<strong>Doctor</strong> 1 2 3 4 5 6<br />
Week 1 Tuesday NDO Wednesday Thursday Friday Monday<br />
Week 2 NDO Wednesday Thursday Friday Monday Tuesday<br />
Week 3 Wednesday Thursday Friday Monday Tuesday NDO<br />
Week 4 Thursdag Friday Monday Tirsdag NDO Wednesday<br />
Week 5 Friday Monday Tirsdag NDO Wednesday Thursdag<br />
Week 6 Monday Tirsdag NDO Wednesday Thursdag Friday<br />
Table 2.1: Rolling days off, NDO: no day off<br />
2.2 Rolling Days Off<br />
A specific requirement of this project is rolling days off (RDO). <strong>The</strong>se define which<br />
weeks a doctor gets a day off and which weeks contains no day off (NDO) for each<br />
doctor. Table 2.1 illustrates the concept of rolling days off.<br />
A key point of RDO is the fact that all doctors receive weekends where they have both<br />
the predating Friday and the postdating Monday off.<br />
<strong>The</strong> RDO as a constraint is omitted from the mathematical model of this problem and<br />
is instead implemented as a program mechanism.<br />
2.3 Literature review<br />
Previous work on the nurse scheduling problem (NSP) has been covered by many ap-<br />
proaches, taking different angles and perspectives throughout the problem environment.<br />
In this section, I briefly review articles that has served as inspiration to this project.<br />
Nonobe and Ibaraki [18] applies a general weighted constraint satisfaction problem<br />
(WCSP) solver, using a Tabu Search (TS), to a range of problems, incl. the NSP.<br />
Also applying a weight control mechanism to each iteration of TS works well for them.<br />
<strong>The</strong>y choose to handle hard and soft constraints on the same level of processing.<br />
Dias et al. [7] deals with a relatively large problem. <strong>The</strong>y apply both a Genetic Algorithm<br />
(GA) heuristic and a TS for solving a problem with over 1500 nurses, 30 supervisory<br />
nurses and 30 wards and finds that the two heuristics performs equally well, with one<br />
more time efficient and slightly worse results than the other and vice versa.<br />
In Bard and Purnomo [2] the authors discuss the issue of sudden shortages appearing due<br />
to the fluctuation in patients needing health care. <strong>The</strong> problems handled are relatively<br />
large, scheduling more than 120 nurses.