could be coupled with one indication, the chances
for the patient to find one treatment are larger. We
suggest a method to classify them in a specific order,
which facilitates the patient to find a center.
Definition: Priority group The couple IP is char-
acterized by a priority group, combination of the medical
benefit and the proof of the innovative therapy.
The priority group defines a mutable order for
treatments. The patient initially starts the research of
centers with its best priority group.
We suggest a final date for patient, obliging him
to find a center for a treatment before. It allows the
patient to ask centers for a treatment multiple times if
he is not accepted immediately. We introduce in this
way the multi-demand of the patient to centers. So
the final date for the treatment depends on the genera-
tor, which acts at the beginning of every time step. Its
discussions with the recruitment model create the pa-
tients in an environment of competition of radiother-
apy centers. This is an institutional agent operating
with biological agents.
3 THE PROCESS OF RESEARCH
OF CENTERS
The process of research of centers is based on tech-
nical requirements of the disease of the patient, his
general healthy state, his preferences to the existing
offer and geographical position of centers.
3.1 Description of the Center
The choice of the patient is influenced by possible
treatments, available facilities in centers, their geo-
graphic position and their medical politics.
1. The Mechanism of Medical Politics
Definition: Medical Politics represents preferences
of a center to the accepted indications. When it exists, it
gives priority of some treatments and/or eliminates others,
composed by several rules being a part of the planning.
Definition: Reserved Time represents reserved slots
in the hospital planning for a number of patients described,
by special characteristics as an indication and a protocol.
We suggest some rules for medical politics, de-
fined as independent structures and not essential for
the functioning of the center, as well as the existence
of the mechanism of medical politics.
- A Reserved Time for a Couple of IP. The center
constitutes a group of couples, composed by reserved
slots for IP treatments. This way the center gives pri-
ority to treatments with a better therapeutic gain.
- A List of Priorities, with reserved slots for one
or multiple priority groups. The last two rules could
introduce a conflict situation. If the priority group and
the couple of the same IP have reserved time, the med-
ical knowledge gives priority to the rule of the couple.
- limit the Usage of Particles such as Carbone, for
hadrontherapy centers. We estimate the annual use of
the particle and control it to not exceed a fixed limit.
2. The Scheduling Model
The scheduling model is a simple model, which plans
treatments and calculates the probability of accep-
tance of one patient according to its time of waiting.
We estimate the probability of acceptance with a mo-
bile mean computed for each IP accepted in a center.
A response is then given to the patient.
We constructed the SM in order to be able to test
the RM. The number of treated patients is maximized
regarding medical politics. We used linear program-
ming in 0, 1 to implement it. Constraints are not listed
here, but we illustrate the use of the model on the Fig.
3. The SM is used whenever the recruitment model
needs to have a response for one patient. It also plans
treatments for patients already in the waiting queue
and when it is not possible, the patient stays in the
waiting queue considering his preferences. The SM is
used for planning treatments for each room and dur-
ing the whole simulation, we use the RLE encoding
(RLE, 2010). It matches each day with the planning
of a room. When the scheduling model doesn’t find
a place for one patient, not corresponding to medical
politics, he is rejected directly and he has to search
for another center. As depicted on Fig. 3 there are
some rules to use during the discussion between the
SM and the agent of the center. We can identify them
in the same way as it has been done in (Wagner, 2003;
Taveter and Wagner, 2001).
Planing of the Centr
e
updates
Waiting queue
scheduling model
according to
the capacity of
the centre
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Day
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Day
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time
rooms
external pool of patients
patients with
treatment
patients staying
in the waiting
queue
rejected
patients
1
3
2
4
5
Figure 3: Interaction between the SM and the RM. We make
updates during the planning of treatments, in consequence
coming patients are evaluated and accepted or rejected.
3. The Waiting Queue
The waiting queue is a consequence of the mechanism
of medical politics. When a patient being a part from
medical politics arrives with a demand, and no place
is available for him, than if he could ”wait” according
to his final date of treatment, he goes in an waiting
queue if he agrees. The situation of this patient is
evaluated at every time step (Fig. 4). Moreover the
entry of new patients could force the exit of a patient.
A special way of ordering is applied to the waiting
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