Vehicle Routing Problem in Relief Supply under a Crisis Condition considering Blood Types

Table 2

Detail of the proposed model.

Assumption
(i) The start time of the blood donation operations is 8:00, and the end time is at most 20:00.
(ii) The stop time has a constraint with a minimum and maximum limit.
(iii) The collected blood in each BS depends on the city population and the stop time in that station.
(iv) There is a specific demand for blood that should be satisfied; the shortage is not allowed. Therefore, it is a vital constraint.
(v) Each equipped bus and the helicopter start their operations from the crisis-stricken city; after visiting various areas, it returns to the crisis-stricken city. The number of equipped buses is limited and specified.
Parameters
Notation	Description
	Maximum number of points chosen as the station
	The number of bloodmobiles (buses)
	The donors’ population
	The blood type percentage in that population (the normality of universal blood type)
	The demand of blood types
	The interval (time) that a bus travels from city to city
	The interval (time) a helicopter travels from city to city
	The population of donors frequently donating blood
Binary variable
Nonnegative variable
Notation	Description
	The required time for arriving city
	The stop time (hours) of bus at city
	The stop time (hours) of the helicopter at city
	The amount of collected blood of blood types by bloodmobiles (buses)
	The amount of collected blood of blood types by the helicopter
	The total amount of collected blood by the bloodmobiles (buses) and the helicopter per blood type
	Function of the amount of collected blood type b by bus k at city , when it stopped hours