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Location Analysis In Transportation
Published in Dušan Teodorović, The Routledge Handbook of Transportation, 2015
Dušan Teodorović, Branka Dimitrijević, Milica Šelmić
In many cases, when locating facilities in networks, analysts try to cover as much as possible of the clients’ demand. “Coverage” of the node assumes the existence of a facility within a pre-specified coverage radius or service distance (Dp). Dp is the maximum distance that any client would have to travel to reach a facility. It defines the so-called catchment area. Airports, freight terminals, bus stops and other transportation facilities have corresponding catchment areas. If clients are located within a defined service distance (“covered”), they receive the service, otherwise they do not (Figure 27.1). The covering concept can be very useful in locating emergency services. Two major covering problems are the location set covering problem and the maximal covering problem.
Optimal junction localization minimizing maximum miners’ evacuation distance in underground mining network
Published in Mining Technology, 2023
Zhixuan Shao, Maximilien Meyrieux, Mustafa Kumral
The location problem focuses on the determination of one or more facilities serving a set of surrounding destinations as demand points in such a way as to optimize certain spatially dependent objectives (Brandeau and Chiu 1989). Such a problem could be classified in different ways based on specific criteria. As discussed in Farahani and Hekmatfar (2009), there could be (a) single or multi-facility problem based on the number of facilities, (b) continuous-space problem and discrete-space problem based on solution space settings, (c) deterministic and probabilistic problem based on demands, and (d) incapacitated and capacitated problems based on supply capacity. When the objectives and the applications are taken into consideration, the facility location problem could be categorized into the -median problem, covering problem, and -centre problem (Lotfian and Najafi 2019), where refers to the number of the facility to be located. The -median problem (a.k.a. MiniSum problem) is an NP-complete problem. It is to localize the desired facility (or facilities) in such a way as to minimize the total cost between the new facility (or facilities) and existing demand points. The covering problem focuses on finding a feasible location for the new facility (or facilities) such that all demand points are under coverage and the possible costs can be minimized. The -centre problem, also referred to as the MiniMax problem, attempts to localize the new facility (or facilities) surrounded by demand points under consideration such that the maximum distance between the demand points and the facility (or facilities) is minimized.