Efficient Shared Execution Processing of k-Nearest Neighbor Joins in Road Networks

Table 1

Symbols and their meanings.

Symbol	Definition
k	Number of requested NNs
	Outer object
	Inner object
	Vertex sequence where and are either an intersection vertex or a terminal vertex and the other vertices, , are intermediate vertices
	Outer segment generated from outer objects in the same vertex sequence
	Set of inner objects closest to outer object from
	Set of inner objects located in outer segment , that is,
	Length of the shortest path connecting two points and
	Length of the segment connecting two points and such that and are located in the same vertex sequence