Ni	The node i
IDr	The ID of requester
IDw	The ID of worker
IDre	The ID of report
IDt	The ID of transaction
Ti	The i-th transaction
Bi	The i-th block
REi	The i-th report
Ri	The i-th requester
Wi	The i-th worker
Mi	The i-th miner
Uw	A set of workers
Pent	Blockchain pending list
Tre	The time stamp of report
PEYr	The payment for each requester
PEYw	The payment for each worker
PEYm	The payment for mining each block
CoREi	The content of the i-th report
CoTk	The content of the k-th transaction
LRi	The location of the i-th requester
LREi	The location of the i-th report
LWi	The location of the i-th worker
Lati,p	The latitude of the i-th node with role p
Loni,p	The longitude of i-th node with role p
TREi	The type of the i-th report
θ	The central angle between two points on a sphere