A Study on Online Scheduling Problem of Integrated Order Picking and Delivery with Multizone Vehicle Routing Method for Online-to-Offline Supermarket

Table 3

The five-field notation.

	Picker configuration (we regard “picker” as “machine” in this field); : orders are processed by m identical pickers.
	Restrictions and constraints on order parameters; Online: orders arrive dynamically.; : orders are processed by batches and the capacity of the batch is no more than .
	Vehicle configuration.; : unlimited vehicles available and each vehicle can service at most customers.; Routing: batch delivery with routing method, i.e., orders going to different customers can be delivered together in the same route (where vehicle routing is a part of the decision).
	Number of customers; : the delivery area is separated into zones.
	Objective function; ,: the weights of the time-dependent function and cost-dependent function, respectively, where ,.; : the time-dependent function, that is, the maximum delivery completion time of all orders.; TC: the cost-dependent function, that is, the total delivery cost, i.e., the sum of the fixed delivery cost (FC) and variable delivery cost (VC), where and .