In view of problems of long end-to-end time and high packet loss rate of positioning wireless sensor network (PWSN) on coal mining face. a guaranteed greedy scheduling (GGS) algorithm was proposed to optimize network transmission performance. The GGS algorithm combines the particle swarm optimization (PSO) algorithm and the greedy algorithm. The PSO algorithm is used to orderly proces... https://herbsdailyes.shop/product-category/childrens-vitamins/