ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

Supply cost of crop residues for power plants was analysed. The supply chain includes five sub-processes, i.e. field collection, transportation, handling, pretreatment and storage. Five supply patterns were set up based on the differences in sub-processes, including bulk material pattern, centralized-storage chopping pattern, distributed-storage chopping pattern, baling pattern and pelleting pattern. The results show that, under specific conditions, the cost of the pelleting pattern is always the highest due to its high pelleting cost, followed by the baling pattern, the distributed-storage chopping pattern, and the centralized-storage chopping pattern in sequence. The bulk material pattern takes priority over the other three patterns when transportation distance is smaller than 69km, 28km and 16km respectively. The baling pattern needs improving since the cost reduction in transportation process can not effectively offset the cost increase in baling and handling processes. For all patterns except pelleting, purchase cost accounted for the largest proportion, followed by transportation cost and field collection cost.