Tomography reconstruction algorithm is one of the key components of positron emission tomography (PET) scanners,most PET scanners use statistical iterative reco
1.清选。用水冲洗玉米联合收割机及秸秆还田装置的内外泥土,清理碎玉米秸秆、缠草等杂物。卸下的链条、螺丝及甩锤(刀)用柴油浸泡洗净油泥,用机油浸泡5～10min,后涂上润滑脂用
An exact average symbol error rate analysis for the distributed dual-hop relay cooperative network with multiple relays in a Nakagami-m fading environment is pr
水稻机插硬地育苗,是利用水泥场地或土场地代替传统田间育秧,培育符合机插的壮秧,秧苗要求秧龄18～20天,苗高15～17cm,叶龄3.5～4.0叶,达到苗挺、叶绿、生长整齐和秧苗提起时不断裂
急诊医学是一门新兴的跨专业综合学科,其技术特征与发展无固定模式.如何适应独立完成涉及多专科的危重病人诊治、抢救任务,结合自身医院特点找到切合实际的临床路径,进一步探
1.间苗大豆出苗后,在全苗的基础上及早间苗,是一项行之有效的增产措施。其增产效果主要取决于间苗时间的早晚,一般在两片对生单叶展开时就要抓紧进行。据各地对比试验,间苗比
The existing research of welding arc mainly focuses on the stable combustion state and the research on the mechanism of welding arc ignition process is quite la
莱恩LION-65A型半喂入联合收割机，是以柴油机为发动机的半喂入谷物收获机械。主要特点：采用江铃JX493型柴油机作动力装置，功率储备大、动力性能稳定、油耗小、排放优良；采用工况
The existing investigations on piezoelectric materials containing an elliptic hole or a crack mainly focus on remote uniform tensile loads.In order to have a be
南宋文人刘震孙人品正直,为官仁慈,交游甚广,创作颇为活跃,然事迹湮没不彰,迄无考订。今勾稽史料、方志、文集等资料,考述其生平行事,知其字长卿(或称长翁),号朔斋;郡望渤海,