西辽河平原区地下水埋深变化趋势与超采分析     

严聆嘉  何鑫  陆垂裕  刘建祥  马飞华  李泽鹏 《水文》2021,41(6)

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地理国情与基础地理信息数据同步更新外业调绘系统的构建     

何鑫  应国伟  高倩影  李亮 《测绘通报》2017,(9):116-119

利用全新的外业数据调绘理念,在地图数据缓存切片技术、GPS定位技术及手持移动终端等技术设备基础上构建了地理国情与基础地理信息数据同步更新外业调绘系统,实现野外作业时,同一地物要素只需补测一次即可完成地理国情与基础地理信息数据的外业调绘工作,避免了重复外业采集生产,有利于降低地理国情与基础地理信息数据的更新成本。  相似文献   

八角形FPSO与穿梭油轮串靠外输中碰撞风险分析          下载免费PDF全文

唐友刚  肖泥土  陈勃任  何鑫  王泳辉 《海洋工程》2017,35(2):7-12

针对300 m作业水深下的八角形FPSO,提出采用穿梭油轮串靠的外输作业方案,研究外输过程中穿梭油轮与FPSO之间由于过分纵荡运动而引起的碰撞风险发生概率。建立由八角形FPSO及其系泊系统、穿梭油轮、系泊大缆等组成的浮式多体系统分析模型,在外输海况条件下,得到穿梭油轮与FPSO间距的时历曲线,结合极值理论,对过分纵荡运动进行预报,进而对外输系统的碰撞风险进行分析;揭示海流的方向变化对于外输系统碰撞风险的影响规律。  相似文献   

Relationship between trawl selectivity and fish body size in a simulated population     

孙鹏  梁振林  黄六一  唐衍力  何鑫 《中国海洋湖沼学报》2013,31(2):327-333

Trawl is a main fishing gear in Chinese fishery,capturing large fish and letting small ones at large.However,long-term use of trawl would result in changes of phenotypic traits of the fish stocks,such as smaller size-at-age and earlier age-at-maturation.In this study,we simulated a fish population with size characteristics of trawl fishing and the population produces one generation of offspring and lives for one year,used trawl to exploit the simulated fish population,and captured individuals by body size.We evaluated the impact of the changes on selectivity parameters,such as selective range and the length at 50% retention.Under fishing pressure,we specified the selectivity parameters,and determined that smaller selection rates and greater length at 50% retention were associated with an increased tendency towards miniaturization.  相似文献