Objective One of major challenges in paleoenvironmental reconstruction using travertine in the Huanglong area is whether one can accurately determinate the age of travertine through high-precision and high-resolution...Objective One of major challenges in paleoenvironmental reconstruction using travertine in the Huanglong area is whether one can accurately determinate the age of travertine through high-precision and high-resolution dating techniques. Previous works of 14C or ESR chronology, however, have shown that the variation of deposition ages of travertine was displayed inconsistent with each other even conflict. For instance, (1) The oldest travertine age (80 ka) located in the middle of this travertine succession is departure from sequential deposition; (2) Top or boundary ages in this sedimentary section, even with the same dating method (14C), are three times errors, moreover, the age of the depositional sequence is not continuous. We report here the U230Th ages in lowest boundary of travertine in Dawanzhangjia Valley, Huanglong, China, to discuss the effectiveness of U-series dating for cold-water travertine and the significance of age for vicissitude of paleoenvironment.展开更多
针对内容中心网络(Content-centric Network,CCN)中现有的缓存替换策略考虑问题单一,直接删除替换内容的不足,提出一种基于通告转移机制(Notification Transfer Mechanism,NTM)的CCN网络缓存替换策略。结合动态内容流行度、缓存代价以...针对内容中心网络(Content-centric Network,CCN)中现有的缓存替换策略考虑问题单一,直接删除替换内容的不足,提出一种基于通告转移机制(Notification Transfer Mechanism,NTM)的CCN网络缓存替换策略。结合动态内容流行度、缓存代价以及时间因子求取内容缓存价值(Content Storage Value,CSV)。依据CSV值判定缓存替换内容,同时建立请求-响应的活动路径,替换内容沿活动路径存储在适合的节点,便于域内网络用户再次请求。仿真实验表明,相对于已有的几种缓存替换算法,该算法能够有效地提高CCN网络平均缓存命中率,降低路由平均请求跳数。展开更多
基金supported by National Natural Science Foundation of China (grants No. 41572035, 41472309, 41603041 and 41741026)the Open Funds of State Key Laboratory of Loess and Quaternary Geology (grant No. SKLLQG1620)
文摘Objective One of major challenges in paleoenvironmental reconstruction using travertine in the Huanglong area is whether one can accurately determinate the age of travertine through high-precision and high-resolution dating techniques. Previous works of 14C or ESR chronology, however, have shown that the variation of deposition ages of travertine was displayed inconsistent with each other even conflict. For instance, (1) The oldest travertine age (80 ka) located in the middle of this travertine succession is departure from sequential deposition; (2) Top or boundary ages in this sedimentary section, even with the same dating method (14C), are three times errors, moreover, the age of the depositional sequence is not continuous. We report here the U230Th ages in lowest boundary of travertine in Dawanzhangjia Valley, Huanglong, China, to discuss the effectiveness of U-series dating for cold-water travertine and the significance of age for vicissitude of paleoenvironment.