基于用户体验的4G端到端业务与网络质量测试工具

中国移动自主研发了基于用户体验的端到端业务与网络质量评测工具,实现端到端业务质量和性能评测,实现现网真实"用户感知"的可测、可量、可知.基于用户体验的4G端到端业务与网络质量测试工具是面向业务质量和移动互联网网络测试的专业工具,支持Android、iOS操作系统,贴近用户的真实使用场景,实现真正以"用户"为中心的端到端业务质量评测,具备基础通信、网络性能、用户体验、终端性能等测试能力,能够从用户的角度反映实际业务和网络的运行情况、性能质量.该工具多个版本全面支撑了中国移动全网4G试商用城市验收测试、4G全网常态化端到端服务监测,填补了业内自有用户体验评测工具的空白,受到多方好评.     

Toward broad optimal output bandwidth dielectric elastomer actuators

Science China Technological Sciences - Dielectric elastomer actuators (DEAs) are one of the most promising soft actuation technologies owing to their relatively high power density and...     

Dynamic variations of the outer radiation belt during magnetic storms for 1.5–6.0 MeV electrons

The CME’s structure of solar wind (interplanetary magnetic field) is different from CIR’s. The two processes in which plasma and solar wind energy are injected into the Earth’s inner magnetosphere are not the same. So, the variations of energetic electrons flux in the radiation belts are different between the storms associated with CMEs and CIRs. By using data from SAMPEX (Solar, Anomalous, and Magnetospheric Particle Explorer) satellite, we have investigated the dynamic variations of the outer radiation belt for 1.5–6.0 MeV electrons during 54 CME-driven storms and 26 CIR-driven recurrent storms. According to the superposed epoch analysis, for CME- and CIR-driven storms, when the Dst index reaches the minimum, the locations of the outer boundary move to L=4 and L=5.5, respectively. In the recovery phases, the locations of the outer boundary of the outer radiation belt are generally lower than and slightly higher than those before CME- and CIR-driven storms, respectively. We have found that the logarithmically decaying 1/e cut-off L-shell is a satisfying indicator of the outer boundary of the outer radiation belt. Furthermore, our study shows that the logarithmically decaying 1/e cut-off latitude is dependent on the Kp index in the main phases of CME- and CIR- driven storms, while in the recovery phases, there is no obvious correlation. In addition, it has been shown that the locations of the peak electron flux are controlled by the minimum Dst index in the main phases of CME-driven storms. The influences of multiple storms on the electron flux of outer radiation belt have also been investigated.