近年来,在低轨(LEO)卫星星座通信网络中采用网际协议(IP)路由算法的研究已经取得了一系列进展,文章论述了LEO星座通信网络的特点、拓扑结构和虚拟节点策略。在此基础上提出了基于泛洪路由的LEO星座动态源路由算法DSR-LSN(Dynamic Source...近年来,在低轨(LEO)卫星星座通信网络中采用网际协议(IP)路由算法的研究已经取得了一系列进展,文章论述了LEO星座通信网络的特点、拓扑结构和虚拟节点策略。在此基础上提出了基于泛洪路由的LEO星座动态源路由算法DSR-LSN(Dynamic Source Routing algorithm in LEO Satellite Networks),星座网络仿真表明,DSR-LSN算法具有网络路由状态稳定性好、时延小的优点。展开更多
SQL SERVER 2005的备份/恢复功能表面上看似简单,但实际上其实现机制相当复杂并且微软公司并没有对外公布其备份/恢复机制的具体实现细节.包括专业数据库管理员在内很少有人能将SQL SERVER 2005的备份/恢复机制解释清楚,力图从一个较深...SQL SERVER 2005的备份/恢复功能表面上看似简单,但实际上其实现机制相当复杂并且微软公司并没有对外公布其备份/恢复机制的具体实现细节.包括专业数据库管理员在内很少有人能将SQL SERVER 2005的备份/恢复机制解释清楚,力图从一个较深入的层次研究分析SQL SERVER 2005的事务日志以及基于事务日志的备份与恢复.展开更多
The influence of the width of a lattice-matched A10.82In0.18N/GaN single quantum well (SQW) on the absorption coefficients and wavelength of the intersubband transition (ISBT) has been investigated by solving the ...The influence of the width of a lattice-matched A10.82In0.18N/GaN single quantum well (SQW) on the absorption coefficients and wavelength of the intersubband transition (ISBT) has been investigated by solving the Schr5dinger and Poisson equations self-consistently. The wavelength of 1-2 ISBT increases with L, the thickness of the single quantum well, ranging from 2.88 ~m to 3.59 ~.m. The absorption coefficients of 1-2 ISBT increase with L at first and then decrease with L, with a maximum when L is equal to 2.6 nm. The wavelength of 1-3 ISBT decreases with L at first and then increases with L, with a minimum when L is equal to 4 nm, ranging from approximately 2.03 p^m to near 2.11 p.m. The absorption coefficients of 1-3 ISBT decrease with L. The results indicate that mid-infrared can be realized by the A10.s2In0.1sN/GaN SQW. In addition, the wavelength and absorption coefficients of ISBT can be adjusted by changing the width of the SQW.展开更多
文摘近年来,在低轨(LEO)卫星星座通信网络中采用网际协议(IP)路由算法的研究已经取得了一系列进展,文章论述了LEO星座通信网络的特点、拓扑结构和虚拟节点策略。在此基础上提出了基于泛洪路由的LEO星座动态源路由算法DSR-LSN(Dynamic Source Routing algorithm in LEO Satellite Networks),星座网络仿真表明,DSR-LSN算法具有网络路由状态稳定性好、时延小的优点。
文摘SQL SERVER 2005的备份/恢复功能表面上看似简单,但实际上其实现机制相当复杂并且微软公司并没有对外公布其备份/恢复机制的具体实现细节.包括专业数据库管理员在内很少有人能将SQL SERVER 2005的备份/恢复机制解释清楚,力图从一个较深入的层次研究分析SQL SERVER 2005的事务日志以及基于事务日志的备份与恢复.
基金Project supported by the National High Technology Research and Development Program of China (Grant No.2007AA03Z403)the National Natural Science Foundation of China (Grant Nos.61076013 and 60776042)the National Basic Research Program of China (Grant No.2006CB921607)
文摘The influence of the width of a lattice-matched A10.82In0.18N/GaN single quantum well (SQW) on the absorption coefficients and wavelength of the intersubband transition (ISBT) has been investigated by solving the Schr5dinger and Poisson equations self-consistently. The wavelength of 1-2 ISBT increases with L, the thickness of the single quantum well, ranging from 2.88 ~m to 3.59 ~.m. The absorption coefficients of 1-2 ISBT increase with L at first and then decrease with L, with a maximum when L is equal to 2.6 nm. The wavelength of 1-3 ISBT decreases with L at first and then increases with L, with a minimum when L is equal to 4 nm, ranging from approximately 2.03 p^m to near 2.11 p.m. The absorption coefficients of 1-3 ISBT decrease with L. The results indicate that mid-infrared can be realized by the A10.s2In0.1sN/GaN SQW. In addition, the wavelength and absorption coefficients of ISBT can be adjusted by changing the width of the SQW.