转子断条是笼型异步电动机常见的一种故障 ,采用快速傅立叶变换对定子电流进行频谱分析是目前应用最广泛的转子断条在线检测方法 ,但其缺点为灵敏度低。作者采用的可变步长 L MS ( VSS)算法可以有效地解决传统自适应算法存在的收敛速度...转子断条是笼型异步电动机常见的一种故障 ,采用快速傅立叶变换对定子电流进行频谱分析是目前应用最广泛的转子断条在线检测方法 ,但其缺点为灵敏度低。作者采用的可变步长 L MS ( VSS)算法可以有效地解决传统自适应算法存在的收敛速度与收敛误差之间的矛盾 ,可以显著地改善对干扰的抑制 ,提高检测转子断条故障的灵敏度。展开更多
This paper proposes a novel session setup mechanism in IMS(IP Multimedia Subsystem) by introducing the functional entity termed VSS(Visitor Subscriber Server) which is used to provide registration and location managem...This paper proposes a novel session setup mechanism in IMS(IP Multimedia Subsystem) by introducing the functional entity termed VSS(Visitor Subscriber Server) which is used to provide registration and location management.The new mechanism aims at improving session setup procedure by a betterment of location management in IMS.Through the use of two-tier subscriber information database constituted by the HSS(Home Subscriber Server) and the VSS, the new mechanism seperates the registration procedure and location management from the S-CSCF(Serving-Call'Session Control Function), and makes them be handled by the VSS.At the same time, the new mechanism updates the signaling procedure of registration and session setup.With VSS based location management, the cost of registeration and session setup procedure as well as the delay of session setup procedure become lower.The cost and delay functions of the new session setup mechanism as well as the cost function of new registeration are deduced.Then, simulations and analysis verify that the performance of this new mechanism gets the benefit in cost and time.展开更多
文摘转子断条是笼型异步电动机常见的一种故障 ,采用快速傅立叶变换对定子电流进行频谱分析是目前应用最广泛的转子断条在线检测方法 ,但其缺点为灵敏度低。作者采用的可变步长 L MS ( VSS)算法可以有效地解决传统自适应算法存在的收敛速度与收敛误差之间的矛盾 ,可以显著地改善对干扰的抑制 ,提高检测转子断条故障的灵敏度。
基金National Science Fund for Distin-guished Young Scholars (No. 60525110)National 973 Program (No. 2007CB307100, 2007CB307103)+1 种基金Program for New Century Excellent Talents in University (No.NCET-04-0111)Development Fund Project for Electronic and Information Industry (Mobile Service and Application System Based on 3G)
文摘This paper proposes a novel session setup mechanism in IMS(IP Multimedia Subsystem) by introducing the functional entity termed VSS(Visitor Subscriber Server) which is used to provide registration and location management.The new mechanism aims at improving session setup procedure by a betterment of location management in IMS.Through the use of two-tier subscriber information database constituted by the HSS(Home Subscriber Server) and the VSS, the new mechanism seperates the registration procedure and location management from the S-CSCF(Serving-Call'Session Control Function), and makes them be handled by the VSS.At the same time, the new mechanism updates the signaling procedure of registration and session setup.With VSS based location management, the cost of registeration and session setup procedure as well as the delay of session setup procedure become lower.The cost and delay functions of the new session setup mechanism as well as the cost function of new registeration are deduced.Then, simulations and analysis verify that the performance of this new mechanism gets the benefit in cost and time.
