Globally, traditional power systems are rapidly transforming towards the adoption of smart grid platforms. Substations which are at the center of the electric power transformation from the power plant are changing to ...Globally, traditional power systems are rapidly transforming towards the adoption of smart grid platforms. Substations which are at the center of the electric power transformation from the power plant are changing to IEC 61850 based digital substations. Therefore, within substation, there is a growing demand for the IEC 61850 based Intelligent Electronic Devices (IEDs). The operation of multiple manufacturers of IEDs in a single digital substation network increases the need for IEC 61850 communications specification conformance diagnosis to ensure interoperability for efficient data exchange between IEDs. The IEC 61850-10 presents test items for diagnosing communication specification conformance. There are many test tools available in the market today to test the compliance of the IEC 61850 communications specifications to the IED. In this paper, we propose a model-based diagnostic method for IED communication conformance testing. The proposed model-based software therefore uses the “drag and drop” technique to select the various IEC 61850 communication services (objects) required to design the test case in a user friendly Graphical User Interface (GUI). This makes the service conformance testing more flexible for test engineers and system integrators especially in situations that require test case modifications. Also, the proposed software tool makes it easy to understand the various IEC 61850 services using the friendly GUI.展开更多
A Macovo queuing network (MQN) based model of a general client/server system with multitype serversand with consideration of the transfer time of the computer network is proposed. The MQN was solved by analyzinga gene...A Macovo queuing network (MQN) based model of a general client/server system with multitype serversand with consideration of the transfer time of the computer network is proposed. The MQN was solved by analyzinga general open MQN with limited clients. In addition, the steady-state probability distribution theorem was proven.Thus, analytical load indices such as queue length at the servers and the server efficiency were obtained. Moreover,the sufficient and necessary conditions for server load balance were found. Finally, a client/server system was analyzed to illustrate the procedure for computing system load indices. The results are not only helpful for analyzing bottlenecks in the client/server system, but are also fundamental to static system configuration design.展开更多
计算机网络和终端技术的进步推动了计算机应用的迅速发展,用户可以通过网络获得各种不同的分布式应用.但是,这些应用系统都依赖于固定操作系统,如W indow s、L inux等.本文提出了一种支持终端通过以太网从服务器动态获得不同操作系统、...计算机网络和终端技术的进步推动了计算机应用的迅速发展,用户可以通过网络获得各种不同的分布式应用.但是,这些应用系统都依赖于固定操作系统,如W indow s、L inux等.本文提出了一种支持终端通过以太网从服务器动态获得不同操作系统、并在客户端动态执行的远程启动协议M RBP 2(M u lti-O S R em ote Booting P rotoco lTw o).M RBP 2协议把服务器上的不同操作系统通过O SPM机制(O perating System P rebootM echan ism)和SFTP协议(Sector based F ile T ransfer P rotoco l)下载到客户端,完成操作系统的启动和运行.本文还给出M RBP 2协议的实现及在实际系统上的应用.展开更多
文摘Globally, traditional power systems are rapidly transforming towards the adoption of smart grid platforms. Substations which are at the center of the electric power transformation from the power plant are changing to IEC 61850 based digital substations. Therefore, within substation, there is a growing demand for the IEC 61850 based Intelligent Electronic Devices (IEDs). The operation of multiple manufacturers of IEDs in a single digital substation network increases the need for IEC 61850 communications specification conformance diagnosis to ensure interoperability for efficient data exchange between IEDs. The IEC 61850-10 presents test items for diagnosing communication specification conformance. There are many test tools available in the market today to test the compliance of the IEC 61850 communications specifications to the IED. In this paper, we propose a model-based diagnostic method for IED communication conformance testing. The proposed model-based software therefore uses the “drag and drop” technique to select the various IEC 61850 communication services (objects) required to design the test case in a user friendly Graphical User Interface (GUI). This makes the service conformance testing more flexible for test engineers and system integrators especially in situations that require test case modifications. Also, the proposed software tool makes it easy to understand the various IEC 61850 services using the friendly GUI.
文摘A Macovo queuing network (MQN) based model of a general client/server system with multitype serversand with consideration of the transfer time of the computer network is proposed. The MQN was solved by analyzinga general open MQN with limited clients. In addition, the steady-state probability distribution theorem was proven.Thus, analytical load indices such as queue length at the servers and the server efficiency were obtained. Moreover,the sufficient and necessary conditions for server load balance were found. Finally, a client/server system was analyzed to illustrate the procedure for computing system load indices. The results are not only helpful for analyzing bottlenecks in the client/server system, but are also fundamental to static system configuration design.
文摘计算机网络和终端技术的进步推动了计算机应用的迅速发展,用户可以通过网络获得各种不同的分布式应用.但是,这些应用系统都依赖于固定操作系统,如W indow s、L inux等.本文提出了一种支持终端通过以太网从服务器动态获得不同操作系统、并在客户端动态执行的远程启动协议M RBP 2(M u lti-O S R em ote Booting P rotoco lTw o).M RBP 2协议把服务器上的不同操作系统通过O SPM机制(O perating System P rebootM echan ism)和SFTP协议(Sector based F ile T ransfer P rotoco l)下载到客户端,完成操作系统的启动和运行.本文还给出M RBP 2协议的实现及在实际系统上的应用.
