Rotary bending fatigue tests were carried out for smooth specimens of a mediumcarbon steel with two different grain sizes near the fatigue limit. The process of fatigue damagewas observed by replication method, and th...Rotary bending fatigue tests were carried out for smooth specimens of a mediumcarbon steel with two different grain sizes near the fatigue limit. The process of fatigue damagewas observed by replication method, and the effects of grain size,stress level and microstructure on surface damage were studied. The effect of following cycle stress level on the coaxing effects was also discussed. The fatigue limit is the maximum stress at which the short fatigue crack initiates and becomes a non-propagating crack.. The length of non-propagating crack is related to grain sizes and stress level. The coaxing effects disappear when the following stress level is greater than the critical value.展开更多
设计了一种基于Homeplug AV技术利用家用同轴电缆实现家庭HFC网的双向接入设备。介绍了整个系统的设计思路,并对Homeplug AV over Coax设备进行了测试,包括衰减、设备组网、网络节点、传输帧的大小对整个系统的吞吐量、延时的影响,得出...设计了一种基于Homeplug AV技术利用家用同轴电缆实现家庭HFC网的双向接入设备。介绍了整个系统的设计思路,并对Homeplug AV over Coax设备进行了测试,包括衰减、设备组网、网络节点、传输帧的大小对整个系统的吞吐量、延时的影响,得出其性能要比电力线上用好得多,并对Homeplug AV over Coax的应用前景作了分析。展开更多
本文设计了一种利用家庭内部现有的传输介质(同轴电缆)、基于HomePlug AV技术实现家庭HFC网的双向接入的设备。文中介绍了从原理框图设计到整个系统的设计思路,并对HomePlug AV over Coax设备进行了测试,主要测试了衰减、设备组网、网...本文设计了一种利用家庭内部现有的传输介质(同轴电缆)、基于HomePlug AV技术实现家庭HFC网的双向接入的设备。文中介绍了从原理框图设计到整个系统的设计思路,并对HomePlug AV over Coax设备进行了测试,主要测试了衰减、设备组网、网络节点、传输帧的大小对整个系统的吞吐量、延时的影响,得出它的性能要比电力线上好得多。展开更多
To increase the limit of ethernet over coax （EoC） technology in the bidirectional reform of the hybrid fiber coaxial （HFC） network, an ethernet passive electronic network （EPEN） system based on Coax is proposed ...To increase the limit of ethernet over coax （EoC） technology in the bidirectional reform of the hybrid fiber coaxial （HFC） network, an ethernet passive electronic network （EPEN） system based on Coax is proposed and experimentally demonstrated in this paper. The proposed EPEN exploits the existing capabilities of the MAC layer in the ethernet passive optical network （EPON） for reduction of cost of the HFC network. As the MPCP （multi-point control protocol） is introduced in the EPEN, bandwidth control and higher efficiency can be achieved. The experimental results exhibit the throughput of system up to 100Mbps, which meet the requirements of HFC network. To improve the performance of EPEN, frequency division multiplexing （FDM） can be used for further increase of the throughput and more hardware processing modules in the future. can be implemented to enhance the capacity展开更多
文摘Rotary bending fatigue tests were carried out for smooth specimens of a mediumcarbon steel with two different grain sizes near the fatigue limit. The process of fatigue damagewas observed by replication method, and the effects of grain size,stress level and microstructure on surface damage were studied. The effect of following cycle stress level on the coaxing effects was also discussed. The fatigue limit is the maximum stress at which the short fatigue crack initiates and becomes a non-propagating crack.. The length of non-propagating crack is related to grain sizes and stress level. The coaxing effects disappear when the following stress level is greater than the critical value.
文摘设计了一种基于Homeplug AV技术利用家用同轴电缆实现家庭HFC网的双向接入设备。介绍了整个系统的设计思路,并对Homeplug AV over Coax设备进行了测试,包括衰减、设备组网、网络节点、传输帧的大小对整个系统的吞吐量、延时的影响,得出其性能要比电力线上用好得多,并对Homeplug AV over Coax的应用前景作了分析。
文摘本文设计了一种利用家庭内部现有的传输介质(同轴电缆)、基于HomePlug AV技术实现家庭HFC网的双向接入的设备。文中介绍了从原理框图设计到整个系统的设计思路,并对HomePlug AV over Coax设备进行了测试,主要测试了衰减、设备组网、网络节点、传输帧的大小对整个系统的吞吐量、延时的影响,得出它的性能要比电力线上好得多。
基金Supported by the National High Technology Research and Development Program of China(No.2007AA01Z229)
文摘To increase the limit of ethernet over coax （EoC） technology in the bidirectional reform of the hybrid fiber coaxial （HFC） network, an ethernet passive electronic network （EPEN） system based on Coax is proposed and experimentally demonstrated in this paper. The proposed EPEN exploits the existing capabilities of the MAC layer in the ethernet passive optical network （EPON） for reduction of cost of the HFC network. As the MPCP （multi-point control protocol） is introduced in the EPEN, bandwidth control and higher efficiency can be achieved. The experimental results exhibit the throughput of system up to 100Mbps, which meet the requirements of HFC network. To improve the performance of EPEN, frequency division multiplexing （FDM） can be used for further increase of the throughput and more hardware processing modules in the future. can be implemented to enhance the capacity
