A cantilever coordinate measuring machine(CCMM)is proposed according to the in-situ measurement requirement of workpieces with complex structures limited by the finite space of the5-axes computerized numerical control...A cantilever coordinate measuring machine(CCMM)is proposed according to the in-situ measurement requirement of workpieces with complex structures limited by the finite space of the5-axes computerized numerical control(CNC)processing site.Factors affecting uncertainty of measurement(UM)are classified and analyzed on the basis of uncertainty evaluation criteria,and the estimation technique of UM for measuring systems is presented.UM of the CCMM is estimated from the factors such as temperature,error motions as well as the mechanism deformations.Measurement results show that the actual measurement error is smaller than that of measurement requirement.展开更多
The low-cost,self-configuration capability and "plug-and-play" feature of Ethernet establishes its dominant position in the local area networks(LAN).However,it is hard to extend to large scale because of the...The low-cost,self-configuration capability and "plug-and-play" feature of Ethernet establishes its dominant position in the local area networks(LAN).However,it is hard to extend to large scale because of the legacy broadcast-based service discovery mechanism.Therefore,to solve this problem,a new split network architecture named Software-Defined Networking(SDN) is introduced in this paper,and a novel floodless service discovery mechanism(FSDM)for SDN is designed.For the FSDM,the widespread broadcast messages for Dynamic Host Configuration Protocol(DHCP) and Address Resolution Protocol(ARP) are considered especially,respectively.Then the DHCP relay and ARP proxy are proposed to handle DHCP broadcast messages and ARP broadcast messages,respectively.The proposed FSDM in this paper can eliminate flooding completely,reserve the autoconfiguration characteristics.Particularly,there is no need to change the existing hardware,software and protocols of hosts for the proposed scheme.Finally,the simulation results are demonstrated to show that our proposed model allows redundant links existed in network and has the property of scalability,which can significantly reduce network traffic in data plane and control traffic in control plane,and decrease the overhead of control plane.展开更多
The article describes design peculiarities of the novel compact vacuum circuit breaker with rated voltage 40.5 kV. The design incorporates several novel technical solutions： polycarbonate support insulation, mono-sta...The article describes design peculiarities of the novel compact vacuum circuit breaker with rated voltage 40.5 kV. The design incorporates several novel technical solutions： polycarbonate support insulation, mono-stable magnetic actuator, labyrinth pulling insulator, core-type flexible contact and new compact vacuum interrupter （VI）. Phases are encapsulated into silicone rubber providing required creepage distance and excellent tracking resistance. These novelties along with extensive modeling of the mechanical and electrical fields followed by design optimization resulted in weight reduction of more than 50% compared with alternatives available in the market. And this is in spite of built in sensors measuring： phase currents, zero-sequence current, phase voltages.展开更多
基金National Natural Science Foundation of China(No.51375338)
文摘A cantilever coordinate measuring machine(CCMM)is proposed according to the in-situ measurement requirement of workpieces with complex structures limited by the finite space of the5-axes computerized numerical control(CNC)processing site.Factors affecting uncertainty of measurement(UM)are classified and analyzed on the basis of uncertainty evaluation criteria,and the estimation technique of UM for measuring systems is presented.UM of the CCMM is estimated from the factors such as temperature,error motions as well as the mechanism deformations.Measurement results show that the actual measurement error is smaller than that of measurement requirement.
基金supported by the National Basic Research Program(973)of China(No.2012CB315801)the National Natural Science Fund(No.61302089,61300184)the fundamental research funds for the Central Universities(No.2013RC0113)
文摘The low-cost,self-configuration capability and "plug-and-play" feature of Ethernet establishes its dominant position in the local area networks(LAN).However,it is hard to extend to large scale because of the legacy broadcast-based service discovery mechanism.Therefore,to solve this problem,a new split network architecture named Software-Defined Networking(SDN) is introduced in this paper,and a novel floodless service discovery mechanism(FSDM)for SDN is designed.For the FSDM,the widespread broadcast messages for Dynamic Host Configuration Protocol(DHCP) and Address Resolution Protocol(ARP) are considered especially,respectively.Then the DHCP relay and ARP proxy are proposed to handle DHCP broadcast messages and ARP broadcast messages,respectively.The proposed FSDM in this paper can eliminate flooding completely,reserve the autoconfiguration characteristics.Particularly,there is no need to change the existing hardware,software and protocols of hosts for the proposed scheme.Finally,the simulation results are demonstrated to show that our proposed model allows redundant links existed in network and has the property of scalability,which can significantly reduce network traffic in data plane and control traffic in control plane,and decrease the overhead of control plane.
文摘The article describes design peculiarities of the novel compact vacuum circuit breaker with rated voltage 40.5 kV. The design incorporates several novel technical solutions： polycarbonate support insulation, mono-stable magnetic actuator, labyrinth pulling insulator, core-type flexible contact and new compact vacuum interrupter （VI）. Phases are encapsulated into silicone rubber providing required creepage distance and excellent tracking resistance. These novelties along with extensive modeling of the mechanical and electrical fields followed by design optimization resulted in weight reduction of more than 50% compared with alternatives available in the market. And this is in spite of built in sensors measuring： phase currents, zero-sequence current, phase voltages.
