The damper is capable of providing a continuously variable dampering force/torque in response to a magnetic field. It consists of an upside cap and an underside cap with a rotor located between them, the magneto-rheol...The damper is capable of providing a continuously variable dampering force/torque in response to a magnetic field. It consists of an upside cap and an underside cap with a rotor located between them, the magneto-rheological (MR) fluid is filled into the gaps between the rotor and the caps. When the viscosity of the MR fluid increases under the influence of the magnetic field, the movement of the rotor will be resisted. The output torque is made up of the torque caused by the magnetic field, the torque caused by the plastic viscosity of the MR fluid, and the torque caused by the coulomb friction. The viscous torque can be calculated by a simple method and the frictional torque can be obtained by experiments. The torque dependent on the magnetic field is obtained by electromagnetic finite dement analysis. Experiments are done on the damper prototype and the validity of the design is verified.展开更多
In this paper,the sensors array technique is applied to the quality detection of aluminum alloy spot welding.The sensors array has three forms,i.e.,linear magnetic sensors array,annular magnetic sensors array and cros...In this paper,the sensors array technique is applied to the quality detection of aluminum alloy spot welding.The sensors array has three forms,i.e.,linear magnetic sensors array,annular magnetic sensors array and cross magnetic sensors array.An algorithm based on principal component analysis is proposed to extract the signal eigenvalues.The three types of magnetic sensors array are used in the experiment of monitoring the signal.After the eigenvalues are extracted,they are used to build a relationship with ...展开更多
Broadband PLC (power line communication) technology is a main factor of the development of digital convergence in the indoor network. It uses the already existing power cable infrastructure for communication purpose...Broadband PLC (power line communication) technology is a main factor of the development of digital convergence in the indoor network. It uses the already existing power cable infrastructure for communication purposes. The EM (electromagnetic) field radiating from the cable could, however, disturb other communication systems, and thus should be evaluated. The MoM (method of moment) and the FEM (finite element method) have been studied to estimate the EVI field emitted from the power cable. However, the M oM is difficult to treat the dielectric material of the cable and the FEM is time consuming. This paperpresents a new approach to estimate the radiated EM fields caused by PLC sy stems from the CM current along the cable, based on the transmission line theory. The proposed model has the advantage of using the measured primary parameters of the cable. An experimental analysis of the EM radiation distribution is also presented. A comparison showed that the model results agree quite well with the measurements performed in this study.展开更多
基金The National Basic Research Program of China(973Program) (No2002CB312102)the National Natural ScienceFoundation of China (No60675047)
文摘The damper is capable of providing a continuously variable dampering force/torque in response to a magnetic field. It consists of an upside cap and an underside cap with a rotor located between them, the magneto-rheological (MR) fluid is filled into the gaps between the rotor and the caps. When the viscosity of the MR fluid increases under the influence of the magnetic field, the movement of the rotor will be resisted. The output torque is made up of the torque caused by the magnetic field, the torque caused by the plastic viscosity of the MR fluid, and the torque caused by the coulomb friction. The viscous torque can be calculated by a simple method and the frictional torque can be obtained by experiments. The torque dependent on the magnetic field is obtained by electromagnetic finite dement analysis. Experiments are done on the damper prototype and the validity of the design is verified.
基金Supported by National High Technology Research and Development Program ("863" Program) of China (No.2008AA04Z136)National Natural Science Foundation of China(No.50975197)+1 种基金Cooperation Project in Industry,Education and Research of Guangdong Province and Ministry of Education of China(No.2007A090302105)Tianjin Research Program of Application and Advanced Technology (No.09JCZDJC24000)
文摘In this paper,the sensors array technique is applied to the quality detection of aluminum alloy spot welding.The sensors array has three forms,i.e.,linear magnetic sensors array,annular magnetic sensors array and cross magnetic sensors array.An algorithm based on principal component analysis is proposed to extract the signal eigenvalues.The three types of magnetic sensors array are used in the experiment of monitoring the signal.After the eigenvalues are extracted,they are used to build a relationship with ...
文摘Broadband PLC (power line communication) technology is a main factor of the development of digital convergence in the indoor network. It uses the already existing power cable infrastructure for communication purposes. The EM (electromagnetic) field radiating from the cable could, however, disturb other communication systems, and thus should be evaluated. The MoM (method of moment) and the FEM (finite element method) have been studied to estimate the EVI field emitted from the power cable. However, the M oM is difficult to treat the dielectric material of the cable and the FEM is time consuming. This paperpresents a new approach to estimate the radiated EM fields caused by PLC sy stems from the CM current along the cable, based on the transmission line theory. The proposed model has the advantage of using the measured primary parameters of the cable. An experimental analysis of the EM radiation distribution is also presented. A comparison showed that the model results agree quite well with the measurements performed in this study.