Based on the wave radiation and diffraction theory, this paper investigates a new type breakwater with upper arcshaped plate by using the boundary element method(BEM). By comparing with other three designs of plate ty...Based on the wave radiation and diffraction theory, this paper investigates a new type breakwater with upper arcshaped plate by using the boundary element method(BEM). By comparing with other three designs of plate type breakwater(lower arc-shaped plate, single horizontal plate and double horizontal plate), this new type breakwater has been proved more effective. The wave exiting force, transmission and reflection coefficients are analyzed and discussed. In order to reveal the wave elimination mechanism of this type of breakwater, the velocity field around the breakwater is obtained. It is shown that:(1) The sway exciting force is minimal.(2) When the ratio of the submergence and wave amplitude is 0.05, the wave elimination effect will increase by 50% compared with other three types of breakwater.(3) The obvious backflow is found above the plate in the velocity field analysis.展开更多
Pressure guide plate plays a certain role in the safe operation of elevator.Based on understanding the respective performance of new and old pressure guide plates,this paper analyses the problems existing in the origi...Pressure guide plate plays a certain role in the safe operation of elevator.Based on understanding the respective performance of new and old pressure guide plates,this paper analyses the problems existing in the original pressure guide plate.It also conducts stress analysis according to the function of pressure guide plate on elevator,and designs a new type of pressure guide plate combined with technological capability and equipment.According to the stress characteristics,a test device is designed and a comparative test is made between the new type of pressure guide plate and the old in order to test the reliability of the new type of pressure guide plate.The test proves that the new pressure guide plate of elevator can meet the requirements of product use and safe operation of elevator products.展开更多
Since copper has excellent properties such as malleability and conductivity,it is widely used in the electronics field.Copper sulfate plating is expanding further in fields requiring thick deposits such as for heat di...Since copper has excellent properties such as malleability and conductivity,it is widely used in the electronics field.Copper sulfate plating is expanding further in fields requiring thick deposits such as for heat dissipation boards and bumps for stress relaxation during semiconductor packaging.In this study,high-speed copper plating at 50 A/dm2 or more was achieved using a jet flow device.In addition,as a result of comparison with the low current density film,the current density had little effect on electrical conductivity and film surface structure.On the other hand,it was confirmed that the etching rate of the high current density film was greatly increased as the crystallites on the film surface became smaller than low current density film.Increase in productivity is expected due to shorter plating time enabled by film deposition at high current density.Furthermore,the increase of etching rate is expected to contribute to the suppression of undercuts that occur when removing the seed layer during wiring and bump fabrication.展开更多
基金financially supported by the National Key Basic Research Program of China(Grant No.2013CB036101)the National Natural Science Foundation of China(Grant No.11702054)
文摘Based on the wave radiation and diffraction theory, this paper investigates a new type breakwater with upper arcshaped plate by using the boundary element method(BEM). By comparing with other three designs of plate type breakwater(lower arc-shaped plate, single horizontal plate and double horizontal plate), this new type breakwater has been proved more effective. The wave exiting force, transmission and reflection coefficients are analyzed and discussed. In order to reveal the wave elimination mechanism of this type of breakwater, the velocity field around the breakwater is obtained. It is shown that:(1) The sway exciting force is minimal.(2) When the ratio of the submergence and wave amplitude is 0.05, the wave elimination effect will increase by 50% compared with other three types of breakwater.(3) The obvious backflow is found above the plate in the velocity field analysis.
文摘Pressure guide plate plays a certain role in the safe operation of elevator.Based on understanding the respective performance of new and old pressure guide plates,this paper analyses the problems existing in the original pressure guide plate.It also conducts stress analysis according to the function of pressure guide plate on elevator,and designs a new type of pressure guide plate combined with technological capability and equipment.According to the stress characteristics,a test device is designed and a comparative test is made between the new type of pressure guide plate and the old in order to test the reliability of the new type of pressure guide plate.The test proves that the new pressure guide plate of elevator can meet the requirements of product use and safe operation of elevator products.
文摘Since copper has excellent properties such as malleability and conductivity,it is widely used in the electronics field.Copper sulfate plating is expanding further in fields requiring thick deposits such as for heat dissipation boards and bumps for stress relaxation during semiconductor packaging.In this study,high-speed copper plating at 50 A/dm2 or more was achieved using a jet flow device.In addition,as a result of comparison with the low current density film,the current density had little effect on electrical conductivity and film surface structure.On the other hand,it was confirmed that the etching rate of the high current density film was greatly increased as the crystallites on the film surface became smaller than low current density film.Increase in productivity is expected due to shorter plating time enabled by film deposition at high current density.Furthermore,the increase of etching rate is expected to contribute to the suppression of undercuts that occur when removing the seed layer during wiring and bump fabrication.
