Deduced the relationship between the power factor (PF) and the angular fre-quency according to the simplified equivalent circuit of asynchronous motor, forming a power factor auto-control system. An anti-interference ...Deduced the relationship between the power factor (PF) and the angular fre-quency according to the simplified equivalent circuit of asynchronous motor, forming a power factor auto-control system. An anti-interference circuit was also introduced in the middle voltage link of inverter to avoid the shift of the optimum PF point caused by the change of the load and the reliable run of the control system was assured. The experi-ment results show that it has a good self-adaptation in the whole scope of speed ad-justment and an obvious economization on energy while it runs under load.展开更多
In this paper, a high power factor LED driver with hot swap, smart output voltage regulation and dimming control is proposed. The dimming control is used to change LED brightness. During converter is working, the hot ...In this paper, a high power factor LED driver with hot swap, smart output voltage regulation and dimming control is proposed. The dimming control is used to change LED brightness. During converter is working, the hot swap function supply users to remove and insert LED module. The smart output voltage can regulate quickly and rightly output voltage in different number of LED series connection. The system consists two stages, one is 50 W flyback converter which is used as power factor corrector, it is input source is 110-220 V, PF （power factor） is about 0,994. The other is Boost DC/DC converter, it can offer 35-60 V of output voltage. Finally, a prototype has been built and tested. The simulation and experimental results are shown to verify the feasibility of the proposed method.展开更多
Objective To observe the efficacy differences between electroacupuncture （EA） and physiotherapy （PT） on the proprioception of athletes with functional ankle instability （FAI）. Methods Fifty athletes with FAI wer...Objective To observe the efficacy differences between electroacupuncture （EA） and physiotherapy （PT） on the proprioception of athletes with functional ankle instability （FAI）. Methods Fifty athletes with FAI were randomly divided into an EA group and a PT group. The EA group was treated with EA at Jiexi （解溪 ST 41）, Kunlun （昆仑 BL 60）, Qjuxu （丘墟 GB 40） and Ashi points, and the PT group was treated with low frequency electrical stimulation and infrared radiation at medial malleolus and lateral malleolus, thrice each week for consecutive 8 weeks. The joint position sense： active （JPSA）, joint position sense： passive （JPSP） and Kinaesthesia （KT） were assessed at the ankle by use of Biodex System isokinetic dynamometer to test the proprioception before and after the treatment. Results In the EA group, JPSA of 11.09°±3.1° and JPSP of 9.67°±2.8° before the treatment were reduced to 9.14°±4.0° and 6.89°±3.3° respectively after the treatment, and there were statistically significant differences in comparison between pre- and post-treatment （all P〈0.05）. Comparison between the EA group and the PT group, there were significant differences in JPSA and JPSP （all P〈0.05）, no significant difference in KT （P〉0.05）. There were no significant differences in the indices of JPSA, JPSP and KT in the PT group after the treatment than those before the treatment （all P〉0.05）. Conclusion EA can effectively improve the proprioception of athletes with FAI and achieve a better efficacy as compared with the conventional physiotherapy.展开更多
基金Supported by Liaoning Educational Foundation(202183386)
文摘Deduced the relationship between the power factor (PF) and the angular fre-quency according to the simplified equivalent circuit of asynchronous motor, forming a power factor auto-control system. An anti-interference circuit was also introduced in the middle voltage link of inverter to avoid the shift of the optimum PF point caused by the change of the load and the reliable run of the control system was assured. The experi-ment results show that it has a good self-adaptation in the whole scope of speed ad-justment and an obvious economization on energy while it runs under load.
文摘In this paper, a high power factor LED driver with hot swap, smart output voltage regulation and dimming control is proposed. The dimming control is used to change LED brightness. During converter is working, the hot swap function supply users to remove and insert LED module. The smart output voltage can regulate quickly and rightly output voltage in different number of LED series connection. The system consists two stages, one is 50 W flyback converter which is used as power factor corrector, it is input source is 110-220 V, PF （power factor） is about 0,994. The other is Boost DC/DC converter, it can offer 35-60 V of output voltage. Finally, a prototype has been built and tested. The simulation and experimental results are shown to verify the feasibility of the proposed method.
基金Supported by Shanghai Sports Bureau Sciences Program:09 TF 019
文摘Objective To observe the efficacy differences between electroacupuncture （EA） and physiotherapy （PT） on the proprioception of athletes with functional ankle instability （FAI）. Methods Fifty athletes with FAI were randomly divided into an EA group and a PT group. The EA group was treated with EA at Jiexi （解溪 ST 41）, Kunlun （昆仑 BL 60）, Qjuxu （丘墟 GB 40） and Ashi points, and the PT group was treated with low frequency electrical stimulation and infrared radiation at medial malleolus and lateral malleolus, thrice each week for consecutive 8 weeks. The joint position sense： active （JPSA）, joint position sense： passive （JPSP） and Kinaesthesia （KT） were assessed at the ankle by use of Biodex System isokinetic dynamometer to test the proprioception before and after the treatment. Results In the EA group, JPSA of 11.09°±3.1° and JPSP of 9.67°±2.8° before the treatment were reduced to 9.14°±4.0° and 6.89°±3.3° respectively after the treatment, and there were statistically significant differences in comparison between pre- and post-treatment （all P〈0.05）. Comparison between the EA group and the PT group, there were significant differences in JPSA and JPSP （all P〈0.05）, no significant difference in KT （P〉0.05）. There were no significant differences in the indices of JPSA, JPSP and KT in the PT group after the treatment than those before the treatment （all P〉0.05）. Conclusion EA can effectively improve the proprioception of athletes with FAI and achieve a better efficacy as compared with the conventional physiotherapy.
