For years,scientists believed that astrocytes,the star-shaped brain cells,only had two options-become helpful protectors that shield the brain or become harmful destroyers that damage brain tissue.But a new discovery ...For years,scientists believed that astrocytes,the star-shaped brain cells,only had two options-become helpful protectors that shield the brain or become harmful destroyers that damage brain tissue.But a new discovery shows this isn’t the full story.展开更多
Some Over-Current Limit Control strategies are analyzed and designed to meet the demands of high reliability and rapid dynamic response in the aeronautical power supply applications. The control schemes are both effec...Some Over-Current Limit Control strategies are analyzed and designed to meet the demands of high reliability and rapid dynamic response in the aeronautical power supply applications. The control schemes are both effective in DC-DC converters and DC-AC converters. Controller models are set up, and the over-current limit operation principles of analogy and digital control are analyzed too. An 800VA aeronautical power supply bas been constructed to verify the performance of the proposed control strategy in various cases such as the sudden load change and the constant load. The analysis and experiments confirm the advantages of the proposed over-current limit strategies as follows: simple,effective and reliable.展开更多
A novel type of leakage current protector chip,implemented in the mixed-signal 0.6μm CMOS process,is presented. This chip has the advantages of low power dissipation (10mW), accurate protection control based on dig...A novel type of leakage current protector chip,implemented in the mixed-signal 0.6μm CMOS process,is presented. This chip has the advantages of low power dissipation (10mW), accurate protection control based on digital response delay time and integration of multi-functions such as leakage current/over-voltage/over-load detection and protection,auto switch-on and so forth. Additionally, the chip is programmable to suit different three-level protection applications with a high anti-interference ability.展开更多
文摘For years,scientists believed that astrocytes,the star-shaped brain cells,only had two options-become helpful protectors that shield the brain or become harmful destroyers that damage brain tissue.But a new discovery shows this isn’t the full story.
基金the National Natural Science Foundation of China (Grant No.50237030).
文摘Some Over-Current Limit Control strategies are analyzed and designed to meet the demands of high reliability and rapid dynamic response in the aeronautical power supply applications. The control schemes are both effective in DC-DC converters and DC-AC converters. Controller models are set up, and the over-current limit operation principles of analogy and digital control are analyzed too. An 800VA aeronautical power supply bas been constructed to verify the performance of the proposed control strategy in various cases such as the sudden load change and the constant load. The analysis and experiments confirm the advantages of the proposed over-current limit strategies as follows: simple,effective and reliable.
文摘A novel type of leakage current protector chip,implemented in the mixed-signal 0.6μm CMOS process,is presented. This chip has the advantages of low power dissipation (10mW), accurate protection control based on digital response delay time and integration of multi-functions such as leakage current/over-voltage/over-load detection and protection,auto switch-on and so forth. Additionally, the chip is programmable to suit different three-level protection applications with a high anti-interference ability.