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 new system-corrected CMOS audio power AMP is presented. Consisting of four single-end OPAs,this structure is a pseudo-differential system. Compared to conventional CMOS power AMPs, it has the merits of low power con...A new system-corrected CMOS audio power AMP is presented. Consisting of four single-end OPAs,this structure is a pseudo-differential system. Compared to conventional CMOS power AMPs, it has the merits of low power consumption, extremely low THD,easy compensation, and good driving capability. With 1st silicon 0.25μm 1P4M CMOS technology and a 3V power supply,the output range can be 4Vpp when driving an 8Ω‖ 300pF load, while its power dissipation is less than 3mW. The THD is better than 0. 003% at 1kHz. A new over-current protection circuit, which can effectively protect the power output circuits on the chip, is also demonstrated.展开更多
[Objective] 7 indictors of wheat genotype Heng 9966, its parents and their closely related varieties were analyzed based on the 1000-grain weight, sedimentation value and traits of selected grains in DUS test, so as t...[Objective] 7 indictors of wheat genotype Heng 9966, its parents and their closely related varieties were analyzed based on the 1000-grain weight, sedimentation value and traits of selected grains in DUS test, so as to provide references for the protection of variety intellectual property. [Method] Testing comparison and statistical analysis were conducted to the dormant seeds of winter wheat genotype 9966, parents of Liangxing 99 and Liangxing 96 aw well as the closely related variety of the parents, Jimai 22. [Result] Heng 9966 showed a difference of 2 codes in 1000-grain weight and sedimentation value from the above-mentioned 3 genotypes, and the variant analysis reached the extremely significant level of 0.01. And it also showed extremely significant difference at the level of 0.01 with Liangxing 66 in grain length, with Liangxing 66 and Jimai 22 in grain width, with Liangxing 66 in grain area, with Liangxing 66 and Jimai 22 in grain perimeter. [Conclusion] Heng 9966 had significant distinctness from its parents and their closely related variety, and grain shape can be used as a reference indicator for variety distinctness for the protection of variety intellectual property.展开更多
Along with the emergence and ma- turity of 100Gbit/s technologies, numbers of trial and commercial 100Gbit/s Wavelength Division Multiplexing （WDM） systems have been established worldwide. The research- oriented lab...Along with the emergence and ma- turity of 100Gbit/s technologies, numbers of trial and commercial 100Gbit/s Wavelength Division Multiplexing （WDM） systems have been established worldwide. The research- oriented lab tests of 100Gbit/s WDM systems were done by China Unicorn in 2012. The 100Gbit/s technologies of polarization multi- plex-quadrature phase shift keying with co- herent detection from multiple vendors have been studied. There are some further issues to be specified before the commercial application of 100Gbit/s WDM system is implemented in large scale in backbone network, including optical pertbnnance parameters, optical per- lbrmance monitoring of 100Gbit/s system, protection mechanism, selection of client in- terfhce and comprehensive Operation, Ad- ministration and Maintenance （OAM）.展开更多
LHCD experiment has been carried through in HL-1M tokamak since 1995, and the work is successful. This years the LHCD experiment would go ahead on the HL-2A tokamak that had been improved from HL-1M system.
This paper introduces the design of the TZ-2 high voltage modulator for electron cyclotron resonance heating （ECRH） on HL-2A tokamak. The high voltage power supplies （HVPS） for the cyclotron have to operate advant...This paper introduces the design of the TZ-2 high voltage modulator for electron cyclotron resonance heating （ECRH） on HL-2A tokamak. The high voltage power supplies （HVPS） for the cyclotron have to operate advantageously and flexibly, with high stabilization and good insulation to high-voltage. Moreover, the HVPS must carry out the function of protection quickly, for insure the security of people and devices in the experiment on HL-2A. In this year, the HVPS with these modulators satisfies the requirement of the experiment of HL-2A.展开更多
Digital fingerprinting is an emerging technology to protect multimedia data from piracy, where each distributed copy is labeled with unique identification information. In coded fingerprinting, each codeword of the ant...Digital fingerprinting is an emerging technology to protect multimedia data from piracy, where each distributed copy is labeled with unique identification information. In coded fingerprinting, each codeword of the anti-collusion code is used to represent a user＇s fingerprint. In real-world applications, the number of potential users can be very large and hence, the used anti- collusion code should be easy to construct and have as many codewords as possible. This paper proposes a simple coded fingerprinting scheme, where the anti- collusion code is constructed with an identity matrix. The main advantage of our scheme is its simplicity, as a large number of fingerprints can easily be generated to accommodate a large number of users. To improve collusion resistance, some transformations are performed on the original fingerprint in the embedding phase and the corresponding inverse transformations are performed on the extracted sequence in the detection phase.展开更多
In DC micro grids and networks,DC-DC power converters having a large number of semiconductor-based power electronic devices are usually adopted to interconnect the renewable sources and flexible loads.Most of the semi...In DC micro grids and networks,DC-DC power converters having a large number of semiconductor-based power electronic devices are usually adopted to interconnect the renewable sources and flexible loads.Most of the semiconductor-based devices suffer from poor fault withstanding abilities,but conventional power electronic protection schemes have the bottlenecks of the time-delay,self-malfunction and mis-judgement.This paper presents a novel solution using the superconducting fault current limiter(SFCL)to protect a power electronic device and extend the usage to a micro grid.This SFCL is actually a self-triggering,recoverable,and passive current limiter,which does not involve any additional circuit hardware and software.Experimental investigations and simulation analyses clarify the feasibility of using this superconductor-based protection scheme to implement the self-acting fail-safe protection of DC-DC converters.Further system-level simulations explore the SFCL to suppress the over-current and stabilize the bus voltage of a photovoltaic based DC micro grid,particularly facing millisecond-level transients and faults.Our experimental and theoretical investigations lay some technical bases to establish a superconductor-semiconductor-coupled interdisciplinary application from the view from the applied superconductivity,to power electronics,and to micro grids.展开更多
The anatomic relationship of oral and maxillofacial region is very com-plex,due to the large number of sinuses,cavities and spaces,and also closely related to the brain.The diagnosis of oral and maxillofacial lesions ...The anatomic relationship of oral and maxillofacial region is very com-plex,due to the large number of sinuses,cavities and spaces,and also closely related to the brain.The diagnosis of oral and maxillofacial lesions usually depends on the imaging examination.The conventional imaging methods are common CT and X-ray plain films.In recent years,with the rapid development of medical science and technology,more intuitive and vivid three-dimensional images have been applied in the diagnosis and treatment of oral and maxillofacial diseases.Therefore,CT three-dimensional imaging technology has been widely used in clinical practice.This paper reviews this topic.展开更多
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 new system-corrected CMOS audio power AMP is presented. Consisting of four single-end OPAs,this structure is a pseudo-differential system. Compared to conventional CMOS power AMPs, it has the merits of low power consumption, extremely low THD,easy compensation, and good driving capability. With 1st silicon 0.25μm 1P4M CMOS technology and a 3V power supply,the output range can be 4Vpp when driving an 8Ω‖ 300pF load, while its power dissipation is less than 3mW. The THD is better than 0. 003% at 1kHz. A new over-current protection circuit, which can effectively protect the power output circuits on the chip, is also demonstrated.
基金Supported by the"Creation and Application of Wheat Hybrid with Strong Heterosis in Huang-Huai Wheat Area"of the National Key Research and Development Plan(2016YFD0101602)the"Wheat Mutation Breeding Technology Innovation and Variety Creation"of the National Key Research and Development Plan(2016YFD0102101)+1 种基金the China Agriculture Research System for Wheat(CARS-3-2)the Industrial Technology Research System for Wheat of Hebei Province~~
文摘[Objective] 7 indictors of wheat genotype Heng 9966, its parents and their closely related varieties were analyzed based on the 1000-grain weight, sedimentation value and traits of selected grains in DUS test, so as to provide references for the protection of variety intellectual property. [Method] Testing comparison and statistical analysis were conducted to the dormant seeds of winter wheat genotype 9966, parents of Liangxing 99 and Liangxing 96 aw well as the closely related variety of the parents, Jimai 22. [Result] Heng 9966 showed a difference of 2 codes in 1000-grain weight and sedimentation value from the above-mentioned 3 genotypes, and the variant analysis reached the extremely significant level of 0.01. And it also showed extremely significant difference at the level of 0.01 with Liangxing 66 in grain length, with Liangxing 66 and Jimai 22 in grain width, with Liangxing 66 in grain area, with Liangxing 66 and Jimai 22 in grain perimeter. [Conclusion] Heng 9966 had significant distinctness from its parents and their closely related variety, and grain shape can be used as a reference indicator for variety distinctness for the protection of variety intellectual property.
基金supported by the China Unicom under the project of the research on 100Gbit/s high bitrate transport technology
文摘Along with the emergence and ma- turity of 100Gbit/s technologies, numbers of trial and commercial 100Gbit/s Wavelength Division Multiplexing （WDM） systems have been established worldwide. The research- oriented lab tests of 100Gbit/s WDM systems were done by China Unicorn in 2012. The 100Gbit/s technologies of polarization multi- plex-quadrature phase shift keying with co- herent detection from multiple vendors have been studied. There are some further issues to be specified before the commercial application of 100Gbit/s WDM system is implemented in large scale in backbone network, including optical pertbnnance parameters, optical per- lbrmance monitoring of 100Gbit/s system, protection mechanism, selection of client in- terfhce and comprehensive Operation, Ad- ministration and Maintenance （OAM）.
文摘LHCD experiment has been carried through in HL-1M tokamak since 1995, and the work is successful. This years the LHCD experiment would go ahead on the HL-2A tokamak that had been improved from HL-1M system.
文摘This paper introduces the design of the TZ-2 high voltage modulator for electron cyclotron resonance heating （ECRH） on HL-2A tokamak. The high voltage power supplies （HVPS） for the cyclotron have to operate advantageously and flexibly, with high stabilization and good insulation to high-voltage. Moreover, the HVPS must carry out the function of protection quickly, for insure the security of people and devices in the experiment on HL-2A. In this year, the HVPS with these modulators satisfies the requirement of the experiment of HL-2A.
文摘Digital fingerprinting is an emerging technology to protect multimedia data from piracy, where each distributed copy is labeled with unique identification information. In coded fingerprinting, each codeword of the anti-collusion code is used to represent a user＇s fingerprint. In real-world applications, the number of potential users can be very large and hence, the used anti- collusion code should be easy to construct and have as many codewords as possible. This paper proposes a simple coded fingerprinting scheme, where the anti- collusion code is constructed with an identity matrix. The main advantage of our scheme is its simplicity, as a large number of fingerprints can easily be generated to accommodate a large number of users. To improve collusion resistance, some transformations are performed on the original fingerprint in the embedding phase and the corresponding inverse transformations are performed on the extracted sequence in the detection phase.
基金the National Natural Science Foundation of China[Grant No.51807128].
文摘In DC micro grids and networks,DC-DC power converters having a large number of semiconductor-based power electronic devices are usually adopted to interconnect the renewable sources and flexible loads.Most of the semiconductor-based devices suffer from poor fault withstanding abilities,but conventional power electronic protection schemes have the bottlenecks of the time-delay,self-malfunction and mis-judgement.This paper presents a novel solution using the superconducting fault current limiter(SFCL)to protect a power electronic device and extend the usage to a micro grid.This SFCL is actually a self-triggering,recoverable,and passive current limiter,which does not involve any additional circuit hardware and software.Experimental investigations and simulation analyses clarify the feasibility of using this superconductor-based protection scheme to implement the self-acting fail-safe protection of DC-DC converters.Further system-level simulations explore the SFCL to suppress the over-current and stabilize the bus voltage of a photovoltaic based DC micro grid,particularly facing millisecond-level transients and faults.Our experimental and theoretical investigations lay some technical bases to establish a superconductor-semiconductor-coupled interdisciplinary application from the view from the applied superconductivity,to power electronics,and to micro grids.
文摘The anatomic relationship of oral and maxillofacial region is very com-plex,due to the large number of sinuses,cavities and spaces,and also closely related to the brain.The diagnosis of oral and maxillofacial lesions usually depends on the imaging examination.The conventional imaging methods are common CT and X-ray plain films.In recent years,with the rapid development of medical science and technology,more intuitive and vivid three-dimensional images have been applied in the diagnosis and treatment of oral and maxillofacial diseases.Therefore,CT three-dimensional imaging technology has been widely used in clinical practice.This paper reviews this topic.
