In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current re...In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current response（TCR） at 136 mm diameter,where the resonance occurs at 2.4kHz and the peak value of 118 dB re 1 μPa/A at 1 m occurs at 12 kHz.Also bolt at a 46mm distance from the center of the head mass offers resonance at 2.4kHz,and the peak value of 115.3 dB re 1 μPa/A at 1m occurs at 11.5kHz.This optimized design is fabricated and molded with polyurethane of 3mm thickness.The prototype was tested at the Acoustic Test Facility（ATF） of National Institute of Ocean Technology（NIOT） for its underwater performances.Based on the result,the fundamental resonance was determined to be 2.18kHz and the peak value of TCR of 182 dB re 1 μPa/A at 1m occurs at 14 kHz.The maximum value of the RS was found to be -190 dB re 1V/μPa at 1m at a frequency of 2.1kHz.展开更多
A two-stage power amplifier operated at 925 MHz was designed and fabricated in Jazz' s 0.35μmSiGe BiCMOS process.It was fully integrated excluding the inductors and the output matching network.Under a single 3.3V...A two-stage power amplifier operated at 925 MHz was designed and fabricated in Jazz' s 0.35μmSiGe BiCMOS process.It was fully integrated excluding the inductors and the output matching network.Under a single 3.3V supply voltage,the off-chip bonding test results indicated that the circuit has a smallsignal gain of more than 24dB,the input and output reflectance are less than- 24dB and-10dB,re-spectively,and the maximal output power is 23.5 dBm.At output power of 23.1 dBm,the PAE(poweradded efficiency)is 30.2%,the IMD2 and IMD3 are less than- 32 dBc and-46 dBc,respectively.The chip size is 1.27mm ×0.9mm.展开更多
Based on the undertaken research, it is explored whether power can affect the judgment made by individual about unethical behavior. Research 1 uses questionnaire as measuring method. The results demonstrate that indiv...Based on the undertaken research, it is explored whether power can affect the judgment made by individual about unethical behavior. Research 1 uses questionnaire as measuring method. The results demonstrate that individuals with different levels of power make judgment on various unethical behaviors. Their judgments are not different. It does not agree with the hypothesis. The reason may lie in that it may be affected by social desirability, or that there exist defects in the design of questionnaire. Research 2 uses laboratory investigation. The results demonstrate that individuals in high-power group conduct unethical behavior more frequently and more fiercely. It agrees with the hypothesis. The inconsistent results of the two researches can be reasonably explained from the two angles of moral permission and moral hypocrisy.展开更多
To meet stringent requirements in vacuum and cleanness for semiconductor manufacturing, a new power drive module for Selective Compliant Assembly Robot Arm （SCARA） type robot has been developed for wafer-transfer. I...To meet stringent requirements in vacuum and cleanness for semiconductor manufacturing, a new power drive module for Selective Compliant Assembly Robot Arm （SCARA） type robot has been developed for wafer-transfer. In order to obtain complete hermetic volume for higher vacuum and prevent leakage of hazardous gases, feedthrough motions involving transfer between the vacuum and motors are achieved by the use of metal bellows and magnetic coupling. An analysis of the coaxial-type magnetic coupling by employing the technique of current sheet model is presented. This approach is proved to be a precise and easy method. The construction of power drive module shows its advantage in maintaining ultrahigh vacuum and also enhances the efficiency for transporting the wafer, as compared with conventional design.展开更多
Novel carbon-carbon ultracapacitors and hybrid lithium-carbon devices are described. New approach to the design of electrode materials and electrochemical systems followed by the improved design of ultracapacitor cell...Novel carbon-carbon ultracapacitors and hybrid lithium-carbon devices are described. New approach to the design of electrode materials and electrochemical systems followed by the improved design of ultracapacitor cells and modules have resulted in prototypes of superior performance that was verified by independent tests in the Institute of Transportation Studies, UC （ultracapacitor） Davis, in JME Inc., in Wayne State University, and in some other labs. All the test results confirm the superlative performance of the devices developed： carbon-carbon ultracapacitors demonstrate the extremely low inner resistance resulting in the highest power capability and efficiency that also alleviates the cooling requirements and improves safety. Our ＂parallel＂ hybrid devices demonstrate substantially higher energy density than competing LIC （lithium ion capacitor） technologies keeping at the same time the high power density, comparable with the best carbon-carbon ultracapacitors available in the market. In order to make ultracapacitor technology even more attractive to automakers, new organic electrolytes （not ionic liquids） have been developed and are currently under testing at temperatures about 100 ℃ and voltages up to 3.0 V.展开更多
International standards impose several constraints concerning the electric power quality and require that the harmonic content of the line current of grid connected equipment is below assigned limits; for this reason,...International standards impose several constraints concerning the electric power quality and require that the harmonic content of the line current of grid connected equipment is below assigned limits; for this reason, operating of AC-DC converters with high power factor and low line current distortion has become essential. In this paper, the prototypal realization of a three-phase AC-DC 48 V power electronic converter for telecom system supplying is described and experimental testing results are discussed. The main constraints in the power supply design are the required power density of about 900 W per dm3 as well as the absence of the neutral wire in the supply grid. The carried out investigation is focused on three-level power converter configurations which are considered in order to reduce voltage rating of power switches. As a result of the reduced voltage, low on-resistance metal-oxide-semiconductor field effect transistors can be used in the power stage, solution which allows to achieve improved efficiency as well as increased switching frequency with respect to the insulated gate bipolar transistors based two-level topologies.展开更多
A method to calculate the reflectivity of the coated cavity facet was proposed, and the distribution of the optical power near the two coated cavity facets was calculated for GaN-based laser diodes. A new design metho...A method to calculate the reflectivity of the coated cavity facet was proposed, and the distribution of the optical power near the two coated cavity facets was calculated for GaN-based laser diodes. A new design method for reducing the optical power at the two cavity facets without changing the output power of laser diodes was discussed, which is helpful to optimize the cavity facet coating and raise the threshold current at which catastrophic optical damage occurs.展开更多
文摘In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current response（TCR） at 136 mm diameter,where the resonance occurs at 2.4kHz and the peak value of 118 dB re 1 μPa/A at 1 m occurs at 12 kHz.Also bolt at a 46mm distance from the center of the head mass offers resonance at 2.4kHz,and the peak value of 115.3 dB re 1 μPa/A at 1m occurs at 11.5kHz.This optimized design is fabricated and molded with polyurethane of 3mm thickness.The prototype was tested at the Acoustic Test Facility（ATF） of National Institute of Ocean Technology（NIOT） for its underwater performances.Based on the result,the fundamental resonance was determined to be 2.18kHz and the peak value of TCR of 182 dB re 1 μPa/A at 1m occurs at 14 kHz.The maximum value of the RS was found to be -190 dB re 1V/μPa at 1m at a frequency of 2.1kHz.
基金Supported by the High Technology Research and Development Programme of China (2006AA03Z418)
文摘A two-stage power amplifier operated at 925 MHz was designed and fabricated in Jazz' s 0.35μmSiGe BiCMOS process.It was fully integrated excluding the inductors and the output matching network.Under a single 3.3V supply voltage,the off-chip bonding test results indicated that the circuit has a smallsignal gain of more than 24dB,the input and output reflectance are less than- 24dB and-10dB,re-spectively,and the maximal output power is 23.5 dBm.At output power of 23.1 dBm,the PAE(poweradded efficiency)is 30.2%,the IMD2 and IMD3 are less than- 32 dBc and-46 dBc,respectively.The chip size is 1.27mm ×0.9mm.
文摘Based on the undertaken research, it is explored whether power can affect the judgment made by individual about unethical behavior. Research 1 uses questionnaire as measuring method. The results demonstrate that individuals with different levels of power make judgment on various unethical behaviors. Their judgments are not different. It does not agree with the hypothesis. The reason may lie in that it may be affected by social desirability, or that there exist defects in the design of questionnaire. Research 2 uses laboratory investigation. The results demonstrate that individuals in high-power group conduct unethical behavior more frequently and more fiercely. It agrees with the hypothesis. The inconsistent results of the two researches can be reasonably explained from the two angles of moral permission and moral hypocrisy.
文摘To meet stringent requirements in vacuum and cleanness for semiconductor manufacturing, a new power drive module for Selective Compliant Assembly Robot Arm （SCARA） type robot has been developed for wafer-transfer. In order to obtain complete hermetic volume for higher vacuum and prevent leakage of hazardous gases, feedthrough motions involving transfer between the vacuum and motors are achieved by the use of metal bellows and magnetic coupling. An analysis of the coaxial-type magnetic coupling by employing the technique of current sheet model is presented. This approach is proved to be a precise and easy method. The construction of power drive module shows its advantage in maintaining ultrahigh vacuum and also enhances the efficiency for transporting the wafer, as compared with conventional design.
文摘Novel carbon-carbon ultracapacitors and hybrid lithium-carbon devices are described. New approach to the design of electrode materials and electrochemical systems followed by the improved design of ultracapacitor cells and modules have resulted in prototypes of superior performance that was verified by independent tests in the Institute of Transportation Studies, UC （ultracapacitor） Davis, in JME Inc., in Wayne State University, and in some other labs. All the test results confirm the superlative performance of the devices developed： carbon-carbon ultracapacitors demonstrate the extremely low inner resistance resulting in the highest power capability and efficiency that also alleviates the cooling requirements and improves safety. Our ＂parallel＂ hybrid devices demonstrate substantially higher energy density than competing LIC （lithium ion capacitor） technologies keeping at the same time the high power density, comparable with the best carbon-carbon ultracapacitors available in the market. In order to make ultracapacitor technology even more attractive to automakers, new organic electrolytes （not ionic liquids） have been developed and are currently under testing at temperatures about 100 ℃ and voltages up to 3.0 V.
文摘International standards impose several constraints concerning the electric power quality and require that the harmonic content of the line current of grid connected equipment is below assigned limits; for this reason, operating of AC-DC converters with high power factor and low line current distortion has become essential. In this paper, the prototypal realization of a three-phase AC-DC 48 V power electronic converter for telecom system supplying is described and experimental testing results are discussed. The main constraints in the power supply design are the required power density of about 900 W per dm3 as well as the absence of the neutral wire in the supply grid. The carried out investigation is focused on three-level power converter configurations which are considered in order to reduce voltage rating of power switches. As a result of the reduced voltage, low on-resistance metal-oxide-semiconductor field effect transistors can be used in the power stage, solution which allows to achieve improved efficiency as well as increased switching frequency with respect to the insulated gate bipolar transistors based two-level topologies.
基金supported by the National Natural Science Foundation of China (Grant Nos.60506001,60976045,60836003,60776047 and 61076119) the National Basic Research Program of China ("973" Project) (Grant No. 2007CB936700)the National Science Foundation for Distinguished Yong Scholar (Grant No. 60925017)
文摘A method to calculate the reflectivity of the coated cavity facet was proposed, and the distribution of the optical power near the two coated cavity facets was calculated for GaN-based laser diodes. A new design method for reducing the optical power at the two cavity facets without changing the output power of laser diodes was discussed, which is helpful to optimize the cavity facet coating and raise the threshold current at which catastrophic optical damage occurs.
