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心脏病急救电振器
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《金融与经济》 1988年第2期64-64,共1页
根据统计美国每年都有大约一百五十万心脏病患者,在其中有1/4病例是属于非住院突发性的,这些人士往往得到突然的病发,在没有紧急治疗的情况下,侥幸生还的不足百分之五。可是最近美国新泽西洲一间公司已为该类病患者带来一个莫大喜讯,因... 根据统计美国每年都有大约一百五十万心脏病患者,在其中有1/4病例是属于非住院突发性的,这些人士往往得到突然的病发,在没有紧急治疗的情况下,侥幸生还的不足百分之五。可是最近美国新泽西洲一间公司已为该类病患者带来一个莫大喜讯,因为他们研制了一种心脏病急救系统,能迅速治疗突发性心脏病患。 展开更多
关键词 心脏病患者 电振器 突发性 急救箱 非住院 治疗 微处理机 系统装置 显示屏
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基于x-LMS算法的直升机主动消振电力作动器系统研究
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作者 郝振洋 杨健 +2 位作者 张嘉文 曹鑫 王涛 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第1期53-65,共13页
直升机前飞时,气动环境会导致不同方位角的桨叶出现气动载荷的瞬间不对称,通过基础结构传递会在机身形成大幅度的低频振动。为了消除多方向幅值变化的振动力,利用结构响应主动控制原理,设计了基于x-LMS算法的主动消振电力作动器系统,并... 直升机前飞时,气动环境会导致不同方位角的桨叶出现气动载荷的瞬间不对称,通过基础结构传递会在机身形成大幅度的低频振动。为了消除多方向幅值变化的振动力,利用结构响应主动控制原理,设计了基于x-LMS算法的主动消振电力作动器系统,并进行了减振实验。首先,通过比较确定了单台作动器中两台电机同向旋转的方案。通过两台作动器的组合使用,推导出输出力的数学模型。其次,采用负载相位差交叉耦合的控制策略设计系统控制框图。针对存在耦合的相位外环,通过回差阵特征值法确定满足系统稳定裕度要求的参数范围,再根据灵敏度函数和输入跟踪性能在所得的参数稳定域内寻找最优解。然后,提出了基于x-LMS算法的直升机主动振动控制系统,并通过仿真验证了该系统的减振效果。最后,研制的实验样机进行了动稳态实验以及减振实验,验证了系统的实际减振效果。 展开更多
关键词 结构响应主动控制 力作动 回差阵特征值法 x-LMS算法
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用电磁悬浮动力吸振器控制转子多频不平衡响应的方法 被引量:9
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作者 宋方臻 冯德振 +1 位作者 宋波 孙选 《机械科学与技术》 CSCD 北大核心 2004年第2期170-173,共4页
在转子上采用电磁悬浮动力吸振器 ,可以解决转子振动控制中的许多难题。它不必安装在轴承位置 ,因此可以兼顾转子的静、动态特性要求 ;不随转子旋转 ,激励控制方便 ,且不会因吸振器运动而派生出更大的离心力问题 ;因非接触又不随转子旋... 在转子上采用电磁悬浮动力吸振器 ,可以解决转子振动控制中的许多难题。它不必安装在轴承位置 ,因此可以兼顾转子的静、动态特性要求 ;不随转子旋转 ,激励控制方便 ,且不会因吸振器运动而派生出更大的离心力问题 ;因非接触又不随转子旋转 ,不会增加转子的转动惯量 ,原则上其质量可以有较大的选择余地 ;没有外传力或外传力很小。因此 ,电磁悬浮动力吸振器具有重大的工程应用价值。在给出转子 +电磁悬浮动力吸振器系统模型的基础上 ,采用输出调节器理论 ,设计了电磁悬浮动力吸振器控制系统。控制系统的主要目标是 :在指定的多个频率位置 ,将转子的不平衡响应减为零 ,而在其余较宽的频率范围内 ,尽量抑制不平衡响应的水平 ,使之处于非共振量级。仿真分析验证了所提出方法的有效性。 展开更多
关键词 转子 磁悬浮动力吸
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旋转偏心质量块式消振电力作动器建模与控制 被引量:1
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作者 郝振洋 王涛 +2 位作者 曹鑫 甘渊 俞强 《振动工程学报》 EI CSCD 北大核心 2022年第1期209-219,共11页
直升机等非固定翼飞行器在飞行状态时由桨叶旋转所产生的周期性低频振动会通过刚性机体传递至驾驶舱、航空发动机以及起落架等部位,会造成机体的持续振动,严重时会影响驾驶员的生命安全。提出了旋转偏心质量块式消振电力作动器,并开展... 直升机等非固定翼飞行器在飞行状态时由桨叶旋转所产生的周期性低频振动会通过刚性机体传递至驾驶舱、航空发动机以及起落架等部位,会造成机体的持续振动,严重时会影响驾驶员的生命安全。提出了旋转偏心质量块式消振电力作动器,并开展了控制方法研究。从理论上推导了旋转偏心质量块式消振电力作动器的输出力模型以及负载转矩模型;提出基于双电机并行独立控制的电力作动器输出力伺服控制策略,在复频域进行了稳定性分析,并针对正弦波非线性负载扰动带来的转矩脉动问题,对双电机并行独立控制策略展开了优化设计,通过负载前馈控制使系统具备良好的鲁棒性和抗干扰性;研制了重量为14 kg的实验样机并完成了优化控制策略前后电力作动器稳态、动态性能的对比验证实验。结果表明,优化控制策略下的作动器输出力动稳态性能满足各项技术指标要求。 展开更多
关键词 动控制 力作动 并行独立控制 负载前馈控制 鲁棒性
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并行独立控制策略下消振电力作动器系统
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作者 郝振洋 张凤婷 +1 位作者 杨健 曹鑫 《航空学报》 EI CAS CSCD 北大核心 2024年第13期366-380,共15页
传统消振电力作动器采用交叉耦合控制策略实现输出力伺服控制,但该控制策略存在耦合控制项,影响输出力响应的快速性、准确性,降低了作动器的减振效率;同时在直流(DC)母线侧产生不满足国军标要求的冲击电压,直接威胁了直升机的飞行安全... 传统消振电力作动器采用交叉耦合控制策略实现输出力伺服控制,但该控制策略存在耦合控制项,影响输出力响应的快速性、准确性,降低了作动器的减振效率;同时在直流(DC)母线侧产生不满足国军标要求的冲击电压,直接威胁了直升机的飞行安全。基于此,提出了并行独立控制策略下的消振电力作动器伺服控制系统,首先对系统的给定输出力进行解耦设计,以实现系统多电机并行独立运行。其次,利用主导极点法和最大灵敏度法分别从时域和频域角度设计系统的动稳态特性及鲁棒性。最后,搭建实验平台进行控制策略对比,标幺化实验数据表明,系统在变方向时响应精度提升3.6%,响应时间减少40%;在变相位时响应精度提升1.5%,响应时间减少31%;直流母线侧的电压冲击值减少了8 V,进而验证了并行独立控制策略的有效性及其优势。 展开更多
关键词 力作动 机同步控制 并行独立控制策略 交叉耦合控制策略 压冲击
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定量秤振动给料机构的数控方法
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作者 牟燕妮 魏明才 《衡器》 1995年第6期17-19,共3页
在用电振器送料的定量秤中,只用一台电振器而要实现送料速度的改变,其方法有多种。本文介绍的是一种通过数控手段调节可控硅导通甬而改变电振器给料速度的方法。
关键词 定量秤 电振器 给料速度 数字控制
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消振电力作动器用位置环解耦控制策略 被引量:3
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作者 郝振洋 王涛 +1 位作者 曹鑫 朱涛 《航空学报》 EI CAS CSCD 北大核心 2022年第8期599-614,共16页
消振电力作动器采用四台电机各自独立驱动四个偏心质量块的形式实现减振,传统的并行控制策略会因为在系统输出端存在强耦合而导致控制效果不佳。针对以上问题,首先建立了作动器输出力的数学模型,提出了消振电力作动器用位置环解耦控制策... 消振电力作动器采用四台电机各自独立驱动四个偏心质量块的形式实现减振,传统的并行控制策略会因为在系统输出端存在强耦合而导致控制效果不佳。针对以上问题,首先建立了作动器输出力的数学模型,提出了消振电力作动器用位置环解耦控制策略,并将广义频率法和主导极点法相结合应用于控制系统的参数设计上。然后,分析了系统的动态性能,并通过回差矩阵奇异值法等稳定裕度量测方法计算出了解耦控制系统的稳定裕度,结果表明本文所设计的系统具有良好的动态特性和鲁棒性。最后,研制出了原理样机,实验验证了控制策略的有效性和参数设计的合理性。 展开更多
关键词 力作动 解耦控制 主导极点法 广义频率法 回差矩阵奇异值法
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Fast-Lock Low-Jitter PLL with a Simple Phase-Frequency Detector 被引量:3
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作者 陈莹梅 王志功 章丽 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第1期88-92,共5页
A fast-locking, low-jitter, phase-locked loop (PLL) with a simple phase-frequency detector is proposed. The phase-frequency detector is composed of only two XOR gates. It simultaneously achieves low jitter and short... A fast-locking, low-jitter, phase-locked loop (PLL) with a simple phase-frequency detector is proposed. The phase-frequency detector is composed of only two XOR gates. It simultaneously achieves low jitter and short locking time. The voltage-controlled oscillator within the PLL consists of four-stage ring oscillators which are coupled to each other and oscillate with the same frequency and a phase shift of 45. The PLL is fabricated in 0. 1Stem CMOS technology. The measured phase noise of the PLL output at 500kHz offset from the 5GHz center frequency is - 102.6dBc/Hz. The circuit exhibits a capture range of 280MHz and a low RMS jitter of 2.06ps. The power dissipation excluding the output buffers is only 21.6roW at a 1.8V supply. 展开更多
关键词 phase locked loop phase-frequency detector voltage-controlled oscillator JITTER locking time
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A Low Jitter PLL in a 90nm CMOS Digital Process 被引量:5
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作者 尹海丰 王峰 +1 位作者 刘军 毛志刚 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第8期1511-1516,共6页
A low jitter phase-locked loop (PLL) that does not need analog resistors and capacitors is designed and fabrica- ted in a 90nm CMOS digital process. The metal parasitic capacitor is used in the PLL loop filter. Test... A low jitter phase-locked loop (PLL) that does not need analog resistors and capacitors is designed and fabrica- ted in a 90nm CMOS digital process. The metal parasitic capacitor is used in the PLL loop filter. Test results show that when the PLL is locked on 1. 989GHz, the RMS jitter is 3. 7977ps, the peak-to-peak jitter is 31. 225ps, and the power con- sumption is about 9mW. The locked output frequency range is from 125MHz to 2.7GHz. 展开更多
关键词 PLL PFD charge pump VCO
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Low phase noise LC VCO design in CMOS technology 被引量:2
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作者 李智群 王志功 +1 位作者 张立国 徐勇 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期6-9,共4页
This paper presents the design and the experimental measurements of two complementary metal-oxide-semiconductor (CMOS) LC-tuned voltage controlled oscillators (VCO) implemented in a 0.18 μm 6-metal-layer mixed-signal... This paper presents the design and the experimental measurements of two complementary metal-oxide-semiconductor (CMOS) LC-tuned voltage controlled oscillators (VCO) implemented in a 0.18 μm 6-metal-layer mixed-signal/RF CMOS technology. The design methodologies and approaches for the optimization of the ICs are presented. The first design is optimized for mixed-signal transistor, oscillated at 2.64 GHz with a phase noise of -93.5 dBc/Hz at 500 kHz offset. The second one optimized for RF transistor, using the same architecture, oscillated at 2.61 GHz with a phase noise of -95.8 dBc/Hz at 500 kHz offset. Under a 2 V supply, the power dissipation is 8 mW, and the maximum buffered output power for mixed-signal and RF transistor are -7 dBm and -5.4 dBm, respectively. Both kinds of oscillators make use of on-chip components only, allowing for simple and robust integration. 展开更多
关键词 CMOS integrated circuits Integrated circuit layout TRANSISTORS
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Design of a 2.5GHz Low Phase-Noise LC-VCO in 0.35μm SiGe BiCMOS
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作者 张健 陈立强 +2 位作者 李志强 陈普峰 张海英 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第5期827-831,共5页
This paper introduces a 2.5GHz low phase-noise cross-coupled LC-VCO realized in 0.35μm SiGe BiCMOS technology. The conventional definition of a VCO operating regime is revised from a new perspective. Analysis shows t... This paper introduces a 2.5GHz low phase-noise cross-coupled LC-VCO realized in 0.35μm SiGe BiCMOS technology. The conventional definition of a VCO operating regime is revised from a new perspective. Analysis shows the importance of inductance and bias current selection for oscillator phase noise optimization. Differences between CMOS and BJT VCO design strategy are then analyzed and the conclusions are summarized. In this implementation, bonding wires form the resonator to improve the phase noise performance. The VCO is then integrated with other components to form a PLL frequency synthesizer with a loop bandwidth of 30kHz. Measurement shows a phase noise of - 95dBc/Hz at 100kHz offset and - 116dBc/Hz at 1MHz offset from a 2.5GHz carrier. At a supply voltage of 3V, the VCO core consumes 8mA. To our knowledge,this is the first differential cross-coupled VCO in SiGe BiCMOS technology in China. 展开更多
关键词 SiGe BiCMOS VCO INDUCTANCE phase noise
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An Accurate 1.08GHz CMOS LC Voltage-Controlled Oscillator 被引量:1
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作者 唐长文 何捷 +1 位作者 菅洪彦 闵昊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第5期867-872,共6页
An accurate 1.08GHz CMOS LC voltage-controlled oscillator is implemented in a 0.35μm standard 2P4M CMOS process.A new convenient method of calculating oscillator period is presented.With this period calculation tech... An accurate 1.08GHz CMOS LC voltage-controlled oscillator is implemented in a 0.35μm standard 2P4M CMOS process.A new convenient method of calculating oscillator period is presented.With this period calculation technique,the frequency tuning curves agree well with the experiment.At a 3.3V supply,the LC-VCO measures a phase noise of -82.2dBc/Hz at a 10kHz frequency offset while dissipating 3.1mA current.The chip size is 0.86mm×0.82mm. 展开更多
关键词 MOS varactor LC tank voltage-controlled oscillator oscillator tuning curve
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A Compact Ka-Band PHEMT MMIC Voltage Controlled Oscillator
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作者 余稳 孙晓玮 +1 位作者 钱蓉 张义门 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第6期1111-1115,共5页
A compact Ka-band monolithic microwave integrated circuit(MMIC) voltage controlled oscillator (VCO) with wide tuning range and high output power,which is based on GaAs PHEMT process,is presented.A method is introduced... A compact Ka-band monolithic microwave integrated circuit(MMIC) voltage controlled oscillator (VCO) with wide tuning range and high output power,which is based on GaAs PHEMT process,is presented.A method is introduced to reduce the chip size and to increase the bandwidth of operation.The procedure to design a MMIC VCO is also described here.The measured oscillating frequency of the MMIC VCO is 36±1.2GHz and the output power is 10±1dBm.The fabricated MMIC chip size is 1.3mm×1.0mm. 展开更多
关键词 VCO MMIC KA-BAND active-biasing PHEMT
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Gate Annealing of an Enhancement-Mode InGaP/AlGaAs/InGaAs PHEMT
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作者 黎明 张海英 +3 位作者 徐静波 李潇 刘亮 付晓君 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第8期1487-1490,共4页
For enhancement-mode InGaP/A1GaAs/InGaAs PHEMTs,gate annealing is conducted between gate structures of Ti/Pt/Au and Pt/Ti/Pt/Au. Comparison is made after thermal annealing and an optimum annealing process is ob- taine... For enhancement-mode InGaP/A1GaAs/InGaAs PHEMTs,gate annealing is conducted between gate structures of Ti/Pt/Au and Pt/Ti/Pt/Au. Comparison is made after thermal annealing and an optimum annealing process is ob- tained. Using the structure of Ti/Pt/Au, about a 200mV positive shift of threshold voltage is achieved by thermal annea- ling at 320℃ for 40min in N2 ambient. Finally, a stable and consistent enhancement-mode PHEMT is produced successfully with higher threshold voltage. 展开更多
关键词 ENHANCEMENT-MODE InGaP/A1GaAs/InGaAs PHEMT ANNEAL threshold voltage ring oscillator
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Theoretical Research on Electrorheological Isolator
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作者 张少华 李美艳 《Journal of Beijing Institute of Technology》 EI CAS 2001年第4期349-355,共7页
A new type of isolator, the electrorheology (ER) isolator, is mainly described. Through theoretical analysis, a simplified physical model is established under some hypotheses and a series of motion equations are deduc... A new type of isolator, the electrorheology (ER) isolator, is mainly described. Through theoretical analysis, a simplified physical model is established under some hypotheses and a series of motion equations are deduced. According to the transmissibility curve simulation under different electric field strengths, the main factors influencing ER isolator’s working properties have been ascertained. Finally, it proves that ER isolator works well in both low and high frequency zones, it can decrease the force transmitted and enlarge the isolation frequency domain efficiently. 展开更多
关键词 ELECTRORHEOLOGY ISOLATOR variable damping active-isolating
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Test and analysis of dynamic compaction vibration based on piezoelectric sensor
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作者 段伟 韩云山 +2 位作者 董彦莉 秦伟华 吴晗 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第2期116-122,共7页
The paper takes a new campus project site of Shanxi university town for example, tests the influence of dynamic com- paction vibration and vibration isolation effect of isolation trench on this ground, and compares th... The paper takes a new campus project site of Shanxi university town for example, tests the influence of dynamic com- paction vibration and vibration isolation effect of isolation trench on this ground, and compares the influences of the dynamic compaction vibration on surrounding buildings with isolation trench and without it. Furthermore, the attenuation law of dy- namic compaction vibration in fill foundation of the loess area under different tamping energy and how to determine safe distance of dynamic compaction construction are studied. And then the quantitative relationship between acceleration and vibration source in new campus project site is presented. We derive the evaluation method that dynamic compaction construction affects adjacent buildings by contrasting with the existing standards and norms. The monitoring results show that isolation trench makes the amplitude attenuation of the horizontal velocity of dynamic compaction vibration reach above 75%, and the safe dis- tance be 30 m under the tamping energy of 6 000 kN · m. Therefore, isolation trench is better for vibration reduction under dynamic compaction construction. 展开更多
关键词 dynamic compaction VIBRATION safety distance isolation trench piezoelectric sensor
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A NOVEL PHASE SHIFTED ZERO VOLTAGE SWITCHED PWM CONVERTER
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作者 阮新波 严仰光 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期33-40,共8页
Phase shifted converter realizes zero voltage switching (ZVS) with the use of leakage inductance of the main transformer, however, the realization of ZVS for lagging bridge leg is difficult. This paper proposes a c... Phase shifted converter realizes zero voltage switching (ZVS) with the use of leakage inductance of the main transformer, however, the realization of ZVS for lagging bridge leg is difficult. This paper proposes a current enhanced principle, and based on the principle, a novel phase shifted converter is proposed, which adds an auxi liary resonant net to the conventional full bridge converter to help the lagging bridge leg to realize ZVS. The principle and the design of the novel converter are analyzed, and the simulational and experimental results verify the principle. 展开更多
关键词 zero voltage switching resonant converter SIMULATION
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A 2.4GHz CMOS Quadrature Voltage-Controlled Oscillator Based on Symmetrical Spiral Inductors and Differential Diodes 被引量:2
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作者 池保勇 石秉学 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第2期131-135,共5页
A voltage controlled oscillator (VCO) which can generate 2 4GHz quadrature local oscillating (LO) signals is reported.It combines a LC VCO,realized by on chip symmetrical spiral inductors and differential diodes,an... A voltage controlled oscillator (VCO) which can generate 2 4GHz quadrature local oscillating (LO) signals is reported.It combines a LC VCO,realized by on chip symmetrical spiral inductors and differential diodes,and a two stage ring VCO.The principle of this VCO is demonstrated and further the phase noise is discussed in detail.The fabrication of prototype is demonstrated using 0 25μm single poly five metal N well salicide CMOS digital process.The reports show that the novel VCO is can generate quadrature LO signals with a tuning range of more than 300MHz as well as the phase noise--104 33dBc/Hz at 600KHz offset at 2 41GHz (when measuring only one port of differential outputs).In addition,this VCO can work in low power supply voltage and dissipate low power,thus it can be used in many integrated transceivers. 展开更多
关键词 quadrature VCO symmetrical spiral inductors differential diodes
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Optimization for Top DBR’s Reflectivity in RCE Photodectector
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作者 梁琨 陈弘达 +3 位作者 邓晖 杜云 唐君 吴荣汉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第4期409-413,共5页
The monolithic integration of vertical-cavity surface-emitting lasers (VCSEL) with photodetectors is very important in the application of free-space optical interconnects.Theoretical and experimental results on the re... The monolithic integration of vertical-cavity surface-emitting lasers (VCSEL) with photodetectors is very important in the application of free-space optical interconnects.Theoretical and experimental results on the resonant-cavity-enhanced (RCE) photodetector with VCSEL Structure are presented.The compatible requirement in input mirror reflectivity between the VCSEL and the RCE detector is achieved by precisely etching the top mirror.In this way,the RCE detector with relatively high quantum efficiency and necessary optical bandwidth has been obtained.[KH8/9D] 展开更多
关键词 vertical-cavity surface-emitting laser resonant-cavity-enhanced photodetector distributed Bragg reflector free-space optical interconnects
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Electrorheological Fluid and Its Application in Vibration Control
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作者 魏宸官 傅曌 《Journal of Beijing Institute of Technology》 EI CAS 1994年第1期98+91-98,共9页
This paper deals with the application of electrorheological fluid (ERF) in shock absorbers. Such shock absorbers (ERF shock absorbers) whose damping force is controlled Continuously and promptly through electric singn... This paper deals with the application of electrorheological fluid (ERF) in shock absorbers. Such shock absorbers (ERF shock absorbers) whose damping force is controlled Continuously and promptly through electric singnals, can be used in many kinds of mechanical equipment for vibration control. Typical structures of ERF shock absorbers are described and requirements for the ERF employed in shock absorbers are discussed. A new kind of shock absorber and its control system are presented and test results of the ERF shock absorber are given. 展开更多
关键词 shock absorber vibration/electrorhelolgical fluid
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