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锁相频率合成功率源与晶体介质谐振腔匹配网络
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作者 何洁 余东 +1 位作者 余伟 余冠河 《江苏大学学报(自然科学版)》 EI CAS 2002年第4期80-83,共4页
论述了锁模激光的调制器晶体谐振腔与锁相频率合成功率源匹配网络的实现 笔者经过深入研究 ,提出锁模激光的调制器晶体谐振腔非线性特性 并根据这一论断选择新的器件、网络电路 ,精心调制完成了难于实现的匹配 。
关键词 晶体介质谐振腔 锁模激光器 锁相频率合成功率 匹配 非线性 超大规模集成电路
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提高配电网合环计算成功率的方法
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作者 陈小娅 《新疆电力技术》 2012年第3期18-19,共2页
2009年乌鲁木齐电业局正式开展10kV配电网线路合环倒负荷试验,希望实现配电网不停电倒负荷,提高10kV配电网线路的供电质量,但合环倒负荷试验成功次数不多,仍无法大范围推广。通过对配电网合环等值模型的分析计算,提出将220kV电网等值模... 2009年乌鲁木齐电业局正式开展10kV配电网线路合环倒负荷试验,希望实现配电网不停电倒负荷,提高10kV配电网线路的供电质量,但合环倒负荷试验成功次数不多,仍无法大范围推广。通过对配电网合环等值模型的分析计算,提出将220kV电网等值模型进行改进,建立动态数学模型的方案,从而提高理论合环成功率。 展开更多
关键词 配电网 环到负荷 电网等值模型 成功率
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轿车底盘整体合装成功概率计算与误差分布模型
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作者 潘铁民 张顺琦 +2 位作者 董亚洲 孙建男 李晔 《汽车实用技术》 2023年第14期149-156,共8页
底盘盒装是整车装配关键环节,合装部件的形位公差决定合装成功率和成本。文章首先描述了合装误差概率的物理模型,然后运用尺寸链理论将其抽象为一个适当简化的合装数学模型,对合装成功率进行了公式推导和概率计算。最终在相关工装设备... 底盘盒装是整车装配关键环节,合装部件的形位公差决定合装成功率和成本。文章首先描述了合装误差概率的物理模型,然后运用尺寸链理论将其抽象为一个适当简化的合装数学模型,对合装成功率进行了公式推导和概率计算。最终在相关工装设备的公差、精度要求条件下得出理论上99.986%的成功概率,相比于实际值较大,经分析考虑到模型经适度简化且有假设条件此差异符合预期。该模型已广泛运用于多条标准化多平台汽车混合装配线。 展开更多
关键词 底盘整体 成功率 尺寸链 形位公差 正态分布 贝叶斯定理
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大腔体人造金刚石合成工艺的研究 被引量:2
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作者 李飞跃 李启泉 《地质与勘探》 CAS CSCD 北大核心 2001年第6期94-96,共3页
分析了我国现阶段金刚石的合成工艺———2 3mm腔体工艺的基础上 ,利用变功率合成技术和瓶颈效应后改变组装方式 ,使腔体内的物量比合理化 ,以达到腔体内合成温度和压力均匀 ,控制金刚石的生长速度 ,在较低的合成压力和合成功率下 ,在... 分析了我国现阶段金刚石的合成工艺———2 3mm腔体工艺的基础上 ,利用变功率合成技术和瓶颈效应后改变组装方式 ,使腔体内的物量比合理化 ,以达到腔体内合成温度和压力均匀 ,控制金刚石的生长速度 ,在较低的合成压力和合成功率下 ,在 2 8.5mm腔体和 31mm腔体上 。 展开更多
关键词 瓶颈效应 成工艺 人造金刚石 腔体 成压力 合成功率
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汽车底盘合装工位安装和理论基础研究 被引量:1
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作者 董亚洲 李晔 卢涛 《中国设备工程》 2019年第12期183-184,共2页
汽车主机厂ZP7的产量是由前期的规划决定的,除此之外,还有一个至关重要的影响因素,那就是设备开动率。纵观整个汽车总装车间,底盘合装工位既是瓶颈工位又是最重要的工位,它的成功率造成的直接结果既是是否停线。
关键词 汽车 底盘 极值法 成功率
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AlGaN/GaN HEMTs Power Amplifier MIC with Power Combining at C-Band 被引量:1
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作者 姚小江 李宾 +8 位作者 陈延湖 陈小娟 魏珂 李诚瞻 罗卫军 王晓亮 刘丹 刘果果 刘新宇 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第4期514-517,共4页
A power amplifier MIC with power combining based on AlGaN/GaN HEMTs was fabricated and measured. The amplifier consists of four 10 × 120μm transistors. A Wilkinson splitters and combining were used to divide and... A power amplifier MIC with power combining based on AlGaN/GaN HEMTs was fabricated and measured. The amplifier consists of four 10 × 120μm transistors. A Wilkinson splitters and combining were used to divide and combine the power. By biasing the amplifier at VDS = 40V, IDS = 0.9A, a maximum CW output power of 41.4dBm with a maximum power added efficiency (PAE) of 32.54% and a power combine efficiency of 69% was achieved at 5.4GHz. 展开更多
关键词 AlGaN/GaN HEMTs power combining MIC power amplifiers
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地域网单节点通信中分布式干扰性能研究
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作者 刘正堂 吴文华 +1 位作者 薛寒 王军 《现代电子技术》 2013年第5期20-23,共4页
为了研究分布式干扰在地域网通信中的性能,对地域网的结构特点进行分析,并给出了地域网的干扰策略;根据干扰策略,对地域网单节点通信中分布式干扰的合成功率以及干扰效果进行了研究,并仿真分析了分布式干扰的合成功率、干扰机数量、布... 为了研究分布式干扰在地域网通信中的性能,对地域网的结构特点进行分析,并给出了地域网的干扰策略;根据干扰策略,对地域网单节点通信中分布式干扰的合成功率以及干扰效果进行了研究,并仿真分析了分布式干扰的合成功率、干扰机数量、布阵方式以及干扰距离对地域网单节点通信性能的影响,仿真结果表明,干扰机数量、布阵方式及干扰距离均会对分布式干扰的性能产生影响。 展开更多
关键词 地域网 分布式干扰 扩频通信 合成功率 误码率
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分布式干扰对扩频接力通信干扰效果分析 被引量:1
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作者 刘正堂 薛寒 +1 位作者 王军 马光圆 《火力与指挥控制》 CSCD 北大核心 2013年第12期92-95,共4页
分析了分布式干扰相比于传统大功率干扰的距离优和数量优势。针对扩频接力通信系统,重点研究了分布式干扰的数量、干扰方式对通信性能的影响,并对理论结果进行了仿真分析,为分布式干扰机的研制与应用提供了参考。
关键词 分布式干扰 扩频接力通信 合成功率 误码率
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A4~12GHz Wideband Balanced MIC Power Amplifier 被引量:1
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作者 姚小江 李滨 +2 位作者 刘新宇 陈中子 陈晓娟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1868-1871,共4页
A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz cente... A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz center frequency with an associated gain of 8.5dB and a gain flatness of + /- 0.6dB in the 4-12GHz frequency range. 展开更多
关键词 WIDEBAND Lange coupler microwave integrated circuit balanced power amplifiers
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微波问题中的天线设计
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作者 马宇薪 胡立夫 +1 位作者 李成焱 卜虎 《中国科技信息》 2020年第24期60-62,共3页
无线网络如今正在飞速地发展,实体线路已经不能满足用户的要求,运营商正在各个地区各种地形上建立高质量的以微波接入为主的通讯基站,本文探讨并解决微波问题中的天线设计问题,得到一定合成功率的输入功率,利用MATLAB进行模拟仿真,使用... 无线网络如今正在飞速地发展,实体线路已经不能满足用户的要求,运营商正在各个地区各种地形上建立高质量的以微波接入为主的通讯基站,本文探讨并解决微波问题中的天线设计问题,得到一定合成功率的输入功率,利用MATLAB进行模拟仿真,使用遗传算法来实现对旁瓣电平的降低,并选择性通过关闭某些通道,解决资源分配问题。 展开更多
关键词 天线设计 旁瓣电平 通讯基站 无线网络 微波接入 模拟仿真 合成功率 遗传算法
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An 8GHz Internally Matched AlGaN/GaN HEMT Power Amplifier with RC Stability Network
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作者 曾轩 陈晓娟 +8 位作者 刘果果 袁婷婷 陈中子 张辉 王亮 李诚瞻 庞磊 刘新宇 刘键 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第8期1445-1448,共4页
8GHz 20W internally matched A1GaN/GaN HEMTs have been developed. The input and output matching net- works are realised with microstrip lines on a 0. 381mm thick alumina substrate. To improve the stability factor K of ... 8GHz 20W internally matched A1GaN/GaN HEMTs have been developed. The input and output matching net- works are realised with microstrip lines on a 0. 381mm thick alumina substrate. To improve the stability factor K of the device, a lossy RC network is used at the input of the device. The developed internally matched power amplifier module exhibits 43dBm (20W) power output with a 7.3dB linear gain,38.1% PAIE,and combined power efficiency of 70.6% at 8GHz. 展开更多
关键词 AlGaN/GaN HEMTs internally match power combining power amplifier
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POWER OPTIMIZATION ALGORITHM BASED ON XNOR/OR LOGIC 被引量:1
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作者 Wang Pengjun Lu Jingang +1 位作者 Xu Jian Dai Jing 《Journal of Electronics(China)》 2009年第1期138-144,共7页
Based on the investigation of the XNOR/OR logical expression and the propagation al- gorithm of signal probability, a low power synthesis algorithm based on the XNOR/OR logic is pro- posed in this paper. The proposed ... Based on the investigation of the XNOR/OR logical expression and the propagation al- gorithm of signal probability, a low power synthesis algorithm based on the XNOR/OR logic is pro- posed in this paper. The proposed algorithm has been implemented with C language. Fourteen Mi- croelectronics Center North Carolina (MCNC) benchmarks are tested, and the results show that the proposed algorithm not only significantly reduces the average power consumption up to 27% without area and delay compensations, but also makes the runtime shorter. 展开更多
关键词 Reed-Muller Logic synthesis XNOR/OR Low power synthesis
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Research on Program-controlled Power Source Based on DDS
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作者 杨学蔚 公茂法 +2 位作者 公政 梁育雷 李保勇 《Journal of Measurement Science and Instrumentation》 CAS 2011年第1期75-77,共3页
Direct Digital Synthesis (DDS) chip was used in the design of program controlled power source in this paper. With the accurate control of Dual DDS chips by Micro Controller Unit (MCU), illter and power amplifier, ... Direct Digital Synthesis (DDS) chip was used in the design of program controlled power source in this paper. With the accurate control of Dual DDS chips by Micro Controller Unit (MCU), illter and power amplifier, this power source can generate voltage and corrent output with variable frequency, amplitude and phase. There are several advantages of this power source such as high power, high accuiracy, output stable, light and conveaient. 展开更多
关键词 DDS phase control power source program-controlled
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A new broadband differential phase shifter fabricated using a novel CRLH structure
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作者 ZOU Yong-zhuo LIN Zhi-li +2 位作者 LING Ti YAO Jun HE Sailing 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第10期1568-1572,共5页
Broadband phase shifters are mostly proposed and fabricated based on the scheme proposed by Shiffman, which uses a coupled line with far ends connected together and a uniform transmission line to give a differential p... Broadband phase shifters are mostly proposed and fabricated based on the scheme proposed by Shiffman, which uses a coupled line with far ends connected together and a uniform transmission line to give a differential phase shift. Based on the unique dispersion property of the composite right/left-handed (CRLH) metamaterial structure, a new configuration is presented in this paper for fabricating the broadband differential phase shifter, which employs a novel CRLH metamaterial structure as one of the differential phase-shift arms, instead of the conventional coupled line. The new circuit can achieve a phase shift of 90° in an operational bandwidth as broad as one octave and its phase deviations are quite small. An original design of the novel broadband phase shifter is presented, in which the artificial CRLH structure was implemented by microstrip quasi-lumped elements. Both the simulated and measured results of the 90° broadband differential phase shifter are presented. 展开更多
关键词 BROADBAND Differential phase shifter Composite right/left-handed (CRLH) metamaterial structure Quasi-lumpedelements
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Effect of Microwave Power on the Zn2SnO4 Synthesis and Its Use for Photodegradation of Phenol
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作者 Edson Luiz Foletto Marcio Antonio Mazutti +5 位作者 Adriano Cancelier Erico Marion de Moraes Flores Edson Irineu Muller Leticia Severo Fagundes Pereira Osvaldo Chiavone-Filho Andre Gundel 《Journal of Chemistry and Chemical Engineering》 2014年第8期794-799,共6页
Spinel structure Zn2SnO4 was successfully synthesized by microwave-assisted hydrothermal process. The effects of the microwave power on the formation and physical properties of the Zn2SnO4 particles are discussed. The... Spinel structure Zn2SnO4 was successfully synthesized by microwave-assisted hydrothermal process. The effects of the microwave power on the formation and physical properties of the Zn2SnO4 particles are discussed. The products were characterized by X-ray diffraction, atomic force microscopy, infrared spectroscopy, and N2 adsorption. The results indicated that the microwave power had important influence on the formation of the spinel phase. The results also revealed that the physical properties of Zn2SnO4 particles did not change with the increase of the microwave power above 600 W, with 20 min of reaction time. Furthermore, the photocatalytic activity of the Zn2SnO4 particles for the phenol degradation under sunlight was also investigated. 展开更多
关键词 Zn2SnO4 zinc stannate SYNTHESIS MICROWAVE porous material photocatalysis.
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The effect of transition metal ions (M^(2+)=Mn^(2+),Ni^(2+),Co^(2+),Cu^(2+)) on the chemical synthesis polyaniline as counter electrodes in dye-sensitized solar cells 被引量:2
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作者 Kezhong Wu Lei Chen +2 位作者 Weizhen Cui Bei Ruan Mingxing Wu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第5期671-675,共5页
The effect of transition metal ions(M^(2+)=Mn^(2+),Ni^(2+),Co^(2+),Cu^(2+)) on the chemical synthesis of polyaniline(PANI) used as a platinum-free counter electrode(CE) in dye-sensitized solar cells(DSSCs) was investi... The effect of transition metal ions(M^(2+)=Mn^(2+),Ni^(2+),Co^(2+),Cu^(2+)) on the chemical synthesis of polyaniline(PANI) used as a platinum-free counter electrode(CE) in dye-sensitized solar cells(DSSCs) was investigated.PANI was synthesized by co-polymerization of aniline in the presence of different transition metal ions by using potassium dichromate in acidic medium. It was found that the ion doping of PANI showed a certain catalytic activity for the regeneration of traditional iodide/triiodide(I^-/I_3^-) redox couples. The power conversion efficiency(η) of PANI CEs doped with Mn^(2+),Ni^(2+),Co^(2+) (4.41%, 2.36% and 2.10%, respectively) were higher than 1.94%, the value measured for PANI CE without doping. Doping with Cu^(2+)decreased the power conversion efficiency of PANI CE(PANI-Cu^(2+) η = 1.41%). The electrical properties of the PANI, PANI-Ni^(2+), PANI-Co^(2+),PANI-Mn^(2+) and PANI-Cu^(2+) were studied by cyclic voltammetry(CV), impedance(EIS), and Tafel polarization curve. The experimental results confirmed that PANI was affected by the doping of different transition metal ions(M^(2+)=Mn^(2+),Ni^(2+),Co^(2+),Cu^(2+)). These results indicate a potential application of ion doped PANI as counter electrode in cost-effective DSSCs. 展开更多
关键词 Dye-sensitized solar cell Counter electrode Polyaniline Transition metal ion Power conversion efficiency
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57孔径光纤激光相控阵自适应光学系统实现经2km大气传输的目标在回路相干合成 被引量:7
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作者 李枫 邹凡 +10 位作者 姜佳丽 左竞 周鑫 李自强 刘家盈 潘丽康 潘姿廷 杨旭 黄冠 耿超 李新阳 《中国激光》 EI CAS CSCD 北大核心 2022年第6期193-195,共3页
当前,光纤相控阵体制的激光相干合成技术在合成路数和合成功率方面都取得了突破,根据公开文献报道,最多合成路数和最高合成功率已分别达到107路和20 kW。但是,该技术离实际的激光传输应用还有一定差距,必须要解决等效大口径问题、共形... 当前,光纤相控阵体制的激光相干合成技术在合成路数和合成功率方面都取得了突破,根据公开文献报道,最多合成路数和最高合成功率已分别达到107路和20 kW。但是,该技术离实际的激光传输应用还有一定差距,必须要解决等效大口径问题、共形发射问题、湍流补偿问题以及实现轻量化和低成本的问题。光纤激光相控阵自适应光学(AO)系统通过对子孔径波前活塞和倾斜相位的主动操控和闭环补偿有望解决以上问题,实现阵列激光的高效传输及其在目标处的相干合成,是近期该领域的研究热点。 展开更多
关键词 相干 光纤激光相控阵 大气传输 激光传输 目标在回路 自适应光学系统 合成功率 相控阵体制
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Design of remote ultrasonic signal generating system based on Kinetis60 and AD9951
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作者 HUO Liang-sheng LI Cheng-long 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第4期396-404,共9页
A kind of remote ultrasonic generating system is designed in this paper.Microcontroller unit(MCU)Kinetis60and direct digital synthesizer(DDS)AD9951constitute the core section of this ultrasonic generating terminal in ... A kind of remote ultrasonic generating system is designed in this paper.Microcontroller unit(MCU)Kinetis60and direct digital synthesizer(DDS)AD9951constitute the core section of this ultrasonic generating terminal in this system.A friendly and easy-operating host computer software is contrived to control the terminal to generate sinusoidal,rectangular and triangular waveform with variable frequency,amplitude and phase through ZigBee wireless transmission protocol.In order to enhance the practical driving ability,this system also includes power amplifier circuit and transformer matching design,which enable the ultrasonic generating terminal to output enough power for applying to different types of ultrasonic energy convertors.Through experimental verification,the host computer can precisely and swiftly control the ultrasonic generating terminal to generate the above three waveforms with variable wave elements.Oscilloscope is used to verify the terminal output performance of this remote system. 展开更多
关键词 ULTRASONIC direct digital synthesizer (DDS) microcontroller Kinetis60 power amplification toroidal transformer
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An InGaP/GaAs HBT MIC Power Amplifier with Power Combining at the X-Band
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作者 陈延湖 申华军 +4 位作者 王显泰 陈高鹏 刘新宇 袁东风 王祖强 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第11期2098-2100,共3页
A MIC power amplifier with power combining based on InGaP/GaAs HBT is developed and measured for the application of the latest high power amplifier stage of the X-band. A novel InGaP/GaAs HBT power transistor with an ... A MIC power amplifier with power combining based on InGaP/GaAs HBT is developed and measured for the application of the latest high power amplifier stage of the X-band. A novel InGaP/GaAs HBT power transistor with an on-chip RC stabilization network is used as the power combing cell to improve the stability of the circuit. A compact mi- crostripe line parallel matching network is used to divide and combine the power. By biasing the amplifier at class AB: Vc= 7V, Ic = 230mA,a maximum CW stabile output power of 28.9dBm and a power combine efficiency of 80% are achieved at 8. 1GHz. 展开更多
关键词 InGaP/GaAs HBT power combining MIC power amplifiers
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