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某紧凑型SUV前门内板限位器处焊点开裂分析
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作者 张杰林 李乃鹏 覃丰宁 《企业科技与发展》 2019年第7期102-104,共3页
文章对某紧凑型SUV前门内板限位器处焊点在顾客大力甩门的工况下出现开裂进行了分析,分析内容包括汽车车门的使用工况,车门内板在极限使用工况下故障模式,车门内板限位器处焊点在极限工况下受力标定,原车门结构焊点应力的CAE分析,新方... 文章对某紧凑型SUV前门内板限位器处焊点在顾客大力甩门的工况下出现开裂进行了分析,分析内容包括汽车车门的使用工况,车门内板在极限使用工况下故障模式,车门内板限位器处焊点在极限工况下受力标定,原车门结构焊点应力的CAE分析,新方案的焊点应力CAE分析,CAE分析验证等,经过系统的分析总结,避免了后续车型车门内板限位器处焊点的开裂问题,提高了车门的可靠性,缩短了汽车的开发时间。 展开更多
关键词 内板 限位器处焊点 开裂 CAE分析 结构胶
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微处理器电源监视集成电路TL7705AC
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作者 陆晓 《水利水文自动化》 1992年第3期36-38,共3页
一、前言每一个微处理器系统都需要一个复位电路,以保证上电时,整个系统处于—个正确的初始状态。通常使用RC电路作为上电复位电路,但此电路存在着不少无法避免的缺点。为了克服这些缺点,提高系统的可靠性,美国德州仪器公司(TT)推出了... 一、前言每一个微处理器系统都需要一个复位电路,以保证上电时,整个系统处于—个正确的初始状态。通常使用RC电路作为上电复位电路,但此电路存在着不少无法避免的缺点。为了克服这些缺点,提高系统的可靠性,美国德州仪器公司(TT)推出了一系列的电源电路,它们都能在电源上电时产生复位信号,平时监视电源电压,当电源掉电或降低时,产生复位信号,直至电源恢复正常。在这一系列集成电路中,TL7705AC具有外围元件最少,温度范围最宽,驱动能力最强等特点。 展开更多
关键词 电源 集成电路 监视
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简易“处母羊开膣器”的制做
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作者 屈中泽 《黑龙江畜牧兽医》 CAS 北大核心 2002年第12期64-64,共1页
关键词 人工授精 母羊开Qi 制做
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徒手压迫与Perclose缝合器对介入术后股动脉假性动脉瘤形成的比较 被引量:1
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作者 周国伟 温沁竹 +6 位作者 孙宝贵 张建军 金炜 张国兵 王毅 徐浩 储光 《上海医学》 CAS CSCD 北大核心 2007年第S1期31-31,共1页
目的评价徒手压迫与Perclose血管缝合器处理对股动脉介入术后股动脉假性动脉瘤(PSA)发生率的影响。方法回顾性分析2000年3月至2006年7月共3 586例经股动脉介入患者的资料,根据术后处理穿刺伤口方法的不同分为徒手压迫组(3 060例)和Percl... 目的评价徒手压迫与Perclose血管缝合器处理对股动脉介入术后股动脉假性动脉瘤(PSA)发生率的影响。方法回顾性分析2000年3月至2006年7月共3 586例经股动脉介入患者的资料,根据术后处理穿刺伤口方法的不同分为徒手压迫组(3 060例)和Perclose血管缝合器组(526例)。比较两组患者术后形成股动脉假性动脉瘤(PSA)的概率及其预后。结果徒手压迫组的股动脉PSA发生率为1.3%(41/3 060例),Perclose血管缝合器组为0.8%(4/526例),两组的差异无统计学意义(P=0.20)。徒手压迫组41例股动脉PSA患者均采用改良超声引导下徒手压迫法,压迫30-150 min,成功闭合37例,总成功率为90.2%,均无复发;再压迫失败者中3例转外科行PSA修补术,1例拒绝手术出院随访。Perclose血管缝合器组4例股动脉PSA患者采用徒手压迫法均将PSA闭合,无复发。结论Perclose缝合器不能明显降低股动脉PSA的发生率,该器械尚有待于进一步改进,提高股动脉穿刺技术可能降低PSA的发生率。 展开更多
关键词 缝合 PERCLOSE 介入术 假性动脉瘤 血管缝合 压迫法 总成功率 穿刺伤 器处 理对
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振动管式流体密度传感器研究 被引量:5
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作者 谭宝海 鞠晓东 《测井技术》 CAS CSCD 2004年第4期341-343,共3页
介绍一种应用于井下自由衰减振动式流体密度传感器。传感器基于管内流体密度与管自由衰减振动周期的非线性关系理论 ,采用独特的电磁激振和动圈检振的激、检振方式 ,以PIC16F87X微处理器为核心 ,配合少量模拟电路完成流体密度的测量 ,... 介绍一种应用于井下自由衰减振动式流体密度传感器。传感器基于管内流体密度与管自由衰减振动周期的非线性关系理论 ,采用独特的电磁激振和动圈检振的激、检振方式 ,以PIC16F87X微处理器为核心 ,配合少量模拟电路完成流体密度的测量 ,并提供曼彻斯特编码输出 /输入和模拟输出方式与外界进行接口。实验结果表明 ,流体密度与振动管的自由衰减振动周期成近似线性的函数关系 ,其非线性程度是由传感器的形状和材料参数决定的 ;随着振动管内流体密度的增加 ,其振动管自由衰减的振动周期也增加。这种机电一体化的流体密度传感器在井下应用时必须进行井场刻度以及温度和压力的校正。 展开更多
关键词 生产测井 流体密度 传感
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三次拆解平地机变速器引发的思考
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作者 葛云志 《工程机械与维修》 2015年第5期78-79,共2页
1台配装柳州ZF6WG200型变速器的徐工215型平地机,当挂上前进Ⅱ、Ⅳ挡,热机时能行走、冷机时不能行走,起步出现向前猛闯现象,平地作业时无力。1.首次拆解将变速器解体后。发现K2离合器摩擦片有磨损和变形现象。K2离合器正是控制Ⅲ、Ⅳ挡... 1台配装柳州ZF6WG200型变速器的徐工215型平地机,当挂上前进Ⅱ、Ⅳ挡,热机时能行走、冷机时不能行走,起步出现向前猛闯现象,平地作业时无力。1.首次拆解将变速器解体后。发现K2离合器摩擦片有磨损和变形现象。K2离合器正是控制Ⅲ、Ⅳ挡的离合器,该变速器各挡位与离合器关系如附表所示。更换了摩擦片和密封件,装复后测试变速控制系统压力正常,且作业时驱动力明显增大。但操作时发现前进Ⅱ、Ⅲ、Ⅳ挡又不工作,其余挡位正常。由于此故障是维修后出现的,初步判定是维修时装配不当造成。 展开更多
关键词 平地机 离合摩擦片 压力正常 徐工 配装 密封件 变形现象 换挡控制 器处 充气试验
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液力自动变速器的控制功能研究
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作者 孙炜 《汽车与配件》 2015年第30期52-53,共2页
汽车自动变速器技术正突飞猛进的发展,国外90%的商用车都配有自动变速器,国内商用车市场刚刚起步,发展空间很大。目前,随着智能控制技术的发展,变速器已经由手动时代进入到了自动变速器时代。自动变速器主要有电控机械自动变速器(AMT-Au... 汽车自动变速器技术正突飞猛进的发展,国外90%的商用车都配有自动变速器,国内商用车市场刚刚起步,发展空间很大。目前,随着智能控制技术的发展,变速器已经由手动时代进入到了自动变速器时代。自动变速器主要有电控机械自动变速器(AMT-Automated Mechanical Transmission)、液力机械自动变速器(AT-Automatic Transmission)、无级自动变速器(CVT-Continuously Variable Transmission)及双离合自动变速器(DCT-Dual Clutch Transmission)4种类型。目前,在商用车领域,由于自身性能限制,以使用AMT和AT为主。AT是目前汽车上应用最为广泛的一种自动变速器。 展开更多
关键词 自动变速 商用车 智能控制技术 缓速 性能限制 前进档 乘用车 输出轴转速 大中型客车 器处
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Data processing method for aerial testing of rotating accelerometer gravity gradiometer
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作者 QIAN Xuewu TANG Hailiang 《中国惯性技术学报》 EI CSCD 北大核心 2024年第8期743-752,共10页
A novel method for noise removal from the rotating accelerometer gravity gradiometer(MAGG)is presented.It introduces a head-to-tail data expansion technique based on the zero-phase filtering principle.A scheme for det... A novel method for noise removal from the rotating accelerometer gravity gradiometer(MAGG)is presented.It introduces a head-to-tail data expansion technique based on the zero-phase filtering principle.A scheme for determining band-pass filter parameters based on signal-to-noise ratio gain,smoothness index,and cross-correlation coefficient is designed using the Chebyshev optimal consistent approximation theory.Additionally,a wavelet denoising evaluation function is constructed,with the dmey wavelet basis function identified as most effective for processing gravity gradient data.The results of hard-in-the-loop simulation and prototype experiments show that the proposed processing method has shown a 14%improvement in the measurement variance of gravity gradient signals,and the measurement accuracy has reached within 4E,compared to other commonly used methods,which verifies that the proposed method effectively removes noise from the gradient signals,improved gravity gradiometry accuracy,and has certain technical insights for high-precision airborne gravity gradiometry. 展开更多
关键词 airborne gravity gradiometer data processing band-passing filter evaluation function
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机载布撒器中SINS/GPS导航计算机的设计 被引量:1
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作者 徐际威 单家元 王正杰 《弹箭与制导学报》 CSCD 北大核心 2005年第SD期922-924,共3页
文中以布撒器的捷联惯导和 GPS 组合导航系统(SINS/GPS)为研究背景,介绍了以 TMS320VC33为核心处理器,实现多路导航数据实时采集,控制周期内导航数据的解算,GPS 导航数据实时校正,与主控机和遥测机等的数据交换的硬件平台设计过程。
关键词 数字信号(DSP) CPLD 捷联惯导和 GPS 组合导航(SINS/GPS)
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2.488 Gbit/s clock and data recovery circuit in 0.35 μm CMOS 被引量:1
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作者 王欢 王志功 +2 位作者 冯军 熊明珍 章丽 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期143-147,共5页
The design of a 2. 488 Gbit/s clock and data recovery (CDR) If for synchronous digital hierarchy (SDH) STM-16 receiver is described. Based on the injected phase-locked loop (IPLL) and D-flip flop architectures, ... The design of a 2. 488 Gbit/s clock and data recovery (CDR) If for synchronous digital hierarchy (SDH) STM-16 receiver is described. Based on the injected phase-locked loop (IPLL) and D-flip flop architectures, the CDR IC was implemented in a standard 0. 35 μan complementary metal-oxide-semiconductor (CMOS) technology. With 2^31 -1 pseudorandom bit sequences (PRBS) input, the sensitivity of data recovery circuit is less than 20 mV with 10^-12 bit error rate (BER). The recovered clock shows a root mean square (rms) jitter of 2. 8 ps and a phase noise of - 110 dBc/Hz at 100 kHz offset. The capture range of the circuit is larger than 40 MHz. With a 5 V supply, the circuit consumes 680 mW and the chip area is 1.49 mm × 1 mm. 展开更多
关键词 clock recovery data recovery phase-locked loop (PLL) PREPROCESSOR
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A New Cochlear Prosthetic System with an Implanted DSP 被引量:2
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作者 麦宋平 张春 +1 位作者 晁军 王志华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第9期1745-1752,共8页
This paper proposes a cochlear prosthetic system with an implanted digital signal processor (DSP). This system transmits voice-band signals with a low data rate through the wireless link, free of the data-rate limit... This paper proposes a cochlear prosthetic system with an implanted digital signal processor (DSP). This system transmits voice-band signals with a low data rate through the wireless link, free of the data-rate limitation and suitable for future development. By optimizing the speech processing algorithm and the DSP hardware design, the implanted DSP manages to execute the continuous interleaved sampling (CIS) algorithm at a clock frequency of 3MHz and a power consumption of only 1.91mW. With an analytic power-transmission efficiency of the wireless inductive link (40%), the power overhead caused by the implanted DSP is derived as 2.87roW,which is trivial when compared with the power consumption of existing cochlear prosthetic systems (tens of milliwatts). With the DSP implanted,this new system can.be easily developed into a fully implanted cochlear prosthesis. 展开更多
关键词 cochlear prosthesis low power algorithm optimization digital signal processor power-transmission efficiency
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A Low-Power-Consumption 9bit 10MS/s Pipeline ADC for CMOS Image Sensors 被引量:1
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作者 朱天成 姚素英 李斌桥 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1924-1929,共6页
A low-power-consumption 9bit 10MS/s pipeline ADC,used in a CMOS image sensor,is proposed. In the design, the decrease of power consumption is achieved by applying low-power-consumption and large-output-swing amplifier... A low-power-consumption 9bit 10MS/s pipeline ADC,used in a CMOS image sensor,is proposed. In the design, the decrease of power consumption is achieved by applying low-power-consumption and large-output-swing amplifiers with gain boost structure, and biasing all the cells with the same voltage bias source, which requires careful layout design and large capacitors. In addition,capacitor array DAC is also applied to reduce power consumption,and low threshold voltage MOS transistors are used to achieve a large signal processing range. The ADC was implemented in a 0.18μm 4M-1 P CMOS process,and the experimental results indicate that it consumes only 7mW, which is much less than general pipeline ADCs. The ADC was used in a 300000 pixels CMOS image sensor. 展开更多
关键词 pipeline ADC low power design CMOS image sensor large signal processing range
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Research on detection of lane based on machine vision 被引量:6
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作者 李旭 张为公 卞晓东 《Journal of Southeast University(English Edition)》 EI CAS 2004年第2期176-180,共5页
To prevent a vehicle from departing the lane in assistant or automatic steering, real-time vision-based detection of lane is studied. The system architecture, detecting principle and lane model are described. Then the... To prevent a vehicle from departing the lane in assistant or automatic steering, real-time vision-based detection of lane is studied. The system architecture, detecting principle and lane model are described. Then the detecting algorithm of the lane image is discussed in detail. In this algorithm, several proper sub-windows in one image are first selected as the processing regions. To every sub-window, by means of such steps as appropriate pre-processing, edge detection and Hough transform, etc., the lane description features are extracted. Experimental results reveal that this detection method is of good real-time, high recognition reliability and strong robustness, etc., which can provide the decision-making foundation for the following automatic or assistant steering to some extent. 展开更多
关键词 Charge coupled devices Computer vision Decision making Edge detection Hough transforms
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STUDY AND SIMULATION OF AN ACTIVATED SLUDGE TREATMENT FOR METHYL VIOLET WASTE WATER
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作者 张金利 宋宽秀 +1 位作者 王一平 闻建平 《Transactions of Tianjin University》 EI CAS 1998年第2期72-75,共4页
This paper researched a promising biological treatment of methyl violet waste water by methods of activated sludge.Effects of temperature and pH were studied on this process.Kinetic equation ... This paper researched a promising biological treatment of methyl violet waste water by methods of activated sludge.Effects of temperature and pH were studied on this process.Kinetic equation of the substrate biodegradation was investigated in the experimental range.It was studied and simulated that flow within the bubble region of this bioreactor according to the κ ε two fluid equation.Simulation results agree well with experimental data. 展开更多
关键词 bioreactor waste water treatment activated sludge
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Underground vibration signal detection and processing system based on LabWindows/CVI 被引量:1
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作者 刘培珍 夏湖培 姚金杰 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期57-62,共6页
In order to detect and process underground vibration signal, this paper presents a system with the combination of software and hardware. The hardware part consists of sensor, memory chips, USB, etc. , which is respons... In order to detect and process underground vibration signal, this paper presents a system with the combination of software and hardware. The hardware part consists of sensor, memory chips, USB, etc. , which is responsible for capturing original signals from sensors. The software part is a virtual oscilloscope based on LabWindows/CVI (C vitual instrument), which not only has the functions of traditional oscilloscope but also can analyze and process vibration signals in special ways. The experimental results show that the designed system is stable, reliable and easy to be operated, which can meet practical requirements. 展开更多
关键词 virtual instrument data processing and detection vibration signal LABWINDOWS/CVI
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MICROPROCESSOR BASED MODEL FOLLOWING ADAPTIVE CONTROL SYSTEM FOR CSIM DRIVES
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作者 张春明 左敦稳 王珉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期40+35-39,共6页
A model following adaptive control system for CSIM is presented in this paper. A dynamic mathematical model of slip control based system is obtained. With the help of model reducing technique, full order model is ... A model following adaptive control system for CSIM is presented in this paper. A dynamic mathematical model of slip control based system is obtained. With the help of model reducing technique, full order model is reduced to simplify the design without degrading much of the performance. Model following adaptive control laws in discrete form are derived. These laws satisfy the hyperstability condition for taking care of the load and machine parameter changes of the drive. A microprocessor 8098 is used to develop the speed controller. The implementation of the control system uses only available variables of the reference model and the controlled plant. Experimental results are given to demonstrate the good performance of the system. 展开更多
关键词 induction motors frequency converters microprocessors adaptive control model following
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A SMART COMPENSATION SYSTEM BASED ON MCA7707 PROCESSOR
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作者 赵敏 姚敏 颜彦 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第1期97-101,共5页
This paper presents a smart compensation system based on MCA7707 (a kind of signal processor). The li near errors and high order errors of a sensor (especially piezoresistive sensor) can be corrected by using this s... This paper presents a smart compensation system based on MCA7707 (a kind of signal processor). The li near errors and high order errors of a sensor (especially piezoresistive sensor) can be corrected by using this system. It can optimize the process of piezoresi stive sensor calibration and compensation, then, a total error factor within 0.2 % of the sensor′s repeatability errors is obtained. Data are recorded and coeff icients are determined automatically by this system, thus, the sensor compensati on is simplified greatly. For operating easily, a wizard compensation program is designed to correct every error and to get the optimum compensation. 展开更多
关键词 MCA7707 processor temp erature compensation piezoresistive sensor
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Research on Software Radio Fuze
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作者 黄忠华 崔占忠 +1 位作者 林森 栗苹 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期81-85,共5页
The functions and characteristics of software radio are discussed. Using techniques and method of software radio, the concept and advantages of a new kind of radio fuze, software radio fuze, are analysed. Several kind... The functions and characteristics of software radio are discussed. Using techniques and method of software radio, the concept and advantages of a new kind of radio fuze, software radio fuze, are analysed. Several kinds of hardware platform structures of the software radio fuze are studied and the key techniques are analysed. The software radio fuze will become the most promising radio fuze techniques in 21st century. 展开更多
关键词 software radio FUZE hardware platform digital signal processor(DSP)
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谈谈实现稳妥连挂
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作者 耿守忠 《铁道运输与经济》 1985年第4期17-18,共2页
安全、准确、迅速地完成调车任务,其中关键的一环,就是实现稳妥连挂,杜绝连挂作业中的撞车事故。因此,做为一名调车司机,研究稳妥连挂的理论和正确操纵机车的方法,是很有必要的。本文就如何实现稳妥连挂,谈一些粗浅的体会和看法。
关键词 缓冲容量 操纵机 撞车事故 东风型内燃机车 限制速度 千焦 板簧 器处 弹性连接 压缩状态
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Design and Development of the DTC Induction Motor Drive for Electric Vehicle
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作者 孙逢春 程夕明 《Journal of Beijing Institute of Technology》 EI CAS 2000年第4期415-421,共7页
The design and development of the traction controller for electric vehicle is introduced, which is based on the induction motor. This drive is developed by using a digital signal processor at low cost and carried out ... The design and development of the traction controller for electric vehicle is introduced, which is based on the induction motor. This drive is developed by using a digital signal processor at low cost and carried out with the module design concept of both software and hardware. Nevertheless, a scheme of the sensorless direct torque control is based on the developed hardware, of which the feasibility is tested by a trial program. Additionally, both the interface function of the drive hardware and the feasibility of its software are proved to be good by the trail programs. A test motor can run about 18?r/min by a variable frequency program with the space vector pulse width modulation technology, of which the torque is visible pulsatile. In this presentation, based on the theoretical approach, the sensorless torque control is to be studied and applied to electric vehicles, of which the quick, smooth and stable torque response is emphasized because it quite benefits improving the drive performance of electric vehicles. 展开更多
关键词 electric vehicle induction motor digital signal processor direct torque control
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