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晚号声中有宝石——读阮章竞《晚号集》中的两首叙事诗
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作者 曾镇南 《中国图书评论》 CSSCI 北大核心 2001年第11期35-37,共3页
关键词 阮章竞 《晚 叙事诗 艺术个性 当代文学研究
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多基因型种群品种多集新3号的选育和相关问题说明 被引量:7
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作者 徐超飞 李华军 李晓方 《中国稻米》 2014年第2期71-73,共3页
以第一个商业化的多基因型种群水稻品种多集新3号为例,从育种技术、种子生产和种子执法3个层面,澄清了人们对精准化多基因型种群品种所存在的一些疑惑问题,并分析了精准化多基因型种群育种对作物育种的价值和种业发展的意义。
关键词 多基因型种群 品种形态 种子生产 新3
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A new type of fiber Bragg grating based seismic geophone 被引量:6
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作者 陶果 张向林 +2 位作者 刘新茹 陈少华 刘统玉 《Applied Geophysics》 SCIE CSCD 2009年第1期84-92,104,共10页
Aimed at the poor performance of conventional geophones in exploration for deeper and complex targets, we present the principle and theoretical design of a new geophone based on the optical fiber Bragg grating (FBG)... Aimed at the poor performance of conventional geophones in exploration for deeper and complex targets, we present the principle and theoretical design of a new geophone based on the optical fiber Bragg grating (FBG) sensing technology. The important parameters such as response functions are calculated theoretically. Because of the advantages of FBG sensing technology, the new FBG geophone has a high dynamic range of 94dB at (10-200 Hz). This new generation of geophones will have wide use in seismic prospecting due to its higher sensitivity, lighter weight, and lower cost. 展开更多
关键词 oil exploration fiber optical sensor seismic data acquisition
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Design of high-speed signal acquisition system and analysis of signal integrity 被引量:1
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作者 姚琴琴 谢锐 +1 位作者 白茹 申玉玲 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期63-67,共5页
The device is used for the test on the fuze detonating time according to the initial velocity of the projectile and the altitude and speed of enemy aircraft flight. For the special requirements of the high-speed signa... The device is used for the test on the fuze detonating time according to the initial velocity of the projectile and the altitude and speed of enemy aircraft flight. For the special requirements of the high-speed signal acquisition in the process, the characteristics of the measured signal are analyzed. The system is investigated in chip selection, signal transmission, signal processing, signal storage, post-production PCB design, etc. The appropriate measures and solutions which affect the integrity and accuracy of the signal in each process are proposed. The rules for the layout of the device and wiring are made. The result show that the measurement values are accurate without loss of data. 展开更多
关键词 high-speed PCB simulation data acquisition signal integrity static storage
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Reservoir information extraction using a fractional Fourier transform and a smooth pseudo Wigner-Ville distribution 被引量:5
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作者 王祝文 王晓丽 +3 位作者 向旻 刘菁华 张雪昂 杨闯 《Applied Geophysics》 SCIE CSCD 2012年第4期391-400,494,495,共12页
Currently, it is difficult for people to express signal information simultaneously in the time and frequency domains when analyzing acoustic logging signals using a simple-time or frequency-domain method. It is diffic... Currently, it is difficult for people to express signal information simultaneously in the time and frequency domains when analyzing acoustic logging signals using a simple-time or frequency-domain method. It is difficult to use a single type of time-frequency analysis method, which affects the feasibility of acoustic logging signal analysis. In order to solve these problems, in this paper, a fractional Fourier transform and smooth pseudo Wigner Ville distribution (SPWD) were combined and used to analyze array acoustic logging signals. The time-frequency distribution of signals with the variation of orders of fractional Fourier transform was obtained, and the characteristics of the time-frequency distribution of different reservoirs under different orders were summarized. Because of the rotational characteristics of the fractional Fourier transform, the rotation speed of the cross terms was faster than those of primary waves, shear waves, Stoneley waves, and pseudo Rayleigh waves. By choosing different orders for different reservoirs according to the actual circumstances, the cross terms were separated from the four kinds of waves. In this manner, we could extract reservoir information by studying the characteristics of partial waves. Actual logging data showed that the method outlined in this paper greatly weakened cross-term interference and enhanced the ability to identify partial wave signals. 展开更多
关键词 Fractional Fourier transform smooth pseudo Wigner-Ville distribution arrayacoustic logging signal processing RESERVOIRS
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Design of programmable high-accuracy telemetric fast collection system
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作者 张海江 李晨彦 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期1-6,共6页
A programmable high-accuracy system was proposed to collect and process telemetric fast varying signals,which consists of pre-circuit,analog-to-digital(A/D)conversion unit and signal collection and processing part.P... A programmable high-accuracy system was proposed to collect and process telemetric fast varying signals,which consists of pre-circuit,analog-to-digital(A/D)conversion unit and signal collection and processing part.Performance analysis demonstrates that this novel telemetry-acquisition method is a potential solution to rapidly process fast varying signals and efficiently utilize telemetry channel. 展开更多
关键词 TELEMETRY signal collection fast varying signal
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Research on velocity and acceleration geophones and their acquired information 被引量:5
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作者 刘振东 吕庆田 +1 位作者 董世学 陈明春 《Applied Geophysics》 SCIE CSCD 2012年第2期149-158,234,共11页
Based on the research of two geophone types (10 Hz moving-coil velocity and piezoelectric acceleration) and their velocity and acceleration parameters, frequency response functions have been determined, as well as t... Based on the research of two geophone types (10 Hz moving-coil velocity and piezoelectric acceleration) and their velocity and acceleration parameters, frequency response functions have been determined, as well as the differences between them. Also, shock- vibration tests have been accomplished, not only to explain the two shock response signal differences, but also to analyze the response signal characteristics and its ability to carry information. In addition, seismic data acquisition experiments have been carried out under comparable conditions in the field. A contrast analysis of shot gathers and stack profiles acquired with the two geophone types is given in this paper. The results show that the acceleration signal from the acceleration geophone has a better advantage in terms of high signal-to-noise ratio, high accuracy, high resolution, and quantity of information to better meet current and future requirements for seismic exploration. 展开更多
关键词 seismic exploration GEOPHONE acceleration signal INTEGRITY ACCURACY
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Research on High-Accuracy Programmable Timer Used in Acquiring UWB Signals 被引量:1
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作者 苏红旗 杨峰 +1 位作者 马凯 康文献 《Applied Geophysics》 SCIE CSCD 2005年第2期127-130,F0003,共5页
UWB signal digitization depends, to a large extent, on the accuracy of sampling time. A highaccuracy programmable timer is therefore the key to implementing UWB signal data acquisition. A high-accuracy programmable ti... UWB signal digitization depends, to a large extent, on the accuracy of sampling time. A highaccuracy programmable timer is therefore the key to implementing UWB signal data acquisition. A high-accuracy programmable timer based on the principle of ramp generators is described in this paper. The counting range of the timer is up to 16 bits, the timing precision is 8 ps, and the equivalent sampling rate is up to 50G Hz. No other identical product has been reported so far. This timer was successfully used in the data acquisition system for geological radar signals developed by us. 展开更多
关键词 high-accuracy timing UWB signal data acquisition and ramp generator
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多元统计过程监控在FCCU中的应用 被引量:5
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作者 吴志伟 杨发新 赵仕健 《化工自动化及仪表》 EI CAS 北大核心 2004年第5期9-12,共4页
 介绍多元统计过程监控(MSPM)的技术特点,结合流化催化裂化装置(FCCU)的工艺,对MSPM在FC CU中关于多元统计过程监控位号集设计及软硬件实施等问题进行了讨论。
关键词 多元统计过程监控 FCCU 监控位
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国家建筑标准设计2005年新图简介
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《工程建设标准化》 2005年第6期33-33,5,3,共3页
《民用建筑工程设计互提资料深度及图样—建筑专业》图集号05SJ806本图集选择一栋民用建筑工程为实例,采用文字、图表及图示的表达方式,形象地表达了互提资料的内容和深度要求,直观地指导设计人员正确完成方案设计、初步设计、施工图设... 《民用建筑工程设计互提资料深度及图样—建筑专业》图集号05SJ806本图集选择一栋民用建筑工程为实例,采用文字、图表及图示的表达方式,形象地表达了互提资料的内容和深度要求,直观地指导设计人员正确完成方案设计、初步设计、施工图设计三个阶段互提资料的工作。 展开更多
关键词 建筑 集号 图样 民用建筑工程 梯形钢屋架 标准设计
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Integrated circuit for single channel neural signal regeneration 被引量:1
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作者 李文渊 王志功 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期155-158,共4页
Based on the 4-channel neural signal regeneration system which is realized by using discrete devices and successfully used for in-vivo experiments on rats and rabbits, a single channel neural signal regeneration integ... Based on the 4-channel neural signal regeneration system which is realized by using discrete devices and successfully used for in-vivo experiments on rats and rabbits, a single channel neural signal regeneration integrated circuit (IC)is designed and realized in CSMC ' s 0. 6 μm CMOS ( complementary metal-oxide-semiconductor transistor ) technology. The IC consists of a neural signal detection circuit with an adjustable gain, a buffer, and a function electrical stimulation (FES) circuit. The neural signal regenerating IC occupies a die area of 1.42 mm × 1.34 mm. Under a dual supply voltage of ±2. 5 V, the DC power consumption is less than 10 mW. The on-wafer measurement results are as follows: the output resistor is 118 ml), the 3 dB bandwidth is greater than 30 kHz, and the gain can be variable from 50 to 90 dB. The circuit is used for in-vivo experiments on the rat' s sciatic nerve as well as on the spinal cord with the cuff type electrode array and the twin-needle electrode. The neural signal is successfully regenerated both on a rat' s sciatic nerve bundle and on the spinal cord. 展开更多
关键词 neural signal regeneration function electrical stimulation integrated circuit ELECTRODE CMOS technology
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Method of combining space-time block coding with adaptive beamforming
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作者 沈克勤 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期254-259,共6页
A method of space-time block coding (STBC) system based on adaptive beamforming of cyclostationarity signal algorithm is proposed.The method uses cyclostationarity of signals to achieve adaptive beamforming,then con... A method of space-time block coding (STBC) system based on adaptive beamforming of cyclostationarity signal algorithm is proposed.The method uses cyclostationarity of signals to achieve adaptive beamforming,then constructs a pair of low correlated transmit beams based on beamform estimation of multiple component signals of uplink.Using these two selected transmit beams,signals encoded by STBC are transmitted to achieve diversity gain and beamforming gain at the same time,and increase the signal to noise ratio (SNR) of downlink.With simple computation and fast convergence performance,the proposed scheme is applicable for time division multiple access (TDMA) wireless communication operated in a complex interference environment.Simulation results show that the proposed scheme has better performance than conventional STBC,and can obtain a gain of about 5 dB when the bit error ratio (BER) is 10-4. 展开更多
关键词 space-time coding GAIN adaptive beamforming cyclostationary signal transmit diversity
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IDENTITY-BASED MULTISIGNATURE AND AGGREGATE SIGNATURE SCHEMES FROM M-TORSION GROUPS 被引量:11
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作者 Cheng Xiangguo Liu Jingmei +1 位作者 Guo Lifeng Wang Xinmei 《Journal of Electronics(China)》 2006年第4期569-573,共5页
An identity-based multisignature scheme and an identity-based aggregate signature scheme are proposed in this paper. They are both from m-torsion groups on super-singular elliptic curves or hyper-elliptic curves and b... An identity-based multisignature scheme and an identity-based aggregate signature scheme are proposed in this paper. They are both from m-torsion groups on super-singular elliptic curves or hyper-elliptic curves and based on the recently proposed identity-based signature scheme of Cha and Cheon. Due to the sound properties of m-torsion groups and the base scheme, it turns out that our schemes are very simple and efficient. Both schemes are proven to be secure against adaptive chosen message attack in the random oracle model under the normal security notions with the assumption that the Computational Diffie-Hellman problem is hard in the m-torsion groups. 展开更多
关键词 Identity-based multisignature Identity-based aggregate signature Weil pairing Gap Diffie-Hellman group m-torsion group
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miRNA在子痫前期发病中的作用机制研究进展 被引量:17
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作者 姚申珅 杜鹃 《山东医药》 CAS 2018年第3期103-105,共3页
子痫前期是妊娠期特有疾病,目前其发病机制尚不清楚。微小RNA(miRNA)是一类具有组织特异性、发育阶段特异性和疾病特异性表达的非编码小RNA,参与基因转录后水平的调控。子痫前期患者胎盘及血清中可检测到一些差异性表达的miRNA,以19号... 子痫前期是妊娠期特有疾病,目前其发病机制尚不清楚。微小RNA(miRNA)是一类具有组织特异性、发育阶段特异性和疾病特异性表达的非编码小RNA,参与基因转录后水平的调控。子痫前期患者胎盘及血清中可检测到一些差异性表达的miRNA,以19号染色体miRNA集簇为代表。这些miRNA可以通过多种靶基因参与妊娠滋养细胞的增殖和侵袭障碍,也可以通过调节血管生成因子及其受体来干扰血管生成过程,从而在子痫前期的发病机制中发挥有重要作用。 展开更多
关键词 子痫前期 微小RNA 19染色体微小RNA 滋养细胞 血管生成
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CDMA系统软切换过程浅析 被引量:1
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作者 于爱民 《电信技术》 2002年第9期34-36,共3页
介绍了CDMA系统软切换的概念、过程和特点,重点分析了软切换参数的定义与设置原则。
关键词 CDMA 软切换 导引信 切换参数 搜索窗口
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Symmetry Reductions and Group-Invariant Solutions of (2+1)-Dimensional Caudrey-Dodd-Gibbon-Kotera-Sawada Equation 被引量:2
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作者 吕娜 梅建琴 张鸿庆 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期591-595,共5页
With the aid of symbolic computation, we present the symmetry transformations of the (2+1)-dimensionalCaudrey-Dodd Gibbon-Kotera-Sawada equation with Lou's direct method that is based on Lax pairs. Moreover, witht... With the aid of symbolic computation, we present the symmetry transformations of the (2+1)-dimensionalCaudrey-Dodd Gibbon-Kotera-Sawada equation with Lou's direct method that is based on Lax pairs. Moreover, withthe symmetry transformations we obtain the Lie point symmetries of the CDGKS equation, and reduce the equation withthe obtained symmetries. As a result, three independent reductions are presented and some group-invariant solutions ofthe equation are given. 展开更多
关键词 symmetry reduction Caudrey-Dodd-Gibbon-Kotera-Sawada equation Lou's direct method group-invariant solution
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试论肖邦前奏曲的音乐特点与演奏要点 被引量:5
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作者 赵小红 《交响(西安音乐学院学报)》 1999年第4期39-43,共5页
文章旨在对肖邦的代表性作品——前奏曲集(作品28)从钢琴演奏和教学的角度进行综合研究。文中考察了肖邦这部杰作的创作过程及其在艺术上的三个突出特点,随后对所有二十四首前奏曲分别进行解剖和分析,论述了其中的音乐特征和演奏要点。
关键词 肖邦 前奏曲作品28 钢琴演奏与教学 音乐分析 音乐历史学
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Discuss on High Speed Data Acquisition and Signal Processing 被引量:1
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作者 Lixun LIU Yujuan SI 《International Journal of Technology Management》 2015年第4期50-53,共4页
In order to realize the high speed data acquisition and fast Fourier analysis, the paper put forward a kind of high speed data acquisition and analysis system based on FPGA, the system uses Cyclone series FPGA with hi... In order to realize the high speed data acquisition and fast Fourier analysis, the paper put forward a kind of high speed data acquisition and analysis system based on FPGA, the system uses Cyclone series FPGA with high-speed A/D converter, and use the fast Fourier custom analysis nucleation of Altera company, using the standard TCP/IP protocol communication with PC, match up the master machine based on Matlab GUI analysis software. We experiment high speed data acquisition and fast Fourier analysis for a plurality of groups of high frequency analog signals, at the same time the results display on the computer. The experimental results validate the fast Fourier analysis theory, and has realized the low cost, high performance data acquisition and analysis of the complete system design. 展开更多
关键词 FPGA high speed data acquisition fast Fourier analysis FIFO memory
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The research on signal-obtaining pattern for a new type of gyroscope 被引量:8
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作者 Jian-feng Liu Gan-nan Yuan Lei Zhao and Shi-jun Zhao 《Journal of Marine Science and Application》 2003年第2期46-52,共7页
In this paper, a photoelectric signal obtained scheme via equator triangle pattern engraved on rotor is discussed and the mathematic model is deduced in the case which is deflexion between rotor axis and the coordinat... In this paper, a photoelectric signal obtained scheme via equator triangle pattern engraved on rotor is discussed and the mathematic model is deduced in the case which is deflexion between rotor axis and the coordinate frame of case. The deflexion error and coupling error under the situation are analyzed. Finally, three methods of engraving based on the spherical triangle pattern are presented. The error models of various methods are built up and the simulation curves are provided respectively. We have done the primary experiments on the surface of rotor using this method. It can be seen from the enlarged figures that the rim of the pattern is smooth and the demand of sensor resolution is satisfied by and large. The results of study supply reference for signal obtaining. 展开更多
关键词 The new type of gyro optical signal obtaining system: triangle pattern graving technology
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Study of CMOS integrated signal processing circuit in capacitive sensors 被引量:1
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作者 曹一江 于翔 王磊 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第2期224-228,共5页
A CMOS integrated signal processing circuit based on capacitance resonance principle whose structure is simple in capacitive sensors is designed. The waveform of output voltage is improved by choosing bootstrap refere... A CMOS integrated signal processing circuit based on capacitance resonance principle whose structure is simple in capacitive sensors is designed. The waveform of output voltage is improved by choosing bootstrap reference current mirror with initiate circuit, CMOS analogy switch and positive feedback of double-stage inverter in the circuit. Output voltage of this circuit is a symmetric square wave signal. The variation of sensitive capacitance, which is part of the capacitive sensors, can be denoted by the change of output vohage's frequency. The whole circuit is designed with 1.5 μm P-weU CMOS process and simulated by PSpice software. Output frequency varies from 261.05 kHz to 47. 93 kHz if capacitance varies in the range of 1PF - 15PF. And the variation of frequency can be easily detected using counter or SCU. 展开更多
关键词 CMOS integrated Signal processing PSPICE Schmitt trigger
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