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doppler effect of the rupture process of the great M_W7.9 Wenchuan earthquake

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Earthquake Science 2010年第6期23卷 535-539页

作者： Ge Jin Youcai Tang Shiyong Zhou Yongshun John Chen Institute of Theoretical and Applied Geophysics (ITA G) School of Earth and Space Sciences Peking University Beijing 100871 China Lamont-Doherty Earth Observatory Columbia University in the New York City Palisades NY 10964 USA

In this study we performed a classical spectrum analysis of seismic waveforms recorded at far field stations of the great MW7.9 Wenchuan earthquake to observe the shifts of the corner frequency with azimuth due to the doppler *** results show that this damaging great earthquake had a dominating rupture propagation direction of 64.0°.The equivalent radius of the fault rupture surface was estimated to be 33 km,yielding the rupture area of about 3 500 *** the length of the rupture fault surface is about 230 km if the depth（or width） extent is 15 *** computer program developed in this study can quickly provide the information about the source of a future large（damaging） earthquake,which could be very useful for predicting aftershocks and planning the rescue operations.

关键词： doppler effect rupture process Wenchuan earthquake corner frequency unidirectional

Residual doppler effect on Electromagnetically Induced Transparency in a Zeeman Sublevel System

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Chinese Physics Letters 2010年第5期27卷 138-141页

作者：胡振燕李路明陈佩荣孙欣 School of Electronics and Computer Science Peking University Beijing 100871 Department of Communication Jiangxi Electric Power Information and Communication Company Nanchang 330029

We investigate the residual doppler effect on the linewidth of electromagnetieally induced transparency （EIT） in a Zeeman sublevel system where a careful experimental design ensures the smallest measurement error. The overall measurement error of the EIT linewidth is estimated to be less than 5%. We present the linear dependence of EIT resonance broadening at small angular deviation in detail. The theoretical analysis exploits the dependence of this feature and shows the qualitative agreement between numerical results and experimental results.

关键词： doppler effect ELECTROMAGNETIC induction TRANSPARENCY (Optics) ZEEMAN effect EXPERIMENTAL design MEASUREMENT errors QUALITATIVE research NUMERICAL analysis

The doppler effect induced by earthquakes:A case study of the Wenchuan MS8.0 earthquake

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Geodesy and Geodynamics 2022年第5期13卷 435-444页

作者： Qicheng Li Jingwen Sun Guimei Xi Jing Liu Mining College Liaoning Technical UniversityLiaoning 123000China Chaoyang Teachers College Liaoning 122000China Chaoyang Open University Liaoning 122000China

Seismologists have found that the first arrival frequencies of P waves at different seismic stations have different widths,that is,different periods or frequencies,and they think that this phenomenon can be used to identify whether a doppler effect is induced by ***,the fault rupture process of a real earthquake is so complex that it is difficult to identify a frequency shift similar to the doppler effect.A method to identify whether a doppler effect is induced by an earthquake is proposed *** a seismic station is in the direction of fault rupture propagation,this station could observe a doppler effect induced by the *** doppler effect causes the frequency of the seismic wave to shift from low frequency to high frequency,and the high frequency amplitudes become mutually *** the combined influences of the absorption effect,geometric spreading effect and doppler effect,the high frequency amplitude of the seismic wave will gradually become higher than the low frequency amplitude with increasing epicentral *** we find that the high frequency amplitude is higher than the low frequency amplitude with increasing epicentral distance in the direction of fault rupture propagation,then there is a doppler *** fault that generated the Wenchuan earthquake is a reverse fault,and its horizontal rupture propagation velocity was *** link fault rupture propagation velocity with the doppler effect and identify the doppler effect more easily,we decompose three-component records into two directions:the direction of fault rupture propagation and the direction perpendicular to the fault rupture propagation along the fault *** initial components of the two directions are processed by wavelet *** seismic stations in the direction of fault rupture propagation of the Wenchuan earthquake were selected,and it was found that with increasing epicentral distance,the high frequency amplitudes of the wavelet spectra b

关键词： doppler effect First arrival frequency of P wave Fault rupture propagation velocity Wavelet transform The wenchuan earthquake

Design of new seismometer based on laser doppler effect

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Chinese Optics Letters 2004年第4期2卷 217-219页

作者：杜振辉黄福祥蒋诚志陶知非高华吕丽娜 State Key Lab of Precision Measuring Technology and Instruments Tianjin University Tianjin 300072 State Key Lab of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072 State Bureau of Oil and Physical Geography Exploration Zhuozhou 072751

In order to improve the resolution of seismic acquisition,a new seismic acquisition system based on tangential laser doppler effect with an optimized differential optical configuration is *** relative movement of the inertia object and the immobile frame is measured by laser doppler effect,which can avoid the electromagnetic and thermometric interference,and the adoption of frequency-modulated (FM) transmission can improve the ability of *** frequency bandwidth is properly determined by analyzing the frequency of the doppler *** velocity, displacement,acceleration, and frequency to be measured can be real-time acquired by frequency/velocity (F/V) converting the FM doppler signal. A 100-dB dynamic range and the linear frequency range of 1.0 to 1000 Hz are realized.

关键词： doppler effect Frequency modulation Laser doppler velocimeters

Radio interferometric localization of WSNs based on doppler effect

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Science China(Information Sciences) 2010年第1期53卷 158-167页

作者： ZHANG WeiLe, YIN QinYe, HAN Wei & WANG WenJie School of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an 710049, China 1. School of Electronic and Information Engineering Xi’an Jiaotong University Xi’an 710049 China

A novel distributed localization method based on the doppler effect for wireless sensor networks is proposed in this paper, which only relies on radio transceivers without the need of other auxiliary measurement equipments. Based on radio interference, each sensor node can obtain a multi-group of distance variations from itself to a mobile anchor through the measurement of the cumulative phase variations caused by doppler effect, by which its position can be determined. The proposed method has the following advantages: the sensor node conducts localization in a completely distributed manner without information exchange or centralized processing, and the measurement result equals the actual distance without modulus operation, which is in reality measuring the distance with a ruler of radio wavelength, and will significantly reduce the system complexity and achieve high location accuracy. Analysis and simulation results demonstrate the effectiveness of our proposed method.

关键词： radio interference doppler effect hyperbolic localization WSN

Experimental Studies of the doppler effect

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Journal of Systems Engineering and Electronics 1995年第4期6卷 115-128页

作者： L. A. Pobedonostsev (Radium Institute, Pr. Shvernika 28, 194021 St. Petersburg, Russia) Radium Institute Pr. Shvernika 28 194021 St. Petersburg Russia

Recent experimental results of the doppler effect formula verification are reported. The moving emitters are hydrogen atoms in the excited state. The results of the work corroborate the classical not the relativistic,... 详细信息

关键词： doppler effect Hydrogen atom Experimental results Relativity.

TRANSVERSE VELOCITY ESTIMATION BASED ON HIGH-ORDER doppler effect OF MOVING OBJECT

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Transactions of Nanjing University of Aeronautics and Astronautics 2009年第3期26卷 224-228页

作者：张兴敢柏业超南京大学电子科学与工程系

The one-order phase of the echo changes if there is relative radial moving between the object and the radar, i.e. , the doppler effect. The doppler effect is widely used in radar signal processing. The transverse motion of the object cannot change the one-order phase of the echo, but the high-order phase. The high-order doppler effect of the transverse moving target is presented and a new algorithm for obtaining the transverse velocity is given. The scalar velocity of a target moving steadily in any direction can be calculated with one-order and two-order items of the echo phase. The calculating method and simulating results are given. As the transverse speed is 900 km/h, the speed calculation error is less than 0. 06% if SNR of echo signal is higher than 0 dB.

关键词： doppler effect curve fitting transverse movement phase difference

Analysis of Focal Depth of Remote Displacement Measuring System Based on Grating doppler effect

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Chinese Journal of Lasers 1998年第6期 76-80页

作者： YANG Xin ZHANG Guoxiong JIANG Chengzhi GAO Xiang (College of Precision Instrument and Opto electronics Engineering, Tianjin University, Tianjin 300072, China)

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１ＩｎｔｒｏｄｕｃｔｉｏｎＬａｓｅｒＤｏｐｐｌｅｒｔｅｃｈｎｉｑｕｅｉｓａｃｏｍｐｒｅｈｅｎｓｉｖｅｔｅｃｈｎｉｑｕｅｒｅｌｅｖａｎｔｔｏｏｐｔｉｃｓ，ｌａｓｅｒ，ｏｐｔｏｅｌｅｃｔｒｏｎｉｃｄｅｔｅｃｔｉｎｇａｎｄｓｉｇｎａｌｐｒｏｃｅｓｉｎｇ．...

关键词： doppler effect remote measurement focal depth displacement measuring

Parameter Influence Analysis for Velocity-Measurement Navigation Target Source with Asymmetric Spatial Heterodyne Technology based on doppler effect

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Parameter Influence Analysis for Velocity-Measurement Naviga...