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柴达木盆地三湖地区地震采集方法探讨
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作者 罗岐峰 于宝华 +3 位作者 吴明生 翟俊伟 潘建勇 马立新 《石油地球物理勘探》 EI CSCD 北大核心 2011年第6期837-843,1012+829,共7页
柴达木盆地三湖地区富含天然气藏,以往在地震数据采集中多采用突出炮点、检波点组合作用的方法压制和削弱干扰波,难以达到预期效果。如今采用高精度地震勘探,突出观测系统的优化设计,并利用地震数据处理中的水平叠加进行噪声压制,充分... 柴达木盆地三湖地区富含天然气藏,以往在地震数据采集中多采用突出炮点、检波点组合作用的方法压制和削弱干扰波,难以达到预期效果。如今采用高精度地震勘探,突出观测系统的优化设计,并利用地震数据处理中的水平叠加进行噪声压制,充分提高地震数据的信噪比和分辨率。本文针对目标工区地质任务及地震勘探难点,对比研究噪声干扰特性,剖析以往地震勘探中存在的问题,并论述了叠加响应对高精度地震勘探所起的积极作用,为该区天然气勘探提供高质量、高精度地震数据。 展开更多
关键词 地震数据采集 观测系统 组合 水平叠加 压噪特性 比与分辨率 高精度勘探
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柴达木盆地三湖地区——观测系统对高精度地震采集资料的影响
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作者 罗岐峰 于宝华 +2 位作者 王海立 翟俊伟 赵荣艳 《青海石油》 2010年第4期13-19,共7页
通过对柴达木盆地三湖地区的天然气地震勘探资料分析,以往的地震勘探以及高分辨率勘探,以突出炮、检组合的作用进一步压制和削弱干扰波,提高地震资料的信噪比和分辨率,虽然勘探取得了长足的进步,但仍没有达到预期的效果。而高精度地震勘... 通过对柴达木盆地三湖地区的天然气地震勘探资料分析,以往的地震勘探以及高分辨率勘探,以突出炮、检组合的作用进一步压制和削弱干扰波,提高地震资料的信噪比和分辨率,虽然勘探取得了长足的进步,但仍没有达到预期的效果。而高精度地震勘探,以突出观测系统的优化设计为目的,利用资料处理中的水平叠加组合进行噪音压制,使地震剖面的信噪比和分辨率有了质的提高,满足了天然气勘探的地质认识。笔者针对探区的地质任务及地震勘探难点,从干扰波噪音的特性分析出发,从理论上分析以往勘探失败的原因,进一步论述观测系统设计对高精度勘探所起的作用。 展开更多
关键词 高精度勘探 炮点、检波点组合 叠加组合 覆盖次数 压噪特性 分辨率
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Design of Low-Voltage Low Noise Amplifiers with High Linearity 被引量:2
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作者 曹克 杨华中 汪蕙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第11期1364-1369,共6页
A CMOS radio frequency low noise amplifier with high linearity and low operation voltage of less than 1.0V is presented.In this circuit,an auxiliary MOSFET in the triode region is used to boost the linearity.Simulatio... A CMOS radio frequency low noise amplifier with high linearity and low operation voltage of less than 1.0V is presented.In this circuit,an auxiliary MOSFET in the triode region is used to boost the linearity.Simulation shows that this method can boost the input-referred 3rd-order intercept point with much less power dissipation than that of traditional power/linearity tradeoff solution which pays at least 1dB power for 1dB linearity improvement.It is also shown that the size of the common-gate PMOS transistor needs to be optimized to reduce its loaded input impedance so as not to degrade the linearity due to high voltage gain at its source terminal.The simulation is carried out with TSMC 0.18μm RF CMOS technology and SpectreRF. 展开更多
关键词 LOW-VOLTAGE radio frequency CMOS low noise amplifier LINEARITY
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Characteristic and Mechanism of Pressure Fluctuation Caused by Self-Induced Oscillation of Supersonic Impinging Jet
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作者 Tsuyoshi Yasunobu Yumiko Otobe Hideo Kashimura 《Journal of Thermal Science》 SCIE EI CAS CSCD 2013年第2期123-127,共5页
When the underexpanded supersonic jet impinges on the obstacle, it is well known that the self-induced flow os- cillation occurs. This oscillation depends on the pressure ratio in the flowfield, the position of an obs... When the underexpanded supersonic jet impinges on the obstacle, it is well known that the self-induced flow os- cillation occurs. This oscillation depends on the pressure ratio in the flowfield, the position of an obstacle and is related with the noise problems of aeronautical and other industrial engineering. The characteristic and the mechanism of self-induced flow oscillation, have to be clarified to control various noise problems. But, it seems that the characteristics of the oscillated flowfield and the mechanism of an oscillation have to be more cleared to control the oscillation. This paper aims to clarify the effect of the pressure ratio and the obstacle position and the mechanism of self-induced flow oscillation by numerical analysis and experiment, when the underexpanded su- personic jet impinges on the cylindrical body. From the result of this study, it is clear that occurrence of the self-induced flow osciUation depends on the pressure balance in the flowfield. 展开更多
关键词 Supersonic Jet Mach Disk Barrel Shock Flow Oscillation Flow Visualization Numerical Analysis
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