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油气藏烃类微渗漏理论及遥感油气资源探测的机理研究 被引量:21
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作者 朱振海 《遥感技术与应用》 CSCD 1994年第1期1-10,共10页
油气藏烃类微渗漏理论是油气资源遥感直接探测的理论依据,本文叙述了油气藏烃类微渗漏的一些新论点及研究的进展。遥感技术探测地下油气的有利聚集,主要是捕获油气藏烃类微渗漏的一系列地表“蚀变”标志。给出了一个概念模型,共综合... 油气藏烃类微渗漏理论是油气资源遥感直接探测的理论依据,本文叙述了油气藏烃类微渗漏的一些新论点及研究的进展。遥感技术探测地下油气的有利聚集,主要是捕获油气藏烃类微渗漏的一系列地表“蚀变”标志。给出了一个概念模型,共综合了七种有效的标志,并重点介绍了遥感探测地表土壤烃组分异常标志的机理。介绍了两个以地在土壤烃组分异常标志为主的多元遥感信息复合分析的应用实例,分析结果与实际符合较好。 展开更多
关键词 油气藏 烃类微渗漏 遥感 探测
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随机振动载荷下导弹吊挂疲劳寿命分析 被引量:19
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作者 张翼 杨晨 罗杨阳 《机械科学与技术》 CSCD 北大核心 2013年第11期1675-1679,共5页
基于结构振动疲劳寿命分析方法,采用有限元分析软件对某型导弹吊挂在挂飞过程中承受随机振动载荷产生的疲劳破坏问题进行了研究。利用有限元软件对全弹的前3阶弯曲模态进行了分析,并和地面试验数据进行对比发现误差在15%以内,表明所建... 基于结构振动疲劳寿命分析方法,采用有限元分析软件对某型导弹吊挂在挂飞过程中承受随机振动载荷产生的疲劳破坏问题进行了研究。利用有限元软件对全弹的前3阶弯曲模态进行了分析,并和地面试验数据进行对比发现误差在15%以内,表明所建立的模型符合工程要求;其次,基于振动疲劳寿命频域法中的Dirlik雨流分布模型,采用Dirlik经验公式对导弹吊挂在耐久振动和机动抖振下的疲劳损伤和疲劳寿命进行了研究和估算。结果表明:导弹吊挂在耐久振动和机动抖振下均满足飞行寿命需求,且在机动抖振下的寿命比在耐久抖振的寿命要短。 展开更多
关键词 吊挂 随机振动 有限元分析 疲劳寿命估算
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A new family of windows——convolution windows and their applications 被引量:7
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作者 ZHANG Jieqiu1,2, LIANG Changhong1 & CHEN Yanpu3 1. Department of Applied Math. & Phys., College of Science, Airforce Engineering University, Xi’an 710051, China 2. National Key Laboratory of Antennas and Microwave Technology, Xidian University, Xi’an 710071, China 3. Computer Center, Xi’an Communication College, Xi’an 710106, China 《Science China(Technological Sciences)》 SCIE EI CAS 2005年第4期468-480,共13页
A new family of windows is constructed by convolutions via a few rectangular windows with same time width and is thus referred to as convolution windows. The expressions of the second-order up to the eighth-order conv... A new family of windows is constructed by convolutions via a few rectangular windows with same time width and is thus referred to as convolution windows. The expressions of the second-order up to the eighth-order convolution windows in both the time and frequency domains are derived. Their applications in high accuracy harmonic analysis of periodic signals are investigated. Comparisons between the proposed windows and some known windows with the same width shows that, when the synchronous deviation of data sampling is slight, the proposed ones have the least effect of spectral leakage. Therefore, the new windows are well suited for high accuracy harmonic analysis and parameter estimation for periodic signals. The error analysis and computer simulations show that the estimation errors, corresponding to frequency, amplitude and phase of every harmonic component of a signal, are proportional to the pth power of the relative frequency deviation in case of the pth-order convolution window is applied to windowing signal of approximately p cycles. By introducing real time adjustment in sampling interval, the proposed algorithm can adaptively trace signal frequency and lead to less sampling synchronous deviation. The proposed approach has the advantages of easy implementation and high measure precision and can be used in harmonic analysis of quasi-periodic signals whose fundamental frequency drifts slowly with time. 展开更多
关键词 signal processing harmonic analysis window function convolution window synchronous error spoctral leakage
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