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The relation between the response spectrum and the phase diference spectrum 被引量:1
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作者 赵凤新 胡聿贤 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第3期13-18,共6页
The relation between the phase difference spectrum and the response spectrum is studied in this paper. It is found that the phase difference spectrum influences the response spectrum through affecting the response ... The relation between the phase difference spectrum and the response spectrum is studied in this paper. It is found that the phase difference spectrum influences the response spectrum through affecting the response motion′s envelope function shape of a single degree of freedom system. Decreasing the variance of phase difference spectrum causes the increasing of response spectrum when its mean value curve keeps the same, otherwise the situation is opposite. As the increase of the tangent of the mean value curve, the response spectrum decreases, otherwise it increases. The damping plays an important role while the phase difference spectrum influences the response spectrum. The effect of the phase difference spectrum on the absolute acceleration response spectrum becomes more and more obvious with the increase of the damping. On the other hand, the increase of damping weakens the effect of the phase difference spectrum on the amplification factor spectrum. 展开更多
关键词 ground motion response spectrum phase difference spectrum.
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APPLICATION OF WEIGHTED NONOSCILLATORY AND NON-FREE-PARAMETER DISSIPATION DIFFERENCE SCHEME IN CALCULATING THE FLOW OF VIBRATING FLAT CASCADE
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作者 XIAO Jun GU Chuangang SHU Xinwei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第6期69-73,共5页
A dual-time method is introduced to calculate the unsteady flow in a certain vibrating flat cascade. An implicit lower-upper symmetric-gauss-seidel scheme(LU-SGS) is applied for time stepping in pseudo time domains,... A dual-time method is introduced to calculate the unsteady flow in a certain vibrating flat cascade. An implicit lower-upper symmetric-gauss-seidel scheme(LU-SGS) is applied for time stepping in pseudo time domains, and the convection items are discretized with the spatial three-order weighted non-oscillatory and non-free-parameter dissipation difference (WNND) scheme. The turbulence model adopts q-co low-Reynolds-number model. The frequency specmuns of lift coefficients and the unsteady pressure-difference coefficients at different spanwise heights as well as the entropy contours at blade tips on different vibrating instants, are obtained. By the analysis of frequency specmuns of lift coefficients at three spanwise heights, it is considered that there exist obvious non-linear perturbations in the flow induced by the vibrating, and the perturbation frequencies are higher than the basic frequency. The entropy contours at blade tips at different times display an intensively unsteady attribute of the flow under large amplitudes. 展开更多
关键词 Vibrating cascade Weighted non-oscillatory and non-free-parameter dissipation difference scheme Frequency spectrum of lift coefficient Unsteady pressure-difference coefficient
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The statistical laws of strong seismic motion phase characteristics
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作者 金星 廖振鹏 《Acta Seismologica Sinica(English Edition)》 CSCD 1994年第1期141-147,共7页
Under the assumption of an effective point source model,this paper introduces a conception of equivalent phase velocity to describle the average propagation processes and dispersion properties of seismic waves from se... Under the assumption of an effective point source model,this paper introduces a conception of equivalent phase velocity to describle the average propagation processes and dispersion properties of seismic waves from seismic source to the site,then illuminates the relation between the phase properties of seismic motion and equivalent phase velocity and obtains a simple formula of estimating the equivalent phase velocity through the use of the phase difference spectrum of seismic motion.After the parts of strong seismic records in the western American and the SMART-1 array are used to identify the method presented by this paper in reason,the statistical relations of equivalent phase velocity are given in the above two regions.The results of the paper have demonstrated that the phase spectrum of seismic motion has its inner law as same as the amplitude spectrum does. 展开更多
关键词 equivalent phase velocity relative phase velocity phase spectrum relative group velocity phase difference spectrum
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Sex Differences in Diagnosis and Clinical Phenotypes of Chinese Children with Autism Spectrum Disorder 被引量:3
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作者 Shihuan Wang Hongzhu Deng +6 位作者 Cong You Kaiyun Chen Jianying Li Chun Tang Chaoqun Ceng Yuanyuan Zou Xiaobing Zou 《Neuroscience Bulletin》 SCIE CAS CSCD 2017年第2期153-160,共8页
The aim of this study was to explore the differences between boys and girls in the diagnosis and clinical phenotypes of autism spectrum disorder(ASD) in China's mainland. Children diagnosed with ASD(n = 1064, 228 ... The aim of this study was to explore the differences between boys and girls in the diagnosis and clinical phenotypes of autism spectrum disorder(ASD) in China's mainland. Children diagnosed with ASD(n = 1064, 228 females) were retrospectively included in the analysis. All children were assessed using the Autism Diagnostic Interview-Revised(ADI-R) and Autism Diagnostic Observation Schedule(ADOS). The results showed that girls scored significantly higher in ADI-R socioemotional reciprocity than boys, and also scored lower in ADI-R and ADOS restricted and repetitive behaviors(RRBs). Meanwhile, the proportions of girls who satisfied the diagnostic cut-off scores in the ADI-R RRBs domain were lower than in boys(P / 0.05). Our results indicated that girls with ASD show greater socio-emotional reciprocity than boys. Girls also tended to show fewer RRBs than boys, and the type of RRBs in girls differ from those in boys. The ADI-R was found to be less sensitive in girls, particularly for assessment in the RRBs domain. 展开更多
关键词 Autism spectrum disorder Sex differences Diagnosis
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Effects of Signal Spectrum Bandwidth on Different PMD Compensation Feedback Methods
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作者 Na Young Kim Duckey Lee +1 位作者 Sangin Kim Namkyoo Park 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期581-582,共2页
We compared efficiencies of different PMD compensation feedback methods against transmission signal bandwidth, including NRZ, RZ, CRZ format under various duty cycles. We found that the critical factor determining the... We compared efficiencies of different PMD compensation feedback methods against transmission signal bandwidth, including NRZ, RZ, CRZ format under various duty cycles. We found that the critical factor determining the efficiency of PMD compensation is not the modulation format, but the spectral bandwidth of the transmission signal. 展开更多
关键词 PMD PMDC Effects of Signal spectrum Bandwidth on Different PMD Compensation Feedback Methods of DOP on
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