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91.
92.
93.
同时满足多个阻尼反应谱的人造地震动时程合成 总被引:1,自引:0,他引:1
应用M.Hirasawa和M.Watabe(1992)提出的方法,进行了相应的数学推导:即以满足某个阻尼比的反应谱的人造地震动作为初始时程,采用奇异值分解法,通过解线性方程组求出校正时程,并多次叠以逐步辐近 相似文献
94.
Identification method of weak seismic phases on the basis of wavelet packet transform 总被引:1,自引:0,他引:1
Xi-Qiang Liui Hui-Lan Zhou Zhi-Zhen Zheng Ping Shen Xuan-Hui Yang Yan-Lu Ma 《地震学报(英文版)》1998,11(4):431-439
This paper describes a sort of new method identifying seismic phase by the name of wavelet packet transform. Perfectness and
development of the wavelet packet transform is based upon the idea of its multiscale analysis. The method of wavelet packet
transform can depict the anomalous changes information of transient spectra of seismic wave onset, and come true the target
of identifying seismic phase especially weak seismic phase. Then this paper presents discriminating examples of simulating
digital signals and actual seismic phase. Compared with conventional seismic phase discrimination, studied results show that
the wavelet packet transform method is an available tool of weak signal analyses, and have unexampled merits and attractive
application foreground.
This research gets hold of Higher School Doctor Scientific Research Foundation (No. 157 WJ0704 9435611) and supported by the
National Natural Science Foundation (No. 49474211). 相似文献
95.
应用富时叶变换红外谱仪研究了三个启三绿柱石样(包括原样与热处理)。将3435cm^-1宽吸收带归属于与铁离子成键的水。谱图表明隧道水的大量脱去是在800℃以上的温度开始的,对于富碱样品,更可能是在1000℃以后开始。隧道中碱金属离子的阻塞作用是造成绿柱石隧道水难以失去的重要原因. 相似文献
96.
A numerical approach to the earthquake ground motion analysis is proposed for regions where no accelerograms are available. Using Haskell matrix techniques, the response spectra of a layered substratum for SV waves were calculated and then multiplied by the spectra corresponding to Brune's type pulses. The ground acceleration spectra were obtained for different angles of pulse incidence at the substratum base. The spectrum shape depends upon the substratum response and the pulse shape, while its level was related to the maximum ground acceleration corresponding to the expected maximum intensity. Transformation of the ground spectra into the time domain produced numerical accelerograms for horizontal and vertical components and for different angles of pulse incidence. Finally, a standard statistical procedure was applied to obtain the design response spectra used in engineering applications. 相似文献
97.
Victoria M. Kaspi 《Astrophysics and Space Science》2007,308(1-4):1-11
I review recent observational progress on Anomalous X-ray Pulsars, with an emphasis on timing, variability, and spectra. Highlighted
results include the recent timing and flux stabilization of the notoriously unstable AXP 1E 1048.1–5937, the remarkable glitches
seen in two AXPs, and the newly recognized variety of AXP variability types, including outbursts, bursts, flares, and pulse
profile changes. I also discuss recent discoveries regarding AXP spectra, including their surprising hard X-ray and far-infrared
emission, as well as the pulsed radio emission seen in one source. Much has been learned about these enigmatic objects over
the past few years, with the pace of discoveries remaining steady. However additional work on both observational and theoretical
fronts is needed before we have a comprehensive understanding of AXPs and their place in the zoo of manifestations of young
neutron stars.
相似文献
98.
为探究不同光谱下许氏平鲉的消化代谢水平及外周激素节律,在5种光谱(红光、绿光、黄光、蓝光、白光,光周期12L∶12D)下,通过对许氏平鲉的血清、肠道、肝脏进行24 h (8:00,12:00,16:00,20:00,24:00)取样,结果显示:不同的光谱下许氏平鲉的消化代谢酶活性除胰蛋白酶(TRY)外均具有节律性,红光、黄光下α-淀粉酶(α-AMS)、脂肪酶(LPS)活性的峰值相位与白光组相比左移;胰蛋白酶活性无时间差异性;在绿光、黄光及红光下乳酸脱氢酶(LDH)活性的峰值相位与白光组相比发生左移,在五种光谱环境中,红、黄光影响消化酶活性峰值提前出现;丙酮酸激酶(PK)活性在绿、蓝及红光下峰值相位左移;己糖激酶(HK)的活性在绿、蓝、黄光下,其峰值相位与白光组相比发生左移,在五种光谱环境中,绿、蓝光影响代谢酶活性类峰值提前出现。许氏平鲉血清中褪黑素含量呈现昼低夜高分泌水平;皮质醇的含量表现为在白天降低,午夜显著升高至最高值后又持续降低。峰值相位的改变预示着生理节律的变动,以上结果表明不同光谱可以影响鱼类的生理代谢节律,在今后养殖过程中需要充分考虑光谱对养殖生物的生物学作用,进而制定更为合理的光照条件。 相似文献
99.
Spectroscopic data taken with a moderate resolution spectrograph in the region of the Hα and Hβ lines are presented for the
Herbig B8e star MWC 419. The spectroscopic observations were accompanied by broad band BVR photometric measurements. The observations
reveal a variability in the line profiles that is typical of Herbig Ae/Be stars with signs of a strong stellar wind. The greatest
changes are observed in the region of the absorption components of the line profiles, which convert the profile from a type
P CygII to P CygIII, as well as in the intensities of the central emission components. A model technique is used for quantitative
interpretation of this variability and it shows that the P Cyg profile conversion of the absorption component can be explained
in terms of a stellar wind model in which its distribution over latitude varies on a time scale of a few days.
__________
Translated from Astrofizika, Vol. 50, No. 2, pp. 259–280 (May 2007). 相似文献
100.
以海拉尔地区为例,提出了基于核磁共振T2谱构建水谱库进行流体性质识别的一种新方法,实测核磁谱包含了孔隙结构、水和油气的信息,构建的水谱来自于水层的核磁实测谱,相当于消除了油气的影响,其基本原理是应用构建的水谱库与实测谱的差异识别流体性质。通过在海拉尔地区应用,得到了较好的应用效果。 相似文献