共查询到17条相似文献，搜索用时 437 毫秒
1.
ＴｈｅＢｅｉｊｉｎｇｎｅｔｗｏｒｋｏｆｄｉｇｉｔａｌｇｅｏｍａｇｎｅｔｉｃｐｕｌｓａｔｉｏｎｏｂｓｅｒｖａｔｏｒｉｅｓＪｕｎ－ＣｈｅｎｇＺＨＯＵ（周军成）；Ｋｅ－ＬｉＨＡＮ（韩克礼）；ＹｕｅＬＵ（鲁跃）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ，Ｓ... 相似文献
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Introduction The observation records of strong ground motion previously, on the one hand, supplied basicdata both to research on earthquake engineering and to constitute the criterion of aseismatic de-signing of all project structures; on the other hand, it provided important information for the re-search on the process of epicenter burst in seismology. With the development of research on strongground motion observation, especially the development of the new generation accelerograph,which… 相似文献
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Introduction Digital seismic observation systems originated from 1970′s. It has developed greatly in the past 30 years up to now. Its performances were improved, dynamic range and resolution increased a lot, the power consumption decreased a lot, and so on (YOU et al, 2003a, b). In a word, the dream of broad frequency-band, big dynamic range, digitalization of seismic observation has come true already. But, the previous digital seismic observation systems only support communica-tion based o… 相似文献
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1With the development of science and technology, the digital seismograph system has been adopted in large quantities for earthquake observation in China in recent years, which will replace gradually the original analog seismograph system. This is a big leap in the earthquake observation. The digital seismograph system make it pos-sible for us to perform fast great earthquake reports, obtain more information from earthquake records, which comes from the Earth interior media and the source proce… 相似文献
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（陈锦标，沈萍，郑治真）Ａｐｐｌｉｃａｔｉｏｎｏｆｄｉｇｉｔａｌｉｍａｇｅｐｒｏｃｅｓｓｉｎｇｔｏｔｈｅｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｓｐａｔｉａｌｄｉｓｔｒｉｂｕｔｉｏｎｏｆｅａｒｔｈｑｕａｋｅｓ￥Ｊｉｎ－ＢｉａｏＣＨＥＮ；ＰｉｎｇＳＨＥＮａｎｄＺ... 相似文献
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Coseismic effects of water temperature based on digital observation from Tayuan well, Beijing 总被引：1，自引：0，他引：1
On the basis of digital records from Tayuan well,we study coseismic effects of water temperature caused by re-mote earthquakes.The records show that the water temperature changes are consistently following the process ofdrop-rise-recovery regardless of focal mechanism or epicentral directions.The step amplitude of water temperatureincreases with the increase of earthquake magnitude,and decreases with the decrease of epicentral distances.Theyhave rather well correlation.Water temperature rising after earthquake is influenced by water level variations.Fi-nally,the mechanisms of coseismic effects of water temperature have been discussed.Preliminary study shows thataccelerated convection and mixing of different temperature water in virtue of seismic wave are the main causes ofwater temperature drops.Seismic wave accelerates water convection,which causes warm water to move up fromdeeper part of the well and cold water to go down from the upper part.Temperature probe will detect water tem-perature drops at early stage.After the occurrence of earthquake,as the fluctuation of water level gradually quietsdown,water temperature near the probe begins to rise. 相似文献
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Wail A. Mousa 《Geophysical Prospecting》2013,61(3):504-515
The purpose of this paper is to study the possibility of performing practically stable and efficient frequency‐space (f?x) wavefield extrapolation for the application of seismic imaging and datuming via infinite impulse response (IIR) filters. The model reduction control theory was adopted to design such IIR f?x extrapolation filters. The model reduction theory reduces the order of a given order system which, in this case, involves reducing a finite impulse response (FIR) f?x extrapolation filter system into an IIR f?x extrapolation filter system. This theory relies on decomposing the states of the given filter system into strong and weakly coupled sub‐systems, and then eliminating the weakly coupled states via singular value decomposition of the Hankel and the impulse response Gramian matrices. Simulation results indicate that IIR f?x filters can be obtained, which are stable from an IIR filter design point of view. Simulations also indicate that stable seismic impulse responses and synthetics can be obtained with a reduced system model order and, hence, less computational efforts with respect to the number of complex multiplications and additions per output sample. It is hoped that this study will open new possibilities for researchers to reconsider designing IIR f?x explicit depth extrapolation filters due to their expected computational savings and wavenumber response accuracy, when compared to the FIR f?x explicit depth extrapolation filters. 相似文献
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Introduction The so-called combined effect refers to the product (V( f )?P( f )) of the amplification factorand the high-frequency attenuation factor of sites (see Equation (1)). Whether the soft rock site orthe soil site, they have an amplification action on the ground motion of a certain frequency, andsimultaneously have an attenuation action on the motion of high frequency because they are softerthan the hard rock under them. The combined effect of soft rock is the very contents that … 相似文献
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ＳｏｕｒｃｅｐａｒａｍｅｔｅｒｓｏｆｔｈｅＧｏｎｇｈｅ，ＱｉｎｇｈａｉＰｒｏｖｉｎｃｅ，Ｃｈｉｎａ，ｅａｒｔｈｑｕａｋｅｆｒｏｍｉｎｖｅｒｓｉｏｎｏｆｄｉｇｉｔａｌｂｒｏａｄｂａｎｄｗａｖｅｆｏｒｍｄａｔａＬＩ－ＳＨＥＮＧＸＵ（许立生）ａｎｄＹＵＮ... 相似文献
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V. I. Mel’nikova N. A. Gileva N. A. Radziminovich O. K. Masal’skii V. V. Chechel’nitskii 《Seismic Instruments》2010,46(2):193-206
Some characteristics of the seismic regime of the Baikal rift zone for the analogue (1960–2000) and digital (2001–2006) registration
modes are considered. It was ascertained that the general number of seismic events recorded by digital equipment increased
by two times in comparison with the analogue observation period and the catalog completeness level was lowered to K
P = 7.0 as well. The focal mechanisms of 110 earth-quakes with K
P ≥ 8.0 were examined. The overwhelming majority of them during 2001–2006 were due to normal faulting and normal faulting with
strike-slip components. Special attention was given to study of the strong events (K
P ≥ 13.5 and MPSP ≥ 4.7), whose focal solutions reveal the regional stress field. 相似文献
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Wei Zuo Chunlai Li Lingjie Yu Zhoubin Zhang Rongwu Wang Xingguo Zeng Yuxuan Liu Yaying Xiong 《Acta Geochimica》2019,(4):541-554
This paper introduces a new method of small lunar craters’ automatic identification, using digital orthophoto map(DOM) data. The core of the approach is the fact that the lunar exploration DOM data reveal contrasting highlight and shadow characteristics of small craters under sunlight irradiation. This research effort combines image processing and mathematical modeling. Overall it proposes a new planetary data processing approach, to segment and extract the highlight and shadow regions of small craters,using the image gray frequency(IGF) statistical method.IGF can also be applied to identify the coupling relationships between small craters’ shape and their relative features. This paper presents the highlight and shadow pair matching(HSPM) model which manages to perform highprecision automatic recognition of small lunar craters.Testing was performed using the DOM data of Chang’E-2(CE-2). The results have shown that the proposed method has a high level of successful detection rate. The proposed methodology that uses DOM data can complement the drawbacks of the digital elevation model(DEM) that has a relatively high false detection rate. A hybrid fusion model(FUM) that combines both DOM and DEM data, was carried out to simultaneously identify small, medium, and large-sized craters. It has been proven that the FUM generally shows stronger recognition ability compared to previous approaches and it can be adapted for high precision identification of craters on the whole lunar surface.The results meet the requirements for a reliable and accurate exploration of the Moon and the planets. 相似文献
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Information is the foundation of evidence-based policies for effective marine environmental protection and conservation. In Canada, the cutback of marine science libraries introduces key questions about the role of such institutions and the management of ocean information in the digital age. How vital are such libraries in the mission of studying and protecting the oceans? What is the fate and value of the massive grey literature holdings, including archival materials, much of which is not in digital form but which often contains vital data? How important is this literature generally in the marine environmental sciences? Are we likely to forget the history of the marine pollution field if our digital focus eclipses the need for and access to comprehensive collections and skilled information specialists? This paper explores these and other questions against the backdrop of unprecedented changes in the federal libraries, marine environmental science and legislation in Canada. 相似文献
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Humans constitute one of the main geomorphological agents in modern times. As an example, post-mining regions represent a typical landscape of the Anthropocene. Strong relief modifications are particularly obvious with open pit mining. However, many existing mining areas are lacking detailed pre-mining information for the quantification of anthropogenic relief changes, which is a considerable challenge in regions with historic mining activities. Here, the Ville (Rhenish lignite district, Germany) is used to quantify surface mining induced relief changes in one of the oldest and currently largest lignite districts in Europe. Historical maps from first geodetic mapping in 1893 enabled construction of a historic digital elevation model to quantify the relief changes in comparison to elevation data from 2000 and 2015. The vertical accuracy of the historic data is remarkably high, with relief differences < 2 m in areas not affected by mining. In total, 49.2% of the investigated area (184 km2) shows a relief deficit and 14.5% has positive relief differences. Absolute changes account for more than 80 m heightening (dumpsites of overburden) and lowering of the natural relief (pits). Besides these altitudinal changes, overall steeper slopes are significant for the new topography, but levelling exists likewise. The spatial variabilities are discussed in the context of the regional geology and the mining techniques. Undoubtedly, such large-scale anthropogenic relief changes persist for a very long time and will last as a human legacy far into the future. Only the detailed reconstruction of the pre-mining relief offers the ability to clarify the dimension of humans as geomorphological agents and to understand landscape perception. Due to the fact that the impact of open pit mining has such a large vertical and horizontal extension, their consideration as part of anthropogeomorphology can significantly contribute to support future Critical Zone research in the Anthropocene. 相似文献
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Source time functions of the Gonghe，China earthquake retrieved from long－period digital waveform data using empirical Green＇s function technique 总被引：2，自引：0，他引：2
ＳｏｕｒｃｅｔｉｍｅｆｕｎｃｔｉｏｎｓｏｆｔｈｅＧｏｎｇｈｅ，Ｃｈｉｎａｅａｒｔｈｑｕａｋｅｒｅｔｒｉｅｖｅｄｆｒｏｍｌｏｎｇ－ｐｅｒｉｏｄｄｉｇｉｔａｌｗａｖｅｆｏｒｍｄａｔａｕｓｉｎｇｅｍｐｉｒｉｃａｌＧｒｅｅｎ＇ｓｆｕｎｃｔｉｏｎｔｅｃｈｎｉｑ... 相似文献
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《水文科学杂志》2013,58(6):1176-1193
Abstract Flat areas are a critical issue for the characterization of drainage patterns using digital elevation models (DEM). In this work, flat area removal and flow direction algorithms are implemented, and also a physically-based DEM correction model is introduced, for investigating their influence on the topological properties of the channel network, the Hortonian parameters and the hillslope width function. Differences of results, as compared to the standard procedures implemented in widely-used GIS-based hydrological packages, show the importance for hydrogeomorphic modellers to consider the use of more detailed approaches. 相似文献