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991.
????????????????SAR??????????????????????????????????????????????????????????????????????????????????????????????????????????????仯?????????????????????????仯????????????????????????????????????????EM????????????????в????????????????????С????????б仯????????????????????????仯????????б?????????????????????????????????仯??????????????????????????????С?????и??????Ч???? 相似文献
992.
Slope seismic response monitoring on the aftershocks of the Wenchuan earthquake in the Mianzhu section 总被引:1,自引:0,他引:1
Previous investigations have shown that the seismic response of slopes during the Wenchuan earthquake was highly variable.The present study tries to give an answer to the question:Which are the main factors affecting the seismic response degree of slopes? With the support of the China Geological Survey Bureau,we set 3 monitoring sections in Jiulong slope,Mianzhu city,China with the aim to record the site response of the slope during the aftershocks of the Wenchuan earthquake.After the Wenchuan earthquake,which happened on 12 May 2008,30 aftershocks have been recorded in these monitoring points.We analyzed 11 records,with magnitudes ranging from ML = 4.6 to ML = 3.1.The amplification factors of the horizontal compound PGA and 3D compound PGA have been determined for the 3 points at different elevations on the slope.Results showed that the dynamic response of the slope on the earthquake was controlled by factors such as topography and the thickness of the Quaternary overburden. 相似文献
993.
Shuo Wang Yuanyong Deng Rajmal Jain Vasyl Yurchyshyn Haimin Wang Yuanyuan Liu Zhiliang Yang 《Journal of Astrophysics and Astronomy》2008,29(1-2):57-61
In this paper, we study the evolution of vector magnetic field of AR 10656 by using the observations of Huairou Solar Observing Station (HSOS, China) and Big Bear Solar Observatory (BBSO, USA). The magnetic flux emergence and cancellation, and thus, magnetic nonpotential changes, are associated with the major flares in this active region. Compared with some other super-active regions, the evolution of magnetic morphologies and non-potentialities are relatively gradual, and thus the energy transportation and release are relatively slow. This gradual process may result in the recurrent flares of AR 10656. 相似文献
994.
Two-dimensional bulge/disk light decomposition with GIM2D in both the r-and g-bands has been applied to a sample of 129 early-type galaxies brighter than 13.5 magnitude in the r-band,selected from the Sloan Digital Sky Survey Data Release 2.Intensity-weighted Fourier coefficient (a4/a) was also derived for each sample galaxy.Our analysis shows that and between bulge and disk scale sizes.Isophotal shape parameter (a4/a) is not correlated with BIT and nB.Both bulge and disk components satisfy a color-magnitude relation.The k space Fundamental Plane analysis shows that galaxies with larger B/T tend to lie tighter and closer to the line of k1 k2=8 (the so-called "zone of avoidance") than the galaxies with smaller B/T.It indicates that existence of the disk component may lead to scatter of the distribution on the Fundamental Plane.Our analysis also shows that k1 k2 correlates with (y-r) color and B/T,but does not correlate with (a4/a) for early-type galaxies.The fitted parameters and other retrieved parameters used in this paper for all sample galaxies are available online. 相似文献
995.
In order to test the systematics of the Amati relation, 24 long-duration GRBs with available Eγ,iso, and Ep are separated into two subgroups according to the B-band luminosity of their host galaxies. The Amati relations in the two subgroups are found to be in agreement with each other within the uncertainties. Taking into account of the well established luminosity-metallicity relation of galaxies, no strong evolution of the Amati relation with the GRB's environmental metallicity is implied in this study. 相似文献
996.
997.
Bohai Sea oil spill model: a numerical case study 总被引:2,自引:0,他引:2
Zengan Deng Ting Yu Xiaoyi Jiang Suixiang Shi Jiye Jin Linchong Kang Feng Zhang 《Marine Geophysical Researches》2013,34(2):115-125
An operational Bohai Sea oil spill serving module (BSOSSM) that can provide users with trajectory and movement information of the released oil is developed for the purpose of informing mitigation of oil spill incidents in the Bohai Sea, China. BSOSSM is one of the serving modules that had been integrated in China digital ocean prototype system, a marine information platform for managing, displaying and disseminating all the data investigated by China 908 Program. The oil spill trajectory is calculated by an oil spill model (OSM), which serves as a component in BSOSSM. The impacts of wind, current, as well as Stokes drift on oil spill trajectory are studied by sensitivity experiments conducted using OSM. Simulation results indicate that wind forcing is the most important factor in controlling the oil trajectory at the sea surface in Bohai Sea, whereas current and Stokes drift play relatively less important roles. However, because the direction of waves generally follows that of the wind, Stokes drift does lead to an increase in oil drift and spreading velocity. Case studies of the Penglai 19-3 oil spill incident (June 2011) and Xingang oil spill (April 2005) demonstrate that OSM can generally reproduce the oil spreading, and is therefore capable of supporting the emergency response of future oil spills in the Bohai Sea through BSOSSM. 相似文献
998.
A hydraulic power unit(HPU) is the driving "heart" of deep-sea working equipment.It is critical to predict its dynamic performances in deep-water before being immerged in the seawater,while the experimental tests by simulating deep-sea environment have many disadvantages,such as expensive cost,long test cycles,and difficult to achieve low-temperature simulation,which is only used as a supplementary means for confirmatory experiment.This paper proposes a novel theoretical approach based on the linear varying parameters(LVP) modeling to foresee the dynamic performances of the driving unit.Firstly,based on the varying environment features,dynamic expressions of the compressibility and viscosity of hydraulic oil are derived to reveal the fluid performances changing.Secondly,models of hydraulic system and electrical system are accomplished respectively through studying the control process and energy transfer,and then LVP models of the pressure and flow rate control is obtained through the electro-hydraulic models integration.Thirdly,dynamic characteristics of HPU are obtained by the model simulating within bounded closed sets of varying parameters.Finally,the developed HPU is tested in a deep-sea imitating hull,and the experimental results are well consistent with the theoretical analysis outcomes,which clearly declare that the LVP modeling is a rational way to foresee dynamic performances of HPU.The research approach and model analysis results can be applied to the predictions of working properties and product designs for other deep-sea hydraulic pump. 相似文献
999.
Two aspects of deep mixing method, the difference relating strength gain in dry jet mixing (DJM, reagent powder introduced into the ground) and cement deep mixing (CDM, reagent slurry introduced into the ground), and prediction of unconfined compressive strength of cement stabilized marine clay, are discussed in this paper. The first part of this paper concentrates on the difference between DJM and CDM on strength gain, and suggests a guideline for DJM and CDM selection. An indicator in terms of water content ratio, which is defined as the ratio of water content to the liquid limit of the soil, is presented by statistical analysis from the laboratory and field test data as a guideline for the selection of DJM or CDM. Based on the laboratory test data, a mathematical model relating strength gain of cement stabilized marine clay to related variables is developed. A new simple index designated as total water-cement ratio, which is defined as the ratio of water weight in the soil-cement to the weight of cement in dry state, is proposed for interpretation of test data of soil-cement. The proposed method is then verified with available test data published by other different researchers. 相似文献
1000.
Zhuo Chen JinGen Deng Baohua Yu Haoyang Weng 《Marine Georesources & Geotechnology》2013,31(6):721-726
AbstractIn this article, based on the rheological consolidation model of deepwater shallow sediments, the artificial samples were made in laboratory. The feasibility of artificial samples was verified by electron microscopy scanning and triaxial experiments. Deepwater shallow sediments consolidation models mainly considers two points: (i) the change of permeability with time and temperature and (ii) the effect of rheology. The consolidation experiment of deepwater shallow sediments verifies the correctness of the model. It can be found that, the artificial and natural samples have the same physical and mechanical properties. And the physical properties of natural samples can be obtained by rheological consolidation model of deepwater shallow sediments. 相似文献