共查询到20条相似文献，搜索用时 171 毫秒
1.
????·??Ч??????????????????????·??Ч?????????????????????????????????????????·??Ч?????г????????????????????????????????????????????????????б????о????????????????????????г?????????·??Ч????з?????????е????????????????????г???????? 相似文献
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����DINSAR��2001������ɽ����8.1��������α�̽�� 总被引：9，自引：9，他引：0
2001??11??14????????????????8.1????????????????400 km???????,????????????????е??????????????????ERS??2 SAR?????????SRTM DEM???????????·????·???????洦????????????????α?????????????:?????????????????????????DEM????·???????????????????;??????????????????????????????????? 相似文献
3.
GPS��̬���β����еĶ�·��ЧӦ�����о� 总被引：6，自引：4，他引：2
?????????Χ??????????????GPS??·??Ч????к??????????????????β????е?GPS??·??Ч?????????????????????????????顣???????????????μ???е??·??Ч?????????г??????????????????????????????????????????????????????????????????????????????????????????t????????????????????·??Ч??????????????GPS???????????????30%????? 相似文献
4.
??????????????????·??GPS????????????????1 000 kV?????????·?????????????·?????????????????????·??????????????????￡?????GPS?????????????????????GPS???????й????????TEQC????????????????????μ?????????P1??P2??·????L1??L2????????????????????????GPS????????????????????????????????????????????·????????λ??GPS????δ????????????? 相似文献
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YRY�����Ӧ�������ݲɼ��ĸ߾���ʵ�� 总被引：1，自引：1，他引：0
??????????????????YRY????????????????????????6λ???????????????24λ??-????ADC ADS1201?????????????????·??????????????Χ??????????????????????????????????????????????????????????????????????????????Ч???? 相似文献
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??????COMPASS???????????COMPASSα?????????????????????????????4GEO+5IGSO????????COMPASSα????λ???????????????COMPASSα???·??Ч???????????0??3 m???仯???侫???0.3??0.7 m??????????????·??Ч??????????С??GEO??????????·??Ч??????????????С??IGSO?????COMPASSα????λ?????RMS????N??E??U?????????3.33??3.45??8.84 m?? 相似文献
7.
ˮƽ���ϵͳ���Զ���ƽ�����о� 总被引：1，自引：0，他引：1
?????????????????????????3????????????飬??4????????????????????????????????????·???? 相似文献
8.
����GPS���߽�������ͳ�Ʒ��� 总被引：1，自引：0，他引：1
??????????????????TIKHONOV??????????GPS?????????????????????????????????ε??????????о????????????????????????????????????????????????????????????????????????????????????У?????????з??????Eviews???????????????е????????????????????????ó??????1?????????????????????С??1 mm???????????????????????????????е???????????2????????????????5 mm?????????????????????3???????????X????Y??????н???????????????????????????????????????????????????·??Ч???4???????????Z???????????????????·????Z??????С?? 相似文献
9.
��ά�ռ����ά�ռ��߲���ת����������·��� 总被引：6，自引：1，他引：5
????????????δ?????????????????????????????????·?????????????????????????????????????????????????????????÷?Χ???ó?????:????γ??????Χ??С??8???,??x??y???????????????1 cm??????????侫???????γ??(?????γ??)??Χ????С?????????? 相似文献
10.
????????????????????????????????????????????????IPSO??????????????·?????IPSO????????????????????????????б????????????????????????????????????????????????PSO?????????????????????????????????????????????????LAMBDA????????????????????·??????п??????????????????????????????????ü???? 相似文献
11.
SUN Jilin ) )* XU Delong ) and GU Dejun ) ) Physical Oceanography Laboratory Ocean-Atmosphere Interaction Climate Laboratory Ocean University of China Qingdao P.R.China) Institute of Tropical Meteorology Guangzhou P.R.China 《中国海洋大学学报(英文版)》2006,5(3):200-206
1Introduction Theglobalclimatechangehasbeenoneoftheprob lemschallengingtheworldinrecentyears.TheweatherandclimateonEarthhasbeeninvariationontimescalesfromseasonaltomillennialorevenlonger.ResearchesonvariationsofweatherandclimateintheNorthernHemispherehave… 相似文献
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????1992??11???2007??5?μ???????????????????????????仯???????????????1???????24~42???μ???????Я???????????ENSO?????2??SLA_2442?????????????????????????????????????????????????????????????????3?????????У????????????SLA_2442?????????·??????O???Σ??????????????,??γ????????λ??????9.86??N??8??S?????? 相似文献
14.
Influence of temperature and frequency on microwave dielectric properties of lunar regolith simulant
EDWARD Matthew Osei Jnr 《中国地理科学(英文版)》2011,21(1):94-101
The dielectric constant of the lunar regolith can directly influence the reflection coefficient and the trans-mission coefficient of the Moon′s surface, and plays an important role in the Moon research. In order to study the di-electric properties of the lunar regolith, the lunar regolith simulant was made according to the making procedure of the CAS-1 simulant made by Chinese Academy of Sciences. Then the dielectric constants of the lunar regolith simulant were measured with 85070E Aiglent Microwave Network Analyzer in the frequency ranging from 0.2 GHz to 20.0 GHz and at temperature of 25.1℃, 17.7℃, 13.1℃, 11.5℃, 9.6℃, 8.0℃, 4.1℃, -0.3℃, -4.7℃, -9.5℃, -18.7℃, -27.7℃, and -32.6℃, respectively. The Odelevsky model was employed to remove the influence of water in the air on the final effective dielectric constants. The results indicate that frequency and temperature have apparent influences on the dielectric constants of the lunar regolith simulant. The real parts of the dielectric constants increase fast over the range of 0.2 GHz to 3.0 GHz, but decrease slowly over the range of 4.0 GHz to 20.0 GHz. The opposite phenomenon occurs in the imaginary parts. The influences of the frequency and temperature on the brightness temperature were also estimated based on the radiative transfer equation. The result shows that the variation of the frequency and temperature results in great changes of the microwave brightness temperature emitting from the lunar regolith. 相似文献
15.
为了阐明地震滑坡的运动特性并对其进行致灾距的预测,基于遥感影像解译和野外调查数据,借助经验公式法,分析了汶川地震滑坡水平最大运移距离L与前后缘高差H之间的相关性,给出了经验公式;探讨了不同滑坡之间滑程的差异与异常。结果表明:若已知H,可用L=aH+b或L=aHb对总位移进行预测初探;将视摩擦系数H/L=0.45作为汶川地震高速远程型滑坡的上限较合适;滑坡体积、源区破裂面积与L呈正相关,与H/L呈负相关;地震滑坡易发生在山脊线平行于断裂带、垂直于地震波传播方向的山体两侧;崩塌型滑坡易发前后缘高差范围在10~100m之间,大型高速远程型滑坡易发前后缘高差大于200m;滑坡源区易发坡度分布在25°51°之间,滑床坡降变化范围为0~58°,高速远程型滑坡的滑床坡降主要在8°20°之间;分析认为滑程差异和异常是距离效应、能量传递与岩体挡板效应、滚动润滑与气垫效应、体积与破裂面积效应、地质因子、地形因子、颗粒级配与颗粒流效应等因素综合作用的结果,考虑上述因素有益于滑坡-碎屑流致灾距的预测分析。 相似文献
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Submarine landslides occur frequently on most continental margins. They are effective mechanisms of sediment transfer but also a geological hazard to seafloor installations. In this paper, submarine slope stability is evaluated using a 2D limit equilibrium method. Considerations of slope, sediment, and triggering force on the factor of safety (FOS) were calculated in drained and undrained (Φ=0) cases. Results show that submarine slopes are stable when the slope is <16° under static conditions and without a weak interlayer. With a weak interlayer, slopes are stable at <18° in the drained case and at <9° in the undrained case. Earthquake loading can drastically reduce the shear strength of sediment with increased pore water pressure. The slope became unstable at >13° with earthquake peak ground acceleration (PGA) of 0.5 g; whereas with a weak layer, a PGA of 0.2 g could trigger instability at slopes >10°, and >3° for PGA of 0.5 g. The northern slope of the South China Sea is geomorphologically stable under static conditions. However, because of the possibility of high PGA at the eastern margin of the South China Sea, submarine slides are likely on the Taiwan Bank slope and eastern part of the Dongsha slope. Therefore, submarine slides recognized in seismic profiles on the Taiwan Bank slope would be triggered by an earthquake, the most important factor for triggering submarine slides on the northern slope of the South China Sea. Considering the distribution of PGA, we consider the northern slope of the South China Sea to be stable, excluding the Taiwan Bank slope, which is tectonically active. 相似文献
18.
The three dimensional structure of the western boundary current east of the Vietnam coast was determined from measurements
by Argo profiling floats which deployed near the east of the Vietnam Coast in October 2007. The trajectories of the Argo floats
provided robust evidence that there does exist southward flowing current along the Vietnam coast. The southward current begins
at about 15°N, 111°E, flowing along the 1 000 m isobath and extending to 5°N south. The estimated surface and parking depth
velocities obtained from the floats suggest that this southward current can extend to 1 000 m depth. The mean surface velocity
of the western boundary current is about 49 cm/s, with the maximum speed exceeding 100 cm/s occurring at 11.6°N, 109.5°E in
the direction of 245°. The mean parking depth (1 000 m) velocity is 12–16 cm/s with the maximum speed of 36 cm/s occurring
at 12.1°N, 109.7°E in the direction of 239°. 相似文献
19.
Mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradation 总被引：2，自引：0，他引：2
The mass-front velocities of granular flows results from the joint action of particle size gradations and the underlying surfaces.However,because of the complexity of friction during flow movement,details such as the slope-toe impedance effects and momentum-transfer mechanisms have not been completely explained by theoretical analyses,numerical simulations,or field investigations.To study the mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradations we conducted model experiments that recorded the motion of rapid and long-runout rockslides or avalanches.Flume tests were conducted using slope angles of 25°,35°,45°,and 55° and three particle size gradations.The resulting mass-front motions consisted of three stages:acceleration,velocity maintenance,and deceleration.The existing methods of velocity prediction could not explain the slowing effect of the slope toe or the momentum-transfer steady velocity stage.When the slope angle increased from 25° to 55°,the mass-front velocities dropped significantly to between 44.4% and59.6% of the peak velocities and energy lossesincreased from 69.1% to 83.7% of the initial,respectively.The velocity maintenance stages occurred after the slope-toe and mass-front velocity fluctuations.During this stage,travel distances increased as the angles increased,but the average velocity was greatest at 45°.At a slope angle of 45°,as the median particle size increased,energy loss around the slope toe decreased,the efficiency of momentum transfer increased,and the distance of the velocity maintenance stage increased.We presented an improved average velocity formula for granular flow and a geometrical model of the energy along the flow line. 相似文献
20.
The principal variability patterns (EOF) of the anomalies of total heat transfer from ocean to atmosphere computed from 30
years' monthly averaged data over the North Pacific Ocean (20°–60°N) showed variability was dominated by two patterns: a bipolar
pattern and a dominantly positive or negative pattern depending on the sign of the time series coefficients. The atmosphere
contributes greatly to the marine heating anomalies in most of the North Pacific in all seasons. In winter, a positive feedback
is formed between the Aleutian Low and the marine heating anomalies; in summer, the marine heating anomalies are controlled
by the heating on the Qinghai-Tibetan Plateau. Both patterns have a winter correlation with the Southern Oscillation Index.
Contribution No. 1534 from the Institute of Oceanology, Academia Sinica 相似文献