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121.
基于网络的机器人跨平台远程实时控制 总被引:2,自引:0,他引:2
提出了一种基于网络的多层次结构的跨平台远程实时控制框架,它由智能与人机交互层、运动规划层、运动控制层和伺服控制层构成,并基于该框架完成了一套单机器人远程实时控制系统,进行了远程视觉控制试验。试验表明,该控制系统运行稳定,实时性强。 相似文献
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123.
Reena De S. G. Gaonkar B. V. Srirama Sagina Ram J. R. Kayal 《Journal of Earth System Science》2003,112(3):413-419
A 12-station temporary microearthquake network was established by the Geological Survey of India for aftershock monitoring
of the January 26th, 2001 Bhuj earthquake (M
w 7.6) in the Kutch district of Gujarat state, western India. The epicentres of the aftershocks show two major trends: one
in the NE direction and the other in the NW direction. Fault-plane solutions of the best-located and selected cluster of events
that occurred along the NE trend, at a depth of 15–38 km, show reverse faulting with a large left-lateral strike-slip motion,
which are comparable with the main-shock solution. The NW trending upper crustal aftershocks at depth <10 km, on the other
hand, show reverse faulting with right-lateral strike-slip motion, and the mid crustal and lower crustal aftershocks, at a
depth of 15–38 km, show pure reverse faulting as well as reverse faulting with right-lateral and left-lateral strike-slip
motions; these solutions are not comparable with the main-shock solution. It is inferred that the intersection of two faults
has been the source area for stress concentration to generate the main shock and the aftershocks. 相似文献
124.
U–Pb sensitive high resolution ion microprobe (SHRIMP) dating of zircons from charnockitic and garnet–biotite gneisses from the central portion of the Mozambique belt, central Tanzania indicate that the protolith granitoids were emplaced in a late Archaean, ca. 2.7 Ga, magmatic event. These ages are similar to other U–Pb and Pb–Pb ages obtained for other gneisses in this part of the belt. Zircon xenocrysts dated between 2.8 and 3.0 Ga indicate the presence of an older basement. Major and trace element geochemistry of these high-grade gneisses suggests that the granitoid protoliths may have formed in an active continental margin environment. Metamorphic zircon rims and multifaceted metamorphic zircons are dated at ca. 2.6 Ga indicating that these rocks were metamorphosed some 50–100 my after their emplacement. Pressure and temperature estimates on the charnockitic and garnet–biotite gneisses were obscured by post-peak metamorphic compositional homogenisation; however, these estimates combined with mineral textures suggest that these rocks underwent isobaric cooling to 800–850 °C at 12–14 kbar. It is considered likely that the granulite facies mineral assemblage developed during the ca. 2.6 Ga event, but it must be considered that it might instead represent a pervasive Neoproterozoic, Pan African, granulite facies overprint, similar to the ubiquitous eastern granulites further to the east. 相似文献
125.
Validation of Landslide Susceptibility Maps; Examples and Applications from a Case Study in Northern Spain 总被引:9,自引:3,他引:9
Remondo Juan González Alberto De Terán José Ramón Díaz Cendrero Antonio Fabbri Andrea Chung Chang-Jo F. 《Natural Hazards》2003,30(3):437-449
A procedure for validating landslide susceptibility maps wasapplied in a study area in northern Spain and the results obtained compared. Validationwas used to carry out sensitivity analysis for individual variables and combinationsof variables. The validity of different map-making methods was tested, as well as theutility of different types of Favourability Functions. The results obtained show thatvalidation is essential to determine the predictive value of susceptibility maps. Italso helps to better select the most suitable function and significant variables, thus improving the efficiency of the mapping process. Validation based on a temporal strategy makes it possible to derive hazard maps from susceptibility maps. 相似文献
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127.
Sarbari Ghosh Utpal Kumar De Atmospheric Science Research Department of Physics Jadavpur University Calcutta India Received April revised July 《大气科学进展》1997,(1)
AComparativeStudyoftheAtmosphericLayersbelowFirstLiftingCondensationLevelforInstantaneousPre-MonsoonThunderstormOcurenceatAga... 相似文献
128.
Rapid deforestation is a major problem throughout the tropical world. The conditions and the pace under which societies and economies of the Third World are currently evolving and growing, combined with the specificities of tropical forests, render the latter increasingly vulnerable. Among the major tropical areas of the world, Southeast Asia is perhaps the one where these conditions have had the most impact on the retreat of the forest cover over the last quarter of this century. This is illustrated through the presentation of two maps of the distribution of five basic forest formations in Southeast Asia circa 1970 and circa 1990. The maps are examined and compared, as well as confronted with statistical assessments of deforestation. Finally, the complex causes behind the retreat of the tropical forests as well as the implications of this retreat are briefly discussed. 相似文献
129.
130.