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991.
3S技术在土地利用中的应用 总被引:1,自引:0,他引:1
针对目前我国土地普遍存在的土地环境问题、原生土地问题、次生土地土地问题和社会土地问题,提出了应用“3s”技术进行辅助决策,以解决这些问题。 相似文献
992.
中国石油广西石化1000万t/a炼油项目参与各方人员共同使用p3e/c软件编制完成了该项目基础设计、详细设计、采购、施工、试车等整个项目各装置各级网络计划。阐述了应用p3e/c软件在该项目计划、进度与费用控制实战中的计划目标的建立、控制与应用,旨在为同类项目在计划、进度与费用控制上起到抛砖引玉的作用。广西石化1000万t/a炼油项目的计划管理工作吸取了国际上先进的项目管理经验及方法,全面采用了p3e/c软件作为计划管理工具,并充分结合了目前国内施工管理的实际水平,探索出国内大型新建炼油项目计划管理工作的新路,使广西石化1000万t/a炼油项目的计划管理工作处于国内领先的位置。 相似文献
993.
简要介绍了如何基于CAD平台开发构面软件,实现3DSMAX快速建模,提出了一套完整的思路,总结了实现快速建模的技术路线,并用实例进行了验证,达到了预期的3维效果,为实现数字城市和数字乡镇的3维景观显示提供了切实可行的方法,起到了抛砖引玉的作用。 相似文献
994.
Seismic performance of exterior beam–column subassemblages of reinforced concrete structure designed and detailed on the basis of the provisions of Eurocode and Indian Standards at different stages of their evolution is evaluated. Performance of the subassemblages designed and detailed according to the three different stages of codal evolution (gravity load design, ‘Nonductile’, and ‘Ductile’) is evaluated through analytical formulations and experimental investigations. In the ‘NonDuctile’ specimens, it has been observed that the shear distortion and degradation in stiffness and strength are significantly high. Performance of the ‘Ductile’ specimens based on Eurocode and Indian Standards is almost similar in terms of strength and stiffness degradation. Nevertheless, the specimen designed on the basis of Indian Standard shows higher energy dissipation at a given drift ratio. In the analytical study, shear and flexural failure of members of subassemblage and shear failure of the joint are considered as possible modes of failure of the beam–column subassemblage. For evaluating the shear strength of the joint region, a soften strut‐and‐tie model is used. Analytically obtained strengths based on the failure criteria of different components of the specimens have been first validated with experimental results and then used to determine the strength of the specimens. The investigation could indicate even the mode of failure at local level. It is utmost important to mention here that even the ductile specimens dissipate most of the energy through the development of damage in the joint region, which is neither desirable nor safe for the stability of whole structure. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
995.
996.
Christoph Siart Markus Forbriger Erich Nowaczinski Stefan Hecht Bernhard Höfle 《地球表面变化过程与地形》2013,38(10):1135-1147
A multi‐method research design based on terrestrial laser scanning, GIS, geophysical prospecting (electrical resistivity tomography, refraction seismics) and sedimentology is applied for the first time to investigate enclosed karst depressions in an integrated way. Fusing multi‐resolution surface and subsurface geodata provides profound insights into the formation, geometry and geomorphologic processes of dolines. The studied landforms, which are located in the Dikti Mountains of East Crete, are shown to be filled by loose sediments of thicknesses of up to 30 m that mainly consist of fine‐grained material overlying solid bedrock at depths below 35 to 45 m. By combining subsurface observations with geomorphometric calculations, local doline genesis can be traced back to initial collapse of fractured bedrock followed by subsequent infilling with colluvials. In order to define crucial methodological requirements and guidelines for data fusion, both the impact of different elevation models and the influence of data resolution are assessed. Surface volumes of depressions derived by the digital surface model are 7–21% higher than the results obtained from the terrain model due to vegetation. Similarly, estimates of infill volume calculated on the basis of geophysical outcomes and elevation data differ by up to 13%. Calculations of the landforms' current volumes (i.e. total surface and subsurface volume), however, are fairly insensitive to raster resolution. Hence, the distinct geomorphologic properties of landforms (e.g. shape, terrain roughness, slope inclination) substantially determine the geomorphometric analysis of both surface and subsurface data. As shown by the findings, data fusion to integrate digital terrain, geophysical and sedimentological datasets of varied resolutions benefits geomorphologic studies and helps provide a comprehensive image of landforms. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
997.
Non-uniform ground motions are generated based on a single record available at a site and seismic wave scattering analysis. The Chino Hills 2008 earthquake records at the Pacoima Dam site are used to indicate the accuracy of the method. Dynamic analysis of the Pacoima dam-reservoir-foundation under uniform and non-uniform ground motions is carried out using the EACD-3D2008 software, and the results are compared to recorded responses at different locations on the dam. There is good agreement between computed and recorded displacements of the dam for non-uniform excitation. For uniform excitation, the displacements are underestimated in comparison with those obtained from recorded excitation. Significant intensification of stresses, especially near the foundation, and different patterns of stress distribution are observed for non-uniform excitation in comparison with uniform excitation. For uniform excitation maximum stresses occur in the crown cantilever near the crest, but for non-uniform excitation the maximum stresses occur along the sides and near the foundation. 相似文献
998.
Abstract A two-dimensional (2D) hydrodynamic assessment of the Nile swamps in southern Sudan has been carried out using DHI MIKE 21 software based on a ground referenced and corrected Shuttle Radar Topography Mission (SRTM) digital elevation model. The model was set up and calibrated using available historical information as well as newly measured data. The results show the model capable of representing the hydraulic conditions in the swamps, allowing the assessment of different flow conditions and their effects on the swamp. The study has established water-level gradients, flow directions and velocities in the swamp, as well as on the seasonal flood plains, and describes the importance of evapotranspiration for losses in the system. Citation Petersen, G. & Fohrer, N. (2010) Two-dimensional numerical assessment of the hydrodynamics of the Nile swamps in southern Sudan. Hydrol. Sci. J. 55(1), 17–26. 相似文献
999.
We applied analysis AVO with partial stacking to an onshore gas field in order to detect gas at the top of the Ciénaga de Oro formation (FCO), by using seismic gathers of the Güepajé-3D project. The technique was supported by petrophysical analysis of the Ayombe-1 well.The sensitivity of seismic response to changes in the saturating fluid was evaluated by fluid substitution technique in an interval of the Ayombe-1 well. As a result, a class I AVO anomaly at the top of the FCO was observed, even though the gas and water responses were similar. After applying AVO with partial stack technique at the top of FCO, AVO class I anomalies were observed in the Ayombe-1 and Güepajé-1 gas wells and none in the dry Güepajé-3 well. In spite of being reported with gas, the results in the Güepajé-2 well indicated any to an incipient class I anomaly related to a weak seismic response associated to gas.When the technique was applied to the seismic volume of the Güepajé-3D Project, a map of the direct gas indicator was obtained. The map shows a high correlation with the structural surface at top of FCO. Lithic factors such as compaction, cementation and carbonate overlaying the FCO and variable thickness of partial and full saturated layers, may cause anomalies in zones unlikely to contain gas. 相似文献
1000.
邓开艳 《测绘与空间地理信息》2013,36(7):136-138,141
探讨了GeoGlobe3维GIS技术在基础测绘成果客户选图服务中的应用,主要包括系统框架设计和具体功能。 相似文献