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281.
T.R.K. Chetty   《Gondwana Research》2010,18(4):565-582
New data from structural mapping and tectonic evaluation in the northern parts of the Eastern Ghats Mobile Belt (EGMB-north) involving the interpretation of satellite images, field traverses, critical outcrop mapping and kinematic studies of macro- as well as microstructures of the shear zone rocks together with the geometry and disposition of Gondwana basins led to, for the first time, the elucidation of post-Grenvillian structural architecture of the terrane. This helps in assessing the sequence of successive tectonothermal events that were responsible for the origin and progressive evolution of the Permo-Carboniferous coal bearing sediments along the Mahanadi rift that forms significant in the reconstruction models of east Gondwana.The composite terrane of high-grade metamorphic rocks (EGMB-north), strikes E–W in contrast to the regional NE–SW trend of the EGMB. The structural architecture obtained from this study is controlled by the boundary shear zones and associated link shear zones. The dextral kinematic displacements along the Northern Boundary Shear Zone (NBSZ) as well as the Mahanadi Shear Zone (MSZ) and Koraput–Sonapur–Rairakhol Shear Zone (KSRSZ) were derived from multi-scale field based structural observations. A N–S structural cross-section presents a crustal-scale ‘flower structure’ across the composite terrane exposing different domains displaying distinctive internal structures with widely varying different geological evolution history and strain partitioning, separated by crustal-scale shear zones. Deep seismic imaging and gravity signatures support ‘flower structure’ model. The pervasive first formed gneissic fabrics were continuously reworked and partitioned into a series of E–W, crustal-scale shear zones.The Neoproterozoic regional dextral transpressional tectonics along the shear zones and their repeated reactivation could be responsible for initiation and successive evolution of Gondwana basins and different episodes of sedimentation. Available geochronological data shows that the structural architecture presented here is post-Grenvillian, which has been repeatedly reactivated through long-lived transpressional tectonics. The composite terrane is characterized by all the typical features of an oblique convergent orogen with transpressional kinematics in the middle to lower crust. The kinematic changes from transpression to transtensional stresses were found to be associated with global geodynamics related to the transformation from Rodinia to Gondwana configuration.  相似文献   
282.
手持移动终端具有越来越强的计算与信息处理能力,本项研究拟将简化的3维地理信息与增强现实技术加以结合,在移动终端上构建一套增强地理信息系统(ARGIS),该系统可以利用3DGIS实时提供的数据,以及传感器数据,在用户利用手持移动终端获取环境视频或影像时,自动将一些不可见的地理信息增强到视频或影像之上,从而为用户在户外活动提供3维导航、信息查询,以及信息交换等应用服务。我们以北京大学校园为实验环境,开发了相应的原型系统,实验证明该方法实用可行,具有很好的发展前景。  相似文献   
283.
Three years of mobile barrier operations have been simulated with a hydrodynamic model to check the efficiency of the barriers in defending the city of Venice from flooding. The simulations have been carried out in the actual situation and with a sea-level rise of 30 and 50 cm. Moreover, the interference of the barrier operations with the ship traffic has been studied. It is found that without a security increment for the forecasted water levels, the mobile barriers cannot defend completely Venice from flooding due to the uncertainty in the forecast. With a security increment of 10 cm, the barriers work well in actual conditions but still cannot avoid flooding with a global sea-level rise. The interference with the ship traffic is acceptable under actual conditions but becomes prohibitive with a sea-level rise of 50 cm, when nearly two-thirds of the ship passages are blocked or delayed.  相似文献   
284.
等值线的绘制在自然科学领域上的应用十分广泛.本文介绍了一种在嵌入式终端PDA上绘制等值线的方法,该方法首先用逐点插入法生成Delaunay三角网,然后基于三角网追踪等值点,最后以MapX Mobile控件为图形平台,在Embedded Visual C 4.0环境下编程绘制等值线图,实现等值线图的放大、缩小、漫游、属性查询等GIS功能.继而以离散高程点为实验数据基于PDA环境绘制了等高线图,验证了上述方法的可行性.  相似文献   
285.
系统介绍了广播电视设备控制系统硬件基本结构及基本控制原理和系统管理软件包功能,对系统控制的实用性作了比较详细的分析和说明。该系统在电视台设备管理应用中具有很强的实用性和通用性。  相似文献   
286.
为解决测量工作中计算机与全站仪的数据通讯问题,在VC^ 6.0中使用串行通讯控件ActiveX实现了计算机与全站仪的数据通讯及生成成图软件所要求的坐标展点格式文件的方法,并给出了较为详细实用的实例程序,可在此基础上进行功能扩充,编写成全站仪和成图软件之间的通用接口软件。  相似文献   
287.
以GPS技术为核心、构筑中国LBS体系   总被引:1,自引:0,他引:1  
介绍了LBS的起源、定义、系统组成和相关技术,着重介绍了LBS在国外的发展和现状,以及与GPS技术的关系。  相似文献   
288.
利用河北省地震局华北测区流动磁测资料 ,分析了华北地区张北等几次较强地震前后地磁场的变化。结果认为 :震前异常的发展有扩大的趋势 ,震后或临震前基本恢复 ,异常持续时间一般半年以上 ,可作为中期异常 ,在此背景下进行短临预测追踪效果较好。  相似文献   
289.
A mobile mapping system (MMS) is the answer of the geoinformation community to the exponentially growing demand for various geospatial data with increasingly higher accuracies, captured by multiple sensors. As the mobile mapping technology is pushed to explore its use for various applications on water, rail, or road, the need emerges to have an external sensor calibration procedure that is portable, fast and easy to perform. This way, sensors can be mounted and demounted depending on the application requirements without the need for time consuming calibration procedures. A new methodology is presented to provide a high quality external calibration of cameras which is automatic, robust and fool proof. The method uses a portable, standard ranging pole which needs to be positioned on a known ground control point. While the literature focuses on solving the absolute orientation problem of the calibration, an automatic method to detect the calibration object is missing. Here, we present a mutual information based image registration technique for automatic sub-pixel localization of the ranging pole under realistic outdoor conditions. We include several robust error detection rules to allow the calibration to run without human intervention, giving as little outliers as possible, to ensure a correct calibration. Several tests are performed under various lighting and noise conditions which prove the methodology’s robustness.  相似文献   
290.
简要介绍了山东移动通信枢纽工程场地所处的地震环境、历史地震影响以及工程场地条件,利用地震危险性概率分析方法确定了50年超越概率为63%、10%和2%时工程场地平均土条件下的地震烈度、基岩地震动参数,并依据一维剪切波理论进行了场地地震反应分析,得到了具体的抗震设计参数。  相似文献   
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