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针对既有铁路复测全站仪棱镜对中整平精度差、效率低的问题,设计制作了既有铁路复测全站仪棱镜专用对中整平装置,通过本装置的强制对中卡,完成测量棱镜在铁轨中线上的强制对中,再利用本装置的整平杆和双气泡水平夹实现测量棱镜的整平,本装置拆卸方便,不损伤棱镜本身结构,且同时适用于既有铁路复测中其他设备、设施测量的对中整平作业,在既有铁路复测中取得了良好的效果。 相似文献
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柳南铁路既有基础平面控制网（C PⅠ）无法满足《高速铁路工程测量规范》的要求,需要进行变更测量。分析了既有CPⅠ存在的问题,对柳南铁路变更CPⅠ的观测方法及数据处理过程进行了研究,并与既有CPⅠ成果进行了对比分析。变更后的CPⅠ可以满足工程设计、施工及运营监测的要求。 相似文献
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本文介绍了采用座标法编制铁路既有曲线计算软件的原理和方法 ,本软件功能齐全 ,操作简便 ,经实践检验证明 ,本软件对铁路既有曲线测量具有理论严密 ,精度、效益高和成果美观的特性 ,值得推广应用 相似文献
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介绍了使用海拉瓦摄影测量工作站的SOCETSET软件针对我国铁路航测的实际情况 ,进行空三加密、制作DEM、正射影像和三维立体景观图的一些体会和感受。通过实际生产表明 ,在既有铁路航测生产中应用Helave数字摄影测量工作站 ,产生了明显的社会和经济效益。这是既有铁路航测的新产品 ,使用户更逼真 ,直观地观看铁路运输现场 ,深受铁路局的欢迎。 相似文献
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本文谈论了既有铁路航测数字化测图与解析摄影测量相比的特点。讲述了在其数字化测图的各个方面 ,多出优质产品的质量要求 相似文献
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本文通过津浦铁路航测、复测生产，叙述了航测、电子计算技术在既有铁路测量中的应用。由于这些先进技术的应用，导致测量工效、产品质量、测绘成果都产生了较大变化，取得很高的效益。 相似文献
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针对传统既有铁路曲线重构方式图形化交互程度低,无法实现既有铁路图形和属性数据的统一管理,从而导致曲线重构步骤繁琐的问题,利用GIS建立了既有铁路曲线重构系统,实现了既有铁路图形和属性数据的一体化管理、数据查询以及既有铁路正交最小二乘曲线重构.计算实例表明,该图形化作业方式人机交互方便、操作简单、效率高,能快速实现既有铁... 相似文献
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Positions and proper motions obtained from observations by the very large array (VLA) and the multi-element radio-linked interferometer
network (MERLIN) are used to establish the link of the Hipparcos Celestial Reference Frame (HCRF) to the International Celestial
Reference Frame (ICRF). The VLA and MERLIN data are apparently the latest ones published in the literature. Their mean epoch
at around 2001 is about 10 years after the epoch of the Hipparcos catalogue and, therefore, the data are considered suitable
to check the Hipparcos link established at epoch 1991.25. The parameters of the link, i.e., the angles of frame orientation
and the angular rates of frame rotation, are estimated by fitting these parameters to the differences of the optical and radio
positions and proper motions of stars common to the Hipparcos catalogue and the VLA and MERLIN data. Both the estimates of
the angles of orientation and the angular rates of rotation show nearly consistent but insignificant results for all samples
of stars treated. We conclude that not only the size of the samples of 9–15 stars is too small, but also that the accuracy
of the radio positions and, above all, of the radio proper motions is insufficient, the latter being based on early-epoch
star positions of low accuracy. The present observational data at epoch 2001 suggest that maintenance of the Hipparcos frame
is not feasible at this stage. 相似文献
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Anko Brner Lorenz Wiest Peter Keller Ralf Reulke Rolf Richter Michael Schaepman Daniel Schlpfer 《ISPRS Journal of Photogrammetry and Remote Sensing》2001,55(5-6)
The consistent end-to-end simulation of airborne and spaceborne earth remote sensing systems is an important task, and sometimes the only way for the adaptation and optimisation of a sensor and its observation conditions, the choice and test of algorithms for data processing, error estimation and the evaluation of the capabilities of the whole sensor system.The presented software simulator SENSOR (Software Environment for the Simulation of Optical Remote sensing systems) includes a full model of the sensor hardware, the observed scene, and the atmosphere in between. The simulator consists of three parts. The first part describes the geometrical relations between scene, sun, and the remote sensing system using a ray-tracing algorithm. The second part of the simulation environment considers the radiometry. It calculates the at-sensor radiance using a pre-calculated multidimensional lookup-table taking the atmospheric influence on the radiation into account. The third part consists of an optical and an electronic sensor model for the generation of digital images. Using SENSOR for an optimisation requires the additional application of task-specific data processing algorithms.The principle of the end-to-end-simulation approach is explained, all relevant concepts of SENSOR are discussed, and first examples of its use are given. The verification of SENSOR is demonstrated. This work is closely related to the Airborne PRISM Experiment (APEX), an airborne imaging spectrometer funded by the European Space Agency. 相似文献
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DanteSalvini 《地球空间信息科学学报》2002,5(1):18-21
One type of aerial cableway consists of a continuous cable,which works at the same time as carrying cable and drawing cable.This kind of cableway is supported by many towers,which divide the total length in linear sections.even small deviations from the planed layout can increase the strain of the cable and the danger of derailments.The deviations of the position of the towers from the planed layout are due to local sliding or sinking of the foundation or other mechanical movements.Up to now the axis of the cableways were periodically measured by traditional methods. The goal of this project is to demonstrate the possibility of measuring the axis of a cableway with GPS techniques,while the cable is moving.The results show that the proposed measuring device provides precise results in a simple and reliable way. 相似文献
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This paper provides a review of ground-based SAR (GBSAR) interferometry for deformation measurement. In the first part of the paper the fundamentals of this technique are provided. Then the main data processing and analysis stages needed to estimate deformations starting from the GBSAR observations are described. This section introduces the two types of GBSAR acquisition modes, i.e., continuous and discontinuous GBSAR, and reviews the different GBSAR processing and analysis methods published in the literature. This is followed by a discussion of the specific technical aspects of GBSAR deformation measurement. A section then summarizes the pros and cons of GBSAR for deformation monitoring. The last part of the paper includes two reviews: one concerning the GBSAR systems described in the literature, including non-strictly SAR systems and a second one addresses the main GBSAR applications. 相似文献
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The monitoring of different crops (cultivated plots) and types of surface (bare soils, etc.) is a crucial economic and environmental issue for the management of resources and human activity. In this context, the objective of this study is to evaluate the contribution of multispectral satellite imagery (optical and radar) to land use and land cover classification.Object-oriented supervised classifications, based on a Random Forest algorithm, and majority zoning post-processing are used. This study emerges from the experiment on multi-sensor crop monitoring (MCM'10, Baup et al., 2012) conducted in 2010 on a mixed farming area in the southwest of France, near Toulouse. This experiment enabled the regular and quasi-synchronous collection of multi-sensor satellite data and in situ observations, which are used in this study. 211 plots with contrasting characteristics (different slopes, soil types, aspects, farming practices, shapes and surface areas) were monitored to represent the variability of the study area. They can be grouped into four classes of land cover: 39 grassland areas, 100 plots of wheat, 13 plots of barley, 20 plots of rapeseed, and 2 classes of bare soil: 23 plots of small roughness and 16 plots of medium roughness. Satellite radar images in the X-, C- and L-bands (HH polarization) were acquired between 14 and 18 April 2010. Optical images delivered by Formosat-2 and corresponding field data were acquired on 14 April 2010.The results show that combining images acquired in the L-band (Alos) and the optical range (Formosat-2) improves the classification performance (overall accuracy = 0.85, kappa = 0.81) compared to the use of radar or optical data alone. The results obtained for the various types of land cover show performance levels and confusions related to the phenological stage of the species studied, with the geometry of the cover, the roughness states of the surfaces, etc. Performance is also related to the wavelength and penetration depth of the signal providing the images. Thus, the results show that the quality of the classification often increases with increasing wavelength of the images used. 相似文献
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随着城市面貌日新月异,地下管网的建设也在持续推进,作为城市的地下“神经网络”,全天24 h保障城市的正常运转和发展。本文以实现城市管网管理系统的高可用、无插件、智能化为目标,采用“地上地下一体”“二三维一体”的设计理念,研究基于WebGL的三维智慧管网系统的关键技术,实现了管线设施管理的信息数字化、空间化与图形化。 相似文献
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以滑坡蠕变阶段坡体的蠕变会引起环境条件的改变，进而影响植被生长状况的野外考察客观现实为依据，提出一种间接监测滑坡变化的新方法。利用高分辨率光学遥感技术，对滑坡蠕变阶段遥感影像上坡体上覆植被的异常特征进行判识，建立遥感影像上植被异常与滑坡蠕变的关系，反映滑坡的演化过程，弥补GPS技术、InSAR技术及部分地面监测手段在地势高、地形陡峭、植被茂盛等条件下监测工作的不足，为后续的滑坡预测研究提供帮助。以植被覆盖度较高的新磨村山体高位滑坡为例，首先，对研究区域进行分区；其次，计算各分区的植被覆盖度；最后，利用植被覆盖度分析遥感影像上的植被异常与滑坡蠕变的关系，并根据滑后遥感影像和实地考察情况进行验证。结果显示，2014年—2016年，滑坡的主要物源区、变形体上方细长局部崩滑区和泉眼及冲沟周边的植被覆盖度出现明显的下降，即随着滑坡发生时间的临近，植被受滑坡蠕变的影响变大，植被生长状况变差；而且随着距裸地等滑坡风险较大区域的距离增大，植被受滑坡蠕变的影响变小，植被生长状况变好。这表明，植被异常与滑坡蠕变存在明显的时空相关性，体现了滑坡蠕变阶段遥感影像上植被异常与滑坡蠕变的内在联系，反映了滑坡逐步失稳的演化过程，为进一步预测滑坡的发生提供依据。 相似文献
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随着移动定位、移动GIS与物联网等技术的不断发展,动态交通信息的服务能力和服务水平不断提升,对数据管理效率提出了更高要求。本文将本体应用到交通GIS中,借助本体概念层次结构和语义扩展等特性来组织和分析动态交通数据：首先应用本体论的理论和方法,从交通本体的层次模型出发,构建一个简单的交通应用本体;其次以实例的形式给出交通信息本体的系统应用框架;最终就动态交通信息本体实现与应用进行进一步论述。大量实测的试验数据结果表明,本文方法可解决交通信息领域中的多专题动态信息综合管理问题,促进交通信息管理与服务的提升。 相似文献
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GridGNSS--网格化全球卫星导航系统 总被引：3，自引：0，他引：3
计算机网络技术的发展已经使全球的信息资源实现网络互联和页面浏览,新一代的基于IPv6的IP地址方案的实施,将可以满足全球几乎任意的资源连接互联网的需要。随着移动通讯技术的发展,移动互联网和移动IP技术可以使移动用户通过网络实现全球资源的互联和访问。因此,对于通过全球卫星定位系统进行移动目标定位的用户,可以通过移动网络的方式实现传统的数据传输和通讯。随着新一代互联网络的的发展,WebService成为全球信息发布的最主要的平台,基于WebService的GNSS综合信息发布可以实现全球GNSS资源和信息的访问,计算机网格的出现为全球GNSS计算提供技术支持,本文基于网格技术,提出了GNSS网格和GridGNSS的概念,对GridGNSS的功能和研究内容进行了详细分析,并对GridGNSS的实现过程和应用进行了阐述。 相似文献
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根据系统空间数据结构的特点 ,提出了图块_实体数据模型 ,有效地解决了对空间信息操作的复杂性 ,有利于施工中空间数据的动态更新和维护。该系统的空间数据结构为相关信息系统建立适宜的空间数据结构提供了一条可行的途径。 相似文献