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天文测量中减弱大气折射影响的方法 总被引:1,自引:0,他引:1
大气折射是对天文测量精度影响较大的因素之一,至今无法将其完全消除,只能尽量减弱。因此,处理好大气折射改正,是提高天文测量精度的一项重要任务。文中分析了大气折射的特点.介绍了传统天文测量对大气折射的处理方法;研究并实现了新的处理大气折射的方法,给出了具体解算公式。新方法的应用,使天文测量的效率、精度都得以大大提高。 相似文献
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实时载波相位测量技术RTK(Real-time kinematic)是通过接收卫星发射的信号而进行数据处理,具有快速、全天候、高精度和无需通视的高新测量手段,能够实时地提供点位的三维坐标。高等级道路建设工程施工测量的基本任务是按照规范要求的精度和方法,将建筑物和构筑物的平面位置和高程放样到实地。在南邓(南阳至邓州)高速公路卧龙区英庄镇至新野县王集镇23.1千米的路段中线敷设中,应用GPSRTK技术,取得了较高的测量精度,实测点位与理论点位平面误差均在2厘米内,中桩高程最大误差2.2厘米,对保证道路建设工程质量起到了重要的基础保障作用。 相似文献
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本文讨论了精度可达被摄物体尺寸百万分之一的工业摄影测量。文中回顾了摄影测量网的设计,着重讨论了网的一级设计和二级设计之间的关系以及对不可补偿系统误差影响的削弱问题。文中还浅谈了摄影测量系统方面的问题。此外,还描述了一大型紧缩场反射开线的摄影测量网的优化设计过程,并总结了该结构后续的调校测量的结果,上述摄影测量的三维坐标精度达到了百万分之一的相对精度。 相似文献
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为避免RTK测量作业时对中杆倾斜引起的测量误差,提出球心拟合RTK测量方法,并利用该方法进行实验测量分析其测量精度,实验结果表明:(1)该法的测量精度受参与拟合的球面天线相位中心个数影响较大,当拟合点数大于8个时拟合结果较可靠;(2)该法的测量精度受对中杆倾斜角度的影响较大,当对中杆倾斜角度在30°时拟合精度较高。该方法将为特殊环境下RTK高精度作业提供借鉴参考,具有一定的工程应用价值。 相似文献
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山区带状GPS测量高程精度的探讨 总被引:1,自引:0,他引:1
本文介绍了某山区带状GPS测量控制网的布设、观测及数据处理,并着重对该网的高程拟合模型和已知点分布进行了探讨。结果表明:在保证必要的GPS高程测量精度的前提下,只需联测全网总点数1/4-1/6的水准高程点,并采用分段折线模型进行高程拟会,能够使峡谷带状GPS测量的高程达到±0.10m的精度。 相似文献
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航空重力测量中确定载体速度的静态试验 总被引:1,自引:0,他引:1
航空重力测量需要一定精度的导航信息,其中也包括载体的运动速度,用于计算厄特弗斯改正,本文作者参考文献[1][2]中的利用GPS多普勒频移观测值确定运动载体速度基本原理,自行研制了VAES(Velocity and Acceleration Esti-mation System)软件,用静态试验数据验证了理论的可靠性、软件的稳定性和该方法可以达到的精度。数据处理结果表明,载体水平速度的确定精度可达1-2cm/s,满足航空重力测量的精度要求。 相似文献
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在过去几年里,用GPS接收机进行大地测量,已能达到厘米级的精度.通常所用的接收机每台价值超过3万美元.然而现在低价接收机的出现(每台1万美元以内),改善了GPS测量的性能价格比:应用三台Magnavox公司产品MX4200D接收机作了静态测量的试验。每天观测1-2小时、基线距离为8—15公里,数据后处理应用Calgary大学的软件包SEMIKIN。所得到的成果用二种方法进行检验。一种方法是将该成果与以前用Trimble接收机取得的成果作比较,两者较差在10cm以内。另一种方法是将MX4200D接收机重复测量二天的计算成果进行比较,其较差小于3.5cm。在文中还评述了低价GPS接机在测绘仪器市场上的影响. 相似文献
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采用Landsat TM数据分析了阿克苏河—塔里木河断面水质污染状况,通过波段的DN值和常规监测数据建立能反映水质状况的
污染物监测模型。结果发现,将2000年常规监测数据代入模型后,与遥感数据的结果基本吻合| 重建阿克苏河—塔里木河的连续水体
污染变化曲线,得出污染物浓度随着远离上游而增加。 相似文献
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ZHAN F. Benjamin 《地球空间信息科学学报》2011,(1)
Although it is well known that coseismic gravity changes take place during an earthquake, previous research has not yielded convincing evidence demonstrating that significant gravity changes occur before large earthquakes. Furthermore, even if we suspect that gravity changes occur before large earthquakes, we have yet to demonstrate how to consistently observe these changes for useful earthquake forecast that would bring benefits to society. We analyzed ground gravity survey data obtained in 1998, 2000, 200... 相似文献
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Piyoosh Rautela Ramesh Chandra Lakhera 《International Journal of Applied Earth Observation and Geoinformation》2000,2(3-4)
The area around Sataun in the Sirmur district of Himachal Pradesh, India (falling between the rivers Giri and Tons; both tributaries of the Yamuna River) was studied for landslide vulnerability on behalf of the inhabitants. The study was made using extensive remote sensing data (satellite and airborne). It is well supported by field evidence, demographic and infrastructural details and aided by Geographic Information System (GIS) based techniques. Field observations testify that slope, aspect, geology, tectonic planes, drainage, and land use all influence landslides in the region. These parameters were taken into consideration using the statistical approach of landslide hazard zonation. Using the census data of 1991, vulnerability of the populace to the landslide hazard was accessed. As most of the infrastructure in the region is concentrated around population centres, population data alone was used for vulnerability studies. 相似文献
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GNSS系统及其技术的发展研究 总被引:3,自引:1,他引:2
阐述了国际上卫星导航系统的总体发展,对美、俄、欧、中的四大全球系统,以及相关的区域系统和增强系统进行了简单的介绍,研究分析了GNSS系统及其技术的发展趋势,同时分析了我国Compass全球系统面临的机遇和挑战,并提出了我国未来工作的建议. 相似文献
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“4D”技术及其应用 总被引:13,自引:0,他引:13
介绍“4D”(即数字地面模型、数字正射影像、数字栅格地图和数字线划地图)系列产品的生产流程、关键技术、及其在耕地保护、防灾减灾救灾和城市规划等方面的应用方法。 相似文献
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《International Journal of Digital Earth》2013,6(1):66-87
Abstract Virtual Australia is not a well-defined or agreed concept. This discussion paper conceptualises Virtual Australia as a ‘virtual [digital] model containing and representing all non-trivial objects and their contextual environment – from blue sky to bedrock – in real world Australia’. It describes a scenario for Virtual Australia, one or two decades from now, in which the locations and conditions of non-trivial objects and their environment are updated automatically through a combination of remote sensing and wireless communication technologies in support of a ‘Supranet’. It then examines the concept of the ‘Supranet’ – a pervasive information network based largely on wireless technology linking the physical world to a virtual model in real time – and develops and discusses three principal characteristics of the Supranet: the ability to have or collect specific information (know); the ability to process information (think); and the ability to communicate that information. If, in the near future, any or all non-trivial devices are to some extent able to know, think and communicate, the potential for object autonomy will be realised. 相似文献
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Toward seamless indoor-outdoor applications: Developing stakeholder-oriented location-based services
Kohei OGAWA Edward VERBREE Sisi ZLATANOVA Naohiko KOHTAKE Yoshiaki OHKAMI 《地球空间信息科学学报》2011,14(2):109-118
Location-Based Services (LBS),an emerging new business based on smartphone and mobile networks,are becoming more and more popular.Most of these LBSs,however,only offer non-seamless indoor/outdoor applications and simple applications without giving stakeholders the chance to play an active role.Our specific aim is to solve these issues.This paper presents concepts to solve these issues by expanding the Open Location Services Interface Standard (OpenLS) to allow seamless indoor/outdoor positioning and to extend the content of the services to include information recommended by stakeholders. 相似文献