地下导线附加陀螺方位角的最佳位置

传统的地下导线测量,方位是通过单一轴线传递的,导线只测一个方位角,然而由于陀螺测量仪器的应用,可以直接测量导线其他边的方位角,一个加测的陀螺方位角不仅可以检查导线边之间方位和角度观测的质量,而且还可能降低贯通误差。等边直伸导线附加陀螺方位角最佳位置的确定,保证导线测员误差对贯通横向分量的影响最小。本文研讨附加陀螺方位角最佳位置是以隧道贯通中等边直伸导线为基础的。精度影响和数字实例分析表明,等边直伸导线附加陀螺方位角最佳位置在导线的第三节,与测量的精度无关。     

隧道地下导线控制测量的精度分析与陀螺仪的最优使用

本文论述了测量转折角和陀螺方位角误差对隧道贯通精度的影响公式。精度影响分析表明，每测５个转折角加测量１个陀螺方位角是最优的。     

超长小口径隧洞的贯通误差控制技术研究

我国规划了多项引水工程,超长隧洞(10～50 km)的贯通误差控制是急需解决的难题.通过多菱形单元的狭长形洞内控制网、适当加测高精度陀螺方位角的方法来满足贯通误差限差的要求,并利用基于统计试验法的控制网精度分析验证了洞内控制测量影响值.     

地下导线附加陀螺方位角的最佳位置

传统的地下导线测量，方位是通过单一轴线传递的，导线只测一个方位角，然而由于陀螺测量仪器的应用，可以直接测量导线其他边的方位角，一个加测的陀螺方位角不仅可以检查导线边之间方位和角度观测的质量，而且还可能降低贯通误差。等边直伸导线附加陀螺方位角最佳位置的确定，保证导线测量误差对贯通横向分量的影响最小。本文研讨附加陀螺方位角最佳位置是以隧道贯通中等边直伸导线为基础的。精度影响和数字实例分析表明，等边直伸     

雅砻江锦屏水电站交通辅助洞施工控制与精度分析

本文围绕雅砻江锦屏水电站辅助洞17.5 km交通隧道工程重点介绍洞内施工导线测量的精度,分析了其中两次复测结果产生较大偏差的原因,采用加测陀螺方位角的方法改善导线的点位精度,削弱旁折光等因素可能产生的误差影响,实测数据的处理结果与分析表明加测陀螺方位角大大提高了导线的精度和可靠性。     

加测一个陀螺方位角的支导线平差方法在青草沙原水过江管隧道地下导线测量中的运用

介绍了加测一个陀螺方位角的地下导线平差方法,根据上海青草沙过江原水管工程地下贯通导线测量中采用GYROMAT-2000型陀螺经纬仪加测一条地下导线边方位角的实例,论证了方法的正确性。     

地下贯通工程测量方案的优化理论和方法

地下贯通工程的控制测量导线多为加测陀累方位角的导线，本文讨论了贯通工程导线加测陀螺边的个数，位置，以及提高其可靠性，经济性的有关问题。     

地下导线测量对隧道横向贯通误差影响研究

由地下导线测量不同布网方案对隧道横向贯通误差影响计算公式,通过模拟计算,对比分析了不同布网方案对横向贯通误差的影响,并且分析了在支导线中加测陀螺方位角定向边的位置、定向精度对横向贯通误差影响关系。     

锦屏辅助洞施工控制网布设研究

针对锦屏辅助洞工程的施工控制网,在隧洞的贯通精度设计、洞外GPS网布设、洞内导线网设计、加测精密陀螺方位角、一、二等水准测量以及贯通误差影响值估算等方面进行了详细的讨论,取得了创新性的成果,在极其困难复杂的条件下,B洞以极小的误差精确贯通,可为类似工程提供参考。     

精密陀螺全站仪在城市综合地下管廊中的应用研究

随着地下管网建设的不断发展,在城市建造用于集中敷设电力、通信、广电、给排水、热力、燃气等市政管线的地下综合管廊,成为国家重点支持的民生工程。地下综合管廊的修建,给测绘工作者带来了新的挑战,如何将地面坐标基准精度传递至地下,确保管廊廊道的准确贯通是测量工作的关键。针对地下综合管廊的施工特点,本文介绍了几种适用于廊道修建的地下平面控制网布设方法,同时提出应用精密陀螺全站仪在地下导线中加测方位角的方法,分析加测陀螺方位角对贯通误差的影响规律,以起到优化地下导线,提高贯通精度的作用。     

阿克苏河-塔里木河水系水质污染遥感监测与评价

 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。     

Monitoring drought dynamics in the Aravalli region (India) using different indices based on ground and remote sensing data

The hard-rock hilly Aravalli terrain of Rajasthan province of India suffers with frequent drought due to poor and delayed monsoon, abnormally high summer-temperature and insufficient water resources. In the present study, detailed analysis of meteorological and hydrological data of the Aravalli region has been carried out for the years 1984–2003. Standardised Precipitation Index (SPI) has been used to quantify the precipitation deficit. Standardised Water-Level Index (SWI) has been developed to assess ground-water recharge-deficit. Vegetative drought indices like Vegetation Condition Index (VCI) and Temperature Condition Index (TCI) and Vegetation Health Index (VHI) have been computed using NDVI values obtained from Global Vegetation Index (GVI) and thermal channel data of NOAA AVHRR satellite. Detailed analyses of spatial and temporal drought dynamics during monsoon and non-monsoon seasons have been carried out through drought index maps generated in Geographic Information Systems (GIS) environment. Analysis and interpretation of these maps reveal that negative SPI anomalies not always correspond to drought. In the Aravalli region, aquifer-stress shifts its position time to time, and in certain pockets it is more frequent. In comparison to hydrological stress, vegetative stress in the Aravalli region is found to be slower to begin but quicker to withdraw.     

Landslide risk analysis between Giri and Tons Rivers in Himachal Himalaya (India)

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.     

Gravity Changes Before Large Earthquakes in China: 1998-2005

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...     

GNSS系统及其技术的发展研究

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.     

“4D”技术及其应用

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。     

Virtual Australia: its key elements – know,think, communicate

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.     

Toward seamless indoor-outdoor applications: Developing stakeholder-oriented location-based services

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.     

地理数据库的关系模型及其实现

本文从以图论观点分析地理实体入手,系统阐述了地理数据库关系模型的设计法和过程。作者于1984年4～9月间在微型机上设计建立了关系型地理数据库的实方验系统(RGDB)。该系统采用了本文提出的关系模型,采用了可动态扩库的子库组合结构,这种结构具有灵活性和提高空间利用率的优点。RGDB含有多种功能的数据操作命令,除了具有一般检索功能外,还能进行“开窗”选取和十分“自由”的映象选取。本文对RGDB系统的主要性能和实现途径作了扼要介绍。     

GIS空间数据的采集误差及其分析

本文详细阐述了GIS数据采集过程中的误差来源，重点分析了通过地图、遥感和摄影测量等方式采集数据所产生的误差及其特性，分析了其对GIS数据的影响与消减方法。