矿区简易CORS系统的建立及应用

针对当前GPS技术广泛应用于变形监测领域的趋势和矿区开采沉陷监测的特点,从适用性、经济性出发,阐述在矿区开采沉陷地表移动研究中CORS系统的建立,经过实践检验,为CORS系统的建立使用提出参考意见。     

采样数据密度及栅格尺寸对高程中误差的影响分析

利用全数字摄影测量得到的高精度点数据,获取不同密度的点数据,建立基于ANUDEM和TIN方法的两种DEM,比较两种DEM的高程中误差,分析数据密度、栅格尺寸与高程中误差的关系。研究结果表明,建立1∶100 00比例尺,具有高程中误差2m左右、栅格尺寸5m以下的ANUDEM,需要的点密度水平为大于7 000个/km2,而TINDEM则为8 500个/km2。同时,当栅格尺寸小于20m、数据密度介于7 000～9 400个/km2时,无论是ANUDEM还是TINDEM,高程中误差都处于一个较稳定的状态。     

利用高分辨率航天遥感影像实现城市3维可视化

利用高分辨率遥感影像提取地物数据，并采取面向对象的空间数据模型对数据进行管理，使用虚拟现实技术对城市景观进行3维重建，然后利用有理函数数学模型表示遥感影像与地面之间的构像关系。使用纹理映射技术，构建具有高度真实感的城市3维景观图。     

Study on Polarized Spectral Characteristics of Soil with Different Water Content

Moisture is one of the important parameters in soil polarized spectrum. It has great significance in soil remote sensing band selection and image interpretation; it also provides the information for soil investigation and analysis on physical and chemical properties. In this paper we tested and analyzed the soil polarized spectrum with different moisture in 350?~?2,500 nm wavelength, to study on the relationship between soil polarized spectral data and moisture, to determine the spectral response and changes in soil moisture, and establish models between spectral data and soil moisture. We also designed a orthogonal test on the various factors that affect soil polarized spectral characteristics, in which we studied soil moisture, polarized angle, detected angle and azimuth of the various factors and their interactions. The results showed it was most significant that the soil moisture and the interaction of soil moisture and polarized angle, followed by the interaction effect of detected angle and moisture, while the polarized angle had a little impact on the soil polarized spectrum.     

嫦娥3号巡视探测器桅杆的转动角度误差检校

嫦娥3号巡视探测器桅杆的展开机构、偏航机构和俯仰机构在转动过程中存在系统性的偏差,这些误差影响了巡视探测器导航定位、地形恢复和路径规划的精度.针对这一问题,文章提出了一种间接平差模型,通过真实数据试验证明该方法能够用于对嫦娥3号巡视探测器桅杆的转动角度误差进行检校,并且具有很高的精度和稳定性.     

Mapping spiny aster infestations with QuickBird imagery

QuickBird satellite imagery acquired in June 2003 and September 2004 was evaluated for detecting the noxious weed spiny aster [Leucosyris spinosa (Benth.) Greene] on a south Texas, USA rangeland area. A subset of each of the satellite images representing a diversity of cover types was extracted and used as a study site. The satellite imagery had a spatial resolution of 2.8 m and contained 11-bit data. Unsupervised and supervised classification techniques were used to classify false colour composite (green, red, and near-infrared bands) images of the study site. Imagery acquired in June was superior to that obtained in September for distinguishing spiny aster infestations. This was attributed to differences in spiny aster phenology between the two dates. An unsupervised classification of the June image showed that spiny aster had producer's and user's accuracies of 90% and 93.1%, respectively, whereas a supervised classification of the June image had producer's and user's accuracies of 90% and 81.8%, respectively. These results indicate that high resolution satellite imagery coupled with image analysis techniques can be used successfully for detecting spiny aster infestations on rangelands.     

WebGIS中的安全防范研究

WebGIS已成为GIS发展的主流方向,在要求更大范围的数据共享和业务协作的同时,还要求更高的安全防范。分析WebGIS应用中常见的安全隐患,并从Web服务器、WebGIS应用程序和数据库服务等方面,探讨如何提高WebGIS应用系统的安全性。     

基于WINCE的开挖线放样程序设计研究

基于工程测量中参考线放样原理,通过对用全站仪放样的深入探讨和实践,以WINCE为开发平台,运用EVC工具,进行了全站仪开挖线放样程序开发。并将程序植入拓普康GTS-720全站仪中。经过阜盘高速公路路基施工实践证明,该程序大大减少了技术人员的计算量,极大地提高了开挖线的放样效率。     

一种基于约束的最短路径低频浮动车数据地图匹配算法

针对精度差、频率低的浮动车数据特点,给出了空间和拓扑约束下的最短路径浮动车数据地图匹配算法,基于不同采样频率的匹配结果证明算法准确度高。基于武汉市浮动车数据的匹配结果表明,算法具有高可靠性,可以用于浮动车数据的交通信息提取与特征挖掘。     

Optimization of land use structure based on ecological GREEN equivalent

Optimization of land use structure consists of economic and social and ecological optimization. Applying the minds of system engineering and principles of ecology, this paper presents such thoughts: the optimal forest-coverage rate calculated according to the reality of a district is set as main standard of ecological rationality in the district; through considering the value of ecosystem services of the land with GREEN equivalent (mainly cultivated land and grassland) and based on the rule, GREEN equivalent, this paper introduces the area conversion between woodland and cultivated land, also between woodland and grassland; this paper establishes a multi-dimension controlling model of optimization of land use structure. In addition, a multi-objective linear programming model for optimization of land use structure is designed. In the end, this paper tests and verifies this theory of ecological optimization, taking Qionghai city in Hainan Province as an example.