ArcGIS与AutoCAD结合在1：50000数据库更新工程中的应用

由于GIS软件平台与CAD软件平台各自具有的优势不一样,如何把ArcGIS和AutoCAD相结合,利用各自优势,快速有效地进行地形图数据库内业编辑、数据分析;本文重点讨论了GIS和CAD数据交换的问题。     

基于最小二乘配置的三维空间坐标转换

在求解未知转换参数时,鉴于公共点坐标本身的误差,提出利用最小二乘配置法进行空间坐标转换,即将公共点本身坐标作为随机参数,把转换参数作为非随机参数进行处理,最后通过实验对比分析表明,该方法明显优于一般坐标转换方法。     

基于交互多模型的水下目标跟踪方法

According to the requirements of real-time performance and reliability in underwater maneuvering target tracking as well as clarifying motion features of the underwater target, an interacting multiple model algorithm based on fuzzy logic inference （FIMM） is proposed. Maneuvering patterns of the target are represented by model sets, including the constant velocity model （CA）, the Singer mode~, and the nearly constant speed horizontal-turn model （HT） in FIMM technology. The simulation results show that compared to conventional IMM, the reliability and real-time performance of underwater target tracking can be improved by FIMM algorithm.     

Applications of Lodrigues Matrix in 3D Coordinate Transformation

Three transformation models (Bursa-Wolf, Molodensky, and WTUSM) are generally used between two data systems transformation. The linear models are used when the rotation angles are small; however, when the rotation angles get bigger, model errors will be produced. In this paper, we present a method with three main terms: ① the traditional rotation angles θ , φ ,ψ are substituted with a , b, c which are three re-spective values in the anti-symmetrical or Lodrigues matrix; ② directly and accurately calculating the formula of seven parameters in any value of rotation angles; and ③ a corresponding adjustment model is established. This method does not use the triangle function. Instead it uses addition, subtraction, multiplication and division, and the complexity of the equation is reduced, making the calculation easy and quick.     

有限带宽信道条件下的Double-delta技术多径抑制性能分析及优化设计

以一种基于码跟踪多径误差包络的多径抑制性能评估准则为基础,首先根据Double-delta技术的基本原理,首次推导出了其在无限带宽时的码跟踪多径误差公式,并由此得出了Double-delta技术的理论性能计算公式;然后以数值计算的方法分析了不同信道带宽条件下Double-delta技术的多径抑制性能。仿真结果表明,当信...     

基于资源三号卫星立体像对的DEM提取实验及其应用——以拉萨市城关区为例

利用测绘卫星立体像对提取DEM效率高、精度高。本实验的主要目的是进行资源三号测绘卫星立体像对高海拔地区DEM提取实验,比较正视、前视及后视3种视角全色影像不同组合情况的立体像对所提取DEM的效果,以拉萨市城关区为实验区,并将实验结果与SRTMDEM进行比较。实验结果显示,正视与前、后视组成的立体像对提取的DEM效果相当,均好于前视、后视全色影像组成的立体像对提取得到的DEM,拉萨市城关区空间分辨率可达10 m,效果良好,可为城市地质灾害评价等提供基础数据。     

Spatial representation in the social interaction potential metric: an analysis of scale and parameter sensitivity

The social interaction potential (SIP) metric measures urban structural constraints on social interaction opportunities of a metropolitan region based on the time geographic concept of joint accessibility. Previous implementations of the metric used an interaction surface based on census tracts and the locations of their centroids. This has been shown to be a shortcoming, as the metric strongly depends on the scale of the zoning system in the region, making it difficult to compare the SIP metric between metropolitan regions. This research explores the role of spatial representation in the SIP metric and identifies a suitable grid-based representation that allows for comparison between regions while retaining cost-effectiveness with respect to computational burden. We also report on findings from an extensive sensitivity analysis investigating the SIP metric’s input parameters such as a travel flow congestion factor and the length of the allowable time budget for social activities. The results provide new insights on the role of the modifiable areal unit problem in the computation of time geographic measures of accessibility.     

测量机器人的关键技术

本文提出了测量机器人概念,重点分析了测量机器人的组成框架及关键技术,聚焦定位与建图、场景感知、路径规划及多机协同等测量机器人前沿研究领域,综述了最新研究进展,并剖析了当前面临的技术难题,简述了测量机器人的发展机遇.     

基于规则的地理国情普查质量检查系统的设计与实现

针对全国第一次地理国情普查及四川省地理省情普查,笔者结合生产实际,研究和探讨了地理国情普查成果数据质量检查的内容、技术方法及精度指标,设计了内容完整、检查科学的质量检查模型,研发了自动化程度高、拓展性强、运行稳定、检查效率高的地理国情普查质量检查软件,介绍了软件的功能、特点及应用情况。     

基于线要素动态化简的匹配算法比较与评价

矢量线要素数据来源多样,细节层次不一,限制了已有匹配算法正确率的提高,同时也给算法评价带来困难。化简可以减少线要素细节层次,提取其主要形态,据此提出一种基于线要素动态化简的匹配算法评价新方法。对不同匹配算法采用相同数据,在相同化简算法支撑下进行匹配,从而实现对不同匹配算法的评价。首先,阐述动态化简方法提取线要素主要形态的过程;其次,利用动态化简分别辅助4种已有匹配算法,获取每个匹配算法的最优匹配正确率;最后,将4种匹配算法的原始匹配结果与加入动态化简后的匹配结果进行对比,分析化简对匹配结果的影响,并把该影响运用到匹配算法的比较和评价中来。其中,1通过匹配正确率变化、误匹配等分析了匹配算法的数据适用性;2通过化简比例系数K变化时新增匹配数量的统计,评价了匹配算法对线要素局部细节的敏感程度并提出该指标的量化方法;3结合匹配算法采用的匹配相似度指标对其作出评价。