辅助纬度反解公式的Hermite插值法新解

利用计算机代数系统,推导出了地图投影中辅助纬度与大地纬度间的正反解变换公式,发现和纠正了传统正解公式高阶项中的一些错误;借助Hermite插值法得到了符号形式的反解表达式。将各辅助纬度展开式系数表示为简单的偏心率e的幂级数形式,使得系数的表示形式更为统一。     

A bundle adjustment approach with inner constraints for the scaled orthographic projection

Bundle adjustment is a method for simultaneously calculating both the interior and exterior orientation parameters of a set of images, and the object-space coordinates of the observed points. In the case of long focal length lenses and narrow field-of-view (FOV) imaging situations, collinearity based (perspective projection) algorithms may result in linear dependencies between parameters that cause solution instability. The use of a scaled orthographic projection model based on linear algebraic formulations was therefore adopted to reduce this risk. Using quaternions, a new mathematical model is derived that includes the partial derivatives as well as the inner constraint equations for a scaled orthographic bundle adjustment. The model was then tested using two image sets of a single, small vessel (about 6 m length) with a cube target of known dimensions at two distinct ranges; perspective solutions were also calculated for comparison. RMS residual errors of 0.74-0.78 pixels associated with the new method compare favorably to a residual error range of 0.59-0.74 pixels using a perspective bundle adjustment of the same target points. Relative precisions (as a ratio of target size) of between 1:1650 and 1:750 have been achieved at ranges of 375 m and 850 m, respectively, given comparisons with the known cube dimensions. A third image dataset consisting of a network of 16 images was solved with a 1:2200 relative precision showing the new method can successfully handle high redundancy. For the experiments that were conducted, the new method was found to produce less precise results than the perspective bundle solution for a FOV of 0.50-0.65° where the object fills 5-8% of the image. However, it was found to match the precision of the perspective model (with an uncalibrated camera) for a FOV of 0.20-0.30° where the object of interest fills only 1-2% of the full image.     

高斯投影复变换与Maple计算机代数系统的实现方法

高斯投影的复变换与实变换相比具有独特的优势.使用Maple计算机代数系统,高斯投影正算及反算变换的核心就是方程求解及复积分计算.本文对高斯投影复变换进行了改进,只需建立正算变换计算式而不需要针对反算变换再建立一套变换计算式,给出了Maple系统方程求解的求根函数法以及复积分计算的积分级数分析法、椭圆积分函数法及直接积分...     

JSCORS在古城墙保护性监测中的应用与分析

本文讨论了JSCORS应用于古城墙保护性观测的基本情况,简要说明了JSCORS的一些使用方法、技巧,并讨论了在类似于古城墙的线状工程中对JSCORS所测得的数据的内业处理方法。同时,还列举了JSCORS运用于工程测量中的一些优缺点,并介绍了笔者的一些心得体会。     

对施奈德等积多面体投影的研究

提出了先确定边界、再逐步精化的研究思路,系统、直观地阐述了投影的基本原理,并推导了严密的变换公式,在此基础上给出了详细算法和部分实验结果。     

基于逐次投影寻踪的高光谱影像降维方法研究

提出了一种新的逐次投影寻踪方法,对高光谱数据进行降维处理,采用定量化的指标,通过对高光谱数据的多次一维投影,逐步选取有效成分,构建新的低维正交空间.     

济源市独立坐标与国家坐标的转换

介绍了济源市独立坐标系的建立过程,阐述了济源市独立坐标系椭球参数的计算方法,实现了独立坐标与国家坐标的转换关系.     

移动电子地图中伪3D可视化设计

定义了移动电子地图中伪3D可视化概念,提出伪3D可视化模型,并设计了快速的三维投影变换算法。进行了移动电子地图的伪3D可视化实验设计,并给出了可视化性能测试结果。     

基于Google Earth土地承包经营权工作底图的制作

对利用Google Earth影像制作农村土地承包经营权工作底图的方法和技术流程进行了全面探讨。首先在CASS 7.0软件下对集体土地所有权行政界线进行坐标转换,再使用自编程序提取界线拐点的WGS-84大地坐标,通过"地图下载器"下载Google Earth影像并拼接输出TIF影像,利用Arc Map软件的投影变换功能,将墨卡托投影的TIF影像转换为高斯投影影像,最后,在CASS 7.0软件下插入变换后的正射影像,叠加行政界线,形成完整的承包经营权外业调查工作底图。     

低空大比例尺地形图航测生产关键技术

针对传统航空摄影测量生产工艺在生产过程中遇到的影响大比例尺测图精度的问题,该文探讨了低空航测生产大比例尺地形图的关键技术。通过选用宽角相机、低航高飞行、强化影像匹配、野外布设标志控制点、优选平差模型、精化测图操作等改进方式,以提高大比例尺航测精度;组建无人飞艇低空航测系统,对提出的技术方法予以实现;最后给出了山西境内近30个县市建成区1∶500测绘生产实践的部分验证成果。