Distributed allocation and dynamic reassignment of channels in UAV networks for wireless coverage

Providing wireless coverage to users using Unmanned Aerial Vehicles (UAVs) encounters two major challenges: deployment and channel allocation. To this end, solutions to both issues are proposed in this paper. An overloaded UAV attempts to acquire more channels by performing channel bonding/aggregation followed by requesting its chosen peers to move closer for load sharing. The proposed channel reallocation schemes minimize interference caused by channel reassignments, or change in network topology. The simulation results show that when employing these schemes, more data is served with reduced discontinuous service time and efficient usage of limited battery power.     

焊缝表面缺陷激光扫描三维重构测量

为检测工件焊缝表面缺陷，采用点激光位移传感测距法和数据拟合技术进行焊缝表面缺陷检测试验研究. 首先采集缺陷表面轮廓数据点，利用高斯滤波对原始数据降噪处理. 再对处理后的数据点进行Delaunay三角剖分，使散乱点连接并结合其空间坐标重构出缺陷的三维模型. 结果表明，基于点激光位移传感测距技术及焊缝表面缺陷三维重构方法可以准确判断焊缝成形情况.     

Density estimates on the unit simplex and calculation of the mode of a sample

This paper addresses reliable and efficient calculation of the mode of a multivariate sample, which is a classical fusion function. In particular, we focus on the inputs given on the unit simplex, when aggregating elements of Atanassov intuitionistic fuzzy sets, interval-valued fuzzy sets and their extensions, as well as compositional data. We outline the use of a specially designed 2-additive fuzzy measures and the Choquet integral for the purposes of reducing computational complexity in higher dimensions. We present computational analysis and benchmark four different methods of density-based mode estimation.     

利用全站仪三角高程建立井下首级高程控制

通过分析全站仪三角高程的精度,论述了用全站仪三角高程代替井下水准测量建立首级高程控制的可行性。可利用全站仪施测矿井井下基本控制导线,一并建立井下首级高程控制,以永久导线点兼作高程控制点。     

基于约束Delaunay三角划分法在节理图上实现网格自动剖分

分析了现有的在节理图上自动生成有限元网格方法的不足之处，提出了应用约束Delaunay三角划分法来实现网格剖分。该方法将所有的节理线看作特征约束线，在散乱点约束的Delaunay三角划分的基础上，逐次嵌入约束线，然后再应用细化算法进行网格加密，得到符合数值计算精度要求的网格。     

无人机航摄系统在农村土地承包经营权确权登记中的应用探讨

文中结合农村土地承包经营权确权登记工作,介绍了无人机航摄系统获取数据和数据后处理技术流程,阐述了其成果在该项目中的应用。通过1∶2 000正射影像底图的生产,对关键的技术流程进行了探讨。     

基于数字高程模型的输电线路虚拟地形绘制优化算法

针对现有输电线路仿真培训系统复杂地形和大规模场景的建模问题,研究了基于数字高程模型(DEM)的虚拟地形绘制优化算法.通过采集输电线路走廊位置和范围内的地形高程数据,结合分治算法和流水线技术实现Delaunay三角网的并行构建.并针对高斯曲面方程拟合三角形表面中的参数问题,提出了基于遗传算法的最优参数选择方法,降低了地形表面的整体误差.在Qt平台上实现了输电线路真实场景的三维可视化重构.仿真结果表明,本算法有效实现了输电线路真实地形的虚拟可视化,提高了虚拟场景的还原度和沉浸感.     

pH值对废水中氨氮监测结果的影响

简要地介绍了像素工厂,探讨了在像素工厂中对无人机遥感影像进行空三测量方法。实现了像素工厂无人机空三成果与传统数字摄影测量工作站的无缝衔接,并对采集的要素进行实地精度检测分析,形成了利用无人机遥感影像进行3D产品生产的作业体系。     

Enhancing multisensor data fusion on light sectioning coordinate measuring systems for the in-process inspection of freeform shaped parts

A method for automatic determination of sensors positions and orientations in multisensor laser triangulation coordinate measuring systems is presented. Based on a series of measurements on a conical artifact without the use of external light sources, the approach allows for both optimized adjustment of the physical sensors alignment and improved 3D data registration by software. Simulations were conducted to quantify the sensitivity of the method. Experimental results based on measurements of steep details of complex shaped parts show a 5-times reduction of deviations between measurements of sensors with respect to an already optimized adjustment by manual methods.     

基于C#和AutoCAD的Delaunay三角剖分算法的实现

本文是在.net平台下AutoCAD二次开发方面的文章,是对Delaunay三角剖分算法的总结。在算法的编程实现过程中,作者提出了许多新颖的设想,并最终获得了正确的计算结果和理想的时间效率。针对算法实现的整体框架和步骤,几个算法关键点以及算法的时间复杂度方面,文中提供了比较详细的论述。