Establishment and data processing of high-precision city subsidence monitoring network by GPS surveying instead of leveling

The feasibility of monitoring the change of city settlement using GPS surveying instead of leveling is studied. A fiducial network and a monitoring network are established in Ningbo city. Two periods of GPS observation are completed. Some measures are taken during the observation in order to ensure to obtain the high-precise height component. The Saastamoinen model is adopted in the data processing of the dry component part of the tropospheric delay. The wet component change of the tropospheric delay is estimated by stochastic processes model. When Bernese software is used to process the data, the millimeter level precision of height measuring is achieved.     

一个非线性最小二乘混合算法及其在多源多维多类型测量数据联合非线性处理中的应用

建立了一个多源、多类型观测量联合处理的数学模型,针对该模型,结合非线性最小二乘的两种常用算法———修正的高斯—牛顿法与阻尼最小二乘法,建立了一个非线性最小二乘的混合算法,该算法不仅具有全局收敛性,而且在一定条件下局部二次收敛。通过算例验证了算法的有效性。     

数码城市中建筑物三维CAFM研究

提出了一种室内空间的楼层房间结构多边形剖分方法，讨论了数码城市中室内三维CAFM的数据管理、基本功能的实现和可见性算法。     

模糊直方图及其在测量数据处理中的应用

从分析绘制异常型直方图的观测误差出发，讨论了直方图区间的模糊化问题，给出了计算模糊频数的公式和绘制模糊直方图的方法，并结合实例，说明了模糊直方图的优越性。     

图像处理技术在印章识别预处理中的应用

阐述了印章识别系统的预处理过程，包括图像的去噪、去背景、二值化、边缘提取等几个部分，其中的去背景部分采用了利用颜色信息提取印章的方法，并对其因污染而残缺的部分进行了修复。试验表明，该预处理过程处理实际图像可以达到比较理想的效果。     

增强电子地图表现力的几个方面

电子地图是一种新兴的地图产品，正服务于社会的各行各业，提高电子地图的表现力，加大电子地图的服务力度，是人们对它的客观要求。但是，电子地图的设计坂理和方法还远远没有解决，电子地图的制作还没有统一的规范和标准。本文从图形界面、表现内容、功能接口等各方面，对加强电子地图表现力和改善它的制作方法进行了研究，这些具体的措施和方法在笔者制作的各种电子地图中得到了体现，反映很好。     

空间信息栅格SIG框架体系与关键技术研究

空间信息数据量大、处理复杂、难以共享的问题对其研究和应用提出了挑战。空间信息栅格(Spatial Information Grid，SIG)作为创新性的网络空间信息基础设施和技术体系，集成并拓展信息栅格、空间信息系统、Web服务等前沿技术，以“服务”为中心，实现一体化智能化的空间信息获取、存储、组织、分发、分析处理、应用、融合以及互操作，形成基于网络的空间信息资源共享与集成。在给出SIG基本定义的基础上，明确了SIG技术要素和特征，探索并构建了开放性的SIG框架体系，重点研究了SIG中的空间数据共享和分析处理服务技术，为SIG相关研究的拓展和深入提供了总体框架和技术基础。     

Object Extraction Based on Evolutionary Morphological Processing

This paper introduces a novel technique for object detection using genetic algorithms and morphological processing. The method employs a kind of object oriented structure element, which is derived by genetic algorithms. The population of morphological filters is iteratively evaluated according to a statistical performance index corresponding to object extraction ability, and evolves into an optimal structuring element using the evolution principles of genetic search. Experimental results of road extraction from high resolution satellite images are presented to illustrate the merit and feasibility of the proposed method.     

华南暴雨试验天气雷达数据处理及暴雨中尺度结构个例分析

文中描述了华南暴雨试验多普勒天气雷达数据的处理方法，建立了一套集图像显示、数据预处理及风场反演分析为一体的多普勒天气雷达的分析应用系统。该系统生成了三维正方形网格和经纬度网格的回波强度值，以及经噪声控制和速度扩展的径向速度风场，提交了华南暴雨试验雷达数据库。该文以1998年6月9日08:00(北京时) 探测数据为例，给出了华南暴雨试验区内4部多普勒天气雷达的反演雨强图和两部雷达的风场反演拼图，并进行了暴雨中尺度风场结构的初步分析。     

Structural fabric of the Central Metasedimentary Belt of southern Ontario, Canada, from deep seismic profiling

The Central Metasedimentary Belt boundary tectonic zone (CMBbtz) is a 10–20-km-wide zone of intense structural deformation within the 1.3–1.0 Ga Grenville orogen of southeastern Canada. The crustal structure of the exposed CMBbtz has been well studied, but its sub-Phanerozoic location and geometry beneath the urban development and nuclear stations of the Toronto region are not well known. A new 75-km Lithoprobe reflection profile acquired close to Toronto provides a clear image of the CMBbtz as a panel of southeast-dipping reflections that extends with moderate dip (<25°) to mid-crustal depth (25 km). These dipping reflections truncate and (or) overprint a subhorizontal band of reflectivity at 21 km depth. The seismic line is oblique to the major structural trends; cross-dip analysis shows that the southeast-dipping reflections have a strike and dip of N13°E and 25°, whereas the “subhorizontal” reflections strike and dip at N65°E and 20°, respectively. Both of these bands of reflectivity can be correlated to magnetic anomalies in the CMBbtz or its immediate footwall. Magnetic anomalies with similar strike directions are well expressed within a distinct rhomboid-shaped region (106×109 km) in the subsurface of western Lake Ontario, herein named Mississauga domain. Taken together, the seismic and magnetic data are inconsistent with existing models, in which the CMBbtz is extrapolated beneath Lake Ontario along a linear magnetic anomaly. We propose a revised subsurface trace of the CMBbtz along the western edge of the Mississauga domain. Small earthquakes in western Lake Ontario appear to cluster along trends co-linear with ENE magnetic anomalies, suggesting a possible degree of basement tectonic control on local intraplate seismicity.