江苏省国土资源基础数据整合技术研究与实践

本文结合《江苏省国土资源基础数据库建设试点》项目,开展国土资源基础数据库整合关键技术的研究。文中介绍了整合技术的总体思路和数据整合关键技术研究成果,以及成果应用效果,为国土资源行业开展类似工作提供一些实践经验参考。     

GPS道路修测系统在中国公路网测绘工程中的应用

本文介绍了车载式GPS道路修测系统的基本原理和体系结构，详细讲述了该系统在“中国公路网GPS测绘工程”的应用。“中国公路网GPS测绘工程”是由多家部门共同参与的大型道路测绘项目，目的是解决现有公路网数据库现势性差的问题。文中结合“中国公路网GPS测绘工程”重点阐述了修测系统中几个关键技术的实现方法，最后给出了修测系统在该工程中的使用效果。     

上海市集中测绘成果管理系统的建设与维护

本文在深入调研上海市集中测绘成果管理系统的基础上,通过对系统的建立与长期维护的总结,简要的介绍了系统实现的功能与系统架构,总结了系统建设过程中的思路与做法。着重阐述了系统在整合测绘处理与成果管理、保持基础数据的现势性方面所取得的成果,总结了系统在建设与使用过程中的优缺点,为其它地区建立或改造测绘成果系统提供借鉴。     

一定分布模式下的最优Lp估计

观测数据在一定的分布模式下,需从理论上解决究竟用多大的ｐ值进行Ｌｐ估计（最优ｐ值的确定）,本文基于渐近方差整体最小的原则,给出了最优Ｌｐ估计的定义。观测数据中含有粗差（异常值）的扰动,其误差分布可视为污染分布,作者分析了最优ｐ值的大小,结果表明,若观测数据中含有不同大小、数量的粗差,为使Ｌｐ估计差最小,则ｐ将取［１．２,１．５］中的某一定值,Ｌｐ估计结果最优,此结论对测量数据处理具有一定的参考价值     

同步设计和异步设计的最优性

针对Grafarend的四类设计,提出了网的同步设计,论证了异步设计的相互关系,并从最优性及解集论证了同步设计和异步设计的最优性问题.得到整体最优和局部最优。最后以一算例表明结果的合理性。     

测量极值问题的经验解式--兼论绝对和极小问题

测量上有许多极值问题,如各种准则下的平差,权的最优分配,网的优化方案等,多可归于线性极值问题,且多不适用寻常数学解法。但同型问题往往已经作过多次解算。因此本文以单纯形法为主,强调利用已有经验,直接逼近优解,或经少数次迭进达到优解,然后极值条件加以验证。为此文中着重提出通用解式及优解条件,期能得出优解公式,有相当的适用范围。     

贵州煤田地质局技术队伍建设问题探讨

目前地质市场由计划经济转化为市场经济,市场的竞争究其本质是人才竞争。因此应该采取科学合理的技术人才资源管理方法和管理体制,以整体和局部、近期和长远为目标进行有计划、有步骤的技术队伍建设,注重从才培养,激励地质技术人员专业技能的提高,采用倾斜政策留住人才、招纳人才,只有这样贵州煤田地质局才能在不久的将来拥有一支精干、高效的地质专业技术队伍,确保全局乃至二级单位适应煤田地质市场的需要,保证全局科学、和谐健康有序的发展。     

An enhanced approach for surface flow routing over drainage‐constrained triangulated irregular networks

The accuracy and efficiency of the simulations in distributed hydrological models must depend on the proper estimation of flow directions and paths. Numerous studies have been carried out to delineate the drainage patterns based on gridded digital elevation models (DEMs). The triangulated irregular network (TIN) has been increasingly applied in hydrological applications due to the advantages of high storage efficiency and multi‐scale adaptive performance. Much of the previous literature focuses mainly on filling the depressions on gridded DEMs rather than treating the special cases in TIN structures, which has hampered its applications to hydrological models. This study proposes a triangulation‐based solution for the removal of flat areas and pits to enhance the simulation of flow routing on triangulated facet networks. Based on the drainage‐constrained TIN generated from only a gridded DEM by the compound point extraction (CPE) method, the inconsistent situations including flat triangles, V‐shape flat edges and sink nodes are respectively identified and rectified. The optimization algorithm is an iterative process of TIN reconstruction, in which the flat areas are generalized into their center points and the pits are rectified by embedding break lines. To verify the proposed algorithm and investigate the potential for flow routing, flow paths of steepest descent are derived by the vector‐based tracking algorithm based on the optimized TIN. A case study of TIN optimization and flow path tracking was performed on a real‐world DEM. The outcomes indicate that the proposed approach can effectively solve the problem of inconsistencies without a significant loss in accuracy of the terrain model.     

Extraction of Alteration Mineral Information from Moderate Remote Sensing Images Using MPS Method

Although alteration minerals related to metallogenesis is very important in mineral exploration, information of alteration mineral is weakly expressed in remote sensing imagery, which is often subject to interfering noise and sometimes limited in spectral and spatial resolutions. Because of easy access, moderate images are the main sources of alteration mineral information. Therefore, it is very important to develop alteration mineral information extraction methods from remote sensing images. In this paper, a combined method based on Mask, principal component analysis (PCA) and support vector machine method (SVM) was used to extract alteration mineral information from Enhanced thematic mapper plus remote sensing data with limited spectral and spatial resolutions. First, a mask image of the remote sensing imagery was created to remove interference information such as vegetation, shadow and water. Then, PCA was employed to collect sample data relating to iron, argillic, and carbonatization alteration. Finally, SVM was used to deal with alteration anomaly and build a feature extraction model of high accuracy. The Mask-PCA-SVM model is used to extract alteration mineral information from remote sensing images of Hatu area, Xinjiang Uygur Autonomous Regions, China. The results show that the new methods proposed in this paper can coincide well with known deposits occurrences, rate reached 86.51%. While, the consistent rate with known deposits of the ratio model, PCA model and Spectral angle mapper model were only 3.37, 65.08 and 69.05% respectively. This suggests that the proposed model can find the actual distribution of mineral deposits more effectively by reducing interference to a greater degree.