川藏公路中段地质灾害现象的航空遥感研究

川藏公路巴塘至林芝段位于我国青藏高原东南部,该地区是现今地壳运动十分强烈的地区之一,地形起伏强烈,气候变化多样,因此地质灾害十分发育,川藏公路就穿过这样一个复杂的地区。为查明公路沿线的地质灾害分布情况,90年代初,地矿部航空物探遥感中心沿川藏公路进行了彩色红外航空摄影,比例尺为1∶6万。通过彩色红外航片的解译及野外实地观测,圈定出滑坡、泥石流及崩塌等灾害现象,并对这些灾害的强度、活动性及其对公路的影响进行分析,最后对灾害成因及治理方法提出了建议。     

高分辨率卫星影像立体测图分析研究

运用高分辨率卫星遥感影像立体像对,利用少量的外业控制点,进行l：10000比例尺地形图立体测图精度试验,获取分辨率更高的彩色影像。     

基于GIS和物联网的特种行业管理信息系统的设计与实现

针对我国特种行业的管理现状,提出一种结合GIS和物联网的特种行业管理信息系统的概念,阐述该系统的体系架构、主要功能模块及系统所涉及的三网融合、室内三维建模、智能GIS分析等关键技术,并重点介绍GIS技术和物联网技术在特种行业自动化、网络化、数字化管理方面的重要应用。     

电子签章技术在办公自动化系统中的应用

电子签章技术是应用十分广泛的一种信息安全技术,其用来保证信息在传输过程中的真实性、完整性以及不可否认性。本文分析了办公自动化系统中存在的安全问题,在此基础上阐述了电子签章的概念、分类、实现原理以及其在办公自动化系统中应用的可行性和原则,并对系统的总体框架和功能进行了详细描述。     

基于最佳用途的土地用途有偿管制机制探索

当前基于现状用途的管制存在管制方式偏行政化、管制手段无偿化导致农村集体土地收益偏向国有、非农产业和城市分配,重塑用途管制制度已显示出迫切性。本文探索基于最佳用途,通过"用途差"和"用途差"交易实现土地用途有偿管制的机制,认为通过用途有偿管制机制不仅可以保护农用地,特别是耕地资源,保障土地资源的可持续利用。而且,可激活土地资源价值,特别是有助于农用地资源资产、资本化,缩小农村、农业和农民家庭资产与收入与城镇的差距。     

The determination of potential difference by the joint application of measured and synthetical gravity data: a case study in Hungary

In an elementary approach every geometrical height difference between the staff points of a levelling line should have a corresponding average g value for the determination of potential difference in the Earth’s gravity field. In practice this condition requires as many gravity data as the number of staff points if linear variation of g is assumed between them. Because of the expensive fieldwork, the necessary data should be supplied from different sources. This study proposes an alternative solution, which is proved at a test bed located in the Mecsek Mountains, Southwest Hungary, where a detailed gravity survey, as dense as the staff point density (~1 point/34 m), is available along a 4.3-km-long levelling line. In the first part of the paper the effect of point density of gravity data on the accuracy of potential difference is investigated. The average g value is simply derived from two neighbouring g measurements along the levelling line, which are incrementally decimated in the consecutive turns of processing. The results show that the error of the potential difference between the endpoints of the line exceeds 0.1 mm in terms of length unit if the sampling distance is greater than 2 km. Thereafter, a suitable method for the densification of the decimated g measurements is provided. It is based on forward gravity modelling utilising a high-resolution digital terrain model, the normal gravity and the complete Bouguer anomalies. The test shows that the error is only in the order of 10⁻³mm even if the sampling distance of g measurements is 4 km. As a component of the error sources of levelling, the ambiguity of the levelled height difference which is the Euclidean distance between the inclined equipotential surfaces is also investigated. Although its effect accumulated along the test line is almost zero, it reaches 0.15 mm in a 1-km-long intermediate section of the line.     

Using gravity and topography-implied anomalies to assess data requirements for precise geoid computation

Many regions around the world require improved gravimetric data bases to support very accurate geoid modeling for the modernization of height systems using GPS. We present a simple yet effective method to assess gravity data requirements, particularly the necessary resolution, for a desired precision in geoid computation. The approach is based on simulating high-resolution gravimetry using a topography-correlated model that is adjusted to be consistent with an existing network of gravity data. Analysis of these adjusted, simulated data through Stokes’s integral indicates where existing gravity data must be supplemented by new surveys in order to achieve an acceptable level of omission error in the geoid undulation. The simulated model can equally be used to analyze commission error, as well as model error and data inconsistencies to a limited extent. The proposed method is applied to South Korea and shows clearly where existing gravity data are too scarce for precise geoid computation.     

A hierarchical model for estimating methane emission from wetlands using MODIS data and ARIMA modeling

A three-step hierarchical Semi Automated Empirical Methane Emission Model (SEMEM) has been used to estimate methane emission from wetlands and waterlogged areas in India using Moderate Resolution Imagine Spectroradiometer (MODIS) sensor data onboard Terra satellite. Wetland Surface Temperature (WST), methane emission fluxes and wetland extent have been incorporated as parameters in order to model the methane emission. Analysis of monthly MODIS data covering the whole of India from November 2004 to April 2006 was carried out and monthly methane emissions have been estimated. Interpolation techniques were adopted to fill the data gaps due to cloudy conditions during the monsoon period. AutoRegressive Integrated Moving Average (ARIMA) model has been fitted to estimate the emitted methane for the months of May 2006 to August 2006 using SPSS software.     

对城市类电子地图中提供优化公交乘车方案的分析及其算法思路

介绍了当前电子地图中查询公交车方案功能的现状,并从普通计算机用户的实际情况出发,提出了优化乘车发案算法思路。     

测绘与你同行

测绘,字面上的含义似乎就是测量和绘图,英文即Ｓｕｒｖｅｇｉｎｇａｎｄ Ｍａｐｐｉｎｇ,然而,在科学技术飞速发展的今天,当Ｇｅｏｍａｔｉｃｓ或Ｇｅｏｉｎｆｏｒｍａｔｉｃｓ已被广泛接受和认同并取代传统测绘的概念时,可以用地理信息产业、地球空间信息学或地相学、地理信息学等来翻译或诠释,它所涵盖的就是我们今天所关注的现代测绘。 山高水远,日迁月换,星移斗转,沧海桑田,经天纬地,九州方圆……,都要用测绘特有的手段、风格与魅力来展现,测绘正以前所未有的影响力和渗透力淋漓尽致地施展着她不可替代、不可或缺的独到优…