关于图解(航测)法在浙江省土地确权中精度影响因素的探讨

开展土地确权登记是贯彻党的"十八大"精神,开展不动产登记的重要内容,是中央的重大决策部署。农业部经过多年试点颁发了土地确权标准,是基于全国统盘考虑的。浙江省人多地少,且地块面积小,大多数分布在丘陵山区地带,通过图解法能否满足土地土地确权标准要求,笔者通过对某地区的试验,得出结论与体会,以飨读者。     

关于GPS高程测量精度的分析比较

近年来,GPS技术得到了广泛的应用,但是科学数据表明,GPS高程测量精度还受到一些因素的影响,因此,限制了GPS测量功能的发挥。为了使GPS高程测量在实际中得到更加广泛的应用,本文对GPS高程测量的基本原理和影响因素进行了分析,经过比较,重点研究如何提高GPS高程测量精度。     

三维激光扫描技术在文物建筑建档保护工作中的应用探讨

利用三维激光扫描技术能够获得真实、准确、详尽的可视化成果,对于文物建筑建档保护工作迈向数字化、信息化具有重要意义,已成为文物建档保护的前沿技术手段。本文结合实际案例归纳了文物建筑扫描的外业注意事项,阐述了内业处理时点云拼接、点云质量检查以及数据管理和存储的方法,探讨了扫描点云总体拼接精度的评价方法,并对扫描数据成果的应用进行了挖掘延伸。     

港珠澳大桥拱北隧道静力水准自动化监测系统应用研究

静力水准自动化监测系统具有精度高、自动化性能好、可实时监测等特点,在自动化监测领域得到广泛的应用。本文结合港珠澳大桥拱北隧道静力水准自动化监测项目的应用实践,对静力水准自动化监测系统的测量原理、现场安装方法、系统调试、数据采集与分析及监测精度等方面进行了论述。从工程的完成情况及数据反映来看,静力水准自动化监测系统的应用取得了较好的成果,可以较稳定地替代人工进行施工期内的隧道监测。     

国产卫星遥感数据在电力选线中的适用性研究

国产卫星遥感数据以其大范围同步观测、综合成本较低等特点在电力选线中具有潜在的应用优势。本文以某220 k V架空输电线路设计为例,对高分二号正射影像进行无控定位精度和有控定位精度分析比较,以及对资源三号影像进行区域网平差,统计分析其在无控制点和有控制点情况下的平差精度。研究表明:高分二号卫星影像在有控制点的情况下其纠正精度完全能够满足1∶10 000全地形比例尺精度要求,利用资源三号影像制作DSM的高程精度能够满足山区1∶10 000地图比例尺要求。综合电力选线相关规程中对选线各阶段的比例尺要求,国产高分二号和资源三号联合应用,完全能够满足山地地区的电力选线的可研性和初设阶段的平面及高程精度需求。     

Introducing landscape accuracy metric for spatial performance evaluation of land use/land cover change models

Performance evaluation is a critical step for land use/land cover (LULC) change modelling. It can be conducted through pixel quantity and its geographical location according to majority of current approaches. It is hence important to know to what extent spatial patterns of a given landscape are properly replicated in simulated LULC maps. Therefore, a new validation metric, named as landscape accuracy metric (LAM), is introduced by inspiration from landscape ecology. Unlike pixel quantity validation metrics, model performance is measured by LAM through quantifying spatial patterns including structure, composition and configuration attributes. The functionality of LAM was studied to assess the performance of the built-up change simulation under historical, ecological and stochastic scenarios, applying Cellular Automata Markov model. LAM is a flexible measure such that modellers can apply this metric through adding or eliminating various metrics of their interest in a selective manner and under different environmental circumstances.     

气象要素插值的空间化精度提高方法研究

为了提高气象要素空间化的精度,本文提出通过预先对气象数据进行处理,然后再进行空间化,以比较直接插值与原始数据处理之后再插值的精度的变化。文中采用数据为全国743个常规气象站40 a(1961—2000年)整编气象资料及2005年的常规气象资料;插值方法有反距离加权法(IDW)、克立格法(Kriging)和样条函数法(Spline);数据预处理方法采用距平处理。结果发现:使用IDW、Kriging和spline对平均温度距平进行插值精度比较,发现IDW方法最优;温度距平精度的提高比降水和相对湿度要好;降水距平误差呈现由东向西递增的趋势。由此可见,对气象要素做距平处理可以有效提高插值精度。     

Estimation of the accuracy of geopotential models

Summary The new Geopotential Model Testing (GMT) method has been theoretically developed and practically applied. It is free of any hypothesis, the limiting factors are the accuracy of the geocentric position of the GMT sites and of their normal heights, as well as the accuracy of the geopotential value W₀ on the geoid used as the testing value given a-priori. The GMT procedure occurs on the physical Earth's surface, no reductions are applied. No limits as regards the magnitude of the heights above sea level of the GMT sites are required. The rms error at discrete points of the most recent geopotential model JGM-3 comes out at about ± 1·5 m.     

Seafloor Habitat Mapping on the Oregon Continental Margin: A Spatially Nested GIS Approach to Mapping Scale, Mapping Methods, and Accuracy Quantification

We implement a geographic information system (GIS) to map surficial geologic habitats (SGH) with varying scales at Nehalem Bank, Oregon, USA. Geologic interpretation was first used to produce a regional-scale SGH map of mega habitats. Local-scale algorithmic classification techniques were then implemented where data density and richness permitted the mapping of meso (10 m-1 km) macro scale (1-10 m) habitat features. We use a ranked-(data) density approach to assess the distribution and quality of input data for the regional SGH map. We then apply a virtual reference dataset and error matrix technique to assess the thematic accuracy of local-scale maps.     

电感耦合等离子体发射光谱法测定石膏矿样品中的三氧化硫

样品用稀盐酸处理,在酸性条件下石膏样品中的三氧化硫以硫酸根状态存在于待测溶液中,过滤除去酸不溶物。处理好的待测溶液可直接上等离子体发射光谱仪ICAP-6300(美国热电制造)上测定。方法的检出限为0.01%,采用本法测定国家标准物质GBW03109,GBW03109a,GBW03110,GBW03111a,结果表明标准样品测定的相对误差为-0.411%~0.274%,相对误差允许限为1.07%,能够满足分析质量要求。