勘界测绘工作应注意的问题   总被引：1，自引：0，他引：1  

张永光  吕开云  郭德普 《华东地质学院学报》2001,24(4):327-329

介绍了勘界测绘工作的作业过程，结合勘界工作实践，指出 了勘界工作应注意的一些问题，并提出了解决这些问题的建议。  相似文献   

APPLICATION OF ORTHOGONAL EXPANSION TO MAPPING AND MODELLING     

ZHAONIAN CHENG  ERYI ZHU  NIANYI CHEN  Shanghai Institute of Metallurgy  Academia Sini  Shanghai  China 《地理学报(英文版)》1993,(4)

In this paper we discuss the orthogonal expansion of data matrices and its application to mapping andmodelling. Two new methods, modified optimal discriminant plane (MODP) for mapping and orderGram-Schmidt orthogonalization (OGSO) for modelling, are proposed and examples are given.  相似文献   

黄河中游地区环境脆弱形势   总被引：2，自引：0，他引：2  

杨勤业  刘雪华 《云南地理环境研究》1994,6(1):32-44

文章以黄河中游地区为对象，研究和分析了其环境的脆弱形势，并编制了１：２００万黄河中游地区环境脆弱形势图。将黄河中游地区的环境脆弱形势分成５类：紧张环境形势（较脆弱）、危急环境形势（脆弱）、危机环境形势（很脆弱）、灾难性环境形势及突发性灾害环境形势。区分上述不同环境形势的指标因子很广泛，结合黄河中游地区的特殊性以及环境主导因子规律，主要选择了污染、地方病、土壤侵蚀、干旱缺水，森林退化、风蚀沙化、土壤盐碱化等因子。所编制的环境脆弱形势图反映了４方面的内容：（１）不同景观类型、地理系统和区域的自然人口承载能力；（２）人类活动对自然环境造成的压力和自然环境发生不可逆变化的起因、特征和程度；（３）自然环境对人类干扰的敏感性及社会经济的弱点；（４）人类活动对自然环境影响的后果及其同自然环境、社会因素相互作用所产生的反响。在制图和分析的基础上，文章总结出了该地区脆弱环境的区域分布规律，并将环境形势、区域分布规律和主导指标因子结合起来，将黄河中游地区划分成８个区，为对整治不同脆弱形式和程度的环境提供科学依据和参考。  相似文献   

Automatic detection of a one dimensional ranging pole for robust external camera calibration in mobile mapping     

《ISPRS Journal of Photogrammetry and Remote Sensing》2013

A mobile mapping system (MMS) is the answer of the geoinformation community to the exponentially growing demand for various geospatial data with increasingly higher accuracies, captured by multiple sensors. As the mobile mapping technology is pushed to explore its use for various applications on water, rail, or road, the need emerges to have an external sensor calibration procedure that is portable, fast and easy to perform. This way, sensors can be mounted and demounted depending on the application requirements without the need for time consuming calibration procedures. A new methodology is presented to provide a high quality external calibration of cameras which is automatic, robust and fool proof. The method uses a portable, standard ranging pole which needs to be positioned on a known ground control point. While the literature focuses on solving the absolute orientation problem of the calibration, an automatic method to detect the calibration object is missing. Here, we present a mutual information based image registration technique for automatic sub-pixel localization of the ranging pole under realistic outdoor conditions. We include several robust error detection rules to allow the calibration to run without human intervention, giving as little outliers as possible, to ensure a correct calibration. Several tests are performed under various lighting and noise conditions which prove the methodology’s robustness.  相似文献   

Mapping of quick clay formations using geotechnical and geophysical methods   总被引：2，自引：1，他引：1  

K. Lundström  R. Larsson  T. Dahlin 《Landslides》2009,6(1):1-15

Quick clay has been involved in most serious, large clay slides in Sweden, Norway, and Canada. This paper describes geotechnical and geophysical methods that can be used to locate and map the extent of quick clay formations. Surface resistivity measurements and four different sounding methods have been tested. The results have been compared with sensitivities determined using fall-cone tests. The investigation shows that there is a correlation between sensitivity and electrical resistivity, which can be used to discriminate between marine clays that have been leached sufficiently to possibly form quick clay and those for which the salt content remains sufficiently high to prevent this. Although the most reliable evaluation of the variation in sensitivity was obtained by the CPT with additional measurement of total penetration force, this investigation suggests that any sounding method that uses a constant rate of advance into the ground and in which the penetration force applied on the top of the rods is measured may be used for quick clay mapping.  相似文献   

Current shortcomings of global mapping and the creation of a new geographical framework for the world     

DAVID RHIND 《The Geographical journal》2000,166(4):295-305

The vast bulk of topographic mapping - the geographical framework used to underpin many activities of the state and of business - has been created and is maintained to national standards. As a consequence, what is available differs greatly from country to country. Yet there is a range of needs for globally-consistent map information. Such needs have long been recognized: the International Map of the World was an attempt to meet them. A multiplicity of factors has constrained the National Mapping Organizations from meeting this aim. However, new technologies have enhanced our capacity to create a geographical framework almost anywhere in the world. Using such technologies, commercial and other non-commercial bodies (e.g. the US military and its counterparts within NATO) have begun to produce wide-area geographical information. This paper describes the nature of the need for global mapping, the players involved and the drivers and obstacles to progress. It proposes a rapid way to enhance the current situation through public/private sector partnerships based on a combination of skills, information assets and resources. If implemented, this could lead to global coverage of a framework derived from 1:25000 scale mapping within about two years.  相似文献   

Groundwater ecological environment and the mapping of Asia          下载免费PDF全文

DONG Hua  GE Li-qiang 《地下水科学与工程》2015,3(2):118-126

Based on the mapping of groundwater resources and environmental geology in China and its surrounding regions, Groundwater Ecological Environment Map of Asia is drawn to broadly reflect the ecological situation of Asian groundwater, categorize its ecological environment into three basic types and elaborate the research categories. This paper analyzes and summarizes the major characteristics and distribution regularities of the groundwater ecological environment of Asia to reveal the key related problem so as to provide a necessary reference for the construction and planning of One Belt and One Road.  相似文献   

Regional-typological study and mapping of geosystems: analysis of the implementation     

A.D. Abalakov  S.A. Sedykh 《Geography and Natural Resources》2010,31(4):317-323

We give an outline of the scientific-methodological principles of using the regional-typological approach in geographical research. Based on analyzing cartographic products, we demonstrate the differences in understanding and implementing the approach. The structurallogical schematic diagram for the regional-typological approach has been developed, which opens up possibilities for its implementation in the study and mapping of geosystems and can provide an integral, systemic idea of this approach.  相似文献   

电离层垂直TEC映射函数的实验观测与统计特性   总被引：2，自引：0，他引：2       下载免费PDF全文

温晋  万卫星  丁锋  乐新安  佘承莉  刘立波 《地球物理学报》2010,53(1):22-29

利用GPS信标测量获得的电离层电子浓度总含量（TEC）是沿电波路径的斜向TEC.理论研究和实际应用中,常常需要通过映射函数将斜向TEC转换为垂直方向的TEC,这在当前主要采用对电子浓度分布模型的数值积分得到模型映射函数来实现.本文在考察现有不同模型映射函数的基础上,又提出了一种源于实际观测的实验映射函数的概念与估算方法.我们利用IGS的全球GPS观测站的斜向TEC和JPL提供的垂直TEC数据获得了2006年期间的实验映射函数,并对所得结果进行了初步统计分析.在卫星天顶角较小时,上述实验映射函数和模型映射函数之间相差甚微,均可很好描述垂直TEC与斜TEC之间关系;但卫星天顶角较大时,实验映射函数和常用的模型映射函数之间存在明显差异.本文认为,这种差异主要是因为现有模型映射函数中没有考虑到等离子体层的贡献.我们认为采用基于实验映射函数的模式,或者通过考虑等离子体层的贡献对现有模型映射函数进行改进,可以有效提高电离层TEC的估算精度.  相似文献   

Three-dimensional mapping of a landslide using a multi-geophysical approach: the Quesnel Forks landslide   总被引：7，自引：3，他引：4  

A.?BichlerEmail author  P.?Bobrowsky  M.?Best  M.?Douma  J.?Hunter  T.?Calvert  R.?Burns 《Landslides》2004,1(1):29-40

A landslide located on the Quesnel River in British Columbia, Canada is used as a case study to demonstrate the utility of a multi-geophysical approach to subsurface mapping of unstable slopes. Ground penetrating radar (GPR), direct current (DC) resistivity and seismic reflection and refraction surveys were conducted over the landslide and adjacent terrain. Geophysical data were interpreted based on stratigraphic and geomorphologic observations, including the use of digital terrain models (DTMs), and then integrated into a 3-dimensional model. GPR surveys yielded high-resolution data that were correlated with stratigraphic units to a maximum depth of 25 m. DC electrical resistivity offered limited data on specific units but was effective for resolving stratigraphic relationships between units to a maximum depth of 40 m. Seismic surveys were primarily used to obtain unit boundaries up to a depth of >80 m. Surfaces of rupture and separation were successfully identified by GPR and DC electrical resistivity techniques.  相似文献