月球线性构造分类体系研究

月球线性构造是月球科学研究中的重要组成部分,建立月球线性构造分类体系是月球地质图编研的关键。前人对月球线性构造的分类研究主要基于月表的形貌特征,划分的线性构造类型参差不齐,尚未形成一个公认的、规范的、具有普适性的线性构造分类体系,以至于分类结果的可对比性差、参考性和易操作性较低,不利于月球线性构造纲要图的编制。并且月球线性构造的概念混乱、术语不统一,存在"同物异名、同词异义、异词同义、涵义不明"的现象,不利于全球性的统一制图和成果的展示及使用。鉴于此,本文采用多指标组合的分类方法,以成因机制和形貌特征作为主要指标,兼顾物质组成,再结合线性构造形成的动力学机制,建立了符合月球动力学演化背景的、统一规范的线性构造类型划分的新方案,避免了单以形貌特征为依据来分类出现的混乱状态,具有较好的科学性和可操作性。将月球的线性构造类型划分为:内动力地质作用形成的线性构造,包括皱脊、月溪、地堑、断裂;外动力地质作用形成的线性构造,包括坑缘断裂和坑底断裂,以及多成因机制、多动力来源作用形成的特殊类型如坑链等。在此基础上,并利用多源遥感数据建立了易于判别且具有代表性的线性构造识别标志,可为全月球线性构造的统一制图提供识别依据。     

基于Google API的地震信息地图发布系统

Google Map及相关工具功能强大,是可二次开发的地理信息平台。介绍运用Google MapAPI技术,实现动态实时更新的地震信息发布系统,并简单应用。     

多接口地图符号库的设计与实现

本文简要介绍了信息时代地图产品的主要表现形式,并针对地图出版软件系统存在的不足,论述了多接口地图符号库设计和应用的必要性。在分析相关技术的基础上,提出了一种地图符号库多接口的架构方式,实现了针对地图不同输出目标,使用同一套地图符号库,输出GDI、EPS、PDF和SVG等不同文档格式的方法。     

A Review of: “Applications of Spatial Data Structures: Computer Graphics,Image Processing,and GIS”. By H. SAMET. (Addison-Wesley Publishing Company,Inc, 1989.) [Pp. xv + 507; figures,tables, appendix,references, name and credit index,subject index.] Price US $49.95. ISBN 020150300 X (hardback).

The introduction of automated generalisation procedures in map production systems requires that generalisation systems are capable of processing large amounts of map data in acceptable time and that cartographic quality is similar to traditional map products. With respect to these requirements, we examine two complementary approaches that should improve generalisation systems currently in use by national topographic mapping agencies. Our focus is particularly on self‐evaluating systems, taking as an example those systems that build on the multi‐agent paradigm. The first approach aims to improve the cartographic quality by utilising cartographic expert knowledge relating to spatial context. More specifically, we introduce expert rules for the selection of generalisation operations based on a classification of buildings into five urban structure types, including inner city, urban, suburban, rural, and industrial and commercial areas. The second approach aims to utilise machine learning techniques to extract heuristics that allow us to reduce the search space and hence the time in which a good cartographical solution is reached. Both approaches are tested individually and in combination for the generalisation of buildings from map scale 1:5000 to the target map scale of 1:25 000. Our experiments show improvements in terms of efficiency and effectiveness. We provide evidence that both approaches complement each other and that a combination of expert and machine learnt rules give better results than the individual approaches. Both approaches are sufficiently general to be applicable to other forms of self‐evaluating, constraint‐based systems than multi‐agent systems, and to other feature classes than buildings. Problems have been identified resulting from difficulties to formalise cartographic quality by means of constraints for the control of the generalisation process.     

Wavelet triangulated irregular networks

GIS applications have recently begun to emerge on the Internet. The management of three-dimensional geographic datasets in this distributed environment poses a particularly challenging problem, which highlights the need for a good data representation. This paper presents a new multiresolution data representation: the Wavelet Triangulated Irregular Network (WTIN). Compared to the traditional cell-based Digital Elevation Model (DEM) format and the Triangulated Irregular Network (TIN) format, it is more compact and suitable for scalable distributed GIS services. This format is based on the second-generation wavelet theory and is specially designed for geographical height field data. The modified Butterfly scheme is used for constructing the wavelet transform. For every point in the geographic surface, only a single wavelet coefficient is used, which makes the final data representation very efficient and easy to compress. Because the transform used in the data representation is a linear filter operation, the computational efficiency is better than other multiresolution data formats for terrain surfaces. Results from numerical experiments on real data are given to demonstrate that the proposed data representation can be efficiently implemented. The results show that the proposed WTIN data format can provide multiresolution data sets, which achieve significant compression while preserving geographical features. The quality is found to be quite acceptable for geographical terrain representation.     

Further developments of a fuzzy set map comparison approach

Fuzzy set map comparison offers a novel approach to map comparison.The approach is specifically aimed at categorical raster maps and applies fuzzy set techniques, accounting for fuzziness of location and fuzziness of category, to create a similarity map as well as an overall similarity statistic: the Fuzzy Kappa. To date, the calculation of the Fuzzy Kappa (or K-fuzzy) has not been formally derived, and the documented procedure was only valid for cases without fuzziness of category. Furthermore, it required an infinitely large, edgeless map. This paper presents the full derivation of the Fuzzy Kappa; the method is now valid for comparisons considering fuzziness of both location and category and does not require further assumptions. This theoretical completion opens opportunities for use of the technique that surpass the original intentions. In particular, the categorical similarity matrix can be applied to highlight or disregard differences pertaining to selected categories or groups of categories and to distinguish between differences due to omission and commission.     

基于GIS的矿产资源专题图制作

结合编制矿产资源专题图,探讨了基于GIS的矿产专题地图的设计流程以及制作方法 ;针对ArcGIS自带符号库不能满足专业需要的现状,重点研究了矿产资源类型符号库的设计与实现方法,并通过绘制徐州市矿产资源分布图进行了验证。     

一种基于Google Map API的渔港地图调用方式研究

对谷歌地图API技术的原理、实现方法以及目前在各个行业应用情况进行研究,提出服务渔港的谷歌地图API调用的建议与方法。通过谷歌地图为开发者提供的地图API,将谷歌卫星地图嵌入或调用到已开发的地理信息平台中,使渔港的展示效果更为真实,同时也为后续面向渔港建设的地图产品开发做好知识储备。     

The Military Map of the United Kingdom and its Impact on Mapping in the Twentieth Century

Abstract

Considerable attention has been paid in the literature to the changing style of Ordnance Survey mapping in the twentieth century. However, little has been written about the origins of the characteristic appearance of the first multi-colour editions, other that the Ordnance Survey used a military edition that was already in production. The distinctive style grew out of the work of a committee established in 1892 by the War Office to consider future army requirements for a map of the UK. This paper explores the work of the committee and its long-term implications for the look of mapping in the twentieth century.