Fundamental Theories of Spatial Similarity Relations in Multi-scale Map Spaces

Similarity relation is one of the spatial relations in the community of geographic information science and cartography.It is widely used in the retrieval of spatial databases, the recognition of spatial objects from images, and the description of spatial features on maps.However, little achievements have been made for it by far.In this paper, spatial similarity relation was put forward with the introduction of automated map generalization in the construction of multi-scale map databases;then the definition of spatial similarity relations was presented based on set theory, the concept of spatial similarity degree was given, and the characteristics of spatial similarity were discussed in detail, in-cluding reflexivity, symmetry, non-transitivity, self-similarity in multi-scale spaces, and scale-dependence.Finally a classification system for spatial similarity relations in multi-scale map spaces was addressed.This research may be useful to automated map generalization, spatial similarity retrieval and spatial reasoning.

Formula for calculating spatial similarity degrees between point clouds on multi-scale maps taking map scale change as the only independent variable

The degree of spatial similarity plays an important role in map generalization, yet there has been no quantitative research into it. To fill this gap, this study first defines map scale change and spatial similarity degree/relation in multi-scale map spaces and then proposes a model for calculating the degree of spatial similarity between a point cloud at one scale and its gener- alized counterpart at another scale. After validation, the new model features 16 points with map scale change as the x coordinate and the degree of spatial similarity as the y coordinate. Finally, using an application for curve fitting, the model achieves an empirical formula that can calculate the degree of spatial similarity using map scale change as the sole independent variable, and vice versa. This formula can be used to automate algorithms for point feature generalization and to determine when to terminate them during the generalization.

Disparity estimation for multi-scale multi-sensor fusion

The perception module of advanced driver assistance systems plays a vital role.Perception schemes often use a single sensor for data processing and environmental perception or adopt the information processing results of various sensors for the fusion of the detection layer.This paper proposes a multi-scale and multi-sensor data fusion strategy in the front end of perception and accomplishes a multi-sensor function disparity map generation scheme.A binocular stereo vision sensor composed of two cameras and a light deterction and ranging(LiDAR)sensor is used to jointly perceive the environment,and a multi-scale fusion scheme is employed to improve the accuracy of the disparity map.This solution not only has the advantages of dense perception of binocular stereo vision sensors but also considers the perception accuracy of LiDAR sensors.Experiments demonstrate that the multi-scale multi-sensor scheme proposed in this paper significantly improves disparity map estimation.

Coping with Multi-scale Climate Change:Study on the Application of Urban Environmental Climate Maps of Stuttgart,Germany

The development of modern cities has brought about tremendous changes in the climate environment.Faced with complex climate conditions,research on multi-scale climate change in cities is of great significance.The urban environmental climate maps and the application of climate atlas tool in Stuttgart,Germany were studied,and the multi-scale application of urban environmental climate maps in Stuttgart,Germany was summarized through the analysis of the pre-planning,current construction situation,and landscape reconstruction of the German"Stuttgart 21"plan case.Besides,other important measures to cope with climate change in German were proposed,and finally multi-scale practical strategies to cope with urban climate and environment were summarized to provide ideas and methods for improving China’s future urban climate environment.

The International Cartographic Association National Atlas Commission Meeting Held in Beijing

ICA National Atlas Commission held a commission meeting and symposium from August 8-12,1990 in Beijing.Among those present at the meeting were Dr.B.Rystedt(Sweden),Chairman of ICA,Dr.E.Ciekirska(Canada),Vice Chairman of ICA and members from U.S.A.,China,Spain,the Netherlands,Czechoslovakia,India as well as representatives from U.S.S.R.,Czechoslovakia,and Spain.40 Chinese cartographers attended the meeting.The major topics

Information Theory of Cartography:An Information-theoretic Framework for Cartographic Communication

Map is one of the communication means created by human being.Cartographers have been making efforts on the comparison of maps to natural languages so as to establish a"cartographic language"or"map language".One of such efforts is to adopt the Shannon’s Information Theory originated in digital communication into cartography so as to establish an entropy-based cartographic communication theory.However,success has been very limited although research work had started as early as the mid-1960 s.It is then found that the bottleneck problem was the lack of appropriate measures for the spatial(configurational)information of(graphic and image)maps,as the classic Shannon entropy is only capable of characterizing statistical information but fails to capture the configurational information of(graphic and image)maps.Fortunately,after over 40-year development,some bottleneck problems have been solved.More precisely,generalized Shannon entropies for metric and thematic information of(graphic)maps have been developed and the first feasible solution for computing the Boltzmann entropy of image maps has been invented,which is capable of measuring the spatial information of not only numerical images but also categorical maps.With such progress,it is now feasible to build the"Information Theory of Cartography".In this paper,a framework for such a theory is proposed and some key issues are identified.For these issues,some have already been tackled while others still need efforts.As a result,a research agenda is set for future action.After all these issues are tackled,the theory will become matured so as to become a theoretic basis of cartography.It is expected that the Information Theory of Cartography will play an increasingly important role in the discipline of cartography because more and more researchers have advocated that information is more fundamental than matter and energy.

The Cartography and the Spatial Representations:Search by Perfect Map

The activities of the professionals working on cartographic products have been highlighted especially in recent years. The history, the concepts and categories of cartography cannot be neglected in using this type of tool since the use of elements that make a cartographic product, as an example: map, chart, plan, globe, and a scale model should be used since the unawareness of techniques of cartography and the absence of the components of a map may hinder the understanding of what is intended to represent cartographically. This text is a contribution to the discussion of advances in cartography including errors and absence of maps, including a brief discussion of the characteristics of cartographic language nowadays and the search for perfection in cartography.

基于多分辨率地图位姿跳变优化的改进Cartographer算法

针对Cartographer算法在局部扫描匹配中,存在匹配精度低、位姿跳变影响回环检测的问题,提出一种基于多分辨率地图位姿跳变优化的改进Cartographer算法。首先,在局部优化中,建立多分辨率栅格地图,提高初始位姿的估计精度;然后,在回环检测和全局优化之间,建立位姿跳变检测机制,通过减少突变节点数量,提高回环检测的可靠性;最后,通过数据集中,对改进算法进行验证。结果表明:该算法能有效提高定位精度和建图效果。

基于MapGIS的洞庭湖区植被分布图的编制

为了掌握洞庭湖区植被类型现状、分布规律及变化特征,在对洞庭湖区植被类型分布现状进行全面调查的基础上,设计了具有洞庭湖区湿地特色的植被群落分类体系和编码,利用先进的GPS、G IS、计算机制图技术编绘了洞庭湖区第一幅数字化植被类型图,并建立了与图形数据库联动的属性数据库,为洞庭湖区的科学研究、环境保护和综合治理开发提供了宝贵的基础数据.

GeneMap软件在大比例尺地形图缩编中的应用

大比例尺数字化地形图在城镇建设中起着重要的作用,而传统地形图缩编技术效率较低。本文以北京市1∶2000数字化地形图缩编1∶10000地形图为例,充分利用GEOWAY GeneMap平台的缩编功能,采用基于规则库的一致性制图综合和交互式制图综合相结合的方法,缩编作业效率比较高,减轻了作业强度,提高了作业精度,为大比例尺地形图缩编提供了一种新的思路。

基于MapGIS编制城镇土地利用现状图的研究

阐述了城镇土地利用现状图的编制原则和编制方法。详细介绍了基于MapGIS软件下制作城镇土地利用现状图的步骤,并给出了实例。

Schematic Road Network Map Progressive Generalization Based on Multiple Constraints

Multiple constraints for schematic road network map cartographic design are analyzed and summarized. Based on this, a set of quantitative criteria are set up and a new road network generalization method including progressive selection and displacement is proposed. Furthermore, topological checking methods for road networks are researched. Based on these constraints, the points in a road network are classified, and a satisfactory and effective schematic map is designed in a con- crete experiment while maintaining topological consistency of the road network between the original and the schematic map

Honesty, power and bootstrapping in composite interval quantitative trait locus mapping

In a typical composite interval mapping experiment, the probability of obtaining false QTL is likely to be at least an order of magnitude greater than the nominal experiment-wise Type I error rate, as set by permutation test. F2 mapping crosses were simulated with three different genetic maps. Each map contained ten QTL on either three, six or twelve linkage groups. QTL effects were additive only, and heritability was 50%. Each linkage group had 11 evenly-spaced (10 cM) markers. Selective genotyping was used. Simulated data were analyzed by composite interval mapping with the Zmapqtl program of QTL Cartographer. False positives were minimized by using the largest feasible number of markers to control genetic background effects. Bootstrapping was then used to recover mapping power lost to the large number of conditioning markers. Bootstrapping is shown to be a useful tool for QTL discovery, although it can also produce false positives. Quantitative bootstrap support—the proportion of bootstrap replicates in which a significant likelihood maximum occurred in a given marker interval—was positively correlated with the probability that the likelihood maxima revealed a true QTL. X-linked QTL were detected with much lower power than autosomal QTL. It is suggested that QTL mapping experiments should be supported by accompanying simulations that replicate the marker map, crossing design, sample size, and method of analysis used for the actual experiment.

基于聚焦滤波的林业专题地图制图综合方法

森林资源规划设计调查成果总是以连续的面状图斑呈现。当大比例尺二类调查成果图缩编为更小比例尺地图时,常常需要制图综合。如何在制图综合时既要简化多边形边界,又要保持各类型林相面积和位置的相对不变,是林业专题制图的一个难题。经大量实验发现,将实施制图综合的连续面状图斑要素从矢量格式转换为栅格格式,经Focal滤波器以Majority方式滤波处理后,再将滤波后结果从栅格数据转换为矢量数据,可较好地实现森林资源专题连续面状要素信息的制图综合。以云南省某地一个1万hm^(2)的实验区为例,使用该方法将1∶2.5万的森林资源二类调查成果图缩编为1∶25万。结果表明,缩编后,多边形边界简化,目视效果较好,各类型林相面积变化绝对值平均为0.2%,位置精确度平均值为94.68%。此方法已应用于云南森林资源状况图集相关专题图等的生产实践。

基于GIS地图矢量化成果可用性提升下的地图制图数据组织模型设计

为了解决传统地图制图数据组织方法存在的不足和缺陷,提出一种基于地理信息系统(Geographic Information System,GIS系统)的地图矢量化成果可视化表达方法。该方法以ArcGIS平台为基础,利用ArcMap软件进行二次开发实现对地图矢量图层及属性信息的处理与分析功能;在此基础上,结合空间数据管理技术及面向对象分析理论,构建了一套适用于地理实体专题图件制作过程的地图符号库、注记库、符号库等数据库;并通过Web端的地图浏览器来实现各类专题图件的在线编辑、修改以及输出显示等操作。最后本文从多个方面阐述了基于GIS地图矢量化成果可视化表达的关键技术问题及其在实际工作中的应用情况,以期能够进一步提高地图制图数据组织效率,促进其向更高质量发展。

回环修正语义并结合三角定位的重定位算法

针对栅格地图的回环检测导致语义物体的映射产生偏移,Cartographer匹配定位算法在单一环境下定位速度慢甚至定位错误的问题,本文提出基于回环检测修正语义物体位置并结合三角定位的重定位算法。通过YOLOV5物体识别并结合Cartographer构建语义地图,基于回环检测修正语义地图中语义物体位置,基于语义地图结合三角定位对机器人预定位,基于预定位位姿进行Cartographer精定位。最后通过多组真实环境下的实验证明了该算法在大场景下定位速率相较于原始Cartographer重定位算法提升76.23%,并提升鲁棒性。

基于地图制图数据库的快速制图技术研究

地图成果在社会管理、经济发展、应急指挥等领域的需求增加,对快速制图提出了更高的要求。针对基于地图制图数据库的快速制图技术开展研究,制定制图规则和地图模板,设定符号体系,转换地理信息空间数据成为制图数据,完成地图整饰,最终批量、快速化生成地图产品。实例应用结果表明:与传统制图方法比较,批量成图生产的工作效率和产品质量都得到大幅度提升,达到了预期的效果。

地理空间认知视域下政务地图编制方法

目前虽然导航地图和电子地图被广泛应用,但传统地图因其确定尺度对用户空间认知更为友好,功能优势仍然突显。本文从地理空间认知出发,基于该领域相关理论和研究成果,结合对省级政务地图应用服务情况的分析,提出政务地图编制设计的方法:(1)在遵循地图综合原则下,地图要素选取、表达、图面设计和注记的针对性设计;(2)开展制图表达地理空间分区与制图等级划分的基本方法,以满足政务地图设计中地理要素可视化表达要求;(3)通过制图要素表达分级,优化地图数据结构,满足地图编制快速配置需要,以及多尺度成图快速制图或单一成图尺度自适应空间表达的需要。

1∶5万地图数据库的计算机综合缩编

针对国家空间数据基础设施建设的需求,讨论了实用化地图综合软件的开发与应用,从软件开发角度讨论了地图综合系统功能的层次化划分及在软件中的圈层式结构组织,地图综合操作环境的建立,综合规则的形式化表达,综合算子的设计与软件实现。结合1∶1万到1∶5万数字地图综合及更新的应用实例,提出了多尺度空间数据库建立的技术路线。

地图符号系统的设计与实现

设计并实现了一套地图符号系统 ,提出了线状符号的附属属性设置实现 ,并采用了程序符号的思想实现一些相对特殊的如沙丘、河流、沼泽等地图符号 ,成功地对国家标准系列地形图图式进行了设计 ,实现了各种比例尺下的地图符号的绘制 ,完成了在VisualC+ + 平台上所研制的地图符号软件系统的设计与开发。