共查询到20条相似文献，搜索用时 31 毫秒
1.
Abstract Many data structures are possible for the storage of topological information for computer-based maps. The PAN graph is here suggested as an aid in the selection of a strategy appropriate to the application. Examples are given for the mapping of triangular networks and Thiessen polygons. Application of the technique is appropriate to both education in, and design of, spatial data structures for automated cartography and geographical information systems 相似文献
2.
Presented are the technique and results of studying the landscape structure of the north-west of Western Siberia on the basis of the Hansen mosaic dataset consisting of elements covering the entire territory of the Earth. To study this area used a synthesis of classical methods of thematic system mapping as described in the doctrine of geosystems of V. B. Sochava, and automated interpretation of remote sensing data and mapping using GIS technologies. The method of geoinformational mapping of the landscape structure with the use of MultiSpec and Quantum GIS software programs for the purpose of drawing up real-time raster landscape maps is shown. In drawing up the map and the legend, the principle of geomic system-hierarchical representation of the territory as a complex multi-level “bottom-up” structure from topological-level geosystems (groups and classes of landscape facies) to regional-level geosystems (geoms, groups and classes of geoms) was used. Compilation of operational raster landscape maps of the north-west of Western Siberia involved multilevel automated interpretation of the Hansen mosaic dataset and mapping of areas (clusters) on images with different brightness characteristics, with the landscape structure of key areas and stationary physical and geographical profiles. A characteristic of this approach also implies using a dynamic classification of geosystems based on the study of their variable states. Such an approach permits a monitoring of changes in landscape structure and its areas and the intensity of anthropogenic impacts on forest and marsh landscapes, and determination of permissible pressure on geosystems in areas with high technogenic pressure of the oil and gas complex represented by the north-west of Siberia. An automated processing of data based on a supervised classification of territorial objects allows for the elimination of inaccuracies arising in visual image interpretation. Raster landscape maps can be used both for a further generation of vector maps and as a real-time information base for purposes of environmental management and protection. 相似文献
3.
Patrick Taillandier Cécile Duchêne Alexis Drogoul 《International journal of geographical information science》2013,27(12):1971-1999
Automating the generalisation process, a major issue for national mapping agencies, is extremely complex. Several works have proposed to deal with this complexity using a trial and error strategy. The performance of systems based on such a strategy is directly dependent on the quality of the control knowledge (i.e. heuristics) used to guide the trials. Unfortunately, most of the time, the definition and updation of knowledge is a fastidious task. In this context, automatic knowledge revision can not only improve the performance of the generalisation, but also allow it to automatically adapt to various usages and evolve when new elements are introduced. In this article, an offline knowledge revision approach is proposed, based on a logging of the system and on the analysis of outcoming logs. This approach is dedicated to the revision of control knowledge expressed by production rules. We have implemented and tested this approach for the automated generalisation of groups of buildings within a generalisation model called AGENT, from initial data that reference a scale of approximately 1:15,000 compared with the target map's scale of 1:50,000. The results show that our approach improves the quality of the control knowledge and thus the performance of the system. Moreover, the approach proposed is generic and can be applied to other systems based on a trial and error strategy, dedicated to generalisation or not. 相似文献
4.
Nicholas D. Arnold Denis White 《International journal of geographical information science》2017,31(12):2524-2542
Dot mapping is a traditional method for visualizing quantitative data, but current automated dot mapping techniques are limited. The most common automated method places dots pseudo-randomly within enumeration areas, which can result in overlapping dots and very dense dot clusters for areas with large values. These issues affect users’ ability to estimate values. Graduated dot maps use dots with different sizes that represent different values. With graduated dot maps the number of dots on a map is smaller, reducing the likelihood of overlapping dots. This research introduces an automated method of generating graduated dot maps that arranges dots with blue-noise patterns to avoid overlap and uses clustering algorithms to replace densely packed dots with those of larger sizes. A user study comparing graduated dot maps, pseudo-random dot maps, blue-noise dot maps and proportional circle maps with almost 300 participants was conducted. Results indicate that map users can more accurately extract values from graduated dot maps than from the other map types. This is likely due to the smaller number of dots per enumeration area in graduated dot maps. Map users also appear to prefer graduated dot maps over other map types. 相似文献
5.
WOLFGANG KAINZ 《International journal of geographical information science》2013,27(2):253-254
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. 相似文献
6.
Seyed Morsal Ghavami Mohammad Taleai Theo Arentze 《International journal of geographical information science》2017,31(5):1022-1041
This research presents an intelligent planning support system based on multi-agent systems for spatial urban land use planning. The proposed system consists of two main phases: a pre-negotiation phase and an automated negotiation phase. The pre-negotiation phase involves interaction between human actors and intelligent software agents in order to elicit the actors’ social preferences. The agents employ social value orientation theory, which is rooted in social psychology, in order to model actors’ social preferences. The automated negotiation phase involves negotiation among autonomous software agents, the aim being to achieve consensus about the spatial problem on behalf of the relevant actors and using the information obtained.
This study employs a computationally effective Bayesian learning technique, along with social value orientation theory, to design socially rational intelligent agents who work on behalf of real actors. The proposed system is applied to a real world urban land use planning case study. Human actors participate in a pre-negotiation phase, and their social preferences are elicited by intelligent software agents through a number of interactions. Then, software agents come together to engage in an automated negotiation phase and eventually reach an agreement on the spatial configuration of urban land uses on behalf of the actors. The results of the study show that the proposed system is effective at performing an automated negotiation, plus that the final plan – which is the output of the automated negotiation – produces higher social utility and better spatial land use configurations for the agents. 相似文献
7.
基于三维激光点云的复杂道路场景杆状交通设施语义分类 总被引：1，自引：0，他引：1
文章提出一种完整的全自动化处理框架,基于三维激光点云数据对高速公路和城市道路场景的杆状目标进行了检测和分类,主要包括3个步骤：数据预处理、杆状目标检测和分类。其中,在数据预处理阶段,采用基于布料模拟滤波算法自动分离地面点和非地面点,然后基于欧氏距离聚类方法对非地面点进行快速聚类,以及采用迭代图割算法进一步分割目标对象;在目标检测阶段,集成先验信息、形状信息和位置导向搭建滤波器,对杆状目标进行检测;在对象分类过程中基于多属性特征,利用随机森林分类器对目标的特征进行计算和分类。并使用3个道路场景数据集进行测试,结果显示,3个数据集的整体MCC系数为95.6%,分类准确率为96.1%。这说明文章所构建方法具有较高性能。另外,该方法还可以鲁棒地检测杆状目标的重叠区域,较为适应复杂程度不同的道路场景。 相似文献
8.
9.
Amy Hessl Jennifer Miller James Kernan David Keenum Don McKenzie 《The Professional geographer》2007,59(1):87-104
Fire history studies have traditionally emphasized temporal rather than spatial properties of paleo‐fire regimes. In this study we compare four methods of mapping paleo‐fires in central Washington from binary point data: indicator kriging, inverse distance weighting, Thiessen polygons, and an expert approach. We evaluate the results of each mapping method using a test (validation) dataset and receiver operating characteristic plots. Interpolation methods perform well, but results vary with fire size and spatial pattern of points. Though all methods involve some subjectivity, automated interpolation methods perform well, are replicable, and can be applied across varying landscapes. 相似文献
10.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(4):253-260
A statistical model for automated mapping of the spatial distribution of permafrost in the area of Corral del Veleta in south-east Spain (3703' N, 322' W; 3398 m a.s.l.) was developed and applied. The model uses a relationship between permafrost occurrence as indicated by BTS measurements, and variables such as altitude, solar radiation and summer snow cover. The model was implemented within a geographical information system (GIS) and determines the spatial distribution of probable permafrost in Corral del Veleta. Validation was achieved by comparing the predicted permafrost distribution with the results of recent fieldwork, such as geomorphic mapping, geophysical soundings and ground temperature logging. 相似文献
11.
A. L. O'Neill 《The Australian geographer》1989,20(1):26-36
Satellite imagery provides a cost effective method of mapping distinctive assemblages of landforms, soils and vegetation over large areas, especially where access is poor. This study reports on an evaluation of supervised and unsupervised techniques of classifying Landsat reflectance information in the Wiilandra Lakes World Heritage region. The accuracy of mapping derived from Landsat information compares very favourably with land systems mapping on the ground. 相似文献
12.
William J. Gribb Robert J. Czerniak John A. Harrington 《The Professional geographer》1990,42(4):471-480
Specifying the location of a rural residence is a common geographic problem. Most addressing systems are designed for urban areas and are not applicable to rural areas. The mile marker addressing system meets all of the requirements for a rural addressing system. With the addition of computer mapping techniques, rural addressing can be done efficiently and can provide the basis for a county's computer mapping system. Projects in New Mexico provide several examples of computerized rural addressing projects. 相似文献
13.
基于空间分形特征的城市群实体空间识别方法 总被引：1，自引：1，他引：0
城市群是城市地理学的重要研究领域,对城市群的实体空间进行界定识别是研究城市群的前提和基础。城市群作为众多城镇的集群,前人对城市群的空间识别主要是以城市为单元进行的,缺少对识别单元空间形态的考虑。城市群实体空间的形态具有自相似性,空间分形特征可作为自相似性的表征工具,通过对空间分形特征的分析、识别及提取,可以实现对空间对象基于形态的客观测度。本文借鉴单个城市其边界的相关识别方法,从不同尺度的空间最小可识别单元出发,测度城市群城镇空间形态的分形特征,并据此提出了城市群城镇的客观识别方法。该方法利用城镇的空间分形特征识别归属于城市群的城镇,通过空间最小可识别单元的变化得到不同的城镇规模并获取城市群城镇的空间分形特征,再以此为基础对空间分形特征的存在范围进行识别,将其映射于空间最终实现对城市群城镇的识别,进而得到城市群在空间上的分布状况。本文将该方法应用于京津冀城市群,基于2016年Landsat卫星遥感影像,实现了对京津冀城市群构成城镇的识别,为界定城市群的实体空间提供了一次有益尝试。 相似文献
14.
Timothy M. Cullen Richard E. Ll. Collier Robert L. Gawthorpe David M. Hodgson Bonita J. Barrett 《Basin Research》2020,32(5):1105-1139
Deep-water syn-rift systems develop in partially- or transiently-linked depocentres to form complicated depositional architectures, which are characterised by short transport distances, coarse grain sizes and a wide range of sedimentary processes. Exhumed systems that can help to constrain the tectono-stratigraphic evolution of such systems are rare or complicated by inversion tectonics. Here, we document a mid-Pleistocene deep-water syn-rift system fed by Gilbert-type fan deltas in the hangingwall of a rift margin fault bounding the West Xylokastro Horst block, on the southern margin of the Gulf of Corinth, Greece. Structural and stratigraphic mapping combined with digital outcrop models permit observations along this syn-rift depositional system from hinterland source to deep-water sink. The West Xylokastro Fault hangingwall is filled by two distinct sediment systems; an axial system fed by coarse-grained sediment gravity flows derived from fault-tip Gilbert-type fan deltas and a lateral system dominated by mass transport deposits fed from an evolving fault-scarp apron. Abrupt changes in stratigraphic architecture across the axial system are interpreted to record changes in relative base level, sediment supply and tectonics. Locally, depositional topography and intra-basinal structures controlled sediment dispersal patterns, from bed-scale infilling of local rugose topography above mass transport complexes, to basin-scale confinement from the fault scarp apron. These acted to generate a temporally and spatially variable, heterogeneous stratigraphic architecture throughout the basin-fill. The transition of the locus of sedimentation from a rift margin to a fault terrace through the syn-sedimentary growth of a basinward fault produced regressive surfaces updip, which manifest themselves as channels in the deep-water realm and acted to prograde the system. We present a new conceptual model that recognises coeval axial and transverse systems based on the stratigraphic architecture around the West Xylokastro fault block that emphasizes the lateral and vertical heterogeneity of rift basin-fills with multiple entry points. 相似文献
15.
Hospital service areas (HSAs) are increasingly adopted as a basic analysis unit for health care studies. The popular Dartmouth HSAs were produced more than two decades ago, and the process was far from automated. This research uses a Huff-based model automated in a geographic information systems (GIS) environment to delineate HSAs. Based on the Florida State Inpatient Database (SID) in 2011, a best-fitting distance decay function is derived from the actual travel patterns of hospitalization and then fed into the Huff model to strengthen the model's theoretical foundation in individual spatial behavior. The HSAs derived from the Huff-based model are then compared to the traditional flow-based HSAs defined by the Dartmouth method and assessed in terms of self-containment and heterogeneity of internal socioeconomic structure and urbanicity. The Huff-based model requires fewer data and is easy to implement as an automated toolkit and thus has great potential for replication in other regions to define large-scale and consistent HSAs. 相似文献
16.
E. A. Terekhin 《Geography and Natural Resources》2013,34(3):272-277
A case study has been made of the water bodies in Belgorod oblast in investigating the efficiency of improving spectral conversions of space images for purposes of automated interpretation of water bodies. A comparison is made of the initial image-based mapping accuracy of water bodies with values of 14 spectral indices. It is found that the Tasseled Cap Transformation can be employed in order to investigate in the greatest detail the spectral properties of water surfaces. Changes in the areas of water bodies of Belgorod oblast have been analyzed for the time interval from 1986 to 2011 on the basis of results of automated interpretation of space images. 相似文献
17.
生态地理区域系统的比较研究 总被引：18，自引：2，他引：16
生态地理区域系统通过对代表自然界宏观生态系统的生物和非生物要素地理相关性的比较研究和综合分析,按照自然界的地理地带分异规律,划分或合并而形成不同等级的区域系统。用中国的研究与国外同类研究的比较,可以拓宽这一领域的思路,便于在这一领域与国外的学者使用相似的科学语言进行学术交流,使中国这一领域的研究走向世界。本文从生态地理区域系统的发展过程、等级单位、指标体系与表达方法,区域划分等方面将中国有代表性的生态地理区域系统与国外同类研究进行比较,认为中外的研究有许多共同之处,如目标、研究内容和服务对象与环境、生态、全球变化等联系在一起,其中与美国R. Bailey所划分的美国、北美和全球生态地理区域更为接近,在等级系统、指标体系、表达方式到划分结果有近似之处。地域的差异,指标使用的不同,制图过程和表达方式的差异造成了区域划分的差别,似可以通过野外实地生态类型的辨识来加以修订。 相似文献
18.
An efficient and reliable automated model that can map physical Soil and Water Conservation (SWC) structures on cultivated land was developed using very high spatial resolution imagery obtained from Google Earth and ArcGIS®, ERDAS IMAGINE®, and SDC Morphology Toolbox for MATLAB and statistical techniques. The model was developed using the following procedures: (1) a high-pass spatial filter algorithm was applied to detect linear features, (2) morphological processing was used to remove unwanted linear features, (3) the raster format was vectorized, (4) the vectorized linear features were split per hectare (ha) and each line was then classified according to its compass direction, and (5) the sum of all vector lengths per class of direction per ha was calculated. Finally, the direction class with the greatest length was selected from each ha to predict the physical SWC structures. The model was calibrated and validated on the Ethiopian Highlands. The model correctly mapped 80% of the existing structures. The developed model was then tested at different sites with different topography. The results show that the developed model is feasible for automated mapping of physical SWC structures. Therefore, the model is useful for predicting and mapping physical SWC structures areas across diverse areas. 相似文献
19.
Developing approaches to automate the analysis of the massive amounts of data sent back from the Moon will generate significant benefits for the field of lunar geomorphology. In this paper, we outline an automated method for mapping lunar landforms that is based on digital terrain analysis. An iterative self-organizing (ISO) cluster unsupervised classification enables the automatic mapping of landforms via a series of input raster bands that utilize six geomorphometric parameters. These parameters divide landforms into a number of spatially extended, topographically homogeneous segments that exhibit similar terrain attributes and neighborhood properties. To illustrate the applicability of our approach, we apply it to three representative test sites on the Moon, automatically presenting our results as a thematic landform map. We also quantitatively evaluated this approach using a series of confusion matrices, achieving overall accuracies as high as 83.34% and Kappa coefficients (K) as high as 0.77. An immediate version of our algorithm can also be applied for automatically mapping large-scale lunar landforms and for the quantitative comparison of lunar surface morphologies. 相似文献
20.
《地理学报(英文版)》2017,(11)
Developing approaches to automate the analysis of the massive amounts of data sent back from the Moon will generate significant benefits for the field of lunar geomorphology.In this paper,we outline an automated method for mapping lunar landforms that is based on digital terrain analysis.An iterative self-organizing(ISO)cluster unsupervised classification enables the automatic mapping of landforms via a series of input raster bands that utilize six geomorphometric parameters.These parameters divide landforms into a number of spatially extended,topographically homogeneous segments that exhibit similar terrain attributes and neighborhood properties.To illustrate the applicability of our approach,we apply it to three representative test sites on the Moon,automatically presenting our results as a thematic landform map.We also quantitatively evaluated this approach using a series of confusion matrices,achieving overall accuracies as high as 83.34% and Kappa coefficients(K)as high as 0.77.An immediate version of our algorithm can also be applied for automatically mapping large-scale lunar landforms and for the quantitative comparison of lunar surface morphologies. 相似文献