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1.
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.  相似文献   

2.
The accuracy of old maps can hold interesting historical information, and is therefore studied using distortion analysis methods. These methods start from a set of ground control points that are identified both on the old map and on a modern reference map or globe, and conclude with techniques that compute and visualise distortion. Such techniques have advanced over the years, but leave room for improvement, as the current ones result in approximate values and a coarse spatial resolution. We propose a more elegant and more accurate way to compute distortion of old maps by translating the technique of differential distortion analysis, used in map projection theory, to the setting where an old map and a reference map are directly compared. This enables the application of various useful distortion metrics to the study of old maps, such as the area scale factor, the maximum angular distortion and the Tissot indicatrices. As such a technique is always embedded in a full distortion analysis method we start by putting forward an optimal analysis method for a general-purpose study, which then serves as the foundation for the development of our technique. Thereto, we discuss the structure of distortion analysis methods and the various options available for every step of the process, including the different settings in which the old map can be compared to its modern counterpart, the techniques that can be used to interpolate between both, and the techniques available to compute and visualise the distortion. We conclude by applying our general-purpose method, including the differential distortion analysis technique, to an example map also used in other literature.  相似文献   

3.
For the evaluation of results from remote sensing and high-resolution spatial models it is often necessary to assess the similarity of sets of maps. This paper describes a method to compare raster maps of categorical data. The method applies fuzzy set theory and involves both fuzziness of location and fuzziness of category. The fuzzy comparison yields a map, which specifies for each cell the degree of similarity on a scale of 0 to 1. Besides this spatial assessment of similarity also an overall value for similarity is derived. This statistic corrects the cell-average similarity value for the expected similarity. It can be considered the fuzzy equivalent of the Kappa statistic and is therefore called KFuzzy. A hypothetical case demonstrates how the comparison method distinguishes minor changes and fluctuations within patterns from major changes. Finally, a practical case illustrates how the method can be useful in a validation process.  相似文献   

4.
Abstract

Recent developments in geographical information systems have drawn upon concepts of fuzzy set theory and multi-criteria methodology. In this paper we argue that there is a method, Saaty’s Analytic Hierarchy Process (AHP), that is compatible with both these research directions. The contributions of the AHP are highlighted in the light of recent developments in GIS, with particular attention to the concept of fuzzy set theory. An example of a GIS application is provided to show how the AHP can deal operationally with fuzziness, factor diversity and complexity in problems of land evaluation involving the location of a public facility.  相似文献   

5.
Social science literature suggests that neighborhood-based visual cues have substantive effects on individuals' littering behaviors. Experimental research on this topic typically alters the appearance of a selected public location, and then monitors changes in littering due to these tightly controlled esthetic changes. The general finding is that littering occurs more frequently in relatively disorderly settings. The current paper extends this work by testing whether or not the same finding holds in more “real life” situations, wherein the operative visual cues come directly from the environment rather than through experimental manipulation. Specifically, the paper empirically identifies two study sites that serve similar functions in their urban system, but that differ markedly in contextual features. At the first site (#1), visual cues include liquor stores, vacant structures, and a noisy interstate highway. Notable visual cues at site #2 are scenic vistas, well-maintained housing, and greenspaces. When the same quasi-natural littering experiment was conducted at both locations, the littering rate was significantly higher at site #1 compared to site #2 (after controlling for individual-level demographic attributes). This result adds value to the applied geography community, as it confirms that spatially-based attributes do influence individual behaviors in a manner consistent with controlled, comparatively acontextual experimental findings. Additionally, the results implicate policy strategies that might be useful for counteracting antisocial urban behavior.  相似文献   

6.
分析了工业区工业企业成组布局与分散布局相比较的经济效果,并采用年费用指标作为评价成组布局经济效果的基本指标。本文还分析了工业成组布局的经济效果与工业区规模之间的关系。本文以年费用最小为目标函数,以成组布局工业区的一些主要企业(基本企业)和与其相应的具有替代关系的分散布局企业(对比企业)为变量,建立了工业成组布局经济效果及最佳规模优化模型。  相似文献   

7.
Mental Maps and Fuzziness in Space Preferences*   总被引:1,自引:0,他引:1  
Mental maps are widely used to represent aggregate residential preferences in a population. This study examines the contention by researchers that the dominant viewpoint in a group in terms of residential desirability is not affected by the fuzziness in individual space preferences. Results indicate that a significant misrepresentation of group preferences can result when fuzziness of individual preferences is overlooked. The use of ordinal scales to generate mental maps is likely to distort the actual pattern of residential preferences that dominates in the group because of the failure of the ranking approach to account for imprecision and ambiguity in individual preferences. Because interval scales used in rating or evaluating tasks do not force individuals to give a crisp judgement of places, they are more adequate than ordinal scales for mental mapping and for behavioral analysis.  相似文献   

8.
Many of the techniques used to describe the location of human activities incorporate physical definitions of distance and area, although other definitions are methodologically preferable. Using Boone County, Missouri as an example, the physical-distance regularity of city spacing is described by the nearest-neighbor statistic, modified to compensate for boundary effect. The statistic is reformulated with an estimate of temporal area, defined by analogy with shape-compactness measures, and travel times. Application of the refined formula reveals greater regularity of city spacing in functional space than in physical space.  相似文献   

9.
A quantitative procedure for analyzing and comparing distortion in mental maps is presented. Using a microcomputer and digitizer, and by developing a distortion index, comparisons are made by direct analysis of mental maps. A case study of the mental maps of Israel of high school and university students showed a tendency to generalize shape to simple geometric forms, with foreshortening of north-south lines and exaggeration of east-west distances.  相似文献   

10.
The mental images on which an individual bases spatial decisions are often distorted versions of real-world geography. Distortion in these images is studied by extracting paired distance estimates and by requesting a sketch of a place drawn from memory. Reliance upon either technique to elicit large-scale spatial information assumes that distortion in the congnitive map is not introduced by the technique (sketching or configuration) used to construct it. Both techniques have been used in this study to produce cognitive maps for a common set of landmarks in Seattle. Map distortions are analyzed and compared to determine that significant differences result from the technique used.  相似文献   

11.
以城市区位论为主线,提出区位选择的分形思想和方法,旨在探讨人文地理系统空间优化的基本理论。指出区位选择和空间优化应该遵循三个基本原则:自相似原则、匹配原则和包容原则。  相似文献   

12.
The adoption of hazard mitigation measures by those in vulnerable areas is the result of a complex process involving many variables. This study investigates the potential impact one variable, location, has on adoption. The findings suggest that adoption of measures that require little planning and are highly visible are related to location.  相似文献   

13.
We describe a method of morphometric characterisation of landform from digital elevation models (DEMs). The method is implemented first by classifying every location into morphometric classes based on the mathematical shape of a locally fitted quadratic surface and its positional relationship with the analysis window. Single‐scale fuzzy terrain indices of peakness, pitness, passness, ridgeness, and valleyness are then calculated based on the distance of the analysis location from the ideal cases. These can then be combined into multi‐scale terrain indices to summarise terrain information across different operational scales. The algorithm has four characteristics: (1) the ideal cases of different geomorphometric features are simply and clearly defined; (2) the output is spatially continuous to reflect the inherent fuzziness of geomorphometric features; (3) the output is easily combined into a multi‐scale index across a range of operational scales; and (4) the standard general morphometric parameters are quantified as the first and second order derivatives of the quadratic surface. An additional benefit of the quadratic surface is the derivation of the R 2 goodness of fit statistic, which allows an assessment of both the reliability of the results and the complexity of the terrain. An application of the method using a test DEM indicates that the single‐ and multi‐scale terrain indices perform well when characterising the different geomorphometric features.  相似文献   

14.
大宗物质供销区位的定量分析及其引伸   总被引:2,自引:1,他引:2  
大宗物资供销区位的一般提法是:设有某大宗物资(如粮食、煤炭、原油),其产地是A_1, A_2,……,A_m,共m个,产量分别是a_1,a_2,……,a_m个单位(如 t,10~4×0.5kg);另有n个销地B_1,B_2,……B_n,销量分别为b_1,b_2,……,b_n。产销是平衡的,同时产地与销地之间的运输距离与运输方式已知,即单位货物的运输费用已知。  相似文献   

15.
《Urban geography》2013,34(3):243-257
The 50 largest firms headquartered in Pittsburgh were surveyed to examine the effects of telecommunications technology on office location. The results indicate that modern telecommunications and computer technologies will accelerate the deconcentration of office activities and that the traditional centrality of downtown will weaken. Financial institutions influenced by telecommunications in their locational decisions are more likely to decentralize their headquarters functions from the CBD than are other firm types. Large firms which use more advanced telecommunications technology are influenced more by the telecommunications factor when making their locational decisions. Use of more sophisticated telecommunications technology decreases the benefits of a CBD location, making it costlier to stay at a CBD location relative to a non-CBD location.  相似文献   

16.
ABSTRACT. The United States produces less than half of the oil it consumes, a dependence unlikely to subside without drastic improvements in domestic production, development of renewable resources, and greater energy efficiency. All three of these actions, even if ultimately meaningful, will take time to produce results, so the United States is likely to continue to depend on outside suppliers. The most tempting of these suppliers is Canada, especially its massive oil sands in northeastern Alberta Province. In this article I ask why that is true and, more important whether the arrangement is mutually beneficial. The answers are strongly related to location; that is, the location of supply and the location of demand. The view from the south favors Canada above all other countries as a likely source for meeting the growing U.S. oil needs, yet not without accompanying unintended consequences. When viewed from the north, the monetary attraction of the oil sands is weakened by the environmental costs that are likely if their development expands as expected. Weighing these perspectives, the question is whether the combination of demand and environmental concerns leads to, accelerates, or discourages development. Viewing such a prospect from both sides of the border challenges the view that development of natural resources is always inevitable or wise, regardless of apparent profitability and need. Much depends on location.  相似文献   

17.
港澳地区对中国内地直接投资的区位选择及其空间扩散   总被引:29,自引:3,他引:29  
贺灿飞  陈颖 《地理科学》1997,17(3):193-200
对港澳地区在中国内地直接投资的空间分布及其空间转移做了上分析,表明了港澳地区对中国内地的直接投资趋向于沿海地区和与这这有特殊社会文化联系的区位,同时更有向中西部和北部转移的趋势,决定港澳地区对中国内地投资空间模式和转移态势的因素是经济规模,经济增长速率,劳动力因素,经济开放度,与沿海的经济距离等。  相似文献   

18.
乡村旅游区选址问题研究 --以昆明市为例   总被引:5,自引:1,他引:5  
和一般旅游区一样,乡村旅游区具有满足旅游者不同需求的功能要素,由多个乡村旅游园区组成。在对昆明市周边乡村旅游区调查的基础上,对乡村旅游区的选址问题进行了探讨。与依托城市的时空距离、乡村旅游地的整体经济水平、农村特色和自驾车旅游是乡村旅游发展的4个背景条件。乡村旅游区选址受宏观和微观两个层次因子的影响:依托城市的出游能力、乡村旅游区的交通区位、旅游区位是3个宏观因素,乡村旅游区的聚集与屏蔽、乡村园区的周边环境状况是两个微观因素。最后从政策因素和旅游者品位变化的角度提出了影响乡村旅游区选址问题的两点补充意见。  相似文献   

19.
阐述了地衣形态量计法的基本原理和各种不同的具体量计方法及其在同震滑坡研究中的应用方法,指出将该方法应用于同震滑坡研究中,可以帮助提供地震时间、震中、地震频度、地震影响范围和地震断层的一些信息.  相似文献   

20.
The critical need to consider all options in the search for groundwater in semi-arid areas has promoted work on the possible association of near-surface groundwater and vegetation characteristics using a combination of remote-sensing data and geographic information systems (GIS) techniques. Two vegetative criteria (dense woody cover and abundance of deep-rooting species) are identified as being indicative of near-surface groundwater, and their spatial distribution is tested against the location of aquifers in southeast Botswana. Vegetative criteria classes were combined in a GIS environment with the distribution of geomorphic units and bedrock geology to determine the degree of coincidence with assumed or known aquifers. Results indicate that the distribution of dense woody vegetation as mapped from Thematic Mapper imagery has some potential in identifying especially surficial but also bedrock near-surface groundwater sources in mostly naturally vegetated semi-arid areas. Dense woody cover classes tend to select aquifers in topographically higher areas while classes comprising some deep-rooting species tend to select low-lying aquifers such as those occurring in fossil valleys. Deep-rooting species, however, are less successful as a vegetative criterion. Although various technical refinements are suggested, this work shows that vegetative criteria mapping can however be used in conjunction with conventional geological/geophysical techniques to enhance the prospects for groundwater location in relatively undisturbed semi-arid areas.  相似文献   

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