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《制图学和地理信息科学》2013,40(3):205-224
Over the last three decades analytical cartography has grown from Tobler's concept of "solving cartographic problems" into a broader and deeper scientific specialization that includes the development and expansion of analytical/mathematical spatial theory and model building. In many instances Tobler himself has led the way to these new insights and developments. Fundamental concepts begin with Tobler's cartographic transformations; Nyerges' deep and surface structure and data levels; and Moellering's real and virtual maps; the sampling theorem; and concepts of spatial primitives and objects. This list can be expanded to include additional analytical concepts such as spatial frequencies, spatial surface neighborhood operators, information theory, fractals, Fourier theory, topological network theory, and analytical visualization, to name a few. This base of analytical theory can be employed to analyze and/or develop such things as spatial surfaces, terrain analysis, spatial data schemas, spatial data structures, spatial query languages, spatial overlay and partitioning, shape analysis, surface generalization, cartographic generalization, and analytical visualization. More analytical uses of theory, strategies of analysis, and implementations are being developed and continue to multiply as the field continues to grow and mature. A primary goal is to expand the mathematical/analytical theory of spatial data analysis, and theory building and analytical visualization as analytical cartography takes its place in the geographic information sciences. The research future for this area appears very bright indeed. 相似文献
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《制图学和地理信息科学》2013,40(3):159-161
The Spatial Oata Transfer Standard (SOTS) was approved as Federal Information Processing Standard (FIPS) 173, effective February 1993. Federal agencies and geographic information system vendors currently are developing SOTS encoding and decoding capabilities. A program is being developed to test encoders and decoders for conformance to the requirements of SOTS profiles. A series of test points will specify SOTS requirements that can be tested by software or by nonautomated methods. By certifying SOTS products, the conformance testing program will benefit both vendors and users of the SOTS. 相似文献
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《制图学和地理信息科学》2013,40(3):176-178
Australia and New Zealand are adopting the Spatial Data Transfer Standard (SDTS) as their transfer standard for geographic data. The standard requires a number of modifications to suit Australia/New Zealand requirements. These modifications primarily involve coordinate reference systems for each country, references to those standards applicable to each country and new spatial feature dictionaries. For other countries adopting SDTS, future revisions to the standard should emphasize a framework for required modifications. Australia/New Zealand have established a support body to ensure the smooth introduction of the standard within these countries. This commercial venture has been successful in promoting the standard, in providing training and in related consulting work. The US Geological Survey has been the maintenance authority for the standard. It is essential that this function continues to be provided through this body to guarantee a single interpretation of the standard. 相似文献
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《制图学和地理信息科学》2013,40(5):332-334
Dramatic changes in the way that spatial data have been collected and processed over that last 20 years is leading to a rethinking and restructuring on the most efficient ways to handle geographical information. These changes are taking place at the federal, state, and local governmental levels with great potential for the private sector as well. The formal adoption of the Spatial Data Transfer Standard (SDTS) as the federal database transfer standard for spatial databases signals a new era in this long chain of developments. It offers more flexible and efficient database transfers than earlier tools, and will become the workhorse for implementing the new National Spatial Data Infrastructure. It offers organizations a standard that will make possible and practical a much wider sharing of databases than is currently being done today. Use of the SDTS presents an opportunity to many organizations to share data more easily and reduce the duplication of expensive spatial database resources. 相似文献
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《制图学和地理信息科学》2013,40(3):171-202
This paper explains the performance of a map-reading task that required subjects to locate a state on a map of the United States after being given the state's name. Response times and accuracy were hypothesized to be a function of differences among the decision makers and among the states. The cognitive science literature suggests that variation in performance can be explained by the interaction of biological and environmental variables. Individual differences in gender, working memory capacity, and brain lateralization were hypothesized to affect performance of the spatial task. Results indicated gender could be a more informative variable than sex. Subjects, who identified with both feminine and masculine characteristics, had the fastest mean response times. Subjects, who did not identify with feminine or masculine characteristics, had the most accurate responses. Subjects who combined higher verbal and spatial working memory capacities had both the fastest and most accurate performances. The results supported other studies indicating a non-linear relationship relating sex, brain lateralization, and accuracy. Covariates related to gravity model variables were also significantly related to performance. 相似文献
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《制图学和地理信息科学》2013,40(1):11-19
Statistical maps are now produced in greater numbers and by persons in a wider range of disciplines than ever before. It is unfortunate that this increased production has not been accompanied by an improvement in map quality. All too frequently, contemporary mapmakers evidence a lack of understanding of the primary function of statistical maps, the symbolic language of mapping, and the effect that data manipulation plays in map communication. Coupled with these deficiencies there is a general lack of appreciation of the basic elements of graphic design. Furthermore, the expanded use of the computer in mapmaking seems to be related to and may even foster low quality since programmers are generally untutored in cartographic design and communication. 相似文献
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《制图学和地理信息科学》2013,40(3):222-224
On a previously-digitized map, a series of 685 points were screen-digitized so as to represent major spatial features of each polygon composing 17 forest types having inherently uncertain boundaries; three forest types having precise boundaries were treated as such. From these points and three exact types, surfaces were generated which provided weights of the certainty of having each of the 20 forest types at a location. These surfaces were “reconstituted” into a thematic map by assigning each location to the type having the highest weight. When compared to the precisely digitized and rasterized map, areal and locational inaccuracy were 5% and 18%, respectively, for the reconstituted thematic map. For certain situations—such as the preparation of long-term forest management plans—these results show promise for adequately representing maps of natural features while reducing digitizing efforts. 相似文献
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《制图学和地理信息科学》2013,40(2):139-152
This paper studies the role, impact, and effectiveness of geographic information technologies such as GIS. Contemporary frameworks—such as economic evaluation, organizational context, or diffusion—deal with some aspects only. Institutionalization of geographic information technologies is proposed as a paradigm for studying the impact and effectiveness more comprehensively. It refers to the ongoing process within a group or society whereby this technology itself is becoming institutionalized and gaining a strong (normative) impact on common perceptions of spatial problems and, subsequently, on collective actions to remedy these problems. Hence, it is a paradigm that encompasses value, as well as organizational and societal issues, and links these to the level of individual behavior patterns. The paradigm therefore may provide context for economic evaluation, organizational considerations, and diffusion, as well as for other interpretative perspectives. The paper outlines the concept of institutionalization of geographic information technologies and some of its salient factors and conditions. The focus is on feedback and participatory approaches in the design, and choice and implementation of geographic information technologies; whether these are institutionalized or not. Further (empirical) research is needed to explore the practical usefulness of the concept. 相似文献
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《制图学和地理信息科学》2013,40(2):78-95
The automation of map design is a challenging task for both researchers and designers of spatial information systems. A main problem in automation is the quantification and formalization of the properties of the process to be automated. This article contributes to the formalization of some steps in the processes involved in map design and demonstrates how the Shannon information theory (Shannon and Weaver 1964) can be used to compute an evaluation index of a map, i.e., a parameter which measures the efficiency of the map. Throughout this article, the term "information" is mostly used in a narrow sense and the application of information theory is restricted to the syntactic level of cartographic communication. Information sources for map entropy computations are identified and elaborated on. A special class of map information sources are defined and termed "orthogonal map information sources". Further, a strategy to consider spatial properties of a map in entropy computations is presented. At the end of the article, some examples demonstrate how the channel capacity and other entropy related measures can be computed and used to control automated processes for map design or map generalization. 相似文献