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1.
In this study, an empirical model for predicting urban evapotranspiration (ET) is examined for the Phoenix metropolitan area that is in a subtropical desert climate using in situ ET measurements from a local flux tower and remotely sensed moderate-resolution imaging spectroradiometer land products. Annual ET maps of Phoenix are then created for the period from 2001 to 2015 using the empirical model developed. A time-series trend analysis is finally performed using predicted ET maps to discover the spatio-temporal patterns of ET changes during the study period. Results suggest that blue-sky albedo and land surface temperature are two statistically significant variables explanatory to model urban ET for Phoenix. Areas that have experienced significant increases of ET are highly spatially clustered, and are mainly found on the outskirts of the city, while areas of decreasing ET are generally associated with highly developed areas, such as downtown Phoenix. 相似文献
2.
Estimates of solar radiation distribution in urban areas are often limited by the complexity of urban environments. These limitations arise from spatial structures such as buildings and trees that affect spatial and temporal distributions of solar fluxes over urban surfaces. The traditional solar radiation models implemented in GIS can address this problem only partially. They can be adequately used only for 2‐D surfaces such as terrain and rooftops. However, vertical surfaces, such as facades, require a 3‐D approach. This study presents a new 3‐D solar radiation model for urban areas represented by 3‐D city models. The v.sun module implemented in GRASS GIS is based on the existing solar radiation methodology used in the topographic r.sun model with a new capability to process 3‐D vector data representing complex urban environments. The calculation procedure is based on the combined vector‐voxel approach segmenting the 3‐D vector objects to smaller polygon elements according to a voxel data structure of the volume region. The shadowing effects of surrounding objects are considered using a unique shadowing algorithm. The proposed model has been applied to the sample urban area with results showing strong spatial and temporal variations of solar radiation flows over complex urban surfaces. 相似文献
3.
《The Cartographic journal》2013,50(3):233-241
AbstractThere have been numerous efforts over many years to map or delineate urban locations and features in the Kathmandu Valley of Nepal. This study acquired 27 land useland cover maps for the Valley or the urban portions of the Valley. Those maps vary greatly in their mapping parameters. The objectives of this study were to first conduct a cartographic comparison of the differences in the creation and content of the maps and then do an analysis of the urban changes in the Valley based upon the maps. The maps for the Valley have differed in their source materials, the amount of field work involved, scale and minimum mapping units, classifications used, definitions of classes and coordinate systems. Source materials have included various scales and formats of aerial photography and different satellite systems. The most difficult issue in comparing the maps is the varied classification systems and definitions. The same feature will be classified differently from map to map. This is particularly an issue for institutional features such as temples, palaces, educational facilities, open public space and governmental sites. Definitions of residential areas are also not consistent. Even with the differences in mapping parameters, considerable useful information can be obtained by comparing these maps. These include a simply documentation of the urban extent and the generally resulting loss in agricultural lands. There was an increase in urban extent from 22 to 83km2 between 1955 and 2000. Urban expansion has also changed from occurring on the upland river terraces or tars to the floodplains. Finally, while not directly documented in these maps, the tremendous pace of urban growth has resulted in multiple infrastructure and environmental challenges. 相似文献
4.
针对整个城市规划过程的参与者对规划数据的不同种类、不同层次认知需求,本文利用本体思想对包括GIS数据、规划文档、规划图件等多源异构的规划数据进行关系重构,设计本体模型要素的数据语义关系,定义数据间的关联关系,实现基于本体方法的规划领域语义表达算法,方便了各类规划参与者对规划方案认识的交流：同时根据用户特征分类,进行本体关系的逻辑推理,过滤冗余信息,进行多源异构规划数据的可视化。 相似文献
5.
地图是城市面貌最直观的反映,通过它不仅能够微观表示城市规划、建设、发展、变化,而且能够反映历史、人文、风土、人情。本文以"美丽江城幸福武汉"为主题,充分挖掘地理信息资源,按照系列化的设计思路,从不同的角度设计专题,将武汉全方位呈现在读者面前。 相似文献
6.
《地理信息系统科学与遥感》2013,50(1):48-67
This paper presents a new approach to improving land use/cover mapping accuracy in an urban environment. Bi-temporal Landsat TM images (1987 and 1997) were initially classified using the ISODATA method. An NDVI difference image was derived and classified, with each class indicating certain land use/cover changes. Temporal logical reasoning was then performed on the classified NDVI difference map and the initial land use/cover maps. The procedure successfully resolved the confusion between forest clear-cuts/fallow cropland and urban, as well as between forest clear-cuts and cropland. The kappa analysis test led to a Z value of 1.837 with the p-value of 0.026 for the year 1987, and a Z value of 1.924 with the p-value of 0.014 for 1997, indicating significant enhancement at the 95% confidence level. 相似文献
7.
ABSTRACTThis paper provides a study of the changes in land use in urban environments in two cities, Wuhan, China and western Sydney in Australia. Since mixed pixels are a characteristic of medium resolution images such as Landsat, when used for the classification of urban areas, due to changes in urban ground cover within a pixel, Multiple Endmember Spectral Mixture Analysis (MESMA) together with Super-Resolution Mapping (SRM) are employed to derive class fractions to generate classification maps at a higher spatial resolution using an Artificial Neural Network (ANN) predicted Wavelet method. Landsat images over the two cities for a 30-year period, are classified in terms of vegetation, buildings, soil and water. The classifications are then processed using Indifrag software to assess the levels of fragmentation caused by changes in the areas of buildings, vegetation, water and soil over the 30 years. The extents of fragmentation of vegetation, buildings, water and soil for the two cities are compared, while the percentages of vegetation are compared with recommended percentages of green space for urban areas for the benefit of health and well-being of inhabitants. Changes in Ecosystem Service Values (ESVs) resulting from the urbanization have been assessed for Wuhan and Sydney. The UN Sustainable Development Goals (SDG) for urban areas are being assessed by researchers to better understand how to achieve the sustainability of cities. 相似文献
8.
B. B. Serapinas 《地理信息系统科学与遥感》2013,50(4):247-255
The author outlines a method for quantitative analysis of the completeness of information presented on maps of varying scale, i.e., for determining, upon reductions in scale of an original map A, what magnitudes of loss in graphic detail will result in derivative maps B, C, D that are of equal relative completeness to the original. Empirical formulae are derived which describe intensities of selection typical of maps devoted to particular topics (stream networks, urban socioeconomic indices, etc.) and graphic methods are described which can be used to determine scale denominators at which specific reductions in the number of features can occur without losses in “completeness” or, conversely, the number of particular kinds of features that can be eliminated on maps (or portions of maps) upon reductions in scale without losses in completeness. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1985, No. 5, pp. 17–23. 相似文献
9.
none 《The Cartographic journal》2013,50(1):68-73
AbstractNavigation around urban areas is often constraining for the mobility-impaired due to the fabric of the urban landscape, and there is a need to provide maps tailored to individual abilities. Barriers to effective navigation, such as slope, surface type and dropped kerbs, differ for able-bodied pedestrians and wheelchair users. This study identifies and quantifies such differences, and develops a Geographical Information Systems (GIS) network model for the creation of accessibility maps for wheelchair users. The measurement of barriers uses Digital Elevation Models, calculation of rolling resistance, and surveys in the field using hand-held GIS. A spatial database has been constructed which contains the pedestrian route network and barriers to navigation. A GIS application runs the model, providing a user-friendly interface to define and calculate routes through the pedestrian route network that take account of impedances to accessibility. The model, application and interface has been tested with wheelchair users and the route selection provides a good correspondence with patterns of route finding already established through experience. The interface and individually tailored maps generated, provide a tool suitable to assist wheelchair users new to an area; to enable better navigation for existing users, and a means for planners to consider the way in which access is restricted for wheelchair users in their designs for more inclusive urban environments. 相似文献
10.
An article devoted to applied forest-fire mapping outlines principles for the compilation of maps depicting “raw materials” for such fires. Various types and densities of vegetation cover are classified in terms of combustibility, i.e., according to the intensity of burning expected once they are fully exposed to flames. These maps are used in conjunction with weather data and forecasts to predict and combat the spread of fire across an area. Particular attention is devoted to identification and mapping of “basic conductors” of combustion–layers of forest litter and mossypeaty vegetation along which a forest fire normally spreads. Translated from: Geografiya i prirodnyye resursy, 1987, No. 3, pp. 138-144. 相似文献
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A method for the compilation of 1:3,000,000-scale maps of natural nival-glacial phenomena is proposed for an area of the High Pamir Range in Soviet Central Asia. Such maps depict the distribution, frequency and intensity/magnitude, and potential impacts of such natural hazards as avalanches, mudslides, “dirty snow” avalanches (combined avalanches-mudslides in late spring), icings (naledy), and glacier pulsations, and are used in the planning of construction and the maintenance of roads and other transportation corridors during winter and spring. Hypothetical examples of the use of the maps are provided. Translated from: Materialy glyatsiologicheskikh issledovanly, USSR Geophysical Committee Publication No. 55. Moscow: Mezhduvedomstvenniy geofizicheskiy komitet, 1986, pp. 213–219. 相似文献
13.
The World Atlas of Snow and Ice Resources, scheduled for publication in the late 1980s, is an extensive cartographic summary of current knowledge about snow and ice. Roughly 750 maps organized under 17 broad themes cover topics such as glacier morphology, temperature and precipitation conditions in glacier formation, avalanches, meltwater runoff, sea ice, and past glaciation. The organization of the project is described along with the contents of major thematic sections, and examples of the use of basic initial maps to validate information used in more complex derivative maps are provided. Translated from: Materialy glyatsiologicheskikh issledovaniy, USSR Geophysical Committee Publication No. 51. Moscow: Mezhvedomstvenniy geofizicheskiy komitet, 1984, pp. 89-95. 相似文献
14.
Mapping fine‐scale urban housing prices by fusing remotely sensed imagery and social media data 
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下载免费PDF全文 The accurate mapping of urban housing prices at a fine scale is essential to policymaking and urban studies, such as adjusting economic factors and determining reasonable levels of residential subsidies. Previous studies focus mainly on housing price analysis at a macro scale, without fine‐scale study due to a lack of available data and effective models. By integrating a convolutional neural network for united mining (UMCNN) and random forest (RF), this study proposes an effective deep‐learning‐based framework for fusing multi‐source geospatial data, including high spatial resolution (HSR) remotely sensed imagery and several types of social media data, and maps urban housing prices at a very fine scale. With the collected housing price data from China's biggest online real estate market, we produced the spatial distribution of housing prices at a spatial resolution of 5 m in Shenzhen, China. By comparing with eight other multi‐source data mining techniques, the UMCNN obtained the highest housing price simulation accuracy (Pearson R = 0.922, OA = 85.82%). The results also demonstrated a complex spatial heterogeneity inside Shenzhen's housing price distribution. In future studies, we will work continuously on housing price policymaking and residential issues by including additional sources of spatial data. 相似文献
15.
V. A. Musatov 《地理信息系统科学与遥感》2013,50(4):305-313
Shortcomings in the representation of bottom relief features on topographic maps of the continental shelves are examined, with particular attention given to submarine ridges and related features, the symbolization of which on such maps has been entirely ineffective. Specific recommendations are given on the form and color of symbols which can be used in upgrading the graphic impact of maps depicting such relief forms. Translated by Edward Torrey, Alexandria, VA 22308 from: Geodeziya i kartografiya, 1989, No. 1, pp. 35–40. 相似文献
16.
A. M. Berlyant 《地理信息系统科学与遥感》2013,50(3):214-223
Principles and objectives governing Soviet thematic mapping of nearby planets are outlined, types of information sources for such mapping categorized, and the suitability of different types of information sources for thematic mapping are evaluated. This is followed by a classification of thematic planetary maps according to type. The need for a standardized, systems approach to the determination of map scales, compilation and generalization, symbolization, and map design is emphasized as an essential prerequisite for the development of complex atlases of individual planets, atlases of “comparative planetology,” and the establishment of “planetary information systems.” Translated by Jay Mitchell; PlanEcon, Inc.; Washington, DC 20005 from: Vestnik Moskovskogo Universiteta, geografiya, 1987, No. 6, pp. 60-67. 相似文献
17.
A. A. Lyutyy 《地理信息系统科学与遥感》2013,50(2):103-117
The author, head of the Department of Cartography at the Institute of Geography, analyzes the language of maps in terms of general semiotic principles. Using the similarity of processes in other language systems, he constructs a model of the language of maps that distinguishes two sublanguages, one reflecting the locational aspects of maps (coordinate grids, etc.), the other reflecting the map content. The discussion touches on the system of map symbols as a linguistic feature, analyzes the system of map language in terms of such linguistic features as vocabulary, grammar and syntax, and draws other analogies between the language of maps and other language systems. Translated from: Voprosy Geografii, No. 122/123, 1984, pp. 40-56. 相似文献
18.
ABSTRACTFigures such as maps and time series are essential means to visualize spatiotemporal results in scientific papers. Being able to recompute them using the underlying source code and data is thus a core aspect in reproducible research. However, many scientists see the preparation of code and data for publication as an additional burden without immediate benefits. In this work, we investigate advantages and new capabilities of reproducible research papers. Our key contributions are (i) the extension of a geoscientist’s workflow while examining papers including reproducible figures such as maps and (ii) the prototypical implementation of the workflow as a web application. The workflow is based on current practices of geoscientists and encapsulates benefits of reproducible figures. It is informed by ideas and needs identified by geoscientists in a survey, interviews, and a focus group. Based on their statements, we first extend the traditional workflow steps Discovery and Inspection by additional capabilities and propose two new steps: Manipulation of the content of a spatiotemporal figure and Substitution of the underlying code and data. The extended workflow and its implementation might facilitate in-depth examination and reusability of geoscientific results. 相似文献
19.
A. L. Revzon 《地理信息系统科学与遥感》2013,50(1):44-52
Fault tectonics (i.e., frequency and intensity of faulting) is proposed as a leading factor governing the spatial distribution of exogenous processes which hinder construction activity (landslides, caveins, general subsidence, karst formation, etc.). This relationship provides the theoretical basis for compilation of engineering geomorphology maps which forecast the probability that such processes will occur in particular locations. Interpretation of space imagery at a variety of scales provides the raw date needed to test this relationship and compile the maps themselves. Sample maps prepared for river diversion and railroad construction projects are provided. Translated from: Geomorfologiya, 1984, No. 3, pp. 36-43. 相似文献
20.
The positional error in spatial data is defined as a vector by comparing the coordinates between the true position and the measured position. The standard tests to assess the positional accuracy use only the magnitude of the vector and omit the azimuth. This article suggests that the use of both values allows a much more complete analysis of the positional error. A set of tests is proposed that are relevant for this purpose and demonstrate that some important features are not identified by the common procedures. The test samples come from two datasets. The first is obtained from the comparison of 100 homologous points in two conventional maps, and the second one comes from the geometric calibration of a photogrammetric scanner. The results are analyzed and discussed, showing that important issues such as error anisotropy are detected only by means of the circular statistics tests and density maps of distribution. Therefore, tests that assess the goodness of fit for uniform distribution in azimuths, such as Rayleigh and Rao tests, give low probabilities (P = 0 and P > 0.01). Moreover, density maps working with both magnitude and angle can locate the outlier candidate and offer more information about the spatial distribution of error. 相似文献