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681.
A paper devoted to the transformation of cartographic images based on nontraditional systems of scaling (travel time, transport effort, cost, etc.) describes the results of work to develop a more effective algorithm for such transformations, i.e., one which the authors claim provides for the more accurate determination of “transformed” line lengths than possible with earlier methods. Translated from: Izvestiya AN SSSR, seriya geograficheskaya, 1987, No. 4, pp. 105-111. 相似文献
682.
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
683.
Spectral reflectances of artificial pastures are examined at various wavelengths and stages in the grazing/field work cycle to identify inadequately drained, marginally productive sites. Mesophytic pasture grasses and crops on well-drained sites are replaced by more hygrophytic species on poorly drained sites (each group with distinctive brightness values). This relationship, plus less significant spectral differences reflecting grazing intensity and soil moisture content at particular points in time, provided a methodological basis for the study. Poorly drained pastures are most reliably identified in the infrared and visible green portions of the spectrum during the middle of the grazing season. Translated from: Geografiya I prirodnyye resursy, 1988, No. 1, pp. 134-139. 相似文献
684.
An effort is made at developing a theory of map readability, defined as the process of the user's representation of the information of the map in his/her own mind. This can be estimated quantitatively by surrogate measures, which include the speed of map comprehension and accuracy of map interpretation. Levels of psychological representation of map information are incorporated to determine at what stage particular aspects of map knowledge are understood. Thus what readability entails, and the approaches used to measure it (what types of things are comprehended, how fast, and how accurately) will depend upon the level of representation. Translated from: Vestnik Leningradskogo Universiteta, seriya 7 [geologiya, geografiya], 1988, No. 1, pp. 32-37. 相似文献
685.
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
686.
687.
P. D. Gunin Ye. A. Vostokova A. Ya. Druk N. I. Dorofeyuk Yu. G. Yevstifeyev Yu. N. Krasnoshchekov 《地理信息系统科学与遥感》2013,50(1):71-76
This paper explores how such characteristics as the polarization of reflected radiation, the angular characteristics of its reflectance, and its thermal properties can be used to supplement conventional remote sensing studies of the condition of the vegetation cover. One possible application is clarified by means of an experiment testing the relationship between the degree of polarization of radiation reflected from cultivated cotton fields and the condition of the crop in those fields. Empirical data demonstrate that changes in the geometric structure of (and reflectance from) fields occurs when cultivated plants are subjected to stress (disease or moisture deprivation). Translated by Edward Torrey, Alexandria, VA 22308 from: L. N. Vasil'yev, ed., Kosmicheskiye metody izucheniya biosfery [Remote Sensing Methods in the Study of the Biosphere]. Moscow: Nauka, 1990, pp. 77–82. 相似文献
688.
Two general approaches for compiling maps of components of the water-ice budget in regions of glacier nourishment are compared and the resulting maps are analyzed. The compilation of raw data is based on field measurements rather than remote sensing information. Translated by Edward Torrey, Alexandria, VA 22308 from: Materialy glyatsiologicheskikh issledovaniy, 1991, No. 72, pp. 94-102. 相似文献
689.
A. G. Repin 《地理信息系统科学与遥感》2013,50(4):342-351
The article provides insights derived from conceptualization of the totality of elements (subsystems) of image interpretation as part of a larger system of scientific research. Among the elements discussed in some detail in terms of their impacts on the appearance of features interpreted on remote sensing imagery include solar radiation, the atmosphere, distinctive characteristics of the surface of the area being imaged, the remote sensors employed for image recording, processing techniques, the image medium, and the “human” element (interpreter). It then describes an evolutionary process in image interpretation by which knowledge gained in early stages represents an input leading to refinement of approaches employed in later stages. A final section describes factors contributing to dynamics (“scintillation” or “flickering”) of features on imagery of the same area but recorded at different times or under different imaging conditions. Translated by Edward Torrey, Alexandria, VA 22308 from: Izvestiya Akademii Nauk, seriya geograficheskaya, 1993, No. 3, pp. 102-109. 相似文献
690.
Results are presented of analysis of Landsat MSS imagery for the purpose of assessing damage to northern taiga and tundra vegetation caused by emissions generated by nonferrous metallurgy on northwest Russia's Kola Peninsula. Unlike earlier studies, the present project attempts to provide spatially comprehensive coverage of vegetation impacts, according to a standardized methodology for their assessment. A reduction in the number of feature classes identifiable upon a change from visual interpretation to automated classification based on spectral brightness values made it necessary to test alternative classification procedures (based on brightness ratios and the normalized vegetation index). 相似文献