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241.
The authors discuss a method by which the image characteristics of forest vegetation can be used to determine various valuational characteristics of forest stands through the combination of air photo interpretation and ground surveys at selected training sites. Construction of curves showing changes in image texture and tone occurring at different stages in the growth cycle of a pine forest community are used to estimate the age of a forest stand, and through known relationships between age and other stand characteristics incorporated into yield tables, to approximate such valuational characteristics as mean diameter, mean height, and stand volume. Translated from: Distantsionnyye issledovaniya rel'yefa Sibiri, A. L. Yanshin and V. N. Sharanov, eds. Novosibirsk, Nauka, 1985, pp. 73-78.  相似文献   
242.
A method of complex image processing, i.e., the simultaneous use of various kinds of remote sensing imagery in the mapping and study of geographic features, is outlined. It features the use of computerized techniques (a) to identify shots or frames of auxiliary types of imagery containing the same specific geographic features identified on the principal type of imagery [this through the scanning of code lines containing information about the coordinates of imaging, flight direction and altitude of the plane or sensing platform, etc.], and (b) to precisely locate the features of interest within these shots or frames. Translated from: Izvestiya vysshykh uchebnykh zavededeniy, Geodeziya i aerofotos'yemka, 1986, No. 1, pp. 86–91.  相似文献   
243.
Results of experiments in the measurement of heat flux at the ocean-atmosphere boundary layer are described. More specifically, an algorithm is presented for the calculation of the different components of total heat flux (from the ocean into the atmosphere) based on estimates of water temperature, wind velocity, and cloud cover obtained from remote sensing imagery. Use of the algorithm yields values for total heat flux which, when averaged over a ten-day period, are only 10% less accurate than those obtained according to traditional methods (research vessels, buoys, offshore platforms). Translated from: Izvestiya vysshykh uchebnykh zavedeniy, Geodezlya i aerofotos”yemka, 1986, No. 5, pp. 117-120.  相似文献   
244.
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   
245.
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   
246.
Specific criteria used in the compilation of large-scale maps of erosion-prone areas are defined and evaluated for tracts of land representing a number of different agricultural cover types. Formulas are derived which facilitate the mapping of such areas based on such readily observable morphometric characteristics as slope length and steepness. Translated by Edward Torrey, Alexandria, VA 22308 from: Vestnik Moskovskogo Universiteta, geografiya, 1988, No. 5, pp. 25-31.  相似文献   
247.
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   
248.
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   
249.
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   
250.
Another paper in a series of articles on ecological-geographic mapping (see for example, Mapping Sciences and Remote Sensing, Vol. 31, No. 3, July-September 1994, pp. 185-220) focuses on outlining a concise typology of such maps and providing a brief history of their emergence during the 1970s and 1980s. A subsequent section is devoted to methods and technology used in the compilation of ecological-geographic maps, particularly the multiple variants of data organization, processing, and cartographic representation that can be factored into research design. Translated by Edward Torrey, Alexandria, VA 22308 from: Geografiya i prirodnyye resursy, 1995, No. 4, pp. 10-18.  相似文献   
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