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991.
The authors describe the principles and method used in compiling a map of game animal resources for the Midlands region, the name given to the middle segment of the Soviet Union comprising West Siberia, Kazakhstan and Central Asia. The results make it possible to recommend the optimal use of game resources and to identify future prospects of the trapping and hunting economy. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1982, No. 5, pp. 17-23.  相似文献   
992.
The authors present the results of experiments in the use of remote sensing imagery for construction of maps depicting human modification of nature. Four diverse areas within the USSR were selected as mapping sites, providing a broad range of environmental and land-use characteristics for investigation. Human impacts were most effectively mapped for two desert sites. The authors recommend combining satellite imagery with terrestrial spectrometric observations or color-infrared photography in investigations of environmental change in steppeland and forested territory. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1984, No. 6, pp. 11-18.  相似文献   
993.
Algorithms, designed for digital image processing in standard mainframe computers and representing sequential stages in a land-use classification procedure, are used to produce maps of agricultural crop types from multispectral satellite imagery. Pixel reflectance values are first grouped according to an unsupervised “rapid classification algorithm,” or data compression procedure. Mean reflectance values of the resulting classes then go into a supervised “sequential clustering algorithm” where classes are refined according to training value and other parameter inputs. The objective is to increase the accessibility of automated image interpretation while balancing classification accuracy and processing time. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1984, No. 4, pp. 63-69.  相似文献   
994.
The mathematical basis for a feature classification algorithm is described which combines elements of game theory with Bayesian and suboptimal [feature classification] decision rules. Comparison of reflectance values with training area parameters, according to a sequence of diminishing a priori probabilities that the values will be assigned to that particular class results in reductions in computer time during classification. Results of the procedure are demonstrated through a pair of “before” and “after” images. Translated from: Metody kompleksnykh aerokosmicheskikh issledovaniy Sibiri, L. K. Zyat'kova, ed. Novosibirsk: Nauka, 1985, pp. 75–79.  相似文献   
995.
The authors propose a series of general methodological guidelines for animal habitat mapping. These include the use of “summary” indicators (of aggregate effects of environmental conditions on animal populations) as indices for mapping, the combination of laboratory and field work at all but the smallest scales of mapping, and explicit recognition (based on extensive studies of ecological characteristics and life cycles of species being mapped) that habitat boundaries in many cases vary dramatically from vegetation and landscape-geological boundaries. Habitat maps of two study areas are compared with vegetation and landscape maps at identical scales to demonstrate these differences. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1985, No. 3, pp. 95-101.  相似文献   
996.
The author outlines general principles and methods of predictive or forecast mapping in the USSR, more specifically the use of maps in support of geographic forecasting, i.e., prediction of relationships involved in matter, energy, and other flows of ecosystem components. Maps are employed in all stages of geographic forecasting, particularly to identify spatial patterns which can be extrapolated in space or time and used to predict distributions that are difficult or impossible to determine directly, as well as to graphically portray these expected distributions. A scheme for classifying forecast maps in terms of their orientation in time and space is presented. Translated from: Prognoznoye blogeograficheskoye kartografirovaniye: regional'nyy aspekt, Moscow: Nauka, 1985, pp. 6-24.  相似文献   
997.
The author surveys the use of remote sensing imagery in the study of mass exchange in glaciers, i.e., glacier dynamics resulting from phase changes in the water which they contain. A program of research now underway at the Institute of Geography (USSR Academy of Sciences) in conjunction with the “Priroda” Remote Sensing Center (Moscow) focuses on improving methods of data collection and mapping of glacier dynamics from space imagery, and particularly on identifying natural glacioclimatic zones believed to represent specific mass exchange conditions or regimes. The boundary of glacier nourishment separating areas of accumulation and ablation represents a key glacioclimatic indicator of mass exchange on satellite imagery and aerial photography. Translated from: Geodeziya i kartografiya, 1986, No. 5, pp. 26–31.  相似文献   
998.
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   
999.
Principles are outlined for the use of sub-satellite soil, air, water, and vegetation samples as an auxiliary source of information in remote sensing studies of vegetation stress caused by air pollution. More specifically, procedures for satellite-synchronous aerial overflights, vegetation transects, water quality measurements, and soil tests are described as a basis for delineating boundaries between areas of vegetation stress and unpolluted areas in an industrialized area in the central Urals. Translated from: Kosmicheskiy monitoring biosfery, Yu. A. Izrael', V. V. Bugrovskiy, and Yu. V. Novikov, eds. Leningrad: Gidrometeoizdat, 1985, pp. 93-99.  相似文献   
1000.
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   
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