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1.
Aerial photographic surveys of the White Sea have proven to be an effective means for studying the character of bottom relief and bottom sediments in shallow areas along its coast, particularly when film sensitive to visible radiation in the yellow-green range of the spectrum is used. More specifically, the article discusses methods of aerial photographic surveying, keys for the interpretation of different types of bottom sediments, methods of mapping underwater vegetation from air photos, and the potential of radar imagery for the indirect interpretation of bottom features. Sample interpretation maps from the White Sea are included. Translated by Edward Torrey, Alexandria, VA 22308 from Izvestiya Vsesoyuznogo Geograficheskogo Obshchestva, 1988, No. 4, pp. 314-321.  相似文献   

2.
The findings of a program monitoring the growth of an enormous man-made lake, created by the flooding of a low-lying area by irrigation water drainage, are described. Black-and-white space images for the period 1973-1985 are used to determine rates of shoreline displacement, map the growth in the lake's water area, and to determine probable areas of future flooding as a basis for prediction of future lake levels and shoreline positions. Translated from: Geodeziya i kartografiya, 1988, No. 7, pp. 44-46.  相似文献   

3.
A Russian-American team of remote sensing researchers investigates the applications of active microwave (synthetic-aperture radar) imagery for estimation of water reserves in snowpack in the Western Sayan Range of East Siberia. Considerable attention is devoted to an explanation of the study's principal finding—that a fundamentally different statistical relationship exists between strength of the reflected radar signal and snow cover depth in open areas versus forested areas with high levels of canopy closure. Translated by Edward Torrey, Alexandria, VA from: Geografiya i prirodnyye resursy, 1999, No. 4, pp. 85-90.  相似文献   

4.
5.
Space images afford a relatively new, rapid, and more economical source of information for the accurate mapping of exogenous factors of relief formation, particularly in areas of highly complex topography. This is illustrated in the mapping of such features along the route of the Baykal-Amur Railroad. Translated by Edward Torrey, Alexandria, VA 22308 from: Geografiya i prirodnyye resursy, 1988, No. 4, pp. 107-112.  相似文献   

6.
The relative information yield of radar imagery and aerial photographs is compared for selected natural and cultural features (mountains, erosional depressions, low and high forest, desert plants and shrubs, reeds, and canals) in a number of desert and mountainous areas. The types of aerial photographic and radar equipment used are discussed and recommendations are made regarding when preference should be given to one or the other type of system. Translated by Edward Torrey, Alexandria, VA 22308 from: Vestnik Leningradskogo Universiteta, seriya 7 (geologiya, geografiya), 1989, No. 2, pp. 106–110.  相似文献   

7.
An analysis is made of conditions believed to be optimum for a stereoscopic survey of the Earth's surface by a synthetic-aperture radar on board a spacecraft. Variants for construction of an orbiting stereosystem and factors contributing to a radiometric mismatch of stereopair images are examined. Analysis and choice of optimum conditions for a stereophotogrammetric survey are oriented toward facilitating the computer processing of radar images for the purpose of obtaining digital terrain models.  相似文献   

8.
The paper presents a series of guidelines, developed by the “Aerogeologiya” prospecting trust, for the use of remote sensing imagery in the study of oil-gas potential in remote areas of the USSR. These guidelines take into consideration both conventional oil-gas exploration strategies and the sequence typical of remote sensing research [from small-scale, general analysis, to large-scale detailed studies]. At present predominantly small-scale imagery is used for general reconnaissance, although instances where larger-scale images provide the basis for more specific investigations are also mentioned. A diagram demonstrates how remote sensing might be incorporated into the traditional framework of oil-gas exploration. Translated from: Kompleksnyye aerokosmicheskiye issledovaniya Sibiri, A. L. Yanshin and L. K. Zyat'kova, eds. Novosibirsk: Nauka, 1984, pp. 33-40.  相似文献   

9.
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   

10.
The author outlines, in diagrammatic form, a procedure for the joint use of old maps (topographic, land survey, etc.) and current space imagery to compile maps of environmental change. The ancient maps reveal land use and physical conditions which serve as a benchmark for evaluation of subsequent change. Space imagery is useful both in updating the current state of the environment and providing a cartographic base for the preparation of final maps. Selected areas of Moscow Oblast are used as test sites. Translated from: Izvestiya vuzov, Geodeziya i aerofotos' yem-ka, 1985, No. 1, pp. 104-109.  相似文献   

11.
Optical remote sensing data have been extensively used to derive biophysical properties that relate forest type and composition. However, stand density, stand height and stand volume cannot be estimated directly from optical remote sensing data owing to poor sensitivity between these parameters and spectral reflectance. The ability of microwave energy to penetrate within forest vegetation makes it possible to extract information on both the crown and trunk components from radar data. The type of polarization employed determines the radar response to the various shapes and orientations of the scattering mechanisms within the canopy or trunk. This study mainly presents experimental results obtained with airborne E-SAR using polarimetric C and L bands over the tropical dry deciduous forest of Chandrapur Forest Division, Maharashtra. A detailed documentation of the relationship between SAR C & L bands backscattering and forest stand variables has been provided in the present study through linear correlation. Linear correlation of the single channel SAR derived estimates with the field measured means show a good correlation between L HV backscattering coefficient with stand volume (r2 = 0.71) and L HH backscattering coefficient with stand density (r2 = 0.75). The results imply that SAR data has significant potential for stand menstruation in operational forestry.  相似文献   

12.
General principles are outlined for the use of a series of remote sensing images (obtained for the same area of the earth's surface for different points in time) in the detection of significant changes in land use and environmental conditions. Emphasis is placed on visual methods of interpretation, and a number of different methods for graphically analyzing the dynamics of earth surface features on photographic image products are described. A final section describes procedures for cartographically representing the dynamics of features interpreted from multitemporal images. Translated by Jay Mitchell; PlanEcon, Inc.; Washington, DC 20005 from: Vestnik Moskovskogo Universiteta, geografiya, 1987, No. 6, pp. 57-60.  相似文献   

13.
SAR影像中叠掩与阴影区域的识别 ——以湖北巴东为例   总被引:2,自引:0,他引:2  
SAR影像中叠掩和阴影区域的识别是滑坡监测中的首要工作,本文针对这一工作利用雷达卫星成像时的几何模型与图像处理中形态学方法综合识别叠掩与阴影区域,以ALOS-2数据为例,对比该地区雷达强度图像,验证了本文试验方法的可靠性。  相似文献   

14.
Side-looking airborne radar systems (SLAR), which produce fair quality images of the earth’s surface, have been developed over the past twenty years. These systems provide synoptic information over large areas with great speed. In regions where constant cloud cover prevents or hampers aerial photography, radar can be a source of valuable information: however, in less adverse weather conditions and at larger scales single radar images, until quite recently the normal presentation, cannot compete with conventional, stereoscopically viewed aerial photographs. It has now become common practice to take parallel strips with a large, 30–60%, overlap and scanned from the same direction. In this way a stereoscopic effect may be obtained, which considerably improves the interpretation possibilities of such radar images. The same analytical techniques used in photo-geology can also be applied to radar-interpretation. In order to obtain optimal results, the geologist who interprets radar images should have some understanding of radar operation.  相似文献   

15.
Waterline detection in the intertidal areas was investigated through synthetic aperture radar (SAR) images and field measurements. Two valuable facts were found in this letter: 1) A discrepancy of waterlines between L- and P-band airborne SAR images was discovered and investigated through precise global positioning system measurements and the theory of the SAR imaging mechanism. In the intertidal areas having low slopes, the Bragg waves resonant with the radar signal can reside in different depths depending on the radar frequency, with the result that the boundary between water and land can be mapped differently in the respective SAR images. 2) Intertidal areas covered with a water film present low radar backscatter in SAR images, which can cause mislocation of waterlines  相似文献   

16.
The authors attempt to identify and standardize the cartographic symbols (“images”) used to represent a variety of specific geomorphological features. A large number of cartographic representations of landform features found on geological-geomorphological maps are classified in terms of their basic pattern/configuration and the level of complexity within each major pattern type. It is argued that the pattern or configuration of a cartographic symbol used to represent a geomorphological feature should represent the spatial structure of that feature with sufficient reliability to serve as a key to an understanding of its genesis. Translated from: Geomorfologiya, 1987, No. 2, pp. 62-66.  相似文献   

17.
京西地区多种遥感图像地质解译效果评价   总被引:1,自引:0,他引:1  
笔者以京西王平村地区作为评价区,对多种遥感图像在地质上的解像能力进行了比较和评述。指出了彩红外像片,侧视雷达像片和陆地卫星图像的应用条件,并分析了各种图像在解译中的优势和不足。  相似文献   

18.
时间同步技术是卫星导航定位系统设计的关键技术之一。根据卫星双向共视法时间比对的基本原理,详细推导了该时间同步方法在地心惯性系中精确到卫星和地面站速度的二次幂以及加速度的一次幂的计算模型,并以GEO卫星和GPS卫星为例,分析了该计算模型中的距离改正项时延对地面站间相对钟差的影响量级。结果表明:对于GEO卫星、GPS卫星与地面站之间的比对,当要求 的计算精度时,距离改正项时延只需要考虑到卫星速度项、地面站速度项的影响;当要求 的计算精度时,还需要考虑到卫星速度二次幂项、卫星加速度项、地面站与卫星相对钟差对卫星速度项、地面站间相对钟差对地面站速度项的影响。  相似文献   

19.
Atmospheric boundary-layer stratification exerts a considerable influence on side-looking radar imagery of the sea surface in the centimeter range. Characteristic cellular structures present on the imagery under conditions of instability in the atmospheric boundary layer do not appear on images recorded under stable atmospheric conditions. The possibility of observation of dry and moist convection in the atmospheric layer above the water surface is examined.  相似文献   

20.
马尾松毛虫危害区植被指数时序变化特征研究   总被引:6,自引:1,他引:6  
本文介绍了利用虫害年度的多时相NOAA-AVHRR图像数据计算监测区归一化差植被指数(NDVI),结合收集到的监测区的马尾松毛虫害历史资料来进行森林病虫害监测和预报的研究成果。从统计编制的分区NDVI时间序列变化曲线的对比来看,虫害区与非虫害区NDVI曲线具有一定的时序变化特征,对监测虫害有一定作用,也显示了NOAA-AVHRR资料在森林病虫害监测预报方面有一定应用前景。  相似文献   

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