RECONNAISSANCE MAPPING FROM TRIMETROGON AIR PHOTOGRAPHS IN THE ANGLO-EGYPTIAN SUDAN

Abstract

Trimetrogon air surveys have been used extensively in the United States and Canada but seem to have had less favour on this side of the Atlantic in spite of the fact that large areas over here were photographed in this way during the last war. The Sudan is a very large country, but not a rich one; and up to the present it has not been able to undertake its own aerial photography. The gift of a very large number of American trimetrogon photographs covering half the country was therefore very welcome, and it seemed worth our while to see what could be done with them in spite of the known disadvantages of this type of photography for anything but small scale mapping. The methods of planimetric mapping from these photographs developed in the United States were expressly designed to be as simple as possible and to be capable of division into a number of easy tasks which could be performed by any educated person after a short course of training. Nevertheless we felt that they could be simplified a great deal more if the problem was approached from a different angle, particularly in view of the very high standard of flying which was apparent in the photographs covering the Sudan.     

A PROJECTION METHOD OF MAPPING FROM AIR PHOTOGRAPHS

Abstract

An instrument was previously described in the Transactions of the Royal Society of S. Africa for the setting of pairs of photographs, taken from air stations, in correspondence; that is, in the same relative positions that the camera occupied in space at the moments of exposure. The principle of the instrument may be recalled.     

COMPARATIVE ANALYSIS OF FEATURES ON RADAR IMAGERY AND AERIAL PHOTOGRAPHS IN DESERT AND MOUNTAINOUS LANDSCAPES

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.     

MAPPING THE AVALANCHE HAZARD FOR MOUNTAINOUS AREAS OF AFGHANISTAN

The authors describe a procedure for the compilation of maps of the avalanche hazard in high-mountain regions of Afghanistan. The basic sources of information include space imagery (photographs and scanner imagery), weather station data, and other geographic information on relief, elevation, location of moisture sources, etc. The methodology features the compilation of series of increasingly more specific and informative maps and graphs regarding the avalanche hazard: terrain types, snow cover depth and seasonal extent, duration of snow cover and its elevational zonation, snow as a factor in avalanche formation, and summary map of avalanche hazard. Translated by Elliott B. Urdang, Providence, RI 02906 from: Materialy glyatsiologicheskikh issledovaniy, 1991, No. 71, pp. 86–93.     

THE APPLICATION OF TRANSFORMATION FACTORS TO THE ADJUSTMENT OF AIR PHOTOGRAPHS COVERING NARROW LAND AREAS AND COASTLINES

Abstract

1. This new method of adjusting air photographs numerically to a uniform scale on a final map grid has already been described by the writert, where it concerns a large block-adjustment. The method to be described in this paper is the application of the same principle to the adjustment of photographic strips, covering narrow land areas and coastlines.     

STUDY OF THE MORPHOSTRUCTURES OF MOUNTAINOUS AREAS FROM SPACE IMAGERY

The authors review recent developments in the USSR in the use of remote sensing imagery in the analysis, at the world-regional and local levels, of major relief elements (and structural elements manifest in relief) typical of mountainous country. Keys to their interpretation at a variety of scales are described. Case studies and detailed interpretation of imagery in the Soviet Far East and Central Asia (large-scale) and the Caucasus (intermediate-scale) provide for the identification of all morphostructural elements possible through traditional analysis, and in the latter case, for the first direct detection of transverse (cross-cutting) faults. Translated from: Geomorfologiya, 1988, No. 1, pp. 16-29.     

THE INTERRELATIONSHIP AND DYNAMICS OF VEGETATION COVER AND WATER IN THE NORTH CASPIAN REGION

The effectiveness of utilizing the remote sensing signatures of various vegetation associations along the Volga delta region as indicators of specific water availability/flooding conditions is explored. Considerable attention first is devoted to elucidating relationships between higher aquatic vegetation and hydraulic regimes on the basis of field and laboratory studies, before the focus shifts to how remote sensing imagery can provide insights into these relationships. An output of the process was a series of maps depicting environmental change and suggesting sites where reclamation and public health measures were necessary. Translated from: L. N. Vasil'yev, ed., Kosmicheskiye metody izucheniya biosfery [Remote Sensing Methods in the Study of the Biosphere]. Moscow: Nauka, 1990, pp. 88–93.     

AIR SURVEY: THE RAND METHOD OF HEIGHTING FROM NEAR VERTICAL PHOTOGRAPHS

Abstract

The method outlined below is a simple and rapid method, requiring no expensive equipment, of obtaining true heights from pairs of near vertical air photographs with a minimum of ground control. It is a direct application of the Fourcade theorem and, as it was finally developed at the University of the Witwatersrand in 1948-49, it has been given the name “Rand method” in the hope that this will connect it with Dr. Fourcade's country.     

THE ERRORS IN A RADIAL LINE PLOT OF AIR PHOTOGRAPHS

Abstract

Lieut.-Col. Browne's interesting method of combii1ing radial line plots (“The Application of Transformation Factors to the Adjustment of Air Photographs”, E.S.R., x, 73, 119-130) depends for its success on the basic accuracy of the radial line plots of the individual air photo strips. It therefore poses the very interesting question: What accuracy can we expect in a graphical radial line plot?     

AIR SURVEY: THE RAND METHOD OF HEIGHTING FROM NEAR VERTICAL PHOTOGRAPHS

Abstract

The simplest approach is that of spherical trigonometry. In the following proof I have departed from Hotine's sign conventions in an attempt to obtain consistency between the spherical quantities and the photo rectangular co-ordinates.     

AN EXPERIMENT IN MAPPING THE DISTRIBUTION OF THE STEPPE MARMOT USING AERIAL PHOTOGRAPHS

A method for mapping the distribution of a common steppe mammal, the steppe marmot, is described, based on the interpretation of air photos of its life activities (i.e., burrows). Air photos at 1:30,000 scale are used in the compilation of a map of the density of marmot burrows, which permits close and more efficient investigation of the spatial correspondence of marmot habitats and natural conditions and facilitates the selection of routes and areas of sampling in advance of marmot population counts. Translated by Kurt E. Engelmann, Seattle, WA 98195 from: Vestnik Moskovskogo Universiteta, geografiya, 1989, No. 3, pp. 94–99.     

北京山区植被覆被率遥感制图与景观格局分析——以门头沟区为例

准确、快速地获取植被覆盖状况信息是北山区生态恢复和建设的关键与重点.本文在FCD Mapping model的原理和方法基础上,利用TM图像对北京门头沟区植被覆被率展开调查和制图应用研究,并利用FRAGSTATS软件对所得的植被覆盖等级图从斑块大小、斑块数、斑块密度、斑块平均面积、分形维数和聚集度等角度进行了空间格局的剖析.     

THE MAPPING AND STUDY OF THE ISSYK-KUL' SHORELINE WITH AIR PHOTOS

Efforts to monitor and map the changing water level and shoreline of a large mountain lake in Central Asia with aerial photographs are described. The essence of the work involved the mapping of the shoreline and position of river deltas from air photos from various years during the period 1949-1980, at uniform scale and at a level of accuracy permitting the quantitative (cartometric) as well as qualitative assessment of change. The sequence of work in compilation of map-diagrams for different parts of the shoreline involved the preliminary referencing of photos to a map, photo interpretation and compilation of large-scale “graphic diagrams,” preparation of a cartographic base, reduction and placement of diagrams on the base, and transformation of the image as a whole. Results of analysis of these map-diagrams are summarized. Translated from: Vestnik Leningradskogo Universiteta, ser. 7: geologiya, geografiya, 1986, No. 2, pp. 44-48.     

数字地图制图数学基础的自动建立与图廓整饰

分析了建立地形图数学基础的基本原理及过程,采用Gauss-Kruger投影自动计算其数学要素,按照地形图图式规范,以模块化结构方式实现了数字地图数学基础的自动建立与图廓整饰。     

ESTIMATION OF PRECIPITATION FROM CLOUD-COVER PHOTOGRAPHS OF THE METEOR SATELLITES IN THE NONCHERNOZEM REGION

The authors propose a technique for reconstructing precipitation sums for particular areas on the basis of satellite cloud photography. The method is illustrated with reference to six 5-degree squares in the Nonchernozem Region of the USSR for the month of July during the period 1971-80. Good agreement is found not only between the reconstructed precipitation sums and the actual precipitation during the study period, but also between the mean of the reconstructed July precipitation during the 10-year period and the actual long-term mean precipitation for that month. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1983, No. 5, pp. 82-87.     

THE POTENTIAL FOR VISUAL AND AUTOMATED INTERPRETATION OF FOREST VEGETATION WITH SCANNER IMAGERY

Feature classification maps derived from visual and automated methods of interpreting band-specific and composite imagery from the “Fragment” multispectral scanning system are compared in the study of vegetation and related features along the Gulf of Riga. The automated method, featuring a two-stage unsupervised/supervised classification algorithm developed at Moscow University (see MSRS, 1984, No. 3, pp. 255-261) provided for enhanced discrimination of wetland areas, farm land, and settlements, as well as for the elimination of extraneous components (especially the above) visually classified as deciduous forest. Translated from: Vestnilk Moskovskogo Universiteta, geografiya, 1988, No. 3, pp. 49-57 by Jay K. Mitchell, PlanEcon, Inc., Washington, DC 20005.