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1.
《测量评论》2013,45(6):275-284
AbstractWith the modern calculating machine in easy reach of every computer, the problem of determining the position of an occupied point from which direction observations have been made to three or more known points has become quite simple. The method outlined below is quite elegant in form and exceedingly simple on the machine. Let A, B, C be the three points whose co-ordinates (X1Y1), (X2Y2), (X3Y3) are known, and let (XY) be the co-ordinates of the point P which we wish to fix. 相似文献
2.
M. M. Romanovskaya 《地理信息系统科学与遥感》2013,50(4):331-337
General principles underlying the study of spatial inequality are outlined from a Soviet perspective before more specific coverage of guidelines for its portrayal in cartographic form. Questions addressed in the development of a center-periphery model for isarithmic mapping of socioeconomic differences in Hungary include selection of appropriate indices and samplings of data points for mapping, and methods for data normalization and comparison. Examples of both aggregate and more narrowly focused maps of living conditions are included. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1985, No. 4, pp. 68-74. 相似文献
3.
《测量评论》2013,45(78):366-368
AbstractThe method of reducing circummeridian altitudes or zenith distances to the meridian, using the factors m and n as tabulated by Chauvenet, is well known. The following method, which does not use these factars, has been faund both more convenient and more accurate in practice. The formula can be easily obtained by expanding m and n in powers of t, but far the sake af campleteness the derivatian is here given from the beginning. 相似文献
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V. R. Yashchenko 《地理信息系统科学与遥感》2013,50(1):3-8
The Director of the Main Administration of Geodesy and Cartography describes the history and recent developments of a program for topographic coverage of the entire country at 1:25,000 scale. Most noteworthy are the start of surveying at this scale before 1940, its temporary suspension during World War II, and acceleration of the work since the 1950s with the more widespread use of stereophotogrammetric methods. Considerable attention is paid to improvements in aerial photographic, photogrammetric, and geodetic technologies in support of more effective cartographic work. A concluding section describes the properties of the new maps and their applications. Translated by Larry Richardson, Los Angeles, CA 90039 from: Geodeziya i kartografiya, 1989, No. 8, pp. 1–5. 相似文献
5.
S. V. Vasil'yev 《地理信息系统科学与遥感》2013,50(1):77-86
A “genetic” principle for the identification of morphological units on a floodplain landscape is applied to the mapping of vegetation and, more specifically, to a study of the spatial distribution of forest vegetation within the Ob' River floodplain. Aspects of the problem which are discussed include the identification and ranking of floodplain units and their components and appropriate scales for image interpretation and mapping. The principles and procedures outlined are applicable to the mapping of other floodplains. Translated by Edward Torrey, Alexandria, VA 22308 from: Geografiya i prirodnyye resursy, 1989, No. 2, pp. 78–84. 相似文献
6.
AbstractThe original object of a transition curve was to ease the change from a straight line of communication to a circular line, or vice versa. It may even be laid out to connect one circular curve with another of different radius. In this manner the discomfort and even the danger to travellers in vehicles traversing such lines of way are obviated, abrupt variations of acceleration being overcome. The first curve to be used for this purpose was the elastica, introduced by Froude about 1842, and it is worthy of note that in their initial lengths all transition curves conform closely to this earliest form of easement. It is indeed obvious that, since the circle is a curve of the second order, an easing curve must be of a higher order ; the curve of the next higher order is of the third degree, and of all such curves the cubic parabola is the simplest, its equation being a2y ==x3. 相似文献
7.
The authors outline a methodology for the small-scale hypsometric mapping of plains areas based on the averaging of relief—this for the purpose of portraying the most important details of local relief (small erosional landforms) without obscuring larger, major relief forms or compromising the readability of the map. An example map (25-m contour interval) of the Soviet portion of the East European Plain at a scale of 1:5,000,000 is included. The elevations portrayed on this map were averaged, according to a multi-stage procedure, from grid cells on a 1:2,500,000 map before transference onto the smaller-scale map base. The new map makes possible a revised estimate of the average elevation of the Russian Plain and depicts well the effects of both endogenous and exogenous factors on relief formation. Translated from: Geomorfologiya, 1987, No. 1, pp. 22-29. 相似文献
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《测量评论》2013,45(38):480-481
AbstractIn a letter published in a recent issue of Nature, Prof. L. F. Bates and Mr J. C. Wilson, of University College, Nottingham, have described a new and novel method of determining the coefficient of thermal expansion of invar. Although this method is hardly likely to be applied to the measurement of the coefficient of expansion of long invar tapes, such as are used by surveyors, yet it is so novel and ingenious in itself that a short reference to it may not be out of place in this Review. One extremely interesting thing about it is that no measurements of a length, or of changes of length, are involved. 相似文献
10.
《测量评论》2013,45(47):24-29
Abstract1. Theory.—In Figs. 1. a and 1. b the letters R represent in each case four equal links of any length forming a freely jointed rhombus. L, L are two equal links of any length. (n ± 1), n are respectively a fixed and a rotating link whose lengths are in the ratio (n ± 1)/n. 相似文献
11.
Vegetation signatures on aerial photographs and space imagery are used as indicators of soil moisture differences in a Siberian taiga landscape. The authors use remote sensing products to identify all major habitat types resulting from variable soil moisture regimes that were observed on the ground. These types are described, as are their interpretation keys and the effects of scale change on habitat discrimination. Translated from: Kosmicheskiye metody izucheniya prirodnoy sredy Sibiri i Dal'nego Vostoka, Novosibirsk, 1983, pp. 63-74. 相似文献
12.
《测量评论》2013,45(47):30-35
AbstractIn the Empire Survey Review for October 1938 (iv, 30, 480) a simple demonstration of the condition to be satisfied for conformal representation was given. This condition may be expressed by the equation w = f(z), where w and z are complex variables representing corresponding points in the w-plane and z-plane respectively, and f(z) is an analytic function of z. 相似文献
13.
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
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15.
《测量评论》2013,45(85):319-325
AbstractIn a recent issue of this Review, an example is given of the conformal transformation of a network of triangulation using Newton's interpolation formula with divided differences. While the application of the method appears to be new, attention should be drawn to the fact that Kruger employed Lagrange's interpolation formula in a discussion and extension of the Schols method in a paper which was published in the Zeitschrift für Vermessungswesen in 1896. A reference to this paper was given at the end of the paper, “Adjustment of the Secondary Triangulation of South Africa”, published in a previous issue of the E.S.R. (iv, 30, 480). 相似文献
16.
An approach is outlined for the construction of a digital terrain model based on elevations assigned to nodes of an irregular (non-rectangular) grid. More specifically, this grid consists of a series of non-intersecting, non-equilateral triangles whose apices are prominent points of local relief or points located on structure lines, and whose sides represent portions of structure lines or arbitrarily selected line segments. Such an irregular model provides for a better approximation of basic terrain structure than those constructed from traditional, geometrically regular networks. Operation of algorithms for the plotting of contour lines from such a model is described. Translated from: Geodeziya i kartografiya, 1986, No. 2, pp. 34-38. 相似文献
17.
《测量评论》2013,45(62):300-311
AbstractChesterton did not, of course, intend this gibe to be taken literally. But the more we consider what he would doubtless have called the “Higher Geodetics”, the more we must conclude that there is some literal justification for it. Not only are straight lines straight. A sufficiently short part of a curved line may also be considered straight, provided that it is continuous (i.e. does not contain a sudden break or sharp corner), and provided we are not concerned with a measure of its curvature. Similarly a square mile or so on the curved surface of the conventionally spheroidal earth is to all intents and purposes flat. We shall achieve a considerable simplification, without any approximation, in the treatment of the present subject by getting back to these fundamental glimpses of the obvious, whether the formalists and conformalists accept them or not. 相似文献
18.
AbstractFor the sake of the junior reader we may repeat an old and simple investigation. Let us suppose that the paper on which a map is printed undergoes a regular expansion p in one direction, say the X direction, and another regular expansion q in the Y direction, perpendicular to the former; it is required to know the effect of these expansions on the area of any parcel on the map. Note that, so far as the mathematics are affected, X and Y are not necessarily parallel to the margins of the sheet; we shall take them here as axes of any rectangular coordinate system. The symbols p and q are regarded as ratios, so that 100p and 100p represent the percentage expansions; if the paper contracts instead of expanding, no more is necessary than to change the sign. 相似文献
19.
S. A. Shavrov 《地理信息系统科学与遥感》2013,50(2):96-103
A procedure is described for the revision of digital maps in geographic information systems, the basis of which rests upon a “mutual and unambiguous correspondence” between a digital map and its structural (text or graphic) model(s). Rules of transference, editing, elimination, inclusion, and cross-referencing of names are elaborated for regulation of the processes by which non-digital (cartographic, air photo, statistical) sources of new information are used to transform digital information in the original data base. Revision of digital maps is accomplished through creation of a data base of digital corrections to an original data base and/or subsequent editing of digital map(s) from these corrections or others initiated during raster scanning. Translated from: Geodeziya i kartografiya, 1986, No. 9, pp. 38-43. 相似文献
20.
《测量评论》2013,45(24):68-69
AbstractThe following points occurred to me when reading the interesting paper on crustal equilibrium in E.S.R. No. 23. The principle of compensation or isostasy necessarily involves the idea of two different kinds of rock structure—one strong, the other weak or in extreme cases fluid; for example, there is the familiar case of the strong iceberg resisting change of shape in the liquid sea. In dealing with crustal problems of the earth then, we should make up our minds which part is to be considered as strong, e.g. the granite crust, and which part as weak or fluid, e.g. material at a depth x km. (say roo km.); by weak or fluid I mean that a possibility exists of horizontal movement. 相似文献