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1.
《测量评论》2013,45(32):66-67
AbstractThe projection in question is a mean between Mercator's and the Equal-Area Cylindrical Projection which is formed by orthographic projection from the sphere upon the circumscribing cylinder. Both projections are computed on the spherical assumption. Mercator's Projection is, of course, the best known of the orthomorphic group; the Equal-Area Cylindrical Projection is the simplest of the equal-area group. Each projection may be said to represent an extreme case; and the mean between them may perhaps, for some purposes, be a useful compromise. 相似文献
2.
《测量评论》2013,45(62):311-314
AbstractIn E.S.R., viii, 56, 70, Brigadier K. M. Papworth has given expressions for the angular corrections, known as (t – t) corrections, in the Lambert NO.2 Projection, derived from empirical considerations based on actual detailed calculations. Apparently some difficulty has been experienced in offering a proof. In view of the widespread use of the Lambert Projection in World War II, it is hoped that the following proof will be found to be of more than academic interest. 相似文献
3.
AbstractI. Introduction.—Map projection is a branch of applied mathematics which owes much to J. H. Lambert (v. this Review, i, 2, 91). In his “Beyträge zum Gebrauche der Mathematik und deren Anwendung” (Berlin, 1772) he arrived at a form of projection whereof the Transverse Mercator is a special case, and pointed out that this special case is adapted to a country of great extent in latitude but of small longitudinal width. Germain (“Traité des Projections”, Paris, 1865) described it as the Projection cylindrique orthomorphe de Lambert, but he also introduced the name Projection de Mercator transverse or renversée; he shows that Lambert's treatment of the projection was remarkably simple. 相似文献
4.
《测量评论》2013,45(56):68-72
AbstractI. The present writer has been trying for the past two years to get reasonably easy expressions for the (t – t) correction and the scale factor in the Lambert NO.2 Projection. He succeeded in obtaining a formula for (t – t) in terms of eastings and northings, but, like the author of the articles on “Grid Bearings and Distances on the Conical Orthomorphic Projection” which were published recently in this Review, he came to the conclusion that any such formula is too unwieldy for ordinary use. He then tried to get an expression for (t – t) in terms of latitude and longitude, and has now obtained one by purely empirical methods which seems to work in practice. No proof of this formula is offered, or is available at present, as this is a matter which the writer is content to leave to others with greater mathematical interests and attainments than he possesses. 相似文献
5.
AbstractIn January 1938 the writer decided against holding up for more years some work on the Transverse Mercator Projection (E.S.R., 27, 275). The extension to the spheroid was not then complete, nor is the present paper to be regarded as a logical continuance. It is first proposed to show the results of “transplanting” orthomorphically upon the spheroid a spherical configuration forming a graticule. 相似文献
6.
《测量评论》2013,45(31):38-50
AbstractOn page 480 of the last number of this Review Capt. E. H. Thompson, R.E., in his paper on “The Condition for the Construction of a Conformal Projection”, deals with a subject which, in the opinion of the present writer, is rather insufficiently explained or dealt with in any text-book on Geodesy or on Map. Projections that he has seen. The explanations or proofs usually given are probably adequate if it can be assumed that the reader has a fairly good knowledge of the properties of functions of the complex variable. 相似文献
7.
《测量评论》2013,45(26):230-234
AbstractTHE resolutions and pious hopes (væux) passed by the International Union of Geodesy and Geophysics at Edinburgh in September 1936 have just been circulated in a formidable document of 8 pages and XXIX commandments. Of these, two affect the Cape-to-Cairo line particularly and they seem to deserve special study. The first of these, Number III—on systems of Projections—applies the meridional strips of the Transverse Mercator Projection apparently to all maps, topographical as well as cadastral. 相似文献
8.
《测量评论》2013,45(21):417-422
AbstractThe Transverse Mercator Projection is also called the Conformal of Gauss since it was devised by him in the early part of the nineteenth century in connexion with the Triangulation of Hanover. It belongs to the class of cylindrical orthomorphic projections. That is to say, the Earth's surface, or part thereof, is developed on the surface of a cylinder, and there is practically no angular distortion, an angle on the surface of the Earth being represented on the map by almost precisely the same angle. The representation of meridians and parallels, for instance, shows them intersecting at right angles as they actually do on the Earth's surface; but this orthotomic condition, though essential, is not in itself sufficient for orthomorphism. 相似文献
9.
《测量评论》2013,45(58):142-152
AbstractIn January 1940, in a paper entitled “The Transverse Mercator Projection: A Critical Examination” (E.S.R., v, 35, 285), the late Captain G. T. McCaw obtained expressions for the co-ordinates of a point on the Transverse Mercator projection of the spheroid which appeared to cast suspicion on the results originally derived by Gauss. McCaw considered, in fact, that his expressions gave the true measures of the co-ordinates, and that the Gauss method contained some invalidity. He requested readers to report any flaw that might be discovered in his work, but apparently no such flaw had been detected at the time of his death. It can be shown, however, that the invalidities are in McCaw's methods, and there seems no reason for doubting the results derived by the Gauss method. 相似文献
10.
《The Cartographic journal》2013,50(2):121-126
AbstractIn order to display, predict and combat atmospheric pollution, suitable graphics should be employed. The author proposes some new methods of representation such as mapping air pollution on an air photograph which is printed through screens proportional to air purity, or using the Polyfocal Projection for mapping airport noise. Polar diagrams are used to depict atmospheric stability states. 相似文献
11.
12.
《测量评论》2013,45(69):318-322
AbstractThe Transverse Mercator Projection, now in use for the new O.S. triangulation and mapping of Great Britain, has been the subject of several recent articles in the “Empire Surpey Review. The formulae of the projection itself have been given by various writers, from Gauss, Schreiber and Jordan to Hristow, Tardi, Lee, Hotine and others—not, it is to be regretted, with complete agreement, in all cases. For the purpose for which these formulae have hitherto been employed, in zones of restricted width and in relatively low latitudes, the completeness with which they were given was adequate, and the omission of certain smaller terms, in the fourth and higher powers of the eccentricity, was of no practical importance. In the case of the British grid, however, we have to cover a zone which must be considered as having a total width of some ten to twelve degrees of longitude at least, and extending to latitude 61 °north. This means, firstly, that terms which have as their initial co-efficients the fourth and sixth powers of the longitude ω (or of y) will be of greater magnitude than usual, and secondly that tan2 ? and tan4 ? are likewise greatly increased. Lastly, an inspection of the formulae (as hitherto available) shows a definite tendency for the numerical co-efficients of terms to increase as the terms themselves decrease—e.g. terms in η4, η6, etc. 相似文献
13.
《测量评论》2013,45(10):226-238
AbstractThe Stereographic Projection, owing to the ease and accuracy with which it can be drawn on a small scale, offers natural attractiveness for the treatment of spherical geometry upon a plane surface. It would therefore be rash for a present-day writer to claim as novel what may well be an infringement of patent rights morally belonging to Hipparchus, who possibly knew most of what is worth knowing about the matter 2,000 years ago. However, since a fairly extensive delving into writings upon the subject has not brought to light anything quite on the lines here put forward, it may be worth while to systematize in this paper some processes which the present writer has found practically useful for some time past. 相似文献
14.
《测量评论》2013,45(34):226-228
AbstractGenerally speaking there is a tendency for observations to be judeged by the magnitudes of the triangular errors, although the misclosures of the side equations are equally important. This note explains how to formulate a compehensive criterion covering the two types of misclosure and given in terms of the mean traingular ? m for which definite limits are usually laid down. 相似文献
15.
AbstractA super-resolution enhancement algorithm was proposed based on the combination of fractional calculus and Projection onto Convex Sets (POCS) for unmanned aerial vehicles (UAVs) images. The representative problems of UAV images including motion blur, fisheye effect distortion, overexposed, and so on can be improved by the proposed algorithm. The fractional calculus operator is used to enhance the high-resolution and low-resolution reference frames for POCS. The affine transformation parameters between low-resolution images and reference frame are calculated by Scale Invariant Feature Transform (SIFT) for matching. The point spread function of POCS is simulated by a fractional integral filter instead of Gaussian filter for more clarity of texture and detail. The objective indices and subjective effect are compared between the proposed and other methods. The experimental results indicate that the proposed method outperforms other algorithms in most cases, especially in the structure and detail clarity of the reconstructed images. 相似文献
16.
《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
17.
Summary Within potential theory of Poisson-Laplace equation the boundary value problem of physical geodesy is classified asfree andnonlinear. For solving this typical nonlinear boundary value problem four different types of nonlinear integral equations corresponding
to singular density distributions within single and double layer are presented. The characteristic problem of free boundaries,
theproblem of free surface integrals, is exactly solved bymetric continuation. Even in thelinear approximation of fundamental relations of physical geodesy the basic integral equations becomenonlinear because of the special features of free surface integrals. 相似文献
18.
AbstractGeological mapping is one of the primary tasks of remote sensing. Remote sensing applications are especially useful when extreme environmental conditions inhibit direct survey such as in Antarctica. In this investigation, a satellite-based remote sensing approach was used for mapping alteration mineral zones and lithological units using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data in the Oscar II coast area, north-eastern Graham Land, Antarctic Peninsula. Specialized band ratios and band combinations were developed using visible and near infrared, shortwave infrared (SWIR) and thermal infrared spectral bands of ASTER for detecting alteration mineral assemblages and lithological units in Antarctic environments. Constrained Energy Minimization, Orthogonal Subspace Projection and Adaptive Coherence Estimator algorithms were tested to ASTER SWIR bands for detecting sub-pixels’ abundance of spectral features related to muscovite, kaolinite, illite, montmorillonite, epidote, chlorite and biotite. Results indicate valuable applicability of ASTER data for Antarctic geological mapping. 相似文献
19.
S. H. Laurila 《Journal of Geodesy》1969,43(2):139-153
The main environmental problem in tracking a satellite through the atmosphere is in finding the most probable value of the
mean refractive index. In this paper, the mean refractive index is computed as a four-part model. The troposphere is treated
as one altitude range from sea level to 9 kilometers, and the stratosphere is divided into three altitude ranges, 9 to 18,
18 to 27, and 27 to 36 kilometers. At 36 kilometers, the N-value is approximately equal to two and reduces rapidly to zero.
By the use of theEssen formula in radio wave application and the modifiedKohlrausch formula in light wave application, point-to-point values of the refractive index are computed through these altitude ranges.
The polynomial expansion of second order from the basic exponential function is selected as the model, and the curve-fitting
adjustments of the computed values are established separately to each altitude range to obtain coefficients A, B, and C.
A model based on the U. S. Standard Atmosphere, 1962, is used as the reference to which four sets of actual soundings made
in Lihue, Hawaii and Fairbanks, Alaska on February 3 and July 2, 1966, are compared. The results show that the parabolic adjustment
has a very high reliability. In the use of standard atmosphere, the standard error of the refractive index through the total
altitude range of 0 to 36 kilometers, and at the 70° zenith distance, equal only ±7 millimeters when radio waves are utilized,
and ±3 millimeters when light waves are utilized.
Paper presented at Conference on Refraction Effects in Geodesy and Electronic Distance Measurement, University of New South
Wales, 5–8 November 1968. Hawaii Institute of Geophysics Contribution No. 239. 相似文献
20.
AbstractRiver basin assessment is crucial for water management and to address the watershed issues. So, an integrated river basin management and assessment model using morphometric assessment, remote sensing, GIS and SWAT model was envisaged and applied to Kaddam river basin, Telangana state, India. Morphometric results showed high drainage density ranging from 2.19 to 5.5?km2/km, with elongated fan shape having elongation ratio of 0.60–0.75 with sparse vegetation and high relief. Land use change assessment showed that 265.26?km2 of forest land is converted into irrigated land and has increased sediment yields in watersheds. The calibration (r 2?=?0.74, NSE?=?0.84) and validation (r 2?=?0.72, NSE?=?0.84) of SWAT model showed that simulated and observed results were in agreement and in recommended ranges. The SWAT simulations were used to compute mean annual water and sediment yield from 1997 to 2012, along with morphometric results to categorize critical watersheds and conservation structures were proposed accordingly. 相似文献