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1.
The authors, drawing upon the work of Hagerstrand and others in the field of spatial diffusion modeling, develop a model for predictive mapping of the spread of disease based on the Monte Carlo method. Analysis of this particular model showed high coefficients of correlation between mathematical probability estimates of times of origin for epidemics in particular territorial units and their densities of population and population potentials. Translated from: Izvestiya, Vsesoyuznogo Geograficheskogo Obshchestva, 1986, No. 1, pp. 67-74.  相似文献   

2.
The author, noting the high cost and complexity of automated methods of processing imagery of the earth's cloud cover, presents a less sophisticated, instrument-aided method yielding similar results. A procedure for analyzing cloud cover patterns based on color synthesis of two-band scanner imagery from Soviet “Meteor” and American NOAA-series weather satellites using a synthesizing projector is outlined. This method adds the interpretation key of color to those of cloud structure and form in the analysis of cloud patterns, enhances cloud-underlying surface contrasts, and compares favorably with more highly automated methods in image preparation and interpretation time. Translated by Jay Mitchell; PlanEcon, Inc.; Washington, DC 20005 from: Izvestiya vysshykh uchebnykh zavedeniy, Geodeziya i aerofotos'yemka, 1987, No. 5, pp. 95-98.  相似文献   

3.
Shortcomings in the representation of bottom relief features on topographic maps of the continental shelves are examined, with particular attention given to submarine ridges and related features, the symbolization of which on such maps has been entirely ineffective. Specific recommendations are given on the form and color of symbols which can be used in upgrading the graphic impact of maps depicting such relief forms. Translated by Edward Torrey, Alexandria, VA 22308 from: Geodeziya i kartografiya, 1989, No. 1, pp. 35–40.  相似文献   

4.
ABSTRACT

The spatial distance (gap) between map symbols can have a great impact on their discriminability, however, there is little empirical evidence to establish spatial and attribute thresholds. In this paper, we examine the effect of the spatial gap in discriminability of color hue and value, that is, we conducted an online study to obtain performance metrics; then an eye-tracking study to understand participants’ strategies and cognitive processes. Participants completed two experimental tasks (compare two areas and decide if their color is the same; and compare three areas and rank them from the lightest to the darkest). The color distances and the spatial distances were strictly controlled for the compared areas. Our analyses confirmed that, overall, increasing the gap between colors has a consistent negative impact on the ability to differentiate them with both sequential and qualitative schemes. Furthermore, we observed that sequential schemes require larger color distances than qualitative schemes for discriminability. Finally, our results suggested that for qualitative colors, the largest tested color distance ?E00 = 10 yields considerably higher levels of accuracy in color discrimination (even when the spatial gap between the two colors is large), thus we recommend ?E00 = 10 to practicing cartographers and other information visualization designers.  相似文献   

5.
An experiment is described in which multiscalar remote sensing imagery is sequentially employed in the detection of various rankings of soil types endemic to the taiga natural zone in the northern USSR. Relief features, vegetation associations, extent of surface water, and drainage patterns visible on imagery at scales from 1:12,000,000 to 1:5,000, also examined at low altitude and in the field at a series of test sites, served as indicators of various soil cover types. Considerable attention is given to an explanation of why these features can be considered valid indicators of taiga soil types as well as to the appearance of the indicators on band-specific (black-and-white) and color composite imagery. Translated from: Izvestiya Akademii Nauk SSSR, seriya geograficheskaya, 1987, No. 3, pp. 87-99.  相似文献   

6.
The authors address a range of issues connected with the visual representation and interpretation of statistical data on maps. Attention is focused on common behaviors of map users in determinations of various characteristics of map symbols. Results are reported from experiments testing the relationship between the accuracy of obtaining quantitative information on a map with the total number of symbols and number of scale levels [size classes] employed, the use (or non-use) of color in the symbolization scheme, etc. Translated by Larry Richardson, Los Angeles, CA 90039 from: Izvestiya Vsesoyuznogo Geograficheskogo Obshchestva, 1989, No. 4, pp. 345–351.  相似文献   

7.
《测量评论》2013,45(88):71-77
Abstract

Some difficulties in interpreting the specifications of instrumental accuracy are pointed out and traced to inadequate information. The paper discusses the possibility of amplifying this information for the benefit of the user and without over-burdening the inspection departments of the manufacturers.

It is suggested that the given information should include (1) estimates of all suspected errors and distortions, (2) the confidence limits relevant to (a) the errors incurred in any given measurements and (b) their point-to-point variation.

Confidencelimits for the effects of observational errors may be worked out from the t-distribution in the usual way, or more readily read from graphs given in this paper. Further research is however needed to investigate the statistical behaviour of other sources of variation in order to establish appropriate systems for the construction of corresponding confidence limits.  相似文献   

8.
《测量评论》2013,45(34):226-228
Abstract

Generally 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   

9.
World Geodetic Datum 2000   总被引：7，自引：1，他引：6  
 Based on the current best estimates of fundamental geodetic parameters {W 0,GM,J 2,Ω} the form parameters of a Somigliana-Pizzetti level ellipsoid, namely the semi-major axis a and semi-minor axis b (or equivalently the linear eccentricity ) are computed and proposed as a new World Geodetic Datum 2000. There are six parameters namely the four fundamental geodetic parameters {W 0,GM,J 2,Ω} and the two form parameters {a,b} or {a,ɛ}, which determine the ellipsoidal reference gravity field of Somigliana-Pizzetti type constraint to two nonlinear condition equations. Their iterative solution leads to best estimates a=(6 378 136.572±0.053)m, b=(6 356 751.920 ± 0.052)m, ɛ=(521 853.580±0.013)m for the tide-free geoide of reference and a=(6 378 136.602±0.053)m, b=(6 356 751.860±0.052)m, ɛ=(521 854.674 ± 0.015)m for the zero-frequency tide geoid of reference. The best estimates of the form parameters of a Somigliana-Pizzetti level ellipsoid, {a,b}, differ significantly by −0.39 m, −0.454 m, respectively, from the data of the Geodetic Reference System 1980. Received: 1 February 1999 / Accepted: 31 August 1999  相似文献   

10.
《测量评论》2013,45(10):206-221
Abstract

4.3. Having found s we may proceed to obtain the coordinates of the air station. This is the vertex of a pyramid, the base edges being of lengths a, b, c and the opposite edges measuring u, v, w respectively. Let h be the distance of the vertex from the plane of the base, and suppose d, e1 e2, e3 are respectively twice the areas of the base and of the oblique faces in order.  相似文献   

11.
The author continues development of his concept of cartography as the “language of the map,” an earlier paper of this subject appearing in translation in M.S.R.S., 1985, No. 1. Although the term language has been widely used to describe cartographic communication, current theory fails to incorporate aspects of the language which provide for a comprehensive understanding of its structure and function. In particular, the language of the map and its symbolic elements cannot be explained reflexively by methods and rules of symbol and map design, since these elements were developed not before but after the existence of the language. The language of the map thus is proposed as the mechanism which provides for replicability or duplication in the way a system of mapmaking-map use functions (under diverse conditions, purposes, historical periods, and levels of training of users) through its different methods, models, and norms. Translated from: Geografiya i prirodnyye resursy, 1985, No. 3, pp. 142-151.  相似文献   

12.
《测量评论》2013,45(62):300-311
Abstract

Chesterton 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   

13.
The method presented here assumes that a single observation can be identified with one of q functional models that compete with one another. The estimation method is based on the assumption that a theoretical quantity, called elementary split potential, can be assigned to each observation. Such quantity is referred to the theory of probability as well as to the theory of information. Parameters of the competitive functional models are estimated by maximizing the split potential globally over for the whole observation set. Additionally, such M split(q) estimates minimize the amount of information that could be provided by other estimates computed for the same observation set. The method is a certain kind of extension of the maximum likelihood method and if one considers the generalizations presented in the paper it can also be regarded as the development of M-estimation. Special attention is paid to the squared M split(q) estimation where the objective function is a squared one. If q = 1, then the squared M split(q) estimation is equivalent to the least squares method. The last part of the paper presents some numerical examples illustrating the properties of the squared M split(q) estimation as well as pointing at possible applications in geodesy and surveying.  相似文献   

14.
The development of a new instructional aid in geography in the USSR is described–an exhibit featuring wall-map sized space imagery of major natural regions. Each station in the exhibit (prepared jointly by the Moscow University Laboratory of Remote Sensing Methods and the Main Administration of Geodesy and Cartography) includes a color image of a site representing one of seven major natural zones, a series of thematic maps based on results of image interpretation, a map showing the location of the imaged area within the USSR, and a series of ground photographs of typical landscapes and land uses. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1988, No. 2, pp. 36-41 by Natalia B. Barbash, Brooklyn, NY 11209.  相似文献   

15.
《测量评论》2013,45(13):391-395
Abstract

In January, 1934, a report was received from the Royal Research Ship Discovery II that the positions of Inaccessible and Nightingale Islands in the Tristan d'Acunha group were incorrectly shown on British Admiralty chart No. 1769. The report originated from local information, and was to some extent confirmed by patent log distances run by Discovery II, and by sea sights, but no really definite evidence as to the correct position of the two islands was received. In effect, the report merely stated that both Inaccessible and Nightingale Islands were considerably nearer to Tristan Island than as charted.  相似文献   

16.
《测量评论》2013,45(25):136-140
Abstract

In a previous article on this subject (Empire Survey Review, January 1937) the writer sought to show that for trigonometrical observations of vertical angles made near noon in the Tropics the coefficient of refraction depends chiefly on height above ground level in the case of stations sited within a few hundred feet above the general level of the ground surface. Indeed, the computed values of the coefficient K show a definite and appreciable increase with “h”, the height of the observing station above ground level; it is usually assumed that K decreases with increase in height above the Mean-Sea-Level surface. From analysis of the results obtained by varying h but holding the heights above Mean Sea Level fixed the writer came to the conclusion that the variations in K could only be due to abnormal values of dt/dh and d2t/dh2, “t” denoting the air temperature. Now it is generally recognized by meteorologists that abnormal lapse-rates of temperature do frequently occur in the lower air layers in the Tropics; but up to the present time no temperature soundings in Nigeria are available. Recently, however, the writer came across the results of the aerological soundings made by an expedition in East Africa during the year 1908. The results of many of the soundings were of no use for the purpose of this paper; many of the observations were not taken at or near noon, and in others counterlapses of temperature in the lower layers indicated that conditions were not normal. A set of observations taken at Mombasa between 10 and 11 a.m. were eventually chosen as offering an example of what might reasonably occur in the lower layers of the atmosphere.  相似文献   

17.
《测量评论》2013,45(78):366-368
Abstract

The 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   

18.
《测量评论》2013,45(78):369-375
Abstract

The purpose of this article is to make available to readers of the Review a simple method of derivation from first principles of the projection farmulae for same of the more impartant normal conical projections.  相似文献   

19.
The authors describe common Soviet practice in the making of false-color composite imagery for visual interpretation. Also addressed are standard image interpretation techniques: figure-ground color contrast, color separation (number of color gradations occurring within an average contrast range), and so-called landscape indicator techniques. Related issues, such as selection of spectral bands and filters for specific interpretation tasks, and the changing reflectance characteristics of band-specific intermediate images, receive attention as well. Tables and figures illustrating relationships between photographic contrast, film contrast ratings, optical densities, and spectral bands are included. Translated from: Geodeziya i kartografiya, 1985, No. 4, pp. 41-46.  相似文献   

20.
Two general approaches for compiling maps of components of the water-ice budget in regions of glacier nourishment are compared and the resulting maps are analyzed. The compilation of raw data is based on field measurements rather than remote sensing information. Translated by Edward Torrey, Alexandria, VA 22308 from: Materialy glyatsiologicheskikh issledovaniy, 1991, No. 72, pp. 94-102.  相似文献   

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