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1.
J. H. R. 《测量评论》2013,45(18):226-235
Abstract

We have seen that a few constellation-names used by us to-day make their appearance as far back as the Homeric poems, while the star-names Sirius and Arcturus are found in the works of Hesiod. We saw no reason to suppose that these early poets knew no names for other groups. They mentioned only those conspicuous heavenly objects that might occur in any general literature, as for example in the Old Testament books of Job and Amos. There are sporadic references to constellations in the extant works of the great Greek tragedians of the fifth century B.C., but these give us few additions to the Homeric list'. It is not till we come to the special literature of the subject that constellation-names appear in any quantity. The first specialist whose name stands out is the mathematician Eudoxus of Cnidus, a disciple of Plato, who lived in the first half of the fourth century B.C. He wrote a prose work entitled the “Phaenomena”, which, though unfortunately lost, was rendered into verse by the poet Aratus about 275 B.C.  相似文献   

2.
J. H. R. 《测量评论》2013,45(16):98-105
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3.
秩亏Gauss—Markov模型参数的有偏估计   总被引:3,自引:0,他引:3  
归庆明  黄维杉 《测绘学报》1997,26(3):261-267
本文讨论秩亏自由网平差中系数阵存在严重复共线性时参数的有偏估计问题。通过引入秩亏Gauss-Markov模型的典则形式,将秩亏Gauss-Markov模型参数的有偏估计问题转化为满秩Gauss-Markov模型参数的有偏估计问题,由此提出了未知参数的一个有偏估计类,并讨论了它的优良性质;通过适当选择变换矩阵,构造了许多很有价值的有偏估计,其中包含的偏参数都能通过满秩Gauss-Markov模型确定  相似文献   

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《测量评论》2013,45(96):75-81
Abstract

Because it was necessary to calculate the longitude many times from observed ex-meridian zenith distances, it was considered advisable to examine the various methods for achieving this in order to find which method was the most efficient.  相似文献   

6.
《测量评论》2013,45(71):37-39
Abstract

DR. DE GRAAFF-HUNTER proposed two new astronomical methods in a paper which he read at the Conference of Commonwealth Survey Officers, and the writer recently had an opportunity of trying out one' of these, with some interesting results. The method used, which requires timed intersections on a pair of stars in azimuths differingby about 90° and depends upon the alg'ebraic solution of the pair of position lines so formed*, will yield latitude, longitude and azimuth. The observations are brief and uncomplicated, prior identification unnecessary",and ~4e subsequent. computation is light: and requires no more than about thirty minutes for a pair of stars, inclusive of star identification.  相似文献   

7.
《测量评论》2013,45(97):124-132
Abstract

The article discusses an observation consisting of pointings made to two stars on opposite sides of the meridian, the altitude in each case being set equal to the star's declination.  相似文献   

8.
《测量评论》2013,45(18):241-242
Abstract

In working out vertical heights on the Akuse-Kete Krachi chain of triangulation in the Gold Coast a fairly considerable difference was found between values of the coefficient of refraction obtained from observations taken during the day and those taken at night, the mean values being 0.069 for daylight observations to heliographs and 0.087 for night observations to lamps. This difference no doubt is due mainly to the condition of the atmosphere during the day differing from its condition during the night rather than to any effect due to different sources of light. A new chain has recently been observed in Western Ashanti, and the index of refraction for the daylight observations again gave a lower value than that obtained from the night observations, the figures being 0.073 and 0.099 respectively. For the night work three different sources of light were used, hurricane lamps for short lines, Tilley vapour-pressure lamps for lines of intermediate length, and McCaw acetylene signalling lamps by Watts for long lines. It occurred, therefore, to the writer to examine the results to see if the mean values of the index of refraction showed any variations for the different light sources, since it seemed reasonable to suppose that the constitution of the light emitted from each source would be different and hence that the coefficient of refraction might vary.  相似文献   

9.
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   

10.
The theory of the solution of the stereogram is developed from the condition that the vector triangle, formed by the base-line and the two rays from the perspective centre to a common model point, shall be in equilibrium. Using this approach the unique definition of a point in the model follows naturally from the solution of the relative orientation problem.  相似文献   

11.
《测量评论》2013,45(91):206-210
Abstract

The observations to height Kilimanjaro were made from two ground stations, Domberg (5,081·6 ft.) and Lelatema (5,323.1 ft.) and from a point called Kibo near Kaiser Wilhelm Spitze which is regarded as the highest point on the crater rim. It was originally intended to include a third ground station, Kifaru, but it was discovered that the ice cap obstructed observations between this point and the top.  相似文献   

12.
本文从六个方面阐述了地图形式美的规律性,最后进一步说明了其规律性与增强地图美感的关系。  相似文献   

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15.
《测量评论》2013,45(37):429-436
Abstract

Gauss's method of collimation is usually given scant attention in survey text-books. The following notes are based on experiments carried out at Accra in making a collimation base, the collimator being a Watts 2I-inch self-adjusting level fitted with a parallelplate micrometer.  相似文献   

16.
地壳形变干扰因素有效性的判别   总被引:3,自引:0,他引:3  
刘权威 《测绘学报》1996,25(2):95-103
建立地壳形变模型时需要考虑外界因素的影响,为此必须判断外界干扰因素显著性,常用的经典方差分析判别法要求干扰因素之间是相互独立的,而实际上干扰因素之间经常产苤满足这一条件,本文提出基于加权最小二乘准则下的方差分析理论,它容许干扰因素之间互相相关,从理论上较好地解决这一问题,文中导出和论证了相应的公式,并以实例讨论了它的应用。  相似文献   

17.
《测量评论》2013,45(23):16-20
Abstract

This paper is written primarily with the object of ascertaining how other Colonies and Dominions deal. with the adjustment of their trigonometricallevels; further, since the greater part of Nigeria is now covered by a framework of levels of primary accuracy it is of interest to examine the results. Moreover, the evaluation of the coefficient of refraction, and from it the temperature lapse-rate, is of some importance in view of the recent publication of the War Office Aneroid Tables. These tables are based on a standard lapse-rate of temperature.  相似文献   

18.
19.
《测量评论》2013,45(3):131-133
Abstract

Up to 31st March 1922, the work in Ireland with regard to the revision and supply of Ordnance Survey Maps was governed by similar rules to those existing at the Ordnance Survey of Great Britain. No changes were made in the Irish Free State until the revision of Co. Waterford was completed on the 25-inch scale in 1923. It was then decided to depart from the usual procedure of taking up the work of the revision of Counties according to a cycle of years, and to revise those particular portions of the country in which extensive alterations had been carried out by reason of the division of properties by the Congested Districts Board and the Irish Land Commission. Accordingly, those portions of Counties Galway, Mayo and Roscommon which had undergone the greatest development were taken up for revision. In all eighty-nine sheets were specially revised and completed by 1928.  相似文献   

20.
利用卫星测高资料推求西北太平洋海域的海洋大地水准面   总被引:3,自引:0,他引:3  
李明  梁振英 《测绘学报》1997,26(4):344-351
本文根据卫星测高数据和海面动力地形资料,绘制了不相上下北太平洋海域局部大地水准面的精细结构图,对解决卫星测高技术中大地水准面积和海面地形的可分性问题作了初步尝试。  相似文献   

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