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1.
《测量评论》2013,45(22):469-476
Abstract

A Brief account of a survey, recently completed by me, of a block of land situated in Northern Rhodesia and some 3,000,000 acres in extent, may be of interest. The sketch-map opposite shows the geographical situation and.exterior boundaries of this block of land. It is seen that it stretches along the entire length of the Northern Rhodesia-Tanganyika Territory border, which is approximately 150 miles in length.  相似文献   

2.
《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   

3.
《测量评论》2013,45(53):278-279
Abstract

In the October 1943 number of this Review (vii, 50, 161–2) Mr. Lawes makes some comments on the original article by the present writer (vi, 45, 402–7). It seems necessary to state more clearly the general intention of the original article and also to reply to some of the comments.  相似文献   

4.
《测量评论》2013,45(62):311-314
Abstract

In 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   

5.
G. M. T. 《测量评论》2013,45(23):49-53
Abstract

That admirable annual, The Surveyor (Ceylon), was generously forwarded to us some months ago. In this issue, vol. 2, no. 4, p. 93, there is given the solution of a question on resection in an examination paper. Since the solution appears rather laboured and the problem is interesting in itself and by no means valueless, it seems not out of place to attempt a simpler and more obvious answer.  相似文献   

6.
《测量评论》2013,45(87):36-39
Abstract

MR. RAINSFORD'S paper on Directions versus Angles in the Least Squares Adjustment of Triangulation in the October 1950 issue of the E.S.R. (x, 78, 353–366) has raised some interesting points and has prompted me to put on paper my own views and some of the results of my own experience.  相似文献   

7.
《测量评论》2013,45(7):7-12
Abstract

In his article “Standards of Length in Question” published in the last number of this Review (Vol. i, pp. 277–-84) Captain G. T. McCawgave us most interesting and valuable history concerning the questionable past of the international metre. He has, it may be assumed, exhausted published evidence; but he states that he can find no reference to invitations from this country to France and Holland to send their fundamental standards for comparison with others at the Ordnance Survey in the eighteen sixties.  相似文献   

8.
Abstract

Although methods of map preparation and production in the nineteenth century are generally understood, in truth little is known in detail. A rare opportunity to further understanding of the methods of the day is offered by the analysis of the surviving working documents and correspondence related to the production of town maps for Lysons' Magna Britannia. As methods of compilation and preparation become clearer, some of the resultant town maps appear more original and carefully created than previously thought, forcing a reassessment of their value as historical evidence.  相似文献   

9.
The multiresolution character of collocation   总被引：3，自引：0，他引：3  
 An interesting theoretical connection between the statistical (non-stochastic) collocation principle and the multiresolution/wavelet framework of signal approximation is presented. The rapid developments in multiresolution analysis theory over the past few years have provided very useful (theoretical and practical) tools for approximation and spectral studies of irregularly varying signals, thus opening new possibilities for `non-stationary' gravity field modeling. It is demonstrated that the classic multiresolution formalism according to Mallat's pioneering work lies at the very core of some of the general approximation principles traditionally used in physical geodesy problems. In particular, it is shown that the use of a spatio-statistical (non-probabilistic) minimum mean-square-error criterion for optimal linear estimation of deterministic signals, in conjunction with regularly gridded data, always gives rise to a generalized multiresolution analysis in the Hilbert space L 2(R), under some mild constraints on the spatial covariance function and the power spectrum of the unknown field under consideration. Using the theory and the actual approximation algorithms associated with statistical collocation, a new constructive framework for building generalized multiresolution analyses in L 2(R) is presented, without the need for the usual dyadic restriction that exists in classic wavelet theory. The multiresolution and `non-stationary' aspects of the statistical collocation approximation procedure are also discussed, and finally some conclusions and recommendations for future work are given. Received: 26 January 1999 / Accepted: 16 August 1999  相似文献   

10.
《测量评论》2013,45(90):159-165
Abstract

The duties of an Extension Officer of the South African Division of Soil Conservation and Extension are many and varied. Briefly, he gives professional advice on all aspects of farming (except veterinary), technical advice on engineering and building construction applied to farming, he does surveys and advises on dams, contour banks, etc., carries out stocks improvement and seed inspections, enforces the Weeds Act, and last but not least, sees to the enactment of the Soil Conservation Act. In these duties it is considered that one officer and two assistants are necessary for every 200 farms. Johnny Coles, B.Sc., with one full time, and occasional part-time, assistance has, as extension officer in the Ixopo district in Natal, over 1,000 farms comprising 1,800,000 acres, and a considerable number of government-owned properties in his care. Many men in his position would, in desperation over the hopelessness of the task, let things slide. Not so Johnny Coles who set about finding ways and means of getting the work done somehow.  相似文献   

11.
Based on the estimating rule of the normal vector angles between two adjacent terrain units, we use the concept of terrain complexity factor to quantify the terrain complexity of DEM, and then the formula of terrain complexity factor in Raster DEM and TIN DEM is deduced theoretically. In order to make clear how the terrain complexity factor E CF and the average elevation h affect the accuracy of DEM terrain representation RMSE Et , the formula of Gauss synthetical surface is applied to simulate several real terrain surfaces, each of which has different terrain complexity. Through the statistical analysis of linear regression in simulation data, the linear equation between accuracy of DEM terrain representation RMSE Et , terrain complexity factor E CF and the average elevation h is achieved. A new method is provided to estimate the accuracy of DEM terrain representation RMSE Et with a certain terrain complexity and it gives convincing theoretical evidence for DEM production and the corresponding error research in the future.  相似文献   

12.
《The Cartographic journal》2013,50(2):115-116
Abstract

An assessment is made of the accuracy of the map and written survey, which is essentially a list of land-holders and the areas held by each, and of their mutual consistency. The geometry of the map is compared quantitatively with that of the first edition (1852) Ordnance Survey 6-inch (1 : 10 560) map. The Saxton map is found to have a scale of 1 : 5140, leading to the conclusion that the perch used in the scale bar represents 71/9 yards or thereabouts. The areas quoted in the written survey are consistent with acres based on this value. The positional accuracy of points on the map is found to be ～20 m, and areas of typical plots determined from the map are uncertain by between about 4 and 12%. The relationship between these two facts can be understood through a detailed study of the statistics of the errors in separations of points on the map. The written survey is found to omit a substantial number of plots of land from its listings. The map thus appears to be more reliable overall than the written survey.  相似文献   

13.
G. T. M. 《测量评论》2013,45(35):285-296
Abstract

In 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   

14.
《测量评论》2013,45(20):334-336
Abstract

In a tale, delightfully told in vol. ii, no. 8, pp. 121–2 of this Review, Mr. Kitching revealed how he was called upon to assist in determining the length of an Arab mile. In the notes following the story a reference was made to measurements of arc carried out in the ninth century A.D. The following notes add some more details to those already given. The full table of the Arab units of length is given below; in the reference above, one step was left out.  相似文献   

15.
《测量评论》2013,45(11):268-278
Abstract

Colonel MacLeod has already given in this Review (vol. i, 151–6, 207–14, 253–9) an excellent general account of the activities of the Field Survey Units in the Great War, but perhaps the details of some of the problems that presented themselves and the personal experiences of a Field Survey Officer may still be of some interest.  相似文献   

16.
Abstract

Close-range hyperspectral images are a promising source of information in plant biology, in particular, for in vivo study of physiological changes. In this study, we investigate how data fusion can improve the detection of leaf elements by combining pixel reflectance and morphological information. The detection of image regions associated to the leaf structures is the first step toward quantitative analysis on the physical effects that genetic manipulation, disease infections, and environmental conditions have in plants. We tested our fusion approach on Musa acuminata (banana) leaf images and compared its discriminant capability to similar techniques used in remote sensing. Experimental results demonstrate the efficiency of our fusion approach, with significant improvements over some conventional methods.  相似文献   

17.
《测量评论》2013,45(48):50-56
Abstract

In the memoir of the late Capt. G. T. McCaw which appeared in the January number of this Review (vii, 47,2), reference was made to the part which the late Sir David Gill played in the origin of the work on the survey of the Arc of the 30th Meridian in Africa. This year is the centenary of Gill's birth, as he was born in June 1843, and it is therefore timely to give some account of his work during his long term of office as Her Majesty's Astronomer at the Cape which resulted inthe inception and completion of the Geodetic Survey of South Africa and the survey of the Arc to the southern shores of Lake Tanganyika. He died on 24th January 1914.  相似文献   

18.
A method for filtering of geodetic observationwhich leaves the final result normally distributed, is presented. Furthermore, it is shown that if you sacrifice100.a% of all the observations you may be (1−β).100% sure that a gross error of the size Δ is rejected. Another and, may be intuitively, more appealing method is presented; the two methods are compared and it is shown why Method 1 should be preferred to Method 2 for geodetic purposes. Finally the two methods are demonstrated in some numerical examples.  相似文献   

19.
《测量评论》2013,45(64):52-70
Abstract

In the last instalment we were able to obtain most of the surveyor's projections in common use by applying simple scale conditions to the meridians and parallels. This method of approach naturally suggests that results of some value might be obtained by applying similar conditions to the plane co-ordinate lines. If we do so, we are immediately led to consider curves on the surface known as geodesics, which are the nearest approach to straight lines it is possible to draw on a curved surface. Accordingly, we give some account of these curves for the benefit of surveyors who have not hitherto made their acquaintance.  相似文献   

20.
G. T. M. 《测量评论》2013,45(36):368-371
Abstract

In the table appended there are given statistics of some recent ordinary traverses in the Gold Coast Colony. These have been executed by European (E) or African (A) surveyors, departmental (D) or licensed (L). They apply to Acquisitional, Concessionary, and Proprietary Surveys of various classes of property. The traverses consist either of self-closing circuits (C), or of circuits closing on lines of fixed length and bearing (F). The equipment comprises a theodolite, steel band, and temporary wooden pegs carrying vertical, partially driven nails as centring marks. The table is self-explanatory with the exception of the final column, where the significance of “K” will perhaps be explained by some member of the Department.  相似文献   

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