摘要:

AbstractThe author describes a method of obtaining a Least-Squares solution to the simultaneous determination of Longitude and Azimuth, and Latitude and Azimuth, by the method of horizontal directions.

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.2

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor

摘要:

AbstractVertical collimation error in levels is normally eliminated using the two-peg adjustment. This adjustment assumes that Earth curvature and refraction are negligible, an assumption which appears to be justifiable. On a line of sight of 100 m, for example, the effect of curvature is 0·8 mm or 1·6 seconds of arc. The refraction effect is expected to be far smaller.

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.9

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor

摘要:

AbstractThe self reducing double image tacheometers described in this article are all based on the system patented by Bosshardt in 1922. The first production model of the Zeiss–Bosshardt (Redta) self reducing double image tacheometer came out in 1927, but it was not available in the U.K. till the early 1950's.

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.15

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor

摘要:

AbstractIn 1969 the National Board of Survey established an aerial camera calibration test field near to Jämijärvi, about 200 kilometres north-west from Helsinki. The first stage of the test field is now ready and there are 187 points distributed evenly on an area of 800×800 metres. The net has been divided into two orders (Fig. 1).

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.29

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor

摘要:

AbstractThe attraction of a spherical cap at a point situated above it, on the symmetry axis, is needed for various earth-gravity models, notably for the Bouguer effect.The attraction can be found through approximation or numerical integration procedures. Existing methods are reviewed.A modified approximation is derived, checked numerically, and found satisfactory for most practical cases.A rigorous solution is derived and checked theoretically and numerically.The various solutions are rated with regard to accuracy (better) and execution time (longer), as: Rigorous solution (1st), numerical integration (2nd), modified approximation (3rd), existing approximation (4th).

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.35

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor

摘要:

AbstractAn international conference on large sparse sets of simultaneous linear equations was held at St. Catherine's College, Oxford, from 5th to 8th April, 1970. It was organized by the Institute of Mathematics and its Applications, and it brought together many specialists from widely differing fields, all dealing with the problem of solving large sets of linear equations.

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.41

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.43

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.44

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.45

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor

ISSN:0039-6265    

DOI:10.1179/sre.1971.21.159.i

出版商:Taylor&Francis    

年代:1971

数据来源: Taylor