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1.
《测量评论》2013,45(71):16-19
AbstractField work for the 1/1,250 scale re-survey of Great Britain was fully described in an article by Brigadier R. P.Wheeler in the April, 1948, issue of this Review (ix, 68, 234–247). The object of this article is to outline the method’ of reproduction of these plans and of the resultant 1/2,500 scale plans of urban areas. The 1/2,500 series covering rural areas is a separate problem, one of revision rather than re-survey. Experiments are in hand now to find out the best ways to provide field material and produce the final plans on National Grid sheet lines. The 1/1,250 scale series will contain about forty thousand plans and the 1/2,500 series of the same areas about nine thousand. It is therefore important that production methods should be straightforward and maintain an economical balance between the use of men and machines. 相似文献
2.
《测量评论》2013,45(96):65-70
AbstractThe measurement of the temperature of a measuring band or bar has always been a major problem. A considerable a.mount of experimentation has been done on the morepreciseaspects of survey measurement, and attempts, ranging from packing measuring bars in ice to bimetallic apparatus, made to reduce temperature errors. At the present time electro-resistance thermometers are being used and an entire new field is being investigated using various waves for distance measurement. For at least some time in the future, however, these new techniques will not be sufficiently developed to be of practical or economic use to the cadastral surveyor. Nevertheless very much less interest is taken in what may be termed “bread and butter” procedures. 相似文献
3.
《测量评论》2013,45(28):322-326
AbstractIn reality the span of the working life of the Ordnance Survey is just short of the century and a half: whilst the map meridians that it has employed (in Great Britain alone) are, by just as little, over that figure. These meridians are, by the way, all respectable fully-fledged cartographic realities. They governed the computation of coordinates, the sheet-line distances, and the final plotting and fair drawing. None of your hastily added north points appear in this properly conducted family. 相似文献
4.
5.
《测量评论》2013,45(46):496-498
Abstract1. General.—The size of this Report has been curtailed as far as possible in the interests of economy of reproduction and stationery. The usual annexures giving details of the work in the Drawing Office, the Lithographic Reproduction Press, and the Trigonometrical Survey have been relegated to the Departmental Records for use as required. 相似文献
6.
《测量评论》2013,45(18):236-241
AbstractI. Introduction.-For some little time the Ordnance Survey was engaged upon the problem of transforming the rectangular coordinates of trigonometrical stations from the Cassini projection to the Gauss Conformal projection. The problem was complicated by the fact that the Cassini projection, as is well known, was applied to a number of meridians of origin, a different meridian being used for a county or a group of counties. It was proposed, however, to have only one meridian for the Gauss projection and to drop the county meridians completely. In both projections the northings were measured from the same parallel. 相似文献
7.
《测量评论》2013,45(18):248-250
AbstractGeneral.— The year 1934 has seen on the survey side an active continuation of trig. and cadastral surveys and on the land side standardization of procedure and routine. Good progress has been made in both branches. The surplus of revenue over expenditure, noted last year for almost the first time, has been very considerably increased, being of the order of eighty-two thousand dollars. 相似文献
8.
AbstractThis explains the formation of the Ordnance Survey of Northern Ireland as a separate institution in 1921, when it took over the map series which until that time had been part of the Ordnance Survey (U. K.) responsibility. As happened with many mapping organisations, replanning and reorganisation took place after 1945; this included a triangulation for Northern Ireland to provide a basis for a new Irt"sh Grid, and the introduction of the 1:1250 scale for major urban areas.The technical problems of reproduction and revision are then considered, and details given for each of the main series. 相似文献
9.
《测量评论》2013,45(28):334-338
AbstractI Hope Dr Wolff's interesting article will stimulate to action some of those who have not given sufficient attention to air survey as a method of mapping or planning those areas which lend themselves to that method. At the same time, whether so many of us are as conservative as the author appears to think is a matter for doubt, and moreover we do not all look upon air survey as an “innovation”. As Dr Wolff writes from Palestine he might be interested to know that as the second British Officer to take up field survey work in the War in 1915—Major (now Brigadier) Winterbotham being the first—I was one of the earliest in my profession to study, and to assist in the development of, air survey. In 1915 our unit in the 3rd Army was the first to make use of air photographs for the production of a regular series of trench maps. There are consequently few surveyors more interested in the method. I have watched the progress of the science and the work of the Air Survey Committee with continued interest and have used air methods whenever these have been possible or suitable. On my last visit to Paris I tried my hand at plotting with a new instrument at the Service Géographique and was much impressed by the work that was being done. 相似文献
10.
《测量评论》2013,45(8):105-108
AbstractAs air-photographs are being more and more used for survey purposes, Empire surveyors who have not yet made a thorough study of aerial survey may be interested in a little elementary photographic geometry and its application to map-making. A map may be described as an orthogonal proj ection of the ground upon a horizontal plane, reduced to some convenient scale, and a photograph as a conical projection of the ground upon the focal plane of the camera. If the focal plane is horizontal at the instant of exposure and the ground being photographed is perfectly level, the two projections are exactly similar and the photograph is indeed a map. Unfortunately these conditions which are illustrated in fig. 1 are extremely rarely encountered, and photographs usually need correcting for various distortions. 相似文献
11.
AbstractAlthough the title of this paper may appear to some to refer to a rather humdrum subject which hardly deserves much serious thought or consideration, it is the writer's experience that the vital necessity for keeping clear records of survey work in a permanent form in which they can easily be referred to at any future time is not always sufficiently appreciated by those whose duties do not involve constant or frequent reference to the records of old work. Accordingly, the following notes and suggestions, which are based on practical experience, may be of service in drawing attention to a matter which is really of great practical importance. 相似文献
12.
《测量评论》2013,45(63):14-20
AbstractFor some two months prior to the formation of the two companies, an intensive course of survey training and “refreshing” had been undergone by all ranks in the field sections, culminating in a combined Royal Artillery/Royal Engineer survey exercise from 1st to 10th October, carried out under operational conditions in all respects (even down to a 30-hour non-stop period of “photo-topo” compilation for the map on which the “final shoot” took place). 相似文献
13.
An absolute measurement of the gravitational acceleration “g” has been made at the National Standards Laboratory, Chippendale, N.S.W., Australia.
The determination was made by studying the free motion of a body projected vertically upwards in a vacuum and the time between
its initial and final passages through two horizontal planes of known vertical separation was measured.
The measured value ofg at a point 12 metres above the floor in room B. 37 of the National Standards Laboratory is 9.7967134 m/s2
The corresponding value at floor level at the BMR gravity station is 9.796717 m/s2
Paper presented at the meeting of the International Gravimetric Commission, Paris 7–11 September 1970. 相似文献
14.
《测量评论》2013,45(73):119-130
Abstract1. This new method of adjusting air photographs numerically to a uniform scale on a final map grid has already been described by the writert, where it concerns a large block-adjustment. The method to be described in this paper is the application of the same principle to the adjustment of photographic strips, covering narrow land areas and coastlines. 相似文献
15.
《International Journal of Digital Earth》2013,6(5):421-433
Abstract Sources of heterogeneous geospatial data such as the elevation, the slope, the aspect, the water network and the current settlements related to the known Neolithic archaeological sites of Magnesia, are used in an attempt to confirm the existence and allow for the prediction of other archaeological sites using predictive modelling theory. Predictive modelling allows the update of the problem solving strategy as soon as new data layers are available. The Dempster–Shafer Theory also commonly referred to as evidential reasoning (ER) is used to compose probability maps of areas of archaeological interest from physiographical and historical data. The advantage of this theory is that the ignorance is quantified and used to compose the probability maps named as belief, plausibility and belief interval for the archaeological sites. The final digital probability maps show that the Neolithic archaeological sites can be detected in the prefecture of Magnesia. This research study forms a methodological tool for the prediction of new archaeological sites in other areas of archaeological interest according to the physiographical and historical characteristics of the archaeological period being examined. It also contributes to the digital earth modelling and archaeological site protection, one of the most critical and challenging global initiatives. 相似文献
16.
《测量评论》2013,45(92):263-276
AbstractMost books on the technique of map compilation omit a detailed consideration of projections on the grounds that this subject is adequately treated at length elsewhere. Texts on map projections, however, are largely theoretical and rarely consider the practical problem of the proper choice and use of the graticules which are otherwise so ably described. An investigation of this little explored field has produced the following picture which it is thought may be of wider interest. A study of the fundamental properties which influence the choice of map projections is followed by a survey of projections in use, considered in relation to the fundamental properties. 相似文献
17.
《测量评论》2013,45(78):338-348
AbstractRadar can be applied to surveying for precise measuren1ent of long lines, and as a navigational aid and position-fixing device for an aircraft performing a photographic survey. Trials of the radar method have recently been carried out in Australia using a modified “Shoran” equipment. The results of a large number of radar measurements of six distances, varying from 160 to 310 miles in length, indicate that an accuracy of 7 parts in 105 can be achieved. Equipment errors constitute the immediate limit to accuracy, but reasonable modifications would yield a figure of 2 parts in 105. Radar measurements can be completed in a fraction of the time required by normal ground survey methods, since a measurement of upwards of a hundred miles is made in a single step.As an aid to photographic surveying a straight-line track indicator actuated by data from the “Shoran” equipment has been designed and flight tested. Its performance enabled a pilot taking aerial photographs to keep the aircraft to within an average departure of less than 0.02 mile from any desired straight-line flight path. 相似文献
18.
《测量评论》2013,45(20):343-346
AbstractA GOOD deal of astronomical work was called for during the operations of the British Somaliland–Ethiopia Boundary Commission. The method employed by the British Section for the determination of local time being that of star altitudes in the prime vertical, after the first few stations had been occupied the suggestion was made that the observer could be saved considerable strain by the preparation of a programme for time observations, much on the same lines as for latitudes. The proposal was tried, proved eminently successful, and became a standard part of the British Section's procedure. An example of such a programme is given below. I t is a little laborious, but simple. 相似文献
19.
Abstract Introductory.—From time to time the question of the relation between the metre and the foot is raised, most frequently perhaps from Africa. Had there been no more than a single metre to consider the question would no doubt arise but seldom: the most recent authoritative comparsion would be generally accepted. But actually it is the existence of two metres—the “ legal” and the “international”—which complicates the question, so much indeed that there is no metrological factor which has influenced survey, British and foreign, more than the relation between these two metres. The question was discussed in this Review (I, 6, 277, 1932), but memories grow shorter, attention is more diffused, and besides there is required a more explicit statement of the situation as it affects British surveyors, especially in Africa, whence the question has been raised anew. To illuminate it, unfortunately the need recurs to repeat some well-known facts. 相似文献
20.
Alexander V. Parshin Vladimir A. Morozov Anton V. Blinov Alexey N. Kosterev Alexander E. Budyak 《地球空间信息科学学报》2018,21(1):67-74
AbstractThe prospects for expanding the mineral resource base in many countries are linked with the exploration of stranded sites localized at unexplored areas with complex natural and landscape conditions that make any ground survey, including magnetic prospecting, difficult and expensive. The current level of geology requires high-precision and large-scale data at the first stages of geological exploration. Since 2012, technologies of aeromagnetic surveying with unmanned aircraft vehicles (UAV) enter the market, but most of them are based on big fixed-wing UAV and do not allow to substantially increase the level of survey granularity compared with traditional aerial methods. To increase the scale of survey, it is necessary to reduce the altitude and speed of flight, for which the authors develop the methodical and technical solutions described in this article. To obtain data at altitudes of 5 m above the terrain even in a rugged relief, we created heavy multirotor UAVs that are stable in flight and may be used in a wide range of environmental conditions (even a moderate snowfall), and develop a special software to generate flight missions on the basis of digital elevation models. A UAV has special design to reduce magnetic interference of the flight platform; the magnetic sensor is hung below the aircraft. This technology was conducted in a considerable amount of magnetic surveys in the mountainous regions of East Siberia between 2014 and 2016. The results of the comparison between airborne and ground surveys are presented, which show that the sensitivity of the developed system in conjunction with low-altitude measurements can cover any geologically significant anomalies of the magnetic field. An unmanned survey is cheaper and more productive; the multirotor-based technologies may largely replace traditional ground magnetic exploration in scales of 1:10,000?1:1000. 相似文献