1 1 PHOTOGRAMMETRY GENERAL Photogrammetry can be defined

Тема № 1. ЗАДАНИЕ 1. Прочтите и переведите текст на русский язык PHOTOGRAMMETRY. GENERAL. Photogrammetry can be defined as the method of determining the shapes, sizes and positions of objects using photographs, and it is, in the main, an indirect method of measurement since photographic images are under study rather than the objects themselves. Some linear or angular measurement in the "space" need to be known for control purposes, but primarily the photography provides the information. Photogrammetry has been developing for over ones hundred years. For instance the Frenchman Laussedat published a paper on the subject in 1854, and the Royal Navy is known to carry out photographic reconnaissance of coastal regions in the Baltic in that year. Two main branches can be identified from the mapping aspect, namely aerial photograrmmetry and terrestrial photogrammetry. The aerial photogrammetry is the more important and it involves the use of photographs taken in a systematic manner from the air. They are then controlled by land survey and measured by photogrammetric techniques. Accuracies achieved are comparable with those obtained by land survey and in many cases the work is carried out more economically. The same air photographs may be used for a number of simple measurement techniques and for visual interpretation to provide much valuable information. Terrestrial photogrammetry existed before aerial photogrammetry but to-day it is of relatively minor importance, it is only used for mapping purposes in situations where aerial photogrammetry is unsuited, a. g. areas and broken terrain, small site surveys. Airphotos are an excellent and versatile tool for mapping, for urban and rural planning. Used properly, airphotos can help planners save both time and money, improve the accuracy of their work and help them explain to the public the problem of change and the benefits of good planning for rural counties, small town, cities etc. ЗАДАНИЕ 2. Пересказ ЗАДАНИЕ 3. Анализ текста по специальности

ОПРЕДЕЛИТЕ БЕЗ СЛОВАРЯ ЗНАЧЕНИЕ СЛОВ И СЛОВОСОЧЕТАНИЙ ИЗ ТЕКСТА. n n n n n Photogrammetry position of objects photograph information region Baltic aspect aerial photogrammentry economically techniques situation airphoto problem photointerpretation camera methodical procedure mosaic

Тема № 2. ЗАДАНИЕ 4. Прочтите и переведите текст на русский язык PLOTTING AND MEASUREMENT When the phot graphic process has been completed, measurements сan be taken from the photographs by a number of different methods which are dependent upon the required end product, e. g. a. line mар with heighting information thereon. The most accurate methods o£ measurement are of a rigorous form and involve the formation of a stereomodel, which is an exact replica of the ground, at a reduced scale, from each, stereopair of photographs. This stereomodel is formed when the two camera positions and camera title, as at the time of photography, have been re-established. This is usually carried out in a photogrammetric plotting machine or stereoplotter. These make use оf pairs of overlapping photographs which are normally in the form of dispositives on film or glass rather than paper prints. Such machines produce three-dimensional models of the terrain from two photographs and thence ensure the accurate plotting and heighting of features within the models without calculations, or, alternatively, the determination of co-ordinates in the models. Two central perspectives must be arranged and the corresponding rays caused to intersect to form the model, the plot then being produced ortogonally. Projection can be effected either mecanically, optically or by optical-rechanical means, the maps required for civil engineering projects are often at large scales (1: 500 -1: 2500), and to obtain sufficiently accurate measurements, first-order machines must be used. These are commonly based on mechanical projection, as in Wild a 10. Three steps are to be followed when establishing the stereo-medal, namely inner orientation, relative orientation and absolute orientation. The internal geometry of the air camera used during photography is established in the plotting machine in the first step. The perspective centers of the projection system are set at a distance equal to the principle distance of the air camera from the plane of the photograph and the principal points of the photographs and the projection systems are made to coincide. The projected bundle of rays will not be congruent with that which that entered the air camera at the time of photography. Relative orientation places the pairs of photographs in their correct relative positions, and, when completed, a stereomodel is formed by the intersection of the corresponding rays. During absolute orientation the stereomodel is rotated until it lies, in its correct relationship to the datum plans above which heights are to be measured; it is also scaled and set in its correct azimuth. Alongside the plotting machine and liked to it, is a plotting table. The end products of plotting may be in the form of line maps photomaps and diginal terrain models.

ЗАДАНИЕ 5. Переведите предложения, учитывая контекстуальное значение слов «time » , «times » . «time» , «times» . 1. The experimenters spent a lot of time over that work. 2. All the time they worked. 4 time 3 equals 12. Space and time are fundamental conceptions. In recent times ideas about the upper layers of the atmosphere have changed. The students carried out an experiment locking at thermometer from time to time. It Is high time to begin to work. Lomonosov lectured at the University and at the same time he worked in different fields of science. I work at the laboratory two times a week. 3. 4. 5. 6. 7. 8. 9. Дайте русские эквиваленты следующим словам и словосочетаниям. n n n rigorous form reduced scales overlapping photographs paper print accurate plotting neighting of features corresponding rays optical-mechanical means the projection system the bundle of rays intersection of rays plotting machines Найдите в тексте английские эквиваленты следующих слов и словосочетаний: n n n n проводить измерения зависеть от … конечный продукт точный метод измерений во время снимка определение координат точек пересекаться а именно в виде диапозитивов совпадать относительное положение пересечение по азиумуту

Тема № 3. ЗАДАНИЕ 7. Прочтите текст и поставьте к нему вопросы (на английском языке) STEREOSCOPES For some applications of aerial photogrammetry a lower order of accuracy is acceptable and there a number of measured techniques which employ simple and inexpensive instruments. For stereoscopic observation, pairs of photographs must be arranged so that the lefthand picture, and the right eye observes the sight-band picture only. The two images combine in the brain to give a single image of the common overlap, which gives an impression of relief in a manner similar to an observer himself looking over the terrain. One of the simplest and most common aids to produce this stereomodel is the stereoscope, of which there are two main types the pocket stereoscope and he mirror stereoscope. The pocket stereoscope is cheap, portable and very suitable for field use but it is difficult to use with air photographs which are 230 mm square, and accordingly the mirror stereoscope is the more popular. This provides for a physical separation of the two airphotographs even when they are 230 mm square, by employing double reflection of the rays off a system of mirrors (at 45° to the horizontal). Simple formulas, have been developed to determine the heights on the objects. ЗАДАНИЕ 8 Перевод статьи по специальности.

Тема № 4. ЗАДАНИЕ 9. Прочтите текст и переведите его на русский язык ORTHOPHOTOMAPS. An Orthophotograph product from which the distortions due to ground relief and tilt have from been removed and as a result the orthophotograph possesses the geometrical characteristics of a map. Such a photograph cannot be taken from air and it needs to be a conventional plotting machine. Initially she stereomodel is set up in its correct absolute orientation in the plotting machine. In principle the model is now divided into a series of parallel strips and then subdivided into small linear elements by means of a narrow slit. Movement of this slit is directly related to movement of the floating mark is the plotting machine but instead or the operator following individual features, the model is now systematically scanned in the X or Y direction, the floating mark being continuously maintained on the surface of the stereomodel by the operator. At the same time, an orthonegative film, free from relief and tilt displacement, and at a uniform scale, is exposed through the slit as it moves along each strip. The orthonegative, therefore, retains all the detail presented on the original photograph unlike a conventional line map where a selection of detail present has to he made by the operator. In the above procedure, the orthonegative is produced at the same time as the measuring procedure in the stereo-plotter and the projection in the orthophoto instrument. It is, however, possible, to use many orthophotosystems in an off-line mode. This requires the use of a storage device in which the profile data or contours can be digitally stored during scanning and then used later to control the expose of the orthophoto. The off-line mode of operation has many advantages over the on-line mode.

Тема № 5. ЗАДАНИЕ 10. Прочтите текст и переведите его на русский язык DIGITAL TERRAIN MODEL. A digital terrain aiodel can be defined ae a statistical s&spling of the X and Y and Z. co-ordiuates of the terrain, i. e. ground surface, so that by interpolation the Z co-ordinate of any point can be accurately estimated from the X, Y co-ordianates. The morphological shapes must therefore be properly represented by the co-ordinated points chosen, and not only should those Z coordinates be established to the required, accuracy, but the points should be sufficiently numerous and adequately arranged. Data for a DTM mау be gathered by land survey, photogrammetry or from аn existing map. Special co-ordinates of thefle characteristic points may be stored in the computer to allow the interpolation of other points. Then forming а DTM, the accuracy of measurement of individual points obtaned by photogrammetry is tower than that which can be obtained by ground survey methods. Photogrammetric measurement is more points may be measured and comparative tests indicate similar overall accuracies is after interpolation. However the potential of the DTM can be fully exploited when it is used in conjunction with a computer and associated software.

Тема № 6. ЗАДАНИЕ 11. Прочтите текст и поставьте к нему вопросы (на английском языке). Перескажите текст на английском языке. MOSAICS If a set of overlapping vertical photographs is joined to - gether, rough map or serial view, of the area is obtained which has no uniformity of scale. This is called an uncontrolled mosaic, and its assembly calls for such skill since relief and. tilt distortions which occur in each photograph inevitably, cause, a mismatching of detail between adjacent photographs. That is why only the center, portions of the photographs, where distortions are least are used. The mosaic is assembled usually from the centre outwards and if required, features, such as reads, rivers etc. can be emphasized, and lettering added. The mosaic is then rephotographea so that the final appearance is that of a single photograph. The mosaic can be of great assistance at the reconnaissance and planning stage as it contains all that which would be se-en directly from the aircraft at the time pf photography. The photographs show such points as the type and density of any development, and use, alterations in topography etc. It reveals information in far greater detail then can- be plotted, on a map. Lettering – подписи на карте

Переведите предложения с английского языка на русский язык, обращая внимание на слово «that» Surveying is a science that interests many specialists. 2. The party has surveyed the part of the terrain already. 3. We know that a level line is considered as mathematically straight. 4. That the earth is round was know long ago. 5. Then forming a DTM the accuracy of measurement of individual points obtained by photogrammetry is lower than that which can be obtained by ground methods. 6. The projected bundle of rays should be congruent with that which entered the air camera at the line of photography. 1.

Тема № 5. ЗАДАНИЕ 12. Прочитайте и переведите . Applications of airphoto. 1. Included among the many applications of airphotos for planning are the following: 2. The airphoto itself may be used as a type of map. 3. The airphoto, with identifying marks and annotations shown on the photo itself or on an overlay, may be used as a map pase. 4. A number of overlapping airphotos may be connected to form an airphoto mosaic. 5. One or more airphotos may be used as information and education devices. 6. Photogrammetry has two basic types of used for planning: measurement and map-making. Measurement. Many kinds of measurement needed for planning studies can be made from controlled airphoto mosaics or from single airphotos; still others can best be made from stereopairs of airphotos. Their relative accuracies vary, so the type of airphoto and the method of measurement will depend on the procession needed for each particular job. Various devices have been invented to aid in making quick, accurate measurement from airphotos. Areas can be measured with a planimeter, or with a dot or circle grid. Height can be measured with a parallax bar or a stereoscope viewer utilizing a “float dot”. Mapping. Airphotos are useful in preparing new base maps or bringing old ones up to date. They are also very useful for preparing many other types of maps, including resource maps, land-use map and ownership maps. Base maps. If an up-to-date, accurate base map adequate scale is not available a new base map should be made. Also, if the area being studied is once of great change-such as an urbanizing country – it may be quicker and less expensive to have a new base map prepared then to bring an old base map up to day. Airphotos can be used as the primary source of data for the preparation of base maps. Skilled photogrammetriats use stereoscopic airphotos and stereoplotting machines to make the base anuacripts needed both for topographic and planimetric maps. If available photography is inadequate or not sufficiently upto-date, new photography should be made. The cost of airphotos, even if new ones are needed, is only a small part of the total cost of mapping. If new photography is needed, the steps are: n Determine purpose for which the map will be used and the type of map needed; n Review the area to be photographed, using existing map sources; n Determine approximate flight lines and altitude, selecting camera types, lens focal lengths and film and filter types to provide the scale and type of photography needed; n Photograph; n Develop and print; n Establish ground control after analysis of developed photo strips; n Prepare map manuscript by photogrammetric means and print map.

ЗАДАНИЕ 14. Прочитайте и переведите LAND USE MАР Planning the development of аnу area requires in addition to socio-economic data, knowledge of the area's topography, physical structure and the natural resources. Airphotos and photogrammetric procedures аre need for the preparation of topographic maps, such as those made by the U. S. Geclogical Survey, which shows contours of the land, water courses and their drainage - terns, wetlands, forests and numerous cultural features. Airphotos, together with field surreys, also can be used to map soils, geologic structure, and mineral deposits. On airphotos, general land uses say be identified, classified, measured and delineated. The land as data can then be transferred to a copy or a base may or to an airphoto mosaic. For more detailed land-use surveys, supplemental data can then be transferred to a copy or a base map or to an airphoto mosaic. For more detailed land-use surveys, supplement data not shown on airphotos should be gathered thought field checks. Enlargements of airphotos are excellent for use as field worksheets. For rural areas, enlargements of 1 n = 500, 1 n = 700 or even, 1 n = 800 are adequate. For cities, towns and villages, enlargements or of 1 n – 200 are better.