International cooperation and technology transfer

Fras, Mojca Kosmatin

Bibliographic data

Monograph

Persistent identifier:: 856490555

Author:: Fras, Mojca Kosmatin

Title:: International cooperation and technology transfer

Sub title:: Ljubljana, Slovenia, February 2 - 5, 2000 : proceedings of the workshop

Scope:: VI, 163 Seiten

Year of publication:: 2000

Place of publication:: London

Publisher of the original:: RICS Books

Identifier (digital):: 856490555

Illustration:: Illustrationen, Diagramme

Language:: English

Usage licence:: Attribution 4.0 International (CC BY 4.0)

Publisher of the digital copy:: Technische Informationsbibliothek Hannover

Place of publication of the digital copy:: Hannover

Year of publication of the original:: 2016

Document type:: Monograph

Collection:: Earth sciences

Chapter

Title:: USAGE OF AERIAL PHOTOGRAPHS. Ivan Landek, Stanislav Franges

Document type:: Monograph

Structure type:: Chapter

102 element contains, apart of its own exactly determined position, a definite information - grey value (Stefanovic et al., 1998). Since the image is generally not strictly vertical, the prespective image will deformed even in the case of strictly horisontal land. The transformation of thus defromed image into the corrected one that will correspond to the orthogonal plan projection in a certain scale is called redressing. The differential redressing makes it possible to obtain the image transformed not only into the orthogonal, but also to any other map projection (Lapaine and Francula, 1998). Digital orthophotoplan is a geometrically corrected photography in digital form resulting from the computing transformation of digital images from the central into the orthogonal projection. The process of computing the digital orthophoto plan can be devided into geometric and tone correction of the digitally scanned image. The first part encompasses the correction of scale errors and of prespective deformation, and the other part relates to the elmination of unequalities in the intensity of the blackening. The orthophotoplan is practically an orthogonal projection of the surveyed area and integrates thus the advantates of the classical geodetic plan and photoplan. The corrected photography is the basis for a map in photographic form - orthophotomap, supplemented by the contour lines or contour values charaterizing the terrain configuration or relating to the important positions, than by the toponomastic of the regions, municipalities, settlements, relief features, hydrography etc., by the symbols for geodetic points (trigonometric, orientation, levelling, possibly traverse etc.), by letter and number symbols accompnying the traffic routes and by other data (Biljecki and Tonkovic, 1999). 2.1 Cyclical survey in the Republic of Croatia In the West-European countries, the updating of maps is much more preferred than the production of new maps. For the purpose of updating, one plans cyclical photogrammetric surveys in the period of 3 to 7 years. On the basis of the obtained images the sheets of topographic maps at a definite scale are produced (State Geodetic Administration, 1995). In the period between 1990 and 1996, the aerial survey has been interrupted because of the war and the fighting for the independence of the Republic of Croatia. While the war was still going on, the experts were already thinking about the period after the war and about the establishment of aerial photogogrammetric service. Referring to the war conditions, the State Geodetic Administration has made a decision to start with cyclical surveying in the northwestern part of the Republic of Croatia, at the territory of Istria. In 1996 the western part of Istria from Umag to Pula (on Fig. 1 the area is marked by the hatching with thin line density) was surveyed. After the state needs had been thoroughly analysed, the decision was made to continue with cyclical survey according to priorities. Hence, in May 1997, the northwestern part of Croatia was surveyed. At the same time, the surveys started to be performed in the southwestern part of Croatia. Due to very good weather conditions, one started with surveying at the territory of Lika, and of the cities Zadar, Sibenik, Split. Because of the new situation in Slavonija, and because the war stopped and it was necessary to collect the photographic material of the devastated area, this area started to be surveyed. In the meantime, it was urgent to survey a broader area of the City of Zagreb to widen earlier planned area of Lika - Zadar - Sibenik - Split (Landek and Kauric, 1998). On Fig. 1 the areas photographes in the period between 1997/98 are marked by the hatching with medium line density. For the period of 1999/00 all other areas have been covered by agreements and partly photographed, and they are marked by hatching with the highest density of lines on Fig. 1. High quality photographic magnifications at the scale of 1:10 000 or 1:20 000 can be made from aerial photographs at the scale of M s = 1:31 600. Referring to the legibility of a negative of at least 50 lin/mm, it is possible to spot the details having the absolute size of 9,5 m. Wit good magnification one can expect the legibility of details at the magnifications of at least 1 m which is rather satisfactory for the scale of 1:10 000 (State Geodetic Administration, 1995). 3. APPLICATION OF AERIAL PHOTOGRAPHS The application of photogrammetry in Croatia has so far been oriented mostly towards gathering and processing land and topographic data, i.e. more recently to the creation and establishment of land databases, mostly within the frame of geodetic spatial system (GEOPS) as the basic infrastructure for almost all activities dealing with space, and for the most spatially connected information systems. Thus, the exceptional importance of photogrammetry for the processes of spatial arrangement and systematic environmental protection, as very important tasks of a modern man is manifested. Referring to the experiences gathered and to the solid preconditions, it is not unrealistic to expect such a trend to be continued in our country in the future as well, but resulting in even better achievements (Krizaj, 1998). The development of digital photogrammetry has influenced remarkably the increase of the demand in scanned aerial photographs. Digital aerial photographs have been used lately in the first place for the purpose of producing digital orthophoto plans. Except for geodetic purposes, the scanned aerial photographs can be applied in other branches as well, e.g. in archaeology, geology, geography, hydrotechnics, agriculture, forestry, environmental protection, for military purposes etc. In order to avoid long lasting terrain reconnaissance, individual details of a certain area can be studied thoroughly by means of scanned aerial photographs, and also used at the beginning of making a conceptual design. One needn’t point out their application in the area of civil engineering and architecture, especially now, in after war period, for the purpose of ruined and in the war damaged objects, and to make urban plans, as well as for other purposes where visual terrain presentation is necessary (Landek and Kauric, 1998). Maps, and aerial and satellite images are the main data source for GIS. Applications of GIS are rather numerous: national and regional planning, environmental protection, natural resources management, military planning, city administration, land register and land register book, etc

Access restriction

Copyright

fullscreen: International cooperation and technology transfer

Monograph

Chapter

Table of contents

Cite and reuse

Monograph

Chapter

Image

Image fragment

Citation links

Citation recommendation