Alireza Owsati (Translator)
Volume 5, Issue 17 , May 1996, , Pages 42-61
Abstract
Water resources forms part of hydrology that is linked to hydrological characteristics that are clearly variable in time and space. The information contained in the archive basically provides cheaper information sources and this issue should be considered before new measures are initiated. For small-scale ...
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Water resources forms part of hydrology that is linked to hydrological characteristics that are clearly variable in time and space. The information contained in the archive basically provides cheaper information sources and this issue should be considered before new measures are initiated. For small-scale studies, measurements with ground-based equipment provide a very good solution for engineering issues. Ground-based devices are able to acquire highly precise data over a range of time frequencies and are able to operate under any atmospheric conditions. Their major fault is that they perform the measurement only for one point that represents the whole. In order to compensate for this defect, the number of ground-based measurements for the point, which is determined by the time needed to install the equipment, manpower for installation, process and analysis of the data, and most importantly the cost of purchase and operation, can be increased.
Remote sensing methods are able to measure surface level variability, which can never be measured from the ground surface, and include the alignment of ground-based measurements precision. Ground-based measurement control, such as a spectral reflector, should often accompany remote sensing data acquisition. Refer to Figure 1.
Integrating a limited number of ground-based measurements can prevent great waste of the staff’s time in the desert. In this part, remote sensing performance is discussed in terms of behavioral evaluation of the hydrological changes that are of importance for civil engineers.
Alireza Owsati (Translation)
Volume 4, Issue 13 , May 1995, , Pages 44-59
Abstract
In this regard, NASA's projects are currently conducted using Itek cameras with a large 26 × 23 cm frame and enjoying a lens with a 30-cm focal length (F=30) (1979 Doyle). These cameras are directly installed on the outer part of the pallet, which is set at the place of shuttle’s load. In ...
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In this regard, NASA's projects are currently conducted using Itek cameras with a large 26 × 23 cm frame and enjoying a lens with a 30-cm focal length (F=30) (1979 Doyle). These cameras are directly installed on the outer part of the pallet, which is set at the place of shuttle’s load. In this regard, refer to Figures 16-19. See the specifications of these two cameras in Table 3. The ground scale and resolution of photography by these two cameras are very easy to capture; the main features of these cameras can be seen in their perspective dimensions. The Itek LFC cameras are, in fact, an idea within the programs of developing American military surveying and identifying cameras with a 46x23cm frame. These cameras are capable of acting in both cross-tracking and along-tracking manners, and the case enjoying lens with higher geometric quality is utilized. In the case of a lens with a focal length of F = 30 centimeter in these cameras, an open angular cover of 74o with a ratio of height to wide image of 0.6 (60% coverage) in the direction of the path is obtained.
