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The cartographical projections are the representations of the terrestrial surface on different projection plans that can bew cylinder and con. The important problem for representing these projections is to reduce the characteristic deformations of each projections. The problem that is analyzed refers to an assessment of the points transpositions from a sphere surface on a plane in conditions of maximum efficiency.

Criteria for assessment of geodetic networks, measurements and digital territory models are discussed in the paper. Methods for accuracy verification and actuality verification of planned geodetic networks with local use, cadastral plans and maps situation and their digital models are shown with examples. Technology for geodetic networks and measurements accuracy assessment is offered.

The subjects of deformation monitoring are either natural objects such as ground deformation due to mining exploitation, withdrawal of oil or underground water, active tectonic plate boundaries, glacier movements etc., or the man-made objects such as dams, bridges, tunnels and other complex engineering structures. The results of deformation monitoring are directly relevant to the safety of human life and environment protection. The bridges are very important subjects in the field of infrastructure management. Stab...

The basic geodesic activities in the preparation of the Project “Reconstruction and Electrification of the Railway Line Plovdiv – Svilengrad – Greek/Turkish Border” have been described. The problems in the development of the working geodesic base, creation of a three-dimensional model, cadastral map, and the detailed structural layouts of the territory in question have been discussed. Specific attention has been paid to the procedures in changing the purpose of the agricultural and forestry territories and...

Existing conditions, aims and tasks of investigation and geodetic methods is described. Obtained displacements for the period 1966-2004 are analyzed. Corresponding conclusions are drawn.

In this paper it is presented the basically geodetic methods for defining and following of land movements and land slide. The classic geodetic method anticipates defining of horizontal and vertical deformation in some points buried in the body of land slide. The deformation is defining with precision angular and linear measurements and with precision leveling from stabile points of primary geodetic nets (the microtrigonometric and the level net). The terrestrial photogrametry is used in the defining deformation of...

Landslide Hazard Zonation (LHZ) is a method to evaluate the risk where there is the potential for landslides. Therefore, many terrain factors affecting the landslides have been exposed firstly. The factors contributing to the hazard in an area can usually be identified, results of the investigations frequently being presented as a landslide hazard zonation map indicating zones of similar risk of the occurrence of a landslide. North railway track is one of the areas susceptible to landslides in Iran, consist of sev...

Landslides have a large quantity of the natural disasters world-wide, this trend will increase in the future due to increased urbanization and development. The creation of maps of susceptibility, danger and risk is very important for engineering geologists, geomorphologists and city planners. Although several techniques are available for landslide risk investigation, reliable susceptibility mapping of landslides is very difficult due to their complex nature. Techniques for susceptibility mapping such as; determini...

A review and analysis of the different methods used for processing of geodetic data, depending on the applications is made. Here is considered Least - squares estimation method, dispersion analysis, spectral analysis, and filtering and is made an analysis of their effectiveness in using for different geodetic problems (applications). We made suggestions for methods using in common processing of different types of data.

In this work in terms of the ideas of the zone of inelastic deformations generated around stress concentrators in heterogeneous rock mass as a quasi-plastic block medium having a microstructure, rigorous criteria of rock mass stability are obtained that naturally take into account mining-geological and geomechanical conditions. Theoretical ideas added to the problems of underground structure stability permitted to provide an explanation for paradoxical, in the view of classical representations, numerous cases of m...

A modification of the conventional adjustment model is proposed. Like this, the velocity of the drift is introduced as an additional unknown quantity. An argument about the priorities of the suggested approach, in comparison with the used at present methods for gravimetric measurements processing is done. The possibilities which the new adjustment model provide for an optimization of the whole measurements program in a gravimetric network are analyzed.

Mass-produced digital photographic cameras are not designed for measurement purposes. Their resolution, measured in degrees is 1-2’ and is one step behind photogrammetric cameras. The main purposes of photogrammetric processing of amateur digital photographs are determination of the elements of internal orientation and uncovering the deformation of the acquired images. Three different ways of determination the elements of internal orientation are analyzed. The theoretical aspects of the mathematical methods for ...

This paper presents the results of an assessment of the earthquake hazard for the Qom province, based on seismotectonic conditions, regional earthquake data and seismicity analyses. The active faults and potential seismic sources of the region are identified and illustrated in a seismotectonic map. A model of earthquake sources has been prepared. The appropriate acceleration attenuation laws are selected and earthquake hazard analysis has been done for the province using an analysis point interval scale of 0.1*0.1...

At present one has quite a good knowledge of lithospheric plate movement that occurs along such large living fractures as San Andreas in California, North Anatolian in Turkey and others. At the rest of the earth’s territory rock mass for the most part seem to be a static and motionless medium. However, as investigations show, even at small rock mass areas deformation processes of different period and amplitude take place. Such processes that occur in the earth’s crust are connected with a serious risk for obje...

Development of the engineering infrastructure pays a bigger attention on the utilizing of new construction fields. Significant risks are concealed in the construction of the buildings, structures, roads and railroads on the grounds, which had not been an object of the engineering and geological researches. It is possible to arise disadvantageous effects for the construction. Karst fields in Bulgaria hide many potential dangers if engineering and geological researches are insufficient. The object of the present wor...

It was considered the physical bases of tides. The accent is on the influence of tides over gravimetric measurements. It was accent on the Moon too as a basic planet made tides. It was shown an entire and complete technology for computation of tidal correction and it is applied for real gravimetric measurements. Here was made analysis and conclusions with practical purpose.

The ionosphere is the upper part of the Earth atmosphere, starting at an altitude of about 50 km. It consists of free electrons and ions, mainly generated through solar radiation. GPS observations are delayed within the ionosphere, since it is a dispersive medium for electromagnetic waves. The range error caused by the ionosphere at the GPS operation frequency L1 can reach a few tens of meters. This effect is as a first approximation proportional to the so-called Slant Total Electron Content (STEC) along the ray p...