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A specific application of the Method of the finite elements is proposed. The approach is based on the theory about the rheological segmentation of the Earth crust. Different practical various of the proposed method are considered

Theoretical and experimental investigations have been made to study the polar motion based on the IERS (International Earth Rotation Service) solution. A set of 9 mathematical models is proposed to examine the time series of polar motion. We have proved by statistical tests that the ARMA (2,1) model is the “best” one of the proposed set of competing models. Estimates have been obtained of the spectral characteristics by investigating the cyclic polar motion variations. Criteria are applied to assess the adequa...

Modern technology in the production of geodetic instruments and accessories needed for measuring basic quantities (distance and angle) has reached high level. In the filed of geometric levelling, colour layers are put on invar tapes very precisely with measuring uncertainty of 10–50 $\mu$m. These tapes present working scale on invar levelling staves. Using modern precise level (optical of digital) one can read the smallest detail on invar levelling staff with measuring uncertainty of 0.01 mm. Hence, it is obviou...

NAVITEQ establishes the first nationwide GNSS network in Bulgaria. It is a private project that offers an inexpensive way of precise positioning by transmitting correction data. The main purpose is to provide services to GNSS users that need centimeter and sub-centimeter accuracy. NAVITEQ provides three types of services called Naviteq Post Processing, Naviteq VRS and Naviteq PreciseRTK. There is another service in real time mode that is under development. The NAVITEQ reference stations positions are determined in...

Analytical model of the stress-deformed state of the rock mass in production mining is proposed. In comparison with conventional ones, the model takes into account the depth of coal extraction, thickness seam and the existence of the total zone of mining subsidence displacement. As is shown by calculations, effect of said factors results in complete reconsideration of the stress-strain state pattern of the rock mass and may serve as the basis for the development of mining subsidence displacement theory.

The contemporary construction on the territory of Sofia requires more and more responsible execution of the geological researches. The drilling of deep construction pits, as well as the construction of high-rise buildings (with more than 100 m height), are connected with serious problems, especially in the anti earthquake security insurance. One of the important questions which were raised in the construction of Metrostation 7 in the Sofia’s centre, as well as in the designing of Europa Center, having 180 m offi...

Rockfalls are natural process of cliff and hillside erosion, can be simulated by the computer programs. They consist of large rock fragments from a cliff, or boulders from a slope that bounce, roll, and slide down a hillside and come to rest in a “runout” zone at or near its base. Rockfalls are a major hazard in rock cuts for highways and railways, and in mountainous terrain. Rockfalls are generally initiated by some climatic or biological event that causes a change in the forces acting on a rock. These events...

Interferometric analysis of Synthetic Aperture Radar (InSAR) on the Advanced Land Observation Satellite (ALOS PALSAR) shows the spatial pattern of the deformation associated with the magnitude 6.8 Niigataken Chuetsu-oki Earthquake of 26th July, 2007. It reveals not only the large deformation near the source area of the earthquake, but also the local zonal uplift area with 1.5km-wide and 15km-long band along the anticline axis of active fold, on Nishiyama Hill at 15km east of the earthquake epicenter. We consider i...

GPS RTK method has never achieved millimetre vertical accuracy. For the most common geodetic tasks such as surveying, staking out and monitoring, GPS RTK method in many cases has been limited by its measuring accuracy. Before the appearance of the new Topcon Lazer ZoneTM technology, we were able to achieve centimetre vertical accuracy (from 1 to 3 centimetre) using GPS RTK systems. Combining Topcon Lazer ZoneTM technology and Topcon GPS RTK HiPer Pro system accuracy of height determination can be increased to a mi...

Tunnels are the objects of road infrastructure which construction requires very complex, demanding, and responsible geodetic tasks. In the tunnelling, at first it is necessary to establish high quality geodetic control that serves as the base for the transfer of the planned tunnel axis in horizontal and vertical directions, as well as the base for all geodetic measurements realised before, during and after tunnel construction. The basic quantity for the planning the completely measuring concept in the tunnelling i...