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Object. Measurements via borehole inclinometers have been actively used in geotechnical monitoring for more than forty years. Due to the high sensitivity of MEMS sensors to external factors, the passport accuracy characteristics of such equipment are significantly underestimated. At the same time, the analysis and interpretation of data obtained by inclinometers measurements are associated with an assessment of these measurements quality. Identifying the random and systematic components of the total error is the k...

With the development of GNSS, one can easily obtain gravity disturbances at almost every point on the Earth’s surface. Thus, the use of gravity disturbance in geoid modeling becomes more appropriate than the use of gravity anomalies that require leveling in the points. For this reason, here is presented the basic theory for the application of radial basis functions for geoid heights modeling and in particular a Hotine-Koch scaling function for calculation with gravity disturbance. The report aims to test the appro...

The calculation of geodetic coordinates ??,??,?? of points on the Earth's surface or in near-Earth space using the spatial geocentric coordinates ??,??,?? obtained by GNSS determinations, has wide application in geodetic practice. The direct problem consisting in determination of ??,??,?? with given ??,??,?? is solved with the established Helmert formulas. The inverse problem (determination of ??,??,?? from ??,??,??) is more complicated, the difficulty is related to the determination of ?? and ??. For the determin...

GNSS technology evolves at a fast pace and, along with it, the number of applications that are based on this technology increases. An important part of the applicability of GNSS technology is in the field of geodesy. In this article we propose to present a GNSS system that is built starting from the U-blox ZED-F9P receiver, integrated on a development board produced by SparkFun that is connected to the Raspberry Pi 4 Model B single-board computer. The Raspberry Pi computer and the development board made by SparkFu...

The data obtained from the monitoring of the dam’s behavior, allow to make the decisions to start the current maintenance works at the best moments of time. They also make it possible to know from early stages possible atypical behavioral phenomena and to take measures accordingly before such phenomena become dangerous for the safety of the construction. One of the ways to monitor constructions is to perform geodetic measurements at different stages and to compare the coordinates obtained in a coordinate reference...

The instrumental accuracy of modern electronic tacheometers allows to measure the elevation difference with the accuracy of geometric leveling. Meanwhile EDM leveling is less time-consuming. The measurement accuracy comparable to the instrumental one is unattainable in real atmosphere due to the vertical refraction. At a distance of 1 km, the vertical refraction effect can reach several tens of centimeters. The decrease in the accuracy of trigonometric leveling due to the influence of vertical refraction limits th...

The paper analyzes normal corrections for the determination of the normal height differences along the First Order Levelling lines in Bulgaria. Normal corrections are calculated in two ways – with measured gravity accelerations and with gravity data from Global Geopotential Models (GGM). The study uses the last contemporary GGMs developed up to 2160-2190 degree and ultra-high resolution GGMPlus model. Calculations for Bouguer anomalies are made by the calculation service in the International Centre for Global Eart...

Along with creating modern infrastructure facilities in Moscow, 9-storey building with a multi-level underground unit is being constructed in the central part of the city. Partial preservation of the structures of existing historical facades of buildings is provided during construction. Buildings, structures of the surrounding development and dense network of underground utilities fall into the zone of construction influence. Taking into account the construction in conditions of dense urban development, near exist...

Surveying stability monitoring of hydraulic structures are an integral part of their safe operation, warning of man-made, environmental emergencies. In most cases, such facilities are not typical objects, and, therefore, blind guidance of regulatory documents cannot provide an opportunity for operational stability control. The problem of designing observation stations in hydraulic structures is extremely relevant in this regard. This article summarizes the experience of conducting systematic high-precision observa...

Bulgaria was integrated with the European Vertical Reference System (EVRS) in 2003 through the connection of the State Levelling Network (SLN) of Bulgaria to the United European Levelling Network (UELN) and Bulgaria's participation in the European Unified Vertical Network Densification Action project. The SLN of the Republic of Bulgaria is connected to the UELN and consequently to the EVRS through the last completed IIIrd realization of the SLN Class I, which was completed in 1984. In 2010, the Ordinance No. 2/30....

Calculation of normal heights and differences from known geopotential numbers and differences in geodetic practice is required when performing independent calculations: for control of levelling network adjustment made with different type heights – normal and geopotential; when using optical clocks technology for geopotential difference determinations; when performing precise engineering and geodetic works. It is well known that between two height types - normal heights and geopotential numbers exists theoretical e...

The objective of this research is to optimize the volume of laboratory tests of physical and mechanical properties of soil. Today, the solution to geomechanical and mining technological problems has the form of functional or statistical relationships, reasoned by the physical parameters of soils (density, moisture, strength properties, acoustic indicators, etc.). The calculations use the average values or estimates of these parameters obtained from statistical processing of multiple laboratory or field test data. ...

The Bulgarian northern Black Sea coast is affected by many landslides. Several geodynamic networks have been built to study landslide processes in the northern Black Sea coast. Landslide research is important, as these phenomena can lead to great material damage. Their destructive impact on buildings, engineering structures and disturbances in the resilience of the earth's crust causes enormous economic, environmental, social and other damage, and often takes human lives. A modern tool for monitoring landslides is...

The provisions of the Geodesy and Cartography Act (in force since 2006) provide for the establishment of a Geo Information System. So far, this Geo Information System has not been created for one reason or another. Given this fact, this publication aims to comment on the main provisions and advantages of the transition to reference to standards in the legislation (primarily Ordinances and Instructions) in the field of Geodesy and Cartography in the country, i.e. reference to one or more standards in place of detai...

Globally, modern crustal movements are being studied as a priority, a large number of projects are being developed and significant funds are being allocated for the development of research in this field of science. Due to the social importance of the problem, the need to obtain geodetic data on the current activity of the earth's crust is realized. This article examines the study of the temporal movements of the earth's crust and the accumulated stresses in a geologically and seismically active region with the pre...

This publication aims to offer a generalized approach in describing a conceptual mod?l based on the ISO Conceptual Schema Modelling Facility Schema architecture and so-called Systems approach, based on General Systems Theory to establish interoperability at creation, acceptance, maintenance and renewal of the State Levelling Network I and II Order. The basis for proposing this generalized approach is the new Instruction for the establishment and maintenance of the State Levelling Network. This Instruction has been...

QDaedalus systems are currently used for astronomical observations to obtain astrogeodetic vertical deflections (VDs). Astronomical observations cannot be made under the same conditions as geodetic observations (e.g., GNSS), because meteorological factors (e.g., cloud cover during observation, high humidity, fog, etc.) and timing of the observations may directly affect the observed benchmarks, particularly regarding precision and accuracy determinations of the VD components observed with the QDaedalus system. For ...

The region of southwest Bulgaria is characterized by a large number of fault structures, and the presence of tectonic and seismic activity, thus predetermines the development of dangerous geodynamic processes. This article discusses the estimates of modern movements of the earth's crust obtained from periodic geodetic measurements. They describe the total effect of fast and slow horizontal and vertical movements. Obtaining such estimates, on the order of mm/y, requires determining the coordinates of the points of ...

During the process of drilling wells with a complex spatial profile, it is necessary to obtain timely information about technological processes in order to control them. This issue is relevant for the oil and gas industry, since the number of works of increased complexity is constantly growing. This article discusses the technique of vertical tomography in control problems during directional well drilling. The object of control in this case is the technological equipment, the well and the surrounding soil. The art...