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In the old coordinate system, church belfries often served as reference points in detail surveying. Consequently, their coordinates were regularly maintained in the geodetic databases of the old coordinate system. Their usability was significantly reduced by the establishment of the new coordinate system along with the use of satellite-based positioning methods and transformation models. Considering that the number of ground points of the old trigonometric geodetic networks decreases due to reconstruction, today they have gained practical value. Most of them were preserved in their original condition, which enables a continuous transition from the old to the new coordinate system as well as the reconstruction of the old situation on the basis of the old coordinate system data. They can be used in the determination of the transformation parameters of the detail or for the quality evaluation of the state transformation model. For this, their coordinates should be determined in the new coordinate system. The present article describes the determination of positions of five church belfries in the new coordinate system D96/TM, which are located in the southwestern part of Ljubljana. The procedure combines the determination of the geodetic network datum by GNSS, the inclusion of terrestrial measurements and free-network least squares adjustment and further use of the S-transformation. Further comparison of coordinates, acquired in different ways, shows some centimetre differences in each coordinate component for the given sample of church belfries. Therefore, for the sample under consideration, we can conclude that the Slovenian triangle-based transformation model effectively describes the transformation between the old and the new coordinate systems in the area under consideration.

Every man-made structure creates certain risks — dams are no exception. Most failures in man-made structures that have occurred could have been avoided if the structures’ behaviour had been inspected, monitored, and analyzed continuously, and if proper corrective measures had been taken in a timely fashion. The DSI (The General Directorate of State Hydraulic Works), which is the institution responsible for dam safety, has long used surveying methods to measure the displacements of geodetic points as a part of dam monitoring policy. In this study, we focus on the dam's mechanical behaviour throughout a time period of more than 10 years. These study results have been derived from a separate, ongoing project that has monitored deformation on the Ataturk Dam and is now determining the water level of the reservoir. The project results show that although the dam body has become more stable and the water load behind the dam has increased, the rate of displacement of the dam has declined significantly. From these results, it can be seen that the reservoir water level can be increased evenly over time and that 542 m is the maximum water level of the dam's reservoir.

In the context of natural phenomena (earthquakes, floods, landslides etc.) bring economical and social prejudices year by year, watching on them and taking decisions becomes mandatory for reducing the material and human lives loss. Making hazard maps represents a tool used on wide global scale but also particularly in our country. This paper work has the purpose to reveal the interests of certain authors related to the usage of the new technologies of terrestrial measurements (GPS technologies, photogrammetry, cartography and of remote sensing) in order to make these hazard maps.

The article focuses on the geodetic monitoring of the Rabenov landslide territory. The monitored slope is situated in the landscape deteriorated by mining activity in North Bohemia, West of Usti nad Labem, in Chabařovice, a reclaimed brown coal pit. The article presents a general description of the application and accuracy of geodetic methods used to measure on the movement of material in landslides. Also, the history, the problems and the plans for reclamation of the monitored territory are briefly mentioned. The text concentrates on the description of the network of three observed points which are formed by geotechnical instrumentations and on the description of a terrestrial and GNSS measurement in the network of monitored points. The assessment methods and the results from the eight-year phased monitoring process are also discussed. Different methods were tested during the phases. For terrestrial measurements, standard deviations of about 2 mm in position were made and for GNSS standard deviations of about 14 mm. Surveys in a local grid showed that there were continuous movements of observed station points of about 10 mm per year. The paper also discusses the use and assessment of digital terrain models in zones with on-going artificial as well as natural changes. Models indicate elevation changes of about 2–6 m and movement of about 10,000–100,000 m3 of material.

Every man-made structure creates certain risks — dams are no exception. Most failures in man-made structures that have occurred could have been avoided if the structures' behaviour had been inspected, monitored, and analyzed continuously, and if proper corrective measures had been taken in a timely fashion. The DSI (The General Directorate of State Hydraulic Works), which is the institution responsible for dam safety, has long used surveying methods to measure the displacements of geodetic points as a part of dam monitoring policy. In this study, we focus on the dam's mechanical behaviour throughout a time period of more than 10 years. These study results have been derived from a separate, ongoing project that has monitored deformation on the Ataturk Dam and is now determining the water level of the reservoir. The project results show that although the dam body has become more stable and the water load behind the dam has increased, the rate of displacement of the dam has declined significantly. From these results, it can be seen that the reservoir water level can be increased evenly over time and that 542 m is the maximum water level of the dam's reservoir. [ABSTRACT FROM AUTHOR]

Abstract: In a context of global change and increasing anthropic pressure on the environment, monitoring the Earth system and its evolution has become one of the key missions of geosciences. Geodesy is the geoscience that measures the geometric shape of the Earth, its orientation in space, and gravity field. Time‐variable gravity, because of its high accuracy, can be used to build an enhanced picture and understanding of the changing Earth. Ground‐based gravimetry can determine the change in gravity related to the Earth rotation fluctuation, to celestial body and Earth attractions, to the mass in the direct vicinity of the instruments, and to vertical displacement of the instrument itself on the ground. In this paper, we review the geophysical questions that can be addressed by ground gravimeters used to monitor time‐variable gravity. This is done in relation to the instrumental characteristics, noise sources, and good practices. We also discuss the next challenges to be met by ground gravimetry, the place that terrestrial gravimetry should hold in the Earth observation system, and perspectives and recommendations about the future of ground gravity instrumentation. [ABSTRACT FROM AUTHOR]

3D laser scanning is very useful method to reach digital terrain model as the common output of map making. The paper deals with an application of 3D laser scanning in railway track measurements, which belong to the field of engineering surveying. Experimental measurements were carried out on the ballast-less railway construction with the purpose to determine its track geometry by the combination of terrestrial and laser scanning methods. Measurements were carried out in conformity with conditions involved in corresponding technical standards. Surveyors used a variety of firmware, CAD and mathematical software for laser scanning processing to reach the expected outputs in adequate volume, accuracy and reliability.

An optimal stabilisation of geodetic points is undeniably an important factor when determining displacements. According to the size of the anticipated displacements a proper stabilisation accuracy must be provided. Traditional ways of stabilisation are discussed as well as a new method for measuring tectonic movement is proposed. Accordingly, a quality analysis of the new stabilisation method used in the precision micro-network of the town of Libna in the vicinity of Krško is given.

The article focuses on the geodetic monitoring of the Rabenov landslide territory. The monitored slope is situated in the landscape deteriorated by mining activity in North Bohemia, West of Ústí nad Labem, in Chabařovice, a reclaimed brown coal pit. The article presents a general description of the application and accuracy of geodetic methods used to measure on the movement of material in landslides. Also, the history, the problems and the plans for reclamation of the monitored territory are briefly mentioned. The text concentrates on the description of the network of three observed points which are formed by geotechnical instrumentations and on the description of a terrestrial and GNSS measurement in the network of monitored points. The assessment methods and the results from the eight-year phased monitoring process are also discussed. Different methods were tested during the phases. For terrestrial measurements, standard deviations of about 2 mm in position were made and for GNSS standard deviations of about 14 mm. Surveys in a local grid showed that there were continuous movements of observed station points of about 10 mm per year. The paper also discusses the use and assessment of digital terrain models in zones with on-going artificial as well as natural changes. Models indicate elevation changes of about 2-6 m and movement of about 10,000-100,000 m3 of material. [ABSTRACT FROM AUTHOR]

Compelling observational evidence is given that metric expansion of space occurs at all scales of distance in the universe, in contradiction to orthodox expectation. This includes recent astronomical observations and the results of recent terrestrial experiments made possible by improvements in the sensitivity and stability of measuring instruments and techniques. Consequences of universal metric expansion on terrestrial measurements include an increase with time of the apparent speed of light, and an apparent speed of high-energy particles greater than the speed of light, but with both not exceeding light speed through the expanding space. It is shown that these effects might be directly observed and measured with existing apparatus. [ABSTRACT FROM AUTHOR]

Abstract: Gamma-ray measurements in terrestrial/environmental samples require the use of high efficient detectors because of the low level of the radionuclide activity concentrations in the samples; thus scintillators are suitable for this purpose. Two scintillation detectors were studied in this work; CsI(Tl) and NaI(Tl) with identical size for measurement of terrestrial samples for performance study. This work describes a Monte Carlo method for making the full-energy efficiency calibration curves for both detectors using gamma-ray energies associated with the decay of naturally occurring radionuclides 137Cs (661keV), 40K (1460keV), 238U (214Bi, 1764keV) and 232Th (208Tl, 2614keV), which are found in terrestrial samples. The magnitude of the coincidence summing effect occurring for the 2614keV emission of 208Tl is assessed by simulation. The method provides an efficient tool to make the full-energy efficiency calibration curve for scintillation detectors for any samples geometry and volume in order to determine accurate activity concentrations in terrestrial samples. [Copyright &y& Elsevier]