No abstract

Open pit coal mining affects surrounding populated areas, resulting in terrain surface deformation. Surface deformation should be monitored as often as possible to control deformations and prevent potential incidents. This paper analyzes time series deformation estimated from the Sentinel-1 satellite images using the Persistent Scatterer Interferometry method to monitor subsidence rates caused by open pit mining activities. It is possible to measure deformations using classical geodetic methods, but those are rarely used in practice because they are time-consuming and expensive for application in large areas. Using the open access radar images from the Sentinel-1 mission, 513 images from the repository were downloaded between October 2016 and the end of December 2020. We present the processing steps in detail in order to establish a workflow for the automated processing of vertical displacement estimation using open source tools; a total of 402 images were processed: 215 images belonged to the ascending satellite orbit, 187 images belonged to the descending orbit, and 111 images were rejected because of adverse weather conditions. The PS InSAR technique has never been used for the mines of the Republic of Serbia or for land surveying practices related to deformation monitoring. The results based on the Sentinel-1 images were compared with results from geodetic leveling and with neotectonic uplift trends. The trend lines of vertical displacement obtained from PS and corresponding leveling are significantly similar (a Pearson correlation of 85% with a p-value of 0.015). The final evaluation reported results of vertical displacements at the leveling benchmark of −3.4 mm/year with the PS InSAR method and −2.7 mm/year with the leveling method. A comparison of the PS vertical displacements with a settlement model fits reasonably, suggesting that the measurements are valid. As four years of PS time series data is insufficient to establish undisputable conclusions on the neotectonics uplift, extending the time series (covering at least a decade) implies that this approach will become attractive in future neotectonic uplift trend estimations. This study illustrates not only the ability of Sentinel-1 data in mapping vertical deformations, but the obtained results could also be used for geohazard monitoring and land monitoring in general for the area of interest.

No abstract

Abstract:The topographic plane of the Earth has irregular shape, and for the purpose of mathematical defining, it is to be approximated by rotational ellipsoid. As local geodetic datum, rotational ellipsoids of various sizes are used in the world. More widely usage of the GPS while performing surveying tasks has resulted in the need to define global geodetic datum in order to obtain the best approximation the entire Earth. For this purpose, geocentric rotational ellipsoid WGS84 was defined and the results of the GPS measurements are shown in relation to it. By applying the appropriate equations, the ellipsoidal coordinates are being transformed from WGS84 into the coordinates on the local rotational ellipsoid, i.e. on the view plane. The paper shows User Defined Function created for Excel, by which the coordinates in the territory of Belgrade are being transformed from WGS84 of rotational ellipsoid into the Gauss-Krüger projection plane. Key words: WGS84, Bessel ellipsoid, transformation of coordinatesApstrakt: Topografska površ Zemlje je nepravilnog oblika, a u cilju matematičkog definisanja, aproksimira se obrtnim elipsoidom. Kao lokalni geodetski datumi u svetu se koriste obrtni elipsoidi različitih dimenzija. Sve masovnija upotreba GPS-a pri obavljanju geodetskih radova uslovila je potrebu definisanja globalnog geodetskog datuma kojim će se najbolje aproksimirati cela Zemlja. U tom cilju, definisan je geocentrični obrtni elipsoid WGS84 i rezultati GPS merenja se prikazuju u odnosu na njega. Primenom odgovarajućih jednačina, elipsoidne koordinate iz WGS84 transformišu se u koordinate na lokalnom obrtnom elipsoidu, odnosno projekcionoj ravni. U radu je prikazana User Defined Function kreirana za Excel, kojom se na teritoriji Beograda transformišu koordinate sa WGS84 obrtnog elipsoida u ravan Gaus-Krigerove projekcije.

Abstract:The Danish astronomer Peter Andreas Hansen, who also worked on theoretical geodesy, provided an original solution for solving the geodetic quadrilateral in which the four angles and the length of one side are known. This procedure, identified in scientific literature as Hansen's problem, has been applied in geodesy but significantly more so when solving various problems related to mining measurements in underground exploitation. Nonetheless, the literature does not cover the determining of the standard deviation of the coordinates of unknown points which are established using Hansen's method. In this paper then, equations are derived to calculate the standard deviation of the coordinates determined by the above mentioned procedure.Key words: geodetic quadrilateral, Hansen's problem, standard deviation Apstrakt: Danski astronom Peter Andreas Hansen, koji se bavio i teorijskom geodezijom dao je originalno rešenje za rešavanje geodetskog četvorougla u kome su poznata četiri ugla i dužina jedne strane. Ovaj postupak koji se u stručnoj literaturi naziva "Hanzenov problem" našao je primenu u Geodeziji, ali znatno više u rešavanju različitih zadataka iz oblasti Rudarskih merenja koji se javljaju pri podzemnoj eksploataciji. Međutim, ono što u literaturi nije obrađeno predstavlja određivanje standardnih odstupanja koordinata nepoznatih tačaka do kojih se dolazi primenom Hanzenovog postupka. U ovom radu izvedene su jednačine za računanje standardnih odstupanja koordinata određenih navedenim postupkom.

Abstract:The development of the crosscut from the aspect of mine surveying is a specific task, since there is no possibility for an independent control of its construction duringthe development. This is primarily related to the long crosscuts where the deviations of the designed direction of crosscut would have significant consequences on safety and technological activities in the mine shaft. In order to avoid errors, it is necessary to perform the preceding analysis of the crosscut accuracy, where the overall standard deviation of the crosscut is calculated. This value must be smaller than the given allowed deviation. The paper presents an a priori evaluation of the accuracy of the crosscut to be developed in the brown coal mine "Soko" for the purpose of ventilating the opening rooms of the eastern part of the deposit. Key words: mine surveying, crosscut, apriori accuracy evaluationApstrakt: Izrada proboja sa aspekta rudarskih merenja je težak i odgovoran posao. Ovo se pre svega odnosi na izradu dužih proboja, s obzirom da u toku njegove izrade ne postoji mogućnost nezavisne kontrole njegove realizacije. Zato je u ovakvim slučajevima neophodna prethodna analiza tačnosti proboja, gde se na osnovu svih potrebnih elemenata, računa ukupno standardno odstupanje proboja koje mora da bude manje od zadatog dozvoljenog odstupanja. U radu je prikazana a priori ocena tačnosti proboja koji treba da se realizuje u rudniku mrkog uglja ,,Soko" za potrebe ventilacije prostorija otvaranja istočnog dela ležišta.

Transformation between ellipsoids also called datum transformation implies coordinate conversion from one ellipsoid to another ellipsoid, most frequently to be done by Helmert seven-parameter transformation. Transformation parameters involve three rotation, three translation and scale factor and they can be calculated using reference points which are known before and after transformation. Transformation parameters can be obtained with appropriate measurements and in accoradance with measurement uncertainties, they are produce errors of transformed coordinates. This paper describes standard errors of transformed coordinates using Helmert seven-parameter transformation, when switching from ellipsoid WGS84 to Bessel ellipsoid.

This paper presents a review of the advantages of application of JKSimBlast 2DFace software in design phase of underground premises. The aim of this research was to show possibilities of the software and possibility of its application in design of underground premises with suggestions for further work. A model of a drift "TIP 5" was developed and analysed in the software to show all the possibilities of the application of software in underground construction. Further work would require a detailed field work to gather input data required for more detail analysis of the effects of blasting in the software itself, as well as validation of the results given by software on the field.