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In order to evaluate the accuracy of the local geodetic network of Jurmala City, in research, comparison of forty-seven selected polygonometry network point coordinates with the obtained data was made by performing measurements by real time cinematic (RTK) method in LatPos base station system. Points were chosen so in order to cover evenly the entire territory of the city. At present, gradual renewal and improvement of the local geodetic network takes place in Jurmala. The linear discrepancy of coordinates obtained in measurements varies from 0.016 m to 0.259 m, mean linear discrepancy in the measured points is fixed 0.110 m. Discrepancy of plane coordinates in different regions of Jurmala is not even. It is rather even within approximate boundaries of the determined regions, this is indicated by different directions of offset vectors, which in eastern part of the city are pointed mainly in NW direction, in central part directions are pointed in W direction, but in the western part of the city pointed in NE direction. Concerning heights, only for 3 of measured points discrepancy exceeds 0.05 m error and there are no connection concerning some specific region. 15% of the measured points of the local geodetic network are with appropriate accuracy of plane coordinates. The linear discrepancy of plane coordinates for points of the local geodetic network, which are measured by RTK method and compared with data from the improved network is 0.024 (m), which indicates the high accuracy of RTK method in measurement data. In Jurmala City, obtaining of data by GNNS data receivers is encumbered by large density of trees. Therefore the local geodetic network in city has very important role in order to ensure performance of geodetic measurements of high quality in the territory of the city. Aim of the research is to evaluate the accuracy of the local geodetic network of Jurmala City. The following tasks have been set for achieving the aim: research of the given problem, visit of the local geodetic network points, performing control measurements, data processing and analysis. [ABSTRACT FROM AUTHOR]

Continuous assessment of the displacement of a high-rise building enables verification that it meets the structural assumptions calculated in the project, and provides additional useful feedback for structural engineers. Unexpected structural responses during the phases of construction, or once the building is in use, can help detect current and future problems, as well as provide cost savings. Furthermore, it contributes to an improved risk management for natural phenomena and can be used to verify the stability of the structure, providing an additional safety layer for the building. The technological improvement in global navigation satellite system (GNSS) techniques has allowed significant advancements of Gaussian methodologies applied to control the dynamics of building structures in real time, especially for calculating, controlling, and interpreting satellite survey measurements, based on Gaussian analysis and least squares adjustment. The real-time monitoring system works by implementing a local geodetic network with GNSS technology on the structure to be monitored. Algorithms are then applied that improve the compensated network solution, and this is integrated into original software. The system allows us to achieve a high level of safety and effective risk management in real time, as a unique mathematical model that allows GNSS position errors to be reduced is designed for each building. In the case of Torre Espacio, the overall mathematical adjustment model reduces the maximum error by 40%. The system has been installed on a high-rise building, Torre Espacio, in Madrid, Spain, and is fully operational. [ABSTRACT FROM AUTHOR]

Při vývoji geodetického řešení a plnění požadavků a potřeb na dokončení stavebních úkolů a dosažení cílů jsme často konfrontováni s požadavkem na rozšíření prostoru či vyšší koncentraci bodů v určitém místní bodovém poli. Důraz je kladen na nutnost vhodného doplnění dané oblasti novými geodetickými body v potřebné kvalitě, tj. s přijatelnou trojrozměrnou přesností z hlediska jejich komplexního využití pro stavební a kontrolní účely. Tato práce obsahuje stručný přehled o zřizování nových dodatečných geodetických bodů a zajištění jejich kvality, která by byla kompatibilní s kvalitou stávajících bodů v této oblasti, aby bylo používání obou skupin bodů v příslušném místním bodovém poli homogenní

For processing the results of local geodetic network (LGN) measurement with possible erroneous values and coordinates:d (slope distances between the points), ω (horizontal angles), z (zenith distances). CDB = [X ,Y]DB (coordinates of the datumpoints), CU0B = [X 0 ,Y 0 ]UB (coordinates of approximately determined points) and detecting the errors it is appropriate to usea technique that will be further demonstrated in a real situation of the trilateration LGN (fig. 1) with a massive contaminationof the simulated errors in the measured elements and numerically determined values.

In the process of the foundation, expansion, modification LGN (free or fixed), based on its convenient measuring it defines coordinatepoints and others parameters of networks. The check of measurings and calculations solves by using convenient matrix relations in thenegation form. Their failure points out the incorrect measurement and calculations in the LGN.

When a new Local Geodetic Network (LGN) should be established, some “old” geodetic points with coordinates [XY] fromthe present point field are used and contemporaneously some necessary “new” points are established in the area of LGN. Theirapproximate coordinates [X°Y°] are determined using competent measurements and computations.If the coordinate determinations of new points are correct and the coordinates of old points are without points decompabilities,the new LGN with all properties can be correctly determined using a convenient adjustment.If new network–points are not correctly determined (some distances and angles badly measured, other injurious influences),the adjustment results are not acceptable. (large residuals V, large coordinate standard deviations ˆ, ˆ, X Y s s etc.). In such falls thereis necessary to search for causes of the bad results in the network-adjustment. Occurrence of such a situation can be found in big valuesof some quantities oi i i dL = L − L of the vector dL ( i L - measured quantities as distances, angles, …; oiL - their approximative values.The wrong (large) i dL will ambiguously identify in the adjustment the distances, angles and the corresponding approximativecoordinates, which are unacceptable.Such situations are characteristic for:• Least Squares Adjustment (LSA),• Iteratively Reweighted Robust LSA (IRRLSA),as they are applicable for identification of wrong results in the adjustments

The quality of Local Geodetic Network (LGN) for technical and scientific purposes is very important from many points of view. These netsrequire compatible points (given and new ones), measurements among points without blunders and reliable determination of approximatecoordinates for the new (to be established) points. If some from the 3 mentioned requirements is not fulfilled for the network computation,the various results from the net adjustments are defective and unusable. In the present treatise, all requirements for faultless measurements areintroduced and demonstrated in adjustments of a trilateral net using the standard, constrained adjustment (GMM of full rank with minimumconstraints) and the interactively reweighed Least-Square Robust Adjustment. From analyses of their solutions can be by convenient introducedmethods determined and identificy all errors in the net measurements.

GNU project Gama for adjustment of geodetic networks is presented. Numerical solution of Least Squares Adjustment in the project is based on Singular Value Decomposition (SVD) and General Orthogonalization Algorithm (GSO). Both algorithms enable solution of singular systems resulting from adjustment of free geodetic networks.