Academic literature on the topic 'Local geodetic networks'

Local geodetic network is very important in harmonic development of city territory. On the base of the local geodetic network, cadastral and topographic surveying works, engineering geodetic works and executive measurements of newly built buildings and engineering networks are carried out. In the territory of Riga, the local geodetic network was started to create in 1880, and in the course of time, as the city expanded, necessity to have wider reference network emerged. In 2005, in the territory of Latvia, network of continuously working base stations LatPos was launched, which ensured completely new trends in execution of measurements and accuracy reached. One year later, base station network EUPOS-RIGA was launched in the territory of Riga. It can be regarded as consistent part of Riga local geodetic network. The purpose of the research was to state, what are differences between historically used coordinates of points of the local geodetic network, and coordinates that are determined by use of real time corrections of LatPos and EUPOS-RIGA base station network. Measurements were made in the territory of Riga in period from December 2016 until April 2017. In the framework of the research, 61 point of the local geodetic network was inspected and in 38 cases GNSS observations in RTK mode were completed. In the research, catalogues of coordinates of polygonometry points of sixties and eighties were used in order to compare what differences of coordinates existed historically. The main conclusion drawn during the research – historical points of the local geodetic network shall not be used for surveying works of any kind before improvement of them and before they comply with requirements of normative acts.

The implementation of local geodetic networks for georeferencing of rural properties has become a requirement after publication of the Georeferencing Technical Standard by INCRA. According to this standard, the maximum distance of baselines to GNSS L1 receivers is of 20 km. Besides the length of the baseline, the geometry and the number of geodetic control stations are other factors to be considered in the implementation of geodetic networks. Thus, this research aimed to examine the influence of baseline lengths higher than the regulated limit of 20 km, the geometry and the number of control stations on quality of local geodetic networks for georeferencing, and also to demonstrate the importance of using specific tests to evaluate the solution of ambiguities and on the quality of the adjustment. The results indicated that the increasing number of control stations has improved the quality of the network, the geometry has not influenced on the quality and the baseline length has influenced on the quality; however, lengths higher than 20 km has not interrupted the implementation, with GPS L1 receiver, of the local geodetic network for the purpose of georeferencing. Also, the use of different statistical tests, both for the evaluation of the resolution of ambiguities and for the adjustment, have enabled greater clearness in analyzing the results, which allow that unsuitable observations may be eliminated.

Increasing the speed of trains along railroad tracks and the development of satellite geodetic technologies put forward new requirements for the production of the engineering survey at the rail transport facilities. Ensuring the safety of high-speed traffic is directly related to the accuracy of determining the coordinates and heights of the reference geodetic networks created for the design, construction, reconstruction and operation of railways. A large length of Railways in Russia requires solving a number of problems in the conditions of increasing the accuracy of determining the coordinates. High-speed route crosses several regions with its own local coordinate systems. Simplify the design and cadastral works and reduce to minimum linear distortions when performing geodetic measurements, allows the creation of a local coordinate system, unified for the entire route. The technology of creating a unified local coordinate system for linear objects passing through several 6-degree zones in the projection of GaussKruger and objects located at an angle to the axial Meridian is considered on the example of the railway Moscow — Saint-Petersburg — Vyborg. At the basis of a unified local system of the object, it is proposed to use an oblique cylindrical cartographic projection. Implemented a coordinate system in the form of the software, allowing to perform transformations between the local system, the world and state coordinate systems. The paper also considers the practical experience of creating a high-precision geodetic reference network for a high-speed railway traffic route, which can be used for various linear engineering structures. The created frame network can serve as a geodetic base for performing laser scanning, monitoring facilities, creating geoinformation systems and solving other problems that arise during the operation of an engineering facility.

Abstract Definitive transition to GNSS technology of achieving geodetic networks for cadastre implementation in cities and municipalities, enforce establishing a unique way of linking between current measurements and existing geodetic data, with a sufficient accuracy proper to urban cadastre standards. Regarding city of Iasi, is presented a different method of transformation which consist in an interpolation grid for heights system. The Romanian national height system is „Black Sea-1975” normal heights system. Founded in 1945 by Molodenski, this system uses the quasigeoid as reference surface, being in relation with the ellipsoid through the height anomalies sizes in each point. The unitary transformation between the ETRS- 89 ellipsoidal height system and the normal one, at national level is provided through the „TransdatRo” program developed by NACLR (National Agency for Cadastre and Land Registration).

In article the local automatized geodetic network (MAGS) that provides RTK and post-processed relative positioning for geotechnical monitoring. The net based on using of GNSS receiv-ers and software which made in Russia. The results of practical tests are showed.

Due to the great importance of geodetic networks for the formation of a unified coordinate system on the territory of Ukraine, external geodetic signs have been established, which need to be restored and further developed. At the design stage, the calculation of the heights of geodetic signs is performed on topographic maps. The cost of erection of geodetic signs on average is 50 - 60% of the total cost of creating a geodetic network, so there is a need to pay close attention to the choice of places to build signs that provide their optimal height. The article presents a methodical approach to determining the heights of external geodetic signs, based on the mathematical apparatus used for modeling and solving optimization problems. The principle of construction of the optimization model of the problem during the design of external geodetic signs in the conditions when their direct visibility should be provided is considered. The article considers in detail the types and structures of external geodetic signs, identifies the features of their location and construction. The resulting optimization model includes objective function, which is a quadratic form, and line restriction. This model is a model of quadratic programming, that belongs to a class of nonlinear programming models, but have their particular case and the simplest of nonlinear. This is because property quadratic model, which consists in the fact that since the problem of quadratic programming set of feasible solutions is convex, then, if the objective function is concave, any local maximum is global, and if the objective function is convex, then any local minimum is also global. The necessity of solving the problem of optimizing the heights of geodetic signs is substantiated, which is still connected with the financial costs for their construction and reconstruction. It is concluded that the approach to determining the heights of external geodetic signs presented in the article, which uses a mathematical apparatus for solving optimization problems, is an effective and efficient approach, and allows to numerically justify the minimum required and sufficient height of external geodetic signs. Using the present approach to the determination of geodetic heights external signs to optimize the financial costs of their construction, which is essential.

Pretty before long there will be transition to the geodetic system of coordinates of GSK-2011. For the transition period it is necessary to develop a method of recalculating coordinates from one system to another. The existing methods of recalculating coordinates are designed for recalculating coordinate points of state geodetic networks (GGS) and geodetic local networks (GSS). For small areas (administrative districts, populated areas) simplified methods are more acceptable. You need to choose the resampling methods that can be applied in small businesses, performing surveying works. The article presents the the results of calculations of changes of coordinates of the same point in GSK-2011 and SC-95 in six-degree zones of Gauss projection. It was found that in each region values of the shifts changed to small ones. Therefore, it is possible to convert the coordinates of the points by the simplified formulae. For recalculation from the coordinates of GSK-2011 in SK-95 or local coordinate system (WCS) of the administrative district it is necessary to find the origin of coordinates, scale value and rotation of the coordinate axes. The error of the conversion shall not exceed 0,001 m. The coordinates of the initial point of the local coordinate system relative to the central meridian of the local coordinate system shall be added in the list of parameters of the transition from local coordinate system to the state one.

AbstractHellenic Military Geographical Service (HMGS) has established and measured various networks in Greece which constitute the geodetic infrastructure of the country. One of them is the triangulation network consisting of about 26.000 pillars all over Greece. Classical geodetic measurements that held by the Hellenic Military Geographic Service (HMGS) through the years have been used after adjustment for the state reference frame which materializes the current Hellenic Geodetic Reference System of 1987 (HGRS87). The aforementioned Reference System (RS) is a static one and is in use since 1990. Through the years especially in the era of satellite navigation systems many Global Navigation Satellite System (GNSS) networks have been established. The latest such network materialized by HMGS is ongoing and covers until now more than the 2/3 of the country. It is referenced by International GNSS Service (IGS) permanent stations and consists a local densification IGS08 Reference Frame. Firstly, this gives the opportunity to calculate transformation parameters between the two systems and a statistical analysis of the residuals leads to intermediate conclusions. After that and in conjunction with existing past transformations, tectonic deformations and their directions are concluded. Moreover past GPS observations on the same pillars in compare to the newer ones give also a sense of tectonic displacements. Greece is one of the most tectonically active countries in Europe and the adoption of a modern kinematic or semi-kinematic geodetic datum is a necessity as it should incorporate a deformation model like 3d velocities on the reference frame realization. The detection of geodynamic changes is a continuous need and should be taken into consideration at each epoch.

U doktorskoj disertaciji je prikazan postupak optimizacije podzemne mrežeza potrebe izgradnje beogradskog metroa. U postupku optimizacije korišćenje metod prethodne ocene tačnosti. Na osnovu građevinskih standardaizvršen je proračun zahtevane tačnosti proboja tunela, kao osnovnogkriterijuma tačnosti za razvijanje podzemne tunelske mreže. U postupkuoptimizacije analizirani su različiti planovi opažanja, kao i dobijeni rezultatiprethodne analize za svaki plan pojedinačno. Na osnovu zadatog kriterijumamaksimalne poprečene greške proboja tunela usvojen je konačan planopažanja.
The docotoral thesis presents an optimization method of the undergroundnetwork for the construction of the Belgrade metro. In the process ofoptimization, method of preanalysis has been used. Based on theconstruction standards, the calculation of the required breakthroughaccuracy, as the fundamental criteria of accuracy for the development of theunderground tunnel network, has been made. In the process of optimizationdifferent plans of observations have been analyzed, as well as the resultsobtained from the preanalysis for each plan individually. Based on therequired criteria of maximal transverse error of the tunnel breakthrough, thefinal plan of observations has been adopted.

[EN] The goal of this research is to analise and to develop a system that allows the determination of the most general movement dynamics of a tall building, as well as to quantify its evolution over time by means of Gaussian algorithms revision and by applying GNSS techniques and methodologies. In this thesis, the oscillation of the control quadrilateral located on the roof of the ``Torre Espacio'' bulding and determined by a high precision survey network is assessed rigorously with the method of sequential solution with addition of variables or parameters using VRS-RTK techniques. It is the data processing, together with the gaussian adjustment methodology based on a conditional tax own physical reality and analysis of partial and final results allowing us to achieve a high level of confidence that translates into effective management real-time risk. In parallel, the instantaneous and simultaneous precision of each antenna in every moment is determined. That is the error surface and the individual, simultaneous reliability of each GNSS receiver. Prior to assessing the structure dynamics, the sensitivity threshold is computed, under which nothing can be affirmed or denied with respect to the displacement produced in the control structure. It involves testing the accuracy of the instrumentation GNSS and gaussian initial adjustment mathematical model. The project concludes with the development of a warning system that is activated at the time when the movement of the building reaches a preset threshold.
[ES] El objeto de la investigación es analizar y desarrollar un sistema que permita determinar la dinámica más general del movimiento de un edificio de gran altura, así como cuantificar su evolución en el tiempo. Dicho sistema se plantea mediante la revisión de los algoritmos gaussianos y la aplicación de metodologías y técnicas GNSS. En este trabajo se determina rigurosamente, mediante el método general de Ajustes Coordinados con adición de funciones de variables o parámetros, la situación de oscilación del cuadrilátero de control conformado por una red microgeodésica local y observado con técnicas VRS-RTK ubicado en la planta de coronación del edificio Torre Espacio de Madrid. Es precisamente el tratamiento de los datos, la metodología gaussiana de ajuste en función de un condicionado propio impuesto por la realidad física y el análisis de los resultados parciales y finales lo que nos permite alcanzar un alto nivel de fiabilidad que se traduce en una gestión eficaz del riesgo en tiempo real. Paralelamente se determina la precisión instantánea y simultánea de cada antena y en cada momento, esto es la superficie de error y la fiabilidad individual y simultánea de la posición de cada receptor GNSS. Previo a la evaluación de la dinámica de la estructura, se calcula el umbral de precisión o ``sensibilidad'', por debajo del cual nada puede afirmarse o negarse con respecto al desplazamiento producido en la estructura a controlar. Supone contrastar la precisión de la instrumentación GNSS y del modelo matemático inicial de ajuste gaussiano. El proyecto concluye con el desarrollo de un sistema de alerta que se activa en el momento en que el movimiento del edificio alcanza un umbral preestablecido.
[CAT] L'objecte de la investigació és analitzar i desenvolupar un sistema que permeta determinar la dinàmica més general del moviment d'un edifici de gran alçada, així com quantificar la seua evoluvió en el temps. Aquest sistema es plantaja mitjançant la revisió dels algorismes Gaussians i l'aplicació de metodologies y tècniques GNSS. En aquest treball es determina rigorosament, mitjançant el mètode general d'Ajusts Coordinats amb adició de de funcions de variables o paràmetres, la situació d'oscilació del quadrilàter de control conformat per una xarxa microgeodèsica local i observant amb tècniques VRS-RTK localitzat a la planta de coronació de l'edifici TorreEspacio de Madrid. És precisament el tractament de les dades, la metodologia Gaussiana d'ajust en funció d'un condicionat propi imposat per la realitat física y l'anàlisi dels resultats parcials i finals el que ens permet arribar a un alt nivell de fiabilitat, que es tradieix en una gestió eficaç del risc en temps real. Paral·lelament es determina la precisió instantània i simultània de cada antena i en cada moment, es a dir la superfície d'error i la fiabilitat individual i simultània de la posició de cada receptor GNSS. Previament a l'evaluació de la dinàmica de l'estructura, es calcula l'umbral de precisió o ``sensibilitat'', per davall de la qual no es por afirmar o negar res respecte al desplaçament produït en l'estructura a controlar. Això suposa contrastar la precisió de la instrumentació GNSS i del model matemàtic inicial d'ajust Gaussià. El projecte conclou amb el desenvolupament d'un sistema d'alerta que s'activa en el moment en que el moviment de l'edifici arriba a un umbral preestablert.
Quesada Olmo, MN. (2015). Desarrollo y análisis de un sistema para la determinación de la dinámica del movimiento más general de la azotea de un edificio de gran altura y su evolución en el tiempo [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/58993
TESIS

Establishing a claim to the continental shelf is very much dependent on being able to establish base lines, locations, distances and water depth with a high degree of accuracy. Although this has always been the case, it has become much more significant with the increasing accuracy of measurement instrumentation, the introduction of global (satellite) positioning systems, and the need for international collaboration and agreement. This chapter outlines the measurements or calculations relating to position on the surface of the Earth, the geodetic principles underlying the concepts of coordinates and their reference systems, and the level of accuracy with which positions can be determined. Until the advent of satellite positioning and navigation systems, and in particular the Global Positioning System (GPS), geodetic coordinate systems were of little interest to many of the users of coordinate position information. Indeed, many of today's problems stem from historical misunderstanding of the true complexity of systems of coordinates (Ashkenazi, 1986). The first section of this chapter describes a number of common types of coordinate representation, their implementation in the definition of coordinate systems, and the interpretation of these systems with reference data. Examples of typical local, regional, and geocentric data are outlined as illustration of the general principles. In order to combine coordinates based on differing systems, be it the combination of different national systems or of a national and a geocentric system, it is also necessary to understand the methods of transforming coordinates from one system to another. Details of these methods are presented. Coordinate values within the described systems will usually have been obtained through geodetic observation of national (or international) control networks, with subsequent measurement of detail referenced to those network stations. The chapter therefore gives a brief description of geodetic networks before discussing in some detail the theory of errors and related accuracy analysis which is required in order that realistic accuracy estimates can be ascribed to positional information. The final section presents the definitions and calculation algorithms relating to geodetic distance determination on the Earth's surface, with emphasis on the geodesic— the shortest line between points on an ellipsoidal reference surface, and therefore the line that all distances in article 76 are referred to.

Ubiquitous computing and The Internet-of-Things (IoT) grow rapidly in today's life and evolving to Self-organizing systems (SoS). A unified and scalable information processing and communication methodology is required. In this work, mobile agents are used to merge the IoT with Mobile and Cloud environments seamless. A portable and scalable Agent Processing Platform (APP) provides an enabling technology that is central for the deployment of Multi-Agent Systems (MAS) in strong heterogeneous networks including the Internet. A large-scale use-case deploying Multi-agent systems in a distributed heterogeneous seismic sensor and geodetic network is used to demonstrate the suitability of the MAS and platform approach. The MAS is used for earthquake monitoring based on a new incremental distributed learning algorithm applied to seismic station data, which can be extended by ubiquitous sensing devices like smart phones. Different (mobile) agents perform sensor sensing, aggregation, local learning and prediction, global voting and decision making, and the application.

During reconstruction and restoration of city geodetic networks, there is quite a common problem that is related to the nonhomogeneity of existing geodetic networks. In any city, local authorities operate with their coordinate systems. Such conditions lead to inconsistency between data of different services. There is only one way how to overcome the problem that lies in the creation and deployment of the new common coordinate system for the whole city. But such an approach has a lack connected with the necessity of transformation parameters acquisition for the latest and old coordinate systems. Insofar as old coordinate systems had been created with different accuracy, using various equipment, and measuring technologies, it is not possible to consider them as homogeneous. It means that we cannot use a classical conformal Helmert transformation to link different coordinate systems. In the presented paper were studied the different approaches for transformation parameters acquisition. A case study of the Almaty city coordinate system was researched and compared the following methods: Helmert transformation, bilinear transformation, the second and third-order regression transformation, and the fourth-order conformal polynomial transformation. It was found out that neither of the considered methods maintains the necessary transformation accuracy (>5 cm). That is why the creation of the transformation field using the finite element method (FEM) was suggested. The whole city was divided into triangles using Delaunay triangulation. For each triangle, the transformation parameters were found using affine transformation with the necessary accuracy.