To see the other types of publications on this topic, follow the link: Local Geodetic Network.
Journal articles on the topic 'Local Geodetic Network'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Local Geodetic Network.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Celms, Armands, Velta Parsova, Ilona Reke, and Janis Akmentins. "Tendencies of development of local geodetic network in Riga city." Baltic Surveying 9 (December 5, 2018): 8–15. http://dx.doi.org/10.22616/j.balticsurveying.2018.013.
Full textAbstract:
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.
2
Celms, Armands, Ilona Reke, Miks Brinkmanis-Brimanis, and Vivita Pukite. "Evaluation of the Local Geodetic Network in Jurmala City." Baltic Surveying 10 (June 1, 2019): 8–15. http://dx.doi.org/10.22616/j.balticsurveying.2019.001.
Full textAbstract:
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.
3
Ziggah, Y. Y., I. Yakubu, and B. Kumi-Boateng. "Analysis of Methods for Ellipsoidal Height Estimation – The Case of a Local Geodetic Reference Network." Ghana Mining Journal 16, no. 2 (December 20, 2016): 1–9. http://dx.doi.org/10.4314/gm.v16i2.1.
Full textAbstract:
Ghana’s local geodetic reference network is based on the War Office 1926 ellipsoid with data in latitude, longitude and orthometric height without the existence of ellipsoidal height. This situation makes it difficult to apply the standard forward transformation equation for direct conversion of curvilinear geodetic coordinates to its associated cartesian coordinates (X, Y, Z) in the Ghana local geodetic reference network. In order to overcome such a challenge, researchers resort to various techniques to obtain the ellipsoidal height for a local geodetic network. Therefore, this paper evaluates, compares, and discusses different methods for estimating ellipsoidal height for a local geodetic network. The investigated methods are the Abridged Molodensky transformation model, Earth Gravitational Model, and the Orthometric Height approach. To evaluate these methods, their estimated local ellipsoidal height values were implemented in the seven-parameter similarity transformation model of Bursa-Wolf. The performance of each of the methods was assessed based on statistical indicators of Mean Square Error (MSE), Mean Absolute Error (MAE), Horizontal Position Error (HE) and Standard Deviation (SD). The statistical findings revealed that, the Abridged Molodensky model produced more reliable transformation results compared with the other methods. It can be concluded that for Ghana’s local geodetic network, the most practicable method for estimating ellipsoidal height is the Abridged Molodensky transformation model. Keywords: Abridged Molodensky Model, Earth Gravitational Model, Orthometric Height, Geodetic Network
4
Rosalen, David Luciano. "Influence of distance, geometry and number of control stations on quality of local geodetic networks for the purpose of georeferencing of rural properties." Engenharia Agrícola 34, no. 2 (April 2014): 311–21. http://dx.doi.org/10.1590/s0100-69162014000200012.
Full textAbstract:
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.
5
Matveev, A. Yu, I. P. Gavrilova, A. V. Kovyazin, and E. V. Brovkov. "CONSTRUCTION OF FRAME GEODETIC NETWORK FOR ENGINEERING SURVEY OF RAIL TRANSPORT FACILITIES." Engineering survey 12, no. 5-6 (August 16, 2018): 58–71. http://dx.doi.org/10.25296/1997-8650-2018-12-5-6-58-71.
Full textAbstract:
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.
6
Margaryan, Venera. "Analysis of Quasi-Geoid Model Created for Territory of the Republic of Armenia." Advanced Materials Research 1020 (October 2014): 484–87. http://dx.doi.org/10.4028/www.scientific.net/amr.1020.484.
Full textAbstract:
Abstract: National Geodesic Network of WGS-84 system was founded in the territory of the Republic of Armenia from 2002 to 2007, which includes zero, first, and second class 1115 stations and there were other 229 State Geodesic Triangular Network stations. The observation at these stations has been done by GPS system. Each of the above mentioned stations covers on the average 27 square kilometers of the territory of Armenia. The data obtained during GPS observations have become the foundation for creating local quasi-geoid models and obtaining differences of heights (geoid wave value) of normal and WGS-84 ellipsoid surfaces. On the basis of gravimetric data a quasi-geoid model has been computed and developed. To creat the model coordinates of four geodetic satations encompassing the area of the Republic of Armenia have been used. To get the digital model of the selected area was diveded into five-minute sections by latitude and longitude and then coordinates of geodetic points have been taken. The above mentioned points were recalculated from the local system to WGS-84 system. The creation of the local elippsoid quasi-model is conditioned by the difference of 3D coordinates difference of three-dimensional of each point’s position. The values of the geoid wave vary within the range of 17.4547 meters, the average difference being almost in the centre of the area and is 21.2522 meters. To obtain the digital model of the quasi-geoid at the given local ellipsoid at each 100m a square matrix (of the network) was made by coordinates of recomputed points.
7
Alvarez, Gabriel O. "Identifying and Allocating Geodetic Systems to historical oil gas wells by using high-resolution satellite imagery." Proceedings of the ICA 1 (May 16, 2018): 1–7. http://dx.doi.org/10.5194/ica-proc-1-4-2018.
Full textAbstract:
Hydrocarbon exploration in Argentina started long before the IGM created a single, high-precision geodetic reference network for the whole country. Several geodetic surveys were conducted in every producing basin, which have ever since then supported well placement. Currently, every basin has a huge amount of information referenced to the so-called “local” geodetic systems, such as Chos Malal – Quiñi Huao in the Neuquén Basin, and Pampa del Castillo in the San Jorge Basin, which differ to a greater or lesser extent from the national Campo Inchauspe datum established by the IGM in 1969 as the official geodetic network. However, technology development over the last few years and the expansion of satellite positioning systems such as GPS resulted in a new world geodetic order. Argentina rapidly joined this new geodetic order through the implementation of a new national geodetic system by the IGM: POSGAR network, which replaced the old national Campo Inchauspe system. However, this only helped to worsen the data georeferencing issue for oil companies, as a third reference system was added to each basin. Now every basin has a local system, the national system until 1997 (Campo Inchauspe), and finally the newly created POSGAR network national satellite system, which is geocentric unlike the former two planimetric datums. The purpose of this paper is to identify and allocate geodetic systems of coordinates to historical wells, whose geodetic system is missing or has been erroneously allocated, by using currently available technological resources such as geographic information systems and high-resolution satellite imagery.
8
Ganesamoorthy, Kathiresan, and Duraisamy Jayanthi. "Further results on the outer connected geodetic number of a graph." Publications de l'Institut Math?matique (Belgrade) 108, no. 122 (2020): 79–89. http://dx.doi.org/10.2298/pim2022079g.
Full textAbstract:
For a connected graph G of order at least two, an outer connected geodetic set S in a connected graph G is called a minimal outer connected geodetic set if no proper subset of S is an outer connected geodetic set of G. The upper outer connected geodetic number g+ oc(G) of G is the maximum cardinality of a minimal outer connected geodetic set of G. We determine bounds for it and find the upper outer connected geodetic number of some standard graphs. Some realization results on the upper outer connected geodetic number of a graph are studied. The proposed method can be extended to the identification of beacon vertices towards the network fault-tolerant in wireless local access network communication. Also, another parameter forcing outer connected geodetic number fog(G) of a graph G is introduced and several interesting results and realization theorem are proved.
9
Radovanovic, R. S., N. EI-Sheimy, T. Richert, and W. F. Teskey. "Local datum definition and geodetic network positioning using global navigation satellite systems." Journal of Geodesy 78, no. 4-5 (October 20, 2004): 283–94. http://dx.doi.org/10.1007/s00190-004-0400-7.
Full text
10
Foumelis, M. "Velocity field and crustal deformation of broader Athens plain (Greece) from a dense geodetic network." Journal of Applied Geodesy 13, no. 4 (October 25, 2019): 305–16. http://dx.doi.org/10.1515/jag-2019-0012.
Full textAbstract:
Abstract The broader area of Athens, a region exhibiting relatively low crustal deformation, was stroke in 1999 by a catastrophic earthquake posing serious questions regarding strain accumulation in slow deforming regions located within active geodynamic regimes. In the present study, the establishment of a dense geodetic network, primarily designed to monitor local tectonic movements is reported. A comprehensive GNSS velocity field, over the period 2005–2008, as well as calculated geodetic strain rates is presented. It is shown that a single strain tensor is insufficient to express the heterogeneity of the local geodetic field. Local variability of strain is successfully depicted, indicating the western part of Athens as the area of higher strain accumulation. Maximum dilatation rates occur along a NNE-SSW direction between Parnitha Mt. and Thriasio basin. The observed dilatation can be associated to WNW-ESE trending active fault zones, which appear to abruptly terminate towards East along a major NNE-SSW Miocene tectonic boundary. These findings are consistent to the stress field responsible for the Athens 1999 earthquake, also in agreement with geological and tectonic observations. Finally, the implications of the observed motion field on the understanding of the kinematics and dynamics of the region as well as the role of inherited inactive tectonic structures are discussed.
11
Ziggah, Yao Yevenyo, John Ayer, Prosper Basommi Laari, and Eric Frimpong. "COORDINATE TRANSFORMATION USING FEATHERSTONE AND VANÍČEK PROPOSED APPROACH - A CASE STUDY OF GHANA GEODETIC REFERENCE NETWORK." Geoplanning: Journal of Geomatics and Planning 4, no. 1 (September 29, 2016): 19. http://dx.doi.org/10.14710/geoplanning.4.1.19-26.
Full textAbstract:
Most developing countries like Ghana are yet to adopt the geocentric datum for its surveying and mapping purposes. It is well known and documented that non-geocentric datums based on its establishment have more distortions in height compared with satellite datums. Most authors have argued that combining such height with horizontal positions (latitude and longitude) in the transformation process could introduce unwanted distortions to the network. This is because the local geodetic height in most cases is assumed to be determined to a lower accuracy compared with the horizontal positions. In the light of this, a transformation model was proposed by Featherstone and Vaníček (1999) which avoids the use of height in both global and local datums in coordinate transformation. It was confirmed that adopting such a method reduces the effect of distortions caused by geodetic height on the transformation parameters estimated. Therefore, this paper applied Featherstone and Vaníček (FV) model for the first time to a set of common points coordinates in Ghana geodetic reference network. The FV model was used to transform coordinates from global datum (WGS84) to local datum (Accra datum). The results obtained based on the Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) in both Eastings and Northings were satisfactory. Thus, a RMSE value of 0.66 m and 0.96 m were obtained for the Eastings and Northings while 0.76 m and 0.73 m were the MAE values achieved. Also, the FV model attained a transformation accuracy of 0.49 m. Hence, this study will serve as a preliminary investigation in avoiding the use of height in coordinate transformation within Ghana’s geodetic reference network.
12
Shevchuk, Stanislav, Vadim Ponomarev, Elena Cheremisina, and Sergey Ivanov. "EXPERIENCE OF USING PRACTICE OF LOCAL AUTOMATIZED GEODETIC NETWORKS BASED ON DOMESTIC GNSS RECEIVERS." Interexpo GEO-Siberia 1, no. 1 (2019): 28–35. http://dx.doi.org/10.33764/2618-981x-2019-1-1-28-35.
Full textAbstract:
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.
13
Voronkov, O., O. Baistryk, and A. Danylyuk. "MATHEMATICAL MODELING OF OPTIMAL HEIGHTS OF EXTERNAL GEODESIC SIGNS." Municipal economy of cities 1, no. 161 (March 26, 2021): 109–15. http://dx.doi.org/10.33042/2522-180-2021-1-161-109-115.
Full textAbstract:
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.
14
SILVA, E. V., and A. SEIXAS. "Analysis of the Stability of the Local Altimetric Geodetic Network Densified on the Campus Recife UFPE." Anuário do Instituto de Geociências - UFRJ 42, no. 2 (August 9, 2019): 350–65. http://dx.doi.org/10.11137/2019_2_350_365.
Full text
15
Jiang, Z., F. Wang, J. Bai, and Z. Li. "CONSTRUCTION THEORY AND NOISE ANALYSIS METHOD OF GLOBAL CGCS2000 COORDINATE FRAME." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-3 (April 30, 2018): 679–84. http://dx.doi.org/10.5194/isprs-archives-xlii-3-679-2018.
Full textAbstract:
The definition, renewal and maintenance of geodetic datum has been international hot issue. In recent years, many countries have been studying and implementing modernization and renewal of local geodetic reference coordinate frame. Based on the precise result of continuous observation for recent 15 years from state CORS (continuously operating reference system) network and the mainland GNSS (Global Navigation Satellite System) network between 1999 and 2007, this paper studies the construction of mathematical model of the Global CGCS2000 frame, mainly analyzes the theory and algorithm of two-step method for Global CGCS2000 Coordinate Frame formulation. Finally, the noise characteristic of the coordinate time series are estimated quantitatively with the criterion of maximum likelihood estimation.
16
Papadopoulos, Nestoras, Melissinos Paraskevas, Ioannis Katsafados, Georgios Nikolaidis, and Euagelos Anagnostou. "Deformation detection through the realization of reference frames." Journal of Applied Geodesy 14, no. 2 (April 26, 2020): 133–48. http://dx.doi.org/10.1515/jag-2019-0056.
Full textAbstract:
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.
17
Pacina, Jan. "Geodetic surveying as part of archaeological research in Sudan." Geoinformatics FCE CTU 14, no. 1 (June 27, 2015): 47–64. http://dx.doi.org/10.14311/gi.14.1.4.
Full textAbstract:
<p>Surveying is an important part of any archaeological research. In this paper we focus on the archaeological research in north Sudan (6<sup>th</sup> Nile cataract) and the surveying methods applicable under the local conditions. Surveying in the Third World countries is affected by the political situation (limited import of surveying tools), local conditions (lack of fixed points, GNSS correction signal), inaccessible basemaps and fixed point network. This article describes the methods and results obtained during the three archaeological seasons (2011-2014). The classical surveying methods were combined with KAP (Kite Aerial Photography) to obtain the desired results in form of archaeological maps, detailed orthophoto images and other analyses results.</p>
18
Forsberg, Rene. "Experience with the ULISS-30 inertial survey system for local geodetic and cadastral network control." Bulletin Géodésique 65, no. 3 (September 1991): 179–88. http://dx.doi.org/10.1007/bf00806347.
Full text
19
Parent, C., and M. C. Pinch. "NAD83 SECONDARY INTEGRATION." CISM journal 42, no. 4 (January 1988): 331–40. http://dx.doi.org/10.1139/geomat-1988-0028.
Full textAbstract:
The Canadian geodetic network that was adjusted with networks of other North American countries, in the July 1986 Continental Adjustment, included only the 8000-station national primary framework. There still remains many thousands of stations contained in regional and local secondary networks to integrate into the North American Datum of 1983 (NAD83). Secondary Integration is a cooperative project organized by member agencies of the Canadian Control Survey Committee (CCSC) which first met in 1982. Since then, members have automated and evaluated secondary network data for approximately 100 000 stations established by conventional, inertial and satellite surveying methods. The task of compiling and testing Helmert blocks for input to the simultaneous adjustment of primary and secondary networks is now underway. This paper describes the plans and progress, and some of the problems that challenge us in the NAD83 Secondary Integration Project.
20
De Guidi, Giorgio, Alessia Vecchio, Fabio Brighenti, Riccardo Caputo, Francesco Carnemolla, Adriano Di Pietro, Marco Lupo, et al. "Brief communication: Co-seismic displacement on 26 and 30 October 2016 (<i>M</i><sub>w</sub> = 5.9 and 6.5) – earthquakes in central Italy from the analysis of a local GNSS network." Natural Hazards and Earth System Sciences 17, no. 11 (November 9, 2017): 1885–92. http://dx.doi.org/10.5194/nhess-17-1885-2017.
Full textAbstract:
Abstract. On 24 August 2016 a strong earthquake (Mw = 6.0) affected central Italy and an intense seismic sequence started. Field observations, DInSAR (Differential INterferometry Synthetic-Aperture Radar) analyses and preliminary focal mechanisms, as well as the distribution of aftershocks, suggested the reactivation of the northern sector of the Laga fault, the southern part of which was already rebooted during the 2009 L'Aquila sequence, and of the southern segment of the Mt Vettore fault system (MVFS). Based on this preliminary information and following the stress-triggering concept (Stein, 1999; Steacy et al., 2005), we tentatively identified a potential fault zone that is very vulnerable to future seismic events just north of the earlier epicentral area. Accordingly, we planned a local geodetic network consisting of five new GNSS (Global Navigation Satellite System) stations located a few kilometres away from both sides of the MVFS. This network was devoted to working out, at least partially but in some detail, the possible northward propagation of the crustal network ruptures. The building of the stations and a first set of measurements were carried out during a first campaign (30 September and 2 October 2016). On 26 October 2016, immediately north of the epicentral area of the 24 August event, another earthquake (Mw = 5.9) occurred, followed 4 days later (30 October) by the main shock (Mw = 6.5) of the whole 2016 summer–autumn seismic sequence. Our local geodetic network was fully affected by the new events and therefore we performed a second campaign soon after (11–13 November 2016). In this brief note, we provide the results of our geodetic measurements that registered the co-seismic and immediately post-seismic deformation of the two major October shocks, documenting in some detail the surface deformation close to the fault trace. We also compare our results with the available surface deformation field of the broader area, obtained on the basis of the DInSAR technique, and show an overall good fit.
21
Kaviris, George, Panagiotis Elias, Vasilis Kapetanidis, Anna Serpetsidaki, Andreas Karakonstantis, Vladimír Plicka, Louis De Barros, et al. "The Western Gulf of Corinth (Greece) 2020–2021 Seismic Crisis and Cascading Events: First Results from the Corinth Rift Laboratory Network." Seismic Record 1, no. 2 (July 1, 2021): 85–95. http://dx.doi.org/10.1785/0320210021.
Full textAbstract:
Abstract We investigate a seismic crisis that occurred in the western Gulf of Corinth (Greece) between December 2020 and February 2021. This area is the main focus of the Corinth Rift Laboratory (CRL) network, and has been closely monitored with local seismological and geodetic networks for 20 yr. The 2020–2021 seismic crisis evolved in three stages: It started with an Mw 4.6 event near the northern shore of the Gulf, opposite of Aigion, then migrated eastward toward Trizonia Island after an Mw 5.0 event, and eventually culminated with an Mw 5.3 event, ∼3 km northeast of the Psathopyrgos fault. Aftershocks gradually migrated westward, triggering another cluster near the junction with the Rion–Patras fault. Moment tensor inversion revealed mainly normal faulting; however, some strike-slip mechanisms also exist, composing a complex tectonic regime in this region dominated by east–west normal faults. We employ seismic and geodetic observations to constrain the geometry and kinematics of the structures that hosted the major events. We discuss possible triggering mechanisms of the second and third stages of the sequence, including fluids migration and aseismic creep, and propose potential implications of the Mw 5.3 mainshock for the seismic hazard of the region.
22
Gašincová, Silvia, Dušan Kneţo, Ladislav Mixtaj, and Peter Harman. "Impacts of Measuring and Numerical Errors in Lsm Adjustment of Local Geodetic Network / Vplyvy Meračských A Výpočtových Chýb V Mnš Vyrovnaní Lokálnej Geodetickej Siete." GeoScience Engineering 57, no. 1 (March 1, 2011): 1–8. http://dx.doi.org/10.2478/gse-2014-0018.
Full textAbstract:
Abstract The Local Geodetic Network (LGN) adjustment is affected by various errors, whether arisen from measuring or calculating works. The measuring errors occurred in the consistent LGS measuring can be detected by control calculations in dL using redundant measurements. The numerical errors may be detected, or the accuracy of the formulas used can be verified by control calculations in a configuration matrix A and control relations, which should show zero values.
23
Younis, Ghadi. "The Effect of Using Multiple Coordinate Systems and Datum Transformations on the Calculated Coordinates in Palestine." Bulletin of Geography. Physical Geography Series 19, no. 1 (December 4, 2020): 31–41. http://dx.doi.org/10.2478/bgeo-2020-0008.
Full textAbstract:
AbstractThe recent developments in spatial data collection, management and software require the availability of proper geodetic infrastructures for integrating different types and sources of coordinates without causing effective changes in positions. Nowadays, positions are mostly collected by GNSS data collectors based on WGS84/ITRF reference systems. The data are then subjected to transformations and projections to a locally used system. Another possibility is direct data collection based on the local coordinate system by classical surveys using land surveying, photogrammetry, laser scanning, etc. The spatial data management is commonly operated using Geographic Information Systems (GIS) software for mapping, analysis, planning, and other services. The conversions between different coordinate systems should be well defined to guarantee the consistency of the coordinates on all systems and tools. In Palestine, the classical and local surveys are all based on the local coordinate system Pal1923Grid for engineering, cadastral and planning applications. The different GNSS RTK-service providers use different definitions and transformation methods between WGS84 or the International Terrestrial Reference Frames (ITRF) and the local Palestine1923Grid, whereas the Land authority has adopted a group of parameters to be implemented on the Global Navigation Satellite Systems (GNSS) data collectors, which do not fit with Palestine1923Grid properties. Additionally, different transformation methods are used in GIS applications for converting the coordinates between the different systems using WGS84 as an intermediate system. Here, the coordinates of a group of the geodetic network in the West Bank of Palestine are used to assess the accuracy of the different transformations and systems by comparing the transformed coordinates using the GNSS system and the originally registered coordinates. Furthermore, a grid of points covering the coordinate system extents is used to describe the differences between the transformations and systems. It was found that the parameters provided by GNSS service providers have results that are consistent with each other and the geodetic network in the West Bank of Palestine compared to GIS-software parameters. By contrast, all systems have extremely deteriorated coordinates in the Gaza strip and the further parts of the Pal1923Grid extents.
24
Akcin, Hakan, and Cahit Tagi Celik. "Performance of artificial neural networks on kriging method in modeling local geoid." Boletim de Ciências Geodésicas 19, no. 1 (March 2013): 84–97. http://dx.doi.org/10.1590/s1982-21702013000100006.
Full textAbstract:
Transformation of ellipsoidal heights determined by satellite techniques into local leveling heights requires geoid heights at points of interest. However, the geoid heights at each point are not available. In order to determine them, the local geoid in the transformation area must be modeled or computed by an appropriate method, one way of doing it, is to use control points both of whose ellipsoidal and local leveling heights are available. In this study, performance of geoid by ANN compared to Kriging method in modeling local geoid was presented. Moreover, the transformation ability of the methods was investigated through a geodetic test network in Bursa Metropolitan Area of Turkey. The results suggest that the model by ANN exhibit better results than the one by Kriging Method.
25
Tereshchenko, Vyacheslav E., Andrey V. Radchenko, and Vyacheslav A. Melkiy. "GLOBAL REFERENCE SYSTEM AND ITS LOCAL REALIZATION – RUSSIAN STATE COORDINATE SYSTEM GSK-2011." Vestnik SSUGT (Siberian State University of Geosystems and Technologies) 25, no. 3 (2020): 89–106. http://dx.doi.org/10.33764/2411-1759-2020-25-3-89-106.
Full textAbstract:
The article highlights the issue of interpreting reference stations networks as a local realization of the global reference system. The substantiation of the proposed approach is given and its advantages are shown. The rationale for the proposed approach is given and its advantages are shown. In particular, the top block in the structure of the formation of the Russian state coordinate system (GSK‑2011) is the fundamental astronomical and geodetic network. It is a regional realization of a global reference system. The creation of GSK‑2011 was carried out with a focus on the global International Terrestrial Reference System (ITRS) however geodynamic processes affecting the displacement of reference points relative to the center of the Earth's masses play a different role in the time evolution of systems. Such processes in GSK‑2011 are not subject to accounting, since the system was created to conduct various types of applied geodetic and cartographic activities in it. In this case, taking into account the constant change in the coordinates of reference points is almost never implied. In this regard, the asynchronous movement of the Russian state coordinate system (GSK‑2011) with the global reference system (ITRS) began to lead to inconsistencies in the results of high-precision positioning performed at different times, by different methods. Based on this, the necessity to find a way of matching GSK‑2011 to ITRS is urgent. The article presents the rates of change of the match parameters of the above-mentioned systems. These parameters make it possible to match the results of high-precision positioning performed in different reference systems using different methods of positioning for different epochs of the GNSS observations. The experiment carried out in the second part of the article confirms this.
26
Vinogradov, A. V. "Determining the parameters of a local coordinate system with a non-standard longitude of the central meridian. Analysis of existing methods." Geodesy and Cartography 960, no. 6 (July 20, 2020): 2–12. http://dx.doi.org/10.22389/0016-7126-2020-960-6-2-12.
Full textAbstract:
Processing the results of topographic and geodetic works is performed in local coordinate systems. The parameters of the local coordinate systems were established on the basis of SK-42 or SK-63 systems. At present, it is necessary to set new communication parameters with coordinate systems SK-95 and GSK-2011. In many MCSs, the central meridians do not coincide with the origin, and the coordinates of the starting points were obtained from the catalogs of the preliminary calculation geodetic network. To establish the new communication parameters, it is necessary to determine the longitude of the central meridian MCS in SK-95 and GSK-2011 systems. To find the errors in calculating the longitude of the central meridian, MCS the models were constructed with different positions of the central meridian relative to the origin. The longitude was calculated using well-known and new formulas and methods. Errors in calculating the longitude of the MSC are systematic. An increase in the calculation volume does not exclude the influence of systematic errors, reaching 4ʺ. For some lines, they make 8ʺ.
27
Latynina, L. "GEODYNAMICS." GEODYNAMICS 1(6)2007, no. 1(6) (September 20, 2007): 26–32. http://dx.doi.org/10.23939/jgd2007.01.026.
Full textAbstract:
The character of a geodetic method of study of recent movements of the rocks and method of local measurements are compared. The network of underground deformation stations in Carpathians is considered. The results of station observations and the results of the long-term geodetic measurements which have been carried out in Austria-Hungary are compared. The structure of fields of deformations in western part of the East Carpathians on these data and data of two stations «Muzhievo» and «Beregovo» coincide. The main axes of a field of the deformations have latitude and meridian directions. There is an intensive compression in the latitude azimuth. In east part of the east Carpathians on border with Vigorlat-Guta volcanic ridge the station «Korolevo» registers intensive expansion of the surface in latitude direction. The data of geological and geophysical researches confirm objectivity of the received results.
28
Siejka, Zbigniew. "Verification of the Usefulness of the Trimble Rtx Extended Satellite Technology with the Xfill Function in the Local Network Implementing Rtk Measurements." Artificial Satellites 49, no. 4 (December 1, 2014): 191–209. http://dx.doi.org/10.2478/arsa-2014-0015.
Full textAbstract:
ABSTRACT The paper presents the method of satellite measurements, which gives users the ability of GNSS continuous precise positioning in real time, even in the case of short interruptions in receiving the correction of the local ground system of measurements support. The proposed method is a combination of two satellite positioning technologies RTN GNSS and RTX Extended. In technology RTX Extended the xFill function was used for precise positioning in real time and in the local reference system. This function provides the ability to perform measurement without the need for constant communication with the ground support satellite system. Test measurements were performed on a test basis located in Krakow, and RTN GNSS positioning was done based on the national network of reference stations of the ASGEUPOS. The solution allows for short (up to 5 minutes) interruptions in radio or internet communication. When the primary stream of RTN correction is not available, then the global corrections Trimble xFill broadcasted by satellite are used. The new technology uses in the real-time data from the global network of tracking stations and contributes significantly to improving the quality and efficiency of surveying works. At present according to the authors, technology Trimble CenterPoint RTX can guarantee repeatability of measurements not worse than 3.8 cm (Trimble Survey Division, 2012). In the paper the comparative analysis of measurement results between the two technologies was performed: RTN carried out in the classic way, which was based on the corrections of the terrestrial local network of the Polish system of active geodetic network (ASG-EUPOS) and RTK xFill technology. The results were related to the data of test network, established as error free. The research gave satisfactory results and confirmed the great potential of the use of the new technology in the geodetic work realization. By combining these two technologies of GNSS surveying the user can greatly improve the overall performance of real-time positioning.
29
Mazurov, B. T. "Geodynamic systems (qualitative research rotational movements)." Geodesy and Cartography 919, no. 1 (February 20, 2017): 35–39. http://dx.doi.org/10.22389/0016-7126-2017-919-1-35-39.
Full textAbstract:
Geodetic data and their subsequent statistical analysis enable mathematical modeling and identifying the stress-deformed state of geodynamic systems in concern to the aspect of natural and man-made disasters prediction. Geodetic monitoring geodynamic processes is necessary for solving a number of scientific and practical tasks of geodesy i.e. expanding and maintaining the national geodetic network, studying changes in gravity field in time, using GNSS technology. Most important extension of research is mathematical modelling of geodynamic systems in a predictive order. To study the complex (nonlinear) geodynamic processes the appropriate mathematical framework should be selected. Here are theoretical foundations for studying rotation movements of the earth’s surface. A mathematical model of rotary circular structures of the Earth was mentioned. There are mathematical models explaining the nature of sudden global, regional and some local geodynamic processes. They are based on differences in temporal and spatial scales, of geodynamic systems. Theoretical bases of description rotational motions on a plane by a system of differential equations were considered. Some examples of integral curves were given. They can be qualitative characteristics of geodynamic systems. In many cases, a similar trajectory corresponds to the rotational horizontal movements of the earth’s surface.
30
Bolkas, D., G. Fotopoulos, and M. G. Sideris. "Referencing regional geoid-based vertical datums to national tide gauge networks." Journal of Geodetic Science 2, no. 4 (December 1, 2012): 363–69. http://dx.doi.org/10.2478/v10156-011-0050-7.
Full textAbstract:
AbstractThe objective of this study is to investigate the best means for referencing a regional geoid-based vertical datum to a network of tide gauges. In this study, a network of 27 tide gauge stations scattered along the coasts of Canada are used in order to assess the replacement of the conventionally derived Canadian Geodetic Vertical Datum of 1928 with a geoid-based datum. This is in-line with the future implementation plan of Canada’s geoid-based vertical height system. A mixed least-squares adjustment was performed for various scenarios, including satellite-only global geoid models, combined global geoid models and regional geoid models. In addition, various sea surface topography and vertical ground motion models were tested for estimating orthometric heights. The resulting approximation of a local equipotential surface is compared to previously published values and considerations for referencing a geoid-based vertical datum to tide gauge networks are emphasized.
31
Bonforte, Alessandro, Douglas Antonio Hernandez, Eduardo Gutiérrez, Louis Handal, Cecilia Polío, Salvatore Rapisarda, and Piergiorgio Scarlato. "The unrest of the San Miguel volcano (El Salvador, Central America): installation of the monitoring network and observed volcano-tectonic ground deformation." Natural Hazards and Earth System Sciences 16, no. 8 (August 3, 2016): 1755–69. http://dx.doi.org/10.5194/nhess-16-1755-2016.
Full textAbstract:
Abstract. On 29 December 2013, the Chaparrastique volcano in El Salvador, close to the town of San Miguel, erupted suddenly with explosive force, forming a column more than 9 km high and projecting ballistic projectiles as far as 3 km away. Pyroclastic density currents flowed to the north-northwest side of the volcano, while tephras were dispersed northwest and north-northeast. This sudden eruption prompted the local Ministry of Environment to request cooperation with Italian scientists in order to improve the monitoring of the volcano during this unrest. A joint force, made up of an Italian team from the Istituto Nazionale di Geofisica e Vulcanologia and a local team from the Ministerio de Medio Ambiente y Recursos Naturales, was organized to enhance the volcanological, geophysical and geochemical monitoring system to study the evolution of the phenomenon during the crisis. The joint team quickly installed a multiparametric mobile network comprising seismic, geodetic and geochemical sensors (designed to cover all the volcano flanks from the lowest to the highest possible altitudes) and a thermal camera. To simplify the logistics for a rapid installation and for security reasons, some sensors were colocated into multiparametric stations. Here, we describe the prompt design and installation of the geodetic monitoring network, the processing and results. The installation of a new ground deformation network can be considered an important result by itself, while the detection of some crucial deforming areas is very significant information, useful for dealing with future threats and for further studies on this poorly monitored volcano.
32
Bonforte, A., D. Hernandez, E. Gutiérrez, L. Handal, C. Polío, S. Rapisarda, and P. Scarlato. "The unrest of S. Miguel volcano (El Salvador, CA): installation of the monitoring network and observed volcano-tectonic ground deformation." Natural Hazards and Earth System Sciences Discussions 3, no. 10 (October 9, 2015): 6117–48. http://dx.doi.org/10.5194/nhessd-3-6117-2015.
Full textAbstract:
Abstract. On 29 December 2013, the Chaparrastique volcano in El Salvador, close to the town of S. Miguel, erupted suddenly with explosive force, forming a more than 9 km high column and projecting ballistic projectiles as far as 3 km away. Pyroclastic Density Currents flowed to the north-northwest side of the volcano, while tephras were dispersed northwest and north-northeast. This sudden eruption prompted the local Ministry of Environment to request cooperation with Italian scientists in order to improve the monitoring of the volcano during this unrest. A joint force made up of an Italian team from the Istituto Nazionale di Geofisica e Vulcanologia and a local team from the Ministerio de Medio Ambiente y Recursos Naturales was organized to enhance the volcanological, geophysical and geochemical monitoring system to study the evolution of the phenomenon during the crisis. The joint team quickly installed a multi-parametric mobile network comprising seismic, geodetic and geochemical sensors, designed to cover all the volcano flanks from the lowest to the highest possible altitudes, and a thermal camera. To simplify the logistics for a rapid installation and for security reasons, some sensors were co-located into multi-parametric stations. Here, we describe the prompt design and installation of the geodetic monitoring network, the processing and results. The installation of a new ground deformation network can be considered an important result by itself, while the detection of some crucial deforming areas is very significant information, useful for dealing with future threats and for further studies on this poorly monitored volcano.
33
Krotenok, A. Yu, D. M. Nikolaeva, and A. M. Nikolaeva. "The Calculation Of The Normal Height Of The State Geodetic Network Point Based On The Local Quasigeoid Model." IOP Conference Series: Earth and Environmental Science 272 (June 21, 2019): 022111. http://dx.doi.org/10.1088/1755-1315/272/2/022111.
Full text
34
Savanović, Marija, Rajko Savanović, Toša Ninkov, and Igor Sabados. "Proposed design of local 2d geodetic network for the construction of the tunnel part of the Belgrade metro." Geodetski vestnik 59, no. 03 (2015): 564–76. http://dx.doi.org/10.15292/geodetski-vestnik.2015.03.564-576.
Full text
35
Pécontal, Emmanuel. "Les mires méridiennes lointaines de l’Observatoire de Lyon : Recherches bibliographiques, archivistiques et archéologiques." Nuncius 28, no. 2 (2013): 276–312. http://dx.doi.org/10.1163/18253911-02802002.
Full textAbstract:
The first argument set out in 1877 by the Parisian astronomer Charles André, founder of the Observatoire de Lyon, to justify the establishment of an astronomical institute in Saint-Genis-Laval was the fact that it offered the opportunity to install remote marks along its meridian. André had used this argument three years before to reject another site selected by a local committee. However, at that time remote meridian marks had been abandoned by most astronomers in favour of close ones. We have conducted field research to discover the remains of these marks, as well as to seek evidence – both in the literature and in archives – of their use. This investigation shows that the argument for remote marks was in fact driven by geodetic considerations. The choice of Saint-Genis-Laval was actually made by geodesists of the Dépôt Général de la Guerre and its director, François Perrier, who wanted to institute new observatories in Province as key points in the primary geodetic network of France.
36
Gökdaş, Ömer, and M. Tevfik Özlüdemir. "A Variance Model in NRTK-Based Geodetic Positioning as a Function of Baseline Length." Geosciences 10, no. 7 (July 9, 2020): 262. http://dx.doi.org/10.3390/geosciences10070262.
Full textAbstract:
This study examines the effect of baseline length on accuracy and precision in Network Real-Time Kinematic (NRTK) positioning and develops an experimental mathematical model to express this effect. The study also measures the performances of the Flaechen Korrektur Parameter (FKP) and Virtual Reference Stations (VRS) methods at different baseline lengths. The study makes use of the stations that form two Continuously Operating Reference Station (CORS) networks, one of which is local and the other national. Calculations were made to perform various geodetic operations, such as datum transformations between the two networks, identifications of positional velocities, and epoch shifting. BERNESE (v5.2) software was used to identify coordinate values assumed to be true based on International GNSS Service (IGS) products. No significant changes were observed in the RMSE values in baseline lengths of up to 40 km. In contrast, an average linear correlation of 69.2% was determined between precision and baseline length. Measurements were evaluated and tested using the variance model created as a function of the baseline length, in line with the aims of the study, and the results were found to be consistent. Moreover, in an examination of the Root Mean Square Error (RMSE) and precision values of the FKP and VRS measurements, no significant differences were observed. The mean differences were at the millimetre level.
37
Ziggah, Yao Yevenyo, Hu Youjian, Alfonso Rodrigo Tierra, and Prosper Basommi Laari. "Coordinate Transformation between Global and Local Datums Based on Artificial Neural Network with K-Fold Cross-Validation: A Case Study, Ghana." Earth Sciences Research Journal 23, no. 1 (January 1, 2019): 67–77. http://dx.doi.org/10.15446/esrj.v23n1.63860.
Full textAbstract:
The popularity of Artificial Neural Network (ANN) methodology has been growing in a wide variety of areas in geodesy and geospatial sciences. Its ability to perform coordinate transformation between different datums has been well documented in literature. In the application of the ANN methods for the coordinate transformation, only the train-test (hold-out cross-validation) approach has usually been used to evaluate their performance. Here, the data set is divided into two disjoint subsets thus, training (model building) and testing (model validation) respectively. However, one major drawback in the hold-out cross-validation procedure is inappropriate data partitioning. Improper split of the data could lead to a high variance and bias in the results generated. Besides, in a sparse dataset situation, the hold-out cross-validation is not suitable. For these reasons, the K-fold cross-validation approach has been recommended. Consequently, this study, for the first time, explored the potential of using K-fold cross-validation method in the performance assessment of radial basis function neural network and Bursa-Wolf model under data-insufficient situation in Ghana geodetic reference network. The statistical analysis of the results revealed that incorrect data partition could lead to a false reportage on the predictive performance of the transformation model. The findings revealed that the RBFNN and Bursa-Wolf model produced a transformation accuracy of 0.229 m and 0.469 m, respectively. It was also realised that a maximum horizontal error of 0.881 m and 2.131 m was given by the RBFNN and Bursa-Wolf. The obtained results per the cadastral surveying and plan production requirement set by the Ghana Survey and Mapping Division are applicable. This study will contribute to the usage of K-fold cross-validation approach in developing countries having the same sparse dataset situation like Ghana as well as in the geodetic sciences where ANN users seldom apply the statistical resampling technique.
38
Šarlah, Nikolaj, Tomaž Podobnikar, Domen Mongus, Tomaž Ambrožič, and Branko Mušič. "Kinematic GPR-TPS Model for Infrastructure Asset Identification with High 3D Georeference Accuracy Developed in a Real Urban Test Field." Remote Sensing 11, no. 12 (June 19, 2019): 1457. http://dx.doi.org/10.3390/rs11121457.
Full textAbstract:
This paper describes in detail the development of a ground-penetrating radar (GPR) model for the acquisition, processing and visualisation of underground utility infrastructure (UUI) in a controlled environment. The initiative was to simulate a subsurface urban environment through the construction of regional road, local road and pedestrian pavement in real urban field/testing pools (RUTPs). The RUTPs represented a controlled environment in which the most commonly used utilities were installed. The accuracy of the proposed kinematic GPR-TPS (terrestrial positioning system) model was analysed using all the available data about the materials, whilst taking into account the thickness of the pavement as well as the materials, dimensions and 3D position of the UUI as given reference values. To determine the reference 3D position of the UUI, a terrestrial geodetic surveying method based on the established positional and height geodetic network was used. In the first phase of the model, the geodetic network was used as a starting point for determining the 3D position of the GPR antenna with the efficient kinematic GPR surveying setup using a GPR and self-tracking (robotic) TPS. In the second phase, GPR-TPS system latency was quantified by matching radargram pairs with a set of fidelity measures based on a correlation coefficient and mean squared error. This was followed by the most important phase, where, by combining sets of “standard” processing routines of GPR signals with the support of advanced algorithms for signal processing, UUI were interpreted and visualised semi-automatically. As demonstrated by the results, the proposed GPR model with a kinematic GPR-TPS surveying setup for data acquisition is capable of achieving an accuracy of less than ten centimetres.
39
Weiss, Gabriel, Karol Bartoš, Slavomír Labant, Juraj Gašinec, Erik Weiss, Ladislav Mixtaj, Roland Weiss, and Jozef Zuzik. "The identification of incorrectly determined new points in established 2D Local Geodetic Network during deformation monitoring for environmental protection." Journal of Cleaner Production 170 (January 2018): 789–96. http://dx.doi.org/10.1016/j.jclepro.2017.09.179.
Full text
40
Mavrodiev, S. Cht. "On the reliability of the geomagnetic quake as a short time earthquake's precursor for the Sofia region." Natural Hazards and Earth System Sciences 4, no. 3 (June 21, 2004): 433–47. http://dx.doi.org/10.5194/nhess-4-433-2004.
Full textAbstract:
Abstract. The local "when" for earthquake prediction is based on the connection between geomagnetic "quakes" and the next incoming minimum or maximum of tidal gravitational potential. The probability time window for the predicted earthquake is for the tidal minimum approximately ±1 day and for the maximum ±2 days. The preliminary statistic estimation on the basis of distribution of the time difference between occurred and predicted earthquakes for the period 2002-2003 for the Sofia region is given. The possibility for creating a local "when, where" earthquake research and prediction NETWORK is based on the accurate monitoring of the electromagnetic field with special space and time scales under, on and over the Earth's surface. The periodically upgraded information from seismic hazard maps and other standard geodetic information, as well as other precursory information, is essential.
41
Pham, Khanh Quoc. "Application of statistical test on determining the unstable points in the basic network of horizontal displacement monitoring." Journal of Mining and Earth Sciences 62, no. 1 (February 28, 2021): 35–41. http://dx.doi.org/10.46326/jmes.2021.62(1).05.
Full textAbstract:
The paper represents the hypothesis test method that can determine the instability control points of the reference network in the displacement of construction. Regarding data processing in displacement monitoring, the detection and modification for instability points is an important task because this affects the computation of the displacement of monitoring points. This method has been applied in many countries over the world but not in Vietnam, and it is processed through two steps including the global statistics test and local statistics test. The global statistics test is to identify whether a control point is stable or not. The local statistics test based on the division of groups is to find the unstable control points exactly. Experimental computation is carried out in two monitoring cycles at Hoa Binh hydroelectric plant. In this experiment, this algorithm detected two unstable points among six control points. This result is in agreement with the result that is solved by Vietnam’s construction standard of TCVN 9399:2012. In conclusion, the hypothesis test method completely can apply in real geodetic production in Vietnam.
42
Alves, D., L. Dalbelo, J. Monico, and M. Shimabukuro. "First Brazilian Real Time Network DGPS through the Internet: Development, Application and Availability Analyses." Journal of Geodetic Science 2, no. 1 (January 1, 2012): 1–7. http://dx.doi.org/10.2478/v10156-011-0018-7.
Full textAbstract:
First Brazilian Real Time Network DGPS through the Internet: Development, Application and Availability AnalysesThe Global Positioning System (GPS) is widely used by the civil community. Differential GPS (DGPS) was developed to provide better accuracy than autonomous GPS. The DGPS concept is based on the high correlation of errors due to atmospheric effects, satellite clocks and orbits. However, as the baseline grows, its efficiency decreases because the error correlation is reduced. This limitation can be handled by using a reference station network and applying the network DGPS concept (called NDGPS). In this paper, the goal is to present aspects related to the development and application of NDGPS in real time at the São Paulo state network in Brazil. The NDGPS corrections were computed from data received via the Internet using NTRIP (Networked Transport of RTCM via Internet Protocol). Our implementation was based on BNC (BKG Ntrip Client) software. NDGPS provided RMS improvements of up to 59% in horizontal components and 31% in vertical components when compared to DGPS. The availability of the system, the first of this nature in Brazil, was also analyzed within the context of the SP State GNSS Network, located in the southeastern region of Brazil. The results also serve as an indication of the quality of local internet infrastructure for using in geodetic positioning.
43
Bosse, Stefan. "Incremental Distributed Learning with JavaScript Agents for Earthquake and Disaster Monitoring." International Journal of Distributed Systems and Technologies 8, no. 4 (October 2017): 34–53. http://dx.doi.org/10.4018/ijdst.2017100103.
Full textAbstract:
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.
44
Lamparska, Marzena, and Mirosław Danch. "“Sucha Góra” (“Trockenberg”)—The Triangulation Point Doomed to Be Forgotten?" Land 10, no. 2 (January 23, 2021): 109. http://dx.doi.org/10.3390/land10020109.
Full textAbstract:
The current study documents the importance of research on preserved artifacts which were previously used to take measurements of the Earth, and their importance for cultural heritage. The article reviewed the available source documents presenting the history of the astrogeodetic control point of Sucha Góra-Trockenberg as a monument of the first order triangulation network, preserved in cartographic materials and as the starting point of local geodetic networks, used in mining until 2000 in the so-called Upper Silesian Coal Basin, located in the territory of Poland and the Czech Republic. In order to determine the history of the triangulation work and the dates that the geographic coordinates of the peak were determined, field journals and other available materials were analyzed. The interesting location of this astrogeodetic control point, being in the vicinity of a UNESCO site, as well as its location in a forest and park complex, justify undertaking activities related to the conservation and promotion of this cultural heritage site.
45
Godah, Walyeldeen, Jagat Dwipendra Ray, Malgorzata Szelachowska, and Jan Krynski. "The Use of National CORS Networks for Determining Temporal Mass Variations within the Earth’s System and for Improving GRACE/GRACE-FO Solutions." Remote Sensing 12, no. 20 (October 15, 2020): 3359. http://dx.doi.org/10.3390/rs12203359.
Full textAbstract:
Temporal mass variations within the Earth’s system can be detected on a regional/global scale using GRACE (Gravity Recovery and Climate Experiment) and GRACE Follow-On (GRACE-FO) satellite missions’ data, while GNSS (Global Navigation Satellite System) data can be used to detect those variations on a local scale. The aim of this study is to investigate the usefulness of national GNSS CORS (Continuously Operating Reference Stations) networks for the determination of those temporal mass variations and for improving GRACE/GRACE-FO solutions. The area of Poland was chosen as a study area. Temporal variations of equivalent water thickness ΔEWT and vertical deformations of the Earth’s surface Δh were determined at the sites of the ASG-EUPOS (Active Geodetic Network of the European Position Determination System) CORS network using GRACE/GRACE-FO-based GGMs and GNSS data. Moreover, combined solutions of ΔEWT were developed by combining ΔEWT obtained from GNSS data with the corresponding ones determined from GRACE satellite mission data. Strong correlations (correlation coefficients ranging from 0.6 to 0.9) between detrended Δh determined from GRACE/GRACE-FO satellite mission data and the corresponding ones from GNSS data were observed at 93% of the GNSS stations investigated. Furthermore, for the determination of temporal mass variations, GNSS data from CORS network stations provide valuable information complementary to GRACE satellite mission data.
46
Ziggah, Yao Yevenyo, Hu Youjian, Prosper Basommi Laari, and Zhenyang Hui. "NOVEL APPROACH TO IMPROVE GEOCENTRIC TRANSLATION MODEL PERFORMANCE USING ARTIFICIAL NEURAL NETWORK TECHNOLOGY." Boletim de Ciências Geodésicas 23, no. 1 (March 2017): 213–33. http://dx.doi.org/10.1590/s1982-21702017000100014.
Full textAbstract:
Abstract: Geocentric translation model (GTM) in recent times has not gained much popularity in coordinate transformation research due to its attainable accuracy. Accurate transformation of coordinate is a major goal and essential procedure for the solution of a number of important geodetic problems. Therefore, motivated by the successful application of Artificial Intelligence techniques in geodesy, this study developed, tested and compared a novel technique capable of improving the accuracy of GTM. First, GTM based on official parameters (OP) and new parameters determined using the arithmetic mean (AM) were applied to transform coordinate from global WGS84 datum to local Accra datum. On the basis of the results, the new parameters (AM) attained a maximum horizontal position error of 1.99 m compared to the 2.75 m attained by OP. In line with this, artificial neural network technology of backpropagation neural network (BPNN), radial basis function neural network (RBFNN) and generalized regression neural network (GRNN) were then used to compensate for the GTM generated errors based on AM parameters to obtain a new coordinate transformation model. The new implemented models offered significant improvement in the horizontal position error from 1.99 m to 0.93 m.
47
Florentine, Caitlyn, Joel Harper, Daniel Fagre, Johnnie Moore, and Erich Peitzsch. "Local topography increasingly influences the mass balance of a retreating cirque glacier." Cryosphere 12, no. 6 (June 20, 2018): 2109–22. http://dx.doi.org/10.5194/tc-12-2109-2018.
Full textAbstract:
Abstract. Local topographically driven processes – such as wind drifting, avalanching, and shading – are known to alter the relationship between the mass balance of small cirque glaciers and regional climate. Yet partitioning such local effects from regional climate influence has proven difficult, creating uncertainty in the climate representativeness of some glaciers. We address this problem for Sperry Glacier in Glacier National Park, USA, using field-measured surface mass balance, geodetic constraints on mass balance, and regional climate data recorded at a network of meteorological and snow stations. Geodetically derived mass changes during 1950–1960, 1960–2005, and 2005–2014 document average mass change rates during each period at −0.22 ± 0.12, −0.18 ± 0.05, and −0.10 ± 0.03 m w.e. yr−1, respectively. A correlation of field-measured mass balance and regional climate variables closely (i.e., within 0.08 m w.e. yr−1) predicts the geodetically measured mass loss from 2005 to 2014. However, this correlation overestimates glacier mass balance for 1950–1960 by +1.20 ± 0.95 m w.e. yr−1. Our analysis suggests that local effects, not represented in regional climate variables, have become a more dominant driver of the net mass balance as the glacier lost 0.50 km2 and retreated further into its cirque.
48
Hofmann, S., and C. Brenner. "ACCURACY ASSESSMENT OF MOBILE MAPPING POINT CLOUDS USING THE EXISTING ENVIRONMENT AS TERRESTRIAL REFERENCE." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 3, 2016): 601–8. http://dx.doi.org/10.5194/isprsarchives-xli-b1-601-2016.
Full textAbstract:
Mobile mapping data is widely used in various applications, what makes it especially important for data users to get a statistically verified quality statement on the geometric accuracy of the acquired point clouds or its processed products. The accuracy of point clouds can be divided into an absolute and a relative quality, where the absolute quality describes the position of the point cloud in a world coordinate system such as WGS84 or UTM, whereas the relative accuracy describes the accuracy within the point cloud itself. Furthermore, the quality of processed products such as segmented features depends on the global accuracy of the point cloud but mainly on the quality of the processing steps. Several data sources with different characteristics and quality can be thought of as potential reference data, such as cadastral maps, orthophoto, artificial control objects or terrestrial surveys using a total station. In this work a test field in a selected residential area was acquired as reference data in a terrestrial survey using a total station. In order to reach high accuracy the stationing of the total station was based on a newly made geodetic network with a local accuracy of less than 3 mm. The global position of the network was determined using a long time GNSS survey reaching an accuracy of 8 mm. Based on this geodetic network a 3D test field with facades and street profiles was measured with a total station, each point with a two-dimensional position and altitude. In addition, the surface of poles of street lights, traffic signs and trees was acquired using the scanning mode of the total station. <br><br> Comparing this reference data to the acquired mobile mapping point clouds of several measurement campaigns a detailed quality statement on the accuracy of the point cloud data is made. Additionally, the advantages and disadvantages of the described reference data source concerning availability, cost, accuracy and applicability are discussed.
49
Hofmann, S., and C. Brenner. "ACCURACY ASSESSMENT OF MOBILE MAPPING POINT CLOUDS USING THE EXISTING ENVIRONMENT AS TERRESTRIAL REFERENCE." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 3, 2016): 601–8. http://dx.doi.org/10.5194/isprs-archives-xli-b1-601-2016.
Full textAbstract:
Mobile mapping data is widely used in various applications, what makes it especially important for data users to get a statistically verified quality statement on the geometric accuracy of the acquired point clouds or its processed products. The accuracy of point clouds can be divided into an absolute and a relative quality, where the absolute quality describes the position of the point cloud in a world coordinate system such as WGS84 or UTM, whereas the relative accuracy describes the accuracy within the point cloud itself. Furthermore, the quality of processed products such as segmented features depends on the global accuracy of the point cloud but mainly on the quality of the processing steps. Several data sources with different characteristics and quality can be thought of as potential reference data, such as cadastral maps, orthophoto, artificial control objects or terrestrial surveys using a total station. In this work a test field in a selected residential area was acquired as reference data in a terrestrial survey using a total station. In order to reach high accuracy the stationing of the total station was based on a newly made geodetic network with a local accuracy of less than 3 mm. The global position of the network was determined using a long time GNSS survey reaching an accuracy of 8 mm. Based on this geodetic network a 3D test field with facades and street profiles was measured with a total station, each point with a two-dimensional position and altitude. In addition, the surface of poles of street lights, traffic signs and trees was acquired using the scanning mode of the total station. <br><br> Comparing this reference data to the acquired mobile mapping point clouds of several measurement campaigns a detailed quality statement on the accuracy of the point cloud data is made. Additionally, the advantages and disadvantages of the described reference data source concerning availability, cost, accuracy and applicability are discussed.
50
Xing, Zhizhong, Shuanfeng Zhao, Wei Guo, Xiaojun Guo, and Yuan Wang. "Processing Laser Point Cloud in Fully Mechanized Mining Face Based on DGCNN." ISPRS International Journal of Geo-Information 10, no. 7 (July 13, 2021): 482. http://dx.doi.org/10.3390/ijgi10070482.
Full textAbstract:
Point cloud data can accurately and intuitively reflect the spatial relationship between the coal wall and underground fully mechanized mining equipment. However, the indirect method of point cloud feature extraction based on deep neural networks will lose some of the spatial information of the point cloud, while the direct method will lose some of the local information of the point cloud. Therefore, we propose the use of dynamic graph convolution neural network (DGCNN) to extract the geometric features of the sphere in the point cloud of the fully mechanized mining face (FMMF) in order to obtain the position of the sphere (marker) in the point cloud of the FMMF, thus providing a direct basis for the subsequent transformation of the FMMF coordinates to the national geodetic coordinates with the sphere as the intermediate medium. Firstly, we completed the production of a diversity sphere point cloud (training set) and an FMMF point cloud (test set). Secondly, we further improved the DGCNN to enhance the effect of extracting the geometric features of the sphere in the FMMF. Finally, we compared the effect of the improved DGCNN with that of PointNet and PointNet++. The results show the correctness and feasibility of using DGCNN to extract the geometric features of point clouds in the FMMF and provide a new method for the feature extraction of point clouds in the FMMF. At the same time, the results provide a direct early guarantee for analyzing the point cloud data of the FMMF under the national geodetic coordinate system in the future. This can provide an effective basis for the straightening and inclining adjustment of scraper conveyors, and it is of great significance for the transparent, unmanned, and intelligent mining of the FMMF.