scholarly journals Influence of the Datum Definition on the Accuracy of Horizontal Geodetic Control Networks for Engineering Objects

2019 ◽  
Vol 8 (3) ◽  
pp. 99-106
Author(s):  
Nedim Tuno ◽  
Admir Mulahusić ◽  
Jusuf Topoljak
Keyword(s):  
Geodetic Network ◽  
Control Points ◽  
Engineering Structures ◽  
Control Networks ◽  
Geometrical Distribution ◽  
Quality Of Control ◽  
Design And Implementation ◽  
Triangulation Network ◽  
Geodetic Control

For the construction of various civil engineering structures, particular care should be taken in the perspective of geodetic control. Therefore, the design and implementation of the geodetic network deserves special attention. This paper is focused on various aspects of datum definitions for tested micro-triangulation network. It was shown that the geometrical distribution of datum points in a minimally constrained solution has a great impact on the accuracy of the geodetic network. Estimates of the accuracies of individual station y-x coordinates, error circles and error ellipses, obtained by free adjustment, where the datum selection was independent of errors in fixed coordinates, revealed much better quality of control points.

scholarly journals GEOMETRIC ASPECTS EVALUATION OF GNSS CONTROL NETWORK FOR DEFORMATION MONITORING IN THE JATIGEDE DAM REGION

2019 ◽  
Vol 15 (2) ◽  
pp. 167
Author(s):  
Made Ditha Ary Sanjaya ◽  
T. Aris Sunantyo ◽  
Nurrohmat Widjajanti
Keyword(s):  
Least Squares ◽  
Deformation Monitoring ◽  
Network Configuration ◽  
Control Networks ◽  
Quality Of Control ◽  
Least Squares Adjustment ◽  
Standard Deviations ◽  
Dam Deformation ◽  
Gnss Networks

Many factors led to dam construction failure so that deformation monitoring activities is needed in the area of the dam. Deformation monitoring is performed in order to detect a displacement at the control points of the dam. Jatigede Dam deformation monitoring system has been installed and started to operate, but there has been no evaluation of the geometry quality of control networks treated with IGS points for GNSS networks processing. Therefore, this study aims to evaluate the geometric quality of GNSS control networks on deformation monitoring of Jatigede Dam area. This research data includes the GNSS measurements of five CORS Jatigede Dam stations (R01, GG01, GCP04, GCP06, and GCP08) at doy 233 with network configuration scenarios of 12 IGS points on two quadrants (jat1), three quadrants (jat2), and four quadrants (jat3 and jat4). GNSS networks processing was done by GAMIT to obtain baseline vectors, followed by network processing usingparameter method of least squares adjustment. Networks processing with least squares adjustment aims to determine the most optimal  by precision and reliability criterion. Results of this study indicate that network configuration with 12 IGS stations in the two quadrants provides the most accurate coordinates of CORS dam stations. Standard deviations value of CORS station given by jat1 configuration are in the range of 2.7 up to 4.1 cm in X-Z components, whereas standard deviations in the Y component are in the range 5.8 up to 6.9 cm. An optimization assessment based on network strength, precision, and reliability factors shows optimum configuration by jat1.

scholarly journals Analysis of technical condition of footbridges over the railways in danger of collapse

2019 ◽  
Vol 284 ◽  
pp. 01001
Author(s):  
Ryszard Chmielewski ◽  
Aleksandra Bąk
Keyword(s):  
Significant Influence ◽  
Technical Condition ◽  
Engineering Structures ◽  
Design And Implementation ◽  
Construction Design ◽  
Rainwater Management ◽  
Structural Failures ◽  
Periodic Inspections

The article presents issues related to the maintenance of small engineering structures, such as footbridges over railways. These types of objects, usually are simple both in structure and construction. Design and construction errors usually, do not endanger the safety of the structure, although unrepaired ones may shorten the usability of the object. Particular attention should be paid to the elements of drainage, because effective rainwater management has significant influence to engineering structures usability. Regular inspections should ensure the operation of facilities that allow to avoid excessive deterioration of functional properties or maintaining objects in a proper technical and aesthetic condition. Structural collapses, that took place between 2014 and 2017 constitute only 2.85% [3], which indicates the improvement of quality of both design and implementation. However, it should be noted that maintenance errors are the second cause of structural failures. Therefore, it is necessary to emphasize crucial role of people performing periodic inspections of buildings, whose recommendations should be adhered and implemented by facility managers. The article presents examples of two footbridges over railways, that due to improper maintenance were excluded from use. Further operation of these footbridges threatened with construction collapse.

scholarly journals Designing Control Points in UAV-Photogrammetry Mapping Using GNSS Concept to Produce Land Use Map (Case Study: Ciwidey Village, Bandung Regency, Indonesia)

2019 ◽  
Vol 94 ◽  
pp. 01020
Author(s):  
Sadikin Hendriatiningsih ◽  
Asep Y. Saptari ◽  
Sudarman ◽  
Ratri Widyastuti ◽  
Putri Rahmadani
Keyword(s):  
Observation Time ◽  
Baseline Length ◽  
Control Points ◽  
Quality Of Control ◽  
Field Situation ◽  
American Society ◽  
Time Accuracy ◽  
And Control

Production of orhtophoto maps from UAV-photogrammetry method depend on aerial data and control points that are measured by GNSS method. Quality control of orhtophoto maps need comparison coordinate from Check Points and orthophoto maps coordinate to calculate the Root Mean Square Error (RMSE). So that, quality of control points is important in aerial data processing. In this research, baseline length, observation time, measurement method, and area characteristics will be discussed based on the GNSS concept to fulfill the accuracy standard of control points from the American Society of Photogrammetry and Remote Sensing (ASPRS). The shorter baseline length, and the loner observation time, accuracy should be increase significantly, but it depends on the field situation and the accuracy required for the user. After all, the result of this research is to obtain control points design based on GNSS concept in Ciwidey Village, Bandung Regency

scholarly journals GIScience Theory Based Assessment of Spatial Disparity of Geodetic Control Points Location

2020 ◽  
Vol 9 (3) ◽  
pp. 148
Author(s):  
Elzbieta Bielecka ◽  
Krzysztof Pokonieczny ◽  
Sylwia Borkowska
Keyword(s):  
Nearest Neighbor ◽  
Geodetic Network ◽  
Control Points ◽  
Outlier Analysis ◽  
Geodetic Networks ◽  
Land Administration ◽  
Ex Post ◽  
Spatial Cluster Analysis ◽  
Geodetic Control ◽  
Application Fields

Geodetic networks provide a spatial reference framework for the positioning of any geographical feature in a common and consistent way. An even spatial distribution of geodetic control points assures good quality for subordinate surveys in mapping, cadaster, engineering activities, and many other land administration-oriented applications. We investigate the spatial pattern of geodetic control points based on GIScience theory, especially Tobler’s Laws in Geography. The study makes contributions in both the research and application fields. By utilizing Average Nearest Neighbor, multi-distance spatial cluster analysis, and cluster and outlier analysis, it introduces the comprehensive methodology for ex post analysis of geodetic control points’ spatial patterns as well as the quantification of geodetic networks’ uniformity to regularly dense and regularly thinned. Moreover, it serves as a methodological resource and reference for the Head Office of Geodesy and Cartography, not only the maintenance, but also the further densification or modernization the geodetic network in Poland. Furthermore, the results give surveyors the ability to quickly assess the availability of geodetic points, as well as identify environmental obstacles that may hamper measurements. The results show that the base geodetic control points are evenly dispersed (one point over 50 sq. km), however they tend to cluster slightly in urbanized areas and forests (1.3 and 1.4 points per sq. km, respectively).

scholarly journals Influence of distance, geometry and number of control stations on quality of local geodetic networks for the purpose of georeferencing of rural properties

2014 ◽  
Vol 34 (2) ◽  
pp. 311-321 ◽  
Author(s):  
David Luciano Rosalen
Keyword(s):  
Statistical Tests ◽  
Distance Geometry ◽  
Geodetic Network ◽  
Maximum Distance ◽  
Baseline Length ◽  
Technical Standard ◽  
Geodetic Networks ◽  
Geodetic Control

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.

Applications of Statistical Characteristics of Geodetic Networks

1974 ◽  
Vol 28 (5) ◽  
pp. 702-708
Author(s):  
L. A. Gale
Keyword(s):  
Observational Data ◽  
Geodetic Network ◽  
Statistical Information ◽  
Statistical Characteristics ◽  
Geodetic Networks ◽  
Control File ◽  
Geodetic Control ◽  
Inner Constraint

Numerous statistics that can be obtained from the processing of the observations and the adjustment of a geodetic network can be used to assess the quality of the network and the observational data. The processes used for assessment and planning depend on the needs and the capabilities of the user. Statistical information derived from nonsingular vis-à-vis singular (“inner-constraint”) adjustments is discussed. Standards for the characterization of the quality of networks are reviewed. Suggestions are made on the type of information that should be directly available from a geodetic control file.

scholarly journals Analysis of technological schemes for creating a geodetic control at the industrial site

2021 ◽  
Vol 249 ◽  
pp. 366-376
Author(s):  
Georgii Ustavich ◽  
Anatolii Nevolin ◽  
Vladimir Padve ◽  
Valerii Salnikov ◽  
Anton Nikonov
Keyword(s):  
Initial Data ◽  
Measurement Errors ◽  
Geodetic Network ◽  
Industrial Site ◽  
Building Structures ◽  
Engineering Structures ◽  
Total Station ◽  
Geodetic Control ◽  
Under Construction ◽  
Mean Square Errors

The article highlights the issues of creating with the necessary accuracy a planned control on the industrial site of the engineering structures under construction using satellite technologies and total stations. Depending on the design features of the engineering structures under construction, as well as the technological scheme for the installation of building constructions and industrial equipment, various schemes for creating such control are considered, based on the application of the inverse linear-angular notch. Errors in the source data are one of the main errors that affect the accuracy of geodetic constructions, including the solution of the inverse linear-angular notch. When creating a geodetic network in several stages, the errors of the initial data of the first stage affect the values of the root-mean-square errors (RMS) of determining the position of the second stage points, the errors of which affect the value of the RMS of the position of the third stage points, etc. The reason for their occurrence is the errors of geodetic measurements that occur at each stage of control creating, as well as the stability violation of the points during the production of excavation, construction and installation works. When determining the coordinates of a separate project point at the stage of its removal in-situ by a total station, the entire network is not equalized in the vast majority of cases, and the coordinates of the starting points to which the total station is oriented are considered error-free. As a result, the RMS determination of the points coordinates of the control network or the removal of the design points of the elements of building structures and equipment will also be considered satisfying the requirements, i.e. the measurement accuracy will be artificially overestimated and will not correspond to the actual one obtained. This is due to the fact that the accumulation of errors in the initial data is not taken into account when the number of steps (stages) of control creating increases. The purpose of this work is to analyze the influence of measurement errors and initial data when creating a geodetic control on an industrial site by several stages of its construction based on inverse linear-angular notches and a priori estimation of the accuracy of the determined points position.

scholarly journals Determination Of Horizontal Geodetic Control Networks For Engineering Objects Using Optoelectronic Techniques

2015 ◽  
Vol 98 (1) ◽  
pp. 39-51 ◽  
Author(s):  
Kazimierz Ćmielewski ◽  
Janusz Kuchmister ◽  
Piotr Gołuch ◽  
Izabela Wilczyńska ◽  
Krzysztof Kowalski
Keyword(s):  
Measurement Accuracy ◽  
Control Points ◽  
Control Networks ◽  
Laboratory Conditions ◽  
Optoelectronic Method ◽  
Geodetic Control ◽  
And Control ◽  
Horizontal Control

AbstractThe correctness of the geodetic service of an engineering object not seldom requires designing, alignment or renewing of geodetic situational control points. Building robots often cause that fixed situational control points are partly or completely inaccessible. For setting the position of these control points, there is worked out the methodology using the optoelectronic method. The prepared set of tools realizes the method’s assumptions and enables to determine the sides and control points based on the set of laser planes. In this article there is presented the innovative set of geodetic equipment for fixing horizontal control points. The presented set has been experimentally tested under laboratory conditions taking its functionality, operation range and applied accuracy into account. The measurement accuracy of the set of tools, resulting from identification of the energetic centres of laser planes’ edges, visualizing the sides of geodetic control networks, is within the range of ±0.02mm - ±0.05mm. There were also discussed exemplary versions of shapes and structures of horizontal geodetic control networks (regular and irregular), which are possible to be fixed with the use of the constructed set of tools.

scholarly journals SATELLITE POSITIONING BASED EXTENSION OF GEODETIC REFERENCE NETWORK TO SUPPORT GEOSPATIAL APPLICATIONS

2018 ◽  
Keyword(s):  
Control Point ◽  
Geodetic Network ◽  
Computational Techniques ◽  
Reference Network ◽  
Control Points ◽  
Positioning Systems ◽  
Satellite Positioning ◽  
Geodetic Control ◽  
Office Software ◽  
Central Kenya

A national geodetic network provides the fundamental framework that enables attainment of high accuracy geodetic measurements. It plays a key role in the efficiency and reliability of operations in land surveying, mapping, remote sensing, Geographic Information System, engineering surveying and other related applications. The geodetic framework provides the basis for integrating all mapping and survey activities. About eighty per cent of the primary geodetic control points in Kenya, established in the early twentieth century, have been destroyed. This has resulted in expensive and time consuming operations and processes for geospatial professionals and scientists. This situation is particularly worse in central Kenya, hence the need to extend the geodetic control by establishing more control points on secure and accessible sites for use by geospatial professionals and scientists in a wide variety of applications. In this study, modern satellite positioning techniques were utilised to extend geodetic reference network in central Kenya. Existing geodetic control points were used to facilitate establishment of new geodetic control points distributed within the region. Field observations were carried out using Global Positioning System. The raw data were downloaded, edited, processed and adjusted using Leica Geo-Office software. The resulting final adjusted coordinates had a maximum standard deviation of 2cm and 5cm on horizontal and vertical coordinates respectively, and a general loop misclosure of less than one part per million. The results showed that the quality of established control point positions was high, and demonstrated the efficient extension of geodetic control network using modern satellite positioning systems and efficient computational techniques in situations such as the ones currently prevailing in central Kenya.

scholarly journals Functionality and reliability of horizontal control net (Poland)

2020 ◽  
Vol 12 (1) ◽  
pp. 668-677
Author(s):  
Bogdan Wolski ◽  
Grzegorz Granek
Keyword(s):  
Process Model ◽  
Standard Procedure ◽  
Operating Time ◽  
Control Network ◽  
Control Points ◽  
Destruction Process ◽  
Control Networks ◽  
Geodetic Control ◽  
The Impact ◽  
Horizontal Control

AbstractHorizontal control networks established with monuments are functional if the conditions related to the number of control points, their density, condition and stability of coordinates are met. For functionality defined in those terms, deterministic accuracy characteristics are of little use. The subject matter discussed herein includes the two key features of geodetic control points, i.e., usability and stability. Due to the varying properties of those variables and the impact of the operating time of the system, there is no alternative to reliability-based approach in developing the functionality model. The measures of functionality and the procedures of data acquisition for developing the model of the control network destruction process have been defined. The solution presented herein is relevant for geodetic practice, providing a standard procedure for defining the time frame and the scope of the control network upgrading. The identified destruction process model optimizes this task assuming critical states expressed by the functionality probability. The applied approach is an example of the reliability theory-based approach typical for engineering. The issue of simulating the destruction process is illustrated with the results of the tests of class 3 control networks conducted in Kielce and Lodz regions in Poland. As a result of the tests, the characteristic properties of the control network destruction process have been identified. It was also shown how the patterns of usability and accuracy of the geodetic control points are relevant on the stage of implementing investment project tasks.

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