• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.10a
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• pp.97-101
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• 2003

Among GPS methods, first of all, we used RTK GPS to analyze the precision of monitoring and then on the basis of it, we developed a monitoring system using RTK GPS when we measured the behavior of main tower of a suspension bridge by using RTK GPS method and IMU, which was an inertia navigation system. Comparing a deviation between observation value using IMU and RTK GPS, X axis was 1mm, Y axis 1mm and Z axis 2.21mm. It turned out that it was possible to monitor and measure structures by using RTK GPS method. Besides, in order to manage the structures and prevent their disaster, the transformed monitoring, which used dynamic RTK GPS measurement method, was applied in real time. It was verified that it could be used as transformed monitoring measurement method for massive structures.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.2
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• pp.179-185
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• 2016

In this study, the RDII predictions were compared using two methodologies, i.e., the RTK-based and regression methods. Long-term (1/1/2011~12/31/2011) monitoring data, which consists of 10-min interval streamflow and the amount of precipitation, were collected at the domestic study area (1.36 km2 located in H county), and used for the construction of the RDII prediction models. The RTK method employs super position of tri-triangles, and each triangle (called, unit hydrograph) is defined by three parameters (i.e., R, T and K) determined/optimized using Genetic Algorithm (GA). In regression method, the MovingAverage (MA) filtering was used for data processing. Accuracies of RDII predictions from these two approaches were evaluated by comparing the root mean square error (RMSE) values from each model, in which the values were calculated to 320.613 (RTK method) and 420.653 (regression method), respectively. As a results, the RTK method was found to be more suitable for RDII prediction during extreme rainfall event, than the regression method.

• Journal of Positioning, Navigation, and Timing
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• v.11 no.4
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• pp.263-268
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• 2022

Precise Point Positioning-Real Time Kinematic (PPP-RTK) is a high accuracy positioning method that combines RTK and PPP to overcome the limitations on service coverage of RTK and convergence time of PPP. PPP-RTK provides correction data in the form of State Space Representation (SSR), unlike RTK, which provides measurement-based Observation Space Representation (OSR). Due to this, PPP-RTK has an advantage that it can transmit less data than RTK. So, recently, several techniques for PPP-RTK have been proposed. However, in order to utilize PPP-RTK techniques, performance analysis of these in a real environment is essential. In this paper, we implement the local network PPP-RTK and analyze the positioning performance according to the distance within 100 km from the reference station in Korea. As results of experiment, the horizontal and vertical 95% errors of local network PPP-RTK were 6.25 cm and 5.86 cm or less, respectively.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.4
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• pp.117-123
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• 2013

The purpose of this research is to suggest the reasonable method of Network RTK surveying in future cadastral re-survey project through the accuracy analysis about Network RTK surveying achievement and the conventional TS-based confirmation surveying. To achieve it, we selected the experiment places and succeeded in achieving the result by Network RTK surveying about total of 307 parcel boundary point. We compared it with the result of confirmation surveying for cadastral, and it was shown that total connection errors of RMSE was ${\pm}0.1028m$ and total 48 places exceeded in the cadastral re-survey allowable error tolerance. The research suggested the practical alternatives in cadastral re-survey project after the comprehensive evaluation of those analysis results. Therefore, the author suggested development and adoptation of integrated electronic plane table surveying method. Moreover, we suggested unifying the first parcel boundary point method into the total station surveying and adopt the Network RTK surveying on the cadastral surveying inspection.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.455-458
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• 2006

The Real Time Kinematic (RTK) technique is the most productive and accurate GPS positioning method today, as it can be determinate position within few centimeters instantly. This method is widely used for applications such as surveying, structure monitoring and machine guidance etc. In order to perform RTK processing for large scale systems (i.e. precise vehicle monitoring with many rovers), many expensive RTK receivers and same number of bidirectional communication units have to be installed to collect observation data communicate with the reference site and monitor its RTK solutions. Moreover, if applications require remote control or apply sensing instruments, we have to install computers at each rover. To limit expense and complexity of system management with a large number of rovers, we have developed server based RTK processing platform to share RTK function for all rovers. The system can be process many GPS stations with a single personal computer. we have also developed a specialized dual frequency GPS receiver unit without on-board RTK processing capability to reduce receiver cost in order to demonstrate the advantage of our server based RTK platform. This paper describes the concept of our server based RTK platform and specialized GPS receiver unit with existing applications in Japan.

• Spatial Information Research
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• v.14 no.2 s.37
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• pp.211-221
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• 2006

GLONASS(Global NAvigation Satellite System) using the satellite information on 19,100km altitude supplies the location information similar method with GPS. Therefore, many researches study in combination GPS and GLONASS. This research compares with deciding coordination of one unit parcel using RTK-GPS and RTK-GPS/CLONASS. Then we examine the possibility of RTK-GPS/GLONASS for determining parcel coordinate.

• Journal of Korean Society for Geospatial Information Science
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• v.22 no.4
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• pp.39-46
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• 2014

Network RTK GNSS positioning technique which has been developed to overcome the limitation of Single reference station RTK is used widely in the field of general surveying, cadastre surveying and engineering surveying due to the high accuracy and efficiency. It is specified Network RTK, Single reference station RTK and Static of GNSS as a surveying method in the regulation of Cadastre Re-survey Surveying. In this study, Network RTK and Static GNSS surveying were accomplished at cadastral re-survey field in Hadong, Gyeongnam and the surveying results were compared. Also, to analyze the performance of site calibration in Network RTK surveying, two types of Network RTK surveying with and without site calibration were accomplished and the results was compared. The research result shows that average positioning error between Network RTK(VRS) without site calibration and Static surveying result is 2.44cm and 1.53cm respectively and average positioning error between Network RTK(VRS) with site calibration and Static surveying result is 0.19cm and 0.82cm respectively at two zone. So, it was proved the effect of calibration in network RTK(VRS) surveying.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.1
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• pp.37-42
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• 2009

The accuracy of RTK GPS is limited by the distance dependent errors from orbit, ionosphere and troposphere, as the distance between the rover and the base station increases in the Real Time Kinematic surveying. To solve this problem, VRS system has installed. This study would estimated the accuracy of cadastral detail surveying, which is used on the VRS RTK instead of Total Station and RTK GPS demand for various equipments and time. As a result of study, the positioning accuracy of the VRS RTK and RTK GPS surveying make no greate difference, as RMSE of VRS RTK surveying is 0.144m and that of RTK GPS surveying is 0.146m and the new method would be more efficient.

• Journal of Korean Society for Geospatial Information Science
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• v.11 no.1 s.24
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• pp.61-69
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• 2003

The study is the open area keeping a few visible satellites and the urban area covered with the high building, an electric pole were chosen for evaluation of accuracy of satellite positioning. First, suggest the validity of RTK-GPS, RTK-GPS/GLONASS and compared the accuracy with that of the classical surveying method. As a result. In urban area, in case of real time kinematic positioning when compare between the method combined by GPS/GLONASS and by GPS alone the result of GPS/GLONASS - combination more excellent. And in open ana positioning combined GPS/GLONASS was more excellent than GPS alone in both real time differential and real time kinematic. So, RTK-GPS, RTK-GPS/GLONASS contribute to the digital mapping of Basic map and the existed map necessary for the building of PBLIS to the computerization of cadastral map in the effectiveness in time and in cost and hereafter the combined GPS/TS is expected to contribute to the development of NGIS, Re-investigation of a land register, the execution drawing on site.

• Journal of Cadastre & Land InformatiX
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• v.45 no.1
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• pp.181-191
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• 2015

In the present study, the 2013 survey Uiwang pointed out how the Resurvey of Cadastre ed projects reviewed relation to the business carried GPS-RTK (Network, Single) and total station surveying (T/S) to analyze and to compare the performance of Time Measurement Accuracy urban areas Resurvey of Cadastre was to present an effective survey methods in the business district. In this study, Uiwang review survey results indicated a comprehensive evaluation of the results, which are concentrated in urban areas, the building of intelligent review of GPS-RTK surveying methods is avoided by the measurement method to establish the first principles method based on total station surveying the GPS-RTK survey to draw conclusions appropriated to take advantage of the assistance and inspection methods.