• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.97-102
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• 2004

현재 4차원 정밀측정이 가능한 GPS는 데이터 처리와 사용기기 면에서 많은 발전을 이루고 있으며, 정밀한 데이터 결과를 제공하고 있다. 처리 방식에 따른 기선거리별 한계치에 대한 재검증을 실시하고자 하였으며, 측지용 GPS 수신기를 이용한 기선측정에 있어, L$_1$주파수 수신 GPS 시스템의 유효측정거리에 대하여 논하였다. 또한 일반적인 기선처리방식 이외의 다양한 처리기법들을 적용하여 각 단ㆍ중ㆍ장기선에 대해 가장 알맞은 처리방식을 도출하려고 하였으며 결과를 도출하는 과정에서 GPS 상대거리 관측데이터에 대해 양호한 데이터를 선별할 수 있는 기준 안을 마련하고자 하였다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.45-49
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• 2004

The Navstar Global Positioning System(GPS) is an advanced navigation satelite system for determination of position, velocity and time. It can provide three-dimensional positioning on a global basis, independent of weather, 24 hours per day. Test results show that the carrier phase and pseudorange corrections are suitable for a kinematic GPS system. Using these corrections are more effective than using raw GPS data, since fewer bits are required for transmission Additionally, the number of computation required at the rover is reduced when corrections, rather than raw measurement are transmitted

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.433-441
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• 2003

최근 SA(Selective Availability)의 해제에 따른 GPS의 활용이 증대되면서 차량운행에 있어서도 저가 GPS 수신기의 활용이 활발하게 이루어지고 있으며, 일반 차량 운행자를 위한 상용화가 급속도로 이루어지고 있다. 하지만 저가 GPS수신기를 통한 실시간 위치정보의 제공은 실질적으로 상당한 오차를 포함하고 있다. 이는 저가 수신기가 가지고 있는 문제라 할 수 있다. 이에 본 연구에서는 저가 수신기와 정밀 측위용 이주파 수신기를 이용하여 측지분야에서 검증된 GPS측량방법을 통해 오차를 비교ㆍ분석하고 저가 수신기의 정확도 향상을 위한 방법을 제시하고자 하였다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.423-427
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• 2010

현재 GPS/INS 운영 방법은 일정한 범위 내에 GPS 지상기준국을 설치하도록 되어있다. 그러나 촬영지역이 넓을 경우나 작업의 우선순위 등에 따라 지상기준국의 운영이 곤란한 상황이 발생할 수 있으며, 작업자의 실수, 수신기의 오류 등으로 지상기준국을 항상 안정적으로 운영하기 어렵다. 이에 본 연구에서는 국토지리정보원의 GPS 상시관측소를 활용하여 항공레이저측량 원시자료를 구축하고, 지상 기준국을 사용한 결과와의 비교를 통해 기준국이 항공레이저측량 결과에 미치는 영향을 분석하고자하였다.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.1 s.19
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• pp.51-57
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• 2002

GPS proved to very practical in the application of geodesy and surveying such Civil Engineering, control point surveying and the deformation surveying o( structure, but the accuracy of static GPS positioning is degraded at the sites which the visible satellites of GPS are less than 4, i.e. the urban area covered with the high building and the industrial zone. Thus, the combined GPS/GLONASS system was introduced to acquire the high accuracy of static positioning by a few satellites. So the combined GPS/GLONASS system show the good results at the sites which the accuracy of positioning is degraded due to few satellites, the cutoff of signal, and multipath in the urban area.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.195-206
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• 1997

By this time, in order to measure baseline in a few minutes, we must have used expensive dual frequency receiver. Recently, low-priced single frequency receiver have taken place of dual frequency receiver at short base-line by advancement in software development, improvements in geodetic survey receiver system. In this study, according to the observation time and measurement interval, we analyzed differences of each components of baseline by field experiment and we propose the criterion for the minor control point surveying by single frequency GPS receiver.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2009.04a
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• pp.119-123
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• 2009

In the areas of civil engineering or cadastral surveying, multi-orientation process such as setting out boundary mark is regarded as one of the important tasks, measuring land feature and indicating acquired data to the grounds. In case of using dual frequency receiver and TS(total station), there are much advantages in setting out surveying results in the field. However, it costs very expensive and the equipments for enhancing correctness are very complex. In this study, technical factor was reviewed in which single frequence receiver and TS, comparatively cheap and easy to establish a system, was connected into TS(Total Station) in order to make easy to orientation and setting out. As a result of this study, it was possible to support GPS and TS surveying and set out it by short distance wireless communication method using single frequency GPS receiver. And by developing the system, it also could lessen the time of setting out in large areas and difficulty of the surveyors in the field.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.1
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• pp.19-26
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• 2001

The Organizations working with technological projects will be more and more common to connect consultants. Those who shall carry out the pre-analysis of the projects ought to have a professional knowledge to the area about economical methods with information technology and changed technology of surveying and mapping. New surveying and mapping methods, such as TotalStation, GPS, orthophoto, digital map, and satellite remote sensing, have totally changed the old concept of surveying. Also the technology for the new mapping has greatly changed from analog to analytical to digital during the past 50 years. Now, the proper choice of surveying and mapping methods becomes a decision on cost and efficiency rather than the use of a particular technology. As an example, GPS equipment dose cost considerably more than traditional surveying equipment, but the advantages it provides make it very cost-effective. In this study, the cost and benefit factors of the surveying and mapping projects are evaluated independently and benefit/cost ratio(B/C ratio) is used in benefit-cost evaluation of the different surveying methods. The benefit-cost model of surveying and mapping methods will produce economical result in the whole projects.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.4
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• pp.403-410
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• 1999

Mark point(Donghaksan) of Korean geodetic datum in Suwon could not be intervisible because of the development of the surroundings, so we were in a situation that we should establish new mark point and decide azimuth of the new mark point. Getting out of the intervisibility between control stations, refraction error and effect of illumination in urban area, our research team decided new azimuth of Suwon Geodetic Datum by GPS surveying for accuracy and economical efficiency. First we corrected and supplemented the specification on the decision of azimuth in accordance with our situation based on the study of foreign studies by using GPS, and we determined and analyzed the accuracy of the new azimuth through organizing and observing the GPS network.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.421-424
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• 2003