• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.22 no.2
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• pp.137-143
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• 2004

The electronic distance measurement(EDM) instrument, introduced first in the 1950s since those early days has, undergone continual refinement. Rapid advances established in related technologies have made it lighter, smaller and more precise equipment. Understanding for the principle, the standardized observation technique and the precision of EDM instrument is mostly important to improve the quality and the reliability of by-product in the field of engineering and industrial surveying. Periodical and accurate calibration is necessary to maintenance the precision of EDM instrument. This paper describes the calculated example of zero error and scale error as a correction of EDM by applying the least square method to baseline observations in test area. Also here we deal with the testing criteria for precision instrument testing according to different types of EDM instruments.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.531-534
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• 2003

본 연구는 지적도면전산화사업으로 수치화된 데이터를 PBLIS에 이용하여 지적업무를 수행하고 있으며, 이 데이터를 토탈측량시스템(Pen컴퓨터)에 활용함으로서 도해지적에서 발생되는 제도오차, 축척오차 및 지적도면의 신축오차 등의 기술적인 오차와 측량을 할 때마다 측량사에 따른 개인오차를 제거하여 정확도를 향상시키고, 인접 필지의 반복적인 실형 측량을 배제함으로서 현장에서 소요되는 시간이 절약하게 될 것이다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.9 no.1
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• pp.75-82
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• 1991

The objective of this paper is to investigate the optimal Robust estimation and scale estimator that could be used to treat the gross errors in a self calibrating bundle adjustment. In order to test the variability in performance of the different weighting schemes in accurately detecting gross error, five robust estimation methods and three types of scale estimators were used. And also, two difference control point patterns(high density control, sparse density control) and three types of gross errors(4$\sigma o$, 20$\sigma o$, 50$\sigma o$) were used for comparison analysis. As a result, Anscombe's robust estimation produced the best results in accuracy among the robust estimation methods considered. when considering the scale estimator about control point patterns, It can be seen that Type II scale estimator provided the best accuracy in high density control pattern. On the other hand, In the case of sparse density control pattern, Type III scale estimator showed the best results in accuracy. Therefore it is expected to apply to robustified bundle adjustment using the optimal scale estimator which can be used for eliminating the gross error in precise structure analysis.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2001.10a
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• pp.17-44
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• 2001

지적도는 모든 지도중 가장 큰 대축척 지도이며 토지에 대하여 필지별로 지번, 위치 및 경계 등 소유권의 범위를 등록하는 것으로서 국민의 기본권리인 토지에 대한 소유권과 그 이용을 보장할 수 있는 가장 기본적인 특성을 가지고 있다. 도형자료인 현재의 지적도는 1910년 토지조사사업에 의하여 실제 토지필지를 1/1,200로 축소하여 도면에 등록한 도해지적으로 제도오차, 축척오차, 신축오차, 도곽접합 등의 기술적인 오차와 측량을 할 때마다 각기 측량사에 따라 개인오차의 누적으로 성과결정에 있어서 차질을 가져다주고 있다. 따라서 이러한 문제를 해결하기 위하여는 지적재조사사업이 가장 바람직하지만 복잡한 과정을 거쳐야 함으로 그 이전에라도 축척변경사업을 통하여 새로운 지적체계로서 토지이용상태에 따라 토지의 경계를 수치좌표로 등록하는 수치지적체계로 전환하여 지적측량의 정확도와 정밀도를 높여 지적불부합지에 대한 민원을 해소함으로써 재산적 가치를 증대할 뿐만 아니라 국민의 소유권 보호 및 양질의 서비스 개선에 그 목적이 있다. 본 연구에서는 해당지역의 지적도를 독취, 정도곽으로 보정하여 일필지를 공부상면적의 공차범위 이내로 조정한 후 현형도와 지적도를 조정(Orientation)하여 좌표를 저장하였다. 일필지 좌표결정 방법에는 CAD기능을 이용하여 컴퓨터의 모니터에서 지적도를 이동 및 회전함으로써 위치를 결정하는 방식, 모니터상에서 국부적으로 위치를 결정하는 방식 및 디지타이져상에서 결정하여 모니터상에서 조정하는 방식있다. 현실적으로 국부적인 방법이 합리적이라고 생각되어 모니터상에서 조정(Orientation)하여 국부적으로 좌표 위치를 결정하는 방법으로 연구하고 성과를 비교, 검토하였으며, 그 결과 다음과 같은 결론을 얻었다. 1. 지적도면은 토지조사사업 한지를 배접한 켄트지를 사용함으로써 종이의 신축으로 인하여 정도곽으로 보정을 하면 독취면적은 대부분 공부상면적보다 늘어났다. 2. 좌표의 이동량이 일률적이지 못하므로 기초점에 대한 문제라고 생각되며, 따라서 도해지적을 수치지적으로 전환함에 있어서 가장 우선되어야 할 사항이 기초점 정비라 하겠다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.05a
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• pp.105-109
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• 2003

A new scaling method for the prediction of gas turbine components characteristics using experimental data of gas turbine test unit has been proposed. In order to minimize the analyzed performance error in the this study, firstly component maps were constructed by real experimental performance data at some operating conditions and a polynomial obtained from scaling factors at given conditions, and then the simulated performance using the identified maps was compared with the performance result using the currently used traditional scaling method. In comparison, the performance analysis result by the currently used traditional scaling method was met well agreed with the real engine performance at most off-design points except for the design point. However the performance analysis result using the newly proposed scaling method had good agreement with the experimental results within maximum 5％ error.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.3
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• pp.209-214
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• 2003

The tasks in the cadastral field are being carried out by the aid of Parcel Based Land Information System which is equipped with both graphical and textual information acquired by the Cadastral Map Computerization Project. This have the purpose to present efficient surveying method as analyzing the accuracy about the field map We can also avoiding the drafting error caused by graphical cadastral and technical error including scale and contraction error as inverting an existing surveying system to the computer surveying system with this data.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.7
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• pp.36-43
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• 2002

A new scaling method for the prediction of gas turbine components characteristics using experimental data or partially given data from engine manufacturers has been proposed. In order to minimize the analyzed performance error in the this study, firstly component maps were constructed by identifying performance data given by engine manufacturers at some operating conditions, then the simulated performance using the identified maps was compared with the performance result using the currently used traditional scaling method. In comparison, the performance result by the currently used traditional scaling method was well agreed with the real engine performance at on-design point but it had maximum 12% error at off-design points within the flight envelope of a study turboprop engine. However because the analysed performance by the newly proposed scaling method had maximum 6% reasonable error even within all flight envelope.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.529-534
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• 2004

고해상도 위성영상을 이용하여 수치지도를 제작함에 있어 가장 큰 문제점은 레스터 자료인 위성영상에서 경계검출을 통해 벡터자료의 형태로 제작하는 어려움이 있다. 본 연구에서는 경계검출을 통하여 위성영상에서 지형의 경계를 검출해내고, 이를 스크린 디지 타이징 기법을 적용하여 벡터라이징 한 후 나타난 결과를 국토지리정보원의 수치지도와 비교하여 정확도를 비교ㆍ평가하였다. 대상 범위는 대전광역시 유성구 가정동 일부지역을 IKONOS로 촬영된 공간해상도 1m의 위성영상을 사용하였다. 위성영상의 전처리는 기하보정과 정사보정을 거친 후 영상강조를 하였고, 여러 가지의 필터링을 적용하여 경계검출을 수행하였다. 경계검출 방법 중에 하나인 Sobel 연산자를 적용한 후 축척 1:5,000 수치지도와의 중첩을 통하여 표준편차(Root Mean Square Error : RMSE)를 산출하여 비교ㆍ분석하였다. 그리고 스크린 디지타이징 기법을 적용하여 추출한 벡터자료를 건물, 도로 및 임야로 분류하여 수치지도와 중첩하여 정확도를 분석하였다. 그 결과 건물과 도로의 경우에는 공공측량 작업규정에서 정하고 있는 축척 1:5,000의 평면위치 허용오차 기준을 만족하고 있지만, 임야의 경우는 축척 1:10,000 이상의 허용오차기준에 만족되고 있음을 알 수 있었다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.6
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• pp.677-685
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• 2011

In order to enhance public transportation and to maintain information credibility, improvement of accuracy regarding route and positional information of public transport is very significant. There have been a variety of methods using GPS to measure accuracy of location-based services. However, the researches of evaluation regarding kinematic position of linear objects measured by vehicle/kinematic GPS are still insufficient. That's why our paper aims to suggest method of evaluation accuracy on a real-time bus route surveyed by GPS by SBM(Single Buffering Method). To make it come true, we compared the findings on the static and dynamic positioning by using PP(Point Positioning), DGPS and GPS/INS integrated systems and analyzed the accuracy and error effects among them, focusing on Anyang city. Consequently, we can find out that in case of P.P. comparing positioning accuracy between RTK DGPS and GPS/INS, both of them have survey result within a margin of error of 5m. More importantly, we can evaluate positional accuracy of each GPS system based on the work provision of a public survey such as error for P.P.(14.5m, 18.1m), DGPS(16.9m, 18.5m), and GPS/INS(18.4m, 18.5m). We are expecting that proposed method in our paper can be utilized in a wide range of categories such as feasibility testing of GPS field survey and high accuracy of positioning for Bus Information System.

• Journal of Korean Society for Geospatial Information Science
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• v.6 no.2 s.12
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• pp.119-132
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• 1998

Much information on the terrain and the space has been depicted to maps of various form according to the map scale and the application. In Korea the base map system was made by only one projection method(Transvers Mercator projection). This is the reason to study this paper, because I think singular map projection method can't satisfy the various map scales and application. In this paper Meridian Are Length, Parallel Are Length of ellipsoid and the area of ellipsoidal surface-the length, the width and area of the map scale 1/5,000, 1/25,000, 1/5,000, 1/1,000, will be calculated and transformed to the plane length and area by Transvers Mercartor projection and Polyhedrical projection. The projection distortion which came into existence on this occasion was compared and analyzed by this Paper. And Properties on TM and Polyhedrical projection were understood. Lastly this paper intended to present suitable map projections according to the map scales and the purpose of use.