• 한국조경학회지
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• 제27권4호
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• pp.131-136
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• 1999

Aerial videography techniques have been used to inventory conditions associated with grassland, forests, and agricultural crop production. Most recently, aerial videography has been used to verity satellite image classifications as part of the natural ecosystem survey. The objectives of this study were: (1) to use aerial video images of the study area, one part of Taean Seashore National Park, for the accuracy assessment, and (2) to determine the suitability of aerial videography as an accuracy assessment, of the land cover classification with Landsat-TM data. Video images were collected twice, summer and winter seasons, and divided into two kinds of images, wide angle and narrow angle images. Accuracy assessment methods include the calculation of the error matrix, the overall accuracy and kappa coefficient of agreement. This study indicates that aerial videography is an effective tool for accuracy assessment of the satellite image classifications of which features are relatively large and continuous. And it would be possible to overcome the limits of the present natural ecosystem survey method.

• 환경영향평가
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• 제7권2호
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• pp.27-35
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• 1998

In Korea, the initial installation of GIS requires lots of cost, time, and human efforts. If the accuracy of GIS data does not meet the certain standard for use, the system may not work as expected. So, it needs to be investigated for the accuracy of raw data. However, there is little study for the accuracy of raw data in Korea. Therefore, the purpose of this study is to review the data accuracy of raw data - geologic map, 1:5,000 and 1:25,000 scale topographic map, forest stand map, degree of green naturality(DGN) map, and detailed survey data of DGN map-, which are to be used in Environmental Information System(EIS) in Korea. After this study, some errors in data were surveyed and following conclusions were derived. (1) There is no map data, e. g, wildlife habitat map. (2) Some data are misinterpreted depending on the location in the geologic map. (3) Some data are not updated properly after change of topography in the topographic map or the elevation and location is different depending on the scale.. (4) Some data are not edited properly in the forest stand map, e. g. two attributes in one polygon. (5) DGN classification system does not reflect the characteristic of Korean vegetation community. So, it needs to be refined and restructured.

• 한국환경과학회지
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• 제18권10호
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• pp.1079-1088
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• 2009

The statistics of monitoring on soil quality is a report statistics which is made on the basis of Article 15, Environment Strategy Basic Law and Article 5, Soil Environment Conservation Law. This study was conducted according to quality assessment of Korea National Statistical Office. The assessment of quality infrastructure advised that the authority bring up and increase completely responsible officer and secure the budget. The assessment of user satisfaction and reflection of request propose that the statistics is focused on soil background concentration, decrease soil sampling points and extend survey period. The assessment of error management system per processes of detailed preparation suggest change of the statistics objective, a reduction of sampling points and improvement of survey period and soil measurement properties. Accuracy assessment of data proposed cuts of sampling points, accessibility increment and build up of management system linking subordinates and Ministry of Environment. The substantiality assessment of data service demonstrated information environment improvement for users including reference expression and records of statistics table and figure contents.

• 대한공간정보학회지
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• 제14권4호통권38호
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• pp.19-26
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• 2006

본 연구에서는 LiDAR 자료로부터의 지면정보 추출기법들에 대한 정확도를 평가하였다. 특히, 포인트 형태의 벡터자료인 LiDAR 원시자료를 직접 활용하는 기법과 정규격자형식의 DSM 형식으로 변형하여 활용하는 기법의 정확도를 비교하였다. 정규격자형식의 자료를 이용하는 방법으로는 경계추출 및 필터링 기법을 이용하는 방법, 평균필터링에 의하여 생성된 추세면을 이용하는 방법을 적용하였으며, 벡터구조의 원시LiDAR 자료를 직접 활용하는 기법으로써 Local Maxima 및 엔트로피를 이용하는 방법을 적용하였다. 또한, 수작업을 통하여 제작된 DEM 및 수치지도의 축척별 오차허용범위를 이용하여 정확도 평가를 수행하였으며, 경계검출 및 필터링, 추세면, Local Maxima, 엔트로피를 이용한 각 기법의 DEM의 평균 오차는 0.27m, 2.43m, 0.13m, 0.10m로써 엔트로피를 이용한 방법이 가장 높은 정확도를 나타내었다. 또한, 벡터형식의 LiDAR원시자료를 직접 이용하는 방법이 격자형식으로 변환하는 방법에 비하여 상대적으로 높은 정확도를 나타내었다.

• 조명전기설비학회논문지
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• 제27권9호
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• pp.83-89
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• 2013

Power distribution system has been changed from radial system to closed loop or mesh system due to connection of distributed generation growth. Data from distribution equipments which are installed at distribution line is required to be accurate for the performance of DMS(Distribution Management System). This paper analyzes the voltage measurement data from distribution equipment. However, the results of the analysis are confirmed to have some errors in voltage measurement data from distribution equipment. These errors come from aging of voltage sensor in distribution equipment and inaccurate data transfer to FRTU(feeder remote terminal unit) through the controller. The main problem is that the voltage measurement data of distribution equipment can not be assessed after it's first installation at the distribution line. The voltage measurement accuracy assessment system is to assess the voltage measurement data from distribution equipment on hot-line. This study had a field test to verify the performance of system.

• 환경영향평가
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• 제18권1호
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• pp.31-39
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• 2009

A lot of data which are used in environment analysis of air pollution have characteristics that are distributed continuously in space. In this point, the collected data value such as precipitation, temperature, altitude, pollution density, PM10 have spatial aspect. When geostatistical data analysis are needed, acquisition of the value in every point is the best way, however, it is impossible because of the costs and time. Therefore, it is necessary to estimate the unknown values at unsampled locations based on observations. In this study, spatial interpolation method such as local trend surface model, IDW(inverse distance weighted), RBF(radial basis function), Kriging were applied to PM10 annual average concentration of Seoul in 2005 and the accuracy was evaluated. For evaluation of interpolation accuracy, range of estimated value, RMSE, average error were analyzed with observation data. The Kriging and RBF methods had the higher accuracy than others.

• Journal of Electrical Engineering and Technology
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• 제10권3호
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• pp.1328-1334
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• 2015

A new system for evaluating the voltage management errors of distribution equipment is presented in this paper. The main concept of the new system is to use real distribution live-line voltage to evaluate and correct the voltage measurement data from distribution equipment. This new approach is suitable for a new Distribution Management System (DMS) which has been developed for a distribution power system due to the connection of distributed generation growth. The data from distribution equipment that is installed at distribution lines must be accurate for the performance of the DMS. The proposed system is expected to provide a solution for voltage measurement accuracy assessment for the reliable and efficient operation of the DMS. An experimental study on actual distribution equipment verifies that this voltage measurement accuracy assessment system can assess and calibrate the voltage measurement data from distribution equipment installed at the distribution line.

• 한국전자파학회논문지
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• 제26권9호
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• pp.828-836
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• 2015

본 논문은 위상배열 레이더를 사용하여 실제표적을 추적하였을 때 추적 정확도를 평가하기 위한 알고리듬 연구이다. 실표적에 대한 추적 정확도를 평가하기 위해서는 실표적 위치에 대한 정보가 있어야 하지만, 시험비용 및 시험시간의 증대로 인해 위상배열 레이더에서 획득된 데이터만을 사용하여 실표적의 정확도를 평가하는 알고리듬을 제시한다. 이러한 평가 알고리듬은 위상배열 레이더에서 사용된 ${\alpha}-{\beta}$ 추적필터의 잔차로부터 추적 정확도의 지표인 거리오차와 각도 오차의 표준편차를 도출한 결과이며, 통계적 방법으로 sample variance 개념을 사용하게 된다.

• 환경영향평가
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• 제18권6호
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• pp.387-392
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• 2009

As Our society's environmental awareness and concern the significant increases, the importance of the legal system for environmental conservation such as the Prior Environmental Review System, Environmental Impact Assessment is growing increasingly. but, still critical issues are present such as reliability. Though there could be various causes such as the system or procedures etc. Above all, basically the environmental data problem is the critical cause. Therefore, this study was trying to improve the environmental data accuracy using the high-resolution color aerial photography, LiDAR data and Object Oriented Classification method. And in this study, classification based on coverage percentage of a particular species was attempted through the multi-resolution segmentation and multi-level classification method. The classification result was verified by comparison with 11 points local survey data. All 11 points were classified correctly. And even though the exact coverage percentage of the particular species did not be measured, It was confirmed that the species was occupied similar portion. It is important that the environmental data which can be used for the conservation value assessment could be acquired.

• 환경영향평가
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• 제20권5호
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• pp.601-613
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• 2011

This study is focused on a climate data integrity to improve water quality assessment due to the social development projects. The study is in an attempt to calculate both extreme ranges of weather data measurements and partly provide means to assess qualification of data which fall within the extremes at the 23 meteorological weather stations. Generally speaking, maximum temperature, minimum temperature, relative humidity, dew point temperature are in the range of reasonable accuracy. However, there found some outliers of the brightness sunshine hours in Cheonan station. Also some years in Gwangju, Seoul, Wonju, Busan, and Jeju never reach to their upper limit and perhaps the calibration of the equipment is doubtful. The users need to take cautions in using the brightness sunshine hour data in preparation of water resources planning and management by estimating evapotranspiration and river discharge, and/or growth rate of the algae (phytoplankton).