• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.631-634
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• 2006

Three main important sources for establishing GIS are the orthomap in scale 1:5 000 with Ground Sampling Distance of 0,5m; DEM/DTM data with height error of ${\pm}$1,0m and topographic map in scale 1: 10 000. The new era with Very High Resolution Satellite (VHRS) images as IKONOS, QuickBird, EROS, OrbView and other ones having Ground Sampling Distance (GSD) even lower than 1m has been in potential for producing orthomap in large scale 1:5 000, to update existing maps, to compile general-purpose or thematic maps and for GIS. The accuracy of orthomap generated from VHRS image affects strongly on GIS reliability. Nevertheless, orthomap accuracy taken from VHRS image is at first dependent on chosen sensor geometrical models. This paper presents, at fist, theoretical basic of the Rational Polynomial Coefficient (RPC) model installed in the commercial ImageStation Systems, realized for orthorectifying VHRS images. The RPC model of VHRS image is a replacement camera mode that represents the indirect relation between terrain and its image acquired on the flight orbit. At the end of this paper the practical accuracies of IKONOS and QuickBird image orthorectified by RPC model on Canadian PCI Geomatica System have been presented. They are important indication for practical application of producing digital orthomaps.

• 대한원격탐사학회지
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• 제24권5호
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• pp.437-444
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• 2008

Land-use or land-cover classification of satellite images is one of the important tasks in remote sensing application and many researchers have tried to enhance classification accuracy. Previous studies have shown that the classification technique based on wavelet transform is more effective than traditional techniques based on original pixel values, especially in complicated imagery. Various basis functions such as Haar, daubechies, coiflets and symlets are mainly used in 20 image processing based on wavelet transform. Selecting adequate wavelet is very important because different results could be obtained according to the type of basis function in classification. However, it is not easy to choose the basis function which is effective to improve classification accuracy. In this study, we first computed the wavelet coefficients of satellite image using ten different basis functions, and then classified images. After evaluating classification results, we tried to ascertain which basis function is the most effective for image classification. We also tried to see if the optimum basis function is decided by energy parameter before classifying the image using all basis functions. The energy parameters of wavelet detail bands and overall accuracy are clearly correlated. The decision of optimum basis function using energy parameter in the wavelet based image classification is expected to be helpful for saving time and improving classification accuracy effectively.

• 우주기술과 응용
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• 제1권1호
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• pp.41-48
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• 2021

본 논문에서는 영상의 대각선 정보를 이용하여 원영상의 왜곡이나 성능저하 없이 해상도를 1.4배 증가시킬 수 있는 기술 및 기법에 대해 논하고자 한다. 적용된 방법은 영상을 45도 돌리지 않고도 인접한 4점의 영상정보를 이용하여 카메라의 특성에 맞게 확대 및 재배열을 함으로써, 영상을 실제로 45도 돌리는 것과 동일한 물리적 개념을 적용할 수 있고, 원 영상의 왜곡이나 성능 저하 없이 해상도를 1.4배 증가시킬 수 있는 구체적 실현 방법 및 이에 대한 실증이다.

• 한국지리정보학회지
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• 제12권3호
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• pp.13-20
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• 2009

위성영상을 활용한 변화탐지 기법은 다중시기의 영상을 이용하여 토지의 이용현황에 대한 자연적, 인위적 변화를 효율적으로 탐지할 수 있다. 변화탐지의 경우 위성영상의 보정 방법, 입력데이터 종류, 변화분석 기법에 따라 상이한 결과가 나타난다. 즉, 변화탐지를 위해 동일한 위성과 동일한 영상을 사용하여도 다양한 조건에 따라 다른 결과가 나타나기에 연구 목적에 맞는 적합한 분석기법을 적용해야 한다. 본 연구는 영상의 보정방법에 따른 절대방사보정과 상대방사보정한 위성영상을 기하보정 후 정규식생지수(NDVI)와 주성분분석(PCA)을 하고, 이를 차연산기법(ID:Image Difference)과 비연산기법(IR:Image Rationing)을 이용해 변화탐지 분석을 했다. 그 결과 ID-NDVI의 경우 식생 관련 변화탐지에 매우 우수한 정확도를 나타냈고, ID-PCA는 전 영역에서 90%의 정확도를 보였다. IR-NDVI는 90%의 정확도를 보였으나 전답${\rightarrow}$초지의 경우 70%이하로 나타났고, IR-PCA 역시 전 영역에 대해 우수한 변화탐지능력을 보였다.

• 환경영향평가
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• 제23권2호
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• pp.150-156
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• 2014

The aim of this study is to detection of changed vegetation area of Saemangeum tidal flat with comparison of topography and surface sediments during the dyke construction. Sedimentary facies of four seasons of 2001 from inside Saemangeum tidal flat revealed homogeneous layers in the upper part, however near sea side tidal flat were detecting with carried out rapid sediment deposition during the dyke construction using satellite image spatial analysis. The sedimentation types inside Saemangeum tidal flat were classified with vegetation types, which were well matched with the sedimentation pattern revealed by change in vegetation patterns.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.139-144
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• 2006

Forest fire is due to difficulty in approaching the forest fire at the time of forest fire and quite a long of time required for post-fire investigation, accurate analysis of damages to the forest area caused by forest fire is difficult to obtain. Recently, In attempt to overcome such difficulty, many researches are using satellite images. Nevertheless, it is not easy for everyone to obtain the satellite image data, and additional researches in order to verify accuracy of such data are also required. Therefore, in this study for satellite image to about damages to the forest areas caused by forest fire using tile selected two data of spectral reflectance of the vegetation, gained by using a spectrometer. That is we wished to search about mistake that is apt to happen by one time eyesight observation by analyzing two datas that is used spectral radiometer 3 months and 6 months later and gets.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.518-523
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• 2002

Nowadays the Rational Function Model (RFM), an abstract sensor model, is substituting physical sensor models for highly complicated imaging geometry. But RFM is algorithm to be required many Ground Control Points (GCP). In case of RFM of the third order, At least forty GCP are required far RFM generation. The purpose of this study is to research more efficient algorithm on GCP and accurate algorithm similar to RFM. The Polynomial Camera Model is relatively accurate and requires a little GCP in comparisons of RFM. This paper introduces how to generate Polynomial Camera Model and fundamental algorithms for construction of 3-D topographic data using the Polynomial Camera Model information in the Kompsat stereo pair and describes how to generate the 3-D ground coordinates by manual matching. Finally we tried to extract height information for the whole image area with the stereo matching technique based on the correlation.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.196-200
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• 2004

The purpose of this study is to examine the image­based atmospheric correction models using the data from Landsat Enhanced Thermal Mapper Plus (ETM+) that have quite similar spectral characteristics to the forthcoming Korea Multi-Purpose SATellite (KOMPSAT)-2 Multi-Spectral Camera (MSC), and the in-situ measured surface reflectance data during satellite overflight. The main advantage of this type of correction is that it does not require in-situ measurements during each satellite overflight. While substantial differences are present between Top-Of-the Atmosphere (TOA) reflectance and in-situ measurements, the results showed that Case 1 based on COST model gives most accurate results among three cases. The accuracy of Case 2 is very close to Case 1 and its values are smaller than in-situ data. No notable features appear between some bands in the Case 3 and in-situ data. It is expected from this study that if the current methods are applied to the IKONOS high resolution data, we will be able to develop the suitable atmospheric correction methods for MSC data.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.486-488
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• 2004

The SRI (Super Resolution Imager) uses the CCD (Charge coupled device) detector that is used to convert the light into electronic data. The purpose of the SRI is to obtain data for high resolution images by converting incoming light into digital stream of pixel data. The SRI has a high resolution, so this electronic system needs more fast imaging data processing, detector control and data transmission systems. This report describes the required system specification and manufactured electronic system for satellite.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.449-452
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• 1992

Before performing an adaptive stereo matching using satellite images, classification is needed as a preprocessing step. This paper describes that classification of three land cover types : river, mountain, and agricultural fields. We proposed that classification algorithm using pyramid structure and texture features. Results of applying the proposed algorithm to satellite image improved classification accuracy.