• 대한원격탐사학회지
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• 제17권1호
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• pp.33-44
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• 2001

본 논문은 지상기준접의 취득이 어려운 비접근 지역에 대한 위성영상에서 지형정보를 획득하기 위한 방법을 제시하였다. 먼저, 공선조건식을 기반으로 10개의 위성센서모델을 개발하고, 개발된 센서모델의 거동을 부석하기 위하여 Space Resection 및 Space Intersection을 통해 각각의 센서모델에 대한 적합성을 실험하였다. 이를 바탕으로 비접근 지역에 대한 지형정보를 취득하기 위하여 영상을 재구성하거나 Pseudo영상을 제작하고, 이에 대한 센서모델의 거동 및 정확도를 분석.제시하였다. 공선조건식을 이용한 Pushbroom 위성영상의 센서모델은 투영중심의 위치와 회전요소에 대한 6개의 외부표정요소를 영상의 행에 대한 1차, 2차 함수 또는 3차 함수로 구성하였으며, 또한 외부표정요소의 위치요소와 상관도가 높은 회전요소($\omega$, $\Phi$)를 고정된 값으로 사용하는 센서모델을 개발하였다. 비접근 지역을 위한 영상의 재구성은 동일 패스의 지상기준접이 있는 영상과 비접근 지역의 영상을 연결시켜 하나의 영상으로 재구성하거나, 지상기준점이 있는 영상과 비접근 지역의 영상으로부터 Pseudo영상을 임의로 제작하여 패스내에서 중복영역을 갖도록 구성하였다. 본 연구에서 이용한 인공위성 데이터는 서로 다른 패스에서 동일한 지역을 촬영한 SPOT 영상이며, 각각의 패스에서 두장의 연속된 영상을 이용하였다. 개발된 10개의 센서모델과 5가지의 영상 재구성 방법에 따라 비접근 지역에서의 정확도는 다르게 나타났으며, 그 중 투영중심의 위치 및 회전요소 k를 1차 함수로 표현하고 회전요소 $\omega$, $\Phi$를 고정시킨 센서모델과 Pseudo영상을 이용한 방법이 비접근 지역 30km, 60km지점의 검사점에서 각각 최대오차 30m, 60m의 결과를 보였다. 얻어진 극한하중 보다 적은 경향을 나타냈다.aeuntang were higher than the recommended value per meal. Vitamin A, vitamin C, vitamin B$_1$, vitamin B, niacin, calcium, phosphorus and iron were rich in chwotang and minmulgokimaeuntag. Onhuk contains plenty of vitamin C, vitamin B$_1$, vitamin B$_2$and the contents of vitamin A, vitamin B$_1$, and niacin in baekhapapchuk were over the recommended values per meal. The foods contained large percentage of aspartic acid and glutamic acid, and major essential amino acids appeared to be leucine and lysine. On the other hand, major fatty acids were oleic acid, linoleic acid and plamitic acid. Among them the content of oleic acid was the highest in chuotang, ochuk and baekhapchuk, whereas linoleic acid and palmitic acid were the most rich fatty acids in baekhapchuk and dasulgitang respectively.한 있을 것으로 생각된다. 그리고 본 조사는 5월부터 7월중에 실시하였는데, 한국의 경우 계절에 따라 섭취 식품의 종류가 다

• 한국측량학회지
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• 제31권6_2호
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• pp.593-599
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• 2013

China's Mapping Satellite-1, developed by the China Aerospace Science and Technology Corporation (CASC), was launched in three years ago. The data from Mapping Satellite-1 are able to use for efficient surveying and geometric mapping application field. In this paper, we fuse the panchromatic and multispectral images of Changchun area, which are obtained from the Mapping Satellite-1, the one that is the Chinese first transmission-type three-dimensional mapping satellite. The four traditional image fusion methods, which are HPF, Mod.IHS, Panshar and wavelet transform, were used to approach for effectively fusing Mapping Satellite-1 remote sensing data. Subsequently we assess the results with some commonly used methods, which are known a subjective qualitative evaluation and quantitative statistical analysis approach. Consequently, we found that the wavelet transform remote sensing image fusion is the optimal in the degree of distortion, the ability of performance of details and image information availability among four methods. To further understand the optimal methods to fuse Mapping Satellite-1 images, an additional study is necessary.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.780-785
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• 2002

As the KOMPSAT-1 satellite can roll tilt up to $\pm$45$^{\circ}$, we have analyzed some EOC images taken at different tilt angles fur this study. The required ground coordinates for bundle adjustment and geometric accuracy, are read from the digital map produced by the National Geography Institution, at a scale of 1:5, 000. These are the steps taken for the tilting angle of KOMPSAT-1 satellite to be present in the evaluation of the accuracy of the geometric of each different stereo image data: Firstly, as the tilting angle is different in each image, the satellite dynamic characteristic must be determined by the sensor modeling. Then the best sensor modeling equation is determined. The result of this research, the difference between the RMSE values of individual stereo images is due more the quality of image and ground coordinates than to the tilt angle. The bundle adjustment using three KOMPSAT-1 stereo pairs, first degree of polynomials for modeling the satellite position were sufficient.

• 대한원격탐사학회지
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• 제18권6호
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• pp.327-336
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• 2002

다양한 분야에서 고해상도 위성영상의 활용도가 높아짐에 따라 많은 고해상도 인공위성이 발사되고 있으며 발사예정에 있다. 본 논문은 DEM과 항공사진영상을 이용하여 임의의 궤도정보와 자세정보를 가지는 인공위성에 대하여 모의위성영상을 제작할 수 있는 두 가지 방법을 제안하였다. 제작된 모의위성영상의 센서모델에서 자세는 변화가 없는 것으로 가정하였고, 투영중심의 위치는 위성의 진행방향에 따라 변화하는 모델을 사용하였다. 또한 자세와 위치에 변화를 준 모의위성영상을 제작하여 입체시 가능성을 실험하였으며, 제작된 모의위성영상의 정확도를 검증하기 위해 공간전방 교회를 이용하여 검증하였다.

• 대한원격탐사학회지
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• 제15권4호
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• pp.339-348
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• 1999

To extract value-added products which are important in scientific area and practical life, e.g. digital elevation models, ortho-rectified images and geometric corrected images, Satellite Technology Research Center at Korea Advanced Institute of Science and Technology has developed a satellite image processing software called "Valadd-Pro". In this paper, "Valadd-Pro" software is briefly introduced and its main components such as precise geometric correction, ortho-rectification and digital elevation model extraction component are described. The performance of "Valadd-Pro" software was assessed on 10m resolution 6000 $\times$ 6000 SPOT panchromatic images (60km $\times$ 60km) using ground control points from GPS measurements. The height accuracy was measured by comparing our results with 100m resolution $DTEDs^{1)}$ produced by USGS and 60m resolution DEMs generated from digitized contours produced by National Geography Institute. Also, to show the superior performance of "Valadd-Pro" software, we compared the performance with that of commonly used PCI$\circledR$ commercial software. Based on the results, the geometric correction of "Valadd-Pro" software needs fewer ground control points than that of PCI$\circledR$ software and the ortho-rectification of "Valadd-Pro" software shows similar performance to that of PCI$\circledR$ software. In the digital elevation model extraction, "Valadd-Pro" software is two times more accurate and four times faster than PCI$\circledR$ software.ccurate and four times faster than PCI$\circledR$ software.

• 대한원격탐사학회지
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• 제34권6_4호
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• pp.1469-1478
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• 2018

지진과 화산은 막대한 인적 물적 피해를 발생시킬 수 있는 재해로서 광범위하게 영향을 미치기 때문에 이에 대한 효과적인 모니터링이 요구된다. 위성 자료가 많아지면서 효율적 지진 화산 모니터링을 위한 위성영상 기반의 연구가 많이 발전하고 있다. 위성영상의 종류는 크게 광학, 열적외선, 영상레이더로 구분할 수 있으며 각 위성영상 종류에 따라 서로 다른 특성을 가지고 있다. 여기서는 우선 각 종류별 장점과 단점을 정리하였다. 또한 국내 연구자들에 의해 수행된 위성 영상을 활용한 지진과 화산 관련 연구를 살펴보고 이를 토대로 지진과 화산 재해 대응을 위한 위성 영상의 종류별 활용 방안을 제시하고자 한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2000년도 춘계 학술대회 논문집 통권 3호 Proceedings of the 2000 KSRS Spring Meeting
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• pp.49-54
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• 2000

Conventional methods for measuring winds provide wind velocity observations over limited area and time period. The use of satellite imagery for measuring wind velocity overcomes some of these limitations by providing wide area and near condinuous coverage. And its accurate depiction is essential for operational weather forecasting and for initialization of NWP models. GMS-5 provides full disk images at hourly intervals. At four times each day - 0500, 1100, 1700, 2300 hours UTC-a series of three images is received, separated by thirty minutes, centered at the four times. The current wind system generates winds from sets of 3 infrared(IR) images, separated by an hour, four times a day. It also produces visible(VIS) and water vapor(WV) image-based winds from half-hourly imagery four times a day. The derivation of wind from satellite imagery involves the identification of suitable cloud targets. tracking the targets on sequential images, associating a pressure height with the derived wind vector, and quality control. The aim of this research is to incorporate imagery from other available spectral channels and examine the error characteristics of winds derived from these images.

• 한국멀티미디어학회논문지
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• 제25권7호
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• pp.895-902
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• 2022

Building segmentation using satellite imagery such as EO (Electro-Optical) and SAR (Synthetic-Aperture Radar) images are widely used due to their various uses. EO images have the advantage of having color information, and they are noise-free. In contrast, SAR images can identify the physical characteristics and geometrical information that the EO image cannot capture. This paper proposes a learning framework for efficient building segmentation that consists of a teacher-student-based privileged knowledge distillation and deformable convolution block. The teacher network utilizes EO and SAR images simultaneously to produce richer features and provide them to the student network, while the student network only uses EO images. To do this, we present objective functions that consist of Kullback-Leibler divergence loss and knowledge distillation loss. Furthermore, we introduce deformable convolution to avoid pixel-level noise and efficiently capture hard samples such as small and thin buildings at the global level. Experimental result shows that our method outperforms other methods and efficiently captures complex samples such as a small or narrow building. Moreover, Since our method can be applied to various methods.

• 대한원격탐사학회지
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• 제34권5호
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• pp.777-786
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• 2018

GF(Guided Filtering)는 영상에 존재하는 에지 정보를 보존하면서 잡음을 효과적으로 제거하기 위한 대표적인 영상처리 기법이다. 본 연구에서는 GF를 이용하여 다시기 KOMPSAT-3 위성영상에 대한 무감독 변화 탐지 기법을 수행하고, 이에 대한 성능을 평가하고자 하였다. GF를 변화탐지에 활용하기 위하여, GF를 기반으로 교차융합영상을 생성하였으며, 생성된 교차융합영상에 CVA(Change Vector Analysis) 기법을 적용하여 변화 지역을 추정하고자 하였다. KOMPSAT-3 위성영상을 이용한 실험결과, 본 연구에서 제안한 기법이 기존의 영상융합 기법을 기반으로 하는 CVA 결과들과 비교하여 효과적으로 변화지역을 탐지하는 데에 활용할 수 있음을 확인하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.301-304
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• 2008

Since longer wavelength microwave radiation can penetrate clouds, satellite passive microwave sensors can observe sea ice of the entire polar region on a daily basis. Thus, it is becoming popular to derive sea ice motion vectors from a pair of satellite passive microwave sensor images observed at one or few day interval. Usually, the accuracies of derived vectors are validated by comparing with the position data of drifting buoys. However, the number of buoys for validation is always quite limited compared to a large number of vectors derived from satellite images. In this study, the sea ice motion vectors automatically derived from pairs of AMSR-E 89GHz images (IFOV = 3.5 ${\times}$ 5.9km) by an image-to-image cross correlation were validated by comparing with sea ice motion vectors manually derived from pairs of cloudless MODIS images (IFOV=250 ${\times}$ 250m). Since AMSR-E and MODIS are both on the same Aqua satellite of NASA, the observation time of both sensors are the same. The relative errors of AMSR-E vectors against MODIS vectors were calculated. The accuracy validation has been conducted for 5 scenes. If we accept relative error of less than 30% as correct vectors, 75% to 92% of AMSR-E vectors derived from one scene were correct. On the other hand, the percentage of correct sea ice vectors derived from a pair of SSM/I 85GHz images (IFOV = 15 ${\times}$ 13km) observed nearly simultaneously with one of the AMSR-E images was 46%. The difference of the accuracy between AMSR-E and SSM/I is reflecting the difference of IFOV. The accuracies of H and V polarization were different from scene to scene, which may reflect the difference of sea ice distributions and their snow cover of each scene.