• 대한원격탐사학회지
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• 제25권1호
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• pp.85-94
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• 2009

본 논문은 중적외선 밴드가 없는 고해상도 QuickBird 화상을 이용하여 옥계 산불피해지의 삼림교란 지도화에 관한 연구이다. Landsat ETM+ ${\Delta}NBR$에 기초한 QuickBird NBR을 통해 산불피해등급도 보다 발전된 산불후 삼림교란도를 작성하였다. 무엇보다 QuickBird 수분지수와 Landsat ETM+ 7(중적외선)밴드 간의 상관계수에 QuickBird 수분지수를 곱한 치환수치로 생성되는 MIR모의밴드를 통해 산불피해 등급도와 산불후 삼림교란도가 제작된다. QuickBird NBR기반의 산불후 삼림교란도는 Landsat ETM+ ${\Delta}NBR$기반의 산불피해등급도와의 비교 정확도 평가에서 본질적 확실의 높은 일치성(KHAT값=0.7886)을 갖고 있어, 산불피해지의 자연복원 나아가 삼림벌채로 야기된 삼림교란에 유용하게 사용될 것이다.

• 대한원격탐사학회지
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• 제30권6호
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• pp.709-717
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• 2014

본 연구는 사영변환행렬을 적용한 경우 건물벽면 영상 간 코너점의 대응정도를 분석하는 것을 목표로 한다. 부가적으로 코너점을 찾기 위한 적절한 연산자를 실험을 통하여 결정하였다. 건물형상에 대한 모델링은 항공사진, 항공라이다영상, 지상사진, 지상라이다영상 등 다양한 자료를 이용하여 많은 기법들이 연구되어 왔다. 본 연구에서는 영상 간 정합을 위하여 필요한 코너점 검출방법으로 Harris 연산자와 FAST 연산자의 성능을 비교하였다. 비교결과 Harris 연산자가 건물벽면에서 코너점 추출에 우수하다는 결론을 내렸다. Harris 연산자로 코너점 검출 후, 사영변환행렬을 통하여 코너점 들의 대응정도를 비교한 결과, 대부분의 경우 최소거리에 실제 대응점들이 위치해 있음을 알 수 있었다. 사영변환행렬의 성능을 기준점 수와 분포를 고려하여 대응정도에 미치는 영향을 분석한 결과 기준점이 많고 골고루 분포한 경우에 더욱 정확한 대응 관계를 제공하는 것으로 나타났다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1140-1142
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• 2003

Imagery and gridded data can be used as the sources of extracting important information and data layers in utilizing GIS. The existing metadata standard to distribute and to utilize the geographic information are mainly concentrated at the vector data and do not provide metadata components for imagery and gridded data. In this study, metadata components for imagery and gridded data have been investigated. Firstly, existing international metadata standards such as ISO and domestic standards of TTA have been analyzed. Based on th results, the draft metadata for imagery and gridded data have been proposed as the extensions of domestic metadata standard distribution. The draft metadata could contribute to build the basic standards to access and utilize proper imagery and gridded data fit to various application field, and this will be fundamental bases for activating GIS in public and private sectors.

• 한국지리정보학회지
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• 제23권2호
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• pp.70-82
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• 2020

최근 도시홍수에 의해 많은 피해가 발생하고 있으며, 단시간에 국지적으로 발생하는 집중호우가 1차 원인으로 꼽히고 있다. 도시홍수의 피해는 도시지역 내 물수지의 변화로 규명하고 있으며, 이를 간접적으로 파악하기 위해 일강수량 자료와 다중시기 Sentinel-2 위성영상을 활용해 집중호우 전후의 토지피복별 원격탐사지수 변화를 분석하였다. 일강수량 자료를 바탕으로 호우주의보 및 경보의 사례를 선정하였고, 해당 기간의 Sentinel-2 위성영상을 취득해 이를 기상청 서울관측소 기준 반경 1,000m 범위의 정규식생지수(NDVI), 정규수분지수(NDWI) 및 정규습윤지수(NDMI) 영상을 토지피복별로 제작하여 통계적 변화를 비교하였다. 각 영상을 구성하고 있는 픽셀의 최댓값, 최솟값, 평균 및 그 증감을 분석한 결과, 집중호우 전후 도시지역 원격탐사지수에 유의미한 변화가 발생한 것으로 보기는 힘들다고 판단하였다.

• 항공우주정책ㆍ법학회지
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• 제4권
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• pp.177-206
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• 1992

Commercial remote-sensing is one of the applied fields of space activities which, like telecommunications but to a lesser extent, is in the process of recording a reapid rate of development. Fields of utilization for spatial imagery are numerous: ocean monitoring, crops monitoring, glaciology, meteorlogy, forestry, environmental watch, geology, etc. All those fields of interest could be gathered under the generic name of "earth-watching activities" which is somewhat larger than "remote-sensing." This article aims at presenting to Korean readers the main lines of development of five major players in the field, namely : the USA, France, Japan, Europe and Canada. This is not to exclude the role played by other active players such as the former USSR and other smaller though industrious space powers.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.75-77
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• 2003

The spatial distribution of snow cover area is a crucial input to models of hydrology and climate in alpine and other seasonally snow covered areas.The objective in our study is to develop a rapidly automatic and high accuracy snow cover mapping algorithm applicable for the Tibetan Plateau which is the most sensitive about climatic change. Monitoring regional snow extent reqires higher temoral frequency-moderate spatial resolution imagery.Our algorithm is based AVHRR and MODIS data and will provide long-term fraction snow cover area map.We present here a technique is based on the multiple endmembers approach and by taking advantages of current approaches, we developed a technique for automatic selection of local reference spectral endmembers.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.381-383
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• 2003

SAR imagery offers a reliable mode of image acquisition over tropical countries for various applications. The Philippines participated in two missions to the Pacific Rim by NASA in 1996 and 2000 that saw the deployment of the AIRSAR instrument. This paper discusses the Philippine experience in the use of polarimetric and interferometric radar datasets for diverse applications, including hazards mapping, geologic and geomorphologic mapping, and land cover mapping. The results are discussed in the light of present efforts at capacity building in remote sensing, attempts at operationalizing the use of SAR for priority applications, and future ambitions in remote sensing.

• 대한원격탐사학회지
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• 제18권3호
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• pp.163-169
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• 2002

The land uses of Korean peninsula are very complicated and high-density. Therefore, the image classification using coarse resolution satellite images may not provide good results for the land cover classification. The purpose of this paper is to compare the classification accuracy of visual interpretation with that of digital image classification of satellite remote sensing data such as 20m SPOT and 30m TM. In this study, hybrid classification was used. Classification accuracy was assessed by comparing each classification result with reference data obtained from KOMPSAT-1 EOC imagery, air photos, and field surveys.

• 대한원격탐사학회지
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• 제20권3호
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• pp.215-225
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• 2004

A multistage hierarchical clustering technique, which is an unsupervised technique, was suggested in this paper for classifying large remotely-sensed imagery. The multistage algorithm consists of two stages. The 'local' segmentor of the first stage performs region-growing segmentation by employing the hierarchical clustering procedure of CN-chain with the restriction that pixels in a cluster must be spatially contiguous. The 'global' segmentor of the second stage, which has not spatial constraints for merging, clusters the segments resulting from the previous stage, using the conventional agglomerative approach. Using simulation data, the proposed method was compared with another hierarchical clustering technique based on 'mutual closest neighbor.' The experimental results show that the new approach proposed in this study considerably increases in computational efficiency for larger images with a low number of bands. The technique was then applied to classify the land-cover types using the remotely-sensed data acquired from the Korean peninsula.

• 대한원격탐사학회지
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• 제26권6호
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• pp.731-740
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• 2010

A region merging technique is suggested in this paper for the segmentation of high-spatial resolution imagery. It employs a region growing scheme based on the region adjacency graph (RAG). The proposed algorithm uses directional neighbor-line average feature vectors to improve the quality of segmentation. The feature vector consists of 9 components which includes an observation and 8 directional averages. Each directional average is the average of the pixel values along the neighbor line for a given neighbor line length at each direction. The merging coefficients of the segmentation process use a part of the feature components according to a given merging coefficient order. This study performed the extensive experiments using simulation data and a real high-spatial resolution data of IKONOS. The experimental results show that the new approach proposed in this study is quite effective to provide segments of high quality for the object-based analysis of high-spatial resolution images.