• Korean Journal of Remote Sensing
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• v.25 no.2
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• pp.113-126
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• 2009

With high temporal resolution, four times receiving during a day, MODIS images from Terra and Aqua satellites provide several advantages for monitoring spacious land. Especially, diverse MODIS products related to land, atmosphere, and ocean have been provided with radiance MODIS images. The products such as surface reflectance, NDVI, cloud mask, aerosol etc. are based on theoretical algorithms developed in academic areas. Comparing with other change detection studies mainly using the vegetation index, this study investigated temporal surface reflectance of landcovers for five years from 2004 to 2008. The near infrared (NIR) reflectance in urbanized and burned areas showed considerable difference before and after events. The specific characteristics of surface reflectance temporal profiles are possibly useful for the detection of landcover changes and classification.

• Journal of The Geomorphological Association of Korea
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• v.25 no.2
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• pp.1-14
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• 2018

The main objective of this paper is to classify properties of the locational environment for each debris type by calculating likelihood ratio based on the correlation between the distributions for each type of debris landform. A total of 8 thematic maps, like as elevation, slope, aspect, curvature, topographic wetness index (TWI), soil drainage, geology, and landcover including with GIS spatial information generally used in this type of debris landform analysis. The results of this study showed that the block stream had a high likelihood ratio compared to talus in areas with relatively high elevation; and concerning slope, the block stream had a high likelihood ratio in a relatively low region than talus. Concerning aspect, a clear correlation could not be analyzed for each debristype, and concerning curvature, the block stream displayed a developed slope on the more concave valley than the talus. Analysis concerning TWI, the block stream displayed a higher likelihood ratio in wider sections than talus, and concerning soil drainage, the talus and block stream both displayed a high likelihood ratio in regions with well-drained soil. The talus displayed a high likelihood ratio in the order of metamorphic rocks, sedimentary rocks, and granite, while the block stream displayed a high likelihood ratio in the order of volcanic rocks, granite, and sedimentary rocks. In addition, concerning landcover, the likelihood ratio had the most concentrated distributed compared to natural bare land only concerning talus. Based on the likelihood ratio result, it can be used as basic data for extracting the possible areas of distribution for each debris type through the GIS spatial integration method.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.499-499
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• 2002

The goal of this study is to apply and evaluate the precipitation outflow in river basin using satellite data and GIS for proposing the efficient watershed management method. Not only precipitation outflow data but also various spatial data such as digital map, soil map, geologic map and multi-temporal TM images were used. Using landcover classification result and soil map were applied to estimate the average CN. The CN value of 63.37 by SCS method was produced in AMC-2 condition otherwise the result of direct estimation with observation method was 63 CN value. The relative error of two results was 0.59%. It can be possible to apply the satellite data for precipitation outflow analysis. For more accurate and credible analysis of this, the more multi-temporal satellite and real observation data will be needed.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.126-129
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• 2005

Change detections is carried out under the assumption that pixel boundaries of geometrically corrected time series satellite images cover the same location. However that assumption can be wrong when shifts in the pointing direction of a satellite sensor occurs. Currently, although the influence of misregistration on landcover change detection has been investigated, there has been little research on the influence of pointing direction shifts of a satellite sensor. In this study, a simple method for reducing the effects of pointing direction shifts of a satellite sensor is proposed: the classification of two ASTER images was carried out using the linear spectral mixture analysis, the two classification results were resampled into a geometrically fixed grid, and then the change detection of the two ASTER images was carried out by comparing the resampled classification results of the two images. The proposed method showed high performance in discriminating between changed areas and unchanged areas by removing the pointing direction shifts of a satellite sensor.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.646-649
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• 2004

LiDAR(Light Detection and Ranging) system can record intensity data as well as range data. Recently, LiDAR intensity data is widely used for landcover classification, ancillary data of feature extraction, vegetation species identification, and so on. Since the intensity return value is associated with several factors, same features is not consistent for same flight or multiple flights. This paper investigated correlation between intensity and range data. Once the effects of range was determined, the single flight line normalization and the multiple flight line normalization was performed by an empirical function that was derived from relationship between range and return intensity

• Proceedings of the KSRS Conference
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• v.1
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• pp.47-50
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• 2006

Tsunami disaster caused great damages and very large victims especially when occurs in urban area along coastal region. Therefore information of evacuation in a map is very important for disaster preparedness in order to minimize the number of victims in affected area. Here, information generated from remote sensing satellite data (SPOT 5 and DEM) and secondary data (administration boundary and field survey data) are used to simulate evacuation route and to produce a map for Padang City. Vulnerability and evacuation areas are determined based on DEM. Landuse/landcover, accessibility areas, infrastructure and landmark are extracted from SPOT 5 data. All the data obtained from remote sensing and secondary data are integrated using geospatial modelling to determine evacuation routes. Finally the simulation of evacuation route in Padang City for tsunami preparedness is provided based on the parameters derived from remote sensing data such as distances from shelters, save zones, city's landmarks and the local community experiences how they can survive with the disaster.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.1
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• pp.51-58
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• 2002

Since planning of green-network is deeply being discussed, natural environmental disruption from an enlarged civilization is causing serious problems for urban communities. The purpose of this research is to support green-network infrastructure of Gangnam-gu, Seoul, considering ecological environmental planning for urban parks. The Methodologies for this study are landcover classification, NDVI and subjective analysis, and residents' survey. Findings of this research are as follows : 1) Based on the results, the area adjacent to Daemo mountain shows significant differences between 1985 and 1999. These results imply that the green space has been decreasing and deeply destroying. 2) Residents' survey shows that people want to live with wild animals and plants in the natural park. Future development planning of urban park should consider primary factors : ecosystem, increasing inhabitants' participation.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.1
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• pp.65-73
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• 2013

FDB(Feature DataBase) attributes have been produced by using the resource data prior to the year 2002. Due to this reason, the attributes need to be updated to the up-to-date ones. In this regards, this study focuses on the way of finding areas whose attributes need to be updated. Forest and crop classes were chosen as target classes among FDB features. MODIS Landcover data and FDB are, first, compared to detect the changed forest and crop areas from 2001 to 2008. Then, vegetation vitality changes are analyzed using MODIS annual NDVI data. Based on the change detection and the vegetation vitality analysis, the index of area selection for updating FDB attributes is proposed in this study.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.49-49
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• 2019

국내의 하천생태계의 다양성 확보를 위한 유역 단위 하천환경 개선에 대한 관심은 꾸준히 증가하고 있는 추세이다. 하천환경 조사와 관리차원에서 적극적인 투자와 노력이 필요하며 이를 위해서는 현 상태를 확인하고 판단하는 것이 매우 중요한 부분이다. 초분광 영상은 하천의 하상재료, 수심 및 식생분포와는 관련 없는 고유의 분광정보 특성을 포함하고 있다. 본 연구는 한국건설기술연구원의 안동 하천실험센터의 실험수로에서 하천에서 흔히 볼 수 있는 대표적인 하상재료를 분포시켜 초분광영상과 RGB 영상자료를 취득한 후 각각의 하상재료의 특성에 대해 분석하였다. 실험수로는 폭 0.9 m, 길이 10 m수로에 모래, 큰돌, 흰자갈, 갈대, 식생 5가지 종류를 좌우, 상하대칭으로 분포시켰으며, 수심에 따라 취득된 영상정보의 특성값이 얼마나 변경되는지에 대해 파악하였다. 본 연구를 통해 하천의 다양한 하상재료에 대한 구분과 수리조건에 따른 분광정보의 왜곡, 계절별 식생특성 파악 및 분류에 대한 결과를 확인할 수 있을 것으로 판단된다.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.52-54
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• 2022

Aerial images are being one of the important aspects of satellite imagery, delivers effective information on landcovers. Their special characteristics includes the viewpoint from space which clarifies data related to land examining processes. Aerial images taken by satellites employed radio waves to wirelessly transmit images to ground stations. Due to transmission errors, images get distorted and unable to perform in landcover examining. This paper proposes an aerial image enhancement method using deep autoencoders. A properly trained autoencoder can enhance an aerial image to a considerable level of improvement. Results showed that the achieved enhancement is better than that was obtained from traditional image denoising methods.