• Journal of Korean Society for Geospatial Information Science
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• v.7 no.2 s.14
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• pp.101-110
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• 1999

Recently, there are a lot of studies to use a satellite image data in order to investigate a simultaneous change of a wide range area as a lake. However, in many cases of the water quality research there is one problem occured when extracting the water quality factors from the satellite image data because the atmosphere scattering exert a bad influence on a result of analysis. In this study, an attempt was made to select the relative atmospheric correction method, extract the water quality factors from the satellite image data. And also, the time-series analysis of the water quality factors was performed by using the multi-temporal image data.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.517-522
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• 2003

Exact estimation of evapotranspiration is important to understand natural phenomena and social issues associated with the climate such as irrigation scheme, reservoir water management, and many other meteorological and climatological problems. To overcome limits of point measurement of evapotranspiration, several models have been developed through the techniques of remote sensing and Geographical Information System. SEBAL model is one of them, based on the energy balance equation, and it has a lot of advantages such as that it requires relatively small empirical relations. In this study, the SEBAL model has been calibrated and validated in Geumgang upper basin, Bochung-stream basin, Korea with 5 satellite images Landsat 5 TM. In validation, the results of SEBAL model were compared with those by Merton method. After validation, the spatial and temporal characteristics of the distribution of evapotranspiration within the basin were analyzed with 3 factors, the aspect of slope, the angle of slope, and the land cover.

• Journal of Sensor Science and Technology
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• v.6 no.2
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• pp.106-114
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• 1997

In this paper, we propose an efficient coding method of remotely sensed satellite image using region classification and interband prediction. This method classifies each pixel vector considering spectral characteristics of satellite image data. Then we perform the classified intraband VQ to remove spatial (intraband) redundancy for a reference band image. To remove interband redundancy effectively, we perform the classified interband prediction for the remaining band images. Experiments on LANDSAT TM satellite image show that coding efficiency of the proposed method is better than that of the conventional Gupta's method.

• Journal of Forest and Environmental Science
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• v.31 no.4
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• pp.288-296
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• 2015

In many very high density cities in Asia in which there is limited area to expand, growth is forced upward as well as outward. Densely packed detached houses and low-rise buildings are replaced by lower density high-rises, leaving open spaces between high-rise buildings. Through this process, areas that formerly did not have much green space gain valuable green spaces, and new ecological corridors and patches are created. In this study, the demographic and housing-type changes of Wonju City were delineated using land use maps, aerial images, census data, and other administrative data. Green area changes were calculated using land cover data derived from multi-year Landsat TM satellite imagery. The values were then compared against demographic and housing-type changes for each administrative unit. The overall results showed a decrease of forested area in the city and an increase of developed area. Urban sprawl was clearly visible in many of the suburban areas. However, as expected, we also detected areas in which greenness did not decrease when the population greatly increased. These areas were characterized by residential building complexes of ten or more stories. If an equal number of housing units had been built as detached houses, these areas would not have kept as much green space. Our research result showed that high-density and high-rise residential structures can offer an alternative means to protect or create urban green spaces in high-density urban environments.

• Journal of Korean Society of Rural Planning
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• v.10 no.1 s.22
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• pp.19-26
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• 2004

In this paper, forestry area change effect on the soil erosion in Asan lake watershed was estimated. Temporal variations of land use in the study watershed were analyzed from Landsat-5 TM remote sensing images. Geographic Information System (GIS) combined with Universal Soil Loss Equation (USLE) was used to estimate the soil erosion of Asan lake watershed. Spatial data for each USLE factors was obtained from the Landsat-5 TM remote sensing images and 1/25,000 scale digital contour maps. Sediment yield to Asan lake was estimated by sediment delivery ratio and sediment accumulation in lake was estimated by trap efficiency. The estimation methods were validated for sediment accumulation in Asan lake. From the hydrographic survey from 1974 to 2003 for Asan lake, sediment accumulation was measured. The estimated accumulation sediment of 303,569ton/yr showed similar value with observed of 295,888ton/yr. From the validated estimation methods, the increasing amount of soil erosion when 1% of forest area in Asan lake watershed decreases was calculated from 12.91 to 1482.05ton/yr.

• Korean Journal of Remote Sensing
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• v.31 no.4
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• pp.303-319
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• 2015

The objectives of this paper are to measure surface imperviousness using three different classification methods: per-pixel, sub-pixel, and object-oriented classification. They are tested on high-spatial resolution QuickBird data at 2.4 meters (four spectral bands and three principal component bands) as well as a medium-spatial resolution Landsat TM image at 30 meters. To measure impervious surfaces, we selected 30 sample sites with different land uses and residential densities across image representing the city of Phoenix, Arizona, USA. For per-pixel an unsupervised classification is first conducted to provide prior knowledge on the possible candidate spectral classes, and then a supervised classification is performed using the maximum-likelihood rule. For sub-pixel classification, a Linear Spectral Mixture Analysis (LSMA) is used to disentangle land cover information from mixed pixels. For object-oriented classification several different sets of scale parameters and expert decision rules are implemented, including a nearest neighbor classifier. The results from these three methods show that the object-oriented approach (accuracy of 91%) provides more accurate results than those achieved by per-pixel algorithm (accuracy of 67% and 83% using Landsat TM and QuickBird, respectively). It is also clear that sub-pixel algorithm gives more accurate results (accuracy of 87%) in case of intensive and dense urban areas using medium-resolution imagery.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.2
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• pp.163-168
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• 1995

There are four types of color model to repesent color, which are RGB, IHS, CMY, and YIQ color model. RGB color model is the designation of the digital numbers(DNs) of the three primary colors(red, green, and blue), which are used to produce color images on color monitors. IHS color model is the designation of in-tensity, hue, and saturation(IHS). An advantage of considering color in terms of IHS over that of RGB is arrives more easily at a desired color product mathematically. In this study, authors use the IHS transformation and in-tensity-adjustment method to produce the color map images with Landsat TM and scanned map image. And, authors suggest the problems and their solutions when users produce the desired new images with satellite images and map images.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.231-236
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• 1997

Observation for hot water spread has been carried out by such activites as sampling of water with ship, etc, until now It was required further to have new probe methodologies in such issues as simultaneity, great-spheric nature, and economics due to many hindering ele- ments such as spread speed of hot waste water, weather conditions, cost and expenses, scope and location determinations. However, it was believed that satellite could be utilized to monitor spread of water temperature and spread level in more quick and correct way than existing one, because it would be possible to supervise and detect marine environment within significantly short period if analyzed by means of satellite images. Therefore, this study is taken into account to flow and spread conditions of hot waste water, survey of water temperature, by means of satellite images.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.303-315
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• 2012

This study developed a wetland inventory describing the characteristics and change of Nakdong estuary wetland ecosystem. The data which are used to develop the inventory are Landsat TM(April 1, 1986; June 23, 1987; June 18, 1997), Kompsat(Jan. 12, 2008) and LiDAR(March 1, 2009) images and published monitoring data of Busan metropolitan city. The developed inventory was utilized for the classification of wetland cover, the spatiotemporal analysis of wetland and landscape pattern, the distribution of benthos species etc. Furthermore, the developed 3 dimensional wetland map showed a better way to delineate wetland boundary and understand wetland dynamics. Considering these results, it's concluded that it is possible to use the similar techniques for the development of wetland inventory in Korea.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.4
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• pp.411-420
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• 1999

Coastal development and reclamation work make environment of shore destroy, such as rapid change of land use and destruction of wet-land and ocean ecosystem. Therefore new technique to detect change have been needed. This study designed new change detection method and applied to study area. The change detection image and quantitative change area by each classes are calculated. Also, this study can use the basic idea-determination data for coastal development and city plan as the sense of sight by changed images that changed from any land-cover to any land-cover between two dates.