• Journal of The Geomorphological Association of Korea
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• v.28 no.1
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• pp.83-99
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• 2021

Burn severity analysis using satellite imagery has high capabilities for research and management in inaccessible areas. We extracted the forest fire area of the DMZ (Demilitarized Zone) in the western Imjin Estuary which is restricted to access due to the confrontation between South and North Korea. Then we analyzed the forest fire severity and recoverability using atmospheric corrected Surface Reflectance Level-2 data collected from Landsat-8 OLI (Operational Land Imagery) / TIRS (Thermal Infrared Sensor). Normalized Burn Ratio (NBR), differenced NBR (dNBR), and Relative dNBR (RdNBR) were analyzed based on changes in the spectral pattern of satellite images to estimate burn severity area and intensity. Also, we evaluated the recoverability after a forest fire using a land cover map which is constructed from the NBR, dNBR, and RdNBR analyzed results. The results of dNBR and RdNBR analysis for the six years (during May 30, 2014 - May 30, 2020) showed that the intensity of monthly burn severity was affected by seasonal changes after the outbreak and the intensity of annual burn severity gradually decreased after the fire events. The regrowth of vegetation was detected in most of the affected areas for three years (until May 2020) after the forest fire reoccurred in May 2017. The monthly recoverability (from April 2014 to December 2015) of forests and grass fields was increased and decreased per month depending on the vegetation growth rate of each season. In the case of annual recoverability, the growth of forest and grass field was reset caused by the recurrence of a forest fire in 2017, then gradually recovered with grass fields from 2017 to 2020. We confirmed that remote sensing was effectively applied to research of the burn severity and recoverability in the DMZ. This study would also provide implications for the management and construction statistics database of the forest fire in the DMZ.

• Korean Journal of Remote Sensing
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• v.36 no.2_2
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• pp.249-261
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• 2020

Coastal monitoring using multiple platforms/sensors is a very important tools for accurately understanding the changes in offshore marine environment and disaster with high temporal and spatial resolutions. However, integrated observation studies using multiple platforms and sensors are insufficient, and none of them have been evaluated for efficiency and limitation of convergence. In this study, we aimed to suggest an integrated observation method with multi-remote sensing platform and sensors, and to diagnose the utility and limitation. Integrated in situ surveys were conducted using Rhodamine WT fluorescent dye to simulate various marine disasters. In September 2019, the distribution and movement of RWT dye patches were detected using satellite (Kompsat-2/3/3A, Landsat-8 OLI, Sentinel-3 OLCI and GOCI), unmanned aircraft (Mavic 2 pro and Inspire 2), and manned aircraft platforms after injecting fluorescent dye into the waters of the South Sea-Yeosu Sea. The initial patch size of the RWT dye was 2,600 ㎡ and spread to 62,000 ㎡ about 138 minutes later. The RWT patches gradually moved southwestward from the point where they were first released,similar to the pattern of tidal current flowing southwest as the tides gradually decreased. Unmanned Aerial Vehicles (UAVs) image showed highest resolution in terms of spatial and time resolution, but the coverage area was the narrowest. In the case of satellite images, the coverage area was wide, but there were some limitations compared to other platforms in terms of operability due to the long cycle of revisiting. For Sentinel-3 OLCI and GOCI, the spectral resolution and signal-to-noise ratio (SNR) were the highest, but small fluorescent dye detection was limited in terms of spatial resolution. In the case of hyperspectral sensor mounted on manned aircraft, the spectral resolution was the highest, but this was also somewhat limited in terms of operability. From this simulation approach, multi-platform integrated observation was able to confirm that time,space and spectral resolution could be significantly improved. In the future, if this study results are linked to coastal numerical models, it will be possible to predict the transport and diffusion of contaminants, and it is expected that it can contribute to improving model accuracy by using them as input and verification data of the numerical models.

• Korean Journal of Remote Sensing
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• v.37 no.5_2
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• pp.1329-1340
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• 2021

The intertidal zone, which is a transitional zone between the ocean and the land, requires continuous monitoring as various changes occur rapidly due to artificial activity and natural disturbance. Monitoring of coastal topography changes using remote sensing method is evaluated to be effective in overcoming the limitations of intertidal zone accessibility and observing long-term topographic changes in intertidal zone. Most of the existing coastal topographic monitoring studies using remote sensing were conducted through high spatial resolution images such as Landsat and Sentinel. This study extracted the waterline using the NDWI from the GOCI-II (Geostationary Ocean Color Satellite-II) data, identified the changes in the intertidal area in Gyeonggi Bay according to various tidal heights, and examined the utility of DEM generation and topography altitude change observation over a short period of time. GOCI-II (249 scenes), Sentinel-2A/B (39 scenes), Landsat 8 OLI (7 scenes) images were obtained around Gyeonggi Bay from October 8, 2020 to August 16, 2021. If generating intertidal area DEM, Sentinel and Landsat images required at least 3 months to 1 year of data collection, but the GOCI-II satellite was able to generate intertidal area DEM in Gyeonggi Bay using only one day of data according to tidal heights, and the topography altitude was also observed through exposure frequency. When observing coastal topography changes using the GOCI-II satellite, it would be a good idea to detect topography changes early through a short cycle and to accurately interpolate and utilize insufficient spatial resolutions using multi-remote sensing data of high resolution. Based on the above results, it is expected that it will be possible to quickly provide information necessary for the latest topographic map and coastal management of the Korean Peninsula by expanding the research area and developing technologies that can be automatically analyzed and detected.

• Korean Journal of Remote Sensing
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• v.34 no.6_2
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• pp.1165-1178
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• 2018

Collapse of an Antarctic ice shelf and its flow velocity changes has the potential to reduce the restraining stress to the seaward flow of the Antarctic Ice Sheet, which can cause sea level rising. In this study, variations in ice velocity from 2000 to 2017 for the Nansen Ice Shelf in East Antarctica that experienced a large-scale collapse in April 2016 were analyzed using Landsat-7 Enhanced Thematic Mapper Plus (ETM+) and Landsat-8 Operational Land Imager (OLI) images. To extract ice velocity, image matching based on orientation correlation was applied to the image pairs of blue, green, red, near-infrared, panchromatic, and the first principal component image of the Landsat multispectral data, from which the results were combined. The Landsat multispectral image matching produced reliable ice velocities for at least 14% wider area on the Nansen Ice Shelf than for the case of using single band (i.e., panchromatic) image matching. The ice velocities derived from the Landsat multispectral image matching have the error of $2.1m\;a^{-1}$ compared to the in situ Global Positioning System (GPS) observation data. The region adjacent to the Drygalski Ice Tongue showed the fastest increase in ice velocity between 2000 and 2017. The ice velocity along the central flow line of the Nansen Ice Shelf was stable before 2010 (${\sim}228m\;a^{-1}$). In 2011-2012, when a rift began to develop near the ice front, the ice flow was accelerated (${\sim}255m\;a^{-1}$) but the velocity was only about 11% faster than 2010. Since 2014, the massive rift had been fully developed, and the ice velocity of the upper region of the rift slightly decreased (${\sim}225m\;a^{-1}$) and stabilized. This means that the development of the rift and the resulting collapse of the ice front had little effect on the ice velocity of the Nansen Ice Shelf.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.530-537
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• 2000

Quality characteristics of strawberry jams made of 2 different strawberry cultivars, Bogyo-joseng and Suhong, with 25, 50, 75, 100% fructo-oligosaccharide in place of sucrose were evaluated. Moisture content of Suhong jam was higher than Bogyo-joseng jam. pH of Bogyo-joseng and Suhong jam was not different. The lightness, redness and yellow-ness of Bogyo-joseoung jam were higher than those of Suhong jam. Spreadmeter value of jams decreased with addition of fructo-oligosaccharide. The sweetness of Suhong jam was higher than Bogyo-joseng. Reducing sugar content of Suhong jam was higher than Bogyo-joseng jam. More of fructo-oligosaccharide added, reducing sugar content of jam increased. Residual anthocyanin in Bogyo-joseng strawberry jam was decreased by addition of fructo-oligosaccharide. However, the residual anthocyanin content of Suhong strawberry jams with fructo-oligosaccharide was lower than that of sugar-only control jam with an exception of 50% fructo-oli-gosaccharide jam. The 50% fructo-oligosaccharide jam had a higher residual anthocyanin content than sugar-only jam. As the addition rate of fructo-oligosaccharide increased, springiness and cohesiveness of jam increased, while resilience decreased. In sensory evaluation, Bogyo-joseng strawberry jams obtained highest score with 50% fructo-oligosaccharide, while Suhong strawberry jam was favored most with 25% fructo-oligosaccharide.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.297-306
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• 2004

Heat shock proteins (HSPs) were induced in cells in the thermal stress, and the HSP90 family is one of the major classes of HSPs. Gene encoding HSPs have been characterized from various mammals and piscine. We have cloned and sequenced the HSP90 cDNA from a brain cDNA library constructed from flounder (Paralichthys oliThe result of sequence analysis shows it to be the HSP90~. The nucleotide sequence of the HSP90$\beta$ was composed of 2791 long, encoding 726 amino acid residues. The flounder hsp90$\beta$ gene showed very high sequence homology with hsp90f3 of European sea bass (96.6%), zebrafish (92.9%), Atlantic salmon (92.0%) and human (89.5%). We also constructed a phylogenetic tree based on HSP90 amino acid sequences from vertebrate species. Gene-specific primers were selected and used in RT-PCR reactions to measure the basal hsp90$\beta$ mRNA. The hsp90f3 gene is constitutively expressed at a fairly high level in all examined tissues (brain, liver, kidney, muscle, and spleen). In order to express protein of flounder hsp90$\beta$ in E. coli, we used the His-tagged pETvector. Then, the expression of flounder HSP90$\beta$ was confirmed by Western blot analysis.

• Korean Journal of Ichthyology
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• v.20 no.1
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• pp.13-20
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• 2008

Internal and external reproductive parameters of the striped bitterling, Acheilognathus yamatsutae were compared. Internal reproductive parameters was used gonadosomatic index (GSI), hepatosomatic index (HSI) and gonadal development stage. External reproductive parameters was used ovipositor in female and pearl organ, dorsal and caudal fin nuptial color in male. The GSI and HSI of the female and male showed highest in February. Gonadal development was observed mainly ripe and spawning/spent stage in February to May. The ovipositor length index (OLI) of the female showed highest in March to April. Pearl organ number and expression rate of the male showed highest in February to May. Dorsal fin nuptial color expression rate and index (NCI-DF) showed highest in February to May. Caudal fin nuptial color expression rate and index(NCI-CF) showed highest in February to April. The study suggested same change of internal and external reproductive parameters in female and male.

• Review of Culture and Economy
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• v.17 no.2
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• pp.29-62
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• 2014

Game industry, one of cultural-content industry which is considered as a typical knowledge-based industry and creative industry, is not like the overseas expansion of traditional manufacture, and has different strategy and performance of export expansion through product or project-based strategy. Therefore, it should be approached by each content unit, and necessary to look at the factors that make their decision makings of foreign market entry vary. This study focuses on discovering creativity, absorptive capacity and strategic orientation(market orientation and innovation orientation) which affect the difference of distribution's decision making of entry into foreign market in game industry This paper examined 252 cases of online games in order to investigate creativity, absorptive capacity and strategic orientations for each foreign market and what entry type(among licensing, joint distribution, exclusive distribution) they chose according to the products developed in team level. This helps us analyze the factors affecting market orientation and innovation orientation in the perspectives of creativity and absorptive capacity in comprehensive way, and notice the phenomena which use different foreign distribution strategy though there are company incorporated abroad and their results. This study supplements the limit of the existing Resource-Based View, Resource-Dependent View, and traditional international business theories such as Transaction Cost Theory or OLI Paradigm(Eclectic Framework), and proves how company could reduce asymmetry of uncertainty and information in creative industry and whether they accomplish successful overseas expansion according to strategic orientations.

• The Journal of Engineering Geology
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• v.31 no.3
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• pp.395-432
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• 2021

Groundwater recharge rates vary widely by location and with time. They are difficult to measure directly and are thus often estimated using simulations. This study employed frequency and regression analysis and a classification and regression tree (CART) algorithm in a machine learning method to estimate groundwater recharge. CART algorithms are considered for the distribution of precipitation by subbasin (PCP), geomorphological data, indices of the relationship between vegetation and landuse, and soil type. The considered geomorphological data were digital elevaion model (DEM), surface slope (SLOP), surface aspect (ASPT), and indices were the perpendicular vegetation index (PVI), normalized difference vegetation index (NDVI), normalized difference tillage index (NDTI), normalized difference residue index (NDRI). The spatio-temperal distribution of groundwater recharge in the SWAT-MOD-FLOW program, was classified as group 4, run in R, sampled for random and a model trained its groundwater recharge was predicted by CART condidering modified PVI, NDVI, NDTI, NDRI, PCP, and geomorphological data. To assess inter-rater reliability for group 4 groundwater recharge, the Kappa coefficient and overall accuracy and confusion matrix using K-fold cross-validation were calculated. The model obtained a Kappa coefficient of 0.3-0.6 and an overall accuracy of 0.5-0.7, indicating that the proposed model for estimating groundwater recharge with respect to soil type and vegetation cover is quite reliable.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.4
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• pp.1-14
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• 2019

The 1st Forest Health Management survey was conducted to examine the health of the forests in Korea. However, in order to understand the health of the forests, which account for 63.7% of the total land area in South Korea, it is necessary to comprehensively spatialize the results of the survey beyond the sampling points. In this regard, out of the sample points of the 1st Forest Health Management survey in Gyeongbuk area, 78 spots were selected. For these spots, the species diversity index was selected from the survey sections, and the spatial interpolation method was applied. Inverse distance weighted (IDW), Ordinary Kriging and Ordinary Cokriging were applied as spatial interpolation methods. Ordinary Cokriging was performed by selecting vegetation indices which are highly correlated with species diversity index as a secondary variable. The vegetation indices - Normalized Differential Vegetation Index(NDVI), Leaf Area Index(LAI), Sample Ratio(SR) and Soil Adjusted Vegetation Index(SAVI) - were extracted from Landsat 8 OLI. Verification was performed by the spatial interpolation method with Mean Error(ME) and Root Mean Square Error(RMSE). As a result, Ordinary Cokriging using SR showed the most accurate result with ME value of 0.0000218 and RMSE value of 0.63983. Ordinary Cokriging using SR was proven to be more accurate than Ordinary Kriging, IDW, using one variable. This indicates that the spatial interpolation method using the vegetation indices is more suitable for spatialization of the biodiversity index sample points of 1st Forest Health Management survey.