• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.6 s.97
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• pp.615-621
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• 2005

In this paper, a model for simulating synthetic aperture radar(SAR) images of earth surfaces. The earth surfaces include forest area, rice crop field, other agricultural fields, grass field, road, and water surface. At first, the backscattering models are developed for bare soil surfaces, water surfaces, short vegetation fields such as rice fields and grass field, other agriculture areas, and forest areas. Then, the SAR images are generated from the digital elevation model(DEM) and digital terrain map. The DTM includes ten parameters, such as soil moisture, surface roughness, canopy height, leaf width, leaf length, leaf density, branch length, branch density, trunk length, and trunk density, if applicable. The scattering models are verified with measurements, and applied to generate an SAR image for an area.

• Journal of Environmental Impact Assessment
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• v.7 no.1
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• pp.71-80
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• 1998

The purpose of this study is to investigate and analyze a conservation state and a sustainable use of coastal wetland in Sindu-ri Tae-an, using the plant community structure analysis and the awareness result of local residents by published paper. To investigate a forest structure in Sindu-ri area, twenty plots were set up and surveyed. The community, is divided by three groups. The divided groups are Robinia pseudoacacia(I), Pinus thunbergii-Robinia pseudoacacia(II), Robinia pseudoacacia(III). Survey site I is simple canopy layer and deteriorative forest. Survey site II is grassland and swamp, where Pinus thunbergii-Robinia pseudoacacia is dominant trees of vegetation. Robinia pseudoacacia is competition species with Pinus thunbergii in survey site II. Survey site III is barren land(sand-hill) where main species is Robinia pseudoacacia. As a result, survey II district is considered as the most suitable for the conservation of species diversity. It is proposed in this paper that the ecological nature trail would be connected in survey site I and II for environmental education. The local residents of Tae-an, where natural environment is well-conserved, prefer conservation to development of the region. In case of Tae-an, where the condition of the natural environment is well conserved and the development potential exists, the development is in harmony with the environmental education program.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.167-178
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• 2014

The populations of Pinus densiflora in South Korea were grouped into 4 types; Community of Pinus densiflora-Quercus serrata, Community of Pinus densiflora-Quercus mongolica, Community of Pinus densiflora-Fraxinus sieboldiana & Rhus javanica & Quercus mongolica and Community of Pinus densiflora-Prunus sargentii & Rhododendron mucronulatum. The Shannon diversity index was varied between 0.9171 and 1.5016, while the Similarity index was varied between 43.18 and 72.16. The species of Pinus densiflora are correlated positively significant with Carex humilis var. nana, Quercus serrata and Atractylodes ovata and negatively significant with Aster scaber and Sorbus alnifolia in order. According to the Correlation analysis, the relationship between the distribution of Pinus densiflora populations and the environment factors are closely related with the character of forest soil. Thus types for Pinus densiflora are differed. pH, Ex. K and Ex. Ca of Pinus densiflora populations effect No. of species and H'(shannon index). Canopy open effects No. of Individuals of Pinus densiflora community.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.133-144
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• 2014

This study was carried out to review the pattern of forest stand development for six Gangwondo Baekdudaegan Mountains which experienced different type and duration of intensive legal protection. Vegetation data from point sampling method were employed to classify community types by cluster analysis on the basis of the importance values of canopy tree species for the study areas. The names of classified communities were given by the composition of dominant tree species. The communities were also compared one another in terms of stand structure by species diversity index. The results indicated that National Parks (Seoraksan and Odaesan) had greater proportion of mixed mesophytic forest type which was supposed to progress further forest succession process so as to have more complex and diversified stand structure. On the other hand, ordinary forest areas (Seokbyeongsan and Deokhangsan) had greater proportion of the forest types which was dominatively composed of Quercus mongolica and Pinus densiflora. The forest types with large amount of these two species would tend to develop for relatively short period of time of 40-50 years after artificial disturbances. Hyangnobong of Natural Protection Area and Hambaeksan of Natural Ecosystem Conservation Area showed intermediate stand development pattern in between National Parks and ordinary forest areas. The period of intensive legal protection of the forest area was positively correlated with species diversity index (R=0.736), and noted that the forest which received intensive protection regulation for longer period tended to show more complex and diversified stand structure.

• Journal of the Korean Association of Geographic Information Studies
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• v.1 no.1
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• pp.99-108
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• 1998

In order to represent the surface characteristics in local meteorological model, soil type, vegetation index, surface roughness length, surface albedo and leaf area index should be prescribed on the surface process parameterization. In this study, the $1^{\circ}/1^{\circ}leaf$ area index, surface roughness length, and snow free surface albedo and fine mesh NDVI with seasonal variation derived from the satellite observation were applied to the land surface process parameterization. From comparison between with and without satellite data in the interactions between biosphere and atmosphere, land and atmosphere, the sensitivity of the simulated heat, energy and water vapor fluxes, ground temperature, wind, canopy water content, specific humidity, and precipitation fields were investigated.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.449-451
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• 2007

In the commercially managed timber lands, the information such as height, age, stand density, canopy closure and leaf area index need to be collected periodically. Stand volume is the most fundamental information in the valuation of timber, however, stand age information is the primary element of forest inventory and these two are highly correlated. Conventional method of collecting stand age information by field surveys such as ring count method is accurate; however, it is expensive, labor-intensive and time consuming. In the present study it was aimed to collect stand age information using modem techniques in a commercially managed timberland situated in Tennessee, USA. The Landsat Thematic Mapper (TM), Enhanced Thematic Mapper (ETM+) of three different periods, Shuttle Radar Topography Mission (SRTM), National elevation dataset (NED) and field inventory data were used. Normalized difference vegetation index (NDVI) and Tasselled Cap (TC) transformation techniques were applied on the TM and ETM+ data. The regression analysis was carried out to identify the correlation between stand age and NDVI, TC. In the present study about 2,469 datasets were analyzed. The $R^{2}$ value for stand age estimation was 0.713. The NDVI, TC2 and TC3 were found to produce accurate timber age information.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.1 no.1
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• pp.31-40
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• 2020

The rapid development of technologies in unmanned aerial vehicles (UAVs) has led to their use in various areas. UAVs are mainly used for commercial purposes, but their utilization is increasingly important in other areas because their operation cost is less than satellites and aerial imaging. The utilization of UAVs in the environment/ecology area is relatively new. Therefore, identifying the trends of UAV-related spatial information is significant in basic research for UAV utilization. This study quantitatively identified domestic and international research trends related to UAV utilization and analyzed research areas. An attempt was also made to identify upcoming UAV-related topics in the environment/ecology research field using text mining to analyze the bibliographic information of global research literature. Domestic UAV-related studies were classified into seven clusters where basic research on "UAV technology/industry trends" was abundant, and studies on data collection and analysis through UAV remote sensing technology have increased since 2015. Eight clusters were identified for international studies where the most active research area international was "remote sensing technology/data analysis". In addition, Canopy, Classification, Forest, Leaf Area Index, Normalized Difference Vegetation Index, Temperature, Tree, and Atmosphere appeared as the main keywords related to environment and ecology. The appearance frequencies and association strengths were high because the advancement in UAV optical sensor technology and the rapid development of image processing technology enabled the acquisition of data that could not be obtained from existing spatial information. They are recognized as future research topics as related domestic studies have begun corresponding to international research.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.3
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• pp.149-163
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• 2004

Evapotranspiration (ET) is a critical component of the hydrologic cycle which influences economic activities as well as the natural ecosystem. While there have been numerous studies on ET estimation for homogeneous areas using point measurements of meteorological variables, monitoring of spatial ET has not been possible at landscape - or watershed - scales. We propose a site-specific application of the land surface model, which is enabled by spatially interpolated input data at the desired resolution. Gyunggi Province of South Korea was divided into a regular grid of 10 million cells with 30m spacing and hourly temperature, humidity, wind, precipitation and solar irradiance were estimated for each grid cell by spatial interpolation of synoptic weather data. Topoclimatology models were used to accommodate effects of topography in a spatial interpolation procedure, including cold air drainage on nocturnal temperature and solar irradiance on daytime temperature. Satellite remote sensing data were used to classify the vegetation type of each grid cell, and corresponding spatial attributes including soil texture, canopy structure, and phenological features were identified. All data were fed into a standalone version of SiB2(Simple Biosphere Model 2) to simulate latent heat flux at each grid cell. A computer program was written for data management in the cell - based SiB2 operation such as extracting input data for SiB2 from grid matrices and recombining the output data back to the grid format. ET estimates at selected grid cells were validated against the actual measurement of latent heat fluxes by eddy covariance measurement. We applied this system to obtain the spatial ET of the study area on a continuous basis for the 2001-2003 period. The results showed a strong feasibility of using spatial - data driven land surface models for operational monitoring of regional ET.

• Korean Journal of Environment and Ecology
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• v.4 no.1
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• pp.23-32
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• 1990

To investigate the structure of the pine forest community and the conservation of pine forest in Mt. Sokri, twenty plots of 500$m^2$ size set up by the clumped sampling method. The classification by TWINSPAN and DCA ordination were applied to the study area in order to classify them into several groups based on environmental variables. The plant community was not classified into several groups by above methods in this study area. The successional trends of tree species by both techniques seem to be from Pinus densiflora through Quercus serrata, Fraxinus sieboldiana, Q. aliena, Sorbus alnifolia, Prunus sargentii to Carpinus laxiflora, C. cordata in the canopy layer. and from Rhus trichocarpa, Lindera obtusiloba through Styrax obassia, Acer pseudosieboldiana, Symplocos chinensis for. pilosa to L. erythrocarpa, Viburnum erosum in the understory layer. Pinus densiflora community shall be conserved by the disclimax method, i. e. the broadleaf vegetation in the underlayer of the pine community should be cleared out.

• Journal of Korean Society of Forest Science
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• v.103 no.1
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• pp.12-22
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• 2014

This study was carried out to classify forest communities and to aggregate forest cover types for the complex and diversified natural forest areas of Hwangaksan, Bakseoksan, Deogyusan, and Jirisan in southern region of Baekdudaegan Mountains. The vegetation data were collected by point-centered quarter sampling method. Eight hundred fifty one sample points were subjected to cluster analysis to classify 18 forest communities, which were aggregated into 7 representative forest cover types on the basis of community similarity from composition of canopy species. They were mixed mesophytic forest cover type, the others deciduous forest cover type, Quercus variabilis-Quercus serrata cover type, Quercus mongolica cover type, Pinus densiflora cover type, Carpinus laxiflora cover type, and Abies koreana cover type. The Quercus mongolica cover type was most widely distributed in the study areas, and this cover type tended to occur in the place of higher altitude as latitude was getting lower. Mixed mesophytic forest and the others deciduous forest cover type were commonly distributed in the areas of valley, on the other hand, Quercus mongolica cover type and Pinus densiflora cover type tended to be distributed in the areas of ridge.