• Title/Summary/Keyword: 공간적 이질성

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Development of a Biophysical Rice Yield Model Using All-weather Climate Data (MODIS 전천후 기상자료 기반의 생물리학적 벼 수량 모형 개발)

  • Lee, Jihye;Seo, Bumsuk;Kang, Sinkyu
    • Korean Journal of Remote Sensing
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    • v.33 no.5_2
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    • pp.721-732
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    • 2017
  • With the increasing socio-economic importance of rice as a global staple food, several models have been developed for rice yield estimation by combining remote sensing data with carbon cycle modelling. In this study, we aimed to estimate rice yield in Korea using such an integrative model using satellite remote sensing data in combination with a biophysical crop growth model. Specifically, daily meteorological inputs derived from MODIS (Moderate Resolution imaging Spectroradiometer) and radar satellite products were used to run a light use efficiency based crop growth model, which is based on the MODIS gross primary production (GPP) algorithm. The modelled biomass was converted to rice yield using a harvest index model. We estimated rice yield from 2003 to 2014 at the county level and evaluated the modelled yield using the official rice yield and rice straw biomass statistics of Statistics Korea (KOSTAT). The estimated rice biomass, yield, and harvest index and their spatial distributions were investigated. Annual mean rice yield at the national level showed a good agreement with the yield statistics with the yield statistics, a mean error (ME) of +0.56% and a mean absolute error (MAE) of 5.73%. The estimated county level yield resulted in small ME (+0.10~+2.00%) and MAE (2.10~11.62%),respectively. Compared to the county-level yield statistics, the rice yield was over estimated in the counties in Gangwon province and under estimated in the urban and coastal counties in the south of Chungcheong province. Compared to the rice straw statistics, the estimated rice biomass showed similar error patterns with the yield estimates. The subpixel heterogeneity of the 1 km MODIS FPAR(Fraction of absorbed Photosynthetically Active Radiation) may have attributed to these errors. In addition, the growth and harvest index models can be further developed to take account of annually varying growth conditions and growth timings.

Monsoon Inflow as a Major Source of In-lake Phosphorus (호수내 인의 주요원으로 몬순 유입수)

  • An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.33 no.3 s.91
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    • pp.222-229
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    • 2000
  • Spatial and temporal variation of phosphorus in response to intensity of summer monsoon was evaluated in Taechung Reservoir during 1993${\sim}$1994. Total phosphorus (TP) averaged 31 ${\mu}$g/l during the study and varied from 6 to 197 ${\mu}$g/l. Concentrations of TP were highest in the headwaters during the monsoon of July${\sim}$August 1993, and these values were mainly made of particulate P and were closely associated (R$^{2}$=0.74, p<0.001) with high inorganic suspended solids (NVSS). In-lake TP in the headwaters was mainly influenced by the watershed runoff and declined toward the dam. Values of TP downlake was only one-fifth of the peak in the headwaters and had no correlation with NVSS. In 1994, inlake TP was markedly lower relative to 1993 and showed low spatial and temporal variation. Maximum TP during monsoon 1994 in the headwaters and mid-lake was 72% and 52% lower, respectively, than in those two zones in 1993 whereas TP downlake was similar between the two years. These results suggest that temporal variation downlake is much less influenced by seasonal inflow compared to the haedwaters. In 1993, mean TP before fall overturn, based on average value for all sites, was significantly (t=5.99, p<0.001) greater than the mean after fall overturn, whereas in 1994 mean TP after fall overturn (32 ${\mu}$g/l) was greater. This outcome indicates that in 1993 major P-input originated from the external source from the watershed during the intense monsoon, whereas in 1994 internal processes dominated during the weak monsoon. Overall data suggest that annual budget of inlake P is regulated by intensity of the summer monsoon, and phosphorus data measured at single site near the dam or headwater zone may not be represent seasonal trends of the system due to large spatial variation of Taechung Reservoir.

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Essay on the Community Archpe ('마을아르페'(Community Archpe) 시론 - 마을 차원의 "책, 기록, 역사 그리고 치유와 창업의 커뮤니티"를 위한 제안-)

  • Lee, Young-Nam
    • The Korean Journal of Archival Studies
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    • no.18
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    • pp.221-254
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    • 2008
  • Community Archpe is . Community Archpe is as close as a kind of a complex of culture space or community center which puts individuals and small community together with culture soil in a central position. For example Community Archpe can include community library, community archive, community historical center, community recovery center, community commencement of an enterprise center, etc. We need small library, archive and historian rather than big scale institution and professional system to take care of culture soil which belongs to an individual and community. Community Archpe is located in coordinates of two intention points. First intention is, a 'Heterogenous Smithy'. Heterogeneity deals with Community Archpe's life. Second intention is, a 'Feminine Smithy'. Community Archpe can be a recovery community when we are in the recovery context, which understand and support a person through archives and history. Then, what can Community Archpe do? First, it can be a new movement of the community. Second, it can also be a centripetal point of classic life. Community Archpe surly locates in the central of Community. Therefore, it will be a cultural literary soil and be a smithy of community history and culture. Thus Community Archpe will change a lot of things on people's life. Community Archpe will be a small happiness to ordinary people, even though it is not a state organ realizing large values.

A Study on the Tourist Accommodation Shape Strategy at the Mt. Kumgang International Tourism Zone (국제관광특구의 관광숙박시설 유형전략에 관한 연구 -금강산 국제관광특구를 중심으로-)

  • Shim, Hong-Bo
    • Proceedings of the Korea Contents Association Conference
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    • 2006.11a
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    • pp.750-754
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    • 2006
  • Reunification and economic development are discussed as the national visions of the Korean Peninsula in the 21st century. In particular, the tourism industry must be included as one of goals pursued under these visions because tourism indeed seeks for the happiness and peace of human beings. Mt. Kumgang tour began on November 18, 1998 and a land route to Mt. Kumgang also opened on September 1, 2002. These historical events have brought huge changes in the tourism industry of South and North Korea, and over 1,000 tourists are enjoying the Mt. Kumgang tour everyday. Nevertheless, the Mt. Kumgang International Tourism Zone is still poor in tourist accommodations as well as tourism infrastructure. Legal and institutional systems as an international tourism zone have not been established, and incidental and convenience facilities are insufficient. All these problems make it difficult to operate the special zone. Thus, this study set the following objectives to solve these problems: Establish systematic theories on the Mt. Kumgang International Tourism Zone, analyze theories on external factors, factors affecting tourist accommodation expansion, and use the findings as basic materials for tourist accommodation expansion strategies.

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Relationship between the Aboveground Vegetation Structure and Fine Roots of the Topsoil in the Burnt Forest Areas, Korea (산화적지에서 지상부 식생구조와 표토에 분포하는 세근의 관계)

  • Lee, Kyu-Song;Park, Sang-Deog
    • The Korean Journal of Ecology
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    • v.28 no.3
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    • pp.149-156
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    • 2005
  • This study was conducted to elucidate the relationship between the aboveground vegetation structure and fine roots of the topsoil (<15m), and thereafter to obtain the regression models for the estimation of the fine roots of the topsoil using the aboveground vegetation values in the burned forest areas, Korea. The FRT (fine roots of the top soil) as well as the aboveground vegetation structure showed spatial variation in the earlier successional stages after forest fire. The fine roots (<2 mm) of the topsoil in the earlier successional stages than the first 3 year after forest fire showed the range from 3 to 166 g $DM/m^2$. The FRT in the naturally regenerated sites and planted sites after forest fire was closely correlated with the vegetation indices, especially lvc, representing the development status of the aboveground vegetation. The FRT in the terrace seeding work sites after forest fire was closely correlated with year elapsed after terrace seeding work. The FRT in the terrace seeding work sites showed the much higher values because of the vigorous growth of grass species than the other sites. In the naturally regenerated sites, the FRT showed the parabola form according to the increment of aboveground vegetation value (Ivc). Although the aboveground vegetation value (Ivc) showed a tendency to increase logarithmically during the secondary succession after forest fire, the estimated fine roots of the topsoil was depicted the parabola form showing the gradual increment until the first 15 years and slight decrease thereafter. Decrease of FRT in the later successional stage showing the high vegetation value may be caused by increment of the woody species contribution to the vegetation value (Ivc). Our results represented that the aboveground vegetation value (Ivc) can be used to the estimation of the fine roots of the topsoil in burned forest areas.

Comparison of Three Kinds of Methods on Estimation of Forest Carbon Stocks Distribution Using National Forest Inventory DB and Forest Type Map (국가산림자원조사 DB와 임상도를 이용한 산림탄소저장량 공간분포 추정방법 비교)

  • Kim, Kyoung-Min;Roh, Young-Hee;Kim, Eun-Sook
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.4
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    • pp.69-85
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    • 2014
  • Carbon stocks of NFI plots can be accurately estimated using field survey information. However, an accurate estimation of carbon stocks in other unsurveyed sites is very difficult. In order to fill this gap, various spatial information can be used as an ancillary data. In South Korea, there is the 1:5,000 forest type map that was produced by digital air-photo interpretation and field survey. Because this map contains very detailed forest information, it can be used as the high-quality spatial data for estimating carbon stocks. In this study, we compared three upscaling methods based on the 1:5,000 forest type map and 5th national forest inventory data. Map algebra(method 1), RK(Regression Kriging)(method 2), and GWR(Geographically Weighted Regression)(method 3) were applied to estimate forest carbon stock in Chungcheong-nam Do and Daejeon metropolitan city. The range of carbon stocks from method 2(1.39~138.80 tonC/ha) and method 3(1.28~149.98 tonC/ha) were more similar to that of previous method(1.56~156.40 tonC/ha) than that of method 1(0.00~93.37 tonC/ha). This result shows that RK and GWR considering spatial autocorrelation can show spatial heterogeneity of carbon stocks. We carried out paired t-test for carbon stock data using 186 sample points to assess estimation accuracy. As a result, the average carbon stocks of method 2 and field survey method were not significantly different at p=0.05 using paired t-test. And the result of method 2 showed the lowest RMSE. Therefore regression kriging method is useful to consider spatial variations of carbon stocks distribution in rugged terrain and complex forest stand.

Ultrastructure of Blacktip Grouper, Epinephelus fasciatus Spermatozoa (홍바리, Epinephelus fasciatus 정자의 미세구조)

  • Kim, Seong-Hoon;Lee, Chi-Hoon;Song, Young-Bo;Ju, Hea-Sung;Kim, Hyung-Bae;Lee, Young-Don
    • Applied Microscopy
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    • v.42 no.2
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    • pp.61-66
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    • 2012
  • Ultrastructural characteristics of blacktip grouper, Epinephelus fasciatus spermatozoa were investigated using transmission and scanning electron microscopy. The spermatozoa of E. fasciatus consisted of a spherical head part, a midpiece with cytoplasmic canal entrance and a flagellum with lateral fins. Internal ultrastructurally, the nucleus contains high electron dense chromatin having granular particles and has no acrosome. The centriolar complex lies outside of the nuclear fossa and it is connected by the osmophilic filaments. Also the osmophilic filaments connect between the centriolar complex and the nuclear membrane. The midpiece contains eight to nine spherical mitochondria, cytoplasmic canal and necklaces. The flagellum has a typical 9+2 axonemal structure. The lateral fins contain vesicles and a typical 9+2 axonemal structure. Consequently this study contributes to comparative grouper spermatology and provide useful systematic taxonomic characters.

The Estimation of Gross Primary Productivity over North Korea Using MODIS FPAR and WRF Meteorological Data (MODIS 광합성유효복사흡수율과 WRF 기상자료를 이용한 북한지역의 총일차생산성 추정)

  • Do, Na-Young;Kang, Sin-Kyu;Myeong, Soo-Jeong;Chun, Tae-Hun;Lee, Ji-Hye;Lee, Chong-Bum
    • Korean Journal of Remote Sensing
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    • v.28 no.2
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    • pp.215-226
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    • 2012
  • NASA MODIS GPP provides a useful tool to monitor global terrestrial vegetation productivity. Two major problems of NASA GPP in regional applications are coarse spatial resolution ($1.25^{\circ}{\times}1^{\circ}$) of DAO meteorological data and cloud contamination of MODIS FPAR product. In this study, we improved the NASA GPP by using enhanced input data of high spatial resolution (3 km${\times}$3 km) WRF meteorological data and cloud-corrected FPAR over the North Korea. The improved GPP was utilized to investigate characteristics of GPP interannual variation and spatial patterns from 2000 to 2008. The GPP varied from 645 to 863 $gC\;m^{-2}\;y^{-1}$ in 2000 and 2008, respectively. Mixed forest showed the highest GPP (1,076 $gC\;m^{-2}\;y^{-1}$). Compared to NASA GPP (790 $gC\;m^{-2}\;y^{-1}$);FPAR enhancement increased GPP (861) but utilization of WRF data decreased GPP (710). Enhancements of both FPAR and meteorological input resulted in GPP increase (809) and the improvement was the greatest for mixed forest regions (+10.2%). The improved GPP showed better spatial heterogeneity reflecting local topography due to high resolution WRF data. It is remarkable that the improved and NASA GPPs showed distinctly different interannual variations with each other. Our study indicates improvement of NASA GPP by enhancing input variables is necessary to monitor region-scale terrestrial vegetation productivity.