• Title/Summary/Keyword: Surface Area Index

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Relationship between Vegetation Index and Meteorological Element in Yongdam Catchment (용담댐시험유역 기상자료와 식생지수의 상관성 분석)

  • Lee, Hyeong-keun;Hwang, Ji-hyeong;Lee, Khil-Ha
    • Journal of Environmental Science International
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    • v.27 no.11
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    • pp.983-989
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    • 2018
  • The real-time monitoring of surface vegetation is essential for the management of droughts, vegetation growth, and water resources. The availability of land cover maps based on remotely collected data makes the monitoring of surface vegetation easier. The vegetation index in an area is likely to be proportional to meteorological elements there such as air temperature and precipitation. This study investigated relationship between vegetation index based on Moderate Resolution Image Spectroradiometer (MODIS) and ground-measured meteorological elements at the Yongdam catchment station. To do this, 16-day averaged data were used. It was found that the vegetation index is well correlated to air temperature but poorly correlated to precipitation. The study provides some intuition and guidelines for the study of the droughts and ecologies in the future.

Monitoring of the Drought in the Upstream Area of Soyang River, Inje-Gun, Kangwon-do Using KOMPSAT-2/3 Satellite (KOMPSAT-2/3 위성을 활용한 강원도 인제군 소양강 상류지역의 가뭄 모니터링)

  • Park, Sung-Jae;Lee, Chang-Wook
    • Korean Journal of Remote Sensing
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    • v.34 no.6_3
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    • pp.1319-1327
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    • 2018
  • Korea has a terrain vulnerable to drought due to the concentration of precipitation in summer and the large amount of groundwater discharge. Quantified drought indices are used to determine these droughts. Among these, drought index is mainly used for analysis of precipitation, and recently, researches have been conducted to monitor drought using satellite images. In this study, we used the KOMPSAT-2/3 image to calculate the water surface area and compare with the drought index in order to monitor the drought in the Upper Soyang River. As a result, it was confirmed that the tendency of the water surface area change and the trend of the drought index were similar in the satellite images. Future research could be used as a basis for judging drought.

Prediction of Land Surface Temperature by Land Cover Type in Urban Area (도시지역에서 토지피복 유형별 지표면 온도 예측 분석)

  • Kim, Geunhan
    • Korean Journal of Remote Sensing
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    • v.37 no.6_3
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    • pp.1975-1984
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    • 2021
  • Urban expansion results in raising the temperature in the city, which can cause social, economic and physical damage. In order to prevent the urban heat island and reduce the urban land surface temperature, it is important to quantify the cooling effect of the features of the urban space. Therefore, in order to understand the relationship between each object of land cover and the land surface temperature in Seoul, the land cover map was classified into 6 classes. And the correlation and multiple regression analysis between land surface temperature and the area of objects, perimeter/area, and normalized difference vegetation index was analyzed. As a result of the analysis, the normalized difference vegetation index showed a high correlation with the land surface temperature. Also, in multiple regression analysis, the normalized difference vegetation index exerted a higher influence on the land surface temperature prediction than other coefficients. However, the explanatory power of the derived models as a result of multiple regression analysis was low. In the future, if continuous monitoring is performed using high-resolution MIR Image from KOMPSAT-3A, it will be possible to improve the explanatory power of the model. By utilizing the relationship between such various land cover types considering vegetation vitality of green areas with that of land surface temperature within urban spaces for urban planning, it is expected to contribute in reducing the land surface temperature in urban spaces.

Analyzing Impact of the Effect of Greenbelts on the Land Surface Temperature in Seoul Metropolitan Area (수도권 그린벨트가 지표면 온도에 미치는 영향 분석)

  • Kim, Hee-Jae
    • Journal of Urban Science
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    • v.9 no.1
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    • pp.17-31
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    • 2020
  • This study aims to analyze the relations among greenbelt, urban land surface temperature empirically in order to assess the environmental effects of the greenbelt in the Seoul metropolitan area, objectively. For this purpose, this study conducts an empirical analysis of impacts of greenbelt on urban land surface temperature using a multiple-regression model. The main data employed in the analysis include real-time air pollution data, Landsat 8-OLI Landsat imagery data, KLIS data and Jip-gye-gu data. The major findings are summarized as follows. NDVI has a negative (-) correlation with the land surface temperature, and the urban temperature is high in areas with poor vegetation. The land surface temperature is low in residential or commercial areas, while the temperature is high in industrial areas. The temperature is low in green fields, open spaces, and river areas. it is found that the urban land surface temperature is low in the greenbelt zone. In the greenbelt zone, there is an effect that reduces the land surface temperature by 1% on average, as compared to that at the center of the Seoul metropolitan area. Especially, the center of the Seoul metropolitan area, in a range from 0.6% to 1.9% of the average temperature, the temperature gets lower up to approximately 3km from the greenbelt boundary.

Effect of Single or Fractionated X-Irradiation on the Pulmonary Surfactant in Rabbits (단회(單回) 및 분획(分劃) X선(線) 흉부(胸部) 조사(照射)가 가토(家兎) 폐포(肺胞) 표면활성(表面活性) 물질(物質)에 미치는 영향(影響))

  • Kim, Jun;Choo, Young-Eun
    • The Korean Journal of Physiology
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    • v.4 no.2
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    • pp.53-60
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    • 1970
  • In an attempt to clarity the effect of X-irradiation on the activity of surfactant in rabbits, and also to observe the possible difference when the irradiation was made in single or fractionated dose, X-ray in dose of 900 r was irradiated to rabbits either in single or fractionated dose of 300 r each day for three day, Tension-area diagram of lung extract was recorded automatically by a modified Langmuir-Wilhelmy balance with a synchronized recording system designed in this department. The surface tension of lung extract was measured at 1,3,5,24, and 48 hours post-irradiation, and the results were compared with the non-irradiated normal group. The result obtained are summerized as follows: 1) The maximal surface tension, minimal surface tension, width of the tension-area diagram at the surface area of 40% in lung extract, and stability index of the normal rabbit lung extracts were 40.73 dynes/cm, 8.96 dynes/cm. 20.71 dynes/cm, and 1.28 respectively. 2) Activity of surfactant was significantly depressed by X-irradiation, and the pattern of depression was more prominent in the single irradiation group than in the fractionated group. 3) It was found that the changes of the width of the tension-area diagram at the surface area of 40% in lung extract and stability indices corresponded well with that of the maximal or minimal surface tension.

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A Study on the Body Surface Area of Korean Women (Part I) Body Surface Area and It's Rational Rate (한국여성의 체표면적에 관한 연구(제1보) -체포면적 및 그의 안분비율에 대하여-)

  • Im Soon;Cha Ok Seon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.12 no.3 s.28
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    • pp.277-284
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    • 1988
  • The purpose of study was to measure to body Surface area and the rational rate of Korean adult's women. The subjects are 20 years old to 49 years old women (Their bust width ranges from 74.5 to 101.5 cm, the height from 144.6 to 163.3 cm, the weight from 44.2 to 74.0 kg, Rohrer Index from 1. 02 to 1. 89). As the experimental method, both the gypsum method, by which the shape of body can be copied as it is, and weighing method, from which planed body surface area can be measured with consistant thickness of polypropylene film used. The results were obtained as follows. 1. After dividing the Korean adult's women into four groups (single and married women in their twenties, those in their thirties, those in their fourties). The change of body surface area was reviewed in accordance with age groups. No great difference among age group was showed in whole body surface area. 2. average value of body surface area is 1, 514m^2 and the part of trunk shows the biggest difference to the age groups. 3. After dividing the middle of body into two groups, the relation of symmetry of each parts is reviewed with difference in body surface area. The results shows that the part of head & neck and lower limbs are symmetrical. The part of trunk and upper limbs are unsymmetrical. 4. Regional rates of each part of whole body surface area are follows. head $4.98\%$, each-lobes $0.46\%$, neck $2.01\%$, face$2.48\%$, upper trunk $19.64\%$, lower trunk $13.91\%$, upper armpits $1.76\%$, lower armpits $12.52\%$, hands $4.64\%$, thighs $18.89\%$, lower legs$13.10\%$, feet $6.01\%$.

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The Relationships Between Empirical Factors and Water Quality in Agricultural Reservoirs (농업용 저수지 수질과 경험적 인자들과의 관계)

  • Kim, Ho-Sub;Choi, Eun-Mi;Park, Ju-hyun;Hwang, Ha-Sun;Kim, Bomchul;Kong, Dong-Soo;Hwang, Soon-Jin
    • Journal of Korean Society on Water Environment
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    • v.24 no.3
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    • pp.333-339
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    • 2008
  • This study was carried out to assay the relationships between empirical factors and water quality in 23 agricultural reservoirs. Based on the trophic state index (TSI) deviation analysis, phosphorus in type II and III was the primary limiting factor on algal growth. BOD, COD, TP and chl.a concentration in type III reservoirs showed higher concentration than those of other types, while SS and TN concentration was no noticeable difference among three types. Characteristics of type III reservoirs showed large reservoir surface and drainage area, large surface area to volume (SAV) ratio, small drainage area to reservoir area (DA/RA) ratio, relatively old age, large paddy field and upland field to drainage area ratio (Mean 17.4%) and high generation and discharge loads compared to other types of reservoirs. In type I and II reservoirs, trends of BOD, TN, TP concentration in water column, were similar to those of the discharge load of pollutants. Although type II reservoirs generally showed low phosphorus discharge loads compared to type I reservoirs, TP and chl.a concentration in water column was greater than that of type I. Characteristics of type II reservoirs showed relatively large SAV ratio and old age compared to type I reservoirs and was similar to those of type III including eutrophic reservoirs.

The Evaluation of TOPLATS Land Surface Model Application for Forecasting Flash Flood in mountainous areas (산지돌발홍수 예측을 위한 TOPLATS 지표해석모델 적용성 평가)

  • Lee, Byong Jua;Choi, Su Mina;Yoon, Seong Sima;Choi, Young Jean
    • Journal of Korea Water Resources Association
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    • v.49 no.1
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    • pp.19-28
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    • 2016
  • The objective of this study is the generation of the gridded flash flood index using the gridded hydrologic components of TOPLATS land surface model and statistic flash flood index model. The accuracy of this method is also examined in this study. The study area is the national capital region of Korea, and 38 flash flood damages had occurred from 2009 to 2012. The spatio-temporal resolutions of land surface model are 1 h and 1 km, respectively. The gridded meteorological data are generated using the inverse distance weight method with automatic weather stations (AWSs) of Korea Meteorological Administration (KMA). The hydrological components (e.g., surface runoff, soil water contents, and water table depth) of cells corresponding to the positions of 38 flood damages reasonably respond to the cell based hourly rainfalls. Under the total rainfall condition, the gridded flash flood index shows 71% to 87% from 4 h to 6 h in the lead time based on the rescue request time and 42% to 52% of accuracy at 0 h which means that the time period of the lead time is in a limited rescue request time. From these results, it is known that the gridded flash flood index using the cell based hydrological components from land surface model and the statistic flash flood index model have a capability to predict flash flood in the mountainous area.

GENERATION OF AN IMPERVIOUS MAP BY APPLYING TASSELED-CAP ENHANCEMENT USING KOMPSAT-2 IMAGE

  • Koh, Chang-Hwan;Ha, Sung-Ryong
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.378-381
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    • 2008
  • The regulating and relaxing targets in the Land Use Regulation and Total Maximum Daily Loads are influenced by Land cover information. For the providing more accurate land information, this study attempted to generate an impervious surface map using KOMPSAT-2 image which a Korea manufactured high resolution satellite image. The classification progress of this study carried out by tasseled-cap spectral enhancement through each class extraction technique neither existing classification method. KOMPSAT-2 image of this study is enhanced by Soil Brightness Index(SBI), Green vegetation Index(GVI), None-Such wetness Index(NWI). Then ranges of extracted each index in enhanced image are determined. And then, Confidence Interval of classes was determined through the calculating Non-exceedance Probability. Spectral distributions of each class are changed according to changing of Control coefficient(${\alpha}$) at the calculated Non-exceedance Probability. Previously, Land cover classification map was generated based on established ranges of classes, and then, pervious and impervious surface was reclassified. Finally, impervious ratio of reclassified impervious surface map was calculated with blocks in the study area.

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The Relationship between the Dragonfly Diversity and the Environmental Factors in the Juam Wetland (주남습지에 서식하는 잠자리와 주변환경과의 관계)

  • Kim, Ji-Suk;Lee, Soo-Dong;Kim, Dong-Pil
    • Korean Journal of Environment and Ecology
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    • v.32 no.1
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    • pp.66-76
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    • 2018
  • This study surveyed the species and population of dragonflies in 20 study sites in the Junam wetland in May and July 2015 to investigate the relationship between the dragonflies and the inhabited environment. We measured the environmental factors such as the area of emergent plants, the area of floating and floating-leaved plants, the area of water surface, the area of water plants, and the nearby land-use type and analyzed the relationship to the dragonfly species, population, and diversity index. We found 757 dragonflies belonging to 21 species of 6 families. The area of floating and floating-leaved plants and the area of water surface affected the species diversity. The area of floating and floating-leaved plants and the area of surface water, in particular, showed the positive correlation with the species richness and the dominance value, respectively. The area of water surface showed the negative correlations with Shannon's diversity index and evenness. Among the type of surrounding land-uses, the dry fields and orchards showed significantly lower average species richness than wetlands. Among the species, Cercion calamorum and Crocothemis servilia were positively correlated with floating and floating-leaved plants. Cercion v-nigrum and Epophthalmia elegans were positively correlated with the area of water surface, and Ischnura asiatica and Ceriagrion nipponicum were negatively correlated. The recent uncontrolled proliferation of lotus colony in the Junam wetland is likely to affect greatly the species composition of dragonflies which have a close relationship with plant species.