• Title/Summary/Keyword: Island stream

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Analysis of Thermal Characteristics for Areas of Musim Stream in Cheongju City (청주시 무심천 주변의 열환경 특성 분석)

  • Park, Jin-Ki;Na, Sang-Il;Park, Jong-Hwa
    • Korean Journal of Agricultural Science
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    • v.37 no.1
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    • pp.81-86
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    • 2010
  • The urban thermal environment can be an important index to detect heat island phenomena and manage it to improve urban life quality. Cheongju is a typical plain-city that main part has been formed and developed in lowland. The Mushim stream crosses the city from south to north. We reviewed the use of thermal remote sensing in stream around areas and the thermal environments, focusing primarily on the Urban Heat Island(UHI) effect. The purpose of this study is to determine the relationship between the stream nearby urban area and the stream cooling effect of UHI. The objectives are to determine the usefulness of KOMPSAT-2 bands MS3 and MS4 for vegetation cover mapping, and the usefulness of LANDSAT TM band 6 in identifying thermal environmental characteristics and UHI. Land Surface Temperatures (LST) are retrieved by single-channel algorithm to study the UHI from the 6th band (thermal infrared band) of LANDSAT TM images and thermal radiance thermometer based on remote sensing method and the LST distribution maps are accomplished according to the retrieval results. There is also comparison of satellite-derived and in situ measured temperature. The results indicated that the LST of urban center is higher than that of suburban area, the temperature of mountain and water are the lowest area, so it is clearly proved that there are obvious UHI effects by stream. The surface temperature distribution of Mushim stream is detected $2^{\circ}C$ lower than urban area.

Flood Discharge to Decision of Parameters in Han Stream Watershed (한천유역의 홍수량 산정을 위한 HEC-HMS 모형의 민감도 분석)

  • Jung, Woo-Yul;Yang, Sung-Kee;Kim, Dong-Su
    • Journal of Environmental Science International
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    • v.23 no.4
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    • pp.533-541
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    • 2014
  • The streams in Jeju Island have very distinctive hydrological and geological properties and there are a lot of limits in applying the general flood estimation method. This study presented parameters dominant in the Hancheon stream of Jeju Island by analyzing the sensitivity of parameters of HEC-HMS model regarding rainfall events in the target basin, and extracted the optimal parameter(Time of Concentration of Clark Unit Hydrograph: Kraven II method, Storage Coefficient: Sabol method) by analyzing and comparing it with the flood runoff data observed in the site and Jeju Island's observation data.

A Method of Simulating Ephemeral Stream Runoff Characteristics in Cheonmi-cheon Watershed, Jeju Island (제주 천미천 유역의 간헐하천 유출특성 모의 방안)

  • Kim, Nam-Won;Chung, Il-Moon;Na, Hanna
    • Journal of Environmental Science International
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    • v.22 no.5
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    • pp.523-531
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    • 2013
  • In this study, a method of simulating ephemeral stream runoff characteristics in Jeju watershed is newly suggested. The process based conceptual-physical scheme is established based on the SWAT-K and applied to Cheonmi-cheon watershed which shows the typical pattern of ephemeral stream runoff characteristics. For the proper simulation of this runoff, the intermediate flow and baseflow are controlled to make downward percolation should be dominant. The result showed that surface runoff simulated by using the modified scheme showed good agreement with observed runoff data. In addition, it was found that the estimated runoff directly affected the groundwater recharge rate. This conceptual model should be continuously progressed including rainfall interception, spatially estimated evapotranspiration and so forth for the reasonable simulation of the hydrologic characteristics in Jeju island.

Estimate of Roughness Coefficient for Stream at Island of Incheon (인천연안도서지역 소하천의 조도계수 산정(영흥도를 중심으로))

  • Choi, Gye-Woon;Chung, Yeoun-Jung;Han, Man-Shin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.935-940
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    • 2007
  • The roughness coefficients at stage gaging station were calculated and suggested based upon figures and formulae. The results shows that roughness coefficient decreases by increasing the discharge with the exception of no change or increasing in the cases having the tall vegetation and big influence from the stream bank. As a result of the research about the water quality in streams, vegetation and aquatic organisms, the paper suggests the need for management system to protect the organisms in danger of extinction and the need for preserving the diverse species at the estuary that is located in the downstream.

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Integrated Surface-groundwater Analysis in Jeju Island (제주 지역 지표수-지하수 연계 해석)

  • Kim, Nam-Won;Chung, II-Moon;Yoo, Sang-Yeon;Lee, Jeong-Woo;Yang, Sung-Kee
    • Journal of Environmental Science International
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    • v.18 no.9
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    • pp.1017-1026
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    • 2009
  • In Jeju island, the surface runoff characteristics are quite different from those of inland. Most of streams show dried characteristics by means of large portion of recharge which goes to the deep aquifer. For this reason, the accurate estimation of hydrologic components by using watershed model like SWAT is very difficult. On the other hand, the integrated SWAT-MODFLOW model is able to simulate the complex runoff structure including stream-aquifer interaction, spatial-temporal groundwater recharge and so on. The comprehensive results of Pyoseon region in Jeju island show that the amount of groundwater discharge to stream is very small, but it might be added to the discharge into the sea. Statistical analysis shows that SWAT-MODFLOW's results represent better than SWAT's. Also, SWAT-MODFLOW produces a reasonable water budget which shows a quite similar pattern of observed one. This result proves that the integrated SWAT-MODFLOW can be used as a proper tool for hydrologic analysis of entire Jeju island.

Estimate of Time of Concentration for Stream at Island near Coastal Region (연안도서지역 소하천 유역의 홍수도달시간 산정)

  • Chung, Yeoun-Jung;Choi, Gye-Woon;Han, Man-Shin;Shin, Sang-Man
    • Journal of the Korean Society of Hazard Mitigation
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    • v.7 no.5
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    • pp.151-158
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    • 2007
  • After installing calibrated depth scale at 11 different points inside the nine streams network for estimating time of concentration of stream in Young-Heung island near coastal region of Incheon we estimated the flow against actual rainfall events. By considering time of concentration formula which here mainly used for estimating the time of concentration from practical experiments, compared were three methods of inflow time and accepted to method of used the chart. The maximum flow occurrence time was estimated by an outflow model and observed maximum flow occurrence time were determined by to a comparative analysis. Kirpich formula was selected as the proper formula for calculating the concentration time inside the island streams. Kirpich formula could be applicable for the expanded range while catchment area of $0.453km^2$ and channel bed slope of $3{\sim}5%$ to catchment area of $2.0km^2$ and channel bed slope of about 1.5%.

MORPHOMETRIC ANALYSIS OF PLECOGLOSSUS ALTIVELIS OF CHEJU ISLAND AND THE NAKDONG RIVER (제주도 및 낙동강산 은어군의 형태 측정학적 분석)

  • Kim Eul-Bae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.3 no.4
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    • pp.228-232
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    • 1970
  • From the standpoint of fishery science it is an interesting matter to note that the size of Plecoglessus altivelis population on Cheju Island is smaller than that of the Nakdong River located in the southern part of Korea's mainland. Therefore the author carried out a comparative analysis to determine whether the populations differ because of racial or because of environmental conditions. The morphometric characters of the head length and the body length were used for the analysis of covariance and computed by a standard regression method of testing for the homogeneity of the populations. All samples were collected during 1968 and 1969 in the Milyang Stream of the Nakdong River and the Cheonji Stream of Cheju Island. The results of the analysis of the populations based on the significance test are as follows: 1. Since the F value observed was only 1.023 ($n_1=1,\;n_2=42$) the conclusion was reached that the samples could both belong to the same population. 2. In comparison with the deviations of the regression coefficients between the fish of the Nakdong River and Cherinji Stream, the populations were also highly significant suggesting that thelr belong to the same population. 3. The conclusion is that the fish of Cheju Island became a smaller fish in size due to an environmental condition but not due to racial characteristics.

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A Study of Urinary Incontinence and Lower Urinary Tract Symptoms of Women on an Island (도서지역 여성의 요실금 및 하부요로증상에 관한 연구)

  • Shin, Kyung-Rim;Park, Sun-Young
    • Korean Journal of Adult Nursing
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    • v.13 no.2
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    • pp.305-316
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    • 2001
  • The purpose of this study was to identify the frequency of Urinary Incontinence and lower urinary tract symptoms, to identify life style problems for UI of Women in anIsland. The sample consisted of 88 women in an island, a urinary symptom questionnaire developed by Jackson, et. al. and a demographic questionnaire were used to collect the data. The results of study were as following. 1. It was reported that the subjects have experienced UI and various lower urinary symptoms such as stress incontinence, nocturia, intermittency, abnormal stream, feeling of incomplete emptying and also they have experienced some degree of 'bother' 2. It was reported that the subjects have experienced various life style problems for UI 3. There was significant relationship between age and urgency (p=0.0262), bladder pain (p=0.0268), abnormal strength of stream (p=0.0074), inability to stop midstream (p=0.0026), and ability to perform daily tasks (p=0.0488), 4. There was a significant relationship between the number of discharges and urgency (p=0.0273), abnormal strength of stream (p=0.0307), and inability to stop midstream (p=0.0122). 5. There was a significant relationship between menopause and bladder pain (p=0.0020), abnormal strength of stream (p=0.0245), and inability to stop midstream (p=0.0002). 6. There was a significant relationship between the degree of experiences for lower urinary tract symptoms and life style behavior. Therefore, based on the results, a developing and carrying out of adequate UI care program is needed.

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Analysis and Comparison of Stream Discharge Measurements in Jeju Island Using Various Recent Monitoring Techniques (다양한 첨단 유량 계측기기를 활용한 제주도 하천 유출 비교 분석)

  • Yang, Sung-Kee;Kim, Dong-Su;Jung, Woo-Yul;Yu, Kwon-Kyu
    • Journal of Environmental Science International
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    • v.20 no.6
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    • pp.783-788
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    • 2011
  • Different from the main land of South Korea, Jeju Island has been in difficulties for measuring discharge. Due to high infiltration rate, most of streams in Jeju Island are usually in the dried state except six streams with the steady base flow, and the unique geological characteristics such as steep slope and short traveling distance of runoff have forced rainfall runoff usually to occur during very short period of time like one or two days. While discharge observations in Jeju Island have been conducted only for 16 sites with fixed electromagnetic surface velocimetry, effective analysis and validation of observed discharge data and operation of the monitoring sites still have been limited due to very few professions to maintain such jobs. This research is sponsored by Ministry of Land, Transport and Maritime Affairs to build water cycle monitoring and management system of Jeju Island. Specifically, the research focuses on optimizing discharge measurement techniques adjusted for Jeju Island, expanding the monitoring sites, and validating the existing discharge data. First of all, we attempted to conduct discharge measurements in streams with steady base flow, by utilizing various recent discharge monitoring techniques, such as ADCP, LSPIV, Magnetic Velocimetry, and Electromagnetic Wave Surface Velocimetry. ADCP has been known to be the most accurate in terms of discharge measurement compared with other techniques, thus that the discharge measurement taken by ADCP could be used as a benchmark data for validation of others. However, there are still concerns of using ADCP in flood seasons; thereby LSPIV would be able to be applied for replacing ADCP in such flooded situation in the stream. In addition, sort of practical approaches such as Magnetic Velocimetry, and Electromagnetic Wave Surface Velocimetry would also be validated, which usually measure velocity in the designated parts of stream and assume the measured velocity to be representative for whole cross-section or profile at any specified location. The result of the comparison and analysis will be used for correcting existing discharge measurement by Electromagnetic Wave Surface Velocimetry and finding the most optimized discharge techniques in the future.

Measurement and Analysis of Heat Island in summer in Gwangju (광주지역의 여름철 열섬현상 측정 및 분석)

  • Park, Seok-Bon
    • Journal of the Korean Solar Energy Society
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    • v.24 no.4
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    • pp.65-75
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    • 2004
  • This study aims to identify the degree of heat island in summer in Gwangju. For the purpose the city was classified according to use and surface components and temperature of the city for 24 hours was measured. The period of measurement was from August 11 to 13. 2003(two days). As a result of the measurement, the daily standard temperature of the central business areas and downtown areas was about $26^{\circ}C$. That of new residential areas neighboring the downtown was $25.1^{\circ}C$, and that of the outer residential areas was $23.4^{\circ}C$. In comparison with the result that temperatures of the Gwangju University playground and the Gwangju Weather Bureau were $23.1^{\circ}C$ and $23.3^{\circ}C$ respectively, the temperature of the downtown was about $2.7^{\circ}C$ Higher and that of the new residential area in downtown was about $1.8^{\circ}C$ higher. And it was demonstrated that the downtown outer road under Mt. Mudeung is a low-temperature zone. When temperature of the city was measured based on surface components, the daily standard temperature of Gwangju Stream Bok-gae area was the highest, $24.2^{\circ}C$, followed by $23.6^{\circ}C$ of the downtown stream and $22.2^{\circ}C$ of the greens (city park) and the waterside area.