• 제목/요약/키워드: ground-water

검색결과 3,622건 처리시간 0.034초

여수연안 정치망 어장의 환경요인과 어황 변동에 관한 연구 (Environmental Factors and Catch Fluctuation of Set Net Grounds in the Coastal Waters of Yeosu)

  • 김동수
    • 수산해양기술연구
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    • 제29권2호
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    • pp.94-108
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    • 1993
  • In order to investigate the relation between the environmental properties and catch fluctuation of set net fishing ground located in the coastal waters of Yeosu, oceanographic observation and catches on the grounds were carried out from Jan. to Dec. in 1990 and 1992. The results obtained are summarized as follows; 1) Because of the surveyed area is a costal shallow water, the fishing ground was influenced largely by atmospheric phenomena such as air temperature. precipitation. etc. and so showed large variations in temperature and salinity yearly. The inner water flowed out mainly between Yeosu ad Namhe-do, and then through Kumo-do between Dolsan-do and Kumo-do. On the other hand, off shore water was supplied into the fishing ground from the vicinity of Sori-do and Yokchi-do. thus the fishing ground was occupied usually by various sources of water. 2) The water mass in the fishing ground were divided into the inner water(29.0~30.6$\textperthousand$) and the mixed water(31,7~32.2$\textperthousand$) and off shore water(32.3~32.8$\textperthousand$) accourding to the distribution of salinity from T-S diagram plotted all salinity data observed in 1990 and 1992. In summer the inner and mixing water which was formed by river flowed southerly and spread south-easterly in the vicinity of Kumo-do. The off shore water which supplied from the vicinity of Sori-do and Yokchi-do and inner water formed the thermal front and halo front in summer. 3) The fishes caught by the set net were arranged in the order of catch amounts as follows: Spanish mackerel>Horse mackerel >Hair tail>Common mackerel> Sardine> Anchovy. The Catches of anchovy and sardine were high in April to May and those of hair tail and horse mackerel in July to September, but spanish mackerel were caught during the whole period of fishing. When inner water and mixing water appeared respectively and inner water and mixing water speared together in the set net fishing ground, the set net showed a high catch.

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비만 마우스 간의 항산화시스템에 대한 바나듐 함유 제주지하수의 증강효과 (Consumption of Jeju Ground Water Containing Vanadium Components Enhances Hepatic Antioxidant Defense Systems in ob/ob Mice)

  • 김아름다슬;유호진;현진원
    • 생명과학회지
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    • 제22권1호
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    • pp.1-6
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    • 2012
  • 비만 마우스의 산화적 스트레스에 대해 바나듐 함유 제주 지하수에 대한 연구로서, 제주 지하수는 수도수 처리군보다 비만 마우스 간의 과산화 지질을 감소시켰으며, superoxide dismutase, catalase, 그리고 glutathione peroxidase의 단백질 발현 및 활성 그리고 환원형 glutathione 양을 증가 시켰다. 제주 지하수는 항산화 효소의 전사 인자인 erythroid transcription factor NF-E2 (Nrf2)의 인산화형 단백질 발현을 증가시켰다. 이로서 제주 지하수는 Nrf2의 활성화를 통하여 항산화 효소시스템을 증가시켰다.

고압분사주입공법에 의한 지반개량사례연구(II) -흙막이벽 배면지반보강 및 차수효과 (Case Studies on Ground Improvement by High Pressure Jet Grouting(II) Effect on the Ground Reinforcement and Cut off of Ground Water Behind Temporary Retaining Walls)

  • 윤중만;홍원표;정형용
    • 한국지반공학회지:지반
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    • 제12권5호
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    • pp.5-16
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    • 1996
  • 지하수위가 높고 느슨한 사질토지반에서 가설흙막이벽을 설치하여 지하굴착공사를 실시할 경우 굴착저면에서 보일링현상이 발생하여 굴착공사 뿐만 아니라 인접구조물에 상당한 피해를 주게 된다. 따라서 최근에는 흙막이벽 배면지반의 강도를 증대시키면서 동시에 흙막이벽의 차수효과를 높이기 위하여 고압분사주입공법을 실시하여 차수벽을 설치하는 보조공법인 널지 이용되고 있다. 고압분사주입공법에 의해 가설흙막이벽 배면지반에 시공된 지반개량체의 지반보강효과 및 차수효과를 검토하기 위하여 각종 실내시험 및 현장시험을 실시하였다. 시험결과 지반개량체는 지반조건과 시공방법에 따라 약간의 차이는 있으나 충분한 흙막이벽 배면지반의 보강 및 벽체의 강성보강 효과를 얻을 수 있는 것으로 나타났다. 한편 지반개량체의 투수계수는 원지반의 투수 계수보다 10-2~10-3cm/s정도 작아서 흙막이벽의 차수효과를 기대할 수 있는 것으로 나타났다.

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금호강유역(琴湖江流域) 지하수대(地下水帶)에 관한 연구(硏究) (Groundwater Resources of Gum-Ho River Basin)

  • 한정상
    • 자원환경지질
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    • 제11권3호
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    • pp.99-108
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    • 1978
  • The Gum-Ho river basin is one of the densely populated area having more than 35% of the total population and it was also well irrigated since earlier days in the Nackdong river basin. Most of the easily developed source of surface water are fully utilized, and at this moment the basin is at the stage that no more :surface water can be made available under the present rapid development of economic condition. Since surface water supplies from the basin have become more difficult to obtain, the ground water resources must be thoroughly investigated and utilized greatly hereafter. In economic ground of the basin what part could ground water play? In what quantities and, for what uses could it be put? The answer to these questions can be relatively simple;the ground water resources in the basin can be put at almost any desired use and almost anywhere in the basin The area of the basin is at about $2088km^2$ in the middle part of Nackdong river basin and it is located along the Seoul-Pusan express highway. The mean annual rainfall is about 974.7mm, most of which falls from June to September during the monsoon. Accumulated is appeared approximately after every 8 year's accumlated dry period with the duration of 5 years. The water bearing formation in the basin include unconsolidated alluvial deposits in Age of Quaternary, saprolite derived from weathered crystalline rocks, Gyongsang sedimentary formations of the period from late Jurassic to Cretaceouse, and igneouse rocks ranging of the Age from Mesozoic to Cenozoic. The most productive ground water reservoir in the basin is calcareous shale and sandstones of Gyongsang system, which occupies about 66% of the total area. The results of aquifer test on Gyongsang sedimentary formation show that average pumping capacity of a well drilled into the formation with drilling diameter and average depth of $8{\frac{1}{2}}$ inch and 136m is $738m^3/day$ and also average specific capacity of those well is estimated $77.8m^3/D/M$. Total amount of the ground water reserved in the basin is approximately estimated at 37 billion metric tons, being equivalent 18 years total precipitations, among which 7 billion metric tons of portable ground water can be easily utilized in depth of 200 meters.

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사대강유역의 지하수 (Ground water in the four major basins in Korea)

  • 최승일
    • 물과 미래
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    • 제12권1호
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    • pp.21-27
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    • 1979
  • Ground water stored in the alluvium and the rocks provides the vase flow of the streams and can be withdraw from wells and infiltration galleries. And it is also recharge naturallyby precipitation. The amount of ground water in the four major basins it is estimated to be about 137,000 million cubiv meters(Table1), while nationwide ground water storage to be about 232,000 million cubic meters. The estimation of storage volume has been made on the basis of assumed thickness of the saturated zone of the different rocks and assumed porosities of those rocks. The values of the porosity of alluvium and saprolite were assumed to be 25% and 40% respectivvely which are based on tests made of similar materials in Georgia, U.S. The volume of water in storage is believed to be a conservative estimate. Detailed geologic and hydrologic investigation should be made where and when water resources are needed.

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유역모형 구축을 위한 8일간격 유량측정자료의 일유량 확장 가능성 (The Possibility of Daily Flow Data Generation from 8-Day Intervals Measured Flow Data for Calibrating Watershed Model)

  • 김상단;강두기;김문수;신현석
    • 한국물환경학회지
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    • 제23권1호
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    • pp.64-71
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    • 2007
  • In this study daily flow data is constructed from 8-day intervals flow data which has been measured by Nakdong River Water Environmental Laboratory. TANK model is used to expand 8-day intervals flow data into daily flow data. Using the Sequential quadratic programing, TANK model is auto-calibrated with daily precipitation and 8-day interval flow data. Generated and measured daily surface flow, ground water flow data and ground water recharge are shown to be in a good agreement. From this result, it is thought that this method has the potential to provide daily flow data for calibrating an watershed model such as SWAT.

서울지역 약수터에 대한 시민 여론 조사 (Survey of Citizens Public Opinion for Natural Spring Water in Seoul)

  • 김광래;길혜경;이만호;엄석원;이재영
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제16권2호
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    • pp.1-5
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    • 2011
  • We surveyed the citizens opinion about springs in Seoul for two years from 2008 to 2009. It was found that spring water was mostly used by citizens older than 50, and that 29.5% of citizens used purified tap water as drinking water, 27.2% of them used boiled tap water, 21.1% of them used spring water, and 12.1% of them used bottled water. Citizens who store spring water more than a day are 76.7%. Although many citizens (70.3%) knew that water quality had been tested, 40% of them didn't care about checking the certificate of water quality analysis. Once recognized that the spring water was unfit for drinking exceeded standard of drinking water, 85% of citizens would rather not use the spring water.

그라우트 재료별 열응답 특성 및 열교환기 운전온도 변화 (Thermal Response Property of Grout Materials from In-situ Test and Temperature Variation of Ground Heat Exchanger)

  • 김갑득;이성주;윤여상
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2008년도 하계학술발표대회 논문집
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    • pp.769-775
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    • 2008
  • The objective of this report is to determine the difference of thermal response that grouted two different materials, and compare the simulation result of the length of total ground heat exchanger length that using the ground thermal conductivity. And also to know heat exchange variation of ground heat exchanger temperature that measured with various test depth. The result shows that the test hole grouted with water permeable material got better thermal response than grouted with water impermeable material. However, with consideration of ingnore for the initial 12 hour data, the test hole grouted with impermeable material has larger thermal conductivity than the other. By former thermal conductivity, simulated data by engineering program shows only 3.4% difference or less. This result shows that ground thermal conductivity is not the main variables for the design program of ground heat exchanger. At the cooling or heating mode, base on the depth of -150m, the ground heat exchanger has best temperature at $-90{\sim}-60m$ and than getting worse because of entering water heat exchanged with leaving water in the same hole.

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전기투석을 이용한 지하수 중의 질산성질소 제거 (The removal of Nitrate-nitrogen from ground water by electrodialysis)

  • 민지희;김한승
    • 상하수도학회지
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    • 제22권3호
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    • pp.307-314
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    • 2008
  • In this study, the effects of applied voltage, solution pH and coexistence of other ions such as sulfate ion (${SO_4}^{2-}$) and chloride ion ($Cl^-$) were investigated on the removal of nitrate-nitrogen ($NO_3{^-}-N$) from ground water by electrodialysis. The examined operating conditions were evaluated for optimizing the removal efficiency of $NO_3{^-}-N$. Real ground water samples taken from a rural area of Yongin city and artificial ones with components similar to the real ground water were tested for the study, which contained $NO_3{^-}-N$ concentration of 17mg/L that exceeds current drinking water quality standard of 10 mg/L. The increase in the removal rate of $NO_3{^-}-N$ was observed as the applied voltage increased from 5V to 30V, while no significant increase in the removal rate appeared at the applied voltage beyond 20V during a given operating time. The removal rate appeared to get lower at both acidic and basic condition, compared to neutral pH. Coexistence of of ${SO_4}^{2-}$and $Cl^-$ demanded much longer operating time to achieve a given removal rate or to meet a certain level of treated water concentration. When nitrate ion was combined with ${SO_4}^{2-}$and $Cl^-$, the removal rate was reduced by 4.29% and 10.83%, respectively.

Simultaneous Determination of 4-Nitrotoluene and Benzophenone in Ground Water and Soil by Gas Chromatography-Mass Spectroscopy

  • Kwon, Oh-Seung;Kim, Eun-Young;Ryu, Jae-Chun
    • 분석과학
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    • 제16권1호
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    • pp.59-69
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    • 2003
  • Benzophenone (BZP) and 4-nitrotoluene (4-NT) listed as endocrine disrupting chemicals are suspected to contaminate ground water sites and soil. Analytical method for simultaneous determination of the two chemicals in soil and ground water was developed by gas chromatography-mass spectrometry. Water (100 ml) was extracted with hexane, and soil (10 g) was extracted with methanol and hexane. Recovery in water was >72% for BZP and 90-118% for 4-NT. Recovery for 4-NT and BZP in soil was 51-59% with coefficient variation of less than 19.5%. Calibration curves showed a good linearity with $r^2=0.997$. In water and soil collected at nation-wide sites, BZP was found at 5 sites among 43 water sites at the concentration of $14.87{\pm}3.83ng/100 ml$. No 4-NT was found. It is suggested that this method is appropriate to the simultaneous quantitation of 4-NT and BZP in ground water and soil samples.