• 제목/요약/키워드: water-level change

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춘천(春川)댐 방류시(放流時) 교량(橋梁)의 안정성(安定性) 검토(檢討)를 위한 수리모형실험(水理模型實驗) 연구(硏究) (Hydraulic Model Test for Bridge Stability Analysis at Downstream of Chun-Chon Dam)

  • 최한규;백효선;최상순
    • 산업기술연구
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    • 제24권B호
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    • pp.117-122
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    • 2004
  • In The case of the bridge which is located in the downstream of the dam, effect of the running water and stability of the bridge is studing by using the Hydraulic model test. 1. The water level change of 'Seosang1 bridge' along Chunchon dam spill occurred through this experiment more greatly than a numerical conspiracy. 2. Bight is the spot where a difference occurs in located bridge piers(p18-p28) greatly, and an influence of Chunchon dam occurs in greatly.

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CJ-50002(비브리오백신)의 랫드에 대한 4주간 경구 반복투여 독성연구 (Four-Week Oral Toxicity Study of CJ-50002 (Vibrio Vaccine) in Rats)

  • 윤병일;정수연;김달현;이영수;김대용
    • Toxicological Research
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    • 제15권1호
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    • pp.9-17
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    • 1999
  • This study was performed to evaluate the subacute toxicity of CJ-50002 (Vibrio Vaccine) in SPF Spraqur-Dawley (SD) rats. Vibrio vaccine was administered orally at a dose level of high (167mg/kg/day), medium (16.7mg/kg/day), and low (16.7mg/kg/day) once a day and repeated fro 4 weeks. Ten males and female rats were assigned to each group. After 4 week administration, no significant dose-dependent changes in body weight, water and food consumption rate or organ weight were noted dependent changes in body weight, water and food consumption rate or organ weight were noted among 4 groups. Urinanalysis, hematology, and serum chemistry, also fail to detect any dose-related change among 4 groups tested. During necropsy and histopathological examination, no specific toxicity related to treated material was found. The result of this study demonstrated that vibrio vaccine when administered orally for 4 weeks at a high dose of 167mg/kg/day, no dose-related toxicity was found in treated make and female rats.

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터널 건설에 따른 환경영향 평가 및 대응기술 개발 방향 (Overview of Environmental Impact Assessment and Environmental Protection Technology in Tunnel Construction)

  • 배규진
    • 한국터널공학회:학술대회논문집
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    • 한국터널공학회 2005년도 학술발표회 논문집
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    • pp.63-74
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    • 2005
  • The environmental influence in tunnel construction is the drying of the ground water, the drop of the ground water level, and noise and vibration by tunnel excavation. The environmental influence can cause the change of natural ecosystem and the source of popular complaints. In case of popular complaints, the tunnel construction can be stopped or the construction period can be extended. Also, the financial loss may be reached to hundreds of billions won. The technology development to minimize the environmental influence in the tunnel construction is very important in order to control popular complaints and to preserve ecosystem. It should be required the investigation, the evaluation, and the assessment of environmental impact to reduce environmental influence in the tunnel construction. The objective of this research is to review the environmental impact assessment in Korea and to introduce the environmental protection technology which minimizes the environmental influence generated in the tunnel construction.

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연료전지 수소 재순환 시스템의 유동해석 (Flow analysis of the Hydrogen Recirculation System for Fuel Cells)

  • 김재춘;이용택;정진택;김용찬;황인철
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2005년도 연구개발 발표회 논문집
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    • pp.759-764
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    • 2005
  • In this paper, numerical analysis of hydrogen recycle system has been conducted in order to enhance the efficiency of automotive fuel cell. Generally, the excess hydrogen is provided in the automotive fuel cell. Since the non-reaction hydrogen reduces automotive fuel cell efficiency, reuse of the non-reaction hydrogen can be helpful to improve the fuel cell performance. In case of PEM FC, the water vapor is provided to hydrogen from the cathode so that the mixture experiences phase change depending on the changes of pressure and temperature. The internal flow of the mixture in the hydrogen recirculation system of fuel cell was investigated for real flow conditions. The variation of performance, properties and mass fractions of mixture, hydrogen and water-vapor were investigated. This study was performed based on 80KW level automotive fuel cell's recycling system.

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A Study on the Sustainable Features of Realized and Planned Floating Buildings

  • Moon, Chang-Ho
    • 한국항해항만학회지
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    • 제36권2호
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    • pp.113-121
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    • 2012
  • According to the climate change and the improvement of income level, floating building on water has been emerging as a strong alternative. This study was intended to suggest some reference materials of sustainability for new floating building projects. The concept of sustainability and floating building was investigated, and 3 realized projects and 3 planned projects were reviewed in terms of sustainability. Sustainable features of the sample projects can be summarized as recycled and relocatable usage, adoption of various renewable energy techniques, installation of self-supporting plant, application of modular system and others like new material & open layout. Sustainable features need to be developed more and more in detail and applied to many types of floating buildings.

마우스 비장내 수은의 미세구조적 위치 (Ultrastructural Localization of Mercury in Spleen of the Mouse)

  • 조현욱;김명훈;이성태
    • Applied Microscopy
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    • 제28권4호
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    • pp.551-561
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    • 1998
  • The autometallographic method was used to demonstrate the localization of mercury deposits in spleen of mouse. The mercury deposits were identified with the light and electron mocroscope. Mice were treated with methylmercuric chloride in the drinking water (demineralized water) for 40 days. Control and mercury treated groups showed no significant differences in mean body weight and spleen weight per one mouse. Mercury grains were appeared in the germinal center of white pulp consist of a preponderancing lymphocytes, not in red pulp and capsule. At the ultrastructural level, mercury deposits were restricted to lysosomes of macrophage and lymphocyte. Specially, volume in lysosomes of the macrophage was increased. These results suggest that mercury localization in lysosomes is associated with the change of immune activity.

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천궁의 열수추출액이 고지방식이에 의한 흰쥐의 혈장 중 효소활성과 호르몬 및 간장의 지방축적에 미치는 영향 (Effect of Cnidi rhizoma Boiling Extract Solution on Enzyme and Hormone of Plasma, and Liver in the Fatted Rats Induced by High Fat Dietary)

  • 성태수;손규목
    • 한국식품영양학회지
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    • 제7권2호
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    • pp.108-113
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    • 1994
  • This study was carried out to evaluate the effect of Cnidi rhizoma (CR) water extract on fat accumulation In fatted rats induced by the oral high fat administration for six weeks. To accomplish this evaluation, the serum and liver tissue have been examined for enzyme activity, cortisol and insulin level. The change of liver or tissue have been observed by the light microscope. GOT GPT and LDH activities were lower than the control group. Insulin and cortisol were higher than the control group, due to the fat accumulation. The liver of the control group observed by the tight microscope appeared to the fatty liver, but CR group showed some improvement of the fatty liver Based on the above results, it was shown that it is possible to improve fat accumulation induced by high fat dietary through using the oral administration of Cnidi rhizoma water extract.

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An XPS Study of YBaCuO Compounds

  • Myung-Mo Sung;Yunsoo Kim
    • Bulletin of the Korean Chemical Society
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    • 제11권2호
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    • pp.118-123
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    • 1990
  • X-ray photoelectron spectra have been obtained and comparisons have been made for 1-2-3 and 2-1-1 phases of YBaCuO compounds. The photoelectron binding energies of all the constituent elements are consistently larger for the 2-1-1 phase than for the 1-2-3 phase. The peak intensities reflect different stoichiometries of the two phases. For the superconducting 1-2-3 phase, its degradation in air and interaction with water and carbon dioxide were examined by taking core level spectra of all the elements. It appears that yttrium is the most affected by exposure to air, since it undergoes a rapid change to carbonate when water and subsequently carbon dioxide are introduced.

공조설비의 필터차압 변화에 따른 에너지 소비성능 평가 (Evaluation of Energy Consumption of HVAC System for Air Filter Pressure Difference Change in Commercial Buildings)

  • 원근호;곽노열;허정호
    • 설비공학논문집
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    • 제16권12호
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    • pp.1227-1233
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    • 2004
  • Air handling unit (AHU)'s air filter pressure difference is important for energy consumption and indoor air quality. Both energy Performance data and air filter differential pressure of AHU in real office buildings were monitored and analyzed to investigate quantitatively energy impact as dust buildup level on air filter grows. We also modeled and simulated CAV system using HVACSIM+ program to examine the energy effect of dust buildup on filters. Through analysis of time series pressure drop data, the filter pressure difference rate has been increased due to cumulative supply air flow rate increase. As filter pressure drop increased to 1 inch water column, it is found that the supply air flow rate was decreased by 10%, the chilled water flow rate was increased by 5.9% and the pump energy consumption was increased to 5.9%.

클로라민 소독에 의한 THMs 생성에 관한 연구 (A Study the THMs Formation by Chloramination Disinfection)

  • 김평청;우달식;남상호
    • 환경위생공학
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    • 제14권1호
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    • pp.11-16
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    • 1999
  • This study was performed to investigate THMs formation by chloramination as a secondary disinfection in drinking water distribution system. As the $Cl_2/NH_3-N$ ratio increased from 1:1 to 4:1, the THMs concentration had actually no change in the breakpoint curve of pH 6, 7. At pH 8, THMs level was not augmented at between 1:1 and 5:1. In the $Cl_2/NH_3-N$ ratio of more than 5:1 and 6:1 respectively, THMs level was raised. Only the chloroform of THMs was insignificantly detected by both preformed chloramine and preammoniation applications, which was probably attributed to the stoichiometrically unstable equilibrium in the preparation of chloramine, whereas $CHCl_3$, $CHCl_2Br$ and $CHClBr_2$ of THMs were found in the application of free chlorine. However it turned out that the THMs levels by chloramine was incomparably inferior to that of free chlorine.

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