• Title/Summary/Keyword: 사태 물질

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A Study on Transportation Characteristics of Debris dependent on Geologic Conditions (지질조건에 따른 사태물질 이동특성 고찰)

  • Chae Byung-Gon;Kim Won-Young;Lee Choon-Oh;Kim Kyeong-Su;Cho Yong-Chan;Song Young-Suk
    • The Journal of Engineering Geology
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    • v.15 no.2 s.42
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    • pp.185-199
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    • 2005
  • Properties of sliding materials are dependent on the lithology because debris is the product of rock weathering processes. In order to characterize transportation behavior of debris dependent of debris types, this study selected 26 debris flows over three areas composed with different rock weathering types and topographic conditions. Analyses of lithology, weathering, and topographic characteristics were performed by detailed field survey. Based on the field survey data, transportation behavior of debris was studied at the aspect of the relationship of grain size and volume of debris as well as topographic conditions. According to the study results, change of slope angle is very influential factor on runout distance of debris among the topographic factors. Because the sliding velocity and the energy of debris are frequently changed and more irregular on an undulating slope, the unout distance of debris is larger than that of an uniformly dipping slope. Runout distance of debris is also influenced by volume and grain size of debris. Volume of debris in the gabbro is four or five times larger than that of the granite area because it is controlled by the lithology. Considered with grain size distribution, runout distance of debris is longer in the gabbro area which is composed with irregular grain size bearing large corestones than that in the medium grained granite area.

A Test for Characterization on Landslides Triggering and Flow Features of Debris using a Flume test Equipment (모형실험 장치를 이용한 산사태 발생 및 사태물질 거동특성 실험)

  • Chae Byung-Gon;Song Young-Suk;Seo Yong-Seok;Cho Yong-Chan;Kim Won-Young
    • The Journal of Engineering Geology
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    • v.16 no.3 s.49
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    • pp.275-282
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    • 2006
  • This study was conducted laboratory flume tests to identify landslide features and flow characteristics of debris using a flume test equipment. Under the several test conditions dependent on rainfall intensity and slope angle, the authors measured pore water pressure, slope failure and displacement, spreading area of debris on a regular time interval. The test processes were also recorded by video cameras and digital still cameras. According to the test results, pore water pressures have trends of direct proportion to the rainfall intensity and the slope angle, resulting in high potential of landslide triggering. The spreading area of debris is also increased with the slope angle and the rainfall intensity as well as the rainfall duration.

항생물질 사용은 인체에 무해한 범위내에서

  • Song, Chul
    • The Microorganisms and Industry
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    • v.10 no.1
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    • pp.7-9
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    • 1978
  • 계란을 비롯하여 모든 축산식품중에서 잔류항생물질이 문제가 되고 있는 것은 비단 우리나라 만은 아닌 것이므로 새삼스럽게 큰 사회 문제로 파문을 일으킬 것은 없지만 사태의 중요성에 대하여는 진지하게 관심을 갖어야 한다. 그러한 이유중의 하나로 최근에 나타난 중요한 사태는 양계및 양축의 양적인 수의 증가는 사료의 소비량의 증가와 비례하지만 사료에 첨가하는 항생물질의 소비량은 해마다 몇번씩 이례적으로 증가하고 있는 사실이다. 그러므로 국민의 보건과 밀접한 관계가 있는 양계업에 종사하는 여러분을 위해서 이 기회에 알아 두어야 할 몇가지를 간략하게 소개하고저 한다.

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Assessment of Runout Distance of Debris using the Artificial Neural Network (인공신경망을 이용한 사태물질 이동거리 산정)

  • Seo Yong-Seok;Chae Byung-Gon;Kim Won-Young;Song Young-Suk
    • The Journal of Engineering Geology
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    • v.15 no.2 s.42
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    • pp.145-154
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    • 2005
  • This study conducted to develop an assessment method of runout distance of debris flow that is a major type of landslides in Korea. In order to accomplish the objectives, this study performed detailed field survey of runout distance and laboratory soil tests using 24 landslides over three pilot sites. Based on the data of the field survey and the laboratory tests, an assessment method of runout distance was suggested using the artificial neural network. The input data for the analysis of artificial neural network are change rate of slope angle, Permeability coefficient of in-situ soil, dry density, void ratio, volume of debris and the measured runout distance. The analyzed results using the artificial neural network show low error rate of inference distributing lower than $10\%$. Some cases have $5\%$ and $2\%$ of error rates of inferences. The results can be thought as excellent teaming rates. However, it is difficult to be accepted as excellent results if it is considered with the results derived using only 24 landslide data. Therefore, more landslide data should be surveyed and analyzed to increase the confidence in the assessment results.

Slope stability analysis and landslide hazard assessment in tunnel portal area (터널 갱구지역 사면안정성 및 산사태 위험도 평가)

  • Jeong, Hae-Geun;Seo, Yong-Seok
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.15 no.4
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    • pp.387-400
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    • 2013
  • In this study, the slope stability analysis and the landslide hazard assessment in tunnel portal slope were carried out. First, we selected highly vulnerable areas to slope failure using the slope stability analysis and analyzed the slope failure scale. According to analyses results, high vulnerable area to slope failure is located at 485~495 m above sea level. The slope is stable in a dry condition, while it becomes unstable in rainfall condition. The analysis results of slope failure scale show that the depth of slope failure is maximum 2.1 m and the length of slope failure is 18.6 m toward the dip direction of slope. Second, we developed a 3-D simulation program to analyze characteristics of runout behavior of debris flow. The developed program was applied to highly vulnerable areas to slope failure. The result of 3-D simulation shows that debris flow moves toward the central part of the valley with the movement direction of landslide from the upper part to the lower part of the slope. 3-D simulation shows that debris flow moves down to the bottom of mountain slope with a speed of 7.74 m/s and may make damage to the tunnel portal directly after 10 seconds from slope failure.

실시간 피폭해석 시스템 검증을 위한 야외 확산실험

  • 한문희;김은한;서경석;황원태
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05d
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    • pp.71-74
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    • 1996
  • 원자력시설의 비상사태시 대기중으로 방출된 방사성 물질로부터 주변 주민 및 환경이 받는 영향을 신속·정확하게 평가하고 그 피해를 최소화하기 위해 실시간 방사선 피폭해석 시스템을 개발하였다. 수립된 대기 확산모델의 검증 및 정확도 향상을 위하여 야외 확산실험이 수행되었다. 대기 확산모델의 계산결과와 실험을 통하여 관측된 추적자 가스의 농도 분포를 상호 비교한 바 어느 정도 일치하고 있었다. 그러나 일부 경우에서는 관측된 농도값과 계산된 농도값이 차이를 보이고 있는데, 이는 실험 대상 지역에서 충분한 기상 관측을 수행하지 못하여 시간에 따른 풍속의 변화를 확산모델에 자세히 반영하지 못하였기 때문이었다.

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