• 제목/요약/키워드: Shelby tube

검색결과 4건 처리시간 0.019초

전단파를 이용한 쉘비 튜브의 샘플 교란 효과 평가 (Assessing sample disturbance of shelby tube using shear waves)

  • 윤형구;이종섭;김준한;조용순
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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    • pp.134-141
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    • 2008
  • To evaluate the engineering properties of soil, the laboratory test always is carried out using samples obtained from the field. There are many studies to estimate the effect of sampling disturbance. The objective of this study appraises the disturbance using the shear wave velocity. The new shelby tube which three transducers are installed every 20cm interval is used. To laboratory tests, the large-scale consolidometer (calibration chamber) is used. During 1cm penetration, the shear wave velocity is measured by every transducer. The initial sampling disturbance is assessed through the velocity difference from bottom to right upside transducer. After finishing the sampling, the velocity is still measured every time to assess the soil disturbance in shelby tube itself. Through the measured velocity, the effect of disturbance is appraised. This study suggests that the sampling disturbance of shelby tube is effectively evaluated using shear wave velocity.

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인발시 시료이탈을 최소화한 불교란시료 채취 샘플러 개발 및 적용성 검토 (Development of a Sampler that Minimizes Sample Disturbance and Review of its Applicability)

  • 김종관;한진태;박가현;신휴성;장리;염선;김기석
    • 한국지반공학회논문집
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    • 제39권3호
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    • pp.17-27
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    • 2023
  • 지반의 특성을 정확하게 파악하기 위해서는 불교란시료 채취가 필수적이며, 이때 최대한 시료를 교란하지 않고 채취하는 것이 중요하다. 본 연구에서는 선단부에 시료 이탈을 방지하는 캐쳐를 장착하여 시료이탈을 최소화하는 샘플러를 개발하였고 이를 대상으로 현장시료채취, CT촬영, 실내시험을 통해 그 적용성을 검토하였다. 동일한 위치에서 쉘비튜브샘플러와 새롭게 개발한 샘플러로 채취한 시료의 CT촬영결과 쉘비튜브샘플러의 경우 수평방향 균열이 발생할 가능성이 높은데 반해 새롭게 개발한 샘플러의 경우 수평방향 균열의 발생을 억제할 수 있는 것으로 나타났다. 또한, 압밀시험과 전단시험 결과 새롭게 개발한 샘플러로 채취한 시료가 쉘비튜브샘플러로 채취한 시료에 비해서 최대전단강도가 높은 것으로 나타났다.

Evaluating the progenitor cells of ovarian cancer: analysis of current animal models

  • King, Shelby M.;Burdette, Joanna E.
    • BMB Reports
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    • 제44권7호
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    • pp.435-445
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    • 2011
  • Serous ovarian cancer is one of the most lethal gynecological malignancies. Progress on effective diagnostics and therapeutics for this disease are hampered by ambiguity as to the cellular origins of this histotype of ovarian cancer, as well as limited suitable animal models to analyze early stages of disease. In this report, we will review current animal models with respect to the two proposed progenitor cells for serous ovarian cancer, the ovarian surface epithelium and the fallopian tube epithelium.

세립토의 침식율 측정 (Measurements of Erosion Rate in Fine-Grained Soils)

  • 곽기석;정문경;정하익;우제윤;조삼덕
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.337-342
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    • 2002
  • A new apparatus called the EFA (Erosion Function Apparatus) has been built and tested to measure the erodibility of fine-grained soils. The EFA is a simple test to predict the erosion rate of fine-grained soils along with the corresponding velocity and shear stress. In addition, it is advantageous in predicting the scour rate for actual soil samples from bridge sites. The plot of erosion rate versus shear stress is the result of an EFA test. It Indicates the critical shear stress at which erosion starts and the rate of erosion beyond that shear stress. In order to measure the erodibilities of various soils, 14 Shelby Tube soil samples are collected from the actual bridge sites and tested using the EFA. The results of the EFA tests which are the relationships between erosion rates and shear stresses are presented in this paper and research continues to develop the correlation between the erosion function and the soil properties.

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