• 제목/요약/키워드: Coupled Test

검색결과 834건 처리시간 0.025초

Unidirectional cyclic shearing of sands: Evaluation of three different constitutive models

  • Oscar H. Moreno-Torres;Cristhian Mendoza-Bolanos;Andres Salas-Montoya
    • Geomechanics and Engineering
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    • 제35권4호
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    • pp.449-464
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    • 2023
  • Advanced nonlinear effective stress constitutive models are started to be frequently used in one-dimensional (1D) and two-dimensional (2D) site response analysis for assessment of porewater generation and liquefaction potential in soft soil deposits. The emphasis of this research is on the assessment of the implementation of this category of models at the element stage. Initially, the performance of a coupled porewater pressure (PWP) and constitutive models were evaluated employing a catalogue of 40 unidirectional cyclic simple shear tests with a variety of relative densities between 35% and 80% and effective vertical stresses between 40 and 80 kPa. The authors evaluated three coupled constitutive models (PDMY02, PM4SAND and PDMY03) using cyclic direct simple shear tests and for decide input parameters used in the model, procedures are recommended. The ability of the coupled model to capture dilation as strength is valuable because the studied models reasonably capture the cyclic performance noted in the experiments and should be utilized to conduct effective stress-based 1D and 2D site response analysis. Sandy soils may become softer and liquefy during earthquakes as a result of pore-water pressure (PWP) development, which may have an impact on seismic design and site response. The tested constitutive models are mathematically coupled with a cyclic strain-based PWP generation model and can capture small-strain stiffness and large-strain shear strength. Results show that there are minor discrepancies between measured and computed excess PWP ratios, indicating that the tested constitutive models provide reasonable estimations of PWP increase during cyclic shear (ru) and the banana shape is reproduced in a proper way indicating that dilation and shear- strain behavior is well captured by the models.

ASCUS 환자에서 고위험 사람유두종바이러스 검사와 자궁경검사의 유용성 (The Usefulness of Concomitant High-Risk Human Papillomavirus Test and Colposcopy in Combination with the Papanicolaou Test in ASCUS Patients)

  • 김민경;손진희;김철환;최종상
    • 대한세포병리학회지
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    • 제16권1호
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    • pp.18-24
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    • 2005
  • The objective of this study was to ascertain whether or not the high-risk human papillomavirus (HPV) test, when coupled with Papanicolaou (Pap) smears, would prove useful in the screening and management of patients in whom abnormal Pap smear results had been obtained. Concomitant high-risk HPV detection using the hybrid capture II test and colposcopy with a Pap smear were performed with 176 patients, all of whom had been screened for both cervical carcinoma and precancerous lesions. We concomitantly performed colposcopies on these patients. Upon the follow-ups, the histologic diagnoses of these patients were confirmed via either biopsy or hysterectomy. The rate of high-risk HPV detection was correlated with cytologic diagnoses and colposcopic findings. The group composed of the high-risk HPV-positive ASCUS patients exhibited a 55.7% rate of cervical intraepithelial neoplasia (CIN), a significantly higher rate than the 7.5% result obtained in the high-risk HPV-negative ASCUS group. HPV test showed high sensitivity (87%) and low specificity (62.6%) in detection of CIN and colposcopy also showed high sensitivity (88%) and low specificity (22%). Any combination of these tests improve sensitivity, but not specificity. High-risk HPV tests, when coupled with Pap smears, constituted a useful triage approach with regard to colposcopy-directed biopsies in patients in whom a cytologic diagnosis of ASCUS had been rendered.

풍동실험을 통한 공동주택 지하주차장의 자연환기 성능 연구 (Experimental Study on Wind-driven Ventilation in Basement Parking Lots of Apartment)

  • 이시웅;노지웅
    • KIEAE Journal
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    • 제4권3호
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    • pp.103-107
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    • 2004
  • This paper aims for evaluating the wind-driven ventilation in basement parking lots of apartment. Wind tunnel tests coupled with tracer gas method were conducted, and classified by wind directions and opening types. The test results showed that, as for wind-driven ventilations, stack type openings were more successful than scuttle vent. Finally, according to Weibull distribution in Seoul, yearly averaged wind-driven ventilation rate was calculated.

철근콘크리트 부재의 장부작용에 관한 실험적 연구 (An Experimental Study on the Dowel Action in Reinforcement Concrete Members)

  • 박송철;신장호;김상식
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1993년도 가을 학술발표회 논문집
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    • pp.250-255
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    • 1993
  • This research is aimed at the experimental investigation of the characteristic contribution of the structural parameters, such as concrete over, concrete strength and reinforcing bar size on the dowel strength of the reinforced concrete stuctures. A total of twenty four specimens were tested for eight experimental conditions. The test results showed relatively close agreements with the values calculated by Vintzeleou-tassios equation. From the observations of the test results, it was found that the concrete cover affected almost linearly on the dowel strength , while the var size and the concrete strength showed coupled effects.

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일반공산비 기법을 이용한 INS/GPS 통합시스템의 고장 검출 및 격리 (Fault Detection and Isolation of Integrated Inertial/Satellite Navigation Systems Using the Generalized Likelihood Ratio Test)

  • 신정훈;임유철;유준
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.55-55
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    • 2000
  • This paper presents a fault detection and isolation(FDI) method based on Ceneralized Likelihood Ratio(GLR) test for the tightly coupled INS/GPS. State and measurement GLR tests detect INS or GPS fault. Once the fault is detected, Multi-hypothesized GLR scheme performs the fault isolation between INS and GPS and find which satellite malfunctions. Simulation results show that the GLR method is effective enough to detect and isolate a fault of the integrated navigation system.

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복합 처분환경 모사조건에서의 KURT 화강암의 역학적 물성 변화 평가 (Evaluation of mechanical properties of KURT granite under simulated coupled condition of a geological repository)

  • 박승훈;김진섭;김건영;권상기
    • 한국터널지하공간학회 논문집
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    • 제21권4호
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    • pp.501-518
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    • 2019
  • 심부 지하환경 조건에서 측정된 암석물성의 사용은 고준위폐기물처분장의 장기 안전성 평가 측면에서 해석의 신뢰성을 향상시킬 수 있다. 본 연구는 지하처분연구시설(Korea atomic energy research institute Underground Research Tunnel, KURT)의 화강암(한국원자력연구원, 대전)을 대상으로 고준위폐기물 처분장에서 예상되는 복합환경 조건을 구현한 후 암석의 역학적 물성 변화를 측정하였다. 실험은 심지층 처분환경이 모사되도록 열-수리-역학적 복합 환경(Thermo-Hydro-Mechanical, THM)이 조절될 수 있는 실험장치를 제작하였다. 다양한 복합 실험조건(M, HM, TM, THM)을 구현하여 일축압축강도와 간접인장강도, 탄성계수, 포와송비 등의 암석물성을 측정한 후 그 결과를 분석하였다. 실험결과, 처분장 근계암반 예상 온도범위 내에서는 KURT 화강암의 역학적 물성이 온도의 영향 보다 포화유무에 따른 변화가 더 큰 것을 확인할 수 있었다. 또한, 동일한 온도 조건에서 포화 유무에 따른 일축압축시험 결과는 최대 약 20%의 상대적인 차이를 보였으며, 간접인장시험 결과는 최대 13%의 차이가 발생하였다. 따라서 처분장의 장기거동에 따른 성능평가 및 안전성 예측을 위해서는 기존의 상온 실내시험을 통해 도출된 암석물성을 사용하기보다 심부 지하환경을 반영한 암석의 복합물성을 활용하는 것이 해석의 신뢰도 향상에 기여할 수 있을 것이다.

3D Packaging : Where All Technologies Come Together

  • 김영철
    • 한국마이크로전자및패키징학회:학술대회논문집
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    • 한국마이크로전자및패키징학회 2006년도 SMT/PCB 기술세미나
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    • pp.139-151
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    • 2006
  • [ $\bullet$ ] 3D is proliferating in all package types $\bullet$ Thin packages challenge all assembly technologies $\bullet$ Package assembly and test are closely coupled and design for testability is imperative to success

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