• 제목/요약/키워드: end test

검색결과 3,039건 처리시간 0.024초

디지털 이미지 코릴레이션 기법으로 평가한 평면변형률 시험의 단부 구속 효과 (Restrained Effect of End Plate on Plane Strain Test Evaluated by Digital Image Correlation Method)

  • 장의룡;추윤식;이원택;정충기
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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    • pp.22-33
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    • 2008
  • The plane strain test has been used widely in order to examine the stress-strain relation and failure behavior. Its advantages are more realistic simulation of deformation and failure behaviors of soils. Most plane strain tests have been carried out with restrained end plates due to difficulties in manufacturing the equipment with free end condition and also performing it. In this study, plane strain tests with/without bottom plate restraint were performed on Jumunjin-sand. The measurement of overall and local deformation was accomplished by digital image correlation technique as well as external LVDT. By applying digital image correlation method using two consecutive images captured through the transparent wall, local deformation behavior of various parts inside the specimen was estimated. From digital image analysis result, the restrained effect of end plate was examined about formation and development of shear band, and deformation mechanism of sand under plane strain condition.

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암반에 근입된 현장타설말뚝의 선단지지거동 (End Bearing Behavior of Drilled Shafts in Rock)

  • 권오성;김경택;이영철;김명모
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.603-610
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    • 2005
  • The end bearing behavior of piles socketed in weathered/soft rock is generally dependent upon the mass conditions of rock with fractures rather than the strength of intact rock. However, there are few available data and little guidance in the prediction of the end bearing capacity of drilled shafts socketed in weathered/soft rock, considering rock mass weathering. Therefore, a database of 13 load tests was constructed first, and new empirical relationships between the base reaction modulus of piles in rock and rock mass properties were developed. No correlation was found between the compressive strengths of intact rock and the base reaction modulus of weathered/soft rock. The ground investigation data regarding the rock mass conditions(e.g. Em, Eur, RMR, RQD) was found to be highly correlated with the base reaction modulus, showing the coefficients of correlation greather than 0.7 in most cases. Additionally, the applicability of existing methods for the end bearing capacity of piles in rock was verified by comparison with the field test data.

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홀리스틱 교육방법을 통한 말기임종간호수업의 효과 (The Effects of Holistic Education on End-of-Life Care)

  • 성기월;조계화
    • 지역사회간호학회지
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    • 제19권4호
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    • pp.684-695
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    • 2008
  • Purpose: The purpose of this study was to evaluate changes regarding knowledge. attitude and practice toward end-of-life care in nursing university students. Method: This study adopted nonequivalent control group pretest-posttest design. The subjects consisted of 35 in the experimental group and 35 in the control group. The education was performed for 2 hours a session, once a week for 16 weeks. Data was analyzed by the SPSS/WIN 14 computer program, and included $X^2$ test. independent t-test. and repeated measure ANOVA. Results: There were statistically significant differences in knowledge toward end-of-life care between the experimental group and the control group. Conclusion: Findings suggested that holistic education on end-of-life care was effective to change students' knowledge toward end-of-life care. Therefore. holistic education is recommended as nursing education for nursing university students.

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1.8GHz 고주파 전단부의 결함 검사를 위한 새로운 BIST 회로 (A New Fault-Based Built-In Self-Test Scheme for 1.8GHz RF Front-End)

  • 류지열;노석호
    • 대한전자공학회논문지TC
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    • 제42권6호
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    • pp.1-8
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    • 2005
  • 본 논문에서는 1.8GHz 고주파 수신기 전단부의 결함 검사를 위한 새로운 저가의 BIST 회로(자체내부검사회로) 및 설계기술을 제안한다. 이 기술은 입력 임피던스 매칭 측정 방법을 이용한다. BIST 블록과 고주파 수신기의 전단부는 0.25m CMOS 기술을 이용하여 단일 칩 위에 설계되었다. 이 기술은 측정이 간단하고 비용이 저렴하며, BIST 회로가 차지하는 면적은 고주파 전단부가 차지하는 전체면적의 약 $10\%$에 불과하다.

Al-Li 합금 가공용 MQL 초경공구의 최적 형상에 관한 연구 (A Study on the Optimum Shape of MQL Carbide End-mill for Machining of Aluminum Lithium Alloy)

  • 이인수;김해지
    • 한국기계가공학회지
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    • 제12권6호
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    • pp.159-166
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    • 2013
  • In order to develop the optimum shape of an MQL carbide end-mill suitable for high speed machining of wing ribs which are a detailed part of larger wing structures, using a new material Al-Li alloy, a new MQL carbide end-mill is created that has various quantities of holes, hole sizes, and hole locations. A theoretical machining graph is generated using the hammer test and FRF simulation, and a machining test is performed in order to verify the machining stability in the high speed machining area. The optimum configuration of the MQL carbide end-mill is also presented through comparing the chattering, machining noise and cutting conditions, including the maximum cutting depth, rpm, and feed rate per teeth, for each cutter.

END금연동기유발 프로그램이 흡연고등학생의 일산화탄소, 금연 자기효능감, 흡연일수, 1일 흡연량에 미치는 효과 (The Effects of END Smoking Cessation Motivational Program on Carbon monoxide, Smoking Abstinence Self-efficiency, Smoking days and Daily smoking amount of Smoking High School Students)

  • 김은정;이혜경
    • 한국응용과학기술학회지
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    • 제38권3호
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    • pp.669-679
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    • 2021
  • 본 연구의 목적은 END 금연동기유발 프로그램이 흡연 고등학생의 일산화탄소, 금연자기효능감, 흡연일수, 1일 흡연량에 미치는 효과를 확인하기 위해 실시한 비동등성 대조군 전·후 시차설계를 이용한 유사 실험연구이다. 대상자는 C시에 소재한 고등학생으로 금연에 관심이 있는 흡연학생으로 실험군 27명, 대조군 28명 총 55명이었으며 자료수집은 2018년 7월 12일부터 10월 4일까지였다. 대상자에게 중재한 프로그램은 END 금연동기유발 프로그램으로 주 1회 50분, 총 6주간이었다. 중재결과 실험군은 대조군에 비해 금연 자기효능감(z=110.00, p<.001), 흡연일수(z=640.00, p<.001), 1일 흡연량(z=520.50, p<.016)이 지지되었다. 따라서 END 금연동기유발 프로그램은 학교 현장에서 흡연 고등학생의 흡연율을 낮추고 금연동기를 유발하여 금연을 유도하기 위한 중재로 본 프로그램의 적용을 제안한다.

노측 가드레일용 단부처리시설 성능평가기준 정립 및 개발 (A Study on Development & Establishment of Performance Evaluation Criteria for Guardrail End Treatments)

  • 주재웅;금기정;박제진;장대영
    • 한국도로학회논문집
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    • 제10권1호
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    • pp.123-134
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    • 2008
  • 국내에 설치되고 있는 가드레일의 단부처리시설(end treatments)은 차량의 관통이나 전복을 유발할 수 있는 형상을 하고 있어 사고 시 탑승자가치명상을 입을 가능성이 매우 높다. 실제로 차량이 가드레일의 단부에 충돌하였을 경우, 가드레일이 차량내부를 관통하여 탑승자에게 직접적인 상해를 입히는 경우가 발생되고 있다. 본 연구에서는 미국과 유럽의 성능평가기준(performance evaluation criteria)에 근거하여 국내 실정에 적합한 단부처리시설에 관한 성능평가기준(안)을 제시하였다. 또한 외국의 설치사례 및 연구사례를 조사하여 단부처리시설의 mechanism을 파악하고 국내 도로환경 에 적합한 단부처리시설을 제안하였다. LS-DYNA 프로그램을 이용한 컴퓨터 시뮬레이션을 통해 제안된 단부처 리시설에 대한 성능을 검증한 결과 성능평가기준(안)에 모두 만족한 결과를 보였으며, 개발 단부처리시설에 대한 실물차량 충돌시험을 수행한 결과 성능평가기준(안)의 탑승자 보호성능, 단부처리시설의 거동, 충돌 후 차량의 거동을 모두 만족하였다. 국내 최초로 탑승자의 안전을 고려하여 개발된 단부처리시설이 고속도로나 국도에 설치된다면 단부충돌사고의 심각성을 감소시켜 도로의 안전성을 향상시킬 수 있을 것으로 사료된다.

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Physical and numerical modeling of drag load development on a model end-bearing pile

  • Shen, R.F.;Leung, C.F.;Chow, Y.K.
    • Geomechanics and Engineering
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    • 제5권3호
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    • pp.195-221
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    • 2013
  • A centrifuge model study is carried out to investigate the behavior of pile subject to negative skin friction induced by pile installation, ground water drawdown and surcharge loading. A single end-bearing pile is examined as the induced negative skin friction would induce the most severe stress on the pile structural material as compared to friction piles. In addition, the behavior of the pile under simultaneous negative skin friction and dead/live loads is examined. To facilitate detailed interpretations of the test results, the model setup is extensively instrumented and involves elaborate test control schemes. To further examine the phenomenon of negative skin friction on an end-bearing pile, finite element analyses were conducted. The numerical analysis is first validated against the centrifuge test data and subsequently extended to examine the effects of pile slenderness ratio, surcharge intensity and pile-soil stiffness ratio on the degree of mobilization of negative skin friction induced on the pile. Finally experimental and numerical studies are conducted to examine the effect of applied transient live load on pile subject to negative skin friction.

Effects of Awareness of Good Death and End-of-Life Care Attitudes on End-of-Life Care Performance in Long-Term Care Hospital Nurses

  • Kim, Sun-Hee;Kim, Eun-Young
    • Journal of Hospice and Palliative Care
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    • 제24권1호
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    • pp.26-35
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    • 2021
  • Purpose: The purpose of this study was to determine the effects of awareness of good death and end-of-life care attitudes on end-of-life care performance in long-term care hospital nurses. Methods: This study used a cross-sectional study design. The participants were 147 nurses working at six long-term care hospitals with more than 200 beds in B city, South Korea. Data were collected using self-reported questionnaires, and analyzed with descriptive statistics, the t-test, analysis of variance, Pearson correlation coefficients, and multiple stepwise regression analysis using IBM/SPSS 26.0 for Windows. Results: The participants' awareness of good death, end-of-life care attitudes, and end-of-life care performance were positively correlated. The factors affecting end-of-life care performance were age, education level, awareness of good death, and end-of-life care attitudes; these variables explained 19.0% of end-of-life care performance. Conclusion: In order to improve long term care hospital nurses' end-of-life care performance, continuing education and training should be provided regarding awareness of good death and end-of-life care attitudes.

볼엔드밀 반구가공에서 가공 위치에 따른 절삭성 평가 (A Machinability test on the cutting position in the ball-end milling of hemisphere)

  • 박희범;김석원;이득우;김정석
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 춘계학술대회 논문집
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    • pp.890-893
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    • 2000
  • In this paper, the test of machinability according to the cutting positions when the ball end milling of hemispheric workpiece is carried out to find the optimum cutting position of free form surface die. Tool runout, cutting force. and chip form are measured. The results show that the optimum cutting condition to get the constant feed per tooth is the inclined angle of 40 degree of workpiece.

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