• 제목/요약/키워드: Behavior of law

검색결과 996건 처리시간 0.024초

진동대 시험을 이용한 콘크리트 댐의 동적거동 특성 연구 (A Study on the Dynamic Behavior of Concrete Dam by Shaking Table Tests)

  • 황성춘
    • 한국소음진동공학회논문집
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    • 제15권7호
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    • pp.806-812
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    • 2005
  • This paper adresses the shaking table tests with 1/100 scaled model followed similitude law for OOdam main designing section to understand nonlinear behavior characteristics of concrete dam body by ground motion. As earthquake wave, Hachinohe and El Centre waves were used and acceleration and displacements are measured to analyze behaviors of dam body. For maximum ground acceleration range $(0.3\~0.9 g)$, the results showed linear behavior regardless of maximum 9round acceleration and secured safety of structure. To analyze the behavior of dam after tension cracking, 3 cm-notch was placed at the critical section of over-flowing section. As results of applying Hachinohe wave(0.8 g), Even though tension cracks were formed at over-flowing section by Hachinohe wave(0.8 g), it showed that the dam is stable for supporting upper stream Part of water tank of dam.

Ti-33.8wt% Al 금속간 화합물의 고온 산화거동 (High temperature oxidation behavior of Ti-33.8wt% Al intermetallic compounds)

  • 최송천;조현준;이동복
    • 한국표면공학회지
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    • 제26권5호
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    • pp.235-244
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    • 1993
  • The oxidation behavior of a two-phase(Ti3Al+TiAl) intermetallic compound, Ti-33.8wt%Al, has been in-vestigated in air at 800, 900 and $^1000{\circ}C$. Though the isothermal oxidation behavior followed a parabolic law up to 100$0^{\circ}C$ indicating that protective oxide scales were formed, the cyclic oxidation behavior followed a lin-ear law in the entire temperature range tested because flaky or stratified scales were usually spalled from the surface during cooling. During oxidation at 80$0^{\circ}C$, the alloy showed excellent oxidation resistance because continuous protective Al2O3 films were formed on the outermost surface of the alloy. However, above $900^{\circ}C$, the oxidation resistance of the alloy was decreased gradually because relatively non-protective TiO2 scales as well as some of Al2O3 scales were formed on the outer oxide scale. The oxidation mechanism of the alloy at different temperature was proposed.

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법학전문도서관 평가에 관한 연구 (A Study on the Evaluation of the Law School Libraries)

  • 김원만;이지연
    • 정보관리학회지
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    • 제27권1호
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    • pp.165-183
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    • 2010
  • 본 연구는 법학전문도서관이 제 역할과 기능을 할 수 있도록 실질적인 평가 내용을 다루어 법학전문도서관의 역할과 나아가야 할 방향을 제시하였다. 특히 법학전문도서관 사서들을 대상으로 그들의 의견을 수렴하여, 평가항목을 도출하였고, 법학전문도서관의 주 이용계층인 법학전문대학원 학생들을 대상으로 그들의 요구를 조사하고 분석하였다. 특히 독립적이고, 전문적으로 법학전문도서관을 위한 평가를 지향하였다는 점에서 그 의의를 찾을 수 있으며, 법학전문도서관의 건물과 시설 그리고 소장자료의 양과 함께 소장자료의 질, 법학도서관 사서의 기능과 역할 그리고 이용자의 만족도를 증진시키며, 외적인 면과 함께 법학전문도서관의 내실을 갖추는 것을 목적으로 하였다.

적층방법에 따른 복합적층판의 저속충격거동 조사 (Investigation of Low Velocity Impact Behavior of Laminated Composite Plates Considering the Stacking Method)

  • 김승덕;권숙준
    • 한국공간구조학회논문집
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    • 제10권4호
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    • pp.75-83
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    • 2010
  • 복합적층판은 다른 금속재료에 비해 높은 비강도, 비강성 등의 우수한 역학적 특성을 지니므로, 최근 다양한 분야에서 사용하고 있다. 그러나 이러한 복합적층판은 충격에 약하다는 단점이 있다. 그리하여 복합적층판의 충격거동에 대한 많은 연구가 이루어지고 있다. 충격거동을 조사하기 위해서는 우선 충격체와 복합적층판사이의 접촉력을 계산하여야 한다. 접촉력을 알기 위해서는 운동방정식, 복합적층판의 운동방정식 그리고 압입량에 관한 관계식을 동시에 풀어야 한다. 본 연구에서는 고전적인 헤르츠식, 썬식, 썬&양식 그리고 썬&탄식을 포함한 유한요소프로그램을 이용하여 복합적층판의 저속충격거동을 조사한다.

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Nylon 66의 무비례 하중에 대한 과응력 모델 (An Overstress Model for Non-proportional Loading of Nylon 66)

  • 호광수
    • 대한기계학회논문집A
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    • 제25권12호
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    • pp.2056-2061
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    • 2001
  • Non-proportional loading tests of Nylon 66 at room temperature exhibit path dependent behavior and plasticity-relaxation interactions. The uniaxial formulation of the viscoplasticity theory based on overstress (VBO), which has been used to reproduce the nonlinear strain rate sensitivity, relaxation, significant recovery and cyclic softening behaviors of Nylon 66, is extended to three-dimensions to predict the response in strain-controlled, comer-path tests. VBO consists of a flow law that is easily written for either the stress or the strain as the independent variable. The flow law depends on the overstress, the difference between the stress and the equilibrium stress that is a state variable in VBO. The evolution law of the equilibrium stress in turn contains two additional state variables, the kinematic stress and the isotropic stress. The simulations show that the constitutive model is competent at modeling the deformation behavior of Nylon 66 and other solid polymers.

시간 의존성 구성방정식을 이용한 AA6022-T4 판재의 탄성 복원 예측 (Time-Dependent Spring-back Prediction of Aluminum Alloy 6022-T4 Sheets Using Time-Dependent Constitutive law)

  • 박태준;류한선;이명규;정경환;;정관수
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 춘계학술대회 논문집
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    • pp.330-333
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    • 2009
  • The time-dependent constitutive law was developed based on viscoelastic-plasticity to describe the time-dependent spring-back behavior of aluminum alloy 6022-T4 sheets. Besides nonlinear viscoelasticity, non-quadratic anisotropic yield function, Yld2000-2d, was used to account for the anisotropic yield behavior, while the combined isotropic-kinematic hardening law was used to represent the Bauschinger effect and transient hardening. For verification purposes, finite element simulations were performed for the draw-bending and the results were compared with experimental results.

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시간 의존성 구성방정식을 이용한 AA6022-T4 판재의 탄성 복원 예측 (Time-Dependent Spring-back Prediction of Aluminum Alloy 6022-T4 Sheets Using Time-Dependent Constitutive law)

  • 박래준;류한선;이명규;정경환;;정관수
    • 소성∙가공
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    • 제18권6호
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    • pp.494-499
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    • 2009
  • The time-dependent constitutive law was utilized based on viscoelastic-plasticity to predict the time-dependent spring-back behavior of aluminum alloy 6022-T4 sheets. Besides nonlinear viscoelasticity, non-quadratic anisotropic yield function, Yld2000-2d, was used to account for the anisotropic yield behavior, while the combined isotropic-kinematic hardening law was used to represent the Bauschinger effect and transient hardening. For verification purposes, finite element simulations were performed for the draw-bending and the results were compared with experimental results.

의료과오사건에서 의사의 과실을 인정하기 위한 요건 - 대법원 2006. 10. 26. 선고 2004도486 판결 - (Requirements to accept the doctor's mistake in the medical malpractice case - Sentenced by October 26, 2006, by The Supreme Court, Precedent case no. 2004Do486 -)

  • 범경철
    • 의료법학
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    • 제8권1호
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    • pp.215-234
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    • 2007
  • The mission of the doctors is to take care of human life, body and health through the medical behaviors such as diagnosis and treatment. Under this job propensity, the doctors have care duty to take the best actions required to prevent the risk according to the patients' specific disease status. Such care duty of the doctor may be evaluated based on the medical behavior level at the medical institution and clinical medical study field. Such medical level should be understood in the normative level, considering the treatment environment, condition and specialty of the behavior, because it means the medical common sense known and acknowledged to the normal doctors. While the criminal suit requires the evidence for no doubt conviction, the civil suit requires more eased different standard. The results between the criminal and civil sentence may be different, because the confirmed former case may lead to long-term imprisonment and even death penalty, while the latter case puts only monetary penalty on the defeated party.

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Crack growth prediction and cohesive zone modeling of single crystal aluminum-a molecular dynamics study

  • Sutrakar, Vijay Kumar;Subramanya, N.;Mahapatra, D. Roy
    • Advances in nano research
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    • 제3권3호
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    • pp.143-168
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    • 2015
  • Initiation of crack and its growth simulation requires accurate model of traction - separation law. Accurate modeling of traction-separation law remains always a great challenge. Atomistic simulations based prediction has great potential in arriving at accurate traction-separation law. The present paper is aimed at establishing a method to address the above problem. A method for traction-separation law prediction via utilizing atomistic simulations data has been proposed. In this direction, firstly, a simpler approach of common neighbor analysis (CNA) for the prediction of crack growth has been proposed and results have been compared with previously used approach of threshold potential energy. Next, a scheme for prediction of crack speed has been demonstrated based on the stable crack growth criteria. Also, an algorithm has been proposed that utilizes a variable relaxation time period for the computation of crack growth, accurate stress behavior, and traction-separation atomistic law. An understanding has been established for the generation of smoother traction-separation law (including the effect of free surface) from a huge amount of raw atomistic data. A new curve fit has also been proposed for predicting traction-separation data generated from the molecular dynamics simulations. The proposed traction-separation law has also been compared with the polynomial and exponential model used earlier for the prediction of traction-separation law for the bulk materials.

Effects of Geometry and Operating Fluid on the Expansion Behavior of Liquid-Solid Fluidized Beds

  • Mohsen Mozafari-Shamsi;Alireza Malooze;Mohammad Sefid;Mostafa Soroor;Ehsan Mehrabi Gohari
    • Korean Chemical Engineering Research
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    • 제61권2호
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    • pp.312-321
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    • 2023
  • Fluidized beds have been widely used in industrial applications, which in most of them, the operating fluid is non-Newtonian. In this study, the combination of the lattice Boltzmann method (LBM) and the smoothed profile method has been developed for non-Newtonian power-law fluids. The validation of the obtained model were investigated by experimental correlations. This model has been used for numerical studying of changing the operating fluid and geometrical parameters on the expansion behavior in liquid-solid beds with both Newtonian and non-Newtonian fluids. Investigations were performed for seven different geometries, one Newtonian, and two non-Newtonian fluids. The power-law index was in the range of 0.8 to 1, and the results for the Newtonian fluidized beds show more porosity than the non-Newtonian ones. Furthermore, increasing the power-law index resulted in enhancing the bed porosity. On the other hand, bed porosity was decreased by increasing the initial bed height and the density of the solid particles. Finally, the porosity ratio in the bed was decreased by increasing the solid particle diameter.