• 제목/요약/키워드: monotonic

검색결과 876건 처리시간 0.023초

1/10 축소 철근콘크리트보의 휨 거동에관한 실험적 연구 (An Experimental Study on the Flexural Behavior of 1/10-Scale Reinforced Concrete Beams)

  • 이한선;장신혁;김상규
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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    • pp.325-330
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    • 1995
  • Three types of model concrete with different mix ratios for 1/10 scale reinforced concrete model were made and tested to find the best solution for the simulation of mechanical characteristics of prototype concrete. Scaled reinforcing materials in diameter(D1.8) having similar con-figuration and mechanical properties with commercial deformed bars(D19) were prepared for 1/10 scale model tests of reinforced concrete structures. Two types of model test using D1.8 model reinforcing bars and model concrete, monotonic simple beam test and cyclic cantilever beam test, were performed to ensure and check the similitude of bond behavior between 1/10 scale model and prototype. The test results showed that the flexural behavior of 1/10 scale models can be simulated with accuracy enough for practical use in monotonic and cyclic loading test.

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Hardware-Aware Rate Monotonic Scheduling Algorithm for Embedded Multimedia Systems

  • Park, Jae-Beom;Yoo, Joon-Hyuk
    • ETRI Journal
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    • 제32권5호
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    • pp.657-664
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    • 2010
  • Many embedded multimedia systems employ special hardware blocks to co-process with the main processor. Even though an efficient handling of such hardware blocks is critical on the overall performance of real-time multimedia systems, traditional real-time scheduling techniques cannot afford to guarantee a high quality of multimedia playbacks with neither delay nor jerking. This paper presents a hardware-aware rate monotonic scheduling (HA-RMS) algorithm to manage hardware tasks efficiently and handle special hardware blocks in the embedded multimedia system. The HA-RMS prioritizes the hardware tasks over software tasks not only to increase the hardware utilization of the system but also to reduce the output jitter of multimedia applications, which results in reducing the overall response time.

Slenderness effects on the simulated response of longitudinal reinforcement in monotonic compression

  • Gil-Martin, Luisa Maria;Hernandez-Montes, Enrique;Aschheim, Mark;Pantazopoulou, Stavroula J.
    • Structural Engineering and Mechanics
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    • 제23권4호
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    • pp.369-386
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    • 2006
  • The influence of reinforcement buckling on the flexural response of reinforced concrete members is studied. The stress-strain response of compression reinforcement is determined computationally using a large-strain finite element model for bars of varied diameter, length, and initial eccentricity, and a mathematical expression is fitted to the simulation results. This relationship is used to represent the response of bars in compression in a moment-curvature analysis of a reinforced concrete cross section. The compression bar may carry more or less force than a tension bar at a corresponding strain, depending on the relative influence of Poisson effects and bar slenderness. Several cross-section analyses indicate that, for the distances between stirrups prescribed in modern concrete codes, the influence of inelastic buckling of the longitudinal reinforcement on the monotonic moment capacity is very small and can be neglected in many circumstances.

현장끼움벽으로 보강된 철근콘크리트 골조의 비선형 유한요소해석 (A Nonlinear Finite Element Analysis to Reinforced Concrete Frame Retrofitted with Cast-In Plate Infilled Shear Wall)

  • 한민기;이혜연;김선우;이갑원;최창식;윤현도
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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    • pp.73-76
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    • 2005
  • This paper discussed finite element method(FEM) models of the reinforced concrete frame retrofitted with cast-in plate infilled shear wall and analysed under constant axial and monotonic lateral load using ABAQUS. Detailed finite element models are created by studying the monotonic load response of the designed connection of reinforced concrete frame and cast-in plate infilled shear wall. The developed models account for the effect of material inelasticity, concrete cracking, geometric nonlinearity and bond-slip of steel, frame and infilled shear wall. In order to verify the proposed FEM, this study behaved analysis considered a diagonal reinforced steel. The analytical results compared with the experimental results.

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지수화 지수 커버리지 함수를 고려한 ENHPP 소프트웨어 신뢰성장 모형에 관한 연구 (A Study on ENHPP Software Reliability Growth Model based on Exponentiated Exponential Coverage Function)

  • 김희철
    • 정보학연구
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    • 제10권2호
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    • pp.47-64
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    • 2007
  • Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. Accurate predictions of software release times, and estimation of the reliability and availability of a software product require quantification of a critical element of the software testing process : test coverage. This model called enhanced non-homogeneous poission process(ENHPP). In this paper, exponential coverage and S-coverage model was reviewed, proposes the exponentiated exponential coverage reliability model, which maked out efficiency substituted for gamma and Weibull model(2 parameter shape illustrated by Gupta and Kundu(2001). In this analysis of software failure data, algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE statistics for the sake of efficient model, was employed.

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순수 비틀림 하중하에서 열화를 고려한 2상 스데인리스강의 저주기 피로특성 (Low Cycle Fatigue Characteristics of Duplex Stainless Steel with Degradation under Pure Torsional Load)

  • 권재도;박중철
    • 대한기계학회논문집A
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    • 제26권9호
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    • pp.1897-1904
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    • 2002
  • Monotonic torsional and pure torsional low cycle fatigue(LCF) test with artificial degradation were performed on duplex stainless steel(CF8M). CF8M is used in pipes and valves in nuclear reactor coolant system. It was aged at 430$^{\circ}C$ for 3600hrs. Through the monotonic and LCF test, it is found that mechanical properties(i.e., yield strength, strain hardening exponent, strength coefficient etc.) increase and fatigue life(N$\sub$f/) decreases with degradation of material. The relationship between shear strain amplitude(${\gamma}$$\sub$a/)and N$\sub$f/ was proposed.

감육배관의 파괴거동 평가 (Fracture Behavior Evalustion of Pipes with Local Wall Thinning)

  • 안석환;남기우;김선진;김현수;김진환;도재윤
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 추계학술대회논문집A
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    • pp.61-66
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    • 2001
  • Fracture behaviors of pipes with local wall thinning is very important for the integrity of nuclear power plant. In pipes of energy plants, sometimes, the local wall thinning may result from severe drosion-corrosion damage. However, effect of local wall thinning on strength and fracture behaviors of piping system were not well studied. In this paper, the monotonic bending tests were performed of full-scale carbon steel pipes with local wall thinning. A monotonic bending load was applied to straight pipe specimens by four-point loading at ambient temperature without internal pressure. From the tests, fracture behaviors and fracture strength of locally thinned pipe were manifested systematically. The observed failure modes were divided into four types; ovalization, ovalization+cracking, local buckling and local buckling+cracking. Also, maximum load was successfully evaluated.

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감육을 가지는 배관 용접부의 파괴거동 (Fracture Behavior of Welded Pipes with Local Wall Thinning)

  • 안석환;남기우;정정환;김용운
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.90-95
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    • 2003
  • Fracture behaviors of pipes with local wall thinning are very important for the integrity of nuclear power plant. In pipes of energy plants, sometimes, the local wall thinning may result from severe erosion-corrosion (E/C) damage. However, the effects of local wall thinning on strength and fracture behaviors of piping system were not well studied. In this paper, the monotonic bending tests were performed of full-scale welded and unwelded carbon steel pipes with local wall thinning. A monotonic bending load was applied to straight pipe specimens by four-point loading at ambient temperature without internal pressure. The observed failure modes were divided into four types; ovalization, crack initiation/growth after ovalization, local buckling and crack initiation/growth after local buckling. Also, the strengths of welded and unwelded piping system with local wall thinning were evaluated.

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Analysis of rigid and semi-rigid steel-concrete composite joints under monotonic loading - Part II: Parametric study and comparison with the Eurocode 4 proposal

  • Amadio, C.;Fragiacomo, M.
    • Steel and Composite Structures
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    • 제3권5호
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    • pp.371-382
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    • 2003
  • This paper analyses the response of rigid and semi-rigid steel-concrete composite joints under monotonic loading. The influence of some important parameters, such as the presence of column web stiffening and the mechanical properties of component materials, is investigated by using a three-dimensional finite element modelling based on the Abaqus code. Numerical and experimental responses of different types of composite joints are also compared with the analytical results obtained using the component approach proposed by Eurocode 4. The results obtained with this approach generally fit well with the numerical and experimental values in terms of strength. Conversely, some significant limits arise when evaluating initial stiffness and non-linear behaviour of the composite joint.

Analysis of rigid and semi-rigid steel-concrete composite joints under monotonic loading - Part I: Finite element modelling and validation

  • Amadio, C.;Fragiacomo, M.
    • Steel and Composite Structures
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    • 제3권5호
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    • pp.349-369
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    • 2003
  • The paper concerns the modelling of rigid and semi-rigid steel-concrete composite joints under monotonic loading through use of the Abaqus program, a widespread finite element code. By comparing numerical and experimental results obtained on cruciform tests, it is shown that the proposed modelling allows a good fit of the global joint response in terms of moment-rotation law. Even the local response in terms of stresses and strains is adequately predicted. Hence, this numerical approach may represent a useful tool for attaining a better understanding of experimental results. It may also be used to perform parametric analyses and to calibrate simplified mechanical models for practical applications.