• Title/Summary/Keyword: Linear behavior

Search Result 2,505, Processing Time 0.03 seconds

Seismic analysis of tunnel considering the strain-dependent shear modulus and damping ratio of a Jointed rock mass (절리암반의 변형률 의존적 전단탄성계수 및 감쇠비 특성을 고려한 터널의 내진 해석)

  • Song, Ki-Il;Jung, Sung-Hoon;Cho, Gye-Chun;Lee, Jeong-Hark
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.12 no.4
    • /
    • pp.295-306
    • /
    • 2010
  • Contrary to an intact rock, the jointed rock mass shows strain-dependent deformation characteristics (elastic modulus and damping ratio). The maximum elastic modulus of a rock mass can be obtained from an elastic wave-based exploration in a small strain level and applied to seismic analyses. However, the assessment and application of the non-linear characteristics of rock masses in a small to medium strain level ($10^{-4}{\sim}0.5%$) have not been carried out yet. A non-linear dynamic analysis module is newly developed for FLAC3D to simulate strain-dependent shear modulus degradation and damping ratio amplification characteristics. The developed module is verified by analyzing the change of the Ricker wave propagation. Strain-dependent non-linear characteristics are obtained from disks of cored samples using a rock mass dynamic testing apparatus which can evaluate wave propagation characteristics in a jointed rock column. Using the experimental results and the developed non-linear dynamic module, seismic analyses are performed for the intersection of a shaft and an inclined tunnel. The numerical results show that vertical and horizontal displacements of non-linear analyses are larger than those of linear analyses. Also, non-linear analyses induce bigger bending compressive stresses acting on the lining. The bending compressive stress concentrates at the intersection part. The fundamental understanding of a strain-dependent jointed rock mass behavior is achieved in this study and the analytical procedure suggested can be effectively applied to field designs and analyses.

Nonlinear vibration analysis of laminated plates resting on nonlinear two-parameters elastic foundations

  • Akgoz, Bekir;Civalek, Omer
    • Steel and Composite Structures
    • /
    • v.11 no.5
    • /
    • pp.403-421
    • /
    • 2011
  • In the present manuscript, geometrically nonlinear free vibration analysis of thin laminated plates resting on non-linear elastic foundations is investigated. Winkler-Pasternak type foundation model is used. Governing equations of motions are obtained using the von Karman type nonlinear theory. The method of discrete singular convolution is used to obtain the discretised equations of motion of plates. The effects of plate geometry, boundary conditions, material properties and foundation parameters on nonlinear vibration behavior of plates are presented.

Virtual ground monitoring for high fault coverage of linear analog circuits

  • Roh, Jeongjin
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.2 no.3
    • /
    • pp.226-232
    • /
    • 2002
  • This paper explains a technique to improve the fault coverage of oscillation-test [1-5] for linear analog circuits. The transient behavior of the virtual ground is monitored during oscillation to extract information of the circuit. The limitation of the oscillation-test is analyzed, and an efficient signature analysis technique is proposed to maximize the fault coverage. The experimental result proves that the parametric fault coverage can be significantly increased by the proposed technique.

Analysis of Complemented CA Derived from a Linear TPMACA

  • Cho, Sung-Jin;Kim, Seok-Tae;Park, Un-Sook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2001.05a
    • /
    • pp.688-691
    • /
    • 2001
  • By using basic paths in the 0-tree of a linear TPMACA C we obtain the state-transition diagram of complemented CA C'derived from C such that the complement vector is a nonzero attractor of C. Also we analyze the behavior of C'.

  • PDF

Bayesian Prediction under Dynamic Generalized Linear Models in Finite Population Sampling

  • Dal Ho Kim;Sang Gil Kang
    • Communications for Statistical Applications and Methods
    • /
    • v.4 no.3
    • /
    • pp.795-805
    • /
    • 1997
  • In this paper, we consider a Bayesian forecasting method for the analysis of repeated surveys. It is assumed that the parameters of the superpopulation model at each time follow a stochastic model. We propose Bayesian prediction procedures for the finite population total under dynamic generalized linear models. Some numerical studies are provided to illustrate the behavior of the proposed predictors.

  • PDF

Synchronization of Chaos in a Dual-structured System Consisting of Two Identical Piecewise-linear Systems

  • Kita, Toshihiro
    • Proceedings of the IEEK Conference
    • /
    • 2002.07c
    • /
    • pp.2012-2015
    • /
    • 2002
  • Synchronization phenomena of chaos observed in a dual-structured system is presented. The system is consisting of two identical piecewise-linear systems and the simple coupling between the two systems enables the synchronization of the chaotic behavior. An application of the proposed dual-structure to a real power system for the parameter value identification is also presented.

  • PDF

Seismic performance evaluation for steel MRF: non linear dynamic and static analyses

  • Calderoni, B.;Rinaldi, Z.
    • Steel and Composite Structures
    • /
    • v.2 no.2
    • /
    • pp.113-128
    • /
    • 2002
  • The performance of steel MRF with rigid connections, proportioned by adopting different capacity design criteria, is evaluated in order to highlight the effectiveness of static non-linear procedure in predicting the structural seismic behavior. In the framework of the performance-based design, some considerations are made on the basis of the results obtained by both dynamic time histories and push-over analyses, particularly with reference to the damage level and the structure ability to withstand a strong earthquake.

A Prediction Model for Health Promoting Behavior of The Korean Elderly (한국노인의 건강행위 예측모형구축)

  • 박영주;이숙자;박은숙;장성옥
    • Journal of Korean Academy of Nursing
    • /
    • v.29 no.2
    • /
    • pp.281-292
    • /
    • 1999
  • This study was designed to construct a model that predicts the health promoting behavior of the Korean elderly. Data were collected by self-reported questionaires from 254 Korean elderly in seoul, from June 1 to July 15, 1998. Data were analyzed by descriptive statistics and correlational analysis using pc-SAS program. The Linear Structural Modeling(LISREL) 8.0 program was used to find the best fit model which predicts causal relationships of variables. The overall fit of the hypothetical model to the data was moderate[X$^2$=249.83(df=83, p=.00), RMR=.07, GFI=.90, NNFI=.92, NFI =.91]. The predictable variables of health promoting behavior of the Korean elderly were social activity. social support. self-integrity and helplessness except the perceived health status. These variables explained 17.1% of health promoting behavior of the Korean elderly.

  • PDF

On the Description of Constrained Static Behavior of Continuous System

  • Eun, Hee-Chang;Lee, Min-Su;Bae, Chung-Yeol
    • Architectural research
    • /
    • v.9 no.1
    • /
    • pp.39-45
    • /
    • 2007
  • The static behavior of continuous system is described by the elastic curve method or is approximately analyzed by a finite element method to be modeled as a discrete system. If a continuous system is constrained by linear constraints which restrict its static behavior, its behavior can be approximately described by the finite element method. It is not easy to describe the constrained behavior by continuous coordinate system. Starting from the generalized inverse method provided by Eun, Lee and Chung, this study is to expand the equation to the continuous systems, to perform the structural analysis of the beam under a uniform loading with interior spring supports, and to investigate the validity of the proposed method through applications.