Open Access
ARTICLE
A. Takahashi1, T. Shibata2, K. Motoyama3, K. Misaji4
CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.1, pp. 1-15, 2017, DOI:10.3970/cmes.2017.113.001
Abstract A method for reducing the damage to a structure caused by an earthquake namely, using laminated rubber for seismic isolation is proposed, and the vibration characteristics of the rubber (which minimizes the seismic response of the structure during an earthquake) is optimized. A method called “Equivalent Linear System using Restoring Force Model of Power Function Type” (PFT-ELS) is applied to nonlinear vibration analysis of the rubber. In that analysis, a building with 15 layers of the laminated rubber is modeled. The seismic response of the building is analyzed, and the usefulness of the laminated rubber is demonstrated by comparing the… More >
Open Access
ARTICLE
Rongxing Duan1, Yanni Lin1, Longfei Hu1
CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.1, pp. 17-34, 2017, DOI:10.3970/cmes.2017.113.015
Abstract Fault tolerant technology has greatly improved the reliability of modern systems on one hand and makes their failure mechanisms more complex on the other. The characteristics of dynamics of failure, diversity of distribution and epistemic uncertainty always exist in these systems, which increase the challenges in the reliability assessment of these systems significantly. This paper presents a novel reliability analysis framework for complex systems within which the failure rates of components are expressed in interval numbers. Specifically, it uses a dynamic fault tree (DFT) to model the dynamic fault behaviors and copes with the epistemic uncertainty using Dempster- Shafer (D-S)… More >
Open Access
ARTICLE
Subhankar Sen1, Sanjay Mittal2, *
CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.1, pp. 35-55, 2017, DOI:10.3970/cmes.2017.113.033
Abstract The evolution of far wake of stationary elliptic cylinders with angle of attack is investigated for the unsteady flow at Re = 200 using a stabilized finite- element method. The Reynolds number, Re, is based on the major axis of cylinder and free-stream speed. Cylinder aspect ratios, AR considered are 0.2, 0.5 and 0.8 while the angle of attack, α varies from 0◦ to 90◦. With increasing α, the Karman or primary shedding frequency of each cylinder decreases monotonically while the primary wavelength and time-averaged as well as r.m.s. drag increase monoton- ically. The time-averaged lift and moment coefficients initially… More >
Open Access
ARTICLE
Li Bin1,2,3, Fang Hongyuan1,2,3,*, He Wei4, Sun Bin1
CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.1, pp. 57-69, 2017, DOI:10.3970/cmes.2017.113.054
Abstract The cutter head will be stuck when the shield machine pass through the area existing anchor left by foundation construction of surrounding high-rise building. Subsurface excavation method is an efficient way to remove the existed anchor. In this paper, a three-dimensional finite element model is developed to study stability of cross-channel excavation. The time-spatial effects of arch crown settlement, intrados uplift and side wall horizontal convergence are analyzed according to different excavation size, lining thickness and lining order. The results show that the excavation size is the main factor to control the deformation of the surrounding soil, especially in arch… More >
Open Access
ARTICLE
K. Abe1, H. Fujii1, S. Yoshimura1
CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.1, pp. 71-87, 2017, DOI:10.3970/cmes.2017.113.068
Abstract Microscopic traffic simulations are useful for solving various traffic- related problems, e.g. traffic jams and accidents, local and global environmental and energy problems, maintaining mobility in aging societies, and evacuation plan- ning for natural as well as man-made disasters. The origin-destination (OD) matrix is often used as the input to represent traffic demands into traffic simulators. In this study, we propose an indirect method for estimating the OD matrix using a traffic simulator as an internal model. The proposed method is designed to output results that are consistent with the input of the simulator. The method consists of the following… More >
Open Access
ARTICLE
Yunpeng Ma1, Lifeng Wang1, *, Mingxu Yi1
CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.1, pp. 89-108, 2017, DOI:10.3970/cmes.2017.113.086
Abstract In this paper, an analytical time domain formulation based on Ffowcs Williams-Hawkings (FW-H) equation is derived for the prediction of the acoustic velocity field generated by moving bodies. This provides the imposition of the Neumann boundary condition on a rigid scattering surface. In order to calculate the scattering sound pressure of the duct, a thin-body boundary element method (BEM) has been proposed. The radiate sound pressure is calculated using the acoustic analogy FW-H equation. The scattering effect of the duct wall on the propagation of the sound wave is presented using the thin-body BEM. Computational results for a pulsating sphere,… More >
Open Access
ARTICLE
T. V. Viknesh1, V. Manik,an
CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.1, pp. 109-116, 2017, DOI:10.3970/cmes.2017.113.107
Abstract The working of Canonical switching cell (CSC) converter was studied and its equivalent circuit during ON and OFF states were obtained. State space model of CSC converter in ON and OFF states were developed using the Kirchhoff laws. The state space matrices were used to construct the transfer functions of ON & OFF states. The step response of the converter was simulated using MATLAB. The step response curve was obtained using different values of circuit components (L, C1, C2 and RL)and optimized. The characteristic parameters such as rise time, overshoot, settling time, steady state error and stability were determined using… More >