Results 11 to 20 of about 937 (215)
Bulletin of the Belgian Mathematical Society - Simon Stevin, 2007 The authors study an interesting problem involving periodic solutions having a symmetry induced by an orthogonal matrix \(A\) for which there is an integer \(p\) such that \(A^p\) is the identity. More precisely, given \(T>0\), they look for solutions \(x\) satisfying the relation \(x(t+T)=A x(t)\), for every \(t\). These solutions are \(pT\)-periodic.
Feckan, M., Ma, R., Thompson, B.
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Forced oscillation of second-order nonlinear dynamic equations on time scales
Electronic Journal of Qualitative Theory of Differential Equations, 2009 In this paper, by defining a class of functions, we establish some oscillation criteria for the second order nonlinear dynamic equations with forced term $$ x^{\Delta\Delta}(t)+a(t)f(x(q(t)))=e(t) $$ on a time scale $\mathbb{T}.$ Our results unify the ...
Tongxing Li +3 more
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Location and Mechanism Analysis of Oscillation Source in Power Plant
IEEE Access, 2020 A generation unit that is poorly damped or has periodical mechanical power outputs from its prime mover can become a source of oscillation in a bulk power system. Choosing the proper electric quantity to extract the oscillation characteristics is crucial
Yanhui Xu, Zheng Gu, Kai Sun
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General Forced Oscillations in a Real Power Grid Integrated with Large Scale Wind Power
Energies, 2016 According to the monitoring of the wide area measurement system, inter-area oscillations happen more and more frequently in a real power grid of China, which are close to the forced oscillation.
Ping Ju +4 more
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Shanghai Jiaotong Daxue xuebao, 2022 There exists the subsynchronous oscillation (SSO) instability risk in large-scale photovoltaic(PV) grid-connected systems with series compensation, which is generally explained by the negative damped oscillation theory.
LIN Yong, KANG Jiale, YU Hao, CHEN Honglin, YANG Yanji, CHEN Wuhui
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Survey on forced oscillations in power system
Journal of Modern Power Systems and Clean Energy, 2017 The oscillations in a power system can be categorized into free oscillations and forced oscillations. Many algorithms have been developed to estimate the modes of free oscillations in a power system.
Mohammadreza GHORBANIPARVAR
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International Journal of Differential Equations, 2016 We are concerned with the interval oscillation of general type of forced second-order nonlinear dynamic equation with oscillatory potential of the form rtg1xt,xΔtΔ+p(t)g2(x(t),xΔ(t))xΔ(t)+q(t)f(x(τ(t)))=e(t), on a time scale T.
Hassan A. Agwa +2 more
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Influence of the ageing process on the resistive and reactive properties of the respiratory system
Clinics, 2009 INTRODUCTION: In an increasingly old society, the study of the respiratory system changes and new techniques dedicated to older patients are of interest in physiologic studies as well as in the diagnosis of respiratory diseases.
Caio Vinicius Villalón e Tramont +4 more
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Transitional Characteristics of Phase Shift in Lock-in Phenomena of an Oscillating Cylinder
Journal of Fluid Science and Technology, 2009 In this study, characteristics of phase lag between displacement of forcibly oscillating test body and velocity fluctuation caused by vortex formation behind the test body were investigated.
Hiroyuki HANIU +4 more
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Numerical investigation of vortex shedding and vortex-induced vibration for flexible riser models
International Journal of Naval Architecture and Ocean Engineering, 2010 The numerical study about the vortex-induced vibration and vortex shedding in the wake has been presented. Prior to the numerical simulation of flexible riser systems concerning engineering conditions, efficiency validating of the proposed FSI solution ...
Zheng-Shou Chen, Wu-Joan Kim
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