Analysis of free vibration of nano plate resting on Winkler foundation

Present paper deals with the vibration analysis of nano plate supported by Winkler foundation using Eringen’s elasticity theory with Classical Plate theory. Rayleigh-Ritz method has been employed in this study for finding frequencies of plate subjected to different edge conditions. The obtained results are first tested for convergence and then validated with the published literature. Further study is carried out to analyse the effect of various parameters on natural nondimensional frequencies of nano plate resting on Winkler foundation. The study reveals that the non-local effect has significant effect on vibration behaviour of nano plate resting on elastic foundation. Observations shows that on increasing the Winkler foundation modulus and aspect ratio the nondimensional frequency parameters increases

Imatinib and Thyroid Dysfunction in BCR-ABL Positive CML Patients

Background: Thyroid dysfunction is a known adverse effect of some tyrosine kinase inhibitors like sunitiniband sorafenib while imatinib hasbeen shown to induce hypothyroidism and increased requirement of levothyroxine in thyrectomizedpatients. Very few retrospective studies are available for CML patients treated with imatinib,which havedemonstrated conflicting effects on thyroid function.Experimental design: We have prospectively studied thyroid function at baseline and at 6 months of imatinib treatment in 30 newly diagnosed BCR-ABL positive CML patients.Results: Two (6.7%) patients had subclinical hypothyroidism at diagnosis with the prevalence not being different from general population. Though the TSH levels increased significantly from baseline (3.80±2.00 mIU/L vs. 3.14±1.65 mIU/L, p =0.016) after6 months of treatment, 90% of the patients remained euthyroid. Only 3 patients had subclinical hypothyroidism.Conclusion: Imatinib did not have any significant impact on thyroid function in CML patients but may possibly alter the peripheral metabolism of thyroid hormones

A novel chaotic system without equilibria, with parachute and thumb shapes of Poincare map and its projective synchronisation

In this paper, a three-dimensional novel chaotic system and its projective synchronisation are investigated. The proposed chaotic system has no equilibria. The topological structure of proposed chaotic system is different form Lorenz, Rossler and Chen systems. Different qualitative and quantitative tools such as time series, phase plane, Poincare section, bifurcation plot, Lyapunov exponents, Lyapunov spectrum, and Lyapunov dimension are used to evidence the chaotic behaviour of the proposed system. Further, the projective synchronisation between the proposed chaotic systems is achieved using nonlinear active control. Active control laws are designed, by using sum of the relevant variables of the proposed chaotic systems, to ensure the convergence of error dynamics. The required global asymptotic stability condition is derived using Lyapunov stability theory. Simulation is done in MATLAB environment to verify the theoretical approach. Simulation results reveal that the objectives of the paper are achieved successfully

Memristor-based novel complex-valued chaotic system and its projective synchronisation using nonlinear active control technique

In this paper, a flux controlled memristor-based novel complex-valued chaotic system and its projective synchronisation is investigated. The proposed complex-valued chaotic system has line and plane of equilibria, i.e. an infinite number of equilibria. Different qualitative and quantitative tools such as time series, phase plane, Poincaré section, Lyapunov exponents, Lyapunov spectrum, and Lyapunov dimension are used to evidence the chaotic behaviour of the proposed complex-valued system. Further, the projective synchronisation between the proposed complex-valued chaotic systems is achieved using nonlinear active control. Active control laws are designed, by using sum of the relevant variables of the proposed complex-valued chaotic systems, to ensure the convergence of error dynamics. The required global asymptotic stability condition is derived using Lyapunov stability theory. Simulation is done in MATLAB environment to verify the theoretical approach. Simulation results reveal that the objectives of the paper are achieved successfully

Multistability, coexisting behaviours and control of fractional order dissipative small scale grid with disturbances and noise

This paper introduces nonlinear analysis and control of a fraction order small-scale grid (SSG) under the influence of disturbances and noise. Random wind power supply and uncertain load demand are considered as disturbances while the additive white Gaussian noise is considered as external noise. The nonlinear dynamic behaviours such as multistability and coexisting bifurcation behaviours are investigated along with period-2, period doubling bifurcation route to chaos and instability (chaos breaking) of the rotor angle which is not expected under normal operating condition and reveal stability issue in the proposed SSG. Also, the presence of nontrivial behaviours, multistability and coexistence of attractors, may be of capital importance in understanding dynamic remedy of the fractional order SSG behaviour since serious impediments may occur even after the present required safeguard. An adaptive fractional second order PID sliding mode control (AFSO-PIDSMC) is proposed to control the chaos and multistability behaviours in the fractional order SSG. The proposed control technique includes the design adaptive control based on the designed fractional and second-order PID sliding mode control. Required asymptotic stability condition is derived by using Lyapunov stability theory. Furthermore, the proposed control technique is compared and has fast convergence, parameter estimation and chatter-free response. Numerical simulations are performed in MATLAB environment and validate the theoretical aspects

Inter network synchronisation of complex dynamical networks by using smooth proportional integral SMC technique

This paper puts forward the inter network synchronisation of complex dynamical networks (CDNs) using drive-response philosophy. The inter networks consist of a drive network (each node represents a hyperchaotic system) and a response network (consists of chaotic system at each node). Synchronisation is achieved using a novel proportional integral (PI) based sliding mode control (SMC) scheme and inter network synchronisation criterion is derived. Unlike the conventional SMC technique, the proposed proportional integral-sliding mode control (PI-SMC) technique does not result decoupled error dynamics. A smooth switching surface is designed to eliminate the chattering effect. The different network configurations: small-world and scale-free networks, are simulated and the simulation results show that the proposed synchronisation scheme is effective for the inter network synchronisation between two or more CDNs. The effect of relevant parameters on the synchronisation process in the Watts-Strogatz (WS) small-world and Barabasi-Albert (BA) scale-free networks are analysed. Finally, the proposed PI-SMC technique is compared with standard SMC technique to justify the advantages over the standard SMC technique

Microscopic chaos control of chemical reactor system using nonlinear active plus proportional integral sliding mode control technique

This paper puts forward the microscopic chaos control in the deterministic dynamics of the chemical reactor system. First, the dynamic behavior of the chemical reactor system is explored for some of the parameters and chaotic behavior is investigated. Phase plane, bifurcation plots and Lyapunov exponents are presented to verify the chaotic behavior. Second, nonlinear active plus proportional integral sliding mode control (NA-PISMC) is proposed to control microscopic chaos in the chemical reactor system. A proportional integral switching surface is proposed to achieve the stability condition of the error dynamics and controller is designed by using the relevant variables of the chemical system. Unlike the open loop and open plus closed loop control techniques, the design of proposed controller does not require the parameter perturbation. The required stability condition is derived based on Lyapunov stability theory. Simulation is done in MATLAB environment. Numerical simulation results are presented in order to show the effective performances of the proposed controller design. Simulation results correspond that the objectives of chaos existence and chaos control are achieved successfully

Chaos control in biological system using recursive backstepping sliding mode control

This paper puts forward the control of chaos in the biological system. A new controller based on recursive backstepping sliding mode control is proposed such that it can control the chaotic dynamics in the biological system to stabilize at any position or to track any trajectory that is a smooth function of time. A proportional integral switching surface is proposed to achieve the stability condition of the error dynamics. Unlike the open loop and open plus closed loop control techniques, the design of proposed controller does not require the parameter perturbation. The required stability condition is derived based on Lyapunov stability theory. Simulation is achieved in MATLAB environment. Numerical simulation results are presented in order to show the effective verification of the proposed controller design. Simulation results correspond that the objective of chaos control is achieved successfully