A memcapacitor-based hyperchaotic conservative system

2021 ◽  
Vol 31 (12) ◽  
pp. 123116
Author(s):  
Wei Zhou ◽  
Guangyi Wang ◽  
Herbert Ho-Ching Iu
Keyword(s):  
2017 ◽  
Vol 19 (1) ◽  
pp. 21-44
Author(s):  
Gráinne McKeever ◽  
Mark Simpson

The post-2007 financial crisis has brought renewed interest in a European Unemployment Benefit Scheme (EUBS) as a manifestation of solidarity between citizens of different Member States and an economic stabiliser in the event of future asymmetric shocks. The EU-wide benefit would operate in tandem with existing national unemployment benefits. This creates challenges of compatibility given the diversity of approaches to social security within the Union, based on at least four philosophies of welfare: liberal, conservative, social democratic and southern European. This article examines potential legal, operational and political difficulties associated with marrying a EUBS that is at heart a conservative system of social insurance to the UK’s liberal welfare state. Few legal obstacles exist and although the addition of a new, earnings-related benefit to an already complex mix of social protection would raise significant operational issues, these need not be insurmountable. However, fundamental ideological differences would have rendered the EUBS as proposed politically ill-matched with the UK even absent the June 2016 vote to leave the EU. A contributory income maintenance benefit is a poor fit with a residual, largely means-tested national system whose role is limited to offering protection against severe poverty while maintaining work incentives and minimising costs.


Complexity ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Min Zheng ◽  
Tangqing Yuan ◽  
Tao Huang

In order to guarantee the passivity of a kind of conservative system, the port Hamiltonian framework combined with a new energy tank is proposed in this paper. A time-varying impedance controller is designed based on this new framework. The time-varying impedance control method is an extension of conventional impedance control and overcomes the singularity problem that existed in the traditional form of energy tank. The validity of the controller designed in this paper is shown by numerical examples. The simulation results show that the proposed controller can not only eliminate the singularity problem but can also improve the control performance.


Symmetry ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1489
Author(s):  
Yongbo Guo ◽  
Fansheng Wang

Based on the rigid finite element method and multibody dynamics, a discrete model of a flexible conveyor belt considering the material viscoelasticity is established. RFE (rigid finite element) and SDE (spring damping element) are used to describe the rigidity and flexibility of a conveyor belt. The dynamic differential equations of the RFE are derived by using Lagrange’s equation of the second kind of the non-conservative system. The generalized elastic potential capacity and generalized dissipation force of the SDE are considered. The forward recursive formula is used to construct the conveyor belt model. The validity of dynamic equations of conveyor belt is verified by field test. The starting mode of the conveyor is simulated by the model.


2000 ◽  
Vol 122 (4) ◽  
pp. 429-433 ◽  
Author(s):  
Kumar Vikram Singh ◽  
Yitshak M. Ram

The motion of a particular degree-of-freedom in a harmonically excited conservative system can be vanished by attaching an appropriate dynamic absorber to it. It is shown here that under certain conditions, which are characterized in the paper, the steady state motion of a damped system may be completely absorbed, without loss of stability, by active control implementing a single sensor and an actuator. The results are established theoretically and they are demonstrated by means of analytical examples. [S0739-3717(00)02104-8]


2014 ◽  
Vol 15 (5) ◽  
pp. 1237-1265 ◽  
Author(s):  
Remi Abgrall ◽  
Harish Kumar

AbstractThe numerical simulation of non conservative system is a difficult challenge for two reasons at least. The first one is that it is not possible to derive jump relations directly from conservation principles, so that in general, if the model description is non ambiguous for smooth solutions, this is no longer the case for discontinuous solutions. From the numerical view point, this leads to the following situation: if a scheme is stable, its limit for mesh convergence will depend on its dissipative structure. This is well known since at least [1]. In this paper we are interested in the “dual” problem: given a system in non conservative form and consistent jump relations, how can we construct a numerical scheme that will, for mesh convergence, provide limit solutions that are the exact solution of the problem. In order to investigate this problem, we consider a multiphase flow model for which jump relations are known. Our scheme is an hybridation of Glimm scheme and Roe scheme.


1960 ◽  
Vol 64 (599) ◽  
pp. 697-699 ◽  
Author(s):  
R. P. N. Jones ◽  
S. Mahalingam

The Rayleigh-Ritz method is well known as an approximate method of determining the natural frequencies of a conservative system, using a constrained deflection form. On the other hand, if a general deflection form (i.e. an unconstrained form) is used, the method provides a theoretically exact solution. An unconstrained form may be obtained by expressing the deflection as an expansion in terms of a suitable set of orthogonal functions, and in selecting such a set, it is convenient to use the known normal modes of a suitably chosen “ basic system.” The given system, whose vibration properties are to be determined, can then be regarded as a “ modified system,” which is derived from the basic system by a variation of mass and elasticity. A similar procedure has been applied to systems with a finite number of degrees of freedom. In the present note the method is applied to simple non-uniform beams, and to beams with added masses and constraints. A concise general solution is obtained, and an iteration process of obtaining a numerical solution is described.


2018 ◽  
Vol 68 (2) ◽  
pp. 105-124 ◽  
Author(s):  
Milan Žmindák

AbstractIn this paper the concept of generalized form of proportional damping is proposed. Classical modal analysis of non-conservative continua is extended to multi DOF linear dynamic systems with asymmetric matrices. Mode orthogonality relationships have been generalized to non-conservative systems. Several discretization methods of continua are presented. Finally, an expression for derivatives of eigenvalues and eigenvectors of non-conservative system is presented. Examples are provided to illustrate the proposed methods.


2017 ◽  
Vol 2 ◽  
pp. 9-15
Author(s):  
Iryna Svyatovets

The problem is considered for constructing a minimax control for a linear stationary controlled dynamical almost conservative system (a conservative system with a weakly perturbed coefficient matrix) on which an unknown perturbation with bounded energy acts. To find the solution of the Riccati equation, an approach is proposed according to which the matrix-solution is represented as a series expansion in a small parameter and the unknown components of this matrix are determined from an infinite system of matrix equations. A necessary condition for the existence of a solution of the Riccati equation is formulated, as well as theorems on additive operations on definite parametric matrices. A condition is derived for estimating the parameter appearing in the Riccati equation. An example of a solution of the minimax control problem for a gyroscopic system is given. The system of differential equations, which describes the motion of a rotor rotating at a constant angular velocity, is chosen as the basis.


2021 ◽  
pp. 1-51
Author(s):  
Zhenhang Wu ◽  
Sebastien Seguy ◽  
Manuel Paredes

Abstract This work mainly concentrates on the optimization of cubic and bistable NES to find the maximum efficiency point under harmonic excitation. The conservative system is considered to reveal the inner property of the damping system. With the application of the multiple scales method and the complex variables method, the threshold of excitation and different response regimes are distinguished under the assumption of 1:1 resonance. The maximum efficiency point of cubic and bistable NES occurs when SMR disappears. The factors that affect the optimal efficiency limit are explored. The result indicates that the maximum absorption efficiency level is mainly determined by the damping parameters. Compared with the cubic case, the bistable case involves more complex regimes in terms of chaos oscillation. The influence of damping parameters on the chaos threshold is discussed to adopt different energy levels. With the help of analytical predictions, the proper nonlinear stiffness is determined for certain harmonic excitation. This work offers some fundamental insights into the optimal design of cubic and bistable NES.


2021 ◽  
Author(s):  
Dmitrii Skubov ◽  
Ivan Popov ◽  
Pavel Udalov

Abstract The main task of our work is determination of possible levitation of micro-ring with eddy current in magnetic field of down ring with set alternating current and determination of critical value of «ohmic» damping separated field of parameters, at which motions of suspension ring transit from divergent to meeting to steady-state equilibrium position. I. e. in this critical case the motion practically coincides with motions of conservative system. The possibility of gyroscopic stabilization of suspension ring taking into account initial set rotation is considered. Thereby it can serve as contactless micro-gyroscope.


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