Noise-induced parametric oscillations in nonlinear oscillator

The onset of stochastic oscillations in a nonlinear oscillator with a noise-modulated frequency is considered. It is demonstrated that these oscillations are characterized by the existence of an attractor (i.e., are independent of the initial conditions), but do not exhibit the phenomenon of synchronization typical of self-oscillatory systems.     

Continuous models in nonlinear thermomechanics of binary systems

We study some general problems connected with the construction of thermodynamic models in the mechanics of two-component elastic bodies. Principal relations of the model are established on the basis of fundamental concepts and approaches of nonlinear continuum mechanics and nonequilibrium thermodynamics. We also demonstrate that systems of this sort can be described without using chemical potentials in the explicit form.Center of Mathematical Simulation. Pidstryhach Institute for Applied Problems in Mathematics and Mechanics, Ukrainian Academy of Sciences, L'viv. Translated from Fiziko-Khimicheskaya Mekhanika Materialov, Vol. 31, No. 4, pp. 7–15, July – August, 1995.     

Influencing factors of synchronization in manufacturing systems

Manufacturing systems exhibit two types of synchronisation phenomena: logistics and physics. Previous research has established synchronisation measures for both types and has shown that they are related to the due date performance. However, there is a lack of knowledge about the factors triggering synchronisation emergence as well as a holistic understanding of synchronisation effects on logistics performance. Thus, this research aims to further explore the relation between synchronisation, its influencing factors and its effect on logistics performance. Based on a profound literature review, we derive first hypotheses on the cause-and-effect-relationships between structural and dynamic properties of a manufacturing system and the emergence of logistics and physics synchronisation as well as logistics performance. By conducting a discrete-event simulation study on diverse manufacturing system types (line, flow shop and job shop production), we are able to test these hypotheses. We conclude that manufacturing network architecture as a structural property as well as processing time variability and system workload as dynamic properties may be exploited for an advanced and synchronisation-oriented manufacturing system design.     

Theory of nucleation in binary systems

A method of calculating the rate of nucleation in phase transformations in binary mixtures is proposed.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 2, pp. 201–204, August, 1984.     

Reaction diffusion in heterogeneous binary systems

A physicochemical approach to the solid-state growth kinetics of compound layers in multiphase binary heterogeneous systems is proposed. This appmach seems to be more adequate than the existing diffusional one. A least it permits one to understand without any speculationtive suppositions why the number of compound layers in reaction couples is in general far less than the number of chemical compounds in binary phase diagrams at the temperatures under investigation.     

Reaction diffusion in heterogeneous binary systems

A theory is proposed for solid-state growth of the chemical compound layers at the interface between two elementary substances one of which is solid at the given temperature while the other may be solid, liquid or gaseous. Not only the rates of diffusional transport of the reacting species through the growing layers but also the rates of chemical reactions taking place at the interfaces between the phases involved in the interaction are taken into account. This theory seems to be more consistent with the available experimental data than the existing “diffusional” theory.     

Viscosity of binary liquid systems

A method is proposed for calculating the viscosity of binary liquid systems (solutions, mixtures) involving the concentrations and properties of initial components on the basis of the theory of generalized conductivity.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 30, No. 1, pp. 115–121, January, 1976.     

Shannon's theory in nonlinear systems

An exponential growth in the capacity of optical networks has taken place over the last decade, but the extent to which future capacity growth can continue is limited by physical laws governing signal propagation through optical fibres. While the classic theory of communication developed by Claude Shannon allows the analytical calculation of information spectral density limits for linear channels with white additive Gaussian noise, the nonlinear nature of optical fibres makes these limits much more difficult to determine for long-haul optical transmission. Accurately predicting the ultimate limits has been the focus of much recent research. This paper describes the sources of linear and nonlinear signal impairments, reviews progress on extending Shannon's theory to the case of nonlinear signal propagation, and discusses new optical and electronic signal processing techniques that may be used to approach the Shannon limit in future networks.     

Phase transformations in water-aliphatic alcohol binary systems

The parameters of liquid-vapor phase transitions p _s , ρ _s , T _s and critical points p _c, ρ_c, T _c were determined from the experimental data on the p, ρ, T, x-dependences of aqueous solutions of aliphatic alcohols (methanol, ethanol, n-propanol) that contain 0.2,0.5, and 0.8 mole fractions (x) of ethanol and correspond to single-phase (gas, liquid), two-phase, or subcritical areas. The dependence of the pressure of saturated vapor in solutions on the temperature and density was described by means of the expansion of the compressibility factor Z = p/RTρ _m in powers of the density and temperature along the coexistence curve away from the critical point. The temperature dependence of the density of solutions along the coexistence curve and inside the critical area was fitted using the power functions of parameters ω ～ $\tau ^{\beta _i } $ , τ = (T ? T _c) and ω = (ρ_1,v ? ρ_c)/ρ_c.     

The synchronization and entanglement of optomechanical systems

We investigate synchronization and entanglement in two coupled cavity optomechanical systems. The classical synchronization, quantum synchronization and entanglement of the two cavity fields and the two mechanical oscillators are analysed, respectively. Our results show that the two cavity resonators are synchronization without entanglement, while the two mechanical oscillators are entangled with quantum-phase synchronization. We conclude that the quantum synchronization and entanglement have no affirmatory relationship although they are both signature of correlation.     

Mutual synchronization and desynchronization of Lorenz systems

The dynamics of two symmetrically coupled Lorenz systems is investigated by means of a numerical experiment. A bifurcation analysis of the synchronization process is presented. The results are compared with numerical experiments. It is shown that changing the coupling can synchronize or desynchronize the subsystems. Pis’ma Zh. Tekh. Fiz. 24, 22–30 (April 12, 1998)     

Phase synchronization of switching processes in stochastic bistable systems

The concept of an analytic signal is used to show that the stochastic synchronization of bistable systems corresponds to locking of the instantaneous phase of the oscillations in complete agreement with the classical theory of phase synchronization. Pis’ma Zh. Tekh. Fiz. 24, 12–19 (August 12, 1998)     

Spatiotemporal chaos synchronization in beam-plasma systems with supercritical current

It is established that coupled beam-plasma systems with supercritical current can feature the phenomenon of chaotic synchronization. As the coupling between subsystems increases, a distributed beam-plasma system exhibits the transition from asynchronous behavior via phase synchronization to the state of complete chaotic synchronization. The phenomenon of chaotic synchronization is studied using a method developed previously on the basis of the introduction of a continuous manifold of phases of the chaotic signal.     

Appearance of generalized synchronization in mutually coupled beam-plasma systems

The phenomenon of generalized synchronization onset between mutually coupled beam-plasma systems (Pierce diodes) with supercritical currents has been discovered. It is established that the appearance of a synchronous regime is related to the change in one Lyapunov exponent from a positive to negative value. The results of the analysis are confirmed by the nearest-neighbor method.     

Mutual synchronization of switching processes in coupled Lorenz systems

A numerical analysis is made of the synchronization of the mean switching frequencies in two symmetrically coupled Lorenz systems functioning in a chaotic regime. The observed effect on the coupling-mismatch parameter plane corresponds to a region of synchronization of the switching processes, within which the mean switching frequencies coincide to a given accuracy. Pis’ma Zh. Tekh. Fiz. 23, 14–19 (April 26, 1997)     

Damage detection in initially nonlinear systems

The primary goal of Structural Health Monitoring (SHM) is to detect structural anomalies before they reach a critical level. Because of the potential life-safety and economic benefits, SHM has been widely studied over the past two decades. In recent years there has been an effort to provide solid mathematical and physical underpinnings for these methods; however, most focus on systems that behave linearly in their undamaged state—a condition that often does not hold in complex “real-world” systems and systems for which monitoring begins mid-lifecycle. In this work, we highlight the inadequacy of linear-based methodology in handling initially nonlinear systems. We then show how the recently developed autoregressive support vector machine (AR-SVM) approach to time-series modeling can be used for detecting damage in a system that exhibits initially nonlinear response. This process is applied to data acquired from a structure with induced nonlinearity tested in a laboratory environment.     

Solid-liquid interfacial energies in binary and pseudo-binary systems

A simple thermodynamic model of the solid-liquid interface in binary systems is presented and used as a means of estimating the solid-liquid interfacial energy, _SL, in such systems. The model is extended to pseudo-binary systems such as transition metal carbide/liquid metal systems. In combination with wetting data the estimated _SL values can be used to estimate the surface energy of the solid, _SV. In most cases, estimated values of _SL and _SV are in good agreement with experimentally determined values.     

横纵激励下几何非线性复合材料层合梁的混沌同步

本文基于里兹-伽辽金法,将考虑几何非线性的一端固支一端夹支复合材料层合梁的控制方程简化为典型的Duffing方程;引入了Duffing-Van Der Pol系统,通过两种系统的分岔图说明了它们共同达到混沌时的参数值;通过广义投影同步法,实现了Duffing系统和Duffing-Van Der Pol系统的精确同步,得到了实现两种系统同步的控制器;分别将两种系统通过Matlab进行了数值仿真,得到了两种系统的同步误差曲线图、二维相图和三维相图,从而验证了混沌同步的准确性。