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In this paper, the synchronization of discrete-time complex dynamical network with dynamic links is investigated. From the angle of large-scale system, if the links and nodes are time-varying, the complex dynamical network may be regarded to be composed of nodes subsystem (NS) and links subsystem (LS). The weighted value of links between nodes can be regarded as the state variables of LS, the above two subsystems are mutually coupled. The two subsystems are modeled mathematically by the state difference equations, especially, the dynamics of LS is modeled as Riccati matrix difference equation without control input. Different from the previous researches, this work concerns simultaneously the dynamics of LS and NS, by which the synchronization of NS is investigated. Associated with the given dynamic reference target for LS, the nodes controller is synthesized to ensure the state synchronization of NS to be achieved with the assistance of the LS. Finally, the numerical simulation is given to illustrate the effectiveness of the proposed theoretical results in this paper. [ABSTRACT FROM AUTHOR]

In this paper, a reliable and effective local discontinuous Galerkin (LDG) scheme for numerically solving the classical Rosenau–Hyman equation with non-periodic boundary conditions has been proposed. This study employs the third-order nonlinearly stable total variation diminishing Runge–Kutta method and the LDG method, respectively, to discretize the temporal and spatial derivatives. Finally, numerical simulations are performed on various test problems and compared with the exact results as well as results produced by a few other numerical methods, to analyze the reliability and efficiency of the proposed method. The results generated, which validate the expected order of accuracy, are presented through multiple tables. In addition, several graphical representations of the problem are presented to depict the behavior of the solution. [ABSTRACT FROM AUTHOR]

A numerical method which is based on unstructured grids to compute high-temperature ionized air radiation is described. The multi-species N-S equations are used and the chemical model includes 11 species (O2, N2, O, N, NO, NO+, N+, O+, N+2, O+2, e-) and 20 reactions. For simulating thermal non-equilibrium effect, the two-temperature model is considered. The finite volume method (FVM) is used for spatial and directional discretization for the RTE on unstructured grids. The code can deal with different kinds of species and radiative bands. Particularly, the Delta, Epsilon, Beta prime and Gamma prime bands of NO are considered in this paper. The numerical results of MESES-C for hypersonic flow with high-temperature ionized radiation are shown, and compared well with the reference data and experimental data. [ABSTRACT FROM AUTHOR]

A numerical method for the simulation of parachute inflation process is presented in this paper. The unsteady compressible N-S equations are fully coupled with MSD (Mass Spring Damper) structure model and integrated forward in time. The CFD solver is based on an unstructured finite volume algorithm and the preconditioning technique is applied to alleviate the stiffness caused by low Mach number. The Spalart-Allmaras one-equation turbulence model is implemented to evaluate the turbulent viscosity. The whole system (fluid equations and structural model equations) is marched implicitly in time using a dual time stepping method. An overset deforming grids method is adopted in this paper to deal with the very large domain deformation during the parachute inflation process. Finally numerical test is performed to validate the robustness of this method. [ABSTRACT FROM AUTHOR]

Tantalum nitrides (TaN) have attracted much attention as a new material of energy exchangers in insensitive detonators, we mainly investigate its ignition law in this paper. Firstly, the paper utilizes numerical simulation to predict the influence of the substrate material, bridge zone thickness, bridge zone length and width on the ignition action. Then its reliability was verified by experiments, which provided technical support for the design of passivated pyrotechnics. [ABSTRACT FROM AUTHOR]

This paper depicts a ghost cell method to solve the three dimensional compressible time-dependent Euler equations using Cartesian grids for static or moving bodies. In this method, there is no need for special treatment corresponding to cut cells, which complicate other Cartesian mesh methods, and the method avoids the small cell problem. As an application, we present some numerical results for a special moving body using this method, which demonstrates the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

The trigonometric quintic B-spline scheme is used in this research paper to research Zakharov's (ZK) nonlinear dimensional equation's numerical solution. The ZK model's solutions explain the relationship between the high-frequency Langmuir and the low-frequency ion-acoustic waves with many applications in optical fiber, coastal engineering, and fluid mechanics of electromagnetic waves, plasma physics, and signal processing. Three recent computational schemes (the expanded exp (ϕ) -expansion method, generalized Kudryashov method, and modified Khater method) have recently been used to investigate this model's moving wave solution. Many innovative solutions have been established in this paper to determine the original and boundary conditions that allow numerous numerical schemes to be implemented. Here, the trigonometric quintic B-spline method is used to analyze the precision of the collected analytical solutions. To illustrate the precision of the numerical and computational solutions, distinct drawings are depicted. [ABSTRACT FROM AUTHOR]

This paper proposes a new density gradient continuous traffic flow model, and analyzes the linear stability of the model, as well as the bifurcation type of the model. Numerical simulation of the new model verifies the usability of the model. From the perspective of system stability, the bifurcation analysis method is used to analyze the nonlinear traffic phenomena on the expressway. The equilibrium solution of the model is discussed. On this basis, Hopf bifurcation, saddle bifurcation and Bogdanov–Takens bifurcation are obtained, and the existence conditions and fractional types of Hopf bifurcation and saddle bifurcation are obtained. The traffic flow characteristics of Hopf bifurcation and saddle node bifurcation are analyzed. [ABSTRACT FROM AUTHOR]

The primary goal of this paper is to seek solutions to the coupled nonlinear partial differential equations (CNPDEs) by the use of q-homotopy analysis transform method (q-HATM). The CNPDEs considered are the coupled nonlinear Schrödinger–Korteweg–de Vries (CNLS-KdV) and the coupled nonlinear Maccari (CNLM) systems. As a basis for explaining the interactive wave propagation of electromagnetic waves in plasma physics, Langmuir waves and dust-acoustic waves, the CNLS-KdV model has emerged as a model for defining various types of wave phenomena in mathematical physics, and so forth. The CNLM model is a nonlinear system that explains the dynamics of isolated waves, restricted in a small part of space, in several fields like nonlinear optics, hydrodynamic and plasma physics. We construct the solutions (bright soliton) of these models through q-HATM and present the numerical simulation in form of plots and tables. The solutions obtained by the suggested approach are provided in a refined converging series. The outcomes confirm that the proposed solutions procedure is highly methodological, accurate and easy to study CNPDEs. [ABSTRACT FROM AUTHOR]

The evaluation of node importance has great significance to complex network, so it is important to seek and protect important nodes to ensure the security and stability of the entire network. At present, most evaluation algorithms of node importance adopt the single-index methods, which are incomplete and limited, and cannot fully reflect the complex situation of network. In this paper, after synthesizing multi-index factors of node importance, including eigenvector centrality, betweenness centrality, closeness centrality, degree centrality, mutual-information, etc., the authors are proposing a new multi-index evaluation algorithm of identifying important nodes in complex networks based on linear discriminant analysis (LDA). In order to verify the validity of this algorithm, a series of simulation experiments have been done. Through comprehensive analysis, the simulation results show that the new algorithm is more rational, effective, integral and accurate. [ABSTRACT FROM AUTHOR]

Chen–Lee–Liu (CLL) lattice equation is an integrable discretization of the CLL equation which can be used to model the evolution of the self-steepening optical pulses without self-phase modulation. In this paper, the discrete N-fold Darboux transformation (DT) is used to derive the discrete kink multi-soliton solutions in terms of determinant for CLL lattice equation. Soliton fission and fusion interaction structures of such solutions are shown graphically. The details of their evolution are investigated by using numerical simulations, showing that a small noise with amplitude less than or equal to 0.01 produces a strong oscillation and instability of these kink soliton solutions. The discrete generalized perturbation (n,N−n)-fold DT is constructed to express some rational solutions in terms of the determinants of CLL lattice equation by modifying the discrete N-fold DT. Infinitely many conservation laws for CLL lattice equation are constructed based on its Lax representation. Results in this paper might be helpful for understanding the propagation of optical pulses. [ABSTRACT FROM AUTHOR]

A new type of nonlinear sub-grid scale (SGS) model is adopted based on the helicity analysis and is verified by predicting the internal flow in a rotating channel. A stress term that contains helicity constraint is introduced into the original SGS model to construct a nonlinear sub-grid model. This additional term representing the helicity constraint effect in the momentum equations is shown to give predictions that are in better agreement with the experimental data. In this paper, the Detached-Eddy Simulation (DES) and the nonlinear SGS model are used to further study the turbulence statistics of the rotating channel flow. Combining with the Reynolds stress transport equations and the turbulent kinetic energy transport equation, the change of turbulence statistics near the wall of the rotating channel is analyzed. The newly added term changes the turbulent viscosity near the wall, which changes the velocity gradient near the wall and further affects other turbulence statistics near the wall. [ABSTRACT FROM AUTHOR]

In real-world systems, one random failure or targeted attack may lead to the cascading destruction within a system, and even create the systemic collapse among multiple correlated ones. With the help of network science, modeling the cascade failure on complex networks has become a challenging topic. In this paper, we put forward an improved cascading model on two interdependent networks to further explore the impact of the specific detachment logic on the system collapse, where the distinct condition to leave the system for a pair of nodes exists on the two-layered networks. Meanwhile, once the detachment logic is satisfied, two different criteria are adopted to determine whether this pair of nodes will leave the interdependent networks. Through extensive numerical simulations, we analyze the effects of detachment logic, network topology, departure criteria and nodal coupling relationship between layers in detail. It is found that in our detachment logic, both criteria will render the whole system to exhibit the phenomenon of pseudo-steady state and sudden collapse. In particular, two critical thresholds to characterize the evolution of system crashing emerge, which is different from previous findings under other detachment logic conditions on two-layered networks. Current results are conducive to further understanding the crashing behaviors of interdependent networks and designing the more robust networked systems in practice. [ABSTRACT FROM AUTHOR]

With both analytical and numerical methods, local dynamic behaviors including stability and Hopf bifurcation of a new four-dimensional hyper-chaotic system are studied in this paper. All the equilibrium points and their stability conditions are obtained with the Routh–Hurwitz criterion. It is shown that there may exist one, two, or three equilibrium points for different system parameters. Via Hopf bifurcation theory, parameter conditions leading to Hopf bifurcation is presented. With the aid of center manifold and the first Lyapunov coefficient, it is also presented that the Hopf bifurcation is supercritical for some certain parameters. Finally, numerical simulations are given to confirm the analytical results and demonstrate the chaotic attractors of this system. It is also shown that the system may evolve chaotic motions through periodic bifurcations or intermittence chaos while the system parameters vary. [ABSTRACT FROM AUTHOR]

In this paper, a parallel Eulerian hydrocode for the simulation of large scale complicated explosion and impact problem is developed. The data dependency in the parallel algorithm is studied in particular. As a test, the three dimensional numerical simulation of the explosion field in an unlimited atmosphere is performed. The numerical results are in good agreement with the empirical results, indicating that the proposed parallel algorithm in this paper is valid. Finally, the parallel speedup and parallel efficiency under different dividing domain areas are analyzed. [ABSTRACT FROM AUTHOR]

This paper presents the application of an adaptive stencil diffuse interface method to the simulation of dam break problem. The adaptive stencil diffuse interface method is the combination of the diffuse interface method and a stencil adaptive algorithm, where the diffuse interface method is used as the solver, and the adaptive stencil refinement scheme is applied to improve the resolution around the interface so that the fine-scale interface behavior can be captured. In this paper, we use this method to simulate the dam break problem, study the dam height and leading edge position, and compare our results with the experiment data available in the literature. It is shown that the results using the adaptive stencil diffuse interface method agree very well with the experimental results. [ABSTRACT FROM AUTHOR]

The Pseudo-Shock Wave (PSW), which appears when supersonic flow in duct decelerates to subsonic, is a complicated process due to the interaction between boundary layer and shock wave. It significantly affects the performance and efficiency of flow devices. In this paper, PSW in two kinds of variable cross-section ducts, edge-varied and corner-varied, was investigated through CFD numerical simulation. Compared to the rectangular duct, a shorter and wider separation region is appeared in the corner of the edge-varied duct while the strongest separation is laterally propagated across the entire plane of the corner-varied duct's side wall. This makes the performances of varied ducts different from traditional constant cross-section ducts. [ABSTRACT FROM AUTHOR]

As numerical simulation of unsteady flows due to moving boundaries such as flexible flapping-wings is difficult by conventional approaches, an effective strategy which combines mesh deformation based on Delaunay graph mapping and unstructured overset grids is proposed in this paper. A Delaunay graph is generated for each body-fitted grid cluster which overlaps or is embedded within an off-body background grid cluster. At each time step, the graph moves according to the wing's motion and deformation, and the grids move to new positions according to a one-to-one mapping between the graph and the grid. Then, intergrid-boundary definition is implemented automatically for computation. [ABSTRACT FROM AUTHOR]

Hysteresis effect, which has a significant impact on transient characteristics of a pump-turbine, attracts more and more researchers' attention and shows great potential. Influences of hysteresis on dynamic characteristics of a pump-turbine are investigated during the transient process in this paper. Transient trajectories of pump-turbines actually do not match their static operation trajectories, especially in the condition of turbine braking. In order to establish a transient model of a pump-turbine in different moving directions of dynamic trajectories, time delays among the relative parameters are introduced in this paper. Furthermore, effects of hysteresis on the dynamic characteristics of the pump-turbine are analyzed in detail by using numerical simulation. Based on the established transient model, influences of unit head on the dynamic characteristics of the pump-turbine are studied during the bidirectional transient process. The simulation results show the transient characteristic of the pump-turbine can be improved with the enhancement of hysteresis effect. While it gradually loses stability with the increase of hysteresis. The conclusions provide us a new approach for regulating the transient performance and stability of pump-turbines by using hysteresis effect during transient process. [ABSTRACT FROM AUTHOR]

In this paper, the discrete-time complex dynamical networks with dynamic weighted value of connection relationships are regarded to be composed of the node and link subsystems, and the state variables of the two subsystems are mutually coupled. Different from most of the existing researches on synchronization or stabilization of nodes, the emphasis of this paper is on the links instead of nodes. This paper mainly focuses on the generation mechanism of structural balance in the link subsystem, the nodes only play an auxiliary role. Associated with the dynamic coupling term in the link subsystem, the suitable controller is proposed for node subsystem such that the structural balance of link subsystem without control input be achieved indirectly. Finally, a numerical simulation is given to show the effectiveness of the method in this paper. [ABSTRACT FROM AUTHOR]

For complex electromagnetic fields in modern physics, a hybrid isoparametric finite element method (HIFEM) with high accuracy is introduced in the paper. The complex electromagnetic field in an electromagnetic device has been calculated successfully by the hybrid isoparametric finite element method (HIFEM) and the electromagnetic properties of the electromagnetic device under specific work conditions are evaluated. With the help of microcomputers, the electromagnetic simulation given in this paper is very useful in the analysis of operating properties under different work conditions and design of electromagnetic devices. [ABSTRACT FROM AUTHOR]

This paper focuses on the efficiency improvement of a centrifugal fan used in a vacuum cleaner. In order to check the performance of the centrifugal fan system, computational fluid dynamics (CFD) analysis is used. The numerical simulation with CFD tool is carried out with RNG k − 𝜀 two-equation turbulence model based on Reynolds-averaged Navier–Stokes equations. To perform the coupling between rotating impeller and stationary area, the multiple reference frame (MRF) model is used. The numerical results of the fan are validated against with experimental results and are found to be highly reliable. The design and optimization of diffuser and impeller of a centrifugal fan are realized by using numerical investigations. For reducing the kinetic energy loss inside the fan, a guide baffle is added to optimize diffuser. The optimization results show that overall efficiency of the fan is improved by 5.27% and considering the lower efficiency of impeller caused by blockage at the blade inlet, etc., the design of impeller with long-short blades is proposed. Several cases of affecting factors under different operating conditions are simulated. Relative length (denoted as σ) and circumferential position of short blades are chosen as design variables. It is found that the efficiency of a fan with a relative length of 0.7 can be increased by 9.34%, and the best circumferential position of short blades is between two adjacent long blades. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the dynamics of the vortices in the homogeneous two-dimensional Bose–Einstein condensate by considering the condensate density variation. It is shown that the condensate density variation plays an important role when two vortices are close together. By the time-dependent Lagrangian functional method and the numerical simulation, we study how the interaction strength of the vortices varies with the distance between two vortices with the same or different topological charges, and generalize the results for the vortex pairs to the multi-vortex case. The numerical simulations demonstrate the validity of our theory. [ABSTRACT FROM AUTHOR]

In the modern society, most networked critical infrastructures are coupled together and can be modeled as interconnected networks. Cascading failures caused by overload in interconnected networks are extremely complicated and still lack of corresponding researches. It is crucial to explore a systematic design and load management method for complex interconnected network. In this paper, a probabilistic heterogeneous capacity allocation model and a preventive load redistribution model are firstly proposed. Based on the novel models failure cascades in interconnected networks are studied in detail. Numerical simulations and analysis results show that robustness of interconnected network depends on the network topology, capacity allocation pattern and load management strategy. The novel models have guiding significance for the design and optimal management of robust interconnected infrastructure networks. [ABSTRACT FROM AUTHOR]

In this paper, two important pseudo-parabolic type equations are studied for extracting soliton solutions via the generalized projective riccati equations method. These equations are Oskolkov equation and Oskolkov–Benjamin–Bona–Mahony–Burgers equation. The proposed method extracts dark soliton and singular soliton. Furthermore, the Painlevé test (P-test) has also been employed on pseudo-parabolic type equations for investigating integrability. The proposed equations are proved to be integrable by P-test. The numerical simulations have also been carried out by 3D and 2D graphs of some of the obtained solutions. [ABSTRACT FROM AUTHOR]

This paper explores effective seeding strategies in prisoner's dilemma game (PDG) on online social networks, i.e. the optimal strategy to obtain global cooperation with minimum cost. Three distinct seeding strategies are compared by performing computer simulations on real online social network datasets. Our finding suggests that degree centrality seeding outperforms other strategies regardless of the initial payoff setting or network size. Celebrities of online social networks play key roles in preserving cooperation. [ABSTRACT FROM AUTHOR]

In this paper, a new semi-discrete coupled system which was firstly proposed by Bronsard and Pelinovsky is under investigation. Based on its known Lax pair, the infinitely-many conservation laws and discrete N-fold DT for this system are constructed. As applications, bell-shaped multi-soliton and breather solutions in terms of determinants for this system are firstly derived by means of the discrete N-fold DT. Propagation and elastic interaction structures of such soliton solutions are shown graphically: (1) Propagation characteristics of one-, two-, three- and four-soliton solutions are discussed from vanishing background. (2) Propagation characteristics of one- and two-breather solutions are analyzed from the plane wave background. The details of the dynamical evolutions for such soliton and breather solutions are studied via numerical simulations. Numerical results show the accuracy of our numerical scheme and the stable evolutions of these solitons with or without a noise in a relatively short period of time, while the evolutions exhibit obviously larger oscillations and strong instability with the increase in time. These results may be useful for understanding the propagation of orthogonally polarized optical waves in an isotropic medium and circularly polarized few-cycle pulses in Kerr media described by the coupled NLS and coupled complex mKdV equations, respectively. [ABSTRACT FROM AUTHOR]

In this paper, the mean first-passage time (MFPT) in simplified FitzHugh–Nagumo (FHN) neural model driven by correlated multiplicative non-Gaussian noise and additive Gaussian white noise is studied. Firstly, using the path integral approach and the unified colored-noise approximation (UCNA), the analytical expression of the stationary probability distribution (SPD) is derived, and the validity of the approximation method employed in the derivation is checked by performing numerical simulation. Secondly, the expression of the MFPT of the system is obtained by applying the definition and the steepest-descent method. Finally, the effects of the multiplicative noise intensity D, the additive noise intensity Q, the noise correlation time τ , the cross-correlation strength λ and the non-Gaussian noise deviation parameter q on the MFPT are discussed. [ABSTRACT FROM AUTHOR]

In this paper, the nonlinear analysis of a viscous continuum traffic flow model is studied. The stability condition of the viscous continuum model is given by using the linear analysis method. The Korteweg–de Vries (KdV) equation is derived to describe the traffic jams. The effect of the viscous term is investigated by numerical simulations. The results show that the existence of the viscous term induces oscillation of traffic flow and the amplitude of the oscillation increases with increasing the coefficient of the viscous term. It is also found that the local clusters are compressed by increasing the coefficient of the viscous term. [ABSTRACT FROM AUTHOR]

In this paper, we study on dark solitons of Bose-Einstein condensate analytically in a time-dependent harmonic trap with an arbitrary time-dependent linear potential and complex potential. It is shown that the nonautonomous dark soliton can be manipulated well through managing external potentials and nonlinear interaction between atoms. We believe that these results would stimulate experiments to manage dark solitons. [ABSTRACT FROM AUTHOR]

In this paper, we study lump-kink solutions of a (2+1)-dimensional bidirectional Sawada–Kotera equation and discuss their dynamics. A Hirota bilinear form of a (2+1)-dimensional bidirectional Sawada–Kotera equation is deduced via a dependent logarithmic transformation. Based on this Hirota bilinear equation, we obtain eight classes of lump-kink solutions which combine stripe soliton and lump soliton by using symbolic computations. Our simulation results with the appropriate choice of the arbitrary parameters that show the motion of lump soliton and the process of interaction between lump soliton and a stripe soliton. [ABSTRACT FROM AUTHOR]

Under investigation in this paper are the three-coupled nonlinear Schrödinger (CNLS) equations, which govern the dynamics of solitonic excitations along three-spine α -helical protein with inhomogeneous effect. The vector periodic solitons (VPSs) of three-CNLS equations have been obtained by a transformation that transforms the corresponding equations to the integrable mixed three-CNLS equations. The VPSs getting from two-bright-one-dark solitons are different to the ones from two-dark-one-bright solitons. The latter propagates on periodic wave background and the interspine interaction coefficient adjusts the oscillation period. Moreover, the different-type VPSs are reported through manipulating external inhomogeneity potential. And it shows that VPSs can transform into bright–bright–bright solitons in the special conditions. Dynamic behaviors of those solitons are discussed through graphic simulation. [ABSTRACT FROM AUTHOR]

This paper constructs a new 4D chaotic system from the Sprott B system. The system is dissipative, chaotic with two saddle foci. The bifurcation diagrams verify that the system exists multiple attractors with different initial values, including two strange attractors, two periodic attractors. Furthermore, we apply the passive control to control the system. A controller is designed for driving the system to the origin. The simulations show our theoretical results visually. [ABSTRACT FROM AUTHOR]

This paper recommends a method to reduce harmonic distortion of MEMS accelerometer. The fifth-order MEMS accelerometer interface circuit designed in this work used the Cascade-of-Integrators, Feedforward modulation structure. This paper analyzes and calculates the main sources of HD, the unstable problem brought by the vacuum encapsulation sensitive structure. The use of front-phase compensation and the increase in loop forward gain helps ensure the system’s stability as well as reduce the system harmonic distortion. Simulink is used to get the simulation results. After harmonic optimization, the third harmonic reached −141.83 dB, the Signal-to-Noise-and-Distortion-Ratio rose to 118.1 dB, the noise density is under 200 ng/Hz 1 / 2 , the effective number of bits rose up to 19.33 bits. [ABSTRACT FROM AUTHOR]

This paper investigates the finite-time synchronization of complex networks (CNs) with non-identical nodes and impulsive disturbances. By utilizing stability theories, new 1-norm-based analytical techniques and suitable comparison, systems, several sufficient conditions are obtained to realize the synchronization goal in finite time. State feedback controllers with and without the sign function are designed. Results show that the controllers with sign function can reduce the conservativeness of control gains and the controllers without sign function can overcome the chattering phenomenon. Numerical simulations are offered to verify the effectiveness of the theoretical analysis. [ABSTRACT FROM AUTHOR]

In this paper, the effect of the speed limit on degradable networks with capacity restrictions and the forced flow is investigated. The link performance function considering the road capacity is proposed. Additionally, the probability density distribution and the cumulative distribution of link travel time are introduced in the degradable network. By the mean of distinguishing the value of the speed limit, four cases are discussed, respectively. Means and variances of link travel time and route one of the degradable road network are calculated. Besides, by the mean of performing numerical simulation experiments in a specific network, it is found that the speed limit strategy can reduce the travel time budget and mean travel time of link and route. Moreover, it reveals that the speed limit strategy can cut down variances of the travel time of networks to some extent. [ABSTRACT FROM AUTHOR]

It is important to realize good consistency among different device units on a big wafer. The bad product consistency results from the processing deviation which is hard to control. A novel simulation method to control and reduce the influence of processing deviation on the sensitivity of a piezoresistive pressure sensor is provided in this paper. Based on finite element analysis (FEA) and mathematical integration, the performance of the pressure sensors is simulated. The pressure sensors are designed and fabricated according to the simulation results. The test results confirm that this simulation method can help to design the pressure sensor very precisely. From the simulation and test results, we find that properly enlarging the size of the square silicon membrane can improve the devices consistency. [ABSTRACT FROM AUTHOR]

In this paper, a semi-discrete Brusselator system is considered. The Turing instability theory analysis will be given for the model, then Turing instability conditions can be deduced combining linearization method and inner product technique. A series of numerical simulations of the system are performed in the Turing instability region, various patterns such as square, labyrinthine, spotlike patterns, can be exhibited. The impact of the system parameters and diffusion coefficients on patterns can also observed visually. [ABSTRACT FROM AUTHOR]

In the absence of thermal fluctuations and other external forces, a single particle will be pinned at the bottom of a flashing ratchet potential under the overdamped condition. Unidirectional motion becomes possible if there exist interactions among particles. In this paper, the overdamped directed motion of a dimer with two heads in a flashing ratchet potential is investigated. We propose the mechanism to reveal how two heads of the dimer cooperate and help each other to move processively. The necessary condition of directed motion is analytically given, which is in good agreement with numerical simulation results. Furthermore, the resonant steps of the current are observed and discussed. The scenario and the results proposed in this paper may shed light on the elaborations of artificial molecular motors. [ABSTRACT FROM AUTHOR]

The evolutionary game on graphs provides a natural framework to investigate the cooperation behavior existing in natural and social society. In this paper, degree-based pinning control and random pinning control are introduced into the evolutionary prisoner's dilemma game on scale-free networks, and the effects of control mechanism and control cost on the evolution are studied. Numerical simulation shows that forcing some nodes to cooperate (defect) will increase (decrease) the frequency of cooperators. Compared with random pinning control, degree-based pinning control is more efficient, and degree-based pinning control costs less than random pinning control to achieve the same goal. Numerical results also reveal that the evolutionary time series is more stable under pinning control mechanisms, especially under the degree-based pinning control. [ABSTRACT FROM AUTHOR]

In this paper, two different kinds of methods are adopted to control Liu system — feedback method and nonfeedback method. On the one hand, direct feedback and adaptive time-delayed feedback are taken as examples for the study of feedback control. In the direct feedback method, Liu system can be stabilized at one equilibrium point or a limit cycle surrounding its equilibrium. In the adaptive time-delayed feedback method, feedback coefficient and delay time can be adjusted adaptively to stabilize Liu system at its original unstable periodic orbit. On the other hand, periodic parametric perturbation is used to control chaos in Liu system as a typical nonfeedback method. By changing the frequency of the perturbation signal, Liu system can be guided to not only periodic motion but also hyperchaos. Numerical simulations show the effectiveness of our methods. [ABSTRACT FROM AUTHOR]

Detonation process of a condensed explosive was simulated using a finite difference method. Euler equations were applied to describe the detonation flow field, an ignition and growth model for the chemical reaction and Jones-Wilkins-Lee (JWL) equations of state for the state of explosives and detonation products. Based on the simple mixture rule that assumes the reacting explosives to be a mixture of the reactant and product components, 1D and 2D codes were developed to simulate the detonation process of high explosive PBX9404. The numerical results are in good agreement with the experimental results, which demonstrates that the finite difference method, mixture rule and chemical reaction proposed in this paper are adequate and feasible. [ABSTRACT FROM AUTHOR]

Two dimensional hypersonic magnetohydrodynamics(MHD) flows with the chemical non-equilibrium effects are numerically simulated using upwind splitting scheme based on unstructured meshes. The governing equations are 2D MHD equations with the chemical components, where 5 species and 17 chemical reactions are considered. The AUSM scheme is implemented in the spatial discretization for the MHD equations, and an explicit 5-stage Runge-Kutta scheme is used for time integration. A loosely coupled approach is used to communicate between the MHD equations and the chemical reaction model. The computational model is a 2D blunt body, around which a dipole magnetic field is located. With hypersonic incoming flows, four different cases are numerically simulated to analyze the effects caused by the magnetic field and/or non-equilibrium chemical reactions. Numerical results are obtained and compared well with available data. [ABSTRACT FROM AUTHOR]

Based on volume of fluid (VOF) technique, the flapping motion of submerged turbulent plane jet in shallow water impinging vertically onto the free water surface was simulated. To study further on the flapping motion, the power spectrum density, the centerline velocity decay, as well as the mean velocity profiles of the jet were all investigated in this paper. The results are in great agreement with those of theoretical analyses, and the results show that the flapping motion is a new flow pattern of submerged turbulent plane jets. [ABSTRACT FROM AUTHOR]

In this paper, a three-dimensional (3D) randomly packed bed model is established to research the filtration combustion process. 3D numerical simulation of premixed combustion in the randomly packed bed is carried out, and the temperature distributions and flame propagation characteristics are predicted and discussed. Simulation results show that the change rules of the temperature field and the flame surface in the random model are consistent with the classical theory, and the stochastic packed model is more promising for numerical simulation of filtration combustion in comparison with the traditional regular structures. [ABSTRACT FROM AUTHOR]

In this paper, a modified microscopic traffic flow model accounting for the optimal velocity has been proposed. Different with previous models, drivers' response ability and the maximum of accelerations are considered in the term of the optimal velocity. The effect of parameters in the term of the optimal velocity on bifurcations in the rotary traffic is studied here. Besides, the evolvement of bifurcations in the system is calculated by performing numerical simulation experiments. Moreover, the linear stability analysis of the proposed model is presented. [ABSTRACT FROM AUTHOR]

Path planning is an essential and inevitable problem in robotics. Trapping in local minima and discontinuities often exist in local path planning. To overcome these drawbacks, this paper presents a smooth path planning algorithm based on modified visibility graph. This algorithm consists of three steps: (1) polygons are generated from detected obstacles; (2) a collision-free path is found by simultaneous visibility graph construction and path search by A (SVGA); (3) the path is smoothed by B-spline curves and particle swarm optimization (PSO). Simulation experiment results show the effectiveness of this algorithm, and a smooth path can be found fleetly. [ABSTRACT FROM AUTHOR]

A novel double driving signal line and driving electrodes separated radio frequency (RF) micro-electromechanical system (MEMS) switch was proposed in this paper to overcome the problems of the high actuation voltage, small displacement, and long pull-down time of the RF MEMS switches. Dynamic equations of the micro beam were built based on the small deflection theory. Dynamic behaviors of the proposed RF MEMS switch were analyzed and calculated by the variable separation method. The effects of different driving voltages, structure parameters and materials on the RF MEMS switch performance were discussed in detail. The simulation results presented that the proposed RF MEMS switch had an actuation voltage of 26 V, a pull-down time of 31.5 and an actuation displacement of 3 . The results also showed that the pull-down time of micro beam increased as the dielectric layer thickness increased. When the beam thickness was higher than 1.1 , the switch could not pull down anymore. Additionally, the switch had a lowest pull down time when Al was used as micro beam material, compared to Au, Si, and SiC. The COMSOL Multiphysics finite element analysis was carried out to validate the MATLAB simulation results, and the comparison results were basically consistent with the MATLAB simulation results. Besides, the proposed switch had an insertion loss of −0.2 dB on up-state and isolation of more than −20 dB on down-state at 60 GHz derived from the electromagnetic simulation results. The actuation voltage, pull-down time, actuation displacement, and electromagnetic performances of the proposed RF MEMS switch were compared to some other switches, which were better than some existing switches. [ABSTRACT FROM AUTHOR]

In recent paper, Nowak et al. report a charged wire interferometer for atoms, and employ analytical method to explain the interference patterns [ Phys. Rev. Lett. 81 (1998) 5792]. In this paper, a numerical calculation with semi-classical method is carried out and the experimental patterns are rebuilt very well. The interference patterns are interpreted by path integral. We also calculate the fringe period for different voltages and the agreement with experiment is more rigorous than the analytical expression. Besides, the fringe visibility of the interference patterns at different applied voltages and degrees is also discussed. [ABSTRACT FROM AUTHOR]

Classical statistical thermodynamics was developed in the second half of the 19th century. The implied fact is that since then all processes and effects that fall into the domain of classical statistical thermodynamics have been discovered and explained. However, analyzing the outputs from our numerical model of an ideal gas, we noticed that the atoms separate during the expansion of the gas into empty space. This separation occurs as a consequence of the distribution of molecules by velocities. Namely, faster molecules will move further away from their initial position than slower ones. The objective of this paper is to describe the existence of this process and to present some basic physical consequences of this effect. [ABSTRACT FROM AUTHOR]