Symmetry of Lagrangians of nonholonomic systems of non-Chetaev’s type

This paper studies the symmetry of Lagrangians of nonholonomic systems of non-Chetaev's type. First, the definition and the criterion of the symmetry of the system are given. Secondly, it obtains the condition under which there exists a conserved quantity and the form of the conserved quantity. Finally, an example is shown to illustrate the application of the result.     

Normalized entropy of rank distribution： a novel measure of heterogeneity of complex networks

Many unique properties of complex networks result from heterogeneity. The measure and analysis of heterogeneity are important and desirable to the research of the properties and functions of complex networks. In this paper, the rank distribution is proposed as a new statistic feature of complex networks. Based on the rank distribution, a novel measure of the heterogeneity called a normalized entropy of rank distribution (NERD) is proposed. The NERD accords with the normal meaning of heterogeneity within the context of complex networks compared with conventional measures. The heterogeneity of scale-free networks is studied using the NERD. It is shown that scale-free networks become more heterogeneous as the scaling exponent decreases and the NERD of scale-free networks is independent of the number of vertices, which indicates that the NERD is a suitable and effective measure of heterogeneity for networks with different sizes.     

Analysis of sound radiation characteristics of complex double shells

The double stiffened shell connected by annular plates is systematically studied.The shell motion is obtained using the classical Fliigge operator, the effects of stiffeners are induced into the vibration equation by treating them as reverse included in forces and moments on the shell, and the fluid field between the inner shell and outer shell is solved by applying Helmholtz equation and the continuity conditions of the displacement on the surface of fluidstructure. At last the vibration equation coupled by the sound-fluid-structure are constituted and solved. The effects of the double shell parameters and linked types between the double shells on the sound radiation are discussed in detail. The following conclusions can be gotten:The smaller the space between the inner shell and outer shell, the stronger the coupling of the inner shell and outer shell, the higher the radiated power and radial quadratic velocity, and the more indistinct the shield of the outer shell. The changes of the thickness of the inner shell and outer shell influenced the radial quadratic velocity greatly, and influenced the radiated power indistinctly. The thicker the thickness, the lower the radial quadratic velocity.     

Effects of Magnetic Coupling on Profile of Emission Lines and Images of an Accretion Disc Around a Black Hole

The profiles of emission lines and images of an accretion disc around a black hole (13tt) are simulated by considering the effects of the magnetic coupling (MC) of a central BH with the disc. The MC effects are discussed for both slow- and fast-spinning BHs, and the following results are obtained. Firstly, the width of the emission lines and the brightness of the disc are reduced and augmented for slow- and fast-spinning BHs, respectively. Secondly,the image of the disc becomes dimmer and brighter near the inner edge of the disc for slow- and fast-spinning BHs, respectively. It turns out that all these results arise from the MC effects on the position of the dominant emission region of the accretion disc.     

Characteristics of titanium oxide memristor with coexistence of dopant drift and a tunnel barrier

The recent published experimental data of titanium oxide memristor devices which are tested under the same experi- mental conditions exhibit the strange instability and complexity of these devices. Such undesired characteristics preclude the understanding of the device conductive processes and the memristor-based practical applications. The possibility of the coexistence of dopant drift and tunnel barrier conduction in a memristor provides preliminary explanations for the undesired characteristics. However, current research lacks detailed discussion about the coexistence case. In this paper, dopant drift and tunnel barrier-based theories are first analyzed for studying the relations between parameters and physical variables which affect characteristics of mernristors, and then the influences of each parameter change on the conductive behaviors in the single and coexistence cases of the two mechanisms are simulated and discussed respectively. The simulation results provide further explanations of the complex device conduction. Theoretical methods of eliminating or reducing the coex- istence of the two mechanisms are proposed, in order to increase the stability of the device conduction. This work also provides the support for optimizing the fabrications of memristor devices with excellent performance.     

Influence of Combination of Casimir Force and Residual Stress on the Behaviour of Micro-and Nano-Electromechanical Systems

Casimir force and residual stresses actually appear in over-layers or films simultaneously.The study of the behaviour of micro-and nano-electromechanical systems in the presence of Casimir force and residual stress is of significance to the design of the relevant devices.We derive analytical expression of the deflection of a bridge-shaped device under the mutual actions of Casimir force and residual stress in films.It is shown that the tensile residual stress enhances wavy behaviour of the deflection,while the compressive residual stress increases the deflection value and reduces the wavy behaviour.     

Solution of the level of approximation analytic formula of hydrogen-like atom for the Debye shielding potential by means of the power series

The first-order revision and the approximation analytical formula of the energy levels for hydrogen-like atoms in condition of the Debye shielding potential are achieved by means of the Rayleigh Schrdinger perturbation theory and the power series;meanwhile,the corresponding recurrence relations are got with the use of the solution of power series.Basic on mentioned above and with the use of energy consistent method,the equivalent value of second-order revision in condition of the Debye shielding potential as well be got and the result is compared with the data obtained by the numerical method.Beside,the critical bond-state and corresponding cut off of conditions are discussed.     

Direct Measurement of Squeezing in the Motion of Trapped Ions

We present a simple method that can be used to directly measure the squeezing of the quantum motional states of a trapped ion. Through the use of the interaction between the trapped ion and classical lasers, one can design a required coupling between the internal electronic and external vibrational degrees of freedom of the ion and can transfer information of the expectation value of a vibrational operator to the atomic internal populations. Thus measurement of squeezing on the quantum motional state can directly be realized. By adjusting the phases of the interacting lasers, one can measure the squeezing of both position and momentum quadratures.     

Inverse problem of the scattering of a finite-length cylinder

Dealing with the direct problem of target scattering,the geomet-rical theory of diffraction and resonance scattering theory are used tostudy the scattering of an elastic cylinder,the results of which are appliedto solve the inverse problem.Using the geometrical theory of diffraction,the relations between the geometrical parameters of cylinder and thediffracted signals have been found,meanwhile the connexions between thephysical parameters of cylinder(i.e.the longitudinal velocity,transverse velocity and density of the material consisting of the cylinder)and the internal resonances of the cylinder have been shown by means ofthe resonance scattering theory.Therefore in the present artical an availa-ble method for solving the inverse scattering of cylinder is provided.     

Effect of C60 nanoparticles on elasticity of small unilamellar vesicles composed of DPPC bilayers

The interaction between C60 nanoparticles and biomembranes has been of great interest in researches over the past decades due to their novel applications as well as potential cytotoxicity.In this work,we study the deformation of the small unilamellar vesicles composed of dipalmitoylphosphatidylcholine(DPPC)lipid bilayers infiltrated with C60 nanoparticles of different molecular concentrations through coarse-grained molecular dynamics simulations.By employing the Helfrich spontaneous curvature model,the bending modulus and the spontaneous curvature of the vesicles with C60 nanoparticles of different concentrations are obtained according to the simulation data.The results show that the bending modulus and the spontaneous curvature of pure DPPC vesicle membranes are approximately 1.6×10^-19J and 1.4 nm^-1,respectively.Both of them increase linearly approximately as the C60 concentration increases from 0 to 16.3%.The density profiles of vesicles,the order of lipid packing and the diffusion characteristics of DPPC and C60 are also investigated.     

Optimization of robustness of network controllability against malicious attacks

As the controllability of complex networks has attracted much attention recently, how to design and optimize the robustness of network controllability has become a common and urgent problem in the engineering field. In this work, we propose a method that modifies any given network with strict structural perturbation to effectively enhance its robustness against malicious attacks, called dynamic optimization of controllability. Unlike other structural perturbations, the strict perturbation only swaps the links and keeps the in- and out-degree unchanged. A series of extensive experiments show that the robustness of controllability and connectivity can be improved dramatically. Furthermore, the effectiveness of our method is explained from the views of underlying structure. The analysis results indicate that the optimization algorithm makes networks more homogenous and assortative.     

Geodesics of Spherical Dilaton Spacetimes

The properties of spherical dilaton black hole spacetimes are investigated through a study of their geodesics. The closed and non-closed orbits of test particles are analysed using the effective potential and phase-plane method. The stability and types of orbits are determined in terms of the energy and angular momentum of the test particles. The conditions of the existence of circular orbits for a spherical dilaton spacetime with an arbitrary dilaton coupling constant α are obtained. The properties of the orbits and in particular the position of the innermost stable circular orbit are compared to those of the Reissner-Nordstrom spacetime. The circumferential radius of innermost stable circular orbit and the corresponding angular momentum of the test particles increase for α≠ 0.     

Theoretical Calculation of Energy Spectrum of YGG：Cr^3＋ and Thermal Shifts of Its R-Lines

With the strong-field scheme and trigonal bases, the complete d3 energy matrix in a trigonally distorted cubic-field has been constructed. By diagonalizing this matrix, the energy spectrum of YGG：Cr^3＋ at normal pressure and low temperature has been calculated. The g factor of the ground-state has been evaluated in terms of the energy spectrum. At the same time, by using the wavefunctions obtained from diagonalizing the complete d^3 energy matrix and Thermal Shifts theory, we calculate the thermal shifts of the sharp lines of YGG：Cr^3＋ and determine the relevant parameters. The calculated results are all in good agreement with the optical-spectrum and EPR experimental data. It is demonstrated that the obtained wavefunctions and the values of parameters are reasonable.     

Form invariance and Lie symmetry of equations of non—holonomic systems

In this paper,we study the relation between the form invariance and Lie symmetry of non-holonomic systems.Firstly,we give the definitions and criteria of the form invariance and Lie symmetry in the systems.Next,their relation is deduced.We show that the structure equation and conserved quantity of the form invariance and Lie symmetry of non-holonomic systems have the same form.Finally,we give an example to illustrate the application of the result.     

Tuning of the cosmic-ray test system of the BESⅢ drift chamber

The BESⅢ drift chamber and its subsystems need a cosmic-ray test after the chamber construction to check the chamber construction quality,testing the joint operation of the whole system and the performance of the chamber.The noise performance,drift time and charge measurements,and the scanning of channels were examined specifically.The preliminary results of the test indicate that the whole system works well.     

Beam transmission efficiency of the HIRFL-SSC

In this paper we address the problem of the low beam transmission efficiency of the HIRFL-SSC. The influence of the SFC-SSC energy match, the SSC RF voltage, and harmonic field in the injection area of the SSC, and the SSC central trajectory on the beam transmission efficiency have been analyzed both from the theoretical side and from the actual operating data. The main reason is that the soft-edge approximation of the magnet field (the so-called theoretical field) and the simplified calculation programs were adopted when calculating the beam center trajectory and designing the injection and extraction system, and the measured magnetic field was not used to correct the calculation results. These led to large deviations of the calculated center trajectory, and then resulted in low efficiency of the SSC beam transmission. Therefore, the re-calculation of SSC beam center trajectory and injection and extraction system, as well as the measured magnet field correction are the key points required to solve the problem.     

The equivalent circuit of ultrasonic coupling vibration of a longitudinally-excited short column

On the basis of apparent elasticity method,we derived the equiva-lent circuit of coupling vibration of a short column and discussed its frequencyequation and the effects of the load impedance on the resonant frequency of theshort column.By the equivalent circuit,we calculated the input mechanicalimpedance of the longitudinally-excited short column and the curves of the ap-parent vibration velocity ratio versus the geometrical dimensions of the column.It shows that the equivalent circuit method is a simple and convenient one toanalyze and calculate the coupling vibration of the short column.     

Measurements of Absorption and Anisotropy Coefficients of the Fat Emulsion Intralipid-10%

We report measurements of absorption and anisotropy coefficients of the fat emulsion Intralipid-10%. An addingabsorber method is used for measurement of absorption and anisotropy coefficients of the Intralipid-10%. Using the diffusion theory which has been extended to include anisotropy scat geometry, we found that the standard deviations of multiple measurements for√μα/D are less than 0.6% and the residuals between the measured data and the fits have rms values of 0.1%, where μα is the absorbing coefficient of the solution in our experiment and D is the diffusion coefficient of the medium. The values of the standard deviations and the residuals demonstrate the high precision of the measurements.