Since a chaotic attractor can be reconstructed with time-delay embedding method in dissipative chaotic systems, there are potential problems in chaos-based information encryption. Concerning this issue, we report a conservative-chaos-based key distribution protocol and image encryption algorithm. The encryption algorithm converts image data into initial value of a conservative chaotic system with Hash algorithm and forms an encryption mechanism of one-time pads. Then, a binary keystream is generated by combining conservative chaos with key distribution protocol, which is completed by both sender and receiver. The obtained binary keystream shuffles and diffuses the image data to obtain an encrypted image. It shows that the proposed algorithm is safe and reliable. It hides effectively a plain image, and resists common decryption algorithms. Besides, conservative chaos has no attractor thus the encryption algorithm is hard to crack.

Influence of pulse width, laser wavelength and laser intensity on state populations of a NaI molecule driven by a pump-probe pulse was studied via time-dependent wave packet approach.Wave packet moves periodically with roundtrip time 1 000 fs.Wave packet bifurcates in crossing region firstly at delay time 200 fs, which affects state populations.Excitation probability increases and dissociation probability decreases with increasing pulse width.Excitation probability approaches the maximum at resonance pump wavelength 318 nm.Dissociation probability decreases with increasing pump wavelength.As pump intensity increases, excitation probability increases while dissociation probability does not change.Probe wavelength and probe intensity do not affect state populations.Wave packet motion and selective distribution of state populations can be achieved by adjusting laser parameters.It provides bases for realizing light manipulation of molecules experimentally.

Autler-Townes (AT) splitting in photoelectron spectra of four-level ladder K₂ molecule driven by three laser pulses is investigated with time-dependent wave packet approach. Dependence of AT splitting on second laser pulse is studied. Photoelectron spectra show triple splitting with symmetric profiles in resonance, while triple splitting with asymmetric profiles is transformed into double splitting gradually in nonresnance. Three peaks shift to lower energy differently as laser wavelength increases. Splitting between two sideband peaks does not vary with laser wavelength, but increases with increasing laser intensity. These results are of importance for molecular spectroscopy. It stimulates theoretical studies from first principles and provides basis for realizing optical control of molecules.

Large eddy simulation (LES) with 1.12×108 meshes was performed on three-dimensional jet in cross-flow(JICF) using lattice Boltzmann method (LBM) and multiple Graphic Processing Units (Multi-GPUs). Reynolds number based on free-stream velocity and jet diameter is 4 000, streamwise inclination angle of jet is α=30°, and jet-to-cross-flow velocity ratio is set as 0.5. Validity and feasibility of LBM-LES on simulating jet in cross-flow were verified by reasonable qualitative and quantitative results. Fine coherent structures were captured by large-scaled simulation which benefits study on mixing mechanism of jet-in-cross-flow(JICF). Moreover, 6 K20M GPUs were adopted in simulation and it took 15 402 seconds for LBM-GPU solver to simulate 71 680 LBM steps resulting in calculated performance of 521. 24 MLUPS.

Based on interconnection transmission differential equation,transform voltage and current expressions are derived by incorporating appropriate boundary conditions for interconnect energy analysis.We considered a practical transmission line with driver and load to find out relation between transform input and output voltage and current responses.Interconnection energy distribution is obtained,which considers non-ideal step stimulation.In 65 nm CMOS process,the non-uniform interconnect analytic model enables to estimate energy within 5% compared with Hspice simulations.The method has high accuracy.The analytic model can be applied to front end optimizing design and analysis of high performance global interconnection.

A power consumption equation of MCM (Multi-Chip Module) interconnect is presented in an S-domain RLC transmission line model. Simulation results are shown to verify the theoretical analysis.

The electron transport properties in 2H-,4H-,and 6H-Silicon Carbide are investigated numerically with an ensemble Monte Carlo technique.The acoustic phonon deformation potential scattering,polar optical phonon scattering,intervalley phonon deformation scattering,ionized impurity scattering and neutral impurity scattering are considered.The electron mobilities of 2H-,4H-,and 6H-SiC as a function of temperature at low electric field are obtained.The influence of the neutral impurity scattering on the transport property of 4H-SiC is discussed in detail.Finally,the static and transient variation of electron drift velocity in high electric fields are studied.The peak transient velocity in an electricfield of 1.0×10⁶ V·cm^-1 is 3.3×10⁷cm·s~(-1) for 4H-Sic and 3.0×10⁷ cm·s^-1 for 6H-Sic when the electric field is applied perpendicular to the c axis.The simulated results are in good agreement with recent experiments in a wide range of temperature and electric field.

The electron structure of the Na_1/2Bi_1/2TiO₃ system with ABO₃ type perovskite structure is studied by using self-consult charge-discrete variation-X_α (SCC-DV-X_α) method, and the effect of A, B position substitute on poling characteristic is also analyzed. The calculational results show that spontaneous polarization exists in the NBT piezoceramics system, the piezoelectric properties are enhanced because of the displacement of the B position ions, in addition, the compound substituent of Ba, Sr and Mn ion can decrease coercive field, and increase the strength of spontaneous polarization, so the dielectric properties get improved.

The corrected Gramm-Schmidt method is employed in 3-splined fitting of photoionization cross sections which was calculated in the authors previous work.In the case of LTE approximation,photon and free electron are assumed to be in Planck and Maxwell distribution respectively.The present derivation shows that,the rate coefficients of photoionization and radiative recombination can be described analytically in terms of 3-splined fitting parameters.This formulation is applied to He-like Rb and He-like Nb ions,and some of the results are figured out and analysed.By means of averaging over initial states and summing over final states,the degeneration of rate coefficients that concern the level level transitions is analysed explicitely.With the attained result, comparison and evaluation have been made to the formula given by reference[1].

The GRASP program based on the multi-configuration Dirac-Fock self-consistent method have been extended and revised, so 15 configurations which consist of 89 energy levels in Ne-like titanium ions can be calculated in the same self-consistent process.In the calculations, the averaged level (AL) model and the Fermi two-parameter distribution model of the nuclear volume effect are considered, also Breit correction, vacuum polarization and self-energy effect are counted. LS and jj coupling labels are determined by the maximum combination coefficients. Electric dipole, electric quadrupole and magnetic dipole transition probabilities and oscillator strengths are calculated. The results of oscillator strengths are given in both the Coulomb and the Babushkin gauge, and the electro-dipole oscillator strengths in Babushkin gauge are also compared with the nonrelativistic counterpart.