The characteristics of nonlinear chaotic dynamics in quantum cellular neural networks

With the polarization of quantum-dot cell and quantum phase serving as state variables, this paper does both theoretical analysis and simulation for the complex nonlinear dynamical behaviour of a three-cell-coupled Quantum Cellular Neural Network （QCNN）, including equilibrium points, bifurcation and chaotic behaviour. Different phenomena, such as quasi-periodic, chaotic and hyper-chaotic states as well as bifurcations are revealed. The system＇s bifurcation and chaotic behaviour under the influence of the different coupling parameters are analysed. And it finds that the unbalanced cells coupled QCNN is easy to cause chaotic oscillation and the system response enters into chaotic state from quasi-periodic state by quasi-period bifurcation; however, the balanced cells coupled QCNN also can be chaotic when coupling parameters is in some region. Additionally, both the unbalanced and balanced cells coupled QCNNs can possess hyper-chaotic behaviour. It provides valuable information about QCNNs for future application in high-parallel signal processing and novel ultra-small chaotic generators.

Chaotic phenomena in Josephson circuits coupled quantum cellular neural networks

In this paper the nonlinear dynamical behaviour of a quantum cellular neural network （QCNN） by coupling Josephson circuits was investigated and it was shown that the QCNN using only two of them can cause the onset of chaotic oscillation. The theoretical analysis and simulation for the two Josephson-circuits-coupled QCNN have been done by using the amplitude and phase as state variables. The complex chaotic behaviours can be observed and then proved by calculating Lyapunov exponents. The study provides valuable information about QCNNs for future application in high-parallel signal processing and novel chaotic generators.

High Power Fiber Bundle Array Coupled LDA Module

An optical fiber bundle array coupling module with high output power is presented in this paper. The device integrated the coupling technique of the high power laser diode array (LDA) and the micro-ball lenses fiber array. This module can efficiently couple the output laser of the LDA into 19 fibers array with micro-ball lens end-surface. The difference of the couple efficiency between the flat-end fiber and micro-ball-end fiber is discussed. The micro-ball lenses fiber array made of 19 fibers have the same fiber core diameter of 200 m, and then the end-surfaces of 19 fibers are fused to 19 micro-ball lenses. The micro-ball lenses fiber array are fixed precisely in the neighborhood on the V-grooves, and the fiber array has the same arrange period with the semiconductor laser units of LDA. This configuration of micro-ball lens fiber array can greatly reduce the divergence of the laser beam from all directions, and a very efficient laser beam homogenizer and shaper are obtained. Finally, high output power of 30.1 W of the fiber coupled LDA is achieved, and the maximal coupling efficiency is >83% with the numeral aperture (NA) of 0.16.

Thermodynamics and Kinetics Study on Improving the Microstructure of High Chromium Cast Iron by Multi-Alloying

The effects of multi-alloyings(V,Ti and Nb)on carbides precipitation and as-cast microstructure of eutectic high chromium cast iron containing 2.8 wt.%carbon and 31.0wt.%chromium were investigated.The results showed that with the increase in the amount of alloy elements,the cast microstructure of 2.8C-31Cr high chromium cast iron changed gradually from refinement to coarsening and the total volume fraction of carbides decreased.When the addition of alloy was0.4V-0.40Ti-0.40Nb-0.35Mo,the solidification microstructure was largely improved,the distribution of carbides was reasonably uniform.The existence form of strong carbides forming elements(V,Ti,Nb)and the reasons of rnicrostructure change were investigated from thermodynamics and kinetics considerations.

Effect of Sn precursor on the synthesis of SnO2 and Sb-doped SnO2 particles via polymeric precursor method

SnO2 and Sb-doped SnO2 particles were synthesized using the polymeric precursor method with different Sn salt precursors： SnCl2.2H2O, SnCl4.5H20, or Sn citrate. Sb2O3 was used as the precursor of Sb, and the molar ratio of nsn：nsb was held constant. FTIR and TGA/DTA were used to examine the influence of the Sn precursor on the formation and thermal decomposition of the Sn and Sn-Sb complexes. The calcination products obtained from heating the Sn and Sn-Sb complexes at 500℃ in air were analyzed using XRD and TEM analysis. The results revealed that the SnO2 and Sb-doped SnO2 formation temperatures depended on the nature of the Sn precursor. The calcination products were found to be SnO2 and Sb-doped SnO2 particles, which crystallized in a tetragonal cassiterite structure with a highly preferred （110） planar orientation. The Sn precursor and the presence of Sb in the SnO2 matrix strongly influenced the crystallinity and lattice parameters.