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The stability and reliability of electrical ohmic contacts are the key to the stable operation of silicon carbide power electronic devices in extreme environments. Firstly, the current research status and common problems of SiC ohmic contacts has been analyzed. Secondly, a carrier model for the ohmic contact between metals and SiC based on the tunneling effect is established. By increasing the doping concentration of the substrate SiC, the Schottky barrier width can be reduced, which is more conducive to the formation of ohmic contacts. Thirdly, 200nm thick Ni metal layer was deposited on 4H-SiC substrate with a doping concentration of NA=2e19cm-3. Finally, the effect of high-temperature thermal annealing temperature on metal ohmic contact is studied and results show that Ni can form ohmic contact with SiC when the annealing temperature exceeds 800°C. Scanning electron microscope and atomic force microscope are used to observe the contact surface. After high-temperature thermal annealing, the electrical properties are guaranteed, but metals indicate defects such as cluster precipitation. Therefore, it is possible to prevent the contact layer metal from being damaged by adding other covering metals.

With the integration of integrated circuits continues to rise, the feature size of integrated devices has entered nanometer. Single electron transistor (SET) is satisfied as nanoelectronic devices, and the SET will be mixed with the composition of nano-MOS devices (SETMOS), is one of the hot current study. SETMOS as a new hybrid device combine the advantages of both, it also has the same Coulomb oscillation characteristics with the SET and MOS high gain. Integrated analog signal processing filters as the basic unit circuit, it must conform to the development of the times. Based on the I-V characteristics of a SETMOS hybrid device model, a SETMOS integrator is designed, and expounding it's the operating condition, structure, performance, parameter and characteristics. The transmission performance of the integrator designed is simulated by SPICE. The conclusion is proved by simulation result.

Ore recovery depends on the stope structure parameters, at the same time, stope safety will be changed according to difference stope structure parameters. A mechanics model of stope structure of room and pillar mining method is established with FLAC3D, a finite difference software, in this paper. And the stope stability changing with crustal stress and stope structure parameters is simulated. The results of numerical simulation indicate that when mining level orebody with room and pillar mining method, tensile stress in central roof linearly decreases along with the increase of lateral pressure coefficient, and the influence of lateral pressure to tensile stress in roof near the pillar is obvious. The roof's maximum tensile stress and pillar's average vertical stress are increased with the increase of vertical stress, which makes the safety of stope decreased. And the roof's maximum tensile stress is hardly changed with the pillar height; but increased with the increase of room span. So it can be seen that the roof's stability can be improved by increasing the pillar size.

According to the non-stationary feature of ECG signal, a new classification method of arrhythmia is introduced. This method combines empirical mode decomposition (EMD) with singular value decomposition (SVD), using support vector machines (SVM) for classifying. First, ECG signal is decomposed into a set of intrinsic mode function (IMF) using empirical mode decomposition method. The initial feature vector matrix is formed by these IMFs. Then, the initial feature vector matrix is decomposed using singular value decomposition, and singular values of the matrix can be calculated. Singular values are regarded as the feature vector of ECG signal, support vector machines used as classifiers are established to identify the condition of arrhythmia. Experimental results show that, this method can classify the types of arrhythmia accurately and effectively, and can be used for the field of ECG pathological auxiliary diagnosis.

This paper studies an adaptive fuzzy control problem for a class of uncertain nonlinear systems in the pure-feedback form. Compared with the existing approaches, the two main advantages are that the proposed algorithm can be implemented by utilizing only one fuzzy logic systems (FLS) approximator and the robustness of the closed-loop system is improved. The proposed adaptive fuzzy control algorithm can guarantee that all the signals of the closed-loop system are uniformly bounded and the tracking errors converge to an arbitrary small neighborhood around zero. The feasibility of the proposed algorithm is obtained by a simulation example.

Based on the tracking control of chaotic system, the synchronization of hyperchaos in three-cell coupled quantum cellular neural network is studied; a secure communication system based on the hyperchaotic synchronization of the quantum cellular neural network is presented; its performance in the presence of channel noise is analyzed. Numerical simulations are given to illustrate the effectiveness of the hyperchaotic synchronization and secure communication. It is more secure due to the use of hyperchaos.

A nonlinear feedback controller is designed to make the first two state of a chaotic system called Josephson-circuits-coupled quantum cellular neural network track an arbitrary two-dimensional smooth reference signal. It is proved by means of Lyapunov function that this method can make the system approach to any two desired smooth orbits at an exponent rate. The synchronizations with Duffingpsilas chaotic system and Rosslerpsilas chaotic system are also presented. Numerical simulations are made to verify the results.

An implementation method of cellular neural networks (CNN) based on a novel complimentary metal-oxide-semiconductor (CMOS) and single electron transistor (SET) hybrid structure named SETMOS, is proposed in this paper. The main building blocks including cell core circuit, feedback template and control template circuits are designed by the characteristic of negative differential resistance (NDR) of SETMOS and current mirror. Finally, a CNN is constructed and applied in image processing on connected component detector (CCD) and shadow detector (SD). The computer simulation results show that the designed SETMOS CNN circuits, compared to traditional CNN hardware circuits, are suitable for various scale CNN implementation because of simpler structure, lower power dissipation, faster response and higher integrated density. To a certain degree, this kind of designed structure makes it practicability and reliability in image processing.

This paper present a circuit design of a 8-bit parity code generator using single-electron transistors (SETs). The design is based on the characteristic of multigate single-electron transistor and a single-electron transistor can realize a n-input exclusive-OR (XOR) gate or XNOR gate. The proposed design enable us to construct a 8-bit parity code generator using only four SETs. The simulation is performed with the circuit simulator PSpice, where the MIB model.

With the polarization of quantum-dot cell and quantum phase serving as state variables, both theoretical analysis and simulation are made of the complex chaotic dynamical behavior of a three-cell-coupled Quantum Cellular Neural Network, including equilibrium points, Lyapunov exponents and Poincare maps. As a result, equilibrium points are obtained and found to be symmetric and periodic; three of the six Lyapunov exponents are found positive; the Poincare maps composed of a large number of thick dots which are distributed over a certain curve. The latter two items prove the chaotic behavior of this system.