Abstract:In this paper we propose Gauss-Jordan algorithm using column interchanges for computing a high-order dense matrix inverse produced by the high-order panel method in aerodynamics. The algorithm implements the block cyclic data distribution, which especially has communication advantages for the hypercube network. Results are achieved when running this program on the 4 SGI workstations configured as a 2×2 processor grid. It shows that 57%～64% efficiency can be gained when solving a matrix is about 1000 order.

Abstract:The quasi-one-dimensional vibrational-nonequilibrium nozzle flow of nitrogen gas is calculated numerically by using a time-dependent analysis. The explicit MacCormack scheme is used for the numerical solution. The vibrational-nonequilibrium effects of various flow parameters have been discussed and the important factor has been found. It is shown that for some practical nozzle conditions, the vibrational-nonequilibrium effects have significant influence on the freestream nozzle-flow properties.

Abstract:This paper presents an experimental study on the mixing characteristics of gas-liquid coaxial swirling injector of liquid rocket engine. A two-phase probe technique was employed to measure the distributions of gas and liquid mass flux and mixing ratio in sprays. The effects of the recess ratio of injector and the pressure drop of gas and liquid injection on the mixing characteristics were investigated. The results show that the recess ratio of injector plays a significant role in the mixing between gas and liquid flows from the coaxial swirling injector . Increasing the recess ratio will result in more uniform mixing between gas and liquid, and changing the pressure drop of injection will result in different distribution of mass flux and mixing ratio.

Abstract:Based on a coventional Extended Kalman Filter (EKF), a sub-optimal fading factor EKF is proposed in this paper, which can be used for the joint estimation of states and parameters of nonlinear time-varying stochastic systems. It is used for health monitoring in such a complex system as liquid rocket engine. Numerical simulation result shows the proposed estimator has better properties such as convergence, real time, and dynamic tracking ability etc. . In addition, some problems connected with the joint estimation and the applicability for real plants are also discussed.

Abstract:This paper gives the structural dynamic FEM model and corresponding FEM software package for a certain honeycomb sandwich composite satellite fairing. The natural frequencies and modes of the whole and half fairing under different boundary conditions are calculated. The separation behavior of half fairing and the load distribution in all binder blots subjected to aerodynamic load are analyzed.

Abstract:In this paper according to the equation of movement of the lunar module, under the condition of fixed thrust, the optimal direction of thrust is obtained. Along such a dirction, a self-adapting adjustment control is given to the perturbation equation to guarantee the stability of state-tracing, so as to assure the high precision of the output tracing state for the system under control.

Abstract:In this paper, we discuss the accuracy evaluation methods of guidance system and analyse a varieties of factors of affecting guidance accuracy. On the base of qualitative analysis, the error model of guidance system was established and was inducted to linear regression model. In the end, analysing and comparing many error detachment methods used at prescnt, the model reference adaptive generalized ridge estimation method is presented by model reference adaptive thought in combination with ridge estimation method. A efficient way is presented to solve the problem of guidance system error detachment.

Abstract:In the paper, vibro-acoustical load and time of pressure-vessel by vibro-acoustic ageing are investigated through the experiments on pressure-vessels and the control approach and criteria of the quality of vibro-acoustic ageing are obtained. The results of the application, the approach and criteria into the pressure-vessels are satisfying.

Abstract:In general, a threshold T is used to determin whether high-frequency wavelet coefficients to be insignificant in wavelet transforme coding of singals. That is, let x be a high-frequency wavelet coefficient, if |x|≤T, then x is insignificant and set x=0. In this paper, an optimum threshold T_opt is given theoretically and T_opt minmizes the average energy of the distortion between the original signal and the reconstructed signal.

Abstract:In this paper, an aircraft target automatic classifier based on real time recurrent neural network algorithm is proposed under the wide band fully polarized high range resolution radar. This new neural network classifier is applied to the classification of five types of aircraft targets. The result demonstrates the feasibility of using recurrent neural networks for aircraft target recognition.

Abstract:Based on the backscattering returns of high range resolution and full polarization radar, the Matrix Pencil method is proposed to describe the radar target as a set of scattering centers along its range. The concept of transient polarization response (TPR) is used to represent the full-polarimetric information of the scattering centers. Thus a new approach tor characterizing the target structure is developed.

Abstract:In this paper, we study the propagation property of the transient signals on the microstrip and taper microstrip liner using the method of the wavelet transform. This method has the advantages of fast compulating and localizing the wave form at any time and at any point along the transmission line to zoom compared with the conventional Fourier transform. We give the dispersion of the Gaussian signal and the rectangle pulse signals on the microstrip and the taper microstrip lines. The results can serve as referance in the study of the propagation of the ultra-high-speed and ultra-wide-band transient signals and in the design of MIC and MMIC.

Abstract:In view of fuzzy sets and their operations, three kinds of logical neurons, i, e. , AND, OR and AND/OR neurons can be chassified into two types: weighted and relational. Using AND, OR and AND/OR neurons, a fuzzy relational model for dynamic system modeling is provided as well as its learning algorithms. By a simple example, the soundness and learning capability of the algorithms are verified.

Abstract:First, this paper promotes the framework architecture of DIEMA. Then, we discuss the mechanism and executive of the DIEMA, and promote the implementation framework of Service agent and Request agent and their design and implementation.

Abstract:This paper presented a new, fast, and efficient quantization method for image compression with wavelet transform. This method combines the efficiency of Vector Quantization with the simple of Scalar Quantization. It needs neither training, nor multiplication.

Abstract:In this paper, a new method for edge checkout—Laser Half-focus locating method is introduced. Many comprehensive techniques have been used to ensure high precision of edge checkout, such as self adaptive tracking technique for compensation, laser modulating and modulated amplitude compensating technique, fixed point sampling technique through differential and fine dividing technique for step motor. A theoratical model for edge checkout using laser half-focus and its result of computer simulating are also given. In the end, a system of measuring diameter adopting this technology is described.

Abstract:The linear magnetic suspension model is used to design a variable structure controller with sliding mode, and realize this controller with a analog circuit. The results of simulation and experiment are presented.

Abstract:A new NC copying machining technique for non-circular piston ring is introduced, which makes it possible to work piston rings with different pressure distribution curve using a kind of cam, and realize error compensation while cam or cutting tool wears away. It improves the flexiblility and precision of machine. Moreover, the problem of disturbance resistance is resolved by an intelligent method of making policy combine with fuzzy control technology. It improves the system robustness, as well.

Abstract:For the linear analog circuits, a BIST method based on the system's state variables is presented. This method adds up the state variables, their variation speed and input signal by weights, uses the sum as the fault detection output of the system. The normal situation and abnormal situation can be distinguished by the magnitude of the output. This method is simple and reliable, and has a high fault coverage.

Abstract:F is a flat homomorphism from ring A to ring B. M is a A-module. We have obtained the inequation between id_AM and id_B(M○×_AB).

Abstract:Using the method of nonstandard analysis, we prove and generalize the theorem of Eberlein-Smulian, and obtain the equivalence of W-compact、W-coutably compact and W-sequentially compact in metrizable locally convex spaces.