Abstract:The implicit varied coefficient residual smoothing technology was introduced into the four-stage Runge-Kutta scheme to increase the computational efficiency for unsteady supersonic flow under keeping second order accuracy in time and space. The computational results achieved by four-stage Runge-Kutta scheme and dual-time method were compared through numerical simulation unsteady harmonic oscillating flow around sphere-cone.

Abstract:A new algorithm based on genetic algorithm is formulated to ambiguity resolution. Integer Gauss transformation is used to reduce correction, then integer ambiguity is searched for in transformed space using genetic algorithm. Two mutation operators are used to avoid early convergence in the condition of small population size. Simulation shows the new algorithm is more robust and efficienct compare with SGA.

Abstract:The transfer function method is combined with the traditional spectral approach theory. The stochastic field is expanded by orthonormal Karhunen-Loeve method, the static stochastic beam analyzed and its credibility reckoned in the end. This method conquer the difficulty of the huge numerical computation of the traditional finite element method and an analytical analysis method of stochastic structure analysis is formed.

Abstract:A finite volume method is used to simulate the shock train flows in a generic two-dimensional constant area isolator. Isolator is an important components of Dual-Mode scramjet. The interaction between a normal shock wave and a boundary layer along a wall surface in isolator compressible flows causes a very complicated flow. The interaction region including a shock train and a mixing region in it is referred to as “pseudo-shock”. The finite volume method is used to solve the 2D Reynolds-averaged Navier-Stokes equation coupling the Baldwin-Lomax zero-equation turbulence model. In the numerical procedure, LUSGS method and TVD scheme are used. The numerical results simulate commendably the topology structure of the flows.

Abstract:The effects of different high temperature air models on electron density in the plasma sheath of the reentry capsule are studied, including the comparison between chemical non-equilibrium model and thermochemical non-equilibrium model, as well as that between 7 species model and 11 species model. The NND scheme and time preconditioning technique is applied to solve the full Navier-Stokes equations of non-equilibrium flow. Typical results of electron denstiy in the plasma sheath are obtained. The numerical results are good compared with the flight measurement and other numerical results.

Abstract:Because the target transmissivity (reflectivity) must be determined in advance in any conventional wideband monitoring of optical film thickness, this paper puts forward an imagination of mapping out parameters of film thickness and dispersive coefficients (refractive index) and continuously modifying target transmissivity in a coating time, by which the defect of the conventional wideband monitoring of optical film thickness can be overcome. The system of wideband monitoring of optical film thickness based on modifying target transmisivity has been built up. Its construction and working theory have been discussed. The accuracy of transmissivity measured by the system is higher than 2‰. A series of experiments of monitoring film thickness have been accomplished. It has shown that the accuracy of monitoring by the system is higher, the repeatability is better, and the accuracy of judging the end of coating is higher than1%.

Abstract:Supported Co ultrafine partical catalysts were prepared by means of sol-gel methods and supercritical drying. Their catalytic performance for CO oxidation was studied. The results indicate that the catalysts have high activity even with low content (1%～2%). They show good heat stability and can be performed in a wide reaction temperature area ranging from 160℃ to 800℃ .With the increase of Co Concentration, the activity and stability of Co-SiO₂ increase.

Abstract:A new fault detection method is proposed for the integrated navigation system. Fault detection is undertaken by checking the consistency between the global state estimate and the local state estimate of federated filter by means of the chi-square test (CST). Meanwhile, the fault isolation method is also discussed. The simulation and laboratory experimental results show that the new method is very efficient and practical; the reliability and safety of the system can be improved.

Abstract:On the basis of the characteristics of the Duffing equation's solutions, the chaotic oscillators are designed. This kind of oscillators can present the properties of sensitive dependence on weak signal and immunity to noise, so they can be used to detect the weak signals. This method can also be used in early detecting rub-impact fault of rotor system. The result shows that this method is simple and feasible.

Abstract:A parallel x-y manipulator system for an epoxy writing application is developed. The best advantage of the system is a significant reduction in size of the present epoxy writing system. The other primary advantage is to increase rigidity of the parallel mechanism, thus ensur faster operation with higher accuracy and improved tracking performance. It shows that the tracking error is smaller than 0.5mm.

Abstract:A system for auto building processing tables is presented to meet the need of the application of CAPP in enterprises.An universal model is built to deal with the processing tables,which takes the processing table of an enterprise as an instance and accordingly takes its types and requirements etc.as the properties of the above instance.The system adopts ODBC technology in order to offer an interface to interchange data among different systems such as MIS,PDM.It is proved that the system is of originality universality and practicability.

Abstract:The phase error of UWBR(Ultra_{_}WideBand Radar) system based on LFM signal, will affect the result of the pulse compression of the radar system. The phase gradient algorithm presented in this paper can estimate the phase error of the system effectively, and improve the performance of the pulse compression.

Abstract:The bottom function-realizing module is a key part of the Common Design Platform(CDP) of Multimedia Simulation and Training System(MSTS) for the Stored Program Controlled Telephone Exchange(SPCTE). Hardware configuration is the foundation of the SPCTE, the important part of the bottom function-realizing module. The modeling of the hardware of the SPCTE is proposed. Two typical SPCTE are used to explain and verify the models. The application of the models in the CDP is also given.

Abstract:Several existed models for scalability analysis are introduced. The time-constraint and memory-constraint speedup laws are analyzed from a new viewpoint. Based on these models, we extract the essential of this metric and give a generalized definition for it when the parallel system is composed of a parallel algorithm and an isomorphic architecture. From this definition, present three other models for scalability analysis: equal-average-I/O-requirements model, equal-average-communication-requirements model and equal-utilization model. Finally, We discuss the extension of these models to cluster of workstation systems.

Abstract:Two-step algorithm is proposed for unsupervised detection of linear structure from SAR image, in particular, the road network detection. The first step is to detect line element with local detector, in this paper an improved ratio of average (RoA) detector which takes into account the inner statistic property of SAR image is proposed. It can guarantee the detection accuracy. In the second step, we introduce the prior knowledge about the road structure to group the line element into macroscopical structure. The method proposed is identified in ERS-1 image.

Abstract:In the high level synthesis of application-specific DSP, pipeline scheduling is a difficult and urgent problem. In this paper the theory of normalized scheduled data flow graph(NSDFG) which has the clear physical meaning is discussed. Based on the node movements in the NSDFG, the intrinsic mechanism of legal pipeline scheduling is studied in detail. The study proves that from any initial point in the design space any legal scheduling can be searched through the legal node movements. The self-contained set of legal transformations derived in this paper provides a key for the search-based algorithms to be applied in pipeline scheduling. Results for some examples are presented also.

Abstract:A general space-time CDMA system model in multipath fading channels is built to study how to suppress both multiple access interference (MAI) and multipath fading. Identification conditions are first studied. Then a FIR solution of space-time decorrelating receivers is implemented by an optimal criterion with multiple constraints and system performances are analyzed.

Abstract:Two questions about matrices are discussed.One is answered, the other is answered in case its rank=1,2,3,4,5 resp.. The results obtained in this paper can be extended in many occasions.

Abstract:A counter example is giving to show that the integral formula of fractal interpolating functions in［１］［２］is false. Furthermore, the correct formula is established.

Abstract:In system performances, the phenomenon of gradual failure can't be analyzed by traditional (Probist) fault tree. To solve this problem, the model of Profust fault tree and its partial quantity analysis is given according to the theory of “probability of fuzzy events”. The prominent characteristic of this model is that it employs both the available possibility and probability information of the given system.

Abstract:The interpolating splines of differential operators with constrained functionals are discussed. A general method for constructing the reproducing kernel is presented, this reproducing kernel is determined by the constrained functionals and differential operators. The structual and continuous properties of the splines are derived by new methods, which dependent on the relations between the bases for the null spaces of the differential operators and their adjoint operators.

Abstract:During the course of testing the malfunctions, the time for each testing point to test the malfunction may be different. The paper studies the problem how to choose some testing points to test all the malfunction，which take the least testing time .We turn the problem into an integer programming. An arithmetic to the problem is given. Finally we give an example with the arithmetic.

Abstract:We deal with simple graphs only. Let G be a graph，and g(x) and f (x) be integer-valued functions defined on V(G) such that g(x)≤f(x) for every x∈V(G)．Let H is a subgraph of G and F={F₁,F₂,…,F_t} is a (g,f) factorization of G. If |E(H)∩E(F_i)|=1, 1≤i≤t，then we say that F is orthogonal to H．In the paper［3］,Yan Guiying and Pan Jiaofeng gave the conjecture：Let G is an (mg+k,mf-k)-graph，1≤k

Abstract:For a set of m segment in the plane,we abstract the real light source into the linear light source with limited length.Its visibiity is discussed,and the fact is found that the linear light source is equal to the superposition of the two linear light source endpoints'doing.An algorithm for looking for all visible edgesis given and the algorithm in paper［1］is extended.

Abstract:This paper deals with the Monte Carlo Simulation of the transport of high energy ions in materials, The incident high energy ions interact with the target material in a way is approximate to the two unrelated mechanisms, nuclear scattering and electronic process. The energy loss of incident ions due to nuclear scattering is calculated using binary collision approximation.The impact parameter is sampled and scattering angle can be derived. The electronic energy loss of incident ions for the high energy is calculated by Bethe-Bloch formulation. Lindhard-Scharff formulation is used for low energy and the interpolation formulation is used for the medium energy region. Finally, the computer simulation of high energy irons transport in aluminum and silicon is made, and the results are presented and analyzed.

Abstract:The study of pulse transformer is one of the key problems of pulsed power conditioning system.The technical requirement and the construction parameters of the pulse transformer are presented.Test results of the transformer are also given.The inductance of the primary coil is 3.6μH,and the coupling efficiency is 0.77.When input voltage is 60kV,output voltage can be 500kV.

Abstract:A 21/2 dimension particle-in-cell(PIC) code is used to simulate a coaxial virtual cathode (vircator). By changing the geometrical and electrical parameters of the device, a series of regular knowledge has been achieved .Simulation results show that the output power of microwave is enhanced and the phenomenon of multiple frequencies is also suppressed by adding an electron collector.