Abstract:With the rapid development of biotechnology and informatics, bioinformatics emerges. An introduction and overview of the current state of the field of bioinformatics are proposed and some representative studies are also introduced and analyzed. The characteristics of current and future research are summarized and a few of questions to be resolved urgently are proposed finally.

Abstract:The fundamental principle and construction of ion thruster are introduced. The operating principle and characteristics of the main components and subsystems of ion thruster, including the ion optic system, hollow cathode, ionization chamber, neutralizer etc. are analyzed and discussed. The development trend of ion thruster and its key technology is indicated.

Abstract:Based on the theory of transfer function method of distributed parameter system, a semi-analytic model of structural dynamic characteristics for solar array is established. In this model, the solar panel is divided into some strip elements, and the joint hinge on solar array is simplified as a uniform beam element, and the strip element and the beam element are combined by displacement continuum and force equilibrium at their common nodes. Numerical results of modal characteristics for single and composed panels of certain satellite solar array are presented, and these results are compared with those of finite element method.

Abstract:High precision,high resolution schemes have significant means in raising the level of the complex supersonic flowfield calculation. WENO schemes are new schemes recently developed which are based on the ENO schemes. The algorithm of weighted factors in WENO schemes was studied and analyzed by theoretic and numeric method. Then, the improvement of algorithm was given. Through applying the improved algorithm to two model problems, it shows that the weighted factor of improved schemes is more smooth. The improve schemes preserve high precision, high resolution characteristics and solve the problem of week oscillatory with varied mesh.

Abstract:It is very important to study Large Scale Networks Intrusion Detection and Warning System(LSNIDWS), which can increase the network systems reaction ability to catastrophe, slow down the harm of the network attack, enhance system counterattack ability.The summarization of studying situation in the world is first presented. Then, the structure and its component of LSNIDWS are presented.Finally, the key technology and difficulties related to building LSNIDWS prototype are discussed.

Abstract:To solve the distributed hierarchical network security problems, a distributed simple strictly hierarchical (DSSH) PKI trust model is presented. This model provides effective network security services such as authentication, access control, integrity, confidentiality, non-repudiation and so on. On the basis of the trust model, the concept of the issue-seal certification is presented and established to ensure the security of the seal file in the CA domain. The system implements the digital signature and verification of the electronic documents by the electronic seal. The key, which encrypts and decrypts the electronic documents, is protected by the encryption certification. Finally, the system implements the management of printing seal files abilities through the authority server.

Abstract:Multidimensional modeling is one of the chief techniques in conceptual design of data warehouse. If ER models of traditional databases can be directly transformed into multidimensional models, it would efficiently shorten the life circle of data warehouse design. Based on the traditional databases, an algorithm of the transformation from ER models to multidimensional models is presented. Those ER models under some conditions can be transformed, and the resulting multidimensional models conform to the standard of the generalized multidimensional normal form, ensuring the validity of analytical computations on multidimensional databases. Furthermore, the resulting multidimensional models favor an efficient physical database design.

Abstract:The coupling problems of aeroheating and solid heat penetration are very important to aerospace and engineering applications. The loosely-coupled and the fully-coupled methodology are both applied to simulate a two-dimensional hypersonic fluid-solid thermally coupled flow around a cylinder. The unsteady Navier-Stokes equations and the 2D unsteady heat-conduction equation are derived, solved by the finite volume and the Galerkin finite element methods respectively. The coupling is processed by the boundary conditions of heat flux and temperature at the fluid/solid interface. The flow part is solved by AUSM+ and explicit multi-step Runge-Kutta method. The results are compared with the experimental data and computational results from the reference. The method is shown to give good predictions of the temperature variation and heat flux distribution, and the loosely-coupled method is shown to be more efficient and similar accurate if the characteristic time for fluid is far less than the time for solid.

Abstract:In view of an evaluation system for the air-to-air attack of fighters, the scheme, functions and key technology of this system are described. The development of the evaluation system for air combat in the future is analyzed. Some block diagram for the framework are given in this paper.

Abstract:To meet the need of SAR ATR, based on attributed scattering center model, the extracting method of the scattering center feature from SAR imagery is studied. The method first extracts region including only one scattering center from SAR image by segmentation. Then, the type of the scattering center of the region is chosen. Finally, the initialized values of the parameter are selected and digital optimization is executed by the utilization of the corresponding parameter model of the scattering center, and the scattering center of the target in this region is gotten. By following theses steps repeatedly, all scattering centers of the target can be extracted. Results from simulation show that the algorithm has good estimate performance.

Abstract:For improving reliability of target recognition under the complex background and the strong clutter, a kind of algorithm for IR target fusion recognition based on the theory of fuzzy integration is presented and some experimental simulation with the IR image data from the dual band IR imaging system is implemented. The result shows that the algorithm improves the reliability of the target recognition to some degree.

Abstract:The arithmetic unit allocation is one of the key algorithm in the high-level synthesis. Mainly for digital signal process application, a linear regular datapath model is adopted whose main idea is to minimize the global interconnection. With the initial arithmetic unit allocation constructed by minimal coloring algorithm，stochastic evolution is used to improve the allocation in an iterative way, minimizing the number of the data registers and the data exchanged between the process units. Experiment results with typical design example are also presented.

Abstract:AVL system is a successful application of the integration of GIS and GPS. When GPS data is displayed on a GIS map, logically the vehicle point should be displayed on the roads. But because of the effect of errors, there are always warps between the true vehicle point and the displayed point on the map. It is necessary to correct these warps. An algorithm—Buffer Linear Abstraction Algorithm (BLAA) is put forward. This algorithm improves a former algorithm—Linear Abstraction Algorithm (LAA). Experimental result shows that BLAA has high precision, and at the same time it is more efficienty.

Abstract:A Doppler matched method of high resolution auto-guide sonar system is proposed. The algorithm presented and the aimulation results show that the algorithm can estimate Doppler frequency offset and the target speed in very low SNR condition.

Abstract:The accurate synchronization is a key technique for the receiver to despread correctly. A new algorithm based on software radio is proposed to track the carrier frequency offset fast. Its realization steps and estimation performance are also discussed. This algorithm gains three advantages: (1) The influence of carrier frequency's initial phase is dismissed. (2) It can be used in signals with very low signal-to-noise ratio. (3) It is easy to implement because of its simple structure. The results of the simulation and test show the feasibility of the algorithm.

Abstract:Urged by the request of the reliability engineering, the function simulation models are proposed and discussed. This kind of model can not only describe how the system works, but also discover the functional logical relations of the system and the connections between the performance and function. Moreover, the simulation strategy based on function simulation models is given in detail. Finally, the paper illustrates how the domain-knowledge-based simulation strategy can be applied to the reliability engineering.

Abstract:In ultra-precision machining,the major factors influencing the surface topography of workpieces include many parameters of cutting process such as the tool geometry,feed rate,the speed of spindle and relative vibration between the tool and the workpiece.A surface topography simulation model of ultra-precision machining is established considering these factors.Trimming phenomenon of the tool edge profile is also analyzed at the radial section of the workpiece by the simulation program.It is experimentally shown that good effect is obtained by using the model to simulate the surface topography of ultra-precision face turning.The model can also be used for simulating the traces of tool motion,predicting the three-dimension microscopic surface topography and two-dimension section profile,and optimizing the cutting parameter for diamond turning process.

Abstract:To some flexible spacecraft with a rigid center hub and two identical flexible plates,it can't be simulated accurately depending on the model in［2］because the plate's length causes big elastic displacement. So this paper presents a method with which the system simulating model is built by partitioning the flexible plate into several parts and introducing the floating coordinate respectively. The control rule is designed by taking the plate as a whole. And numerical simulation is done .The simulating results show that this method is very efficient for big displacement.

Abstract:A method for determining the minimum existent range of fault elements for non-null intersection in analog circuit is presented. By assuming the quite realistic K-fault hypothesis, an optimum set of testable elements that represent all the circuit elements is determined. Therefore the work for the fault location can only operate in the elements of this group. So the method constitutes the first step in the development of whatever procedure for the fault location of analog linear circuits.

Abstract:Wavelet-Radon transform is defined that results of wavelet analysis are Radon-transformed. Results of wavelet analysis of linear chirp signals are curves on time scale scheme in general. However, Results of wavelet analysis of linear chirp signals are beelines on time frequency scheme. Radon-transform can detect beeline perfectly and the parameters of linear chirp signals are obtained exactly. The simulation experiment results prove that Wavelet-Radon transform is a good method of linear chirp signals detection.

Abstract:This paper is based on the discussion of the law of the interaction between the optic-field and fluid-field.The physical model is used which is high-energy laser beam to cross through the two dimension super-sonic free shot flow. It is discussed that the disturbance of the fluid-field caused by the radiation heating and the changing of laser beam's intensity after the beam passing through the fluid field and propagating a long distance in the steel atmosphere. The results show that there's a distinctness infection of fluid-field to the optic-field.In studying the interaction of high-speed fluid-field with high-energy laser, the radiation heating will be ignored.

Abstract:TFT-LCD is a very important spatial light modulator in the optical information processing. The positive optical image,the edge weakened optical image and the negative optical image are obtained by changing the direction of the polarizer or analyzer when the spatial light is modulated by TFT-LCD with the digital images inputed. It is explained in accordance with the theory of the linear-twisted liquid crystal device as an spatial optical complex amplitude modulator.

Abstract:PWM is introduced to calculate the phononic band gaps for two dimensional liquid phononic crystals with square lattices. Complete phononic band gaps are found in the carbon tetrachloride/mercury composite system, and all these band gaps reach the widest point for a filling fraction of ～22%. Among the three different shapes of the inclusions' section studied, the circular section is easier to attain large band gaps than the square section and obliquely rotated square one. The widest band gap ΔΩ=0.5497 appears in the circular section system when the filling fraction f=0.229. If the substances of the inclusions and matrix are interchanged (i.e., mercury/carbon tetrachloride system), the gaps obtained are much narrower.

Abstract:The expected return rate μ and volatility σ²of stock are estimated.Some opimal properties of the estimaters are proved.The method for testing singular market is given.The first and second critical value are proposedsented.