Abstract:A general aeroservoelastic model construction method based on CFD / CSD couple simulation is investigated. The aeroservoelastic system is divided into three parts including aerodynamic, structure and control subsystems whose state equations are built separately and then are integrated into an integral aeroservoelastic system model. The system identification method of the state equation of the unsteady aerodynamics is investigated, especially the identification of the impulse response. A simple moving mesh generation method and an improved CVT method exchanging data between aerodynamic grid and structure grid are applied in the CFD / CSD program. The comparison between the results of the state equation and the direct simulation indicates that the model obtained by this method is good in accuracy, easy in usability and high in efficiency.

Abstract:The impact damage forecast for the airplane structure has great significance for ABDR. This paper analyzes the impact damage forecast for the airplane structure from the following four aspects: ballistic limit, residual velocity, residual mass, forecast of damage size in structure penetrated or not penetrated, simultaneously discusses the development tendency of damage forecast and finally points out the main direction and means in the future damage forecast research.

Abstract:Hydroplaning velocity formulas are established respectively when the water film on road is shallow and the water film on road is deep by applying momentum theory. The result of analysis shows that the hydroplaning critical velocity lies on inflation pressure when the water film on road is shallow, and the inflation pressure is of insignificance to the hydroplaning critical velocity when the water film is deep. Moreover, how the thickness of water film impacts on the hydroplaning critical velocity is analyzed.

Abstract:This paper analyzes the present situation of the new type of sealing materials used in airport concrete pavement, by using the correlative standards both inland and abroad for reference, combined with the environmental characteristics of airport pavement engineering and based on the analysis and experiments, finally brings forward the technical requirements for the new type of sealing materials. After the application of the eight technical requirements to six airports, the results show that these requirements - flow, elastic recovery, tensile modulus, adhesion/cohesion properties at maintained extension after immersion in water / oil, adhesion / cohesion properties at variable temperatures, change in mass and burning resistance - can availably master the material quality and construction quality, ensure the requirements for pavement design and use, prolong the pavement service life.

Abstract:This paper analyzes the core of the electric magnetic bomb - explosive magnetic flux compression generator, builds up its equivalent circuit model, and then focuses on the changes of the number of the equivalent stator loop and the armature radius in the process of operation. Finally it gives an explicit time formula for dynamic inductance ((10) - (16) formula).

Abstract:This article studies the problem of designing a seawave filter and a high integrative system for the helicopter skimming-over-the sea flight. In order to research this question, a sea spectrum in the kinetic coordinate system is derived. Based on Bode-Shanon method, the Wiener filter and the high integrative system are designed. A simulation by a kind of helicopter is made to test the validity of the designed method.

Abstract:A project to realize the encoding and decoding of pulse number, pulse width and pulse spacing in the pulse distance measuring system is put forward by use of software programming. By taking the encoding and decoding of three pulses for example, the concrete realizing process is expounded, and the characteristics of the encoding and decoding by software realization are analyzed.

Abstract:This paper presents a method for MADM of partial weight information. The method consists of three steps --- first optimizing regionally, then forming assigned weigh and ranking all decisions. The method, according to the minimum deviation, constructs the statistics - variable of weight and contains the utilization of both samples information and previous information so as to make the evaluations objective and believable. In addition, IE is employed and optimal mathematics model is set up on the basis of the method. At last, an illustrative example is given to demonstrate the effectiveness of the new method.

Abstract:An improved method of Performance Evaluation of Weapon Systems (PEWS) is presented based on fuzzy arithmetic operations with revising the defects of the original method. PEWS is regarded as a fuzzy MCDM problem. Five fuzzy ratio scales are defined to represent the elements of fuzzy judgment matrix and weight vector according to the data in the "Goal - Criteria - System" structure, and then PEWS is transferred into fuzzy ranking scores. The comparison of the three results obtained respectively by this new method, the original method and the relative grade method shows that the new method is credible and effective.

Abstract:When a certain maneuvering target is inputted, the bias information will change, based on this fact, an adaptive algorithm is designed. According to the residuals of target tracking, the maneuvering frequency of the target is adaptively adjusted, so that the maneuvering frequency is close to the true state of the target. Simulation results show that the tracking error of this model is less, and the algorithm is characterized by simple calculation, high tracking precision and easy realization.

Abstract:According to the characteristics and requirements of the BDAR theory, by taking the ARM of the preformed fragment warhead as a supposed threat, a model is established by employing the analytic method, which can approximately calculate the damage probability of the fragments to the parts of the guided station under the ARM attack. The calculating results tally with the simulation results.

Abstract:The research on the remote fault-diagnosis system in existence is often centered on the diagnosis model and method. Here, following the viewpoint of information theory and system theory and taking the fault information as a beginning, it is pointed out that the remote fault-diagnosis system is a complete process of information processing. Through researching on and analyzing several ways of information acquiring, a general model of information acquiring is presented. Moreover it is pointed out that reasonable information optimizing, resource configuring and mission transporting are important and necessary on condition that the network band-width is limited and the fault information is of huge amount. The present research shows that the studying of fault information is the basis or core of the system in remote fault diagnosis, and it is helpful to the effective and reasonable operation of the system to consider problems from the viewpoint and method of information processing.

Abstract:A novel sampling algorithm is presented for DSP controlled power factor correction (PFC) converters, which can successfully avoid the influences of the oscillation brought by the operational high - frequency switching in PFC circuit. The proposed sampling algorithm can greatly improve the switching noise immunity, especially when the switching frequency is above 30 kHz. Finally a PFC converter with 2kW based on the proposed sampling algorithm is implemented, and the experimental results prove the practicality of the proposed novel sampling algorithm in the analysis, design and debugging of all digital sampling circuits with switching.

Abstract:In this paper, the design technique of low phase noise frequency synthesizer with a time delay frequency discriminator feedback network is discussed in detail, the transfer function of the delay- line discriminator and the phase noise of the loop are analyzed in depth. By using the delay line discrimination technique, the improvement of the phase noise higher than 15 dB in the single loop frequency synthesizer is obtained without substantially altering the VCO turning characteristics.

Abstract:The wavelet transforms are integrated with transform domain LMS algorithm and variable step - size LMS algorithm, from which a new adaptive filtering algorithm is presented based on discrete wavelet transforms ( NDWT - LMS). The algorithm can reduce the cross - correlation of input signals effectively and can overcome the conflict between high convergence rate and low steady - state maladjustment in LMS algorithm which is caused by the fixed step - size factors. The computer simulation results indicate that the higher convergence rate and lower maladjustment noise are obtained by using this algorithm in comparison with LMS algorithm, and the new algorithm is effectively applicable to the adaptive systems.

Abstract:In this paper an algorithm of reducing out-of-band emissions of OFDM based on GI is proposed. OFDM has better bandwidth efficiency and increased robustness to multi-path fading in wireless environment, but the out-of-band emissions of it are high. The algorithm based on guard interval can reduce the out-of-band emissions effectively by using the raised cosine windows. Of course the BER of systems change in a small range, which has been proved by the result of computer simulation.

Abstract:This paper makes great efforts in the software optimization of EVRC vocoder. Based on the understanding of TMS320C64xx CPU structure, a deep optimization of software on the loop operations which appear frequently in voice signal processing is done. This greatly improves the utilization ratio of CPU and the parallel processing degree of CPU function cell. And the vocoder works well in practical application.

Abstract:The marching-on-in-time method is employed in analyzing the ultra-wideband electromagnetic scattering problems of aircraft's basic parts (sphere, cylinder, sheet metal). A magnetic field integral equation is derived, and the result obtained is better in coincidence as compared with the measured or other computed result. The method introduced in this paper is effective, without setting the absorbing boundary conditions, and simple in computation. Its results can be used for imaging reconstruct of radar targets compared with FDTD method, and this method can also be used for solving EM scattering problems of ultra-wideband in comparison with the method used in frequency domain.

Abstract:In this paper, a new frame synchronization and phase offset estimation method is presented, the implementation scheme is also applied. The scheme is implemented by using the transmission of the low power determined frame synchronization signal in the orthogonal channel as an aided information under the precondition that channel utilization efficiency is ensured. The scheme can greatly reduce the complexity of carrier phase offset estimation. The simulation result indicates that the method has good performance.

Abstract:From the point of view of the distribution of code weight, the factors affecting the quality of Turbo codes are analyzed, the concepts of optimal periods interleaving implement for Turbo codes are introduced, and a new design of interleaving implement for Turbo codes is provided. The experiment proves that the interleaving implement designed by using the proposed method has better functions and can be easily realized.

Abstract:Based on Log-MAP algorithm of easy engineering implementation, the two different methods of using extrinsic information, the Berrou and Robertson schemes, are studied deeply in the paper. The study points out that the two methods are consistent, and the only difference lies in the treatment to the scale of weight applied to the extrinsic information in iterative decoding. Under the same constraint condition, by Monte Carlo means the performances of Turbo codes with extrinsic information in different fashions are simulated, and the result shows that Robertson method is better than Berrou method from the overview.

Abstract:A method, which turns the direct estimation of wide difference in frequency into the estimation of period of a known sequence for the digitized demodulation of multi-channel signals, is presented. The wide frequency difference problems difficult to solve by available algorithm for actual demodulation can be simply estimated and rectified by the method. So, the difficult problem for the presently digitized demodulation is better solved. The method is simple in algorithm and needs less computation. And the method is especially applicable to the digitized demodulation of multi-channel signals. The simulation results suggest that the algorithm is practicable.

Abstract:The backtracking mechanism is an important facility for logic programming. The backtracking itself is a good approach to obtaining all the possible solutions to a goal. On the basis of observing and studying the operating elements of backtracking mechanism in Visual Prolog with a group of instances, the four fundamental principles, i.e. those of bottom - up, right - left sequencing, rule matching and fact matching, are expatiated in detail. A backtracking approach implemented by means of repetition is explored. All kinds of possible cases in the course of backtracking are deeply analyzed and investigated, thus the essential characteristics and the applied fundamentals of the backtracking mechanism are revealed. Finally, the conclusion indicates that the backtracking mechanism has side - effects, and it is necessary to control carefully the searching courses by using a cut mechanism, a fail predicate and otherwise.

Abstract:Because of the open structure of TCP / IP, the network is vulnerable to attack. In order to availably detect the intrusion, an intrusion detection system based on components is presented, and the implementation of it in Linux environment is made in combination with the development of NMS software. The system consists of manager console, analyzer, storage system, response system, network engine and host agent. By operating cooperatively and using the improved Boyer-Moore algorithm, the network intruding acts can be detected effectively and the information network security is defended.

Abstract:he paper concerns the calculation of one kind of determinants Dn(m,k,l) made up of Fibonacci numbers. It demonstrates that identity Dn](m,k,l) = 0 when m ≤ n － 2, and a formula is presented for calculating Dn(m,k,l) when]m = n － 1.