Abstract:Through analyzing the characters of aviation material and current situation of it, studying the development roadmap of foreign CBM, enlightened by the development peculiarity and pattern of it, the necessity and difficulty points of implement CBM on aviation materiel are indicated. By analyzing the intrinsic nature of CBM, the deficiencies of implementing it in practice are pointed out. The frame of Synthetical Condition-Based Maintenance (SCBM) is presented ground on current situation of aviation materiel. Then we study the essential contents、technique process and maintenance decision model of it. Finally by analyzing the implement flow in one real control system, the efficiency and feasibility of practice SCBM in aviation materiel is illuminated.

Abstract:The test capability of AEDC and CIRA icing wind tunnel are analyzed. The present situation of building the icing wind tunnel and that of icing test in China are analyzed. The measurements of the important parameters of liquid water content (LWC) and the water droplets median volume diameter (MVD) are researched. In numerical simulation aspect, four parts of icing numerical calculation are summarized, the virtues and defects of different methods are compared. At last, the development trend of the research for icing on aircraft engine is put forward based on the current research actualities.

Abstract:The aim of this paper is the description of the performance characteristics of a powerplant intended for modern STOVL fighters. Based on a general two-shaft gas turbine performance simulation software, a variable cycle engine performance simulation software was developed with introduction of Lift fan and Roll posts modules. The cycle operating parameters were given, such as low pressure turbine nozzle area, mode selector valve area and propelling nozzle throat area. Selected supersonic cruise as designed point of the engine, determined the combination of the parameters which forming the design point of the engine. The performance characteristics of variable cycle engine with a low pressure shaft driven lift fan were calculated and analyzed on supersonic cruise Design Point, SLS and STOVL in this paper. Comparing the parameter values of SLS and STOVL points, it is actually verified that the innovative variable cycle propulsion system offers high levels of thrust augmentation, by altering the effective engine bypass ratio, offering simultaneously improved fuel consumption.

Abstract:In this paper, based on pass-to-coverage ratio and power spectral density, which are the major factors of the airport pavement, we separately construct the carrying capacity mathematics model of airport pavement and the accidental degree mathematics model of the airport pavement. Then based on fuzzy mathematics, we propose the evaluation method of the airport pavement. Then, this thesis selects three domestic airports as the evaluation samples, makes imitation analyses based on actual data, and achieves identical results with the current operation situation of the plane. Also, the evaluation method is an effective mathematics description of the airport pavement condition and gives clear evaluation result according to the computer simulation. The method above gives suggestions to the airport pavement management.

Abstract:As a new type of active control technology, plasma synthetic jet (PSJ) is designed to object the poor robustness of traditional synthetic jet technology. The software is Fluent6.3 and the grids for numerical simulation are structure. The flow field surrounding the PSJ device was simulated numerically to get the evolution regularity of the flow field. The affection on the velocity of the device exit was compared between different discharge durations. The results show that the PSJ device can generate high speed jet which enlarges the instability of flow. The high velocity 439m/s is achieved. It is also suggested that the longer the discharge duration, the higher the speed of the device exit. And it can be used for high speed flow control.

Abstract:Aim at the problem of bearing-only target tracking of mono-station measurement, a new elevation parameter estimation algorithm is proposed which is based on invariable-information of mono-station flight plane and information supported by bearing-only measurement. According to the deduced dihedral angle relation, horizontal supplementary angle and dihedral angle can be easily solved and forecasting formula of target elevation series is given by utilizing target projection course angle calculated by bearing-only series. Finally, an analysis of impact of azimuth noise on elevation error is done. The use of this method preferably solves the problem of nonlinearity of mono-station measurement and the simulation experiment shows that the estimation of invariable parameter of target movement is good in effect and the elevation prediction series are of good accuracy and precision

Abstract:Anti-missile firepower distribution is one of the key tasks of BM, the firepower distribution model and the efficiency of solving it affect the result of the anti-missile defense warfare directly. The research on anti-missile firepower distribution is done, and the model of anti-missile firepower distribution is built. This paper presents a continuous Hopfield neural network-based algorithm for the optimization of the anti-missile firepower distribution and analyzes the convergence and stability. Finally, three representative examples are solved by the method presented in this paper, and the numerical results are present.

Abstract:In order to improve the anti-TBM effectiveness of the surface to air missile weapon, the problem that the disposition of one piece of the surface to air missile weapon system is studied in the paper. Firstly, some major factors that influence the surface to air missile weapon system intercepting TBM are analyzed. Secondly, the rule of the maximum killed depth (KD) is put forward. Finally, by taking the reentry angle of TBM into account and making use of the ballistic trajectory character of approximately beeline, the two optimal models of anti-TBM defense disposition are established which are about "single to single" and "single to multi" fighting patterns. At last, an example simulation is given, which testifies that the models are effective, feasible available and can meet the demand of anti-TBM.

Abstract:This paper discusses the imaging algorithm of high speed space targets in ground based bistatic Inverse Synthesize Aperture Radar (Bi-ISAR) system. Firstly, the system model and the target echo signal form are given; secondly, the influence of space target moving on two dimension resolution is analyzed. Based on the above, the echo signal is analyzed and disposed, when the targets moves in high speed, it will induce the Residual Video Phase(RVP) and ambulating factor pulse inner ,then the compensation function is constructed to compensate the influence, furthermore, the Keystone transformation is used to eliminate the MTRC and the whole imaging flow is given. Finally, the simulation imaging of satellite target is given to validate that the infection of the RVP and ambulating factor pulse inner can't be ignored. The comparison between the before and after compensation images shows the effectiveness and practicability of the proposed algorithm.

Abstract:The error estimation of guidance radar is a foundation and prerequisite for information sharing among radar stations. Aimed at the error estimation of radar station without reference data, the niche genetic algorithm is adopted to solve the difficulties. Compared to the traditional genetic algorithm, the use of the niche genetic algorithm can overcome the shortcomings of premature convergence and slow convergence rate at ending. The simulation and the project practice show that the algorithm is reasonable and feasible. The guidance radar's error margin estimation plays an important role in the coordination among radar stations.

Abstract:To solve the problem of airborne missile depot test, the concept of test with case is proposed. Test requirement, contents and process, key technologies of testing with case are well studied. Test with case can help to promote the logistic supporting efficiency, extend missile life, and enhance the reliability of missile. Our work and research are of instructive significance for the realization of airborne missile test with case.

Abstract:The simulation of flight checking is of an important value for the real flight checking. According to the technology system and navigation principle of the microwave landing system (MLS), a laser simulation flight checking hardware-in-the-loop simulation system of MLS based on scale model is designed and established. The realization theory and technology of the environment model of the simulation system are studied. The technology of preparation of some typical materials is researched. Finally, a scale model of a real airport is set up, and a model test is made. The test result indicates the validity of the model test system of MLS.

Abstract:The selection of Frequency Hopping (FH) sequences is a crucial factor affecting the quality of FH communication in asynchronously organized networks. According to the requirement of FH communication in asynchronously organized networks, some definitions such as the frequency similarity, the sequence similarity, and the collective similarity are put forward, and then the similarity matrix of available FH sequences is constructed. The hierarchy clustering analysis method is introduced to analyze the clustering structure of FH sequences in characteristic space. Based on the principle that the similarity of suitable FH sequences used in different networks should be the least, the optimized sequences can be selected from different clusters finally.

Abstract:The generation of the reference current waveform is the key technique of the design of the nonlinear electronic load. The harmonic information has to be known when the harmonic superposition method is adopted. By this method, the simulation of nonlinear load with arbitrary parameter can not be realized. In order to solve the limitation of the traditional method, by taking the rectification circuit for example, a method of generating the reference current waveform based on analyzing the equation of state of the circuit and the load parameter is presented. In the hardware realization, an algorithm combining the CORDIC with the interpolation is adopted for the speed and resource factors, thus reducing the consumption of clock period and hardware resource. The simulation done with MATLAB and Quartus II software shows that the use of this method can generate the nonlinear electronic load reference current waveform consistent with the theoretical current waveform by consuming less clock period and hardware resource.

Abstract:Pulsed remote field eddy current (PRFEC) technique integrates the advantages of richness frequency components of pulsed eddy current testing and remote field technique adapt to inspect ferromagnetic pipeline, which is used for detecting axial crack in pipelines. In this paper the principle of PRFEC is analyzed, four sensor models of different structures are designed, the detection effects of pipeline by four sensor models are simulated, the distance of transition field and the detection sensitivity for axial crack and the detection result of pipelines of various wall thicknesses are studied. The result of simulation shows that the model with the core connected through the exciting coil has the better testing ability.

Abstract:Based on the critical damage principle, a new prediction model for fatigue crack initiation life (FCIL) is developed through taking the cyclic damage strain range as the damage parameter. Correlations between the monotonic tensile data and two of the material constants (the stress fatigue-resisting coefficient and the theoretical fatigue threshold) in the proposed FCIL prediction model are founded as well. In contrast to Zheng's model, the fatigue ductility exponent contained in the proposed FCIL prediction model is a material constant which doesn't identically equal to the constant value -0.5. Besides, the fatigue ductility exponent shows the damage resistance ability of the material. The expressions of fatigue life curves with given survivability (PSN curves) for 45 steel notched specimen are developed on the basis of the proposed FCIL predication model. In comparison with the Zheng's model-based PSN curves, the new PSN curves can be used to predict the fatigue life with given survivability of 45 steel better.

Abstract:Three impotant results are given on normalized tight frame super-wavelets in the article. Firstly, A normalized tight frame super-wavelets of length in the space can be extended to a super-wavelets of length in the bigger space .That is a normalized tight super-wavelets frame in the space is extendable to an orthonormal basis in the bigger space . So the relationship between parseval super-wavelets and super-wavelets is found. Secondly, the equivalence of the normalized tight frame super-wavelets are studied by means of the unitary equivalence.The m-tuple remainly forms a normalized tight frame super-wavelets ,when the final component of normalized tight frame super-wavelets is unitarily replaced by a normalized tight frame wavelet. Finally, the conditions of the normalized tight frame super-wavelets are improved. A sufficent condition on a normalized tight frame super-wavelets is given by using space theory. The three results are proofed by using functional analysis. These results function as the important theory basis for the signal processing in the space .