Abstract:A multi-level and multiobjective optimization (MLMOO) design method for two-dimensional scramjet inlet was established. Total pressure recovery coefficient, static pressure rise and drag coefficient were selected as performance objective functions to form the multiobjective optimization problem (MOP) of the two-dimensional scramjet mixed compression inlet with 4 external compression ramps and 2 internal compression ramps. The concept of multi-level design was introduced into the inlet performance analysis, one dimensional analysis method and computational fluid dynamics (CFD) method were used on the different stages during the optimization design process. To avoid converging to local optimal solutions and using gradient information which was hard to reach for numerical simulation, a multiobjective hybrid genetic algorithm was employed to find Pareto-optimal solutions in one single run for the present MOP. Following the MLMOO design method, the higher performance scramjet inlet would be worked out steadily.

Abstract:Based on an effective nonlinear viscoelastic model, the differential constitutive equation and strain-rate equation of solid composite propellants are induced.Pressure/strain and pressurization rate/strain rate are linear correlation during the ignition transient.And the coefficient is the initial modulus of composite solid propellants.

Abstract:Based on the attitude feedback structure and in improvement of the system stability improving, the system feedback parameters are confirmed for adapting the flight parameters. By the simulation and analysis of six degrees of freedom, it is proved that the system can satisfiy the need of the variable target and the control effectiveness is good.

Abstract:In modern satellite photogrammetry, clusters of low-performancesatellite flying in formation may provide enhanced performance over singlehigh-performance satellite. This is especially true for photogrammetry based on the satellite formation where stereographic imaging may provide higherresolution data. A block is formed by the image sequence acquired with the satellite formation, and the block aerotriangulation by bundlemethod is applied to get coordinateof ground point. Some satellite formation suit for satellitephotogrammetry is introduced and the factors which effect accuracy ofsatellitephotogrammetry is described. The experimental result is given, which would be useful for the development of satellite photogrammetry based the satellite formation.

Abstract:Exampled by a certain launch vehicle, the modeling method and modelingprocess with Simulink to mathematicalsimulation on three-channel for the vehicle attitude control system are described.The problem of the local surge of the calculated data due to the so-called freeze time method during the simulation process is analyzed and the resolvent is given. Algebraic loop problem encounteredinSimulinkmodeling of this large scale system is discussed and the resolvent is given.

Abstract:The figure of the relative kinematical track of the formation flying will change which is in an ellipse because of the disturbing force from which the satellitessuffer. A simple way of control is developed that saves the fuel, that is, in Hill orbital coordinates, through themeasurement of x-axis and z-axis, the control of the small jet engine will eliminate the phase excursion of the center of the ellipse and the non-coplanarity of the orbit of satellites.

Abstract:When using DiffServ AF to transfer TCP traffic, the bandwidth is not allocated in a fair way the previous work does not consider the three factors affecting TCP's throughput all together: subscribed bandwidth, packet size and RTT. The paper proposes DiffServ-Oriented Congestion Control (DSOCC) to resolve the problem on TCP fairness. The validity of the algorithm is verified using ns-2 simulations.

Abstract:Present the application of fuzzy information granulation (FIG) to image interpolation. Granulation structure of image is introduced, and the basic principle of image interpolation based on FIG is investigated. A new interpolation algorithm is proposed based on such granulation structure. It has been testified with better effect than the traditional methods by many experiments.

Abstract:In the Internet-based distributed storage system, the mass heterogeneous data are widely distributed. In order to improve the efficiency of data access, the Tornado-code-based replication algorithm is proposed. Compared with the traditional replication algorithms, the Tornado-code-based replication algorithm can provide better availability，durability and security, and has less storage cost and bandwidth cost.

Abstract:Firstly，generalize the definition of the linear bias of transformation, and then generalize the mathematical description of the linear bias of cipher, and present the relation between the linear bias of cipher and the linear bias of round function F. The upper bound of linear bias of each round within 16 rounds in DES cipher is finally given.

Abstract:An axially extracted virtual cathode oscillator(vircator) with a feedbackannulus is configured through particle-in-cell(PIC) simulation. And the effects of thefeedbackmechanism are studied through PIC method. The simulationresults indicate that the new vircator can increase the output power more than two times compared with the conventionalaxiallyextracted vircator under the same condition. Besides it can narrow the bandwidth and purify the modes.

Abstract:The two-star pattern recognition method is researched on the small field of view provided that the sky-area to be observed is fixed. Firstly,the need is stated briefly.Then the pretreatment of the real-time star pattern is presented in short. Subsequently the pattern recognition algorithm used in the article is discussed in detail.And then the process to build the reference star catalog is explained.The simulation shows the algorithm is effective. The result is analyzed. Finally the conclusion is presented.

Abstract:This paper introduces the concept of tasks, task instances and task context into traditionalrole-basedaccesscontrol model according to the weaknesses of the current role-based access control and the characteristics of distributedworkflowsystem. We propose a task & role-based access control model, whose architecture is not user-role-permission but user-role-task-permission, and its formal definition. This model overcomes the weaknesses of the bad dynamicadaption and the fake constraint of the least privilege. It can enhance the security and practicability of the distributed workflow system.

Abstract:The notion of joint spectrum in polarizational and spatial domains is proposed for the first time, which can depict the EM signal completely. Based on the polarization sensitive array, the joint spectrum is defined and its analytic function is presented by using MUSIC method. The estimation accuracy and resolving power are investigated to measure the performance of joint spectrum. The Cramer-Rao Bound (CRB) is used to evaluate the accuracy of the estimated direction of the arrival and polarization angle. The ambiguity function and ambiguity area are used to evaluate the resolving power in polarizational and spatial domains. The simulations verify the superiority of the joint spectrum and coincide with the theoretical analysis.

Abstract:One of the key issues of the virtual studio based on the electromechanical tracking is camera calibration and initial alignment. This paper analyzes the structure and request of the virtual studio based on the electromechanical tracking, and proposes flexible methods to calibrate and align the camera in the virtual studio based on the electromechanical tracking. Both simulated experiments and the real data are used to verify the methods. The results demonstrate that the proposed methods is easy to manipulat and satisfy the needs of the virtual studio system.

Abstract:The concurrent subspace design is an effective method in multidisciplinary design optimization, but its search strategy has two shortcomings: one with limited ability of finding global optimum solution, and calculation complexity. To remedy the shortcomings of this search strategy, genetic algorithm is adopted and an improved current subspace design method is presented. The design process is introduced. The optimizing calculations for a test problem are finished and the results are satisfactory.

Abstract:Based on the framework of spaceborne parasitic SAR system and considering spacebornebi-staticSAR configuration formed by the existing satellite and eachmicro-satellite, a geometrical model is established, and formulations of spatial resolution in range and in azimuth are deduced. Finally varieties of the spatial resolution in range and in azimuth along with the angle of incidence, height of the relative orbit and the range between the existing satellite andmicro-satellite are simulated and analyzed. The results indicate: (1) the spatial resolution in range and in azimuth are very similar to the existing satellite's； (2) the range between the existing satellite andmicro-satellite is longer, the spatial resolution is bigger； (3) the height of the relative orbit is greater, the differences of spatial resolutions of eachmicro-satellite are bigger.

Abstract:The discrimination problem of the active decoy and radar target is studied based on the full polarization measurement radar system in. Firstly, the polarization characteristic of the active decoy is analyzed under the condition of which antenna polarizations are circular polarization and linear polarization. Then, some polarization scattering properties of the radar target are also discussed. The co-polarization and cross-polarization ratio and its characteristics are presented, which can effectively of the polarization characteristic difference between the active decoy and radar target. A novel polarization discrimination proposal of the active decoy and radar target is given. Finally，the feasibility and validity of the discrimination proposal are verified by computer simulation and actual measured data.

Abstract:A dwell time algorithm for the magnetorheological finishing (MRF) of the small axis-symmetrical aspherical surfaces is described. The dwell time at each dwell grid is calculated as integer multiple of the workpiece rotation period. The removal rate on the surface of workpiece is transferred to a removal matrix. Nonnegative least-squares solution is used to obtain the optimal solution of the dwell time. A piece of axis-symmetrical aspherical surface glass is polished on the MRF experimental facility developed by us. After iterative polishing three times, the residual error of the workpiece decreases from 8μm to 0.5μm.

Abstract:One of the new kind of planetary tranmission composed of the ring involute spherical gear and its driving mechanism is introduced, and the conformation of the new planetary tranmission, and kinamatic are also analyzed. The new planetary tranmission is composed of two spherical gears and one bracket. The output axle can swing toward all directions. Synthesizing one of the spatial driving mechanisms which is used to control the orientation of the bracket. The movability of the driving mechanism is analysed. The kinamatic model between the orientation angle of the output axle and the control motor has been found, based on which the orientation angle can be controlled accurately.

Abstract:This paper studies the fatigue enhancement mechanism of the super-Gaussian amplitude distributioncharacteristic. At first it is demonstrated that the responsestressesamplitudedistribution is super-Gaussian in the repetitiveshockmachine. Then it isproved that the super-Gaussianrandom stressed have higher efficiency to stimulate fatigue failure than Gaussian random stresses of the equivalent lever. Finally the fatigue enhancement mechanism of super-Gaussianamplitude distribution characteristic is illustrated.

Abstract:A MINLP model based on the single fault resolution is proposed. The model takes into account the sensor failure probabilities and fault occurrence probabilities of the equipments, and it is constrained by FDR and FIR to attain optimal sensor selection in test design for mechatronics equipments. The model is applied to a servo platform to highlight the utility of the model.

Abstract:This paper presents a new type of driving and echoes detection circuit for ultrasonic transducers based on the analysis of their working mechanization. The driving circuit consists of a power amplifier, a pulse transformer and a compensation circuit. The echoes detection part is made up of a preamplifier, a band-pass filter and an ALC circuit. The experiment shows that this circuit can improve ultrasonic ranging distance and has good performances than the original ones.

Abstract:We have constructed a second order accuracy finite volume scheme on Euler equations, the new scheme consist of two steps for each time step: the first step we take into account the effects of acceleration caused by pressure gradients, and the second step transport effects are computed. A non-oscillatory linear reconstruction of flow variables is applied, the result of numerical experiment is satisfactory.