Abstract:From Micro Air Vehicle (MAV) flight control system's basic constitution, this paper discusses MAV flight controller's performance criteria, robustness criteria, security criteria and control energy criteria. The linear model approach is presented based on MAV parametric uncertainty such as mass, span, length of fuselage, placement of mass, flight velocity, and aerodynamic compute errors. The MAV flight controller's Δ-P-K architecture is built, and generalized plant transfer function matrix obtained. And further more, we discusses the μ-synthesis approach by which MAV flight controller is designed.

Abstract:A simple and efficient method PDA is put forward, which can suppress deformation vibration of the solar battery array. The attitude rigid acceleration feedback is combined with the classic PD method used usually in the aerospace engineering. The method has been demonstrated to be efficient in suppression of vibration for the attitude maneuver and keeping by virtue of numerical simulation and experiment. Certain applications may be made to the rendezvous and dock engineering or orbital maneuvour .

Abstract:Spacecraft optimal rendezvous is studied using nonlinear programming method. A recently developed direct optimization technique is employed, which uses a piecewise polynomial representation for the state and controls, thus converting the optimal control problem into a nonlinear programming one. When using the method, the whole orbit is separated to thrust arcs and non-thrust arcs, then the collocation method is used to produce the constraints of thrust arcs, and state transition matrix is applied to producing the constraints of non-thrust arcs. At last, the simulation of coplanar rendezvous verifies the effectiveness and robustness of the method.

Abstract:The interaction flow with lateral jet in hypersonic flowfield was simulated numerically by solving three dimensional full N-S equations, using finite volume method, half implied Harten-TVD scheme and a algebraic Baldwin-Lomax model. The computation result was compared with the test data from foreign articles. The simulation captured the structures of shockwaves and eddies near the jet clearly, and showed the disturbed region to the missile. It proves that the jet has deep influence on the missile.

Abstract:A“Satellite-Earth-Target”geometric model is presented, and the exact Doppler centroid is obtained. On the basis of the simplified model, the yaw steering is found. From the analysis of the two models, a conclusion about the yaw steering's compensation effect is drawn.

Abstract:A 2-D forced-vibration driver for ADs identification of long-span bridge section-model has been developed, by which the section-model is forced to perform 1-D or coupled torsional/vertical sinusoidal motion. In each test, lift force and torsional moment are both measured by force balances, the motions of the model are measured by accelerators, then the eight ADs are obtained by a hybrid method of spectrum analysis and non-linear optimization. The results of a flat plate sectional model obtained in wind tunnel tests by this driver are compared with the solutions of Theodorson flat plate and other published datas,the comparison shows that all of the datas share the same trends.

Abstract:SmCo thin films were prepared by DC magnetron sputtering and the relations between the technological parameters and its depositing rate were studied. The analysis of orthogonal experiments of technological parameters indicates that the sputtering power and the distance between the target and substrate have greater influences on the depositing rate, in contrast to that of Ar pressure in range of 0.5～2.0 Pa. X-ray diffraction reveals that the microstructure of as-deposited SmCo film is amorphous, and a little amount of SmCo₅crystal appears after annealed at 500℃ in vacuum. As for the magnetic properties, the coercive force (H_c) of as-deposited film decreases with the increase of the thickness of the film. The reason why the annealing treatment leads to the decreases of H_c and saturated magnetic field, and the improvement of the initial magnetic susceptibility and saturated magnetization obviously is the reduction of the microstructure defection and the composition undulation during the treatment.

Abstract:The 5-acetyl-2-aminobenzophenone with high yield was synthesized by using p-nitroacetophenone, ethylene glycol, phenylacetonitrile, hydrogen, perchloric acid as raw materials. The reaction mechanism is discussed simply, and the structure of compound is identified by elemental analysis, IR and ¹HNMR.

Abstract:Canny algorithm is used in the segmentation of the cell image and it can obtain better effect of segmentation by setting the appropriate parameters.After the histogram of cell image is analyzed,the Ostu algorithm can implement the two threshold's adaptive setting in Canny algorithm. From the test's result, it can be seen that the Otsu algorithm can solve the threshold's setting in Canny algorithm and it can improve the the effect of cell image's segmentation and the adaptive ability of Canny algorithm.

Abstract:A kind of joint frequency-DOA spectrum estimation using virtual tapped-delay-line array is proposed, which generalizes the classical subspace algorithm to two-dimensional space-time domain. The proposed method has three advantages: firstly, increasing the freedom degrees of the corresponding array leading to an enhanced ability to identify much more emitters; secondly, almost free from estimation bias due to the divergence of signal wavelength from what the array size expresses; thirdly, estimating not only the DOAs but also the frequency domain characters of emitters. The obtained characteristic of emitters is more integral.

Abstract:This paper gives an analysis and summary of the features of the natural terrain, and integrating with the nature trait of tiny terrain,presents a midpoint random displacement method with orientation fractal trait.The result of the test shows that the total outline for original data is preferably generated and rough undulation and anisotropy of the original tiny terrain are preferably reproduced by this method.Thus this is a feasible interpolation method that constructs 3-D terrain.

Abstract:In the satellite navigation and positioning system, Doppler shift is one of the key problems that may degrade the performance of the satellite receiver. By calculating the Doppler shift and its uncertainty in the signal covering area, the relation between Doppler shift and the position of the receiver is obtained. Quantitative analysis of Doppler uncertainty range is derived.A method for compressing Doppler uncertainty is presented.

Abstract:Our open digital video management system named iView is presented, which supports full content retrieval based on multimodal metadata extraction and fusion, and supports kinds of wireless access mode. Requirements of iView are discussed first, then the design of framework. We also describe the key ideas and technology involved. Finally, its future research trend is pointed out.

Abstract:Topological relationships are important spatial relationships, and used in numerous practical applications that involve spatial query and spatial analysis. So it is essential to use formal methods to identify and define a complete and mutually exclusive topological relationship set that can be embedded in spatial query languages. Now, the topological relationships that have been defined cannot represent the topological relationships between the two complex spatial features arbitrarily composed of points, lines and/or polygons, thus the researches on topological relationships are not complete. We introduce the formal definition of mixed geometry, and define a topological relationship set: ｛disjoint, touches, within, crosses, overlaps, contains, equal｝.The set, extending the definitions of topological relationships in ‘OpenGIS Simple Features Specification for SQL’， is complete and exclusive, and can be taken as a unified framework to define topological relationships in spatial query languages.

Abstract:A new method for anomaly detection of the program behaviors based on hidden Markov models is presented. The method uses system calls to represent the behavior profiles of programs based on hidden Markov models. The behavior patterns of programs are classified according to their frequency distributions, and the states of the hidden Markov models are associated with the classes of the behavior patterns. Because the collections of observations corresponding to different states are mutually disjoint, the models can be trained with a sequence matching algorithm which requires lower computational complexity and less computation time than the classical Baum-Welch algorithm. A decision rule based on the probabilities of short state sequences is adopted while the particularity of the model states is taken into account. The performance of the method is tested by computer simulation. The results show it maintains higher detection accuracy and efficiency than other alternative approaches.

Abstract:Spectral models are still the mainstream in global operation NWP now. Based on global spectral model, we discuss two-time-level semi-Lagrangian and semi-implicit integration scheme and quasi-cubic spatial interpolation for the terms evaluated at the departure point. A on-demand massage-passing scalable parallel algorithm has been developed. The algorithm is examined in a 4 nodes dual-CPU SMP Linux cluster. The relative speedup of 4 tasks to 8 tasks is 1.65.

Abstract:Based on the low efficiency of the microstrip patch antenna, a novel easily-fabricated microstrip antenna is presented. The simulation and theoretical analysis is made on the antenna. The measurement of novel antenna's gain is about0.3dB higher than that of the conventional one. The new antenna is worth using owing to its easy fabrication and good qualities.

Abstract:Fast algorithms of code acquisition and tracking for DS/SS are presented based on software radio. Code acquisition can be done via calculating the cycle-correlation between received IF signal and local matched filter, using the auto-correlation's sharp characteristic of PN sequence. Two fast algorithms for cycle-correlation are presented. Their correct acquisition probabilities and average acquisition times are analyzed. Finally a simple algorithm of code tracking and its precision are presented. The correctness and validity of these algorithms have been tested by simulation and experiment, and they can be used especially when the SNR is very low and the size and power of the instruments are strictly limited.

Abstract:The image guidance using image sequences analysis improves the shoot accuracy of missiles greatly. In this paper, we present a new method of automatic object recognition and tracking based on deformable template and genetic annealing algorithm. After the constructing object template and defining energy function according to their features, we use genetic annealing algorithm to search for the optimal solution. Experiment results show the method can be applied to detect and track the object efficiently and accurately.

Abstract:A novel method is proposed by which a M×N dimensional image can be expressed with Mand N dimensional vectors. Therefore, the image can be processed in the lower dimension space and it is easy to calculate. In certain sense this expression is optimum. We prove that it is identical to the result in the literature when the hits go to infinite. At last the applications verify the theoretical result.

Abstract:Boolean permutations are in very important applications in cryptosystems. In the design of block cipher，those of high degree are needed. In this paper，a method of constructing boolean permutations of high degree by combining some boolean permutations of low degree is provided，and an example is given. The results are useful to the construction of boolean permutations.

Abstract:Assuming that there is no arbitrage and there are two securities traded, riskless and risky in the market, by self-financing strategy we obtain the BSDE option price satisfies ,and then we will get the probability expression formula of the European options' price by BSDE. We will give the proof of the complete hedging of the European option.

Abstract:Upper approximation and lower approximation are the most elementary concepts in rough set theory, while the primary idea in rough set theory is to deduct the decision and rule of classification through reducing the attributes and keeping the ability of classification unchanged. This paper discusses the relationship of reduct and relative reduct and the upper approximation and lower approximation. On the basis of the relationship we propose a novel relative reduct-holding approximation reduct.

Abstract:A class of nonlinear sequence generators of long period and high linear complexity are constructed。It is shown that linear complexity and period can be determind。And they are safe if some conditions are given. So they can be used as the key sequence generators。