Abstract:Taking the towline respectively as "rigidized-flexible suspended cable " model and "linear spring" model, this paper builds the dynamic model of a towed air-launching system, simulates and calculates its full flight course in a longitudinal plane, including take-off, climb, level off and level flight. The simulation results obtained by applying the two towline models are almost the same, and can be used for assessing the feasibility of towed air-launch Reusable Launch Vehicle (RLV). And the algorithm for simulating the system flight is feasible. In addition, the towline's forces that act on the towed aircraft and the towed vehicle are studied in detail. The results verify mutually the feasibility of the two models of the towline. In a word, these two models are applicable for such multibody system.

Abstract:The engine combustion stability is analyzed and the combustion efficiency is calculated under the condition of high altitude and low velocity. The result indicates that when H = 20km, M = 0.7, the combustion in the chamber is smooth and the combustion efficiency is high.

Abstract:To improve the efficiency of UAV in combat mission, a highly effective flight path for the UAV in the execution of the mission should be planned before the mission. This can ensure that the UAV should arrive at the target with a higher survivability and an acceptable path length. In view of this problem, this paper presents an optimal method of path planning based on the Ant Algorithm. The simulation results show that the method has some good characteristics and is effective in path planning.

Abstract:The pressure of a certain airplane surface is calculated. Based on the superpose principle of current field, a two-dimension model with a planar point-fountain, a point-converge and a constant current of current field is established. According to the corresponding relationship between the main parameters of the model and the geometric parameters of the airframe, the model can be translated to three-dimension and expressed accurately. The rule of pressure distributing on the airframe surface can be gained from the characteristics of the current field. Finally, the contrast between the experiment and the calculation shows that the model and the procedure are exact, and the model can be used in a wide range.

Abstract:To study the influence of first vane made of unreflecting material on turbofan engine, a rational test method is proposed and realized and the test data are acquired. By analyzing the data, it is found that the influence is negligible. The test validates that the calculation is reasonable.

Abstract:To meet the demand that the subsoil should be strengthened quickly in the construction of airfield, a new explosion compaction technology applied to subdrade strengthening in airfield is proposed and the function mechanism is analyzed. The construction method and some important parameters are brought out by the site-test and analyzed in theory.

Abstract:This paper is concerned with the problem of nonlinear filtering in homing guidance when the target moves at the rater of an acceleration. First, a filtering model is built. Then the algorithm of filtering is derived. At last, an estimation is done by extending Kalman filtering method. The Monte - Carlo simulation shows that the method mentioned above is available for use.

Abstract:Air-to-surface strike is a valid means of capturing the air superiority and supporting the ground troops. For validly analyzing effectiveness of attacker, on the base of aviation weapon performance index and the combat background of breaking through enemy anti-air firepower, the WSEIAC model of strike for attacker and the method of settling the model parameters at the angle of actual combat are put forward. A basic process of the effectiveness evaluation is given and an analysis of living example is made. The result indicates that various factors affecting the system effectiveness are fully considered and the established model can objectively describe the essence of air-to- surface strike combat for attacker and can give a reference to the battle commanders.

Abstract:On the condition of radar net, the main factors that effect the precision of guidance radar data fusion is discussed in detail, and several main error sources are analyzed. When one radar station can be supported by a few other radar stations in the guidance radar net, by adopting some high precision approaches such as ellipse globe and linear bias, the data fusion process formula and error matrix of this radar station are derived. The Monte Carlo simulation approach is used to analyze the precision of data fusion in guidance radar net, and the result analysis of simulation is also given.

Abstract:A fusion method of multi - sensor data is presented based on gray incidence analysis. The process of this method is to compute the gray incidence matrix of multi - sensor data, to analyze gray superior, to make the multi - data fusion. In the method the influence of each sensor's precision is taken into account and the precision lower data and the data can not be obtained by measurement are deleted. The simulation result indicates that the reliability and tracking precision of fusion system can be improved by using the method. It is suitable for the multi-sensor data fusion.

Abstract:This paper makes a comparison between the results of controlling the double inverted pendulum system with the optimization control of LQY, variable structure control and fuzzy control, discusses the design method of this typical non-linear unsteady controller in theory, and simultaneously points out the advantages and disadvantages of these three controls through digital simulations.

Abstract:The applicability of SD (System Dynamics) for antiaircraft information war research is clarified. The SD model of antiaircraft information war is established and presented. By the simulation of the model, the importance of domination to information in air defense is discussed and the further application of the model is prospected.

Abstract:On the basis of analyzing the frame of the DIS simulation system, the entity dynamic model, self-rule action producing and operator controlling of the attacking CGF system in the simulation system are discussed. Finally time-space consistency in the simulation is shown. It is of significant guidance for the study of DIS - based CGF system.

Abstract:According to the principle of target allocation in air - defense battle and the maximum profit of fire in the target allocation scheme, a target allocation algorithm is presented, and the results are figured out by the Greedy algorithm.

Abstract:According to the basic performance index of the portable missile and the cruise missile, the fighting efficiency of the portable missile resisting the cruise missile is analyzed and calculated. The result of calculation is also presented. At the same time the technical approaches are proposed to improve the fighting efficiency of the portable missile resisting the cruise missile.

Abstract:The assessment of the extent of threat from an air raiding target, as one of the key problems in the decision of air defense command, involves many uncertain factors and some other unknown factors which will make the information available insufficient for the decision - maker to determine all the attributes of the air target. Therefore, by employing Dempster/Shafer Theory of Evidence (DST) to deal with ignorance and incorporating Analytic Hierarchy Process (AHP), the method for threat sequencing based on partial unknown attribute value is presented. In addition, an example is applied to show the method.

Abstract:Properties of Bluetooth frequency hopping sequences, including Hamming correlation property, property of balance, multiple-access property and capacity of FH communication system, are analyzed. Some of the bluetooth FH sequences will overlap seriously if they are synchronized in time, so solutions to this problem are presented. The best one among them is, in one district, that addresses A27-0 of any two Bluetooth devices should be different from each other in three parts: A27-19, A18-14, 12, 10, 8, 6, 4, 2, 0 and A13,11, 9, 7, 5, 3, 1, the more the different bits' number of the Bluetooth addresses is, the better it is. The different bits should be distributed as scattered as possible.

Abstract:By using the general theory of multimode squeezed states, the difference squeezing of generalized nonlinear unequal - power higher - power in the multimode Schrodinger -cat state entangled light field is studied in detail. This light field is formed by linear superposition from three quantum states, i.e. multimode complex conjugation coherent state, multimode complex conjugation imaginary coherent state and multimode vacuum state. The conclusion shows that 1) the difference squeezing of the cat state entangled light field is independent of the vacuum state; 2) when certain conditions are satisfied, the two quadrature phases of this cat state entangled light field present unequal - power higher - power difference squeezing properties respectively, and under some other conditions, the difference squeezing effects of two quadrature phases can be displayed at the same time. The former is in conformity with the uncertainty principle. But the later is not, and is called "two-sides difference squeezing" considering the application of squeezed light in the light communication.

Abstract:The designing and realizing of the VSAT RF power amplification chain are presented. Based on the applying environment and the technique requirement, the number of the stages, the Gain of each stage and the output power of each stage are designed. Again based on the requirement of low cost and small volume, the configuration, active devices and substrate material of each stage of circuit are chosen. According to the requirement of system, some power detecting points and power controlling switch are provided for the amplification control chain. The results of design and development show that the circuits can provide 67 dB Gain, 5W output power, ± 1dBpp pass band ripple from 5925MHz to 6425MHz, the isolation of the channel switching is larger than 40dB.

Abstract:A phase - shifted full - bridge ZVS PWM converter with auxiliary branch is presented. The operation principle and the circuit parameters of the converter are analyzed in detail. The proposed scheme is verified on the prototype converter, the power and the operating frequency of which are respectively 1 KW and 100 KHz. Simulating and experimental results proved that the duty cycle loss can be effectively reduced and the impact on the ZVS range of the lagging leg switches can be minimized through the function of this auxiliary circuit.

Abstract:Based on analysis of LMS algorithm, the ELMS algorithm is researched, which is regarded as an improved algorithm of LMS. The performances of the two algorithms are analyzed and compared, and the advantages of ELMS are pointed out. Then, a variable step size ELMS algorithm is proposed, the theoretical analysis and computer simulation indicate that the new algorithm has quite fast convergence rate, better steady performance and can be applied to adaptive systems effectively.

Abstract:Fracture mechanics is adopted in analyzing the concrete cracks. The fracture criterion of concrete is given and in addition, the limitations of this criterion are analyzed. To overcome the limitations, the paper combines the criterion of fracture mechanics with the criterion of strength theory, presents a model of equivalent fracture distortion and, based on the model, derives the stress-strain relationship of the concrete with cracks.

Abstract:A method for automatic marking surface roughness on AutoCAD desk with VBA is developed. By national standard the block and attribute of surface roughness are created with VBA. The style, scale of symbol and the value selection of surface roughness are realized in dibox. The inserted angle and directional acme of surface roughness are determined in vector. As a result, the surface roughness symbol can be automatically marked.

Abstract:Given the number of vertices and the number of edges in a class of graphs, the size and the structure of the minimum maximum component of graphs are studied, through which some significant results are obtained. The obtained results provide a theoretical foundation for the application of the minimum maximum component.

Abstract:In view of the detects of typical mathematic model for the dimorphic system's reliability, a new method, i.e. a matrix analysis method, is put forward to calculate the reliability of discrete multiform system on the basis of analyzing the basic characteristics of such kinds of systems.