Abstract: The effect of ultrasonic pulse square wave current on 2219-T87 high strength aluminum alloy welds microstructure and mechanical properties was researched based on a novel ultrafast convert hybrid pulse variable polarity TIG arc welding technology. The experimental results show that the microstructur...
Abstract: The optimization with cost function of fuel consumption minimum for Lambert two-impulse transfer was studied. Firstly, the universal variables method was modified to avoid singularity, and it was used to solve the Lambert two-impulse transfer problem. Then for the rendezvous problem with only orbit ...
Abstract: Two shock-capturing schemes were considered: characteristic-based MUSCL (monotone upstream-centred schemes for conservation laws) scheme and WENO (weighted essentially non-oscillatory) scheme. Local linearization was employed when performing characteristic transformation, and limiters were applied a...
Abstract: With the requirement of high reliability and indemnificatory of on-board hydraulic power supply system, the general structure of prognostics and health management (PHM) of hydraulic power supply system based on its fault mechanism was presented, the function of every layer in PHM of hydraulic power ...
Abstract: The electro-hydrostatic actuator(EHA) is a kind of power-by-wire actuator that converts the electrical power into local hydraulic power which combines the benefits of conventional hydraulic system and direct drive electrical actuators. Compared to the servovalve controlled actuator, the efficiency a...
Abstract: Based on Timoshenko beam theory, a multi-beam model was presented for buckling analysis of laminated beams with arbitrary multiple delaminations, using differential quadrature (DQ) method. Comparisons showed high consistent between the critical buckling loads of the model with a single delamination ...
Abstract: A new tension control law based on backstepping control method was proposed for planar retrieval control of tethered satellite system(TSS). The control law was designed in two steps. Firstly, the planar swing angle was stabilized into target value via using backstepping control method. Then, the ret...
Abstract: Along with the prolonging of people-s staying time in enclosed environments such as spacecraft, aircraft, submarine and so on, air pollution in the cabin has become a main factor which endangers missionaries- life safety. To improve the ability of these enclosed environments in dealing with sudden c...
Abstract: An on-line waypoints re-planner was presented .It is capable of adjusting trajectory when some targets are detected. A mathematics model of multi-objective optimization under multi-constraint for re-planning was built. Advanced NSGA-II was adopted to find the Pareto non-dominant route set, aiming at...
Abstract: Due to the imbalance use of switches, some switches of switch matrix in ATE (automatic test equipment) fault early while others not. Switches fault destroys the topology of switch matrix and makes path searching more complicatedly. To achieve switch load equalization and path searching with a compli...
Abstract: An experimental investigation using a rotating platform was performed to obtain the flow and heat transfer characteristics of single-phase water and two-phase pipe boiling water under dynamic load in present work. By changing the parameters, such as rotation speed, inlet temperature, flow rate, and ...
Abstract: For spacecraft suffering from multiple celestial constraints in time-varying space enviroment, an on-board large angle attitude maneuver path planning based on particle swarm optimization was studied. The kinematics of the spacecraft was described by Rodrigues parameter. The full attitude was mapped...
Abstract: The flow induced by plasma actuator in two dimensional incompressible flow was simulated based on a phenomenological model, which was realized by adding the body force source term to the Navier-Stokes equations. The numerical results present that there is a wall jet formed downstream of the plasma a...
Abstract: A loop subdivision wavelet transform algorithm for the unclosed mesh surface was presented. Using the plane on which the mesh boundary located as the reflection mirror, the unclosed mesh can be mirrored as a closed one with the symmetrical structure. In this case, the boundary points of the original...
Abstract: A high-altitude balloon design system based on a new framework was developed. The design theory of integration,opening source and multi-object contrasting were imported. Meanwhile, the object-oriented method was used to conform the data. The project could be designed by using the opening function of...
Abstract: The energy efficient multicasting was discussed. Based on the assumption that each node in the network has a fixed level of transmission power during a multicast session, node-join-tree(NJT) algorithm was analyzed. In order to solve the problem that there may be redundant transmitting nodes in multi...
Abstract: The model of assembly tree was put forward to describe the assembly structure of mechanical products and their assembly relations.The assembly tree model can deal with the functional extension and strengthen the description of the product structure tree which was defined by the designer through asse...
Abstract: The mathematical simulation model on the approach process of carrier-based airplane was built up in consideration of complicated environment. The influence of carrier air wake and crosswind on the carrier-based airplane landing safety was researched through computation and simulation. The strongest ...
Abstract: In order to study gas dynamic resonance performance of coaxial injector, high precision and high resolution NND scheme was used to solve Reynolds averaged Navier-Stokes equations. Numerical simulation was used to study process of oscillatory flow in different coaxial injector-resonance tube system. ...
Abstract: 3-dimensional separated and reattaching flow over a swept backwark-facing step of height h at Re=28000 with turbulent upstream conditions was studied for sweep angles up to Λ = 60° using open field operation and manipulation (OpenFOAM). This new open source software was validated by comparison with...
Abstract: To analyze the loading balance problem, the scalable coherent interface for real time(SCI/RT) TRAIN protocol was simulated by using OPNET . The results show that the incensement of the nodes throughput is quite different from each other, along with the ringlet load increasing. In case of the heavy r...
Abstract: A variable structure control scheme was proposed for the networked control systems with the networks existing between sensors and controllers. However, the full state of plant can not be directly measurable, so an observer-based controller was established. If the considered delay is smaller than the...
Abstract: A certain aircraft carrier hydraulic pressure arresting system was studied. As the main arresting forcing producing components, the mathematical models of the hydraulic block system and pulley buffer system were established according to the basic theory of hydraulic transmission system. Using these ...
Abstract: In view of the current trend of space-borne synthetic aperture radar (SAR) developed toward to the high-resolution, multi-mode direction, considering the characteristics of space-borne SAR system in various modes. The integration indicator system of space-borne SAR system was sumd up. Based on the i...
Abstract: To improve reasonableness in development strategic research and project argumentation, a quantificational evaluation method was brought forward. Based on divisiory development stages and technology sorts, key technologies of hypersonic vehicle were collected and classified. The quantificational eval...
Abstract: Aiming at the problems of information sharing and interoperability in ATS(automatic test system), XML(extensible markup language) was used for ATS modeling, including test equipment, ICA(interface connector assembly), test adapter and UUT(unit under test). Test equipment capabilities and UUT test re...
Abstract: The uncertainty in research cycle was considered to be an important influence on aircraft conceptual/preliminary scheme evaluation (ACSE).Through the classification of uncertainties during the aircraft design process and analysis of their corresponding treatment methods, the probability multiple-cri...
Abstract: Target threat assessment method for air combat was a key problem of cooperative multiple target attack. Aiming at the deficiencies of traditional target threat assessment method for air combat in calculating the weights, a new assessment method based on support vector machines for regression was pro...
Founded: 1956 (
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Sponsor: Ministry of Industry and Information Technology of the People's Republic of China
Sponsored by: Beijing University of Aeronautics and Astronautics