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401.
根据对飞机噪声控制技术历史发展演化过程的总结分析,研究了民用航空发动机气动与声学一体化设计的目标、方法、流程、理论模型和发展趋势等。基于对航空发动机气动设计过程的分析,给出了航空发动机气动与声学一体化设计的流程和方法。分别从“发动机总体热力循环设计”“发动机部件通流设计”“发动机部件三维详细设计”等三个流程,介绍了航空发动机声学设计理论和技术国内外的发展情况,详细论述了发动机气动声学设计的理论、模型和方法,分析了目前航空发动机声学设计理论的主要问题及未来的研究重点,并以具体发动机设计实例分析了不同设计阶段航空发动机的气动与声学一体化设计方法思想。 相似文献
402.
郝璇周家检张卫民 《民用飞机设计与研究》2014,(3):21-30
空中应急离机系统是飞行试验过程中保证试飞机组人员安全的重要措施。对国外一些试飞飞机的空中应急离机系统进行介绍,并对空中应急离机系统的总体设计原则、组成、功能、设计理念及多种子系统设计方案进行研究及分析。 相似文献
403.
曹涛吴善永邱俊杰 《民用飞机设计与研究》2013,(4):71-74
首先介绍民用飞机蓄电池系统的组成及民用飞机蓄电池的类型;其次,介绍了适航条款对民用飞机蓄电池系统设计的要求,并且将适航条款对民用飞机蓄电池系统设计要求进行分类研究;最后,针对适航条款对民用飞机蓄电池系统设计的要求进行详细说明,表明其对适航条款的符合性。 相似文献
404.
405.
孙运梁 《中国民航飞行学院学报》2011,22(2):12-17
随着航空运输业的快速发展,航空安全问题日益引起人们的重视.劫持航空器、暴力危及飞行安全等犯罪严重危害航空安全,国际社会相继通过了一些国际公约予以规制,我国刑法也作出了相应的规定,力争严厉打击危害航空安全的犯罪,确保航空业的安全、高效. 相似文献
406.
Thomas S. Richardson Cormac McFarlane Askin Isikveren Ken Badcock Andrea Da Ronch 《Progress in Aerospace Sciences》2011,47(8):647-659
One of the main drivers behind the SimSAC project and the CEASIOM software is to bring stability analysis and control system design earlier into the aircraft conceptual design process. Within this paper two very different aircraft are considered, a conventional T-tail based on the existing EA500 Very Light Jet and the second, a novel Z-wing configuration known as the GAV or general aviation vehicle. The first aircraft serves as a baseline comparison for the second, and the cruise case is considered as a benchmark for identifying potential drag reductions and aircraft stability characteristics. CEASIOM, the Computerised Environment for Aircraft Synthesis and Integrated Optimisation Methods, is used to generate aerodynamic data sets for both aircraft, create trim conditions and the associated linear models for classical stability analysis. The open-loop Z-wing configuration is shown to display both highly unstable and coupled modes before a multivariable Stability Augmentation System (SAS) is applied both to decouple and stabilise the aircraft. Within this paper, these two aircraft provide a test case with which to demonstrate the capabilities of the CEASIOM environment and the tools which have been developed during the SimSAC project. This new software suite is shown to allow conceptual development of unconventional novel configurations from mass properties through adaptive-fidelity aerodynamics to linear analysis and control system design. 相似文献
407.
G.E. Dorrington 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Various aerial platforms intended for long endurance survey of the Titan surface are presented. A few novel concepts are introduced, including a heated methane balloon and a balloon with a tethered wind turbine. All the concept options are predicted to have lower scientific payload fractions than the Huygens probe. It is concluded that the selection of the best aerial platform option depends on more accurate mass estimates and a clear decision on whether, or not, in situ surface composition measurements are required in conjunction with aerial remote sensing. 相似文献
408.
409.
The CEASIOM software developed in the EU-funded collaborative research project SimSAC generates stability and control data for preliminary aircraft design using different methods of varying fidelity. In order to obtain the aerodynamic derivatives by CFD, the aircraft geometry must be defined, computational meshes generated, and numerical parameters set for the flow solvers. An approach to automation of the process is discussed, involving geometry generation and mesh generation for inviscid as well as RANS flow models. 相似文献
410.
Inner wrinkling control in hydrodynamic deep drawing of an irregular surface part using drawbeads 总被引:2,自引:0,他引:2
Inner wrinkling phenomenon is more likely to develop during hydrodynamic deep drawing (HDD) of complicated component-forms due to the higher demand for controlling deformation sequences. Aiming at the problems in control of inner wrinkling for an irregular surface part featured with both concavity and convex, this research proposes an optimal design method of drawbead parameters to change the material flow. According to theoretical analysis of the mechanism of inner wrinkling, optimizing cavity pressure only is unreasonable to form a wrinkle-free deep-drawn part, so semi-circular drawbeads are employed. The effects of layout and height of drawbeads on forming results are discussed, and a process window is established based on evaluation indicators including the anti-wrinkle coefficient and the minimum wall thickness. Experiments are carried out to validate the process window, and the wall thickness and the wrinkle height are measured and compared with numerical findings. The results show that the anti-wrinkle ability of drawbeads weakens with increasing oblique angle and distance from the die center, while the wall thickness increases with increasing oblique angle and distance, and the inner wrinkling can be completely suppressed by drawbeads arranged in zones I and II with optimum penetration. 相似文献