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JamesM.Dahl 《航空科学技术》2004,(6):43-45
进入新世纪,民用与军用飞机合金的选择设计标准发生了巨大变化。过去的设计标准主张追求更高、更快和更远的目标而不计成本,已不适应时代的发展。新的设计要求包括:一是减少瑕疵、增加使用寿命和降低维修和飞行成本;二是寻求更廉价的零件与部件,以降低产品生命周期成本;三是对更环保的“绿色”部件的需求,如淘汰需要以铬和镉进行表面处理的部件。这些要求使得H-11和300M等一些标准合金失宠,尽管这些合金异常坚硬,但却易产生应力腐蚀断裂。本文介绍了五种新型合金,这五种合金具有延长使用寿命和降低寿命周期成本的优点。它们可用作曾用于起… 相似文献
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F. Dahl G. Klein K. Proetel N. Römisch 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(4):131-134
The German Infrared Laboratory GIRL is a liquid helium-cooled telescope with four focal plane instruments dedicated to astronomical and aeronomical observations.Hardware tests were performed with a thermal model of the cryostat and other components as active phase separator, optical switches, main mirror, baffle etc.In the test phase the thermal behavior of the system was checked out in a step by step procedure. The timeline of the individual experiments and of two representative orbits were simulated by electrical heaters. Temperatures and helium flow rates for the different operation modes were measured.An outlook shows that the project phase in 1982 is dedicated to further development and tests of hardware and complete definition and specification of all GIRL systems. 相似文献
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D. Lemke M. Grewing P. Preussner W. Martin D. Offermann G. Lange S. Drapatz R. Katterloher H. Denner G. Klipping F. Dahl K. Proetel 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(3):11-17
The liquid helium cooled 50 cm-IR-telescope is equipped with a 4-band-camera, a photopolarimeter, a grating spectrometer and a Michelson interferometer. These focal plane instruments allow measurements with high spectral resolution, high sensitivity and diffraction limited spatial resolution in the wavelength region 2.5 … 200 μm. - The “thermal model” phase of the project was successfully completed in 1983. This phase included the development and construction of a full size cryostat, which was thoroughly tested by an experiment simulator. Prototypes of all focal plane instruments have been developed and severral have already been tested under the expected flight conditions. - At present the “flight model” phase to be entered in 1984 is being prepared. The first Spacelab flight of the reusable IR observatory is planned for 1988. It will include measurements in astrophysics, atmospheric science and helium II physics. 相似文献
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用惠普RGS实现CAE仿真远程操作 总被引:2,自引:0,他引:2
惠普公司的创新性软件RGS是一款操作简便、实时性强、图像丢失率极少的远程交互式软件. 相似文献
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