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《中国民用航空》2000,(8)
On August 12,, the MA-60, ordered by Sichuan Airlines, was put into formal operation oilthe air route of Chengdu-Nanchong-Chongqing. It meant that the domestic new generation regional aircraft is available for the commercial service.The regional aircraft manufactured by China has had its prosperity. Y-7 started its service inChinese air transport market 15 years ago, and in its hayday, there were over 80 Y-7s in operation,which made great contribution to China's civil aviation development… 相似文献
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《中国民用航空》1999,(4)
Generalaviation,asanimportantpanofChina'scivilaviationindustryisnowfacedbybadeconomicbenefitsandflightsafetysituation,disorderofthemarketcompetition,deteriorationoftheguaranteeingenvironment,backwardnessoftheserviceandthefacilities,theimperfectionoftheregulation,unclearresponsibility,aswellasthelackofadaPtabilityandthemanagement'saimlessness.Gradually,withthedevelopmentofboththenationaleconomyandthesocietyitisbecomingthehotpointtopromotegeneralaviation.l.Themainpartofthegeneralaviationoperator… 相似文献
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《中国民用航空》2000,(11)
China civil aviation is at present in a crucial time of reform and development, faced with major tasks of separating business operations from government administration, transferring the responsibilities of the administration, and the strategic regroup of enterprises. The rapid growth of the national economy lays a good foundation for China civil aviation. The economy globalization, the trade deregularization, and the regulation integration brought both the opportunity and the challenge to Chin… 相似文献
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《中国民用航空》1999,(1)
AlthoughhitbyboththeAsianfinancialcrisisandtheseveresummerfloods,Chineseeconomystillobtained4growthrateof7.8%in1998,andthetaxcollectedaccordinglyachievedanincreaseofRMB100billionyuan,whichlaidagoodfoundationforimprovingtheeconondcoperationenvironmentin1999.Howeverwhenboththerailwayandthepost&telecommunicationindustryspeededuptheirconstruction,thedevelopmentofChinesecivilaviahonindustryappearedweak.Eventhoughin1998thetransportationvolumesofthewholeindustrywerecompletedfairly,thestatCownedairi… 相似文献
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A type of analog integrating moving window detector for use with a scanning pulse radar is examined. A performance analysis is carried out, which takes into account both the radiation pattern of the antenna and the dynamic character of the detection process due to the angular scanning of the antenna. An expression for the false alarm rate of the detector is first derived and evaluated numerically. The detection performance and angular accuracy are next determined in a direct Monte Carlo simulation of the detector on a digital computer for both no fading and pulse-to-pulse Rayleigh fading. Finally the influence on detection performance of the width used for the moving window is investigated. 相似文献
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Golay's complementary pairing has been a method to increase the utility of binary sequences, because of the temporal sidelobe suppression in the autocorrelation vector summation. Complementary sets of Tseng and Liu and of Hollis exhibit the same effect when several autocorrelations are combined. These complementary pairs and sets of sequences can be extended into long complementary chains by a simple transformation. This transformation is extended here to all pulse compression waveforms. By this method, even though analog complementary sequences cannot be formed, a new class of waveforms, called subcomplementary waveforms, can be formed. Following these rules, repetition of waveforms such as linear frequency modulation (LFM) or linear stepped frequency modulation (LSFM) in a prescribed manner is possible without creating autocorrelation grating lobes or repetitive sidelobes. This method is equally applicable to all analog or digital pulse compression waveforms. 相似文献
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Moyer L.R. Maciel L.J. Brown R.D. Little M.O. Wicks M.C. Weiner D.D. 《Aerospace and Electronic Systems Magazine, IEEE》1993,8(10):10-14
A technique that effectively reduces the dynamic range of the input signal in a radar receiver prior to digitization is presented. The dynamic range reduction is accomplished through a process that predicts the next radar return signal from the previous return signals, generates a replica waveform, and subtracts this replica waveform from the radar return signal prior to digitization. This process allows the radar return signal to be digitized without distortion by an analog-to-digital converter (ADC) having a limited dynamic range. The full dynamic range of the radar return signal is then restored by adding the replica waveform to the ADC output. Test and evaluation results using both synthetic and recorded radar data demonstrate in excess of a 30-dB reduction in the dynamic range of the signal at the ADC input when strong clutter is present 相似文献
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模拟电路故障诊断新方法 总被引:4,自引:0,他引:4
在BP型ANN网络用于模拟电路故障诊断的基础上,提出了利用GA辅助设计的BP型ANN实现模拟电路故障诊断的新方法。实例验证表明,新方法的诊断精度、诊断速度以及建立诊断模型的自动化程度都有了较大的提高。 相似文献
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针对测前模拟法难以应用于较大型电路的问题,提出了通过对下层仿真输出信号采用聚类算法进行分类作为上层仿真输入的方法,解决了由于元器件数目增加造成的工作量剧增的问题,最后对获取知识的结构和诊断过程进行描述。实验结果证实该方法可行。 相似文献
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《航空港》2009,(8)
7月14日,在上海国际赛车场,意大利顶级跑车制造商——兰博基尼汽车公司举办了兰博基尼赛道日试乘试驾活动,100余位兰博基尼客户和记者切身体验了驾乘Gallardo LP 560-4 Coupe和Gallardo LP 560-4 Spyder两款超级跑车在F1赛道上风驰电掣的极致感官刺激。在本站兰博基尼赛道日活动现场,兰博基尼汽车公司亚太区经理——克里斯蒂安·马斯特洛(Christian Mastro)说:中国是个拥有辉煌历史的国家,并且具有巨大的市场潜力,这促使我们不断加大对中国市场的投入,为中国消费者带来全球最顶尖的跑车和最尊贵的服务。兰博基尼跑车所具备的超高性能和非凡动力,能够带给人无与伦比的驾控乐趣和纯粹的力量感受。而兰博基尼的每一款车型产品,都在对其‘纯粹、极端、不妥协'的品牌精神进行着完美诠释。兰博基尼汽车公司中国区经理易纳德(Eginardo Bertoli)介绍说。 相似文献
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A measure of analog correlator performance is considered and interpreted reted as an output signl-to-noise ratio. This quantity is shown to depend on the fourth-order expectation of the input signals and the characteristics of the integrating system. Based on the output signal-to-noise ratio, figures of merit are established for correlators utilizing an ideal low-pass filter, an RC filter, and a finite time integrator. These figures of merit indicate to what degree the correlators reject noise components. For jointly Gaussian inputs, the variation of the output signal-to-noise ratio with the input signal-to-noise ratio is shown to be independent of the integrating system. Finally, a graphical comparison indicates the characteristics of the three systems for several different parameters. This comparison shows that the finite time integrator is superior to the other two systems considered. 相似文献
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《航空精密制造技术》2015,(5)
飞机刹车系统在其地面试验时,为使得试验状态与实际飞机刹车时状态尽可能接近,刹车系统需要真实的飞机机轮速度传感器输出的速度信号。本设计在不改变机轮速度传感器工作环境、不破坏原有机载设备结构的前提下,为刹车系统提供真实的轮速信号,还原真实的刹车系统工作状态,达到模拟飞机在各种跑道条件下起飞、滑行、着陆、中止起飞过程中机轮转速状态的功能。 相似文献