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为实现超声磨削氧化铝陶瓷中磨削力变化趋势的预测,提出了一种基于模糊信息粒化和支持向量机相结合的方法。首先进行氧化铝陶瓷超声磨削试验,然后利用模糊信息粒化方法对试验获得的磨削力进行粒化处理,并将人工免疫系统算法和粒子群算法进行并联混编构成人工免疫系统粒子群算法(AISPSO),接着建立非线性回归支持向量机预测模型并对模糊粒子进行预测,并通过AISPSO算法优化支持向量机预测模型,最后获得超声磨削氧化铝陶瓷中磨削力的变化趋势和变化范围。结果表明:该方法可以有效实现超声磨削中磨削力的变化趋势及变化范围预测,且预测未来5组数据变化范围的误差在10%以内,这为通过磨削力变化调整工艺参数以获得更好的加工表面提供了新的思路。 相似文献
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J.M. Wissing J.P. Bornebusch M.-B. Kallenrode 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(8):1274-1278
The detailed study of the precipitation of magnetospheric particles into the atmosphere is complicated by the rather complex spatial configuration of the precipitation region and its variability with geomagnetic activity. In this paper we will introduce polar oval coordinates and apply them to POES observations of 30 keV to 2.5 MeV electrons and comparable protons to illustrate the dependence of particle precipitation on local time and geomagnetic activity. These coordinates also allow an easy separation of the spatial precipitation patterns of solar and magnetospheric particles. The results indicate that (a) the spatial precipitation pattern of energetic magnetospheric electrons basically follows the pattern of the field parallel Birkeland currents up to MeV energies and (b) at least in the mesosphere the influence of magnetospheric electrons is comparable to the one of solar electrons. Implications for modeling of atmospheric chemistry will be sketched. 相似文献
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This brief report summarized the latest advances of the interplanetary physics research in China during the period of 2006-2007,made independently by Chinese space physicists and through international collaboration.The report covers all aspects of the interplanetary physics,including theoretical studies,numerical simulation and data analysis. 相似文献
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Eduard V. Vashenyuk Yury V. Balabin Leonty I. Miroshnichenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(6):926-935
In this study we applied again to the outstanding solar particle event of 23 February 1956, the largest one in the entire history of observations of solar cosmic rays. Due to significant improvement of the analysis/modeling techniques and new understanding of physical processes in the solar atmosphere and interplanetary space, a possibility arises to interpret the old data in the light of modern concept of multiple particle acceleration at/near the Sun. In our new analysis the data of available then neutron monitors and muon telescopes are used. The technique of the analysis includes: (a) calculation of asymptotic cones of ground-based detectors; (b) modeling of cosmic ray detector responses at variable parameters of the flux of solar relativistic protons; (c) determination of primary solar proton parameters outside magnetosphere by comparison of computed responses with observations. Certain evidence was obtained that the flux of relativistic solar protons consisted of two distinct components: prompt and delayed ones. The prompt component with exponential energy spectrum caused a giant impulse-like increase at a number of European cosmic ray stations. The delayed component had a power-law spectrum and was a cause of gradual increase at cosmic ray stations in the North American region. A numerical simulation of the proton acceleration in the vicinity of the magnetic reconnection region brings to the proton spectrum with exponential dependence on energy. This agrees with observational data for the prompt component. It is also shown that the huge increase in ∼5000% on neutron monitors was due to the prompt component only with the exponential proton spectrum. The power-law spectrum of comparable intensity gave considerably smaller effect. 相似文献
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为解决传统编码器的易损坏、可靠性不高、更换价格昂贵的问题,提出采用非接触式、电感感应传感设计位置编码器的方案。用LDC1312数字电感传感器作为感应探头,检测涂有金属物的旋转圆盘,将其感应测量到的数据通过IIC接口送入MSP430F5529处理数据,实现对旋转圆盘位置的检测。该设计与机械编码器相比,具有寿命长、可靠性高,适用于在油渍、潮湿、灰尘等恶劣环境工作的优点。 相似文献
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不连续增强镁基复合材料的制备与应用 总被引:4,自引:0,他引:4
综述了不连续增强镁基复合材料的制备工艺及特点,介绍了其应用情况,展望了其发展前景。 相似文献