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Multimedia Tools and Applications - Vision based text entry systems aim to help disabled people achieve text communication using eye movement. Most previous methods have employed an existing eye... 相似文献
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随着SAP在公司的广泛运用,从产品研发,工艺制造,物流收发料,到车间生产等工作,无一不是通过SAP系统操作来完成.尤其是工艺制造方面,工作任务多而且繁琐,急需一个能将工艺人员的所有工作任务集于一体的平台,提高工艺人员工作的准确度和效率. 相似文献
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Tensile properties and failure mechanism of 3D woven hollow integrated sandwich composites are investigated experimentally, theoretically and numerically in this paper. Firstly, the tensile properties are obtained by quasi-static tensile tests on the specimens in two principal directions of the sandwich panels, called warp and weft. The experimental results shows that the tensile performances of the warp are better than that of the weft. By observing the broken specimens, it is found that the touch parts between yarns are the main failure regions under tension. Then, a theoretical method is developed to predict the tensile properties. By comparing with the experimental data, the accuracy of the theoretical method is verified. Simultaneously, a finite element model is established to predict the tensile behavior of the composites. The numerical results agree well with the experimental data. Moreover, the simulated progressive damages show that the contact regions in the warp and weft tension are both the initial failure areas. 相似文献
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Sa Liu Yanyan Wang Jie Cai Li Ren Lin Wang Yingjun Wang 《Polymer International》2014,63(11):1930-1935
Supramolecular assemblies with a bottle‐brush structure are obtained by inclusion complexation between β‐cyclodextrin and adamantane. β‐cyclodextrin‐modified chitosan is synthesized via the aldimine condensation reaction between β‐cyclodextrin monoaldehyde and chitosan as the host. The guest is prepared through the esterification reaction between methoxypoly(ethylene glycol) and 1‐adamantanecarboxylic acid chloride. The supramolecular assemblies are formed through the inclusion of adamantane‐modified methoxypoly(ethylene glycol) into the β‐cyclodextrin cavity on the chitosan chain. Fourier transform infrared and 1H NMR spectra were used to prove that the host, guest and assemblies were successfully obtained. UV?visible spectra were employed to confirm the formation of assemblies. Furthermore, the size of the particles in the assembled solution, the change before and after self‐assembly, and the effect of the addition of competitive molecules were studied by dynamic light scattering measurements. The results indicate that supramolecular assemblies have formed successfully which might be used to realize the biomimetic structure of the articular cartilage proteoglycan. © 2014 Society of Chemical Industry 相似文献
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In vitro DNA damage protection and anti‐inflammatory effects of Tartary buckwheats (Fagopyrum tataricum L. Gaertn) fermented by filamentous fungi 下载免费PDF全文
Shiqi Huang Yanli Ma Dan Sun Jian Fan Shengbao Cai 《International Journal of Food Science & Technology》2017,52(9):2006-2017
The present work was designed to investigate the phenolic profiles, DNA damage protection and anti‐inflammatory effects of Tartary buckwheat fermented by Rhizopus oryzae 40469, Rhizopus oryzae 40503 and Rhizopus oligosporus 3152. Six phenolic compounds were characterised and quantified. Regardless of fermentation, rutin was the dominant phenolic substance in Tartary buckwheat. Fermentation significantly enhanced total phenolic and flavonoid contents, as well as DNA scission protection. Rhizopus oryzae 40469‐fermented sample had the highest content of phenolics, while R. oligosporus 3152‐fermented sample had the strongest inhibitory effect on DNA scission. Tartary buckwheat, regardless of fermentation, inhibited nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) mRNA levels in LPS‐induced RAW 264.7 cells. Moreover, the sample fermented with R. oryzae 40503 had the strongest inhibitory activity. Those results indicated that fermented Tartary buckwheat has potential applications as a novel nutraceutical or functional food for preventing DNA damage‐induced disease and inflammation. 相似文献
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H. Cai 《国际通用系统杂志》2014,43(3-4):294-304
In recent years, the leader-following consensus problem for multiple uncertain Euler–Lagrange systems has been studied under some restrictive assumptions on the network topology. In this paper, we further study the same problem under switching network topology. We propose a distributed adaptive control law that can solve the problem under a switching network satisfying jointly connected condition. Under this condition, our results do not require the network to be undirected and allow the network to be disconnected at any time instant. Moreover, by introducing an exosystem to generate various reference signals, our control law can handle a class of reference signals such as sinusoidal signals with arbitrary amplitudes and initial phases or ramp signals with arbitrary slopes. 相似文献