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人工神经网络方法在优化动力配煤中的应用研究 总被引:10,自引:1,他引:10
对神经网络BP算法的一些改进作了大量的数值试验研究,并组合了部分改进方法用于动力配煤问题中状态预测过程的建模,最后把神经网络方法纳入到非线性混合离散变量优化设计方法(MDOD法)中,对杭州配煤场 动力配煤过程作了应用介绍。 相似文献
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一种基于P2P点组技术的流媒体协作计算 总被引:4,自引:0,他引:4
分析了流媒体技术的现状和问题,讨论了在P2P环境下的流媒体多点分布式调度技术和调度性能分析,以及多点调度下的带宽分配算法,最后给出了一个基于P2P点组的流媒体协作调度模型。 相似文献
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Qing Yao Le Zhang Pan Gao Bingheng Sun Cen Shao Yuelong Ma Tianyuan Zhou Ming Li Hao Chen Yun Wang 《Journal of the American Ceramic Society》2020,103(6):3513-3527
Large and nondeforming Nd: YAG ceramic prepared by wet forming is of great importance as gain medium to obtain high-power solid-state lasers. However, it is difficult to achieve high-quality laser ceramics due to insufficiency of the in-depth understanding of transformation mechanism of gels viscoelasticity and effective control means during drying process. In this work, the rheological behaviors, viscoelastic characteristics, and mechanical strengths in classical acrylamide (AM) and novel Isobam (PIBM) gelcastings were systematically compared to explore the suitable route for the large-sized 2% Nd: YAG transparent ceramics with high aspect ratio (>10). AM system exhibited a higher complex viscosity (1.82 × 105 Pa s), a shorter gel time (92.9 seconds), and a higher flexural strength (about 24.46 MPa) than PIBM system, and especially its ability to quickly gel was beneficial to the homogeneity of green body. In addition, the order of drying rates of wet gels in four drying media was observed as follows: 55℃ hot air> ethanol> solid desiccant> PEG-11000 and the moisture diffusion coefficients were calculated and simulated to offer the deep consideration of drying kinetics. The “ethanol + 55℃ hot air” was regarded as an effective composite drying method to eliminate defect and to achieve φ8 mm × 160 mm Nd: YAG ceramic with the in-line transmittance of 83% @1064 nm. Therefore, not only the cognition of gel process, but also the defects control strategy is proposed. More importantly, this work greatly promotes the application of wet forming and laser ceramics in high-power lasers. 相似文献
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Yunfei Chu Yijiao Cen Yanxi Song Zhenxiang Xu Luping Hu Hongqi Li Changling Yang 《Coloration Technology》2020,136(4):381-388
A coumarin‐based fluorescent probe containing both acrylate moiety and an allyl substituent was developed for distinguishing cysteine from homocysteine. The maximum absorption wavelength of the probe showed a bathochromic shift upon addition of cysteine and the colour changed from colourless to yellow. The maximum fluorescence emission at 462 nm of the probe was dramatically enhanced upon addition of cysteine in aqueous solution. In HEPES buffer (pH = 7.4, EtOH/H2O = 9:1, v/v), both of the fluorescence emission bands of the probe at ca. 390 and 462 nm were intensely enhanced upon the addition of cysteine, while other amino acids, namely, homocysteine, asparaginic acid, methionine, glycine, phenylalaninase, valine, tryptophan, serine, glutamic acid and glutathione, did not cause a remarkable change. The probe can be used for selectively colorimetric and ratiometric fluorescent detection of cysteine over homocysteine and other common amino acids in both organic media and aqueous solution. The concentration of cysteine can be estimated by titration of the probe in aqueous solution, and the detection limit of the probe towards cysteine was 2 μmol/L. 相似文献