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32.
33.
Toughening by Metallic Lamina in Nickel/Alumina Composites 总被引:2,自引:0,他引:2
Tape casting and hot-pressing were used to produce metal/ alumina laminate composites. The mechanical behavior of these laminates was characterized. The strength and toughness of the laminates were greatly improved in comparison to that of monolithic alumina. Indentation strength values of the laminates remained approximately constant for indent loads between 10 and 100 N. Thus, this type of laminate appears to be a good candidate for damage-tolerant composite material design. 相似文献
34.
Partially observable Markov decision process (POMDP) is an ideal framework for sequential decision-making under uncertainty in stochastic domains. However, it is notoriously computationally intractable to solving POMDP in real-time system. In order to address this problem, this paper proposes a point-based online value iteration (PBOVI) algorithm which involves performing value backup at specific reachable belief points, rather than over the entire belief simplex, to speed up computation processes, exploits branch-and-bound pruning approach to prune the AND/OR tree of belief states online, and proposes a novel idea to reuse the belief states that have been searched to avoid repeated computation. The experiment and simulation results show that the proposed algorithm can simultaneously satisfy the requirement of low errors and high timeliness in real-time system. 相似文献
35.
Flakes of natural carbyne were found in Liao-Ning diamond mine, China, and examined by HRTEM, XRD and EDX. Lattice fringes and clear SAD patterns were obtained. The interlayer spacings obtained with SAD were in good agreement with those determined on the powders found in Ries crater meteorite by X-ray diffraction. However, they are different in color and shape, the one found in China being black and flaky, but the one in Ries crater meteorite being silver-white and particulate. It was assumed that carbyne might be stabilized by the intercalation of either Si or Fe in nature. 相似文献
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Hao Liang Zhiqiang Zheng Zengchang Li Jie Xu Biao Chen Hui Zhao Qijin Zhang Hai Ming 《应用聚合物科学杂志》2004,93(2):681-685
A step‐index polymer optical fiber (SI POF) containing Rhodamine B in poly(methyl methacrylate) (PMMA) has been fabricated by a preform technique. Fluorescence of different fiber lengths were observed and discussed. A high gain (23 dB) for a SI POF with 60‐cm length, 400‐μm diameter was obtained. The Rhodamine B content of the doped SI POF is 5 ppm‐wt. The signal wavelength providing the highest gain for a 60 cm SI POF is around 630 nm, and the optimum fiber length is about 60 cm at 10 kW launched pump power. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 681–685, 2004 相似文献
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以最低制造成本为优化目标,建立了新型高压密封装置优化设计的数学模型,并给出设计实例。结果表明,采用优化设计可降低制造成本14.7%。 相似文献
40.
ECN树脂中的可水解氯含量是决定树脂质量的—个重要指标。本文研究了反应温度、ECH/OCN配比、反应时间和碱用量等因素的影响,取得了规律性的认识,并获得最佳配方,制备出高纯度的ECN树脂系列产品。 相似文献