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排序方式: 共有113条查询结果,搜索用时 15 毫秒
1.
动态模糊随机信息处理的数学方法 总被引:1,自引:1,他引:0
本文系统地概述了我们近年来提出的动态模糊随机信息处理的数学方法,内容包括模糊随机变量、模糊随机过程和模糊随机微分方程的基本解法等方面的基本概念、基本定义和某些重要的定理,以及动态系统的模糊随机响应与可靠性分析的方法等。这些方法是为我们研究工程实际问题的需要逐步发展起来的,对于处理某些类型的问题简便实用。 相似文献
2.
研究了直流电场对含LiClO4的聚氧化乙烯(PEO)400与环氧树脂形成的液晶态互穿网络高分子忆禽子导体的电导率的影响。在室温至90℃范围内,电导率随外加电压增加面降低。外加电压越高,对电导率变化的影响越大。 相似文献
3.
We have developed a new numerical ray-tracing approach for LIDAR signal power function computation, in which the light round-trip propagation is analyzed by geometrical optics and a simple experiment is employed to acquire the laser intensity distribution. It is relatively more accurate and flexible than previous methods. We emphatically discuss the relationship between the inclined angle and the dynamic range of detector output signal in biaxial LIDAR system. Results indicate that an appropriate negative angle can compress the signal dynamic range. This technique has been successfully proved by comparison with real measurements. 相似文献
4.
Lei Li Guangyuan Wang Shanshan Wei Xilong Yan Ligong Chen 《Research on Chemical Intermediates》2013,39(2):615-620
A modified procedure for synthesis of the side chain of ceftazidime-activated thioester has been established. This key intermediate of ceftazidime was obtained by a more eco-friendly process than conventional methods, and the yield was much higher (up to 92.4 %). It was found that different organic bases (triethylamine or pyridine) used in this reaction had different effects. The reaction conditions were also optimized to make the route more competitive and suitable for large-scale industrial production. 相似文献
5.
The main difficulty for the numerical calculation of the wave running up a beach is the treatment of its moving water boundary.
In this paper a scheme of turning the free boundary problem into a fixed boundary problem is designed. The calculated run-up
height is consistent with the experiments. Some interesting wave phenomena are also found. 相似文献
6.
Guangyuan Teng Lijing Gao Guomin Xiao Hu Liu Jianhua Lv 《Applied biochemistry and biotechnology》2010,162(6):1725-1736
This paper discusses the synthesis of biodiesel catalyzed by solid base of K2CO3/HT using Jatropha curcas oil as feedstock. Mg–Al hydrotalcite was prepared using co-precipitation methods, in which the molar ratio of Mg to Al was 3:1. After calcined at 600 °C for 3 h, the Mg–Al hydrotalcite and K2CO3 were grinded and mixed according to certain mass ratios, in which some water was added. The mixture was dried at 65 °C, and after that it was calcined at 600 °C for 3 h. Then, this Mg–Al hydrotalcite loaded with potassium carbonate was obtained and used as catalyst in the experiments. Analyses of XRD and SEM characterizations for catalyst showed the metal oxides formed in the process of calcination brought about excellent catalysis effect. In order to achieve the optimal technical reaction condition, five impact factors were also investigated in the experiments, which were mass ratio, molar ratio, reaction temperature, catalyst amount and reaction time. Under the best condition, the biodiesel yield could reach up to 96%. 相似文献
7.
The effect of the impregnation and co-precipitation-kneading methods on the catalytic performance of the Ni/H-ZSM-5 catalyst was evaluated via catalytic reductive deoxygenation of cyclohexanone in a fixed bed. The catalysts were characterized by X-ray diffraction, nitrogen adsorption, and NH3-temperature programmed desorption. A sharply acidic and textural change was observed on the catalysts prepared by the different methods, while the metal active phase structure was almost the same. The results of the cyclohexanone reductive deoxygenation reaction indicated that the catalyst based on the co-precipitation-kneading method afforded a higher yield of cyclohexane, and thus proved that the co-precipitation-kneading method is suitable for the preparation of a bi-functional catalyst. 相似文献
8.
9.
对12年前经离子注入处理后的GCr15轴承钢表面耐磨性能的时间效应进行了探讨。发现离子注入材料的改性效果存在时间效应性。利用AES和X射线衍射分析发现,掺杂原子及材料表面吸附的氧原子的多元迁移和硬质相的生成是造成离子注入材料改性时效的原因。 相似文献
10.
Changjun Min Jinpeng Liu Ting Lei Guangyuan Si Zhenwei Xie Jiao Lin Luping Du Xiaocong Yuan 《Laser \u0026amp; Photonics Reviews》2016,10(6):978-985
Traditional detour‐phase hologram is a powerful optical device for manipulating phase and amplitude of light, but it is usually not sensitive to the polarization of light. By introducing the light‐metasurface interaction mechanism to the traditional detour phase hologram, we design a novel plasmonic nano‐slits assisted polarization selective detour phase meta‐hologram, which has attractive advantages of polarization multiplexing ability, broadband response, and ultra‐compact size. The meta‐hologram relies on the dislocations of plasmonic slits to achieve arbitrary phase distributions, showing strong polarization selectivity to incident light due to the plasmonic response of deep‐subwavelength slits. To verify its polarization sensitive and broadband responses, we experimentally demonstrate two holographic patterns of an optical vortex and an Airy beam at p‐ and s‐polarized light with wavelengths of 532nm, 633nm and 780nm, respectively. Furthermore, we realize an application example of the meta‐hologram as a polarization multiplexed photonic device for multi‐channel optical angular momentum (OAM) generation and detection. Such meta‐holograms could find widespread applications in photonics, such as chip‐level beam shaping and high‐capacity OAM communication.