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排序方式: 共有437条查询结果,搜索用时 15 毫秒
31.
以可靠度理论为基础 ,建立了厂房系统与子系统的层次概率分析 (AHP)模型 ,重点探讨了承重结构系统的传力树分析方法 ,在同一棵传力树内建立了直接构件和间接构件的概念 .分析了厂房系统的子系统之间、子系统的传力树之间、传力树内的直接构件和间接构件之间的逻辑关系 ,从而得到了大型工业厂房系统可靠度分析方法的实用计算方法 . 相似文献
32.
为了验证立式配平转台原理的正确性,建立了配平转台的力学模型,并通过动力学仿真求出了当旋转体存在动不平衡量时,水平方向和垂直方向两测力仪的输出值,在此基础上对配平修正过程进行了数值仿真.仿真结果表明,配平修正过程是收敛的,说明配平转台在原理上是正确的.仿真结果可为配平转台的设计提供初步依据. 相似文献
33.
Tun Patricia A.; Benichov Jonathan; Wingfield Arthur 《Canadian Metallurgical Quarterly》2010,25(3):730
Older adults with good hearing and with mild-to-moderate hearing loss were tested for comprehension of spoken sentences that required perceptual effort (hearing speech at lower sound levels), and two degrees of cognitive load (sentences with simpler or more complex syntax). Although comprehension accuracy was equivalent for both participant groups and for young adults with good hearing, hearing loss was associated with longer response latencies to the correct comprehension judgments, especially for complex sentences heard at relatively low amplitudes. These findings demonstrate the need to take into account both sensory and cognitive demands of speech materials in older adults' language comprehension. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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2008年初,湖南电网遭受了50年一遇的冰冻灾害,电力通信网也受到了前所未有的严重破坏.面对历史罕见的冰灾,湖南电力通信战线上的广大职工,众志成城、顽强拼搏,取得了抗冰保网的全面胜利.从抗灾措施和体会两方面,全面回顾了湖南省调通信部门在"抗冰保网"中所做的工作,并简要描述了灾后湖南电力通信系统容灾及抗灾技术的研究. 相似文献
36.
Sheu J.K. Lee M.L. Tun C.J. Kao C.J. Yeh L.S. Chang S.J. Chi G.C. 《IEEE journal of selected topics in quantum electronics》2002,8(4):767-772
Si ion implantation into p-type GaN followed by rapid thermal annealing (RTA) in N/sub 2/ has been performed. X-ray diffraction analyses indicate that ion-implanted damage remains even with 1050/spl deg/C, 60 s RTA. By varying implantation and postimplantation annealing conditions, we could convert carrier concentration from p-type 3 /spl times/ 10/sup 17/ cm/sup -3/ into n-type 2 /spl times/ 10/sup 17/ cm/sup -3/ /spl sim/2 /spl times/ 10/sup 19/ cm/sup -3/. It was found that typical activation energies of Si implants in p-GaN are lower than 10 meV. Such activation energies are smaller than those observed from epitaxially grown Si-doped GaN films. A deep donor level with activation energy of 60 meV was also found from some samples. Photoluminescence studies show that the peak appears at 372 nm might be related to implantation-induced defects. It was also found that a green emission band could be observed from Si-implanted GaN. It was shown that such a green emission is related to the yellow band observed from epitaxially grown Si-doped GaN. The transport properties of these Si-implanted samples were also studied. 相似文献
37.
M. Tun Norbrillinda H. Mahanom N. Nur Elyana S. Nur Intan Farina 《Drying Technology》2016,34(14):1735-1744
ABSTRACTSargassum muticum is categorized as a brown seaweed species which has been used as a dye fabric colorant in certain regions of Asia. The brown extracts of S. muticum also have antioxidant properties, which could enhance the color and nutrients in food products. However, the color extract is unstable, and also limits the application. This study was performed to encapsulate the color extract with maltodextrin and stabilize the color extract by spray drying technique using combinations of various levels of inlet temperature and feed flow rate. Initially, S. muticum powder was analyzed for moisture content, water activity, solubility, and color properties for optimization purposes. This study showed that the optimum inlet temperature and feed flow rate of the spray drying process to produce good-quality, stable, and acceptable powder properties were at 140°C and 3?rpm, respectively, with 4% of maltodextrin. Then, the powder was analyzed for density, compressibility index, hygroscopicity, particle size, and antioxidant properties. This study represents an interesting food additive to be incorporated in functional food due to the attractive brown colorant and the presence of antioxidants. 相似文献
38.
In this study, the effects of changing first wall materials and their thicknesses on a reactor were investigated to determine the displacement per atom(DPA) and gas production(helium and hydrogen) in the first wall, as well as the tritium breeding ratio(TBR) in the coolant and tritium breeding zones. Therefore, the modeling of the magnetic fusion reactor was determined based on the blanket parameters of the International Thermonuclear Experimental Reactor(ITER). Stainless steel(SS 316 LNIG), Oxi... 相似文献
39.
Sheng Ye Quanle Cao Panxianzhi Ni Shuting Xiong Meng Zhong Tun Yuan Jing Shan Jie Liang Yujiang Fan Xingdong Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(40):2302152
Cell migration is an essential bioactive ceramics property and critical for bone induction, clinical application, and mechanism research. Standardized cell migration detection methods have many limitations, including a lack of dynamic fluid circulation and the inability to simulate cell behavior in vivo. Microfluidic chip technology, which mimics the human microenvironment and provides controlled dynamic fluid cycling, has the potential to solve these questions and generate reliable models of cell migration in vitro. In this study, a microfluidic chip is reconstructed to integrate the bioactive ceramic into the microfluidic chip structure to constitute a ceramic microbridge microfluidic chip system. Migration differences in the chip system are measured. By combining conventional detection methods with new biotechnology to analyze the causes of cell migration differences, it is found that the concentration gradients of ions and proteins adsorbed on the microbridge materials are directly related to the occurrence of cell migration behavior, which is consistent with previous reports and demonstrates the effectiveness of the microfluidic chip model. This model provides in vivo environment simulation and controllability of input and output conditions superior to standardized cell migration detection methods. The microfluidic chip system provides a new approach to studying and evaluating bioactive ceramics. 相似文献
40.