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91.
本文通过“管接头标记自动压印机”原理方案的构思过程,说明产品原理方案设计的功能论方法的一般原理和特点及其应用。 相似文献
92.
姜功建 《烟台大学学报(自然科学与工程版)》1992,(4)
研究用szász-Mirakyan算子S_n(f, x)逼近在(0,+∞)上具有第一类间断点的有界函数了,给出了收敛速度的估计。 相似文献
93.
董大葵 《江西科技师范学院学报》2006,(3):61-64
职校生期刊是随着我国经济建设和职教事业飞速发展而崛起的一支传媒新军。文稿就期刊的办刊方针、刊载内容、版式设计以及服务意识作了探索,凸现了期刊为职校生读者群服务的个性特色。 相似文献
94.
本文给出了Banach空间广义分解定理的一个初等证明,并利用它来证明两个对称不等式.这是首次在Banach空间获得这样的不等式. 相似文献
95.
Structural characterisation of such bio-objects as fibrinogen solution, yeast cells, wheat seeds and bone tissues has been done using two versions of cryoporometry based on the integral Gibbs-Thomson (IGT) equation for freezing point depression of pore liquids and the measurements by 1H NMR spectroscopy (180-200 < T < 273 K) and the thermally stimulated depolarisation current (TSDC) method (90 < T < 273 K) of structured water. The IGT equation was solved using a self-consisting regularization procedure including the maximum entropy principle applied to the distribution function of pore size (PSD). Both methods give clear pictures of changes in the structural characteristics caused, e.g., by hydration and swelling of wheat seeds and yeast cells, coagulation and interaction of fibrinogen with solid nanoparticles in the aqueous media, and the human bone tissue disease. 相似文献
96.
马国伟 《中央民族学院学报》2006,33(1):133-137
“打歌”史称“踏歌”,是一种自娱性的民间歌舞。彝族“打歌”历史悠久、曲调优芙、歌词内容丰富、舞姿活泼多变,并在国内外享有盛名,是彝族文化的重要组成部分,同时也是中华民族优秀的文化遗产之一。在当前世界范围内的现代化进程中,通过各种途径积极保护彝族“打歌”这一传统文艺形式具有十分重要的意义。 相似文献
97.
We consider the isothermal flow through a cylindrical flat chamber, a model of some particular heat exchanger, for which LDV measurements and a numerical simulation have been performed. Experimental results show the establishment of an important vortex zone, the secondary flow extending all along the chamber radius. This observation leads to an expected significant increase of the fluid mixing. Results issued from the numerical simulation appear to be in close agreement with experimental data. Nevertheless, the k–ε model used here must be improved to obtain a better approach near the vortex centre. To cite this article: S. Petitot et al., C. R. Mecanique 330 (2002) 593–599. 相似文献
98.
抓好数学建模竞赛 推动数学教学改革 总被引:5,自引:0,他引:5
本文通过近几年组织数学建模教学和指导学生参加竞赛的实践 ,探索抓好数学建模竞赛 ,促进数学教学改革 ,推动数学素质教育 ,提高人才培养质量的途径、措施和方法 相似文献
99.
The possibilities of controlling the laser beam properties by a deformable mirror introduced into the laser optical cavity
were studied theoretically and experimentally. The experiments were performed under conditions of an industrial high power
transverse flow cw CO2 laser operating with a stable resonator of a folded configuration. A deformable bimorph mirror of a surface profile controlled
by the voltage applied to the mirror electrodes is implemented to the laser system as a back cavity mirror or as a one of
the inner folding mirrors. The near-and far-field characteristics of the laser beam versus the resonator configuration controlled
by the changes of the focal length of the deformable mirror are discussed in the paper. The analysis reveals that the resonator
with an inner deformable mirror is much more sensitive to the mirror curvature variations than the resonator in which the
deformable mirror is used as a back cavity mirror. The presented results show that dynamic and controllable changes in the
resonator properties result in the controlled modification and optimisation of the laser output power and spatial parameters
of the laser radiation. 相似文献
100.
For vertical-cavity surface-emitting lasers (VCSELs) with polarization-rotated feedback, there exist several synchronization
types such as synchronizations between total powers and synchronizations between separate polarization modes. Based on the
two-mode rate equations, we study and compare numerically the performances of different synchronization types. Our results
show that three synchronization types exhibit good performances when their synchronization conditions are satisfied. They
are the complete synchronization between total powers, complete synchronization between x-polarized modes, and generalized synchronization between x-polarized and y-polarized modes. The former two types are sensitive to the injection rate and spontaneous emission, while the third type
is contrary. Synchronization type with the best performance may switch from one to another, with changing of injection rate
and spontaneous emission factor. 相似文献