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101.
102.
The classical two-film model for mass transfer between two fluid phases can only be used to describe the steady state mass transfer mechanism. Both the penetration and the film-penetration model are also valid solely when only one diffusion boundary layer exists at the interface between the phases. With a view to surmounting the limitations of the above models a new model has been developed for the mass transfer between two fluid phases with two diffusion boundary layers at the interface. The new model is based on the two-film concept and the Danckwerts distribution function, and is also able to simulate the unsteady state mass transfer mechanism between two fluid phases with two different boundary layers. 相似文献
103.
Qian Huang 《Thin》1991,12(5):355-372
The conventional approaches for stress analysis of composite laminates have encountered discontinuity problems. In this paper, the C1 continuity of displacements in the in-plane directions and C0 continuity of displacement along the thickness direction are discussed. Also, the global continuity of transverse stresses and local continuity of in-plane stresses are examined. Then, the formulations of stress analysis in both differential equation form and variational functional form are presented. 相似文献
104.
105.
106.
Improvements in the performance of silicon photovoltaic cells for solar applications are adapted for nonsolar photovoltaic applications. Improved monochromatic light efficiencies above 45% are reported including efficiencies close to 40% for relatively long-wavelength (1.064 μm) light as produced by neodymium-doped yttrium-aluminum garnet (Nd:YAG) lasers 相似文献
107.
108.
阐述了邢台矿区的水文地质特征,影响下组煤开采的主要充水因素,重点总结了公司下组煤带压开采的实践经验、技术路线和关键的防治水技术。 相似文献
109.
Transformations in machining. Part 1. enhancement of wavelet transformation neural network (WT-NN) combination with a preprocessor 总被引:2,自引:0,他引:2
X. Wang P. Chen I.N. Tansel Yenilmez A 《International Journal of Machine Tools and Manufacture》2006,46(1):36-42
Properly selected transformation methods obtain the most significant characteristics of metal cutting data efficiently and simplify the classification. Wavelet Transformation (WT) and Neural Networks (NN) combination was used to classify the experimental cutting force data of milling operations previously. Preprocessing (PreP) of the approximation coefficients of the WT is proposed just before the classification by using the Adaptive Resonance Theory (ART2) type NNs. Genetic Algorithm (GA) was used to estimate the weights of each coefficient of the PreP. The WT-PreP-NN (ART2) combination worked at lower vigilances by creating only a few meaningful categories without any errors. The WT-NN (ART2) combination could obtain the same error rate only if very high vigilances are used and many categories are allowed. 相似文献
110.
Ten-user truly asynchronous gigabit OCDMA transmission experiment with a 511-chip SSFBG en/decoder 总被引:8,自引:0,他引:8
Hamanaka T. Xu Wang Naoya Wada Nishiki A. Kitayama K. 《Lightwave Technology, Journal of》2006,24(1):95-102
A ten-user truly asynchronous gigabit coherent-optical-code-division-multiple-access (OCDMA) transmission was experimentally demonstrated without using any timing coordination. The enabling technologies are a record-length 511-chip superstructured-fiber-Bragg-grating (SSFBG) en/decoder and a supercontinuum (SC)-based optical-thresholding technique to significantly suppress the signal interference beat noise as well as the multiple-access-interference (MAI) noise. 相似文献