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71.
马田系统是一种新的模式识别技术,是将田口式信噪比的试验设计方法的一整套思想应用到模式识别的特征变量选择问题上,并通过构建正常样品的基准空间,应用马氏距离值进行样品类别的识别.探讨了马田系统的基本原理,并应用MTGS模型方法对费希尔关于鸢尾花类型的判别问题进行研究,显示了马田系统方法的良好判别分类效果. 相似文献
72.
陈玉娟 《数学物理学报(A辑)》2010,30(2):386-396
该文采用弱上下解方法和正则化技巧,研究了一类非局部退化抛物型方程组解的爆破和整体存在性,给出了爆破指标,并对非退化情形m=n=1,p_1=q_1=0,p_2q_21给出了一致爆破速率. 相似文献
73.
The variational method is used to obtain some existence theorems for periodic solutions of second order systems with or without impulsive under weak sublinear growth conditions. 相似文献
74.
Xiangjian Xu 《Applied mathematics and computation》2010,217(5):1944-1948
In this paper, we present a fast algorithm for solving Symmetric penta-diagonal systems. We give the feasibility and Stability analysis of the algorithm. Moreover, parallel computations can be implemented in the algorithm. The numerical examples verify the efficiency of the algorithm. 相似文献
75.
《Journal of magnetism and magnetic materials》2002,247(1):6-14
Mean-field theory based on Heisenberg model is used to investigate the magnetic and magnetoelectric properties at a finite temperature in the A-type antiferromagnetic lattice, in which we consider that an applied electric field can generate a bulk magnetic moment. We have calculated the magnetic moment, magnetic susceptibility and magnetoelectric susceptibility as a function of temperature for A-type antiferromagnetic system. It is demonstrated that an applied electric field together with the coupling parameter has an effect on the magnetic ordering behavior. Our results are almost consistent with those of spin-wave theory within the range of low temperature. 相似文献
76.
《Journal of membrane science》2002,207(2):265-272
Protein binding of drug is responsible of ineffectiveness of conventional hemodialysis. The aim of the present study was to investigate the potential of electrodialysis, i.e. the transport of charged solutes through a membrane under the influence of an external electric potential, to increase the clearance of phenytoin, i.e. a model albumin-bound drug from human serum in vitro.Electrodialysis was performed through cellulose triacetate membrane mounted onto electrodialyser built in-house which separated: (a) saline solution, (b) 4% albumin saline solution or (c) human serum and dialysate compartments. The electric current density between both electrodes placed into donor (cathode) and dialysate (anode) compartments was settled to 0.79 mA/cm2 for 3 h at 37 °C.Recovery of phenytoin in dialysate from either (a) saline solution or (b) 4% albumin saline solution was significantly higher than that obtained by classical dialysis ((a): 42% versus 24%; (b): 30% versus 6%). In human serum, the effectiveness of electrodialysis was appreciated by the unbound phenytoin clearance, which was about twice higher than in dialysis (0.22 ml/h versus 0.12 ml/h). However, the removed fraction of 10% in the human serum could just reflect the usual unbound phenytoin. Consequently, the impact of electrodialysis on the protein binding was not affirmed, but the ability of this technique to eliminate shortly free drug was clearly demonstrated. Electrodialysis would be a promising improvement of hemodialysis for the elimination of ionized drugs from human blood. 相似文献
77.
Influence of atmospheric pressure plasma treatment time on penetration depth of surface modification into fabric 总被引:1,自引:0,他引:1
In order to determine the relationship between the treatment duration of atmospheric pressure plasma jet (APPJ) and the penetration depth of the surface modification into textile structures, a four-layer stack of polyester woven fabrics was exposed to helium/oxygen APPJ for different treatment durations. The water-absorption time for the top and the bottom sides of each fabric layer was reduced from 200 s to almost 0 s. The capillary flow height for all fabric layers in the stack increased linearly with the treatment duration but the rate of increasing reduced linearly with the fabric layer number. A model for the capillary flow height as a function of treatment duration and the layer number was established based on the experimental data and the maximum penetration depth of the APPJ was predicted for the polyester fabric. The improved wettability of the fabrics was attributed to the enhanced surface roughness due to plasma etching and the surface chemical composition change due to plasma-induced chemical reaction as detected by scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. The surface roughness and the surface chemical composition change diminished as the fabric layer number increased. 相似文献
78.
M.R. Shi F. Xu Ke Yu J.H. Fang X.M. Ji 《Applied Physics A: Materials Science & Processing》2008,90(1):113-117
In2O3 particles with different morphology were controllably synthesized on silicon substrates by thermal evaporation of In grains
at 900 °C. The structure and morphology of the In2O3 particles were evaluated using X-ray diffraction, and scanning and transmission electron microscopies. The evolution in shapes
as the ratio of {100} relative to {111} increases is clearly observed. The photoluminescence spectrum of the obtained In2O3 structures exhibits UV emission centered at about 378 nm and wide-band emission covering the green and orange regions with
three peaks around 525, 572, and 604 nm.
PACS 81.05.Hd; 81.07.Bc; 81.16.-c; 61.46.-w; 81.40.Gh 相似文献
79.
Potential Analysis - The purpose of this paper is to provide necessary and sufficient conditions of the boundedness for singular integrals on the local Hardy space and its dual. Particularly the... 相似文献
80.
《印度化学会志》2023,100(4):100960
Disperse Red 177(9a), Disperse Red 343(9b), Disperse Blue 165(9c), Disperse Blue 165.1(9d), Disperse Blue 366(9e), and Disperse Blue 148(9f) were examined in the solvent. During silicon nanomicelle dyeing, we employed 9(a–f) azo disperse dyes on polyester. On polyester fabric, dye 9(a–f) offers equal washing, light, and rubbing fastness in both the conventional and silicone nanomicelle techniques. The dye can now be transported directly into the fibre core without the use of auxiliary dyes owing to the reduction in the particle size of azo dyes, which is made possible by nanoemulsions superior dispersion. The levelling property of the dispersed dye is enhanced by the dyeing process. When both techniques are applied, the lightfastness properties of all dyes are improved. It provides a very good to outstanding protection factor for textile materials. These 9(a–f) azo disperse dyes have moderate to outstanding photostability, net electrophilicity index, and lightfastness. 相似文献