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131.
提出了一种基于多视角的人体行走状态分析方法.首先,利用基于自适应背景更新的背景差分法检测出运动人体;其次,利用4向链码提取人体上半身质心运动轨迹的周期;最后,通过训练不同运动状态的周期得到对应的模糊集,根据隶属度函数判别慢走、走和跑3种运动状态.实验结果表明,该方法能够准确分析人体运动速度并判断其运动状态,并且对背景噪声、视角变化有良好的鲁棒性.  相似文献   
132.
在半球形介质以及球形界面一侧含有两种不同介质的静电问题中,由于勒让德多项式在这类区间上的非正交性,应用半球区间积分方法得到的电势一般是以无穷级数的形式给出的,它的收敛性通常由于实际问题的复杂性而是假定的.为研究此方法所得解的收敛性,应用此方法求解球壳内含两种不同介质的静电问题,并将所得电势的级数解与它的精确解相比较,结果二者完全一致,表明该方法对求解此类问题的有效性,同时也给出球壳静电问题一个全新的解法.  相似文献   
133.
求解背包问题的病毒协同进化粒子群算法   总被引:2,自引:1,他引:1  
为提高粒子群算法的搜索性能,提出一种基于病毒进化理论的改进离散粒子群算法:病毒协同进化粒子群算法.在粒子群中引入生物病毒机制和宿主与病毒基于感染操作的思想,病毒采用与粒子等长的编码方式,执行反向代换、结合等操作,利用病毒的水平感染和垂直传播能力较好地维持个体的多样性和对解空间的局部搜索能力.通过解决背包问题对算法进行验证,仿真表明所提算法搜索性能优于遗传算法、模拟退火及标准粒子群等其他算法.该算法能有效求解背包问题等NP难题.  相似文献   
134.
以环氧树脂为基体树脂,向其加入固化剂、抗氧化剂、固化促进剂,并在适当的温度下固化。以灌封料的弯曲强度为指标,通过正交试验确定了环氧树脂固化工艺的最佳条件是:环氧树脂为100 g,固化促进剂用量为0.7 g,抗氧化剂为0.3 g,固化温度为140℃,固化剂为96.3 g。在此条件下,环氧树脂灌封料的弯曲强度可以达到28.3 MPa。  相似文献   
135.
广东某新建1 000 MW超超临界发电机组是上海锅炉厂有限公司引进美国AISTOM技术设计的首台Ⅱ型锅炉.对于高加至省煤器入口高压给水管道的规格设计,由于设计院和锅炉厂二者设计压力等级不同,导致这部分高压给水管道与锅炉主给水门规格存在较大差异,给安装接口工作带来极大的障碍,被迫采用大小头来过渡,造成不必要的浪费和安全隐患.对该管段的设计进行了初步探讨.  相似文献   
136.
Resin adsorption technique with XAD-8 and XAD-4 was used to characterize the raw water from Erlong reservoir in Jilin province of China. The NOM chemical composition sequences of four organic fractions in the raw water,from high to low,are fulvic acid (FA) fraction,hydrophilic non-acid (HPINA) fraction,hydrophilic acid (HPIA) fraction,and humic acid (HA) fraction. Experimental results show that FA is the main precursor of THMFP among the four organic fractions. However,HA or hydrophobic acid exhibits the highest chlorination activity in forming THMs. It is also found that the value of FI/DOC or SUVA and the specific THMFP have better positive correlation. It is implied that certain source water has unique nature of NOM and DBPs.  相似文献   
137.
A process was proposed based on the combination of chemical and physical activation for the production of activated carbons used as the electrode material for electric double layer capacitor (EDLC). By material characterization and electrochemical methods, the influences of the activitation process on the specific surface area, pore structure and electrochemical properties of the activated carbons were investigated. The results show that specific surface area, the mesopore volume, and the specific capacitance increase with the increase of the mass ratio of KOH to char (m(KOH)/m(char)) and the activation time, respectively. When m(KOH)/m(char) is 4.0, the specific surface area and the mesopore volume reach the maximum values, i.e. 1 960 m2/g and 0.308 4 cm3/g, and the specific capacitance is 120.7 F/g synchronously. Compared with the chemical activation, the activated carbons prepared by chemical-physical activation show a larger mesopore volume, a higher ratio of mesopore and a larger specific capacitance. Foundation item: Project(2007BAE12B01) supported by the National Key Technology Research and Development Program of China  相似文献   
138.
Model test of the cutting properties of a shearer drum   总被引:1,自引:1,他引:0  
According to similarity theory, we carded out a dimensional analysis of the shearer drum correlation parameters and built similarity criteria. Based on these, similarity models of shearer drums were developed. Simultaneously, based on an estab-lished cutting testbed of the coal and rock, cutting tests of different pick arrangements of the drum models were carried out, where the compressive strength of the analogous cutting material was 2.48 MPa and the drum rotary speed 67.5 r/min. The variance, the mean values, maxima and mean maxima of the torque load were analyzed for different type drum models. Moreover, the relation-ships between the type of pick arrangements and the cutting lump coal percentage were studied. The results indicate that the load fluctuation of the sequence drum is larger than that of the punnett square drum in the cutting process and the lump coal percentage and economic benefits of the sequence drum are inferior to the punnett square drum. We conclude that the punnett square drum is superior to the sequence drum.  相似文献   
139.
Non-liner wave equation inversion, wavelet analysis and artificial neural networks were used to obtain stratum parame-ters and the distribution of thin coal seams. The lithology of the water-bearing/resisting layer in the Quaternary system was also predicted. The implementation process included calculating the well log parameters, stratum contrasting the seismic data and the well logs, and extracting, studying and predicting seismic attributes. Seismic inversion parameters, including the layer velocity and wave impedance, were calculated and effectively used for prediction and analysis. Prior knowledge and seismic interpretation were used to remedy a dearth of seismic data during the inversion procedure. This enhanced the stability of the inversion method. Non-linear seismic inversion and artificial neural networks were used to interpret coal seismic lithology and to study the wa-ter-bearing/resisting layer in the Quaternary system. Interpretation of the 1-2 m thin coal seams, and also of the wa-ter-bearing/resisting layer in the Quaternary system, is provided. The upper mining limit can be lifted from 60 m to 45 m. The pre-dictions show that this method can provide reliable data useful for thin coal seam exploitation and for lifting the upper mining limit, which is one of the principles of green mining.  相似文献   
140.
给出了两个关于矩阵域ιpA-(1≤p<∞)的哈恩性质的结果,从而推广了近期的类似结果.  相似文献   
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