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101.
新生儿疼痛面部表情识别方法的研究 总被引:3,自引:0,他引:3
针对新生儿的疼痛与非疼痛面部表情识别,提出将Gabor变换和支持向量机(SVM)相结合的分类识别方法.对归一化后的大小为112 pixel×92 pixel的新生儿面部图像进行二维Gabor小波变换,提取出412160维Gabor特征;针对Gabor特征向量维数高、冗余大的特点,采用Adaboost算法作为特征选择工具,去除冗余的Gabor特征,从412160维特征中选取出900维Gabor特征;对选取出的Gabor特征用SVM进行疼痛表情的分类识别.该方法综合运用Gabor特征对于面部表情的良好表征能力、AdaBoost算法的特征选择能力以及SVM在处理少样本、高维数问题中的优势.对510幅新生儿的表情图像进行测试的结果表明,疼痛与非疼痛表情的分类识别率达到85.29%,疼痛与安静表情的分类识别率达到94.24%,疼痛与哭表情的分类识别率达到78.24%. 相似文献
102.
103.
Comparison of tribological properties of CrN, TiCN and TiAlN coatings sliding against SiC balls in water 总被引:1,自引:0,他引:1
Qianzhi Wang Fei Zhou Xiaonan WangKangmin Chen Meiling WangTao Qian Yanxia Li 《Applied Surface Science》2011,257(17):7813-7820
CrN, TiCN and TiAlN coatings were deposited on WC cemented carbide disks using enhanced cathodic arc magnetron sputtering and their topographies and structures were observed and analyzed using scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The friction and wear properties of CrN, TiCN and TiAlN coatings sliding against SiC balls in water were investigated and compared synthetically using ball-on-disk tribometer. The results showed that the CrN/SiC tribopairs showed the lowest friction coefficient of 0.076, while the TiCN/SiC tribopairs displayed the highest friction coefficient of 0.264. For the CrN/SiC tribopairs the specific wear rate of CrN coatings was lowest while that of SiC balls became highest. But for the TiAlN(TiCN)/SiC tribopairs, the specific wear rate of TiAlN coatings was highest while that of SiC balls for the TiCN/SiC tribopairs became lowest. This indicated that the friction and wear behaviors of nitride coatings/SiC balls tribo-systems in water were more strongly influenced by the anti-oxidative ability of tribomaterials in water than by their mechanical properties. 相似文献
104.
逆境胁迫对藻类抗氧化酶系统的影响 总被引:3,自引:0,他引:3
就国内外有关逆境胁迫对藻类抗氧化酶系统的影响研究进行了概述,探讨了温度、重金属、紫外照射等逆境条件下藻类体内抗氧化酶系统各组分的活性变化.分析了藻类的抗逆性强弱与抗氧化酶系统的活性之间存在的联系,发现通常抗逆性强的藻类在逆境胁迫下其抗氧化酶系统活性较强.另外,还介绍了藻类中主要抗氧化酶在分子水平的研究现状,并提出该领域有待进一步探讨的问题. 相似文献
105.
106.
This article focuses on an optimal hedging problem of the vulnerable European contingent claims. The underlying asset of the vulnerable European contingent claims is assumed to be nontradable. The interest rate, the appreciation rate and the volatility of risky assets are modulated by a finite-state continuous-time Markov chain. By using the local risk minimization method, we obtain an explicit closed-form solution for the optimal hedging strategies of the vulnerable European contingent claims. Further, we consider a problem of hedging for a vulnerable European call option. Optimal hedging strategies are obtained. Finally, a numerical example for the optimal hedging strategies of the vulnerable European call option in a two-regime case is provided to illustrate the sensitivities of the hedging strategies. 相似文献
107.
We study the asymptotic of the generalized Bergman kernels of the renormalized Bochner–Laplacian on high tensor powers of a positive line bundle on compact symplectic manifolds. To cite this article: X. Ma, G. Marinescu, C. R. Acad. Sci. Paris, Ser. I 339 (2004). 相似文献
108.
高温胁迫下不同龙须菜品系抗氧化能力的比较 总被引:3,自引:0,他引:3
以龙须菜耐高温新材料07-2、龙须菜良种981及野生型龙须菜3个品系为材料,研究在不同温度条件下(24、28、32℃)其总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-PX)、过氧化物酶(POD)的活性变化,及抗坏血酸(维生素C)、维生素E、可溶性蛋白和丙二醛(MDA)的含量变化.结果表明:高温胁迫条件下,981和07-2的总抗氧化能力均高于野生型,28℃时981上升幅度比野生型高102.35%,07-2比野生型高18.86%;32℃时981比野生型上升幅度高17.87%,07-2则比野生型高73.52%.高温胁迫条件下,无论是酶促抗氧化系统还是非酶促抗氧化系统981和07-2都不同程度地优于野生型.可见,高温胁迫条件下981和07-2与野生型相比具有更强的清除活性氧的能力,表明抗氧化活性指标与龙须菜耐热性有相关性. 相似文献
109.
根据几种复杂外形设计的特点,木文构造了三角形域上S12样条插值曲面,三角形域上的C2超限插值曲面,矩形参数域上C2超限插值曲面和任意四边形域上双三次C1,C2样条插值曲面,给出了一类有效的边界条件确定方法.同时,算法皆已应用到人体外形描述和飞机外形设计中. 相似文献
110.
ABSTRACTObtaining both high hardness and toughness is a challenge in B4C-nano-adhesive composites. Solving the inhomogeneous distribution of nano-adhesives in B4C and forming the chemical bonding at grain boundary is an effective method. Here, we reported that the uniform distribution of titanium diboride (TiB2)-reinforced B4C composites synthesized by high-pressure and high temperature (HPHT). It is found that HPHT sintering can effectively inhibit the grain growth and increase the relative density. Moreover, HPHT sintering can cross high reaction energy barrier and effectively promote the formation of chemical bonding at grain boundary between B4C and TiB2. The optimal hardness and toughness value reach 30.0?±?0.9?GPa and 7.87?MPa·m1/2, respectively. The improvement of hardness and toughness in the final products are ascribed to the strengthening of nanoTiB2 connection of B4C boundary and intergranular fracture mechanism. This work suggests a new way to achieve the uniform distribution of nanoTiB2 in B4C and form the chemical bonding at grain boundary, which is of great significance to the further development of TiB2-reinforced B4C composites with excellent mechanical properties. 相似文献