融合Gabor小波和双层LLE的人耳图像识别

针对局部线性嵌入(LLE)算法易受偏转角度和近邻选取的影响,提出了一种双层LLE(DLLE)的人耳图像识别方法,并结合Gabor小波和DLLE提出了GDLLE。DLLE首先计算各样本与每类样本中心的欧氏距离,再把欧氏距离最小的K类所有样本作为LLE的近邻,提取出鉴别特征,最后由最近近邻分类器对鉴别特征进行分类。在USTB3人耳图像库上的实验结果表明,本文提出DLLE能够减小偏转角度和近邻对LLE算法的影响,结合Gabor小波后进一步改善了算法的识别率。     

粗略不相似度量及其在层次聚类中的应用

局部结构特征在数据分析过程中具有重要的作用.为获得简单有效的数据集局部结构化特征检测方法,本文结合重采样误差分析和传统的近邻选择方法提出了一种检测局部结构特征的方向一致性度量—粗略不相似性度量.该度量是一种优化的近邻选择方法,不仅考虑了传统的欧氏距离排序,而且考虑了局部方向结构特征.因其计算和存储复杂度小以及具有优越的结构检测性能,可应用于无监督学习形成一种层次化的子图聚类算法—RDClust,与经典聚类算法相比,其优势在于:一是计算复杂度较小,是近似线性算法;二是无需对类的形状和分布形式做任何的假设,可自动体现数据集的局部结构;三是有一个近邻参数,且该参数对结果较鲁棒.在人工和真实数据集上的实验显示了新的度量方式应用于新算法的优越性能.     

流形核与LPP相结合的毛杆折痕识别方法

针对毛杆折痕难以检测问题,将非线性流形的思想引入到折痕识别领域。提出运用流形核函数与局部保持投影相结合的方法进行毛杆特征提取。首先基于区域图像构造协方差矩阵作为图像特征,利用仿射不变度量作为样本点的距离测度。然后通过定义的黎曼核函数选择流形上的近邻点,使得近邻点的选择符合数据呈非线性流形的假设,并结合数据类别信息构造相应的核矩阵。最后利用局部保持投影算法对毛杆图像进行降维。实验结果表明,本文算法能够有效克服光照不均和残余绒毛等外部因素影响,具有较好的稳健性和较高的识别率。     

基于信息特征耦合夹角一致性规则的图像匹配算法

目的针对当前基于灰度特征的图像匹配算法在遇到匹配图像存在较大的光照变换时,会引起较多的误匹配和漏匹配等问题,提出一种基于信息特征耦合夹角一致性规则的图像匹配算法。方法首先,利用Forstner算子来检测图像的特征点,接着用Hessian矩阵最大特征值与其最小的特征值做比值计算,优化Forstner算子的检测特征点。然后,以特征点为原点,构建极坐标系,将特征点的邻域进行分割。再利用信息熵模型求取每个分割块中的信息特征,以生成特征描述子。最后,利用特征描述子构造距离模型,搜索指定特征点的最近邻特征点和次近邻特征点,并通过距离比值方法完成特征点的匹配。通过匹配特征点之间形成的夹角,建立夹角一致性规则,对匹配特征点的可靠性进行度量,剔除错误匹配特征点,从而完成图像匹配。结果实验结果显示,与当前图像匹配算法相比,所提图像匹配算法图像在旋转角度10?~100?范围内,识别率为94.6%~88%,平均识别时间为5.48 s,具有更高的匹配精度与鲁棒性。结论所提算法具有较高的检测精度,在印刷防伪与信息安全等领域具有较好的应用价值。     

相关流形距离在转子故障数据集分类中的应用方法

针对故障特征属性值域之间存在着一定相关性导致准确分类困难的问题,提出一种能够考虑相关系数影响作用的转子故障数据集分类方法;该方法是将相关流形距离的边界Fisher分析(Correlation Manifold Distance Marginal Fisher Analysis,CDMFA)与相关流形距离的K-近邻(Correlation Manifold Distance K-Nearest Neighbor,CDKNN)分类器概念相结合在一起的结果。首先,将振动信号集合转换成多域、多通道高维故障特征数据集;然后,通过CDMFA将融合相关系数的相关流形距离用于度量数据样本间的近邻与权值,据此能更好地反映高维数据间的相似性关系,提取出能使类间距离趋大的低维特征子集;最后,将得到的低维特征子集输入到CDKNN分类器中进行故障模式辨识。用一个双跨度转子系统数据集与仿真数据集对所提出的方法进行了验证。结果表明:本方法降维效果良好,可获得更高的故障分类准确率。研究发现,采用相关流形距离作为信息测度的故障数据分类方法能更真实地揭示出高维特征间的几何结构关系;该方法可为高维故障数据集的特征属性约简与分类,提供降低数据规模的理论参考依据。     

近邻概率距离在旋转机械故障集分类中的应用方法

针对多种故障类型的特征属性相互交叉导致故障难以辨识的问题,提出一种考虑相邻点之间成为近邻点概率的新度量函数。将新提出的近邻概率距离(Nearby Probability Distance,NPD)应用于局部保持投影算法(Locality Preserving Projection,LPP)与K-近邻(K-Nearest Neighbor,KNN)分类器中,提出基于近邻概率距离的局部保持投影算法(Nearby Probability Distance Locality Preserving Projection,NPDLPP)与基于近邻概率距离的K-近邻(Nearby Probability Distance K-Nearest Neighbor,NPDKNN)分类器;首先通过时域、频域特征提取方法,将振动信号转化为高维特征数据集,然后通过NPDLPP将高维数据集降维到低维空间,最后将降维得到的低维敏感特征集输入到NPDKNN中进行模式识别;用一个双跨度转子系统的振动信号集合进行验证,证明了所提出的降维算法效果明显,它能够达到各个故障类型更好分离。研究表明,新提出的近邻概率距离较传统的欧式距离测度更能最小化类内散度,最大化类间分离度。     

多个激活度量相结合的小波图像融合方法

在小波分解的基础上,将小波系数绝对值与局部能量二个激活度量相结合,提出了一种新的小波图像融合算法.根据二幅源图像在同一分解层及同一方向上相同位置的小波系数绝对值之间和局部能量之间出现的4种不同组态,采取选择和加权平均方法确定融合图像的小波系数.实验结果表明新算法具有较好的融合效果.     

基于局部质心均值最小距离鉴别投影的旋转机械故障数据降维分析研究

针对旋转机械故障特征集非线性强、维数过高导致分类困难的问题,提出一种基于局部质心均值最小距离鉴别投影（Local Centroid Mean Minimum?distance Discriminant Projection,LCMMDP）的故障数据集降维算法。该算法在考虑样本的内聚性和分离性的同时,能够保持样本局部几何结构信息,反映样本与局部质心均值之间的近邻关系。从多个角度提取机械振动信号的混合特征,构建原始高维特征集,通过 LCMMDP 提取出低维敏感特征子集,利用改进的基于局部均值与类均值的 k?近质心近邻分类算法（k?nearest Centroid Neighbor Classification Based on Local Mean and Class Mean,KNCNCM）进行故障模式识别。所提方法集成了 LCMMDP 在维数约简和 KNCNCM在模式识别的优势,可得到较高的故障识别准确率。分别使用一个双转子系统数据集和仿真数据集验证了该方法的有效性。     

基于最近邻搜索耦合近邻损耗聚类的图像伪造检测算法

目的为了解决当前图像伪造检测算法在对图像进行伪造检测时,主要依靠全局搜索的方式来完成特征点匹配,导致其检测效率较低,且在对复杂伪造图像进行检测时,易出现检测精度不高和检测错误的不足。方法提出基于最近邻搜索耦合近邻损耗聚类的图像伪造检测算法。首先引入积分图像的方法,对图像进行预处理,借助Hessian矩阵行列式来提取特征点。利用特征点构建圆形区域,通过求取圆形区域内Haar小波响应获取特征点的特征描述符。然后通过特征描述符建立KD树索引,利用最近邻搜索方法代替SURF中全局搜索的方法,对SURF进行改进,完成特征点的匹配。最后,利用特征点间的近邻关系求取近邻函数值,通过近邻函数值对特征点进行聚类,完成图像的伪造检测。结果实验结果显示,与当前图像伪造检测算法相比,所提算法具有更高的检测效率以及更高的检测正确度。结论所提算法具备较高的检测精度,在印刷防伪与信息安全等领域具有较好的应用价值。     

等距映射和局部线性嵌入算法集成的转子故障数据集降维方法

经数据分析途径实现机器智能的故障决策引发出了关于故障数据集的降维问题。通过将等距映射算法(Isometric Mapping,ISOMAP)、局部线性嵌入(Locally Linear Embedding,LLE)算法的优缺点进行互补,提出一种适用于非线性数据集降维的核框架下等距映射与局部线性嵌入相结合的KISOMAPLLE算法。该算法能够同时满足全局距离保持性和局部结构保持能力的数据降维基本要求。用典型的人工数据集和转子故障数据集进行的降维验证结果表明,该算法能够继承ISOMAP、LLE两种算法的各自优良性能,具有能够显著提高典型非线性数据集分类精度的性能。     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.     

Mechanism Study on the Wear of CrAlTiN Coated High-Speed Steel Twist Drills Under Dry Cutting Conditions

As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.     

Study on Bond Ability of Arc-Spraying Coatings with Different Surface Pretreatment on Cast-Iron

Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.     

Structural Characteristics of TiO2 Ceramic Coating by Micro-Plasma Oxidation

TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.     

Evaluation of fatigue life of steel using steel grain size

The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase.