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关键词： Blood   Principal component analysis   Correlation coefficient   Elements  

摘要： Principal component analysis (PCA) is applied as a powerful tool to identify the possible correlations of different elements and patterns in large collection of blood samples. PCA has been successfully applied to analytical data of Cu, Cd, Li, Mg, Pb and Zn for their possible correlations with each other in 500 blood samples of healthy human subjects. The graphical representation of scores has been used to conceive the relative disparity in large collection of blood samples, while the loadings have been used to explain their any possible relationship among elements. Loadings show a direct correlation between Pb and Cd and negative correlation between Cu and Zn in the blood *** scores suggest 12 samples as outliers. These samples were rejected from the normal blood samples. However, the scores of the rejected blood samples indicate no defined correlation between Pb and Cd and inverse correlation between Cu Zn, Mg -Cd and Cd - Li.

关键词： 社会养老制度   产生和发展   因素分析   效度检验  

摘要： 社会养老制度是依靠什么力量产生和发展起来的？对此，有很多不同的回答进而形成了五种理论观点。本文对此作了归纳和分析，并以几个国家的经验为依据，分别检验了这些理论观点（包括工业发展理论、社会民主理论、新马克思主义理论、新多元化理论、国家中心理论）的效度。笔者认为，单个理论的效度犹如彩虹的不同颜色一样，只有整合在一起才能完整、有效地解释不同国家社会养老保险制度的产生和发展历程，而英国的案例很好地诠释了这个观点。

摘要： 本文拟应用灰色关联度和序列平稳性、协整及Granger因果关系等计量检验方法，利用我国历年环保产值、国内生产总值的相关数据，实证分析环保产业对国民经济的增长的拉动作用及程度。1 环保产业与国内生产总值灰色关联度分析2006年国家环境保护总局联合国家发展和改革委员会和国家统计局公布了《2004年全国环境保护相关产业状况公报》，以及2007年公布的《2006年中国环境产业发展报告》显示：我国环境保护相关产业总体呈现持续稳定的发展态势，环境保护产品领域稳步发展，环境保护服务业有较大进展，资源综合利用和洁净产品领域快速发展。图1 环保产值趋势图图1显示的是从1988年开始国家陆续公布的环保产业产值的趋势图，可以看出，从2000年以后，中国环保产值有显著的提高。灰色关联理论是邓聚龙教授于1982年首先提出的，它是根据事物或因素的时间序列曲线的相似程度来判断其关联程度的。若两条曲线的形状彼此相似，则关联度大，反之，则关联度较小。根据灰色关联度理论，(1)选取环保产业产值（1988年至2006年）作为参考数列，国内生产总值（1988年至2006年）的值（按2000年价格进行调整）作在比较数列；(2)n=19，经计算可得，环保产业与国内经济增长灰色关联度为r=0.79337，该值表明环保产业产值与国内生产总值两条曲线的形状相似程度较高，关联度大。2 计量检验实证研究2.1 数据说明本文的检验涉及两个时间序列——国内生产总值、环保产业产值。其中，国内生产总值取1988～2006年，因为数据为当年价格，为了保证检验结果更有效，将其按2000年的价格进行调整；环保产业产值，因为国家环保相关部门不是每年出《全国环境保护相关产业公报》，能查到的相关环保产业数据仅仅有1988年、1993年、1997年、2000年以及2004年，所以，本文中的其他数据是参照历年《中国统计年鉴》并根据趋势平滑而得，并作相应调整。2.2 单位根检验本文使用的数据是时间序列，故需检验时间序列的稳定型。从上面的图2、3趋势图，我们可以看出国内生产总值和环保产值的时间序列是随时间的变化而变化的。且呈指数增长的趋势，所以，这里将两组序列进行指数变化。

关键词： Feature Selection   Hyperspectral   Genetic Algorithm   Supported Vector Machine  

摘要： The high-dimensional feature vectors of hyper spectral data often impose a high computational cost as well as the risk of over fitting when classification is performed. Therefore it is necessary to reduce the dimensionality through ways like feature selection. Currently, there are two kinds of feature selection methods: filter methods and wrapper methods. The form kind requires no feedback from classifiers and estimates the classification performance indirectly. The latter kind evaluates the goodness of selected feature subset directly based on the classification accuracy. Many experimental results have proved that the wrapper methods can yield better performance, although they have the disadvantage of high computational cost. In this paper, we present a Genetic Algorithm (GA) based wrapper method for classification of hyper spectral data using Support Vector Machine (SVM), a state-of-art classifier that has found success in a variety of areas. The genetic algorithm (GA), which seek to solve optimization problems using the methods of evolution, specifically survival of the fittest, was used to optimize both the feature subset, i.e. band subset, of hyper spectral data and SVM kernel parameters simultaneously. A special strategy was adopted to reduce computation cost caused by the high-dimensional feature vectors of hyper spectral data when the feature subset part of chromosome was designed. The GA-SVM method was realized using the ENVI/IDL language, and was then tested by applying to a HYPERION hyper spectral image. Comparison of the optimized results and the un-optimized results showed that the GA-SVM method could significantly reduce the computation cost while improving the classification accuracy. The number of bands used for classification was reduced from 198 to 13, while the classification accuracy increased from 88.81% to 92.51%. The optimized values of the two SVM kernel parameters were 95.0297 and 0.2021, respectively, which were different from the default v

关键词： Chemometrics   Chili sauce   Principal component analysis   PCA   Cluster analysis  

摘要： As a preliminary work on the possibility of separating classes of chili sauces based on taste or customer preferences, organic compounds from different kinds of chili sauces of various brands were separated and analyzed by gas chromatography/mass spectrometry (GC/MS). It was found that these organic compounds do form a basis for separation of different types of sauces. The similarity and dissimilarity of chromatograms due to the organic composition of the chili sauces were explored by multivariate pattern recognition techniques based on cluster analysis (CA) and principal component analysis (PCA). Both CA and PCA results exhibit four linearly separable classes, namely general sauces, hot sauces, sauces with benzoic acid and sauces with garlic. It was concluded that by using chosen retention peaks in the chromatograms of various sauce samples as multivariate features, CA and PCA can be successfully used to reveal the natural clusters existing in chili sauces according to their organic composition.

关键词： 微生物检验   医院感染   监测   控制  

摘要： 医院感染监控工作已成为医院质量管理工作中的重要组成部分,在医院感染监控工作中临床微生物实验室则担负着主要的任务.本文就临床微生物实验室在医院感染监控总的作用作一阐述.

关键词： electron density distribution   high pressure   single-crystal diffraction study   maximum entropy method   charge transfer   electron-lattice interaction  

摘要： Single-crystal diffraction studies have been conducted up to 50 GPa using synchrotron radiation with diamond anvil cells. Electron density distribution (EDD) analysis has been performed by the maximum entropy method (MEM) using single-crystal diffraction intensity data in order to elucidate the electric conductivity change, electronic state, charge transfer and charge disproportionation with changing pressure. The MEM calculation based on F-obs(h k l) shows a much more precise EDD than the difference Fourier synthesis based on F-obs(h k l) - F-calc(h k l). The radial distribution of the density indicates the enhancement of the electron localization with increasing pressure. The anisotropy in the electric conductivity of FeTiO3 ilmenite has been clarified by the EDD analysis. The MEM analyses clarify the structure transition from the cubic to tetragonal structure of Fe2TiO4 ulvospinel. The Jahn-Teller distortion is induced from Fe2+ (3d(6)) at the tetrahedral site at low temperature and high pressure (HP). The electron density analyses at HPs also elucidate the structure changes of KNbO3, PbTiO3 and BaTiO3 ferroelectrics. The static dipole moment can be evaluated by the observed effects and deformation of the site symmetry.

关键词： 施工企业   合同管理   效率   组织结构形式  

摘要： 合同管理不仅影响到合同能否顺利实施,而且决定了施工企业的盈利能力。合同管理的效率取决于项目管理的组织形式。而合适的组织形式的选择取决于组织的目标和任务。合同管理是一项复杂的动态管理工作。为了提高合同管理的效率就必须对项目管理组织形式进行改进,使之适合合同管理的需要。

关键词： 临床检验   肾综合征出血热   早期临床特征   特征分型   注意事项  

摘要： 肾综合征出血热是由汉坦病毒所致的一种自然疫源性疾病,是我国除病毒性肝炎之外受害最大的病毒性传染病.由于该病早期临床表现复杂、近年不典型病例增多、新疫区不断增多、没有特异性诊断技术、临床医生认识不足等因素,误诊误治病例逐年增多,常因此导致延误治疗甚至病情恶化.笔者现将临床检验对早期诊断肾综合征出血热的指导作用的体会介绍如下,以供同行参考,具有一定借鉴意义.

关键词： 合同形式   发展规律   比较法  

摘要： 本文用历史方法和比较法的方法,分析合同形式的发展历程及其背后的原因。揭示出合同形式经历由强制主义——意思主义——有限强制主义的演变过程,以期能给我国相关立法提供借鉴。