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关键词： Soil pollution   Kohonen neural networks   Self-organizing maps   CART   PRINCIPAL-COMPONENTS-ANALYSIS   SELF-ORGANIZING MAPS   PROCRUSTES ROTATION   REGRESSION TREES   DECISION-SUPPORT   PREDICTION  

摘要： Kohonen neural networks, or Self-Organizing Maps (SOMs), were used to study the data sets generated in a survey of soil pollution along a four-season study. Each sampling season comprised 89 road soil samples and 12 analytical variables: namely, nine heavy metals (Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, and Zn) and three physicochemical parameters (loss on ignition, pH and humidity). The SOMs provided a rapid and intuitive means to recogniz3e four different groups of samples: roadside of a highway, highway transects, roadside of a main avenue and urban gardens. They became defined essentially by the physical characteristics of the sampling sites and by the intensity of the road traffic. In order to simplify the chemical understanding of the patterns defining the different groups of samples, to avoid noisy and/or redundant variables and to reduce the time required to develop a suitable SOM, the usefulness of a previous variable selection step using CART. Classification and Regression Trees, was investigated. (C) 2010 Elsevier B.V. All rights reserved.

关键词： CANCER CLASSIFICATION   PREDICTION   BINARY  

摘要： Background: The use of gene expression profiling for the classification of human cancer tumors has been widely investigated. Previous studies were successful in distinguishing several tumor types in binary problems. As there are over a hundred types of cancers, and potentially even more subtypes, it is essential to develop multi-category methodologies for molecular classification for any meaningful practical application. Results: A jackknife-based supervised learning method called paired-samples test algorithm (PST), coupled with a binary classification model based on linear regression, was proposed and applied to two well known and challenging datasets consisting of 14 (GCM dataset) and 9 (NC160 dataset) tumor types. The results showed that the proposed method improved the prediction accuracy of the test samples for the GCM dataset, especially when t-statistic was used in the primary feature selection. For the NCI60 dataset, the application of PST improved prediction accuracy when the numbers of used genes were relatively small (100 or 200). These improvements made the binary classification method more robust to the gene selection mechanism and the size of genes to be used. The overall prediction accuracies were competitive in comparison to the most accurate results obtained by several previous studies on the same datasets and with other methods. Furthermore, the relative confidence R(T) provided a unique insight into the sources of the uncertainty shown in the statistical classification and the potential variants within the same tumor type. Conclusion: We proposed a novel bagging method for the classification and uncertainty assessment of multi-category tumor samples using gene expression information. The strengths were demonstrated in the application to two bench datasets.

关键词： 微生物学技术   实验室人员   微生物敏感性试验   医院感染   感染控制  

摘要： 目前,导致感染的新病原体不断出现,传统的病原体出现了新问题[1],不仅给临床治疗带来了困难,也向实验诊断提出了挑战.本文重点探讨如何更好地发挥临床微生物检验工作者在医院感染控制中的作用.

关键词： 叉车   充气轮胎   花纹深度  

摘要： 叉车轮胎性能影响叉车使用的安全性,本文主要就叉车中使用较多的充气轮胎的性能、轮胎花纹和花纹深度的研究分析,以及结合叉车的检验规程的对充气轮胎的要求,谈谈叉车定期检验中的注意点。

关键词： 检验科   医院   感染  

摘要： 本文就检验科在医院感染控制工作中的相关作用展开了探讨。

关键词： 备用信用证   受益人   开证行   银行保函   担保函  

摘要： 银行保函和备用信用证作为国际结算和担保的重要形式,都是为了解决交易双方因缺乏了解和信任给交易达成和合同履行造成一定障碍的问题,而由信誉卓著的银行以及其他金融机构作为担保人开立的,保证申请人履行双方签订的有关商务合同或其他经济合同项下的某种责任或义务。

关键词： 计价货币选择   交易成本   市场需求   工具货币   宏观经济政策  

摘要： 计价货币的选择是促进一国货币实现国际化的重要因素。本文在对主要研究进展进行综述的基础上,力图从国际经济贸易的交易成本、商品的海外市场需求、工具货币的选用和宏观经济政策的实施几个方面对货币计价的理论进行一个全方位的梳理,以期对人民币国际化的相关研究做出一定程度的理论参考。

关键词： 智能包装   应用   分类   智能材料   包装材料   信息收集   包装系统   化管理  

摘要： 一、什么是智能包装 随着智能材料不断发展，它的应用范围拓展到了包装，于是出现了“智能包装”的概念。所谓智能包装，是指利用新型的包装材料、结构与形式对商品的质量和流通安全性进行积极干预与保障；利用信息收集、管理、控制与处理技术完成对运输包装系统的优化管理等。

关键词： 分析前   标本采集   检验结果   重要作用  

摘要： 随着医学检验的不断发展及分析前对检验结果的重要影响,护士对检验工作的影响越来越大,护士的综合素质有时直接决定着检验分析的结果。因而应重视和加强护士在各种检验标本的采集、留取、保存和运输等检验分析前各环节中的培训。