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基于Fisher分和支持向量机的特征选择算法 被引量:8
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作者 张润莲 张昭 +1 位作者 彭小金 曾兵 《计算机工程与设计》 CSCD 北大核心 2014年第12期4145-4148,4190,共5页
网络入侵数据集中存在的大量冗余和噪声特征严重影响检测系统的性能。针对该问题,提出一种基于Fisher分和支持向量机的入侵特征选择算法。通过对各维特征的Fisher分值排序,结合支持向量机分类算法,建立特征分类模型,筛选出具有最高检测... 网络入侵数据集中存在的大量冗余和噪声特征严重影响检测系统的性能。针对该问题,提出一种基于Fisher分和支持向量机的入侵特征选择算法。通过对各维特征的Fisher分值排序,结合支持向量机分类算法,建立特征分类模型,筛选出具有最高检测率与误码率比值的最优特征组合。仿真结果表明,该算法筛选出的特征组合具有较高的检测率和较低的误码率,有效降低了检测系统的建模时间和测试时间,提高了系统性能。 展开更多
关键词 入侵检测 fisher分 支持向量机 特征选择 数据标准化
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Fisher最优分割法在星星哨水库汛期分期划分中的应用 被引量:8
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作者 丁元芳 高凤丽 《吉林水利》 2006年第11期4-6,共3页
Fisher最优分割法是对有序样本进行最优化分段的一种数学方法。本文利用该方法对星星哨水库汛期进行相应的划分,结果表明该方法是可行的。因此,可利用该结果对分期实施不同的汛限水位,使水库的防洪和兴利效益达到最大。
关键词 fisher最优剖法 星星哨水库 汛期期划
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基于信息几何构建朴素贝叶斯分类器 被引量:1
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作者 黄友平 史忠植 《通讯和计算机(中英文版)》 2005年第2期1-6,共6页
朴素贝叶斯分类器是机器学习中一种简单而又有效的分期方法。但是由于它的属性条件独立性假设在实际应用中经常不成立,这影响了它的分类性能。本文基于信息几何和Fisher分,提出了一种新的创建属性集的方法。把原有属性经过Fisher分映... 朴素贝叶斯分类器是机器学习中一种简单而又有效的分期方法。但是由于它的属性条件独立性假设在实际应用中经常不成立,这影响了它的分类性能。本文基于信息几何和Fisher分,提出了一种新的创建属性集的方法。把原有属性经过Fisher分映射成新的属性集,并在新属性集上构建贝叶斯分类器。我们在理论上探讨了新属性间的条件依赖关系,证明了在一定条件下新属性间是条件独立的。试验结果表明,该方法较好地提高了朴素贝叶斯分类器的性能。 展开更多
关键词 朴素贝叶斯类器 信息几何 fisher分 条件独立
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基于Fisher-FCBF的入侵特征选择算法的研究 被引量:2
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作者 王浩 石研 《现代计算机》 2017年第10期7-12,共6页
大量的冗余和噪音数据混合于网络入侵数据中,从而影响到检测的性能和响应。因此,提出基于Fisher-FCBF算法。通过对特征的Fisher分值排序,再使用FCBF算法去冗余,结合SVM,建立分类特征模型,在不降低准确率的前提下,选出最优特征子集,结果... 大量的冗余和噪音数据混合于网络入侵数据中,从而影响到检测的性能和响应。因此,提出基于Fisher-FCBF算法。通过对特征的Fisher分值排序,再使用FCBF算法去冗余,结合SVM,建立分类特征模型,在不降低准确率的前提下,选出最优特征子集,结果表明所提出的方法能够在保证分类准确率的情况下,降低至少11%-21%的计算时间。 展开更多
关键词 入侵检测 特征选择 fisher分 FCBF
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Predicting pillar stability for underground mine using Fisher discriminant analysis and SVM methods 被引量:16
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作者 周健 李夕兵 +2 位作者 史秀志 魏威 吴帮标 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2734-2743,共10页
The purpose of this study is to apply some statistical and soft computing methods such as Fisher discriminant analysis (FDA) and support vector machines (SVMs) methodology to the determination of pillar stability ... The purpose of this study is to apply some statistical and soft computing methods such as Fisher discriminant analysis (FDA) and support vector machines (SVMs) methodology to the determination of pillar stability for underground mines selected from various coal and stone mines by using some index and mechanical properties, including the width, the height, the ratio of the pillar width to its height, the uniaxial compressive strength of the rock and pillar stress. The study includes four main stages: sampling, testing, modeling and assessment of the model performances. During the modeling stage, two pillar stability prediction models were investigated with FDA and SVMs methodology based on the statistical learning theory. After using 40 sets of measured data in various mines in the world for training and testing, the model was applied to other 6 data for validating the trained proposed models. The prediction results of SVMs were compared with those of FDA as well as the measured field values. The general performance of models developed in this study is close; however, the SVMs exhibit the best performance considering the performance index with the correct classification rate Prs by re-substitution method and Pcv by cross validation method. The results show that the SVMs approach has the potential to be a reliable and practical tool for determination of pillar stability for underground mines. 展开更多
关键词 underground mine pillar stability fisher discriminant analysis (FDA) support vector machines (SVMs) PREDICTION
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Fault Diagnosis in Chemical Process Based on Self-organizing Map Integrated with Fisher Discriminant Analysis 被引量:16
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作者 陈心怡 颜学峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期382-387,共6页
Fault diagnosis and monitoring are very important for complex chemical process. There are numerous methods that have been studied in this field, in which the effective visualization method is still challenging. In ord... Fault diagnosis and monitoring are very important for complex chemical process. There are numerous methods that have been studied in this field, in which the effective visualization method is still challenging. In order to get a better visualization effect, a novel fault diagnosis method which combines self-organizing map (SOM) with Fisher discriminant analysis (FDA) is proposed. FDA can reduce the dimension of the data in terms of maximizing the separability of the classes. After feature extraction by FDA, SOM can distinguish the different states on the output map clearly and it can also be employed to monitor abnormal states. Tennessee Eastman (TE) process is employed to illustrate the fault diagnosis and monitoring performance of the proposed method. The result shows that the SOM integrated with FDA method is efficient and capable for real-time monitoring and fault diagnosis in complex chemical process. 展开更多
关键词 self-organizing maps fisher discriminant analysis fault diagnosis MONITORING Tennessee Eastman process
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Fisher discriminant analysis model and its application for prediction of classification of rockburst in deep-buried long tunnel 被引量:10
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作者 ZHOU Jian SHI Xiu-zhi +2 位作者 DONG Lei HU Hai-yan WANG Huai-yong 《Journal of Coal Science & Engineering(China)》 2010年第2期144-149,共6页
A Fisher discriminant analysis (FDA) model for the prediction of classification of rockburst in deep-buried long tunnel was established based on the Fisher discriminant theory and the actual characteristics of the p... A Fisher discriminant analysis (FDA) model for the prediction of classification of rockburst in deep-buried long tunnel was established based on the Fisher discriminant theory and the actual characteristics of the project. First, the major factors of rockburst, such as the maximum tangential stress of the cavern wall σθ, uniaxial compressive strength σc, uniaxial tensile strength or, and the elastic energy index of rock Wet, were taken into account in the analysis. Three factors, Stress coefficient σθ/σc, rock brittleness coefficient σc/σt, and elastic energy index Wet, were defined as the criterion indices for rockburst prediction in the proposed model. After training and testing of 12 sets of measured data, the discriminant functions of FDA were solved, and the ratio of misdiscrimina- tion is zero. Moreover, the proposed model was used to predict rockbursts of Qinling tunnel along Xi'an-Ankang railway. The results show that three forecast results are identical with the actual situation. Therefore, the prediction accuracy of the FDA model is acceptable. 展开更多
关键词 deep-buried tunnel ROCKBURST CLASSIFICATION fisher discriminant analysis model
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BOOTSTRAP TECHNIQUE FOR ROC ANALYSIS: A STABLE EVALUATION OF FISHER CLASSIFIER PERFORMANCE
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作者 Xie Jigang Qiu Zhengding 《Journal of Electronics(China)》 2007年第4期523-527,共5页
This paper presents a novel bootstrap based method for Receiver Operating Characteristic (ROC) analysis of Fisher classifier. By defining Fisher classifier’s output as a statistic, the bootstrap technique is used to ... This paper presents a novel bootstrap based method for Receiver Operating Characteristic (ROC) analysis of Fisher classifier. By defining Fisher classifier’s output as a statistic, the bootstrap technique is used to obtain the sampling distributions of the outputs for the positive class and the negative class respectively. As a result, the ROC curve is a plot of all the (False Positive Rate (FPR), True Positive Rate (TPR)) pairs by varying the decision threshold over the whole range of the boot- strap sampling distributions. The advantage of this method is, the bootstrap based ROC curves are much stable than those of the holdout or cross-validation, indicating a more stable ROC analysis of Fisher classifier. Experiments on five data sets publicly available demonstrate the effectiveness of the proposed method. 展开更多
关键词 Binary classification BOOTSTRAP FDA fisher Discriminant Analysis) ROC (Receiver Operating Characteristic) curve
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On-line Batch Process Monitoring and Diagnosing Based on Fisher Discriminant Analysis
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作者 赵旭 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第3期307-312,316,共7页
A new on-line batch process monitoring and diagnosing approach based on Fisher discriminant analysis (FDA) was proposed. This method does not need to predict the future observations of variables, so it is more sensi... A new on-line batch process monitoring and diagnosing approach based on Fisher discriminant analysis (FDA) was proposed. This method does not need to predict the future observations of variables, so it is more sensitive to fault detection and stronger implement for monitoring. In order to improve the monitoring performance, the variables trajectories of batch process are separated into several blocks. The key to the proposed approach for on-line monitoring is to calculate the distance of block data that project to low-dimension Fisher space between new batch and reference batch. Comparing the distance with the predefine threshold, it can be considered whether the batch process is normal or abnormal. Fault diagnosis is performed based on the weights in fault direction calculated by FDA. The proposed method was applied to the simulation model of fed-batch penicillin fermentation and the resuits were compared with those obtained using MPCA. The simulation results clearly show that the on-line monitoring method based on FDA is more efficient than the MPCA. 展开更多
关键词 batch process on-line process monitoring fault diagnosis fisher discriminant analysis (FDA) multiway principal component analysis (MPCA)
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Exact Solutions of Generalized Burgers-Fisher Equation with Variable Coefficients 被引量:1
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作者 陈博奎 闵松强 汪秉宏 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第3期443-449,共7页
The generalized Riccati equation vational expansion method is extended in this paper. Several exact solutions for the generalized Burgers-Fisher equation with variable coefficients are obtained by this method, and som... The generalized Riccati equation vational expansion method is extended in this paper. Several exact solutions for the generalized Burgers-Fisher equation with variable coefficients are obtained by this method, and some of which are derived for the first time. It is concluded from the results that this approach is simple and efficient even in solving partial differential equations with variable coefficients. 展开更多
关键词 generalized Riccati equation rational expansion method generalized variable coefficient Burgers-fisher equation exact solution
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入侵检测中基于SVM的两级特征选择方法 被引量:35
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作者 武小年 彭小金 +1 位作者 杨宇洋 方堃 《通信学报》 EI CSCD 北大核心 2015年第4期19-26,共8页
针对入侵检测中的特征优化选择问题,提出基于支持向量机的两级特征选择方法。该方法将基于检测率与误报率比值的特征评测值作为特征筛选的评价指标,先采用过滤模式中的Fisher分和信息增益分别过滤噪声和无关特征,降低特征维数;再基于筛... 针对入侵检测中的特征优化选择问题,提出基于支持向量机的两级特征选择方法。该方法将基于检测率与误报率比值的特征评测值作为特征筛选的评价指标,先采用过滤模式中的Fisher分和信息增益分别过滤噪声和无关特征,降低特征维数;再基于筛选出来的交叉特征子集,采用封装模式中的序列后向搜索算法,结合支持向量机选取最优特征子集。仿真测试结果表明,采用该方法筛选出来的特征子集具有更好的分类性能,并有效降低了系统的建模时间和测试时间。 展开更多
关键词 入侵检测 特征选择 支持向量机 fisher分 序列后向搜索
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一种网络入侵检测特征提取方法 被引量:28
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作者 张雪芹 顾春华 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第1期81-86,共6页
为了去除冗余特征,降低系统存储和运算负担,提高网络入侵检测分类器的性能,文中提出了一种基于Fisher分和支持向量机的网络入侵检测特征提取方法.针对KDD′99网络入侵检测数据集,应用该方法得到了混合攻击和4种单一攻击模式下的特征重... 为了去除冗余特征,降低系统存储和运算负担,提高网络入侵检测分类器的性能,文中提出了一种基于Fisher分和支持向量机的网络入侵检测特征提取方法.针对KDD′99网络入侵检测数据集,应用该方法得到了混合攻击和4种单一攻击模式下的特征重要度排序,选取重要特征建立支持向量机入侵检测分类器.结果表明,该分类器精度与使用全部特征构建的支持向量机分类器相当,训练和测试时间则显著降低. 展开更多
关键词 入侵检测系统 特征选取 fisher分 支持向量机
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一种基于用户行为特征选择的点击欺诈检测方法 被引量:5
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作者 董亚楠 刘学军 李斌 《计算机科学》 CSCD 北大核心 2016年第10期145-149,共5页
在线广告是目前众多网络巨头收入的主要来源,在线广告也为网络的健康发展提供了强大的经济支撑。目前,利用用户行为属性特征来识别点击欺诈的方法中,含有较多的冗余特征,检测效率相对较低。针对这一问题,提出了一种属性特征选择与分类... 在线广告是目前众多网络巨头收入的主要来源,在线广告也为网络的健康发展提供了强大的经济支撑。目前,利用用户行为属性特征来识别点击欺诈的方法中,含有较多的冗余特征,检测效率相对较低。针对这一问题,提出了一种属性特征选择与分类方法相结合的欺诈检测方法。通过训练数据集找到欺诈用户点击广告的属性特征集合,采用Fisher分方法得到了属性特征重要度排序,选取重要属性特征,并基于这些重要的特征使用支持向量机二分类方法分类。在真实数据集上的实验结果证明了该方法的可行性与有效性。 展开更多
关键词 点击欺诈 fisher分 支持向量机 特征选择
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基于特征选择的两级混合入侵检测方法 被引量:4
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作者 江泽涛 周谭盛子 +1 位作者 胡硕 时晨 《计算机工程与设计》 北大核心 2020年第3期614-620,共7页
为提高入侵检测方法的检测率、降低误报率并提高对未知类型攻击准确率,提出一种以特征选择为基础的混合入侵检测方法。利用fisher分对特征进行降维处理,选择出与类别相关度大的特征子集;为解决样本的多元性问题,引入超图的Helly属性对... 为提高入侵检测方法的检测率、降低误报率并提高对未知类型攻击准确率,提出一种以特征选择为基础的混合入侵检测方法。利用fisher分对特征进行降维处理,选择出与类别相关度大的特征子集;为解决样本的多元性问题,引入超图的Helly属性对得到的特征子集进行再次筛选,得到最终的最优特征子集;利用随机森林和改进的K均值(K-Means)聚类作为联合分类器,采用二次检测的方式确定样本所属类别。实验结果表明,该方法有效且可行,为入侵检测提供了可参考的算法模型。 展开更多
关键词 入侵检测 特征选择 fisher分 降维处理 超图 随机森林 K均值
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A Novel Systematic Method of Quality Monitoring and Prediction Based on FDA and Kernel Regression 被引量:2
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作者 张曦 马思乐 +2 位作者 阎威武 赵旭 邵惠鹤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期427-436,共10页
A novel systematic quality monitoring and prediction method based on Fisher discriminant analysis (FDA) and kernel regression is proposed. The FDA method is first used for quality monitoring. If the process is un-der ... A novel systematic quality monitoring and prediction method based on Fisher discriminant analysis (FDA) and kernel regression is proposed. The FDA method is first used for quality monitoring. If the process is un-der normal condition, then kernel regression is further used for quality prediction and estimation. If faults have oc-curred, the contribution plot in the fault feature direction is used for fault diagnosis. The proposed method can ef-fectively detect the fault and has better ability to predict the response variables than principle component regression (PCR) and partial least squares (PLS). Application results to the industrial fluid catalytic cracking unit (FCCU) show the effectiveness of the proposed method. 展开更多
关键词 quality monitori-ng -quality prediction fisher discriminant analysis kernel regression fluid catalyticcracking unit
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Predictors of the outcomes of acute-on-chronic hepatitis B liver failure 被引量:17
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作者 Hsiu-Lung Fan Po-Sheng Yang +6 位作者 Hui-Wei Chen Teng-Wei Chen De-Chuan Chan Chi-Hong Chu Jyh-Cherng Yu Shih-Ming Kuo Chung-Bao Hsieh 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第36期5078-5083,共6页
AIM: To identify the risk factors in predicting the out- come of acute-on-chronic hepatitis B liver failure pa- tients. METHODS: We retrospectively divided 113 patients with acute-on-chronic liver failure-hepatitis ... AIM: To identify the risk factors in predicting the out- come of acute-on-chronic hepatitis B liver failure pa- tients. METHODS: We retrospectively divided 113 patients with acute-on-chronic liver failure-hepatitis B virus (ACLF-HBV) and without concurrent hepatitis C or D virus infection and hepatocellular carcinoma into two groups according to their outcomes after anti-HBV therapy. Their demographic, clinical, and biochemical data on the day of diagnosis and after the first week of treatment were analyzed using the Mann-Whitney U test, Fisher's exact test, and a multiple logistic regres- sion analysis. RESULTS: The study included 113 patients (87 men and 26 women) with a mean age of 49.84 years. Fifty- two patients survived, and 61 patients died. Liver failure (85.2%), sepsis (34.4%), and multiple organ failure (39.3%) were the main causes of death. Mul- tivariate analyses showed that Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ scores ≥ 12 [odds ratio (OR) = 7.160, 95% CI: 2.834-18.092, P 〈 0.001] and positive blood culture (OR = 13.520, 95% CI: 2.740-66.721, P = 0.001) on the day of diagnosis and model for end-stage liver disease (MELD) scores 28 (OR = 8.182, 95% CI: 1.884-35.527, P = 0.005) after the first week of treatment were independent predictors of mortality. CONCLUSION: APACHE II scores on the day of diag- nosis and MELD scores after the first week of anti-HBV therapy are feasible predictors of outcome in ACLF- HBV patients. 展开更多
关键词 LAMIVUDINE Liver failure Hepatitis B virus Acute Physiology and Chronic Health Evaluation ]]score Model for end-stage liver disease scores
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A novel multimode process monitoring method integrating LCGMM with modified LFDA 被引量:4
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作者 任世锦 宋执环 +1 位作者 杨茂云 任建国 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1970-1980,共11页
Complex processes often work with multiple operation regions, it is critical to develop effective monitoring approaches to ensure the safety of chemical processes. In this work, a discriminant local consistency Gaussi... Complex processes often work with multiple operation regions, it is critical to develop effective monitoring approaches to ensure the safety of chemical processes. In this work, a discriminant local consistency Gaussian mixture model(DLCGMM) for multimode process monitoring is proposed for multimode process monitoring by integrating LCGMM with modified local Fisher discriminant analysis(MLFDA). Different from Fisher discriminant analysis(FDA) that aims to discover the global optimal discriminant directions, MLFDA is capable of uncovering multimodality and local structure of the data by exploiting the posterior probabilities of observations within clusters calculated from the results of LCGMM. This may enable MLFDA to capture more meaningful discriminant information hidden in the high-dimensional multimode observations comparing to FDA. Contrary to most existing multimode process monitoring approaches, DLCGMM performs LCGMM and MFLDA iteratively, and the optimal subspaces with multi-Gaussianity and the optimal discriminant projection vectors are simultaneously achieved in the framework of supervised and unsupervised learning. Furthermore, monitoring statistics are established on each cluster that represents a specific operation condition and two global Bayesian inference-based fault monitoring indexes are established by combining with all the monitoring results of all clusters. The efficiency and effectiveness of the proposed method are evaluated through UCI datasets, a simulated multimode model and the Tennessee Eastman benchmark process. 展开更多
关键词 Multimode process monitoring Discriminant local consistency Gaussian mixture model Modified local fisher discriminant analysis Global fault detection index Tennessee Eastman process
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Effect of Heteroscedastic Variance Covariance Matrices on Two Groups Linear Classification Techniques
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《Journal of Mathematics and System Science》 2014年第2期133-138,共6页
The authors investigate the comparative classification performance of the two groups linear classification techniques. They compared the Fisher linear classification analysis, its robust version based on the minimum c... The authors investigate the comparative classification performance of the two groups linear classification techniques. They compared the Fisher linear classification analysis, its robust version based on the minimum covariance determinant with the Filter linear classification rule and the linear combination linear classification technique. These procedures are investigated using laboratory reared aedes albopictus mosquito data set and simulated data set generated based on heteroscedastic covariance matrices with various proportion of contamination. The evaluation procedure is based on the effect of contamination on the mean probabilities of correct classification obtain for each technique. The comparative analysis revealed that the robust Fisher linear classification rule and the linear combination linear classification rule are robust and comparable than the other procedures. 展开更多
关键词 CLASSIFICATION Heteroscedastic mean probability robust.
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XAF1 is frequently methylated in human esophageal cancer 被引量:10
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作者 Xiang-Yu Chen Qiao-Yu He Ming-Zhou Guo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第22期2844-2849,共6页
AIM: To explore epigenetic changes in the gene encod- ing X chromosome-linked inhibitor of apoptosis-associ- ated factor 1 (XAF1) during esophageal carcinogenesis. METHODS: Methylation status of XAF1 was detected ... AIM: To explore epigenetic changes in the gene encod- ing X chromosome-linked inhibitor of apoptosis-associ- ated factor 1 (XAF1) during esophageal carcinogenesis. METHODS: Methylation status of XAF1 was detected by methylation-specific polymerase chain reaction (MSP) in four esophageal cancer cell lines (KYSE30, KYSE70, BICl and partially methylated in TE3 cell lines), nine cases of normal mucosa, 72 cases of pri- mary esophageal cancer and matched adjacent tissue. XAF1 expression was examined by semi-quantitative reverse transcriptional polymerase chain reaction and Western blotting before and after treatment with 5-aza- deoxycytidine (5-aza-dc), a demethylating agent. To investigate the correlation of XAF1 expression and methylation status in primary esophageal cancer, immu- nohistochemistry for XAF1 expression was performed in 32 cases of esophageal cancer and matched adjacent tissue. The association of methylation status and clini-copathological data was analyzed by logistic regression. RESULTS: MSP results were as follows: loss of XAF1 expression was found in three of four esophageal cell lines with promoter region hypermethylation (com- pletely methylated in KYSE30, KYSE70 and BIC1 cell lines and partially in TE3 cells); all nine cases of normal esophageal mucosa were unmethylated; and 54/72 (75.00%) samples from patients with esophageal can- cer were methylated, and 25/72 (34.70%) matched adjacent tissues were methylated (75.00% vs 34,70%, z2 = 23.5840, P = 0.000). mRNA level of XAF1 mea- sured with semi-quantitative reverse transcription poly- merase chain reaction was detectable only in TE3 cells, and no expression was detected in KYSE30, KYSE70 or BIC1 cells. Protein expression was not observed in KYSE30 cells by Western blotting before treatment with 5-aza-dc. After treatment, mRNA level of XAF1 was detectable in KYSE30, KYSE70 and BIC1 cells. Protein expression was detected in KYSE30 after treatment with 5-aza-dc. Immunohistochemistry was performed on 32 cases of esophageal cancer and adjacent tissue, and demonstrated XAF1 in the nucleus and cytoplasm. XAF1 staining was found in 20/32 samples of adjacent normal tissue but was present in only 8/32 samples of esophageal cancer tissue (Z2= 9.143, P = 0.002). XAF1 expression was decreased in cancer samples compared with adjacent tissues. In 32 cases of esophageal can- cer, 24/32 samples were methylated, and 8/32 esopha- geal cancer tissues were unmethylated. XAF1 staining was found in 6/8 samples of unmethylated esophageal cancer and 2/24 samples of methylated esophageal cancer tissue. XAF1 staining was inversely correlated with XAF1 promoter region methylation (Fisher's exact test, P = 0.004). Regarding methylation status and clinicopathological data, no significant differences were found in sex, age, tumor size, tumor stage, or metas- tasis with respect to methylation of XAF1 for the 72 tis- sue samples from patients with esophageal cancer. CONCLUSION: XAF1 is frequently methylated in eso- phageal cancer, and XAF1 expression is regulated by promoter region hypermethylation. 展开更多
关键词 X chromosome-linked inhibitor of apoptosis-associated factor 1 Esophageal cancer METHYLATION Methylation-specific polymerase chain reaction Semi-quantitative reverse transcriptional polymerase chainreaction
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Argentinean Commercial Malbec Wines: Regional Sensory Profiles
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作者 Ana Carla Aruani Claudia Ines Quini +3 位作者 Hugo Ortiz Rodoifo Videla Marcelo Murgo Sebastian Prieto 《Journal of Life Sciences》 2014年第2期134-141,共8页
Sensory evaluation was performed on 32 commercial Malbec wines (2008 and 2009 vintages) produced in five provinces of Argentina. Wines from different areas in Mendoza (the most important producer of Malbec) were a... Sensory evaluation was performed on 32 commercial Malbec wines (2008 and 2009 vintages) produced in five provinces of Argentina. Wines from different areas in Mendoza (the most important producer of Malbec) were also included to test possible differences within this province. Ten key attributes were first recognized by descriptive analyses and then carefully evaluated by a trained sensory panel composed of 10 judges. Among the aroma and flavour attributes the analyses focused on plum, red fruits, white pepper, bell pepper, and floral. Three attributes of taste (acidity, astringency, and bitterness) and two attributes of color (red and blue-purple hues) were also analyzed. Statistical differences and similarities in sensory data were tested using analysis of variance (ANOVA), multiple means comparisons by least significant difference test (Fisher LSD), and principal component analysis (PCA). ANOVA and Fisher LSD tests of sensory data showed significant differences (P 〈 0.05) for 6 out of 10 wine attributes: plum, floral, red fruits, astringency, red and blue- purple hues. 展开更多
关键词 Malbec red wines commercial wines sensory analysis ARGENTINA Mendoza.
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