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International Journal of Biomathematics 2018年第8期11卷 71-85页

作者： Mohamed M. Khader Khaled M. Saad Department of Mathematics and Statistics College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU) Riyadh Saudi Arabia Department of Mathematics Faculty of Science Benha University Benha Egypt Department of Mathematics College of Arts and Sciences Najran University Najran Saudi Arabia Department of Mathematics Faculty of Applied Science Taiz University Taiz Yemen

In this paper, an efficient numerical method is introduced for solving the fractional (Caputo sense) Fisher equation. We use the spectral collocation method which is based upon Chebyshev approximations. The properties of Chebyshev polynomials of the third kind are used to reduce the proposed problem to a system of ODEs, which is solved by the finite difference method (FDM). Some theorems about the convergence analysis are stated and proved. A numerical simulation is given and the results are compared with the exact solution.

关键词： Fractional Fisher equation FDM Chebyshev polynomials convergence analysis

基于Fisher-SVM特征选择的负荷辨识研究

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电力科学与技术学报 2023年第4期38卷 230-239,264页

作者：栾开宁杨世海黄艺璇方凯杰程含渺黄时国网江苏省电力有限公司江苏南京210028 江苏智臻能源科技有限公司江苏南京211111

针对当前非侵入式负荷辨识中不同设备特征选择上主观性、盲目性的问题,提出基于Fisher-SVM特征选择的非侵入式负荷辨识算法。首先,基于高频采样终端提取入户侧电流、电压原始数据,使用傅里叶变换对原始信号分解得有功、无功及谐波时间序... 详细信息

针对当前非侵入式负荷辨识中不同设备特征选择上主观性、盲目性的问题,提出基于Fisher-SVM特征选择的非侵入式负荷辨识算法。首先,基于高频采样终端提取入户侧电流、电压原始数据,使用傅里叶变换对原始信号分解得有功、无功及谐波时间序列;其次,将负荷波形分为4个阶段并计算得到负荷波形暂稳态特征;然后,通过Fisher-SVM算法在不同分类器中对特征进行选择,得到最优分类特征子集,并利用Sigmoid函数对结果进行概率校准;最后,根据贝叶斯理论对各分类器进行融合从而实现对不同负荷的辨识。以3类台区831户实际用户进行算法测试。结果表明,该算法能够有效利用不同电器负荷印记的独特性,克服特征选择上的盲目性,提高负荷辨识能力。

关键词：非侵入式负荷辨识 Fisher 支持向量机特征提取

Assessment of micronucleus frequency in exfoliated buccal epithelial cells among Fisher folks exposed to mine tailings in Marinduque Island,Philippines

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Asian Pacific Journal of Tropical Medicine 2010年第4期3卷 315-317页

作者： Elena M Ragragio Celeste P Belleza Mark C Narciso Glenn L Sia Su Biology Department University of the Philippines-ManilaManilaPhilippines Biology Department De La Salle UniversityManilaPhilippines

Objective:To evaluate the potential toxic effects of mine tailings exposure among the Fisher folks residing near and far from the Calancan Bay,Marinduque,using the micronucleus assay as an endpoint.Methods:The Fisher folks residing near and far from the Calancan Bay were interviewed and the presence and frequency of cells with micronucleus in exfoliated buccal epithelial cells were examined.Results:Results showed that the prevalence of cells with micronucleus was higher among the Fisher folks who were directly exposed to the mine tailings as compared with those Fisher folks who reside in a community without exposure of mine tailings and history of mining(P<0.05).Conclusions:The presence and the significant difference in the cells with micronuclei observed near the Calancan Bay could possibly indicate a prolonged chemical stress caused by the toxic heavy metals in the mine tailings and the environment.

关键词： Micronuleus frequency Epithelial cells Fisher folks

Wave Fronts of a Generalized Fisher Equation

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Chinese Science Bulletin 1994年第16期39卷 1326-1328页

作者：王明新 Institute of Applied Mathematics Academia Sinica Beijing 100080 PRC Department of Mathematics Henan University Kaifeng 475001 PRC

We study the wave fronts, connecting 0 to 1, of the generalized Fisher equation ut=uxx+unf（u）,（1） where n>0; f（?）C [0, 1] satisfies the following conditions （A）, （C） or （B）, （C）. （A） f（u）=|u-a|lG（u... 详细信息

关键词： Fisher equation wave front.

Silhouettes Based Human Action Recognition in Video via Procrustes Analysis and Fisher Vector Coding

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Journal of Donghua University(English Edition) 2019年第2期36卷 140-148页

作者：蔡加欣钟然旭李俊杰 School of Applied Mathematics Xiamen University of TechnologyXiamen 361024China Department of Software Research and Development Guangdong Grandmark Automotive Systems Co.Ltd.Dongguan 523000China

This paper proposes a framework for human action recognition based on procrustes analysis and Fisher vector coding(FVC).Firstly,we applied a pose feature extracted from silhouette image by employing Procrustes analysis and local preserving projection(LPP).Secondly,the extracted feature can preserve the discriminative shape information and local manifold structure of human pose and is invariant to translation,rotation and scaling.Finally,after the pose feature was extracted,a recognition framework based on FVC and multi-class supporting vector machine was employed to classify the human action.Experimental results on benchmarks demonstrate the effectiveness of the proposed method.

关键词： human action recognition Procrustes analysis local preserving projection Fisher vector coding(FVC)

EXACT SOLITARY WAVE SOLUTIONS OF THE GENERALIZED Fisher EQUATION

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Chinese Science Bulletin 1989年第2期34卷 106-109页

作者：王心宜 Department of Physics Suzhou University Institute of Theoretical Physics Academia Sinica Beijing Institute of Solid State Nanjing University

Aroson and Weinberger systematically investigated the following nonlinear problem in 1975—1978:

关键词： Fisher equation exact solution solitary wave.

荧光光谱成像技术结合主成分分析与Fisher判别快速鉴别肉苁蓉

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光谱学与光谱分析 2015年第3期35卷 689-694页

作者：黎远鹏黄富荣董佳肖迟冼瑞仪马志国赵静暨南大学光电工程系广东广州510632 暨南大学药学院广东广州510632 华南农业大学理学院广东广州510636

为探究一种快速、可靠的肉苁蓉属中药材检测方法，实验采用荧光光谱成像技术结合模式识别方法对肉苁蓉属三种中药材：荒漠肉苁蓉、管花肉苁蓉和沙苁蓉进行鉴别研究。实验中发现肉苁蓉样品存在较显著的荧光特性，采集来自不同产地、不同... 详细信息

为探究一种快速、可靠的肉苁蓉属中药材检测方法，实验采用荧光光谱成像技术结合模式识别方法对肉苁蓉属三种中药材：荒漠肉苁蓉、管花肉苁蓉和沙苁蓉进行鉴别研究。实验中发现肉苁蓉样品存在较显著的荧光特性，采集来自不同产地、不同批次以及不同超市购买的三种肉苁蓉属药材的40个样品的荧光光谱图像，对图像进行去噪、二值化处理后，根据光谱立方体绘制每个样本的光谱曲线，将所得450～680 nm 波段范围内的光谱数据作为鉴别分析的研究对象，应用主成分分析法（PCA）对三种肉苁蓉的光谱数据进行降维处理，再结合 Fisher 判别方法对三种肉苁蓉进行鉴别。分别比较多元散射校正（MSC）、标准正态变量校正变换（SNV）以及一阶微分（FD）三种数据预处理方法对鉴别模型的影响，并根据主成分的累积贡献率和主成分因子数对判别模型效果的影响对主成分因子数进行优化。分析结果表明：一阶微分预处理后提取前四个主成分进行 Fisher 判别的鉴别效果最佳，PCA 结合 Fisher 判别建立肉苁蓉属三种药材的判别模型原始判别的准确率达到100％，交叉验证的准确率达到95％。由此可见，利用荧光光谱成像技术结合主成分分析及 Fisher 判别对肉苁蓉属三种药材的鉴别分析是可行的，而且具有操作简便、快速、可靠等优点。

关键词：荧光光谱成像主成分分析 Fisher 判别肉苁蓉鉴别

Fisher&Paykel AIRVO_(2)高流量氧疗与无创通气在肺癌合并呼吸衰竭患者中的应用

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中国医疗器械信息 2023年第7期29卷 101-103页

作者：白洁天津市泰达医院呼吸科天津300457

目的:对比分析Fisher&Paykel AIRVO_(2)高流量氧疗与无创通气在肺癌合并呼吸衰竭患者中的应用效果。方法:将2019年1月~2021年12月本院收治的肺癌合并呼吸衰竭患者78例作为研究对象,根据电脑随机分组法实现患者分组,其中39例患者为观察组... 详细信息

目的:对比分析Fisher&Paykel AIRVO_(2)高流量氧疗与无创通气在肺癌合并呼吸衰竭患者中的应用效果。方法:将2019年1月~2021年12月本院收治的肺癌合并呼吸衰竭患者78例作为研究对象,根据电脑随机分组法实现患者分组,其中39例患者为观察组,给予Fisher&Paykel AIRVO_(2)高流量氧疗,另外39例患者为对照组,给予无创通气,分析比较两组患者的治疗效果。结果:治疗前两组患者呼吸循环情况、呼吸困难程度、舒适度评分以及肺部感染评分与健康状况评分均无显著差异,P>0.05;观察组患者治疗后上述指标显著差别于对照组患者,PFisher&Paykel AIRVO_(2)高流量氧疗是一种理想的治疗方式,与无创通气相比效果更为显著。

关键词： Fisher & Paykel AIRVO_(2)高流量氧疗无创通气肺癌呼吸衰竭

Sobolev Gradient Approach for Huxley and Fisher Models for Gene Propagation

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Applied Mathematics 2013年第8期4卷 1212-1219页

作者： Nauman Raza Sultan Sial Department of Mathematics Lahore University of Management Sciences Lahore Pakistan Department of Mathematics University of the Punjab Lahore Pakistan Department of Mathematics and Statistics McMaster University Hamilton Canada

The application of Sobolev gradient methods for finding critical points of the Huxley and Fisher models is demonstrated. A comparison is given between the Euclidean, weighted and unweighted Sobolev gradients. Results ... 详细信息

关键词： Sobolev Gradient Huxley and Fisher Models Descent Methods

A Direct Derivation of the Exact Fisher Information Matrix for Bivariate Bessel Distribution of Type I

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Applied Mathematics 2012年第3期3卷 276-282页

作者： Mohammad Reza Kazemi Alireza Nematollahi Department of Statistics College of Sciences Shiraz University Shiraz Iran Department of Statistics Fasa University Fasa Iran

This paper deals with a direct derivation of Fisher’s information matrix for bivariate Bessel distribution of type I. Some tools for the numerical computation and some tabulations of the Fisher’s information matrix ... 详细信息

关键词： Bessel Distribution Fisher Information Matrix Digamma Function