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The Paley-Wiener Theorem for General Weighted Hardy Spaces on Tube Domains
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作者 HUANG Yun ZHANG Dawei 《应用数学》 北大核心 2025年第3期841-849,共9页
In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequen... In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequence of L^(1)functions converging to the given function and verifying their representation in the form of Fourier transform to establish the desired result of the given function.Applying this main result,we further generalize the Paley-Wiener theorem for band-limited functions to the analytic function spaces L^(p)(0<p<∞)with general weights. 展开更多
关键词 Paley-Wiener Theorem Fourier transform weighted Hardy space Tube domain
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Products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball
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作者 ZHANG Chao QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第2期160-169,共10页
The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic fu... The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results. 展开更多
关键词 composition operator multiplication operator differentiation operator weighted Bergman space
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Equivalent Conditions of Complete Convergence for Weighted Sums of Sequences of i.i.d.Random Variables under Sublinear Expectations
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作者 XU Mingzhou CHENG Kun 《应用概率统计》 北大核心 2025年第3期339-352,共14页
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the... The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space. 展开更多
关键词 complete convergence weighted sums i.i.d.random variables sublinear expectation
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Complete Convergenceand Complete Moment Convergence for Weighted Sums of ANA Random Variables 被引量:1
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作者 MENG Bing WU Qunying 《应用概率统计》 CSCD 北大核心 2024年第5期710-724,共15页
In this paper,we investigate the complete convergence and complete moment conver-gence for weighted sums of arrays of rowwise asymptotically negatively associated(ANA)random variables,without assuming identical distri... In this paper,we investigate the complete convergence and complete moment conver-gence for weighted sums of arrays of rowwise asymptotically negatively associated(ANA)random variables,without assuming identical distribution.The obtained results not only extend those of An and Yuan[1]and Shen et al.[2]to the case of ANA random variables,but also partially improve them. 展开更多
关键词 ANA random variables complete convergence complete moment convergence weighted sums
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The molecular weight of carbon dots calculated from colligative properties and their application in estimating surface adsorption capacity
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作者 Ting Sun Xinzhi Liang +3 位作者 Minghao Pang Xia Xin Ning Feng Hongguang Li 《日用化学工业(中英文)》 北大核心 2025年第4期422-429,共8页
Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to... Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to CDs are atomically imprecise and their molecular weight distribution is broad.In this paper,a series of Pluronic-modified CDs were prepared and the structure of the CDs was briefly analyzed.Subsequently,a molecular weight measurement method based on colligative properties was developed,and the correction coefficient in the algorithm was briefly analyzed.The calculated molecular weight was applied to the determination of surface adsorption capacity.This work provided a method for averaging the molecular weight of atomically imprecise particulate materials,which is expected to provide new opportunities in related fields. 展开更多
关键词 carbon dots molecular weight colligative properties surface adsorption capacity
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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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Infrared small target detection algorithm via partial sum of the tensor nuclear norm and direction residual weighting
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作者 SUN Bin XIA Xing-Ling +1 位作者 FU Rong-Guo SHI Liang 《红外与毫米波学报》 北大核心 2025年第2期277-288,共12页
Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small targe... Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target. 展开更多
关键词 infrared small target detection infrared patch tensor model partial sum of the tensor nuclear norm direction residual weighting
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Optimization of Infrared-microwave Post-processing Process for 3D Printed Raspberry Preserves Based on AHP-CRITIC Hybrid Weighting Combined with Response Surface Method
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作者 Zheng Xianzhe Song Ruonan +2 位作者 Cong Hongyue Zhang Yuhan Xue Liangliang 《Journal of Northeast Agricultural University(English Edition)》 2025年第1期27-44,共18页
In order to improve the quality of 3D printed raspberry preserves after post-processing,microwave ovens combining infrared and microwave methods were utilized.The effects of infrared heating temperature,infrared heati... In order to improve the quality of 3D printed raspberry preserves after post-processing,microwave ovens combining infrared and microwave methods were utilized.The effects of infrared heating temperature,infrared heating time,microwave power,microwave heating time on the center temperature,moisture content,the chroma(C*),the total color difference(ΔE*),shape fidelity,hardness,and the total anthocyanin content of 3D printed raspberry preserves were analyzed by response surface method(RSM).The results showed that under combining with the two methods,infrared heating improved the fidelity and quality degradation of printed products,while microwave heating enhanced the efficiency of infrared heating.Infrared-microwave combination cooking could maintain relatively stable color appearance and shape of 3D printed raspberry preserves.The AHP–CRITIC hybrid weighting method combined with the response surface test to determine the comprehensive weights of the evaluation indicators optimized the process parameters,and the optimal process parameters were obtained:infrared heating temperature of 190℃,infrared heating time of 10 min and 30 s,microwave power of 300 W,and microwave heating time of 2 min and 6 s.The 3D printed raspberry cooking methods obtained under the optimal conditions seldom had color variation,porous structure,uniform texture,and high shape fidelity,which retained the characteristics of personalized manufacturing by 3D printing.This study could provide a reference for the postprocessing and quality control of 3D cooking methods. 展开更多
关键词 3D printing RASPBERRY MICROWAVE infrared heating hybrid weighting response surface method
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Design and optimization of the RGB beam combiner in micro display using entropy weight-TOPSIS method
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作者 ZHENG Yu ZHAO Yan-bing +4 位作者 ZOU Xin-jie WANG Ji-rong JIANG Xiang LIU Jian-zhe DUAN Ji-an 《Journal of Central South University》 2025年第2期483-494,共12页
Red-green-blue(RGB)beam combiners are widely used in scenarios such as augmented reality/virtual reality(AR/VR),laser projection,biochemical detection,and other fields.Optical waveguide combiners have attracted extens... Red-green-blue(RGB)beam combiners are widely used in scenarios such as augmented reality/virtual reality(AR/VR),laser projection,biochemical detection,and other fields.Optical waveguide combiners have attracted extensive attention due to their advantages of small size,high multiplexing efficiency,convenient mass production,and low cost.An RGB beam combiner based on directional couplers is designed,with a core-cladding relative refractive index difference of 0.75%.The RGB beam combiner is optimized from the perspective of parameter optimization.Using the beam propagation method(BPM),the relationship between the performance of the RGB beam combiner and individual parameters is studied,achieving preliminary optimization of the device’s performance.The key parameters of the RGB beam combiner are optimized using the entropy weight-technique for order preference by similarity to an ideal solution TOPSIS method,establishing the optimal parameter scheme and further improving the device’s performance indicators.The results show that after optimization,the multiplexing efficiencies for red,green,and blue lights,as well as the average multiplexing efficiency,reached 99.17%,99.76%,96.63%and 98.52%,respectively.The size of the RGB beam combiner is 4.768 mm×0.062 mm. 展开更多
关键词 optical waveguide combiners red-green-blue beam combiner beam propagation method entropy weight TOPSIS method multiplexing efficiency
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GIS支持的Eigenface法——适于只有一个模型单元时的矿产定量预测方法 被引量:6
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作者 张振飞 高凤亮 +1 位作者 马智民 姜常义 《地质与勘探》 CAS CSCD 北大核心 2001年第6期51-54,共4页
在研究和开发程度较低地区开展矿产预测 ,往往只能有很少矿产地用以建立定量预测模型 ,此时大多数统计分析方法不适用。一种GIS支持的基于“单元簇”概念的多源地学信息综合分析方法即Eigenface法 ,比较适合于只有一个模型单元时的建模... 在研究和开发程度较低地区开展矿产预测 ,往往只能有很少矿产地用以建立定量预测模型 ,此时大多数统计分析方法不适用。一种GIS支持的基于“单元簇”概念的多源地学信息综合分析方法即Eigenface法 ,比较适合于只有一个模型单元时的建模。单元簇是相邻若干网格单元的空间定量组合Eigenface法先求出这种高维组合变量空间的某个低维特征子空间 ,然后计算未知单元簇和已知单元簇在特征子空间上投影点的距离来评价未知单元的找矿有利性。Eigenface法与GIS集成是将单元作为区图元 ,利用GIS空间 -属性分析功能提取预测信息并对单元和单元簇进行操作。 展开更多
关键词 矿产预测 eigenface GIS 新疆 地理信息系统 单元簇
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Eigenface的变维分类方法及其在表情识别中的应用 被引量:11
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作者 赵力庄 高文 陈熙霖 《计算机学报》 EI CSCD 北大核心 1999年第6期627-632,共6页
将Eigenface多子空间分类方法用于面部表情识别;针对传统多子空间分类方法中的问题和缺点,提出了两种变维分类方法——静态变维分类和动态变维分类.根据脸部不同区域所含表情成分的不同,将人脸图像划分成表情子区域,构成... 将Eigenface多子空间分类方法用于面部表情识别;针对传统多子空间分类方法中的问题和缺点,提出了两种变维分类方法——静态变维分类和动态变维分类.根据脸部不同区域所含表情成分的不同,将人脸图像划分成表情子区域,构成表情子图像;并分别对各类表情子图像集求解其表情特征子空间.在识别时,用变维分类方法把表情子图像分别投影到各个表情特征子空间上,根据该图像与其在表情特征子空间的投影之间的相似性来进行分类. 展开更多
关键词 eigenface 变维分类 表情识别 人脸识别
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Weighted SVM在蛋白质磷酸化位点预测中的应用 被引量:10
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作者 赵凌志 刘颖 覃征 《计算机工程与应用》 CSCD 北大核心 2006年第3期155-157,167,共4页
Weighted SVM是标准SVM针对非均衡样本的改进。首次将Weighted SVM用于蛋白质磷酸化位点的预测,在最新版的蛋白质磷酸化数据集PhosphoBase上,取得了目前为止最好的分类精度。k-fold交叉验证和独立测试集实验的结果表明,通过对样本数相... Weighted SVM是标准SVM针对非均衡样本的改进。首次将Weighted SVM用于蛋白质磷酸化位点的预测,在最新版的蛋白质磷酸化数据集PhosphoBase上,取得了目前为止最好的分类精度。k-fold交叉验证和独立测试集实验的结果表明,通过对样本数相对较少的正样本赋予较大的惩罚参数,Weighted SVM有效地改善了分类器向负样本方向的“偏斜”,提高了总的预测正确率以及(正样本)查全率。 展开更多
关键词 weighted SVM 蛋白质磷酸化 生物信息学 数据挖掘
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Eigenface算法与EBGM算法的适应性比较 被引量:4
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作者 万峰 杜明辉 《计算机工程与应用》 CSCD 北大核心 2005年第26期69-71,107,共4页
Eigenface算法和EBGM算法是人脸识别的两种重要算法。前者基于图像的整体特征,后者通过Gabor变换提取图像的局部特征。在实际应用中,光照的变化、人物表情的变化和物体对人脸的遮盖等因素造成了人脸识别的困难。文章对上述两种算法在这... Eigenface算法和EBGM算法是人脸识别的两种重要算法。前者基于图像的整体特征,后者通过Gabor变换提取图像的局部特征。在实际应用中,光照的变化、人物表情的变化和物体对人脸的遮盖等因素造成了人脸识别的困难。文章对上述两种算法在这些变化因素下的识别性能进行了研究和比较。实验结果表明EBGM算法对环境变化具有更好的适应性,能够在小样本条件下获得良好的识别能力。而Eigenface算法对环境变化较为敏感,需要大量的训练样本来保证识别效果。 展开更多
关键词 人脸识别 特征脸算法 弹性束图匹配算法 特征提取
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用Weighted fusion方法对森林中蝙蝠活动数据做变量选取
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作者 魏岩峰 唐吉龙 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2013年第1期35-38,共4页
利用Weighted fusion变量选择方法,分析了森林中蝙蝠活动数据.计算了各变量之间的样本相关系数,画出了响应变量与预测变量之间的散点图,对预测变量按照重要性进行了排序,并且根据AIC与BIC准则选出了跟蝙蝠活动显著相关的预测变量.
关键词 变量选择 weighted FUSION 相关系数 AIC
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基于weighted slope one用户聚类的林产品推荐算法 被引量:1
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作者 郑丹 王名扬 陈广胜 《森林工程》 2016年第5期65-70,共6页
随着电商平台用户、林产品数量规模不断扩大,协同过滤推荐时构建的用户-林产品评分矩阵变得高维稀疏,导致推荐算法精度和可扩展度下降。基于此本文提出一种weighted slope one用户聚类推荐算法,将其应用在林业产品个性化推荐服务中。首... 随着电商平台用户、林产品数量规模不断扩大,协同过滤推荐时构建的用户-林产品评分矩阵变得高维稀疏,导致推荐算法精度和可扩展度下降。基于此本文提出一种weighted slope one用户聚类推荐算法,将其应用在林业产品个性化推荐服务中。首先,通过weighted slope one算法的思想填充高维稀疏的用户-林产品评分矩阵;其次,使用Kmeans聚类算法对用户进行聚类,产生相似用户集合,缩小推荐过程中邻居用户的搜索范围;最后,在大数据Mahout平台进行实际推荐,为林产品贸易平台个性化推荐服务的大规模实现奠定基础。经仿真实验表明,文中提出的算法能够全面提升推荐的精度和可扩展性。 展开更多
关键词 林产品推荐 weightedslopeone K-MEANS 协同过滤
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基于AR模型KPCA-Weighted LSSVM的减振性能预测研究
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作者 陈庆堂 黄宜坚 宋一然 《机床与液压》 北大核心 2014年第1期7-11,共5页
以磁流变减振系统为研究对象,建立了基于时间序列自回归模型核主元分析的加权最小二乘支持向量机预测模型,预测系统的减振性能。分析结果表明:这一预测模型降低了模型的复杂程度,具有较高的预测精度,适用于系统性能预测与实时状态监控。
关键词 磁流变减振系统 AR模型 核主元分析 最小二乘支持向量机
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一种改进的CHNN图像边缘检测方法—Weighted CHNN
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作者 赵广复 张有顺 《计算机应用与软件》 CSCD 北大核心 2012年第5期256-259,共4页
针对文献[1]中提出的CHNN图像边缘检测算法缺乏足够的参数来调节边缘检测的灵敏度以及检测结果图像边缘过宽的缺陷,提出一种改进的CHNN方法,称之为Weighted CHNN(加权的CHNN,简称WCHNN)方法。该方法在CHNN神经网络元的n个连接上施加权值... 针对文献[1]中提出的CHNN图像边缘检测算法缺乏足够的参数来调节边缘检测的灵敏度以及检测结果图像边缘过宽的缺陷,提出一种改进的CHNN方法,称之为Weighted CHNN(加权的CHNN,简称WCHNN)方法。该方法在CHNN神经网络元的n个连接上施加权值,可以通过各种局部搜索、优化算法,使用指定的样本输入、样本输出等方法来训练该WCHNN网络从而确定各权值,使得WCHNN在保留了CHNN的优点的同时,还可以根据不同的样本输入输出图像来调节边缘检测的灵敏度,从而提高检测结果质量并避免检测结果中出现边缘过宽的情况。实验结果表明,训练后的WCHNN网络,比起CHNN有着更低的边缘检测错误率,并可检出原来CHNN方法漏检的边缘。 展开更多
关键词 图像边缘检测 CHNN 人工神经网络 加权参数 参数训练
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Dynamic weighted voting for multiple classifier fusion:a generalized rough set method 被引量:9
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作者 Sun Liang Han Chongzhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期487-494,共8页
To improve the performance of multiple classifier system, a knowledge discovery based dynamic weighted voting (KD-DWV) is proposed based on knowledge discovery. In the method, all base classifiers may be allowed to ... To improve the performance of multiple classifier system, a knowledge discovery based dynamic weighted voting (KD-DWV) is proposed based on knowledge discovery. In the method, all base classifiers may be allowed to operate in different measurement/feature spaces to make the most of diverse classification information. The weights assigned to each output of a base classifier are estimated by the separability of training sample sets in relevant feature space. For this purpose, some decision tables (DTs) are established in terms of the diverse feature sets. And then the uncertainty measures of the separability are induced, in the form of mass functions in Dempster-Shafer theory (DST), from each DTs based on generalized rough set model. From the mass functions, all the weights are calculated by a modified heuristic fusion function and assigned dynamically to each classifier varying with its output. The comparison experiment is performed on the hyperspectral remote sensing images. And the experimental results show that the performance of the classification can be improved by using the proposed method compared with the plurality voting (PV). 展开更多
关键词 multiple classifier fusion dynamic weighted voting generalized rough set hyperspectral.
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Multi-mode process monitoring based on a novel weighted local standardization strategy and support vector data description 被引量:9
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作者 赵付洲 宋冰 侍洪波 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第11期2896-2905,共10页
There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because the... There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because their presumptions are that sampled-data should obey the single Gaussian distribution or non-Gaussian distribution. In order to solve these problems, a novel weighted local standardization(WLS) strategy is proposed to standardize the multimodal data, which can eliminate the multi-mode characteristics of the collected data, and normalize them into unimodal data distribution. After detailed analysis of the raised data preprocessing strategy, a new algorithm using WLS strategy with support vector data description(SVDD) is put forward to apply for multi-mode monitoring process. Unlike the strategy of building multiple local models, the developed method only contains a model without the prior knowledge of multi-mode process. To demonstrate the proposed method's validity, it is applied to a numerical example and a Tennessee Eastman(TE) process. Finally, the simulation results show that the WLS strategy is very effective to standardize multimodal data, and the WLS-SVDD monitoring method has great advantages over the traditional SVDD and PCA combined with a local standardization strategy(LNS-PCA) in multi-mode process monitoring. 展开更多
关键词 multiple operating modes weighted local standardization support vector data description multi-mode monitoring
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Blind source separation by weighted K-means clustering 被引量:5
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作者 Yi Qingming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期882-887,共6页
Blind separation of sparse sources (BSSS) is discussed. The BSSS method based on the conventional K-means clustering is very fast and is also easy to implement. However, the accuracy of this method is generally not ... Blind separation of sparse sources (BSSS) is discussed. The BSSS method based on the conventional K-means clustering is very fast and is also easy to implement. However, the accuracy of this method is generally not satisfactory. The contribution of the vector x(t) with different modules is theoretically proved to be unequal, and a weighted K-means clustering method is proposed on this grounds. The proposed algorithm is not only as fast as the conventional K-means clustering method, but can also achieve considerably accurate results, which is demonstrated by numerical experiments. 展开更多
关键词 blind source separation underdetermined mixing sparse representation weighted K-means clustering.
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