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Joint application of feature extraction based on EMD-AR strategy and multi-class classifier based on LS-SVM in EMG motion classification

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1246-1255页

作者： YAN zhi-guo wang zhi-zhong REN Xiao-mei Departmen of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200030 China

This paper presents an effective and efficient combination of feature extraction and multi-class classifier for motion classification by analyzing the surface electromyografic(sEMG) signals. In contrast to the existing methods,considering the non-stationary and nonlinear characteristics of EMG signals,to get the more separable feature set,we introduce the empirical mode decomposition(EMD) to decompose the original EMG signals into several intrinsic mode functions(IMFs) and then compute the coefficients of autoregressive models of each IMF to form the feature set. Based on the least squares support vector machines(LS-SVMs) ,the multi-class classifier is designed and constructed to classify various motions. The results of contrastive experiments showed that the accuracy of motion recognition is improved with the described classification scheme. Furthermore,compared with other classifiers using different features,the excellent performance indicated the potential of the SVM techniques embedding the EMD-AR kernel in motion classification.

关键词： Electromyografic signal Empirical mode decomposition (EMD) Auto-regression model Wavelet packet transform Least squares support vector machines (LS-SVM) Neural network

浅析大规格楸树圃地苗抚育管理技术——以界首市为例

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园艺与种苗 2024年第5期44卷 3-4,35页

作者：王治中闫彩霞界首市苗圃安徽界首236500 安徽省林业科学研究院安徽合肥230088

基于楸树生物学特性,以界首市为例,阐述了大规格楸树圃地苗的抚育管理技术和要点。通过做好松土除草和水肥管理工作、科学定植与施肥、针对性地开展病虫害防治,为培育优质大规格楸树壮苗提供科学依据。

关键词：楸树圃地苗抚育管理

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Some generalized limit theorems concerning delayed sums of random sequence

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Applied Mathematics(A Journal of Chinese Universities) 2013年第1期28卷 40-48页

作者： wang zhong-zhi YANG Wei-guo SHI zhi-yan School of Mathematics & Physics AnHui University of Technology Faculty of Science Jiangsu University

For a sequence of arbitrarily dependent m-valued random variables （Xn） n∈N , the generalized strong limit theorem of the delayed average is investigated. In our proof, we improved the method proposed by Liu [6] . A... 详细信息

关键词： Limit theorem delayed average Borel-Cantelli lemma inhomogeneous Markov chain.

Multifractal analysis of surface EMG signals for assessing muscle fatigue during static contractions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 910-915页

作者： wang Gang REN Xiao-mei LI Lei wang zhi-zhong Department of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200240 China

This study is aimed at assessing muscle fatigue during a static contraction using multifractal analysis and found that the surface electromyographic （SEMG） signals characterized multiffactality during a static contraction. By applying the method of direct determination ofthef（a） singularity spectrum, the area of the multifractal spectrum of the SEMG signals was computed. The results showed that the spectrum area significantly increased during muscle fatigue. Therefore the area could be used as an assessor of muscle fatigue. Compared with the median frequency （MDF）--the most popular indicator of muscle fatigue, the spectrum area presented here showed higher sensitivity during a static contraction. So the singularity spectrum area is considered to be a more effective indicator than the MDF for estimating muscle fatigue.

关键词： Muscle fatigue Surface electromyographic (SEMG) signals Multifractal Static contraction

准噶尔盆地玛西斜坡八道湾组一段厚层砂砾岩储层评价及强非均质控藏特征

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科学技术与工程 2024年第23期24卷 9718-9728页

作者：齐洪岩李小石王智忠王爱霞赵晓东中国石油新疆油田公司勘探开发研究院克拉玛依834000 中国石油大学(北京)克拉玛依校区石油学院克拉玛依834000

准噶尔盆地侏罗系是增储上产的主力层系,其中玛湖凹陷西斜坡(简称“玛西斜坡)侏罗系八道湾组一段主要为低孔低渗砂砾岩储层,玛西斜坡同一套储层(构造、沉积、成岩条件类似)有的成藏、有的未成藏,亟需开展砂砾岩储层评价,明确控藏特征。... 详细信息

准噶尔盆地侏罗系是增储上产的主力层系,其中玛湖凹陷西斜坡(简称“玛西斜坡)侏罗系八道湾组一段主要为低孔低渗砂砾岩储层,玛西斜坡同一套储层(构造、沉积、成岩条件类似)有的成藏、有的未成藏,亟需开展砂砾岩储层评价,明确控藏特征。利用岩心、薄片、分析化验、试油试产等资料,进行玛西斜坡八道湾组一段厚层砂砾岩储层评价,重点开展储层非均质评价明确非均质控藏特征。研究结果表明:①玛西斜坡八道湾组一段主要发育厚层砂砾岩储层,为辫状河道沉积,储层中主要发育泥质、致密砂岩层、钙质与煤层等4种隔夹层,隔夹层在纵向上增强了储层非均质性;②玛西斜坡八道湾组一段储层孔隙度分布范围2.9%~18.8%,平均孔隙度为10.60%,渗透率分布范围是0.02×10^(-3)~255×10^(-3)μm^(2),平均渗透率为3.29×10^(-3)μm^(2),其中砂砾岩储层孔隙度分布范围4.1%~15.8%,平均为8.27%,渗透率分布范围是0.05×10^(-3)~145×10^(-3)μm^(2),平均值1.24×10^(-3)μm^(2),属于特低孔特低渗储层,储层具有孔喉半径较小,孔隙结构复杂,喉道连通性较差,排驱压力高的特征;③建立起储集空间与含油性的关系,储集空间发育、非均质性弱的层段含油性差,而储集空间弱发育、非均质性强的层段含油性好,储层非均质性是控制准噶尔盆地玛西斜坡八道湾组厚层砂砾岩储层油气成藏的主控因素;④利用数据包络法计算了玛西斜坡八道湾组一段厚层砂砾岩储层非均质指数,主要介于0.621~0.782,属于较强—中等非均质性。试油出油层段储层非均质指数为0.621~0.673,为较强非均质性储层,试油未或少出油层段储层非均质指数为0.674~0.782,为中等非均质性储层。结论认为储层非均质性对玛西斜坡八道湾组一段厚层砂砾岩储层油气成藏具有控制作用,强非均质储层中油气难以逸散而得到保存,油藏主要富集在强非均质储层中。

关键词：准噶尔盆地玛湖凹陷西斜坡砂砾岩储层储层非均质性非均质指数

Oil-gas reservoir lithofacies stochastic modeling based on one- to three-dimensional Markov chains

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Journal of Central South University 2018年第6期25卷 1399-1408页

作者： wang zhi-zhong HUANG Xiang LIANGYu-ru School of Mathematics and Statistics Central South UniversityChangsha 410012China Data Center（Beijing） Agricultural Bank of ChinaBeijing 100161China Department of Railway Locomotive and Electromechanical Equipment Shandong PolytechnicJi＇nan 250104China ~ Central South University Press and Springer-Verlag GmbH Germanypart of Springer Nature 201

Stochastic modeling techniques have been widely applied to oil-gas reservoir lithofacies. Markov chain simulation~ however~ is still under development~ mainly because of the difficulties in reasonably defining conditional probabilities for multi-dimensional Markov chains and determining transition probabilities for horizontal strike and dip directions. The aim of this work is to solve these problems. Firstly~ the calculation formulae of conditional probabilities for multi-dimensional Markov chain models are proposed under the full independence and conditional independence assumptions. It is noted that multi-dimensional Markov models based on the conditional independence assumption are reasonable because these models avoid the small-class underestimation problem. Then~ the methods for determining transition probabilities are given. The vertical transition probabilities are obtained by computing the transition frequencies from drilling data~ while the horizontal transition probabilities are estimated by using well data and the elongation ratios according to Walther＇s law. Finally~ these models are used to simulate the reservoir lithofacies distribution of Tahe oilfield in China. The results show that the conditional independence method performs better than the full independence counterpart in maintaining the true percentage composition and reproducing lithofacies spatial features.

关键词： independence assumption Markov chain reservoir lithofacies small-class underestimation transitionprobability

Broadband Source Ranging in Shallow Water Using the Ω-Interference Spectrum

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Chinese Physics Letters 2010年第6期27卷 110-113页

作者： ZHAO Zhen-Dong wang Ning GAO Da-zhi wang Hao-zhong College of Information Science and Engineering Ocean University of China Qingdao 266100

The concept of the waveguide invariant is revisited and a simple relationship between the range of source and the quasi-period of the acoustic interference spectrum in the frequency domain （Ω-interference spectrum） is derived. Then a method for a broadband source ranging in shallow water using a single receiver and a broadband guide source, requiring no modeling and no knowledge about the ocean environment, is proposed. The method is validated by simulation and verified with the experimental data.

关键词： Methods Broadband Source Ranging Ω-Interference Spectrum

Clinical efficacies of treating refractory insomnia patients with estazolam plus alternating current magnetic field

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Chinese Medical Journal 2012年第17期125卷 3175-3176页

作者： wang zhi-zhong wang Ya-ping WAN Jun-ping wang Jing Third Department of Outpatient Services Beijing Military General HospitalBeijing 100700China

As one of common physical and mental ailments, insomnia may cause serious adverse effects on a patient＇s daily life. And serious accidents occur in long-term cases.1 Despite comprehensive treatments, 9.38%-17.0% of the treated insomniacs fail to benefit at all. Thus the term of ＂refractory insomnia＂ has been coined.24 At present, there is no literature reporting the roles of estazolam plus alternating current magnetic field （ACMF） for treating insomnia. In the present study, estazolam plus ACMF was employed for the patients with refractory insomnia so as to explore the clinical efficacies of such a combined modality.

关键词： estazolam alternating current magnetic field refractory insomnia Pittsburg sleep quality index

On Strong Law of Large Numbers for Random Sequence

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Chinese Quarterly Journal of Mathematics 2010年第4期25卷 475-480页

作者： wang zhong-zhi Faculty of Mathematics and Physics Anhui University of TechnologyMa＇anshan 243002China

This note is devoted to introduce a new concept of conditionally dominated random *** suitable restrict conditions,a general strong law of large numbers for arbitrary continuous random variables is obtained.

关键词： random variable strong law of large numbers conditionally dominated random sequence