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A Positive Solution for Some Critical p-Laplacian Systems

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Acta Mathematica Sinica,English Series 2015年第3期31卷 479-500页

作者： Xiao zhi wang College of Science University of Shanghai for Science and Technology

This paper deals with the existence of a positive solution for two classes of critical quasilinear system. We prove these results by a variant of mountain pass lemma, combining two convergence theorems and two estimate results. Here we avoid the usual compactness arguments（e.g., Palais-Smale condition or Cerami condition） and reveal the potential of some energy level estimates for the existence of nontrivial solutions.

关键词： p-Laplacian system critical growth convergence theorem estimate result

Radiative Decays of (0^+,1^+) Strange-Bottom Mesons

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Communications in Theoretical Physics 2009年第7期52卷 91-98页

作者： wang zhi-Gang Department of Physics North China Electric Power University Baoding 071003 China

In this article, we assume that the （0^＋,1^＋） strange-bottom mesons are the conventional bs mesons, and calculate the electromagnetic coupling constants d, g1, g2, and g3 using the light-cone QGD sum rules. Then we study the radiative decays Bs0→Bs^＊γ, Bs1→Bsγ, Bs1→Bs^＊γ, and Bs1→Bs0γ, and observe that the widths are rather narrow. We can search for the （0^＋, 1^＋） strange-bottom mesons in the invariant Bsπ^0 and Bs^＊π^0 mass distributions in the strong decays or in the invariant Bs^＊γ, and Bsγ mass distributions in the radiative decays.

关键词： strange-bottom mesons light-cone QCD sum rules

Yang-Lee Circle Theorem for an Antiferromagnetic Heisenberg Ladder

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Chinese Physics Letters 2001年第7期18卷 953-954页

作者： wang Xian-zhi Department of Physics Shanghai Jiao Tong UniversityShanghai 200030

The Yang-Lee zeros of an antiferromagnetic Heisenberg ladder model are *** is found that if J_(4)≤0 Yang-Lee zeros are located on the unit circle and on the negative real axis in the complex activity *** particular,if J_(4)≤0 and 2J_(2)≥J_(4),Yang-Lee zeros are located on the unit circle and Yang-Lee circle theorem is *** J_(4)>0,Yang Lee zeros are locted on some complicated curves.

关键词： Heisenberg circle plane.

Derivation of the Bosonic Part of the Electroweak Chiral Lagrangian from a General Underlying Technicolor Theory

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Communications in Theoretical Physics 2001年第10期36卷 417-426页

作者： wang zhi-Min wang Qing Department of Physics Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 ChinaCCAST World Laboratory P.O. Box 8730 Beijing 100080 China Institute of Theoretical Physics Academia Sinica Beijing 100080 China

Bosonic part of SU(2)L U(1)Y effective chiral Lagrangian for electroweak symmetry breaking is derived from an underlying technicolor theory with no approximation. The underlying theory is assumed to be the most general gauge theory without fundamental scalars. A condensate is required to exist in the theory which breaks SU(2)L U(1)Y dynamically to U(1)em and the anomaly of the theory caused by gauge interaction must be cancelled. The formulation offers general definitions in terms of underlying theory for the low energy constants in effective chiral Lagrangian.

关键词： chiral Lagrangian, electroweak symmetry, technicolor, derivation

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基于荧光光谱和拉曼光谱技术的中药检测研究

光谱学与光谱分析 2025年第1期45卷 139-145页

作者：逯美红张凡暴雅婷王志军雷海英王翔宇高鹏慧长治学院物理系山西长治046011 西安信息职业大学物理实验中心陕西西安710125 长治学院生命科学系山西长治046011

中医药是中华文化的瑰宝和中华文明的结晶,在全民健康中发挥着重要作用。由于中药生长环境受限及市场需求量的增大,市场上出现了许多以次充好、以假乱真的中药,这对中药发展及质量保障都极为不利。因此,对中药的检测和鉴定非常重要。为... 详细信息

中医药是中华文化的瑰宝和中华文明的结晶,在全民健康中发挥着重要作用。由于中药生长环境受限及市场需求量的增大,市场上出现了许多以次充好、以假乱真的中药,这对中药发展及质量保障都极为不利。因此,对中药的检测和鉴定非常重要。为了探究中药的荧光光谱和拉曼光谱特性,选取白芷、苏木、山药、地榆四种中药进行分类检测研究。一方面,从化学成分和结构的角度分析中药白芷和苏木产生荧光的可能性,采用F-4600型荧光光谱仪(200~750 nm)分别在不同激发波长和不同浓度下测试了白芷和苏木水浸液的荧光光谱,探究了白芷和苏木水浸液的荧光光谱特性,并对荧光强度与不同浓度、激发波长的关系进行了探讨。另一方面,采用共聚焦显微拉曼光谱仪(100~4000 cm^(-1))对4种不同产地的山药和2种不同产地的地榆中药饮片的拉曼光谱分别进行测试研究。结果表明,白芷水浸液在波长260~350 nm的光激发下,产生较强荧光,最佳激发波长是340 nm,荧光峰值波长为420 nm,其荧光强度随浓度的增大而增强,且样品浓度较低时,荧光强度与浓度成线性关系;苏木水浸液在200~290 nm的光激发下,产生较强荧光,最佳激发波长为220 nm,荧光峰值波长为345 nm,随浓度的增加,荧光强度先增强后减弱,在浓度为0.175 mg·mL^(-1)时荧光强度达到最大。白芷水浸液和苏木水浸液的荧光强度都与激发波长的关系呈现高斯分布,符合荧光规律。分析山药和地榆的拉曼光谱,发现不同产地的拉曼特征基本一致,确认山药的拉曼特征峰主要集中在477、862、939、1080、1258、1337和1457 cm^(-1)处;地榆的拉曼特征峰主要集中在862和1337 cm^(-1)处,主要归属与已有的化学成分研究结果相符。部分特征峰处拉曼活性出现差异,可以作为区分不同产地中药的依据。该研究结果不仅为荧光光谱在中药鉴定及质量分析中的应用提供了实验数据和方法参考,也为利用拉曼光谱技术实现中药的快速准确检测及产地归属奠定了基础。

关键词：白芷苏木山药地榆荧光光谱拉曼光谱

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

Analysis of Mass Difference of the π and ρ with Bethe–Salpeter Equation

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Chinese Physics Letters 2011年第8期28卷 39-42页

作者： wang zhi-Gang Department of Physics North China Electric Power UniversityBaoding 071003

PDF(474KB)Export:BibTeX|EndNote|Reference Manager|ProCite|RefWorks Abstract The one-pion exchange force in addition to the one-gluon exchange force is taken into account to study the mass difference of theπandρmesons with the Bethe–Salpeter *** projecting the Bethe–Salpeter equation into a simple form,it can be seen explicitly that the bound energy|Eπ|≫|Eρ|.

关键词： equation Bethe exchange

An Implicit Coupled 1D/2D Model for Unsteady Subcritical Flow in Channel Networks and Embayment

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China Ocean Engineering 2020年第1期34卷 110-118页

作者： GENG Yan-fen wang zhi-li School of Transportation Southeast UniversityNanjing 211189China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210024China

In this study, 1D and 2D shallow-water models were coupled to simulate unsteady flow in channel networks and embayment. The 1D model solved the 1D shallow-water equations (St. Venant) using the Preissmann box method and targeted long narrow reaches of the river networks, while the 2D model targeted broad channels and embayment and solved the 2D shallow-water equations using a semi-implicit scheme applied to an unstructured grid of triangular cells. The 1D and 2D models were solved simultaneously by building a matrix for the free surface elevation at every 1D junction and 2D cell center. Velocities were then computed explicitly based on the results at the previous time step and the updated water level. The originality of the scheme arose from a novel coupling method. The results showed that the coupled 1D/2D model produced identical results as the full 2D model in classical to benchmark problems with considerable savings in computational effort. Application of the model to the Pearl River Estuary in southern China showed that complex patterns of tidal wave propagation could be efficiently modeled.

关键词： 1D river network model 2D unstructured model full coupling model Pearl River Delta

A fusion of least squares and empirical likelihood for regression models with a missing binary covariate

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Science China Mathematics 2016年第10期59卷 2027-2036页

作者： DUAN XiaoGang wang zhi Department of Statistics Beijing Normal UniversityBeijing 100875China

Multiply robust inference has attracted much attention recently in the context of missing response data. An estimation procedure is multiply robust, if it can incorporate information from multiple candidate models, and meanwhile the resulting estimator is consistent as long as one of the candidate models is correctly specified. This property is appealing, since it provides the user a flexible modeling strategy with better protection against model misspecification. We explore this attractive property for the regression models with a binary covariate that is missing at random. We start from a reformulation of the celebrated augmented inverse probability weighted estimating equation, and based on this reformulation, we propose a novel combination of the least squares and empirical likelihood to separately handle each of the two types of multiple candidate models,one for the missing variable regression and the other for the missingness mechanism. Due to the separation, all the working models are fused concisely and effectively. The asymptotic normality of our estimator is established through the theory of estimating function with plugged-in nuisance parameter estimates. The finite-sample performance of our procedure is illustrated both through the simulation studies and the analysis of a dementia data collected by the national Alzheimer's coordinating center.

关键词： calibration covariate adjustment effect modification missing at random multiple robustness refitting