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Transition to Amplitude Death in Coupled System with Small Number of Nonlinear Oscillators

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Communications in Theoretical Physics 2009年第3期51卷 460-464页

作者： CHEN hai-Ling yang Jun-zhong School of Science Beijing University of Posts and Telecommunications Beijing 100876 China

In this work, we investigate the amplitude death in coupled system with small number of nonlinear oscillators. We show how the transitions to the partial and the complete amplitude deathes happen. We also show that th... 详细信息

关键词： coupled nonlinear oscillators amplitude death phase synchronization

Properties of multi-Gaussian Schell-model beams carrying an edge dislocation propagating in oceanic turbulence

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Chinese Physics B 2019年第10期28卷 360-366页

作者： Da-Jun Liu Yao-Chuan Wang Gui-Qiu Wang Hong-Ming Yin hai-yang zhong Department of Physics College of Science Dalian Maritime University

Based on the theory of coherence, the model of multi-Gaussian Schell-model(MGSM) beams carrying an edge dislocation generated by the MGSM source is introduced. The analytical cross-spectral density of MGSM beams carrying an edge dislocation propagating in oceanic turbulence is derived, and used to study the evolution properties of the MGSM beams carrying an edge dislocation. The results indicate that the MGSM beam carrying an edge dislocation propagating in oceanic turbulence will evolve from the profile with two intensity peaks into a flat-topped beam caused by the MGSM source, and the beam will evolve into the Gaussian-like beam due to the influences of oceanic turbulence in the far *** the propagation distance increases, the MGSM beam carrying an edge dislocation propagating in oceanic turbulence with the larger rate of dissipation of mean-squared temperature(χT) and ratio of temperature to salinity contribution to the refractive index spectrum(?) or the smaller rate of dissipation of kinetic energy per unit mass of fluid(ε) evolves into the flat-topped beam or a Gaussian beam faster.

关键词： oceanic turbulence multi-Gaussian Schell-model source edge dislocation laser propagation average intensity

On the Friction and Wear Behaviors of Dental Machinable Porcelain

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材料热处理学报 2004年第05B期25卷 1171-1174页

作者： YUhai-yang ZHOUzhong-rong CAIZhen-Bing TribologyResearchInstitute SouthwestJiaotongUniversityChengduChina TribologyResearchInstitute SouthwestJiaotongUniversityChengduChina／／CollegeofHuaxiStomatologySichuanUniversityChengduChina

In order to well design tribosystems of dental CAD-CAM restorations, an understanding of the tribological mechanisms of dental machinable porcelain are essential. The friction and wear behavior of new generation industrially prefabricated Cerec Vitablocs Mark II against uniform Si3N4 ball has been performed using a small amplitude reciprocating apparatus under simulating oral conditions. The loads of 10-40 N, reciprocating amplitudes of 100-500 urn, frequencies of 1-4 Hz and two lubrications (no / artificial saliva lubrication) were selected. Tests lasting up to 10 000 cycles were conducted. The results show that Cerec Vitablocs Mark II record a friction coefficient of 0.55-0.84. Artificial saliva plays a lubricant effect during wear process. Among three parameters of the test on friction coefficient and wear depth of dental machinable porcelains, the load effect is prominent. Abrasive wear is the main wear mechanism, but brittle cracks and delamination are more popular especially under unlubricated friction.

关键词：磨损性能摩擦系数陶瓷材料齿轮

Erratum to:Asymptotic Tail Probability of Randomly Weighted Sums of Dependent Random Variables with Dominated Variation

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 560-560页

作者： hai-zhong yang School of Statistics Xi'an University of Finance and Economics Xi'an 710100 China

The original version of this article unfortunately contained a mistake. Equation （3.5） should be corrected as follows：

关键词： Erratum to

稀疏组Lasso Granger因果图模型及应用

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统计与信息论坛 2022年第4期37卷 3-12页

作者：高伟杨海忠杨露西安财经大学统计学院陕西西安710100

辨识序列间的因果联系是时间序列分析的主要任务之一。将Granger因果关系的检验问题转换为变量选择问题,应用稀疏组Lasso方法辨识序列间Granger因果关系的存在性和因果影响的滞后阶数。提出了稀疏组Lasso Granger因果图模型,顶点表示多... 详细信息

辨识序列间的因果联系是时间序列分析的主要任务之一。将Granger因果关系的检验问题转换为变量选择问题,应用稀疏组Lasso方法辨识序列间Granger因果关系的存在性和因果影响的滞后阶数。提出了稀疏组Lasso Granger因果图模型,顶点表示多维时间序列的分量序列,顶点间的有向边表示序列间存在的Granger因果关系,定义了滞后信息矩阵揭示因果影响的滞后信息。数值模拟验证了在各种维数和滞后影响结构的模型下,样本量对估计效果的影响。应用到中国宏观经济数据,进行实证分析的结果表明,稀疏组Lasso Granger因果图方法能够较好地揭示序列间的因果关系结构。

关键词： Granger因果关系稀疏组Lasso 图模型向量自回归模型

维普期刊数据库博看期刊

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技术专家治国论话语和学术失范

自然辩证法通讯 2003年第2期25卷 95-100页

作者：蔡海榕杨廷忠杭州师范学院医学院杭州310012

学术失范乃至腐败已成为学术界以至社会普遍关注的焦点问题。技术专家治国论话语的传播,造成了学术的单一化、狭窄化、形式化以及学术管理中的非人本化倾向和部分知识分子特权,成为我国学术失范和学术腐败的原因之一。因此学术研究应超... 详细信息

学术失范乃至腐败已成为学术界以至社会普遍关注的焦点问题。技术专家治国论话语的传播,造成了学术的单一化、狭窄化、形式化以及学术管理中的非人本化倾向和部分知识分子特权,成为我国学术失范和学术腐败的原因之一。因此学术研究应超越技术专家治国论的研究框架,知识分子既应当成为专家又应当坚持特有的人文价值理性和批判精神。

关键词：学术失范批判理性学术腐败知识分子技术专家治国论

Asymptotic for the Finite-Time Ruin Probability in the Renewal Risk Model with Constantinterest Force

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Asymptotic for the Finite-Time Ruin Probability in the Renew...

Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

第七届中国不确定系统年会

作者： hai-zhong yang,Jing Wei School of Statistics,Xi’an University of Finance and Economics,Xi’an 710100,China

Chen and Ng investigated the infinite time ruin probability of the renewal risk model with constant interest and extended regularly varying tailed *** the techniques developed by Chen and Ng,the note derives a simple ... 详细信息

关键词： Asymptotics finite-time ruin probability the renewal risk model

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Journal of Energy Chemistry 2025年第1期100卷 730-738页

作者： Peng Zheng Wang Zhou Ying Mo Biao Zheng Miaomiao Han Qin zhong Wenwen yang Peng Gao Lezhi yang Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology Hunan University Greater Bay Area Institute for Innovation Hunan University Changsha Research Institute of Mining & Metallurgy Co. LTD.

Hard carbon （HC） has been considered as promising anode material for sodium-ion batteries （SIBs）.The optimization of hard carbon’s microstructure and solid electrolyte interface （SEI） property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy （FTIR/EIS） and X-ray photoelectron spectroscopy （XPS） analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： X ray photoelectron spectroscopy

低序级断层识别技术在复杂断块油藏注采调整中的运用

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石油勘探与开发 2006年第5期33卷 614-617,621页

作者：曾祥平杨海中王宏姜开惠中国科学院地质与地球物理研究所中国石化胜利石油管理局孤岛采油厂

孤岛油田南区是被断层复杂化的稠油、疏松砂岩油藏,地质条件复杂,区内共有大小断层13条,将该区切割成11个断块,各主要断块都有自己独立的油水系统,对聚合物驱油产生了不利影响。为了准确识别断裂系统,调整油田的注采对应关系,提高油田... 详细信息

孤岛油田南区是被断层复杂化的稠油、疏松砂岩油藏,地质条件复杂,区内共有大小断层13条,将该区切割成11个断块,各主要断块都有自己独立的油水系统,对聚合物驱油产生了不利影响。为了准确识别断裂系统,调整油田的注采对应关系,提高油田的开发水平,利用小波多尺度边缘检测技术、相干体分析技术对区内的低序级断层进行了多轮解释,重新绘制了该区的断层分布图,并利用干扰试井、动态分析等方法对新解释断裂系统的准确性进行了检验,在此基础上调整了注采对应关系,开展了注聚合物综合调整,聚合物驱增油效果得到明显提高。

关键词：复杂断块低序级断层注采对应关系注聚合物调整