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Cosmological evolution of quintessence with a sign-changing interaction in dark sector

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Science China(Physics,Mechanics & Astronomy) 2014年第9期57卷 1805-1808页

作者： ZHANG Ming SUN ChengYi yang zhanying YUE RuiHong Department of Physics Northwest University Institute of Modern Physics Northwest University Faculty of Science Ningbo University

Dark energy and dark matter are only indirectly measured though their gravitational *** is possibie that there is some direct,non-gravitational interaction between DE and DM,which can be used to solve(or,at least alleviate)several important theoretical *** the present work,by analysing the cosmological dynamical system with a dark-sector interaction which changes its sign during the cosmological evolution,we find a scaling attractor to help to alleviate the cosmic-coincidence *** result shows that this interaction can bring new features to the cosmology.

关键词： cosmological evolution scaling attractor dark sector quintessence

A Note on Homogenization of the Hyperbolic-Parabolic Equations in Domains with Holes

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Journal of Mathematical Research with Applications 2016年第4期36卷 485-494页

作者： zhanying yang Xianhe ZHAO School of Mathematics and Statistics South-Central University for Nationalities College of Mathematics and Information Science Henan Normal University

In this paper, we study a class of hyperbolic-parabolic problems in periodically perforated domains with a homogeneous Neumann condition on the boundary of holes. We focus on the homogenization of these equations, which generalizes those achieved by BensoussanLions-Papanicolau and Migorski. The proof is based on the periodic unfolding method in perforated domains.

关键词： hyperbolic-parabolic equations perforated domains homogenization periodic unfolding method

抽水蓄能电站地下厂房施工期污染物运移规律及通风效果研究

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水力发电 2024年第10期50卷 74-79,84页

作者：杨战营马喜峰任韬哲马越冯迪河北抚宁抽水蓄能有限公司河北秦皇岛066006 国网新源控股有限公司抽水蓄能技术经济研究院北京100761 河海大学土木与交通学院江苏南京210024

抽水蓄能电站地下厂房常使用钻爆法施工,易产生大量粉尘与有害气体等污染物,且由于地下厂房首层修建时各洞室未贯通,通风情况不利,污染物往往难以及时排出。为了揭示地下厂房内污染物运移规律,对比不同通风方案的通风效果,使用计算流体... 详细信息

抽水蓄能电站地下厂房常使用钻爆法施工,易产生大量粉尘与有害气体等污染物,且由于地下厂房首层修建时各洞室未贯通,通风情况不利,污染物往往难以及时排出。为了揭示地下厂房内污染物运移规律,对比不同通风方案的通风效果,使用计算流体力学软件Fluent对地下厂房爆破通风过程中的污染物进行了三维非稳态气固两相流耦合数值模拟,分析了厂房内部流场分布规律和不同通风方案下厂房内污染物动态运移规律。结果表明,厂房内部风流场主要包含射流区、附壁流动区、涡流区和回流区等部分;粉尘运移过程出现糅合区、过渡沉降层、积聚峰等区域;爆破后初期,CO易受粉尘的流场耦合作用,随着通风的持续,CO出现壁面慢速扩散区,最终形成一条明确的运移路径;2号通风方案下的污染物运移距离优于1号通风方案,但粉尘出现分布聚集点,若同时使用粉尘净化系统,可在爆破后30 min内完成粉尘的净化,有效解决粉尘聚集问题。

关键词：地下厂房施工通风数值模拟污染物运移粉尘净化抚宁抽水蓄能电站

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论当代中国利益团体的形成与发展

社会主义研究 2002年第3期 52-54页

作者：杨占营海军指挥学院政治指挥系江苏南京210016

随着现代化进程的不断深入 ,中国社会的组织结构正在发生巨大变化 ,考察这一变化无疑有着重要的现实意义。本文在评述了理论界对当前我国利益团体分析的若干观点之后 ,着重阐述了中国利益团体的产生及现状 ,强调了中国利益团体在现阶段... 详细信息

随着现代化进程的不断深入 ,中国社会的组织结构正在发生巨大变化 ,考察这一变化无疑有着重要的现实意义。本文在评述了理论界对当前我国利益团体分析的若干观点之后 ,着重阐述了中国利益团体的产生及现状 ,强调了中国利益团体在现阶段的主要特征 ,并以积极的视角展望了其前景。

关键词：利益团体现代化公民社会法团主义制度供给自组织二元化资源市场化

An Underwater Target Detection Algorithm Based on Attention Mechanism and Improved YOLOv7

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Computers, Materials & Continua 2024年第2期78卷 2829-2845页

作者： Liqiu Ren zhanying Li Xueyu He Lingyan Kong Yinghao Zhang College of Information Science and Engineering Dalian Polytechnic UniversityDalian116034China

For underwater robots in the process of performing target detection tasks,the color distortion and the uneven quality of underwater images lead to great difficulties in the feature extraction process of the model,which is prone to issues like error detection,omission detection,and poor ***,this paper proposed the CER-YOLOv7(CBAM-EIOU-RepVGG-YOLOv7)underwater target detection *** improve the algorithm’s capability to retain valid features from both spatial and channel perspectives during the feature extraction phase,we have added a Convolutional Block Attention Module(CBAM)to the backbone *** Reparameterization Visual Geometry Group(RepVGG)module is inserted into the backbone to improve the training and inference *** Efficient Intersection over Union(EIoU)loss is also used as the localization loss function,which reduces the error detection rate and missed detection rate of the *** experimental results of the CER-YOLOv7 algorithm on the UPRC(Underwater Robot Prototype Competition)dataset show that the mAP(mean Average Precision)score of the algorithm is 86.1%,which is a 2.2%improvement compared to the *** feasibility and validity of the CER-YOLOv7 are proved through ablation and comparison experiments,and it is more suitable for underwater target detection.

关键词： Deep learning underwater object detection improved YOLOv7 attention mechanism

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超Liouville模型精确解

高能物理与核物理 2000年第2期24卷 91-97页

作者：杨战营赵柳甄翼西北大学现代物理研究所西安 710069

运用Leznov -Saveliev代数分析方法和Drinfeld -Sokolov构造分别给出超协变形式和分量形式超Liouville模型精确解 .

关键词：超Liouville模型超代数共形场论量子化统计力学超弦理论费米面求和 Leznov-Saneliev代数分析法李代数

非线性光学系统中呼吸子前沿发展现状(特邀)

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光子学报 2022年第10期51卷 277-289页

作者：杨战营吴玉涵西北大学物理学院西安710127 陕西省理论物理前沿重点实验室西安710127 彭桓武高能基础理论研究中心西安710127

呼吸子泛指一类具有周期演化或周期分布结构的非线性波,它已成为非线性光学系统的研究热点之一。介绍了多种呼吸子在时域和频域空间中的动力学特性,讨论了其历史发展与实际物理意义。通过分析调制不稳定性与呼吸子之间的关系,讨论了呼... 详细信息

呼吸子泛指一类具有周期演化或周期分布结构的非线性波,它已成为非线性光学系统的研究热点之一。介绍了多种呼吸子在时域和频域空间中的动力学特性,讨论了其历史发展与实际物理意义。通过分析调制不稳定性与呼吸子之间的关系,讨论了呼吸子的激发机制及不同呼吸子之间的定量转换关系。由于呼吸子间存在多种相互作用形式,还讨论了由呼吸子碰撞诱发的高振幅波、Superregular呼吸子等过程。这些结果有助于读者对非线性系统中呼吸子动力学的理解,并进一步探究和实现光学呼吸子的实际应用与可控激发。

关键词：非线性光学呼吸子怪波动力学激发机制相互作用

First-principles study of the relationship between the formation of single atom catalysts and lattice thermal conductivity

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Chinese Chemical Letters 2024年第6期35卷 502-506页

作者： Chaozheng He Pei Shi Donglin Pang zhanying Zhang Long Lin Yingchun Ding Department of Chemistry and Chemical Engineering Liaocheng UniversityLiaocheng 252059China Henan Key Laboratory of Materials on Deep-Earth Engineering School of Materials Science and EngineeringHenan Polytechnic UniversityJiaozuo 454000China School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454000China Department of Basic Medicine North Sichuan Medical CollegeNanchong 637000China

Single atom catalysts(SACs)have been in the forefront of catalysts research because of their high efficiency and low cost and provide new ideas for development of renewable energy conversion and storage ***,the relationship between the intrinsic properties of materials such as lattice thermal conductivity and catalysis remains to be *** this work,the lattice thermal conductivity of BN and graphene was calculated by Sheng *** addition,the adsorption properties of 3d-TM(TM=V,Cr,Mn,Fe,Co,Ni)on BN and graphene were investigated using first-principles methods,and it was found that Ni atom can form relatively stable SACs compared to other *** molecular dynamics(MD)simulation and migration barrier of Ni loaded on BN and graphene were *** study found that graphene has higher thermal conductivity and is easier to form SACs than BN,but the SACs formed on BN surface have higher thermodynamic stability.

关键词： First-principles calculation Thermal conductivity Single atom catalysts Graphene BN

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电磁感应透明介质的高阶非线性特性

光学学报 2014年第6期34卷 260-265页

作者：杜英杰杨战营白晋涛西北大学物理学系陕西西安710069 西北大学光子学与光子技术研究所陕西西安710069

在理论上研究了电磁感应透明(EIT)介质的高阶非线性特性。引入一种区别于迭代法的新方法,该方法基于暗共振的分布情况,得到跃迁密度矩阵元的全解,在此基础上得到原子体系对探针光的各阶响应。研究结果表明,线性(一阶)极化率表现破坏性相... 详细信息

在理论上研究了电磁感应透明(EIT)介质的高阶非线性特性。引入一种区别于迭代法的新方法,该方法基于暗共振的分布情况,得到跃迁密度矩阵元的全解,在此基础上得到原子体系对探针光的各阶响应。研究结果表明,线性(一阶)极化率表现破坏性相干,非线性(三阶)极化率表现建设性相干;在各向同性介质中偶数阶次的非线性响应消失。进一步研究发现,五阶极化率和线性极化率一样呈现破坏性相干。研究结果为探索光波在EIT介质传输过程中高阶非线性对光波演化的影响提供了理论依据。该方法为研究高阶非线性效应提供了一种新的理论途径。

关键词：量子光学高阶非线性电磁感应透明解析法迭代法