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关联噪声驱动的非对称双稳系统的随机共振

物理学报 2008年第4期57卷 2035-2040页

作者：周丙常徐伟西北工业大学应用数学系西安710072

运用统一色噪声近似理论和两态模型理论,研究了周期矩形信号和关联的乘性色噪声和加性白噪声驱动的非对称双稳系统的随机共振现象,得到了适合信号任意幅值的信噪比表达式.信噪比是乘性噪声强度、加性噪声强度、乘性噪声自关联时间、噪... 详细信息

运用统一色噪声近似理论和两态模型理论,研究了周期矩形信号和关联的乘性色噪声和加性白噪声驱动的非对称双稳系统的随机共振现象,得到了适合信号任意幅值的信噪比表达式.信噪比是乘性噪声强度、加性噪声强度、乘性噪声自关联时间、噪声耦合强度的非单调函数,所以该双稳系统中出现了随机共振.同时,调节加性噪声强度比调节乘性噪声强度更容易产生随机共振.势阱静态非对称性和噪声之间的耦合强度对信噪比的影响是不同的.

关键词：非对称双稳系统随机共振信噪比周期矩形信号

电子回旋波使磁镜中捕获电子与逃逸电子相互转化

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物理学报 1993年第8期42卷 1257-1265页

作者：周小兵赵长林核工业西南物理研究院成都610041

在Littlejohn的带电粒子引导中心拉格朗日体系下,讨论了电子回旋波对磁镜等离子体中捕获电子与逃逸电子的影响,给出了捕获电子变成逃逸电子以及逃逸电子被电子回旋波捕获的条件,并计算了它们的相互转化的概率。

关键词：等离子体约束磁镜电子回旋波

Asymptotically Optimal and Admissible Empirical Bayes Estimation of Normal Parameter

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Chinese Quarterly Journal of Mathematics 2007年第1期22卷 1-6页

作者： LIU Huan-xiang SHI Yi-min ZHANG Su-mei zhou bing-chang Department of Mathematica Shaoxing College of Arts and Science Shaoxing 312000 China Department of Applied Mathematics Northwestern Polytechnical University Xi＇an 710072 China

Under square loss, this paper constructs the empirical Bayes（EB） estimation for the parameter of normal distribution which has both asymptotic optimality and admissibility. Moreover, the convergence rate of the EB e... 详细信息

关键词： empirical Bayes estimation asymptotic optimality admissibility

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色高斯噪声驱动双稳系统的多重随机共振研究

物理学报 2011年第6期60卷 162-167页

作者：张晓燕徐伟周丙常西北工业大学应用数学系西安710072

研究了由色关联乘性和加性色噪声作用下的双稳系统的随机共振问题,在绝热近似条件下得到了信噪比的表达式.通过分析所得的初始条件为x(0)=x+时的信噪比,发现了单随机共振和多重随机共振现象;分析了噪声强度、噪声关联时间和关联强度对... 详细信息

研究了由色关联乘性和加性色噪声作用下的双稳系统的随机共振问题,在绝热近似条件下得到了信噪比的表达式.通过分析所得的初始条件为x(0)=x+时的信噪比,发现了单随机共振和多重随机共振现象;分析了噪声强度、噪声关联时间和关联强度对系统信噪比的影响.

关键词：多重随机共振信噪比双稳模型色关联色噪声

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试论水利工程档案业务指导

山西档案 2012年第3期 69-71页

作者：周昌兵长江水利委员会网络与信息中心

本文在对水利工程档案业务指导特点进行分析的基础上,阐述了水利工程档案业务指导的内容及其存在问题,并提出了解决问题的若干措施。

关键词：水利工程档案业务指导

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花岗岩热破裂裂隙动态演化特性数值模拟研究

岩土力学 2024年第S01期45卷 694-704页

作者：周长冰闫俊豪李小双绍兴文理学院土木工程学院浙江绍兴312000 绍兴文理学院岩石力学与地质灾害浙江省重点实验室浙江绍兴312000

为揭示不同压力条件下花岗岩热破裂裂隙演化规律,采用数值计算方法,结合细观损伤理论,建立了岩石热-弹性本构模型,提出了适用于Comsol Multiphysics数值计算软件的矿物颗粒形态提取技术。开展了静水压力及单轴压力下花岗岩热破裂数值模... 详细信息

为揭示不同压力条件下花岗岩热破裂裂隙演化规律,采用数值计算方法,结合细观损伤理论,建立了岩石热-弹性本构模型,提出了适用于Comsol Multiphysics数值计算软件的矿物颗粒形态提取技术。开展了静水压力及单轴压力下花岗岩热破裂数值模拟研究,分析了拉伸和剪切裂隙动态发育过程。研究结果表明:花岗岩内矿物热破裂顺序依赖于各自的力学特性、强度,3种矿物的破裂顺序为云母、长石、石英,热破裂裂隙网络由拉伸裂隙和剪切裂隙组成,拉伸裂隙的发育主导了裂缝网络形成。裂隙演化可划分为3个阶段:微裂隙萌生阶段、裂隙爆发阶段、稳定增长阶段。热破裂阈值受最小主应力控制,单轴压力对阈值的影响较小,受静水压力的影响较大。静水压力下裂隙发育没有明显的方向性,单轴压力压扩展方向垂直于最小主应力,压力越大方向性越明显。

关键词：花岗岩热破裂数值计算裂隙扩展

Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong Liu Siyu Zhang Dan Qu Xuejiao zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi zhou Kai Tao Mengyang Li bing Wei Hongjing Wu Mengyang Li bing Wei Hongjing Wu School of Physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced Materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication Engineering Xidian UniversityXi’an 710071People’s Republic of China MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The Ministry of Education Key Laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption

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有偏总体的极差控制图

数学的实践与认识 2007年第6期37卷 89-93页

作者：周丙常袁可红西北工业大学应用数学系陕西西安710072 洛阳工业高等专科学校计算机系河南洛阳471003

根据加权标准差方法建立有偏总体的极差控制图,它基于有偏总体来计算对应于正态分布的控制图常数,根据样本数据的偏度来计算上下控制限,对于总体是对称分布,该控制图退化为标准的休哈特控制图.最后,用蒙特卡洛方法给出了改进的控制图常数.

关键词：极差控制图有偏总体蒙特卡洛模拟对称分布

Electrode/Electrolyte Optimization‑Induced Double‑Layered Architecture for High‑Performance Aqueous Zinc‑(Dual)Halogen Batteries

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Nano-Micro Letters 2025年第3期17卷 121-137页

作者： Chengwang zhou Zhezheng Ding Shengzhe Ying Hao Jiang Yan Wang Timing Fang You Zhang bing Sun Xiao Tang Xiaomin Liu School of Textiles and Clothing School of Chemistry and Chemical EngineeringQingdao UniversityQingdao 266071ShandongPeople’s Republic of China Centre for Clean Energy Technology School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyUltimoNSW 2007Australia School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007HenanPeople’s Republic of China

Aqueous zinc-halogen batteries are promising candidates for large-scale energy storage due to their abundant resources,intrinsic safety,and high theoretical ***,the uncontrollable zinc dendrite growth and spontaneous shuttle effect of active species have prohibited their practical ***,a double-layered protective film based on zinc-ethylenediamine tetramethylene phosphonic acid(ZEA)artificial film and ZnF2-rich solid electrolyte interphase(SEI)layer has been successfully fabricated on the zinc metal anode via electrode/electrolyte synergistic *** ZEA-based artificial film shows strong affinity for the ZnF2-rich SEI layer,therefore effectively suppressing the SEI breakage and facilitating the construction of double-layered protective film on the zinc metal *** double-layered architecture not only modulates Zn2+flux and suppresses the zinc dendrite growth,but also blocks the direct contact between the metal anode and electrolyte,thus mitigating the corrosion from the active *** employing optimized metal anodes and electrolytes,the as-developed zinc-(dual)halogen batteries present high areal capacity and satisfactory cycling *** work provides a new avenue for developing aqueous zinc-(dual)halogen batteries.

关键词： Zn metal anodes Double-layered protective film Electrode/electrolyte optimization Aqueous zinc-(dual)halogen batteries