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Feedback maximization of reliability of MDOF quasi integrable-Hamiltonian systems under combined harmonic and white noise excitations

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第9期10卷 1245-1251页

作者： Lin-cong CHEN rong-hua HUAN wei-qiu ZHU Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

We studied the feedback maximization of reliability of multi-degree-of-freedom （MDOF） quasi integrable-Hamiltonian systems under combined harmonic and white noise excitations. First, the partially averaged Ito equations are derived by using the stochastic averaging method for quasi integrable-Hamiltonian systems under combined harmonic and white noise excitations. Then, the dynamical programming equation and its boundary and final time conditions for the control problems of maximizing the reliability is established from the partially averaged equations by using the dynamical programming principle. The nonlinear stochastic optimal control for maximizing the reliability is determined from the dynamical programming equation and control constrains. The reliability function of optimally controlled systems is obtained by solving the final dynamical programming equation. Finally, the application of the proposed procedure and effectiveness of the control strategy are illustrated by using an example.

关键词： Stochastic optimal control Dynamical programming Quasi integrable-Hamiltonian system Stochastic averaging Combined harmonic and white noise excitation Reliability

基于RBF神经网络的主动配电网通信过程安全态势感知方法

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电网与清洁能源 2024年第5期40卷 52-58页

作者：刘威邓巍深圳供电局有限公司广东深圳518000

为提前拦截主动配电网通信过程中的恶意攻击、保证电网稳定运行,提出基于RBF神经网络的通信过程安全态势感知方法。综合考虑电压越限、失负荷、供电能力等因素,筛选主动配电网通信安全态势评价指标;利用非线性基函数实现从输入到输出的... 详细信息

为提前拦截主动配电网通信过程中的恶意攻击、保证电网稳定运行,提出基于RBF神经网络的通信过程安全态势感知方法。综合考虑电压越限、失负荷、供电能力等因素,筛选主动配电网通信安全态势评价指标;利用非线性基函数实现从输入到输出的非线性变换,采用改进ReliefF算法选取网络通信入侵行为特征,并将其作为RBF神经网络的输入量;将主动配电网络节点部署的安全态势数据分割为若干分量,通过参数调整平滑处理安全态势感知数据,再利用双层滤波检测法输出RBF神经网络的感知结果。由试验结果可知:采用该方法时,特征识别准确率为97.61%,安全态势值为0.894,态势感知时间为0.361 s,能有效感知攻击行为,精准呈现网络态势变化,且感知过程用时较短。

关键词： RBF神经网络主动配电网态势感知评价指标平滑处理

Humic-Like Substances from Different Compost Extracts Could Significantly Promote Cucumber Growth

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Pedosphere 2012年第6期22卷 815-824页

作者： XU Da-Bing WANG Qiu-Jun WU yun-Cheng yu Guang-Hui SHEN Qi-rong HUANG Qi-wei Jiangsu Provincial Key Lab for Organic Solid Waste Utilization Nanjing Agricultural UniversityNanjing 210095(China)

The effects of direct extracts of compost (DEC), aerated fermentation extracts of compost (AFEC) and non-aerated fermentation extracts of compost (NAFEC) on cucumber growth and the action mechanisms were evaluated based on the structure and activity analysis of humic-like substances. AFEC increased cucumber growth most significantly, followed by DEC and NAFEC, which was insignificant compared to the control treatment. Humic-like substances from compost extracts played an important role in promoting cucumber growth. Application of humic-like substances stimulated auxin-like activity and increased chlorophyll content and nitrogen accumulation in plants. The positive auxin-like activity of humic-like substances could be attributed to the relative distribution of special carbon groups, such as those with a large amount of peptidic and carbohydratic groups or with a low content of phenolic groups. In conclusion, the best growth promotion by application of AFEC was mainly attributed to the humic-like substances in the AFEC.

关键词： auxin-like activity 13C nuclear magnetic resonance chemical structure elemental composition analysis

Association between body mass index and the risk of bleeding in elderly patients with non-valvular atrial fibrillation taking dabigatran:a cohort study

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Journal of Geriatric Cardiology 2020年第4期17卷 193-201页

作者： Ming-Hui LI Li-Hua HU yu-rong XIONG yu yu wei ZHOU Tao WANG Ling-Juan ZHU Xi LIU Hui-Hui BAO Xiao-Shu CHENG Department of Cardiovascular Medicine the Second Affiliated Hospital of Nanchang UniversityJiangxiChina Center for Prevention and Treatment of Cardiovascular Diseases the Second Affiliated Hospital of Nanchang UniversityJiangxiChina Center of Cardiovascular Inner Mongolia People’s HospitalHohhotInner MongoliaChina

Background Uncertainty remains regarding the association between body mass index(BMI)and the risk of bleeding in patients with non-valvular atrial fibrillation(NVAF).We aimed to investigate the association between BMI and the risk of bleeding in elderly NVAF patients taking *** A total of 509 elderly NVAF patients,who were being treated at twelve centers in China from February 2015 to December 2017 and taking dabigatran,were *** exposure and outcome variables were BMI at baseline and bleeding events within the subsequent six months,*** proportional hazards regression analysis was used to evaluate the association between BMI and the risk of ***,the Cox proportional hazards regression with cubic spline functions and smooth curve fitting was *** During the six-month follow-up,50 participants experienced *** 1 kg/m^2 increase in BMI was associated with a 12%increased risk of bleeding(P=0.021).Compared to those with BMI values in Tertile 1(25.3 kg/m^2)were 2.71(95%CI:1.02–7.17)and 3.5(95%CI:1.21–8.70),*** Ptrend-value was significant in all *** adjusted smooth curve showed a linear association between BMI and *** of the stratified variables showed significant effect modification on the association between BMI and bleeding(Pinteraction>0.05).Conclusions BMI was significantly and positively associated with the risk of bleeding in elderly NVAF patients treated with dabigatran.

关键词： Atrial fibrillation Bleeding Body mass index Dabigatran

Water-ultrastable perovskite CsPbBr_(3)nanocrystals for fluorescence-enhanced cellular imaging

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Rare Metals 2023年第5期42卷 1624-1634页

作者： Cai-Li He Zi-Qi Meng Shu-Xia Ren Jian Li Ye Wang Hao Wu Hui Bu yu Zhang wei-Zhong Hao Shu-Lin Chen rong-rong Yan Huan Liu yu-Fang Zhu Jin-Jin Zhao Department of Neurology The Second Hospital of Hebei Medical UniversityShijiazhuang050000China Institute of Materials for Energy Conversion School of Materials Science and EngineeringShijiazhuang Tiedao UniversityShijiazhuang050043China General Practice Department Liaocheng City People’s HospitalLiaocheng252000China Tianjin Key Laboratory of Retinal Functions and Diseases Tianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin300000China General Practice Department Hengshui People’s HospitalHengshui053000China The 984th Hospital of the PLA Integrated TCM&Western Medicine Department Beijing100094China KAUST Catalysis Center(KCC) Division of Physical Sciences and EngineeringKing Abdullah University of Science and Technology(KAUST)Thuwal23955-6900Saudi Arabia State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Hebei Key Laboratory of Inorganic Nano-materials College of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang050024China

Metal halide perovskites have attracted much attention in biomedicine because of their excellent fluorescence energy conversion properties;however,poor water-stability and cytotoxicity limit its applications as a biomedical tracer,especially in cellular ***,water-ultrastable perovskites C sPbBr_(3):Cs_(4)PbBr_(6)nanocrystals(NCs)encapsulated in chitosan are fabricated successfully using a water-triggered *** as-synthesized CsPbBr_(3):Cs_(4)PbBr_(6)@CS(chitosan,CS)nanoparticles in water display enhanced fluorescence emission for 35 ***,the viability of glioma cells(U87 cells)incubated with different concentrations of CsPbBr_(3):Cs_(4)PbBr_(6)@CS nanoparticles(0-20μg·ml^(-1))for24 h is found to be higher than 90%.In artificial body fluid,analyses using laser confocal microscopy,the standard Cell Counting Kit-8(CCK-8)method,and flow cytometry demonstrated the good water ultrastability and high biocompatibility performance of CsPbBr_(3):Cs_(4)PbBr_(6)@CS nanoparticles in cellular ***,the water-ultrastable halide perovskites support promising perspectives in biological cell tracing and intelligent medical technology.

关键词： Perovskites nanocrystals Chitosan Waterultrastable High biocompatibility Cellular imaging

双环境力耦合作用下小口径弹药引信火工品装药的力学响应

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火工品 2024年第2期 41-45页

作者：王光宇王雨时陈建宇王嘉伟罗定南京理工大学机械工程学院江苏南京210094 重庆望江工业有限公司重庆400071

为探究轴向过载和由高转速引起的离心过载耦合作用下小口径弹药引信火工品装药的力学响应,采用ANSYS软件对实际发射情况和简化情况下药剂最大等效应力和最大静水压力的变化进行了数值模拟研究。结果表明,采用静态等效方法分析时,离心过... 详细信息

为探究轴向过载和由高转速引起的离心过载耦合作用下小口径弹药引信火工品装药的力学响应,采用ANSYS软件对实际发射情况和简化情况下药剂最大等效应力和最大静水压力的变化进行了数值模拟研究。结果表明,采用静态等效方法分析时,离心过载对药剂最大等效应力影响很小,基本可以忽略不计,但其对最大静水压力有一定影响;当药剂处于弹性变形阶段时,其最大等效应力基本由最大轴向过载决定,而由高转速产生的离心过载和轴向过载曲线周期对最大等效应力的影响很小;最大等效应力、最大静水压力均与最大轴向过载呈明显的线性关系。

关键词：引信火工品小口径弹药力学响应数值模拟轴向过载离心过载

A review on WO_(3)-based composite photocatalysts:synthesis,catalytic mechanism and diversified applications

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Rare Metals 2024年第8期43卷 3441-3459页

作者： Xue Zhang Zi-Qi Zhang Yan-Dong Sun Xiao-Jia Ma Feng-Xian Jin Fang-yuan Zhang wei-Guang Han Bo-Xiong Shen Sheng-Qi Guo College of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300401China Department of Food and Chemical Engineering Liuzhou Institute of TechnologyLiuzhou 545616China

Photocatalysis as an emerging "green" energy conversion technology has attracted domestic and international *** technology uses semiconductor photocatalysts to convert solar energy into directly usable chemical energy,showing great potential for application in environmental pollutant purification and clean energy production,with broad development *** many semiconductor materials,tungsten trioxide(WO_(3)) is favored by researchers in the field of photocatalysis because of its good visible light response and excellent valence band hole oxidation ***,a large number of photocatalysts based on WO_(3),in particular W03-based composite photocatalysts,have been reported,and their applications cover a wide range of *** order to promote the development of WO_(3)-based photocatalysts and provide a reference for colleagues,we present a systematic summary of the applications and research progress of W03-based composites in the field of photocatalysis in recent *** from the structural properties of WO_(3)itself,this article summarizes the preparation methods and structure-activity relationships of WO_(3)-based composite ***,it introduces the current application status of existing WO_(3)-based composite photocatalysts in CO_(2) reduction,hydrogen production,nitrogen fixation,and pollutant ***,the development prospects were analyzed.

关键词： WO_(3)-based composite photocatalysts Intrinsic characteristic Preparation method Reaction mechanism Applications

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再生水利用配置的基本要素与理论模型研究

自然资源学报 2024年第6期39卷 1450-1472页

作者：韩宇飞吴凤平王维季英雯王瑞方王晓宇河海大学商学院南京211100 河海大学商学院规划与决策研究所南京211100

再生水利用配置是推动再生水高效利用的重要手段。针对中国再生水配置理论的欠缺,在总结美国、日本、新加坡、以色列等典型国家再生水利用配置主要经验的基础上,提出中国再生水利用配置的三个基本要素:再生水价格机制、再生水供需状况... 详细信息

再生水利用配置是推动再生水高效利用的重要手段。针对中国再生水配置理论的欠缺,在总结美国、日本、新加坡、以色列等典型国家再生水利用配置主要经验的基础上,提出中国再生水利用配置的三个基本要素:再生水价格机制、再生水供需状况以及再生水配置关系;针对核心要素,构建再生水利用配置的理论模型:一是基于再生水利用成本、供需双方再生水影子价格构建再生水综合价格模型,二是基于再生水需求主体、再生水需求驱动因素构建再生水需求总量预测模型,三是基于“自上而下”的目标要求建立再生水利用配置的区间双层规划模型,以实现“地区—行业”不同层级的再生水配置。本研究旨在完善再生水利用配置理论,为推动污水资源化利用提供决策参考。

关键词：再生水利用配置再生水价格再生水供需状况再生水配置关系区间双层规划模型

忆阻Morris-Lecar神经网络的同步行为研究

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广西师范大学学报（自然科学版） 2024年第1期42卷 67-78页

作者：黄微韦笃取广西师范大学电子与信息工程学院广西桂林541004

本文研究电磁感应系数和膜表面电荷尺寸对忆阻Morris-Lecar(ML)神经网络动力学行为的影响。以电荷尺寸为参数研究忆阻ML神经网络的放电行为,发现增大电荷尺寸会抑制神经元放电频率和幅度,神经元随着时间的推移进入静息状态。以电磁感应... 详细信息

本文研究电磁感应系数和膜表面电荷尺寸对忆阻Morris-Lecar(ML)神经网络动力学行为的影响。以电荷尺寸为参数研究忆阻ML神经网络的放电行为,发现增大电荷尺寸会抑制神经元放电频率和幅度,神经元随着时间的推移进入静息状态。以电磁感应系数和电荷尺寸作为变量研究神经网络的同步行为。固定电荷尺寸,增大电磁感应系数,神经网络由混沌变得有序;电磁感应系数是决定神经网络同步的关键因素,当电磁感应系数K>3.2时,能更有效地诱导和增强同步。引入同步因子和标准差分别对网络的同步程度和神经元放电程度进行量化。实验结果表明,电磁感应系数可以有效调节神经网络的同步行为,具有控制神经网络的放电模式和网络同步的作用。

关键词： Morris-Lecar 神经元电磁感应表面电荷同步放电