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地面颤振模拟试验临界颤振速度关键影响因素分析

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航天器环境工程 2025年第01期42卷 58-65页

作者：高博孙健张忠杨执钧郭静北京强度环境研究所可靠性与环境工程技术重点实验室北京宇航系统工程研究所

为提高飞行器地面颤振模拟试验的有效性，文章分析了影响地面颤振模拟试验结果（即临界颤振速度）的关键因素，并提出关于试验实施的指导性意见。首先通过对试验流程的分析梳理出可能影响试验结果的6大因素；然后分别建立了地面颤振模... 详细信息

为提高飞行器地面颤振模拟试验的有效性，文章分析了影响地面颤振模拟试验结果（即临界颤振速度）的关键因素，并提出关于试验实施的指导性意见。首先通过对试验流程的分析梳理出可能影响试验结果的6大因素；然后分别建立了地面颤振模拟试验系统的“原理模型”、“理想化模型”和“详细模型”三个时域仿真模型，并利用仿真模型系统分析各因素对临界颤振速度的影响。结果表明：硬件设备的时钟频率会影响临界颤振速度，时钟频率取值为1000 Hz较为合适；加载系统的相位延迟对结果的影响较大，试验中必须保证加载控制算法具有足够高的相位追踪精度。该研究旨在为飞行器设计师提供更精确的颤振评估试验技术手段。

关键词：气动弹性分析数值模拟地面颤振模拟试验仿真模型系统时滞

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配网不停电作业工程电缆漏电预警技术

自动化技术与应用 2025年第2期44卷 132-135页

作者：杨东宁孙建史建云云南电网有限责任公司信息中心云南昆明650000 南方电网深圳数字电网研究院有限公司广东深圳518000

针对目前方法存在漏电故障检测时间长、预警性能差的问题,提出配网不停电作业工程电缆漏电预警技术。该方法首先提取电缆漏电故障传播特性并对漏电位置信号进行模态分解获取电缆故障分布情况;再对漏电故障的严重度指标进行获取,建立漏... 详细信息

针对目前方法存在漏电故障检测时间长、预警性能差的问题,提出配网不停电作业工程电缆漏电预警技术。该方法首先提取电缆漏电故障传播特性并对漏电位置信号进行模态分解获取电缆故障分布情况;再对漏电故障的严重度指标进行获取,建立漏电严重程度等级;最后通过评价向量确定漏电的严重程度等级,完成电缆漏电预警。实验结果表明,运用该方法进行漏电预警时,能够有效测试出漏电严重等级,漏电故障检测时间短、预警性能好。

关键词：配电网不停电作业电缆漏电预警方法故障检测

On the Structure of Graded λ-Hopf Algebras

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Acta Mathematica Sinica,English Series 2009年第1期25卷 95-108页

作者： jian Hua sun Pu ZHANG Department of Mathematics Yangzhou University Yangzhou 225002 P. R. China Department of Mathematics Shanghai Jiaotong University Shanghai 200000 P. R. China

Let G be an abelian group, B the G-graded λ-Hopf algebra with A being a bicharacter on G. By introducing some new twisted algebras （coalgebras）, we investigate the basic properties of the graded antipode and the structure for B. We also prove that a G-graded λ-Hopf algebra can be embedded in a usual Hopf algebra. As an application, it is given that if G is a finite abelian group then the graded antipode of a finite dimensional G-graded A-Hopf algebra is invertible.

关键词： twisted algebra (coalgebra) graded Hopf algebra graded antipode

On the Predator-Prey System with Holling-(n+1)Functional Response

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Acta Mathematica Sinica,English Series 2007年第1期23卷 1-6页

作者： Wei WANG jian Hua sun Department of Mathematics Nanjing University Nanying 210008 P. R. China

The qualitative properties of a predatorprey system with Holling-（n ＋ 1） functional response and a fairly general growth rate are completely investigated. The necessary and sufficient condition to guarantee the uni... 详细信息

关键词： Predator-prey system Limit cycle Uniqueness Dulac function

On Positioning and Selection of Mediation and Judgment

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学术界 2014年第10期 273-278页

作者： sun jian Law School Nanjing Normal University Nanjing' Jiangsu 210046

The relationship between mediation and the judgment directly affect the practical effects of judicial power operation,and have important influence on judicial practice. Mediation and judgment have been contradicting each other for a long time,which is the result of the social situation,national policies and other factors intertwined. Practically the alienation of the relationship between mediation and judgment,such as phenomenon of attaching more importance to mediation and less importance to judgment,arbitrary application of mediation,as well as failure to give full play to the due function of mediation and judgment,have deep social reasons,and lead to certain degree of harm. Both mediation and judgment are important means to effectively resolve disputes,with functional complementation of mediation and judgment. Meanwhile judgment serves as an important guarantee for mediation to function. Therefore,to realize scientific selection based on combination of mediation and judgment,it must adhere to classification management over applicable scope of mediation and judgment,application conditions of mediation and judgment,timing of applying mediation and judgment,and supporting mechanismfor scientific selection of mediation and judgment.

关键词：调解判决定位科学选择应用程序功能互补分类管理支持机制

Vehicle actuation based short-term traffic flow prediction model for signalized intersections

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Journal of Central South University 2012年第1期19卷 287-298页

作者： sun jian ZHANG Lun Transportation Research Center School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Transportation Engineering Tongji UniversityShanghai 201804China

Traffic flow prediction is an important component for real-time traffic-adaptive signal control in urban arterial *** exploring available detector and signal controller information from neighboring intersections,a dynamic data-driven flow prediction model was *** model consists of two prediction components based on the signal states(red or green) for each movement at an upstream *** characteristics of each signal state were carefully examined and the corresponding travel time from the upstream intersection to the approach in question at the downstream intersection was *** an online turning proportion estimation method,along with the predicted travel times,the anticipated vehicle arrivals can be forecasted at the downstream *** model performance was tested at a set of two signalized intersections located in the city of Gainesville,Florida,USA,using the CORSIM microscopic simulation *** results show that the model agrees well with empirical arrival data measured at 10 s intervals within an acceptable range of 10%-20%,and show a normal *** is reasonably believed that the model has potential applicability for use in truly proactive real-time traffic adaptive signal control systems.

关键词： adaptive signal control least-squared estimation microscopic simulation travel flow prediction urban arterials

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8种多酚与花生球蛋白相互作用的研究

食品工业科技 2025年第2期46卷 74-82页

作者：张祖薇李如蕊杨聪孟永艳沈明娟孙健张雪春西南林业大学生物与食品工程学院云南昆明650224

为探究花生球蛋白与8种常见多酚的相互作用,包括阿魏酸、白藜芦醇、橙皮素、儿茶素、槲皮素、姜黄素、没食子酸和杨梅素。采用紫外-可见光谱、荧光光谱分析8种多酚与花生球蛋白的相互作用规律,并探讨多酚对蛋白质结构、表面疏水性及溶... 详细信息

为探究花生球蛋白与8种常见多酚的相互作用,包括阿魏酸、白藜芦醇、橙皮素、儿茶素、槲皮素、姜黄素、没食子酸和杨梅素。采用紫外-可见光谱、荧光光谱分析8种多酚与花生球蛋白的相互作用规律,并探讨多酚对蛋白质结构、表面疏水性及溶解度的影响。紫外-可见光谱分析显示,8种多酚改变了花生球蛋白的氨基酸残基所处的微环境,使其分子构象发生改变;荧光光谱表明,多酚对花生球蛋白的猝灭机制均为静态猝灭;其中白藜芦醇和儿茶素与花生球蛋白结合率最高。聚丙烯酰胺凝胶电泳显示,儿茶素、杨梅素、没食子酸与花生球蛋白通过共价交联形成了大分子量的聚合物;傅里叶红外光谱表明,多酚使花生球蛋白的构象发生不同程度改变,其中大部分多酚使花生球蛋白的α-螺旋占比增大,最高增加到36.33%。多酚使花生球蛋白表面疏水性和溶解度均下降,最低分别降至19.92μg和51.7%。综上,8种多酚与花生球蛋白相互作用,不同程度地改变了花生球蛋白的构象和理化性质。该研究可为多酚与花生球蛋白的进一步加工利用提供科学依据及理论指导。

关键词：花生球蛋白多酚相互作用光谱结构

维普期刊数据库博看期刊

Mechanism of Mg2+ dissolution from olivine and serpentine: Implication for bioleaching of high-magnesium nickel sulfide ore at elevated pH

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International Journal of Minerals,Metallurgy and Materials 2019年第9期26卷 1069-1079页

作者： jian-zhi sun jian-kang Wen Bo-wei Chen Biao Wu National Engineering Laboratory of Biohydrometallurgy GRINM Group Corporation Limited

To inhibit the dissolution of Mg^2+ during the bioleaching process of high-magnesium nickel sulfide ore, the effect of major bioleaching factors on the dissolution of Mg^2+ from olivine and serpentine was investigated and kinetics studies were carried out. The results indicated that the dissolution rate-controlling steps are chemical reaction for olivine and internal diffusion for serpentine. The most influential factor on the dissolution of Mg^2+ from olivine and serpentine was temperature, followed by p H and particle size. A novel method of bioleaching at elevated pH was used in the bioleaching of Jinchuan ore. The results showed that elevated pH could significantly reduce the dissolution of Mg^2+ and acid consumption along with slightly influencing the leaching efficiencies of nickel and cobalt. A model was used to explain the leaching behaviors of high-magnesium nickel sulfide ore in different bioleaching systems. The model suggested that olivine will be depleted eventually, whereas serpentine will remain because of the difference in the rate-controlling steps. Bioleaching at elevated pH is a suitable method for treating high-magnesium nickel sulfide ores.

关键词： olivine serpentine high-magnesium nickel sulfide ore bioleaching shrinking core model elevated pH

Analysis of Stealthy False Data Injection Attacks Against Networked Control Systems:Three Case Studies

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Journal of Systems Science & Complexity 2023年第4期36卷 1407-1422页

作者： PANG Zhonghua FU Yuan GUO Haibin sun jian Key Laboratory of Fieldbus Technology and Automation of Beijing North China University of TechnologyBeijing 100144China National Key Laboratory of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

This paper mainly investigates the security problem of a networked control system based on a Kalman filter.A false data injection attack scheme is proposed to only tamper the measurement output,and its stealthiness and effects on system performance are analyzed under three cases of system knowledge held by an attacker and a ***,it is derived that the proposed attack scheme is stealthy for a residual-based detector when the attacker and the defender hold the same accurate system ***,it is proven that the proposed attack scheme is still stealthy even if the defender actively modifies the Kalman filter gain so as to make it different from that of the ***,the stealthiness condition of the proposed attack scheme based on an inaccurate model is ***,for each case,the instability conditions of the closed-loop system under attack are ***,simulation results are provided to test the proposed attack scheme.

关键词： False data injection attack networked control systems(NCSs) stability stealthiness