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Decision Support System for Adaptive Restoration Control of Transmission System

Journal of Modern Power Systems and Clean Energy 2021年第4期9卷 870-885页

作者： ze li Yusheng Xue Haohao Wang lili Hao School of Electrical Engineering Southeast UniversityNanjingChina State Grid Electric Power Research Institute(NARI Group Corporation) NanjingChina State Grid Electric Power Research Institute(NARI Group Corporation) NanjingChinaand they are also with State Key Laboratory of Smart Grid Protection and Operation ControlNanjingChina School of Electrical Engineering and Control Science Nanjing Tech UniversityNanjingChina

The power system restoration control has a higher uncertainty level than the preventive control of cascading failures. In order to ensure the feasibility of the decision support system of restoration control, a decision support framework for adaptive restoration control of transmission system is proposed, which can support the coordinated restoration of multiple partitions, coordinated restoration of units and loads, and coordination of multi-partition decision-making process and actual restoration process. The proposed framework is divided into two layers, global coordination layer and partition optimization layer. The upper layer partitions the transmission system according to the power outage scenario, constantly and dynamically adjusts the partitions during the restoration process, and optimizes the time-space decision-making of inter-partition connectivity. For each partition, the lower layer pre-selects restoration targets according to the estimated restoration income, optimizes the corresponding restoration paths, and evaluates the restoration plans according to the expected net income per unit of power consumption. During the restoration process, if the restoration operation such as energizing the outage branch fails, the current restoration plan will be adaptively switched to the sub-optimal one or re-optimized if necessary. The framework includes two operation modes, i.e., the on-line operation mode and training simulation mode, and provides an information interaction interface for collaborative restoration with related distribution systems. The effectiveness and adaptability of the proposed framework is demonstrated by simulations using the modified IEEE 118-bus system.

关键词： Transmission system restoration two-layer decision support framework restoration risk and income restoration uncertainty sand table deduction

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呋虫胺和唑虫酰胺在茶叶加工过程中的残留特征及膳食风险评估

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食品科学 2025年第1期46卷 192-199页

作者：李春勇吕莹金静王霞秦曙山西农业大学山西功能农产品检验检测中心山西太原030031

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后... 详细信息

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后,经超高效液相色谱-串联质谱法检测,外标法定量。结果表明:在0.005~0.500μg/mL范围内,呋虫胺及其代谢物、唑虫酰胺质量浓度与其响应峰面积呈良好线性关系(R^(2)>0.99),在0.05、1.00、20.00、50.00 mg/kg(茶鲜叶、茶干叶),0.05、0.10、5.00 mg/kg(茶汤)添加水平下,呋虫胺及其代谢物1-甲基-3-[(3-四氢呋喃)甲基]脲、1-甲基-3-[(3-四氢呋喃)甲基]二氢胍盐的平均加标回收率为74%~103%,相对标准偏差为1%~9%;唑虫酰胺的平均加标回收率为75%~95%,相对标准偏差为1%~6%,方法定量限均为0.05 mg/kg;20%呋虫胺·唑虫酰胺微乳剂按推荐剂量施药后,呋虫胺(含代谢物)在茶鲜叶中的规范残留试验中值(supervised trials median residue,STMR)经烘干因子校正后与茶干叶中STMR相应的国家估算每日摄入量(national estimated daily intake,NEDI)均为4.08 mg,占每日允许摄入量(allowable daily intake,ADI)的32.4%;唑虫酰胺在茶鲜叶中的STMR经烘干因子校正后的NEDI为0.17581 mg,占ADI的46.5%,茶干叶中STMR对应的NEDI为0.18925 mg,占ADI的50.1%,呋虫胺和唑虫酰胺在不同评估模型下获得的长期膳食暴露风险均低于100%;呋虫胺(含代谢物)经加工因子校正后的国际短期膳食摄入量(international estimation of short-term dietary intake,IESTI)与校正前处于同一风险水平,低于急性参考剂量(acute reference dose,ARfD)(1 mg/kg);唑虫酰胺的IESTI为3.46×10^(-4) mg/kg(采收间隔7 d),低于ARf D(0.01 mg/kg),本研究方法在茶汤中未检测到唑虫酰胺残留,故未得到浸泡因子及相应的IESTI。综上,按推荐剂量在茶树上使用20%呋虫胺·唑虫酰胺微乳剂是安全的,最终残留量对应的长期及急性膳食摄入风险均在可接受范围,利用加工因子校正评估模型更切合实际风险水平。

关键词：呋虫胺唑虫酰胺茶叶加工因子残留特征风险评估

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Design of A Novel Wheel-Legged Robot with Rim Shape Changeable Wheels

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 62-72页

作者： ze Fu Hao Xu Yinghui li Weizhong Guo State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

The wheel-legged hybrid structure has been utilized by ground mobile platforms in recent years to achieve good mobility on both flat surfaces and rough ***,most of the wheel-legged robots only have one-directional obstacle-crossing *** the motion,most of the wheel-legged robots’centroid fluctuates violently,which damages the stability of the ***’s more,many designs of the obstacle-crossing part and transformation-driving part of this structure are highly coupled,which limits its optimal performance in both *** paper presents a novel wheel-legged robot with a rim-shaped changeable wheel,which has a bi-directional and smooth obstacle-crossing *** on the kinematic model,the geometric parameters of the wheel structure and the design variables of the driving four-bar mechanism are optimized *** kinetostatics model of the mobile platform when climbing stairs is established to determine the body length and angular velocity of the driving wheels.A pro-totype is made according to the optimal *** show that the prototype installed with the novel transformable wheels can overcome steps with a height of 1.52 times of its wheel radius with less fluctuation of its centroid and performs good locomotion capabilities in different environments.

关键词： Mobile platform Transformable wheel-legged robot Kinematics analysis Mechanical design Obstacle

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Reliability analysis of k-out-of-n system with load-sharing and failure propagation effect

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1221-1231页

作者： CHEN Ying MA Qichao WANG ze li Yingyi Science and Technology on Reliability and Environmental Engineering Laboratory Beihang UniversityBeijing 100191China Institute of Electronic Engineering China Academy of Engineering PhysicsMianyang 621999China

In complex systems,functional dependency and physical dependency may have a coupling *** this paper,the reliability of a k-out-of-n system is analyzed considering load-sharing effect and failure mechanism(FM)*** types of FMs are considered and an accumulative damage model is proposed to illustrate the system behavior of the k-out-of-n system and the coupling effect between load-sharing effect and FM propagation effect.A combinational algorithm based on Binary decision diagram(BDD)and Monte-Carlo simulation is presented to evaluate the complex system behavior and reliability of the k-out-of-n system.A current stabilizing system that consists of a 3-out-of-6 subsystem with FM propagation effect is presented as a case to illustrate the complex behavior and to verify the applicability of the proposed *** to the coupling effect change,the main mechanism and failure mode will be changed,and the system lifetime is *** are analyzed and results show that different sensitivity factors of three different FMs lead to the change of the development rate,thus changing the failure *** the coupling effect may lead to an incomplete and ineffective measuring and monitoring *** strategies must be adopted to make the FM propagation insensitive to load-sharing effect.

关键词： k-out-of-n system load-sharing effect failure mechanism propagation damage factor model combinational algorithm

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Inhibition Mechanism of Cholinesterases by Carbamate: A Theoretical Study

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Chemical Research in Chinese Universities 2008年第6期24卷 778-781页

作者： YAO Yuan li ze-sheng State Key Laboratory of Theoretical and Computational Chemistry institute of Theoretical Chemistry Jilin University Changchun 130021 P R. China

The density functional theory at the B3LYP/6-311G（d, p） level was applied to exploring the inhibition mechanism of cholinesterases by carbamate. The results indicate that the inhibition reactions with or without the catalytic effect of the catalytic triad in eholinesterases underwent a two-step addition-elimination mechanism, which is in good agreement with the proposed mechanism. The solvent has a strong effect on the inhibition reactions and the reaction with the catalytic triad in the solvent phase is close to the real reaction under biological condition.

关键词： Carbamate Cholinesterase Inhibition mechanism Solvent effect

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Vertex partitions of r-edge-colored graphs

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Applied Mathematics(A Journal of Chinese Universities) 2008年第1期23卷 120-126页

作者： JIN ze-min li Xue-liang Center for Combinatorics and LPMC-TJKLC Nankai University Tianjin 300071 China. Department of Mathematics Zhejiang Normal University Jinhua 321004 China.

Let G be an edge-colored graph. The monochromatic tree partition problem is to find the minimum number of vertex disjoint monochromatic trees to cover the all vertices of G. In the authors＇ previous work, it has been proved that the problem is NP-complete and there does not exist any constant factor approximation algorithm for it unless P= NP. In this paper the authors show that for any fixed integer r ≥ 5, if the edges of a graph G are colored by r colors, called an r-edge-colored graph, the problem remains NP-complete. Similar result holds for the monochromatic path （cycle） partition problem. Therefore, to find some classes of interesting graphs for which the problem can be solved in polynomial time seems interesting. A linear time algorithm for the monochromatic path partition problem for edge-colored trees is given.

关键词： monochromatic tree (path cycle) NP-complete linear time algorithm.

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Interactional models for adults of two populations with maturation delays

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Applied Mathematics(A Journal of Chinese Universities) 2008年第2期23卷 127-135页

作者： HE ze-rong li Jian-quan Institute of Operational Research and Cybernetics Hangzhou Dianzi University Hangzhou 310018China Department of Applied Mathematics and Physics Air Force Engineering University Xi＇an 710051China

This paper is concerned with interactional models for adults of two species delayed by their mature periods. The existence and local stability of equilibria are discussed thoroughly for competitive systems, cooperative systems and predator-prey systems, respectively. For systems with interaction of competition and cooperation, it is found that the two populations are uniformly persistent if the positive equilibrium is stable. For predator-prey interaction, however, some further conditions are needed to guarantee the persistence of the systems.

关键词： interactional models, mature period, equilibrium stability, uniform persistence.

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Study on performance degradation and failure analysis of machine gun barrel

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Defence Technology（防务技术） 2020年第2期16卷 362-373页

作者： Xiaolong li Lei Mu Yong Zang qin qin School of Mechanical Engineering University of Science and Technology BeijingBeijing100083China

An increase in the use of the gun barrel will cause wear of the inner wall,which reduces the muzzle velocity and the spin rate of the *** off-bore flight attitude and trajectory of the projectile also change,affecting the shooting power and the *** ballistic data of a high-speed spinning projectile are required to study the performance ***,based on the barrel’s accelerated life test,the whole process of projectile shooting is reproduced using numerical simulation technology,and key information on the ballistic performance change at each shooting stage are *** have shown that in the later stages of barrel shooting,the accuracy of shooting has not decreased ***,it is found that the angle of attack of the projectile increases as the wear of the barrel *** maximum angle of attack reaches 0.106 rad when the number of shots reaches ***,elliptical bullet hole has appeared on the target at this shooting *** combining external ballistic theory with simulation results,the primary reason of this phenomenon is found to be a significant decrease in the muzzle spin rate of the *** the end of the barrel life,the projectile muzzle spin rate is 57.5%lower than that of a barrel without wear.

关键词： Wear of the inner wall Accelerated life test Numerical simulation Ballistic performance End of the barrel life

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Accelerate Bose–Einstein condensate by interaction

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Chinese Physics B 2019年第12期28卷 286-291页

作者： Jie-li qin School of Physics and Electronic Engineering Guangzhou UniversityGuangzhou 510006China

In recent years,accelerating waves have attracted great research interests both due to their unique properties and tempting *** we investigate the effect of the inter-particle interaction on accelerating of Bose–Einstein condensate(BEC).We show that spatially homogeneous interactions will have no accelerating effect on BEC regardless of the interaction form(contact,dipole–dipole,or any others).But spatially inhomogeneous interactions may lead to an accelerating motion of the *** an example,the accelerating dynamic of BEC under a spatially linear modulated contact interaction is studied in *** is found that such an interaction will accelerate the condensate with a time varying ***,an interaction engineering scheme to achieve constantly accelerating BEC is proposed and studied *** results suggest that this engineering scheme can also suppress profile changing of the condensate during its evolution,thus realize an accelerating profile-keeping matter wave *** analysis also applies to optical waves with Kerr nonlinearity.

关键词： Bose–Einstein condensate interaction acceleration

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On Mbius Form and Mbius Isoparametric Hypersurfaces

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2077-2092页

作者： ze Jun HU Xiao li TIAN Department of Mathematics Zhengzhou University Zhengzhou 450052 P. R. China Department of Humanities and Social Sciences He 'nan Vocational and Technical College of Communications Zhengzhou 450007 P. R. China

An umbilic-free hypersurface in the unit sphere is called MSbius isoparametric if it satisfies two conditions, namely, it has vanishing MSbius form and has constant MSbius principal curvatures. In this paper, under the condition of having constant MSbius principal curvatures, we show that the hypersurface is of vanishing MSbius form if and only if its MSbius form is parallel with respect to the Levi-Civita connection of its MSbius metric. Moreover, typical examples are constructed to show that the condition of having constant MSbius principal curvatures and that of having vanishing MSbius form are independent of each other.

关键词： Mobius isoparametric hypersurface Mobius second fundamental form Mobius metric MSbius form paxallel Mobius form

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