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Acta Mechanica Sinica 2017年第1期33卷 200-207页

作者： shu sun shu-Qian Cao Department of Mechanics School of Mechanical Engineering Tianjin University Tianjin 300350 China College of Science North China University of Science and Technology Tangshan 063009 China Tianjin Key Laboratory of Nonlinear Dynamics and Chaos Control Tianjin 300350 China

By applying the second order Melnikov function, the chaos behaviors of a bistable piezoelectric cantilever power generation system are analyzed. Firstly, the conditions for emerging chaos of the system are derived by the second order Melnikov function. Secondly, the effects of each item in chaos threshold expression are analyzed. The excitation frequency and resistance values, which have the most influence on chaos threshold value, are found. The result from the second order Melnikov function is more accurate compared with that from the first order Melnikov function. Finally, the attraction basins of large amplitude motions under different exciting frequency, exciting amplitude, and resistance parameters are given.

关键词： Bistable piezoelectric cantilever beam Second order Melnikov function Homoclinic bifurcation Basin of attraction

Distributed Reduced-order Optimal Fusion Kalman Filters for Stochastic Singular Systems

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自动化学报 2006年第2期32卷 286-290页

作者： sun shu-Li MA Jing Department of Automation Heilongjiang University Harbin 150080

Based on the optimal fusion algorithm weighted by matrices in the linear minimum variance (LMV) sense, a distributed full-order optimal fusion Kalman filter (DFFKF) is given for discrete-time stochastic singular systems with multiple sensors, which involves the inverse of a high-dimension matrix to compute matrix weights. To reduce the computational burden, a distributed reduced-order fusion Kalman filter (DRFKF) is presented, which involves in parallel the inverses of two relatively low-dimension matrices to compute matrix weights. A simulation example shows the effectiveness.

关键词：多传感器信息融合 Kalman滤波随机奇异系统

Flow response hysteresis of throat regulation process of a two-dimensional mixed-compression supersonic inlet

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Chinese Journal of Aeronautics 2022年第3期35卷 112-127页

作者： Yi JIN shu sun Huijun TAN Yue ZHANG Hexia HUANG Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

The variable geometry supersonic inlet tends to decrease the throat area to reduce the Mach number upstream of the terminal shock,so as to reduce the flow ***,excessive Internal Contraction Ratio(ICR)exposes the inlet to a greater risk of unstart,which inevitably results in a process of increasing the throat area to aid the inlet *** the above throat regulation process,the inlet undergoes the start,unstart,and restart states in *** order to reveal the flow structure and mechanism of this process,a two-dimensional unsteady numerical simulation combined with a dynamic mesh technique were *** shock-on-lip Mach number of the studied inlet is 4.0 and the flight angle of attack is+6°.Analysis was focused on the state with a freestream Mach number of *** results clearly show that the flow response hysteresis appears,and restart is only realized when the throat area is obviously increased as compared to that of unstart due to the historical unstart flow *** addition,three typical flow fields were analyzed,and it is found that the separation ahead of the inlet was the key factor affecting the ***,unstart and restart boundaries of the inlet were discussed,and the factors influencing its deviation from the typical boundaries of dual-solution area were *** newly predicted unstart and restart boundaries are much closer to the CFD results.

关键词： Hysteresis Restart Supersonic inlet Throat regulation process Unstart Unsteady numerical simulation

Studies on the esterifications of 9-(hydroxyimino)-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one with acid chlorides under different conditions

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Chinese Chemical Letters 2008年第7期19卷 791-794页

作者： Ru shu sun Yang Wang Peng Xia Department of Medicinal Chemistry School of Pharmacy Fudan University Shanghai 200032 China

The esterifications of 9-（hydroxyimino）-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one （4） with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as the acid scavenger, whereas the reactions gave unexpected 8-substituted products N-（8-chloro-4-methyl-2-oxo-2H-furo-[2,3-h]chromen-9-yl）amides （5a-c） and 4-methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloates （6d-e） by using excessive acid chlorides. The structures of 10 new compounds were determined by 1H NMR, 13C NMR, MS and HRMS, and the possible mechanism for the formation of unexpected products 5a--c and 6d-e was also proposed.

关键词： 9-(Hydroxyirnino)-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one Oxime-ester N-(8-Chloro-4-methyl-2-oxo-2H-furo[2,3-h]chro-men-9-yl)amide 4-Methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloate

Identifying glyphosate-tolerant maize by soaking seeds in glyphosate solution

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Journal of Integrative Agriculture 2018年第10期17卷 2302-2309页

作者： YAN shu-feng Sher Muhammad LIU Hai-fang TIE shuang-gui sun shu-ku Cereal Crops Research Institute Henan Academy of Agricultural Sciences Zhengzhou 450002 P.R.China Jamil-ur-Rahman Center for Genome Research International Center for Chemical and Biological Sciences University of Karachi Karachi 75270 Pakistan Institute of Paulownia Henan Agricultural University Zhengzhou 450002 P.R. China Qiqihar Fuer Agronomy Incorporation Qiqihar 161041 P.R. China

The identification of glyphosate-tolerant maize genotypes by field spraying with glyphosate is time-consuming, costly and requires treatment of a large area. We report a potentially better technique of seed-soaking to identify glyphosate-tolerant maize genotypes. The effects of soaking maize seeds in glyphosate solution under controlled conditions were studied on seed germination rate, seedling morphological indices, seedling growth and leaf chlorophyll content. These responses were compared among a glyphosate-tolerant transgenic maize cultivar CC-2, glyphosate-susceptible inbred line Zheng 58（the recurrent parent of CC-2） and hybrid cultivar Zhengdan 1002. The results showed that the germination rate, seedling morphological indices and leaf chlorophyll content of glyphosate-tolerant CC-2 seeds did not change significantly among five different concentrations of glyphosate treatment（0 to 2%）. In contrast, germination rates, seedling morphological indices and leaf chlorophyll contents of Zheng 58 and Zhengdan 1002 seeds were significantly negatively affected by exposure to increasing concentrations of glyphosate. The glyphosate-tolerant inbred line CC-2 displayed a strong tolerance to glyphosate after soaking in 0.1 to 2.0% glyphosate solutions, while both the inbred line Zheng 58 and hybrid Zhengdan 1002 were susceptible to glyphosate. The accuracy of the glyphosate-soaking method for screening glyphosate-tolerant maize was confirmed using a field spraying trial.

关键词： EPSPS glyphosate leaf chlorophyll content maize seed-soaking

Simulation and reliability analysis of shunt active power filter based on instantaneous reactive power theory

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 416-421页

作者： CUI Yu-long LIU Hong WANG Jing-qin sun shu-guang School of Information Science ＆ Technology. Beijing University of Chemical Technology Beijing 100029 China School of Electrical Engineering Hebei University of Technology Tianjin 300130 China

This paper first discusses the operating principle of instantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink power system toolbox is used to simulate the system. In the simulation model, as the most common harmonic source, 3-phase thyristor bridge rectifier circuit is constructed. The simulation results before and after the shunt active filter was switched to the system corresponding to different firing angles of the thyristors are presented and analyzed, which demonstrate the practicability and reliability of the proposed shunt active filter scheme.

关键词： shunt active filter Instantaneous reactive power theory Harmonic 3-phase thyristor bridge rectifier Matlab/ Simulink

Experimental investigation on unstart-restart hysteresis of a supersonic inlet during throat regulation

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Chinese Journal of Aeronautics 2023年第11期36卷 135-152页

作者： Yi JIN Huijun TAN Hao ZHANG Gaojie ZHENG shu sun Yue ZHANG Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China Aerospace Times Feipeng Company Limited China Academy of Aerospace Electronics TechnologyKunshan 215000China

The hysteresis during the throat regulation process of a supersonic variable inlet is unconducive to ***,detailed experimental studies of such a hysteresis and its control are necessary.A throat variable supersonic inlet was designed at a shock-on-lip Mach number of 4.0 and an Internal Contraction Ratio(ICR)ranging over 1.21–***,a distributed bleed system was proposed to suppress the *** wind tunnel tests were conducted at Mach number *** throat regulation processes were recorded using a high-speed schlieren and dynamic pressure acquisition *** results indicate that the unstart and restart ICRs during the uncontrolled inlet’s throat regulation process were 1.95 and 1.48,respectively,demonstrating an unstart-restart *** typical flowfields were summarized during the uncontrolled inlet’s restart *** proposed bleed control increased the unstart and restart ICRs to 2.06 and 1.75,respectively,and the inlet realized the designed state as the ICR was further decreased to *** controlled inlet’s hysteresis loop was decreased compared to the uncontrolled ***,the mechanism of the hysteresis,dominated by the entrance separation-induced wave system,was *** mechanisms of the bleed control to broaden the unstart and restart boundaries and suppress the hysteresis were elucidated.

关键词： Supersonic inlet Unstart-restart hysteresis Bleed control Throat regulation process Wind tunnel test

BOUNDEDNESS OF COMMUTATORS OF GENERALIZED FRACTIONAL INTEGRAL OPERATORS ON WEIGHTED HERZ-TYPE HARDY SPACES

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Analysis in Theory and Applications 2010年第2期26卷 101-109页

作者： Aiwen sun Lisheng shu Anhui Normal University China

In this paper, we study the boundedness of higher order commutators of gen- eralized fractional integral operators on weighted Lp spaces and Herz-type Hardy spaces.

关键词： generalized fractional integral commutator weighted Herz-type Hardy space atom

Rb-Sr chronological characteristics of Jurassic granitoid gravels in north margin of Dabie block,Central China

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Chinese Science Bulletin 2001年第13期46卷 1126-1129页

作者： Li Zhong Li Renwei sun shu Zhang Wenhua Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Granitoid gravels are discovered from alluvial fan conglomerates, the base of Jurassic Fenghuangtai Formation (J22), in the north margin of Dabie block and the south part of the Hefei Basin. These granitoid gravels make up 5%-10% of all gravels by volume percent. For the four components, K-feldspar, biotite, amphibole and whole rock divided from two selected granitoid gravel samples, their Rb-Sr isotopes are measured, which gives two formation ages of granitoids: (428±20) Ma and (430±54) Ma, and means that the Early Paleozoic granitoid intrusive rocks once existed in the Dabie Mountain provenances of Jurassic. The granitoids occur in the tectonic setting of post-collision upliftaccording to lithogeochemical discriminant analysis.

关键词： Dabie block Hefei Basin granitoid gravels Rb-Sr isotope chronology depositional provenance.

Application of the Bayes’ theory to the failure rate evaluation of electrical apparatus

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 501-505页

作者： JIN Shao-hua LU Jian-guo WAN Yan-ping sun shu-guang Department of Mathematics Hebei University of Technology Tianjin 300130 China

The Weibull distribution has been widely used in reliability fields. A mixed Weibull distribution represents a popu- lation that consists of several Weibull subpopulations. In this paper, a new approach which combines the least-squares method with Bayes’ theorem, takes advantage of the parameter estimation for single Weibull distribution is developed to estimate the pa- rameters of each subpopulation. The estimates given by this paper also satisfy the maximum likelihood equation. The estimates of the failure rate of the mixed Weibull population are given. An actual test data is computed by using the proposed method. The Kolmogorov-Smirnov goodness-of-fit test turns out that the proposed method yields more accurate result.

关键词： Bayesian estimation Failure rate Least-squares method Maximum likelihood principle Mixed-Weibull distribution