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Insect Science 2013年第1期20卷 61-68页

作者： Xiao-Yi Zhang Kai Lu Jia-Liang zhou qiang zhou State Key Laboratory of Biological Control and Institute of Entomology Sun Yat-sen University Guangzhou China

Nilaparvata lugens （St^il）（Hemiptera： Geometroidea）, a serious rice pest in many countries of Asia, causes a great loss in rice production every year. RNA interference （RNAi） is a powerful technology for gene fimction study in insects and a potential tool for pest control. As a core component of RNAi pathway, Dicer-2 （Dcr-2） protein determines the production of small interfering RNA （siRNA） and is crucial for the efficiency of RNAi. In this study, the full-length complementary DNA （cDNA） ofN. lugens Dcr-2 （NlDcr-2） was first cloned and analyzed, and then the RNAi experiment was conducted to explore the function ofNlDcr-2 gene. The complete Dcv-2 cDNA ofN. lugens was 4 971 bp in length with an open reading frame （ORF） of 1,656 amino acids. Phylogenetic and protein domain analysis showed that the predicted N1Dcr-2 protein was similar to Tribolium castaneum. In the RNAi experiment, the messenger RNA level of NlDcr-2 was significantly reduced by NlDcr-2 double-stranded RNA （dsRNA）（dsDcr-2）. Fifty-five per cent decrease of N1Dcr-2 was found after 4 days of unremitting feeding. No significant effect was observed on the development ofN. lugens after dsRNA ingestion.

关键词： clone Dicer-2 Nilaparvata lugens RNAi qRT-PCR

Dust collector localization in trouble of moving freight car detection system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第2期14卷 98-106页

作者： Fu-qiang zhou Rong ZOU He GAO School of Instrumentation Science and Optoelectronics Engineering Beihang University

For a long time,trouble detection and maintenance of freight cars have been completed manually by *** realize the transition from manual to computer-based detection and maintenance,we focus on dust collector localization under complex conditions in the trouble of moving freight car detection *** mid-level features which are also named flexible edge arrangement(FEA) features,we first build the edge-based 2D model of the dust collectors,and then match target objects by a weighted Hausdorff distance *** difference is that the constructed weighting function is generated by the FEA features other than specified subjectively,which can truly reflect the most basic property regions of the 3D *** results indicate that the proposed algorithm has better robustness to variable lighting,different viewing angle,and complex texture,and it shows a stronger adaptive *** localization correct rate of the target object is over 90%,which completely meets the need of practical applications.

关键词： Hausdorff distance Weighting function Trouble detection Rail transportation

An Efficient Technique to Reverse Engineer Minterm Protection Based Camouflaged Circuit

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Journal of Computer Science & Technology 2018年第5期33卷 998-1006页

作者： Shan Jiang Ning Xu Xue-Yan Wang qiang zhou Department of Computer Science and Technology Wuhan University of Technology Wuhan 430070 China Department of Computer Science and Technology Tsinghua University Beijing 10084 China

Integrated circuit （IC） camouflaging technique has been applied as a countermeasure against reverse engineering （RE）. However, its effectiveness is threatened by a boolean satisfiability （SAT） based de-camouflaging attack, which is able to restore the camouflaged circuit within only minutes. As a defense to the SAT-based de-camouflaging attack, a brand new camouflaging strategy （called CamoPerturb） has been proposed recently, which perturbs one minterm by changing one gate＇s functionality and then restores the perturbed circuit with a separated camouflaged block, achieving good resistance against the SAT-based attack. In this paper, we analyze the security vulnerabilities of CamoPerturb by illustrating the mechanism of minterm perturbation induced by gate replacement, then propose an attack to restore the changed gate＇s functionality, and recover the camouflaged circuit. The attack algorithm is facilitated by sensitization and implication principles in automatic test pattern generation （ATPG） techniques. Experimental results demonstrate that our method is able to restore the camouflaged circuits with very little time consumption.

关键词： reverse engineering circuit camouflaging sensitization and implication minterm perturbation

Dancing on Ropes-Enantioselective Functionalization of Preformed Four-Membered Carbocycles

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Chinese Journal of Chemistry 2022年第11期40卷 1346-1358,I0002页

作者： Jun Chen qiang zhou Huayi Fang Ping Lu Research Center for Molecular Recognition and Synthesis Department of ChemistryFudan University220 Handan LuShanghai 200433China School of Materials Science and Engineering Tianjin Key Lab for Rare Earth Materials and ApplicationsNankai University38 Tongyan RoadTianjin 300350China

Cyclobutane derivatives have been recognized as useful structural motifs in organic synthesis and drug *** the revival of photochemistry,the enantioselective synthesis of cyclobutane derivatives using[2+2]-cycloadditions has garnered numerous *** the other hand,enantioselec-tive functionalization of preformed four-membered carbocycles is emerging as an important complementary approach to access chiral cyclobutane de-rivatives with versatile structural ***,we summarize recent advances in this field from *** avoid undesired C—C bond cleavage driv-en by strain-releasing,it is crucial to choose compatible methods for enantioselective functionalization and meanwhile preserving intact four-membered ring *** by calculated hydrogenation enthalpies,which are used to evaluate the strain energy of indicated C—C bond,a clear picture of the developed methodologies on functionalization of four-membered carbocycles combining the strain energy and enhanced reactivity is presented.

关键词： Enantioselective functionalization Strained molecules Density functional calculations Strain-releasing C-H activation

Global output feedback control of feedforward nonlinear time-delay systems with unknown growth rate and unknown measurement sensitivity

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Control Theory and Technology 2024年第1期22卷 122-134页

作者： Weiyong Yu Keao Gao Hongbing zhou qiang Liu Academy of Artificial Intelligence Beijing Institute of Petrochemical TechnologyBeijing102617China School of Mathematics and Statistics Nanyang Normal UniversityNanyang473061HenanChina

This paper discusses the problem of global state regulation via output feedback for a class of feedforward nonlinear time-delay systems with unknown measurement sensitivity. Different from previous works, the nonlinear terms are dominated by upper triangular linear unmeasured (delayed) states multiplied by unknown growth rate. The unknown growth rate is composed of an unknown constant, a power function of output, and an input function. Furthermore, due to the measurement uncertainty of the system output, it is more difficult to solve this problem. It is proved that the presented output feedback controller can globally regulate all states of the nonlinear systems using the dynamic gain scaling technique and choosing the appropriate Lyapunov–Krasovskii functionals.

关键词： Adaptive control Dynamic gain controllers Feedforward time-delay systems Measurement sensitivity Output feedback

Zero Extension Problem for the Heat Equation

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Acta Mathematica Sinica,English Series 2022年第11期38卷 1981-1997页

作者： Ge Yang DU qiang XU Shu Lin zhou School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China School of Mathematics and Statistics Lanzhou UniversityLanzhou 730000P.R.China LMAM School of Mathematical SciencesPeking UniversityBeijing 100871P.R.China

In this paper we present a necessary and sufficient condition to guarantee that the zeroextended function of the solution for the heat equation in a smaller cylinder is still the solution of the corresponding extension problem in a larger *** prove the results under the frameworks of classical solutions,strong solutions and weak ***,we generalize these results to uniformly parabolic equations of divergence form.

关键词： Heat equation zero extension initial-boundary value problem

Precipitate Phases in an 11% Cr Ferritic/Martensitic Steel with Tempering and Creep Conditions

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Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 48-57页

作者： Xiao-Ling zhou Yin-Zhong Shen Zhi-qiang Xu School of Mechanical Engineering Shanghai Jiao Tong University

Precipitates in an 11% Cr ferritic/martensitic steel containing Nd with tempering and creep conditions were investigated using transmission electron microscope with energy-dispersive X-ray spectroscopy. The precipitates in the steel with a tempering condition were identified to be Cr-rich M23C6 carbide, Nb-rich/V-rich/Ta–Nb-rich MX carbides, Nbrich MX carbonitride, and Fe-rich M5C2 carbide. Nd-rich carbonitride, which is not known to have been reported previously in steels, was also detected in the steel after tempering. Most of the Nb-rich MX precipitates were dissolved, whereas the amount of Ta-rich MX precipitates was increased significantly in the steel after a creep test at 600 °C at an applied stress of180 MPa for 1,100 h. No Fe2 W Laves phase has been detected in the steel after tempering.（Fe, Cr）2W Laves phase with a relatively large size was observed in the steel after the creep test.

关键词： Precipitate phase High-Cr ferritic/martensitic steel High temperature creep Transmission electron microscope

Ethoxylation of Phenols Catalyzed by Metal-Free Lewis Pairs:Living/Controlled Polymerization in a Slow-lnitiation Mode

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Chinese Journal of Chemistry 2021年第9期39卷 2579-2587页

作者： qiang Zhang Yubo zhou Ye Chen Junpeng Zhao Faculty of Materials Science and Engineering South China University of TechnologyGuangzhouGuangdong 510640China Key Laboratory of Luminescence from Molecular Aggregates of Guangdong Province South China University of TechnologyGuangzhouGuangdong 510640China

Phenols,in stead of con venti onal alcoholic compounds,are used to in itiate ring-openi ng polymerizati on(ROP)of ethyle neoxide and propyle ne oxide in bulk at room temperature in cooperati on with the recently prevaili ng bicompone nt metal-free catalyst comprising an organobase and *** and DFT calculation results both point out that due to the lower nucleophilicity of the initiating(phe no late)species than the propagating(alcoholate)species,chai n initiat ion is distinctly slower tha n propagation and the difference becomes eve n larger as the acidity of the phe nolic in itiator ***,we 11-defi ned polyethers with expected molar mass,low dispersity,and high end-group fidelity are afforded substa ntiating that the ROP is living/c on trolled in spite of the slow *** of product composition indicates that the reaction on alcoholates(i.e.,propagation)is effectively inhib-ited by the unreacted phenols during the initiation step because of the adequately large acidity differenee,which is key to the success of the slow-initiation living/controlled *** acidity difference betwee n phe nol and alcohol also facilitates the fulfill-ment of highly selective phenolysis of epoxides,a"1+1"type addition reaction between phenol and epoxide(in excess)rather than the"1+n"type ROP reaction,by use of a milder organobase and decreased Lewis acid/base ratio.

关键词： Ring-opening polymerization Organocatalysis Lewis bases Ethoxylation Phenol

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*** and Underconsumption

学术界 2018年第7期 210-219页

作者： zhou qiang Prum Michel School of Government Peking University Beijing 100871 School of EILA Paris Diderot University Paris7 Paris75013

When Tony Blair and New Labour came to office in Britain late in the 20th century,John Atkinson Hobson( 1858-1940) was rediscovered and republished. In spite of his prolific work( over 50 books),he had sunk into oblivion. Yet John Maynard Keynes paid tribute to him( T he General T heory of Employment,Interest and Money,1936) and recognized his debt to this"heretic"of economics. Hobson's contribution to the history of economic thought is a major one,thanks to his stimulating analysis of under-consumption. His book Imperialism,A Study( 1902) was Lenin's bedside reading. But Hobson was no socialist: he w as a"N ew Liberal",belonging to a group of theoreticians who thought that classical liberalism had to be changed radically if it was to have any future.

关键词：自由主义布莱尔办公室经济

Large eddy simulation of boundary layer flow under cnoidal waves

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Acta Mechanica Sinica 2016年第1期32卷 22-37页

作者： Yin-JunLi Jiang-BoChen Ji-Fu zhou qiang Zhang Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences School of Aerospace Engineering Beijing Institute of Technology

Water waves in coastal areas are generally non- linear, exhibiting asymmetric velocity profiles with different amplitudes of crest and trough. The behaviors of the bound- ary layer under asymmetric waves are of great significance for sediment transport in natural circumstances. While pre- vious studies have mainly focused on linear or symmetric waves, asymmetric wave-induced flows remain unclear, par- ticularly in the flow regime with high Reynolds numbers. Taking cnoidal wave as a typical example of asymmetric waves, we propose to use an infinite immersed plate oscillat- ing cnoidally in its own plane in quiescent water to simulate asymmetric wave boundary layer. A large eddy simulation approach with Smagorinsky subgrid model is adopted to investigate the flow characteristics of the boundary layer. It is verified that the model well reproduces experimental and theoretical results. Then a series of numerical experiments are carried out to study the boundary layer beneath cnoidal waves from laminar to fully developed turbulent regimes at high Reynolds numbers, larger than ever studied before. Results of velocity profile, wall shear stress, friction coeffi- cient, phase lead between velocity and wall shear stress, and the boundary layer thickness are obtained. The dependencies of these boundary layer properties on the asymmetric degree and Reynolds number are discussed in detail.

关键词： Boundary layer structure Turbulence Largeeddy simulation Cnoidal wave