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IET Cyber-Systems and Robotics 2023年第1期5卷 36-50页

作者： xing Gao Xin su Aimin An Haochen Zhang College of Electrical and Information Engineering Lanzhou University of TechnologyLanZhouGanSuChina

In this study,a robust model predictive controller is designed for the trajectory tracking problem of non-holonomic constrained wheeled mobile robot based on an elliptic invariant set *** controller is based on a time-varying error model of robot kinematics and uses linear matrix inequalities to solve the robust tracking problem taking uncertainties into *** uncertainties are modelled by linear fractional transform form to contain both parameter perturbations and external *** control strategy consists of a feedforward term that drives the centre of the ellipse to the reference point and a feedback term that converges the uncertain system state error to the equilibrium *** strategy stabilises the nominal system and ensures that all states of the uncertain system remain within the ellipsoid at each step,thus achieving robust stability of the uncertain ***,the robustness of the algorithm and its resistance to disturbances are verified by simulation and experiment.

关键词： mobile robots robot control robot kinematics robustness

Theoretical analysis of long-lived radioactive waste in pressurized water reactor

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Nuclear Science and Techniques 2021年第7期32卷 55-71页

作者： ze-Xin Fang Meng Yu Ying-Ge Huang Jin-Bei Chen Jun su Long Zhu Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

Background The accelerator-driven subcritical transmutation system(ADS)is an advanced technology for the harmless disposal of nuclear waste.A theoretical analysis of the ingredients and content of nuclear waste,particularly long-lived waste in a pressurized water reactor(PWR),will provide important information for future spent fuel *** The present study is an attempt to investigate the yields of isotopes in the neutron-induced fission process and estimate the content of long-lived ingredients of nuclear waste in a *** We combined an approximation of the mass distribution of five Gaussians with the most probable charge model(Zp model)to obtain the isotope yields in the^(235)U(n,f)and^(239)Pu(n,f)*** potential energy surface based on the concept of a di-nuclear system model was applied to an approximation using five Gaussian functions.A mathematical formula for the neutron spectrum in a PWR was established,and sets of differential equations were solved to calculate the content of long-lived nuclides in a *** The calculated isotopic fission yields were in good agreement with the experimental *** for 238U,the contents of^(239)Pu,^(240)Pu,^(241)Pu,^(242)Pu,^(237)Np,^(235)U,and^(236)U are predominant in the PWR after reaching a discharge *** addition,some isotope pairs of heavy nuclei reach a similar value after stabilization,which can be explained by the decay chain and effective fission *** fission fragments,we simulated the content evolution of some long-lived nuclides^(90)Sr,^(107)Pd,^(135)Cs,and their isobars^(90)Rb,^(107)Rh,and^(135)Xe during a fuel cycle in a *** variations in the inventories of uranium and plutonium were in good agreement with the data in Daya *** A new method is proposed for the prediction of the isotopic fission *** inventory of long-lived nuclides was analyzed and predicted after reaching a discharge burnup.

关键词： Radiotoxicity PWR Five Gaussians Long-lived nuclides Fissionfragmentsyields

Involvement of Hydrogen Peroxide Generated by Polyamine Oxidative Degradation in the Development of Lateral Roots in Soybean

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Journal of Integrative Plant Biology 2006年第4期48卷 426-432页

作者： Guo-xing su Wen-Hua Zhang You-Liang Liu College of Life Sciences Nanjing Agricultural University Soybean Research Institute Nanjing Agricultural University National Center of Soybean Improvement Ministry of Agriculture Nanjing 210095 China College of Life Sciences Suzhou University Suzhou 215006 China

In order to determine whether hydrogen peroxide （H2O2） generated by polyamlne oxidative degradation Is Involved In the development of lateral roots In soybean, the length and the number of lateral roots, the actlvltlea of polyamlne oxldases and dlamlne oxldases, and the endogenous free polyamlne and H2O2 content were analyzed In soybean （Giycine max （Linn.） Merr.） main roots of 2-d-old seedlings after treatments for 2 d with exogenous β-hydroxyethylhydrazine （an Inhibitor of polyamlne oxldases）, H202, putresclne, cyclohexylamlne （an Inhibitor of spermidine synthase） or N,N＇-dimethylthlourea （a scavenger of hydrogen peroxide）.β-hydroxyethylhydrazlne treatment strongly Inhibited the development of lateral roots In soybean seedlings, reduced the activities of polyamine oxldases and dlamlne oxidases, decreased H2O2 levels, and led to the accumulation of endogenous polyamlnes In the main roots. The inhibitory effect of β-hydroxyethylhydrazlne on root development could be alleviated by exogenously applied 10 μmol/L H2O2 （a major product of polyamlne oxidation）. Treatment with cyclohexylamlne and putresclne promoted root growth slightly, but treatment with cyclohexylamlne plus N,N＇dlmethylthlourea or putresclne plus N,N＇-dlmethylthlourea prevented the development of soybean lateral roots. The effects of these treatments on the development of soybean lateral roots were consistent with the changes In endogenous H2O2 levels. These results suggest that the development of soybean lateral roots Is associated with the oxidative degradation of polyamlnes, and that their products, especially H2O2, are likely to play an Important role In the growth of soybean lateral roots.

关键词： β-hydroxyethylhydrazine hydrogen peroxide polyamine oxidases polyamines soybean lateral roots.

QCD Axial Anomaly Enhances theηη'Decay of the Hybrid Candidateη1(1855)

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Chinese Physics Letters 2022年第5期39卷 29-35页

作者： Hua-xing Chen Niu su Shi-Lin Zhu School of Physics Southeast UniversityNanjing 210094China School of Physics and Center of High Energy Physics Peking UniversityBeijing 100871China

We study the hybrid mesons with the exotic quantum number I^(G)J^(PG)=0+1-+and investigate their decays into theηη’,a1(1260)π,f1(1285)η,f1(1420)η,K*(892)■,K1(1270)■,and K1(1400)■*** is found that the QCD axial anomaly enhances the decay width of theηη’channel although this mode is strongly suppressed by the small p-wave phase *** results support the interpretation of theη1(1855)recently observed by BESⅢas the ssg hybrid meson of I^(G)J^(PC)=0^(+)1^(-+).The QCD axial anomaly ensures theηη’decay mode to be a characteristic signal of the hybrid nature of theη1(1855).

关键词： BESⅢ QCD mode

Efficacy of insect-resistance Bt/Cp TI transgenes in F5–F7generations of rice crop–weed hybrid progeny: implications for assessing ecological impact of transgene flow

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Science Bulletin 2015年第18期60卷 1563-1571页

作者： Xiao Yang Lei Li xing xing Cai Feng Wang Jun su Bao-Rong Lu Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Department of Ecology and Evolutionary Biology Fudan University Fujian Provincial Key Laboratory of Genetic Engineering for Agriculture Fujian Academy of Agricultural Sciences

Ecological impact of transgene flow into pop- ulations of wild/weedy relatives is associated with fitness effects in hybrid progeny. Most studies assessing fitness effects focus essentially on early-generation hybrid progeny. However, whether the transgenes remain effective and durable in advanced generations of hybrid progeny remains unclear. We conducted a common garden experi- ment with Fs-F7 hybrid progeny derived from crosses between insect-resistant transgenic （Bt/CpTI） rice and weedy rice, to examine their insect resistance and fitness effects of transgenes on progeny. Hybrid progeny were grown under different insect pressures and cultivation modes where insect damage and fitness-related traits were measured in the same growth season. Plants with transgenes showed significantly lower insect damage （10 % vs. 32 %） and higher fecundity （551 vs. 392 seeds/plant） than those without transgenes in the efficacy of transgenes Fs-F7 populations, suggesting for insect resistance. Fitness benefits of the transgenes were similar among the Fs-F7 populations, indicating the stability of transgenic effects. A positive correlation between insect index and fecundity change was detected, stressing the important role of ambient insect pressures in assessing fitness effects caused by insect-resistance transgenes. Our results have important implications for assessing ecological impacts caused by transgene flow to wild/weedy relatives. For cost-effec- tiveness, the experimental estimation of fitness effects is probably sufficient based on data from hybrids in early generations. Given that fitness effects of insect-resistance transgenes are associated with ambient insect pressure, ecological risk assessment on transgene flow should consider this variable in experimental design, reasonably reflecting actual situations in wild/weedy populations.

关键词： Introgressiogeneration,Insect-resistance transgenen Weedy rice Fitness Advanced Risk assessment

Electrostatic force of dust deposition originating from contact between particles and photovoltaic glass

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Chinese Physics B 2021年第10期30卷 267-273页

作者： xing-Cai Li Juan Wang Guo-Qing su School of Physics and Electronic-Electrical Engineering Ningxia UniversityYinchuan 750021China Ningxia Key Laboratory of Intelligent Sensing&Desert Information Ningxia UniversityYinchuan 750021China Xinhua College of Ningxia University Yinchuan 750021China

Charged photovoltaic glass produces an electrostatic *** electrostatic field exerts an electrostatic force on dust particles,thus making more dust particles deposited on the *** this paper,the contact electrification between the deposited dust particles and the photovoltaic glass is ***,the surface charge density model of the photovoltaic glass and the electrostatic force of charged particles are *** results show that with the increasing of the particle impact speed and the inclination angle of the photovoltaic panel,the charges on particles increase to different *** a given condition,the electrostatic forces acting on the charged particles at different positions above the glass plate form a bell-shaped distribution at a macro level,and present a maximum value in the center of the *** the distance between the particle and the charged glass decreases,the electrostatic force exerted on the particle increases significantly and fluctuates ***,its mean value is still higher than the force caused by gravity and the adhesion force,reported by some ***,we suggest that photovoltaic glass panels used in the severe wind-sand environment should be made of an anti-static transparent material,which can lessen the dust particles accumulated on the panels.

关键词： particle electrification electrostatic force photovoltaic glass dust deposition

A deep trench super-junction LDMOS with double charge compensation layer

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Journal of Semiconductors 2022年第10期43卷 103-108页

作者： Lijuan Wu Shaolian su xing Chen Jinsheng zeng Haifeng Wu Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering School of Physics&Electronic ScienceChangsha University of Science&TechnologyChangsha 410114China

A deep trench super-junction LDMOS with double charge compensation layer(DC DT SJ LDMOS)is proposed in this *** to the capacitance effect of the deep trench which is known as silicon-insulator-silicon(SIS)capacitance,the charge balance in the super-junction region of the conventional deep trench SJ LDMOS(*** SJ LDMOS)device will be broken,resulting in breakdown voltage(BV)of the device *** DT SJ LDMOS solves the SIS capacitance effect by adding a vertical variable doped charge compensation layer and a triangular charge compensation layer inside the *** SJ LDMOS ***,the drift region reaches an ideal charge balance state *** electric field is optimized by double charge compensation and gate field plate so that the breakdown voltage of the proposed device is improved sharply,meanwhile the enlarged on-current region reduces its specific *** simulation results show that compared with the *** SJ LD-MOS,the BV of the DC DT SJ LDMOS has been increased from 549.5 to 705.5 V,and the R_(on,sp) decreased to 23.7 mΩ·cm^(2).

关键词： double charge compensation layer super-junction deep trench SIS capacitance

Effect of F-Rich Fluids on the A-Type Magmatism and Related Metal Mobilization:New Insights from the Fogang-Nankunshan-Yajishan Igneous Rocks in Southeast China

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Journal of Earth Science 2022年第3期33卷 591-608页

作者： xing Ding Koulin su Haibo Yan Jinlong Liang Weidong sun State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Sciences Guangzhou 510640China Geological survey Institute of Guangzhou Guangzhou 510640China Center of Deep Sea Research Institute of OceanographyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Department of Geochemistry Chengdu University of TechnologyChengdu 610059China

About 45%of tungsten,~20%of tin,and~9%of fluorite of known world reserves are associated with Late Mesozoic igneous rocks,Southeast(SE)*** we demonstrate that Fogang granite,the largest inland batholith,is mainly of A2-type that is commonly found in post-orogenic settings and experienced plate subduction induced *** contrast,the Yajishan syenite and Nankunshan granite intruding the Fogang granite~20 Ma later are of A1-type formed in intraplate *** found that F-rich fluid fractionation,which could make the decline of Ga/Al ratio,total(Nb+Y+Ce+Zr)and Zr concentrations,Nb/Ta and Zr/Hf ratios,leads to chemical variations of a few Fogang granites changing from A2-type to highly fractionated or I-and S-type *** and Frich fluid fractionations,as well as crustal contamination most likely derived from the Fogang granite,result in some Nankunshan granites developing from A1-type into *** late-or post-magmatic processes should be taken into account carefully when discriminating the petrogenetic types of igneous rocks,especially for the A2-type *** with the distribution of 180-140 Ma A1-and A2-type igneous rocks,rare metal deposits,and fluorite deposits in SE China,we highlight the significant role of slab-released F-rich fluids in formation of A-type suites and subsequent chemical differentiation and rare metal and fluorine mineralization.A model of flat-slab northeastward rollback is thus proposed,in which the subduction front reached somewhere near Fogang and then started to roll back at~165 *** inland Jurassic granites of SE China represent a unique locality for formation of A-type suites and their associated *** granites are not anorogenic,but they are the result of slab rollback from a flat slab,founding of that slab at shallow levels,and metasomatism of by F-rich fluids related to slab heating by the asthenosphere.

关键词： A-type granite alkaline F-rich fluids slab rollback rare metal rare earth elements Nb/Ta

Constrained docking control for shipborne UAV SideArm recovery

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Chinese Journal of Aeronautics 2024年第5期37卷 39-59页

作者： Zikang su Zhuolin xing Xuebing LI Chuntao LI Xinwei WANG Honglun WANG College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Engineering and Materials Science Queen Mary University of LondonLondon E14NSUK School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

In this work,we sought to investigate constrained docking control during shipborne SideArm recovery of an Unmanned Aerial Vehicle(UAV)under preassigned safe docking constraints,rough ocean environments,and different initial *** aim was to solve the UAV tracking-lag problem that manifests when attempting to dock with a rapidly moving SideArm and to improve the accuracy and rapidity of ***,together with the formulations of the shipborne SideArm system and environmental airflows,the affine nonlinear dynamics of the hook was established to reduce tracking ***,echo state network approximators with good approximation capacity and low computational consumption were designed to accurately approximate the UAV’s unknown nonlinear *** feedforward compensation provided by these approximators,a nonlinear-mapping-based constrained docking control law was developed for shipborne SideArm recovery of *** approach to controlling the docking trajectory and the forward docking speed of the UAV can achieve rapid and exact docking with a moving SideArm,without violating the preassigned safe docking-constraint *** under different docking scenarios were used to validate the effectiveness and advantages of the proposed docking-control algorithm.

关键词： SideArm recovery Unmanned aerial vehicle Docking control Nonlinear mapping Echo state network

Aerial-ground collaborative routing with time constraints

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Chinese Journal of Aeronautics 2023年第2期36卷 270-283页

作者： Jiahao xing Lichen su Wenjing HONG Lu TONG Renli LYU Wenbo DU School of Electronics and Information Engineering Beihang UniversityBeijing 100091China School of Future Aerospace Technology/Shen Yuan Honors College Beihang UniversityBejing 100091China School of Automation Science and Electrical Engineering Beihang UniversityBejing 100091China Guangdong Provincial Key Laboratory of Brain-Inspired Intelligent Computation Shenzhen 518055China Department of Computer Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Research Institute of Frontier Science Beihang UniversityBeijing 100083China CAAC Key Laboratory of General Aviation Operation Civil Aviation Management Institute of ChinaBeijing 100102China

The advancement of autonomous technology makes electric-powered drones an excellent choice for flexible logistics services at the last mile delivery *** reach a balance between green transportation and competitive edge,the collaborative routing of drones in the air and trucks on the ground is increasingly invested in the next generation of delivery,where it is particularly reasonable to consider customer time windows and time-dependent travel times as two typical time-related factors in daily *** this paper,we propose the Vehicle Routing Problem with Drones under Time constraints(VRPD-T)and focus on the time constraints involved in realistic scenarios during the delivery.A mixed-integer linear programming model has been developed to minimize the total delivery completion ***,to overcome the limitations of standard solvers in handling large-scale complex issues,a space-time hybrid heuristic-based algorithm has been developed to effectively identify a high-quality *** numerical results produced from randomly generated instances demonstrate the effectiveness of the proposed algorithm.

关键词： Aerial-ground collaborative delivery Mixed-integer programming Space-time hybrid heuristic algorithm Vehicle routing problem with drones Time-dependent travel times