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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1190-1201页

作者： Xiangqian Yao Hao Sun Zhijia zhao yu Liu School of Automation Science and Engineering South China University of TechnologyGuangzhou 510640China Yongjiang Laboratory Ningbo 315202 School of Astronautics Harbin Institute of TechnologyHarbin 150001China School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou 510006China

For bipartite angle consensus tracking and vibration suppression of multiple Timoshenko manipulator systems with time-varying actuator faults,parameter and modeling uncertainties,and unknown disturbances,a novel distributed boundary event-triggered control strategy is proposed in this *** contrast to the earlier findings,time-varying consensus tracking and actuator defects are taken into account *** addition,the constructed event-triggered control mechanism can achieve a more flexible design because it is not required to satisfy the input-to-state *** achieve the control objectives,some new integral control variables are given by using back-stepping technique and boundary ***,adaptive neural networks are applied to estimate system *** the proposed event-triggered scheme,control inputs can reduce unnecessary ***,tracking errors and vibration states of the closed-looped network can be exponentially convergent into some small fields,and Zeno behaviors can be *** last,some simulation examples are given to state the effectiveness of the control algorithms.

关键词： Vibration satisfy bipartite

A flat-foldable equiangular spiral folding pattern inspired by sunflowers for deployable structures

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Chinese Journal of Aeronautics 2024年第6期37卷 425-438页

作者： Shuangqing yu Jinguo LIU Pengyuan zhao Yingying TANG State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China

Flasher origami pattern has been widely utilized to improve the stowage efficiency of deployable ***,flasher origami cannot be folded fully flat,and they still have great potential for optimization in terms of storage volume and folding *** this paper,a flat foldable equiangular spiral folding pattern inspired by the sunflower disk is ***,a parametric design method for this equiangular spiral crease diagram is introduced in ***,a kinematic model of the equiangular spiral folding pattern is established based on the kinematic equivalence between rigid origami and spherical linkages.A simulation of the developed model demonstrates that the equiangular spiral folding pattern can be folded *** the folded ratio as an evaluation index,the calculated results and experiments show that the equiangular spiral crease pattern can yield fewer creases and improve stowage efficiency in comparison to flasher origami *** spiral folding pattern can save a considerable amount of space and provide a new approach to spatially deployable structures.

关键词： Flasher origami Sunflower-inspired Deployable structures Flat-foldability Equiangular spiral folding pattern

The Study of Unusual Emission from PSR B1859+07 using FAST

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Research in Astronomy and Astrophysics 2022年第4期22卷 1-10页

作者： Lin Wang ye-zhao yu Feifei Kou Kuo Liu Xinxin Wang Bo Peng CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing100101China Qiannan Normal University for Nationalities Duyun558000China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing100049China Max-Plank-Institut für Radioastronomie Auf dem Hügel 69BonnD-53121Germany Xinjiang Astronomical Observatories Chinese Academy of SciencesUrumqi830011China United World College of Changshu China Changshu215500China

We present simultaneous broad-band radio observations on the abnormal emission mode from PSR B1859+07using the Five-hundred-meter Aperture Spherical radio Telescope(FAST).This pulsar shows peculiar emission,which takes the form of occasional shifts of emission to an early rotational phase and mode change of emission at the normal *** confirm all these three emission modes with our data sets,including the B(burst)and Q(quiet)modes of the non-shifted pulses and the emission shift mode with a quasi-periodicity of 155 *** also identify a new type of emission shift event,which has emission at the normal phase during the *** studied polarization properties of these emission modes in detail,and found that they all have similar polarization angle curve,indicating the emissions of all these three modes are from the same emission height.

关键词： pulsars:general pulsars:individual(B1859+07) methods:observational

Numerical simulation analysis of wind field above pavement surface in different landforms by computational fluid dynamics approach

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 559-573页

作者： Jian Ouyang zhao Jiang Leiyu ye Jing Li Peng Cao School of Civil Engineering and Architecture Hainan UniversityHaikou 570000China School of Transportation and Logistics Dalian University of TechnologyDalian 116024China Hexagon Manufacturing Intelligence(Qingdao)Co. Ltd.Qingdao 266000China China Tower Co. Ltd.Dalian BranchDalian 116024China Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China

The temperature and moisture of the pavement structure can be greatly influenced by the wind speed above pavement *** wind speed above pavement surface not only is dominated by the wind speed of atmosphere,but also it is highly related to the landform and buildings around ***,currently there are no studies about the wind field above pavement surface in consideration of the effect of the landform and buildings.A simulation method,which is combined with geographic information system(GIS),wind data from meteorological observatory and computational fluid dynamics(CFD)software,is employed to study the effect of the landform and the wind speed of atmosphere on the wind field above pavement *** cases are studied,including an urban road,a coastal road and a mountainous ***,the wind field distribution above road surface in different wind directions was studied in our *** indicate that the wind field above pavement surface can be greatly affected by the landforms,buildings and wind *** simulation method can provide reliable results for the wind field above pavement *** maximum relative errors between simulated and measured wind speed can be less than 20%in the analysis of the three *** is recommended that the CFD simulation method is a good tool to accurately know the wind field above pavement surface.

关键词： Wind field above pavement surface Computational fluid dynamics Landforms Geographic information system Simulation

Deadline-Constrained and Cost-Effective Multi-Workflow Scheduling with Uncertainty in Cloud Control Systems

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Journal of Systems Science & Complexity 2024年第5期37卷 1861-1886页

作者： ye Lingjuan YANG Liwen XIA yuanqing ZHAN yufeng zhao Xinchao School of Science Beijing University of Posts and Telecommunications Key Laboratory of Mathematics and Information Networks Beijing University of Posts and Telecommunications Ministry of Education School of Automation Nanjing University of Information Science and Technology School of Automation Beijing Institute of Technology

In cloud control systems, generating an efficient and economical workflow scheduling strategy for deadline-constrained workflow applications, especially in uncertain multi-workflow dynamic scheduling processes, is a crucial challenge. To optimize the total cost of workflow scheduling, the authors propose a cost-driven heuristic scheduling algorithm F-MWSA which consists of two phases:Fuzzy deadline distribution and fuzzy task scheduling. In the fuzzy deadline distribution phase, a new workflow deadline distribution strategy with fuzziness is designed to obtain the sub-deadline constraint of each task. The fuzzy task scheduling phase focuses on a cost-effective strategy to assign tasks to cloud resources, reducing multi-workflow scheduling costs. Performance evaluations on five real-world workflows demonstrate that the proposed F-MWSA outperforms the baseline policy in terms of total cost, success ratio, resource utilization, and makespan.

关键词： Cloud computing cost-effective deadline constraint multi-workflow scheduling uncertainty

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Photoredox-catalyzed C-glycosylation of peptides with glycosyl bromides

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Chinese Chemical Letters 2024年第6期35卷 263-267页

作者： Chen Li Ziyuan zhao Shouyun yu State Key Laboratory of Analytical Chemistry for Life Science Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Glycosyl radicals,produced under mild photoredox conditions,show unique utility in the preparation of C-linked *** herein report the construction of C-glycosidic bonds on α,β-dehydroalanine(DHA)of peptides with easily available glycosyl bromides as glycosyl radical precursors under highly anomeric control,leading to C-glycosylation modifications of *** method not only has outstanding functional group compatibility,but also is feasible in near-physiological conditions(pH~7 and temperature T≤37℃ in aqueous media).

关键词： Glycosylation C-Glycosides Glycopeptides Dehydroalanine Photoredox catalysis

Visible Light-Induced[3+2]Annulation Reaction of Alkenes with Vinyl Azides:Direct Synthesis of Functionalized Pyrroles

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Chinese Journal of Chemistry 2024年第2期42卷 151-156页

作者： Ming Yang Xin-yu Wang Jie Wang yu-Long zhao Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Faculty of ChemistryNortheast Normal UniversityChangchunJilin 130024China

A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye *** substrate scope and high functional group tolerance were demonstrated by more than 50 *** reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.

关键词： Photocatalysis Vinyl azides Alkenes Pyrroles Annulation Radical reactions

Transcriptomic and cellular decoding of scaffolds-induced suture mesenchyme regeneration

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International Journal of Oral Science 2024年第2期16卷 306-321页

作者： Jiayi Wu Feifei Li Peng yu Changhao yu Chuyi Han Yitian Wang Fanyuan yu Ling ye State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&West China Hospital of Stomatology Sichuan UniversityChengduChina State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Cariology and Endodontics West China Hospital of StomatologySichuan UniversityChengduChina State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Pediatric Dentistry West China Hospital of StomatologySichuan UniversityChengduChina

Precise orchestration of cell fate determination underlies the success of scaffold-based skeletal *** extensive studies on mineralized parenchymal tissue rebuilding,regenerating and maintaining undifferentiated mesenchyme within calvarial bone remain very challenging with limited advances *** knowledge has evidenced the indispensability of rebuilding suture mesenchymal stem cell niches to avoid severe brain or even systematic *** to date,the absence of promising therapeutic biomaterials/scaffolds *** reason lies in the shortage of fundamental knowledge and methodological evidence to understand the cellular fate regulations of *** address these issues,in this study,we systematically investigated the cellular fate determinations and transcriptomic mechanisms by distinct types of commonly used calvarial *** data elucidated the natural processes without scaffold transplantation and demonstrated how different scaffolds altered in vivo cellular responses.A feasible scaffold,polylactic acid electrospinning membrane(PLA),was next identified to precisely control mesenchymal ingrowth and self-renewal to rebuild non-osteogenic suture-like tissue at the defect center,meanwhile supporting proper osteointegration with defect bony ***,transcriptome analysis and cellular mechanisms underlying the well-orchestrated cell fate determination of PLA were *** study for the first time cellularly decoded the fate regulations of scaffolds in suture-bony composite defect healing,offering clinicians potential choices for regenerating such complicated injuries.

关键词： injuries healing suture

Characteristics of a pre-combustion plasma jet igniter

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Chinese Journal of Aeronautics 2024年第7期37卷 178-189页

作者： Jinlu yu Baowen ZHANG Yang yu Bingbing zhao Lei ZHANG Aviation Engineering School Air Force Engineering UniversityXi’an 710038China Equipment Management and Unmanned Aerial Vehicle Engineering School Air Force Engineering UniversityXi’an 710038China

Plasma ignition technology has delivered good performance in the aerospace industry. In this study, a pre-combustion plasma jet igniter was designed, and its characteristics were examined from three aspects: the morphology, temperature, and discharge characteristics and process of ignition. Images of the OH distribution were obtained by using an OH Planar Laser-Induced Fluorescence(OH-PLIF) experimental system. Results have shown that the proposed plasma jet had a higher OH concentration, longer length, and larger area than those of a traditional igniter. The stability of discharge of the igniter was improved as the equivalence ratio φ was increased, and reducing gas flow reduced the pulsation of the plasma jet. When the input current was increased from 15A to 35 A, the highest average temperature increased from 5127 K to 7987 K. An increase in the equivalence ratio reduced the region of arc ionization, but expanded the regions of the core combustion reaction and the outer flame. Herein, this study has obtained a deep understanding of the jet and ignition law and developed a new idea for the application of plasma in the ignition field.A pre-combustion plasma jet igniter can significantly improve the efficiency of ignition and shorten the ignition process compared with a traditional igniter.

关键词： Pre-combustion plasma igniter Plasma Jet temperature field Ignition process Arc Flame

Femtosecond laser-induced periodic surface structures on hard and brittle materials

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Science China(Technological Sciences) 2024年第1期67卷 19-36页

作者： zhao GuoXu WANG Gong LI yunFei WANG Lei LIAN yuDong yu yu zhao Hui WANG yuLei LU ZhiWei Center for Advanced Laser Technology Hebei University of TechnologyTianjin 300401China Hebei Key Laboratory of Advanced Laser Technology and Equipment Tianjin 300401China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China School of Information and Electrical Engineering Hebei University of EngineeringHandan 056038China

Hard and brittle materials have high hardness,excellent optical stability,chemical stability,and high thermal ***,they have huge application potential in various fields,such as optical components,substrate materials,and quantum information,especially under harsh conditions,such as high temperatures and high *** laser direct writing technology has greatly promoted the development of femtosecond laser-induced periodic surface structure(Fs-LIPSS or LIPSS by a femtosecond laser)applications of hard and brittle materials due to its high precision,controllability,and three-dimensional processing *** far,LIPSSs have been widely used in material surface treatment,optoelectronic devices,and ***,a consensus has not been reached regarding the formation mechanism of LIPSSs on hard and brittle *** this paper,three widely accepted LIPSS formation mechanisms are introduced,and the characteristics and applications of LIPSSs on diamonds,silicon,silicon carbide,and fused silica surfaces in recent years are *** addition,the application prospects and challenges of LIPSSs on hard and brittle materials by a femtosecond laser are discussed.

关键词： laser-induced periodic surface structures hard and brittle materials femtosecond laser