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Mapping non-laminar proton acceleration in laser-driven target normal sheath field

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High Power Laser Science and Engineering 2022年第1期10卷 10-16页

作者： C.y.Qin H.Zhang S.Li S.H.Zhai A.x.Li J.y.Qian J.y.Gui F.x.Wu Z.x.Zhang y.xu x.y.Liang y.x.leng B.F.Shen L.L.Ji R.x.Li State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Ultra-intense Laser Science Shanghai 201800China Department of Physics Shanghai Normal UniversityShanghai 200234China ShanghaiTech University Shanghai 201210China

We report on experimental observation of non-laminar proton acceleration modulated by a strong magnetic field in laser irradiating micrometer aluminum *** results illustrate the coexistence of ring-like and filamentation *** implement the knife edge method into the radiochromic film detector to map the accelerated beams,measuring a source size of 30-110μm for protons of more than 5 *** diagnosis reveals that the ring-like profile originates from low-energy protons far off the axis whereas the filamentation is from the near-axis high-energy protons,exhibiting non-laminar ***-in-cell simulations reproduced the experimental results,showing that the short-term magnetic turbulence via Weibel instability and the long-term quasi-static annular magnetic field by the streaming electric current account for the measured beam *** work provides direct mapping of laser-driven proton sources in the space-energy domain and reveals the non-laminar beam evolution at featured time scales.

关键词： knife-edge technique laser-plasma interaction non-laminar proton source target normal sheath acceleration Weibel instability

Acceleration of 60 MeV proton beams in the commissioning experiment of the SULF-10 PW laser

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High Power Laser Science and Engineering 2022年第4期10卷 36-44页

作者： A.x.Li C.y.Qin H.Zhang S.Li L.L.Fan Q.S.Wang T.J.xu N.W.Wang L.H.yu y.xu y.Q.Liu C.Wang x.L.Wang Z.x.Zhang x.y.Liu P.L.Bai Z.B.Gan x.B.Zhang x.B.Wang C.Fan y.J.Sun y.H.Tang B.yao x.y.Liang y.x.leng B.F.Shen L.L.Ji R.x.Li Z.Z.xu State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Shanghai Tech University Shanghai 201210China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBejing 100049China CAS Centerfor Excellence inUltra-intense Laser Science Shanghai 201800China College of Science University of Shanghai for Science and TechnologyShanghai 200093China Department of Physics Shanghai Normal UniversityShanghai 200234China

We report the experimental results of the commissioning phase in the 10 PW laser beamline of the Shanghai Superintense Ultrafast Laser Facility(SULF).The peak power reaches 2.4 PW on target without the last amplifying during the *** laser energy of 72±9 J is directed to a focal spot of approximately 6μm diameter(full width at half maximum)in 30 fs pulse duration,yielding a focused peak intensity around 2.0×10^(21)W/cm^(2).The first laser-proton acceleration experiment is performed using plain copper and plastic ***-energy proton beams with maximum cut-off energy up to 62.5 MeV are achieved using copper foils at the optimum target thickness of 4μm via target normal sheath *** plastic targets of tens of nanometers thick,the proton cut-off energy is approximately 20 MeV,showing ring-like or flamented density *** experimental results reflect the capabilities of the SULF-10 PW beamline,for example,both ultrahigh intensity and relatively good beam *** optimization for these key parameters is underway,where peak laser intensities of 10^(22)-10^(23)w/cm^(2)are anticipated to support various experiments on extreme field physics.

关键词： high-energy proton source laser-plasma interaction ultraintense lasers

Deposition of CrN Coatings by Filtered Cathodic Vacuum Arc

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Deposition of CrN Coatings by Filtered Cathodic Vacuum Arc

Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed Sintering and Post Treatment

Fifth International Conference on Surface Engineering

作者： J.L.Mo,M.H.Zhu,J.An,H.Sun,y.x.leng,N.Huang Key Laboratory of Advanced Technologies of Materials,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China

CrN coatings were deposited on cemented carbide substrates by filtered cathodic vacuum arc technique(FCVA).The effect of different deposition parameters:nitrogen partial pressure,substrate-bias voltage and preheating of the specimens,on the structural and mechanical properties of the coatings was investigated.x-ray diffraction analysis was used to determine the structure and the composition of the *** tribological behaviour and wear properties of the coatings against Si3N4 ball with diameter of 4 mm were studied under reciprocating sliding *** results showed that a smooth and dense CrN coating with best properties can be obtained provided a pure Cr interlayer was *** optimal deposition parameters were the nitrogen partial pressure of 0.1 Pa,substrate-bias voltage of-100 ***,preheating of the substrate was not good for improving the properties of the *** FCVA CrN coating showed high hardness and good wear resistance,which was probably attributed to its smooth surface and dense ***,the coating flaked off at relatively high normal load(20 N).The wear mechanism of the CrN coatings was a combination of abrasion and oxidation.

关键词： PVD Filtered cathodic vacuum arc technique CrN coating Tribological properties

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： x.y.yue S.y.Peng x.Zhang C.N.He y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

Ultra-high Ultra-short OPCPA Laser Development

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Ultra-high Ultra-short OPCPA Laser Development

Combining permissioned blockchain and Bayesian best-worst method for transparent supplier selection in supply chain management

CCAST“2002年全国强场激光物理”研讨会

作者： x.D.yang.Z.Z.xu,R.x.LI,Z.Q.Zhang,H.H.Lu, y.x.leng L.H.Lin, W.Q.Zhang, y.Fan, B.Tang, B.Z.Zhao Laboratory for High Intensity Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences

＜正＞MotivationsDeveloping 16.7TW OPCPA laser systemThe Latest Research Result on OPCPAA practical design of a 100TW OPCPA scheme Conclusion

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Science China(Technological Sciences) 2024年第8期67卷 2579-2593页

作者： LIU JiaJun ZHANG Jie leng JieWu Shanghai Engineering Research Center of Industrial Big Data and Intelligent System Institute of Artificial IntelligenceDonghua UniversityShanghai 201620China State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China

Supplier selection is an important business activity in order to realize the purchasing function in supply chain *** supplier selection process includes four stages,i.e.,bidding inviting,bidding,group decision-making,and results disclosure,involving the participation of manufacturing service demanders(MSDs),manufacturing service suppliers(MSSs),and ***,all the participants have raised concerns about the increased transparency in supplier ***,this study proposes a transparent supplier selection method by considering the engagement of *** this method,the Bayesian best-worst method(Bayesian BWM)is used to aggregate decision-makers'preferences into the overall optimal weights of the alternative MSSs,and the MSS with the largest weight is considered the suitable MSS for ***,blockchain is introduced to record the decision-making process information about supplier selection through a customized smart contract,where MSSs act as supervisors to supervise the decision-making process through the distributed consensus mechanism rather than directly participate in the decision-making ***,a case study of supplier selection in purchasing vibration acceleration sensors is *** result shows that the proposed method can support MSDs in selecting suitable MSS from alternative MSSs by aggregating decision-makers'preferences,and blockchain can provide credible information about the supplier selection process for MSSs,MSDs,and *** this way,the transparency of supplier selection is enhanced.

关键词： blockchain supplier selection supply chain transparency Bayesian BWM group decision-making

Shape embedding and retrieval in multi-ﬂow deformation

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Computational Visual Media 2024年第3期10卷 439-451页

作者： Baiqiang leng Jingwei Huang Guanlin Shen Bin Wang School of Software Tsinghua UniversityBeijingChina Huawei Technologies ShenzhenChina

We propose a unified 3D ﬂow frameworkfor joint learning of shape embedding and deformationfor different categories. Our goal is to recovershapes from imperfect point clouds by fitting thebest shape template in a shape repository afterdeformation. Accordingly, we learn a shape embeddingfor template retrieval and a ﬂow-based network forrobust deformation. We note that the deformationﬂow can be quite different for different shapecategories. Therefore, we introduce a novel multi-hubmodule to learn multiple modes of deformation toincorporate such variation, providing a network whichcan handle a wide range of objects from differentcategories. The shape embedding is designed to retrievethe best-fit template as the nearest neighbor in a latentspace. We replace the standard fully connected layerwith a tiny structure in the embedding that significantlyreduces network complexity and further improvesdeformation quality. Experiments show the superiorityof our method to existing state-of-the-art methods viaqualitative and quantitative comparisons. Finally, ourmethod provides efficient and flexible deformation thatcan further be used for novel shape design.

关键词： deformation shape retrieval embedding reconstruction

Controlled flight of a self-powered micro blimp driven by insect-sized flapping-wing thrusters

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Chinese Journal of Aeronautics 2024年第6期37卷 127-136页

作者： xian yU Zhiwei LIU Jiaming leng Mingjing QI xiaojun yAN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Beihang UniversityBeijng 100191China Beijing Key Laboratory of Aero-Engine Structure and Strength Beihang UniversityBeijing 100191China

Micro aerial platforms face significant challenges in achieving long controlled endurance as most of the energy is consumed to overcome the weight of the *** this study,we present a controllable micro blimp that addresses this issue through the use of a helium-filled *** micro blimp has a long axis of 23 cm and is propelled by four insect-sized flapping-wing thrusters,each weighing 80 mg and with a wingspan of 3.5 *** distributed thrusters enable controlled motions and provide the micro blimp with an advantage in flight endurance compared to multirotors or flapping-wing micro aerial vehicles at the same size *** enhance the performance of the controlled flight,we propose a wireless control module that enables manipulation from a distance of up to 100 ***,a smartphone application is developed to send instructions to the circuit board,allowing the blimp to turn left and right,ascend and descend,and achieve a combination of these movements *** findings demonstrate that this micro blimp is one of the smallest controlled self-powered micro blimps to date.

关键词： Microairvehicle Aircraft control Self-powered micro blimp Flapping-wing thruster Wireless flight

A Unified Motion Generation Approach for Quadruped L-S Walk and Trot Gaits Based on Linear Model Predictive Control

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Journal of Bionic Engineering 2024年第4期21卷 1707-1719页

作者： yapeng Shi Zhicheng He xiaokun leng Songhao Piao Lining Sun Harbin Institute of Technology No.92 West Dazhi StreetHarbin150001HeilongjiangChina yanshan University No.438 West Hebei AvenueQinhuangdao066004HebeiChina

The goal of this paper is to develop a unified online motion generation scheme for quadruped lateral-sequence walk and trot gaits based on a linear model predictive control ***,the dynamics of the linear pendulum model is formulated over a predictive horizon by dimensional *** gait pattern conversion,the lateral-sequence walk and trot gaits of the quadruped can be regarded as unified biped gaits,allowing the dynamics of the linear inverted pendulum model to serve quadruped motion *** addition,a simple linearization of the center of pressure constraints for these quadruped gaits is developed for linear model predictive control ***,the motion generation problem can be solved online by quadratic programming with foothold *** is demonstrated that the proposed unified scheme can generate stable locomotion online for quadruped lateral-sequence walk and trot gaits,both in simulation and on *** results show significant performance improvements compared to previous ***,the results also suggest the linearly simplified scheme has the ability to robustness against unexpected disturbances.

关键词： Motion generation Gait pattern conversion Model predictive control Quadruped locomotion