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The importance of Righi-Leduc heat flux to the ablative Rayleigh-Taylor instability during a laser irradiating targets

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High Power Laser Science and Engineering 2024年第3期12卷 9-19页

作者： Ye Cui Xiao-Hu Yang Yan-Yun Ma Guo-Bo Zhang Bi-hao Xu ze-hao chen ze Li Fu-Qiu Shao Jie Zhang Department of Nuclear Science and Technology National University of Defense TechnologyChangshaChina College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangshaChina Department of Physics National University of Defense TechnologyChangshaChina Key Laboratory for Laser Plasmas(Ministry of Education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Centre of IFSA Shanghai Jiao Tong UniversityShanghaiChina

The Righi±Leduc heat flux generated by the self-generated magnetic field in the ablative Rayleigh±Taylor instability driven by a laser irradiating thin targets is studied through two-dimensional extended-magnetohydrodynamic *** perturbation structure gets into a low magnetization state though the peak strength of the self-generated magnetic field could reach hundreds of *** Righi±Leduc effect plays an essential impact both in the linear and nonlinear stages,and it deflects the total heat flux towards the spike *** to the case without the self-generated magnetic field included,less heat flux is concentrated at the spike tip,finally mitigating the ablative stabilization and leading to an increase in the velocity of the spike *** is shown that the linear growth rate is increased by about 10%and the amplitude during the nonlinear stage is increased by even more than 10%due to the feedback of the magnetic field,*** results reveal the importance of Righi±Leduc heat flux to the growth of the instability and promote deep understanding of the instability evolution together with the self-generated magnetic field,especially during the acceleration stage in inertial confinement fusion.

关键词： amplitude linear growth rate Rayleigh-Taylor instability Righi-Leduc heat flux self-generated magnetic field

Mazabraud’s syndrome in female patients:Two case reports

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World Journal of Orthopedics 2024年第6期15卷 593-601页

作者： Xiu-Mao Li ze-hao chen Ke-Yi Wang Jun-Nan chen Zhao-Nong Yao Yu-Hong Yao Xiao-Wei Zhou Nong Lin Department of Orthopedics The Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009Zhejiang ProvinceChina Orthopedics Research Institute Zhejiang UniversityHangzhou 310009Zhejiang ProvinceChina State Key Laboratory of Transvascular Implantation Devices Hangzhou 310009Zhejiang ProvinceChina Songyang Branch of the Second Affiliated Hospital School of MedicineZhejiang UniversityLishui 331124Zhejiang ProvinceChina

BACKGROUND Mazabraud’s syndrome(MS)is a rare and slowly progressive benign disease characterized by the concurrent presence of fibrous dysplasia of bone and intramuscular myxoma,and is thought to be associated with mutations of the GNAS *** date,only about 100 cases of MS have been reported in the literature,but its standard treatment strategy remains *** SUMMARY We report two cases of MS in young women who underwent different treatments based on their symptoms and disease *** first patient,aged 37,received internal fixation and intravenous bisphosphonate for a pathological fracture of the right femoral neck,excision of a right vastus medialis myxoma was subsequently performed for pain control,and asymptomatic psoas myxomas were monitored without *** testing confirmed a GNAS gene mutation in this *** second patient,aged 24,underwent right vastus intermedius muscle myxoma resection,and conservative treatment for fibrous dysplasia of the *** patients were followed-up for 17 months and 3 years,respectively,and are now in a stable *** Various treatments have been selected for MS patients who suffer different *** main treatment for myxomas is surgical resection,while fibrous dysplasia is selectively treated if the patient experiences pathological fracture or severe ***,given the documented instances of malignant transformation of fibrous dysplasia in individuals with MS,close follow-up is necessary.

关键词： Mazabraud's syndrome Fibrous dysplasia Intramuscular myxoma Bisphosphonate Case report

Observation of the density dependence of the closed-channel fraction of a 6Li superfluid

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National Science Review 2022年第10期9卷 105-111页

作者： Xiang-Pei Liu Xing-Can Yao hao-ze chen Xiao-Qiong Wang Yu-Xuan Wang Yu-Ao chen Qijin chen Kathryn Levin Jian-Wei Pan Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics University of Science and Technology of China Shanghai Branch CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Shanghai Research Center for Quantum Sciences James Franck Institute University of Chicago

Atomic Fermi gases provide an ideal platform for studying pairing and superfluid physics,using a Feshbach resonance between closed-channel molecular states and open-channel scattering *** particular interest is the strongly interacting *** show that the closed-channel fraction Zccprovides an effective probe for important many-body interacting effects,especially through its density dependence,which is absent from two-body theoretical *** we measure Zccas a function of interaction strength and the Fermi temperature TF in a trapped 6Li superfluid throughout the entire Bardeen-Cooper-Schrieffer-Bose-Einstein-condensate crossover,in quantitative agreement with theory when important thermal contributions outside the superfluid core are taken into *** from the deep-BEC regime,the fraction Zccis sensitive to *** particular,our data show Zcc∝TFαwith α=1/2at unitarity,in quantitative agreement with calculations of a two-channel pairing fluctuation theory,and a increases rapidly into the BCS regime,reflecting many-body interaction effects as predicted.

关键词： closed-channel fraction density dependence strongly interacting Fermi gas many-body effect

Experimental research on the launching system of auxiliary charge with filter cartridge structure

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Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-Jun chen ze He Hong-hao Ma Lu-Qing Wang Zhao-Wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the *** combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the *** breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the *** this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the *** proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the *** order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are *** experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak *** projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,*** muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the *** the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

DLF-YOLOF:an improved YOLOF-based surface defect detection for steel plate

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Journal of Iron and Steel Research International 2024年第2期31卷 442-451页

作者： Guang-hu Liu Mao-xiang Chu Rong-fen Gong ze-hao Zheng School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051LiaoningChina

Surface defects can affect the quality of steel *** methods based on computer vision are currently applied to surface defect detection of steel ***,their real-time performance and object detection of small defect are still *** improved object detection network based on You Only Look One-level Feature(YOLOF)is proposed to show excellent performance in surface defect detection of steel plate,called ***,the anchor-free detector is used to reduce the network ***,deformable convolution network and local spatial attention module are introduced into the feature extraction network to increase the contextual information in the feature ***,the soft non-maximum suppression is used to improve detection accuracy ***,data augmentation is performed for small defect objects during training to improve detection *** show the average precision and average precision for small objects are 42.7%and 33.5%at a detection speed of 62 frames per second on a single GPU,*** shows that DLF-YOLOF has excellent performance to meet the needs of industrial real-time detection.

关键词： Steel surface defects detection YOLOF Anchor-free detector Small object detection Real-time detection

Research progresses and prospects of multi-sphere compound extremes from the Earth System perspective

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Science China Earth Sciences 2024年第2期67卷 343-374页

作者： zengchao hao Yang chen College of Water Sciences Beijing Normal UniversityBeijing100875China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing100081China

Compound extremes,whose socioeconomic and ecological impacts are severer than that caused by each event occurring in isolation,have evolved into a hot topic in Earth Science in the past *** the context of climate change,many compound extremes have exhibited increasing frequency and intensity,and shown novel fashions of combinations,posing more pressing demands and tougher challenges to scientific research and disaster prevention and *** article,via a perspective of multi-sphere interactions within the Earth System,systematically reviews the status quo,new scientific understanding,and deficiencies regarding the definition,mechanism,change,attribution,and projection of compound *** study also sorts out existing challenges and outlines a potential roadmap in advancing the study on compound extremes with respect to data requirement,mechanistic diagnosis,numerical modeling,attribution and projection,risk assessment,and adaptive *** directions of compound extremes studies and key research topics that warrant multi-disciplinary and multisectoral coordinated efforts are also *** that climate change has reshaped the type of extremes,a transformation from the traditional single-event perspective to a compound-event perspective is needed for scientific research,disaster prevention and mitigation,and climate change adaptation,calling for bottom-up innovation in research objects,ideas,and *** article will add value to promoting the research on compound extremes and interdisciplinary cooperations.

关键词： Extremes Compound extremes Climate change and risk Multi-sphere interactions

A methodology for laser tool setters calibration and its precise mathematical model

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Chinese Journal of Aeronautics 2024年第7期37卷 564-581页

作者： Tao FANG Zixi FANG ze Zhong chen Zhiyong CHANG School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China Gina Cody School of Engineering and Computer Science Concordia UniversityMontrealQuebec H3G 1M8Canada Changsha Optimum CNC Corporation Changsha 410221China Institute for Aero-engine Smart Assembly of Shaanxi Province Xi’an 710072China

On-machine tool setting is a pivotal approach in achieving intelligent manufacturing,and laser tool setters have become a crucial component of smart machine *** tool setters play a crucial role in precisely measuring the dimensions of cutting tools during the part machining process,focusing on tool length and *** a measuring instrument,the positions of the laser axis of the laser tool setter need to be accurately calibrated before ***,in actual calibration scenarios,traditional calibration methods face challenges due to installation errors in the tool setter and geometric errors in the measuring *** address this issue,this study proposes a novel calibration ***,the calibration mechanism of the laser beam axis is *** on the accurate mathematical model of the laser beam and the measuring rod,and using the polygon clipping algorithm,the mathematical mechanism of the laser tool setter’s work is ***,a novel method is introduced to calculate the compensation distance between the laser beam reference point and the rod bottom center point at each moment during ***,by utilizing the kinematic chain of the tool setter calibration system,a new calibration method is developed to accurately calibrate the position of the laser beam axis in the machine tool coordinate ***,the accuracy of the calibration method is verified through simulation experiments and calibration *** method improves the calibration accuracy of the tool setter,and the mathematical model of the laser tool setter can be extended to the measurement of tools,thereby improving the precision of tool *** research significantly improves the efficient production performance of smart machine tools.

关键词： On-machine tool setting Smart machine tools Mathematical model Calibration method Laser tool sette

SSL Depth: self-supervised learning enables 16× speedup in confocal microscopy-based 3D surface imaging [Invited]

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Chinese Optics Letters 2024年第6期22卷 3-7页

作者： ze-hao Wang Tong-Tian Weng Xiang-Dong chen Li Zhao Fang-Wen Sun CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China Anhui Golden-Shield 3D Technology Co. Ltd.Hefei 230011China

In scientific and industrial research, three-dimensional (3D) imaging, or depth measurement, is a critical tool that provides detailed insight into surface properties. Confocal microscopy, known for its precision in surface measurements, plays a key role in this field. However, 3D imaging based on confocal microscopy is often challenged by significant data requirements and slow measurement speeds. In this paper, we present a novel self-supervised learning algorithm called SSL Depth that overcomes these challenges. Specifically, our method exploits the feature learning capabilities of neural networks while avoiding the need for labeled data sets typically associated with supervised learning approaches. Through practical demonstrations on a commercially available confocal microscope, we find that our method not only maintains higher quality, but also significantly reduces the frequency of the z-axis sampling required for 3D imaging. This reduction results in a remarkable 16×measurement speed, with the potential for further acceleration in the future. Our methodological advance enables highly efficient and accurate 3D surface reconstructions, thereby expanding the potential applications of confocal microscopy in various scientific and industrial fields.

关键词： confocal microscopy 3D surface imaging self-supervised learning

Experimental Study on Vortex-Induced Vibration of Rough Risers Coupling with Interference Effect in Tandem Arrangement

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China Ocean Engineering 2024年第3期38卷 394-407页

作者： HU ze-bo LIU Zhen LI Peng GUO Hai-yan REN Xiao-hui HOU hao hao Lian-hong College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China

In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference effects on the riser,a VIV experiment of rough risers in tandem arrangement was conducted in a wave−current combined *** experiment characterized the risers’roughness by arranging different specifications of attachments on the surface of the *** rough risers with different roughness and smooth risers were arranged in tandem arrangement,with the rough risers arranged *** experimental results indicate that the suppression of the attachments on the downstream risers’vibration are more significant both in the CF and IL directions as the reduced velocity *** the downstream riser,the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced *** the upstream risers,changes in the roughness and spacing ratio have an impact on their‘lock-in’*** the roughness of downstream risers is relatively large(0.1300)and the spacing between risers is small(S/D=4.0),the reduced velocity range of‘lock-in’region in the CF direction of upstream risers is obviously expanded,and the displacement in the‘lock-in’region is severer.

关键词： marine riser vortex-induced vibration tandem arrangement roughness interference effect