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Optimization of performance of the KM2A full array using the Crab Nebula

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Chinese Physics C 2024年第6期48卷 169-178页

作者：曹臻 F.Aharonian 安琪阿西克古白云翔包逸炜 D.Bastieri 毕效军毕玉江蔡金庭曹晴曹文羽曹喆常进常劲帆陈尚明陈恩生陈亮陈林陈龙陈明君陈玛丽陈起辉陈素弘陈天禄陈阳程宁程耀东崔明阳崔树旺崔晓红崔昱东戴本忠代洪亮戴子高单增罗布 D.della Volpe 董绪强段凯凯樊军辉范一中方军方堃冯存峰封莉冯少辉丰晓婷冯有亮 S.Gabici 高博高川东高林青高启高卫高伟康葛茂茂耿利斯 G.Giacinti 龚光华苟全补顾旻皓郭福来郭晓磊郭义庆郭莹莹韩毅昂何会海贺昊宁何佳银何新波何钰 M.Heller 贺远强侯博文侯超侯贤胡红波胡铨胡世聪黄代绘黄天奇黄文俊黄性涛黄晓渊黄勇黄志成季筱璐贾焕玉贾康江琨姜晓巍姜泽军金敏康明铭柯通 D.Kuleshov.K.Kurinov 李兵兵李澄李骢李丹李飞李海波李会财李华阳李军李剑李捷李凯李文龙李文莲李秀荣李昕李一卓李哲黎卓梁恩维梁云峰林苏杰刘冰刘成刘栋刘虎刘海东刘佳刘江来刘金艳刘茂元柳若愚刘四明刘伟刘怡刘以农鲁睿罗晴吕洪魁马伯强马玲玲马欣华毛基荣闵振 W.Mitthumsiri 穆慧君南云程 A.Neronov 区子维庞彬宇 P.Pattarakijwanich 裴致远齐孟尧祁业情乔冰强秦家军 D.Ruffolo A.Sáiz D.Semikoz 邵澄宇邵琅 O.Shchegolev 盛祥东舒富文宋慧超 Yu.V.Stenkin V.Stepanov 苏扬孙秦宁孙晓娜孙志斌谭柏轩唐庆文唐泽波田文武王超王昌贝王广威王洪光王惠惠王建成汪凯王利苹王玲玉王培汉王冉王为王祥高王祥玉王阳王玉东王岩谨王忠海王仲翔王振王铮韦大明魏俊杰魏永健文韬吴超勇吴含荣武莎吴雪峰吴雨生席邵强夏捷夏君集项光漫肖迪泫肖刚辛广广辛玉良邢祎熊峥徐东莲徐仁峰徐仁新徐伟立薛良闫大海颜景志颜田杨朝文杨帆杨冯帆杨何文杨佳盈杨莉莉杨明洁杨睿智杨深邦姚玉华姚志国叶一锰尹丽巧尹娜游晓浩游智勇于艳红袁强岳华曾厚敦曾婷轩曾玮查敏张彬彬张丰张海明张恒英张建立张丽霞张力张鹏飞张佩佩张瑞张少博张少如张寿山张潇张笑鹏张云峰张毅张勇赵兵赵静赵雷赵立志赵世平郑福周斌周浩周佳能周猛周平周荣周勋秀祝成光祝凤荣朱辉朱科军左雄 LHAASO Collaboration Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Tianfu Cosmic Ray Research Center Chengdu 610000China Dublin Institute for Advanced Studies 31 Fitzwilliam Place2 DublinIreland Max-Planck-Institut for Nuclear Physics P.O.Box 10398069029 HeidelbergGermany State Key Laboratory of Particle Detection and Electronics China University of Science and Technology of China Hefei 230026China School of Physical Science and Technology&School of Information Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Hebei Normal University Shijiazhuang 050024China Key Laboratory of Dark Matter and Space Astronomy&Key Laboratory of Radio Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000TibetChina National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Physics and Astronomy(Zhuhai)&School of Physics(Guangzhou)&Sino-French Institute of Nuclear Engineering and Technology(Zhuhai) Sun Yat-sen UniversityZhuhai 519000&Guangzhou 510275China School of Physics and Astronomy Yunnan UniversityKunming 650091China Département de Physique Nucléaire et Corpusculaire Facultéde SciencesUniversitéde Genève24 Quai Ernest Ansermet1211 GenevaSwitzerland Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China APC Universit'e Paris Cit'eCNRS/IN2P3CEA/IRFUObservat

The full array of the Large High Altitude Air Shower Observatory(LHAASO)has been in operation since July *** its kilometer-square array(KM2A),we optimized the selection criteria for very high and ultrahigh energyγ-rays using data collected from August 2021 to August 2022,resulting in an improvement in significance of the detection in the Crab Nebula of approximately 15%,compared with that of previous *** the implementation of these new selection criteria,the angular resolution was also significantly improved by approximately 10%at tens of *** aspects of the full KM2A array performance,such as the pointing error,were also calibrated using the Crab *** resulting energy spectrum of the Crab Nebula in the energy range of 10-1000 TeV are well fitted by a log-parabola model,which is consistent with the previous results from LHAASO and other experiments.

关键词： γ-ray Crab Nebula significance

Repair tolerance assessment for aircraft composite structures using Bayesian updating

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Chinese Journal of Aeronautics 2024年第6期37卷 360-391页

作者： xin LI Hongfu zuo Bin YANG School of Automotive and Rail Transit Nanjing Institute of TechnologyNanjing 211167China Civil Aviation Key Laboratory of Aircraft Health Monitoring and Intelligent Maintenance College of Civil AviationNanjing University of Aeronautics and AstronauticsNanjing 211106China

Detection and repair of composite damage is crucial to ensure the safety and reliability of aircraft structures.A novel approach to quantitatively evaluate the repair tolerance of composite structures in civil aircraft based on Bayesian updating is *** method incorporates historical damage inspection data to determine the prior distribution of damage size,which is then updated with newly collected damage size data using Bayesian *** Carlo simulation is employed to investigate the probability of failure and estimate maintenance costs,considering various factors such as the frequency and timing of damage events,damage detection,structural strength,gust loads,and maintenance expenses throughout the lifecycle of composite *** and economic factors are considered to establish a lower threshold for repairs and an upper threshold for maintenance based on the occurrence of accidental impact *** of the effectiveness and feasibility of a quantitative assessment method for repair tolerance is conducted using damage statistics data from civil aircraft routes utilizing the structural skin panels of composite outer *** results demonstrate that the method proposed in conjunction with extensive simulations and full utilization of field damage inspection data can effectively simulate unexpected impact damage situations that may occur during civil aircraft service and evaluate the reliability and economic feasibility of the repair of *** research findings hold significant theoretical and practical value for the preparation of documents for continued airworthiness of composite structures,including structural repair manuals and maintenance programs.

关键词： Composite structures Repair tolerance Maintenance Bayesian updating Probability of failure

Motion-pressure coupled control and simulation of long-endurance capability for multicapsule stratospheric airships

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Chinese Journal of Aeronautics 2024年第6期37卷 137-150页

作者： Zhiguang SHI Wei HUO Zongyu zuo School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Beijing Near Space Airship Technology Development Co. LtdBeijing 100070China

The current study focuses on the motion-pressure coupled control for a multicapsule stratospheric airship and transforms the path-tracking and heading-hold control of airships into guidance tracking with a time-varying weighted sum of longitudinal and lateral velocities by the definition of compound ***,an improved nonlinear predictive control method is provided to reduce the control energy consumption by the rolling optimization of controller parameters based on finite time intervals,ensuring infinite-time path-tracking ***,combined with the proposed cyclic regulation process of safe pressure between internal and external capsules,this study can fully reflect the force-thermal coupled rule of airships under the actions of atmospheric environment and maneuvering force,while evaluating the long-endurance capability of airships under the conditions of safe superheating and *** effectiveness of the motionpressure coupled controller was verified through numerical simulations,which can overcome the influence of environmental wind and achieve a tracking effect for the desired cruise path and compound *** airspeed provided during the cyclic circadian time caused the maximum superheating of the helium controlled within 30*** helium in the internal and external capsules achieved circadian *** equivalent micropore diameter of the capsule of 5 mm can achieve 55 days of long-endurance *** controller satisfies the requirements of cruise-flight application modes for multicapsule stratospheric airships with important engineering value.

关键词： Compound speed Nonlinear predictive control Cyclic pressure regulation Long-endurance capability Stratospheric airship

A Novel Prescribed-Performance Path-Following Problem for Non-Holonomic Vehicles

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1476-1484页

作者： Zirui Chen Jingchuan Tang Zongyu zuo Seventh Research Division Beihang University(BUAA)Beijing 100191China IEEE

The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlled *** this context,a novel form of the prescribed performance guiding vector field is introduced,accompanied by a prescribed-time sliding mode con-trol ***,the interdependence among the pre-scribed parameters is *** validate the effectiveness of the proposed method,numerical simulations are presented to demonstrate the efficacy of the approach.

关键词： Guiding vector field non-holonomic vehicle path following prescribed performance sliding mode control

Single and combined effects of secondary polyethylene microplastic on the growth of Pak choi and the soil microbiome composition

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 1-12页

作者： Jiamin Hu Zhenwen xie Jiane zuo State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen518055China

It has been confirmed that microplastics(MPs)are present in the *** study simulated secondary PE-MPs via aging and mechanical processes to evaluate their effects on Pak choi(Brassica rapa L.)over 21 *** common pollutants,dichlorodiphenyltrichloroethane(DDT)and naphthalene,were used in the combined toxicity *** results indicated that the growth of Pak choi was significantly inhibited after exposure to secondary PE-MPs,and the combined effects were antagonistic,owing to the adsorption capacity of secondary PE-MPs to DDT and *** stress in Pak choi can be markedly affected,leading to oxidative damage to plant *** moisture content,soil bulk density,soil density,cation exchange capacity(CEC),and FDA hydrolase in the planted soils increased in the treated groups,and the TOC content changed *** also found that the microbial composition of the soil in the DDT and naphthalene groups showed more significant alterations than that in the other *** diversity analysis showed that species diversity increased in the combined groups but indicated a clear downward trend in the single MPs *** study suggests that secondary PE-MPs harm the growth of Pak choi and can change soil properties,revealing the harm to the ecosystem of MPs in the soil.

关键词： Secondary PE-MPs Combined effects Oxidative stress Soil properties Bacterial community

Three-dimensional limit variation analysis on the ultimate pullout capacity of the anchor cables based on the Hoek-Brown failure criterion

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Journal of Mountain Science 2024年第3期21卷 1036-1047页

作者： zuo Shi ZHAO Lianheng HU Shihong College of Civil Engineering Changsha UniversityChangsha 410022China Hunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structure Key Laboratory of Heavy-Haul Railway Engineering StructureMinistry of EducationCentral South UniversityChangsha 410075China College of Civil Engineering Central South UniversityChangsha 410075China

Only simplified two-dimensional model and a single failure mode are adopted to calculate the ultimate pullout capacity(UPC)of anchor cables in most previous *** study focuses on a more comprehensive combination failure mode that consists of bond failure of an anchorage body and failure of an anchored rock *** three-dimensional ultimate pullout capacity of the anchor cables is calculated based on the Hoek-Brown failure criterion and variation analysis *** numerical solution for the curvilinear function in fracture plane is obtained based on the finite difference theory,which more accurately reflects the failure state of the anchor cable,as opposed to that being assumed in *** results reveal that relying solely on a single failure mode for UPC calculations has limitations,as changes in parameter values not only directly impact the UPC value but also can alter the failure model and thus the calculation method.

关键词： Anchor cable Ultimate pullout capacity(UPC) Failure model Variation analysis Hoek-Brown failure criterion

An Improved UNet Lightweight Network for Semantic Segmentation of Weed Images in Corn Fields

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Computers, Materials & Continua 2024年第6期79卷 4413-4431页

作者： Yu zuo Wenwen Li School of Information and Control Engineering Jilin Institute of Chemical TechnologyJilin132022China School of Mechanical and Control Engineering Baicheng Normal UniversityBaicheng137000China

In cornfields,factors such as the similarity between corn seedlings and weeds and the blurring of plant edge details pose challenges to corn and weed *** addition,remote areas such as farmland are usually constrained by limited computational resources and limited collected ***,it becomes necessary to lighten the model to better adapt to complex cornfield scene,and make full use of the limited data *** this paper,we propose an improved image segmentation algorithm based on ***,the inverted residual structure is introduced into the contraction path to reduce the number of parameters in the training process and improve the feature extraction ability;secondly,the pyramid pooling module is introduced to enhance the network’s ability of acquiring contextual information as well as the ability of dealing with the small target loss problem;and lastly,Finally,to further enhance the segmentation capability of the model,the squeeze and excitation mechanism is introduced in the expansion *** used images of corn seedlings collected in the field and publicly available corn weed datasets to evaluate the improved *** improved model has a total parameter of 3.79 M and miou can achieve 87.9%.The fps on a single 3050 ti video card is about *** experimental results show that the network proposed in this paper can quickly segment corn weeds in a cornfield scenario with good segmentation accuracy.

关键词： Semantic segmentation deep learning UNet pyramid pooling module

A Dual-Task Learning Approach for Bearing Anomaly Detection and State Evaluation of Safe Region

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 229-241页

作者： Yuhua Yin Zhiliang Liu Bin Guo Mingjian zuo School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Qingdao International Academician Park Research Institute Qingdao 266041China

Predictive maintenance has emerged as an effective tool for curbing maintenance costs,yet prevailing research predominantly concentrates on the abnormal *** the ostensibly stable healthy phase,the reliance on anomaly detection to preempt equipment malfunctions faces the challenge of sudden anomaly *** address this challenge,this paper proposes a dual-task learning approach for bearing anomaly detection and state evaluation of safe *** proposed method transforms the execution of the two tasks into an optimization issue of the hypersphere *** leveraging the monotonicity and distinguishability pertinent to the tasks as the foundation for optimization,it reconstructs the SVDD model to ensure equilibrium in the model’s performance across the two *** experiments verify the proposed method’s effectiveness,which is interpreted from the perspectives of parameter adjustment and enveloping *** the meantime,experimental results also show two deficiencies in anomaly detection accuracy and state evaluation *** theoretical analysis inspires us to focus on feature extraction and data collection to achieve *** proposed method lays the foundation for realizing predictive maintenance in a healthy stage by improving condition awareness in safe regions.

关键词： Bearing condition monitoring Anomaly detection Safe region Support vector data description

Multi-circular formation control with reinforced transient profiles for nonholonomic vehicles:A path-following framework

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Defence Technology（防务技术） 2024年第1期31卷 278-287页

作者： Jintao Zhang xingling Shao Wendong Zhang Zongyu zuo School of Instrument and Electronics North University of ChinaTaiyuan 030051China State Key Laboratory of Dynamic Measurement Technology North University of ChinaTaiyuan 030051China Seventh Research Division School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100191China

This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the feature of spatial-temporal decoupling is devised for a group of vehicles guided by a virtual leader evolving along an implicit path,which allows for a circumnavigation on multiple circles with an anticipant angular *** addition,notice that it typically imposes a stringent time constraint on time-sensitive enclosing scenarios,hence an improved prescribed performance control(IPPC)using novel tighter behavior boundaries is presented to enhance transient capabilities with an ensured appointed-time convergence free from any *** significant merits are that coordinated circumnavigation along different circles can be realized via executing geometric and dynamic assignments independently with modified transient ***,all variables existing in the entire system are analyzed to be *** and experimental results are provided to validate the utility of suggested solution.

关键词： Multi-circular formation Reinforced transient profiles Nonholonomic vehicles Path following