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Anisotropic magnetism and band evolution induced by ferromagnetic phase transition in titanium-based kagome ferromagnet SmTi_3Bi_4

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science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 137-145页

作者： Zhe Zheng Long Chen Xuecong Ji Ying Zhou Gexing Qu Mingzhe Hu Yaobo Huang Hongming Weng Tian Qian Gang Wang Beijing national Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of sciences Beijing 100049China school of Physics and Engineering Henan University of Science and TechnologyLuoyang 471023China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China Songshan Lake Materials Laboratory Dongguan 523808China CAS Center for Excellence in Topological Quantum Computation Chinese Academy of SciencesBeijing 100190China

Kagome magnets with diverse topological quantum responses are crucial for next-generation topological *** anisotropic magnetism and band evolution induced by ferromagnetic phase transition(FMPT)is reported in a newly discovered titanium-based kagome ferromagnet Sm Ti3Bi4,which features a distorted Ti kagome lattice and Sm atomic zig-zag ***-dependent resistivity,heat capacity,and magnetic susceptibility reveal a ferromagnetic ordering temperature Tc of23.2 K.A large magnetic anisotropy,observed by applying the magnetic field along three crystallographic axes,identifies the b axis as the easy ***-resolved photoemission spectroscopy with first-principles calculations unveils the characteristic kagome motif,including the Dirac point at the Fermi level and multiple van Hove ***,a band splitting and gap closing attributed to FMPT is observed,originating from the exchange coupling between Sm 4 f local moments and itinerant electrons of the kagome Ti atoms,as well as the time-reversal symmetry breaking induced by the long-range ferromagnetic *** the large in-plane magnetization and the evolution of electronic structure under the influence of ferromagnetic ordering,such materials promise to be a new platform for exploring the intricate electronic properties and magnetic phases based on the kagome lattice.

关键词： kagome lattice anisotropic magnetism band splitting ferromagnetic phase transition ARPES

The Adjustment Analysis Method of the Active Surface Antenna Based on Convolutional Neural Network

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Research in Astronomy and Astrophysics 2024年第6期24卷 294-306页

作者： You Ban Shang Shi Na Wang Qian Xu Shufei Feng school of Mechanical Engineering Xinjiang UniversityUrumqi 830017China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China school of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China

Active surface technique is one of the key technologies to ensure the reflector accuracy of the millimeter/submillimeter wave large reflector *** antenna is complex,large-scale,and high-precision equipment,and its active surfaces are affected by various factors that are difficult to comprehensively deal *** this paper,based on the advantage of the deep learning method that can be improved through data learning,we propose the active adjustment value analysis method of large reflector antenna based on deep *** method constructs a neural network model for antenna active adjustment analysis in view of the fact that a large reflector antenna consists of multiple panels spliced *** on the constraint that a single actuator has to support multiple panels(usually 4),an autonomously learned neural network emphasis layer module is designed to enhance the adaptability of the active adjustment neural network *** classical 8-meter antenna is used as a case study,the actuators have a mean adjustment error of 0.00252 mm,and the corresponding antenna surface error is0.00523 *** active adjustment result shows the effectiveness of the method in this paper.

关键词： techniques:radar astronomy telescopes methods:analytical methods:numerical

AI Fairness-From Machine Learning to Federated Learning

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Computer Modeling in Engineering & sciences 2024年第5期139卷 1203-1215页

作者： Lalit Mohan Patnaik Wenfeng Wang Consciousness Studies Program School of HumanitiesNational Institute of Advanced StudiesBangalore560012India Research Institute of Intelligent Engineering and Data Applications Shanghai Institute of TechnologyShanghai201418China Research Center of Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi830011China Applied Nonlinear science Lab Anand International College of EngineeringJaipur391320India London Institute of technology The ASE-London CTI of SCOLondonCR26EQUK Sino-Indian Joint Research Center of AI and Robotics The IMT InstituteBhubaneswar752054India

This article reviews the theory of fairness in AI-frommachine learning to federated learning,where the constraints on precision AI fairness and perspective solutions are also *** a reliable and quantitative evaluation of AI fairness,many associated concepts have been proposed,formulated and ***,the inexplicability of machine learning systems makes it almost impossible to include all necessary details in the modelling stage to ensure *** privacy worries induce the data unfairness and hence,the biases in the datasets for evaluating AI fairness are *** imbalance between algorithms’utility and humanization has further reinforced *** for federated learning systems,these constraints on precision AI fairness still *** solution is to reconcile the federated learning processes and reduce biases and imbalances accordingly.

关键词： Formulation evaluation classification constraints imbalance biases

Instability mechanism of mining roadway passing through fault at different angles in kilometre-deep mine and control measures of roof cutting and NPR cables

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Journal of Mountain science 2024年第1期21卷 236-251页

作者： SUN Xiaoming WANG Jian ZHAO Wenchao MING Jiang ZHANG Yong LI Zhihu MIAO Chengyu GUO Zhibiao HE Manchao State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China school of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China

The angle α between the fault strike and the axial direction of the roadway produces different damage characteristics. In this paper, the research methodology includes theoretical analyses, numerical simulations and field experiments in the context of the Daqiang coal mine located in Shenyang, China. The stability control countermeasure of "pre-splitting cutting roof + NPR anchor cable"(PSCR-NPR) is simultaneously proposed. According to the different deformation characteristics of the roadway, the faults are innovatively classified into three types, with α of type I being 0°-30°, α of type II being 30°-60°, and α of type III being 60°-90°. The full-cycle stress evolution paths during mining roadway traverses across different types of faults are investigated by numerical simulation. Different pinch angles α lead to high stress concentration areas at different locations in the surrounding rock. The non-uniform stress field formed in the shallow surrounding rock is an important reason for the instability of the roadway. The pre-cracked cut top shifted the high stress region to the deep rock mass and formed a low stress region in the shallow rock mass. The high prestressing NPR anchor cable transforms the non-uniform stress field of the shallow surrounding rock into a uniform stress field. PSCR-NPR is applied in the fault-through roadway of Daqiang mine. The low stress area of the surrounding rock was enlarged by 3-7 times, and the cumulative convergence was reduced by 45%-50%. It provides a reference for the stability control of the deep fault-through mining roadway.

关键词： Kilometre-deep mine Fault Mining roadway Failure mechanism Pre-splitting cutting roof High pre-stress NPR anchor cable

Stress-corrosion coupled damage localization induced by secondary phases in bio-degradable Mg alloys:phase-field modeling

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Journal of Magnesium and Alloys 2024年第1期12卷 361-383页

作者： Chao Xie Shijie Bai Xiao Liu Minghua Zhang Jianke Du The Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211P.R.China Key Laboratory of High Temperature Wear Resistant Materials Preparation technology of Hunan Province Hunan University of Science and TechnologyXiangtan 411201P.R.China

In this study,a phase-field scheme that rigorously obeys conservation laws and irreversible thermodynamics is developed for modeling stress-corrosion coupled damage(SCCD).The coupling constitutive relationships of the deformation,phase-field damage,mass transfer,and electrostatic field are derived from the entropy *** SCCD localization induced by secondary phases in Mg is numerically simulated using the implicit iterative algorithm of the self-defined finite *** quantitative evaluation of the SCCD of a C-ring is in good agreement with the experimental *** capture the damage localization,a micro-galvanic corrosion domain is defined,and the buffering effect on charge migration is *** cases are investigated to reveal the effect of localization on corrosion acceleration and provide guidance for the design for resistance to SCCD at the crystal scale.

关键词： Phase field Mg alloys Stress-corrosion coupled damage Damage localization Finite element method

Cosmological constraints on neutrino mass within consistent cosmological models

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Chinese Physics C 2024年第6期48卷 191-197页

作者：庞业煌张雪黄庆国 school of Fundamental Physics and Mathematical sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China school of Physical sciences University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

Recently,the emergence of cosmological tension has raised doubts about the consistency of the ACDM *** constrain the neutrino mass within a consistent cosmological framework,we investigate three massive neutrinos with normal hierarchy(NH)and inverted hierarchy(IH)in both the axion-like early dark energy(AxiEDE)and AdS-EDE *** use joint datasets including the cosmic microwave background power spectrum from Plaanck 2018,Pantheon of type la supernova,baryon acoustic oscillation,and H0data from *** the vAxi-EDE model,we obtain∑m_(v),NH<0.152 eV and∑m_(v),IH<0.178 eV,whereas for the vAdS-EDE model,we find∑m_(v),NH<0.135 eV and∑m_(v),IH<0.167 *** results exhibit a preference for NH in both the vAxi-EDE and vAdS-EDE models.

关键词： neutrino mass cosmological tension early dark energy

Green synthesis of ZSM-5 using silica fume and catalytic co-cracking of lignin and plastics for production of monocyclic aromatics

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Chinese Journal of Chemical Engineering 2024年第1期65卷 92-105页

作者： Hongbing Fu Yufei Gu Tianhua Gao Fuwei Li Hengshuo Gu Hucheng Ge Yuke Liu Zhixia Li Hongfei Lin Jiangfei Cao school of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China Guangxi Bossco Environmental Protection technology Co. Ltd.Nanning 530007China school of Environmental and Chemical Engineering Zhaoqing UniversityZhaoqing 526000China

ZSM-5 with hierarchical pore structure was synthesized by a simple two-step hydrothermal crystallization from silica fume without using any organic ammonium *** synthesized ZSM-5 were oval shaped particles with a particle size about 2.0 μm and weak acid-dominated with proper Brønsted(B)and Lewis(L)acid *** ZSM-5 was used for catalytic co-cracking of n-octane and guaiacol,lowdensity polyethylene(LDPE)and alkali lignin(AL)to enhance the production of benzene,toluene,ethylbenzene and xylene(BTEX).The most significant synergistic effect occurred at n-octane/guaiacol at 1:1 and LDPE/AL at 1:3,under the condition,the achieved BTEX selectivity were 24%and 33%(mass)higher than the calculated values(weighted average).The highest BTEX selectivity reached 88.5%,which was 3.7%and 54.2%higher than those from individual cracking LDPE and *** synthesized ZSM-5 exhibited superior catalytic performance compared to the commercial ZSM-5,indicating potential application prospect.

关键词： Silica fume ZSM-5 Catalytic co-cracking Plastics Lignin

A lunar time scale from the perspective of the Moon’s dynamic evolution

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science China Earth sciences 2024年第1期67卷 234-251页

作者： Dijun GUO Jianzhong LIU James WHEAD Fuqin ZHANG Zongcheng LING Shengbo CHEN Jianping CHEN Xiaozhong DING Jinzhu JI Ziyuan OUYANG State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Center for Lunar and Planetary sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Department of Earth Environmental and Planetary SciencesBrown UniversityProvidence RI 02912USA Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China College of Geoexploration science and technology Jilin UniversityChangchun 130026China school of Earth sciences and Resources China University of GeosciencesBeijing 100083China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China school of Resources and Environmental Engineering Inner Mongolia University of TechnologyHohhot 010051China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China

A geologic time scale is a chronological system that separates the geological strata of a planetary body into different units in temporal sequence and shows its progressive *** time scale of the Moon was established a half-century ago during the telescopic-early Apollo exploration era,using data with limited spatial coverage and *** past decades have seen a wide array of studies,which have significantly extended our understanding of global lunar geologic *** on a comprehensive review of lunar evolution with respect to the dynamical changes,we propose two major updates to the current lunar time scale paradigm to include the evolution of both endogenic and exogenic dynamic forces now known to have influenced early lunar ***,based on the temporal interplay of exogenic and endogenic processes in altering the Moon,we defined three Eon/Eonothem-level units to represent three dynamical evolutionary ***,the pre-Nectarian System is redefined and divided as the magma ocean-era Magma-oceanian System and the following Aitkenian System beginning with the South Pole-Aitken *** ejecta of this basin,Das Formation,was deposited on the primordial lunar crust as the oldest stratum produced from exogenic *** updated lunar time scale,facilitated by the post-Apollo exploration and research advances,provides an integrated framework to depict the evolution of the Moon and has important implications for the geologic study of other terrestrial planets.

关键词： The Moon Geologic time scale Evolution history Endogenic process Exogenic process

Optimization of Center of Gravity Position and Anti-Wave Plate Angle of Amphibious Unmanned Vehicle Based on Orthogonal Experimental Method

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Computer Modeling in Engineering & sciences 2024年第5期139卷 2027-2041页

作者： Deyong Shang Xi Zhang Fengqi Liang Chunde Zhai Hang Yang Yanqi Niu school of Mechanical Electronic&Information EngineeringChina University of Mining and Technology(Beijing)Beijing100083China Institute of Intelligent Mining&Robotics China University of Mining and Technology(Beijing)Beijing100083China

When the amphibious vehicle navigates in water,the angle of the anti-wave plate and the position of the center of gravity greatly influence the navigation *** the relevant research on reducing the navigation resistance of amphibious vehicles by adjusting the angle of the anti-wave plate,there is a lack of scientific selection of parameters and reasonable research of simulation results by using mathematical methods,and the influence of the center of gravity position on navigation characteristics is not considered at the same *** study the influence of the combinations of the angle of the anti-wave plate and the position of the center of gravity on the resistance reduction characteristics,a numerical calculation model of the amphibious unmanned vehicle was established by using the theory of computational fluid dynamics,and the experimental data verified the correctness of the numerical *** on this numerical model,the navigation characteristics of the amphibious unmanned vehicle were studied when the center of gravity was located at different positions,and the orthogonal experimental design method was used to optimize the parameters of the angle of the anti-wave plate and the position of the center of *** results show that through the parameter optimization analysis based on the orthogonal experimental method,the combination of the optimal angle of the anti-wave plate and the position of the center of gravity is *** the numerical simulation result of resistance is consistent with the predicted optimal *** with the maximum navigational resistance,the parameter optimization reduces the navigational resistance of the amphibious unmanned vehicle by 24%.

关键词： Amphibious unmanned vehicle orthogonal experimental design anti-wave plate center of gravity resistance characteristic