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Anomalous open orbits in Hofstadter spectrum of Chern insulator

CCAST“放射性束物理”研讨会

作者： X.J.Xu. J Powell R.Josten C.A Donahue R.f.fairchild f.q.guo P.E Jaustein R,M.Larimer C,M Lyneis P.Mcnahan D.M Moltz E,B Norman J P ONeil M.W.Rowe H.f.Vanbrocklin D.Wutte Z.q.Xie J,Cemy Lawrence Berkeley National Laborqtory USA Institute of Modem Physics Chinese Academy of Sciences Brooljanven National Laboratory USA

＜正＞BEARS, or Berkeley Experiments with Accelerated Radioactive Species, is aninitiative to develop a radioactive ion-beam capability at Lawrence Berkeley NationalLaboratory. The basic concept for BEANS involves the coupling of radioisotopeproduction at an existing medical cyclotron with post-acceleration by the 88”cyclotron. These accelerators are separated by distance of about 350 *** be transported between the two via a gas-jet capillary（fig.1）

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Science China(Physics,Mechanics & Astronomy) 2025年第3期Mechanics & Astronomy) .卷 143-148页

作者： Haijiao Ji Peng Zhou Noah f.q.Yuan Hua Jiang Haiwen Liu X.C.Xie Center for Advanced quantum Studies Department of Physics Beijing Normal University Tsung-Dao Lee Institute Shanghai Jiao Tong University Department of Mathematics UC Berkeley Institute for Nanoelectronic Devices and quantum Computing Fudan University International Center for quantum Materials School of Physics Peking University Hefei National Laboratory

The nontrivial band topology of Chern insulator can enrich the content of its Hofstadter butterfly spectra, which is closely related to recent experiments in twisted bilayer graphene and cold atom systems. We investigate the Hofstadter spectrum for various models of Chern insulators under a rational flux φ0/q, here φ0=h/e and q being an integer. We find the number of splitting subbands is |q-C| with C denoting the Chern number of parent band. Importantly, anomalous open-orbital subbands with Chern numbers q-1 and-q-1 emerge unexpectedly, which are beyond the parameter window（-q/2, q/2） of the Diophantine equation studied by Thouless-Kohmoto-Nightingale-den Nijs [Phys. Rev. Lett. 49, 405（1982）]. The emergence of anomalous open orbits can be traced by analyzing the evolution of the Hofstadter spectrum, identifying as a new type of topological phase transition. These novel findings not only pinpoint the peculiar Hofstadter spectrum of Chern insulator, but also provide routes to study exotic characteristics beyond the Landau level physics.

关键词： Hofstadter spectrum topological phase transition open orbit

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Anomaly Detection of Controllable Electric Vehicles through Node Equation against Aggregation Attack

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Computers, Materials & Continua 2025年第1期82卷 427-442页

作者： Jing guo Ziying Wang Yajuan guo Haitao Jiang State Grid Jiangsu Electric Power Co. Ltd.Research InstituteState Grid Corporation of ChinaNanjing211100China

The rapid proliferation of electric vehicle(EV)charging infrastructure introduces critical cybersecurity vulnerabilities to power grids *** study presents an innovative anomaly detection framework for EV charging stations,addressing the unique challenges posed by third-party aggregation *** approach integrates node equations-based on the parameter identification with a novel deep learning model,xDeepCIN,to detect abnormal data reporting indicative of aggregation *** employ a graph-theoretic approach to model EV charging networks and utilize Markov Chain Monte Carlo techniques for accurate parameter *** xDeepCIN model,incorporating a Compressed Interaction Network,has the ability to capture complex feature interactions in sparse,high-dimensional charging *** results on both proprietary and public datasets demonstrate significant improvements in anomaly detection performance,with f1-scores increasing by up to 32.3%for specific anomaly types compared to traditional methods,such as wide&deep and DeepfM(factorization-Machine).Our framework exhibits robust scalability,effectively handling networks ranging from 8 to 85 charging ***,we achieve real-time monitoring capabilities,with parameter identification completing within seconds for networks up to 1000 *** research contributes to enhancing the security and reliability of renewable energy systems against evolving cyber threats,offering a comprehensive solution for safeguarding the rapidly expanding EV charging infrastructure.

关键词： Anomaly detection electric vehicle aggregation attack deep cross-network

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng Wang qinyi guo Bin Hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

Geometric-like imaginarity:quantification and state conversion

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 13-22页

作者： Meng-Li guo Bo Li Shao-Ming fei School of Science East China University of TechnologyNanchang 330006China School of Computer and Computing Science Hangzhou City University Hangzhou 310015China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

from the perspective of resource-theoretic approach,this study explores the quantification of imaginary in quantum *** propose a well defined measure of imaginarity,the geometric-like measure of *** with the usual geometric imaginarity measure,this geometric-like measure of imaginarity exhibits smaller decay difference under quantum noisy channels and higher *** applications,we show that both the optimal probability of state transformations from a pure state to an arbitrary mixed state via real operations,and the maximal probability of stochastic-approximate state transformations from a pure state to an arbitrary mixed state via real operations with a given fidelity f,are given by the geometric-like measure of imaginarity.

关键词： quantum resource theory imaginarity geometric-like channels state transformations

Regulating local electron transfer environment of covalent triazine frameworks through f,N co-modification towards optimized oxygen reduction reaction

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Chinese Chemical Letters 2025年第1期36卷 344-348页

作者： quanyou guo Yue Yang Tingting Hu Hongqi Chu Lijun Liao Xuepeng Wang Zhenzi Li Liping guo Wei Zhou Shandong Provincial Key Laboratory of Molecular Engineering School of Chemistry and Chemical EngineeringQilu University of Technology(Shandong Academy of Sciences)Ji’nan 250353China

The high conductivity of electrocatalyst can eliminate the Schottky energy barrier at the interface of heterogeneous phases during an electrocatalytic reaction and accelerate the rapid electron transfer to the catalytic active ***,the electronic conductivity is a vital parameter for oxygen reduction reaction(ORR).Covalent triazine frameworks(CTfs)have shown great potential application as electrocatalysts in ORR with a merit of the diverse building ***,the intrinsic low conductivity and high impedance of CTfs could be significant setbacks in electrocatalytic ***,CTfs were constructed by introducing f and N co-modification for efficient 2e^(-)*** with the pristine CTf,the co-presence of f,N could increase the conductivity obviously by *** a result,f-N-CTf exhibits enhanced catalytic performance of H_(2)O_(2)generation and selectivity towards reaction *** work reveals the importance of conductivity optimization for CTfs and provides guidance for designing high conductivity non-metallic organic semiconductor catalysts for 2e^(-)ORR.

关键词： Covalent triazine frameworks Conductivity Co-modification Electrocatalysis Oxygen reduction reaction

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong Hou Shuo Zhang Jie Dang Jia guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(fTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(q^(3))/X_(q^(2))(X_(q^(i))is the molar fraction of q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

Yielding performance of compact yielding anchor cable in working state:Analytical theory and experimental evaluation of yielding resistance enhancement effect

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International Journal of Mining Science and Technology 2025年第1期35卷 101-120页

作者： Zhenyu Wang Bo Wang Xinxin guo Jinjin Li Zhenwang Ma State Key Laboratory of Intelligent Geotechnics and Tunnelling Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Geohazard Prevention and Geoenvironmental Protection Chengdu University of TechnologyChengdu 610059China China Design Group Co. Ltd.Nanjing 210001China

To elucidate the yielding performance of compact yielding anchor cables in working state,a yielding mechanical model incorporating extrusion friction and fastening rotation under confining pressure is *** yielding resistance enhancement effect(ω)caused by working environment constraints is evaluated through multi-layer composite sleeve hole expansion analysis,forming a theoretical framework for calculating the working yielding *** and in-situ pull-out tests are conducted to determine the yielding performance and validate the analytical *** main conclusions are:(1)Yielding force and energy-release capacity increase withω,significantly outperforming the unconfined state.(2)In-situ tests under varying rockmass and geostress conditions(f1–f3)determine the yielding force increases to 183.4–290.1,204.0–290.8,and 235.0–327.1 kN.(3)The slight deviation(–12.5%to 6.2%)between the theoretical and measured yielding force confirms that the analytical theory effectively describes the working yielding performance.(4)ωincreases with higher geostress and improved rock mechanical properties,with initial geostress(σ_(0))and elastic modulus of surrounding rock(E_(3))identified as critical parameters.

关键词： Compact yielding anchor cables Working state Yielding resistance enhancement effect Yielding mechanical performance Pull-out test

Deep reinforcement learning based integrated evasion and impact hierarchical intelligent policy of exo-atmospheric vehicles

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Chinese Journal of Aeronautics 2025年第1期38卷 409-426页

作者： Leliang REN Weilin guo Yong XIAN Zhenyu LIU Daqiao ZHANG Shaopeng LI Xi’an Research Institute of High Technology Xi’an 710025China China Xi’an Satellite Control Center Xi’an710043China Department of Automation Tsinghua UniversityBeijing 100084China

Exo-atmospheric vehicles are constrained by limited maneuverability,which leads to the contradiction between evasive maneuver and precision *** address the problem of Integrated Evasion and Impact(IEI)decision under multi-constraint conditions,a hierarchical intelligent decision-making method based on Deep Reinforcement Learning(DRL)was ***,an intelligent decision-making framework of“DRL evasion decision”+“impact prediction guidance decision”was established:it takes the impact point deviation correction ability as the constraint and the maximum miss distance as the objective,and effectively solves the problem of poor decisionmaking effect caused by the large IEI decision ***,to solve the sparse reward problem faced by evasion decision-making,a hierarchical decision-making method consisting of maneuver timing decision and maneuver duration decision was proposed,and the corresponding Markov Decision Process(MDP)was designed.A detailed simulation experiment was designed to analyze the advantages and computational complexity of the proposed *** results show that the proposed model has good performance and low computational resource *** minimum miss distance is 21.3 m under the condition of guaranteeing the impact point accuracy,and the single decision-making time is 4.086 ms on an STM32f407 single-chip microcomputer,which has engineering application value.

关键词： Exo-atmospheric vehicle Integrated evasion and impact Deep reinforcement learning Hierarchical intelligent policy Single-chip microcomputer Miss distance