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Extended Dissipaton Theory for Higher-Order Bath Couplings and Application to Non-Condon Spectroscopy with Anharmonicity
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作者 Zi-Fan Zhu Yu Su +2 位作者 Yao Wang Rui-Xue Xu YiJing Yan 《Chinese Journal of Chemical Physics》 2026年第1期67-72,I0043,共7页
In this work,we develop an extended dissipaton theory that generalizes the environmental couplings beyond the conventional linear and quadratic forms,enabling the treatment of ar-bitrary order of bath couplings.Ap-ply... In this work,we develop an extended dissipaton theory that generalizes the environmental couplings beyond the conventional linear and quadratic forms,enabling the treatment of ar-bitrary order of bath couplings.Ap-plying this theoretical framework to the condensed-phase non-Condon spectroscopy,we demonstrate the in-terplay of anharmonicity,non-Con-don and solvent effects on optical spectra,where the higher-order cou-plings arise from the anharmonicity of nuclear potential surface of the excited state.Precise simulations are carried out with high efficiency on linear absorption spectra involving the above mentioned correlated effects.We exhibit how an anharmonic potential modulates the vibronic feature,offering insights into the role of nonlinear environmental couplings in spectroscopic signatures and exemplifying the success of the extended dissipaton formalism as an exact and efficient method for higher-or-der bath couplings. 展开更多
关键词 Quantum dissipation higher-order nonlinear bath couplings Anharmonic and non-Gaussian bath Non-Condon spectroscopy
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A Chinese Expert Consensus on the Artificial Intelligence Proficiency of Medical Students:Competencies and the Multi-Modal Assessment
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作者 Mengchun Gong Jiao Li +8 位作者 Yonghui Ma Bo Jin Wei Chen Yan Hou Li Hong Tianwen Lai Bohan Zhang Ge Wu Zhirong Zeng 《Health Care Science》 2026年第1期49-57,共9页
Background:Artificial intelligence(AI)is transforming healthcare,demanding reevaluation of medical education.China's“New Medical Education”initiative urgently requires a standardized AI literacy framework for me... Background:Artificial intelligence(AI)is transforming healthcare,demanding reevaluation of medical education.China's“New Medical Education”initiative urgently requires a standardized AI literacy framework for medical students to address fragmented standards,rapid technological evolution,and insufficient localized ethical norms.Objective:To establish a Chinese expert consensus defining core AI competencies and a multi-modal assessment framework for medical students.Methods:A multidisciplinary(including medical education,clinical medicine,medical AI,public health,and medical ethics)expert group(n=32)developed an initial competency list based on the“Knowledge-Skills-Attitude”Medical Competency Model.Two Delphi rounds(100%response rate;consensus threshold:mean≥4.0,CV≤0.25)refined the framework.Core competencies were prioritized via Analytic Hierarchy Process(AHP).The final consensus document was established after multiple expert group meetings.Results:The consensus defines AI literacy for medical students as a comprehensive attribute for integrating AI into profes-sional knowledge,clinical practice,research,and health management.It comprises a 21-item Competencies of AI Proficiency(CAIP)list across knowledge(eight indicators),skills(seven indicators),and attitude(six indicators)dimensions.Key com-petencies prioritized include understanding AI's role in multidisciplinary knowledge integration(CAIP3),identifying AI output biases(CAIP4),understanding health data governance(CAIP2),maintaining physician-led AI-assisted diagnosis(CAIP16),and identifying AI diagnostic biases(CAIP12).A multi-modal assessment framework is recommended,including paper-based/computerized tests for knowledge,situational judgment tests(SJTs)for attitudes,and objective structured clinical examinations(OSCEs)with a specific“AI Clinical Decision Conflict Scoring Scale”for skills.A multi-stage dynamic assessment system(“Pre-enrollment-Pre-clinical-Post-clinical”)is proposed for longitudinal tracking.Educational integration pathways emphasize embedding AI literacy modularly from early undergraduate years,constructing an integrated curriculum covering fundamental principles,advanced large model applications(e.g.,prompt engineering,agent development),and ethical considerations,supported by a"digital twin hospital platform."Conclusion:This consensus provides authoritative,China-specific guidance for defining and assessing medical students'AI literacy,adhering to national policies and regulations.It offers a core action framework for optimizing AI integration into medical education,fostering future healthcare professionals proficient in both AI technology and medical humanism,with a commitment to dynamic updating to adapt to evolving AI advancements. 展开更多
关键词 AI proficiency artificial intelligence(AI) ASSESSMENT competency framework medical education
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Optimal Synchronization of Higher-Order Dynamical Networks 被引量:2
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作者 Guanrong CHEN 《Artificial Intelligence Science and Engineering》 2025年第1期31-36,共6页
This article briefly reviews the topic of complex network synchronization,with its graph-theoretic criterion,showing that the homogeneous and symmetrical network structures are essential for optimal synchronization.Fu... This article briefly reviews the topic of complex network synchronization,with its graph-theoretic criterion,showing that the homogeneous and symmetrical network structures are essential for optimal synchronization.Furthermore,it briefly reviews the notion of higher-order network topologies and shows their promising potential in application to evaluating the optimality of network synchronizability. 展开更多
关键词 complex network SYNCHRONIZATION optimal synchronizability SIMPLEX higher-order topology
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A New Technique for Constructing Higher-order Iterative Methods to Solve Nonlinear Systems
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作者 XIAO Xiaoyong 《应用数学》 北大核心 2025年第3期762-774,共13页
In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introduc... In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introducing only one additional evaluation of the function in each step.Furthermore,some new efficient methods with a higher-order of convergence are obtained by using only a single matrix inversion in each iteration.Analyses of convergence properties and computational efficiency of these new methods are made and testified by several numerical problems.By comparison,the new schemes are more efficient than the corresponding existing ones,particularly for large problem sizes. 展开更多
关键词 Systems of nonlinear equation Order of convergence higher-order method Extended Newton iteration Computational efficiency
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Higher-order optimality conditions for multiobjective optimization through a new type of directional derivatives
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作者 HUANG Zheng-gang 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期543-557,共15页
This paper deals with extensions of higher-order optimality conditions for scalar optimization to multiobjective optimization.A type of directional derivatives for a multiobjective function is proposed,and with this n... This paper deals with extensions of higher-order optimality conditions for scalar optimization to multiobjective optimization.A type of directional derivatives for a multiobjective function is proposed,and with this notion characterizations of strict local minima of order k for a multiobjective optimization problem with a nonempty set constraint are established,generalizing the corresponding scalar case obtained by Studniarski[3].Also necessary not sufficient and sufficient not necessary optimality conditions for this minima are derived based on our directional derivatives,which are generalizations of some existing scalar results and equivalent to some existing multiobjective ones.Many examples are given to illustrate them there. 展开更多
关键词 strict local minima of order k multiobjective optimization higher-order optimality conditions higher-order directional derivatives
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Explosive information spreading in higher-order networks:Effect of social reinforcement
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作者 Yu Zhou Yingpeng Liu +4 位作者 Liang Yuan Youhao Zhuo Kesheng Xu Jiao Wu Muhua Zheng 《Chinese Physics B》 2025年第3期196-202,共7页
Information spreading has been investigated for many years,but the mechanism of why the information explosively catches on overnight is still under debate.This explosive spreading phenomenon was usually considered dri... Information spreading has been investigated for many years,but the mechanism of why the information explosively catches on overnight is still under debate.This explosive spreading phenomenon was usually considered driven separately by social reinforcement or higher-order interactions.However,due to the limitations of empirical data and theoretical analysis,how the higher-order network structure affects the explosive information spreading under the role of social reinforcement has not been fully explored.In this work,we propose an information-spreading model by considering the social reinforcement in real and synthetic higher-order networks,describable as hypergraphs.Depending on the average group size(hyperedge cardinality)and node membership(hyperdegree),we observe two different spreading behaviors:(i)The spreading progress is not sensitive to social reinforcement,resulting in the information localized in a small part of nodes;(ii)a strong social reinforcement will promote the large-scale spread of information and induce an explosive transition.Moreover,a large average group size and membership would be beneficial to the appearance of the explosive transition.Further,we display that the heterogeneity of the node membership and group size distributions benefit the information spreading.Finally,we extend the group-based approximate master equations to verify the simulation results.Our findings may help us to comprehend the rapidly information-spreading phenomenon in modern society. 展开更多
关键词 explosive information spreading social reinforcement higher-order interactions complex network
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Corneal higher-order aberrations following small incision lenticule extraction for high myopic astigmatism correction
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作者 Yin Liu Cheng Hu +3 位作者 Juan Yu Nian Xiang Bo Zeng Wen-Shan Jiang 《International Journal of Ophthalmology(English edition)》 2025年第7期1349-1356,共8页
AIM:To compare the visual outcomes and corneal higherorder aberrations(HOAs)of patients with high or low myopic astigmatism after small incision lenticule extraction(SMILE).METHODS:A total of 157 eyes of 157 patients ... AIM:To compare the visual outcomes and corneal higherorder aberrations(HOAs)of patients with high or low myopic astigmatism after small incision lenticule extraction(SMILE).METHODS:A total of 157 eyes of 157 patients who underwent SMILE were included in this retrospective,nonrandomized,comparative study.All the eyes which were with the rule astigmatism were divided into high astigmatism group(HAG;astigmatism≤-2.00 D,73 eyes)and low astigmatism group(LAG;astigmatism≥-1.00 D,84 eyes).Visual and refractive examinations were performed,HOAs of the anterior surface,posterior surface,and total cornea of the eyes were evaluated preoperatively and 6mo postoperatively.RESULTS:At the postoperative 6-month follow-up,uncorrected distance visual acuity of 20/20 or better was achieved in 97%and 100%eyes in HAG and LAG respectively and 74%and 100%eyes were within-0.50 D.Vector analysis revealed no significant differences in the correction index(P=0.066),angle of error(P=0.091)or flattening index(P=0.987)between two groups.The magnitude of error was-0.37±0.31 D in HAG and-0.04±0.19 D in LAG(P<0.001).Index of success(IOS)was 0.22±0.09 in the HAG and 0.50±0.46 in the LAG(P<0.001).HOAs of most anterior,posterior and total cornea significantly increased after SMILE,especially the spherical aberration and coma.For HAG,the SMILE procedure induced significantly higher anterior,posterior and total cornea horizontal coma and total corneal total HOAs compared with LAG(P<0.001)and these surgically induced HOAs predominantly originated from the anterior surface of the cornea.CONCLUSION:SMILE surgery induces more HOAs and a mild under-correction of astigmatism in eyes with high astigmatism.The increment in HOAs after SMILE is related to preoperative astigmatism. 展开更多
关键词 small incision lenticule extraction high astigmatism higher-order aberrations MYOPIA
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Development and verification of the higher-order mode neutron flux calculation code HARMONY2.0
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作者 Er-Pin Zhang Zi-Ning Ni +3 位作者 Nian-Biao Deng Jin-Sen Xie Yong Liu Tao Yu 《Nuclear Science and Techniques》 2025年第1期207-225,共19页
Higher-order modes of the neutron diffusion/transport equation can be used to study the temporal behavior of nuclear reactors and can be applied in modal analysis, transient analysis, and online monitoring of the reac... Higher-order modes of the neutron diffusion/transport equation can be used to study the temporal behavior of nuclear reactors and can be applied in modal analysis, transient analysis, and online monitoring of the reactor core. Both the deterministic method and the Monte Carlo(MC) method can be used to solve the higher-order modes. However, MC method, compared to the deterministic method, faces challenges in terms of computational efficiency and α mode calculation stability, whereas the deterministic method encounters issues arising from homogenization-related geometric and energy spectra adaptation.Based on the higher-order mode diffusion calculation code HARMONY, we developed a new higher-order mode calculation code, HARMONY2.0, which retains the functionality of computing λ and α higher-order modes from HARMONY1.0, but enhances the ability to treat complex geometries and arbitrary energy spectra using the MC-deterministic hybrid two-step strategy. In HARMONY2.0, the mesh homogenized multigroup constants were obtained using OpenMC in the first step,and higher-order modes were then calculated with the mesh homogenized core diffusion model using the implicitly restarted Arnoldi method(IRAM), which was also adopted in the HARMONY1.0 code. In addition, to improve the calculation efficiency, particularly in large higher-order modes, event-driven parallelization/domain decomposition methods are embedded in the HARMONY2.0 code to accelerate the inner iteration of λ∕α mode using OpenMP. Furthermore, the higher-order modes of complex geometric models, such as Hoogenboom and ATR reactors for λ mode and the MUSE-4 experiment facility for the prompt α mode, were computed using diffusion theory. 展开更多
关键词 Neutron diffusion equation higher-order modes Global homogenization Two-step method DOMAIN
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Investigation of the relationship between nurses’levels of mental health literacy,holistic nursing competencies,and professional selfefficacy
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作者 Kubra Durmus Havva Akpinar 《World Journal of Psychiatry》 2025年第4期251-260,共10页
BACKGROUND Given their responsibility for the well-being of individuals,nurses with advanced mental health literacy,along with strong holistic nursing competencies and professional self-efficacy,are better equipped to... BACKGROUND Given their responsibility for the well-being of individuals,nurses with advanced mental health literacy,along with strong holistic nursing competencies and professional self-efficacy,are better equipped to assess both the mental and physical health of their patients,leading to the provision of holistic nursing care.AIM To investigate the relationship between nurses’mental health literacy levels and their holistic nursing competencies,as well as their nursing professional selfefficacy.METHODS This study is cross-sectional,correlational research.The study sample consisted of a total of 261 volunteer nurses working in a training and research hospital and a state hospital between March 11,2024 and April 8,2024.Data were collected face to face with the“Descriptive Data Form”,“Mental Health Literacy Scale(MHLS)”,“Holistic Nursing Competence Scale(HNCS)”,and the“Nursing Profession Self-Efficacy Scale(NPSES)”.RESULTS The mean scale scores for the nurses were as follows:MHLS:95.88±11.67;HNCS:179.46±33.82;NPSES:64.79±11.24.A low-level positive correlation was found between the total scores of the MHLS,HNCS,and NPSES,and a moderate-level positive correlation was observed between the total scores of the HNCS and NPSES.These correlations were statistically significant(P<0.05).CONCLUSION It is recommended that initiatives be undertaken to enhance the mental health literacy and holistic nursing competencies of nurses and that similar studies be conducted with nurses in different institutions and with a larger number of nurses. 展开更多
关键词 Mental health LITERACY HOLISTIC competENCE Nursing SELF-EFFICACY
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Well-Posedness and Asymptotic Behavior of a Higher-Order Kirchhoff Equation
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作者 ZHANG Liao LI Feng-jie 《Chinese Quarterly Journal of Mathematics》 2025年第4期417-440,共24页
This paper focuses on the investigation of a hyperbolic Kirchhoff equation with nonlinear damping and higher-order dissipation terms.Initially,the existence and uniqueness of local weak solutions are rigorously establ... This paper focuses on the investigation of a hyperbolic Kirchhoff equation with nonlinear damping and higher-order dissipation terms.Initially,the existence and uniqueness of local weak solutions are rigorously established.Next,within the framework of potential well theory,the classification of solution behaviors,including blow-up and global existence,is systematically analyzed according to the relationships among the exponents of nonlinear source terms.Finally,explicit bounds for the blow-up time and decay estimates for global solutions are presented. 展开更多
关键词 higher-order dissipation Kirchhoff equation BLOW-UP Blow-up time Decay estimate
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Riemann-Hilbert approach to the higher-order Kaup-Newell equation on the half line
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作者 Hui Yu Ning Zhang 《Chinese Physics B》 2025年第3期231-243,共13页
The higher-order Kaup-Newell equation is examined by applying the Fokas unified method on the half-line.We demonstrate that the solution can be expressed in relation to the resolution of the Riemann-Hilbert problem.Th... The higher-order Kaup-Newell equation is examined by applying the Fokas unified method on the half-line.We demonstrate that the solution can be expressed in relation to the resolution of the Riemann-Hilbert problem.The jump matrix for this problem is derived from the spectral matrix,which is calculated based on both the initial conditions and the boundary conditions.The jump matrix is explicitly dependent and expressed through the spectral functions,which are derived from the initial and boundary information,respectively.These spectral functions are interdependent and adhere to a so-called global relationship. 展开更多
关键词 higher-order Kaup-Newell equation Fokas unified method Riemann-Hilbert problem
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Exact boundary controllability for the periodic higher-order KdV type equations
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作者 JIN Yanpeng FU Ying 《纯粹数学与应用数学》 2025年第3期413-421,共9页
In this paper,the exact boundary controllability of the higher-order KdVtype equation on torus is studied.That is,given the initial and final states in the appropriate space,by adding the appropriate control function ... In this paper,the exact boundary controllability of the higher-order KdVtype equation on torus is studied.That is,given the initial and final states in the appropriate space,by adding the appropriate control function on the boundary,the solution of the system can transition from the initial state to the specified final value.Firstly,we establish the observability inequality for the higher-order KdV-type equation by Ingham inequality.Then,based on the observability inequality,Hilbert uniqueness method and a integral identity we obtain the exact boundary controllability of the higher-order KdV-type equation. 展开更多
关键词 higher-order KdV equation OBSERVABILITY exact boundary controllability
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Higher-order topology in twisted multilayer systems:A review
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作者 Chunbo Hua Dong-Hui Xu 《Chinese Physics B》 2025年第3期2-10,共9页
In recent years,there has been a surge of interest in higher-order topological phases(HOTPs)across various disciplines within the field of physics.These unique phases are characterized by their ability to harbor topol... In recent years,there has been a surge of interest in higher-order topological phases(HOTPs)across various disciplines within the field of physics.These unique phases are characterized by their ability to harbor topological protected boundary states at lower-dimensional boundaries,a distinguishing feature that sets them apart from conventional topological phases and is attributed to the higher-order bulk-boundary correspondence.Two-dimensional(2D)twisted systems offer an optimal platform for investigating HOTPs,owing to their strong controllability and experimental feasibility.Here,we provide a comprehensive overview of the latest research advancements on HOTPs in 2D twisted multilayer systems.We will mainly review the HOTPs in electronic,magnonic,acoustic,photonic and mechanical twisted systems,and finally provide a perspective of this topic. 展开更多
关键词 higher-order topology twisted multilayer systems van der Waals materials corner states
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Symmetry of traveling wave solutions for a Camassa–Holm type equation with higher-order nonlinearity
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作者 Wenguang Cheng Ji Lin 《Communications in Theoretical Physics》 2025年第7期14-18,共5页
We are concerned with a Camassa-Holm type equation with higher-order nonlinearity including some integrable peakon models such as the Camassa-Holm equation,the Degasperis-Procesi equation,and the Novikov equation.We s... We are concerned with a Camassa-Holm type equation with higher-order nonlinearity including some integrable peakon models such as the Camassa-Holm equation,the Degasperis-Procesi equation,and the Novikov equation.We show that all the horizontal symmetric waves for this equation must be traveling waves.This extends the previous results for the Camassa-Holm and Novikov equations. 展开更多
关键词 Camassa-Holm type equation with higher-order nonlinearity traveling waves weak solutions
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On the Cultivation Path of Core Competencies for College English Talents Under the Background of New Liberal Arts
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作者 XIANYU Jing 《Journalism and Mass Communication》 2025年第2期55-60,共6页
This paper elaborates on the approaches to cultivating core competencies for college English talents under the background of New Liberal Arts,focusing on four key aspects:transmitting of Chinese culture in English to ... This paper elaborates on the approaches to cultivating core competencies for college English talents under the background of New Liberal Arts,focusing on four key aspects:transmitting of Chinese culture in English to cultivate students’cultural confidence in the context of globalization,fostering their interdisciplinary competencies through the crossover of different disciplines and knowledge fusion,utilizing big data and emerging technologies to develop students’language proficiency and autonomous learning abilities,and aligning education with societal needs by integrating theoretical learning with practical teaching,thereby enhancing students’social engagement and problem-solving skills.The study aims to advance the reform of foreign language education in the new era,enhance the competitiveness of future professionals,and guide students toward a sound personal and professional development. 展开更多
关键词 New Liberal Arts core competencies college English cultivation path
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Research and Practice of Higher Vocational English Courses Based on Core Competencies
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作者 Xiaofang Tian 《Journal of Contemporary Educational Research》 2025年第6期50-57,共8页
This study investigates and explores the teaching of higher vocational English courses for non-English majors from the perspective of core competencies.First,it outlines the current research status of core competencie... This study investigates and explores the teaching of higher vocational English courses for non-English majors from the perspective of core competencies.First,it outlines the current research status of core competencies and analyzes the national-level requirements for English core competencies.Subsequently,based on professional training objectives and curriculum standards,a questionnaire on the core competencies of English courses has been designed to understand students’perceptions and experiences regarding the development of their competencies in areas such as workplace communication,cross-cultural exchange,language thinking enhancement,and autonomous learning improvement.The survey results showed that the majority of students had a positive attitude towards the effectiveness of English courses in cultivating the aforementioned core competencies.However,some students also suggest improvements,such as increasing practical opportunities and strengthening cultural exchange.Based on this,the study further explores how to integrate the cultivation of core competencies into classroom teaching,including the use of a combination of formative and summative assessments,the design of teaching content and activities related to the workplace and cross-cultural communication,and the guidance of students to actively explore and apply their knowledge,thereby enhancing their English language application abilities.This study has certain reference value for the optimization of the higher vocational English curriculum system and the reform of teaching methods. 展开更多
关键词 Core competencies Vocational English courses Research and practice
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Intrinsic higher-order topological states in two-dimensional honeycomb quantum spin Hall insulators
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作者 Sibin Lü Jun Hu 《Chinese Physics B》 2025年第11期499-504,共6页
The exploration of topological phases remains a cutting-edge research frontier,driven by their promising potential for next-generation electronic and quantum technologies.In this work,we employ first-principles calcul... The exploration of topological phases remains a cutting-edge research frontier,driven by their promising potential for next-generation electronic and quantum technologies.In this work,we employ first-principles calculations and tightbinding modeling to systematically investigate the topological properties of freestanding two-dimensional(2D)honeycomb Bi,HgTe,and Al_(2)O_(3)(0001)-supported HgTe.Remarkably,all three systems exhibit coexistence of intrinsic first-and higher-order topological insulator states,induced by spin-orbit coupling(SOC).These states manifest as topologically protected gapless edge states in one-dimensional(1D)nanoribbons and symmetry-related corner states in zero-dimensional(0D)nanoflakes.Furthermore,fractional electron charges may accumulate at the corners of armchair-edged nanoflakes.Among these materials,HgTe/Al_(2)O_(3)(0001)is particularly promising due to its experimentally feasible atomic configuration and low-energy corner states.Our findings highlight the importance of exploring higher-order topological phases in quantum spin Hall insulators and pave the way for new possibilities in device applications. 展开更多
关键词 higher-order topological insulators two-dimensional honeycomb lattice quantum spin Hall insulators
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Research on Evaluation Scheme for Quantitative Sense from the Perspective of Core Competencies:Taking the Measurement Unit of the Sixth Unit in the First Volume of the Second Grade of the Beijing Normal University Edition as an Example
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作者 Jia Gu Yunxia He 《Journal of Contemporary Educational Research》 2025年第7期169-175,共7页
The implementation of core competencies clarifies social talent needs and guides math classroom evaluation.Lower-grade primary students,highly malleable,need targeted teacher guidance.Teaching evaluation should meet t... The implementation of core competencies clarifies social talent needs and guides math classroom evaluation.Lower-grade primary students,highly malleable,need targeted teacher guidance.Teaching evaluation should meet the talent demands of the times,focusing on core literacy and essential character development.From this perspective,primary math teachers should optimize evaluation,build a diversified system,help students grow in math,find their learning position,and advance confidently. 展开更多
关键词 Core competencies Lower primary school Quantitative sense Evaluation scheme
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Magneto-Electro-Elastic Analysis of Doubly-Curved Shells: Higher-Order Equivalent Layer-Wise Formulation
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作者 Francesco Tornabene Matteo Viscoti Rossana Dimitri 《Computer Modeling in Engineering & Sciences》 2025年第2期1767-1838,共72页
Recent engineering applications increasingly adopt smart materials,whose mechanical responses are sensitive to magnetic and electric fields.In this context,new and computationally efficient modeling strategies are ess... Recent engineering applications increasingly adopt smart materials,whose mechanical responses are sensitive to magnetic and electric fields.In this context,new and computationally efficient modeling strategies are essential to predict the multiphysic behavior of advanced structures accurately.Therefore,the manuscript presents a higher-order formulation for the static analysis of laminated anisotropic magneto-electro-elastic doubly-curved shell structures.The fundamental relations account for the full coupling between the electric field,magnetic field,and mechanical elasticity.The configuration variables are expanded along the thickness direction using a generalized formulation based on the Equivalent Layer-Wise approach.Higher-order polynomials are selected,allowing for the assessment of prescribed values of the configuration variables at the top and bottom sides of solids.In addition,an effective strategy is provided for modeling general surface distributions of mechanical pressures and electromagnetic external fluxes.The model is based on a continuum-based formulation which employs an analytical homogenization of the multifield material properties,based on Mori&Tanaka approach,of a magneto-electro-elastic composite material obtained from a piezoelectric and a piezomagnetic phase,with coupled magneto-electro-elastic effects.A semi-analytical Navier solution is applied to the fundamental equations,and an efficient post-processing equilibrium-based procedure is here used,based on the numerical assessment with the Generalized Differential Quadrature(GDQ)method,to recover the response of three-dimensional shells.The formulation is validated through various examples,investigating the multifield response of panels of different curvatures and lamination schemes.An efficient homogenization procedure,based on the Mori&Tanaka approach,is employed to obtain the three-dimensional constitutive relation of magneto-electro-elastic materials.Each model is validated against three-dimensional finite-element simulations,as developed in commercial codes.Furthermore,the full coupling effect between the electric and magnetic response is evaluated via a parametric investigation,with useful insights for design purposes of many engineering applications.The paper,thus,provides a formulation for the magneto-electro-elastic analysis of laminated structures,with a high computational efficiency,since it provides results with three-dimensional capabilities with a two-dimensional formulation.The adoption of higher-order theories,indeed,allows us to efficiently predict not only the mechanical response of the structure as happens in existing literature,but also the through-the-thickness distribution of electric and magnetic variables.A novel higher-order theory has been proposed in this work for the magneto-electro-elastic analysis of laminated shell structures with varying curvatures.This theory employs a generalized method to model the distribution of the displacement field components,electrostatic,and magneto-static potential,accounting for higher-order polynomials.The thickness functions have been defined to prescribe the arbitrary values of configuration variables at the top and bottom surfaces,even though the model is ESL-based.The fundamental governing equations have been derived in curvilinear principal coordinates,considering all coupling effects among different physical phenomena,including piezoelectric,piezomagnetic,and magneto-electric effects.A homogenization algorithm based on a Mori&Tanaka approach has been adopted to obtain the equivalent magneto-electro-mechanical properties of a two-phase transversely isotropic composite.In addition,an effective method has been adopted involving the external loads in terms of surface tractions,as well as the electric and magnetic fluxes.In the post-processing stage,a GDQ-based procedure provides the actual 3D response of a doubly-curved solid.The model has been validated through significant numerical examples,showing that the results of this semi-analytical theory align well with those obtained from 3D numerical models from commercial codes.In particular,the accuracy of the model has been verified for lamination schemes with soft layers and various curvatures under different loading conditions.Moreover,this formulation has been used to predict the effect of combined electric and magnetic loads on the mechanical response of panels with different curvatures and lamination schemes.As a consequence,this theory can be applied in engineering applications where the combined effect of electric and magnetic loads is crucial,thus facilitating their study and design.An existing limitation of this study is that the solution is that it is derived only for structures with uniform curvature,cross-ply lamination scheme,and simply supported boundary conditions.Furthermore,it requires that each lamina within the stacking sequence exhibits magneto-electro-elastic behavior.Therefore,at the present stage,it cannot be used for multifield analysis of classical composite structures with magneto-electric patches.A further enhancement of the research work could be the derivation of a solution employing a numerical technique,to overcome the limitations of the Navier method.In this way,the same theory may be adopted to predict the multifield response of structures with variable curvatures and thickness,as well as anisotropic materials and more complicated boundary conditions.Acknowledgement:The authors are grateful to the Department of Innovation Engineering of Univer-sity of Salento for the support. 展开更多
关键词 Magneto-electro-elastic materials equivalent layer-wise generalized differential quadrature higher-order theories navier solution recovery procedure smart structures
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An Action Research on Achieving English Core Competencies through Whole Book Reading
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作者 HE Ai-jing ZHENG Yu-ling HU Yi-xian 《Journal of Literature and Art Studies》 2025年第7期566-572,共7页
This research explores whether whole book reading can realize the educational value of English through two rounds of action research.It was found that English core competencies can be achieved through careful selectio... This research explores whether whole book reading can realize the educational value of English through two rounds of action research.It was found that English core competencies can be achieved through careful selection of books,elaborately designed learner-centered reading tasks and teaching activities. 展开更多
关键词 whole book reading English core competencies
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