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Optimal Synchronization of Higher-Order Dynamical Networks 被引量:1
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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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Examining Resource Dependency and Socioeconomic Disparities:A Case Study of Sustaining Rural Livelihoods in India
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作者 Preeti Jakhwal Himanshu Sahu +6 位作者 Aman Srivastava Arun Pratap Mishra AmitKumar Kiran Rawat Mriganka Shekhar Sarkar Sachin Sharma Upaka Rathnayake 《Journal of Environmental & Earth Sciences》 2025年第10期23-45,共23页
Rural communities in developing countries often struggle with resource dependency,economic challenges,and poor infrastructure,and villages in Uttarakhand,India,are no exception.This study aims to examine the socioecon... Rural communities in developing countries often struggle with resource dependency,economic challenges,and poor infrastructure,and villages in Uttarakhand,India,are no exception.This study aims to examine the socioeconomic factors influencing forest conservation,assess livelihood dependency on forest resources,and evaluate how socioeconomic status shapes sustainable forest management in Shishambara and Buddhi villages in Dehradun.The study employed purposive and random sampling covering 10%of households,using structured surveys,interviews,field observations,market surveys,and focus group discussions.The survey reveals an agriculture-dominated livelihood,engaging 60%in Buddhi and 65%in Shishambara,alongside private-sector jobs and daily wage labour.Literacy rates differ significantly,with Buddhi at 72%and Shishambara at 58%.Despite accessibility to LPG connections,traditional cooking fuels like fuelwood and cow dung remain predominant,utilized by 70%of households in Buddhi and 75%in Shishambara.Most homes are Pakka,yet only 18.8%in Buddhi and 22%in Shishambara have toilets.Public transport is scarce,leaving villagers reliant on private vehicles.These findings underscore the need for policies that address resource management,improve basic services,and support sustainable development,offering a road map for uplifting rural livelihoods and bridging infrastructure gaps. 展开更多
关键词 Agricultural dependency Forest dependency Health and Hygiene Rural Livelihoods Sustainable Development Socioeconomic Status
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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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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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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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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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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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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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The Relationship between Mobile Phone Dependency and Academic Burnout in Middle and High School Students
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作者 Miao Wang Meng lin Zhao +3 位作者 Dangyang Ma Xinyu Ji Donghe Li Zhansheng Xu 《International Journal of Mental Health Promotion》 2025年第8期1165-1180,共16页
Background:With the proliferation of smartphones,adolescent mobile phone dependency has intensified,potentially precipitating academic burnout and other adverse outcomes among students.Contemporary study mostly examin... Background:With the proliferation of smartphones,adolescent mobile phone dependency has intensified,potentially precipitating academic burnout and other adverse outcomes among students.Contemporary study mostly examines college populations,resulting in a lack of exploration on the internal mechanisms connecting mobile phone dependency to academic burnout.In addition to analysing the chain-mediated effects of sleep quality and cognitive flexibility,this study sought to provide theoretical insights for prevention by applying the Conservation of Resources theory to examine the relationship between academic burnout and mobile phone dependency among middle and high school students.Methods:A cluster convenience sampling approach was adopted.Data were collected from 811 middle and high school students in Tianjin,China,using a paper-based questionnaire battery comprising the Mobile Phone Addiction Index,the Pittsburgh Sleep Quality Index,the Cognitive Flexibility Scale,and the Adolescent Academic Burnout Scale.Descriptive statistics and correlation analyses were conducted using SPSS 25.0.Chain mediation effects were examined via the PROCESS macro,with significance assessed using bias-corrected bootstrap 95%confidence intervals.Results:A statistically significant positive link exists between mobile phone dependency and academic burnout among middle and high school students(r=0.575,p<0.001).Dependence on mobile phones had a substantial direct impact on academic burnout(β=0.303,p<0.001).Chain mediation analysis revealed that mobile phone dependency had a substantial direct impact on academic burnout(β=0.303,p<0.001).Sleep quality and cognitive flexibility mediated the link between mobile phone dependency and academic burnout.These indirect pathways represent 44.18%of the total effect.Conclusions:Mobile phone dependency contributes to academic burnout amongmiddle and high school students,mediated sequentially by sleep quality and cognitive flexibility.These findings suggest a potential intervention strategy to mitigate academic burnout by targeting excessive mobile phone use,enhancing sleep hygiene,and implementing cognitive flexibility training. 展开更多
关键词 Academic burnout cognitive flexibility mobile phone dependency student development sleep quality
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STDNet:Improved lip reading via short-term temporal dependency modeling
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作者 Xiaoer WU Zhenhua TAN +1 位作者 Ziwei CHENG Yuran RU 《虚拟现实与智能硬件(中英文)》 2025年第2期173-187,共15页
Background Lip reading uses lip images for visual speech recognition.Deep-learning-based lip reading has greatly improved performance in current datasets;however,most existing research ignores the significance of shor... Background Lip reading uses lip images for visual speech recognition.Deep-learning-based lip reading has greatly improved performance in current datasets;however,most existing research ignores the significance of short-term temporal dependencies of lip-shape variations between adjacent frames,which leaves space for further improvement in feature extraction.Methods This article presents a spatiotemporal feature fusion network(STDNet)that compensates for the deficiencies of current lip-reading approaches in short-term temporal dependency modeling.Specifically,to distinguish more similar and intricate content,STDNet adds a temporal feature extraction branch based on a 3D-CNN,which enhances the learning of dynamic lip movements in adjacent frames while not affecting spatial feature extraction.In particular,we designed a local–temporal block,which aggregates interframe differences,strengthening the relationship between various local lip regions through multiscale convolution.We incorporated the squeeze-and-excitation mechanism into the Global-Temporal Block,which processes a single frame as an independent unitto learn temporal variations across the entire lip region more effectively.Furthermore,attention pooling was introduced to highlight meaningful frames containing key semantic information for the target word.Results Experimental results demonstrated STDNet's superior performance on the LRW and LRW-1000,achieving word-level recognition accuracies of 90.2% and 53.56%,respectively.Extensive ablation experiments verified the rationality and effectiveness of its modules.Conclusions The proposed model effectively addresses short-term temporal dependency limitations in lip reading,and improves the temporal robustness of the model against variable-length sequences.These advancements validate the importance of explicit short-term dynamics modeling for practical lip-reading systems. 展开更多
关键词 Lip reading Spatio-temporal feature fusion Short-term temporal dependency modeling
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Dynamical analysis and localized waves of the n-component nonlinear Schrödinger equation with higher-order effects
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作者 Yu Lou Guoan Xu 《Chinese Physics B》 2025年第3期204-213,共10页
Under investigation is the n-component nonlinear Schrödinger equation with higher-order effects,which describes the ultrashort pulses in the birefringent fiber.Based on the Lax pair,the eigenfunction and generali... Under investigation is the n-component nonlinear Schrödinger equation with higher-order effects,which describes the ultrashort pulses in the birefringent fiber.Based on the Lax pair,the eigenfunction and generalized Darboux transformation are derived.Next,we construct several novel higher-order localized waves and classified them into three categories:(i)higher-order rogue waves interacting with bright/antidark breathers,(ii)higher-order breather fission/fusion,(iii)higherorder breather interacting with soliton.Moreover,we explore the effects of parameters on the structure,collision process and energy distribution of localized waves and these characteristics are significantly different from previous ones.Finally,the dynamical properties of these solutions are discussed in detail. 展开更多
关键词 n-component nonlinear Schrödinger equation with higher-order effects generalized Darboux transformation localized waves soliton BREATHER rogue wave
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New insights into the creep degradation mechanisms in thermal barrier coating/single-crystal superalloy system with temperature and stress dependency
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作者 Hao Su Luqing Cui +7 位作者 Zhenyang Cao Xiaofeng Dang Liyin Zhang Jinguo Li Sihai Luo Qihu Wang Weifeng He Xiaoqing Liang 《Journal of Materials Science & Technology》 2025年第25期75-91,共17页
Thermal barrier coating(TBC)is crucial for the performance of turbine blades at high temperatures;however,it degrades the microstructure of single-crystal superalloy(SX),thereby reducing creep life.Despite this,the de... Thermal barrier coating(TBC)is crucial for the performance of turbine blades at high temperatures;however,it degrades the microstructure of single-crystal superalloy(SX),thereby reducing creep life.Despite this,the degradation mechanisms associated with the complex multi-layer damage and inter-layer diffusion behavior for TBC/SX systems have not yet been fully elucidated.In this study,using integrated experimental efforts and multiscale characterization techniques,the creep degradation mechanisms of TBC/SX systems at 900℃/500 MPa,980℃/300 MPa,and 1050℃/160 MPa are systematically investigated.Results demonstrate that the creep degradation from TBC intensifies with increasing temperature(T)and stress(σ)ratio(T/σ),exhibiting significant dependency on these two factors,and primarily reduces lifespan of the steady-state stage,with minimal effects on the accelerating stage.During creep deformation,the cracking behavior caused by thermally grown oxide(TGO)beneath the top coat(TC)layer,voids resulting from internal oxidation and interdiffusion in the bond coat(BC)layer,and the recrystallization growth driven by the sandblasting process in the secondary reaction zone(SRZ)are temperature-sensitive damages.In contrast,the initiation and propagation of cracks associated with the topologically close-packed(TCP)phases in the SRZ exhibit pronounced stress sensitivity.Furthermore,the formation of the substrate diffusion zone(SDZ)and the decomposition ofγ/γ′interfacial dislocation networks driven by the Cr-Ru diffusion,as well as the increased stacking fault energy in theγ′phase due to Co loss,are responsible for the acceleration of steady-state creep rate at 1050℃/160 MPa.This work provides a comprehensive and in-depth understanding of the degradation mechanisms under thermal-mechanical coupling in TBC/SX systems,offering new insights into targeted design optimization for multilayered coatings. 展开更多
关键词 Nickel-based single-crystal superalloy Thermal barrier coating(TBC) Creep degeneration mechanisms Temperature and stress dependence
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APPLICATIONS OF HIGHER-ORDER UPWIND SCHEME FOR PROJECTILES IN TRANSONIC FLOW
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作者 鞠玉涛 郑亚 武晓松 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
针对弹丸跨音速粘性绕流流场进行了数值仿真研究,并与实验进行了对比。数值仿真的控制方程为雷诺平均的Navier-Stokes方程,湍流模型采用Baldwin-Lomax模型,应用了四阶的MUSCL TVD格式。结果表明,该方法可以取得高清晰度的流场结构。
关键词 TVD格式 NAVIER-STOKES方程 弹丸流动 APPLICATIONS OF higher-order UPWIND SCHEME FOR
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WPF精粹(三)——Dependency Property
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作者 蔡学镛 《程序员》 2007年第5期98-100,共3页
WPF能够让XAML描述出来的GUI轻易地使用animation、data binding、trigger、template、style等特色,为了要采用一致的行为来处理这全部的特色,有了全新的事件模型和全新的property——dependenct property。
关键词 dependency dependency TEMPLATE TRIGGER 事件模型 GUI
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