Due to the inability of manufacturing a single monolithic mirror at the 10-meter scales,segmented mirrors have become indispensable tools in modern astronomical research.However,to match the imaging performance of the...Due to the inability of manufacturing a single monolithic mirror at the 10-meter scales,segmented mirrors have become indispensable tools in modern astronomical research.However,to match the imaging performance of the monolithic counterpart,the sub-mirrors must maintain precise co-phasing.Piston error critically degrades segmented mirror imaging quality,necessitating efficient and precise detection.To ad-dress the limitations that the conventional circular-aperture diffraction with two-wavelength algorithm is sus-ceptible to decentration errors,and the traditional convolutional neural networks(CNNs)struggle to capture global features under large-range piston errors due to their restricted local receptive fields,this paper pro-poses a method that integrates extended Young’s interference principles with a Vision Transformer(ViT)to detect piston error.By suppressing decentration error interference through two symmetrically arranged aper-tures and extending the measurement range to±7.95μm via a two-wavelength(589 nm/600 nm)algorithm.This approach exploits ViT’s self-attention mechanism to model global characteristics of interference fringes.Unlike CNNs constrained by local convolutional kernels,the ViT significantly improves sensitivity to inter-ferogram periodicity.The simulation results demonstrate that the proposed method achieves a measurement accuracy of 5 nm(0.0083λ0)across the range of±7.95μm,while maintaining an accuracy exceeding 95%in the presence of Gaussian noise(SNR≥15 dB),Poisson noise(λ≥9 photons/pixel),and sub-mirror gap er-ror(Egap≤0.2)interference.Moreover,the detection speed shows significant improvement compared to the cross-correlation algorithm.This study establishes an accurate,robust framework for segmented mirror error detection,advancing high-precision astronomical observation.展开更多
This article investigates the robust current tracking control problem of three-phase grid-connected inverters with LCL filter under external disturbance by a dynamic state feedback control method.First,this paper cons...This article investigates the robust current tracking control problem of three-phase grid-connected inverters with LCL filter under external disturbance by a dynamic state feedback control method.First,this paper constructs an internal model to learn the information of the states and input of the grid-connected inverter under steady state.Second,by utilizing the internal model principle,the paper turns the tracking control problem into the robust stabilization control problem based on some appropriate coordinate transformations.Then,The paper designs a dynamics state feedback control law to deal with this robust stabilization problem,and thus the solution of the robust current tracking control problem of three-phase grid-connected inverters can be obtained.This control method can ensure the asymptotic stability of the closedloop system.Finally,the paper illustrates the effectiveness of the proposed control approach through several groups of simulations,and compares it with the feedforward control method to verify the robustness of the proposed control method to uncertain parameters.展开更多
In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocal...In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocally diffusive species and degenerately diffusive species.We prove that the traveling wavefronts are exponentially stable,when the initial perturbation around the traveling waves decays exponentially as x→-∞,but in other locations,the initial data can be arbitrarily large.The adopted methods are the weighted energy with the comparison principle and squeezing technique.展开更多
On the threshold of 55 years of diplomatic relations,Cyprus and China stand to gain significantly by deepening their cooperation in trade,tourism,and green technology,guided by mutual respect and shared principles.WIT...On the threshold of 55 years of diplomatic relations,Cyprus and China stand to gain significantly by deepening their cooperation in trade,tourism,and green technology,guided by mutual respect and shared principles.WITH a population of approximately one million,Cyprus is a small country compared to China,which is home to more than 1.4 billion people.展开更多
Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexib...Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexible fiber sensors.Through the preform-tofiber manufacturing technique,a variety of fiber sensors with complex functionalities spanning from the nanoscale to kilometer scale can be automated in a short time.Examples include temperature,acoustic,mechanical,chemical,biological,optoelectronic,and multifunctional sensors,which operate on diverse sensing principles such as resistance,capacitance,piezoelectricity,triboelectricity,photoelectricity,and thermoelectricity.This review outlines the principles of the thermal drawing process and provides a detailed overview of the latest advancements in various thermally drawn fiber sensors.Finally,the future developments of thermally drawn fiber sensors are discussed.展开更多
This paper investigates the following mixed local and nonlocal elliptic problem fea-turing concave-convex nonlinearities and a discontinuous right-hand side:{L(u)=H(u−μ)|u|^(p−2)u+λ|u|^(q−2)u,x∈Ω,u≥0,x∈Ω,u=0,x...This paper investigates the following mixed local and nonlocal elliptic problem fea-turing concave-convex nonlinearities and a discontinuous right-hand side:{L(u)=H(u−μ)|u|^(p−2)u+λ|u|^(q−2)u,x∈Ω,u≥0,x∈Ω,u=0,x∈R^(N)\Ω,where Ω ⊂R^(N)(N>2)is a bounded domain,μ≥0 and λ>0 are real parameters,H denotes the Heaviside function(H(t)=0 for t<0,H(t)=1 for t>0),and the mixed local and nolocal operator is defined as L(u)=−Δu+(−Δ)^(s)u with(−Δ)^(s) being the restricted fractional Laplace(0<s<1).The exponents satisfy 1<q<2<p.By employing a novel non-smooth variational principle,we establish the existence of an M-solution for this problem and identify a range for the exponent p.展开更多
Due to the digital transformation tendency among cultural institutions and the substantial influence of the social media platform,the demands of visual communication keep increasing for promoting traditional cultural ...Due to the digital transformation tendency among cultural institutions and the substantial influence of the social media platform,the demands of visual communication keep increasing for promoting traditional cultural artifacts online.As an effective medium,posters serve to attract public attention and facilitate broader engagement with cultural artifacts.However,existing poster generation methods mainly rely on fixed templates and manual design,which limits their scalability and adaptability to the diverse visual and semantic features of the artifacts.Therefore,we propose CAPGen,an automated aesthetic Cultural Artifacts Poster Generation framework built on a Multimodal Large Language Model(MLLM)with integrated iterative optimization.During our research,we collaborated with designers to define principles of graphic design for cultural artifact posters,to guide the MLLM in generating layout parameters.Later,we generated these parameters into posters.Finally,we refined the posters using an MLLM integrated with a multi-round iterative optimization mechanism.Qualitative results show that CAPGen consistently outperforms baseline methods in both visual quality and aesthetic performance.Furthermore,ablation studies indicate that the prompt,iterative optimization mechanism,and design principles significantly enhance the effectiveness of poster generation.展开更多
Graph neural networks(GNN)have shown strong performance in node classification tasks,yet most existing models rely on uniform or shared weight aggregation,lacking flexibility in modeling the varying strength of relati...Graph neural networks(GNN)have shown strong performance in node classification tasks,yet most existing models rely on uniform or shared weight aggregation,lacking flexibility in modeling the varying strength of relationships among nodes.This paper proposes a novel graph coupling convolutional model that introduces an adaptive weighting mechanism to assign distinct importance to neighboring nodes based on their similarity to the central node.Unlike traditional methods,the proposed coupling strategy enhances the interpretability of node interactions while maintaining competitive classification performance.The model operates in the spatial domain,utilizing adjacency list structures for efficient convolution and addressing the limitations of weight sharing through a coupling-based similarity computation.Extensive experiments are conducted on five graph-structured datasets,including Cora,Citeseer,PubMed,Reddit,and BlogCatalog,as well as a custom topology dataset constructed from the Open University Learning Analytics Dataset(OULAD)educational platform.Results demonstrate that the proposed model achieves good classification accuracy,while significantly reducing training time through direct second-order neighbor fusion and data preprocessing.Moreover,analysis of neighborhood order reveals that considering third-order neighbors offers limited accuracy gains but introduces considerable computational overhead,confirming the efficiency of first-and second-order convolution in practical applications.Overall,the proposed graph coupling model offers a lightweight,interpretable,and effective framework for multi-label node classification in complex networks.展开更多
In this manuscript,we consider a non-autonomous dynamical system.Using the Carathéodory structure,we define a BS dimension on an arbitrary subset and obtain a Bowen’s equation that illustrates the relation of th...In this manuscript,we consider a non-autonomous dynamical system.Using the Carathéodory structure,we define a BS dimension on an arbitrary subset and obtain a Bowen’s equation that illustrates the relation of the BS dimension to the Pesin-Pitskel topological pressure given by Nazarian[24].Moreover,we establish a variational principle and an inverse variational principle for the BS dimension of non-autonomous dynamical systems.Finally,we also get an analogue of Billingsley’s theorem for the BS dimension of non-autonomous dynamical systems.展开更多
Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems cons...Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems consisting of two insulators.Here,motivated by the emergence of an insulator-metal transition in type-Ⅲ heterostructures and the superconductivity in some“special”two-dimensional(2D)semiconductors via electron doping,we predict that the 2D heterostructure SnSe_(2)/PtTe_(2) is a model system for realizing IS by using firstprinciples calculations.Our results show that due to slight but crucial interlayer charge transfer,SnSe_(2)/PtTe_(2) turns to be a type-Ⅲ heterostructure with metallic properties and shows a superconducting transition with the critical temperature(T_(c))of 3.73 K.Similar to the enhanced electron–phonon coupling(EPC)in the electrondoped SnSe_(2) monolayer,the IS in the SnSe_(2)/PtTe_(2) heterostructure mainly originates from the metallized SnSe_(2) layer.Furthermore,we find that its superconductivity is sensitive to tensile lattice strain,forming a domeshaped superconducting phase diagram.Remarkably,at 7%biaxial tensile strain,the superconducting T_(c) can increase more than twofold(8.80 K),resulting from softened acoustic phonons at the𝑀point and enhanced EPC strength.Our study provides a concrete example for realizing IS in type-Ⅲ heterostructures,which waits for future experimental verification.展开更多
Feature selection serves as a critical preprocessing step inmachine learning,focusing on identifying and preserving the most relevant features to improve the efficiency and performance of classification algorithms.Par...Feature selection serves as a critical preprocessing step inmachine learning,focusing on identifying and preserving the most relevant features to improve the efficiency and performance of classification algorithms.Particle Swarm Optimization has demonstrated significant potential in addressing feature selection challenges.However,there are inherent limitations in Particle Swarm Optimization,such as the delicate balance between exploration and exploitation,susceptibility to local optima,and suboptimal convergence rates,hinder its performance.To tackle these issues,this study introduces a novel Leveraged Opposition-Based Learning method within Fitness Landscape Particle Swarm Optimization,tailored for wrapper-based feature selection.The proposed approach integrates:(1)a fitness-landscape adaptive strategy to dynamically balance exploration and exploitation,(2)the lever principle within Opposition-Based Learning to improve search efficiency,and(3)a Local Selection and Re-optimization mechanism combined with random perturbation to expedite convergence and enhance the quality of the optimal feature subset.The effectiveness of is rigorously evaluated on 24 benchmark datasets and compared against 13 advancedmetaheuristic algorithms.Experimental results demonstrate that the proposed method outperforms the compared algorithms in classification accuracy on over half of the datasets,whilst also significantly reducing the number of selected features.These findings demonstrate its effectiveness and robustness in feature selection tasks.展开更多
We report first-principles predictions of a cage-like polymeric nitrogen phase(cage-N)composed of interlocked N10 clusters stabilized by mixed sp^(2)/sp^(3) hybridization.Under high pressure,cage-N exhibits exceptiona...We report first-principles predictions of a cage-like polymeric nitrogen phase(cage-N)composed of interlocked N10 clusters stabilized by mixed sp^(2)/sp^(3) hybridization.Under high pressure,cage-N exhibits exceptional mechanical performance,including an ideal compressive strength of 343 GPa at a pressure of 300 GPa,~33% higher than that of diamond.This ultrahigh strength arises from the synergistic interplay between its three-dimensional covalent framework and hybridized bonding topology,which enables isotropic stress accommodation and dynamic electronic rearrangement.These results establish cage-N as a promising non-carbon ultrahard material and provide a bonding-driven route toward designing superhard frameworks under extreme conditions.展开更多
We report a theoretical investigation into superconductivity within the MAXH_(6) quaternary hydride system using first-principles calculations,where M and A denote alkali and alkaline earth elements,respectively,and X...We report a theoretical investigation into superconductivity within the MAXH_(6) quaternary hydride system using first-principles calculations,where M and A denote alkali and alkaline earth elements,respectively,and X represents transition metal elements.Systematic analysis of electronic band structures,phonon dispersions,and electron-phonon coupling reveals that substitution of MA binary metal combinations and X metal atoms can create favorable conditions for superconductivity.Mapping of superconducting critical temperatures,combined with dynamical stability analysis through phonon calculations,identifies ten superconducting candidates at ambient pressure.Among these,LiNaAgH_(6) exhibits nearly-free-electron behavior reminiscent of monovalent electron superconductors.It demonstrates exceptional superconducting properties with electron–phonon coupling λ=2.707,which yields a superconducting transition temperature T_(c) of 206.4 K using the Allen–Dynes formula.Its structural analogs MgNaPdH_(6),LiMgPdH_(6),LiMgAgH_(6),LiMgAuH_(6) all exhibit superconducting transition temperatures above 110 K.These findings advance our fundamental understanding of superconductivity in quaternary hydrides and provide guidance for rational design of new high-temperature superconducting materials.展开更多
This essay provides a few critical points of view on Ni Peimin＇s recent English translation of the Analects. It shows that his translations of ren into ＂human-heartedness＂ and of li into ＂ritual propriety＂ may in...This essay provides a few critical points of view on Ni Peimin＇s recent English translation of the Analects. It shows that his translations of ren into ＂human-heartedness＂ and of li into ＂ritual propriety＂ may indicate a willingness to recast these Confucian concepts in the modern ideology of western subjectivism or individualism, whereas Confucianism is not in the direction of such ideologies. Moreover, while Ni seems to offer a ＂no-rule＂ view of Confucian virtue ethics, he cannot deny the existence of moral rules and principles in the Confucian system. It is insufficient for him to emphasize the importance of Confucian ＂instructions＂ or ＂methods＂ as he does without explicating their relations to Confucian rules. Additionally, Ni＇s gongfu Confucianism provides a necessary and healthy step back from the contemporary principlism that has been dominant and popular in contemporary politics, ethics, and applied ethics, but Ni goes too far in denying the importance of the moral rules and principles that are implicit or explicit in the Confucian ritual practices and upheld in Confucius＇s Analects.展开更多
Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-depo...Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-deposited and remelted were developed to refine the microstructure and enhance the oxidation resistance of refractory high entropy alloy using electron beam freeform fabrication(EBF3).Finer and short-range ordering structures were observed in the remelted sample,whereas the Al-deposited sample showcased the formation of silicide and intermetallic phases.High-temperature cyclic and isothermal oxidation tests at 1000℃ were carried out.The total weight gain after 60 h of cyclic oxidation decreased by 17.49%and 30.46%for the remelted and deposited samples,respectively,compared to the as-cast state.Oxidation kinetics reveal an evident lower mass gain and oxidation rate in the treated samples.A multilayer oxide consisting of TiO_(2)+Al_(2)O_(3)+SiO_(2)+AlNbO_(4) was studied for its excellent oxidation resistance.The oxidation behavior of rutile,corundum and other oxides was analyzed using first principles calculations and chemical defect analysis.Overall,this research,which introduces novel treatments,offers promising insights for enhancing the inherent oxidation resistance of refractory high entropy alloys.展开更多
Background Clinical brain-computer interface(BCI)for mental disorders is an emerging interdisciplinary research field,posing new ethical concerns and challenges,yet lacking practical ethical governance guidelines for ...Background Clinical brain-computer interface(BCI)for mental disorders is an emerging interdisciplinary research field,posing new ethical concerns and challenges,yet lacking practical ethical governance guidelines for stakeholders and the entire community.Aims This study aims to establish a multidisciplinary consensus of principles for ethical governance of clinical BCI research for mental disorders and offer practical ethical guidance to stakeholders involved.Methods A systematic literature review,symposium and roundtable discussions,and a pre-Delphi(round 0)survey were conducted to form the questionnaire for the three-round modified Delphi study.Two rounds of surveys,followed by a third round of independent interviews of 25 experts from BCI-related research domains,were involved.We conducted quantitative analysis of responses and agreements among experts to reveal the consensus and differences regarding the ethical governance of mental BCI research from a multidisciplinary perspective.Results The Delphi panel emphasised important concerns of ethical review practices and ethical principles within the BCI context,identified qualified and highly influential institutions and personnel in conducting and advancing clinical BCI research,and recognised prioritised aspects in the risk-benefit evaluation.Experts expressed diverse opinions on specific ethical concerns,including concerns about invasive technology,its impact on humanity and potential social consequences.Agreement was reached that the practices of ethical governance of clinical BCI for mental disorders should focus on patient voluntariness,autonomy,long-term effects and related assessments of BCI interventions,as well as privacy protection,transparent reporting and ensuring that the research is conducted in qualified institutions with strong data security.Conclusions Ethical governance of clinical research on BCI for mental disorders should include interdisciplinary experts to balance various needs and incorporate the expertise of different stakeholders to avoid serious ethical issues.It requires scientifically grounded approaches,continuous monitoring and interdisciplinary collaboration to ensure evidence-based policies,comprehensive risk assessments and transparency,thereby promoting responsible innovations and protecting patient rights and well-being.展开更多
NOx sensors, as a core component of diesel engine exhaust treatment system, play an important role in exhaust emission control, which can accurately and quickly detect the NOx and O2 concentration. It has become a nec...NOx sensors, as a core component of diesel engine exhaust treatment system, play an important role in exhaust emission control, which can accurately and quickly detect the NOx and O2 concentration. It has become a necessary option for the detection of existing exhaust emission standards. At present, there is limited and scattered information on knowledge and test methods of NOx sensors, the research of NOx sensors has become a challenging research topic at home and abroad. Based on these requirements, the article systematically integrates the knowledge of principle and testing methods. First of all, through introducing functional description of NOx sensors and the basic principle of NOx sensors, the relevant scholars can have an overall understanding of the product and master the operation mode of products. Secondly, the current status of performance test bench and methods of NOx sensors were described, which can contribute to having a clear understanding of the development process. After that, a new structure of NOx sensors test bench was purposed, which contains six major units including standard gas source, gas mixing unit, analyzer measurement unit, sensor measurement unit, data processing and display unit, exhaust gas treatment unit. And the test bench was validated. The experimental results show that the test bench has the advantages of high-repeatability, high reliability and low cost. And it can realize automatic detection of multiple target values, which is worthy further promotion. Thereby, the article can contribute to the development of its technology indirectly.展开更多
Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglo...Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglotz type equations for nonholonomic systems are established.Then,the Noether symmetries are studied,and the conserved quantities are obtained.The results are extended to nonholonomic canonical systems,and the Herglotz type canonical equations and the Noether theorems are obtained.Two examples are provided to demonstrate the validity of the methods and results.展开更多
文摘Due to the inability of manufacturing a single monolithic mirror at the 10-meter scales,segmented mirrors have become indispensable tools in modern astronomical research.However,to match the imaging performance of the monolithic counterpart,the sub-mirrors must maintain precise co-phasing.Piston error critically degrades segmented mirror imaging quality,necessitating efficient and precise detection.To ad-dress the limitations that the conventional circular-aperture diffraction with two-wavelength algorithm is sus-ceptible to decentration errors,and the traditional convolutional neural networks(CNNs)struggle to capture global features under large-range piston errors due to their restricted local receptive fields,this paper pro-poses a method that integrates extended Young’s interference principles with a Vision Transformer(ViT)to detect piston error.By suppressing decentration error interference through two symmetrically arranged aper-tures and extending the measurement range to±7.95μm via a two-wavelength(589 nm/600 nm)algorithm.This approach exploits ViT’s self-attention mechanism to model global characteristics of interference fringes.Unlike CNNs constrained by local convolutional kernels,the ViT significantly improves sensitivity to inter-ferogram periodicity.The simulation results demonstrate that the proposed method achieves a measurement accuracy of 5 nm(0.0083λ0)across the range of±7.95μm,while maintaining an accuracy exceeding 95%in the presence of Gaussian noise(SNR≥15 dB),Poisson noise(λ≥9 photons/pixel),and sub-mirror gap er-ror(Egap≤0.2)interference.Moreover,the detection speed shows significant improvement compared to the cross-correlation algorithm.This study establishes an accurate,robust framework for segmented mirror error detection,advancing high-precision astronomical observation.
基金Supported by the Fundamental Research Funds for the Central Universities(2024ZYGXZR047)the National Natural Science Foundation of China(62373156)the Guangdong Basic and Applied Basic Research Foundation(2024A1515011736)。
文摘This article investigates the robust current tracking control problem of three-phase grid-connected inverters with LCL filter under external disturbance by a dynamic state feedback control method.First,this paper constructs an internal model to learn the information of the states and input of the grid-connected inverter under steady state.Second,by utilizing the internal model principle,the paper turns the tracking control problem into the robust stabilization control problem based on some appropriate coordinate transformations.Then,The paper designs a dynamics state feedback control law to deal with this robust stabilization problem,and thus the solution of the robust current tracking control problem of three-phase grid-connected inverters can be obtained.This control method can ensure the asymptotic stability of the closedloop system.Finally,the paper illustrates the effectiveness of the proposed control approach through several groups of simulations,and compares it with the feedforward control method to verify the robustness of the proposed control method to uncertain parameters.
基金Supported by the National Natural Science Foundation of China(Grant No.12261081).
文摘In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocally diffusive species and degenerately diffusive species.We prove that the traveling wavefronts are exponentially stable,when the initial perturbation around the traveling waves decays exponentially as x→-∞,but in other locations,the initial data can be arbitrarily large.The adopted methods are the weighted energy with the comparison principle and squeezing technique.
文摘On the threshold of 55 years of diplomatic relations,Cyprus and China stand to gain significantly by deepening their cooperation in trade,tourism,and green technology,guided by mutual respect and shared principles.WITH a population of approximately one million,Cyprus is a small country compared to China,which is home to more than 1.4 billion people.
基金supported by the National Key Research and Development Program of China(2023YFB3809800)the National Natural Science Foundation of China(52172249,52525601)+2 种基金the Chinese Academy of Sciences Talents Program(E2290701)the Jiangsu Province Talents Program(JSSCRC2023545)the Special Fund Project of Carbon Peaking Carbon Neutrality Science and Technology Innovation of Jiangsu Province(BE2022011).
文摘Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexible fiber sensors.Through the preform-tofiber manufacturing technique,a variety of fiber sensors with complex functionalities spanning from the nanoscale to kilometer scale can be automated in a short time.Examples include temperature,acoustic,mechanical,chemical,biological,optoelectronic,and multifunctional sensors,which operate on diverse sensing principles such as resistance,capacitance,piezoelectricity,triboelectricity,photoelectricity,and thermoelectricity.This review outlines the principles of the thermal drawing process and provides a detailed overview of the latest advancements in various thermally drawn fiber sensors.Finally,the future developments of thermally drawn fiber sensors are discussed.
基金Supported by the National Natural Science Foundation of China(Grant No.12361026)the Discipline Construction Fund Project of Northwest Minzu University.
文摘This paper investigates the following mixed local and nonlocal elliptic problem fea-turing concave-convex nonlinearities and a discontinuous right-hand side:{L(u)=H(u−μ)|u|^(p−2)u+λ|u|^(q−2)u,x∈Ω,u≥0,x∈Ω,u=0,x∈R^(N)\Ω,where Ω ⊂R^(N)(N>2)is a bounded domain,μ≥0 and λ>0 are real parameters,H denotes the Heaviside function(H(t)=0 for t<0,H(t)=1 for t>0),and the mixed local and nolocal operator is defined as L(u)=−Δu+(−Δ)^(s)u with(−Δ)^(s) being the restricted fractional Laplace(0<s<1).The exponents satisfy 1<q<2<p.By employing a novel non-smooth variational principle,we establish the existence of an M-solution for this problem and identify a range for the exponent p.
基金supported by the National Key Research and Development Program of China(2023YFF0906502)the Postgraduate Research and Innovation Project of Hunan Province under Grant(CX20240473).
文摘Due to the digital transformation tendency among cultural institutions and the substantial influence of the social media platform,the demands of visual communication keep increasing for promoting traditional cultural artifacts online.As an effective medium,posters serve to attract public attention and facilitate broader engagement with cultural artifacts.However,existing poster generation methods mainly rely on fixed templates and manual design,which limits their scalability and adaptability to the diverse visual and semantic features of the artifacts.Therefore,we propose CAPGen,an automated aesthetic Cultural Artifacts Poster Generation framework built on a Multimodal Large Language Model(MLLM)with integrated iterative optimization.During our research,we collaborated with designers to define principles of graphic design for cultural artifact posters,to guide the MLLM in generating layout parameters.Later,we generated these parameters into posters.Finally,we refined the posters using an MLLM integrated with a multi-round iterative optimization mechanism.Qualitative results show that CAPGen consistently outperforms baseline methods in both visual quality and aesthetic performance.Furthermore,ablation studies indicate that the prompt,iterative optimization mechanism,and design principles significantly enhance the effectiveness of poster generation.
基金Support by Sichuan Science and Technology Program[2023YFSY0026,2023YFH0004]Guangzhou Huashang University[2024HSZD01,HS2023JYSZH01].
文摘Graph neural networks(GNN)have shown strong performance in node classification tasks,yet most existing models rely on uniform or shared weight aggregation,lacking flexibility in modeling the varying strength of relationships among nodes.This paper proposes a novel graph coupling convolutional model that introduces an adaptive weighting mechanism to assign distinct importance to neighboring nodes based on their similarity to the central node.Unlike traditional methods,the proposed coupling strategy enhances the interpretability of node interactions while maintaining competitive classification performance.The model operates in the spatial domain,utilizing adjacency list structures for efficient convolution and addressing the limitations of weight sharing through a coupling-based similarity computation.Extensive experiments are conducted on five graph-structured datasets,including Cora,Citeseer,PubMed,Reddit,and BlogCatalog,as well as a custom topology dataset constructed from the Open University Learning Analytics Dataset(OULAD)educational platform.Results demonstrate that the proposed model achieves good classification accuracy,while significantly reducing training time through direct second-order neighbor fusion and data preprocessing.Moreover,analysis of neighborhood order reveals that considering third-order neighbors offers limited accuracy gains but introduces considerable computational overhead,confirming the efficiency of first-and second-order convolution in practical applications.Overall,the proposed graph coupling model offers a lightweight,interpretable,and effective framework for multi-label node classification in complex networks.
基金supported by the NSFC(12461012)and the NSF of Chongqing(CSTB2024NSCQ-MSX1246).
文摘In this manuscript,we consider a non-autonomous dynamical system.Using the Carathéodory structure,we define a BS dimension on an arbitrary subset and obtain a Bowen’s equation that illustrates the relation of the BS dimension to the Pesin-Pitskel topological pressure given by Nazarian[24].Moreover,we establish a variational principle and an inverse variational principle for the BS dimension of non-autonomous dynamical systems.Finally,we also get an analogue of Billingsley’s theorem for the BS dimension of non-autonomous dynamical systems.
基金supported by the National Key R&D Program of China (Grant Nos.2022YFA1403103 and 2019YFA0308603)the National Natural Science Foundation of China (Grant No.12304167)the Shandong Provincial Natural Science Foundation of China (Grant No.ZR2023QA020)。
文摘Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems consisting of two insulators.Here,motivated by the emergence of an insulator-metal transition in type-Ⅲ heterostructures and the superconductivity in some“special”two-dimensional(2D)semiconductors via electron doping,we predict that the 2D heterostructure SnSe_(2)/PtTe_(2) is a model system for realizing IS by using firstprinciples calculations.Our results show that due to slight but crucial interlayer charge transfer,SnSe_(2)/PtTe_(2) turns to be a type-Ⅲ heterostructure with metallic properties and shows a superconducting transition with the critical temperature(T_(c))of 3.73 K.Similar to the enhanced electron–phonon coupling(EPC)in the electrondoped SnSe_(2) monolayer,the IS in the SnSe_(2)/PtTe_(2) heterostructure mainly originates from the metallized SnSe_(2) layer.Furthermore,we find that its superconductivity is sensitive to tensile lattice strain,forming a domeshaped superconducting phase diagram.Remarkably,at 7%biaxial tensile strain,the superconducting T_(c) can increase more than twofold(8.80 K),resulting from softened acoustic phonons at the𝑀point and enhanced EPC strength.Our study provides a concrete example for realizing IS in type-Ⅲ heterostructures,which waits for future experimental verification.
基金supported by National Natural Science Foundation of China(62106092)Natural Science Foundation of Fujian Province(2024J01822,2024J01820,2022J01916)Natural Science Foundation of Zhangzhou City(ZZ2024J28).
文摘Feature selection serves as a critical preprocessing step inmachine learning,focusing on identifying and preserving the most relevant features to improve the efficiency and performance of classification algorithms.Particle Swarm Optimization has demonstrated significant potential in addressing feature selection challenges.However,there are inherent limitations in Particle Swarm Optimization,such as the delicate balance between exploration and exploitation,susceptibility to local optima,and suboptimal convergence rates,hinder its performance.To tackle these issues,this study introduces a novel Leveraged Opposition-Based Learning method within Fitness Landscape Particle Swarm Optimization,tailored for wrapper-based feature selection.The proposed approach integrates:(1)a fitness-landscape adaptive strategy to dynamically balance exploration and exploitation,(2)the lever principle within Opposition-Based Learning to improve search efficiency,and(3)a Local Selection and Re-optimization mechanism combined with random perturbation to expedite convergence and enhance the quality of the optimal feature subset.The effectiveness of is rigorously evaluated on 24 benchmark datasets and compared against 13 advancedmetaheuristic algorithms.Experimental results demonstrate that the proposed method outperforms the compared algorithms in classification accuracy on over half of the datasets,whilst also significantly reducing the number of selected features.These findings demonstrate its effectiveness and robustness in feature selection tasks.
基金supported by the Natural Science Foundation of China(Grant Nos.T2325013,52288102,52090024,12034009,12474004,and 12304036)the National Key R&D Program of China Grant No.2023YFA1610000+1 种基金the Fundamental Research Funds for the Central Universitiesthe Program for Jilin University and Sun Yat-sen University.
文摘We report first-principles predictions of a cage-like polymeric nitrogen phase(cage-N)composed of interlocked N10 clusters stabilized by mixed sp^(2)/sp^(3) hybridization.Under high pressure,cage-N exhibits exceptional mechanical performance,including an ideal compressive strength of 343 GPa at a pressure of 300 GPa,~33% higher than that of diamond.This ultrahigh strength arises from the synergistic interplay between its three-dimensional covalent framework and hybridized bonding topology,which enables isotropic stress accommodation and dynamic electronic rearrangement.These results establish cage-N as a promising non-carbon ultrahard material and provide a bonding-driven route toward designing superhard frameworks under extreme conditions.
基金supported by the National Key R&D Program of China (Grant No.2022YFA1403201)the National Natural Science Foundation of China (Grant Nos.12125404,T2495231,123B2049,and 12204138)+9 种基金the Advanced MaterialsNational Science and Technology Major Project (Grant No.2024ZD0607000)the Natural Science Foundation of Jiangsu Province (Grant Nos.BK20233001 and BK20253009)the Jiangsu Funding Program for Excellent Postdoctoral Talent (Grant No.2024ZB002)the China Postdoctoral Science Foundation (Grant No.2025M773331)the Fundamental and Interdisciplinary Disciplines Breakthrough Plan of the Ministry of Education of Chinathe AI&AI for Science program of Nanjing UniversityArtificial Intelligence and Quantum physics (AIQ) program of Nanjing Universitythe Fundamental Research Funds for the Central Universitiesthe Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant Nos.NY224165,NY220038,and NY219087)the Hua Li Talents Program of Nanjing University of Posts and Telecommunications。
文摘We report a theoretical investigation into superconductivity within the MAXH_(6) quaternary hydride system using first-principles calculations,where M and A denote alkali and alkaline earth elements,respectively,and X represents transition metal elements.Systematic analysis of electronic band structures,phonon dispersions,and electron-phonon coupling reveals that substitution of MA binary metal combinations and X metal atoms can create favorable conditions for superconductivity.Mapping of superconducting critical temperatures,combined with dynamical stability analysis through phonon calculations,identifies ten superconducting candidates at ambient pressure.Among these,LiNaAgH_(6) exhibits nearly-free-electron behavior reminiscent of monovalent electron superconductors.It demonstrates exceptional superconducting properties with electron–phonon coupling λ=2.707,which yields a superconducting transition temperature T_(c) of 206.4 K using the Allen–Dynes formula.Its structural analogs MgNaPdH_(6),LiMgPdH_(6),LiMgAgH_(6),LiMgAuH_(6) all exhibit superconducting transition temperatures above 110 K.These findings advance our fundamental understanding of superconductivity in quaternary hydrides and provide guidance for rational design of new high-temperature superconducting materials.
文摘This essay provides a few critical points of view on Ni Peimin＇s recent English translation of the Analects. It shows that his translations of ren into ＂human-heartedness＂ and of li into ＂ritual propriety＂ may indicate a willingness to recast these Confucian concepts in the modern ideology of western subjectivism or individualism, whereas Confucianism is not in the direction of such ideologies. Moreover, while Ni seems to offer a ＂no-rule＂ view of Confucian virtue ethics, he cannot deny the existence of moral rules and principles in the Confucian system. It is insufficient for him to emphasize the importance of Confucian ＂instructions＂ or ＂methods＂ as he does without explicating their relations to Confucian rules. Additionally, Ni＇s gongfu Confucianism provides a necessary and healthy step back from the contemporary principlism that has been dominant and popular in contemporary politics, ethics, and applied ethics, but Ni goes too far in denying the importance of the moral rules and principles that are implicit or explicit in the Confucian ritual practices and upheld in Confucius＇s Analects.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF0609000)National Natural Science Foundation of China(Grant Nos.52171034 and 52101037)Postdoctoral Fellowship Program of CPSFara(No.GZB20230944).
文摘Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-deposited and remelted were developed to refine the microstructure and enhance the oxidation resistance of refractory high entropy alloy using electron beam freeform fabrication(EBF3).Finer and short-range ordering structures were observed in the remelted sample,whereas the Al-deposited sample showcased the formation of silicide and intermetallic phases.High-temperature cyclic and isothermal oxidation tests at 1000℃ were carried out.The total weight gain after 60 h of cyclic oxidation decreased by 17.49%and 30.46%for the remelted and deposited samples,respectively,compared to the as-cast state.Oxidation kinetics reveal an evident lower mass gain and oxidation rate in the treated samples.A multilayer oxide consisting of TiO_(2)+Al_(2)O_(3)+SiO_(2)+AlNbO_(4) was studied for its excellent oxidation resistance.The oxidation behavior of rutile,corundum and other oxides was analyzed using first principles calculations and chemical defect analysis.Overall,this research,which introduces novel treatments,offers promising insights for enhancing the inherent oxidation resistance of refractory high entropy alloys.
基金funded by the Shanghai Philosophy and Social Science Planning Project (2021BZX008)the National Social Science Foundation of China (23BZX110)the National Office for Philosophy and Social Science (20&ZD045).
文摘Background Clinical brain-computer interface(BCI)for mental disorders is an emerging interdisciplinary research field,posing new ethical concerns and challenges,yet lacking practical ethical governance guidelines for stakeholders and the entire community.Aims This study aims to establish a multidisciplinary consensus of principles for ethical governance of clinical BCI research for mental disorders and offer practical ethical guidance to stakeholders involved.Methods A systematic literature review,symposium and roundtable discussions,and a pre-Delphi(round 0)survey were conducted to form the questionnaire for the three-round modified Delphi study.Two rounds of surveys,followed by a third round of independent interviews of 25 experts from BCI-related research domains,were involved.We conducted quantitative analysis of responses and agreements among experts to reveal the consensus and differences regarding the ethical governance of mental BCI research from a multidisciplinary perspective.Results The Delphi panel emphasised important concerns of ethical review practices and ethical principles within the BCI context,identified qualified and highly influential institutions and personnel in conducting and advancing clinical BCI research,and recognised prioritised aspects in the risk-benefit evaluation.Experts expressed diverse opinions on specific ethical concerns,including concerns about invasive technology,its impact on humanity and potential social consequences.Agreement was reached that the practices of ethical governance of clinical BCI for mental disorders should focus on patient voluntariness,autonomy,long-term effects and related assessments of BCI interventions,as well as privacy protection,transparent reporting and ensuring that the research is conducted in qualified institutions with strong data security.Conclusions Ethical governance of clinical research on BCI for mental disorders should include interdisciplinary experts to balance various needs and incorporate the expertise of different stakeholders to avoid serious ethical issues.It requires scientifically grounded approaches,continuous monitoring and interdisciplinary collaboration to ensure evidence-based policies,comprehensive risk assessments and transparency,thereby promoting responsible innovations and protecting patient rights and well-being.
文摘NOx sensors, as a core component of diesel engine exhaust treatment system, play an important role in exhaust emission control, which can accurately and quickly detect the NOx and O2 concentration. It has become a necessary option for the detection of existing exhaust emission standards. At present, there is limited and scattered information on knowledge and test methods of NOx sensors, the research of NOx sensors has become a challenging research topic at home and abroad. Based on these requirements, the article systematically integrates the knowledge of principle and testing methods. First of all, through introducing functional description of NOx sensors and the basic principle of NOx sensors, the relevant scholars can have an overall understanding of the product and master the operation mode of products. Secondly, the current status of performance test bench and methods of NOx sensors were described, which can contribute to having a clear understanding of the development process. After that, a new structure of NOx sensors test bench was purposed, which contains six major units including standard gas source, gas mixing unit, analyzer measurement unit, sensor measurement unit, data processing and display unit, exhaust gas treatment unit. And the test bench was validated. The experimental results show that the test bench has the advantages of high-repeatability, high reliability and low cost. And it can realize automatic detection of multiple target values, which is worthy further promotion. Thereby, the article can contribute to the development of its technology indirectly.
基金supported by the National Natural Science Foundation of China(Grant No.12272248)the Postgraduate Research and Practice Innovation Program of Jiangsu Province of China(Grant No.KYCX23_3296).
文摘Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglotz type equations for nonholonomic systems are established.Then,the Noether symmetries are studied,and the conserved quantities are obtained.The results are extended to nonholonomic canonical systems,and the Herglotz type canonical equations and the Noether theorems are obtained.Two examples are provided to demonstrate the validity of the methods and results.
