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Estimation of peer pressure in dynamic homogeneous social networks
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作者 Jie Liu Pengyi Wang +1 位作者 Jiayang Zhao Yu Dong 《中国科学技术大学学报》 北大核心 2025年第5期36-49,35,I0001,I0002,共17页
Social interaction with peer pressure is widely studied in social network analysis.Game theory can be utilized to model dynamic social interaction,and one class of game network models assumes that people’s decision p... Social interaction with peer pressure is widely studied in social network analysis.Game theory can be utilized to model dynamic social interaction,and one class of game network models assumes that people’s decision payoff functions hinge on individual covariates and the choices of their friends.However,peer pressure would be misidentified and induce a non-negligible bias when incomplete covariates are involved in the game model.For this reason,we develop a generalized constant peer effects model based on homogeneity structure in dynamic social networks.The new model can effectively avoid bias through homogeneity pursuit and can be applied to a wider range of scenarios.To estimate peer pressure in the model,we first present two algorithms based on the initialize expand merge method and the polynomial-time twostage method to estimate homogeneity parameters.Then we apply the nested pseudo-likelihood method and obtain consistent estimators of peer pressure.Simulation evaluations show that our proposed methodology can achieve desirable and effective results in terms of the community misclassification rate and parameter estimation error.We also illustrate the advantages of our model in the empirical analysis when compared with a benchmark model. 展开更多
关键词 dynamic network game theory HOMOGENEITY peer pressure social interaction
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Two-dimensional photothermally induced grating
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作者 Tauqeer Khan Muneeb ur Rahman +3 位作者 Nusrat Riaz Ahsan Bin Asad Muhammad Imtiaz Khan Ziauddin 《Communications in Theoretical Physics》 2025年第6期51-58,共8页
The phenomenon of photothermally induced transparency(PTIT)arises from the nonlinear behavior of an optical cavity,resulting from the heating of mirrors.By introducing a coupling field in the form of a standing wave,P... The phenomenon of photothermally induced transparency(PTIT)arises from the nonlinear behavior of an optical cavity,resulting from the heating of mirrors.By introducing a coupling field in the form of a standing wave,PTIT can be transitioned into photothermally induced grating(PTIG).A two-dimensional(2D)diffraction pattern is achieved through the adjustment of key parameters such as coupling strength and effective detuning.Notably,we observe first,second,and third-order intensity distributions,with the ability to transfer probe energy predominantly to the third order by fine-tuning the coupling strength.The intensity distribution is characterized by(±m,±n),where m,n=1,2,3.This proposed 2D grating system offers a novel platform for manipulating PTIG,presenting unique possibilities for enhanced functionality and control. 展开更多
关键词 GRATING photothermal cavity two dimension
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Homogeneous catalysis and heterogeneous separation:Ionic liquids as recyclable photocatalysts for hydroacylation of olefins
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作者 Hao-Cong Li Ming Zhang +4 位作者 Qiyan Lv Kai Sun Xiao-Lan Chen Lingbo Qu Bing Yu 《Chinese Chemical Letters》 2025年第2期389-393,共5页
The photoinduced ligand-to-metal charge transfer(LMCT)process has been extensively investigated,however,the recovery of photocatalysts has remained a persistent challenge in the field.In light of this issue,a novel ap... The photoinduced ligand-to-metal charge transfer(LMCT)process has been extensively investigated,however,the recovery of photocatalysts has remained a persistent challenge in the field.In light of this issue,a novel approach involving the development of iron-based ionic liquids as photocatalysts has been pursued for the first time,with the goal of simultaneously facilitating the LMCT process and addressing the issue of photocatalyst recovery.Remarkably,the iron-based ionic liquid 1-butyl-3-methylimidazolium tetrachloroferrate(C_(4)mim-Fe Cl_(4))demonstrates exceptional recyclability and stability for the photocatalytic hydroacylation of olefins.This study will pave the way for new approaches to photocatalytic organic synthesis using ionic liquids as recyclable photocatalysts. 展开更多
关键词 LMCT Ionic liquids homogeneous catalysis Heterogeneous separation Recyclable photocatalysts
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Modified Near‑Infrared Annealing Enabled Rapid and Homogeneous Crystallization of Perovskite Films for Efficient Solar Modules
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作者 Qing Chang Peng He +10 位作者 Haosong Huang Yingchen Peng Xiao Han Yang Shen Jun Yin Zhengjing Zhao Ye Yang Binghui Wu Zhiguo Zhao Jing Li Nanfeng Zheng 《Nano-Micro Letters》 2025年第11期236-250,共15页
Currently,perovskite solar cells have achieved commendable progresses in power conversion efficiency(PCE)and operational stability.However,some conventional laboratory-scale fabrication methods become challenging when... Currently,perovskite solar cells have achieved commendable progresses in power conversion efficiency(PCE)and operational stability.However,some conventional laboratory-scale fabrication methods become challenging when scaling up material syntheses or device production.Particularly,the prolonged high-temperature annealing process for the crystallization of perovskites requires a substantial amount of energy consumption and impact the modules’throughput.Here,we report a modified near-infrared annealing(NIRA)process,which involves the excess PbI_(2)engineered crystallization,efficiently reduces the preparation time for perovskite active layer to within 20 s compared to dozens of min in conventional hot plate annealing(HPA)process.The study showed that the incorporated PbI_(2)promoted the consistent nucleation of the perovskite film,leading to the subsequent rapid and homogeneous crystallization at the NIRA stage.Thus,highly crystalized perovskite film was realized with even better crystallization performance than conventional HPA-based film.Ultimately,efficient perovskite solar modules of 36 and 100 cm^(2)were readily fabricated with the optimal PCEs of 22.03%and 20.18%,respectively.This study demonstrates,for the first time,the successful achievement of homogeneous and high-quality crystallization in large-area perovskite films through rapid NIRA processing.This approach not only significantly reduces energy consumption during production,but also substantially shortens the manufacturing cycle,paving a new path toward the commercial-scale application of perovskite solar modules. 展开更多
关键词 Near-infrared annealing homogeneous crystallization Blade coating Perovskite solar modules
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A General Association Test for High-Dimensional Random Vectors
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作者 Yongshuai Chen Peng Lin Baoxue Zhang 《Acta Mathematica Sinica,English Series》 2025年第9期2400-2440,共41页
Testing the association of two high-dimensional random vectors is of fundamental importance in the statistical theory and applications.In this paper,we propose a new test statistic based on the Frobenius norm and subt... Testing the association of two high-dimensional random vectors is of fundamental importance in the statistical theory and applications.In this paper,we propose a new test statistic based on the Frobenius norm and subtracting bias technique,which is generally applicable to high-dimensional data without restricting the distributional Assumptions.The limiting null distribution of the proposed test is shown to be a random variable combining a finite chi-squared-type mixture with a normal approximation.Our proposed test method can also be a normal approximation or a finite chi-squared-type mixtures under additional regularity conditions.To make the test statistic applicable,we introduce a wild bootstrap method and demonstrate its validity.The finite-sample performance of the proposed test via Monte Carlo simulations reveals that it performs better at controlling the empirical size than some existing tests,even when the normal approximation is invalid.Real data analysis is devoted to illustrating the proposed test. 展开更多
关键词 Association test high dimension Chi-squared-type mixtures wild bootstrap
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HAUSDORFF DIMENSION OF RECURRENCE SETS FOR MATRIX TRANSFORMATIONS OF TORI
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作者 Zhangnan HU Bing LI 《Acta Mathematica Scientia》 2025年第4期1659-1673,共15页
Let T:T^(d)→T^(d),defined by Tx=AX(mod 1),where A is a d×d integer matrix with eigenvalues 1<|λ_(1)|≤|λ_(2)|≤…≤|λ_(d)|,We investigate the Hausdorff dimension of the recurrence set R(ψ)={x∈T^(d):T^(n)... Let T:T^(d)→T^(d),defined by Tx=AX(mod 1),where A is a d×d integer matrix with eigenvalues 1<|λ_(1)|≤|λ_(2)|≤…≤|λ_(d)|,We investigate the Hausdorff dimension of the recurrence set R(ψ)={x∈T^(d):T^(n)x∈B(x,ψ(n))for infinitely many n}forα≥log|λ_(d)/λ_(1)|,whereψis a positive decreasing function defined onℕand its lower order at infinity isα=lim inf_(n→∞)-logψ(n)/n.In the case that A is diagonalizable overℚwith integral eigenvalues,we obtain the dimension formula. 展开更多
关键词 quantitative recurrence properties Hausdorff dimension matrix transformations
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Research on Dimension Analysis of Spectative Buildings Based on Fractal Theory
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作者 Yunyang Zheng Jiayao Zhu +1 位作者 Jingjing Guo Hao Hu 《Journal of Architectural Research and Development》 2025年第4期71-76,共6页
Based on the fractal theory,this paper takes the form of performing architecture as the research object,and systematically discusses the application value of fractal dimension in architectural design.By expounding the... Based on the fractal theory,this paper takes the form of performing architecture as the research object,and systematically discusses the application value of fractal dimension in architectural design.By expounding the self-affine,self-similarity,and iterative generation characteristics of fractal geometry,the Box-Counting Dimension method is introduced as a quantitative tool to measure the dimensions of the roof plane,facade,and spatial shape of Wuzhen Grand Theatre and Harbin Grand Theatre.The research shows that the geometric complexity of Wuzhen Grand Theater in the“fifth façade”and multi-faceted façade is significantly higher than that of Harbin Grand Theater,and its morphological design is more inclined to echo the texture of the surrounding water towns.The Harbin Grand Theater realizes the dialogue with the natural environment with simple nonlinear lines.The research proves that fractal dimension can effectively quantify the complexity of architectural form,provide a scientific basis for the form design,environmental integration,and form interpretation of performance architecture,and expand the mathematical analysis dimension of architectural form design. 展开更多
关键词 Fractal dimension Fractal geometry Performing architecture Architectural form Architectural design
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An intelligent algorithm to fast and accurately detect chaotic correlation dimension
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作者 Mengyan Shen Miaomiao Ma +1 位作者 Zhicheng Su Xuejun Zhang 《River》 2025年第2期253-264,共12页
Detecting the complexity of natural systems,such as hydrological systems,can help improve our understanding of complex interactions and feedback between variables in these systems.The correlation dimension method,as o... Detecting the complexity of natural systems,such as hydrological systems,can help improve our understanding of complex interactions and feedback between variables in these systems.The correlation dimension method,as one of the most useful methods,has been applied in many studies to investigate the chaos and detect the intrinsic dimensions of underlying dynamic systems.However,this method often relies on manual inspection due to uncertainties from iden-tifying the scaling region,making the correlation dimension value calculation troublesome and subjective.Therefore,it is necessary to propose a fast and intelligent algorithm to solve the above problem.This study implies the distinct windows tracking technique and fuzzy C-means clustering algorithm to accu-rately identify the scaling range and estimate the correlation dimension values.The proposed method is verified using the classic Lorenz chaotic system and 10 streamflow series in the Daling River basin of Liaoning Province,China.The results reveal that the proposed method is an intelligent and robust method for rapidly and accurately calculating the correlation dimension values,and the average operation efficiency of the proposed algorithm is 30 times faster than that of the original Grassberger-Procaccia algorithm. 展开更多
关键词 chaotic time series correlation dimension distinct windows tracking fuzzy C-means clustering
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Cooperative Metaheuristics with Dynamic Dimension Reduction for High-Dimensional Optimization Problems
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作者 Junxiang Li Zhipeng Dong +2 位作者 Ben Han Jianqiao Chen Xinxin Zhang 《Computers, Materials & Continua》 2026年第1期1484-1502,共19页
Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when ta... Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems. 展开更多
关键词 dimension reduction modified principal components analysis high-dimensional optimization problems cooperative metaheuristics metaheuristic algorithms
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Digital reconstruction of three-dimensional contours and its application to microstructural evaluation of postblast rock fissure surfaces
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作者 Yanbing Wang Zhaoyang Wang +1 位作者 Dairui Fu Mingwei Gang 《Deep Underground Science and Engineering》 2025年第2期316-328,共13页
Fracture surface contour study is one of the important requirements for characterization and evaluation of the microstructure of rocks.Based on the improved cube covering method and the 3D contour digital reconstructi... Fracture surface contour study is one of the important requirements for characterization and evaluation of the microstructure of rocks.Based on the improved cube covering method and the 3D contour digital reconstruction model,this study proposes a quantitative microstructure characterization method combining the roughness evaluation index and the 3D fractal dimension to study the change rule of the fracture surface morphology after blasting.This method was applied and validated in the study of the fracture microstructure of the rock after blasting.The results show that the fracture morphology characteristics of the 3D contour digital reconstruction model have good correlation with the changes of the blasting action.The undulation rate of the three-dimensional surface profile of the rock is more prone to dramatic rise and dramatic fall morphology.In terms of tilting trend,the tilting direction also shows gradual disorder,with the tilting angle increasing correspondingly.All the roughness evaluation indexes of the rock fissure surface after blasting show a linear and gradually increasing trend as the distance to the bursting center increases;the difference between the two-dimensional roughness evaluation indexes and the three-dimensional ones of the same micro-area rock samples also becomes increasingly larger,among which the three-dimensional fissure roughness coefficient JRC and the surface roughness ratio Rs display better correlation.Compared with the linear fitting formula of the power function relationship,the three-dimensional fractal dimension of the postblast fissure surface is fitted with the values of JRC and Rs,which renders higher correlation coefficients,and the degree of linear fitting of JRC to the three-dimensional fractal dimension is higher.The fractal characteristics of the blast-affected region form a unity with the three-dimensional roughness evaluation of the fissure surface. 展开更多
关键词 cube covering method evaluation of damage characterization fractal dimension roughness three-dimensional contour scanning
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Influence of Fractal Dimension on Gas-Driven Two-Phase Flow in Fractal Porous Media:A VOF Model-Based Simulation
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作者 Xiaolin Wang Richeng Liu +3 位作者 Kai Qiu Zhongzhong Liu Shisen Zhao Shuchen Li 《Computer Modeling in Engineering & Sciences》 2025年第7期289-307,共19页
Gas-liquid two-phase flow in fractal porous media is pivotal for engineering applications,yet it remains challenging to be accurately characterized due to complex microstructure-flow interactions.This study establishe... Gas-liquid two-phase flow in fractal porous media is pivotal for engineering applications,yet it remains challenging to be accurately characterized due to complex microstructure-flow interactions.This study establishes a pore-scale numerical framework integratingMonte Carlo-generated fractal porousmedia with Volume of Fluid(VOF)simulations to unravel the coupling among pore distribution characterized by fractal dimension(Df),flow dynamics,and displacement efficiency.A pore-scale model based on the computed tomography(CT)microstructure of Berea sandstone is established,and the simulation results are compared with experimental data.Good agreement is found in phase distribution,breakthrough behavior,and flow path morphology,confirming the reliability of the numerical simulation method.Ten fractal porous media models with Df ranging from 1.25~1.7 were constructed using a Monte-Carlo approach.The gas-liquid two-phase flow dynamics was characterized using the VOF solver across gas injection rates of 0.05-5m/s,inwhich the time-resolved two-phase distribution patternswere systematically recorded.The results reveal that smaller fractal dimensions(Df=1.25~1.45)accelerate fingering breakthrough(peak velocity is 1.73 m/s at Df=1.45)due to a bimodal pore size distribution dominated by narrow channels.Increasing Df amplifies vorticity generation by about 3 times(eddy viscosity is 0.033 Pa⋅s at Df=1.7)through reduced interfacial curvature,while tortuosity-driven pressure differentials transition from sharp increases(0.4~6.3 Pa at Df=1.25~1.3)to inertial plateaus(4.8 Pa at Df=1.7).A nonlinear increase in equilibrium gas volume fraction(fav=0.692 at Df=1.7)emerges from residual gas saturation and turbulence-enhanced dispersion.This behavior is further modulated by flow velocity,with fav peaking at 0.72 under capillary-dominated conditions(0.05 m/s),but decreasing to 0.65 in the inertial regime(0.5 m/s).The work quantitatively links fractal topology to multiphase flow regimes,demonstrating the critical role of Df in governing preferential pathways,energy dissipation,and phase distribution. 展开更多
关键词 Fractal porous media gas-liquid two-phase flow fractal dimension vortex evolution VOF model displacement efficiency
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A Three-Dimensional Study on the Deep Integration of Excellent Traditional Chinese Culture with University Ideological and Political Courses-Guided by the“Two Integrations”Methodology
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作者 Yanyang Lu 《Journal of Contemporary Educational Research》 2025年第9期413-419,共7页
Against the backdrop of intensified global cultural collisions and ideological competition,deeply integrating excellent traditional Chinese culture(ETCC)into university ideological and political courses(IPCs)has becom... Against the backdrop of intensified global cultural collisions and ideological competition,deeply integrating excellent traditional Chinese culture(ETCC)into university ideological and political courses(IPCs)has become an imperative of our times.Guided by General Secretary Xi Jinping’s methodology of“Two Integrations,”this paper examines the pathways for this integration from three dimensions:value,theory,and practice.The value dimension emphasizes fostering moral conviction and strengthening the spiritual foundation to meet needs such as safeguarding cultural security,preserving the spiritual lineage,and constructing a spiritual framework.The theoretical dimension reveals the mutually constitutive breakthroughs between Marxism and traditional Chinese dialectical thinking,encompassing methodological complementarity,logical coherence of values,and discursive system innovation.The practical dimension involves constructing a comprehensive educational ecosystem by localizing teaching content,modernizing traditional resources,and fostering inter-platform collaborative education,thereby internalizing the value of traditional culture.These three dimensions synergize and co-constitute each other,collectively providing methodological support and practical paradigms for cultivating cultural confidence among youth and forging a new generation capable of shouldering the mission of national rejuvenation. 展开更多
关键词 Excellent traditional Chinese culture University ideological and political courses Two integrations Deep integration Three dimensions
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Exploring High Dimensional Feature Space With Channel-Spatial Nonlinear Transforms for Learned Image Compression
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作者 Wen Tan Fanyang Meng +2 位作者 Chao Li Youneng Bao Yongsheng Liang 《CAAI Transactions on Intelligence Technology》 2025年第4期1235-1253,共19页
Nonlinear transforms have significantly advanced learned image compression(LIC),particularly using residual blocks.This transform enhances the nonlinear expression ability and obtain compact feature representation by ... Nonlinear transforms have significantly advanced learned image compression(LIC),particularly using residual blocks.This transform enhances the nonlinear expression ability and obtain compact feature representation by enlarging the receptive field,which indicates how the convolution process extracts features in a high dimensional feature space.However,its functionality is restricted to the spatial dimension and network depth,limiting further improvements in network performance due to insufficient information interaction and representation.Crucially,the potential of high dimensional feature space in the channel dimension and the exploration of network width/resolution remain largely untapped.In this paper,we consider nonlinear transforms from the perspective of feature space,defining high-dimensional feature spaces in different dimensions and investigating the specific effects.Firstly,we introduce the dimension increasing and decreasing transforms in both channel and spatial dimensions to obtain high dimensional feature space and achieve better feature extraction.Secondly,we design a channel-spatial fusion residual transform(CSR),which incorporates multi-dimensional transforms for a more effective representation.Furthermore,we simplify the proposed fusion transform to obtain a slim architecture(CSR-sm),balancing network complexity and compression performance.Finally,we build the overall network with stacked CSR transforms to achieve better compression and reconstruction.Experimental results demonstrate that the proposed method can achieve superior ratedistortion performance compared to the existing LIC methods and traditional codecs.Specifically,our proposed method achieves 9.38%BD-rate reduction over VVC on Kodak dataset. 展开更多
关键词 high dimensional feature space learned image compression nonlinear transform the dimension increase and decrease
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ESTIMATES OF ALL TERMS OF HOMOGENEOUS POLYNOMIAL EXPANSIONS FOR THE SUBCLASSES OF G-PARAMETRIC STARLIKE MAPPINGS OF COMPLEX ORDER IN SEVERAL COMPLEX VARIABLES
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作者 Liangpeng XIONG Qingchao WANG Xiaoying SIMA 《Acta Mathematica Scientia》 2025年第4期1555-1566,共12页
In this paper,the class of starlike functions of complex order γ(γ∈ℂ−{0})is extended from the case on unit disk U=(z∈C:|z|<1)to the case on the unit ball B in a complex Banach space or the unit polydisk U^(n) i... In this paper,the class of starlike functions of complex order γ(γ∈ℂ−{0})is extended from the case on unit disk U=(z∈C:|z|<1)to the case on the unit ball B in a complex Banach space or the unit polydisk U^(n) in C^(n).Let g be a convex function in U. We mainly establish the sharp bounds of all terms of homogeneous polynomial expansions for a subclass of g-parametric starlike mappings of complex order γ on B (resp.U^(n))when the mappings f are k-fold symmetric, k ∈ N. Our results partly solve the Bieberbach conjecture in several complex variables and generalize some prior works. 展开更多
关键词 class starlike functions complex order g parametric starlike mappings unit polydisk bieberbach co convex function homogeneous polynomial expansions banach space
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π-π2max:Bridging molecular characteristics to crystal packing in nitro-containing two-dimensional energetic materials
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作者 Xiaokai He Chao Chen +4 位作者 Zhixiang Zhang Linyuan Wen Yiding Ma Yilin Cao Yingzhe Liu 《Defence Technology(防务技术)》 2025年第7期192-202,共11页
Two-dimensional energetic materials(2DEMs),characterized by their exceptional interlayer sliding properties,are recognized as exemplar of low-sensitivity energetic materials.However,the diversity of available 2DEMs is... Two-dimensional energetic materials(2DEMs),characterized by their exceptional interlayer sliding properties,are recognized as exemplar of low-sensitivity energetic materials.However,the diversity of available 2DEMs is severely constrained by the absence of efficient methods for rapidly predicting crystal packing modes from molecular structures,impeding the high-throughput rational design of such materials.In this study,we employed quantified indicators,such as hydrogen bond dimension and maximum planar separation,to quickly screen 172DEM and 16 non-2DEM crystal structures from a crystal database.They were subsequently compared and analyzed,focusing on hydrogen bond donor-acceptor combinations,skeleton features,and intermolecular interactions.Our findings suggest that theπ-πpacking interaction energy is a key determinant in the formation of layered packing modes by planar energetic molecules,with its magnitude primarily influenced by the strongest dimericπ-πinteraction(π-π2max).Consequently,we have delineated a critical threshold forπ-π2max to discern layered packing modes and formulated a theoretical model for predictingπ-π2max,grounded in molecular electrostatic potential and dipole moment analysis.The predictive efficacy of this model was substantiated through external validation on a test set comprising 31 planar energetic molecular crystals,achieving an accuracy of 84%and a recall of 75%.Furthermore,the proposed model shows superior classification predictive performance compared to typical machine learning methods,such as random forest,on the external validation samples.This contribution introduces a novel methodology for the identification of crystal packing modes in 2DEMs,potentially accelerating the design and synthesis of high-energy,low-sensitivity 2DEMs. 展开更多
关键词 Two-dimensionalenergeticmaterials Maximum planar separation Hydrogen bond dimension Hydrogen bond donor-acceptor π-πinteraction energy prediction Crystal packing modes identification
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Managing Multidimensional International World With Spatial Grasp Model
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作者 Peter Simon Sapaty 《International Relations and Diplomacy》 2025年第5期257-269,共13页
“Multidimensional international world”refers to understanding the world through multiple dimensions beyond traditional economic or political measures,fostering cross-cultural collaboration,and creating systems that ... “Multidimensional international world”refers to understanding the world through multiple dimensions beyond traditional economic or political measures,fostering cross-cultural collaboration,and creating systems that balance global integration with local needs.This also includes management of global business operations across diverse cultures in a multipolar international landscape.The paper briefs the developed and already tested in numerous applications high-level Spatial Grasp Model and Technology(SGT),which can help investigate and manage complex systems with a holistic spatial approach effectively covering various physical and virtual dimensions,their interrelations,and integration as a whole.Different areas will be investigated with examples of practical solutions in them and their combinations in a high-level Spatial Grasp Language(SGL),the key element of SGT.This allows for the creation and distributed management of very large spatial networks with different orientation which can be self-spreading,self-analyzing,self-modifying,and self-recovering in complex terrestrial and celestial environments,and also organize dynamic multi-networking solutions supporting global evolution and integrity. 展开更多
关键词 multidimensional world Spatial Grasp Technology Spatial Grasp Language distributed network operations dimensions investigation and management collective spatial solutions global integrity
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Parameterized Littlewood-Paley Operators and Their Commutators on Two-Weight Grand Homogeneous Variable Herz-Morrey Spaces
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作者 Xijuan CHEN Wenwen TAO Guanghui LU 《Journal of Mathematical Research with Applications》 2025年第2期231-242,共12页
In this paper,the authors prove that the parameterized area integralμ_(Ω,S)^(ρ)and the parameterized Littlewood-Paley g_(δ)^(*)-functionμ_(Ω,δ)^(*,ρ)are bounded on two-weight grand homogeneous variable Herz-Mo... In this paper,the authors prove that the parameterized area integralμ_(Ω,S)^(ρ)and the parameterized Littlewood-Paley g_(δ)^(*)-functionμ_(Ω,δ)^(*,ρ)are bounded on two-weight grand homogeneous variable Herz-Morrey spaces MK_(p),θ,q(·))^(α(·),λ)(ω_(1),ω_(2)),where θ>0,λ∈(2,∞),q(·)∈B(R^(n)),α(·)∈L^(∞)(R^(n)),ω_(1)∈A_(p_(ω_(1)))for p_(ω_(1))∈[1,∞]and ω_(2) is a weight.Furthermore,the authors prove that the commutators[b,μ_(Ω,S)^(ρ)]which is formed by b∈BMO(R^(n))and the μ_(Ω,S)^(ρ),and the[b,μ_(Ω,δ)^(*,ρ)]generated by b∈BMO(R^(n))and theμ_(Ω,δ)^(*,ρ)are bounded on MK_(p),θ,q(·))^(α(·),λ)(ω_(1),ω_(2)),respectively. 展开更多
关键词 Grand homogeneous variable Herz-Morrey space parameterized area integral parameterized Littlewood-Paley g_(δ)^(*)-function commutator space BMO(R^(n))
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YOLO-SIFD:YOLO with Sliced Inference and Fractal Dimension Analysis for Improved Fire and Smoke Detection
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作者 Mariam Ishtiaq Jong-Un Won 《Computers, Materials & Continua》 2025年第3期5343-5361,共19页
Fire detection has held stringent importance in computer vision for over half a century.The development of early fire detection strategies is pivotal to the realization of safe and smart cities,inhabitable in the futu... Fire detection has held stringent importance in computer vision for over half a century.The development of early fire detection strategies is pivotal to the realization of safe and smart cities,inhabitable in the future.However,the development of optimal fire and smoke detection models is hindered by limitations like publicly available datasets,lack of diversity,and class imbalance.In this work,we explore the possible ways forward to overcome these challenges posed by available datasets.We study the impact of a class-balanced dataset to improve the fire detection capability of state-of-the-art(SOTA)vision-based models and propose the use of generative models for data augmentation,as a future work direction.First,a comparative analysis of two prominent object detection architectures,You Only Look Once version 7(YOLOv7)and YOLOv8 has been carried out using a balanced dataset,where both models have been evaluated across various evaluation metrics including precision,recall,and mean Average Precision(mAP).The results are compared to other recent fire detection models,highlighting the superior performance and efficiency of the proposed YOLOv8 architecture as trained on our balanced dataset.Next,a fractal dimension analysis gives a deeper insight into the repetition of patterns in fire,and the effectiveness of the results has been demonstrated by a windowing-based inference approach.The proposed Slicing-Aided Hyper Inference(SAHI)improves the fire and smoke detection capability of YOLOv8 for real-life applications with a significantly improved mAP performance over a strict confidence threshold.YOLOv8 with SAHI inference gives a mAP:50-95 improvement of more than 25%compared to the base YOLOv8 model.The study also provides insights into future work direction by exploring the potential of generative models like deep convolutional generative adversarial network(DCGAN)and diffusion models like stable diffusion,for data augmentation. 展开更多
关键词 Fire detection smoke detection class-balanced dataset you only look once(YOLO) slicing-aided hyper inference(SAHI) fractal dimension generative adversarial network(GAN) diffusion models
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Validation of Dimensionless Parameters for Distinguishing between Homogeneous and Bubbling Fluidizations
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作者 Kenya Kuwagi Atsuto Kogane +1 位作者 Yui Sasaki Hiroyuki Hirano 《Open Journal of Fluid Dynamics》 2021年第2期81-97,共17页
The difference between homogeneous and bubbling fluidization behaviors has been studied for the past 70 years, where several researchers have reported on the influence of interparticle forces in fluidization. Although... The difference between homogeneous and bubbling fluidization behaviors has been studied for the past 70 years, where several researchers have reported on the influence of interparticle forces in fluidization. Although interparticle forces such as van der Waals forces are evident in a real system, these forces are not the determinant in homogeneous fluidization, which can be simulated without any interparticle forces. In our previous study, the difference in fundamental mechanisms of the two fluidization states was analytically determined with a dimensionless gravity term, comprising the Reynolds number, Archimedes number, and density ratio. Nevertheless, some researchers insist that interparticle forces are dominant and a hydrodynamic force is not dominant. In this study, a dimensional analysis was applied to obtain a dominant parameter for distinguishing two fluidizations. Furthermore, some parameters were examined by comparing the experimental data in previous studies. The results indicated that hydrodynamic force is the dominant factor and the dimensionless gravity term is the dominant parameter in differentiating the two fluidized states. 展开更多
关键词 Bubbling Fluidization homogeneous Fluidization Aggregative PARTICULATE dimensional Analysis
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Experimental investigation of methane explosion fracturing in bedding shales:Load characteristics and three-dimensional fracture propagation 被引量:2
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作者 Yu Wang Cheng Zhai +5 位作者 Ting Liu Jizhao Xu Wei Tang Yangfeng Zheng Xinyu Zhu Ning Luo 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第10期1365-1383,共19页
Methane in-situ explosion fracturing(MISEF)enhances permeability in shale reservoirs by detonating desorbed methane to generate detonation waves in perforations.Fracture propagation in bedding shale under varying expl... Methane in-situ explosion fracturing(MISEF)enhances permeability in shale reservoirs by detonating desorbed methane to generate detonation waves in perforations.Fracture propagation in bedding shale under varying explosion loads remains unclear.In this study,prefabricated perforated shale samples with parallel and vertical bedding are fractured under five distinct explosion loads using a MISEF experimental setup.High-frequency explosion pressure-time curves were monitored within an equivalent perforation,and computed tomography scanning along with three-dimensional reconstruction techniques were used to investigate fracture propagation patterns.Additionally,the formation mechanism and influencing factors of explosion crack-generated fines(CGF)were clarified by analyzing the morphology and statistics of explosion debris particles.The results indicate that methane explosion generated oscillating-pulse loads within perforations.Explosion characteristic parameters increase with increasing initial pressure.Explosion load and bedding orientation significantly influence fracture propagation patterns.As initial pressure increases,the fracture mode transitions from bi-wing to 4–5 radial fractures.In parallel bedding shale,radial fractures noticeably deflect along the bedding surface.Vertical bedding facilitates the development of transverse fractures oriented parallel to the cross-section.Bifurcation-merging of explosioninduced fractures generated CGF.CGF mass and fractal dimension increase,while average particle size decreases with increasing explosion load.This study provides valuable insights into MISEF technology. 展开更多
关键词 Methane in-situ explosion fracturing Bedding shale Fracture propagation Three-dimensional reconstruction Crack-generated fines Fractal dimension
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