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Interscale analysis of sediment clusters amid turbulence 被引量:1
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作者 Wai Hong Ronald Chan Ahmed Elnahhas +3 位作者 Hanul Hwang Lucy J.Brown Andrew J.Banko S.Balachandar 《Acta Mechanica Sinica》 2026年第1期73-80,共8页
Noncohesive particle clusters are identified and tracked in turbulent flows to determine the breakdown and time evolution of cluster statistics and their implications for interscale mass transfer,which has connections... Noncohesive particle clusters are identified and tracked in turbulent flows to determine the breakdown and time evolution of cluster statistics and their implications for interscale mass transfer,which has connections to the classical turbulent energy cascade and its mass cascade counterpart running in parallel.In particular,the formation and dynamics of sediment and larvae clusters are of interest to coral larvae settlement in coastal regions and particularly the resilience of green-gray coastal protection solutions.Analogous cluster behavior is relevant to cloud microphysics and precipitation initiation,radiation transport and light transmission through colloids and suspensions,heat and mass transfer in particle-laden flows,and viral and pollutant transmission.Following a comparison between various clustering techniques,we adopt a density-based cluster identification algorithm based on its simplicity and efficiency,where particles are clustered based on the number of neighboring particles in their individual spheres of influence.We establish parallels with lattice-based percolation theory,as evident in the power-law scaling of the cluster size distribution near the percolation threshold.The degree of discontinuity of the phase transition associated with this percolation threshold is observed to broaden with larger Stokes numbers and thereby large-scale clustering.The sensitivity of our findings to the employed clustering algorithm is discussed.A novel cluster tracking algorithm is deployed to determine the interscale transfer rate along the particle-number phase-space dimension via accounting of cluster breakup and merger events,extending previous work on the bubble breakup cascade beneath surface breaking waves.Our findings shed light on the interaction between particle clusters and their carrier turbulent flows,with an eye toward transport models incorporating cluster characteristics and dynamics. 展开更多
关键词 Particle-laden flows Particle-laden turbulence Sediment transport Computational fluid dynamics Multiphase turbulence Particle clustering Percolation theory
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Ligand-directed construction of cobalt-oxo cluster-based organic frameworks:Structural modulation,semiconductor,and antiferromagnetic properties
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作者 SHI Jinlian LIU Xiaoru XU Zhongxuan 《无机化学学报》 北大核心 2026年第1期45-54,共10页
Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully construct... Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully constructed by coordinatively assembling the semi-rigid multidentate ligand 5-(1-carboxyethoxy)isophthalic acid(H₃CIA)with the Nheterocyclic ligands 1,4-di(4H-1,2,4-triazol-4-yl)benzene(1,4-dtb)and 1,4-di(1H-imidazol-1-yl)benzene(1,4-dib),respectively,around Co^(2+)ions.Single-crystal X-ray diffraction analysis revealed that in both complexes HU23 and HU24,the CIA^(3-)anions adopt aκ^(7)-coordination mode,bridging six Co^(2+)ions via their five carboxylate oxygen atoms and one ether oxygen atom.This linkage forms tetranuclear[Co4(μ3-OH)2]^(6+)units.These Co-oxo cluster units were interconnected by CIA^(3-)anions to assemble into 2D kgd-type structures featuring a 3,6-connected topology.The 2D layers were further connected by 1,4-dtb and 1,4-dib,resulting in 3D pillar-layered frameworks for HU23 and HU24.Notably,despite the similar configurations of 1,4-dtb and 1,4-dib,differences in their coordination spatial orientations lead to topological divergence in the 3D frameworks of HU23 and HU24.Topological analysis indicates that the frameworks of HU23 and HU24 can be simplified into a 3,10-connected net(point symbol:(4^(10).6^(3).8^(2))(4^(3))_(2))and a 3,8-connected tfz-d net(point symbol:(4^(3))_(2)((4^(6).6^(18).8^(4)))),respectively.This structural differentiation confirms the precise regulatory role of ligands on the topology of metal-organic frameworks.Moreover,the ultraviolet-visible absorption spectra confirmed that HU23 and HU24 have strong absorption capabilities for ultraviolet and visible light.According to the Kubelka-Munk method,their bandwidths were 2.15 and 2.08 eV,respectively,which are consistent with those of typical semiconductor materials.Variable-temperature magnetic susceptibility measurements(2-300 K)revealed significant antiferromagnetic coupling in both complexes,with their effective magnetic moments decreasing markedly as the temperature lowered.CCDC:2457554,HU23;2457553,HU24. 展开更多
关键词 semi-rigid carboxylic acid ligands three-dimensional framework tetranuclear cobalt-oxo cluster semiconductor material antiferromagnetic magnetism
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Progress in clustering algorithms for astronomical spectra over a decade
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作者 Jianing Tian Haifeng Yang +4 位作者 Jianghui Cai Yuqing Yang Xiangru Li Zhenping Yi Lili Wang 《Astronomical Techniques and Instruments》 2026年第1期10-25,共16页
As large-scale astronomical surveys,such as the Sloan Digital Sky Survey(SDSS)and the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),generate increasingly complex datasets,clustering algorithms have... As large-scale astronomical surveys,such as the Sloan Digital Sky Survey(SDSS)and the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),generate increasingly complex datasets,clustering algorithms have become vital for identifying patterns and classifying celestial objects.This paper systematically investigates the application of five main categories of clustering techniques-partition-based,density-based,model-based,hierarchical,and“others”-across a range of astronomical research over the past decade.This review focuses on the six key application areas of stellar classification,galaxy structure analysis,detection of galactic and interstellar features,highenergy astrophysics,exoplanet studies,and anomaly detection.This paper provides an in-depth analysis of the performance and results of each method,considering their respective suitabilities for different data types.Additionally,it presents clustering algorithm selection strategies based on the characteristics of the spectroscopic data being analyzed.We highlight challenges such as handling large datasets,the need for more efficient computational tools,and the lack of labeled data.We also underscore the potential of unsupervised and semi-supervised clustering approaches to overcome these challenges,offering insight into their practical applications,performance,and results in astronomical research. 展开更多
关键词 clusterING Stellar types Astronomical techniques CLASSIFICATION GALAXIES
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Systematic study of laser-assisted cluster radioactivity for deformed nuclei
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作者 Leng-Jun Liao Lin-Jing Qi +2 位作者 Xi-Jun Wu Xiao-Hua Li Ming Li 《Nuclear Science and Techniques》 2026年第4期232-242,共11页
In this study,the effects of laser fields that can be achieved in the near future on cluster penetration probability and half-life are quantitatively investigated.The calculation results show that extreme laser fields... In this study,the effects of laser fields that can be achieved in the near future on cluster penetration probability and half-life are quantitatively investigated.The calculation results show that extreme laser fields can slightly change the cluster-decay half-life by affecting the penetration probability within a narrow range.Subsequently,we discuss the correlation between the change rate of the penetration probability and the tunneling path.The results indicate that for different parent nuclei emitting the same cluster,nuclei with longer tunneling paths are more easily affected by the laser fields.The shell effect on this correlation is also observed.In addition,the impact of laser fields on the penetration probability in any direction is investigated. 展开更多
关键词 cluster radioactivity HALF-LIFE Extreme laser field Penetration probability
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Multi-affinity clustering analysis based graph learning for multichannel signal utilization
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作者 WANG Zhicheng JIANG Huiming +2 位作者 XU Hui SUN Gao SHENG Jialian 《Journal of Systems Engineering and Electronics》 2026年第1期171-183,共13页
Multichannel signals have the characteristics of information diversity and information consistency.To better explore and utilize the affinity relationship within multichannel signals,a new graph learning technique bas... Multichannel signals have the characteristics of information diversity and information consistency.To better explore and utilize the affinity relationship within multichannel signals,a new graph learning technique based on low rank tensor approximation is proposed for multichannel monitoring signal processing and utilization.Firstly,the affinity relationship of multichannel signals can be acquired based on the clustering results of each channel signal.Wherein an affinity tensor is constructed to integrate the diverse and consistent information of the clustering information among multichannel signals.Secondly,a low-rank tensor optimization model is built and the joint affinity matrix is optimized with the assistance of the strong confidence affinity matrix.Through solving the optimization model,the fused affinity relationship graph of multichannel signals can be obtained.Finally,the multichannel fused clustering results can be acquired though the updated joint affinity relationship graph.The multichannel signal utilization examples in health state assessment with public datasets and microwave detection with actual echoes verify the advantages and effectiveness of the proposed method. 展开更多
关键词 clustering analysis multichannel signals health state assessment target recognition
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Ion-cluster-optimized microphase separation in shape-memory polydisulfides for enhanced mechanical performance
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作者 Chengyuan Yu Huiyao Lin +5 位作者 Le Li Ruirui Gu Qi Zhang Chenyu Shi Chenchen Zhang Fei Tong 《Chinese Chemical Letters》 2026年第2期494-500,共7页
Developing advanced polymeric materials with enhanced mechanical properties and functionalities has been a long-standing goal in materials science.Recently,supramolecular polymeric materials(SPMs)have drawn increased ... Developing advanced polymeric materials with enhanced mechanical properties and functionalities has been a long-standing goal in materials science.Recently,supramolecular polymeric materials(SPMs)have drawn increased attention due to their unique properties and potential applications in self-healing,shape memory,sensors,and flexible electronics.Here,we develop an ionic cluster-optimized microphase separation strategy to enhance the toughening and energy dissipation capabilities of polydisulfide-based supramolecular polymers.The mechanical properties,including Young's modulus and toughness,are significantly improved by integrating the quadruple H-bonding 2-ureido-4-pyrimidone(UPy)induced microphase separation with iron(III)-to-carboxylate ionic clusters.By combining established chemical approaches with adjustable polymer phase ratios,it is revealed that the synergistic effect of these factors expands the interchain spacing,facilitates the formation of microphase domains,and enhances the tolerance of polythioctic acid-based polymers to external mechanical and thermal stimuli,meeting the practical requirements for industrial plastic applications.Moreover,the UPy-functionalized polymers incorporating iron carboxylate clusters exhibit good one-way shape memory behavior with practical applicability at a relatively low recovery temperature.Our work demonstrates a novel strategy for constructing industrially viable shape memory dynamic SPMs and paves the way for future innovations in developing SPMs. 展开更多
关键词 Polydisulfides Network toughening lonic clusters Microphase separation Shape-memory supramolecular polymers
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Evolution Characteristics and Driving Mechanism of‘Bottom-up’and‘Top-down’Endogenous Automobile Industry Clusters:A Comparative Study in Taizhou and Wuhu,China
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作者 JIANG Haining ZHANG Jun +1 位作者 CHEN Jiaqi JIN Xingxing 《Chinese Geographical Science》 2026年第1期34-49,共16页
Bottom-up and top-down endogenous automobile clusters exhibit distinct evolutionary traits and driving mechanisms,yet their comparative analysis remains understudied.Therefore,using Taizhou automobile industry cluster... Bottom-up and top-down endogenous automobile clusters exhibit distinct evolutionary traits and driving mechanisms,yet their comparative analysis remains understudied.Therefore,using Taizhou automobile industry cluster(TAIC)and Wuhu automobile industry cluster(WAIC)as cases,using historical statistical data and field interview data from the 1980s to 2023,combined with qualitative research methods of thematic and diachronic analysis,and quantitative research methods of social network analysis,we compare both endogenous automobile clusters’evolutionary traits and driving mechanisms.The results confirm both clusters undergo multi-scale spatial reconfiguration,organizational complexification,and intelligent networking technological transformation,yet diverge fundamentally:TAIC evolves through market-driven progressive expansion,transitioning from single to dual-core structures via private enterprise networking,with innovation following market-integrated logic and institutional thickness built on demand-driven evolution.Conversely,WAIC follows planned expansion,maintaining state-led hierarchical single-core stability through policy-driven breakthrough innovation and supply-dominated institutional construction-though both ultimately require formal-informal system synergy.Their coevolution is driven by dynamic interactions of path dependence(weakening influence),learning-innovation(strengthening influence),and relationship selection(inverted U-shaped trajectory),with divergent development paths rooted in TAIC’s grassroots self-organization genes versus WAIC’s top-level design genes,amplified by core enterprises’strategic disparities.The research findings can not only provide decision-making support for China’s industrial upgrading,but also contribute China’s insights to global economic governance. 展开更多
关键词 endogenous automobile industrial clusters evolutionary characteristics driving mechanism Taizhou Wuhu China
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Equivalent Modeling with Passive Filter Parameter Clustering for Photovoltaic Power Stations Based on a Particle Swarm Optimization K-Means Algorithm
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作者 Binjiang Hu Yihua Zhu +3 位作者 Liang Tu Zun Ma Xian Meng Kewei Xu 《Energy Engineering》 2026年第1期431-459,共29页
This paper proposes an equivalent modeling method for photovoltaic(PV)power stations via a particle swarm optimization(PSO)K-means clustering(KMC)algorithm with passive filter parameter clustering to address the compl... This paper proposes an equivalent modeling method for photovoltaic(PV)power stations via a particle swarm optimization(PSO)K-means clustering(KMC)algorithm with passive filter parameter clustering to address the complexities,simulation time cost and convergence problems of detailed PV power station models.First,the amplitude–frequency curves of different filter parameters are analyzed.Based on the results,a grouping parameter set for characterizing the external filter characteristics is established.These parameters are further defined as clustering parameters.A single PV inverter model is then established as a prerequisite foundation.The proposed equivalent method combines the global search capability of PSO with the rapid convergence of KMC,effectively overcoming the tendency of KMC to become trapped in local optima.This approach enhances both clustering accuracy and numerical stability when determining equivalence for PV inverter units.Using the proposed clustering method,both a detailed PV power station model and an equivalent model are developed and compared.Simulation and hardwarein-loop(HIL)results based on the equivalent model verify that the equivalent method accurately represents the dynamic characteristics of PVpower stations and adapts well to different operating conditions.The proposed equivalent modeling method provides an effective analysis tool for future renewable energy integration research. 展开更多
关键词 Photovoltaic power station multi-machine equivalentmodeling particle swarmoptimization K-means clustering algorithm
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Single-atom collaboration with cluster for accelerated nitrate electroreduction:Synergy revelation via machine learning and DFT calculations
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作者 Ruochen Zhu Haoyu Wang +4 位作者 Kongke Tang Xinyuan Yang Xiuxian Zhao Jiayuan Yu Riming Hu 《Journal of Energy Chemistry》 2026年第1期842-851,I0019,共11页
Exploring high-performance electrocatalysts for the nitrate reduction reaction(NO_(3)RR)is crucial for environmental nitrate removal and ammonia synthesis.Single-atom collaboration with cluster can provide sufficient ... Exploring high-performance electrocatalysts for the nitrate reduction reaction(NO_(3)RR)is crucial for environmental nitrate removal and ammonia synthesis.Single-atom collaboration with cluster can provide sufficient active sites for catalysts to promote NO_(3)RR,yet the unclear synergistic effect between the two hinders their rational design.Herein,a series of Ir_(3)clusters and metal single atoms co-embedded in graphitic carbon nitride(g-CN)catalysts(Ir_(3)M1)were constructed,and the synergistic effects of Ir_(3)clusters and M1 single atoms on the NO_(3)RR catalytic mechanism and activity were systematically explored using density functional theory(DFT)calculations combined with machine learning.Comprehensive evaluations of structural stability and catalytic activity demonstrate that the synergy between single atoms and clusters effectively balances the adsorption energies of key intermediates,yielding exceptional catalytic performance(the limiting potential of Ir_(3)Ti_(1)can reach−0.22 V).Machine learning models further clarify the synergistic mechanism,where the geometric configurations of clusters serve as critical features for modulating the catalytic activity of single-atom sites,whereas the electronic structures of single atoms directly govern the reactivity of cluster sites.This DFT-machine learning approach provides theoretical guidelines for catalyst design and a predictive framework for efficient NO_(3)RR electrocatalysts. 展开更多
关键词 Nitrate reduction reaction Density functional theory Single-atom catalysts cluster Machine learning
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Growing Together——Villages in Zhejiang form clusters for common development
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作者 LIU TING 《ChinAfrica》 2026年第2期22-24,共3页
Villager Pan Chunlin is witnessing a boom in his homestay business.More and more visitors are coming to his village,Yucun Village in Anji County,Huzhou City,Zhejiang Province.
关键词 Huzhou city Zhejiang province VILLAGES VISITORS Yucun village clusterS common development homestay business
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The five major textile and apparel industry clusters in Xinjiang have achieved an output value exceeding 220 billion yuan
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作者 Qiu Shuchen 《China Textile》 2026年第1期34-35,共2页
In the Tianshan region,a complete textile industry chain has been established,covering the entire process from cotton cultivation and chemical fiber production,through spinning,weaving,dyeing,and finishing,and further... In the Tianshan region,a complete textile industry chain has been established,covering the entire process from cotton cultivation and chemical fiber production,through spinning,weaving,dyeing,and finishing,and further extending to apparel,home textiles,and industrial textiles.In November 2025,the first list of five characteristic textile and apparel industry clusters in Xinjiang was officially announced,marking a new stage in the clustering of Xinjiang's textile and apparel industry.Data shows that the total output value of Xinjiang's cotton and textile and apparel industry chain has exceeded 220 billion yuan.With the nation's largest cotton production,a complete industrial chain system,and strong synergistic effects,Xinjiang has become a leading and highly competitive textile industry hub in China. 展开更多
关键词 clustering XINJIANG cotton production apparel industry chemical fiber industrial chain textile industry output value
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A Novel Semi-Supervised Multi-View Picture Fuzzy Clustering Approach for Enhanced Satellite Image Segmentation
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作者 Pham Huy Thong Hoang Thi Canh +2 位作者 Nguyen Tuan Huy Nguyen Long Giang Luong Thi Hong Lan 《Computers, Materials & Continua》 2026年第3期1092-1117,共26页
Satellite image segmentation plays a crucial role in remote sensing,supporting applications such as environmental monitoring,land use analysis,and disaster management.However,traditional segmentation methods often rel... Satellite image segmentation plays a crucial role in remote sensing,supporting applications such as environmental monitoring,land use analysis,and disaster management.However,traditional segmentation methods often rely on large amounts of labeled data,which are costly and time-consuming to obtain,especially in largescale or dynamic environments.To address this challenge,we propose the Semi-Supervised Multi-View Picture Fuzzy Clustering(SS-MPFC)algorithm,which improves segmentation accuracy and robustness,particularly in complex and uncertain remote sensing scenarios.SS-MPFC unifies three paradigms:semi-supervised learning,multi-view clustering,and picture fuzzy set theory.This integration allows the model to effectively utilize a small number of labeled samples,fuse complementary information from multiple data views,and handle the ambiguity and uncertainty inherent in satellite imagery.We design a novel objective function that jointly incorporates picture fuzzy membership functions across multiple views of the data,and embeds pairwise semi-supervised constraints(must-link and cannot-link)directly into the clustering process to enhance segmentation accuracy.Experiments conducted on several benchmark satellite datasets demonstrate that SS-MPFC significantly outperforms existing state-of-the-art methods in segmentation accuracy,noise robustness,and semantic interpretability.On the Augsburg dataset,SS-MPFC achieves a Purity of 0.8158 and an Accuracy of 0.6860,highlighting its outstanding robustness and efficiency.These results demonstrate that SSMPFC offers a scalable and effective solution for real-world satellite-based monitoring systems,particularly in scenarios where rapid annotation is infeasible,such as wildfire tracking,agricultural monitoring,and dynamic urban mapping. 展开更多
关键词 Multi-view clustering satellite image segmentation semi-supervised learning picture fuzzy sets remote sensing
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A Quantum-Inspired Algorithm for Clustering and Intrusion Detection
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作者 Gang Xu Lefeng Wang +5 位作者 Yuwei Huang Yong Lu Xin Liu Weijie Tan Zongpeng Li Xiu-Bo Chen 《Computers, Materials & Continua》 2026年第4期1180-1215,共36页
The Intrusion Detection System(IDS)is a security mechanism developed to observe network traffic and recognize suspicious or malicious activities.Clustering algorithms are often incorporated into IDS;however,convention... The Intrusion Detection System(IDS)is a security mechanism developed to observe network traffic and recognize suspicious or malicious activities.Clustering algorithms are often incorporated into IDS;however,conventional clustering-based methods face notable drawbacks,including poor scalability in handling high-dimensional datasets and a strong dependence of outcomes on initial conditions.To overcome the performance limitations of existing methods,this study proposes a novel quantum-inspired clustering algorithm that relies on a similarity coefficient-based quantum genetic algorithm(SC-QGA)and an improved quantum artificial bee colony algorithm hybrid K-means(IQABC-K).First,the SC-QGA algorithmis constructed based on quantum computing and integrates similarity coefficient theory to strengthen genetic diversity and feature extraction capabilities.For the subsequent clustering phase,the process based on the IQABC-K algorithm is enhanced with the core improvement of adaptive rotation gate and movement exploitation strategies to balance the exploration capabilities of global search and the exploitation capabilities of local search.Simultaneously,the acceleration of convergence toward the global optimum and a reduction in computational complexity are facilitated by means of the global optimum bootstrap strategy and a linear population reduction strategy.Through experimental evaluation with multiple algorithms and diverse performance metrics,the proposed algorithm confirms reliable accuracy on three datasets:KDD CUP99,NSL_KDD,and UNSW_NB15,achieving accuracy of 98.57%,98.81%,and 98.32%,respectively.These results affirm its potential as an effective solution for practical clustering applications. 展开更多
关键词 Intrusion detection clusterING quantum artificial bee colony algorithm K-MEANS quantum genetic algorithm
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Social Network and Value Chain Integration:Unraveling the Formation and Evolution of Meizhou Pomelo Industry Cluster in China
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作者 YANG Ren LIN Yuancheng ZHANG Xin 《Chinese Geographical Science》 2026年第2期239-255,共17页
The shift toward specialized and large-scale agricultural production has spurred the emergence of agricultural clusters as key forces of rural vitalization and sustainable development.This paper explored the formation... The shift toward specialized and large-scale agricultural production has spurred the emergence of agricultural clusters as key forces of rural vitalization and sustainable development.This paper explored the formation and evolution of Meizhou pomelo industry cluster in China,focusing on its role in restructuring rural socio-economic systems and integrating the whole value chains.Based on a case study employing qualitative methods such as in-depth interviews and participatory observation,the agricultural cluster evolution of Meizhou pomelo was categorized into three key phases of initial decentralization,self-organized scaling,and reorganized clustering.Geographical proximity and industrial agglomeration constitute the physical foundation,while vertical/horizontal linkages,technologic-al innovation,and policy support enhance competitiveness.Special mechanisms emerge through localized social networks,farmer co-operatives’activation,and cross-regional market expansion.The cluster’s impact is manifested in the shift from extensive to standard-ized and modernized production,diversified and flexible livelihood of farmers,and the integration of agriculture with industry and ser-vices.The development of the whole value chain based on agricultural cluster represents a critical pathway for achieving agricultural modernization,encompassing both internal and external value chain optimization.Through quality assurance systems,product diversi-fication strategies,operational efficiency improvements,and brand enhancement,these clusters amplify product value propositions and market competitiveness.This systemic approach facilitates supply-demand coordination,enables resource synergies,and optimizes eco-nomic returns across the horizontal and vertical value chain.This paper argues that agricultural clusters serve as strategic catalysts for sustainable rural development by reconstructing local production systems,fostering innovation ecosystems,and aligning agricultural modernization.It contributes to debates on rural vitalization by demonstrating how agricultural clustering can reconfigure rural areas as hubs of ecological modernization,rather than mere urban peripheries. 展开更多
关键词 agricultural cluster sustainable rural development agricultural systems social network whole value chain China
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Selective heterometal doping in isostructural clusters converts phosphorescence to TADF with over 100-fold enhancing
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作者 Xu-Yang Ding Jin-Yun Wang +3 位作者 Lin-Xi Shi Zhi-Ping Kang Hao Zeng Zhong-Ning Chen 《Science China Chemistry》 2026年第2期716-722,共7页
Precise heterometal doping or substitution of specific metal sites in isostructural metal clusters remains a formidable synthetic challenge,despite its transformative potential for modulating excited-state characteris... Precise heterometal doping or substitution of specific metal sites in isostructural metal clusters remains a formidable synthetic challenge,despite its transformative potential for modulating excited-state characteristics and customizing optical properties.In this work,we achieved the precise synthesis of isostructural alloy clusters R/S-Ag_(3)Cu([Ag_(3)Cu(tppm)(R/S-IPTT)]ClO_(4),R/S-IPTT=R/S-4-isopropylthiazolidine-2-thiolate,tppm=tris(diphenylphosphino)methane)in high yield(89%-91%)through selective doping of a Cu(Ⅰ)atom into chiral homometallic cluster enantiomers R/S-Ag_(4)([Ag_(4)(tppm)(R/S-IPTT)]ClO_(4)).In stark contrast to R/S-Ag_(4)(Φ_(em)<0.5%)that displays weak circularly polarized luminescence(CPL)with phosphorescence characteristic,R/S-Ag_(3)Cu(Φ_(em)≈70%)demonstrates strong CPL properties featured with thermally activated delay fluorescence(TADF)at ambient temperature.The selective substitution of the apical Ag(Ⅰ)atom in Ag_(4)triangular pyramid with a Cu(Ⅰ)atom not only gives rise to beyond 100-fold boosting of photoluminescence quantum yield(PLQY),but also leads to more pronounced optically chiral activity of alloy clusters in excited states in view of the larger photoluminescence dissymmetry factors(g_(PL))of R/S-Ag_(3)Cu(-3.5×10^(-3)/3.4×10^(-3))than that of R/S-Ag_(4)(-2.7×10^(-3)/2.6×10^(-3)).Furthermore,compared with chiral homometallic clusters R/S-Cu_(4)([Cu_(4)(tppm)(R/S-IPTT)]ClO_(4))with the same TADF characteristic at ambient temperature,R/S-Ag_(3)Cu manifests 1.7-fold PLQY and 6-fold g_(PL)due to faster reverse intersystem crossing(RISC)and more effective coupling of electric and magnetic transition moments in alloy clusters.This work not only presents a typical example of selective heterometal doping to modulate excited-state properties of isostructural metal clusters,but also gets deeper insight into the doping chemistry of dissimilar metals at the molecular level. 展开更多
关键词 heterometal doping alloy cluster PHOTOLUMINESCENCE thermally activated delay fluorescence circularly polarized luminescence
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Multipoint Deformation Prediction Model Based on Clustering Partition of Extra High-Arch Dams
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作者 Bin Ou Haoquan Chi +3 位作者 Xu’an Qian Shuyan Fu Zhirui Miao Dingzhu Zhao 《Computer Modeling in Engineering & Sciences》 2026年第1期546-576,共31页
Deformation prediction for extra-high arch dams is highly important for ensuring their safe operation.To address the challenges of complex monitoring data,the uneven spatial distribution of deformation,and the constru... Deformation prediction for extra-high arch dams is highly important for ensuring their safe operation.To address the challenges of complex monitoring data,the uneven spatial distribution of deformation,and the construction and optimization of a prediction model for deformation prediction,a multipoint ultrahigh arch dam deformation prediction model,namely,the CEEMDAN-KPCA-GSWOA-KELM,which is based on a clustering partition,is pro-posed.First,the monitoring data are preprocessed via variational mode decomposition(VMD)and wavelet denoising(WT),which effectively filters out noise and improves the signal-to-noise ratio of the data,providing high-quality input data for subsequent prediction models.Second,scientific cluster partitioning is performed via the K-means++algorithm to precisely capture the spatial distribution characteristics of extra-high arch dams and ensure the consistency of deformation trends at measurement points within each partition.Finally,CEEMDAN is used to separate monitoring data,predict and analyze each component,combine the KPCA(Kernel Principal Component Analysis)and the KELM(Kernel Extreme Learning Machine)optimized by the GSWOA(Global Search Whale Optimization Algorithm),integrate the predictions of each component via reconstruction methods,and precisely predict the overall trend of ultrahigh arch dam deformation.An extra high arch dam project is taken as an example and validated via a comparative analysis of multiple models.The results show that the multipoint deformation prediction model in this paper can combine data from different measurement points,achieve a comprehensive,precise prediction of the deformation situation of extra high arch dams,and provide strong technical support for safe operation. 展开更多
关键词 Extra high arch dams deformation prediction data noise reduction spatial distribution clustering partition
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Collective Prosperity:Zhejiang’s Rural Cluster Development Model
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作者 LIU TING 《China Today》 2026年第2期51-53,共3页
By encouraging collaboration,attracting young entrepreneurs,and setting up village-invested enterprises,rural communities in Zhejiang Province are growing their income streams.“Over the past years,we have seen more a... By encouraging collaboration,attracting young entrepreneurs,and setting up village-invested enterprises,rural communities in Zhejiang Province are growing their income streams.“Over the past years,we have seen more and more tourists coming to our village,and their stay here has grown longer.Many even said they don’t want to leave,”Pan Chunlin,a resident of Yucun Village in Anji County of Huzhou City,east China’s Zhejiang Province,told China Today.Pan is the owner of the Chunlin Lodge,a bed&breakfast(B&B)which received more than 70,000 visitors last year,generating over RMB 4 million in revenue. 展开更多
关键词 rural cluster development collaboration village invested enterprises encouraging collaborationattracting young entrepreneurs income streams chunlin lodgea
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FedCCM:Communication-Efficient Federated Learning via Clustered Client Momentum in Non-IID Settings
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作者 Hang Wen Kai Zeng 《Computers, Materials & Continua》 2026年第3期1690-1707,共18页
Federated learning often experiences slow and unstable convergence due to edge-side data heterogeneity.This problem becomes more severe when edge participation rate is low,as the information collected from different e... Federated learning often experiences slow and unstable convergence due to edge-side data heterogeneity.This problem becomes more severe when edge participation rate is low,as the information collected from different edge devices varies significantly.As a result,communication overhead increases,which further slows down the convergence process.To address this challenge,we propose a simple yet effective federated learning framework that improves consistency among edge devices.The core idea is clusters the lookahead gradients collected from edge devices on the cloud server to obtain personalized momentum for steering local updates.In parallel,a global momentum is applied during model aggregation,enabling faster convergence while preserving personalization.This strategy enables efficient propagation of the estimated global update direction to all participating edge devices and maintains alignment in local training,without introducing extra memory or communication overhead.We conduct extensive experiments on benchmark datasets such as Cifar100 and Tiny-ImageNet.The results confirm the effectiveness of our framework.On CIFAR-100,our method reaches 55%accuracy with 37 fewer rounds and achieves a competitive final accuracy of 65.46%.Even under extreme non-IID scenarios,it delivers significant improvements in both accuracy and communication efficiency.The implementation is publicly available at https://github.com/sjmp525/CollaborativeComputing/tree/FedCCM(accessed on 20 October 2025). 展开更多
关键词 Federated learning distributed computation communication efficient momentum clustering non-independent and identically distributed(non-IID)
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