Point-based surface has been widely used in computer graphics for modeling, animation, visualization, simulation of liq- uid and so on. Furthermore, particle-based approach can distribute the surface sampling points a...Point-based surface has been widely used in computer graphics for modeling, animation, visualization, simulation of liq- uid and so on. Furthermore, particle-based approach can distribute the surface sampling points and control its parameters according to the needs of the application. In this paper, we examine several kinds of algorithms presented over the last decades, with the main focus on particle sampling technologies for implicit surface. Therefore, we classify various algorithms into categories, describe main ideas behind each categories, and compare the advantages and shortcomings of the algorithms in each category.展开更多
Detection and tracking of multi-target with unknown and varying number is a challenging issue, especially under the condition of low signal-to-noise ratio(SNR). A modified multi-target track-before-detect(TBD) method ...Detection and tracking of multi-target with unknown and varying number is a challenging issue, especially under the condition of low signal-to-noise ratio(SNR). A modified multi-target track-before-detect(TBD) method was proposed to tackle this issue using a nonstandard point observation model. The method was developed from sequential Monte Carlo(SMC)-based probability hypothesis density(PHD) filter, and it was implemented by modifying the original calculation in update weights of the particles and by adopting an adaptive particle sampling strategy. To efficiently execute the SMC-PHD based TBD method, a fast implementation approach was also presented by partitioning the particles into multiple subsets according to their position coordinates in 2D resolution cells of the sensor. Simulation results show the effectiveness of the proposed method for time-varying multi-target tracking using raw observation data.展开更多
Scanning Electron Microscopes(SEMs)are widely used in experimental science laboratories,often requiring cumbersome and repetitive user analysis.Automating SEM image analysis processes is highly desirable to address th...Scanning Electron Microscopes(SEMs)are widely used in experimental science laboratories,often requiring cumbersome and repetitive user analysis.Automating SEM image analysis processes is highly desirable to address this challenge.In particle sample analysis,Machine Learning(ML)has emerged as the most effective approach for particle segmentation.However,the time-intensive process of manually annotating thousands of SEM images limits the applicability of supervised learning approaches.Self-Supervised Learning(SSL)offers a promising alternative by enabling knowledge extraction from raw,unlabeled data.This study presents a framework for evaluating SSL techniques in SEM image analysis,focusing on novel methods leveraging the ConvNeXtV2 architecture for particle detection.A dataset comprising 25,000 SEM images is curated to benchmark these proposed SSL methods.The results demonstrate that ConvNeXtV2 models,with varying parameter counts,consistently outperform other techniques in particle detection across different length scales,achieving up to a34%reduction in relative error compared to established SSL methods.Furthermore,an ablation study explores the relationship between dataset size and SSL performance,providing actionable insights for practitioners regarding model selection and resource efficiency.This research advances the integration of SSL into autonomous analysis pipelines and supports its application in accelerating materials science discovery.展开更多
基金supported by the National Nature Science Foundation of China (61020106001,60903109,61103150)National Research Foundation for the Doctoral Program of Higher Education of China (20110131130004)
文摘Point-based surface has been widely used in computer graphics for modeling, animation, visualization, simulation of liq- uid and so on. Furthermore, particle-based approach can distribute the surface sampling points and control its parameters according to the needs of the application. In this paper, we examine several kinds of algorithms presented over the last decades, with the main focus on particle sampling technologies for implicit surface. Therefore, we classify various algorithms into categories, describe main ideas behind each categories, and compare the advantages and shortcomings of the algorithms in each category.
基金Projects(61002022,61471370)supported by the National Natural Science Foundation of China
文摘Detection and tracking of multi-target with unknown and varying number is a challenging issue, especially under the condition of low signal-to-noise ratio(SNR). A modified multi-target track-before-detect(TBD) method was proposed to tackle this issue using a nonstandard point observation model. The method was developed from sequential Monte Carlo(SMC)-based probability hypothesis density(PHD) filter, and it was implemented by modifying the original calculation in update weights of the particles and by adopting an adaptive particle sampling strategy. To efficiently execute the SMC-PHD based TBD method, a fast implementation approach was also presented by partitioning the particles into multiple subsets according to their position coordinates in 2D resolution cells of the sensor. Simulation results show the effectiveness of the proposed method for time-varying multi-target tracking using raw observation data.
基金funded by the German Research Foundation(DFG)under Project ID 390874152(POLiS Cluster of Excellence)N.J.S.,A.G.,G.C.,O.D.,A.J.were supported by the D2S2 program within the U.S.Department of Energy,Office of Basic Energy Sciences,Materials Sciences and Engineering Division under Contract No.DE-AC02-05-CH11231(D2S2 program,KCD2S2)A.G.acknowledges support from the Swiss National Science Foundation(SNSF,project#P500PN_222166).
文摘Scanning Electron Microscopes(SEMs)are widely used in experimental science laboratories,often requiring cumbersome and repetitive user analysis.Automating SEM image analysis processes is highly desirable to address this challenge.In particle sample analysis,Machine Learning(ML)has emerged as the most effective approach for particle segmentation.However,the time-intensive process of manually annotating thousands of SEM images limits the applicability of supervised learning approaches.Self-Supervised Learning(SSL)offers a promising alternative by enabling knowledge extraction from raw,unlabeled data.This study presents a framework for evaluating SSL techniques in SEM image analysis,focusing on novel methods leveraging the ConvNeXtV2 architecture for particle detection.A dataset comprising 25,000 SEM images is curated to benchmark these proposed SSL methods.The results demonstrate that ConvNeXtV2 models,with varying parameter counts,consistently outperform other techniques in particle detection across different length scales,achieving up to a34%reduction in relative error compared to established SSL methods.Furthermore,an ablation study explores the relationship between dataset size and SSL performance,providing actionable insights for practitioners regarding model selection and resource efficiency.This research advances the integration of SSL into autonomous analysis pipelines and supports its application in accelerating materials science discovery.