As one of the core modules for air traffic flow management,Air Traffic Flow Prediction(ATFP)in the Multi-Airport System(MAS)is a prerequisite for demand and capacity balance in the complex meteorological environment.D...As one of the core modules for air traffic flow management,Air Traffic Flow Prediction(ATFP)in the Multi-Airport System(MAS)is a prerequisite for demand and capacity balance in the complex meteorological environment.Due to the challenge of implicit interaction mechanism among traffic flow,airspace capacity and weather impact,the Weather-aware ATFP(Wa-ATFP)is still a nontrivial issue.In this paper,a novel Multi-faceted Spatio-Temporal Graph Convolutional Network(MSTGCN)is proposed to address the Wa-ATFP within the complex operations of MAS.Firstly,a spatio-temporal graph is constructed with three different nodes,including airport,route,and fix to describe the topology structure of MAS.Secondly,a weather-aware multi-faceted fusion module is proposed to integrate the feature of air traffic flow and the auxiliary features of capacity and weather,which can effectively address the complex impact of severe weather,e.g.,thunderstorms.Thirdly,to capture the latent connections of nodes,an adaptive graph connection constructor is designed.The experimental results with the real-world operational dataset in Guangdong-Hong Kong-Macao Greater Bay Area,China,validate that the proposed approach outperforms the state-of-the-art machine-learning and deep-learning based baseline approaches in performance.展开更多
Purpose:This paper informs about the publication of the second edition of the Integrative Levels Classification(ILC2),a freely-faceted knowledge organization system(KOS),and reviews the main changes that have been int...Purpose:This paper informs about the publication of the second edition of the Integrative Levels Classification(ILC2),a freely-faceted knowledge organization system(KOS),and reviews the main changes that have been introduced as compared to its first edition(ILC1).Design/methodology/approach:The most relevant changes are illustrated,with special reference to those of interest to general classification theory,by means of examples of notation for individual classes and combinations of them.Findings:Changes introduced in ILC2 include:the names and order of some main classes;the development of subclasses for various phenomena,especially quantities and algebraic structures;the order of facet categories and the new category of Disorder;notation for special facets;distinction of the semantical function of facets(attributes)from their syntactic function.The system can be freely accessed online through a PHP browser as well as in SKOS format.Research limitations:Only a selection of changed classes is discussed for space reasons.Practical implications:ILC1 has been previously applied to the BARTOC directory of KOSs.Update of BARTOC data to ILC2 and application of ILC2 to further information systems are envisaged.Possible methods for reclassifying BARTOC with ILC2 are discussed.Originality:ILC is a newly developed classification system,based on phenomena instead of traditional disciplines and featuring various innovative devices.This paper is an original account of its most recent evolution.展开更多
Naturally occurring hematite has been widely studied in the Fenton-like system for water pollutant remediation due to its abundance and non-toxicity.However,its inadequate catalytic activity results in difficulty in e...Naturally occurring hematite has been widely studied in the Fenton-like system for water pollutant remediation due to its abundance and non-toxicity.However,its inadequate catalytic activity results in difficulty in effectively degrading pollutants in the catalytic degradation system that it constitutes.Thus,we constructed a photochemical system composed of hematite with{001}facet of high activity facet and low-cost and non-toxic oxalic acid(OA)for the removal of various types of pollutants.The removal rate for the degradation of metronidazole,tetracycline hydrochloride,Rhodamine B,and hexavalent chromium by hematite nanoplate with the exposed{001}facet activating OA under visible light irradiation was 4.75,2.25,2.33,and 2.74 times than that by the exposed{110}facet,respectively.Density functional theory(DFT)calculation proved that the OA molecule was more easily adsorbed on the{001}facet of hematite than that on the{110}facet,which would favor the formation of the more Fe(Ⅲ)-OA complex and reactive species.In addition,the reactive site of metronidazole for the attraction of radicals was identified on the basis of the DFT calculation on the molecular occupied orbitals,and the possible degradation pathway for metronidazole included carbon chain fracture,hydroxyethyl-cleavage,denitrogenation,and hydroxylation.Thus,this finding may offer a valuable direction in designing an efficient iron-based catalyst based on facet engineering for the improved activity of Fenton-like systems such as OA activation.展开更多
The discrete element method(DEM)is used to analyze complex practical granular systems;however,the representation of real shapes is an important consideration because behavior of non-spherical particles is unlike that ...The discrete element method(DEM)is used to analyze complex practical granular systems;however,the representation of real shapes is an important consideration because behavior of non-spherical particles is unlike that of spherical particles both individually and collectively.In this study,we use non-uniform rational basis-splines(NURBS)to describe the shapes of non-spherical particles and introduce a contact detection scheme based on quadratic convergence,to simulate the behaviors of elliptical particles.The simulation results are compared with those based on polygons,in terms of the shape description and contact treatment,to demonstrate the high accuracy and efficiency of NURBS-based DEM.展开更多
基金supported by the National Key Research and Development Program of China(No.2022YFB2602402)the National Natural Science Foundation of China(Nos.U2033215 and U2133210).
文摘As one of the core modules for air traffic flow management,Air Traffic Flow Prediction(ATFP)in the Multi-Airport System(MAS)is a prerequisite for demand and capacity balance in the complex meteorological environment.Due to the challenge of implicit interaction mechanism among traffic flow,airspace capacity and weather impact,the Weather-aware ATFP(Wa-ATFP)is still a nontrivial issue.In this paper,a novel Multi-faceted Spatio-Temporal Graph Convolutional Network(MSTGCN)is proposed to address the Wa-ATFP within the complex operations of MAS.Firstly,a spatio-temporal graph is constructed with three different nodes,including airport,route,and fix to describe the topology structure of MAS.Secondly,a weather-aware multi-faceted fusion module is proposed to integrate the feature of air traffic flow and the auxiliary features of capacity and weather,which can effectively address the complex impact of severe weather,e.g.,thunderstorms.Thirdly,to capture the latent connections of nodes,an adaptive graph connection constructor is designed.The experimental results with the real-world operational dataset in Guangdong-Hong Kong-Macao Greater Bay Area,China,validate that the proposed approach outperforms the state-of-the-art machine-learning and deep-learning based baseline approaches in performance.
文摘Purpose:This paper informs about the publication of the second edition of the Integrative Levels Classification(ILC2),a freely-faceted knowledge organization system(KOS),and reviews the main changes that have been introduced as compared to its first edition(ILC1).Design/methodology/approach:The most relevant changes are illustrated,with special reference to those of interest to general classification theory,by means of examples of notation for individual classes and combinations of them.Findings:Changes introduced in ILC2 include:the names and order of some main classes;the development of subclasses for various phenomena,especially quantities and algebraic structures;the order of facet categories and the new category of Disorder;notation for special facets;distinction of the semantical function of facets(attributes)from their syntactic function.The system can be freely accessed online through a PHP browser as well as in SKOS format.Research limitations:Only a selection of changed classes is discussed for space reasons.Practical implications:ILC1 has been previously applied to the BARTOC directory of KOSs.Update of BARTOC data to ILC2 and application of ILC2 to further information systems are envisaged.Possible methods for reclassifying BARTOC with ILC2 are discussed.Originality:ILC is a newly developed classification system,based on phenomena instead of traditional disciplines and featuring various innovative devices.This paper is an original account of its most recent evolution.
基金supported by the National Natural Science Foundation of China(No.22176151)。
文摘Naturally occurring hematite has been widely studied in the Fenton-like system for water pollutant remediation due to its abundance and non-toxicity.However,its inadequate catalytic activity results in difficulty in effectively degrading pollutants in the catalytic degradation system that it constitutes.Thus,we constructed a photochemical system composed of hematite with{001}facet of high activity facet and low-cost and non-toxic oxalic acid(OA)for the removal of various types of pollutants.The removal rate for the degradation of metronidazole,tetracycline hydrochloride,Rhodamine B,and hexavalent chromium by hematite nanoplate with the exposed{001}facet activating OA under visible light irradiation was 4.75,2.25,2.33,and 2.74 times than that by the exposed{110}facet,respectively.Density functional theory(DFT)calculation proved that the OA molecule was more easily adsorbed on the{001}facet of hematite than that on the{110}facet,which would favor the formation of the more Fe(Ⅲ)-OA complex and reactive species.In addition,the reactive site of metronidazole for the attraction of radicals was identified on the basis of the DFT calculation on the molecular occupied orbitals,and the possible degradation pathway for metronidazole included carbon chain fracture,hydroxyethyl-cleavage,denitrogenation,and hydroxylation.Thus,this finding may offer a valuable direction in designing an efficient iron-based catalyst based on facet engineering for the improved activity of Fenton-like systems such as OA activation.
基金This work is financially supported by TOTAL S.A.and the authors ofChinese Academy of Sciences also acknowledge the Science Chal-lenge Project(Grand No.TZ2016001)the National Natural Science Foundation of China(Grand Nos.21821005 and 91834303)the Key Research Program of Frontier Science of the Chinese Academy of Sciences(Grant No.QYZDJ-SSW-JSC029).
文摘The discrete element method(DEM)is used to analyze complex practical granular systems;however,the representation of real shapes is an important consideration because behavior of non-spherical particles is unlike that of spherical particles both individually and collectively.In this study,we use non-uniform rational basis-splines(NURBS)to describe the shapes of non-spherical particles and introduce a contact detection scheme based on quadratic convergence,to simulate the behaviors of elliptical particles.The simulation results are compared with those based on polygons,in terms of the shape description and contact treatment,to demonstrate the high accuracy and efficiency of NURBS-based DEM.
