Purpose:The interdisciplinary nature and rapid development of the Semantic Web led to the mass publication of RDF data in a large number of widely accepted serialization formats,thus developing out the necessity for R...Purpose:The interdisciplinary nature and rapid development of the Semantic Web led to the mass publication of RDF data in a large number of widely accepted serialization formats,thus developing out the necessity for RDF data processing with specific purposes.The paper reports on an assessment of chief RDF data endpoint challenges and introduces the RDF Adaptor,a set of plugins for RDF data processing which covers the whole life-cycle with high efficiency.Design/methodology/approach:The RDFAdaptor is designed based on the prominent ETL tool—Pentaho Data Integration—which provides a user-friendly and intuitive interface and allows connect to various data sources and formats,and reuses the Java framework RDF4J as middleware that realizes access to data repositories,SPARQL endpoints and all leading RDF database solutions with SPARQL 1.1 support.It can support effortless services with various configuration templates in multi-scenario applications,and help extend data process tasks in other services or tools to complement missing functions.Findings:The proposed comprehensive RDF ETL solution—RDFAdaptor—provides an easy-to-use and intuitive interface,supports data integration and federation over multi-source heterogeneous repositories or endpoints,as well as manage linked data in hybrid storage mode.Research limitations:The plugin set can support several application scenarios of RDF data process,but error detection/check and interaction with other graph repositories remain to be improved.Practical implications:The plugin set can provide user interface and configuration templates which enable its usability in various applications of RDF data generation,multi-format data conversion,remote RDF data migration,and RDF graph update in semantic query process.Originality/value:This is the first attempt to develop components instead of systems that can include extract,consolidate,and store RDF data on the basis of an ecologically mature data warehousing environment.展开更多
Purpose:Centralized on the construction of a personalized knowledge environment that can better meet the need of Chinese agricultural researchers,this paper presents the practice conducted by the National Agricultural...Purpose:Centralized on the construction of a personalized knowledge environment that can better meet the need of Chinese agricultural researchers,this paper presents the practice conducted by the National Agricultural Library(NAL)of Chinese Academy of Agricultural Sciences(CAAS)in the digital research environment.Based on the analysis of information needs of Chinese agricultural researchers,CAAS constructed digital research environments for its researchers at different levels,by means of providing more professional knowledge services for targeted researcher users.Design/methodology/approach:On the basis of the construction of public service platform—National Agriculture Information System of the Library of CAAS(i.e.NAL),local resources were integrated with public open resources by using key technologies,such as Web 2.0,knowledge navigation,linked data and intelligent retrieval,to construct an institutional personalized digital repository for CAAS researchers.Findings:By using the construction tool CAASPKE,knowledge environment platforms have been constructed for 10 CAAS institutes,taking roughly 33%of CAAS institutes.In addition,16 discipline information environment platforms have been set up for CAAS research teams,and 5 professional digital libraries for provincial agricultural academies,which spread in Beijing,Shanxi,Sichuan,and the Xinjiang and Tibet Autonomous Regions.Research limitations:User’s local collections ought to be integrated with IR resources of the CAAS platform constantly.Due to the lack of overall knowledge resources,functions of the platform have not been fully explored,so the effect need be evaluated with the time being.Practical implications:The construction of research knowledge environment in CAAS has not only contributed to the development of its personalized knowledge service system,but also made the functions of libraries transformed into the information service system.In this case,CAAS libraries are now playing more and more important roles in the innovation process of Chinese agricultural researchers.Originality/value:The innovative practice is the first endeavor that ever implemented in the agricultural information service area across China's Mainland.The construction tool developed for the knowledge environment of personalization could customize resources flexibly according to the need of different CAAS users,and it can organize the knowledge resources of CAAS institutes effectively.展开更多
Purpose: The study was carried out to construct a domain knowledge service system based on the Scientific & Technological Knowledge Organization Systems(STKOS). Design/methodology/approach: The framework of a doma...Purpose: The study was carried out to construct a domain knowledge service system based on the Scientific & Technological Knowledge Organization Systems(STKOS). Design/methodology/approach: The framework of a domain knowledge service system is designed on the basis of the STKOS, and the STKOS science and technology vocabularies, category systems, and ontology networks are applied to realize the knowledge organization and semantic linking of the scientific and technological information resources. Meanwhile, related knowledge-mining analysis algorithms and models are improved, and some tools such as Solr and D3 are used for developing the system. This system integrates various knowledge service modules, including unified search of domain information resources and knowledge-linked navigation, domain hotspot and burst topics monitoring analysis, knowledge structure and evolution analysis, literature citation network, and research agents' cooperative relationship network analysis. Findings: The system can help to refine descriptions, knowledge organization, and the semantic linking of various kinds of information resources closely related to science and technology. Such resources include domain literature, institutions, scientists, projects, and more. Research limitations: Trial assessment and performance improvement should be carried out for the knowledge service application on the basis of more types of and larger quantities of domain information resources.Practical implications: The domain knowledge service system provides an integrated knowledge discovery tool, as well as several kinds of knowledge mining analysis services for researchers.Originality/value: Our practice can be used as a valuable guide for libraries and information institutions that plan to provide deep domain knowledge services.展开更多
To study the effect of nano‐silica particles on the conductivity characteristics of ethylene propylene diene monomer(EPDM)insulation,EPDM nanocomposites with different mass fractions of nano silica were prepared via ...To study the effect of nano‐silica particles on the conductivity characteristics of ethylene propylene diene monomer(EPDM)insulation,EPDM nanocomposites with different mass fractions of nano silica were prepared via the melt‐blending method.Scanning electron microscopy was used to analyze the dispersion of nanoparticles in EPDM.Based on the Fourier‐transform infrared spectrum,the bonding properties between the nanoparticles and EPDM were analyzed.The steady‐state current at 30-100°C and 1-20 kV/mm was measured.Moreover,the conductivity characteristic was analyzed.The experimental results show that as the content of nano‐silica increases,the electrical conductivity of EPDM nanocomposite as well as the threshold field strength gradually decreases.Samples with a small number of nanoparticles will increase the activation energy of the carrier conductivity,and the interface region effect introduced by nanoparticles will reduce the carrier mobility and concentration,resulting in a lower conductivity.Comparing the calculated value of the dielectric constant with the measured value can conclude that the high‐field conductance process is a combination of the electrode effect and the body effect,which in this case,Schottky effect dominates.展开更多
基金This work is supported by“National Social Science Foundation in China”Project(19BTQ061)“Integration and Development on A Next Generation of Open Knowledge Services System and Key Technologies”project(2020XM05).
文摘Purpose:The interdisciplinary nature and rapid development of the Semantic Web led to the mass publication of RDF data in a large number of widely accepted serialization formats,thus developing out the necessity for RDF data processing with specific purposes.The paper reports on an assessment of chief RDF data endpoint challenges and introduces the RDF Adaptor,a set of plugins for RDF data processing which covers the whole life-cycle with high efficiency.Design/methodology/approach:The RDFAdaptor is designed based on the prominent ETL tool—Pentaho Data Integration—which provides a user-friendly and intuitive interface and allows connect to various data sources and formats,and reuses the Java framework RDF4J as middleware that realizes access to data repositories,SPARQL endpoints and all leading RDF database solutions with SPARQL 1.1 support.It can support effortless services with various configuration templates in multi-scenario applications,and help extend data process tasks in other services or tools to complement missing functions.Findings:The proposed comprehensive RDF ETL solution—RDFAdaptor—provides an easy-to-use and intuitive interface,supports data integration and federation over multi-source heterogeneous repositories or endpoints,as well as manage linked data in hybrid storage mode.Research limitations:The plugin set can support several application scenarios of RDF data process,but error detection/check and interaction with other graph repositories remain to be improved.Practical implications:The plugin set can provide user interface and configuration templates which enable its usability in various applications of RDF data generation,multi-format data conversion,remote RDF data migration,and RDF graph update in semantic query process.Originality/value:This is the first attempt to develop components instead of systems that can include extract,consolidate,and store RDF data on the basis of an ecologically mature data warehousing environment.
基金supported by the National Science & Technology Pillar Program During the Twelfth Five-year Period Plan of China(Grant No.2011BAH10B06)
文摘Purpose:Centralized on the construction of a personalized knowledge environment that can better meet the need of Chinese agricultural researchers,this paper presents the practice conducted by the National Agricultural Library(NAL)of Chinese Academy of Agricultural Sciences(CAAS)in the digital research environment.Based on the analysis of information needs of Chinese agricultural researchers,CAAS constructed digital research environments for its researchers at different levels,by means of providing more professional knowledge services for targeted researcher users.Design/methodology/approach:On the basis of the construction of public service platform—National Agriculture Information System of the Library of CAAS(i.e.NAL),local resources were integrated with public open resources by using key technologies,such as Web 2.0,knowledge navigation,linked data and intelligent retrieval,to construct an institutional personalized digital repository for CAAS researchers.Findings:By using the construction tool CAASPKE,knowledge environment platforms have been constructed for 10 CAAS institutes,taking roughly 33%of CAAS institutes.In addition,16 discipline information environment platforms have been set up for CAAS research teams,and 5 professional digital libraries for provincial agricultural academies,which spread in Beijing,Shanxi,Sichuan,and the Xinjiang and Tibet Autonomous Regions.Research limitations:User’s local collections ought to be integrated with IR resources of the CAAS platform constantly.Due to the lack of overall knowledge resources,functions of the platform have not been fully explored,so the effect need be evaluated with the time being.Practical implications:The construction of research knowledge environment in CAAS has not only contributed to the development of its personalized knowledge service system,but also made the functions of libraries transformed into the information service system.In this case,CAAS libraries are now playing more and more important roles in the innovation process of Chinese agricultural researchers.Originality/value:The innovative practice is the first endeavor that ever implemented in the agricultural information service area across China's Mainland.The construction tool developed for the knowledge environment of personalization could customize resources flexibly according to the need of different CAAS users,and it can organize the knowledge resources of CAAS institutes effectively.
基金supported by the Ministry of Science and Technology of China(Project No.:2011BAH10B06)
文摘Purpose: The study was carried out to construct a domain knowledge service system based on the Scientific & Technological Knowledge Organization Systems(STKOS). Design/methodology/approach: The framework of a domain knowledge service system is designed on the basis of the STKOS, and the STKOS science and technology vocabularies, category systems, and ontology networks are applied to realize the knowledge organization and semantic linking of the scientific and technological information resources. Meanwhile, related knowledge-mining analysis algorithms and models are improved, and some tools such as Solr and D3 are used for developing the system. This system integrates various knowledge service modules, including unified search of domain information resources and knowledge-linked navigation, domain hotspot and burst topics monitoring analysis, knowledge structure and evolution analysis, literature citation network, and research agents' cooperative relationship network analysis. Findings: The system can help to refine descriptions, knowledge organization, and the semantic linking of various kinds of information resources closely related to science and technology. Such resources include domain literature, institutions, scientists, projects, and more. Research limitations: Trial assessment and performance improvement should be carried out for the knowledge service application on the basis of more types of and larger quantities of domain information resources.Practical implications: The domain knowledge service system provides an integrated knowledge discovery tool, as well as several kinds of knowledge mining analysis services for researchers.Originality/value: Our practice can be used as a valuable guide for libraries and information institutions that plan to provide deep domain knowledge services.
基金National Natural Science Foundation of China,Grant/Award Number:51977137。
文摘To study the effect of nano‐silica particles on the conductivity characteristics of ethylene propylene diene monomer(EPDM)insulation,EPDM nanocomposites with different mass fractions of nano silica were prepared via the melt‐blending method.Scanning electron microscopy was used to analyze the dispersion of nanoparticles in EPDM.Based on the Fourier‐transform infrared spectrum,the bonding properties between the nanoparticles and EPDM were analyzed.The steady‐state current at 30-100°C and 1-20 kV/mm was measured.Moreover,the conductivity characteristic was analyzed.The experimental results show that as the content of nano‐silica increases,the electrical conductivity of EPDM nanocomposite as well as the threshold field strength gradually decreases.Samples with a small number of nanoparticles will increase the activation energy of the carrier conductivity,and the interface region effect introduced by nanoparticles will reduce the carrier mobility and concentration,resulting in a lower conductivity.Comparing the calculated value of the dielectric constant with the measured value can conclude that the high‐field conductance process is a combination of the electrode effect and the body effect,which in this case,Schottky effect dominates.
