Standard examination is an effective approach to promote the teaching quality of modern education. On terms of the analysis of main target, function and constitution of special course examination system for remote edu...Standard examination is an effective approach to promote the teaching quality of modern education. On terms of the analysis of main target, function and constitution of special course examination system for remote education, the internet scheme of the examination system is given according to the students and teachers' requirements. The implementation method for the communication and dynamic production of tests on home page of the exam system are elaborated by using programming technology of Active Server Pages (ASP)3.0. The query of exam information and automatic marking of test questions can be easily realized by the developed exam system under World Wide Web enviromment according to users' requirements.展开更多
The accelerator-driven subcritical system (ADS) with a hard neutron energy spectrum was used to study transmutation of minor actinides (MAs). The aim of the study was to improve the efficiency of MA transmutation whil...The accelerator-driven subcritical system (ADS) with a hard neutron energy spectrum was used to study transmutation of minor actinides (MAs). The aim of the study was to improve the efficiency of MA transmutation while ensuring that variations in the effective multiplication factor (keff) remained within safe margins during reactor operation. All calculations were completed using code COUPLE3.0. The subcritical reactor was operated at a thermal power level of 800 MW, and a mixture of mononitrides of MAs and plutonium (Pu) was used as fuel. Zirconium nitride (ZrN) was used as an inert matrix in the fuel elements. The initial mass composition in terms of weight percentages in the heavy metal component (IHM) was 30.6% Pu/IHM and 69.4% MA/IHM. To verify the feasibility of this MA loading scheme, variations in keff, the amplification factor of the core, maximum power density and the content of MAs and Pu were calculated over six refueling cycles. Each cycle was of 600 days duration, and therefore, there were 3600 effective full power days. Results demonstrated that the effective transmutation support ratio of MAs was approximately 28, and the ADS was able to efficiently transmute MAs. The changes in other physical parameters were also within their normal ranges.It is concluded that the proposed MA transmutation scheme for an ADS core is reasonable.展开更多
Every day,the media reports tons of crimes that are considered by a large number of users and accumulate on a regular basis.Crime news exists on the Internet in unstructured formats such as books,websites,documents,an...Every day,the media reports tons of crimes that are considered by a large number of users and accumulate on a regular basis.Crime news exists on the Internet in unstructured formats such as books,websites,documents,and journals.From such homogeneous data,it is very challenging to extract relevant information which is a time-consuming and critical task for the public and law enforcement agencies.Keyword-based Information Retrieval(IR)systems rely on statistics to retrieve results,making it difficult to obtain relevant results.They are unable to understandthe user’s query and thus facewordmismatchesdue to context changes andthe inevitable semanticsof a given word.Therefore,such datasets need to be organized in a structured configuration,with the goal of efficiently manipulating the data while respecting the semantics of the data.An ontological semantic IR systemis needed that can find the right investigative information and find important clues to solve criminal cases.The semantic system retrieves information in view of the similarity of the semantics among indexed data and user queries.In this paper,we develop anontology-based semantic IRsystemthat leverages the latest semantic technologies including resource description framework(RDF),semantic protocol and RDF query language(SPARQL),semantic web rule language(SWRL),and web ontology language(OWL).We have conducted two experiments.In the first experiment,we implemented a keyword-based textual IR systemusing Apache Lucene.In the second experiment,we implemented a semantic systemthat uses ontology to store the data and retrieve precise results with high accuracy using SPARQL queries.The keyword-based system has filtered results with 51%accuracy,while the semantic system has filtered results with 95%accuracy,leading to significant improvements in the field and opening up new horizons for researchers.展开更多
在小单位,本来已经杂事缠身的你现在又要关注公司的Web网点的建立。怎么办?请考Adobe Systems PageMill3.0。虽然功能不能与Microsoft FrontPage98相匹敌,但PageMill售价比后者低50美元,而且其功能显然也不能等闲视之。PogeMill提供了...在小单位,本来已经杂事缠身的你现在又要关注公司的Web网点的建立。怎么办?请考Adobe Systems PageMill3.0。虽然功能不能与Microsoft FrontPage98相匹敌,但PageMill售价比后者低50美元,而且其功能显然也不能等闲视之。PogeMill提供了你需要的稳健易用的工具所具备的重要特性,如果你只是偶尔创建和管理小单位的网点,则该产品是一种不错的选择。展开更多
Web 3.0数字经济体系以区块链平台为基础设施,围绕加密货币、NFT、数字藏品等数字资产和去中心化金融(DeFi)、游戏金融(GameFi)等去中心化应用(DApp)开展各项社会经济活动.在公有链和开放联盟链下,作为DApp内核的智能合约可以由任何个...Web 3.0数字经济体系以区块链平台为基础设施,围绕加密货币、NFT、数字藏品等数字资产和去中心化金融(DeFi)、游戏金融(GameFi)等去中心化应用(DApp)开展各项社会经济活动.在公有链和开放联盟链下,作为DApp内核的智能合约可以由任何个人或组织予以部署,并对全体用户可见及可调用.这种开放性给经济发展带来了新的机遇,同时也蕴含了许多金融风险.以智能合约为中心分析了Web 3.0数字经济潜在的风险,并从智能合约的编码、功能、应用3个层面总结了风险感知技术的研究现状.首先介绍了智能合约漏洞检测技术的研究挑战、安全漏洞类型和4类漏洞检测方法;其次分析了常见的智能合约骗局类型,并根据训练数据的不同分类总结了现有的智能合约骗局识别技术;接着介绍了基于区块链交易记录对4种非法交易行为进行检测的技术现状;最后结合对现有工作局限性的分析,展望了未来的研究方向.展开更多
基金Sponsored by China Postdoctoral Science Foundation (No:200031)
文摘Standard examination is an effective approach to promote the teaching quality of modern education. On terms of the analysis of main target, function and constitution of special course examination system for remote education, the internet scheme of the examination system is given according to the students and teachers' requirements. The implementation method for the communication and dynamic production of tests on home page of the exam system are elaborated by using programming technology of Active Server Pages (ASP)3.0. The query of exam information and automatic marking of test questions can be easily realized by the developed exam system under World Wide Web enviromment according to users' requirements.
基金supported by the Strategic Priority Research Program of The Chinese Academy of Sciences(No.XDA21010202)
文摘The accelerator-driven subcritical system (ADS) with a hard neutron energy spectrum was used to study transmutation of minor actinides (MAs). The aim of the study was to improve the efficiency of MA transmutation while ensuring that variations in the effective multiplication factor (keff) remained within safe margins during reactor operation. All calculations were completed using code COUPLE3.0. The subcritical reactor was operated at a thermal power level of 800 MW, and a mixture of mononitrides of MAs and plutonium (Pu) was used as fuel. Zirconium nitride (ZrN) was used as an inert matrix in the fuel elements. The initial mass composition in terms of weight percentages in the heavy metal component (IHM) was 30.6% Pu/IHM and 69.4% MA/IHM. To verify the feasibility of this MA loading scheme, variations in keff, the amplification factor of the core, maximum power density and the content of MAs and Pu were calculated over six refueling cycles. Each cycle was of 600 days duration, and therefore, there were 3600 effective full power days. Results demonstrated that the effective transmutation support ratio of MAs was approximately 28, and the ADS was able to efficiently transmute MAs. The changes in other physical parameters were also within their normal ranges.It is concluded that the proposed MA transmutation scheme for an ADS core is reasonable.
文摘Every day,the media reports tons of crimes that are considered by a large number of users and accumulate on a regular basis.Crime news exists on the Internet in unstructured formats such as books,websites,documents,and journals.From such homogeneous data,it is very challenging to extract relevant information which is a time-consuming and critical task for the public and law enforcement agencies.Keyword-based Information Retrieval(IR)systems rely on statistics to retrieve results,making it difficult to obtain relevant results.They are unable to understandthe user’s query and thus facewordmismatchesdue to context changes andthe inevitable semanticsof a given word.Therefore,such datasets need to be organized in a structured configuration,with the goal of efficiently manipulating the data while respecting the semantics of the data.An ontological semantic IR systemis needed that can find the right investigative information and find important clues to solve criminal cases.The semantic system retrieves information in view of the similarity of the semantics among indexed data and user queries.In this paper,we develop anontology-based semantic IRsystemthat leverages the latest semantic technologies including resource description framework(RDF),semantic protocol and RDF query language(SPARQL),semantic web rule language(SWRL),and web ontology language(OWL).We have conducted two experiments.In the first experiment,we implemented a keyword-based textual IR systemusing Apache Lucene.In the second experiment,we implemented a semantic systemthat uses ontology to store the data and retrieve precise results with high accuracy using SPARQL queries.The keyword-based system has filtered results with 51%accuracy,while the semantic system has filtered results with 95%accuracy,leading to significant improvements in the field and opening up new horizons for researchers.
文摘在小单位,本来已经杂事缠身的你现在又要关注公司的Web网点的建立。怎么办?请考Adobe Systems PageMill3.0。虽然功能不能与Microsoft FrontPage98相匹敌,但PageMill售价比后者低50美元,而且其功能显然也不能等闲视之。PogeMill提供了你需要的稳健易用的工具所具备的重要特性,如果你只是偶尔创建和管理小单位的网点,则该产品是一种不错的选择。
