屏蔽运输容器能够保证放射性废物运输的安全。在我国,高密度聚乙烯高完整容器(HDPE-HIC)作为一种新型货包,暂无专用的屏蔽运输容器,开发一套用于HDPE-HIC的屏蔽运输容器,可防止放射性废物转运、运输过程中对外界产生辐射。在运输过程中...屏蔽运输容器能够保证放射性废物运输的安全。在我国,高密度聚乙烯高完整容器(HDPE-HIC)作为一种新型货包,暂无专用的屏蔽运输容器,开发一套用于HDPE-HIC的屏蔽运输容器,可防止放射性废物转运、运输过程中对外界产生辐射。在运输过程中如果容器出现破损会对外界造成严重的后果,因此对屏蔽运输容器进行跌落和穿刺分析非常重要。本文通过spaceclaim软件建立屏蔽运输容器的三维模型,通过LS-DYNA软件对跌落和穿刺过程进行模拟,得到了屏蔽运输容器最大变形和应变,经分析当前设计能够对内容物进行有效的包容。Shielded transport containers can ensure the safety of radioactive waste transport. In China, high density polyethylene high integrity container (HDPE-HIC) as a new type of cargo package, there is no special shielded transport container, and a set of shielded transport container for HDPE-HIC is developed to prevent radiation to the outside world during the transfer and transportation of radioactive waste. If the container is damaged in the transportation process, it will cause serious consequences to the outside world, so it is very important to analyze the drop and puncture of the shielded transportation container. In this paper, spaceclaim software is used to establish a three-dimensional model of the shielded transport container, and LS-DYNA software is used to simulate the drop and puncture process, and the maximum deformation and strain of the shielded transport container are obtained. After analysis, the current design can effectively contain the contents.展开更多
使用Visual Basic编程,采用正则表达式批量提取由Web of Science导出的Bib Tex题录中所有Keywords字段关键词,按需合并所得关键词的同义词、近义词及词形变化词,然后将出现频度的统计数据写入Excel表,并编制Excel宏自动生成折线图,实现...使用Visual Basic编程,采用正则表达式批量提取由Web of Science导出的Bib Tex题录中所有Keywords字段关键词,按需合并所得关键词的同义词、近义词及词形变化词,然后将出现频度的统计数据写入Excel表,并编制Excel宏自动生成折线图,实现关键词分布的简单可视化。情报工作者后续可借助Excel功能对该程序生成的Excel表执行复杂的数据组合分析,以提高工作效率。展开更多
In this paper, an improved algorithm, web-based keyword weight algorithm （WKWA）, is presented to weight keywords in web documents. WKWA takes into account representation features of web documents and advantages of t...In this paper, an improved algorithm, web-based keyword weight algorithm （WKWA）, is presented to weight keywords in web documents. WKWA takes into account representation features of web documents and advantages of the TF＊IDF, TFC and ITC algorithms in order to make it more appropriate for web documents. Meanwhile, the presented algorithm is applied to improved vector space model （IVSM）. A real system has been implemented for calculating semantic similarities of web documents. Four experiments have been carried out. They are keyword weight calculation, feature item selection, semantic similarity calculation, and WKWA time performance. The results demonstrate accuracy of keyword weight, and semantic similarity is improved.展开更多
To save the local storage,users store the data on the cloud server who offers convenient internet services.To guarantee the data privacy,users encrypt the data before uploading them into the cloud server.Since encrypt...To save the local storage,users store the data on the cloud server who offers convenient internet services.To guarantee the data privacy,users encrypt the data before uploading them into the cloud server.Since encryption can reduce the data availability,public-key encryption with keyword search(PEKS)is developed to achieve the retrieval of the encrypted data without decrypting them.However,most PEKS schemes cannot resist quantum computing attack,because the corresponding hardness assumptions are some number theory problems that can be solved efficiently under quantum computers.Besides,the traditional PEKS schemes have an inherent security issue that they cannot resist inside keywords guessing attack(KGA).In this attack,a malicious server can guess the keywords encapsulated in the search token by computing the ciphertext of keywords exhaustively and performing the test between the token and the ciphertext of keywords.In the paper,we propose a lattice-based PEKS scheme that can resist quantum computing attacks.To resist inside KGA,this scheme adopts a lattice-based signature technique into the encryption of keywords to prevent the malicious server from forging a valid ciphertext.Finally,some simulation experiments are conducted to demonstrate the performance of the proposed scheme and some comparison results are further shown with respect to other searchable schemes.展开更多
A search strategy over encrypted cloud data based on keywords has been improved and has presented a method using different strategies on the client and the server to improve the search efficiency in this paper. The cl...A search strategy over encrypted cloud data based on keywords has been improved and has presented a method using different strategies on the client and the server to improve the search efficiency in this paper. The client uses the Chinese and English to achieve the synonym construction of the keywords, the establishment of the fuzzy-syllable words and synonyms set of keywords and the implementation of fuzzy search strategy over the encryption of cloud data based on keywords. The server side through the analysis of the user’s query request provides keywords for users to choose and topic words and secondary words are picked out. System will match topic words with historical inquiry in time order, and then the new query result of the request is directly gained. The analysis of the simulation experiment shows that the fuzzy search strategy can make better use of historical results on the basis of privacy protection for the realization of efficient data search, saving the search time and improving the efficiency of search.展开更多
Keywords with the retrieval value clearly show the main contents, enhance the influence of academic periodicals, highlight specific information, and generalize information, but because of the ignorance of the value of...Keywords with the retrieval value clearly show the main contents, enhance the influence of academic periodicals, highlight specific information, and generalize information, but because of the ignorance of the value of keywords from some authors and editors, the lack of canonical guidance, and limitations of the editorial knowledge structure, there are some problems concerning keywords in academic papers, such as papers containing too many or too few keywords, or keywords being used in a way that is too general or colloquial. According to academic principle, accurate principle, logical principle, comprehensive principle, it is imperative to discuss how to choose keywords properly.展开更多
文摘屏蔽运输容器能够保证放射性废物运输的安全。在我国,高密度聚乙烯高完整容器(HDPE-HIC)作为一种新型货包,暂无专用的屏蔽运输容器,开发一套用于HDPE-HIC的屏蔽运输容器,可防止放射性废物转运、运输过程中对外界产生辐射。在运输过程中如果容器出现破损会对外界造成严重的后果,因此对屏蔽运输容器进行跌落和穿刺分析非常重要。本文通过spaceclaim软件建立屏蔽运输容器的三维模型,通过LS-DYNA软件对跌落和穿刺过程进行模拟,得到了屏蔽运输容器最大变形和应变,经分析当前设计能够对内容物进行有效的包容。Shielded transport containers can ensure the safety of radioactive waste transport. In China, high density polyethylene high integrity container (HDPE-HIC) as a new type of cargo package, there is no special shielded transport container, and a set of shielded transport container for HDPE-HIC is developed to prevent radiation to the outside world during the transfer and transportation of radioactive waste. If the container is damaged in the transportation process, it will cause serious consequences to the outside world, so it is very important to analyze the drop and puncture of the shielded transportation container. In this paper, spaceclaim software is used to establish a three-dimensional model of the shielded transport container, and LS-DYNA software is used to simulate the drop and puncture process, and the maximum deformation and strain of the shielded transport container are obtained. After analysis, the current design can effectively contain the contents.
文摘使用Visual Basic编程,采用正则表达式批量提取由Web of Science导出的Bib Tex题录中所有Keywords字段关键词,按需合并所得关键词的同义词、近义词及词形变化词,然后将出现频度的统计数据写入Excel表,并编制Excel宏自动生成折线图,实现关键词分布的简单可视化。情报工作者后续可借助Excel功能对该程序生成的Excel表执行复杂的数据组合分析,以提高工作效率。
基金Project supported by the Science Foundation of Shanghai Municipal Commission of Science and Technology （Grant No.055115001）
文摘In this paper, an improved algorithm, web-based keyword weight algorithm （WKWA）, is presented to weight keywords in web documents. WKWA takes into account representation features of web documents and advantages of the TF＊IDF, TFC and ITC algorithms in order to make it more appropriate for web documents. Meanwhile, the presented algorithm is applied to improved vector space model （IVSM）. A real system has been implemented for calculating semantic similarities of web documents. Four experiments have been carried out. They are keyword weight calculation, feature item selection, semantic similarity calculation, and WKWA time performance. The results demonstrate accuracy of keyword weight, and semantic similarity is improved.
基金The authors would like to thank the support from Fundamental Research Funds for the Central Universities(No.30918012204)The authors also gratefully acknowledge the helpful comments and suggestions of other researchers,which has improved the presentation.
文摘To save the local storage,users store the data on the cloud server who offers convenient internet services.To guarantee the data privacy,users encrypt the data before uploading them into the cloud server.Since encryption can reduce the data availability,public-key encryption with keyword search(PEKS)is developed to achieve the retrieval of the encrypted data without decrypting them.However,most PEKS schemes cannot resist quantum computing attack,because the corresponding hardness assumptions are some number theory problems that can be solved efficiently under quantum computers.Besides,the traditional PEKS schemes have an inherent security issue that they cannot resist inside keywords guessing attack(KGA).In this attack,a malicious server can guess the keywords encapsulated in the search token by computing the ciphertext of keywords exhaustively and performing the test between the token and the ciphertext of keywords.In the paper,we propose a lattice-based PEKS scheme that can resist quantum computing attacks.To resist inside KGA,this scheme adopts a lattice-based signature technique into the encryption of keywords to prevent the malicious server from forging a valid ciphertext.Finally,some simulation experiments are conducted to demonstrate the performance of the proposed scheme and some comparison results are further shown with respect to other searchable schemes.
文摘A search strategy over encrypted cloud data based on keywords has been improved and has presented a method using different strategies on the client and the server to improve the search efficiency in this paper. The client uses the Chinese and English to achieve the synonym construction of the keywords, the establishment of the fuzzy-syllable words and synonyms set of keywords and the implementation of fuzzy search strategy over the encryption of cloud data based on keywords. The server side through the analysis of the user’s query request provides keywords for users to choose and topic words and secondary words are picked out. System will match topic words with historical inquiry in time order, and then the new query result of the request is directly gained. The analysis of the simulation experiment shows that the fuzzy search strategy can make better use of historical results on the basis of privacy protection for the realization of efficient data search, saving the search time and improving the efficiency of search.
文摘Keywords with the retrieval value clearly show the main contents, enhance the influence of academic periodicals, highlight specific information, and generalize information, but because of the ignorance of the value of keywords from some authors and editors, the lack of canonical guidance, and limitations of the editorial knowledge structure, there are some problems concerning keywords in academic papers, such as papers containing too many or too few keywords, or keywords being used in a way that is too general or colloquial. According to academic principle, accurate principle, logical principle, comprehensive principle, it is imperative to discuss how to choose keywords properly.
