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文本也能加密——巧用Word Redaction小插件
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作者 吕建新 《少年电脑世界》 2009年第11期54-55,共2页
一提到Word文档的加密,大家就会想到利用“工具”菜单下的“选项”命令进行加密,但此功能只适用通篇文档的加密,而且该密码功能也很容易被人破解。
关键词 文档 加密 文本 “工具”菜单 WORD redaction插件
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Filter and Embedded Feature Selection Methods to Meet Big Data Visualization Challenges
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作者 Kamal A.ElDahshan AbdAllah A.AlHabshy Luay Thamer Mohammed 《Computers, Materials & Continua》 SCIE EI 2023年第1期817-839,共23页
This study focuses on meeting the challenges of big data visualization by using of data reduction methods based the feature selection methods.To reduce the volume of big data and minimize model training time(Tt)while ... This study focuses on meeting the challenges of big data visualization by using of data reduction methods based the feature selection methods.To reduce the volume of big data and minimize model training time(Tt)while maintaining data quality.We contributed to meeting the challenges of big data visualization using the embedded method based“Select from model(SFM)”method by using“Random forest Importance algorithm(RFI)”and comparing it with the filter method by using“Select percentile(SP)”method based chi square“Chi2”tool for selecting the most important features,which are then fed into a classification process using the logistic regression(LR)algorithm and the k-nearest neighbor(KNN)algorithm.Thus,the classification accuracy(AC)performance of LRis also compared to theKNN approach in python on eight data sets to see which method produces the best rating when feature selection methods are applied.Consequently,the study concluded that the feature selection methods have a significant impact on the analysis and visualization of the data after removing the repetitive data and the data that do not affect the goal.After making several comparisons,the study suggests(SFMLR)using SFM based on RFI algorithm for feature selection,with LR algorithm for data classify.The proposal proved its efficacy by comparing its results with recent literature. 展开更多
关键词 Data redaction features selection Select from model Select percentile big data visualization data visualization
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大型平板在高雷诺数下喷气减阻试验研究 被引量:5
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作者 黄红波 何术龙 +3 位作者 高丽瑾 施小勇 张传鸿 薛庆雨 《中国造船》 EI CSCD 北大核心 2018年第1期1-15,共15页
针对船舶减阻,论文采用主动喷射气体减阻方式,在国内循环水槽中首次开展大型平板在高雷诺数条件下喷射气体沿流程方向阻力分布特性及其减阻持续距离的试验研究,考察喷射气体减阻的3个阶段:气泡减阻阶段(bubble drag reduction,BDR),过... 针对船舶减阻,论文采用主动喷射气体减阻方式,在国内循环水槽中首次开展大型平板在高雷诺数条件下喷射气体沿流程方向阻力分布特性及其减阻持续距离的试验研究,考察喷射气体减阻的3个阶段:气泡减阻阶段(bubble drag reduction,BDR),过渡阶段(transition),气层(膜)减阻阶段(air layer drag reduction,ALDR)。试验结果表明,气层(膜)减阻是非常有效及有应用前景的减阻方式。在形成有效气层时,较经济的气层名义厚度约为7~8 mm,在两侧设置50 mm气体逃逸挡板条件下,减阻持续距离可达9 m。根据试验测量结果,在较大气泡直径(毫米级)状态,浮力与升力(剪切力)的比值对气泡的运动扩散有较重要的影响。采用无量纲相似参数vg/u_τ~3可获取形成气层(ALDR)的临界气体流量曲线,为不同雷诺数下精确预报气体流量提供相似性分析的技术手段。 展开更多
关键词 喷气 气泡减阻(babble drag redaction BDR) 气层(膜)减阻(air LAYER dray redaction ALDR) 气层厚度
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Fine-Grained and Fair Identity Authentication Scheme for Mobile Networks Based on Blockchain 被引量:1
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作者 Mengjuan Zhai Yanli Ren +1 位作者 Guorui Feng Xinpeng Zhang 《China Communications》 SCIE CSCD 2022年第6期35-49,共15页
With the popularity of the internet,users hope to better protect their privacy while obtaining network services.However,in the traditional centralized authentication scheme,identity information such as the user's ... With the popularity of the internet,users hope to better protect their privacy while obtaining network services.However,in the traditional centralized authentication scheme,identity information such as the user's private key is generated,stored,and managed by the network operator.Users can't control their identity information,which will lead to a great threat to the privacy of users.Based on redactable blockchain,we propose a fine-grained and fair identity authentication scheme for mobile networks.In our proposed scheme,the user's identity information is generated and controlled by the users.We first propose a notion of score chameleon hash(SCH),which can delete or update the information of illegal users so as to dynamically update the status of users and provide users with more fine-grained and fair services.We propose another notion of self-updating secret sharing(SUSS),which allows users to update the trapdoor and the corresponding hash key after redacting the blockchain without requiring trusted authority to redistribute the trapdoor.Experimental results show that,compared with the immutable blockchain Bitcoin,the redactable blockchain in our identity authentication scheme provides users with fine-grained and fair redacting functions,and can be adopted with a small additional overhead. 展开更多
关键词 identity authentication secret sharing chameleon hash redactable blockchain
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