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可控构建Co_(3)S_(4)@CoMoS核@壳材料用于氢溢流促进的高效加氢脱硫
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作者 鲍文静 冯超 +9 位作者 马书妍 闫登伟 张聪 岳长乐 王崇泽 郭海玲 王继乾 孙道峰 柳云骐 卢玉坤 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第2期154-170,共17页
过去几十年,通过催化加氢脱硫(HDS)实现超清洁油品的生产一直是石油炼制领域的研究重点.然而,常规的HDS催化剂因金属负载量较低及金属与载体之间的强相互作用,导致其对4,6-二甲基二苯并噻吩(4,6-DMDBT)类大分子的脱除效率较低.这类大分... 过去几十年,通过催化加氢脱硫(HDS)实现超清洁油品的生产一直是石油炼制领域的研究重点.然而,常规的HDS催化剂因金属负载量较低及金属与载体之间的强相互作用,导致其对4,6-二甲基二苯并噻吩(4,6-DMDBT)类大分子的脱除效率较低.这类大分子反应物由于具有较大的空间位阻,使得其在催化剂表面活性位点上的吸附和反应更为困难,往往通过氢化反应进行脱硫反应.因此,为实现有效的脱硫反应,必须发展能高效解离和活化氢物种的催化剂.此外,通过氢化反应高效地脱除4,6-DMDBT通常需要在高温高压等苛刻条件下进行,这要求催化剂具备更高的活性、选择性和稳定性.为解决上述问题,本文通过奥斯瓦尔德熟化法制备了一种由多孔CoMoS外壳和Co_(3)S_(4)内核构成的Co_(3)S_(4)@CoMoS核@壳材料,并用于4,6-DMDBT类大分子的脱除.同时,通过原位表征和理论计算研究了该催化材料在HDS反应中的构效关系.SEM结果显示,制得的Co_(3)S_(4)@CoMoS空心球外表面粗糙,由许多小纳米颗粒组成.TEM图像直观地显示了Co_(3)S_(4)@CoMoS催化剂的结构,其外壳和间隙厚度分别为80和100 nm,高度多孔的球体使核@壳材料能够提供较短的氢溢流距离,从而构建了一种高效的HDS纳米反应器.EDX结果显示Co,Mo和S元素在Co_(3)S_(4)@CoMoS催化剂上均匀分布.其中,Mo金属仅存在于纳米球的外壳上;除外层的CoMoS相外,Co元素还形成了一个由Co-S物种组成的独立核心.结合XRD结果可以确定,该催化剂是由Co促进的MoS_(2)外壳和Co_(3)S_(4)内核组成的Co_(3)S_(4)@CoMoS核@壳材料.电镜图像和氮气吸脱附等结果表明,Co_(3)S_(4)@CoMoS纳米球的外壳由(Co)MoS_(2)纳米片交错卷曲组装而成,壳层含有丰富的活性位点和发达的孔道结构,为反应物提供了充足的吸附位点.Co金属的掺杂增加了MoS_(2)晶体的无序度,使得MoS_(2)纳米片上形成了大量的不饱和硫空位.钴原子锚定在MoS_(2)边缘还可以抑制MoS_(2)纳米片的团聚,使得Co_(3)S_(4)@CoMoS催化剂上的层状MoS_(2)长度较短且堆叠层数较低,有利于活性位点的充分暴露.H_(2)-程序升温脱附和WO_(3)变色实验结果证实了Co_(3)S_(4)@CoMoS结构中的氢溢流效应.HDS实验结果表明,仅使用30 mg Co_(3)S_(4)@CoMoS催化剂就能够实现99.2%的二苯并噻吩转化率和94.9%的4,6-DMDBT转化率.推测在HDS反应中,含硫大分子锚定在CoMoS外壳的硫空位上,而内核Co_(3)S_(4)相能够引发氢溢流效应,并将活性氢物种传递给CoMoS相,用于吸附和脱除含硫反应物,从而在HDS反应中使CoMoS和Co_(3)S_(4)两相起到协同作用,进而实现针对4,6-DMDBT类大分子的深度加氢脱硫.同时,反应过程中小分子H_(2)则可以自由地通过壳体扩散到内核的Co_(3)S_(4)相上,被解离成溢流氢物种后又传递给外层壳体,使得硫空位在HDS中不断地形成和再生.此外,核@壳球体内部连续的介孔通道缩短了溢流氢物种的迁移距离,提高了活性物种的利用率.致密的壳体使催化剂在多次循环反应中保留了核@壳结构,提高了催化剂的使用寿命.理论计算结果表明,CoMoS相和Co_(3)S_(4)相间的强电荷转移增加了CoMoS相中硫原子的电子云密度,有利于反应物在活性物种上的吸附.此外,得益于Co_(3)S_(4)相的氢溢流效应,在CoMoS/Co_(3)S_(4)双相结构上的氢解离能远低于单相结构,这使得H2分子能够在核@壳催化剂上被快速活化,以促进反应物分子的下一步脱硫进程.综上所述,本文制备的多组分Co_(3)S_(4)@CoMoS核@壳催化剂表现出较好的加氢脱硫性能.文章还提出了活性相结构与催化活性及反应路径选择性之间的作用机制,为进一步开发高效非负载加氢脱硫催化剂提供了新思路. 展开更多
关键词 加氢脱硫 氢溢流效应 @壳结构 CoMoS活性相 双活性相协同
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同轴电缆用超疏水二氧化硅@石英纤维复合材料的性能研究
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作者 张港澳 秦宗益 +6 位作者 张亚闪 侯成义 张青红 李耀刚 靳志杰 王宏志 李克睿 《东华大学学报(自然科学版)》 CAS 北大核心 2024年第4期63-67,共5页
具有低介电常数的SiO_(2)复合材料在低介电和隔热保温材料领域有着广阔的应用前景,但SiO_(2)复合材料在实际应用中存在吸水性强、保存条件苛刻等问题。使用疏水改性剂(六甲基二硅氮烷(HMDS)、硬脂酸、十二烷基硫酸钠)对SiO_(2)@石英纤... 具有低介电常数的SiO_(2)复合材料在低介电和隔热保温材料领域有着广阔的应用前景,但SiO_(2)复合材料在实际应用中存在吸水性强、保存条件苛刻等问题。使用疏水改性剂(六甲基二硅氮烷(HMDS)、硬脂酸、十二烷基硫酸钠)对SiO_(2)@石英纤维复合材料进行改性,研究疏水改性剂类型及质量分数对复合材料疏水性能和介电性能的影响。结果表明,3%的HMDS改性复合材料的疏水改性效果最好(接触角为151.6°),保存240d后接触角最低为132.6°,200℃煅烧后复合材料的介电常数低至1.87。将疏水改性SiO_(2)@石英纤维复合材料制成同轴通信电缆,所得电缆的电压驻波比为1.48,衰减值为1.56dB,特性阻抗为48Ω。疏水改性复合材料具有优异的电缆性能,在通信电缆等领域展示出潜在的应用价值。 展开更多
关键词 SiO_(2)@石英纤维复合材料 低介电常数 疏水改性 同轴电缆
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Cu_(2)O@AuCC纳米酶杀菌剂的制备及其在果蔬保鲜中的应用
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作者 赵世雯 申峰 +5 位作者 王单阳 綦仕鹏 佘昕阳 张钊 李建科 张玉环 《食品安全质量检测学报》 CAS 2024年第14期267-274,共8页
目的开发一种新型纳米酶杀菌剂,以解决现有纳米酶在果蔬保鲜中杀菌性能不足的问题,推动其在食品保鲜领域的应用。方法利用自牺牲模板技术制备了核@笼结构的Cu_(2)O@AuCC纳米酶,并通过多种表征手段确认了其微观结构。利用平板计数法评估... 目的开发一种新型纳米酶杀菌剂,以解决现有纳米酶在果蔬保鲜中杀菌性能不足的问题,推动其在食品保鲜领域的应用。方法利用自牺牲模板技术制备了核@笼结构的Cu_(2)O@AuCC纳米酶,并通过多种表征手段确认了其微观结构。利用平板计数法评估了该纳米酶对两种常见食源性致病菌的抗菌性能。利用显微镜技术监测了杀菌过程中细菌的形态变化和细胞膜的完整性。此外,通过在圣女果和葡萄上的保鲜应用测试,验证了材料的实用保鲜性能。结果Cu_(2)O@AuCC通过释放Cu^(+)和催化含氧自由基生成的机制,实现对大肠杆菌(Escherichia coli)和金黄色葡萄球菌(Staphylococcus aureus)99.99%的杀灭率。水果保鲜实验结果表明Cu_(2)O@AuCC能够有效抑制微生物污染并延缓水果腐败。结论Cu_(2)O@AuCC显著延长了果蔬的保鲜时间,这种新型材料的发现为纳米酶在食品保鲜领域的应用奠定了基础。 展开更多
关键词 纳米酶 @笼结构 生物安全性 果蔬保鲜
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Certis: Cloud Asset Management & Threat Evaluation Using Behavioral Fingerprinting at Application Layer
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作者 Kumardwij Bhatnagar Vijay K. Madisetti 《Journal of Software Engineering and Applications》 2024年第6期474-486,共13页
This paper introduces Certis, a powerful framework that addresses the challenges of cloud asset tracking, management, and threat detection in modern cybersecurity landscapes. It enhances asset identification and anoma... This paper introduces Certis, a powerful framework that addresses the challenges of cloud asset tracking, management, and threat detection in modern cybersecurity landscapes. It enhances asset identification and anomaly detection through SSL certificate parsing, cloud service provider integration, and advanced fingerprinting techniques like JARM at the application layer. Current work will focus on cross-layer malicious behavior identification to further enhance its capabilities, including minimizing false positives through AI-based learning techniques. Certis promises to offer a powerful solution for organizations seeking proactive cybersecurity defenses in the face of evolving threats. 展开更多
关键词 Certis SSL Certificate Parsing JARM fingerprinting Anomaly Detection Proactive Defense
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Rational and Continuous Measurement of Emotional-Fingerprint, Emotional-Quotient and Categorical vs Proportional Recognition of Facial Emotions with M.A.R.I.E., Second Half
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作者 Philippe Granato Shreekumar Vinekar +1 位作者 Jean-Pierre Van Gansberghe Raymond Bruyer 《Open Journal of Psychiatry》 2024年第4期400-450,共51页
Context: The advent of Artificial Intelligence (AI) requires modeling prior to its implementation in algorithms for most human skills. This observation requires us to have a detailed and precise understanding of the i... Context: The advent of Artificial Intelligence (AI) requires modeling prior to its implementation in algorithms for most human skills. This observation requires us to have a detailed and precise understanding of the interfaces of verbal and emotional communications. The progress of AI is significant on the verbal level but modest in terms of the recognition of facial emotions even if this functionality is one of the oldest in humans and is omnipresent in our daily lives. Dysfunction in the ability for facial emotional expressions is present in many brain pathologies encountered by psychiatrists, neurologists, psychotherapists, mental health professionals including social workers. It cannot be objectively verified and measured due to a lack of reliable tools that are valid and consistently sensitive. Indeed, the articles in the scientific literature dealing with Visual-Facial-Emotions-Recognition (ViFaEmRe), suffer from the absence of 1) consensual and rational tools for continuous quantified measurement, 2) operational concepts. We have invented a software that can use computer-morphing attempting to respond to these two obstacles. It is identified as the Method of Analysis and Research of the Integration of Emotions (M.A.R.I.E.). Our primary goal is to use M.A.R.I.E. to understand the physiology of ViFaEmRe in normal healthy subjects by standardizing the measurements. Then, it will allow us to focus on subjects manifesting abnormalities in this ability. Our second goal is to make our contribution to the progress of AI hoping to add the dimension of recognition of facial emotional expressions. Objective: To study: 1) categorical vs dimensional aspects of recognition of ViFaEmRe, 2) universality vs idiosyncrasy, 3) immediate vs ambivalent Emotional-Decision-Making, 4) the Emotional-Fingerprint of a face and 5) creation of population references data. Methods: M.A.R.I.E. enables the rational, quantified measurement of Emotional Visual Acuity (EVA) in an individual observer and a population aged 20 to 70 years. Meanwhile, it can measure the range and intensity of expressed emotions through three Face- Tests, quantify the performance of a sample of 204 observers with hypernormal measures of cognition, “thymia” (defined elsewhere), and low levels of anxiety, and perform analysis of the six primary emotions. Results: We have individualized the following continuous parameters: 1) “Emotional-Visual- Acuity”, 2) “Visual-Emotional-Feeling”, 3) “Emotional-Quotient”, 4) “Emotional-Decision-Making”, 5) “Emotional-Decision-Making Graph” or “Individual-Gun-Trigger”, 6) “Emotional-Fingerprint” or “Key-graph”, 7) “Emotional-Fingerprint-Graph”, 8) detecting “misunderstanding” and 9) detecting “error”. This allowed us a taxonomy with coding of the face-emotion pair. Each face has specific measurements and graphics. The EVA improves from ages of 20 to 55 years, then decreases. It does not depend on the sex of the observer, nor the face studied. In addition, 1% of people endowed with normal intelligence do not recognize emotions. The categorical dimension is a variable for everyone. The range and intensity of ViFaEmRe is idiosyncratic and not universally uniform. The recognition of emotions is purely categorical for a single individual. It is dimensional for a population sample. Conclusions: Firstly, M.A.R.I.E. has made possible to bring out new concepts and new continuous measurements variables. The comparison between healthy and abnormal individuals makes it possible to take into consideration the significance of this line of study. From now on, these new functional parameters will allow us to identify and name “emotional” disorders or illnesses which can give additional dimension to behavioral disorders in all pathologies that affect the brain. Secondly, the ViFaEmRe is idiosyncratic, categorical, and a function of the identity of the observer and of the observed face. These findings stack up against Artificial Intelligence, which cannot have a globalist or regionalist algorithm that can be programmed into a robot, nor can AI compete with human abilities and judgment in this domain. *Here “Emotional disorders” refers to disorders of emotional expressions and recognition. 展开更多
关键词 M.A.R.I.E. Universality Idiosyncrasy Measurement of Emotional Quotient Emotional fingerprint Emotional Decision-Making Limbic Lobe
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用于C_(3)H_(6)/N_(2)分离的PDA@PEBA2533膜的制备
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作者 杜翠花 张茜 +2 位作者 王晓东 黄伟 周明 《化工进展》 EI CAS CSCD 北大核心 2024年第1期437-446,共10页
为回收聚丙烯制备尾气中的丙烯,采用本实验室独创的浸渍-旋转法在聚醚嵌段共聚酰胺(PEBA2533)膜表面沉积聚多巴胺(PDA)膜层制备出对C3H6具有更强亲和性的PDA@PEBA2533膜。利用扫描电子显微镜(SEM)和X射线衍射(XRD)对PDA颗粒和膜进行表... 为回收聚丙烯制备尾气中的丙烯,采用本实验室独创的浸渍-旋转法在聚醚嵌段共聚酰胺(PEBA2533)膜表面沉积聚多巴胺(PDA)膜层制备出对C3H6具有更强亲和性的PDA@PEBA2533膜。利用扫描电子显微镜(SEM)和X射线衍射(XRD)对PDA颗粒和膜进行表征。考察了PDA沉积时间对膜形貌、结构以及分离性能的影响,也考察了温度和压力等操作条件对膜分离性能的影响。探索了PDA@PEBA2533膜对不同C3H6浓度的C_(3)H_(6)/N_(2)混合气的分离效果以及膜的长时间分离稳定性。结果表明,沉积PDA于PEBA2533膜表面有效提高了膜的分离性能。当沉积时间不小于24h时,可得到连续的PDA膜层,随沉积时间的增加,膜层逐渐增厚,气体渗透速率先增大后减小,选择性持续上升,沉积24h所制备的膜分离性能最佳。增大操作温度和压力,膜对C3H6和N2的渗透速率均增大,C_(3)H_(6)/N_(2)选择性则降低。增大混合气中C3H6浓度,膜对C3H6的渗透速率和选择性均呈现先上升后下降的趋势。在所制备的分离性能最好的PDA@PEBA2533膜上,0.2MPa时,对C3H6体积分数为20%的混合气,温度从0℃提高到50℃,C3H6渗透速率从8.25GPU增加到71.42GPU,C_(3)H_(6)/N_(2)选择性从22.92降低至10.14。在130h的气体分离实验中,该膜表现出良好的稳定性。该膜与其他分离C_(3)H_(6)/N_(2)混合气膜相比具有一定的优势。 展开更多
关键词 C_(3)H_(6)/N_(2)混合气 分离 浸渍-旋转法 聚多巴胺@聚醚嵌段共聚酰胺
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Geographical origin identification of winter jujube(Ziziphus jujuba Dongzao')by using multi-element fingerprinting with chemometrics
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作者 Xiabing Kong Qiusheng Chen +8 位作者 Min Xu Yihui Liu Xiaoming Li Lingxi Han Qiang Zhang Haoliang Wan Lu Liu Xubo Zhao Jiyun Nie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1749-1762,共14页
Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 16... Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits. 展开更多
关键词 winter jujube multi-element fingerprint analysis CHEMOMETRICS origin traceability
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An Image Fingerprint and Attention Mechanism Based Load Estimation Algorithm for Electric Power System
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作者 Qing Zhu Linlin Gu Huijie Lin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期577-591,共15页
With the rapid development of electric power systems,load estimation plays an important role in system operation and planning.Usually,load estimation techniques contain traditional,time series,regression analysis-base... With the rapid development of electric power systems,load estimation plays an important role in system operation and planning.Usually,load estimation techniques contain traditional,time series,regression analysis-based,and machine learning-based estimation.Since the machine learning-based method can lead to better performance,in this paper,a deep learning-based load estimation algorithm using image fingerprint and attention mechanism is proposed.First,an image fingerprint construction is proposed for training data.After the data preprocessing,the training data matrix is constructed by the cyclic shift and cubic spline interpolation.Then,the linear mapping and the gray-color transformation method are proposed to form the color image fingerprint.Second,a convolutional neural network(CNN)combined with an attentionmechanism is proposed for training performance improvement.At last,an experiment is carried out to evaluate the estimation performance.Compared with the support vector machine method,CNN method and long short-term memory method,the proposed algorithm has the best load estimation performance. 展开更多
关键词 Load estimation deep learning attention mechanism image fingerprint construction
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A UWB/IMU-Assisted Fingerprinting Localization Framework with Low Human Efforts
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作者 Pan Hao Chen Yu +1 位作者 Qi Xiaogang Liu Meili 《China Communications》 SCIE CSCD 2024年第6期40-52,共13页
With the rapid development of smart phone,the location-based services(LBS)have received great attention in the past decades.Owing to the widespread use of WiFi and Bluetooth devices,Received Signal Strength Indication... With the rapid development of smart phone,the location-based services(LBS)have received great attention in the past decades.Owing to the widespread use of WiFi and Bluetooth devices,Received Signal Strength Indication(RSSI)fingerprintbased localization method has obtained much development in both academia and industries.In this work,we introduce an efficient way to reduce the labor-intensive site survey process,which uses an UWB/IMU-assisted fingerprint construction(UAFC)and localization framework based on the principle of Automatic radio map generation scheme(ARMGS)is proposed to replace the traditional manual measurement.To be specific,UWB devices are employed to estimate the coordinates when the collector is moved in a reference point(RP).An anchor self-localization method is investigated to further reduce manual measurement work in a wide and complex environment,which is also a grueling,time-consuming process that is lead to artificial errors.Moreover,the measurements of IMU are incorporated into the UWB localization algorithm and improve the label accuracy in fingerprint.In addition,the weighted k-nearest neighbor(WKNN)algorithm is applied to online localization phase.Finally,filed experiments are carried out and the results confirm the effectiveness of the proposed approach. 展开更多
关键词 indoor localization machine learning ultra wideband WiFi fingerprint
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CMAES-WFD:Adversarial Website Fingerprinting Defense Based on Covariance Matrix Adaptation Evolution Strategy
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作者 Di Wang Yuefei Zhu +1 位作者 Jinlong Fei Maohua Guo 《Computers, Materials & Continua》 SCIE EI 2024年第5期2253-2276,共24页
Website fingerprinting,also known asWF,is a traffic analysis attack that enables local eavesdroppers to infer a user’s browsing destination,even when using the Tor anonymity network.While advanced attacks based on de... Website fingerprinting,also known asWF,is a traffic analysis attack that enables local eavesdroppers to infer a user’s browsing destination,even when using the Tor anonymity network.While advanced attacks based on deep neural network(DNN)can performfeature engineering and attain accuracy rates of over 98%,research has demonstrated thatDNNis vulnerable to adversarial samples.As a result,many researchers have explored using adversarial samples as a defense mechanism against DNN-based WF attacks and have achieved considerable success.However,these methods suffer from high bandwidth overhead or require access to the target model,which is unrealistic.This paper proposes CMAES-WFD,a black-box WF defense based on adversarial samples.The process of generating adversarial examples is transformed into a constrained optimization problem solved by utilizing the Covariance Matrix Adaptation Evolution Strategy(CMAES)optimization algorithm.Perturbations are injected into the local parts of the original traffic to control bandwidth overhead.According to the experiment results,CMAES-WFD was able to significantly decrease the accuracy of Deep Fingerprinting(DF)and VarCnn to below 8.3%and the bandwidth overhead to a maximum of only 14.6%and 20.5%,respectively.Specially,for Automated Website Fingerprinting(AWF)with simple structure,CMAES-WFD reduced the classification accuracy to only 6.7%and the bandwidth overhead to less than 7.4%.Moreover,it was demonstrated that CMAES-WFD was robust against adversarial training to a certain extent. 展开更多
关键词 Traffic analysis deep neural network adversarial sample TOR website fingerprinting
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BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things
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作者 Yu Zhang Bei Gong Qian Wang 《Digital Communications and Networks》 SCIE CSCD 2024年第3期728-739,共12页
The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security risks.As a network-level security authentication method,device fingerprin... The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security risks.As a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access phases.However,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or types.To address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this paper.The mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint dataset.The complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using BLS.The experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods. 展开更多
关键词 Device fingerprint Traffic analysis Class imbalance Broad learning system Access authentication
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An Active Deception Defense Model Based on Address Mutation and Fingerprint Camouflage
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作者 Wang Shuo Chu Jiang +3 位作者 Pei Qingqi Shao Feng Yuan Shuai Zhong Xiaoge 《China Communications》 SCIE CSCD 2024年第7期212-223,共12页
The static and predictable characteristics of cyber systems give attackers an asymmetric advantage in gathering useful information and launching attacks.To reverse this asymmetric advantage,a new defense idea,called M... The static and predictable characteristics of cyber systems give attackers an asymmetric advantage in gathering useful information and launching attacks.To reverse this asymmetric advantage,a new defense idea,called Moving Target Defense(MTD),has been proposed to provide additional selectable measures to complement traditional defense.However,MTD is unable to defeat the sophisticated attacker with fingerprint tracking ability.To overcome this limitation,we go one step beyond and show that the combination of MTD and Deception-based Cyber Defense(DCD)can achieve higher performance than either of them.In particular,we first introduce and formalize a novel attacker model named Scan and Foothold Attack(SFA)based on cyber kill chain.Afterwards,we develop probabilistic models for SFA defenses to provide a deeper analysis of the theoretical effect under different defense strategies.These models quantify attack success probability and the probability that the attacker will be deceived under various conditions,such as the size of address space,and the number of hosts,attack analysis time.Finally,the experimental results show that the actual defense effect of each strategy almost perfectly follows its probabilistic model.Also,the defense strategy of combining address mutation and fingerprint camouflage can achieve a better defense effect than the single address mutation. 展开更多
关键词 address mutation deception defense fingerprint camouflage moving target defense probabilistic model
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Analysis of GC×GC fingerprints from medicinal materials using a novel contour detection algorithm:A case of Curcuma wenyujin
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作者 Xinyue Yang Yingyu Sima +2 位作者 Xuhuai Luo Yaping Li Min He 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期542-551,共10页
This study introduces an innovative contour detection algorithm,PeakCET,designed for rapid and efficient analysis of natural product image fingerprints using comprehensive two-dimensional gas chromatogram(GC×GC).... This study introduces an innovative contour detection algorithm,PeakCET,designed for rapid and efficient analysis of natural product image fingerprints using comprehensive two-dimensional gas chromatogram(GC×GC).This method innovatively combines contour edge tracking with affinity propagation(AP)clustering for peak detection in GC×GC fingerprints,the first in this field.Contour edge tracking signif-icantly reduces false positives caused by“burr”signals,while AP clustering enhances detection accuracy in the face of false negatives.The efficacy of this approach is demonstrated using three medicinal products derived from Curcuma wenyujin.PeakCET not only performs contour detection but also employs inter-group peak matching and peak-volume percentage calculations to assess the compositional similarities and differences among various samples.Furthermore,this algorithm compares the GC×GC fingerprints of Radix/Rhizoma Curcumae Wenyujin with those of products from different botanical origins.The findings reveal that genetic and geographical factors influence the accumulation of secondary metabolites in various plant tissues.Each sample exhibits unique characteristic components alongside common ones,and vari-ations in content may influence their therapeutic effectiveness.This research establishes a foundational data-set for the quality assessment of Curcuma products and paves the way for the application of computer vision techniques in two-dimensional(2D)fingerprint analysis of GC×GC data. 展开更多
关键词 GC×GC Image fingerprints Contour detection Clustering of mass spectra Curcuma products
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AWeb Application Fingerprint Recognition Method Based on Machine Learning
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作者 Yanmei Shi Wei Yu +1 位作者 Yanxia Zhao Yungang Jia 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期887-906,共20页
Web application fingerprint recognition is an effective security technology designed to identify and classify web applications,thereby enhancing the detection of potential threats and attacks.Traditional fingerprint r... Web application fingerprint recognition is an effective security technology designed to identify and classify web applications,thereby enhancing the detection of potential threats and attacks.Traditional fingerprint recognition methods,which rely on preannotated feature matching,face inherent limitations due to the ever-evolving nature and diverse landscape of web applications.In response to these challenges,this work proposes an innovative web application fingerprint recognition method founded on clustering techniques.The method involves extensive data collection from the Tranco List,employing adjusted feature selection built upon Wappalyzer and noise reduction through truncated SVD dimensionality reduction.The core of the methodology lies in the application of the unsupervised OPTICS clustering algorithm,eliminating the need for preannotated labels.By transforming web applications into feature vectors and leveraging clustering algorithms,our approach accurately categorizes diverse web applications,providing comprehensive and precise fingerprint recognition.The experimental results,which are obtained on a dataset featuring various web application types,affirm the efficacy of the method,demonstrating its ability to achieve high accuracy and broad coverage.This novel approach not only distinguishes between different web application types effectively but also demonstrates superiority in terms of classification accuracy and coverage,offering a robust solution to the challenges of web application fingerprint recognition. 展开更多
关键词 Web application fingerprint recognition unsupervised learning clustering algorithm feature extraction automated testing network security
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Fingerprint Study of Polygonati Rhizoma with Steaming and Exposing to the Sun Alternatively for Different Times
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作者 Min WANG Chenying YE +3 位作者 Qian WANG Ting HE Shenggao YIN Gailian ZHOU 《Medicinal Plant》 2024年第2期18-20,共3页
[Objectives]To explore the influence of different times of steaming and exposing to the sun on the fingerprint of Polygonati Rhizoma by studying the HPLC fingerprint of Polygonati Rhizoma processed products with diffe... [Objectives]To explore the influence of different times of steaming and exposing to the sun on the fingerprint of Polygonati Rhizoma by studying the HPLC fingerprint of Polygonati Rhizoma processed products with different times of steaming and exposing to the sun,and to provide a basis for the determination of the best processing technology of Polygonati Rhizoma.[Methods]SETSAIL II AQ-C 18(5μm×250 mm×4.6 mm)was used as the column,the column temperature was 30℃,pure water(A)and acetonitrile(B)were eluted gradually,0-10 min,B(5%-10%),10-30 min,B(10%-35%),30-40 min,B(35%-60%),40-45 min,B(60%-100%),flow rate 1 mL/min,absorption wavelength 200 nm.[Results]The relative retained peak area RSDs of the common peaks in the precision,reproducibility and stability tests were all less than 5%.There were 17 common peaks in the fingerprint of nine batches of samples,and the retention time of Peak 2 was basically the same as that of the reference peak of 5-HMF.Peak 4 mainly existed in the chromatogram of Sample 3 to Sample 5,peaks 5 and 11 mainly existed after Sample 3,peaks 9,14 and 16 mainly existed after Sample 6,and peaks 12 and 17 mainly existed after Sample 4.[Conclusions]A total of 17 common peaks were obtained,and the Peak 2 was the designated peak,and the chemical components of each processed product were different. 展开更多
关键词 Polygonati Rhizoma PROCESSING HPLC fingerprint
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Improving Optimal Fingerprinting Methods Requires a Viewpoint beyond Statistical Science
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作者 Jianhua LU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1869-1872,共4页
While being successful in the detection and attribution of climate change,the optimal fingerprinting method(OFM)may have some limitations from a physics-and-dynamics-based viewpoint.Here,an analysis is made on the lin... While being successful in the detection and attribution of climate change,the optimal fingerprinting method(OFM)may have some limitations from a physics-and-dynamics-based viewpoint.Here,an analysis is made on the linearity,noninteraction,and stationary-variability assumptions adopted by OFM.It is suggested that furthering OFM needs a viewpoint beyond statistical science,and the method should be combined with theoretical tools in the dynamics and physics of the Earth system,so as to be applied for the detection and attribution of nonlinear climate change including tipping elements within the Earth system. 展开更多
关键词 optimal fingerprinting detection and attribution NONLINEARITY interaction between climate change and variability non-stationary climate variability
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UV,five wavelengths fusion and electrochemical fingerprints combined with antioxidant activity for quality control of antiviral mixture
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作者 Kaining Zhou Zini Tang +2 位作者 Guoxiang Sun Ping Guo Lili Lan 《Asian Journal of Traditional Medicines》 2024年第3期119-136,151,共19页
Aiming to ensure the consistency of quality control of Traditional Chinese Medicines(TCMs),a combination method of high-performance liquid chromatography(HPLC),ultraviolet(UV),electrochemical(EC)was developed in this ... Aiming to ensure the consistency of quality control of Traditional Chinese Medicines(TCMs),a combination method of high-performance liquid chromatography(HPLC),ultraviolet(UV),electrochemical(EC)was developed in this study to comprehensively evaluate the quality of Antiviral Mixture(AM),and Comprehensive Linear Quantification Fingerprint Method(CLQFM)was used to process the data.Quantitative analysis of three active substances in TCM was conducted.A fivewavelength fusion fingerprint(FWFF)was developed,using second-order derivatives of UV spectral data to differentiate sample levels effectively.The combination of HPLC and UV spectrophotometry,along with electrochemical fingerprinting(ECFP),successfully evaluated total active substances.Ultimately,a multidimensional profiling analytical system for TCM was developed. 展开更多
关键词 TCM antiviral mixture five-wavelength fusion fingerprint(FWFF) Comprehensive Linear Quantification fingerprint Method(CLQFM) quantization fingerprint antioxidant activity profilling
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PEI-Ru@SiO_(2)-Au@Pt复合材料的制备与电化学发光性能
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作者 程高兴 王春 李桂新 《当代化工》 CAS 2024年第5期1026-1030,1105,共6页
采用化学氧化法合成了聚乙烯亚胺-联吡啶钌@二氧化硅-金@铂(PEI-Ru@SiO_(2)-Au@Pt)发光功能化纳米复合材料;构建灵敏稳定的响应界面,制备了精准高效的固相增强型电化学发光纳米复合材料。通过透射电子显微镜(TEM)、紫外-可见吸收光谱(UV... 采用化学氧化法合成了聚乙烯亚胺-联吡啶钌@二氧化硅-金@铂(PEI-Ru@SiO_(2)-Au@Pt)发光功能化纳米复合材料;构建灵敏稳定的响应界面,制备了精准高效的固相增强型电化学发光纳米复合材料。通过透射电子显微镜(TEM)、紫外-可见吸收光谱(UV-Vis)、傅里叶变换红外光谱(FTIR)、电化学阻抗谱(EIS)、循环伏安法(CV)和双电位阶跃法对合成的纳米复合材料进行了表征和性能测试。研究了PEI-Ru@SiO_(2)-Au@Pt纳米复合材料的形貌和结构以及电化学发光性能(ECL)。结果表明:PEI-Ru@SiO_(2)-Au@Pt纳米复合材料具有优异ECL性能,加入Au@Pt后,PEI-Ru@SiO_(2)-Au@Pt纳米复合材料的ECL强度是PEI-Ru@SiO_(2)的5倍。 展开更多
关键词 电化学发光 发光功能复合材料 金核铂壳 聚乙烯亚胺-联吡啶钌@二氧化硅
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Study on HPLC-DAD Fingerprint of Xueshuan Xinmaining Capsules
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作者 Chuang ZHAO Yuling LIU +3 位作者 Longfei LIN Chunmin WANG Hui LI Yujie YANG 《Medicinal Plant》 2024年第5期31-34,49,共5页
[Objectives]To establish the HPLC-DAD fingerprint of Xueshuan Xinmaining Capsule(XXC).[Methods]The chromatographic conditions for the analysis of XXC solution were as follows:XSelect HSS T3 column;acetonitrile-0.1%pho... [Objectives]To establish the HPLC-DAD fingerprint of Xueshuan Xinmaining Capsule(XXC).[Methods]The chromatographic conditions for the analysis of XXC solution were as follows:XSelect HSS T3 column;acetonitrile-0.1%phosphoric acid water was used as mo-bile phase,gradient elution;flow rate:1.0 mL/min;column temperature 30℃;The injection volume is 10μL.The quality of XXC samples produced by different manufacturers was evaluated by similarity evaluation and cluster analysis.[Results]In theHPLC-dad fingerprints of 15 batches of XXC,23 common peaks were identified and 9 peaks were identified,and the similarity was greater than 0.95.According to the re-sults of cluster analysis,15 batches of XXC samples could be divided into two categories,S2,S5,S6,S7 and S8 batches belonged to category Ⅰ,and the rest batches belonged to category Ⅱ.[Conclusions]In this study,a representative and universal identification method of Xxc HPLC-DAD fingerprint was established.The method has high precision,stability and repeatability,is simple and reliable,and provides a pow-erful reference for further improving the quality evaluation system of XXC. 展开更多
关键词 Xueshuan Xinmaining Capsule(XXC) HPLC-DAD fingerprint Identification of chemical component Quality evaluation
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微@介孔复合分子筛的合成及其加氢裂化性能
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作者 于政敏 《精细石油化工》 CAS 2024年第4期32-37,共6页
研究了微@介孔复合分子筛合成过程中TEOS水解状态、酸种类、核分子筛种类及性质等因素对合成产物性质的影响。结果表明,在适宜酸浓度下搅拌6h静置24h时TEOS可最大程度水解成活性Si物种,在核分子筛表面形成有序介孔壳层。合成过程中酸根... 研究了微@介孔复合分子筛合成过程中TEOS水解状态、酸种类、核分子筛种类及性质等因素对合成产物性质的影响。结果表明,在适宜酸浓度下搅拌6h静置24h时TEOS可最大程度水解成活性Si物种,在核分子筛表面形成有序介孔壳层。合成过程中酸根阴离子作用不同,Cl^(-)有助于复合分子筛比表面积的增加,C_(2)O_(4)^(2-)和NO_(3)^(-)有利于孔体积的增大。Y分子筛或Beta分子筛为核时,核分子筛自身酸量高、酸性强时有助于壳层介孔结构的生成及核壳结构的完整。以十二烷和甲苯为模型化合物,与含单一的Y或Beta分子筛催化剂相比,含复合分子筛催化剂具有更好的中间馏分油选择性,并且催化剂的加氢性能与酸性质、孔结构匹配越好,对甲苯的转化能力越强。 展开更多
关键词 @介孔 核壳结构 复合分子筛 加氢裂化
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