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Deeply Understanding Graph-Based Sybil Detection Techniques via Empirical Analysis on Graph Processing

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China Communications 2020年第10期17卷 82-96页

作者： Jian Mao Xiang Li Qixiao Lin zhenyu guan Laboratory of Aerospace Network Security Ministry of Industry and Information TechnologySchool of Cyber Science and TechnologyBeihang UniversityBeijing 100191China Shanghai Key Laboratory of Integrated Administration Technologies for Information Security Shanghai 200240China Key Laboratory of Aerospace Network Security Ministry of Industry and Information TechnologyBeihang UniversityBeijing 100191China

Sybil attacks are one of the most prominent security problems of trust mechanisms in a distributed network with a large number of highly dynamic and heterogeneous devices,which expose serious threat to edge computing based distributed systems.Graphbased Sybil detection approaches extract social structures from target distributed systems,refine the graph via preprocessing methods and capture Sybil nodes based on the specific properties of the refined graph structure.Graph preprocessing is a critical component in such Sybil detection methods,and intuitively,the processing methods will affect the detection performance.Thoroughly understanding the dependency on the graph-processing methods is very important to develop and deploy Sybil detection approaches.In this paper,we design experiments and conduct systematic analysis on graph-based Sybil detection with respect to different graph preprocessing methods on selected network environments.The experiment results disclose the sensitivity caused by different graph transformations on accuracy and robustness of Sybil detection methods.

关键词： Sybil attack graph preprocessing Edge computing trust model

Dynamic data auditing scheme for big data storage

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Frontiers of Computer Science 2020年第1期14卷 219-229页

作者： Xingyue CHEN Tao SHANG Feng ZHANG Jianwei LIU zhenyu guan School of Electronic and Information Engineering Beihang UniversityBeijing 100083China School of Cyber Science and Technology Beihang UniversityBeijing 100083China

When users store data in big data platforms,the integrity of outsourced data is a major concern for data owners due to the lack of direct control over the data.However,the existing remote data auditing schemes for big data platforms are only applicable to static data.In order to verify the integrity of dynamic data in a Hadoop big data platform,we presents a dynamic auditing scheme meeting the special requirement of Hadoop.Concretely,a new data structure,namely Data Block Index Table,is designed to support dynamic data operations on HDFS(Hadoop distributed file system),including appending,inserting,deleting,and modifying.Then combined with the MapReduce framework,a dynamic auditing algorithm is designed to audit the data on HDFS concurrently.Analysis shows that the proposed scheme is secure enough to resist forge attack,replace attack and replay attack on big data platform.It is also efficient in both computation and communication.

关键词： big data data security remote data auditing dynamic update privacy protection

A Novel Objective Quality Assessment Method for Video Conferencing Coding

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China Communications 2019年第4期16卷 89-104页

作者： zhenyu guan Hanzheng Lv Yuan Ma Jingze Zhang School of Cyber Science and Technology BeiHang University School of Electronic and Information Engineering BeiHang University

Most recently, due to the demand of immersive communication, region-of-interest-based(ROI) high efficiency video coding(HEVC) approaches in conferencing scenarios have become increasingly important. However, there exists no objective metric, specially developed for efficiently evaluating the perceived visual quality of video conferencing coding. Therefore, this paper proposes a novel objective quality assessment method, namely Gaussian mixture model based peak signal-tonoise ratio(GMM-PSNR), for the perceptual video conferencing coding. First, eye tracking experiments, together with a real-time technique of face and facial feature extraction, are introduced. In the experiments, importance of background, face, and facial feature regions is identified, and it is then quantified based on eye fixation points over test videos. Next, assuming that the distribution of the eye fixation points obeys Gaussian mixture model, we utilize expectation-maximization(EM) algorithm to generate an importance weight map for each frame of video conferencing coding, in light of a new term eye fixation points/pixel(efp/p). According to the generated weight map, GMM-PSNR is developed for quality assessment by assigning different weights to the distortion of each pixel in the video frame. Finally, we utilize some experiments to investigate the correlation of the proposed GMM-PSNR and other conventional objective metrics with subjective quality metrics. The experimental results show the effectiveness of GMM-PSNR.

关键词： visual quality assessment perceptual conferencing video coding immersive communication

河北泥河湾盆地西白马营遗址1985-1986年出土的石制品

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人类学学报 2024年第1期43卷 55-66页

作者：周振宇王法岗关莹中国社会科学院考古研究所北京100710 河北省文物考古研究院石家庄050031 中国科学院古脊椎动物与古人类研究所脊椎动物演化与人类起源重点实验室北京100044

西白马营遗址位于泥河湾盆地中部,于1985年调查发现并进行了试掘;次年正式发掘并获取了石制品、骨制品、动物化石等丰富的文化遗物。铀系法测年遗址距今约1.8万年,推测为临时石器加工场所。石器技术属于中国北方的小型石片石器传统。新... 详细信息

西白马营遗址位于泥河湾盆地中部,于1985年调查发现并进行了试掘;次年正式发掘并获取了石制品、骨制品、动物化石等丰富的文化遗物。铀系法测年遗址距今约1.8万年,推测为临时石器加工场所。石器技术属于中国北方的小型石片石器传统。新的田野工作和测年数据表明,遗址属旧石器时代晚期早段。我们对1985年试掘及1986年正式发掘出土的石制品进行了类型划分及技术分析,并结合最新的年代测定结果,对遗址文化面貌及属性进行了重新厘定及研究成果重要性的讨论。

关键词：泥河湾盆地旧石器时代晚期西白马营遗址石制品技术

Physical Unclonable Functions for IoT Device Authentication

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Journal of Communications and Information Networks 2019年第4期4卷 44-54页

作者： zhenyu guan Hao Liu Yuyao Qin Beihang University Beijing 100191China

The Internet of things(IoT),as an extension of the Internet,has become a trend of network develop-ment nowadays.In order to protect the integrity and authenticity of the information in the IoT,an identity authentication protocol applied to the networked devices is designed in this paper,using the physical unclonable function(PUF)to extract the uniqueness and tamper resistance of the randomness in the manufacturing process of the physical device.We propose the protocol including the database,accessed devices,access devices and users in the specific network environment.Relying on the unique identification information generated by the PUF embedded in devices and passwords set by users,devices and users identities could be verified through zero-knowledge proofs.The performance analysis and the experiment at the end of this work show that our protocol provides users with a strong security guarantee for IoT devices.

关键词： IoT PUF identity authentication SRAM

Lightweight and Manageable Digital Evidence Preservation System on Bitcoin

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Journal of Computer Science & Technology 2018年第3期33卷 568-586页

作者： Mingming Wang Qianhong Wu Bo Qin Qin Wang Jianwei Liu zhenyu guan School of Electronic and Information Engineering Beihang University Beijing 100191 China School of Information Renmin University of China Beijing 100872 China

An effective and secure system used for evidence preservation is essential to possess the properties of anti- loss, anti-forgery, anti-tamper and perfect verifiability. Traditional architecture which relies on centralized cloud storage is depressingly beset by the security problems such as incomplete confidence and unreliable regulation. Moreover, an expensive, inefficient and incompatible design impedes the effort of evidence preservation. In contrast, the decentralized blockchain network is qualified as a perfect replacement for its secure anonymity, irrevocable commitment, and transparent traceability. Combining with subliminal channels in blockchain, we have weaved the transaction network with newly designed evidence audit network. In this paper, we have presented and implemented a lightweight digital evidence-preservation architecture which possesses the features of privacy-anonymity, audit-transparency, function-scalability and operation-lightweight. The anonymity is naturally formed from the cryptographic design, since the cipher evidence under encrypted cryptosystem and hash-based functions leakages nothing to the public. Covert channels are efficiently excavated to optimize the cost, connectivity and security of the framework, transforming the great computation power of Bitcoin network to the value of credit. The transparency used for audit, which relates to the proof of existence, comes from instant timestamps and irreversible hash functions in mature blockchain network. The scalability is represented by the evidence chain interacted with the original blockchain, and the extended chains on top of mainchain will cover the most of auditors in different institutions. And the lightweight, which is equal to low-cost, is derived from our fine-grained hierarchical services. At last, analyses of efficiency, security, and availability have shown the complete accomplishment of our system.

关键词： blockchain covert channel data auditing digital evidence

An attack-immune trusted architecture for supervisory aircraft hardware

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Chinese Journal of Aeronautics 2021年第11期34卷 169-181页

作者： Dongxu CHENG Chi ZHANG Jianwei LIU Dawei LI zhenyu guan Wei ZHAO Mai XU School of Cyber Science and Technology Beihang UniversityBeijing 100191China Beijing Electro-Mechanical Engineering Institute Beijing 100074China

With the wide application of electronic hardware in aircraft such as air-to-ground communication,satellite communication,positioning system and so on,aircraft hardware is facing great secure pressure.Focusing on the secure problem of aircraft hardware,this paper proposes a supervisory control architecture based on secure System-on-a-Chip(So C)system.The proposed architecture is attack-immune and trustworthy,which can support trusted escrow application and Dynamic Integrity Measurement(DIM)without interference.This architecture is characterized by a Trusted Monitoring System(TMS)hardware isolated from the Main Processor System(MPS),a secure access channel from TMS to the running memory of the MPS,and the channel is unidirectional.Based on this architecture,the DIM program running on TMS is used to measure and call the Lightweight Measurement Agent(LMA)program running on MPS.By this method,the Operating System(OS)kernel,key software and data of the MPS can be dynamically measured without disturbance,which makes it difficult for adversaries to attack through software.Besides,this architecture has been fully verified on FPGA prototype system.Compared with the existing systems,our architecture achieves higher security and is more efficient on DIM,which can fully supervise the running of application and aircraft hardware OS.

关键词： Aircraft hardware Dynamic integrity measurement Supervisory control System-on-a-Chip(SoC) Trusted computing

电子舌和气相色谱-离子迁移谱技术分析炖煮时间对松茸鸡汤风味的影响

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中国食品学报 2024年第1期24卷 336-348页

作者：李想邓静易宇文关雎唐英明张振宇张浩四川旅游学院预制菜产业学院成都610100 川菜人工智能重点实验室成都610100 四川旅游学院烹饪科学四川省高等学校重点实验室成都610100 四川旅游学院烹饪学院成都610100

以雅江鲜松茸为试验材料,采用电子舌和气相色谱-离子迁移谱技术,使用主成分、正交偏最小二乘法判别分析,结合相对气味活度值分析炖煮时间对松茸鸡汤风味的影响。结果表明:鲜松茸对鸡汤滋味贡献很大,电子舌鲜味强度值从2.1提高到8.0。采... 详细信息

以雅江鲜松茸为试验材料,采用电子舌和气相色谱-离子迁移谱技术,使用主成分、正交偏最小二乘法判别分析,结合相对气味活度值分析炖煮时间对松茸鸡汤风味的影响。结果表明:鲜松茸对鸡汤滋味贡献很大,电子舌鲜味强度值从2.1提高到8.0。采用GC-IMS方法共检出45种化合物,加入松茸后醛类含量从47.88%下降到21.13%,由ROAV值(128.08)确认3-甲基-1-丁醇是松茸鸡汤的关键化合物。其中,伞花烃、3-辛醇、正辛醇是松茸鸡汤的特征化合物,使松茸鸡汤呈现独特的汽油味、苔藓清香、坚果香味、蘑菇气味和金属气味。炖煮5 min后,鸡汤中松茸特征风味最明显,达到最佳食用效果。研究结果为雅江松茸鸡汤风味特征研究提供参考。

关键词：雅江松茸炖煮时间电子舌气相色谱-离子迁移谱风味特征滋味特征

A batch microfabrication of a self-cleaning,ultradurable electrochemical sensor employing a BDD film for the online monitoring of free chlorine in tap water

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Microsystems & Nanoengineering 2022年第2期8卷 85-96页

作者： Jiawen Yin Wanlei Gao Weijian Yu Yihua guan zhenyu Wang Qinghui Jin Faculty of Electrical Engineering and Computer Science Ningbo University315211 NingboP.R.China State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences200050 ShanghaiP.R.China

Free chlorine is one of the key water quality parameters in tap water.However,a free chlorine sensor with the characteristics of batch processing,durability,antibiofouling/antiorganic passivation and in situ monitoring of free chlorine in tap water continues to be a challenging issue.In this paper,a novel silicon-based electrochemical sensor for free chlorine that can self-clean and be mass produced via microfabrication technique/MEMS(Micro-Electro-Mechanical System)is proposed.A liquid-conjugated Ag/AgCI reference electrode is fabricated,and electrochemically stable BDD/Pt is employed as the working/counter electrode to verify the effectiveness of the as-fabricated sensor for free chlorine detection.The sensor demonstrates an acceptable limit of detection(0.056 mg/L)and desirable linearity(R^(2)=0.998).Particularly,at a potential of+2.5 V,hydroxyl radicals are generated on the BBD electrode by electrolyzing water,which then remove the organic matter attached to the surface of the sensor though an electrochemical digestion process.The performance of the fouled sensor recovers from 50.2 to 94.1%compared with the initial state after self-cleaning for 30 min.In addition,by employing the MEMS technique,favorable response consistency and high reproducibility(RSD<4.05%)are observed,offering the opportunity to mass produce the proposed sensor in the future.A desirable linear dependency between the pH,temperature,and flow rate and the detection of free chlorine is observed,ensuring the accuracy of the sensor with any hydrologic parameter.The interesting sensing and selfcleaning behavior of the as-proposed sensor indicate that this study of the mass production of free chlorine sensors by MEMS is successful in developing a competitive device for the online monitoring of free chlorine in tap water.

关键词： chlorine batch electrode