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Microblog Burst Keywords Detection Based on Social Trust and Dynamics Model

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Chinese Journal of Electronics 2014年第4期23卷 695-700页

作者： DONG Guozhong LI Ruiguang YANG Wu WANG Wei GONG Liangyi SHEN Guowei YU Miao LV Jiguang Information Security Research Center Harbin Engineering University national Computer network Emergency Response Technical Team/Coordination Center

Microblog has emerged as a popular medium for providing new sources of information and rapid communications, particularly during burst topics. Burst keywords detection from real-time microblog streams is important for burst topics detection. The exiting algorithms may detect fake burst keywords without taking into account the trustworthiness of the users and human’s daily timetable. Our work is the first to combine the trustworthiness of the users with burst keywords detection. We propose a novel approach to detect burst keywords based on social trust and dynamics model. We adapt basic notions of dynamics from physics and model keywords bursts as momentum change of the keywords. On the analogy of physical dynamics model, this approach defines mass as the trustworthiness of user and position as the frequency of keywords. We compute each keyword’s burst value by using Moving average convergence/divergence(MACD) and determine whether it is a burst keyword in a given time window. The experimental results on large-scale Sina microblog dataset show that the proposed approach can avoid detecting fake burst keywords.

关键词： Sina microblog Burst keywords detection Social trust Dynamics model

Deterministic quantum communication using the symmetric W state

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Science China(Physics,Mechanics & Astronomy) 2013年第10期56卷 1903-1908页

作者： TSAI Chia-Wei HWANG Tzonelih Smart network System Institute at Institute for Information Industry Department of Computer Science and Information Engineering National Cheng Kung University

This study proposes a new coding function for the symmetric W state. Based on the new coding function, a theoretical protocol of deterministic quanama communication （DQC） is proposed. The sender can use the proposed coding function to encode his/her message, and the receiver can perform the imperfect Bell measurement to obtain the sender＇s message. In comparison to the existing DQC protocols that also use the W class state, the proposed protocol is more efficient and also more practical within today＇s technology. Moreover, the security of this protocol is analyzed to show that any eavesdropper will be detected with a very high probability under both the ideal and the noisy quantum channel.

关键词： deterministic quantum communication symmetric W state imperfect Bell measurement

Spectral analysis of the UFBG-based acousto optical modulator in V–I transmission matrix formalism

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Chinese Physics B 2014年第11期23卷 251-256页

作者：吴良英裴丽刘超王一群翁思俊王建帅 Key Laboratory of All Optical network & Advanced Telecommunication network of EMC Beijing Jiaotong Univcnersity

In this study, the V –I transmission matrix formalism(V –I method) is proposed to analyze the spectrum characteristics of the uniform fiber Bragg grating(FBG)-based acousto–optic modulators(UFBG-AOM). The simulation results demonstrate that both the amplitude of the acoustically induced strain and the frequency of the acoustic wave(AW) have an effect on the spectrum. Additionally, the wavelength spacing between the primary reflectivity peak and the secondary reflectivity peak is proportional to the acoustic frequency with the ratio 0.1425 nm/MHz. Meanwhile, we compare the amount of calculation. For the FBG whose period is M, the calculation of the V –I method is 4 ×(2M-1) in addition/subtraction,8 ×(2M- 1) in multiply/division and 2M in exponent arithmetic, which is almost a quarter of the multi-film method and transfer matrix(TM) method. The detailed analysis indicates that, compared with the conventional multi-film method and transfer matrix(TM) method, the V –I method is faster and less complex.

关键词： uniform fiber bragg grating(UFBG) acousto–optic modulator(AOM) V–I transmission matrix formalism spectrum

A Study on Influential User Identification in Online Social networks

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Chinese Journal of Electronics 2016年第3期25卷 467-473页

作者： WANG Nan SUN Qindong ZHOU Yadong SHEN Si Shaanxi Key Laboratory of network Computing and Security Xi'an University of Technology Ministry of Education Key Laboratory For Intelligent network and network Security Xi'an Jiaotong University

Influential user evaluation is great importance in many application areas of online social *** order to identify influential users in a more adequate and practical way, we propose a Dynamic regional interaction model(DRI) to evaluate user influence in online social networks. Influential users can be identified by the influence effect on different distance users based on dynamic regional interaction model. We have applied the influential user identification method to Sina Weibo and the experimental results show that compared with the existing methods the proposed method can identify the influence users in a more accuracy and efficiency way.

关键词： Online social networks Influential user identification Dynamic regional interaction model(DRI) User influence evaluation

The Full-Duplex Artificial Noise Scheme for Security of a Cellular System

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China Communications 2015年第S1期12卷 150-156页

作者： JI Xinsheng KANG Xiaolei HUANG Kaizhi LI Na YI Ming China national Digital Switching System Engineering & Technological R&D Center national Mobile Communications Research Laboratory Southeast University Wireless Technology Innovation Institute National Engineering Laboratory for Mobile Network Security

This paper focuses on the problem of secure transmission in a cellular system. A full-duplex base station using artificial noise is adopted to improve both the uplink and downlink secrecy rate via pairing terminals which reverses the downlink and uplink of each other. We give the designs of artificial noise and the user's desired signal, and derive the pairing prin-ciple between terminals. Moreover, the influence of self-interference cancellation on secrecy rate is ex-plored. Simulation results show that the secrecy rate can get much better performance by adopting full-duplex artificial noise scheme and proposed pair-ing method. The downlink secrecy rate decreases with the distance between terminals. Besides the uplink secrecy rate is sensitive to the ability of self-interference cancellation.

关键词： physical layer security cellular system full duplex artificial noise

Modeling and Performance Analysis of UAV-Aided Millimeter Wave Cellular networks with Stochastic Geometry

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China Communications 2024年第6期21卷 146-162页

作者： Li Junruo Wang Yuanjie Cui Qimei Hou Yanzhao Tao Xiaofeng national Engineering Laboratory for Mobile network Technologies Beijing University of Posts and TelecommunicationsBeijing 100876China national Computer network Emergency Response Technical Team/Coordination Center of China(CNCERT/CC) Beijing 100029China Department of Broadband Communication Peng Cheng LaboratoryShenzhen 518055China

UAV-aided cellular networks,millimeter wave(mm-wave) communications and multi-antenna techniques are viewed as promising components of the solution for beyond-5G(B5G) and even 6G *** leveraging the power of stochastic geometry,this paper aims at providing an effective framework for modeling and analyzing a UAV-aided heterogeneous cellular network,where the terrestrial base stations(TBSs) and the UAV base stations(UBSs) coexist,and the UBSs are provided with mm-wave and multi-antenna *** modeling the TBSs as a PPP and the UBSs as a Matern hard-core point process of type Ⅱ(MPH-Ⅱ),approximated but accurate analytical results for the average rate of the typical user of both tiers are derived through an approximation method based on the mean interference-to-signal ratio(MISR) *** influence of some relevant parameters is discussed in detail,and some insights into the network deployment and optimization are *** results show that some trade-offs are worthy of being considered,such as the antenna array size,the altitude of the UAVs and the power control factor of the UBSs.

关键词： average rate downlink millimeter wave point process theory SIR stochastic geometry UAVaided cellular networks

Low-complexity multiplexer-based normal basis multiplier over GF（2^m）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第6期10卷 834-842页

作者： Jenn-Shyong HORNG I-Chang JOU Chiou-Yng LEE Institute of Engineering Science and Technology National Kaohsiung First University of Science and Technology Department of Computer Information and network Engineering Lunghwa University of Science and Technology

We present a new normal basis multiplication scheme using a multiplexer-based algorithm. In this algorithm, the proposed multiplier processes in parallel and has a multiplexer-based structure that uses MUX and XOR gates instead of AND and XOR gates. We show that our multiplier for type-1 and type-2 normal bases saves about 8% and 16%, respectively, in space complexity as compared to existing normal basis multipliers. Finally, the proposed architecture has regular and modular con-figurations and is well suited to VLSI implementations.

关键词： Finite field multiplication Normal basis Gaussian normal basis Elliptic curve cryptosystem

Energy-aware deployment of dense heterogeneous cellular networks with QoS constraints

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Science China(Information Sciences) 2017年第4期60卷 148-165页

作者： Qimei CUI Zhiyan CUI Wei ZHENG Riku JNTTI Weiliang XIE national Engineering Laboratory for Mobile network Security Beijing University of Posts and Telecommunications Department of Communications and networking Aalto University China Telecom Corporation Limited

The base station(BS) configuration is a key factor to improve energy efficiency(EE). In this paper,we focus on designing the network deployment parameters(i.e., BS densities) for biased K-tier heterogeneous cellular network(HCN) with quality of service(Qo S) provisioning. Using appropriate approximations, we derive the closed-form expressions of optimal BS density across all tiers to minimize the area power consumption(APC) by applying the stochastic geometry theory, while satisfying the users’ Qo S requirements. These results are used to obtain some new insights into the EE performance of biased HCN deployment. With the aid of this approach, the best type of BSs to be deployed or switched off for energy saving purposes can be identified from the perspectives of BS transmission power. More precisely, if the BS transmission power ratio between an arbitrary pair of tiers of K-tier HCN, e.g., the small cell BS and macro BS tiers, is higher than a threshold which is a function of path loss exponent, bias factor and power consumption, the small cell BSs are *** opposite situation takes place otherwise. Furthermore, it is also shown that, compared to the unbiased HCN scenario, significant energy savings are possible by appropriately biasing the HCN and optimizing the BS density, subject to the Qo S constraints among all tiers.

关键词： heterogeneous cellular networks stochastic geometry energy efficiency BS density energy saving

Intelligent Covert Communication Design for Cooperative Cognitive Radio network

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China Communications 2023年第7期20卷 122-136页

作者： Zan Li Jia Shi Chao Wang Danyang Wang Xiaomeng Li Xiaomin Liao The national Key Laboratory of Space-Air-Ground Integrated Service network Xidian UniversityXi’an 710071China School of Information and Communications National University of Defense TechnologyWuhan 430035China

Extensive research attentions have been devoted to studying cooperative cognitive radio networks(CCRNs),where secondary users(SU)providing cooperative transmissions can be permitted by primary users(PU)to use *** order to maximize SU’s utility,SU may transmit its own information during the period of cooperative transmission,which stimulates the use of covert transmission against PU’s *** this sake,this article reviews the motivations of studying covert communications in *** particular,three intelligent covert transmission approaches are developed for maximizing SU’s utility in CCRNs,namely,intelligent parasitic covert transmission(IPCT),intelligent jammer aided covert transmission(IJCT)and intelligent reflecting surface assisted covert transmission(IRSC).Further,some raw performance evaluations are discussed,and a range of potential research directions are also provided.

关键词： cognitive radio networks covert transmis-sion machine learning