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Magic Mark: a marking menu using 2D direction and 3D depth information

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Science China(Information Sciences) 2018年第6期61卷 238-240页

作者： Fei LYU Rui XI Yuxin HAN Yujie LIU School of Digital Media and Design Arts Beijing University of Posts and Telecommunications Beijing Key Laboratory of network systems and network Culture Beijing University of Posts and Telecommunications

Menus are important interactive components of user interfaces,broadly applied to command exploration and selection[1].For large displays,RapMenu and touchless circular menus explored the design space of tilt and 2D direction[2,3].However,as one of the important input modalities,3D depth information has not been fully utilized for menu control in large displays.

关键词： Magic Mark Figure

3D tomographic analysis of equatorial plasma bubble using GNSS-TEC data from Indonesian GNSS network

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Earth and Planetary Physics 2025年第1期9卷 127-136页

作者： Ihsan Naufal Muafiry Prayitno Abadi Teguh N.Pratama Dyah R.Martiningrum Sri Ekawati Yuandhika GWismaya Febrylian FChabibi Gatot HPramono Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia dept.of Physics Faculty of ScienceUniversiti Teknologi MalaysiaJohor BahruMalaysia dept.Earth Planet Sci. Hokkaido UniversitySapporoJapan School of Electrical Engineering Telkom UniversityBandungIndonesia

Equatorial Plasma Bubbles(EPBs)are ionospheric irregularities that take place near the magnetic *** most commonly occur after sunset during the equinox months,although they can also be observed during other *** phenomenon significantly disrupts radio wave signals essential to communication and navigation *** national network of Global Navigation Satellite System(GNSS)receivers in Indonesia(>30°longitudinal range)provides an opportunity for detailed EPB *** explore this,we conducted preliminary 3D tomography of total electron content(TEC)data captured by GNSS receivers following a geomagnetic storm on December 3,2023,when at least four EPB clusters occurred in the Southeast Asian *** and extracted TEC depletion with a 120-minute running average were then used as inputs for a 3D tomography *** 2D spatial distribution consistently captured the four EPB clusters over *** tomography results were validated through a classical checkerboard test and comparisons with other ionospheric data sources,such as the Global Ionospheric Map(GIM)and International Reference Ionosphere(IRI)*** of the results demonstrates the capability of the Indonesian GNSS network to measure peak ionospheric *** findings highlight the potential for future three-dimensional research of plasma bubbles in low-latitude regions using existing GNSS networks,with extensive longitudinal coverage.

关键词： EPB Indonesian GNSS network 3D tomography

Quality of experience evaluation of HTTP video streaming based on user interactive behaviors

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The Journal of China Universities of Posts and telecommunications 2017年第3期24卷 24-32页

作者： Li Wenjing Yu Peng Wang Ruiyi Feng Lei Dong Ouzhou Qiu Xuesong Institute of network Technology Beijing University of Posts and Telecommunications

User interactive behaviors play a dual role during the hypertext transfer protocol （HTTP） video service： reflection and influence. However, they are seldom taken into account in practices. To this end, this paper puts forward the user interactive behaviors, as subjective factors of quality of experience （QoE） from viewer level, to structure a comprehensive multilayer evaluation model based on classic network quality of service （QoS） and application QoS. First, dual roles of user behaviors are studied and the characteristics are extracted where the user experience is correlated with user interactive behaviors. Furthermore, we categorize QoE factors into three dimensions and build the metric system. Then we perform the subjective tests and investigate the relationships among network path quality, user behaviors, and QoE. Ultimately, we employ the back propagation neural network （BPNN） to validate our analysis and model. Through the simulation experiment of mathematical and BPNN, the dual effects of user interaction behaviors on the reflection and influence of QoE in the video stream are analyzed, and the QoE metric system and evaluation model are established.

关键词： HTTP video streaming QoE user interactive behaviors BPNN

Analyzing the dynamics of online video popularity

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The Journal of China Universities of Posts and telecommunications 2017年第3期24卷 58-69页

作者： Ouyang Shuxin Li Chenyu Li Xueming School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of network System and network Culture Beijing University of Posts and Telecommunications

Given the large volume of video content and the diversity of user attention, it is of great importance to understand the characteristics of online video popularity for technological, economic and social reasons. In this paper, based on the data collected from a leading online video service provider in China, namely Youku, the dynamics of online video popularity are analyzed in-depth from four key aspects： overall popularity distribution, individual popularity distribution, popularity evolution pattern and early-future popularity relationship. How the popularity of a set of newly upload videos distributes throughout the observation period is first studied. Then the notion popularity distributions of individual videos are carefully studied. of active days is proposed, and the per-day and per-hour Next, how the popularity of an individual video evolves over time is investigated. The evolution patterns are further defined according to the number and temporal locations of popularity bursts, in order to describe the popularity growth trend. At last, the linear relationship between early video popularity and future video popularity are examined on a log-log scale. The relationship is found to be largely impacted by the popularity evolution patterns. Therefore, the specialized models are proposed to describe the correlation according to the popularity evolution patterns. Experiment results show that specialized models can better fit the correlation than a general model. Above all, the analysis results in our work can provide direct help in practical for the interested parties of online video service such as service providers, online advisers, and network operators.

关键词： online video service online content popularity popularity evolution pattern early-future popularity relationship

Progressive framework for deep neural networks: from linear to non-linear

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The Journal of China Universities of Posts and telecommunications 2016年第6期23卷 1-7页

作者： Shao Jie Zhao Zhicheng Su Fei Cai Anni School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of network System and network Culture Beijing University of Posts and Telecommunications

We propose a novel progressive framework to optimize deep neural networks. The idea is to try to combine the stability of linear methods and the ability of learning complex and abstract internal representations of deep leaming methods. We insert a linear loss layer between the input layer and the first hidden non-linear layer of a traditional deep model. The loss objective for optimization is a weighted sum of linear loss of the added new layer and non-linear loss of the last output layer. We modify the model structure of deep canonical correlation analysis （DCCA）, i.e., adding a third semantic view to regularize text and image pairs and embedding the structure into our framework, for cross-modal retrieval tasks such as text-to-image search and image-to-text search. The experimental results show the performance of the modified model is better than similar state-of-art approaches on a dataset of National University of Singapore （NUS-WIDE）. To validate the generalization ability of our framework, we apply our framework to RankNet, a ranking model optimized by stochastic gradient descent. Our method outperforms RankNet and converges more quickly, which indicates our progressive framework could provide a better and faster solution for deep neural networks.

关键词： framework neural network DCCA semantic RankNet

Physical layer authentication in UAV-enabled relay networks based on manifold learning

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Science China(Information Sciences) 2022年第12期65卷 263-283页

作者： Shida XIA Xiaofeng TAO Na LI Shiji WANG Jin XU National Engineering Lab for Mobile network Technologies Beijing University of Posts and Telecommunications Beijing University of Posts and telecommunications Research Institute

An unmanned aerial vehicle(UAV) relay network is a promising solution in the next-generation wireless networks due to its high capacity and unlimited geography. However, because of the openness of wireless channels and UAV mobility, it is remarkably challenging to guarantee the secure access of UAV relay. In this paper, we investigate the physical layer authentication(PLA) to verify the identity of the UAV relay for preventing unauthorized access to users’ information or network service. Unlike most existing PLA methods for UAV, the proposed PLA scheme fully considers the time-varying of physical layer attributes caused by UAV mobility, and transforms the authentication problem into recognizing nonlinearly separable physical layer data. Particularly, we propose a manifold learning-based PLA scheme that can authenticate the mobile UAV relay in real time by establishing the local correlation of physical layer attributes. The Markov chain of physical layer data in the time domain is established to evaluate UAV state transition probability through the proposed diffusion map algorithm. The legitimate UAV and spoofing attackers can always be authenticated by the different motion states. Performance analysis offered a comprehensive understanding of the proposed scheme. Extensive simulations confirm that the performance of the proposed scheme improves over 18% in resisting the intelligent spoofing UAV compared with the traditional methods.

关键词： UAV relay physical layer authentication mobility manifold learning diffusion map state transition probability

Consensus in nonlinear multi-agent systems with nonidentical nodes and sampled-data control

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Science China(Information Sciences) 2018年第12期61卷 141-154页

作者： Zhengxin WANG Jingbo FAN Guo-Ping JIANG Jinde CAO Min XIAO Ahmed ALSAEDI School of Science Nanjing University of Posts and Telecommunications School of Automation Nanjing University of Posts and Telecommunications Department of Mathematics Faculty of Science King Abdulaziz University Research Center for Complex systems and network Sciences School of MathematicsSoutheast University

This paper primarily discusses the leader-following consensus problem in nonlinear second-order multi-agent systems with nonidentical nodes. Sampled-data-based protocols are applied to reach *** delay-free and input-delay protocols are proposed. Based on the Lyapunov functional approach and linear matrix inequality(LMI) method, sufficient criteria are obtained to guarantee quasi-consensus for nonlinear heterogeneous multi-agent systems. All the heterogeneous followers can track the leader within a bounded range. Furthermore, the error systems between the leader and each follower eventually converge to a convergence domain that depends on the heterogeneity among the dynamics of the agents. Additionally,leader-following consensus can also be reached as the heterogeneity vanishes. Finally, numerical simulations are provided to illustrate the theoretical results.

关键词： heterogeneous systems multi-agent systems quasi-consensus leader-following consensus sampled-data control

Secret key generation over a Nakagami-m fading channel with correlated eavesdropping channel

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Science China(Information Sciences) 2022年第9期65卷 273-285页

作者： Shixun GONG Xiaofeng TAO Na LI Haowei WANG Jin XU National Engineering Laboratory for Mobile network Technologies Beijing University of Posts and Telecommunications Beijing University of Posts and telecommunications Research Institute

The analysis of secret key capacity is an important investigation on the design of secret key agreement protocol. In this paper, we characterize the secret key capacity based on received signal envelopes obeying Nakagami-m distribution between two legitimate users, in the presence of a passive eavesdropper,when the eavesdropping channel is correlated with the legitimate channel. The expression of secret key capacity is derived based on mutual information and applies to both integer and non-integer m. Simulation results indicate that the secret key capacity is proportional to m-fading parameter and average signal-tonoise ratio(SNR) and inversely proportional to the number of paths. In addition, some behaviors of secret key capacity over a high mobility fading channel, and microcell and macrocell environments are *** results cover the performance of secret key capacity when the received signal envelope follows Rayleigh,Rician, and Gaussian distributions.

关键词： physical layer security physical layer secret key generation Nakagami-m fading correlated eavesdropping channel secret key capacity

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Differential game-based analysis of multi-attacker multi-defender interaction

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Science China(Information Sciences) 2021年第12期64卷 202-214页

作者： Qiuyue GAO Huici WU Yunfei ZHANG Xiaofeng TAO National Engineering Laboratory for Mobile network Technologies Beijing University of Posts and Telecommunications

Due to the increasing number of wireless terminals and progressively extensive interconnections among them, interaction between the attack group and defense group is becoming a dominant security manifestation in future wireless networks. This paper focuses on the modeling and analysis of multi-attacker to multi-defender interaction. First, considering the continuous interaction between the attack group and defense group in real-time, a differential game-based multi-attacker to multi-defender interaction model is explicated with paralysis threshold introduced to reduce the ping-pong effect in paralysis. Optimal control theory is then introduced to obtain the equilibrium strategy with Hamilton best control method and a proposed optimal strategy selection algorithm for multi-attacker to multi-defender interaction. Finally, simulations are provided to demonstrate the evolutionary trajectory of optimal attack and defensive strategies and the relationship between the paralysis threshold and the group strength evolution results. Numerical results show the attackers and defenders are aggressive to strengthen their groups initially and then gradually decrease their strength to obtain ideal cost-effectiveness ratios. Moreover, increasing the defense paralysis threshold within a certain range will be more conducive to improving the defense effectiveness.

关键词： differential game multi-attacker to multi-defender interaction optimal control theory Hamilton function equilibrium strategy