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SGNR: A Social Graph Neural Network Based Interactive Recommendation Scheme for E-Commerce

清华大学学报:自然科学版(英文版) 2023年第4期28卷 786-798页

作者： Dehua Ma Yufeng Wang Jianhua Ma Qun Jin school of Communications and lnformation Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Department the Faculty of Computer and Information SciencesHosei UniversityTokyo 194-0298Japan Networked Information systems Laboratory Department of Human Informatics and Cognitive SciencesFaculty of Human SciencesWaseda UniversityTokyo 169-8050Japan

Interactive Recommendation(IR)formulates the recommendation as a multi-step decision-making process which can actively utilize the individuals’feedback in multiple steps and optimize the long-term user benefit of *** Reinforcement Learning(DRL)has witnessed great application in IR for ***,user cold-start problem impairs the learning process of the DRL-based recommendation ***,most existing DRL-based recommendations ignore user relationships or only consider the single-hop social relationships,which cannot fully utilize the social *** fact that those schemes can not capture the multiple-hop social relationships among users in IR will result in a sub-optimal *** address the above issues,this paper proposes a Social Graph Neural network-based interactive Recommendation scheme(SGNR),which is a multiple-hop social relationships enhanced DRL *** this framework,the multiple-hop social relationships among users are extracted from the social network via the graph neural network which can sufficiently take advantage of the social network to provide more personalized recommendations and effectively alleviate the user cold-start *** experimental results on two real-world datasets demonstrate that the proposed SGNR outperforms other state-of-the-art DRL-based methods that fail to consider social relationships or only consider single-hop social relationships.

关键词： Interactive Recommendation(IR) Deep Reinforcement Learning(DRL) Graph Neural Network(GNN)

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A subband excitation substitute based scheme for narrowband speech watermarking

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 627-643页

作者： Wei LIU Ai-qun HU school of lnformation Science and Engineering Southeast UniversityNanjing 210096China

We propose a new narrowband speech watermarking scheme by replacing part of the speech with a scaled and spectrally shaped hidden signal. Theoretically, it is proved that if a small amount of host speech is modified, then not only an ideal channel model for hidden communication can be established, but also high imperceptibility and good intelligibility can be achieved. Furthermore, a practical system implementation is proposed. At the embedder, the power normalization criterion is first imposed on a passband watermark signal by forcing its power level to be the same as the original passband excitation of the cover speech, and a synthesis filter is then used to spectrally shape the scaled watermark signal. At the extractor, a bandpass filter is first used to get rid of the out-of-band signal, and an analysis filter is then employed to compensate for the distortion introduced by the synthesis filter. Experimental results show that the data rate is as high as 400 bits/s with better bandwidth efficiency, and good imperceptibility is achieved. Moreover, this method is robust against various attacks existing in real applications.

关键词： Analysis filter Linear prediction Narrowband speech watermarking Passband excitation replacement Power normalization Spectral envelope shaping Synthesis filter

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Study on Multiplexing Ability of Identical Fiber Bragg Gratings in a Single Fiber

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Chinese Journal of Aeronautics 2011年第5期24卷 607-612页

作者： LIU Jiansheng ZHANG Jing LI Xin ZHENG Zheng school of Electronics and lnformation Engineering Beihang University Beijing 100191 China

The multiplexing ability of a novel multiplexing fiber Bragg grating （FBG） method based on Optical Time Domain Reflecto meter （OTDR） and Time Division Multiplexing TDM technologies has been theoretically analyzed and studied. This method permits the interrogation of hundreds of identical FBGs with low reflectivity in a single fiber, making the FBG sensors more applicable in the aerospace health monitoring engineering. The analysis shows that the multiplexing ability can be greatly improved if the FBG reflectivity is sufficiently low. And hence, an inexpensive large-scale distributed sensing system based on this method can be realized, When evaluating the multiplexing ability of this system, we propose for the first time that the interference effect of multi-reflections among FBGs should be taken into consideration.

关键词： Bragg gratings multiplexing low reflectivity multi-reflection interference effect

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Ground Moving Target Tracking with VS-IMM Using Mean Shift Unscented Particle Filter

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Chinese Journal of Aeronautics 2011年第5期24卷 622-630页

作者： GAO Caicai CHEN Wei school of Electronics and lnformation Engineering Beihang University Beijing 100191 China

In order to track ground moving target, a variable structure interacting multiple model （VS-IMM） using mean shift unscented particle filter （MS-UPF） is proposed in this paper. In model-conditioned filtering, sample particles obtained from the unscented particle filter are moved towards the maximal posterior density estimation of the target state through mean shift. On the basis of stop model in VS-IMM, hide model is proposed. Once the target is obscured by terrain, the prediction at prior time is used instead of the measurement at posterior time; in addition, the road model set used is not changed. A ground moving target indication （GMTI） radar is employed in three common simulation scenarios of ground target： entering or leaving a road, crossing a junction and no measurement. Two evaluation indexes, root mean square error （RMSE） and average normalized estimation error squared （ANEES）, are used. The results indicate that when the road on which the target moving changes, the tracking accuracy is effectively improved in the proposed algorithm. Moreover, track interruption could be avoided if the target is moving too slowly or masked by terrain.

关键词： ground moving target tracking mean shift unscented particle filter hide model road information variable structure interacting multiple model

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Tunable ponderomotive squeezing induced by Coulomb interaction in an optomechanical system

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Chinese Physics B 2016年第1期25卷 446-451页

作者：吴琴 school of lnformation Engineering Guangdong Medical UniversityDongguan 523808China

We investigate the properties of the ponderomotive squeezing in an optomechanical system coupled to a charged nanomecbanical oscillator （NMO） nearby via Coulomb force. We find that the introduction of Coulomb interaction allows the generation of squeezed output light from this system. Our numerical results show that the degree of squeezing can be tuned by the Coulomb coupling strength, the power of laser, and the frequencies of NMOs. Furthermore, the squeezing generated in our approach can be used to measure the Coulomb coupling strength.

关键词： ponderomotive squeezing Coulomb interaction optomechanical system

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Up-conversion photoluminescence emissions of CaMoO4：Pr3＋/Yb3＋ powder

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Journal of Rare Earths 2017年第7期35卷 645-651页

作者：李金萍张婷婷朱刚强郑海荣 school of Physics and lnformation Technology Shaanxi Normal University Xi'an 710062 China

CaMoO_4：Pr^（3＋）/Yb^（3＋） powder was successfully synthesized by a facile hydrothermal method. X-ray diffraction（XRD） patterns of samples confirmed tetragonal structure and morphology and sizes were confirmed by scanning electron microscopy（SEM） analyses. Particles consisted of regular micro-spheres with uniform sizes, the diameter of each sphere lay in the range of 3 to 4 μm. The up-conversion photoluminescence emission and its concentration dependence were investigated under infrared excitation at 980 nm. All the UC micro-particles exhibited the typical blue, green and red emissions. Dominant blue emissions originated from ~3P_0→~3H_4 and intense red emissions originated from ~3P0→~3F_2 transitions, and they both belonged to two-photon excitation processes in CaMoO_4： Yb^（3＋）/Pr^（3＋） powder. The optimum doping concentrations of Pr^（3＋） and Yb^（3＋） for the highest UC luminescence were 0.1 mol.% and 16 mol.%, respectively. The possible up-conversion mechanisms were discussed in detail. It was found that the UC emission could be well controlled from blue to green to white color by adjusting the concentration of Pr^（3＋） ions in CaMoO_4：Pr^（3＋）/Yb^（3＋） microcrystal. So it is a candidate material for solid-state lasers, biological imaging, solar cells, and optical communications.

关键词： up-conversion luminescence rare earths optical properties hydrothermal method

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A Novel Onboard-gateway-based Mechanism to Improve TCP Performance in Aeronautical Satellite Networks

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Chinese Journal of Aeronautics 2007年第3期20卷 260-265页

作者： GU Ming ZHANG Jun school of Electronics and lnformation Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The IP-based networks on aircraft serve to support Intemet services via satellites. However, in aeronautical satellite hybrid networks, the TCP protocol performance often deteriorates due to improper decreases and slow recovery of the congestion window. This paper proposes a window size determination and notification mechanism, onboard-gateway-based mechanism （OGBM）, which is based on the onboard gateway in the networks on aircraft. A cross-layer approach is adopted by the onboard gateway to obtain the satellite link bandwidth information. And then, by the gateway, through changing the receiver＇s advertised window field in ACK packets, TCP sources are notified of the window size of each TCP source calculated on the ground of bandwidth delay product and flow numbers. The mechanism is able to avoid improper changes of TCP window and serve multiple users. Simulation results show that the mechanism with the fairness index close to l improves TCP performance in aeronautical satellite networks.

关键词： congestion control TCP gateway aeronautical satellite network

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Core-based Shared Tree Multicast Routing Algorithms for LEO Satellite IP Networks

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Chinese Journal of Aeronautics 2007年第4期20卷 353-361页

作者： Cheng Lianzhen Zhang Jun Liu Kai school of Electronics and lnformation Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

A new core-based shared tree algorithm, viz core-cluster combination-based shared tree （CCST） algorithm and the weighted version （i.e. w-CCST algorithm） are proposed in order to resolve the channel resources waste problem in typical source-based multicast routing algorithms in low earth orbit （LEO） satellite IP networks. The CCST algorithm includes the dynamic approximate center （DAC） core selection method and the core-cluster combination multicast route construction scheme. Without complicated onboard computation, the DAC method is uniquely developed for highly dynamic networks of periodical and regular movement. The core-cluster combination method takes core node as the initial core-cluster, and expands it stepwise to construct an entire multicast tree at the lowest tree cost by a shortest path scheme between the newly-generated core-cluster and surplus group members, which results in great bandwidth utilization. Moreover, the w-CCST algorithm is able to strike a balance between performance of tree cost and that of end-to-end propagation delay by adjusting the weighted factor to meet strict end-to-end delay requirements of some real-time multicast services at the expense of a slight increase in tree cost. Finally, performance comparison is conducted between the proposed algorithms and typical algorithms in LEO satellite IP networks. Simulation results show that the CCST algorithm significantly decreases the average tree cost against to the others, and also the average end-to-end propagation delay ofw-CCST algorithm is lower than that of the CCST algorithm.

关键词： satellite IP networks LEO multicast routing shared tree core

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Explosion limits for combustible gases

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Mining Science and Technology 2009年第2期19卷 182-184页

作者： TONG Min-ming WU Guo-qing HAO Ji-fei DAI Xin-lian school of lnformation and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Combustible gases in coal mines are composed of methane,hydrogen,some multi-carbon alkane gases and other *** on a numerical calculation,the explosion limits of combustible gases were studied,showing that these limits are related to the concentrations of different components in the *** an increase of C4H10 and C6H14,the Lower ExplosionLimit(LEL) and Upper Explosion-Limit(UEL) of a combustible gas mixture will decrease *** every 0.1% increase in C4H10 and C6H14,the LEL decreases by about 0.19% and the UEL by about 0.3%.The results also prove that,by increasing the amount of H2,the UEL of a combustible gas mixture will increase *** the level of H2 increases by 0.1%,the UEL will increase by about 0.3%.However,H2 has only a small effect on the LEL of the combustible gas *** study provides a theoretical foundation for judging the explosion risk of an explosive gas mixture in mines.

关键词：可燃气体爆炸极限气体混合物可燃混合气数值计算组成部分爆炸危险测量

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Hash-based signature revisited

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Cybersecurity 2022年第4期5卷 71-96页

作者： Lingyun Li Xianhui Lu Kunpeng Wang State Key Laboratory of Information Security Institute of lnformation EngineeringCASNo.89 Minzhuang RoadHaidian DistrictBeijing 100093China school of Cyber Security University of Chinese Academy of SciencesNo.19 Yuquan RoadShijingshan DistrictBeijing 100049China school of Computer Science Liaocheng UniversityNo.1Hunan RoadDongchangfu DistrictLiaochengCity 252000China.

The current development toward quantum attack has shocked our confidence on classical digital signature *** one of the mainstreams of post quantum cryptography primitives,hash-based signature has attracted more and more concern in both cryptographic research and application in recent *** goal of this paper is to present,classify and discuss different solutions for hash-based ***,this paper discusses the research progress in the component of hash-based signature,i.e.,one-time signature and few-time signature;then classifies the tree-based public key authentication schemes of hash-based signature into limited number and stateful schemes,unlimited number and stateful schemes and unlimited number and stateless *** above discussion aims to analyze the overall design idea of different categories of hash-based signatures,as well as the construction,security reduction and performance efficiency of specific ***,the perspectives and possible development directions of hash-based signature are briefly discussed.

关键词： Hash-based signature One-time signature Few-time signature Hash tree

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