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Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma school of Computer science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-20M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

Neighborhood-following algorithms for linear programming

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science china Mathematics 2004年第6期47卷 812-820页

作者： Al Wenbaoschool of science, beijing university of posts and telecommunications, beijing 100876, china 1. school of science Beijing University of Posts and Telecommunications 100876 Beijing China

In this paper, we present neighborhood-following algorithms for linear programming. When the neighborhood is a wide neighborhood, our algorithms are wide neighborhood primal-dual interior point algorithms. If the neighborhood degenerates into the central path, our algorithms also degenerate into path-following algorithms. We prove that our algorithms maintain the O9√nL) -iteration complexity still, while the classical wide neighborhood primal-dual interior point algorithms have only the O(nL-iteration complexity. We also proved that the algorithms are quadratic convergence if the optimal vertex is nondegenerate. Finally, we show some computational results of our algorithms.

关键词： linear programming primal-dual interior point methods wide neighborhood methods quadratic convergence

STABILITY OF GENERALIZED JACKSON NETWORKS WITH INFINITE SUPPLY OF WORK

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Journal of Systems science & Complexity 2008年第2期21卷 283-295页

作者： Yongjiang GUO school of science Beijing University of Posts and Telecommunications Beijing 100876 China

A general Jackson network （GJN） with infinite supply of work is considered. By fluid limit model, the author finds that the Markov process describing the dynamics of the GJN with infinite supply of work is positive Harris recurrent if the corresponding fluid model is stable. Furthermore, the author proves that the fluid model is stable if the usual traffic condition holds.

关键词： Fluid limit model general Jackson network (GJN) infinite supply positive Harris recurrent stability.

TWO-AGENT PARETO OPTIMAL COOPERATIVE INVESTMENT IN INCOMPLETE MARKET:AN EQUIVALENT CHARACTERIZATION

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Journal of Systems science & Complexity 2011年第4期24卷 701-710页

作者： Qing ZHOU school of science Beijing University of Posts and Telecommunications Beijing 100876 China.

This paper studies the following cooperative investment game with two agents. At the start of the game, both the agents＇ capital are collected. The total capital are then invested according to a certain trading strategy. At a certain time To one agent quits the cooperation and they divide the wealth among themselves. During the remaining period [To, T], the other agent invests his/her capital following a possibly different trading strategy. By stochastic optimization method combined with the theory of Backward Stochastic Differential Equations （BSDEs, for short）, we give an equivalent characterization of the Pareto optimal cooperative strategies.

关键词： Backward stochastic differential equation cooperative investment incomplete market,Pareto optimum stochastic utility.

Analyzing the Switching Characteristics of a NOLM Demultiplexer with on Analytic and Numrical Methods

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Chinese Journal of Lasers 1999年第5期8卷 419-424页

作者： LIU XianbinG YE Peida(telecommunications Engineering school, beijing university of posts and telecommunications, beijing 100876 china) 北京邮电大学电信工程学院北京

The switching characteristics of a NOLM demultiplexer are investigated by using an analytic and numerical method. The results reveal that the switching characteristics of a NOLM demultiplexer depend on parameters such as the power coupling ratio of the coupler,the peak power of control pulses, the walk-off and the initial time delay between signal pulses and control pulses, etc. The efficiency of NOLM is dependent on the peak power of controlpulses However, the switching window profile begins to oscillate as the power exceeds a critica value and this will be detrimental to the demultiplexed signals. The signal-control pulse walk-off can broaden the switching window of NOLM, make the window profile deviate fromits central position, and decrease its switching efficiency.

关键词： OTDM NOLM demultiplexer all-optical switch

Periodicity Characteristic of TOAD's Switching Window

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Chinese Journal of Lasers 2000年第2期9卷 161-166页

作者： LIU Xianbing,YE Peida (beijing university of posts and telecommunications, beijing 100876, china ) 北京邮电大学北京

The periodidity characteristic of switching window of a terahertz optical asymmetric demultiplexer (TOAD) using numerical simulation was investigated. The results show that the switching window width of TOAD changes periodically with the time asymmetry of TOAD and the period is one half of the period of control pulses. The theoretical results agree with the experimental results very well.

关键词： terahertz optical asymmetric demultiplexer (TOAD) Sendconductor optical amplifier (SOA) optical time division multiplexing (OTDM)

Threshold quantum secure direct communication without entanglement

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science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3 & WEN QiaoYan2 1 College of Computer science and Technology, beijing university of Technology, beijing 100022, china 2 school of science, beijing university of posts and telecommunications, beijing 100876, china 3 State Key Laboratory of Information Security (Graduate school of Chinese Academy of sciences), beijing 100049, china 1. College of Computer science and Technology Beijing University of Technology Beijing 100022 China 3. State Key Laboratory of Information Security (Graduate school of Chinese Academy of sciences) Beijing 100049 China 2. school of science Beijing University of Posts and Telecommunications Beijing 100876 China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

SVM-based loss differentiation algorithm for wired-cum-wireless networks

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The Journal of china Universities of posts and telecommunications 2009年第4期16卷 104-111页

作者： DENG Qian-hua ,CAI An-ni school of Telecommunication Engineering,beijing university of posts and telecommunications,beijing 100876,china [a]school of Telecommunication Engineering beijing university of posts and telecommunications beijing 100876 china

In a hybrid wired-cum-wireless network environment, packet loss may happen because of congestion or wireless link errors. Therefore, differentiating the cause is important for helping transport protocols take actions to control congestion only when the loss is caused by congestion. In this article, an end-to-end loss differentiation mechanism is proposed to improve the transmission performance of transmission control protocol （TCP）-friendly rate control （TFRC） protocol. Its key design is the introduction of the outstanding machine learning algorithm - the support vector machine （SVM） into the network domain to perform multi-metric joint loss differentiation. The SVM is characterized by using end-to-end indicators for input, such as the relative one-way trip time and the inter-arrival time of packets fore-and-aft the loss, while requiring no support from intermediate network apparatus. Simulations are carried out to evaluate the loss differentiation algorithm with various network configurations, such as with different competing flows, wireless loss rate and queue size. The results show that the proposed classifier is effective under most scenarios, and that its performance is superior to the ZigZag, mBiaz and spike （ZBS） scheme.

关键词： machine learning SVM TCP-friendly rate control (TFRC) congestion control

Robust multiuser MIMO scheduling algorithms with imperfect CSI

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science china(Information sciences) 2012年第4期55卷 815-826页

作者： MAO JunLing 1,3,GAO JinChun 1,3,LIU YuanAn 1,3,XIE Gang 2,3 & ZHANG Jian 1,3 1 school of Electronic Engineering,beijing university of posts and telecommunications,beijing 100876,china 2 school of Information and Communication Engineering,beijing university of posts and telecommunications,beijing 100876,china 3 Key Lab of Universal Wireless Communications,Ministry of Education,beijing university of posts and telecommunications,beijing 100876,china 1. school of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China3. Key Lab of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China2. School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Robust multiuser multiple-input-multiple-output (MIMO) scheduling algorithms are proposed in this *** imperfect channel state information (CSI),traditional scheduling algorithms for the multiuser MIMO system based on the zero forcing precoding scheme will lose some performance due to the multi-user interference (MUI).In order to improve the system average throughput,we study the robust multiuser MIMO scheduling problem with imperfect *** the average capacity formula,we derive a robust factor which can transform the robust multiuser MIMO scheduling problem into the traditional one,thus most existing non-robust scheduling algorithms can be robust if this factor is *** results show that compared with the traditional algorithms,the proposed robust algorithms can improve the system average throughput significantly under the CSI error environment.

关键词： multiuser MIMO (MU-MIMO) scheduling robust imperfect CSI