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Accurate inference of user popularity preference in a large-scale online video streaming system

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Science China(Information Sciences) 2018年第1期61卷 264-266页

作者： Xiaoying TAN Yuchun Guo yishuai chen Wei ZHU School of Electronics and Information Engineering Beijing Jiaotong University

With the fast growth of online video services,the service providers pursue to satisfy users’personal *** of them have noticed the diversity of users’preferences on video content but not that on video *** Goel ***.[1]proved in other domains that users have different popularity preferences(PPs)and Oh ***.[2]used the statistics of users’PPs to improve recommendation ***,the statistical

关键词： PP Accurate inference of user popularity preference in a large-scale online video streaming system

How time latency in navigation Apps affects traffic

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The Journal of China Universities of Posts and Telecommunications 2022年第6期29卷 53-63页

作者： Yang Jingjing Guo Yuchun Zhao Yongxiang chen yishuai School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China

With the recent increase in routing App usage, it is urgent to analyze the impact of inevitable information delay in routing Apps on *** analyze the negative impact of such delayed routing Apps on traffic, this paper investigates the impact of ideal and delayed routing Apps on traffic. Firstly, the effect of ideal routing Apps has been explored with theoretical analysis and derivation based on a macroscopic network model. Then, an extended network model is built to characterize the delayed *** impact of such delayed routing Apps is investigated by simulation experiments while considering routing usage proportion and amount of delay. The results demonstrate that ideal navigation does improve traffic efficiency, but in some cases, delayed navigation is even worse than no navigation.

关键词： traffic network delayed routing system performance

Optimized bandwidth allocation for maximizing user's QoE in hybrid cloud P2P content distribution

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The Journal of China Universities of Posts and Telecommunications 2015年第3期22卷 84-91页

作者： Zhang Yi Guo Yuchun chen yishuai School of Electronics and Information Engineering Beijing Jiaotong University

Hybrid cloud peer to peer （P2P） system is widely used for content distribution by utilizing user＇s capabilities to relieve the cloud bandwidth pressure. However, as demands for large-size files grow rapidly, it is a challenge to support high speed downloading experience simultaneously in different swarms with limited cloud bandwidth resource in such system. Therefore, it requires an optimized cloud bandwidth allocation to improve overall downloading experience of users. In this paper, we propose a system performance model which characterizes the relationship between cloud uploading bandwidth and user download speed. Based on the model, we study the cloud uploading bandwidth allocation, with the goal of optimizing user＇s quality of experience （QoE） that mainly depends on downloading rate of desired contents. Furthermore, to decrease the computation complexity, we put forward a heuristic algorithm to approximate the optimized solution. Simulation results show that our heuristic algorithm can obtain higher user＇s QoE as compared with two typical bandwidth allocation algorithms.

关键词： bandwidth allocation hybrid cloud P2P system quality of experience (QoE)

User friendly preferential private recommendation

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The Journal of China Universities of Posts and Telecommunications 2022年第3期29卷 43-53页

作者： Yang Jingjing Guo Yuchun Feng Tingting chen yishuai School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China China Unicom Network Technology Research Institute Beijing 100044China

To provide preferential protection for users while keeping good service utility, a preferential private recommendation framework(named as PrefER) is proposed. In this framework, a preferential budget allocation scheme is designed and implemented at the system side to provide multilevel *** users’ preference is utilized at the user side to improve recommendation performance without increasing users’ burden. This framework is generic enough to be employed with other schemes. Recommendation accuracy based on the MovieLens dataset by the collaborative filtering schemes and PrefER are compared and *** experimental results show that PrefER can provide preferential privacy protection with the improvement of recommendation accuracy.

关键词： preferential privacy protection differential privacy top-k recommendation personalized service

Wideband MIMO Radar Waveform Optimization Based on Range Profile

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Journal of Beijing Institute of Technology 2019年第1期28卷 137-145页

作者： Qun Zhang yishuai Gong Yijun chen Institute of Information and Navigation Air Force Engineering University Collaborative Innovation Center of Information Sensing and Understanding

Aiming at the signal bandwidth design problem for multi-target imaging task,a kind of multiple input multiple output(MIMO)radar waveform design method is *** first,the closed-loop feedback between the range profile and the signal bandwidth,which can design the minimum bandwidth of a transmitting signal that can distinguish each scatterer of the target in range direction,is ***,considering the request of beam pattern and the bandwidth limitation,a waveform optimization model is established and ***,the multi-target observation and the dynamic adjustment of the signal bandwidth are *** the end,the simulation results prove the performance of the algorithm in a low SNR circumstance.

关键词： multiple input multiple output(MIMO)radar cognition waveform design range profile range resolution

Will Tax Burden Be a Stumbling Block to Carbon-Emission Reduction? Evidence from OECD Countries

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Journal of Systems Science and Information 2021年第4期9卷 335-355页

作者： yishuai REN Yong JIANG Chaoqun MA Jianglong LIU Jing chen School of Public Administration Hunan UniversityChangsha 410082China Research Institute of Digital Society and Blockchain Hunan UniversityChangsha 410082China Centre for Resource and Environmental Management Hunan UniversityChangsha 410082China China Institute for Urban-Rural Development and Community Governance Hunan UniversityChangsha 410082China The Energy Centre University of AucklandAuckland 1142New Zealand School of Finance Nanjing Audit UniversityNanjing 211815China Business School Hunan UniversityChangsha 410082China School of Economics and Management Xidian UniversityXVan 710071China College of Natural Sciences and Mathematics The University of West AlabamaLivingston 35470USA

The influence of taxation on the economy and society is everywhere. Given the fact that CO_(2) emission is closely connected with human activities, the question naturally arises whether the tax burden affects the carbon emissions. To address this issue, based on the data of 21 OECD countries over the period from 1991–2014, we use the ratio of tax revenue to GDP as a proxy of the tax burden and employ a panel quantile model with the non-additive fixed effects for analysis. The results suggest that the impact of the tax burden on carbon emissions is heterogeneous across countries based on the level of carbon emissions. Moreover, we find a stable U-shaped relationship between the tax burden and carbon emissions whether for countries with a high or low level of carbon emissions. Our findings suggest that moderate taxes could help reduce carbon emissions, but the effect of excessive taxation is the opposite.

关键词： tax burden carbon emissions panel quantiles OECD countries

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面向成像任务的宽带MIMO雷达认知波形设计

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西安交通大学学报 2018年第6期52卷 114-121页

作者：龚逸帅李开明张群陈怡君空军工程大学信息与导航学院西安710077 信息感知技术协同创新中心西安710077 武警工程大学信息工程学院西安710086

为了利用最少的带宽资源,获取多个方向目标满意的成像结果,提出了一种信号带宽动态调整的宽带MIMO雷达认知波形设计方法。通过建立目标一维距离像与发射信号带宽之间的闭环反馈,使雷达可根据目标的粗分辨一维距离像,设计在距离向上每一... 详细信息

为了利用最少的带宽资源,获取多个方向目标满意的成像结果,提出了一种信号带宽动态调整的宽带MIMO雷达认知波形设计方法。通过建立目标一维距离像与发射信号带宽之间的闭环反馈,使雷达可根据目标的粗分辨一维距离像,设计在距离向上每一个散射点所需的最小发射信号带宽。在此基础上,综合考虑发射方向图和在目标方向所合成发射信号的带宽要求,建立波形认知优化模型并对其进行求解,最终实现了多目标观测时发射信号带宽的动态调整。仿真实验表明,在信噪比为-10dB条件下,该方法可以准确计算出各目标在距离向上最近两散射点之间的距离,并且可在最少消耗带宽资源的条件下实现目标逆合成孔径雷达成像,该成像结果与大带宽线性调频信号的成像结果十分相近。

关键词： MIMO雷达认知波形设计一维距离像

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基于图卷积神经网络的乳腺癌亚型分类研究

生物医学工程学杂志 2024年第1期41卷 121-128页

作者：安义帅刘晓军陈恒玲万桂宏中南民族大学生物医学工程学院武汉430074 哈佛大学麻省总医院皮肤科波士顿02138

恶性肿瘤分子亚型的准确识别是肿瘤患者个体化诊断、个性化治疗以及预后预测的重要支撑。综合性肿瘤基因组数据库的不断完善和深度学习技术的持续突破,推动了计算机辅助肿瘤分类技术的进一步发展。现有的基于基因表达数据的神经网络亚... 详细信息

恶性肿瘤分子亚型的准确识别是肿瘤患者个体化诊断、个性化治疗以及预后预测的重要支撑。综合性肿瘤基因组数据库的不断完善和深度学习技术的持续突破,推动了计算机辅助肿瘤分类技术的进一步发展。现有的基于基因表达数据的神经网络亚型分类方法虽然考虑了分子分型的复杂性,但仍然存在忽略基因内在关联性和协同性的问题。为了解决这一问题,本文提出了一种结合分层注意力机制的多层图卷积神经网络乳腺癌亚型分类模型。该模型基于先验的生物学知识构建乳腺癌患者的基因图表示数据集,训练出一种新的端到端的多分类模型,能够对乳腺癌分子亚型进行智能识别,并且在乳腺癌分子亚型的分类工作上表现出了很好的识别性能。相较于原始的图卷积神经网络以及两个主流的图神经网络分类算法,该模型在7分类任务中的准确率、加权F1分数、加权召回率、加权精确率分别达到了0.8517、0.8235、0.8517、0.7936,在4分类任务中则分别达到了0.9285、0.8949、0.9285、0.8650,具有明显的优势。此外,本文方法相较于最新的乳腺癌亚型分类算法,同样获得了最高的分类准确率。综上,本文所提模型或可作为一种辅助诊断技术为未来乳腺癌亚型的精确分类提供一个可信的选择,奠定计算机辅助肿瘤分类的理论基础。

关键词：乳腺癌深度学习图卷积神经网络亚型分类

基于跟踪脉冲的MIMO雷达多目标微动特征提取

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雷达学报（中英文） 2018年第5期7卷 575-584页

作者：罗迎龚逸帅陈怡君张群空军工程大学信息与导航学院中国人民解放军95561部队武警工程大学信息工程学院

微动特征是空间目标识别的重要特征信息之一。然而,现有的多功能多输入多输出(Multi-Input MultiOutput, MIMO)雷达通常需要在完成目标搜索和跟踪任务之后为目标微动特征提取分配大量连续的时间资源,导致目标识别实时性能和雷达系统整... 详细信息

微动特征是空间目标识别的重要特征信息之一。然而,现有的多功能多输入多输出(Multi-Input MultiOutput, MIMO)雷达通常需要在完成目标搜索和跟踪任务之后为目标微动特征提取分配大量连续的时间资源,导致目标识别实时性能和雷达系统整体工作性能均不高。针对该问题,该文提出了一种基于跟踪脉冲的MIMO雷达多目标微动特征提取方法。首先依据各目标的方位信息对MIMO雷达发射波形进行设计,为不同方向目标同时发射跟踪脉冲;在此基础上,综合考虑目标微动特征提取性能以及目标跟踪性能的需求,对跟踪脉冲的发射时间序列进行优化设计;最后,直接利用窄带跟踪脉冲实现对不同方向目标微动特征的同时提取,无需再为目标微动特征提取分配额外的时间资源,有效提升目标识别实时性和雷达工作效率。仿真实验表明,在信噪比大于–10 dB时,所提方法能够实现多目标微动特征的准确提取,具有良好的有效性和鲁棒性。

关键词： MIMO雷达微动特征多目标跟踪脉冲