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Joint Multi-User Detection with Weighting Factors for Unsourced Multiple Access
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作者 Yu Liu Kai Niu Yuanjie Li 《Journal of Computer and Communications》 2023年第9期121-131,共11页
Multi-user detection techniques are currently being studied as highly promising technologies for improving the performance of unsourced multiple access systems. In this paper, we propose joint multi-user detection sch... Multi-user detection techniques are currently being studied as highly promising technologies for improving the performance of unsourced multiple access systems. In this paper, we propose joint multi-user detection schemes with weighting factors for unsourced multiple access. First, we introduce bidirectional weighting factors in the extrinsic information passing process between the multi-user detector based on belief propagation (BP) and the LDPC decoder. Second, we incorporate bidirectional weighting factors in the message passing process between the MAC nodes and the user variable nodes in BP- based multi-user detector. The proposed schemes select the optimal weighting factors through simulations. The simulation results demonstrate that the proposed schemes exhibit significant performance improvements in terms of block error rate (BLER) compared to traditional schemes. . 展开更多
关键词 COMMUNICATION Sparse IDMA multi-user Detection Belief Propagation
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Development Of Multi-users Multi-function Watt-hour Meter Based On ATT7022B
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作者 Mao-fa GONG~1,Chang-lun HU~1,Jing-yin HE~2,Xiao-ming ZHANG~1,Long-qing CHAI~1 (1.Collage of information and electrical engineering,Shandong University Of Science and Technology,Qingdao266510,China 2.Qingdao Technical Collage,Qingdao 266555,China) 《Journal of Measurement Science and Instrumentation》 CAS 2010年第S1期123-125,共3页
According to the feature of city’s apartment building in China,a kind of Multi-users Watt-hour Meter based on ATT7022B has been developed in this paper.The master-slave MCU control model and the principles of Time Sh... According to the feature of city’s apartment building in China,a kind of Multi-users Watt-hour Meter based on ATT7022B has been developed in this paper.The master-slave MCU control model and the principles of Time Sharing Multiplex are adopted in this Watt-hour Meter,its function includes the measurement of current, voltage,power,power factor and the overload protection.It supports remote reading,pre-payment,multi-rate and etc. The practice shows that this meter has high accuracy,runs stable.It has wide prospect in the future market. 展开更多
关键词 multi-users ATT7022B Time Sharing multiplex Master-Slave Control Mode
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用户偏好-制造商偏好双重视阈下的产品创新机会识别路径研究 被引量:1
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作者 王金凤 仵轩 +2 位作者 冯立杰 张珂 刘鹏 《计算机集成制造系统》 EI CSCD 北大核心 2024年第4期1433-1445,共13页
精准识别产品创新机会对制造商规避盲目创新风险,持续获取竞争优势至关重要。针对现有产品创新机会识别研究中因视角单一致使制造商价值创造的效率难以最大化,以及识别的创新机会聚焦度不清晰等诸多问题,基于用户偏好制造商偏好双重视... 精准识别产品创新机会对制造商规避盲目创新风险,持续获取竞争优势至关重要。针对现有产品创新机会识别研究中因视角单一致使制造商价值创造的效率难以最大化,以及识别的创新机会聚焦度不清晰等诸多问题,基于用户偏好制造商偏好双重视阈构建了产品创新机会识别路径。首先,运用结构主题模型从用户在线评论和产品描述文本中分别提取用户偏好及制造商偏好的产品属性主题;其次,基于两类主题之间的相似度进行主题分类以获取具象产品的创新需求;再次,从现有相关专利中提取创新要素并依托多维技术创新地图识别产品创新机会;最后,以老年智能手环靶向开展产品创新机会识别为例,验证了所提路径的可行性。应用结果表明,构建的用户偏好制造商偏好双重视阈下的产品创新机会识别路径能够为制造商高效开展产品创新活动提供可资借鉴的决策理论支持。 展开更多
关键词 产品创新机会识别 用户偏好制造商偏好双重视阈 多维技术创新地图 结构主题模型
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基于Wi-Fi感知的多用户身份识别研究
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作者 魏忠诚 陈炜 +3 位作者 董延虎 连彬 王巍 赵继军 《物联网学报》 2024年第1期111-121,共11页
随着无线感知技术的发展,基于Wi-Fi的身份识别研究在人机交互和家居安防等领域备受关注。尽管基于Wi-Fi信号的身份识别已经取得了初步的成功,但是目前主要适用于用户独立行为场景,并发行为下的多用户身份识别仍然面临着一系列挑战,包括... 随着无线感知技术的发展,基于Wi-Fi的身份识别研究在人机交互和家居安防等领域备受关注。尽管基于Wi-Fi信号的身份识别已经取得了初步的成功,但是目前主要适用于用户独立行为场景,并发行为下的多用户身份识别仍然面临着一系列挑战,包括用户之间的相互干扰以及模型鲁棒性差等问题。因此,提出了一种并发行为下多用户身份识别系统Wiblack,其核心思想是训练一个多分支深度神经网络(Wiblack-Net)来提取每个单用户的独特特征。首先,利用主干网络提取多用户之间的共同特征;然后,为每个用户分配一个二分类器以此判断给定群体中是否存在目标用户,在此基础上基于并发行为实现多个用户身份识别。此外,将Wiblack与多个独立的二分类模型和单个多分类模型进行对比实验,对运行效率和系统性能进行分析。实验结果显示,在同时识别3个用户身份时,Wibalck平均准确率达到了92.97%,平均精确度为93.71%,平均召回率为93.24%,平均F1值为92.43%。 展开更多
关键词 Wi-Fi感知 信道状态信息 身份识别 多人识别 多分支深度神经网络
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多源域迁移学习的肌电-惯性特征融合及手势识别
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作者 谢平 赵连洋 +3 位作者 张艺滢 徐猛 江国乾 陈杰 《电子测量与仪器学报》 CSCD 北大核心 2024年第7期187-195,共9页
在跨用户手势识别研究中,针对单源域迁移学习存在的负迁移和模型泛化性能差的问题,本研究创新性地提出了一种基于肌电-惯性特征融合的多源域迁移学习策略,关键创新点在于整合多个源域的数据,并在此基础上采用域特有特征对齐与域分类器... 在跨用户手势识别研究中,针对单源域迁移学习存在的负迁移和模型泛化性能差的问题,本研究创新性地提出了一种基于肌电-惯性特征融合的多源域迁移学习策略,关键创新点在于整合多个源域的数据,并在此基础上采用域特有特征对齐与域分类器对齐的技术手段。这一方法旨在强化模型在不同用户间的手势识别性能,进而显著提升跨用户手势识别系统的准确性。首先,引入长短时记忆(long short-term memory, LSTM)网络模型,提取肌电-惯性信息的平均绝对值、方差、峰值等时序特征;其次进行域特有特征对齐与域分类器对齐,利用多个源域数据完成对目标域的特征提取;最后融合分类损失、域特有特征差异损失和域分类器差异损失3个损失函数,协同优化整体损失。实验结果表明,所提方法与单源域、源域组合等多种传统方法相比,识别平均率有所提高,在NinaPro DB5数据集上,目标用户的手势识别平均准确率达到80%以上。 展开更多
关键词 肌电-惯性信号 跨用户手势识别 多源域迁移学习 长短时记忆网络 特征对齐
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基于DTW K-medoids与VMD-多分支神经网络的多用户短期负荷预测 被引量:2
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作者 王宇飞 杜桐 +3 位作者 边伟国 张钊 刘慧婷 杨丽君 《中国电力》 CSCD 北大核心 2024年第6期121-130,共10页
多用户电力负荷预测是指根据历史负荷数据对多个用户或区域的电力负荷进行预测,可使电网企业掌握不同用户或区域的电力需求,以便更好地开展规划和实施调度优化等。然而由于各用户呈现出复杂多样的用电行为,采用传统方法难以进行统一建... 多用户电力负荷预测是指根据历史负荷数据对多个用户或区域的电力负荷进行预测,可使电网企业掌握不同用户或区域的电力需求,以便更好地开展规划和实施调度优化等。然而由于各用户呈现出复杂多样的用电行为,采用传统方法难以进行统一建模并实现快速准确预测。为此,构建了一种基于DTW Kmedoids与VMD-多分支神经网络的多用户短期负荷预测模型。首先,采用DTW K-medoids法进行用户负荷数据聚类,利用动态时间弯曲(dynamic time warping,DTW)计算数据间的距离,取代K-medoids算法中传统的欧氏距离度量方式,以改善多用户负荷聚类的效果;在此基础上,为充分表征负荷历史数据的长短期时序依赖特征,建立了一种基于变分模态分解(variational mode decomposition,VMD)-多分支神经网络模型的并行预测方法,用于多用户短期负荷预测;最后,使用某地区20个用户365天的负荷数据进行聚类、训练和测试实验,结果显示该模型结果的平均绝对误差和均方根误差等指标均较对比模型有较大幅度降低,表明该方法可有效表征多类用户的用电行为,提升多用户负荷预测效率和精度。 展开更多
关键词 多用户 负荷预测 DTW K-medoids聚类 变分模态分解(VMD) 多分支神经网络
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A Linear Interference Cancellation Multi-User Detector for Synchronous CDMA Communications
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作者 卜志勇 尤肖虎 陈明 《Journal of Southeast University(English Edition)》 EI CAS 1998年第2期3-6,共4页
This paper describes a linear interference cancellation multi user detector for synchronous DS CDMA systems under the condition that all spread spectrum code waveforms have the constant cross correlating coefficien... This paper describes a linear interference cancellation multi user detector for synchronous DS CDMA systems under the condition that all spread spectrum code waveforms have the constant cross correlating coefficients. The basic idea is to get the estimation for total multiple access interference (MAI) of all users using a reference code waveform, then subtract the total MAI from the received signal. The structure of such a detector is nearly similar to the conventional detector. The BER expression obtained in the paper shows significant performance improvement compared to the other detectors. 展开更多
关键词 multi user detection linear interference cancellation constant cross correlation coefficients
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大规模离散MU-MIMO:低复杂度、信息理论最优检测与多用户编码
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作者 陈学辉 池育浩 刘雷 《中兴通讯技术》 北大核心 2024年第1期46-54,共9页
研究了一种实际的大规模离散多用户多输入多输出(MU-MIMO)系统,涵盖了大规模天线与用户、实用的信道编译码、任意输入分布、仅接收机已知信道状态信息、一般右酉不变信道矩阵、模数转化器等实际通信约束。针对理想和低分辨率模数转换器... 研究了一种实际的大规模离散多用户多输入多输出(MU-MIMO)系统,涵盖了大规模天线与用户、实用的信道编译码、任意输入分布、仅接收机已知信道状态信息、一般右酉不变信道矩阵、模数转化器等实际通信约束。针对理想和低分辨率模数转换器下的大规模离散MU-MIMO系统,分别提出了低复杂度、信息理论最优接收机和多用户码设计准则,并给出实际多用户低密度奇偶校验码(LDPC)设计。数值实验证实所设计的多用户LDPC比现有的单用户LDPC获得了2~5dB性能增益,同时还解决在信道恶劣和低分辨率模数转换器下单用户码无法准确恢复信息的难题,揭示了现有贝叶斯最优接收机与单用户码直接结合不再是最优方案。 展开更多
关键词 大规模离散MU-MIMO 低复杂度 信息理论最优 迭代接收机 多用户码
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公交-合乘车道优化设计的多目标双层规划模型
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作者 姚荣涵 徐文韬 +1 位作者 林子敬 王立冰 《汽车安全与节能学报》 CAS CSCD 北大核心 2024年第5期711-722,共12页
为提高公交专用道利用率,构建了公交-合乘车道(bus-HOV lanes)优化设计的多目标双层规划模型。该模型上层最小化交通总阻抗、公交运营成本和车辆排放;下层考虑非合乘车、合乘车和公交车实现多方式交通网络用户均衡;由快速非支配排序遗... 为提高公交专用道利用率,构建了公交-合乘车道(bus-HOV lanes)优化设计的多目标双层规划模型。该模型上层最小化交通总阻抗、公交运营成本和车辆排放;下层考虑非合乘车、合乘车和公交车实现多方式交通网络用户均衡;由快速非支配排序遗传算法求解,其下层由相继平均法和连续权重平均法求解;并使用Nguyen-Dupuis网络验证模型及其求解算法。结果表明:所给算法能有效获得公交-合乘车道设置方案的Pareto最优解集;合理的公交-合乘车道设置方案能有效促进合乘出行;相比不设置公交-合乘车道,全部和部分合乘车进入公交-合乘车道分别使交通总阻抗降低-0.007%~1.088%和0.038%~4.493%,使公交运营成本上升1.057%~3.864%和4.011%~5.611%,使车辆排放减少-7.598%~-1.111%和-0.677%~3.526%;当起讫点(OD)对客流量不低于其临界值,设置公交-合乘车道有利于增加公交车客流量。 展开更多
关键词 交通工程 双层规划模型 多目标优化 公交-合乘车道(bus-HOV lanes) 用户均衡
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Complex field network-coded cooperation based on multi-user detection in wireless networks 被引量:2
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作者 Jing Wang Xiangyang Liu +1 位作者 Kaikai Chi Xiangmo Zhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第2期215-221,共7页
Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation(CFNCC... Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation(CFNCC) scheme based on multi-user detection for the multiple unicast transmission is proposed.Theoretic analysis and simulation results demonstrate that,compared with the conventional cooperation(CC) scheme and network-coded cooperation(NCC) scheme,CFNCC would obtain higher network throughput and consumes less time slots.Moreover,a further investigation is made for the symbol error probability(SEP) performance of CFNCC scheme,and SEPs of CFNCC scheme are compared with those of NCC scheme in various scenarios for different signal to noise ratio(SNR) values. 展开更多
关键词 network coding complex field wireless network cooperative communication multi-user detection
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Multi-User Detection for Spatial Modulation toward 5G Wireless Communications 被引量:1
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作者 Shiwen Fan, Yue Xiao +3 位作者 Xia Lei Rong Shi Ke Deng Shaoqian Li 《China Communications》 SCIE CSCD 2017年第12期100-110,共11页
Spatial modulation(SM) is a class of novel multiple-input multiple-output(MIMO) techniques toward future wireless communications,which activates only one transmit antenna in each time slot,so as to reduce the number o... Spatial modulation(SM) is a class of novel multiple-input multiple-output(MIMO) techniques toward future wireless communications,which activates only one transmit antenna in each time slot,so as to reduce the number of RF chains for saving the implement cost.Meanwhile,considering its application in 5G systems with multiple users,the detection of multi-user spatial modulation has drawn greater attention.In this paper,a pair of efficient detectors are proposed for multi-user spatial modulation.Specially,a threshold-aided approximate message passing(T-AMP) detector is proposed with the purpose of reducing the computational complexity of traditional structured approximate message passing(Str-AMP) detector.In addition,a novel probability sorting aided approximate message passing detector,called probability-ranking-aided AMP detector(P-AMP),is also proposed with the purpose of improving the performance.Simulation results show that the proposed T-AMP detector is able to achieve similar performance as traditional StrAMP with lower complexity,while the proposed P-AMP detector exhibits a better symbol error rate(SER) performance with similar complexity. 展开更多
关键词 multi-user spatial modulation PROBABILITY SORTING MESSAGE passing.
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Joint Source and Relay Precoding/Beamforming Algorithm for OFDM Multi-user Cooperative Relay Systems 被引量:1
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作者 ZHOU Dong-yue HU Bin-jie 《Journal of Donghua University(English Edition)》 EI CAS 2014年第5期723-726,共4页
In order to reduce the feedback load of multi-user orthogonal frequency division multiplexing ( OFDM ) -based wireless systems, a practiral limited bits feedback precoding algorithm is proposed with direct source-de... In order to reduce the feedback load of multi-user orthogonal frequency division multiplexing ( OFDM ) -based wireless systems, a practiral limited bits feedback precoding algorithm is proposed with direct source-destination link based on amplify-and- forward cooperative relay network under frequency selective fading channels. Using joint minimum mean square error(MMSE) filter, the receiving decoding matrix is designed for each user in the paper. Source precoding (beamforming) matrix is optimized with convex function of weight mean square error (MSE). Relay precoding matrix is obtained under MSE decomposition and convex optimization. The precoding matrix index is fed back for clustered subcarrier of OFDM with limited feedback. Then using interpolation algorithm, all precoding matrices are achieved at base station (BS) and relay nodes. Simulations indicate the effectiveness of the proposed limited feedback joint precoding and beam_formlng design. The proposed method can improve bit error rate (BER) performance and obtain better sum-rate performance in contrast to existing algorithms. It displays the BER performance is close to that of the unquantified precoding feedback method. 展开更多
关键词 RELAY multi-user PRECODING mean square error (MSE) feedback BITS dual HOP
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Wavelet Packet Domain LMS Based Multi-User Detection 被引量:1
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作者 刘鹏 安建平 《Journal of Beijing Institute of Technology》 EI CAS 2008年第4期484-488,共5页
An improved wavelet packet domain least mean square (IWPD-LMS) based adaptive muhiuser detection algorithm is proposed. The algorithm employs the wavelet packet transform to rewhiten the input data, and chooses the ... An improved wavelet packet domain least mean square (IWPD-LMS) based adaptive muhiuser detection algorithm is proposed. The algorithm employs the wavelet packet transform to rewhiten the input data, and chooses the best wavelet packet basis according to a novel convergence contribution function rather than the conventional Shannon entropy. The theoretic analyses show that the inadequacy of the eigenvalue spread of the tap-input correlation matrix is ameliorated, thus the convergence performance is improved greatly. The simulation result of convergence performance and bit error rate(BER) performance as a function of the signal power to noise power ratio(SNR) are presented finally to prove the validity of the proposed algorithm. 展开更多
关键词 multi-user detection least mean square (LMS) wavelet packet wavelet packet basis
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Study of multi-rate multi-user detection based on supervision decision
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作者 杨涛 谢剑英 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第3期413-418,共6页
Multi-user detection (MUD) based on multirate transmission in code division multiple access (CDMA) system is discussed. Under the requirement of signal interference ratio (SIR) detection at base station and framework ... Multi-user detection (MUD) based on multirate transmission in code division multiple access (CDMA) system is discussed. Under the requirement of signal interference ratio (SIR) detection at base station and framework with parallel interference cancellation, a supervision decision algorithm based on pre-decision of probabilistic data association (PDA) and hard decision is proposed. The detection performance is analyzed and simulation is implemented to show that the supervision decision algorithm improves the detection performance effectively. 展开更多
关键词 CDMA multi-RATE multi-user detection supervision decision.
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5G异构网络中基于多目标Actor-Critic的资源分配
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作者 曾韦健 李晖 《国外电子测量技术》 2024年第6期33-40,共8页
在5G异构网络(heterogeneous network,HetNet)中广泛部署小基站可以提高网络容量和用户速率,但密集部署也会产生严重干扰和更高能耗问题。为了最大化网络能量效率(energy efficiency,EE)并保证用户服务质量(quality of service,QoS),提... 在5G异构网络(heterogeneous network,HetNet)中广泛部署小基站可以提高网络容量和用户速率,但密集部署也会产生严重干扰和更高能耗问题。为了最大化网络能量效率(energy efficiency,EE)并保证用户服务质量(quality of service,QoS),提出了一种在小蜂窝基站中嵌入能量收集器供电的资源分配方案。首先,针对网络系统的下行链路,将频谱和小基站发射功率分配问题建模为联合优化系统能效和用户满意度的多目标优化问题。其次,提出了基于深度强化学习的多目标演员-评论家(multi-objective actor-critic,MAC)资源分配算法求解所建立的优化模型。最后,仿真结果表明,相比于其他传统学习算法,能量效率提高了11.96%~12.37%,用户满意度提高了11.45%~27.37%。 展开更多
关键词 5G异构网络 能量效率 用户满意度 多目标优化 深度强化学习
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Zero-forcing beamforming with receiver antenna selection in downlink multi-antenna multi-user system
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作者 Huang Senhua Qiu Ling Shi Lin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1258-1263,共6页
A study on the zero-forcing beamforming (ZFBF) scheme with antenna selection at user terminals in downlink multi-antenna multi-user systems is presented. Simulation results show that the proposed ZFBF scheme with re... A study on the zero-forcing beamforming (ZFBF) scheme with antenna selection at user terminals in downlink multi-antenna multi-user systems is presented. Simulation results show that the proposed ZFBF scheme with receiver antenna selection (ZFBF-AS) achieves considerable throughput improvement over the ZFBF scheme with single receiver antenna. The results also show that, with multi-user diversity, the ZFBF-AS scheme approaches the throughput performance of the ZFBF scheme using all receiver antennas (ZFBF-WO-AS) when the base station adopts semi-orthogonal user selection (SUS) algorithm, and achieves larger throughput when the base station adopts the Round-robin scheduling algorithm. Compared with ZFBF-WO-AS, the proposed ZFBF-AS scheme can reduce the cost of user equipments and the channel state information requirement at the transmitter (CSIT) as well as the multiuser scheduling complexity at the transmitter. 展开更多
关键词 downlink multi-antenna multi-user system zero-forcing beamforming antenna selection throughput performance
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Impact of user influence on information multi-step communication in a micro-blog
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作者 吴越 胡勇 +1 位作者 何小海 邓垦 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期5-12,共8页
User influence is generally considered as one of the most critical factors that affect information cascading spreading. Based on this common assumption, this paper proposes a theoretical model to examine user influenc... User influence is generally considered as one of the most critical factors that affect information cascading spreading. Based on this common assumption, this paper proposes a theoretical model to examine user influence on the information multi-step communication in a micro-biog. The multi-steps of information communication are divided into first-step and non-first-step, and user influence is classified into five dimensions. Actual data from the Sina micro-blog is collected to construct the model by means of an approach based on structural equations that uses the Partial Least Squares (PLS) technique. Our experimental results indicate that the dimensions of the number of fans and their authority significantly impact the information of first-step conxrnunication. Leader rank has a positive impact on both first-step and non-first-step communication. Moreover, global centrality and weight of friends are positively related to the information non-first-step communication, but authority is found to have much less relation to it. 展开更多
关键词 user influence information multi-step communication micro-blog structural equations
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User Fairness Scheme with Proportional Fair Scheduling in Multi-user MIMO Limited Feedback System
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作者 Hongyu Wang Weixiao Meng Trungtan Nguyen 《Communications and Network》 2013年第3期113-118,共6页
In Multi-user MIMO (MU-MIMO) downlink system, suitable user selection schemes can improve spatial diversity gain. In most of previous studies, it is always assumed that the base station (BS) knows full channel state i... In Multi-user MIMO (MU-MIMO) downlink system, suitable user selection schemes can improve spatial diversity gain. In most of previous studies, it is always assumed that the base station (BS) knows full channel state information (CSI) of each user, which does not consider the reality. However, there are only limited feedback bits in real system. Besides, user fairness is often ignored in most of current user selection schemes. To discuss the user fairness and limited feedback, in this paper, the user selection scheme with limited feedback bits is proposed. The BS utilizes codebook precoding transmitting strategy with LTE codebook. Furthermore, this paper analyzes the influence of the number of feedback bits and the number of users on user fairness and system sum capacity. Simulation results show that in order to achieve better user fairness, we can use fewer bits for feedback CSI when the number of user is small, and more feedback bits when the number of users is large. 展开更多
关键词 user FAIRNESS SCHEME with Proportional FAIR Scheduling in multi-user MIMO LIMITED Feedback System
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An Efficient Noisy-ICA Based Approach to Multiuser Detection in IDMA Systems
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作者 Abdelkrim Hamza Salim Chitroub Gérard Salut 《International Journal of Communications, Network and System Sciences》 2010年第9期767-772,共6页
Interleaved Division Multiple Access (IDMA) is a new access scheme that has been proposed in the literature to increase the capacity of wireless channels. The performance of such systems depends on the accuracy of the... Interleaved Division Multiple Access (IDMA) is a new access scheme that has been proposed in the literature to increase the capacity of wireless channels. The performance of such systems depends on the accuracy of the channel state information at the receiver. In this paper, a Noisy-Independent Component Analysis (N-ICA) based IDMA receiver for multiple access communication channels is proposed. The N-ICA component is applied as a post processor. Unlike other IDMA receivers, the proposed scheme detects and separates the transmitted symbols without channel state information tracking. The performance of the proposed technique is presented in terms of raw bit error rate (BER) without channel coding for different signal to noise ratios (SNR). Simulation results demonstrate that N-ICA post processor provides an improvement in performance in terms of bit error rate (BER) in loaded systems. When the system is not loaded, the proposed post processor presents the same performance as conventional IDMA receiver with less iterations leading to a complexity reduction. 展开更多
关键词 IDMA ICA multi-user Detection
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Multi-user Motion JPEG2000 over wireless LAN: run-time performance-energy optimization with application-aware cross-layer scheduling
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作者 POLLIN Sofie LENOIR Gregory +2 位作者 LAFRUIT Gauthier DEJONGHE Antoine CATTHOOR Francky 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第z1期151-158,共8页
This paper introduces a video application-aware cross-layer framework for joint performance-energy optimization,considering the scenario of multiple users upstreaming real-time Motion JPEG2000 video streams to the acc... This paper introduces a video application-aware cross-layer framework for joint performance-energy optimization,considering the scenario of multiple users upstreaming real-time Motion JPEG2000 video streams to the access point of a WiFi wireless local area network and extends the PHY-MAC run-time cross-layer scheduling strategy that we introduced in (Mangharam et al., 2005; Pollin et al., 2005) to also consider congested network situations where video packets have to be dropped. We show that an optimal solution at PHY-MAC level can be highly suboptimal at application level, and then show that making the cross-layer framework application-aware through a prioritized dropping policy capitalizing on the inherent scalability of Motion JPEG2000 video streams leads to drastic average video quality improvements and inter-user quality variation reductions of as much as 10 dB PSNR, without affecting the overall energy consumption requirements. 展开更多
关键词 Performance-energy optimization Application-aware scheduling MOTION JPEG2000 WLAN multi-user transmission
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