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Efficient practical codebook-precoding MIMO scheme based on signal space diversity

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Journal of Systems engineering and Electronics 2016年第1期27卷 1-9页

作者： Zhanji Wu xiang Gao school of information and communication engineering Beijing University of Posts and Telecommunications

A novel practical codebook-precoding multiple-input multiple-output（MIMO） system based on signal space diversity（SSD） with the minimum mean squared error（MMSE）receiver is *** scheme utilizes rotation modulation and space-time-frequency component interleaving.A novel precoding matrix selection criterion to maximize the average signal to interference plus noise ratio（SINR） is also put forward for the proposed scheme,which has a larger average mutual information（AMI）.Based on the AMI- maximization criterion,the optimal rotation angles for the proposed system are also *** new scheme can make full use of space-time-frequency diversity and signal space diversity,and exhibit high spectral efficiency and high reliability in fading *** results show that the proposed scheme greatly outperforms the conventional bit- interleaved coded modulation（BICM） MIMO-orthogonal frequency division multiplexing（OFDM） scheme without SSD,which is up to4.5 dB signal-to-noise ratio（SNR） gain.

关键词： signal space diversity(SSD) average mutual information(AMI) Turbo code multiple-input multiple-output(MIMO) minimum mean squared error(MMSE).

An Effective Cloud Workflow Scheduling Approach Combining PSO and Idle Time Slot-Aware Rules

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IEEE/CAA Journal of Automatica Sinica 2021年第5期8卷 1079-1094页

作者： yun Wang Xingquan Zuo the school of Computing Science Beijing University of Posts and TelecommunicationsBeijing 100876China the school of information engineering Nanchang Institute of TechnologyNanchang 330099China the Key laboratory of Trustworthy Distributed Computing and Service(BUPT) Ministry of EducationBeijing 100876China

Workflow scheduling is a key issue and remains a challenging problem in cloud *** with the large number of virtual machine(VM)types offered by cloud providers,cloud users need to choose the most appropriate VM type for each *** task scheduling sequences exist in a workflow *** task scheduling sequences have a significant impact on the scheduling *** is not easy to determine the most appropriate set of VM types for tasks and the best task scheduling ***,the idle time slots on VM instances should be used fully to increase resources'utilization and save the execution cost of a *** paper considers these three aspects simultaneously and proposes a cloud workflow scheduling approach which combines particle swarm optimization(PSO)and idle time slot-aware rules,to minimize the execution cost of a workflow application under a deadline constraint.A new particle encoding is devised to represent the VM type required by each task and the scheduling sequence of *** idle time slot-aware decoding procedure is proposed to decode a particle into a scheduling *** handle tasks'invalid priorities caused by the randomness of PSO,a repair method is used to repair those priorities to produce valid task scheduling *** proposed approach is compared with state-of-the-art cloud workflow scheduling *** show that the proposed approach outperforms the comparative algorithms in terms of both of the execution cost and the success rate in meeting the deadline.

关键词： Cloud computing idle time slot particle swarm optimization task scheduling sequence workflow scheduling

Improved MIMO-OFDM scheme for the next generation WlAN

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Journal of Systems engineering and Electronics 2013年第1期24卷 52-59页

作者： Zhanji Wu xiang Gao school of information and communication engineering Beijing University of Posts and Telecommunications

The research and application of wireless local area networks （WlAN） technology are in a stage of rapid development. It has been one of research focuses of the wireless communications field. Through the use of enhanced single-user （SU）/multi-user （MU） multiple input multiple output （MIMO）-orthogonal frequency division multiplexing （OFDM） technology, the next generation WlAN IEEE 802.1 lac dramatically increases the throughput. An improved MIMO-OFDM scheme based on modulation diversity is proposed for the next generation WlAN. It uses two-dimensional modulation diversity to the current IEEE 802.11ac transmission scheme. Through the space-time-frequency component inter- leaver and the rotational modulation, the proposed scheme ex- hibits high spectral efficiency and low error rate in fading channels. The simulation results show that the proposed scheme significantly outperforms the SU/MU MIMO-OFDM scheme in the current IEEE 802.11 ac standard, which is up to 5 dB.

关键词： wireless local area networks (WlAN) I EEE 802.1 lac modulation diversity multiple input multiple output (MIMO) orthog- onal frequency division multiplexing (OFDM).

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亮桥与冕环关系的研究进展

天文学进展 2024年第3期42卷 429-442页

作者：苗玉虎邓林华苏江涛管明祥邹海鑫夏林中曹雪梅华韵之刘煜袁丁深圳信息职业技术学院信息与通信学院深圳518172 云南民族大学数学与计算机科学学院昆明650504 哈尔滨工业大学(深圳)空间科学与应用技术研究院深圳518055 云南省太阳物理与空间目标监测重点实验室昆明650216 中国科学院国家天文台北京100101 中国科学院大学北京100049 西南交通大学物理科学与技术学院成都610031

亮桥是太阳黑子内部一种常见的结构,通常在亮桥区域会产生一系列的爆发活动,并对黑子演化产生影响。利用太阳动力学天文台(Solar Dynamics Observatory,SDO)搭载的大气成像阵列(Atmospheric Imaging Assembly,AIA)极紫外成像数据和日震... 详细信息

亮桥是太阳黑子内部一种常见的结构,通常在亮桥区域会产生一系列的爆发活动,并对黑子演化产生影响。利用太阳动力学天文台(Solar Dynamics Observatory,SDO)搭载的大气成像阵列(Atmospheric Imaging Assembly,AIA)极紫外成像数据和日震学与磁场成像仪(Helioseismic and Magnetic Imager,HMI)视向磁图和矢量磁图,通过统计大数据样本,表明亮桥与冕环之间的抑制特征具有一定的普遍性。冕环缺失区域主要位于亮桥锚定点附近的本影-半影边界上,在该区域,随着亮桥的演化和形态的改变,冕环也表现出显现和消失现象。通过分析HMI磁图数据,亮桥锚定区通常伴随着极性相反的小尺度磁场结构,可以推断亮桥锚定点区域的磁力线与周围相反极性的小尺度磁场结构相连,并形成短程闭合磁环,由于磁环的长度较短,无法延伸到日冕层,因此在日冕层无法观测到冕环。根据研究结果,提出了亮桥与冕环关系模型,用来解释亮桥与冕环之间的磁连接性,这个模型可以解释许多与亮桥相关的物理过程。

关键词：太阳活动太阳黑子太阳磁场

基于IPFS-DEMATEl-ISM的容器安全威胁关键战术要素研究

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中国安全科学学报 2024年第6期34卷 157-163页

作者：盛剑桥曾丽帆方圆吴俊国网安徽省电力有限公司信息通信分公司安徽合肥230041 北京邮电大学经济管理学院北京100876

为解决电力能源企业“上云”引发的云原生容器安全威胁问题,提出融合区间毕达哥拉斯模糊集(IPFS)、决策试验与评价实验室(DEMATEl)和解释结构模型法(ISM)识别容器安全关键战术要素。首先,基于IPFS提取安全专家对容器入侵威胁战术要素的... 详细信息

为解决电力能源企业“上云”引发的云原生容器安全威胁问题,提出融合区间毕达哥拉斯模糊集(IPFS)、决策试验与评价实验室(DEMATEl)和解释结构模型法(ISM)识别容器安全关键战术要素。首先,基于IPFS提取安全专家对容器入侵威胁战术要素的经验判断,其次,应用DEMATEl和ISM识别容器安全威胁的关键战术要素及要素间的层级拓扑关系。结果表明:持久化和权限提升2个战术阶段的中心度和原因度较高,在整个云原生安全威胁体系中居于核心地位,这2个阶段的安全攻击行为需持高优先级关注;执行和持久化战术阶段的威胁攻击是云原生容器安全的本质要素,初始访问、窃取凭证以及横向移动战术阶段的威胁最直接影响云原生容器安全。研究提出的IPFS-DEMATEl-ISM法相较DEMATEl-ISM和集成三角模糊数的DEMATEl-ISM法在识别容器安全威胁关键战术要素时具有更好区分度和简约解释性。

关键词：区间毕达哥拉斯模糊集(IPFS) 决策试验与评价实验室(DEMATEl) 解释结构模型(ISM) 容器安全威胁关键战术要素

延迟容忍网络中基于分离时间和副本控制的路由算法

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北京邮电大学学报 2011年第2期34卷 113-117页

作者：刘期烈潘英俊李云王祥重庆邮电大学移动通信重点实验室重庆400065 重庆大学光电技术及系统教育部重点实验室重庆400044

延迟容忍网络中,基于历史消息转发路由协议可根据节点的历史统计信息对下一跳节点进行预测估计,以此判断转发和存储信息的最佳时机,避免信息盲目转发.为此,针对典型spray and focus协议选择中间节点的盲目性,将"分离时间"和"副本控制"... 详细信息

延迟容忍网络中,基于历史消息转发路由协议可根据节点的历史统计信息对下一跳节点进行预测估计,以此判断转发和存储信息的最佳时机,避免信息盲目转发.为此,针对典型spray and focus协议选择中间节点的盲目性,将"分离时间"和"副本控制"运用于路由选择、缓存管理和组播方式中,可较好地节约资源,并提高通信效率.仿真结果表明,改进后的协议有效地提高了网络交付率,减小了端到端的时延.

关键词：延迟容忍网络分离时间副本控制缓存管理组播路由

Optimized lDPC differential-encoded 16QAM scheme for high-speed transmission systems

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Journal of Systems engineering and Electronics 2014年第5期25卷 728-734页

作者： Zhanji Wu xiang Gao Zhiyu Xiao school of information and communication engineering Beijing University of Posts and Telecommunications Huawei Technology limited Corporation

The 16-ary quadrature amplitude modulation （16QAM） is a high spectral efficient scheme for high-speed transmission systems. To remove the phase ambiguity in the coherent detection system, differential-encoded 16QAM （DE-16QAM） is usually used, however, it will cause performance degradation about 3 dB as compared to the conventional 16QAM. To overcome the performance loss, a serial concatenated system with outer low density parity check （lDPC） codes and inner DE-16QAM is proposed. At the receiver, joint iterative differential demodulation and decoding （ID） is carried out to approach the maximum likelihood performance. Moreover, a genetic evolution algorithm based on the extrinsic information transfer chart is proposed to optimize the degree distribution of the outer lDPC codes. Both theoretical analyses and simulation results indicate that this algorithm not only compensates the performance loss, but also obtains a significant performance gain, which is up to 1 dB as compared to the conventional non-DE-16QAM.

关键词： quadrature amplitude modulation (QAM) low density parity check (lDPC) code genetic evolution (GE) algorithm iterative demodulation and decoding (ID) extrinsic information transfer (EXIT) chart.

Performance-enhanced and cost-effective triboelectric nanogenerator based on stretchable electrode for wearable SpO2 monitoring

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Nano Research 2022年第3期15卷 2465-2471页

作者： Huamin Chen Wei Yang Cheng Zhang Mingqiang Wu Wenjie li Yuxiao Zou longfeng lv Hualiang Yu Huizhen Ke Ruping liu yun Xu jun Wang Zhou li Fujian Key laboratory of Functional Marine Sensing Materials Center for Advanced Marine Materials and Smart SensorsMinjiang UniversityFuzhou 350108China CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100083China Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China beijing Key laboratory of Inorganic Stretchable and Flexible information Technology Beijing 100083China beijing Institute of Graphic communication Beijing 102600China school of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China Fujian Key laboratory of Novel Functional Textile Fibers and Materials Minjiang UniversityFuzhou 350108China

Recently,stretchable and wearable health monitoring equipment has greatly improved human’s daily life,which sets higher demands for portable power source in stretchability,sustainability,and *** this work,we proposed a stretchable triboelectric nanogenerator(TENG)based on stretchable poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)/porous carbon hybrid for oxyhemoglobin saturation(SpO2)*** combine advantages of carbon material for its high conductivity and organic electrode for its high stretchability,we spin-coated a solution of PEDOT:PSS/porous carbon onto a plasma-treated pre-stretched Ecoflex film to fabricate a stretchable electrode with rough *** to its roughness and high potential difference with the dielectric material,the stretchable-electrode-based TENG exhibited better performance compared to the pristine TENG based on carbon or PEDOT:PSS *** output voltage and current reached up to 51.5 V and 13.2μA as the carbon concentration *** importantly,the performance further increased under large strain(100%)which is suitable for wearable ***,the device demonstrated its application potential for powering a flexible blood oxygen *** simple and cost-effective method can enhance the stretchability and stability of organic/inorganic electrode-based TENG,which paves the development of high-performance stretchable TENG.

关键词： triboelectric nanogenerator stretchable porous carbon blood oxygen poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS) wearable electronic

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意图驱动光网络的冲突解决方法

光通信技术 2024年第1期48卷 74-79页

作者：王寒凝王江齐钰滕云杨辉 61932部队北京100000 北京邮电大学信息光子学与光通信国家重点实验室北京100876

在意图驱动光网络中,由于同时下发的意图数量突然增多或底层物理资源的限制,部分用户的意图请求无法连接成功,导致意图冲突。提出一种基于强化学习的意图驱动光网络的冲突解决方法,根据强化学习输出的用户意图回退策略,更新用户意图对... 详细信息

在意图驱动光网络中,由于同时下发的意图数量突然增多或底层物理资源的限制,部分用户的意图请求无法连接成功,导致意图冲突。提出一种基于强化学习的意图驱动光网络的冲突解决方法,根据强化学习输出的用户意图回退策略,更新用户意图对应的网络需求指标,在保障用户意图都能够成功连接的前提下使当前网络中的平均服务质量(QoS)值最大。实验结果表明,提出的方法可以有效提升当前网络环境中用户的平均QoS值,降低网络阻塞率。

关键词：意图驱动光网络意图冲突强化学习用户协商平均服务质量