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A System Simulation platform for 3.

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The Journal of china Universities of posts and telecommunications 2003年第3期10卷 74-78页

作者： LU Zheng xing, YANG Da cheng (Wireless research Center of beijing {3. of posts and telecommunications, beijing 100876, p. r. china) Wireless research Center of beijing university of posts and {3. Beijing 100876

A 3. system simulation platform is designed to research on and evaluate theeffects of various techniques of the 3. network p.r.ormance. The basic structure and principle ofthe simulation platform is presented and the ... 详细信息

关键词： system simulation mobile communications 3. network

Formation and causes of NOx pollution on the east side of the Taihang Mountains in china

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Science Bulletin 2011年第19期 2046-2051页

作者： TIAN HeZhong 1 , WANG Yan 1 , ZHAO Dan 1 , CHAI FaHe 2 , xing ZiShan 3.& cheng Ke 1 1 State Key Joint Laboratory of Environmental Simulation & pollution Control, School of Environment, beijing Normal {3., beijing 100875, china 2 Chinese research Academy of Environmental Sciences, beijing 100012, china 3.School of Computer Science and Technology, beijing {3. of posts and telecommunications, beijing 100876, china

Tropospheric column amounts of NO 2 from OMI/Aura products were applied to investigate the seasonal variation of NO x on the east side of the Taihang Mountains (ESTM) in china. The NO 2 concentration varied seasonally, with winter maxima and summer minima. To explore the causes of the heavy NO 2 pollution in this region, wind field simulations were conducted by using the Fifth-Generation NCAr/penn State Mesoscale Model (MM5). MM5 simulations showed that wind directions in the ESTM region were dominated by northeasterly and northwesterly winds throughout the year and to a lesser degree by southwesterlies. Elevated NO 2 concentrations (higher than 50×10 15 molec/cm 2 ) occurred in three meteorological situations: convergent wind fields (5 days), northeasterly winds (2 days), and calm days (1 day) in January. Although the local anthropogenic NO x emission strength was not so high as that in other developed areas, the calms and frequent occurrence of convergent wind fields, as well as unfavorable terrains for diffusion, resulted in the accumulation of atmospheric pollutants and hence heavy NO x pollution. Furthermore, long-distance NO x transp.r.ation from the beijing-Tianjin-Tangshan region to the ESTM area could be seen when the wind was from a northeasterly direction, especially under high wind speeds.

关键词： east side of the Taihang Mountains (ESTM) remote sensing of air pollution satellite data tropospheric NO 2 pollution wind field china

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一种新型轻小包裹高速分拣系统调度算法

系统工程 2024年第4期42卷 123-138页

作者：苏志远谭树勇李金澎程彬韦凌云北京邮电大学现代邮政学院北京100876

新型轻小包裹高速分拣系统综合应用两种不同类型的机器人(分拣机器人、料箱搬运机器人),首先分拣机器人将包裹先分拣至分拣区域内的周转料箱中,当周转料箱满箱后,料箱搬运机器人将之搬运至装箱区域打包。该系统可以基于分拣需求的变化... 详细信息

新型轻小包裹高速分拣系统综合应用两种不同类型的机器人(分拣机器人、料箱搬运机器人),首先分拣机器人将包裹先分拣至分拣区域内的周转料箱中,当周转料箱满箱后,料箱搬运机器人将之搬运至装箱区域打包。该系统可以基于分拣需求的变化动态调整分拣系统中机器人数目以及分拣区域面积大小,有利于降低分拣作业设备损耗及系统能耗。本文针对这种新型轻小包裹高速分拣系统调度问题展开研究,首先建立了综合考虑两种机器人、两阶段分拣过程(先分拣到周转料箱,再搬运周转料箱至打包位置)和动态分拣料口(分拣区域内周转料箱放置点不是固定的)的基于最低分拣成本的三维度调度模型;其次针对该调度模型两阶段三维度调度的特点,设计了一种两段三层可行解整数编码,及一种基于编码编辑距离(Levenshtein距离)的计算种群多样性的方法;然后,设计了一种结合两种变邻域算子(交换算子、贪心算子)和禁忌搜索的混合分散搜索算法,对模型进行求解;最后使用改进的MApF基准测试数据集,对上述模型和算法进行了验证。实验结果表明:本文提出的模型有效,能满足实际使用要求,求解算法的求解精度相较于标准遗传算法、标准分散搜索算法分别提升了10.3.和6.5%,收敛速度相较于标准分散搜索算法提升了15.5%,且数据集规模越大,本算法的收敛速度优势越突出。

关键词：轻小包裹分拣机器人调度变邻域禁忌搜索混合分散搜索

一种基于隐树模型的满足差分隐私的高维数据发布算法

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小型微型计算机系统 2018年第4期39卷 681-685页

作者：苏炜航程祥中国人民大学附属中学北京100080 北京邮电大学网络与交换技术国家重点实验室北京100876

针对满足差分隐私的高维数据发布问题,我们提出一种基于隐树模型的满足差分隐私的高维数据发布算法.该算法由隐变量生成、隐树结构学习、隐树参数学习和数据生成四个阶段组成.特别地,在该算法中,为了在对显变量进行分组并生成隐变量的... 详细信息

针对满足差分隐私的高维数据发布问题,我们提出一种基于隐树模型的满足差分隐私的高维数据发布算法.该算法由隐变量生成、隐树结构学习、隐树参数学习和数据生成四个阶段组成.特别地,在该算法中,为了在对显变量进行分组并生成隐变量的过程中保护隐私,我们提出一种满足差分隐私的隐变量生成方法.此外,为了在构建隐树的过程中保护隐私,我们提出了一种满足差分隐私的隐树模型结构学习方法.分析结果表明本文提出的算法满足ε-差分隐私.实验结果表明,与现有算法相比,所提出的算法可以获得更好的数据效用.

关键词：隐树模型高维数据发布差分隐私隐私保护

Shared p-cycles design for dual link failure restorability in optical WDM networks

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The Journal of china Universities of posts and telecommunications 2007年第3期14卷 74-78页

作者： XIE Zheng-cheng xing Jun-wei WU li JI Yue-feng Key Laboratory of Optical Communications and lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

pre-configured cycles （p-cycles） can attain high capacity efficiency and fast protection switching times in wavelength division multiplexing （WDM） networks. This article proposes the weighted straddling link algorithm（WSLA） for generating a {3.bset of all cycles that can guarantee 100% restorability in case of dual link failure, and give an integer linear programming（1Lp） formulation that solves the shared p-cycles design problem minimizing the total sp.r. capacities. Numerical re{3.lt shows that our method can achieve 100% dual link failure restorability with acceptable sp.r. capacity. The larger standard deviation of demand set and the larger node degree network, the better the shared p-cycles scheme p.r.orms.

关键词： dual link failure p-cycles WDM

research on Threshold Adjustment Algorithm in Adaptive Modulation and Coding

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The Journal of china Universities of posts and telecommunications 2006年第2期13卷 15-19页

作者： FAN Chen CHEN Mei-ya su li-jun YANG Da-cheng School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

Adaptive Modulation and Coding （AMC） has gained a lot of attentions in the research of High Speed Downlink packet Access （HSDpA）. The idea is to adapt the transmission to the fast changing channel conditions by the use of different Modulation and Coding Schemes （MCS）. This pap.r.presents an adaptive AMC algorithm and introduces a theoretical analysis model in order to to investigate its throughput and Frame Error rate （FEr）. subject to the given FEr target, our numerical and link level simulation results both show that our algorithm outp.r.orms other existing adaptive algorithms.

关键词： adaptive modulation and coding threshold adjust markov model HSDpA

基于惠更斯等效原理的高速高密度pCB分级建模方法

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电子学报 2024年第4期52卷 1118-1131页

作者：刘元安高兆栋孙胜苏明郑少勇吴帆郭星月穆冬梅北京邮电大学电子工程学院安全生产智能监控北京市重点实验室北京100876 电子科技大学电子科学与工程学院四川成都611731 中山大学电子与信息工程学院(微电子学院) 广东广州510006

当带宽达到20 GHz以上时(波长从15 mm到无穷小),高速高密度电子系统的内部电路电磁环境变得十分复杂,越来越难以建模和分析预测,进一步当带宽达到40 GHz以上时,电路电磁环境问题将变得更加尖锐.为在设计阶段能够对电磁作用过程、作用效... 详细信息

当带宽达到20 GHz以上时(波长从15 mm到无穷小),高速高密度电子系统的内部电路电磁环境变得十分复杂,越来越难以建模和分析预测,进一步当带宽达到40 GHz以上时,电路电磁环境问题将变得更加尖锐.为在设计阶段能够对电磁作用过程、作用效应进行预测评估及控制,需要精确的建模方法和针对大尺度问题的快速计算技术,尤其是超大带宽超高速混合电路和集成电路.本文提出了基于混合电路环境电磁计算基础理论的跨尺度处理技术,通过惠更斯等效原理和电磁奇异性几何结构的电磁收敛降速机理的利用,解决了多维交叉多尺度电路电磁环境场路融合的高效率高精度建模技术挑战;利用惠更斯等效原理和基尔霍夫积分方程,在区域边界面上定义了惠更斯端口,提出了对于任意复杂印制电路板(printed Circuit Board,pCB)同时垂直方向和水平方向区域分解的一般方法,实现了任意pCB结构的分级分类处理和模块化封装,提高了高速高密度电子系统分析的灵活度;提出了基于几何结构电磁学多重本地本征展开的技术途径,发展了基于模式和区域分解分割的快速并行处理技术,通过电磁锐变区域本征描述及场分布的本征基函数表征,实现了高精度和高计算速度兼得,减少了复杂电子系统的计算时间和设计时间.统计数据表明,本文提出的方法在0~40 GHz大带宽频率范围内频偏误差为3.7%、幅度偏差为±3.dB.本文提出的pCB分级建模分析方法可以应用于高端电子通信系统设计,提升我国宽带高速数模系统的高效电路设计和环境电磁调控能力,缩短产品研发周期.

关键词：等效原理本征模式展开电路建模区域分解信号完整性集成电路芯片封装

Multi-user diversity analysis in MISO amplify-and-forward relaying network

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The Journal of china Universities of posts and telecommunications 2010年第2期17卷 19-24页

作者： liU Fang cheng Jin-xing ZHANG Xin liANG Min CHEN Shao-hua YANG Da-cheng School of Nuclear Science and Engineering North China Electric Power University Beijing 102206 China School of Information and Communication Engineering Bcijing University of Posts and Telecommunications Beijing 100876 China No.8 qinghe Building Beijing 100085 China

This article analyzed multi-user diversity p.r.ormance for multiple input single output （MISO） amplify-and-forward （AF） relaying network with selection combiner, and the closed-form outage probabilities for variable gain relaying and fixed gain relaying network are derived. Based on these re{3.lts, diversity order is presented for variable gain relaying network. Simulation re{3.lts validate the derived theoretical re{3.lts, and the diversity order of variable gain relaying network with Nr available relays is K （Nt ＋ Nr） in K users＇ scenario, where Nt is the number of source transmitter antennas.

关键词： multi-user diversity amplify-and-forward MISO

Dark mode plasmonic optical microcavity biochemical sensor

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photonics research 2019年第8期7卷 939-947页

作者： cheng li LEI CHEN EUAN MCLEOD JUDITH su College of Optical Sciences University of ArizonaTucsonArizona85721USA State Key Laboratory of Information photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing100876China Dep.r.ment of Biomedical Engineering University of ArizonaTucsonArizona85721USA

Whisp.r.ng gallery mode(WGM) microtoroid optical resonators have been effectively used to sense low concentrations of biomolecules down to the single molecule limit. Optical WGM biochemical sensors such as the microtoroid op.r.te by tracking changes in resonant frequency as p.r.icles enter the evanescent near field of the ***, gold nanop.r.icles have been coupled to WGM resonators to increase the magnitude of resonance shifts via plasmonic enhancement of the electric field. However, this ap.r.ach results in increased scattering from the WGM, which degrades its quality(Q) factor, making it less sensitive to extremely small frequency shifts caused by small molecules or protein conformational changes. Here, we show using simulation that precisely positioned trimer gold nanostructures generate dark modes that sup.r.ss radiation loss and can achieve high (> 10~6) Q with an electric-field intensity enhancement of 43.0, which far exceeds that of a single rod(~2500 times). Through an overall evaluation of a combined enhancement factor, which includes the Q factor of the system, the sensitivity of the trimer system was improved 105× versus 84× for a single rod. Further simulations demonstrate that unlike a single rod system, the trimer is robust to orientation changes and has increased capture area. We also conduct stability tests to show that small positioning errors do not greatly impact the result.

关键词： WGM Dark mode plasmonic microcavity