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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 16-21页

作者： yan sheng-nan LI yan College of Information Science and Engineering Yanshan University School of Information and Communication Engineering Beijing University of Posts and Telecommunications

This paper investigates the performance of an underlay cognitive relay system where secondary users（SUs） suffer from a primary outage probability constraint and spectrum-sharing interference imposed by a primary user（PU）. In particular, we consider a secondary multi-relay network operating in the selection decode-and-forward（SDF） mode and propose a best-relay selection criterion which takes into account the spectrum-sharing constraint and interference. Based on these assumptions, the closed-form expression of the outage probability of secondary transmissions is derived. We find that a floor of the outage probability occurs in high signal-to-noise ratio（SNR） regions due to the joint effect of the constraint and the interference from the PU. In addition, we propose a generalized definition of the diversity gain for such systems and show that a full diversity order is achieved. Simulation results verify our theoretical solutions.

关键词： cognitive relay systems spectrum-sharing interference outage probability diversity gain

Dissecting the genetic basis of grain color and pre-harvest sprouting resistance in common wheat by association analysis

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Journal of Integrative Agriculture 2023年第9期22卷 2617-2631页

作者： yan sheng-nan YU Zhao-yu GAO Wei WANG Xu-yang CAO Jia-jia LU Jie MA Chuan-xi CHANG Cheng ZHANG Hai-ping Key Laboratory of Wheat Biology and Genetic Improvement on Southern Yellow&Huai River Valley Ministry of Agriculture and Rural Affairs/College of AgronomyAnhui Agricultural UniversityHefei 230036P.R.China

Pre-harvest sprouting(PHS) adversely affects wheat quality and yield, and grain color(GC) is associated with PHS resistance. However, the genetic relationship between GC and PHS resistance remains unclear. In this study, 168 wheat varieties(lines) with significant differences in GC and PHS resistance were genotyped using an Illumina 90K iSelect SNP array. Genome-wide association study(GWAS) based on a mixed linear model showed that 67 marker-trait associations(MTAs) assigned to 29 loci, including 17 potentially novel loci, were significantly associated with GC, which explained 1.1–17.0% of the phenotypic variation. In addition, 100 MTAs belonging to 54 loci, including 31 novel loci, were significantly associated with PHS resistance, which accounted for 1.1–14.7% of the phenotypic variation. Subsequently, two cleaved amplified polymorphic sequences(CAPS) markers, 2B-448 on chromosome 2B and 5B-301 on chromosome 5B,were developed from the representative SNPs of the major common loci ***-2B.3/***-2B.4controlling GC/PHS resistance and PHS resistance locus ***-5B.4, respectively. Further validation in 171 Chinese mini-core collections confirmed significant correlations of the two CAPS markers with GC and PHS resistance phenotypes under different environments(Pnant inbred lines(RILs) constructed based on specific locus amplified fragment sequencing markers showed that CAPS-356 collocated with a novel QTL for PHS resistance, supporting the role of TraesCS5B02G545100 as the potential candidate gene linked to ***-5B.4. These r

关键词： common wheat grain color PHS resistance GWAS 90K SNP CAPS marker

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感知中继网络中依据检测结果的频谱共享机制

北京邮电大学学报 2010年第5期33卷 41-46页

作者：闫盛楠王晓湘泛网无线通信教育部重点实验室(北京邮电大学) 北京100876

在感知中继网络中,为实现授权频带在主次用户间的高效利用,提出一种基于检测结果的频谱共享机制,允许次用户根据频谱检测的结果自适应地选择传输方式.并在该机制下,考虑主次用户间的干扰情况,进而根据信干噪比(SINR)推导出次用户网络的... 详细信息

在感知中继网络中,为实现授权频带在主次用户间的高效利用,提出一种基于检测结果的频谱共享机制,允许次用户根据频谱检测的结果自适应地选择传输方式.并在该机制下,考虑主次用户间的干扰情况,进而根据信干噪比(SINR)推导出次用户网络的中断概率和符号错误概率的闭式表达式.仿真结果表明,本机制与传统的频谱共享机制相比,能在保证主用户通信的前提下,使次用户网络获得较高的性能增益.

关键词：感知中继网络频谱共享中断概率符号错误概率

股价特质性波动视角下我国是否应放开回转交易制度?——基于A/B股分行业的准自然实验证据

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东北大学学报（社会科学版） 2020年第1期22卷 22-30页

作者：李竹薇付媛颜胜男大连理工大学经济管理学院

选取我国A/B股总体和分行业的两阶段日数据作为准自然实验的样本数据,采用Fama-French五因子模型和DMYZ模型衡量股价特质性波动并构建双重差分模型,研究回转交易制度变更对股价特质性波动的影响作用,探求我国是否应全面放开回转交易制... 详细信息

选取我国A/B股总体和分行业的两阶段日数据作为准自然实验的样本数据,采用Fama-French五因子模型和DMYZ模型衡量股价特质性波动并构建双重差分模型,研究回转交易制度变更对股价特质性波动的影响作用,探求我国是否应全面放开回转交易制度。研究结果表明:总体上,在T+0回转交易制度下A股的股价特质性波动明显小于B股,但在T+1回转交易制度下A股和B股特质性波动相差不大;T+0回转交易制度提高了股价特质性波动,而T+1回转交易制度降低了股价特质性波动;分行业研究发现,除交通、信息、租赁行业不敏感之外,其余行业对不同回转交易制度的反应与总体一致。因此,出于稳定市场考虑,不建议我国现阶段全面开放回转交易制度,但可以A股市场的蓝筹股为试点,在股市整体进一步成熟稳定后再考虑逐步放开回转交易使其与国际制度接轨。

关键词：回转交易制度股价特质性波动准自然实验双重差分模型 Fama-French五因子模型

Boosting cationic and anionic redox activity of Li-rich layered oxide cathodes via Li/Ni disordered regulation

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Journal of Energy Chemistry 2025年第1期100卷 533-543页

作者： Zewen Liu Zhen Wu Hao Wang Xudong Zhang Yuanzhen Chen Yongning Liu shengwu Guo shenghua Chen yanli nan yan Liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University School of Materials Science and Engineering Xi'an University of Architecture and Technology Hefei Advanced Computing Center Operation Management Corp Ltd Network Information Center Xi'an Jiaotong University

Lithium-rich layered oxides （LLOs） are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries （LIBs）.However,they suffer from voltage decay and low initial Coulombic efficiency （ICE） due to severe structural degradation caused by irreversible O ***,we introduce a three-in-one strategy of increasing Ni and Mn content,along with Li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of *** target material,Li1.2Ni0.168Mn0.558Co0.074O2（L1）,exhibits an improved ICE of 87.2%and specific capacity of 293.2 mA h g-1and minimal voltage decay of less than 0.53 m V cycle-1over 300 cycles at 1C,compared to Li1.2Ni0.13Mn0.54Co0.13O2（Ls）(274.4 mA h g-1for initial capacity,73.8%for ICE and voltage decay of 0.84 mV/cycle over 300 cycles at 1C).Theoretical calculations reveal that the density of states （DOS） area near the Fermi energy level for L1 is larger than that of Ls,indicating higher anionic and cationic redox reactivity than ***,L1 exhibits increased O-vacancy formation energy due to higher Li/Ni disordering of 4.76%（quantified by X-ray diffraction Rietveld refinement） and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical *** increased Li/Ni disordering also leads to more Ni2+presence in the Li layer,which acts as a pillar during Li+de-embedding,improving structural *** research not only presents a viable approach to designing low-Co LLOs with enhanced capacity and ICE but also contributes significantly to the fundamental understanding of structural regulation in high-performance LIB cathodes.

关键词： Ice

基于人工神经网络模型的非球形颗粒曳力系数预测

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工程热物理学报 2017年第10期38卷 2171-2175页

作者：闫盛楠唐天琪任安星何玉荣哈尔滨工业大学能源科学与工程学院哈尔滨150001

本文通过人工神经网络预测方法对非球形颗粒气固曳力系数进行了预测及分析。首先比较了BP(Backpropagation)神经网络模型和RBF(Radical Basis Function)基神经网络模型对Pettyjohn和Christiansen等人实验工况中的结果进行了预测。结果表... 详细信息

本文通过人工神经网络预测方法对非球形颗粒气固曳力系数进行了预测及分析。首先比较了BP(Backpropagation)神经网络模型和RBF(Radical Basis Function)基神经网络模型对Pettyjohn和Christiansen等人实验工况中的结果进行了预测。结果表明,采用RBF方法预测非球形颗粒气固曳力系数误差较小,计算效率较高。同时,应用RBF基神经网络模型,对不同形状因子下的气固曳力系数进行了预测和分析。研究结果表明,人工神经网络可以用于非球形颗粒气固曳力系数的预测研究,本文研究结果为复杂形状颗粒气固曳力系数的预测提供了一种有效的手段。

关键词：人工神经网络非球形颗粒曳力系数

Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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nano-Micro Letters 2025年第3期17卷 340-354页

作者： Li An Jianyi Li Yuanmiao Sun Jiamin Zhu Justin Zhu Yeow Seow Hong Zhang nan Zhang Pinxian Xi * Zhichuan JXu Chun‑Hua yan State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceFrontiers Science Center for Rare IsotopesCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000People’s Republic of China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Faculty of Materials Science and Energy Engineering Institute of Technology for Carbon NeutralityShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Key Laboratory of Electromagnetic Materials and Devices National Center for International Research On Photoelectric and Energy MaterialsSchool of Materials and EnergyElectron Microscopy CenterYunnan UniversityKunming 650091People’s Republic of China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030People’s Republic of China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU‑HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryPeking UniversityBeijing 100871People’s Republic of China

Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution *** surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity ***,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is *** substituting Fe content influences both current change tendency and surface reconstruction ***_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)*** reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based ***,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term ***,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction *** effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface *** finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction Perovskite oxides Doping Activation and reconstruction

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基于方向密度检测与霍夫变换的混合矩阵估计

北京理工大学学报 2016年第11期36卷 1188-1193页

作者：孙洁娣李玉霞温江涛闫盛楠燕山大学信息科学与工程学院河北秦皇岛066004 燕山大学河北省测试计量技术及仪器重点实验室河北秦皇岛066004

针对欠定盲源分离混合矩阵的估计问题,提出一种基于局部方向密度检测的孤立时频点处理与霍夫变换相结合的混合矩阵估计算法.首先通过变换域单源时频点处理增强信号的稀疏性,对散点图中的方向直线进行霍夫变换,通过判断局部极大值点确定... 详细信息

针对欠定盲源分离混合矩阵的估计问题,提出一种基于局部方向密度检测的孤立时频点处理与霍夫变换相结合的混合矩阵估计算法.首先通过变换域单源时频点处理增强信号的稀疏性,对散点图中的方向直线进行霍夫变换,通过判断局部极大值点确定源信号数量并估计混合矩阵.针对霍夫变换易出现的峰值簇拥问题,提出采用局部方向密度检测方法先判别并去除孤立时频点,之后再进行霍夫变换,提高了混合矩阵的估计精度.实验结果表明本文所提出的方法能够在未知源信号数量情况下实现混合矩阵估计,且估计精度高于K-means等常用方法.

关键词：欠定盲源分离混合矩阵估计霍夫变换局部方向密度孤立时频点

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基于PSCAD双馈风力发电机励磁控制研究

科技信息 2012年第31期 439-440,447页

作者：闫胜男呼和浩特供电局内蒙古呼和浩特010050

在能源短缺和环境污染日益严重的今天,作为可再生绿色能源的风能的开发利用具有十分重要的意义。本文以交流励磁变速恒频风力发电系统的运行与控制为主题,进行了从理论到仿真的全面、深入的研究。对DFIG(双馈型感应发电机)的并网运行理... 详细信息

在能源短缺和环境污染日益严重的今天,作为可再生绿色能源的风能的开发利用具有十分重要的意义。本文以交流励磁变速恒频风力发电系统的运行与控制为主题,进行了从理论到仿真的全面、深入的研究。对DFIG(双馈型感应发电机)的并网运行理论、最大风能追踪机理、DFIG有功无功功率解耦控制、双PWM型变换器特性等方面进行了细致的研究,获得了一些重要结论和具有创新意义的成果。

关键词：双馈感应发电机变速恒频并网运行

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang nan Zheng Qingming Lin yan You Zheng Gong yangping Zhuang Jiali Wu Yu Wang Hanlin Huang Jun Ke Feng Chen shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species