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可对角化矩阵特征值分解扰动问题的快速求解方法

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湖南大学学报（自然科学版） 2024年第7期51卷 119-126页

作者：胡志祥杨其东黄潇贺文宇合肥工业大学土木与水利工程学院安徽合肥230009 安徽建筑大学土木工程学院安徽合肥230601

针对特征值扰动计算的传统方法收敛速度慢的问题,提出了一种求解特征值扰动问题的快速迭代算法.首先,通过矩阵变换将初始矩阵的特征值扰动问题转化为对角矩阵的特征值扰动问题.然后,提出了一种快速迭代算法求解扰动参数,同时对算法的收... 详细信息

针对特征值扰动计算的传统方法收敛速度慢的问题,提出了一种求解特征值扰动问题的快速迭代算法.首先,通过矩阵变换将初始矩阵的特征值扰动问题转化为对角矩阵的特征值扰动问题.然后,提出了一种快速迭代算法求解扰动参数,同时对算法的收敛性进行分析,并将其与基于摄动级数展开法导出的方法进行对比.再次,采用逐一求解特征值并进行矩阵降阶的策略,有效降低运算量.最后,通过2个算例分别展示算法的计算过程及其在结构模态参数追踪方面的应用效果.

关键词：特征值分解特征值扰动摄动级数展开法可对角化矩阵收敛性分析

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Noah-MP陆面模式对干旱区不同下垫面水热通量模拟评估

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沙漠与绿洲气象 2024年第1期18卷 28-37页

作者：杨扬杨启东中国气象局兰州干旱气象研究所甘肃兰州730020 云南大学地球科学学院大气科学系云南昆明650019

基于干旱区张掖国家气候观象台2021年1月-2022年6月和大满灌区绿洲农田站2020年1-12月的观测数据,评估Noah-MP模式对干旱区荒漠和农田两种下垫面的水热通量的模拟性能。结果表明:Noah-MP模式模拟的干旱区荒漠下垫面辐射与观测值的相关... 详细信息

基于干旱区张掖国家气候观象台2021年1月-2022年6月和大满灌区绿洲农田站2020年1-12月的观测数据,评估Noah-MP模式对干旱区荒漠和农田两种下垫面的水热通量的模拟性能。结果表明:Noah-MP模式模拟的干旱区荒漠下垫面辐射与观测值的相关系数均>0.98,泰勒评分>0.93。感热的泰勒评分(0.809)>潜热的泰勒评分(0.504),对辐射及湍流通量的变化特征、峰谷值与观测值总体一致,模拟效果较好。模拟的5 cm土壤湿度对降水过程有明显的响应,表现出明显的冷暖季差异,但其模拟性能仍有待改进。Noah-MP模式模拟的干旱区农田下垫面辐射通量及各层土壤温度的相关系数均>0.98,泰勒评分>0.58,模拟效果较理想。但模拟的潜热通量及各层土壤湿度较观测值偏低,尤其在生长季模拟性能不理想。Noah-MP模式对干旱区荒漠下垫面水热通量的模拟性能优于农田下垫面,优化和发展模式水文过程的参数化方案,在模式中考虑人为作用,是提高干旱区陆面过程模式模拟能力的重要方向。

关键词：干旱区 Noah-MP模式水热通量荒漠和农田下垫面

基于STM32微控制器的汽车仪表显示系统研究

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仪表技术 2024年第4期 67-70,73页

作者：杨启栋王淼河南机电职业学院河南郑州451191

以STM32F407微型控制器和控制器局域网络(CAN)总线通信技术为基础,致力于设计一款全液晶汽车仪表,以实现仪表与整车系统通过CAN总线网络节点的高效通信。采用CAN总线通信方式,元器件与控制元件(ECU)之间的信息传递更加可靠。根据新能源... 详细信息

以STM32F407微型控制器和控制器局域网络(CAN)总线通信技术为基础,致力于设计一款全液晶汽车仪表,以实现仪表与整车系统通过CAN总线网络节点的高效通信。采用CAN总线通信方式,元器件与控制元件(ECU)之间的信息传递更加可靠。根据新能源汽车仪表的功能需求,对整车系统应用层进行明确定义,进行了总体结构的硬件与软件设计。对该系统进行测试和分析,结果表明该设计不仅提供了更简单的接线方式,还实现了模块间的快速通信,同时具备全液晶显示的优势。

关键词：微控制器控制器局域网络总线汽车仪表

WRF模式多参数化方案对东南亚低纬高原陆气耦合强度的模拟评估

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高原气象 2024年第4期43卷 995-1010页

作者：王秀智杨启东何帅辰石紫琳吕柄溶云南大学地球科学学院大气科学系云南昆明650091 云南省大湄公河次区域气象灾害与气候资源重点实验室云南昆明650091

东南亚低纬高原是全球陆气耦合的热点地区之一,其陆气相互作用对气候、水文和环境均具有重要的影响。本研究采用均匀抽样方法,结合WRF模式中多参数化方案,开展了48组数值模拟试验,通过优选参数化方案组合,对该地区陆气耦合强度及其相关... 详细信息

东南亚低纬高原是全球陆气耦合的热点地区之一,其陆气相互作用对气候、水文和环境均具有重要的影响。本研究采用均匀抽样方法,结合WRF模式中多参数化方案,开展了48组数值模拟试验,通过优选参数化方案组合,对该地区陆气耦合强度及其相关变量进行了模拟评估。研究表明:(1)从48组模拟试验集合中可发现,对于近地面或地表的气温、比湿、向下长波、向上长波和土壤温度,集合模拟能力较好;对于近地面或地表的风速、降水、感热通量、潜热通量、向下短波和向上短波,集合模拟可较好反映各变量的变化特征;但是对于地表的土壤湿度,集合模拟能力较差。对于近地面或地表的风速、降水、潜热通量、向下短波、向上短波、土壤温度和土壤湿度,不同组合间模拟差异较小;但是对于地表的感热通量,不同组合间模拟差异较大。(2)根据等权重平均Taylor评分获得的最优参数化方案组合可以提升对于近地面或地表的气温、比湿、向下短波、向上短波、向下长波、向上长波和土壤温度的模拟能力,但对于近地面或地表的风速、降水、感热通量、潜热通量和表层土壤湿度提升效果不明显。(3)最优参数化方案组合可以合理地反映陆气耦合的空间特征和时间变化,但模拟的耦合强度较参考值偏弱,主要与潜热通量和向下短波辐射模拟能力较差有关。

关键词：陆气耦合 WRF模式东南亚低纬高原均匀抽样方法

Susceptibility gene for stroke or cerebral infarction in the Han population in Hunan Province of China

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Neural Regeneration Research 2013年第16期8卷 1519-1527页

作者： Danheng Mo Hongwei Xu Wensheng Zhou Qiming yang Jianwen yang Bo Xiao qidong yang Department of Neurology Hunan Provincial Mawangdui Hospital Department of Neurology Xiangya Hospital Central South University

The scavenger receptor class B type I gene can protect against atherosclerosis; a mononucleotide polymorphism is associated with differences in blood lipid metabolism, postprandial serum lipid levels, insulin resistance, coronary artery disease and familial hyperlipidemia. In this study, the scavenger receptor class B type I gene exon 1 G4A gene polymorphism in atherosclerotic cerebral infarction patients, cerebral hemorrhage patients and normal controls was detected using the polymerase chain reaction-restriction fragment length polymorphism method. The results showed that the GA ＋ AA genotype frequency of scavenger receptor class B type I gene G4A in atherosclerotic cerebral infarction patients was similar to that in cerebral hemorrhage patients and normal controls; however, the A allele frequency was significantly lower than that in normal controls. The serum level of high-density lipoprotein cholesterol in patients with the scavenger receptor class B type I gene G4A GA ＋ AA genotype was significantly higher, while the serum level of low-density lipoprotein cholesterol was significantly lower than that in patients with the GG genotype, in both the atherosclerotic cerebral infarction and cerebral hemorrhage groups. The serum level of high-density lipoprotein cholesterol in patients with the scavenger receptor class B type I gene G4A GA ＋ AA genotype was significantly higher, while the serum levels of low-density lipoprotein cholesterol and total cholesterol were significantly lower than those in normal controls with the GG genotype. Our experimental results suggest that the G4A polymorphism of the scavenger receptor class B type I gene is a possible predisposing risk factor for atherosclerotic cerebral infarction, and that it has no association with cerebral hemorrhage in the Hart population in Hunan province of China. The A allele is possibly associated with the metabolism of high-density and low-density lipoprotein cholesterol.

关键词： neural regeneration scavenger receptor class B type I stroke atherosclerotic cerebral infarction cerebral hemorrhage genetic polymorphism cholesterol neuroregeneration

Electrical fields and the promotion of endogenous angiogenesis in a rat spinal cord injury model

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Neural Regeneration Research 2010年第14期5卷 1091-1095页

作者： yang Shao Bo Xiao Haihan Ma Jie Gao qidong yang Min Zhao Department of Neurology Xiangya Hospital Central South University Changsha 410008 Hunan Province China State Key Laboratory of Trauma Burns and Combined Injury Institute of Surgery Research Daping Hospital Third Military Medical University Chongqing 400042 China School of Medical Sciences University of Aberdeen Aberdeen AB25 2ZD UK

BACKGROUND： Previous studies have shown that direct current electrical fields affect development and growth of human microvascular endothelial cells, but the role of electrical fields on promoting angiogenesis in tissues following spinal cord injury remains poorly understood. OBJECTIVE： To determine the effects of electrical fields on angiogenesis and spinal cord repair following traumatic spinal cord injury in rats. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Chongqing Key Laboratory of Neurology, Affiliated Hospital of Chongqing Medical University, China from September 2007 to August 2008. MATERIALS： Hydrogen blood flow detector （Soochow University Medical Instrument, China）, Power Lab System （AD Instruments, Colorado Springs, CO, USA） and mouse anti-vascular endothelial growth factor （VEGF） monoclonal antibody （Sigma-Aldrich, St. Louis, MO, USA） were used in this study. METHODS： A total of 60 healthy, adult, Sprague Dawley rats were equally and randomly assigned to sham-surgery, model, and electrical field groups. The Allen＇s weight-drop method was used to induce complete spinal cord injury in the model and electrical field groups. Rats in the electrical field group were implanted with silver needles and electrical fields （350 V/m） were applied following traumatic injury. MAIN OUTCOME MEASURES： Latency of somatosensory-evoked potential was detected and spinal cord blood flow was measured by hydrogen blood flow detector. Microvascular density was determined by histological analysis. VEGF expression in the spinal cord was observed by immunohistochemical staining. RESULTS： Recovery of spinal cord blood flow was significantly increased in the electrical field group （at 1, 2, 4, 8, and 24 days after injury） compared with the model group （P 〈 0.05 or P 〈 0.01）. Latency of P1 waves in somatosensory-evoked potential of electrical field group （at 1,2, 4, 8, and 24 days after injury） was significantly shorter than the

关键词： angiogenesis electric fields spinal cord injury spinal cord blood flow vascular endothelial growth factor neural regeneration

基于液冷技术的高性能计算系统助力实现“双碳”目标的研究与实践

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现代工业经济和信息化 2024年第5期14卷 71-72,84页

作者：沈学东王军张墨涵杨启东王琨北京临近空间飞行器系统工程研究所北京100076

碳达峰碳中和是我国实现可持续发展、高质量发展的内在要求,已多次被写入政府工作报告,报告中提及要促进新能源节能环保技术、装备和产品研发应用,培育壮大节能环保产业。高性能计算系统作为航天领域重要的科研生产研制工具,一直面临着... 详细信息

碳达峰碳中和是我国实现可持续发展、高质量发展的内在要求,已多次被写入政府工作报告,报告中提及要促进新能源节能环保技术、装备和产品研发应用,培育壮大节能环保产业。高性能计算系统作为航天领域重要的科研生产研制工具,一直面临着高能耗和高散热的挑战。通过对高性能计算系统冷却系统现状分析,提出基于液冷技术的高性能计算系统的解决方案,通过降低PUE值,推动高性能计算系统低碳运转,打造具备绿色节能特点的高性能计算中心,助力“双碳”目标实现。

关键词：液冷碳达峰碳中和高性能计算环保节能

Neuroprotective role of edaravone and the effects of endoplasmic reticulum stress in an adult rat model of focal cerebral ischemia/reperfusion

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Neural Regeneration Research 2010年第3期5卷 197-204页

作者： Xiangmin Shen Liming Tan Yunhai Liu Hainan Zhang Chunyu Wang qidong yang QingHuang Lin Zhou Zhenyu Tang Department of Neurology Xiangya Hospital Central South University Changsha 410008 Hunan Province China Department of Neurology Second Xiangya Hospital Central South University Changsha 410011 Hunan Province China

BACKGROUND： Endoplasmic reticulum （ER） stress impairs ER functions and leads to the accumulation of unfolded or misfolded proteins in the ER lumen. ER stress-induced cell death plays an important role in cerebral ischemia. Edaravon （3-methyl-1-phenyl-2-pyrazolin-5-one） is a potent and novel scavenger of free radicals that inhibit delayed neuronal death, as demonstrated by in vitro and animal studies. However, its effect on ER stress and induced neuronal apoptosis in a rat model of brief middle cerebral artery occlusion remains unclear. OBJECTIVE： To explore the effects of edaravone on the expression of ER stress-related factors and neuronal apoptosis, based on the hypothesis that edaravone influences ER stress in a rat model of cerebral ischemia/reperfusion. DESIGN, TIME AND SETTING： A randomized, controlled, animal study was performed at the Laboratory of Department of Neurology, Xiangya Hospital and the Department of Laboratory Animals, Xiangya Medical College, Central South University in China from June 2005 to May 2006. MATERIALS： Edaravone was purchased from Simcere Pharmaceutical Group, China. METHODS： A total of 216 adult, male, Sprague Dawley rats were randomly assigned to sham-surgery, model and edaravone groups, with 72 rats in each group, Brief middle cerebral artery occlusion was established in the model and edaravone groups. In addition, the edaravone group rats were injected with 3 mg/kg edaravone through the tail vein. MAIN OUTCOME MEASURES： RNA-dependent protein kinase-like endoplasmic reticulum eukaryotic translation initiation factor 2a kinase （PERK） and C/EBP homology protein （CHOP） mRNA expression in the ischemic parietal cortex was determined by reverse transcriptionpolymerase chain reaction; phosphorylated PERK and CHOP protein expression was detected by immunohistochemistry; neuronal apoptosis was detected by TdT-mediated-dUTP nick end labeling. RESULTS： Neurological deficit scores were significantly reduced in the edaravone group compared to

关键词： edaravone cerebral ischemia/reperfusion endoplasmic reticulum stress RNA-dependent protein kinase-like endoplasmic reticulum elF2a kinase C/EBP homology protein brain injury neural regeneration

Traffic Prediction Method for GEO Satellites Combining ARIMA Model and Grey Model

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Journal of Shanghai Jiaotong university(Science) 2020年第1期25卷 65-69页

作者： ZHOU Jian yang qidong ZHANG Xiaofei HAN Chong SUN Lijuan College of Computer Jiangsu High Technology Research Key Laboratory for Wireless Sensor NetworksNanjing University of Posts and TelecommunicationsNanjing 210023China

An accurate traffle prediction on various service is of great importance to the channel resource management of geostationary earth orbit(GEO)***,a traffic prediction method for GEO satellites combining autoregressive integrated moving average(ARIMA)model and grey model is ***,the traffle prediction methods based on ARIMA model and grey model are introduced ***,a combined model is given,in which according to the results of the historical prediction of ARIMA model and grey model,those two models are combined with different ***,the combined model is applied to a multi-service access and the access probability of each kind of service is calculated based on the prediction ***,the simulation experiments indicate that the combined model has better prediction stability and higher average prediction accuracy than either of the separated ***,the proposed access strategy based on the combined model performs better than other similar strategies.

关键词： traffic prediction ARIMA model grey model access GEO satellites