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DOA Estimation Using Block Variational Sparse Bayesian Learning

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Chinese Journal of Electronics 2017年第4期26卷 768-772页

作者： HUANG Qinghua zhang guangfei FANG Yong Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University

In Direction-of-arrival(DOA) estimation,the real-valued sparse Bayesian algorithm degrades the estimation performance by decomposing the complex value into real and imaginary components and combining them independently. We directly use complex probability density functions to model the noise and complex-valued sparse direction weights. Based on the Multiple measurement vectors(MMV), block sparse structure for the direction weights is integrated into the variational Bayesian learning to provide accurate source direction estimates. The proposed algorithm can be used for arbitrary array geometries and does not need the prior information of the incident signal number. Simulation results demonstrate the better performance of the proposed method compared with the real-valued sparse Bayesian algorithm, the Orthogonal matching pursuit(OMP) and l1 norm based complexvalued methods.

关键词： Direction-of-arrival estimation Varia tional Bayesian learning Sparse recovery Multiple mea surement vectors Block sparse structure

Near-Field Source Localization Using Spherical Microphone Arrays

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Chinese Journal of Electronics 2016年第1期25卷 159-166页

作者： HUANG Qinghua zhang guangfei LIU Kai Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University

A new method is proposed for joint range and bearing(azimuth and elevation) estimation of multiple near-field acoustic sources using observations collected by a spherical microphone array. First, Spherical Fourier transform(SFT) is used to construct the array signal model in the spherical harmonics domain to decouple range and bearing information. Then the relation among the spherical harmonics of three adjacent degrees is exploited to build the recursive relationship of the signal subspace. Using Eigenvalue decomposition(EVD), bearings are estimated based on the eigenvalues and simultaneously the steering matrix can be represented by the signal ***, range is estimated using the energy ratios of the elements of the steering matrix in the spherical harmonics domain. The algorithm can avoid parameter pairing and multi-dimensional searching. It has lower computational complexity than that of the Multiple signal classification(MUSIC) method. The performance is evaluated by Monte-Carlo simulations and the estimation root meansquare errors are compared to the corresponding CramerRao bounds(CRBs) and those of MUSIC range estimates,which demonstrate the validity of the proposed algorithm.

关键词： Spherical microphone array Source localization Near-field Spherical Fourier transform(SFT) Spherical harmonics

Design and experiment analysis of the small maize harvester with attitude adjustment in the hilly and mountainous areas of China

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 118-127页

作者： Meizhou Chen guangfei Xu Yuanzhen Wei Yinping zhang Peisong Diao Huanxiao Pang College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo255000ShandongChina School of Mechanical and Automotive Engineering Liaocheng UniversityLiaocheng252000ShandongChina Shandong Academy of Agricultural Machinery Sciences Jinan 250000China

To solve the problem of small planting plots and large sloping land for mechanized maize harvesting in China hilly and mountainous areas,a small maize harvester with attitude adjustment was designed to realize maize snapping,peeling,straw crushing and attitude adjusting at on time in this *** basic structure and working principle of the small maize harvester were described,and the key components were designed as *** maize snapping device adopted the combination form of maize snapping plates and straw pulling rollers,and the gap of the straw pulling rollers can be adjusted to adapt to different maize *** pairs of peeling rollers formed a groove arrangement to improve peeling rate and reduced ear grain *** pressure feeding device mainly comprised drive chain and three grade pressure feeding rollers to increase the friction between ears and the peeling rollers,and help ears *** attitude adjustment advice was designed according to the high point stationary pursuit leveling *** the attitude angle of the rack approached 0,the small maize harvester reached the level *** actual range of attitude adjustment was obtained and the accuracy of static attitude adjustment was verified through attitude adjustment *** influencing factors of ear loss rate and bract peeling rate were determined by orthogonal test,including the rotational speed of straw pulling rollers,peeling rollers and pressure feeding *** mathematical regression model between the experimental factors and indicators was established by using Design Expert,and through the analysis variance to verify the significance of the evaluation indicators,the best combination of operation parameters was determined that the rotational speed of straw pulling rollers,peeling rollers and pressure feeding rollers were 1440 r/min,1535 r/min and 406 r/*** the optimal combination of the operation parameters,the ear loss rate and bract peeling rate were 1.33%and 93.98%.T

关键词： maize harvester hilly and mountains areas attitude adjustment anti rollover structure

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浅谈高职院校英语专业教学中的美育策略

英语教师 2022年第22期22卷 16-18页

作者：张光妃广东茂名幼儿师范专科学校广东茂名525000

在简要介绍美育重要性的基础上,分析高职院校英语专业教学中的美育现状。提出深入感知语言之美、开展基于主题的思辨、采用多元化的教学方法等高职院校英语专业教学中的美育策略。认为高职院校英语专业教学中的美育应以语言学习为基础,... 详细信息

在简要介绍美育重要性的基础上,分析高职院校英语专业教学中的美育现状。提出深入感知语言之美、开展基于主题的思辨、采用多元化的教学方法等高职院校英语专业教学中的美育策略。认为高职院校英语专业教学中的美育应以语言学习为基础,以课程内容为依托,注重感知与思辨,助力学生获得审美体验,在感知、思辨中拓展思维,锤炼品质,实现全面发展。

关键词：高职院校英语专业美育

Seasonal Dynamics of the Soil Moisture in Yuanmou Dry-Hot Valley of Yunnan

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Meteorological and Environmental Research 2013年第4期4卷 56-58页

作者： Yuanjiao Zhao Wenhua Su guangfei zhang Fengtao Cui Rui Zhou Institute of Ecology and Geobotany Yunnan University

[ Objective] The research aimed to study seasonal dynamics of the soil moisture in Yuanmou Dry-Hot Valley of Yunnan. [ Method] We investigated soil moisture in rainy season in Yuanmou Dry-Hot Valley. By combining completed research about soil moisture in dry season, data in rainy and dry seasons were contrasted to study seasonal dynamics of the soil moisture in the zone. [ Resultl Soil moisture in rainy season increased with the depth of soil, but would decrease within 1.0 m below the root layer. The soil moisture of grassland was higher than that of the woodland, while soil moisture of the savanna was higher than that of the woodland but lower than that of the grassland. In addition, compared with soil mois- ture in dry season, it is clear that to avoid forming permanent soil desiccation, based on soil and hydrology conditions in Yuanmou, it is better to plant grass not tree in Yuanmou when we do something about ecological restoration. [ Condusion] The research had certain guidance significance for planting agricultural and economic crops and carrying out ecological restoration in Yuanmou Dry-Hot Valley.

关键词： Dry-Hot Valley Seasonal dynamics Soil moisture content Soil desiccation China

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中国西南四种常见松树火适应性状比较

生态学报 2023年第3期43卷 1064-1072页

作者：苏文华司宏敏张辉红张光飞周睿郭晓荣杨琼云南大学生态学与地植物学研究所昆明650091 云南大学生态与环境学院昆明650091

野火对松属植物的进化和分布有重要的影响。在与野火长期抗争中,松属植物形成了一系列性状提高在易火生境中的适合度,维持种群生存与繁衍。西南地区是中国野火高发区,作为这一地区特有松树,云南松、思茅松和高山松具有一些典型的火适应... 详细信息

野火对松属植物的进化和分布有重要的影响。在与野火长期抗争中,松属植物形成了一系列性状提高在易火生境中的适合度,维持种群生存与繁衍。西南地区是中国野火高发区,作为这一地区特有松树,云南松、思茅松和高山松具有一些典型的火适应性状,如厚树皮。以这3种松树和东部常见的马尾松为研究对象,比较4种松树的火适应对策。结果表明:4种松树的火适应性状存在一定的差异。与火适应相关的13项性状主成分分析显示,4个种在空间上总体是分离的,也表现出一些重叠。其中云南松火适应生活史对策是火耐受型和火依赖型的中间类型,适应会发生林冠火的生境。高山松、思茅松和马尾松都是火耐受型,通过快速高生长、厚树皮等性状适应生境不同频度的地表火。四种松树火适应对策与分布区火险基本相符。表明野火在这一区域广泛存在,并对植物进化和森林格局有重要影响。野火在西南地区松属分布和种群维持中的生态作用应被给予足够重视。

关键词：松树火适应对策生态分化分布格局中国西南

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GAT-EGRU:A Deep Learning Prediction Model for PM2.5 Coupled with Empirical Modal Decomposition Algorithm

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Journal of Systems Science and Systems Engineering 2023年第2期32卷 246-263页

作者： guangfei Yang Qiang zhang Erbiao Yuan Liankui zhang School of Economics and Management Dalian University of TechnologyDalian116024China School of Environmental Science and Technology Dalian University of TechnologyDalian116024China

With the rapid development of the economy and industry and the improvement of pollution monitoring,how to accurately predict PM2.5 has become an issue of concern to the government and *** the field of PM2.5 pollution forecasting,a series of results have emerged so ***,in the existing research field of PM2.5 prediction,most studies tend to predict short-term temporal *** studies tend to ignore the temporal and spatial characteristics of PM2.5 transport,which leads to its poor performance in long-term *** this paper,by optimizing previous PM2.5 deep learning prediction models,we propose a model ***,we add a spatial modular Graph Attention Network(GAT)and couple an Empirical Modal Decomposition algorithm(EMD),considering the temporal and spatial properties of ***,we use Gated Recurrent Unit(GRU)to filter spatio-temporal features for iterative rolling PM2.5 *** experimental results show that the GAT-EGRU model has more advantages in predicting PM2.5 concentrations,especially for long time *** proves that the GAT-EGRU model outperforms other models for PM2.5 *** that,we verify the effectiveness of each module by distillation *** experimental results show that each model module has an essential role in the final PM2.5 prediction *** new model improves the ability to predict PM2.5 after a long time accurately and can be used as a practical tool for predicting PM2.5 concentrations.

关键词： Air pollution forecasting deep learning spatial-temporal prediction empirical modal decomposition

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高性能多媒体SoC分组访存调度算法

计算机辅助设计与图形学学报 2011年第9期23卷 1585-1592页

作者：张广飞汪文祥蒋毅飞苏孟豪中国科学院计算机系统结构重点实验室北京100190 中国科学院计算技术研究所北京100190 中国科学院研究生院北京100049 北京龙芯中科技术服务中心有限公司北京100190

根据多媒体处理单元的访存特点,提出一种面向高性能多媒体SoC的分组访存调度算法.该算法将访存请求按照访存ID和页地址分组,以访存组为单位进行乱序调度,并通过维护相同ID访存请求之间的顺序保证访存的正确性:综合考虑访存单元的访存效... 详细信息

根据多媒体处理单元的访存特点,提出一种面向高性能多媒体SoC的分组访存调度算法.该算法将访存请求按照访存ID和页地址分组,以访存组为单位进行乱序调度,并通过维护相同ID访存请求之间的顺序保证访存的正确性:综合考虑访存单元的访存效率和服务质量要求,在每个访存单元独立的调度周期内提供最低带宽保障服务.将该分组访存调度算法应用于访存调度装置,实际应用仿真结果表明,与已有基于带宽分配的访存调度算法相比,文中算法在保障访存单元带宽需求的同时降低了访存延迟,并将平均带宽利用率提高了15%.

关键词：访存调度多媒体片上系统 SDRAM

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土壤水分胁迫对短葶飞蓬有效成分含量的影响

中国中药杂志 2009年第10期34卷 1191-1194页

作者：张亚妮苏文华张光飞云南大学生态学与地植物学研究所云南昆明650091

目的:研究土壤水分胁迫对短葶飞蓬灯盏乙素和咖啡酸酯含量的影响,验证逆境效应理论。方法:测定8%,15%,23%3个水分梯度下短葶飞蓬植株PSⅡ的最大光化学效率(Fv/Fm),氮含量、灯盏乙素和咖啡酸酯含量。结果和结论:8%,23%含水量组的短葶飞... 详细信息

目的:研究土壤水分胁迫对短葶飞蓬灯盏乙素和咖啡酸酯含量的影响,验证逆境效应理论。方法:测定8%,15%,23%3个水分梯度下短葶飞蓬植株PSⅡ的最大光化学效率(Fv/Fm),氮含量、灯盏乙素和咖啡酸酯含量。结果和结论:8%,23%含水量组的短葶飞蓬植株Fv/Fm明显低于15%正常水处理组,分别构成轻度干旱和水涝胁迫。2种水分胁迫条件下,短葶飞蓬氮含量低于正常处理组,而有效成分却显著高于正常水处理组。水分胁迫促进了短葶飞蓬药用成分的积累,结果支持环境诱导次生代谢产物合成积累的"碳素/营养平衡假说"和道地药材形成的"逆境效应理论"。

关键词：逆境灯盏花灯盏乙素咖啡酸酯 Fv/Fm