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Journal of Computational Mathematics 2007年第5期25卷 531-542页

作者： Zhongxiao jia yuquan Sun Department of Mathematical Sciences Tsinghua University Beijing 100084 China

Based on the generalized minimal residual （GMRES） principle, Hu and Reichel proposed a minimal residual algorithm for the Sylvester equation. The algorithm requires the solution of a structured least squares problem. They form the normal equations of the least squares problem and then solve it by a direct solver, so it is susceptible to instability. In this paper, by exploiting the special structure of the least squares problem and working on the problem directly, a numerically stable QR decomposition based algorithm is presented for the problem. The new algorithm is more stable than the normal equations algorithm of Hu and Reichel. Numerical experiments are reported to confirm the superior stability of the new algorithm.

关键词： Least-squares solution Preconditioning Generalized singular value decomposition.

The simulation and analysis of pedestrian crowd and behavior

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Science China(Technological Sciences) 2009年第6期52卷 1762-1767页

作者： HU QingMei FANG WeiNing jia yuquan DENG Ye State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

Pedestrian crowd in public buildings is usually a hidden *** more serious the crowd,the higher the accident risk,and the heavier the casualties and loss may *** on the social force model,this paper puts forward an improved model which takes into account the anisotropic charac-teristic of pedestrian movement and the avoidance of dynamic congested ***,the al-gorithm has been optimized with the help of static force grid,so the simulation becomes more veritable and computational speed is also greatly *** improved model is also applied to research on the characters of pedestrian crowd,and the conclusion can provide a basis for the risk assessment of pedestrian crowd and the design of public buildings.

关键词： social force model anisotropic behavior the locality principle pedestrian crowd

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矿井通风系统分级控制研究

工矿自动化 2018年第12期44卷 30-33页

作者：魏引尚贾玉泉王奕博董丁稳西安科技大学安全科学与工程学院陕西西安710054 西安科技大学教育部西部矿井开采及灾害防治重点实验室陕西西安710054

针对现有矿井通风系统控制未从通风系统整体角度考虑的问题,基于矿井通风系统结构及风量分布特征,提出了一种矿井通风系统分级控制方法。首先,通过比较通风状况参数的实时采集值和安全设定值,得出各用风地点通风状况参数偏差量;然后,利... 详细信息

针对现有矿井通风系统控制未从通风系统整体角度考虑的问题,基于矿井通风系统结构及风量分布特征,提出了一种矿井通风系统分级控制方法。首先,通过比较通风状况参数的实时采集值和安全设定值,得出各用风地点通风状况参数偏差量;然后,利用自动纠偏控制器对偏差量进行在线整定和修改,并通过PID控制器获得通风状态调整参数;最后,智能控制模块根据通风状态调整参数,分别控制主要通风机供电模块的变频器、电动风门、压风管路末端的充气式气囊,实现全矿风量控制、采区风量控制、工作面风量控制3个层次的风量动态调节。该控制方法满足通风系统内风量循序、系统、连贯地调控要求。

关键词：矿井通风系统风量分级控制全矿风量控制采区风量控制工作面风量控制

Operational Plan,Effect Verification,and Key Technical Settings for a Stadium-Scale Artificial Rain Reduction Experiment

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Journal of Meteorological Research 2023年第5期37卷 643-665页

作者： yuquan ZHOU Siyao LIU Miao CAI Junlin LONG jia WANG CMA Cloud–Precipitation Physics and Weather Modification Key Laboratory(CPML) Weather Modification CentreChina Meteorological Administration(CMA)Beijing 100081 School of Electronic Engineering Chengdu University of Information TechnologyChengdu 610225 College of Meteorological Observation Chengdu University of Information Technology/CMA Key Laboratory of Atmospheric SoundingChengdu 610225 jiangsu Weather Modification Center Nanjing 210000

To explore the key technologies of artificial weather modification for specific targets(e.g.,a stadium)and improve the efficiency of artificial rainfall modification for major events,this study conducts an artificial rainfall reduction experiment for the closing ceremony of Nanjing Youth Olympic Games on 28 August *** retrievals,radar observations,sounding data,and other sources of information as well as Cloud and Precipitation Accurate Analysis System(CPAS)are used in this *** main conclusions are as follows.(1)On 28 August 2014,a large-scale cumulus cloud system with mixed-phase stratocumulus and stratus precipitation was *** system was influenced by the weak shear of a low-level trough and the precipitation was dominated by cold clouds with dry layers between ***,we adopted the crystal-priming over-catalytic hypothesis and conducted a rocket-catalytic rain abatement operation at a certain distance(100–25 km)from the *** shootings of different intensities were implemented for two echoes that affected the stadium successively(two rounds of 15 rocket shootings within15 min for an isolated weak echo IA;multiple rounds of 156 rocket shootings within 80 min for a strong echo IB).Amazingly,after the shootings with the catalysis in the air,reflectivity of the two echoes was reduced at all altitudes with the most significant reduction at the 2-km altitude,and the time needed for the obvious reduction was 40 *** most obvious reduction of the two echoes then maintained for 60 and 53 min,respectively,and the operation time needed for the echo zone to recover after the stop of rocket shooting was 108 min for echo IA and 90 min for echo *** two echoes moving across the stadium during the time period of the closing ceremony(2000–2130 local time)were at their minimal strengths,with almost no echo over the target *** demonstrates that the rocket shooting strategy of over-crystallization catalysis is effective,and th

关键词： target area artificial rainfall abatement radar monitoring weather modification plan effect analysis

Centromere repositioning and shifts in wheat evolution

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Plant Communications 2023年第4期4卷 117-131页

作者： Jing Zhao Yilin Xie Chuizheng Kong Zefu Lu Haiyan jia Zhengqiang Ma Yijing Zhang Dangqun Cui Zhengang Ru yuquan Wang Rudi Appels Jizeng jia Xueyong Zhang Key Laboratory of Crop Gene Resources and Germplasm Enhancement Ministry of Agriculture and Rural Affairs/Institute of Crop ScienceChinese Academy of Agricultural SciencesBeijing 100081China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China Nanjing Agricultural University Nanjing 210095JiangsuChina Agronomy College/National Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops Henan Agricultural UniversityZhengzhou 450046China Henan Institute of Science and Technology Xinxiang 453003China Agriculture Victoria Research Department of Economic DevelopmentJobsTransport and ResourcesAgriBioBundooraVIC 3083Australia University of the Chinese Academy of Sciences Beijing 100049China

The centromere is the region of a chromosome that directs its separation and plays an important role in cell division and reproduction of *** the dynamics of centromeres is an alternative strategy for exploring the evolution of ***,we comprehensively analyzed centromeres from the de novoassembled common wheat cultivar Aikang58(AK58),Chinese Spring(CS),and all sequenced diploid and tetraploid ancestors by chromatin immunoprecipitation sequencing,whole-genome bisulfite sequencing,RNA sequencing,assay for transposase-accessible chromatin using sequencing,and comparative *** found that centromere-associated sequences were concentrated during tetraploidization and *** repeats of wheat(CRWs)have undergone expansion during wheat evolution,with strong interweaving between the A and B subgenomes post *** found that CENH3 prefers to bind with younger CRWs,as directly supported by immunocolocalization on two chromosomes(1A and 2A)of wild emmer wheat with dicentromeric regions,only one of which bound with *** a comparison of AK58 with CS,obvious centromere repositioning was detected on chromosomes 1B,3D,and *** active centromeres showed a unique combination of lower CG but higher CHH and CHG methylation *** also found that centromeric chromatin was more open than pericentromeric chromatin,with higher levels of gene expression but lower gene *** introgression between tetraploid and hexaploid wheat also had a strong influence on centromere position on the same *** study also showed that active wheat centromeres were genetically and epigenetically determined.

关键词： wheat evolution centromere repositioning epigenetic modifications

Resilience effects for household food expenditure and dietary diversity in rural western China

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Journal of Integrative Agriculture 2024年第2期23卷 384-396页

作者： Xiao Han Kaiyu Lyu Fengying Nie yuquan Chen Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081China Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081China Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China

A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary *** study quantifies rural household resilience in western China,identifies the three pillars(absorptive capacity,adaptive capacity,and transformative capacity)contribution to resilience,and then establishes the estimated Resilience Capacity Index(RCI)linked with food security and dietary diversity supported by the multiple indicator multiple cause(MIMIC)*** show that,despite geographical heterogeneity,the RCI consistently increased from 2015 to *** with a higher RCI inheriting better capacity to deal with risk and shocks are significantly and positively correlated with increasing food expenditure and diversifying food *** can be because resilient households will allocate more money to food expenditure instead of saving for livelihood ***,policymakers can provide more incentives for rural households to adopt more dynamic and effective risk management ***,in turn,could yield positive spillover effects by preventing human capital loss associated with dietary-related chronic diseases and mortality.

关键词： resilience food expenditure dietary diversity China risk management

A New High Quality EAF Charge

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Journal of University of Science and Technology Beijing 2001年第1期8卷 20-21页

作者： jianliang Zhang, yuquan Liu, Zongwang Zhang, Jinlin jia ,Yongmei Zhang Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China Tianjin Iron Corporation, Handan 056000, China Metallurgy School Univ. of Science/Technology Beijing Beijing 100083 China

In order to solve the problem of the shortage of scrap, especially high quality scrap, granular pig iron, a new substitute for scrap or DRI (direct reduction iron) has been developed. The technical process of decarbonized granular pig iron has been evaluated. The result shows that this new process is superior to direct reduction process in product quality, construction investment, operation flexibility, production efficiency etc. Decarbonized granular pig iron (DGPI) not only can be used as conventional scrap but also can be charged into EAF as high purity burden equivalent to heavy scrap.

关键词： decarbonized granular pig iron scrap DRI

Influence of CdS films synthesized by different methods on the photovoltaic performance of CdTe/CdS thin film solar cells

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Chinese Physics B 2020年第9期29卷 615-621页

作者： Jun Wang yuquan Wang Cong Liu Meiling Sun Cao Wang Guangchao Yin Fuchao jia Yannan Mu Xiaolin Liu Haibin Yang School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China Department of Physics and Chemistry Heihe UniversityHeihe 164300China State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012China

The cadmium sulphide (CdS) film is grown on cadmium telluride (CdTe) nanorods (NRs) arrays by different methods such as chemical bath deposition (CBD), magnetron sputtering (MS), and homogenous precipitation (HP) techniques. The impact of various deposition methods is explored in detail on the growth of CdTe/CdS composite film, the CdTe/CdS interface property, and solar cell efficiency. Compared to the CBD and HP methods, the MS method can improve the growth of the CdS on CdTe NRs with high crystalline quality. The device based on the CdS film prepared by the MS method demonstrates excellent photovoltaic performance, which has the potential for applications in solar cells.

关键词： CdS chemical bath deposition magnetron sputtering homogenous precipitation

砷化镓PHEMT功率管高温加速寿命试验研究

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固体电子学研究与进展 2014年第4期34卷 371-376页

作者：贾东铭杨洋林罡金毓铨南京电子器件研究所南京210016

通过解决温度提升、温度稳定控制、寄生振荡抑制等关键问题,使砷化镓PHEMT功率器件的高温加速寿命试验得以实施。经过2 832h试验,三个分组的样品均出现了失效。对样品的失效模式与机理进行了分析,并确定了失效原因。对试验数据进行分析... 详细信息

通过解决温度提升、温度稳定控制、寄生振荡抑制等关键问题,使砷化镓PHEMT功率器件的高温加速寿命试验得以实施。经过2 832h试验,三个分组的样品均出现了失效。对样品的失效模式与机理进行了分析,并确定了失效原因。对试验数据进行分析得到了该器件的寿命分布与寿命加速特性,并对分析结论进行了验证。

关键词：砷化镓微波功率管平均失效前时间

Pathogenic conversion of regulatory B10 cells into osteoclastpriming cells in rheumatoid arthritis

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Pathogenic conversion of regulatory B10 cells into osteoclas...