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Spatial and temporal dynamics of microbial community composition and factors influencing the surface water and sediments of urban rivers

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Journal of Environmental Sciences 2023年第2期124卷 187-197页

作者： Hongjie Wang xingchun liu Yali Wang Shengqi Zhang Guangming Zhang Yangyang Han Mengxiang Li Ling liu College of Ecology and Environment Hebei UniversityBaoding 071002China Institute of Life Science and Green Development Hebei UniversityBaoding 071002China Hebei Key Laboratory of Close-to-Nature Restoration Technology of Wetlands Baoding 071002China School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300130China

The temporal and spatial characteristics of urban river bacterial communities help us understand the feedback mechanism of bacteria to changes in the aquatic *** Fuhe River plays an important role in determining the water ecological environment of Baiyangdian Lake.16S rRNA gene sequencing was used to study the microbial distribution characteristics in the Fuhe River in different *** results showed that some environmental factors of the surface water(ammonia nitrogen(NH_(3)^(-)N),total nitrogen(TN),and total phosphorus(TP))were different on the spatial and temporal ***,there were no seasonal differences in the contents of TN,TP,total organic carbon(TOC),or heavy metals in the *** distributions of Cyanobacteria,Actinomycetes and Firmicutes in the water and Actinomycetes and Planctomycetes in the sediments differed significantly among seasons(P<0.05).There were significant spatial differences in bacteria in the surface water,with the highest abundance of Proteobacteria recorded in the river along with the highest nutrient concentration,while the abundance of Bacteroidetes was higher in the upstream than the *** communities in the water weremost sensitive to temperature(T)and the TP concentration(P<0.01).Moreover,differences in the bacterial community were better explained by the content of heavy metals in the sediments than by the chemical characteristics.A PICRUStmetabolic inference analysis showed that the effect of high summer temperatures on the enzyme action led to an increase in the abundances of the metabolic-related genes of the river microorganisms.

关键词： Fuhe river Surface water Sediment Bacterial community Spatial and temporal distribution Functional prediction

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Algorithm for Calculating Torque Base in Vehicle Traction Control System

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1130-1137页

作者： LI Hongzhi LI Liang SONG Jian WU Kaihui QIAO Yanjuan liu xingchun XIA Yongguang State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China Chang'an Automotive Engineering General Research Institute Chongqing 400023 China

Existing research on the traction control system（TCS） mainly focuses on control methods, such as the PID control, fuzzy logic control, etc, aiming at achieving an ideal slip rate of the drive wheel over long control periods. The initial output of the TCS （referred to as the torque base in this paper）, which has a great impact on the driving performance of the vehicle in early cycles, remains to be investigated. In order to improve the control performance of the TCS in the first several cycles, an algorithm is proposed to determine the torque base. First, torque bases are calculated by two different methods, one based on states judgment and the other based on the vehicle dynamics. The confidence level of the torque base calculated based on the vehicle dynamics is also obtained. The final torque base is then determined based on the two torque bases and the confidence level. Hardware-in-the-loop（HIL） simulation and vehicle tests emulating sudden start on low friction roads have been conducted to verify the proposed algorithm. The control performance of a PID-controlled TCS with and without the proposed torque base algorithm is compared, showing that the proposed algorithm improves the performance of the TCS over the first several cycles and enhances about 5% vehicle speed by contrast. The proposed research provides a more proper initial value for TCS control, and improves the performance of the first several control cycles of the TCS.

关键词： traction control system torque base torque control initial value

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Effectiveness of Interventions to Control Transmission of Reemergent Cases of COVID-19--Jilin Province,China,2020

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China CDC weekly 2020年第34期2卷 651-654页

作者： Qinglong Zhao Meng Yang Yao Wang Laishun Yao Jianguo Qiao Zhiyong Cheng Hanyin liu xingchun liu Yuanzhao Zhu Zeyu Zhao Jia Rui Tianmu Chen Jilin Provincial Center for Disease Control and Prevention ChangchunJilinChina State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics School of Public HealthXiamen UniversityXiamenFujianChina Jilin Municipal Center for Disease Control and Prevention Jilin CityJilin ProvinceChina Shulan Center for Disease Control and Prevention ShulanJilin CityJilin ProvinceChina

What is already known about this topic?COVID-19 has a high transmissibility calculated by mathematical *** dynamics of the disease and the effectiveness of intervention to control the transmission remain unclear in Jilin Province,*** is added by this report?This is the first study to report the dynamic characteristics and to quantify the effectiveness of interventions implemented in the second outbreak of COVID-19 in Jilin Province,*** effective reproduction number of the disease before and after May 10 was 4.00 and p<0.01,*** combined interventions reduced the transmissibility of COVID-19 by 99% and the number of cases by 98.36%.What are the implications for public health practice?The findings of this study would add data on the transmission of COVID-19 and provide evidence to prepare the second outbreak transmission of the disease in other areas of China even in many other countries.

关键词： Province,China Jilin COV

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Control measures during the COVID-19 outbreak reduced the transmission of hand,foot,and mouth disease

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Journal of Safety Science and Resilience 2021年第2期2卷 63-68页

作者： Yan Niu Li Luo Jia Rui Shiting Yang Bin Deng Zeyu Zhao Shengnan Lin Jingwen Xu Yuanzhao Zhu Yao Wang Meng Yang xingchun liu Tianlong Yang Weikang liu Peihua Li Zhuoyang Li Chan liu Jiefeng Huang Tianmu Chen Chinese Center for Disease Control and Prevention Beijing102206China State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics School of Public HealthXiamen UniversityXiamenFujian361102China

Control measures during the coronavirus disease 2019(COVID-19)outbreak may have limited the spread of infectious *** study aimed to analyze the impact of COVID-19 on the spread of hand,foot,and mouth disease(HFMD)in China.A mathematical model was established to fit the reported data of HFMD in six selected cities in China's Mainland from 2015 to *** absolute difference(AD)and relative difference(RD)between the reported incidence in 2020,and simulated maximum,minimum,or median incidence of HFMD in 2015-2019 were *** incidence and R effof HFMD have decreased in six selected cities since the outbreak of COVID-19,and in the second half of 2020,the incidence and R effof HFMD have *** results show that the total attack rate(TAR)in 2020 was lower than the maximum,minimum,and median TAR fitted in previous years in six selected cities(except Changsha City).For the maximum,median,minimum fitted TAR,the range of RD(%)is 42·20-99·20%,36·35-98·41%48·35-96·23%(except Changsha City)*** preventive and control measures of COVID-19 have significantly contributed to the containment of HFMD transmission.

关键词： HFMD Transmissibility COVID-19 Effective reproduction number Mathematical model

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普通中小学教师参与决策的因素分析

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上海教育科研 2007年第10期 31-34页

作者：刘兴春北京师范大学教育管理学院 100875

现代学校制度的核心是"处理学校与政府、学校与家庭、社区的关系以及学校内部关系"。建立和谐的校内关系的必由之路是学校管理的民主化。因此,完善学校内部治理机制,提高教师学校决策的参与度,也是现代学校制度建设的重要课题。本研究... 详细信息

现代学校制度的核心是"处理学校与政府、学校与家庭、社区的关系以及学校内部关系"。建立和谐的校内关系的必由之路是学校管理的民主化。因此,完善学校内部治理机制,提高教师学校决策的参与度,也是现代学校制度建设的重要课题。本研究通过问卷调查对普通中小学教师参与决策的意愿和实际状况进行了比较研究,文章主要探讨教师期望参与决策的内容,以及教师的性别、教龄、学历、学校类别等因素对教师参与的影响,根据分析提出了相应的建议。

关键词：教师参与普通中小学学校决策现代学校制度建设内部治理机制学校管理问卷调查教师期望

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SCI/RT总线的扩展子优先级流量均衡

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北京航空航天大学学报 2010年第1期36卷 91-94页

作者：崔剑刘兴春李铮北京航空航天大学电子信息工程学院北京100191

建立了基于OPNET软件的SCI/RT(Scalable Coherent Interface for RealTime)TRAIN协议仿真模型,对流量均衡问题进行仿真分析.结果显示,当环路负载增加时,每个节点流量的增量是不同的.在环路处于重负载时,远离管理者的节点得到的流量近似... 详细信息

建立了基于OPNET软件的SCI/RT(Scalable Coherent Interface for RealTime)TRAIN协议仿真模型,对流量均衡问题进行仿真分析.结果显示,当环路负载增加时,每个节点流量的增量是不同的.在环路处于重负载时,远离管理者的节点得到的流量近似于零,而靠近管理者的节点基本上占用了所有的环路流量.SCI/RT TRAIN协议提出管理者迁移流量均衡方式解决这个问题.通过对8节点环路进行仿真,得出管理者迁移方法的均衡效果依赖于管理者在环路的配置方式的结论,当每个节点均具有管理者功能时,环路均衡效果达到最好.提出了扩展子优先级的流量均衡新方法.8节点环路的仿真结果显示,该方法具有更好的流量均衡能力和更高的节点流量.同时,通过对扩展子优先级均衡方法在6节点,10节点和12节点环路的仿真,证明了该方法在不同规模的环路中均可使用.

关键词：数据通信系统互联网络接口流量实时系统

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基于最短路径的SCI网络拓扑结构研究

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航空学报 2007年第5期28卷 1130-1136页

作者：刘兴春邵搏李铮北京航空航天大学电子信息工程学院北京100083

从航空电子系统的需求出发,对可扩展一致性接口(SCI)网络的拓扑结构进行了最短路径(跳数)研究。利用图论中的邻接矩阵变换方法,根据航空电子系统中SCI节点端口数的限制及SCI网络的小环组合结构的特点,对SCI推荐的网格形和蝶形两种网络... 详细信息

从航空电子系统的需求出发,对可扩展一致性接口(SCI)网络的拓扑结构进行了最短路径(跳数)研究。利用图论中的邻接矩阵变换方法,根据航空电子系统中SCI节点端口数的限制及SCI网络的小环组合结构的特点,对SCI推荐的网格形和蝶形两种网络进行了平均最小跳数的计算和分析,得出了SCI网络中小环方向的改变对平均最小跳数有影响的结论,并得到了该两种网络结构中平均最小跳数最少的拓扑形式。

关键词：通信与信息系统航空电子系统最短路径 SCI网络拓扑结构

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SCI网络拓扑结构的可生存性

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北京航空航天大学学报 2007年第9期33卷 1072-1076页

作者：刘兴春邵搏李铮北京航空航天大学电子信息工程学院北京100083

从航空电子系统的需求出发,研究了适于航电系统的SCI(Scalable Coherent Interface)网络拓扑结构的可生存性.选择了由双节点或skip-a-node结构形式构成的网格形、蝶形等适于SCI网络的拓扑形式并构造了二种网络拓扑结构以便于不同结构的... 详细信息

从航空电子系统的需求出发,研究了适于航电系统的SCI(Scalable Coherent Interface)网络拓扑结构的可生存性.选择了由双节点或skip-a-node结构形式构成的网格形、蝶形等适于SCI网络的拓扑形式并构造了二种网络拓扑结构以便于不同结构的可生存性比较.同时考虑边及节点损坏的情况,利用图的邻接矩阵对网络连通关系进行了计算和分析,找到并印证了具有高可生存性的拓扑形式,同时发现相同结构下小环方向的改变对可生存性也有影响.

关键词：航空电子系统拓扑结构 SCI环可生存性连通关系

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Feasibility of Booster Vaccination in High-Risk Populations for Controlling Coronavirus Variants—China,2021

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China CDC weekly 2021年第50期3卷 1071-1074,I0001-I0004页

作者： Kangguo Li Zeyu Zhao Hongjie Wei Jia Rui Jiefeng Huang Xiaohao Guo Yichao Guo Shiting Yang Guzainuer Abudurusuli Li Luo xingchun liu Yao Wang Jingwen Xu Yuanzhao Zhu Meng Yang TianlongYang Weikang liu Bin Deng Chan liu Zhuoyang Li Peihua Li Shanshan Yu Zimei Yang Yanhua Su Benhua Zhao Yan Niu Tianmu Chen State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics School of Public HealthXiamen UniversityXiamenFujianChina Universitéde Montpellier MontpellierFranceCIRADIntertrypMontpellierFranceIESUniversitéde Montpellier-CNRSMontpellierFrance Chinese Center for Disease Control and Prevention BeijingChina.

Introduction:Vaccination booster shots are completely necessary for controlling breakthrough infections of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)in *** study aims to estimate effectiveness of booster vaccines for high-risk populations(HRPs).Methods:A vaccinated Susceptible-Exposed-Symptomatic-Asymptomatic-Recovered/Removed(SEIAR)model was developed to simulate scenarios of effective reproduction number(Reff)from 4 to *** number of infectious and asymptomatic cases were used to evaluated vaccination ***:Our model showed that we could not prevent outbreaks when covering 80%of HRPs with booster unless Reff=4.0 or the booster vaccine had efficacy against infectivity and susceptibility of more than 90%.The results were consistent when the outcome index was confirmed cases or asymptomatic ***:An ideal coronavirus disease 2019(COVID-19)booster vaccination strategy for HRPs would be expected to reach the initial goal to control the transmission of the Delta variant in ***,the recommendation for the COVID-19 booster vaccine should be implemented in HRPs who are already vaccinated and could prevent transmission to other groups.

关键词： vaccine acute respiratory

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问题表征方式与数学问题解决的研究

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心理科学进展 2002年第3期10卷 264-269页

作者：胥兴春刘电芝西南师范大学教育科学学院西南师范大学教育科学学院重庆400715

阐述了问题表征在数学问题解决中的作用;重点探讨了抽象表征、原理表征、图式表征等不同表征方式与数学问题解决的关系;最后提出通过选择与转换两种策略来寻求适宜的问题表征方式。

关键词：问题表征数学问题解决表征方式选择转换

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