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利益相关者视角下研学旅行行业发展的内在张力

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旅游科学 2020年第4期34卷 56-69页

作者：刘俊周彤昕华南师范大学旅游管理学院广东广州510006 华南师范大学研学旅行与休闲教育研究中心广东广州510006

国内研学旅行行业正处于井喷式快速发展阶段,但相关利益群体对研学旅行这一新生事物的理解不同,诉求各异。文章采用参与式观察、半结构式访谈等质性研究方法,对专业研学机构资深从业人员、学生、教师、家长4类关键利益相关者进行调查。... 详细信息

国内研学旅行行业正处于井喷式快速发展阶段,但相关利益群体对研学旅行这一新生事物的理解不同,诉求各异。文章采用参与式观察、半结构式访谈等质性研究方法,对专业研学机构资深从业人员、学生、教师、家长4类关键利益相关者进行调查。研究发现,基于各利益相关者的多元诉求,研学机构在实践运作中面临着4种主要的张力:(1)在课程设计上,面临教育取向与娱乐取向的矛盾;(2)在活动组织上,面临大规模化取向与小规模个性化取向的冲突;(3)在人才支撑上,面临研学高素质专业人才需求与供给之间的严重缺口;(4)在价值属性上,面临研学实践教育公益性与研学机构商业性的矛盾。文章提出未来需要在行政力量、市场力量和社会力量的多方参与下,逐步构建可持续高质量发展的研学旅行行业生态系统。

关键词：研学旅行利益相关者张力可持续发展质性研究

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森林地表死可燃物含水率预测模型研究进展

林业科学 2021年第4期57卷 142-152页

作者：孙龙刘祺胡同欣东北林业大学林学院哈尔滨150040

林火是影响森林生态系统的重要因子之一,林火蔓延和发展深受森林可燃物含水率的影响,尤其是林火的发生直接受地表死可燃物含水率的影响。因此,准确预测森林地表死可燃物含水率是预报森林火险和火行为的关键,加强森林死可燃物含水率预测... 详细信息

林火是影响森林生态系统的重要因子之一,林火蔓延和发展深受森林可燃物含水率的影响,尤其是林火的发生直接受地表死可燃物含水率的影响。因此,准确预测森林地表死可燃物含水率是预报森林火险和火行为的关键,加强森林死可燃物含水率预测模型研究尤为重要。从森林可燃物含水率的研究方法、研究模型及模型精度3方面综述研究现状,并对比评价现有模型。针对目前研究的诸多问题,提出5点展望:1)加强研究重点火险区野外含水率动态。利用已有的森林火险因子采集站和森林火险监测站获取不同环境因子和可燃物含水率及气象因子监测数据,构建重点火险区基于气象参数的森林可燃物含水率预测模型。2)加强森林可燃物的基础数据监测和收集。这可为全面构建森林火险等级系统奠定坚实的数据基础,同时还应建立精准的森林可燃物类型划分体系。3)加强研究可燃物含水率的空间异质性。应考虑不同影响因子下可燃物含水率动态,特别是了解小尺度内森林可燃物含水率的空间异质性,才能更准确进行林火预测预报。4)结合应用增强回归树(BRT)方法来提高模型精度。在可燃物含水率模型精度影响因子的研究中,运用BRT方法多次随机抽取一定量的数据,量化分析不同因子对模型精度的影响程度。5)结合GIS进行大尺度火险预警研究。综合应用RS和GIS技术,建立可燃物含水率的遥感反演模型,在准确模拟森林可燃物含水率空间分布的基础上,建立基于可燃物含水率的不同火险等级的预测模型。

关键词：森林可燃物地表死可燃物含水率预测模型模型精度火险预测预报

200 km·h^(-1)山区客货共线电气化铁路弓网受流的设计应用分析

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中国铁道科学 2007年第1期28卷 93-98页

作者：刘莉蓉潘英韩通新刘会平铁道第二勘察设计院电气化设计处四川成都610031 铁道科学研究院机车车辆研究所北京100081

受流质量是高速电气化铁路接触网需要解决的关键问题。以客货共线电气化铁路遂渝线为例,对影响接触网受流质量的波动传播速度、接触力、接触导线的动态高差及动态抬升量、接触网悬挂的弹性等进行分析,阐述提高受流质量的遂渝线接触网设... 详细信息

受流质量是高速电气化铁路接触网需要解决的关键问题。以客货共线电气化铁路遂渝线为例,对影响接触网受流质量的波动传播速度、接触力、接触导线的动态高差及动态抬升量、接触网悬挂的弹性等进行分析,阐述提高受流质量的遂渝线接触网设计原则和采用的设计参数,包括接触导线张力、不同区段的接触网悬挂方式及其新型接触网零部件、合理的跨距和结构高度等。综合试验表明:弓网接触力数值分布在现行规定的40~200 N之间,接触线一跨内的动态高差最大值为95 mm,硬点和冲击的数值分布在20g^50g范围内,遂渝线接触网的弓网受流性能满足列车速度220 km.h-1以下的安全运行要求。

关键词： 200 km·h^-1 客货共线电气化铁路弓网受流应用分析

以幻想言说历史:科尔森·怀特黑德《地下铁道》中的非洲未来主义书写

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山东外语教学 2023年第1期44卷 85-94页

作者：程彤歆刘白湖南师范大学外国语学院湖南长沙410081

当代美国非裔作家科尔森·怀特黑德的《地下铁道》运用科幻小说幻想元素书写了19世纪美国南方黑奴通过虚构的地下铁道逃至北方的故事。通过将黑奴隐喻为遭社会异化的外星人、将地下铁道视作黑人与现代科技相联结的桥梁,怀特黑德为美国... 详细信息

当代美国非裔作家科尔森·怀特黑德的《地下铁道》运用科幻小说幻想元素书写了19世纪美国南方黑奴通过虚构的地下铁道逃至北方的故事。通过将黑奴隐喻为遭社会异化的外星人、将地下铁道视作黑人与现代科技相联结的桥梁,怀特黑德为美国非裔如何逆转白人预设的种族悲观未来提供了可行方案。小说的非洲未来主义书写呈现出怀特黑德个人鲜明的理想主义色彩,其审美价值和当代意义值得关注。

关键词：科尔森·怀特黑德《地下铁道》非洲未来主义

Development and Validation of a Prognostic Risk Score System for COVID-19 Inpatients:A Multi-Center Retrospective Study in China

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Engineering 2022年第1期8卷 116-121页

作者： Ye Yuan Chuan Sun Xiuchuan Tang Cheng Cheng Laurent Mombaerts Maolin Wang Tao Hu Chenyu Sun Yuqi Guo Xiuting Li Hui Xu tongxin Ren Yang Xiao Yaru Xiao Hongling Zhu Honghan Wu Kezhi Li Chuming Chen Yingxia liu Zhichao Liang Zhiguo Cao Hai-Tao Zhang Ioannis Ch.Paschaldis Quanying liu Jorge Goncalves Qiang Zhong Li Yan School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Luxembourg Centre for Systems Biomedicine University of LuxembourgBelval L-4367Luxembourg Department of Plant Sciences University of CambridgeCambridge CB21TNUK Department of Emergency Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China AMITA Health Saint Joseph Hospital Chicago ChicagoIL 60657USA Department of Anesthesiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Huazhong University of Science and Technology-Wuxi Research Institute Wuxi 214174China Division of Cardiology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Institute of Health Informatics University College LondonLondon NW12DAUK Department of Biomedical Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Infectious Diseases Shenzhen Key Laboratory of Pathogenic Microbiology and ImmunologyNational Clinical Research Center for Infectious DiseaseThe Third People’s Hospital of Shenzhen(Second Hospital Affiliated with the Southern University of Science and Technology)Shenzhen 518055China Department of Electrical and Computer Engineering&Division of Systems Engineering&Department of Biomedical Engineering Boston UniversityBostonMA 02215USA

Coronavirus disease 2019(COVID-19)has become a worldwide *** patients of COVID-19 suffer from a high mortality rate,motivating the development of convenient and practical methods that allow clinicians to promptly identify high-risk ***,we have developed a risk score using clinical data from 1479 inpatients admitted to Tongji Hospital,Wuhan,China(development cohort)and externally validated with data from two other centers:141 inpatients from Jinyintan Hospital,Wuhan,China(validation cohort 1)and 432 inpatients from The Third People’s Hospital of Shenzhen,Shenzhen,China(validation cohort 2).The risk score is based on three biomarkers that are readily available in routine blood samples and can easily be translated into a probability of *** risk score can predict the mortality of individual patients more than 12 d in advance with more than 90%accuracy across all ***,the Kaplan-Meier score shows that patients can be clearly differentiated upon admission as low,intermediate,or high risk,with an area under the curve(AUC)score of *** summary,a simple risk score has been validated to predict death in patients infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2);it has also been validated in independent cohorts.

关键词： COVID-19 Risk score Mortality risk prediction

Role allocation tactics of soccer robots on RoboCup3D Simulation Platform

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Role allocation tactics of soccer robots on RoboCup3D Simula...

Formation Optimization Of RoboCup3D Soccer Robots Using Delaunay Triangulation Network

第30届中国控制与决策会议

作者： tongxin Cui Zhiwei Liang Keji He Zhiying Ke Qian Zhao Fang Fang Yuyan liu Nanjing University of Posts and Telecommunications Key Laboratory of Measurement and Control of CSE （School of Automation Southeast University）

A Markov Decision Process（MDP） is employed to optimize the role allocation of soccer robots on RoboCup3D simulation platform in this paper. Role allocation tactics of soccer robots are modeled based on Markov Decision Process（MDPs） considering various factors of five different types of robot in simulation environment including distance, orientation, falling, speed and other factors. Then a linear function approximation based on learning algorithm is applied to solve the action value function of the MDP model. The role of search for the optimal allocation scheme improves the efficiency of the entire team’s offensive defense. The experimental results establish the effectiveness of our methods.

关键词： RoboCup3D soccer robots Markov Decision Process role allocation

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Formation Optimization Of RoboCup3D Soccer Robots Using Dela...

基于综合评价识别法的智能变电站虚回路在线状态监测技术研究

第30届中国控制与决策会议

作者： Keji He Zhiwei Liang tongxin Cui Zhiying Ke Zichang liu Qian Zhao Fang Fang College of Automation Nanjing University of Posts and Telecommunications

In RoboCup3D robot simulation platform,team collaboration plays an important role in order to win a *** paper proposes a novel method of team formation ***,the Delaunay triangulation method is applied to divide the football field into small triangular ***,the SBSP mechanism for the team is employed to choose a reasonable ***,the Linear interpolation method is used to calculate robots’ positions in different formations with data set given *** a result,the team can get the most optimal formation for the football in different *** experimental results demonstrate the effectiveness of our methods.

关键词： RoboCup Soccer robots Delaunay triangulation SBSP mechanism Formation design Linear interpolation method

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电力系统保护与控制 2019年第3期47卷 182-187页

作者：高旭刘宏君杜丽艳武同心国网冀北电力有限公司北京100081 长园深瑞继保自动化有限公司广东深圳518057

为了建设全过程模块化的智能变电站,实时地监测继电保护装置,提出了一种智能变电站虚回路的在线状态监测技术。在智能变电站全过程模块化管控策略的基础上,研究了SCD文件的图形化展示技术,提供了装置自身运行状态、软压板投运状态、逻... 详细信息

为了建设全过程模块化的智能变电站,实时地监测继电保护装置,提出了一种智能变电站虚回路的在线状态监测技术。在智能变电站全过程模块化管控策略的基础上,研究了SCD文件的图形化展示技术,提供了装置自身运行状态、软压板投运状态、逻辑链路状态等综合信息。同时在线状态监测系统中将熵权法和灰色关联分析法相结合,用于综合评价识别智能变电站虚回路中的故障类型,及时消除故障隐患,提高现场运维人员的工作效率,进而推进变电站智能化的发展。

关键词：智能变电站 SCD文件可视化熵权法灰色关联分析在线状态检测

High-quality genome assemblies for two Australimusa bananas(Musa spp.)and insights into regulatory mechanisms of superior fiber properties

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Plant Communications 2024年第1期5卷 245-261页

作者： Run Zhou Shuo Wang Ni Zhan Weidi He Guiming Deng tongxin Dou Xi-Tong Zhu Wen-Zhao Xie Yu-Yu Zheng Chunhua Hu Fangcheng Bi Huijun Gao Tao Dong Siwen liu Chunyu Li Qiaosong Yang Lingqiang Wang Jia-Ming Song Jiangbo Dang Qigao Guo Ganjun Yi Ling-Ling Chen Ou Sheng Institute of Fruit Tree Research Guangdong Academy of Agricultural SciencesKey Laboratory of South Subtropical Fruit Biology and Genetic Resource UtilizationMinistry of Agriculture and Rural AffairsGuangdong Provincial Key Laboratory of Tropical and Subtropical Fruit Tree ResearchGuangzhou 510640China College of Informatics Huazhong Agricultural UniversityWuhan 430070China State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources College of Life Science and TechnologyGuangxi UniversityNanning 530004China College of Horticulture and Landscape Architecture Southwest UniversityChongqing 400715China

Bananas(Musa spp.)are monocotyledonous plants with high genetic diversity in the Musaceae family that are cultivated mainly in tropical and subtropical *** fruits are a popular food,and the plants themselves have diverse *** genetic groups(genomes)are thought to have contributed to current banana cultivars:Musa acuminata(A genome),Musa balbisiana(B genome),Musa schizocarpa(S genome),and species of the Australimusa section(T genome).However,the T genome has not been effectively ***,we present the high-quality TT genomes of two representative accessions,Abaca(Musa textilis),with high-quality naturalfiber,and Utafun(Musa troglodytarum,Fe’i group),with abundant *** the Abaca and Utafun assemblies comprise 10 pseudochromosomes,and their total genome sizes are 613 Mb and 619 Mb,*** genome analysis revealed that the larger size of the T genome is likely attributable to rapid expansion and slow removal of *** with those of Musa AA or BB accessions or sisal(Agava sisalana),Abacafibers exhibit superior mechanical properties,mainly because of their thicker cell walls with a higher content of cellulose,lignin,and *** of MusaCesA cellulose synthesis genes peaks earlier in Abaca than in AA or BB accessions during plant development,potentially leading to earlier cellulose accumulation during secondary cell wall *** Abaca-specific expressed gene MusaMYB26,which is directly regulated by MusaMYB61,may be an important regulator that promotes precocious expression of secondary cell wall ***,MusaWRKY2 and MusaNAC68,which appear to be involved in regulating expression of MusaLAC and MusaCAD,may at least partially explain the high accumulation of lignin in *** work contributes to a better understanding of banana domestica-tion and the diverse genetic resources in the Musaceae family,thus providing resources for Musa genetic improvement.

关键词： Australimusa bananas T genome Musaceae evolution structural variations fiber