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Distribution characteristics of zooplankton in the south part of Taiwan Strait in summer

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Acta Oceanologica Sinica 2000年第1期19卷 127-135页

作者： Zhu Changshou Huang Jiaqi lin junzhou Du Qinghong Chen Xu Li Shaojing (1. Fujian Institute of Oceanology, Xiamen 361012, China 2. Department of Oceanography, Xiamen University, Xiamen 361005, China) Fujian Institute of Oceanology Xiamen 361012 China Department of Oceanography Xiamen University Xiamen 361005 China

Based on the samples collected mesoplankton net from the south part Of Taiwan Strait (22. 25 --24. 65N, 117. 50 -- 120. 00E) in August 1997, 292 species of zooplankton and 11 groups of meroplankton were identified. In the survey waters, Copepoda was dominant in either species or individual numbers. The diversity (H' ) was 5. 11 and the ratio of diversity to evenness (J ) was 7. 10, showing that the diversity of zooplankton was exceedingly high in the survey waters. Three zooplankton communities were clearly divided by systematical cluster analysis, indicating that the biotopes of these zooplankton communities may serve as the evidence for the basic status of distribution of water masses during the investigation.

关键词： Zooplankton species diversity distribution characteristics Taiwan Strait

基于有源智能反射面反射单元分组的反射调制系统

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电子与信息学报 2024年第7期46卷 2765-2772页

作者：熊军洲李国权王钥涛林金朝重庆邮电大学通信与信息工程学院重庆400065 重庆电子科技职业大学电子与物联网学院重庆401331

为克服智能反射面(IRS)辅助通信系统的“双重路径损耗”,进一步提升系统的可靠性和频谱效率,该文提出一种基于有源IRS反射单元分组的反射调制(RM)系统方案,利用有源反射单元分组的数量来传输额外信息。然后基于矩母函数推导了最大似然... 详细信息

为克服智能反射面(IRS)辅助通信系统的“双重路径损耗”,进一步提升系统的可靠性和频谱效率,该文提出一种基于有源IRS反射单元分组的反射调制(RM)系统方案,利用有源反射单元分组的数量来传输额外信息。然后基于矩母函数推导了最大似然检测算法下基站发射符号与有源反射单元分组数量的平均成对错误概率,获取到系统的理论比特错误概率(BEP)上界以及可达速率。仿真结果验证了理论推导的准确性,同时表明所提方案具有更优的误码性能和频谱效率。

关键词：智能反射面反射调制比特错误概率可达速率

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超薄沥青路面早期损害裂缝和车辙的特点分析

武汉理工大学学报（交通科学与工程版） 2014年第1期38卷 176-180页

作者：苏婷婷呙润华林俊舟李红学乔小兵刘剑赵恒清华大学土木系北京100084 中国建筑股份有限公司北京100000

根据非洲刚果(布)国家一号公路实地实验数据,采用MEPDG软件进行建模,在实际荷载水平及路面材料性质下,分析超薄沥青路面早期病害的原因,变化各层材料弹性模量和厚度,对车辙深度和疲劳裂缝等指标对结构强度和早期损害的影响,取95%保证率... 详细信息

根据非洲刚果(布)国家一号公路实地实验数据,采用MEPDG软件进行建模,在实际荷载水平及路面材料性质下,分析超薄沥青路面早期病害的原因,变化各层材料弹性模量和厚度,对车辙深度和疲劳裂缝等指标对结构强度和早期损害的影响,取95%保证率下符合可靠性要求的结果.进一步分析路面结构对高交通增长率的抵抗能力强弱,提出针对降低超薄沥青路面早期损害的措施.

关键词：道路工程超薄沥青路面结构早期损害裂缝车辙

Pressureless crystallization of glass toward scintillating composite with high crystallinity for radiation detection

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Journal of Materials Science & Technology 2022年第34期129卷 173-180页

作者： junzhou Tang Shichao Lv Ziyu lin Guanxin Du Manyun Tang Xu Feng Junpeng Guo Xiang Li Junfeng Chen Lei Wei Jianrong Qiu Shifeng Zhou State Key Laboratory of Luminescent Materials and Devices School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640China Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques Guangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and DevicesGuangzhou 510640China Shanghai Hapstar M&E Equipment Co. Ltd.Shanghai 201109China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 201800China School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore College of Optical Science and Engineering State Key Laboratory of Modern Optical InstrumentationZhejiang UniversityHangzhou 310027China

The construction of scintillating ceramics is of great technological importance for various fundamental applications, including medical diagnostic, security inspection, resource exploration and particle physics. The chief challenge is the facile and scalable synthesis of scintillating ceramics with the desirable combination of pore-free, reliable mechanical properties and excellent scintillating performance. Here we present a pressureless glass crystallization strategy for the construction of scintillating composite with high crystallinity. The fabricated scintillating composites are featured by small optical turbidity, excellent mechanical properties, and efficient scintillating luminescence with the scintillating light yield of 15,000 pH/MeV and about 2.46 times higher than that of the commercial BGO single crystal. Moreover, the scintillating composite derived radiation detector device is successfully elaborated. The practical application for monitoring gamma ray is demonstrated and the precision of the device is less than that of the tolerable deviation of 30%. Our results suggest an innovative approach for expanding the category of scintillating material candidates, pointing to practical application in the field of radiation detection.

关键词： Glass Glass crystallization Optical materials Composite Luminescence

Evaluation Method for Tunneling Stability of TBM Cutterhead

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World Journal of Engineering and Technology 2019年第2期7卷 1-9页

作者： Zhaohui Xu Ye Er-ken∙Zha Mu-ti lin Xue Fengtao Wang Jing Chen junzhou Huo School of Mechanical Engineering Dalian University of TechnologyDalianChina Ergis River Basin Development Project Construction Management Bureau UrumchiChina School of Navigation and Shipbuilding Engineering Dalian Ocean UniversityDalianChina

In the process of tunneling of tunnel boring machine (TBM), different geological conditions often correspond to different working conditions, and the randomness of geological conditions also causes the order of occurrence of each working condition to be different. Under the conversion of different working conditions, this makes the vibration of different types of cutterheads different. How to choose the appropriate type of cutterhead according to different geological conditions is very important for saving engineering cost and increasing cutterhead life. In view of the above situation, this paper proposes a stability evaluation method during the TBM tunneling process to select the appropriate cutterhead type. Firstly, the corresponding relationship between geology and working conditions is established according to different geological conditions, and the input loads corresponding to geological conditions are obtained. Then, it is substituted into the dynamic model of the cutterhead system, the vibration response boundaries of each degree of freedom are obtained by solving. And the average value of the maximum boundary amplitude of each degree of freedom is taken to represent the extreme vibration of the cutterhead under the corresponding working conditions. Finally, by comparing the fluctuation of the ultimate vibration amplitude of each type of cutterhead in the process of working condition conversion, the results are as follows: when the transition between homogeneous strata and composite strata is normal and there is no large turning and deviation correction, the vibration response of the two-part cutterhead is the smallest, and the two-part cutterhead is the best choice. Otherwise, the five-part cutterhead is the best choice, while the stability of the integrated cutterhead is the worst.

关键词： Cutterhead Working Condition Conversion Stability Type Selection of Cutterhead

旅游时间序列的季节性特征研究——以城市入境旅游为例

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旅游学刊 2015年第1期30卷 63-71页

作者：林德荣张军洲厦门大学管理学院福建厦门361005

国内学者在旅游时间序列的季节性特征方面具有广泛的研究,但多数是从纵向时间角度分析旅游时间序列自身较为外显的季节性特征,而对旅游时间序列自身相对较为隐性的季节性特征到目前为止鲜有研究。基于此,文章以城市入境旅游时间序列为例... 详细信息

国内学者在旅游时间序列的季节性特征方面具有广泛的研究,但多数是从纵向时间角度分析旅游时间序列自身较为外显的季节性特征,而对旅游时间序列自身相对较为隐性的季节性特征到目前为止鲜有研究。基于此,文章以城市入境旅游时间序列为例,从季节性单位根入手,通过分析杭州市入境旅游人天样本数据,获得杭州入境旅游时间序列的隐性季节特征。研究结果表明,杭州入境旅游人天数据时间序列是一个非平稳性的随机季节过程,其季节性特征显著,具有一个非季节性单位根以及5个季节性单位根。

关键词：旅游季节性季节性单位根 HEGY检验

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四缸双作用斯特林发动机平衡改进设计

哈尔滨工程大学学报 2014年第8期35卷 987-992页

作者：霍军周李涛张旭杨静路林大连理工大学机械学院辽宁大连116024 道依茨一汽(大连)柴油机有限公司辽宁大连116024

四缸U型传动机构是斯特林发动机输出功率的核心部件,其设计的合理与否直接与斯特林发动机系统运行的稳定性、效率、寿命密切相关。基于四缸U型传动机构的特点,建立了传动机构动平衡配重的理论模型,获得了曲轴及输出轴上配重的质量和相位... 详细信息

四缸U型传动机构是斯特林发动机输出功率的核心部件,其设计的合理与否直接与斯特林发动机系统运行的稳定性、效率、寿命密切相关。基于四缸U型传动机构的特点,建立了传动机构动平衡配重的理论模型,获得了曲轴及输出轴上配重的质量和相位;进而基于多体动力学仿真平台,建立了4缸双作用斯特林发动机传动机构动力学仿真模型,为更真实地模拟曲轴实际运行状态,采用哑元及万向铰连接方法建立了曲轴等效模型,采用虚拟油膜的方法建立了滑动轴承支撑等效模型。动力学仿真结果表明:相比原传动机构模型,改进后的传动机构输出轴、左曲轴和右曲轴速度波动系数分别降低了11.5%、36.8%和34.4%;输出轴质心振动位移均值降低了20.0%;基座承受的动载荷均值降低了23.4%;验证了改进方案可行性和有效性,为斯特林机传动机构的设计提供一定的理论依据。

关键词：斯特林发动机传动机构动平衡动力学仿真

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环状直流配电网故障测距方法

电力系统及其自动化学报 2021年第6期33卷 93-99,109页

作者：谢俊州吕飞鹏林婵娟四川大学电气工程学院成都610065 国网凉山供电公司电力调度控制中心西昌615000

直流线路发生故障后,为快速找到故障点,研究直流配电网的故障测距技术十分必要。文中在分析直流配电网故障特征的基础上,提出了一种基于故障暂态信息的高精度故障测距方法。该方法利用故障电容放电阶段的电流电压信息建立故障测距表达式... 详细信息

直流线路发生故障后,为快速找到故障点,研究直流配电网的故障测距技术十分必要。文中在分析直流配电网故障特征的基础上,提出了一种基于故障暂态信息的高精度故障测距方法。该方法利用故障电容放电阶段的电流电压信息建立故障测距表达式,然后对式中电流微分计算方法进行分析,提出了降低测距误差率的采样点选取方法,利用选取的点参与故障测距计算得到的结果精度较高。最后在PSCAD/EMTDC上进行故障仿真,并将录波数据导入到MATLAB进行计算,结果验证了方法的有效性。

关键词：直流配电网故障测距暂态信息电容放电电流微分计算

基于UG的新型病房病员转运床的建模设计与有限元分析

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机械设计与制造工程 2019年第1期48卷 31-34页

作者：王骞任俊州黄林李军佟林重庆交通大学机电与车辆工程学院重庆400000

利用UG和ANSYS软件,设计了一种新型病房病员转运床。首先依照医疗器械的国家标准,确定了转运车的外形尺寸,然后对转运床进行三维建模。对病人的基本情况(身高、体重等)做出假设,以简化装置的受力模型。利用ANSYS软件对装置承重部分进行... 详细信息

利用UG和ANSYS软件,设计了一种新型病房病员转运床。首先依照医疗器械的国家标准,确定了转运车的外形尺寸,然后对转运床进行三维建模。对病人的基本情况(身高、体重等)做出假设,以简化装置的受力模型。利用ANSYS软件对装置承重部分进行了有限元分析。由有限元分析结果可知,在选定材料的情况下,4个着力点处会产生局部的塑性变形,而其他部位的变形均在弹性变形范围。由此证明,在该假设条件下转运床是安全可靠的。

关键词：转运床有限元分析全参数化建模模块化设计