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Coupled Time-Domain Investigation on a Vertical Axis Wind Turbine Supported on a Floating Platform

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Journal of Ocean University of China 2023年第2期22卷 365-376页

作者： cui jianhui ZHAI Yongjian GUO Ying DENG Wanru LIU Liqin Maritime College Tianjin University of TechnologyTianjin 300384China State Key Laboratory of Hydraulic Engineering Simulation and Safety School of Civil EngineeringTianjin UniversityTianjin 300072China

The dynamic responses of a floating vertical axis wind turbine(VAWT)are assessed on the basis of an aero-hydro-mooring coupled *** aerodynamic loads on the rotor are acquired with double-multiple stream tube ***-and second-order wave loads are calculated on the basis of 3D potential *** mooring loads are simulated by catenary *** coupled model is established,and a numerical code is programmed to investigate the dynamic response of the semi-submersible VAWT.A model test is then conducted,and the numerical code is validated considering the hydrodynamic performance of the floating *** responses of the floating VAWT are studied through the numerical simulation under the sea states of wind and regular/irregular *** effects of the second-order wave force on the motions are also *** show that the slow-drift responses in surge and pitch motions are significantly excited by the second-order wave ***,the effect of foundation motion on aerodynamic loads is *** normal and tangential forces of the blades demonstrate a slight increase due to the coupling effect between the buoy motion and the aerodynamic loads.

关键词： offshore wind power semi-submersible floating foundation vertical axis wind turbine numerical calculation model test

北京地区蒙古栎(Quercus mongolica)外生菌根真菌群落特征

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西北农业学报 2024年第7期33卷 1364-1374页

作者：赵誉涵孙佳琦孙静双崔建辉冷平生胡增辉国家林业草原古树健康与古树文化工程技术研究中心/园林学院北京农学院北京102206 城乡生态环境北京实验室北京102206 北京市房山区南梨园林场北京102425 北京市房山区大石窝集体林场北京102407 北京市乡村景观规划设计工程技术研究中心北京102206

为揭示北京地区蒙古栎(Quercus mongolica)外生菌根真菌群落特征,选取北京农学院林场、云蒙山国家森林公园和百花山国家级自然保护区3个蒙古栎山区自然分布地,以及奥林匹克森林公园和中关村森林公园2个平原引种地为采样地,采集土壤和生... 详细信息

为揭示北京地区蒙古栎(Quercus mongolica)外生菌根真菌群落特征,选取北京农学院林场、云蒙山国家森林公园和百花山国家级自然保护区3个蒙古栎山区自然分布地,以及奥林匹克森林公园和中关村森林公园2个平原引种地为采样地,采集土壤和生有外生菌根的蒙古栎根部样品,检测其土壤理化及酶活性指标,采用ITS高通量测序技术对其外生菌根真菌群落进行测定,初步分析真菌群落多样性与环境因子之间的相关性。结果表明,平原采样地和山区采样地的土壤特性存在明显差异,山区分布地的全氮、速效磷含量以及磷酸酶活性较高,而平原引种地的pH、全磷含量较高。测序后经过OTU注释和α多样性分析,发现绒盖牛肝菌属(Xerocomellus)、丝膜菌属(Cortinarius)、红菇属(Russula)、块菌属(Tuber)为北京地区蒙古栎主要外生菌根真菌类群,但各采样地的优势菌各不相同,并且平原采样地蒙古栎根部外生菌根真菌群落多样性指数低于山区采样地。真菌群落与环境因子相关性分析表明,土壤全氮含量、全磷含量、速效磷含量、碳氮比、磷酸酶活性、海拔、坡度等与真菌多样性关系密切。

关键词：蒙古栎外生菌根真菌真菌多样性土壤理化指标环境因子

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增建升船机恢复海河航运功能的设想

中国海事 2024年第2期 24-26页

作者：那博文崔建辉穆怀利天津理工大学天津300384 天津市杨柳青船厂天津300390

通过对海河通航及旅游业发展现状的分析,提出在保持二道闸现有功能和结构的前提下,可考虑在此处修建升船机,打通海河下游航道,使得游船可通过二道闸,实现海河全线通航,后续可带动海河沿岸服务产业和货运运输,以此促进天津航运经济发展。

关键词：二道闸升船机海河航运游船游览

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卫星导航定位课程基于证据启发的学习设计

地理空间信息 2024年第1期22卷 120-123页

作者：刘智敏刘尚国孔巧丽苏醒崔健慧山东科技大学测绘与空间信息学院山东青岛266590

核心素养是学生应具备的能适应社会和终身发展需要的关键能力和必备品格,实践创新是6大核心素养之一。随着“互联网+教育”的迅速发展,结合网络教育对卫星导航定位专业课程进行基于证据启发的学习设计,有益于培养学生的实践创新素养。... 详细信息

核心素养是学生应具备的能适应社会和终身发展需要的关键能力和必备品格,实践创新是6大核心素养之一。随着“互联网+教育”的迅速发展,结合网络教育对卫星导航定位专业课程进行基于证据启发的学习设计,有益于培养学生的实践创新素养。以提高工程实践能力为目标,通过线上线下混合式教学下翻转课堂的讨论式、启发式教学方法对该课程的专业知识进行关联、融合、贯通,进一步应用于解决工程实践问题。经过3轮以上的教学实践,通过对比传统式、混合式等不同教授—学习设计发现,混合式教学下基于证据启发的工程案例学习设计有助于培养学生解决复杂工程问题的能力以及工程实践创新能力。

关键词：《卫星导航定位原理与应用》混合式教学基于证据启发的学习设计工程实践能力

Strategies for improving extraction capacity through preorganization structure:A novel 5,6-bicyclicmalonamide extractant(THPPD)

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Journal of Rare Earths 2024年第4期42卷 768-774页

作者： Miaomiao Zhang Zhen Yang Yuhua cui jianhui Su Heng Zhao Chengjin Xu Xiaolei Liu Guoxin Sun Xiujing Peng Yu cui School of Chemistry and Chemical Engineering University of JinanJinan250022China Institute for Smart Materials&Engineering University of JinanJinan250022China Shandong Institute for Food and Drug Control Jinan250101China

Rational design of extractant structure to improve the extraction and separation capacity of rare earth elements(REEs)is a long-standing ***,a new strategy was proposed to improve the stability of the chelating structure formed by malonamide and *** stability of the chelating structure is greatly improved by using a double-ring framework structure which makes the two carbonyl groups of malonamide unable to rotate freely and both of them point to the metal ion *** benzyl groups were used to construct the hydrophobicity of the extractant and the organic shell of the extracted ***-pyrrolo-pyridine-dione(THPPD)was designed and *** structure reduces the energy consumed by rotating carbonyl group in the coordination with metal ions and then improves the extraction ability of *** crystal structure was preorganized as expected,with the two carbonyls pointing in a favorable coordination direction to the structural complement of the metal *** extraction behaviors of REEs with THPPD in a nitric acid medium were *** with N,N’-dibenzyl-N,N’-dimethylmalonamide(DBDM-MA)with a chain structure,the extraction capacity of THPPD is 360 times higher than that of DBDM-MA at 5.0 mol/L sodium ***,the binding energy and Gibbs free energy were investigated by density functional theory(DFT)in conjunction with the *** theoretical results show that THPPD has more effective interaction with Pr(NO_(3))3 than *** construction of chelating groups conformation is a worthy direction to improve the coordination ability and even selectivity of extractant.

关键词： Rare earth elements Extraction separation 5,6-bicyclicdiamide extractant

Influence of the penetration of adjacent X-section cast-in-place concrete(XCC)pile on the existing XCC pile in sand

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 557-572页

作者： Peng ZHOU jianhui XU Changjie XU Guangwei CAO Jie CUP Xuanming DING School of Civil Engineering and Architecture State Key Laboratory of Performance Monitoring and Protecting of Rail Transit InfrastructureEast China Jiaotong UniversityNanchang330013China Guangdong Key Laboratory of Earthquake Engineering and Application Technology Earthquake Engineering Research&Test CenterGuangzhou UniversityGuangzhou510006China Key Laboratory of New Technology for the Construction of Cities in Mountain Areas College of Civil EngineeringChongqing UniversityChongqing400045China Zijin School of Geology and Mining Fuzhou UniversityFuzhou350116China

A series of small-scale 1g X-section cast-in-place concrete(XCC)pile-penetration model tests were conducted to study the effects of soil density and pile geometry on the lateral responses of an existing pile and the variations in surrounding soil *** results showed that the bending patterns of existing XCC piles varied with penetration *** lateral response of the existing pile was sensitive to the change in relative density and pile *** example,the bending moment of the existing pile increased along with these *** development of the radial stressσ′r/σ′v0 of the soil around an existing pile showed different trends at various depths during the penetration of the adjacent ***,the change in radial stress during the penetration of the XCC pile did not exhibit the“h/R effect”that was observed in the free-field soil,due to the shielding effect of the existing *** peak value of radial stressσ′r_max/σ′v0 decreased exponentially as the radial distance r/R *** attenuation ofσ′r_max/σ′v0 with r/R in the loose sand was faster than in the medium-dense or dense ***σ′r_max/σ′v0 at the same soil location increased with the cross-section geometry parameter.

关键词： X-section cast-in-place concrete(XCC)pile Test Penetration Sand Lateral response Radial stress

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北斗区域星座对相对定位精度的影响分析

武汉大学学报（信息科学版） 2016年第8期41卷 1107-1112页

作者：唐卫明崔健慧惠孟堂武汉大学卫星导航定位技术研究中心湖北武汉430079

首先介绍了北斗系统的区域星座特点,然后从相对定位几何精度因子(relative dilution of precision,RDOP)和定位误差两方面进行精度分析,初步得出了北斗相对定位精度与区域星座的关系。理论分析和实验结果都表明,在我国范围内采用北斗卫... 详细信息

首先介绍了北斗系统的区域星座特点,然后从相对定位几何精度因子(relative dilution of precision,RDOP)和定位误差两方面进行精度分析,初步得出了北斗相对定位精度与区域星座的关系。理论分析和实验结果都表明,在我国范围内采用北斗卫星导航系统进行短基线相对定位时,其东西方向定位精度优于南北、高程方向;南北方向与高程方向的定位误差呈负相关;北斗相对定位精度随纬度增加而降低;与GPS相比,北斗相对定位在南北方向精度略差;载波相位相对定位精度受北斗区域星座的影响略大于单频伪距差分。

关键词：北斗卫星导航系统区域星座相对定位 RDOP 定位误差

Accuracy analysis of error compensation in the ionospheric model of BDS broadcasting based on ABC-BP neural network

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Accuracy analysis of error compensation in the ionospheric m...

Effect of Troposphere Parameter Estimation on BDS PPP

第十三届中国卫星导航年会

作者： Qiang Li Xing Su Xin Xie Chunyan Tao jianhui cui Hanlin Chen Zhimin Liu College of Geodesy and Geomatics Shandong University of Science and Technology Key Laboratory of Geomatics and Digital Technology of Shandong Province Shandong University of Science and Technology Beijing Satellite Navigation Center

In GNSS navigation and positioning, ionospheric delay error is one of the sources of error that cannot be ignored. The BDS Klobuchar（BDSKlob） and BDGIM model parameters are broadcast by the BDS Navigation Satellite System in the broadcast ephemeris to correct for ionospheric delay errors, which can meet the basic navigation and positioning needs of users. However, in the face of the growing demand for autonomous positioning and navigation accuracy, it is necessary to further improve the accuracy of the model and reduce the impact of the space environment on positioning. In this paper, a Back Propagation（BP） neural network optimized by Artificial Bee Colony Algorithm（ABC） is used to compensate for the error prediction of the BDS broadcast ionosphere model from 7 to 13 September 2021. For BDSKlob and BDGIM, a number of grid points in the Chinese region and worldwide are selected for experimental analysis. BDSKlob and BDGIM respectively selected several grid points in China and the world for experimental analysis. The results show that the prediction compensation of the BDS broadcast ionosphere model errors using ABC-BP neural network can achieve better accuracy results. For BDSKlob, the model correction rate improved to 81.66% in China after using the predicted values to compensate for the model values. For BDGIM, the accuracy was significantly improved in the global mid and high latitudes, with model correction rates of 74.25%, 82.05% and 82.13% for the high, mid and low latitudes respectively after compensation.

关键词： BDS Artificial bee colony algorithm Neural Networks Klobuchar BDGIM Error compensation

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Effect of Troposphere Parameter Estimation on BDS PPP