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生态环境视域下玉林华侨华人早期出国原因再探

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玉林师范学院学报 2024年第2期45卷 53-59页

作者：黄文波广西民族大学民族学与社会学学院广西南宁530006

既有研究中,对玉林华侨华人早期出国原因的探讨均基于政治、经济等相关因素。文章认为,清末民初时期,在气候条件和自然灾害等生态环境因素影响下,部分玉林华侨华人被迫选择迁徙国外谋求生存。因此,生态环境因素也是他们早期出国原因之一... 详细信息

既有研究中,对玉林华侨华人早期出国原因的探讨均基于政治、经济等相关因素。文章认为,清末民初时期,在气候条件和自然灾害等生态环境因素影响下,部分玉林华侨华人被迫选择迁徙国外谋求生存。因此,生态环境因素也是他们早期出国原因之一,应当考虑为当地人口向外流动中不可忽视的推动因素之一。

关键词：生态环境气候条件自然灾害玉林华侨华人

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分布驱动无人车在极限工况下的稳定跟踪控制

机械设计与制造 2024年第10期 126-132页

作者：严运兵黄博文唐学权田良宇武汉科技大学汽车与交通工程学院湖北武汉430065

针对分布式驱动无人车在低附着、高速的极限工况下行驶时偏离目标路径和失稳的现象,提出一种稳定-跟踪联合控制策略,策略包含路径跟踪控制和横向稳定控制,使无人车在提高跟踪精度的同时又使其稳定性得到保障。路径跟踪模块在汽车二自由... 详细信息

针对分布式驱动无人车在低附着、高速的极限工况下行驶时偏离目标路径和失稳的现象,提出一种稳定-跟踪联合控制策略,策略包含路径跟踪控制和横向稳定控制,使无人车在提高跟踪精度的同时又使其稳定性得到保障。路径跟踪模块在汽车二自由度模型的基础上,建立了最优LQR路径跟踪控制器,并引入前馈用以改善稳态误差,其次考虑误差变化的规律和路-车位置关系以及驾驶员预瞄模型,设计了改进的权重参数自适应LQR控制器;稳定性模块基于可以减小系统抖振的滑模模糊控制原理,并结合汽车稳定性参数的实际值与期望值的差值,求解出横摆力矩。其次在分配各轮转矩时建立约束条件,使得轮胎负荷率最小用以提升汽车的操纵稳定性。CarSim/Simulink仿真表明在高速、低附着的换道工况下,改进后的LQR控制器有效地改善跟踪误差,具有良好的鲁棒性。且在加入稳定性控制器后,横摆角速度与质心侧偏角的调节时间变短,极大改善了无人车在极限工况下的稳定性。

关键词：分布式驱动无人车自适应LQR控制极限工况跟踪横摆稳定性控制

基于F_(2:3)的单倍体群体对玉米株高进行QTL定位及GS选择

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玉米科学 2024年第7期32卷 7-13页

作者：许加波张昕航任子龙黄博文陈占辉吴鹏昊任姣姣新疆农业大学农学院乌鲁木齐830052

利用优良玉米自交系郑58和B73杂交构建的F2:3家系为材料,对其经过单倍体诱导系诱导获得的单倍体植株在多环境下对株高进行表型鉴定及遗传研究。结果表明,使用完备区间作图法(ICIM)共定位到8个与株高相关的QTL位点,分别位于1、4、5、7和1... 详细信息

利用优良玉米自交系郑58和B73杂交构建的F2:3家系为材料,对其经过单倍体诱导系诱导获得的单倍体植株在多环境下对株高进行表型鉴定及遗传研究。结果表明,使用完备区间作图法(ICIM)共定位到8个与株高相关的QTL位点,分别位于1、4、5、7和10号染色体,定位结果解释表型变异介于3.98%~21.04%。其中,qPH4-2在多个环境下被定位到,表型贡献率(Phenotypic variation expland,PVE)介于14%~21%,为主效QTL位点;另一主效位点qPH4-1所在的bin4.08区间包含候选基因GRMZM2G393337,可使细胞伸长受到抑制而导致矮化。对F2:3家系单倍体株高使用RRBLUP模型进行GS,5倍交叉验证平均预测精度为0.50。随着训练群体大小和标记数目的增加,预测精度会先增加随后趋于平缓。当训练群体占总体的60%或当SNP标记数目达到300时,即可得到较高的预测精度。

关键词：玉米单倍体株高 QTL 全基因组选择

A Note on Unification of Translational Shape Invariant Potential and Scaling Shape Invariant Potential

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Communications in Theoretical Physics 2005年第4X期44卷 619-621页

作者： huang bo-wen GU Zhi-Yu QIAN Shang-Wu Physics Department Capital Normal University Beijing 100037 China Physics Department Peking University Beijing 100871 China

This article puts forward a general shape invariant potential, which includes the translational shape invariant potential and scaling shape invariant potential as two particular cases, and derives the set of linear di... 详细信息

关键词： translational shape invariant potential scaling shape invariant potential

Phase Space Path Integral Method for Problem of Obtaining Propagator of a Particle with a Force Quadratic in Velocity

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Communications in Theoretical Physics 2006年第2期45卷 259-261页

作者： GU Zhi-Yu huang bo-wen QIAN Shang-Wu physics Department Capital Normal University Beijing 100037 China physics Department Peking University Beijing 100871 China

This article uses the phase space path integral method to find the propagator for a particle with a force quadratic in velocity. Two specific canonical transformations has been used for this purpose.

关键词： phase space path integral propagator canonical transformation

Effect of seepage-induced erosion on soil macropore structure

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Journal of Mountain Science 2023年第11期20卷 3402-3422页

作者： huang wen-bo huang Da GAO Yi-kang LIU Yang LI Zhao MENG Qiu-jie School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China. College of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China.

Internal erosion is one of the important factors causing geological *** microstructure of soil can change with seepage erosion,resulting in changes in the hydraulic and mechanical properties of the *** evolution of seepage erosion is investigated with X-ray computed tomography(CT)in this *** change in macropore structure characteristics during the seepage erosion test is quantified and the influence of seepage erosion on soil deformation is ***,a pore network model(PNM)is established for the specimens and the evolution of the connected pore size characteristics is *** results show that the macropore structure is significantly affected by seepage erosion,especially in terms of the porosity and pore geometry *** changes in macropore structure characteristics are most obvious in the lower part of the *** influence of seepage erosion on the pore size distribution(PSD)and soil deformation is heterogeneous and closely dependent on the spatial location of the ***,seepage erosion enhances macropore connectivity and has a directional impact on macropore *** findings can provide a reference for the theoretical modeling and numerical simulation of the seepage erosion and improve the understanding of the seepage erosion evolution in engineering practice.

关键词： Seepage erosion Heterogeneity Macropore structure Pore size distribution Microstructure CT scanning

A numerical method of combined SPF-MEM-LBM on the rockfall-induced surge and its application

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Journal of Mountain Science 2022年第1期19卷 167-183页

作者： MENG Qiu-jie SONG Yi-xiang huang Da huang Run-qiu ZHONG Zhu huang wen-bo LIU Yang School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China College of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

Rockfalls in reservoirs are prone to induce surges, posing a severe threat to passing vessels and facilities. A scheme combined Single-phase freesurface method(SPF), momentum exchange method(MEM), and Lattice boltzmann method(LBM) is proposed to predict the impact of rockfall-induced surges. First, the LBM-SPF model is used to simulate the motion of the free surface, and the MEM model is used to calculate the hydrodynamic force acting on rock mass. To address the incompatibility issue arising from the coupling of LBM-SPF model and MEM model, a correction scheme inside the solid is induced. The simulation results of the single particle and double particle sedimentation in cavity show the feasibility and accuracy of the method designed in this paper. Moreover, the validation experiments of Scott Russel’s wave generator show that the proposed scheme can simulate wave profile stably. The simulation results emphasize that the waves induced by rockfalls have a significant impact on the safe operation of the Laxiwa dam and the passing vessels in the reservoir.

关键词： Lattice boltzmann method Momentum exchange method Fluid solid coupling Rockfall induced surges Reservoir bank slope

Supersymmetry and Shape Invariance of Hartmann Potential and Ring-Shaped Oscillator Potential in the γ and θ Dimensions of Spherical Polar Coordinates

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Communications in Theoretical Physics 2002年第8期38卷 139-142页

作者： QIAN Shang-Wu huang bo-wen WANG De-Yun GU Zhi-Yu Physics Department Peking University Beijing 100871 China Physics Department Capital Normal University Beijing 100037 China Physics Department Capital Normal University Beijing 100037 China Physics Department Capital Normal University Beijing 100037 China

This article shows that in spherical polar coordinates, some noncentral separable potentials have super-symmetry and shape invariance in the r and θ dimensions, we choose Hartmann potential and ring-shaped oscillator astwo important examples, thus in principle the energy eigenvalues and energy eigenfunctions of such the potentials in ther and θ dimensions can be obtained by the method of supersymmetric quantum mechanics. Here we use an alternativemethod to get the required results.

关键词： Hartmann potential, ring-shaped oscillator potential, supersymmetric quantum mechanics, shapeinvariance, noncentral separable potential, spherical polar coordinates

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PEMFC热管理系统建模与控制策略研究

武汉理工大学学报 2024年第3期46卷 156-164页

作者：万昱肖纯易子淳刘岩黄文波武汉理工大学自动化学院武汉430070 国家能源氢能及氨氢融合新能源技术重点实验室佛山仙湖实验室佛山528200

以100 kW的质子交换膜氢燃料电池为研究对象,设计大小循环结构热管理系统,进行PEMFC电堆散热分析与关键部件选型,基于Amesim平台搭建热管理子系统一维模型并引入氢燃料汽车模型和驾驶员模型,降低了建模难度。基于该模型,设计模糊控制器... 详细信息

以100 kW的质子交换膜氢燃料电池为研究对象,设计大小循环结构热管理系统,进行PEMFC电堆散热分析与关键部件选型,基于Amesim平台搭建热管理子系统一维模型并引入氢燃料汽车模型和驾驶员模型,降低了建模难度。基于该模型,设计模糊控制器并采用鲸鱼优化算法优化其隶属度函数,通过控制散热风扇和冷却水泵的转速来调节PEMFC电堆的温度。同时,在自定义工况和NEDC工况下,进行Amesim/Simulink联合仿真分析,仿真结果表明:在两种工况下,改进后的模糊控制器控制性能更好,温度变化更平稳,热管理系统稳定性更好,同时在工况剧烈变化时,PEMFC电堆温度也会出现小幅度震荡。

关键词：大小循环结构模糊控制鲸鱼优化算法质子交换膜燃料电池热管理