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Fluid Resonance Between Twin Floating Barges with Roll Motion Under Wave Action

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China Ocean Engineering 2021年第6期35卷 789-801页

作者： LI Shu TENG bin State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The wave-induced fluid resonance between twin side-by-side rectangular barges coupled with the roll motion of the twin barges is investigated by both numerical simulation and physical model test.A 2D numerical wave flume,based on an open source computational fluid dynamics(CFD)package OpenFOAM,is applied for the numerical *** numerical validations and convergent verifications,the characteristics of the fluid resonance in the gap between the twin rolling side-by-side barges are *** resonant frequency of the oscillating fluid in the gap between the twin rolling barges decreases compared with that between the twin fixed ***,the twin barges roll in the opposite directions,and their equilibrium positions lean oppositely with respect to the initial vertical direction.A physical model test is carried out for a further investigation,in which the twin barges are set oppositely leaning and *** the present experimental results,a linear decrease of the resonant frequency with the increasing leaning angle is *** with the numerical results,the deflection of the equilibrium positions of the twin barges is a relevant factor for the resonant ***,the effects of the gap width and incident wave height on the fluid resonance coupled with roll motion are examined.

关键词： fluid resonance in a narrow gap roll motion of the twin barges OpenFOAM

基于模糊认知图的智能汽车驾驶权交互决策建模方法

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科学技术与工程 2024年第25期24卷 10964-10973页

作者：陈怿淳靳慧斌刘希中国民航大学交通科学与工程学院天津300300

针对人机共驾中的由自动驾驶接管到驾驶人接管切换的动态问题,提出一种基于模糊认知图(fuzzy cognitive map,FCM)的驾驶权交互决策模型。首先分别分析影响驾驶风险的车辆和人的动态风险因素,并选取车距、加速度、方向盘转向熵、驾驶员... 详细信息

针对人机共驾中的由自动驾驶接管到驾驶人接管切换的动态问题,提出一种基于模糊认知图(fuzzy cognitive map,FCM)的驾驶权交互决策模型。首先分别分析影响驾驶风险的车辆和人的动态风险因素,并选取车距、加速度、方向盘转向熵、驾驶员眼动信息、心脑电波信息等相关影响指标构建基于FCM的车辆动态风险模型与人的动态风险模型,再结合环境因素,车辆状况以及驾驶员水平构建基于FCM的驾驶员交互决策模型。为降低对专家知识的依赖,运用基于实数编码的遗传算法(real coded genetic algorithm,RCGA)对模型进行优化,进一步提高模型决策的准确性。仿真结果表明,经RCGA优化后模型适应度值达到0.979,可见该模型能够较好地应对动态、复杂的驾驶环境。

关键词：交通运输工程模糊认知图驾驶权交互直觉模糊集实数编码遗传算法

Analysis of Mode Interaction in Ultra-low Frequency Oscillation Based on Trajectory Eigenvalue

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Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1208-1220页

作者： Yusheng Xue Zijun bin State Grid Electric Power Research Institute Nanjing 211106China the School of Electrical Engineering Shandong UniversityJinan 250061China

Complex phenomena such as prolongedly undamped ultra-low frequency oscillation(ULFO)and eigenmode re-excitation are observed in the simulations of hydroelectric power *** are put on nonlinearities and mode interactions,which cannot be analyzed by traditional eigen-analysis *** order to investigate the mechanism of the evolvement of the nonlinear dynamic process in ULFO,this paper proposes a method to analyze the mode interactions ***,a disturbed trajectory is decoupled into a set of time-varying ***,transfer matrices of eigenmodes are extracted along the ***,consecutive sequences of eigenvalues and trajectories of components are formed by a proposed *** on the decoupled components and transfer matrices,the mechanisms of mode interactions and inheritance relationships between eigenmodes are *** causes and developments of the above complex phenomena are revealed by the proposed method in a test two-machine ***,the accuracy of the eigenmode matching technique is verified in the New England system.

关键词： Eigenmode matching hydroelectric power system mode interaction trajectory eigenvalue ultra-low frequency oscillation

旅游型传统村落用地与空间格局演变微尺度分析——以陕西省礼泉县袁家村为例

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地域研究与开发 2024年第1期43卷 174-180页

作者：张斌郭冰玉岳士俊西安建筑科技大学艺术学院西安710055 西安建筑科技大学建筑学院西安710055

以陕西省礼泉县袁家村为例,基于Google Earth高精度遥感图像,运用参与式乡村评估、ArcGIS空间分析、空间句法等方法分析乡村旅游发展中村庄用地功能及村庄空间格局的演变,探讨旅游干预对村庄空间格局的影响。结果表明:(1)2002—2022年... 详细信息

以陕西省礼泉县袁家村为例,基于Google Earth高精度遥感图像,运用参与式乡村评估、ArcGIS空间分析、空间句法等方法分析乡村旅游发展中村庄用地功能及村庄空间格局的演变,探讨旅游干预对村庄空间格局的影响。结果表明:(1)2002—2022年袁家村空间格局发生明显变化,表现为土地利用类型由村民生活生产主导转变为旅游发展所需,致使村庄空间结构由村民居住空间为中心的单核心放射状转向旅游空间为主的多核心密集型;(2)乡村旅游促使空间关系网络趋向复杂化,同时在土地功能细碎化过程中村庄交通空间的稳定性和空间结构主导性凸显;(3)袁家村空间格局演变受市场需求和政府调控等多方面因素推动,村民的积极响应和空间功能的理性更新是其中关键作用力。

关键词：乡村旅游传统村落用地演变空间格局陕西省礼泉县袁家村

基于MOSASAUR程序的中子-光子输运堆芯释热率计算方法研究

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核动力工程 2024年第3期45卷 37-44页

作者：胡馗马续波王连杰张斌赵晨张腾陈义学华北电力大学核科学与工程学院北京102206 中国核动力研究设计院核反应堆系统设计技术重点实验室成都610213

为了准确计算快堆堆芯中所有裂变材料与非裂变材料释热,并精细考虑中子、光子、电子在堆芯中的能量沉积,以提高快堆堆芯释热率计算精度。本文基于确定论两步法研究并实现了中子-光子输运堆芯释热率计算方法,通过求解裂变源中子输运方程... 详细信息

为了准确计算快堆堆芯中所有裂变材料与非裂变材料释热,并精细考虑中子、光子、电子在堆芯中的能量沉积,以提高快堆堆芯释热率计算精度。本文基于确定论两步法研究并实现了中子-光子输运堆芯释热率计算方法,通过求解裂变源中子输运方程和固定源光子输运方程得到中子和光子注量率,基于比释动能(KERMA)因子方法计算瞬发中子和瞬发光子释热率,利用比例因子方法计算缓发光子产生矩阵,在MOSASAUR程序内通过内耦合方式实现了快堆中子-光子输运和堆芯释热率计算。计算铅铋快堆RBEC-M基准题的功率分布并与蒙特卡罗程序计算结果进行对比,燃料组件总功率相对偏差在±4%以内,非燃料组件总功率相对偏差在±10%以内,所有组件光子功率相对偏差在±10%以内。因此,本文研究的中子-光子输运堆芯释热率计算方法对快堆堆芯释热计算具有较高精度。

关键词：中子-光子输运比释动能(KERMA)因子快堆缓发光子高阶光子输运

Probing the flavor-specific scalar mediator for the muon(g-2)deviation, the proton radius puzzle and the light dark matter production

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Science China(Physics,Mechanics & Astronomy) 2022年第3期65卷 39-48页

作者： bin Zhu Xuewen Liu Department of Physics Yantai UniversityYantai 264005China

Flavor-specific scalar bosons exist in various Standard Model extensions and couple to a single generation of fermions via a global flavor symmetry breaking mechanism. Given this strategy, we propose a Me V flavor-specific scalar model in dimension-5 operator series, which explains the muon g-2 anomaly and proton radius puzzle by coupling with the muon and down-quark at the same time. The framework is consistent with the null result of high-intensity searches. Specifically, the supernova constraints for muon couplings become weakened by including the contribution of down-quark interaction. The parameter space for explaining muon g-2 discrepancy is available when 10% energy deposition is required in the energy explosion process in the supernova,but this is ruled out by the 1% energy deposition requirement. We also investigate the searches for mediator and dark matter and the resulting constraints on viable parameter space such as nuclear physics constraints, direct detection for light boosted dark matter, and possible CMB constraints. When compared with conventional dark matter production, light dark matter production has two additional modifications: bound state formation and early kinetic equilibrium decoupling. We are now looking into the implications of these effects on the relic density of light dark matter.

关键词： muon g-2 proton radius puzzle DM relic density precision calculation

Association between the infection probability of COVID-19 and ventilation rates:An update for SARS-CoV-2 variants

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Building Simulation 2023年第1期16卷 3-12页

作者： Hui Dai bin Zhao Departmentof Building Science School of ArchitectureTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Indoor Air Quality Evaluation and Control Tsinghua UniversityBeijing 100084China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the cause of the current coronavirus disease 2019(COVID-19)pandemic,is ***,the risk of airborne transmission in confined spaces may be higher,and corresponding precautions should be ***,we obtained the quantum generation rate(q)value of three SARS-CoV-2 variants(Alpha,Delta,and Omicron)for the Wells-Riley equation with a reproductive number-based fitted approach and estimated the association between the infection probability and ventilation *** q value was 89–165 h^(−1)for Alpha variant,312–935 h^(−1)for Delta variant,and 725–2,345 h^(−1)for Omicron *** ventilation rates increased to ensure an infection probability of less than 1%,and were 8,000–14,000 m^(3)h^(−1),26,000–80,000 m^(3)h^(−1),and 64,000–250,000 m^(3)h^(−1)per infector for the Alpha,Delta,and Omicron variants,*** the infector and susceptible person wore N95 masks,the required ventilation rates decreased to about 1/100 of the values required without masks,which can be achieved in most typical *** air purifier was ineffective for reducing transmission when used in scenarios without *** prolonged exposure time in confined spaces remains critical in reducing the risk of airborne transmission for highly contagious SARS-CoV-2 variants.

关键词： COVID-19 SARS-CoV-2variants mask ventilation air purifier

Innovative Thin-Walled Structure with Transverse Negative Poisson’s Ratio for High-Performance Crashworthiness

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Acta Mechanica Solida Sinica 2023年第1期36卷 34-44页

作者： bin Wang Yongtao Sun Tianjin Key Laboratory of Soft Soils and Engineering Environment Tianjin Chengjian UniversityTianjin 300384China Department of Mechanics and Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin UniversityTianjin 300350China

In this paper,an innovative type of thin-walled structures,the convex-concave honeycomb columns(CCHCs)with transverse negative Poisson’s ratio(NPR),is proposed for energy absorbers by replacing the cell walls of square honeycomb lattice columns with sine-shaped or zigzag-shaped walls of equal *** simulations show that,under axial impact,contrary to the conventional square honeycomb columns of equal mass,the transverse cross section of NPR CCHC shrinks inward,making the cell walls of CCHC contact and interact sufficiently with each other and thus dissipate the impact energy much more *** suitably adjusting the transverse NPR,the CCHC can have the combined advantages of effective total energy absorption,high specific energy absorption and low maximum peak crushing *** research of this paper provides a new strategy for the design of high-performance energy absorbers widely used in the engineering fields of vehicle engineering,aerospace engineering etc.

关键词： Energy absorbers Convex-concave honeycomb columns(CCHC) Transverse negative Poisson’s ratio Axial impact High-performance crashworthiness

运动通过调节骨自噬途径防治骨质疏松症的作用及可能机制

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生物化学与生物物理进展 2024年第7期51卷 1589-1603页

作者：代新宇李斌靳丹衣雪洁黄睿奇高海宁沈阳体育学院运动健康学院沈阳110115 沈阳体育学院运动训练学院沈阳110115 沈阳体育学院运动与健康研究中心沈阳110115

自噬(autophagy)是一种溶酶体降解途径,可调节多种骨细胞(包括成骨细胞、骨细胞和破骨细胞)的增殖、分化和凋亡功能,深度参与骨重塑过程。近年来,自噬在骨质疏松症及相关骨代谢疾病进程中所发挥的作用越来越受到重视,已成为该领域的研... 详细信息

自噬(autophagy)是一种溶酶体降解途径,可调节多种骨细胞(包括成骨细胞、骨细胞和破骨细胞)的增殖、分化和凋亡功能,深度参与骨重塑过程。近年来,自噬在骨质疏松症及相关骨代谢疾病进程中所发挥的作用越来越受到重视,已成为该领域的研究热点。总结已有研究发现,衰老、氧化应激、雌激素缺乏和糖皮质激素治疗等因素会导致自噬活动异常,破坏骨重塑平衡,诱发骨质疏松。运动作为防治骨质疏松症的有效手段,可提高骨生物力学性能、增加骨密度,然而目前研究对于运动、骨自噬、骨质疏松之间的关系仍不清晰,运动通过骨自噬途径改善骨质疏松症可能成为一种新的分子调节机制。基于此,本文综述了运动防治骨质疏松症过程中骨细胞的自噬变化,以期揭示自噬在运动改善骨质疏松症中的作用及可能分子机制,为从自噬角度探寻防治骨质疏松症的临床干预手段提供参考。

关键词：骨质疏松症自噬运动哺乳动物雷帕霉素靶蛋白单磷酸腺苷活化蛋白激酶