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弹性支承边界条件对桥梁共振与消振的影响机理分析

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土木工程学报 2024年第6期57卷 13-25页

作者：陈雷杨永斌王志鲁刘志勇姚华重庆大学重庆400045 重庆市交通工程质量检测有限公司重庆400067

铁路桥梁服役过程中,因支座病害和冲刷等作用,桥梁端部约束常发生弱化。该文旨在理论解析边界支承条件及其变化对桥梁动力特性及共振与消振条件的影响机理。文章首先提出考虑左右支承刚度不等的弹性支承梁振型的简化表达,建立了移动连... 详细信息

铁路桥梁服役过程中,因支座病害和冲刷等作用,桥梁端部约束常发生弱化。该文旨在理论解析边界支承条件及其变化对桥梁动力特性及共振与消振条件的影响机理。文章首先提出考虑左右支承刚度不等的弹性支承梁振型的简化表达,建立了移动连续荷载作用下弹性支承梁自由振动的理论闭合解;然后推导考虑左右支承刚度不等的桥梁共振与消振条件,理论解析桥梁-支承刚度比(刚度比)、左右支承刚度不等比(刚度不等比)的影响机理;最后通过数值模拟验证理论解的准确性,并参数化分析支承条件参数对桥梁动力特性及共振与消振条件的影响规律。研究结果表明:(1)弹性支撑梁的频率随弹性支承的刚度比和刚度不等比增大而减小;(2)弹性支承梁的共振与外部消振速度参数与简支梁一致,但共振与外部消振速度降低,更易激发共振与外部消振;(3)支承条件对桥梁内部消振条件影响大,当左右支承刚度相等时,存在唯一内部消振条件,否则不发生内部消振;(4)当桥梁支承弱化或者两侧刚度不等时,基于简支梁的最佳跨长对共振的消除效应将逐渐失效;(5)阻尼有利于抑制桥梁共振幅值,对外部消振存在微小的非零值“阻尼泄露效应”;(6)当两侧支承刚度不相等时,桥梁最大响应位置偏离桥梁跨中,需在桥梁检测时关注。

关键词：铁路桥梁弹性支承梁共振消振不等支承

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基于生成对抗网络的非织造布二维图像重建

现代纺织技术 2024年第1期32卷 54-63页

作者：王志禄侯珏杨阳刘正浙江理工大学服装学院杭州310018 浙江理工大学浙江省服装工程技术研究中心杭州310018 武汉纺织大学武汉纺织服装数字化工程技术研究中心武汉430073 浙江理工大学国际时装技术学院杭州310018

非织造布纤维结构的准确表征是其性能分析的重要基础。为了解决基于近似模拟的表征结果中纤维形态、结构与真实样本不一致的问题,提出了一种基于生成对抗网络的非织造布二维图像重建方法。使用全自动光学显微镜对非织造布图像进行抓取,... 详细信息

非织造布纤维结构的准确表征是其性能分析的重要基础。为了解决基于近似模拟的表征结果中纤维形态、结构与真实样本不一致的问题,提出了一种基于生成对抗网络的非织造布二维图像重建方法。使用全自动光学显微镜对非织造布图像进行抓取,并在此基础上构建纤维生成对抗网络(Fiber generation adversarial network,FGAN)对图像样本进行建模。针对高分辨率图像重建时存在的失真问题,采用多尺度训练策略,同时引入权重多样性损失。采用图像质量评估指标FID作为实验评价指标,分别与DCGAN、WGAN-GP、BEGAN、PROGAN等生成模型进行对比实验。结果表明:FGAN重建的非织造布图像质量更高;消融实验证明,多尺度训练策略与权重多样性损失函数中FID数值分别降低24.52%、20.31%。FGAN模型的提出,使非织造布结构分析摆脱对近似模拟方法的依赖,提供了准确的纤维分布信息,对非织造布的质量评估、性能优化等应用具有重要意义。

关键词：非织造布孔隙生成对抗网络多样性损失图像重建

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TA33钛合金舵机支架锻造成形工艺

锻压技术 2023年第7期48卷 57-63页

作者：王志录施文鹏车安达江西景航航空锻铸有限公司江西景德镇333000

采用DEFROM有限元数值模拟软件与试验相结合的方法对TA33钛合金舵机支架锻造成形的过程进行研究。研究结果表明:通过分析不同的锻造毛坯(圆棒料;圆棒料镦粗至280 mm,后拍扁至140 mm;340 mm×250 mm×95 mm的方形毛坯)、始锻温度(989~101... 详细信息

采用DEFROM有限元数值模拟软件与试验相结合的方法对TA33钛合金舵机支架锻造成形的过程进行研究。研究结果表明:通过分析不同的锻造毛坯(圆棒料;圆棒料镦粗至280 mm,后拍扁至140 mm;340 mm×250 mm×95 mm的方形毛坯)、始锻温度(989~1019℃)以及锻造锤数(1~3锤)的有限元数值模型,得到最优的锻造参数为:锻造毛坯选用340 mm×250 mm×95 mm方形毛坯,始锻温度为999℃,锻造锤数为2锤。最后通过工艺试验的结果可以看出,实际锻造生产与DEFROM有限元数值模拟结果吻合良好,通过最优锻造工艺参数生产的锻件的显微组织、力学性能数据、疲劳性能数据均能满足预期要求,且有一定的富余量。

关键词： TA33钛合金舵机支架锻造显微组织始锻温度锻造锤数

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生态市建设应坚持四个统一

理论前沿 2006年第18期483卷 44-45页

作者：王志禄中共烟台市委党校

要全面推进生态市建设,需要从理论与实践相结合的高度,认真坚持四个统一:建设规划和推进行动的统一;各行政区域和部门的协调统一;干部政绩考核与生态指标考核的统一;城乡的协调统一。

关键词：生态市建设协调发展效果与经验

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人与环境关系的理性分析

理论前沿 2007年第11期 19-20页

作者：王志禄烟台市委党校

环境是人与自然、人与社会相互作用的产物,是自然环境与社会环境构成的复杂系统;自然环境和社会环境相互结合,共同影响着人的活动;环境的优化,是主体自觉与客体约束的统一过程,是一个全面的系统工程。

关键词：环境主体优化

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： wang Yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

Light People: Professor Fanglin Bao and his cover story

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Light(Science & Applications) 2024年第6期13卷 1015-1020页

作者： Ji wang School of Science Westlake UniversityHangzhouZhejiangPR China

Qu Yuan,a renowned ancient Chinese poet,once pondered in his work Heavenly Inquiry:“If the sun’s light is absent,from where does the radiance of the Hero Flower emanate?”The ability to see clearly in the darkest of nights has long been a sought-after magical power by *** holds not only immense technological significance for computer vision and remote sensing but also profound implications for transcending the dichotomy between day and night in our daily *** Fanglin Bao from Westlake University has made significant breakthroughs in this field,bringing us closer to a world where we can transform night into *** groundbreaking research on Heat-Assisted Detection and Ranging(HADAR)and night vision was featured as the cover story in Nature on July 26,2023.

关键词： bringing breakthrough holds