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ELASTIC WAVE LOCALIZATION IN TWO-DIMENSIONAL PHONONIC CRYSTALS WITH ONE-DIMENSIONAL QUASI-PERIODICITY AND RANDOM DISORDER

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Acta Mechanica Solida Sinica 2008年第6期21卷 517-528页

作者： Ali Chen yuesheng wang Guilan Yu Yafang Guo Zhengdao wang Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China School of Civil Engineering Beijing Jiaotong University Beijing 100044 China

The band structures of both in-plane and anti-plane elastic waves propagating in two-dimensional ordered and disordered （in one direction） phononic crystals are studied in this paper. The localization of wave propagation due to random disorder is discussed by introducing the concept of the localization factor that is calculated by the plane-wave-based transfer-matrix method. By treating the quasi-periodicity as the deviation from the periodicity in a special way, two kinds of quasi phononic crystal that has quasi-periodicity （Fibonacci sequence） in one direction and translational symmetry in the other direction are considered and the band structures are characterized by using localization factors. The results show that the localization factor is an effective parameter in characterizing the band gaps of two-dimensional perfect, randomly disordered and quasi-periodic phononic crystals. Band structures of the phononic crystals can be tuned by different random disorder or changing quasi-periodic parameters. The quasi phononic crystals exhibit more band gaps with narrower width than the ordered and randomly disordered systems.

关键词： phononic crystal quasi phononic crystal disorder localization factors plane-wavebased transfer-matrix method periodic average structure

ZIF-derived Co–N–C ORR catalyst with high performance in proton exchange membrane fuel cells

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Progress in Natural Science:Materials International 2020年第6期30卷 855-860页

作者： Ruixiang wang Pengyang Zhang Yucheng wang yuesheng wang Karim Zaghib Zhiyou Zhou State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials College of Chemistry and Chemical Engineering Xiamen University Center of Excellence in Transportation Electrificationand Energy Storage Hydro Québec

Metal and nitrogen-doped carbon(M-N-C) materials have been considered as the most promising non-precious metal oxygen reduction(ORR) catalysts to replace expensive Pt catalysts. Due to high Fenton catalytic activity of Fe element and the resulting instability, Co-based N–C(Co–N–C) catalysts without Fenton catalytic activity should be a worthier ORR catalyst being explored. Although the high ORR activity of Co–N–C catalyst has been demonstrated in aqueous half-cell tests, their performance under PEMFC working condition is still far away from that of state-of-the-art Fe–N–C catalysts. In this study, a high-performance Co–N–C catalyst was synthesized by one-step pyrolyzing Co-doped ZIF-8(zeolitic imidazolate framework-8) particles in-situ grown on the highsurface-area KJ600 carbon black with high electronic conductivity. The resulting Co–N–C catalyst exhibited high intrinsic ORR activity, fast mass transfer rate and high electronic conductivity, and thus yielded a remarkable peak power density of 0.92 W cm-2in H2–O2PEMFC, which is comparable to state-of-the-art Fe–N–C *** strategy is helpful to synthesize highly active M-N-C ORR catalysts with improved mass transfer and electric conductivity.

关键词： Non-precious metal electrocatalysts Fuel cell Oxygen reduction Co-based catalyst ZIF-8

WAVE LOCALIZATION IN RANDOMLY DISORDERED PERIODIC PIEZOELECTRIC RODS WITH INITIAL STRESS

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Acta Mechanica Solida Sinica 2008年第6期21卷 529-535页

作者： Yize wang Fengming Li Kikuo Kishimoto yuesheng wang Wenhu Huang P.O. Box 137 School of Astronautics Harbin Institute of Technology Harbin 150001 China Department of Mechanical Sciences and Engineering Tokyo Institute of Technology 2-12-1 O-okayama Meguro-ku Tokyo 152-8552 Japan Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China

The elastic wave localization in disordered periodic piezoelectric rods with initial stress is studied using the transfer matrix and Lyapunov exponent method. The electric field is approximated as quasi-static. The effects of the initial stress on the band gap characteristics are investigated. The numerical calculations of localization factors and localization lengths are performed. It can be observed from the results that the band structures can be tuned by exerting the suitable initial stress. For different values of the piezoelectric rod length and the elastic constant, the band structures and the localization phenomena are very different. Larger disorder degree can lead to more obvious localization phenomenon.

关键词： piezoelectric phononic crystal initial stress random disorder localization factor,localization length

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船舶行业射线检测作业安全研究

无损探伤 2024年第1期48卷 39-42页

作者：曾鸿飞王跃生杨杰上海外高桥造船有限公司上海200137

船舶行业是衡量一个国家工业水平的标志之一,其作业安全管理是行业健康发展的重要组成部分。射线作业现场存在辐射安全问题,从辐射环境管理的角度,提出了射线现场探伤工作中辐射安全管理的技术和措施。射线辐射安全是安全管理的一部分,... 详细信息

船舶行业是衡量一个国家工业水平的标志之一,其作业安全管理是行业健康发展的重要组成部分。射线作业现场存在辐射安全问题,从辐射环境管理的角度,提出了射线现场探伤工作中辐射安全管理的技术和措施。射线辐射安全是安全管理的一部分,其具有作业环境差、辐射风险高、事故伤害大等特点,必须在安全管理体系和能力建设上下功夫,利用信息化技术,提升安全管理水平。

关键词：船舶射线检测安全

Nonlinear vibration of edged cracked FGM beams using differential quadrature method

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Science China(Physics,Mechanics & Astronomy) 2012年第11期55卷 2114-2121页

作者： KE LiaoLiang wang yuesheng YANG Jie KITIPORNCHAI Sritawat ALAM Firoz Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China School of Aerospace Mechanical and Manufacturing EngineeringRMIT UniversityPO Box 71BundooraVictoria 3083Australia Department of Building and Construction City University of Hong KongKowloonHong KongChina

This paper investigated the nonlinear vibration of functionally graded beams containing an open edge crack based on Timoshenko beam *** cracked section is modeled by a massless elastic rotational *** is assumed that material properties follow exponential distributions through the beam *** differential quadrature(DQ) method is employed to discretize the nonlinear governing equations which are then solved by a direct iterative method to obtain the nonlinear vibration frequencies of beams with different boundary *** effects of the material gradient,crack depth and boundary conditions on nonlinear free vibration characteristics of the cracked FGM beams are studied in detail.

关键词： functionally graded materials (FGMs) Timoshenko beam edge crack nonlinear vibration DQ method

Fire Monitoring System Based on SVM

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Fire Monitoring System Based on SVM

第36届中国控制会议

作者： yuesheng wang Mengyan Chen Schoole of Mathematics Automation Hangzhou Dianzi University

ISBN: (纸本)9781538629185

The occurrence of fire has a huge threat to people’s life,therefore,in order to improve the quality of people’s lives,we combines the support vector machine which is hot in recent years with the problem of home fire *** a new method based on ensemble empirical mode decomposition and support vector machine is *** results show that EEMD-SVM combination forecasting method has high accuracy for fire forecasting.

关键词： Support Vector Machines fire forecasting ensemble empirical mode decomposition EEMD

来源： cnki会议评论

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智能电网大数据分析

电气传动自动化 2024年第1期46卷 43-46页

作者：汪悦生何怡燕贾晓张宁国网安徽省电力有限公司安庆供电公司安徽安庆246000

本文介绍了“大数据”,特别是智能电网中的大数据。大量数据(大数据)包含大量信息,然而,由于大数据的一些特性,开发提取此类信息的分析方法挑战巨大。本文研究了一些现有的分析算法,特别是深度学习算法,作为处理大数据的工具,还解释了... 详细信息

本文介绍了“大数据”,特别是智能电网中的大数据。大量数据(大数据)包含大量信息,然而,由于大数据的一些特性,开发提取此类信息的分析方法挑战巨大。本文研究了一些现有的分析算法,特别是深度学习算法,作为处理大数据的工具,还解释了深度学习在智能电网中应用的潜力。

关键词：智能电网大数据深度学习应用潜力

内镜下逆行胰胆管造影治疗儿童胆总管结石并发急性胰腺炎一例(附内镜下视频)

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中国小儿急救医学 2024年第2期31卷 93-97页

作者：王跃生李子颖李小芹郑州大学附属儿童医院消化内科 450018

目的探讨内镜下逆行胰胆管造影(ERCP)在儿童胆总管结石并发急性胰腺炎中的应用价值。方法回顾性分析郑州大学附属儿童医院收治的1例胆总管结石并发急性胰腺炎患儿的诊断与治疗经过,分析ERCP在儿童胆管结石诊治中的作用。结果患儿,男,13... 详细信息

目的探讨内镜下逆行胰胆管造影(ERCP)在儿童胆总管结石并发急性胰腺炎中的应用价值。方法回顾性分析郑州大学附属儿童医院收治的1例胆总管结石并发急性胰腺炎患儿的诊断与治疗经过,分析ERCP在儿童胆管结石诊治中的作用。结果患儿,男,13岁11个月,因间断腹痛、呕吐1个月,加重2 h就诊,确诊为胆总管结石并发急性腹腺炎接受ERCP治疗。球囊扩张十二指肠乳头扩约肌,应用取石网篮取石,取出胆总管结石及大量泥沙样结石。术后置入鼻胆引流管一根,于术后1周改为内支架引流,患儿病情好转。结论ERCP治疗儿童胆总管结石并发急性胰腺炎可快速缓解临床症状,改善实验室检查指标。

关键词：内镜下逆行胰胆管造影术胆总管结石胰腺炎儿童

Reliability-Based Topology Optimization of Fail-Safe Structures Using Moving Morphable Bars

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 3173-3195页

作者： Xuan wang Yuankun Shi Van-Nam Hoang Zeng Meng Kai Long yuesheng wang School of Mechanical Engineering Tianjin UniversityTianjin300072China Department of Engineering Mechanics Hefei University of TechnologyHefei230009China Mechanical Engineering Institute Vietnam Maritime UniversityHai Phong City180000Vietnam State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing102206China

This paper proposes an effective reliability design optimizationmethod for fail-safe topology optimization(FSTO)considering uncertainty based on the moving morphable bars method to establish the ideal balance between cost and robustness,reliability and structural *** this end,a performancemeasure approach(PMA)-based doubleloop optimization algorithmis developed tominimize the relative volume percentage while achieving the reliability *** ensure the compliance value of the worst failure case can better approximate the quantified design requirement,a p-norm constraint approach with correction parameter is ***,the significance of accounting for uncertainty in the fail-safe design is illustrated by contrasting the findings of the proposed reliabilitybased topology optimization(RBTO)method with those of the deterministic design method in three typical *** Carlo simulation shows that the relative error of the reliability index of the optimized structure does not exceed 3%.

关键词： Topology optimization fail-safe design uncertainty reliability-based topology optimization moving morphable bars