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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 213-221页

作者： chunyi Guo Peng cui Chengyong Zhao School of Electrical Engineering North China Electric Power UniversityBeijing 102206China

This paper investigates the small-signal stability of the hybrid high-voltage direct current(HVDC)transmission *** system is composed of line commutated converter(LCC)as rectifier and modular multi-level converter(MMC)as inverter under weak AC grid ***,the impact of short-circuit ratio(SCR)at inverter side on the system stability is investigated by eigen-analysis,and the key control parameters which have major impact on the dominant mode are identified by the participation factor and sensitivity ***,considering the quadratic index and damping ratio characteristic,an objective function for evaluating the system stability is developed,and an optimization and configuration method for control parameters is presented by the utilization of Monte Carlo *** eigenvalue results and the electromagnetic transient(EMT)simulation results show that,with the optimized control parameters,the small-signal stability and the dynamic responses of the hybrid system are greatly improved,and the hybrid system can even operate under weak AC grid condition.

关键词： Hybrid high-voltage direct current(HVDC) line commutated converter(LCC) modular multi-level converter(MMC) optimization of control parameter

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非饱和土的一种分类方法

岩土工程技术 2007年第3期21卷 134-138页

作者：李顺群崔春义郑刚天津大学建筑工程学院大连理工大学土木水利学院辽宁大连116024

根据理想模型中土颗粒和孔隙水之间的几何关系、热力学原理和土力学基本理论,研究了土的非饱和性在非饱和土中引起的力系。给出了张力吸力和吸力比的定义,并在考虑基质吸力作用面积的基础上定义了等效吸力的概念。按照孔隙水弯液面是否... 详细信息

根据理想模型中土颗粒和孔隙水之间的几何关系、热力学原理和土力学基本理论,研究了土的非饱和性在非饱和土中引起的力系。给出了张力吸力和吸力比的定义,并在考虑基质吸力作用面积的基础上定义了等效吸力的概念。按照孔隙水弯液面是否与土颗粒表面搭接,将非饱和土分为搭接非饱和土和不搭接非饱和土两类。进而根据搭接状态将搭接非饱和土细分为水封闭非饱和土和搭接双开敞非饱和土,根据孔隙气状态将不搭接非饱和土细分为不搭接双开敞非饱和土和气封闭非饱和土。在搭接非饱和土中,出现张力吸力并对土体的强度产生增强作用;在不搭接非饱和土中,表面张力只是沿着液面传播,不对土的强度产生效应。另外,张力吸力只对强度问题有贡献,它不是渗流问题的驱动力。

关键词：非饱和土张力吸力合吸力吸力比等效吸力

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基于知识图谱和熵值优化的高桩码头模糊评估

水利水运工程学报 2024年第5期 72-83页

作者：张鹏周一恒崔春义季则舟周扬刘志新大连海事大学交通运输工程学院辽宁大连116026 中交第一航务工程勘察设计院有限公司天津300222 大连理工大学水利工程学院辽宁大连116024 中国建筑一局(集团)有限公司北京100161

高桩码头应用广泛,在其服役期内可能受到超载、淤积、环境腐蚀等因素影响,出现结构性能退化,对其进行服役性态评估具有重要价值。基于已有行业规范与工程案例整理了中国常见码头结构形式的服役性态评估指标体系,采用Top-down方式创建指... 详细信息

高桩码头应用广泛,在其服役期内可能受到超载、淤积、环境腐蚀等因素影响,出现结构性能退化,对其进行服役性态评估具有重要价值。基于已有行业规范与工程案例整理了中国常见码头结构形式的服役性态评估指标体系,采用Top-down方式创建指标体系的知识图谱,并利用visNetwork工具包编写指标体系内核代码与BS架构交互界面。结合AHP-FCE法与评估指标进行码头服役性态评估:建立评语集与评估等级集进而得到模糊评估向量;采用熵值法(EM)对层次分析(AHP)中的权值进行修正,从而实现客观赋权。最后,以中国东南沿海某海港高桩码头结构为例进行流程演示,结合该工程特点从知识图谱中抽取安全评估指标并建立该工程分级评估系统,分层计算模糊评估向量并得到码头整体安全等级为A级。该结果与工程检测机构评估结果一致,验证了所建知识图谱的适用性与修正的AHP-FCE法的正确性,说明该方法可推广应用于其他各类码头结构的运维评估。

关键词：指标体系知识图谱层次分析法熵值法模糊综合评估服役性态

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考虑清淤策略的桩基时变可靠度分析

水利水运工程学报 2024年第5期 22-30页

作者：韩清宇崔春义熊琦赵敏刘海龙尤再进季则舟大连海事大学交通运输工程学院辽宁大连116026 大连海事大学港口与航运安全协同创新中心辽宁大连116026 中交第三航务工程勘察设计院有限公司上海200032 中交第一航务工程勘察设计院有限公司天津300222

为发展淤积岸坡-高桩码头相互作用体系结构可靠性分析方法,基于Fick第二定律推导了能考虑氯离子侵蚀效应的二维扩散模型,并采用时间离散法提出了一种综合考虑结构抗力衰减、淤积作用量化和预测,以及桩基受力变形分析的高桩码头桩基时变... 详细信息

为发展淤积岸坡-高桩码头相互作用体系结构可靠性分析方法,基于Fick第二定律推导了能考虑氯离子侵蚀效应的二维扩散模型,并采用时间离散法提出了一种综合考虑结构抗力衰减、淤积作用量化和预测,以及桩基受力变形分析的高桩码头桩基时变可靠度数值计算方法。并结合以目标可靠度为导向的清淤策略,编写了淤积岸坡-高桩码头体系时变可靠度外挂求解程序DPRP。在此基础上,开展了多工况计算分析,探讨了高桩码头桩基时变可靠度的演化规律。计算分析结果表明:码头近海侧桩基可靠度更易低于目标可靠度,在实际工程中需重点养护与修复;泥沙淤积作用会降低多数桩基时变可靠度,而对于近海侧及近岸侧且向岸倾斜的斜桩,其时变可靠度则会因泥沙淤积作用而增大。该高桩码头桩基时变可靠度数值求解流程框架及对应外挂子程序DPRP,可为高桩码头-岸坡相互作用体系的相关工程设计与可靠性评价提供参考。

关键词：高桩码头淤积氯离子侵蚀时间离散法可靠性分析清淤策略

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饱和软土场地格栅加筋路堤地震动力响应分析

信阳师范学院学报（自然科学版） 2019年第1期32卷 163-167页

作者：张利伟梁志孟朱江山孟坤崔春义李顺群新乡学院土木工程与建筑学院河南新乡453000 大连海事大学土木工程系辽宁大连116026 天津城市建设学院土木工程系天津300384

为探讨饱和软土场地中格栅加筋路堤地震动力响应特性规律,基于大型通用有限元分析软件ADINA,建立了饱和软土地基上格栅加筋路堤的数值分析模型,研究了布筋方式、筋材弹性模量与间距及路堤填料性质对格栅加筋路堤地震动力响应的影响规律... 详细信息

为探讨饱和软土场地中格栅加筋路堤地震动力响应特性规律,基于大型通用有限元分析软件ADINA,建立了饱和软土地基上格栅加筋路堤的数值分析模型,研究了布筋方式、筋材弹性模量与间距及路堤填料性质对格栅加筋路堤地震动力响应的影响规律.结果表明:增大筋材弹性模量可有效提升路堤动力稳定性,且筋材越靠近路堤底部其效果越显著;随着加筋层数增加,加筋效果提升率有所衰减;增加填料摩擦角和填料黏聚力可提高加筋路堤动力性能,但填料土性参数达到一定幅值后,其变化所引起动力性能提升效果降低.

关键词：土工格柵加筋路堤饱和软土场地地震动力响应数值分析参数分析

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海上风机结构健康监测实践教学平台建设

中国现代教育装备 2024年第13期 47-50页

作者：张鹏何征结崔春义任亮姚茹青大连海事大学交通运输工程学院辽宁大连116026 大连理工大学建设工程学部辽宁大连116023 大连海事大学国际联合学院辽宁大连116026

为加深学生对结构健康监测理论、实验测试方法等的理解,提高实践技能,以海上风机结构及大直径管桩为背景建立了实践教学平台,实现了对风机正常运转、叶片损伤、螺栓松动、基础泥面变化等多种工况的模拟。基于UDP通信协议编写了开源硬件... 详细信息

为加深学生对结构健康监测理论、实验测试方法等的理解,提高实践技能,以海上风机结构及大直径管桩为背景建立了实践教学平台,实现了对风机正常运转、叶片损伤、螺栓松动、基础泥面变化等多种工况的模拟。基于UDP通信协议编写了开源硬件平台的数据采集测试系统,综合使用随机子空间及随机减量法得到风机结构模态信息。学生可基于此平台掌握结构健康监测、模态分析、损伤识别、振动测试的相关知识和实践技能。

关键词：海上风机健康监测模态识别结构损伤

Organic materials-based cathode for zinc ion battery

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SmartMat 2022年第4期3卷 565-581页

作者： Huilin cui Longtao Ma Zhaodong Huang Ze Chen chunyi Zhi Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Frontiers Science Center for Flexible Electronics Institute of Flexible ElectronicsNorthwestern Polytechnical UniversityXi'anChina Hong Kong Center for Cerebro-Cardiovascular Health Engineering(COCHE) ShatinNTHong KongChina Hong Kong Institute for Clean Energy City University of Hong KongKowloonHong KongChina

The quest for advanced energy storage devices with cheaper,safer,more resource-abundant storage has triggered intense research into zinc ion batteries(ZIBs).Among them,organic materials as cathode materials for ZIBs have attracted great interest due to their flexible structure designability,high theoretical capacity,environmental friendliness,and *** numerous organic electrode materials have been studied and different redox mechanisms have been proposed in the past decade,their electrochemical performance still needs further improvement,and the mechanisms require further *** paper provides a systematical overview of three types of organic materials(bipolar-type conductive polymer,n-type conjugated carbonyl compounds,and p-type material)on the energy storage mechanisms and distinct *** then focus on discussing the design strategies to improve electrochemical ***,the challenges and future research directions are discussed to provide a foundation for further developing organic-based ZIBs.

关键词： aqueous electrolyte batteries organic cathode materials zinc ion batteries

Carrier diffusion coefficient is independent of defects in CH_(3)NH_(3)PbBr_(3) single crystals:Direct evidence

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Journal of Energy Chemistry 2021年第7期30卷 441-445页

作者： chunyi Zhao Qi Sun Rongrong cui Jing Leng Wenming Tian Shengye Jin State Key Laboratory of Molecular Reaction Dynamics and the Dynamic Research Center for Energy and Environmental Materials Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina University of Chinese Academy of Sciences Beijing 100049China

Organolead halide perovskite solar cells have attracted extensive interests in recent years. Thanks to innovations in materials process and technology, the power conversion efficiency (PCE) of perovskites-based solar cells increases from 3.8% to 25.2%[1–4].In evaluating the quality of perovskite materials, a few key photophysical properties such as the lifetime, mobility and diffusion length of photogenerated carriers are usually measured.

关键词： Perovskite Defects Charge mobility Carrier lifetime Diffusion length

Recent Advances in Aqueous Zn||MnO_(2)Batteries

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Transactions of Tianjin University 2024年第1期30卷 27-39页

作者： Chuan Li Rong Zhang Huilin cui Yanbo Wang Guojin Liang chunyi Zhi Department of Materials Science and Engineering City University of Hong Kong83 Tat Chee AvenueKowloon 999077Hong KongChina Faculty of Materials Science and Energy Engineering/Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Hong Kong Institute for Clean Energy City University of Hong KongKowloon 999077Hong KongChina Hong Kong Institute for Advanced Study City University of Hong KongKowloon 999077Hong KongChina

Recently,rechargeable aqueous zinc-based batteries using manganese oxide as the cathode(e.g.,MnO_(2))have gained attention due to their inherent safety,environmental friendliness,and low *** their potential,achieving high energy density in Zn||MnO_(2)batteries remains challenging,highlighting the need to understand the electrochemical reaction mechanisms underlying these batteries more deeply and optimize battery components,including electrodes and *** review comprehensively summarizes the latest advancements for understanding the electrochemistry reaction mechanisms and designing electrodes and electrolytes for Zn||MnO_(2)batteries in mildly and strongly acidic ***,we highlight the key challenges hindering the extensive application of Zn||MnO_(2)batteries,including high-voltage requirements and areal capacity,and propose innovative solutions to overcome these *** suggest that MnO_(2)/Mn^(2+)conversion in neutral electrolytes is a crucial aspect that needs to be addressed to achieve high-performance Zn||MnO_(2)*** approaches could lead to breakthroughs in the future development of Zn||MnO_(2)batteries,off ering a more sustainable,costeff ective,and high-performance alternative to traditional batteries.

关键词： Aqueous Zn||MnO_(2)batteries Zinc-ion batteries Zinc batteries MnO_(2)

Sn-decorated CeO_(2) with different morphologies for direct dehydrogenation of ethylbenzene

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Journal of Rare Earths 2024年第1期42卷 102-109,I0004页

作者： Kai Zhang Guoju cui Mengzhen Yuan Huiwen Huang Ning Li Jiale Xu Guowei Wang chunyi Li State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao266580China Petrochemical Plant of Sinopec Shengli Oilfield Company Dongying257237China College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao266590China

Three Sn-decorated ceria catalysts with various morphologies(rods,particles,and cubes)were prepared and applied to the direct dehydrogenation of ***-technology characterizations,including X-ray photoelectro n spectroscopy(XPS),H_(2)-tempe rature programmed reduction(H_(2)-TPR),and Raman spectroscopy,prove that the oxygen vacancies are the active sites for ethylbenzene dehydrogenation,which can be regulated by engineering CeO_(2) morphology and enhanced via introducing metal *** the results of activity test,the catalytic activities for ethylbenzene dehydrogenation over different samples are closely dependent on the amount of oxygen *** reduced Sn-decorated CeO_(2) catalyst with nanoparticles morphology exhibits better dehydrogenation performance than the other two studied catalysts at 600℃.This work provides an effective approach to regulate the active oxygen vacancies and further enhance the dehydrogenation activities through engineering the surface morphology of the catalyst and introducing suitable additives.

关键词： Ethylbenzene dehydrogenation CeO_(2) Sn Morphology Oxygen vacancy Rare earths