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级联H桥型光伏逆变器的功率匹配控制策略

电力电子技术 2024年第6期58卷 85-87,105页

作者：林珊赵涛杜磊广州地铁设计研究院股份有限公司广东广州510010 青岛大学山东青岛266071 合肥工业大学安徽合肥230002

功率不匹配是单相级联H桥(CHB)光伏并网逆变器固有的问题,导致传输功率较大的H桥单元过调制、并网电流严重畸变甚至振荡过流。为此,这里提出一种基于特定次谐波补偿的级联型光伏逆变器功率匹配控制策略,通过给过调制的H桥单元注入最优的... 详细信息

功率不匹配是单相级联H桥(CHB)光伏并网逆变器固有的问题,导致传输功率较大的H桥单元过调制、并网电流严重畸变甚至振荡过流。为此,这里提出一种基于特定次谐波补偿的级联型光伏逆变器功率匹配控制策略,通过给过调制的H桥单元注入最优的3,5,7,9次谐波使其线性调制范围从1扩大至1.2438,同时采用闭环控制方法给非过调制H桥补偿反向谐波,能够确保逆变器在输入功率差异较大的条件下稳定运行且并网电流的总谐波畸变率(THD)较小。最后,实验结果验证了所提控制策略的可行性和有效性。

关键词：光伏逆变器功率匹配特定次谐波补偿

检察侦查和刑事执行检察研究回顾与展望--2023年检察侦查和刑事执行检察研究综述

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人民检察 2024年第2期 24-28页

作者：侯亚辉杜磊最高人民检察院第五检察厅中国人民大学刑事法律科学暨刑事执行检察研究中心

2023年,全国检察机关以“高质效办好每一个案件”为目标,推动检察侦查和刑事执行检察高质量发展,取得了显著成效。学界和实务界高度关注这项工作,产出了一批高水平研究成果,繁荣了检察侦查和刑事执行检察理论研究,为推进检察工作现代化... 详细信息

2023年,全国检察机关以“高质效办好每一个案件”为目标,推动检察侦查和刑事执行检察高质量发展,取得了显著成效。学界和实务界高度关注这项工作,产出了一批高水平研究成果,繁荣了检察侦查和刑事执行检察理论研究,为推进检察工作现代化贡献了宝贵的智慧。一、检察侦查权理论研究取得长足进步(一)对检察侦查权的属性定位日渐清晰检察侦查在“四大检察”体系中并无系统性安排,如何认识检察侦查权的定位是学界和实务界关注的一大课题。

关键词：刑事执行检察检察侦查权检察工作检察机关属性定位显著成效研究回顾与展望研究综述

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不同气囊压力气垫船空投入水研究

舰船科学技术 2024年第5期46卷 34-38页

作者：陈海斌张龙杜雷雨洪亮泰州市金海运船用设备有限责任公司江苏泰州225324 南京理工大学能源与动力工程学院江苏南京210094

为保证气垫船在特殊情况的应用,对气垫船空投入水进行研究。应用Abaqus有限元分析软件对气垫船气囊建立空气弹簧模型,对气囊不同气压时气垫船入水过程的运动特性和姿态变化进行仿真分析。结果表明:气囊的运动因空气弹簧存在的原因较底... 详细信息

为保证气垫船在特殊情况的应用,对气垫船空投入水进行研究。应用Abaqus有限元分析软件对气垫船气囊建立空气弹簧模型,对气囊不同气压时气垫船入水过程的运动特性和姿态变化进行仿真分析。结果表明:气囊的运动因空气弹簧存在的原因较底板更为剧烈;气囊气压在0.2~0.3 MPa间的运动特性几乎一致,小于0.2 MPa时气囊的弹性势能较小,速度衰减较慢,入水后吃水更深;气囊气压在0.15~0.3 MPa内,气垫船入水的姿态由前倾变为后倾,气压为0.2 MPa时,气垫船入水全程的姿态变化不大。总的来说,气垫船气囊压力为0.2 MPa时入水运动特性较好,姿态始末变化不大。

关键词：气垫船空投入水流体腔运动特性运动姿态

On the Effects of Risk Pooling in Supply Chain Management:Review and Extensions

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Acta Mathematicae Applicatae Sinica 2009年第4期25卷 709-722页

作者： Xia Cai Dong-lei du Faculty of Business Administration University of New Brunswick P.O. Box 4400 Fredericton NB Canada E3B 5A3

The primary challenge in supply chain management （SCM） is matching supply with uncertain demand. Risk pooling is an efficient and promising strategy to meet this challenge by reducing the underlying demand uncertainty through aggregation. The main focus of this paper is to analyze the effects of risk pooling under different supply chain settings. There are two main contributions. First, we propose a mathematical framework which serves the multi-purpose of （1） unifying existing models on risk pooling in the literature, （2） providing new facets and insights of understanding existing results on risk pooling, and （3） setting up new ground for extending existing models and results. Second; we investigate one interesting effect of risk pooling, namely, the decreasing marginal return （or supermodularity）. We show that there are decreasing marginal returns in risk pooling practices under certain conditions, specifically when the demand is independent and identically distributed （I.I.D.） and normally distributed.

关键词： Lead Time Supply Chain Management Distribution Center Order Quantity Retail Store

A giant atom with modulated transition frequency

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Frontiers of physics 2023年第1期18卷 209-218页

作者： lei du Yan Zhang Yong Li Center for Theoretical Physics and School of Science Hainan UniversityHaikou 570228China Beijing Computational Science Research Center Beijing 100193China Center for Quantum Sciences and School of Physics Northeast Normal UniversityChangchun 130024China Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal UniversityChangsha 410081China

Giant atoms are known for the frequency-dependent spontaneous emission and associated interference *** this paper,we study the spontaneous emission dynamics of a two-level giant atom with dynamically modulated transition *** is shown that the retarded feedback effect of the giant-atom system is greatly modified by a dynamical phase arising from the frequency modulation and the retardation effect ***,such a modification can in turn suppress the retarded feedback such that the giant atom behaves like a small *** introducing an additional phase difference between the two atom-waveguide coupling paths,we also demonstrate the possibility of realizing chiral and tunable temporal profiles of the output *** results in this paper have potential applications in quantum information processing and quantum network engineering.

关键词： giant atoms frequency modulation spontaneous emission dynamics non-Markovian retardation effect

Spatial Interaction Between the Industrial Undertaking Capacity and Global Value Chain Position of East Asian Countries

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Chinese Geographical Science 2021年第1期31卷 81-92页

作者： ZHU Binbin CHI Fangyuan du lei School of Economics and Management Northeast Normal UniversityChangchun 130117China Jilin Academy of Social Sciences Changchun 130033China

A comprehensive understanding of the spatial interaction between the industrial undertaking capability and the position of the global value chain of the 12 East Asian countries is conducive to strengthening regional cooperation, gaining a say in foreign trade and becoming the dominant player in the global division of labor system. The article reveals the operating rules of the interaction between the industrial undertaking capacity and the global value chain position of East Asian countries by calculating the Global Moran Index(Moran’s I), coupling coordination degree and other indicators. The results show that: in time, the values of industrial undertaking capacity and the positions of global value chain in East Asian countries showed a sustained and stable growth trend, and have a consistent trend of change. Spatially, both of the two indexes had significant positive spatial correlation, with Moran’s I showing an ‘inverted U’pattern, and the spatial aggregation distribution of global value chain position lagged behind the spatial aggregation distribution of industrial undertaking capacity by one year. In terms of spatial coupling coordination, the coupling coordination values of the two indicators show a steady upward trend. Combined with the comparative advantage of each country, this paper provides suggestions for promoting the positions of Chinese and other East Asian industries in the global value chain from the perspectives of enhancing independent innovation capability and upgrading industrial structure.

关键词： 12 countries East Asian countries industry undertaking capability global value chain position spatial interaction

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电子通讯产品国际竞争格局研究

湖南财政经济学院学报 2024年第2期40卷 74-84页

作者：陈友余余宙杜磊湖南财政经济学院会计学院湖南长沙410205 长沙理工大学经济与管理学院湖南长沙410076 吉林省社会科学院吉林长春130033

基于60个经济体2011-2022年的电子通讯产品双边贸易数据,运用社会网络分析方法,构建电子通讯产品国际竞争网络。研究发现:电子通讯产品竞争网络“抱团”现象显著,中国扮演了中心国角色,是最重要的“桥梁”和“中介”;网络内凝聚子群类... 详细信息

基于60个经济体2011-2022年的电子通讯产品双边贸易数据,运用社会网络分析方法,构建电子通讯产品国际竞争网络。研究发现:电子通讯产品竞争网络“抱团”现象显著,中国扮演了中心国角色,是最重要的“桥梁”和“中介”;网络内凝聚子群类型可分为内大外弱社团、内小外弱社团和内大外强社团等三类,中国一直稳居贸易核心区域,位列“内大外强”社团,在动态竞争变迁过程中具有良好的“马太效应”,但可能丧失“规模效应”,使内外发展动能受限;中美贸易摩擦助推部分经济体控制力两极分化,可能危及产业独立性,导致贸易伙伴选择上出现“舍近求远”现象。

关键词：电子通讯产品社会网络社团分布 “卡脖子”风险

维普期刊数据库博看期刊

Oxidation of benzyl alcohols to ketones and aldehydes by O3 process enhanced using high-gravity technology

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Chinese Journal of Chemical Engineering 2020年第3期28卷 808-814页

作者： Wenqiang Gao lei du Weizhou Jiao Youzhi Liu Shanxi Province Key Laboratory of Higee-Oriented Chemical Engineering North University of ChinaTaiyuan 030051China Department of Chemistry and Chemical Engineering Luliang UniversityLuliang033000China

In this study,a practical process for ozonization of benzyl alcohols to ketones and aldehydes in a rotating packed bed(RPB-O3)reactor has been *** 1-phenylethanol as a model reactant,the performance of RPB-O3 process in different solvents has been compared with the commonly used stirred tank reactor(STR-O3).Ethyl acetate was the optimum solvent for the conversion of 1-phenylenthanol to acetophenone in RPB-O3 process,with 78%yield after 30 *** a parallel STR-O3 experiment,the yield of acetophenone was50%.Other experimental variables,i.e.O3 concentration,reaction time,high-gravity factor and liquid flow rate were also *** highest yield of acetophenone was obtained using O3 concentration of 80 mg·L-1,reaction time of 30 min,high gravity factor of 40 and liquid flow rate of 120 L·*** the optimized reaction conditions,a series of structurally diverse primary and secondary alcohols was oxidized with(19%–92%)*** ozonization mechanism was studied by Electron Paramagnetic Resonance(EPR)spectroscopy,monitoring the radical species formed upon self-decomposition of *** characteristic quadruple peak with the 1:2:2:1 intensity ratio that corresponds to hydroxyl radicals(·OH)was observed in the electron paramagnetic resonance(EPR)spectrum,indicating an indirect oxidation mechanism of alcohols via·OH radical.

关键词： Ozone Benzyl alcohols Aldehydes and ketones High-gravity technology

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成煤环境约束下的煤分子结构差异特征

石化技术 2024年第8期31卷 95-97页

作者：杜磊郭庆高立凯陕西省煤田物探测绘有限公司陕西西安710005

认识不同成煤地质背景的煤分子结构是煤炭清洁高效转化的基础,分别选择两种不同煤相特征的样品进行分子结构对比,结果表明:具有更高凝胶化程度、更少木质组织的N22样品芳环取代结构类型更为多样且数量均匀,脂肪结构也更为丰富,尤以边基... 详细信息

认识不同成煤地质背景的煤分子结构是煤炭清洁高效转化的基础,分别选择两种不同煤相特征的样品进行分子结构对比,结果表明:具有更高凝胶化程度、更少木质组织的N22样品芳环取代结构类型更为多样且数量均匀,脂肪结构也更为丰富,尤以边基侧链结构最为显著。相反的,Z52样品的芳环五取代结构明显多于其它取代结构,含氧结构和脂肪结构的类型也相对较少。

关键词：煤环境煤相分子结构