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Performance Evaluation of Two-Vector-Based Model Predictive Current Control of PMSM Drives

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Chinese Journal of Electrical Engineering 2018年第2期4卷 65-81页

作者： Yongchang Zhang Lanlan Huang donglin xu Jiali Liu Jialin Jin Inverter Technologies Engineering Research Center of Beijing North China University of TechnologyBeijing 100144China

Conventional model predictive current control(MPCC)applies only one vector during one control period,which produces large torque and flux ripples and high current harmonics in permanent magnet synchronous motor(PMSM)*** MPCC with duty cycle control has been proposed to improve the steady state performance by applying one non-zero vector and one null vector during one control ***,the prior method requires lots of calculations and predictions to find the optimal voltage vectors and calculate their respective *** from prior enumeration-based MPCC,this paper proposes an efficient two-vector MPCC by applying two arbitrary voltage vectors during one control *** reference voltage vector is firstly calculated based on the principle of deadbeat current *** optimal vectors and their duration are then obtained in a very efficient way,which does not require the calculation of current slopes in prior MPCC *** proposed method is compared to the state-of-the-art predictive control methods,including conventional MPCC,MPCC with duty cycle control,deadbeat control with space vector modulation(SVM)and modulated model predictive control(M2PC).Both simulation and experimental results prove that the proposed method achieves better steady state performance than conventional MPCC with or without duty cycle and the dynamic response is not *** the condition of insufficient dc bus voltage,the proposed method outperforms deadbeat control and M2PC by presenting even higher speed range and less torque ripples.

关键词： Predictive control current control PMSM drives

Southern rice black-streaked dwarf virus:A new proposed Fijivirus species in the family Reoviridae

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Chinese Science Bulletin 2008年第23期53卷 3677-3685页

作者： ZHOU GuoHui WEN JingJung CAI DeJiang LI Peng xu donglin ZHANG ShuGuang Laboratory of Plant Virology South China Agricultural University Guangzhou 510642 China Plant Protection Station Agricultural Department of Hainan Province H-aikou 570003 China

For the past several years, a novel dwarf disease has been observed on rice (Oryza sativa) in some regions of Guangdong Province and Hainan Province, southern China. Infected plants showed stunting, dark leaf and small enations on stem and leaf back. Typical Fijivirus viroplasma containing crystalline arrayed spherical virons approximately 70―75 nm in diameter and tubular structures were detected in ultrathin sections by an electron microscope in parenchyma phloem cells of the infected plants. The virus was transmitted to rice seedlings by white-backed planthoppers, Sogatella furcifera (Hemiptera: Delphacidae), collected in the diseased fields. Analysis of dsRNA extracts from infected plants revealed ten linear segments, which were similar to the electrophoretic profile of Rice black-streaked dwarf virus (RBSDV). RT-PCR with a single primer which matched to a linker sequence ligated to both 3′ ends of the viral genomic dsRNAs resulted in amplification of genome segments 9 (S9) and 10 (S10) cDNA products. The complete nucleotide sequences of S9 and S10 were obtained from clones of the RT-PCR amplicon exhibited characteristic properties of Fijivirus including low GC content (34.5% and 35.6%), genus conserved 5′ and 3′ termini sequences and similar genome organization. Blast searches indicated that the sequences of S9 and S10 shared 68.8%―74.9% and 67.1%―77.4% nucleotide identities with those of viruses in the Fijivirus group 2, respectively. These values were similar to those among other viruses in the Fijivirus group 2 and considerably lower than those among RBSDV isolates. Phylogenetic trees based on S9 and S10 nucleotide sequences and their putative amino acid sequences showed that this virus represented a separate branch among other Fijiviruses. The virus was also detected by a nested RT-PCR assay in corn (Zea mays), barnyard grass (Echinochloa crusgalli), Juncellus serotinus and flaccidgrass (Pennisetum flaccidum) in and/or adjacent to the infected rice fields. I

关键词：水稻矮化病基因组染色体预防措施

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基于XMPP网络的嘟一下的设计与实现

数字通信世界 2024年第2期 78-80页

作者：费相如戴胜林许东林胡谢斐中国电信股份有限公司安徽分公司安徽合肥230001

文章通过分析XMPP核心协议和企业级IMS(EIMS)的需求,通过开发Openfire服务器和集成自定义数据库为EIMS设计了一个实施框架。我们所提供的基于XMPP的解决方案——嘟一下,具备更好的安全性和开放性,并且支持跨平台应用,可以用最小的成本... 详细信息

文章通过分析XMPP核心协议和企业级IMS(EIMS)的需求,通过开发Openfire服务器和集成自定义数据库为EIMS设计了一个实施框架。我们所提供的基于XMPP的解决方案——嘟一下,具备更好的安全性和开放性,并且支持跨平台应用,可以用最小的成本将基于网络的IMS整合到公司内部应用和服务当中。

关键词：即时通信系统(IMS) XMPP 嘟一下用户数据库集成 Openfire

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紫菜薹线粒体基因组SSR分布特征的比较分析

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福建农业学报 2024年第1期39卷 49-56页

作者：肖婉钰周贤玉任海龙黄红弟郑岩松张晶许东林广州市农业科学研究院广东广州510308 广东省农业科学院作物研究所/广东省农作物遗传改良重点实验室广东广州510640 广东省良种引进服务公司广东广州510091

【目的】分析紫菜薹(Brassica rapa ***)线粒体基因组SSR序列的分布特征,并与芸薹属主要物种进行比较,为紫菜薹SSR分子标记的开发及遗传进化研究提供参考。【方法】利用MISA软件对紫菜薹及芸薹属6个基本种(包括白菜3个变种)的线粒体基... 详细信息

【目的】分析紫菜薹(Brassica rapa ***)线粒体基因组SSR序列的分布特征,并与芸薹属主要物种进行比较,为紫菜薹SSR分子标记的开发及遗传进化研究提供参考。【方法】利用MISA软件对紫菜薹及芸薹属6个基本种(包括白菜3个变种)的线粒体基因组进行搜索,并对搜索到的SSR序列分布特征进行比较分析。【结果】在紫菜薹及芸薹属6个基本种(包括白菜3个变种)的线粒体基因组中,分别筛选到168、170、167、168、180、280、185、165、179个完整的SSR序列,相对密度分别为764、774、760、764、775、777、721、744、771个·Mb-1,SSR序列的总长度分别为1562、1577、1547、1562、1664、2564、1722、1524、1646 bp,占各自线粒体基因组序列总长度的比例分别为0.71%、0.72%、0.70%、0.71%、0.72%、0.71%、0.67%、0.69%和0.71%。在1~6个不同核苷酸重复单元中,紫菜薹及芸薹属6个基本种的SSR序列均是单核苷酸重复单元最多,然后依次是二核苷酸、四核苷酸、三核苷酸、五核苷酸,均未发现六核苷酸重复单元。其中,A/T、AG/CT、AT/AT和C/G是芸薹属线粒体基因组共有的常见重复单元类型。【结论】紫菜薹线粒体基因组大小为219779 bp,共筛选出168个SSR分子标记,相对密度为764个·Mb-1,平均长度为9 bp,以单核苷酸重复单元的数量最多,其次为二、四核苷酸重复单元类型,具有较大的多态性标记开发潜力。

关键词：紫菜薹芸薹属线粒体 SSR

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鞍山地区微细粒贫磁铁矿石磁选工艺研究

金属矿山 2024年第3期 94-98页

作者：李万兴吴俊杰宁辰禹徐冬林郑纪民郭小飞辽宁科技大学矿业工程学院辽宁鞍山114051 鞍钢集团矿业设计研究院有限公司辽宁鞍山114002 鞍钢集团鞍千矿业责任有限公司辽宁鞍山114043 威海市海王旋流器有限公司山东威海264204

鞍山地区许东沟和哑巴岭采区的铁矿石铁品位为29.50%,铁矿物主要为磁铁矿,主要脉石为石英。为高效开发利用该矿石,在采用X荧光分析、化学成分分析、铁物相检测和扫描电子显微镜分析矿石性质基础上,进行了湿式粗粒中磁预选—阶段磨矿、... 详细信息

鞍山地区许东沟和哑巴岭采区的铁矿石铁品位为29.50%,铁矿物主要为磁铁矿,主要脉石为石英。为高效开发利用该矿石,在采用X荧光分析、化学成分分析、铁物相检测和扫描电子显微镜分析矿石性质基础上,进行了湿式粗粒中磁预选—阶段磨矿、阶段弱磁选—淘洗机精选条件试验和扩大连选试验。结果表明:①-2.5 mm高压辊磨产品经过筒式磁选机中磁预选,粗精矿铁品位为40.20%、铁回收率为89.76%;②预选粗精矿经过两阶段磨矿(一、二段磨矿细度分别为-0.074 mm占75%和-0.045 mm占90%)、三阶段弱磁选和一段淘洗机精选,最终获得产率35.73%、铁品位67.08%、铁回收率81.24%的铁精矿,尾矿铁品位为8.61%,研究结果可作为该矿石开发利用依据。

关键词：贫磁铁矿微细粒粗粒预选阶段磨矿阶段磁选

OBSERVATION ON GENERATION Z'S SPRING FESTIVAL CONSUMPTION

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Good Neighbours 2022年第2期 32-37页

作者： xu donglin(Translated) 不详

With China's generation Z(people born between 1995 and 2009)gradually becoming the main force of consumption,the consumption ideas of the youngsters are deeply affecting the consumer market:semi-finished products are transformed into fancy New Year's Evedinner;traditional Chinese culture with tiger elements wins the heart of buyers;board roleplaying games(BRPG)and jubensha,or"script murder,"a role-playing murder mystery game,become popular entertainments.

关键词：春节消费变身消费市场文化强势年轻人

CHINESE SPRING FESTIVAL CELEBRATED AROUND THE GLOBE

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Good Neighbours 2022年第2期 22-25页

作者： xu donglin(Translated) 不详

Recently various forms of cultural activities have been held in many countries around the globe to celebrate the arrival of the Spring Festival of the Year of the Tiger in the Chinese lunar *** February 2,the Chinese Cultural Centerin Paris launched a special program called"literature and art of China"onits official website and online platform to offer wonderful cultural programs to Chinese nationals and students in France and extend New Year greetings to overseas Chinese all over the world.

关键词：文化中国活动春节庆祝

TRADITIONAL CHINESE FOOD OFFERED ON WINTER OLYMPIC MENU

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Good Neighbours 2022年第1期 52-53页

作者： xu donglin(Translated) 不详

The accommodation and catering preparations for the Beijing Winter Olympic Games are progressing in an orderly manner according to the press conference held in Shougang Park,Biing on December 10,*** the games,high-quality catering services with Chinese characteristics and warm,harmonious and convenient accommodation experience will be provided.

关键词：餐饮服务烤鸭春卷北京首钢元宵美食发布会有序推进

WHEN THE WINTER OLYMPIC GAMES COINCIDES WITH THE SPRING FESTIVAL

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Good Neighbours 2022年第2期 38-41页

作者： xu donglin(Translated) 不详

The Beijing Winter Olympic Games kicked off on February 4,coinciding with the joyous and festive Chinese Lunar New Year,or the Spring *** day is also"the Beginning of Spring",one of the 24 Chinese traditional solar te... 详细信息

关键词：木垒哈萨克自治县二十四节气赛里木湖迎新年洛浦县北京冬奥会冬奥