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异极式永磁偏置径向磁轴承的建模与实验 被引量:6
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作者 吴磊涛 王东 +2 位作者 苏振中 张贤彪 薛滟膑 《电工技术学报》 EI CSCD 北大核心 2018年第5期1051-1057,共7页
为了满足储能飞轮系统、卫星动量轮等对高空间利用率的需求,提出了一种异极式永磁偏置径向磁轴承的拓扑结构。通过在槽口放置平行充磁的永磁体获得紧凑的结构,同时永磁磁路和电励磁磁路耦合距离较短,有利于获取高解耦特性。该文首先采... 为了满足储能飞轮系统、卫星动量轮等对高空间利用率的需求,提出了一种异极式永磁偏置径向磁轴承的拓扑结构。通过在槽口放置平行充磁的永磁体获得紧凑的结构,同时永磁磁路和电励磁磁路耦合距离较短,有利于获取高解耦特性。该文首先采用磁力线法,分别获取考虑齿槽效应、转子偏心的永磁磁场、电励磁磁场的气隙磁通密度分布,建立了磁路模型;然后根据磁路模型求解位移刚度和电流刚度,建立磁轴承的数学模型;与有限元仿真进行对比,证明所建立的磁场模型能够准确计算气隙磁通密度分布。设计、制造一台实验样机并进行相关实验,实验结果验证了磁路模型及有限元仿真的可靠性。 展开更多
关键词 结构 磁路模型 有限元仿真 静态性能
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关于短跑的适宜步幅问题
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作者 常生 《体育与科学》 1983年第4期25-25,共1页
下表是据根国外著名学者詹森——弗希尔对短跑运动员最适宜步长计算公式所绘制的。(适宜步长=身高×1.17+110厘米)
关键词 适宜步长 优秀短跑运动员 计算公式 著名学者 据根 短跑成绩 放松能力 身体素质 运动技能 最佳成绩
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对黑龙江省经济发展战略的探讨
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作者 史寅生 《哈尔滨商业大学学报(社会科学版)》 1987年第3期12-16,共5页
黑龙江省资源丰富,能源工业和森林采伐有一定基础,农林牧副渔有广阔发展前途,粮、煤、木、油(石油)、机(机械工业)等主要产品在全国占重要地位,交通也比较发达,具有明显的经济开发优势。但是,由于生产单一,中央、地方条块分割,产业、产... 黑龙江省资源丰富,能源工业和森林采伐有一定基础,农林牧副渔有广阔发展前途,粮、煤、木、油(石油)、机(机械工业)等主要产品在全国占重要地位,交通也比较发达,具有明显的经济开发优势。但是,由于生产单一,中央、地方条块分割,产业、产品、技术结构不合理,消费和积累的比例不够合适等原因,使经济优势难以充分发挥,也影响了城乡人民物质文化生活的迅速提高。因此,对黑龙江经济的发展战略,有进一步探讨的必要。 展开更多
关键词 黑龙江经济 黑龙江省经济 地区经济发展战略 积累率 轻工业 粮食 经济开发优势 据根 农业经济区划 农轻重
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知识园
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作者 黄晓霞 《语文世界(上旬刊)》 2002年第11期8-8,共1页
关键词 知识园 成语 男孩子 四年级 会计 词语 评分 夏草 荷花 据根
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Generalized Dirichlet Normal Ordering in Open Bosonic Strings
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作者 CAO Zhen-Bin DUAN Yi-Shi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第1期110-114,共5页
Generally, open string boundary conditions play a nontrivial role in string theory. For example, in the presence of an antisymmetric tensor background field, they will lead the spacetime coordinates noncommutative. In... Generally, open string boundary conditions play a nontrivial role in string theory. For example, in the presence of an antisymmetric tensor background field, they will lead the spacetime coordinates noncommutative. In this paper, we mainly discuss how to build up a generalized Dirichlet normal ordered product of open bosonic string embedding operators that satisfies both the equations of motion and the generalized Dirichlet boundary conditions at the quantum level in the presence of an antisymmetric background field, as the generalized Neumann case has already been discussed in the literature. Further, we also give a brief check of the consistency of the theory under the newly introduced normal ordering. 展开更多
关键词 boundary conditions normal ordering
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A Review of the Nonlinear Dynamics of Intraseasonal Oscillations
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作者 ZHAO Qiang CHEN Jian-Zhou 《Atmospheric and Oceanic Science Letters》 2011年第5期253-256,共4页
In recent years,significant progress has been made regarding theories of intraseasonal oscillations (ISOs) (also known as the Madden-Julian oscillation (MJO) in the tropics).This short review introduces the latest adv... In recent years,significant progress has been made regarding theories of intraseasonal oscillations (ISOs) (also known as the Madden-Julian oscillation (MJO) in the tropics).This short review introduces the latest advances in ISO theories with an emphasis particularly on theoretical paradigms involving nonlinear dynamics in the following aspects:(1) the basic ideas and limitations of the previous and current theories and hypotheses regarding the MJO,(2) the new multi-scale theory of the MJO based on the intraseasonal planetary equatorial synoptic dynamics (IPESD) framework,and (3) nonlinear dynamics of ISOs in the extratropics based on the resonant triads of Rossby-Haurwitz waves. 展开更多
关键词 ISO MJO nonlinear dynamics
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Islamic Banking and Economic Growth: Evidence From Asia
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作者 Gholamreza Tajgardoon Mehdi Behname Khosro Noormohamadi 《Journal of Modern Accounting and Auditing》 2013年第4期542-546,共5页
This paper investigates the short- and long-run causality relationship between Islamic banking and the economic growth. The main goal of this paper is to examine the relationship between the economic growth and Islami... This paper investigates the short- and long-run causality relationship between Islamic banking and the economic growth. The main goal of this paper is to examine the relationship between the economic growth and Islamic banking. The dataset used covers the Asia countries over the period of 1980-2009. The unit root test Im, Pesaran, and Shin (IPS) (2003) confirms that all of the variables that the authors use in the equation below are stationary. The empirical result of the Granger causality test shows a bidirectional relationship between Islamic banking and the economic growth and also a bidirectional relationship between the economic growth and export. 展开更多
关键词 Islamic banking economic growth causality test Asia zone
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The weak form market efficiency investigation of American, European and Asian stock markets
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作者 Nuray Ergul 《Chinese Business Review》 2010年第10期1-11,共11页
This paper investigates the empirical validity of the Weak Form Efficient Market Hypothesis for American, European and Asian stock markets. Random Walk Hypothesis is used to prove weak form efficiency in American, Eur... This paper investigates the empirical validity of the Weak Form Efficient Market Hypothesis for American, European and Asian stock markets. Random Walk Hypothesis is used to prove weak form efficiency in American, European and Asian stock indices. ADF and PP Unit Root Tests have been used to test unit root in time series of daily data of American, European and Asian stock indices. Results show that sample of stock markets are weak-form efficient in terms of the Random Walk Hypothesis. 展开更多
关键词 weak form efficiency Random Walk Hypothesis unit root tests
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大数据视阈中的明清进士家族研究——以CBDB、中华寻根网为例 被引量:15
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作者 刘京臣 《北京大学学报(哲学社会科学版)》 CSSCI 北大核心 2019年第4期96-108,共13页
作为关系型数据库,"中国历代人物传记数据库M ( China Biographical Database Project,简称CBDB)因拥有42万多条中国历代人物传记数据而成为从大数据视角整体关照明清进士家族的首选。它的“亲属关系”査询,能够呈现亲属关系网络,... 作为关系型数据库,"中国历代人物传记数据库M ( China Biographical Database Project,简称CBDB)因拥有42万多条中国历代人物传记数据而成为从大数据视角整体关照明清进士家族的首选。它的“亲属关系”査询,能够呈现亲属关系网络,方便进行进士家族的梳理。同时,也应承认CBDB存在着匹配不准确、字段多重复等问题,这些问题可以借助家谱等文献得以解决。现阶段,中华寻根网提供了 2392种家谱影像全文,便于我们利用爬虫程序提取家谱目录中的相关信息,进而自动判断进士家族,这是对CBDB的有益补充。在此基础上,借助社会网络分析,可以直观呈现以血缘、姻亲为核心的进士家族世系图谱。姻亲关系能够将多个进士家族之间联系起来,可以使视角由单个进士家族向有关联的多个进士家族转移,例如可以考察这些姻亲家族在治经、传经等方面是否存在影响等。依赖家谱留存下来的家族成员的文学作品,既是考察家族文学发展流变的基础,又是建构更加广泛的社会网络分析图谱的基石。 展开更多
关键词 大数据 明清进士家族 CBDB 中华寻 家谱 社会网络分析
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基于智力城镇化的特色小镇产业培育探索——以辽宁通远堡镇为例 被引量:3
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作者 杨宁宁 高钰轩 +2 位作者 黄菖彬 邓兴浩 高雁鹏 《智能建筑与智慧城市》 2018年第9期88-91,94,共5页
我国城镇化正处于劣势的体力城镇化阶段,特色小镇作为新型城镇化的主力军,体力化威胁仍不可避免。为缓解特色小镇体力化困境,文章基于智力城镇化的相关理论,以辽宁通远堡镇为例,围绕特色产业展开智力化培育的探索。结合链式产业思维,以... 我国城镇化正处于劣势的体力城镇化阶段,特色小镇作为新型城镇化的主力军,体力化威胁仍不可避免。为缓解特色小镇体力化困境,文章基于智力城镇化的相关理论,以辽宁通远堡镇为例,围绕特色产业展开智力化培育的探索。结合链式产业思维,以智力投入、智力主体、智力产出三大环节为基础,以智力要素创新性地打造智力链条,构建可持续的特色产业,带动城镇化转型升级,以期为辽宁省乃至全国特色小镇培育提供借鉴。 展开更多
关键词 智力城镇化 智力投入 智力主体 智力产出 智力链
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Comparative study of nuclear masses in the relativistic mean-field model 被引量:4
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作者 HUA XueMin HENG TaiHua +2 位作者 NIU ZhongMing SUN BaoHua GUO JianYou 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第12期2414-2419,共6页
With experimental masses updated from AME11,the predictive power of relativistic mean-field(RMF) mass model is carefully examined and compared with HFB-17,FRDM,WS*,and DZ28 mass models.In the relativistic mean-field m... With experimental masses updated from AME11,the predictive power of relativistic mean-field(RMF) mass model is carefully examined and compared with HFB-17,FRDM,WS*,and DZ28 mass models.In the relativistic mean-field model,the calculation with the PC-PK1 has improved significantly in describing masses compared to the TMA,especially for the neutron-deficient nuclei.The corresponding rms deviation with respect to the known masses falls to 1.4 MeV.Furthermore,it is found that the RMF mass model better describes the nuclei with large deformations.The rms deviation for nuclei with the absolute value of quadrupole deformation parameter greater than 0.25 falls to 0.93,crossing the 1 MeV accuracy threshold for the PC-PK1,which may indicate the new model is more suitable for those largely-deformed nuclei.In addition,the necessity of new high-precision experimental data to evaluate and develop the nuclear mass models is emphasized as well. 展开更多
关键词 nuclear masses relativistic mean-field model rotational correction
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MATHEMATICAL DESCRIPTION OF GROWTH OF MULTIPLE ROOT BRANCHING STRUCTURE IN A PLANT
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作者 ARUN KUMAR 《International Journal of Biomathematics》 2013年第3期1-10,共10页
An existing growth model of Edelstien is extended and modified for multiple root branching structure or root hairs of any plant. Numerical and analytical solutions for the model are developed and compared. In the deri... An existing growth model of Edelstien is extended and modified for multiple root branching structure or root hairs of any plant. Numerical and analytical solutions for the model are developed and compared. In the derivation it is assumed that multiple root branches are attached to the root surface that acts as a continuous source of new tips. The numerical scheme is derived with anticipation of the fact that comparison with experimental data may necessitate a more complicated model. 展开更多
关键词 Uptake parameter asymptotic matching van Genuchten formula relativewater content.
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On the Essential Conditions of Difference Information and Class Ratio Dispersion of Several Kinds of Data Processing Methods Reducing in Grey Predicting Modelling 被引量:1
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作者 Yong Wei 《Journal of Systems Science and Information》 2006年第4期735-740,共6页
In this paper, author presents the essential conditions of difference information and class ratio dispersion reducing by logarithm and root sequence. They also point out that although new data is in the range suitable... In this paper, author presents the essential conditions of difference information and class ratio dispersion reducing by logarithm and root sequence. They also point out that although new data is in the range suitable of the model, the error after it returns to original state might be great. 展开更多
关键词 logarithmic sequence root sequence difference information class ratio class ratio dispersion
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一年级俄语词汇课教学经验
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作者 厚子明 《开封师院学报(社会科学版)》 1960年第5期41-45,共5页
这篇论文的目的,是把一年来词汇课教学法的点滴体会和经验写出来,这种方法是否合适,都还存在着那些问题,供同志们参考,希提出改进意见,使教学方法不断改进,质量不断提高。 过去一年级词汇课与语法课是齐头并进,是互相配合,语法课内容和... 这篇论文的目的,是把一年来词汇课教学法的点滴体会和经验写出来,这种方法是否合适,都还存在着那些问题,供同志们参考,希提出改进意见,使教学方法不断改进,质量不断提高。 过去一年级词汇课与语法课是齐头并进,是互相配合,语法课内容和它的系统性是据根词汇课的内容而编写的。但编选词汇课教材时,又要注意语法的系统性。在上词汇课之前,先把词汇课文内容语法重点加以讲授,然后在这个基础上讲授词汇课文。过去我们认为这种配合方法很好,可腾出许多时间, 展开更多
关键词 俄语词汇 词汇课 教学经验 一年级 教师 句型 句子 据根 语法课 法关系
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