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一种新型LDI复合对位标靶在HDI生产中的应用 被引量:1
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作者 罗登峰 李华平 李益斌 《印制电路信息》 2017年第4期56-60,共5页
HDI板中同时存在激光孔及机械通孔,且两种孔的对位基准点与设备精度不同,很难同时保证激光孔及机械通孔的对准度。本文主要介绍了一种新型的LDI复合对位标靶的设计,通过制程中对位方式的优化重组,以此提升激光孔与机械通孔的涨缩匹配性。
关键词 复合对位标靶 激光孔 机械通孔 位移差异性 对位 涨缩
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从数理创作思维看20世纪音乐节奏结构力 被引量:1
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作者 肖楠楠 《南京艺术学院学报(音乐与表演版)》 CSSCI 2009年第3期147-152,共6页
20世纪西方音乐作品中,节奏被逐步提升到主导音乐发展的位置,音乐的节奏结构已成为音乐家们必须解决的最大课题之一。20世纪音乐节奏何以具有如此强大的结构功能作用?这种能量是如何生成的?文章将对那些在节奏创作上基于一定数理逻辑的... 20世纪西方音乐作品中,节奏被逐步提升到主导音乐发展的位置,音乐的节奏结构已成为音乐家们必须解决的最大课题之一。20世纪音乐节奏何以具有如此强大的结构功能作用?这种能量是如何生成的?文章将对那些在节奏创作上基于一定数理逻辑的具有代表性的20世纪音乐作品进行分析解读,探寻20世纪节奏结构的魅力所在。 展开更多
关键词 20世纪音乐节奏 结构力 数理逻辑 复合对位 自由式变化节奏
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Contrastive thematic analysis in research articles
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作者 张丽杰 王祁 《Sino-US English Teaching》 2010年第11期40-43,61,共5页
Based on the theory of thematic complexity, a contrastive analysis on 2 sections selected from research articles-method and discussion, was conducted. The differences and similarities between the 2 sections in simple ... Based on the theory of thematic complexity, a contrastive analysis on 2 sections selected from research articles-method and discussion, was conducted. The differences and similarities between the 2 sections in simple theme, multiple theme, textual theme, interpersonal theme, topical theme and thematic progression were analyzed and concluded. The author believes that the causes of the differences and similarities are the different genre features of the 2 sections and the academic features of the materials selected. 展开更多
关键词 thematic complexity research article GENRES contrastive analysis
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Position Group Contribution Method for Predicting the Normal Boiling Point of Organic Compounds 被引量:7
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作者 王强 马沛生 +1 位作者 王昶 夏淑倩 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第2期254-258,共5页
A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distr... A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distribution function.It could distinguish most of isomers that include cis-or trans-structure from organic compounds.Contributions for hydrocarbons and hydrocarbon derivatives containing oxygen,nitrogen,chlorine,bromine and sulfur,are given.Compared with the predictions,results made use of the most common existing group contribution methods,the overall average absolute difference of boiling point predictions of 417 organic compounds is 4.2 K;and the average absolute percent derivation is 1.0%,which is compared with 12.3 K and 3.2% with the method of Joback,12.1 K and 3.1% with the method of Constantinou-Gani.This new position contribution groups method is not only much more accurate but also has the advantages of simplicity and stability. 展开更多
关键词 normal boiling point PREDICTION position group contribution
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Composition Operator from Logarithmic Bloch-Type Space to Bergman Space on Unit Polydisc
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作者 张利 曾红刚 《Transactions of Tianjin University》 EI CAS 2011年第6期450-453,共4页
In order to investigate the boundedness or compactness of composition operator from the logarithmic Bloch-type space to the Bergman space on the unit polydisc, the classic Bergman norm is firstly changed into another ... In order to investigate the boundedness or compactness of composition operator from the logarithmic Bloch-type space to the Bergman space on the unit polydisc, the classic Bergman norm is firstly changed into another equivalent norm. Then according to some common inequalities, the properties of logarithmic Bloch-type space and the absolute continuity of the general integral, the conditions which the symbol map must meet when the composition operator is bounded or compact are obtained after a series of calculations, and the boundedness and compactness are proved to be equivalent. 展开更多
关键词 composition operator logarithmic Bloch-type space Bergman space COMPACTNESS BOUNDEDNESS
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Parameters of static response of carbon fiber reinforced polymer(CFRP) suspension cables
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作者 王立彬 吴勇 Mohammad Noori 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3123-3132,共10页
The feasibility of longer spans relies on the successful implementation of new high-strength light weight materials such as carbon fiber reinforced polymer(CFRP). First, a dimensionless equilibrium equation and the co... The feasibility of longer spans relies on the successful implementation of new high-strength light weight materials such as carbon fiber reinforced polymer(CFRP). First, a dimensionless equilibrium equation and the corresponding compatibility equation are established to develop the cable force equation and cable displacement governing equation for suspension cables, respectively. Subsequently, the inextensible cable case is introduced. The formula of the Irvine parameter is considered and its physical interpretation as well as its relationship with the chord gravity stiffness is presented. The influences on the increment of cable force and displacement by λ2 and load ratio p′ are analyzed, respectively. Based on these assumptions and the analytical formulations, a 2000 m span suspension cable is utilized as an example to verify the proposed formulation and the responses of the relative increment of cable force and cable displacement under symmetrical and asymmetrical loads are studied and presented. In each case, the deflections resulting from elastic elongation or solely due to geometrical displacement are analyzed for the lower elastic modulus CFRP. Finally, in comparison with steel cables, the influences on the cable force equation and the governing displacement equation by span and rise span ratio are analyzed. Moreover, the influences on the static performance of suspension bridge by span and sag ratios are also analyzed. The substantive characteristics of the static performance of super span CFRP suspension bridges are clarified and the superiority and the characteristics of CFRP cable structure are demonstrated analytically. 展开更多
关键词 suspension bridge carbon fiber reinforced polymer (CFRP) main cable steel suspension cable static response
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