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系统级封装技术方兴未艾 被引量:2
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作者 郑学仁 李斌 +2 位作者 姚若河 陈国辉 刘百勇 《中国集成电路》 2003年第51期79-82,共4页
本文论述系统级封装SiP与系统级芯片SoC的比较优势,重点介绍叠片式封装和晶圆级封装技术如何有效提高封装密度并解决了传统封装面临的带宽、互连延迟、功耗和总线性能等方面的难题。
关键词 统级封装技术 SIP 磷化硅 统级芯片SoC 比较优势 互连延迟 总线性能 叠片式封装 晶圆封装
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专业英语八级统测的写作审题 被引量:14
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作者 刘云红 张金生 《外语教学》 北大核心 2004年第6期85-88,共4页
审题是完成好写作任务的第一步。专业英语八级统测的写作试题由背景引语、标题和要求三部分构成。它们相互联系,构成一个有机的整体。审题时应循序渐进,把握整体,避免遗漏和偏颇。八级统测写作在审题方面存在的主要问题包括割裂试题各... 审题是完成好写作任务的第一步。专业英语八级统测的写作试题由背景引语、标题和要求三部分构成。它们相互联系,构成一个有机的整体。审题时应循序渐进,把握整体,避免遗漏和偏颇。八级统测写作在审题方面存在的主要问题包括割裂试题各个组成部分之间的关系,错误理解标题意义,背离试题的要求和偏离了设定的主题或观点等。针对这些问题,可采取各种有效的方法加以解决,如培养仔细、严谨的作风,培养对文字信息的破译能力,加强说明文和议论文的写作训练,加强综合能力和素质的培养等。 展开更多
关键词 专业英语 写作 审题
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英语AB级统测对高职学生的心理影响及对策 被引量:2
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作者 刘燕 孟丽 《煤炭高等教育》 2009年第6期120-121,共2页
高等学校英语应用能力考试(英语AB级统测)对考核高职院校学生的英语水平、检查教学大纲的执行情况、推动高职院校的英语教学改革起到了积极的作用,但同时也对高职学生产生了一些积极的和消极的心理影响。了解英语AB级统测对学生的心理影... 高等学校英语应用能力考试(英语AB级统测)对考核高职院校学生的英语水平、检查教学大纲的执行情况、推动高职院校的英语教学改革起到了积极的作用,但同时也对高职学生产生了一些积极的和消极的心理影响。了解英语AB级统测对学生的心理影响,研究对策,是确保高等学校英语应用能力考试有效的途径之一。 展开更多
关键词 AB 高职学生 心理影响
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关于做好英语专业四、八级统测考务管理的思考 被引量:1
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作者 赵红梅 段克勤 《中国校外教育》 2013年第11期115-115,119,共2页
英语专业四、八级统测是全国高校英语专业学生进行的一次大规模标准化的统一测试,工作量大,涉及面广,规范性强。其考务管理工作需要做到严守统测工作管理规定,报名工作做到零差错,精心组织测试,力求做到规范、公正。
关键词 英语专业 考务管理
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我的总统级待遇
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《小哥白尼(趣味科学)》 2006年第6期30-31,共2页
现在心情好多了,天将降大任于斯人也,必先苦其心志,劳其筋骨……啊哈,我是一只太空鱼,太空鱼,太空鱼……喂,给你透漏一点机密,我们的设备可都是量身定做的,包你没见过!
关键词 鱼缸 心情 太空 统级 待遇 设备 心志 宇航员 人工肺 定做
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Conjugated microporous polymers-scaffolded enzyme cascade systems with enhanced catalytic activity
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作者 Zhenhua Wu Jiafu Shi +6 位作者 Boyu Zhang Yushuai Jiao Xiangxuan Meng Ziyi Chu Yu Chen Yiran Cheng Zhongyi Jiang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期213-223,共11页
Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs... Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2))is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2)interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling. 展开更多
关键词 BIOCATALYSIS IMMOBILIZATION Enzyme cascade system Substrate channeling effect Conjugated microporous polymers
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Challenges to Data-Path Physical Design Inside SOC 被引量:2
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作者 经彤 洪先龙 +5 位作者 蔡懿慈 许静宇 杨长旗 张轶谦 周强 吴为民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第8期785-793,共9页
Previously,a single data-path stack was adequate for data-path chips,and the complexity and size of the data-path was comparatively small.As current data-path chips,such as system-on-a-chip (SOC),become more complex,m... Previously,a single data-path stack was adequate for data-path chips,and the complexity and size of the data-path was comparatively small.As current data-path chips,such as system-on-a-chip (SOC),become more complex,multiple data-path stacks are required to implement the entire data-path.As more data-path stacks are integrated into SOC,data-path is becoming a critical part of the whole giga-scale integrated circuits (GSI) design.The traditional physical design methodology can not satisfy the data-path performance requirements,because it can not accommodate the data-path bit-sliced structure and the strict performance (such as timing,coupling,and crosstalk) constraints.Challenges in the data-path physical design are addressed.The fundamental problems and key technologies in data-path physical design are analysed.The corresponding researches and solutions in this research field are also discussed. 展开更多
关键词 physical design data-path bit-sliced structure SYSTEM-ON-A-CHIP giga-scale integrated circuits very-deep-submicron
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System-Level Modeling and Simulation of Force-Balance MEMS Accelerometers 被引量:1
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作者 张宇峰 刘晓为 陈伟平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第5期917-922,共6页
This paper presents two approaches for system-level simulation of force-balance accelerometers. The derivation of the system-level model is elaborated and simulation results are obtained from the implementation of tho... This paper presents two approaches for system-level simulation of force-balance accelerometers. The derivation of the system-level model is elaborated and simulation results are obtained from the implementation of those strategies on the fabricated silicon force-balance MEMS accelerometer. The mathematical model presented is implemented in VHDL- AMS and SIMULINK TM,respectively. The simulation results from the two approaches are compared and show a slight difference. Using VHDL-AMS is flexible,reusable,and more accurate. But there is not a mature solver developed for the language and this approach takes more time, while the simulation model can be easily built and quickly evaluated using SIMULINK. 展开更多
关键词 MEMS force-balance accelerometers system-level simulation mathematical model
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Application of GIS in Ecological Land Type(ELT)mapping--A case in Changbai Mountain area 被引量:2
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作者 肖宝英 代力民 +1 位作者 陈高 邵国凡 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期56-60,84,共5页
This paper depicted the physiographic landscape features and natural vegetation situation of study area (the eastern Jilin Province), and expatiates the definition, basic characters and its development of Ecological L... This paper depicted the physiographic landscape features and natural vegetation situation of study area (the eastern Jilin Province), and expatiates the definition, basic characters and its development of Ecological Land Classification (ELC). Based on the combination of relief map, satellite photography for study area and vegetation inventory data of 480 sample sites, a 5-class and a 15-class ecological land type map was concluded according to 4 important factors including slope, aspect, vegetation and elevation. Ecological Classification System (ECS) is a method to identify, characterize, and map ecosystems. The Ecological Land Type (ELT) was examined and applied initially in eastern Jilin Province. 展开更多
关键词 Ecological Land Type(ELT) Ecological Classification System(ECS) Ecological land classification(ELC) Geographic Information system(GIS)
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加强英语专业四、八级统测的科学性与权威性,全面提高我国外语教学水平 被引量:7
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作者 姚乃强 李绍山 《外语界》 CSSCI 北大核心 1994年第3期9-13,共5页
加强英语专业四、八级统测的科学性与权威性,全面提高我国外语教学水平解放军外国语学院姚乃强,李绍山在国家教委高校外语教学指导委员会及各有关方面和人员的努力下,英语专业四、八级统测经过多年试行,日臻成熟和完善,其权威性日... 加强英语专业四、八级统测的科学性与权威性,全面提高我国外语教学水平解放军外国语学院姚乃强,李绍山在国家教委高校外语教学指导委员会及各有关方面和人员的努力下,英语专业四、八级统测经过多年试行,日臻成熟和完善,其权威性日益提高,影响逐步扩大,取得了令人注... 展开更多
关键词 外语教学 英语专业 教学大纲 教学质量 试卷 全面提高 考试成绩 教学内容 区分度
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Modified embedded-atom interatomic potential for Co-W and Al-W systems 被引量:1
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作者 董卫平 陈铮 Byeong-Joo LEE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期907-914,共8页
A semi-empirical interatomic potential formalism,the second-nearest-neighbor modified embedded-atom method(2NN MEAM),has been applied to obtaining interatomic potentials for the Co-W and Al-W binary system using previ... A semi-empirical interatomic potential formalism,the second-nearest-neighbor modified embedded-atom method(2NN MEAM),has been applied to obtaining interatomic potentials for the Co-W and Al-W binary system using previously developed MEAM potentials of Co,Al and W.The potential parameters were determined by fitting the experimental data on the enthalpy of formation,lattice parameter,melting point and elastic constants.The present potentials generally reproduce the fundamental physical properties of the Co-W and Al-W systems accurately.The lattice parameters,the enthalpy of formation,the thermal stability and the elastic constants match well with experiment and the first-principles results.The enthalpy of mixing and the enthalpy of formation and mixing of liquid are in good agreement with CALPHAD calculations.The potentials can be easily combined with already-developed MEAM potentials for binary cobalt systems and can be used to describe Co-Al-W-based multicomponent alloys,especially for interfacial properties. 展开更多
关键词 modified embedded-atom method Co-W system Al-W system atomistic simulation
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今日(八月十六日)安国药市行情点评
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作者 李诚 《中国现代中药》 CAS 1999年第6期32-34,共3页
红参白参洋参党参如处子,市价平静如水。北沙参市价安国3.50元有售,十月产新供大于求,势必跌到3元以下。熟悉北沙参的药商知道:86年跌到3元,88年猛涨到24元,94年跌到2元,96年涨到24—26元。
关键词 安国药市 行情 市价 黄连 北沙参 统级 草市 调料 积量 集散地
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今天(四月十五日) 安国市场中药材价格走势与分析
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作者 李诚 《中国现代中药》 CAS 1999年第2期33-35,共3页
人参价格结构性调整,白参价格稳定,红参上扬,红参小抄由65元升至80元。不过人参毕竟价格高峰期已过,今后两三年是低谷期。西洋参价格下跌之势快如脱兔,正品国产西洋参统货产地有大货急于脱手,要价200元。西洋参和人参双双步入谷底,愈发... 人参价格结构性调整,白参价格稳定,红参上扬,红参小抄由65元升至80元。不过人参毕竟价格高峰期已过,今后两三年是低谷期。西洋参价格下跌之势快如脱兔,正品国产西洋参统货产地有大货急于脱手,要价200元。西洋参和人参双双步入谷底,愈发造就跌势。党参价格高悬,潞党纹党白条党均上浮2元,其实大货囤积数量颇丰,安国数百吨, 展开更多
关键词 安国市场 价格走势 中药材 市价 烂市 安国药市 压货 行情表 统级 天麻
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Pattern and Significance of Seedling Development in Titanotrichum oldhamii (Gesneriaceae)
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作者 王印政 李振宇 +1 位作者 潘开玉 邹秀红 《Acta Botanica Sinica》 CSCD 2002年第8期903-907,共5页
The seedling development of Titanotrichum oldhamii (Hemsl.) Solereder has been investigated to provide insight into the evolution and systematic position of Titanotrichum. In T. oldhamii, the size differentiation of t... The seedling development of Titanotrichum oldhamii (Hemsl.) Solereder has been investigated to provide insight into the evolution and systematic position of Titanotrichum. In T. oldhamii, the size differentiation of the two cotyledons begins while the hypocotyl grows. However, both of the two cotyledons develop normally and locate at the same level. Finally, the two cotyledons are almost equal in size. The aerial shoot (including stem and leaves) is produced from the permanent activity of the apical meristem in the plumular bud. Even though the seedling development in Titanotrichum basically conforms to the general growth pattern of the seedling in the Cyrtandroideae, it is remarkably different from that of other Cyrtandroideae. Based on the revealed evidence in seedling development in Titanotrichum and other comparative data, the authors have evaluated the possible evolutionary pathway of Titanotrichum and further discussed the familial placement of this genus. 展开更多
关键词 seedling development COTYLEDON functional evolution familial placement Titanotrichum GESNERIACEAE
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食用菌市场近期行情
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《农村百事通》 2005年第12期24-24,共1页
关键词 食用菌市场 行情 统级 品种规格 木屑 平菇 鸡腿菇 花菇 黑色
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东莞市果菜副食交易市场近期价格
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《农村百事通》 2004年第11期13-13,共1页
关键词 东莞市 果菜 交易市场 富士苹果 海南 提子 统级 品名 泰国 枇杷
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东莞市某菜副食交易市场近期价格行情
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《农村百事通》 2002年第4期12-12,共1页
关键词 东莞市 交易市场 东城区 发价 苹果 香蕉 酥梨 统级 品名 水晶
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食用菌市场近期行情
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《农村百事通》 2004年第24期25-25,共1页
关键词 食用菌市场 木屑 茶薪菇 统级 毛木耳 姬松茸 金针菇 行情 鸡腿菇 黑虎掌
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绝不当头
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作者 老莫 《商务周刊》 2001年第4期53-54,共2页
寻常人等总欲山登绝顶我为峰,而当你真正登顶之后,等待你的是什么呢?除去孤独还是孤独。我们平常对所谓领导人物怀着敬畏之心其实大错特错了,在内心深处而言。
关键词 独得 内心深处 领导人物 中庸 大错 总设计师 朋友 诸侯 统级 万世师表
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东莞市果菜副食交易市场近期价格
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《农村百事通》 2004年第10期13-13,共1页
关键词 东莞市 果菜 交易市场 富士苹果 海南 提子 统级 品名 泰国 批发价
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