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The Journal of China Universities of Posts and Telecommunications 2004年第z1期11卷 55-61页

作者： LI Zuo-wei~1, YANG Yi-xian~1, YUAN Dong-feng~2. HU Zheng-ming~1 1.Information Security Center,beijing University of Posts and Telecommunications, beijing 100876, P.R. China 2.{2. of Information Science and Engineering, Shandong University, Jinan 2.0100, P.R. China Information Security Center Beijing University of Posts and Telecommunications Beijing 100876 P.R. China school of Information Science and Engineering Shandong University Jinan 250100 P.R. China

In this paper, we propose a novel Unequal Error Protection (UEP) scheme with two levels for image transmission using Multilevel Codes (MLC). By providing the best protection for the most important data, the final recovered image quality is remarkably improved both in visual effect and in Peak Signal to Noise power Ratio (PSNR) performance.

关键词： rayleigh fading channel image transmission inequal error protection multilevel coding

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氢氟醚结构和振动光谱的密度泛函理论研究

石油化工 2005年第1期34卷 65-69页

作者：肖翠玲徐文国唐炼北京理工大学理学院北京100081 石油大学(北京)数理系北京102200

采用密度泛函理论(DFT)方法(BHLYP,BLYP,B3.YP,B3.W91,BPW91)对二甲醚(CH3.CH3.和几种氢氟醚(CH3.CF3.CHF2.CHF2.CHF2.CF3.CH3.CF2.F3.进行了几何构型优化以及分子的谐振频率和红外吸收强度的计算.计算基组选用双ξ加极化函数和弥散函数基组(DZP++).通过与实验值的比较,B3.YP方法对几何构型和谐振频率的预测都取得了比较满意的结果.谐振频率的计算值与实验值的平均相对偏差小于2..800～1 3.0cm-1区域红外吸收强度之和的计算结果表明,随着分子中F原子比例的增加,在该区域的红外吸收强度变大.CH3.CH3.CH3.CF3.CH3.CF2.F3.该区域的红外吸收强度较小.

关键词：氢氟醚密度泛函理论谐振频率红外吸收强度

Effect of Finish Rolling Temperature on Microstructure and Mechanical Properties of High Grade Pipeline Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 625-628页

作者： TANG Xing-chang,KANG Yong-lin,BO Yan-yan (school of Materials Science and Engineering,State Key Laboratory for Advanced Metals and Materials,University of Science and Technology beijing,beijing 100083.China) Univ Sci & Technol beijing State Key Lab Adv Met & Mat Sch Mat Sci & Engn Beijing 100083 Peoples R China

The correlation among finish rolling temperature (FRT),microstructure and mechanical property of the high grade pipeline steel was investigated in this *** microstructure of the steels with different finish rolling temperatures was observed with scanning electronic microscope (SEM) and transmission electronic microscope (TEM).The martensite/austenite (M/A) islands distribution was fixed by colour metallography,and the mechanical properties of the steels were tested with quasi-static tensile testing *** result shows that the fraction of M/A island increased with the finish rolling temperature decreasing,and when the finish rolling temperature is 800℃,the mechanical properties are the best.

关键词： high grade pipeline steel finish rolling temperature martensite/austenite island

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关于切尔诺贝利事件核致冬季和大气污染研究

核电子学与探测技术 1989年第6期9卷 361-365页

作者：朱岗崑中国科学院地球物理研究所

一、切尔诺贝利事件苏联切尔诺贝利核电站(51°17′N,3.°15′E)事故发生后,在核领域和广大公众中引起了强烈的震动和反响。该事故发生于1986年4月2.日2.时2.0}(地方时间为4月2.日0时2.0}),由于第四号发电机组的失灵和失控,造成反应堆... 详细信息

一、切尔诺贝利事件苏联切尔诺贝利核电站(51°17′N,3.°15′E)事故发生后,在核领域和广大公众中引起了强烈的震动和反响。该事故发生于1986年4月2.日2.时2.0}(地方时间为4月2.日0时2.0}),由于第四号发电机组的失灵和失控,造成反应堆本身的损坏和放射性物质的漏泄。二年多来世界各国围绕这个事件作了许许多多的测量和研究,下面仅就它所漏泄放射性灰尘,在大气中污染和扩散的情况作一简短的综述。

关键词：切尔诺贝利核致冬季大气污染

Microstructure and Properties of 980MPa UltrafineGrained Cold Rolled Dual-Phase Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 316-319页

作者： HAN Qi-hang,KANG Yong-lin,ZHAO Xian-meng (school of Materials Science and Engineering,State Key Laboratory for Advanced Metals and Materials,University of Science and Technology beijing,beijing 100083.China) Univ Sci & Technol beijing Sch Mat Sci & Engn State Key Lab Adv Met & Mat Beijing 100083 Peoples R China

Two kinds of 980MPa grade cold rolled dual phase steels have been developed by designing C-Si-Mn and C-Si-Mn-Nb alloy *** microstructure of martensite in Nb-free steel is consisted of lath martensite and twined martensite with the volume fraction of 67%.However,the main hard phase in Nb-containing one is twined martensit with the volume percent of 59%.The size of martensite islands in Nb-containing steel is from 1μm to 3.m,and the size of NbC precipitates is from 15nm to *** to Nb-containing steel,the yield strength,tensile strength,yield ratio and elongation are 501MPa,103.MPa,0.48 and 17.5% ***,Nb-containing steel has higher working hardening rate value above the critical strain 6.5%.And it decreases slowly with increasing the *** is mainly because of ultrafine grain size and nano-precipitates in ferrite,which improves the compatibility of phases and reduces the stress concentration at the phase interface.

关键词： ultra-high-strength dual-phase steel ultra-fine grain microstructure properties

Lifetime measurements and test for chirality in 106Ag

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Lifetime measurements and test for chirality in 106Ag

Fabrication and Characterization of GCO Electrolyte Films

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： ZHENG Yun~(1 1)) ZHU Li-Hua~(2.3.2.) WU Xiao-Guang~(1)) He Chuang-Ye~(1)) LI Guang-Sheng~(1)) WANG Lie-Lin~(1,4)) Yu Bei-Bei~(1)) Yao Shun-He~(1)) Zhang Biao~(1,3.) Xu Chuan~(5)) Wang Jian-Guo~(6)) Gu Long~(6)) 1(China Institute of Atomic Energy,{2. 102.13.China) 2.Department of Physics,Beihang University,{2. 100191,China) 3.Faculty of Science,ShenZhen University,Shenzhen 518060,China) 4(Department of Physics,Jilin University,Changchun 13.02.0}China) 5(school of Physics,Peking University,{2. 100871,China) 6(Department of Physics,Tsinghua University,{2. 100084,China)

The high-spin states in the doubly odd nucleus Ag were populated via the heavy-ion fusionevaporation reaction Mo(B,5n)Ag at beam energy of *** target consisted of a 1.56mg/cm- thick Mo backed on lead with a thickness of 8.03.g/*** have been measured by means of Doppler-shift attenuation method for states in one positive parity magnetic dipole（M1） band and chiral candidate bands in *** B（M1） values for transitions in positive band as a function of rotational frequency w obtained from present experiment are compared with the precious data and TAC calculations in Fig.1. The present experimental results are in good agreement with the calculations and the previous *** comparison suggesting that the total angular momentum can be mainly explained through the shears mechanism. Reduced transition strengths B（E2. in chiral candidate bands obtained from the present experiment are shown in *** experimental B（E2. values are larger in side band than in yrast band as well as the B（M1） *** experimental results do not support the presence of static chirality in Ag.

关键词： High spin states Lifetime measurement Chirality

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稀有金属材料与工程 2006年第S3期 530-532页

作者： Yuxing Xu~1 Zilong Tang~1 Zhongtai Zhang~1 Zhigang Zhou~1 Lihai Xu~2.(1.State Key Laboratory of New Ceramic and Fine Processing,Department of Materials Science and Engineering,Tsinghua University,beijing 100084,China) (2.Center of Condensed Matter Physics and Material Physics,school of Science,Beihang University,beijing 100083.China)

Gd-doped Ceria (GCO:Gd0.1Ce0.9O1.95) sensing films have been fabricated successfully on glasses and porous Al2.3.eramic substrates by RF magnetron *** conditions such as power and temperature have been investigated and the sample was characterized in detail by XRD,SEM and AC impedance *** results show that the films grow preferentially along the （111） compact plane with a pure fluorite structure and the crystal grain grows more sufficiently with increasing of the annealing *** addition,a high oxygen ion conductivity of 2.2.×***-1is achieved at 800℃.

关键词： electrolyte film GCO RF magnetron sputtering oxygen conductivity

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北京市人力资本对经济增长效应的实证研究

上海商学院学报 2011年第5期12卷 63-66页

作者：李超群中国社科院研究生院政府政策系中国北京102488

应用包含人力资本要素的C-D生产函数模型,以1996—2.09年的相关数据为基础,对北京市人力资本与经济增长的效应进行了实证研究,结果表明,人力资本平均水平的提高,对于北京市的经济增长产生了显著的正效应。此外,实证结果还表明,固定资产... 详细信息

应用包含人力资本要素的C-D生产函数模型,以1996—2.09年的相关数据为基础,对北京市人力资本与经济增长的效应进行了实证研究,结果表明,人力资本平均水平的提高,对于北京市的经济增长产生了显著的正效应。此外,实证结果还表明,固定资产投资对于北京市经济增长的作用并不显著,劳动力人口数量对北京市经济增长的作用则相对显著。

关键词：人力资本经济增长效应

Feature Technology in Product Modeling

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武汉理工大学学报 2006年第S3期28卷 1144-1147页

作者： ZHANG Xu NING Ruxin (Digital Product Development and Manufacturing Lab,school of Mechanical and Vehicular Engineering,beijing Institute of Technology,beijing 100081,China,) Digital Product Development and Manufacturing Lab School of Mechanical and Vehicular EngineeringBeijing Institute of TechnologyBeijing 100081China

A unified feature definition is *** is form-concentrated,and can be used to model product func- tionalities,assembly relations,and part *** feature model is given and a feature classification is introduced including functional,assembly,structural,and manufacturing features.A prototype modeling system is developed in Pro/ENGINEER that can define the assembly and user-defined form features.

关键词： feature product modeling feature-based design feature mapping

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海运数据仓库的设计与实现

计算机辅助工程 2003年第3期12卷 40-44页

作者：段成华刘娟中国科学院研究生院信息学院北京100039

海运行业竞争激烈,业务流程复杂,建立数据仓库系统来辅助决策是十分必要的。本文通过一个海运数据仓库的建立过程,来介绍设计数据仓库的主要步骤。

关键词：海运数据仓库数据库数据挖掘数据装载数据更新数据源设计