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Genomics, Proteomics & Bioinformatics 2003年第2期1卷 87-89页

作者： Xingmin Ligraduate School, Chinese Academy of Sciences,{1., chinaXin Zhang (beijing Language and Culture {4., beijing 1.0083, china) and Wei Gong (beijing Genomics Institute, beijing 1.1.00, china) graduate School Chinese Academy of Sciences Beijing 100039 China

The terms "science" (Hanyu Pinyin: Kexue) and "technology" (Jishu), in western languages, are usually used separately with different meanings or together as "science and technology". However, they are often mentioned as "Kexue Jishu", or even abbreviated as "sci-tech (Keji)" in china (It is used in a similar way in Japan). It not only causes great confusion in conceptual content, but also very misleading

关键词： that on as it Science and Technology Is Not Simply Equal to Sci-Tech for been into of

Effect of Crystallinity on Electrochemical Insertion/Extraction of Li in Transition Metal Oxides Part Ⅱ: TiO_2, V_2O_5 and MoO_3

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Journal of Materials Science & Technology 2000年第1期16卷 5-14页

作者： Tomoki TSUMURA and Michio INAGAKI (graduate School of Engineering, Hokkaido {1. Kita-ku, Sapporo, 060-8628, Japan) graduate School of Engineering Hokkaido University Kita-ku Sapporo 060-8628 Japan NARD Institute Ltd. 2 Nishinagasu Amagasaki 660-0805 Japan Aichi Institute of Technology Yakusa Toyota 470-0392 Japan

Electrochemical insertion/extraction of Li on cathode materials of anatase type TiO_2, quasilayered structure V_2O_5 and layered structure MoO_3 was measured on samples of which structures were well characterized and showed a wide range of crystallinity. On the basis of experimental results on structure, morphology and charge-discharge characteristics, the effect of crystallinity of the cathode materials on electrochemical Li insertion/extraction pedermance was discussed. These three transition metal oxides were classified as one group on the basis of whether the crystallinity of these oxides affects to the performance or not; LiMn_2O_4.and LiCo_(0.5)O_2 belongs to the former group and TiO_2, V_2O_5 and MoO_3 to the latter.

关键词： Li Effect of Crystallinity on Electrochemical Insertion/Extraction of Li in Transition Metal Oxides Part V2O5 and MoO3

Numerical modeling of gravitational erosion in rill systems

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International Journal of Sediment Research 2011年第4期26卷 403-415页

作者： Peng HAN,Jin-Ren NI,Ke-Bin HOU,Chi-Yuan MIAO,and Tian-Hong LI 1.Assoc.Prof,2 Prof.,3 Master,4.Dr.,5 Assoc.Prof.,Department of Environmental Engineering,Peking {1.,beijing 1.0871.P.R.china,The Key Laboratory of Water and Sediment Sciences,Ministry of Education,P.R.china, [a] Assoc. Prof. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China [b] Prof. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China [c] Master Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China [d] Dr. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China [e] Assoc. Prof. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China

A self-organizing model was developed for simulating rill erosion process on slopes with particular attention to the role of gravitational *** a complete simulation circle,processes such as precipitation,infiltration,runoff,scouring,gravitational erosion and elevation variation were fully *** time(or runoff time) was regarded as iteration benchmark in the *** specify the contribution of gravitational erosion to the process of rill formation and development,a gravitational erosion module was inserted into the *** erosion in rill development was regarded as a Gaussian random process.A model was calibrated by our experimental data,and further validated satisfactorily with 22 runs of experimental results from different investigators. Systematic comparison was made between sediment yields with and without consideration of gravitational erosion *** was demonstrated that the model could reasonably simulate the rill erosion process under a variety of slope gradients,rainfall intensities and soil conditions upon the gravitational erosion being ***,the role of gravitational erosion on sediment yields in rill systems varies significantly under different conditions,although it is of the utmost importance in steeper *** process of gravitational erosion in rill development was studied by a newly-defined parameter a>,which is defined as the volume ratio of gravitational erosion over hydraulic-related *** gravitational contribution to the total erosion could be over 50%for the rill systems with higher rainfall intensity and steeper slopes.

关键词： Self-organizing model Rill erosion Gravitational erosion Gaussian noise

A Cumulant-Based Beamforming Algorithm for CDMA Frequency-nonselective Fading Channel

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Wuhan university Journal of Natural Sciences 2002年第3期7卷 327-332页

作者： Yang Wei 1., Cheng Shi\|xin 2 1. School of Electronics and Information Engineering, Northern Jiaotong university, {1. 1.004., china 2. National Mobile Communications Research Laboratory, Southeast university, Nanjing 21.096, Jiangsu, china Northern Jiaotong university School of Electronics and Information Engineering Beijing China (GRID:grid.181531.f) (ISNI:***) Southeast university National Mobile Communications Research Laboratory Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***)

A cumulant-based beamforing technique for synchronous CDMA system with decorrelator is presented. With decorrelating detector the proposed algorithm has the advantages that the steering vector of desired user’s can be estimated independently by eliminating all the other resolved signal interferences. Furthermore employing cumulant-based signal processing technique the steering vector of the decoupled signals can be estimated blindly. Simulation results show that the cumulant-based beamformer demonstrates excellent performance.

关键词： antenna array CDMA beamforming cumulant

BLOCK ADAPTIVE RECURSIVE ALGORITHM FOR VIDEO CONFERENCE CODING

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Journal of Electronics(china) 1996年第2期13卷 140-146页

作者： Tu Guofang(graduate School, {1. of Science and Technology of china, beijing 1.0039)Zhang Can(704.Institute, Company of Aero-Space Industry, {4. 1.0076)

This paper presents a new motion estimation algorithm for video conference signal coding. This type of algorithm is called block adaptive recursive algorithm (BARA). Simulation results show that this new algorithm has... 详细信息

关键词： Motion estimation Block adaptive recursive algorithm Motion compensated image coding

Carbon sequestration within millet phytoliths from dry-farming of crops in china

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Carbon sequestration within millet phytoliths from dry-farmi...

中国科学院地质与地球物理研究所第1.届（201.年度）学术年会

作者： ZUO XinXin~(1.2*) & LU HouYuan~1.1.Key Laboratory of Cenozoic Geology and Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing 1.0029,{1. 2 graduate university of Chinese Academy of Sciences,beijing 1.004.,china

Phytoliths are noncrystalline minerals that form inside cells and cell walls of different parts of *** carbon in living cells can be occluded in phytoliths during plant *** has been documented that the occluded carbon within phytoliths is an important long-term terrestrial carbon reservoir that has a major role in the global carbon *** millet and foxtail millet have become typical diy-farming crops in china since the Neolithic *** study of carbon conservation within phytoliths in these crops could provide insights into anthropogenic influences on the carbon *** this study,we analyzed the carbon content in phytoliths of common millet and foxtail *** results indicated that(1. common millet and foxtail millet contained 0.1.6%±0.070%and 0.1.9%±0.085%phytohfh-occluded carbon(PhytOC) on a dry mass basis,respectively;(2) based on the mean annual production of common millet and foxtail millet in the last 1. years,the phytolith occluded carbon accumulation rate of common millet and foxtail millet was approximately 0.023±0.01. and 0.020±0.01. t CO ha a respectively;(3) assuming a similar phytolith occluded carbon accumulation rate as for common millet(the highest accumulation rate was 0.038 t CO ha a), this could result in the sequestration of 2.37×1. t CO per year for the 62.{1.1. ha dry-farming crops in *** there was a decline in the annual production rate and planting area of foxtail millet during 1.{1. to 2008,the total phytolith carbon sequestration rate was 7×l0 t CO within the 60-year ***,phytolith occluded carbon has not yet been fully considered as a global carbon ***,this carbon fraction is probably one of the best candidates for the missing carbon sink.

关键词： phytoliths carbon sequestration dry-farming phytolith occluded carbon PhytOC

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急倾斜煤层地下气化数学模型的研究

燃料化学学报 2003年第3期31卷 193-198页

作者：杨兰和梁杰中国矿业大学资源与地球科学学院江苏徐州221008 中国矿业大学化工与环境工程系北京100083

煤炭地下气化产气过程与气化炉体的温度分布和渗流条件密切相关。根据急倾斜煤层赋存条件和气化过程的特点,建立了急倾斜煤层地下气化数学模型。介绍了模型参数的确定方法,采用控制容积方法对模型进行了求解,并在模型实验的基础上,对计... 详细信息

煤炭地下气化产气过程与气化炉体的温度分布和渗流条件密切相关。根据急倾斜煤层赋存条件和气化过程的特点,建立了急倾斜煤层地下气化数学模型。介绍了模型参数的确定方法,采用控制容积方法对模型进行了求解,并在模型实验的基础上,对计算结果进行了分析。从温度场分布来看,计算值略高于实测值,各测点相对误差基本均在1.%以内。根据模拟计算结果,随着气化通道长度增加,煤气热值提高,但在还原区以后,提高的幅度减小,温度场对煤气热值产生显著影响。由于受温度的影响,在高温区,煤气组分浓度场实测值的变化梯度大于计算值。结果表明,模拟值与实验值能够较好地相吻合,说明对急倾斜煤层地下气化温度场和浓度场的数值模拟是合理的。

关键词：急倾斜煤层煤炭地下气化温度场浓度场数学模型

PARALLE DOMAIN DECOMPOSITION ALGORITHMS FOR A GENERALIZED STOKES PROBLEM

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Systems Science and Mathematical Sciences 1994年第2期7卷 153-168页

作者： CHU Delin ZHOU Fangjun(Department of Applied Mathematics, Tsinghua university, {1. 1.0084. china)

ＰＡＲＡＬＬＥＤＯＭＡＩＮＤＥＣＯＭＰＯＳＩＴＩＯＮＡＬＧＯＲＩＴＨＭＳＦＯＲＡＧＥＮＥＲＡＬＩＺＥＤＳＴＯＫＥＳＰＲＯＢＬＥＭ￥ＣＨＵＤｅｌｉｎ；ＺＨＯＵＦａｎｇｊｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＭａｔ... 详细信息

ＰＡＲＡＬＬＥＤＯＭＡＩＮＤＥＣＯＭＰＯＳＩＴＩＯＮＡＬＧＯＲＩＴＨＭＳＦＯＲＡＧＥＮＥＲＡＬＩＺＥＤＳＴＯＫＥＳＰＲＯＢＬＥＭ￥ＣＨＵＤｅｌｉｎ；ＺＨＯＵＦａｎｇｊｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＭａｔｈｅｍａｔｉｃｓ，Ｔｓｉｎｇｈｕａ...

关键词： Domain decomposition trace average operator convergence condition number a generalized Stokes problem.

Choice of Optimal Trimming Proportion by the Random Weighting Method

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Acta Mathematica Sinica,English Series 1996年第3期12卷 326-336页

作者： Shi Jian Zheng Zhongguo, Department of Probability and Statistics Peking university {1., 1.0871.2} 北京大学概率统计系北京

In this paper, a strongly consistent estimation of the optimal trimming proportion in trimmed mean is found by the random weighting method. In addition, using the same method a strongly consistent estimation for the d... 详细信息

关键词： Trimmed mean Trimming proportion Bootstrap Random weighting