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Above-and belowground biomass in relation to envi- ronmental factors in temperate grasslands, Inner Mongolia

Science china(Life Sciences) 2008年第3期51卷 263-270页

作者： MA WenHong1,2. YANG YuanHe1, HE JinSheng1, ZENG Hui1,2.& FANG JingYun1 1 Department of Ecology, College of Urban and Environmental Sciences, Peking university, Beijing 100871, china 2.School of Environment & Urban Study, Peking university shenzhen graduate School, shenzhen 518055, china 1. Department of Ecology College of Urban and Environmental Sciences Peking University Beijing 100871 China 2. School of Environment & Urban Study Peking University Shenzhen Graduate School Shenzhen 518055 China

Above- and belowground biomasses of grasslands are important parameters for characterizing re- gional and global carbon cycles in grassland ecosystems. Compared with the relatively detailed in- formation for aboveground biomass (AGB), belowground biomass (BGB) is poorly reported at the re- gional scales. The present study, based on a total of 113 sampling sites in temperate grassland of the Inner Mongolia, investigated regional distribution patterns of AGB, BGB, vertical distribution of roots, and their relationships with environmental factors. AGB and BGB increased from the southwest to the northeast of the study region. The largest biomass occurred in meadow steppe, with mean AGB and BGB of 196.7 and 1385.2.g/m2. respectively; while the lowest biomass occurred in desert steppe, with an AGB of 56.6 g/m2.and a BGB of 301.0 g/m2. In addition, about 47% of root biomass was distributed in the top 10 cm soil. Further statistical analysis indicated that precipitation was the primary determinant factor in shaping these distribution patterns. Vertical distribution of roots was significantly affected by precipitation, while the effects of soil texture and grassland types were weak.

关键词： temperate grasslands aboveground biomass (AGB) belowground biomass (BGB) spatial pattern vertical distribution precipitation

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Ground state properties of La isotopes in reflection asymmetric relativistic mean field theory

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1574-1578页

作者： WANG Nan1 & GUO Lu2.1 College of Physics,shenzhen university,shenzhen 518060,china 2.Department of Physics,Faculty of Science,university of Tokyo,Tokyo 113-0033,Japan College of Physics Shenzhen University Shenzhen 518060 China Department of Physics Faculty of Science University of Tokyo Tokyo 113-0033 Japan

The ground state properties of La isotopes are investigated with the reflection asymmetric relativistic mean field(RAS-RMF) *** calculation results of binding energies and the quadrupole moments are in good agreements with the *** calculation results indicate the change of the quadrupole deformation with the nuclear mass *** "kink" on the isotope shifts is observed at A = 139 where the neutron number is the magic number N = *** is also found that the octupole deformations may exist in the La isotopes with mass number A ～ 145-155.

关键词： reflection asymmetric relativistic mean field(RAS-RMF) theory nuclear deformation binding energy

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THz-TDS signal analysis and substance identification via the conformal split

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Science china(Information Sciences) 2012年第1期55卷 49-63页

作者： XIE WeiXin1,2.LI Jing1,2.PEI JiHong2.1School of Electronic Engineering,Xidian university,Xi'an 710071,china 2.ntelligent Information Institute,{2. university,{2. 518060,china 1. School of Electronic Engineering Xidian University Xi’an 710071 China2. Intelligent Information Institute Shenzhen University Shenzhen 518060 China

A terahertz time-domain spectroscopy(THz-TDS)imaging system can obtain high-dimensional signals with substance fingerprint *** introducing geometric algebra,a novel signal analysis approach to THz-TDS signals is developed based on an optical physical *** this approach,signals are represented with vectors in the high-dimensional real vector *** distribution properties and algebraic relationships of THz-TDS signals are *** is proved that every complex refractive index of substances relates to a unique 2.blade,the vectors corresponding to the samples of the same substance are collinear and belong to the intrinsic 2.blade of the *** decomposed through the conformal split with respect to a 2.blade,THz-TDS signals of high dimensionality can be related to vectors in a 2.dimensional *** on the conformal split properties we deduced,two criteria for substance identification on the basis of THz-TDS signals are ***,a novel substance identification method via the conformal split is *** the method,the 2.blade related to each "known" substance is calculated with two vectors corresponding to THz-TDS signals measured from samples of the substance but with dierent *** the conformal split with respect to those 2.blades,an identified vector corresponding to a THz-TDS signal is linearly related to the vector in a 2.dimensional *** substance of a sample can be identified using criteria on the projected vectors in the *** method can contribute to accurate classification and ***,two experiments are presented that show the feasibility and accuracy of this method.

关键词： terahertz time-domain spectroscopy substance identification geometric algebra conformal split

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Theory and verification of operator design methodology

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Science china(Information Sciences) 2012年第2期55卷 480-490页

作者： HU ZiYi1,ZHAO Yong1,WANG XinAn1,HUANG Ru2.WANG Teng1 & ZHANG Xing2.1Key Lab of Integrated Microsystem Science and Engineering Applications,Peking university shenzhen {2. School,shenzhen 518055,china 2.nstitute of Microelectronics,Peking university,Beijing 100871,china 1. Key Lab of Integrated Microsystem Science and Engineering Applications Peking University Shenzhen Graduate School Shenzhen 518055 China2. Institute of Microelectronics Peking University Beijing 100871 China

Non-recurring-engineering(NRE)and time-to-market play an increasingly important role in the field of IC ***,with the continuous development of IC manufacturing technology,it is necessary to propose a novel design methodology to shorten design cycle and enhance design *** this paper,operator design methodology(ODM)is presented and an H.2.4 encoder is implemented as a *** to the flow of ODM,the register transfer level(RTL)design of H.2.4 encoder has been accomplished with 15 man-months,which is lower than the average 19 man-months in the field of traditional application specific integrated circuit(ASIC)***,with the advantage of operator design library,the design has a comparable performance with other ASIC *** obtained design can support a real-time video encoding of 72.p at 60 frames per second or 1080p at 30 frames per second,working at 167 MHz with SMIC 0.13 μm CMOS *** results provide good evidence for the practicability and efficiency of ODM.

关键词： operator design methodology H.2.4 encoder integrated circuit hardware

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CaO-超细高岭土复合固硫剂固硫动力学研究

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燃料化学学报 2004年第4期32卷 424-428页

作者：刘金权武增华王立新清华大学化学系深圳市宝安科技局深圳518101

利用高岭土的加工产品超细高岭土,制备了CaO 超细高岭土复合固硫剂,用热分析法研究其固硫性能和特征,并用等效粒子模型对该固硫剂固硫反应的动力学过程进行模拟和计算,得到了固硫反应的动力学参数。研究表明,CaO 超细高岭土复合固硫剂... 详细信息

利用高岭土的加工产品超细高岭土,制备了CaO 超细高岭土复合固硫剂,用热分析法研究其固硫性能和特征,并用等效粒子模型对该固硫剂固硫反应的动力学过程进行模拟和计算,得到了固硫反应的动力学参数。研究表明,CaO 超细高岭土复合固硫剂有着较好的固硫率,特别是高于1000℃时在固硫反应后期的产物层扩散控制阶段呈现很好的固硫率增长,1009℃下固硫率较CaO提高达2.%。

关键词：复合固硫剂 CaO-超细高岭土固硫反应动力学

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Identification of secondary organic aerosols based on aerosol mass spectrometry

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中国科学：化学英文版 2010年第12期53卷 2593-2599页

作者： HUANG XiaoFeng 1,ZHAO QianBiao 1,2.HE LingYan 1,HU Min 2.BIAN QiJing 3,XUE Lian 1 & ZHANG YuanHang 2.1 Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy,Peking university shenzhen {2. School,shenzhen 518055,china 2.State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking university,Beijing 100871,china 3 Division of Environment,Hong Kong university of Science & Technology,Hong Kong,china 1. Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School Shenzhen 518055 China2. State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China3. Division of Environment Hong Kong University of Science & Technology Hong Kong China

Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so *** to the complex chemical composition of organic aerosols,the identification of SOA has been a hotspot and difficult issue in the field of aerosol *** study attempts to quantitatively identify SOA in winter of shenzhen based on positive matrix factorization (PMF) *** sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer *** showed that in the winter of shenzhen the average SOA concentration was 9.41±6.33 g/m 3,accounting for 39.9±2..8% of the total organic *** with primary organic aerosol (POA),the SOA concentrations had no large variation,suggestive of characteristics of regional secondary *** ratio of SOA/BC had pronounced diurnal variation,similar to that of O x (O3+NO2.,indicating SOA formation was significantly controlled by activity of photochemistry in the *** most effective period for SOA formation was from 9 am～3 pm since the SOA/BC ratio increased by 12.% during this *** study provides a new technical method and a new idea for SOA investigation.

关键词： secondary organic aerosol aerosol mass spectrometry positive matrix factorization (PMF)

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Polarization filtering technique based on oblique projections

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Science china(Information Sciences) 2010年第5期53卷 1056-1066页

作者： ZHANG QinYu ? , CAO Bin, WANG Jian & ZHANG NaiTong Communication Engineering Research Center, shenzhen graduate School, Harbin Institute of Technology,{2., china 1. Communication Engineering Research Center Shenzhen Graduate School Harbin Institute of Technology Shenzhen 518055 China

Based on the theory of polarization filtering and the merits of interference suppressions when adopting oblique projections, a novel polarization filtering algorithm is proposed in this paper. The proposed method can effectively separate the target signal and interference without additional transformation and compensation processing, and the target does not suffer distortions after separation. The suggested scheme is still valid when the target and interference hold the same polarized angle but different phase difference in polarized angle. We extend the application to the scope of known target polarization but unknown interference polarization, finding that the interference is restrained and the amplitude/phase of the target are both totally kept. Theoretic analysis and mathematical deduction show that the proposed scheme is a valid and simple implementation. Simulation results also demonstrate that the suggested method can obtain better filtering performance than the conventional polarization filtering (CPF) and the null-phase-shift polarization filtering (NPSPF). It is proved that the proposed OPPF is an extension to the CPF and the NPSPF, and it develops the theory of polarization filtering effectively.

关键词： oblique projection polarization filtering polarization oblique projection operators signal separation interference suppression

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ON THE GENERALIZED INVERSE NEVILLE-TYPE MATRIX-VALUED RATIONAL INTERPOLANTS

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Journal of Computational Mathematics 2003年第2期21卷 157-166页

作者： Zhibing Chen9+(Department of Mathematics, Normal College, shenzhen university, shenzhen 518060, china) Department of Mathematics Normal College Shenzhen University Shenzhen 518060

A new kind of matrix-valued rational interpolants is recursively established by means of generalized Samelson inverse for matrices, with scalar numerator and matrix-valued denominator. In this respect, it is essentially different from that of the previous works [7, 9], where the matrix-valued rational interpolants is in Thiele-type continued fraction form with matrix-valued numerator and scalar denominator. For both univariate and bivariate cases, sufficient conditions for existence, characterisation and uniqueness in some sense are proved respectively, and an error formula for the univariate interpolating function is also given. The results obtained in this paper are illustrated with some numerical examples.

关键词： Generalized inverse for matrices Neville-type Rational interpolants.

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Variation properties of ionospheric eclipse factor and ionospheric influence factor

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Progress in Natural Science:Materials International 2005年第6期15卷 573-576页

作者： ZHAO Chunmei 1,2.*, YUAN Yunbin1, OU Jikun1 and CHEN Jinping3(1. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, china 2. graduate School of Chinese Academy of Sciences, Beijing 100039, china 3. Department of Precision Instrument and Mechanology, tsinghua university, Beijing 100084, china) Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China graduate School of Chinese Academy of Sciences Beijing 100039 China Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The concepts and calculation methods of ionospheric eclipse factor (IEF) and ionospheric influence factor (IFF) are further illustrated. The temporal and spacial variation properties of IEF and IFF are studied, which shows that the properties are influenced by the geographic position and season. The possibility of improving the precision of using GPS data to determine ionospheric delay based on the above variation properties is also analysed.

关键词： GPS ionospheric eclipse factor ionospheric influence factor

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H2./H∞ control of networked control system with random time delays

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Science china(Information Sciences) 2011年第12期54卷 2635-2650页

作者： QIU Li 1,2., XU BuGong 1 & LI ShanBin 1 1 College of Automation Science and Engineering, South china university of Technology, Guangzhou 510640, china 2.College of Mechatronics and Control Engineering, shenzhen university, shenzhen 518060, china 1. College of Automation Science and Engineering South China University of Technology Guangzhou 510640 China2. College of Mechatronics and Control Engineering Shenzhen University Shenzhen 518060 China

This paper investigates the H 2./H ∞ control problem for a class of discrete-time networked control systems with random communication time delays. Both sensor-to-controller (S-C) and controller-to-actuator (C-A) random network-induced delays are considered. Two independent Markov chains are used to model the S-C and C-A random delays. The resulting closed-loop system is a jump linear time-delay system induced by two Markov chains. Sufficient conditions for existence of H 2./H ∞ controller are established by free-weighting matrix and stochastic Lyapunov functions. A simulation example illustrates the effectiveness of the proposed method.

关键词： H 2./H ∞ control networked control systems Markov chains random time delays

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