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THE WEIGHTED HERZ-TYPE HARDY SPACES hK_q^(α,p)(ω_1,ω_2.

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Analysis in Theory and Applications 1997年第4期13卷 19-41页

作者： Fan Dashan and Yang Dachun (university of WI~Milwaukee, U. S. A. and beijing Normal university,{3.) 1. Department of Mathematical Sciences University of Wisconsin-Milwaukee P.O. Box 413 53201 Milwaukee WI U.S.A. 2. Department of Mathematics Beijing Normal University 100875 Beijing The People's Republic of China

Let (.the Muckenhoupt class). In this paper, the author introduce the weighted Herz-type Hardy spaces (w2. and present their atomic decomposition. Using the atomic decomposition, the author find out their dual spaces, establish the boundedness on these spaces of the pseudo-differential operators of order zero and show that , the class of C(Rn)-functions with compactly support, is dense in and there is a subsequence, which converges in distrbutional sense to some distribution of , of any bounded sequence in In addition, the author also set up the boundedness of some non-linear quantities in compensated compactness.

关键词： THE WEIGHTED HERZ-TYPE HARDY SPACES hK_q III Math

Risk assessment and validation of flood disaster based on fuzzy mathematics

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Progress in Natural Science:Materials International 2009年第10期19卷 1419-1425页

作者： Weiguo Jiang a,b,Lei Denga,b,Luyao Chenc,Jianjun Wu a,b,Jing Lia,b a Key Laboratory of Environment Change and Natural Disaster,MOE,beijing Normal university,beijing 100875,{3. b Academy of Disaster Reduction and Emergency Management,MOCA&MOE,beijing Normal university,beijing 100875,{3. c Department of Geography,Texas A&M university,College Station,TX 77843.3.47,USA [a]Key Laboratory of Environment Change and Natural Disaster MOE Beijing Normal University Beijing 100875 China [b]Academy of Disaster Reduction and Emergency Management MOCA&MOE Beijing Normal University Beijing 100875 China [c]Department of Geography Texas A&M University College Station TX 77843-3147 USA

Floods often take place around rivers and plains,which indicates a higher risk of flooding in these *** paper adopts fuzzy comprehensive assessment(FCA),simple fuzzy classification(SFC),and the fuzzy similarity method(FSM) to assess flood disaster risk in Kelantan,*** data,such as the flooded area,paddy area,urban area,residential area,and refuges,were overlaid to validate and analyze the accuracy of flood disaster *** results show that(1) 70-75% of flooded areas lie within the higher and high-est risk zones,which shows an effective assessment accuracy;(2. paddy,built-up,and residential areas concentrated in the higher and highest risk zones are more likely to be destroyed by flood disasters;(3. 2.0-2.5 refuges in the higher and highest risk zones account for around 50% of all refuges,which means that more refuges should be built in the higher and highest risk zones to meet the accommodation requirement;(4) three methods proved to be feasible and effective in evaluating flood disaster risk,among which FCA is more suitable for the study area than the two other methods.

关键词： Flood disaster Risk assessment Risk validation Fuzzy mathematics Malaysia

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LR语法分析器的可视化交互式动态仿真

系统仿真学报 2009年第7期21卷 1866-1869页

作者：李虎杨晓津北京航空航天大学计算机学院北京100083 总参第61研究所北京100039

LR分析器及其语法制导的翻译方法是编译原理课程教学中的重要内容,其分析器的内部结构复杂,工作原理很难被学生直观地理解和掌握。描述一个在Windows平台上独立开发的可视化、交互式的LR分析器动态仿真软件工具。该工具的新颖之处在于... 详细信息

LR分析器及其语法制导的翻译方法是编译原理课程教学中的重要内容,其分析器的内部结构复杂,工作原理很难被学生直观地理解和掌握。描述一个在Windows平台上独立开发的可视化、交互式的LR分析器动态仿真软件工具。该工具的新颖之处在于它实现了众多高层概念的可视化,支持LR分析器的单步执行和仿真,并允许为产生式附加断点,特别是允许断点插入在产生式右部的任意文法位置。此工具已应用于编译原理的课程教学,亦可用于开发、编写和调试以YACC为代表的LALR(1)分析器生成系统的输入文法规约。

关键词： LR分析器语法分析器生成器可视化调试断点

Continuity of Higher Order Commutators on Certain Hardy Spaces

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Acta Mathematica Sinica,English Series 2002年第2期18卷 391-404页

作者： DING Yong LU Shan Zhen Department of Mathematics,beijing Normal university,beijing 100875.P.R.{3. E-mail:dingy@*** lusz@***ZHANG Pu Department of Mathematics.Zhejiang university(at Xixi Campus).Hangzhou 3.002.,P.R.{3.,E-mail:zhpjj@2.3.net Department of Mathematics Beijing Normal University Beijing P.R. China Department of Mathematics Zhejiang University (at Xixi Campus) Hangzhou P.R. China

In this *** authors study the continuity properties of higher order commutators generated by the homogeneous fractional integral and BMO functions on certain Hardy spaces,weak Hardy spaces and Herz-type Hardy spaces.

关键词： Fractional integral Homogeneous kernel L^r-Dini condition Hardy space Herz-type Hardy space

Hydraulic design and pre-whirl regulation law of inlet guide vane for centrifugal pump

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Science china(Technological Sciences) 2010年第8期53卷 2142-2151页

作者： TAN Lei ,CAO ShuLiang&GUI ShaoBo State Key Laboratory of Hydroscience and Engineering,Department of Thermal Engineering,Tsinghua university,beijing 100084,{2. 1. State Key Laboratory of Hydroscience and Engineering Department of Thermal Engineering Tsinghua University Beijing 100084 China

A new hydraulic design method of three-dimensional guide vane for centrifugal pump is proposed on the assumption that the fluid at the outlet of guide vane satisfies the uniform velocity moment *** geometry of blade is controlled by the distributed rule of blade angles along the meridional streamline which is described by a fourth-order *** results demonstrate that the designed guide vane can overcome the drawback of two-dimensional guide vane,enlarge the high efficiency scope and improve the hydraulic performance of centrifugal pump on the off-design operation *** comparison with the performance of the centrifugal pump without inlet guide vane,the peak value of efficiency can be enhanced by 2.13. after the three-dimensional guide vane was being *** three-dimensional entire flow field of the centrifugal pump with inlet guide vane is simulated,and the basic principle and mechanism of inlet guide vane pre-whirl regulation are *** validity of design method has been proved.

关键词： centrifugal pump inlet guide vane pre-whirl regulation hydraulic design method experiment numerical simulation

Range-instantaneous Doppler imaging of inverse synthetic aperture sonar

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声学技术 2003年第Z1期22卷 48-51页

作者： XU Jia~(1,2., JIANG Xingzhou~(1), TANG Jingsong~(1) (1. Navy Engineering university, Wuhan 43.03., china 2. Department of Electronic Engineering, {2. 100080, china) Navy Engineering university Wuhan 430033 China Department of Electronic Engineering Beijing 100080 China Navy Engineering university Wuhan 430033 China

Because the existing range-Doppler algorithm in inverse synthetic aperture sonar (ISAS) is based on target model of uniform motion, it may be invalidated for maneuvering targets due to the time-varying changes of both individual scatter′s Doppler and imaging projection plane. To resolve the problem, a new range-instantaneous Doppler imaging method is proposed for imaging maneuvering targets based on time-frequency analysis. The proposed approach is verified using real underwater acoustic data.

关键词： inverse synthetic aperture sonar (ISAS), range-instantaneous Doppler, maneuvering target, time-frequency analysis

ON　THE　CONVERGENCE　OF　CONJUGATE　GRADIENT　METHODS INVARIANT TO　NONLINEAR　SCALING

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Systems Science and Mathematical Sciences 1996年第2期9卷 128-133页

作者： DENG Naiyang LI Zhengfeng (Division of Basic Science, beijing Agricultural Engineering university, beijing 100083.{3.) 中国农业工程大学基础科学部北京

ＯＮＴＨＥＣＯＮＶＥＲＧＥＮＣＥＯＦＣＯＮＪＵＧＡＴＥＧＲＡＤＩＥＮＴＭＥＴＨＯＤＳＩＮＶＡＲＩＡＮＴＴＯＮＯＮＬＩＮＥＡＲＳＣＡＬＩＮＧＤＥＮＧＮａｉｙａｎｇ；ＬＩＺｈｅｎｇｆｅｎｇ（ＤｉｖｉｓｉｏｎｏｆＢａｓｉｃ... 详细信息

ＯＮＴＨＥＣＯＮＶＥＲＧＥＮＣＥＯＦＣＯＮＪＵＧＡＴＥＧＲＡＤＩＥＮＴＭＥＴＨＯＤＳＩＮＶＡＲＩＡＮＴＴＯＮＯＮＬＩＮＥＡＲＳＣＡＬＩＮＧＤＥＮＧＮａｉｙａｎｇ；ＬＩＺｈｅｎｇｆｅｎｇ（ＤｉｖｉｓｉｏｎｏｆＢａｓｉｃＳｃｉｅｎｃｅ，ＢｅｉｊｉｎｇＡｇ...

关键词： GRAD

Multiple Successions of Soliation Development in Shallow Versus Deep Orogenic Regimes and Their Relationship to Regional Folding

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地学前缘 2009年第S1期16卷 89-90页

作者： Hui Cao State Key Laboratory of Geological Processes and Mineral Resources Institute of Land Resources and High Techniques,china university of Geosciences({2.),{2. 100083.china.

With the realization that rocks with a schistosity parallel to bedding(S0 parallel S1)have undergone lengthy histories of deformation that predate the obvious first deformation(*** et al.,2.03. Sayab,2.06;Yeh,2.07)came recognition that large scale regional folds can form early during this process and be preserved throughout orogenesis(e.g.,Ham & Bell,2.04;Bell & Newman,2.06).This history is lost within the matrix because of reactivational shear

关键词： orogenesis axial planes of folds porphyroblasts foliation intersection/inflection axes(FIAs)

Mesenchymal stem cells derived from human placenta suppress allogeneic umbilical cord blood lymphocyte proliferation

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Cell Research 2005年第7期15卷 539-547页

作者： Peihsien TANG Department of Cell Biology Institute of Basic Medical Sciences Academy of Military Medical Sciences beijing 100850 china

ABSTRACTHuman placenta-derived mononuclear cells (MNC) were isolated by a Percoll density gradient and cultured in mesen-chymal stem cell (MSC) maintenance medium. The homogenous layer of adherent cells exhibited a typical fibroblast-like morphology, a large expansive potential, and cell cycle characteristics including a subset of quiescent cells. In vitrodifferentiation assays showed the tripotential differentiation capacity of these cells toward adipogenic, osteogenic andchondrogenic lineages. Flow cytometry analyses and immunocytochemistry stain showed that placental MSC was ahomogeneous cell population devoid of hematopoietic cells, which uniformly expressed CD2., CD44, CD73. CD105,CD166, laminin, fibronectin and vimentin while being negative for expression of CD3., CD3., CD45 and α-smoothmuscle actin. Most importantly, immuno-phenotypic analyses demonstrated that these cells expressed class I majorhistocompatibility complex (MHC-I), but they did not express MHC-II molecules. Additionally these cells could sup-press umbilical cord blood (UCB) lymphocytes proliferation induced by cellular or nonspecific mitogenic stimuli. Thisstrongly implies that they may have potential application in allograft transplantation. Since placenta and UCB arehomogeneous, the MSC derived from human placenta can be transplanted combined with hematopoietic stem cells(HSC) from UCB to reduce the potential graft -versus-host disease (GVHD) in recipients.

关键词： mesenchymal stem cells human placenta umbilical cord blood immune regulation.