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PUTONGHUA, THE CHINESE STANDARD NATIONAL COMMON SPEECH, AND THE beijing VERNACULAR

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世界汉语教学 1992年第1期6卷 63-66页

作者： Hu Mingyang, People’s university of china

*** is Putonghua? Putonghua is the official term for the Chinese standard national common speech *** 1949 it was Guoyü(the national language),which is still in use in Taiwanand in some other ***,from Portuguese manda... 详细信息

关键词：汉语教学世界责任编辑

A HIGH ACCURACY AND FAST AUTOMATIC PROCESSING METHOD OF YOUNG′S FRINGE PATTERN IN PIV

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Chinese Journal of Aeronautics 1994年第1期7卷 17-22页

作者： Ma Guangyun, Shen Gongxin(Institute of Fluid Mechanics.beijing university,of Aeronautics and Astronautic.beijing,{3.,100083.

AbstractA new method for automatic processing of Young′s fringe pattern obtained from PIVphotograph is presented. The fringe orientation is determined by searching for the maxi-mum of the function W(a) which is constructed from 2-D Young′s fringe intensity *** influence of diffraction halo is removed by a simulated function constructedwith normal function. The fringe spacing is derived by calculating iD Fourier *** of 1-D fringe intensity distribution.A high measurement accuracy could be ob-tained (the measurement errors of fringe orientation and spacing are less than 0.5°and 1% respectively). Furthcrmore,only a less amount of computation is required.

关键词： FAST AUTOMATIC AND ACCURACY PIV

Viscosity solution to nonlinear H_∞ control

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Chinese Science Bulletin 1997年第11期42卷 890-894页

作者： HONG Yiguang, YUNG Siupang, MEI Shengwei and QIN Huashu1. Institute of Systems Science, Chinese Academy of Sciences, beijing 100080, china 2. Department of Mathematics, Hong Kong university, Hong Kong, china Institute of Systems Science Chinese Academy of Scirnces Beijing China Department of Mathematics How Kong University Hong Kong China

where the state variable x∈R^n,the output z∈R^k,the control variable u∈U R^m,and thedisturbance w∈W R^l.U and W are compact.F,Z are C^1 mappings defined in a neigh-

关键词： nonlinear H∞ control viscosity solution disturbance attenuation.

MEASUREMENT OF K_(IC)OF MEDIAN OR LOW STRENGTH STEEL USING ROUND BARS WITH CIRCUMFERENCIAL CRACK

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Acta Metallurgica Sinica(English Letters) 1989年第3期2卷 201-207页

作者： LIU Zaihua Huazhong university of Science and Technology,Wuhan,china ZHAO Dongli Bureau of Complete Sets of Equipment,State Machinery Commission,beijing,china Dept.of Mechanics,Huazhong university of Science and Technology,Yujiashan,Wuhan,china

The size effect of tension round bars with circumferential crack was described and used to measure the plane-strain fracture toughness K_(1c) of median or low strength *** size of cylindrical specimen required for K_(1c) measurement is much smaller than that of standard *** J-integral values of the cylindrical sqecimens were calculated to characterize the size *** finite element calculution and fracture morphology analysis have been conducted to eyplain the fact that smaller cylindrical specimen could be used to measure K_(1c) of median or low strength steel.

关键词： median or low strength steel fracture touglmess round bar specimen

IN SITU TEM STUDY ON THE R-PHASE TRANSFORMATION IN TiNi ALLOY

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Acta Metallurgica Sinica(English Letters) 1996年第3期9卷 157-163页

作者： CHEN Qing WU Xingfang and C. J. Humphreys(Department of Materials Physics, university of Science and Technology beijing, beijing 100083. {3.)(Department of Materials Science and Metallurgy, university of Cambridge, Cambridge CBZ 3.Z, U. K.)

The R-phase transformation process in selected TiNi alloys has been studied in great detail by using in situ TEM technique. The R-phase transformation was found to be a reversible thermoelastic displacive transformation with a nucleation and growth process. The R-phase nucleates at the precipitate/matrix interface in aged specimens and grows by moving the coherent R/matrix interfaces. The stress field of Ti3.i4 precipitates plays a much more important role in the formation of the R-phase than dislocations in aged TiNi alloy. The microstructure of the R-phase has also been studied.

关键词： R-phase transformation TiNi alloy in situ TEM

A NOTE ON SINGULAR INTEGRAL OPERATORS

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Analysis in Theory and Applications 1996年第2期12卷 54-59页

作者： Hu Guoen (beijing Normal university,china) 1. Department of Mathematics Beijing Normal University 1000875 Beijing P. R. C.

In this paper,we study the Lp boundedness for the singular integral operators of ***-ferman when the kernel satisfies certain size *** also consider the corresponding maximal singular integral operators.

关键词： singular integral

Efficient degradation of dye pollutants using dioxygen mediated by iron(Ⅱ) 2,2′-bipyridine loaded layered clay catalyst under visible irradiation

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Science china Chemistry 2006年第5期49卷 407-410页

作者： CHENG Mingming1,SUN Zhenying1,2,MA Wanhong1,CHEN Chuncheng1,ZHAO Jincai1 & WANG Zhengping2 1. laboratory of Photochemistry,Center for Molecular Science,Institute of Chemistry,Chinese Academy of Sciences,beijing 100080,china 2. Department of Chemical Engineering,Harbin Engineering {3.,Harbin 150001,china 1. laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. Department of Chemical Engineering Harbin Engineering University Harbin 150001 China

The organic-inorganic layered solid catalyst Fe(bpy)_3.(2+)-laponite was ableto photode-grade Rhodamine B (RhB) by activation of dioxygen under visible irradiation (λ > 420nm), while the homogeneous aqueous solution Fe(bpy)_3.(2+) showed no photoactivity. The catalystcould be repeatedly used and retained its reactivity. The hybrid catalyst could be separated fromthe suspension by centrifugation or sedimentation. The TOC removal yield of RhB was *** oxygen species (ROS) formed during degradation was detected by EPR. A possible mechanismwas proposed on the basis of the experimental results.

关键词： laponite, Rhodamine B, molecular oxygen, visible light.

Oil accumulation related to migration of source kitchens in the Lukeqin structural belt, Turpan-Hami Basin, china

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Petroleum Science 2010年第3期7卷 355-361页

作者： Liu Bo Huang Zhilong Tu Xiaoxian Sang Tingyi Chen Xuan State Key laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Petrochina Turpan-Hami Oilfield Company Hami Xinjiang 839009 China

The Lukeqin structural belt is the main heavy oil accumulation zone in the Turpan-Hami Basin. The recent discovery of light oil in the Triassic indicates that there may be multiple source kitchens contributing to the oil accumulation. According to oil geochemical analysis and oil-source correlation, the oil in deep and shallow reservoirs of the Lukeqin Oilfield presents different physical and saturated hydrocarbon mass spectrum characteristics. The Triassic heavy oil is from the northern Upper Permian lacustrine source rocks, and the light oil represented by the Yudong-9 Well is from the northwestern Lower Jurassic coal-measure source rocks. The timing of oil charging was determined by K/Ar isotope dating, reservoir fluid inclusion analysis and the evolution history of different source rocks. In summary, the accumulation process consists of two stages. From the end of Triassic to early Jurassic, the northern Permian source kitchen generated a considerable amount of oil, which was finally degraded to heavy oil, migrated to the south and then accumulated. The northwestern Jurassic coal-measure source kitchen began to generate oil at the end of Cretaceous, while the northern source kitchen could only generate a little hydrocarbon. The heavy oil and the light oil have different source rock locations, migration directions and accumulation times. The migration of hydrocarbon source kitchens affects the distribution of heavy oil and light oil reservoirs at the present time.

关键词： Source kitchen light oil oil-source correlation timing of oil charging Turpan-Hami Basin

A Fuzzy Logic-Based Framework for Route Choice in Vehicle Navigation Systems

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Systems Science and Systems Engineering 2000年第4期10卷 467-474页

作者： YANG Qun,\ ZHAO Ya\|nanITS research center, Northern Jiaotong university, beijing 100044, china

Vehicle Navigation Systems (VNS) is an important component of Intelligent Transportation Systems (ITS). These Systems are designed to assist drivers in making pre trip and enroute travel choice decisions, and typically, they must provide route choice, route guidance and other related services. Although there have been a lot of existed systems in the market, and most of them used lots of contemporary technologies, they are believed short of ″true intelligence″, because they paid little attention to the subjective issues in driver′s route choice behavior, such as travel objectives and personal preferences, etc. \;However, the VNS is designed for its users, and the successful implementation of VNS is largely dependent on the driver′s acceptance. If the driver feels that the VNS can′t give him (her) a satisfactory choice, he (she) will not use it, then, the marketing value of VNS will decline. And on the whole, the transport benefit that is mainly gained by the wide use of ITS will lost. \;Supported by the research project of ″beijing Intelligent Urban Transportation Systems″, this paper presents a conceptual model to deal with this problem. We first defined the driver′s objective as a linguistic statement that has a set of attributes. These attributes are then treated as the fuzzy sets on the universal of all the existed routes. By determining each attribute′s membership function and assign driver dependent perception to these attributes, we can change the multi criteria route choice problem into a fuzzy logic based decision making problem. Then, to meet the demands of dynamic real time route selection, we use a limited routes set for choice and can swiftly get a satisfactory solution that we think is the driver′s actually needs.

关键词： vehicle navigation systems intelligent transportation systems fuzzy logic