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The Design of Lens Imaging System byMeans of Fractional Fourier Transform

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Chinese Journal of Lasers 2002年第2期11卷 27-32页

作者： CHeN Jiannong XU Qiang (Department of Physics, Yantai Teachers’ University, Yantai 264025, China)D.R.Selviah(Department of electronic and electrical engineering, University College london, Torrington Place, london wc1e 7je, UK) Department of Physics Yantai Teachers' University Yantai 264025 Department of electronic and electrical engineering University College London Torrington Place 英国 London WC1E 7JE

The relation between the 2nd fractional Fourier transform and the imaging process of an optical system is discussed. By changing the coordinate scales of the input plane in respect to the magnification of the optical imaging system, the fractional Fourier transform can be a powerful tool in designing specific imaging system. The Gaussian imaging formula of single lens is obtained by using the tool. Finally the procedures are generalized for designing a double-lens imaging system through an example.

关键词： lens imaging system fractional Fourier transform Gaussian imaging formula

RADIATION AND DIFFRACTION OF WATeR WAVeS BY A SUBMeRGeD CIRCULAR CYLINDeR AT FORWARD SPeeD

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Journal of Hydrodynamics 1993年第4期5卷 85-96页

作者： G.X.Wu Department of Mechanical engineering,University College london,Torrington Place,london wc1e,7je,U.K.

The wave radiation and diffraction by a submerged circular cylinder in deep water is analysed by the multipole expansion *** theory is based on the inviscid and linearized potential flow.

关键词： flow water wave circular cylinder

The sloshing of stratified liquid in a two-dimensional rectangular tank

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Science China(Physics,Mechanics & Astronomy) 2011年第1期54卷 2-9页

作者： WU GuoXiong1,2 1 State Key Laboratory of Ocean engineering,College of Naval Architecture,Ocean and Civil engineering,Shanghai Jiao Tong University,Shanghai 200240,China 2 Department of Mechanical engineering,University College london,Torrington Place,london wc1e 7je,UK 1. State Key Laboratory of Ocean engineering College of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 20024 China2. Department of Mechanical Engineering University College Londo Torrington Place London WC1E 7JE UK

The sloshing of inviscid liquid of stratified density in a rectangular tank is *** the flow is no longer irrotional,the governing equation is found to be quite different from the Laplace equation used for the liquid of constant *** particular it contains terms of mixed temporal and spatial *** problem is solved based on the variable separation method and Laplace transform for the constant Vaisala-Brunt *** is found that the stratification of density may have small effects on those natural frequencies associated with the constant density,but many new natural frequencies have appeared as a result of its effect.

关键词： sloshing density stratification resonance rectangular tank

Dual-turbo receiver architecture for turbo coded MIMO-OFDM systems

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Science China(Information Sciences) 2012年第2期55卷 384-395页

作者： WANG WenJin1,GAO XiQi1,WU XiaoFu2,YOU XiaoHu1,ZHAO ChunMing1 & WONG Kai-Kit3 1National Communication Research Laboratory,Southeast University,Nanjing 210096,China 2Nanjing Institute of Communications engineering,Nanjing 210007,China 3Department of electrical and electronic engineering,University College london london wc1e 7je,UK 1. National Communication Research Laboratory Southeast University Nanjing 210096 China2. Nanjing Institute of Communications Engineering Nanjing 210007 China3. Department of Electrical and Electronic Engineering University College London London WC1E 7JE UK

This paper presents a novel architecture of iterative receivers with two layers of iterations for turbo coded multiple-input and multiple-output orthogonal frequency-division multiplexing(MIMO-OFDM)systems,where soft messages are passed not only between the MIMO detector and the turbo decoder,but also between the two component decoders within the turbo *** first derive the factor graph representation of a turbo coded system as a basic building block for developing the iterative ***,a new soft message passing schedule over the factor graph is proposed,resulting in the proposed dual-turbo receiver architecture(DTRA).In DTRA,the MIMO detector and the turbo decoder work concurrently,and the soft messages for both layers of iterations are updated instantaneously,instead of the block-based exchange of soft messages in the conventional iterative *** so doing,the processing latency can be greatly reduced while low computational complexity can be achieved.

关键词： MIMO-OFDM iterative detection and decoding turbo codes

HIGH-INTeNSITY SOURCeS OF UV AND VUV eXCIMeR RADIATION FOR RAPID OXIDATION OF SILICON

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HIGH-INTENSITY SOURCES OF UV AND VUV EXCIMER RADIATION FOR R...

DePOSITIONAL SeQUeNCeS AROUND J/K BOUNDARY IN THe QOMOLONGMA AReA, SOUTH TIBeT

第8届国际材联电子材料国际研讨会

作者： Q. Fang Jun-Ying Zhang Ian W Boyd Dept. of electronic & electrical eng. Univ. College london Torrington Place london wc1e 7je United Kingdom UK Institute of Solid State Physics Chinese Academy of Science Hefei China. Structure Research Laboratory University of Science and Technology of China Hefei 230026 China.

＜正＞ In previous work, we have reported that photo-oxidation of silicon and silicon germanium has been investigated by using ultraviolet （UV） and vacuum ultraviolet （VUV） radiation generated by decaying excimer complexes. Here the principles and oxidation mechanisms on silicon surface by the new generation of UV and VUV radiation and effect of the process parameters are discussed. The photo-oxidation rate of silicon has been found that that depends upon various factors such as wavelength, power density, and exposure-time

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来源： cnki会议评论

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地学前缘 2000年第S1期7卷 21-22页

作者： Shi Xiaoying 1, Nicol Morton 2(1 China University of Geosciences, Beijing 100083,China 2.University of london, london wc1e 7HX,UK)

The uppermost Jurassic to Lower Cretaceous in the Qomolongma (Mt. everest) area were deposited in a strong subsiding setting on passive continental margin. From Tithonian to Valanginian, the area experienced an environment shift from circum\|shelf margin carbonate platform to foreslope, then to deep continental slope [1] . Correspondingly, the sediments change in vertical succession from quartz sandstone, via carbonate grainstone to dark shale intercalated with lithic sandstone of gravity flow. From the Tithonian to Valanginian, eight 3rd\|order sequences have been recognized [1] with clearly delineated sequence boundaries and reasonable biostratigraphic controls of ammonites. From the angle of sequence stratigraphy and sedimentary cycles, the important change happened at ca. 138Ma [2] of the Lower Tithonian (about 120m above Aulacosphinctoides hybonotum zone), where a waved subaerial erosion surface occurs in massive bioclastic grainstone. The boundary at ca. 134 5Ma (latest Tithonian, about 60m below the FAD of \%Berriasella cf. jacobi [3] ) comes to the next. The third one is at ca 132Ma (some 170m above the FAD of Berriasella cf. jacobi [3] , but about 60m below the FAD of Berriasella cf. grandis [3] ). In terms of sea\|level change, the sequence boundary at 134 5Ma is probably the most distinctive one, above which some 60m gravel\|bearing massive medium\|grained quartz sandstone was laid down and obviously truncates the underlying strata. In the dark shale below the sandstone, abundant in ammonites, such as Virgatosphinctes, Aulacosphinctes, Haplophylloceras and Gymnosphinctes are recorded [3] . The quartz sandstone itself does not bear identifiable fossils. Above the quartz sandstone, the strata mainly consists of dark silty shale up to 180m thick, with an prominent marine transgression at the base. Just above the first flooding surface (FFS), quite a number of ammonites such as \%Berriasella\% cf. \%jacobi, Blanofordiceras, Hymalayaites\% and \%Pseudosubplani

关键词： J/K boundary depositional sequences South Tibet

SeCOND ORDeR TRANSIeNT WAVeS AROUND A VeRTICAL CYLINDeR IN A TANK

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Journal of Hydrodynamics 1995年第4期7卷 72-81页

作者： Q. W. Ma, G. X. Wu(Department of Mechanical engineering University College london Torrington Place london wcIe 7je )

The free surface problem bound by two cylinders is analysed based on the velocity potential theory. An analytical solution in the take domain is obtained up to the second order in the perturbation expansion. The results are compared with those obtainal from the fully nonlinear theory based on a finite element *** is found that the second order solutiongives a fsr better agreement with the fully nonlinear solution.

关键词： velocity potential analytical solution time domain fully nonlinear theory,transient waves vertical cylinder

Antibiotic prescribing patterns for upper respiratory tract infections in rural Western China

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Journal of Pharmaceutical Analysis 2010年第4期22卷 247-251页

作者： Li-Fang Dong1,2,Hong Yan2,Jun-Hong Gao3,Duo-Lao Wang4 1.Shaanxi Center for Disease Control and Prevention,Xi’an 710054,China 2.Teaching & Research Section of epidemiology and Health Statistics,Department of Public Health,Medical School of Xi’an Jiaotong University,Xi’an 710061,China 3.Institute of Health Research,China North Industries Group Corporation,Xi’an 710065,China 4.Department of epidemiology and Population Health,london School of Hygiene and Tropical Medicine,london,wc1e 7HT,UK. Shaanxi Center for Disease Control and Prevention Xi'an 710054 China Department of Public Health Medical School of Xi'An Jiaotong University Xi'an 710061 China Institute of Health Research China North Industries Group Corporation Xi'an 710065 China Department of epidemiology and Population Health London School of Hygiene and Tropical Medicine London WC1E 7HT United Kingdom

Objective To explore the prescribing patterns of outpatients receiving antibiotics for upper respiratory tract infections(URTIs)in rural Western China and to identify the correlation in terms of doctors and patients *** Totally 7 678 prescriptions for URTIs were collected from 680 primary health village clinics of 40 counties across 10 provinces of Western *** outcome variables were used in the analysis:the occurrence of prescribing at least one antibiotic drug for an URTI and the occurrence of prescribing two or more antibiotics for an *** logistic regression models were used to examine the socioeconomic and demographic determinants of the above two outcome *** The percentage of prescribing at least one antibiotic for URTIs was 48.6% while the percentage of prescribing antibiotic combination(two or more antibiotics)was 4.6%.The two measurements of antibiotic utilization differed remarkably among the 10 *** diagnosed with tonsillitis and faucitis had higher odds(OR=8.86 for tonsillitis and OR=4.64 for faucitis)of antibiotic prescription than patients with other diagnosis of *** with tonsillitis and faucitis also had higher odds(OR=3.82 for tonsillitis and OR=2.71 for faucitis)of multiple antibiotic prescription than those with other diagnosis of *** number of drugs per prescription and injection in prescriptions were also significant predictors of antibiotic and multiple antibiotic utilization for *** It is concluded that the percentage of antibiotic prescription for URTIs is higher in rural Western China than in most of other countries with available data and that prescriptions of antibiotics for URTIs are associated with residence regions of patients,URTI diagnosis and background information on drug prescription.

关键词： antibiotics pharmacoepidemiology upper respiratory tract infection rural population

Aerosol retrieval over land by exploiting the synergy of TeRRA and AQUA MODIS DATA

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Science China earth Sciences 2006年第6期49卷 641-649页

作者： TANG Jiakui1, XUe Yong1,2, YU Tong3, GUAN Yanning1, CAI Guoyin1 & HU Yincui1 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, China 2. Department of Computing, london Metropolitan University, 166-220 Holloway Road, london N7 8DB, UK 3. Beijing environmental Monitor Center, Beijing 100044, China 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China 2. Department of Computing London Metropolitan University 166-220 Holloway Road London N7 8DB UK 3. Beijing environmental Monitor Center Beijing 100044 China

Aerosol retrieval over land from satellite remotely sensed data remains internationally a difficult task. By using MODIS data, the Dark Dense Vegetation (DDV) algorithm aerosol distribution and properties retrieval over land has shown excellent competence. However, this algorithm is re-stricted to lower surface reflectance such as water bodies and dense vegetation, which limits its actual application, and is unable to be used for high reflective surface such as over urban areas. In this paper, we introduce a new aerosol retrieval model by exploiting the Synergy of TeRRA and AQUA MODIS data (SYNTAM), which can be used for various ground surfaces, including for high reflective surface. Preliminary validations have been carried out by comparing with AeRONeT measured data, which shows good accuracy and promising potential. Further research work is undergoing.

关键词： aerosol retrieval, aerosol optical thickness, MODIS, TeRRA, AQUA.