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science China(Life sciences) 2009年第9期52卷 847-853页

作者： GAO george F. Key Laboratory of Pathogenic Microbiology and Immunology of CAs (CAsPMI) Institute of Microbiology Chinese Academy of Sciences (CAS) China-Japan Joint Laboratory of Molecular Immunology and Molecular Microbiology Institute of Microbiology Chinese Academy of Sciences Graduate University of Chinese Academy of sciences Beijing Institutes of Life science Chinese Academy of Sciences

Although worldwide concern has been raised since the large-scale outbreak of highly pathogenic avian influenza in wild birds at Qinghai Lake,China in 2005,the factors responsible for the ability to kill waterfowl remain unclear. The why and how questions of the H5N1 virus species-jump into its reservoir host need to be answered. In this report we test the pathogenicity and adaptation of Qinghai Lake (Clade 2.2) isolate to Muscovy ducks for further understanding of this virus. The isolate was highly pathogenic in ducks and retained its high pathogenicity even after 20 generations of passage in ducks. During the process of serial passages,only the Ns gene developed non-synonymous substitutions,which caused two mutations in Ns1 protein (Val23Ala and Leu207Pro) and one in Ns2 (Phe55Leu). These mutations persisted immutably through all subsequent passages and the pathogenicity remained high,implying that highly pathogenic H5N1 virus remains stable in aquatic birds through oral transmission. Although the exact functions of these mutations are not known,our results provide an important foundation for further understanding the characteristics of the Qinghai Lake isolates.

关键词： avian influenza virus H5N1 mutation Ns1/2 serial passages

REGULARITY AND RECURRENCE OF sWITCHING DIFFUsIONs

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Journal of systems science & Complexity 2007年第2期20卷 273-283页

作者： george YIN Chao ZHU Department of Mathematics Wayne State University Detroit Michigan 48202 U.S.A.

This work is concerned with switching diffusion processes, also known as regime-switching diffusions. Our attention focuses on regularity, recurrence, and positive recurrence of the underlying stochastic processes. The main effort is devoted to obtaining easily verifiable conditions for the aforementioned properties. Continuous-state-dependent jump processes are considered. First general criteria on regularity and recurrence using Liapunov functions are obtained. Then we focus on a class of problems, in which both the drift and the diffusion coefficients are ＂linearizable＂ with respect to the continuous state, and suppose that the generator of the jump part of the process can be approximated by a generator of an ergodic Markov chain. sufficient conditions for regularity, recurrence, and positive recurrence are derived, which are linear combination of the averaged coefficients （averaged with respect to the stationary measure of the Markov chain）.

关键词： Recurrence regularity switching diffusion

Hybrid competitive Lotka–Volterra ecosystems with a hidden Markov chain

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Journal of Control and Decision 2014年第1期1卷 51-74页

作者： Ky Tran george Yin Department of Mathematics Wayne State UniversityDetroitMIUSA

This work concerns Lotka–Volterra models that are formulated using stochastic differential equations with *** from the existing formulations,the Markov chain that models random environments is *** such partially observed systems,we use Wonham’s filter to estimate the Markov chain from the observable evolution of the population,and convert the original system to a completely observable *** then show that the positive solution of our model does not explode in finite time with probability *** properties including stochastic boundedness,finite moments,sample path continuity and large-time asymptotic behaviour are also ***,stochastic permanence,extinction and feedback controls are also investigated.

关键词： Lotka-Volterra model hidden Markov chain partially observed system

statistical analysis on the influence of mechanical parameters in the vibration of pylons

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Earthquake Engineering and Engineering Vibration 2023年第1期22卷 263-278页

作者： Georgios I.Dadoulis george D.Manolis Laboratory for Experimental Mechanics Department of Civil EngineeringAristotle UniversityThessaloniki 54124Greece

We present a statistical investigation of the degree of influence that assumptions made in relation to the mechanical parameters of a pylon have on its ground-induced *** study is set up by using as a key kinematic variable the displacement at the top of a reference,a stand-alone pylon with a uniform cross-section and fixity at its ***,statistics are produced using a dimensionless displacement ratio defined between the‘parental’and the‘subsidiary’cases,the latter defined for the pylon(a)resting on compliant soil,(b)having an attached top mass,and(c)being non-uniform with ***,two materials are examined,namely,steel and reinforced concrete(R/C).More specifically,this displacement ratio is independent of the excitation and plays the role of a transfer function between the base and the top of the *** horizontal and vertical motions are considered,and the equations of motion are solved in the frequency *** ensuing statistical analysis is conducted for the following parameter combinations:(a)pylon founded on soft,intermediate,and stiff soil;(b)low,intermediate,and high-mass ratios of the attached mass to the pylon′s mass;(c)a constant and quadratic degree of pylon tapering with *** correlation coefficients are calculated for all the above combinations to arrive at statistical results that establish validity bounds and quantify the degree of influence of each assumption on the pylon′s response.

关键词： pylons statistical analysis spearman coefficients structural vibrations elastic waveguides attached masses soil springs tapering

Modelling the daily reference evapotranspiration in semi-arid region of south India: A case study comparing ANFIs and empirical models

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Information Processing in Agriculture 2021年第1期8卷 173-184页

作者： Ramiro T.Gonzalez del Cerro M.s.P subathra Nallapaneni Manoj Kumar sebastian Verrastro s.Thomas george Departamento de Ingenieria Electronica Facultad Regional Buenos AiresUniversidad Tecnologica NacionalBuenos AiresArgentina Department of Electrical sciences Karunya Institute of Technology and SciencesCoimbatore 641114Tamil NaduIndia school of Energy and Environment City University of Hong KongKowloonHong KongChina sustainable solutionz T NagarChennai-600017Tamil NaduIndia

The estimation of evapotranspiration(ETo)is one of the main tools for the control of crop growth and to make a rational use of water *** estimate this parameter accurately,it is necessary to have a daily measurement of four meteorological variables,these are:temperature,solar radiation,relative humidity and wind *** is not always possible to count on all the variables,that is why there are empirical methods that use a limited number of variables that make an approximate estimate of the ETo *** of these models are applicable to different regions with completely different *** this paper,a study has been carried out to define the model of ETo estimation that best adapts to the semi-arid region in south *** different datasets for the same period from different meteorological stations were *** addition to the empirical methods for estimating ETo,computer models ANFIs(Adaptive Neuro-Fuzzy Inference system)were *** models consist in the future estimation of a certain parameter by using current variables and a history of variables and past *** results of this work show that ANFIs 11 model makes the best estimate with RMsD=0.002 and r=*** RITCHIE method is the most suitable empirical model for this region,which reaches RMsD=0.507 and r=*** addition,ranking of equations is elaborated for both datasets for daily estimates of ***,comparison is made with the results for each case and thus confirm or reject the convenience of one model over the *** achieve this,a series of statistical indicators were used:Index of agreement(d),MAE(Mean absolute error),sEE(standard error of estimate)and RMsD(Root mean square difference).Moreover,a sensitivity analysis was performed in order to compare and show the stability of the best models when an error is introduced within the input *** this case,the empirical models demonstrate a better performance than the ANFIs *** work demonstrates that th

关键词： Evapotranspiration ANFIs ANN semi-arid regions in India Coimbatore RITCHIE method

Magnets, children and the bowel: A dangerous attraction?

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World Journal of Gastroenterology 2012年第38期18卷 5324-5328页

作者： Anil Thomas george sandeep Motiwale Department of Physiology St Mark's Hospital London HA1 3UJ United Kingdom Department of Paediatric surgery Queen's Medical Center University Hospitals Nottingham NG7 2UH United Kingdom

Reports of magnet ingestion are increasing rapidly globally. However, multiple magnet ingestion, the subsequent potential complications and the importance of the early identification and proper management remain both under-recognized and underestimated. Published literature on such cases could possibly represent only the tip of an iceberg with press reports, web blogs and government documents highlighting further occurrence of many more such incidents. The increasing number of complications worldwide being reported secondary to magnet ingestion point not only to an acute lack of awareness about this condition among the medical profession but also among parents and carers who will be in most cases the first to pick up on magnet ingestion. There still seems to be no consensus on the management of magnet ingestion with several algorithms being proposed for management. Prevention of this condition remains a much better option than cure. Proper education and improved awareness among parents and carers and frontline medical staff is key in addressing this rapidly emerging problem. The goal of managing such cases of suspected magnet ingestion should be aimed at reducing delays between ingestion time, diagnosis time and intervention time.

关键词： Multiple magnet ingestion Children Bowel injury Fistulation Necrosis

On similitude law of sub-systems

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Earthquake Engineering and Engineering Vibration 2006年第1期5卷 133-142页

作者： Zach Liang george C.Lee Department of Civil structural and Environmental Engineering University at BuffaloState University of New YorkBuffaloNew YorkUSA Multidisciplinary Center for Earthquake Engineering Research University at BuffaloState University of New YorkBuffaloNew YorkUSA

Based on Buckingham＇s π-Theorem, dimensional analysis has achieved considerable success over the past near-century. Model testing has long been a powerful tool in both scientific studies and engineering applications. However, the prototype objects are becoming more and more complicated nowadays, and many of the prototype systems can contain several sub-systems. The conventional theories on model-prototype similarity and dimensional analysis have only limited application since the π-Theorem itself does not distinguish between the original system and subsystems. This is particularly true in the field of structural dynamics, where the structure is often modeled as a multi-degree-of-freedom system. In this paper, we attempt to show that, if a system can be decoupled into several nontrivial subsystems, then, in each subsystem, the number of π-terms will be reduced and therefore simplify the model testing. On the other hand, if a system cannot be decoupled into subsystems, then using model testing with reduced π-term analysis, both experimentally and theoretically, may introduce severe errors.

关键词： similitude law Buckingham's π-theorem model testing sub-systems

Donaldson＇s Q-operators for symplectic manifolds

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science China Mathematics 2017年第6期60卷 1047-1056页

作者： LU Wen MA Xiaonan MARINEsCU george school of Mathematics and statistics Huazhong University of Science and Technology Wuhan 430074 China Institut de Mathematiques de Jussieu-Paris Rive Gauche UFR de Mathematiques Universite Paris Diderot-Paris 7 Paris 75205 France Mathematisches Institut Univerisitat zu Koln KSln 50939 Germany

We prove an estimate for Donaldson's Q-operator on a prequantized compact symplectic *** estimate is an ingredient in the recent result of Keller and Lejmi(2017) about a symplectic generalization of Donaldson's lower ... 详细信息

关键词： Q-operator quantization symplectic manifold

LAVRENTIEV's REGULARIZATION METHOD FOR NONLINEAR ILL-POsED EQUATIONs IN BANACH sPACEs

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Acta Mathematica scientia 2018年第1期38卷 303-314页

作者： santhosh george C.D.sREEDEEP Department of Mathematical and Computational sciences NIT Karnataka

In this paper, we deal with nonlinear ill-posed problems involving m-accretive mappings in Banach spaces. We consider a derivative and inverse free method for the imple- mentation of Lavrentiev regularization method. Using general Hslder type source condition we obtain an optimal order error estimate. Also we consider the adaptive parameter choice strategy proposed by Pereverzev and schock （2005） for choosing the regularization parameter.

关键词： nonlinear ill-posed problem Banach space Lavrentiev regularization m-accretive mappings adaptive parameter choice strategy

Cognitive Linguistics:What It Means and Where It Is Going

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外国语 2005年第2期28卷 2-22页

作者： george Lakoff University of California Berkeley

In this lecture, to begin with, I would go over some of the history of cognitive linguistics: its development, and where it's going, and what has happened in the almost thirty years that it has been developed.

关键词：认知语言学研究进展发展前景语言学派