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Empirical-Statistical Methodology and Methods for Modeling and Forecasting of Climate Variability of Different Temporal Scales

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Advances in Atmospheric Sciences 2001年第5期18卷 844-863页

作者： Vladimir A. Lobanov State Hydrological institute, A MFONP, St. Petersburg, Russia LASG, institute of Atmospheric physics, Beijing 100029. State Hydrological institute AM FONP St. Petersburg Russia LASG Institute of Atmospheric Physics Beijing China

Main problem of modern climatology is to assess the present as well as future climate change, For this aim two approaches are used: physic-mathematic modeling on the basis of GCMs and palaeoclimatic analogues. The third approach is based on the empirical-statistical methodology and is developed in this paper. This approach allows to decide two main problems: to give a real assessment of climate changes by observed data for climate monitoring and extrapolation of obtained climate tendencies to the nearest future (10-15 years) and give the empirical basis for further development of physic-mathematical models. The basic theory and methodology of empirical-statistic approach have been developed as well as a common model for description of space-time climate variations taking into account the processes of different time scales. The way of decreasing of the present and future uncertainty is suggested as the extraction of long-term climate changes components in the particular time series and spatial generalization of the same climate tendencies in the obtained homogeneous regions. Algorithm and methods for realization of empirical-statistic methodology have been developed along with methods for generalization of intraannual fluctuations, methods for extraction of homogeneous components of different time scales (interannual, decadal, century), methodology and methods for spatial generalization and modeling, methods for extrapolation on the basis of two main kinds of time models: stochastic and deterministic-stochastic. Some applications of developed methodology and methods are given for the longest time series of temperature and precipitation over the world and for spatial generalization over the European area.

关键词： climate change climate variability empirical-statistical approach spatial-temporal modeling inhomogeneous non-stationary

Electron Beam Cladding Surface Modification Technology of Niobium Alloy

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稀有金属材料与工程 2011年第S4期40卷 231-234页

作者： He Jun,Wang Shiwei,Zhang Yonghe Lanzhou institute of physics,Lanzhou 730000,China Lanzhou Inst Phys Lanzhou 730000 Peoples R China

The electron beam cladding (EBC) is a new high-energy surface modification technology developed *** on the analysis of principles and critical technologies in EBC,effect of technological parameters on the microstructure and properties of the cladding layer was *** was pointed out that a rational selection of scanning waveform is greatly significant for EBC ***,the progress had achieved and the problems which need to be resolved were introduced.

关键词： electron beam cladding niobium alloy surface modification

Lie map for the nonlinear transport of continuous intense beams in the axial-symmetric electrostatic fields

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Progress in Natural Science:Materials International 2008年第7期18卷 795-800页

作者： Jianqin L*, Xiaosong Zhao institute of Heavy Ion physics, Peking University, Beijing 100871, China institute of Heavy Ion physics Peking University Beijing 100871 China

Nonlinear transport of intense continuous beam in the axial-symmetric electrostatic fields is analyzed with the Lie algebraic method. The K-V particle distribution is adopted in the analysis. The results obtained can be used in the calculations of the intense continuous beam dynamics in the beam optical systems consisting of drift spaces, electrostatic lenses, and DC electrostatic accelerating tubes. A com- puter code has been designed for practical simulations. To meet the needs of accurate calculation, all the elements are divided into many small segments, the electric fields in each segment are regarded as uniform fields, and the dividing points are treated as thin lenses. Iter- ation procedures are adopted in the code to obtain self-consistent solutions. The code can be used to design low energy dc beam transport systems, electrostatic accelerators, and ion implantation machines.

关键词： Intense continuous beam Lie algebraic analysis Nonlinearity

STABLE NONLINEAR RELAXATIONS IN A MULTIPHASIC Al-Zn ALLOY

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中国有色金属学会会刊：英文版 1993年第2期3卷 58-64页

作者： Zhu,Xianfang institute of Solid State physics,Academia Sinica,Hefei 230031,China

The experiments reveal the characteristics of stable damping in a multiphasic Al-Zn eutectoid alloy:（1）Thewhole damping(Q-1)has the same dependence on measured frequency（f）,i.e.Q-1ocf-n,where n is a parameterand is independent of temperature.（2）In a low-temperature（low-T）and low-strain-amplitude（low-A）region,Q-1=（B/）exp（-nH/kT）,where B is a parameter,H the atomic diffusion activation energy,k Boltzmann′sconstant,and T the absolute temperature.n,Ho（=nH）and H are all independent of A.The damping comesfrom an anelastic motion of the phase-interface.（3）In an intermediate region including a low-Tand a high-A,a middle-T and middle A and a high-T and low-A regions,the equation Q-1=（C/fn）exp（nH/kT）stillholds,but the damping has a normal amplitude effect C,n,and H all vary with A;the damping results from anonlinear relaxation of phase-interface.（4）In a high-T and high-A region,there is no longer a linear relationship between InQ-1 and T-1,whereas the relation Q-1f-n is still satisfied,where n increases as A increases,andthe damping has a normal amplitude effect but one which is weaker than that in the case（3）.The damping maybe attributed to another kind of nonlinear relaxation between phase-interfaces.

关键词： non-linear relaxations Al-Zn alloy damping

New Exact and Explicit Solitary WaveSolutions to a Class of Coupled Nonlinear Equations

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Communications in Nonlinear Science and Numerical Simulation 1998年第3期3卷 189-193页

作者： Xuejun XU and Jiefang ZHANG(institute of Nonlinear physics and Dept. of physics. Zhejiang Normal Univ., Jinhua321004, China) institute of Nonlinear physics and Department of physics Zhejiang Normal University Jinhua 321004 China

New exact and explicit solitary wave solutions are obtained for the couplednonlinear equation by using a simple way of making the ansatz u(x, t) =Asechn ζ+A0with ζ = k(x+wt) +ζ0.

关键词： solitary wave solution ansatz coupled nonlinear equations

A CONCEPT FOR NEXT STEP ADVANCED TOKAMAK FUSION DEVICE

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核聚变与等离子体物理 2002年第2期22卷 73-85页

作者： LI Zheng wu (Southwestern institute of physics, Chengdu 610041) Southwestern institute of physics Chengdu 610041

A concept is introduced for initiating the design study of a special class of tokamak,which has a magnetic confinement configuration intermediate between contemporary advanced tokamak and the recently established spherical torus (ST,also well known by the name "spherical tokamak").The leading design parameter in the present proposal is a dimensionless geometrical parameter, the machine aspect ratio A=R 0/a 0= 2.0,where the parameters a 0 and R 0 denote,respectively,the plasma (equatorial) minor radius and the plasma major *** aim of this choice is to technologically and experimentally go beyond the aspect ratio frontier (R 0/a 0≈2.5) of present day tokamaks and enter a broad unexplored domain existing on the (a 0,R 0) parameter space in current international tokamak database,between the data region already moderately well covered by the advanced conventional tokamaks and the data region planned to be covered by *** minor radius a 0 has been chosen to be the second basic design parameter, and consequently,the plasma major radius R 0 is regarded as a dependent design *** the present concept,a nominal plasma minor radius a 0=1.2m is adopted to be the principal design value,and smaller values of a 0 can be used for auxiliary design purposes,to establish extensive database linkage with existing *** minor radius can also be adjusted by mechanical and/or electromagnetic means to smaller values during experiments,for making suitable data linkages to existing machines with higher aspect ratios and smaller plasma minor *** basic design parameters proposed enable the adaptation of several confinement techniques recently developed by STs,and thereby a specially arranged central bore region inside the envisioned tokamak torus,with retrieved space in the direction of plasma minor radius,will be available for technological adjustments and maneuverings to facilitate implementation of engineering instrumentation and real time

关键词：托卡马克装置等离子体磁约束聚变堆

Cyclic Heating-Annealing and Boltzmann Distribution of Free Energies in a Spin-Glass System

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Communications in Theoretical physics 2007年第7期48卷 179-182页

作者： ZHOU Hai-Jun institute of Theoretical physics,the Chinese Academy of Sciences,Beijing 100080,China institute of Theoretical physics the Chinese Academy of Sciences Beijing 100080 China

Ergodicity of a spin-glass is broken at low temperatures;the system is trapped in one of many ergodicconfigurational *** between different ergodic domains are achievable through a *** this experiment is repeated infinite times,all ergodic configurational domains will be visited with frequencesthat decreasing exponentially with their free *** mean free energy density of a spin-glass system on a randomgraph is calculated based on this free energy Boltzmann distribution in the present work,by means of the cavity approach.

关键词： spin-glass ergodicity-broken cavity method

ON THE COHOMOLOGY OF GENERALIZED RESTRICTED LIE ALGEBRAS

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Chinese Annals of Mathematics,Series B 1998年第4期19卷 421-432页

作者： SHU BIN (institute of Applied Mathematics & physics, Shanghai Maritime University, Shanghai 200135, China.) institute of Applied Mathematics and physics Shanghai Maritime University Shanghai 200135 China

In [21], generalized restricted Lie algebras, defined over a field F of positive characteristic p, were introduced. In this note their cohomology, especially the so-called generalized restricted cohomology is studies. Some reduction properties are obtained. For graded Cartan type Lie algebras the author determines the first Lie-cohomology groups and the first generalized restricted cohomology groups with the coefficients in the highest weight modules from which all irreducible generalized restricted modules are derived.

关键词： Generalized restricted Lie algebras Generalized restricted Cohomology Lie algebras of Cartan type

Simulation on C/A codes and analysis of GPS/pseudolite signals acquisition

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Science China(Technological Sciences) 2009年第5期52卷 1459-1462页

作者： ZHANG Lei Shanghai institute of Technical physics,Chinese Academy of Sciences,Shanghai 200083,China Shanghai institute of Technical physics Chinese Academy of Sciences Shanghai China

The global positioning system(GPS) is an extremely mature technique in the navigation and position-ing ***,there are still some limits in some aspects and for some special ***-cially,the performance of GPS needs to be improved with technological *** a GPS-like ground transmitter,the pseudolite provides a new research direction to achieve high positioning ac-curacy and *** this paper,we describe the core technologies of designing and simulation on the coarse acquisition codes in constructing the pseudolite *** the GPS/pseudolite integration system,the signal PRN 36 of the pseudolite and the GPS satellites signals are acquired in the modified receiver based on the computer software *** is shown that the pseudolite technology is ideally suited to augment the GPS alone and provide greater integrity,availability,and continuity of the navi-gation positioning system,especially for indoor use.

关键词： GPS pseudolite coarse acquisition(C/A) code acquisition