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On stability of elastic domain during isothermal solid-solid phase transformationin a tube configuration

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Acta Mechanica Sinica 2012年第3期28卷 683-694页

作者： Liang Dong qing-ping Sun Department of Mechanical Engineering The Hong Kong University of Science and TechnologyClear Water Bay Hong Kong China

Under isothermal quasi-static stretching the phase transition of a superelastic NiTi tube involves the formation （during loading） and vanishing （in unloading） of a high strain （martensite） domain. The two events are accompanied by a rapid stress drop/rise due to the formation/vanishing of do- main fronts. From a thermodynamic point of view, both are instability phenomena that occur once the system reaches its critical state. This paper investigates the stability of a shrink- ing cylindrical domain in a tube configuration during unload- ing. The energetics and thermodynamic driving force of the cylindrical domain are quantified by using an elastic inclu- sion model. It is demonstrated that the two domain fronts ex- hibit strong interaction when they come close to each other, which brings a peak in the total energy and a sign change in the thermodynamic driving force. It is proved that such domain front interaction plays an important role in control- ling the stability of the domain and in the occurrence of stress jumps during domain vanishing. It is also shown that the pro- cess is governed by two nondimensional length scales （the normalized tube length and normalized wall-thickness） and that the length scale dependence of the critical domain length and stress jump for the domain vanishing can be quantified by the elastic inclusion model.

关键词： Cylindrical elastic domain Stability of domain Domain front Critical domain length Stress jump ~ Ther-modynamic driving force

Fully Quantized Theory of Six-Wave Mixing with Matter Waves

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Communications in Theoretical Physics 2008年第2期49卷 477-478页

作者： ZHOU qing ping Department of Information and Automatization Jishou University Zhangjiajie 427000 China Department of Physics Hunan Normal University Changsha 410081 China

We show that Wu-Yang theory of fully quantized four-wave mixing can be generalized to the six-wave mixing and derive the analytical solution of the coupled equations describing the quantum dynamics of six-wave mixing.

关键词： multiwave mixing fully quantized theory matter waves

Mechanical analysis of phase transition experiments of the bacterial flagellar filament

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Acta Mechanica Sinica 2010年第5期26卷 777-785页

作者： Xiao-Ling Wang qing-ping Sun Department of Mechanical Engineering University of Scienceand Technology Beijing 100083 Beijing China Department of Mechanical Engineering The Hong KongUniversity of Science and Technology Hong Kong China

Bacterial flagellar filaments can undergo a polymorphic phase transition in both vitro and vivo environments. Each bacterial flagellar filament has 12 different helical forms which are macroscopically represented by different pitch lengths and helix radii. For external mechanical force induced filament phase transitions, there is so far only one experiment performed by Hotani in 1982, who showed a very beautiful cyclic phase transition phenomenon in his experiment on isolated flagellar filaments. In the present paper, we give a detailed mechanical analysis on Hotani＇s experiments. Through theoretical computations, we obtained a phase transition rule based on the phase transition mechanism. The theoretical analysis provides a foundation facilitating the establishment of phase transition theory for bacterial flagellar filaments.

关键词： The polymorphic phase transition Bacterial flagellar filament. Pitch lengths The cyclic phase transition

Controllable Persistent Atom Current of Bose-Einstein Condensates in an Optical Lattice Ring

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Communications in Theoretical Physics 2005年第5期43卷 819-822页

作者： ZHENGGong-ping LIANGJiu-qing InstituteofTheoreticalPhysicsandDepartmentofPhysics ShanxiUniversityTaiyuan030006China

In this paper the macroscopic quantum state of Bose-Einstein condensates in optical lattices is studied by solving the periodic Gross-Pitaevskii equation in one-dimensional geometry. It is shown that an exact solution seen to be a travelling wave of excited macroscopic quantum states resultes in a persistent atom current, which can be controlled by adjusting of the barrier height of the optical periodic potential. A critical condition to generate the travelling wave is demonstrated and we moreover propose a practical experiment to realize the persistent atom current in a toroidal atom waveguide.

关键词： Bose-Einstein condensate persistent atom current

Parallel programming characteristics of a DSP-based parallel system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1669-1675页

作者： GAO Shu GUO qing-ping School of Computer Science Wuhan University of Technology Wuhan 430063 China

This paper firstly introduces the structure and working principle of DSP-based parallel system, parallel accelerating board and SHARC DSP chip. Then it pays attention to investigating the system’s programming characteristics, especially the mode of communication, discussing how to design parallel algorithms and presenting a domain-decomposition-based complete multi-grid parallel algorithm with virtual boundary forecast (VBF) to solve a lot of large-scale and complicated heat problems. In the end, Mandelbrot Set and a non-linear heat transfer equation of ceramic/metal composite material are taken as examples to illustrate the implementation of the proposed algorithm. The results showed that the solutions are highly efficient and have linear speedup.

关键词： Parallel algorithm Multi-grid Domain decomposition Virtual boundary forecast (VBF) DSP-based parallel system

Evaluation of tourism climate comfort in the Grand Shangri-La region

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Journal of Mountain Science 2019年第6期16卷 1452-1469页

作者： CHENG qing-ping ZHONG Fang-lei Northwest Institute of Eco-Environmental and Resources Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China School of Economics Lanzhou UniversityLanzhou 730000China

The Grand Shangri-La(GSL) region has strong international tourist appeal. GSL has considerable international eco-tourist potential as well as being attractive for leisure, vacation, health, explorative, and scientific research activities in addition to high-end tourism experiences. These factors could promote the development of its regional tourism. GSL has been identified as a key area for tourism development in China. In this study, we investigated tourism climate conditions in GSL from 1980 to 2016 using a tourism climate index(TCI). We found that through global warming, the number of annual and monthly good-weather days, as assessed with the TCI, showed an increase over most of GSL;that trend was especially true for very good, excellent, and ideal days. The optimal travel period was May–October. We obtained the same result using cluster heat maps, in which we categorized 31 studied meteorological stations into eight types. However, heavy rainfall tended to occur during that optimal period, and it was concentrated at certain times. The annual total number of comfortable days greater than 300 was mainly located in southern GSL. We observed significant correlations between monthly and annual excellent and ideal days with latitude and elevation;in particular, we identified a significant nonlinear correlation between excellent(and ideal) days and elevation.

关键词： Grand Shangri-La region Evaluation Tourism climate comfort Cluster heat maps Temperature Precipitation

New Results on Common Properties of Bounded Linear Operators RS and SR

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Acta Mathematica Sinica,English Series 2013年第10期29卷 1871-1884页

作者： qing ping ZENG Huai Jie ZHONG School of Mathematics and Computer Science Fujian Normal University

Let X, Y be Banach spaces, R ： X → Y emd S ： Y →X be bounded linear operators. When λ ≠ 0, we investigate common properties of λ i - SR and ,λ I - RS. This work should be viewed as a continuation of researches of Barnes and Lin et al.. We also apply these results obtained to B-Fredholm theory, extensions and Aluthge transforms.

关键词： Regularity spectrum extension aluthge transform

The simulation of gas production from oceanic gas hydrate reservoir by the combination of ocean surface warm water flooding with depressurization

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Acta Mechanica Sinica 2012年第5期28卷 1287-1295页

作者： Hao Yang Yu-Hu Bai qing-ping Li Xinxing Heavy Industries Corporation Limited China National Offshore Oil Corporation Research Institute

A new method is proposed to produce gas from oceanic gas hydrate reservoir by combining the ocean surface warm water flooding with depressurization which can efficiently utilize the synthetic effects of thermal, salt and depressurization on gas hydrate dissociation. The method has the advantage of high efficiency, low cost and enhanced safety. Based on the proposed conceptual method, the physical and mathematical models are established, in which the effects of the flow of multiphase fluid, the kinetic process of hydrate dissociation, the endothermic process of hydrate dissociation, ice-water phase equilibrium, salt inhibition, dispersion, convection and conduction on the hydrate disso- ciation and gas and water production are considered. The gas and water rates, formation pressure for the combination method are compared with that of the single depressurization, which is referred to the method in which only depres- surization is used. The results show that the combination method can remedy the deficiency of individual producing methods. It has the advantage of longer stable period of high gas rate than the single depressurization. It can also reduce the geologic hazard caused by the formation defor- mation due to the maintaining of the formation pressure by injected ocean warm water.

关键词： Gas hydrate reservoir Ocean surface warmwater flooding Depressurization Numerical simulation Combination exploitation

Analytical Solution of Weak-Coupling Periodically Driven Two-Level System

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Communications in Theoretical Physics 2008年第4期49卷 1025-1028页

作者： ZHOU qing-ping FANG Mao-Fa College of Information Management and Engineering Jishou University Zhangjiajie 427000 China College of Physics and Information Science Hunan Normal University Changsha 410081 China

We present an approximate analytical solution to periodically driven two-level system in the weak-coupling regime. The analytical solution is in good agreement with the exact numerical solution in resonance and near r... 详细信息

关键词： periodically driven two-level systems analytical solution weak-coupling regime