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Infrared spectral evolution of carbon stars

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Research in Astronomy and Astrophysics 2010年第4期10卷 363-382页

作者： Pei-Sheng Chen xiao-hong Yang hong-Guang Shan National Astronomical Observatories /Yunnan Observatory and Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China Department of Physics Chongqing UniversityChongqing 400044China

We collected almost all Highly Processed Data Products （HPDP） of ISO SWS01 spectra for the Galactic visual carbon stars,infrared carbon stars,extreme carbon stars and carbon-rich proto-planetary nebulae （PPNs）.Those infrared spectra are primarily analyzed and *** is shown that either spectral shapes/peaks,or main molecular/dust features are evidenced to change in the sequence of visual carbon stars,infrared carbon stars,extreme carbon stars and carbon-rich ***,in this sequence,continua are gradually changed from blue to red and locations of spectral peaks of continua are also gradually changed from short wavelengths to long *** addition,in this sequence,intensities of main molecular/dust features are also gradually changed from prominent in the short wavelengths to prominent in the long ***,from 2MASS and IRAS photometric data,the sequence is also *** in this paper strongly support the previous suggestion for the evolution sequence of carbon-rich objects in our Galaxy,that is the sequence of visual carbon stars → infrared carbon stars → extreme carbon stars → carbon-rich PPNs.

关键词： infrared:stars - stars:carbon - stars:late type

Development and application of software packages in welding engineering

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Frontiers of Materials Science 2011年第2期5卷 160-167页

作者： Yan-hong WEI xiao-hong ZHAN Zhi-Bo DONG School of Material Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China State Key Laboratory of Advanced Welding Technology Production Harbin Institute of Technology Harbin 150001 China

The weldabiUty of some material is analyzed with simple calculating program in this paper, and weldability testing data are shared through database system. The welding procedures are designed with help of expert systems, and the knowledge is shared among welding engineers. Not only the preparing progress of the welding documents is completed with database systems but also the complex decision on the necessity of the qualification test according to the present procedure qualification records （PQRs） and manufacture codes is made. Moreover, the artificial neural network （ANN） technique is proven to be one of the effective ways to predict mechanical properties of welded joints when there are enough tested data to train the models. Finally, the achievements in modeling microstructure of welded joints are introduced, especially in solid transformation and grain growth in both heat-affected zone （HAZ） and welded molten pool.

关键词： welding software package, finiteelementmethod (FEM), welding procedurequalification, mechanical properties of welded joints expert system, database system

Model Predictive Control for Vapor Compression Cycle of Refrigeration Process

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International Journal of Automation and computing 2018年第6期15卷 707-715页

作者： xiao-hong Yin Shao-Yuan Li Department of Automation Shanghai Jiao Tong University and Key Laboratory of System Control and Information Processing Ministry of Education of China

A model predictive controller based on a novel structure selection criterion for the vapor compression cycle （VCC） of refrigeration process is proposed in this paper. Firstly, those system variables are analyzed which exert significant influences on the system performance. Then the structure selection criterion, a trade-off between computation complexity and model performance, is applied to different model structures, and the results are utilized to determine the optimized model structure for controller design. The controller based on multivariable model predictive control （MPC） strategy is designed, and the optimization problem for the reduced order models is formulated as a constrained minimization problem. The effectiveness of the proposed MPC controller is verified on the experimental rig.

关键词： Vapor compression refrigeration cycle model structure structure selection criterion model reduction model predictive control.

GRB Energies and E_γ-E_(peak) Correlation with the Jet Expanding Laterally at the Sound Speed

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Chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 503-508页

作者： xiao-hong Zhao Jin-Ming Bai National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Graduate School of Chinese Academy of Sciences Beijing 100049

A Gamma-ray burst （GRB） is generally believed to be a jet with a small opening angle, this opening angle is usually derived with the afterglow light curve break time using an analytical method. Here we show that the method is not accurate. Using the set of equations of hydrodynamic evolution with the sideways expansion at the local sound speed derived by previous authors and the observed light curve break times, we numerically derive the initial opening angles. Then the collimation-corrected energies （Eγ） for a sample of GRBs are calculated. They are found to show a wide spread, suggesting that the previously declared clustering by some authors may not exist. Also, the Epeak - Eγ relation, claimed by some other authors （Epeak is the spectral peak energy）, is found still to hold, with a slightly stronger correlation.

关键词： gamma-ray: bursts - methods: numerical - ISM: jets

Characteristics of Gas Exchange, Chlorophyll Fluorescence and Expression of Key Enzymes in Photosynthesis During Leaf Senescence in Rice Plants

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Journal of Integrative Plant Biology 2005年第5期47卷 560-566页

作者： xiao-YanWENG hong-XiaXU De-AnJIANG NationalLaboratoryofPlantPhysiologyandBiochemistry CollegeofLifeSciencesZhejiangUniversityHangzhou310029China

Abstract: Gas exchange, chlorophyll (Chl) fluorescence, photosynthetic pigments, and the expression of Rubisco and Rubisco activase in flag leaves of rice (Oryza sativa L.) from the heading to mature grain stage were investigated. The results showed that the photosynthetic capacity declined after full expansion of flag leaves. The decline of photosynthetic rate (Pn) in two cultivars during natural senescence was accompanied by a decrease in Chl content, as well as in the Rubisco and Rubisco activase contents. The Rubisco and Rubisco activase contents in Zhenong 966 decreased faster than that in Zhenong 952. The Pn diminished without a decrease in intercellular CO2 concentration during the early senescence of flag leaves, indicating that lower photosynthetic capacity is not caused by stomatal limitation but by reduced carboxylation efficiency. During the senescence of flag leaves, the correlation between the change in photosynthetic capacity and the variation in the abundance of Rubisco and Rubisco activase suggested that the decline in Pn of flag leaves could be attributed to the lower level of rbcS and rca transcripts. The PSII and the electron transport rate appeared in the same rate as Pn. However, excitation pressure (1-qP) showed a different pattern and there was an inverse linear correlation between increased excitation pressure and the reduced Rubisco. Therefore, it is likely that the increased excitation pressure resulted from saturation of the electron transport chain, owing to a limitation of the reductant used by the Calvin cycle; in addition, the change in excitation pressure could further mediate the expression of the rbcS and rca genes, resulting in a fast reduction in Rubisco content.

关键词： chlorophyll fluorescence leaf senescence photosynthesis rice (Oryza sativa L.) Rubisco Rubisco activase

Property(ω) and Its Perturbations

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Acta Mathematica Sinica,English Series 2014年第5期30卷 797-804页

作者： Wei Juan SHI xiao hong CAO College of Mathematics and Information Science Shaanxi Normal University

Abstract A Hilbert space operator T is said to have property （ω1） if σα（T）／σaw（T） π00（T）, where σα（T） andσαw（T） denote the approximate point spectrum and the Weyl essential approximate point spectrum of T respectively, and π00（T） ---- {λ∈ iso σ（T）, 0 〈 dim N（T- λI）〈 ∞}. Ifσα（T）／σαw（T） = π00（T）, we say T satisfies property （w）. In this note, we investigate the stability of the property （wi） and the property （w） under compact perturbations, and we characterize those operators for which the property （wi） and the property （w） are stable under compact perturbations.

关键词： Property (ω1) property (ω) compact perturbations

A Non-symmetric Digital Image Secure Communication Scheme Based on Generalized Chaos Synchronization System

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Communications in Theoretical Physics 2005年第6X期44卷 1115-1124页

作者： ZHANG xiao-hong MIN Le-Quan Applied Science School and Information Engineering School 100083 China Information Engineering School Jiangxi University of Science University of Science and Technology Beijing Beijing and Technology Ganzhou 341000 China

Based on a generalized chaos synchronization system and a discrete Sinai map, a non-symmetric true color （RGB） digital image secure communication scheme is proposed. The scheme first changes an ordinary RGB digital image with 8 bits into unrecognizable disorder codes and then transforms the disorder codes into an RGB digital image with 16 bits for transmitting. A receiver uses a non-symmetric key to verify the authentication of the received data origin, and decrypts the ciphertext. The scheme can encrypt and decz：Fpt most formatted digital RGB images recognized by computers, and recover the plaintext almost without any errors. The scheme is suitable to be applied in network image communications. The analysis of the key space, sensitivity of key parameters, and correlation of encrypted images imply that this scheme has sound security.

关键词： generalized chaos synchronization Sinai map image confusion non-symmetric key data origin authentication network communication

Spectral variations of carbon stars based on ISO SWS data

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Research in Astronomy and Astrophysics 2009年第12期9卷 1359-1367页

作者： xiao-hong Yang Pei-Sheng Chen Department of Physics Chongqing University Chongqing 400044 China National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China

We investigate the spectral variations of seven carbon stars in the infrared using ISO SWS spectral data. Continuum variations of those carbon stars show that during the central star pulsations when carbon stars become fainter in the infrared, their ISO SWS spectra become redder and the near-IR temperature （Tnir） decreases. When carbon stars become brighter in the infrared, their ISO SWS spectra become bluer and Tnir increases. Furthermore, it is found that the shorter 1abe wavelength of spectral features, such as the 2.48＋2.58 （C2H2＋HCN＋CO＋C2）, 3.05 （C2H2＋HCN） and 3.90 （C2H2） μm features, is, the better the correlation of their relative integrated fluxes with the fluxes of the continuum is. The changes of the 5.2 （C3）, 11.30 （SIC） and 13.70 （C2H2）μm features do not obviously correlate with the fluxes of the continuum.

关键词： stars: AGB and post-AGB -- stars: mass loss -- infrared: stars

Stability of Rarefaction Wave for Compressible Navier-Stokes Equations on the Half Line

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Acta Mathematicae Applicatae Sinica 2016年第1期32卷 175-186页

作者： Li-hua MIN xiao-hong QIN School of Science Nanjing University of Posts and Telecommunications Department of Mathematics Nanjing University of Science and Technology

This paper is concerned with the large-time behavior of solutions to an initial-boundary-value problem for full compressible Navier-Stokes equations on the half line（0,∞）,which is named impermeable wall *** is shown that the 3-rarefaction wave is stable under partially large initial perturbation if the adiabatic exponent γ is close to *** partially large initial perturbation means that the perturbation of absolute temperature is small,while the perturbations of specific volume and velocity can be *** proof is given by the elementary energy method.

关键词： compressible Navier-Stokes equations rarefaction wave stability