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Entropy Assessment on Environmental Influence of Condense Heat in Recovery System in Air-Conditioning Refrigerating Machine

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湖南大学学报（自然科学版） 2009年第S1期36卷 96-101页

作者： TANG Wen-wu1,2.WANG Han-qing1,2.1.school of Energy {3. and {2.,central south University,changsha,Hunan 4.0083.china 2.school of Civil {2.,Hunan University of Technology,Zhuzhou,Hunan 412.08,china) school of Energy science and {2. Central South University Changsha 410083 China school of Civil engineering Hunan University of Technology Zhuzhou 412008 China

This paper presented an entropy evaluation method for the influences of condense heat recovery system on the *** at the damage of the condense heat to the environment,an entropy of resource loss and an emission entropy from the condense heat recovery system in the air conditioning refrigerating machine were *** the evaluation of the entropies,we developed a new algorithm for the parameter identification,called the composite influence coefficient,based on the Least Squares Support Vector Machine *** simulation,the numerical experiments shows that the Least Squares Support Vector Machine method is one of the powerful methods for the parameter identification to compute the damage entropy of the condense heat,with the largest training error being-0.02.(the relative error being-3.56%),and the biggest test error being 0.015(the relative error being 2.5%).

关键词： air-conditioning refrigerating machine condense heat entropy evaluation LS-SVM

On the design of compensator for quantization-caused input-output deviation

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science china(Information sciences) 2011年第4期54卷 824-835页

作者： GUO YuQian,GUI WeiHua & YANG ChunHua school of Information science and {2.,{3. south University,changsha 4.0083.china 1. school of Information science and {2. Central South University Changsha 410083 China

This paper considers the design of compensators for systems with quantized inputs in order to reduce the influence of *** systems with (vector) relative degrees,we propose a kind of compensators which can compensate for the accumulated output deviation completely caused by *** proposed compensators are capable of keeping the differences of the input-output responses between the systems with quantized inputs and the original systems without considering quantization within certain small *** show that the compensators in this paper are robust with respect to model uncertainties,disturbance and measurement noise and can significantly improve the input-output responses of systems with both input quantization and packet dropouts.

关键词： networked control systems quantization packet dropout I/O deviation compensation

Decay parameter and related properties of 2.type branching processes

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science china Mathematics 2009年第5期52卷 875-894页

作者： LI JunPing school of Mathematical science and Computing Technology, {2. {3. University, changsha 410075, china 1. school of Mathematical science and Computing Technology Central South University Changsha 410075 China

We consider the decay parameter, invariant measures/vectors and quasi-stationary dis- tributions for 2.type Markov branching processes. Investigating such properties is crucial in realizing life period of branching models. In this paper, some important properties of the generating functions for 2.type Markov branching q-matrix are firstly investigated in detail. The exact value of the decay parameter λC of such model is given for the communicating class C = Z+2.\ 0. It is shown that this λC can be directly obtained from the generating functions of the corresponding q-matrix. Moreover, the λC-invariant measures/vectors and quasi-distributions of such processes are deeply considered. A λC-invariant vector for the q-matrix (or for the process) on C is given and the generating functions of λC-invariant measures and quasi-stationary distributions for the process on C are presented.

关键词： 2.type Markov branching process decay parameter invariant measures invariant vectors quasi-stationary distributions 60J2. 60J80

Preparation and characterization of nitrogen-doped titanium dioxides

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science china Chemistry 2007年第2期50卷 212-216页

作者： ZHU GuoPing1 & ZHOU KangGen2.1 Environmental science Research & Design Institute of Zhejiang Province,Hangzhou 3.0007,china 2.Department of Environmental {2.,school of Metallurgical science and {2.,central south University,changsha 4.0083.china 1. Environmental science Research & Design Institute of Zhejiang Province Hangzhou 310007 China 2. Department of Environmental engineering School of Metallurgical Science and Engineering Central South University Changsha 410083 China

A type of high visible-light active titanium oxinitride(TiO2.xNx) powder was prepared by a simple proc-ess:the calcination of the hydrated titanium dioxide at the atmosphere of ammonia-argon using a tu-bular electric furnace at high temperatures. The hydrated titanium dioxide was synthesized as the precursor of TiO2.xNx using titanic acid as raw material,which came from sulfate technique of produc-ing titanium white. The effects of temperature and reaction time on the nitrogen content,grain size and crystal structure were studied. The visible-light activity and photocatalysis capability of the powder were also investigated.

关键词： nitrogen-doped titanium dioxides visible-light activity photocatalysis titanium oxinitride

Ti/Al_2._3.Functionally Gradient material Prepared by the Explosive Compaction/SHS Process

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Journal of materials science & Technology 1999年第3期15卷 271-275页

作者： Yimin LI(Powder Metallurgy Research Institute, central-south University of Technology,{2.)Ziqiao ZHENG(Department of {3.s science and engineering, central-south University of Technology,{2.) Cent S Univ Technol Powder Met Res Inst Changsha 410083 Peoples R China Cent S Univ Technol Dept Mat Sci & Engn Changsha 410083 Peoples R China

Ti1Al2.3.Functionally Gradient material (FGM) was prepared by an explosive compaction/SHS process. Ten sheets of the compounding powder were laminated and pressed to get a green body of FGM. It was then compacted explosively By burying the explosive compaction body into a stoichiometric Al/TiO2.mixture and igniting the combustion of the stoichiometric Al/TiO2.mixture, the SHS reaction of the explosive compaction body was initiated by the heat released from the combustion of the stoichiometric Al/TiO2.mixture. In this way, Ti/Al2.3.FGM was synthesized. The adiabatic temperatures of each gradient layer were calculated when the preheating temperatures were 2.8 K and 1173.K, respectively The microstructure, composition and properties of Ti/Al2.3.FGM and the reaction mechanism of each gradient layer were studied. It was found that Ti/Al2.3.FGM prepared by the explosive compaction/SHS process had a high density and a high microhardness. Its structure, composition and properties showed apparent gradient distribution. The structure of the standard stoichiometric ratio gradient layer of FGM was a network structure. Its reaction mode could be described as follows: Al powder melted first, then the molten Al penetrated into the TiO2.zone and reacted with TiO2. and big pores were left in the original positions of Al powder. The reaction of gradient layers with the addition of Al3.3.as diluents was similar to that of the standard stoichiometric ratio gradient layer, so were their structure and composition. However, the reaction of gradient layers with the addition of Ti as diluents was more complex and the composition deviated slightly from the designed one

关键词： Al SHS Ti/Al2.3.Functionally Gradient material Prepared by the Explosive Compaction/SHS Process

Thermal Comfort in Waiting Room at Railway Station in Cold Region in china

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湖南大学学报（自然科学版） 2009年第S1期36卷 66-70页

作者： MA Wei-wu,CHEN Qian-zhou,ZHOU Jie-min,SHI Xiang-nan,LI Li-qing,WANG Chao,CHEN Zhi-ya(1.school of Energy science and {2.,{3. south University,changsha,Hunan 4.0083.china 2.Department of Mechanical {2.,Purdue University,Calumet,Hammond 463.2},USA 3.school of Traffic and Transportation {2.,{3. south University,changsha,Hunan 4.0083.china) school of Energy science and {2. Central South University Changsha 410083 China Department of Mechanical engineering Purdue University Calumet Hammond 46323 United States school of Traffic and Transportation engineering Central South University Changsha 410083 China

A field study and analysis about the thermal comfort was carried out in the waiting room at Beijing West Rail Station in Chinese cold ***' TSV(thermal sense vote)was obtained using statistical method on the basis of more than 1 2.0 *** linear regression between TSV and indoor temperature indicates that thermal neutral temperature is 2..2.℃.According to the percentage of satisfaction among all passengers under different indoor temperatures,the acceptable temperature range in the waiting room is 2..2.3..2..It is also found that passengers' temporary stay should be taken into consideration for the thermal comfort ***' TSV is not a constant value after they enter the waiting *** fact,ΔTSV increases as passengers are waiting for the train,and the growing rate is dependent on indoor-outdoor temperature *** greater the temperature difference,the faster ΔTSV *** last,a linear regression between indoor comfortable temperature and outdoor temperature was generated as the adaptive comfort model.

关键词： waiting room thermal comfort adaptive comfort model

A new method for spatio-temporal prediction of rainfall-induced landslide

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science china Earth sciences 2006年第4期49卷 421-430页

作者： DING Jixin1,2. YANG Zhifa2. SHANG Yanjun2. ZHOU Shenghua1 & YIN Juntao3.1. {3. Non-ferrous Metals Resource Geological Survey, Beijing 100012. {3. 2. Institute of Geology and Geophysics, Chinese Academy of {2.s, Key Laboratory of engineering Geomechanics, Beijing 10002., {3. 3. school of Geo{2. & Environmental engineering, central south University, changsha 4.0083. china 1. china Non-ferrous Metals Resource Geological Survey Beijing 100012 China 2. Institute of Geology and Geophysics Chinese Academy of Sciences Key Laboratory of Engineering Geomechanics Beijing 100029 China 3. school of Geoscience & Environmental {2. Central South University Changsha 410083 China

Geological condition and rainfall are two most principal conditions inducing landslides in the Chongqing region. By analyzing the forming conditions of rainfall-induced landslides, a new method for spatio-temporal prediction of rainfall-induced landslide is brought forward on the basis of grading and overlapping geological condition and rainfall factor in this paper. At first, semi-quantitative assessment and grading for the geological condition of a certain area or slope can be carried out with the multi-factor interactive matrix. Then the severity of rainfall in that area is grading according to the maximum daily rainfall and the total rainfall in a rainfall course. Finally, the “landslide probability judgement factor” can be worked out through grading and overlapping “geological condition influenc- ing factor” and “rainfall influencing factor”, by which the landslide can be graded into 4 grades, they are landslide extremely easily happening, landslide easily happening, landslide difficultly happening and landslide hardly ever happening respectively. More accurate spatio-temporal prediction of rain- fall-induced landslides can come true on the ground of detailed geological survey of some dangerous slopes in an area and more precise weather forecast. Finally, the reliability and feasibility of carrying out the spatio-temporal prediction of rainfall-induced landslides with the method of “two factors” grading and overlapping are validated by the example of Jipazi landslide.

关键词： rainfall-induced landslide, geological condition, rainfall, two factors, grading and overlapping, interactive matrix, spatio-temporal prediction.

Almost simple groups with socle ^3._4(q)act on finite linear spaces

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science china Mathematics 2006年第12期49卷 1768-1776页

作者： LIU Weijun, DAI Shaojun & GONG Luozhong school of Mathematics, central {2. University, {3. 410075, china Department of Mathematics, Hunan University of science and engineering, Yongzhou 42.006, china 1. school of Mathematics Central South University Changsha 410075 China 2. Department of Mathematics Hunan University of Science and Engineering Yongzhou 425006 China

After the classification of flag-transitive linear spaces,attention has now turned to line-transitive linear *** spaces are first divided into the point-imprimitive and the point-primitive,the first class is usually easy by the theorem of Delandtsheer and *** primitive ones are now subdivided,according to the O'Nan-Scotte theorem and some further work by Camina,into the socles which are an elementary abelian or non-abelian *** this paper,we consider the ***,T ≤ G ≤ Aut(T) and G acts line-transitively on finite linear spaces,where T is a non-abelian *** obtain some useful *** particular,we prove that when T is isomorphic to 3.4(q),then T is line-transitive,where q is a power of the prime p.

关键词： line-transitive,linear space,automorphism,almost simple group.

Analysis theory of random energy of train derailment in wind

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science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 751-757页

作者： CHEN RuiLin 1,2.3., ZENG QingYuan 3., HUANG YunQing 1 , XIANG Jun 3., WEN Ying 3., GUO XiaoGang 2., YIN ChangJun 2., DONG Hui 2.& ZHAO Gang 4 1 Hunan Key Laboratory for Computation and Simulation in science and engineering, Xiangtan University, Xiangtan 411105, {2. 2.school of Civil engineering & Mechanics, Xiangtan University, Xiangtan 411105, {2. 3.school of Civil Architecture, central {13. University, changsha 410075, {2. 4 AMEC, Toronto M5A5G7, Canada 1. Hunan Key Laboratory for Computation and Simulation in science and engineering Xiangtan University Xiangtan 411105 China2. School of Civil Engineering & Mechanics Xiangtan University Xiangtan 411105 China3. School of Civil Architecture Central South University Changsha 410075 China4. AMEC Toronto M5A5G7 Canada

Based on the analysis theory of random energy of train derailment, an analysis theory of random energy of train derailment in wind is suggested. Two methods are proposed -the time domain method and the frequency domain method of analysis theory of random energy of train derailment in wind. The curves of σ pw -v under various wind speeds are obtained through the computation. The original curve of σ p -v is expanded, which turns the analysis theory of random energy of train derailment into the all-weather theory. Train derailment condition has been established under wind action. The first and second criterions of train derailment have been proposed in light of wind action. The analysis of train derailment cases at home or abroad is made, in- cluding the first analysis of Xinjiang train derailment case encountered 13.level of gale, which explained the inevitability of train derailment. The analysis theory of random energy of train derailment in wind shows its validity and accuracy. The input energy σ pw of the transverse vibration of train-track(bridge)-wind system is linked to train speed. With the establishment of the analysis theory of random energy of train derailment in wind, It is likely to initiate an all-weather speed limit map for a train or any high-speed train.

关键词： train derailment analysis theory of random energy of train derailment analysis theory of random energy of train de- railment in wind train derailment condition in wind the criterion of train derailment in wind train derailment case