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SALT-FINGERING OF POLLUTANT VERTICAL MIXING IN STATIC THERMAL-STRATIFIED WATER

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Journal of Hydrodynamics 2010年第3期22卷 430-437页

作者： CHEN Bo LUO Lin LI Jia BAI Xue LI Shao-bo State Key Laboratory of Hydraulics and Mountain River engineering Sichuan University Chengdu 610065 China college of Architecture and Environment Sichuan University Chengdu 610065 China

Pollutant vertical mixing in stratified waters is a key factor that affects the vertical pollutant distribution in deep thermal-stratified reservoirs. This article presents an experimental study of the vertical mixing in thermal-stratified waters and an analysis of the retarded tracer jet diffusion in the thermocline layer. In the experiment, Reynolds number rapidly decreases from 104 to 10I. The stronger the stratification, the more seriously retarded the mixing will be. Some small tracer blobs may penetrate the thermocline layer into the hypolimnion layer even the main tracer cloud is retarded. According to its appearance, it can remain with salt-fingering, where the blobs are isolated away from the main cloud and mixed with the surround cold water in the hypolimnion layer. Therefore, the vertical distribution of the tracer under the thermocline layer would take larger values than expected. According to measurements, the isolated blob contents are accounted for about 5.-2.% of the main tracer cloud, and are decreased with the increase of the stratification intensity. Results also show that the stronger the stratification, the smaller finger width would be. The averaged width of the incipient fingers is proportional to -0.32.2.of the thermal Rayleigh number, Rat, in the turbulent jet fluid. power of the temperature gradient, AT/Az, or - 0.2.2. power

关键词： thermal-stratified water vertical mixing retard double diffusion salt-finger

Sufficient and necessary conditions for Lyapunov stability of Lorenz system and their application

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Science china(information Sciences) 2010年第8期53卷 1574-1583页

作者： LUO Qi 1 , LIAO XiaoXin 2.& ZENG ZhiGang 2.1 college of information and Control, Nanjing University of information Science and technology, Nanjing 2.0044, china 2.Department of Control Science and {5., Huazhong University of Science and technology, Image Processing and Intelligent Control Key Laboratory of Education Ministry of china, Wuhan 430074, china 1. college of information and Control Nanjing University of Information Science and Technology Nanjing 210044 China2. Department of Control Science and Engineering Huazhong University of Science and Technology Image Processing and Intelligent Control Key Laboratory of Education Ministry of China Wuhan 430074 China

The sufficient and necessary conditions for Lyapunov stability of the zero equilibrium point of Lorenz system are discussed, and some brief criteria are presented for globally exponential stability, globally asymptotical stability and instability. Furthermore, the behavior of the non-zero equilibrium point of Lorenz system is also investigated, and several sufficient and necessary conditions are provided for locally exponential stability and instability. The established theorems in this paper develop and extend the existing achievements on Lyapunov stability of Lorenz system. In conclusion, by applying the obtained results, some less conservative feedback-control laws are derived to guarantee the globally exponential stability of the chaos control of Chen system, Lu¨ system, Yang-Chen system and Yu-Xia Li system.

关键词： Lorenz system Lyapunov stability sufficient and necessary condition bifurcation values globally exponential synchronization

Study on Time Varying Conditional Correlations of Stock Market Returns Based on Multivariate GARCH model

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Study on Time Varying Conditional Correlations of Stock Mark...

2.10 2.d IEEE International Conference on Advanced Management Science（IEEE ICAMS 2.10）

作者： Yu Lin Business School chengdu University of technology chengdu P.R.china 610059Yanxiang Chen {5. of information Management chengdu University of technology chengdu china 610059

This paper uses multivariate GARCH model to model covariance matrix of Shanghai stock integration index,Hangsheng index of Hong Kong stock market and Nikkei 2.5.index of Tokyo stock market,and analyze time-varying conditional correlations of returns and volatilities of these three index *** results show that conditional returns of them are of time varying conditional correlations and their covariance matrices are also varying with the time.

关键词： Multivariate GARCH model Return of integration index Time Varying Conditional Correlations Volatility.

来源： cnki会议评论

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傅里叶系数为周期脉冲函数的信号研究

数据采集与处理 2010年第S1期25卷 69-71页

作者：刘唯一成都理工大学信息工程学院成都610059

通过对傅里叶系数为周期脉冲的信号的一般规律的讨论和分析,研究了上述信号的一般数学表达式,给出了一系列具体的公式,运用此类型的公式,在运算这类型信号的时候便可以大大简化推演过程,并在给出该系列公式后,运用一个实例说明了这类型... 详细信息

通过对傅里叶系数为周期脉冲的信号的一般规律的讨论和分析,研究了上述信号的一般数学表达式,给出了一系列具体的公式,运用此类型的公式,在运算这类型信号的时候便可以大大简化推演过程,并在给出该系列公式后,运用一个实例说明了这类型公式的具体用法。通过该实例可以清楚地看到,使用本文中推出的一般规律,对于这类型的信号,便可以省略纷繁复杂的数学运算,达到对于该类型信号简化计算的目的。

关键词：傅里叶系数周期信号脉冲函数

The structural analysis of fuzzy measures

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Science china(information Sciences) 2011年第1期54卷 38-50页

作者： ZHANG Ling1,ZHANG Bo2.& ZHANG YanPing1 1 Computer Science college,Anhui University,Hefei 2.0039,china 2.tate Key Lab of Intelligent {2. & Systems Tsinghua National Lab for information Science & {2. information Science & {2. college,Computer Science & {2.,Tsinghua University,Beijing 100084,china 1. Computer Science college Anhui University Hefei 230039 China2. State Key Lab of Intelligent Technology & Systems Tsinghua National Lab for information Science & technology information Science & technology {2. Computer Science & Technology Tsinghua University Beijing 100084 China

From quotient space based granular computing theory we explore the fuzzy measures of fuzzy sets. Based on the structural analysis of fuzzy sets,we present an"isotropism"*** this assumption we achieved the following insights:(1)the uniqueness of a fuzzy measure being isotropic on a finite complete semi-ordered set;(2.the necessary and suffcient condition of the isomorphism for fuzzy measure functions in fuzzy mathematics;(3)the necessary and suffcient condition that fuzzy measures have fuzzy and granular monotonicity;(4)under a certain assumption,the analytic expression for fuzzy *** results clarify the relationship between fuzzy measures and granular computing,reveal the essence of fuzzy measures,and provide a simple way of constructing fuzzy measures.

关键词： quotient space fuzzy set fuzzy measure rough set structural analysis

Design and Expression of a Synthetic phyC Gene Encoding the Neutral Phytase in Pichia pastoris

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 803-811页

作者： Li-Kou ZOU~(1,3) Hong-Ning WANG~(2.1*) Xin PAN~4 Tao XIE~1 Qi WU~5.Zi-Wen XIE~1 Wan-Rong ZHOU~1 1 Laboratory of Veterinary and Biotechnology,{2. Agricultural University,Ya'an 62.0}14,china 2.5} University Bioengineering Research Center for Animal Disease Prevention and Control,{5. 610065.china 3 Faculty of Environment and Resource of Dujiangyan Campus,{2. Agricultural University,Dujiangyan 611830,china 4 {12. of Earth Science,Chengd University of technology,{5. 610059,china 5.{12. of Life Science,{2. Agricultural University,Ya'an 62.0}14,china Laboratory of Veterinary and Biotechnology Sichuan Agricultural University Ya'an 625014 China

The 1074-bp phyCs gene （optimized phyC gene） encoding neutral phytase was designed andsynthesized according to the methylotrophic yeast Pichia pastoris codon usage bias without altering theprotein *** expression vector,pP9K-phyCs,was linearized and transformed in *** of total extracellular phytase activity was 17.6 U/ml induced in Buffered Methanol-complex Medium（BMMY） and 18.5.U/ml in Wheat Bran Extract Induction （WBEI） medium at the flask scale,respectively,improving over 90 folds compared with the wild-type *** enzyme showed temperature optimumof 70℃ and pH optimum of *** enzyme activity retained 97% of the relative activity afterincubation at 80℃ for 5.*** of the heavy glycosylation the expressed phytase had a molecularsize of approximately 5. *** deglycosylation by endoglycosylase H （EndoH_f）,the enzyme had anapparent molecular size of 42.*** property and thermostability was affected by the glycosylation.

关键词： design expression synthetic phyC gene neutral phytase Pichia pastoris

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惰性气体输运性质的理论计算

物理学报 2002年第3期51卷 497-500页

作者：郭建军四川工业学院电子信息与电气工程系成都610039

利用惰性气体原子间相互作用势 ,系统计算了 5.惰性气体的输运系数 ,包括第二维里系数B、扩散系数D、热传导系数λ、黏滞系数 η和热扩散因子αT 的计算 .从输运性质的计算证明了Tang Toennies势模型的准确性 .

关键词：惰性气体 Tang-Toennies势模型输运系数理论计算输运性质扩散系数

ON F-z-SUPPLEMENTED SUBGROUPS OF FINITE GROUPS

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Acta Mathematica Scientia 2011年第1期31卷 22-28页

作者：郭文彬唐娜李保军 Department of Mathematics University of Science and Technology of China Department of Mathematics Xuzhou Normal University Department of Mathematics Huaiyin Teachers College School of Mathematics Chengdu University of Information Technology

A subgroup H of a group G is called F-z-supplemented in G if there exists a subgroup K of G, such that G = HK and H∩K≤ Z∞F（G）, where Z∞F（G） is the F-hypercenter of G. We obtain some results about the F-z-suppl... 详细信息

关键词： Finite groups local formations F-z-supplemented subgroups supersoluble groups p-nilpotent groups

ON THE ALMOST SURELY ASYMPTOTIC BOUNDS OF A CLASS OF ORNSTEIN-UHLENBECK PROCESSES IN INFINITE DIMENSIONS

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Journal of Systems Science & Complexity 2008年第3期21卷 416-426页

作者： Yuhong LI college of Hydropower and information {2. Huazhong University of Science and Technology Wuhan 430074 China

Given a real-valued separable M-type 2.Banach space X with the p-th power of the norm of C2.class, the almost sure asymptotic upper bounds of the solutions of the Ornstein-Uhlenbeck Processes described by the following equations {dz（t）=A（t,z（t））dt＋σ（t,z（t））dW（t）,z（0）=z0∈X,are investigated. This study generalizes the corresponding well-known finite dimensional results of Lapeyre （1989） and Mao （1992..

关键词： Almost surely asymptotic bounds infinite dimension M-type 2.Banach space Ornstein-Uhlenbeck Processes