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    25 September 2004, Volume 2004 Issue 3 Previous Issue    Next Issue
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    Existence and Uniqueness of Limit Cycle for A Nonlinear Equation
    LIU Xing-bo
    2004, 2004 (3):  1-5,28. 
    Abstract ( 3406 )   Save
    This paper considers the existence and uniqueness of limit cycle for a planar autonomous system x=Q(x,y), y=P(x). The conditions of existence of limit cycle in papers [7~9] are simplified, in addition, The uniqueness of limit cycle is discussed. Simpler conditions for the existence and uniqueness of limit cycle are obtained.
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    Normal Families Concerning Differential Polynomial
    WANG Xiao-jing;;PANG Xue-cheng
    2004, 2004 (3):  6-10. 
    Abstract ( 2786 )   Save
    In this paper a general normal criterion is obtained, which improves the results given by Gu YX[1] and Zhu JH[2]. Let F be a family of meromorphic functions on domain D, all of whose zeros are of multiplicity at least m+3. Let h≠0, a0, a1, …, am-1 be holomorphic functions on D. If for any f∈F, L(f)(z)=f(m)(z)+am-1(z)f(m-1)(z)+…+a1(z)f′(z)+a0(z)f(z)≠h(z), z∈D, then F is normal on D.
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    A Variational Proof of the Firey 2-sum Christoffel Problem
    HU Chang-qing;WANG Pei-he;SHEN Chun-li
    2004, 2004 (3):  11-15. 
    Abstract ( 2604 )   Save
    In this paper, we take a direct method in calculus of variation to discuss some linear equation on Sn and get the existence and the uniqueness of its positive solution, by this method we give a proof for the Firey 2-sum Christoffel problem.
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    Reverse Order Laws for Generalized Inverses of Matrices on An Arbitrary Skew Field
    LIU Yong-hui;GONG Zi-kun;WEI Mu-sheng
    2004, 2004 (3):  16-21. 
    Abstract ( 2972 )   Save
    In this paper, we prove a decomposition theorem of matrix pair over an arbitrary skew field. By applying the decomposition theorem, we obtain some neccessary and sufficient conditions of reverse order laws for g-inverse and reflexive g-inverse of matrix products on an arbitrary skew field.
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    On the Spectral Radii of Trees
    WU Bao-feng;YUAN Xi-ying;XIAO En-li
    2004, 2004 (3):  22-28. 
    Abstract ( 3572 )   Save
    We focus on the ordering of trees on n vertices and determine seven trees with small spectral radii. We also consider the following problem: of all trees with maximal degree 3 on n vertices which achieves the minimal and maximal spectral radius when the vertices number of degree 3 is one, two and three, respectively?
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    Inertial Fractal Set for Complex Ginzburg-Landau Equation in Three-dimension
    LI Dong-long;GUO Bo-ling
    2004, 2004 (3):  29-35. 
    Abstract ( 2769 )   Save
    This paper considers the complex Ginzburg-Landau equation in three spatial dimensions. The Lipschitz continuity and the squeezing property of the semigroup S(t) associated with the initial-value problem of complex Ginzburg-Landau equation are proved. Therefore the existence of inertial fractal sets is obtained.
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    The Waiting Time Problems of Patterns
    HAN Qing
    2004, 2004 (3):  36-41,9. 
    Abstract ( 2617 )   Save
    This paper considers the waiting time problems of pattern S0 and S1 in a Markov dependent sequence. The probability functions and the probability generating functions of the sooner and later waiting time between pattern S0 and pattern S1 are obtained. Also obtained are the probability functions and the probability generating functions of the waiting times of patterns S0 and S1.
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    Comparison of Two Bayesian Models
    PU Xiao-long;XU Jing
    2004, 2004 (3):  42-47,1. 
    Abstract ( 2882 )   Save
    This article discusses the difference between two Bayesian models. With model 1, it is assumed that xi(i=1,2)is conditional independent under θi(i=1,2). While with model 2, it is assumed that xi(i=1,2)is unconditional independent. The question is that when working for the Bayesian estimation of θ1, is there any difference on the results under the two different models? The numerical comparison shows that there is only small difference between the results. So the simpler model 2 can replace the model 1, when Bayesian estimation of θ1 is calculated.
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    Stochastic Orders of Exponential Family
    GONG Hai-lin;ZHANG Xin-sheng
    2004, 2004 (3):  48-53. 
    Abstract ( 2613 )   Save
    This paper investigates the likelihood ratio order and the increasing convex (concave) order for exponential family of distributions. Some sufficient conditions to these orders are obatined.
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    Skew Detection for Form Document Using Vertex-chain-code
    ZHANG Sheng-xi;ZHANG Wei;LI Guo-qiang;GU Guo-qing
    2004, 2004 (3):  54-58. 
    Abstract ( 2881 )   Save
    In view of the fact that frame lines and hanging lines of a form image have the longest boundary and the boundary-labeling-automaton gives Vertex-Chain-Code of region boundaries easily, this paper proposes a new method for skew detection for a form image. The algorithm is efficient and robust against strong noise.
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    A Theoretical Model of Gap Junction Intercellular Communication and Its Electric Magnetic Field Suppression
    QI Hong-xing;CHEN Shu-de;QIAO Deng-jiang
    2004, 2004 (3):  59-65. 
    Abstract ( 2866 )   Save
    We establish a theoretical model of gap junctional intercellular communication (GJIC) and its suppression effect by electric-magnetic fields. The model is based on the self-organized critical states of cells and gap junction, and we also discuss the information sink, information lock, information channel, which play essential rules in communicative function of the cell membrane and the EM effect. The result can be used to explain the experiment data and the suppression of GJIC by 50 Hz magnetic field.
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    The Timing Problem of Synchronous Design in FPGA/CPLD
    LEI Jian-hong;JING Zhi-cheng;SHEN Jian-guo
    2004, 2004 (3):  66-70,9. 
    Abstract ( 2802 )   Save
    This paper discusses the timing problem in FPGA/CPLD design. It digs out the reasons of this kind of problem and the influence of them on design. Finally, it concludes with some resolutions for the timing design.
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    A New Static-electronic Driving Variable Optical Attenuator
    YANG Zhen;LI Guo-dong;PENG De-yan;XIN Pei-sheng;LAI Zhong-sheng;ZHU Zi-qiang
    2004, 2004 (3):  71-75. 
    Abstract ( 2762 )   Save
    Optical attenuator is a key component in a fiber network. This paper reports a new kind of Silicon-based Variable Optical Attenuator(VOA) based on Micro-Opto-Electro-Mechanical System(MOEMS) technique. The device is designed to work on the wavelength range of 1 320 nm to 1 550 nm.
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    ESR Study on the Photoinduced Production of Hydroxyl Radicals by Nano-TiO2
    AI Shi-yun;YANG Ya;XIAN Yue-zhong;LI Jia-qing;LI Luo-ping;JIN Li-tong
    2004, 2004 (3):  76-81. 
    Abstract ( 3423 )   Save
    In nano TiO2 photocatalytic oxidation system, adding inorganic oxidizing species can efficiently trap photogenerated electrons and increase concentrations of hydroxyl radicals in the solution and enhance the photocatalytic oxidation rate of nano TiO2 to different organic matter. In this study, correlation of the production of hydroxyl radicals and the photoinduced electron tranfer of nano-TiO2 by inorganic oxidizing species (K2S2O8) was verified by means of the free radicals measured by spin trapping-ESR methods in which DMPO was selected as the spin-trap. The photocatalytic oxidation mechanism of glycine was studied.
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    A Proposal to Build Meimaosha Reservoir as A New Water Resource for Shanghai
    CHEN Ji-yu;CAO Yong;LIU Jie;CHEN Shen-liang
    2004, 2004 (3):  82-86. 
    Abstract ( 3079 )   Save
    There is a rapid increase in utlilzing the fresh water resources with the development of Shanghai . According to the monitoring data in the first four months of 2003 near Pudong International Airport Dock, the authors think it is appropriate to build the Meimaosa reservoir between the Meimaosa sand ridge and Nanhui bank. The reservoir has huge capacity of about 200 million m3 and can fully utilize and store seasonal and discontinuous water resources. The water environment of Pudong will be greatly improved and its water demand can be satisfied. The advantages and disadvantages to build the reservoir, the multifunctional development of the reservoir and the work in advance needed to do are analyzed in this paper.
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    A Fractal Theory of the Urban System in Yangtze Delta
    LING Yi-ying;XU Jian-hua;YUE Wen-ze;Ai Bin
    2004, 2004 (3):  87-92. 
    Abstract ( 3206 )   Save
    This paper studies the Urban system in Yantze delta using fractal theory. We figures out the primate city index in Yantze delta according to the town primacy rule of M.Jefferson, and then the town-size fractal dimension is worked out to discuss to the scale structure of the urban system in Yantze delta. In addition, spatial correlation dimension of the town-size distribution in Yantze delta is put forward to analyses the spatial structure of urban system. According to all these analyses it points out there are some deficiencies of the urban system in Yangtze delta, such as:(1)The scale distributing in Yangtze delta is primacy distributing; (2) Middle-small cities develop much slower than big cities; (3) The capacity of spatial interaction isn’t strong enough. The paper puts forward the direction for developing the urban system in Yangtze delta: Realize the integration of regional economy, and speed up the development in Yangtzi delta.
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    The lmpact of Glutaraldehyde as Fixative on Marine Picophytoplankton
    ZHANG Li-hua;CHAO Min
    2004, 2004 (3):  93-98. 
    Abstract ( 3521 )   Save
    Samples are fixed with 1% glutaraldehyde and stored in liquid Nitrogen .Cell density、size and intensity of autofluorescence are compared with fresh samples in this experiment . The results showed that cell density and cell size of all three picophytoplanktonic populations(prochlorococcus、 synechococcus and picoeukaryotes) increased, but intensity of autofluorescence decreased.
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    A Study on SDSS-based Shanghai Flood Control Decision Support
    ZHENG Xiao-yang;YU Li-zhong;YANG Meng
    2004, 2004 (3):  99-104. 
    Abstract ( 3373 )   Save
    With rapid modernization of big cities, increasingly more problems have been found in urban flood control management and decision-making. Thus it is necessary to introduce SDSS theory and technology in order to optimize decision-making process. Based on characteristics of Shanghai flood control, and integrated with hydrology, meteorology, geomorphology, Geographic Information System, model database and knowledge database, a flood control SDSS was designed for the purpose of real-time monitoring and forecasting. Depending on the system, flood control departments can make scientific and reasonable decisions, and realize the objective of bringing flood control into modern administration.
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    Analysis of Microclimate Effects around River and Waterbody in Shanghai Urban District
    YANG Kai; TANG Min; LIU Yuan;WU E-nuo;FAN Qun-jie
    2004, 2004 (3):  105-114. 
    Abstract ( 4284 )   Save
    The air temperature (T) and relative humidity (RH) are observed for six different types of rivers and water bodies in Shanghai urban district. By comparing temperature-humidity features and human comfort degrees between the windward and leeward shores of these selected water bodies in different seasons, this paper attempts to analyze microclimate effects of urban river and waterbody effects. The results obtained are as follows: (1) The size of water area contributes greatly to microclimate effects. In observing period for several seasons, the T in the lake leeward decreased by 1~3 ℃ and the RH increased by 6%~14% compared to that in windward shore in Changfeng Park. (2) Building layout around waterbody affects the microclimate in some degree. Dense high buildings in Zhongyuan residential district transform the state of airflow, so a microclimate effect is formed near Suzhou brook. (3) Compound ecosystem composed by water and greenbelt can do well work for a microclimate effect. On condition of open green space near Zhangjiabang brook, the T in leeward shore is lower by 1.5~2 ℃ and the RH is higher by 4~8% than that in windward shore during observing periods. (4) The artificial facilities such as fountain, can improve the waterbody microclimate effect. Near artificial lake of Taipingqiao greenbelt, the difference of T and RH enlarged respectively by 0.3 ℃ and 4% when the fountain was working than it closed in the observing day. (5) The effect of human comfort degree displays more significant in warm spring-summer than it in cold and dry winter.
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    On Several Issues of East-Asiatic Bryophytic Immigration Route by the Characteristics of the Bryoflora of Eastern Jiufeng Mt.,Fujian,China
    ZHU Jun;WANG You-fang
    2004, 2004 (3):  115-120. 
    Abstract ( 3113 )   Save
    Based on the comparison and analysis of the principal geograpghical elements and East-Asiatic endemic genera in the bryofloras of Eastern Jiufeng Mt.and its adjacent regions,as well as the relationships with the bryofloras of Taiwan(China)and Japan,the conclusions are as follows:the bryoflora of Jiufeng MT.belongs to a transitional area; the bryophytic immigration route of Himalaya-Northern Guangxi-the Wuyi Mountains -Taiwan;the area including the eastern Jiufeng Mountain and the adjacent is worthy to be further explored for its bryophytes,because of the richness of the East-Asiatic endemic genera,the high degree of the species abundance,numerous new records for China of Fujian,and the presence of epiphyllous liverworts.
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    Protective Effects of Lycium Bararum Polysaccharides on Carbon Tetrachloride and High Glucose Damaged Hepatocytes
    ZHANG Hong-feng; XU Man-yan; WANG Yao-fa
    2004, 2004 (3):  121-125,. 
    Abstract ( 2786 )   Save
    Hepatocytes in vitro damaged by carbon tetrachloride (CCL4) and high glucose(HG) were used to research the mechanism of CCL4 and HG on the glucokinase(GK) activity,the intercellular Ca2+ concentration and the level of tyrosine phosphorylation in cells ,and then the protective effects of Lycium bararum polysaccharides(LBP).The results showed that CCL4 and HG inhibited the GK activity,elevated Caconcentration and decreased the level of tyrosine phosphorylation in hepatocytes. LBP could improve the change of the GK activity and Ca2+ concentration induced by CCL4 and HG, and the decrease of tyrosikinase activity in the pathway of insulin induced by CCL4 only.But LBP couldn’t improve the decrease of tyrosikinase activity induced by HG.The conclusion was that LBP could protect hepatocytes against free radicals directly,but not against the damage of HG. This related to the different mechanism of CCL4 and HG.
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    The Characteristics of the Acoustic Response of AⅠNeurons to the Frequency of Pure Tone
    HE De-fu;CHEN Fu-jun;ZHOU Shao-ci
    2004, 2004 (3):  126-130. 
    Abstract ( 2988 )   Save
    The characteristics of the acoustic response of AⅠneurons to the frequency of pure tone were investigated with extracellularly recording. The experimental results showed that the tuning curves of AⅠneurons could be classified into “V”, “W”, and “U” types. Q10 values and Q30 values of AⅠneurons increased with increasing of the characteristic frequencies (CFs) of these neurons. The results also showed the topographical distribution of the CFs of neurons in AⅠcortex. Generally the neurons with high CFs laid in the rostral part of AⅠ, and the neurons with low CFs laid in its caudal part. These results indicated that AⅠneurons with high CFs had more powerful frequency selectivity ability than that with low CFs, and that the frequency range of acoustic response of AⅠneurons widened with increasing of CFs of these neurons. The topographical distribution of the CFs in AⅠindicated that the coding on frequency of sound stimulation accorded with the rule of place coding.
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    Webbing the LMDS Remote Terminal(NOTE)
    PEI Jin-ming;SUN Hu;ZHU Shou-zheng
    2004, 2004 (3):  135-137. 
    Abstract ( 2341 )   Save
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