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    25 December 2004, Volume 2004 Issue 4 Previous Issue    Next Issue
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    Article
    Fusion Problem of Weak Solutions for A Class of Quasilinear Elliptic Equations
    Chen Hui-yu;Ran Qi-kang
    2004, 2004 (4):  1-5. 
    Abstract ( 2728 )   Save
    In this paper ,using geometric theory and special test function method, a sufficient condition for the solution of the fusion problem of weak solutions for a class of two order nonhomogeneous quasilinear el-liptic equations is obtained一div A(x,▽u)=B(x,u,Du).
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    Extensions of Cuntz Algebras
    LIU Shu-dong;LIU Jun-ping
    2004, 2004 (4):  6-9. 
    Abstract ( 2822 )   Save
    It is well-known that Extw (○n) ≌Zn-1. In this paper, we construct all the extensions of ○n by K in a new way, and compute their K-groups.
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    Equivalent Theorems for Various Uniform Stabilities of Discrete-time Nonlinear Systems
    WANG Zhi-ming;ZHENG Yu-fan;DAI Hao-hui
    2004, 2004 (4):  10-15. 
    Abstract ( 2675 )   Save
    Equivalent theorems in terms of class K functions are presented for uniform stability and uniform asymptotic stability of discrete-time nonlinear systems. On the base of the equivalent theorems, the theorem of uniform asymptotic stability for the discrete-time nonlinear systems and its comverse theorem are also obtained.
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    A Finite Difference Scheme for Nonlinear Reaction-diffusion Equations with Time Delay
    ZHANG Li-fang;WANG Yuan-ming
    2004, 2004 (4):  16-23. 
    Abstract ( 3192 )   Save
    A finite difference scheme with the accuracy of fourth order in space and second order in time is proposed for solving a nonlinear reaction-diffusion equation with time delay. Existence and uniqueness of the solution is given by the method of upper and lower solutions. A monotone iteration is also developed for the computation of the finite difference solution. The convergence of the scheme is discussed. The numerical results shows the advantages of the method.
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    Estimators of Parameters in A Single Index Time Series Model
    ZHANG Ri-quan;
    2004, 2004 (4):  24-27. 
    Abstract ( 2811 )   Save

    This paper gives a solution to the problem of estimating coeffcients of index model in a time series. The kernel estimate method and the average derivative method are employed. Under the data being β-mixing depentent,the asymptotic normality of the estimator are established.

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    Upper Bounds on the Spectral Radius of Digraphs
    FANG Kun-fu;SHU Jin-long
    2004, 2004 (4):  28-32. 
    Abstract ( 3160 )   Save
    In this paper, using the matrix theory, we present a sharp upper bound on the spectral radius of digraphs in terms of the out-degree sequence. Meanwhile, we characterize the extremal digraphs which spectral radius reaches the upper bound.
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    Bayesian Spline Nonparametric Regression
    LU Yi-qiang;MAO Shi-song
    2004, 2004 (4):  33-39,9. 
    Abstract ( 3178 )   Save
    In this paper the nonparametric regression model y= f(x)+ε, where f (x) is a smoothing function, is considered. The nonparametric regression f (x) is approximated by a spline function. The knot number is not fixed but given a noninformation prior, by which the uncertainty of the knot number is studied. The regression f(x) is estimated by the method of Bayesian model averaging and the posterior interval is also estimated.
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    Design and Development of A Microwave Cardio Graph Meter
    HUNG Yong;AN Tong-yi;QIAN Jian;FAN Ming-jie
    2004, 2004 (4):  40-47. 
    Abstract ( 2662 )   Save
    A design of Microwave Cardio Graph Meter (MCG),by which human signal can be extracted is proposed in this paper. Features: 1 150 MHz continuous ca rrter wave; Cancellation of un-modulated carrier wave by Zero-balance technique; Using forward scattering wave to improve performance. Experiments show that: the apparatus is simple in structure, and works steadily with high sensitivity and low noise. The MCG graphs are presented and discussed in detail.
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    The Design of the GPRS Mobile Telephone System on Wireless Module
    XU Min;LIU Jin-gao
    2004, 2004 (4):  48-51. 
    Abstract ( 2667 )   Save
    This article introduces the GPRS mobile telephone designing method based on wireless module and MCU. On the basis of a brief description of the national actuality concerning the GRPR mobile telephone R&D, the author gives the system’s schematic. This article also presents hardware and software design of the system, which provides some hints for the R&D engineer on the GPRS mobile telephone designing.
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    The Design of SMS based on PDA and Wireless Module
    Tong Xiao-hui;Gu Zeng-hui;Liu Jin-gao
    2004, 2004 (4):  52-55. 
    Abstract ( 2830 )   Save
    This article introduces the serial communication based on Windows CE. With a wireless module, PDA send SMS to the especial service center. The content of SMS include the GPS information and the service information that the user requires. The service center returns the information that is required by the user in the form of SMS. This article emphasizes the design and programming of SMS.
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    The Pulsed Electric Field Effect on the Cell Signal Pathway Mediated by Insulin
    DAI Yu-wen;DING Li-ping;LI Le-jun;ZHANG Hong-feng;XIA Ruo-hong;CHEN Shu-de
    2004, 2004 (4):  56-63. 
    Abstract ( 2935 )   Save
    Insulin was exposed to the pulsed electric field (PEF) for 0 min or 20 min before being added to the culture medium containing L-02 human hepatocytes. Thirty minutes later, the tyrosine phosphorylation level of the cells for each group was monitored by a flow cytometry. The average fluorescent intensity of the test cell groups decreased by 10.33% compared with the control groups. After the cells were cultured in the medium with the exposed insulin or the normal insulin for 68 hours, the gene expression levels were measured by using a gene expression chip. The change of fifty-five out of 12,000 gene sequences of the test groups were obvious compared to the controls. The human tyrosine phophatase mRNA showed increases in their expressions. These results suggested that, the intercellular signal molecule such as insulin can be the target of the electromagnetic field, and acts as a signal carrier of the information of PEF, which consequently causes its biological effects.
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    A Study on the Pattern of Land-use in Arid Area of Northwest China with RS and GIS------A Case of Wuwei City in Gansu Province
    YUE Wen-ze;XU Jian-hua;XU Li-hua
    2004, 2004 (4):  64-71. 
    Abstract ( 3545 )   Save
    Based on RS&GIS technique and quantitative analysis method and fractal model. We can reveal the main characters and dynamic process of the pattern of land-use in arid area. Our conclusions are as followings: (1) In Wuwei city the types of land-use were simplex, the density of land-use patches was small. (2) From 1995 to 2000 the diversity of the pattern of land-use had a little increase, while the dominance decreased comparatively. The fragmentation difference of all kinds of land-use was big. (3) In the terms of the simulative result with fractal model, the nature land-use influenced lower by humankind have more complexity than man-power land-use, the stability is reverse, The residential area and independent mine industry, water area were the most stable and simple land-use, while the farmland and grassland were the most complicated and unstable land-use. In the timescale the complexities of almost all land-uses in the pattern of land-use were increased while the stabilities were depressed. (4) The main factors that effect and control the pattern of land-use were complicated, there were three main factors region background, nature conditions and human activities. We should adopt reasonable measures to prevent the process.
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    Impact of the Estuarine Funnel Shape on the Formation of Turbidity Maxima
    FU De-jian;ZHU Jian-rong;SHEN Huan-ting
    2004, 2004 (4):  72-78. 
    Abstract ( 3881 )   Save
    Using the improved ECOM model and suspended sediment transportation model, the impact of the estuarine funnel shape on the estuarine turbidity maximum zone formation is studied with an idealized strait and funnel-shape estuary designed in this paper. There exists turbidity maximum zone at stagnation point, and its center locates at south side of the river coast. The reason of formation of estuarine turbidity maximum zone was revealed in terms of dynamic mechanism. Compared with the case of the strait estuary, the current divergence induced by the spreading width of funnel-shape estuary inner the mouth makes the current weaken, the distance of land-ward flow of density current at bottom layer induces, and the saltwater intrusion strengthens in the funnel-shape estuarine area. In addition the landward density induced current of bottom layer and its westward flowing distance increases. The westward intrusion distance of saltwater in the strait river channel region increases. The concentration of suspended sediment in the funnel-shape estuary decreases, but there are two turbidity maximum zones in it. One lies in the strait river way. Because the stagnant point moves toward upstream, its position relevantly moves toward upstream. However, the other lies in the south coast of the funnel-shape estuary area. It is mainly induced by the river flow, which turns toward the south coast under the effect of Coriolis Force, and the bottom transverse circulation which transport high concentration suspended sediment to the south coast. The variation of the river mouth shape has obvious impact on the estuarine circulation, the salinity intrusion and the turbidity maximum zone.
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    The construction and application of a variable fertilizer model based on GIS
    DU Jing-long;;JIANG Li-ping
    2004, 2004 (4):  79-83. 
    Abstract ( 2956 )   Save
    By the data sampled from wusi farm ,input of fertilizer and the degree of the soil index of fertilizer are calculated using the empirical formula . At the same time,the variable input map of fertilizer and the fertilizer map are maped using GIS. The result shows:There exits difference with the fertilizer whin the field and the input of fertilizer is different too.
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    Studies on Electron Microscopic Enzymo-Cytochemistry of Organelles of Vegetative- and Resting-cell in Euplotes encysticus
    Ni Bing;Sui Shuguang;Gu Fukang
    2004, 2004 (4):  97-102. 
    Abstract ( 3153 )   Save
    The electron microscopic enzymo-cytochemistry is used to study on the organelles in both vegetative- and resting cells of Euplotes encysticus. The results revealed that: (1)The reaction particles of adenosine triposphatase (ATPase) was tightly confined to the membrane of food vacuoles in the vegetative cells, while in the resting cells they gathered around the pellicle. (2)In the vegetative cells, the localization of the reaction particles of acid phosphatase (ACPase) was in the food vacuoles or the autophagic vacuoles of different stages, while in the resting they formed the vacuolar or spherical bodies. (3)The reaction particles of succinate dehydrogenase scattered on the mitochondrial in the vegetative cells, though they could also be seen in the scattered mitochondria in the resting cells, its activity was weaker than that of the former. Thus it was supposed from the above results: (1) In most cases, the enzyme activities in the resting cells were weaker than in the vegetative cells. (2) The enzyme activity and localization might be different in different kinds of resting cells. (3) The resting cells could also have digestive duration, energy consumption and functional mitochondria.
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    Comparative Investigation of Morphogenesis and Isoenzymes between the Wild Cells KAX-3 and the Mutant Cells AK127 during the Dictyostelium Discoideum Development
    HOU Lian-sheng;MA Ning-sha;WANG Yue;HAN Yi;FU Zhuo-ming
    2004, 2004 (4):  103-110. 
    Abstract ( 4361 )   Save
    Studying the morphogenesis of Dictyostelium discoideum development, we found that there were distinct differences between the wild cells KAX-3 and the mutant cells AK127(LagC gene was knockout). The mutant cells AK127 was blocked at loose aggregation stage for lacking gp150 during developmental stages. However, the wild cells KAX-3 completed the whole developmental stages successfully. Three isoenzymes were obtained from developing cells of Dictyostelium discoideum which included a wild type cells(KAX-3) and a mutant type cells Compared these isoenzymes by gel electrophoresis, we found that two different esterases appreared in AK127 while only one in KAX-3. Furthermore, the content of malate dehydrogenase (MDH) is more in AK127 than in KAX-3 at different developing stage. At 14h during development, the content of glutamate dehydrogenase (GDH) in AK127 is higher than in KAX-3;but at 16h GDH in AK127 is lower than in KAX-3. From the results, we learned that the pattern of some isoenzymes were changed between wild cells and mutant cells during development stage, indicating some changes in the expression of some genes. So it seemed that gp150 was an important factor in development.
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    Histology of the Male Reproductive System in Daphnia (Ctendaphnia) carinata
    ZHANG Ming-feng;;ZHAO Yun-long;ZEN Cuo;TANG Wen-jun
    2004, 2004 (4):  111-116. 
    Abstract ( 3021 )   Save
    The male reproductive system of Daphnia (Ctendaphnia) carinata is composed of a pair of testes, deferens and one male gonopore. The wall of the sausage-shaped testis is composed of connective tissue and germinal epithelium inside. The tube-shaped deferens, which gets larger at the end of it, is mainly made up of connective tissue. The spermatogenesis includes five stages: spermatogonium、primary spermatocyte、secondary spermaticyte、spermatid and spermatozoon. The mature sperm is clubbed and the spermatogenesis shows a tendency of synchronization. The sexual maturation experiences four stages. The male reproductive system retains its primative characters on structure and function, but it has also made up its adaptability through the long-time evolution, which enables Daphnia (Ctendaphnia) carinata and other species of Cladocera to live with the changeable living environment.
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    Population structure of Heptacodium miconioides, an endangered species, in Dapan Mountain of Zhejiang Province
    LI Ming;GU Yong-jie;ZHANG Xin;CHEN Xiao-yong
    2004, 2004 (4):  117-121. 
    Abstract ( 3180 )   Save
    Heptacodium miconioides Rehd. (Caprifoliaceae), seven-son-flower, is an endangered species endemic to China. The population structure of H. miconioides was analyzed at genet and ramet levels, respectively, in Dapan Mountain of Zhejiang Province. No individual of size class I (height<0.33m) was found in all studied sites. Size-class III and IV had most abundant individuals. At ramet level, size-class II and III had most abundant stems. Generally, size-class structure indicated a relatively stable situation in Dapan Mountain. However, in some sites, H. miconioides had the risk of local extinction. Sites at mid-altitude had lowest stems per individual, whereas more stems per individual were found at lower or higher sites. Individuals of the largest size class (size class V) had significant more stems per individual than size class III and critically significant more than size class IV. Our observation indicated that the population of Dapan Mountain was regenerated via asexual reproduction. These results showed that H. miconioides in Dapan Mountain could be maintained if no dramatic changes in the habitats. A reserve should be set because Dapan Mountain may be the largest population of H. miconioides.
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    Comparison of Two Kinds of Fast Food Container Using the Life-Cycle Assessment (LCA) Methodology
    Lin Feng-chun;Yang Kai
    2004, 2004 (4):  122-130. 
    Abstract ( 3315 )   Save
    Disposable expanded polystyrene fast food container is one of the main causes of “white pollution”. A comparison study on Expanded polystyrene(EPS) fast food containers and photicly/bioticly degradable ones has been carried out using the life-cycle assessment (LCA) methodology. The result shows that the environmental impacts of the two kinds of fast food container are mostly originated from production stage, and the main impacts are resources damage. The environmental harmony of EPS fast food container is higher than photicly/bioticly degradable ones when 70% of it is collected and recycled after being used. A comparison study on waste disposal scenarios shows that collecting and recycling has less environmental impacts than incinerating or landfilling for EPS fast food container, and incinerating has less environmental impacts than landfilling for photicly/bioticly degradable fast food containers. Some suggestions on ecological design of two kinds fast food container are put forward.
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