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    25 November 2010, Volume 2010 Issue 6 Previous Issue    Next Issue
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    Article
    Formation mechanism of Ruifeng Shoal ditch in the Yangtze River Estuary
    LI Yu-zhong;;CHEN Shen-liang
    2010, 2010 (6):  1-11. 
    Abstract ( 3061 )   PDF (6989KB) ( 1332 )   Save
    Based on history charts for the Yangtze River Estuary, formation mechanism of the Ruifeng Shoal ditch was analyzed. With the head part of the Shoal siltting southward, the upside mainstream direction turns southward in the South Channel. Bounced by southern bank, the mainstream will turn northward in the middle part of the South Channel and erode the lower part of the Ruifeng Shoal. Then a ditch on Ruifeng Shoal appears. In the end of 1990s, development of Baoshan North Channel and large amount of sediments from the Nanshatou Channel induced the siltation southward in the head part of the Shoal. The deduction was testified by the tidal current survey and the flow modeling.
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    Exploring the theoretical framework of object-oriented analysis for urban spatial information using remote sensing data
    YU Bai-lang;LIU Hong-xing;WU Jian-ping
    2010, 2010 (6):  12-25,6. 
    Abstract ( 2975 )   PDF (3877KB) ( 1674 )   Save
    In this study, three basic concepts: image object, geospatial object, and urban spatial object were examined, and the dissimilarities and relations among them were elaborated. Three criteriaboundary, attributes, and scale-were proposed to characterize different types of geospatial objects. This research reveals that each geospatial or urban spatial object is defined by three components: identity, state and behavior. These three components are represented by unique name (or identification number), attributes, and relationships respectively. In addition, the information associated with an object has three dimensions: theme, space and time. The thematic, spatial, temporal attributes and relationships are the information underpinnings of a geospatial and urban spatial object. As a significant result of this paper, a general framework for object-oriented analysis of urban spatial information is established. The author believes that this framework may have wide applications in the field.
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    Three dimension numerical simulation of thermal discharge from the Shidongkou electric power plant expand project in the Changjiang Estuary
    XU Sheng-yi;ZHU Jian-rong;CHEN Bing-rui
    2010, 2010 (6):  26-34. 
    Abstract ( 3076 )   PDF (4105KB) ( 1747 )   Save
    By using a improved three dimension numerical ECOM (estuarine, coastal and ocean model), the transport and diffusion of thermal discharge from the Shidongkou electric power plant expansion project in summertime was calculated and analyzed, in terms of the factors of tide, river runoff, wind stress and river surface heat flux. The calculated current speed and direction is consistent with the observed data fairly well, indicating that the model can simulate the hydrodynamic processes correctly. The results show that the thermal discharge is released along with the coast, the influenced extension in the downstream is larger than that in the upstream due to the effect of river runoff. During spring and neap tides the timeaveraged temperature rise near the waterspout of the project is 2.34 and 2.84 ℃, respectively; the areas with surface temperature rise 1.0 ℃ is 0.09 and 0.20 km2, respectively; and the areas with bottom temperature rise 1.0 ℃ are both 0.09 km2, respectively. The current speed is larger, the advection and lateral diffusion of water temperature is greater in spring tide, resulting in temperature rise near the waterspout of the project and its expand extent and magnitude along the coast is obvious smaller in spring tide than in neap tide.
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    Eco-hydrological functions of the evergreen broad-leaved forest litter and soil at different succession stages in Tiantong, Zhejiang
    SHEN Hui-tao;YOU Wen-hui;JIANG Yue
    2010, 2010 (6):  35-44. 
    Abstract ( 2937 )   PDF (1022KB) ( 1541 )   Save
    To study the ecohydrological functions of the litter and soil, we selected shrubland ( Lithocarpus glaber + Loropetalum chinense community), secondary and young evergreen broadleaved forest (EBLF) ( Schima superba community) and mature EBLF ( Castanopsis fargesii community) as research stands. The results showed that the storage of litter layer was as follows: Lithocarpus glaber + Loropetalum chinense community (6.66 t·hm-2)>mature Castanopsis fargesii community (6.43 t·hm-2) > Schima superba community (6.1 t·hm-2). The water holding capacity in mature EBLF, secondary and young EBLF, shrubs were 10.58,11.29 and 13.88 t·hm-2, and the corresponding effective water holding depth of litter layer in these three types were 0.49,0.55 and 0.73 mm respectively. During the process in water holding of litter layer, the water holding capacity and absorption speed in the first 2 hours were superior to the rest of time. The equations of water holding capacity and water absorption speed with immersed time are Q=alnt+b and V=ktn . Compared with Castanopsis fargesii community and Schima superba community, the physical properties and water holding capacity of soil of Lithocarpus glaber + Loropetalum chinense community didn’t drop behind the other two types of forests. During the studying period, the water storage of three forest soil within the depth of 30 cm was 67.2~150.0 mm. These results suggested that the soil layer had a better water holding capacity than that of the litter layer in different types of the forest.
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    Study on start-up of anaerobic ammonia oxidation reactors with different inocula
    LIN Jian-bo;GENG Liang;CHEN Yu-xia;HUANG Min-sheng;HE Yan;ZHU Yong
    2010, 2010 (6):  45-53. 
    Abstract ( 2426 )   PDF (3208KB) ( 1726 )   Save
    Three different mixed sludges, including anaerobic granular sludge and aerobic activate sludge, river sediments and aerobic activate sludge, anaerobic digested sludge and aerobic activate sludge, were used as inocula in three parallel SBR systems treating typical municipal wastewater, respectively. It was found that the anaerobic ammonia oxidation (ANAMMOX)reactors could be successfully startedup after 150~180 days’ operation with the NH4+-N removal efficiencies of 88%, 80% and 85%, respectively. Moreover, all the NO2--N removal efficiencies of these reactors were more than 96%. Comparatively, the startup period of the seeding sludges, namely the mixed anaerobic digested sludge and aerobic activate sludge,was relatively the shortest. Therefore, the above mixed sludge can be considered a promising inoculum for the start-up of AMAMMOX reactor.
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    Preliminary study on spatial and temporal variations of phytoplankton community in Lake Dianshan
    YANG Hong;WANG Yi-pin;BO Fang-fang;JIANG Yue;YOU Wen-hui;
    2010, 2010 (6):  54-63. 
    Abstract ( 2979 )   PDF (1513KB) ( 1989 )   Save
    In order to evaluate the spatial and temporal variations of phytoplankton community structure in Lake Dianshan, an investigation was carried out from October 2008(autumn) to September 2009 (summer). Total of 384 species were identified. The phytoplankton community was mainly composed by Chlorophyta , Cryptophyta , Cyanophyta and Bacillariophyta . In quantity, the dominated species were Chroomonas acuta , Chlorella vulgaris all year round and Microcystis in summer. The average density of phytoplankton was 4.01×106 cells·L-1, in the order from large to small was: summer, spring, winter and autumn.The ShannonWiener index, Margalef index and Pielou index were ranged from 0.31 to 1.59,2.22 to 7.98 and 0.17 to 0.82 respectively, which meant that both diversity and uniformity of phytoplankton were in healthy status in Lake Dianshan. The structure of phytoplankton was examined by the cluster analysis. The results was that the phytoplankton community can be separated into four groups. GroupⅠ(S3,S6,S7)was in the middle and southwest area, groupⅡ(S1,S2)in the east and southeast, group Ⅲ(S4,S5) in the north and west, groupⅣ (S8) in the south. Groups were classified by quantity and dominated species of phytoplankton. Historical data was also used to analysis the longterm variation of phytoplankton community.
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    Identification of wilt pathogens of potted Chongming narcissus(Narcissus tazetta var. chinensis)
    MA Tengfei;XU Zhen;FENG Linyan;LI Xiaofang;SUN Yue;XU Ling
    2010, 2010 (6):  64-71,8. 
    Abstract ( 2637 )   PDF (2266KB) ( 1424 )   Save
    Using morphologic characters and internal transcribed spacers (ITS) sequence analysis and Inter-simple-sequence -repeat(ISSR)markers, 3 isolates wilt pathogens in potted plant of Chongming narcissus were detected. One was Nectria gliocladioides , while other two were Fusarium moniliforme var. subglutinans . Pathogenic test resulted in that N.gliocladioides was the advantage pathogen, and its optimum growth temperature is 25 ℃. The hypha couldn’t growth while the temperature is lower than 5 ℃ or higher than 40 ℃. The study would be helpful to prevent and cure blight of Chongming narcissus potted plant. ISSR markers are useful for distinguishing the pathogen stains. It could be a molecular assistant means for identification of fungal and species.
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    Preliminary study on the metazoan zooplankton community structure of Fenshuijiang Reservoir and water quality assessment
    CHEN Liang;LIU Yi;YU Na;FENG Deng-xiang;LI Er-chao;JIA Yong-yi;CHEN Li-qiao
    2010, 2010 (6):  72-82. 
    Abstract ( 2771 )   PDF (1413KB) ( 1851 )   Save
    To provide basic information for further reservoir management and restoring, the community structure of zooplankton including species composition, biomass, density, diversity index and chemical and physical parameters were studied monthly in Fenshuijiang Reservoir of Zhejiang province from October 2008 to December 2008. A total of 23 zooplankton species were identified, including 11 Rotifera (48% of the total ), 6 Cladocera (26% of the total ) and 6 Copepoda (26% of the total ). The dominant species mainly were Keratella cochlearis, Asplanchna priodonta, Bosmina longirostris and Mesocyclops dissimilis during this period. The average density of zooplankton ranged 78.0~297.3 ind./L, and the average biomass ranged 2.044~8.924 mg/L in Fenshuijiang Reservoir. The results in this study indicate that the water quality of the Fenshuijiang Reservoir is between α and β type of medium pollution, based on the biological parameters including the qualitative and quantitative analyses of zooplankton community, biodiversity indexes and chemical parameters with integrated pollution index and chemical evaluation index. It was suggested that the further work should be carried out to strengthen the current reservoir ecosystem.
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    Morphology and morphogenesis of microtubular organelles in the cortex of Euplotes eurystomus(Ciliophora,Hypotrichida)
    SHENG Xin;WANG Zheng-jun;YIN Fei;GU Fu-kang
    2010, 2010 (6):  83-90. 
    Abstract ( 2886 )   PDF (2418KB) ( 1504 )   Save
    The cortical microtubular organelles of hypotrichous ciliate Euplotes eurystomus were visualized by using FLUTAX direct-fluorescent labeling. These organelles were composed of ciliature microtubules, ciliature baseassociated microtubules and cortical non-ciliated regions microtubules. The ciliature microtubule and ciliateure base-associated microtubule consists of adoral zone of membranelles(AZM) and membranelle brackets microtubules; undulating membrane(UM) and its base-associated microtubule nets; frontal-ventral-transverse-caudal-cirri (FVTCC), left marginal cirri (LMC) and the anterior longitudinal microtubules(ALM), posterior longitudinal microtubules(PLM),transverse microtubules(TM); the dorsal kineties (DK) and the rosette-like skeletal structure. The cortical non-ciliated regions microtubule comprises leptos microtubule nets in the dorsal and ventral cortex; the oblique microtubules in the dorsal cortex; and the longitudinal microtubules. During the process of the morphogenesis of the ciliatures, the AZM of proter is generated from the old AZM. The old ciliature base-associated microtubules degenerate as the FVTCC of proter and opisthe morphogenesis and differentiate. The old cirri and its associated microtubules might play a role of orientation and localization, but without direct physical contribution. The results provide data for the understanding of the construction of cortical microtubular organelles, the differentiation of cortical microtubules and the regulation of cell in ciliates.
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    Analysis on biological composition and food-chain structure in the urban rivers of Shanghai
    YU Na;LIU Yi;JIANG Xue-qin;XIONG Ze-quan;MAO Kai-yun;DAI Qi;LI Er-chao;CHEN Li-qiao
    2010, 2010 (6):  91-100,. 
    Abstract ( 3166 )   PDF (729KB) ( 2046 )   Save
    The community structure, biodiversity and dominant species of the four urban rivers in Shanghai (Caoyanghuanbang River, Henggang River, Wuchaogang River and Chaoyang River) were investigated during the period of Nov. 2007 to Oct. 2008. Totally, 268 species of phytoplankton, 157 species of zooplankton, 21 speices of macrobenthos, 10 speices of higher plants and 13 speices of fish were identified. In phytoplankton, Chlorophyta, Euglenophyta, Bacillariophyta, Cyanophyta had the highest richness. There were 94 species of protozoan, 44 species of rotiferan, 13 species of cladoceran and 6 species of copepodan in the zooplankton group; the macrobenthos included 14 mollusks, 3 annelidans, 2 crustaceans and 2 insect larvaes; fishes belonged to 7 families in which Cyprinidae was the most abundant species (53.8%). Higher plants included 4 species of submerged plants, 4 species of emerged plants and 2 species of floating plants. The biodiversity of phytoplankton, zooplankton, macrobenthos, fish and higher plants were much higher in Caoyanghuanbang River than the other three, and there was no dominant species for each group, and vegetation was of high density and mainly was emergedplants. While, in Henggang River, the biodiversity of phytoplankton was the lowest and mosquitoeating fish was the only vertebrate species, the most abundant plant was the submerged species. The biomass in Wuchaogang River and Chaoyang River was the lowest among the four rivers in which the dominant species of phytoplankton were Cyanophyta and Chlorophyta. The four rivers were all identified as having simplified food webs based on the analysis of the community composition and distribution of the dominant species. Further suggestions were made that the process of ecological restoration should be different due to the different bioticcomponenttypes of rivers with the aim of enhancing the community structure and the foodchain construction.
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    Effects of auxins on the propagation of Asparagus officinalis L.
    WANG Jingyu;ZHANG Xueping;YANG Ru;LI Xiaofang
    2010, 2010 (6):  101-108. 
    Abstract ( 2945 )   PDF (5198KB) ( 1797 )   Save
    The roles of auxin played in the propagation of asparagus were studied. Exogenous auxin was necessary for the formation of calli, while it wasn’t necessary during proliferation of shoots. The best induction of shoots was achieved with 0.05 mg/L NAA, and more calli induction needed over 1.0 mg/L NAA. The concentration of NAA in the regeneration of shoots hadn’t further influence on rooting. Comparing the four sorts of auxins, NAA, IAA, IBA and 2, 4-D during roots induction of asparagus, IBA is the best choice both in the quality and rate of rooting.
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    Investigation on morphogenesis of slug during Dictyostelium discoideum development
    LI Li;WANG Da-lei;HOU Lian-sheng
    2010, 2010 (6):  109-115. 
    Abstract ( 2572 )   PDF (1995KB) ( 1603 )   Save
    The characters of cell differentiation and cell apoptosis of Dictyostelium discoideum , especially slug, were studied by Acridine orange and Hoechst 33342 staining, two vital fluorescence dyes, with the help of fluorescence microscopy. The results show that different degree apoptosis of the pre-stalk cells during development were referred to the colors, blue-green, green, orange, and finally colorless. In the later of slug stage, a channel-like structure were observed. These data indicate that slug is the initiation phase of cell differentiation and recessionary in Dictyostelium discoideum. Furthermore, the morphological characters change greatly during the slug stage. The pre-stalk cells have already initiated apoptosis since the early stage of slug period. However, their apoptosis is a gradual process.
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    Key technologies in a super large panel autostereoscopicdisplay system
    TIAN Feng;YU Lei;LIU Jin-gao
    2010, 2010 (6):  116-124. 
    Abstract ( 2330 )   PDF (2836KB) ( 1364 )   Save
    To obtain a low cost super large panel auto-stereoscopic display system, 3D monitor based on DLP was proposed. Optical transmission property of lenticular lens was analyzed. By simulating light path of lens, the figure of stereo viewing zones was obtained. With the crosstalk of stereo viewing zones, the parameters of lenticular lens suitable for large panel auto-stereoscopic display were deduced. For the best observing distance, the relationship between virtual cameras' distance and the scene limit positions was analyzed. An about 150-inch-large panel stereo display wall with enhanced three-dimensional effect and telepresence of the monitor at the same time was made.
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    Automated derivation for analytical approximate solutions to nonlinear differential equations
    CHU Hong-mei;LIU Ying;LIU Yin-ping
    2010, 2010 (6):  125-136. 
    Abstract ( 2884 )   PDF (697KB) ( 1580 )   Save
    Based on four kinds of Adomian polynomials algorithms proposed by R. C. Rach, a package NAPA was developed on Maple 12. The interface of NAPA is user-friendly. As long as one input a differential system with boundary or initial conditions, NAPA can entirely automatically output more accurate approximating solutions. Finally, two different type of examples were given to demonstrate the effectiveness of the package.
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    Weighted graphs permitting no LEW-embeddings
    CAO Ni; LIU Ni; REN Han
    2010, 2010 (6):  137-141. 
    Abstract ( 2777 )   PDF (291KB) ( 1302 )   Save
    This article studied the LEW (large edge width) embeddability of weighted grid graph G(a,b)(a≥2,b≥2) and the Mobius ladder graph Gn(n≥4) and showed that such two types of weighted graphs have no LEW-embeddings. Based on these two kinds of graphs weighted graphs were constructed which are strongly embedded in Sn and Nh and permit no LEW-embeddings in the same surface they embedded.
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    Isomorphism of transformation graph
    GU Xiu-song;XU Dan-dan;SUN Zhi-ren;YAO Ze-qing
    2010, 2010 (6):  142-145,. 
    Abstract ( 2558 )   PDF (296KB) ( 1284 )   Save
    By the method of degree sequence, It was shown that G--+ is isomorphic to Hn--+ if and only if G is isomorphic to Hn. It was also shown that for a grap G, when G is connected, then G--+ and Cn--+ are isomorphic if and only if G and Cn are isomorphic.
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    Applications of axiomatic capital allocation and generalized weighted allocation
    HU Feng-xia;YAO Ding-jun
    2010, 2010 (6):  146-155. 
    Abstract ( 2643 )   PDF (198KB) ( 1607 )   Save
    Applications of two kinds of capital allocation principles were studied: one was axiomatic allocation which had been known, and the other was generalized weighted allocation. Firstly, several known risk measures were listed. Based on a axiomatic method, allocation formulae with respect to these risk measures were given. Then in view of a specific numerical model, its allocation results were calculated. Secondly, generalized weighted allocation, which was an extension of weighted allocation, was considered. A method for comparing the amounts of generalized weighted capital allocations under two different aggregate losses, which stems from diversifying property, was mainly discussed. And some special examples were given.
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    Multidimensional credibility models with random common effects
    ZHANG Yi; WEN Li-min;
    2010, 2010 (6):  156-168. 
    Abstract ( 2453 )   PDF (218KB) ( 1561 )   Save
    Multidimensional credibility models with a random common effect were built, and the inhomogeneous and homogeneous credibility estimators were derived. Further, some properties of these estimators were presented. Analogy to the classical credibility theory, the multidimensional credibility estimators with the common effect can also be expressed as the weighted sum of individual mean, collective mean and collective premium, where these weights are so-called credibility factor matrices. Finally, a numerical example
    was given to show the calculations of multidimensional credibility estimators.
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    Pricing basket future options in jump-diffusion models
    JIANG Ying;LIN Jian-zhong
    2010, 2010 (6):  169-177. 
    Abstract ( 2677 )   PDF (303KB) ( 1560 )   Save
    A model of future market in which the prices of k futures are governed by a m-dimensional Brownian motion and a l-dimensional Poisson process is considered. Applying the forward martingale measure method, the Black-Scholes pricing formula for an European basket future option is obtained.
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    Existence of positive periodic solution for a kind of predator-prey systems
    LIU Xing-bo;HE Liu-rong
    2010, 2010 (6):  178-185,. 
    Abstract ( 2465 )   PDF (212KB) ( 1386 )   Save
    A non-autonomous predator--prey diffusive system of three species with delay was analyzed. By using Gaines and Mawhin's continuation theorem of coincidence degree theory, some sufficient conditions for the existence of positive periodic solution were established for the system.
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    Hopf bifurcation analysis of a predator-prey system with delay and harvesting
    RAO Feng;WANG Wei-ming;LI Zhi-bin
    2010, 2010 (6):  186-198. 
    Abstract ( 2866 )   PDF (252KB) ( 1585 )   Save
    In this paper, by using the analysis of qualitative method and bifurcation theory, we investigated the dynamics of the Monod-Haldane type predator-prey system with constant prey harvesting and a single time delay. It is shown that the Hopf bifurcation can occur as the delay τ crosses some critical values. Furthermore, the direction and stability of the Hopf bifurcation are determined by deriving normal form theory and center manifold theorem. Finally, numerical simulations are performed to illustrate the analytical results.
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