Table of Content

    25 May 2016, Volume 2016 Issue 3 Previous Issue    Next Issue
    For Selected: Toggle Thumbnails
    A linear compact scheme for the nonlinear Schr"odinger equation with wave operator
    LI Xin, ZHANG Lu-Ming, CHAI Guang-Ying,
    2016, 2016 (3):  1-8.  doi: 2016.03.001
    Abstract ( 1235 )   HTML ( 10 )   PDF (363KB) ( 2973 )   Save
    In this paper, a linear compact finite difference scheme is proposed for the nonlinear Schr"odinger equation with wave operator (NLSEWO). Thus, the periodic initial value problem of the NLSEWO is solved. The unconditional stability and convergence in maximum norm with order O(h[4]+tau[2]) are proved by the prior estimations and the energy method. Those theoretical results are demonstrated by a numerical experiment.
    References | Related Articles | Metrics
    High order interpolation function for surface contact problem
    FENG Yun-Qing, HOU Lei
    2016, 2016 (3):  9-20.  doi: 2016.03.002
    Abstract ( 1176 )   HTML ( 72 )   PDF (1924KB) ( 2712 )   Save
    This paper mainly adopts Lagrange bicubic shape function to construct interpolation function and uses finite element method to solve the coupling equations of surface contact. The Lobatto points are used to construct the interpolation nodes to avoid the Runge phenomenon. Higher shape functions and  two different numerical integration methods are adopted to improve the accuracy of the numerical solution. According to the above analysis, this article uses Matlab program to simulate the deformation and stress changes in surface contact problem.
    References | Related Articles | Metrics
    vec  estimates of solutions to the Cauchy problem of[2mm] one-dimensional convection-diffusion equations
    ZENG Yan, XIN Gu-Yu
    2016, 2016 (3):  21-26.  doi: 2016.03.003
    Abstract ( 1263 )   HTML ( 10 )   PDF (250KB) ( 2591 )   Save
    This paper investigated the  estimates of solutions to one-dimensional convection-diffusion equations frac{partial c}{partial t}+ufrac{partial c}{partial x}=Dc_{xx}+c_{xt}-(c{2})_{x}, using Green's function method, frequency decomposition and energy estimates. We found that the decay rate of the solution is the same as that for heat fusion operator
    References | Related Articles | Metrics
    A class of singularly perturbed weakly nonlinear boundary\\[2mm] value problems with interface conditions
    WU Cheng-Long
    2016, 2016 (3):  27-38.  doi: 2016.03.004
    Abstract ( 1234 )   HTML ( 7 )   PDF (284KB) ( 2482 )   Save
    In this paper we study a class of weakly nonlinear boundary value problems with interface conditions. By means of the Schauder fixed point theorem we establish the theorem about a weakly nonlinear boundary value problem with interface conditions. By the method of boundary layer function, the formal asymptotic solution is constructed, which is used to prove the existence of the solution
    References | Related Articles | Metrics
    Bogdanov-Takens bifurcation for a delayed predator prey system with stage structure
    LIU Xia, JIAO Jian-Feng
    2016, 2016 (3):  39-47.  doi: 2016.03.005
    Abstract ( 1231 )   HTML ( 8 )   PDF (294KB) ( 2444 )   Save
    In this paper the Bogdanov-Takens (BT) bifurcation of a delayed predator prey system with stage structure and constant harvesting is considered. The existing conditions which guarantee an interior equilibrium of the system is BT singularity are obtained and the corresponding normal form for the system at this singularity is presented, some bifurcation results are shown
    References | Related Articles | Metrics
    Quasi-stationary distributions for absorbing stochastically monotone Markov chains
    ZHU Yi-Xia
    2016, 2016 (3):  48-59.  doi: 2016.03.006
    Abstract ( 1276 )   HTML ( 9 )   PDF (240KB) ( 2547 )   Save
    In this paper, we prove some limit theorems for absorbing stochastically monotone Markov chain during its lifetime. The emphases are on the stationary conditional, doubly limiting conditional and limiting conditional mean ratio quasi-stationary distributions. We study the uniqueness and domain of attraction of
    three types of quasi-stationary distributions for stochastically monotone Markov chains. A sufficient condition for the uniqueness of the three types of quasi-stationary distributions is given in our main results and under this condition, the unique quasi-stationary distribution attracts all initial distributions. We apply the main results to birth and death processes.
    References | Related Articles | Metrics
    Improved collaborative filtering algorithm based on usersimilarity
    WANG Wei, ZHENG Jun
    2016, 2016 (3):  60-66.  doi: 10.3969/j.issn.1000-5641.2016.03.007
    Abstract ( 1480 )   HTML ( 647 )   PDF (1219KB) ( 4268 )   Save
    Collaborative filtering is widely accepted and applied currently as one of the most popular personalized recommendation methods. It is an implementation method based on content that has considerable advantages in accuracy. The core issue of collaborative filtering is how to work out the calculation of similarity. In this paper, we introduce the traditional collaborative filtering algorithm and make similarity calculation more accurately by optimizing the traditional formula of similarity. Experimental results show that the optimized algorithm can improve the accuracy of the recommendation and reduce the MAE (Mean Absolute Error, MAE) efficiently.
    References | Related Articles | Metrics
    One-loop analysis of nucleon-nucleon scattering in the chiral effective field theory
    LI Fan, YANG Ji-Feng
    2016, 2016 (3):  67-75.  doi: 2016.03.008
    Abstract ( 1177 )   HTML ( 6 )   PDF (384KB) ( 2481 )   Save
    In this paper we will analyze the important one-loop pion-exchange diagrams for nucleon-nucleon (N-N) scattering in the relativistic framework of chiral effective theory, namely the triangle diagrams and the planar box diagram. On this basis, we wish to further explore the structures of the chiral effective theory in order to contribute to the establishment of a satisfactory effective field theory for nuclear forces
    References | Related Articles | Metrics
    SIM(2) gravitational gauge theory
    WU Yi-Wei, XUE Xun
    2016, 2016 (3):  76-83.  doi: 2016.03.009
    Abstract ( 1305 )   HTML ( 6 )   PDF (293KB) ( 2417 )   Save
    Based on the anisotropies of CMB (Cosmic Microwave Background Radiation, CMB) on the large scale and Mach's principle,this paper proposed that the Lorentz invariance is violated from the length scale of galaxy. SIM(2) gauge theory was taken as an example of such motivation to illustrate the so called dark matter effect,the deviation of astronomical observation from Newton-Einstein prediction, which can be emerged from the accumulated Lorentz violation effect on the short scale. SIM(2) gauge theory was analyzed and 8 additional constrain equations were obtained in addition to the equation of motion, while the independent components of contorsion were also reduced to 8. It can lead us to the conclusion that the contorsion is non-trivial and can contribute an
    effective energy-momentum distribution even in the region devoid of matter. Finally, the cylindrical symmetrized solution of metric under weak field expansion was given and its property was analyzed.
    References | Related Articles | Metrics
    Performance optimization scheme for a novel cooperation spectrum sensing system
    ZENG Ying, LI Zhi-Yong, ZHANG Chun-Ping, TANG Jing-Min-
    2016, 2016 (3):  84-91.  doi: 10.3969/j.issn.1000-5641.2016.03.010
    Abstract ( 1307 )   HTML ( 6 )   PDF (2244KB) ( 2439 )   Save
    In order to reduce effect of hidden terminal on cognitive system performance and the error rate of perceived system, it is proposed that, under the condition of considering wireless Rayleigh fading channel and reported channel with a fixed error probability, joint optimize index p of p power detector, optimal sensing threshold λand the best number of cooperative users K on multiple antenna sensing system with p power detector to minimize the total error probability. Theoretical analysis and simulation results show that cooperative spectrum sensing system has the best index p* and the best perception threshold λ*, and when choosing a fusion rule it can improve the reliability for sensing system by choosing appropriate cooperative users K.
    References | Related Articles | Metrics
    Comparative analysis of microbial communities on tobacco leaves  between clone library and highthroughput sequencing
    GONG Jun, LIU Yu-Pei, LI Yuan-Yuan-
    2016, 2016 (3):  92-101.  doi: 10.3969/j.issn.1000-5641.2016.03.011
    Abstract ( 1325 )   HTML ( 7 )   PDF (1243KB) ( 2471 )   Save
    In order to compare the microbial communities on tobacco leaves between clone library method and highthroughput sequencing method, we analyzed the diversity of microbial communities based on bacterial 16S rDNA and fungal ITS on tobacco leaves collected from Fujian province in China. The results showed that more numbers of bacterial and fungal sequences were detected by highthroughput sequencing than clone library. The number of operational taxonomic units (OTUs) clustered from highthroughput sequencing method was almost the same as that from clone library method in bacterial communities, while that was higher from highthroughput sequencing in fungal communities. The rarefaction curves drawn from highthroughput sequencing method tended to approach the saturation plateau. The expected community diversity indices (Chao1 and Ace) were higher in clone library method, whereas the observed community diversity indices (Simpson and Shannon) suggested that higher bacterial diversities were detected through clone library method and higher fungal diversities were detected through highthroughput sequencing method. There were more kinds of bacteria and fungi genera identified through highthroughput sequencing method. The dominant genera of bacteria were similar detected from both of the methods, including Pseudomonas, Acinetobacter and Sphingonomonas. However, the fungal genera detected through these two methods were significantly different. Overall, novel highthroughput sequencing methods outperform clone library approaches in terms of resolution and magnitude. They enable identification and relative quantification of community members of tobacco leaves and offer new insights into environmental microbiology. 
    References | Related Articles | Metrics
    Extracellular ATP affects the copper–induced cell death and H2O2 production in tobacco (Nicotiana tabacum L) cell-suspension cultures
    BAI Jing-Yue, FENG Han-Qing, GUAN Dong-Dong, SUN Kun, JIA Ling-Yun, LI Qiao-Xia, ZHANG Jin-Ping
    2016, 2016 (3):  102-114.  doi: 2016.03.012
    Abstract ( 1123 )   HTML ( 6 )   PDF (610KB) ( 2310 )   Save
    Extracellular ATP (eATP) has been considered as a mediating signal in several physiological processes of plants. In this article we showed that eATP can affect the copper-induced cell death and hydrogen peroxide (H_{2}O_{2}) production. CuCl_{2} at concentrations from 100 to 700 textit{mu }molL caused a
    significant increase of cell death in tobacco (textit{Nicotiana tabacum} L) suspension cultures, and this increase of cell death level was followed with increases of both intracellular and extracellular H_{2}O_{2} production. The cells exposed to 300 textit{mu }molL CuCl_{2} were chosen to investigate the mechanisms for the copper-induced increases of cell death and H_{2}O_{2} production and the effect on this process. The results showed that the treatment_{ }with CuCl_{2 } at this concentration increased the activity of NADPH oxidase, and addition of DPI (diphenylene iodonium, an inhibitor of NADPH oxidase)alleviated the CuCl_{2}-induced increases of cell death and H_{2}O_{2} production, indicating that the CuCl_{2}-induced increases of cell death and H_{2}O_{2} production were related to an increase of the activity of NADPH oxidase. Addition of exogenous ATP at 50 textit{mu }molL into the CuCl_{2}-stressed cells further enhanced the levels of cell death,H_{2}O_{2} production, and NADPH oxidase activity. However, in the presence of DPI, exogenous ATP failed to do so. These observations indicated that eATP can affect the copper-induced changes of cell viability and H_{2}O_{2} production bystimulating NADPH oxidase
    References | Related Articles | Metrics
    Spatial evolution of science and technology innovation gravity center and its factors in China from 1996 to 2012: An analysis based on provincial data
    LI Heng, DU De-Bin, XIAO Gang
    2016, 2016 (3):  115-124.  doi: 2016.03.013
    Abstract ( 1013 )   HTML ( 10 )   PDF (927KB) ( 2092 )   Save
    Regional science and technology (ST) innovation capacity plays an increasingly important role in regional socioeconomic development. On the base of current research, we introduced gravity center model to the regional differences research of China ST innovation and work out ST innovation gravity center and its evolution characteristics in the period of 1996-2012. We summarize the main factors which drive the evolution of ST innovation gravity center by comparative analysis and quantitative study. The results are showed as follows. The ST innovation gravity center has been moving quickly to the southeast direction in the past 16 years, and departure increasingly from the geometric center of China. There is a strong correlation between ST innovation gravity center and economic gravity center and Hi-tech Industry gravity center and RD investment gravity center. The main driving factors of China ST innovation gravity center movement consist of economic structure and growth mode,agglomeration of ST resources and ST innovation environment.
    References | Related Articles | Metrics
    Potential hazard assessment of typhoon storm surge based on scenario simulation methodology in Yuhuan County, Zhejiang Province
    CHEN Jie, SONG Cheng-Cheng, LI Meng-Ya, WANG Jun-
    2016, 2016 (3):  125-135.  doi: 10.3969/j.issn.1000-5641.2016.03.014
    Abstract ( 1243 )   HTML ( 17 )   PDF (5726KB) ( 2531 )   Save
    Typhoon storm surges are responsible for most of the damage caused by oceanic disasters in Yuhuan, Zhejiang Province. Considering the coastline features of Yuhuan County, 7 translation paths were designed based on the path of TC0608 (Saomai), which formed the lowest central pressure at the moment of landfall in Zhejiang since 1949. In consideration of the 7 translation typhoon paths and sea level rise, storm surges in 28 compound scenarios were simulated by using MIKE21 FM for potential impacts analysis. The results showed that the possibility of overtopping inundation due to typhoon storm surges was quite low under the present condition. However, the impacts obviously became more serious as sea level rising, and the three typhoons landing in the north of Yuhuan were especially sensitive in terms of responding to the sea level rose. In scenarios with the same sea level rise value, typhoons landing in the south of Yuhuan caused more serious inundation than those landing in the north part. In 2100, the largest water depth would reach 5.44 m and the inundation area would be 160.75 km2, accounting for about 35.93% of the total area of Yuhuan. The potential highrisk inundation areas are mainly distributed in the southeastern and western part of Yuhuan, with a relatively low elevation. The results could offer reference for making adaptation strategies and engineering countermeasures for future extreme storm surges disasters in Yuhuan County.
    References | Related Articles | Metrics
    Water and sediment transport mechanism in the Huangpu River Estuary, Shanghai
    SONG Yong-Gang, LU Yong-Jin, LIU Xin-Cheng-
    2016, 2016 (3):  136-145.  doi: 10.3969/j.issn.1000-5641.2016.03.015
    Abstract ( 1100 )   HTML ( 6 )   PDF (1815KB) ( 2224 )   Save
    Sediment transports in a bend channel affected by the tide are different from those dominated by the riverine flow. This paper used the flux decomposition mechanism method to examine the water and sediment transports in the Huangpu River Estuary, basing on the field observations in the 2002 flood season. The results showed that the water and sediment transports in the Huangpu River Estuary consisted of longitudinal and transversetransportsinduced by the secondary flow.The net water transport averaged over a tidal cycle points to the ebb direction, and the net sediment transport points to upstream dominated by the tidal pumping effect. The net transport of both water and sediment across the channel over a tidal cycle direct to the convex bank, in which an Euler transport predominated in water transport, and an advection transport controled sediment transport.Compared the longitudinal with the transverse water and sediment transport fluxes, we found that the crosschannel net water transports were bigger than alongchannel fluxes over a flood tidal cycle while crosschannel sediment transport fluxes were smaller than alongchannel fluxes, which implied that the tidal pumping played the major role in the net transports of sediment in the flood season.
    References | Related Articles | Metrics
    In consideration of tidal condition to improve optical inversion algorithm on total suspended matters concentration according to in situ measurement in the Yangtze Estuary
    MA Hua, JIANG Xue-Zhong
    2016, 2016 (3):  146-155.  doi: 2016.03.016
    Abstract ( 847 )   HTML ( 8 )   PDF (903KB) ( 1672 )   Save
    Due to the interaction between the river discharge and the tide, as well as the high suspended sediment concentration in the surface water, the optical property of the Yangtze Estuary waters is different from the open sea waters. In a single tidal cycle, the total suspended maters (TSM) concentration can reach 0.5~kg/m{3} or more during spring tide, while in neap tide the maximum TSM concentration is only 1/3 of the spring tides. High TSM concentrations and a greater variation in single tidal cycle make a lot of empirical inversion algorithm unavailable in this region. A new algorithm was developed in the Yangtze Estuary, named improved complex proxy TSM (ICPTSM) model to improve the complex proxy TSM model. Using in situ synchronous optical and TSM concentration data
    collected in the survey in May 2014, we analyze the characteristic of sediment concentration changing in the Yangtze Estuary associated within entire tidal cycle. Based on the original seven alternative bands, we introduce two alternative bands, 806~nm and 858 nm, as a supplement. We add a near-infrared peak area index as the fifth index to the complex proxy (CP). Linear relationship between the CP index and TSM concentration is improved into quadratic relationship. For water characteristics of different tidal conditions, individual ICPTSM models have been established. The results show that: ICPTSMmodel is adaptable in the Yangtze Estuary, distinction model toward spring and neap tidal have higher retrieval accuracy than unified model for a whole tide cycle, distinction model can better describe changes of water-leaving radiance, and TSM concentration changes in a tidal cycle
    Related Articles | Metrics