Table of Content

    25 January 2013, Volume 52 Issue 1
    Coupling Relaxation in Interstitial Solid Solution of Tantalum
    LIN Guocong; LIU Hui;DING Xidong;ZHANG Jinxiu
    2013, 52(1):  1-6. 
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    In this paper, for the internal friction data of tantalum with oxygen or nitrogen, curve fitting was made by using generalized Arrhenius relation, and the results were discussed. To obtain a selfinduced ordering temperature T C, curve fitting was made with T C replaced with T 0 in generalized Arrhenius relation. Selfinduced ordering temperature T C, preexponential τ0 and apparent activation free energyΔG were calculated basing on the criteria of the minimum of the standard difference (SD) of curve fitting. For the situation with low concentration of relaxation unit, ΔH is the interception of plot of T 0-ΔG where T 0  is nearby the T C. Then entropy change ΔS and factor τ′0 can be calculated. The resultes are those as following: (1T C is proportionate to the concentration of oxygen or nitrogen. This indicate that the the increase of oxygen or nitrogen in tantalum makes the coupling between oxygen or nitrogen increases, then makes T C  increase. (2)With the increase of oxygen or nitrogen in tantalum,T CΔS, which is the contribution of combination entropy, increases, then makes the apparent activation free energy ΔG decrease. (3) Factor τ′ is almost a constant for tantalum with oxygen. The result is selfconsistent with the condition that there is a same activation enthalpy ΔH in it. These indicate that in the concentration range of oxygen in this paper, the relaxation unit is the same individual coupling unit. (4) For the situation of nitrogen concentration less than 1.0%, the relaxation unit is the same individual coupling unit. The relaxation unit changes when the concentration of nitrogen increases more. There may be some relaxation unit pairs with weak coupling in it, which make ΔS increase.
    Secure Symmetric Encryption Scheme Based on Obfuscator
    YUAN Zheng; GONG Gaoxiang
    2013, 52(1):  7-11. 
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    An symmetric encryption scheme with dynamic key based on obfuscation of point functions with multibit output(MBPF)is presented.A MBPF obfuscator with fully-entropic security, implying virtual black-box property(VBB), can be used to construct semantically secure encryption schemes with wrong key detection for α(n-weak keys. The symmetric encryption scheme is just the fully-entropic security MBPF obfuscator, whose key is deduced by a sensitive function . The sensitive function with two inputs, one is a secret key and another is a random key,and thus output key is random. The symmetric encryption scheme is more secure and implement simple.
    Study of Intersection Control Mode Evaluation  Based on Environmental Effect
    LIU Yonghong; LIAO Hanbo;YU Zhi; CAI Ming
    2013, 52(1):  12-16. 
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    Transportation costs, energy costs and environmental costs were used as indicators for the development of comprehensive index evaluation model. Paramics and CMEM model were used as the basic tools for simulating the scenarios of different flow levels. Yield-regulated control mode, roundabout mode and signal control mode were simulated in each condition and evaluated respectively. The results show that the proportion of energy cost is the highest in the total economic cost,and the economic cost of yieldregulated control mode in low flow level is the lowest while the total cost of signal control mode is lower than the others in middle or high flow levels.
    Research of Identification Technology of Digital Modulated by Single Carrier and Multicarrier Based on Decision Theory Algorithm
    YANG Faquan; LI Zan; LUO Zhongliang
    2013, 52(1):  17-22. 
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    The characteristic parameter extraction and automatic identification technology of wireless digital signal modulated by single carrier and multicarrier based on decision theory algorithm are researched mainly and  then the decision classifier, the identification steps corresponding which suitable for single carrier and multicarrier digital modulation recognition are put forward.A phase folding algorithm to correct the influence of phase folding was first used in instantaneous phase extraction and the accuracy of characteristic parameters was improved. The simulation results show it has good recognition effect, the system is easy to realize and it has a broad prospect of application in the signal recognition.
    Nonlinear Numerical Investigations on the Steel Reinforced Concrete of #br# Distributed Steel Bar Core Section
    YE Mao; PI Yinpei;REN Min;LIU Airong; LI Yongyan
    2013, 52(1):  23-28. 
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    Because of the SRC column are difficult to construct and the high cost, the new SRC crosssection of distributed steel bar with low cost is proposed based on the principle of which the same core steel ratio.The two types columns has been validated similar mechanical properties by the preliminary tests, and more indepth study of the seismic performance of this new crosssection column is presented. Considering the nonlinearity of the materials and the appearance of P-Δ, analysis models of SRC of distributed steel bar core section with FEMs software are built. Parameters of axial compression ratio, the core steel ratio, the strength of concrete and core steel bar which influence the P-Δ curves, horizontal ultimate load and ductility coefficients were analyzed for further study of the new SRC section. The conclusion is as follows: the horizontal ultimate load of new SRC crosssection of distributed steel bar was obvious influenced by the axial compression ratio and strength of concrete and less affected by the core steel ratio and the strength of the core steel bar; ductility coefficients which was obvious influenced by many factors is a sensitive indicator.
    Double Glass Curtain Wall Heat Flow Thermal Simulation of Fluid Dynamics
    MAO Huonan,GE Hongfei,CHEN Hai, REN Qiu,LAN Fatong,LIU Peng,GUO Jinji
    2013, 52(1):  29-33. 
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    In the strong sun radiation condition, the heat flow and thermal efficiency of double glass curtain wall are significantly increased with the forced air flow (referred to as the strengthening heat flow). The three-dimensional hydrodynamic model and the boundary condition are established. Using software of FLUENT, the thermal simulation of airflow and strengthening heat flow are executed. Under three different conditions of open,closed and without shading louver, the temperature and velocity distribution diagram are drawn, and the cause of strengthening heat flow are analyzed. Finally, verification experiment are completed.
    Research on Adaptive Dynamic Fuzzy Neural Network #br# Algorithms with Gauss Activation Function and Eigenvalue #br# Decomposition Pruning Technologies
    HE Zhengfeng;ZHANG Defeng; SUN Yamin
    2013, 52(1):  34-39. 
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     A new algorithm,which uses D-FNN Gauss function as a network activation function and fuzzy membership function, is proposed. The algorithm obtains strong global mapping generalization ability and effectiveness in local refinement,and adopts eigenvalue decomposition pruning technology to enables more compact D-FNN structure to avoid the phenomenon of over fitting. Finally, the algorithm is confirmed through the Hermite polynomial approximation to approach ability of validity. The simulation results show that the eigenvalue decomposition of pruning techniques and Gauss activation function of D-FNN has good performance.
    The Existence and Multiplicity of Positive Solutions of Generalized p-Laplacian Boundary Value Problems
    BAI Dingyong;ZUO Minxian
    2013, 52(1):  40-44. 
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    A generalized p-Laplacian boundary value problem with a parameter is concerned. By using the fixed-point theorem in cones, some results of existence and multiplicity of positive solutions for the problem are established with the parameter belonging to corresponding explicit intervals. In the existed literatures about multiplicity of positive solutions, the nonlinear terms are usually required to be positive for all positive real numbers. This condition is relaxed in the present paper, more precisely, the nonlinear terms can vanish on some subset.
    The Hopf Bifurcation and Stability of Cooperate System with Rate Harvesting
    CHEN Hongbing
    2013, 52(1):  45-50. 
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    A cooperate model with Holling Ⅱ functional response is established. And, the stability of this model and the Hopf bifurcation is investigated. An example shows the feasibility of the results.
    On the Growth of Solutions of Higher Order Homogeneous Linear Differential Equations
    JIN Jin
    2013, 52(1):  51-54. 
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    The growth of solutions of higher order homogeneous linear differential equation
    f (k)+Ak-1(z)Pk-1(e z)f +…+A1(z)P1(ez)f +A0(z)P0(ez)f=0
    is investigated, where Aj(z)≠0(j=0,1,…,k-1) are entire functions,Pj(ez)(j=0,1,…,k-1) are nonconstant polynomials of ez without constant term, and deg P(z) is not equal to deg Q(z). It is showed that the order of growth of each nonzero solution of the above equations is infinite.
    A Nonparametric Estimate of Integrated Cross-Volatility
    LI Cuixia;GUO Erlin; BAO Meijuan
    2013, 52(1):  55-58. 
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    A nonparametric estimator is proposed for the class of integrated cross volatilities of the form∫ 10 f(Xt2tdt, where f is a continuous function,σ2s is the instantaneous cross volatility of continuous semimartingale X. Using “Realized Volatility”, the asymptotic properties, which include consistency and asymptotic normality are obtained. A studentized version has been given and this can be used to construct confidence interval and do hypothesis testing.
    Wiener-Hopf Integral Operators on Rn+
    XIE Peizhu;CAO Guangfu
    2013, 52(1):  59-62. 
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    The Wiener-Hopf integral operator on the upper half-space of Rn is defined, and its basic properties are studied.
    Mechanical Properties of r-PET/PP Blends Compatibilized by#br# PP-g-MA and Its Mixture
    WANG Chunguang; LIN Jingxin; ZHANG Zishou; MAI Kancheng
    2013, 52(1):  63-67. 
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    In order to develop PP blends with recycled polyethylene terephthalate (r-PET), the blends of r-PET with compatibilizer, r-PET/PP and compatibilized r-PET/PP blends were prepared. PP-g-MA and its mixture of POE-g-MA or EVA-g-MA with same functional group were used as compatibilizers. The tensile strength, flexural strength and modulus and impact strength of blends were characterized. The effect of compatibilizer and r-PET on mechanical properties of blends was studied. The results indicated that the mechanical properties of r-PET decreased by adding compatibilizer. But the tensile strength, flexural strength and modulus of iPP increased by introduction of r-PET, and the mechanical properties of r-PET/iPP blends increased by adding compatibilization of PP-g-MA further. The increased mechanical properties of uncompatibilized and compatibilized r-PET/iPP blends with increasing r-PET contents indicated the presence of reinforcement of r-PET in the iPP matrix. The r-PET/iPP blends with high strength and high toughness could be obtained by compatibilization of mixture of compatibilizers. Addition of POE-g-MA or EVA-g-MA increased the impact strength of PP-g-MA compatibilized r-PET/PP blends. The r-PET/PP blends with high performance could be obtained by compatibilization of mixture PP-g-MA and POE-g-MA.
    Support Vector Machine in Forecasting the Supply of College Graduates
    CHEN Xiaojuan,YAO Zheng an, HUANG Wei
    2013, 52(1):  68-73. 
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    Multiple linear regression, time sequence extrapolation method, Grey Prediction GM (1, 1) Model, support vector machine are used in forecasting the supply of college undergraduate graduates. Based on comparison, it is discovered that support vector machine is the most suitable model for forecasting the supply of college graduates.
    Synthesis of TiO2/graphene Oxide Composite Nanocrystals in Hydrothermal System
    YANG Junsong;ZHANG Hui; WANG Teng;ZHANG Shengyi
    2013, 52(1):  74-76. 
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    TiO2/graphene oxide nanocrystals with tetragonal structure were synthesized at 200 ℃ in a closed vessel consisting of an appropriate amount of the mixture solution containing Ti(OC4H9)4 and absolute ethanol, graphene oxide and distilled water for 12 h. The results of X-ray powder diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) indicated that TiO2/graphene oxide nanocrystal was made up of tetragonal structure TiO2 with diameter less than 160 nm and graphene oxide. The UV measurement result indicated that the TiO2/graphene oxide composite nanocrystal had a potential photoelectrochemical conversion property.
    Synthesis and Growth Mechanism of the HTlc-glutamate
    WU Jiansong;LIANG Haiqun;LING Zhixian
    2013, 52(1):  77-82. 
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    A hexagonal HTlc-glutamate was assembled via glycol-hydrothermal using MgCl2·6H2O,AlCl3·6H2O,glutamic acid as raw material and sodium hydroxide as precipitator. Samples were characterized by X-ray diffraction(XRD),scan electron microscope(SEM),IR,thenna1 analysis (TG DTA) and BET-N2 surface area measurements.The result indicated that HTlc-glutamate exhibited well-defined shape and obvious intercalated structure during the glycol-hydrothermal process. From the point of the model of anion coordination polyhedron growth units,the growth mechanism and morphology of the HTlc-glutamate was also studied. The result indicated that the growth morphology of HTlc-glutamate was consistent with the model. The HTlc-glutamate growth process included ① growth units incorporated to metal layers first, ② metal layers adsorbed glutamate and H2O, ③ growth units incorporated to layer compounds according. As a result, glycol played important role in bridging.
    High Cell Density Culture, Purification and Identification of Algicidal Components of An Indigenous Algicidal Bacteria L7
    YANG Lili;PAN Weibin;WEN Yong;CHEN Qun
    2013, 52(1):  83-88. 
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    Base on an indigenous algicidal bacteria L7, technical and process parameters for high cell density culture and the research and development of biological algicide were investigated. In the stage of high cell density culture, we selected the appropriate cell culture medium of bacteria L7 (carbon and nitrogen source are glucose+NH4Cl, C/N ratio is 3∶1, pH 7.5), bacterial load (3.1×107  cfu/mL), DO (30%(±10%)) and agitation speed (160(±10) r/min) through the setting of single factor experiment and orthogonal experiment, the application of shake flask and automatic fermentor. The process of purify and identify algicidal components of L7 included dialysis, gel chromatography, HPLC, MS and et al. Finally two algicidal components were received, the molecular weights were 588.2 and 365.0 respectively, and the algicidal effect of the latter one weas better.
    Investigation of Interaction Between γ-Cyclodextrin Alizarin Yellow R Clathrate Compound and DNA
    OU Lianglong;WANG Xingming
    2013, 52(1):  89-93. 
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    Under the condition of physiological environment at pH 7.4, the binding ratio nγ-CDnAYR =1∶1 and binding constant KΘf ,288.15K=1.69×105 L/mol were confirmed by mole ratio method and linear method. AO was used as molecule probe, and the interaction between γ-CD-AYR and herring-sperm DNA was studied by UV spectra, fluorescence spectra, thermodynamic method and viscosity method, etc. A series of thermodynamic data such as ΔrHmΘ=8.78×103 J/mol, ΔrGmΘ=-2.59×104 J/mol, ΔrSmΘ=116.45 J/(mol·K) were obtained, and ΔrSmΘ was the primary driven power of this interaction, the binding ratio was  nDNAnγ-CD-AYR =1∶2, the binding constants were K 288.15K= 3.10×104 L/mol, K 310.15K 4.02×104 L/mol. The interaction mode between γ-CD-AYR and herring-sperm DNA was an electrostatic interaction and part embedded intercalation.
    Masculinization by Temperature Control in Larvae Nile Tilapia, Oreochromis niloticus  L.
    CHEN Xinghan, LIU Xiaochun, MENG Zining, ZHANG Yong, YE Wei,LIN Haoran
    2013, 52(1):  94-99. 
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    The tilapia(Oreochromis spp.)is very important for fishery in China. China is the first in the amount of product and export of tilapia in the world every year. The period of tilapia’s maturation is very short. So the reproduction is very fast and waste a lot of energy. The style of mono-male cultivation can resolve the problems. In this paper, the researches have been concentrated on the male rates under different water temperature condition in larva Nile Tilapia(Oreochromis niloticus L.). The possibility of making mono-male by temperature controlling has been discussed from two aspects: the effective temperature and the disposal duration time. The larvae were treated from 7DPH. Two factors were considered: the water temperature(20 ℃, 28 ℃, 36 ℃)and the disposal duration time(7-14DPH, 7-21DPH, 7-28DPH). They were taken into account by orthogonal experimental design. The main results are as follows: at the aspect of getting monomale by temperature control, when the temperature is 36 ℃, the male rates in the three disposal duration(7-14DPH; 7-21DPH; 7-28DPH)are significant higher than the other treatment schemes(P<0.05),the male rates are 93.85%, 96.00% and 96.92% respectively. In order to evaluate the effects of masculinization, the growth rates and the survival rates have been studied too. When the treatment schemes (temperature + disposal duration time) are 36 ℃+7-14DPH, the AGR and survival rate are no significant difference with the Control Group(P>0.05). In general, the best treatment schemes are 36 ℃+7-14DPH, the average male rate is 93.85% and the highest male ratio is 96.96%. The growth rate and the survival rate in that treatment schemes are normal too.
    Effects of Starvation Stress on the Histological Structure of the #br# Digestive Organs for Juveniles of  Trachinotus ovatus
    OU Youjun, SU Hui, LI Jiaer, WANG Yongcui, LIU Rujian, CAO Shouhua
    2013, 52(1):  100-110. 
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    By using morphorlogy and paraffin section technique, effects of starvation stress on the histological structure of the digestive organs including esophagus, stomach, pyloric caecum, intestine and hepatopancreas and their characteristics of changes were investigated in 375 juveniles of Trachinotus ovatus starved for 0, 3, 6, 9 and 12 d respectively for the purpose of understanding the changes in morphorlogy and histology and capacity of tolerence under starvation. The histology results show that effects of the short time starvation within 3 d on the digestive system were of no significance, with starvation time injury began to occur in digestive organs. The damage to digestive organs was lesser from the 6 to 9th days after starvation, and on 12th days after starvation, severe damage were found. Lumen of digestive tract became narrow and thinning, the epithelial cell boundaries were blurred , epithelial falled off and fractured, and secretory cells bacame smaller in size. Damage of histological structure in esophagus by starvation were minor compared with other organs. The effects of starvation were similar about the histological structure of the stomach, pyloric caeca and intestinal tract. Severer damage were found in hepatopancreas than other organs. In conclusion changes to varying degrees took place in digestive organs of juveniles of Trachinotus ovatus by starvation, and effect of starvation on differenct organs varied as time.
    Molecular Cloning, Sequence Analysis and Tissue Expression of Three Forms Trypsinogens in Zebrafish, Danio rerio
    CHEN Wenbo;LI Weiguo;ZHANG Zhen;JIAO Chunlei;WU Fan
    2013, 52(1):  111-117. 
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    Trypsin, one member of the serine protease family, plays important roles in animal protein digestion. It is synthesized and secreted as proenzyme trypsinogen, and removed the N-terminal activation peptide by enterokinase converting to active form in the intestine. The active trypsin can specifically cleavage at the peptide bond on the carboxyl side of basic L-amino acids such as arginine or lysine residuse. For studying the protein structure and physiological funtions of trypsinogen in fish, we successfully got three trypsinogen cDNAs (zftry1a、zftry1b and zftry2) from zebrafish by RT-PCR and RACE. The results showed zftry1a and zftry1b consisted of 242 amino acids which contained a signal peptide(SP) of 15 amino acids and an activation peptide(AP) of five amino acids, LDDDK. zftry2 consisted of 247 amino acids which contained a SP of 15 amino acids and an AP of nine amino acids, APLGDDDDK. The alignment based on the amino acid sequences revealed that they had the conversed structural characteristics, such as the catalytic triad (His-57, Asp-102, and Ser-195), 12 cysteines forming 6 disulfide bonds, Asp-189 at the bottom of the substrate-binding pocket and Gly-216 and Gly-226 lining the sides of the binding pocket, and so on. The results from isoelectric and phylogenetic analyses suggested that zftry1a and zftry1b were group with teleost anionic trypsinogen group I, while zftry2 was phylogenetically related to teleost cationic group II. Tissue expression pattern was similar to each other, and all trypsinogens were mainly expressed in the intestine. These results from zebrafish trypsinogens can provide the foundations for further study of its expression profiles, the molecular characteristics and evolution of fish trypsinogen.
    Application Studies on High Activity β-Glucosidase Producing Strain
    LIANG Cuiyi; XU Jingliang; YUAN Zhenhong; ZHANG Yu;XU Huijuan;ZHUANG Xinshu; GAO Yueshu
    2013, 52(1):  118-122. 
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    Studies of β-glucosidase enzymatic properties from Hypocrea sp. W63 show that, enzyme activity determined by pNPG (4-nitrophenyl β-D-glucopyranoside) can attain to 482.1 U/mL. The optimum reaction pH value and temperature are 4.8 and 65 ℃, respectively. 10% of ethanol has the greatest promotion, the β-glucosidase activity can nearly increased double and the ethanol tolerance of β-glucosidase can attain to 30%. When simultaneous saccharification and fermentation(SSF) carried out for 120 h with β-glucosidase adjunction, 41.25 g/L of ethanol can be obtained. Compared with control, the ethanol production can increase nearly 2-fold. The β-glucosidase with high enzyme activity, thermostable and alcohol tolerance for SSF application, indicate that the β-glucosidase producing strain has great potent application on cellulosic ethanol production.
    Study on Gradient Variation of Landscape Change in Zhuhai City Based on RS
    YANG Yipeng;SUN Haoming;GUO Luo ; DING Chao
    2013, 52(1):  123-129. 
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    Based on the RS images, survey and statistic data of the study area, 17 radiatively circular bands and 2 spatial samples were built starting from central area with the support of GIS. The spatial pattern, variation of landscape gradient and urbanization effect were analyzed by using landscape pattern indexes with remote sensing images and spatial gradient statistical analysis. The results indicated that landscape structure complexity and fragmentation in Zhuhai urban area gradually increased. The area of urban building, road and forest increased obviously, while the area of farm, bare land, water, shrub and beaches decreased. The change of landscape pattern showed that urbanization effect enlarged. With the movement of spatial sample from centre to urban fringe, the area of farm increased and urban building decreased gradually. The gradient directions of urbanization were obvious. Natural environment and human disturbance influenced the temporal and spatial landscape patterns Duing the past 15 years, the urban area of Zhuhai has extended 10 km to the northwest and 12 km to the southwest. With the study of spatial gradient, we can quantitatively analyse urban gradient expansion and structure change. The research is significant for urban planning and resources protection.
    Euclidean Distance Transform by Raster Scan in Obstacle Space
    ZHANG Qingnian
    2013, 52(1):  130-135. 
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    An algorithm of Euclidean distance transform was proposed by raster scan in obstacle space. It propagates distances line by line, checking the visibility of target pixels, and calculating the distance by finding a shortest way from a source to the target keeping away from obstacles. The algorithm is straightforward for distance calculation, involving in no complicated data structure, and having a linear computational complexity. Case study showed that the calculated distances by this algorithm were accurate, better than the results by the distance accumulationbased algorithm, and suitable for sources and obstacles in any types of shapes, including point, line and area objects.
    Researches on DFA-based Extreme Precipitation Threshold in the Pearl River Basin
    LIU Bingjun;WU LiLi; LU Wenxiu
    2013, 52(1):  136-141. 
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    Extreme precipitation events occur rarely and are difficult to collect samples. There are still uncertainty problems with the definition of extreme precipitation threshold, which is variable and not unified. This study summarizes the uncertainties of extreme precipitation threshold based on Fixed Critical Value Method, Special Percentile Value Method and the Goodness of Extreme Value Distribution Fitting Test. In order to overcome these problems, a new method,named as DFA, has been used to discuss the physical mechanism and applicable conditions. The system dynamics-based DFA, tracks extreme precipitation threshold by analyzing the characteristics of long range correlation of the precipitation series and can well reflect the statistical effects and scientific background of precipitation series.It is applicable to define extreme precipitation threshold within a basin.
    Mechanism of River Electrical Conductivity in the Dongjiang River Basin
    LI Shanchi;ZHENG Xiongbo;GAO Quanzhou;TAO Zhen; XIE Chenji;LIU Longhai
    2013, 52(1):  142-146. 
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    Based on the hydrochemical data of water samples from the Dongjiang River Basin in dry and wet seasons, the mechanism of river electrical conductivity (EC) is considered. The results show that EC in the Dongjiang River Basin is 85.3 μS/cm in January and 87.7 μS/cm in July. The share of weathering conductivity (Cw), seasalt conductivity (Cs) and anthropogenic conductivity (Ch) is 46.4%, 19.6% and 33.9% respectively. It indicates that chemical weathering is the main contributing factor for EC in the Dongjiang River Basin. The humanity interference cannot be neglected, while the seasalt settlement has certain effects on the hydrochemistry. Furthermore, the nonparametric statistics methods and spatial analysis are used to prove that the geographic features (lithology, landform, soil, vegetation and human activities) have played an important role in the EC mechanism.