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    An Efficient and Deterministic Algorithm to Determine Irreducible and Primitive Polynomials over Finite Fields
    WANG Xin;WANG Xinmei;WEI Baodian
       2009, 48 (1): 6-9.  
    Abstract3702)      PDF (965KB)(234)      
    An efficient and deterministic method is proposed to determine whether a polynomial over finite fields is irreducible (primitive) or not. The correlation between the degree of the polynomial and its irreducible factors is analyzed, and then a sufficient and necessary condition on judging whether a polynomial of arbitrary degree n over finite fields is irreducible (primitive) or not is presented. By applying the Euclidean Algorithm, this judgment can be verified with O((log2 n)n3) multiplicative operations over finite fields. The proposed algorithm is accomplished in polynomial time and easy to be implemented on hardware. And it is an efficient method for construction of the Linear Feedback Shift Register for spread communication and the stream cipher to find and use irreducible polynomials.
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    Comparative Analysis of Parameter Estimation Methodsof Generalized Extreme Value Distribution
    CHEN Zishen;LIU Zengmei;LU Jianfei
       2010, 49 (6): 105-109.  
    Abstract2834)      PDF (4826KB)(241)      
    Three parameter estimation methods of generalized extreme value distribution function were briefly introduced in the paper, which included the maximumlikelihood estimation, the linear moment estimation and the maximum product of spacing estimation. Two demonstration examples including monthly maximum runoff at Makou Station and daily maximum precipitation in Guangzhou over the past years were analyzed by the three parameter estimation methods of GEV distribution. The results indicated that three parameters obtained by three different estimation methods were very close. Several goodness fit tests showed that two examples were obeyed the generalized extreme value distribution. And the designed values predicted by maximum product of spacing estimation were better fitted with the measured values.
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    Analysis of Physical Characteristics, Composition of Tephrosia vogelii Hook f.Seeds and its Oil Component
    YU Xin;YAN Zhuoqin;LI Xiaohua;HUANG Xuelian;ZENG Xiaofang
       2009, 48 (1): 37-41.  
    Abstract2725)      PDF (1302KB)(165)      
    The physical characteristics and chemical macro components of Tephrosia vogelii Hook f. seeds were analyzed. The constitutes of fatty acid and glyceride in oil were determined by gas chromatography-mass spectroscopy(GC-MS)and the technology of liquid chromatographymass equipped with selective detector of electrospray ionization anionic trap (LC-MSD-Trap-XCT). The nutritional evaluation about oil was evaluated. The result showed that the size of seeds was 4.63 mm×4.01 mm×1.92 mm, 1 000grain weight 1.52 g, soil bulk density was 659.8 g/L, the angle of automatic flow was 25.89°, the angle of repose was 23.15°, mass fraction of water and volatile matter was 9.89%, crude fat was 13.47%, crude protein was 38.73%, carbohydrate was 33.21% (soluble sugar 10.54%, starch 10.76%, crude fiber 11.91%), ash 4.84% Acid value, peroxide value, saponification value, iodine value, density and refraction coefficient of oil of Tephrosia vogelii Hook f.seeds were 2.7 mg/g, 1.17 mmol/kg, 188 mg/g, 1.18 g/g, 0.859 9 g/mL, 1.464 8, respectively Fatty acid ingredients were as following(w/%): Tetradecanoic acid was 0.15%,pentadecanoic acid 0.031%, hexdecanoic acid (palmitic acid) 18.68%,hexadecenoic acid 0.023%,heptanoic acid 0.12%,stearic acid 6.46%,oleic acid 19.26%,linoleic acid 38.76%,linolenic acid 8.38%,eicosanoic acid 1.90%,eicosenoic acid 0.52%,heneicosanoic acid 0.12%,docosanoic acid 4.09%,tricosanoic acid 0.16%, tetracosanoic acid 1.35%, furthermore, amount of unsaturated fatty acid was 66.94% Monoglyceride esters of fatty acid content were 0.11% diglyceride of fatty acid 0.180%, triglyceride of fatty acid 99.687% in dried oil. Tephrosia vogelii Hook f. seeds whose indexes were all accorded with Chinese and other countries’edible soybean oil standard (GB/T15352003, Codex-Stan 210) contained high amount of fat and protein and were rich with human essential linoleic acid and linolenic acid.
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    Research on Matrix Standardized Method for Resource Scheduling
    ZHOU Jiantao;LU Haiyan;YE Xinming
       2009, 48 (1): 128-132.  
    Abstract2626)      PDF (1273KB)(116)      
    Resource scheduling is one of the most important problems in the area of ComputerSupported Cooperative Work. Standardization of decision matrix is a basic problem for resource scheduling. Firstly, three matrix standardized methods were introduced. Then they were applied to the same example of decision matrix for resource scheduling. Finally, the best result matrix was proposed after comparing processing time and the results of these methods.
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    Vector Construction and Prokaryotic Expressing of OsRad21-i,a Novel Gene Coding Sister Chromatid Protein ofHybrid Indica Rice (Oryza Sativa.ssp.indica)
    KANG Haiqi;SHEN Guoan;YANG Jinshui;CHENG Zaiquan
       2009, 48 (1): 62-66.  
    Abstract2432)      PDF (2189KB)(162)      
    OsRad21-i (GeneBank accession number AY318757) was cloned from the root of Shanyou 63, the famous hybrid rice variety (Oryza sativa ssp. indica). It belongs to cohesinlike family, which mediates rice sister chromatid cohesion during mitosis and meiosis. The complete ORF of OsRad21-i, containing the restriction sites of BamHI and SalI introduced by primers, was named Eqfr and cloned into pGEM-T vector. The recombinant clone, DH5α[pGEMTEqfr], was screened and identified using PCR. The plasmids of pGEMTEqfr and pQE30 were respectively digested with BamHI and SalI at the same time. After the segregation of electrophoresis, the linear pQE30 vector and digested Eqfr were ligated by T4 DNA ligase at 4 ℃ overnight. The competent cell of M15[pREP-4] was transformed by the diluted ligation product. The recombinant clones of M15[pQE30-Eqfr, pREP-4] were identified. All of the plasmids in these recombinant clones were respectively extracted and digested with both endonucleases BamHI and SalI. The restriction pattern was in agreement with the predicted pattern. It showed that the target clone containing pQE30-Eqfr was obtained. In addition, the target clones were cultivated and induced to express the desired protein by IPTG. The molecular mass of expressed protein was about 116 000. The expression quantity was high in the first to third hour after induction, but declined after the third hour. This revealed that the ORF of OsRad21-i theoretically deducted at before was right. The expressed protein and system would be beneficial to next step experiment.
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    Delay-dependent Robust HControl for Uncertain Fuzzy Systems with Delay
    ZHANG Guo;LI Junmin
       2009, 48 (1): 10-15.  
    Abstract2427)      PDF (1276KB)(125)      
    A delaydependent robust H control problem for a class of uncertain TS fuzzy systems with delay is presented. Based on a fuzzy LyapunovKrasovskii functional (LKF) and fuzzy freeweighting matrices with timedelay, a new delaydependent robust stability criterion is proposed and proved for the close-loop fuzzy system. The feedback controller design involves solving a set of linear matrix inequalities (LMIs) via parallel distributed compensation (PDC) approach. Finally, simulation results are presented to show the effectiveness of the approach.
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    A Highly Efficient Protocol for Transformation of Saccharomyces cerevisiae and Pichia pastoris by Electroporation
    XU Zhiwu ;ZHANG Ying;WANG Zhixue;CAO Yan;CUI Liang;LI Sheng;LIU Qiuyun
       2010, 49 (3): 98-101.  
    Abstract2394)      PDF (904KB)(229)      
    Electroporation is widely used for highly efficient transformation of Saccharomyces cerevisiae. As many strains degenerate over time or over environmental exposure, their electroporation efficiencies could drop markedly by 2 to 3 orders of magnitude. Here we describe a modified electroporation procedure which included single stranded carrier DNA for electroporation as well as a postelectroporation growth period in YPD medium, which gave rise to 13 fold enhancement in transformations than an optimized lithium acetate (LiAc) and dithiothreitol (DTT) Pretreatment protocol previously reported. An enhancement of 114 fold on Pichia pastoris transformations has been observed using the modified procedure. The modified method enhanced the transformation efficiencies of some degenerated S. cerevisiae strains by nearly 100 fold. It will enable molecular manipulations in all kinds of S. cerevisiaeand P. pastoris strains by allowing propagations of all sorts of DNA libraries made from minute samples.
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    DOU Lei;MA Jin;ZHOU Yongzhang;LI Yong;AN Yanfei;ZHANG Chengbo
       2008, 47 (1): 98-102.  
    Abstract2382)      PDF (1244KB)(145)      
    Sixty-one soil samples and corresponding leafy vegetable samples were collected from Dongguan which is a Township-Enterprise-Prosperity-Area of Guangdong Province, the total content and extractable concentration of 5 heavy metal elements (Cu, Zn, Cr, Ni and Pb) were measured. Results show that the leafy vegetables have obvious problems of both the excess of toxic metal (Pb, Ni) and the shortage of useful metal (Zn, Cu). The metal concentrations in leafy vegetable had no significant correlations with either the total or the extractable heavy metal concentrations in soil. While the heavy metal concentration in leafy vegetable evidently related to the accumulation factors calculated from extractable heavy metal concentration. It might indicate that using the extractable heavy metal to evaluate the effect of heavy metal to the crop in soil was not enough to reflect the adverse effects to ecological system. The same type of vegetables have different absorbability to different heavy metals, different vegetables have different absorbability to the same heavy metal. Generally,the leaf vegetables have strong selective absorbability to heavy metals. Cr was the easiest element to be selectively absorbed,Zn, Cu, Ni was the second, Pb was the weakest absorbed. But the extractable content and the ratios of extractable content to total content of Cr, Zn, Cu in soils are low,the content of Cr, Zn, Cu in vegetables are not exceeded the limits of standard of food sanitation. The source of excessive lead in vegetable is complicated and mostly originates from air polluted with lead.
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    Video Content Authentication Technique Based on Cloud Watermark
    LIANG Changyin ;LI Ang;NIU Xiamu 
       2009, 48 (1): 26-30.  
    Abstract2353)      PDF (1648KB)(152)      
    Digital video content authentication technique becomes a hot point. A novel video content authentication scheme, based on cloud watermark and shot segmentation, is proposed. The related technique on the Invariant Feature extraction, the generation of the cloud watermark, the embedding and the extraction of cloud watermark, the authentication and the tamper detection on video were studied and implemented . With some experiments and the corresponding analysis and the verifying for the results, the scheme can be applied into the real time video and may not affected the visual efficient.
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    Cited: Baidu(5)
    The Analysis and Forecast of Eco-environmental Quality ofWetland in Panyu of Guangzhou
    ZHENG Yanwei;QIAN Lexiang;ZHENG Zhuo;WANG Xiaojing;HUANG Kangyou;CAO Linglong;YANG Shixiong
       2008, 47 (5): 104-109.  
    Abstract2344)      PDF (1639KB)(121)      
    Evaluation of ecoenvironment quality based on remote sensing(RS), geographical information system(GIS) and neural network were carried out on Panyu district of Guangzhou. The results show that the background of ecological environment has changed radically: from 1979 to 2006, the proportion of building area were increased from 2.43% to 29.94% in 2004 and it reached 37.82% in 2006; the proportion of paddy field area were increased from 42.92% to 49.19% in 1990, but it decreased to 22.70% in 2000 and it reached 17.97% in 2006; so the background in Panyu changed from paddy field area in 1979 to building area in 2006. The qualities of the local wetland ecological environment were declining from 1979 to 2000. The ecological environment qualities were good and the ecological effects is less than 2.2 in 1997. During 1990 to 2000, there are some changes in the ecological environment qualities. The ecological environment qualities of some of the wetland were good and the ecological effect was 2.2-3, but the ecological effect in bad environment was over 3.8. After changing from wetland background to building background in 2006, the relative quality of this area got better and the ecological effect was less than 2.2. According to the prediction values of the ecological effect classification of wetland from 2011 to 2016, the qualities of coastal wetland in Panyu will be attributed to the normal level, the ecological effects will be 3.2.
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    Smart Antenna and its DSP Simulation for PHS WirelessCommunication Systems
    XIE Ning;ZHOU Yuanping;LI Weike;WANG Weiquan
       2008, 47 (2): 50-53.  
    Abstract2320)      PDF (1447KB)(115)      
    PHS system is used in many big cities for such as small size and low power,but the cover ranges of PHS system are too small to be popularized further. Because smart antenna technique can obviously overcome this shortcoming,a smart antennas receiver for PHS wireless Communication system and a complete set of DSP hardware simulation platform are set up. Then an analysis and comparison of the performance of the receiver, including the performance of the realtime adaptive algorithm of smart antennas receiver based on simulation platform are presented. Also, the results of the experiment are given.
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    Trends in All Kinds of Precipitation Events in China over the Past 40 Years
    MIN Shen;QIAN Yongfu
       2008, 47 (3): 105-111.  
    Abstract2302)      PDF (1761KB)(151)      
    Based on daily rainfall dataset of 542 stations in China during the period of 1960-2003, the trends in all kinds of precipitation events in China are briefly studied in this paper. The results show that.the increasing total precipitation amount is mainly caused by the rising extreme precipitation (EP), and the reducing sprinkle frequency is the major reasons of the decreasing rain days. A decrease in rain days is observed in most regions of China, and EP events still have increased trends in many areas at the same time, so the lessening rain days could not reduce the possibility of EP. The trend of the sprinkle frequency is the most obvious change in all kinds of precipitation events, and declining is the main trend throughout most parts of China. A significant increase in EP events is observed in western China in all seasons. The EP events have decreased in the Yangtze River and southern China in autumn, but increased in the other three seasons. In northern and northeastern China, EP events show an increase in winter and a half increase in the other seasons. The ratio of EP amount to total precipitation amount is generally increasing in most areas of China,suggesting that the precipitation event has an obvious trend of extremeness.
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    Cited: Baidu(51)
    Response Surface Method for Reliability Computation Based on Support Vector Regression
    LIU Ji-ke;ZHAO Wei
       2008, 47 (1): 1-4.  
    Abstract2285)      PDF (878KB)(133)      
    On the complicated or implicit limit state functions in the reliability problems, a response surface method for reliability computation based on Support Vector Regression (SVR) is presented. A fit of the limit state function is constructed by this method. The partial derivatives of the fit could be easily computed and further be used to calculate the reliability through the ordinary first or second order reliability method. Firstly, the required training samples by Latin Hypercube sampling are generated in this paper. Secondly, the substituted function of the limit state function is obtained using the SVR. Thirdly, the reliability index and failure probability are calculated by the ordinary gradient optimization method. Results of the numerical examples justify the reliability and effectiveness of the proposed method, which provides a new approach for the reliability computation.
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    Cited: Baidu(11)
    Synthesize of ZnO Nanobelt Arrays by SolidThermal Oxidation with Au Catalyst
    REN Shan;YE Zhichao;HU Zhuofeng;BAI Yunfan;DU Wenzhe;QIN Xizhou
       2008, 47 (3): 47-50.  
    Abstract2280)      PDF (2129KB)(124)      
    ZnO nanobelt arrays were successfully synthesized on zinc substrate by low temperature (400 ℃) solid thermal oxidation of Zn with Au catalyst. XRD,SEM and HRTEM were used to examine and identify the morphology and the crystal structure of the nanobelts. The Au promotes the growing of the ZnO nanobelts obviously. The ZnO nanobelts have a thickness of 40 nm with widths of 100 to 150 nm and lengths of 6 to 14 μm. Not any gold particle were found on the tips of the nanobelts in HRTEM observations. XRD patterns show the crystal structure of the ZnO nanobelts is hexagonal, and the phase structure of ZnO nanobelts is similar to the ZnO nanowires synthesized by Au catalystfree method. The PL measurements also took on the sample; two peaks can be seen in the PL spectra.
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    Characterization of Chlorination Products of Nonylphenol by GC/MS and LC/MS in Aqueous Solution
    SI Jing;ZHOU Haiyun;HE Jianguo
       2008, 47 (3): 67-70.  
    Abstract2271)      PDF (975KB)(106)      

    NaClO was added to the aqueous solution containing nonylphenol. The CHCl3 extract of the chlorination product was analyzed by using GC/MS and LC/MS. Two kinds of products including monochlorononylphenol and dichlorononylphenol were found by both methods.The isomers of nonylphenol and its chlorination products could be detected by GC/MS method.By comparing the relative intensity of the isotope from mass spectrum of the products and the search information from the NIST Library, mono(m/z 254) and dichlorononylphenols (m/z 288) were deduced beside the nonylphenol (m/z 220). In terms of the data from LC/MS, similar results were found. When applying (-) ESI mode, [M-H]molecular weight for each kind of chlorination compound was obtained.(-)ESIMS direct injection mode could be used as a rapid screening method for analysis of these kinds of compound.

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    Zinc Accumulation in Different Tissues of Spodoptera litura Fabricius Larvae
    XIA Qiang;SHU Yinghua;HU Xinjun;SUN Hongxia;ZHANG Guren
       2008, 47 (3): 89-93.  
    Abstract2270)      PDF (1449KB)(114)      
    Zinc accumulation in different tissues of 1stand 3rd phytophagous insect Spodoptera litura Fabricius larvae were investigated by adding various doses of zinc into artificial diets of S. litura larvae. Inductively Coupled PlasmaAtomic Emission Spectrometer (ICPAES) was used to measure the concentration of zinc in different tissues of S. litura larvae. Results showed that zinc was accumulated in the midgut,fat body and cuticle of 6th instar larvae in the 1stand 3rd generations of S. litura.Accumulations of Zinc in different tissures increased with the increasing zinc doses in diets and the doseresponse with zinc doses in diets was singificant. The concentration of zinc in midgut was the highest among the three kinds of tissues.
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    Calculation of Limit Cycles and Their Stability and Bifurcationsfor Planar Quadratic Differential Systems
    HUANG Chengbiao;WU Huadong
       2008, 47 (2): 28-31.  
    Abstract2248)      PDF (786KB)(117)      
    It is very helpful to determine the number, the function expression, their shapes and positions in the phase plane and the bifurcation curves in the parameter plane of the plane quadratic differentiation system in the fields of ecological,biological and applied sciences, e.g. nonlinear oscillations.The x coordinates of limit cycle phase portraits for planar quadratic polynomial differential systems are supposed as the generalized harmonic function. The approximate analytical expressions of y coordinates, frequency, periodic, stability index and bifurcation about the parameter are calculated by alternate method. The present will provide a way to solve the known as the Hilberts problem 16 (second part as n=2). Am example with three limit cycles surrounding the singular point (0, 0) is shown.
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    The Intelligent Fitting Method for Valve Core Curve Based on FlowCharacteristics of Regulating Valve
    LI Zhanming;WANG Yunfeng;YUAN Zhanting
       2009, 48 (1): 22-25.  
    Abstract2243)      PDF (1045KB)(159)      
    The study was conducted on large flotation equipment in ore plants of Jinchuan Group Ltd during 2006, the intelligent fitting method of valve core curve is proposed based on the linear flow characteristic of regulating valve. Optimal curve fitting is determined based on replenishment quantity of flotation process and model of BP neural network with using the different shape of valve core curve. Industrial experiments have shown that the method has a wide using prospect with high reliability, high stability of the flotation machine liquid level and high effectiveness of level control system.
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    Secure and Efficient Implementation for RSA Cryptographic Algorithm
    ZHANG Baohua;YIN Xinchun
       2008, 47 (6): 22-26.  
    Abstract2240)      PDF (1113KB)(155)      
    The implementation of RSA cryptosystems is vulnerable to SCA attacks such as power analysis and time attack. First countermeasures for the exponentiation computation of RSA cryptographic algorithm were summarized. Then the software countermeasures based on random probability and hardware countermeasure based on the 3-adic representation of exponent were proposed. Analysis shows that the two countermeasures achieved great improvements in both security and efficiency compared to existed countermeasures. Both two generic countermeasures can be transplanted to the scalar multiplication of ECC.
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    Cited: Baidu(6)
    Application of Artificial Immune Network in Flood Classification
    ZHANG Ling;CHEN Xiaohong;WENG Yi;LIU Qinger
       2008, 47 (5): 110-114.  
    Abstract2240)      PDF (1132KB)(109)      
    After summarizing flood classification research,a novel flood classifier employing artificial Immune network was proposed to carry out immune memory and learning of the flood sample. The useful characteristics that effectively represent the flood intensity are extracted to produce antibody repertoires and similarity matrix. Then minimum spanning tree is used to classify flood sample by calculating the affinity between antigen and memory cell sets. The proposed classifier was testified by 12 typical hydrographs of Yichang station and 17 typical hydrographs of Shigou station. The results show that the proposed classifier classified the similar flood into same class by extracting the fuzzy characteristics and removing redundant information. Comparing with Evolutionary Particle Swam Optimization, the classifier fastens the convergence rate.
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    Cited: Baidu(11)