抽样机制对报文长度分布测度影响的研究     

张巍  丁伟  龚俭 《中国海洋大学学报(自然科学版)》2008,(Z1)

Claffy在1994年对1 h的主干数据分析的基础上,提出了基于时间驱动技术比基于报文驱动技术得出的抽样结果要差一些,但是二者之间的差别很小。为验证这个结论是否依然适用,以CERNET某2.5 G省网边界链路3个不同阶段连续1 h报文数据构成的Trace为对象,采用Claffy相似的方法,对报文长度分布测度进行了分析,获得了1组有关的结论,可以用于与网络测量和网络行为学有关的研究。  相似文献   

Experimental study on low temperature performance of polymer drilling mud agents     

ZHAN Jiajia  XU Huiwen  CAI Hongliang .College of Construction Engineering  Jilin University  Changchun  China .China Water Northeastern Investigation Design  Research Co.Ltd  Changchun  China 《东北亚地学研究》2009,12(1):32-35

Drilling fluid additives has a major impact on rheology behavior and other performances of the drilling fluid. The key to low temperature drilling fluids is choosing antifreeze and polymer agent which have a strong ability in resisting low temperature. On the basis of determining glycol as antifreeze agent, the low-temperatureperformance and capacities of anti-collapse of regular validity mud agents have been studied, the mechanism of anti-caving of the partially hydrolyzed polyacrylamide （PHPA）, polypropylene potassium （KPA） and PAC-141 polymer additives have been also analyzed. A pilot study of compatibility between ethylene glycol and the polymers has educed that the polymers, ethylene glycol and inorganic salt are compatible, and they can significantly reduce the freezing point of drilling fluid. Anti-collapse ability of the drilling mud is the results of synergistic action among the agents.  相似文献   

Numerical Analysis on the Effects of Submerged Depth of the Grid and Direction of Incident Wave on Gravity Cage   总被引：1，自引：0，他引：1  

陈昌平  李玉成  赵云鹏  董国海  桂福坤 《中国海洋工程》2009,23(2):233-250

In this paper,the numerical model of the net cage with the grid mooring system in waves is set up by the lumped mass method and rigid kinematics theory,and then the motion equations of floating system,net system,mooring system,and floaters are solved by the Runge-Kutta fifth-order method.For the verification of the numerical model,a series of physical model tests have been carried out.According to the comparisons between the simulated and experimental results,it can be found that the simulated and experimental results agree well in each condition.Then,the effects of submerged depth of grid and direction of incident wave propagation on hydrodynamic behaviors of the net cage are analyzed.According to the simulated results,it can be found that with the increase of submerged depth of grid,the forces acting on mooring lines and bridle lines increase,while the forces on grid lines decrease;the horizontal motion amplitudes of floating collar decrease obviously,while the vertical motion amplitudes of floating collar change little.When the direction of incident wave propagation changes,forces on mooting lines and motion of net cage also change accordingly.When the propagation direction of incident wave changes from 0° to 45°,forces on the main ropes and bridle ropes increase,while the forces on the grid ropes decrease.With the increasing propagation direction of incident wave,the horizontal amplitude of the forces collar decreases,while the vertical amplitude of the floating collar has little variation.  相似文献   

Underground water quality model inversion of genetic algorithm     

MA Ruijie  LI Xin. College of Mathematics  Jilin University  Changchun  China . College of Construction Engineering  China 《东北亚地学研究》2009,(3):164-167

The underground water quality model with non-linear inversion problem is ill-posed, and boils down to solving the minimum of nonlinear function. Genetic algorithms are adopted in a number of individuals of groups by iterative search to find the optimal solution of the problem, the encoding strings as its operational objective, and achieving the iterative calculations by the genetic operators. It is an effective method of inverse problems of groundwater, with incomparable advantages and practical significances.  相似文献   

Size-Dependent Growth Rate of Nitzschia closterium at Different Concentrations of Petroleum Hydrocarbon     

YANG Rujun  TANG Hongjie  XIN Yu    WANG XiulinCollege of Chemistry  Chemical Engineering  Ocean University of China  Qingdao  P. R. China 《中国海洋大学学报(英文版)》2009,8(1)

  相似文献   

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张静  赵超英  张勤  瞿伟 《大地测量与地球动力学》2009,29(5):143-146

?о?InSAR?α????????????????Kriging????????????????????????????1996??????SAR???????????????????е????????????????÷???????Ч?????α????????????????????????????????  相似文献   

The hydrogen peroxide impact on larval settlement and metamorphosis of abalone Haliotis diversicolor supertexta     

张祥景  杨志会  蔡中华 《中国海洋湖沼学报》2008,26(3)

Abalone Haliotis diversicolor supertexta is an important economic mollusk.The settlement and metamorphosis are two critical stages during its development period,which has direct influence on abalone survival and production.The influence of reactive oxygen species(hydrogen peroxide) on abalone embryo and juvenile development were examined in this study.Larvae of Haliotis diversicolor supertexta were induced to settlement and metamorphose by exposure to seawater supplemented with hydrogen peroxide.They had the best performance at 800 μmol/L.The concentration of 1 000 μmol/L or higher was toxic to the larvae,as the larvae could settle down only at benthic diatom plates without complete metamorphosis.In addition,H2O2 adding time was critical to the larval performance.24h after two-day post-fertilization was proved to be the optimal adding time.In this paper,two action mechanisms of hydrogen peroxide are discussed:(1) hydrogen peroxide has direct toxicity to ciliated cells,thus cause apoptosis;(2) hydrogen peroxide,as a product from catecholamines' autoxidation process in vivo,can reverse this process to produce neuro-transmitters to induce abalone metamorphosis.  相似文献   

Log evaluation of fractured igneous reservoirs in Songliao Basin   总被引：1，自引：0，他引：1  

Baozhi PAN Lihua ZHANG Ying ZHANG Chen HUANG 《东北亚地学研究》2007,10(1):65-68

The petrophysical parameters are bad in most igneous reservoirs of Songliao Basin because of the very low porosity and permeability. The evaluation of igneous reservoirs has not been fully studied so far. The current technique of formation evaluation and interpretation used in sedimentary formations face a series of prob- lems and difficulties. In this study, The PCA was used to identify lithology, a multi-mineral model “QAPM” was proposed. “Surface effect” must be considered when evaluating saturation. A software “SIMPLE” was developed and was used to deal with the logging data in over 70 wells with good results were achieved.  相似文献   

Application of integrated geophysical interpretation on accumulation body     

Caikun GAO Huakun DU Jingtian TANG Kangxiu WU Chang＇an XIAO Shiping WANG 《东北亚地学研究》2008,11(3):191-196

Integrated geophysical interpretation is a method of combinating different geophysics prospecting methods based on different physical properties of accumulation. As different geophysical methods own different interpretations and varying detection accuracies, the key issue becomes how to integrate the results of several geophysical methods to corrently carry out a comprehensive explanation. Based on different geophysical results, the authors proposed an integrated geophysical explanation method and successfully applied it in practical engineering problems.  相似文献   

Analysis of raft foundation design based on considering influence of superstructure stiffness     

WANG Bin  QIU Jianhui  ZHAO Dong  YANG Xi  DAI Shuai.College of Construction Engineering  Jilin University  Changchun  China .Design Institute of Jilin Architectural  Civil Engineering Institute  Changchun  China 《东北亚地学研究》2009,12(1):28-31

The finite element method was used for analysis of raft foundation design in high-rise building. Compared with other conventional methods, this method is more adapted to the practical condition since both superstructure stiffness and soil conditions were considered in calculation. The calculation results by example show that the base reaction is more uniform and the maximum reaction decreases obviously. Accordingly, the raft foundation design is more economic without any loss of security for high-rise building.  相似文献