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Relationship between sampling intensity and precision for estimating damage to maize caused by rodents

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Integrative Zoology 2007年第3期2卷 131-135页

作者： Loth S.MULUNGU Rhodes h.MAKUNDI Apia W.MASSAWE herwig LEIRS Pest Management Centre Sokoine University of AgricultureMorogoroTanzania University of Antwerp Evolutionary Biology GroupAntwerpenBelgium Danish Pest Infestation Laboratory University of AarhusDepartment of Integrated Pest ManagementKongens LyngbyDenmark

In this study we aimed to determine the relationship between sampling intensity and precision for estimating rodentdamage. We used the systematic row sampling technique to provide data to achieve precision and accuracy inestimations of rodent damage in maize fields at the planting and seedling stages. The actual rodent damage to maizein 15 fields, each 0.5 ha in size, in Morogoro, Tanzania, was established at the seedling stage. These data were usedto simulate the sampling intensities that would provide precision and accuracy. The variations between estimateswere plotted against the sampling intervals. The results of this study show that the relationship between averagestandardized variances and sampling intervals is linear. The heterogeneous distribution of damage in some plotscaused variations in the accuracy of the estimates between plots, but a sampling interval of five rows consistentlyproduced estimates with a variance of less than 10%. We provide a standard curve that will allow a decision to bemade on the sampling intensity as a function of required precision using the systematic row sampling technique inmaize fields.

关键词： rodents sampling interval simulation standard curve systematic row sampling

Managerial Accounting 9th ed. 9th ed.; P.L.U.S. ed.; International ed.

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Study of abundant explicit wave solutions of the Drinfeld-Sokolov-Satsuma-hirota(DSSh)equation and the shallow water wave equation

2000年

作者： Ray h. Garrison

"Free CD included"--Cover.

ISBN: (纸本)0256260737

"Free CD included"--Cover.

关键词： Managerial accounting

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Propulsion and Power Research 2018年第4期7卷 320-328页

作者： h.M.Shahadat Ali M.Mamun Miah M.Ali Akbar Department of Applied Mathematics Noakhali Science and Technology UniversityNoakhali 3814Bangladesh Department of Mathematics Khulna University of Engineering&Technology.Khulna 9203Bangladesh Department of Applied Mathematics University of Rajshahi.Rajshahi 6205Bangladesh

In this article,the two variable(G'G,1/G)-expansion method is suggested to investigate new and further general multiple exact wave solutions to the Drinfeld-Sokolov-Satsuma-hirota(DSSh)equation and the shallow water wave equation which arise in mathematical physics with the aid of computer algebra software,like Mathematica.Three functions and the rational functions solution are found.The method demonstrates power,reliability and efficiency.Indeed,the method is the generalization of the well-known(G/G)-expansion method established by Wang et al.and the method also presents a wider applicability for conducting nonlinear wave equations.

关键词： Explicit wave solutions Computer algebra software Drinfeld-Sokolov-Satsuma-hirota(DSSh)equation Shallow water wave equation Soliton

Magnetic Field Gradient and Curvature-Driven Drift Modes in Toroidal Plasmas

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Chinese Physics Letters 2004年第8期21卷 1575-1577页

作者：王爱科 h.Sanuki 董家齐 F.Zonca K.Itoh SouthwesternInstituteofPhysics POBox432Chengdu610041 NationalInstituteforFusionScience TokiGifu509-5292Japan ENEAC.R.Frascati C.P.6500044FrascatiRomeItaly

A new kind of instability driven by the magnetic field gradient and curvature (MFGC) in toroidal plasmas is presented. It is found that the MFGC drift modes possess finite growth rates even if the plasma pressure gradient vanishes. In addition, the effects of plasma pressure gradient and safety factor on the MFGC modes have been analysed numerically.

关键词： Pressure gradient

Effect of Cerium Doping on Microstructure and Dielectric Properties of BaTiO_3 Ceramics

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Journal of Materials Science & Technology 2011年第8期27卷 759-763页

作者： Sabina Yasmin Shamima Choudhury M.A. hakim A.h. Bhuiyan M.J. Rahman Department of Physics University of Dhaka Materials Science Division Atomic Energy Centre Department of Physics Bangladesh University of Engineering and Technology

A solid state reaction method was used to synthesize barium titanate （BT） and barium cerium titanate （BCT） ceramics at sintering temperature of 1473 K for 4 h. The effect of cerium （Ce） on the structure, microstructure and dielectric properties of BCT was investigated. The scanning electron microscopy （SEM） investigations revealed that the grain size increases with increasing Ce content. The X-ray diffraction （XI^D） patterns showed mostly the BT phase, where the lattice parameter decreased with the addition of Ce. The temperature dependence of dielectric constant showed decrease in the phase transition temperature with higher Ce content. The dielectric constant decreased slightly with increasing frequency. The direct current （dc） density-voltage characteristics of the ceramics showed ohmic behavior for both the BT and BCT. As the temperature increased, the dc resistivity of the ceramics decreased. The activation energy increased with increasing Ce content.

关键词： Cerium doped Ba1-xCexTiO3 Dielectric constant Current density

Thickness Effect of Pulse Shaper on Dynamic Stress Equilibrium and Dynamic Deformation Behavior in the Polycarbonate Using ShPB Technique

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实验力学 2006年第1期21卷 51-60页

作者： O.S.Lee S.h.Kim Y.h.han School of Mechanical Engineering InHa University Incheon Korea Department of Mechanical Engineering InHa University Incheon Korea

The Split hopkinson Pressure Bar(ShPB) technique with a special experimental apparatus can be used to obtain the material behaviors under high strain rate loading condition. Attempts to apply the Split hopkison Pressure Bar in measurement on polymeric materials suffer from limitations on the maximum achievable strain and from high noise to signal ratios. This paper introduces a Split hopkinson Pressure Bar technique, to overcome these limitations. The proposed method uses aluminum pressure bars to achieve a closer impedance match between the pressure bars and the specimen materials, thus providing both data having a low noise to signal ratio and a longer input pulse at higher maximum strain. In addition, a pulse shaper technique was used for increasing the rise time of the incident pulse to ensure stress equilibrium and homogeneous deformation in the specimen under dynamic compression. A pulse shaper is utilized to lengthen the rising time of the incident pulse to ensure stress equilibrium and homogeneous deformation of polycarbonate. The dynamic deformation behaviors of Polymeric material under compressive high strain rate are evaluated using the modified ShPB technique.

关键词：厚度效应脉冲整形器动态应力平衡聚碳酸酯铝

Engineering circuit analysis = :工程电路分析 : sixth edition / 6th ed.

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Lung Development and Lung Injury-The New BPD

丛书名：国外电子与通信教材系列

2002年

作者： hayt William h.

本书是在“数字图像处理”第一版的基础上经过全面改写而成的，反映了过去10年中在数字图像处理领域的最新发展情况，是数字图像处理方面最为全面的专著。

ISBN: (纸本)7505376349

关键词： Electric circuit analysis.

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中国当代儿科杂志 2001年第4期 433-437页

作者： Alan h.Jobe Children’s hospital Medical Center!Cincinnati Oh45229-3039 USA

Bending,buckling and vibration analyses of MSGT microcomposite circular-annular sandwich plate under hydro-thermo-magneto-mechanical loadings using DQM

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International Journal of Smart and Nano Materials 2018年第4期9卷 233-260,I0002页

作者： M.Mohammadimehr M.Emdadi h.Afshari B.Rousta Navi Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashanIran

The purpose of this paper is to investigate the bending,buckling,vibration analyses of microcomposite circular-annular sandwich plate with CNT reinforced composite facesheets under hydro-thermo-magneto-mechanical loadings are presented using first order shear deformation theory(FSDT)and modified strain gradient theory(MSGT)that includes three material length scale parameters.Also,an isotropic homogeneous core is considered for microcomposite circular-annular sandwich plate.The generalized rule of mixture is employed to predict mechanical,moisture and thermal properties ofmicrocomposite sandwich plate.By using hamilton’s principle,governing equations are solved by differential quadrature method(DQM)for a circular annular sandwich plate.The predicted results are validated by carrying out the comparison studies for the FGM plates by modified couple stress theory(MCST).The obtained results are given to indicate the influence of the material length scale parameter,core-to-facesheet thickness ratios,magnetic effect,thermal andmoisture effects on the dimensionless deflection,critical buckling load,and natural frequency of microcomposite circular sandwich plate.The results can be employed in solid-state physics,materials science,nano-electronics,and nano electro-mechanical devices such as microactuators,and microsensor.

关键词： Bending buckling free vibration analyses circular annular sandwich plate CNT reinforced composite facesheets first order shear deformation and modified strain gradient theories