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THEESTIMATIONOFPRIORFROMFISHERINFORMATION¥LIYUANZHANG;K.M.LALSAXENAANDQIANGWENJIUAbstract:InBayesiananalysis,themaximumentrop... 相似文献
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We have studied harmonic generation in the magnetic response of bulk samples of the ceramic superconductor TlBa2Ca3Cu4Oy. Dependence of the odd and even harmonics of magnetization on the DC magnetic field, amplitude of the AC magnetic field and temperature was investigate experimentally. We have used a critical state model recently developed by Müller et al. to calculate the full harmonic response. At fixed temperature, the dependence of the odd order harmonic response on the amplitude of the AC magnetic field Hm shows an unambiguous crossover from an H2m behaviour (Bean-like) at small amplitudes to an H3m behaviour for larger Hm, in quantitative agreement with the modified critical state model. 相似文献
76.
N. K. Jaggi 《Journal of statistical physics》1991,64(5-6):1093-1102
Results of computer simulations of a dense system of dipolar spheres in an electric field are summarized. Dissipative and Hamiltonian dynamics algorithms have been used to find energy minima of the system for varying particle densities. The structures obtained by these simulations are in reasonable agreement with experimentally observed structures in electrorheological (ER) fluids. Qualitative agreement is also obtained with the limited available experimental observations on the dynamics of ER fluids. 相似文献
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When a soft elastic cylinder is bent beyond a critical radius of curvature, a sharp fold in the form of a kink appears catastrophically at its compressed side while the tensile side remains smooth. The critical radius increases linearly with the diameter of the cylinder but remains independent of its material properties such as modulus; the maximum deflection at the location of the kink depends on both the material and geometric properties of the cylinder. The catastrophic dynamics of evolution of the kink depicts propagation of a shear wave from the location of the kink towards the edges signifying that kinking is an elastic response of the material which results in extreme localization of curvature. We have rationalized this phenomenon in the light of the classical Euler's buckling instability in slender elastic rods. 相似文献
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A parametric investigation of the friction performance of PC‐ABS parts processed by FDM additive manufacturing process 下载免费PDF全文
The friction performance is an important factor of parts processed by fused deposition modeling (FDM) for various engineering applications. It is one type of failure made of surface contact. The proper use of FDM process parameters can bring a significant reduction in friction and the amount of wear, thereby leading to a reduction in the material waste. To date, very little studies have been performed in this area. This paper investigates the effect of FDM manufacturing parameters on the friction performance of polycarbonate‐acrylonitrile butadiene styrene prototypes processed by FDM using definitive screening design and partial least squares method. The observation of surface morphology was obtained by the scanning electron microscopy to examine the effect of process parameters on the microstructure. The experimental results have shown that layer thickness, air gap, raster angle, and build orientation are the most influential factors affecting the friction performance of FDM manufactured parts. The proposed approach presented in this study provides an impetus to develop analytical modeling and functional relationships between FDM manufacturing parameters and friction performance. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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Kumar A Lal Tamta M Negi N Chandrasekhar K Singh Negi D 《Natural product research》2011,25(18):1680-1686
The essential oil of Premna latifolia Roxb. was obtained by hydrodistillation of fresh leaves of the plant having an oil yield of 0.05%, both non-polar and essential oil were analysed by GC and GC-MS. Hexane fraction of the leaves of P. latifolia was transesterified and analysed by GC and GC-MS, 40 non-polar components were identified comprising 89.3%. The most abundant fatty acid constituents were hexadecanoic acid (25.04%), 8,11,14-docosatrienoic acid (13.62%), octadecanoic acid (6.82%), 9,12-octadecadienoic acid (4.19%) and 29 components were investigated in the essential oil which comprises 78.1%. The most abundant oil constituents were 1-octen-3-ol (35.69%), terpendiol II (7.19%), δ-guaiene (7.49%) 2-undecanone (4.80%) and α-pinene (3.27%). Different extracts were also tested against polyphagous crop pest Spodoptera litura for antifeedant activity. Essential oil showed maximum growth reduction of 56.83% followed by chloroform extract of 43.93%. 相似文献
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In this paper, a singularly perturbed delay differential equation of first order has been considered. The problem is solved by using a hybrid scheme on a Shishkin mesh. The difference scheme is shown to converge to the continuous solution uniformly with respect to the perturbation parameter. Truncation errors are obtained. Finally, numerical experiments are carried out on a test problem, confirming the effectiveness of the proposed technique. 相似文献