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991.
Tie-Jun Liu Yue-Sheng Wang Chuanzeng Zhang 《Archive of Applied Mechanics (Ingenieur Archiv)》2008,78(4):267-282
The main interest of this study is a new method to solve the axisymmetric frictionless contact problem of functionally graded
materials (FGMs). Based on the fact that an arbitrary curve can be approached by a series of continuous but piecewise linear
curves, the FGM is divided into a series of sub-layers with shear modulus varying linearly in each sub-layer and continuous
at the sub-interfaces. With this model, the axisymmetric frictionless contact problem of a functionally graded coated half-space
is investigated. By using the transfer matrix method and Hankel integral transform technique, the problem is reduced to a
Cauchy singular integral equation. The contact pressure, contact region and indentation are calculated for various indenters
by solving the equations numerically.
An erratum to this article can be found at 相似文献
992.
993.
Multiple MIPS 4Kc cores based interrupt controller design and its implementation on HDTV SoC platform 总被引:2,自引:0,他引:2
A multiple MIPS 4Kc processor cores based interrupt processing system is introduced. The interrupt controller plays a key role in the high definition television (HDTV) system-on-a-chip (SoC) platform, especially when it is a multiple processor system. Based on a general introduction to the whole HDTV SoC platform, a layered interrupt controller and its implementation are discussed in detail. The proposed scheme was implemented in our FPGA verification board. The results indicate that our scheme is reliable and efficient. Meanwhile, as a functional intellectual property (IP), the interrupt controller has reusability and expandability with the layered structure. 相似文献
994.
995.
We demonstrate three-dimensional tomographic imaging using a Fresnel lens with broadband terahertzpulses.Objects at various locations along the beam propagation path are uniquely imaged on the sameimaging plane using a Fresnel lens with different frequencies of the imaging beam.This procedure allowsthe reconstruction of an object's tomographic contrast image by assembling the frequency-dependentimages. 相似文献
996.
997.
The polycrystalline sample of layered compound FePS_3 has been investigated by using M?ssbauer spectroscopy (12K to 300K), magnetic susceptibility measurements, x-ray diffraction and FTIR spectroscopy. The antiferromagnetic order exists below T_N=120.5±1K. The M?ssbauer spectra below T_N indicate that the magnetization axis is perpendicular to the layer of FePS_3, and the divalent iron cations are in their high spin configurations. By fitting the hyperfine field parameters near the Néel temperature, we obtain information on the nature of magnetic interactions in the material. The results show that the magnetic coupling can be treated by the two-dimensional Ising model, and it can be interpreted on the basis of a crystal-field effect. 相似文献
998.
以美国南弗洛里达州递避飓风袭击为例建立了紧急输送情况下的线性规划模型。其中具体建立了以SCEPD(美国南弗洛里达州紧急情况预防部门)提出的公路反向,地区分块撤离,使用小路等三个最受人们关注的策略的模型。模型的灵敏度分析能很好地解释建立更多的临时避难所、限制车辆等策略对撤离的影响。在相近的环境下,中模型解得的结果很接近官方预测的结果,并且本的模型能对更广泛的情况进行分析.可给SCEPD提供一定参考。 相似文献
999.
A method for direct sulfenylation of aldehydes and ketones, catalyzed by a novel pyrrolidine trifluoromethanesulfonamide organocatalyst, has been developed. This process serves as an efficient and mild approach to the preparation of α-phenylthio-ketones and -aldehydes. 相似文献
1000.
ChujiangCai ZhigangShen MingzhuWang ShulinMa YushanXing 《中国颗粒学报》2003,1(4):156-161
This paper reports the use of a colloidal Pd^0 catalysis system to metallize the surface of precipitators separated from coal fly-ash, and metals such as Cu, Ni etc. are deposited on the precipitators surface. Alternatively, according to the characteristic surface of cenospheres, an Ag coating catalysis system is adopted to first deposit Ag on the cenospheres surface, followed, if necessary, by the deposition of other metals such as Cu, Ni, etc. on the Ag coating to produce monolayer and multilayer metal-coated cenospheres. The surface characteristics and the morphologies of the metal coatings are examined in detail with scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) techniques. It can be shown that the quality of metal coatings derived from the Aa coatina catalysis system, is better than that of the colloidal Pd^0 catalysis system. 相似文献