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991.
By using the hypothesis of the deformation of the straight bar and beamin mechanics of materials,a new engineering calculating model for a linear inclusion inplane is presented.Through the Kelvin's solution of a concentrated force,the inclusionproblem is reduced to solving a set of uncoupled singular integral equations which canbe solved by the numerical method of singular integral equation.Based on theseresults,several applicable examples including an inclusion-crack problem are calculatedand the results are quite satisfactory.  相似文献   
992.
Calculations have been carried out on spin-polarized Auger electron emission from a seven-layer chromium (lO0)-film. The core and valence states concerning the Auger transition are obtained from a self-consistent full-potential linearized augmented plane wave calculation by using a repeated slab geometry. The calculations refer to experiments on the L3M23 V- and L3 VV-transRions that have recently been carried out by Heinzmann et al. The Auger spectrum obtained for the L3VV transition agrees relatively well with our calculations, whereas the observed L3M23V-Auger structure is considerably wider than that predicted by our theory. Nevertheless, the spin-polarization in the latter case, which is about -13%, is in fair agreement with the experiment, different from the L3VV-transition where the experiment yields -10% as opposed to the theoretical value of -25%. We give possible reasons for the origin of these discrepancies.  相似文献   
993.
脉管制冷机直流机理研究和抑制方法探讨   总被引:1,自引:1,他引:0  
双向进气脉管制冷机中存在的直流流动不仅增加了冷端换热器的负载 ,降低了脉管制冷机的性能 ,而且还是引起脉管制冷机制冷温度不稳定的一个重要原因。文中从流体网络理论出发 ,分析了直流产生的机理 ,对目前各种抑制方法进行了探讨 ,指出了进一步研究的方向。  相似文献   
994.
In this work we present the behavior of a very compact XeCl laser system.Itconsists of an oscillator and an amplifier,both with lateral UV-preionization.Both dischargeelectrodes are contained in a single vessel.An unstable optical cavity is applied to the oscilla-tor.An output beam of 105 mJ,with a brightness of 5.5× 10~(l3)Wcm~(-2)Sr~(-1) and with a diver-gence of 0.9 mrad has been obtained.  相似文献   
995.
Micromechanics models have been developed for the determination ofthe elastic moduli of microcracked solids based on different approaches andinterpretations,including the dilute or non-interacting solution,the Mori-Tanakamethod,the self-consistent method,and the generalized self-consistent method.It isshown in the present study that all these micromechanics models can be unified withinan energy-equivalence framework,and that they differ only in the way in which themicrocrack opening and sliding displacements are evaluated.Relevance to thedifferential methods and the verification of these models are discussed.  相似文献   
996.
997.
EXISTENCEANDUNIQUENESSOFTHEENTROPYSOLUTIONTOANONLINEARHYPERBOLICEQUATION¥R.EYMARD;T.GALLOUET;R.HERBIN(LaboratoireCentraldesPo...  相似文献   
998.
Spatial Nonparametric Regression Estimation: Non-isotropic Case   总被引:3,自引:0,他引:3  
Data collected on the surface of the earth often has spatial interaction. In this paper, a non-isotropic mixing spatial data process is introduced, and under such a spatial structure a nonparametric kernel method is suggested to estimate a spatial conditional regression. Under mild regularities, sufficient conditions are derived to ensure the weak consistency as well as the convergence rates for the kernel estimator. Of interest are the following: (1) All the conditions imposed on the mixing coefficient and the bandwidth are simple; (2) Differently from the time series setting, the bandwidth is found to be dependent on the dimension of the site in space as well; (3) For weak consistency, the mixing coefficient is allowed to be unsummable and the tendency of sample size to infinity may be in different manners along different direction in space; (4) However, to have an optimal convergence rate, faster decreasing rates of mixing coefficient and the tendency of sample size to infinity along each direction a  相似文献   
999.
本文从实验的角度介绍从薄膜导波传播衰减研究光学薄膜损耗的方法,并以一些低损耗的光学薄膜样品的测量结果说明这种方法对损耗研究的灵敏程度及其优越性.  相似文献   
1000.
LARGE-TIMEBEHMIOROFSOLUTIONSFORTHESYSTEMOFCOMPRESSIBLEADIABATICFLOWTHROUGHPOROUSMEDIA¥XIAOLING(L.HSIAO)D.SERRE(InstituteofMat...  相似文献   
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