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71.
72.
Summary In this paper we give a method to solve Saint-Venant's problem for inhomogeneous and anisotropic elastic cylinders when the elastic coefficients are independent of the axial coordinate. The cross-section of the cylinder is assumed to be occupied by different inhomogeneous and anisotropic elastic materials. Dedicated to Prof.Dario Graffi on his 70th birthday Entrata in Redazione il 15 maggio 1975.  相似文献   
73.
This paper presents the numerical investigation of the microtube heat sink with impingement jet feeding. The inlet channel covers only the quarter of the tube perimeter so the swirl flow is settled in the tubes and the heat transfer between the liquid flow and silicon substrate is improved. The water with the variable physical properties is used as the working fluid and laminar flow regime is considered. The proposed microtube heat sink with impingement jet feeding is compared with classic microtube heat sink in terms of temperature variation along the heated surface and temperature difference. The influence of the temperature dependent physical properties on the fluid flow and heat transfer is analyzed.  相似文献   
74.
We show that the spectral-tile implication in the Fuglede conjecture in dimension 1 is equivalent to a Universal Tiling Conjecture and also to similar forms of the same implication for some simpler sets, such as unions of intervals with rational or integer endpoints.  相似文献   
75.
Functional data clustering: a survey   总被引:1,自引:0,他引:1  
Clustering techniques for functional data are reviewed. Four groups of clustering algorithms for functional data are proposed. The first group consists of methods working directly on the evaluation points of the curves. The second groups is defined by filtering methods which first approximate the curves into a finite basis of functions and second perform clustering using the basis expansion coefficients. The third groups is composed of methods which perform simultaneously dimensionality reduction of the curves and clustering, leading to functional representation of data depending on clusters. The last group consists of distance-based methods using clustering algorithms based on specific distances for functional data. A software review as well as an illustration of the application of these algorithms on real data are presented.  相似文献   
76.
This paper discusses two arylenevinylene oligomers with optical nonlinear properties. Their trans molecular structure was confirmed by Fourier Transform Infrared Spectroscopy and Nuclear Magnetic Resonance. Second Harmonic Generation and two-photon fluorescence have been observed on Matrix Assisted Pulsed Laser Evaporation-deposited thin films. We have seen two local maxima in UV-Vis spectra and a red shift of the photoluminescence peak for carbazole-based oligomer, which can be correlated with a higher conformational flexibility and with strong polarization interactions in the solid state. Scanning Electron Microscopy and Atomic Force Microscopy images have revealed a grainy morphology of the film deposited on titanium and a higher roughness for carbazole-based oligomer. Second harmonic measurements have shown nearly equal values of the second-order nonlinear optical coefficient for the triphenylamine and carbazole-based oligomers for Plaser < 100 mW. z-Scan and x-scan representations of the carbazole-based oligomer film have shown strong two-photon fluorescence intensity inside the sample confirming a volume process, and a strong second harmonic at the surface of the sample determined by the surface morphology.  相似文献   
77.
In this paper, we study a class of quasi-invariant measures on paths generated by discrete dynamical systems. Our main result characterizes the subfamily of these measures which admit a certain disintegration. This is a disintegration with respect to a random walk Markov process which is indexed by the starting point of the paths. Our applications include wavelet constructions on Julia sets of rational maps on the Riemann sphere.

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78.
79.
Summary The Student distribution is obtained by means of the principle of maximum entropy.  相似文献   
80.
It is shown that a selenium diode biased in the reverse direction is characterized by several features special to MIS structures. The effect of ionic processes in the MIS structure on the volt-amp characteristics is studied.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 7–11, November, 1973.  相似文献   
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