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71.
The authors describe and discuss the new technique, multistep adaptive flux interpolation (MAFI), and its application to image data for coding. When applied to an image, MAFI produces an output which is also in an image form, but which has a more uniform feature density and a greatly reduced size. MAFI warps the input image by removing those rows and columns which contain a majority of redundant pixels. The side information required for reconstruction is minimal, and the image can be further compressed using conventional coders, making the compression ratio even higher. Because of its warped nature, the MAFI output's statistics are also more consistent with the properties assumed by block-based discrete cosine transform (DCT) methods  相似文献   
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Reported is an attempt to attain orientation of macromolecules during extrusion of films of cellulose derivatives that led to the liquid-crystalline state of a polymer and resulted in enhanced film strength.  相似文献   
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Scientific-Technical Center “Atomtekhénergo.” Leningrad Nuclear Power Plant. N. V. Sultanov Institute of Nuclear Reactors, Russian Scientific Center “Kurchatovskii institut.” Translated from Atomnaya énergiya, Vol. 76, No. 6, pp. 470–473, June, 1994.  相似文献   
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Simulation of very fast surge phenomena in a three-dimensional (3-D) structure requires a method based on Maxwell's equations, such as the finite-difference time-domain (FDTD) method or the method of moments, because circuit-equation-based methods cannot handle the phenomena. This paper uses a method of thin-wire representation of the vertical conductor system for the FDTD method which is suitable for the 3-D surge simulation. The thin-wire representation is indispensable to simulate electromagnetic surges on wires or steel frames in which the radius is smaller than a discretized space step used in the FDTD simulation. In this paper, a general surge analysis program named the virtual surge test lab based on the Maxwell's equations formulated by the FDTD method, is used to simulate the surge phenomena of a vertical conductor, including the effects of horizontal wave incidence and vertical wave incidence. Experimental results on the reduced scale model have been presented in order to compare among the simulation results by the FDTD method and the results using numerical electromagnetic code based on the MoM.  相似文献   
78.
A unified approach to decision making with extremal many-criteria models, expert estimates, and voting is developed on the basis of reference and distance concepts and taxonomy methods. It involves the solution of many-criteria problems with the Pareto optimum. Examples demonstrating the effectiveness and universality of the approach are given.  相似文献   
79.
We demonstrate, for the first time to our knowledge, that a fast coherent collision between two Kerr spatial solitons can give rise to a significant phase shift for both interacting beams. The maximal collision-induced phase shift ≈π rad takes place when the amplitudes of the solitons are equal (η12) and the length of the interaction zone is comparable with a soliton phase period. Depending on the ratio η21, and the collision angle between the solitons, the magnitude of the phase shift can be varied within a reasonable range, for example from 180° to 40°. The analysis of the effect performed by the finite-difference beam-propagation method has shown that it is insensitive to the initial phase difference between the incident beams (δi), even in the case when η 1≠η2. It has been demonstrated that the phenomenon can be used for all-optical three-soliton logic elements, which are capable of providing more than 3-dB signal amplification and possess bi -independent output characteristics  相似文献   
80.
A new sensitive method for imaging of the spatial distribution of microwave intensity is proposed. The method is based on the imaging of the 6P-recombination continuum of cesium, emitted from a nonequilibrium plasma of the positive column of gas discharge in a cesium vapor-xenon mixture. It is demonstrated that the spatial distribution of intensity of 35-GHz microwave radiation measured by this method in a focal plane of a lens well coincides with the pattern obtained with the aid of a movable microwave detector. The time resolution of the proposed microwave imaging system reaches 1 ms.  相似文献   
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