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991.
An approach to solving a linear interpolation problem in a fuzzy information space is proposed. Two different schemes of interpolation
are outlined: a heuristic one, based on the geometrical interpretation of operations, and an optimization one, based on the
expansion principle. The results obtained allow performing fuzzy linear prediction.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 55–68, March–April 2006. 相似文献
992.
It is established that bismuth crystals under the simultaneous action of a constant magnetic field and current pulses exhibit a correlation between the microhardness and the mobility of twinning dislocations. It is shown that application of the external fields favors translation of the twinning dislocations along the twin-matrix boundaries. 相似文献
993.
994.
995.
N S Sergeeva M Iu Vasil'ev T I Kovalenko N V Sokolova G I Avdeev 《Eksperimental?nai?a onkologii?a》1989,11(2):35-37
The indirect immunofluorescent technique was used to study the distribution of the ascitic fluid antigen (AgD) on histological sections from surgical specimens of gastric and colon tumours from proximal to distal lines of resection. AgD was found in gastric tumours exceptionally in the tumour area and in colon cancer--both in the tumour stroma and in surrounding histologically normal mucosa. 相似文献
996.
V. V. Skorokhod N. K. Prokushev I. O. Shmatko 《Powder Metallurgy and Metal Ceramics》1987,26(11):875-880
Conclusions A method is proposed making it possible to study the high-temperature kinetics of the variation of the coefficients of shear ductility of a porous solid and its material during sintering under pressure. An investigation was carried out into the variation of the ductility of copper powder compacts in the temperature range 700–950°C. Experimental data are compared with results obtained on the basis of the theory of diffusion-viscous flow and a general rheological theory of sintering. It has been established that in the initial stage of sintering at 950°C the coefficient of shear ductility of copper increases linearly with time. Under conditions of diffusion-viscous flow of a polycrystalline material, this is due to diffusional grain growth according to a parabolic law. It is shown that experimental values of shear ductility of copper are smaller than values obtained on the basis of the rheological theory of sintering. Values approximating most closely to experimental data have been obtained with a model of an ideal porous solid.Translated from Poroshkovaya Metallurgiya, No. 11(299), pp. 11–17, November, 1987. 相似文献
997.
Multiple-access interference (MAI) and multipath fading are two of the most significant factors limiting the capacity and performance of direct-sequence code-division multiple-access (DS-CDMA) systems. In this paper, synchronous multiuser receivers that combine antenna diversity, RAKE reception, and a multipath decorrelator for MAI cancellation are analyzed in a Nakagami faded environment using a maximal ratio combiner or a selection combiner. A coherent binary phase-shift keying employing DS-CDMA is considered. Arbitrary branch correlation is also considered for any diversity order in the case of identical severity fading on the branches. 相似文献
998.
The physical properties of aluminum thin films depend strongly on their microstructure, which can be characterized using different techniques. In the present work, aluminum thin films—grown with different thickness on silicon substrates—were analyzed by atomic force microscopy (AFM) and grazing incidence x-ray techniques. The AFM was used as a high-resolution profilemeter for measuring edge angles, step heights, surface microstructure, and roughness. The structural properties (such as crystallographic orientation, crystallite size, and phase identification) were analyzed by grazing incidence x-ray diffraction. For small thickness, AFM images show small nucleation sites because of the short time of growth. Grain size grows as the thickness increases, and film morphology seems to be uniform with large grains. The AFM results of as-grown films show a linear increase in roughness along with thickness. Roughness values decrease with aging time after film preparation, until a constant value is observed. All films mainly have (111) orientation, and its intensity grows with film thickness, with respect to the (200) and (220) peaks. As the film thickness increases, the surface stress decreases. 相似文献
999.
The optimum procedures for synthesis of UO2CO3 and Na4[UO2(CO3)3] were developed. The structures of these compounds and their thermal decomposition were studied by X-ray diffraction, precision IR spectroscopy, and thermography. The standard enthalpy of formation of crystalline Na4[UO2(CO3)3] at 298.16 K was determined to be -4010.0±8.0 kJ mol-
1. 相似文献
1000.
Koudymov A. Xuhong Hu Simin K. Simin G. Ali M. Yang J. Asif Khan M. 《Electron Device Letters, IEEE》2002,23(8):449-451
We demonstrate a novel RF switch based on a multifinger AlGaN/GaN MOSHFET. Record high saturation current and breakdown voltage, extremely low gate leakage current and low gate capacitance of the III-N MOSHFETs make them excellent active elements for RF switching. Using a single element test circuit with 1-mm wide multifinger MOSHFET we achieved 0.27 dB insertion loss and more than 40 dB isolation. These parameters can be further improved by impedance matching and by using submicron gate devices. The maximum switching power extrapolated from the results for 1A/mm 100 /spl mu/m wide device exceeds 40 W for a 1-mm wide 2-A/mm MOSHFET. 相似文献