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991.
A general formalism for the study of nonlinear pulse propagation in optical fibres is presented. It is then applied to study the time evolution of a Gaussian laser pulse in a fibre with cubic and fifth-order nonlinearity in the index of refraction. The results are presented and discussed. 相似文献
992.
A. M. Pristrem N. I. Danilovich V. A. Labunov 《Journal of Engineering Physics and Thermophysics》1987,53(6):1464-1472
By using integral transform methods, an approach is developed to the solution of a problem on the temprature distribution in multilayer structures heated by cw scanning laser radiation, with phase transitions in the layers taken into account.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 53, No. 6, pp. 1000–1010, December, 1987. 相似文献
993.
994.
995.
R. Breil T. Fries J. Garnaes J. Haycocks D. Hüser J. Joergensen W. Kautek L. Koenders N. Kofod K. R. Koops R. Korntner B. Lindner W. Mirand A. Neubauer J. Peltonen G. B. Picotto M. Pisani H. Rothe M. Sahre M. Stedman G. Wilkening 《Precision Engineering》2002,26(3)
Comparison measurements on reference standards are reported in which 13 partners with different instruments took part. A set of prototype standards which had been produced and calibrated within a European project were used for the measurements. Here, results of measurements on a 240 nm step height standard and a two-dimensional lateral standard with a nominal pitch of 1 μm are reported. 相似文献
996.
Cavagnino A. Lazzari M. Profumo F. Tenconi A. 《Industry Applications, IEEE Transactions on》2002,38(6):1517-1524
The aim of this paper is the comparison of the axial flux (AF) structures versus the conventional radial flux (RF) structures for permanent-magnet synchronous motors. The comparison procedure is based on simple thermal considerations. Two motor typologies are chosen and compared in terms of delivered electromagnetic torque. The comparison is developed for different motor dimensions and the pole number influence is put into evidence. The paper reports the complete comparison procedure and the related results analysis. The obtained results show that, when the axial length is very short and the pole number is high, the AF motors can be an attractive alternative to the conventional RF solutions. 相似文献
997.
M. N. Magomedov 《Technical Physics Letters》2002,28(5):430-433
Expressions for the calculation of the parameters of self-diffusion in a crystal of simple substance at temperatures close
to absolute zero are derived. It is established that, in “loose” crystal structures (with the first coordination number below
12), the amount of atoms involved in diffusion motion exceeds the number of vacant sites in the crystal lattice at T=0 K. The results of calculations of the vacancy and diffusion parameters at T=0 K for ten cryocrystals show that the phenomenon of “nonvacancy self-diffusion at T=0 K” can take place only in bcc helium. 相似文献
998.
Computer graphics in art history and archaeology 总被引:2,自引:0,他引:2
999.
A cartographic approach to visualizing conference abstracts 总被引:4,自引:0,他引:4
A cartographic approach to mapping nongeographic information helps to manage graphic complexity in visualizations. It aids domain comprehension by forcing us to use the same cognitive skills we use when viewing geographic maps. The author presents a distinctly cartographic approach to mapping nongeographic information. Focusing on the text content of a set of conference abstracts, we can derive 2D visualizations of information spaces that address complexity and automation 相似文献
1000.
A. N. Utkina Yu. Yu. Cherkis M. N. Kozlova V. L. Kozlov 《Metal Science and Heat Treatment》1982,24(4):270-273
Conclusion To ensure the required characteristics of the diffusion layer in heat-resistant steels, it is recommended to subject them to two-stage nitriding: saturation at 950°C for 2 h in endogas with an addition of 12% natural gas and 4% ammonia, lowering the temperature to 900°C, holding for 5 h in endogas with an addition of 6% natural gas and 4% ammonia; exchange of gas 6 times.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 4, pp. 34–36, April, 1982. 相似文献