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991.
992.
R. H. Enns D. E. Edmundson S. S. Rangnekar A. E. Kaplan 《Optical and Quantum Electronics》1992,24(11):S1295-S1314
In this paper we summarize what is currently known about optical switching between bright bistable soliton states in one and higher dimensions. A guideline to selecting media with appropriate intensity-dependent refractive indices to support bistable solitary waves is presented. The stability criterion for robustness of the solitary waves is discussed. Finally, some methods and numerical examples of optical switching are presented. 相似文献
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995.
Ho K. I. J. Leung J. Y. T. Wei W. D. 《Journal of Algorithms in Cognition, Informatics and Logic》1994,16(3)
We consider the problem of preemptively scheduling a set of imprecise computation tasks on m ≥ 1 identical processors, with each task Ti having two weights, wi and w′i. Two performance metrics are considered: (1) the maximum w′-weighted error; (2) the total w-weighted error subject to the constraint that the maximum w′-weighted error is minimized. For the problem of minimizing the maximum w′-weighted error, we give an algorithm which runs in O(n3 log2n) time for multiprocessors and O(n2) time for a single processor. For the problem of minimizing the total w-weighted error subject to the constraint that the maximum w′-weighted error is minimized, we give an algorithm which also has the same time complexity. 相似文献
996.
The authors study a one-dimensional model for optical tunnellingwith a refractive index in the shape of a square well. The relevanceof the model and its limiting cases are discussed. The mainresult is the leading behaviour of the exponentially small imaginarypart of the eigenvalue which determines the radiation loss.The leading behaviour of the imaginary part is calculated usingBerry's formula which controls the asymptotic expansion of theAiry function Bi(z) to better-than-exponential accuracy. 相似文献
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Ralf Jäger Anatolij I. Saprykin J. Sabine Becker Hans -Joachim Dietze José A. C. Broekaert 《Mikrochimica acta》1997,125(1-4):41-44
The analytical capabilities of a high-resolution mass spectrometer in combination with a 13.56 MHz glow discharge ion source for the analysis of semiconducting materials (silicon carbide and gallium arsenide) were studied. It was shown that single positively charged ions of sample material have about 10 eV higher average energy than the ions of the discharge and residual gas. Therefore effective energy separation of the ions of analyte from the ions of the discharge and residual gas was achieved by adjusting the ion transfer optics (breadth and position of energy slit), which improves the analytical capabilities of the developed method.Some analytical applications are presented to illustrate the performance of r.f. GDMS for the bulk analysis of semiconducting materials. The results of the trace element analysis of gallium arsenide and silicon carbide samples are compared with data of independent methods (LIMS, ICP-AES, SIMS).Dedicated to Professor Dr. rer. nat. Dr. h.c. Hubertus Nickel on the occasion of his 65th birthdayOn leave from the Institute of Inorganic Chemistry, 630090 Novosibirsk, Russia 相似文献