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1.
Genetic algorithms are stochastic search algorithms that have been applied to optimization problems. In this paper we analyze the run-time complexity of a genetic algorithm when we are interested in one of a set of distinguished solutions. One such case occurs when multiple optima exist. We define the worst case scenario and derive a probabilistic worst case bound on the number of iterations required to find one of these multiple solutions of interest. 相似文献
2.
Preparation and Spectroscopical Investigations of Trivinyl- and Triallylfluorosilane Trivinyl- and Triallylfluorosilane were prepared. The i.r. and Raman spectra have been recorded. The discussion of intra- and intermolecular interactions is based on the spectroscopic data. 相似文献
3.
4.
Spectroscopie Investigations on R? C6H4O(CH3)2SiF Compounds The i.r. and Raman spectra of a number of R? C6H4O(CH3)2SiF compounds (R = H, CH3, CH3O, Cl, Br, NO2, NH2) have been recorded. The intramolecular and intermolecular interactions were discussed by means of ν SiF, ν Si? O? (C), ν C? O? (Si) and νs SiC2 vibrations. 相似文献
5.
6.
The effect of surfactants on surface instabilities of thin liquid film flow on a rotating disk was studied at different flow rates Q (0.5相似文献
7.
K. F. Koehler H. Zaddach A. D. Kuntsevich V. N. Voznesenskii I. I. Chervin R. G. Kostyanovsky 《Russian Chemical Bulletin》1993,42(10):1757-1759
The1H and13C NMR spectral parameters of α-, β-, and y-lewisites1–5 were obtained and a new isomer,cis,trans,trans-γ-lewisite5, was isolated and identified on the basis of chemical shifts, relative intensities of the signals, and the intra-chain (3
J
hh
,3
J
ch
) and interchain (3
J
casch
) coupling constants.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1833–1835, October, 1993. 相似文献
8.
The following substances could be prepared by Grignard reactions or by conversions with trichlorosilane: C6F5CH2CHCH2, C6F5(CH2)3SiCl3, CF3(CF2)9CH2CHCH2, CF3(CF2)7(CH2)2SiCl3, CF3(CF2)11(CH2)3CHCH2 und CF3(CF2)11(CH2)5SiCl3.They were characterized by spectroscopical and microanalytical methods. 相似文献
9.
Secondary structure motifs in nucleic acid probes generally impair intended hybridization reactions and so efforts to predict and avoid such structures are commonly employed in probe design schemes. Another key facet of probe design that has received much less attention, however, is that secondary structure at targeted probe binding site regions may also impair hybridization. Thus, evaluation of both probe and target site secondary structures together should improve hybridization prediction and design effectiveness. Several challenges confound this goal, including imperfect empirical rules and parameters underlying predictions and the fact that folding algorithms scale poorly with respect to sequence length. Here, we attempt to quantify the consequences of target site structure on predicted hybridization using sequences sampled from the human genome. We also provide a methodology for choosing a reasonable “window size” around target sites that is as small as possible without compromising folding algorithm prediction accuracy. 相似文献