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Convergence speed and diversity of nondominated solutions are two important performance indicators for Multi-Objective Evolutionary Algorithms (MOEAs). In this paper, we propose a Resource Allocation (RA) model based on Game Theory to accelerate the convergence speed of MOEAs, and a novel Double-Sphere Crowding Distance (DSCD) measure to improve the diversity of nondominated solutions. The mechanism of RA model is that the individuals in each group cooperate with each other to get maximum benefits for their group, and then individuals in the same group compete for private interests. The DSCD measure uses hyper-spheres consisting of nearest neighbors to estimate the crowding degree. Experimental results on convergence speed and diversity of nondominated solutions for benchmark problems and a real-world problem show the efficiency of these two proposed techniques. 相似文献
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Copper(I) catalyzed radical benzylation and cyclization reaction of tertiary enamides was investigated and 3,3-disubstituted N-Alkyl isoindolin-1-ones were obtained in moderate to good yields. In this reaction, two new C–C bonds were formed in one step with high atom economy. Possible reaction pathway for the formation of the products was also discussed in this paper. 相似文献
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The aim of this work has been to study the influence of modified hole‐extraction layers on the performance of organic solar cells (OSCs) based on blends of poly (3‐hexylthiophene) and [6,6]‐phenyl‐C61‐butyric acid methyl ester. The hole‐extraction layers consist of poly (3,4‐ethylene dioxythiophene):polystyrene sulfonic acid (PEDOT:PSS) doped with different concentrations of bromine. Compared with pristine OSC without adding bromine to the hole‐extraction layer, the bromine‐doped OSCs show a 49% increase in the power conversion efficiency (from 2.12 to 3.16%), which could be attributed to the increase of electrical and optical properties of PEDOT:PSS films after the addition of bromine. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 50: 125–128, 2012 相似文献
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Mingli Jiao Kai Yang Wangxi Zhang Wei Pan Ruiwen Zhang Si Xie 《Journal of Macromolecular Science: Physics》2013,52(11):2103-2115
A series of poly(L-lactic acid)/polybutadiene (PLA/PB) biodegradable multiblock elastomers was synthesized and characterized. A two-step process to prepare PLA/PB multiblock elastomers was applied. Melt polymerization was used to prepare poly(L-lactic acid) (PLA) terminated with hydroxyl groups and, at the same time, hydroxyl-terminated polybutadiene (HTPB) and 1,6-hexamethylene diisocyanate (HDI) were employed to synthesize diisocyanate-terminated polybutadiene (ITPB). Then, PLA and ITPB were reacted with different PLA/PB weight ratios. Consequently, a series of PLA/PB biodegradable poly(ester-urethane)s with crosslinked chains was obtained. Swelling characteristics and crosslink density of the crosslinked elastomer were investigated. DMA was applied to characterize its thermal properties. The measurement of mechanical properties showed that a PLA/PB elastomer with adjustable mechanical properties was synthesized. Micromorphology, hydrophobicity, and degradability of the material were also characterized. 相似文献
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JIA YuPing GUO LiWei LU Wei GUO Yu LIN JingJing ZHU KaiXing CHEN LianLian HUANG QingSong HUANG Jiao LI ZhiLin CHEN XiaoLong 《中国科学:物理学 力学 天文学(英文版)》2014,(5):1004
<正>Addendum to:Science China:Physics,MechanicsAstronomy,2013,56(12):2386–2394doi:10.1007/s11433-013-5348-2The legends of the following Figures should be as follows:Figure 3 AFM morphologies and Raman spectra of a EG on a 2 inch SiC(0001)measured at five representative regions.(a)AFM Morphology reproduced from ref.[14]with permission from Science China Press and Springer publishing,(b)Raman spectra.Figure 6 SEM images of the VAGS.(a)Cross-section image of the VAGS;(b)and(c)are the top view images of the as-grown VAGS and the VAGS after top graphene layer removed reproduced from ref.[16]with permission from Wiley-VCH publishing. 相似文献
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