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51.
Daniel Smania 《Bulletin of the Brazilian Mathematical Society》2005,36(2):225-274
We study the dynamics of the renormalization operator for multimodal maps. In particular, we develop a combinatorial theory
for certain kind of multimodal maps. We also prove that renormalizations of infinitely renormalizable multimodal maps with
same bounded combinatorial type are exponentially close. Our results imply, for instance, the existence and uniqueness of
periodic points for the renormalization operator with arbitrary combinatorial type. 相似文献
52.
53.
Charles D. Immanuel Timothy J. Crowley Edward S. Meadows Cajetan F. Cordeiro Francis J. Doyle 《Journal of polymer science. Part A, Polymer chemistry》2003,41(14):2232-2249
This article presents a study on the engineering of multimodal distributions in semibatch emulsion polymerizations with nonionic surfactants. Various methods of producing multimodal distributions are demonstrated, and the sensitivity of the process to the properties of the reagents are analyzed. A test‐bed emulsion polymerization system, equipped with instrumentation to measure particle size distribution (capillary hydrodynamic fractionator) and monomer conversion (densitometer and flow meters), is used for this purpose. The process is monitored and controlled with an industrial distributed control system, which enables the automated operation of the process through sequential or logic controllers operating over lower level proportional integral derivative controllers. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2232–2249, 2003 相似文献
54.
Silica‐Encapsulated Gd3+‐Aggregated Gold Nanoclusters for In Vitro and In Vivo Multimodal Cancer Imaging 下载免费PDF全文
Xiaotong Wu Dr. Chunxia Li Suchan Liao Dr. Lu Li Dr. Tingting Wang Prof. Zhongmin Su Prof. Chungang Wang Jihong Zhao Changping Sui Prof. Jun Lin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(29):8876-8882
Gd3+‐aggregated gold nanoclusters (AuNCs) encapsulated by silica shell (Gd3+‐A‐AuNCs@SiO2 NPs) were strategically designed and prepared. The as‐prepared nanoparticles exhibit aggregation‐enhanced fluorescence (AEF), with an intensity that is up to 3.8 times that of discrete AuNCs. The clusters served as novel nanoprobes for in vitro and in vivo multimodal (fluorescence, magnetic resonance, and computed X‐ray tomography) cancer imaging 相似文献
55.
In the Jeffery-Hamel problem for a convergent channel, for small, moderately large and asymptotically large Reynolds numbers Re, multimodal, symmetrical and asymmetrical solutions not available in the literature are obtained and studied for the entire range of admissible convergence angles. For asymptotically small Re, these solutions depend singularly on Re. A number of novel hydrodynamic effects is established and commented on. 相似文献
56.
O. M. FALTINSEN 《力学进展》1971,47(1):201701
本文列举了诸多工程领域中的液体共振运动现象,详细探讨了船舱中伴有剧烈流动的晃荡问题.描述了基于理论分析的非线性多模态方法,该方法便于波动稳定性分区、多分支解和物理稳定性的研究.强调了方形舱、垂向圆柱舱以及球形舱内伴有旋转和混沌(不规则波动)的三维流动的重要性.晃荡引起的砰击涉及到各种各样的内流条件,这些条件随液体深度与舱体长度之比而变化.针对棱柱状LNG舱,讨论了许多与流体力学和热力学参数、影响砰击载荷效应的水弹性以及模型实验缩尺比的物理现象. 相似文献
57.
N. Baba 《Journal of Optimization Theory and Applications》1981,33(4):451-461
Matyas' random optimization method (Ref. 1) is applied to the constrained nonlinear minimization problem, and its convergence properties are studied. It is shown that the global minimum can be found with probability one, even if the performance function is multimodal (has several local minima) and even if its differentiability is not ensured.The author would like to thank Professors Y. Sawaragi (Kyoto University), T. Soeda (Tokushima University), and T. Shoman (Tokushima University) for their kind advice. 相似文献
58.
Antanas Žilinskas 《Operations Research Letters》1985,4(1):35-39
A new axiomatic characterization of a rational algorithm for global minimization based on a statistical model of the objective function is suggested. The globality of the search strategy of such an algorithm is investigated as well as the convergence of the algorithm. 相似文献
59.
为描述多方式城市交通网络下公交定价与出行选择行为的相互作用与影响,将出行方式选择与路径选择涵盖于同一网络,建立了上层模型分别以企业利润最大化、乘客出行成本最小化和社会福利最大化为目标函数,下层模型为多方式弹性需求随机用户配流模型的公交定价双层规划模型。运用改进遗传算法对模型整体进行求解,下层模型采用综合对角化算法和MSA算法的组合求解算法。最后,设计了一个算例以说明模型应用。结果表明:运用双层规划模型所确定的公交票价较传统静态票价可使政府、企业及出行者三方都获得更高收益,且上层模型以社会福利最大化为目标函数能代表社会群体中多数人利益,优化效果最为理想。 相似文献
60.
荧光成像技术因具有操作简便、分辨率高、安全性好且可实时成像等优势,在术中导航中具有广阔的应用前景。虽然目前还没有靶向荧光探针在临床上得到批准,但已经有相当一部分荧光探针进入了临床试验阶段。最早进入临床试验的是一些偶联肿瘤靶向配体的荧光染料,例如近红外菁染料(IRDye800CW)标记的肿瘤特异抗体,叶酸标记的异硫氰酸荧光素(EC17)等。近来,结构更复杂的荧光探针如酶反应激活型探针和PET/荧光双模态探针也逐步进入临床试验。本文依据近年来手术导航用荧光探针的最新研究进展,分别就受体介导的靶向荧光探针、可激活型靶向荧光探针、近红外二区(NIR-Ⅱ)荧光探针、多模态荧光探针和诊疗一体化探针进行了分类讨论,重点对正在进行临床研究及具有临床转化前景的荧光探针的分子设计原理进行了分析与总结,并对手术导航用荧光探针未来的发展进行了展望。 相似文献