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991.
This paper aimed at exploring the use of the proposed hybrid Fuzzy-Particle Swarm Optimization-Simplex (F-PSO-S) algorithm to optimize the structural design of PM couplings subject to several key design constraints. The new proposed hybrid optimization algorithm is constructed based on combining three well-known techniques: fuzzy logic (FL), particle swarm optimization (PSO), and simplex method (SM). FL is used to aggregate different scaling and/or conflicting objectives in one objective function using fuzzy combination operators. On the other hand, the PSO has obvious capabilities in global search whereas the SM has exceptional advantages in local search. As a hybrid algorithm, the F-PSO-S has the outstanding feature of combining the ability of global searching and local canvassing for different scales and/or conflicting objective functions. The proposed algorithm has been applied to permanent magnet (PM) drive couplings. A standard coupling design is used as a good initial point for the conventional SM and to define the performance constraints for the proposed optimization technique. New coupling designs are developed and optimized to show the superior capabilities of the F-PSO-S algorithm as a global optimization technique. The sensitivity analysis is also performed to identify the effects of different design parameters on the coupling performance. 相似文献
992.
Chaowen Shen Simin Yu Jinhu Lü Guanrong Chen 《International Journal of Circuit Theory and Applications》2015,43(12):2039-2056
Over the last two decades, chaotification has received increasing attention from various communities of science and engineering. This paper aims at developing a unified chaotification framework for generating desired higher‐dimensional dissipative hyperchaotic systems by using a single‐parameter controller. The main idea is to use a block diagonal matrix in the design of the nominal system, so as to construct a desired hyperchaotic system. Specifically, the proposed scheme is to assign desired closed‐loop poles to the controlled system, allocating the corresponding numbers of eigenvalues with positive real parts at two types of saddle‐focus equilibria. For the non‐degenerate case, the number of positive Lyapunov exponents of the controlled system is given by the largest number of positive Lyapunov exponents of the desired hyperchaotic system. Two representative examples are given to illustrate and verify the proposed design method. Finally, the digital signal processor is employed to implement the above 10‐dimensional hyperchaotic systems, and the experimental observation is also given. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
993.
Kevin M. P. van Eeten Dennis H. J. Hülsman John van der Schaaf Jaap C. Schouten 《American Institute of Chemical Engineers》2015,61(11):3656-3665
A novel type of rotor‐stator spinning disk device is proposed which allows for the entrapment of solid particles solely by hydrodynamic means. In this new configuration, the solid rotating disk is replaced with two conjoined rotors with a variable gap spacing. Liquid is fed through the top stator and can flow out again through the rotor‐rotor interior and the hollow rotation axis. Moreover, the volume between the two rotors is optionally filled with a highly porous reticulated carbon foam. It was found that particle containment was strongly improved by the presence of this reticulated foam as it hinders the buildup of centripetal boundary layer flow near the disks in the interior of the rotor‐rotor assembly. These centripetal boundary layers drag along particles resulting in a loss of containment. Experiments utilizing glass beads showed that particles with a diameter down to 17.8 µm can be completely entrapped when a carbon foam is placed between the two conjoined disks at rotor speeds up to the maximum investigated value of 178 rad s?1. Additionally, the rotor‐rotor gap did not have an effect on the particle entrapment level when the reticulated carbon foam was omitted and can be ascribed to the build‐up of boundary layers, which is independent of rotor‐rotor distance. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3656–3665, 2015 相似文献
994.
Swelling kinetics,mechanical properties,and release characteristics of chitosan‐based semi‐IPN hydrogels 下载免费PDF全文
Two series of pH‐sensitive semi‐interpenetrating network hydrogels (semi‐IPN) based on chitosan (CS) natural polymer and acrylamide (AAm) and/or N‐hydroxymethyl acrylamide (HMA) monomers by varying the monomer and CS ratios were synthesized by free radical chain polymerization. 5‐Fluorouracil (5‐FU), a model anticancer drug, has been added to the feed composition before the polymerization. The characterization of gels indicated that the drug is molecularly dispersed in the polymer matrix. The swelling kinetics of drug‐loaded gels have decreased with increased HMA content at 37°C in both distilled water and buffer solutions with a pH of 2.1 or 7.4. Elastic modulus of the gels increased with the increase in HMA content and higher CS concentration enhanced the elastic modulus positively. Moreover, cumulative release percentages of the gels for 5‐FU were ca. 10% higher in pH 2.1 than those in pH 7.4 media. It was determined that they can be suitable for the use in both gastric and colon environments. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41886. 相似文献
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996.
The aims of this study were to prepare organogels from pomegranate seed oil (PO) with carnauba wax (CW) and monoglyceride (MG), compare the organogels with a commercial margarine (CM) and evaluate 3 months storage stability. At 3% organogelator addition, no gels were formed, while at 7 and 10% additions, the oil binding capacities increased and were always higher in CW organogels, with crystal formation times of 8.0 to 14.0 min. Solid fat content (SFC) of the CW organogels varied between 2.96 and 8.71% at 20°C, while MG gels had 2.89–9.43%, and CM had 29.73% SFC. The peak melting temperatures of the CW organogels ranged from 74.73 to 75.74°C and MG organogels ranged from 11.09 to 50.63°C, whereas CM product exhibited 45.92°C peak melting temperature. The hardness of CW organogels was higher than that of MG organogels. The organogels showed potential as spreadable products. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41343. 相似文献
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