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451.
We study regularity of mild and strong solutions of an abstract mathematical model of a flexible space structure under appropriate initial conditions. We apply our results showing qualitative properties of the trajectories in the case of the negative Laplacian operator. 相似文献
452.
Ravi P. Agarwal Claudio Cuevas Herme Soto 《Nonlinear Analysis: Theory, Methods & Applications》2011,74(5):1769-1798
This work deals with the existence and uniqueness of pseudo-almost periodic and asymptotically ω-periodic mild solutions to some evolution equations in Banach spaces. 相似文献
453.
Mild steel was coated by hot-dipping into a molten aluminum bath. The microstructure and phase evolution in the aluminide layer during diffusion at 750 °C in static air were analyzed by electron backscatter diffraction (EBSD). The results showed that the aluminide layer of the as-coated specimen consisted of an outer aluminum topcoat, minor FeAl3 and major Fe2Al5, respectively. Also, Fe2Al5 possessed a tongue-like morphology, which caused corresponding serration-like morphology in the steel substrate. A portion of the peaks of serration-like substrate were isolated, after short exposure at 750 °C, and accompanied by the formation of voids, which continued to appear with further exposure at 750 °C. As the aluminum topcoat was consumed, FeAl3 phase disappeared and left an aluminide layer of Fe2Al5 phase. After 60 min of exposure, FeAl2 and FeAl phases formed at the interface between Fe2Al5 and the steel substrate. With increasing exposure time, the voids condensed and the serration-like morphology disappeared, while FeAl2 and FeAl phases kept growing. After prolonged exposure, the aluminide layer was composed of FeAl2 and FeAl and possessed a flat interface between FeAl and steel substrate. 相似文献
454.
Jeffrey B. Vancouver Charles A. Scherbaum 《Computational & Mathematical Organization Theory》2008,14(1):1-22
Self-regulation theories in applied psychology disagree about whether action or perceptions are the focus of regulation. Computational
models based on the two conceptualizations were constructed and simulated. In one scenario, they performed identically and
in conjunction with participants in a study of the goal-level effect (Vancouver et al., Organ Res Methods 8:100–127, 2005). In another scenario they created differentiating predictions and only the computational model based on the self-regulation
of perceptions matched the data of participants. Implications for research and practice are discussed.
相似文献
Jeffrey B. VancouverEmail: |
455.
Supplier selection problem, considered as a multi-criteria decision-making (MCDM) problem, is one of the most important issues for firms. Lots of literatures about it have been emitted since 1960s. However, research on supplier selection under operational risks is limited. What’s more, the criteria used by most of them are independent, which usually does not correspond with the real world. Although the analytic network process (ANP) has been proposed to deal with the problems above, several problems make the method impractical. This study first integrates the fuzzy cognitive map (FCM) and fuzzy soft set model for solving the supplier selection problem. This method not only considers the dependent and feedback effect among criteria, but also considers the uncertainties on decision making process. Finally, a case study of supplier selection considering risk factors is given to demonstrate the proposed method’s effectiveness. 相似文献
456.
Dwijendra N. Pandey Amit Ujlayan 《Nonlinear Analysis: Theory, Methods & Applications》2009,71(9):3690-3698
In this paper we study a class of fractional order integrodifferential equations considered in an arbitrary Banach space. Using the theory of analytic semigroups we establish the existence, uniqueness and regularity of a mild solution to these fractional order integrodifferential equations. 相似文献
457.
In this paper the existence and uniqueness of different types of solutions to a class of semilinear retarded differential equations with nonlocal history conditions are obtained by a fixed point argument. Also finite dimensional approximation of these solutions in a Hilbert space is established. 相似文献
458.
Ravi P. Agarwal Selma Baghli Mouffak Benchohra 《Applied Mathematics and Optimization》2009,60(2):253-274
The controllability of mild solutions defined on the semi-infinite positive real interval for two classes of first order semilinear
functional and neutral functional differential evolution equations with infinite delay is studied in this paper. Our results
are obtained using a recent nonlinear alternative due to Avramescu for sum of compact and contraction operators in Fréchet
spaces, combined with the semigroup theory. 相似文献
459.
Yang Zhou Monica K. Chawla Jose L. Rios-Monterrosa Lingzhi Wang Marc A. Zempare Victor J. Hruby Carol A. Barnes Minying Cai 《Molecules (Basel, Switzerland)》2021,26(20)
Brain G-protein coupled receptors have been hypothesized to be potential targets for maintaining or restoring cognitive function in normal aged individuals or in patients with neurodegenerative disease. A number of recent reports suggest that activation of melanocortin receptors (MCRs) in the brain can significantly improve cognitive functions of normal rodents and of different rodent models of the Alzheimer’s disease. However, the potential impact of normative aging on the expression of MCRs and their potential roles for modulating cognitive function remains to be elucidated. In the present study, we first investigated the expression of these receptors in six different brain regions of young (6 months) and aged (23 months) rats following assessment of their cognitive status. Correlation analysis was further performed to reveal potential contributions of MCR subtypes to spatial learning and memory. Our results revealed statistically significant correlations between the expression of several MCR subtypes in the frontal cortex/hypothalamus and the hippocampus regions and the rats’ performance in spatial learning and memory only in the aged rats. These findings support the hypothesis that aging has a direct impact on the expression and function of MCRs, establishing MCRs as potential drug targets to alleviate aging-induced decline of cognitive function. 相似文献
460.
Phuong?Tuyen?Nguyen Ursula?Rammelt Waldfried?PliethEmail author 《Journal of Solid State Electrochemistry》2003,7(8):497-502
The protection mechanism of intrinsically conducting polymers (ICPs) is still under discussion. Most of the discussions concentrate on the effect of the redox behavior and electroactivity of ICPs on the corrosion protection. In the present paper it is shown that polymethylthiophene (PMT) films electropolymerized on mild steel, with 2-(3-thienyl)ethylphosphonic acid used as adhesion promoter, show the desired redox activity. The interaction between the PMT film and some conventional coatings, and the influence of the pH of electrolyte, were investigated. It was shown that the electroactivity of PMT film is lost by the interaction with coatings of high nucleophilicity and is markedly decreased by immersion in an aqueous solution of pH 11. 相似文献