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991.
Choon Ki Ahn 《Nonlinear dynamics》2012,67(1):573-586
In this paper, a new exponential state estimation method is proposed for switched Hopfield neural networks based on passivity
theory. Through available output measurements, the main purpose is to estimate the neuron states such that the estimation
error system is exponentially stable and passive from the control input to the output error. Based on augmented Lyapunov–Krasovskii
functional, Jensen’s inequality, and linear matrix inequality (LMI), a new delay-dependent state estimator for switched Hopfield
neural networks can be achieved by solving LMIs, which can be easily facilitated by using some standard numerical packages.
The unknown gain matrix is determined by solving delay-dependent LMIs. Finally, a numerical example is provided to demonstrate
the effectiveness of the proposed method. 相似文献
992.
Background
Pitch identification had yielded unique response patterns compared to other auditory skills. Selecting one out of numerous pitches distinguished this task from detecting a pitch ascent. Encoding of numerous stimuli had activated the intraparietal sulcus in the visual domain. Therefore, we hypothesized that numerosity encoding during pitch identification activates the intraparietal sulcus as well. 相似文献993.
In this study, we present a new and very accurate numerical method to approximate the Fisher’s-type equations. Firstly, the
spatial derivative in the proposed equation is approximated by a sixth-order compact finite difference (CFD6) scheme. Secondly,
we solve the obtained system of differential equations using a third-order total variation diminishing Runge–Kutta (TVD-RK3)
scheme. Numerical examples are given to illustrate the efficiency of the proposed method. 相似文献
994.
Péter R. Surján Ágnes Szabados Péter Jeszenszki Tamás Zoboki 《Journal of mathematical chemistry》2012,50(3):534-551
Properties and some applications of strongly orthogonal geminals (APSG) are reviewed emphasizing the motivations for their
use and their shortcomings. An overview presents some techniques capable of improving the APSG function. 相似文献
995.
Hui Zhao Shinji Mitsuiki Mikako Takasugi Masashi Sakai Masatoshi Goto Hiroaki Kanouchi Tatsuzo Oka 《Applied biochemistry and biotechnology》2012,166(7):1758-1768
Insoluble and hard-to-degrade animal proteins are group of troublesome proteins, such as collagen, elastin, keratin, and prion
proteins that are largely generated by the meat industry and ultimately converted to industrial wastes. We analyzed the ability
of the abnormal prion protein-degrading enzyme E77 to degrade insoluble and hard-to-degrade animal proteins including keratin,
collagen, and elastin. The results indicate that E77 has a much higher keratinolytic activity than proteinase K and subtilisin.
Maximal E77 keratinolytic activity was observed at pH 12.0 and 65 °C. E77 was also adsorbed by keratin in a pH-independent
manner. E77 showed lower collagenolytic and elastinolytic specificities than proteinase K and subtilisin. Moreover, E77 treatment
did not damage collagens in ovine small intestines but did almost completely remove the muscles. We consider that E77 has
the potential ability for application in the processing of animal feedstuffs and sausages. 相似文献
996.
This paper deals with the problem of active vibration suppression using the concept of delayed resonator (DR) absorber with acceleration feedback. A complete dynamic analysis of DR and its coupling with a single degree of freedom mechanical system are performed. Due to the presence of a delay in the acceleration feedback, the dynamics of the resonator itself, as well as the dynamics of combined system are of ‘neutral’ character. On this system, spectral methods are applied to perform a complete stability analysis. Particularly, the method of cluster treatment of characteristic roots is used to determine stability boundaries in the space of the resonator parameters. Based on this analysis, a methodology to select the resonator parameters is proposed in order to guarantee desirable suppression characteristics and to provide safe stability margins. An example case study is included to demonstrate these analytical results. 相似文献
997.
Yu Chen Youyi Zhao Ming Wang Hao Sun Yunfa Dong Xu Feng 《Chemistry of Natural Compounds》2012,47(6):940-943
An original triterpenoid saponin, named lonimacranthoide I, was isolated from the flower buds of Lonicera macranthoides (Caprifoliaceae). It has hederagenin as aglycone. Lonimacranthoide I is a rare chlorogenic acid ester acylated at C-23 of
hederagenin. The structure of the saponin was established based on chemical and spectral methods. 相似文献
998.
Laura C. Oliveira Cibele B. Zamboni Edson A. Pessoa Fernanda T. Borges 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(2):395-398
In this investigation ions in serum, urine and kidney of Wistar rats (control group) and Wistar with Acute Renal Insufficiency
(ARI) were quantified using instrumental neutron activation analysis. The measurements in serum and urine were performed before,
during and after ischemia-induced ARI. The measurements in kidney were performed for the control and ARI groups. Also, a comparative
analysis between the concentration ratios before, during and after ARI was performed in urine and serum samples for both groups.
The variations results for Cu in serum and I in urine, before and after ischemia-induced ARI, suggest that these elements
must be also investigated in renal dysfunction. 相似文献
999.
1000.
A solvent extraction process is proposed to recover uranium and thorium from the crystal waste solutions of zirconium oxychloride.
The extraction of iron from hydrochloride medium with P350, the extraction of uranium from hydrochloride with N235, and the
extraction of thorium from the mixture solutions of nitric acid and the hydrochloric acid with P350 was investigated. The
optimum extraction conditions were evaluated with synthetic solutions by studying the parameters of extractant concentration
and acidity. The optimum separation conditions for Fe (III) are recognized as 30% P350 and 4.5 to 6.0 M HCl. The optimum extraction
conditions for U (VI) are recognized as 25% N235 and 4.5 to 6.0 M HCl. And the optimum extraction conditions for Th (VI) are
recognized as 30% P350 and 2.5 to 3.5 M HNO3 in the mixture solutions. The recovery of uranium and thorium from the crystal waste solutions of zirconium oxychloride was
investigated also. The results indicate that the recoveries of uranium and thorium are 92 and 86%, respectively. 相似文献