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Multimedia Tools and Applications - In this work, a new fuzzy logic-based algorithm is proposed for the enhancement of low light color images. A generalization of a fuzzy set known as an... 相似文献
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Experiments were performed to investigate the mechanism underlying the potentiation of N-methyl-D-aspartate (NMDA) responses by carbachol (CCh) in the CA1 region of rat hippocampal slices. CCh (300 nM) potentiated responses to NMDA, but not to alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), in a readily reversible manner. Potentiation occurred in slices treated with 200 nM tetrodotoxin and perfused with Mg(2+)-free medium. It also occurred in slices treated with either staurosporine (1 microM), which is a potent inhibitor of a variety of protein kinases including protein kinase C (PKC), or thapsigargin (10 microM), which depletes intracellular Ca2+ stores by preventing their refilling. However, CCh-induced potentiation was abolished in slices perfused with Ca(2+)-free medium. These data suggest that low concentrations of CCh can acutely potentiate NMDA responses in the hippocampus by a Ca(2+)-sensitive process that is probably independent of both the activation of PKC and the release of Ca2+ from intracellular stores. This mechanism is similar to that underlying the potentiation of NMDA responses by the metabotropic glutamate receptor (mGluR) agonist, aminocyclopentane-1S,3R-dicarboxylic acid (1S,3R-ACPD). 相似文献
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Based on the experience of the gasifier users on the efforts and energy for wood chip preparation in a typical gasifier, we have embarked on the development of a gasifier suitable to work with long stick woody biomass as the feed materials. In the context of the impact of gasifiers, as decentralized energy delivery devices such an approach, it is hoped, would be an attractive option in rural areas both in domestic and industrial sectors. In the present paper in the gasifier operation, there is a fixed quantity of char that is combusted to gasify a fixed amount of wood, and the gasifier does not operate in a steady state manner. In this present work, focus is made on the development of a gasifier using long sticks of wood as feed materials. With this concept, a 10 kW thermal output power gasifier is designed and constructed. The gas and airflows can be converted to the air/fuel ratio, the most important aspect of gasifier operation. The air/fuel ratio shows operation in a combustion mode at start up, a gasification mode for the middle part of the run and a charcoal gasification mode at the end of the run. Since the interest here is exploring and validating of this concept, a bottom lit updraft gasifier is designed mainly to look at the gas yield and other favourable factors and to use this gas so obtained for thermal applications. The rate of feed was between 9 and 10 kg/h and continuous operation for 5 h was made in a couple of runs to study the performance. In this paper we report the salient features of our efforts and results, yielding a gasifier efficiency of 73%. 相似文献
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This paper introduces a directional filter bank (DFB) for segmentation of NDE images containing directional information. The DFB is used to split an image into a desired number of sub-band images with each sub-band image containing features belonging only to a given angular range. The DFB is a two-channel decomposition employing the Quincunx sampling matrix and the diamond half band filter pair. The DFB is also designed to incorporate the property of perfect reconstruction or alias free reconstruction. Applications of the DFB towards segmenting C-scan images of fiber-reinforced composites, magnetic flux leakage (MFL) images of seamless tubes, IR images of solar cell panels and optical images for the computation of area coverage in a shot-peening process are discussed. 相似文献
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Controllability of Fractional Order Stochastic Differential Inclusions with Fractional Brownian Motion in Finite Dimensional Space
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In this paper, sufficient conditions are formulated for controllability of fractional order stochastic differential inclusions with fractional Brownian motion (fBm) via fixed point theorems, namely the Bohnenblust-Karlin fixed point theorem for the convex case and the Covitz-Nadler fixed point theorem for the nonconvex case. The controllability Grammian matrix is defined by using Mittag-Leffler matrix function. Finally, a numerical example is presented to illustrate the efficiency of the obtained theoretical results. 相似文献
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In this paper, the problem of delay-dependent exponential stability for fuzzy recurrent neural networks with interval time-varying delay is investigated. The delay interval has been decomposed into multiple non equidistant subintervals, on these interval Lyapunov-Krasovskii functionals (LKFs) are constructed to study stability analysis. Employing these LKFs, an exponential stability criterion is proposed in terms of Linear Matrix Inequalities (LMIs) which can be easily solved by MATLAB LMI toolbox. Numerical example is given to illustrate the effectiveness of the proposed method. 相似文献
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Rathinasamy Sakthivel Thangavel Saravanakumar Murugesan Sathishkumar 《IET systems biology》2017,11(5):139
This study considers the problem of non‐fragile reliable control synthesis for mathematical model of interaction between the sugarcane borer (Diatraea saccharalis) and its egg parasitoid Trichogramma galloi. In particular, the control could be substituted by periodic releases of a small population of natural enemies and hence it is important to propose the time‐varying controller in sugarcane borer. The main aim of this study is to design a state feedback non‐fragile (time‐varying) reliable controller such that the states of the sugarcane borer system reach the equilibrium point within the desired period. A novel approach is proposed to deal with the uncertain matrices which appear in non‐fragile reliable control. Finally, simulations based on sugarcane borer systems are conducted to illustrate the advantages and effectiveness of the proposed design technique. The result reveals that the proposed non‐fragile control provides good performance in spite of periodic releases of a small population of natural enemies occurs.Inspec keywords: microorganisms, plant diseases, biology computing, state feedback, biocontrol, control system synthesisOther keywords: nonfragile reliable control synthesis, sugarcane borer, mathematical model, Diatraea saccharalis, egg parasitoid, Trichogramma galloi, periodic releases, natural enemies, state feedback nonfragile time‐varying reliable controller, equilibrium point, design technique 相似文献
10.
Gopal Gantala C. V. Krishnamurthy Krishnan Balasubramaniam 《Journal of Nondestructive Evaluation》2016,35(2):23
The inverse problem of reconstructing the location and size of defects in a coated metallic pipe from single frequency limited view electromagnetic scattered field is considered. Specifically, the paper addresses the problem of assessing shape changes in the shadow region entailed by limited view data in 2D by operating in an intermediate size parameter (ka) range. The inverse scattering problem is formulated as a non-linear optimization problem solved through genetic algorithm that seeks to minimize in the least-squared sense the difference between measured data and simulated data through iterations of the solution to a forward problem. The hybrid finite element boundary integral formulations were used to solve the forward problem of coated metallic pipe with defects. The proposed inversion methodology was applied for shadow region shape change assessment to determine whether a metal pipe is coated or not, and to reconstruct the location and size of corrosion-like defect, over a range of size parameters. The study is carried out using transverse electric and transverse magnetic polarized fields. To understand the effect of coating on backscattered fields, parametric studies are conducted using numerical data. A range for size parameter \(2.0\le ka\le 4\) was found to produce the highest contrast between defect free pipe and coated metallic pipes with defects in the deep shadow region. The experiments are carried out using vector network analyzer in an anechoic chamber. The inversion results obtained using measured data were found be in good agreement with inversion results obtained using synthetic data. Estimated extent of corrosion in deep shadow region of a coated metallic pipe was found to be within 9 % of actual extent of corrosion. 相似文献