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Hashmi S. A. Bhat Md Yasir Singh Manoj K. Sundaram N. T. Kalyana Raghupathy Bala P. C. Tanaka Hideaki 《Journal of Solid State Electrochemistry》2016,20(10):2817-2826
Journal of Solid State Electrochemistry - We report the studies on composite gel polymer electrolytes (GPEs) comprising 0.5 M solution of sodium trifluoromethane sulfonate (Na-triflate or... 相似文献
73.
The advances in recording, editing, and broadcasting multimedia contents in digital form motivate to protect these digital contents from illegal use, such as duplication, manipulation, and redistribution. However, watermarking algorithms are designed to satisfy requirements of applications, as different applications have different concerns. We intend to design a watermarking algorithm for applications which require high embedding capacity and imperceptibility, to maintain the integrity of the host signal as well as embedded information. Reversible watermarking is a promising technique which satisfies our requirements. In this paper, we concentrate on improving the watermark capacity and reducing the perceptual degradation of an image. We investigated the Luo's [1] additive interpolation-error expansion algorithm and enhanced it by incorporating with two intelligent techniques: genetic algorithm (GA), and particle swarm optimization (PSO). Genetic algorithm is applied to exploit the correlation of image pixel values to obtain better estimation of neighboring pixel values, which results in optimal balance between information storage capacity and imperceptibility. Particle swarm optimization (intelligent technique) is also applied for the same purpose. Experimental results show that PSO and GA nearly give the same results, but GA outperforms the PSO. Experimental results also reveal that the proposed strategy outperforms the state of art works in terms of perceptual quality and watermarking payload. 相似文献
74.
Fingerprint image enhancement using multi-scale DDFB based diffusion filters and modified Hong filters 总被引:1,自引:0,他引:1
The main task of a fingerprint image enhancement is to enhance the image in such a way that it not only remove the noise but also enhance the reliable minutiae points. For this purpose, in this paper we propose a multi-scale decimation-free directional filter bank method for reliable orientation estimation. This reliable orientation is used in coherence enhancement diffusion and in Gabor filter based enhancement, which overcomes the drawbacks of these two methods. Experimental results show that the proposed method not only enhances the images but also facilitates the minutiae algorithm, by enhancing the true minutiae points. 相似文献
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Yasir Khan Qingbiao Wu Naeem Faraz A. Yildirim M. Madani 《Applied Mathematics Letters》2012,25(10):1340-1346
This work suggests a new analytical technique called the fractional homotopy perturbation method (FHPM) for solving fractional differential equations of any fractional order. This method is based on He’s homotopy perturbation method and the modified Riemann–Liouville derivative. The fractional differential equations are described in Jumarie’s sense. The results from introducing a modified Riemann–Liouville derivative in the cases studied show the high accuracy, simplicity and efficiency of the approach. 相似文献
77.
Khalid Rehman Hakeem Faheema Khan Ruby Chandna Tariq Omer Siddiqui Muhammad Iqbal 《Applied biochemistry and biotechnology》2012,168(8):2309-2329
The present investigation was conducted to evaluate salt tolerance in ten genotypes of soybean (Glycine max L.). Twelve-day-old seedlings, grown hydroponically, were treated with 0, 25, 50, 75, 100, 125 and 150?mM NaCl for 10?days. Growth, lipid peroxidation and antioxidant enzyme activities were evaluated. Growth, measured in terms of length, fresh weight and dry weight of plants, was drastically reduced in Pusa-24 while there was little effect of NaCl treatment on Pusa-37 genotype of soybean. High level of lipid peroxidation was observed in Pusa-24 as indicated by increased level of malondialdehyde. Activities of superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase were maximum in Pusa-37 where 9-, 1-, 5- and 6-fold increase over control were observed, respectively. The results suggested that Pusa-24 and Pusa-37 are salt-sensitive and salt-tolerant genotype of soybean, respectively, and antioxidant defence system is involved in conferring the sensitiveness and tolerance in these genotypes. Salt-tolerant genotype Pusa-37, was further analysed by 2-dimensional gel electrophoresis to analyse the differential expression of proteins at high salt stress. In the present study, 173 protein spots were identified. Of these, 40 proteins were responsive to salinity in that they were either up- or downregulated. This study could help us in identifying the possible regulatory switches (gene/s) controlling novel proteins of the salt-tolerant genotype of the crop plants and their possible role in defence mechanism. 相似文献
78.
Tariq M Freire MG Saramago B Coutinho JA Lopes JN Rebelo LP 《Chemical Society reviews》2012,41(2):829-868
Some of the most active scientific research fronts of the past decade are centered on ionic liquids. These fluids present characteristic surface behavior and distinctive trends of their surface tension versus temperature. One way to explore and understand their unique nature is to study their surface properties. This critical review analyses most of the surface tension data reported between 2001 and 2010 (187 references). 相似文献
79.
Production of high performance conductive textile yarn fibers for different electronic applications has become a prominent area of many research groups throughout the world. We have used oxidative chemical vapor deposition (OCVD) technique to coat flexible and high strength polyester yarns with conjugated polymer, poly(3,4‐ethylenedioxythiophene) (PEDOT) in presence of ferric (III) chloride (FeCl3) oxidant. OCVD is an efficient solvent free technique used to get uniform, thin, and highly conductive polymer layers on different substrates. In this paper, PEDOT‐coated polyester (PET) yarns were prepared under specific reaction conditions, and the electrical, mechanical and thermal properties were compared to previously studied PEDOT‐coated viscose yarns. Scanning electron microscopy (SEM) and FT‐IR analysis revealed that polymerization of PEDOT on the surface of the polyester yarns has been taken place successfully and structural analysis showed that PEDOT has strong interactions with viscose yarns as compared to PET yarns. The voltage–current (V–I) characteristics showed that PET yarns are more conductive than PEDOT‐coated viscose yarns. The variation in the conductivity of PEDOT‐coated yarns and the heat generation properties during the flow of current through coated yarns for longer period of time, was studied by time–current (t–I) characteristics. Thermogravimeteric analysis (TGA) was employed to investigate the thermal properties and the amount of PEDOT in PEDOT‐coated PET yarns compared to PEDOT‐coated viscose. The effect of PEDOT coating and ferric (III) chloride concentration on the mechanical properties of coated yarns was evaluated by tensile testing. The obtained PEDOT‐coated conductive polyester yarns could be used in smart clothing for medical and military applications. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
80.