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991.
Emad E. Abdallah A. Ben Hamza Prabir Bhattacharya 《Signal, Image and Video Processing》2010,4(2):233-245
We present a robust, hybrid non-blind MPEG video watermarking technique based on a high-order tensor singular value decomposition
and the discrete wavelet transform (DWT). The core idea behind our proposed technique is to use the scene change analysis
to embed the watermark repeatedly into the singular values of high-order tensors computed form the DWT coefficients of selected
frames of each scene. Experimental results on video sequences are presented to illustrate the effectiveness of the proposed
approach in terms of perceptual invisibility and robustness against attacks. 相似文献
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Plasmonic Lipid Bilayer Membranes for Enhanced Detection Sensitivity of Biolabeling Fluorophores
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Rupak Bhattacharya Chaitanya Indukuri Nafisa Begam Oliver H. Seeck Jaydeep K. Basu 《Advanced functional materials》2015,25(46):7233-7242
Plasmonics based sensing, using the surface plasmon resonance of metal nanoparticles, has been effectively demonstrated in various applications. Extending this methodology to cell and artificial lipid bilayer membranes is extremely beneficial in enhancing the sensitivity of the detection of binding and cellular transport of molecules across such membranes. Here, the creation of an artificial plasmonic biomembrane template is demonstrated and used to show the enhanced detection sensitivity of certain widely used biomarker molecules. The efficacy of these templates is explained in terms of the ability of the hydrophobic polymer grafted gold nanoparticles used to organize, penetrate, and fluidize the membranes. The enhancement of photoluminescence of the dye molecules used occurs over a reasonably large spectral range as compared to the plasmon resonance of gold nanoparticles. The results could, possibly, be extended to cellular membranes with relevant modifications, as well as to the detection of any other biological molecule appropriately labeled with fluorescent dye molecules, and demonstrate the versatility of these plasmonic bioinspired platforms as potential biochemical sensors. 相似文献
994.
G. P. Dinda A. K. Dasgupta S. Bhattacharya H. Natu B. Dutta J. Mazumder 《Metallurgical and Materials Transactions A》2013,44(5):2233-2242
Direct metal deposition (DMD) technology is a laser-aided rapid prototyping method that can be used to fabricate near net shape components from their CAD files. In the present study, a series of Al-Si samples have been deposited by DMD in order to optimize the laser deposition parameters to produce high quality deposit with minimum porosity and maximum deposition rate. This paper presents the microstructural evolution of the as-deposited Al 4047 sample produced with optimized process parameters. Optical, scanning, and transmission electron microscopes have been employed to characterize the microstructure of the deposit. The electron backscattered diffraction method was used to investigate the grain size distribution, grain boundary misorientation, and texture of the deposits. Metallographic investigation revealed that the microstructural morphology strongly varies with the location of the deposit. The layer boundaries consist of equiaxed Si particles distributed in the Al matrix. However, a systematic transition from columnar Al dendrites to equiaxed dendrites has been observed in each layer. The observed variation of the microstructure was correlated with the thermal history and local cooling rate of the melt pool. 相似文献
995.
Bayan A. Mahdi Amrik Bhattacharya Anshu Gupta 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(3):418-426
BACKGROUND: Sal (Shorea robusta) deoiled seed cake extract (SDOCE) was assessed for its suitability as a cheap natural substrate for lipase production under submerged fermentation. The bacterial isolate Aeromonas sp. S1 isolated from dairy industry was used for lipase production. Both the isolate and its lipase were shown to be potential tools for treatment of dairy wastewater containing higher organic load. RESULTS: On substituting tributyrin with SDOCE, lipase production was enhanced 24‐fold (195 U mL?1) compared with the initial 8.13 U mL?1 lipase activity. Maximum lipase production was obtained at pH 8.0 and incubation temperature 30 °C. The lipase had pH and temperature optima of 10.0 and 55 °C, respectively. The isolate and its crude enzyme preparation were checked separately for applicability in dairy wastewater treatment. The isolate was able to reduce chemical oxygen demand (COD) by 93%, oil and grease (O&G) by 75%, and total suspended solids (TSS) by 47% after 96 h of treatment. Enzymatic preparation gave 86% reduction of COD after 12 h and 75 and 45% reduction of O&G and TSS, respectively, after 96 h of treatment. CONCLUSION: Overall, the study shows the usefulness of Sal seed deoiled cake, a cheap agro‐industrial by‐product for the production of lipase. The isolate and its lipase can also be used effectively for the treatment of dairy wastewater. Copyright © 2011 Society of Chemical Industry 相似文献
996.
Safikul Alam S Chandra Sourabh Bhattacharya Swapan 《Wireless Personal Communications》2018,103(2):1535-1562
Wireless Personal Communications - In this paper, we propose a new optimal framework with repair strategy to resolve major issues in the assignment of resources to mobile terminals (plainly to... 相似文献
997.
Samyadeb Bhattacharya Subhashish Banerjee Arun Kumar Pati 《Quantum Information Processing》2018,17(9):236
A master equation has been constructed for a global system–bath interaction in the both absence and presence of non-Markovian noise. For the memoryless case, it has been exactly solved for a paradigmatic class of two qubit states in high- and zero-temperature thermal environment. For the non-Markovian model, it has been solved for zero-temperature bath. The evolution of quantum coherence and entanglement has been observed in the presence of the above-mentioned interactions. We show that the global part of the system–bath interaction compensates for the decoherence, resulting in slowdown of coherence and entanglement decay. For an appropriately defined limiting case, both coherence and entanglement show freezing behavior for the high-temperature bath. In case of zero-temperature bath, the mentioned interaction not only stabilizes the non-classical correlations, but also enhances them for a finite period. For the memory-dependent case, we have seen that the global interaction enhances the backflow of information from environment to the system, as it enhances the regeneration of coherence and entanglement. Also we have studied the generation of quantum Fisher information by the mentioned process. An intuitive measure of non-classicality based on non-commutativity of quantum states has been considered. Bounds on generated quantum Fisher information have been found in terms of quantumness and coherence. This gives us a novel understanding of quantum Fisher information as a measure of non-classicality. 相似文献
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Robert C. Pullar Igor K. BdikinAshok K. Bhattacharya 《Journal of the European Ceramic Society》2012,32(4):905-913
The microstructure and magnetic properties of randomly oriented BaFe12O19, SrFe12O19, Ba2Co2Fe12O22, Ba3Co2Fe24O41, Ba3Ca0.3Co2Fe24O41 and BaCo2Fe16O27 hexaferrite fibres were characterised. 2D and 3D AFM and MFM images were taken of a single BaM fibre. Magnetic properties of random ferrite fibres compared well to expected values for polycrystalline ceramics. The little-characterised Co2W ferrite was found to have Ms and Hc similar to that of Co2Z. Relatively small applied fields of <0.05 T were required to reverse the magnetisation of all the soft hexaplana ferrite fibres, and all had Hc < 40 kA/m, becoming demagnetised in fields <0.025 T. Random Co2W fibres had a high Mr/Ms ratio of 0.56, (greater than M ferrites), despite being very magnetically soft (low coercivity), due to the unusual “lobed” shape of their hysteresis loop, which was attributed to their fibrous nature, and elongated growth of the grains along the fibre axis. Co2Z had the lowest Hc of all the ferroxplana fibres. 相似文献