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Cochin, India
Cochin, India
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Abraham J.,Mg University | Paul V.,CUSAT
Proceedings of 2016 International Conference on Data Mining and Advanced Computing, SAPIENCE 2016 | Year: 2016

This paper propose a simple method using DWT for fingerprinting digital images. Digital fingerprinting is used to detect the buyer or owner of digital resource. Algorithm presented locates regions that are insensitive to human vision so that presence of embedded identification code is fully concealed from the attention of the viewer. Frequency domain technique adopted improves the robustness of the scheme to various image processing attacks. The fingerprinting information is redundantly hidden to enable reliable detection even if the image is subjected to cropping or editing. © 2016 IEEE.


Mohanan P.,CUSAT
IEEE Region 10 Annual International Conference, Proceedings/TENCON | Year: 2017

Synthetic Aperture Radar (SAR) is a coherent microwave imaging method used for mapping scattering properties of Earth's surface. Speckle is a granular disturbance, modeled as a multiplicative noise, that affects all types of coherent images. Most of the applications demand speckle reduction to be carried out in real-time and require computationally simple and efficient techniques. The paper presents a combination of spatial and frequency domain techniques for removing speckle noise. The algorithm uses a Wiener filter as a preprocessing stage in the spatial domain and adaptive soft thresholding of Wavelet transform coefficients in the frequency domain. Considering multiplicative model for speckle noise, logarithmic transform is applied to Wiener filtered image. Threshold value at each decomposition level and subband is computed from the corresponding standard deviation. Simulation results show that the proposed method is efficient in removing speckle noise compared to an existing algorithm. The results are quantitatively analysed using Peak Signal-to-Noise Ratio (PSNR) and Structural SIMilarity (SSIM) metrics. © 2016 IEEE.


A multimode ratiometric Hg2+ selective chemosensor system based on a carbazole-thiobarbituric acid conjugate (CTBA) was developed. Its colorimetric and fluorescence behavior towards Hg2+ ions in both homogeneous and microheterogeneous media were investigated. A ratiometric mode of response of absorption as well as fluorescence in acetonitrile and 9:1 THF/H2O medium was observed in the presence of Hg2+ ions. The sensing mechanism involves formation of a 1:2 CTBA:Hg2+ complex by deprotonation of imide protons of the thiobarbituric acid unit. The complex formation can be reversed by using competing ligands such as cysteamine hydrochloride. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.


Raveenderan R.,CUSAT | Sujatha C.H.,CUSAT
Indian Journal of Marine Sciences | Year: 2011

Present study consists the quantization of specific metals-- Cr, Cd, Pb, Zn and Cu observed in the experimental bivalve, Villorita species. Bivalve specimens were collected seasonally from the identified three hot spots of Vembanad Lake. Soft tissue concentrations of metals are very sensitive in reflecting changes in the ambient environment and hence important in assessing the environmental quality. Concentrations of Zn in bivalves were fairly high compared to other metals. All the stations showed a maximum concentration during premonsoon and minimum during the other two seasons. Levels of Pb, Cu, Zn, Cd and Cr are between 0-6.17mg/kg, 0-17.224mg/kg, 1.916-255.163mg/kg, 0.325-4.133mg/kg, and 0-15.233mg/kg respectively.


We developed a multimode Hg2+ selective sensor system based on carbazole-barbituric acid conjugate (CBA). Its colorimetric and fluorescent behavior for Hg2+ ions in aqueous medium was investigated. Upon Hg2+ binding, CBA exhibited significant change in the absorption spectrum along with an enhanced emission at 593 nm. This allows the selective and sensitive detection of Hg2+ without any interference from other metal ions. © The Royal Society of Chemistry 2016.


Arun P.V.,CUSAT
Annals of GIS | Year: 2013

Visualization of geospatial entities generally adopts digital elevation models (DEMs) that are interpolated to establish 3D co-ordinates for the entire terrain. The accuracy of the generated terrain models depends on the type of interpolation mechanism adopted. Generally available methods in this context use point data values and their distribution; however, terrain characteristics such as shape are not generally considered in the interpolation. We propose an adaptive interpolation strategy that considers the terrain features for improving the estimation accuracy. In this research, we have compared the proposed approach with different contemporary interpolation techniques, such as inverse distance weighting, kriging (KRG), nearest neighbour and spline methods. Comparative analysis of the proposed technique with contemporary approaches revealed that considerable success has been achieved with the procedure. Investigations have also been done to analyse the sensitivity of the approach to terrain smoothness. © 2013 Taylor & Francis Group.


Sivaprasad K.,CUSAT | Krishnan C.G.G.,ALE Heavylift Middle East LLC
RINA, Royal Institution of Naval Architects - International Conference on Ship and Offshore Technology, ICSOT India 2015: Coastal and Inland Shipping | Year: 2015

Being The God's own Country, the State of Kerala has large number of inland water bodies including inland waterways, Canals, Back Waters, Rivers and Reservoirs which offer good potential for water borne passenger and cargo transport, cruise tourism, recreational and sports boating. Among these slow speed cruises using small boats is a potential area in the tourism sector. Slow speed boats running on solar power is emerging as the most feasible and practical solution. Solar powered vessels can be a considered as a best answer to the energy crisis imposed by the ever depleting fossil fuel resources and the best way out to minimize the negative impact on the environment caused by the discharge of fuel to the water bodies and emissions from the engines. Not only are these an expense to the environment, but are ambient and healthier by the Traditional nature of the architecture involved in the design. The Paper introduces the concept of a "Nallukettumaran"- A Catamaran Houseboat with a Nallukettu Style of Architecture where the roofs are surmounted solar panels thus ensuring cleaner energy, and healthy cruising. There is also a moonpool beneath the Nallukettu, which offers recreation, thus creating a revolution in Inland Water transport, and tourism by effectively tapping cleaner energy. lessons of simplicity and healthiness, evolved through time, which we can't be negotiated. Laurie Baker, the legend of architecture for the poor has hailed the style of Architecture in Kerala for its sustainability. © 2015: The Royal Institution of Naval Architects.


Sunilkumar M.,National Institute of Technology Calicut | Francis T.,St. Joseph's College | Thachil E.T.,CUSAT | Sujith A.,National Institute of Technology Calicut
Chemical Engineering Journal | Year: 2012

In recent years, there has been a marked increase in the interest in biodegradable polymer materials for the use in packaging, agriculture, medicine, and other areas. Biodegradable composite films has been fabricated, via peroxide initiated melt-compounding process, by blending low density polyethylene (LDPE) and chitosan, in a rotor disperser. Chitosan, maleic anhydride (MA), dicumyl peroxides (DCP) and oleic acid constituent in palm oil have been used as biodegradable filler, coupling agent, free radical initiator and Lewis acid catalyst, respectively. The palm oil serves the additional function of a plasticizer as indicated by the mechanical property studies. The hydrophilicity, thermal, biodegradablity and dielectric properties of the biocomposite system have also been investigated. Biodegradability of the samples has been studied by inoculating the films with Aspergillus niger (A. niger) on a potato dextrose agar media and incubated at surrounding temperature (25 °C) for 21. days. After incubation, the films were again subjected to morphological and tensile studies. Hydrophilicity and biodegradation rate has been found to increase with increase in chitosan loading in the matrix. The plasticized samples showed better biodegradablity rate and hydrophilicity compared to the unplasticized ones. The addition of palm oil retains the thermal stability of the present biocomposite film. Chitosan and palm oil hybrid reinforced LDPE has proved to be a novel combination with increased biodegradable rate of LDPE. The improved dielectric property of the composite has also enhanced the antibacterial properties. The tailor-made biodegradable plastic film proves to be eco-friendly alternatives to synthetic plastics and have invoked potential applications in food-packaging, bio-separations and drug delivery. © 2012 Elsevier B.V.


George S.,Indian National Institute for Interdisciplinary Science and Technology | Sebastian M.T.,Indian National Institute for Interdisciplinary Science and Technology | Raman S.,CUSAT | Mohanan P.,CUSAT
International Journal of Applied Ceramic Technology | Year: 2011

New low-temperature sinterable dielectric materials based on Li 2CaSiO4 (LCS) ceramic has been developed. The LCS ceramics were prepared by solid-state ceramic route. The calcination and sintering temperatures of LCS were optimized as 800°C/4 h and 1000°C/2 h, respectively, for the best density and dielectric properties. The dielectric properties of the ceramic were measured in the radio frequency by parallel plate capacitor method and in the microwave frequency range by cavity perturbation technique. The LCS sintered at 1000°C/2 h had εr=4.36 and tan δ=0.003 at 8 GHz. The sintering temperature of LCS is lowered from 1000°C to 850°C/2 h for low-temperature co-fired ceramic application by the addition of different borosilicate glasses with reasonably good microwave dielectric properties. The stability of the glass-ceramic composites with temperature was also investigated. © 2009 The American Ceramic Society.


Arun P.V.,CUSAT
Forest Science and Technology | Year: 2014

Remote sensing satellite images are effectively used as a tool for decision making in various fields, especially in forest management and related analyses. Different geospatial parameters are required for effective decision making and the possibility of an integrated framework for automation of various analyses has been investigated. Advanced web mining and intelligent techniques have been adopted for the development of a comprehensive open-source framework for this purpose. The effectiveness of the developed methodology has been discussed and illustrated with reference to study areas using various statistical parameters. Adoption of a cellular neural network (CNN) for feature modeling and open-source data for automatic mining seemed to be effective. The developed methodologies were found to outperform existing ones with regard to accuracy and complexity. Investigations revealed that use of CNN is very effective in shape modeling, and improves accuracy of detection. © 2014 © 2014 Korean Forest Society.

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