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Thanjāvūr, India

Manikandan A.,Presidency College at Chennai | Durka M.,AVVM Sri Pushpam College | Arul Antony S.,Presidency College at Chennai
Journal of Superconductivity and Novel Magnetism | Year: 2014

Spinel MnxCo1−xAl2O4 (x = 0, 0.3, and 0.5) nanoparticles were synthesized by a simple microwave-assisted combustion method. Powder X-ray diffraction (XRD) analysis was confirmed the formation of single phase, cubic spinel structure without other impurities. Average crystallite sizes of the samples were found to be in the range of 10.12 nm to 1623 nm by Scherrer’s method. FT-IR spectra showed the stretching frequencies corresponding to the M–Al–O bond of spinel structure. High-resolution scanning electron microscope (HR-SEM) and high-resolution transmission electron microscope (HR-TEM) images showed the particle-like nanostructures. Band gap energy was estimated using UV-Visible DRS spectra and the values are increased with increasing Mn2+ content (345 eV to 3.75 eV). Vibrating sample magnetometer (VSM) measurements revealed that pure and Mn-doped CoAl2O4 samples have ferromagnetic behavior and the magnetization values increased with increasing the concentration of Mn2+ ions in the CoAl2O4lattice. Catalytic oxidation of benzyl alcohol into benzaldehyde was found that the sample Mn0.5Co0.5Al2O4showed 96.58 % conversion with 100 % selectivity, whereas pure CoAl2O4, the conversion was only 87.43 % with 100 % selectivity. © 2014, Springer Science+Business Media New York. Source

Baraniraj T.,Thanthai Hans Roever College | Philominathan P.,AVVM Sri Pushpam College
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2010

Single crystals of l-arginine maleate dihydrate (LAMD) were successfully grown from aqueous solution by solvent evaporation technique. As-grown crystals were analyzed by different instrumentation techniques such as X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectra and UV-vis near infrared (NIR) transmittance spectra. Thermal behavior has been studied with TGA/DTA analyses. The optical second harmonic generation (SHG) conversion efficiency of LAMD was determined using Kurtz powder technique and found to be 1.5 times that of KDP. © 2009 Elsevier B.V. All rights reserved. Source

Srinivasan S.,Cauvery College for Women | Ramakrishnan S.,AVVM Sri Pushpam College
Computing | Year: 2013

Cultural algorithms (CA) use social intelligence to solve problems in optimization. The CA is a class of evolutionary computational models inspired from observing the cultural evolutionary process in nature. Cultural algorithms employ a basic set of knowledge sources, each related to knowledge observed in various animal species. Knowledge from these sources is then combined to influence the decisions of the individual agents in solving problems. Classification using "IF-THEN" rules comes under descriptive knowledge discovery in data mining and is the most sought out by users since they represent highly comprehensible form of knowledge. The rules have certain properties which make them useful forms of actionable knowledge to the users. The rules are evaluated using these properties represented as objective and subjective measures. The rule properties may be conflicting. Hence discovery of rules with specific properties is considered as a multi-objective optimization problem. In the current study an extended cultural algorithm which applies social intelligence in the data mining domain to present users with a set of rules optimized according to user specified metrics is proposed. Preliminary experimental results using benchmark data sets reveal that the algorithm is promising in producing rules with specific properties. © 2012 Springer-Verlag Wien. Source

Kumar M.S.,Oman Dental College | Philominathan P.,AVVM Sri Pushpam College
International Journal of Automation and Computing | Year: 2012

Purcell's swimmer was proposed by E. M. Purcell to explain bacterial swimming motions. It has been proved experimentally that a swimmer of this kind is possible under inertial-less and high viscous environment. But we could not investigate all the aspects of this mechanism through experiments due to practical difficulties. The computational fluid dynamics (CFD) provides complementary methods to experimental fluid dynamics. In particular, these methods offer the means of testing theoretical advances for conditions unavailable experimentally. Using such methodology, we have investigated the fluid dynamics of force production associated with the Purcell's swimmer. By employing dynamic mesh and user-defined functions, we have computed the transient flow around the swimmer for various stroke angles. Our simulations capture the bidirectional swimming property successfully and are in agreement with existing theoretical and experimental results. To our knowledge, this is the first CFD study which shows the fact that swimming direction depends on stroke angle. We also prove that for small flapping frequencies, swimming direction can also be altered by changing frequency-showing breakdown of Stokes law with inertia. © 2012 Institute of Automation, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg. Source

Srinivasan S.,AVVM Sri Pushpam College | Ramakrishnan S.,AVVM Sri Pushpam College
Artificial Intelligence Review | Year: 2011

Evolutionary multi objective optimization (EMOO) systems are evolutionary systems which are used for optimizing various measures of the evolving system. Rule mining has gained attention in the knowledge discovery literature. The problem of discovering rules with specific properties is treated as a multi objective optimization problem. The objectives to be optimized being the metrics like accuracy, comprehensibility, surprisingness, novelty to name a few. There are a variety of EMOO algorithms in the literature. The performance of these EMOO algorithms is influenced by various characteristics including evolutionary technique used, chromosome representation, parameters like population size, number of generations, crossover rate, mutation rate, stopping criteria, Reproduction operators used, objectives taken for optimization, the fitness function used, optimization strategy, the type of data, number of class attributes and the area of application. This study reviews EMOO systems taking the above criteria into consideration. There are other hybridization strategies like use of intelligent agents, fuzzification, meta data and meta heuristics, parallelization, interactiveness with the user, visualization, etc., which further enhance the performance and usability of the system. Genetic Algorithms (GAs) and Genetic Programming (GPs) are two widely used evolutionary strategies for rule knowledge discovery in Data mining. Thus the proposed study aims at studying the various characteristics of the EMOO systems taking into consideration the two evolutionary strategies of Genetic Algorithm and Genetic programming. © 2011 Springer Science+Business Media B.V. Source

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