Chellatamilan T.,Arunai Engineering College |
Suresh R.M.,Sri Muthukumaran Institute of Technology
Life Science Journal | Year: 2013
With the advent of internet technology as a ubiquitous platform for sharing the educational contents and experiences, many of the institutions across the globe offer the federated search to the courses, lesson plans, contents, assignments, seminars and experiments. These learning resources are stored in the repositories of the learning content management system. Sophisticated search and information retrieval solutions are essential for efficient use of these repositories. The structure of many existing information retrieval system considers ontology for retrieval. This ontology based solution increases the accuracy of information retrieval through high precision and recall. This paper addresses the requirement for pre-processing and classification of documents in order to achieve more efficient Information Retrieval system. Tools and techniques employed for autonomous classification or clustering of documents are investigated and a new method based on concept expansion is proposed. The proposed methods are evaluated using Reuters 21578 dataset.
Jayakumar L.,Arunai Engineering College |
Balamurugan K.,Indian Institute of Road and Transport Technology |
Ezilarasan C.,SMK Fomra Institute of Technology
International Review of Mechanical Engineering | Year: 2014
The wear and friction behaviour of 7075 Al-25(wt %) SiC particle composite were investigated at a speed range of 3 to 9 m/s and load range of 30 to 110 N using pin-on-disc wear testing machine. In this work, the automobile friction material was used as pin and the composite as counter face and the results were compared with the commercially used cast iron brake disc. The results show that the wear rate of the Al MMC disc was less than that of the conventional cast iron disc. The coefficient of friction decreases with increase of applied load for both cast iron and Al MMC materials. However, the friction coefficient of Al MMC is higher than that of the cast iron. In all tests it is observed that the wear rate of friction material was more when sliding against MMC disc because of the abrasive action of fractured and pulled out SiC particles. The wear grooves formed on the cast iron disc, MMC disc and friction material have been analysed using optical micrographs and X- ray diffraction (XRD) technique. © 2014 Praise Worthy Prize S.r.l. - All rights reserved.
Balamurugan C.R.,Arunai Engineering College |
Natarajan S.P.,Annamalai University |
Shanthi B.,Annamalai University
International Review of Electrical Engineering | Year: 2013
This paper presents the comparison of unipolar multicarrier Pulse Width Modulation (PWM) techniques for the Cascaded Multi Level Inverter (CMLI). Due to switch combination redundancies, there are certain degrees of freedom to generate the five level AC output voltage. This paper presents the use of Control Freedom Degree (CFD) combination. The effectiveness of the PWM strategies developed using CFD are demonstrated by simulation and experimentation. The simulation results indicate that the chosen five level inverter triggered by the developed UISCPSPWM and UISCVFPWM strategy with sine and stepped wave references and UISCAPODPWM strategy with THI PWM and 60 degree reference exhibis reduced harmonics. UISCCOPWM provides higher fundamental RMS output voltage for all four chosen references. PWM strategies developed are implemented in real time using dSPACE/Real Time Interface (RTI). The simulation and experimental outputs closely match with each other validating the strategies presented. © 2013 Praise Worthy Prize S.r.l. - All rights reserved.
Lakshmipathy J.,Arunai Engineering College |
Kulendran B.,Indian Institute of Road and Transport Technology
International Journal of Refractory Metals and Hard Materials | Year: 2014
In the present study, the reciprocating wear behavior of 7075Al/SiC composites and 6061Al/Al2O3 composites that are prepared through liquid metallurgy route is analyzed to find out the effects of weight percentage of reinforcement and load at the fixed number of strokes on a reciprocating wear testing machine. The Metal Matrix Composite (MMC) pins are prepared with different weight percentages (10, 15 and 20%) of SiC and Al 2O3 particles with size of 36 μm. Hardness of these composites increases with increase in wt.% of reinforcement. However, the impact strength decreases with increase in reinforcement content. The experimental result shows that the volume loss of MMC specimens is less than that of the matrix alloy. However, the volume loss is greater in 6061Al/Al2O 3 composites when compared to 7075Al/SiC composites. The temperature rise near the contact surface of the MMC specimens increases with increase in wt.% of reinforcement and applied load. The coefficient of friction decreases with increase in load in both cases. © 2014 Elsevier Ltd.
Anitha K.,Arunai Engineering College |
Varugheese D.K.,Karpagam College of Engineering |
Muniraj N.J.R.,Karpagam College of Engineering
European Journal of Scientific Research | Year: 2012
As we move in to the future there is a rising demand for high performance, high capacity and high bit rate wireless communication systems to integrate wide variety of communication services such as high-speed data, video and multimedia traffic. In an OFDM scheme, a large number of orthogonal, overlapping, narrow band sub-channels or subcarriers, transmitted in parallel, divide the available transmission bandwidth. The separation of the subcarriers is theoretically minimal such that there is a very compact spectral utilization. DWT is faster than FFT hence it's replaced by transform technique for OFDM. This project proposes new adaptive fast lifting technique for both designing wavelets and performing the discrete wavelet transform. By implementing LDWT, it is able to increase the spectral efficiency and also decrease the bit error rate. This paper presents a performance measure of mean squared error by using lifting wavelet transform. The simulation results, the proposed approach displays a good reduction in mean squared error, comparison with the different types of wavelets. A modified DWT architecture for OFDM is designed and implemented on FPGA, the modified DWT-IDWT is modeled using HDL and synthesized using Xilinx ISE. The developed HDL design operates at 125MHz and consumes power of less than 1W on VIrtex-5 FPGA. © EuroJournals Publishing, Inc. 2012.