iosr-JCE   Volume-8 ~ Issue-2

Paper Type	:	Research Paper
Title	:	THD Reduction in Multilevel Inverters Using Real-Time Algorithm
Country	:	India
Authors	:	Megha Jess Mathew
	:	10.9790/0661-0820112

Abstract:Multilevel inverters have been widely applied industries. A family of optimal puisewidth modulation (PWM) methods for multilevel inverters, such as step modulation, can generate output voltage with less harmonic distortion than popular modulation strategies, such as the carrier-based sinusoidal PWM or the space vector PWM. However, some drawbacks limit the application of optimal PWM. One of such crucial drawback is that the optimal switching angles could not be calculated in real-time and one has to rely on lookup tables with precalculated angles. We propose a novel real-time algorithm for calculating switching angles that minimizes total harmonic distortion (THD) for step modulation. We give a mathematical proof that the output voltage has the minimum THD. We implemented the algorithm on a digital signal processor and provide experimental results that verify the performance of the proposed algorithm.
Keywords: Multilevel inverter, optimal puisewidth modulation (PWM), power conversion, Total Harmonic Distortion (THD), Digital Signal Processing (DSP).

[1] J. Rodriguez, J.-S. Lai, and F. Z. Peng, ―Multilevel inverters: A survey of topologies, controls, and applications.‖ IEEE Trans. Ind. Electron., vol. 49, no. 4, pp. 724-738, Aug. 2002.
[2] J. M. Carrasco, L. G. Franquelo, J. T. Bialasiewicz, E. Galvan, R. C. PortilloGuisado, M. A. M. Prats, J. i. Leon, and N. Moreno-
Alfonso, ―Power-electronic systems for the grid integration of renewable energy sources: A survey," IEEE Trans. Ind. Electron., vol.
53, no. 4, pp. 1002-1016, Jun. 2006.
[3] X. Xu, Y. Zou, K. Ding, and F. Liu, ―Cascade multilevel inverter with phase-shift SPWM and its application in STATCOM,‖ in Proc. IEEE 1ECON, 2004, vol. 2, pp. 1139-1143.
[4] Y. Liang and C. O. Nwankpa, "A new type of STATCOM based on cascading voltage-source inverters with phase-shifted unipolar
SPWM,‖ IEEE Trans. Ind. Appl., vol. 35, no. 5, pp. 1118-1123, Sep/Oct. 1999.
[5] J. Rodriguez, J. Pontt, P. Correa, P. Cortes, and C. Silva, "A new modu-vJ‟lation method to reduce common-mode voltages in multilevel inverters,‖ IEEE Trans. Ind. Electron., vol. 51, no. 4, pp. 834-839, Aug. 2004.
[6] S. Lakshminarayanan, G. Mondal, P. N. Tekwani, K. K. Mohapatra, Sn*^ and K. Gopakumar, ―Twelve-sided polygonal voltage space vector based multilevel inverter for an induction motor drive with common-mode voltage elimination,‖ IEEE Trans. Ind. Electron., vol. 54, no. 5, pp. 276i-2768, Oct. 2007.
[7] S. Sirisukprasert, J.-S. Lai, and T.-H. Liu, "Optimum harmonic reduction with a wide range of modulation indexes for multilevel
converters,‖ IEEE Trans. Ind. Electron., vol. 49, no. 4, pp. 875-881, Aug. 2002.
[8] L. M. Tolbert, F. Z. Peng, and T. G. Habetler, ―Multilevel converters for large electric drives,‖ IEEE Trans. Ind. Appl., vol. 35, no. 1, pp. 36-44, ,Jan./Feb. 1999.
[9] C. Rech and J. R. Pinheiro, ―Hybrid multilevel converters: Unified analysis and design considerations,‖ IEEE Trans. Ind. Electron., vol. 54, no. 2, pp. 1092-1104, Apr. 2007.
[10] Y. Liu and F. Luo, "Trinary hybrid multilevel inverter used in STATCOM with unbalanced voltages," Proc. Inst. Electr. Eng.—Elect. Power Appl., vol. 152, no. 5, pp. 1203-1222, Sep. 2005.

Paper Type	:	Research Paper
Title	:	RankingFor Web Databases Using SVM and K-Means algorithm
Country	:	India
Authors	:	P.Ayyadurai, S.Jayanthi
	:	10.9790/0661-0821318

Abstract:The Usage of internet in now a day is more and it became necessity for the people to do some applications such as searching web data bases in domains like Animation, vehicles, Movie, Real estates, etc. One of the problems in this context is ranking the results of a user query information. Earlier approaches problem have toused frequencies of database value regions, handling query logs, and user profiles information. A common thread in most of these approaches is that ranking is done in a usage page ranking manner. This paper simulates the usage of ranking query results based on user and query Dependent ranks by taking user and query similarities as input including the workload. K- Means algorithm used for cluster and re ranking process, multiple database system used for clustering the data. Among rank learning methods, ranking SVM has been favorably applied to various applications, e.g., optimizing search engine for web information, improving data retrieval quality. We define these similarities formally in discuss their effectiveness analytically and experimentally over four distinct web databases.
Keywords: Automated Ranking, Animation Database, Vehicle and Movie Databases, User similarity, Query similarity, workload.

[1] AdityaTelang, Chengkai Li, and Sharma Chakravarthy. ―One Size Does Not Fit All: Toward User- and Query-Dependent Ranking
for Web Databases; IEEE Transactions On Knowledge And Data Engineering, Vol. 24, No. 9, September 2012.
[2] Alex Penev, Raymond K. Wong; Finding Similar Pages in a Social Tagging Repository;WWW 2008,April 21–25, 2008, Beijing,
China. ACM 978-1-60558-085-2/08/04.
[3] Cynthia Dwork, Ravi Kumar, MoniNaor, D. Sivakumar; Rank Aggregation Methods for the Web;WWW10,May 1-5, 2001, Hong
Kong. ACM 1-58113-348-0/01/0005.
[4] Hwanjo Yu, Youngdae Kim, and SeungwonHwang.RV-SVM: An Efficient Method for Learning Ranking SVM;Korea Research
Foundation Grant funded by the Korean Government(KRF-2008-314-D00483)2009.
[5] KaushikChakrabarti, SurajitChaudhuri, Seung-won Hwang; Automatic Categorization of Query Results;SIGMOD 2004, June 13–
18, 2004, Paris, France.
[6] Marko balabanovic, yoavshoham. Content based, collaborative Recommendation; March 1997/Vol. 40, No. 3 Communication Of
The ACM.

[7] SurajitChadhuri, Gautam Das, VagelisHristidis; Probabilistic Information Retrieval Approach for Ranking of Database Query
Results; ACM Transactions on Database Systems, Vol. 31, No. 3, September 2006, Pages 1134–1168.
[8] SubbaraoKambhampati, Garrett Wolf, Yi Chen, HemalKhatriBhaumikChokshi, Jianchun Fan, UllasNambiar; QUIC: Handling
Query Imprecision & Data Incompleteness; in Autonomous Databases;(http://creativecommons.org/licenses/by/2.5/) CIDR 2007.
[9] Tapas Kanungo, Senior Member, IEEE, David M. Mount, Member, IEEE, Nathan S. Netanyahu, Member, IEEE, Christine D.
Piatko, Ruth Silverman, and Angela; An Efficient C-Means Clustering Algorithm: Analysis and Implementation; IEEE
Transactions On Pattern Analysis And Machine Intelligence, Vol. 24, No. 7, July 2002.
[10] Weifeng Su, Jiying Wang, Qiong Huang, Fred Lochovsky; Query Result Ranking over E-commerce Web Databases; CIKM'06,
November 6–11, 2006, Arlington, VA Virginia, USA.

Paper Type	:	Research Paper
Title	:	Exploration of Recent Advances in the Field of Brain Computer Interface
Country	:	India
Authors	:	M. Rajyalakshmi, T. Kameswara Rao, Dr. T. V. Prasad
	:	10.9790/0661-0821924

Abstract:A new approach for implementing number of expressions, emotions and, actions to operate objects through the thoughts of brain using a Non-Invasive Brain Computing Interface (BCI) technique has been proposed. In this paper a survey on brain and its operations are presented. The steps involved in the brain signal processing are discussed. The current systems are able to present few expressions and emotions on a single device. The proposed system provides the extended number of expressions on multiple numbers of objects.
Keywords: Brain Computer Interaction (BCI), Electroencephalogram (EEG), Expressions, Emotions.

[1] "Brain Facts, A Primer on the brain and nervous systems", http://www.sfn.org/skins/main/pdf/brainfacts/2008/brain_facts.pdf,
2008.
[2] "Brain-MindMachinery", available at www.worldscientific.com/ worldscibooks/10.1142/6704
[3] Lia Stannard, "Parts of the brain and their functions", Available: http://www.livestrong.com/article/77671-parts-brain-functions/, 2011.
[4] Jerry J.Shih;Dean. J. Krusienski: and Jonathan R, Wolpaw "Brain Computing Interfaces in Medicine", Mayo Clinical Proceedings,
Volume 87, pp 268-279, 2012.
[5] Erica Westly, "Fixing the Brain Computer Interface", IEEE Spectrum, July 2010.
[6] Theodore W. Berger, John K. Chapin, Greg Patrick A. Tresco, "Brain-Computer Interfaces-An International Assessment of
Research & Development Trends", Springer, 2008.
[7] Reza Fazel Rezai, "Recent advances in Brain Computer-Interface systems", InTech Publication, 2011.
[8] Niels Birbaumer, "Breaking the silence: Brain Computer Interfaces (BCI) for communication and motor control",
Psychophysiology, 43, 517–532, 2006.
[9] Leigh R. Hochberg, John P. Donoghue, "Sensors for Brain Computer-Interfaces", IEEE Engineering and Medicine, 2006.
[10] Jorge Baztarrica Ochoa, Gary Garcia Molina, Touradj Ebrahimi, "EEG signal classification for Brain Computer Interface
Applications", 2002.