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Soundar K.R.,PSR Engineering College | Murugesan K.,Bharathiyar Institute of Engineering for Women
International Journal of Pattern Recognition and Artificial Intelligence | Year: 2011

Computer face recognition promises to be a powerful tool and is becoming important in our security-heightened world. Several research works on face recognition based on appearance, features like intensity, color, textures or shape have been done over the last decade. In those works, mostly the classification is achieved by finding the minimum distance or maximum variance among the training and testing feature set. This leads to the wrong classification when presenting the untrained image or unknown image, since the classification process locates at least one winning cluster having minimum distance or maximum variance among the existing clusters. But for the security related applications, these new facial image should be reported and necessary action has to be taken accordingly. In this paper, we propose the following two techniques for this purpose: (i) Use a threshold value calculated by finding the average of the minimum matching distances of the wrong classifications encountered during the training phase. (ii) Use the fact that the wrong classification increases the ratio of within-class distance and between-class distance. Experiments have been conducted using the ORL facial database and a fair comparison is made with the conventional feature spaces to show the efficiency of these techniques. © 2011 World Scientific Publishing Company.


Ruba Soundar K.,PSR Engineering College | Murugesan K.,Bharathiyar Institute of Engineering for Women
IET Computer Vision | Year: 2010

Face recognition can significantly impact authentication, monitoring and indexing applications. Much research on face recognition using global and local information has been done earlier. By using global feature preservation techniques like principal component analysis (PCA) and linear discriminant analysis (LDA), the authors can effectively preserve only the Euclidean structure of face space that suffers lack of local features, but which may play a major role in some applications. On the other hand, the local feature preservation technique namely locality preserving projections (LPP) preserves local information and obtains a face subspace that best detects the essential face manifold structure; however, it also suffers loss in global features which may also be important in some of the applications. A new combined approach for recognising faces that integrates the advantages of the global feature extraction technique LDA and the local feature extraction technique LPP has been introduced here. Xiaofei He et al. in their work used PCA to extract similarity features from a given set of images followed by LPP. But in the proposed method, the authors use LDA (instead of PCA) to extract discriminating features that yields improved facial image recognition results. This has been verified by making a fair comparison with the existing methods. © 2010 The Institution of Engineering and Technology.


Saravanan P.,Jay Shriram Group of Institutions | Balakrishnan P.A.,Bharathiyar Institute of Engineering for Women
Research Journal of Applied Sciences, Engineering and Technology | Year: 2014

This research study mainly focuses on using an efficient control strategy for extracting reference currents of shunt active filters under non linear load conditions. In recent decades, the utilization of highly automatic electric equipments has resulted in enormous economic loss. Thus, the power suppliers as well as the power consumers are very much concerned about the power quality issues and compensation approaches. In order to deal with this issue, Active Power Filter (APF) has been considered as an attractive solution due to its significant harmonic compensation. But, the performance of APF is not consistent and is varies based on the output of the controller techniques. An efficient (iq - iq) control strategy is used in this approach for attaining utmost profit from grid-interfacing inverters installed in transmission systems. The voltages are controlled through the PI controller which is further tuned by an optimization approach. Bacterial Forge Optimization (BFO) is used in this approach for tuning the PI controller for the optimal value. The inverter used in this approach can be considered as a Shunt Active Power Filter (SAPF) to compensate non linear load current harmonics. In order to improve the overall performance of the system, Space Vector Pulse Width Modulation (SVPWM) is used in this proposed approach which regulates power frequency and produces good circularity through DC-AC part. SVPWM also eliminates the 3rd order harmonics and minimizes the 5th order harmonics effectively. The integration of (iq - iq) control strategy and SVPWM has been proposed in this research study. Simulation results are carried out in MATLAB/Simulink and the performance of the proposed approach is compared with other control strategies. This research studies shows unique approach for attaining maximum benefits from RES with suppression of current harmonics. © Maxwell Scientific Organization, 2014.


Saravanan P.,Jay Shriram Group of Institutions | Balakrishnan P.A.,Bharathiyar Institute of Engineering for Women
WSEAS Transactions on Power Systems | Year: 2014

In recent decades, the utilization of highly automatic electric equipments has resulted in enormous economic loss. Thus, the power suppliers as well as the power consumers are very much concerned about the power quality issues and compensation approaches. In order to deal with this issue, Active Power Filter (APF) has been considered as an attractive solution due to its significant harmonic compensation. But, the performance of APF is not consistent and is varies based on the output of the controller techniques. This research work mainly focuses on using an efficient control strategy for extracting reference currents of shunt active filters under non linear load conditions. An efficient (id - iq) control strategy is used in this approach for attaining utmost profit from grid-interfacing inverters installed in transmission systems. The voltages are controlled through the PI controller which is further tuned by an optimization approach. Bacterial Forge Optimization (BFO) is used in this approach for tuning the PI controller for the optimal value. The inverter used in this approach can be considered as a Shunt Active Power Filter (SAPF) to compensate non linear load current harmonics. In order to improve the overall performance of the system, Space Vector Pulse Width Modulation (SVPWM) is used in this proposed approach which regulates power frequency and produces good circularity through DC-AC part. SVPWM also eliminates the 3rd order harmonics and minimizes the 5th order harmonics effectively. The integration of (id - iq) control strategy and SVPWM has been proposed in this research work. Simulation results are carried out in MATLAB/Simulink and the performance of the proposed approach is compared with other control strategies. This research works shows unique approach for attaining maximum benefits from RES with suppression of current harmonics.


Balakrishnan P.A.,Bharathiyar Institute of Engineering for Women
WSEAS Transactions on Power Systems | Year: 2014

With rapid strides in the realm of power restructuring, the Unit commitment problem (UCP) has transformed itself into a dysfunctional amalgam of several variables relating to power system operation; commercial ones of the system operators and stochastic parameters corresponding to non-deterministic behavior of power equipment and accessories. The older set of UCP formulations has undergone sea changes in scope and enormity. Present ones have expanded to include indeterminate real life situations that require several probability measures. Corresponding solution techniques that address these amplified functions also need to be fitter, robust and versatile to generate acceptable and realistic optimal solutions. While there are classes of solutions galore, the state-space method is amenable to the inclusion of stochastic variables for generating effective UCP solutions. This paper attempts to graft random processes into the state space analysis of a generating block using a suitable selective state merger method employing appropriate transition rates. This helps to arrive at a reliability index that can vet a good UCP solution.

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