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Jayaswal P.,Madhav Institute of Technology and Science | Verma S.N.,Rajiv Gandhi Technical University | Wadhwani A.K.,Madhav Institute of Technology and Science
JVC/Journal of Vibration and Control | Year: 2011

The objective of this work is to develop techniques to automate the condition-based maintenance procedure. It is observed that vibration signals are capable of alarming the malfunctions in machineries. In order to overcome the shortcomings in the traditional vibration analysis using time-domain and frequency-domain features, two new approaches based on wavelet transform, artificial neural network and fuzzy rules are proposed for detecting and localizing defects in rolling element bearings. The two expert systems are developed and tested with the use of vibration signals collected from the bearing housing of an experimental setup. Experiment results show that the proposed approaches are sensitive and reliable in detecting defects on the outer race, inner race and rolling elements of bearings. The proposed approaches may be used for other fault diagnoses such as gear faults, coupling faults, belts in industries. It is also expected from the obtained results that the generalized defect detection will be easier in future by using the proposed approaches via other parameters such as noise, temperature, lubricant analysis in addition to used vibration signals. © The Author(s) 2010. Source

Arya L.D.,Shri Gs Institute Of Technology And Science | Choube S.C.,Rajiv Gandhi Technical University
International Journal of Electrical Power and Energy Systems | Year: 2012

This paper describes a technique for selection of buses in a sub transmission system for location of distributed generation (DG) and determination of their optimum capacities by minimizing transmission losses. The buses have been selected based on incremental voltage (dV/dP) sensitivities. Line flow constraints have been accounted. Type-3 DG i.e. wind turbine along with induction generator has been considered for the study. Differential evolution (DE) has been used to evaluate the optimum DG capacity and results have been compared with those obtained using bare bones particle swarm optimization (BBPSO) and multi-membered non-recombinative (μ + λ) evolution strategy (MMNRES). The developed algorithms have been implemented on standard 6-bus and 30-bus test systems. © 2012 Elsevier Ltd. All rights reserved. Source

Sharma M.,Rajiv Gandhi Technical University | Verma A.,Institute of Engineering and Technology
International Journal of Control, Automation and Systems | Year: 2013

This Paper investigates the mean to design the reduced order observer and observer based controllers for a class of uncertain nonlinear system using reinforcement learning. A new design approach of wavelet based adaptive reduced order observer is proposed. The proposed wavelet adaptive reduced order observer performs the task of identification of unknown system dynamics in addition to the reconstruction of states of the system. Reinforcement learning is used via two wavelet neural networks (WNN), critic WNN and action WNN, which are combined to form an adaptive WNN controller. The "strategic" utility function is approximated by the critic WNN and is minimized by the action WNN. Owing to their superior learning capabilities, wavelet networks are employed in this work for the purpose of identification of unknown system dynamics. Using the feedback control, based on reconstructed states, the behavior of closed loop system is investigated. By Lyapunov approach, the uniformly ultimate boundedness of the closed-loop tracking error is verified. A numerical example is provided to verify the effectiveness of theoretical development. © 2013 Institute of Control, Robotics and Systems and The Korean Institute of Electrical Engineers and Springer-Verlag Berlin Heidelberg. Source

Shukla R.K.,Rajiv Gandhi Technical University
Journal of Applied Polymer Science | Year: 2012

This study describes the application of response surface methodology in the optimization of guar gum microspheres for colon-specific delivery of metronidazole. The effect of varying the relative percent of the four factors used, that is guar gum, glutaraldehyde, swelling time, and stirring speed, has been systematically investigated for identifying their best values to optimize the drug release and encapsulation efficiency as well as to highlight possible interactions among the components. Different batches were prepared according to 24 factorial designs and randomly evaluated for drug release and drug encapsulation efficiency. Analysis of response surface plots allowed identification of the best combination of four levels to minimize drug release in upper part of gastrointestinal tract and maximize the encapsulation efficiency. The scanning electron microscopy was used to characterize the surface of these microspheres. Drug polymer interactions were assessed by differential scanning calorimetry and XRD. The good correspondence between calculated and experimental values indicated in the validity of the generated statistical model. Only a small fraction of drug was released at acidic pH; however, the release of drug was found to be higher in the presence of rat cecal contents, indicating the susceptibility of crosslinked guar gum matrix to colonic enzymes released from rat cecal contents. Metronidazole release kinetics corresponds best to zero-order model and drug release mechanism was diffusion and swelling controlled. The significance of differences was evaluated by analysis of variance (ANOVA). Differences were considered statistically significant at P < 0.05. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 Copyright © 2012 Wiley Periodicals, Inc. Source

Thapar V.,Rajiv Gandhi Technical University
Solar Energy | Year: 2015

Objective of this study is to analyse the impact of main factors, viz., load being supplied, wind speed, global irradiance, ambient temperature and battery bank capacity (BBC), on the performance of Hybrid Energy System (HES). Levelised Cost of Energy (LCE) and Loss of Power Supply Probability (LPSP) have been considered as performance indicators. Energy balance approach is used for calculating BBC and corresponding LCE at desired LPSP for the selected system configuration and inputs.It is concluded that for a given load, with increase in BBC, the LCE increases linearly, whereas LPSP decreases exponentially. With increasing load, the BBC required for supplying power at a given LPSP, and corresponding LCE initially increase gradually and then sharply and linearly. With increase in wind speed, BBC and corresponding LCE initially decrease sharply and then gradually; this variation is more prominent for higher loads. The BBC and corresponding LCE decrease with increase in global irradiance, the decrease is gradual for low loads; whereas, for large loads the decrease is initially sharp and then gradual. The BBC required for supplying power to a given load at a given LPSP, and corresponding LCE, increase almost linearly with increase in annual average of hourly ambient temperature. © 2015 Elsevier Ltd. Source

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