2. Conference Papers
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Item Modelling and simulation of a wind/diesel hybrid power system(2006) Kini, A.S.; Yaragatti, Udaykumar R.In remote and isolated areas far from the grid, it may not be an economically viable option to supply electric power from the grid. This is due to the high cost of transmission lines and higher transmission losses that accompany distribution of centrally generated power to remote areas. In such cases hybrid systems such as wind/diesel generators are found to be the most reliable, preferred and attractive alternative source of power supply. This paper presents the modelling and performance analysis of wind/diesel hybrid generating system. To regulate the frequency and voltage output of the wind generator, an AC-DC-AC scheme using SPWM technique is employed. To evaluate the performance and stability of the hybrid system, it is simulated for different disturbances involving variation in wind speed and load conditions using EMTDC/PSCAD software.Item Modelling and performance analysis of a wind/diesel hybrid power system(2006) Kini, A.S.; Udaykumar, R.Y.Domestic consumers in the remote places who are not connected by the main electrical grid network, hybrid systems such as wind/diesel generators have been considered as the most reliable, preferred and attractive alternative source of power supply. This paper presents the modeling and performance analysis of wind/diesel hybrid generating system. To regulate the frequency and voltage output of the wind generator, an AC-DC-AC scheme using SPWM technique is employed. The system is simulated for different wind speed and load conditions using EMTDC/PSCAD software. � 2006 IEEE.Item Modeling of phenol degradation in spouted bed contactor using artificial neural network (ANN)(2008) Dabhade, M.A.; Saidutta, M.B.; Murthy, D.V.R.Presence of phenol and phenolic compounds in various wastewaters and its harmful effects has led to the use of different treatment methods. Work on biological methods shows the use of different microorganisms and different bioreactors so as to improve the removal efficiency economically. The present work deals with the use of N. hydrocarbonoxydans (NCIM 2386), an actinomycetes, for the degradation of phenol. N. hydrocarbonoxydans was immobilized on GAC and used in a spouted bed contactor for effective contact of microorganisms and the substrate. The contactor performance was studied by varying flow rates, influent concentrations and the solids loading in the contactor. The effect of these variables on phenol degradation was investigated and modeling study was carried out using the artificial neural network (ANN). A feed forward neural network with back propagation was used for the model development. The experiments were planned as per the face centered cube design (FCCD) and used for training of the model, whereas data from four other experimental runs were used for testing and validation of the model. The network was optimized for the number of neurons based on the mean square error. The ANN model with three layers with three input neurons, eight neurons in hidden layers and one output neuron was found to predict effectively the effluent concentration for the given operating conditions in the spouted bed contactor. The mean square error was found to be 9.318e-12 for this ANN model. Also the experimental data was used to develop second order nonlinear empirical model obtained using multiple regression (MR) and the results compared with ANN using correlation coefficient (R2), average absolute error (AAE) and root mean square error (RMSE). Results show that R2, AAE and RMSE values of MR model were 0.9363, 2.085 % and 2.338 % respectively, while in case of ANN model these values were 0.9995, 0.59 % and 1.263 % respectively. This shows that ANN model prediction is better than multiple regression model prediction. Copyright � 2008 The Berkeley Electronic Press. All rights reserved.Item Reliable transmission and storage of medical images with patient information using error control codes(2004) Nayak, J.; Bhat, P.S.; Kumar, M.S.; Rajendra, Acharya, U.A new method for compact storage and transmission of medical Images with concealed patient Information in noisy environment if evinced. Digital Watermarking is the technique adapted here for interleaving patient Information with medical images. The patient information, which comprises of text data and signal graph, is encrypted to prevent unauthorized access of data. The latest encryption algorithm (Rijndael) is used for encrypting the text information. Signal graphs (ECG, EEG EMG etc.) are compressed using DPCM technique. To enhance the robustness of the embedded information, the patient Information Is coded by Error Correcting Codes (ECC) Reed Solomon (RS) codes. The noisy scenario Is simulated by adding salt and pepper (S&P) noise to the embedded Image. For different Signal to Noise Ratio (SNR) of the image, Bit Error Rate (BER) and Number of Character Altered (NOCA) for text data and percentage distortion (PDIST) for the signal graph is evaluated. It Is elicited that coded systems can perform better than the uncoded systems. � 2004 IEEE.Item Reliable and robust transmission and storage of medical images with patient information(2004) Nayak, J.; Subbanna, Bhat, P.; Kumar, M.S.; Rajendra, Acharya, U.A new method for compact storage and transmission of medical images with concealed patient information in noisy environment is evinced. Digital Watermarking is the technique adapted here for interleaving patient information with medical images. The patient information, which comprises of text data and signal graph, is encrypted to prevent unauthorized access of data. The latest encryption algorithm (Rijndael) is used for encrypting the text information. Signal graphs (ECG, EEG EMG etc.) are compressed using DPCM technique. To enhance the robustness of the embedded information, the patient information is coded by Error Correcting Codes (ECC) such as (7,4) Hamming, Bose-Chaudhuri-Hocquenghem (BCH) and Reed Solomon (RS) codes. The noisy scenario is simulated by adding salt and pepper (S&P) noise to the embedded image. For different Signal to Noise Ratio (SNR) of the image, Bit Error Rate (BER) and Number of Character Altered (NOCA) for text data and percentage distortion (PDIST) for the signal graph are evaluated. The performance comparison based on the above parameters is conducted for three types of ECC. It is elicited that coded systems can perform better than the uncoded systems. � 2004 IEEE.Item Recent developments in control schemes of BLDC motors(2006) Vinatha, U.; Pola, S.; KPVittalThis paper presents a technical review of published literature addressing control schemes for BLDC motors. The control methods reviewed include sensor less control, PWM techniques used, various methods for rotor position detection and initial rotor position detection methods.Item Real time microseismic monitoring to study geomechanics of underground structures(2008) Sivakumar, C.; Srinivasan, C.; Willy, Y.A.; Murthy, Ch.S.N.The study of Geomechanics of underground structures in real time requires capture of fracture information well in advance from structure failure to initiate remedial measures during development and after completion of structure. The advanced high dynamic range microseismic instrumentation with latest Computer methods/algorithms helped to investigate strata behaviour in real time. One such investigation was carried out at the Rajendra longwall underground coal mine, Madya Pradesh state India and addressed major concerns of the mines like roof falls, stability of workings, goaf caving process etc,. The results of this study demonstrated that microseismic monitoring is very useful in understanding the geomechanics of underground structures. Among the several seismic source parameters obtained, the reliable precursor found was the microseismic Event Release Rate (ERR) of micro fractures before failure, which is the most significant instability indicator of underground structure. Results from this work can be useful to other underground structures such as tunnels and LPG storage caverns.Item Query language interface for ubiquitous objects(2008) Kulkarni, U.P.; Vadavi, J.V.; Yadwad, R.N.; Ahmed, T.; Chandra, Sekaran, K.; Yardi, A.R.The vision of ubiquitous computing (UC) has been described in terms of the disappearing computers. To achieve this invisibility, the interactions between various objects of daily life should be as free as possible from explicit human administration. UC will enable the new breed of applications and systems resulting in to a smart world (SW) in which computational intelligence is distributed throughout the physical environment to provide services to people. To embed such autonomic behavior in every day objects around us, it is necessary to build knowledge repository, which helps objects in smart world to monitor, plan, analyze and execute autonomously like human being. In this paper author proposes query language interface for such knowledge representation of ubiquitous objects, which enables object aware capability and hence the object intelligence. � 2007 IEEE.Item Radiation performance of an elliptical patch antenna with a circular for modern communication systems(2008) Bhardwaj, D.; Bhardwaj, V.; Bhatnagar, K.D.; Sancheti, S.The paper presents the radiation performance of an elliptical (a=15mm, b=10.5mm) patch antenna having circular slot (R=4.8mm) designed on glass epoxy FR4 substrate and its performance is compared with a simple elliptical patch antenna without slot. The simulation results for this antenna are obtained with available IE3D simulation software by varying semi major axis (a) and semi minor axis (b). The elliptical patch antenna with circular slot of specific radius not only resonates at two different frequencies but also presents a relatively wide bandwidth, higher directivity and enhancement of gain. By designing antenna on low permittivity substrate, a much higher bandwidth may be achieved. �2008 IEEE.Item Quality driven web service selection and ranking(2008) D'Mello, D.A.; Ananthanarayana, V.S.The increasing number of Web service providers with numerous functionally similar or same Web services produced a new problem of choosing a suitable Web service for the requester based on his expectations. The Quality of Service (QoS) can be used to select and rank functionally similar Web services. In this paper we define four Web service provider qualities to distinguish functionally similar and qualitatively competitive Web services. The main objective of this paper is to explore the mechanism which breaks the tie that may arise among functionally similar and qualitatively equivalent (competitive) Web services during Web service selection and ranking. � 2008 IEEE.