Journal Articles
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Item Understanding the role of modeling and simulation in pyrolysis of biomass and waste plastics: A review(Elsevier Ltd, 2022) Ramesh, R.; Suriapparao, D.V.; Sankar Rao, C.S.; Kumar, T.H.The valorization of resources from biomass and plastic waste using thermochemical platforms is an innovative approach. Pyrolysis is thermochemical technology that is very effective in the production of fuels and chemical intermediates. It's conducted by conventional heating, solar heating, and microwave-controlled heating. Compared to conventional pyrolysis, microwave-assisted pyrolysis is more advantageous. The temperature distribution, mass transfer, and heat transfer rates depend on the operation mode through process parameters. The optimization of the pyrolysis process is crucial for scale-up. Computer-assisted modeling and simulation techniques help to develop suitable configurations and experimental methods for better efficiencies. Modeling allows the identification of optimum operating parameters and understanding of transportation mechanisms involved in pyrolysis. Modeling, simulation, and optimization are ideally suited to understanding and analyzing the complex stages of pyrolysis. This review provides insight into existing heat, mass, and momentum transfer models for pyrolysis. The effects of transport properties on pyrolysis are dealt with. © 2022 Elsevier LtdItem Optimization of simply-supported symmetrical trough type folded plate roofs using improved move-limit method of sequential linear programming and sequential unconstrained minimization technique is discussed. Improved move-limit method of sequential linear programming has been found to be suitable for optimization of trough type folded plate roofs and using the same, the effect of cost ratio on optimum design variables and the effect of the number of trough units for a given span on optimum design have been studied and discussed. Optimum dimensions have been prepared for various spans normally encountered. © 1995.(Optimum design of trough type folded plate roofs) Lakshmy, T.K.; Bhavikatti, S.S.1995Item This paper deals with an experimental investigation on the process of atmospheric plasma spraying of high performance ceramics such as Al2O3, Al2O3-TiO2, and PSZ on a steel substrate. The ceramic coatings were deposited under different spray conditions and optimal spray parameters were evaluated based on the quality of the coating judged in terms of bond strength and porosity. An expert system, using the above experimental data,developed in Borland C has been demonstrated.(Elsevier BV, Expert system for process optimization of atmospheric plasma spraying of high performance ceramics) Gowri, S.; Uma Shankar, G.; Narayanasamy, K.; Krishnamurthy, R.1997Item Unintentionally doped homoepitaxial InSb films have been grown by liquid phase epitaxy employing ramp cooling and step cooling growth modes. The effect of growth temperature, degree of supercooling and growth duration on the surface morphology and crystallinity were investigated. The major surface features of the grown film like terracing, inclusions, meniscus lines, etc are presented step-by-step and a variety of methods devised to overcome such undesirable features are described in sufficient detail. The optimization of growth parameters have led to the growth of smooth and continuous films. From the detailed morphological, X-ray diffraction, scanning electron microscopic and Raman studies, a correlation between the surface morphology and crystallinity has been established.(Indian Academy of Sciences, Influence of growth parameters on the surface morphology and crystallinity of InSb epilayers grown by liquid phase epitaxy) Udayashankar, N.K.; Bhat, H.L.2003Item A new approach for channel blind identification based on second order cyclostationary statistics and the group delay has been proposed. In this, two methods are proposed. In both the methods, the correction is applied to the basic phase estimate for both the poles and zeros, in the group delay domain. The basic phase estimate is derived from the spectral correlation density (SCD) of the system output. In the first method, the phase correction is based on magnitude group delay. In the second method, not only the phase correction but also an improved system magnitude estimate of better variance and frequency resolution is derived based on modified magnitude group delay. The results indicate a significant improvement in performance for both the methods. For the first method in the absence of noise, the percentage normalized mean square error is reduced by about 85% over that of the existing non-parametric method. The second method in the presence of noise (SNR=5 dB), provides a reduction of 74% over the existing non-parametric method and 57% over the existing combined parametric and non-parametric methods. © 2005 Elsevier B.V. All rights reserved.(Channel blind identification based on cyclostationarity and group delay) Narasimhan, S.V.; Hazarathaiah, M.; Giridhar, P.V.S.2005Item Design of haul road lighting system. Part II: Design based on optimal cost considerations(2006) Karmakar, N.C.; Mangalpady, M.; Rao, Y.V.; Yaragatti, U.R.The proper selection of lighting installations is very important for the provision of cost-effective lighting systems without compromising light quality. In this study a computer program was developed to evolve a cost-effective lighting system for haul roads in surface mines. This program is beneficial in assessing the viability of various lighting installations in order to achieve cost-effective solutions. Using the program, illumination design was studied for an 800 m long stretch of haul road. Nine different types of light sources were considered at mounting heights of 12 m and 16 m. The study shows that at a 12 m mounting height, 100 W high-pressure sodium vapour (HPSV) lamps offer the most cost-effective design, followed by 250 W HPSV lamps. In the case of 16 m pole heights the annual lighting cost is minimum for 150 W HPSV lamps, followed by 250 W HPSV lamps. This work also shows that optimum design based on energy consumption need not be the same as design based on optimum cost considerations as cost parameters may vary widely with location.Item Design of haul road lighting system. Part I: Design based on optimal energy considerations(2006) Karmakar, N.C.; Mangalpady, M.; Rao, Y.V.; Yaragatti, U.R.Electrical energy consumption is a major cost component of haul road lighting. Haul road lighting depends on many parameters such as type and wattage of sources, mounting height and tilt angle of light fixtures. In this study a computer model has been developed for optimum energy consumption of any haul road lighting system. Using the program, illumination design was studied for a stretch of 800m long haul road. Nine different types of light sources were considered for mounting heights of 12 and 16m. High-pressure sodium vapour (HPSV) lamps of 100W proved to be energy efficient at a 12m height whereas at 16m height, energy consumption was minimum for 150 W HPSV lamps. Thus the developed computer program proved to be successful in evaluating the performance of lighting designs from the point of view of energy consumption.Item Optimization of WDM lightwave systems (BAC) design using error control coding(Academic Press Inc., 2007) Mruthyunjaya, H.S.; Umesh, G.; Kumar, M.In a binary asymmetric channel (BAC) it may be necessary to correct only those errors which result from incorrect transmission of one of the two code elements. In optical fiber multichannel systems, the optical amplifiers are critical components and amplified spontaneous emission noise in the optical amplifiers is the major source of noise in it. The property of erbium doped fiber amplifier is nearly ideal for application in lightwave long haul transmission. We investigate performance of error correcting codes in such systems in presence of stimulated Raman scattering and amplified spontaneous emission noise with asymmetric channel statistics. Performance of some best known concatenated coding schemes is reported. © 2006 Elsevier Inc. All rights reserved.