Faculty Publications
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Publications by NITK Faculty
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Item Development of probabilistic simulation model for production optimization in open pit mines(Nova Science Publishers, Inc., 2011) Raj, M.G.; Vardhan, H.; Rao, Y.V.Large mechanized open pit operations can become more efficient and competitive without additional costs by improving the productivity of the existing machinery. This can be achieved by ensuring higher availability and utilization of the equipment The present paper deals with truck dispatch system using a variety of strategies to enhance the production capacity of a given set of equipment (shovels and trucks) by way of continuous dispatching of trucks. A discrete event probabilistic simulation program has been developed to demonstrate the production potential of an operating mine. It can accommodate any number of shovels and trucks of different capacities. The characteristic features of each truck and shovel can be individually specified to reflect the reality of actual working conditions. The model was tested on a hypothetical mine and a real case to verify the logic used in the program development. Subsequently, the model was implemented in two real mines to investigate the production potential. It was observed that substantial scope exists for productivity improvement when the mines were operating on a flexible mode. © 2012 by Nova Science Publishers, Inc. All rights reserved.Item Energy sector reforms in India - a review(2008) Mangalpady, M.; Raj, M.G.Indian economy has been growing at a rate of 6-8 % annually during the 10th plan period (2002-07), which requires growth of basic infrastructural facilities at a still higher rate. Power sector is one of the major components of infrastructure development, which requires a growth rate of 9-10 % during the 11th and 12th plan periods (2007-2016). This requires huge amount of investments and restructuring of power sector, for which Government cannot fund the entire amount independently. Hence, private participation is necessary either as an independent venture or through public-private partnership (PPP). Electricity Act 2003 is a step in the direction of reforms by creating an environment for private participation in the generation, transmission and distribution of power in the country. The main aim of this Act is to implement proper steps for efficient and optimum use of energy resources available in India and to supply quality power at good reliability and optimum cost to the Indian consumers. However, one of the major constraints faced by the power sector is the lack of adequate R&D support. This paper attempts to throw a light on present status of Indian power sector with respect to generation, transmission and distribution of electricity.Item Production optimisation using simulation models in mines: A critical review(Inderscience Publishers, 2009) Raj, M.G.; Vardhan, H.; Rao, Y.V.The mining industry is faced with the task of responding to increased demand for mineral resource products, decreasing ore grades, stringent quality requirements and strict environmental regulations in trying to meet the demands of the economy. This situation has necessitated the search for more scientific and technological innovations that enable profitable mining like simulation studies. In this paper, system simulation studies in underground and open-pit mines, shovel truck simulation have been discussed in detail. The study shows wide applicability of simulation studies in various operations in both underground and open-pit mines. Copyright © 2009, Inderscience Publishers.Item ZigBee based Real Time System for Environmental Parameters Monitoring in Model Mine: An Experimental Study(World Researchers Associations, 2025) Naik Anil, S.; Kumar, R.S.; Raj, M.G.The global mining industry, known for extracting valuable minerals like coal, iron ore, gold, silver, copper and zinc, primarily operates through underground mining. These underground mine environments are influenced by various environmental factors including toxic and flammable gases, increased carbon dioxide (CO2) levels and decreased oxygen (O2) concentrations. These factors significantly impact the productivity and safety of mine workers, making monitoring harmful gases crucial. Various methods exist to measure gas concentrations and respond appropriately when these levels exceed safe thresholds. However, each method has its own set of limitations. In underground mines, wireless monitoring systems are essential to monitor environmental parameters in real time. This study focuses on the assessment of ZigBee-based wireless techniques for their application in underground mines. The developed ZigBee wireless communication system was tested and validated at the surface level and in a model mine laboratory at the Mining Engineering Department of the National Institute of Technology Karnataka (NITK), Surathkal, India. This laboratory replicates an underground mine setting. The ZigBee-based system is designed to wirelessly monitor environmental parameters. Experiment results suggest that the ZigBee network is suitable for real-time monitoring of environmental conditions in underground mines. Further details regarding the functioning, effectiveness and potential applications of the ZigBee-based system in underground mining are discussed in the study. © 2025, World Researchers Associations. All rights reserved.Item An experimental investigation of the sound level produced by bulldozers with various maintenance schedules(Inderscience Publishers, 2008) Vardhan, H.; Raj, M.G.This study was made to understand and evaluate the effect of maintenance on noise production from bulldozers through experimental measurements of sound levels in a large open cast mine. Assessment of sound pressure levels at each periodic maintenance interval revealed that maximum sound level reduction was achieved at 1000 h maintenance schedule. For other periodic maintenance intervals, reduction in A-weighted sound pressure level was below 1.0 dB. The study revealed that primarily, the major noise-generating systems in Heavy Earth Moving Machinery (HEMM) are air, exhaust, cooling and fuel systems. However, maintenance of lubricant, transmission and hydraulic systems yielded no significant improvements in sound levels. Results also indicated sound level emissions from various systems to lie in different frequency ranges. © 2008, Inderscience Publishers.Item Artificial neural network modeling for predicting the screening efficiency of coal with varying moisture content in the vibrating screen(Routledge, 2021) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.In India, coal is one of the prime sources of energy used in the power generation and metallurgy sector. The processing of coal below 3 mm is not successfully carried out in India. The quality of coal below 3 mm can be improved by decreasing the coal’s particle size, which reduces the ash percentage of coal. Screening is one of the significant beneficiation techniques used to reduce the size fraction of coal. The difficult to process coal of size ?3 + 1 mm was selected in the present work. In this work, an attempt has been made to screen the coal of size ?2 + 1 mm from ?3 + 1 mm using a 2 mm screen mesh in the vibrating screen generated at different moisture content, angle, and frequency of the deck. The performance of the vibrating screen was evaluated using screening efficiency. Furthermore, prediction using a feed backward artificial neural network (ANN) model was developed on the experimental results for ten different neuron conditions. From the results, it was clear that the prediction results obtained from the ANN model were in good correlation with the experimental results. © 2021 Taylor & Francis Group, LLC.Item Evaluation of a new vibrating screen for dry screening fine coal with different moisture contents(Routledge, 2022) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.A new vibrating screen was developed with a circular mode of vibration for dry screening of moist coal of size fraction ?3 + 1 mm. Screen mesh of 2 mm aperture size will be used to separate the finer coal particles of size fraction ?2 + 1 mm. The new vibrating screen has the flexibility in changing the operational parameters such as the angle of the screen in upward or downward sloping direction and frequency of vibration of the screen deck. The circular mode of vibration provided to the screen deck will incorporate the inertial force on the particle in the screen deck, reducing screen clogging. The present study involves the analysis of the screening performance of the new vibrating screen with the coal feed of varying moisture content of 4%, 6% and 8%. The maximum screening efficiencies obtained for screening the coal feed with the moisture contents of 4%, 6% and 8% were 85.96%, 77.84%, and 68.27%, respectively. The higher screening performance of new vibrating screen was obtained due to good exposure time, particle mixing, particle segregation and particle stratification of coal on the screen deck. The results of the new vibrating screen will be a breakthrough in dry screening technology and accelerate the pilot-scale development. © 2019 Taylor & Francis Group, LLC.Item Experimentation and statistical prediction of screening performance of coal with different moisture content in the vibrating screen(Routledge, 2022) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.Screening of coal is one of the processes carried out to produce clean coal suitable for the blast furnace. In this work, the screening of moist coal was carried out for different angles of the screen and frequencies. A 2 mm screen perforation was used to separate undersize coal of size +1 mm-2 mm from the +1 mm-3 mm coal samples. For each experimental condition, the screening efficiency was calculated. Maximum screening efficiency of 85.96%, 75.64%, and 63.46% was obtained at 4%, 6%, and 8% moisture content, respectively. As the moisture content of coal increases, the efficiency minimizes due to high screen clogging. After determining the screening efficiency, prediction was carried out using regression modeling. In this work, linear and second-order polynomial regression modeling was utilized to develop a prediction model for the experimental values. From the results, it was clear that the polynomial regression model has high regression coefficient (R2) percentage and low P-value in comparison with the linear regression model. After prediction, validation was carried out on the best fit model. The value of Variance Account For (VAF), Root Mean Square Error (RMSE), and Mean Absolute Percentage Error (MAPE) was in the acceptable range, which shows that the developed model was most effective. © 2020 Taylor & Francis Group, LLC.Item ANN modeling and residual analysis on screening efficiency of coal in vibrating screen(Taylor and Francis Ltd., 2022) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.In this paper, coal screening in vibrating screen was carried out with the size ranges of ?6 mm + 4 mm, ?4 mm + 2 mm, and ?2 mm + 0.5 mm. The vibrating screen was newly designed with flexibility in angle and frequency. The vibrating screen experimentation was carried out by varying screen mesh, angle, and screen frequency. During the screening, the angle was kept constant, and frequency was varied to obtain each size range’s screening efficiency. The experimental results of screening efficiency were evaluated for each size fraction range of coal. The maximum efficiency for screening coal with ?6 mm+4 mm, ?4 mm+2 mm, and ?2 mm+0.5 mm size range obtained was 87.60%, 80.93%, and 62.96%, respectively. Further, the prediction model was developed for each size range using a feed-backward artificial neural network (ANN) to consider the back-propagation error technique. For each screening condition, 10 ANN models were developed with the variation in 1–10 different neurons. ANN has provided mathematical models with a 99.9% regression coefficient for predicting each size range’s screening efficiency. Furthermore, the residuals of each optimal ANN model were analyzed using a normal probability plot and histogram. The ANN model’s accuracy was obtained from the residual analysis by evaluating four different model conditions, i.e., independence, homoscedasticity, normality, and mean error. © 2021 Taylor & Francis Group, LLC.Item Regression modeling and residual analysis of screening coal in screening machine(Taylor and Francis Ltd., 2022) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.Coal is one of the chief energy sources having significant applications in the iron and steel industry. This research investigates the screening efficiency of coal of different size range. The experiments on the screening of coal with different size range in the screening machine were carried out using different mesh sizes. The screening efficiency for different screen angles and frequency of vibration was carried out. After experimentation, regression modeling was carried out for each screening condition. The maximum efficiency of screening coal with size range +4 mm-6 mm, +2 mm-4 mm, and +0.5 mm-2 mm obtained was 87.60%, 80.93%, and 62.96%, respectively. The experimental results show that the screening efficiency decreases with the decrease in size range for screening from +4 mm-6 mm to +0.5 mm-2 mm. The reduction in screening efficiency was due to the clogging of coal to the screen mesh. Linear and quadratic modeling were performed to estimate the efficiency of all the experimental results. After prediction, the validation using residual analysis was carried out, and the results illustrate that the quadratic prediction modeling was accurate. © 2021 Taylor & Francis Group, LLC.