Browsing by Author "Raj, M.G."

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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.
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.
Application of fractional factorial design for evaluating the separation performance of the screening machine
(Taylor and Francis Ltd., 2022) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.
Implementing the planned execution of experiments will optimize the resources and time of a newly developed process or equipment. In the present work, the screening machine is newly developed equipment designed for the separation of coal. The present work was carried out to evaluate the performance of separation efficiency of the screening machine using generalized and forward selection fractional factorial experimental design. Further, the present work will also determine the significance of each operational variable, such as moisture content, angle, and frequency, for increasing separation efficiency. A cube plot was developed from the experimental design, which shows the highest and lowest condition of separation efficiency for each level of the operational variables. Further, a Pareto chart was developed to evaluate the significant operational variable for the screening machine. The results of the generalized method and forward selection method of fractional design show that the moisture content was the most significant operational variable, followed by angle and frequency. The results also show that the screen blinding of a screening machine plays an important role in reducing the separation efficiency of a screening machine. © 2021 Taylor & Francis Group, LLC.
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.
Comparison of the prediction performance of separating coal in separation equipment using machine learning based cubic regression modelling and cascade neural network modelling
(Taylor and Francis Ltd., 2023) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.
The availability of low-grade coal with a high amount of ash has urged the improvisation of separation equipment with minimal or no water utilization. The present work addresses the study on the separation equipment performance with different moisture coal. The experimental results were obtained in terms of separation efficiency. After obtaining the experimental results, the mathematical modeling results were obtained using different techniques. The cubic regression and cascade neural network models were considered to study the mathematical correlation with experimental results. The R-squared value of each mathematical modeling technique was correlated with the model fitting to check the model’s validity. The results clearly showed that the cubic model fitting for the experimental condition had provided an excellent R-squared value varying from 92% to 99%. The cascade model fitting for the experimental condition has provided a higher R-squared value, i.e., more than 99%. Results show that for all experimental conditions, the cascade model fitting of the neural network technique provides the significant mathematical modeling technique suitable for predicting the separation equipment’s performance compared to the cubic model of the regression technique. © 2022 Taylor & Francis Group, LLC.
Comparison of the predictive model performance of Taguchi’s L27 and Box Behnken design optimization method for separating coal in vibrating screen
(Taylor and Francis Ltd., 2023) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.
The present research work evaluates the influential process parameters such as moisture content, angle, and frequency for separating coal in the vibrating screen. The design of the experiment for three factors with three levels was obtained using Taguchi’s and Response surface methodology’s (RSM) method. Taguchi’s L27 and RSM Box–Behnken design (BBD) method was used to conduct the separation experiment on a vibrating screen. The main effect plot of Taguchi’s L27 and BBD method was used to evaluate the optimized condition for obtaining the highest separation efficiency of the vibrating screen. The optimized condition obtained was lower moisture content (4%), lower angle (1 degree in upward slope), and medium frequency (9 Hz). The interaction plot of Taguchi’s L27 and BBD method was used to evaluate the interaction between the process parameters. From the interaction plot and ANOVA results, it was clear that the moisture content is the most significant parameter compared with the angle and frequency parameter for separating coal in a vibrating screen. From the prediction results, it was also clear the regression coefficient of Taguchi’s L27 was higher when compared with the RSM BBD method. This shows that Taguchi’s L27 is the most suitable optimization method compared with RSM. © 2022 Taylor & Francis Group, LLC.
Development of a Novel Real-Time Environmental Parameters Monitoring System Based on the Internet of Things with LoRa Modules in Underground Mines
(Springer, 2023) Kumar Reddy, S.K.; Naik, A.S.; Raj, M.G.
The mining industry relies on extracting valuable minerals through underground mining. Many industries have implemented automation to enhance workplace safety, optimize operations, improve responses to events, and achieve cost-effectiveness. A real-time communication and monitoring system is indispensable in underground mines to prevent significant hazards and improve safety in underground mines. However, the environmental conditions of underground mines are affected by toxic, flammable, combustible gases and dust. The harmful gases are a significant concern as they can cause gas explosions. Internet of Things (IoT) enabled real-time communication system with Long Range (LoRa) transceiver module is designed and developed to measure the underground mine environmental parameters, temperature, and humidity. The LoRa-based proof of concept (POC) system is tested and evaluated at the surface level and in two underground mines. The LoRa module radio waves range test is carried out to measure the received signal strength indicator (RSSI) value at the surface level. In addition, the developed system is tested and evaluated at different positions of underground mines to measure environmental parameters in straight and curved tunnels. The experimental results represent successful IoT with LoRa-based wireless communication between underground mine tunnels to the surface, wireless transmission of parameters at the straight tunnels, and curved tunnels of underground mines. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.
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.
Effective Maintenance Planning for Improving the Reliability of Underground Mining Equipment—A Case Study
(Acadlore Publishing Services Limited, 2025) Balaraju, B.; Raj, M.G.; Tripathi, A.K.
The Load Haul Dumper (LHD) is essential machinery utilized for moving ore in the underground mining industry, in order to fulfil production targets. In this connection, the efficiency of the equipment should be maintained at an ideal standard, to be accomplished by reducing unexpected failure of components or subsystems in this intricate system. Downtime analysis helped identify faulty components and subsystems, which require the development of complementary maintenance plans to facilitate the replacement or fixing of parts. Proper practices of maintenance management improve the performance of the equipment. In this research, the efficiency of the LHD machine was assessed through reliability methods. Initially, the assumption of independent and identical distribution (IID) for the data sets was validated using trend and serial correlation analyses. The statistical tests indicated that the data sets adhered to the IID assumption. Therefore, a renewal process method was utilized for additional examination. The Kolmogorov-Smirnov (K-S) test was utilized to identify the most suitable distribution for the data sets. The theoretical probability distributions were estimated parametrically using the Maximum Likelihood Estimate (MLE) approach. The dependability of each separate subsystem was determined using the optimal fit distribution. Based on the reliability outcomes, preventive maintenance (PM) time plans were created to reach the targeted 90% reliability. Different maintenance strategies, in addition, were suggested to the maintenance team to extend the lifespan of the machine. © 2025 by the author(s). Licensee Acadlore Publishing Services Limited, Hong Kong.
Energy sector reforms in India - a review
(2008) Aruna, 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.
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.
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.
Experimental analysis of vibratory screener efficiency based on density variation for screening coal and iron ore
(Taylor and Francis Ltd., 2024) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Hanumanthappa, H.; Reddy Byrareddy, R.; Sah, R.
In the coal and mineral beneficiation industries, screening is one of the crucial physical separation methods carried out to separate the undersized fine particles from the oversize coarse particles. The vibratory screener is a relatively advanced screening technology applied for coal and iron ore beneficiation. This paper deals with the experimental investigation for assessing the efficiency of screening coal and iron ore in the vibratory screener. Furthermore, a comparative study between the test performance of screening coal and iron ore was carried out depending on moisture and density variation. Test results show that the vibratory screener can provide a high recovery of fines and increased efficiency for screening iron ore than coal material. The maximum efficiency of iron ore was attained at a higher angular position, such as 3 and 5 degrees in an upward slope, whereas the maximum efficiency of coal was attained at 1 degree in an upward slope. © 2023 Taylor & Francis Group, LLC.
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.
Investigation of iron ores based on the bond grindability test
(2020) Harish, H.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Sinha, A.; Kumar, S.B.
Grinding is a process of reduction of lumps to powder depending on the requirement of particle size and particle shape. The present investigation involves the identify the physical properties of three different types of iron ores by using Bond ball mill. The result shows that the maximum Bond work index of 14 KWh/mt was obtained for 'A' type iron ore sample. The Bond work index for 'B' and 'C' type iron ore sample are of 11 and 10 KWh/mt. The variation of BWI of three iron ore sample may be varied during the geological formation of each iron ore sample. The output product of three iron ore sample composed of three different size fractions when ground in Bonds ball mill. Based on the BWI and output product size of three iron ore samples are classified as hard ore ('A' type iron ore sample), medium hard ore ('B' type iron ore sample) and soft ore ('C' type iron ore sample). The classification of different types of iron ore helps to run the plant scale ball mill by setting suitable operating parameters to the ball mill. � 2020 Author(s).
Investigation on the operational parameters of screening coal in the vibrating screen using Taguchi L27 technique
(Taylor and Francis Ltd., 2022) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.
In the present work, optimization of the newly developed vibrating screen’s operational parameters was carried out to obtain a high response parameter. The operational parameters considered in the present work were moisture content, angle, and frequency. The Taguchi L27 design technique was used to optimize three different operational parameters to obtain high screening efficiency of coal in the vibrating screen. The maximization of screening efficiency was obtained by selecting the “larger the better” condition for developing the model. The regression coefficient of 99.6% shows the close relationship between the predicted and experimental values. The lower value mean error and standard deviation of normal probability indicate that the developed model has less error. From the optimization results, it was clear that the 4% moisture content (low level), 1-degree angle (low level), and 9 Hz frequency (medium level) yielded high screening efficiency. Further, a confirmation test was carried out with the optimized condition, which has yielded a screening efficiency of 84.40%. The results showed that the Taguchi technique could be applied to study the influential operational parameters for maximizing the vibrating screen efficiency. © 2021 Taylor & Francis Group, LLC.
Maximum Aerobic Capacity and Relative Aerobic Strain among Mobile Mine Equipment Operators in Underground Mines
(Springer, 2023) Sridhar, S.; Raj, M.G.; Mangalpady, M.
The maximum aerobic capacity and relative aerobic strain could be employed as indicators to establish a balance between work and individuals. Unfortunately, information about the physiological demands of mobile mine equipment operators working in underground mines is nearly nonexistent. The present research aimed to determine the maximum aerobic capacity and relative aerobic strain of the mobile mine equipment operators and assess their relationship with their age and body mass index. Forty operators involved in transporting ore, overburden, mine personnel, explosives, repair material, etc., were examined. The maximum aerobic capacity was determined indirectly using the heart rate of the operators. The mean aerobic capacity of the operators was 38.75 mL/kg/min, and the lowest mean aerobic capacity was found in LHD operators, 37.98 ± 3.93 mL/kg/min. The maximum aerobic capacity was negatively correlated with age and body mass index. Eleven out of 40 operators had relative aerobic strain exceeding 50% of the maximum aerobic capacity. The mean relative aerobic strain was 46.9 ± 5.54, and the highest mean relative aerobic strain of 49.37 ± 5.55 was found among LHD operators. The relative aerobic strain had a positive correlation with age and BMI. Knowing the operators’ maximal capacities while executing their tasks could be crucial in assessing the physiological demands of individuals working in underground mines in terms of acceptable work constraints. © 2022, The Institution of Engineers (India).
Musculoskeletal Disorder Risk in the Upper Extremities of Mobile Mining Equipment Operators Exposed to Hand-Transmitted Vibrations in Underground Metal Mines: a Case–Control Study
(Springer Science and Business Media Deutschland GmbH, 2022) Sridhar, S.; Raj, M.G.; Mangalpady, M.
Hand-transmitted vibration (HTV) exposure is associated with various health risks for operators of mobile mining equipment (MME). The case–control research was conducted to determine the musculoskeletal disorder (MSD) risks associated with exposure to HTVs in the exposed (case) and non-exposed (control) groups. HTV readings were measured at the interface between the hand and the steering device using the SV 105B triaxial hand accelerometer connected to the SV106 human vibration analyzer involving 40 MME operators in accordance with ISO 5349:2001 guidelines. A questionnaire survey was also carried out among both the study groups using Cornell Musculoskeletal Discomfort Questionnaire. The European Union's 2002/44/E.C. was used to assess the health risks posed to the MME operators. Twenty-eight out of the 40 MMEs were generating HTVs exceeding the stipulated daily limits of vibration, putting 70% of the operators at increased risk for developing MSDs. The case group was found to have an elevated risk of exposure with odds ratio (OR) 7.56 (95% confidence interval (CI), 1.159, 49.39) and OR 12.80 (95% CI, 2.436, 67.285) times more likely than the control group to suffer discomfort in the left shoulder and left wrist, respectively, indicating increased risk of exposure to HTV. Additionally, cases had elevated risk associated with exposure to tobacco, OR 9.35(95% CI, 1.856, 47.129) compared to those who did not use tobacco. MSDs were more prevalent in the case group compared to the control group. This observation was validated by the field investigations and the responses of MME operators to the questionnaires. © 2022, Society for Mining, Metallurgy & Exploration Inc.
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.
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.