Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
8 results
Search Results
Item Making sense of high dimensional concrete data - A statistical approach(Institute of Physics Publishing helen.craven@iop.org, 2019) Manoj, A.; Babu Narayan, K.S.Performance of concrete is dependent on a number of factors. It is difficult to understand the influence and interrelationship among these variables, when there are many. Dimensionality reduction techniques can yield the best possible data interpretation based on the variance in data, without loss of much of original information. This paper presents the application of dimensionality reduction technique for analysis of data and decision making in the field of Concrete Technology. © Published under licence by IOP Publishing Ltd.Item Application of Proper Orthogonal Decomposition in Concrete Performance Appraisal(Springer Science and Business Media Deutschland GmbH, 2021) Manoj, A.; Babu Narayan, K.S.B.Mould ability of concrete has made it the most versatile and popular material of construction. Workability, strength and durability of concrete are very important characteristics that depend on a large number of variables like cement and aggregate type, mix proportioning, method of mixing, conveying, placing and curing and environmental conditions of exposure like temperature, humidity, wind velocity and insolation. The degrees to which workability, strength and durability characteristics vary, and also interplay and conflicts make decision on consideration of independent variables that influence concrete performance, make the job of analysts very complex. Proper Orthogonal Decomposition (POD) is a tool that has great usage potential in reorganizing and rationalizing vast data to understand dependence, interdependence and independence of variables that affect the concrete characteristics. This paper presents the utility of Proper Orthogonal Decomposition in concrete performance appraisal. © 2021, Springer Nature Singapore Pte Ltd.Item Influence of Ferrous Iron Addition on Silver Catalyzed Bioleaching of Copper from Chalcopyrite using an Isolated Acidithiobacillus Ferrooxidans Strain(Grenze Scientific Society, 2023) Bhaskar, S.; Manoj, A.; Nayak, D.M.; Furtado, I.M.; Anchan, D.; Wazir, A.M.Shake flask studies on influence of initial ferrous iron on bioleaching of copper from chalcopyrite using novel isolated bacterial strain Acidithiobacillus ferrooxidans BMSNITK17 with and without addition of silver catalyst was conducted and reported. Non-catalysed bioleaching of copper yields about 0.9 g/L of with 16 g/L of initial ferrous iron concentration while Silver catalysed bioleaching of copper from chalcopyrite yields about 1.6 g/L of copper with initial ferrous iron concentration of 4 g/L. Variation of pH, ferrous and ferric iron during the study were recorded and discussed. This study confirms the influence of initial ferrous iron concentration on bioleaching of copper. © Grenze Scientific Society, 2023.Item The utility of proper orthogonal decomposition for dimensionality reduction in understanding behavior of concrete(Techno-Press, 2021) Manoj, A.; Babu Narayan, K.S.B.Properties of wet and set concrete are influenced by a wide range of variables. With new formulations being tried and adopted, understanding workability, strength and durability characteristics of these formulations is of utmost importance. From among the wide range of variables that affect properties of concrete, identification of the most vital, interplay between variables, quantification of influence, for judicious manipulation of mix proportioning, placement, compaction and curing, to get the desired and targeted end results can vastly be improved by employing the state of the art data handling tools. Group method of data handling (GMDH), a set of mathematical algorithms, is of great usage potential in multi-variable data modeling, optimization and pattern recognition. Proper Orthogonal Decomposition (POD) a subset of GMDH, a technique for systematic dimensionality reduction and pattern recognition, is of great importance in studying complex datasets. This paper presents the need for adoption of GMDH techniques in concrete technology with an account of trends in this direction and also provides an illustration of POD’s utility as a valid decision-making tool in dimensionality reduction and projection of behavior of concrete subjected to elevated temperature. © 2021 Techno-Press, Ltd.Item Non-ferrous Fenton’s Oxidation of Ametryn Using Bioleached E-waste Copper as a Catalyst(Springer Science and Business Media Deutschland GmbH, 2022) Bhaskar, S.; Manoj, A.; Manu, B.; Sreenivasa, M.Y.; Mudipu, V.Shake flask study on bioleaching of copper from e-waste using novel isolated bacterial strain Acidithiobacillus ferrooxidans BMSNITK17 was conducted and reported. Under suitable conditions, about 77% of copper was recovered. The process was optimized with several influencing parameters like pulp density, pH, inoculum, temperature, and shake flask speed. To find the vital variables that affect copper dissolution, correlation studies and principal component analysis (PCA) were performed. Investigation on the application of recovered copper as a catalyst in Fenton’s oxidation of ametryn proved the catalytic role of copper with 87% of ametryn degradation efficiency. This study confirms the usage potential of acidophilic bacterial strain toward recovery of valuable metals from e-waste and its application as a catalyst in advanced oxidation process for the degradation of organic pollutants. Graphical Abstract: [Figure not available: see fulltext.] © 2022, The Minerals, Metals & Materials Society.Item Synthesis of plant-based biogenic jarosite nanoparticles using Azadirachta indica and Eucalyptus gunni leaf extracts and its application in Fenton degradation of dicamba(Editorial Office of Water Science and Engineering, 2024) Bhaskar, S.; Manu, B.; Sreenivasa, M.Y.; Manoj, A.Bio-jarosite, an iron mineral synthesized biologically using bacteria, is a substitute for iron catalysts in the Fenton oxidation of organic pollutants. Iron nanocatalysts have been widely used as Fenton catalysts because they have a larger surface area than ordinary catalysts, are highly recyclable, and can be treated efficiently. This study aimed to explore the catalytic properties of bio-jarosite iron nanoparticles synthesized with green methods using two distinct plant species: Azadirachta indica and Eucalyptus gunni. The focus was on the degradation of dicamba via Fenton oxidation. The synthesized nanoparticles exhibited different particle size, shape, surface area, and chemical composition characteristics. Both particles were effective in removing dicamba, with removal efficiencies of 96.8% for A. indica bio-jarosite iron nanoparticles (ABFeNPs) and 93.0% for E. gunni bio-jarosite iron nanoparticles (EBFeNPs) within 120 min of treatment. Increasing the catalyst dosage by 0.1 g/L resulted in 7.6% and 43.0% increases in the dicamba removal efficiency for EBFeNPs and ABFeNPs with rate constants of 0.025 min−1 and 0.023 min−1, respectively, confirming their catalytic roles. Additionally, the high efficiency of both catalysts was demonstrated through five consecutive cycles of linear pseudo-first-order Fenton oxidation reactions. © 2023 Hohai UniversityItem Effect of vehicular vibrations on L-4 lumbar vertebrae – A finite element study(Reed Elsevier India Pvt. Ltd., 2025) Kishore, Y.S.; Marulasiddappa, B.M.; Manoj, A.; Raveesh, R.M.; Rakesh, B.; Bhaskar, S.; Kuntoji, G.; Chethan, B.A.Lower Back Pain (LBP) is a global health issue, with increasing prevalence, partly attributed to vehicular vibrations experienced by motorcyclists. The L4 lumbar vertebra is responsible for greater mobility and flexibility of the body, but also is the most crucial body element affected by vehicular vibrations. Anthropometric properties, types of speed humps, and vehicle types are the critical variables that impact bone health during riding, need to be studied. To understand the potential zones of injury, computational simulation can be performed under the influence of vehicle vibrations while crossing different types of speed humps at varying speeds. In the present study, finite element method (FEM) is used to evaluate stress and deformation in the bone. The L4 cortical bone is modelled by considering the CT-Scan data and assumed to be homogeneous and isotropic material. Vibration data is collected using two vehicle types (Type I and Type II) on four different humps (Trapezoidal, Bitumen Semi-circular, Rubber Semi-circular, and Rumble strip). The bone's dynamic behavior is studied using FEM simulation, which involved static structural, modal and transient dynamic analyses. The findings from static analysis indicate that the most concentrated stress is located in the lower pedicle region and is an expected commonplace for injuries because of vibrations. In transient dynamic analysis, Type I vehicle showed a 25 % higher stress than Type II. © 2024 Professor P K Surendran Memorial Education FoundationItem Impact of sulfate supplement on bioleaching of iron from fly ash residue using isolated Acidithiobacillus ferrooxidans strain: A Box-Behnken process optimisation(Korean Society of Environmental Engineers, 2025) Bhaskar, S.; Apoorva, K.V.; Ashraf, S.; Shruthi, R.; Manoj, A.Fly ash, a residue from coal combustion contains significant iron content (10-40%), has potential applications in various fields. Present study investigated the impact of sulfate on bioleaching of iron from fly ash, using a novel Acidithiobacillus ferrooxidans strain. Iron dissolution obtained was 95.5 mg/L with 100 rpm shake flask speed, 3% pulp density, pH 3.0, and 5.5 g/L sulphate supplement, compared to 74.5 mg/L without sulphate over 15 days. The study employed Box-Behnken design for Design of Experiments. Variables ranged from 50 rpm – 150 rpm for shake flask speed, 2.5 – 3.5 for pH, 1% – 5% for pulp density, and 1.0 g/L – 10 g/L for sulfate concentration. In the experiment with sulfate supplement, the concentration of sulfate was treated as a variable parameter, as opposed to the pulp density, while taking into account other relevant characteristics. Iron dissolution was taken as a response. Pulp density and sulfate concentration significantly affected iron dissolution. A quadratic regression model was fit and an ANOVA was performed. According to the model, sulfate concentration has a positive linear influence with sulfate supplement, while for no sulfate supplement, shake flask speed and pulp density have a positive effect on the bioleaching of iron from fly ash. © 2025 Korean Society of Environmental Engineers.