Faculty Publications
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Item Dynamic web service composition based on operation flow semantics(2010) D’Mello, D.A.; Ananthanarayana, V.S.Dynamic Web service composition is a process of building a new value added service using available services to satisfy the requester's complex functional need. In this paper we propose the broker based architecture for dynamic Web service composition. The broker plays a major role in effective discovery of Web services for the individual tasks of the complex need. The broker maintains flow knowledge for the composition, which stores the dependency among the Web service operations and their input, output parameters. For the given complex requirements, the broker first generates the abstract composition plan and discovers the possible candidate Web services to each task of the abstract composition plan. The abstract composition plan is further refined based on the Message Exchange Patterns (MEP), Input/Output parameters, QoS of the candidate Web services to produce refined composition plan involving Web service operations with execution flow. The refined composition plan is then transferred to generic service provider to generate executable composition plan based on the requester's input or output requirements and preferences. The proposed effective Web service discovery and composition mechanism is defined based on the concept of functional semantics and flow semantics of Web service operations. © 2010 Springer-Verlag Berlin Heidelberg.Item Influence of Ti, B and Sr on the microstructure and mechanical properties of A356 alloy(2011) Mallapur, D.G.; Kori, S.A.; Udupa, K.R.In the present investigation, the microstructural and mechanical properties study of A356 alloy have been discussed. The microstructural aspect of cast A356 alloy employed in the present study is strongly dependent on the grain refinement (Ti and B) and modification (Sr). The mechanical properties such as PS, UTS, %E, %R, YM and VHN have been investigated. This paper deals with the combined effect of grain refinement and modification, which improves the overall mechanical properties of the alloy. It is also a well-known fact that the mechanical properties of cast A356 alloy were improved by subjecting suitable melt treatment such as grain refinement, modification and mould vibration, etc. The quality of castings and their properties can be achieved by refining of ?-Al dendrites in A356 alloy by means of the addition of elements such as Ti and B which reduces the size of a-Al dendrites, which otherwise solidifies with coarse columnar a-Al dendritic structure. In addition, modification is normally adopted to achieve improved mechanical properties. Metallographic studies reveal that the structure changes from coarse columnar dendrites to fine equiaxed ones on the addition of grain refiner and further, plate like eutectic silicon to fine particles on addition of 0.20% of Al-10Sr modifier. The present result shows that a reduction in the size of a-Al dendrites, modification of eutectic Si and improvement in the mechanical properties were observed with the addition of grain refiner Al-3Ti, Al-3B and modifier Al-10Sr either individual addition or in combination. The change in the microstructure from coarse columnar ?-Al dendrites to fine equiaxed dendrites and plate like eutectic silicon to rounded particles leads to improved mechanical properties. © Springer Science+Business Media, LLC 2010.Item Influence of Ti, B and Sr on tribological properties of A356 alloy(2011) Mallapur, D.G.; Udupa, K.R.; Kori, S.A.The wear behaviour of an A356 alloy has been investigated in this paper. To understand the wear behaviour of the materials, the experiments were carried out using a pin on disc testing machine at various combinations of normal pressure, sliding speed and sliding distances. Tribological results reveal that weight loss of A356 alloy increases with increasing normal pressure and decreases with increasing sliding speed. Also, the results at microlevel revealed a structural change from coarse columnar dendrites to fine equiaxed ones on the addition of grain refiner (Al and B) and furthermore, plate-like eutectic silicon to fine particles on addition of modifier (Sr). It is further noted in the present study that addition of modifier does not disturb the influence of grain refiner and vice versa. Abrasive wear mechanism was interrupted by the formation of microwelds and later by oxidation of the Al matrix. © 2011 W. S. Maney & Son Ltd.Item Studies on the influence of grain refining and modification on microstructure and mechanical properties of forged A356 alloy(Elsevier Ltd, 2011) Mallapur, D.G.; Udupa, K.R.; Kori, S.A.Microstructure and mechanical properties of the forged A356 alloy have been investigated in this paper. Results reveals that at micro level forged structure was more refined than as in the as cast conditions. This is due to the work hardening effect, where the original structure is destroyed during the forging and recrystallization helped in creating large number of nucleating sites leading to fine grain structure. From the investigations on the mechanical properties, we deduce that the PS, UTS and hardness of forged materials are obviously higher than those of the ones treated with as cast condition without and with the addition of grain refiners and modifier. © 2011 Elsevier B.V.Item Refining of edible oils: A critical appraisal of current and potential technologies(Blackwell Publishing Ltd customerservices@oxonblackwellpublishing.com, 2015) Chandrasekar, C.; Charanyaa, S.; Belur, P.D.; Iyyaswami, I.Summary: The major sources of dietary lipids are edible oils, which include both vegetable and fish oils. Crude oil extracted from vegetable and fish sources contain mono-, di-, triacylglycerols along with impurities, which necessitates refining. The main objective of refining is to remove the contaminants that adversely affect the quality of oil, thereby reducing the shelf life and consumer acceptance. However, this refining process needs to be tailored as the composition of crude oil is highly variable, depending upon the plant/fish species, geographical location of the source and method of oil extraction. Recently, extensive efforts have been made to develop refining technology, using either conventional physical/chemical processes or several unconventional processes including biological and membrane processes. The first section of this review gives a brief description of general composition of some commonly used vegetable and fish oils, followed by the review of various refining methods and their effects on the oil constituents. Finally, an effort is made to understand the technological gaps in the existing methods and possible directions of research to overcome the said gaps. © 2014 Institute of Food Science and Technology.Item Effect of combined grain refinement and modification on microstructure and mechanical properties of hypoeutectic, eutectic and hypereutectic Al-Si alloys(Inderscience Publishers, 2015) Shivaprasad, C.G.; Kiran Aithal, K.; Narendranath, S.; Desai, V.; Mukunda, P.G.The effect of melt treatment owing to the combined addition of grain refiner and modifier on the microstructure and mechanical properties of Al-Si alloys having 7% (hypoeutectic), 12% (eutectic) and 15% silicon (hypereutectic) is studied. 1 wt. % of Al-1Ti-3B Master alloy was used as grain refiner. For modification of eutectic Si, 0.2 wt. % of Al-10Sr Master alloy was added to hypoeutectic alloy and 0.4 wt. % is added to eutectic alloy as well as hypereutectic alloy. Furthermore, refinement of primary Si in hypereutectic alloy was achieved by addition of 0.04 wt. % of phosphorus. The goal of this investigation is to determine the influence of combined addition of grain refiner and modifier on mechanical properties and qualitatively correlate with the microstructural changes. © 2015 Inderscience Enterprises Ltd.Item A new strategy to refine crude Indian sardine oil(Japan Oil Chemists Society yukagaku@jocs-office.or.jp, 2017) Charanyaa, S.; Belur, B.D.; Iyyaswami, R.Current work aims to develop a refining process for removing phospholipids, free fatty acids (FFA), and metal ions without affecting n-3 polyunsaturated fatty acid (n-3 PUFA) esters present in the crude Indian sardine oil. Sardine oil was subjected to degumming with various acids (orthophosphoric acid, acetic acid, and lactic acid), conventional and membrane assisted deacidification using various solvents (methanol, ethanol, propanol and butanol) and bleaching with bleaching agents (GAC, activated earth and bentonite) and all the process parameters were further optimized. Degumming with 5%(w/w) ortho phosphoric acid, two stage solvent extraction with methanol at 1:1 (w/w) in each stage and bleaching with 3% (w/w) activated charcoal loading, at 80ºC for 10 minutes resulted in the reduction of phospholipid content to 5.66 ppm from 612.66 ppm, FFA to 0.56% from 5.64% with the complete removal of iron and mercury. Under these conditions, the obtained bleached oil showed an enhancement of n-3 PUFA from 16.39% (11.19 Eicosapentaenoic acid (EPA) + 5.20 Docosahexaenoic acid (DHA)) to 17.91% (11.81 EPA + 6.1 DHA). Replacing conventional solvent extraction with membrane deacidification using microporous, hydrophobic polytetrafluoroethylene membrane (PTFE), resulted in a lesser solvent residue (0.25% (w/w)) in the deacidified oil. In view of lack of reports on refining of n-3 PUFA rich marine oils without concomitant loss of n-3 PUFA, this report is significant. © 2017 by Japan Oil Chemists’ Society.Item Transformation of refinery cracked naphtha stream into efficient lubricity improvers for ULSD(Springer, 2022) Sruthi, H.; Udayakumar, D.U.; Hegde, P.; Manjunatha, M.G.; Karthick, R.; Nandakumar, V.A new route for the conversion of refinery light cracked naphtha (LCN) stream into lubricity improvers for ultra-low sulphur diesel (ULSD) was developed through a simple chemical process involving olefin epoxidation and esterification reactions. Two different methods viz., H2O2/glacial acetic acid and m-chloroperbenzoic acid (m-CPBA), were found to be suitable for the epoxidation of LCN. The LCN epoxide was subjected to an esterification reaction via epoxide ring opening using different long chain (C4 - C18 alkyl groups) organic acids to get the hydroxy ester derivatives of LCN. The lubricating property of the newly synthesized hydroxy esters was studied by dosing them with ULSD at 300 and 150 ppm (wt/vol) concentrations. Amongst them, LCN hydroxy ester derived from stearic acid showed the best lubrication-enhancing property at both dosage levels. The scanning electron microscope (SEM) image and energy dispersive spectra (EDS) of the high-frequency reciprocating rig (HFRR) specimen support the lubricating action of the LCN esters through the formation of a protective layer between the metallic surfaces. The synergy of simple chemical processes and efficient lubricity action makes these LCN esters as promising materials for low-cost and scalable additives for ULSD. Graphical abstract: The olefin-rich light cracked naphtha obtained from the fluidized catalytic cracker unit of the oil refinery was converted into hydroxy esters through an epoxidation reaction followed by the esterification with different carboxylic acids. The hydroxy esters at low dosage levels (150/300 ppm) enhance the lubricating property of ultra-low sulfur diesel. [Figure not available: see fulltext.]. © 2022, Indian Academy of Sciences.Item Effect of Samarium (Sm) Addition on Microstructure and Mechanical Properties of AA5083 Alloy(Springer Science and Business Media Deutschland GmbH, 2024) Aravindh, G.; Kumar, G.V.P.; Udaya Bhat, K.Researchers are interested in reaping the potential benefits of incorporating small amounts of rare earth elements into aluminum alloys to attain finer grain size and to improve mechanical properties like toughness. This research investigates the effects of samarium (Sm) addition at concentrations of 0.5%, 1.0%, and 1.5% by weight on the microstructural and mechanical properties of AA5083 alloy. Optical microscopy (OM), field emission gun scanning electron microscopy (FEGSEM), X-ray diffraction (XRD), tensile testing machine (UTM), Vickers microhardness testing, and Charpy instrumented impact test were employed to evaluate the microstructure and mechanical properties of both as cast and solution treated (ST) samples. The samarium (Sm) is a beneficial grain refiner, leading to tailored properties in the AA5083 alloy. The results indicate that adding 1 wt% Sm generated significant enhancements in mechanical properties, such as tensile strength increased by 236 MPa and an elongation of 13.1% with a 27% reduction in grain size. However, incorporating 1.5 wt% Sm had an adverse impact on material properties, such as the grain size of the material increased by 22.73% and reduction in the tensile strength by 31%, corresponding to 1 wt% Sm added AA5083 alloy. Impact energy was reduced with the addition of Sm to the AA5083 alloy, both in as cast and ST samples. Furthermore, fractography was performed after impact and tensile testing. © American Foundry Society 2023.Item Comprehensive utilization of crustacean wastes by chemical-catalytic transformations using levulinic acid as a sustainable platform chemical(Springer Science and Business Media Deutschland GmbH, 2025) C, P.N.; Nowl, M.S.; Mandal, S.; Dutta, S.Shell residues from seafood processing and aquaculture industries encounter significant challenges in waste management. There are many traditional and emerging applications of shell waste, but their enormous scale of production outpaces the utilization. This work reports the comprehensive utilization of shell waste by sequentially converting their major components into value-added products by selective chemical transformations. The pigments were extracted using ?-valerolactone (GVL), a biorenewable solvent produced from carbohydrate-derived levulinic acid (LA). The protein component was separated from shells under hydrothermal conditions with or without using any inorganic base. The calcite component was then reacted with LA and formic acid to form calcium levulinate and calcium formate, promising dietary supplements and chemical feedstock. Finally, chitin was converted into LA (30 mol%) under optimized conditions (150 °C, 4 h). Separation and value-addition of the components of crustacean exoskeletons demonstrated in this work are scalable, the products are marketable, and the catalyst used is recyclable. LA produced from chitin is used as the reagent and for synthesizing GVL for a closed-loop biorefinery. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.