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Machine Transliteration of Handwritten MODI Script to Devanagari using Deep Neural Networks
The transliteration process involves transcribing words from the source language into the target language that uses a different script. Language and scriptural hurdles can be overcome via transliteration systems. There is a demand for automated transliteration systems due to the existence of several languages and the growing number of multilingual speakers. This study focuses on the Machine Transliteration of handwritten MODI script to Devanagari. MODI script was the official script for Marathi till 1950. Although Devanagari has, since then, taken over as the Marathi languages official script, the MODI script has historical significance as large volumes of its manuscripts are preserved in libraries across different parts of India. However, MODI into Devanagari transliteration is a difficult task because MODI script documents are complex in nature and there is no standard dataset available for the experiment. Machine Transliteration can be approached either as a Natural Language Processing task or as a pattern recognition task. In this research work, the transliteration task is carried out using the pattern recognition technique. The transliteration of MODI script to Devanagari is implemented using Convolutional Recurrent Neural Network (CRNN) based Calamari OCR, which is open-source software. An accuracy of 88.14% is achieved in character level matching of each word in the MODI to Devanagari transliteration process. When considering the entire word matching, the accuracy achieved is 61%. Machine Transliteration of MODI script documents results in the retrieval of large repositories of knowledge from ancient MODI manuscripts. (2024), (Research Institute of Intelligent Computer Systems). All rights reserved. -
Machining Characteristics Evaluation of Al7075TiB2 In Situ Composite Using Abrasive Water Jet Machining with Varied Test Parameters
The study delves into the abrasive water jet (AWJ) cutting of an Al7075TiB2 metal matrix composite that was synthesized in situ. The primary goal is to investigate how variations in three key process parameters, namely, stand-off distance (SOD) ranging from 0.5 to 2.5mm, abrasive flow rate (100 to 300gmin), and traverse speed (100 to 500mmmin), affect three critical performance metrics: volumetric material removal rate (VMRR), dimensional accuracy, and surface roughness (SR). The study's findings were represented graphically, highlighting the relationships between these responses and the aforementioned process parameters. Scanning electron microscopy (SEM) was also used to examine the machined surfaces. It was discovered that increasing traverse speed resulted in significant increases in surface roughness, VMRR, and dimensional errors. An increase in the SOD, on the other hand, resulted in an increase in surface roughness, VMRR, and a decrease in dimensional accuracy. Furthermore, increasing the abrasive flow rate resulted in lower surface roughness and dimensional accuracy while achieving a higher VMRR. 2023, The Institution of Engineers (India). -
MADeGen: Multi-Agent based Deep Reinforcement Learning for Sequential Keyphrase Generation
Keyphrase generation is an essential tool in the field of natural language processing for information retrieval, document summarization, and text recommendation applications, extracting succinct and representative phrases from the text document. Traditional keyphrase extraction methods applied the supervised or unsupervised learning fail to capture the sequential keyphrase generation in a dynamic environment. The keyphrase generation approaches lack focus on explicitly discriminating the present and absent keyphrases, leading to the inadequate generation of semantically rich absent keyphrases. Hence, this work utilizes the potential benefits of reinforcement learning with the design of a distinguished reward function for present and absent keyphrases for sequential decision-making in the keyphrase generation. Thus, this work presents a novel keyphrase generation system, MADeGen, utilizing Multi- Agent Deep Reinforcement Learning (MADRL). In particular, a multi-agent reinforcement system collaboratively enables the generation of representative and coherent keyphrases by the evaluation metric-aware cooperative reward function analysis and adaptively training the agents. The proposed MADeGen incorporates two major phases, such as multi-agent modelling and actor critic-based policy optimization towards accurate keyphrase generation. In the first phase, the proposed approach designs two learning agents, including the extraction agent and generation agent, with the incorporation of a pre-trained language model. In the multi-agent system, the generation agent is the finetuned version of the extraction agent with the integration of the Wikipedia source. Secondly, the evaluation-aware adaptive reward function is designed to evaluate each agent's generated keyphrases with reference to ground-truth keyphrases. In subsequence, the cooperative reward analysis triggers the actor critic-based policy optimization for the generation agent in the multi-agent system to precisely generate the semantically relevant keyphrases with the assistance of an external web source. Experimental results on several benchmark datasets, such as Inspec, PubMed, and wiki20, illustrate the effectiveness of the proposed MADeGen compared to the existing keyphrase extraction models, yielding state-of-the-art performance in keyphrase extraction tasks. The proposed MADeGen proves its higher performance in the present as well as absent keyphrase extraction as 0.367 and 0.438 F1-score, respectively, while testing on the Inspec dataset. (2024), (Intelligent Network and Systems Society). All Rights Reserved. -
Magnetic coupling across the antiferromagnetic-antiferromagnetic interface
We investigate the magnetic coupling across the antiferromagnetic-antiferromagnetic (AFM-AFM) interface for the prototypical CoO-NiO bilayer system where the bulk Nl temperature (T N ) of NiO is higher than that of CoO. Using the temperature-dependent exchange-scattered electron intensities from the surface AFM lattice, the surface T N of CoO was estimated as a function of the CoO/NiO film thicknesses. Our results show that the surface T N of CoO layers is enhanced significantly from its bulk T N value and approaching the T N of the NiO layers, as the thickness of the CoO layers is reduced to the monolayer limit. Thus, thinner CoO layers are found to have higher T N than thicker layers on NiO, contrasting with the expected finite-size behavior. In addition to the short-range magnetic exchange coupling at the CoO-NiO interface, we observe the existence of a longer-range magnetic coupling across the interface, mediated by the magnetic correlations. Thus, the magnetic proximity effect is attributed to a combination of a short-range and a weaker long-range magnetic coupling, explaining the long AFM order propagation length in AFM-AFM superlattices and bilayers. Further, our results indicate a new approach to tune the AFM Nl temperature by varying the individual layer thickness of the bilayer system through the magnetic proximity effect. 2021 IOP Publishing Ltd. -
Magnetic field and light dependant supercapacitor behaviours of Mn3O4-rGO hybrid nanocomposites
Recently, hybrid nanostructures have been very promising candidates for energy generation and storage applications in nanotechnology. Here, Manganese Oxide (Mn3O4) decorated reduced graphene oxide (rGO) nanosheets hybrid composite was synthesised in chemical methods. The hybrid nanocomposite shows supercapacitance performance under a magnetic field and light irradiation. The magnetoelectrochemistry behaviour of the material was studied by varying external magnetic fields and the charge storage behaviours depending on the magnetic field. Additionally, the charge storage behaviour also changes under visible light irradiation. Interestingly, 82% enhancement is obtained under visible light. Therefore the present work gives a new pathway to understand the charge storage behaviour under light and magnetic fields. Qatar University and Springer Nature Switzerland AG 2024. -
Magnetic iron oxide nanoparticles immobilized on microporous molecular sieves as efficient porous catalyst for photodegradation, transesterification and esterification reactions
Magnetic iron oxide nanoparticles were immobilized on microporous molecular sieves (13X) via a plant extract mediated green synthesis method. The prepared material was then characterized using XRD, FTIR, TGA, FESEM, and TEM techniques. The synthesized iron oxide nanoparticles-molecular sieves (Fe2O3/MS) composite showed excellent photodegradation of methylene blue (MB) at 99% efficiency. Enhanced photocatalytic properties were observed in comparison with the pure iron oxide (Fe2O3) nanoparticles synthesized. Catalytic conversion of triglycerides to fatty-acid ethyl esters (FAEE) was carried out using sunflower oil, and the reaction showed very good catalytic activity in the transesterification of sunflower oil, converting 84% of the sunflower oil to FAEE. The catalyst was also used in the esterification reaction and found to have excellent applicability. The catalyst showed excellent reusability, and easy separation from the reaction mixture using an external magnet. This enables the synthesized material to act as a promising photocatalyst in degradation and organic synthesis. Very few reports are available on the synthesis of magnetic iron oxide coated on molecular sieves and used for photodegradation, transesterification, and esterification catalysis. 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Magnetic property applications of microwave method prepared zinc ion modified CoAl2O4 nanoparticles
Employing Microwave combustion technique and utilizing L-arginine as fuel pure Cobalt Aluminate and Zn doped Cobalt Aluminate nanoparticles (NPs) were prepared. XRD, DRS-UV, HRSEM and VSM techniques were used to investigate the structural, optical, morphological, and magnetic properties. The average crystallite size is found in the range of 15-24 nm. Elemental confirmation is done by aid of EDX spectra. The band gap values of the produced samples were discovered to be between 2.57 and 2.45 eV. At room temperature, the prepared samples showed diamagnetic magnetic characteristics, which were corroborated by MagnetizationField (MH) hysteresis curves. 2021, S.C. Virtual Company of Phisics S.R.L. All rights reserved. -
Magnetically retractable tea extract stabilized palladium nanoparticles for denitrogenative cross-coupling of aryl bromides with arylhydrazines under green conditions: An alternate route for the biaryls synthesis
Novel palladium based magnetic nanocatalyst was synthesized by the co-precipitation method and coated with silica and tea extract as stabilizing agent. Palladation onto the prepared nanocomposite was done to get ION-SiO2/TE-Pd(0) catalyst. Our study is one of the limited number of studies reported for the catalytic denitrogenative coupling of arylbromide and arylhydrazine. This led to the construction of important substituted biaryls bearing various substituents with 8292% yields. The synthesized nanocatalyst was characterized using structural and morphological characterization techniques. It was also observed that only 2 mol% of ION-SiO2/TE-Pd(0) catalyst was sufficient for the catalysis and reusable upto six cycles. 2024 The Authors -
Magneto convective flow of casson nanofluid due to Stefan blowing in the presence of bio-active mixers
The induced magnetic field for three-dimensional bio-convective flow of Casson nanofluid containing gyrotactic microorganisms along a vertical stretching sheet is investigated. The movement of these microorganisms cause bioconvection and they act as bio-active mixers that help in stabilising the nanoparticles in the suspension. The two forces, Thermophoresis and Brownian motion are incorporated in the Mathematical model along with Stefan blowing. The resulting model is transformed to ordinary differential equations using similarity transformations and are solved using (Formula presented.) method. The Velocity, Induced Magnetic field, Temperature, Concentration of Nanoparticles, and Motile density profiles are interpreted graphically. It is observed that the Casson parameter decreases the flow velocity and enhances the temperature, concentration, and motile density profiles and also it is noticed that the blowing enhances the nanofluid profiles whereas, suction diminishes the nanofluid profiles. On the other hand, it is perceived that the rate of heat conduction is enhanced with Thermophoresis and Brownian motion. IMechE 2021. -
Magneto-thermal-convection stability in an inclined cylindrical annulus filled with a molten metal
Purpose: Metal-cooled reactors generally use molten metals such as sodium, potassium or a combination of sodium and potassium because of their excellent heat transfer properties so that the reactor can operate at much lower pressures and higher temperatures. The purpose of this paper is to investigate the stability of natural convection in an inclined ring filled with molten potassium under the influence of a radial magnetism. Design/methodology/approach: A numerical simulation of electrically conductive fluid natural convection stability is performed on an inclined cylindrical annulus under the influence of a radial magnetism. The upper and lower walls are adiabatic, while the internal and external cylinders are kept at even temperatures. The equations governing this fluid system are solved numerically using finite volume method. The SIMPLER algorithm is used for pressure-speed coupling in the momentum equation. Findings: Numerical results for various effective parameters that solve the problem in the initial oscillatory state are discussed in terms of isobars, isotherms and flow lines in the annulus for a wide range of Hartmann numbers (0 ? Ha ? 80), inclination angles (0 ? ? ? 90) and radii ratios ? ? 6. The dependency stability diagrams between complicated situations with the critical value of the Rayleigh number RaCr and the corresponding frequency FrCr are established on the basis of the numeric data of this investigation. The angle of inclination and the radii ratio of the annulus have a significant effect on the stabilization of the magneto-convective flux and show that the best stabilization of the natural oscillatory convection is obtained by the intensity of the strongest magnetic field, the high radii ratio and inclination of the annulus at ? = 30. Practical implications: This numerical model is selected for its various applications in technology and industry. Originality/value: To the best of the authors knowledge, the influence of the inclination of the cylindrical annulus (ring), with various radii ratio, on natural oscillatory convection under a radial magnetism has never been investigated. 2020, Emerald Publishing Limited. -
Magneto-Thermo-Marangoni convective flow of Cu-H2O nanoliquid past an infinite disk with particle shape and exponential space based heat source effects
The exponential space dependent heat source (ESHS) process is utilized to explore the thermal transport characteristics of Marangoni convective flow in a Cu-H2O nanoliquid due to an infinite disk. Flow is driven by linear temperature. Five distinct nanoparticle shapes such as sphere, tetrahedron, column, hexahedron and lamina are accounted. Impacts of Joule heating, radiation and viscous dissipation are also retained. Hamilton-Crosser's expression is employed to deploy effective thermal conductivity of nanoliquid. Multi degree partial differential equations system is reduced by Km transformations and then solved via shooting method. It is figured out that the heat transfer rate is enhanced for stronger Marangoni convection and nanoparticle volume fraction. Also, shape of the nanoparticles significantly affects the flow fields. 2017 The Authors -
Magnetoconvection in a micropolar fluid
The problem of Rayleigh-Bard convection in an electrically conducting micropolar fluid layer permeated by a uniform, vertical magnetic field is investigated with free-free, isothermal, spin-vanishing boundaries. The influence of the various micropolar fluid parameters and magnetic field on the onset of stationary convection has been analysed. It is observed that the electrically conducting micropolar fluid layer heated from below is more stable as compared with the classical electrically conducting Newtonian fluid. The critical wave number is found to be insensitive to the changes in the micropolar fluid parameters, but sensitive to the Chandrasekhar number. 1998 Elsevier Science Ltd. All rights reserved. -
Magnetoconvection in fluids with suspended particles under 1g and ?g
The role of magnetic field in the inhibition of natural convection driven by combined buoyancy and surface tension forces in a horizontal layer of an electrically conducting Boussinesq fluid with suspended particles confined between an upper free/adiabatic and a lower rigid/isothermal boundary is considered in 1g and ?g situations. The inhibition of convection is caused by a stationary and uniform magnetic field parallel to the gravity field. The magnetically-inert suspended particles are not directly influenced by the magnetic field but are influenced indirectly by the magnetically responding carrier fluid in which they are suspended. A linear stability analysis of the system is performed. The Rayleigh-Ritz technique is used to obtain the eigenvalues. The influence of various parameters on the onset of convection has been analysed. Six different reference steady-state temperature profiles are considered and their comparative influence on onset is discussed. Treating Marangoni number as the critical parameter it is shown that any particular infinitesimal disturbance can be stabilized with a sufficiently strong magnetic field. It is observed that the electrically conducting fluid layer with suspended particles heated from below is more stable compared to the classical electrically conducting fluid layer without suspended particles. The critical wave number is found to be insensitive to the changes in the suspension parameters but sensitive to the changes in the Chandrasekhar number. The problem has possible space applications. 2002 itions scientifiques et micales Elsevier SAS. All rights reserved. -
Magnetohydro-convective instability in a saturated DarcyBrinkman medium with viscous dissipation
The influence of dissipation with viscosity on magnetohydro-convective instability in a saturated DarcyBrinkman medium is examined. The bottom boundary is designated as adiabatic, whereas the top boundary is isothermal. Numerical linear stability analysis investigates normal modes that disturb the horizontal base flow at different inclinations. The case study shows that the most unstable disturbances are horizontal rolls, normal modes characterized by a wave vector perpendicular to the main flow direction. The horizontal rolls are the favored instability mode. Barletta et al. also showed that horizontal rolls are more unstable than any other oblique roll mode in the hydromagnetic scenario. This finding provides insights into the behavior of MHD fluid flow and heat transfer in porous media, with implications for applications in geoscience, engineering, and environmental science. Graphical abstract: (Figure presented.) The Author(s), under exclusive licence to EDP Sciences, SIF and Springer-Verlag GmbH Germany, part of Springer Nature 2024. -
Magnetohydrodynamic flow of Carreau liquid over a stretchable sheet with a variable thickness: The biomedical applications
Purpose: The magnetohydrodynamic (MHD) flow problems are important in the field of biomedical applications such as magnetic resonance imaging, inductive heat treatment of tumours, MHD-derived biomedical sensors, micropumps for drug delivery, MHD micromixers, magnetorelaxometry and actuators. Therefore, there is the impact of the magnetic field on the transport of non-Newtonian Carreau fluid in the presence of binary chemical reaction and activation energy over an extendable surface having a variable thickness. The significance of irregular heat source/sink and cross-diffusion effects is also explored. Design/methodology/approach: The leading governing equations are constructed by retaining the effects of binary chemical reaction and activation energy. Suitable similarity transformations are used to transform the governing partial differential equations into ordinary differential equations. Subsequent nonlinear two-point boundary value problem is treated numerically by using the shooting method based on RungeKuttaFehlberg. Graphical results are presented to analyze the behaviour of effective parameters involved in the problem. The numerical values of the mass transfer rate (Sherwood number) and heat transfer rate (Nusselt number) are also calculated. Furthermore, the slope of the linear regression line through the data points is determined in order to quantify the outcome. Findings: It is established that the external magnetic field restricts the flow strongly and serves as a potential control mechanism. It can be concluded that an applied magnetic field will play a major role in applications like micropumps, actuators and biomedical sensors. The heat transfer rate is enhanced due to Arrhenius activation energy mechanism. The boundary layer thickness is suppressed by strengthening the thickness of the sheet, resulting in higher values of Nusselt and Sherwood numbers. Originality/value: The effects of magnetic field, binary chemical reaction and activation energy on heat and mass transfer of non-Newtonian Carreau liquid over an extendable surface with variable thickness are investigated for the first time. 2020, Emerald Publishing Limited. -
Magnetohydrodynamic flow of nano Williamson fluid generated by stretching plate with multiple slips
Purpose: The purpose of this paper is to present an exploration of multiple slips and temperature dependent thermal conductivity effects on the flow of nano Williamson fluid over a slendering stretching plate in the presence of Joule and viscous heating aspects. The effectiveness of nanoparticles is deliberated by considering Brownian moment and thermophoresis slip mechanisms. The effects of magnetism and radiative heat are also deployed. Design/methodology/approach: The governing partial differential equations are non-dimensionalized and reduced to multi-degree ordinary differential equations via suitable similarity variables. The subsequent non-linear problem treated for numerical results. To measure the amount of increase/decrease in skin friction coefficient, Nusselt number and Sherwood number, the slope of linear regression line through the data points are calculated. Statistical approach is implemented to analyze the heat transfer rate. Findings: The results show that temperature distribution across the flow decreases with thermal conductivity parameter. The maximum friction factor is ascertained at stronger magnetic field. Originality/value: In the current paper, the magneto-nano Williamson fluid flow inspired by a stretching sheet of variable thickness is examined numerically. The rationale of the present study is to generalize the studies of Mebarek-Oudina and Makinde (2018) and Williamson (1929). 2019, Emerald Publishing Limited. -
Magnetohydrodynamic flow of two immiscible hybrid nanofluids between two rotating disks
The two-layer model of the magnetohydrodynamic flow of hybrid nanofluid (HNF) between two disks of the same radii is analyzed in this study. The base fluids of both the hybrid nanofluids are immiscible so that these two fluids form an interfacial layer making the study more unique and innovative. The heat source/sink with viscous dissipation effect on energy equation is discussed. The governing equation is in the form of PDEs that are later reduced to ODEs with the help of the Von Karman transformation. The resulting ODEs are solved using the RK method and the results are interpreted graphically. In addition to temperature and concentration gradient, the radial, tangential and axial velocities for different parameters are studied. The results indicate that the physical ratios such as viscosity and thermal conductivity ratios can improve the fluid motion and temperature even in the presence of magnetic field. Also, the ratio of stretching rate produced by the rotation of disk can effectively control the fluid motion. The two fluid flow between two rotating disk forms an interfacial layer between the fluids results in the increment of heat transfer rate which finds application in the field such as heat ex-changer equipment, Cryogenic systems, electronic appliances, and solar collectors. 2024 Taylor & Francis Group, LLC. -
Magnetohydrodynamic flow of williamson nanofluid due to an exponentially stretching surface in the presence of thermal radiation and chemical reaction
A steady MHD boundary layer flow of Williamson nanofluid over an exponential stretching surface through a porous medium is considered. The effects of Brownian motion and thermophoresis have examined in the energy transport equation. The influences of solar radiation and chemical reaction are taken into the account. The governing boundary layer equations with the boundary conditions are transformed into nonlinear ordinary differential equations with the help of selected exponential type of similarity variables. They are then solved numerically using well-known Shooting technique along with Runge-Kutta-Fehlberg method. The numerical results are presented through graphs and a table to discuss the characteristics of different flow fields versus pertinent parameters. Comparisons with previously published work have been conducted and the results are found to be in good agreement. It is found that temperature field is enhanced for the larger Brownian motion, thermophoresis parameter and radiation parameter effects. 2017 by American Scientific Publishers. All rights reserved. -
Magnetohydrodynamic squeezing two-phase flow of particulate suspension in a rotating channel with transpiration cooling
This article addresses the time-dependent two-phase magnetohydrodynamic squeezing flow of dusty liquid. The fluid flow is considered in a rotating channel. The flow is constructed by squeezing of an upper plate and stretching of the lower plate and relevant equations are obtained. Numerical results are computed by utilizing shooting method along with the RKFehlberg scheme. The obtained solutions are validated by comparison with the existing analytical solutions. The effects of pertinent parameters on velocities of both phases are comprehensively discussed through graphical results. The numerical values of shear stress of both phases at lower and upper walls are also tabulated. Furthermore, the slope of the linear regression line through data points is determined in order to quantify the increase/decrease. Numerical simulations disclosed that the normal and transverse velocities are decreased due to stronger Coriolis force. It is also established that the velocities of the fluid phase are higher than that of the dust phase IMechE 2018. -
Magnetohydrodynamic three-dimensional flow of nanofluids with slip and thermal radiation over a nonlinear stretching sheet: a numerical study
A numerical simulation for mixed convective three-dimensional slip flow of water-based nanofluids with temperature jump boundary condition is presented. The flow is caused by nonlinear stretching surface. Conservation of energy equation involves the radiation heat flux term. Applied transverse magnetic effect of variable kind is also incorporated. Suitable nonlinear similarity transformations are used to reduce the governing equations into a set of self-similar equations. The subsequent equations are solved numerically by using shooting method. The solutions for the velocity and temperature distributions are computed for several values of flow pertinent parameters. Further, the numerical values for skin-friction coefficients and Nusselt number in respect of different nanoparticles are tabulated. A comparison between our numerical and already existing results has also been made. It is found that the velocity and thermal slip boundary condition showed a significant effect on momentum and thermal boundary layer thickness at the wall. The presence of nanoparticles stabilizes the thermal boundary layer growth. 2016, The Natural Computing Applications Forum.