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Assessment of Shear Stress Distribution in Meandering Compound Channels with Differential Roughness Through Various Artificial Intelligence Approach
Accurate prediction of shear stress distribution along the boundary in an open channel is the key to solving numerous critical engineering problems such as flood control, sediment transport, riverbank protection, and others. Similarly, the estimation of flow discharge in flood conditions is also challenging for engineers and scientists. The flow structure in compound channels becomes complicated due to the transfer of momentum between the deep main channel and the adjoining floodplains, which affects the distribution of shear force and flow rate across the width. Percentage sharing of shear force at floodplain (%Sfp) is dependent on the non-dimensional parameters like width ratio of the channel (?) , relative depth (?) , sinuosity (s) , longitudinal channel bed slope (So) , meander belt width ratio (?) , and differential roughness (?). In this paper, various artificial intelligence approaches such as multivariate adaptive regression spline (MARS), group method of data handling Neural Network (GMDH-NN), and gene-expression programming (GEP) are adopted to construct model equations for determining %Sfp for meandering compound channels with relative roughness. The influence of each parameter used in the model for predicting the %Sfp is also analyzed through sensitivity analysis. Statistical indices are employed to assess the performance of these models. Validation of the developed %Sfp model is performed for the experimental observations by conventional analytical models; to verify their effectiveness. Results indicate that the proposed GMDH-NN model predicted the %Sfp satisfactorily with the coefficient of determination (R2) of 0.98 and 0.97 and mean absolute percentage error (MAPE) of 0.05% and 0.04% for training and testing dataset, respectively as compared to GEP and MARS. The developed model is also validated with various sinuous channels having sinuosity 1.343, 1.91 and 2.06. 2021, The Author(s), under exclusive licence to Springer Nature B.V. -
Down syndrome detection using modified adaboost algorithm
In human body genetic codes are stored in the genes. All of our inherited traits are associated with these genes and are grouped as structures generally called chromosomes. In typical cases, each cell consists of 23 pairs of chromosomes, out of which each parent contributes half. But if a person has a partial or full copy of chromosome 21, the situation is called Down syndrome. It results in intellectual disability, reading impairment, developmental delay, and other medical abnormalities. There is no specific treatment for Down syndrome. Thus, early detection and screening of this disability are the best styles for down syndrome prevention. In this work, recognition of Down syndrome utilizes a set of facial expression images. Solid geometric descriptor is employed for extracting the facial features from the image set. An AdaBoost method is practiced to gather the required data sets and for the categorization. The extracted information is then assigned and used to instruct the Neural Network using Backpropagation algorithm. This work recorded that the presented model meets the requirement with 98.67% accuracy. 2021 Institute of Advanced Engineering and Science. All rights reserved. -
Prediction of Material Removal Rate and Surface Roughness in Hot Air Assisted Hybrid Machining on Soda-Lime-Silica Glass using Regression Analysis and Artificial Neural Network
Hybrid machining is a combination of conventional with the non-conventional process or two non-conventional processes. In the present work, an attempt has been made to combine hot air with a conventional cutting tool to form a novel Hot Air Assisted Hybrid Machining (HAAHM) for the machining of soda-lime-silica glass. The mathematical model for the Material Removal Rate (MRR) and Surface Roughness (Ra) using Regression Analysis (RA) and the Artificial Neural Network (ANN) models has been developed for the grooving process. The deviation of 8.24% and 7.70% were found in the prediction of MRR and Ra by regression analysis and the deviation of 1.89% and 1.70% for MRR and Ra using an artificial neural network model. The deviation between the predicted and the experimental results of both the models are found to be within the permissible limit. Higher predictive capabilities were observed in ANN model than the regression model. However, both models demonstrated good agreement with the MRR of soda-lime-silica glass by this hybrid machining process. 2020, Springer Nature B.V. -
Thermal, mechanical and ?-ray shielding properties of micro- and nano-Ta2O5 loaded DGEBA epoxy resin composites
In this work, we have investigated the synergistic effect of micro- and nano-Ta2O5 fillers in the epoxy matrix on the thermal, mechanical, and radioprotective properties of the composites. Morphological analysis revealed uniform dispersion of fillers in the matrix. Both the thermal stability and tensile properties of matrices have enhanced in the presence of fillers. Although the nanocomposites showed significantly higher tensile strength and Youngs modulus compared to micro-composites, the enhancement in these properties was predominant at low loadings. Dynamic mechanical analysis indicated good interfacial adhesion and positive reinforcing effect on the matrix even at higher loading (30 wt%) of nano-Ta2O5. ?-Ray attenuation studies performed in the energy range of 0.3561.332 MeV revealed better ?-ray shielding ability of nanocomposites compared to microcomposites at same weight fraction of fillers. In particular, ?-ray attenuation at 0.356 MeV for 30 wt% nano-Ta2O5 loaded epoxy composite was enhanced by around 13% compared to the microcomposite at the same loading. Increased surface-to-volume ratio of nanofillers and consequent increase in matrix-filler adhesion and radiation-matter interaction have manifested in an overall enhancement in the thermal, mechanical, dynamic mechanical, and radiation shielding characteristics of nano-Ta2O5/epoxy composites, proving them as promising ?-ray shields. 2021 Wiley Periodicals LLC. -
Study of classical Be stars in open clusters older than 100 Myr
We performed the slitless spectroscopic survey to identify classical Be (CBe) stars in open clusters older than 100 Myr. Observing a sample of 71 open clusters, we identified 13 CBe stars in 11 open clusters, one of, which (TYC 2679-432-1) is a new detection. The 13 CBe stars show both H? in emission and IR excess, which confirm that they possess gaseous circumstellar discs. Two more CBe stars are found to exhibit H? in absorption for the first time, indicating that might be passing through disc-less episode presently. The spectral-type estimation is done for all these 15 stars and it is noticed that they belong to B0.5B8 type. Moreover, we found that the distribution of our sample is peaking near late B-types as expected. 2021, Indian Academy of Sciences. -
Analysis of club convergence for economies: identification and testing using development indices
This paper attempts to identify club convergence using the procedure suggested by Phillips and Sul (Phillips and Sul, Econometrica 75:17711855, 2007, Phillips and Sul, J Appl Economet 24:11531185, 2009) based on GDP per capita for 102 countries across the globe for the time period 1996 through 2015. The results indicate the presence of five clubs with four countries belonging to the non- convergent group. After identifying the clubs, the study analyzed the transitional behaviors among the clubs. Finally, to understand the determinant of the club membership, we used the ordered logit model by considering the initial level of GDP, gross capital formation, growth rate of population, and four indices, namely social, governance, sustainability, and globalization as the explanatory variables. The results suggest that the initial level of GDP per capita, gross capital formation, social, governance, sustainability, and globalization are the major factors for determining the club. 2021, The Japan Section of the Regional Science Association International. -
Inhibitory potential of ferula assafoetida extract on L-type calcium channel protein revealed by zebrafish studies and molecular docking
Ferula assafoetida is a part of many herbal formulations and hence it is pertinent to check the safety of its components specially to growing embryos. Zebrafish (Danio rerio) is considered to be one of the best models to study human embryonic development and metabolic pathways as its genome is fully sequenced and it possesses easily detectable developmental properties. In present study, the embryos of Danio rerio were treated with different concentrations of methanolic extract of Ferula assafoetida (MEFA) and its effects were checked at different post fertilization periods. Decreased heart beat rates, shrinkage of the chorion wall and other developmental abnormalities leading to the death of the embryos were observed. The methanolic extract of Ferula assafoetida was subjected to GC-MS to determine the different compounds present. Cardiotoxicity of these compounds were studied as it is one of the important factors for the retraction of a drug from the market. Molecular docking studies with L-type calcium channel (LTCC), a protein important for cardiac functioning, showed strong binding to the phytochemicals in the extract, with the maximum binding affinity observed with 26-hydroxycholesterol. The study proves that the methanolic extract of Ferula assafoetida contains phytochemicals which have the potential to cause cardiotoxicity in zebrafish embryos by interfering with the functions of LTCC possibly leading to arrhythmia. Altogether, our data suggest that the usage of these extracts in drug formulations should be done with caution. This is also indicative of the possible cytotoxic effect of the extract which could be tapped in the search for anticancer drugs. 2021 Chemical Publishing Co.. All rights reserved. -
Cloud Dynamic Scheduling for Multimedia Data Encryption Using Tabu Search Algorithm
The cloud computing is interlinked with recent and out-dated technology. The cloud data storage industry is earning billion and millions of money through this technology. The cloud remote server storage is on-demand technology. The cloud users are expecting higher quality in minimal cost. The quality of service is playing a vital role in any latest technology. The cloud user always depends on thirty party service providers. This service provider is facing higher competition. The customer is choosing a service based on two parameters one is security and another one is cost. The reason behind this is all our personal data is stored on some third party server. The customer is expecting higher security level. The service provider is choosing many techniques for data security, best one is encryption mechanism. This encryption method is having many algorithms. Then again one problem is raised, that is which algorithm is best for encryption. The prediction of algorithm is one of major task. Each and every algorithm is having unique advantage. The algorithm performance is varying depends on file type. The proposed method of this article is to solve this encryption algorithm selection problem by using tabu search concept. The proposed method is to ensure best encryption method to reducing the average encode and decode time in multimedia data. The local search scheduling concept is to schedule the encryption algorithm and store that data in local memory table. The quality of service is improved by using proposed scheduling technique. 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Optimization of heat transfer in the thermal Marangoni convective flow of a hybrid nanomaterial with sensitivity analysis
The heat transfer rate of the thermal Marangoni convective flow of a hybrid nanomaterial is optimized by using the response surface methodology (RSM). The thermal phenomenon is modeled in the presence of a variable inclined magnetic field, thermal radiation, and an exponential heat source. Experimentally estimated values of the thermal conductivity and viscosity of the hybrid nanomaterial are utilized in the calculation. The governing intricate nonlinear problem is treated numerically, and a parametric analysis is carried out by using graphical visualizations. A finite difference-based numerical scheme is utilized in conjunction with the 4-stage Lobatto IIIa formula to solve the nonlinear governing problem. The interactive effects of the pertinent parameters on the heat transfer rate are presented by plotting the response surfaces and the contours obtained from the RSM. The mono and hybrid nanomaterial flow fields are compared. The hybrid nanomaterial possesses enhanced thermal fields for nanoparticle volume fractions less than 2%. The irregular heat source and the thermal radiation enhance the temperature profiles. The high level of the thermal radiation and the low levels of the exponential heat source and the angle of inclination (of the magnetic field) lead to the optimized heat transfer rate (Nux = 7.462 75). 2021, Shanghai University. -
Efficient chemical fixation of CO2from direct air under environment-friendly co-catalyst and solvent-free ambient conditions
The capture and conversion of CO2from direct air into value-added products under mild conditions represents a promising step towards environmental remediation and energy sustainability. Consequently, herein, we report the first example of a Mg(ii)-based MOF exhibiting highly efficient fixation of CO2from direct air into value-added cyclic carbonates under eco-friendly co-catalyst and solvent-free mild conditions. The bifunctional MOF catalyst was rationally constructed by utilizing an eco-friendly Lewis acidic metal ion, Mg(ii), and a nitrogen-rich tripodal linker, TATAB. The MOF possesses a high BET surface area of 2606.13 m2g?1and highly polar 1D channels decorated with a high density of CO2-philic sites which promote a remarkably high CO2uptake of 50.2 wt% at 273 K with a high heat of adsorption value of 55.13 kJ mol?1. The high CO2-affinity combined with the presence of a high density of nucleophilic and Lewis acidic sites conferred efficient catalytic properties to the Mg-MOF for chemical fixation of CO2from direct air under environment-friendly mild conditions. The remarkable performance of the Mg-MOF for the fixation of CO2from direct air was further supported by in-depth theoretical calculations. Moreover, the computational studies provided an insight into the mechanistic details of the catalytic process in the absence of any co-catalyst and solvent. Overall, this work represents a rare demonstration of carbon capture and utilization (CCU) from direct air under eco-friendly mild conditions. The Royal Society of Chemistry 2021. -
Unlocking the potential of biosynthesized zinc oxide nanoparticles for degradation of synthetic organic dyes as wastewater pollutants
The azo dyes released into water from different industries are accumulating in the water bodies and bioaccumulating within living systems thereby affecting environmental health. This is a major concern in developing countries where stringent regulations are not followed for the discharge of industrial waste into water bodies. This has led to the accumulation of various pollutants including dyes. As these developing countries also face acute water shortages and due to the lack of cost-effective systems to remove these pollutants, it is essential to remove these toxic dyes from water bodies, eradicate dyes, or generate fewer toxic derivatives. The photocatalysis mechanism of degradation of azo dyes has gained importance due to its eco-friendly and non-toxic roles in the environment. The zinc nanoparticles act as photocatalysts in combination with plant extracts. Plant-based nanoparticles over the years have shown the potential to degrade dyes efficiently. This is carried out by adjusting the dye and nanoparticle concentrations and combinations of nanoparticles. Our review article considers increasing the efficiency of degradation of dyes using zinc oxide (ZnO) nanoparticles and understanding the photocatalytic mechanisms in the degradation of dyes and the toxic effects of these dyes and nanoparticles in different tropic levels. 2021 The Authors -
The upper domatic number of powers of graphs
Let A and B be two disjoint subsets of the vertex set V of a graph G. The set A is said to dominate B, denoted by A ? B, if for every vertex u ? B there exists a vertex v ? A such that uv ? E(G). For any graph G, a partition ? = fV1; V2; : : : ; Vpg of the vertex set V is an upper domatic partition if Vi ? Vj or Vj ? Vi or both for every Vi; Vj ? ?, whenever i ? j. The upper domatic number D(G) is the maximum order of an upper domatic partition. In this paper, we study the upper domatic number of powers of graphs and examine the special case when power is 2. We also show that the upper domatic number of kth power of a graph can be viewed as its k-upper domatic number. 2021 Azarbaijan Shahid Madani University. -
Key Indicators of Corporate Financial Status: Empirical Evidence from Indian Industrial Sector
The present pandemic situation has led to the rise in the number of financially distressed companies in the Indian business ecosystem. Stakeholders, especially shareholders, unsecured and trade creditors who do not enjoy lien on company assets, should be extra cautious about the financial status of a company before making any investment or lending decision. The present study attempts to suggest the key indicators of corporate financial status after analysing 12 ratios from the financial statements of 162 sample companies for five financial years. The suggested key indicators can assist the shareholders and creditors in differentiating a financially distressed company from a financially sound company in the Indian industrial sector. 2021 SCMS Group of Educational Institutions. All rights reserved. -
Computational modeling of heat transfer in magneto-non-Newtonian material in a circular tube with viscous and Joule heating
Numerous industrial and engineering systems, like, heat exchangers, chemical action reactors, geothermic systems, geological setups, and many others, involve convective heat transfer through a porous medium. The diffusion rate, drag force, and mechanical phenomenon are dealt with in the DarcyForchheimer model, and hence this model is vital to study the fluid flow and heat transport analysis. Therefore, numerical simulation of the DarcyForchheimer dynamics of a Casson material in a circular tube subjected to the energy losses due to the viscous heating and Joule dissipation mechanisms is performed. The novelty of the present investigation is to scrutinize the convective heat transport characteristics in a circular tube saturated with DarcyForchheimer porous matrix by utilizing the non-Newtonian Casson fluid. The flow occurs due to the elongation of the surface of a tube with a uniform heat-based source/sink. The similarity solution of the nonlinear problem was obtained using dimensionless similarity variables. The effects of operating parameters related to the flow phenomena are analyzed. Further, the friction factor and Nusselt number are also analyzed in detail. The present flow model ensures no flow reversal and acts as a coolant of the heated cylindrical surface; the existence of the magnetic field, as well as an inertial coefficient,acts as the momentum-breaking forces, whereas Casson fluidity buildsit. The Joule heating phenomenon enhances the magnitude of temperature. The thermal field of the Casson fluid is higher at the surface of the circular pipe due to convective thermal conditions. 2021 Wiley Periodicals LLC. -
Extensive long-term verbal memory training is associated with brain plasticity
The human brain has a remarkable capacity to store a lifetime of information through visual or auditory routes. It excels and exceeds any artificial memory system in mixing and integrating multiple pieces of information encoded. In this study, a group of verbal memory experts was evaluated by multiple structural brain analysis methods to record the changes in the brain structure. The participants were professional Hindu pandits (priests/scholars) trained in reciting Vedas and other forms of Hindu scriptures. These professional Vedic priests are experts in memorization and recitation of oral texts with precise diction. Vedas are a collection of hymns. It is estimated that there are more than 20,000 mantras and shlokas in the four Vedas. The analysis included the measurement of the grey and white matter density, gyrification, and cortical thickness in a group of Vedic pandits and comparing these measures with a matched control group. The results revealed an increased grey matter (GM) and white matter (WM) in the midbrain, pons, thalamus, parahippocampus, and orbitofrontal regions in pandits. The whole-brain corelation analysis using length ofpost-training teachingduration showed significant correlation with the left angular gyrus. We also found increased gyrification in the insula, supplementary motor area, medial frontal areas, and increased cortical thickness (CT) in the right temporal pole and caudate regions of the brain. These findings, collectively, provide unique information regarding the association between crucial memory regions in the brain and long-term practice of oral recitation of scriptures from memory with the proper diction that also involved controlled breathing. 2021, The Author(s). -
Visible light photodegradation of organic dyes using electrochemically synthesized MoO3/ZnO
In this study, flake-like MoO3-ZnO composite was prepared using a simple and robust electrochemical setup. The composite was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, elemental analysis, X-ray photoelectron spectroscopy, thermogravimetric analysis, photoluminescence, zeta potential analysis, and electrochemical impedance study. The modified ZnO shows a remarkable catalytic activity towards the photodegradation of three potentially hazardous dyes, malachite green, crystal violet, and methylene blue. More than 95% of both malachite green and crystal violet degraded within 140 min under visible light irradiation. Scavenger studies reveal that OH radicals produced by the photo-separated charges on MoO3-ZnO are responsible for the degradation of all three dyes. The photoactive charge carriers show less recombination rate as evidenced by the photoluminescence spectrum due to the interparticle charge migration process. This work suggests a new versatile procedure for the synthesis of MoO3-ZnO composites and establishes its photocatalytic efficacy under visible light with three common pollutant dyes found in wastewater. Graphical Abstract: [Figure not available: see fulltext.] 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. -
Work-life balance amongst dental professionals during the COVID-19 pandemic -A structural equation modelling approach
The Coronavirus disease (COVID-19) outbreak in 2019, has shocked the entire world. As an effort to control the disease spread, the Indian government declared a nationwide lockdown on March 25th, 2020. As dental treatment was considered high risk in the spread of COVID-19, dentistry became one of the most vulnerable professions during this time. Dental professionals had to face job layoffs, salary cuts in professional colleges, closure of private clinics resulting in huge psychological, moral, and financial crises. Studies during the previous and present pandemics have shown mental issues among health care workers necessitating institutional reforms, along with early care and support. A balance in the work-life amongst professionals is the key to better efficiency and, was majorly affected during the COVID-19 pandemic lockdown due to sudden unexpected changes. Hence this study was conducted to understand the changes they underwent both at home and professional front with a hypothesis that physical and mental health, activities, relationship status, and workplace influence the work-life balance. Methods A pre-validated questionnaire survey was done on dentists across India. Structural Equation Modelling and path analysis were applied to the data collected. Results The results of the study supported the hypothesis that factors like physical and mental health, activities, relationship status, and workplace influenced the work-life balance directly. A significant imbalance was seen amongst the female dentists. Conclusion The present study proved the unpreparedness among dental professionals. Hence an evolutionary phase in every field with better working protocols, robust mental health support, and a focus on strategies to face future such emergencies is required. 2021 Pai et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. -
Linear and Global Stability Analyses on the Influences of Thermal Non-Equilibrium and Non-uniform Gravity Field on DarcyBrinkmanBard Convection
Global and linear stability analyses of DarcyBrinkmanBard convection in a liquid-saturated porous medium with a non-uniform gravity field using the local thermal non-equilibrium (LTNE) model are investigated. Linear and quadratic (parabolic) gravity field profiles are considered in the analysis. The OberbeckBoussinesq approximation is assumed to be a valid and the stationary mode of onset of convection is shown to be the preferred mode due to the validity of the principle of exchange of stabilities. Critical values of wavenumber and thermal Rayleigh number are obtained numerically using the higher-order Galerkin technique. The effect of an increase in the gravity fields strength is to delay the onset of convection, and to a growth in convective cell size. Further, linear convective profile is found to postpone convection compared to the quadratic one. Global stability ensures the existence of subcritical motions in the case of a non-uniform gravity field. In contrast, subcritical motions do not exist in constant gravity in LTE and LTNE situations. A non-uniform gravity field has a significant influence on the convective instability in a liquid-saturated high-porosity medium, lesser influence in the case of a low porosity medium and least in the case of a clear fluid layer. 2021, The Author(s), under exclusive licence to Springer Nature India Private Limited. -
Decoding HERO: Predicting psychological capital with subjective well-being
The positive psychology movement has gained momentum in recent years and organizations have ascribed great importance to employee well-being in light of the favorable outcomes associated with it. The widely researched Psychological Capital (PsyCap) has been consistently linked to well-being across a variety of contexts but a gap still exists in literature about what lies to the 'left' of psychological capital. The present study attempts to fill this gap by examining subjective well being components- positive and negative affect and life satisfaction, as potential antecedents of PsyCap. The Academic PsyCap questionnaire, the Positive and Negative Affect Schedule (PANAS) and the Satisfaction with Life Scale (SWLS) were administered to participants. Results confirmed the expected associations between affect and PsyCap-positive affect positively predicted PsyCap and its four constituents whereas negative affect emerged as a negative predictor of PsyCap and its dimensions. Life satisfaction positively predicted only individuals' total hope scores. Thus, highlighting the role of subjective well-being components as antecedents of PsyCap, these findings suggest that promoting higher positive affect and lower negative affect can do more than just make individuals feel good, rather, it can bolster their reservoirs of crucial psychological resources as well. 2021 Ecological Society of India. All rights reserved. -
TEMPO mediated electrochemical oxidation of 4-pyridinemethanol using Pd and Pt Co-deposited polyaniline modified carbon fiber paper
Co-deposition of palladium and platinum (PdPt) nanoparticles on the conducting polymeric ?lm of Polyaniline (PAn) modified carbon fiber paper (CFP) electrode was carried out by using eletrochemical method. The modified electrode has been used for the oxidation of 4-pyridinemethanol. The electrochemical properties of fabricated multi-layered ?lms on carbon fiber paper (Pd-Pt/PAn/CFP) were studied by electrochemical AC impedance spectroscopy and cyclic voltammetry (CV). Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) characterization technics were environmentally benign and sustainable are used to analyze the structural properties of modified multi-layered electrode. The relative sizes and distribution of the nanoparticles on the electrode surface were analyzed using Scanning electron microscopy (SEM) and optical profilometry characterization techniques. Electrochemical studies by CV showed that the PdPt/PAn/CFP electrode had better electrochemical activity similar to PAn/CFP and Bare CFP electrode towards extensive electrochemical oxidation of 4-pyridinemethanol in presence of TEMPO (2,2,6,6-Tetramethylpiperidinyl-1-oxyl) in aqueous acidic medium. 2021