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Design and optimization of the process parameters for friction stir welding of dissimilar aluminium alloys
Friction Stir Welding (FSW) is one of the unique solid state welding technique that is fast gaining importance because of its ability to produce strong joints. The friction stir welding technique is effectively used in this research to join 5 mm thick dissimilar aluminium alloys of AA 7075-O and AA 5052-O grade. The effect of tool pin profile and tool rotational speed on the mechanical properties like micro-hardness and tensile strength are studied by the optimized Design of Experiments (DOE). The experiments are designed based on L16 orthogonal array considering TAGUCHI techniques for four design parameters and four parametric levels. The outcomes of experimental techniques are tabulated and TAGUCHI analysis, Analysis of Variance (ANOVA) are carried out in Minitab software. From the experimental results and statistical techniques, the methodology is validated and the outcomes of the experiments are found to be in close agreement with the statistical results with the error less than 5% of the mean difference value. The optimized process parameters for better micro hardness are as follows: tool rotational speed of 1200 rpm, feed of 120 mm/min, tool offset of 1 mm, and cylindrical tapered pin tool profile; while the optimized design of process parameters for better tensile strength are as follows: tool rotational speed of 1400 rpm, feed of 120 mm/min, tool offset of 1 mm and cylindrical tapered pin profile. The design and optimization of the process parameters for friction stir welding of dissimilar aluminium alloys is necessary for high strength weld joints. 2021, Paulus Editora. All rights reserved. -
Opinion mining on newspaper headlines using SVM and NLP
Opinion Mining also known as Sentiment Analysis, is a technique or procedure which uses Natural Language processing (NLP) to classify the outcome from text. There are various NLP tools available which are used for processing text data. Multiple research have been done in opinion mining for online blogs, Twitter, Facebook etc. This paper proposes a new opinion mining technique using Support Vector Machine (SVM) and NLP tools on newspaper headlines. Relative words are generated using Stanford CoreNLP, which is passed to SVM using count vectorizer. On comparing three models using confusion matrix, results indicate that Tf-idf and Linear SVM provides better accuracy for smaller dataset. While for larger dataset, SGD and linear SVM model outperform other models. Copyright 2019 Institute of Advanced Engineering and Science. All rights reserved. -
A STRUCTURAL EQUATION MODELLING APPROACH TOWARDS TAXPAYERS PERCEPTIONS ON GOODS AND SERVICES TAX IN INDIA; [UMA ABORDAGEM DE MODELAGEM DE EQUAES ESTRUTURAIS PARA AS PERCEPES DOS CONTRIBUINTES SOBRE O IMPOSTO SOBRE BENS E SERVIS NA DIA]; [UN ENFOQUE DE MODELADO DE ECUACIONES ESTRUCTURALES HACIA LAS PERCEPCIONES DE LOS CONTRIBUYENTES SOBRE EL IMPUESTO SOBRE BIENES Y SERVICIOS EN LA INDIA]
Purpose: The Purpose of this article is to comprehend how Indian taxpayers perceive the goods and services tax. Theoretical Framework: India has completed five years after the successful implementation of Goods and Services Tax (GST). Many economic benefits were promised at the time of implementation of this tax regime. Thus, it becomes essential to understand tax payers perceptions by developing a strong framework that influences their perceptions. Design/Methodology/Approach: A descriptive study approach was adopted for this objective. 200 replies were obtained in total. Using SPSS Amos, structural equation modelling was utilised to assess the assumptions produced. Attitude, knowledge, Equity, and fairness of taxpayers served as exogenous factors, while taxpayer impression served as the dependent variable. The real-world implication is used as a mediating variable in order to examine the impacts. Findings: The findings of the research indicate that tax knowledge, Equity, and fairness impact tax attitudes. This study provides some useful recommendations for further research in this sector. Research Implications: This study considers tax knowledge, tax equity and fairness and tax attitudes to measure tax payers perception. However, tax rates, regular amendments, circulars, technology and other variables could also be considered by future researchers on this study. Originality/Value: Using a Structural Equation Modelling in understanding Tax Payers Perceptions was hardly adopted in these types of studies. Variables considered for this study were also unique. 2023 AOS-Estratagia and Inovacao. All rights reserved. -
Quality enhanced framework through integration of blockchain with supply chain management
Recently, there has been significant growth in the consumption of the most widely diversified Internet of Things (IoT) technological knowledge, and devices, which has resulted in an impact on not only electrical items and the agricultural and food industries (Agri-Food) supply chain networks. This has sparked intense curiosity about the development of information sharing that is reliable, traceable, and transparent, and also increased significant research and advancement efforts. Existing IoT-based trace & authenticity methods for agri-food distribution networks are constructed on top of centralized architectures, which creates the potential for significant issues such as data security, manipulation, and standard points of weakness. A creative and scraping methodological approach to implementing decentralized trust-free networks is represented by blockchain technologies, the decentralized blockchain technologies that underpin cryptocurrencies. The fault tolerance, data integrity, visibility, and complete tracing of saved transactional data, along with cohesive digital information of property resources and independent transactions implementations, are in fact features built into this digitalization. This study introduces Agri-BlockIoT, a completely decentralized blockchain-based traceable platform for managing a global agro-food distribution network that can seamlessly connect IoT systems that produce and consume digital information all along the distribution chain. We implemented a use caseto achieve transparency and traceability. Lastly, we analyzed and contrasted the implementations' capability in terms of delay, CPU, or network utilization. 2022 The Authors -
Optimization of Flexible Manufacturing Production Line System Based on Digital Twin
This research presents a revolutionary Digital Twin (DT)driven method aimed at quick customization of computerized industrial processes. The DT includes dual components, the semi-physical replication that transfers system information and gives data input to the subsequent clause, which is enhanced. The outcomes of the optimum section are returned directly to the semi-physical replication used for validation. The term Open-Architecture Machine Tool (OAMT) led to a fundamental class of machine tools that consists of a basic unified platform and many individually designed modules that may be quickly added or replaced away. Designers can dynamically modify the production system for responding to process planning by inserting personalized components into its OAMTs. Major enabling approaches, along with how to identical virtual and substantial systems and how to instantly bi-level program the invention size and efficiency of developed structures to accommodate sudden variations of goods, are explained. A real execution is done to demonstrate the efficacy of the method to achieve increased enactment of the system by minimizing the overhead cost of the recompose method by systematizing and quickly enhancing it. 2023, The Author(s), under exclusive licence to Springer Nature Singapore Pte Ltd. -
Influence of agricultural wastes on larval growth phases of the black soldier fly, Hermetia illucens (Diptera: Stratiomyidae): An integrated approach
Insects are an effective tool for converting nutrients in agricultural by-products into protein-rich biomass and compost. Black soldier fly (BSF) (Hermetia illucens) larvae are currently one of the insect species widely used as a protein source in aquafeed globally. Although much effort has been spent on the use of BSF in aquafeed, there is not much information on the biology of the insect, especially with the morphology of the BSF. This study aimed to evaluate the influence of various organic wastes, such as fruit wastes (FW) and vegetable wastes (VW), on different growth phases of BSF larva (BSFL), using morphometric and scanning electron microscopic examinations, and the composition of the compost produced, as well as a method for upscaling of larval production of BSFL. Faster growth was observed in BSFL fed with VW substrate (40 days) compared to the FW (46 days). Based on the morphometric measurements such as length, larval head length, total length etc., five larval stages, prepupal and pupal stage of BSFL were differentiated and described. In addition, SEM imaging of BSF mouth parts found that the mouth morphology of the BSF larvae and prepupal stage differed, and the BSF prepupa had reduced mouthparts. Also, the mandibular-maxillary complex was well developed than the BSF prepupa. BSFL larvae have proven to convert fruit and vegetable waste into high-quality residue fertilizer for the soil. The BSF compost showed optimum nitrogen, phosphorous, potassium, calcium and sulphur content. This research establishes a baseline knowledge and guidance on the BSF-rearing facilities. Author (s). Publishing rights @ ANSF. -
Characteristics of chitin extracted from different growth phases of black soldier fly, Hermetia illucens, fed with different organic wastes
Insect chitin was isolated from different life stages of the black soldier fly Hermetia illucens, such as instar stages, prepupae and pupae, reared separately on fruit and vegetable waste substrates after removal of fat, protein and minerals. Chitin yield was high in prepupae fed with vegetable waste (11.78 0.13%) followed by fruit waste (6.82 0.36%). The extracted chitin was compared with a commercial chitin from shrimp by Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and thermogravimetric analysis. The results revealed that both chitins from commercial shrimp source and the H. illucens had similar chemical structures and physicochemical properties indicating the H. illucens chitin samples to be of ?- chitin orientation type. With regards to the H. illucens samples, small physiochemical changes were noticed. Furthermore, the polymers derived from BSF are equivalent to commercial polymers in terms of purity and structural morphology, indicating their utility for industrial and medical applications. Thus, H. illucens prepupae is a promising alternative source of chitin. 2023, African Association of Insect Scientists. -
Valorization of agro-industrial fruit peel waste to fluorescent nanocarbon sensor: Ultrasensitive detection of potentially hazardous tropane alkaloid
Millions of tonnes of agro-industrial waste are generated each year globally, with the vast majority of it going untreated, underutilized, and disposed of by burning or landfilling, causing severe environmental distress and economic downturn. A practical solution to this global issue is to use green chemistry to convert this waste into value-added products. Accordingly, in the present study, agro-industrial orange peel waste was valorized into fluorescent nanodiamond-like carbon sensor via a green route involving hydrothermal treatment of microwave carbonized orange peel waste. The developed sensor, used for the fluorescence detection of potentially hazardous drug atropine sulfate, exhibits unique dual linearity over concentration ranges of 300 nM to 1 M and from 1 M to 10 M, as well as ultra-low sensitivity of 34.42 nM and 356.46 nM, respectively. Additionally, the sensor demonstrates excellent reproducibility, high stability, and satisfactory recovery when used to identify and quantify atropine sulfate in biological samples and commercially available pharmaceuticals, indicating promising multidisciplinary applications. [Figure not available: see fulltext.] 2021, Higher Education Press. -
Facile Synthesis of Few-Layer Graphene Oxide from Cinnamomum camphora
Abstract: This study presents a facile synthesis technique to produce few-layer graphene oxide from Cinnamomum camphora (Camphor L.). Camphor upon carbonization and chemical oxidation leads to the formation of few-layer graphene oxide sheets of around ten layers with a lateral size of 4.14 nm and stacking height of 3.10 nm. AFM and SEM analysis results reveal the wrinkled morphology of the graphene oxide sheets formed. The sharp G band and the relative intensity of the defect to the graphitic band in the Raman spectrum indicate the formation of nanocrystalline graphene oxide sheets with fewer defects. The FTIR spectrum and the deconvoluted C 1s XPS spectrum of graphene oxide synthesized reveal the presence of predominant sp2 hybridized carbon along with carbon bound to various oxygen functionalities. In brief, the formation of high-quality few-layer graphene oxide from an abundant, low-cost, and readily available botanical precursor is herein reported. 2021, Pleiades Publishing, Ltd. -
Extraction and characterization of wrinkled graphene nanolayers from commercial graphite
A report on the synthesis of wrinkled graphene nano carbon from bulk graphite is presented here. The obtained graphene nano carbon comprises mixed phase, sp2-sp3 bonded disordered carbon network. The as synthesized samples were intercalated by Hummer's method and are separated by centrifugation and sonication to obtain few layer graphene sheets. The structural and chemical changes of the nanostructure was elucidated by Raman spectroscopy, XRD, SEM-EDS, XPS, FTIR and UV-Vis-NIR spectroscopy. Raman spectra confirmed the existence of highly graphitized amorphous carbon with five peaks in the deconvoluted first order Raman spectrum. The IR and XPS analysis confirms the incorporation of functional groups to graphitic basal plane. There was a shift in the peaks position and intensity with intercalation. The synthesized graphene sheet is found to be in the graphite to nanocrystalline graphitic trajectory. The SEM analysis revealed the formation of large area wrinkled graphene sheets. The nanostructure formed is effortlessly scalable and ideally suitable for nano carbon composites based nano electronic devices and switches. -
Wrinkled graphene: Synthesis and characterization of few layer graphene-like nanocarbons from kerosene
Wrinkled graphene, derived from a facile thermal decomposition and chemical method, was subjected to various analysis techniques and the results have been reported here. Raman studies revealed the presence of highly graphitized amorphous carbon, which was evident by the appearance of five peaks in the deconvoluted first order spectrum. This result was very well corroborated by the XRD analysis. XPS and FT-IR spectra confirmed the incorporation of oxygen functionalities into the carbon backbone. AFM and SEM images of the sample disclosed a cluster of few-layer wrinkled graphene fragments. TEM images displayed a chain of nearly spherical aggregates of graphene, resembling nanohorns. The resistivity and sheet resistance of the sample were found to be low, making the obtained material a promising candidate for various device applications. Hence, kerosene soot proved to be an efficient precursor for facile synthesis of few layer graphene-like nanocarbon. 2016 Wroclaw University of Technology. -
Mesoporous onion-like carbon nanostructures from natural oil for high-performance supercapacitor and electrochemical sensing applications: Insights into the post-synthesis sonochemical treatment on the electrochemical performance
Although onion-like carbon nanostructures (OLCs) are attractive materials for energy storage, their commercialization is hampered by the absence of a simple, cost-effective, large-scale synthesis route and binder-free electrode processing. The present study employs a scalable and straightforward technique to fabricate sonochemically tailored OLCs-based high-performance supercapacitor electrode material. An enhanced supercapacitive performance was demonstrated by the OLCs when sonicated in DMF at 60 C for 15 min, with a specific capacitance of 647 F/g, capacitance retention of 97% for 5000 cycles, and a charge transfer resistance of 3 ?. Furthermore, the OLCs were employed in the electrochemical quantification of methylene blue, a potential COVID-19 drug. The sensor demonstrated excellent analytical characteristics, including a linear range of 100 pM to 1000 pM, an ultralow sensitivity of 64.23 pM, and a high selectivity. When used to identify and quantify methylene blue in its pharmaceutical formulation, the sensor demonstrated excellent reproducibility, high stability, and satisfactory recovery. 2021 The Author(s) -
A Congruent Approach to Normal Wiggly Interval-Valued Hesitant Pythagorean Fuzzy Set for Thermal Energy Storage Technique Selection Applications
Thermal energy is the energy from a substance in which molecules and atoms vibrate faster because of an increase in temperature. Thermal energy storage (TES) is an available energy resource for renewable energy platforms that enables them to meet sustainable technical requirements. The TES technique is divided into three categories; sensible TES, latent-heat TES, and thermo-chemical TES. The best of these techniques is selected in this research paper. Here the Interval-Valued Hesitant Pythagorean Fuzzy Set (IVPHFS) under the Normal Wiggly Mathematical Methodology is proposed and described for application to multi-criteria decision making (MCDM) technology. The MCDM methods, the Step-wise Weight Assessment Ratio Analysis (SWARA) method for determining weight values, and the Weighted Aggregated Sum Product Assessment (WASPAS) method for ranking alternative values are used employed here. The alternative values are selected based on the following criteria: capacity, efficiency, storage period, charging and discharging times, and cost 2021, Taiwan Fuzzy Systems Association. -
Role of corporate innovation and uncertainty in determining corporate investment of the firm: does financial constraint, executive risk preference and firm risk-taking ability play any role
Purpose: This paper aims to investigate the relationship between corporate innovation and the firms corporate investment. Further, the authors begin with the assertion that the relationship between corporate innovation and corporate investment is impacted by significantly a) uncertain periods, b) financial constraint, c) executives risk preference and d) firm risk-taking ability. Design/methodology/approach: This study has considered non-financial listed companies (774 firms) for the period spanning from 20102022. The authors use a fixed effect regression model within a panel data framework to examine the relationship between corporate innovation and investment. For robustness, the authors use system generalised methods of moments to investigate the relationship between corporate investment and corporate innovation across all the samples. Findings: This study finds a positive relationship between corporate innovation and corporate investment, which means when the firm tries to make some innovation, it will increase its expenditure on fixed assets. However, the positive relationship between corporate innovation and corporate investment reduces with uncertainty. Additionally, financial constraint plays a significant role in determining this relationship. Executives and firms with high risk-taking ability tend to be more inclined to make investments. Originality/value: The study is unique because it determines the impact of corporate innovation on corporate investment. The current literature is focused on corporate innovation and uncertainties. However, no light has been shed on the relationship between corporate innovation and investment. At the same time, the authors have introduced three more variables which play a significant role in determining the corporate innovation-investment relationship. , Emerald Publishing Limited. -
Cattaneo-Christov Theory to model heat flux effect on nanoliquid slip flow over a spinning disk with nanoparticle aggregation and Hall current
The heat transport of a nanoliquid on a spinning disk with velocity slip and thermal jump boundary conditions is modeled. The effects of external magnetism and the aggregation of nanoparticles are analyzed. The Cattaneo-Christov heat flux model and the Joule heating phenomenon are incorporated in the thermal analysis. The central composite design (CCD) of the response surface methodology is implemented to optimize heat transfer in the nanoliquid. The sensitivity of the heat transport is analyzed. The partial differential governing model is converted into a system of ordinary differential equations using a novel von Karmans transformation, the consequent system is solved numerically. The significance of physical operating parameters is analyzed through a detailed parametric study. Optimal levels of Hall parameter, Hartmann number, and Eckert number, that optimize the heat transport are determined. The Lorentz force expands the structure of the thermal layer and subsequently reduces the heat transport of the system. The Hall current improves the thickness of the velocity layer in the radial direction, while the thickness of the thermal layer is reduced. Viscous dissipation improves the thickness of the thermal boundary layer. The isothermal boundary condition causes less heat transport in the system than the temperature jump condition. 2022 Informa UK Limited, trading as Taylor & Francis Group. -
Nanofluid flow past a vertical plate with nanoparticle aggregation kinematics, thermal slip and significant buoyancy force effects using modified Buongiorno model
The flow of ethylene glycol-based titania nanoliquid passing through a vertical plate induced by significant buoyancy forces (nonlinear convection) is analyzed with quadratic thermal radiation and considering the aggregation kinematics of the nanoparticles. The nanoliquid is modeled accounting for thermo-migration, Brownian motion, and the effectual thermophysical properties. The realistic zero mass flux and thermal slip conditions are considered on the surface of the plate. In addition, the mechanisms of exponential space-related heat source (ESHS) and thermal-based heat source (THS) are incorporated. The finite-difference technique-based bvp5c routine is used to obtain the numerical solution of thenonlinear system of equations. The effects of the parameters are examined on the dimensionless profiles of velocity, temperature, heat transport rate, the volume fraction of nanoparticles, and streamlines. It was found that the aggregation of nanoparticles significantly advances the temperature field while the velocity field is reduced. The ESHS and THS modulations improve the thickness of the thermal boundary layer. The quadratic thermal convection aspect improves the velocity of nanoliquid. Furthermore, the effects of quadratic thermal radiation assist the growth of the thermal boundary layer. The present results are relevant to various thermal systems including flat plate solar collectors, heat exchangers, and nuclear reactors. 2021 Informa UK Limited, trading as Taylor & Francis Group. -
Boundary layer flow of magneto-nanomicropolar liquid over an exponentially elongated porous plate with Joule heating and viscous heating: a numerical study
Micropolar fluids are used in lubrication theory, thrust bearing technologies, cervical flows, lubricants, paint rheology, and the polymer industry. This study develops the numerical simulation of the magneto-Darcy flow of a polarized nanoliquid with Joule heating and viscous heating mechanisms on an exponentially elongated surface. The effects of linearized Rosseland radiation and temperature-dependent heat generation are considered. The flow is generated by an exponential form of elongation of a flexible sheet. The porous matrix and nanoparticle effects are characterized by the Darcy expression and the two-component Buongiorno model correspondingly. The resulting partial differential systems are solved numerically using the RungeKutta-based shooting technique to interpret the importance of key parameters in physical quantities. A direct comparison is made to validate the results. Our results demonstrated that arbitrary movement of the nanoparticles significantly advances the temperature profile by reducing the concentration of nanoparticles. Both Joule heating and viscous heating mechanisms improve the structure of the thermal boundary layer. The porous matrix reduces the velocity of the nanoliquid and thus the width of the velocity boundary layer is reduced. 2021, King Fahd University of Petroleum & Minerals. -
Significance of aggregation of nanoparticles, activation energy, and Hall current to enhance the heat transfer phenomena in a nanofluid: a sensitivity analysis
The mechanisms involved in the heat transport enhancement due to suspended nanoparticles are still unclear. Many studies have shown that nanoparticle aggregation is a key aspect of increasing nanofluid thermal conductivity. Nevertheless, the fractal dimension of nanoparticle aggregation will have a substantial impact on the nanofluids thermal conductivity. Therefore, the present study examines the influence of nanoparticle aggregation and Hall current on the nanoliquid flow past a spinning disk. The importance of Arrhenius activation energy is also investigated. A revised correlation for the aggregation mechanism is attained using the modified Krieger-Dougherty model (KD-model) and the Maxwell-Bruggeman model (MB-model). A similarity technique and finite difference method are used to construct the numerical solutions for the boundary value problem. The 2D plots and 3D surface plots are shown to investigate how different key parameters impact the velocity, temperature, and concentration fields. The study highlights that the Hall current has a beneficial effect on the fluid flow field. Higher activation energy leads to a productive chemical reaction which, improves the concentration layer. The thermal boundary for NPs aggregationis superior than to that withoutNPs aggregation, and the suspension of nanoparticles will have a favorable impact on the thermal layer. 2022 Informa UK Limited, trading as Taylor & Francis Group. -
Multiple solutions and stability analysis in MHD non-Newtonian nanofluid slip flow with convective and passive boundary condition: Heat transfer optimization using RSM-CCD
This study explores the effect of Williamson nanofluid in the presence of radiation and chemical reaction caused by stretching or shrinking a surface with convective boundary conditions. After implementing two-component model and Lie group theory, the transformed ODEs are solved using the RungeKutta DormandPrince (RKDP) shooting approach technique. The dual solutions are predicted for certain range of physical nanofluid parameters, such as Williamson parameter ((Formula presented.)), stretching/shrinking parameter ((Formula presented.)), and suction parameter ((Formula presented.)) with different slip (Formula presented.) and magnetic M parameters. Contour plots are generated for the stable branch of the Nusselt number ((Formula presented.)) for different combinations, providing insights into the heat transfer characteristics. The eigenvalue problem is solved in order to predict flow stability. The optimization of heat transfer in nanoliquid is conducted by RSM-CCD. The resulting quadratic correlation enables the prediction of the optimal Nusselt number for (Formula presented.), (Formula presented.), and (Formula presented.). This investigation is motivated by various applications including manufacturing processes, thermal management systems, energy conversion devices, and other engineering systems where efficient heat transfer iscrucial. 2023 Wiley-VCH GmbH. -
INVESTIGATION OF ANTECEDENTS AND CONSEQUENCES OF USEFULNESS IN ONLINE TRAVEL COMMUNITIES: THE MODERATING ROLE OF DECISION MAKING STAGE
This study examines the perceived usefulness (PU) of online discourse and the decision-making behavior of users in Online Travel Communities (OTCs). Partial least squares structural equation modeling (PLS-SEM) was used on secondary data available in OTCs in the form of 852 threads to empirically test the proposed integrated model. The antecedents of the perceived usefulness of online travel communities were found to be the argument quality and credibility. These influence the PU of user-generated content significantly and are helpful in information adoption in OTCs. The PU of OTC discourse positively impacts travelers' information adoption and decision-making. The current study offers implications for OTCs and online service providers for enhancing the usefulness of user-generated content in OTCs and social media sites, leading to online information use and travel decision-making. Prior literature has explored the nature and magnitude of the influence of electronic word-of-mouth (eWOM) on information adoption and intention to use information for travel purchases from users' perspectives and has investigated the PU of third-party travel sites. This paper is an effort to examine PU and decision-making by analyzing the User-Generated-Content (UGC) posted by the actual users. 2023 Akdeniz University Publishing House. All rights reserved.