Ramesh Chand, Vishal S. Sharma, Rajeev Trehan and Munish Kumar Gupta
A nut bolt joint is a primary device that connects mechanical components. The vibrations cause bolted joints to self-loosen. Created by motors and engines, leading to machine…
Abstract
Purpose
A nut bolt joint is a primary device that connects mechanical components. The vibrations cause bolted joints to self-loosen. Created by motors and engines, leading to machine failure, and there may be severe safety issues. All the safety issues and self-loosen are directly and indirectly the functions of the accuracy and precision of the fabricated nut and bolt. Recent advancements in three-dimensional (3D) printing technologies now allow for the production of intricate components. These may be used technologies such as 3D printed bolts to create fasteners. This paper aims to investigate dimensional precision, surface properties, mechanical properties and scanning electron microscope (SEM) of the component fabricated using a multi-jet 3D printer.
Design/methodology/approach
Multi-jet-based 3D printed nut-bolt is evaluated in this paper. More specifically, liquid polymer-based nut-bolt is fabricated in sections 1, 2 and 3 of the base plate. Five nuts and bolts are fabricated in these three sections.
Findings
Dimensional inquiry (bolt dimension, general dimensions’ density and surface roughness) and mechanical testing (shear strength of nut and bolt) were carried out throughout the study. According to the ISO 2768 requirements for the General Tolerances Grade, the nut and bolt’s dimensional examination (variation in bolt dimension, general dimensions) is within the tolerance grades. As a result, the multi-jet 3D printing (MJP)-based 3D printer described above may be used for commercial production. In terms of mechanical qualities, when the component placement moves from Sections 1 to 3, the density of the manufactured part decreases by 0.292% (percent) and the shear strength of the nut and bolt decreases by 30%. According to the SEM examination, the density of the River markings, sharp edges, holes and sharp edges increased from Sections 1 to 3, which supports the findings mentioned above.
Originality/value
Hence, this work enlightens the aspects causing time lag during the 3D printing in MJP. It causes variation in the dimensional deviation, surface properties and mechanical properties of the fabricated part, which needs to be explored.
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Ramesh Chand Mittal and Sumita Dahiya
In this study, a second-order standard wave equation extended to a two-dimensional viscous wave equation with timely differentiated advection-diffusion terms has been solved by…
Abstract
Purpose
In this study, a second-order standard wave equation extended to a two-dimensional viscous wave equation with timely differentiated advection-diffusion terms has been solved by differential quadrature methods (DQM) using a modification of cubic B-spline functions. Two numerical schemes are proposed and compared to achieve numerical approximations for the solutions of nonlinear viscous wave equations.
Design/methodology/approach
Two schemes are adopted to reduce the given system into two systems of nonlinear first-order partial differential equations (PDE). For each scheme, modified cubic B-spline (MCB)-DQM is used for calculating the spatial variables and their derivatives that reduces the system of PDEs into a system of nonlinear ODEs. The solutions of these systems of ODEs are determined by SSP-RK43 scheme. The CPU time is also calculated and compared. Matrix stability analysis has been performed for each scheme and both are found to be unconditionally stable. The results of both schemes have been extensively discussed and compared. The accuracy and reliability of the methods have been successfully tested on several examples.
Findings
A comparative study has been carried out for two different schemes. Results from both schemes are also compared with analytical solutions and the results available in literature. Experiments show that MCB-DQM with Scheme II yield more accurate and reliable results in solving viscous wave equations. But Scheme I is comparatively less expensive in terms of CPU time. For MCB-DQM, less depository requirements lead to less aggregation of approximation errors which in turn enhances the correctness and readiness of the numerical techniques. Approximate solutions to the two-dimensional nonlinear viscous wave equation have been found without linearizing the equation. Ease of implementation and low computation cost are the strengths of the method.
Originality/value
For the first time, a comparative study has been carried out for the solution of nonlinear viscous wave equation. Comparisons are done in terms of accuracy and CPU time. It is concluded that Scheme II is more suitable.
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Shekhar Srivastava, Rajiv Kumar Garg, Vishal S. Sharma, Noe Gaudencio Alba-Baena, Anish Sachdeva, Ramesh Chand and Sehijpal Singh
This paper aims to present a systematic approach in the literature survey related to metal additive manufacturing (AM) processes and its multi-physics continuum modelling approach…
Abstract
Purpose
This paper aims to present a systematic approach in the literature survey related to metal additive manufacturing (AM) processes and its multi-physics continuum modelling approach for its better understanding.
Design/methodology/approach
A systematic review of the literature available in the area of continuum modelling practices adopted for the powder bed fusion (PBF) AM processes for the deposition of powder layer over the substrate along with quantification of residual stress and distortion. Discrete element method (DEM) and finite element method (FEM) approaches have been reviewed for the deposition of powder layer and thermo-mechanical modelling, respectively. Further, thermo-mechanical modelling adopted for the PBF AM process have been discussed in detail with its constituents. Finally, on the basis of prediction through thermo-mechanical models and experimental validation, distortion mitigation/minimisation techniques applied in PBF AM processes have been reviewed to provide a future direction in the field.
Findings
The findings of this paper are the future directions for the implementation and modification of the continuum modelling approaches applied to PBF AM processes. On the basis of the extensive review in the domain, gaps are recommended for future work for the betterment of modelling approach.
Research limitations/implications
This paper is limited to review only the modelling approach adopted by the PBF AM processes, i.e. modelling techniques (DEM approach) used for the deposition of powder layer and macro-models at process scale for the prediction of residual stress and distortion in the component. Modelling of microstructure and grain growth has not been included in this paper.
Originality/value
This paper presents an extensive review of the FEM approach adopted for the prediction of residual stress and distortion in the PBF AM processes which sets the platform for the development of distortion mitigation techniques. An extensive review of distortion mitigation techniques has been presented in the last section of the paper, which has not been reviewed yet.
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Ramesh Chand, Vishal S. Sharma, Rajeev Trehan and Munish Kumar Gupta
The purpose of this study is to find the best geometries among the cylindrical, enamel and honeycomb geometries based upon the mechanical properties (tensile test, compression…
Abstract
Purpose
The purpose of this study is to find the best geometries among the cylindrical, enamel and honeycomb geometries based upon the mechanical properties (tensile test, compression test and shear test). Further this obtained geometry could be used to fabricate products like exoskeleton and its supporting members.
Design/methodology/approach
The present research focuses on the mechanical testing of cylindrical, enamel and honeycomb-shaped parts fabricated through multi-jet printing (MJP) process with a wall thickness of 0.26, 0.33, 0.4 and 0.66 mm. The polymer specimens (for tensile, compression and shear tests) were fabricated using a multi-jet fusion process. The experimental results were compared with the numerical modelling. Finally, the optimal geometry was obtained, and the influence of wall thicknesses on various mechanical properties (tensile, compression and shear) was studied.
Findings
In comparison to cylindrical, enamel structures the honeycomb structures required less time to fabricate and had lower tensile, compressive and shear strengths. The most efficient geometry for fully functional parts where tensile, compressive and shear forces are present during application – cylindrical geometry is preferred followed by enamel, and then honeycomb. It was found that as the wall thickness of various geometries was increased, their ability to withstand tensile, compressive and shear loads also enhanced. The enamel shape structure exhibits greater strain energy storage capacity than other shape structures for compressive loads, and the strength to resist the compressive load will be lower. In the case of cylindrical geometries for tensile loading, the resisting area toward the loading will be higher in comparison to honeycomb- and enamel-based structures. At the same time, the ability to store the stain energy is less. The results of the tensile, compression and shear load finite element analysis using ANSYS are in agreement with those of the experiments.
Originality/value
From the insight of literature review, it is found that a wide range of work is done on fused deposition modeling (FDM) process. But in comparison to FDM, the MJP provide the better dimensional accuracy and surface properties (Lee et al., 2020). Therefore, it is observed that past research works not incorporated the effect of wall thickness of the embedded geometries on mechanical properties of the part fabricated on MJP (Gibson, n.d.). Hence, in this work, effect of wall thickness on tensile, compression and shear strength is considered as the main factor for the honeycomb, enamel and cylindrical geometries.
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Ramesh Chand Mittal, Sudhir Kumar and Ram Jiwari
The purpose of this study is to extend the cubic B-spline quasi-interpolation (CBSQI) method via Kronecker product for solving 2D unsteady advection-diffusion equation. The CBSQI…
Abstract
Purpose
The purpose of this study is to extend the cubic B-spline quasi-interpolation (CBSQI) method via Kronecker product for solving 2D unsteady advection-diffusion equation. The CBSQI method has been used for solving 1D problems in literature so far. This study seeks to use the idea of a Kronecker product to extend the method for 2D problems.
Design/methodology/approach
In this work, a CBSQI is used to approximate the spatial partial derivatives of the dependent variable. The idea of the Kronecker product is used to extend the method for 2D problems. This produces the system of ordinary differential equations (ODE) with initial conditions. The obtained system of ODE is solved by strong stability preserving the Runge–Kutta method (SSP-RK-43).
Findings
It is found that solutions obtained by the proposed method are in good agreement with the analytical solution. Further, the results are also compared with available numerical results in the literature, and a reasonable degree of compliance is observed.
Originality/value
To the best of the authors’ knowledge, the CBSQI method is used for the first time for solving 2D problems and can be extended for higher-dimensional problems.
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Several empirical studies have shown that the “servicization” of India ' s economy has taken place in terms of structural changes in GDP. But the structural changes in…
Abstract
Purpose
Several empirical studies have shown that the “servicization” of India ' s economy has taken place in terms of structural changes in GDP. But the structural changes in terms of employment have been slow, as agriculture is still the mainstay of more than 50 per cent of the total workforce. Though agriculture is still the predominant sector of the economy in terms of employment and livelihood, it is losing its dynamism. The country has been striving to achieve target of 4 per cent growth in agriculture since the 8th Five Year Plan so essential for achieving the objective of “inclusive growth”. However, the country is nowhere near the goal even in the penultimate year of 11th Five year Plan. The purpose of this paper is to emphasize the need for application of science and technology in India ' s agriculture to ensure sustainable development of agriculture with food security and also for tapping the “demographic dividend”. The agricultural crisis in India motivated the author to take up this study.
Design/methodology/approach
The present study mainly used secondary sources of data. The analysis of secondary data available in various documents, reports etc. revealed that agriculture in India is indeed passing through crisis. The review of literature revealed that science and technology can play a crucial role in rejuvenation of India ' s agriculture.
Findings
The paper shows that an integrated application of science and technology with social wisdom can help in checking the most serious form of brain-drain (i.e. migration of youth from rural to urban areas), mitigate the adverse impact of climate change and rejuvenate/revive India ' s agriculture so very essential for sustainability of India ' s growth, as has been stressed by Swaminathan.
Originality/value
The paper emphasizes the need for application of science and technology in India ' s agriculture to ensure sustainable development of agriculture with food security.
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This chapter presents a model of innovation in the public elementary schooling system by drawing on ongoing work on an “Educational Innovations Bank” in India, which seeks to make…
Abstract
This chapter presents a model of innovation in the public elementary schooling system by drawing on ongoing work on an “Educational Innovations Bank” in India, which seeks to make available a freely accessible forum for innovative teachers and a grassroots innovations resource for administrators. How do some teachers in government elementary schools, working in contexts of socioeconomic and educational deprivation, achieve their educational goals in spite of facing the same constraints as thousands of other teachers? What lessons do they offer for policy reform? The answers draw on the social entrepreneurship and workplace innovation literature to first locate the incentive for innovation in the social value that socio-educationally entrepreneurial and innovative behavior of teachers creates. Next, an examination is presented of how this social value leads to learning for an identity of competence, which in turn provides an incentive for further educational innovation. Finally, the evidence is presented to argue for policy entrepreneurship and a formal framework to help in the diffusion, adoption, and adaptation of both the enabling innovations that result from socio-educational entrepreneurship and the in-school or in-class educational innovations. Such a “bottom-up,” peer-learning-based approach to innovations that also “improve” provides a unique way of visualizing educational reform in resource-constrained public educational systems.
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Md. Abdur Rouf, Md. Nur-E-Alam Siddique and Md. Akhtaruddin
The study aims to identify, summarize and synthesize the theories used in corporate financial reporting (CFR) and propose a conceptual framework based on those theories.
Abstract
Purpose
The study aims to identify, summarize and synthesize the theories used in corporate financial reporting (CFR) and propose a conceptual framework based on those theories.
Design/methodology/approach
The study applied the systematic literature review approach to achieve the study objectives. So, the researchers systematically collected the relevant documents from the Scopus database with the help of an advanced search string containing keywords to the CFR theories. Preferred reporting items for systematic reviews and meta-analyses technique was used for the relevant document selection process. Finally, 67 documents were extracted and analyzed spanning from the year of 2017 to 2023.
Findings
The major findings of this study indicate a predominance of legitimacy, agency and stakeholder theories in CFR studies. Whereas, this study reveals that neo-institutional, signaling, resource dependency, political economics and impression management theories have been less focused on by scholars in the CFR studies. Those theories need to be reemphasized in this field in future research.
Originality/value
The study’s contributions are significant for academics, policymakers and different parties, as it enhance the understanding of CFR theoretical frameworks and suggest directions for future research to broaden the theoretical landscape. The study maps the motivations of applying a certain theory which will help the researchers to select a specific theory for the underlying context of CFR.
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Jenarthanan MP, Ramesh Kumar S. and Akhilendra Kumar Singh
This paper aims to perform an experimental investigation on the impact strength, compressive strength, tensile strength and flexural strength of fly ash-based green composites and…
Abstract
Purpose
This paper aims to perform an experimental investigation on the impact strength, compressive strength, tensile strength and flexural strength of fly ash-based green composites and to compare with these polyvinyl chloride (PVC), high density polyethylene (HDPE) and low density polyethylene (LDPE).
Design/methodology/approach
Fly ash-based polymer matrix composites (FA-PMCs) were fabricated using hand layup method. Composites containing 100 g by weight fly ash particles, 100 g by weight brick dust particles and 50 g by weight chopped glass fiber particles were processed. Impact strength, compressive strength, tensile strength and flexural strength of composites have been measured and compared with PVC, HDPE and LDPE. Impact strength of the FA-PMC is higher than that of PVC, HDPE and LDPE. Structural analysis of pipes, gears and axial flow blade was verified using ANSYS. Barlou’s condition for pipes, Lewis–Buckingham approach for gears and case-based analysis for axial flow blades were carried out and verified.
Findings
Pipes, gears and axial flow blades made form fly ash-based composites were found to exhibit improved thermal resistance (i.e. better temperature independence for mechanical operations), higher impact strength and longer life compared to those made from PVC, HDPE and LDPE. Moreover, the eco-friendly nature of the raw materials used for fabricating the composite brings into its quiver a new dimension of appeal.
Originality/value
Experimental investigation on the impact strength, compressive strength, tensile strength and flexural strength of fly ash-based green composites has not been attempted yet.
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Ramesh K.T., Sarada P. Sarmah and Pradeep Kumar Tarei
The purpose of this paper is to present a framework for identifying various inbound supply-risk factors and analyzing its indicators considering the contextual relationship…
Abstract
Purpose
The purpose of this paper is to present a framework for identifying various inbound supply-risk factors and analyzing its indicators considering the contextual relationship between them. This study additionally proposes a framework for developing an overall inbound supply-risk score considering a real-life case of the electronics supply chain (ESC) in the Indian context.
Design/methodology/approach
In total, 32 risk indicators are identified by a systematic literature review approach and are validated by supply chain practitioners/experts and further categorized into six main risk factors. A hybrid multi-criteria decision-making-based DANP (DEMATEL and ANP) framework is employed to develop the overall inbound-supply-risk score (ISRS) and to prioritize the risk indicators. Indian ESC is chosen as a viable case study to demonstrate the effectiveness of the proposed framework.
Findings
The outcomes from the study reveal that the overall ISRS in the ESC is 36 percent and additionally forewarns critical inbound-supply-risk factors such as supplier performance, product, and buyer organization. Further, the study also identifies the most significant risk indicators such as price margin, investment, on-time delivery, order fulfillment and design changes for ESC.
Research limitations/implications
Supply chain practitioners can adopt this framework as a useful inbound supply-risk assessment tool. Moreover, the hybrid framework will address subjectivity and interrelations among various factors through experts’ judgments. The results will assist the managers to have better insights on the critical risk factors and their complicated interrelationships and further strategize action plans to nullify the impact of incoming risks. This study mainly focused on risk identification and assessment of electronics inbound-supply-risk indicators in the Indian context. The framework can be used for other manufacturing and service industries, albeit the results derived are in the context of a developing country.
Originality/value
This paper provides an effective risk assessment framework for the supply chain practitioners/managers to develop a decision-support system for inbound-supply-risk quantification and prioritization of risk factors in the context of the ESC.