Akilu Yunusa-kaltungo and Jyoti K. Sinha
The purpose of this paper is mainly to highlight how a simplified and streamlined approach to the condition monitoring (CM) of industrial rotating machines through the application…
Abstract
Purpose
The purpose of this paper is mainly to highlight how a simplified and streamlined approach to the condition monitoring (CM) of industrial rotating machines through the application of frequency domain data combination can effectively enhance the eMaintenance framework.
Design/methodology/approach
The paper commences by providing an overview to the relevance of maintenance excellence within manufacturing industries, with particular emphasis on the roles that rotating machines CM of rotating machines plays. It then proceeds to provide details of the eMaintenance as well as its possible alignment with the introduced concept of effective vibration-based condition monitoring (eVCM) of rotating machines. The subsequent sections of the paper respectively deal with explanations of data combination approaches, experimental setups used to generate vibration data and the theory of eVCM.
Findings
This paper investigates how a simplified vibration-based rotating machinery faults classification method based on frequency domain data combination can increase the feasibility and practicality of eMaintenance.
Research limitations/implications
The eVCM approach is based on classifying data acquired under several experimentally simulated conditions on two different machines using combined higher order signal processing parameters so as to reduce CM data requirements. Although the current study was solely based on the application of vibration data acquired from rotating machines, the knowledge exchange platform that currently dominates present day scientific research makes it very likely that the lessons learned from the development of eVCM concept can be easily transferred to other scientific domains that involve continuous CM such as medicine.
Practical implications
The concept of eMaintenance as a cost-effective and smart means of increasing the autonomy of maintenance activities within industries is rapidly growing in maintenance-related literatures. As viable as the concept appears, the achievement of its optimum objectives and full deployment to the industry is still subjective due to the complexity and data intensiveness of conventional CM practices. In this paper, an eVCM approach is proposed so that rotating machine faults can be effectively detected and classified without the need for repetitive analysis of measured data.
Social implications
The main strength of eVCM lies in the fact that it permits the sharing of historical vibration data between identical rotating machines irrespective of their foundation structures and speed differences. Since eMaintenance is concerned with driving maintenance excellence, eVCM can potentially contribute towards its optimisation as it cost-effectively streamlines faults diagnosis. This therefore implies that the simplification of vibration-based CM of rotating machines positively impacts the society with regard to the possibility of reducing how much time is actually spent on the accurate detection and classification of faults.
Originality/value
Although the currently existing body of literature already contains studies that have attempted to show how the combination of measured vibration data from several industrial machines can be used to establish a universal vibration-based faults diagnosis benchmark for incorporation into eMaintenance framework, these studies are limited in the scope of faults, severity and rotational speeds considered. In the current study, the concept of multi-faults, multi-sensor, multi-speed and multi-rotating machine data combination approach using frequency domain data fusion and principal components analysis is presented so that faults diagnosis features for identical rotating machines with different foundations can be shared between industrial plants. Hence, the value of the current study particularly lies in the fact that it significantly highlights a new dimension through which the practical implementation and operation of eMaintenance can be realized using big data management and data combination approaches.
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Ajay Kumar Jaiswal and Pallab Sinha Mahapatra
Maintaining the turbine blade’s temperature within the safety limit is challenging in high-pressure turbines. This paper aims to numerically present the conjugate heat transfer…
Abstract
Purpose
Maintaining the turbine blade’s temperature within the safety limit is challenging in high-pressure turbines. This paper aims to numerically present the conjugate heat transfer analysis of a novel approach to mini-channel embedded film-cooled flat plate.
Design/methodology/approach
Numerical simulations were performed at a steady state using SST k – ω turbulence model. Impingement and film cooling are classical approaches generally adopted for turbine blade analysis. The existing film cooling techniques were compared with the proposed design, where a mini-channel was constructed inside the solid plate. The impact of the blowing ratio (M), Biot number (Bi) and temperature ratio (TR) on overall cooling performance was also studied.
Findings
Overall cooling effectiveness was always shown to be higher for mini-channel embedded film-cooled plates. The effectiveness increases with increasing the blowing ratio from M = 0.3 to 0.7, then decreases with increasing blowing ratio (M = 1 and 1.4) due to lift-off conditions. The mini-channel embedded plate resulted in an approximately 21% increase in area-weighted average overall effectiveness at a blowing ratio of 0.7 and Bi = 1.605. The lower uniform temperature was also found for all blowing ratios at a low Biot number, where conduction heat transfer significantly impacts total cooling effectiveness.
Originality/value
To the best of the authors’ knowledge, this study presents a novel approach to improve the cooling performances of a film-cooled flat plate with better cooling uniformity by using embedded mini-channels. Despite the widespread application of microchannels and mini-channels in thermal and fluid flow analysis, the application of mini-channels for blade cooling is not explored in detail.
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Abhishek Kumar Sinha, Aswini Kumar Mishra, Manogna RL and Rohit Prabhudesai
The objective of the study is to analyse the impact of research and development investment on the firm performance of “small” scale firms vis-a-vis “medium”-scale firms.
Abstract
Purpose
The objective of the study is to analyse the impact of research and development investment on the firm performance of “small” scale firms vis-a-vis “medium”-scale firms.
Design/methodology/approach
The dataset comprised of a balanced panel of 486 research and development conducting Indian manufacturing small and medium enterprises, constructed for the period of 2006–2017. Fixed Effects, Random Effects Model and Hausmann test were used to analyse the determinants of firm performance in manufacturing small and medium enterprises in India.
Findings
It was found that from firms’ research and development (R&D) investments in terms of performance could be attained if simultaneously internationalisation and higher capital intensity could be achieved.
Practical implications
Managers could pay specific attention to the antecedents of firm performance and calibrate their R&D investment, internationalisation efforts and capital intensity simultaneously to achieve higher growth and productivity. For policymakers, the results provide an insight into how the firms in both categories could be differently incentivised, such that resources are better utilised.
Originality/value
The study analysed the determinants of firm performance in small and medium-sized firms at a disaggregate level as well as at a sectoral level using fixed effects, random effects and lagged effects to arrive at novel results, which have important implications for their competitiveness.
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Aswini Kumar Mishra, Anil Kumar and Abhishek Sinha
Though Indian economy since 1980s has expanded very rapidly, yet the benefits of growth remain very unequally distributed. The purpose of this paper is to provide new evidence…
Abstract
Purpose
Though Indian economy since 1980s has expanded very rapidly, yet the benefits of growth remain very unequally distributed. The purpose of this paper is to provide new evidence about the shape, intensity and decomposition of inequality change between 2005 and 2012. The authors find that Gini, as a measure of income inequality, has increased irrespective of geographic regions.
Design/methodology/approach
Based on a recent distribution analysis tool, “ABG,” the paper focuses on local inequality, and summarizes the shape of inequality in terms of three inequality parameters (α, β and γ) to examine how the income distributions have changed over time. Here, the central coefficient (α) measures inequality at the median level, with adjustment parameters at the top (β) and bottom (γ).
Findings
The results reveal that at the middle of distribution (α), there is almost the same inequality in both the periods, but the coefficients on the curvature parameters β and γ show that there is increasing inequality in the subsequent period. Finally, an analysis of decomposition of inequality change suggests that though income growth was progressive, however, this equalizing effect was more than offset by the disequalizing effect of income reranking.
Research limitations/implications
This paper shows how it can be possible both for “the poor” to fare badly relatively to “the rich” and for income growth to be pro-poor.
Practical implications
This paper stresses the significance of inequality reduction.
Social implications
Inequality reduction is very much imperative in ending poverty and boosting shared prosperity.
Originality/value
Perhaps, this research work is first of its kind to examine the shape and decomposition of change in income inequality in India in recent years.
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Amita Majumder, Ranjan Ray and Kompal Sinha
The purpose of this paper is to extend the methodology proposed in Majumder et al. (2012) for the estimation of the item-specific purchasing power parities (PPPs) within…
Abstract
Purpose
The purpose of this paper is to extend the methodology proposed in Majumder et al. (2012) for the estimation of the item-specific purchasing power parities (PPPs) within countries, to the cross-country context. It estimates item-specific intra-country PPPs (i.e. spatial prices) and inter-country PPPs in a unified framework using unit records of household food expenditures from three Asian countries: India, Indonesia and Vietnam, covering contemporaneous time periods. The study addresses a key limitation of the International Comparison Program (ICP) exercise, namely, that it treats all countries, large and small, as homogeneous entities. Moreover, it directly calculates bilateral PPPs between countries based on their expenditure patterns and prices alone and directly estimates the price-level indices (PLI) and their standard errors, allowing formal tests of the hypothesis of PLI being unity. The usefulness of the estimated PPPs is illustrated by applying them to comparisons of real food expenditures between the three countries, and benchmarking the comparisons with those using the ICP PPPs.
Design/methodology/approach
The methodology is based on the fact that a spatial price index can be viewed as a true cost of living index (TCLI). Using a general cost function underlying the Rank 3 quadratic logarithmic systems, the TCLI is calculated for a reference utility level.
Findings
The study provides formal statistical tests of the hypothesis of item invariance of the PPPs. The usefulness of the proposed methodology is illustrated by applying the estimated PPPs in comparisons of food expenditures between subgroups in the three countries. The sensitivity of the expenditure comparisons to the use of item-wise PPPs underlines the need to provide price information on highly disaggregated PPPs to a much greater extent than the ICP has done to date.
Research limitations/implications
The choice of these three Asian countries was dictated by the fact that, though comparability of items between them remains an issue as with all cross-country comparisons. Also, in the absence of price data, this study followed the practice in Majumder et al. (2012, 2015a, 2015b) in using as proxies the raw unit values of the food items, but adjusted for quality and demographic factors using the procedure introduced by Cox and Wohlgenant (1986) and extended by Hoang (2009).
Practical implications
It addresses some limitations of the ICP, namely, ICP treats all countries as single entities with the purchasing power of the country’s currency assumed to be the same in all regions within the country, ICP uses the US dollar as the numeraire (this ignores the fact that the PPPs required in bilateral welfare comparisons between developing countries with vastly different consumption habits from the “international norm” are quite different from the ICP PPPs) and ICP uses distribution invariant prices to calculate PPPs, which overlooks the fact that the poor pay different prices from the “representative” individual.
Social implications
This study highlights the importance of estimating and using item-specific PPPs in cross-country comparisons by formally testing and rejecting the assumption of item invariant PPPs and by providing empirical evidence that they do make a difference to the welfare comparisons between countries. This study provides PPPs based on food items only, which may be more relevant for poverty comparisons.
Originality/value
It introduces, for the first time, the concept of item-specific PPPs between countries as estimable parameters and operationalizes this concept by using them in cross-country welfare comparisons.
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Gunjan Soni, Vipul Jain, Felix T.S. Chan, Ben Niu and Surya Prakash
It is worth mentioning that in supply chain management (SCM), managerial decisions are often based on optimization of resources. Till the early 2000s, supply chain optimization…
Abstract
Purpose
It is worth mentioning that in supply chain management (SCM), managerial decisions are often based on optimization of resources. Till the early 2000s, supply chain optimization problems were being addressed by conventional programming approaches such as Linear Programming, Mixed-Integer Linear Programming and Branch-and-Bound methods. However, the solution convergence in such approaches was slow. But with the advent of Swarm Intelligence (SI)-based algorithms like particle swarm optimization and ant colony optimization, a significant improvement in solution of these problems has been observed. The purpose of this paper is to present and analyze the application of SI algorithms in SCM. The analysis will eventually lead to development of a generalized SI implementation framework for optimization problems in SCM.
Design/methodology/approach
A structured state-of-the-art literature review is presented, which explores the applications of SI algorithms in SCM. It reviews 56 articles published in peer-reviewed journals since 1999 and uses several classification schemes which are critical in designing and solving a supply chain optimization problem using SI algorithms.
Findings
The paper revels growth of swarm-based algorithms and seems to be dominant among all nature-inspired algorithms. The SI algorithms have been used extensively in most of the realms of supply chain network design because of the flexibility in their design and rapid convergence. Large size problems, difficult to manage using exact algorithms could be efficiently handled using SI algorithms. A generalized framework for SI implementation in SCM is proposed which is beneficial to industry practitioners and researchers.
Originality/value
The paper proposes a generic formulation of optimization problems in distribution network design, vehicle routing, resource allocation, inventory management and supplier management areas of SCM which could be solved using SI algorithms. This review also provides a generic framework for SI implementation in supply chain network design and identifies promising emerging issues for further study in this area.
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Deepa George and Saurabh Sinha
The demand for higher bandwidth has resulted in the development of mm-wave phased array systems. This paper aims to explore a technique that could be used to feed the individual…
Abstract
Purpose
The demand for higher bandwidth has resulted in the development of mm-wave phased array systems. This paper aims to explore a technique that could be used to feed the individual antennas in a mm-wave phased array system with the appropriate phase shifted signal to achieve the required directivity. It presents differential Colpitts oscillators at 5 and 60 GHz that can provide differential output signals to the quadrature signal generators in the proposed phase shifter system.
Design/methodology/approach
The phase shifter system comprises a differential Colpitts voltage controlled oscillator (VCO) and utilizes the vector-sum technique to generate the phase shifted signal. The differential VCO is connected in the common-collector configuration for the 5-GHz VCO, and is extended using a cascode transistor for the 60-GHz VCO for better stability at mm-wave. The vector sum is achieved using a variable gain amplifier (VGA) that combines the in-phase and quadrature phase signal, generated from oscillator output using hybrid Lange couplers. The devices were fabricated using IBM 130-nm SiGe BiCMOS process, and simulations were performed with a process design kit provided by the foundry.
Findings
The measured results of the 5-GHz and 60-GHz VCOs indicate that differential Colpitts VCO could generate oscillator output with good phase noise performance. The simulation results of the phase shifter system indicate that the generation of signals with phases from 0° to 360° in steps of 22.5° was achieved using the proposed approach. A Gilbert mixer topology was used for the VGA and the linearity was improved by a pre-distortion circuit implemented using an inverse tanh cell.
Originality/value
The measurement results indicate that differential Colpitts oscillator in common-collector configuration could be used to generate differential VCO signals for the vector-sum phase shifter. The simulation results of the proposed phase shifter system at mm-wave show that the phase shift could be realised at a total power consumption of 200 mW.
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Avik Sinha, Arnab Adhikari and Ashish Kumar Jha
This study aims to analyze the socio-ecological policy trade-off caused by technological innovations in the post-COVID-19 era. The study outcomes are utilized to design a…
Abstract
Purpose
This study aims to analyze the socio-ecological policy trade-off caused by technological innovations in the post-COVID-19 era. The study outcomes are utilized to design a comprehensive policy framework for attaining sustainable development goals (SDGs).
Design/methodology/approach
Study is done for 100 countries over 1991–2019. Second-generation estimation method is used. Innovation is measured by total factor productivity, environmental quality is measured by carbon dioxide (CO2) emissions and social dimension is captured by unemployment.
Findings
Innovation–CO2 emissions association is found to be inverted U-shaped and innovation–unemployment association is found to be U-shaped.
Research limitations/implications
The study outcomes show the conflicting impact of technological innovation leading to policy trade-off. This dual impact of innovation is considered during policy recommendation.
Practical implications
The policy framework recommended in the study shows a way to address the objectives of SDG 8, 9 and 13 during post-COVID-19 period.
Social implications
Policy recommendations in the study show a way to internalize the negative social externality exerted by innovation.
Originality/value
This study contributes to the literature by considering the policy trade-off caused by innovation and recommending an SDG-oriented policy framework for the post-COVID-19 era.
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Soora Rasouli and Harry Timmermans
This chapter reviews models of decision-making and choice under conditions of certainty. It allows readers to position the contribution of the other chapters in this book in the…
Abstract
Purpose
This chapter reviews models of decision-making and choice under conditions of certainty. It allows readers to position the contribution of the other chapters in this book in the historical development of the topic area.
Theory
Bounded rationality is defined in terms of a strategy to simplify the decision-making process. Based on this definition, different models are reviewed. These models have assumed that individuals simplify the decision-making process by considering a subset of attributes, and/or a subset of choice alternatives and/or by disregarding small differences between attribute differences.
Findings
A body of empirical evidence has accumulated showing that under some circumstances the principle of bounded rationality better explains observed choices than the principle of utility maximization. Differences in predictive performance with utility-maximizing models are however small.
Originality and value
The chapter provides a detailed account of the different models, based on the principle of bounded rationality, that have been suggested over the years in travel behaviour analysis. The potential relevance of these models is articulated, model specifications are discussed and a selection of empirical evidence is presented. Aspects of an agenda of future research are identified.