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Article
Publication date: 27 June 2020

P. Suresh, P. Mathiyalagan and K.S. Srikanth

The article explores the effect of sintering temperature on the ferroelectric hysteresis behavior of the synthesized ceramic material Ba0.9Ca0.05Sr0.05T0.85Zr0.15O3 (BCSTZO). It…

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Abstract

Purpose

The article explores the effect of sintering temperature on the ferroelectric hysteresis behavior of the synthesized ceramic material Ba0.9Ca0.05Sr0.05T0.85Zr0.15O3 (BCSTZO). It describes how the sintering temperature and its holding time have effect on the polarization-electric field (P-E) loops which is an important characteristic of a ferroelectric material. From the P-E loops obtained, various representative parameters like remnant polarization and coercive field values were extracted and scaling results were systematically established using them.

Design/methodology/approach

The present article describes the establishment of scaling relations for coercive field (Ec), remnant polarization (Pr) and back switching polarization (Pbc) as a function of temperature which have been obtained from P-E loops sintered at various temperature and time. This is because sintering temperature plays a pivotal role in determining the hysteresis parameters.

Findings

The temperature dependent scaling of Ec and Pr at sintering temperature of 1400, 1425, 1450 and 1475 °C yields EcαT0.40, EcαT0.80, EcαT0.47, EcαT0.29 and PrαT−1.72, PrαT−1.55, PrαT−1.72, PrαT−1.69 respectively. Further the scaling relations for the samples sintered at 1450 °C at different time interval of 3, 4, 5 and 6 h was also established to bring the effect of sintering in switching the ferroelectric hysteresis parameters.

Originality/value

The findings of this work will prove beneficial for the researchers working in optimization of sintering parameters and will benefit researchers selecting best material among the fabricated samples for further property enhancement. The optimized sample could be explored for multifunctional applications ranging from pyroelectric voltage to piezoelectric energy harvesting. In addition to this, the scaling results help to understand the nature of ferroelectric parameters with sintering. This may open up new avenues for studying the scaling behavior of dynamic hysteresis in synthesized material by focusing on hysteresis area as a function of applied electric fields, frequency and temperature. This reason owes to the fact that electric field and frequency are important parameters for a number of applications like sensor, transducers and medical applications.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 1
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 7 August 2018

P. Suresh and T. Poongodi

In the current scenario, new materials are gaining popularity due to higher specific properties of strength and stiffness, increase in wear resistance, dimensional stability at…

73

Abstract

Purpose

In the current scenario, new materials are gaining popularity due to higher specific properties of strength and stiffness, increase in wear resistance, dimensional stability at higher temperature, etc. Subsequently, the need for precise machining has also been increased enormously. The purpose of this paper is to study the surface roughness during the turning of Al-10%SiC and Al-5%SiC-5%Gr composites under different cutting conditions.

Design/methodology/approach

Artificial neural network (ANN) has been effectively employed in solving problems with effortless computation in the areas such as fault diagnosis, process identification, property estimation, data smoothing and error filtering, product design and development, optimisation and estimation of activity coefficients. Response surface method is also used to analyse the problems involving a number of input parameters and their corresponding relationship between one or more measured dependent responses. Using Design Expert.8 evaluation software package, a simpler and more efficient statistical RSM model has been designed. RSM models are created by using 27 experimental data measurements obtained from different turning conditions of aluminium alloy composites.

Findings

In this work, the surface roughness during turning of Al-10%SiC and Al-5%SiC-5%Gr composites under different cutting conditions has been studied. The surface roughness value is proportional with the increase in feed rate and depth of cut while inversely proportional with the cutting speed. In all turning conditions, Al-10%SiC composite has lower surface roughness values than Al-5%SiC-5%Gr hybrid composite. An ANN and response surface models have been developed to predict the surface roughness of machined surface. The experimental results concur well with predicted models.

Originality/value

In the present trend, new materials are gaining popularity due to higher specific properties of strength and stiffness, increase in wear resistance, dimensional stability at higher temperature, etc. Subsequently, the need for precise machining has also been increased enormously. In this work, the surface roughness during turning of Al-10%SiC and Al-5%SiC-5%Gr composites under different cutting conditions has been studied.

Details

Multidiscipline Modeling in Materials and Structures, vol. 14 no. 5
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 12 December 2023

P.R. Suresh

This paper aims to determine the implications of Covid-19 on the livelihood of marine fishermen. It gives a concrete picture of how vulnerable communities like marine fishermen…

133

Abstract

Purpose

This paper aims to determine the implications of Covid-19 on the livelihood of marine fishermen. It gives a concrete picture of how vulnerable communities like marine fishermen are affected due to the lockdown policies. The paper examines these communities' present status and the extent of vulnerability during the post-Covid period.

Design/methodology/approach

The study uses an exploratory research design to find the solution to the research problem. 298 samples were collected and analysed within a sustainable livelihood theoretical framework. The scope of the study is limited to marine fishermen in Kerala, residing in six districts out of the nine coastal districts. The impact of the lockdown on income was analysed using paired t-test and results linked with the theory.

Findings

The study has done an empirical analysis for three periods: before lockdown, lockdown and after lockdown, to identify the impact of lockdown on marine fishermen. The study's significant findings are that these fishermen's livelihood is at risk during the post-lockdown period, and many families are moving into a “debt-trap”.

Research limitations/implications

Policymakers can develop appropriate policy strategies to enhance the livelihood assets of vulnerable communities to include them in a sustainable framework.

Originality/value

Only a few studies are highlighting the impact of Covid-19 on vulnerable communities in India. The effects of climate change on the marine ecosystem are already endangering marine fisher folks' livelihoods. In this light, it is vital to study the extent of the impact of income shock on the livelihood assets of marine fishermen due to the lockdown policy implemented in the State to prevent the spread of Covid-19.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-03-2023-0192

Details

International Journal of Social Economics, vol. 51 no. 8
Type: Research Article
ISSN: 0306-8293

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Article
Publication date: 6 September 2011

M. Vijaya Kumar, P. Sampath, S. Suresh, S.N. Omkar and Ranjan Ganguli

This paper seeks to present a feedback error learning neuro‐controller for an unstable research helicopter.

591

Abstract

Purpose

This paper seeks to present a feedback error learning neuro‐controller for an unstable research helicopter.

Design/methodology/approach

Three neural‐aided flight controllers are designed to satisfy the ADS‐33 handling qualities specifications in pitch, roll and yaw axes. The proposed controller scheme is based on feedback error learning strategy in which the outer loop neural controller enhances the inner loop conventional controller by compensating for unknown non‐linearity and parameter uncertainties. The basic building block of the neuro‐controller is a nonlinear auto regressive exogenous (NARX) input neural network. For each neural controller, the parameter update rule is derived using Lyapunov‐like synthesis. An offline finite time training is used to provide asymptotic stability and on‐line learning strategy is employed to handle parameter uncertainty and nonlinearity.

Findings

The theoretical results are validated using simulation studies based on a nonlinear six degree‐of‐freedom helicopter undergoing an agile maneuver. The neural controller performs well in disturbance rejection is the presence of gust and sensor noise.

Practical implications

The neuro‐control approach presented in this paper is well suited to unmanned and small‐scale helicopters.

Originality/value

The study shows that the neuro‐controller meets the requirements of ADS‐33 handling qualities specifications of a helicopter.

Details

Aircraft Engineering and Aerospace Technology, vol. 83 no. 5
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 March 2008

Yusuf Sahin and A. Riza Motorcu

This paper presents a study of the development of surface roughness model when turning the mild steel hardened up to 484 HV with mixed alumina ceramic (KY1615) and coated alumina…

263

Abstract

This paper presents a study of the development of surface roughness model when turning the mild steel hardened up to 484 HV with mixed alumina ceramic (KY1615) and coated alumina ceramic cutting tools (KY4400). The model was developed in terms of main cutting parameters such as cutting speed, feed rate and depth of cut, using response surface methodology. The established equation indicated that the feed rate affected the surface roughness the most, but other parametres remined stable for arithmetic average height parametre (Ra). However, it decreased with increasing the cutting speed, and with the starting and finishing point of cut for ten point height parametre (Rz). The cutting speed and the depth of cut had a slight effect on surface roughness values of Ra, Rz when using KY4400 cutting tools. Furthermore, the average surface roughness value of Ra was about 0.926 um, 1.089 um for KY1615, KY4400 cutting tools, respectively. The predicted surface roughness was found to be very close to experimentally observed ones at 95% confidence level. Moreover, analysis of variance indicated that squares terms were significant but interaction terms were insignificant for both cutting tools.

Details

Multidiscipline Modeling in Materials and Structures, vol. 4 no. 3
Type: Research Article
ISSN: 1573-6105

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Book part
Publication date: 4 December 2018

Indranarain Ramlall

Abstract

Details

The Banking Sector Under Financial Stability
Type: Book
ISBN: 978-1-78769-681-5

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Article
Publication date: 21 October 2021

Gullu Gencer, Hakan Atay, Arzu Gurdogan and Ulker Colakoglu

This study aims to measure the effect of organizational culture perceptions of hotel employees on their organizational silence behavior and job performance, as well as the effect…

2254

Abstract

Purpose

This study aims to measure the effect of organizational culture perceptions of hotel employees on their organizational silence behavior and job performance, as well as the effect of their organizational silence behavior on their job performance.

Design/methodology/approach

A correlational survey model was used in this research and a questionnaire was distributed to collect the data from 389 sampled employees working in four- and five-star hotels in the Kusadasi region in Turkey.

Findings

It was found that organizational culture was not significantly related to organizational silence but that organizational culture and its dimensions were significantly related to job performance. It was also revealed that while organizational silence was not significantly related to job performance, its dimensions were significantly related to job performance.

Practical implications

The results of this study provide insight into organizational culture as an important factor in increasing job performance. The study also revealed how organizational silence behavior and its dimensions affect job performance. In this sense, accommodation establishments will be able to acquire new perspectives in terms of improving job performance.

Originality/value

This paper is deemed important, as it examined these three terms in one model in the field of tourism management. It is thought that it will contribute to the literature by closing the gap in the tourism literature while leading the way for future studies.

Details

Journal of Hospitality and Tourism Insights, vol. 6 no. 1
Type: Research Article
ISSN: 2514-9792

Keywords

Available. Content available
Book part
Publication date: 11 January 2021

Farhad Analoui and Shehnaz Kazi

Free Access. Free Access

Abstract

Details

Managing NGOs in the Developing World
Type: Book
ISBN: 978-1-80043-782-1

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Article
Publication date: 23 May 2023

I. Aliyu, S.M. Sapuan, E.S. Zainudin, M.Y.M. Zuhri and Y. Ridwan

The conflicting results on the corrosion characteristics of aluminium matrix composites reinforced with agrarian waste have stimulated an investigation on the hardness and…

45

Abstract

Purpose

The conflicting results on the corrosion characteristics of aluminium matrix composites reinforced with agrarian waste have stimulated an investigation on the hardness and corrosion rate of sugar palm fibre ash (SPFA) reinforced LM26 Al/alloy composite by varying the SPFA from 0 to 10 wt% in an interval of 2 wt%. This paper aims to discuss the aforementioned issue.

Design/methodology/approach

The composites were produced via stir-casting and the hardness was determined using a Vickers hardness testing machine, corrosion rate was examined through the weight loss method by immersion in 0.5, 1.0 and 1.5 M hydrochloric acid (HCl) at temperatures of 303, 318, and 333 K for the maximum duration of 120 h. The morphological study was conducted using a scanning electron microscope (SEM) on the samples before and after immersion in HCl.

Findings

The incorporation of SPFA improved the hardness of the alloy from 58.22 to 93.62 VH after 10 wt% addition. The corrosion rate increases with increased content of SPFA, the concentration of HCl and temperature. The least corrosion rate of 0.0272 mpy was observed for the LM26 Al alloy in 0.5 M after 24 h while the highest corrosion rate of 0.8511 mpy was recorded for LM26 Al/10 wt% SPFA in 1.5 M HCl acid after 120 h. The SEM image of corroded samples revealed an increased number of pits with increased SPFA content.

Research limitations/implications

The work is limited to SPFA up to 10 wt% as reinforcement in LM26 Al alloy, the use of HCl as corrosion medium, temperatures in the range of 303–333 K, and a weight loss method were used to evaluate the corrosion rate.

Originality/value

The corrosion rate was determined for LM26 Al/SPFA composites with various amounts of SPFA in 0.5, 1.0 and 1.5 M HCl at 303, 318 and 333 K and compared with the matrix alloy.

Details

Multidiscipline Modeling in Materials and Structures, vol. 19 no. 4
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 24 October 2021

Sreenivasa Sekhar Josyula, M. Suresh and R. Raghu Raman

Organizations are fast adopting new technologies such as automation, analytics and artificial intelligence, collectively called intelligent automation, to drive digital…

1244

Abstract

Purpose

Organizations are fast adopting new technologies such as automation, analytics and artificial intelligence, collectively called intelligent automation, to drive digital transformation. When adopting intelligent automation, there is a need to understand the success factors of these new technologies and adapt agile software development (ASD) practices to meet customer expectations. The purpose of this paper is to explore the success factors of intelligent automation and create a framework for managers and practitioners to meet dynamic business demands. Total interpretive structural modeling (TISM) framework is a suitable approach to integrate quantitative measurement with qualitative semi-structured interviews capturing the context of the individual organization environment.

Design/methodology/approach

This paper identified agility factors and their interrelationships using a TISM framework. TISM results were validated using a one-tailed t-test to confirm the interrelationships between factors. Furthermore, the agility index of a case project organization was assessed using a graph-theoretic approach (GTA) to identify both the triggering factors for agility success and improvement proposals.

Findings

Results showed that leadership vision, organization structure and program methodology were driving factors. The TISM model was validated statistically and the agility index of the intelligent automation case project organization was calculated to be79.5%. Here, a GTA was applied and the triggering factors for improvement of the agility index were identified.

Research limitations/implications

The limitations of the study are described along with the opportunities for future research as the field evolves through the rapid innovation of technology and products.

Practical implications

The increasing role of digital transformation in enterprise strategy and operations requires practitioners to understand how ASD practices must be planned, measured and/or improved over time through the implementation of automation, analytics and artificial intelligence programs. The TISM digraph provides a framework of hierarchical structure to organize the influencing factors, which assists in achieving organizational goals. This study highlights the driving factors which contribute to the success of intelligent automation projects and project organizations.

Originality/value

This is a first attempt to analyze the interrelationships among agility factors in intelligent automation projects (IAP) using TISM and the assessment of the agility index of a case IAP organization using a GTA.

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