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Article
Publication date: 20 December 2023

Indira Damarla, Venmathi M., Krishnakumar V. and Anbarasan P.

In this paper, a new front end converter (FEC) topology has been proposed for the switched reluctance (SR) motor drive. This study aims to present the performance analysis of…

Abstract

Purpose

In this paper, a new front end converter (FEC) topology has been proposed for the switched reluctance (SR) motor drive. This study aims to present the performance analysis of FEC-based SR motor drive using various types of control schemes like conventional proportional integral (PI) controller, fuzzy logic controller (FLC) and fuzzy-tuned proportional integral controller (Fuzzy-PI).

Design/methodology/approach

The proposed FEC-based SR motor drive with various control strategies is derived for the torque ripple minimization and speed control.

Findings

The steady state and the dynamic response of the FEC-based SR motor drive are analyzed using three different controllers under change in speed and loading conditions. The Fuzzy-PI-based control scheme improves the dynamic response of the system when compared with the FLC and the conventional PI controller.

Originality/value

The hardware prototype has been implemented for the FEC-based SR motor drive by using the Xilinx SPARTAN 6 FPGA processor. The experimental verification has been conducted and the results have been measured under steady state and dynamic conditions.

Details

Circuit World, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 8 July 2020

Anbarasan P., Krishnakumar V., Ramkumar S. and Venkatesan S.

This paper aims to propose a new MLI topology with reduced number of switches for photovoltaic applications. Multilevel inverters (MLIs) have been found to be prospective for…

174

Abstract

Purpose

This paper aims to propose a new MLI topology with reduced number of switches for photovoltaic applications. Multilevel inverters (MLIs) have been found to be prospective for renewable energy applications like photovoltaic cell, as they produce output voltage from numerous separate DC sources or capacitor banks with reduced total harmonic distortion (THD) because of a staircase like waveform. However, they endure from serious setbacks including larger number of capacitors, isolated DC sources, associated gate drivers and increased control difficulty for higher number of voltage levels.

Design/methodology/approach

This paper proposes a new three-phase multilevel DC-link inverter topology overpowering the previously mentioned problems. The proposed topology is designed for five and seven levels in Matlab/Simulink with gating pulse using multicarrier pulse width modulation. The hardware results are shown for a five-level MLI to witness the viability of the proposed MLI for medium voltage applications.

Findings

The comparison of the proposed topology with other conventional and other topologies in terms of switch count, DC sources and power loss has been made in this paper. The reduction of switches in proposed topology results in reduced power loss. The simulation and hardware show that the output voltage yields a very close sinusoidal voltage and lesser THD.

Originality/value

The proposed topology can be extended for any level of output voltage which is helpful for sustainable source application.

Details

Circuit World, vol. 47 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 28 February 2022

Jayarama Pradeep, Krishnakumar Vengadakrishnan, Anbarasan Palani and Thamizharasan Sandirasegarane

Multilevel inverters become very popular in medium voltage applications owing to their inherent capability of reconciling stepped voltage waveform with reduced harmonic distortion…

Abstract

Purpose

Multilevel inverters become very popular in medium voltage applications owing to their inherent capability of reconciling stepped voltage waveform with reduced harmonic distortion and electromagnetic interference. They have several disadvantages like more number of switching devices required and devices with high voltage blocking and need additional dc sources count to engender particular voltage. So this paper aims to propose a novel tri-source symmetric cascaded multilevel inverter topology with reduced number of switching components and dc sources.

Design/methodology/approach

A novel multilevel inverter has been suggested in this study, offering minimal switch count in the conduction channel for the desired voltage level under symmetric and asymmetric configurations. This novel topology is optimized to prompt enormous output voltage levels by employing constant power switches count and/or dc sources of voltage. The topology claims its advantages in generating higher voltage levels with lesser number of voltage sources, gate drivers and dc voltage sources.

Findings

The consummation of the proposed arrangement is verified in Matlab/Simulink R2015b, and an experimental prototype for 7-level, 13-level, 21-level, 29-level, 25-level and 49-level operation modes is constructed to validate the simulation results.

Originality/value

The proposed topology operated with six new algorithms for asymmetrical configuration to propel increased number of voltage levels with reduced power components.

Details

Circuit World, vol. 49 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 23 September 2021

Premkumar John, Rajeev Vamadevan Rajam, Rajkumar Mattacaud Ramachandralal and Krishnakumar Komalangan

The purpose of this study is to distinguish the difference in tribological behavior of functionally graded composites in two sliding modes, namely, unidirectional and…

Abstract

Purpose

The purpose of this study is to distinguish the difference in tribological behavior of functionally graded composites in two sliding modes, namely, unidirectional and reciprocating.

Design/methodology/approach

A356-(10 Wt.%)SiCp functionally graded composite material (FGM) was prepared by vertical centrifugal casting and then a comparison was made between the tribological characteristics using pin-on-disk and pin-on-reciprocating plate configurations under identical operating conditions (sliding distance (s): 350 m; load (W): 30 = W = 120 N, in steps of 30 N; and velocity (v): 0.2 = v = 1.2 m/s, in steps of 0.2 m/s). Two types of test pins were considered, namely, a test pin taken from the outer zone of the FGM with maximum particle concentration and a test pin taken from the inner zone of the FGM in a matrix-rich region.

Findings

The study revealed that, for the test pin taken from the outer zone of the FGM in the low-velocity range (0.2–0.4 m/s), the reciprocating wear of the friction pair was dominant, while unidirectional wear was dominant in the velocity range of 0.6–0.8 m/s for the entire load range investigated. However, when the velocity was increased from 1.0 to 1.2 m/s, conflicting nature of dominancy in the wear characteristics of the friction pair was observed, depending on the loading condition. In addition, the inner zone FGM pin underwent seizure in the reciprocating mode, whereas this phenomenon was not seen in the unidirectional mode.

Originality/value

Differences in wear and friction characteristics of FGM friction pairs in two different sliding modes were investigated over a wide range of operating parameters.

Details

Industrial Lubrication and Tribology, vol. 73 no. 8
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 9 February 2021

Judith Uchenna Chima and Temitope Omolayo Fasuan

Black turtle bean has nutritional potentials in the human diet and could provide a significant amount of food in developing countries. Low consumption of black beans has been…

Abstract

Purpose

Black turtle bean has nutritional potentials in the human diet and could provide a significant amount of food in developing countries. Low consumption of black beans has been attributed partly to the hard-to-cook phenomenon which requires a long time of cooking. Germination improves nutritional, functional, bioactive compounds, reduces anti-nutrients and cooking time. Germinated black turtle bean can contribute to efforts geared towards the production of functional foods and the fight against protein malnutrition. This study aims to investigate the changes in the nutritional, antioxidants and functional properties of black turtle bean due to different epigeal germination times to increase its utilization in food systems.

Design/methodology/approach

Black turtle bean seeds (Phaseolus vulgaris) were cleaned, winnowed, washed, soaked for 16 h, drained and subjected to epigeal germinated at ambient temperature for 0, 24, 48, 72 and 96 h, respectively. The germinated seeds were dried, dehulled, milled and sieved. Proximate, antioxidant properties and activity, anti-nutrients, mineral (calcium, phosphorus, iron, sodium, manganese, copper, potassium, zinc and magnesium) and functional properties (water absorption capacity, oil absorption, bulk density, swelling index, water solubility index and gelling concentration) of the germinated black turtle bean (GTB) flour (0GTB, 24GTB, 48GTB, 72GTB and 96GTB) were determined using standard procedures.

Findings

The ash, protein, fat and fibre contents of the black turtle bean were significantly increased through germination. Germination resulted in changes in the antioxidant activity of the black turtle bean samples. The mineral content of the black bean samples was improved significantly by germination and as well altered the functional properties (p < 0.01). Oxalate and phytate were significantly reduced with increased germination time (p < 0.01). In total, 96 h germination (96GTB) had better antioxidant activity, mineral and proximate composition with lower anti-nutrients.

Originality/value

Germination for 96 h proved to be the optimum time for improved mineral content, increased protein, ash, fibre, antioxidant activity and property with reduced antinutrients. Germination represents an attractive, inexpensive means of improving the nutritional profile and enhancing the bio-functionality of the black turtle bean. The epigeal germinated turtle bean could find applied as a functional ingredient in food formulation.

Details

Nutrition & Food Science , vol. 51 no. 7
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 23 August 2021

Murali Dasari, A. Srinivasula Reddy and M. Vijaya Kumar

The principal intention behind the activity is to regulate the speed, current and commutation of the brushless DC (BLDC) motor. Thereby, the authors can control the torque.

Abstract

Purpose

The principal intention behind the activity is to regulate the speed, current and commutation of the brushless DC (BLDC) motor. Thereby, the authors can control the torque.

Design/methodology/approach

In order to regulate the current and speed of the motor, the Multi-resolution PID (MRPID) controller is proposed. The altered Landsman converter is utilized in this proposed suppression circuit, and the obligation cycle is acclimated to acquire the ideal DC-bus voltage dependent on the speed of the BLDC motor. The adaptive neuro-fuzzy inference system-elephant herding optimization (ANFIS-EHO) calculation mirrors the conduct of the procreant framework in families.

Findings

Brushless DC motor's dynamic properties are created, noticed and examined by MATLAB/Simulink model. The performance will be compared with existing genetic algorithms.

Originality/value

The presented approach and performance will be compared with existing genetic algorithms and optimization of different structure of BLDC motor.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 14 no. 4
Type: Research Article
ISSN: 1756-378X

Keywords

Abstract

Details

Panel Data Econometrics Theoretical Contributions and Empirical Applications
Type: Book
ISBN: 978-1-84950-836-0

Article
Publication date: 2 December 2022

Farnoush Reshadi and Julian Givi

This study aims to add to the gift giving literature by examining how the wealth of a recipient impacts giver spending. The authors tested the hypotheses that givers spend more on…

Abstract

Purpose

This study aims to add to the gift giving literature by examining how the wealth of a recipient impacts giver spending. The authors tested the hypotheses that givers spend more on wealthy (vs unwealthy) recipients, partially because givers anticipate a greater difference in gift-liking across expensive and cheap gifts when the recipient is wealthy, and partially because givers are more motivated to signal that they are of high financial status when the recipient is wealthy. The authors also tested whether givers’ tendency to spend more on wealthy (vs unwealthy) recipients attenuates when the recipient is someone with whom the giver has a negative (vs positive) relationship.

Design/methodology/approach

Eight experimental studies tested the hypotheses. These studies had participants act as givers, consider giving a gift to either a wealthy or unwealthy recipient and indicate how much money they would spend on the gift. Some studies included additional measures to test potential mediators, while another included an additional manipulation to test a potential boundary condition.

Findings

Gift givers spend more on gifts for wealthy (vs unwealthy) recipients, for two main reasons. On the one hand, givers are influenced by an other-oriented motive – they wish for their gift to be well-liked by the recipient and anticipate a greater difference in recipient gift-liking across expensive and cheap gifts when the recipient is wealthy. On the other hand, givers are influenced by a self-oriented motive – they wish to signal to the recipient that they are of high financial status, but this desire is stronger when the recipient is wealthy. Critically, givers are relatively unlikely to spend more on wealthy (vs unwealthy) recipients when they have a negative (vs positive) relationship with the recipient.

Research limitations/implications

The authors studied how the wealth of the gift recipient influences givers’ gift expenditure, but they did not examine the recipient’s perspective. Future research could address this by exploring whether recipients’ gift preferences vary based on their wealth.

Practical implications

Gift purchases account for a significant portion of worldwide consumer spending, making gift giving an important topic for consumers and marketers alike. The present research sheds light on a factor that has a notable impact on how much consumers spend on a gift when faced with a gift giving decision.

Originality/value

This manuscript contributes to the gift giving literature by exploring an important aspect that influences consumer gift expenditure (the wealth of the recipient), demonstrating a novel gift giving phenomenon [that givers spend more when giving to relatively wealthy (vs unwealthy) recipients], and shedding new light on the psychology of consumers in gift giving contexts (namely, how givers’ perceptions of recipient gift-liking, their desire to send signals of high financial status and their relationship with the recipient can influence their gifting decisions).

Details

European Journal of Marketing, vol. 57 no. 2
Type: Research Article
ISSN: 0309-0566

Keywords

Article
Publication date: 14 February 2022

Cassandra Stawicki, Sukumarakurup Krishnakumar and Michael D. Robinson

This paper aims to examine whether work-related emotional intelligence (W-EI) benefits job performance among knowledge-intensive workers.

1066

Abstract

Purpose

This paper aims to examine whether work-related emotional intelligence (W-EI) benefits job performance among knowledge-intensive workers.

Design/methodology/approach

Postdoctoral researchers (Study 1) and industry researchers (Study 2) were recruited (total N = 304). These knowledge workers completed an ability-based emotional intelligence (EI) test and characterized their work-related performance. Potential moderators were also assessed.

Findings

There were positive relations between W-EI scores and both task performance and creative performance. In addition, these relationships were stronger in the context of higher levels of job negative affect and/or role overload.

Originality/value

To the best of the authors’ knowledge, these findings are among the first to demonstrate the value of the EI construct within a knowledge-intensive workforce.

Details

Journal of Knowledge Management, vol. 27 no. 2
Type: Research Article
ISSN: 1367-3270

Keywords

Article
Publication date: 1 February 2016

Alena Pietrikova, Peter Lukacs, Dagmar Jakubeczyova, Beata Ballokova, Jerzy Potencki, Grzegorz Tomaszewski, Jan Pekarek, Katerina Prikrylova and Martin Fides

This paper aims to find an optimal surface treatment of commonly used polymeric substrates for achieve the high adhesion of printed structures. For this reason, the investigation…

1714

Abstract

Purpose

This paper aims to find an optimal surface treatment of commonly used polymeric substrates for achieve the high adhesion of printed structures. For this reason, the investigation of substrates surfaces from different perspectives is presented in this paper.

Design/methodology/approach

The contact angle measurements as well as the roughness measurements were realised for the analysis of surface properties of investigated substrates. The impact of applied chemical agents for surface treatment onto the wettability is analysed for polyimide, polyethylene terephthalate and polyethylene naphthalene substrates.

Findings

The results prove the correlation among wettability, surface energy and work of adhesion with respect to the theoretical background. The surface treatment of polymeric substrates by chemical agents, such as acetone, toluene, ethanol, isopropyl and fluor silane polymer, has a significant impact onto the wettability of substrates which affects the final deposition process of nanoinks.

Originality/value

The main benefit of the surfaces’ investigation presented in this paper lays in surface modification by readily available chemical agents for optimising the deposition process nanoinks used in inkjet printing technology.

Details

Circuit World, vol. 42 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

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