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Article
Publication date: 20 September 2022

Ashok Kumar L. and Kumaravel R.

The purpose of this paper is to check the Solar Photovoltaic (PV) inverter working condition with modified unipolar switching pulse. The gate pulse for the inverter switches is…

Abstract

Purpose

The purpose of this paper is to check the Solar Photovoltaic (PV) inverter working condition with modified unipolar switching pulse. The gate pulse for the inverter switches is generated in MATLAB simulation and interfaced with hardware protype. Simulation results can be compared with hardware results.

Design/methodology/approach

A considerable amount of research has been done on different Pulse Width Modulation (PWM) techniques. Based on the findings, a modified Unipolar Sinusoidal PWM technique was created with one reference signal and two carrier signals+ (one for the positive half cycle and the other for the negative half cycle) and simulated in the MATLAB/Simulink platform. The prototype inverter module receives the simulated switching pulses via dSPACE DS1104 hardware software interfacing board. The hardware implementation has been done, and the hardware results compared with simulation results for various input voltage levels using resistive load.

Findings

This modified switching pulse has dead band and additional hardware setup is not required. 3-phase multi-level inverter output waveform has been achieved with six switches in this method and with low filter values, pure sine wave output can be obtained in simulation. By this method of switching pulse generation and testing, for every modification in switching pulse hardware gate driver is not required. Resulting time consumption and money investment are lower.

Originality/value

Modified Unipolar SPWM pulse generation technique is novel method for solar PV inverter. The switching pulse has been designed and tested in both MATLAB/Simulation and hardware prototype inverter. Hardware and software results are identical. This method of pulse generation and hardware implementation has not been done anywhere before.

Details

Circuit World, vol. 49 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Open Access
Article
Publication date: 24 May 2022

Priyam Ghosh, Mothilal Lakavath, Karthikeyan Somaskandan and Satyanarayana Parayitam

This paper aims to investigate the relationship between general attitude toward advertising and consumers' purchase intention. The relationship between cognitive attitude…

1517

Abstract

Purpose

This paper aims to investigate the relationship between general attitude toward advertising and consumers' purchase intention. The relationship between cognitive attitude, intrusiveness attitude, evaluative judgments, affective response and general attitude toward ad was examined. Furthermore, reliability as a moderator in the relationship between cognitive attitude, intrusiveness attitude, evaluative judgments, and affective response and the general attitude toward ad were studied.

Design/methodology/approach

Data from women consumers who subscribe to fashion magazines in India were collected and analyzed using a structured survey instrument. Women were selected because the products were related to women, including facial and body-care products, women sportswear, shampoos, lipstick, handbags, etc. Unit of analysis in this research is “observations,” and in all, 400 data points were analyzed, and to test hypothesized relationships, hierarchical regression and logistic regression were employed.

Findings

A conceptual model is developed and tested where (1) cognitive attitude toward ad, intrusiveness, evaluative judgments and affective responses are related to general attitude toward ad, and (2) general attitude toward ad is related to purchase intention. The hierarchical regression results show that (1) reliability moderates the relationship between cognitive attitude, intrusiveness, affective responses and general attitude toward ad. The logistic regression results support the positive relationship between general attitude toward ad and purchase intention.

Research limitations/implications

Since the present research is based on self-report measures, the limitations of social desirability bias and common method bias are inherent. Second, this research focuses only on women consumers and products purchased by women. The research has implications for literature on advertising, especially women-related products.

Practical implications

This study contributes to practicing managers who are interested in promoting the women-related products. This study highlights the importance of general attitude toward ad as a precursor for consumers purchase intention. The study provides justification for enormous amounts of money invested in fashion advertising because of their effects on consumer behavior.

Originality/value

This study provides new insights about the effects reliability on general attitude toward ad and consumers' purchase intention. The conceptual model developed in this study adds novelty by considering reliability as a moderator, in addition to the direct relationships which have been studied by earlier researchers.

Details

South Asian Journal of Marketing, vol. 3 no. 2
Type: Research Article
ISSN: 2719-2377

Keywords

Article
Publication date: 3 November 2022

Leilei Fan, Zhilin Sun, Wuyi Wan and Yunze Shen

To modify a conventional evacuated tube, an improved asymmetric U-type evacuated tube (AUET) is proposed. This study aims to investigate the thermal and hydrodynamic performances…

Abstract

Purpose

To modify a conventional evacuated tube, an improved asymmetric U-type evacuated tube (AUET) is proposed. This study aims to investigate the thermal and hydrodynamic performances of a modified tube and determine the optimal structural form.

Design/methodology/approach

Based on the variation of fluid proprieties with temperature, the formulated numerical model was validated and then deployed to investigate the natural circulation in the evacuated tubes. A dimensionless number was proposed to quantify the stratification effect. The influence of the degree of asymmetry of U-type evacuated tubes on the flow patterns, mass flow rate, temperature distribution, thermal stratification and energy conversion efficiency was studied.

Findings

When the degree of asymmetry is large, a higher velocity and better thermal stratification are achieved, thereby avoiding stagnant water at the bottom of the tubes simultaneously. Compared with the conventional evacuated tube, the improved evacuated tube exhibited a higher thermal efficiency.

Originality/value

The originally proposed AUET was proven to have better performance in avoiding stagnant water, reducing fluid mixing and improving the heat transfer efficiency.

Article
Publication date: 1 April 2007

A. Kumaravel, N. Ganesan and Raju Sethuraman

The paper deals with the investigation of linear buckling and free vibration behavior of layered and multiphase magneto‐electro‐elastic (MEE) beam under thermal environment. The…

Abstract

The paper deals with the investigation of linear buckling and free vibration behavior of layered and multiphase magneto‐electro‐elastic (MEE) beam under thermal environment. The constitutive equations of magneto‐electro‐elastic materials are used to derive finite element equations involving the coupling between mechanical, electrical and magnetic fields. The finite element model has been verified with the commercial finite element package ANSYS. The influence of magneto electric coupling on critical buckling temperature is investigated between layered and multiphase magneto‐electro‐elastic beam. Furthermore, the influence of temperature rise on natural frequencies of magneto‐electro‐elastic beam with layered and different volume fraction is presented.

Details

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

Keywords

Article
Publication date: 30 November 2023

Dong Chen, Rui Zhang and JiaCheng Jiang

This study aims to investigate the morphology and physicochemical properties of BiOBr/Polyvinylidene fluoride (PVDF) composite membranes and the differences in the properties of…

Abstract

Purpose

This study aims to investigate the morphology and physicochemical properties of BiOBr/Polyvinylidene fluoride (PVDF) composite membranes and the differences in the properties of BiOBr/PVDF composite membranes made by adding different precursor ratios during the casting process.

Design/methodology/approach

In this paper, sodium bromide and Bi(NO3)3 were used as precursors for the preparation of BiOBr photocatalysts, and PVDF membranes were modified by using the phase conversion method in conjunction with the in situ deposition method to produce BiOBr/PVDF hydrophilic composite membranes with both membrane separation and photocatalytic capabilities.

Findings

The characterization results confirmed that the composites were successfully and homogeneously co-mingled in the PVDF membranes. The related performance of the composite membrane was tested, and it was found that the composite membrane with the optimal precursor incorporation ratio had good photocatalytic efficiency and antipollution ability; the removal efficiencies of methyl orange, rhodamine B and methylene blue were 80.43%, 85.02% and 86.94%, respectively, in 2.5 h. The photocatalytic efficiency of composite membranes with different precursor ratios increased and then decreased with the increase of the precursor addition ratio.

Originality/value

The composite membrane is prepared by phase conversion method with in situ deposition method, and the BiOBr material has unique advantages for the degradation of organic dyes. The comprehensive experimental data can be known that the composite membrane prepared in this paper has high degradation efficiency and good durability for organic dyes.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 12 November 2010

A. Kumaravel, N. Ganesan and Raju Sethuraman

The purpose of the paper is to investigate the linear thermal buckling and vibration analysis of layered and multiphase magneto‐electro‐elastic (MEE) cylinders made of…

Abstract

Purpose

The purpose of the paper is to investigate the linear thermal buckling and vibration analysis of layered and multiphase magneto‐electro‐elastic (MEE) cylinders made of piezoelectric/piezomagnetic materials using finite element method.

Design/methodology/approach

The constitutive equations of MEE materials are used to derive the finite element equations involving the coupling between mechanical, electrical, magnetic and thermal fields. The present study is limited to clamped‐clamped boundary conditions. The linear thermal buckling is carried out for an axisymmetric cylinder operating in a steady state axisymmetric uniform temperature rise. The influence of stacking sequences and volume fraction of multiphase MEE materials on critical buckling temperature and vibration behaviour is investigated. The influence of coupling effects on critical buckling temperature and vibration behaviour is also studied.

Findings

The critical buckling temperature is higher for MEE axisymmetric cylinder as compared to elastic cylinder.

Originality/value

Linear thermal buckling and vibration analysis of MEE axisymmetric cylinders are studied using the finite element approach. The structure can be used for active vibration control, sensors and actuators. Studying the buckling and vibration behaviour of such structures and influence of coupling effect is extremely useful for the design of magnetoelectroelastic structures.

Details

Multidiscipline Modeling in Materials and Structures, vol. 6 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Open Access
Article
Publication date: 3 February 2018

M. Sudha and A. Kumaravel

Rough set theory is a simple and potential methodology in extracting and minimizing rules from decision tables. Its concepts are core, reduct and discovering knowledge in the form…

Abstract

Rough set theory is a simple and potential methodology in extracting and minimizing rules from decision tables. Its concepts are core, reduct and discovering knowledge in the form of rules. The decision rules explain the decision state to predict and support the new situation. Initially it was proposed as a useful tool for analysis of decision states. This approach produces a set of decision rules involves two types namely certain and possible rules based on approximation. The prediction may highly be affected if the data size varies in larger numbers. Application of Rough set theory towards this direction has not been considered yet. Hence the main objective of this paper is to study the influence of data size and the number of rules generated by rough set methods. The performance of these methods is presented through the metric like accuracy and quality of classification. The results obtained show the range of performance and first of its kind in current research trend.

Details

Applied Computing and Informatics, vol. 16 no. 1/2
Type: Research Article
ISSN: 2634-1964

Keywords

Article
Publication date: 3 January 2017

Thanapackiam P., Kumaravel Mallaiya, Rameshkumar S. and Subramanian S.S.

This paper aims to evaluate the inhibition efficiency of norfloxacin on the corrosion of copper in 1.0 M nitric acid and 0.5 M sulfuric acid solutions.

Abstract

Purpose

This paper aims to evaluate the inhibition efficiency of norfloxacin on the corrosion of copper in 1.0 M nitric acid and 0.5 M sulfuric acid solutions.

Design/methodology/approach

Evaluation was carried out by electrochemical techniques such as electrochemical impedance spectroscopy and potentiodynamic polarization studies. Scanning electron microscopy was used, and it finally confirmed the existence of the adsorbed film.

Findings

The electrochemical measurements showed that norfloxacin has good inhibition efficiency on the corrosion of copper in 1.0 M nitric acid and 0.5 M sulfuric acid solutions. The inhibition action of norfloxacin in both of the corrosive media was observed to be of mixed type but with more of cathodic nature. The temperature dependence of the corrosion rate was studied in the temperature range from 35 to 55°C and the activation energy (Ea) was calculated. The adsorption of norfloxacin molecules on copper surface obeyed Langmuir adsorption isotherm. Studies on the potential of zero charge have been carried out to establish the mechanism of adsorption of the inhibitor onto the metal surface. The thermodynamic parameters such as the adsorption equilibrium constant (Kads) and the free energy of adsorption (ΔGads) were calculated. The value of free energy of adsorption very close to −40 kJmol−1 indicates that the adsorption is through electrostatic coulombic attraction and chemisorption. The decrease in value of Ea with the addition of inhibitor also shows the chemisorption of the inhibitor on the metal surface.

Originality/value

This paper indicates that norfloxacin can act as a good inhibitor for the corrosion of copper in both the acid media.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 February 2021

R. Srilakshmi and Jayabhaskar Muthukuru

The mischievous nodes that defy the standard corrupt the exhibition of good nodes considerably. Therefore, an intrusion discovery mechanism should be included to the mobile ad-hoc…

65

Abstract

Purpose

The mischievous nodes that defy the standard corrupt the exhibition of good nodes considerably. Therefore, an intrusion discovery mechanism should be included to the mobile ad-hoc network (MANET). In this paper, worm-hole and other destructive malignant attacks are propelled in MANET.

Design/methodology/approach

A wireless ad-hoc network also called as mobile ad-hoc network (MANET) is a gathering of hubs that utilizes a wireless channel to exchange information and coordinate together to establish information exchange among any pair of hubs, without any centralized structure. The security issue is a major difficulty while employing MANETs.

Findings

Consequently, the attacks due to the malicious node activity are detected using Hybrid Reactive Search and Bat (HRSB) mechanism to prevent the mischievous nodes from entering the network beneath the untruthful information. Moreover, the attack detection rate and node energy are predicted for determining the lifetime of the node.

Originality/value

The simulation outcomes of the proposed HRSB technique are evaluated with the prevailing methods. The comparison studies have proven the efficacy of the current research model by attaining high attack detection rate and achieving more network lifetime.

Details

International Journal of Intelligent Unmanned Systems, vol. 10 no. 1
Type: Research Article
ISSN: 2049-6427

Keywords

Article
Publication date: 8 May 2018

Nagarajan Karthiyayini, C. Rajendran and Munusamy Kumaravel

The purpose of this paper is to formulate the strategy for improving the laboratory practices to enhance customer satisfaction by analyzing the performance of critical factors of…

Abstract

Purpose

The purpose of this paper is to formulate the strategy for improving the laboratory practices to enhance customer satisfaction by analyzing the performance of critical factors of IS/ISO/IEC 17025 (2005) laboratory accreditation and the importance attached by the quality/technical managers in the accredited Indian testing/calibration laboratories.

Design/methodology/approach

The perceptions of the critical factors of laboratory accreditation and the importance attached by the quality/technical managers in their organizations have been collected and analyzed to develop an importance-performance analysis (IPA) model to enhance the customer satisfaction.

Findings

Findings report that the performance of the critical factors and the importance assigned to them are not the same. There exist gaps between the performance and importance which need to be measured and analyzed by the management to strive toward continual improvement to enhance the customer satisfaction through the accredited testing and calibration services.

Research limitations/implications

This study is restricted to 54 responses out of 150 which were sent (i.e. about 36 percent response rate) to capture the perspectives of the quality/technical managers.

Practical implications

This study would enable the accredited laboratories to analyze the gap in performance and the importance assigned to critical factors through the feedback from the quality/technical managers. By analyzing the strengths and weaknesses in the accredited testing/calibration laboratories, managerial decisions and strategic plans can be proposed to gain greater insights into benchmarking improvement of the laboratory quality management system with the existing resources to strive toward customer satisfaction.

Originality/value

This paper proposes IPA as a tool to assess the gap between the importance and performance of critical factors of accredited testing and calibration laboratories in India.

Details

Benchmarking: An International Journal, vol. 25 no. 4
Type: Research Article
ISSN: 1463-5771

Keywords

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