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Article
Publication date: 20 June 2020

Fossy Mary Chacko, Ginu Ann George, Jayan M.V. and Prince A.

This paper aims to propose an improved multifunctional control strategy for achieving real, reactive power flow control and the mitigation of power quality issues in grid…

104

Abstract

Purpose

This paper aims to propose an improved multifunctional control strategy for achieving real, reactive power flow control and the mitigation of power quality issues in grid integrated photovoltaic (GIPV) systems.

Design/methodology/approach

The paper proposes a dual stage, three phase, multifunctional GIPV system with modified instantaneous reactive power (IRP) theory-based and modified synchronous reference frame (SRF) theory-based control algorithms for reference template generation with continuous load power requirement tracking. The control structure is designed so as to impart virtual distribution static compensator functionality to the photovoltaic inverter. The dual mode operation in active filter and renewable power injection modes provides enhanced capability to the GIPV system. A comprehensive evaluation of the dynamic behaviour of the GIPV system is carried out for various conditions of irradiance and load under MATLAB/Simulink platform. The performance comparison is done considering an uncompensated system and the GIPV system with both proposed control algorithms.

Findings

The extensive simulation results demonstrate that the proposed modified SRF theory-based multifunctional control strategy shows superior performance in real and reactive power flow control; reduction in real and reactive burden of the utility grid; and regulation of dc bus voltage under varying scenarios of irradiance and load. Furthermore, there is improvement of grid power factor and reduction in total harmonic distortion of grid currents in compliance with the IEEE 519 standard even with highly non-linear loads at the point of common coupling.

Originality/value

The proposed modified SRF theory-based multifunctional controller offers a viable solution for power quality enhancement as well as the realization of effective real and reactive power flow control in GIPV systems. Thus, the penetration level of distributed generation can be increased in this era of global energy crisis.

Details

World Journal of Engineering, vol. 17 no. 4
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 1 April 1991

V. Jayan and P.R. Vaya

SEM picture of rectangular gratings realised by chemical etching mostly resembled a triangular grating. Symmetric triangular gratings can give better directionality to the DFB…

51

Abstract

SEM picture of rectangular gratings realised by chemical etching mostly resembled a triangular grating. Symmetric triangular gratings can give better directionality to the DFB laser beam. In this communication,the optimal Bragg order,grating period and tooth height,active layer thickness were presented from a study of the optical power coupling for a symmetric triangular GaAs‐AlGaAs structure. The numerical parameters so obtained were compared to the reported results and found that chemically etched rectangular grating obeys the theory of symmetric triangular grating with remarkable accuracy.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 10 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 30 December 2022

Subbarama Kousik Suraparaju, Arjun Singh K., Vijesh Jayan and Sendhil Kumar Natarajan

The utilisation of renewable energy sources for generating electricity and potable water is one of the most sustainable approaches in the current scenario. Therefore, the current…

86

Abstract

Purpose

The utilisation of renewable energy sources for generating electricity and potable water is one of the most sustainable approaches in the current scenario. Therefore, the current research aims to design and develop a novel co-generation system to address the electricity and potable water needs of rural areas.

Design/methodology/approach

The cogeneration system mainly consists of a solar parabolic dish concentrator (SPDC) system with a concentrated photo-voltaic module at the receiver for electricity generation. It is further integrated with a low-temperature thermal desalination (LTTD) system for generating potable water. Also, a novel corn cob filtration system is introduced for the pre-treatment to reduce the salt content in seawater before circulating it into the receiver of the SPDC system. The designed novel co-generation system has been numerically and experimentally tested to analyse the performance at Karaikal, U.T. of Puducherry, India.

Findings

Because of the pre-treatment with a corn cob, the scale formation in the pipes of the SPDC system is significantly reduced, which enhances the efficiency of the system. It is observed that the conductivity, pH and TDS of seawater are reduced significantly after the pre-treatment by the corncob filtration system. Also, the integrated system is capable of generating 6–8 litres of potable water per day.

Originality/value

The integration of the corncob filtration system reduced the scaling formation compared to the general circulation of water in the hoses. Also, the integrated SPDC and LTTD systems are comparatively economical to generate higher yields of clean water than solar stills.

Details

World Journal of Engineering, vol. 21 no. 2
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 20 November 2020

Rajendran Selvamani, M. Mahaveer Sree Jayan and Farzad Ebrahimi

The purpose of this paper is concerned with the study of nonlinear ultrasonic waves in a magneto-flexo-thermo (MFT) elastic armchair single-walled carbon nanotube (ASWCNT) resting…

88

Abstract

Purpose

The purpose of this paper is concerned with the study of nonlinear ultrasonic waves in a magneto-flexo-thermo (MFT) elastic armchair single-walled carbon nanotube (ASWCNT) resting on polymer matrix.

Design/methodology/approach

A mathematical model is developed for the analytical study of nonlinear ultrasonic waves in a MFT elastic armchair single walled carbon nanotube rested on polymer matrix using Euler beam theory. The analytical formulation is developed based on Eringen’s nonlocal elasticity theory to account small scale effect. After developing the formal solution of the mathematical model consisting of partial differential equations, the frequency equations have been analysed numerically by using the nonlinear foundations supported by Winkler-Pasternak model. The solution is obtained by ultrasonic wave dispersion relations.

Findings

From the literature survey, it is evident that the analytical formulation of nonlinear ultrasonic waves in an MFT elastic ASWCNT embedded on polymer matrix is not discussed by any researchers. So, in this paper the analytical solutions of nonlinear ultrasonic waves in an MFT elastic ASWCNT embedded on polymer matrix are studied. Parametric studies is carried out to scrutinize the influence of the nonlocal scaling, magneto-electro-mechanical loadings, foundation parameters, various boundary condition and length on the dimensionless frequency of nanotube. It is noticed that the boundary conditions, nonlocal parameter and tube geometrical parameters have significant effects on dimensionless frequency of nanotubes.

Originality/value

This paper contributes the analytical model to find the solution of nonlinear ultrasonic waves in an MFT elastic ASWCNT embedded on polymer matrix. It is observed that the increase in the foundation constants raises the stiffness of the medium and the structure is able to attain higher frequency once the edge condition is C-C followed by S-S. Further, it is noticed that the natural frequency is arrived below 1% in both local and nonlocal boundary conditions in the presence of temperature coefficients. Also, it is found that the density and Poisson ratio variation affects the natural frequency with below 2%. The results presented in this study can provide mechanism for the study and design of the nano devices such as component of nano oscillators, micro wave absorbing, nano-electron technology and nano-electro--magneto-mechanical systems that make use of the wave propagation properties of ASWCNTs embedded on polymer matrix.

Details

World Journal of Engineering, vol. 18 no. 1
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 13 March 2017

Adel Alferaih

The purpose of this paper is to develop and present a research model on various emotional intelligence (EI) constructs which have been found to influence job performance in the…

1547

Abstract

Purpose

The purpose of this paper is to develop and present a research model on various emotional intelligence (EI) constructs which have been found to influence job performance in the prior literature.

Design/methodology/approach

In addition to leadership and EI, the constructs are clustered under different categories: self-awareness includes self-confidence, emotional self-awareness and accurate self-assessment; self-management includes self-control, adaptability, conscientiousness, trustworthiness and optimism; social awareness includes empathy, organizational awareness and service orientation; and social skills groups’ communication, change catalyst, developing others and self-monitoring.

Findings

The paper proposes 17 hypotheses concerning significant relationships between these constructs and job performance.

Originality/value

The paper proposes a new approach toward studying the impact of various constructs of EI on job performance in Saudi banking sector.

Details

International Journal of Organizational Analysis, vol. 25 no. 1
Type: Research Article
ISSN: 1934-8835

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Article
Publication date: 24 November 2021

Divya V., Divya Jayan and Asoka Kumar

As there is a strong inducement to develop new colored inorganic materials to substitute the current industrial pigments that are based on toxic metals hazardous to health and the…

119

Abstract

Purpose

As there is a strong inducement to develop new colored inorganic materials to substitute the current industrial pigments that are based on toxic metals hazardous to health and the environment, the purpose of this paper is to invent environmentally benign rare earth-based colorants as viable alternatives to the traditional toxic pigment formulations. Herein, the authors developed a series of rare earth pigments having the general formula Ca0.1 Ln0.9 PO4 ( Ln = Y , Pr , mixed rare earth oxides, RE and Di). After studying all the optical properties, the authors have gone for some coloring application in plastic like PMMA.

Design/methodology/approach

The designed pigments were synthesized by traditional solid-state method. Stoichiometric amounts of each reagent were mixed in an agate mortar and the mixtures were calcined at optimized temperature 1000 °C for 4 h in electric furnace followed by auto–cooling. The samples were characterized by X-ray diffraction diffraction, UV–vis spectroscopy, scanning electron microscope (SEM), particle size distribution, color coordinates determination, acid/alkali test, thermo gravimetric (TG) analysis and CIE–1976 L*a*b* color scales. Among the various lanthanide ions and calcium ion as dopant, the pigment composition shows various hues ranges from green to yellow. The designed pigments consist of non–toxic elements and were further found to possess high thermal and chemical stability. The pigments were also found to be appropriate candidates for the coloration of polymer substrates like PMMA.

Findings

The present investigations establish that various color hues can be achieved by the incorporation of suitable chromophore metal ions like calcium in various rare earth host lattice by tuning of the band gaps. The coloring mechanism is based on the strong absorption of the pigments in the blue and red regions due to electronic transitions of the micro states of rare earth ion. The pigment composition shows various hues ranges from green to yellow. The coloring mechanism is based on the tuning of band gap by the dopant like calcium in various rare earth host lattice. In addition, this pigment was chemically and thermally stable. Finally, it has applied in plastics like PMMA.

Research limitations/implications

Mechanism of the color appearance using band calculations and on possible applications of rare earth phosphate powders as pigments in plastics and paints have not been explored much. However, the properties of the Ca-doped rare earth phosphate implies that this material has a potential to be applied as a satisfactory pigment for coating or coloring except for glaze, which may cause a side reaction at high temperatures, especially taking into consideration the economics and ecologies. The possibility of Ca2+ incorporation in CePO4 with monazite structure-type has been established.

Practical implications

The designed pigments consist of non-toxic elements and were further found to possess high thermal and chemical stability. The pigments were also found to be appropriate candidates for the coloration of polymer substrates. Thus, the present environmental friendly pigment powders may find potential alternative to the classical toxic inorganic pigments for various applications.

Social implications

There is a strong incentive to design new colorants based on inorganic materials to substitute for industrial pigments that are based on heavy elements hazardous to health and the environment. However, several industrial yellow pigments such as cadmium yellow (CdS), chrome yellow (PbCrO4) and nickel titanium yellow (TiO2-NiO-Sb2O3) contain the harmful elements (e.g. Cd, Pb, Cr and Sb) for the human body as well as the environment. The designed pigments consist of non-toxic elements and were further found to possess high thermal and chemical stability. The pigments were also found to be appropriate candidates for the coloration of polymer substrates. Thus, the present environmental friendly pigment powders may find potential alternative to the classical toxic inorganic pigments for various applications.

Originality/value

There is a strong incentive to design new colorants based on inorganic materials to substitute for industrial pigments that are based on heavy elements hazardous to health and the environment. However, several industrial yellow pigments such as cadmium yellow (CdS), chrome yellow (PbCrO4) and nickel titanium yellow (TiO2-NiO-Sb2O3) contain the harmful elements (e.g. Cd, Pb, Cr and Sb) for the human body as well as the environment. So, the authors have developed new class of inorganic pigments that are both non-toxic and environmentally unimpeachable, while preserving or even exceeding the optical, thermal and chemical characteristics of the existing commercial pigments. The developed colorants find practical applications in polymer matrix like PMMA.

Details

Pigment & Resin Technology, vol. 52 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 14 August 2017

Jayan Chirayath Kurian and Blooma Mohan John

The purpose of this paper is to explore themes eventuating from the user-generated content posted by users on the Facebook page of an emergency management agency.

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Abstract

Purpose

The purpose of this paper is to explore themes eventuating from the user-generated content posted by users on the Facebook page of an emergency management agency.

Design/methodology/approach

An information classification framework was used to classify user-generated content posted by users including all of the content posted during a six month period (January to June 2015). The posts were read and analysed thematically to determine the overarching themes evident across the entire collection of user posts.

Findings

The results of the analysis demonstrate that the key themes that eventuate from the user-generated content posted are “Self-preparedness”, “Emergency signalling solutions”, “Unsurpassable companion”, “Aftermath of an emergency”, and “Gratitude towards emergency management staff”. Major user-generated content identified among these themes are status-update, criticism, recommendation, and request.

Research limitations/implications

This study contributes to theory on the development of key themes from user-generated content posted by users on a public social networking site. An analysis of user-generated content identified in this study implies that, Facebook is primarily used for information dissemination, coordination and collaboration, and information seeking in the context of emergency management. Users may gain the benefits of identity construction and social provisions, whereas social conflict is a potential detrimental implication. Other user costs include lack of social support by stakeholders, investment in social infrastructure and additional work force required to alleviate the technological, organisational, and social barriers in communication among stakeholders in emergency management. A collective activity system built upon the Activity Theory was used as a lens to describe users’ activity of posting content on the Facebook page of an emergency management agency.

Practical implications

By analysing the findings, administrators and policy makers of emergency management could identify the extent to which the core principles of disaster recovery are accomplished using public social networking sites. These are achieved in relation to: pre-disaster recovery planning; partnership and inclusiveness; public information messaging; unity of effort; and, psychological recovery to maximise the success of recovery in a disaster. Furthermore, a core principle which evoked a mixed response was timeliness and flexibility.

Originality/value

Previous studies have examined the role of social networking sites in disastrous situations, but to date there has been very little research into determining themes found in user-generated content posted on the Facebook page of an emergency management agency. Hence, this study addresses the gap in literature by conducting a thematic analysis of user-generated content posted on the Facebook page of the Federal Emergency Management Agency.

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Article
Publication date: 1 April 1984

Roy Davies and Brian James

Librarians have sought to reduce the cost of cataloguing by sharing bibliographic data, but it is still an expensive, labour intensive process which is a reason why short entry…

287

Abstract

Librarians have sought to reduce the cost of cataloguing by sharing bibliographic data, but it is still an expensive, labour intensive process which is a reason why short entry catalogues have been advocated. Existing computer systems have tended to automate the clerical aspects of cataloguing but developments in artificial intelligence hold out the prospect of automating the professional aspects too. The feasibility of creating an expert system for cataloguing using the PROLOG programming language, was the subject of a postgraduate research project at Exeter University. Such a system would be capable of applying many AACR2 cataloguing rules automatically and would also cope with rules governing local practices.

Details

Program, vol. 18 no. 4
Type: Research Article
ISSN: 0033-0337

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Article
Publication date: 17 November 2020

Jayan Chirayath Kurian, Dion Hoe-Lian Goh and Blooma Mohan John

The purpose of this study is to identify organizational cultural factors and overarching themes on emergency management evident across the Facebook page of an emergency management…

676

Abstract

Purpose

The purpose of this study is to identify organizational cultural factors and overarching themes on emergency management evident across the Facebook page of an emergency management organization. This study also aims to understand the dimensions of social capital that influence the reputation of emergency management organization using the lens of organizational culture.

Design/methodology/approach

The organizational cultural factors defined in the literature were used to classify content posted by the organization during a six-month period. The posts were read and analyzed thematically to determine the overarching themes evident across the collected posts. The dimensions of social capital defined in the literature were used to determine its influence on the reputation of an emergency management organization.

Findings

The organizational cultural factors that emerged from the analysis are openness and future orientation without any evidence on risk-taking and flexibility. An analysis of cultural factors indicates that organizational culture facilitates knowledge exchange and knowledge combination. The key themes embedded in the organization's posts are emergency preparedness, communication devices for emergency management, coordination and admiration. The dimensions of social capital that influenced the reputation of emergency management organization were group characteristics, volunteerism, generalized norms and togetherness. Though previous studies have found the influence of culture on social capital, this study extends those findings by identifying the dimensions of culture (i.e. openness and future orientation) that reflects the social capital dimensions (i.e. generalized norms and group characteristics) in an organizational setting.

Research limitations/implications

This study contributes to theory on the identification of cultural factors from content posted by emergency management organizations on a public social networking site (SNS). The organization benefited in terms of its reputation through the dimensions of social capital which are group characteristics, volunteerism, generalized norms and togetherness. One of the organizational reputation dimensions that was evident in this study was moral reputation which is a contribution of this study.

Practical implications

Among the guiding principles of Sendai Framework for Disaster Risk Reduction, three guiding principles were evident in the posts of the emergency management organization. These principles which represent the practical implications of this study are disaster risk reduction through cooperation, inclusiveness of minority community members and implementing cost-effective and sustainable development policies for future through investment.

Originality/value

Previous studies have examined organizational culture in general, but to date there has been very little research into determining cultural factors that facilitate knowledge exchange and knowledge combination. This is also a unique study which identified the dimensions of social capital and organizational reputation in emergency management.

Details

Online Information Review, vol. 45 no. 2
Type: Research Article
ISSN: 1468-4527

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Article
Publication date: 9 November 2015

Jayan Chirayath Kurian

– The purpose of this paper is to explore the type and implications of user-generated content posted by users of an open access institutional repository (DSpace) on Facebook.

1140

Abstract

Purpose

The purpose of this paper is to explore the type and implications of user-generated content posted by users of an open access institutional repository (DSpace) on Facebook.

Design/methodology/approach

The identified user-generated content was organised into three categories: personal; professional; and social information. It encompassed all content from the members of the “DSpace” Facebook group, posted during the seven-year period (2007-2014). The posts were read and analysed to identify and categorise user-generated content posted by users to determine how Facebook is used by open access repository users.

Findings

The results of analysis demonstrate the importance of social information posted by users over personal and professional information. Major types of user-generated content posted by users in the social information category were request, greetings, status-update, and announcement. Further, there has been a threefold increase in the number of user postings in the last two years (2013-2014), when posts were analysed over a seven-year period.

Research limitations/implications

This study contributes to the theory on the implications eventuating from user-generated content posted by users of an open access institutional repository. An analysis of user-generated content identified in this study implies that users of DSpace open access repository are primarily using Facebook for information seeking, relationship building, and knowledge dissemination.

Practical implications

By analysing the findings, administrators and policy makers of open access repositories could identify the extent of user support in the form of technical assistance, improved sustainability of supported projects, user community development, marketing and communications required to sustain open access scholarly communication.

Originality/value

Previous studies examined how social networking sites have been used for a different purpose (interaction, collaboration, and discussion), but to date there has been very little research into the use of Facebook, a public social networking site, by open access repository users. Hence, this study addresses this gap in the literature by an interpretive analysis of user-generated content posted by users on the “DSpace” Facebook group.

Details

Online Information Review, vol. 39 no. 7
Type: Research Article
ISSN: 1468-4527

Keywords

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