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1 – 10 of 13H.R. Evans, D.O. Peksa and A.R. Taherian
The paper reviews the application of the finite element method to the analysis of large‐deflection elasto‐plastic behaviour and traces the development of such a solution…
Abstract
The paper reviews the application of the finite element method to the analysis of large‐deflection elasto‐plastic behaviour and traces the development of such a solution for plated structures. The accuracy of the approach is established by many comparisons with available solutions for isolated plates and conclusions are drawn on suitable idealizations for plated structures. The results of an analysis of a typical plate girder, allowing fully for the interaction between the component plates, are presented. Comparisons with experimentally measured values for the girder confirm the validity of the proposed approach for the study of the collapse modes of plated structures. The need for expensive experimentation is thereby reduced.
Fupeng Cheng, Jinglong Cui, Shuai Xu, Hongyu Wang, Pengchao Zhang and Juncai Sun
The purpose of this paper is to improve the surface electrical conductivity and corrosion resistance of AISI 430 stainless steel (430 SS) as bipolar plates for proton…
Abstract
Purpose
The purpose of this paper is to improve the surface electrical conductivity and corrosion resistance of AISI 430 stainless steel (430 SS) as bipolar plates for proton exchange membrane fuel cells (PEMFCs), a protective Nb-modified layer is formed onto stainless steel via the plasma surface diffusion alloying method. The effect of diffusion alloying time on electrochemical behavior and surface conductivity is evaluated.
Design/methodology/approach
In this work, the surface electrical conductivity and corrosion resistance of modified specimen are evaluated by the potentiodynamic and potentionstatic polarization tests. Moreover, the hydrophobicity is also investigated by contact angle measurement.
Findings
The Nb-modified 430 SS treated by 1.5 h (1.5Nb) presented a lower passivation current density, lower interfacial contact resistance and a higher hydrophobicity than other modified specimens. Moreover, the 1.5 Nb specimen presents a smoother surface than other modified specimens after potentionstatic polarization tests.
Originality/value
The effect of diffusion alloying time on electrochemical behavior, surface conductivity and hydrophobicity of modified specimen is evaluated. The probable anti-corrosion mechanism of Nb-modified specimen in simulated acid PEMFC cathode environment is presented.
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The inclusion of natural antioxidants and nanoparticles into edible coatings can improve their structure, functionality and applicability in foods. This study aims to…
Abstract
Purpose
The inclusion of natural antioxidants and nanoparticles into edible coatings can improve their structure, functionality and applicability in foods. This study aims to determine the antibacterial effect of new nano-composite based on bean pod shell gum (BPSG), silver nanoparticle (SNP) and herbal essential oil (EO).
Design/methodology/approach
For this purpose, BPSG (4 per cent w/v), SNP (0.5-1 per cent w/v) and Helichrysum arenarium EO (1-2 per cent v/v) were mixed. After preparation the edible film, the antibacterial activity was tested on five food-borne pathogenic bacteria in two categories including two-gram positives and three-gram negatives bacteria. The EO composition was determined by GC–mass spectrometry and the antibacterial activity was tested using disk diffusion test.
Findings
Results showed that gram-positive bacteria were more susceptible than gram-negative bacteria. Increasing Helichrysum arenarium EO and SNP content increased antimicrobial activity of the edible film based on BPSG, so that the treatment containing 2 per cent v/v Helichrysum arenarium EO and 1 per cent w/v SNP led to the highest inhibition zone (8.1-13.1 mm) compared to treatment containing 1 per cent v/v Helichrysum arenarium EO and 0.5 per cent w/v SNP with inhibition zone range of 5.4-9.9 mm and the difference was statistically significant (p = 0.41). Also, the chemical composition analysis of the EO identified a total of 38 compounds in which a-pinene (32 per cent), 1,8-cineole (16 per cent), α-humulene (15 per cent) and ß-caryophyllene (8 per cent) were the main fractions. Other separated components accounted less than 29 per cent of the oil.
Originality/value
In general, SNP and Helichrysum arenarium EO improved the functional properties including the antimicrobial activity of the edible film based on BPSG, which increases the potential to be used as active packaging for fresh products.
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Jamilah Al-Muhammady Mohammad, Ahmad Fuad Abdul Rahim, Mohd Zarawi Mat Nor, Rozaziana Ahmad and Muhamad Saiful Bahri Yusoff
The purpose of this paper is to evaluate mentoring behaviours in a public medical school in Malaysia and examine factors associated with those mentoring behaviours. The…
Abstract
Purpose
The purpose of this paper is to evaluate mentoring behaviours in a public medical school in Malaysia and examine factors associated with those mentoring behaviours. The study is important because effective mentoring promotes the personal and professional growth of mentees.
Design/methodology/approach
A cross-sectional study was conducted with a population of 632 medical students. The authors used the Mentor Behaviour Scale (MBS) to measure four domains of mentoring behaviour: mentoring relationship structure, engagement, autonomy support and competency support. The authors evaluated the scoring of these domains as high, moderate or low scores.
Findings
A total of 508 (80.4 per cent) medical students in Years 2–5 participated in this study. Mentoring relationship structure, engagement and competency support were perceived as moderate scores, whereas autonomy support was perceived as a low score. Students in the early phases of study had better attitudes regarding mentoring behaviours. More frequent meetings and longer duration of meetings were significantly associated with better attitudes towards mentoring behaviour.
Originality/value
This paper evaluates contemporary mentoring behaviours in a Malaysian public medical school and contributes to non-western literature on mentoring. These behaviours were reflected in the four domains of the theory-based MBS.
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Karin Crawford, Diane Simpson and Ian Mathews
This collaborative project, undertaken in the context of higher education in England, examined students’ motivations for undertaking a voluntary extra‐curricular mentoring…
Abstract
Purpose
This collaborative project, undertaken in the context of higher education in England, examined students’ motivations for undertaking a voluntary extra‐curricular mentoring role with young people in public care. It also considered students’ perspectives on what they gained from this experience.
Design/methodology/approach
The research was undertaken using a qualitative case study approach, with a focus on students undertaking mentoring in addition to their studies. The case study was a community project that drew on student volunteers to mentor children and young people who are looked after by the local authority. Methods included semi‐structured interviews, focus groups, development of individual exemplars, and the use of Web2 technologies, specifically a blog site and vodcasts. Data were collected between September 2010 and May 2011.
Findings
Findings reported in this paper demonstrate the reasons students engaged with mentoring looked after children as an extra‐curricular activity and the benefits they gained from this experience. As such, institutions and educators might consider how student engagement in mentoring can be valued and embedded in the wider student experience.
Originality/value
This literature provides evidence of mentoring as an important social and political phenomenon. Whilst much is known about benefits to mentees and, to a lesser degree, for mentors in the mentoring relationship, this research explores the issues in more depth by considering the interface between being a mentor and completing undergraduate or postgraduate level studies. In particular it discusses the potential for mentoring to become embedded within the curriculum to ensure education for sustainable futures.
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Tawida Elgattani and Khaled Hussainey
This study aims to investigate the impact of the accounting and auditing organisation for Islamic financial institution (AAOIFI) governance disclosure on the performance…
Abstract
Purpose
This study aims to investigate the impact of the accounting and auditing organisation for Islamic financial institution (AAOIFI) governance disclosure on the performance of Islamic banks (IBs).
Design/methodology/approach
The ordinary least squares regression model was used to test the impact of AAOIFI governance disclosure on the performance of 126 IBs from 8 countries that mandatorily adopt the AAOIFI standards for three years (2013–2015). In this regression model, return on asset (ROA) and return on equity (ROE) are the dependent variables, while AAOIFI governance disclosure is the independent variable. Corporate governance mechanisms, firm characteristics, year dummy and country dummy are used as control variables.
Findings
This paper found an insignificant relationship between AAOIFI governance disclosure and IBs performance.
Research limitations/implications
This study highlighted the implication that the current research may help IBs and encourage them to disclose more information in annual reports, especially those related to AAOIFI governance standards because following good corporate governance leads to good financial performance. The major limitation of the paper is that it is only focussed on two measurements of bank performance – ROA and ROE; it would be good to use other firm performance measures, such as profit margin.
Originality/value
This study provides new empirical evidence on the impact of AAOIFI governance disclosure on IBs performance.
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Michelle Attard Tonna, Eva Bjerkholt and Eimear Holland
The purpose of this paper is to focus on reflective mentoring practices. Teacher mentors are widely known to be an important catalyst for reflection. Through dialogue and…
Abstract
Purpose
The purpose of this paper is to focus on reflective mentoring practices. Teacher mentors are widely known to be an important catalyst for reflection. Through dialogue and professional conversations, teacher mentors can help their mentees to improve their teaching performance by facilitating their discussion of the praxis from different perspectives.
Design/methodology/approach
This qualitative mixed methods study is based on three separate studies from the Republic of Ireland, Malta and Norway involving: mentors of undergraduate student-teachers (U-M, n: 37); mentors of newly qualified teachers (NQT-M, n: 4); student-teachers (ST, n: 16); NQT, n: 8; and university tutors (UT, n: 8). In each study, mentors were provided with varying degrees of education on facilitating critical reflection for mentees. This study sought to draw out what reflective practices were being employed in mentoring across European contexts and what perceived impact they had. A cross-case analysis of data across the three countries was conducted using coding and constant comparison. Triangulation of data was employed across not only cases, but also across multiple methods data sets and across participant types.
Findings
All three studies reveal that mentoring approaches aiming to promote critical reflection have to be based on a developmental approach towards mentoring. They also have to challenge traditional hierarchical relationships and involve a commitment to collaborative, inquiry-oriented approaches towards mentoring.
Research limitations/implications
By bringing different studies of reflection in mentoring practices together, it is possible to gain new knowledge on mentoring in teacher education. However, being a cross-country, cross-context and cross-cultural approach in itself contains certain restrictions.
Originality/value
The authors of this paper propose that professional forms of inquiry depend on the type of relationship and collaboration forged between the teacher mentor and mentee. A cross-case analysis approach provided evidence of reflective practice, which is common across three European countries and offers a snapshot of trends.
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M. Madani, Yasir Khan, Gh. Mahmodi, Naeem Faraz, Ahmet Yildirim and B. Nasernejad
The purpose of this paper is to present the problem of three‐dimensional flow of a fluid of constant density forced through the porous bottom of a circular porous slider…
Abstract
Purpose
The purpose of this paper is to present the problem of three‐dimensional flow of a fluid of constant density forced through the porous bottom of a circular porous slider moving laterally on a flat plate.
Design/methodology/approach
The transformed nonlinear ordinary differential equations are solved via the homotopy perturbation method (HPM) for small as well as moderately large Reynolds numbers. The convergence of the obtained HPM solution is carefully analyzed. Finally, the validity of results is verified by comparing with numerical methods and existing numerical results.
Findings
Close agreement of the two sets of results is observed, thus demonstrating the accuracy of the HPM approach for the particular problem considered.
Originality/value
Interesting conclusions which can be drawn from this study are that HPM is very effective and simple compared to the existing solution method, able to solve problems without using Padé approximants and can therefore be considered as a clear advantage over the N.M. Bujurke and Phan‐Thien techniques.
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Soheil Oveissi, Davood Toghraie, S. Ali Eftekhari and Ali J. Chamkha
This study aims to study the transverse vibration and instabilities of the fluid-conveying single-walled carbon nanotubes (CNTs). To this purpose, the Euler–Bernoulli beam…
Abstract
Purpose
This study aims to study the transverse vibration and instabilities of the fluid-conveying single-walled carbon nanotubes (CNTs). To this purpose, the Euler–Bernoulli beam model is used. Also, the surface effects, small-size effects of the both fluid and structure and two different elastic mediums viscoelastic and Pasternak elastic are investigated.
Design/methodology/approach
To consider the nano-scale for the CNT, the strain-inertia gradient theory is used and to solve the governing equation of motion for the system, the Galerkin’s method is used. The effect of the flow velocity, aspect ratio, characteristic lengths of the mentioned theory, effects of Knudsen number and effects of the Winkler, the Pasternak elastic and the viscoelastic medium on the frequencies and stabilities of the system are studied. The effects of the above parameters on the vibrational behavior are investigated both separately and simultaneously.
Findings
The results show that the critical flow velocity value is increased as the aspect ratio, characteristic lengths, Winkler modulus, shear and damping factors increase. Also, the critical flow velocity is increased by considering the surface effects. In addition, the consequence of increase in the nano-flow-size effects (Knudsen number) is decreasing the critical flow velocity. Moreover, it can be observed that the effect of the shear factor on increasing the critical flow velocity is different from the rest of parameters.
Originality/value
Use of Timoshenko and modified couple stress theories and taking into account Von-Karman expressions for investigating the nonlinear vibrations of triple-walled CNTs buried within Pasternak foundation.
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The purpose of this paper is to consider the thermal‐diffusion and diffusion‐thermo effects on combined heat and mass transfer of a steady magnetohydrodynamic (MHD…
Abstract
Purpose
The purpose of this paper is to consider the thermal‐diffusion and diffusion‐thermo effects on combined heat and mass transfer of a steady magnetohydrodynamic (MHD) convective and slip flow due to a rotating disk with viscous dissipation and Ohmic heating. The main goal of the present study is to find the approximate analytic solutions by the combination of the DTM and the Padé approximants for this problem.
Design/methodology/approach
A new method, namely the DTM‐Padé technique, which is a combination of the differential transform method and the Padé approximation, is employed.
Findings
Graphical results for fluids of medium molecular weight (H2, air) are presented to investigate influence of the slip parameter, magnetic field parameter M, Eckert Ec, Schmidt Ec, Dufour Du and Soret Sr numbers on the profiles of the dimensionless velocity, temperature and concentration distributions. In order to show the effectiveness of the DTM‐Padé, the results obtained from the DTM‐Padé are compared with available solutions obtained using shooting method to generate the numerical solution.
Originality/value
This technique (DTM‐Padé) is extended to give solutions for nonlinear differential equations with boundary conditions at the infinity.
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