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1 – 10 of over 2000Saeed Dinarvand, Seyed Mehdi Mousavi, Mohammad Yousefi and Mohammadreza Nademi Rostami
The purpose of this paper is to study the steady laminar magnetohydrodynamics (MHD) flow of a magnesium oxide-silver/water hybrid nanofluid along a horizontal slim needle with…
Abstract
Purpose
The purpose of this paper is to study the steady laminar magnetohydrodynamics (MHD) flow of a magnesium oxide-silver/water hybrid nanofluid along a horizontal slim needle with thermal radiation by considering dual solutions.
Design/methodology/approach
It is assumed that the needle can move in the same or opposite direction of the free stream. Also the solid phase and fluid phase are in thermal equilibrium. The basic partial differential equations become dimensionless using a similarity transformation method. Moreover, problem coding is accomplished using the finite difference method. The emerging parameters are nanoparticles mass (0–40 gr), base fluid mass (100 gr), needle’s size (0.001–0.2), magnetic field parameter, velocity ratio parameter, radiation parameter and Prandtl number (6.2).
Findings
With help of the stability analysis, it is shown that always the first solutions are physically stable. Results indicate that the magnetic parameter and the second nanoparticle’s mass limit the range of the velocity ratio parameter for which the solution exists. Besides, the magnetic parameter leads to decrease of quantities of engineering interest, i.e. skin friction coefficient and local Nusselt number.
Originality/value
To the best of the authors’ knowledge, no one has ever attempted to study the present problem through a mass-based model for hybrid nanofluid. Moreover, the dual solutions for the problem are new. Indeed, the results of this paper are purely original and the numerical achievements were never published up to now. Finally, the authors expect that the present investigation would be useful in hot-wire anemometer or shielded thermocouple for measuring the velocity of the wind, etc.
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Use of programme package ADAMS to simulate the sewing machine mechanisms is presented within this contribution. The simulation of needle bar mechanism was carried out. The…
Abstract
Use of programme package ADAMS to simulate the sewing machine mechanisms is presented within this contribution. The simulation of needle bar mechanism was carried out. The influence of velocity changes of the main shaft on velocities and acceleration of sewing needle in the penetration area is described on the basis of simulation results. Achieved data could be used for calculation of needle penetration force. The influence of length modification of needle bar mechanism elements on sewing needle velocity and acceleration is also presented. This analysis could contribute to better understanding of sewing machine activity.
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Iskandar Waini, Anuar Ishak and Ioan Pop
This paper aims to examine the effect of Dufour and Soret diffusions on Al2O3-water nanofluid flow over a moving thin needle by using the Tiwari and Das model.
Abstract
Purpose
This paper aims to examine the effect of Dufour and Soret diffusions on Al2O3-water nanofluid flow over a moving thin needle by using the Tiwari and Das model.
Design/methodology/approach
The governing equations are reduced to the similarity equations using similarity transformations. The resulting equations are programmed in Matlab software through the bvp4c solver to obtain their solutions. The features of the skin friction, heat transfer and mass transfer coefficients, as well as the velocity, temperature and concentration profiles for different values of the physical parameters, are analysed and discussed.
Findings
The non-uniqueness of the solutions is observed for a certain range of the physical parameters. The authors also notice that the bifurcation of the solutions occurs in which the needle moves toward the origin (λ < 0). It is discovered that the first branch solutions of the skin friction coefficient and the heat transfer coefficients increase, but the mass transfer coefficient decreases in the presence of nanoparticle. Additionally, the simultaneous effect of Dufour and Soret diffusions tends to enhance the heat transfer coefficient; however, dual behaviours are observed for the mass transfer coefficient. Further analysis shows that between the two solutions, only one of them is stable and thus physically reliable in the long run.
Originality/value
The problem of Al2O3-water nanofluid flow over a moving thin needle with Dufour and Soret effects are the important originality of the present study. Besides, the temporal stability of the dual solutions is examined for time.
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G.K. Ramesh, J.K. Madhukesh, Emad H. Aly and Ioan Pop
The purpose of this paper is to study the steady biomagnetic hybrid nanofluid (HNF) of oxytactic microorganisms taking place over a thin needle with a magnetic field using the…
Abstract
Purpose
The purpose of this paper is to study the steady biomagnetic hybrid nanofluid (HNF) of oxytactic microorganisms taking place over a thin needle with a magnetic field using the modified Buongiorno’s nanoliquid model.
Design/methodology/approach
On applying the appropriate similarity transformations, the governing partial differential equations were transformed into a set of ordinary differential equations. These equations have been then solved numerically using Runge–Kutta–Fehlberg method of fourth–fifth order programming in MAPLE software. Features of the velocity profiles, temperature distribution, reduced skin friction coefficient, reduced Nusselt number and microorganisms’ flux, for different values of the governing parameters were analyzed and discussed.
Findings
It was observed that as the needle thickness and solid volume fraction increase, the temperature rises, but the velocity field decreases. For a higher Peclet number, the motile microorganism curve increases, and for a higher Schmidt number, the concentration curve rises.
Originality/value
On applying the modified Buongiorno’s model, the present results are original and new for the study of HNF flow and heat transfer past a permeable thin needle.
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Himanshu Upreti and Manoj Kumar
The purpose of this paper is to examine the effect of non-linear thermal radiation, Joule heating and viscous dissipation on the mixed convection boundary layer flow of MHD…
Abstract
Purpose
The purpose of this paper is to examine the effect of non-linear thermal radiation, Joule heating and viscous dissipation on the mixed convection boundary layer flow of MHD nanofluid flow over a thin moving needle.
Design/methodology/approach
The equations directing the flow are reduced into ODEs by implementing similarity transformation. The Runge–Kutta–Fehlberg method with a shooting technique was implemented.
Findings
Numerical outcomes for the coefficient of skin friction and the rate of heat transfer are tabulated and discussed. Also, the boundary layer thicknesses for flow and temperature fields are addressed with the aid of graphs.
Originality/value
Till now, no numerical study investigated the combined influence of Joule heating, non-linear thermal radiation and viscous dissipation on the mixed convective MHD flow of silver-water nanofluid flow past a thin moving needle. The numerical results for existing work are new and their novelty verified by comparing them with the work published earlier.
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M. Gnaneswara Reddy, P. Vijaya Kumari, G. Upender Reddy, K. Ganesh Kumar and B. C. Prasannakumara
The main theme of this paper is the effect of viscous dissipation Darcy–Forchheimer flow and heat transfer augmentation of a viscoelastic fluid over an incessant moving needle.
Abstract
Purpose
The main theme of this paper is the effect of viscous dissipation Darcy–Forchheimer flow and heat transfer augmentation of a viscoelastic fluid over an incessant moving needle.
Design/methodology/approach
The governing partial differential equations of the current problem are diminished into a set of ordinary differential equations using requisite similarity transformations. Energy equation is extended by using Cattaneo–Christov heat flux model with variable thermal conductivity. By applying boundary layer approximation system of equations is framed.
Findings
Convective condition is also introduced in this analysis. Obtained set of similarity equations are then solved with the help of efficient numerical method four–fifth-order RKF-45.
Originality/value
The outcomes of various pertinent parameters on the velocity, temperature distributions are analysed by using portraits.
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Iskandar Waini, Anuar Ishak and Ioan Pop
The purpose of this paper is to study the steady mixed convection hybrid nanofluid flow and heat transfer past a vertical thin needle with prescribed surface heat flux.
Abstract
Purpose
The purpose of this paper is to study the steady mixed convection hybrid nanofluid flow and heat transfer past a vertical thin needle with prescribed surface heat flux.
Design/methodology/approach
The governing partial differential equations are transformed into a set of ordinary differential equations by using a similarity transformation. The transformed equations are then solved numerically using the boundary value problem solver (bvp4c) in Matlab software. The features of the skin friction coefficient and the local Nusselt number as well as the velocity and temperature profiles for different values of the governing parameters are analyzed and discussed.
Findings
It is found that dual solutions exist for a certain range of the mixed convection parameter where its critical values decrease with the increasing of the copper (Cu) nanoparticle volume fractions and for the smaller needle size. It is also observed that the increasing of the copper (Cu) nanoparticle volume fractions and the decreasing of the needle size tend to enhance the skin friction coefficient and the local Nusselt number on the needle surface. A temporal stability analysis is performed to determine the stability of the dual solutions in the long run, and it is revealed that only one of them is stable, while the other is unstable.
Originality/value
The problem of hybrid nanofluid flow and heat transfer past a vertical thin needle with prescribed surface heat flux is the important originality of the present study where the dual solutions for the opposing flow are obtained.
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The aim of this article is to provide Dr Bailey Jackson's perspective on institutional and systemic barriers to full inclusion of diverse faculty in higher education through the…
Abstract
Purpose
The aim of this article is to provide Dr Bailey Jackson's perspective on institutional and systemic barriers to full inclusion of diverse faculty in higher education through the lens of the multicultural organizational development (MCOD) model. Dr Jackson is renowned for his work on social justice, diversity and multiculturalism.
Design/methodology/approach
This is a personal interview with Dr Bailey Jackson. This interview provides insight on institutional level change efforts through the MCOD framework, a perspective on why institutions get stuck on the way to becoming healthy multicultural institutions, and the effect on moving the needle on faculty diversity in institutions of higher education.
Findings
The institutional obstacles and barriers tend to be centered around misalignment with the mission, vision and core values, and how those are formulated to include diversity and inclusion. Faculty diversity is only one component in dealing with the health of any organization or the academy as a whole. If institutions focus on diversity faculty in an unhealthy system, they will encounter limitations on how much the institution will develop on the MCOD continuum. The health of the overall system is going to affect the approach to faculty diversity.
Practical implications
Dr Jackson provides insight on his work with the MCOD framework and specifically the overall health of the institution as critical to faculty diversity initiatives. Questions to help institutions begin to assess themselves and identify changes required to move toward Multicultural within the context of faculty diversity are provided.
Originality/value
Through a series of questions, insight from Dr Jackson on why institutions get stuck in moving the needle on faculty diversity through the lens of the MCOD framework is gained.
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Xiaohui Xie, Cui Ma, Qiang Sun and Ruxu Du
Bar‐tacking is a specialized sewing stitch designed to provide immense tensile strength to the garment which requires a high‐speed precision bar‐tacking sewing machine. This paper…
Abstract
Purpose
Bar‐tacking is a specialized sewing stitch designed to provide immense tensile strength to the garment which requires a high‐speed precision bar‐tacking sewing machine. This paper aims to present an event‐driven multi‐axis cooperative control method for a bar‐tacking sewing machine.
Design/methodology/approach
The control method consists of two parts: the multi‐axis cooperative control and the needle stop positioning control. The challenges include the high speed and the precision. For example, the needle must stop at a set position in milliseconds.
Findings
The presented multi‐axis cooperative control can ensure the high speed response and the precision of the cooperative control. The needle stop positioning control is based on a combination of the velocity control and the position control with velocity feed‐forward and limitation.
Research limitations/implications
The bar‐tacking sewing machine requires high‐speed start and stop response and coordination of displacement and velocity only at some given points. Therefore, the conventional multi‐axis cooperative control methods are not suitable. In addition, it requires high‐speed precision control under varying loading conditions.
Practical implications
While there are a number of commercial textile machines available in the market, designing a smart bar‐tacking sewing machine with good speed and precision performance remains a challenge.
Originality/value
The bar‐tacking sewing machine requires highly accurate multi‐axes cooperative control. The presented event‐driven multi‐axis control method is effective. It has not only the required high accuracy but also the fast time response.
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Robin S. Grenier, Peter Williams and Yonjoo Cho
The purpose of this paper is to conclude this special issue on innovation in qualitative research by addressing the preceding papers in relation to the work of Human Resource…
Abstract
Purpose
The purpose of this paper is to conclude this special issue on innovation in qualitative research by addressing the preceding papers in relation to the work of Human Resource Development (HRD) scholars and scholar-practitioners, consider the implications to the field of HRD and point to additional directions for innovative qualitative approaches. The authors use the term “innovative” to mean either an approach (or technique) that is newly conceived or one that is new to HRD (or little used).
Design/methodology/approach
The authors reviewed the papers in the special issue, identified other innovative qualitative approaches from the HRD literature and described briefly additional innovative approaches from other fields to suggest future directions for HRD professionals.
Findings
In this review, the authors noted the relatively few approaches to qualitative research that have been used regularly in HRD literature and suggested further innovative approaches that could deepen the understanding of organizations, including narrative, visual and indigenous methods, among others.
Research limitations/implications
This paper provides for HRD scholars an overview of a few qualitative research methodologies that are new to HRD and identifies additional approaches and epistemological challenges that could be valuable for future inquiry into complex organizations by HRD scholars and practitioners.
Practical implications
The authors suggest various feasible approaches and tools for HRD professionals to inquire into their practice in organizations to identify needs, evaluate outcomes and inquire into socially complex issues.
Originality/value
This study’s intent is to encourage the use of various innovative qualitative inquiry approaches when appropriate to understand and transform organizations. In particular, this study encourages the approaches that center the voices and experiences of those being studied and emphasizes the ways of listening to voices from the margins that may have been ignored previously.
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