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1 – 10 of over 8000The purpose of this paper is to simulate flow inside differentially heated rotating cavity using two different formulations; one using Navier‐Stokes (NS) equations derived in…
Abstract
Purpose
The purpose of this paper is to simulate flow inside differentially heated rotating cavity using two different formulations; one using Navier‐Stokes (NS) equations derived in non‐inertial (rotating) frame of reference and the other using NS equations in inertial frame of reference. Then to compare the results obtained from these formulations to find their merits and demerits.
Design/methodology/approach
The NS equations for both non‐inertial and inertial formulations are written in artificial compressibility form before discretizing them by a high resolution finite volume method. The dual time steeping approach of Jameson is used for time accuracy in both the formulations. Arbitrary Lagrangian Eulerian (ALE) approach is used for taking care of moving boundary problem arising in the inertial formulation. A newly developed HLLC‐AC Riemann solver for discretizing convective fluxes and central differencing for discretizing viscous fluxes are used in the finite volume approach. Results for both the formulations are first validated with test cases reported in literature. Then the results of the two formulations are compared among themselves.
Findings
Results of the non‐inertial formulation obtained by the proposed method are found to match well with those reported in literature. The results of both the formulations match well for low rotational speeds of the cavity. The discrepancies between the results of the two formulations progressively increase with the increase in rotational speed. Implicit treatment of the source term is found to reduce the discrepancies.
Practical implications
The present approach is useful for accurate prediction of flow feature and heat transfer characteristic in case of applications such as manufacturing of single wafer crystal for semiconductor and in numerous metallurgical processes.
Originality/value
The ALE formulation is used for the first time to simulate a differentially heated rotating cavity problem. The attempt to compare non‐inertial and inertial formulations is also reported for the first time. Implicit treatment of the source term leading to change in solution accuracy is one of the important findings of the present investigation.
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Addresses the standardization of the measurements and the labels for concepts commonly used in the study of work organizations. As a reference handbook and research tool, seeks to…
Abstract
Addresses the standardization of the measurements and the labels for concepts commonly used in the study of work organizations. As a reference handbook and research tool, seeks to improve measurement in the study of work organizations and to facilitate the teaching of introductory courses in this subject. Focuses solely on work organizations, that is, social systems in which members work for money. Defines measurement and distinguishes four levels: nominal, ordinal, interval and ratio. Selects specific measures on the basis of quality, diversity, simplicity and availability and evaluates each measure for its validity and reliability. Employs a set of 38 concepts ‐ ranging from “absenteeism” to “turnover” as the handbook’s frame of reference. Concludes by reviewing organizational measurement over the past 30 years and recommending future measurement reseach.
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Mehrdad Vasheghani Farahani, Omid Rezaei and Milad Masoomzadeh
This paper reports on a quasi-experimental research performed in the field of reading comprehension and translation quality. The purpose of this paper is to investigate the…
Abstract
Purpose
This paper reports on a quasi-experimental research performed in the field of reading comprehension and translation quality. The purpose of this paper is to investigate the comparative effect of explicit vs implicit reading comprehension skills on translation quality of Iranian translation students at BA level.
Design/methodology/approach
The design of this research was quasi-experimental in nature. This design was preferred in this study, as it was impossible to assign random sampling to the subjects and apply a true experimental design. The research in hand was also a comparative group design research in a sense that it was supposed to compare two reading comprehension methods (explicit vs implicit) with different treatments.
Findings
In light of this research, some conclusions can be drawn. It can be concluded that there is a positive and direct relationship between reading comprehension and translation, as the first step of translation is to understand the content of the source text (Reid, 1993).
Research limitations/implications
The reading comprehension ability of translation students should be enhanced in their undergraduate classes so that they can better understand the source text and produce a more fluent translation. In order to teach reading comprehension skills, both implicit and explicit techniques can be applied; however, it is better if the subjects receive explicit instruction, as this technique may have more positive results.
Originality/value
Various researchers have explored explicit and implicit instructions on such areas as reading, speaking and listening (see, e.g. Jalilifar and Alipour, 2007; Vahid Dastjerdi and Shirzad, 2010; Negahi and Nouri, 2014; Khanbeiki and Abdolmanafi-Rokni, 2015; Khoii et al., 2015; Mostafavi and Vahdany 2016; Rahimi and Riasati, 2017). Although the results of these studies have shown the positive impacts of both explicit and implicit teaching, explicit has more positive impacts. However, the review of the literature shows that explicit and implicit reading comprehension skills have not been investigated in relation to teaching translation and their possible impacts on translation quality.
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Mehrdad Vasheghani Farahani, Omid Rezaei and Milad Masoomzadeh
The purpose of this paper (experimental–comparative research) is to investigate the possible impacts of explicit and implicit teaching Persian structures and editing methods on…
Abstract
Purpose
The purpose of this paper (experimental–comparative research) is to investigate the possible impacts of explicit and implicit teaching Persian structures and editing methods on the translation performance of the Iranian undergraduate translation students.
Design/methodology/approach
This research enjoyed a quasi-experimental design. A quasi-experimental research design was used in this research, as it was impossible to assign random sampling to the subjects. In addition, this research was a comparative group study as there were two experimental groups with two different treatments and one control group with placebo. Table I represents the design of the research.
Findings
The results showed that before the treatment there were no significant differences between three groups in terms of translation performance; however, after treatment, the results indicated a statistically significant difference between two experimental groups and treatment group. Moreover, explicit instruction yielded more positive results than the implicit group.
Originality/value
Although research in the field of translation assessment and quality in relation to target language are prevalent and in spite of the abundance of research in the field of implicit/explicit instructions in second language teaching and learning, there is no research (to the best knowledge of authors) which looks at translation performance from teaching structures and editing methods of target language perspective with the focus of explicit and implicit (in an English–Persian context).
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C.P.T. GROTH and J.J. GOTTLIEB
Partially‐decoupled upwind‐based total‐variation‐diminishing (TVD) finite‐difference schemes for the solution of the conservation laws governing two‐dimensional non‐equilibrium…
Abstract
Partially‐decoupled upwind‐based total‐variation‐diminishing (TVD) finite‐difference schemes for the solution of the conservation laws governing two‐dimensional non‐equilibrium vibrationally relaxing and chemically reacting flows of thermally‐perfect gaseous mixtures are presented. In these methods, a novel partially‐decoupled flux‐difference splitting approach is adopted. The fluid conservation laws and species concentration and vibrational energy equations are decoupled by means of a frozen flow approximation. The resulting partially‐decoupled gas‐dynamic and thermodynamic subsystems are then solved alternately in a lagged manner within a time marching procedure, thereby providing explicit coupling between the two equation sets. Both time‐split semi‐implicit and factored implicit flux‐limited TVD upwind schemes are described. The semi‐implicit formulation is more appropriate for unsteady applications whereas the factored implicit form is useful for obtaining steady‐state solutions. Extensions of Roe's approximate Riemann solvers, giving the eigenvalues and eigenvectors of the fully coupled systems, are used to evaluate the numerical flux functions. Additional modifications to the Riemann solutions are also described which ensure that the approximate solutions are not aphysical. The proposed partially‐decoupled methods are shown to have several computational advantages over chemistry‐split and fully coupled techniques. Furthermore, numerical results for single, complex, and double Mach reflection flows, as well as corner‐expansion and blunt‐body flows, using a five‐species four‐temperature model for air demonstrate the capabilities of the methods.
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– The purpose of this paper is to report a novel formulation of convective heat transfer source term for the case of flow through porous medium.
Abstract
Purpose
The purpose of this paper is to report a novel formulation of convective heat transfer source term for the case of flow through porous medium.
Design/methodology/approach
The novel formulation is obtained by analytical solution of an idealized dual problem. Computations are performed by dedicated tool for fixed bed combustion named GRATECAL and developed by the authors. However, the proposed method can also be applied to other porous media flow problems.
Findings
The new source term formulation is unconditionally stable and it respects exponential decay of temperature difference between the fluid and porous solid medium.
Practical/implications
The results of this work are applicable in the simulation of convective heat transfer between the fluid and porous medium. Applications include e.g. fixed bed combustion, catalytic reactors and lime kilns.
Originality/value
The reported solution is believed to be original. It will be useful to all involved in numerical simulations of fluid flow in porous media with convective heat transfer.
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The object of this research is the reconstruction of the existing legal response by European Union states to the phenomenon of immigration. It seeks to analyse the process of…
Abstract
Purpose
The object of this research is the reconstruction of the existing legal response by European Union states to the phenomenon of immigration. It seeks to analyse the process of conferral of protection.
Design/methodology/approach
One main dimension is selected and discussed: the case law of the national courts. The study focuses on the legal status of immigrants resulting from the intervention of these national courts.
Findings
The research shows that although the courts have conferred an increasing protection on immigrants, this has not challenged the fundamental principle of the sovereignty of the states to decide, according to their discretionary prerogatives, which immigrants are allowed to enter and stay in their territories. Notwithstanding the differences in the general constitutional and legal structures, the research also shows that the courts of the three countries considered – France, Germany and Spain – have progressively moved towards converging solutions in protecting immigrants.
Originality/value
The research contributes to a better understanding of the different legal orders analysed.
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Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some…
Abstract
Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.
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Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community…
Abstract
Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.
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