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The purpose of the study is to propose a novel implementation of twisted tape in sinusoidal wavy-walled tubes to enhance the rate of heat transfer without compromising thermal efficiency. The study numerically investigates the fluid flow characteristics and analyzes the effect of different geometrical configurations, including wall wave amplitude, tape twist angles and nanoparticle volume fractions, on heat transfer improvement and performance factor.

This problem is numerically investigated using computational fluid dynamics, and the method is the finite volume method. A two-phase mixture model is used for nanofluid modeling.

The study investigated the effect of wall waviness, twisted tape, and nanoparticles on forced convective heat transfer and friction factor behavior in laminar pipe flow in three different Reynolds number regimes. The results showed that implementing twisted tape in wavy tubes significantly increased the rate of heat transfer and the performance factor, with the best twist ratio between 90 and 180°. Adding nanoparticles also enhanced heat transfer and performance factor, but to a lesser extent than wavy wall-twisted tape combinations. The study suggests selecting a proper combination of wavy wall and twisted tape at each Reynolds number to achieve an optimum solution.

To the best of the authors’ knowledge, the implementation of the selected passive methods in sinusoidal wavy tubes has not been studied before, and no previous studies have taken into account such a mix of heat transfer improvement techniques.

The purpose of this paper is to characterize and identify the existing studies on the relationship between technological media and development

The authors conducted a systematic mapping study to identify and analyze the related literature. The authors identified 196 primary studies, dated from 2000 to 2017 and categorized them with respect to research focus, types of research and research method.

A total of 97 studies were identified and mapped, synthesizing the available evidence on the relationship between technological media and development. “Social development” with 54 articles and “communication” with 34 articles were the dominant research focus. Regarding the research type, “Solution proposal” is the most frequently employed research type. “Case study,” “discussion paper” and “interview,” respectively were the most used research methods. However, “SNA,” “focus group” and “time series” were used less often. “Solution proposal” was the most common research type between 2015 and 2017, and after that “philosophical paper” was the dominant research paper type. Further, the number of publications has increased between 2006 and 2017.

This mapping study is the first systematic exploration of the state-of-art on technological media-development nexus. The existing body of knowledge is limited to a few high quality studies.

This study aims to investigate the relationship between information technology and internal controls of state agencies in Iran.

The research population includes all auditors and managers working in public sector. Data collection instrument is a questionnaire designed by the researcher and administrated during March 5, 2016. The collected data are analyzed through descriptive and inferential statistics (binomial test).

The findings of the research show that there is a significant relationship between information technology and internal controls (administrative, financial and accounting controls, risk assessment, information and communication, control activities and monitoring). Moreover, the alteration of data collection methods (from traditional to modern) and the written instructions (in information technology) have a positive effect on the internal control and its subscales.

With regard to the emphasis on the development of computer application and the use of new processing facilities and the exchange of information and its specific controlling consequences, this is an innovative research.

The purpose of this study is to investigate the moderating role of knowledge management (KM) strategies in developing the effect of intellectual capital (IC) on innovation for small- and medium-sized enterprises (SMEs). Specifically, the current study explores how different interactions between IC and KM strategies lead to more powerful innovation in SMEs.

This study analyzes survey responses from 170 owners/managers of SMEs in Iran. The study uses partial least square structural equation modeling methods within Smart PLS software.

This study reveals that first IC has an excellent level of engagement with both incremental and radical types of innovation, but its engagement level with radical innovation is higher than that for incremental innovation. Second, the human capital component of IC has a direct positive impact on radical innovation although it has no significant impact on incremental innovation. Third, the personalization strategy of KM positively moderates the impact of human capital on both incremental and radical innovation.

This paper is an empirical attempt in SMEs to combine IC and KM strategies to strengthen innovation. It presents research community for SMEs of a developing country that has been investigated in a limited way compared to large firms of developed nations and provides valuable insights into further research.

The purpose of this paper is to provide a theoretical picture of the concept of knowledge creation and then investigate the effects on it of such variables as social capital and organizational culture.

The population of this study includes faculty members of the University of Isfahan (Iran) in 2008 (476 cases). From among these cases, 142 cases were selected based on the Cochran formula. Survey was used as the research method and a questionnaire was used for data collection. Pearson correlation “r” and multi‐variable regression were employed, and in the next stage, through drawing the model of structural equations, the direct effects, indirect effects and total effects of independent variables on the dependent variable were investigated, based on path analysis model. SPSS and LISREL were employed for statistical analysis.

The results revealed that social capital and organizational culture had meaningful effect on knowledge creation. The analysis showed that the independent variables mentioned above could determine 36 percent of the effects of the dependent variable.

The findings are based, in the main, on an extensive, single university study; therefore it is necessary to be cautious about generalizing the result of this study to other universities in Iran.

The paper can contribute to organizations through providing a holistic picture of the role of knowledge creation in organizations (especially universities).

High torque ripple is the significant challenge of the synchronous reluctance machine in household electric appliances, electric vehicles and so on. This paper aims to present an optimized design of a synchronous reluctance rotor structure to reduce the torque ripple with improving the average torque by the particle swarm optimization (PSO) algorithm.

The optimization of rotor geometries has been investigated. Most of the rotor parameters such as the width of iron parts, the width of barriers along d and q axes and the endpoint angle of barriers are optimized by a new method using the PSO algorithm. After optimization, the resulted optimum design along with the initial design is simulated by two-dimensional finite element method and results are compared. At the end, a prototype is constructed and tested. Results of the experiment are compared with the simulation results where acceptable adoption is yielded.

Minimizing the torque ripple without losing the average torque is an important achievement of the synchronous reluctance motor (SynRM) optimization; furthermore, the finite element analysis and experimental results indicate that the torque ripple of the SynRM with the optimized rotor is reduced significantly. Also, increasing the number of optimization parameters can effectively obtain an accurate shape of the SynRM barrier.

Because of the high number of parameters in synchronous reluctance rotors, the majority of proposed optimizations did not use all geometric parameters of the rotor and tried to simplify the optimization by ignoring several optimization parameters or reducing the number of flux barriers. In this optimization, most of the rotor parameters have been used to achieve the precise barrier shape with the aim of reducing the torque ripple in SynRM.

The purpose of this study is to reduce energy consumption in bakeries. Due to fulfill this demand, quite a few parameters such as energy and exergy efficiency, energy waste and fuel consumption by different traditional flatbreads bakeries (Sangak, Barbari, Taftun and Lavash should be monitored and their roles should not be neglected.

In the present study, experimental measurements and mathematical modeling are used to scrutinize and investigate the effects of the aforementioned parameters on energy consumption by bakeries.

The results show that by doing reported methods in this paper, the wasted energy of the walls can be decreased by about 65 per cent; and also, by controlling the combustion reaction to perform with 5 per cent excess air, the wasted energy of excess air declines by about 90 per cent. And finally, the energy and exergy efficiency of bakeries is increased, and as a result, the annual energy consumption of Sangak, Barbari, Taftun and Lavash bakeries diminish about 71, 59, 57 and 40 per cent, respectively.

As evidenced by the literature review, it can be observed that neither numerical studies nor experimental investigations have been conducted about energy and exergy analyses of Iranian machinery traditional flatbread bakeries. It is clear that due to a high preference of Iranians to use the traditional bread and also the popularity of baking this kind of bread in Iran, if it is possible to enhance the traditional oven conditions to decrease the loss of natural gas instead of industrializing the bread baking, the energy consumption in the country can be optimized.

This paper aims to examine how technological media accelerates sustainable development. Further, the mediating role of good governance and society empowerment would be investigated.

A questionnaire survey was conducted among 450 students at the level of higher education using stratified sampling plan. Following a two-step approach, a measurement model was estimated and then a structural model was analyzed to evaluate five proposed hypotheses.

The research results indicate that technological media has a direct and positive effect on good governance, empowerment and sustainable development; technological media has an indirect and positive influence on sustainable development via good governance and empowerment as mediating variables; good governance and empowerment are significant antecedents of sustainable development.

The research examines the relationship among technological media, good governance, empowerment and sustainable development, thus contributing to sustainable development literature theoretically. In addition, relevant implications are provided for policymakers as to how to accelerate development sustainably across their countries.

This paper aims to study the thermal and thermo-hydraulic performances of ferro-nanofluid flow in a three-dimensional trapezoidal microchannel heat sink (TMCHS) under uniform heat flux and magnetic fields.

To investigate the effect of direction of Lorentz force the magnetic field has been applied: transversely in the x direction (Case I);transversely in the y direction (Case II); and parallel in the z direction (Case III). The three-dimensional governing equations with the associated boundary conditions for ferro-nanofluid flow and heat transfer have been solved by using an element-based finite volume method. The coupled algorithm has been used to solve the velocity and pressure fields. The convergence is reached when the accuracy of solutions attains 10–6 for the continuity and momentum equations and 10–9 for the energy equation.

According to thermal indicators the Case III has the best performance, but according to performance evaluation criterion (PEC) the Case II is the best. The simulation results show by increasing the Hartmann number from 0 to 12, there is an increase for PEC between 845.01% and 2997.39%, for thermal resistance between 155.91% and 262.35% and ratio of the maximum electronic chip temperature difference to heat flux between 155.16% and 289.59%. Also, the best thermo-hydraulic performance occurs at Hartmann number of 12, pressure drop of 10 kPa and volume fraction of 2%.

The embedded electronic chip on the base plate generates heat flux of 60 kW/m2. Simulations have been performed for ferro-nanofluid with volume fractions of 1%, 2% and 3%, pressure drops of 10, 20 and 30 kPa and Hartmann numbers of 0, 3, 6, 9 and 12.

The authors obtained interesting results, which can be used as a design tool for magnetohydrodynamics micro pumps, microelectronic devices, micro heat exchanger and micro scale cooling systems.

Review of the literature indicated that there has been no study on the effects of magnetic field on thermal and thermo-hydraulic performances of ferro-nanofluid flow in a TMCHS, so far. In this three dimensional study, flow of ferro-nanofluid through a trapezoidal heat sink with five trapezoidal microchannels has been considered. In all of previous studies, in which the effect of magnetic field has been investigated, the magnetic field has been applied only in one direction. So as another innovation of the present research, the effect of applying magnetic field direction (transverse and parallel) on thermo-hydraulic behavior of TMCHS is investigated.

This study aims to identify and compare the measurement models of earnings management (EM) appropriate to the Iranian Islamic banking system. The importance of reported profit figures has motivated business executives, who also perform financial reporting, to manipulate these figures. These measures are referred to as “earnings management,” which negatively influence the quality of reported earnings and financial statements' reliability.

In this study, four methods, namely, Jones (1991), modified Jones (Dechow et al., 1995), Kasznik (1999) and Kothari et al. (2005), were used to measure the EM index in 25 Iranian Islamic banks (IBs) registered with the Tehran Stock Exchange and/or the Central Bank of Iran. The study covered the period 2005–2020. Following the aforementioned methods, this research implemented templates that were repeatedly tested in subsequent studies using accruals to discover EM.

The results show that the Kasznik (1999) model is the preferred and compatible model with the Iranian Islamic banking system's accrual behaviour due to the consistency of the measurement coefficients with theoretical and previous research findings. Therefore, total accruals, including discretionary accruals and non-discretionary accruals, have the most correspondence with (1) property, machinery and equipment; (2) the change in cash flow from operating activities; and (3) the difference of change in revenue (ΔREV) and change in net receivable accounts (ΔREC).

This is the first investigation in the Iranian Islamic banking system. The research contributes to the Iranian Islamic banking system literature on the implements of EM, which could be appealed to in the context of developing countries like Iran. Finally, this study highlights the different EM capabilities in Islamic banking systems similar to the Iranian banking arrangement.