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Article
Publication date: 1 October 2019

Soroush Sadripour, Mohammad Estajloo, Seyed Abdolmehdi Hashemi, Ali J. Chamkha and Mahmoud Abbaszadeh

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 5 October 2021

Mohammad Reza Naeimi, Karim Abbaszadeh and Reza Nasiri-Zarandi

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…

252

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 40 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 17 June 2019

Behrouz Mozafari, Ali Akbar Abbasian Arani, Ghanbar Ali Sheikhzadeh and Mahmoud Salimi

The purpose of this paper is to study the effects of using different Brownian models on natural and mixed convection fluid flow and heat transfer inside the square enclosure…

Abstract

Purpose

The purpose of this paper is to study the effects of using different Brownian models on natural and mixed convection fluid flow and heat transfer inside the square enclosure filled with the AlOOH–water nanofluid.

Design/methodology/approach

Due to fulfill of this demand, five different models for the effective thermal conductivity and viscosity of the nanofluid are considered. The following results are presented for the Ra=107 to 1010 and Ri=0.01 to 100, whereas the volume fraction of the nanoparticles is varied from φ = 0.01 to 0.04.

Findings

According to the obtained results, increasing of Rayleigh number and reduction of Richardson number leads to the higher values of the average Nusselt number and entropy generation. Also, it is realized that, variation trend of the average Nusselt number and entropy generation in all cases is increasing by growing the volume fraction. It is found that the obtained average Nusselt numbers and entropy generations with Koo and Kleinstreuer are the highest among all the studied cases, and it is followed by Patel, Vajjha and Das, Corcione and Maxwell–Brinkman models, respectively.

Originality/value

Based on the results of present investigation, the Nusselt number difference predicted between the Maxwell–Brinkman model (as constant-property model) and Koo and Kleinstreuer model is about 7.84 per cent at 0.01 per cent volume fraction and 5.47 per cent at 0.04 per cent volume fraction for the Rayleigh number equal to 107. The entropy generation difference predicted between the two above studied model is about 8.05 per cent at 0.01 per cent volume fraction and 5.86 per cent at 0.04 per cent volume fraction for the Rayleigh number equal to 107. It is observed that using constant-property model has a significant difference in the obtained results with the results of other variable-property models.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Open Access
Article
Publication date: 8 August 2022

Mahdi Ghaemi Asl and Mohammad Ghasemi Doudkanlou

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…

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Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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).

Originality/value

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.

Details

ISRA International Journal of Islamic Finance, vol. 14 no. 3
Type: Research Article
ISSN: 0128-1976

Keywords

Article
Publication date: 21 January 2020

Mahmoud Mawed, Vinay Tilani and Karima Hamani

Green retrofitting is acknowledged as an essential strategy toward achieving long-term sustainability in the built environment. To implement this strategy successfully, the role…

Abstract

Purpose

Green retrofitting is acknowledged as an essential strategy toward achieving long-term sustainability in the built environment. To implement this strategy successfully, the role of facility managers cannot be ignored. The purpose of this paper is to investigate present practices that are used in managing the existing facilities, to highlight the elements that govern the process of green retrofitting, and discuss the efforts and contribution of facility managers in enhancing the environmental performance of the existing facilities stock in the United Arab Emirates (UAE).

Design/methodology/approach

This study suggests that an adequate level of awareness of the benefits of green retrofit amongst owners and decision-makers is mostly dependent on facilities management (FM) professionals, who must establish effective communication channel with senior management. FM professionals in the UAE are well equipped and competent in greening existing buildings and can simultaneously lead a building to the path of achieving green building certification.

Findings

To examine the role of FM in a green retrofit and its current status in the UAE built environment, a two-step qualitative method was adopted. The study started by conducting semi-structured interviews with FM professionals and then assessing the insights obtained from the interviews against an actual case study of a LEED Existing Building certified facility.

Research limitations/implications

Interviews were limited to FM professionals in the private sector and the results from one case study should be considered cautiously.

Originality/value

This paper emphasizes the primordial role of FM professionals in promoting green retrofit in the UAE.

Details

Journal of Facilities Management , vol. 18 no. 1
Type: Research Article
ISSN: 1472-5967

Keywords

Article
Publication date: 7 August 2020

Ali Akbar Abbasian Arani and Reza Moradi

Using turbulators, obstacles, ribs, corrugations, baffles and different tube geometry, and also various arrangements of these components have a noticeable effect on the shell and…

Abstract

Purpose

Using turbulators, obstacles, ribs, corrugations, baffles and different tube geometry, and also various arrangements of these components have a noticeable effect on the shell and tube heat exchangers (STHEs) thermal-hydraulic performance. This study aims to investigate non-Newtonian fluid flow characteristics and heat transfer features of water and carboxyl methyl cellulose (H2O 99.5%:0.5% CMC)-based Al2O3 nanofluid inside the STHE equipped with corrugated tubes and baffles using two-phase mixture model.

Design/methodology/approach

Five different corrugated tubes and two baffle shapes are studied numerically using finite volume method based on SIMPLEC algorithm using ANSYS-Fluent software.

Findings

Based on the obtained results, it is shown that for low-mass flow rates, the disk baffle (DB) has more heat transfer coefficient than that of segmental baffle (SB) configuration, while for mass flow rate more than 1 kg/s, using the SB leads to more heat transfer coefficient than that of DB configuration. Using the DB leads to higher thermal-hydraulic performance evaluation criteria (THPEC) than that of SB configuration in heat exchanger. The THPEC values are between 1.32 and 1.45.

Originality/value

Using inner, outer or inner/outer corrugations (outer circular rib and inner circular rib [OCR+ICR]) tubes for all mass flow rates can increase the THPEC significantly. Based on the present study, STHE with DB and OCR+ICR tubes configuration filled with water/CMC/Al2O3 with f = 1.5% and dnp = 100 nm is the optimum configuration. The value of THPEC in referred case was 1.73, while for outer corrugations and inner smooth, this value is between 1.34 and 1.57, and for outer smooth and inner corrugations, this value is between 1.33 and 1.52.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 11 February 2021

Houda Laabidi, Houda Jouini and Abdelkader Mami

The purpose of this paper is to propose an efficient current control technique based on model predictive control (MPC) for grid-connected wind conversion system. This nonlinear…

63

Abstract

Purpose

The purpose of this paper is to propose an efficient current control technique based on model predictive control (MPC) for grid-connected wind conversion system. This nonlinear strategy is applied for the chopper circuit and grid-tied inverter and compared with other two conventional schemes; a traditional proportional-integral (PI) and sliding mode controller (SMC) using the same switching frequency.

Design/methodology/approach

Firstly, the MPC scheme uses the mathematical model to predict future behaviors of the controlled converter outputs for possible switching states. After that, the optimal voltage vector is selected by minimizing a cost function, which is defined as a sum of the absolute values of the controlled current errors. Then, the corresponding switching signals are applied to the converter switches in the next sampling period to track correctly the reference current. Thus, the MPC scheme ensures a minimal error between the predicted and reference trajectories of the considered variables.

Findings

The MPC-based algorithm presents several benefits in terms of high accuracy control, reduced DC-link voltage ripples during steady-state operation, faster transient response, lower overshoots and disturbance rejection and acceptable total harmonic distortion.

Originality/value

The authors introduce several simulation case studies, using PSIM software package, which prove the reliability and effectiveness of the proposed MPC scheme. Therefore, the MPC performances, during dynamic and steady-state condition, are compared with those obtained by a PI regulator and SMC to highlight the improvements, specifically the transfer of smooth power to the grid.

Article
Publication date: 1 December 2020

Seyed Saeed Mazloomy Mahmoodabad, Ali Akbar Vaezi, Tahere Soltani, Azadeh Nadjarzadeh, Seyedeh Mahdieh Namayandeh, Mohammad Hossein Soltani and Hossien Fallahzadeh

Increased dietary salt content is one of the effective factors of hypertension and a major public health challenge globally. Although the positive effects of dietary salt…

Abstract

Purpose

Increased dietary salt content is one of the effective factors of hypertension and a major public health challenge globally. Although the positive effects of dietary salt reduction on health are universally accepted, people can hardly reduce their salt intake. The purpose of this study is to identify the inhibitory factors of dietary salt reduction among 20–65-year-old women in Yazd City, Iran.

Design/methodology/approach

This study was conducted using a deductive content analysis approach based on the communication for the behavioral impact (COMBI) framework. The purposeful sampling method was applied with maximum variation in terms of different educational levels, age groups, occupational status and residential areas to select the participants. Snowball sampling was used to select health-care professionals. Furthermore, semi-structured interviews and focus-group discussions were conducted with 31 local women and 11 health-care professionals working in the City until data saturation was achieved. Data were analyzed using Graneheim and Landsman’s method.

Findings

After data analysis, 617 initial codes were extracted over the perceived barriers. After merging similar codes, 223 codes were extracted. The barriers were classified into five main categories of family, personal, organizational, educational and socio-cultural barriers.

Originality/value

Based on the COMBI framework, the results demonstrated that the most important barriers for reducing salt intake were negative attitude toward restrictions on dietary salt intake, insufficient and incorrect beliefs about the health risk of salt, lack of family support, inadequate health literacy and low self-efficacy in Yazd City. Among these barriers, lack of family support was considered as the most effective factor in reducing salt consumption. So, by focusing on this area and providing the community with the required education, the amount of salt consumed by families can be reduced.

Details

International Journal of Human Rights in Healthcare, vol. 13 no. 5
Type: Research Article
ISSN: 2056-4902

Keywords

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