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1 – 10 of 32
Article
Publication date: 12 October 2020

Ali Kaveh, Hossein Akbari and Seyed Milad Hosseini

This paper aims to present a new physically inspired meta-heuristic algorithm, which is called Plasma Generation Optimization (PGO). To evaluate the performance and capability of…

Abstract

Purpose

This paper aims to present a new physically inspired meta-heuristic algorithm, which is called Plasma Generation Optimization (PGO). To evaluate the performance and capability of the proposed method in comparison to other optimization methods, two sets of test problems consisting of 13 constrained benchmark functions and 6 benchmark trusses are investigated numerically. The results indicate that the performance of the proposed method is competitive with other considered state-of-the-art optimization methods.

Design/methodology/approach

In this paper, a new physically-based metaheuristic algorithm called plasma generation optimization (PGO) algorithm is developed for solving constrained optimization problems. PGO is a population-based optimizer inspired by the process of plasma generation. In the proposed algorithm, each agent is considered as an electron. Movement of electrons and changing their energy levels are based on simulating excitation, de-excitation and ionization processes occurring through the plasma generation. In the proposed PGO, the global optimum is obtained when plasma is generated with the highest degree of ionization.

Findings

A new physically-based metaheuristic algorithm called the PGO algorithm is developed that is inspired from the process of plasma generation.

Originality/value

The results indicate that the performance of the proposed method is competitive with other state-of-the-art methods.

Details

Engineering Computations, vol. 38 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 9 August 2022

Behnam (Abdolreza) Oboudi, Alireza Elahi, Hossein Akbari Yazdi and Do Young Pyun

In recent years, neurophysiological tools have been vastly applied in sport marketing research. Eye tracking, a pervasive sensor technology, has received a growing interest to…

Abstract

Purpose

In recent years, neurophysiological tools have been vastly applied in sport marketing research. Eye tracking, a pervasive sensor technology, has received a growing interest to examine the effects of advertising through sport on viewer attention. While there is a plethora of evidence in advertising that supports the positive effects of various advertising types and locations on viewer attention in various sport contexts, little is known about the role of a prosocial overlay ad on viewer attention when watching televised football matches. Therefore, this research aims to examine the differences in viewers' attention (i.e. fixation and duration) with regard to game attractiveness and colors of the prosocial message during televised football matches.

Design/methodology/approach

To identify the research gap, the authors first reviewed the relevant sport marketing and neuroscience research on advertising effectiveness. The authors selected a prosocial message displayed. Adopting an experimental research design and using eye tracking, this study examined the impacts of game attractiveness and colors of message on viewer attention to the prosocial message displayed on an overlay advertisement during a football match.

Findings

The authors found that the colors of prosocial messages and game attractiveness had significant effects on viewer attention to the prosocial message.

Originality/value

In this study, the authors sought to add advertisement color, as well as game attractiveness, to the extant knowledge in marketing literature as effective advertising factors in capturing viewers' attention. These variables can offer marketers new insights in designing effective advertisements for the context of televised sports events in a specialized field.

Details

Sport, Business and Management: An International Journal, vol. 13 no. 2
Type: Research Article
ISSN: 2042-678X

Keywords

Article
Publication date: 3 March 2023

Reza Hafezi, Hossein Heirani, Mohammadreza Akbari, Ahmad Mortezaee, Naser Bagherimoghaddam, Hamid Heydari and Amirhossein Souhankar

In the case of Iran, about 19 years have passed since the announcement of general energy policies. Policies adopted in the past included too many approaches and goals for the…

Abstract

Purpose

In the case of Iran, about 19 years have passed since the announcement of general energy policies. Policies adopted in the past included too many approaches and goals for the energy sector that some of them are in conflict with each other and their simultaneous implementation was impossible. Therefore, many of the expected goals of these policies have not been achieved. It is very important to adopt an appropriate approach that is compatible with the country’s characteristics and can steer energy policies. Therefore, this study aims to adopt an appropriate approach for the country’s energy sector according to the conditions and needs of the country.

Design/methodology/approach

A participatory scenario technique is designed and used to develop plausible projections in the case of Iran’s energy futures. Based on the proposed methodology, the research process starts with data gathering through interviews and national plans analysis. Then, findings were used as inputs to a simulation-based scenario development process. Scenarios are developed based on Monte Carlo simulation via cross-impact analysis technique purified based on expert judgments.

Findings

In this paper, to recognize Iran’s general approach to energy in the next 20 years, driving forces of change were introduced and used as input for the scenario development phase. Results showed sanctions play a significant role in Iran’s energy future and determine the directions of other driving forces. For renewable energy, it was proposed to increase the renewable share in Iran’s electricity generation mix to 5% of the total installed capacity. In the case of fossil fuel extraction, the maximum efficient rate was proposed for both oil and natural gas national production strategy.

Originality/value

This research is novel both in terms of application and theory. A new participatory scenario development method is used using simulations that are equipped based on experts’ judgments. Also from the practical perspective, this research targeted a future-oriented challenging problem to initialize national policy in a resource-rich developing economy (i.e. Iran).

Details

foresight, vol. 25 no. 5
Type: Research Article
ISSN: 1463-6689

Keywords

Article
Publication date: 13 November 2020

Zahra Fozouni Ardekani, Morteza Akbari, Giovanni Pino, Miguel Ángel Zúñiga and Hossein Azadi

This study investigates consumers' willingness to adopt genetically modified foods (GM) and the role of innovation and behavioral determinants.

Abstract

Purpose

This study investigates consumers' willingness to adopt genetically modified foods (GM) and the role of innovation and behavioral determinants.

Design/methodology/approach

A new integrated model that expands the Health Belief Model (HBM) into the Innovation Diffusion Theory (IDT) was developed and examined. A total of 241 consumers were selected from the capital of Iran, Tehran, through a multistage random sampling. The data were analyzed using SEM-PLS modeling.

Findings

The extended HBM model was able to predict about 84% of the variance changes in consumers' willingness to adopt GM foods. The effects of net benefit and perceived compatibility on the willingness were also significant. In addition, the mediating effect of compatibility on the relationship between net benefit/self-efficacy and willingness to adopt GM foods was also significant.

Originality/value

This study contributes to the literature by developing the HBM into the IDT to assess consumers' willingness to adopt GM foods.

Details

British Food Journal, vol. 123 no. 3
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 3 April 2007

S. Rahmati, J. Akbari and E. Barati

Dimensional accuracy analysis of wax model created by room temperature vulcanization (RTV) silicone rubber molding to be used in investment casting is presented. The purpose of…

1271

Abstract

Purpose

Dimensional accuracy analysis of wax model created by room temperature vulcanization (RTV) silicone rubber molding to be used in investment casting is presented. The purpose of this paper is to discuss the effective parameters of dimensional accuracy in RTV tooling technique.

Design/methodology/approach

After producing a pattern by stereolithography (SLA) and then creating the RTV silicone rubber mold by the SLA pattern, dimensional accuracy of wax models produced by RTV tool are analyzed. Design of experiments (DOE) using the Taguchi approach is used for analysis and determination of optimum condition.

Findings

Experiments show that the dimensional accuracy in RTV technique is as accurate as in traditional molding. Hence, RTV tooling technique can be used in investment casting. Using Taguchi approach based on DOE, it was realized that the optimum condition to achieve acceptable accuracy is 35°C for mold temperature, 85°C for wax temperature, and −0.5 barG for vacuum pressure.

Practical implications

RTV silicone rubber mold is a useful alternative of metallic mold to produce wax patterns for investment casting. It has benefits such as reduction in production lead‐time and cost, compared with traditional metallic mold.

Originality/value

A case study for research of dimensional accuracy of wax patterns created by RTV silicone rubber mold had not been attempted as such. In addition to reduction in production lead‐time and cost, the dimensional accuracy of wax patterns using RTV tooling technique are as accurate as in traditional technique.

Details

Rapid Prototyping Journal, vol. 13 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 4 December 2018

Marjan Goodarzi, Saeed Javid, Ali Sajadifar, Mehdi Nojoomizadeh, Seyed Hossein Motaharipour, Quang-Vu Bach and Arash Karimipour

With respect to two new subjects, i.e. nanofluids and microchannels, in heat transfer systems and modern techniques used for building them, this paper aims to study on effect of…

Abstract

Purpose

With respect to two new subjects, i.e. nanofluids and microchannels, in heat transfer systems and modern techniques used for building them, this paper aims to study on effect of using aluminum oxide nanoparticles in non-Newtonian fluid of aqueous solution of carboxy-methyl cellulose in microtube and through application of different slip coefficients to achieve various qualities on surface of microtube.

Design/methodology/approach

Simultaneously, the effect of presence of nanoparticles and phenomenon of slip and temperature jump has been explored in non-Newtonian nanofluid in this essay. The assumption of homogeneity of nanofluid and fixed temperature of wall in microtube has been used in modeling processes.

Findings

The results have been presented as diagrams of velocity, temperature and Nusselt Number and the investigations have indicated that addition of nanoparticles to the base fluid and increase in microtube slip coefficient might improve rate of heat transfer in microtube.

Originality/value

The flow of non-Newtonian nanofluid of aqueous solution of carboxy methyl cellulose-aluminum oxide has been determined in a microtube for the first time.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 25 January 2019

Davood Toghraie, Ramin Mashayekhi, Hossein Arasteh, Salman Sheykhi, Mohammadreza Niknejadi and Ali J. Chamkha

This is a 3D numerical study of convective heat transfer through a micro concentric annulus governing non-uniform heat flux boundary conditions employing water-Al2O3 nanofluid…

Abstract

Purpose

This is a 3D numerical study of convective heat transfer through a micro concentric annulus governing non-uniform heat flux boundary conditions employing water-Al2O3 nanofluid. The nanofluid is modeled using two-phase mixture model, as it has a good agreement to experimental results.

Design/methodology/approach

Half of the inner pipe surface area of the annulus section of a double pipe heat exchanger is exposed to a constant heat flux which two models are considered to divide the exposing surface area to smaller ones considering the fact that in all cases half of the inner pipe surface area has to be exposed to the heat flux: in model (A), the exposing surface area is divided radially to two parts (A1), four parts (A2) and eight parts (A3) by covering the whole length of the annulus and in model (B) the exposing surface area is divided axially to two parts (B1), four parts (B2) and eight parts (B3) by covering half of the annulus radially.

Findings

The results reveal that model (B) leads to higher Nusselt numbers compared to model (A); however, at Reynolds number 10, model (A3) exceeds model (B3). The average Nusselt number is increased up to 142 and 83 per cent at models (A3) with Reynolds number 10 and model (B3) with Reynolds number 1000, respectively.

Originality/value

This paper is a two-phase investigation of water-Al2O3 nanofluid in a micro concentric annulus under non-uniform heat flux boundary conditions.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 December 2020

Goudarz Alibakhshi, Hossein Abdollahi and Behzad Nezakatgoo

This study aimed at exploring the antecedents of English as a Foreign Language (EFL) teachers' self-efficacy (SE). That is, the main purpose was to deeply delve into the main…

Abstract

Purpose

This study aimed at exploring the antecedents of English as a Foreign Language (EFL) teachers' self-efficacy (SE). That is, the main purpose was to deeply delve into the main variables and latent which lead to a high sense of SE among teachers of English as a foreign language.

Design/methodology/approach

A phenomenological inquiry was employed to explore the antecedents of language teachers from their eyes. In this study, the phenomenon is SE antecedents. The researchers employed this method to help identify the meaning behind the human experience as it is related to a phenomenon or notable collective occurrence. A semistructured interview checklist was developed, carefully worded, reviewed by five teacher educators known as experts in qualitative research methodology and teacher education and edited based on the experts' feedback

Findings

The findings showed that the antecedents of SE can be categorized into personal variables, educational variables and institutional variables. Personal variables include verbal intelligence, language proficiency and some other traits. The institutional variables include support from administration, support from colleagues, support from the community and quality of work life. The educational antecedents include preservice and in-service training courses. Preservice training courses included the following: the courses on general language skills, courses on teaching methods, practicum courses, etc.

Originality/value

This study was undertaken in a specific context and the participants are specific. Almost all studies on SE are quantitative, and this qualitative study explored the antecedents of teachers' SE from their own eyes. Some of the explored studies were not mentioned in any of the related studies.

Details

Qualitative Research Journal, vol. 21 no. 3
Type: Research Article
ISSN: 1443-9883

Keywords

Article
Publication date: 13 November 2017

Hakimeh Mostafavi, Mohammad Hossein Ziloochi, Sajad Delavari, Satar Rezaei and Enayatollah Homaie Rad

Mental health is one of the most important factors for evaluating the health of different age groups in the community. The most common forms of mental health disorders are…

Abstract

Purpose

Mental health is one of the most important factors for evaluating the health of different age groups in the community. The most common forms of mental health disorders are depression and anxiety. Health status of students as an important age group has positive consequences in the community. To provide special recommendations for preventing mental disorders, the purpose of this paper is to determine the correlations among the individualism and family orientation and mental health.

Design/methodology/approach

A meta-analysis was conducted to find scores of mental health. International databases of Scopus and PubMed as well as Iranian databases of IranMedex and SID were systematically searched in September 2014 for studies conducted on Iranian students. Of 379 reviewed studies, 58 were selected for meta-analysis. A meta-regression model was estimated to show the effects of individualism and family orientation on mental health.

Findings

Eight studies were conducted in Tehran. Eight studies were published in English. In nine studies, school students, and in one study both school and university students were surveyed. General Health Questionnaire-28 score varied from 13.77 in Arak to 47.78 in Tehran. The results of this study showed that the pooled mental health score for Iranian students was 23.725, indicating that Iranian students had poor mental health. In meta-regression, the coefficient of family orientation was −0.2893 and it was significant. Other variables did not have any significant relationship with mental health scores.

Originality/value

Improvement of living conditions and enabling the youth to positively communicate with different social groups are recommended.

Details

Mental Health and Social Inclusion, vol. 21 no. 5
Type: Research Article
ISSN: 2042-8308

Keywords

Article
Publication date: 11 May 2020

Seyed Sajad Sajadi, Saeed Reza Ostadzadeh and Seyed Hossein Hesamedin Sadeghi

The purpose of this paper is to investigate the simultaneous effects of ionization and dispersion of soil on the impulse behavior of grounding electrodes under first and…

Abstract

Purpose

The purpose of this paper is to investigate the simultaneous effects of ionization and dispersion of soil on the impulse behavior of grounding electrodes under first and subsequent stroke currents.

Design/methodology/approach

A recently introduced technique called improved multi-conductor transmission line (MTL) is simplified for grounding electrodes buried in both-affected soils.

Findings

The simulation results show that including the two effects simultaneously in highly resistive soils under high-valued subsequent stroke current is recommended. Otherwise, simultaneous effects can be disregard.

Originality/value

To the best of the authors’ knowledge, there is no research on sensitivity analyses for the simultaneous inclusion of the two effects on the effective length and the induced voltage on the soil surface. To this end, the simplified MTL is applied to the grounding electrodes. The simulation results show that the computational efficiency in comparison with previous methods is, first, considerably increased. Second, the simultaneous effects result in decreasing the soil surface voltage with respect to situations where either ionization or dispersion is taken into account (single-affected soils). In other words, the performance of grounding systems is improved. Third, the effective length in both-affected soil is has a middle value with respect to the single-affected soil. Such findings practically and financially are of importance.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 39 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

1 – 10 of 32