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Article
Publication date: 6 May 2020

Saeed Akbari, Farzad Pour Rahimian, Moslem Sheikhkhoshkar, Saeed Banihashemi and Mostafa Khanzadi

Successful implementation of infrastructure projects has been a controversial issue in recent years, particularly in developing countries. This study aims to propose a decision…

282

Abstract

Purpose

Successful implementation of infrastructure projects has been a controversial issue in recent years, particularly in developing countries. This study aims to propose a decision support system (DSS) for the evaluation and prediction of project success while considering sustainability criteria.

Design/methodology/approach

To predict sustainable success factor, the study first developed its sustainable success factors and sustainable success criteria. These then formed a decision table. A rough set theory (RST) was then implemented for rules generation. The decision table was used as the input for the rough set, which returned a set of rules as the output. The generated rulesets were then filtered in fuzzy inference system (FIS), before serving as the basis for the DSS. The developed prediction tool was tested and validated by applying data from a real infrastructure project.

Findings

The results show that the developed rough set fuzzy method has strong ability in evaluation and prediction of the project success. Hence, the efficacy of the DSS is greatly related to the rule-based system, which applies RST to generate the rules and the result of the FIS was found to be valid via running a case study.

Originality/value

Use of DSS for predicting the sustainable success of the construction projects is gaining progressive interest. Integration of RST and FIS has also been advocated by the seminal literature in terms of developing robust rulesets for impeccable prediction. However, there is no preceding study adopting this integration for predicting project success from the sustainability perspective. The developed system in this study can serve as a tool to assist the decision-makers to dynamically evaluate and predict the success of their own projects based on different sustainability criteria throughout the project life cycle.

Details

Construction Innovation , vol. 20 no. 4
Type: Research Article
ISSN: 1471-4175

Keywords

Available. Open Access. Open Access
Article
Publication date: 21 May 2018

Saeed Akbari, Mostafa Khanzadi and Mohammad Reza Gholamian

To address requirements and specifications of construction project, academics need to build a project classification model. In recent years, project success concept, particularly…

3114

Abstract

Purpose

To address requirements and specifications of construction project, academics need to build a project classification model. In recent years, project success concept, particularly on large-scale construction projects, has been a controversial issue, especially in developing countries. Hence, in this paper, after introducing a sustainable success index (SSI), a novel method called “rough set approach” had been adopted to induce decision rules and to classify construction projects. The paper aims to discuss these issues.

Design/methodology/approach

At first, 20 effective success factors and 15 success criteria based on three pillars of sustainability of economy, society and environment had been categorized. The research data used for analysis had been collected from 26 large-scale construction projects in Iran and five other countries. After collecting data collection, observations had been analyzed and 51 decision rules were generated, and the projects were classified. Eventually, in order to evaluate the performance of the generated rules, confusion matrix was applied, and the model was validated.

Findings

The results of the present study show that rough set theory (RST) can be an effective and valuable tool for building expert systems. Practical applications of these results along with limitations and future research are described.

Originality/value

Perhaps for the first time, in the present study, a number of large-scale construction projects are classified based on SSI. Applying RST for building rule-based system and classifying projects in construction project area are novel attempts undertaken in this paper. The rules induced in this study can be applied to develop a sustainable success prediction model in the future studies.

Details

Engineering, Construction and Architectural Management, vol. 25 no. 4
Type: Research Article
ISSN: 0969-9988

Keywords

Available. Content available
Article
Publication date: 2 August 2021

Modupeola Dada, Patricia Popoola and Ntombi Mathe

This study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential…

2164

Abstract

Purpose

This study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential alternatives to nickel superalloys for gas turbine applications. Understandings of the laser surface modification techniques of the HEA are discussed whilst future recommendations and remedies to manufacturing challenges via laser are outlined.

Design/methodology/approach

Materials used for high-pressure gas turbine engine applications must be able to withstand severe environmentally induced degradation, mechanical, thermal loads and general extreme conditions caused by hot corrosive gases, high-temperature oxidation and stress. Over the years, Nickel-based superalloys with elevated temperature rupture and creep resistance, excellent lifetime expectancy and solution strengthening L12 and γ´ precipitate used for turbine engine applications. However, the superalloy’s density, low creep strength, poor thermal conductivity, difficulty in machining and low fatigue resistance demands the innovation of new advanced materials.

Findings

HEAs is one of the most frequently investigated advanced materials, attributed to their configurational complexity and properties reported to exceed conventional materials. Thus, owing to their characteristic feature of the high entropy effect, several other materials have emerged to become potential solutions for several functional and structural applications in the aerospace industry. In a previous study, research contributions show that defects are associated with conventional manufacturing processes of HEAs; therefore, this study investigates new advances in the laser-based manufacturing and surface modification techniques of HEA.

Research limitations/implications

The AlxCoCrCuFeNi HEA system, particularly the Al0.5CoCrCuFeNi HEA has been extensively studied, attributed to its mechanical and physical properties exceeding that of pure metals for aerospace turbine engine applications and the advances in the fabrication and surface modification processes of the alloy was outlined to show the latest developments focusing only on laser-based manufacturing processing due to its many advantages.

Originality/value

It is evident that high entropy materials are a potential innovative alternative to conventional superalloys for turbine engine applications via laser additive manufacturing.

Details

World Journal of Engineering, vol. 20 no. 1
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 2 January 2018

Ali Yousefi, Saeed Amir Aslanzadeh and Jafar Akbari

The purpose of this paper is to investigate the surface properties, particle sizes and corrosion inhibition performance of sodium dodecyl sulfate (SDS) in the presence of…

279

Abstract

Purpose

The purpose of this paper is to investigate the surface properties, particle sizes and corrosion inhibition performance of sodium dodecyl sulfate (SDS) in the presence of imidazolium-based ionic liquid as an additive. Up to now, different properties of alone surfactants and ionic liquids have been studied. However, few studies have been devoted to mixed ionic liquid and surfactant. The significance and novelty of this research is the investigation of 1-methylimidazolium trinitrophenoxide ([MIm][TNP]) as ionic liquid effects on SDS corrosion behavior.

Design/methodology/approach

The inhibition effect of [MIm][TNP], SDS and their mixtures on mild steel surface in 2 M hydrochloric acid (HCl) solution was examined by electrochemical impedance spectroscopy, potentiodynamic polarization (PDP), scanning electron microscopy (SEM), atomic force microscopy and quantum chemical calculations as well as dynamic light scattering (DLS) and surface tension measurements to discuss surface properties of studied solutions.

Findings

Based on the results, ionic liquid/SDS mixtures significantly indicated better inhibition properties than pure surfactant solution. PDP curves indicated that the studied compounds act as mixed-type of inhibitors. The critical micelle concentration, surface properties and particle sizes were investigated from the surface tension measurements and DLS results.

Originality/value

Adsorption of the inhibitors on the steel surface obeyed the Villamil adsorption model. SEM was used for surface analysis and verified the inhibition efficiency of mixed IL/SDS system. Quantum chemical calculations were performed using density functional theory, and a good relationship between experimental and theoretical data has been obtained.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 12 June 2017

Saeed Bakhtiyari, Leila Taghi Akbari and Masoud Jamali Ashtiani

The purpose of this study is assessment of fire and smoke hazards of some fiber reinforced polymers (FRP). The use of FRP strengthening strips has been found rapid growth in…

173

Abstract

Purpose

The purpose of this study is assessment of fire and smoke hazards of some fiber reinforced polymers (FRP). The use of FRP strengthening strips has been found rapid growth in construction industry of Iran and many other countries. However, the fire and smoke hazards of these materials in both construction and use phases need to be determined and the appropriated measures against fire should be taken.

Design/methodology/approach

The fire hazards of two types of fibre-reinforced epoxy composites (graphite fibre-reinforced polymer and carbon fibre-reinforced polymer) were investigated in bench-scale using cone calorimeter test method. Time to ignition, heat release rate, total heat release, smoke release and carbon monoxide production were measured and analysed. Time to flashover of an assumed room lined with the tested FRP was analysed with Conetools software. Smoke production and toxicity of the considered composites were also analysed and discussed, using the fractional effective dose parameter.

Findings

The results showed that the tested FRP products had a high fire hazard and a potential high contribution to fire growth. The tests also proved that the used epoxy resin had a low glass transition temperature, around 50°C; therefore, the mechanical strength of the product could be drastically reduced at first stages of a probable fire incident. This also showed that a regular thermal barrier, typically used for protection of plastic foams against fire, could not be sufficient for the protection of strengthening FRP composites.

Originality/value

This research was carried out for the first time for the materials used in construction industry of Iran. The results and achievements were very useful for safe use and development of proper details of application of the system.

Details

International Journal of Disaster Resilience in the Built Environment, vol. 8 no. 3
Type: Research Article
ISSN: 1759-5908

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Article
Publication date: 12 June 2017

Saeed Bakhtiyari, Arsalan Kalali, Leila Taghi Akbari and Farhang Farahbod

This paper aims to evaluate fire resistance of carbon fiber-reinforced polymer (CFRP)-strengthened concrete slabs in two forms of unprotected and protected against fire.

174

Abstract

Purpose

This paper aims to evaluate fire resistance of carbon fiber-reinforced polymer (CFRP)-strengthened concrete slabs in two forms of unprotected and protected against fire.

Design/methodology/approach

To achieve the objective, an unstrengthened and two CFRP-strengthened concrete slabs were first subjected to increasing gravity loading until failure. Subsequently, the unstrengthened concrete slab was placed on a furnace and was subjected to a constant service gravity load and then, the temperature of the furnace was increased according to a standard temperature–time curve until the failure of the slab occurred. This slab was strengthened by CFRP with two different amounts and then, in two cases of unprotected and protected against fire, was tested in accordance with the aforementioned method.

Findings

The gravity test results revealed that CFRP strips bonded to concrete slabs increased the load-bearing capacity considerably. So, this method can be suitable for flexural strengthening of concrete slabs. The fire test results showed that because of more load-bearing capacity and subsequently increase in service gravity load, the strengthened concrete slab failed in a short time due to the lack of CFRP resistance against fire. By contrast, the protected specimens resisted the fire in a considerable time. In addition, it was revealed that details of fire protective coating had an important effect on fire resistance duration.

Originality/value

It is notable that in the literature, there is a lack of data on the fire endurance of fiber-reinforced polymer-strengthened concrete slabs alone without any fire protection system. Furthermore, the applicability and effectiveness of a new kind of spray mineral fire protective coatings was evaluated.

Details

International Journal of Disaster Resilience in the Built Environment, vol. 8 no. 3
Type: Research Article
ISSN: 1759-5908

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Article
Publication date: 22 March 2024

Mohammad Dehghan Afifi, Bahram Jalili, Amirmohammad Mirzaei, Payam Jalili and Davood Ganji

This study aims to analyze the two-dimensional ferrofluid flow in porous media. The effects of changes in parameters such as permeability parameter, buoyancy parameter, Reynolds…

86

Abstract

Purpose

This study aims to analyze the two-dimensional ferrofluid flow in porous media. The effects of changes in parameters such as permeability parameter, buoyancy parameter, Reynolds and Prandtl numbers, radiation parameter, velocity slip parameter, energy dissipation parameter and viscosity parameter on the velocity and temperature profile are displayed numerically and graphically.

Design/methodology/approach

By using simplification, nonlinear differential equations are converted into ordinary nonlinear equations. Modeling is done in the Cartesian coordinate system. The finite element method (FEM) and the Akbari-Ganji method (AGM) are used to solve the present problem. The finite element model determines each parameter’s effect on the fluid’s velocity and temperature.

Findings

The results show that if the viscosity parameter increases, the temperature of the fluid increases, but the velocity of the fluid decreases. As can be seen in the figures, by increasing the permeability parameter, a reduction in velocity and an enhancement in fluid temperature are observed. When the Reynolds number increases, an increase in fluid velocity and temperature is observed. If the speed slip parameter increases, the speed decreases, and as the energy dissipation parameter increases, the temperature also increases.

Originality/value

When considering factors like thermal conductivity and variable viscosity in this context, they can significantly impact velocity slippage conditions. The primary objective of the present study is to assess the influence of thermal conductivity parameters and variable viscosity within a porous medium on ferrofluid behavior. This particular flow configuration is chosen due to the essential role of ferrofluids and their extensive use in engineering, industry and medicine.

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Article
Publication date: 9 September 2013

Mamta Tandon, Padma Vasudevan, S.N. Naik and Philip Davies

A variety of biomass plantations are being raised for energy production. This case study is on energy production potential of seasonal oil bearing crops in India. These crops have…

498

Abstract

Purpose

A variety of biomass plantations are being raised for energy production. This case study is on energy production potential of seasonal oil bearing crops in India. These crops have the advantage of producing oil (liquid fuel) as well as biomass as agro residue (solid fuel). The purpose of the study is to estimate total energy yields of oil bearing crops and compare with other types of energy plantations. Also oil bearing crops bioaccumulate metals and thus phytoremediate soil. This provides scope for waste water irrigation.

Design/methodology/approach

Relevant published papers on energy production by raising oil bearing crops have been analyzed. The effect of waste water irrigation and agronomic practices on increasing productivity is given special attention.

Findings

It is shown that the seasonal oil bearing crops such as castor have a high potential to generate energy and this is comparable to energy produced by many perennial grasses. The energy yields of castor under irrigated condition was 196×103 MJ/ha and this is comparable to the reed canary grass which yields 195×103 MJ/ha. Some of the oil bearing crops are also super accumulators of certain toxic metals.

Research limitations/implications

In this study, only all the accessible papers on the topic could be analyzed.

Practical implications

This case study indicates that raising oil bearing crops such as castor using waste water has many advantages which include high energy yields, utilization of waste water for productive purpose and phytoremediation of soil.

Originality/value

The comparison made between various types of energy crops for their energy generation is an original contribution. Findings of economic and environmental benefits by waste water irrigation are also of value.

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Article
Publication date: 20 June 2016

Mohammad Riahi, Mohammad Sedighi and Hassan Rahmanian

The paper aims to design a process to mechanize traditional chasing and repoussé which is the art of creating an artistic pattern on a sheet metal by making high and low points…

167

Abstract

Purpose

The paper aims to design a process to mechanize traditional chasing and repoussé which is the art of creating an artistic pattern on a sheet metal by making high and low points through utilization of hammer and chisel. In scientific literature, it is a kind of incremental sheet metal forming.

Design/methodology/approach

In the designed process, a magnetic actuator is used as a hammer which converts electric energy into kinetic reciprocal impact energy, and hammering sequence is completely controlled via the designed software. The sheet is bound not to move easily. Then, a hammering mechanism is connected to the numerical control machine. As the magnetic hammer is moved gradually along the defined path, the sheet is chased gradually by controlling the consecutive impacts. Different methods of test sheet entanglement are also discussed to reduce noise and undesired deformations of sheet, and indents are also clarified.

Findings

The designed mechanism enables the user to form desired art patterns faster with more precision via the automated process. The hammering sequence is controlled via computer successfully. The designed magnetic actuator could be commercialized easily. Experiments show that the pitch under sheet is the best. Typical art patterns are chased successfully.

Originality/value

In incremental sheet metal punching, there was no control on hammering sequence before. In this process, the designed magnetic hammer is quite controllable. Also, it is easily attached to the computerized numerical control (CNC) and is suitable for commercial use. Furthermore, the stuff under sheet was not taken into consideration before.

Details

Rapid Prototyping Journal, vol. 22 no. 4
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 11 June 2020

Morteza Akbari, Afsaneh Bagheri, Saheb Imani and Mohammad Asadnezhad

The crucial importance of innovation leadership for high technology small and medium-size enterprises (SMEs) has been suggested in the literature. However, few studies empirically…

4162

Abstract

Purpose

The crucial importance of innovation leadership for high technology small and medium-size enterprises (SMEs) has been suggested in the literature. However, few studies empirically examined the impact of leadership style on innovation work behavior (IWB) of employees in the context of SMEs. Furthermore, our knowledge is limited about how leaders of high technology SMEs influence the IWB of their employees. The present study explores the effect of entrepreneurial leadership on IWB of employees and introduces creative self-efficacy and support for innovation as the mechanisms through which the leaders encourage their employees' IWB in information and communications technology (ICT) SMEs in Iran.

Design/methodology/approach

The sample was selected from high technology ICT SMEs using the simple random sampling method and included 175 CEOs and owner-managers of the businesses. We used validated questionnaires to test the hypothesized relationships between entrepreneurial leadership, IWB, creative self-efficacy and support for innovation.

Findings

The findings show that entrepreneurial leadership has a significant and positive impact on IWB of employees in ICT SMEs. Furthermore, employees’ creative self-efficacy and leaders’ support for innovation mediate the relationship between entrepreneurial leadership and IWB. Implications of the results and suggestions for developing IWB among the employees of high technology SMEs are suggested.

Originality/value

The study makes important contributions to both entrepreneurial leadership and the innovation behavior literature and theory development specifically in high technology SMEs in the transitioning economy of Iran. The findings also contribute to the existing empirical studies on how entrepreneurial leadership affects IWB of employees by examining the mediating role of creative self-efficacy and support for innovation and in the settings of ICT high technology SMEs.

Details

European Journal of Innovation Management, vol. 24 no. 1
Type: Research Article
ISSN: 1460-1060

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