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Construction materials comprise a major part of the total construction cost. Given the importance of bitumen as a fundamental material in construction projects, it is imperative to have an accurate forecast of its consumption in the planning and material sourcing phases on the project. This study aims to introduce a flexible genetic algorithm-fuzzy regression approach for forecasting the future bitumen consumption.

In the proposed approach, the parameter tuning process is performed on all parameters of genetic algorithm (GA), and the finest coefficients with minimum errors are identified. Moreover, the fuzzy regression (FR) model is used for estimation. Analysis of variance (ANOVA) is used for selecting among GA, FR or conventional regression (CR). To show the applicability of the proposed approach, Iran’s bitumen consumption data in the period of 1991-2006 are used as a case study.

Production, import, export, road construction and price are considered as the input data used in the present study. It was concluded that, among all the forecasting methods used in this study, GA was the best method for estimating.

The proposed approach outperforms the conventional forecasting methods for the case of bitumen which is a fundamental economic ingredient in road construction projects. This approach is flexible, in terms of amount and uncertainty of the input data, and can be easily adapted for forecasting other materials and in different construction projects. It can have important implications for the managers and policy makers in the construction market where accurate estimation of the raw material demand is crucial.

This is the first in this field introducing a flexible GA-FR approach for improving bitumen consumption estimation in the construction literature. The proposed approach’s significance has two folds. Firstly, it is completely flexible. Secondly, it uses CRs as an alternative approach for estimation because of its dynamic structure.

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.

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

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.

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.

Silicone softeners are widely used in the textile industry to improve the performance of textile products. The thermal characteristics and flammability of polyester fabrics can be influenced by these compounds, which need to be considered, as important issues of human safety. The purpose of this paper is to investigate the changes induced on the polyester fibre by silicone softener treatment using a pad/dry/cure method.

The fibres were first treated with nano‐ and microemulsion silicone softeners. The influence of the silicone emulsion type on thermal properties and flammability of the resultant samples were investigated by various analytical techniques, namely, the differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), dynamical mechanical thermal analysis (DMTA) and horizontal flammability test (HFT).

Results showed that the silicone softeners increase the thermal degradation and flammability of the polyethylene terephthalate (PET) substrate.

The paper's study of thermal and flammability of the silicone‐treated sample is novel and can be used to optimize the properties of silicone polymers during production and consumption.

Since the election of June 2009, the Islamic Republic of Iran has witnessed a huge crisis with the outburst of street protests and demonstrations, challenging its validity. Indeed, it has been so intense that it has shaken the whole Islamic Republic for the first time since the 1979 Iranian revolution. What has happened since the disputed election was an upheaval few had anticipated, an opening of Pandora's box, with millions daring to question the, Velayate Fagih, the most important constituent of the Islamic Republic. This postelection period has created a “revolutionary”’ potential that has so far been met with repressive force and violence on the part of the ruling elites leaving no leverage for compromise. Of course, in the 30 years since the revolution, the Islamic Republic's power structures have faced factionalism. These recent developments demonstrate how deeply rooted run the contradictions and differences between the various groups. This upheaval has thrown all sorts of questions into the air: could Iran remain as a Republic? Or would Iran turn into a God's Kingdom, ever more dictatorial in its approach? Or would the splits within the ruling elites continue to crack the fabric of the regime? Will there be a similar schism to that which took place during the Constitutional Revolution in the early 20th century when a leading member of the clergy, Noori, was finally hanged in July 1909 for being openly against reform? Finally, what is the possibility of change beyond the Islamic Republic in Iran?

Data envelopment analysis (DEA) is a non-parametric model that is developed for evaluating the relative efficiency of a set of homogeneous decision-making units that each unit transforms multiple inputs into multiple outputs. However, usually the decision-making units are not completely similar. The purpose of this paper is to propose an algorithm for DEA applications when considered DMUs are non-homogeneous.

To reach this aim, an algorithm is designed to mitigate the impact of heterogeneity on efficiency evaluation. Using fuzzy C-means algorithm, a fuzzy clustering is obtained for DMUs based on their inputs and outputs. Then, the fuzzy C-means based DEA approach is used for finding the efficiency of DMUs in different clusters. Finally, the different efficiencies of each DMU are aggregated based on the membership values of DMUs in clusters.

Heterogeneity causes some positive impact on some DMUs while it has negative impact on other ones. The proposed method mitigates this undesirable impact and a different distribution of efficiency score is obtained that neglects this unintended impacts.

The proposed method can be applied in DEA applications with a large number of DMUs in different situations, where some of them enjoyed the good environmental conditions, while others suffered from bad conditions. Therefore, a better assessment of real performance can be obtained.

The paper proposed a hybrid algorithm combination of fuzzy C-means clustering method with classic DEA models for the first time.

This paper aims to present an account and discussion of Imam Ali’s view on poverty and socio-economic justice. The concept of socio-economic justice is of utmost importance in Islamic teachings.

This exercise is based on examining Nahj al-Balagha, a tenth century collection of sermons and letters of Imam Ali Ibn Abutalib.

First, in Imam Ali’s view, socially just outcomes can only be achieved through just means and procedures. Second, acute and visible inequalities and side-by-side co-existence of extreme wealth and poverty in a society point to the existence of socio-economic injustices. Third, a society that is suffering from severe and continuous socio-economic injustices or, in other words, acute poverty and inequality will cease to prosper and develop. Fourth, the main objective of an Islamic governance system is to adopt policies, institutions and procedures that would reduce or eliminate socio-economic injustices. A government that fails to reduce socio-economic injustices, in Imam Ali’s view, has failed in its main mission of protecting the rights of the public and ensuring their prosperity. Finally, regardless of government action or inaction, each individual in a society is also responsible to reduce socio-economic injustices to the best of his/her knowledge and ability.

This paper aims to present the first comprehensive account of Imam Ali’s view on poverty and socio-economic justice and it could prove to be practically useful to modern Muslims and non-Muslims alike, whatever their position in society.

The purpose of this paper is to conduct a structured review of the literature on the factors affecting the strategic thinking of an organization. This study offers some theoretical insights by analysing the divergent or analogous views of authors on these factors by analysing the empirical studies carried out in the literature.

An empirical method of conducting a structured literature review has been adopted in this study. Theory context characteristic methodology framework and meta-analysis are the methodologies applied to analyse the different empirical studies conducted in the literature and determine the variation or similarities in the views of authors over the same factor based on their effect sizes. This study analyses over 45 different empirical studies in the literature conducted on the factors affecting strategic thinking.

This study explains how the factors have been similarly or differently explained by the authors in the literature. This analysis gives a better understanding of the factors affecting strategic thinking and quantitatively amalgamates the current empirical studies carried out in the literature. The effects sizes generated for each factor helps in determining the homogeneous or heterogeneous nature of the factor.

The study is limited only to analyse the homogeneity or heterogeneity of the factors affecting strategic thinking at an organisational level. This study can be further extended by analysing the type of effect these factors have on the strategic thinking of the organisation.

The findings of this study identify the homogeneity or heterogeneity of the factors affecting strategic thinking in an organisation. This helps the top management to concentrate on these factors, which might develop a strategic thinking nature in the organisation, leading to the better formation of strategies, and successfully implement them in their businesses.

The study fills the unattended gaps in the literature by analysing the homogeneous and heterogeneous nature of the factors affecting the strategic thinking of an organisation.