Sahar Tadayonirad, Hany Seidgar, Hamed Fazlollahtabar and Rasoul Shafaei
In real manufacturing systems, schedules are often disrupted with uncertainty factors such as random machine breakdown, random process time, random job arrivals or job…
Abstract
Purpose
In real manufacturing systems, schedules are often disrupted with uncertainty factors such as random machine breakdown, random process time, random job arrivals or job cancellations. This paper aims to investigate robust scheduling for a two-stage assembly flow shop scheduling with random machine breakdowns and considers two objectives makespan and robustness simultaneously.
Design/methodology/approach
Owing to its structural and algorithmic complexity, the authors proposed imperialist competitive algorithm (ICA), genetic algorithm (GA) and hybridized with simulation techniques for handling these complexities. For better efficiency of the proposed algorithms, the authors used artificial neural network (ANN) to predict the parameters of the proposed algorithms in uncertain condition. Also Taguchi method is applied for analyzing the effect of the parameters of the problem on each other and quality of solutions.
Findings
Finally, experimental study and analysis of variance (ANOVA) is done to investigate the effect of different proposed measures on the performance of the obtained results. ANOVA's results indicate the job and weight of makespan factors have a significant impact on the robustness of the proposed meta-heuristics algorithms. Also, it is obvious that the most effective parameter on the robustness for GA and ICA is job.
Originality/value
Robustness is calculated by the expected value of the relative difference between the deterministic and actual makespan.
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Keywords
Rasoul Shafaei, Hamid Shahriari and Morteza Moradi
The purpose of this paper is to investigate the competitiveness of the Iranian leather value chain (LVC) and compare that with those of nine other countries including China…
Abstract
Purpose
The purpose of this paper is to investigate the competitiveness of the Iranian leather value chain (LVC) and compare that with those of nine other countries including China, Pakistan, Turkey, Republic of Korea, Indonesia, Spain, Italy, Brazil and the USA. The results presented in the paper seek to assist in assessing the competitive performance of the LVC in Iran. In addition, based on Porter's diamond of competitive advantages, the aim is to provide recommendations to improve the competitive performance of the industry.
Design/methodology/approach
An economic method, i.e. revealed comparative advantage (RCA), as a well‐known approach, is used to investigate the competitive performance of LVC in Iran. The LVC products analyzed in this research include hide, skin, leather manufacture, trunks and cases, and footwear. In addition, in order to investigate the factors which affect the low competitive performance, a questionnaire based on Porter's diamond of competitive advantages was designed and completed by researchers and practitioners working in the field of leather industry. Finally the reasons for low competitive performance of the industry are discussed.
Findings
The results reveal that the competitiveness of the Iranian LVC is low, compared with those of some other countries. China and Italy have superior comparative advantages in the period studied. The results also indicate that except one product, Iran has no comparative advantage in LVC industry. In addition, Iran has mainly focused on the upstream sector of LVC whereas China and Italy compete more in the downstream sector which offers more value added products. The results also reveal that among the elements studied, specialized factors, availability of capital, quality of demand and stability of macroeconomics highly influence the competitive performance of LVC in Iran. This is followed by subsequent recommendations on how best to improve the competitive performance of the industry.
Originality/value
The results of the investigation presented in this paper give an insight into the competitiveness of the LVC in Iran compared with nine other countries which play an important role in this industry in the world. The results also confirm that RCA can be used as an effective approach to assess the competitive performance of industries. Furthermore, reommendations provided in this paper assist in improving the competitive performance of the industry. In general, the findings should prove useful for both researchers and practitioners.
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The purpose of this paper is to measure the competitive performance of four major Iranian synthetic fiber‐manufacturing companies, as one of the main sectors in the textile…
Abstract
Purpose
The purpose of this paper is to measure the competitive performance of four major Iranian synthetic fiber‐manufacturing companies, as one of the main sectors in the textile industry, using an analytical approach. The results presented assist in evaluating the competitive performance of a company, while developing recommendations for improving competitive strategy of the firms.
Design/methodology/approach
The proposed approach is based on Porter's diamond of competitive advantage (including four main determinants, namely factor conditions, demand, related and supporting industries and firm strategy and rivalry, plus government as an external factor). This approach is based on five determinants, each one consisting of two to six elements, with each element including a number of variables, i.e. 55 variables in total, which were confirmed by the interviewees as important factors affecting the competitiveness of a firm. Accordingly, the results obtained from the interviews confirmed the validity of the proposed approach to assess the competitiveness of a company. In addition the proposed approach is applied to assessing the competitive performance of four companies which manufacture synthetic fibers, in terms of each determinant as well as the overall competitive performance of each company. The data used in this research were obtained from both face‐to‐face interviews and a questionnaire completed by the key managers and engineers at the companies studied. The validity of the results obtained by means of the proposed approach was also correlated by comparing the results with the Export Value and Relative Comparative Advantage index of the synthetic fiber industry in Iran.
Findings
The results reveal that the competitiveness of the four companies is significantly low. Furthermore, of the five determinants, factor condition yielded the highest performance for the firms. The paper also identifies some of the shortcomings affecting the local manufacturers, and provides recommendations on how to improve the competitive performance of the firms.
Practical implications
The proposed approach provides a good basis for assessing the competitive performance of the companies. This can also help both researchers and practitioners in deciding how best to improve the competitive performance of a company.
Originality/value
The research proposes an analytical method for measuring the competitiveness of companies. This also helps in developing recommendations for improving competitive strategy. In addition, the method evaluates the competitive performance of four companies which play an important role in the Iranian synthetic fiber industry. Recommendations are also made on how to improve the performance. The findings should prove useful for both researchers and practitioners.
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Rasoul Amirzadeh and Mohammad Reza Shoorvarzy
The aim of the present research is firstly to examine and recognize the quality elements of services in the banks by SERVQUAL instrument and some Islamic banking factors…
Abstract
Purpose
The aim of the present research is firstly to examine and recognize the quality elements of services in the banks by SERVQUAL instrument and some Islamic banking factors. Secondly, the aim is to prioritize these factors based on fuzzy TOPSIS. Fuzzy logic provides a useful tool for dealing with decisions in which the phenomena are vague.
Design/methodology/approach
The present research was performed among bank customers. The required information was gathered through a designed questionnaire. Using fuzzy set theory, customers' perceptions of service quality are generally expressed subjectively in vague linguistic terms, and this paper tries to apply a fuzzy approach to service quality.
Findings
The result of this study shows that “short and suitable queue” and “confident and reliable staff” are the most important quality factors in bank service and on the other hand, “being equal with Islamic doctrines” and “accessible branches” are the least significant factors of service quality in the view of Iranian bank customers.
Practical implications
The results of the present research will be useful for bank decision makers to pay particular attention to indicators of most or least importance.
Originality/value
The concept of ranking quality factors in banking service using fuzzy TOPSIS is a new approach, especially in the field of Islamic banking. Banks have huge budgets, which can then be allocated for indicators of higher importance when the importance of each factor is determined.