Journal of Quality Engineering and Production Optimization
Volume:3 Issue: 1, Winter - Spring 2018

Satisfying customer demand necessitates manufacturers understanding the importance of Available-To-Promise (ATP). It directly links available resources to customer orders and has significant impact on overall performance of a supply chain. In this paper, an improvement of the batch-mode ATP function in which the partial fulfillment of the orders is available will be proposed. In other words, in a hybrid make-to-order/make-to-stock manufacturing environment, the proposed model responds to customer’s requests in 3 different ways; rejecting, fulfilling, and partial fulfilling. By using this procedure, the reliability of order fulfillment and the responsiveness of order promising will be enhanced. To evaluate the applicability of the proposed model, some numerical examples and sensitivity analysis are conducted. Results show that by applying partial fulfilment and penalty to backorders, the number of rejected orders and profit would be minimized and maximized, respectively.

Job shop scheduling problem (JSP) is an attractive field for researchers and production managers since it is a famous problem in many industries and a complex problem for researchers. Due to NP-hardness property of this problem, many meta-heuristics are developed to solve it. Solution representation (solution seed) is an important element for any meta-heuristic algorithm. Therefore, many researchers try to present different encodings to solve this problem. Fattahi et al., and Gen & Cheng suggested two solutions for this problem that both have advantages and weaknesses in searching solution space to reach an acceptable solution. In the current paper, a cyclic algorithm based on tabu search algorithm was proposed to improve the exploration and exploitation powers of these encodings. Also, several problems of different sizes are solved by it and the obtained results were compared. Results showed the applicability and effectiveness of the proposed solution representation in comparison with the existing ones

A fresh look at the system analysis helped us in finding a new way of calculating the risks associated with the system. The author found that, due to the shortcomings of RPN, more researches needed to be done in this area to use RPNs as a new source of information for system risk analysis. It is the purpose of this article to investigate the fundamental concepts of failure modes and effects analysis to propose a conceptual hierarchically based model for calculating the risk associated with a system in general. To do so, the author developed a chance constrained goal programming model for solving the problem.
A sample problem is provided to show the calculation process of risk evaluation. The findings of this article can be used for calculating the level of risk associated with the entire system provided that the RPN of each unit of subsystems is known beforehand. This model helps the managers to calculate the system risk from the perspective of management, because it is a computer aided decision making (CADM) tool

Using Multi-Criteria Decision-Making (MCDM) to solve complicated decisions often includes uncertainty, which could be tackled by utilizing the fuzzy sets theory. Type-2 fuzzy sets consider more uncertainty than type-1 fuzzy sets. These fuzzy sets provide more degrees of freedom to illustrate the uncertainty and fuzziness in real-world production projects. In this paper, a new multi-criteria analysis model is introduced based on new compromise ratio and relative preference relation methods by vicinity to positive ideal and distance from negative ideal concepts under an interval type-2 fuzzy environment. Also, qualitative criteria are expressed as linguistic variables. Relative preference relation is more reasonable than defuzzification, because defuzzification cannot provide preference degree between two fuzzy numbers and cannot keep all the information. In this paper, an extended relative preference relation over the average is presented to deal with numeral values. Finally, a real application to designing and manufacturing of small electronic components, particularly for the aviation, defense, and space industries, is adopted from the literature and solved to determine the critical path by considering efficient criteria such as time, cost, risk, and quality.

This study aims to apply Grey system based on modified E-S-Qual model to analyze e-service quality.Questionnaires on the basis of E-S-Qual model, which consisted in 7 dimensions, were distributed among customers of 5040.ir, an online retailer in Iran. 251 questionnaires were obtainedfrom the customer’s website. After applying the method and calculating the scores in each dimension, the gap between expectations and perceptions was calculated. The results show that, among 7 dimensions, there are 4 positive and 3 negative gaps.Accordingly,with the aid of the Importance-Performance Matrix, the results are further analyzed. At the end of this study, some suggestions are made for improving quality of the e-services based on results analysis

Missing observations occur in experimental designs as a result of insufficient sampling, machine breakdown, high cost, and errors in the measurements. In nanomanufacturing, missing observations often appear in designs because the combination of factors or molecular structures selected by a designer cannot be experimented successfully. In the current paper, Box-Behnken and face-centered composite designs were studied and eight robustness criteria including D-efficiency, tmax, tmaxþ(), and their related sub-criteria were considered to evaluate the robustness of the aforementioned designs. Finally, the integrated TOPSIS-AHP methodology was employed to select the most suitable robust design, and a numerical example was also presented to assess the applicability of the proposed approach