A three-stage assembly flow shop scheduling problem with blocking and sequence-dependent set up times

This paper considers a three-stage assembly flowshop scheduling problem with sequence-dependent setup times at the first stage and blocking times between each stage in such a way that the weighted mean completion time and makespan are minimized. Obtaining an optimal solution for this type of complex, large-sized problem in reasonable computational time using traditional approaches or optimization tools is extremely difficult. Thus, this paper proposes a meta-heuristic method based on simulated annealing (SA) in order to solve the given problem. Finally, the computational results are shown and compared in order to show the efficiency of our proposed SA

Ranking effective factors on production of electronic brand among private banks of Iran

The purpose of the present study is to use analytic hierarchy process for ranking the effective factors on production of electronic brand, to use the DEMATEL method to find the intensity of influence of effective factors on production of electronic brand, and to use the TOPSIS method for ranking the five banks including Saman Bank, Sarmayeh Bank, Parsian Bank, Pasargad Bank, EN Bank in Iran. From the analytic hierarchy process results, we understood that “the security and easy to use” is the most important effective factors on production of electronic brand. The results of DEMATEL method showed that “quality of relationship with customer and reputation” is the most influence and the strongest connection to other criteria. Finally, the results of DEMATEL method indicated that EN Bank and Saman Bank were regarded as the best banks

A Comparison of the REMBRANDT System with a New Approach in AHP

Analytic hierarchy process (AHP) has been criticized considerably for possible rank reversal phenomenon caused by the addition or deletion of an alternative. While in many cases this is a perfectly valid phenomenon, there are also many cases where ranks should be preserved. Our findings indicate that using the geometric mean reduces the variance in ratings substantially; hence, yielding lower inconsistency in ratings. An approach is therefore proposed using the geometric mean aggregation to avoid rank reversal phenomenon. A practical example is examined using the proposed approach to demonstrate its validity and racticability in rank preservation. This paper also compares the REMBRANDT system with the proposed approach to avoid rank reversal phenomenon

Influence of fuzzy Goal Programming in Production Optimization Case study: Cement Industry

Using the mathematic techniques such as Fuzzy approach has useful outcomes for production planning in different sources. In this paper LGP1 was used to model the objectives such as: avoidance of shortage or surplus of demand, access to maximum of income, using the normal capacity of production and organizing the inventory of warehouse, within the framework of Goal constraints like balancing between demand and inventory, rate of production within every period and the constraints of threshold of inventory at the end of every month. On these lines, the goal programming is one of the best methods for analyzing the multi objective decision making in cement industry management. The most principal disadvantage of goal programming is that all the parameters of model should be defined carefully and all of the objectives and constraints should certainly be determined. For taking over on this problem we introduced the Fuzzy concept. In this research, the mathematic goal programming model in the cement industry is modeled by Fuzzy and absolute approach. This research is intended to answer this question, which one presents the optimal solution for production process planning, Fuzzy or absolute approach? The necessity information to do this research is obtained with using field methods, desk surveys, observations, factory documents, and interviews or questionnaires. In this article we use GP to formulize, AHP2 for grading and weighting and LINGO for solving. Afterwards, the data are entered in the formula modeled before and are solved using LINGO software

Designing a Model for Strategic Digital Thinking Competence Evaluation in National Gas Company of Iran

Purpose: With the increase of problems and the complexity of organizations, the need to provide better solutions and use more powerful tools of strategic planning is evident because managers with strategic thinking and a better understanding of the strategic plan will perform more effectively. It can be said that strategic thinking is considered as a supplement to strategic planning, a suitable approach to "leadership" of the organization and can help in systematically dealing with problems, understanding opportunities, optimal allocation of scarce resources and achieving the desired results. In view of this importance, the current research aims to design a strategic thinking competence assessment model with the approach of developing organizational flexibility in National Gas Company of Iran. Method: This research is applied in terms of purpose and was done with qualitative approach based on grounded theory method. Sampling of the research was done using snowball method (chain reference). For this purpose, qualitative data was collected, which led to the identification of many aspects of the phenomenon and the possibility of developing a conceptual research model. The data collection method is library studies, perusal of high-level documents, and in-depth and open interviews. The statistical population of this research consisted of specialists and experts in the field of management and strategic thinking, of whom 12 people were investigated. In the process of conducting this research, the interviews continued until theoretical saturation was observed. Findings: The findings showed that six main categories are effective on the evaluation of strategic thinking with an organizational flexibility approach, which are: foresight, strategic determination, systemic attitude, innovation and creativity. The results show that the validity of the model is confirmed and the six obvious variables (six dimensions) explain the latent variables of strategic thinking competency assessment. According to the direction of all the relations between the manifest variables and the latent ones, , all the relations are aligned and direct. Conclusion: According to the amount of standardized factor loadings, the dimension "Foresight (AN)", with a factor loading of 0.88, is the most reliable indicator belonging to evaluation measurement

Proposing a Novel Method for Optimal Location Finding Based on Machine Learning Algorithms and Gray Wolf Optimization

With the expansion of human activities, the volume of waste and hazardous waste produced has increased dramatically. Increasing the volume of waste has created challenges such as transportation hazards, cleanup, disposal, energy consumption, and most important environmental problems. The difficulty of unsafe waste control is one of the critical studies topics. Finding the optimal location of hazardous waste disposal is one of the issues that, if done properly, can significantly reduce the aforementioned challenges. The increasing volume of information, the complexity of multivariate decision criteria, have led to the lack of conventional methods for finding the optimal location. Machine learning methods have proven to be effective and superior in many areas. In this paper, a new method based on machine learning for finding the optimal location of hazardous waste disposal is presented. In the proposed method, after applying clustering in the separation of the desired areas, the gray wolf algorithm optimization is used to find the optimal location of waste disposal. In order to apply the gray wolf optimization algorithm, a multivariate target function is defined. Cluster centers as were chosen as location of waste disposal. Proposed method is performed on collected data from the study area in Iran, Tehran province.  Proposed clustering method is evaluated and compared with some metaheuristics algorithm. The simulation results of the proposed method show cost reduction in finding the desired locations compared to similar researches. Also, Xi and Separation index was used for evaluation of the proposed clustering method to select the best location. The number of best locations using Xi and Separation index claim the superiority of the proposed method