45 research outputs found
An integrated fuzzy multi criteria group decision making model for handling equipment selection
The problem of handling equipment selection plays a significant role in the total cost of a mining project; so that it can affect the activity and continuity of the project and is a strategic problem. In this study, an integrated model based on two fuzzy multi-criteria decision making techniques for handling equipment selection is proposed. The proposed evaluation model is derived from group decision making, fuzzy set theory, analytical hierarchy process (AHP), and Technique to Order Preference by Similarity to Ideal Solution (TOPSIS) methods. The fuzzy AHP (FAHP) method is utilized to calculate the relative importance of the evaluation criteria, then, fuzzy TOPSIS (FTOPSIS) is applied for evaluating the feasible handling equipment in order to select the best handling system among a pool of the possible alternatives. The model is applied for a real world case study to demonstrate the capability and effectiveness of the proposed model. To investigate the result sensitiveness to the changes of the criteria weights, a sensitivity analysis is finally conducted
Proposing a new methodology based on fuzzy logic for tunnelling risk assessment
Tunnels are artificial underground spaces that provide a capacity for particular goals such as storage, under-ground transportation, mine development, power and water treatment plants, civil defence. This shows that the tunnel construction is a key activity in developing infrastructure projects. In many situations, tunnelling projects find themselves involved in the situations where unexpected conditions threaten the continuity of the project. Such situations can arise from the prior knowledge limited by the underground unknown conditions. Therefore, a risk analysis that can take into account the uncertainties associated with the underground projects is needed to assess the existing risks and prioritize them for further protective measures and decisions in order to reduce, mitigate and/or even eliminate the risks involved in the project. For this reason, this paper proposes a risk assessment model based on the concepts of fuzzy set theory to evaluate risk events during the tunnel construction operations. To show the effectiveness of the proposed model, the results of the model are compared with those of the conventional risk assessment. The results demonstrate that the fuzzy inference system has a great potential to accurately model such problems
KORIŠTENJE INTEGRIRANOG MCDM MODELA ZA ODABIR TEHNIKE RUDARENJA U SLUČAJU NESIGURNOSTI
The aim objective of this study is to model mining method selection problem for a real world case in Angouran mine which is one of the major zinc producers in Iran. According to many problems of ore body extraction are direct or indirect depend on underground mining method, this issue is one of the most critical decisions in the design stage of mine that should be made. A number of the evaluation criteria that often are in conflicting with each other exist for evaluating feasible mining methods. Therefore, the problem of mining method selection is a multi-criteria decision making (MCDM) issue.On the other hand, according to the sophisticated structure of the problem, imprecise data, less of information, and inherent uncertainty, the usage of the fuzzy sets can be useful. In this paper an integrated model based on fuzzy analytic hierarchy process (FAHP) and fuzzy technique for order preference by similarity to ideal solution (FTOPSIS) is developed. FAHP is applied to determine the relative weights of the evaluation criteria for mining method selection that these weights are inserted to the FTOPSIS technique to rank the alternatives and select the most appropriate alternative. The study was followed by the sensitivity analysis of the results. The results of this study demonstrate the efficiency, capability, and robustness of the proposed model, which can be applied to different types of sophisticated problems in reality.Cilj ovog rada je izvođenje efikasnog i primjenjivog modela odabira najbolje proizvodne tehnike na primjeru Angouran rudnika koji je jedan od glavnih proizvođača cinka u Iranu. Proizvodne tehnike ekstrakcije ruda su izravno ili neizravno ovisne o izboru tehnika izvlačenja ruda, jednog od najkritičnijih pitanja u odlučivanju u fazi projektiranja rudnika koji bi trebao biti izrađen. Broj evaluacijskih kriterija često su u sukobu jedni s drugima pri odabiru i ocjeni prihvatljive proizvodne (rudarske) metode i tehnike. Dakle, problem odabira prihvatljive proizvodne rudarske metode u praksi je problem odabira multi-kriterijskog odlučivanja (MCDM). S druge strane, s obzirom na složenost i strukturu problema, nepreciznih podataka, manjkavost informacija, a time i inherentnu nesigurnost, korištenje fuzzy tehnika može biti od iznimne koristi. U ovom radu integrirani model koji se temelji fuzzy analitičkoj hijerarhiji procesa (FAHP) i fuzzy tehnikama za redom preferencija po sličnosti idealnog rješenja (FTOPSIS) je razvijen i prezentiran. FAHP se primjenjuje za određivanje relativne težine kriterija za ocjenu najbolje proizvodne tehnike pri ekstrakciji ruda u odnosu na ostale dostupne alternativne proizvodne tehnike. Rezultati istraživanja rada testirani su analizom osjetljivosti rezultata. Rezultati ovog istraživanja pokazuju učinkovitost, sposobnost i robusnost predloženog modela izbora proizvodnih tehnika, koji se mogu primijeniti na različite vrste složenih problema u stvarnom životu
An integrated model for extending brand based on fuzzy ARAS and ANP methods
Brand extension is one of the most popular strategies in marketing. This is due to the fact that consumers usually take into account the brand first because it indirectly reflects the design, quality, and functions. According to the significant role of brand in creating benefit and diminishing risk for a new product, this study intended to develop a novel model for selecting the most appropriate strategy in brand extension. However, there are a number of criteria influencing the possible strategies, and they often are interdependent. Therefore, a multi-criteria decision making model based on Analytic Network Process and Additive Ratio Assessment methods has been developed to systematically clarify the interdependent relationships among the evaluation criteria of brand extension and then, scientifically evaluate the feasible strategies and rank the priorities of brand extension strategies. The results of the proposed model show that “Production cost” is the most important factor, followed by “Quality of parent brand” and “Perceived risk” while “Ice cream” is the highest satisfaction of brand extension
Waste Dump Site Selection by Using Fuzzy VIKOR
Considering the nature of open pit mines, harvest volume, it usually is required to remove a lot of waste to access to mineral planned grade. So, one of the most important part of open pit mines design, is waste dump site selection. Many factors are effective in waste dump site selection. These factors are sometimes in conflict with each other. So selecting the desired location for waste dump is a process complex and multi-criteria decision making. There are a variety of methods for decision making under complicated condition, such as fuzzy, Delphi, multi-criteria decision making and Expert system methods can be hinted. VIKOR method, which is one of the decision making multi criteria methods, is useful tool for decision-making. On the other hand with regard to uncertainty in decision-making, fuzzy approach is a useful tool for this purpose. This article has tried to select the best waste dump site in Sari Gunay Gold Mine by Fuzzy VIKOR. The results show that C position has a higher priority than other positions
Proposing a new methodology for prioritising the investment strategies in the private sector of Iran
This article proposes a systematic and organised approach for group decision-making in the presence of the uncertainty involved in expert judgments as used in multi-criteria decision-making (MCDM) issues. This procedure comprises the selection of the optimum alternative with respect to the evaluation criteria under consideration, in particular to select the strategy of investing. However, the selection of
the investment strategy is difficult on account of considering the numerous quantitative and qualitative parameters like benefits, opportunities, costs, and risks. However, it is possible that these parameters have a significant influence on each other. A decision-making trial and evaluation laboratory (DEMATEL), used to define the
influential network of elements, can be employed to construct a network relationship map (NRM). On the other hand, according to whether the information is incomplete or unavailable, uncertainty is an inseparable part of making decision for solving the MCDM problems. Therefore, this article proposes a new hybrid model
based on analytic hierarchical process (AHP), DEMATEL, and echnique for Order of Preference by Similarity to Ideal Solution (TOPSIS) techniques under fuzzy environment to evaluate the problem of the selection of the investment strategy. To achieve the aim, a three-step process is presented to solve a sophisticated problem. First, the AHP method is employed to break down the investment problem into simple structure and calculate the importance weights of criteria by using a pairwise comparison process. Second, the DEMATEL technique is applied for considering interdependence and dependencies and computing the global weights of benefit, opportunities, cost, and risk (BOCR) factors. Finally, the fuzzy TOPSIS methodology is used for prioritising the possible alternatives. To demonstrate the potential
application of the proposed model, a numerical example is illustrated and investigated. The results show that the proposed model has a high ability to prioritise the strategies of investing
Environmental impact assessment based on group decision-making methods in mining projects
Mining operations usually comprise a spread spectrum of environmental challenges, which are often unique to each mine site. This is due to the fact that mining activities, directly or indirectly, have an adverse impact on environment and ecology. For this reason, the environmental impact assessment (EIA) process has been developed
for evaluation of the possible impact of mine development and operations on the environment, including the natural, social and economic aspects. In this article, an EIA methodology based on analytic network process and fuzzy simple additive weight (SAW) is proposed to formulate the environmental risks pertaining to mining
projects. In the system of the proposed model, the importance weights are calculated by an ANP process. Then, fuzzy SAW is employed to evaluate the preference ratings of the alternatives. The merit of using fuzzy logic is to handle the inherent uncertainty in modelling an EIA problem by simplifying the sophisticated structure of the problem under consideration. The proposed model is utilised to assess the environmental impact generated by zinc and lead mining projects located in Zanjan, Iran to shape the future industrial and mining structure of the region. Finally, the environmental impacts are ranked from the most to the least risky
Developing a new approach for evaluation of business processes in a fuzzy environment
Evaluation of business processes plays a significant role in business development and improvement. Therefore, organizations need a systematic approach to evaluate all the changes through robust and powerful techniques that can formulate the relationship between the available information and the degree of the inherent uncertainty. In this paper, a set of operational variables are defined. Then, the SPSS software package is utilized to validate the gathered data. After that, the variables are categorized by the use of a clustering technique. Finally, five major factors are determined as the most effective components. According to the inherent uncertainty involved in the process of modelling, fuzzy set theory, a powerful mathematical tool is applied to handle the vagueness. In order to construct a knowledge base based on the fuzzy set theory, the linguistic concepts for each variable are defined. Lastly, membership functions are described and a set of fuzzy rules based on input-output parameters are written in MATLAB software environment. To demonstrate the potential application of the proposed approach, a real case study is illustrated. The results reflect the capability and effectiveness of the approach proposed in this paper.
First published online: 23 Nov 201
Project risk evaluation by using a new fuzzy model based on Elena guideline
The complexity and dynamics of the executive projects have coped contractors with substantial hazards and losses. Project risk management is a critical tool for authority to improve its performance and secure the success of the organization. However, a number of standards and approaches have been developed to formulate the projects based on their risks. The Elena guideline is a systematic standard developed by Iran Project Management Association. This guideline provides the full cycle of the risk management process. Risk evaluation is the key part of the risk management process. On the other hand, different techniques have been developed to model a risk evaluation problem. Fuzzy inference system is one of the most popular techniques that is capable of handling all types of the uncertainty involved in projects. This paper proposes a three-stage approach based on the fuzzy inference system under the environment of the Elena guideline to cope with the risky projects. Finally, an illustrative example of the risk evaluation is presented to demonstrate the potential application of the proposed model. The results show that the proposed model evaluates the risky projects efficiently and effectively