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202 items
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Development of Integrated Fuzzy Model for Mine Management Optimization
Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić (2023)Technoeconomic, environmental and safety criteria generally affect the management of metallic and non-metallic mining operations. The first basic question that needs to be addressed when planning ore mining is which methods are adequate and what is the optimal mining technology? Due to the complex geologic framework of ore deposits, geological exploration has rendered synonymous the inherent uncertainties, vagueness, and inaccuracies. As a result, subjective evaluation by engineers and expert experience have become increasingly important. Given that the natural language ...Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić. "Development of Integrated Fuzzy Model for Mine Management Optimization" in Comptes rendus de l’Académie Bulgare des Sciences, Bulgarian Academy of Sciences (2023). https://doi.org/10.7546/CRABS.2023.09.12
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Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station “Bezdan 1”, Serbia
Dragoljub Bajić, Dušan Polomčić (2014)A groundwater control system was designed to lower the water table and allow the pumping sta-tion “Bezdan 1” to be built. Based on a hydrodynamic analysis that suggested three alternative solutions, mul-ticriteria optimization was applied to select the best alternative. The fuzzy analytic hierarchy process methodwas used, based on triangular fuzzy numbers. An assessment of the various factors that influenced the selec-tion of the best alternative, as well as fuzzy optimization calculations, yielded the “weights” of the alternativesand the ...groundwater lowering, groundwater management scenario, fuzzy analytic hierarchy process,expert knowledge, triangular fuzzy numbers, linguistic variables... j = 1, 2, …, m are triangular fuzzy numbers. Then, taking into account the membership function of the triangular fuzzy numbers, the value of the fuzzy synthetic extent is computed using the expression: Step 3. In this step the degree of possibility of two triangular fuzzy numbers (Fig. 3) M1 = (l1 ...
... the membership functions To compare the triangular fuzzy numbers M1 and M2, both values, V(M1 ≥ M2) and V(M2 ≥ M1) are needed. Fig. 3. Triangular fuzzy number. The degree of possibility of a convex fuzzy number to be greater than k, the convex fuzzy numbers Mi can be defined by i=1,2,…,k: DRAGOLJUB ...
... 2, the calculated values of the fuzzy synthetic extent were as follows: According to Step 3, the fuzzy numbers were com- pared and the degree of possibility of two triangular fuzzy numbers (i.e. their values of fuzzy synthetic extent) was determined as follows: Fuzzy optimization in hydrodynamic analysis ...Dragoljub Bajić, Dušan Polomčić. "Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station “Bezdan 1”, Serbia" in Geološki anali Balkanskoga poluostrva, Belgrade : University of Belgrade - Faculty of mining and geology (2014). https://doi.org/10.2298/GABP1475103B
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Development of integrated fuzzy model for mine management optimization
Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić (2023)... element of set X: ]W;„]Wž, ... ,]W;il, + = 1,2,...,n, where all MŠ„» J = 1,2,...,m are triangular fuzzy numbers. Then, taking into account the membership function of the triangular fuzzy number, the fuzzy synthetic extent is calculated using; the following; equation: m i n m -1 m m m 1 1 1 ...
... possibility of two triangular fuzzy numbers is deter- mined using; the fuzzy number comparison approach: V(M, > W)= sup |min (Jr, () , R,Ma (9))] . z>u If there are such pairs (z,y) that r > y and a (T) = HM,(U) = l, then V (Mi > M») = 1. Given that Mi and M»are convex triangular fuzzy number, it ...
... weight coefHicients. The scores and weights are represented by triangular fuzzy numbers. Table 2 shows the scores of the alternatives relative to each criterion, as well as the weight coefHcients. Additionally, triangular fuzzy numbers are used to show the comparison of all alternatives relative ...Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić. "Development of integrated fuzzy model for mine management optimization" in Comptes rendus de l'Académie Bulgare des Sciences (2023)
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Hybrid model of evaluation of underground lead–zinc mine capacity expansion project using Monte Carlo simulation and fuzzy numbers
Gligorić Zoran, Beljić Čedomir, Gluščević Branko, Jovanović Saša. "Hybrid model of evaluation of underground lead–zinc mine capacity expansion project using Monte Carlo simulation and fuzzy numbers" in Simulation: Transactions of the Society for Modeling and Simulation International 8 no. 87, :Sage Science Press (UK) ^Subsidiary of: Sage Publications, Inc. (2011): 726-742. https://doi.org/10.1177/0037549711410902
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Development of an integrated model for open-pit-mine discontinuous haulage system optimization
Miodrag Čelebić, Dragoljub Bajić, Sanja Bajić, Mirjana Banković, Duško Torbica, Aleksej Milošević , Dejan Stevanović (2024)Miodrag Čelebić, Dragoljub Bajić, Sanja Bajić, Mirjana Banković, Duško Torbica, Aleksej Milošević , Dejan Stevanović . "Development of an integrated model for open-pit-mine discontinuous haulage system optimization" in Sustainability, MDPI (2024). https://doi.org/10.3390/su16083156
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A Model for Determining the Dependability of Continuous Subsystems in Coal Mines Using the Fuzzy Logic Approach
Nikola Stanić, Miljan Gomilanović, Petar Marković, Daniel Krzanović, Aleksandar Doderović, Saša Stepanović (2024)This study presents a unique model for assessing the dependability of continuous parts of combined systems in open-pit mining through the application of fuzzy logic. Continuous sub-systems as part of the combined system of coal exploitation in surface mines have the basic function of ensuring safe operation, high capacity with high reliability, and low costs. These subsystems are usually part of the thermal power plant’s coal supply system and ensure stable fuel supply. The model integrates various independent partial ...fuzzy logic, max-min composition, continuous part of combined system (CCS), open pit, mining, dependabilityNikola Stanić, Miljan Gomilanović, Petar Marković, Daniel Krzanović, Aleksandar Doderović, Saša Stepanović. "A Model for Determining the Dependability of Continuous Subsystems in Coal Mines Using the Fuzzy Logic Approach" in Applied Sciences, Basel, August 2024, MDPI (2024). https://doi.org/https://doi.org/10.3390/app14177947
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A multi-criteria approach for assessing the potential of renewable energy sources for electricity generation: Case Serbia
When assessing the potential of renewable energy alternatives for electricity generation, it is necessary to implement a multi-perspective approach that includes economic, technical, environmental, and socio-political criteria. For the evaluation of criteria and alternatives, the Fuzzy Analytical Hierarchy Process (FAHP) method is applied. The obtained weights are formed according to the values of energy indicators and expert judgments. The use of a fuzzy numerical value scale for the assessment of expert judgments and energy indicators provides a more sensitive ...... RESs, are presented in Table 3. As can be seen from Table 3, numerical scales are represented by triangular fuzzy numbers (TFNs). The TFN is defined as fuzzy number M (l, m, u) on R (set of real numbers) if its membership function µM(x): R→ [0,1] is equal to (Chang, 1996): µM(x) = ⎧ ⎨ ⎩ x m−l − ...
... well as a pairwise comparison of RESs with respect to socio-political criterion. Each of these linguistic variables is assigned one of the triangular fuzzy numbers (TFNs) (Table 3) (Dubois et al., 2007). In the case of experts ‘assessment of the criteria and experts’ prioritization of RES alternatives ...
... higher share for 45.52%, i.e., biomass has ‘‘absolute importance’’ over wind energy. Each of the linguistic variables is assigned one of the triangular fuzzy numbers (TFNs). The linguistic variables and corresponding intervals of the differences of indicator values’ share, as well as the appropriate TFNs ...Boban Pavlović, Dejan Ivezić, Marija Živković. "A multi-criteria approach for assessing the potential of renewable energy sources for electricity generation: Case Serbia" in Energy Reports, Elsevier BV (2021). https://doi.org/10.1016/j.egyr.2021.02.072
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Determining the Availability of Continuous Systems at Open Pits Applying Fuzzy Logic
This work presents a model for determining the availability of continuous systems at open pits by applying fuzzy logic and fuzzy inference systems. The applied model was formed by the synthesis of independent partial indicators of availability. The model is based on an expert system for assessing the availability of continuous mining systems. The availability of the system, as a complex state parameter, is decomposed into the partial indicators, reliability, and convenience of maintenance, and the fuzzy compositions, used ...системи, континуални систем експоатације, површински коп, рударство, расположивост, фази логика, max–min композиција, min–max композицијаMiljan Gomilanović, Miloš Tanasijević, Saša Stepanović. "Determining the Availability of Continuous Systems at Open Pits Applying Fuzzy Logic" in Energies, MDPI AG (2022). https://doi.org/10.3390/en15186786
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Prioritization of strategic measures for strengthening the security of supply of the Serbian natural gas sector
To strengthen the security of supply of the Serbian gas sector, it is necessary to analyze the impact of planned strategic measures. The analysis involves the identification of the most influential threats to the security of natural gas supply and prioritization of the strategic measures for overcoming the consequences of threats. The proposed methodology is based on Fuzzy Analytic Hierarchy Process. The obtained weights for the identified threats and strategic measures are formed according to experts' judgments. The results ...Sigurnost snabdevanja, Donošenje odluka, Snabdevanje prirodnim gasom, Fazi AHP, Energetski indikatoriBoban Pavlović, Dejan Ivezić, Marija Živković. "Prioritization of strategic measures for strengthening the security of supply of the Serbian natural gas sector" in Energy Policy, Elsevier BV (2020). https://doi.org/10.1016/j.enpol.2020.111936
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A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers
Effectiveness evaluation is one of the basic components of engineering asset management and maintenance engineering in general. Effectiveness is an overall concept representing a measurement of quality of service level for the analyzed engineering system. This concept contains a series of partial indicators relating to time in operation and time for maintenance activities, as well as functional properties of the system. This article describes the analysis and structuring of partial indicators, as well as the development of a model ...Miloš Tanasijević, Predrag Jovančić, Dejan Ivezić, Uglješa Bugarić, Radiša Đurić. "A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers" in International Journal of Industrial Engineering: Theory, Applications and Practice (2019)
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Application of the Fuzzy Model in the Evaluation and Selection of Hydraulic Excavators on Open-Pit Lignite Mine
Stevan Đenadić, Miloš Tanasijević, Vladimir Milisavljević, Dragan Ignjatović, Predrag Jovančić (2021)The production of lignite in large open-pit mines is mainly performed with continuously operating equipment, where bucket-wheel excavators, bucket-chain excavators, belt conveyors, and spreaders are the basic machines. Smaller machines, usually of discontinuous operating nature, are commonly categorized as auxiliary machines. This paper presents the research related to the analysis of auxiliary machine parameters with the case study for a hydraulic excavator. The purpose of the analysis was to develop a model of rating quality of service of the ...Stevan Đenadić, Miloš Tanasijević, Vladimir Milisavljević, Dragan Ignjatović, Predrag Jovančić. "Application of the Fuzzy Model in the Evaluation and Selection of Hydraulic Excavators on Open-Pit Lignite Mine" in SSRN Electronic Journal, Elsevier BV (2021). https://doi.org/10.2139/ssrn.3945617
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An Underground Mine Ore Pass System Optimization via Fuzzy 0–1 Linear Programming with Novel Torricelli–Simpson Ranking Function
rudna sipka, optimizacija, fazi linearno programiranje, trouglasti graf, Toričelijeva tačka, funkcija rangiranjaDževdet Halilović, Miloš Gligorić, Zoran Gligorić, Dragan Pamučar. "An Underground Mine Ore Pass System Optimization via Fuzzy 0–1 Linear Programming with Novel Torricelli–Simpson Ranking Function" in Mathematics (2023). https://doi.org/10.3390/math11132914
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Fuzzy expert analysis of the severity of mining machinery failure
Mining machinery failure is almost an everyday occurrence. Usually the failures bare certain consequences, which require additional financial costs to repair and restore the system to its operational state. The consequences are viewed through negative and damaging effects a failure has on the machine, health and safety of the employees, work environment, and on the environment. The removal of the consequences of the failure requires additional financial investment, which has a negative impact on the company’s business. In order ...Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković. "Fuzzy expert analysis of the severity of mining machinery failure" in Applied Soft Computing, Elsevier BV (2020). https://doi.org/10.1016/j.asoc.2020.106459
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A Model for Determining Fuzzy Evaluations of Partial Indicators of Availability for High-Capacity Continuous Systems at Coal Open Pits Using a Neuro-Fuzzy Inference System
This paper presents a model for determining fuzzy evaluations of partial indicators of the availability of continuous systems at coal open pits using a neuro-fuzzy inference system. The system itself is a combination of fuzzy logic and artificial neural networks. The system availability is divided into partial indicators. By combining the fuzzy logic and artificial neural networks, a model is obtained that has the ability to learn and uses expert judgment for that learning. This paper deals with the ...системи, континуални системи експлоатације (роторни багер-транспортер-дробилично постројење), рударство, расположивост, меко рачунарство, фази логика, ANN, ANFISMiljan Gomilanović, Miloš Tanasijević, Saša Stepanović, Filip Miletić. "A Model for Determining Fuzzy Evaluations of Partial Indicators of Availability for High-Capacity Continuous Systems at Coal Open Pits Using a Neuro-Fuzzy Inference System" in Energies, MDPI AG (2023). https://doi.org/10.3390/en16072958
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Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine
Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović (2019)Availability is one of the most used terms in maintainability engineering. This concept is used to denote: The quality of service of an engineering system, i.e., machines, weak points’ analysis, asset management, as well as making decisions in the process of life cycle management. Availability is an overall indicator and contains partial indicators that are oriented towards reliability, maintenance, and logistical support. Availability presents a variable value and changes in time and space. Usually, availability is shown as the ...... partial assessments and is used, for example, to represent risk priority number. Below, a fuzzy min–max model of the composition is shown (steps i–vii). Ai = max { min(Ri, Mi, Si) } (8) (i) Three fuzzy numbers Ri, Mi иSi are defined through membership function µ and class j = 1 to n: Ri = (µR(1), ...
... expected partial assessments and is used, for example, to represent risk priority number. Below, a fuzzy min-max model of the composition is shown (steps i—vii). Aj = max{min(R;, M,, S;)} (8) (i) Three fuzzy numbers R;, M; 1S; are defined through membership function p and class j = 1 to n: R; = (UR(1), ++ ...
... allows the possibility of mapping the membership Energies 2019, 12, 4044 8 of 18 function to classes (14) in the membership function of the fuzzy numbers (15), respectively mapping the membership function into a given final value in the membership function to a given surface. The model is based ...Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović. "Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine" in Energies, MDPI AG (2019). https://doi.org/10.3390/en12214044
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A Fuzzy Expert Model for Availability Evaluation
Each technical system within itself carries the great potential danger of possible occurrence of failure and damages. Mining machines are characteristic by great investment values, costs of unplanned shutdowns, complex working conditions, and environment and workers hazards. Systematic monitoring of the mining machinery is of great importance for the management of the mining companies. Availability is the overall concept of quality of service. Includes information regard to operating state, an idle state, a standby state and shut down. The ...... assessment. This approach creates an environment for the fuzzy inference engine. Fuzzy sets are in triangular form and these are shown in figure 2, in relation to membership function (μ) and measurement units of A indicators (j = 1 … n). The fuzzy sets of R, M and S indicators have the same form. Values ...
... describe five linguistic variables i.e. fuzzy sets: poor, adequate, average, good and excellent. Fuzzy sets are in triangular form, and they are presented in relation to membership function (μ) and measurement units of A indicators (j = 1 … 5). Defined A fuzzy set can be written as: - poor = (1/j=1 ...
... Field D – F) were considered. Availability evaluation was made based on experts’ judgments and assessments. The fuzzy inference engine is used to synthesize mentioned fuzzy numbers (R, M and S) into one overall (A). Identification of obtained results, for their easier interpretation, is presented ...Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić. "A Fuzzy Expert Model for Availability Evaluation" in Proceedings of the 2019 20th International Carpathian Control Conference (ICCC), AGH University of Science and Technology, Kraków - Wieliczka, Poland (2019)
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Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements
The capacity of the rotor excavator depends largely on the operation of the subsystem for digging. There is a great contribution to the correct and sharp teeth when the capacity is the highest. In the function of time, the teeth become clogged due to abrasive wear, or changes in their geometric shape. To analyze the bucket wheel drive in depend on wear of the cutting elements in this study adaptive neuro fuzzy inference system (ANFIS) approach was implemented. ANFIS ...Filip Miletić, Predrag D. Jovančić, Milos Milovančević, Dragan Ignjatović. "Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements" in Advances in Engineering Software, Elsevier BV (2020). https://doi.org/10.1016/j.advengsoft.2020.102824
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Gate Road Support Deformation Forecasting Based on Multivariate Singular Spectrum Analysis and Fuzzy Time Series
Luka Crnogorac, Rade Tokalić, Zoran Gligorić, Aleksandar Milutinović, Suzana Lutovac, Aleksandar Ganić (2021)Underground mining engineers and planners in our country are faced with extremely difficult working conditions and a continuous shortage of money. Production disruptions are frequent and can sometimes last more than a week. During this time, gate road support is additionally exposed to rock stress and the result is its progressive deformation and the loss of functionality of gate roads. In such an environment, it is necessary to develop a low-cost methodology to maintain a gate road support system. ...deformacije podgrade, lasersko skeniranje, višekanalna singularna spektralna analiza, prognoza, klasterisanje fuzzy vremenskih serija... of obtained principal components. Clustering based on fuzzy time series enables us to see how the configuration of the gate road support has generally changed over time and defines the intervals of deformation by adequate triangular fuzzy numbers. Making decisions and plans based on the intervals is ...
... ∆VR = [−0.0007, 0.2027 ]. According to Equation (19) the length of interval is 0.0338. Quantification of the linguistic variables by the triangular fuzzy numbers is repre- sented in Table 17. Table 17. Variables obtained by quantification. Variable ai bi ci A1 −0.0007 0.0332 0.0671 A2 0.0332 0.0671 ...
... observation of displacement. Triangular fuzzy number O(t) =(a(t), b(t), c(t)) is also used to represent displacement of all markers at time point t, where a(t), b(t), c(t) are the left, middle and right values of the triangular fuzzy number, respectively. These values are defined in the following way: ...Luka Crnogorac, Rade Tokalić, Zoran Gligorić, Aleksandar Milutinović, Suzana Lutovac, Aleksandar Ganić. "Gate Road Support Deformation Forecasting Based on Multivariate Singular Spectrum Analysis and Fuzzy Time Series" in Energies, MDPI (2021). https://doi.org/https://doi.org/10.3390/en14123710
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The Fuzzy–AHP Synthesis Model for Energy Security Assessment of the Serbian Natural Gas Sector
Natural gas is used for the production of almost 20% of total energy today. The natural gas security of the Republic of Serbia is an urgent strategic, political and security issue. Serbia is one of the most vulnerable countries in Southeast Europe, because it only has one supply route. This study is a contribution to efforts to better understand the factors affecting energy security through the implementation of a new methodology based on the fuzzy–AHP synthesis model for measuring ...... relatively high score through the marginalization of estimation errors [63,64]. The fuzzy asymmetric max–min composition model (steps 1–8) will be shown below [65]. Мi =max{min(P1i, P2i, P3i)} (11) 1. Three fuzzy numbers P1i, P2i and P3i are defined by the membership function µ and class j = 1 to n: ...
... Serbia will follow the procedure algorithm described in Section 3 (Equations (11)–(17)). Based on the analysis of the partial indicators, three fuzzy numbers for the synthesis indicators A, S and E are defined in first level of the synthesis. Considering all possible combinations, the ones that satisfy ...
... ranking problem: A fuzzy set approach. Fuzzy Sets Syst. 1984, 13, 25–37. [CrossRef] 49. Bortolan, G.; Degani, R. A review of some methods for ranking fuzzy subsets. Fuzzy Sets Syst. 1985, 15, 1–19. [CrossRef] 50. Zadeh, L.A. Fuzzy Logic = Computing with words. IEEE Trans. Fuzzy Syst. 1996, 4, 103–111 ...Aleksandar R. Madžarević, Dejan D. Ivezić, Miloš L. Tanasijević, Marija A. Živković. "The Fuzzy–AHP Synthesis Model for Energy Security Assessment of the Serbian Natural Gas Sector" in Symmetry, MDPI AG (2020). https://doi.org/10.3390/sym12060908
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Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic
Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković (2020)Artificial lift methods have applications in oil wells where oil production is no longer possible due to natural reservoir energy, so this necessary energy is added by introducing lift methods. In order to achieve optimum production, the selection of an artificial lift method is very important. This paper uses fuzzy logic as a mathematical and conceptual model for selection of the optimal artificial lift method. The outcome or IF-THEN rules, as the central part of the model, is based ...... C) into one (M) is performed by fuzzy composition, which is a model that provides the structure of indicators-influencing M performance. In other words, if the influence indicators A, B and C are presented as fuzzy numbers [20], their composition provides a fuzzy number which represents M. Max-min ...
... defined linguistic variables (i.e., fuzzy sets) are: very low, low, moderate, high, and very high. The expert assessment consists of linguistic variables and the extent to which they apply to the observed well. Figure 2. Fuzzy sets. In dependence of μ, fuzzy number (FN) can be presented in form ...
... j = 1, 2; μ = 0 for j = 3, ..., 10. Other fuzzy sets can be written as: low = (0/1, 0/2, 1/3, 1/4, 0.33/5, 0/6, 0/7, 0/8, 0/9, 0/10) moderate = (0/1, 0/2, 0/3, 0.5/4, 1/5, 1/6, 0.5/7, 0/8, 0/9, 0/10) Figure 2. Fuzzy sets. In dependence of µ, fuzzy number (FN) can be presented in form (1): FN ...Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković. "Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic" in Energies, MDPI AG (2020)