Wyniki wyszukiwania - Biblioteka Nauki

1

Interval-valued intuitionistic fuzzy failure modes and effect analysis of the system failure risk estimation

100%

Nguyen H.

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2017

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tom Vol. 24, No. 2

159--166

EN

Among the risk assessment methods, failure modes and effects analysis (FMEA) is a popular, widely used engineering technique in many areas. It can be used to identify and eliminate known or potential failure modes to enhance reliability and safety of complex systems. In practice, risk estimations encounter difficulties connected with shortage of data. In such cases, we have to rely on subjective estimations made by persons with practical knowledge in the field of interest, i.e. experts. However, in some realistic situations, the decision makers might be unable to assign the exact values to the evaluation judgments due to his/her limited knowledge. In other words, there is a certain degree of hesitancy in human cognition and his/her judgment, who may have insufficient knowledge of the problem domain or uncertainty in assigning the evaluation values to the objects considered. In order to deal with ambiguity and uncertainty in the imperfect information, there have been recently proposed many various such theories as fuzzy sets, interval-valued fuzzy sets, type-2 fuzzy sets, hesitant sets, grey sets, rough sets and intuitionistic fuzzy sets. They have drawn more and more attention of scholars and been adopted in many applications This article addresses the Atanassov’s interval-valued intuitionistic fuzzy sets and FMEA methods in the risk estimation of the system failures based on the expert judgments.

2

Data analysis and processing for the system reliability neural network based on expert judgment

86%

Nguyen H.

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tom Vol. 21, No. 2

235--242

EN

The article presents a data analysis and processing for tuning artificial neural network (ANN) of the anthrop technical system reliability, based on the opinions of experts. In general, the system reliability parameters are functions of operands – physical values – like time to failure, time between failures, duration times of specific reliability or operational states, number of failures in a time interval (event frequencies). These values are easier to be determined by an expert – operator with long year experience – than probabilistic model parameters. It is suggested that they be used in elicitation, for example linguistic estimates of the shares of reliability system elements in the system failure frequency. The numerical – linguistic elicitation of these opinions was carried out, which turned out to be uncorrelated and not suitable for tuning the network. Data processing method was used with the appropriate adopted analytic hierarchy process (AHP) geometric scale and matrix approximation method evaluations (logarithmic least squares method). Correlation analyses were performed for received input and output data of network and error of data processing method was determined. The results are shown in the example of elicitation and data correlation analyses for tuning the reliability neural network of the ship propulsion system.

3

An application of intuitionistic fuzzy analytic hierarchy process in ship system risk estimation

86%

Nguyen H.

Journal of KONES

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2016

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tom Vol. 23, No. 3

365--372

EN

In this paper, we extend the analytic hierarchy process (AHP) method and the Atanassov’s intuitionistic fuzzy set (IFS) into the intuitionistic fuzzy analytic hierarchy process (IFAHP) with application in ship system risk estimation. In the safety engineering, risk estimation is in practice confronted with difficulties connected with shortage of data. In such cases, we have to rely on subjective estimations made by persons with practical knowledge in the field of interest, i.e. experts. However, in some realistic situations, the decision makers might be reluctant or unable to assign the crisp evaluation values to the comparison judgments due to his/her limited knowledge. In other words, there is a certain degree of hesitancy in human cognition and his judgment. Taking advantages of IFSs in dealing with ambiguity and uncertainty into account, the IFAHP can be used to handle with the subjective preferences of experts, who may have insufficient knowledge of the problem domain or uncertainty in assigning the evaluation values to the objects considered. This paper also develops a new knowledge-based ranking method to derive the priority vector of the hierarchy. An illustrative example of the propulsion risk estimation of container carriers operating on the North Atlantic line is given to show the applicability and effectiveness of the proposed method.

4

Fuzzy methods in risk estimation of the ship system failures based on the expert judgments

72%

Hoang N.

Journal of KONBiN

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2017

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tom No. 43

393--403

EN

The paper presents the fuzzy methods in failure modes and effects analysis (FMEA) for estimating the risk of the ship system failures based on the expert judgments. It provides an appropriate representation of the uncertain and ambiguous notions expressed in the natural language. An example of fuzzy intuitionistic FMEA analysis is illustrated in estimating the risk of tanker system failures. The results show that the proposed method in comparison with the traditional FMEA is more effective and useful in estimating the risk of ship system failures based on the expert opinions, available in such cases.

PL

Praca przedstawia rozmyte metody w analizy rodzajów i skutków uszkodzeń (FMEA) do estymacji ryzyka uszkodzeń systemów okrętowych. Zapewnia ona odpowiednią reprezentację niepewnych i niejasnych pojęć wyrażonych w języku naturalnym. Przykład zastosowania rozmytej, intuicjonistycznej analizy FMEA został zilustrowany w estymacji ryzyka uszkodzeń systemów tankowca. Uzyskane wyniki wskazują, że proponowana metoda w porównaniu z tradycyjną analizą FMEA, jest bardziej skuteczna w estymacji ryzyka uszkodzeń systemów okrętowych, na podstawie opinii ekspertów.

5

Selection of construction enterprises management strategy based on the SWOT and multi-criteria analysis

58%

Zavadskas E. K. , Turskis Z. , Tamosaitiene J.

Archives of Civil and Mechanical Engineering

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2011

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tom Vol. 11, no 4

1063-1082

EN

The paper proposes a methodology for determining management strategies in construction enterprises. For this purpose, the SWOT (Strengths, Weaknesses, Opportunities and Threats) analysis as an instrument for formulating management strategies is recommended. The best practices for this reason are also analysed. The algorithm helps to select the most preferable strategies based on the AHP, expert judgment and permutation method of feasible alternatives. A perspective of construction enterprises management regarding the SWOT is carried out on a basis of selected description of the current state and the feasible future alternatives. Finally, the selected alternatives are ranked according to the permutation method of feasible alternatives. The case study shows the applicability of the proposed model to the real management problems solution.

PL

W pracy zaproponowano metodologie określania strategii zarządzania dla przedsiębiorstw budowlanych. W tym celu wykorzystywana jest analiza SWOT (mocnych stron, słabych stron, szans, zagrożeń) jako narzędzie służące do formułowania odpowiedniej strategii zarządzania. Algorytm pomaga wybrać najbardziej korzystną strategie opartą na AHP, ekspertyzie i metodzie permutacyjnej dla prawdopodobnych scenariuszy. Perspektywa zarządzania przedsiębiorstwem budowlanym w ujęciu SWOT jest przeprowadzana na podstawie wybranych opisów stanu aktualnego oraz przyszłych możliwych scenariuszy. Finalnie wybrane scenariusze są oceniane w oparciu o metodę permutacyjną. Studium przypadku pokazuje możliwości zastosowania proponowanego modelu do rozwiązywania rzeczywisty problemów zarządzania.

6

Strojenie sieci neuronowej niezawodności systemu na podstawie opinii ekspertów

58%

Brandowski A. , Nguyen H.

Zeszyty Naukowe Akademii Morskiej w Gdyni

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2014

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tom nr 83

5--20

PL

W artykule przedstawiono metodę strojenia sieci neuronowej, odpowiednią w analizach niezawodności systemów antropotechnicznych, opartą na opiniach ekspertów – praktyków eksploatacji. Przeprowadzono numeryczno-lingwistyczną elicytację tych opinii, które okazały się nieskorelowane i nie nadawały do strojenia sieci. Do przetwarzania danych zastosowano metodę AHP z odpowiednią przyjętą skalą i metodą aproksymacji macierzy ocen. Przeprowadzono analizy korelacji zbiorów otrzymanych danych wejściowych i wyjściowych sieci oraz uchybu metody przetwarzania danych. Wyniki przedstawiono w przykładzie elicytacji i analizy korelacji danych sieci niezawodności systemu napędowego statku morskiego.

EN

The article presents a method for tuning neural network, appropriate in the analysis of the anthrop technical system reliability, based on the opinions of experts – practitioners operation. The numerical-linguistic elicitation of these opinions was carried out, which turned out to be uncorrelated and not suitable for tuning the network. Data processing method was used with the appropriate adopted AHP scale and matrix approximation method evaluations. Correlation analyzes were performed for received input and output data of network and error of data processing method was determined. The results are shown in the example of elicitation and data correlation analyzes for tuning the reliability neural network of the ship propulsion system.