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EN
Anticipatory Failure Determination (AFD) is a tool used in the TRIZ (Theory of Inventive Problem Solving) methodology. This article introduces its concept and describes the process of AFD in different versions of the method. The article presents the application of the AFD method at a very early state of a system’s development, i.e. its concept formulation stage, which corresponds to a technology readiness level (TRL) equal to 2. The system under analysis is a set of devices used to reduce displacement ship hull resistance. The system was modelled using functional analysis. An analysis of system resources was then carried out. Possible direct, indirect, and accident-related failures were identified. A multi-criteria analysis of the causes of system failures was conducted from which the top 10 potential failures were selected. Observations were made on the applicability of AFD in respect to systems not yet implemented.
EN
Today’s companies are able to automate the enforcement of Environmental, Health and Safety (EH&S) duties through the use of workflow management technology. This approach requires to specify activities that are combined to workflow models for EH&S enforcement duties. In order to meet given safety regulations these activities are to be completed correctly and within given deadlines. Otherwise, activity failures emerge which may lead to breaches against safety regulations. A novel domain-specific workflow meta data model is proposed. The model enables a system to detect and predict activity failures through the use of data about the company, failure statistics, and activity proxies. Since the detection and prediction methods are based on the evaluation of constraints specified on EH&S regulations, a system approach is proposed that builds on the integration of a Workflow Management System (WMS) with an EH&S Compliance Information System. Main principles of the failure detection and prediction are described. For EH&S managers the system shall provide insights into the current failure situation. This can help to prevent and mitigate critical situations such as safety enforcement measures that are behind their deadlines. As a result a more reliable enforcement of safety regulations can be achieved.
EN
The scope of the article includes the analysis of the gas network failure based on a material obtained from field tests covering the years 2004-2014, conducted on the gas network of 120 thousand city, allowing to specify the failure rate of the gas network with division into material, pressure and pipelines diameter and indicate the main causes of failure on gas networks. On the base of the results of this analysis the Monte Carlo method to predict failures in gas pipe network has been presented.
PL
Artykuł swoim zakresem obejmuje analizę awaryjności sieci gazowej na podstawie uzyskanego materiału z badań eksploatacyjnych obejmujących lata 2004-2014 prowadzonych na terenie Zakładu Gazowniczego w 120 tys. mieście, co pozwoliło na podanie intensywności uszkodzeń sieci gazowych z podziałem na materiał, ciśnienie i średnice rurociągów oraz podanie głównych przyczyn powstawania awarii na sieciach gazowych. Na podstawie wyników analizy zaprezentowano zastosowanie metody Monte Carlo do prognozowania awarii sieci gazowych.
EN
Sustaining high operational efficiency of a machine park requires the use of state-of-art solutions that support both monitoring of residual processes and performing thorough analysis of thereby collected data. What meets the needs of entrepreneurs who strive for high reliability of technological infrastructure is a modern approach to maintenance prediction. The literature of the subject offers numerous studies presenting the use of various statistical models for time series prediction. The objective of this paper is to verify whether tests used in econometrics such as the augmented Dickey-Fuller test and the Kwiatkowski-Phillips-Schmidt-Shin test are suitable for failure prediction. The simulations were performed for one diagnostic parameter, i.e. temperature.
PL
Utrzymanie wysokiego poziomu efektywności eksploatacyjnej parku maszynowego wymaga stosowania nowoczesnych rozwiązań wspierających monitorowanie procesów resztkowych i poddawania szczegółowej analizie uzyskanych w ten sposób informacji. Naprzeciw oczekiwaniom przedsiębiorców dotyczących utrzymywania wysokiego poziomu niezawodności infrastruktury technicznej wychodzi nowoczesne podejście w obszarze gospodarki remontowo-konserwacyjnej, jakim jest predyktywne utrzymanie ruchu. W literaturze przedmiotu wielokrotnie prezentowano wykorzystanie różnych modeli statystycznych pozwalających na prognozowanie wartości szeregów czasowych. Celem niniejszej pracy było sprawdzenie czy stosowany w ekonometrii rozszerzony test Dickeya-Fullera oraz test Kwiatkowskiego, Phillipsa, Schmidta i Shina mogą zostać użyte do predykcji zdarzeń niepożądanych jakimi są awarie. Symulację przeprowadzono dla wartości jednego parametru diagnostycznego jakim była temperatura.
EN
This article presents and assesses 64 different ways for predicting the failure onset in knotty wooden beams. The aim is to provide engineers and modellers a general view of how to evaluate the failure in wooden structural members with knots. The studied criteria included both the conventional point-based and average stress theories. Special attention was paid to the effect of the elements of the wood mesostructure, i.e. knots and fiber deviation, which can generate singular stress concentrations as notches or cracks would do in fracture mechanics. The case study consisted of predicting the failure onset of bending in structural wooden beams. A previously validated finite element model was used in order to compute the heterogeneous stresses. It was found that the knots caused considerable stress singularities so that the size of the average stress theory influenced the failure predictions by up to 23%. However, the variations generated by distinct phenomenological criteria were in general much smaller. The application of the average stress theory in large stress integration volumes is strongly recommended when predicting the failure in wood members.
PL
Uproszczony cieplny model kabla o nazwie THIEF, znajdujący zastosowanie w przewidywaniu czasu do zwarcia spowodowanego zewnętrznym czynnikiem termicznym, został ostatnio dołączony do kodu kilku znanych programów służących do dynamicznego modelowania rozwoju pożaru. Niniejszy artykuł przedstawia sposób takiego modelowania w programie ATP/EMTP. Umiejętność predykcji czasu do zwarcia określa margines bezpieczeństwa pozwalający uniknąć ich nieprzewidywalnych skutków, groźnych zwłaszcza w elektrowniach atomowych.
EN
Simplified thermal model of cable exposed to external heat flux hazard, called THIEF, used for predicting the failure time has been recently implemented in the code of a few programs used for dynamic fire simulation. The paper presents the way of modeling in program ATP/EMTP. The prediction of shorting time determines the safety margin to avoid the unpredictable consequences, especially dangerous in nuclear power plants.
EN
The proactive maintenance is an effective approach to enhance the system availability through real time monitoring the current state of a system. The key part of this method is forecasting the nonoperational states for advanced warning of the failure possibility that can bring the attention of machines operators and maintenance personnel to impending danger facilitate planning preventive and corrective operations, and resources managing as well. The paper presents the HMI/SCADA-type application used to support decision-making process. The proposed approach to proactive maintenance is based on forecasting the remaining useful life of device equipment and delivering the user-defined maintenance strategy developed during system operation. The HMI/SCADA application is used to collect data in form of failures history, changes of operational conditions and performances of a monitored process between failures, as well as heuristic knowledge about process created by experienced user. The data history is used to design the predictive fuzzy models of time between failures of system equipment. The fuzzy predictive models are designed using the genetic algorithm applied to optimize the fuzzy partitions covering the training data examples, as well as to identify fuzzy predictive patterns represented by a set of rules in the knowledge base. The evolutionary learning strategy, which has been proposed in this paper, provides the effective reproduction techniques for searching the solution space with respect to optimization of knowledge base and membership functions according to the fitness function expressed as a ratio of compatibility of fuzzy partitions with data examples to root mean squares error. The proposed application was created and tested on the laboratory stand for monitoring the availability of the overhead travelling crane.
EN
The classic approach to evaluate the probability that an operational system is capable to operate satisfactorily and successfully perform the formulated tasks is based on availability that is coefficient which is determined based on the history of down-time and up-time occurring, while the risk-degree of down-time occurring strongly depends on the actual operational state of a system. The intelligence computational methods enable to create the diagnosis tools that allow to formulate the prognosis of operating time of a system and predict of failure occurring based on the past and actual information about system's operational state, especially genetic fuzzy systems (GFSs) that combine fuzzy approximate reasoning and capability to learn and adaptation. The paper presents the fuzzy rule-based inference system used to predict the operating time of exploitation system according to the specified operational conditions. The proposed algorithm was used to design the fuzzy model applied to estimate the operating time of a system between the actual time and predicted time of the next failure occurring under the stated operational parameters. The fuzzy system allows to prognoses the time of the predicted failure based on the operational parameters which are used to evaluate the actual operational state of the system. The attention in the paper is focused on the evolutionary computational techniques applied to design the fuzzy inference system. The paper proposes the genetic algorithm based on the Pittsburgh method and real-valued chromosomes used to optimize the knowledge base and parameters of antecedents and conclusions of the Takagi-Sugeno-Kang (TSK) fuzzy implications. The paper is the contribution to the GFSs, which aim is to find an appropriate balance between accuracy and interpretability, and also contribution to the research field on the diagnosis methods based on soft computing techniques. The evolutionary algorithm was tested for designing the fuzzy operating time predictor of material handling device.
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