Fuzzy Identification of The Reliability State of The Mine Detecting Ship Propulsion System

Abstract

The study presents the evaluation and comparative analysis of engine shaft line performance in maritime transport ships of the same type. During its operation, a technical system performs functions for which it was designed. It goes through different states. Dynamic state changes of a rotational system can be identified by means of its vibration measurement. For this purpose, a research was carried out which involved recording vibrations of the analysed rotational systems. The recordings were used for calculating selected characteristics in the time-domain, where one of the most unique is the value of the normalized mutual correlation function. On the basis of the concentration values, the characteristics which unambiguously determine the ability state were selected for further studies. Then an identification method for rotational system non-coaxiality was proposed. The method involves using fuzzy clustering. According to this method the values of input signal characteristics were used to formulate fuzzy clusters of system ability and inability states. The method can be used for identifying the current state of the system. The study presents the results of the application of this method in engine turbine shaft lines of minesweepers, with the rotational system selected as an example. It needs to be noted that the efficiency of identifying the operating state of the system with this method is higher than with other methods described in the literature by authors who deal with this issue. The research results have a significant impact on the evaluation of mechanical properties of the studied objects and directly affect operational states of mechanical systems, including those installed in minesweepers, thus determining their reliability.

The Impact of Powering an Engine with Fuels from Renewable Energy Sources including its Software Modification on a Drive Unit Performance Parameters

“…An analysis of the state of knowledge in the studied area shows that the use of biofuels to power self-ignition engines causes reduction of exhaust emission components discharged to the natural environment [28,[40][41][42][43][44][45][46][47][48][49][50]. The tests of real transport objects for the engine factory settings confirm power and torque decrease and reduction in the amount of exhaust components [9,43,44,[49][50][51][52][53][54][55][56][57]. The literature provides no information on the research into internal combustion engines powered with diesel oil and fatty acid methyl esters in different proportions for different fuel injection controller settings, nor an adequate model for an assessment method of the impact of use of biocomponent additive in diesel oil.…”

Towards Developing an Automated Faults Characterisation Framework for Rotating Machines. Part 1: Rotor-Related Faults

“…Supervised learning is a specific machine learning category, whereby an algorithm can either learn a pattern or build a model (function) using labelled training data, and subsequently infer new instances based on such earlier learned patterns or models [33][34][35][36][37][38][39]. Solving a specific supervised learning problem requires the following various steps including; data type determination, training dataset collection, input features determination, learning algorithm determination, adjustment of the learning algorithm parameters and learning accuracy evaluation.…”

“…2.4.3. Support Vector Machine (SVM) SVM constructs a hyperplane or a set of hyperplanes, in high or infinite-dimensional space, which can be used for classification, regression or other tasks [34,39]. The generalisation error of this classifier can be best reduced when the classification boundary is far away from the nearest training data points.…”

Impact of changes in the fuel injection controller settings on the power and torque performance depending on the engine speed

“…The twentieth century was a breakthrough in petroleum extraction and refining which made it the fastest developing branch of industry [3,4]. Deposits of sticky crude oil are sought by geologists and obtained through wells in a 1-kilometer deep soil, for which mining statistics are needed [5]. Advantages of fuels designed for these engines are their good lubricating properties, lower viscosity and high octane number which indicates the engine ability to self-ignite.…”