scholarly journals Assessment of an Anomaly Detector for Jet Engine Health Monitoring

2011 ◽  
Vol 2011 ◽  
pp. 1-11
Author(s):  
Sebastien Borguet ◽  
Olivier Léonard
Keyword(s):  
Adaptive Estimation ◽  
Aircraft Engine ◽  
Ratio Test ◽  
Secondary System ◽  
Auxiliary Component ◽  
The Face ◽  
Anomaly Detector ◽  
Diagnosis Tool ◽  
Main Components ◽  
Module Performance

The goal of module performance analysis is to reliably assess the health of the main components of an aircraft engine. A predictive maintenance strategy can leverage this information to increase operability and safety as well as to reduce costs. Degradation undergone by an engine can be divided into gradual deterioration and accidental events. Kalman filters have proven very efficient at tracking progressive deterioration but are poor performers in the face of abrupt events. Adaptive estimation is considered as an appropriate solution to this deficiency. This paper reports the evaluation of the detection capability of an adaptive diagnosis tool on the basis of simulated scenarios that may be encountered during the operation of a commercial turbofan engine. The diagnosis tool combines a Kalman filter and a secondary system that monitors the residuals. This auxiliary component implements a generalised likelihood ratio test in order to detect abrupt events.

A Generalised Likelihood Ratio Test for Adaptive Gas Turbine Health Monitoring

2008 ◽  
Author(s):  
S. Borguet ◽  
O. Le´onard
Keyword(s):  
Kalman Filter ◽  
Likelihood Ratio ◽  
Likelihood Ratio Test ◽  
Health Monitoring ◽  
Aircraft Engine ◽  
Ratio Test ◽  
Secondary System ◽  
Commercial Aircraft ◽  
Turbine Engine ◽  
Auxiliary Component

Kalman filters are widely used in the turbine engine community for health monitoring purpose. This algorithm has proven its capability to track gradual deterioration with a good accuracy. On the other hand, its response to rapid deterioration is either a long delay in recognising the fault, and/or a spread of the estimated fault on several components. The main reason of this deficiency lies in the transition model of the parameters that is blended in the Kalman filter and assumes a smooth evolution of the engine condition. This contribution reports the development of an adaptive diagnosis tool that combines a Kalman filter and a secondary system that monitors the residuals. This auxiliary component implements a Generalised Likelihood Ratio Test in order to detect and estimate an abrupt fault. The enhancement in terms of accuracy and reactivity brought by this adaptive Kalman filter is highlighted for a variety of simulated fault cases that may be encountered on a commercial aircraft engine.

scholarly journals A Generalized Likelihood Ratio Test for Adaptive Gas Turbine Performance Monitoring

2008 ◽  
Vol 131 (1) ◽  
Author(s):  
S. Borguet ◽  
O. Léonard
Keyword(s):  
Kalman Filter ◽  
Likelihood Ratio ◽  
Likelihood Ratio Test ◽  
Performance Monitoring ◽  
Aircraft Engine ◽  
Generalized Likelihood Ratio Test ◽  
Ratio Test ◽  
Secondary System ◽  
Generalized Likelihood Ratio ◽  
Auxiliary Component

Kalman filters are widely used in the turbine engine community for health monitoring purposes. This algorithm has proven its capability to track gradual deterioration with good accuracy. On the other hand, its response to rapid deterioration is a long delay in recognizing the fault and/or a spread of the estimated fault on several components. The main reason for this deficiency lies in the transition model of the parameters that is blended in the Kalman filter and assumes a smooth evolution of the engine condition. This contribution reports the development of an adaptive diagnosis tool that combines a Kalman filter and a secondary system that monitors the residuals. This auxiliary component implements a generalized likelihood ratio test in order to detect and estimate an abrupt fault. The enhancement in terms of accuracy and reactivity brought by this adaptive Kalman filter is highlighted for a variety of simulated fault cases that may be encountered on a commercial aircraft engine.

scholarly journals Modern Approaches and Methods in Teaching English

2020 ◽  
pp. 63-66
Author(s):  
Marina Anatolevna Sinovats
Keyword(s):  
Foreign Language ◽  
New Technologies ◽  
Traditional Education ◽  
Educational Process ◽  
Human Potential ◽  
Educational Institutions ◽  
Innovative Methods ◽  
The Face ◽  
Recent Trends ◽  
Main Components

Teaching a foreign language includes two main components: to impart and to receive information. In practice, the teacher tries his best to convey the knowledge that he has. The use of innovative methods in educational institutions expands the rights and opportunities of both students and teachers. Innovative technologies contribute to the development of the country's human potential. With a number of educational opportunities available to students of the modern generation, new trends that have completely changed the face of the traditional education system have emerged. Recent trends in the methodology reflect the vitally important role of the education sector as a whole, with its internalization of the educational process, emphasis on quality, and increased use of new technologies. Theory and methods are constantly being developed in the field of ELT. The article presents well-known trends in ELT that have been practically used all over the world recently. New trends in foreign language teaching are becoming known as GTM, a communicative method.

Tourist profiles and attitudes: a comparison between cities in a different phase of the life cycle

2019 ◽  
Vol 6 (4) ◽  
pp. 731-748
Author(s):  
Josep-Francesc Valls Giménez ◽  
Gina Pipoli ◽  
Paulo Rita ◽  
Itziar Labairu-Trenchs
Keyword(s):  
Factor Analysis ◽  
Life Cycle ◽  
Design Methodology ◽  
Universal Model ◽  
Content Type ◽  
City Culture ◽  
The Face ◽  
Advanced Stages ◽  
Main Components ◽  
The City

Purpose The purpose of this paper is to analyse the different typologies of tourists that appear in cities that are in a different position within the destination life cycle. Barcelona and Lisbon, two urban destinations, with a strong growth of tourists in the last two decades, which are in advanced stages of their life cycle, and Lima, which has also expanded in the last ten years, but is in less advanced phases, have been chosen. The approach of the study is to analyse if urban tourists modify their attitude in some way in the face of the advancement of the life cycle of the city and what attitudes are expressed by them. Design/methodology/approach For this purpose, an analysis of main components was performed via factor analysis to reduce the number of dimensions of the 11 descriptive variables and the counterpart of tourist attitudes, following Schwartz’s (2006) research. From the four clusters that emerged – authenticity; innovative and cultural hard; relaxation and not innovative – four attitude variables were selected since they were considered relevant to be analysed according to the life cycle of the city: culture and entertainment; authenticity and online social exhibition; and expensive and cheap price. Findings The results obtained do not allow to straightforwardly conclude that as the life cycle of these three cities advances, the attitude evolves from culture to entertainment, from authenticity towards online social exhibition or from the most expensive to the cheapest. The tourists from Barcelona are mostly associated with entertainment, those from Lisbon are associated with culture and those from Lima are split. However, in the face of authenticity, travellers are prone to it. Regarding the price, those in Barcelona are almost divided equally, whereas those in Lisbon, and especially those in Lima, consider it to be mostly cheap. Originality/value From this study, it can be drawn that the attitude of travellers to these three cities is not conditioned by the life cycle. Globalization and digitalisation put pressure on the traveller by configuring a universal model of behaviour before the urban offer that is associated with other factors, but not with the life cycle of the city.

Design and Realization of Total Performance Simulation Platform for Aircraft Engine Based on Modelica

2013 ◽  
Vol 404 ◽  
pp. 324-330
Author(s):  
Gao Xiang Chen ◽  
Jiang Fan
Keyword(s):  
Aircraft Engine ◽  
Mathematic Model ◽  
System Level ◽  
Generic Model ◽  
Preliminary Design ◽  
Performance Simulation ◽  
Model Library ◽  
Level Model ◽  
System Level Model ◽  
Main Components

The primary characteristics of Modelica language is described, The steady and dynamic mathematic model of aircraft engine are introduced. The methods of the main components in the aircraft engine generic model library developed by Modelica/Dymola software are expounded. The system level model of a two-spool turbofan engine is built and its steady and off design state is simulated. The results accord with the actual situations, so that the library can help in constituting the simulation system of variety engine with great importance and practical value in conceptual and preliminary design.

Evaluative prosodies in academic quality audit reports

2016 ◽  
Vol 23 (3) ◽  
pp. 336-360 ◽  
Author(s):  
Victor Ho
Keyword(s):  
Quality Assurance ◽  
Hong Kong ◽  
Appraisal Theory ◽  
Academic Quality ◽  
Quality Audit ◽  
The Face ◽  
Evaluative Language ◽  
Main Components ◽  
Audit Reports ◽  
The University

This paper analyzes the discourse of academic quality audit reports by drawing upon Appraisal Theory (Martin & White 2005). It focuses on the evaluative prosodies in the discourse leading up to the three main components of the reports, namely commendations, affirmations, and recommendations. These reports are prepared by the audit panels formed by the Quality Assurance Council of the University Grants Committee of Hong Kong upon the completion of academic quality audit visits to each of the city’s eight publicly-funded tertiary institutions. This paper argues that such evaluative prosodies, or the pattern of use of evaluative language, are strategically employed by the audit panels in an attempt to strike a balance between three needs: (1) to discharge their quality assurance responsibilities with their power vested by the Hong Kong Government through the University Grants Committee; (2) to maintain and/or reinforce a credible ethos for the panels themselves; and (3) to attend to the face wants of the institutions and the stakeholders concerned.

scholarly journals Adaptive Estimation Algorithm for Aircraft Engine Performance Monitoring

2008 ◽  
Vol 24 (4) ◽  
pp. 763-769 ◽  
Author(s):  
Olivier Léonard ◽  
Sébastien Borguet ◽  
Pierre Dewallef
Keyword(s):  
Performance Monitoring ◽  
Adaptive Estimation ◽  
Engine Performance ◽  
Aircraft Engine ◽  
Estimation Algorithm

scholarly journals Experimental Analysis of the Influence of the Application of TiN, TiAlN, CrN and DLC1 Coatings on the Friction Losses in an Aviation Internal Combustion Engine Intended for the Propulsion of Ultralight Aircraft

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6839
Author(s):  
Piotr Wróblewski ◽  
Robert Rogólski
Keyword(s):  
Combustion Engine ◽  
Aircraft Engine ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Maximum Pressure ◽  
Working Medium ◽  
The Moment ◽  
Main Components ◽  
Moment Of Resistance ◽  
Wear Coatings

Currently, there are many methods of reducing the friction losses of the main components of an internal combustion piston engine. The operating conditions of internal combustion piston engines intended for the propulsion of ultralight aircraft differ significantly from those prevailing in the case of using these engines for the propulsion of vehicles. There are many studies on the influence of selected anti-wear coatings on the friction coefficients when using various lubricants, measured via tribometers. Unfortunately, the conditions obtained in the laboratory significantly differ from those prevailing in an engine operating under external conditions. The study investigated the influence of a change in the tribological parameters of TiN, TiAlN, CrN and DLC1 anti-wear coatings on the moment of resistance to the piston movement of an aircraft engine. The operating parameters of a real engine working in an aircraft were simulated. The main focus was on the coating layers of the sliding surfaces of the piston rings and the cylinder running surface. The properties of the coatings affect the correlation of the scale of the adhesion and cohesion phenomena of the oil to the opposite planes, and this determines the nature of the changes in the moment of resistance to engine motion. As it is commonly known, with an increase in the value of the maximum pressure of the working medium in the combustion chamber, the share of mixed friction in liquid friction increases, similar to the high oil temperatures occurring in aircraft engines. Therefore, there is a justified need to supplement the research in the field of analyzing the characteristics of the torque of resistance to motion for these engines, in particular in the field of the usable rotational speeds of the crankshaft. Applicable anti-wear systems based on selected coatings can significantly improve operational safety and noticeably reduce fuel consumption.

scholarly journals FINANCIAL SECURITY OF THE REGION: SCIENTIFIC APPROACHES TO THE IDENTIFICATION OF THE CONCEPT

2020 ◽  
Vol 288 (6) ◽  
pp. 73-77
Author(s):  
Y. NIKOLCHUK ◽  
Keyword(s):  
Economic Security ◽  
Security System ◽  
National Currency ◽  
Effective Control ◽  
Financial Security ◽  
Self Development ◽  
The Face ◽  
System Variability ◽  
Main Components ◽  
State Saturation

Ensuring financial security at all levels of government is an important task for many countries, including Ukraine. It is impossible to solve the economic problems facing the country, region and enterprise without providing them with financial security. This task is becoming a particular priority in the face of instability and financial crisis. The purpose of the article is to generalize the theoretical provisions on the essence of financial security of the regions, to identify its main components and areas of support. The article presents the interpretation of the concept of the region in the framework of different approaches of scientists. The most important blocks of the structure of economic security of the region are revealed: financial independence, stability and stability of the regional economy, ability to self-development and progress. The main approaches to the essence of the concept of “financial security” are systematized, the essence of the concept of “financial security system of the region” is considered. The principles of economic security of the region are given: general, namely: complexity, system, variability (alternatives), the principle of coordination (coordination) of relations and relations of all elements of economic security of the region, the principle of specialization elements (separation of functions and operations performed by elements). Based on the obtained results, the directions of strengthening the financial security of the region are proposed. In the current conditions of economic development of Ukraine, first of all it is necessary to move in the direction of improving the system of financial security, namely: establishing the boundaries of foreign participation in the capital of domestic organizations; introduce industry restrictions; development of effective control systems for attracting and using foreign borrowings. We believe that the country’s financial security system should ensure the solution of the following tasks: creating a full-fledged national currency and maintaining it in a stable and competitive state; saturation of the economy and the market with money supply in the amount necessary for their full functioning and development; creation of conditions provide intensive formation of competitive national financial capital denominated in national currency; ensuring financial parity with Ukraine’s main competitors in the medium term.

scholarly journals Dialogical Structure Experience in Basic Design Studio at Online Education

2021 ◽  
Vol 3 (2) ◽  
pp. 261-270
Author(s):  
Derya Adiguzel Ozbek ◽  
Keyword(s):  
Online Education ◽  
Design Studio ◽  
Basic Design ◽  
Sharp Transition ◽  
Face To Face ◽  
The Face ◽  
Main Components

In this study, the structure of the basic design studio that started with face-to-face education and had to end with online education due to the COVID-19 pandemic, which was set over Bakhtin's dialogic concept, is discussed. The three main components of the basic design studio; studio space, studio process and studio content and the combination of these components have changed in the transition from face-to-face education to online education. With these changes, dialogic relations are defined in the basic design studio's setup that extends from the face-to-face to the online education, and a structure that is shaped not as a sharp transition but as a flow has been developed. The basic design studio structure, which is shaped by the concept of dialogue, is presented as an approach proposal for online education, which is still ongoing and is expected to continue.

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