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  • Author: Józef Żurek x
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Abstract

The paper has been intended to present models of intervention actions launched by the rescue system and undertaken by a team carried by a means of transport. The models are expected to simulate how the undertaken actions are performed. This, in turn, would allow the assessment of crew/team’s readiness to perform/accomplish the expected tasks within some fixed limits of time. Distinguished and described is a method to analyse intervention actions by rescue teams. General classification of tasks and the question of how stress affects the time to complete these tasks have also been included. An algorithm has been given to assess the process of mobilising teams for rescue actions. Furthermore, models of various intervention-action structures under crisis conditions have been presented. What else the paper submits is a method to assess reliability of an engineered means of rescue. The basis for the assessment is formed by a change of a selected diagnostic parameter. The main objective of this method is to search for the distribution of time to a failure of some specific type, characteristic of the object/device and operating conditions given consideration.

Probabilistic Methods for Assessment of Hazard in Transportation Systems

In this paper there has been presented destruction estimation models of construction elements of aircraft in different cases of the state of readiness. The following cases have been examined:

- when a diagnostic parameter indicating the state of readiness exceeds critical point

- when unexpected failure occurs as a result of overload impulse

- when a diagnostic parameter increases and as a result premature failure occurs

- when damage can be indicated with a diagnostic parameter and an unexpected failure may occur.

Differential calculus of Fokker-Planck type has been used in the model creating.

Abstract

An important part of the air base logistic system is the supply sub-system. In military operations the main delivery can be focused on munitions and aviation fuel. Effective management of the supply stream and the reliability of vehicles in the air base logistic system affect the quality of operations, which can be measured by on time provisions, economic factors and the reliability of vehicles. At present the number of tankers in the air base logistic system is based on experiences.

Problems of Safety in Aviation

The article describes the flight safety problems. It details a set of factors shaping the flight safety and activities required to maintain the requisite safety level. Attention has been paid to the need for rational safety management, including event history, risk assessment and risk cause investigation. Summary contains conclusions from the analysis of the flight safety status in transportation aviation.

The Aging-Processes-Based Forecasting of Service Lives of Selected Items of Aircraft Equipment

The paper has been intended to present a method of evaluating reliability and service lives of aircraft-equipment items. The evaluation has been based on the description of aging processes that take place throughout aircraft operational phase. What plays the most essential role in this method is the relationship that describes variations in a diagnostic parameter assumed to be a measure of changes in the condition of a given item due to aging processes. The Fokker-Planck equation has been used to describe these variations in the diagnostic parameter. The presented method may be used to control the operational phase of aeronautical devices.

Abstract

The reliability of thermal energy meters is analysed using the Markov model which describes the operation of these meters in a large number of apartments and offices by a media accounting company. The data has been extracted from a relational database storing information on the operation, installation and exchange of these measures from the last 10 years. The built Markov model turned out to be ergodic, which allowed determining its limiting distribution. In addition, the probability distributions for the cumulated consumption were determined in the work - separately for all meters and meters’ failures.

Damage Hazard Model for Chosen Element of the Aircraft Structure Taking Into Account Fatigue Crack Development Stages

The subject of the present paper is the modeling of aircraft structure fatigue processes which endanger flight safety. It is assumed that the simple course of the process of aircraft structure elements fatigue encompasses the following stages: initiation of cracks, crack development to the limit value, destruction of the element of structure. These stages can be taken as random incidents or random processes. The paper provides a description of the two initial stages as random processes. The relations obtained allow to define the reliability of the structure element and to evaluate the damage hazard in given time period.

Engineering System Reliability State Identification Methodology

In the process of investigating physical aspects of failures there is a need for measuring various features of objects. For this purpose measuring system, which consists of: operator - measuring instrument was used. In the paper an attempt of determining affectivity of such system was done. Influence of the first and second type errors on affectivity of the measuring system was considered. It was also shown how to decrease these errors. Influence on the affectivity of the reliability measurement of the measuring instrument was analyzed. Graduate and immediate failures were considered. Then some final conclusions were formulated.

Aging Processes as a Primary Aspect of Predicting Reliability and Life of Aeronautical Hardware

The forecasting of reliability and life of aeronautical hardware requires recognition of many and various destructive processes that deteriorate the health/maintenance status thereof. The aging of technical components of aircraft as an armament system proves of outstanding significance to reliability and safety of the whole system. The aging process is usually induced by many and various factors, just to mention mechanical, biological, climatic, or chemical ones. The aging is an irreversible process and considerably affects (i.e. Reduces) reliability and life of aeronautical equipment.

Abstract

In the article the process of operating a set of aircraft put into service at one time is examined. In order to maintain a balanced ratio ready to use and avoid the accumulation of hangar's maintenance, analysed transient process operation determining the probability of objects reside in different operating states. An interesting issue is change of a readiness as dependence of the model of adopted qualification. The main result of this article is the value of the probability of being ready to use. The probability of reaching the limit value is assuming different depends on initial conditions and different models of the probability density distributions. The results indicate the need for further testing of models of probability distributions to determine the optimal method qualifications or technical object is in standby mode or not.