In the paper a problem of determination of basic reliability parameters and characteristics for a system of pair of elements is considered. Different methods of operation of the system are discussed, however one method was chosen for further analysis as the most convenient one from practical point of view. It was presumed that the system operates following semi-Markov scheme. Basing on that presumption reliability characteristics were constructed and the steady-state availability of the system as well. Because the system consisted of two elements only, Authors indicated that it will be convenient to consider a system of two identical series systems operating in parallel with stochastically equal utilization.
Opto-mechatronic systems enable one to conduct long-term fatigue tests where the observation of the surface of the specimen and the monitoring of cracking process are required. The rapid advancement of opto-mechatronic technologies and the functional interaction between opto-electronic and mechatronic components indicate that design and implementation processes of opto-mechatronic systems require specific methodology. The presented methodology describes and considers the interactions between components, particularly inside the vision module. The design process can be supported by simulation models, databases, decision matrices, and the method of conducting the implementation maturity assessment of innovative technological solutions.
This article presents issues related to the construction of a computer-aided system evaluation of the technical condition of rail-vehicle wheel sets. Physical features which make a diagnostic feature vector are discussed and classified in the paper. This vector may be used for the identification of a vehicle condition state. Examples of formulas for distinguishing the classes of the technical states of rail-vehicles based on the evaluation of the thickness of a rim and the thickness and height of a wheel flange have been specified. The article also presents the guidelines for building a database for the computer-aided evaluation system of wheel sets.
Due to the nature of tasks performed by an aircraft, one of the most essential criteria determining the quality of its maintenance process is the reliability of devices and systems installed on an aircraft. The assurance of the reliability of aircraft devices at an adequately high level minimises the causes of failures. Unfortunately, the influence of destructive factors connected, among other things, with the impact of changing ambient conditions, overload effects, and the influence of ageing processes, causes the technical parameters of devices deteriorate. Methods for describing diagnostic parameter changes due to the effects of destructive factors have been presented in the literature [6, 7, 8, 9, 11]. This article constitutes a new attempt of an analytical description of the changes in diagnostic parameter values describing the technical state of devices based on the method
This article is a continuation of the consideration in the study Semi-Markov process for a pair of elements,” published in 2011. However, this paper discusses the issues concerning a multi-element symmetric pair and not just a pair of elements alone. The problems with the operation of this type of system are identified and discussed. An analysis of this multi-element system was done with a proposed modelling method of its operation. The presented methods take into account different cases, depending on the result of an empirical study, exactly the type of probability distributions of times of elements states which the system are composed. The modelling method provides solutions that allow the basic reliability parameters of the multi element system to be obtained.
This article presents an attempt at an analytical description of technical state changes within a selected group of technical objects. The occurring changes of the technical state of these objects are identified by diagnostic parameter values. The changes are identified by diagnostic parameter values. The technical state of a device deteriorates with the time of its maintenance due to the effect of numerous destructive factors. The conducted studies are based on the assumption that the intensity of changes of the deviation of diagnostic parameter values adopts the Weibull constants. The dynamics of changes of diagnostic parameter values is described by the difference equation that was transformed into a differential equation. Its solution in the form of a density function enables one to determine the reliability of a device in terms of an examined diagnostic parameter. The density function of the time of exceeding the limit state by a diagnostic parameter was determined using material from the literature [9], whose continuation is this article.
S u m m a r y This paper presents a method for determining the acceptable limits of piping vibration and their natural frequency. Acceptance criteria for the vibration values are taken as the limit of the allowed deformations of the pipeline caused by these vibrations and the limit of stress caused by these deformations. On the base of document The Pipeline and Compressor Research Councils, under the title Controlling the effect of pulsation and Fluid Transients in Piping Systems” a computer program setting these values based on given piping parameters was developed.
The concept of national innovation systems (NIS) appears to be an attractive idea on the grounds of policymaking, as it is expected to provide straightforward measures to boost a state’s competitive advantage. This paper presents Israel’s system of innovation with the main trends of its development, as well as key agents and linkages which shape their relationships. The study forms the basis for a question of NIS transferability and adaptability, and it demonstrates considerable limitations of the NIS emulation in different environments and economic settings, pointing to the evolutionary and country-specific characteristics of the innovation system. The unit of the analysis has been chosen due to the outstanding achievements of Israel in the field of innovation, strongly embedded in the unique attributes of the state, hence, being a particularly illustrative case for the study.
