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The paper presents the possible applications of using acoustic diagnostics in inspecting the technical condition of an internal combustion engine with autoignition on the example of the Fiat drive unit with common rail system. As a result of measuring the sound pressure level for specific faults and comparing the noise generated by the motor running smoothly, the detailed maps of changes in the acoustic spectrum are possible to generate. These results may be helpful in the future diagnostics of internal combustion engines. In the paper, the results of scientific work in the area of research, design and operation of internal combustion engines, conducted at the Department of Automotive Engineering, in cooperation with the Laboratory of Hydraulic Drives & Vibroacoustics of Machines at the Wroclaw University of Technology are included.

T he paper is a continuation of the publication under th e title "Acoustic diagnostics applications in th e study of technical condition of com bustion engine" and concerns th e detailed description of decision support system for identifying technical condition (type of failure) of specified com bustion engine. T he in p u t d a ta were m easured sound pressure levels of specific faults in com parison to th e noise generated by undam aged m otor. In th e article, the whole procedure of decision m ethod based on game graphs is described, as well as th e interface of th e program for direct usage. K e y w o rd s : gam e graphs; acoustic diagnostics; com bustion engine.

In the optimization process, changes in the construction parameters value influence the behaviour of functions depending on time. Weighting logical coefficients for the stabilisation time are taken into consideration here, i.e., a shorter (better) stabilisation time has a more important (bigger) value of the weighting coefficient. An example of applying weighting logical functions in the analysis of a degree of importance of construction parameters of a hydraulic valve is presented in the paper.

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This paper presents the way of identifying the influence of the tolerance of model pumps (TYPE 3PWR-SE) construction on the total efficiency. The identification of sensitive control dimensions (Value / Tolerance) of examined pumps has been made by means of the multi-valued logic and inductive decision trees. In order to confirm the obtained results, multiple-valued logic trees have been used in the paper according to algorithms for the minimization of individual logic functions.What is more, a specific monotonicity of values of the most key parameters has been determined for the investigated set of pumps having individual specification numbers.

With the development of engineering materials, as well as the growing requirements for weight reduction and the reduction of energy consumption by mechanical systems, attempts have been made to utilize composite materials in the design of hydraulic cylinders. In many cases, the reduction in the weight of the actuators may lead to a reduction in the values of bending moments acting on the booms of working machines, as well as leading to a reduction in the power demand in drive systems. The use of composite materials can also increase the reliability of cylinders in corrosive environments and places with strong electromagnetic fields. This paper presents the development of hydraulic actuators made of composite materials, presenting both the achievements of research centers and commercial companies. The main research and engineering problems are presented along with the methods of solving them resulting from the literature available. The directions for further research that should be undertaken in order to increase reliability, improve efficiency, and reduce weight are also outlined.

Previous applications of the graph theory concerned the modeling of gears for dynamic analysis, kinematic analysis, synthesis, structural analysis, gearshift optimization and automatic design based on so-called graph grammars. Some tasks can be performed only by using methods resulting from a graph theory, e.g. enumeration of structural solutions. The contour plot method consists in distinguishing a series of consecutive rigid units of the mechanism, forming a closed loop (so-called contour). At a later stage, it is possible to analyze the obtained contour graph as a directed graph of dependence. The work presents an example of the use of game-tree structures for describing the contour graph of a planetary gear. As a result of the decomposition of the graph in the dependence on each of the vertices, game-tree structures are obtained, which allow calculate algorithmically.