Tato práce se zabývá vývojem nového efektivního diagnostického postupu pro kontrolu funkce pneumatických válců pomocí metody akustické emise. Cílem práce bylo navrhnout a určit diagnostická kritéria pro hodnocení kvality vybraných typů pneumatických válců. Prvním krokem bylo nalezení typického akustického emisního signálu, který je spojen s určitým typem poškození ve válci využitím frekvenčního spektra signálu. Později byl tento parametr nahrazen parametrem RMS během sledování změn v průběhu testů. Na konkrétních válcích byl sledován vztah mezi akustickou emisí a různými typy defektů a byl představen nový přístup k určování těchto typů vad a jejich odlišením v signálu akustické emise. Druhý krok studie že neporušené a poškozené válce byly porovnávány tak, aby se zjistily výrazné rozdíly, které určují, zda je válec poškozen nebo nepoškozen. Několik nepoškozených válců bylo testováno akustickou emisí a následně v nich byly vytvořeny umělé vady. Signály z vysouvání a zasouvání pístu byly zaznamenány a analyzovány pomocí řady parametrů. Na základě časového zpoždění a normalizace RMS byly rozpoznány odezvy mezi poškozenými a nepoškozenými pneumatickými válci. Rozdíly byly zjištěny porovnáním maximální hodnoty RMS ze snímače upevněného na předním víku válce a snímače upevněného na zadním víku válce pro jeden cyklus. Poškozené a nepoškozené válce byly rozlišeny pomocí rozdílů energetických hodnot přítomných v signálech z obou snímačů v závislosti na zdvihu pístu. Konečné vyhodnocení válce bylo určeno výpočtem celkové hodnoty RMS. Ve třetím kroku experimentu byly válce postupně zatěžovány různými závažími ve svislém směru. Signály akustické emise byly zaznamenány z vysouvání a zasouvání pístu a poté analyzovány. Časové zpoždění se vypočítává z digitálního vstupu a začátku pohybu pístu. Energie signálu a RMS akustické emise porovnávají různé reakce v poškozených a nepoškozených pneumatických válcích s a bez zatížení. Výsledky testu ukázaly lineární vztah mezi křivkou RMS a zatížením. Defekty ovlivňují vztah mezi aplikovaným zatížením a zaznamenaným signálem snímačů.

Submitted diploma thesis deals about operational deformations in the cylinder unit of turbocharged diesel engine used in commercial vehicles. Introductory part analyses combustion engines computational modelling based on finite element method. The next step is the creation of computational models for thermal-structural analyses of the piston and engine block. In order to determine material characteristics of the head gasket, experiment is performed on the OEM gasket to determine its real behaviour under compressive load. The results shows strong nonlinear behaviour which justifies the decision of making such an experiment in the first place. The results of computational models are radial deformations of the piston and cylinder liners during load conditions. The last chapter deals with the application of these results to an advanced computational piston assembly dynamics model.

The work deals with the analysis of various possibilities of increasing the efficiency of a small internal combustion engine potentially usable for use in the field of autonomous devices of smaller dimensions. It contains an outline of the problems of modern smaller autonomous means and an analysis of available drives designed for them, especially an analysis of propulsion by internal combustion engines. In his next part of the work he provides information about the created mathematical model of the demonstration internal combustion engine in the GT-Power program and an analysis of places where and in what ways its efficiency can be increased. The design of two such components together with the evaluation of the achieved results offers the conclusion of this work.

The purpose of this work is identification with theory of EH antennas, do the simulation of one choice of model of EH antenna from literature and this model optimise on required frequency 14 MHz through the use of computer software CST Microwave Studio. The practical part of work is to produce choice model of EH antenna, to mete his properties and to verify use in real traffic. The EH antenna is an electromagnetic electrically short antenna, which can work as a transmitting or receiving antenna. The main characteristic of EH antenna is distributed radiating electromagnetic field, whose electric component E and magnetic component H are mutually crossed and orthogonal. The advantage of EH antennas is, that they have much smaller size on frequencies in order of magnitude MHz in comparison with conventional antennas (e.g. half-wave dipole). Their disavantages are their more complicated construction and tuning of the antenna, which must be made again, when the position of antenna is changed. Therefore the EH antenna is not so suitable for mobile application.

The main object of this thesis is the proposal of fitting (setting) hydraulic cylinder into test equipment of ball-joints of company TRW-DAS Dačice a.s. The thesis includes a short review about testing ball-joint of above company and about liquid mechanisms. Also, there are analyzed demands for fitting (setting) hydraulic cylinder into testing equipment. In the main part of this thesis there is described my own constructive proposal with numeric calculations in proper software. In enclosure there are all analytical calculations with productive drawings and an assembly drawing.

The purpose of this dilploma thesis is to evaluate mechanical and structural properties of two types casts of Al-alloy (components of the engine block) which were made by different technologies. Die casting with local squeeze casting and without local squeeze casting. First of them is used in lot manufacture of the current engine block. The aim of the foundry is to change the technology and start to produce new block by the die casting without local squeeze casting. The samples were taken from the both parts (lower and upper part) of the current and the new engine block which are made in foundry of Skoda Auto a.c. in Mladá Boleslav. Sets of mechanical and structural properties were selected, evaluated and tested by statistical programs. It was used fifty casts of the engine blocks for the experiment.

This diploma thesis contains a summary of the general information about the torsion vibration of the crankshaft. The main task is to prepare a flexible model of the crankshaft in the FEM program ANSYS and the subsequent export into the MBS ADAMS / Engine. According to parameters the model of four-cylinder line tractor engine with flexible crankshaft is built. Crank mechanism is analyzed to determine the natural frequencies and natural modes. Finally the results are evaluated and compared with analytical calculations.

The purpose of this thesis is design of in-line a five-cylinder diesel engine arrangement with given main parameters, power train design, balancing centrifugal and inertia moments and calculation of torsion vibrations. The proposed engine must be based on four-cylinder diesel Zetor engine.

Bc. Jaroslav Simcik Construction of hydraulic wood-splitting machine DP, Institute of production machines, systems and robotics, 2010, p. 60, fig. 30, appendices 7, This master ´s thesis is concerned with the wood-processing technology with a focus on the construction of hydraulic wood splitter machine with a force 120 kN.

his diploma work themed: Five-cylinder in-line Diesel engine with balancing unit is dealing with analysis of balancing possible alternatives of arranging crankshaft, analysis of arranging counterweight, concept of balancing shaft, engineering design of crank-shaft, calculation of frequency, computational control of crank-shaft in light of torsional oscillations and proposal of dynamic pendulum damper.