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Modal methods are classified among the methods of condition monitoring as a global method. Their main characteristic is that they allow only the determination of the status of airworthiness design without the ability to accurately locate the fault. This paper present use of experimental modal analysis to assess changes in the stiffness of the simple component and verified possibilities of this method to accurately locate the fault. [ABSTRACT FROM AUTHOR]

Concerns relating to the accurate representation real model with virtual model created in CAD programs could have a significant effect on the results obtained from the analyzes of dynamic on these models. This article presents the results related the performed dynamic analysis, based on the theoretical modal analysis implemented in Autodesk Inventor and experimental modal analysis conducted on the real object. [ABSTRACT FROM AUTHOR]

Dockside cranes must meet the relevant strength requirements that provide usefulness and not endanger the safety of their use. The vibration effect on structural safety hazard results from the impact of horizontal forces caused by the transport of goods for loading and transverse forces caused by wind, which can be dangerous for correct functioning. In addition, there are often serious effects of climate-related impacts of the environment, material fatigue, which actuates the degradation state of the object. Dynamic loads may therefor cause random effects that devastate the structures or lead to their catastrophic destruction. Recognizing the need to improve the testing methods of crane structures in order to assess their condition and assess their safety factors - this paper attempts to develop a methodology for testing the degradation of the selected portion of a construction crane - using experimental modal analysis, realized in simulation tests in the Inventor environment as well as at test stand research. [ABSTRACT FROM AUTHOR]

The paper presents issues related to the diagnosis of rotating machinery. It focuses on the diagnosis of the state of these machines through the use of vibroacoustics using databases. In every stage of life machines are useful methods of diagnosis vibroacoustic. It also presents the possibility of rotating machine monitoring system VIBstand. [ABSTRACT FROM AUTHOR]

Steel structures are subject to large dynamic loads clearly reflected by generated vibration processes. The vibrations may affect state of serviceability of structures by lowering comfort of persons working there as well as possible reaching the level hazardous to safety of the structures. The effect of vibrations to structure is mainly manifested by additional stresses in a given cross-section, which are summed up with those resulting from static loads. The dynamic loads may cause damaging effects in buildings of various structural types or even lead to their destruction. Judging the necessity of improving the quality assessment methods of building structures for purposes of estimation of their state as well as safety factors for brick structures, the author of this work undertook an attempt to investigate destruction process of selected object by using the method of experimental modal analysis. [ABSTRACT FROM AUTHOR]

The possibilities of vibroacoustics methods applying in the audits of the chosen units of the of the combustion engine timing rear units were introduced in this paper. The possibility of the modal analysis methods implementation in the process of modelling and diagnostic audits were presented in the peculiarity. The example of the various modal analysis methods use in experimental audits for the timing gear camshaft of the combustion engine was introduced in the investigative piece of the work. [ABSTRACT FROM AUTHOR]

The paper presents issues related with vehicles turbochargers exploitation problems and damage. The article also presents aspects concerning the causes and effects of the most frequent recharging devices defects. Were described operating parameters, as well as the proper operation of the charging system. The main part of this work shows the typical turbocharger components damages. The next part of article present methods of verification recharging devices, so we could lowering the probability of damage, which has a direct influence on the turbochargers reliability. [ABSTRACT FROM AUTHOR]

In this paper we explained the notion of safety and made its division. Besides lists and describes the basic types of tasks and sta-be laid to systems and systems for improving the safety of traveling by car. Were discussed directions of development of safety systems. Moreover, the scope of work includes the study of the damage safety features, which are described causes damage to some systems and methods for testing the characteristics of the elements that allows to verify the effectiveness of the entire system. The main part of the work includes representation sposbu procedure when diagnosing elements on the example of the SRS Airbag Passenger car-go, the results of the research, their analysis and conclusions drawn from the experiments performed. [ABSTRACT FROM AUTHOR]

Building constructions and their elements must meet requirements related to stability and strength. These are the conditions that determine the safety of the structure during both construction and operation. Safety assessment is based on diagnostic tests, aimed at checking the quality of the erected objects or locating damage to structural elements that arise during operation. This work focuses on experimental SISO modal analysis of ceramic masonry elements. An experiment was carried out on twenty samples of solid brick (good, and intentionally damaged). From this, it was possible to determine the variability of the obtained measurement results of the vibration characteristics of the masonry element, and, thus, to assess the value of the method used in the given research problem. The aim of this study was to test the effectiveness of assessing the degradation of the tested brick elements based on stabilization diagrams. The research confirmed the usefulness of experimental modal analysis in identifying damage to masonry elements, and it has been implemented in selected brickyards in Poland. [ABSTRACT FROM AUTHOR]

Production cost reduction and constraints on natural resources cause the use of waste materials as substitutes of traditional raw materials to become increasingly important. The dynamic development of sewerage systems and sewage treatment plants leads to increases in the produced sewage sludge. According to the Waste Law, municipal sewage sludge can be used if it is properly stabilized. This process results in significant quantities of fly ash that must be utilized. This paper presents investigation results of partial cement replacement influence by the fly ash from sewage sludge on concrete parameters. The results confirm the possibility of fly ash waste applications as a cement substitute in concrete manufacturing. In the later parts of the publication, a pilot study was conducted using the modal analysis methodology and aimed at checking the hypothesis of whether vibration methods can be used in the assessment of the amount of the admixture used in concrete and the effect it has on concrete properties. This is the first time that vibration tests have been used to determine the diversity of the concrete mix composition and to distinguish the percentage of ash added. There are no studies using modal analysis to distinguish the composition of a concrete mix in the scientific literature. The article shows that the vibration test results show the differentiation of concrete composition and can be further improved as a method for determining the composition of mixtures and for distinguishing their mechanical properties. These are only pilot studies, which, in order to develop the target cognitive inference, should be performed in the future on a significantly enlarged number of the studied samples. [ABSTRACT FROM AUTHOR]

The engines thermal balance is understood as heat chapter, emitted on individual component during combustion process (divided into effective energy and radiation energy losses). This balance lets us to estimate of heat usefulness as well as heat losses and indicate the ways of losses reduction by utilization of exhaust gases. The thermal balance also indicate the ways of engine coefficient improvements as well as cooling system development and improvement. The thermal balance is draw up during experimental investigations for chosen different conditions of engine work. We could find in literature two types of combustion engine thermal balances: internal and external. In this paper were introduced theoretical issue connected with thermal balance indication and the differences between this types of balance were talk over. [ABSTRACT FROM AUTHOR]