The original test results of abrasive wear resistance of different type of construction polymer materials were presented and discussed in this article. Tests were made on an adapted test stand (surface grinder for form and finish grinding). Test samples were made of different types of polymer board materials including RenShape®, Cibatool® and phenolic cotton laminated plastic laminate (TCF). An original methodology based on a grinding experimental set-up of abrasion wear resistance of polymer construction materials was presented. Equations describing relations between material type and wear resistance were presented and discussed. Micro and macro structures were investigated and used in wear resistance prediction.
The paper represents theoretical and experimental vibration analysis of electronic packages. The research objectives are bearing parts, such as printed circuit boards, walls of the cases and electronic components, in enclosed electronic packages subjected to vibration during their operation. The theoretical model of the oscillation system representing electronic package installed on the support subjected to vibration is described. Vibration transmission from the shaker to the tested electronic package is explained as the complex problem to solve. The experimental measurement verified significant difference in amplitudes of vibrations transmitted inside the package and incident to. The elements of plate bending theory is used for main boards, case walls and other planar rectangular structures considered as equivalent homogeneous plates, in order to estimate their natural frequencies and forms of free cross oscillations and hence to identify their possible resonances with purpose to avoid them in operation. The significant attention was paid to the experimental research of dynamic characteristics, representing results in form of Chladni figures and amplitude frequency responses.
The polymer film, formed on fabric, has a diverse resistance to impact (shear) forces during deformation. An original model of the capillary-porous structure of the fabric, partially filled with polymer, was presented and discussed in this paper. Polymer material fixing relations were developed, taking into account the fabric structure and changes of polymer temperature. Experimental studies were performed on three different materials: artificial leather SK-2, GOST 16119-70 (230 g/m2); genuine beef skin, GOST 939-75 (2.2 g/m3); and fabric denim, GOST 29298-2005 (225 g/m2). The value of mathematical model analysis deviation compared with the experimental value was approximately 12%. The obtained mathematical dependences were the basis for predicting the increase of the dimensional stability of garments by applying hot melt polymer to its surface. It is also possible to design new equipment for its implementation.
The paper represents the mathematical model for diagnostics of supercapacitors. The research objectives are the problem of determining a supercapacitor technical condition during its operation. The general reliability of diagnostics is described as the methodological and instrumental reliabilities of diagnostics. The instrumental diagnostic reliability of supercapacitor includes the probabilities of errors of the first and second kind, α and β respectively. The methodological approach to increasing the reliability of supercapacitor diagnostic has been proposed, in terms of multi-parameter supercapacitor diagnostic by applying nonlinear, frequency dependent mathematical models of supercapacitors that take into account nonlinearity, frequency dispersion of parameters and the effect of transient processes in supercapacitors. The more frequencies, operating voltages and currents are applied in the supercapacitor diagnostics, the more methodological reliability of diagnostics will increase in relation to the methodological reliability of supercapacitor diagnostics when only one frequency, voltage and current are applied.
Knowledge of the technical state and construction of the hydraulic and pneumatic control system of Multimedia Hybrid Mobile Stage HMSM allows you to identify hazards and make a risk assessment. The aspects of the algorithmic process of diagnosing pneumatic and hydraulic control systems presented in the work form the basis for the development and implementation of safe solutions in the process of operation. This article describes the methodology for diagnosing HMSM machine hydraulics and industrial pneumatics systems, detailing the factors determining the correctness of maintaining functional fitness. The considerations developed illustrate the complexity of the diagnostic testing design process for condition assessment.
Excitation and transmission of vibration inside electronic packages are strongly connected with mechanical characteristics of their enclosure, which are in the objective for the current research aimed at developing methods and means to reduce vibration inside the enclosure case. The main idea of the introduced methods is in creating elastic and dissipative mechanical joints between structural elements, which appear to be the links for vibration transmission, inside and outside of the electronic package enclosure. The effectiveness of developed methods is proved by experimental verification and theoretical foundation.