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EN
The work presents the research and analysis concerning general low frequency vibration and its effect on energy balance of a human organism (a comparison with a control group). The research was conducted in two phases: a group exposed to vibration and a control group. An exposed group (28 participants) took part in 19 training sessions, each lasting 20 min, of low frequency vibration (around 3.2 Hz in standing position) applied to each participant at fixed time of the day. Before and after the session, the thermographic images were taken and deep temperature was taken too. The control group (33 participants) also took part in 19 everyday 20-min sessions with no vibrations and only measurements conducted. The results were analysed concerning statistics using Statistica. For the sake of the analysis the significance level was p = 0.05, the parametric T - test, and the non-parametric Kołmogorow-Smirnow tests were used for two groups of independent variables. Having conducted the research and analysis, one can state that 20-min exposure to low frequency vibration results in significant positive changes in chosen parameters.
EN
Unfocused/weakly focused pressure pulses (UPP) are generated by an "air-gun" like mechanism, with a projectile accelerated by pressurized air and impinging on a metal applicator. They were introduced in 1998 for the treatment of orthopedic soft tissue pain. The patient side of the applicator (a circular piston of 6-30 mm diameter) releases single pressure pulses of 2-10 MPa and 4-5 μs duration. Up today, there is no standard for the measurement of UPP sources (UPPS), so data are often reported on the basis of the focused lithotripter standard IEC61846. The purpose of this research is to establish methods to reliably measure UPPS acoustic parameters and establish a parameter set based on definitions from focused lithotripsy sources as applicable. Therefore, acoustic characteristics and wave fields of the pressure pulses of UPPS from different manufacturers were measured in a water bath and in a dry test bench. It was demonstrated by comparison with optical hydrophones that piezoelectric hydrophones are appropriate for the measurements of UPP. For on-axis measurements at a fixed distance, measurements in the dry test bench can replace water-bath measurements. Additionally, the dry test bench allows for reliable results at pulse rates >1 Hz.
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