Marek Szmechta

  • Citations Per Year
Learn More
In paper a system for road surface defects detection is presented. Traditional approaches use human eye or specialized hardware to evaluate quality of the road. There are also systems known basing on mobile sensors network. Our approach bases on collecting GPS and accelerometer data from mobile phones of large number of individual, anonymous car drivers.(More)
This paper presents some observations of data packet delaying in a real productive industrial telemetry system. It introduces the statistical analysis of measured Round Trip Time (RTT) values of used Internet Control Management Protocol (ICMP) and User Datagram Protocol (UDP) packets usually used in such applications. Scheduled ICMP delay measurements are(More)
Acoustic emission measurement results of acoustically induced cavitation bubbles in insulating oil are presented in this paper. Spectral analysis of acquired by a broadband transducer acoustic emission signals is proposed as a diagnostic tool for estimation of aging properties of mineral insulating oils. The article describes the main parts of the designed(More)
The paper presents some spectral analysis results of acoustic emission observed during ultrasound driven round bottomed flask with fresh insulating oil inside. At suitable value of signal amplitude and frequency many of cavitation bubbles were observed. Collapsing bubbles were responsible for broadband noise included in acoustic emission signal spectra. To(More)
The paper presents some observations of ultrasound induced cavitation phenomenon in mineral insulating oil. The acoustic cavitation phenomenon was generated at different signal frequencies and rms voltage value supplied to round piezoelectric transducers. Used transducers have created a high energy acoustic field in prepared insulating oil samples. The(More)
The paper presents the behavior of ultrasound induced cavitation voids and bubbles in mineral insulating oils with different aging properties. At suitable values of signal amplitude and frequency many of cavitation bubbles were observed. Collapsing bubbles were responsible for broadband noise included in acoustic emission signal spectra. To represent the(More)
In paper the influence of thermal oxidation on nano-modified transformer oil is analyzed. The probes of mineral transformer were doped with different content of C<inf>60</inf> fullerenes from 0 mg/l to 512 mg/l. One set of probes were then aged for 64 hours in the temperature of 110&#x00B0;C with the presence of copper inhibitor. Oil parameters such us:(More)
  • 1