Sharif University of Technology Scientia Iranica 1026-3098 27 3 2020 06 01 A new aspect of transition between line and continuous spectrum and its relation to seismic in influence on structures 1515 1524 20326 10.24200/sci.2018.20326 EN R. Babic Department of Electrical and Computing Engineering, Faculty of Technical Sciences, University of Pristina, Knjaza Milosa Street, No. 7, Kosovska Mitrovica, P.O. Box 38220, Serbia L. Babic Department of Civil Engineering, Faculty of Technical Sciences, University of Pristina, Knjaza Milosa Street, No. 7, Kosovska Mitrovica, P.O. Box 38220, Serbia B. Jaksic Department of Electrical and Computing Engineering, Faculty of Technical Sciences, University of Pristina, Knjaza Milosa Street, No. 7, Kosovska Mitrovica, P.O. Box 38220, Serbia Journal Article 2017 08 04 We considered a new view on transition process from periodic to aperiodic signals, in time and spectral domains, pointing out how the concept of infinity is involved. It contributes to better understanding of the nature of both spectral descriptions, and conditions of their practical use, particularly in unusual cases. There we highlight the invariance in spectrum convergence by introducing some numerical parameters which exactly describe such process. Their behaviour is numerically examined to detail. Also, we considered the opposite transition, from aperiodic to periodic, to clarify the meaning of spectral line. To suggest applicability of our analysis we used an actual seismic signal. By extracting the most prominent waveform part, regarding influence on structures, we formed a periodic signal which line spectrum can clearly show possible resonance with vibrating tones of structures. https://scientiairanica.sharif.edu/article_20326_bdaccd7781386e6e39630d62b39afc40.pdf