**8. References**

Bishop, C. M. (2006). *Pattern Recognition and Machine Learning*, Vol. 4 of *Information science and statistics*, Springer.

<sup>5</sup> http://www.seisvol.kishou.go.jp/eq/shindo\_db/shindo\_index.html

<sup>6</sup> http://neic.usgs.gov/neis/qed/

**16** 

*Poland* 

**Fibre-Optic Sagnac Interferometer as** 

Leszek R. Jaroszewicz1, Zbigniew Krajewski1 and Krzysztof P. Teisseyre2

The possibility of a direct monitoring of rotational events has an important role in the seismological sciences as well as in the applied physics regarding large engineering

According to the first aspect, a possibility of existence of the rotational phenomena in the seismic field has been discussed from the beginning of the earthquakes investigations. The interest in these phenomena has been stimulated by strange, rotary and even screw-like deformations that occur after earthquakes, often appearing on parts of tombs and monuments (Ferrari, 2006; Kozák 2006). The classical textbooks on seismology deny the possibility that the rotational phenomena, especially in form of seismic rotational waves – SRW, could pass through a rock, so the earthquake rotational phenomena were explained by an interaction of standard seismic waves with a compound structure of objects they penetrate, which, in fact, might be the case (Teisseyre & Kozak, 2003). Nevertheless, it was theoretically proved that even the SRW could propagate through grained rocks; later on, this possibility was extended on rocks with microstructure or defects (Eringen, 1999; Teisseyre & Boratyński, 2002) or even without any internal structure (Teisseyre, 2005; Teisseyre et al., 2005; Teisseyre & Górski, 2009), due to the asymmetric stresses in the medium. It should be noticed that the SRW were for the first time effectively recorded in Poland in 1976 (Droste & Teisseyre, 1976). From this time, waves of this type have been studied in a few centers over the world. Taking into consideration large engineering structures, the rotational events monitoring is connected to the torsional effects in structures as well as to the interstory drift. Since the application of new materials and technologies for building constructions, they have irregular structures in-plane which causes difficulties in designing of the horizontal rotations of these structures especially during earthquakes (Schreiber et al., 2009). Recently in the above areas, the first monographs have been published (Teisseyre et al., 2006, 2008; Lee et al., 2009), covering the theoretical aspects of the rotation motion generation and propagation, as well as the

A further experimental verification of the existing rotational phenomena in seismic events needs a new approach to the construction of the measuring devices, because the

**1. Introduction** 

examples of the field experiments.

structures.

**Seismograph for Direct Monitoring** 

**of Rotational Events** 

*1Military University of Technology* 

*2Institute of Geophysics Polish Academy of Sciences* 

Cheng, H., Tan, P.-N., Potter, C. & Klooster, S. (2008). Data mining for visual exploration and detection of ecosystem disturbances, *Proceedings of the 16th ACM SIGSPATIAL international conference on Advances in geographic information systems - GIS '08* p. 1.

Chih-Chung, C. & Chih-Jen, L. (2011). LIBSVM-a Library for Support Vector Machine. URL: *http://www.csie.ntu.edu.tw/ cjlin/libsvm/*

	- URL: *http://earthquake.usgs.gov/earthquakes/dyfi/*
	- URL: *http://svmlight.joachims.org/*

URL: *http://www.chokkan.org/software/classias/index.html.en*

