1. Why understand spectral analysis * 2. Relationships between variables * 3. Time varying signals * 4. Describing signals in terms of frequency * 5. Frequency representation of random signals * 6. Identifying systems relationships from measurements * 7. Some typical applications * 8. Wave directionality monitoring * 9. Motions of moored structures in a seaway * 10. Experimental measurment and time series acquisition * 11. Experimental evaluation of wide band active vibration * 12. Hull roughness and ship resistance * References * Appendices * Index.