This paper discusses the control relevant parametric identification of a servo system present in a Compact Disc player. In this application an approximate closed loop identification problem is solved in order to come up with a linear multivariable discrete time model, suitable for control design. This identification problem is handled by a recently introduced two stage method. It yields an expl...

We present three-dimensional hydrodynamic simulations of the evolution of selfgravitating, thick accretion discs around hyperaccreting stellar-mass black holes. The black hole-torus systems are considered to be remnants of compact object mergers, in which case the disc is not fed by an external mass reservoir and the accretion is non-stationary. Our models take into account viscous dissipation,...

The periodic disturbances caused by the inherent eccentricity and unbalancing in compact disc systems is one of the prominent radial-tracking problems in high-speed and high-density optical storage systems. To compensate these periodic disturbances, an adaptive feedforward compensation technique is presented and investigated with the aim to have cost-effective optical disc drive manufacturing. ...

A low-cost, direct fabrication technique with a micrometer range resolution has been implemented for rapid prototyping of optical masks for photolithography and structured light and diffraction optics applications. Using a setup based on the optical unit of a compact disc-digital versatile disc burner, a low-energy infrared laser beam was focused on a thin polymeric layer with embedded absorbin...