Active magnetic bearings require some form of control, based on feedback of the position of the suspended object, to overcome open–loop instability and to achieve targeted system performance by modifying the bearing dynamics. In many applications of magnetic bearings, a need to eliminate discrete position sensors may arise either from economic or reliability considerations. Magnetic bearings wh...

The Modified Winding Function Theory (MWFTh), regarded as a very powerful and general theory, has been extensively used for the last 15 years. This paper performs an in-depth review of the mathematical and physical framework on which the MWFTh is based, showing that it is indeed very well suited to analyse machines with small air gaps of arbitrary shape. However, contrary to what is usually sta...

The characteristics of acoustic wave transmitting in a metamaterial-type seawater piping system are studied. The metamaterial pipe, which consists of a uniform pipe with air-water chamber Helmholtz resonators (HRs) mounted periodically along its axial direction, could generate a wide band gap in the low-frequency range, rendering the propagation of low-frequency acoustic waves in the piping sys...

For a nonsmooth multiobjective mathematical programming problem governed by infinitely many constraints‎, ‎we define a new gap function that generalizes the definitions of this concept in other articles‎. ‎Then‎, ‎we characterize the efficient‎, ‎weakly efficient‎, ‎and properly efficient solutions of the problem utilizing this new gap function‎. ‎Our results are based on $(Phi,rho)-$invexity‎,...

Raman spectra of ordered carbon nanomaterials are quite sensitive to surface perturbations, including trace residues, structural defects and residual stress. This is demonstrated by a series of experiments with carbon nanotubes and graphene. Their spectra change due to subtle changes in preparation and attachment to the substrate and to each other. Differences are most clearly seen by forming a...

OBJECTIVES This study aims to report early postoperative complications and hearing results in patients with chronic otitis media undergoing endoscopic transcanal tympanoplasty. PATIENTS AND METHODS Twenty-four patients (6 males, 18 females; mean age 25.9 years; range 9 to 46 years) who were operated with endoscopic transcanal tympanoplasty in the Department of Otorhinolaryngology, Faculty of ...