the noise profile. In order to locate the various sources of noise of the hermetic rolling position type compressor for room air conditioners, we experimentally analyzed the compressor noise and found that a main cause of the·noise was the acoustically amplified pressure pulsation in various parts of the compressor. Moreover, with reference to results of this noise source analysis, several proc...

We present the analysis of photometric and spectroscopic data of two classical Cepheids, FN Aquilae and V1344 Aquilae. Based on the joint treatment of the new and earlier radial velocity data, both Galactic Cepheids have been found to be a member in a spectroscopic binary system. To match the phases of the earlier radial velocity data correctly with the new ones, we also determined the temporal...

OUR investigations assumed first that the difference of pressure between the arterial and venous parts of the capillary system acts as circulatory motor, further, that spontaneous venous pulsation of the fundus of the eye is a sign of a pressure prevailing within the central retinal vein lower than the intra-ocular tension. One hundred cases were examined: fifty of them showing spontaneous puls...

Context. Hot DQ white dwarfs constitute a new class of white dwarf stars, uncovered recently within the framework of the SDSS project. There exist nine of them, out of a total of several thousands white dwarfs spectroscopically identified. Recently, three hot DQ white dwarfs have been reported to exhibit photometric variability with periods compatible with pulsation g-modes. Aims. Here, we pres...

We report recent XMM-Newton investigations of PSR J1836+5925, the “next Geminga,” which determined an X-ray pulsation of ∼173.3 ms. Its X-ray periodicity is consistent with the γ -ray ephemeris at the same epoch. The X-ray folded light curve has a sinusoidal structure that is different from the double-peaked γ -ray pulse profile. We have also analyzed the X-ray phase-averaged spectra which show...

We introduce a simple method for determining pulsation velocities of Cepheid variables; namely, the matching of observed spectral line profiles in both shape and absolute position with model profiles. This approach avoids the ambiguous meaning of radial velocity for asymmetric lines, and it avoids the awkward projection factor (the “p” factor) used to expand radial velocities to pulsation veloc...

We show that the light of a commercially available Er : Yb :Cr :phosphate glass microchip laser end-pumped at 977 nm by an InGaAs laser diode can be switched between two linear polarization eigenstates when it is submitted to a polarized optical feedback. The flip occurs when the feedback phase is scanned by the external cavity length. In our experiments the laser diode light is confined to a f...

Optical bistability and dynamic instability are experimentally observed and studied in a system consisting of three-level L-type rubidium atoms in an optical ring cavity. The bistable behavior and self-pulsing frequency are experimentally manipulated by changing the controlling and cavity field parameters ~power and frequency!. These nonlinear effects are influenced by the enhanced Kerr nonline...

G. Kozyreff, T. Erneux, M. Haelterman, and P. Kockaert Optique Nonlinéaire Théorique, Université Libre de Bruxelles, Code Postal 231, Campus Plaine, B-1050 Bruxelles, Belgium ICFO—Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain Service d’Optique et Acoustique, Université Libre de Bruxelles, Code Postal 194/5, avenue F.D. Roosevelt 50, B-1050...