An approximate strategy for studying the evolution of binary systems of extended objects is introduced. The stars are assumed to be polytropic ellipsoids. The surfaces of constant density maintain their ellipsoidal shape during the time evolution. The equations of hydrodynamics then reduce to a system of ordinary differential equations for the internal velocities, the principal axes of the star...

typically, two configurations are used for energy harvesting, with different advantages: piezoelastic and piezomagnetoelastic. best performance of piezoelastic configuration is limited to its narrow bandwidth around the resonance frequency. if the excitation frequency slightly deviates from the resonance frequency, the power-out is severely reduced. to overcome this, the piezomagnetoelastic has...

Islam spread rapidly after its founding, encompassing much of North Africa, the Middle East, and Southeast Asia. The art of this vast region draws its distinctive character both from Islam itself and from the diverse cultural traditions of the world’s Muslims. Because Islam discouraged the use of figurative images, particularly in religious contexts- unlike Christian art- Islamic artists develo...

The discovery of transiting circumbinary planets by the Kepler mission suggests that planets can form efficiently around binary stars. None of the stellar binaries currently known to host planets has a period shorter than 7 d, despite the large number of eclipsing binaries found in the Kepler target list with periods shorter than a few days. These compact binaries are believed to have evolved f...

3D Continuum radiative transfer in complex dust configurations around young stellar objects and active nuclei II. 3D Structure of the dense molecular cloud core ρ Oph D Abstract. Constraints on the density and thermal 3D structure of the dense molecular cloud core ρ Oph D are derived from a detailed 3D radiative transfer modeling. Two ISOCAM images at 7 and 15 µm are fitted simultaneously by re...

Binary black holes on quasicircular orbits with spins aligned with their orbital angular momentum have been test beds for analytic and numerical relativity for decades, not least because symmetry ensures that such configurations are equilibrium solutions to the spin-precession equations. In this work, we show that these solutions can be unstable when the spin of the higher-mass black hole is al...

Context. The ages and metallicities of the dominating stellar populations of galaxies without current star formation (e.g., early type galaxies) are usually estimated by comparing the observed absorption line indices or colors to predictions of some simple stellar population models. However, some studies show that there is recent star formation in galaxies, including early type galaxies. This s...

A planet's surface conditions can significantly impact its climate and habitability. In this study, we use the 3D general circulation model ExoPlaSim to systematically vary dayside land cover on a synchronously rotating, temperate rocky planet under two extreme opposite continent configurations, in which either all of or ocean is centred at substellar point. We identify water vapour sea ice as ...

In this work, we study the effects of temperature on magnetic white dwarfs. We model their interior as a nuclei lattice surrounded by relativistic free Fermi gas electrons, accounting for from temperature, Landau levels and anomalous moment. find that, at low densities (corresponding to outer regions star), both field play an important role in calculation microscopic thermodynamical quantities....