EM Cygni is a Z Cam-subtype eclipsing dwarf nova. Its orbital period variations were reported in the past but the results were in conflict to each other while other studies allowed the possibility of no period variation. In this study we report accurate new times of minima of this eclipsing binary and update its O−C diagram. We also estimate the mass transfer rate in EM Cygni system and conclud...

Satellite systems are beginning to incorporate complex autonomous operations, which calls for rigorous reliability assurances. Human operators usually plan satellite maneuvers in detail, but autonomous operation will require software to make decisions using noisy sensor data and problem solutions with numerical inaccuracies. For such systems, formal verification guarantees are particularly attr...

We study the phase diagram of R1−xAxMnO3 (R=La, Pr, Nd, Sm ; A=Ca, Sr, Ba) by taking into account the degeneracy of eg orbitals and the anisotropy of the transfer integral. The electron-electron interaction is treated in the mean field approximation with the optimization of the spin and orbital structures. The global phase diagram is understood in terms of the two interactions, i.e., the super ...

The vibrational frequencies of N-benzoyl glycine in the ground state have been calculated using density functional method (B3LYP) by using 6-311++G(d,p) basis set. Theoretical vibrational spectra have been interpreted by means of potential energy distribution (PEDs) using MOLVIB program. The equilibrium geometry and the thermodynamic functions of the title compound have been performed at HF/6-3...

Hydrogen bond (H-bond) covalency has recently been observed in ice and liquid water, while the penetrating molecular orbitals (MOs) in the H-bond region of most typical water dimer system, (H2O)2, have also been discovered. However, obtaining the quantitative contribution of these MOs to the H-bond interaction is still problematic. In this work, we introduced the orbital-resolved electron densi...

The discovery of supersoft X-ray sources, described as massive white dwarfs burning accreted matter from their (more massive) companions, opens a new channel to type Ia supernovae (SNe Ia). According to conventional binary evolutionary theory, if the mass ratio of the donor to the white dwarf exceeds a critical value, the mass transfer becomes unstable, and a common envelope will be formed. How...

Nonplanar trajectory optimization problem with advanced variable specific impulse magnetoplasma rocket (VASIMR) engine is studied. A newly developed method called Gauss Pseudospectral method is applied to the nonplanar trajectory optimization problem with VASIMR engine. Three representative trajectory optimization problems are solved. The first is an orbit raising problem from LEO to GEO; the s...

A nonlinear nature of the binary ephemeris of Cygnus X-3 indicates either a change in the orbital period or an apsidal motion of the orbit. We have made extended observations of Cygnus X-3 with the Pointed Proportional Counters (PPCs) of the Indian X-ray Astronomy Experiment (IXAE) during 1999 July 3−13 and October 11−14. Using the data from these observations and the archival data from ROSAT, ...

We present results of a binary population synthesis study on the orbital period distribution of wide binary millisecond pulsars forming through four evolutionary channels. In three of the channels, the progenitor of the millisecond pulsar undergoes a common envelope phase prior to the supernova explosion which gives birth to the neutron star. In the fourth channel, the primary avoids the common...