TYC 1031 01262 1: The First Known Galactic Eclipsing Binary with a Type II Cepheid Component

We present the discovery and CCD observations of the first eclipsing binary with a Type II Cepheid component in our Galaxy. The pulsation and orbital periods are found to be 4.1523 and 51.38 days, respectively, i.e. this variable is a system with the shortest orbital period among known Cepheid binaries. Pulsations dominate the brightness variations. The eclipses are assumed to be partial. The EB-subtype eclipsing light curve permits to believe that the binary's components are non-spherical.Comment: 3 pages, 3 figures, accepted to MNRAS Letter

THIACALIX[4]ARENES DERIVATIVES: FROM SELF-ASSEMBY TO FUNCTIONAL MATERIALS

This work was supported by the by Russian Science Foundation, project # 19-13-00095

Cross-relaxation and phonon bottleneck effects on magnetization dynamics in LiYF4:Ho3+

Frequency and dc magnetic field dependences of dynamic susceptibility in diluted paramagnets LiYF$_4$:Ho$^{3+}$ have been measured at liquid helium temperatures in the ac and dc magnetic fields parallel to the symmetry axis of a tetragonal crystal lattice. Experimental data are analyzed in the framework of microscopic theory of relaxation rates in the manifold of 24 electron-nuclear sublevels of the lowest non-Kramers doublet and the first excited singlet in the Ho$^{3+}$ ground multiplet $^5I_8$ split by the crystal field of S$_4$ symmetry. The one-phonon transition probabilities were computed using electron-phonon coupling constants calculated in the framework of exchange charge model and were checked by optical piezospectroscopic measurements. The specific features observed in field dependences of the in- and out-of-phase susceptibilities (humps and dips, respectively) at the crossings (anti-crossings) of the electron-nuclear sublevels are well reproduced by simulations when the phonon bottleneck effect and the cross-spin relaxation are taken into account

LINEAR PROGRAMMING AND DYNAMICS

In a Hilbert space we consider the linear boundary value problem of optimal control based on the linear dynamics and the terminal linear programming problem at the right end of the time interval. There is provided a saddle-point method to solve it. Convergence of the method is proved

Компьютерное моделирование ветровых нагрузок на высотные здания

The paper presents the results of numerical simulation of wind pressure on high rise buildings being under construction and planned in Yekaterinburg city (Russia). Simulation is performed in the program ANSYS. The simulated building is placed in a domain that is the numerical analogue of wind tunnel. Domain sizes are chosen in such a way that simulated buildings do not affect the flow of air on its boundaries. Shear stress transport (SST) turbulence model is used. In order to validate the numerical model the paper presents the results of experimental study and numerical simulation of external air flow around the cylindrical body with the diameter of 8 mm, placed on the way of free submerged jet of air. The cylinder which has simple geometry form was used due to the need to achieve the generality of the outcomes. A comparison of the results of calculation of wind pressure with the experimental data blasting building models in wind tunnels is done.В статье представлены результаты численного моделирования задачи определения ветровых давлений на строящиеся или проектируемые в г. Екатеринбурге (Россия) высотные здания. Задача решается в пакете ANSYS. Моделируемое здание и его окружение помещаются в домен, который является численным аналогом ветровой трубы. Размеры домена назначаются таким образом, чтобы объекты, входящие в домен, не влияли на движение воздуха у внешних границ домена. Для расчета используется модель SST. Для проверки правильности численной модели приводится сравнение результатов расчета с экспериментальными данными обдувки цилиндра диаметром 8 мм. Такая модель простой формы выбрана для удобства сравнения. Приведено сравнение численных результатов расчета давлений ветра на высотные здания с результатами обдувки в ветровых трубах