Ma L., Yin Zh. «Possible solar modulation of pacific decadal oscillation» Астрономический вестник, 51, № 5, с. 450 (2017)

The Pacific Decadal Oscillation (PDO) is an El Nino-like pattern of Pacific climate variability, oscillating between its warm and cool phase about every 20–30 years as defined by oceanic temperature anomalies in the northeast and tropical Pacific Ocean. In this work, the authors investigate the possible connection between the PDO and solar activity by means of wavelet technique. The study shows obvious fluctuation characteristics in the PDO series. The modulation action from solar activity plays an important role in the oscillation of the Pacific, and there is a possible association existing in the PDO and solar activity on decade time scales.

Malytskyy D., Pavlova A., Grytsai O., Astashkina O., Obidina O.O., Makhnitskyy M.P., Kozlovskyy E. «Models of seismic sources» Геоинформатика (Геоінформатика, укр.), № 3, с. 14-23 (2016)

Purpose. The paper proposes new methods to determine the parameters of the point and the extended sources of earthquakes. Design/methodology/approach. The source mechanism of an earthquake is determined by a graphic method from polarities of the P-waves first arrival, emergence angles (or angles of incidence) of the first P-waves at the stations, and station azimuths. The accuracy of the nodal planes on the focal sphere in the graphic method is significantly improved by accounting for important additional information contained in fuzzy P-wave arrivals and the logarithm of S- to P-wave amplitude ratio. Emergence angles of P-waves at the stations, and station azimuths are calculated using a software package for each of the events. In case of an insufficient number of stations, we propose an earthquake mechanism to determine by inversion only waveforms of direct P-waves at the stations. Findings. The inversion method consists in determining seismic moment tensor at a station and subsequently translating the solution into the event’s hypocenter. The extended source is modeled by solving the inverse problem as a set of point sources and their parameters. The problem of the earthquake source is therefore solved in two steps: 1) identification of source mechanism; 2) determination of slip, rise time, and rupture time for each of the elementary point sources. Correctness of the problem is improved by adding a constraint on the horizontal component of wave number. Practical value /implications. Using the data from the project SIV, we present practical application of the methods to determine both the point and the extended sources.

Malytskyy D., Pavlova A., Grytsai O., Astashkina O., Obidina O.O., Makhnitskyy M.P., Kozlovskyy E. «Models of seismic sources» Геоинформатика (Геоінформатика, укр.), № 3, с. 14-23 (2016)

Purpose. The paper proposes new methods to determine the parameters of the point and the extended sources of earthquakes. Design/methodology/approach. The source mechanism of an earthquake is determined by a graphic method from polarities of the P-waves first arrival, emergence angles (or angles of incidence) of the first P-waves at the stations, and station azimuths. The accuracy of the nodal planes on the focal sphere in the graphic method is significantly improved by accounting for important additional information contained in fuzzy P-wave arrivals and the logarithm of S- to P-wave amplitude ratio. Emergence angles of P-waves at the stations, and station azimuths are calculated using a software package for each of the events. In case of an insufficient number of stations, we propose an earthquake mechanism to determine by inversion only waveforms of direct P-waves at the stations. Findings. The inversion method consists in determining seismic moment tensor at a station and subsequently translating the solution into the event’s hypocenter. The extended source is modeled by solving the inverse problem as a set of point sources and their parameters. The problem of the earthquake source is therefore solved in two steps: 1) identification of source mechanism; 2) determination of slip, rise time, and rupture time for each of the elementary point sources. Correctness of the problem is improved by adding a constraint on the horizontal component of wave number. Practical value /implications. Using the data from the project SIV, we present practical application of the methods to determine both the point and the extended sources.

Фатеев В.О., Конопацкая И.И., Пятаков П.А., Mironov M.A. «Измерение производительности акустического фонтана» Ученые записки физического факультета МГУ, № 5, http://uzmu.phys.msu.ru/toc/2017/5 (2017)

Измерена производительность (объемная скорость) акустического фонтана и показано, что производительность пропорциональна акустической мощности. Определен коэффициент пропорциональности.

Конопацкая И.И., Mironov M.A., Пятаков П.А. «Ультразвуковой контроль состояния волноводной конструкции» Ученые записки физического факультета МГУ, № 5, http://uzmu.phys.msu.ru/toc/2017/5 (2017)

Представлены результаты экспериментальных исследований возможности применения корреляционного метода для регистрации изменений состояния волновода стержневого типа под действием локального сжатия и нагрева. Показана возможность использования этого метода для контроля качества болтового соединения компонентов твердотельной волноводной конструкции.