Surface ozone variability at Kislovodsk Observatory

The results of the surface ozone observations at the Observatory 'Kislovodsk', situated in the North Caucasus at the altitude 2070 m a.s.l., are given. The observatory is in the background conditions and the variations of the surface ozone are determined by the natural dynamic and photochemical processes. The mean value of the concentration and its seasonal variations are very near to those obtained at the high-mountain stations in Alps. The daily variations have the features, which remain stable during all warm period of the year (April-October). These features, including the minimum of the surface ozone at noon, are formed by the mountain-valley circulation. The significant variations of the surface ozone are connected with the unstationary lee waves

Discovery of an unusual bright eclipsing binary with the longest known period: TYC 2505-672-1 / MASTER OT J095310.04+335352.8

We report on the MASTER Global Robotic Net discovery of an eclipsing binary, MASTER OT J095310.04+335352.8, previously known as unremarkable star TYC 2505-672-1, which displays extreme orbital parameters. The orbital period P=69.1 yr is more than 2.5 times longer than that of epsilon-Aurigae, which is the previous record holder. The light curve is characterized by an extremely deep total eclipse with a depth of more than 4.5 mag, which is symmetrically shaped and has a total duration of 3.5 yrs. The eclipse is essentially gray. The spectra acquired with the Russian 6 m BTA telescope both at minimum and maximum light mainly correspond to an M0-1III--type red giant, but the spectra taken at the bottom of eclipse show small traces of a sufficiently hot source. The observed properties of this system can be better explained as the red giant eclipsed by a large cloud (the disk) of small particles surrounding the invisible secondary companion.Comment: 8 figures, 9 pages, Astronomy and astrophysics in prin

Photometric observations of the supernova 2009nr

We present the results of our UBVRI CCD photometry for the second brightest supernova of 2009, SN 2009nr, discovered during a sky survey with the telescopes of the MASTER robotic network. Its light and color curves and bolometric light curves have been constructed. The light-curve parameters and the maximum luminosity have been determined. SN 2009nr is shown to be similar in light-curve shape and maximum luminosity to SN 1991T, which is the prototype of the class of supernovae Ia with an enhanced luminosity. SN 2009nr exploded far from the center of the spiral galaxy UGC 8255 and most likely belongs to its old halo population. We hypothesize that this explosion is a consequence of the merger of white dwarfs

Measurements of the total column amount of NO2 at Kislovodsk Observatory in 1979 - 1990

The results of the measurements of the NO2 total content at the 'Kislovodsk' observatory (North Caucasus 2070 m a.s.l.) in 1979-1990 are presented. The measurements were based on the absorption of the direct sunlight in the visible region of the spectrum. The variation of the NO2 content from the morning to the evening and the seasonal and year to year variations are analyzed. The less amplitude of the daily variations of the NO2 total content in comparison with the variations of the stratospheric NO2 content says about the significant insert of the tropospheric and lower stratospheric NO2 in its total content. The year to year variations of NO2 and ozone are in antiphase. Their values depends on the regional features of the atmospheric circulation. The quasibiennial oscillations of the total NO2 content are picked out

SCO and Strategic Development Goals of the Republic of Uzbekistan

This article considers the main problems of further development of cooperation between the SCO member states against the background of the movement of the world community towards multipolarity. The justification of the need to revise traditional approaches to assessing the results of reforms in the post-Soviet territories on the example of Uzbekistan is given. The strategic development goals of the Republic of Uzbekistan that have already been achieved are analyzed, the prospects for strategic cooperation between Uzbekistan and the main SCO member states are outlined. Based on the conducted research the authors conclude that Uzbekistan’s participation in the SCO is a strategic factor in strengthening the economic, energy, military and demographic security of the region

Определение критериев прочности по условиям визуальной контролепригодности ударных повреждений в композитных авиационных конструкциях

One of the principal criteria of aircraft composite design strength on the conditions of damage tolerance is the minimum defect size of accidental impact damage that is sure to be located during regular maintenance checks. Construction strength with similar (BVID – Barely Visible Impact Damage) and smaller damages must be ensured under design load. The analysis of operational factors affecting the criterion value is conducted in the paper. The effects of personnel qualification, surface color, level of contamination, distance to the object as well as defect size variations during the time due to relaxation of inner strains in the damaged construction were studied.Research was carried out using 90 carbon fiber three stinger panels of different color and contamination levels which were subject to impact damages by a 25 mm spherical striker. Totally 80 blows were struck when applying energy within the range of 3–107 J. In the visual damage detectability test under different conditions 42 experts were participated including 25 airlines inspectors. For the statistical analysis of empirical data and determination of dependence for the damage detection probability on its size, the Weibull function was utilized. Determination of BVID size using "90/95" criterion was performed by means of the bootstrap method (95% of inspectors must detect not less than 90% of defects with the size not smaller than BVID). The results obtained in this study enabled to access the degree of various operational factors impact on reliability of damage detectability during the visual inspection and determine BVID values depending on the combination of the given factors. In particular, it was demonstrated that from all the viewing distances the defects in polymer composite materials are more detectable on the blue surface than on the gray and red ones. Conducted research demonstrated a significant effect of relaxation (the reduction effect of the surface defect sizes in the composite panel affected by different factors during time span) on the probability of defect detectability during operation. Also water saturation of the construction under excessive temperatures has the critical compared with other factors impact on relaxation of damages in polymer composite materials. The obtained results accord with the data in foreign publications making them more supplement and specific. On the basis of conducted research the entire range of recommendations for aircraft designers and operators utilizing composite constructions is formulated. Одним из основных критериев прочности композитной авиационной конструкции по условиям допускаемых повреждений является минимальный размер дефекта от случайного ударного повреждения, который гарантированно обнаруживается при стандартных формах технического обслуживания самолета. Прочность конструкции, имеющей такие (называемые BVID – Barely Visible Impact Damage) и меньшие повреждения должна быть обеспечена при расчетной нагрузке. В работе выполнен анализ эксплуатационных факторов, влияющих на величину этого критерия. Исследовано влияние квалификации персонала, цвета поверхности, уровня загрязненности, расстояния до объекта, а также явления изменения размера дефекта во времени вследствие релаксации внутренних напряжений в поврежденной конструкции. Исследования проводились с использованием 90 углепластиковых трехстрингерных панелей различного цвета и степени чистоты, на которые 25-миллиметровым сферическим бойком были нанесены ударные повреждения. Всего было нанесено 80 ударов с энергией в диапазоне 3–107 Дж. В эксперименте по визуальной обнаруживаемости повреждений в различных условиях участвовали 42 специалиста, в том числе 25 сотрудников авиакомпаний. При статистической обработке экспериментальных данных и определении зависимости вероятности обнаружения повреждения от его размера использовалась функция Вейбулла. Оценка размера BVID по критерию «90/95» (95 % проверяющих должны обнаружить не менее 90 % дефектов с размером не меньше BVID) выполнялась с помощью технологии бутстреп-моделирования. Результаты проведенного исследования позволили оценить степень влияния различных эксплуатационных факторов на надежность выявления повреждений при визуальном эксплуатационном контроле и определить значения BVID в зависимости от комбинации этих факторов. В частности, показано, что на синей поверхности повреждения в ПКМ видны лучше, чем на красной или серой, при любом расстоянии до объекта. Выполненные исследования продемонстрировали существенное влияние релаксации (эффекта уменьшения со временем под воздействием различных факторов размеров поверхностного дефекта в композитной панели) на возможность выявления дефекта в эксплуатации. При этом критическое по сравнению с другими факторами влияние на релаксацию повреждений в ПКМ оказывает режим влагонасыщения конструкции при повышенных температурах. Полученные результаты хорошо согласуются с опубликованными в иностранных источниках данными, существенно их дополняя и конкретизируя. На основе проведенных исследований сформулирован ряд рекомендаций для разработчиков и эксплуатантов авиационных конструкций из композиционных материалов

Prompt, early, and afterglow optical observations of five gamma-ray bursts (GRBs 100901A, 100902A, 100905A, 100906A, and 101020A)

We present results of the prompt, early, and afterglow optical observations of five gamma-ray bursts, GRBs 100901A, 100902A, 100905A, 100906A, and 101020A, made with the Mobile Astronomical System of TElescope-Robots in Russia (MASTER-II net), the 1.5-m telescope of Sierra-Nevada Observatory, and the 2.56-m Nordic Optical Telescope. For two sources, GRB 100901A and GRB 100906A, we detected optical counterparts and obtained light curves starting before cessation of gamma-ray emission, at 113 s and 48 s after the trigger, respectively. Observations of GRB 100906A were conducted with two polarizing filters. Observations of the other three bursts gave the upper limits on the optical flux; their properties are briefly discussed. More detailed analysis of GRB 100901A and GRB 100906A supplemented by Swift data provides the following results and indicates different origins of the prompt optical radiation in the two bursts. The light curves patterns and spectral distributions suggest a common production site of the prompt optical and high-energy emission in GRB 100901A. Results of spectral fits for GRB 100901A in the range from the optical to X-rays favor power-law energy distributions with similar values of the optical extinction in the host galaxy. GRB 100906A produced a smoothly peaking optical light curve suggesting that the prompt optical radiation in this GRB originated in a front shock. This is supported by a spectral analysis. We have found that the Amati and Ghirlanda relations are satisfied for GRB 100906A. An upper limit on the value of the optical extinction on the host of GRB 100906A is obtained.Comment: 18 pages, 14 figures, 14 tables, 5 machine readable tables; accepted for publication in MNRA