New class I methanol masers

We review properties of all known collisionally pumped (class I) methanol maser series based on observations with the Australia Telescope Compact Array (ATCA) and the Mopra radio telescope. Masers at 36, 84, 44 and 95 GHz are most widespread, while 9.9, 25, 23.4 and 104 GHz masers are much rarer, tracing the most energetic shocks. A survey of many southern masers at 36 and 44 GHz suggests that these two transitions are highly complementary. The 23.4 GHz maser is a new type of rare class I methanol maser, detected only in two high-mass star-forming regions, G357.97-0.16 and G343.12-0.06, and showing a behaviour similar to 9.9, 25 and 104 GHz masers. Interferometric positions suggest that shocks responsible for class I masers could arise from a range of phenomena, not merely an outflow scenario. For example, some masers might be caused by interaction of an expanding HII region with its surrounding molecular cloud. This has implications for evolutionary sequences incorporating class I methanol masers if they appear more than once during the evolution of the star-forming region. We also make predictions for candidate maser transitions at the ALMA frequency range.Comment: 8 pages, 2 figures, to appear in proceedings for IAUS 287: Cosmic Masers - from OH to H

The Australia Telescope campaign to study southern class I methanol masers

The Australia Telescope Compact Array (ATCA) and the Mopra facility have been used to search for new southern class I methanol masers at 9.9, 25 (J=5) and 104 GHz, which are thought to trace more energetic conditions in the interface regions of molecular outflows, than the widespread class I masers at 44 and 95 GHz. One source shows a clear outflow association.Comment: 2 pages, 1 figure (composed from 3 files), to appear in proceedings of IAU Symposium 242 "Astrophysical masers and their environment" (eds. J. Chapman and W. Baan

Advances in Calibration and Imaging Techniques in Radio Interferometry

This paper summarizes some of the major calibration and image reconstruction techniques used in radio interferometry and describes them in a common mathematical framework. The use of this framework has a number of benefits, ranging from clarification of the fundamentals, use of standard numerical optimization techniques, and generalization or specialization to new algorithms

Tolerance and challenges of intercultural interaction among students

The paper presents the research results on correlation between the parameters of communicative tolerance and intercultural adaptation of international students in a multinational university (Tomsk Polytechnic University (TPU). 42 respondents took part in the research from different parts of the world: Asia (China), Africa, the countries of Central Asian region. The level of communicative tolerance was measured with the following techniques: «General communicative tolerance» by V. V. Boyko, the questionnaire of human adaptation to new socio-cultural environment by L. V. Yankovsky, Kruskal-Wallis one way analysis of variance was used for statistics. The study reveals that high rate of communicative tolerance, as a whole, has positive impact on intercultural adaptation of international students in Russia. Рассмотрены результаты исследования взаимоотношения параметров коммуникативной толерантности и межкультурной адаптации иностранных студентов в мультинациональном университете (на примере Томского политехнического университета). В исследовании приняли участие 42 респондента из различных частей Мира: Азия (Китай), Африка, страны Центрально-азиатского региона. Уровень коммуникативной толерантности измерялся с использованием следующих техник: «Общая коммуникативная толерантность» по В. В. Бойко, опрос личностной адаптации к новому культурно-социальному окружению по Л. В. Янковскому; для обработки статистических данных была использована методика «Kruskal-Wallis one way analysis of variance». Исследование выявило, что высокий уровень коммуникативной толерантности в целом оказывает положительное влияние на межкультурную адаптацию иностранных студентов в России

Model Checking Probabilistic Pushdown Automata

We consider the model checking problem for probabilistic pushdown automata (pPDA) and properties expressible in various probabilistic logics. We start with properties that can be formulated as instances of a generalized random walk problem. We prove that both qualitative and quantitative model checking for this class of properties and pPDA is decidable. Then we show that model checking for the qualitative fragment of the logic PCTL and pPDA is also decidable. Moreover, we develop an error-tolerant model checking algorithm for PCTL and the subclass of stateless pPDA. Finally, we consider the class of omega-regular properties and show that both qualitative and quantitative model checking for pPDA is decidable