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In this paper, we study quantum Ordered Binary Decision Diagrams(OBDD ) model; it is a restricted version of read-once quantum branching programs, with respect to "width" complexity. It is known that the maximal gap between deterministic and quantum complexities is exponential. But there are few examples of functions with such a gap. We present a new technique ("reordering") for proving lower bounds and upper bounds for OBDD with an arbitrary order of input variables if we have similar bounds for the natural order. Using this transformation, we construct a total function REQ such that the deterministic OBDD complexity of it is at least 2 Ω (n / log n) , and the quantum OBDD complexity of it is at most O (n 2 / log n) . It is the biggest known gap for explicit functions not representable by OBDD s of a linear width. Another function(shifted equality function) allows us to obtain a gap 2 Ω (n) vs O (n 2) . Moreover, we prove the bounded error quantum and probabilistic OBDD width hierarchies for complexity classes of Boolean functions. Additionally, using "reordering" method we extend a hierarchy for read-k-times Ordered Binary Decision Diagrams ( k - OBDD ) of polynomial width, for k = o (n / log 3 n) . We prove a similar hierarchy for bounded error probabilistic k - OBDD s of polynomial, superpolynomial and subexponential width. The extended abstract of this work was presented on International Computer Science Symposium in Russia, CSR 2017, Kazan, Russia, June 8 – 12, 2017 Khadiev and Khadieva (2017) [ABSTRACT FROM AUTHOR]

Foreign students coming to study in Russia learn the Russian language at all levels, enriching their vocabulary. Besides possessing the lexical minimum of the Russian language, foreign students studying at the preparatory department of the Russian university need to master specialised terminology used in computer science, physics and mathematics. These subjects are included in the list of disciplines of the supplementary general programme, which aims to provide a preparation course for foreign citizens and stateless persons to master professional educational programmes in the Russian language. This article describes the need and conditions for enriching and activating the vocabulary of foreign students, while providing a general description of research methods. It expounds on the structure and content of the computer science course at the pre-university stage of training for foreign citizens. The paper considers the process of teaching foreign studentsthe terminology used in the computer science course. This paper provides a number of examples of new terms as well as exercises related to their acquisition. It is concluded that teaching computer-science vocabulary to foreign students is one of the most important components of teaching information science and expanding the learners’ vocabulary in general. [ABSTRACT FROM AUTHOR]