О построении циркулянтных матриц, связанных с MDS-матрицами

The objective of this paper is to suggest a method of the construction of circulant ma-trices, which are appropriate for being MDS (Maximum Distance Separable) matrices utilising in cryptography. Thus, we focus on designing so-called bi-regular circulant matrices, and furthermore, impose additional restraints on matrices in order that they have the maximal number of some element occurrences and the minimal number of distinct elements. The reason to construct bi-regular matrices is that any MDS matrix is necessarily the bi-regular one, and two additional restraints on matrix elements grant that matrix-vector multiplication for the samples constructed may be performed effciently. The results obtained include an upper bound on the number of some ele-ment occurrences for which the circulant matrix is bi-regular. Furthermore, necessary and sucient conditions for the circulant matrix bi-regularity are derived. On the ba-sis of these conditions, we developed an effcient bi-regularity verication procedure. Additionally, several bi-regular circulant matrix layouts of order up to 31 with the maximal number of some element occurrences are listed. In particular, it appeared that there are no layouts of order 32 with more than 5 occurrences of any element which yield a bi-regular matrix (and hence an MDS matrix)

ANALYSIS AND VERIFICATION OF THE OPERATION OF THE STABILIZING ROBUST CONTROLLER'S ELECTRICAL CIRCUIT OF THE ROTOR FLUX-LINKAGE CONTROL SYSTEM

On the basis of the classical theory of robust control, the theory of stability and the theory of continued fractions, the linearized mathematical model, the procedure for calculating and designing an analog electrical circuit of the H∞-suboptimal robust controller of the flux-linkage control system of the rotor of an asynchronous electric drive, protected by Ukrainian Patent no.137157, were built. The circuit contains three operational amplifiers, several resistors and capacitors. The proposed mathematical model, the procedure for calculating and choosing the parameters of the resistors and capacitors of the circuit take into account the random variations of the object and the controller within the specified boundaries. An analytical relationship between the transfer function coefficients and the resistances of the resistors and the capacitances of the capacitors of the controller's electrical circuit was established. On a specific example, by calculation according to the developed algorithm, the limiting values of the tolerances of the circuit's resistances of the resistors and capacitances of the capacitors were identified and these values were selected with a margin from the standard series. Analysis of noise filtering by the electrical circuit of the controller in the Multisim package shows its insensitivity to noise spreads within fairly wide boundaries. На базі класичної теорії робастного управління, теорії стійкості і теорії ланцюгових дробів побудовано лінеаризована математична модель, процедура розрахунку і проектування аналогової електричної схеми Н∞-субоптимального робастного регулятора системи управління потокозчепленням ротора асинхронного електроприводу, що захищена патентом України № 137157. Схема містить три операційних підсилювача, кілька резисторів і конденсаторів. Запропонована математична модель, процедура розрахунку і вибору параметрів резисторів і конденсаторів схеми враховують випадкові варіації об’єкта і регулятора в заданих межах. Встановлено аналітичний зв’язок між коефіцієнтами передавальної функції і опорами резисторів і ємностями конденсаторів електричної схеми регулятора. На конкретному прикладі розрахунковим шляхом за розробленим алгоритмом виявлені граничні значення допусків опорів резисторів і ємностей конденсаторів схеми і здійснений їх вибір із запасом зі стандартних рядів. Аналіз фільтрації завад електричною схемою регулятора в пакеті Multisim показує її нечутливість до розмахів завад у досить широких межах

Конвенция о правовом статусе Каспийского моря: первые итоги

On 12 August 2018, the Fifth Caspian Summit was held in Aktau, Kazakhstan, during which the presidents of Azerbaijan, Iran, Kazakhstan, Russia and Turkmenistan signed a fundamental document for regional cooperation — the Convention on the Legal Status of the Caspian Sea. This comprehensive agreement concludes years of negotiations and enshrines the legal modalities for cooperation between the littoral states in an international legal framework. Its key feature is the harmonious combination of historical principles of interaction between regional actors with new elements in line with modern realities. Since the Convention has laid the foundations for a future-oriented conflict-free model of five-party cooperation based on trust, friendship and good neighborliness, it has come to be compared with the «Constitution of the Caspian Sea» in the expert community.This article provides a structural analysis of the Convention’s provisions and examines its effect on the relationship between the littoral states. The study identifies the reasons that prompted the five Caspian states to start working on the agreement and emphasizes the key role of Russian diplomacy in achieving success in the negotiation process. The author elaborates on the main provisions of the Convention and highlights the areas where the greatest progress has been made. Particular attention is paid to the establishment of a high-level regular consultation mechanism with an emphasis on the development of a methodology for establishing straight baselines in the Caspian Sea area. Interim projections were made regarding possible dates for the Convention’s entry into force. Moreover, the article outlines prospects for holding the Sixth Caspian Summit in Turkmenistan by the end of 2021 and suggests which documents may be adopted at the summit. The author concludes that there is a need to further improve the international legal framework for cooperation and to expand the network of five-party cooperation mechanisms in order to strengthen the sub-regional cooperation model.12 августа 2018 года в казахстанском городе Актау состоялся V Каспийский саммит, в ходе которого президенты Азербайджана, Ирана, Казахстана, России и Туркменистана подписали основополагающий для регионального сотрудничества документ — Конвенцию о правовом статусе Каспийского моря. Данное всеобъемлющее соглашение подводит черту под многолетним переговорным процессом и закрепляет в международно-правовом поле юридический порядок взаимодействия прибрежных стран. Его ключевой особенностью является гармоничное сочетание исторически сложившихся принципов сотрудничества региональных акторов с привнесением новых, отвечающих современным реалиям элементов. Поскольку Конвенция заложила основы устремлённой в будущее бесконфликтной модели пятисторонней кооперации, в основе которой лежат доверие, дружба и добрососедство, в экспертной среде её стали сравнивать с «Конституцией Каспийского моря».В данной статье проводится структурный анализ положений Конвенции, а также исследуется её влияние на взаимоотношения между прибрежными государствами. Выявлены причины, побудившие «каспийскую пятёрку» приступить к выработке данного соглашения, подчёркнута ключевая роль российской дипломатии в достижении успеха на переговорном треке. Детально рассмотрены основные положения Конвенции, отдельно обозначены те области, в которых удалось добиться наибольшего прогресса. Особое внимание уделено формированию механизма регулярных консультаций высокого уровня с акцентом на разработку методики установления прямых исходных линий в каспийской акватории. Сделаны промежуточные прогнозы относительно возможных сроков вступления Конвенции в силу. Обозначены перспективы проведения VI Каспийского саммита в Туркменистане до конца 2021 года, высказаны предположения относительно документов, которые могут войти в «подписной» пакет встречи на высшем уровне.В заключении сделан вывод о необходимости дальнейшего совершенствования международного-правового инструментария сотрудничества и расширения сети пятисторонних кооперационных механизмов в целях укрепления субрегиональной кооперационной модели

Teaching English in the higher education institution: teachers and students perspective

The purpose of the given study is to provide description of English for Specific Purposes (ESP) course implementation in Russian higher educational institutions. The authors consider the experience of ESP training at Ogarev Mordovia State University (Saransk, Russia) and outline the most typical issues faced by ESP teachers in real-life conditions of education process. The following problem aspects are pointed out: appropriate selection and use of training materials for the educational course, multilevel groups issue, necessity of due ESP course design etc. The authors also provide the results of the survey for students of some departments of Mordovia Ogarev State University listing the most relevant issues and challenges faced by them while taking an ESP course. The creators of the paper suggest several ways of solution for the issues stated and provide possible directions for the development and quality improvement of ESP courses in the higher education system of Russia

Feasibility of a Small, Rapid Optical-to-IR Response, Next Generation Gamma Ray Burst Mission

We present motivations for and study feasibility of a small, rapid optical to IR response gamma ray burst (GRB) space observatory. By analyzing existing GRB data, we give realistic detection rates for X-ray and optical/IR instruments of modest size under actual flight conditions. Given new capabilities of fast optical/IR response (about 1 s to target) and simultaneous multi-band imaging, such an observatory can have a reasonable event rate, likely leading to new science. Requiring a Swift-like orbit, duty cycle, and observing constraints, a Swift-BAT scaled down to 190 square cm of detector area would still detect and locate about 27 GRB per yr. for a trigger threshold of 6.5 sigma. About 23 percent of X-ray located GRB would be detected optically for a 10 cm diameter instrument (about 6 per yr. for the 6.5 sigma X-ray trigger).Comment: Elaborated text version of a poster presented at 2012 Malaga/Marbella symposiu

STABILITY AND ACCURACY OF THE ROBUST SYSTEM FOR STABILIZING THE ROTOR FLUX-LINKAGE OF AN ASYNCHRONOUS ELECTRIC DRIVE AT RANDOM VARIATIONS OF THE UNCERTAIN PARAMETERS WITHIN THE SPECIFIED BOUNDARIES

Purpose. The aim is to investigate the stability and the accuracy of a robust system for stabilizing the rotor flux-linkage of an asynchronous electric drive at random variations of the uncertain parameters of the object and the regulator within the specified boundaries. Methodology. To make the research, the mathematical model of the rotor flux-linkage channel of the vector control system of an asynchronous electric drive with parametric uncertainty was applied. The transfer function of the Н∞-suboptimal regulator was calculated using the mixed sensitivity method. This transfer function was used to construct the regulator structural scheme in the form of a connection of proportional and integrating links and several adders. Analytical dependences of the coefficients of the regulator's transfer function on the parameters of links of such a connection are determined. These dependences served to researching the influence of uncertain parameters of the regulator links and the object on the stability of the robust system and the accuracy of flux-linkage stabilization. Results. Investigations of the robust system stability and the accuracy of flux-linkage stabilization in the Robust Control Toolbox are done. The curves of the flux-linkage transient processes and the Bode diagram for the open system at random variations of the indeterminate parameters of the object and the regulator links within the specified boundaries are constructed. A choice of variable parameters was carried out by the Monte Carlo method. By the scatter of the obtained curves of the transient processes, the accuracy of flux-linkage stabilization was determined, and according to the Bode diagram, stability reserves in the amplitude and the phase of the robust system were determined. A high accuracy of flux-linkage stabilization (deviation less than 1 %) in fairly wide ranges of changing the uncertain parameters of the object and the regulator, while maintaining the stability of the system with permissible reserves in amplitude and phase, is established. Originality. For the first time, analytical dependences of the coefficients of the transfer function of the Н∞-suboptimal regulator on the parameters of its structural scheme, which represented in the form of a connection of proportional and integrating links, are obtained. The method for calculating the stability of a robust flux-linkage control system and the accuracy of its stabilization at random variations of the uncertain parameters of the object and the regulator links within the specified boundaries is developed. Practical value. The use of the proposed method allows, during the design of the regulator, to ensure the selection of its elements from standard series

Correction of morphofunctional disorders of the cardiovascular system with asialized erythropoietin and arginase II selective inhibitors KUD 974 and KUD 259 in experimental preeclampsia

The aim of the present study was to study the effectiveness of asialized erythropoietin and arginase II selective inhibitors: KUD-259 and KUD-974 in the correction of morphofunctional disorders of the cardiovascular system in experimental preeclampsi

Mechanism of making legislative decisions in the Russian Federation as a method of economic regulation: based on the analysis of quantitative data of LAWSTREAM.RU database

Objective: to consider the use of legislative decision-making mechanisms in the Russian Federation as a tool of economic regulation on the basis of quantitative data of LAWSTREAM.RU database and to confirm or refute the hypothesis that the failures in the GDP growth dynamics encourage the state regulator to intensify rulemaking.Methods: abstract-logical method, comparison, correlation analysis.Results: the mechanism of legislative decision-making can and should be considered as a tool for the economic regulation policy implementation. The effectiveness of reforms is determined by the way in which the government, as the regulatory body of the economic system, uses the existing mechanisms of legislative decision-making in the field of economic regulation. The paper analyzes the institutional aspects of economic reforms. The authors compare the quantitative dynamics of the law drafts in the sphere of economic relations submitted to the State Duma and adopted by it, and the dynamics of the Russian GDP growth in 1994-2018. The correlation is shown between the macroeconomic situation and the legislative activity of the President and government in economic sphere; the hypothesis is confirmed about the influence of the GDP growth on the President and government’s legislative activity in the sphere of economy and finance regulation in case of sharply negative GDP values. It is established that the peak of the state regulator’s activity in the regulatory sphere is the system reaction to shock, expressed in a sharp drop in GDP growth.Scientific novelty: the article is the first attempt to compare the quantitative indicators of the adopted law drafts in the sphere of economy regulation and the GDP dynamics.Practical significance: the results obtained by the authors are useful for describing the model of legislative influence of the Russian executive authorities on the economic environment, taking into account the current macroeconomic indicators

Quantum phase transition in a minimal model for the Kondo effect in a Josephson junction

We propose a minimal model for the Josephson current through a quantum dot in a Kondo regime. We start with the model that consists of an Anderson impurity connected to two superconducting (SC) leads with the gaps $\Delta_{\alpha}=|\Delta_{\alpha}| e^{i \theta_{\alpha}}$, where $\alpha = L, R$ for the lead at left and right. We show that, when one of the SC gaps is much larger than the others $|\Delta_L| \gg |\Delta_R|$, the starting model can be mapped exactly onto the single-channel model, which consists of the right lead of $\Delta_R$ and the Anderson impurity with an extra onsite SC gap of $\Delta_d \equiv \Gamma_L e^{i \theta_L}$. Here $\theta_L$ and $\Gamma_L$ are defined with respect to the starting model, and $\Gamma_L$ is the level width due to the coupling with the left lead. Based on this simplified model, we study the ground-state properties for the asymmetric gap, $|\Delta_L| \gg |\Delta_R|$, using the numerical renormalization group (NRG) method. The results show that the phase difference of the SC gaps $\phi \equiv \theta_R -\theta_L$, which induces the Josephson current, disturbs the screening of the local moment to destabilize the singlet ground state typical of the Kondo system. It can also drive the quantum phase transition to a magnetic doublet ground state, and at the critical point the Josephson current shows a discontinuous change. The asymmetry of the two SC gaps causes a re-entrant magnetic phase, in which the in-gap bound state lies close to the Fermi level.Comment: 23 pages, 13 figures, typos are correcte

Assessment of the nephroprotective properties of the erythropoietin mimetic peptide and infliximab in kidney ischemia-reperfusion injury in rat

The present study aimed to investigate the protective effects of erythropoietin mimetic peptide (pHBSP) and infliximab on ischemic renal reperfusion injur. The experiment was performed on 70 white male Wistar laboratory rats which received recombinant erythropoietin, pHBSP, and inflixima