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Journal of Applied and Industrial Mathematics 2017年第3期11卷 325-333页

作者： Chaikin, S.V. Institute of System Dynamics and Control Theory ul. Lermontova 134 Irkutsk664033 Russia

Under study in the restricted formulation is the motion of a symmetrical prolate stationary gyrostat along a Keplerian circular orbit in a central Newtonian field of forces. An elastic homogeneous rod, rectilinear in the undeformed state, is rigidly clamped by one end in the body of gyrostat along its axis of symmetry. There is a point mass at the free end of the rod. The inextensible elastic rod, for simplicity of constant circular cross-section, performs infinitesimal space oscillations in the process of system motion. In this case, we neglect the terms in the system’s tensor of inertia which are nonlinear with respect to displacements of the points of the *** consider the following (so-called semi-inverse) problem: Under what kinetic momentumof the flywheel, among the relative equilibriums of the system (the states of rest relative to the orbital coordinate system) does there exist an equilibrium such that the axis, arbitrarily chosen in the coordinate system associated with the gyrostat, is collinear with the local vertical? In the discretization of the problem, we present the values of the Lagrange coordinates that define the deformation of the rod for these equilibria and the value of gyrostatic moment providing the presence of the equilibrium in question. © 2017, Pleiades Publishing, Ltd.

关键词： Inverse problems

Numerical-analytical algorithms for nonlinear optimal control problems on a large time interval 1

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14th International Conference on Dynamical systems: theory and Applications, DSTA 2017

作者： Danik, Yulia Dmitriev, Mikhail Makarov, Dmitry Zarodnyuk, Tatiana pr. 60-letiya Oktyabrya 9 Moscow117312 Russia Matrosov Institute for System Dynamics and Control Theory SB RAS Lermontova str. 134 Irkutsk664033 Russia

ISBN: (数字)9783319965987

ISBN: (纸本)9783319965970

Some nonlinear and discrete optimal control problems with phase constraints on a fixed but sufficiently large time interval are considered as singularly perturbed problems. In continuous-time case the state equations are reduced to singularly perturbed equations on a finite time interval and, in discrete-time case, the state equations have the form of systems with a small step. Using the technique for singularly perturbed systems, the formal asymptotic expansions by the corresponding small parameter are constructed which contain the structural information about the solution. That is usually sufficient for most applications to obtain an initial approximation to control in the global optimum neighborhood. The obtained algorithms can be applied to mathematical economics and technical objects control problems with phase and control constraints, and with turnpike effects in the trajectories, where the turnpike trajectories can be discontinuous. The use of traditional algorithms for these problems is inefficient due to the large increase of computational difficulty. © Springer International Publishing AG, part of Springer Nature 2018.

关键词： Trajectories

Using automatic generation of relaxation constraints to improve the preimage attack on 39-step md4

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arXiv 2018年

作者： Gribanova, Irina Semenov, Alexander Matrosov Institute for System Dynamics and Control Theory Sb Ras Irkutsk Russia

IN this paper we construct preimage attack on the truncated variant of the MD4 hash function. Specifically, we study the MD4-39 function defined by the first 39 steps of the MD4 algorithm. We suggest a new attack on MD4-39, which develops the ideas proposed by H. Dobbertin in 1998. Namely, the special relaxation constraints are introduced in order to simplify the equations corresponding to the problem of finding a preimage for an arbitrary MD4-39 hash value. The equations supplemented with the relaxation constraints are then reduced to the Boolean Satisfiability Problem (SAT) and solved using the state-of-the-art SAT solvers. We show that the effectiveness of a set of relaxation constraints can be evaluated using the black-box function of a special kind. Thus, we suggest automatic method of relaxation constraints generation by applying the black-box optimization to this function. The proposed method made it possible to find new relaxation constraints that contribute to a SAT-based preimage attack on MD4-39 which significantly outperforms the competition. Copyright © 2018, The Authors. All rights reserved.

关键词： Hash functions

Orthogonality-based classification of diagonal Latin squares of order 10 8

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Orthogonality-based classification of diagonal Latin squares...

Selected Papers of the 8th International Conference "Distributed Computing and Grid-Technologies in Science and Education", GRID 2018

作者： Vatutin, Eduard Titov, Vitaly Zaikin, Oleg Kochemazov, Stepan Manzuk, Maxim Nikitina, Natalia Southwest State University Kursk Russia Matrosov Institute for System Dynamics and Control Theory SB RAS Irkutsk Russia BOINC.ru Moscow Russia Institute of Applied Mathematical Research KRCRAS Petrozavodsk Russia

The article describes combinatorial structures based on diagonal Latin squares (DLS) of order 10 and the orthogonality condition between pairs of such squares. These structures are novel and interesting in the context of the well-known open problem aimed at finding a triple of mutually orthogonal DLSs of order 10. The structures were found in the BOINC-based volunteer computing projects SAT@home and Gerasim@home. © 2018 Eduard Vatutin, Vitaly Titov, Oleg Zaikin, Stepan Kochemazov, Maxim Manzuk, Natalia Nikitina.

关键词： Combinatorial mathematics

Approximation results for impulsive control systems with hysteresis

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Approximation results for impulsive control systems with hys...

International Conference on Stability and Oscillations of Nonlinear control systems (Pyatnitskiy's Conference)

作者： O. N. Samsonyuk D. E. Tolkachev Matrosov Institute for System Dynamics and Control Theory of SB RAS Irkutsk Russia

In this paper, impulsive control systems described by measure-driven differential equations with rate independent hysteresis are considered. Approximation results for impulsive processes are presented.

关键词： Hysteresis Trajectory Differential equations Aerospace electronics system dynamics control theory

Necessary optimality conditions for optimal impulsive control problems with hysteresis

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Necessary optimality conditions for optimal impulsive contro...

International Conference on Stability and Oscillations of Nonlinear control systems (Pyatnitskiy's Conference)

作者： O. N. Samsonyuk S. A. Timoshin Matrosov Institute for System Dynamics and Control Theory of SB RAS Irkutsk Russia

We study a class of optimal control problems for measure-driven differential equations with rate independent hysteresis. The hysteresis is modeled by an evolution variational inequality equivalent to the action of play operator generalized to the case of discontinuous inputs of bounded variation. A method to obtain optimality conditions for impulsive processes is proposed.

关键词： Hysteresis Optimal control Trajectory Biological system modeling Process control Differential equations Mathematical model

Towards the baikal open laboratory in astroparticle physics

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arXiv 2019年

作者： Bezyazeekov, Pavel Bychkov, Igor Budnev, Nikolay Chernykh, Daria Kazarina, Yulia Kostunin, Dmitriy Kryukov, Alexander Monkhoev, Roman Shigarov, Alexey Shipilov, Dmitriy Applied Physics Institute Irkutsk State University Irkutsk Russia Matrosov Institute for System Dynamics and Control Theory Siberian Branch of Russian Academy of Sciences Irkutsk Russia DESY Zeuthen Germany Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics Moscow Russia

The open science framework defined in the German-Russian Astroparticle Data Life Cycle Initiative (GRADLCI) has triggered educational and outreach activities at the Irkutsk State University (ISU), which is actively participated in the two major astroparticle facilities in the region: TAIGA observatory and Baikal-GVD neutrino telescope. We describe the ideas grew out of this unique environment and propose a new open science laboratory based on education and outreach as well as on the development and testing new methods and techniques for the multimessenger astronomy. Copyright © 2019, The Authors. All rights reserved.

关键词： Observatories

Data aggregation in the astroparticle physics distributed data storage

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arXiv 2019年

作者： Nguyen, Minh-Duc Kryukov, Alexander Dubenskaya, Julia Korosteleva, Elena Bychkov, Igor Mikhailov, Andrey Shigarov, Alexey Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics 1/2 Leninskie Gory Moscow119991 Russia Matrosov Institute for System Dynamics and Control Theory Siberian Branch of Russian Academy of Sciences Lermontov st. 134 Irkutsk Russia

German-Russian Astroparticle Data Life Cycle Initiative is an international project whose aim is to develop a distributed data storage system that aggregates data from the storage systems of different astroparticle experiments. The prototype of such a system, which is called the Astroparticle Physics Distributed Data Storage (APPDS), has been being developed. In this paper, the Data Aggregation Service, one of the core services of APDDS, is presented. The Data Aggregation Service connects all distributed services of APPDS together to find the necessary data and deliver them to users on demand. Copyright © 2019, The Authors. All rights reserved.

关键词： Life cycle

Metadata extraction from raw astroparticle data of TAIGA experiment

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arXiv 2019年

作者： Bychkov, Igor Dubenskaya, Julia Korosteleva, Elena Kryukov, Alexandr Mikhailov, Andrey Nguyen, Minh-Duc Shigarov, Alexey Matrosov Institute for System Dynamics and Control Theory Siberian Branch of Russian Academy of Sciences Lermontov St. 134 Irkutsk Russia Moscow Russia Institute of Mathematics Economics and Informatics Irkutsk State University Gagarin Blvd. 20 Irkutsk Russia

Today, the operating TAIGA (Tunka Advanced Instrument for cosmic rays and Gamma Astronomy) experiment continuously produces and accumulates a large volume of raw astroparticle data. To be available for the scientific community these data should be well-described and formally characterized. The use of metadata makes it possible to search for and to aggregate digital objects (e.g. events and runs) by time and equipment through a unified interface to access them. The important part of the metadata is hidden and scattered in folder/files names and package headers. Such metadata should be extracted from binary files, transformed to a unified form of digital objects, and loaded into the catalog. To address this challenge we developed a concept of the metadata extractor that can be extended by facility-specific extraction modules. It is designed to automatically collect descriptive metadata from raw data files of all TAIGA formats. Copyright © 2019, The Authors. All rights reserved.

关键词： Metadata

Using the Beth-Uhlenbeck approach to describe the kaon to pion ratio in a 2+1 flavor PNJL model

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arXiv 2019年

作者： Blaschke, D. Friesen, A. Kalinovsky, Yu. Radzhabov, A. Institute for Theoretical Physics University of Wroclaw Wroclaw50-204 Poland Joint Institute for Nuclear Research Dubna Dubna141980 Russia Moscow115409 Russia Matrosov Institute for System Dynamics and Control Theory Irkutsk664033 Russia Irkutsk State University Irkutsk664003 Russia

The kaon to pion ratios are discussed in the framework of a 2+1 flavor PNJL model. In order to interpret the behaviour of bound states in medium the Beth-Uhlenbeck approach is used. It is shown that in terms of phase shifts in the K+ channel an additional low-energy mode could appear as a bound state in medium since the masses of the quark constituents are different. The comparison with experimental data for the ratios is performed and the influence of the anomalous mode to the "horn" effect in the K+/π+ ratio is discussed. Copyright © 2019, The Authors. All rights reserved.

关键词： Hadrons