Математика и физика. Mathematics & Physics. 2021 14 (2)

 

Ресурсы коллекции

  • A Short Essay towards if P not equal NP 

    Rybakov, Vladimir V.; Рыбаков, Владимир В. (Сибирский федеральный университет. Siberian Federal University, 2021)
    We find a computational algorithmic task and prove that it is solvable in polynomial time by a non-deterministic Turing machine and cannot be solved in polynomial time by any deterministic Turing machine. The point is ...

  • Energy Gap Evaluation in Microcrystalline m-HfO2 Powder 

    Shilov, Artem O.; Savchenko, Sergey S.; Vokhmintsev, Alexander S.; Chukin, Andrey V.; Karabanalov, Maksim S.; Vlasov, Maksim I.; Weinstein, Ilya A.; Шилов, Артём О.; Савченко, Сергей С.; Вохминцев, Александр С.; Чукин, Андрей В.; Карабаналов, Максим С.; Власов, Максим И.; Вайнштейн, Илья А. (Сибирский федеральный университет. Siberian Federal University, 2021)
    In this paper optical properties of microcrystalline HfO2 powder are investigated. X-ray diffraction and Raman spectroscopy were used to determine that the studied samples are in monoclinic phase. Based on the analysis ...

  • Supercritical Convection of Water in an Elongated Cavity at a Given Vertical Heat Flux 

    Sharifulin, Vadim A.; Lyubimova, Tatyana P.; Шарифулин, Вадим А.; Любимова, Татьяна П. (Сибирский федеральный университет. Siberian Federal University, 2021)
    The supercritical modes of water convection are investigated at room temperature in an elongated horizontal cavityes, with a width-to-height ratios of 2 : 1 and 3 : 1. The Prandtl number is assumed to be equal to seven. ...

  • Manufacturing of Opals from Polymethylmethacrylate Particles in Dispersion Media with Different Viscosities 

    Nemtsev, Ivan V.; Shabanova, Olga V.; Немцев, Иван В.; Шабанова, Ольга В. (Сибирский федеральный университет. Siberian Federal University, 2021)
    The article was prepared based on the materials of the report at the first All-Russian scientific conference with international participation "YENISEI PHOTONICS – 2020". Photonic crystals are structures that have a spatial ...

  • Steel 110G13L. Thermomagnetic and Galvanomagnetic Effects in its Films 

    Fadeev, Timur V.; Dorokhin, Mikhail V.; Kuznetsov, Iurii M.; .Kveglis, Lyudmila I.; Shevchuk, Vladimir V.; Фадеев, Тимур В.; Дорохин, Михаил В.; Кузнецов, Юрий М.; Квеглис, Людмила И.; Шевчук, Владимир В. (Сибирский федеральный университет. Siberian Federal University, 2021)
    The article shows the ability to control magnetic properties due to modulation of phases in the film with varying temperature of growth. So, at low growth temperatures, a film is formed with an axis of easy magnetization ...

  • Joint Distribution of the Number of Vertices and the Area of Convex Hulls Generated by a Uniform Distribution in a Convex Polygon 

    Khamdamov, Isakjan M.; Chay, Zoya S.; Хамдамов, Исакжан М.; Чай, Зоя С. (Сибирский федеральный университет. Siberian Federal University, 2021)
    A convex hull generated by a sample uniformly distributed on the plane is considered in the case when the support of a distribution is a convex polygon. A central limit theorem is proved for the joint distribution of the ...

  • Numerical and Analytical Modeling of Centrifugal Pump 

    Ivanov, Viktor A.; Erkaev, Nikolay V.; Иванов, Виктор А.; Еркаев, Николай В. (Сибирский федеральный университет. Siberian Federal University, 2021)
    A mathematical model of non-stationary rotation modes of the rotor of a centrifugal pump is constructed. It is based on preliminary calculation in ANSYS Fluent package with subsequent analytical calculation taking into ...

  • Photostability of CdTe Quantum Dots and Graphene Quantum Dots under their Continuous Visible and UV Irradiation 

    Goryunova, Melina A.; Tsipotan, Aleksei S.; Slabko, Vitaliy V.; Горюнова, Мелина А.; Ципотан, Алексей С.; Слабко, Виталий В. (Сибирский федеральный университет. Siberian Federal University, 2021)
    In the last decade, ultraviolet detectors have received significant attention due to their widespread use in civil and military fields. In this work, we have studied the effect of radiation of different ranges (UV and ...

  • Fixed Points of Set-valued F-contraction Operators in Quasi-ordered Metric Spaces with an Application to Integral Equations 

    Ghasab, Ehsan Lotfali; Majani, Hamid; Rad, Ghasem Soleimani; Гасаб, Эхсан Л.; Маджани, Хамид; Рад, Гасем С. (Сибирский федеральный университет. Siberian Federal University, 2021)
    In this paper, we prove some new fixed point theorems involving set-valued F-contractions in the setting of quasi-ordered metric spaces. Our results are significant since we present Banach contraction principle in a ...

  • Method for Determining the Mass Flow for Pressure Measurements of Gas Hydrates Formation in the Well 

    Borisova, Natalya N.; Rozhin, Igor I.; Борисова, Н.Н.; Рожин, И.И. (Сибирский федеральный университет. Siberian Federal University, 2021)
    The work focuses on the inverse problem of determining differential equation coefficients for additional information on the behavior of solution. Furthermore, the algorithm for determining parameters of systems of ordinary ...

  • Asymptotic Behavior of Small Perturbations for Unsteady Motion an Ideal Fluid Jet 

    Andreev, Viktor K.; Андреев, Виктор К. (Сибирский федеральный университет. Siberian Federal University, 2021)
    The stability problem of unsteady rotating circular jet motion of an ideal fluid is reduced to solving an initial-boundary value problem for Poincare–Sobolev type equation with an evolutionary condition on the jet free ...

  • On the Theory of ψ-Hilfer Nonlocal Cauchy Problem 

    Almalahi, Mohammed A.; Panchal, Satish K.; Альмалахи, Мохаммед А.; Панчал, Сатиш К. (Сибирский федеральный университет. Siberian Federal University, 2021)
    In this paper, we derive the representation formula of the solution for ψ-Hilfer fractional differential equation with constant coefficient in the form of Mittag-Leffler function by using Picard’s successive approximation. ...

  • Simulation of Broadening the Second Harmonic Spectrum in KDP by Chirp Pulse Pumping 

    Alekseev, Sergey V.; Losev, Valery F.; Grudtsyn, Yakov V.; Koribut, Andrey V.; Trofimov, Vyacheslav A.; Алексеев, Сергей В.; Лосев, Валерий Ф.; Грудцын, Яков В.; Корибут, Андрей В.; Трофимов, Вячеслав А. (Сибирский федеральный университет. Siberian Federal University, 2021)
    The conditions of broadening the second harmonic spectrum in KDP upon pumping by a negatively chirped pulse of fundamental frequency with central wavelength of 950 nm are analyzed numerically. It is shown that broadening ...

  • Solvability of BVPs for the Parabolic-Hyperbolic Equation with Non-linear Loaded Term 

    Abdullaev, Obidjon Kh.; Абдуллаев, Обиджон (Сибирский федеральный университет. Siberian Federal University, 2021)
    This work is devoted to prove the existence and uniqueness of solution of BVP with non-local assumptions on the boundary and integral gluing conditions for the parabolic-hyperbolic type equation involving Caputo derivatives. ...