458 research outputs found

    Use of information technology to increase economic efficiency and credibility in public administration in the context of digitization

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    Purpose: The article analyzes the use of information technologies to increase the level of economic efficiency and trust in public administration in Ukraine. Design/Methodology/Approach: We use the concept of digital management for the purpose of integrated interaction of municipal and state structures with business, civil society institutions and the population. Findings: The conducted research concludes the active digital transformation of public administration in Ukraine. The following trends in the use of information technology are identified: the development of institutional support; the creation of analytical portals for ensuring public control; the level of accountability, transparency, accountability of the activity of civil servants; the implementation of e-government projects; the changing philosophy of development of electronic services. Practical Implications: The concept of state policy in the field of digital infrastructure was developed on the basis of a multi-stakeholder approach according to which the main purpose of the state bodies is to identify, prioritize, harmonize and satisfy the stakeholders. Originality/Value: In this article, we show the level of individual regions in Ukraine where there is uneven implementation and use of e-learning tools management.peer-reviewe

    About the possibility of five-dimensional effective theories for low-energy QCD

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    The AdS/QCD models suggest an interesting idea that the effective theory of low-energy QCD may be formulated as a 5-dimensional field theory in the weak coupling regime in which the fifth coordinate plays a role of inverse energy scale. Taking the point of view that this is just an efficient parametrization of the non-perturbative dynamics of strong interactions, we discuss on a qualitative level an alternative possibility for a simpler 5-dimensional parametrization of main phenomena in the low-energy QCD. We propose to interpret the effect of chiral symmetry breaking as an effective appearance of compactified extra dimension with the radius of the order of inverse scale of chiral symmetry breaking. Following some heuristic arguments two dual scenarios for the emergence of the excited light mesons are introduced: In the first scenario, the meson resonances are interpreted as the effects of Kaluza-Klein excitations of quarks inside mesons, in the second one, as the formation of gluon strings wound around the compactified dimension an appropriate number of times. Matching of these scenarios permits to express the slope of radial Regge trajectories through the order parameters of the chiral symmetry breaking, with the compactification radius being excluded. This example shows qualitatively that the extra dimension may play an auxiliary role providing a short way for deriving new relations.Comment: 11 pages, accepted by Eur. Phys. J.

    Dephasing of Electrons on Helium by Collisions with Gas Atoms

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    The damping of quantum effects in the transport properties of electrons deposited on a surface of liquid helium is studied. It is found that due to vertical motion of the helium vapour atoms the interference of paths of duration tt is damped by a factor exp(t/τv)3\exp - (t/\tau_v)^3. An expression is derived for the weak-localization lineshape in the case that damping occurs by a combination of processes with this type of cubic exponential damping and processes with a simple exponential damping factor.Comment: 7 pages, 2 figures, Revte

    Is weak temperature dependence of electron dephasing possible?

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    The first-principle theory of electron dephasing by disorder-induced two state fluctuators is developed. There exist two mechanisms of dephasing. First, dephasing occurs due to direct transitions between the defect levels caused by inelastic electron-defect scattering. The second mechanism is due to violation of the time reversal symmetry caused by time-dependent fluctuations of the scattering potential. These fluctuations originate from an interaction between the dynamic defects and conduction electrons forming a thermal bath. The first contribution to the dephasing rate saturates as temperature decreases. The second contribution does not saturate, although its temperature dependence is rather weak, T1/3\propto T^{1/3}. The quantitative estimates based on the experimental data show that these mechanisms considered can explain the weak temperature dependence of the dephasing rate in some temperature interval. However, below some temperature dependent on the model of dynamic defects the dephasing rate tends rapidly to zero. The relation to earlier studies of the dephasing caused by the dynamical defects is discussed.Comment: 14 pages, 6 figures, submitted to PR

    Dephasing Times in a Non-degenerate Two-Dimensional Electron Gas

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    Studies of weak localization by scattering from vapor atoms for electrons on a liquid helium surface are reported. There are three contributions to the dephasing time. Dephasing by the motion of vapor atoms perpendicular to the surface is studied by varying the holding field to change the characteristic width of the electron layer at the surface. A change in vapor density alters the quasi-elastic scattering length and the dephasing due to the motion of atoms both perpendicular and parallel to the surface. Dephasing due to the electron-electron interaction is dependent on the electron density.Comment: 4 pages, Revte

    Features of radiation changes in electrical properties of InAlN/GaN HEMTs

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    The effect of the proton, electron, gamma - rays, and fast neutron irradiation on the parameters of InAlN/Ga

    Wigner function properties for electromagnetic systems

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    Using the Wigner-Vlasov formalism, an exact 3D solution of the Schr\"odinger equation for a scalar particle in an electromagnetic field is constructed. Electric and magnetic fields are non-uniform. According to the exact expression for the wave function, the search for two types of the Wigner functions is conducted. The first function is the usual Wigner function with a modified momentum. The second Wigner function is constructed on the basis of the Weyl-Stratonovich transform in papers [Phys. Rev. A 35 2791 (1987)] or [Phys. Rev. B 99 014423 (2019)]. It turns out that the second function, unlike the first one, has areas of negative values for wave functions with the Gaussian distribution (Hudson's theorem). On the one hand, knowing the Wigner functions allows one to find the distribution of the mean momentum vector field and the energy spectrum of the quantum system. On the other hand, within the framework of the Wigner-Vlasov formalism, the mean momentum distribution and the magnitude of the energy are initially known. Consequently, the mean momentum distributions and energy values obtained according to the Wigner functions can be compared with the exact momentum distribution and energy values. This paper presents this comparison and describes the differences. For the first Wigner function, an analog of the Moyal equation with an electromagnetic part and the Hamilton-Jacobi operator equation are obtained. An operator analogue of the {\guillemotleft}motion equation{\guillemotright} with electromagnetic interaction is constructed. For the second Vlasov equation, an operator expression for the Vlasov-Moyal approximation for systems with electromagnetic interaction is obtained.Comment: 26 pages, 2 figure

    The Wigner function negative value domains and energy function poles of the polynomial oscillator

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    For a quantum oscillator with the polynomial potential an explicit expression that describes the energy distribution as a coordinate (and momentum) function is obtained. The presence of the energy function poles is shown for the quantum system in the domains where the Wigner function has negative values.Comment: 21 pages, 4 figure
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