Theoretical and methodological approaches to management of resource flow processes of development projects on macro-, mezzo-, microlevels

Paper is devoted to the actual problem of managing resource flows of development projects as complex, unique, and open systems, across the different project lifecycle stages that differ in content and are distributed in space and time. The idea was to create a single throughout system for managing resource flow processes of the long-term projects. The research goal included development of theoretical and methodological approaches that can be used in order to manage the combination of development project resource flows using "order from chaos"paradigm. That includes by-stage organization of resource flow processes on of macro-, meso- and microscale, going from sources and sinks of the chaotic project environment resolve to ordered stages of project life cycles. It is proposed to implement resource flow management in form of the stage and resource-based "project-logistic"relay of a triune movement, ordering and transformation of the resource flow processes. This relay is created within a project-logistic field of project management that change by project phases. Synergetic effects of self-organization and self-control appear in the project logistic field due to horizontal interactions, sharing experience, competences, and values among the stakeholders in course of transforming entropic resource-flow processes into the negentropy processes related to project phase goals (attractors). Results can be used to forecast and develop multilevel resource-flow and process systems arranged by resource sources and sinks, and chaotically ordered for projects in different application areas. Further research perspectives include development of self-control and self-organization forms for development projects stakeholders that would comply with international best practices, and fit corresponding project stages. © Published under licence by IOP Publishing Ltd

Observation of Spin Relaxation Anisotropy in Semiconductor Quantum Wells

Spin relaxation of two-dimensional electrons in asymmetrical (001) AlGaAs quantum wells are measured by means of Hanle effect. Three different spin relaxation times for spins oriented along [110], [1-10] and [001] crystallographic directions are extracted demonstrating anisotropy of D'yakonov-Perel' spin relaxation mechanism. The relative strengths of Rashba and Dresselhaus terms describing the spin-orbit coupling in semiconductor quantum well structures. It is shown that the Rashba spin-orbit splitting is about four times stronger than the Dresselhaus splitting in the studied structure.Comment: 4 pages, 3 figure

Magnetic properties of the GdFeSi - GdTiSi solid solutions

The GdFe1-xTixSi, x=0-0.2 intermetallic compounds with a tetragonal crystal structure of the CeFeSi (P4/nmm)-type have been studied. It was obtained that the lattice parameter c and the Curie temperature increase quickly, whereas the lattice parameter a is almost unchanged in the system with increasing of Ti content. The GdFeSi compound is easily magnetized along the [001] axis, the field of magnetic anisotropy equals to ∼3.8 kOe at T = 90 K. The saturation magnetization does not change in the GdFe1-xTi x Si system. © Published under licence by IOP Publishing Ltd.Russian Science Foundation, RSF: 18-72-10098Support by RSF (Project No. 18-72-10098) is acknowledged

Radioluminescence properties of nanocomposite scintillators with BaF 2 fillers

In this paper, studies of the luminescence properties of nanocrystalline BaF 2 samples synthesized by laser ablation and pulse electron beam evaporation method are presented. The measurements of X-ray excited luminescence (XEL) showed the dependence between luminescence intensity and the shape of the spectrum on the morphology and particle size. Also, studies of X-ray excited luminescence, decay curves and optical transmittance for nanocomposite materials containing BaF 2 nanopowder are presented. Barium fluoride nanopowder, obtained by pulsed electron beam evaporation method is characterized by a lower intensity than the initial microcrystalline powder, but at the same time, XEL spectrum of the nanocomposite material with this nanocrystalline filler is more intense, then that for nanocomposite material with initial powder. © Published under licence by IOP Publishing Ltd

Outbreak of West Nile virus infection, Volgograd Region, Russia, 1999.

From July 25 to October 1, 1999, 826 patients were admitted to Volgograd Region, Russia, hospitals with acute aseptic meningoencephalitis, meningitis, or fever consistent with arboviral infection. Of 84 cases of meningoencephalitis, 40 were fatal. Fourteen brain specimens were positive in reverse transcriptase-polymerase chain reaction assays, confirming the presence of West Nile/Kunjin virus

Fixed points and amenability in non-positive curvature

Consider a proper cocompact CAT(0) space X. We give a complete algebraic characterisation of amenable groups of isometries of X. For amenable discrete subgroups, an even narrower description is derived, implying Q-linearity in the torsion-free case. We establish Levi decompositions for stabilisers of points at infinity of X, generalising the case of linear algebraic groups to Is(X). A geometric counterpart of this sheds light on the refined bordification of X (\`a la Karpelevich) and leads to a converse to the Adams-Ballmann theorem. It is further deduced that unimodular cocompact groups cannot fix any point at infinity except in the Euclidean factor; this fact is needed for the study of CAT(0) lattices. Various fixed point results are derived as illustrations.Comment: 33 page

Large Magnetic Entropy Change in GdRuSi Optimal for Magnetocaloric Liquefaction of Nitrogen

The search for new magnetocaloric materials for application in magnetic refrigerants is highly motivated by high efficiency, reliability, and environmental safety. The values of the magnetocaloric effect MCE and the refrigerant capacity RC for the equiatomic GdRuSi compound were determined to be MCE = 10.7 and 4.94 J/kgK and RC = 336 and 92 J/kg with a change in the field of 0–50 and 0–17 kOe, respectively. These high values of MCE and RC for GdRuSi appear in the region of nitrogen liquefaction temperature of 77.4 K, due to which the compound can be useful in practice. The densities of states and magnetic moments of GdRuSi were calculated theoretically, taking into account strong electron correlations in the 4f Gd shell. The total magnetic moment of GdRuSi was found to be composed of the Gd moment only with the value calculated in very good agreement with the experimental one. © 2023 by the authors.Ministry of Education and Science of the Russian Federation, Minobrnauka: 122021000034-9, 122021000039-4; Russian Science Foundation, RSF: 18-72-10098The results of Section 1, Section 2, Section 3.1 and Section 3.2 (magnetic properties and electronic structure calculations) were obtained within the grant of the Russian Science Foundation No. 18-72-10098, https://rscf.ru/en/project/18-72-10098/ (accessed on 29 December 2022). The results of Section 3.3 were obtained within the state assignment of Ministry of Science and Higher Education of the Russian Federation (themes “Magnet” No. 122021000034-9 and “Electron” No. 122021000039-4)

Surface modulation and back reflection from foil targets irradiated by a Petawatt femtosecond laser pulse at oblique incidence

A significant level of back reflected laser energy was measured during the interaction of ultra-short, high contrast PW laser pulses with solid targets at 30 degrees incidence. 2D PIC simulations carried out for the experimental conditions show that at the laser-target interface a dynamic regular structure is generated during the interaction, which acts as a grating (quasi-grating) and reflects back a significant amount of incident laser energy. With increasing laser intensity above 1018 W/cm(2) the back reflected fraction increases due to the growth of the surface modulation to larger amplitudes. Above 1020 W/cm(2) this increase results in the partial destruction of the quasi-grating structure and, hence, in the saturation of the back reflection efficiency. The PIC simulation results are in good agreement with the experimental findings, and, additionally, demonstrate that in presence of a small amount of pre-plasma this regular structure will be smeared out and the back reflection reduced. (C) 2016 Optical Society of Americ

Consequences of local gauge symmetry in empirical tight-binding theory

A method for incorporating electromagnetic fields into empirical tight-binding theory is derived from the principle of local gauge symmetry. Gauge invariance is shown to be incompatible with empirical tight-binding theory unless a representation exists in which the coordinate operator is diagonal. The present approach takes this basis as fundamental and uses group theory to construct symmetrized linear combinations of discrete coordinate eigenkets. This produces orthogonal atomic-like "orbitals" that may be used as a tight-binding basis. The coordinate matrix in the latter basis includes intra-atomic matrix elements between different orbitals on the same atom. Lattice gauge theory is then used to define discrete electromagnetic fields and their interaction with electrons. Local gauge symmetry is shown to impose strong restrictions limiting the range of the Hamiltonian in the coordinate basis. The theory is applied to the semiconductors Ge and Si, for which it is shown that a basis of 15 orbitals per atom provides a satisfactory description of the valence bands and the lowest conduction bands. Calculations of the dielectric function demonstrate that this model yields an accurate joint density of states, but underestimates the oscillator strength by about 20% in comparison to a nonlocal empirical pseudopotential calculation.Comment: 23 pages, 7 figures, RevTeX4; submitted to Phys. Rev.