956 research outputs found
Processing of basalt fiber production waste
The production of mineral rock wool forms a large proportion of off-test waste products. In addition to the cost of their production, there are costs for processing and utilization, such as transportation, disposal and preservation. Besides, wastes have harmful effect on the environment. This necessitates research aimed to study the stress-related characteristics of materials, their recyclability and use in the production of heat-saving product
Feynman Diagrams and Differential Equations
We review in a pedagogical way the method of differential equations for the
evaluation of D-dimensionally regulated Feynman integrals. After dealing with
the general features of the technique, we discuss its application in the
context of one- and two-loop corrections to the photon propagator in QED, by
computing the Vacuum Polarization tensor exactly in D. Finally, we treat two
cases of less trivial differential equations, respectively associated to a
two-loop three-point, and a four-loop two-point integral. These two examples
are the playgrounds for showing more technical aspects about: Laurent expansion
of the differential equations in D (around D=4); the choice of the boundary
conditions; and the link among differential and difference equations for
Feynman integrals.Comment: invited review article from Int. J. Mod. Phys.
Container traffic: East African case
The article reveals the historical features of foreign trade and its transport support in the East African region. In the course of the study an analysis of the export-import cargo flows structure in East Africa both in the colonial period and at the present time has been carried out. The region infrastructure facilities, including seaports, have been considered, their attractiveness for investments and doing business has been taken into account. The current level of container line service for providing the foreign economic transactions transport component has been shown and the main East African ports by level of line service and container turnover have been identified. The main problems and opportunities for increasing East African trade supplies and their logistics services have been revealed
Quantum parallel dense coding of optical images
We propose quantum dense coding protocol for optical images. This protocol
extends the earlier proposed dense coding scheme for continuous variables
[S.L.Braunstein and H.J.Kimble, Phys.Rev.A 61, 042302 (2000)] to an essentially
multimode in space and time optical quantum communication channel. This new
scheme allows, in particular, for parallel dense coding of non-stationary
optical images. Similar to some other quantum dense coding protocols, our
scheme exploits the possibility of sending a classical message through only one
of the two entangled spatially-multimode beams, using the other one as a
reference system. We evaluate the Shannon mutual information for our protocol
and find that it is superior to the standard quantum limit. Finally, we show
how to optimize the performance of our scheme as a function of the
spatio-temporal parameters of the multimode entangled light and of the input
images.Comment: 15 pages, 4 figures, RevTeX4. Submitted to the Special Issue on
Quantum Imaging in Journal of Modern Optic
Developmental Education for University Students: Ways and Methods of its Organization
This article is devoted to the organization of developmental education of students of higher educational institutions. Based on works by I.A. Zimniaia, T.I. Iliin, V.V. Kraevskii, G.M. Kodzhaspirova, I.Ia. Lerner, I.F. Kharlamov and other researchers, the authors clarified the concept of “developmental education of university students", analyzed its components, systematized domestic and foreign experience in organizing developmental education in a higher educational institution. The article also presents the author’s set of pedagogical conditions, which contributes to the organization of developmental education for university students. This set includes the following components: correction of students' value orientations in the educational process of the university; the development of cognitive activity of students and the construction of the educational process at the university, subject to the requirements of a person-centered approach
CASTOR: Centauro and Strange Object Research in nucleus-nucleus collisions at LHC
We describe the CASTOR detector designed to probe the very forward,
baryon-rich rapidity region in nucleus-nucleus collisions at the LHC. We
present a phenomenological model describing the formation of a QGP fireball in
a high baryochemical potential environment, and its subsequent decay into
baryons and strangelets. The model explains Centauros and the long-penetrating
component and makes predictions for the LHC.
Simulations of Centauro-type events were done. To study the response of the
apparatus to new effects different exotic species (DCC, Centauros, strangelets
etc.) were passed through the deep calorimeter. The energy deposition pattern
in the calorimeter appears to be a new clear signature of the QGP.Comment: Talk given by E. Gladysz-Dziadus for the CASTOR group, Intern.
Workshop on Nuclear Theory, 10-15 June, 2002, Bulgaria, Rila Mountains, 15
pages, 14 figure
Medium effects in the production and pi0 gamma decay of omega-mesons in pA collisions in the GeV region
The omega-resonance production and its pi0 gamma decay in p-A reactions close
to threshold is considered within the Intranuclear Cascade (INC) Model. The pi0
gamma invariant mass distribution shows two components which correspond to the
omega decay 'inside' and 'outside' the nucleus, respectively. The 'inside'
component is distorted by medium effects, which introduce a mass shift as well
as collisional broadening for the omega-meson and its decaying pion. The
relative contribution of the 'inside' component is analyzed in detail for
different kinematical conditions and nuclear targets. It is demonstrated that a
measurement of the correlation in azimuthal angle between the pi0 and gamma
momenta allows to separate events related to the 'inside' omega decay from
different sources of background when uncorrelated pi0's and gamma's are
produced.Comment: 24 pages, 11 figure
Исследования микроспоридий рода Nosema в Томской области (Сибирь): ко-инвазия широко распространена в пчелиных семьях
Microsporidian protozoans Nosema are gut parasites that infect European honeybees (Apis mellifera) worldwide. In the Tomsk region, two species of microsporidia were registered in honeybees (A. mellifera): N. apis and N. ceranae. During the last 6 years, an increase in infections by Nosema in honeybees has been detected in the Tomsk region, while cases of mass bee colony deaths were rare (in 2016, two cases of winter losses of bee colonies in the northern districts of the Tomsk region have been reported by beekeepers). The infestation of bee colonies and apiaries have changed from 0% in 2012 to about 80% in 2016-2017. In 2013-2014, 60.0% of all infected apiaries were infected only with N. apis. In 2015-2017, most of the infected apiaries (52.2%) were infected with both species of microsporidia. Despite the predominance of co-infection in honeybees, replacement of N. apis by N. ceranae is not observed
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