1,265 research outputs found
Evolution of the nucleon structure in the lightest nuclei
The evolution of the nucleon structure as a function of atomic mass A is
considered for the first time for the lightest nuclei, D, 3H, 3He and 4He, with
an approach based on the Bethe-Salpeter formalism. We show that the pattern of
the oscillation of the structure functions ratio r^A(x) = F_2^A/F_2^N(D) varies
with A by changing the position of the cross-over point x_3 in which r^A(x) =
1, unlike the pattern for nuclei with masses A larger than 4, where only the
amplitude of the oscillation changes. In particular we find that the pattern of
F_2(x) modifications is controlled with the values (1 - x_3) = 0.32 (D/N), 0.16
(3He/D) and 0.08 (4He/D). The obtained results follow from the relativistic
consideration of the nuclear structure and allow us to define a whole class of
modifications of the partonic distributions in the nucleon bound in a nucleus.
The EMC effect is explained as a particular case of the considered class.Comment: Preprint of the publication submitted to Physics Letters B. 12 pages
(LaTeX) including 3 encapsulated figure
Two−photon Processes in Organometallic Molecules and Clusters: T−T Absorption of Group IV Metal Complexes
Triplet – triplet absorption of d0 metal complexes was for the first time revealed and studied by means of pulse photolysis and electron-exchange (Dexter) resonant energy transfer energy transfer.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3539
Graphical Analysis of the Growth Rate of National Economies by Considering the Supply Chain Strategy in 25 Countries over the Period From 2000 to 2016
The article presents the graphical analysis of economic indicators for 25 countries: GDP growth rate (%) and GDP per person employed (thousand US dollars) for the period from 1990 to 2016 by considering the supply chain strategy (SCS) and transparency. The authors carried out the decomposition of economic growth rates of selected countries according to the following factors: 1) extensive factors – the growth rate of the capital stock and the size of labor force; 2) intensive factors – RD expenditures; 3) the dynamics of foreign direct investment in the country 4) supply chain strategy. Over the past 16 years, only a few countries from the sample have shown growth of the national economy higher than the growth rates of the world economy. These are China, Turkmenistan, India, Malaysia, and Singapore (their economies grew at a rate of more than 5% per year). The most dynamic renewal of fixed assets can be observed in China, the United States and Japan. At the same time, over the past 10 years China has demonstrated an active investment policy, increasing the investment in fixed assets almost five times. China and India were countries that most actively used the size of labor force as a factor of extensive growth. Korea, Japan, Germany, USA, China and Singapore demonstrated the most dynamic growth in RD expenditures. Despite the non-monotonous dynamics of foreign direct investment in these countries, over the entire period of observation from 1990 to 2017, the United States has been the most attractive country for foreign direct investment. At the same time, the most significant growth in foreign direct investment was recorded in China and, recently, in the United Kingdom
Relating the proton, neutron and deuteron structure functions in the covariant Bethe-Salpeter formalism
The neutron structure function F2n(x) is evaluated within the kinematic range
10**(-3)<x<1 from the deuteron and proton data by employing relativistic
theoretical description of F2D(x) and several assumptions on the hihg-x
asymptotics of F2n(x)/F2p(x). It is shown that new measurements of F2D(x) in
the range 0.6<x<0.8 would substantially improve understanding of the relation
between d and u valence quarks in the limit x -> 1.Comment: Revised on January 20, 2004: Modified Figs. 2 and 3 and the reference
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Aerial vehicles detection and recognition for UAV vision system
This article focuses on aerial vehicle detection and recognition by a wide field of view monocular vision system that can be installed on UAVs (unmanned aerial vehicles). The objects are mostly observed on the background of clouds under regular daylight conditions. The main idea is to create a multi-step approach based on a preliminary detection, regions of interest (ROI) selection, contour segmentation, object matching and localization. The described algorithm is able to detect small targets, but unlike many other approaches is designed to work with large-scale objects as well. The suggested algorithm is also intended to recognize and track the aerial vehicles of specific kind using a set of reference objects defined by their 3D models. For that purpose a computationally efficient contour descriptor for the models and the test objects is calculated. An experimental research on real video sequences is performed. The video database contains different types of aerial vehicles: airplanes, helicopters, and UAVs. The proposed approach shows good accuracy in all case studies and can be implemented in onboard vision systems.This publication has been prepared as a part of research carried out by Ryazan State Radio Engineering University under the state contract 2.7064.2017/BCh
The phase free, longitudinal, magnetic component of vacuum electromagnetism
A charge moving in a reference laboratory system with constant velocity
{\bf V} in the -axis produces in the -axis a longitudinal, phase free,
vacuum magnetic field which is identified as the radiated field
of Evans, Vigier and others.Comment: ReVTeX file, 7pp., no figure
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