2,700 research outputs found
Stark Broadening of in III Lines in Astrophysical and Laboratory Plasma
Besides the need of Stark broadening parameters for a number of problems in
physics, and plasma technology, in hot star atmospheres the conditions exist
where Stark widths are comparable and even larger than the thermal Doppler
widths. Using the semiclassical perturbation method we investigated here the
influence of collisions with charged particles for In III spectral lines. We
determined a number of Stark broadening parameters important for the
investigation of plasmas in the atmospheres of A-type stars and white dwarfs.
Also, we have compared the obtained results with existing experimental data.
The results will be included in the STARK-B database, the Virtual Atomic and
Molecular Data Center and the Serbian Virtual Observatory
Exploring barriers to 'Respondent driven sampling' in sex worker and drug-injecting sex worker populations in Eastern Europe
Respondent driven sampling (RDS) has been used in several counties to sample injecting drug users, sex workers (SWs) and men who have sex with men and as a means of collecting behavioural and biological health data. We report on the use of RDS in three separate studies conducted among SWs between 2004 and 2005 in the Russian Federation, Serbia, and Montenegro. Findings suggest that there are limitations associated with the use of RDS in SW populations in these regions. Findings highlight three main factors that merit further investigation as a means of assessing the feasibility and appropriateness of RDS in this high risk population: the network characteristics of SWs; the appropriate level of participant incentives; and lack of service contact. The highly controlled and hidden nature of SW organizations and weak SW social networks in the region can combine to undermine assumptions underpinning the feasibility of RDS approaches and potentially severely limit recruitment. We discuss the implications of these findings for recruitment and the use of monetary and non-monetary incentives in future RDS studies of SW populations in Eastern Europe
Event anisotropy in 4.2A GeV/c C+C collisions
The directed and elliptic flow of protons and negative pions in 4.2A GeV/c
C+C collisions is studied using the Fourier analysis of azimuthal
distributions. It is found that the protons exhibit pronounced directed flow,
while the flow of pions is either non existent or too weak to be detected
experimentally. Also, it is found that in the entire rapidity interval the
elliptic flow is very small if not zero. These results are confirmed by the
Quark-Gluon-String Model (QGSM) and the relativistic transport model (ART 1.0),
except that these models predict very weak antiflow of pions. The more detailed
comparison with the QGSM suggests that the decay of resonances and rescattering
of secondaries dominantly determine the proton and negative pion flow at this
energy.Comment: 7 pages, 3 figures, TeX file changed from double to single-spacin
Opportunities and Weaknesses in Professional Development of Teachers at Secondary Schools of Agriculture in Serbia
Recent developments in market economies have showed that education and human resource creation are among the top priorities of national strategies and social, economic, and technological progress policies. The common denominator of educational reforms in many European countries is an attempt to set up a flexible system for professional education and development to respond to changes in labour market demands. In 2012, the Serbian Government adopted Serbia’s Education Strategy until 2020. This document provides for professional development of teachers and expert assistants at secondary specialist schools. Some of the projected actions involve working out various models of professional development, primarily teacher practice in their respective professions, carried out in companies or institutions. This document focuses on continuing professional development through various forms of formal and informal education.
Success in finding acceptable solutions in food production technology largely depends on educated staff in agriculture and their engagement in transferring their knowledge and technologies to agricultural practice. Secondary school education is most important as it is the education level producing a qualified student who will do a specific job.
The aim of this paper is to address to the need and weaknesses in continuing professional development of teachers at secondary schools of agriculture in Serbia. The weaknesses experienced in practice regarding their development are numerous and often hard to overcome. How to recognise these weaknesses and resolve them is the subject matter of this paper. The paper presents the organizational weaknesses of accredited seminars and their evaluation
Augmented reality in robot programming
Industrial robots have been traditionally programmed using teaching pendants, whereas offline programming methods are getting increasingly popular in recent years. Although the above two methods are widely-used in the industry, they both have certain disadvantages. For instance, the teaching pendant method requires a shutdown of the production line during the programming process, while offline programming method requires 3D CAD models of both the robot and the workpiece. In this paper, an augmented reality (AR) application which alleviates the aforementioned problems was proposed for robot programming purposes. The application is created using commercially available AR software, with the addition of our JavaScript code. The use of commercially available software allows an easier sharing and widespread adoption of the application
Stark Broadening of Several Ne II, Ne III and O III Spectral Lines for the STARK-B Database
In order to complete Stark broadening data for Ne II, and O III lines, needed for analysis of stellar atmospheres, we determined, within the semiclassical perturbation method, the missing Stark broadening parameters for the broadening by collisions with protons and ionized helium, for 15 Ne II and 5 O III multiplets. Also, electron, proton, and ionized helium impact broadening parameters for an important Ne II multiplet in the visible part of the spectrum, and for three Ne III multiplets, were calculated. The obtained data will be included in the STARK-B database, which is a part of Virtual Atomic and Molecular Data Center
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