64 research outputs found
Опыт использования сетевого курса «Физика» для студентов, обучающихся по дистанционной технологии
The implementation of web course on discipline of Physics into distance learning technologies is discussed. The main stages of web course development and implementation into the educational process have been considered. The web course structure is comprehensive and includes theoretical materials, practical training, and laboratory work. It is shown than implementation of web course into distance learning technologies promotes the accessibility of high quality education for students.Статья посвящена применению сетевого курса по дисциплине «Физика» для студентов, обучающихся по дистанционной технологии. Рассмотрены основные этапы разработки и внедрения сетевого курса в образовательный процесс. Структура сетевого курса носит комплексный характер, включающий в себя теоретический материал, практические занятия и лабораторные практикум. Показано, что внедрение сетевых курсов с использованием дистанционных образовательных технологий способствует обеспечению доступности качественного образования студентов
Role of metallurgical factors in structure and property formation for thick plates of alloys of the Al-Cu-Mg-Mn system
The role of chemical composition is studied in thick plate structure and property formation for alloys of the Al-Cu-Mg-Mn system. It is shown that in order to correct the chemical composition of aluminum alloys it is necessary to consider the alloying element compatible solubility limit within an aluminum matrix at the heating temperature for hardening and the proportion of alloying elements participating in forming almost insoluble phases with impurity elements. An important role is also played by alloying elements formed with reaction of excess phases, although they are soluble but cannot be dissolved during heating for hardening due to saturation of α-solid solution with alloying elements. © 2013 Springer Science+Business Media New York
Phase formation during nonequilibrium crystallization of Al-Mg-Si system alloys
Nonequilibrium crystallization of alloys of the Al-Mg-Si system, and also their structure and phase composition in a cast condition are studied. Thermal analysis is used to establish phase transformation temperature ranges, occurring during nonequilibrium crystallization of industrial aluminum alloys AD31 and AD33. x-Ray microanalysis is used to determine metastable phase composition in the alloys in a cast condition. © 2013 Springer Science+Business Media New York
Applying of «Gipermethod» system for studying physics course in full time and distance education
The implementation of «Gipermethod» system for studying physics course in full time and distance education is discussed. The main stages of electronic learning course development and implementation into the educational process have been considered. The course structure is comprehensive and includes theoretical materials, practical training, laboratory work, automated checking test. It is shown than implementation of web course into distance learning technologies promotes the accessibility of high quality education for students.Статья посвящена внедрению системы «Гиперметод» для изучения курса по дисциплине «Физика» для студентов очного, заочного и вечернего обучения. Рассмотрены основные этапы разработки и внедрения электронного обучающего курса в образовательный процесс. Структура курса носит комплексный характер, включающий в себя теоретический материал, практические занятия, лабораторные практикум, автоматизированный тестовый контроль. Показано, что внедрение сетевых курсов с использованием дистанционных образовательных технологий способствует обеспечению доступности качественного образования студентов
Spurious Shear in Weak Lensing with LSST
The complete 10-year survey from the Large Synoptic Survey Telescope (LSST)
will image 20,000 square degrees of sky in six filter bands every few
nights, bringing the final survey depth to , with over 4 billion
well measured galaxies. To take full advantage of this unprecedented
statistical power, the systematic errors associated with weak lensing
measurements need to be controlled to a level similar to the statistical
errors.
This work is the first attempt to quantitatively estimate the absolute level
and statistical properties of the systematic errors on weak lensing shear
measurements due to the most important physical effects in the LSST system via
high fidelity ray-tracing simulations. We identify and isolate the different
sources of algorithm-independent, \textit{additive} systematic errors on shear
measurements for LSST and predict their impact on the final cosmic shear
measurements using conventional weak lensing analysis techniques. We find that
the main source of the errors comes from an inability to adequately
characterise the atmospheric point spread function (PSF) due to its high
frequency spatial variation on angular scales smaller than in the
single short exposures, which propagates into a spurious shear correlation
function at the -- level on these scales. With the large
multi-epoch dataset that will be acquired by LSST, the stochastic errors
average out, bringing the final spurious shear correlation function to a level
very close to the statistical errors. Our results imply that the cosmological
constraints from LSST will not be severely limited by these
algorithm-independent, additive systematic effects.Comment: 22 pages, 12 figures, accepted by MNRA
Measuring the Polarization of a Rapidly Precessing Deuteron Beam
This paper describes a time-marking system that enables a measurement of the
in-plane (horizontal) polarization of a 0.97-GeV/c deuteron beam circulating in
the Cooler Synchrotron (COSY) at the Forschungszentrum J\"ulich. The clock time
of each polarimeter event is used to unfold the 120-kHz spin precession and
assign events to bins according to the direction of the horizontal
polarization. After accumulation for one or more seconds, the down-up
scattering asymmetry can be calculated for each direction and matched to a
sinusoidal function whose magnitude is proportional to the horizontal
polarization. This requires prior knowledge of the spin tune or polarization
precession rate. An initial estimate is refined by re-sorting the events as the
spin tune is adjusted across a narrow range and searching for the maximum
polarization magnitude. The result is biased toward polarization values that
are too large, in part because of statistical fluctuations but also because
sinusoidal fits to even random data will produce sizeable magnitudes when the
phase is left free to vary. An analysis procedure is described that matches the
time dependence of the horizontal polarization to templates based on
emittance-driven polarization loss while correcting for the positive bias. This
information will be used to study ways to extend the horizontal polarization
lifetime by correcting spin tune spread using ring sextupole fields and thereby
to support the feasibility of searching for an intrinsic electric dipole moment
using polarized beams in a storage ring. This paper is a combined effort of the
Storage Ring EDM Collaboration and the JEDI Collaboration.Comment: 28 pages, 15 figures, prepared for Physical Review ST - Accelerators
and Beam
Antimicrobial activity ofspices
The purpose of the study - to analyze the literature data in the field of antimicrobial activity of spices.Цель исследования –проанализировать данные литературы в области антимикробной активности специй
Spin tune mapping as a novel tool to probe the spin dynamics in storage rings
Precision experiments, such as the search for electric dipole moments of
charged particles using storage rings, demand for an understanding of the spin
dynamics with unprecedented accuracy. The ultimate aim is to measure the
electric dipole moments with a sensitivity up to 15 orders in magnitude better
than the magnetic dipole moment of the stored particles. This formidable task
requires an understanding of the background to the signal of the electric
dipole from rotations of the spins in the spurious magnetic fields of a storage
ring. One of the observables, especially sensitive to the imperfection magnetic
fields in the ring is the angular orientation of stable spin axis. Up to now,
the stable spin axis has never been determined experimentally, and in addition,
the JEDI collaboration for the first time succeeded to quantify the background
signals that stem from false rotations of the magnetic dipole moments in the
horizontal and longitudinal imperfection magnetic fields of the storage ring.
To this end, we developed a new method based on the spin tune response of a
machine to artificially applied longitudinal magnetic fields. This novel
technique, called \textit{spin tune mapping}, emerges as a very powerful tool
to probe the spin dynamics in storage rings. The technique was experimentally
tested in 2014 at the cooler synchrotron COSY, and for the first time, the
angular orientation of the stable spin axis at two different locations in the
ring has been determined to an unprecedented accuracy of better than
rad.Comment: 32 pages, 15 figures, 7 table
Phase Measurement for Driven Spin Oscillations in a Storage Ring
This paper reports the first simultaneous measurement of the horizontal and
vertical components of the polarization vector in a storage ring under the
influence of a radio frequency (rf) solenoid. The experiments were performed at
the Cooler Synchrotron COSY in J\"ulich using a vector polarized, bunched
deuteron beam. Using the new spin feedback system, we
set the initial phase difference between the solenoid field and the precession
of the polarization vector to a predefined value. The feedback system was then
switched off, allowing the phase difference to change over time, and the
solenoid was switched on to rotate the polarization vector. We observed an
oscillation of the vertical polarization component and the phase difference.
The oscillations can be described using an analytical model. The results of
this experiment also apply to other rf devices with horizontal magnetic fields,
such as Wien filters. The precise manipulation of particle spins in storage
rings is a prerequisite for measuring the electric dipole moment (EDM) of
charged particles
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