6,413 research outputs found
On the relationship between the phases of 27-day total ozone and solar activity indices in different latitudinal zones
The dynamics of 27 day total ozone variations during and 11 year solar activity cycle at high and low latitudes was analyzed. The calculations were made using a specially worked out program permitting, besides the determination of the amplitudes and phases, the observation of the coherence of phases in any time interval. To characterize solar activity, solar radio-flux at 10.7 cm was used. The results of the calculation of total ozone phases difference and those of the index F(sub 10.7), as well as the amplitudes of the 27 day variations of these parameters are presented
Estimate of the possibility of conducting mass spectrometric measurements of the matter of lunar surface
Electron beams studied for use in lunar soil spectrometric analysi
On the D-wave state component of the deuteron in the Nambu-Jona-Lasinio model of light nuclei
The D-wave state component of the neutron-proton bound state in the deuteron
is calculated in the Nambu-Jona-Lasinio model of light nuclei - the
relativistically covariant quantum field theoretic approach to the description
of low-energy nuclear forces. The theoretical value of the fraction of the
D-wave state relative to the S-wave state is equal to eta_d = 0.0238. This
agrees well with the phenomenological value eta_d = 0.0256(4) quoted by
Kamionkowski and Bahcall (ApJ. 420, 884 (1994)).Comment: 7 pages, latex, no figure
A combinatorial approach to the set-theoretic solutions of the Yang-Baxter equation
A bijective map , where
is a finite set, is called a \emph{set-theoretic solution of the Yang-Baxter
equation} (YBE) if the braid relation
holds in A non-degenerate involutive solution satisfying
, for all , is called \emph{square-free solution}. There
exist close relations between the square-free set-theoretic solutions of YBE,
the semigroups of I-type, the semigroups of skew polynomial type, and the
Bieberbach groups, as it was first shown in a joint paper with Michel Van den
Bergh.
In this paper we continue the study of square-free solutions and the
associated Yang-Baxter algebraic structures -- the semigroup , the
group and the - algebra over a field , generated by
and with quadratic defining relations naturally arising and uniquely
determined by . We study the properties of the associated Yang-Baxter
structures and prove a conjecture of the present author that the three notions:
a square-free solution of (set-theoretic) YBE, a semigroup of I type, and a
semigroup of skew-polynomial type, are equivalent. This implies that the
Yang-Baxter algebra is Poincar\'{e}-Birkhoff-Witt type algebra,
with respect to some appropriate ordering of . We conjecture that every
square-free solution of YBE is retractable, in the sense of Etingof-Schedler.Comment: 34 page
Time dependent correlations in marine stratocumulus cloud base height records
The scaling ranges of time correlations in the cloud base height records of
marine boundary layer stratocumulus are studied applying the Detrended
Fluctuation Analysis statistical method. We have found that time dependent
variations in the evolution of the exponent reflect the diurnal
dynamics of cloud base height fluctuations in the marine boundary layer. In
general, a more stable structure of the boundary layer corresponds to a lower
value of the - indicator, i.e. larger anti-persistence, thus a set of
fluctuations tending to induce a greater stability of the stratocumulus. In
contrast, during periods of higher instability in the marine boundary, less
anti-persistent (more persistent like) behavior of the system drags it out of
equilibrium, corresponding to larger values. From an analysis of the
frequency spectrum, the stratocumulus base height evolution is found to be a
non-stationary process with stationary increments. The occurrence of these
statistics in cloud base height fluctuations suggests the usefulness of similar
studies for the radiation transfer dynamics modeling.Comment: 12 pages, 6 figures; to appear in Int. J. Mod. Phys. C, Vol. 13, No.
2 (2002
Higher education market in Ukraine
The article analyses key features o f how the higher education market develops in Ukraine. In order to cover the topic on a large scale, we have defined the terms o f education sen’ice and sen’ice differentiation. The analysis o f market structure gives reasons for stating that the higher education market in Ukraine acts under the conditions o f monopolistic competition.У статті розглянуто загальні характеристики розвитку ринку освітніх послуг України. З метою розкриття теми було визначено поняття «освітня послуга» та «диференціація послуги». Аналіз структури ринку дає підстави характеризувати ргінок освітніх послуг України як монополістичну конкуренцію
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