This article is devoted to the last decades of the existence of the independent Novgorod Republic and its fall. The events of 1470–1471, namely, the attempts to call into service a prince from ...Lithuania, to conclude an alliance with Lithuania and with the Teutonic Order in Livonia, and the campaign of Ivan III and the military defeat of Lord Novgorod the Great, have been considered on a wide background of social and political development of Novgorod the Great throughout the fifteenth century, in the context of the history of its foreign relations and the position of its neighbors, the organization of its armed forces, with a comprehensive account of a variety of sources (not only chronicles but also charters, epistolary and literary sources, etc.) and a rich research literature. In contrast to the approaches widespread in historiography, emphasis has been placed on contemporary reliable sources rather than on later ideological interpretations. Analysis of the chronicles also involves textual criticism. The authors have come to the conclusion that the defeat of the Novgorod Republic was caused not only by social, particularly religious, conflicts that were emphasized by the Moscow side but rather by the complex international situation, which the military and political organization of Novgorod was no longer consistent with, and the inability of the opposing pro-Moscow and pro-Lithuanian parties to offer a convincing ideological line and, consequently, strategy of action in these circumstances.
A
bstract
The quantum interference between the decays of entangled neutral kaons is studied in the process
ϕ
→ K
S
K
L
→
π
+
π
−
π
+
π
−
, which exhibits the characteristic Einstein-Podolsky-Rosen ...correlations that prevent both kaons to decay into
π
+
π
−
at the same time. This constitutes a very powerful tool for testing at the utmost precision the quantum coherence of the entangled kaon pair state, and to search for tiny decoherence and
CPT
violation effects, which may be justified in a quantum gravity framework.
The analysed data sample was collected with the KLOE detector at DAΦNE, the Frascati
ϕ
-factory, and corresponds to an integrated luminosity of about 1.7 fb
−
1
, i.e. to about 1
.
7 × 10
9
ϕ
→ K
S
K
L
decays produced. From the fit of the observed ∆
t
distribution, being ∆
t
the difference of the kaon decay times, the decoherence and
CPT
violation parameters of various phenomenological models are measured with a largely improved accuracy with respect to previous analyses.
The results are consistent with no deviation from quantum mechanics and
CPT
symmetry, while for some parameters the precision reaches the interesting level at which — in the most optimistic scenarios — quantum gravity effects might show up. They provide the most stringent limits up to date on the considered models.
The paper presents the results of analysis of astroclimatic conditions in the Big Telescope Alt-azimuthal (BTA) region (40°N–50°N; 35°E–55°E). Using data from the European center for medium-range ...weather forecast ReAnalysis (ERA-5), we estimated the averaged spatial distributions in total cloud cover, vertical integral of mean kinetic energy, vertical component of wind speed, and wind speed shears, as well as inverse values of Richardson number 1/Ri. An extensive region with the development of atmospheric flows is formed south and southeast of BTA in winter. High inverse values of the Richardson number, spatial heterogeneities in vertical wind speed, and significant wind speed shears in the lower atmosphere are observed in this region. In terms of turbulence development over BTA, the best time for astronomical observations falls in summer, when vertical shears of wind speed are weakened in the lower atmospheric layers. The situation is opposite in the upper troposphere. In winter, BTA is in the region of moderate vertical wind shears. In summer, a region with increased vertical wind speed shears is formed. Taking into account that the intensity of optical turbulence decreases rapidly with height, better image quality can be expected in summer. Such structure of the atmosphere does not allow one to directly apply atmospheric models in order to describe turbulence based on the turbulence strength as function of its ground values, or to use the classical model describing the turbulence velocity as function of air flow velocity at the height corresponding to the 200 hPa level.
Abstract
Based on generalizations of numerous measurements and calculations, the influence of the low-frequency part of the atmospheric turbulence spectrum, directly adjacent to the inertial ...interval, on the statistical characteristics of fluctuations of optical waves propagating in the atmosphere is analyzed. The measured atmospheric turbulence spectra are compared with isotropic models. The outer scale of turbulence in the surface layer of the atmosphere is found to be dependent not only on the height above the underlying surface but also on the type of atmospheric stratification. The influence of the low-frequency part of the atmospheric turbulence spectrum on the phase fluctuations of optical waves propagating both along horizontal paths and obliquely through the entire atmosphere is analyzed.
Approaches to constructing algorithms for controlling adaptive optics (AO) systems based on prediction of evolutions of spatial and temporal distributions of phase distortions in the optical wave ...propagating in an atmospheric turbulence and generation of control signals for correcting wavefront distortions in real time are described. Main patterns of evolutions of phase distortions of optical waves propagating in the Kolmogorov-type turbulent atmosphere are analyzed. An extremely high operating frequency of the Shack–Hartmann-type wavefront sensor has been estimated. Numerical modeling of the AO system operation has been performed in closed and open tracking loops. Errors in estimating the turbulence parameters with the wavefront sensor operating at high frequencies are given.
A film adhesive based on dicyanoether of diphenylolpropane and polysulfone has been developed. The strength characteristics of the film have been studied. The operability of the resulting adhesive ...joints up to a temperature of 230°C with high strength is shown. The dependence of the glass-transition temperature of the cured adhesive on the curing temperature has been studied. The presence of a certain water resistance of the adhesive joint and the cured adhesive has been shown.
Dynamic (time) characteristics of adaptive optics (AO) systems operating in a turbulent atmosphere are analyzed using analytical calculations of the Strehl ratio based on results of the theory of ...optical wave propagation in randomly inhomogeneous media. The analysis involves the model of the active mirror-corrector. The traditional AO system with a finite actuation time is described as a dynamic system with constant delay. In such a system, the permissible time delay is comparable with the time of transport of turbulent inhomogeneities by wind with the mean velocity to a distance equal to the coherence radius. An expression relating in a single formula the most important parameters of the system (the accuracy and operation frequency of the wavefront sensor and the aperture size of the optical system) and the atmosphere parameters (the Fried parameter and wind velocity with the achievable level of the Strehl ratio) is obtained. The differences between two types of tracking loops (open and closed) in AO systems are analyzed. Possibilities of the predictive algorithm for adaptive correction are demonstrated.
In connection with the wide use of optoelectronic systems, we review the development of adaptive optics as an effective tool that allows using controllable optical elements to eliminate irregular ...distortions that occur as light propagates in an inhomogeneous medium. The subject matter of this rapidly developing field of science and technology is described. Of the ideas under development in recent years, many have been around for quite a long time, but it is only now, with the development of an up-to-date optoelectronic element base, that they have started being widely incorporated into science and engineering practice. We discuss the development of adaptive optics from mere ideas to their application in astronomy, high-power laser physics, and medicine. The current state of adaptive optics in stellar and solar astronomy is reviewed, and some results of its use in distortion correction systems of high-power laser systems and facilities are presented.
The scientific work is aimed at finding ways to improve the components of the psychophysical readiness of police officers to use service firearms. In order to solve the research tasks, an analysis of ...the sources of international and domestic law regulating the use of force, special means, and firearms by the police has been carried out, including the UN Code of Conduct for Law Enforcement Officials, the Declaration on the Police, Basic Principles of the Use of Force and Firearms by Officials on maintaining law and order, the Constitution of Ukraine, the Criminal Code of Ukraine, the Law of Ukraine “On the National Police”, Regulations on the organization of official training of employees of the National Police of Ukraine, Instructions on safety measures when handling weapons, Regulations on the organization of initial professional training of police officers who are first accepted on police service.
The algorithm for applying coercive police measures proposed by the UN hs been considered, that is communication – persuasion – physical force – special means – firearms. A comparative characterization of the indicators of firearm owners per 100,000 population abroad with a similar indicator in Ukraine has been carried out. The peculiarities of the legal regulation of the use of coercive police measures in Ukraine under martial law conditions have been determined. The legal, social, domestic and psychophysiological factors that affect the decision-making by police officers on the possibility of using a registered firearm have been given.
Based on the conducted research, the study of special literature, and the analysis of the activities of practical police officers who have at least 5 years of service, it has been established that the components of psychophysical readiness for the use of service firearms are physical, psychological, fire (shooting) and tactical-special training. Ways of a complex combination of the specified areas of psychophysical readiness for the use of service firearms have been proposed.
A
bstract
Using 1.63 fb
−1
of integrated luminosity collected by the KLOE experiment about 7 × 10
4
K
S
→
π
±
e
∓
ν
decays have been reconstructed. The measured value of the charge asymmetry for this ...decay is
A
S
= (−4.9 ± 5.7
stat
± 2.6
syst
) × 10
−3
, which is almost twice more precise than the previous KLOE result. The combination of these two measurements gives
A
S
= (−3.8 ± 5.0
stat
± 2.6
syst
) × 10
−3
and, together with the asymmetry of the
K
L
semileptonic decay, provides significant tests of the
CPT
symmetry. The obtained results are in agreement with
CPT
invariance.
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