Statistical Analysis of Precipitation Events

In the present paper we demonstrate the results of a statistical analysis of some characteristics of precipitation events and propose a kind of a theoretical explanation of the proposed models in terms of mixed Poisson and mixed exponential distributions based on the information-theoretical entropy reasoning. The proposed models can be also treated as the result of following the popular Bayesian approach.Comment: 5 pages, 4 figures; ICNAAM 201

Effects of factors of prolonged space flight on conditions of tortoise skeleton

After a 60-90 day space flight mild osteoporosis developed in the epiphyses and metaphyses of long tubular bones of tortoises, which was not attributed to reduced mineral saturation of the preserved bone tissue microstructures. The diminished strength of the cancellous bone of the epiphyses in tortoises after space flight was due to the reduced properties of its structure. The strength of the compact substance did not change under the effect of weightlessness

Guided random walk calculation of energies and <\sq {r^2} > values of the 1Σg^1\Sigma_g state of H_2 in a magnetic field

Energies and spatial observables for the $^1\Sigma_g$ state of the hydrogen molecule in magnetic fields parallel to the proton-proton axis are calculated with a guided random walk Feynman-Kac algorithm. We demonstrate that the accuracy of the results and the simplicity of the method may prove it a viable alternative to large basis set expansions for small molecules in applied fields.Comment: 10 pages, no figure

Flax Growing in Tyumen Region: History of Formation and Development in XX Century

The aspects of the origin, formation and development of the flax-growing industry in the Tyumen region in the ХХ century are considered. Based on the available historiographic material (articles, reports, essays, descriptions, statistical information), the authors identified the features of the formation of the industry. It is noted that the historical conditions in which the Tobolsk (Tyumen) province was located, later the region, throughout the XX century, were full of contradictions and difficulties. It is argued that, having good potential, having received an impetus for development in the middle of the last century, at present, flax growing has not become one of the most important sectors of the economy. It is shown that the publications of the Tobolsk Provincial Statistical Committee: “Reviews of the Tobolsk Governorate”, “Reviews of the Tobolsk Governorate in the Agricultural Relationship”, the works of N. L. Skalozubova — reveal the state of agricultural life of the population of the province, the research potential of the Tyumen experimental station, the advanced experience of agricultural enterprises, allow to identify the main problems and prospects for growing flax in the region. The productivity of flax in various agro-ecological zones of the region, varietal potential and the degree of its realization, taking into account climatic features over a long period, the economic feasibility of growing both fiber and oil-bearing forms are analyzed. The main stages of development of flax growing and limiting factors for the production of high-quality flax products are identified

Multiplexing signals with twisted photons by a circular arc phased array

The theory of multiplexing electromagnetic signals by means of twisted photons generated by a uniform circular array is developed in the case when the receiving antenna represents an array of elements located on a circular arc. The notion of discrete twisted photons of the order $N$ is introduced and orthogonality of these modes modulo $N$ is established. Both paraxial and planar discrete twisted photons are considered. It is shown that in the simplest scenario a $K$ times decrease of the circular arc where the receiving array antenna is placed results in a $K$ times decrease of the number of independent information channels. In the more sophisticated approach, one can restore all $N\gg1$ independent information channels in receiving the signal by an array antenna with $N$ elements located on a circular arc with the central angle $2\pi/K$. However, this problem becomes rapidly ill-conditioned as one increases $K$. The method mitigating this issue is described. The estimates for the corresponding condition numbers are found.Comment: 15 pp., 3 fig

Historical Aspects of the Development of Flax Growing in the Tobolsk Province in the Second Half of the XIX Century

The article is devoted to the history of flax growing and consideration of the experience of its development as an agricultural sector in the Tobolsk province. The material was the reviews, reports, descriptions and recommendations identified by the authors and devoted to this area of agriculture in the second half of the 19th century, among them: “Reviews of the Tobolsk province”, “Report on flax growing, flax production and flax trade in the northern region” by P. P. Chubinsky, “Instructions on how to benefit from agriculture or a description of the Turin district of the Tobolsk province economically” by priest M. Popov, “Harvest of grain in the Tobolsk province in 1894 and brief information about the state of agriculture” by N. L. Skalozubov. It is noted that the considered chronological period is poorly covered in the available literature, which contains only statistical information on the number of collected breads received from volost boards and from the appendices to the governor's reports. It is reported that the analysis of the situation in agriculture was carried out by local agronomists. It is emphasized that it was only in the early 1890s that the Tobolsk Provincial Committee attempted to systematize information on the state of agriculture in the province on the basis of data received from respondents living in rural areas and villages. The presented material reflects the main “milestones” of the development of flax growing in the Tobolsk province in agrotechnical, economic and economic aspects

Short wavelength band structure of photons in cholesteric liquid crystals

The band structure of photons in cholesteric liquid crystals (CLCs) is investigated in the shortwave approximation. The bound states or narrow resonances of photons in the CLC are formed by the extraordinary waves. The explicit expressions for the spectrum bands and the dispersion laws of photons in these bands are obtained. It is shown that these states describe photons propagating almost perpendicular to the CLC axis. The density of photon states acquires a sharp peak due to the presence of bound states. Near this peak, in the particular case of plasma permittivity, the photons posses a linear or quadratic dispersion relations in the directions perpendicular to the CLC axis depending on the sign of the anisotropy of the CLC permittivity tensor. The resonances in the CLC plate are also described.Comment: 23 pp., 4 figs, some elucidations adde

Radiation of twisted photons from charged particles moving in cholesterics

The radiation of twisted photons by charged particles traversing a cholesteric plate is studied in the framework of quantum electrodynamics in an anisotropic inhomogeneous dispersive medium. The complete set of solutions to the Maxwell equations in the cholesteric plate is constructed in the paraxial and small anisotropy approximations. The explicit expressions for the average numbers of plane-wave and twisted photons created by a charged point particle crossing the cholesteric plate are derived. The selection rules for the twisted photons radiated at the harmonic $n\in \mathbb{Z}$ are established. In the paraxial regime, the projection of the orbital angular momentum of a radiated twisted photon obeys the selection rule $l=\pm(2n+1)$. In the approximation of a small anisotropy of the permittivity tensor, the selection rule becomes $m=\pm 2n$, where $m$ is the projection of the total angular momentum of a radiated twisted photon. The sign "$\pm$" in these selection rules is related to the choice of the forward or reflected waves in the cholesteric and is realized at the different energies of radiated photons. As the examples, the radiation of optical twisted photons by electrons with the Lorentz factors $\gamma=235$ and $\gamma=500$ and by uranium nuclei with $\gamma=2$ are considered. It is shown that charged particles traversing normally a cholesteric plate can be used as a pure source of twisted photons.Comment: 23 pp., 4 figs; some misprints correcte