One of the shortcomings of the classical electromagnetic method of Zavoisky is sensitivity to the non-one-dimensionality of the flow behind the wave front. In this paper, it is proposed to use ...a four-pin gauge to correct measurements. Two signals are recorded from
-shaped gauges, one of which is located in a plane tangent to the front, and the other in a plane parallel to the direction of wave propagation. Next, the two signals are combined into a true velocity signal that is insensitive to the curvature of the front. The second difficulty that arises in electromagnetic measurements is the rather large size of the gauges. Typically, the length of the working arm
is about 1 cm. An analysis of the potential distribution in the gauge shows that the proposed combined gauge is equivalent to two sensors of zero width, and the effective length
is the distance between the midlines of the leads. It is shown that the value of
can be reduced to 1.5–2 mm with a lead width of about 0.5 mm. This makes it possible to perform local measurements at spots of millimeter size and use small-size charges. These improvements bring electromagnetic measurements closer to the level of modern optical techniques while using much cheaper equipment.
Observations of giant pulses from the Crab pulsar have been carried out at frequencies of 61 and 111 MHz. The pulse profiles show a significant (nonzero) duration of the leading edge, which is ...inconsistent with the model of a single thin scattering screen. Several possible variants of the formation of scattered pulses with a nonzero duration of the leading edge have been analyzed. The case of scattering by two thin screens describes well the observed characteristics of the pulse profiles (the duration of the leading edge and the characteristic scattering time). The characteristic scattering times of two thin scattering screens have been determined:
ms and
ms at 61 MHz;
ms and
ms at 111 MHz. A monitoring of the scattering parameters is needed to determine which of the screens refers to the global interstellar medium and which refers to the local medium in (near) the Crab Nebula.
Observations of individual pulses from the pulsar PSR B1530+27 have been carried out. The dispersion measure (DM) toward this pulsar has been found from 11 084 pulses to be
pc cm
. The (
) upper ...limit on the DM derivative is
pc cm
yr
. The seasonal DM variations related to the passage of radiation through the interplanetary plasma do not exceed 0.01 pc cm
.
We study the approach problem for a control system containing an unknown constant parameter an approximate value of which is reported at the initial time moment. For a resolving program control we ...propose to take a linear interpolation on the domain of possible values of the parameter. The resolving controls are constructed as convex linear combinations of nodal program controls calculated at the nodal values of the parameter. The nodal program controls are constructed by separating controls into the main and correcting ones. We obtain an error estimate in the form of an estimate for the distance between the terminal state of the system and the target set.
Abstract
The focus areas for the Fisheries industry in Russia are increasing the share of products with high added value and development of the domestic consumer market of fishery products. In the ...Russian Federation the products made of aquatic bioresources, such as stock fish, air-dried and dried fish, are traditionally in strong demand with the population. It has been determined, that the manufacture of these fish products remains at a low level. In order to increase the volume of dried and stock fish production, improve the product’s quality specifications, it is necessary to develop the technology of the drying process, as well as to find the ways and methods to decrease the drying time. The efficiency of these productions can be increased by using the scientific-based process solutions that allow to keep the production costs down, improve the consumer properties of the end products and ensure its safety. The generalized dependences for calculating the duration of dehydration in production of air-dried and stock fish products have been developed in this study. The generalization has been performed based on the ratio of the current moisture content of fish to the first and second critical moistures of the kinetics curves of dehydration. A formula for calculating the current moisture content depending on the duration of the dehydration process and the dependence for calculating the drying time in relation to fish moisture have been introduced. The patterns received allow to model the kinetics curves of fish dehydration. A functional relation between the critical moistures of the kinetics of dehydration, the water diffusion coefficients and the initial moisture content has been determined. The derived dependencies allow to calculate the diffusion coefficients in the critical points of the kinetics curve of dehydration. The obtained formulas could be used for calculating the water diffusion coefficients in fish. Using the suggested formulas makes it possible to solve the diffuse type partial differential equation. This gives an opportunity to model the water distribution in fish during the process of dehydration.
Observations on the search for pulsed radio emission from the Geminga pulsar and the close isolated neutron star 1RX J1308.6+2127 (RBS 1223) at the frequency of 111 MHz are performed. No pulsed ...signals are detected from both sources. Upper limits for the average flux density are determined as 0.4–4 mJy for the Geminga pulsar and 1.5–15 mJy for RBS 1223 depending on the assumed duty cycle (0.05–0.5) at the frequency of 111 MHz.
The paper discuss the electrical conductivity in detonating benzotrifuroxan. The obtained data demonstrate that the primary carbon condensation takes less than several nanoseconds time.
Sarcoidosis as an Autoimmune Disease Starshinova, Anna A; Malkova, Anna M; Basantsova, Natalia Y ...
Frontiers in immunology,
01/2020, Letnik:
10
Journal Article
Recenzirano
Odprti dostop
Despite the large number of performed studies, the etiology and pathogenesis of sarcoidosis still remain unknown. Most researchers allude to the possible autoimmune or immune-mediated genesis of the ...disease. This review attempts an integral analysis of currently available information suggesting an autoimmune genesis of sarcoidosis and is divided into four categories: the evaluation of clinical signs described both in patients with sarcoidosis and "classic" autoimmune diseases, the role of triggering factors in the development of sarcoidosis, the presence of immunogenic susceptibility in the development of the disease, and the analysis of cellular and humoral immune responses in sarcoidosis. Studying the etiology and pathogenesis of sarcoidosis will improve diagnostic procedures as well as the prognosis and patients' quality of life.
A new super resolution imaging technique which potentially enables sub-µm spatial resolution, using a detector of pixels much larger than the spatial resolution, is proposed. The method utilizes ...sample scanning through a large number of identical X-ray microprobes periodically spaced (the period corresponds to a multiple of the pixel size), which reduces drastically the scanning time. The information about the sample illuminated by the microprobes is stored by large detector pixels. Using these data and sample position information, a super-resolution image reconstruction is performed. With a one-dimensional (1D) high aspect ratio nickel single lens array designed for theoretically expected sub-µm microprobes at 17 keV and fabricated by deep X-ray lithography and electroforming technique, 2 µm X-ray microprobes with a period of 10 µm were achieved. We performed a first experiment at KARA synchrotron facility, and it was demonstrated that the smallest structure of a test pattern with a size of 1.5 µm could be easily resolved by using images generated from a detector having a pixel size of 10.4 µm. This new approach has a great potential for providing a new microscopic imaging modality with a large field of view and short scan time.
In 2014, S. R. Nasyrov asked whether it is true that simple partial fractions (logarithmic derivatives of complex polynomials) with poles on the unit circle are dense in the complex space
. In 2019, ...M. A. Komarov answered this question in the negative. The present paper contains a simple solution of Nasyrov’s problem different from Komarov’s one. Results related to the following generalizing questions are obtained: (a) of the density of simple partial fractions with poles on the unit circle in weighted Lebesgue spaces on
; (b) of the density in
of simple partial fractions with poles on the boundary of a given domain for which
is an inner chord.
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