Search

See the retraction notice BIO Web of Conferences 84, 00001 (2024), https://doi.org/10.1051/bioconf/20248400001

See the retraction notice BIO Web of Conferences 84, 00001 (2024), https://doi.org/10.1051/bioconf/20248400001

In article discusses models of unlimited track circuits with a receiver, adapting to different working conditions, applied double receiver with one power supply in the middle, which allows you to extend the length of the continuous rail circuit. For this, a goal is set, in which is the development of models of jointless track circuits with an adaptive receiver, in which the rail line must take into account the total stress distribution along the rail line and disturbing factors. The article presents the equivalent circuits of continuous welded rail circuits with an adaptive receiver, algorithmic expressions for determining currents and voltages at the ends of the rail circuit, the coefficients of rail lines with an adaptive receiver are developed, calculation algorithms are presented. In conclusion, a graph is given, according to which it is shown that a continuous rail circuit with an adaptive receiver can operate with an insulation resistance three times lower than the threshold value in any modes of the rail circuit, taking into account the fact that, minimum allowable insulation resistance for tone-on-tone continuous rail circuits is taken as Ri=0,7ohm*km. Derived for the theory and synthesis of solutions, and also proposed new approaches to ensure the operating modes of the rail circuit, taking into account the real and weather conditions of operation.

See the retraction notice E3S Web of Conferences 549, 00001 (2024), https://doi.org/10.1051/e3sconf/202454900001

See the retraction notice E3S Web of Conferences 549, 00001 (2024), https://doi.org/10.1051/e3sconf/202454900001

One of the drawbacks of the currently used tonal rail chains without insulating joints is that when the train approaches the controlled section, the train begins to shunt this section at some distance before entry on him. In connection with the traffic light moves on this distance. But being that this distance depends on many variables, it constantly changes these variables. For eliminate this drawback, instead of the traditional potential receiver it is proposed to use electric current track receiver, which has a clear boundary fixation entry of train on the controlled section. By now developed and used methods for determining the main analytical expressions for analysis and synthesis tonal rail circuits with potential receivers in various operating modes, and the theoretical issues of tonal rail chains with current receivers were practically not considered, in this connection, the article considers the development of mathematical models for determining the absolute shunt sensitivity of tonal rail chains without isolating joints with current receivers and methods for calculating determination of the critical location of the minimum shunt sensitivity.

The normal operating state of jointless and butt track circuits depends on the state of change in the insulation resistance; respectively, the correct choice of the maximum and minimum limit resistance characteristics should be considered. The maximum and minimum limit resistance depends on the power consumption of the unlimited track circuit in the normal and the mode of movement of the wheelset at the supply end of the rail line. The article presents a study of an intelligent track circuit without insulated joints, where logical elements replace all the equipment of mechanical and electrical energy converters. The research aims to determine the shunt that affects the definition of the movable block, respectively, the definition of the power of the shunt. The method consists in choosing a sensor, namely an intelligent track control sensor, and developing a mathematical model for determining the shunt power, which provides the influence of the shunt on the track circuit. Research carried out for track circuits with insulating joints has shown that with the value of the argument, modulus, and synthesis of the maximum-minimum limit resistance when the supply end is shunted, the maximum power will be the least minimum Rkmax. Because of the lack of more accurate data for an intelligent control sensor, studies were carried out.

While Wi-Fi 5 is still sufficient for many organizations and businesses, it is important to consider and upgrade to Wi-Fi 6. This article discusses the main differences between Wi-Fi 5 and Wi-Fi 6. The goal is to identify key metrics transmission of information content of signals, a method for determining the best use of Wi-Fi signals for certain categories of use, an analysis and study of the influence of frequencies on the quality of transmitted information, and also analyzes the growth rate of an organization using these technologies. Using the Orthogonal Frequency Division Multiple Access connection principle, Wi-Fi 6 technology provides the main advantage of performing multiple receptions and transmissions at the same time. Multiple User Multiple Input Multiple Output technology allows routers to communicate with all devices at the same time, resulting in maximum packet exchange. Using the Basic Service Set (BSS) color scheme, we can see that Wi-Fi 6 is far ahead of previous technologies.

The article analyzes the operation of relative track circuits, which shows that they are able to provide reliable control of the state of the rail line in extreme climatic conditions. Reliable operation of relative track circuits can be carried out at very low values of insulation resistance, down to 0.1 Ohm km and below. The method of monitoring the state of the rail line, based on fixing the voltage of the receiving end before the train approaches and then determining the threshold values, significantly expands the range of changes in the insulation resistance, in which the normal operation of the track circuit is possible. The goal is to represent the track circuit, where the theory of the rail line is used according to the standard of the track circuit operating modes, at present many factors have not been taken into account for high-speed traffic, one of these is the transmission resistance with insulation resistance, the influence of disturbing and other factors. Mathematical modeling has been developed to determine the insulation resistance in various weather conditions.

See the retraction notice E3S Web of Conferences 420, 00001 (2023), https://doi.org/10.1051/e3sconf/202342000001

See the retraction notice E3S Web of Conferences 420, 00001 (2023), https://doi.org/10.1051/e3sconf/202342000001

See the retraction notice E3S Web of Conferences 420, 00001 (2023), https://doi.org/10.1051/e3sconf/202342000001

The design of the suspension unit of the flame tube in the housing of the annular combustion chamber of a ground-based gas turbine installation of a gas pumping unit is given for placing it in a device for fixing the flame tube in the combustion chamber housing, where automatic clearance selection is required arising between the contacting surfaces of the docking nodes of the combustion chamber and the nozzle apparatus of the turbine, when the combustion chamber is operating as part of the engine. The proposed design of the suspension unit of the flame tube in the annular combustion chamber housing makes it possible to increase the reliability and resource of the combustion chamber and, in general, the entire ground-based gas turbine installation by eliminating the jamming of the split rings in the cups of the suspension units and the misalignment of the pushers relative to the suspension units and split support rings.

The method is based on the analysis of the stress-strain state of the free (power) turbine (FT) disk and its change during long-term operation in accordance with the characteristics of the operation of a ground-based gas turbine engines (GTE) for gas pumping aggregate (GPA). In addition, the paper examines statistical data on the mechanical characteristics and durability of the material disk of a FT — a heat-resistant nickel-based alloy EI698-VD. It takes into account the change in the characteristics of the material during the long-term operation of the ground-based GTE for GPA. The durability of the FT disk is predicted based on changes in statistical strength reserves during operation. The object of the study is the FT disk of the NK-16ST, which is currently widely used and has an established assigned resource of 150,000 hours.

Various principles can be used to implement intelligent track circuits: voltage regulation of the power supply, compensation methods for switching on rail lines and track circuit devices, receiver sensitivity adjustment, comparison of two electrical parameters of one, two, or more track circuits, as well as a combination of these methods. At present, such improvement of track circuits is becoming relevant, which would make it possible to exclude from the circuits one of the most unreliable elements - an insulating joint, use a modern microprocessor element base in devices for monitoring the state of track sections, thus ensure their reliable operation. This will significantly reduce the costs of building and operating interval control systems and increase train traffic safety. These requirements are met by intelligent track circuits, which consider the current value of the insulation resistance, the rate of change of this resistance, and the longitudinal asymmetry.

Reactions on nat Zr induced by alpha-particles with energies up to 60 MeV were studied by stacked foils method. Production cross-sections for zirconium ( 88,89,95 Zr), niobium ( 90,92m,95m,95,96 Nb) and molybdenum ( 90,93m,99 Mo) radionuclides were determined and thick target yields were calculated. The possibility of obtaining 90 Nb through the intermediate formation of 90 Mo is discussed. It is possible to obtain 19.6 MBq/(μA·h) 90 Mo upon saturation, that leads to 4 MBq/(μA·h) 90 Nb after decay., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Introduction: Four terbium isotopes 149,152,155,161 Tb emitting various types of radiation can be used for both diagnostics and therapy. 152 Tb emits positrons and is ideal for PET. 155 Tb is considered a promising Auger emitter and a diagnostic pair for other terbium therapeutic isotopes. Several methods for the production of 155 Tb using charged particle accelerators have been proposed, but they all have significant limitations. The restricted availability of this isotope hinders its medical applications. We have proposed a new method for production of 155 Tb, irradiating enriched 155 Gd by alpha particles. The possibility of simultaneous production of two isotopes of terbium, 152,155 Tb, was also studied for more efficient cyclotron beam use., Methods: Irradiation of 155 Gd enriched targets and 155 Gd /  151 Eu tandem target with alpha-particles with an energy of 54 MeV was carried out at the U-150 cyclotron at the NRC "Kurchatov Institute". The cross sections of nuclear reactions on enr-155 Gd were measured by the stack foil technique, detecting the gamma-radiation of the activation products. The separation of rare earth elements was performed by extraction chromatography with the LN Resin. 155 Tb was produced via 155 Dy decay., Results: The cross sections for the 155,156 Tb and 155,157 Dy production were measured by the irradiation of a gadolinium target enriched with the 155 Gd isotope with alpha-particles in an energy range of 54 → 33 MeV. The yield of 155 Dy on a thick target at 54 MeV was 130 MBq/μAh, which makes it possible to obtain 1 GBq of 155 Tb in 11 hour-irradiation with 20 μA beam current. The possibility of simultaneous production of 152,155 Tb by irradiation of 155 Gd and 151 Eu tandem target with medium-energy alpha-particles is implemented. Optimal irradiation energy ranges of alpha -particles as 54 → 42 MeV for 155 Tb and 42 → 34 MeV for 152 Tb were suggested. Product activity and radionuclidic purity were calculated., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The production possibility of 161 Tb and 155 Tb by irradiating of natural dysprosium with gamma rays obtained by decelerating an electron beam with an energy of 55 MeV has been demonstrated experimentally. The yield of 161 Tb was 14.4 × 10 3 Bq × μA -1  × h -1  × cm 2 × g Dy2O3 -1 . Simultaneously, upon irradiation, 155 Dy is formed with the yield of 25 × 10 3 Bq × μA -1  × h -1  × cm 2 × g Dy2O3 -1 , which leads to the formation of 1.6 × 10 3 Bq × μA -1  × h -1  × cm 2 × g Dy2O3 -1 of 155 Tb. It has been shown that the isolation of terbium radioisotopes from tens of mg of dysprosium target can be achieved by extraction chromatography, and final separation yield was 39%. The impurity of 160 Tb is 7.3% of the 161 Tb activity at EOB., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Introduction: 155 Tb (T 1/2  = 5.32 d) is considered both as a promising Auger electron emitter and as a diagnostic pair for other therapeutic terbium radionuclides. Despite several methods for its production proposed, it remains scarcely available. Most of the methods using low-energy protons and deuterons beams result in a high content of radionuclidic impurities. High purity 155 Tb can be obtained using high-energy proton beams combined with online mass separation of products, but the method remains inaccessible to most potential consumers. We have proposed an indirect method for the production of 155 Tb via formation of 155 Dy (T 1/2  = 9.9 h), which can be implemented using medium energy alpha particles beam., Methods: Gadolinium oxide targets of natural isotopic composition were irradiated by 60 MeV alpha particles beam on a U-150 cyclotron of the National Research Center "Kurchatov Institute". The cross sections of nuclear reactions were measured by the stack foil technique, detecting the gamma radiation of the activation products. Gd, Tb, and Dy were separated by extraction chromatography using the LN Resin sorbent in nitric media. The isolated dysprosium fraction was stored for a day, and the formed 155 Tb was isolated by the same method., Results: The cross sections for the formation of 159 Gd, 153-156 Tb, and 155,157 Dy under irradiation by alpha particles of a gadolinium target of natural isotopic composition in the energy range 20-60 MeV have been measured. The 155 Dy yield on a thick target at 60 MeV was 35 MBq/μAh, which makes it possible to obtain 1 GBq 155 Tb as a result of 12-hour irradiation with a beam current of 50 μA. Extraction chromatography on LN Resin sorbent in nitric enabled quick and efficient separation of Gd, Tb, and Dy. The radiochemical yield of Dy was 95%, for Tb > 95%. The main radionuclidic impurity is 153 Tb (T 1/2  = 2.34 d; <5.4% of 155 Tb activity)., Conclusions: The developed method allows the production of therapeutic amounts of 155 Tb with acceptable radionuclidic purity without the need for isotopically enriched materials. The amount of 155 Tb is sufficient for its use in Auger therapy, as well as for preclinical studies of the suitability of SPECT preparations in laboratory animals. Nevertheless, to obtain higher activities, a longer irradiation time and a higher projectile current are proposed. The 153 Tb radionuclide present in the final preparation has a shorter half-life than the target radionuclide, and its hard γ-lines have a probability of emission of less than 1%, from which it can be concluded that the negative effect will not be significant. However, a product of this purity and type of contamination requires additional testing for toxicity in living organisms. The final sample also includes a certain amount of 157 Tb (T 1/2  = 71 a, the only γ-line 54.5 keV Iγ = 0.0084%), which will complicate the labeling conditions. Thus, more research is needed in the labeling area. It should be noted that the use of gadolinium enriched in the 155 Gd or 156 Gd nuclide as a target will help not only reduce the amount of impurities but also increase the yield of 155 Tb., Competing Interests: Declaration of competing interest The authors have no competing interests to declare., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The cross sections for nuclear reactions nat Er(α,x) were measured in the energy range 60 → 10 MeV using the stacked-foil technique. The experiments were carried out in a wider energy range in comparison with previous works. The results are consistent with other studies and modeling using TENDL-2019. The 167 Tm yield was 5.4 MBq/μAh in the range 60 → 30 MeV, and the main long-lived impurity is 168 Tm (0.78% in terms of activity). The 165 Tm yield is 4.6 MBq/μAh (60 → 40 MeV). 169 Yb is formed with a yield of 1.0 MBq/μAh in the energy range 60 → 20 MeV., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Method for production of alpha emitter 149 Tb by irradiation of 151 Eu with 70 MeV 3 He nuclei is proposed. For the first time, the cross sections for the formation of isotopes 149,150,151,152 Tb were measured experimentally using a stack foil technique in the 3 He particles energy range 70 → 12 MeV. The thick target yield of 149 Tb is 39 MBq/μAh, or 230 MBq/μA 149 Tb at saturation. The optimal energy range from the point of view of radioisotopic purity is 70 → 40 MeV. At these conditions about 150 MBq/μA 149 Tb can be produced in 8 hours irradiation, which is sufficient for therapeutic applications. The main impurities are 150 Tb (~100% in activity) and 151 Tb (~30% in activity). The proposed method surpasses its counterparts by the high content of the target isotope in the natural mixture and the simplicity of the radiochemical separation of 149 Tb from the bulk target material.

Decision making, reasoning, and analysis in real-world problems are complicated by imperfect information. Real-world imperfect information is mainly characterized by two features. In view of this, Professor Zadeh suggested the concept of a Z-number as an ordered pair Z = (A, B) of fuzzy numbers A and B, the first of which is a linguistic value of a variable of interest, and the second one is a linguistic value of probability measure of the first one, playing a role of its reliability. The concept of distance is one of the important concepts for handling imperfect information in decision making and reasoning. In this paper, we, for the first time, apply the concept of distance of Z-numbers to the approximate reasoning with Z-number based IF-THEN rules. We provide an example on solving problem related to psychological issues naturally characterized by imperfect information, which shows applicability and validity of the suggested approach.

The present paper is devoted to selection of an optimal treatment method for acute periodontitis by using fuzzy Choquet integral-based approach. We consider application of different treatment methods depending on development stages and symptoms of the disease. The effectiveness of application of different treatment methods in each stage of the disease is linguistically evaluated by a dentist. The stages of the disease are also linguistically described by a dentist. Dentist's linguistic evaluations are represented by fuzzy sets. The total effectiveness of the each considered treatment method is calculated by using fuzzy Choquet integral with fuzzy number-valued integrand and fuzzy number-valued fuzzy measure. The most effective treatment method is determined by using fuzzy ranking method.

Stability is one of the fundamental concepts of complex dynamical systems including physical, economical, socioeconomical, and technical systems. In classical terms, the notion of stability inherently associates with any dynamical system and determines whether a system under consideration reaches equilibrium after being exposed to disturbances. Predominantly, this concept comes with a binary (Boolean) quantification (viz., we either quantify that systems are stable or not stable). While in some cases, this definition is well justifiable, with the growing complexity and diversity of systems one could seriously question the Boolean nature of the definition and its underlying semantics. This becomes predominantly visible in human-oriented quantification of stability in which we commonly encounter statements quantifying stability through some linguistic terms such as, e.g., absolutely unstable, highly unstable, ..., absolutely stable, and alike. To formulate human-oriented definitions of stability, we may resort ourselves to the use of a so-called Precisiated Natural Language, which comes as a subset of natural language and one of whose functions is redefining existing concepts, such as stability, optimality, and alike. Being prompted by the discrepancy of the definition of stability and the Boolean character of the concept itself, in this paper, we introduce and develop a Generalized Theory of Stability (GTS) for analysis of complex dynamical systems described by fuzzy differential equations. Different human-centric definitions of stability of dynamical systems are introduced. We also discuss and contrast several fundamental concepts of fuzzy stability, namely, fuzzy stability of systems, binary stability of fuzzy system, and binary stability of systems by showing that all of them arise as special cases of the proposed GTS. The introduced definitions offer an important ability to quantify the concept of stability using some continuous quantification (that is through the use of degrees of stability). In this manner, we radically depart from the previous binary character of the definition. We establish some criteria concerning generalized stability for a wide class of continuous dynamical systems. Next, we present a series of illustrative examples which demonstrate the essence of the concept, and at the same time, stress that the existing Boolean techniques are not capable of capturing the essence of linguistic stability. We also apply the obtained results to investigate the stability of an economical system and show its usefulness in the design of nonlinear fuzzy control systems given some predefined degree of stability.

The hair of man is one of the complicated objects of investigation in forensic medicine expertise. The purpose of this research was to determine the significance of specific gravity of grey, pigmented, thin and thick hairs from head in identification of personality. The specific gravity and diameter of 10 grey, 10 pigmented and 10 thick and 10 thin hairs were investigated in seven men. The diameter of the hair plays a significant role in determination of the body area from which the hair may have arisen. The obtained data were statistically analyzed. The specific gravity fluctuations of grey hair in each of investigated persons was: 0,58-0,65; 1,81-1,92; 1,26-1,33; 0,86-0,92; 1,56-1,66; 2,25-2,34; 2,00-2,08 10(4) H/m(3). The specific gravity fluctuations of pigmented hair in each of seven persons was: 0,57-0,64; 1,80-1,92; 1,27-1,37; 0,87-0,93; 1,57-1,66; 2,26-2,34; 1,99-2,08 10(4) H/m(3). It was concluded that establishment of specific gravity of grey and pigmented hairs from head is vital for forensic medicine.

The abundance of actinomycetes isolated from the soils of Mongolian desert steppes varies from several thousand to hundreds of thousands of CFU/g soil, depending on soil type and isolation medium. Eight actinomycete genera have been found in these soils: Streptomyces, Micromonospora, Saccharopolyspora, Actinomadura, Microtetraspora, Thermomonospora, Nocardia, and Dactylosporangium. The streptomycete complexes of brown desert-steppe and gray-brown desert alkaline soils include halophilic, alkaliphilic, and haloalkaliphilic species that grow most successfully on the media with a salt concentration of 5% and pH 8-9.

The parameters of stretching vibrations nu(OH) (frequencies and integral intensities) have been calculated from IR spectra of a large number of H-complexes of 1,1-diphenylethanol [(C(6)H(5))(2)C(CH(3))OH] with solvents of various proton accepting strength which were not regularly reported. The data has been used to estimate the formation enthalpies of H-complexes and the proton-donor action of the mentioned alcohol. Also, correlations between those spectral characteristics have been investigated. The H-bonds in 1,1-diphenylethanol (DPE) have been investigated depending on concentrations in CCl(4) and temperature by means of infrared (IR) absorption spectra measurements. It has been found that the hydrogen bonds of the crystalline DPE are formed in the manner of cyclic tetramer, while in solutions with the concentration 0.5 mol/l, cyclic dimers are formed, which in higher concentrations change into cyclic tetramers.

A procedure for determination of 237Np, 238Pu, 239,240Pu and 241Pu in environmental samples is described. Neptunium-237 is determined using radiochemical neutron activation analysis with pre- and post-irradiation chemistry based on solvent extraction and extraction chromatography. 238Pu, 239,240Pu is determined using alpha spectrometry and 241Pu by liquid scintillation spectrometry. The vertical profiles of 237Np, 238Pu, 239,240Pu in bottom sediments from the Black Sea are presented.

Analyzes the experience gained in cooperative studies aimed at the development and introduction of automated data processing systems, carried out by the Institute of Informatics, Russian Academy of Sciences, and the Krasnodar Territorial Foundation for Obligatory Medical Insurance and its branches.