On the approximation of solutions of one singular differential equation on the axis

In this paper we study the problem of the best approximation by linear methods of solutions to one Triebel-type equation. This problem was solved by using estimates of the linear widths of the unit ball in corresponding spaces of differentiable functions. According to the definition, linear widths give the best estimates for the approximation of compact sets in a given normed space by linear methods which are implemented through finite-dimensional operators. The problem includes answers to the questions about the solvability of the studied equation, the construction of the corresponding weighted space of differentiable functions, the development of a method for estimating linear widths of compact sets in weighted polynomial Sobolev space. In this work, conditions are obtained under which the considered operator has a bounded inverse. The weighted Sobolev space corresponding to the posed problem is determined. Upper estimates are obtained for the counting function for a sequence of linear widths, which correspond to the posed problem. One example is constructed in which two-sided estimates of linear widths are given. The method for solving this problem can be applied to the numerical solution of non-standard ordinary differential equations on an infinite axis

Evaluation of Reservoir Inflows Using Semi-Distributed Hydrological Modeling Techniques: Application to the Esil and Moildy Rivers' Catchments in Kazakhstan

[EN] This study explores the potential application of the HBV model for simulating water inflow into the Astana reservoir in Kazakhstan. The Astana reservoir, with an area of 60.9 km2 and a capacity of 411 million m3, serves as a vital hydrotechnical structure for the regulation of long-term water resources. Positioned on the Esil River, this reservoir plays a crucial role in providing drinking water to Astana, the capital city of the Republic of Kazakhstan. This study presents a concise overview of the HBV model and includes hydrometeorological data as well as information from a digital elevation model constructed from altitude maps of the catchment areas of the Esil and Moildy rivers. To simulate the runoff from both rivers, the GAP optimization algorithm was employed. Model parameters were calibrated for the period spanning 1975 to 2020. The effectiveness of the model was evaluated using the Nash-Sutcliffe criterion, which confirms a strong correlation between the simulated runoff dynamics and observed data. This study's outcomes reveal the efficiency of the selected optimal parameters, particularly for the 2020-2022 timeframe, during which the HBV model's parameters were validated. Overall, the quality metrics achieved during both the calibration and validation periods are satisfactory, affirming the model's suitability for short-term runoff forecasts, especially during flood events. Furthermore, the model proves valuable for assessing potential shifts in river runoff patterns under the influence of climate change.Serikbay, NT.; Tillakarim, TA.; Rodrigo-Ilarri, J.; Rodrigo-Clavero, M.; Duskayev, KK. (2023). Evaluation of Reservoir Inflows Using Semi-Distributed Hydrological Modeling Techniques: Application to the Esil and Moildy Rivers' Catchments in Kazakhstan. Water. 15(16). https://doi.org/10.3390/w15162967151

Studying Fiber­reinforced Concrete for Casting Housing Parts of Pumps

Many enterprises of the mining and metallurgical industry use pumps transferring aggressive liquids and slurries containing abrasive particles. For the manufacture of pump housings, taking into account their operating conditions, expensive alloy steels with increased wall thickness are used.As a result of the study, the analysis of possible materials for the manufacture of fiber-reinforced concrete with the required strength characteristics was carried out. The selection of the optimum ratio of the components, providing, on the one hand, cost minimization of fiber-reinforced concrete and, on the other hand, rational technology for the manufacture of housing parts of fiber-reinforced concrete without additional machining, was carried out.It was found that the specified conditions are met to the greatest extent by the mixes containing crushed rubble, quartz sand and ground quartz as aggregate, anchor steel fiber, as well as resin and hardener.Theoretical and experimental studies showed that the aggregate must meet the following requirements: it must be three-component by particle size distribution, and the particle size of each component must differ by an order of magnitude from the previous one. This allows obtaining dense mixes by filling voids in large fractions with smaller particles.As a result of laboratory studies, it was found that the compressive strength of such hardened mixes is 230...240 MPa.It was found experimentally that the optimum fiber additive (steel anchor) should be within 3...5 % by weight.The results of the study allow carrying out calculations of the parameters of pump housing parts with reduced wall thickness, lower weight, and also developing a technology for casting such parts with a high degree of readiness for us

Evaluation of Reservoir Inflows Using Semi-Distributed Hydrological Modeling Techniques: Application to the Esil and Moildy Rivers’ Catchments in Kazakhstan

This study explores the potential application of the HBV model for simulating water inflow into the Astana reservoir in Kazakhstan. The Astana reservoir, with an area of 60.9 km2 and a capacity of 411 million m3, serves as a vital hydrotechnical structure for the regulation of long-term water resources. Positioned on the Esil River, this reservoir plays a crucial role in providing drinking water to Astana, the capital city of the Republic of Kazakhstan. This study presents a concise overview of the HBV model and includes hydrometeorological data as well as information from a digital elevation model constructed from altitude maps of the catchment areas of the Esil and Moildy rivers. To simulate the runoff from both rivers, the GAP optimization algorithm was employed. Model parameters were calibrated for the period spanning 1975 to 2020. The effectiveness of the model was evaluated using the Nash–Sutcliffe criterion, which confirms a strong correlation between the simulated runoff dynamics and observed data. This study’s outcomes reveal the efficiency of the selected optimal parameters, particularly for the 2020–2022 timeframe, during which the HBV model’s parameters were validated. Overall, the quality metrics achieved during both the calibration and validation periods are satisfactory, affirming the model’s suitability for short-term runoff forecasts, especially during flood events. Furthermore, the model proves valuable for assessing potential shifts in river runoff patterns under the influence of climate change

Immunochromatographic System for Serodiagnostics of Cattle Brucellosis Using Gold Nanoparticles and Signal Amplification with Quantum Dots

In this article, we describe an immunochromatographic test system developed for rapid serodiagnostics of cattle brucellosis using two markers: Gold nanoparticles (GNPs) and quantum dots (QDs). The test system was compared with immunochromatographic serodiagnostics systems that use only one marker. The approbation of the test system was conducted on samples of cattle sera with low, but diagnostically significant titers of specific antibodies. We show that when two conjugates are used, the intensity of the detectable signal increases by 2–3 times compared with the test system using the QD conjugate and by more than nine times compared with the system using the GNP conjugate

Triple Immunochromatographic System for Simultaneous Serodiagnosis of Bovine Brucellosis, Tuberculosis, and Leukemia

An immunochromatographic test system has been developed for the simultaneous rapid multiplex serodiagnostics of bovine brucellosis, tuberculosis, and leukemia. The test system is based on the use of a conjugate of gold nanoparticles with the chimeric protein Cysteine-A/G and three analytical zones with immobilized pathogen antigens: Brucella abortus lipolysaccharide, recombinant proteins MPB64 and MPB83-MPB63 of Mycobacterium bovis, and recombinant protein p24 of the bovine leukemia virus. Prototypes of the test system were tested on 98 samples of sera from healthy and infected animals. The diagnostic sensitivity of the developed test system was 92% for brucellosis, 92% for tuberculosis, and 96% for leukemia. False positive test results were not observed

A gradient of radioactive contamination in Dolon village near the SNTS and comparison of computed dose values with instrumental estimates for the 29 August, 1949 nuclear test

金沢大学環日本海域環境研究センター地球環境計測研究部門Spatial distributions of soil contamination by 137Cs (89 sampling points) and 239+240pu (76 points) near and within Dolon village were analyzed. An essential exponential decrease of contamination was found in Dolon village: the distance of a half reduction in contamination is about 0.87-1.25 km (in a northwest-southeast direction from the supposed centerline of the radioactive trace). This fact is in agreement with the available exposure rate measurements near Dolon (September 1949 archive data): on the basis of a few measurements the pattern of the trace was estimated to comprise a narrow 2 km corridor of maximum exposure rate. To compare computed external doses in air with local dose estimates by retrospective luminescence dosimetry (RLD) the gradient of radioactive soil contamination within the village was accounted for. The computed dose associated with the central axis of the trace was found to be equal to 2260 mGy (calculations based on archive exposure rate data). Local doses near the RLD sampling points (southeast of the village) were calculated to be in the range 466-780 mGy (averaged value: 645+/-70 mGy), which is comparable with RLD data (averaged value 460+/-92 mGy with range 380-618 mGy). A comparison of the computed mean dose in the settlement with dose estimates by ESR tooth enamel dosimetry makes it possible to estimate the "upper level" of the "shielding and behavior" factor in dose reduction for inhabitants of Dolon village which was found to be 0.28+/-0.068