This study proposes an integrated design approach for a multifunctional UAV using composite materials, combining vacuum infusion, CFD-based aerodynamic analysis, and an STM32-based energy management system. CFD results showed a lift coefficient C L = 0.812, drag coefficient C D = 0.055, and L / D = 14.7, representing a 28 % improvement over aluminum structures. FEM analysis indicated a maximum stress of 312.4 MPa with a safety factor of 1.12, while vacuum infusion achieved 98.7 % resin impregnation, enhancing stiffness by 28 % and reducing weight by 25 %. The automated energy management system increased energy efficiency by 16.3 %, extending flight duration and improving operational stability.

The transport of material by vibratory conveyors involves micro-throws of particles, which can be undesirable for certain materials. This study investigates body motion in a conveyor trough whose bottom executes harmonic oscillations perpendicular to the transport direction, while the side walls undergo asymmetric oscillations. The methodology combines mathematical modelling and laboratory experiments. Numerical integration of the governing differential equations using a fourth-order Runge-Kutta scheme yielded the body displacement over one oscillation period, which enabled estimation of the average conveying speed and, consequently, the throughput. The study substantiates the concept and demonstrates the feasibility of the proposed vibratory-conveyor architecture. The results can inform the design of conveyors with throughput regulated by adjusting oscillation frequency or amplitude.

Analysis of dynamic characteristic was conducted focusing on the transportation of high-pressure storage tanks, covering two scenarios: independent transportation and mixed transportation. For independent transportation, analysis of free modal was carried out to obtain the first four orders of modal shapes. Additionally, the influence of two constraint methods on the modal characteristics and stress distribution was studied, including fixed at both ends and fixed at the cylinder body. Results show that when the tank was fixed at the cylinder body, it had a higher natural frequency and a lower stress level, making it safer. For mixed transportation, a finite element model was built for 6 high-pressure storage tanks, and analysis of random vibration was performed. The results showed that stress was mainly concentrated on the crossbeams and connection nodes, while the stress on the main body of the storage tanks was relatively low. The overall structure exhibited excellent fatigue performance and met the mechanical and safety requirements under random vibration conditions.

This study investigates the influence of thermally activated sparingly soluble additives – phosphogypsum, limestone, and fly ash – on the rheological behavior and strength characteristics of Portland cement. Additives were incorporated in amounts of 1-5 % into clinkers from the Kuvasoy and Bekabad plants and evaluated for workability, water-cement ratio, and compressive strength. The results demonstrate that thermal activation (200-400 °C) enhances the surface reactivity of additives, promoting accelerated hydration of calcium silicates and improved microstructural densification. Compressive strength reached 534×10 5 Pa at 28 days for mixtures containing 5 % limestone activated at 200 °C. These improvements are particularly relevant for vibration-resistant transport structures – such as bridge decks, pavements, and railways – where enhanced flowability and durability are essential. The research also supports sustainable cement production through the valorization of industrial by-products like phosphogypsum and fly ash.

The purpose of this study is to analyze the prospects for transitioning the city from automobile-dominated mobility to a public transport-oriented system. The methodological framework is based on the analysis of transport infrastructure. The research is conducted on the example of Tashkent – the capital of Uzbekistan – characterized by a high level of motorization and significant commuter migration. The study concludes that a successful transition to public transport requires a phased implementation, involving infrastructure modernization, digitalization, regulation of motorization, and transformation of citizens’ mobility behavior. The novelty of this study lies in developing a digital transition model for Tashkent that integrates international best practices (Berlin, London, Singapore) with the local transport and socio-economic conditions.

The study evaluates the efficiency of a natural diatomite-based sorbent, Diamiks Aqua, for removing petroleum hydrocarbons and suspended solids from railway wastewater. Laboratory tests using a vertical filtration column (0.5 m/h, 30 min contact time) demonstrated up to 98.9 % removal of suspended solids and 99.0 % of petroleum products. A three-layer filtration strip, integrated into railway embankments, provides a reagent-free and energy-efficient treatment process. The proposed design ensures reliable protection of water bodies from diffuse hydrocarbon runoff and contributes to the environmental sustainability of railway transport enterprises.

The dynamics of nonlinear viscoelastic plates and shells is a crucial area of study in modern mechanics, materials science, and engineering. This importance stems from the increasing demand for accurate modeling and analysis of structures subjected to complex loads, as well as the advancement of new materials and technologies. Modern materials, including carbon composites, polymers, and multilayer coatings, possess complex viscoelastic properties. Under dynamic loads, such as vibrations or impacts, viscoelastic materials exhibit time-dependent responses to these loads, necessitating careful consideration of their relaxation and creep characteristics. The unique viscoelastic properties allow these materials to adapt to applied loads, making them highly desirable for the design of sophisticated devices, such as sensors, membranes, and adaptive structures. Furthermore, interactions with external fields – such as electromagnetic or thermal forces – enhance the effects of nonlinearities and require the development of new modeling approaches. The paper presents the equations of dynamics of geometrically and physically nonlinear thin-walled elements. An operator approach based on Rabotnov’s hereditary kernels is proposed, which makes it possible to correctly account for relaxation processes. The novelty of the work lies in the consideration of the combined effect of geometric and physical nonlinearities. To demonstrate the applicability of the model, a numerical example of the deflection of a rectangular plate under uniform loading is examined. Graphs of the deflection evolution and the influence of thickness and relaxation parameters are presented.

The sustained growth of traffic intensity and axle loads in Uzbekistan has accelerated the deterioration of in-service road bridges, making cost-effective strengthening a national priority. This paper presents a structured review and comparative assessment of strengthening approaches grouped into: (i) traditional cross-section enlargement and substructure rehabilitation, (ii) structural scheme optimization and dead-load reduction (including external prestressing and span continuity), and (iii) advanced solutions based on carbon-fiber-reinforced polymers (CFRP). A worked example for a typical reinforced-concrete girder span demonstrates the compensation of a deficient bending moment of Δ M = 70 kN·m and indicates an ~18-25 % increase in load-carrying capacity after strengthening. The paper further synthesizes implementation considerations for arid-continental climates, including surface preparation, adhesion control, protective coatings, and staged load testing. Drawing on regional practice, CFRP systems are highlighted as offering high strength-to-weight benefits, installation speed, and minimal traffic disruption; reported gains for flexural elements typically range from 25 % to 45 %, subject to detailing and quality assurance. The results support integrating CFRP-based measures and complementary dead-load optimization into bridge rehabilitation programs in Uzbekistan, with recommendations for monitoring intervals (6-12 months) and future durability studies on adhesives and UV/moisture protection. Overall, the study consolidates methods and provides quantitatively grounded guidance for extending service life under contemporary traffic demands.

In this study, a technology for producing high-strength spheroidal graphite cast iron of grade VCh50 using secondary steel scrap in an induction crucible furnace was developed. During the research, the efficiency of using complex modifiers in the ladle and mold gating system was investigated. The influence of elements such as magnesium, calcium, aluminum, barium, cerium, and lanthanum contained in these modifiers on the graphite morphology, structure, and mechanical properties of the molten cast iron was analyzed.

The article presents the types of belt transmission designs, as well as the advantages of their use in mechanical engineering. Belt drives create loads as a result of excessive vibrations due to a flexible element (belt). A new design of an innovative toothed belt drive is proposed, which contains two paired driving and driven gear pulleys with different diameters and two belts with teeth covering them, while the gear ratios of each pair of gears are equal to each other. The simulation demonstrates a 25-38 % reduction in velocity fluctuation compared to conventional drives, confirming the effectiveness of the proposed design.