8 research outputs found

    The Kuramoto-Sivashinsky equation for adatoms interacting through quasi-Rayleigh waves and formation of ordered adatom structures

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    It is shown that the defect-deformational (DD) cooperative nucleation of ordered ensembles of nanoparticles on isotropic surfaces of solids with the participation of quasi-Rayleigh waves can be described by a closed two-dimensional nonlinear DD equation of the Kuramoto-Sivashinsry (KS) type. A solution to the linearized DDKS equation describes the threshold appearance of the periodic surface strain modulation accompanied by the simultaneous formation of adatom (surface defect) piles at extrema of the surface strain. Numerical solutions to the DDKS equation in linear and nonlinear regimes describe the formation of three types of surface structures of adatom piles (clusters): lamellar-like structures, cellular disordered and hexagonal ordered ones. In the well-developed nonlinear regime, generated ensembles of nanoparticles become trimodal regarding their size distribution due to the generation of the second harmonics, degenerate parametric decay and summation of wavevectors of DD gratings taking part in the DD selforganization. The selforganizing periodic cellular DD surface structure can serve as a selforganized template for the subsequent growth of nanoparticles in the processes of atoms deposition

    Survivability of the locomotive cabin at interval estimation of obstacle parameters

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    The article considers the multiparameter problem of the mechanical system behavior and its survivability when destructing individual elements. The technique for constructing the area of safe operation of the cabin of the GT1-h gas turbine locomotive was illustrated on the example of collision of a locomotive with an obstacle at a crossing. The main parameters determining the energy of interaction between the cabin and the obstacle was singled out, and their influence on the survivability of the structure was analyzed. The finite element method was used to calculate the load-bearing capacity of a power frame with a buffer device in the initial state and after the destruction of individual structural elements by the dynamic strength criterion. The force of elastic interaction between the locomotive and the obstacle was estimated through the spring, the rigidity of which was estimated on the basis of the finite element calculation results. As a result of the calculations, proposals were developed to strengthen the cabin frame to ensure the safety of the crew and the instrument part in case of unauthorized collision with an obstacle of considerable mass and violation of the speed regime

    Survivability of the locomotive cabin at interval estimation of obstacle parameters

    No full text
    The article considers the multiparameter problem of the mechanical system behavior and its survivability when destructing individual elements. The technique for constructing the area of safe operation of the cabin of the GT1-h gas turbine locomotive was illustrated on the example of collision of a locomotive with an obstacle at a crossing. The main parameters determining the energy of interaction between the cabin and the obstacle was singled out, and their influence on the survivability of the structure was analyzed. The finite element method was used to calculate the load-bearing capacity of a power frame with a buffer device in the initial state and after the destruction of individual structural elements by the dynamic strength criterion. The force of elastic interaction between the locomotive and the obstacle was estimated through the spring, the rigidity of which was estimated on the basis of the finite element calculation results. As a result of the calculations, proposals were developed to strengthen the cabin frame to ensure the safety of the crew and the instrument part in case of unauthorized collision with an obstacle of considerable mass and violation of the speed regime

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    Light induced metallization in laser-deposited galliun films

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    Light-induced metallization was studied in laser-deposited gallium films. It was found that mirrors prepared upon silica glass by ultrafast pulsed laser deposition of elemental gallium shows a highly reproducible and fully reversible light-induced reflectivity increase. The effect was explained as being due to nonthermal light-induced metallization of gallium at the interface

    Using labview software to collect and process measurement data as partof development of systems of monitoring of bearing structures ΠŸΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ labview для Ρ€Π΅ΡˆΠ΅Π½ΠΈΡ Π·Π°Π΄Π°Ρ‡ сбораи ΠΎΠ±Ρ€Π°Π±ΠΎΡ‚ΠΊΠΈ Π΄Π°Π½Π½Ρ‹Ρ… ΠΈΠ·ΠΌΠ΅Ρ€Π΅Π½ΠΈΠΉ ΠΏΡ€ΠΈ разработкСсистСм ΠΌΠΎΠ½ΠΈΡ‚ΠΎΡ€ΠΈΠ½Π³Π° нСсущих конструкций

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    Present-day urban construction trends make buildings taller and the urban environment denser. These developments result in the growth of negative effects produced on existing structures. That’s why the monitoring of the technical condition of structures is of vital importance. Now the most efficient way of forecasting and preventing emergency situations consists in the installation of automated monitoring systems operating in continuous and periodic modes.Monitoring systems may comprise various sensors, devices and measurement elements. Any signal must be coordinated to make sure that the data are accurate and reliable. Moreover, the proposed system (or network) composed of various items of equipment (often produced by various manufacturers) demands appropriate integrated software. The database of LabVIEW drivers can be employed for this purpose.LabVIEW environment is applied for the measurement, testing and management of applications that constitute embedded programming tools needed to develop complex applications designated for computer-aided measurements and data processing. The library of drivers is employed to assure the availability of the most common types of interfaces, sensors and devices. If a user lacks a particular driver, it can be either integrated or developed. The authors have successfully collected and processed the data in the LabVIEW environment of a measurement system based on tensometric sensors attached to experimental items of equipment.Обоснована Π½Π΅ΠΎΠ±Ρ…ΠΎΠ΄ΠΈΠΌΠΎΡΡ‚ΡŒ провСдСния автоматичСского ΠΌΠΎΠ½ΠΈΡ‚ΠΎΡ€ΠΈΠ½Π³Π° нСсущих конструкций, рассмотрСн Π°Π»Π³ΠΎΡ€ΠΈΡ‚ΠΌ сбора Π΄Π°Π½Π½Ρ‹Ρ…, прСдставлСны Π½Π°ΠΈΠ±ΠΎΠ»Π΅Π΅ распространСнныС Ρ‚ΠΈΠΏΡ‹ ΠΏΡ€Π΅ΠΎΠ±Ρ€Π°Π·ΠΎΠ²Π°Ρ‚Π΅Π»Π΅ΠΉ. Обосновано ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ срСды LabVIEW ΠΈ ΠΏΡ€ΠΈΠ²Π΅Π΄Π΅Π½Π° Π±Π»ΠΎΠΊ-Π΄ΠΈΠ°Π³Ρ€Π°ΠΌΠΌΠ°, написанная Π² срСдС LabVIEW, для сбора, ΠΎΠ±Ρ€Π°Π±ΠΎΡ‚ΠΊΠΈ ΠΈ записи ΠΈΠ·ΠΌΠ΅Ρ€ΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎΠΉ ΠΈΠ½Ρ„ΠΎΡ€ΠΌΠ°Ρ†ΠΈΠΈ
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