The paper presents methods for obtaining qualitative metallic surfaces by electric arc welding deposition while using consumable electrode in a protective gas medium and executing regularized drop transfer of electrode metal. The drop transfer efficiency of electrode metal and productivity of welding deposition are significantly increased due to excitation of lateral vibrations in the consumable electrode with preset amplitude. The paper describes a method and a device for welding deposition of metallic surfaces by vibrating  electrode where vibrations are excited by ultrasound.

The paper contains some proposals pertaining  to modernization of tracked vehicle running gears, bogie hydro-pneumatic suspension, methodology  for bench-tests and description of test-bench equipment which is applied for testing bogie hydro-pneumatic suspension. Test results of a hydro-pneumatic spring with parameter stabilization system are given in the paper.

The paper presents  description of tracked vehicle running gears with bogie hydro-pneumatic suspension which is equipped with a system for stabilizing a road clearance. Testing results of the gears being part of a test mule are cited in the paper.

The paper considers turning kinematics of structural carbon and alloy steels with imposition of directed asymmetric cutting tool vibrations on a conventional cutting pattern which are created by a cam system. An influence of tool vibratory motion parameters on crushing process of flow chips has been determined in the paper. The paper contains an equation of tool motion and reveals an influence of asymmetric coefficient of tool vibration cycle on slice thickness and dimensions of chip elements.

 

The paper reveals that the highest colmatation efficiency of charged and neutral particles is achieved in a polarizing electrostatic filter with a dielectric filter material which is placed in an electric field of high intensity created by surrounding metal electrodes.  Due to polarization of dielectric jumpers (dipole formation) strong electric charges are initiated on their surface and in consequence of these charges forces of Coulombic and induction particle settling are dominating there. These forces are considered as the most efficient mechanisms for settling of dielectric and electrically-conductive finely-dispersed particles.

The paper has investigated two methods pertaining to formation of  protective nano-structural vacuum coatings while using separated plasma flows. A comparatively technologically simple control method for crystallite size in the direction of coating growth has been developed in the paper. The method is based on the deposition of individual thin layers of high-melting  compounds of transition metals from separated plasma flows and periodical  bombardment of condensates formed by an ion flow. The executed X-ray diffraction analysis has shown that an application of the given method  makes it possible to reduce size of a coherent-scattering area up to 10–15 nm and ensure an increase of micro-hardness and corrosion resistance of the deposited coatings. Nano-crystalline Ti–Cr–N coatings with crystallite size of 10–20 nm have been obtained while applying a vacuum-arc deposition technique from  separated plasma flows. The paper demonstrates that purposeful alloying improves operational coating properties that allows to use the coatings  as protective layers which are deposited on the working surfaces of cutting tools.

The paper presents a kinetic model of CW electric-discharge CO₂-laser with fast flow. Expressions linking a non-saturated gain ratio, saturation intensity and output power of the fast-flow laser with excitation rates and relaxation times of laser levels have been obtained in the paper. The paper demonstrates that the higher excitation and flow rates or higher saturation intensity provide considerably higher specific output power of the fast-flow CO₂-laser in comparison with a sealed-off CO₂-laser. While maintaining a steady discharge the same output power of the fast-flow CO₂-laser may be obtained under various discharge conditions and combinations of fast flow rate, gas mixture composition and active media temperature.

The paper presents a theoretical investigation on nature of two-dimensional periodic circular movement of a work-piece attached to the end of a modernized sawing unit boom.  The boom oscillation axis is established on an elastic suspension that makes forced oscillations along a horizontal axis. The paper provides a calculation model of an oscillatory system of a boom swing block for mathematical description of the point movement trajectory that belongs to the work-piece. The model permits to obtain a system of two connected equations describing this movement. Numerical solution of these equations permits to establish that the work-piece makes a two-dimensional periodic circular movement and it has an elliptical  trajectory. The paper gives data that reveal influence of elastic and inertial and dissipative characteristics of the oscillatory system on the elliptical trajectory parameters of the work-piece movement. The paper demonstrates  that the regulation of the forced oscillation frequency transferred to the boom swing block of the sawing unit is considered as. the simplest in realization and the most efficient method that makes it possible to control the required parameters.

The paper presents results of the new developed approach to manufacturing of original topology using  photographic  masks  that allows to perform a real-time estimation of photolithographic  significance of the pattern defects on a mask being detected while controlling the correspondence of the photographic masks to the required topology.  In this case such operation as projection transfer of an image from the photographic mask to wafer has not been applied. The given approach excludes not only  single but topology group defects as well and also optical proximity correction structure defects.

 

The paper considers possibilities pertaining to application of multibeam antennas for communication systems. Modeling of a pyramidal horn antenna and lattice has been carried out in the paper. The paper studies methods for provision of multibeam radiation. Modeling and electrodynamic analysis of multibeam antenna systems have ben executed on the basis of single- and double-mirror antennas. The paper presents application of horn antennas of special design with the purpose to improve range characteristics of the system.

The paper demonstrates that while measuring yield of civil and industrial building and structure foundations the geometric leveling is carried out rather often with unjustifiably extra accuracy. Calculative examples of the required accuracy of leveling measurements are given on the basis of criteria in respect of  maximum allowable skewness of building structures in a vertical plain. The paper proposes to include a statement in a normative document that permits to apply inequality in respect of length of sight with its compensation in leveling line and correspondingly introduce exclusive standards to accuracy of a leveling alignment on horizontality of a directional ray.

The paper proposes graphic-analytical research methods for architecture systems of an ancient town as an optimal way to reveal specific space organization principles in a town which is subject to reconstruction. Content of some methods and conditions for their application are illustrated by the example of a medieval Belarusian town. The obtained results testify that the Middle Ages epoch was definitely an expression of national originality in urban building culture of Belarus.

The paper considers geological conditions for sedimentary mantle formation. In the geological past limestone deposits and sedimentation rock mass from fragmentary materials brought by water flows were formed in the southern part of the stretched geosyncline which had been submerged by shallow sea. By lapse of time deposits were transferred into sandstone, siltstone and mudstone that represented the bottom part of rock mass. Continental conditions were established as a result of orogenic process which took place nearly 30–50 million years ago. Erosional activity of wind and flowing waters was observed on the surface for a long period of time.

The top part of soil rock mass is represented by alluvial deposits of the rivers Tigris and Euphrates. During the process of sediment deposition more full-flowing Tigris caused more complicated dynamics of water channels  including meandering and changeability of inter-bedding.

Engineering and geological investigations have been carried out with the purpose to study structure of soil rock mass in various regions of the country (Al-Diwaniya, Khidr, Al-Nasiriya and Khila). Specific drill columns have been selected on the basis of analysis of soil rock masses.  Theses drill columns may serve for further selection of rational types of foundations (shallow foundation, piles foundation) or creation of artificial foundations (cementing, armoring etc.).

 

The paper contains an analysis of brake system designs pertaining to loaders of international manufacturers. Tendencies in their development modernization of road-construction machinery as whole have been revealed in the paper.

Provision and improvement of safety in respect of operated automotive and transport facilities is of great significance all over the world. This problem is rather actual for automotive transport in the Republic of Belarus.

An analysis of absolute and relative accident indices, operated automotive fleet, number of road traffic accidents caused by technical failure has been carried out on the basis of the results pertaining to operation of transport facilities in the Republic in 2011. The paper considers a role of technical state of road transport vehicles as a reason of transport accidents

The paper proposes a new method for approximate solution of singular integral equations with the Cauchy-type kernel which are taken along the real axis segment. Integration function can be represented as an asymptotic polynomial or infinite series using the Chebyshev polynomials. The remainder has been obtained simultaneously with the approximate solution. Its form makes it possible to determine degree of the polynomial that provides an approximate solution with a given accuracy.

The paper contains a virtual modeling 2D(r, θ) for deformation of singly-connected cylindrical solid under conditions of thermo-irradiation impact. Influence of a circumferential distortion on nonaxisymmetric strain-stress state for various values of temperature amplitudes has been investigated in the paper. A solid cylinder  with internal heat sources has been considered as a model body. Properties of the model body correspond to cermet fuel (40 % UO₂ + 60 % Cr).