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The sharpening of hard-alloy cutting tools affects their life and reliability and the quality of the machined surface. In the case of imported tools for high-precision machining, the rounding radius of the cutting edge after sharpening is 10–15 µm. That permits machining with chip thickness no less than 20–30 µm. This limit is often critical, since the machining precision of some important components is 3–5 µm. In addition, such sharpening shortens the potential tool life. If sharpening is improved so that the rounding radius of the cutting edge is 3–5 µm, the machining precision is enhanced and tool life is extended. That improves machining [2].

Pleurozium schreberi is one of the most common moss species in the forest area. It is dominant in the moss layer of blueberry and wood sorrel forests. It can occur in small quantities in almost all types of forests (even in bogs). It is also a typical component of the moss layer in tundra. The article considers the distribution of Pleurozium schreberi in the East European Plain and Eastern Fennoscandia. On the basis of literature sources on the occurrence of the species in different regions (according to point data), a model map of species distribution using the kriging-method has been created. The overlaying of the model map on the maps of spatial distribution of climatic parameters and vegetation zones in this area has revealed that the biogeographical preferences of the species. P. schreberi is characterized by its highest distribution in the forest zone. It often occurs here and represents a phytocenotically active species. The occurrence of Pleurozium schreberi dramatically decreases in the transition from the forest to the steppe zone, where it is a rather rare species, growing exclusively in pine and birch pegs. This species disappears in the open steppe. From the steppe zone to the south, the occurrence of Pleurozium schreberi gradually decreases with increase in summer temperatures and decrease in precipitation and with forest disappearance. In the north, where the species is highly active, its range abruptly ends on the coast of the Arctic Ocean. This pattern of distribution of Pleurozium schreberi is associated both with cenotic preferences and with climate: it becomes rare in regions with summer temperatures higher than +23°C and annual precipitation of less than 400 mm.

Methods of grinding and shaping the rear surface of hard-alloy polyhedral inserts are considered. Machining of the tool’s rear surface is simulated, and several kinematic configurations for margin removal are proposed. An algorithm for kinematic shaping of the rear surface of a hard-alloy polyhedral insert in CAD systems is outlined.

The present report is devoted to the discussion of the properties of two equations relatively long ago proposed by B. B. Kadomtsev for the nonlinear theory of ion-acoustic plasma turbulence and some results of their solutions. We concern with these equations as objects of mathematical physics, focusing attention to both the approach to their study and arising numerical results.

Besides traditional cutting tools, rotary tools are now being used. In view of their benefits, further research is advisable, with a view to their widespread use — in particular, in the machining of complex surfaces. The possibility of producing a helical profile by means of rotary tools in a traditional cutting configuration is mathematically established, with slip of the chip over the face (beginning at the larger diameter of a tapered tool).

It is proposed to consider the scalings of anomalous transport (superdiffusion), determined experimentally in turbulent plasma of the Earth’s magnetosphere and laboratory plasma of thermonuclear facilities and processed using modern statistical cascade models of strong turbulence with intermittency, also within the approach of physical kinetics to the theory of plasma turbulence.

A synthesis method for the reference trajectory of an unmanned aerial vehicle that flies around obstacles of urban buildings in the horizontal and vertical planes is proposed. To solve this problem, for the first time a conformal mapping is constructed for a collection of rectangles that approximate the obstacles on the digital map of a terrain.

The theory of turbulent heating in the mode of hot deuterium ions and cold tritium ions is developed for plasma with equal deuterium and tritium ion concentrations. The possibility of heating electrons and deuterium ions by thousands of times is shown.

To extend tool utility, we may regard worn hard� alloy cutters as blanks for further machining. We must take into account here that the cost of new highqual� ity hard alloy is as much as $10 per kg, while experi� ence in regrinding shows that plates with normal wear (without catastrophic wear) are free of internal defects.

An unimprovable lower estimate of the upper limit of the ratio of the sum of sine series with monotone coefficients to its majorant is obtained.

The restoration of worn axial hard-alloy mills by diamond grinding and sharpening is considered. Equipment based on the 3A110 grinding machine is employed. The influence of the machining conditions on the productivity and tool life is studied.

The grinding of flexible high-precision broaches is considered. Various basing systems for the broaches are analyzed in terms of productivity and machining precision. The flexure of the broach as a result of the cutting force in different basing systems is determined by calculation and experiments.

Parameters affecting the dimensional precision of machined surfaces include the tool deformation in machining. The cutter is one the principal elements of a rotary tool that affects the dimensional precision, and correspondingly its deformation is very significant. By calculation, the cutter deformation in rotary tools may be established during finishing and roughing and also in primary and secondary cutting configurations.

In this paper we develop a one class of solutions of the steady Vlasov-Maxwell equations, which describes two dimensional cylindrical current sheets with current directed azimuthally j = jθ(ρ, z)eθ. Magnetic field of these sheets has two components B = Bz(ρ, z)ez + Bρ(ρ, z)eρ. From mathematical point of view, we find solutions of the nonlinear equation in partial derivatives for some function u(ρ, z): ∂2u/∂x2 + x−1∂2u/∂z2 = e−u, where x = ρ2. We apply methods of group theory to develop three-parameter class of solutions. We also derive asymptotic behavior of these solutions for large values of ρ and for ρ ∼ 0. We discuss applications of these solutions for description of current sheets in magnetospheres of planets with magnetic dipoles located near the ecliptic plane.

We consider the problems connected with the computational abilities of a neuron. The orderings of finite subsets of real vectors associated with neural computing are studied. We construct a lattice of such orderings and study some its properties. The interrelation between the orders on the sets and the neuron implementation of functions defined on these sets is derived. We prove the NP-hardness of “The Shortest Vector” problem and represent the relationship of the problem with neural computing.

The analytical and numerical dependences of the total transverse current on an electric field, the normal component of a magnetic field and the ion and electron temperatures are obtained using analytical approximation of numerical results provided by a self-consistent model of the magnetospheric thin sheet. The dependence of current on the parameters ɛ, T i , b n is shown to be nonlinear. The relative contributions of different plasma components into the total current are estimated.

Turbulent heating of plasma particles in the mode of strong heating by hot ions and weak heating by cold ions, where the turbulent state lifetime is not limited as in the case of heating by ions with equal temperatures, is discussed.

The creation of a hard-alloy metal-cutting tool for the finishing of materials that are hard to machine is considered. To improve the machining quality and productivity, the use of a tool with 1-μm sharpness is proposed.

The structure and mechanical characteristics of ceramic composite materials based on titanium and hafnium diborides produced by reaction sintering in the course of hot pressing have been studied. It has been shown that ultradispersed structure is responsible for high mechanical characteristics of the synthesized composites.

The efficiency of cutting tools for composites used in the aviation industry is improved. An end mill for which the rounding radius of the blade is

The use of lubricant and coolant fluids permits improved machining quality and longer life of metal� cutting machines. The primary functions of such flu� ids are to reduce the temperature in the cutting zone and to minimize the frictional coefficient. These roles are interdependent: with increase in temperature, the adhesive component increases; with increase in fric� tional coefficient, the cutting temperature rises. Metalworking enterprises use different lubricant and coolant fluids for different operation. Watersolu� ble (emulsions and synthetic fluids) and oilbased mixtures are used, with concentrations of 2-10% (1). Synthetic lubricant and coolant fluids are of most interest, since they present fewer biohazards than do emulsions. The lubricating action of the fluids is mainly seen at chip-cutter contact and also blank-cutter contact. It is associated with the fluids' ability to participate in physical, chemical, and physicochemical interactions with the activated surfaces in the contact zone and to form hydrodynamic, physical (adsorptive), and chem� ical lubricant films. Depending on the cutting condi� tions, such films may be formed individually or simul� taneously. Physical and chemical lubricant films are said to be boundary films. Their thickness varies from to tens to hundreds of Angstrom. Their shear resistance is higher than for hydrodynamic films. When hydrodynamic lubricant films are formed in metal cutting (for exam� ple, in the lowspeed cutting of copper), the frictional surfaces are separated by a few microns of fluid. The viscosity of the lubricant and coolant fluid is of most importance here and must be optimal. Sometimes, the viscosity may be compensated by additions of sulfur, chlorine, or phosphorus compounds. The lubricant and coolant fluid may be selected by determining the actual frictional coefficient of fluids in machining some material and also their cooling properties, so as to improve the quality of machining (the dimensional and shape precision, the surface roughness and microstructure, etc.). The actual frictional coefficients of synthetic lubri� cant and coolant fluids in conditions resembling their working conditions may be determined on an II 5018 frictional machine, using a frictional shoe (T15K6 hard alloy) and a roller (steel 45). In the present work, we consider Biosil S, Isogrind�130EP, AkremonD�1, KonkrepolVTs, and Ekol�3 fluids, at a concentration of 10%. The force on the shoe P = 800 N; the roller speed n = 250 rpm. The table presents the results for the machining of steel 45 using synthetic lubricant and coolant fluids.