Problem statement. The use of existing and the most widespread drives (wheeled and caterpillar one) is sometimes limited by complicated operational conditions while moving on rough terrain. The mentioned drives require a relatively flat surface to be operated effectively. A rocky or a hilly terrain imposes the demand of the use of alternative types of drives, in particular, walking ones.
For the first time, oleochemical sulfanes were synthesized via sequential vulcanization of fatty acid alkyl esters from rapeseed oil by benzoyl peroxide and elemental sulfur. Their structure and properties were established by the methods of instrumental analysis and it was shown that oleochemical sulfanes are complex structures with different cross-linking degrees, which provide excellent antioxidant and tribological characteristics and do not cause steel or copper corrosion under harsh test conditions.
The article offers system engineering solutions for enhancing the single-phase autonomy of the processes of controlling the coordinates of electrical mode (EM) in an electrical mechanical sub-system of moving the electrodes of an electric arc steel-making furnace by including a cross-link compensator into its structure.
The possibility of synthesis of heat-resistant steels metallothermy are set as a result of theoretical and experimental work. The influence of the method of synthesis on metallothermic features of the microstructure and phase composition of the thermite steel was found. The mechanical and service properties and their dependence on temperature and the effect on the properties of the alloy grain thermite metal are set for thermite synthesized analogues of industrial heat-resistant steel grades “40Х15Н7Г7Ф2МС” and “37Х12Н8Г8МФБ”
The paper considers differential equation of the vibro-impact resonance system with an asymmetric piecewise linear elastic characteristic. The time-instant of switching of elastic characteristic is determined on the basis of equality of oscillation period to average value of the corresponding eigenfrequencies. Then, expansion of the asymmetric piecewise linear elastic characteristic into Fourier series was made. The initial differential equation was reduced to a kind of parametric equations of Hill’s andMathieu’s type with taking into account the time of elastic characteristic change.
The analysis of movement modes of cam mechanisms is carried out. The technique of optimum movement modes synthesis is proposed; it allows to receive any modes which reflect certain properties of a cam mechanism. Complex optimum movement modes which simultaneously take into consideration several properties of cam mechanisms are most promising. Such optimum movement modes can be received on the basis of complex criteria taking into account optimum movement modes of cam mechanisms by single integrated criteria.
In the paper the behavior of an intelligent agent in a competitive environment is investigated in the paper. The OODA loop is chosen for behavior simulation. The interaction of OODA loop stages (observation, orientation, decision support, action) with the ontology of tasks and subject area in which the agent operates was explored.
The paper analyzes the shortcomings of existing models of text documents, it proposes an uniform content model of text that formed on the basis of synthesis of logic and linguistic models of its sentences. The work shows basic steps of the proposed algorithm for constructing content models of text
A new series of methyl 4,6-O-(4-methoxybenzylidene)--D-glucopyranoside derivatives was synthesized using the direct acylation method. Methyl--D-glucopyranoside was selectively converted to methyl 4,6-O-(4-methoxybenzylidene)--D-glucopyranoside by the reaction with 4-methoxybenzaldehyde dimethylacetal in a reasonable yield. Using a wide variety of acylating agents, a series of 2,3-di-O-acyl derivatives of this product was also prepared in order to gather additional information for structure elucidation.
Porous spherical materials can be obtained by suspensions polymerization using a solvent pair. In this work porous resins based on methyl methacrylate and divinylbenzene were synthesized and characterized in terms of apparent density, specific area, pore volume, morphology, and swelling percentage. The results show that the diluents system (toluene/heptane or methylethylketone/cyclohexane) affect significantly the polymer properties. Furthermore, differences in the solubility parameters of the monomers and diluents affect the morphological structure of beads.