Comparative analysis of the effectiveness of monolithic and cyclic noise protective codes built on "Ideal Ring Bundles" (IRBs) as the common theoretical basis for synthesis, researches and application of the codes for improving technical indexes of coding systems with respect to performance, reliability, transformation speed, and security has been realized. IRBs are cyclic sequences of positive integers, which form perfect partitions of a finite interval of integers. Sums of connected IRB elements enumerate the natural integers set exactly R-times.

A Modeling Study of Operating Conditions and Different Supports on Fe-Co-Ce Nanocatalyst and Optimizing of Light Olefins Selectivity in the Fischer-Tropsch Synthesis

This study demonstrates the effect of operating conditions (Red-GHSV, inlet H2/CO, Oprat-GHSV) and the effect of Fe-Co-Ce nanocatalyst support. A statistical model using the response surface methodology (RSM) was applied with the target of achieving higher olefins selectivity in Fischer-Tropsch synthesis, which indicates the interaction effects of factors. The conditions under which three objectives optimization for maximizing olefins and minimizing paraffins and methane were determined.

Application of Response Surface Method to Copper Cementation by Metallic Aluminum Particles

In the present study, the interactive effects of the process variables containing copper concentration, temperature, and time on the efficiency of copper cementation by metallic aluminum particles were examined by using response surface methodology (RSM). It was observed that the efficiency of cementation increased with an increase in the initial concentration of copper, temperature and time. The multiple regression analysis to the experimental data was applied to see the interactive effects of process variables. The second-order polynomial equation was obtained.

Vibration impact and noise protection devices with DVA for wheeled vehicles

The article investigates vibration and noise protection devices for wheeled vehicles using dynamic vibration absorbers (DVA). Algorithms for modeling their dynamic characteristics based on adaptive calculation schemes are presented. A non-linear suspension with DVA and a noise-absorbing partition is considered, which is due to the introduction of a layered composite thinwalled structure with an intermediate damping layer with high damping properties and a DVA system, which provides better vibration and noise absorption.

Theoretical basis of energy efficiency criterion-based optimal control of arc steel-melting furnace modes taking into account 3-dimensional phase current distribution

The purpose of the article is to develop a method for synthesis of the operative adaptive optimal control of the electric mode (EM) of an arc steel-melting furnace (ASF) by energy efficiency criteria based on three-dimensional (3-D) distribution of arc currents. The basis of the created method is the use of operative information on the parameters of 3-D distribution of arc currents and the search for the appropriate optimal control – set points for arc currents of a double-loop system of controlling the electric mode of an arc steel-melting furnace.

Features of business processes modeling and Its optimization in the context of international activities

Transformation of approaches to business processes modeling in the context of international activity is an effective solution for finding options for expanding the organization's activities, forecasting and minimizing potential risks. The chosen topic is relevant for the study, as the current market conditions are increasing the role of the use and implementation of modern methods of modeling and optimization of business processes in enterprises.

Analysis of measurement systems mathematical models by using the comparison of functions

We propose an approach to mathematical modeling for a system on the basis of comparing scalar products in spaces of real functions integrable on the segment.  This approach may be used in discrete and continuous measurement systems and some combinatorial systems, in which comparison problem of function exists in the process of synthesis and optimal choice of their parameters.  In theory, such problems are characteristic of boundary value problems for equations of mathematical physics, in particular for multi-point problems that describe oscillatory processes in mechanisms.  We have found th


The development of technology for production of metal-filled hydrogels based on copolymers of 2-hydroxyethyl methacrylate (HEMA) with polyvinylpyrrolidone (PVP) by polymerization with simultaneous chemical reduction of metal ions suggests the grounding and determination of optimal technological parameters for its realization. The diverse influence of the initial polymer-monomer composition (PMС) formula on the main parameters of the exotherm of the copolymerization of HEMA with PVP, which constitute the technological mode of chemical deposition of metals, was experimentally proved.

Development of PI-controller optimal tuning method

Aim. The research aims to develop a method of optimal PI-controller tuning, which allows to take into account the constraints and to minimize the undesirable indicators of the automatic control quality. Method. In order to carry out the investigation, the problem of optimal PI-controller tuning was stated in a general form. The analysis of the elements of the problem has been conducted. It allowed substituting the elements to the requirements of individual minimization criteria.