Vol 21, No 2 (2013)

The problem of optimal location of measurement points of the state function of non-steady heat conductivity process to minimize the approximation error is solved . It is considered an uniform error of approximation of Green's function of identified plant by Green's function of investigated boundary value problem.

A structural modeling of distributed system that may automatically control the temperature of the polymer melting in the metering zone of one-worm extruder as an object with distributed parameters under the distributed disturbances influence is given in the paper. Based on that a numerical model of the system has been synthesized and debugged, and its transient response is received.

The devices for disbalance measuring of differential parametric (resistive, inductive, capacitive) sensors are regarded. They are based on two–channel principle (structural and algorithm excess) providing measurement invariance to non–informative sensor parameters and affecting environment factors are considered. The schemes of base transformers are given.

In the paper the problem of the gas emission determination of the construction materials that used in spacecrafts is considered. The data measurement system for gas emission designation of the construction materials in temperature increasing conditions is described.

In this paper the investigation results of dynamic characteristics of controlled magnetorheological damper are given. Dependence parameters of the flow friction characteristic of controlled magnetorheological damper on the angular frequency oscillation of its movable part and the current in the coil of an electromagnet are determined. Dynamic characteristics of controlled magnetorheological damper were found to be close to those of an aperiodic link.

The paper studies the influence of mixing time of initial powders of tungsten and cobalt carbides on the properties and structure of sintered hard alloy Wc-Co10%. Optimum mixing time of mix material for drilling alloy Wc-Co10% on the basis of high-temperature tungsten carbides is determined.

The paper investigates the possibility of use of various binder materials for metal-polymer compositions for the manufacture of MIM technology parts. Foreign patents have been analyzed and the main criteria have been developed for selection of the binder. The paper gives the examples of different types of binder materials, and demonstrates their advantages and disadvantages. The results have revealed the promising trend in the application of the binder for MIM process.

The paper gives the results of development and identification of physical and design models of the outwearing, based on kinetic thermo fluctuation approach to estimation of the mechanism of damageability accumulation and corruption of the details outer zone deformed by friction. There has been demonstrated a new method of a sclerometric estimation of energetic characteristics of a material, as well as the possibility of this method to predict wear resistance based on empirical results of sclerometric tests.

The purpose of the given work is carrying out of comparative theoretical researches of a tension of firm fabrics of tooth for cases of application various pins designs of devices of fastening of a demountable tooth blocking artificial limb. For research carrying out the mathematical model of considered kinds pins designs has been constructed. The numerical decision of the turned out problem had been made calculation of pressure for two kinds of loading approached to real conditions. The obtained data allows to draw a conclusion that the offered design pins devices with the hemispherical termination, a root cap and a part of the oval form in a fang mouth leads to decrease in values of arising pressure.

The research results of damping capacity of heavy-loaded contact in the persistent bearing of boring chisels rolling cutters in case of the intermediate elements of the persistent bearing are made from composition materials are given.

A method of setting an adequate distance relay based on the creation of variable speed models of relay protection and automatic variable speed for modeling complex real-time power systems. The model of distance protection SHDE2801. Adequacy of the proposed methodology.

Refinement of the integral elements method is presented, which is used in approximation of the distributed parameter control objects

The problem of synthesis of fuzzy control system at a plant with distributed parameters is discussed. An approach to the construction of a fuzzy controller based on a modal representation of the plant with distributed parameters is analyzed. Time modes of spatially distributed signal of mismatch are considered as the linguistic variables. The membership function of fuzzy logic controller output is used as a spatially distributed control signal.

The mathematical model of operation of trunk pipelines for petroleum transportation is presented in the form of the linear differential equation of the second order with homogeneous boundary condition of the second sort for which the decision is received by Fourier method (separation of variables).

The main methods of condensation heat transfer enhancement in heat exchangers of oil refining industry are analyzed in the paper. The design of a new condenser on the basis of a vessel with vertical contact grids is suggested. A laboratory unit for the analysis of heat exchange in condenser with vertical contact grids is considered.

The problem of synthesis of the system of control of a diffusion process is described. Representation of the control action is based on the modal description in the form of the infinite expansion in terms of orthogonal system of eigenfunctions, the coefficients of this series are temporary modes

This article describes how to implement a system of measuring the angular displacement and motor speed, using a contactless encoder, which was sold by Austriamicrosystems company. Analysis measurement error and the analytical expression for resolution are presented.