Vol 20, No 3 (2012)

The place of cost estimation in the set of designing and operation processes for engineering systems is discussed. The function formation characteristics of the value appraisal involved in interpreting the results of this evaluation are given. A variety of options for the relationship between the function of the value appraisal and cost limits that affect the purchasing of system components is shown.

The paper describes one of the possible models of interaction management of active software components in the P2P network of the enterprise. It is proposed to study the problem of resource allocation using Auction model enhanced by the opportunity to manage the Auction process changing its dynamical characteristics. The approach shows that the introduction of delays and accelerations allows to increase the efficiency scheduling solutions.

By application of Laplas's method of integration to the equations in the partial derivatives describing the temperature field of a petroleum product, the ratios for the transfer functions of the operated object having been obtained.

The article consider an analysis of the temperature error in the thermo-correction channel of the system for information acquisition about blade tips displacements. Quantitative estimates of this error are obtained and inaccuracy-reduction technique is proposed. A possible implementation of the proposed method is considered.

This article analyzes the natural self-purification ability of a body of water. The key parameters that determine the self-purification ability have been found. The structure of information measuring system is presented making possible perspective forecasting for the state of a body of water environment.

A method to estimate the impact of instability of communication lines and secondary transformation circuits on the precision characteristics of pressure measuring systems for high-temperature liquids and gases with primary capacitance transformation is discussed.

Classification of methods of measurement of integrated characteristics by instant values with use of orthogonal harmonious signals is considered. The new approach to the synthesis of such methods is offered. Four methods synthesized on the basis of the given approach are examined.

The formal method which develops the principle of two channels into a technique of invariant measuring converter designing is presented. Its applications in the designing of two-channel measuring bridges and voltage dividers for special purpose devices and systems are discussed.

In the article the conditions of part wedging in assembly of assured gap joints are investigated.

This paper presents a methodology of modeling of rolling bearings as a solid ring with elastic properties identical elastic properties of the real bearing. A sequence of selection of the material properties of a solid ring to simulate the elastic characteristics of the roller bearing double-row tapered 4-697713L.

The roller strengthening influence on the endurance limit during bending of 25 mm diameter samples of steels 20 and 40Х with pressurized hub is experimentally researched. It has been found that roller strengthening increases the endurance limit considerably, especially of 40Х steel samples. The estimate of surface strengthening influence on the endurance limit by means of the residual stress criterion on the surface, and average residual stresses has shown that to forecast increasing the endurance limit of strengthened samples with a pressurized hub can be recommended to use the average residual criterion.

The research on the milling of D16T aluminium alloy has been done. The influence of cutting modes on cutting forces in milling operations, the roughness of surface, and the temperature of the workpiece treated surface have been estimated. Practical recommendations are given for manufacturing according to the cutting modes of milling.

The ways to improve heat transfer between the pipe wall and the moving fluid in an indirect induction heating system are discussed. The features of hydrodynamic processes while using turbulators are analyzed.

This paper describes a power system mathematical model developed by MATLAB for research on differential protection of transmission lines for 10-220 kV voltages.

In this paper the mathematical model of the DC series excitation motor drive with the motor voltage and current feedback and the elastic linkage between the vehicle mass and the mass of cargo is considered.

Solving the problem of increasing the efficiency of renewable power sources in the local electricity supply system, the operational power supply risk of consumers should be taken into account. The method of calculating the OPRC based on the theory of portfolio analysis is offered. It was made the quantitative assessment of the OPRC, that shows that the combination of diverse renewable power sources in the local electricity supply system increases the efficiency of its use and reduces the operational power supply risk of consumers.

The questions of applying a technique for producing a chart of an interface of non-productive structural elements are discussed. A method of system decomposition into levels (structures) which are monad morphisms by using topological and category-functor representations of the transport system is proposed. It will allow to reveal interface operators of diverse formalization models in creating the knowledge base of an information and analytical complex for analyzing the state of the transport infrastructure.

A theory of viscosity measurement by using a rotation technique, the operation principle and the design of the developed viscosimeter are described. A new way of measuring signal processing by intermediate transformation into a time interval is proposed. The methods of increasing viscosity measurement accuracy are given.