Vol 22, No 3 (2014)

The two-circuit system of stabilization of temperature for oil air-cooling unit is synthesized. The block diagram of stabilization temperature is developed. Parametrical synthesis of the regulators is made, allowing to adjust a control system of the device of oil air cooling on desirable character of transient process. Quality regulation areas of the developed system are constructed. The technique of parameters choice of regulators is developed.

The structural scheme of the medical systems of differential diagnosis is considered. The expert system architecture was made by three-layer architectural templates. Web-based technologies in developing of application server allows to distinguish between the logic levels, data access layer and the presentation layer. System kernel with the use of object-oriented architecture is developed. An outline interface with the database to solve the inconsistency of data presentation in the system is offered. The mode of obtaining medical knowledge and health consultation mode during the expert system work are shown. The developed expert system allows to provide medical diagnostics in real time in the conditions of uncertainty of information.

The paper describes last trends in Internet advertisement area - keyword/key-value terms and optimization methods used based on keyword statistics. Article covers technical process of ad-deliveries, different optimization methods and their comparative analysis on real life scenarios.

The problem of nonlinearity characteristics correction of modern microsensors, with use of approximation discrete characteristics is considered ​. Linearity correction is performed with the use of either direct or inverse characteristics of the sensors. As approximating function of the sensor characteristic a cubic spline - function is used. Approximating function is done by the microprocessor analog converter. The schemes of correcting converter with a functional transducer in a straight chain as well as in a negative feedback of the buffer amplifier are considered. The proposed device can reduce the nonlinearity error sensor characteristics in a few dozen times.

Methodological approaches for measuring and monitoring basic metrological characteristics of chronometer technical means are discussed in this paper. Difference between different approaches in measurement and control of the basic metrological characteristics of timekeeping hardware - instantaneous diurnal variation is shown. Algorithms suitable for performing a metrological evaluation of instantaneous diurnal variation measuring and determining the absolute accuracy of the diurnal variation of the instantaneous control are proposed. The obtained results allow to make a correct methodological approach for analyzing the measurement and control processes in the field of chronometry, as well as in practice of measurement and control of physical quantities.

Optimal parameters of electron beam welding (EBW) of heat resistant alloy 20Cr67Ni5W4Mo3Ti1Al of 6 mm thickness, with a technological lining of 5 mm thickness without preheating were found. The influence of EBW regimes on defect formation was investigated. Propensity of 20Cr67Ni5W4Mo3Ti1Al alloy to the formation of defects was studied at welding speed of 3 and 5 mm/s. To evaluate the welding quality each of the samples was subjected to X-ray inspection, cutting, metallographic study with the definition of the geometric parameters of welds, microhardness and the defects presence. The obtained values of the welding parameters of butt connections provide the required quality and size of the weld.

The aspects of appearance and effect of thermal deformations of machine tools are considered in this paper. On the design of the spindle unit the factors affecting the formation of the thermal patter are examined. Heat sources of spindle assemblies are defined. The process of heat flow through the joint parts is described. The technique of forming a thermal model of the machine tool spindle assembly with the heat flow through the connection with the thermal resistance is developed. On the basis of numerical simulations the effect of quality of treatment, wetted parts, the convection of conjugate parts of the material in the depressions and micro- macroroughnesses on the thermal conductivity of the contact are estimated . The influence estimation of these factors with the account of the effect of time parameter, the value of real contact area and its location within the area of conjugation is made.

Improvements of cam-gear motion law are examined in the paper. The goal of the study is to adjust the cam-gear motion law on the basis of existing motion law analysis to balance the action of different factors. Today the synthesis of cam-gear motion law is produced without the account of the deformation energy of structural elements. The algorithm for correction the motion law taking into the account the deformation energy of the cam-gear and contacting elements is suggested in the paper using a slay mechanism of a weaving machine as an example. Structural modifications increasing the rigidity of load-carrying system and slay mechanism elements are carried on to diminish the forces required to deform the construction elements. As a result of the research, a new motion law of the mechanism is proposed. It allows to decrease power loss twice during the work of the mechanism compared to the existing law and to decrease contact tensions in a fist-roller pair.

The aspects improving the design procedure of electric power transmission charge are considered. They allow to eliminate legal barriers concerning extra charge or increasing factors to charge for volt-amperes reactive transmission of excessive limit values. The new methode assumes that the charge calculated by means of the existing approach excludes the cost of losses related to volt-amperes reactive transmission of excessive limit values. In practice this method makes possible to influence the consumers positively and regulate the volt-amperes reactive conditions. The improved design procedure of electric power charge regulates inconsistent relations between consumers and net organization concerning increasing factors to charge for exceed limit values of volt-amperes reactive and active power. It is done in accordance with “The recommended guidelines to the design procedure of increasing (decreasing) factors to transmission charges depending on consumption correlation of volt-amperes reactive and active power for power receivers (groups of power receivers) applied to determine the obligations of parties for service agreement on electric power transmission by means of the joint domestic (the Russian Federation) electric network (energy supply agreements)”.

Numerical simulation of the flow field in a tank with a Rushton turbine is carried out by the control volume method. The profile of the free surface in the tank is computed as a part of the solution by means of an iterative technique. The results are presented as streamline contours of the secondary circulation .

High-viscosity oil field development with dual-well system gives an opportunity for increasing oil extraction with periodic lay heating. The effect is reached by putting of solid-fuel source on the bottom of vertical hole and fluid recovery from addictive rat hole drilled beyond lay desctructive zone. Technical decisions of using small-sized downhole pumping equipment allow to optimize heating and extraction processes. Vertical bottom hole deviation with reservoir heating radius is determined.

Mathematical description of the open evaporation process of substances from accumulators of oil slime is given. The analytical solution researches of the allow to identify four basic parts of the evaporation process of hydrocarbons from exposed surfaces depending on the values of criterion numbers. The results obtained suggest a simplified mathematical model of open evaporation of hydrocarbons confirming the existence of these parts. The substances evaporation from the surface of oil slime is limited by the diffusion rate of substances in the liquid phase. The dependence of the diffusion coefficients of volatile substances from the temperature and molecular weight is received.