Vol 23, No 4 (2015)

The paper presents a detailed example of adaptive planning of communication sessions for the International Space Station (ISS) orbit correction. The description of both the ISS orbit correction scenario and the criteria of its planning are provided. A conceptual model of flight operations planning is designed, as well as the description of the criteria and constraints of task execution in a group flight operation. The input and output data are described. The ISS orbit correction scenario is modelled.

The paper deals with the problem of modern information technologies in the public health system. It is shown that the human genome should be placed to the heart of the modern information system designed on the basis of the web-based platform of personalized medicine. The requirements to the web-based platform tools are formulated. The basic modules which comprise thefunctionalof theweb-basedplatform are outlined. The paper offers the architecture of the web-based platform and describes the principles of the projectscaling. On the basis of the three-tier client-server architecture analysis, a stack of techniques requiredfor the projectis selected. The issues of horizontal scaling and system-time scaling are discussed. The principles of designing an intelligent decision support system as part of the web-based platform are proposed.

This paper discusses a new method of measuring capacitive sensors parameters by the transientsinstantaneous values inthe sections of a measuring circuit comprising two model elements. In contrast to the known methods based on the determination of thecapacity of the individualtransients instantaneous values, the implementation of the method provides a separate determination of both the capacity and insulation resistance of a capacitive sensor and the resistance of the conductor connectingthe sensor to the measuring circuit. It improves the accuracy of the information parameter measurement. A block diagram of the measurement tool which implements the method is offered. The results of the analysis of theinfluence of thetransients instantaneous - values quantization on the capacity determinationerror are presented. Using the results obtained, it is possible to make the optimal choice of blocks in accordance with the requirements for measurement accuracy.

The paper deals with a vibration isolation system with an actuator in the form of a magneto-rheological damper. A calculation scheme of a single-mass single-degree-of-freedom vibration system is presented. On the basis ofthe obtained differential equations of the vibration systemdynamics, a structural scheme for the investigation into its dynamic performance is designed. On the developed experimental apparatus, the study of the vibration system dynamics under the conditions of the discrete change of the controlling actionon the actuator is made. The experimental values of the relative amplitude of the protected object movement are received for the various vibration frequencies. The experimental data received are approximated by the analytical expression of the amplitude-frequency response. The constant and variable efforts appearing on the damper rod are calculated. On the basis of the calculated data is established the dependence between an increasein the controlled-damperresistance force and an increase in the damper-coilcurrent.

Position-tracking systems with numerical control are fundamental for the synthesis of electric drives for metal-cutting machines and, in particular, for jig-boring high-precision machine tools. In the structure of such systems,CNC commands are transferred to the power amplifiers feeding the machine moving-parts electricmotors by means of a zero-order predictor. The latter’s discreteness causes an error in the reproduction tasks in dynamic modes, which are typical of the processing of complex - profile products. The paper deals with the estimation of the dynamic error coming from the discreteness of the predictor, and provides recommendations on the formation of the tasks for the implementation of the constant (predetermined) productivity technological process.

Using the integral method of heatbalance, was developed a method of analytically solving the problem of heat-transfer for liquid flowing in a cylindrical channel under first-type boundary conditions on the pipe walls. This method is based on the use of an additional sought-for function and additional boundary conditionsdetermined in such a way that the sought-for function would satisfy the original differential equation in the boundary points. The additional sought-for function shows the temperature changing in the centre of the pipe as depending on the longitudinal variable. Because of the heat-propagation infinite speed described by a parabolic equation of heat-conduction, the temperature in the channel centrewould change immediately after the application of first-type boundary conditions onthe cylindrical channel surfaces. Therefore, the region of the additional sought-for function change includes the entire temperature and longitudinal spatial-variable change range. This approach allows the solution of partial-derivatives differential equation to be reduced to the integration of an ordinary differential equation with respect to the additional sought-for function only depending on the longitudinal variable. The paper shows that, through the use of the additional sought-for function and additional boundary conditions, and with the increasing number of the sought-for solution approximations, the original equation would be satisfied not only at the region boundaries (via the implementation of the additional boundary conditions), but also inside that region.

The paper discusses the problems of oil-field pipeline corrosionprotection. In oil fields, a special danger consists inthe pipeline internal corrosion, as the pumped aggressive liquid has a high-rate mineralization, high concentration level of hydrogen sulfide, carbon monoxide and other impurities. The problem of corrosionprotection can be solved by application of pipes with a silicate-enamel coating. The paper deals with an installation for applying a silicate-enamel coating for the internal welded-seamprotection. The conducted research of pipe silicate-enamel coatings has showed that with the coating thickness of 300 - 400 microns, the ensured corrosion protection of the pipe primary metal is up to 40 years.

The paper describes the structure of a flexible pipe used in oil fields. Themechanical properties of the three materials comprising the pipe structure(polypropylene, polyvinyl chloride, and high-density polyethylene from which the pipe hermetic inner chamber, damp proof layers, and load-bearing components are made respectively) are studied. The selected objects of study are to determine the tensile stress of the materials in question, as well as to determine the efficiency of polypropylene twine twisting during the pipe assembly.Theproduction of the samples for material testing, and the test conditions are described, the photos of the samples being presented. The values of ultimate tensile stress, offset yield point and Young's modulus for each of the three polymers are obtained, the graphs of the dependency of loads on deformation magnitude being given.

The paper deals with using magnesium alloys as protectors. The characteristics of the magnesium alloys used for tank corrosion protection are provided. The general views of protectors before installing them into the tank and after utilizationare presented. The characteristics of the usedpassivator base are offered. The results of the coating characteristics determination testing are shown. The paper also gives recommendations on the determination of the tank protector materials, their dimensions and their usage sphere depending onthe oil storage method. The authors come to the conclusions about using passivatorsfor corrosion protection.

The paper covers the basics of a data-analysis system for the design, analysis, and simulation of intelligent networks and control systems. The system comprises a graphical modeling environment, agents for the communication with the control system, instruments for data monitoring and visualization for the operator. This approach has the advantage of the possibility of the control system being tested and made optimal according to the modeling environment, and the final model can then be used in the control system to predict the distribution networkbehavior.

This paper is devoted to using of the finite element method for stress-strain state of the pipe threaded connection. A model of casing threaded connection (diameter 168 mm, thickness 8 mm) is created. A dependence of the butt-end move from the stretching force is determined. A comparison of the results with the traditional calculation method is followed. Also dependence of linear force from the number of thread is determined. It is achieved that pipe connection retains its properties only after single screwing. Also it is determined that the connection bearing strength is greater than the value determined by Yakovlev-Shumilov formula.