The task of selecting optimal coordinates of the switching cycles at which the controlled process performance attains a maximum is formulated. This is some refinement of the optimal control problem applied to the machining processes for the case when the treatment mode control providing stabilization of various cutting conditions occurs. A typical example of such a problem necessitating the treatment mode switching for deephole machining with twistdrills is given. The necessary optimum condition to which minimum velocity values equal among themselves correspond is proved. On this basis, a velocity calculation technique providing the time minimum is proposed. A concrete example for the case of deep pinhole machining (diameter — 2.15 mm, hole depth — 140 mm) is given. The obtained results are generalized in the case when problems on any evolutionary system control machining are solved.

The inadmissibility of the comparison and cooperative processing of the conditional probabilities calculated with the use of the known variations of Bayes formula considering a well-defined amount of the accumulated evidences is established. This statement is justified as follows. Due to the unequal normalization, the results leading to the conclusions mismatching the probability-theoretical law are obtained. The examples of the concrete initial data show that in the case of using the traditional formulas, the multiplicative effect is missing: reducing the posteriori conditional probabilities of each of the hypotheses under the multiplicative accumulating evidences is unfeasible. The Bayesian formula modifications are offered. They provide a well-defined quantity of sequentially accumulated evidences constructed through the common divisor which is equal to the sum of the values of all normalizable probabilities liable to comparison or cooperative processing. In contrast to the well-known formulas, due to the correct normalization, the results significantly more adequate to the initial statistics are obtained.

Статья посвящена анализу современного состояния и перспективам развития технологий соединения материалов, таких как сварка, пайка, склеивание в европейских странах и в промышленно развитых странах мира. Показано, что темпы роста сварочного производства в различных отраслях достигают 8 % в год. По объёмам выпуска сварочного оборудования, роботизированных комплексов и сварочных материалов в лидеры выходит Китай. Значительный прирост объёмов сварочного производства наблюдается в развивающихся странах Азии, Африки и др. Большое внимание в статье уделено тенденциям развития стандартизации и сертификации в сварочном производстве, проблемам квалификации персонала.

A theoretical model for determining temperature on the working surfaces of the tool with the blade shaped profile is considered. Analytical dependences for estimating the thermal state of the blade front face (tooth cutter) with an elliptical profile in normal sections are obtained. The resulting equations include the effect of thermophysical constants of the tool material and workpiece, heat transfer conditions, deformation characteristics of the cut layer, cutting modes, and tool geometry (under turning and milling)on temperature. The obtained numerical results for the temperature of the HM tool (T15K6) and HSS tool (R6M5) match the test data; they can be applied to predict the wear rate and service durability of shaped tools including blades, side and hob cutters.

A proposed new model of the wireless sensor net can be applied for the network optimized energy efficiency. The optimization of the communication structure between nodes taking into account the capacity of the power supply unit, the amount of the information collected and transmitted by the node, as well as the energy connectivity between nodes and its quantitative assessment contributes to this. The application of this model will allow optimizing the structure of energy consumption in a wireless network to increase the time of its offline operation. (It is a case of life to the first node failure due to the power supply exhaustion.) The presented model is given in terms of the graph theory. The research relevance is proved. The approach to the problem solution based on the solution to the corresponding linear programming problem is described. The implementation of solutions in the form of a computer program is considered. The computer simulation results are described. The conclusions regarding the applicability of the technology in practice are provided.

The development of scientific principles, methods, and techniques of the automated control of the primary data recorded in the geophysical well logging is considered. The issue of termination of logging on a particular well is often associated with subjective expert assessments. The need for automated detection of errors and quality control of the recorded data during or immediately upon completion of studies is discussed. A brief analysis of the unreliability symptoms of record fragments is provided. An algorithm using iterative modeling techniques of incomplete data with low-dimensional manifolds for solving the problem of assessing the quality of the well logging data is proposed. Examples demonstrating the high efficiency of the iterative modeling methods for incomplete data using low-dimensional manifolds in the problem of space filling of geophysical study data are given; and the results of the numerical experiments on solving the problem of data quality control of electric logging are provided.

The need to formulate accurate requirements for the training organizations engaged in training the service personnel for passenger ropeways (PRW), and pre-certification training on the industrial safety of the ropeways is identified. “A model PRW employee” is presented. It reflects the skills and professional level of an employee, his intellectual potential capacity required under current conditions taking into account the requirements of Rostekhnadzor. The prospects for applying the distance learning methods using the information and communication technologies to significantly reduce the cost of training are identified. Thus, the training time can be distributed more reasonably; the efficiency of the expertise formation increases. The program “Inforesurs-Certification” which has a number of competitive advantages is proposed and analyzed. In particular, it can help employees of the enterprises far removed from the training center passing the pre-certification training. At this, one can work with the program at any time using any device (laptop, tablet PC, smartphone, etc.). The training material retention level increases. The opportunity of regular communication with a tutor or a supervisor (mobile telephony, emailing), and an adequate control contribute to it. This cuts the on-job training time and significantly decreases its cost.

The optimization algorithm for solving homogeneous allocation problems of the scheduling theory is described and proved. It is a modification of Romanovsky’s algorithm known in this problem domain. Romanovsky’s algorithm is a classical version of the branch-and-bound method with one-way traversing a decision tree. A systematic study of this algorithm that allows revealing reasons for its operate time increment when traversing some decision tree branches is carried out. It allows proposing modification free of the revealed shortcoming. It is called a combinatorial-modified Romanovsky's algorithm. The essence of this modification is as follows. In the process of solving the allocation problem, those rules, stages, and steps that lead to the sorting on executors the sets of tasks deliberately duplicating the previous effects are selectively skipped. The essence of the new algorithm is illustrated by an example. The statistically presented studies are resulted. They demonstrate the algorithm capabilities on the high dimensional allocation problems. (Such problems cannot be solved by the classical algorithm due to the limited timing budgets.) The results of processing these solutions have shown that the new modification does not solve the problem of NP-complete allocation tasks, but it provides a resource-time gain associated with the significant reduction in the exponential model index of the average solution time.

The mechanism of water rise in the xylem which allows the description of the water distribution in plants taking into account their anatomy, architectural form, and the influencing external factors is considered. The assumption is made that the primary mechanism for the water promotion in plants is a capillary rise. The major driving force to lift water to the top of the plant is the superficial tension in the capillary menisci. It has been established that the condition for lifting water in plants is, firstly, the presence of the water horizontal movement. Secondly, the total cross-section area of capillaries should increase from the butt-end to the top. It is shown that the plant height is determined by the number of its lateral branches, as well as the presence of cross perforated plates in the xylem vessels. The mechanism of the self-oscillating mode of the plant transpiration at small time intervals is explained.

The technique of the discrete control of a continuous object is considered by the example of a DC motor. The proposed method can simplify the procedure of selecting the desired properties of the synthesized control system, and reduce the control identification to a standard problem on the linear equation system solution with regard to the inequality constraints at each sample spacing. The desired properties of the synthesized system are specified through the reference transient. The quadratic performance criterion that characterizes the deviation of the transition process from the reference at the equally separated moments of time is applied. This approach allows a real-time control of the object with account to the restrictions of both to the controlling action, and to the phase control system coordinates. Thus, it is possible to achieve absence of overshoot and oscillability.

The effect of different methods of accounting error components of the engineering system on the treatment process to achieve the desired product quality is considered. The feasibility of the inherited and operational characteristic control based on the intelligent control systems is described. The technique of the part squareness estimate is offered. The novelty of the approach is in analyzing the effect of the combined characteristics that is more informative versus the effect estimate of each of them. An algorithm for the function calculation program of distributing the cutterpath coordinates used to evaluate entering the acceptable range is presented. An example of the probable error calculation procedure application including the effect of deviation of the tool actual trajectory from the CNC programmed one under part cutting on the multi-operation machine is provided.

The research results on determining the dependence of gas-thermal coating porosity on the laser radiation parameters are presented. At the first stage of solving the problem, on the basis of the analytical relationships, laser impact on the surface layers of the gas-thermal coating is described. Here, its discontinuity caused by the occurrence of open and closed pores is recognized. It is shown that for reducing the coating porosity under the laser impact, the coating surface temperature is to be set in the range of “fusion point-boiling point”. A temperature rise above this range caused by the radiation intensity increase leads to evaporation of surface coating layers through its complete removal in the heat effected zone. At the second stage, field research is conducted: pre-sprayed gas-thermal coatings of two types are processed by laser. The coatings based on the metallic (PN-85-U-15) and non-metallic (Al₂O₃) components are studied. The porosity modification is evaluated quantitatively using the image processing program developed in Visual Studio 2008 by pixel comparison of microstructure of the area occupied by pores and the coating material. It is established that the laser impact leads to decreasing in the average porosity of the gas-thermal coatings. Porosity of the coating based on the PN-85-U-15 alloy decreases from 17 % at the initial state to 5–8 % after the laser treatment. The corresponding figures for the ceramic coating Al₂O₃ are 24.5 % and 15–18 %.

A technique for selecting an electrode material used when applying the electrospark method onto a metal surface layer is described. The technique is based on the study of the mechanical properties of the coating by nanoindentation. The coverage microhardness distribution in depth for a number of the investigated materials is developed. As a second characteristic of the material, the plasticity index reflecting the structural state of the material is used during the indentation. Value H/E is also used to describe the capability of materials to frictional wear. A qualitative comparative characteristic — ratio H³/E² was used to assess the resistance of materials to plastic deformation. Based on the analysis of the obtained results, a reasonable choice of the electrode material which creates coatings with sufficiently high mechanical properties is made. The relevance of the study is proved by the advantages of the electrospark alloying (ESA) which is an effective method of impact on the surface layers of the various parts.

It is shown that the existing chromizing processes are characterized by a number of shortcomings. It is proposed to use the microarc thermochemical treatment technology to form a carbide coating on the material surface. Thermodynamic calculations on the reducing reactions of chromium oxide which is the diffusion source are made. It is revealed that the most probable reaction behavior is the chromium oxide reduction by methane and carbon with the formation of atomic chrome, and a consistent formation of Cr₃C₂, Cr₇C₃, and Cr₂₃C₆ carbides with an increase in temperature. The obtained results are checked through experiments. As a result of the hardening processing, a surface layer on the basis of chromium carbides with the depth of 20–25 microns is produced under which there is a carbonized area of eutectoid concentration, followed by a baseline ferrite-pearlitic structure.

The problem of elastic sliding in the ‘wheel — road surface’ contact is considered. A mathematical surface interaction model is developed. The model presented here suggests that the road surface deformation processes can be neglected. The wheel is modeled as a set of elastic rim sectors mounted on an elastic disc. The model dynamics is mainly influenced by the interaction force of the rim sectors with the wheel center, the intersectional interaction force, and the contact surface interaction force. The experimental studies using numerical simulation methods are conducted. It is discovered that there is a dependence of the stalling load value on the other wheel properties. The obtained results are of interest for solving problems on the wheel motion control to prevent the contact disruption. The used holistic approach allows identifying the emergence that influences the overall system trajectory.

The comparative analysis of the effectiveness of Goldberg and Holland’s classical models and their modifications using various options of the generational strategy is presented. The concept assuming that the number of individuals in a generation does not change is used in the classical genetic algorithms. An approach advancing the efficiency of standard Goldberg and Holland’s models through varying the number of individuals in a generation is considered. Various embodiments of the generational strategy are used to solve the homogeneous minimax scheduling problem related to the class of NP-complete problems. The computational experiment conducted for a various number of processors and works has shown that this approach can significantly improve the genetic algorithm efficiency by small changes in the standard models allowing obtain the solution that is closer to the accurate solution.

The problem of data preparation to recover the three-dimensional structure of the scene including points, segments, straight lines, etc., using video obtained from a moving camera around a static scene is considered. Based on the analysis of the existing methods, the methodology and algorithm of the data selection and preparation for recovering the three-dimensional scene structure are provided. Canny filter and Sobel operator complemented with calculating the algorithm SURF (Speeded Up Robust Feature) descriptors is taken as a basis. To filter noise from frames, wavelet filters are proposed. This allows obtaining an object contour extraction algorithm in the frame, and its comparison with the object contour in the next frame, which is the input data for the majority of algorithms of the three-dimensional scene reconstruction.

Primary channels of the energy dissipation under friction and material cutting are considered. On the basis of the known testing data, it is shown that not all the energy released in these processes is spent on the wear process with the formation of wear particles. A new approach is used to calculate friction and wear characteristics. Proposed dependences differ from the known ones in that they to the fuller extent take into account the quantity of the friction energy “responsible” for the deterioration.The known approaches to assess the energy balance under friction and cutting are analyzed. The relationship between the surface energy and absorbed energy of materials is shown through comparing energy (thermal) costs in macrovolumes and on the actual contact spots. A quantity of energy “responsible” for wear is estimated in the first approximation.

The implementation of the equipment selection process in the information network design system on the basis of fuzzy criteria is considered. The selection is made in the relational database by fuzzy SQL-queries generated in the design system program shell. The algorithm of the fuzzy SQL-queries assignment is proposed. An example of constructing a fuzzy query to select the best equipment in terms of price and quality is given. A fragment of the graphic system interface which contains an equipment selection window is presented. The described method of performing fuzzy queries is applicable to the implementation of a fuzzy search in various subject areas, it does not require any additional knowledge in fuzzy logic, and it automates the membership function formation process of the linguistic variable terms. The future activities will be linked to the expansion of the system interface capabilities on the direct designing of the fuzzy queries by a user.

The experimental research results of the mixture quality in the vibration mixer with a profile bottom depending on the process life, mixer bottom geometry, and vibration parameters (amplitude and frequency of fluctuations) are presented. The technique for continuous determining the mixture quality in time is offered for investigating the process of vibratory mixing model material at the pilot unit using the video shooting, and with the footage postprocessing. The applicability domain of the offered research method of the vibration mixing process is defined. The heterogeneity coefficient is accepted as a criterion of the mixture quality assessment. Particular attention is paid to the statistical analysis of the experimental data. The experiment results are visualized and presented in the form of the mathematical relation of the mixture heterogeneity coefficient and the process life. The theoretical solutions about the dependence of the mixture quality on the mixing time are confirmed experimentally.