Vol 22, No 5 (2020)

The article considers a systematic approach to modeling the composition and relationship of elements of the structure of the service production complex and their interaction, due to the unity of goals and functions performed by them. When solving these problems, the main problem is choosing the best solution. The article implements a method based on constructing sufficiently adequate mathematical models of real objects and their functioning processes and comparing the results of research of these models.

According to the results of the study, it was found that irradiation of the tabletted preparation of pentoxifylline leads to an increase in its antiaggregatory activity. The aim of this work is to study the effect of a pulsed magnetic field of high intensity on the antiaggregatory activity of the pure substance of petoxifylline. When exposed to a pulsed magnetic field on the pure substance of pentoxifylline (without the presence of excipients), changes in the antiaggregatory activity of the drug were not detected. Irradiation with a pulsed magnetic field was carried out on an MIU-15 setup at various magnetic field strengths with single-turn and multi-turn inductors with the number of pulses n = 1. The authors put forward a hypothesis that excipients in a tabletted medicinal product affect the change in biological activity after exposure to the drug by a pulsed magnetic field of high intensity. The study of the pure substance of pentoxifylline for antiaggregatory activity was carried out on an AT-02 platelet aggregation analyzer. Control samples of the medicinal product were not exposed to the magnetic field. It is assumed that the presence of excipients in the tablet form of pentoxifylline after exposure to a pulsed magnetic field can cause a change in the conformation of the drug molecule. In addition, a transition from one conformation to another is possible due to abrupt changes in properties, i.e. when exposed to a high-intensity magnetic field. An antiplatelet agent with excipients, being in a magnetic field, goes into a more active state, after which it retains it for some time, in which an increase in pharmacological activity is manifested.

Scientific research shows that ensuring the reliability of the product, reducing the time and cost of its production, is achieved, first, by coordinating the interests of the company›s employees in the process of organizing the production of the product; secondly, by implementing modern information systems and technologies at the stages of design and technological preparation of the enterprise›s production. The introduction of information systems and technologies in the enterprise, as well as any production process, involves the interaction of employees of the enterprise, between which there may be conflicts of interest. Accordingly, the relevance of this research is determined by the need to identify these conflicts and take measures to eliminate them.

The authors proposed methodology for creating a knowledgebase of after-sales support of aircraft. Methods for filling the knowledge base at the stage of preparation for production and pilot production of aircraft have been formed. The mechanism of interaction of after-sales service participants with the knowledge base has been presented.

The questions of negative impact of infrasound in conditions of urban territory of city district Samara are considered. Analysis of sources of infrasound radiation have been carried out. Peculiarities of the negative impact of infrasound are considered. Results of measurements of infrasound are allowing to conclude that there is exist exceeding of normative values of infrasound in a number of zones of living territory of city district Samara. It is necessary to develop and to implement the measures for reduction of negative impact of infrasound.

The control problems on a space robot during its approach to an information geostationary satellite are considered. The robot motion control system uses an electric propulsion system with 8 engines at the pulse-width modulation of their thrust values and a gyroscopic moment cluster based on 4 gyrodines with digital control. Numerical results are presented that demonstrate the effectiveness of the developed discrete guidance and control algorithms.

Methods for guidance and motion control of a space robot during a flyby of a geostationary satellite at a visual monitoring its technical state are considered. Numerical results are presented that demonstrate the effectiveness of the developed discrete guidance and control algorithms.

Oil recovery estimation is the most important tasks after calculation of oil in place and thereafter in oil development plans. There are a lot of appropriate methods for such estimation - displacement coefficient, sweep efficiency, waterflood efficiency, using final well water cut, with respect to fluid mobilities, reservoir thickness and porosity, absolute and relative permeability. Often such parameters are taken from similar nearest reservoirs due to lack of the data. Reservoir simulation is another method for oil recovery estimation although it has many shortcomings. Oil recovery estimation presented in this paper is based on widely known k-means unsupervised machine learning algorytms. Silhouette technics is used for choosing main clusters. Parameter euristics based on local Volga-Ural region data is diveded by clusters for oil recovery. Reservoir classification methodology can dramatically improve ultimate recovery estimation.

The developed methodology determines the weight characteristics of a wing of high aspect ratio using the integral criterion - the carrying load factor coefficient and numerical mathematical modeling in the fields of aerodynamics and rigid body mechanics. The paper considers the application of a multi-objective optimization method based on genetic algorithms to find the rational position of the spars in the wing when choosing its structural scheme. The calculation of the air load distribution within the framework of the proposed method is based on mathematical modeling of flows by the vortex lattice method. The ideal weight criterion is calculated based on the stress state of the wing structure obtained by the finite element method. The efficiency of the method is shown by the example of solving a demonstration problem to assess the influence of several geometric parameters of the wing on the air load distribution and its weight characteristics.

The article offers options for constructing anatomically shaped vertebra implants. We have created various constructions of human thoracic vertebrae implants. The 3D model of a vertebral implant structure consists of three elements that are mated along the surfaces passing through the vertebral foramen (vertebraeforamen). To ensure the rigidity of the implant structure in the assembled state, the interface surfaces of its elements were made as freeform surfaces. Fixation of the implant elements in the assembled state is carried out using fasteners, which are either removed or retained after patient rehabilitation. The interface surfaces of the implant elements, the place of installation of the fasteners, as well as its type are determined by medical indications: existing medical practice, the nature of the vertebral injury, the plan for the upcoming surgical intervention, etc. The assembled vertebral implant structure can have a cavity in the center of the structure or be integral. In the first case, the implant has a weight equal to the weight of the vertebra before it was injured. In the second case, the weight of the implant exceeds the weight of the vertebra before it was injured. In this case, the rigidity of the implant when the structure is compressed exceeds the rigidity of a healthy vertebra. On the surface of the 3D model of the vertebra implant, it is possible to perform microroughnesses of various structures. This circumstance makes it possible to simulate the modes and types of technological impact during the manufacture of an implant. The presence of microroughnesses on the surface of the implant contributes to its successful integration into adjacent anatomical structures, and also has antibacterial properties. The implant designs developed by us can be used to treat injuries of the human cervical, thoracic and lumbar vertebrae.