Synthesis of multi-loop automatic control systems by the nonlinear programming method

The article deals with the problem of calculation of the multi-loop control systems optimal tuning parameters by numerical methods and nonlinear programming methods. For this purpose, in the paper the Optimization Toolbox of Matlab is used

Integrated project management system of scientific and technical centre in oil company "Rosneft"

Concept and structure of three level integrated project management system of in project-oriented organization have been suggested and described. Synergetic effect at such system introduction is achieved due to systemic actions in such directions as: increasing organization controllability and transparence of decision making; flow of documentation regulation; formalization and optimization of project activity; development of irredundant and consistent system of normative documents in all directions of organization activit

Дослідження впливу електростатичної обробки на експлуатаційні характеристики осьової оливи

The effect of electrostatic processing on performance characteristics of axle oil is investigated. Axle oil is used for wetting motor-axial bearings (MAB) of locomotives. There is a pressing and urgent problem of the MAB service life, which is indirectly related to the underdeveloped reserves of anti-wear properties of axle oil. To study them, it was decided to use the method of electrostatic processing, which does not require the introduction of any additives and has proven its effectiveness in the studies of other mineral oils. It is based on the ability of electric fields to destroy micellar aggregates in oil and form a solid boundary layer of molecules on friction surfaces. In the context of solving the current problem of the MAB service life, this method wasn’t considered earlier.The research was carried out by means of the «roller-pad» friction pair, which was wetted with axle oil at different load conditions and operating times. The dependences of wear of the experimental samples under different load conditions, oil operating times and degrees of electric processing are obtained.The results show that when using axle oil subjected to ESP, the wear rate of the experimental samples is reduced. Wear rate reduction depends on the oil operating time in the lubrication system. The greatest wear rate reduction of 1.92 times is noted for fresh oil. For the oil state after the locomotive run of 75 thousand km, the reduction is about 1.68 times and for the oil at the end of its service life, wear rate reduction is approximately 1.47 times.Получены результаты изменения эксплуатационных характеристик осевого масла на разных этапах наработки и при использовании метода электростатической обработки. Исследования проводились на паре трения «ролик-колодка», которая смачивалась осевым маслом на различных режимах нагрузки и степенях наработки. Получены зависимости износа экспериментальных образцов при различных режимах нагрузки, наработки масла и степени электрообработкиОтримані результати зміни експлуатаційних характеристик осьової оливи на різних етапах напрацювання та при застосуванні методу електростатичної обробки. Дослідження проводились на парі тертя «ролик-колодка», яка змочувалася осьовою оливою на різних режимах навантаження та ступенях напрацювання. Отримані залежності зносу експериментальних зразків при різних режимах навантаження, напрацювання оливи та ступеня електрообробк

Chiral photonic super-crystals based on helical van der Waals homostructures

Chirality is probably the most mysterious among all symmetry transformations. Very readily broken in biological systems, it is practically absent in naturally occurring inorganic materials and is very challenging to create artificially. Chiral optical wavefronts are often used for the identification, control and discrimination of left- and right-handed biological and other molecules. Thus, it is crucially important to create materials capable of chiral interaction with light, which would allow one to assign arbitrary chiral properties to a light field. In this paper, we utilized van der Waals technology to assemble helical homostructures with chiral properties (e. g. circular dichroism). Because of the large range of van der Waals materials available such helical homostructures can be assigned with very flexible optical properties. We demonstrate our approach by creating helical homostructures based on multilayer As$_2$S$_3$, which offers the most pronounced chiral properties even in thin structures due to its strong biaxial optically anisotropy. Our work showcases that the chirality of an electromagnetic system may emerge at an intermediate level between the molecular and the mesoscopic one due to the tailored arrangement of non-chiral layers of van der Waals crystals and without additional patterning

The Question of Construction Cluster Efficiency in Russian Regions

This article is devoted to the questions of building complex clasterization in Russian regions. The correlation analysis between the existence of the formed building cluster in each region and the volume of construction works fulfilled during the period under review is being conducted on the basis of data about the development of Russian regions generalized by Federal state statistics service. The authors examine the volumes of construction works in leading regions from the position of clusterization features, describing and analyzing key efficiency problems of construction. The authors draw a conclusion that declared cluster creation is not always based on factual building complex clusterization. As result, current situation in Russian economy seems to be problematic: regions without legally formed clusters are, in fact, more clusterized then those with announced formation

The Question of Construction Cluster Efficiency in Russian Regions

This article is devoted to the questions of building complex clasterization in Russian regions. The correlation analysis between the existence of the formed building cluster in each region and the volume of construction works fulfilled during the period under review is being conducted on the basis of data about the development of Russian regions generalized by Federal state statistics service. The authors examine the volumes of construction works in leading regions from the position of clusterization features, describing and analyzing key efficiency problems of construction. The authors draw a conclusion that declared cluster creation is not always based on factual building complex clusterization. As result, current situation in Russian economy seems to be problematic: regions without legally formed clusters are, in fact, more clusterized then those with announced formation

Analysis of electric consumption: a study in the excavation area of the modern coal mine

The growth in the power supply of coal mines over the past decades has had a significant impact on their power consumption. The use of outdated materials for assessing the coal mine energy characteristics may lead to large calculation errors. At the same time, the problem of reducing the energy intensity of coal mining does not lose its relevance. However, in order to achieve it, it is necessary to take into account the current level of development of the mechanized complex of excavation areas. The widespread introduction of SCADA systems and the development of methods for big data processing makes it possible to collect large arrays of measurements and study the power consumption of mining equipment. In this paper, on the basis of extensive arrays of electrical load measurements and technological parameters, a statistical analysis of the load of a modern Eickhoff SL 900 longwall shearer of the Kuzbass coal mine is carried out

A graph model of the topology of physical, link and network layers of an enterprise network

Many network management tasks require a network topology graph as its input. However, the lack of standard methods of network elements detection, coupled with the incompleteness and heterogeneity of the available topology data, complicate the network topology discovery process. In these conditions it is rational to separate the task of collecting data about the current topology of the network from the tasks of analyzing the collected data and building a topology graph. This approach requires a definition of the modern enterprise networks topology graphs family. Contribution of the paper is the graph model of the topology of physical, link and network layers of a modern enterprise Ethernet and IP based network. A set of theorems proved in the paper allows to infer parts of the topology graph, which are not described by data available on the network devices. Three-step process of building a topology graph using the network data and inference procedures is also proposed in the paper

Actors Interactions Research in Cloud Computing Environments Using System Dynamics Methodology

The process of cloud acton interactions has been described. This problma was considered in order to identify the key factors that affect the level of quality of services in the cloud computing environment. A model of the cloud acton interactions has been proposed using the system dynamics methodology. The model allows to identify and to research the cause-and-effect relationship between the actors interactions outlines and o1her cloud elements in terms of cloud services quality management