59 research outputs found

    Information Analysis Support for Decision-Making in Scientific and Technological Development

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    This paper presents the development of an information and analytical system to foster scientific and technological development in a given scientific field. In this work, the main software tools for implementing distributed computing, which involves a set of software components for collecting, processing, and analyzing large amounts of data, are considered. In addition, various approaches for task coordination between different sets of software are discussed and techniques for storing large amounts of data are described. The system architecture and database schema are designed and tested. Nowadays, the intellectualization of individual software agents is a key aspect of a new generation of multiagent systems. For this reason, this paper develops an approach that can organize activities of a large number of software agents to increase system intellectualization through swarm intelligence at the level of individual agents. Three remote servers were used to build and test the system deployment, comprising such components as a platform for monitoring and scheduling workflow, data storage, and a graphical user interface that enables data retrieval and interaction on the Internet

    Magnetic edge states and coherent manipulation of graphene nanoribbons

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    Graphene, a single-layer network of carbon atoms, has outstanding electrical and mechanical properties. Graphene ribbons with nanometre-scale widths (nanoribbons) should exhibit half-metallicity and quantum confinement. Magnetic edges in graphene nanoribbons have been studied extensively from a theoretical standpoint because their coherent manipulation would be a milestone for spintronic and quantum computing devices. However, experimental investigations have been hampered because nanoribbon edges cannot be produced with atomic precision and the graphene terminations that have been proposed are chemically unstable. Here we address both of these problems, by using molecular graphene nanoribbons functionalized with stable spin-bearing radical groups. We observe the predicted delocalized magnetic edge states and test theoretical models of the spin dynamics and spin–environment interactions. Comparison with a non-graphitized reference material enables us to clearly identify the characteristic behaviour of the radical-functionalized graphene nanoribbons. We quantify the parameters of spin–orbit coupling, define the interaction patterns and determine the spin decoherence channels. Even without any optimization, the spin coherence time is in the range of microseconds at room temperature, and we perform quantum inversion operations between edge and radical spins. Our approach provides a way of testing the theory of magnetism in graphene nanoribbons experimentally. The coherence times that we observe open up encouraging prospects for the use of magnetic nanoribbons in quantum spintronic devices

    Effects of Spiro-Cyclohexane Substitution of Nitroxyl Biradicals on Dynamic Nuclear Polarization

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    Spiro-substituted nitroxyl biradicals are widely used as reagents for dynamic nuclear polarization (DNP), which is especially important for biopolymer research. The main criterion for their applicability as polarizing agents is the value of the spin–spin exchange interaction parameter (J), which can vary considerably when different couplers are employed that link the radical moieties. This paper describes a study on biradicals, with a ferrocene-1,1′-diyl-substituted 1,3-diazetidine-2,4-diimine coupler, that have never been used before as DNP agents. We observed a substantial difference in the temperature dependence between Electron Paramagnetic Resonance (EPR) spectra of biradicals carrying either methyl or spirocyclohexane substituents and explain the difference using Density Functional Theory (DFT) calculation results. It was shown that the replacement of methyl groups by spirocycles near the N-O group leads to an increase in the contribution of conformers having J ≈ 0. The DNP gain observed for the biradicals with methyl substituents is three times higher than that for the spiro-substituted nitroxyl biradicals and is inversely proportional to the contribution of biradicals manifesting the negligible exchange interaction. The effects of nucleophiles and substituents in the nitroxide biradicals on the ring-opening reaction of 1,3-diazetidine and the influence of the ring opening on the exchange interaction were also investigated. It was found that in contrast to the methyl-substituted nitroxide biradical (where we observed the ring-opening reaction upon the addition of amines), the ring opening does not occur in the spiro-substituted biradical owing to a steric barrier created by the bulky cyclohexyl substituents

    Demand management by active consumers in intelligent electric power systems

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    The approaches to demand management by active consumers through forming a given schedule of power consumption in the required period of time based on the solution of the optimization problem in the form of maximizing the power of connected controlled electric receivers of various types are presented. The model of demand management by active consumers is justified, taking into account the following factors: load sensitivity for connecting a transformer substation to a change in consumer load; load priority; consistent load reduction levels with flexible performance and power control; permissible set of electric receivers in accordance with the technological process, network schedule, other logical conditions corresponding to adjacency lists. An algorithm has been developed for limiting power on the part of active consumers based on the widespread use of digital data processing technologies, modern technical means of measurement, control and switching of end consumers in real time. The presented research results indicate the validity of the demand management method by active consumers in the normal mode of intelligent electric power systems and the possibility of its practical implementation in an industrial enterprise with reference to the technological process

    Advanced methods of transportation and distribution of electrical power in smart power grids of railways

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    The relevance of the work is determined by the need to improve the electrical distribution grids of railways on the basis of digital technologies. The article presents advanced methods of transportation and distribution of electric power in smart power grids of railways based on multi-agent control. The analysis of the power supply system for stationary railroad consumers was performed and advanced ways of their development were defined. These methods should provide increased speed, adaptive determination of restrictions on using electric power equipment, management of mode parameters, sectioning and power flow modes in electrical distribution grids, restoration of power supply after emergency events. The method of adaptive control of transportation and distribution of electric energy in the power supply system of stationary railway consumers is developed based on the hierarchical structure of IEC 61850. This method takes into account the coordination of managing and local controllers in the data exchange environment, the control results and the variable area of responsibility of controllers and their division according to their functional purpose based on the multi-agent approach. The method of power flow control was developed to reduce power losses, increase the capacity of transport channels and ensure the restoration of the normal mode of the electric network by reconfiguring it and controlling active elements based on graph theory. The method takes into account the expected daily load curve, limits on the demand for capacity by active consumers and the possibility of a closed mode of electrical network operation through controlled cross-sections. The simulation results presented on the test circuit have showed the feasibility and efficiency of the proposed approaches

    Demand management by active consumers in intelligent electric power systems

    No full text
    The approaches to demand management by active consumers through forming a given schedule of power consumption in the required period of time based on the solution of the optimization problem in the form of maximizing the power of connected controlled electric receivers of various types are presented. The model of demand management by active consumers is justified, taking into account the following factors: load sensitivity for connecting a transformer substation to a change in consumer load; load priority; consistent load reduction levels with flexible performance and power control; permissible set of electric receivers in accordance with the technological process, network schedule, other logical conditions corresponding to adjacency lists. An algorithm has been developed for limiting power on the part of active consumers based on the widespread use of digital data processing technologies, modern technical means of measurement, control and switching of end consumers in real time. The presented research results indicate the validity of the demand management method by active consumers in the normal mode of intelligent electric power systems and the possibility of its practical implementation in an industrial enterprise with reference to the technological process

    Implementation of the method of adaptive management of electric power transmission in distribution electric networks of railways

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    The separation of the electric grid cluster rendering services related to transmission of electric power through electric grids from the railways electric power supply system within the Russian Railways holding will make it possible to proceed with to the modernization of the distribution electric networks of the railways at the expense of the investment component of the tariff. The innovative development of the grid company of the Russian Railways holding company is to be synchronized with its technological indicators with PJSC FGC UES and PJSC Rosseti and is aimed at creating a stable, efficient, flexible and intelligent electric power infrastructure. The aim of the present research is to increase the efficiency of electric power transmission in the distribution electric networks of railways due to the adaptive control of the regulators of the operation mode parameters. The implementation of the method of adaptive control of electric power transmission in distribution electric networks of railways based on the agent approach is presented

    Implementation of the method of adaptive management of electric power transmission in distribution electric networks of railways

    No full text
    The separation of the electric grid cluster rendering services related to transmission of electric power through electric grids from the railways electric power supply system within the Russian Railways holding will make it possible to proceed with to the modernization of the distribution electric networks of the railways at the expense of the investment component of the tariff. The innovative development of the grid company of the Russian Railways holding company is to be synchronized with its technological indicators with PJSC FGC UES and PJSC Rosseti and is aimed at creating a stable, efficient, flexible and intelligent electric power infrastructure. The aim of the present research is to increase the efficiency of electric power transmission in the distribution electric networks of railways due to the adaptive control of the regulators of the operation mode parameters. The implementation of the method of adaptive control of electric power transmission in distribution electric networks of railways based on the agent approach is presented

    Estimation of Absolute Spin Counts in Nitronyl Nitroxide-Bearing Graphene Nanoribbons

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    The degrees of spin labeling of a polyphenylene-based polymer and its graphitized derivative with a stable nitronyl nitroxide were evaluated by estimating the absolute numbers of spins in a set of samples using continuous wave (CW) electron spin resonance (ESR). For these particular systems, the degrees of spin labeling were found to be approximately 0.8% and 1.3%, respectively. The developed procedure complements the more advanced time-resolved/cryogenic ESR studies on these systems by focusing on the stable spin labels introduced in these magnetically intricate materials and providing an estimate of their absolute amount, which is indispensable in the development of synthetic approaches to prepare modified graphene systems and for evaluating the success of these systems
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