127 research outputs found
The economic part of the design of the electrical part of IES and therelay protection of the turbogenerator
Evaluation of the economic value of the project is an important condition for searching financial sources for carryingout scientific research. This evaluation is an important factor for developers who must rely on existing perspectives ofongoing research. Thanks to this assessment, the engineer can find a partner for a qualitative and rapid scientificresearch, as well as the approval and commercialization of the results in this paper a comparative evaluation of therelay protection characteristics of different firms (EKRA, ABB, GE) was carried out. The main criteria for evaluatingrelay protection in the global market are identified: noise immunity, reliability, functional capacity, the quality of theintelligent interface, etc. The relationship of all identified criteria is established. As a result, the most favorable versionof the relay protection of the turbogenerator was obtained. The obtained criteria can be used to evaluate the relayprotection of other power plants (transformers, autotransformers, powerful turbo-generators)
Temperature and Concentration Traces of Spray Flows During Motion in a Flame
Heat and mass transfer models are developed on the base of experimental data and using Ansys Fluent software. These models allow prediction of the temperature and concentration traces of droplets. Transfer mechanisms of water droplets from different flames of flammable liquid (ethanol, kerosene Π benzine) with temperature gases 450-850 Π are analyzed. The paper considers aerosol flows with droplets sizes of 0.04-0.4 mm and concentration of 3.8Β·10{-5}-10.3Β·10{-5} m{3} of droplets/m{3} of gas. The maximum gas temperature reduction in the trace of a moving liquid is ranged from 850 K to 600 K. The times of keeping the low temperature of the gas-vapor mixture in the droplets trace are from 13 s to 25 s relative to the initial gas temperature
THE METHOD OF AUTOMATED BUILDING OF DOMAIN ONTOLOGY
This article is devoted to the tasks of automating the construction of domain ontologies. In the beginning, the limitations and problems of constructing the ontology of the domain using the well-known methods are discussed. Next, a model of the domain ontology is proposed, which provides the ability to automatically build the ontological hierarchy, including the automatic synthesis of generalized concepts. Then, the article discusses the method of building an ontology based on the proposed model using machine learning, and discusses its capabilities and limitations
RESEARCH OF APPROACHES TO THE RECOGNITION OF SEMANTIC IMAGES OF SCIENTIFIC PUBLICATIONS BASED ON NEURAL NETWORKS
The paper is devoted to the problems of orientation and navigation in the world of verbal presentation of scientific knowledge. The solution of these problems is currently hampered by the lack of intelligent information retrieval systems that allow comparing descriptions of various scientific works at the level of coincidence of semantic situations, rather than keywords. The article discusses methods for the formation and recognition of semantic images of scientific publications belonging to specific subject areas. The method for constructing a semantic image of a scientific text developed by Iuliia Bruttan allows to form an image of the text of a scientific publication, which can be used as input data for a neural network. Training of this neural network will automate the processes of pattern recognition and classification of scientific publications according to specified criteria. The approaches to the recognition of semantic images of scientific publications based on neural networks considered in the paper can be used to organize the semantic search for scientific publications, as well as in the design of intelligent information retrieval systems
COMPARISON OF OBJECT-ORIENTED PROGRAMMING AND DATA-ORIENTED DESIGN FOR IMPLEMENTING TRADING STRATEGIES BACKTESTER
This research proposes a way to accelerate backtesting of trading strategies using data-oriented design (DOD). The research discusses the differences between DOD and object-oriented approach (OOP), which is the most popular at the current moment. Then, the paper proposes efficient way to parallelize a backtesting using DOD. Finally, this research provides a performance comparison between DOD and OOP backtester implementations on the example of typical technical indicators. The comparison shows that use of DOD can speed up the process of quantitative features calculation up to 33% and allows for parallelization scheme that better utilizes resources in multiprocessor systems
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