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Role of carbon matrix heteroatoms at synthesis of carbons for catalysis and energy applications

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Journal of Energy Chemistry 2013年第2期22卷 174-182页

作者： volodymyr V. Strelko Institute for Sorption and Problems of Endoecology of National Academy of Sciences of Ukraine 13 General Naumov str. Kiev 03164 Ukraine

The conceptual ideas about the positive effects of N- and O-heteroatoms on the reactivity of carbons in gasification processes, their catalytic activity in electron transfer reactions, as well as the performance of the electrode double-layer supercapacitors due to their electron-donating influence on the 7r-conjugated system of graphene layers have been developed. This influence decreases both work function and band gap of carbons, and also significantly affects their electron-donating properties. As a result of our investigations based on quantum chemical calculations of model graphene clusters with N- and O-heteroatoms in different positions, prognostic data have been obtained. These data have been confirmed by our experimental results of catalytic activity of corresponding carbons in H202 decomposition reaction, their reactivity in gasification processes, and also their performance as electrodes in supercapacitors.

关键词： N- and O-heteroatoms carbon catalysts gasification of carbons supercapacitors alkali and alkaline earth metals

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Reinforcement Learning Model for Energy System Management to Ensure Energy Efficiency and Comfort in Buildings

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Energy Engineering 2024年第12期121卷 3617-3634页

作者： Inna Bilous Dmytro Biriukov Dmytro Karpenko Tatiana Eutukhova Oleksandr Novoseltsev volodymyr Voloshchuk Department of Heat and Alternative Power Engineering National Technical University of Ukraine“KPI”Kyiv03056Ukraine Department of Structural Transformation of the Fuel and Energy Complex General Energy Institute of NAS of UkraineKyiv03150Ukraine

This article focuses on the challenges ofmodeling energy supply systems for buildings,encompassing both methods and tools for simulating thermal regimes and engineering systems within *** the comfort of living or working in buildings often necessitates increased consumption of energy and material,such as for thermal upgrades,which consequently incurs additional economic *** is crucial to acknowledge that such improvements do not always lead to a decrease in total pollutant emissions,considering emissions across all stages of production and usage of energy and materials aimed at boosting energy efficiency and comfort in *** addition,it explores the methods and mechanisms for modeling the operating modes of electric boilers used to collectively improve energy efficiency and indoor climatic *** the developed mathematical models,the study examines the dynamic states of building energy supply systems and provides recommendations for improving their *** dynamic models are executed in software environments such as MATLAB/Simscape and Python,where the component detailing schemes for various types of controllers are ***,controllers based on reinforcement learning(RL)displayed more adaptive load level *** RL-based controllers can lower instantaneous power usage by up to 35%,reduce absolute deviations from a comfortable temperature nearly by half,and cut down energy consumption by approximately 1%while maintaining *** the energy source produces a constant energy amount,the RL-based heat controllermore effectively maintains the temperature within the set range,preventing *** conclusion,the introduced energydynamic building model and its software implementation offer a versatile tool for researchers,enabling the simulation of various energy supply systems to achieve optimal energy efficiency and indoor climate control in buildings.

关键词： Building energy management building heating system dynamic modeling reinforcement learning energy efficiency comfortable temperature

Phytochemical Analysis and Antioxidant Activity of Crocus speciosus Leaves

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Phyton-International Journal of Experimental Botany 2022年第1期91卷 207-221页

作者： Olha Mykhailenko Ivan Bezruk Victoriia Volochai volodymyr Mishchenko Liudas Ivanauskas Victoriya Georgiyants Department of Pharmaceutical Chemistry National University of PharmacyKharkiv61168Ukraine Department of Pharmacognosy National University of PharmacyKharkiv61168Ukraine Department of Quality Standardisation and Certification of DrugsNational University of PharmacyKharkiv61001Ukraine Department of Analytical and Toxicological Chemistry Lithuanian University of Health SciencesKaunas44307Lithuania

The numerous studies indicate leaves of plants are a rich source of bioactive compounds that can be a valuable source of compounds used in the pharmaceutical and cosmetic *** of this study was to investigate the chemical composition and the antioxidant property of Crocus speciosus *** phytochemical screening of *** leaves revealed the presence of some following compound categories such as phenolic compounds,aminoacids,saponins,proteins,tannins,triterpenoids,glycosides,*** total flavonoids and phenolic compounds content were determined spectrophotometrically and by HPLC-DAD and *** activity was determined by ABTS radical-cation scavenging method,*** total amount of flavonoids in *** leaves was 1.07±0.02 mg RE/g(p<0.05),the total amount of phenolic compounds was 0.41±0.01 mg GAE/g(p<0.05).By HPLC-DAD-MS analysis the presence of the mangiferin,chlorogenic acid,isoorientin,kaempferol,hyperoside,and isoquercitin was established for the first time in Crocus *** antiradical activity of *** leaves extracts was 150.08±4.5μmol/g(p<0.05)and its was mainly attributed to phenolic compounds *** high amounts of flavonoids and antiradical activity in *** leaves suggests promising phytochemical and pharmacological study of this Crocus species.

关键词： Crocus speciosus flavonoids leaves antiradical activity

The use of metal hydrides in fuel cell applications

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Progress in Natural Science:Materials International 2017年第1期27卷 3-20页

作者： Mykhaylo V.Lototskyy Ivan Tolj Lydia Pickering Cordellia Sita Frano Barbir volodymyr Yartys HySA Systems Competence Centre South African Institute for Advanced Materials Chemistry (SAIAMC) University of the Western Cape University of Split Faculty of Electrical Engineering Mechanical Engineering and Naval Architecture Department of Thermodynamics and Heat Engines Institute for Energy Technology Kjeller

This paper reviews state-of-the-art developments in hydrogen energy systems which integrate fuel cells with metal hydride-based hydrogen storage. The 187 reference papers included in this review provide an overview of all major publications in the field, as well as recent work by several of the authors of the review. The review contains four parts. The first part gives an overview of the existing types of fuel cells and outlines the potential of using metal hydride stores as a source of hydrogen fuel. The second part of the review considers the suitability and optimisation of different metal hydrides based on their energy efficient thermal integration with fuel *** performances of metal hydrides are considered from the viewpoint of the reversible heat driven interaction of the metal hydrides with gaseous H;. Efficiencies of hydrogen and heat exchange in hydrogen stores to control H;charge/discharge flow rates are the focus of the third section of the review and are considered together with metal hydride – fuel cell system integration issues and the corresponding engineering solutions. Finally, the last section of the review describes specific hydrogen-fuelled systems presented in the available reference data.

关键词： Fuel cells Hydrogen storage Metal hydrides Thermal integration System development

Use of Twitter in disaster rescue: lessons learned from Hurricane Harvey

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International Journal of Digital Earth 2020年第12期13卷 1454-1466页

作者： volodymyr V.Mihunov Nina S.N.Lam Lei Zou Zheye Wang Kejin Wang Department of Environmental Sciences Louisiana State UniversityBaton RougeLAUSA Department of Geography Texas A&M UniversityCollege StationTXUSA

Despite the increasingly prominent role of social media in disaster events,studies analyzing its use in rescue operations remain *** Harvey hit Texas with unprecedented rainfall and flooding in 2017 and was marked by widespread use of social media for rescue *** conducted a survey of 195 Twitter users in Houston and surrounding communities who had requested for rescue during *** objective was to investigate our targeted group’s socioeconomic and flood exposure characteristics,report the effectiveness of Twitter,and highlight lessons learnt and suggestions made for its use in future rescue *** revealed that those requesting rescue on Twitter were better educated,employed(80%),and homeowners(81%).Majority of them were flooded(87%),but remained satisfied with current location and did not consider *** relatives and friends for rescue was most responsive and yielded higher assistance-provided rate than using *** respondents found Twitter helpful,but identified issues such as not knowing when volunteers received their requests or whether they would send *** suggested promoting Twitter accounts and hashtags that accept emergency *** study provides baseline information and actionable suggestions for first responders,community managers,and resilience practitioners to improve future rescue missions.

关键词： Twitter social media Hurricane Harvey flooding rescue online survey

Direct Derivation of the Neutrino Mass

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第2期10卷 621-646页

作者： volodymyr Krasnoholovets Department of Theoretical Physics Institute of Physics National Academy of Sciences of Ukraine Kyiv Ukraine

In this paper, the submicroscopic deterministic concept developed by the author is applied to the problem of the neutrino mass. A particle appears from space considered as a mathematical lattice of primary topological balls, and induces a deformation coat in its surrounding. The principles of the interaction of particles with space and through space between themselves are considered in detail. The approach states that real quarks possess only an integer charge (±e) and when moving they periodically change to the monopole state (⇄g) and hence, canonical particles are dynamic dyons. A neutrino emerges as a squeezed quark when it is in a monopole state, or in other words, the quark monopole state (a bubble in the tessellattice) is transferred to the appropriate lepton monopole state (a speck in the tessellattice). The self-mass (a “rest” mass) for each neutrino flavour is calculated. The calculated value of the self-mass for the electron anti-neutrino is 1.22873978 × 10-36 kg = 0.68927247 eV/c2. The concept of neutrino oscillations is revised, and another postulation is proposed, namely, that the transition from lighter to heavier flavors is due to the inelastic scattering of neutrinos on oncoming scatterers. As a result, the neutrino captures the mass defect, becomes heavier, and therefore the transitions Ve⟶Vμ and Vμ⟶Vτ occur;thus, the number of light neutrinos decreases in the neutrino flux studied.

关键词： Charge Inerton Mass Defect Monopole Neutrino Space Tessellattice

Deep Semisupervised Learning-Based Network Anomaly Detection in Heterogeneous Information Systems

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Computers, Materials & Continua 2022年第1期70卷 413-431页

作者： Nazarii Lutsiv Taras Maksymyuk Mykola Beshley Orest Lavriv volodymyr Andrushchak Anatoliy Sachenko Liberios Vokorokos Juraj Gazda Lviv Polytechnic National University Lviv79013Ukraine West Ukrainian National University Ternopil46009Ukraine Technical University of Kosice Kosice04200Slovakia

The extensive proliferation of modern information services and ubiquitous digitization of society have raised cybersecurity challenges to new *** the massive number of connected devices,opportunities for potential network attacks are nearly *** additional problem is that many low-cost devices are not equippedwith effective security protection so that they are easily hacked and applied within a network of bots(botnet)to perform distributed denial of service(DDoS)*** this paper,we propose a novel intrusion detection system(IDS)based on deep learning that aims to identify suspicious behavior in modern heterogeneous information *** proposed approach is based on a deep recurrent autoencoder that learns time series of normal network behavior and detects notable network *** additional feature of the proposed IDS is that it is trained with an optimized dataset,where the number of features is reduced by 94%without classification accuracy ***,the proposed IDS remains stable in response to slight system perturbations,which do not represent network *** proposed approach is evaluated under different simulation scenarios and provides a 99%detection accuracy over known datasets while reducing the training time by an order of magnitude.

关键词： DDoS deep semisupervised learning cybersecurity anomaly detection

Phenomena at three-phase electroslag remelting

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China Foundry 2021年第6期18卷 557-564页

作者： Zhong-li Liu Lev Medovar Ganna Stovpchenko volodymyr Petrenko Artem Sybir Yev.Volchenkov Yantai University Yantai 264005ShandongChina E.O.Paton Electric Welding Institute Kyiv 03180Ukraine National metallurgical academy of Ukraine Dnipro 49600Ukraine

The electroslag remelting(ESR)process is widely used to produce high-quality ingots and billets for high-alloyed steels and *** the single-phase and three-phase alternating current diagram with bifilar and monofilar connection are in use for heavy ingot *** numerical simulation of the three-phase bifilar circuit for the 120 t three-phase bifilar six-electrode ESR furnace at different variants of electric connection was presented and *** the bifilar diagram of power supply,the geometrical location of electrodes in a mould holds critical importance for performances:the close location of bifilar pair electrodes provides the highest heat productivity,but the equidistant location of electrodes gives a much more uniform heat *** monofilar mulit-electrode diagram of three-phase connection without phase shift shows the most uniform distribution of potential and heat generation as well as a favorable magnetic field that makes this kind the most promising for providing a high quality of heavy ingots.

关键词： electroslag remelting three-phase circuit bifilar monofilar simulation heavy ingot

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Disaster Impacts Surveillance from Social Media with Topic Modeling and Feature Extraction: Case of Hurricane Harvey

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International Journal of Disaster Risk Science 2022年第5期13卷 729-742页

作者： volodymyr V.Mihunov Navid H.Jafari Kejin Wang Nina S.N.Lam Dylan Govender Department of Environmental Sciences Louisiana State UniversityBaton RougeLA 70803USA Department of Civil and Environmental Engineering Louisiana State UniversityBaton RougeLA 70803USA Division of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA 70803USA

Twitter can supply useful information on infrastructure impacts to the emergency managers during major disasters,but it is time consuming to filter through many irrelevant *** studies have identified the types of messages that can be found on social media during disasters,but few solutions have been proposed to efficiently extract useful *** present a framework that can be applied in a timely manner to provide disaster impact information sourced from social *** framework is tested on a well-studied and data-rich case of Hurricane *** procedures consist of filtering the raw Twitter data based on keywords,location,and tweet attributes,and then applying the latent Dirichlet allocation(LDA) to separate the tweets from the disaster affected area into categories(topics) useful to emergency *** LDA revealed that out of 24 topics found in the data,nine were directly related to disaster impacts-for example,outages,closures,flooded roads,and damaged *** such as frequent hashtags,mentions,URLs,and useful images were then extracted and *** relevant tweets,along with useful images,were correlated at the county level with flood depth,distributed disaster aid(damage),and population *** correlations were found between the nine relevant topics and population density but not flood depth and damage,suggesting that more research into the suitability of social media data for disaster impacts modeling is *** results from this study provide baseline information for such efforts in the future.

关键词： Disaster impacts Hurricane Harvey Infrastructure impacts Latent Dirichlet allocation(LDA) Social media analysis Twitter data

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